1 /* Fold a constant sub-tree into a single node for C-compiler
2 Copyright (C) 1987, 1988, 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999,
3 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007
4 Free Software Foundation, Inc.
6 This file is part of GCC.
8 GCC is free software; you can redistribute it and/or modify it under
9 the terms of the GNU General Public License as published by the Free
10 Software Foundation; either version 3, or (at your option) any later
13 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
14 WARRANTY; without even the implied warranty of MERCHANTABILITY or
15 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
18 You should have received a copy of the GNU General Public License
19 along with GCC; see the file COPYING3. If not see
20 <http://www.gnu.org/licenses/>. */
22 /*@@ This file should be rewritten to use an arbitrary precision
23 @@ representation for "struct tree_int_cst" and "struct tree_real_cst".
24 @@ Perhaps the routines could also be used for bc/dc, and made a lib.
25 @@ The routines that translate from the ap rep should
26 @@ warn if precision et. al. is lost.
27 @@ This would also make life easier when this technology is used
28 @@ for cross-compilers. */
30 /* The entry points in this file are fold, size_int_wide, size_binop
31 and force_fit_type_double.
33 fold takes a tree as argument and returns a simplified tree.
35 size_binop takes a tree code for an arithmetic operation
36 and two operands that are trees, and produces a tree for the
37 result, assuming the type comes from `sizetype'.
39 size_int takes an integer value, and creates a tree constant
40 with type from `sizetype'.
42 force_fit_type_double takes a constant, an overflowable flag and a
43 prior overflow indicator. It forces the value to fit the type and
46 Note: Since the folders get called on non-gimple code as well as
47 gimple code, we need to handle GIMPLE tuples as well as their
48 corresponding tree equivalents. */
52 #include "coretypes.h"
57 #include "fixed-value.h"
65 #include "langhooks.h"
68 /* Nonzero if we are folding constants inside an initializer; zero
70 int folding_initializer
= 0;
72 /* The following constants represent a bit based encoding of GCC's
73 comparison operators. This encoding simplifies transformations
74 on relational comparison operators, such as AND and OR. */
75 enum comparison_code
{
94 static void encode (HOST_WIDE_INT
*, unsigned HOST_WIDE_INT
, HOST_WIDE_INT
);
95 static void decode (HOST_WIDE_INT
*, unsigned HOST_WIDE_INT
*, HOST_WIDE_INT
*);
96 static bool negate_mathfn_p (enum built_in_function
);
97 static bool negate_expr_p (tree
);
98 static tree
negate_expr (tree
);
99 static tree
split_tree (tree
, enum tree_code
, tree
*, tree
*, tree
*, int);
100 static tree
associate_trees (tree
, tree
, enum tree_code
, tree
);
101 static tree
const_binop (enum tree_code
, tree
, tree
, int);
102 static enum comparison_code
comparison_to_compcode (enum tree_code
);
103 static enum tree_code
compcode_to_comparison (enum comparison_code
);
104 static tree
combine_comparisons (enum tree_code
, enum tree_code
,
105 enum tree_code
, tree
, tree
, tree
);
106 static int truth_value_p (enum tree_code
);
107 static int operand_equal_for_comparison_p (tree
, tree
, tree
);
108 static int twoval_comparison_p (tree
, tree
*, tree
*, int *);
109 static tree
eval_subst (tree
, tree
, tree
, tree
, tree
);
110 static tree
pedantic_omit_one_operand (tree
, tree
, tree
);
111 static tree
distribute_bit_expr (enum tree_code
, tree
, tree
, tree
);
112 static tree
make_bit_field_ref (tree
, tree
, int, int, int);
113 static tree
optimize_bit_field_compare (enum tree_code
, tree
, tree
, tree
);
114 static tree
decode_field_reference (tree
, HOST_WIDE_INT
*, HOST_WIDE_INT
*,
115 enum machine_mode
*, int *, int *,
117 static int all_ones_mask_p (const_tree
, int);
118 static tree
sign_bit_p (tree
, const_tree
);
119 static int simple_operand_p (const_tree
);
120 static tree
range_binop (enum tree_code
, tree
, tree
, int, tree
, int);
121 static tree
range_predecessor (tree
);
122 static tree
range_successor (tree
);
123 static tree
make_range (tree
, int *, tree
*, tree
*, bool *);
124 static tree
build_range_check (tree
, tree
, int, tree
, tree
);
125 static int merge_ranges (int *, tree
*, tree
*, int, tree
, tree
, int, tree
,
127 static tree
fold_range_test (enum tree_code
, tree
, tree
, tree
);
128 static tree
fold_cond_expr_with_comparison (tree
, tree
, tree
, tree
);
129 static tree
unextend (tree
, int, int, tree
);
130 static tree
fold_truthop (enum tree_code
, tree
, tree
, tree
);
131 static tree
optimize_minmax_comparison (enum tree_code
, tree
, tree
, tree
);
132 static tree
extract_muldiv (tree
, tree
, enum tree_code
, tree
, bool *);
133 static tree
extract_muldiv_1 (tree
, tree
, enum tree_code
, tree
, bool *);
134 static tree
fold_binary_op_with_conditional_arg (enum tree_code
, tree
,
137 static bool fold_real_zero_addition_p (const_tree
, const_tree
, int);
138 static tree
fold_mathfn_compare (enum built_in_function
, enum tree_code
,
140 static tree
fold_inf_compare (enum tree_code
, tree
, tree
, tree
);
141 static tree
fold_div_compare (enum tree_code
, tree
, tree
, tree
);
142 static bool reorder_operands_p (const_tree
, const_tree
);
143 static tree
fold_negate_const (tree
, tree
);
144 static tree
fold_not_const (tree
, tree
);
145 static tree
fold_relational_const (enum tree_code
, tree
, tree
, tree
);
148 /* We know that A1 + B1 = SUM1, using 2's complement arithmetic and ignoring
149 overflow. Suppose A, B and SUM have the same respective signs as A1, B1,
150 and SUM1. Then this yields nonzero if overflow occurred during the
153 Overflow occurs if A and B have the same sign, but A and SUM differ in
154 sign. Use `^' to test whether signs differ, and `< 0' to isolate the
156 #define OVERFLOW_SUM_SIGN(a, b, sum) ((~((a) ^ (b)) & ((a) ^ (sum))) < 0)
158 /* To do constant folding on INTEGER_CST nodes requires two-word arithmetic.
159 We do that by representing the two-word integer in 4 words, with only
160 HOST_BITS_PER_WIDE_INT / 2 bits stored in each word, as a positive
161 number. The value of the word is LOWPART + HIGHPART * BASE. */
164 ((x) & (((unsigned HOST_WIDE_INT) 1 << (HOST_BITS_PER_WIDE_INT / 2)) - 1))
165 #define HIGHPART(x) \
166 ((unsigned HOST_WIDE_INT) (x) >> HOST_BITS_PER_WIDE_INT / 2)
167 #define BASE ((unsigned HOST_WIDE_INT) 1 << HOST_BITS_PER_WIDE_INT / 2)
169 /* Unpack a two-word integer into 4 words.
170 LOW and HI are the integer, as two `HOST_WIDE_INT' pieces.
171 WORDS points to the array of HOST_WIDE_INTs. */
174 encode (HOST_WIDE_INT
*words
, unsigned HOST_WIDE_INT low
, HOST_WIDE_INT hi
)
176 words
[0] = LOWPART (low
);
177 words
[1] = HIGHPART (low
);
178 words
[2] = LOWPART (hi
);
179 words
[3] = HIGHPART (hi
);
182 /* Pack an array of 4 words into a two-word integer.
183 WORDS points to the array of words.
184 The integer is stored into *LOW and *HI as two `HOST_WIDE_INT' pieces. */
187 decode (HOST_WIDE_INT
*words
, unsigned HOST_WIDE_INT
*low
,
190 *low
= words
[0] + words
[1] * BASE
;
191 *hi
= words
[2] + words
[3] * BASE
;
194 /* Force the double-word integer L1, H1 to be within the range of the
195 integer type TYPE. Stores the properly truncated and sign-extended
196 double-word integer in *LV, *HV. Returns true if the operation
197 overflows, that is, argument and result are different. */
200 fit_double_type (unsigned HOST_WIDE_INT l1
, HOST_WIDE_INT h1
,
201 unsigned HOST_WIDE_INT
*lv
, HOST_WIDE_INT
*hv
, const_tree type
)
203 unsigned HOST_WIDE_INT low0
= l1
;
204 HOST_WIDE_INT high0
= h1
;
206 int sign_extended_type
;
208 if (POINTER_TYPE_P (type
)
209 || TREE_CODE (type
) == OFFSET_TYPE
)
212 prec
= TYPE_PRECISION (type
);
214 /* Size types *are* sign extended. */
215 sign_extended_type
= (!TYPE_UNSIGNED (type
)
216 || (TREE_CODE (type
) == INTEGER_TYPE
217 && TYPE_IS_SIZETYPE (type
)));
219 /* First clear all bits that are beyond the type's precision. */
220 if (prec
>= 2 * HOST_BITS_PER_WIDE_INT
)
222 else if (prec
> HOST_BITS_PER_WIDE_INT
)
223 h1
&= ~((HOST_WIDE_INT
) (-1) << (prec
- HOST_BITS_PER_WIDE_INT
));
227 if (prec
< HOST_BITS_PER_WIDE_INT
)
228 l1
&= ~((HOST_WIDE_INT
) (-1) << prec
);
231 /* Then do sign extension if necessary. */
232 if (!sign_extended_type
)
233 /* No sign extension */;
234 else if (prec
>= 2 * HOST_BITS_PER_WIDE_INT
)
235 /* Correct width already. */;
236 else if (prec
> HOST_BITS_PER_WIDE_INT
)
238 /* Sign extend top half? */
239 if (h1
& ((unsigned HOST_WIDE_INT
)1
240 << (prec
- HOST_BITS_PER_WIDE_INT
- 1)))
241 h1
|= (HOST_WIDE_INT
) (-1) << (prec
- HOST_BITS_PER_WIDE_INT
);
243 else if (prec
== HOST_BITS_PER_WIDE_INT
)
245 if ((HOST_WIDE_INT
)l1
< 0)
250 /* Sign extend bottom half? */
251 if (l1
& ((unsigned HOST_WIDE_INT
)1 << (prec
- 1)))
254 l1
|= (HOST_WIDE_INT
)(-1) << prec
;
261 /* If the value didn't fit, signal overflow. */
262 return l1
!= low0
|| h1
!= high0
;
265 /* We force the double-int HIGH:LOW to the range of the type TYPE by
266 sign or zero extending it.
267 OVERFLOWABLE indicates if we are interested
268 in overflow of the value, when >0 we are only interested in signed
269 overflow, for <0 we are interested in any overflow. OVERFLOWED
270 indicates whether overflow has already occurred. CONST_OVERFLOWED
271 indicates whether constant overflow has already occurred. We force
272 T's value to be within range of T's type (by setting to 0 or 1 all
273 the bits outside the type's range). We set TREE_OVERFLOWED if,
274 OVERFLOWED is nonzero,
275 or OVERFLOWABLE is >0 and signed overflow occurs
276 or OVERFLOWABLE is <0 and any overflow occurs
277 We return a new tree node for the extended double-int. The node
278 is shared if no overflow flags are set. */
281 force_fit_type_double (tree type
, unsigned HOST_WIDE_INT low
,
282 HOST_WIDE_INT high
, int overflowable
,
285 int sign_extended_type
;
288 /* Size types *are* sign extended. */
289 sign_extended_type
= (!TYPE_UNSIGNED (type
)
290 || (TREE_CODE (type
) == INTEGER_TYPE
291 && TYPE_IS_SIZETYPE (type
)));
293 overflow
= fit_double_type (low
, high
, &low
, &high
, type
);
295 /* If we need to set overflow flags, return a new unshared node. */
296 if (overflowed
|| overflow
)
300 || (overflowable
> 0 && sign_extended_type
))
302 tree t
= make_node (INTEGER_CST
);
303 TREE_INT_CST_LOW (t
) = low
;
304 TREE_INT_CST_HIGH (t
) = high
;
305 TREE_TYPE (t
) = type
;
306 TREE_OVERFLOW (t
) = 1;
311 /* Else build a shared node. */
312 return build_int_cst_wide (type
, low
, high
);
315 /* Add two doubleword integers with doubleword result.
316 Return nonzero if the operation overflows according to UNSIGNED_P.
317 Each argument is given as two `HOST_WIDE_INT' pieces.
318 One argument is L1 and H1; the other, L2 and H2.
319 The value is stored as two `HOST_WIDE_INT' pieces in *LV and *HV. */
322 add_double_with_sign (unsigned HOST_WIDE_INT l1
, HOST_WIDE_INT h1
,
323 unsigned HOST_WIDE_INT l2
, HOST_WIDE_INT h2
,
324 unsigned HOST_WIDE_INT
*lv
, HOST_WIDE_INT
*hv
,
327 unsigned HOST_WIDE_INT l
;
331 h
= h1
+ h2
+ (l
< l1
);
337 return (unsigned HOST_WIDE_INT
) h
< (unsigned HOST_WIDE_INT
) h1
;
339 return OVERFLOW_SUM_SIGN (h1
, h2
, h
);
342 /* Negate a doubleword integer with doubleword result.
343 Return nonzero if the operation overflows, assuming it's signed.
344 The argument is given as two `HOST_WIDE_INT' pieces in L1 and H1.
345 The value is stored as two `HOST_WIDE_INT' pieces in *LV and *HV. */
348 neg_double (unsigned HOST_WIDE_INT l1
, HOST_WIDE_INT h1
,
349 unsigned HOST_WIDE_INT
*lv
, HOST_WIDE_INT
*hv
)
355 return (*hv
& h1
) < 0;
365 /* Multiply two doubleword integers with doubleword result.
366 Return nonzero if the operation overflows according to UNSIGNED_P.
367 Each argument is given as two `HOST_WIDE_INT' pieces.
368 One argument is L1 and H1; the other, L2 and H2.
369 The value is stored as two `HOST_WIDE_INT' pieces in *LV and *HV. */
372 mul_double_with_sign (unsigned HOST_WIDE_INT l1
, HOST_WIDE_INT h1
,
373 unsigned HOST_WIDE_INT l2
, HOST_WIDE_INT h2
,
374 unsigned HOST_WIDE_INT
*lv
, HOST_WIDE_INT
*hv
,
377 HOST_WIDE_INT arg1
[4];
378 HOST_WIDE_INT arg2
[4];
379 HOST_WIDE_INT prod
[4 * 2];
380 unsigned HOST_WIDE_INT carry
;
382 unsigned HOST_WIDE_INT toplow
, neglow
;
383 HOST_WIDE_INT tophigh
, neghigh
;
385 encode (arg1
, l1
, h1
);
386 encode (arg2
, l2
, h2
);
388 memset (prod
, 0, sizeof prod
);
390 for (i
= 0; i
< 4; i
++)
393 for (j
= 0; j
< 4; j
++)
396 /* This product is <= 0xFFFE0001, the sum <= 0xFFFF0000. */
397 carry
+= arg1
[i
] * arg2
[j
];
398 /* Since prod[p] < 0xFFFF, this sum <= 0xFFFFFFFF. */
400 prod
[k
] = LOWPART (carry
);
401 carry
= HIGHPART (carry
);
406 decode (prod
, lv
, hv
);
407 decode (prod
+ 4, &toplow
, &tophigh
);
409 /* Unsigned overflow is immediate. */
411 return (toplow
| tophigh
) != 0;
413 /* Check for signed overflow by calculating the signed representation of the
414 top half of the result; it should agree with the low half's sign bit. */
417 neg_double (l2
, h2
, &neglow
, &neghigh
);
418 add_double (neglow
, neghigh
, toplow
, tophigh
, &toplow
, &tophigh
);
422 neg_double (l1
, h1
, &neglow
, &neghigh
);
423 add_double (neglow
, neghigh
, toplow
, tophigh
, &toplow
, &tophigh
);
425 return (*hv
< 0 ? ~(toplow
& tophigh
) : toplow
| tophigh
) != 0;
428 /* Shift the doubleword integer in L1, H1 left by COUNT places
429 keeping only PREC bits of result.
430 Shift right if COUNT is negative.
431 ARITH nonzero specifies arithmetic shifting; otherwise use logical shift.
432 Store the value as two `HOST_WIDE_INT' pieces in *LV and *HV. */
435 lshift_double (unsigned HOST_WIDE_INT l1
, HOST_WIDE_INT h1
,
436 HOST_WIDE_INT count
, unsigned int prec
,
437 unsigned HOST_WIDE_INT
*lv
, HOST_WIDE_INT
*hv
, int arith
)
439 unsigned HOST_WIDE_INT signmask
;
443 rshift_double (l1
, h1
, -count
, prec
, lv
, hv
, arith
);
447 if (SHIFT_COUNT_TRUNCATED
)
450 if (count
>= 2 * HOST_BITS_PER_WIDE_INT
)
452 /* Shifting by the host word size is undefined according to the
453 ANSI standard, so we must handle this as a special case. */
457 else if (count
>= HOST_BITS_PER_WIDE_INT
)
459 *hv
= l1
<< (count
- HOST_BITS_PER_WIDE_INT
);
464 *hv
= (((unsigned HOST_WIDE_INT
) h1
<< count
)
465 | (l1
>> (HOST_BITS_PER_WIDE_INT
- count
- 1) >> 1));
469 /* Sign extend all bits that are beyond the precision. */
471 signmask
= -((prec
> HOST_BITS_PER_WIDE_INT
472 ? ((unsigned HOST_WIDE_INT
) *hv
473 >> (prec
- HOST_BITS_PER_WIDE_INT
- 1))
474 : (*lv
>> (prec
- 1))) & 1);
476 if (prec
>= 2 * HOST_BITS_PER_WIDE_INT
)
478 else if (prec
>= HOST_BITS_PER_WIDE_INT
)
480 *hv
&= ~((HOST_WIDE_INT
) (-1) << (prec
- HOST_BITS_PER_WIDE_INT
));
481 *hv
|= signmask
<< (prec
- HOST_BITS_PER_WIDE_INT
);
486 *lv
&= ~((unsigned HOST_WIDE_INT
) (-1) << prec
);
487 *lv
|= signmask
<< prec
;
491 /* Shift the doubleword integer in L1, H1 right by COUNT places
492 keeping only PREC bits of result. COUNT must be positive.
493 ARITH nonzero specifies arithmetic shifting; otherwise use logical shift.
494 Store the value as two `HOST_WIDE_INT' pieces in *LV and *HV. */
497 rshift_double (unsigned HOST_WIDE_INT l1
, HOST_WIDE_INT h1
,
498 HOST_WIDE_INT count
, unsigned int prec
,
499 unsigned HOST_WIDE_INT
*lv
, HOST_WIDE_INT
*hv
,
502 unsigned HOST_WIDE_INT signmask
;
505 ? -((unsigned HOST_WIDE_INT
) h1
>> (HOST_BITS_PER_WIDE_INT
- 1))
508 if (SHIFT_COUNT_TRUNCATED
)
511 if (count
>= 2 * HOST_BITS_PER_WIDE_INT
)
513 /* Shifting by the host word size is undefined according to the
514 ANSI standard, so we must handle this as a special case. */
518 else if (count
>= HOST_BITS_PER_WIDE_INT
)
521 *lv
= (unsigned HOST_WIDE_INT
) h1
>> (count
- HOST_BITS_PER_WIDE_INT
);
525 *hv
= (unsigned HOST_WIDE_INT
) h1
>> count
;
527 | ((unsigned HOST_WIDE_INT
) h1
<< (HOST_BITS_PER_WIDE_INT
- count
- 1) << 1));
530 /* Zero / sign extend all bits that are beyond the precision. */
532 if (count
>= (HOST_WIDE_INT
)prec
)
537 else if ((prec
- count
) >= 2 * HOST_BITS_PER_WIDE_INT
)
539 else if ((prec
- count
) >= HOST_BITS_PER_WIDE_INT
)
541 *hv
&= ~((HOST_WIDE_INT
) (-1) << (prec
- count
- HOST_BITS_PER_WIDE_INT
));
542 *hv
|= signmask
<< (prec
- count
- HOST_BITS_PER_WIDE_INT
);
547 *lv
&= ~((unsigned HOST_WIDE_INT
) (-1) << (prec
- count
));
548 *lv
|= signmask
<< (prec
- count
);
552 /* Rotate the doubleword integer in L1, H1 left by COUNT places
553 keeping only PREC bits of result.
554 Rotate right if COUNT is negative.
555 Store the value as two `HOST_WIDE_INT' pieces in *LV and *HV. */
558 lrotate_double (unsigned HOST_WIDE_INT l1
, HOST_WIDE_INT h1
,
559 HOST_WIDE_INT count
, unsigned int prec
,
560 unsigned HOST_WIDE_INT
*lv
, HOST_WIDE_INT
*hv
)
562 unsigned HOST_WIDE_INT s1l
, s2l
;
563 HOST_WIDE_INT s1h
, s2h
;
569 lshift_double (l1
, h1
, count
, prec
, &s1l
, &s1h
, 0);
570 rshift_double (l1
, h1
, prec
- count
, prec
, &s2l
, &s2h
, 0);
575 /* Rotate the doubleword integer in L1, H1 left by COUNT places
576 keeping only PREC bits of result. COUNT must be positive.
577 Store the value as two `HOST_WIDE_INT' pieces in *LV and *HV. */
580 rrotate_double (unsigned HOST_WIDE_INT l1
, HOST_WIDE_INT h1
,
581 HOST_WIDE_INT count
, unsigned int prec
,
582 unsigned HOST_WIDE_INT
*lv
, HOST_WIDE_INT
*hv
)
584 unsigned HOST_WIDE_INT s1l
, s2l
;
585 HOST_WIDE_INT s1h
, s2h
;
591 rshift_double (l1
, h1
, count
, prec
, &s1l
, &s1h
, 0);
592 lshift_double (l1
, h1
, prec
- count
, prec
, &s2l
, &s2h
, 0);
597 /* Divide doubleword integer LNUM, HNUM by doubleword integer LDEN, HDEN
598 for a quotient (stored in *LQUO, *HQUO) and remainder (in *LREM, *HREM).
599 CODE is a tree code for a kind of division, one of
600 TRUNC_DIV_EXPR, FLOOR_DIV_EXPR, CEIL_DIV_EXPR, ROUND_DIV_EXPR
602 It controls how the quotient is rounded to an integer.
603 Return nonzero if the operation overflows.
604 UNS nonzero says do unsigned division. */
607 div_and_round_double (enum tree_code code
, int uns
,
608 unsigned HOST_WIDE_INT lnum_orig
, /* num == numerator == dividend */
609 HOST_WIDE_INT hnum_orig
,
610 unsigned HOST_WIDE_INT lden_orig
, /* den == denominator == divisor */
611 HOST_WIDE_INT hden_orig
,
612 unsigned HOST_WIDE_INT
*lquo
,
613 HOST_WIDE_INT
*hquo
, unsigned HOST_WIDE_INT
*lrem
,
617 HOST_WIDE_INT num
[4 + 1]; /* extra element for scaling. */
618 HOST_WIDE_INT den
[4], quo
[4];
620 unsigned HOST_WIDE_INT work
;
621 unsigned HOST_WIDE_INT carry
= 0;
622 unsigned HOST_WIDE_INT lnum
= lnum_orig
;
623 HOST_WIDE_INT hnum
= hnum_orig
;
624 unsigned HOST_WIDE_INT lden
= lden_orig
;
625 HOST_WIDE_INT hden
= hden_orig
;
628 if (hden
== 0 && lden
== 0)
629 overflow
= 1, lden
= 1;
631 /* Calculate quotient sign and convert operands to unsigned. */
637 /* (minimum integer) / (-1) is the only overflow case. */
638 if (neg_double (lnum
, hnum
, &lnum
, &hnum
)
639 && ((HOST_WIDE_INT
) lden
& hden
) == -1)
645 neg_double (lden
, hden
, &lden
, &hden
);
649 if (hnum
== 0 && hden
== 0)
650 { /* single precision */
652 /* This unsigned division rounds toward zero. */
658 { /* trivial case: dividend < divisor */
659 /* hden != 0 already checked. */
666 memset (quo
, 0, sizeof quo
);
668 memset (num
, 0, sizeof num
); /* to zero 9th element */
669 memset (den
, 0, sizeof den
);
671 encode (num
, lnum
, hnum
);
672 encode (den
, lden
, hden
);
674 /* Special code for when the divisor < BASE. */
675 if (hden
== 0 && lden
< (unsigned HOST_WIDE_INT
) BASE
)
677 /* hnum != 0 already checked. */
678 for (i
= 4 - 1; i
>= 0; i
--)
680 work
= num
[i
] + carry
* BASE
;
681 quo
[i
] = work
/ lden
;
687 /* Full double precision division,
688 with thanks to Don Knuth's "Seminumerical Algorithms". */
689 int num_hi_sig
, den_hi_sig
;
690 unsigned HOST_WIDE_INT quo_est
, scale
;
692 /* Find the highest nonzero divisor digit. */
693 for (i
= 4 - 1;; i
--)
700 /* Insure that the first digit of the divisor is at least BASE/2.
701 This is required by the quotient digit estimation algorithm. */
703 scale
= BASE
/ (den
[den_hi_sig
] + 1);
705 { /* scale divisor and dividend */
707 for (i
= 0; i
<= 4 - 1; i
++)
709 work
= (num
[i
] * scale
) + carry
;
710 num
[i
] = LOWPART (work
);
711 carry
= HIGHPART (work
);
716 for (i
= 0; i
<= 4 - 1; i
++)
718 work
= (den
[i
] * scale
) + carry
;
719 den
[i
] = LOWPART (work
);
720 carry
= HIGHPART (work
);
721 if (den
[i
] != 0) den_hi_sig
= i
;
728 for (i
= num_hi_sig
- den_hi_sig
- 1; i
>= 0; i
--)
730 /* Guess the next quotient digit, quo_est, by dividing the first
731 two remaining dividend digits by the high order quotient digit.
732 quo_est is never low and is at most 2 high. */
733 unsigned HOST_WIDE_INT tmp
;
735 num_hi_sig
= i
+ den_hi_sig
+ 1;
736 work
= num
[num_hi_sig
] * BASE
+ num
[num_hi_sig
- 1];
737 if (num
[num_hi_sig
] != den
[den_hi_sig
])
738 quo_est
= work
/ den
[den_hi_sig
];
742 /* Refine quo_est so it's usually correct, and at most one high. */
743 tmp
= work
- quo_est
* den
[den_hi_sig
];
745 && (den
[den_hi_sig
- 1] * quo_est
746 > (tmp
* BASE
+ num
[num_hi_sig
- 2])))
749 /* Try QUO_EST as the quotient digit, by multiplying the
750 divisor by QUO_EST and subtracting from the remaining dividend.
751 Keep in mind that QUO_EST is the I - 1st digit. */
754 for (j
= 0; j
<= den_hi_sig
; j
++)
756 work
= quo_est
* den
[j
] + carry
;
757 carry
= HIGHPART (work
);
758 work
= num
[i
+ j
] - LOWPART (work
);
759 num
[i
+ j
] = LOWPART (work
);
760 carry
+= HIGHPART (work
) != 0;
763 /* If quo_est was high by one, then num[i] went negative and
764 we need to correct things. */
765 if (num
[num_hi_sig
] < (HOST_WIDE_INT
) carry
)
768 carry
= 0; /* add divisor back in */
769 for (j
= 0; j
<= den_hi_sig
; j
++)
771 work
= num
[i
+ j
] + den
[j
] + carry
;
772 carry
= HIGHPART (work
);
773 num
[i
+ j
] = LOWPART (work
);
776 num
[num_hi_sig
] += carry
;
779 /* Store the quotient digit. */
784 decode (quo
, lquo
, hquo
);
787 /* If result is negative, make it so. */
789 neg_double (*lquo
, *hquo
, lquo
, hquo
);
791 /* Compute trial remainder: rem = num - (quo * den) */
792 mul_double (*lquo
, *hquo
, lden_orig
, hden_orig
, lrem
, hrem
);
793 neg_double (*lrem
, *hrem
, lrem
, hrem
);
794 add_double (lnum_orig
, hnum_orig
, *lrem
, *hrem
, lrem
, hrem
);
799 case TRUNC_MOD_EXPR
: /* round toward zero */
800 case EXACT_DIV_EXPR
: /* for this one, it shouldn't matter */
804 case FLOOR_MOD_EXPR
: /* round toward negative infinity */
805 if (quo_neg
&& (*lrem
!= 0 || *hrem
!= 0)) /* ratio < 0 && rem != 0 */
808 add_double (*lquo
, *hquo
, (HOST_WIDE_INT
) -1, (HOST_WIDE_INT
) -1,
816 case CEIL_MOD_EXPR
: /* round toward positive infinity */
817 if (!quo_neg
&& (*lrem
!= 0 || *hrem
!= 0)) /* ratio > 0 && rem != 0 */
819 add_double (*lquo
, *hquo
, (HOST_WIDE_INT
) 1, (HOST_WIDE_INT
) 0,
827 case ROUND_MOD_EXPR
: /* round to closest integer */
829 unsigned HOST_WIDE_INT labs_rem
= *lrem
;
830 HOST_WIDE_INT habs_rem
= *hrem
;
831 unsigned HOST_WIDE_INT labs_den
= lden
, ltwice
;
832 HOST_WIDE_INT habs_den
= hden
, htwice
;
834 /* Get absolute values. */
836 neg_double (*lrem
, *hrem
, &labs_rem
, &habs_rem
);
838 neg_double (lden
, hden
, &labs_den
, &habs_den
);
840 /* If (2 * abs (lrem) >= abs (lden)) */
841 mul_double ((HOST_WIDE_INT
) 2, (HOST_WIDE_INT
) 0,
842 labs_rem
, habs_rem
, <wice
, &htwice
);
844 if (((unsigned HOST_WIDE_INT
) habs_den
845 < (unsigned HOST_WIDE_INT
) htwice
)
846 || (((unsigned HOST_WIDE_INT
) habs_den
847 == (unsigned HOST_WIDE_INT
) htwice
)
848 && (labs_den
< ltwice
)))
852 add_double (*lquo
, *hquo
,
853 (HOST_WIDE_INT
) -1, (HOST_WIDE_INT
) -1, lquo
, hquo
);
856 add_double (*lquo
, *hquo
, (HOST_WIDE_INT
) 1, (HOST_WIDE_INT
) 0,
868 /* Compute true remainder: rem = num - (quo * den) */
869 mul_double (*lquo
, *hquo
, lden_orig
, hden_orig
, lrem
, hrem
);
870 neg_double (*lrem
, *hrem
, lrem
, hrem
);
871 add_double (lnum_orig
, hnum_orig
, *lrem
, *hrem
, lrem
, hrem
);
875 /* If ARG2 divides ARG1 with zero remainder, carries out the division
876 of type CODE and returns the quotient.
877 Otherwise returns NULL_TREE. */
880 div_if_zero_remainder (enum tree_code code
, const_tree arg1
, const_tree arg2
)
882 unsigned HOST_WIDE_INT int1l
, int2l
;
883 HOST_WIDE_INT int1h
, int2h
;
884 unsigned HOST_WIDE_INT quol
, reml
;
885 HOST_WIDE_INT quoh
, remh
;
886 tree type
= TREE_TYPE (arg1
);
887 int uns
= TYPE_UNSIGNED (type
);
889 int1l
= TREE_INT_CST_LOW (arg1
);
890 int1h
= TREE_INT_CST_HIGH (arg1
);
891 /* &obj[0] + -128 really should be compiled as &obj[-8] rather than
892 &obj[some_exotic_number]. */
893 if (POINTER_TYPE_P (type
))
896 type
= signed_type_for (type
);
897 fit_double_type (int1l
, int1h
, &int1l
, &int1h
,
901 fit_double_type (int1l
, int1h
, &int1l
, &int1h
, type
);
902 int2l
= TREE_INT_CST_LOW (arg2
);
903 int2h
= TREE_INT_CST_HIGH (arg2
);
905 div_and_round_double (code
, uns
, int1l
, int1h
, int2l
, int2h
,
906 &quol
, &quoh
, &reml
, &remh
);
907 if (remh
!= 0 || reml
!= 0)
910 return build_int_cst_wide (type
, quol
, quoh
);
913 /* This is nonzero if we should defer warnings about undefined
914 overflow. This facility exists because these warnings are a
915 special case. The code to estimate loop iterations does not want
916 to issue any warnings, since it works with expressions which do not
917 occur in user code. Various bits of cleanup code call fold(), but
918 only use the result if it has certain characteristics (e.g., is a
919 constant); that code only wants to issue a warning if the result is
922 static int fold_deferring_overflow_warnings
;
924 /* If a warning about undefined overflow is deferred, this is the
925 warning. Note that this may cause us to turn two warnings into
926 one, but that is fine since it is sufficient to only give one
927 warning per expression. */
929 static const char* fold_deferred_overflow_warning
;
931 /* If a warning about undefined overflow is deferred, this is the
932 level at which the warning should be emitted. */
934 static enum warn_strict_overflow_code fold_deferred_overflow_code
;
936 /* Start deferring overflow warnings. We could use a stack here to
937 permit nested calls, but at present it is not necessary. */
940 fold_defer_overflow_warnings (void)
942 ++fold_deferring_overflow_warnings
;
945 /* Stop deferring overflow warnings. If there is a pending warning,
946 and ISSUE is true, then issue the warning if appropriate. STMT is
947 the statement with which the warning should be associated (used for
948 location information); STMT may be NULL. CODE is the level of the
949 warning--a warn_strict_overflow_code value. This function will use
950 the smaller of CODE and the deferred code when deciding whether to
951 issue the warning. CODE may be zero to mean to always use the
955 fold_undefer_overflow_warnings (bool issue
, const_tree stmt
, int code
)
960 gcc_assert (fold_deferring_overflow_warnings
> 0);
961 --fold_deferring_overflow_warnings
;
962 if (fold_deferring_overflow_warnings
> 0)
964 if (fold_deferred_overflow_warning
!= NULL
966 && code
< (int) fold_deferred_overflow_code
)
967 fold_deferred_overflow_code
= code
;
971 warnmsg
= fold_deferred_overflow_warning
;
972 fold_deferred_overflow_warning
= NULL
;
974 if (!issue
|| warnmsg
== NULL
)
977 /* Use the smallest code level when deciding to issue the
979 if (code
== 0 || code
> (int) fold_deferred_overflow_code
)
980 code
= fold_deferred_overflow_code
;
982 if (!issue_strict_overflow_warning (code
))
985 if (stmt
== NULL_TREE
|| !expr_has_location (stmt
))
986 locus
= input_location
;
988 locus
= expr_location (stmt
);
989 warning (OPT_Wstrict_overflow
, "%H%s", &locus
, warnmsg
);
992 /* Stop deferring overflow warnings, ignoring any deferred
996 fold_undefer_and_ignore_overflow_warnings (void)
998 fold_undefer_overflow_warnings (false, NULL_TREE
, 0);
1001 /* Whether we are deferring overflow warnings. */
1004 fold_deferring_overflow_warnings_p (void)
1006 return fold_deferring_overflow_warnings
> 0;
1009 /* This is called when we fold something based on the fact that signed
1010 overflow is undefined. */
1013 fold_overflow_warning (const char* gmsgid
, enum warn_strict_overflow_code wc
)
1015 gcc_assert (!flag_wrapv
&& !flag_trapv
);
1016 if (fold_deferring_overflow_warnings
> 0)
1018 if (fold_deferred_overflow_warning
== NULL
1019 || wc
< fold_deferred_overflow_code
)
1021 fold_deferred_overflow_warning
= gmsgid
;
1022 fold_deferred_overflow_code
= wc
;
1025 else if (issue_strict_overflow_warning (wc
))
1026 warning (OPT_Wstrict_overflow
, gmsgid
);
1029 /* Return true if the built-in mathematical function specified by CODE
1030 is odd, i.e. -f(x) == f(-x). */
1033 negate_mathfn_p (enum built_in_function code
)
1037 CASE_FLT_FN (BUILT_IN_ASIN
):
1038 CASE_FLT_FN (BUILT_IN_ASINH
):
1039 CASE_FLT_FN (BUILT_IN_ATAN
):
1040 CASE_FLT_FN (BUILT_IN_ATANH
):
1041 CASE_FLT_FN (BUILT_IN_CASIN
):
1042 CASE_FLT_FN (BUILT_IN_CASINH
):
1043 CASE_FLT_FN (BUILT_IN_CATAN
):
1044 CASE_FLT_FN (BUILT_IN_CATANH
):
1045 CASE_FLT_FN (BUILT_IN_CBRT
):
1046 CASE_FLT_FN (BUILT_IN_CPROJ
):
1047 CASE_FLT_FN (BUILT_IN_CSIN
):
1048 CASE_FLT_FN (BUILT_IN_CSINH
):
1049 CASE_FLT_FN (BUILT_IN_CTAN
):
1050 CASE_FLT_FN (BUILT_IN_CTANH
):
1051 CASE_FLT_FN (BUILT_IN_ERF
):
1052 CASE_FLT_FN (BUILT_IN_LLROUND
):
1053 CASE_FLT_FN (BUILT_IN_LROUND
):
1054 CASE_FLT_FN (BUILT_IN_ROUND
):
1055 CASE_FLT_FN (BUILT_IN_SIN
):
1056 CASE_FLT_FN (BUILT_IN_SINH
):
1057 CASE_FLT_FN (BUILT_IN_TAN
):
1058 CASE_FLT_FN (BUILT_IN_TANH
):
1059 CASE_FLT_FN (BUILT_IN_TRUNC
):
1062 CASE_FLT_FN (BUILT_IN_LLRINT
):
1063 CASE_FLT_FN (BUILT_IN_LRINT
):
1064 CASE_FLT_FN (BUILT_IN_NEARBYINT
):
1065 CASE_FLT_FN (BUILT_IN_RINT
):
1066 return !flag_rounding_math
;
1074 /* Check whether we may negate an integer constant T without causing
1078 may_negate_without_overflow_p (const_tree t
)
1080 unsigned HOST_WIDE_INT val
;
1084 gcc_assert (TREE_CODE (t
) == INTEGER_CST
);
1086 type
= TREE_TYPE (t
);
1087 if (TYPE_UNSIGNED (type
))
1090 prec
= TYPE_PRECISION (type
);
1091 if (prec
> HOST_BITS_PER_WIDE_INT
)
1093 if (TREE_INT_CST_LOW (t
) != 0)
1095 prec
-= HOST_BITS_PER_WIDE_INT
;
1096 val
= TREE_INT_CST_HIGH (t
);
1099 val
= TREE_INT_CST_LOW (t
);
1100 if (prec
< HOST_BITS_PER_WIDE_INT
)
1101 val
&= ((unsigned HOST_WIDE_INT
) 1 << prec
) - 1;
1102 return val
!= ((unsigned HOST_WIDE_INT
) 1 << (prec
- 1));
1105 /* Determine whether an expression T can be cheaply negated using
1106 the function negate_expr without introducing undefined overflow. */
1109 negate_expr_p (tree t
)
1116 type
= TREE_TYPE (t
);
1118 STRIP_SIGN_NOPS (t
);
1119 switch (TREE_CODE (t
))
1122 if (TYPE_OVERFLOW_WRAPS (type
))
1125 /* Check that -CST will not overflow type. */
1126 return may_negate_without_overflow_p (t
);
1128 return (INTEGRAL_TYPE_P (type
)
1129 && TYPE_OVERFLOW_WRAPS (type
));
1137 return negate_expr_p (TREE_REALPART (t
))
1138 && negate_expr_p (TREE_IMAGPART (t
));
1141 return negate_expr_p (TREE_OPERAND (t
, 0))
1142 && negate_expr_p (TREE_OPERAND (t
, 1));
1145 return negate_expr_p (TREE_OPERAND (t
, 0));
1148 if (HONOR_SIGN_DEPENDENT_ROUNDING (TYPE_MODE (type
))
1149 || HONOR_SIGNED_ZEROS (TYPE_MODE (type
)))
1151 /* -(A + B) -> (-B) - A. */
1152 if (negate_expr_p (TREE_OPERAND (t
, 1))
1153 && reorder_operands_p (TREE_OPERAND (t
, 0),
1154 TREE_OPERAND (t
, 1)))
1156 /* -(A + B) -> (-A) - B. */
1157 return negate_expr_p (TREE_OPERAND (t
, 0));
1160 /* We can't turn -(A-B) into B-A when we honor signed zeros. */
1161 return !HONOR_SIGN_DEPENDENT_ROUNDING (TYPE_MODE (type
))
1162 && !HONOR_SIGNED_ZEROS (TYPE_MODE (type
))
1163 && reorder_operands_p (TREE_OPERAND (t
, 0),
1164 TREE_OPERAND (t
, 1));
1167 if (TYPE_UNSIGNED (TREE_TYPE (t
)))
1173 if (! HONOR_SIGN_DEPENDENT_ROUNDING (TYPE_MODE (TREE_TYPE (t
))))
1174 return negate_expr_p (TREE_OPERAND (t
, 1))
1175 || negate_expr_p (TREE_OPERAND (t
, 0));
1178 case TRUNC_DIV_EXPR
:
1179 case ROUND_DIV_EXPR
:
1180 case FLOOR_DIV_EXPR
:
1182 case EXACT_DIV_EXPR
:
1183 /* In general we can't negate A / B, because if A is INT_MIN and
1184 B is 1, we may turn this into INT_MIN / -1 which is undefined
1185 and actually traps on some architectures. But if overflow is
1186 undefined, we can negate, because - (INT_MIN / 1) is an
1188 if (INTEGRAL_TYPE_P (TREE_TYPE (t
))
1189 && !TYPE_OVERFLOW_UNDEFINED (TREE_TYPE (t
)))
1191 return negate_expr_p (TREE_OPERAND (t
, 1))
1192 || negate_expr_p (TREE_OPERAND (t
, 0));
1195 /* Negate -((double)float) as (double)(-float). */
1196 if (TREE_CODE (type
) == REAL_TYPE
)
1198 tree tem
= strip_float_extensions (t
);
1200 return negate_expr_p (tem
);
1205 /* Negate -f(x) as f(-x). */
1206 if (negate_mathfn_p (builtin_mathfn_code (t
)))
1207 return negate_expr_p (CALL_EXPR_ARG (t
, 0));
1211 /* Optimize -((int)x >> 31) into (unsigned)x >> 31. */
1212 if (TREE_CODE (TREE_OPERAND (t
, 1)) == INTEGER_CST
)
1214 tree op1
= TREE_OPERAND (t
, 1);
1215 if (TREE_INT_CST_HIGH (op1
) == 0
1216 && (unsigned HOST_WIDE_INT
) (TYPE_PRECISION (type
) - 1)
1217 == TREE_INT_CST_LOW (op1
))
1228 /* Given T, an expression, return a folded tree for -T or NULL_TREE, if no
1229 simplification is possible.
1230 If negate_expr_p would return true for T, NULL_TREE will never be
1234 fold_negate_expr (tree t
)
1236 tree type
= TREE_TYPE (t
);
1239 switch (TREE_CODE (t
))
1241 /* Convert - (~A) to A + 1. */
1243 if (INTEGRAL_TYPE_P (type
))
1244 return fold_build2 (PLUS_EXPR
, type
, TREE_OPERAND (t
, 0),
1245 build_int_cst (type
, 1));
1249 tem
= fold_negate_const (t
, type
);
1250 if (TREE_OVERFLOW (tem
) == TREE_OVERFLOW (t
)
1251 || !TYPE_OVERFLOW_TRAPS (type
))
1256 tem
= fold_negate_const (t
, type
);
1257 /* Two's complement FP formats, such as c4x, may overflow. */
1258 if (!TREE_OVERFLOW (tem
) || !flag_trapping_math
)
1263 tem
= fold_negate_const (t
, type
);
1268 tree rpart
= negate_expr (TREE_REALPART (t
));
1269 tree ipart
= negate_expr (TREE_IMAGPART (t
));
1271 if ((TREE_CODE (rpart
) == REAL_CST
1272 && TREE_CODE (ipart
) == REAL_CST
)
1273 || (TREE_CODE (rpart
) == INTEGER_CST
1274 && TREE_CODE (ipart
) == INTEGER_CST
))
1275 return build_complex (type
, rpart
, ipart
);
1280 if (negate_expr_p (t
))
1281 return fold_build2 (COMPLEX_EXPR
, type
,
1282 fold_negate_expr (TREE_OPERAND (t
, 0)),
1283 fold_negate_expr (TREE_OPERAND (t
, 1)));
1287 if (negate_expr_p (t
))
1288 return fold_build1 (CONJ_EXPR
, type
,
1289 fold_negate_expr (TREE_OPERAND (t
, 0)));
1293 return TREE_OPERAND (t
, 0);
1296 if (!HONOR_SIGN_DEPENDENT_ROUNDING (TYPE_MODE (type
))
1297 && !HONOR_SIGNED_ZEROS (TYPE_MODE (type
)))
1299 /* -(A + B) -> (-B) - A. */
1300 if (negate_expr_p (TREE_OPERAND (t
, 1))
1301 && reorder_operands_p (TREE_OPERAND (t
, 0),
1302 TREE_OPERAND (t
, 1)))
1304 tem
= negate_expr (TREE_OPERAND (t
, 1));
1305 return fold_build2 (MINUS_EXPR
, type
,
1306 tem
, TREE_OPERAND (t
, 0));
1309 /* -(A + B) -> (-A) - B. */
1310 if (negate_expr_p (TREE_OPERAND (t
, 0)))
1312 tem
= negate_expr (TREE_OPERAND (t
, 0));
1313 return fold_build2 (MINUS_EXPR
, type
,
1314 tem
, TREE_OPERAND (t
, 1));
1320 /* - (A - B) -> B - A */
1321 if (!HONOR_SIGN_DEPENDENT_ROUNDING (TYPE_MODE (type
))
1322 && !HONOR_SIGNED_ZEROS (TYPE_MODE (type
))
1323 && reorder_operands_p (TREE_OPERAND (t
, 0), TREE_OPERAND (t
, 1)))
1324 return fold_build2 (MINUS_EXPR
, type
,
1325 TREE_OPERAND (t
, 1), TREE_OPERAND (t
, 0));
1329 if (TYPE_UNSIGNED (type
))
1335 if (! HONOR_SIGN_DEPENDENT_ROUNDING (TYPE_MODE (type
)))
1337 tem
= TREE_OPERAND (t
, 1);
1338 if (negate_expr_p (tem
))
1339 return fold_build2 (TREE_CODE (t
), type
,
1340 TREE_OPERAND (t
, 0), negate_expr (tem
));
1341 tem
= TREE_OPERAND (t
, 0);
1342 if (negate_expr_p (tem
))
1343 return fold_build2 (TREE_CODE (t
), type
,
1344 negate_expr (tem
), TREE_OPERAND (t
, 1));
1348 case TRUNC_DIV_EXPR
:
1349 case ROUND_DIV_EXPR
:
1350 case FLOOR_DIV_EXPR
:
1352 case EXACT_DIV_EXPR
:
1353 /* In general we can't negate A / B, because if A is INT_MIN and
1354 B is 1, we may turn this into INT_MIN / -1 which is undefined
1355 and actually traps on some architectures. But if overflow is
1356 undefined, we can negate, because - (INT_MIN / 1) is an
1358 if (!INTEGRAL_TYPE_P (type
) || TYPE_OVERFLOW_UNDEFINED (type
))
1360 const char * const warnmsg
= G_("assuming signed overflow does not "
1361 "occur when negating a division");
1362 tem
= TREE_OPERAND (t
, 1);
1363 if (negate_expr_p (tem
))
1365 if (INTEGRAL_TYPE_P (type
)
1366 && (TREE_CODE (tem
) != INTEGER_CST
1367 || integer_onep (tem
)))
1368 fold_overflow_warning (warnmsg
, WARN_STRICT_OVERFLOW_MISC
);
1369 return fold_build2 (TREE_CODE (t
), type
,
1370 TREE_OPERAND (t
, 0), negate_expr (tem
));
1372 tem
= TREE_OPERAND (t
, 0);
1373 if (negate_expr_p (tem
))
1375 if (INTEGRAL_TYPE_P (type
)
1376 && (TREE_CODE (tem
) != INTEGER_CST
1377 || tree_int_cst_equal (tem
, TYPE_MIN_VALUE (type
))))
1378 fold_overflow_warning (warnmsg
, WARN_STRICT_OVERFLOW_MISC
);
1379 return fold_build2 (TREE_CODE (t
), type
,
1380 negate_expr (tem
), TREE_OPERAND (t
, 1));
1386 /* Convert -((double)float) into (double)(-float). */
1387 if (TREE_CODE (type
) == REAL_TYPE
)
1389 tem
= strip_float_extensions (t
);
1390 if (tem
!= t
&& negate_expr_p (tem
))
1391 return fold_convert (type
, negate_expr (tem
));
1396 /* Negate -f(x) as f(-x). */
1397 if (negate_mathfn_p (builtin_mathfn_code (t
))
1398 && negate_expr_p (CALL_EXPR_ARG (t
, 0)))
1402 fndecl
= get_callee_fndecl (t
);
1403 arg
= negate_expr (CALL_EXPR_ARG (t
, 0));
1404 return build_call_expr (fndecl
, 1, arg
);
1409 /* Optimize -((int)x >> 31) into (unsigned)x >> 31. */
1410 if (TREE_CODE (TREE_OPERAND (t
, 1)) == INTEGER_CST
)
1412 tree op1
= TREE_OPERAND (t
, 1);
1413 if (TREE_INT_CST_HIGH (op1
) == 0
1414 && (unsigned HOST_WIDE_INT
) (TYPE_PRECISION (type
) - 1)
1415 == TREE_INT_CST_LOW (op1
))
1417 tree ntype
= TYPE_UNSIGNED (type
)
1418 ? signed_type_for (type
)
1419 : unsigned_type_for (type
);
1420 tree temp
= fold_convert (ntype
, TREE_OPERAND (t
, 0));
1421 temp
= fold_build2 (RSHIFT_EXPR
, ntype
, temp
, op1
);
1422 return fold_convert (type
, temp
);
1434 /* Like fold_negate_expr, but return a NEGATE_EXPR tree, if T can not be
1435 negated in a simpler way. Also allow for T to be NULL_TREE, in which case
1436 return NULL_TREE. */
1439 negate_expr (tree t
)
1446 type
= TREE_TYPE (t
);
1447 STRIP_SIGN_NOPS (t
);
1449 tem
= fold_negate_expr (t
);
1451 tem
= build1 (NEGATE_EXPR
, TREE_TYPE (t
), t
);
1452 return fold_convert (type
, tem
);
1455 /* Split a tree IN into a constant, literal and variable parts that could be
1456 combined with CODE to make IN. "constant" means an expression with
1457 TREE_CONSTANT but that isn't an actual constant. CODE must be a
1458 commutative arithmetic operation. Store the constant part into *CONP,
1459 the literal in *LITP and return the variable part. If a part isn't
1460 present, set it to null. If the tree does not decompose in this way,
1461 return the entire tree as the variable part and the other parts as null.
1463 If CODE is PLUS_EXPR we also split trees that use MINUS_EXPR. In that
1464 case, we negate an operand that was subtracted. Except if it is a
1465 literal for which we use *MINUS_LITP instead.
1467 If NEGATE_P is true, we are negating all of IN, again except a literal
1468 for which we use *MINUS_LITP instead.
1470 If IN is itself a literal or constant, return it as appropriate.
1472 Note that we do not guarantee that any of the three values will be the
1473 same type as IN, but they will have the same signedness and mode. */
1476 split_tree (tree in
, enum tree_code code
, tree
*conp
, tree
*litp
,
1477 tree
*minus_litp
, int negate_p
)
1485 /* Strip any conversions that don't change the machine mode or signedness. */
1486 STRIP_SIGN_NOPS (in
);
1488 if (TREE_CODE (in
) == INTEGER_CST
|| TREE_CODE (in
) == REAL_CST
1489 || TREE_CODE (in
) == FIXED_CST
)
1491 else if (TREE_CODE (in
) == code
1492 || (! FLOAT_TYPE_P (TREE_TYPE (in
))
1493 && ! SAT_FIXED_POINT_TYPE_P (TREE_TYPE (in
))
1494 /* We can associate addition and subtraction together (even
1495 though the C standard doesn't say so) for integers because
1496 the value is not affected. For reals, the value might be
1497 affected, so we can't. */
1498 && ((code
== PLUS_EXPR
&& TREE_CODE (in
) == MINUS_EXPR
)
1499 || (code
== MINUS_EXPR
&& TREE_CODE (in
) == PLUS_EXPR
))))
1501 tree op0
= TREE_OPERAND (in
, 0);
1502 tree op1
= TREE_OPERAND (in
, 1);
1503 int neg1_p
= TREE_CODE (in
) == MINUS_EXPR
;
1504 int neg_litp_p
= 0, neg_conp_p
= 0, neg_var_p
= 0;
1506 /* First see if either of the operands is a literal, then a constant. */
1507 if (TREE_CODE (op0
) == INTEGER_CST
|| TREE_CODE (op0
) == REAL_CST
1508 || TREE_CODE (op0
) == FIXED_CST
)
1509 *litp
= op0
, op0
= 0;
1510 else if (TREE_CODE (op1
) == INTEGER_CST
|| TREE_CODE (op1
) == REAL_CST
1511 || TREE_CODE (op1
) == FIXED_CST
)
1512 *litp
= op1
, neg_litp_p
= neg1_p
, op1
= 0;
1514 if (op0
!= 0 && TREE_CONSTANT (op0
))
1515 *conp
= op0
, op0
= 0;
1516 else if (op1
!= 0 && TREE_CONSTANT (op1
))
1517 *conp
= op1
, neg_conp_p
= neg1_p
, op1
= 0;
1519 /* If we haven't dealt with either operand, this is not a case we can
1520 decompose. Otherwise, VAR is either of the ones remaining, if any. */
1521 if (op0
!= 0 && op1
!= 0)
1526 var
= op1
, neg_var_p
= neg1_p
;
1528 /* Now do any needed negations. */
1530 *minus_litp
= *litp
, *litp
= 0;
1532 *conp
= negate_expr (*conp
);
1534 var
= negate_expr (var
);
1536 else if (TREE_CONSTANT (in
))
1544 *minus_litp
= *litp
, *litp
= 0;
1545 else if (*minus_litp
)
1546 *litp
= *minus_litp
, *minus_litp
= 0;
1547 *conp
= negate_expr (*conp
);
1548 var
= negate_expr (var
);
1554 /* Re-associate trees split by the above function. T1 and T2 are either
1555 expressions to associate or null. Return the new expression, if any. If
1556 we build an operation, do it in TYPE and with CODE. */
1559 associate_trees (tree t1
, tree t2
, enum tree_code code
, tree type
)
1566 /* If either input is CODE, a PLUS_EXPR, or a MINUS_EXPR, don't
1567 try to fold this since we will have infinite recursion. But do
1568 deal with any NEGATE_EXPRs. */
1569 if (TREE_CODE (t1
) == code
|| TREE_CODE (t2
) == code
1570 || TREE_CODE (t1
) == MINUS_EXPR
|| TREE_CODE (t2
) == MINUS_EXPR
)
1572 if (code
== PLUS_EXPR
)
1574 if (TREE_CODE (t1
) == NEGATE_EXPR
)
1575 return build2 (MINUS_EXPR
, type
, fold_convert (type
, t2
),
1576 fold_convert (type
, TREE_OPERAND (t1
, 0)));
1577 else if (TREE_CODE (t2
) == NEGATE_EXPR
)
1578 return build2 (MINUS_EXPR
, type
, fold_convert (type
, t1
),
1579 fold_convert (type
, TREE_OPERAND (t2
, 0)));
1580 else if (integer_zerop (t2
))
1581 return fold_convert (type
, t1
);
1583 else if (code
== MINUS_EXPR
)
1585 if (integer_zerop (t2
))
1586 return fold_convert (type
, t1
);
1589 return build2 (code
, type
, fold_convert (type
, t1
),
1590 fold_convert (type
, t2
));
1593 return fold_build2 (code
, type
, fold_convert (type
, t1
),
1594 fold_convert (type
, t2
));
1597 /* Check whether TYPE1 and TYPE2 are equivalent integer types, suitable
1598 for use in int_const_binop, size_binop and size_diffop. */
1601 int_binop_types_match_p (enum tree_code code
, const_tree type1
, const_tree type2
)
1603 if (TREE_CODE (type1
) != INTEGER_TYPE
&& !POINTER_TYPE_P (type1
))
1605 if (TREE_CODE (type2
) != INTEGER_TYPE
&& !POINTER_TYPE_P (type2
))
1620 return TYPE_UNSIGNED (type1
) == TYPE_UNSIGNED (type2
)
1621 && TYPE_PRECISION (type1
) == TYPE_PRECISION (type2
)
1622 && TYPE_MODE (type1
) == TYPE_MODE (type2
);
1626 /* Combine two integer constants ARG1 and ARG2 under operation CODE
1627 to produce a new constant. Return NULL_TREE if we don't know how
1628 to evaluate CODE at compile-time.
1630 If NOTRUNC is nonzero, do not truncate the result to fit the data type. */
1633 int_const_binop (enum tree_code code
, const_tree arg1
, const_tree arg2
, int notrunc
)
1635 unsigned HOST_WIDE_INT int1l
, int2l
;
1636 HOST_WIDE_INT int1h
, int2h
;
1637 unsigned HOST_WIDE_INT low
;
1639 unsigned HOST_WIDE_INT garbagel
;
1640 HOST_WIDE_INT garbageh
;
1642 tree type
= TREE_TYPE (arg1
);
1643 int uns
= TYPE_UNSIGNED (type
);
1645 = (TREE_CODE (type
) == INTEGER_TYPE
&& TYPE_IS_SIZETYPE (type
));
1648 int1l
= TREE_INT_CST_LOW (arg1
);
1649 int1h
= TREE_INT_CST_HIGH (arg1
);
1650 int2l
= TREE_INT_CST_LOW (arg2
);
1651 int2h
= TREE_INT_CST_HIGH (arg2
);
1656 low
= int1l
| int2l
, hi
= int1h
| int2h
;
1660 low
= int1l
^ int2l
, hi
= int1h
^ int2h
;
1664 low
= int1l
& int2l
, hi
= int1h
& int2h
;
1670 /* It's unclear from the C standard whether shifts can overflow.
1671 The following code ignores overflow; perhaps a C standard
1672 interpretation ruling is needed. */
1673 lshift_double (int1l
, int1h
, int2l
, TYPE_PRECISION (type
),
1680 lrotate_double (int1l
, int1h
, int2l
, TYPE_PRECISION (type
),
1685 overflow
= add_double (int1l
, int1h
, int2l
, int2h
, &low
, &hi
);
1689 neg_double (int2l
, int2h
, &low
, &hi
);
1690 add_double (int1l
, int1h
, low
, hi
, &low
, &hi
);
1691 overflow
= OVERFLOW_SUM_SIGN (hi
, int2h
, int1h
);
1695 overflow
= mul_double (int1l
, int1h
, int2l
, int2h
, &low
, &hi
);
1698 case TRUNC_DIV_EXPR
:
1699 case FLOOR_DIV_EXPR
: case CEIL_DIV_EXPR
:
1700 case EXACT_DIV_EXPR
:
1701 /* This is a shortcut for a common special case. */
1702 if (int2h
== 0 && (HOST_WIDE_INT
) int2l
> 0
1703 && !TREE_OVERFLOW (arg1
)
1704 && !TREE_OVERFLOW (arg2
)
1705 && int1h
== 0 && (HOST_WIDE_INT
) int1l
>= 0)
1707 if (code
== CEIL_DIV_EXPR
)
1710 low
= int1l
/ int2l
, hi
= 0;
1714 /* ... fall through ... */
1716 case ROUND_DIV_EXPR
:
1717 if (int2h
== 0 && int2l
== 0)
1719 if (int2h
== 0 && int2l
== 1)
1721 low
= int1l
, hi
= int1h
;
1724 if (int1l
== int2l
&& int1h
== int2h
1725 && ! (int1l
== 0 && int1h
== 0))
1730 overflow
= div_and_round_double (code
, uns
, int1l
, int1h
, int2l
, int2h
,
1731 &low
, &hi
, &garbagel
, &garbageh
);
1734 case TRUNC_MOD_EXPR
:
1735 case FLOOR_MOD_EXPR
: case CEIL_MOD_EXPR
:
1736 /* This is a shortcut for a common special case. */
1737 if (int2h
== 0 && (HOST_WIDE_INT
) int2l
> 0
1738 && !TREE_OVERFLOW (arg1
)
1739 && !TREE_OVERFLOW (arg2
)
1740 && int1h
== 0 && (HOST_WIDE_INT
) int1l
>= 0)
1742 if (code
== CEIL_MOD_EXPR
)
1744 low
= int1l
% int2l
, hi
= 0;
1748 /* ... fall through ... */
1750 case ROUND_MOD_EXPR
:
1751 if (int2h
== 0 && int2l
== 0)
1753 overflow
= div_and_round_double (code
, uns
,
1754 int1l
, int1h
, int2l
, int2h
,
1755 &garbagel
, &garbageh
, &low
, &hi
);
1761 low
= (((unsigned HOST_WIDE_INT
) int1h
1762 < (unsigned HOST_WIDE_INT
) int2h
)
1763 || (((unsigned HOST_WIDE_INT
) int1h
1764 == (unsigned HOST_WIDE_INT
) int2h
)
1767 low
= (int1h
< int2h
1768 || (int1h
== int2h
&& int1l
< int2l
));
1770 if (low
== (code
== MIN_EXPR
))
1771 low
= int1l
, hi
= int1h
;
1773 low
= int2l
, hi
= int2h
;
1782 t
= build_int_cst_wide (TREE_TYPE (arg1
), low
, hi
);
1784 /* Propagate overflow flags ourselves. */
1785 if (((!uns
|| is_sizetype
) && overflow
)
1786 | TREE_OVERFLOW (arg1
) | TREE_OVERFLOW (arg2
))
1789 TREE_OVERFLOW (t
) = 1;
1793 t
= force_fit_type_double (TREE_TYPE (arg1
), low
, hi
, 1,
1794 ((!uns
|| is_sizetype
) && overflow
)
1795 | TREE_OVERFLOW (arg1
) | TREE_OVERFLOW (arg2
));
1800 /* Combine two constants ARG1 and ARG2 under operation CODE to produce a new
1801 constant. We assume ARG1 and ARG2 have the same data type, or at least
1802 are the same kind of constant and the same machine mode. Return zero if
1803 combining the constants is not allowed in the current operating mode.
1805 If NOTRUNC is nonzero, do not truncate the result to fit the data type. */
1808 const_binop (enum tree_code code
, tree arg1
, tree arg2
, int notrunc
)
1810 /* Sanity check for the recursive cases. */
1817 if (TREE_CODE (arg1
) == INTEGER_CST
)
1818 return int_const_binop (code
, arg1
, arg2
, notrunc
);
1820 if (TREE_CODE (arg1
) == REAL_CST
)
1822 enum machine_mode mode
;
1825 REAL_VALUE_TYPE value
;
1826 REAL_VALUE_TYPE result
;
1830 /* The following codes are handled by real_arithmetic. */
1845 d1
= TREE_REAL_CST (arg1
);
1846 d2
= TREE_REAL_CST (arg2
);
1848 type
= TREE_TYPE (arg1
);
1849 mode
= TYPE_MODE (type
);
1851 /* Don't perform operation if we honor signaling NaNs and
1852 either operand is a NaN. */
1853 if (HONOR_SNANS (mode
)
1854 && (REAL_VALUE_ISNAN (d1
) || REAL_VALUE_ISNAN (d2
)))
1857 /* Don't perform operation if it would raise a division
1858 by zero exception. */
1859 if (code
== RDIV_EXPR
1860 && REAL_VALUES_EQUAL (d2
, dconst0
)
1861 && (flag_trapping_math
|| ! MODE_HAS_INFINITIES (mode
)))
1864 /* If either operand is a NaN, just return it. Otherwise, set up
1865 for floating-point trap; we return an overflow. */
1866 if (REAL_VALUE_ISNAN (d1
))
1868 else if (REAL_VALUE_ISNAN (d2
))
1871 inexact
= real_arithmetic (&value
, code
, &d1
, &d2
);
1872 real_convert (&result
, mode
, &value
);
1874 /* Don't constant fold this floating point operation if
1875 the result has overflowed and flag_trapping_math. */
1876 if (flag_trapping_math
1877 && MODE_HAS_INFINITIES (mode
)
1878 && REAL_VALUE_ISINF (result
)
1879 && !REAL_VALUE_ISINF (d1
)
1880 && !REAL_VALUE_ISINF (d2
))
1883 /* Don't constant fold this floating point operation if the
1884 result may dependent upon the run-time rounding mode and
1885 flag_rounding_math is set, or if GCC's software emulation
1886 is unable to accurately represent the result. */
1887 if ((flag_rounding_math
1888 || (REAL_MODE_FORMAT_COMPOSITE_P (mode
)
1889 && !flag_unsafe_math_optimizations
))
1890 && (inexact
|| !real_identical (&result
, &value
)))
1893 t
= build_real (type
, result
);
1895 TREE_OVERFLOW (t
) = TREE_OVERFLOW (arg1
) | TREE_OVERFLOW (arg2
);
1899 if (TREE_CODE (arg1
) == FIXED_CST
)
1901 FIXED_VALUE_TYPE f1
;
1902 FIXED_VALUE_TYPE f2
;
1903 FIXED_VALUE_TYPE result
;
1908 /* The following codes are handled by fixed_arithmetic. */
1914 case TRUNC_DIV_EXPR
:
1915 f2
= TREE_FIXED_CST (arg2
);
1920 f2
.data
.high
= TREE_INT_CST_HIGH (arg2
);
1921 f2
.data
.low
= TREE_INT_CST_LOW (arg2
);
1929 f1
= TREE_FIXED_CST (arg1
);
1930 type
= TREE_TYPE (arg1
);
1931 sat_p
= TYPE_SATURATING (type
);
1932 overflow_p
= fixed_arithmetic (&result
, code
, &f1
, &f2
, sat_p
);
1933 t
= build_fixed (type
, result
);
1934 /* Propagate overflow flags. */
1935 if (overflow_p
| TREE_OVERFLOW (arg1
) | TREE_OVERFLOW (arg2
))
1937 TREE_OVERFLOW (t
) = 1;
1938 TREE_CONSTANT_OVERFLOW (t
) = 1;
1940 else if (TREE_CONSTANT_OVERFLOW (arg1
) | TREE_CONSTANT_OVERFLOW (arg2
))
1941 TREE_CONSTANT_OVERFLOW (t
) = 1;
1945 if (TREE_CODE (arg1
) == COMPLEX_CST
)
1947 tree type
= TREE_TYPE (arg1
);
1948 tree r1
= TREE_REALPART (arg1
);
1949 tree i1
= TREE_IMAGPART (arg1
);
1950 tree r2
= TREE_REALPART (arg2
);
1951 tree i2
= TREE_IMAGPART (arg2
);
1958 real
= const_binop (code
, r1
, r2
, notrunc
);
1959 imag
= const_binop (code
, i1
, i2
, notrunc
);
1963 real
= const_binop (MINUS_EXPR
,
1964 const_binop (MULT_EXPR
, r1
, r2
, notrunc
),
1965 const_binop (MULT_EXPR
, i1
, i2
, notrunc
),
1967 imag
= const_binop (PLUS_EXPR
,
1968 const_binop (MULT_EXPR
, r1
, i2
, notrunc
),
1969 const_binop (MULT_EXPR
, i1
, r2
, notrunc
),
1976 = const_binop (PLUS_EXPR
,
1977 const_binop (MULT_EXPR
, r2
, r2
, notrunc
),
1978 const_binop (MULT_EXPR
, i2
, i2
, notrunc
),
1981 = const_binop (PLUS_EXPR
,
1982 const_binop (MULT_EXPR
, r1
, r2
, notrunc
),
1983 const_binop (MULT_EXPR
, i1
, i2
, notrunc
),
1986 = const_binop (MINUS_EXPR
,
1987 const_binop (MULT_EXPR
, i1
, r2
, notrunc
),
1988 const_binop (MULT_EXPR
, r1
, i2
, notrunc
),
1991 if (INTEGRAL_TYPE_P (TREE_TYPE (r1
)))
1992 code
= TRUNC_DIV_EXPR
;
1994 real
= const_binop (code
, t1
, magsquared
, notrunc
);
1995 imag
= const_binop (code
, t2
, magsquared
, notrunc
);
2004 return build_complex (type
, real
, imag
);
2010 /* Create a size type INT_CST node with NUMBER sign extended. KIND
2011 indicates which particular sizetype to create. */
2014 size_int_kind (HOST_WIDE_INT number
, enum size_type_kind kind
)
2016 return build_int_cst (sizetype_tab
[(int) kind
], number
);
2019 /* Combine operands OP1 and OP2 with arithmetic operation CODE. CODE
2020 is a tree code. The type of the result is taken from the operands.
2021 Both must be equivalent integer types, ala int_binop_types_match_p.
2022 If the operands are constant, so is the result. */
2025 size_binop (enum tree_code code
, tree arg0
, tree arg1
)
2027 tree type
= TREE_TYPE (arg0
);
2029 if (arg0
== error_mark_node
|| arg1
== error_mark_node
)
2030 return error_mark_node
;
2032 gcc_assert (int_binop_types_match_p (code
, TREE_TYPE (arg0
),
2035 /* Handle the special case of two integer constants faster. */
2036 if (TREE_CODE (arg0
) == INTEGER_CST
&& TREE_CODE (arg1
) == INTEGER_CST
)
2038 /* And some specific cases even faster than that. */
2039 if (code
== PLUS_EXPR
)
2041 if (integer_zerop (arg0
) && !TREE_OVERFLOW (arg0
))
2043 if (integer_zerop (arg1
) && !TREE_OVERFLOW (arg1
))
2046 else if (code
== MINUS_EXPR
)
2048 if (integer_zerop (arg1
) && !TREE_OVERFLOW (arg1
))
2051 else if (code
== MULT_EXPR
)
2053 if (integer_onep (arg0
) && !TREE_OVERFLOW (arg0
))
2057 /* Handle general case of two integer constants. */
2058 return int_const_binop (code
, arg0
, arg1
, 0);
2061 return fold_build2 (code
, type
, arg0
, arg1
);
2064 /* Given two values, either both of sizetype or both of bitsizetype,
2065 compute the difference between the two values. Return the value
2066 in signed type corresponding to the type of the operands. */
2069 size_diffop (tree arg0
, tree arg1
)
2071 tree type
= TREE_TYPE (arg0
);
2074 gcc_assert (int_binop_types_match_p (MINUS_EXPR
, TREE_TYPE (arg0
),
2077 /* If the type is already signed, just do the simple thing. */
2078 if (!TYPE_UNSIGNED (type
))
2079 return size_binop (MINUS_EXPR
, arg0
, arg1
);
2081 if (type
== sizetype
)
2083 else if (type
== bitsizetype
)
2084 ctype
= sbitsizetype
;
2086 ctype
= signed_type_for (type
);
2088 /* If either operand is not a constant, do the conversions to the signed
2089 type and subtract. The hardware will do the right thing with any
2090 overflow in the subtraction. */
2091 if (TREE_CODE (arg0
) != INTEGER_CST
|| TREE_CODE (arg1
) != INTEGER_CST
)
2092 return size_binop (MINUS_EXPR
, fold_convert (ctype
, arg0
),
2093 fold_convert (ctype
, arg1
));
2095 /* If ARG0 is larger than ARG1, subtract and return the result in CTYPE.
2096 Otherwise, subtract the other way, convert to CTYPE (we know that can't
2097 overflow) and negate (which can't either). Special-case a result
2098 of zero while we're here. */
2099 if (tree_int_cst_equal (arg0
, arg1
))
2100 return build_int_cst (ctype
, 0);
2101 else if (tree_int_cst_lt (arg1
, arg0
))
2102 return fold_convert (ctype
, size_binop (MINUS_EXPR
, arg0
, arg1
));
2104 return size_binop (MINUS_EXPR
, build_int_cst (ctype
, 0),
2105 fold_convert (ctype
, size_binop (MINUS_EXPR
,
2109 /* A subroutine of fold_convert_const handling conversions of an
2110 INTEGER_CST to another integer type. */
2113 fold_convert_const_int_from_int (tree type
, const_tree arg1
)
2117 /* Given an integer constant, make new constant with new type,
2118 appropriately sign-extended or truncated. */
2119 t
= force_fit_type_double (type
, TREE_INT_CST_LOW (arg1
),
2120 TREE_INT_CST_HIGH (arg1
),
2121 /* Don't set the overflow when
2122 converting a pointer */
2123 !POINTER_TYPE_P (TREE_TYPE (arg1
)),
2124 (TREE_INT_CST_HIGH (arg1
) < 0
2125 && (TYPE_UNSIGNED (type
)
2126 < TYPE_UNSIGNED (TREE_TYPE (arg1
))))
2127 | TREE_OVERFLOW (arg1
));
2132 /* A subroutine of fold_convert_const handling conversions a REAL_CST
2133 to an integer type. */
2136 fold_convert_const_int_from_real (enum tree_code code
, tree type
, const_tree arg1
)
2141 /* The following code implements the floating point to integer
2142 conversion rules required by the Java Language Specification,
2143 that IEEE NaNs are mapped to zero and values that overflow
2144 the target precision saturate, i.e. values greater than
2145 INT_MAX are mapped to INT_MAX, and values less than INT_MIN
2146 are mapped to INT_MIN. These semantics are allowed by the
2147 C and C++ standards that simply state that the behavior of
2148 FP-to-integer conversion is unspecified upon overflow. */
2150 HOST_WIDE_INT high
, low
;
2152 REAL_VALUE_TYPE x
= TREE_REAL_CST (arg1
);
2156 case FIX_TRUNC_EXPR
:
2157 real_trunc (&r
, VOIDmode
, &x
);
2164 /* If R is NaN, return zero and show we have an overflow. */
2165 if (REAL_VALUE_ISNAN (r
))
2172 /* See if R is less than the lower bound or greater than the
2177 tree lt
= TYPE_MIN_VALUE (type
);
2178 REAL_VALUE_TYPE l
= real_value_from_int_cst (NULL_TREE
, lt
);
2179 if (REAL_VALUES_LESS (r
, l
))
2182 high
= TREE_INT_CST_HIGH (lt
);
2183 low
= TREE_INT_CST_LOW (lt
);
2189 tree ut
= TYPE_MAX_VALUE (type
);
2192 REAL_VALUE_TYPE u
= real_value_from_int_cst (NULL_TREE
, ut
);
2193 if (REAL_VALUES_LESS (u
, r
))
2196 high
= TREE_INT_CST_HIGH (ut
);
2197 low
= TREE_INT_CST_LOW (ut
);
2203 REAL_VALUE_TO_INT (&low
, &high
, r
);
2205 t
= force_fit_type_double (type
, low
, high
, -1,
2206 overflow
| TREE_OVERFLOW (arg1
));
2210 /* A subroutine of fold_convert_const handling conversions of a
2211 FIXED_CST to an integer type. */
2214 fold_convert_const_int_from_fixed (tree type
, const_tree arg1
)
2217 double_int temp
, temp_trunc
;
2220 /* Right shift FIXED_CST to temp by fbit. */
2221 temp
= TREE_FIXED_CST (arg1
).data
;
2222 mode
= TREE_FIXED_CST (arg1
).mode
;
2223 if (GET_MODE_FBIT (mode
) < 2 * HOST_BITS_PER_WIDE_INT
)
2225 lshift_double (temp
.low
, temp
.high
,
2226 - GET_MODE_FBIT (mode
), 2 * HOST_BITS_PER_WIDE_INT
,
2227 &temp
.low
, &temp
.high
, SIGNED_FIXED_POINT_MODE_P (mode
));
2229 /* Left shift temp to temp_trunc by fbit. */
2230 lshift_double (temp
.low
, temp
.high
,
2231 GET_MODE_FBIT (mode
), 2 * HOST_BITS_PER_WIDE_INT
,
2232 &temp_trunc
.low
, &temp_trunc
.high
,
2233 SIGNED_FIXED_POINT_MODE_P (mode
));
2240 temp_trunc
.high
= 0;
2243 /* If FIXED_CST is negative, we need to round the value toward 0.
2244 By checking if the fractional bits are not zero to add 1 to temp. */
2245 if (SIGNED_FIXED_POINT_MODE_P (mode
) && temp_trunc
.high
< 0
2246 && !double_int_equal_p (TREE_FIXED_CST (arg1
).data
, temp_trunc
))
2251 temp
= double_int_add (temp
, one
);
2254 /* Given a fixed-point constant, make new constant with new type,
2255 appropriately sign-extended or truncated. */
2256 t
= force_fit_type_double (type
, temp
.low
, temp
.high
, -1,
2258 && (TYPE_UNSIGNED (type
)
2259 < TYPE_UNSIGNED (TREE_TYPE (arg1
))))
2260 | TREE_OVERFLOW (arg1
));
2265 /* A subroutine of fold_convert_const handling conversions a REAL_CST
2266 to another floating point type. */
2269 fold_convert_const_real_from_real (tree type
, const_tree arg1
)
2271 REAL_VALUE_TYPE value
;
2274 real_convert (&value
, TYPE_MODE (type
), &TREE_REAL_CST (arg1
));
2275 t
= build_real (type
, value
);
2277 TREE_OVERFLOW (t
) = TREE_OVERFLOW (arg1
);
2281 /* A subroutine of fold_convert_const handling conversions a FIXED_CST
2282 to a floating point type. */
2285 fold_convert_const_real_from_fixed (tree type
, const_tree arg1
)
2287 REAL_VALUE_TYPE value
;
2290 real_convert_from_fixed (&value
, TYPE_MODE (type
), &TREE_FIXED_CST (arg1
));
2291 t
= build_real (type
, value
);
2293 TREE_OVERFLOW (t
) = TREE_OVERFLOW (arg1
);
2294 TREE_CONSTANT_OVERFLOW (t
)
2295 = TREE_OVERFLOW (t
) | TREE_CONSTANT_OVERFLOW (arg1
);
2299 /* A subroutine of fold_convert_const handling conversions a FIXED_CST
2300 to another fixed-point type. */
2303 fold_convert_const_fixed_from_fixed (tree type
, const_tree arg1
)
2305 FIXED_VALUE_TYPE value
;
2309 overflow_p
= fixed_convert (&value
, TYPE_MODE (type
), &TREE_FIXED_CST (arg1
),
2310 TYPE_SATURATING (type
));
2311 t
= build_fixed (type
, value
);
2313 /* Propagate overflow flags. */
2314 if (overflow_p
| TREE_OVERFLOW (arg1
))
2316 TREE_OVERFLOW (t
) = 1;
2317 TREE_CONSTANT_OVERFLOW (t
) = 1;
2319 else if (TREE_CONSTANT_OVERFLOW (arg1
))
2320 TREE_CONSTANT_OVERFLOW (t
) = 1;
2324 /* A subroutine of fold_convert_const handling conversions an INTEGER_CST
2325 to a fixed-point type. */
2328 fold_convert_const_fixed_from_int (tree type
, const_tree arg1
)
2330 FIXED_VALUE_TYPE value
;
2334 overflow_p
= fixed_convert_from_int (&value
, TYPE_MODE (type
),
2335 TREE_INT_CST (arg1
),
2336 TYPE_UNSIGNED (TREE_TYPE (arg1
)),
2337 TYPE_SATURATING (type
));
2338 t
= build_fixed (type
, value
);
2340 /* Propagate overflow flags. */
2341 if (overflow_p
| TREE_OVERFLOW (arg1
))
2343 TREE_OVERFLOW (t
) = 1;
2344 TREE_CONSTANT_OVERFLOW (t
) = 1;
2346 else if (TREE_CONSTANT_OVERFLOW (arg1
))
2347 TREE_CONSTANT_OVERFLOW (t
) = 1;
2351 /* A subroutine of fold_convert_const handling conversions a REAL_CST
2352 to a fixed-point type. */
2355 fold_convert_const_fixed_from_real (tree type
, const_tree arg1
)
2357 FIXED_VALUE_TYPE value
;
2361 overflow_p
= fixed_convert_from_real (&value
, TYPE_MODE (type
),
2362 &TREE_REAL_CST (arg1
),
2363 TYPE_SATURATING (type
));
2364 t
= build_fixed (type
, value
);
2366 /* Propagate overflow flags. */
2367 if (overflow_p
| TREE_OVERFLOW (arg1
))
2369 TREE_OVERFLOW (t
) = 1;
2370 TREE_CONSTANT_OVERFLOW (t
) = 1;
2372 else if (TREE_CONSTANT_OVERFLOW (arg1
))
2373 TREE_CONSTANT_OVERFLOW (t
) = 1;
2377 /* Attempt to fold type conversion operation CODE of expression ARG1 to
2378 type TYPE. If no simplification can be done return NULL_TREE. */
2381 fold_convert_const (enum tree_code code
, tree type
, tree arg1
)
2383 if (TREE_TYPE (arg1
) == type
)
2386 if (POINTER_TYPE_P (type
) || INTEGRAL_TYPE_P (type
))
2388 if (TREE_CODE (arg1
) == INTEGER_CST
)
2389 return fold_convert_const_int_from_int (type
, arg1
);
2390 else if (TREE_CODE (arg1
) == REAL_CST
)
2391 return fold_convert_const_int_from_real (code
, type
, arg1
);
2392 else if (TREE_CODE (arg1
) == FIXED_CST
)
2393 return fold_convert_const_int_from_fixed (type
, arg1
);
2395 else if (TREE_CODE (type
) == REAL_TYPE
)
2397 if (TREE_CODE (arg1
) == INTEGER_CST
)
2398 return build_real_from_int_cst (type
, arg1
);
2399 else if (TREE_CODE (arg1
) == REAL_CST
)
2400 return fold_convert_const_real_from_real (type
, arg1
);
2401 else if (TREE_CODE (arg1
) == FIXED_CST
)
2402 return fold_convert_const_real_from_fixed (type
, arg1
);
2404 else if (TREE_CODE (type
) == FIXED_POINT_TYPE
)
2406 if (TREE_CODE (arg1
) == FIXED_CST
)
2407 return fold_convert_const_fixed_from_fixed (type
, arg1
);
2408 else if (TREE_CODE (arg1
) == INTEGER_CST
)
2409 return fold_convert_const_fixed_from_int (type
, arg1
);
2410 else if (TREE_CODE (arg1
) == REAL_CST
)
2411 return fold_convert_const_fixed_from_real (type
, arg1
);
2416 /* Construct a vector of zero elements of vector type TYPE. */
2419 build_zero_vector (tree type
)
2424 elem
= fold_convert_const (NOP_EXPR
, TREE_TYPE (type
), integer_zero_node
);
2425 units
= TYPE_VECTOR_SUBPARTS (type
);
2428 for (i
= 0; i
< units
; i
++)
2429 list
= tree_cons (NULL_TREE
, elem
, list
);
2430 return build_vector (type
, list
);
2433 /* Returns true, if ARG is convertible to TYPE using a NOP_EXPR. */
2436 fold_convertible_p (const_tree type
, const_tree arg
)
2438 tree orig
= TREE_TYPE (arg
);
2443 if (TREE_CODE (arg
) == ERROR_MARK
2444 || TREE_CODE (type
) == ERROR_MARK
2445 || TREE_CODE (orig
) == ERROR_MARK
)
2448 if (TYPE_MAIN_VARIANT (type
) == TYPE_MAIN_VARIANT (orig
))
2451 switch (TREE_CODE (type
))
2453 case INTEGER_TYPE
: case ENUMERAL_TYPE
: case BOOLEAN_TYPE
:
2454 case POINTER_TYPE
: case REFERENCE_TYPE
:
2456 if (INTEGRAL_TYPE_P (orig
) || POINTER_TYPE_P (orig
)
2457 || TREE_CODE (orig
) == OFFSET_TYPE
)
2459 return (TREE_CODE (orig
) == VECTOR_TYPE
2460 && tree_int_cst_equal (TYPE_SIZE (type
), TYPE_SIZE (orig
)));
2463 return TREE_CODE (type
) == TREE_CODE (orig
);
2467 /* Convert expression ARG to type TYPE. Used by the middle-end for
2468 simple conversions in preference to calling the front-end's convert. */
2471 fold_convert (tree type
, tree arg
)
2473 tree orig
= TREE_TYPE (arg
);
2479 if (TREE_CODE (arg
) == ERROR_MARK
2480 || TREE_CODE (type
) == ERROR_MARK
2481 || TREE_CODE (orig
) == ERROR_MARK
)
2482 return error_mark_node
;
2484 if (TYPE_MAIN_VARIANT (type
) == TYPE_MAIN_VARIANT (orig
))
2485 return fold_build1 (NOP_EXPR
, type
, arg
);
2487 switch (TREE_CODE (type
))
2489 case INTEGER_TYPE
: case ENUMERAL_TYPE
: case BOOLEAN_TYPE
:
2490 case POINTER_TYPE
: case REFERENCE_TYPE
:
2492 if (TREE_CODE (arg
) == INTEGER_CST
)
2494 tem
= fold_convert_const (NOP_EXPR
, type
, arg
);
2495 if (tem
!= NULL_TREE
)
2498 if (INTEGRAL_TYPE_P (orig
) || POINTER_TYPE_P (orig
)
2499 || TREE_CODE (orig
) == OFFSET_TYPE
)
2500 return fold_build1 (NOP_EXPR
, type
, arg
);
2501 if (TREE_CODE (orig
) == COMPLEX_TYPE
)
2503 tem
= fold_build1 (REALPART_EXPR
, TREE_TYPE (orig
), arg
);
2504 return fold_convert (type
, tem
);
2506 gcc_assert (TREE_CODE (orig
) == VECTOR_TYPE
2507 && tree_int_cst_equal (TYPE_SIZE (type
), TYPE_SIZE (orig
)));
2508 return fold_build1 (NOP_EXPR
, type
, arg
);
2511 if (TREE_CODE (arg
) == INTEGER_CST
)
2513 tem
= fold_convert_const (FLOAT_EXPR
, type
, arg
);
2514 if (tem
!= NULL_TREE
)
2517 else if (TREE_CODE (arg
) == REAL_CST
)
2519 tem
= fold_convert_const (NOP_EXPR
, type
, arg
);
2520 if (tem
!= NULL_TREE
)
2523 else if (TREE_CODE (arg
) == FIXED_CST
)
2525 tem
= fold_convert_const (FIXED_CONVERT_EXPR
, type
, arg
);
2526 if (tem
!= NULL_TREE
)
2530 switch (TREE_CODE (orig
))
2533 case BOOLEAN_TYPE
: case ENUMERAL_TYPE
:
2534 case POINTER_TYPE
: case REFERENCE_TYPE
:
2535 return fold_build1 (FLOAT_EXPR
, type
, arg
);
2538 return fold_build1 (NOP_EXPR
, type
, arg
);
2540 case FIXED_POINT_TYPE
:
2541 return fold_build1 (FIXED_CONVERT_EXPR
, type
, arg
);
2544 tem
= fold_build1 (REALPART_EXPR
, TREE_TYPE (orig
), arg
);
2545 return fold_convert (type
, tem
);
2551 case FIXED_POINT_TYPE
:
2552 if (TREE_CODE (arg
) == FIXED_CST
|| TREE_CODE (arg
) == INTEGER_CST
2553 || TREE_CODE (arg
) == REAL_CST
)
2555 tem
= fold_convert_const (FIXED_CONVERT_EXPR
, type
, arg
);
2556 if (tem
!= NULL_TREE
)
2560 switch (TREE_CODE (orig
))
2562 case FIXED_POINT_TYPE
:
2567 return fold_build1 (FIXED_CONVERT_EXPR
, type
, arg
);
2570 tem
= fold_build1 (REALPART_EXPR
, TREE_TYPE (orig
), arg
);
2571 return fold_convert (type
, tem
);
2578 switch (TREE_CODE (orig
))
2581 case BOOLEAN_TYPE
: case ENUMERAL_TYPE
:
2582 case POINTER_TYPE
: case REFERENCE_TYPE
:
2584 case FIXED_POINT_TYPE
:
2585 return build2 (COMPLEX_EXPR
, type
,
2586 fold_convert (TREE_TYPE (type
), arg
),
2587 fold_convert (TREE_TYPE (type
), integer_zero_node
));
2592 if (TREE_CODE (arg
) == COMPLEX_EXPR
)
2594 rpart
= fold_convert (TREE_TYPE (type
), TREE_OPERAND (arg
, 0));
2595 ipart
= fold_convert (TREE_TYPE (type
), TREE_OPERAND (arg
, 1));
2596 return fold_build2 (COMPLEX_EXPR
, type
, rpart
, ipart
);
2599 arg
= save_expr (arg
);
2600 rpart
= fold_build1 (REALPART_EXPR
, TREE_TYPE (orig
), arg
);
2601 ipart
= fold_build1 (IMAGPART_EXPR
, TREE_TYPE (orig
), arg
);
2602 rpart
= fold_convert (TREE_TYPE (type
), rpart
);
2603 ipart
= fold_convert (TREE_TYPE (type
), ipart
);
2604 return fold_build2 (COMPLEX_EXPR
, type
, rpart
, ipart
);
2612 if (integer_zerop (arg
))
2613 return build_zero_vector (type
);
2614 gcc_assert (tree_int_cst_equal (TYPE_SIZE (type
), TYPE_SIZE (orig
)));
2615 gcc_assert (INTEGRAL_TYPE_P (orig
) || POINTER_TYPE_P (orig
)
2616 || TREE_CODE (orig
) == VECTOR_TYPE
);
2617 return fold_build1 (VIEW_CONVERT_EXPR
, type
, arg
);
2620 tem
= fold_ignored_result (arg
);
2621 if (TREE_CODE (tem
) == GIMPLE_MODIFY_STMT
)
2623 return fold_build1 (NOP_EXPR
, type
, tem
);
2630 /* Return false if expr can be assumed not to be an lvalue, true
2634 maybe_lvalue_p (const_tree x
)
2636 /* We only need to wrap lvalue tree codes. */
2637 switch (TREE_CODE (x
))
2648 case ALIGN_INDIRECT_REF
:
2649 case MISALIGNED_INDIRECT_REF
:
2651 case ARRAY_RANGE_REF
:
2657 case PREINCREMENT_EXPR
:
2658 case PREDECREMENT_EXPR
:
2660 case TRY_CATCH_EXPR
:
2661 case WITH_CLEANUP_EXPR
:
2664 case GIMPLE_MODIFY_STMT
:
2673 /* Assume the worst for front-end tree codes. */
2674 if ((int)TREE_CODE (x
) >= NUM_TREE_CODES
)
2682 /* Return an expr equal to X but certainly not valid as an lvalue. */
2687 /* While we are in GIMPLE, NON_LVALUE_EXPR doesn't mean anything to
2692 if (! maybe_lvalue_p (x
))
2694 return build1 (NON_LVALUE_EXPR
, TREE_TYPE (x
), x
);
2697 /* Nonzero means lvalues are limited to those valid in pedantic ANSI C.
2698 Zero means allow extended lvalues. */
2700 int pedantic_lvalues
;
2702 /* When pedantic, return an expr equal to X but certainly not valid as a
2703 pedantic lvalue. Otherwise, return X. */
2706 pedantic_non_lvalue (tree x
)
2708 if (pedantic_lvalues
)
2709 return non_lvalue (x
);
2714 /* Given a tree comparison code, return the code that is the logical inverse
2715 of the given code. It is not safe to do this for floating-point
2716 comparisons, except for NE_EXPR and EQ_EXPR, so we receive a machine mode
2717 as well: if reversing the comparison is unsafe, return ERROR_MARK. */
2720 invert_tree_comparison (enum tree_code code
, bool honor_nans
)
2722 if (honor_nans
&& flag_trapping_math
)
2732 return honor_nans
? UNLE_EXPR
: LE_EXPR
;
2734 return honor_nans
? UNLT_EXPR
: LT_EXPR
;
2736 return honor_nans
? UNGE_EXPR
: GE_EXPR
;
2738 return honor_nans
? UNGT_EXPR
: GT_EXPR
;
2752 return UNORDERED_EXPR
;
2753 case UNORDERED_EXPR
:
2754 return ORDERED_EXPR
;
2760 /* Similar, but return the comparison that results if the operands are
2761 swapped. This is safe for floating-point. */
2764 swap_tree_comparison (enum tree_code code
)
2771 case UNORDERED_EXPR
:
2797 /* Convert a comparison tree code from an enum tree_code representation
2798 into a compcode bit-based encoding. This function is the inverse of
2799 compcode_to_comparison. */
2801 static enum comparison_code
2802 comparison_to_compcode (enum tree_code code
)
2819 return COMPCODE_ORD
;
2820 case UNORDERED_EXPR
:
2821 return COMPCODE_UNORD
;
2823 return COMPCODE_UNLT
;
2825 return COMPCODE_UNEQ
;
2827 return COMPCODE_UNLE
;
2829 return COMPCODE_UNGT
;
2831 return COMPCODE_LTGT
;
2833 return COMPCODE_UNGE
;
2839 /* Convert a compcode bit-based encoding of a comparison operator back
2840 to GCC's enum tree_code representation. This function is the
2841 inverse of comparison_to_compcode. */
2843 static enum tree_code
2844 compcode_to_comparison (enum comparison_code code
)
2861 return ORDERED_EXPR
;
2862 case COMPCODE_UNORD
:
2863 return UNORDERED_EXPR
;
2881 /* Return a tree for the comparison which is the combination of
2882 doing the AND or OR (depending on CODE) of the two operations LCODE
2883 and RCODE on the identical operands LL_ARG and LR_ARG. Take into account
2884 the possibility of trapping if the mode has NaNs, and return NULL_TREE
2885 if this makes the transformation invalid. */
2888 combine_comparisons (enum tree_code code
, enum tree_code lcode
,
2889 enum tree_code rcode
, tree truth_type
,
2890 tree ll_arg
, tree lr_arg
)
2892 bool honor_nans
= HONOR_NANS (TYPE_MODE (TREE_TYPE (ll_arg
)));
2893 enum comparison_code lcompcode
= comparison_to_compcode (lcode
);
2894 enum comparison_code rcompcode
= comparison_to_compcode (rcode
);
2895 enum comparison_code compcode
;
2899 case TRUTH_AND_EXPR
: case TRUTH_ANDIF_EXPR
:
2900 compcode
= lcompcode
& rcompcode
;
2903 case TRUTH_OR_EXPR
: case TRUTH_ORIF_EXPR
:
2904 compcode
= lcompcode
| rcompcode
;
2913 /* Eliminate unordered comparisons, as well as LTGT and ORD
2914 which are not used unless the mode has NaNs. */
2915 compcode
&= ~COMPCODE_UNORD
;
2916 if (compcode
== COMPCODE_LTGT
)
2917 compcode
= COMPCODE_NE
;
2918 else if (compcode
== COMPCODE_ORD
)
2919 compcode
= COMPCODE_TRUE
;
2921 else if (flag_trapping_math
)
2923 /* Check that the original operation and the optimized ones will trap
2924 under the same condition. */
2925 bool ltrap
= (lcompcode
& COMPCODE_UNORD
) == 0
2926 && (lcompcode
!= COMPCODE_EQ
)
2927 && (lcompcode
!= COMPCODE_ORD
);
2928 bool rtrap
= (rcompcode
& COMPCODE_UNORD
) == 0
2929 && (rcompcode
!= COMPCODE_EQ
)
2930 && (rcompcode
!= COMPCODE_ORD
);
2931 bool trap
= (compcode
& COMPCODE_UNORD
) == 0
2932 && (compcode
!= COMPCODE_EQ
)
2933 && (compcode
!= COMPCODE_ORD
);
2935 /* In a short-circuited boolean expression the LHS might be
2936 such that the RHS, if evaluated, will never trap. For
2937 example, in ORD (x, y) && (x < y), we evaluate the RHS only
2938 if neither x nor y is NaN. (This is a mixed blessing: for
2939 example, the expression above will never trap, hence
2940 optimizing it to x < y would be invalid). */
2941 if ((code
== TRUTH_ORIF_EXPR
&& (lcompcode
& COMPCODE_UNORD
))
2942 || (code
== TRUTH_ANDIF_EXPR
&& !(lcompcode
& COMPCODE_UNORD
)))
2945 /* If the comparison was short-circuited, and only the RHS
2946 trapped, we may now generate a spurious trap. */
2948 && (code
== TRUTH_ANDIF_EXPR
|| code
== TRUTH_ORIF_EXPR
))
2951 /* If we changed the conditions that cause a trap, we lose. */
2952 if ((ltrap
|| rtrap
) != trap
)
2956 if (compcode
== COMPCODE_TRUE
)
2957 return constant_boolean_node (true, truth_type
);
2958 else if (compcode
== COMPCODE_FALSE
)
2959 return constant_boolean_node (false, truth_type
);
2961 return fold_build2 (compcode_to_comparison (compcode
),
2962 truth_type
, ll_arg
, lr_arg
);
2965 /* Return nonzero if CODE is a tree code that represents a truth value. */
2968 truth_value_p (enum tree_code code
)
2970 return (TREE_CODE_CLASS (code
) == tcc_comparison
2971 || code
== TRUTH_AND_EXPR
|| code
== TRUTH_ANDIF_EXPR
2972 || code
== TRUTH_OR_EXPR
|| code
== TRUTH_ORIF_EXPR
2973 || code
== TRUTH_XOR_EXPR
|| code
== TRUTH_NOT_EXPR
);
2976 /* Return nonzero if two operands (typically of the same tree node)
2977 are necessarily equal. If either argument has side-effects this
2978 function returns zero. FLAGS modifies behavior as follows:
2980 If OEP_ONLY_CONST is set, only return nonzero for constants.
2981 This function tests whether the operands are indistinguishable;
2982 it does not test whether they are equal using C's == operation.
2983 The distinction is important for IEEE floating point, because
2984 (1) -0.0 and 0.0 are distinguishable, but -0.0==0.0, and
2985 (2) two NaNs may be indistinguishable, but NaN!=NaN.
2987 If OEP_ONLY_CONST is unset, a VAR_DECL is considered equal to itself
2988 even though it may hold multiple values during a function.
2989 This is because a GCC tree node guarantees that nothing else is
2990 executed between the evaluation of its "operands" (which may often
2991 be evaluated in arbitrary order). Hence if the operands themselves
2992 don't side-effect, the VAR_DECLs, PARM_DECLs etc... must hold the
2993 same value in each operand/subexpression. Hence leaving OEP_ONLY_CONST
2994 unset means assuming isochronic (or instantaneous) tree equivalence.
2995 Unless comparing arbitrary expression trees, such as from different
2996 statements, this flag can usually be left unset.
2998 If OEP_PURE_SAME is set, then pure functions with identical arguments
2999 are considered the same. It is used when the caller has other ways
3000 to ensure that global memory is unchanged in between. */
3003 operand_equal_p (const_tree arg0
, const_tree arg1
, unsigned int flags
)
3005 /* If either is ERROR_MARK, they aren't equal. */
3006 if (TREE_CODE (arg0
) == ERROR_MARK
|| TREE_CODE (arg1
) == ERROR_MARK
)
3009 /* If both types don't have the same signedness, then we can't consider
3010 them equal. We must check this before the STRIP_NOPS calls
3011 because they may change the signedness of the arguments. */
3012 if (TYPE_UNSIGNED (TREE_TYPE (arg0
)) != TYPE_UNSIGNED (TREE_TYPE (arg1
)))
3015 /* If both types don't have the same precision, then it is not safe
3017 if (TYPE_PRECISION (TREE_TYPE (arg0
)) != TYPE_PRECISION (TREE_TYPE (arg1
)))
3023 /* In case both args are comparisons but with different comparison
3024 code, try to swap the comparison operands of one arg to produce
3025 a match and compare that variant. */
3026 if (TREE_CODE (arg0
) != TREE_CODE (arg1
)
3027 && COMPARISON_CLASS_P (arg0
)
3028 && COMPARISON_CLASS_P (arg1
))
3030 enum tree_code swap_code
= swap_tree_comparison (TREE_CODE (arg1
));
3032 if (TREE_CODE (arg0
) == swap_code
)
3033 return operand_equal_p (TREE_OPERAND (arg0
, 0),
3034 TREE_OPERAND (arg1
, 1), flags
)
3035 && operand_equal_p (TREE_OPERAND (arg0
, 1),
3036 TREE_OPERAND (arg1
, 0), flags
);
3039 if (TREE_CODE (arg0
) != TREE_CODE (arg1
)
3040 /* This is needed for conversions and for COMPONENT_REF.
3041 Might as well play it safe and always test this. */
3042 || TREE_CODE (TREE_TYPE (arg0
)) == ERROR_MARK
3043 || TREE_CODE (TREE_TYPE (arg1
)) == ERROR_MARK
3044 || TYPE_MODE (TREE_TYPE (arg0
)) != TYPE_MODE (TREE_TYPE (arg1
)))
3047 /* If ARG0 and ARG1 are the same SAVE_EXPR, they are necessarily equal.
3048 We don't care about side effects in that case because the SAVE_EXPR
3049 takes care of that for us. In all other cases, two expressions are
3050 equal if they have no side effects. If we have two identical
3051 expressions with side effects that should be treated the same due
3052 to the only side effects being identical SAVE_EXPR's, that will
3053 be detected in the recursive calls below. */
3054 if (arg0
== arg1
&& ! (flags
& OEP_ONLY_CONST
)
3055 && (TREE_CODE (arg0
) == SAVE_EXPR
3056 || (! TREE_SIDE_EFFECTS (arg0
) && ! TREE_SIDE_EFFECTS (arg1
))))
3059 /* Next handle constant cases, those for which we can return 1 even
3060 if ONLY_CONST is set. */
3061 if (TREE_CONSTANT (arg0
) && TREE_CONSTANT (arg1
))
3062 switch (TREE_CODE (arg0
))
3065 return tree_int_cst_equal (arg0
, arg1
);
3068 return FIXED_VALUES_IDENTICAL (TREE_FIXED_CST (arg0
),
3069 TREE_FIXED_CST (arg1
));
3072 if (REAL_VALUES_IDENTICAL (TREE_REAL_CST (arg0
),
3073 TREE_REAL_CST (arg1
)))
3077 if (!HONOR_SIGNED_ZEROS (TYPE_MODE (TREE_TYPE (arg0
))))
3079 /* If we do not distinguish between signed and unsigned zero,
3080 consider them equal. */
3081 if (real_zerop (arg0
) && real_zerop (arg1
))
3090 v1
= TREE_VECTOR_CST_ELTS (arg0
);
3091 v2
= TREE_VECTOR_CST_ELTS (arg1
);
3094 if (!operand_equal_p (TREE_VALUE (v1
), TREE_VALUE (v2
),
3097 v1
= TREE_CHAIN (v1
);
3098 v2
= TREE_CHAIN (v2
);
3105 return (operand_equal_p (TREE_REALPART (arg0
), TREE_REALPART (arg1
),
3107 && operand_equal_p (TREE_IMAGPART (arg0
), TREE_IMAGPART (arg1
),
3111 return (TREE_STRING_LENGTH (arg0
) == TREE_STRING_LENGTH (arg1
)
3112 && ! memcmp (TREE_STRING_POINTER (arg0
),
3113 TREE_STRING_POINTER (arg1
),
3114 TREE_STRING_LENGTH (arg0
)));
3117 return operand_equal_p (TREE_OPERAND (arg0
, 0), TREE_OPERAND (arg1
, 0),
3123 if (flags
& OEP_ONLY_CONST
)
3126 /* Define macros to test an operand from arg0 and arg1 for equality and a
3127 variant that allows null and views null as being different from any
3128 non-null value. In the latter case, if either is null, the both
3129 must be; otherwise, do the normal comparison. */
3130 #define OP_SAME(N) operand_equal_p (TREE_OPERAND (arg0, N), \
3131 TREE_OPERAND (arg1, N), flags)
3133 #define OP_SAME_WITH_NULL(N) \
3134 ((!TREE_OPERAND (arg0, N) || !TREE_OPERAND (arg1, N)) \
3135 ? TREE_OPERAND (arg0, N) == TREE_OPERAND (arg1, N) : OP_SAME (N))
3137 switch (TREE_CODE_CLASS (TREE_CODE (arg0
)))
3140 /* Two conversions are equal only if signedness and modes match. */
3141 switch (TREE_CODE (arg0
))
3145 case FIX_TRUNC_EXPR
:
3146 if (TYPE_UNSIGNED (TREE_TYPE (arg0
))
3147 != TYPE_UNSIGNED (TREE_TYPE (arg1
)))
3157 case tcc_comparison
:
3159 if (OP_SAME (0) && OP_SAME (1))
3162 /* For commutative ops, allow the other order. */
3163 return (commutative_tree_code (TREE_CODE (arg0
))
3164 && operand_equal_p (TREE_OPERAND (arg0
, 0),
3165 TREE_OPERAND (arg1
, 1), flags
)
3166 && operand_equal_p (TREE_OPERAND (arg0
, 1),
3167 TREE_OPERAND (arg1
, 0), flags
));
3170 /* If either of the pointer (or reference) expressions we are
3171 dereferencing contain a side effect, these cannot be equal. */
3172 if (TREE_SIDE_EFFECTS (arg0
)
3173 || TREE_SIDE_EFFECTS (arg1
))
3176 switch (TREE_CODE (arg0
))
3179 case ALIGN_INDIRECT_REF
:
3180 case MISALIGNED_INDIRECT_REF
:
3186 case ARRAY_RANGE_REF
:
3187 /* Operands 2 and 3 may be null.
3188 Compare the array index by value if it is constant first as we
3189 may have different types but same value here. */
3191 && (tree_int_cst_equal (TREE_OPERAND (arg0
, 1),
3192 TREE_OPERAND (arg1
, 1))
3194 && OP_SAME_WITH_NULL (2)
3195 && OP_SAME_WITH_NULL (3));
3198 /* Handle operand 2 the same as for ARRAY_REF. Operand 0
3199 may be NULL when we're called to compare MEM_EXPRs. */
3200 return OP_SAME_WITH_NULL (0)
3202 && OP_SAME_WITH_NULL (2);
3205 return OP_SAME (0) && OP_SAME (1) && OP_SAME (2);
3211 case tcc_expression
:
3212 switch (TREE_CODE (arg0
))
3215 case TRUTH_NOT_EXPR
:
3218 case TRUTH_ANDIF_EXPR
:
3219 case TRUTH_ORIF_EXPR
:
3220 return OP_SAME (0) && OP_SAME (1);
3222 case TRUTH_AND_EXPR
:
3224 case TRUTH_XOR_EXPR
:
3225 if (OP_SAME (0) && OP_SAME (1))
3228 /* Otherwise take into account this is a commutative operation. */
3229 return (operand_equal_p (TREE_OPERAND (arg0
, 0),
3230 TREE_OPERAND (arg1
, 1), flags
)
3231 && operand_equal_p (TREE_OPERAND (arg0
, 1),
3232 TREE_OPERAND (arg1
, 0), flags
));
3239 switch (TREE_CODE (arg0
))
3242 /* If the CALL_EXPRs call different functions, then they
3243 clearly can not be equal. */
3244 if (! operand_equal_p (CALL_EXPR_FN (arg0
), CALL_EXPR_FN (arg1
),
3249 unsigned int cef
= call_expr_flags (arg0
);
3250 if (flags
& OEP_PURE_SAME
)
3251 cef
&= ECF_CONST
| ECF_PURE
;
3258 /* Now see if all the arguments are the same. */
3260 const_call_expr_arg_iterator iter0
, iter1
;
3262 for (a0
= first_const_call_expr_arg (arg0
, &iter0
),
3263 a1
= first_const_call_expr_arg (arg1
, &iter1
);
3265 a0
= next_const_call_expr_arg (&iter0
),
3266 a1
= next_const_call_expr_arg (&iter1
))
3267 if (! operand_equal_p (a0
, a1
, flags
))
3270 /* If we get here and both argument lists are exhausted
3271 then the CALL_EXPRs are equal. */
3272 return ! (a0
|| a1
);
3278 case tcc_declaration
:
3279 /* Consider __builtin_sqrt equal to sqrt. */
3280 return (TREE_CODE (arg0
) == FUNCTION_DECL
3281 && DECL_BUILT_IN (arg0
) && DECL_BUILT_IN (arg1
)
3282 && DECL_BUILT_IN_CLASS (arg0
) == DECL_BUILT_IN_CLASS (arg1
)
3283 && DECL_FUNCTION_CODE (arg0
) == DECL_FUNCTION_CODE (arg1
));
3290 #undef OP_SAME_WITH_NULL
3293 /* Similar to operand_equal_p, but see if ARG0 might have been made by
3294 shorten_compare from ARG1 when ARG1 was being compared with OTHER.
3296 When in doubt, return 0. */
3299 operand_equal_for_comparison_p (tree arg0
, tree arg1
, tree other
)
3301 int unsignedp1
, unsignedpo
;
3302 tree primarg0
, primarg1
, primother
;
3303 unsigned int correct_width
;
3305 if (operand_equal_p (arg0
, arg1
, 0))
3308 if (! INTEGRAL_TYPE_P (TREE_TYPE (arg0
))
3309 || ! INTEGRAL_TYPE_P (TREE_TYPE (arg1
)))
3312 /* Discard any conversions that don't change the modes of ARG0 and ARG1
3313 and see if the inner values are the same. This removes any
3314 signedness comparison, which doesn't matter here. */
3315 primarg0
= arg0
, primarg1
= arg1
;
3316 STRIP_NOPS (primarg0
);
3317 STRIP_NOPS (primarg1
);
3318 if (operand_equal_p (primarg0
, primarg1
, 0))
3321 /* Duplicate what shorten_compare does to ARG1 and see if that gives the
3322 actual comparison operand, ARG0.
3324 First throw away any conversions to wider types
3325 already present in the operands. */
3327 primarg1
= get_narrower (arg1
, &unsignedp1
);
3328 primother
= get_narrower (other
, &unsignedpo
);
3330 correct_width
= TYPE_PRECISION (TREE_TYPE (arg1
));
3331 if (unsignedp1
== unsignedpo
3332 && TYPE_PRECISION (TREE_TYPE (primarg1
)) < correct_width
3333 && TYPE_PRECISION (TREE_TYPE (primother
)) < correct_width
)
3335 tree type
= TREE_TYPE (arg0
);
3337 /* Make sure shorter operand is extended the right way
3338 to match the longer operand. */
3339 primarg1
= fold_convert (signed_or_unsigned_type_for
3340 (unsignedp1
, TREE_TYPE (primarg1
)), primarg1
);
3342 if (operand_equal_p (arg0
, fold_convert (type
, primarg1
), 0))
3349 /* See if ARG is an expression that is either a comparison or is performing
3350 arithmetic on comparisons. The comparisons must only be comparing
3351 two different values, which will be stored in *CVAL1 and *CVAL2; if
3352 they are nonzero it means that some operands have already been found.
3353 No variables may be used anywhere else in the expression except in the
3354 comparisons. If SAVE_P is true it means we removed a SAVE_EXPR around
3355 the expression and save_expr needs to be called with CVAL1 and CVAL2.
3357 If this is true, return 1. Otherwise, return zero. */
3360 twoval_comparison_p (tree arg
, tree
*cval1
, tree
*cval2
, int *save_p
)
3362 enum tree_code code
= TREE_CODE (arg
);
3363 enum tree_code_class
class = TREE_CODE_CLASS (code
);
3365 /* We can handle some of the tcc_expression cases here. */
3366 if (class == tcc_expression
&& code
== TRUTH_NOT_EXPR
)
3368 else if (class == tcc_expression
3369 && (code
== TRUTH_ANDIF_EXPR
|| code
== TRUTH_ORIF_EXPR
3370 || code
== COMPOUND_EXPR
))
3373 else if (class == tcc_expression
&& code
== SAVE_EXPR
3374 && ! TREE_SIDE_EFFECTS (TREE_OPERAND (arg
, 0)))
3376 /* If we've already found a CVAL1 or CVAL2, this expression is
3377 two complex to handle. */
3378 if (*cval1
|| *cval2
)
3388 return twoval_comparison_p (TREE_OPERAND (arg
, 0), cval1
, cval2
, save_p
);
3391 return (twoval_comparison_p (TREE_OPERAND (arg
, 0), cval1
, cval2
, save_p
)
3392 && twoval_comparison_p (TREE_OPERAND (arg
, 1),
3393 cval1
, cval2
, save_p
));
3398 case tcc_expression
:
3399 if (code
== COND_EXPR
)
3400 return (twoval_comparison_p (TREE_OPERAND (arg
, 0),
3401 cval1
, cval2
, save_p
)
3402 && twoval_comparison_p (TREE_OPERAND (arg
, 1),
3403 cval1
, cval2
, save_p
)
3404 && twoval_comparison_p (TREE_OPERAND (arg
, 2),
3405 cval1
, cval2
, save_p
));
3408 case tcc_comparison
:
3409 /* First see if we can handle the first operand, then the second. For
3410 the second operand, we know *CVAL1 can't be zero. It must be that
3411 one side of the comparison is each of the values; test for the
3412 case where this isn't true by failing if the two operands
3415 if (operand_equal_p (TREE_OPERAND (arg
, 0),
3416 TREE_OPERAND (arg
, 1), 0))
3420 *cval1
= TREE_OPERAND (arg
, 0);
3421 else if (operand_equal_p (*cval1
, TREE_OPERAND (arg
, 0), 0))
3423 else if (*cval2
== 0)
3424 *cval2
= TREE_OPERAND (arg
, 0);
3425 else if (operand_equal_p (*cval2
, TREE_OPERAND (arg
, 0), 0))
3430 if (operand_equal_p (*cval1
, TREE_OPERAND (arg
, 1), 0))
3432 else if (*cval2
== 0)
3433 *cval2
= TREE_OPERAND (arg
, 1);
3434 else if (operand_equal_p (*cval2
, TREE_OPERAND (arg
, 1), 0))
3446 /* ARG is a tree that is known to contain just arithmetic operations and
3447 comparisons. Evaluate the operations in the tree substituting NEW0 for
3448 any occurrence of OLD0 as an operand of a comparison and likewise for
3452 eval_subst (tree arg
, tree old0
, tree new0
, tree old1
, tree new1
)
3454 tree type
= TREE_TYPE (arg
);
3455 enum tree_code code
= TREE_CODE (arg
);
3456 enum tree_code_class
class = TREE_CODE_CLASS (code
);
3458 /* We can handle some of the tcc_expression cases here. */
3459 if (class == tcc_expression
&& code
== TRUTH_NOT_EXPR
)
3461 else if (class == tcc_expression
3462 && (code
== TRUTH_ANDIF_EXPR
|| code
== TRUTH_ORIF_EXPR
))
3468 return fold_build1 (code
, type
,
3469 eval_subst (TREE_OPERAND (arg
, 0),
3470 old0
, new0
, old1
, new1
));
3473 return fold_build2 (code
, type
,
3474 eval_subst (TREE_OPERAND (arg
, 0),
3475 old0
, new0
, old1
, new1
),
3476 eval_subst (TREE_OPERAND (arg
, 1),
3477 old0
, new0
, old1
, new1
));
3479 case tcc_expression
:
3483 return eval_subst (TREE_OPERAND (arg
, 0), old0
, new0
, old1
, new1
);
3486 return eval_subst (TREE_OPERAND (arg
, 1), old0
, new0
, old1
, new1
);
3489 return fold_build3 (code
, type
,
3490 eval_subst (TREE_OPERAND (arg
, 0),
3491 old0
, new0
, old1
, new1
),
3492 eval_subst (TREE_OPERAND (arg
, 1),
3493 old0
, new0
, old1
, new1
),
3494 eval_subst (TREE_OPERAND (arg
, 2),
3495 old0
, new0
, old1
, new1
));
3499 /* Fall through - ??? */
3501 case tcc_comparison
:
3503 tree arg0
= TREE_OPERAND (arg
, 0);
3504 tree arg1
= TREE_OPERAND (arg
, 1);
3506 /* We need to check both for exact equality and tree equality. The
3507 former will be true if the operand has a side-effect. In that
3508 case, we know the operand occurred exactly once. */
3510 if (arg0
== old0
|| operand_equal_p (arg0
, old0
, 0))
3512 else if (arg0
== old1
|| operand_equal_p (arg0
, old1
, 0))
3515 if (arg1
== old0
|| operand_equal_p (arg1
, old0
, 0))
3517 else if (arg1
== old1
|| operand_equal_p (arg1
, old1
, 0))
3520 return fold_build2 (code
, type
, arg0
, arg1
);
3528 /* Return a tree for the case when the result of an expression is RESULT
3529 converted to TYPE and OMITTED was previously an operand of the expression
3530 but is now not needed (e.g., we folded OMITTED * 0).
3532 If OMITTED has side effects, we must evaluate it. Otherwise, just do
3533 the conversion of RESULT to TYPE. */
3536 omit_one_operand (tree type
, tree result
, tree omitted
)
3538 tree t
= fold_convert (type
, result
);
3540 /* If the resulting operand is an empty statement, just return the omitted
3541 statement casted to void. */
3542 if (IS_EMPTY_STMT (t
) && TREE_SIDE_EFFECTS (omitted
))
3543 return build1 (NOP_EXPR
, void_type_node
, fold_ignored_result (omitted
));
3545 if (TREE_SIDE_EFFECTS (omitted
))
3546 return build2 (COMPOUND_EXPR
, type
, fold_ignored_result (omitted
), t
);
3548 return non_lvalue (t
);
3551 /* Similar, but call pedantic_non_lvalue instead of non_lvalue. */
3554 pedantic_omit_one_operand (tree type
, tree result
, tree omitted
)
3556 tree t
= fold_convert (type
, result
);
3558 /* If the resulting operand is an empty statement, just return the omitted
3559 statement casted to void. */
3560 if (IS_EMPTY_STMT (t
) && TREE_SIDE_EFFECTS (omitted
))
3561 return build1 (NOP_EXPR
, void_type_node
, fold_ignored_result (omitted
));
3563 if (TREE_SIDE_EFFECTS (omitted
))
3564 return build2 (COMPOUND_EXPR
, type
, fold_ignored_result (omitted
), t
);
3566 return pedantic_non_lvalue (t
);
3569 /* Return a tree for the case when the result of an expression is RESULT
3570 converted to TYPE and OMITTED1 and OMITTED2 were previously operands
3571 of the expression but are now not needed.
3573 If OMITTED1 or OMITTED2 has side effects, they must be evaluated.
3574 If both OMITTED1 and OMITTED2 have side effects, OMITTED1 is
3575 evaluated before OMITTED2. Otherwise, if neither has side effects,
3576 just do the conversion of RESULT to TYPE. */
3579 omit_two_operands (tree type
, tree result
, tree omitted1
, tree omitted2
)
3581 tree t
= fold_convert (type
, result
);
3583 if (TREE_SIDE_EFFECTS (omitted2
))
3584 t
= build2 (COMPOUND_EXPR
, type
, omitted2
, t
);
3585 if (TREE_SIDE_EFFECTS (omitted1
))
3586 t
= build2 (COMPOUND_EXPR
, type
, omitted1
, t
);
3588 return TREE_CODE (t
) != COMPOUND_EXPR
? non_lvalue (t
) : t
;
3592 /* Return a simplified tree node for the truth-negation of ARG. This
3593 never alters ARG itself. We assume that ARG is an operation that
3594 returns a truth value (0 or 1).
3596 FIXME: one would think we would fold the result, but it causes
3597 problems with the dominator optimizer. */
3600 fold_truth_not_expr (tree arg
)
3602 tree type
= TREE_TYPE (arg
);
3603 enum tree_code code
= TREE_CODE (arg
);
3605 /* If this is a comparison, we can simply invert it, except for
3606 floating-point non-equality comparisons, in which case we just
3607 enclose a TRUTH_NOT_EXPR around what we have. */
3609 if (TREE_CODE_CLASS (code
) == tcc_comparison
)
3611 tree op_type
= TREE_TYPE (TREE_OPERAND (arg
, 0));
3612 if (FLOAT_TYPE_P (op_type
)
3613 && flag_trapping_math
3614 && code
!= ORDERED_EXPR
&& code
!= UNORDERED_EXPR
3615 && code
!= NE_EXPR
&& code
!= EQ_EXPR
)
3619 code
= invert_tree_comparison (code
,
3620 HONOR_NANS (TYPE_MODE (op_type
)));
3621 if (code
== ERROR_MARK
)
3624 return build2 (code
, type
,
3625 TREE_OPERAND (arg
, 0), TREE_OPERAND (arg
, 1));
3632 return constant_boolean_node (integer_zerop (arg
), type
);
3634 case TRUTH_AND_EXPR
:
3635 return build2 (TRUTH_OR_EXPR
, type
,
3636 invert_truthvalue (TREE_OPERAND (arg
, 0)),
3637 invert_truthvalue (TREE_OPERAND (arg
, 1)));
3640 return build2 (TRUTH_AND_EXPR
, type
,
3641 invert_truthvalue (TREE_OPERAND (arg
, 0)),
3642 invert_truthvalue (TREE_OPERAND (arg
, 1)));
3644 case TRUTH_XOR_EXPR
:
3645 /* Here we can invert either operand. We invert the first operand
3646 unless the second operand is a TRUTH_NOT_EXPR in which case our
3647 result is the XOR of the first operand with the inside of the
3648 negation of the second operand. */
3650 if (TREE_CODE (TREE_OPERAND (arg
, 1)) == TRUTH_NOT_EXPR
)
3651 return build2 (TRUTH_XOR_EXPR
, type
, TREE_OPERAND (arg
, 0),
3652 TREE_OPERAND (TREE_OPERAND (arg
, 1), 0));
3654 return build2 (TRUTH_XOR_EXPR
, type
,
3655 invert_truthvalue (TREE_OPERAND (arg
, 0)),
3656 TREE_OPERAND (arg
, 1));
3658 case TRUTH_ANDIF_EXPR
:
3659 return build2 (TRUTH_ORIF_EXPR
, type
,
3660 invert_truthvalue (TREE_OPERAND (arg
, 0)),
3661 invert_truthvalue (TREE_OPERAND (arg
, 1)));
3663 case TRUTH_ORIF_EXPR
:
3664 return build2 (TRUTH_ANDIF_EXPR
, type
,
3665 invert_truthvalue (TREE_OPERAND (arg
, 0)),
3666 invert_truthvalue (TREE_OPERAND (arg
, 1)));
3668 case TRUTH_NOT_EXPR
:
3669 return TREE_OPERAND (arg
, 0);
3673 tree arg1
= TREE_OPERAND (arg
, 1);
3674 tree arg2
= TREE_OPERAND (arg
, 2);
3675 /* A COND_EXPR may have a throw as one operand, which
3676 then has void type. Just leave void operands
3678 return build3 (COND_EXPR
, type
, TREE_OPERAND (arg
, 0),
3679 VOID_TYPE_P (TREE_TYPE (arg1
))
3680 ? arg1
: invert_truthvalue (arg1
),
3681 VOID_TYPE_P (TREE_TYPE (arg2
))
3682 ? arg2
: invert_truthvalue (arg2
));
3686 return build2 (COMPOUND_EXPR
, type
, TREE_OPERAND (arg
, 0),
3687 invert_truthvalue (TREE_OPERAND (arg
, 1)));
3689 case NON_LVALUE_EXPR
:
3690 return invert_truthvalue (TREE_OPERAND (arg
, 0));
3693 if (TREE_CODE (TREE_TYPE (arg
)) == BOOLEAN_TYPE
)
3694 return build1 (TRUTH_NOT_EXPR
, type
, arg
);
3698 return build1 (TREE_CODE (arg
), type
,
3699 invert_truthvalue (TREE_OPERAND (arg
, 0)));
3702 if (!integer_onep (TREE_OPERAND (arg
, 1)))
3704 return build2 (EQ_EXPR
, type
, arg
,
3705 build_int_cst (type
, 0));
3708 return build1 (TRUTH_NOT_EXPR
, type
, arg
);
3710 case CLEANUP_POINT_EXPR
:
3711 return build1 (CLEANUP_POINT_EXPR
, type
,
3712 invert_truthvalue (TREE_OPERAND (arg
, 0)));
3721 /* Return a simplified tree node for the truth-negation of ARG. This
3722 never alters ARG itself. We assume that ARG is an operation that
3723 returns a truth value (0 or 1).
3725 FIXME: one would think we would fold the result, but it causes
3726 problems with the dominator optimizer. */
3729 invert_truthvalue (tree arg
)
3733 if (TREE_CODE (arg
) == ERROR_MARK
)
3736 tem
= fold_truth_not_expr (arg
);
3738 tem
= build1 (TRUTH_NOT_EXPR
, TREE_TYPE (arg
), arg
);
3743 /* Given a bit-wise operation CODE applied to ARG0 and ARG1, see if both
3744 operands are another bit-wise operation with a common input. If so,
3745 distribute the bit operations to save an operation and possibly two if
3746 constants are involved. For example, convert
3747 (A | B) & (A | C) into A | (B & C)
3748 Further simplification will occur if B and C are constants.
3750 If this optimization cannot be done, 0 will be returned. */
3753 distribute_bit_expr (enum tree_code code
, tree type
, tree arg0
, tree arg1
)
3758 if (TREE_CODE (arg0
) != TREE_CODE (arg1
)
3759 || TREE_CODE (arg0
) == code
3760 || (TREE_CODE (arg0
) != BIT_AND_EXPR
3761 && TREE_CODE (arg0
) != BIT_IOR_EXPR
))
3764 if (operand_equal_p (TREE_OPERAND (arg0
, 0), TREE_OPERAND (arg1
, 0), 0))
3766 common
= TREE_OPERAND (arg0
, 0);
3767 left
= TREE_OPERAND (arg0
, 1);
3768 right
= TREE_OPERAND (arg1
, 1);
3770 else if (operand_equal_p (TREE_OPERAND (arg0
, 0), TREE_OPERAND (arg1
, 1), 0))
3772 common
= TREE_OPERAND (arg0
, 0);
3773 left
= TREE_OPERAND (arg0
, 1);
3774 right
= TREE_OPERAND (arg1
, 0);
3776 else if (operand_equal_p (TREE_OPERAND (arg0
, 1), TREE_OPERAND (arg1
, 0), 0))
3778 common
= TREE_OPERAND (arg0
, 1);
3779 left
= TREE_OPERAND (arg0
, 0);
3780 right
= TREE_OPERAND (arg1
, 1);
3782 else if (operand_equal_p (TREE_OPERAND (arg0
, 1), TREE_OPERAND (arg1
, 1), 0))
3784 common
= TREE_OPERAND (arg0
, 1);
3785 left
= TREE_OPERAND (arg0
, 0);
3786 right
= TREE_OPERAND (arg1
, 0);
3791 return fold_build2 (TREE_CODE (arg0
), type
, common
,
3792 fold_build2 (code
, type
, left
, right
));
3795 /* Knowing that ARG0 and ARG1 are both RDIV_EXPRs, simplify a binary operation
3796 with code CODE. This optimization is unsafe. */
3798 distribute_real_division (enum tree_code code
, tree type
, tree arg0
, tree arg1
)
3800 bool mul0
= TREE_CODE (arg0
) == MULT_EXPR
;
3801 bool mul1
= TREE_CODE (arg1
) == MULT_EXPR
;
3803 /* (A / C) +- (B / C) -> (A +- B) / C. */
3805 && operand_equal_p (TREE_OPERAND (arg0
, 1),
3806 TREE_OPERAND (arg1
, 1), 0))
3807 return fold_build2 (mul0
? MULT_EXPR
: RDIV_EXPR
, type
,
3808 fold_build2 (code
, type
,
3809 TREE_OPERAND (arg0
, 0),
3810 TREE_OPERAND (arg1
, 0)),
3811 TREE_OPERAND (arg0
, 1));
3813 /* (A / C1) +- (A / C2) -> A * (1 / C1 +- 1 / C2). */
3814 if (operand_equal_p (TREE_OPERAND (arg0
, 0),
3815 TREE_OPERAND (arg1
, 0), 0)
3816 && TREE_CODE (TREE_OPERAND (arg0
, 1)) == REAL_CST
3817 && TREE_CODE (TREE_OPERAND (arg1
, 1)) == REAL_CST
)
3819 REAL_VALUE_TYPE r0
, r1
;
3820 r0
= TREE_REAL_CST (TREE_OPERAND (arg0
, 1));
3821 r1
= TREE_REAL_CST (TREE_OPERAND (arg1
, 1));
3823 real_arithmetic (&r0
, RDIV_EXPR
, &dconst1
, &r0
);
3825 real_arithmetic (&r1
, RDIV_EXPR
, &dconst1
, &r1
);
3826 real_arithmetic (&r0
, code
, &r0
, &r1
);
3827 return fold_build2 (MULT_EXPR
, type
,
3828 TREE_OPERAND (arg0
, 0),
3829 build_real (type
, r0
));
3835 /* Return a BIT_FIELD_REF of type TYPE to refer to BITSIZE bits of INNER
3836 starting at BITPOS. The field is unsigned if UNSIGNEDP is nonzero. */
3839 make_bit_field_ref (tree inner
, tree type
, int bitsize
, int bitpos
,
3846 tree size
= TYPE_SIZE (TREE_TYPE (inner
));
3847 if ((INTEGRAL_TYPE_P (TREE_TYPE (inner
))
3848 || POINTER_TYPE_P (TREE_TYPE (inner
)))
3849 && host_integerp (size
, 0)
3850 && tree_low_cst (size
, 0) == bitsize
)
3851 return fold_convert (type
, inner
);
3854 result
= build3 (BIT_FIELD_REF
, type
, inner
,
3855 size_int (bitsize
), bitsize_int (bitpos
));
3857 BIT_FIELD_REF_UNSIGNED (result
) = unsignedp
;
3862 /* Optimize a bit-field compare.
3864 There are two cases: First is a compare against a constant and the
3865 second is a comparison of two items where the fields are at the same
3866 bit position relative to the start of a chunk (byte, halfword, word)
3867 large enough to contain it. In these cases we can avoid the shift
3868 implicit in bitfield extractions.
3870 For constants, we emit a compare of the shifted constant with the
3871 BIT_AND_EXPR of a mask and a byte, halfword, or word of the operand being
3872 compared. For two fields at the same position, we do the ANDs with the
3873 similar mask and compare the result of the ANDs.
3875 CODE is the comparison code, known to be either NE_EXPR or EQ_EXPR.
3876 COMPARE_TYPE is the type of the comparison, and LHS and RHS
3877 are the left and right operands of the comparison, respectively.
3879 If the optimization described above can be done, we return the resulting
3880 tree. Otherwise we return zero. */
3883 optimize_bit_field_compare (enum tree_code code
, tree compare_type
,
3886 HOST_WIDE_INT lbitpos
, lbitsize
, rbitpos
, rbitsize
, nbitpos
, nbitsize
;
3887 tree type
= TREE_TYPE (lhs
);
3888 tree signed_type
, unsigned_type
;
3889 int const_p
= TREE_CODE (rhs
) == INTEGER_CST
;
3890 enum machine_mode lmode
, rmode
, nmode
;
3891 int lunsignedp
, runsignedp
;
3892 int lvolatilep
= 0, rvolatilep
= 0;
3893 tree linner
, rinner
= NULL_TREE
;
3897 /* Get all the information about the extractions being done. If the bit size
3898 if the same as the size of the underlying object, we aren't doing an
3899 extraction at all and so can do nothing. We also don't want to
3900 do anything if the inner expression is a PLACEHOLDER_EXPR since we
3901 then will no longer be able to replace it. */
3902 linner
= get_inner_reference (lhs
, &lbitsize
, &lbitpos
, &offset
, &lmode
,
3903 &lunsignedp
, &lvolatilep
, false);
3904 if (linner
== lhs
|| lbitsize
== GET_MODE_BITSIZE (lmode
) || lbitsize
< 0
3905 || offset
!= 0 || TREE_CODE (linner
) == PLACEHOLDER_EXPR
)
3910 /* If this is not a constant, we can only do something if bit positions,
3911 sizes, and signedness are the same. */
3912 rinner
= get_inner_reference (rhs
, &rbitsize
, &rbitpos
, &offset
, &rmode
,
3913 &runsignedp
, &rvolatilep
, false);
3915 if (rinner
== rhs
|| lbitpos
!= rbitpos
|| lbitsize
!= rbitsize
3916 || lunsignedp
!= runsignedp
|| offset
!= 0
3917 || TREE_CODE (rinner
) == PLACEHOLDER_EXPR
)
3921 /* See if we can find a mode to refer to this field. We should be able to,
3922 but fail if we can't. */
3923 nmode
= get_best_mode (lbitsize
, lbitpos
,
3924 const_p
? TYPE_ALIGN (TREE_TYPE (linner
))
3925 : MIN (TYPE_ALIGN (TREE_TYPE (linner
)),
3926 TYPE_ALIGN (TREE_TYPE (rinner
))),
3927 word_mode
, lvolatilep
|| rvolatilep
);
3928 if (nmode
== VOIDmode
)
3931 /* Set signed and unsigned types of the precision of this mode for the
3933 signed_type
= lang_hooks
.types
.type_for_mode (nmode
, 0);
3934 unsigned_type
= lang_hooks
.types
.type_for_mode (nmode
, 1);
3936 /* Compute the bit position and size for the new reference and our offset
3937 within it. If the new reference is the same size as the original, we
3938 won't optimize anything, so return zero. */
3939 nbitsize
= GET_MODE_BITSIZE (nmode
);
3940 nbitpos
= lbitpos
& ~ (nbitsize
- 1);
3942 if (nbitsize
== lbitsize
)
3945 if (BYTES_BIG_ENDIAN
)
3946 lbitpos
= nbitsize
- lbitsize
- lbitpos
;
3948 /* Make the mask to be used against the extracted field. */
3949 mask
= build_int_cst_type (unsigned_type
, -1);
3950 mask
= const_binop (LSHIFT_EXPR
, mask
, size_int (nbitsize
- lbitsize
), 0);
3951 mask
= const_binop (RSHIFT_EXPR
, mask
,
3952 size_int (nbitsize
- lbitsize
- lbitpos
), 0);
3955 /* If not comparing with constant, just rework the comparison
3957 return fold_build2 (code
, compare_type
,
3958 fold_build2 (BIT_AND_EXPR
, unsigned_type
,
3959 make_bit_field_ref (linner
,
3964 fold_build2 (BIT_AND_EXPR
, unsigned_type
,
3965 make_bit_field_ref (rinner
,
3971 /* Otherwise, we are handling the constant case. See if the constant is too
3972 big for the field. Warn and return a tree of for 0 (false) if so. We do
3973 this not only for its own sake, but to avoid having to test for this
3974 error case below. If we didn't, we might generate wrong code.
3976 For unsigned fields, the constant shifted right by the field length should
3977 be all zero. For signed fields, the high-order bits should agree with
3982 if (! integer_zerop (const_binop (RSHIFT_EXPR
,
3983 fold_convert (unsigned_type
, rhs
),
3984 size_int (lbitsize
), 0)))
3986 warning (0, "comparison is always %d due to width of bit-field",
3988 return constant_boolean_node (code
== NE_EXPR
, compare_type
);
3993 tree tem
= const_binop (RSHIFT_EXPR
, fold_convert (signed_type
, rhs
),
3994 size_int (lbitsize
- 1), 0);
3995 if (! integer_zerop (tem
) && ! integer_all_onesp (tem
))
3997 warning (0, "comparison is always %d due to width of bit-field",
3999 return constant_boolean_node (code
== NE_EXPR
, compare_type
);
4003 /* Single-bit compares should always be against zero. */
4004 if (lbitsize
== 1 && ! integer_zerop (rhs
))
4006 code
= code
== EQ_EXPR
? NE_EXPR
: EQ_EXPR
;
4007 rhs
= build_int_cst (type
, 0);
4010 /* Make a new bitfield reference, shift the constant over the
4011 appropriate number of bits and mask it with the computed mask
4012 (in case this was a signed field). If we changed it, make a new one. */
4013 lhs
= make_bit_field_ref (linner
, unsigned_type
, nbitsize
, nbitpos
, 1);
4016 TREE_SIDE_EFFECTS (lhs
) = 1;
4017 TREE_THIS_VOLATILE (lhs
) = 1;
4020 rhs
= const_binop (BIT_AND_EXPR
,
4021 const_binop (LSHIFT_EXPR
,
4022 fold_convert (unsigned_type
, rhs
),
4023 size_int (lbitpos
), 0),
4026 return build2 (code
, compare_type
,
4027 build2 (BIT_AND_EXPR
, unsigned_type
, lhs
, mask
),
4031 /* Subroutine for fold_truthop: decode a field reference.
4033 If EXP is a comparison reference, we return the innermost reference.
4035 *PBITSIZE is set to the number of bits in the reference, *PBITPOS is
4036 set to the starting bit number.
4038 If the innermost field can be completely contained in a mode-sized
4039 unit, *PMODE is set to that mode. Otherwise, it is set to VOIDmode.
4041 *PVOLATILEP is set to 1 if the any expression encountered is volatile;
4042 otherwise it is not changed.
4044 *PUNSIGNEDP is set to the signedness of the field.
4046 *PMASK is set to the mask used. This is either contained in a
4047 BIT_AND_EXPR or derived from the width of the field.
4049 *PAND_MASK is set to the mask found in a BIT_AND_EXPR, if any.
4051 Return 0 if this is not a component reference or is one that we can't
4052 do anything with. */
4055 decode_field_reference (tree exp
, HOST_WIDE_INT
*pbitsize
,
4056 HOST_WIDE_INT
*pbitpos
, enum machine_mode
*pmode
,
4057 int *punsignedp
, int *pvolatilep
,
4058 tree
*pmask
, tree
*pand_mask
)
4060 tree outer_type
= 0;
4062 tree mask
, inner
, offset
;
4064 unsigned int precision
;
4066 /* All the optimizations using this function assume integer fields.
4067 There are problems with FP fields since the type_for_size call
4068 below can fail for, e.g., XFmode. */
4069 if (! INTEGRAL_TYPE_P (TREE_TYPE (exp
)))
4072 /* We are interested in the bare arrangement of bits, so strip everything
4073 that doesn't affect the machine mode. However, record the type of the
4074 outermost expression if it may matter below. */
4075 if (TREE_CODE (exp
) == NOP_EXPR
4076 || TREE_CODE (exp
) == CONVERT_EXPR
4077 || TREE_CODE (exp
) == NON_LVALUE_EXPR
)
4078 outer_type
= TREE_TYPE (exp
);
4081 if (TREE_CODE (exp
) == BIT_AND_EXPR
)
4083 and_mask
= TREE_OPERAND (exp
, 1);
4084 exp
= TREE_OPERAND (exp
, 0);
4085 STRIP_NOPS (exp
); STRIP_NOPS (and_mask
);
4086 if (TREE_CODE (and_mask
) != INTEGER_CST
)
4090 inner
= get_inner_reference (exp
, pbitsize
, pbitpos
, &offset
, pmode
,
4091 punsignedp
, pvolatilep
, false);
4092 if ((inner
== exp
&& and_mask
== 0)
4093 || *pbitsize
< 0 || offset
!= 0
4094 || TREE_CODE (inner
) == PLACEHOLDER_EXPR
)
4097 /* If the number of bits in the reference is the same as the bitsize of
4098 the outer type, then the outer type gives the signedness. Otherwise
4099 (in case of a small bitfield) the signedness is unchanged. */
4100 if (outer_type
&& *pbitsize
== TYPE_PRECISION (outer_type
))
4101 *punsignedp
= TYPE_UNSIGNED (outer_type
);
4103 /* Compute the mask to access the bitfield. */
4104 unsigned_type
= lang_hooks
.types
.type_for_size (*pbitsize
, 1);
4105 precision
= TYPE_PRECISION (unsigned_type
);
4107 mask
= build_int_cst_type (unsigned_type
, -1);
4109 mask
= const_binop (LSHIFT_EXPR
, mask
, size_int (precision
- *pbitsize
), 0);
4110 mask
= const_binop (RSHIFT_EXPR
, mask
, size_int (precision
- *pbitsize
), 0);
4112 /* Merge it with the mask we found in the BIT_AND_EXPR, if any. */
4114 mask
= fold_build2 (BIT_AND_EXPR
, unsigned_type
,
4115 fold_convert (unsigned_type
, and_mask
), mask
);
4118 *pand_mask
= and_mask
;
4122 /* Return nonzero if MASK represents a mask of SIZE ones in the low-order
4126 all_ones_mask_p (const_tree mask
, int size
)
4128 tree type
= TREE_TYPE (mask
);
4129 unsigned int precision
= TYPE_PRECISION (type
);
4132 tmask
= build_int_cst_type (signed_type_for (type
), -1);
4135 tree_int_cst_equal (mask
,
4136 const_binop (RSHIFT_EXPR
,
4137 const_binop (LSHIFT_EXPR
, tmask
,
4138 size_int (precision
- size
),
4140 size_int (precision
- size
), 0));
4143 /* Subroutine for fold: determine if VAL is the INTEGER_CONST that
4144 represents the sign bit of EXP's type. If EXP represents a sign
4145 or zero extension, also test VAL against the unextended type.
4146 The return value is the (sub)expression whose sign bit is VAL,
4147 or NULL_TREE otherwise. */
4150 sign_bit_p (tree exp
, const_tree val
)
4152 unsigned HOST_WIDE_INT mask_lo
, lo
;
4153 HOST_WIDE_INT mask_hi
, hi
;
4157 /* Tree EXP must have an integral type. */
4158 t
= TREE_TYPE (exp
);
4159 if (! INTEGRAL_TYPE_P (t
))
4162 /* Tree VAL must be an integer constant. */
4163 if (TREE_CODE (val
) != INTEGER_CST
4164 || TREE_OVERFLOW (val
))
4167 width
= TYPE_PRECISION (t
);
4168 if (width
> HOST_BITS_PER_WIDE_INT
)
4170 hi
= (unsigned HOST_WIDE_INT
) 1 << (width
- HOST_BITS_PER_WIDE_INT
- 1);
4173 mask_hi
= ((unsigned HOST_WIDE_INT
) -1
4174 >> (2 * HOST_BITS_PER_WIDE_INT
- width
));
4180 lo
= (unsigned HOST_WIDE_INT
) 1 << (width
- 1);
4183 mask_lo
= ((unsigned HOST_WIDE_INT
) -1
4184 >> (HOST_BITS_PER_WIDE_INT
- width
));
4187 /* We mask off those bits beyond TREE_TYPE (exp) so that we can
4188 treat VAL as if it were unsigned. */
4189 if ((TREE_INT_CST_HIGH (val
) & mask_hi
) == hi
4190 && (TREE_INT_CST_LOW (val
) & mask_lo
) == lo
)
4193 /* Handle extension from a narrower type. */
4194 if (TREE_CODE (exp
) == NOP_EXPR
4195 && TYPE_PRECISION (TREE_TYPE (TREE_OPERAND (exp
, 0))) < width
)
4196 return sign_bit_p (TREE_OPERAND (exp
, 0), val
);
4201 /* Subroutine for fold_truthop: determine if an operand is simple enough
4202 to be evaluated unconditionally. */
4205 simple_operand_p (const_tree exp
)
4207 /* Strip any conversions that don't change the machine mode. */
4210 return (CONSTANT_CLASS_P (exp
)
4211 || TREE_CODE (exp
) == SSA_NAME
4213 && ! TREE_ADDRESSABLE (exp
)
4214 && ! TREE_THIS_VOLATILE (exp
)
4215 && ! DECL_NONLOCAL (exp
)
4216 /* Don't regard global variables as simple. They may be
4217 allocated in ways unknown to the compiler (shared memory,
4218 #pragma weak, etc). */
4219 && ! TREE_PUBLIC (exp
)
4220 && ! DECL_EXTERNAL (exp
)
4221 /* Loading a static variable is unduly expensive, but global
4222 registers aren't expensive. */
4223 && (! TREE_STATIC (exp
) || DECL_REGISTER (exp
))));
4226 /* The following functions are subroutines to fold_range_test and allow it to
4227 try to change a logical combination of comparisons into a range test.
4230 X == 2 || X == 3 || X == 4 || X == 5
4234 (unsigned) (X - 2) <= 3
4236 We describe each set of comparisons as being either inside or outside
4237 a range, using a variable named like IN_P, and then describe the
4238 range with a lower and upper bound. If one of the bounds is omitted,
4239 it represents either the highest or lowest value of the type.
4241 In the comments below, we represent a range by two numbers in brackets
4242 preceded by a "+" to designate being inside that range, or a "-" to
4243 designate being outside that range, so the condition can be inverted by
4244 flipping the prefix. An omitted bound is represented by a "-". For
4245 example, "- [-, 10]" means being outside the range starting at the lowest
4246 possible value and ending at 10, in other words, being greater than 10.
4247 The range "+ [-, -]" is always true and hence the range "- [-, -]" is
4250 We set up things so that the missing bounds are handled in a consistent
4251 manner so neither a missing bound nor "true" and "false" need to be
4252 handled using a special case. */
4254 /* Return the result of applying CODE to ARG0 and ARG1, but handle the case
4255 of ARG0 and/or ARG1 being omitted, meaning an unlimited range. UPPER0_P
4256 and UPPER1_P are nonzero if the respective argument is an upper bound
4257 and zero for a lower. TYPE, if nonzero, is the type of the result; it
4258 must be specified for a comparison. ARG1 will be converted to ARG0's
4259 type if both are specified. */
4262 range_binop (enum tree_code code
, tree type
, tree arg0
, int upper0_p
,
4263 tree arg1
, int upper1_p
)
4269 /* If neither arg represents infinity, do the normal operation.
4270 Else, if not a comparison, return infinity. Else handle the special
4271 comparison rules. Note that most of the cases below won't occur, but
4272 are handled for consistency. */
4274 if (arg0
!= 0 && arg1
!= 0)
4276 tem
= fold_build2 (code
, type
!= 0 ? type
: TREE_TYPE (arg0
),
4277 arg0
, fold_convert (TREE_TYPE (arg0
), arg1
));
4279 return TREE_CODE (tem
) == INTEGER_CST
? tem
: 0;
4282 if (TREE_CODE_CLASS (code
) != tcc_comparison
)
4285 /* Set SGN[01] to -1 if ARG[01] is a lower bound, 1 for upper, and 0
4286 for neither. In real maths, we cannot assume open ended ranges are
4287 the same. But, this is computer arithmetic, where numbers are finite.
4288 We can therefore make the transformation of any unbounded range with
4289 the value Z, Z being greater than any representable number. This permits
4290 us to treat unbounded ranges as equal. */
4291 sgn0
= arg0
!= 0 ? 0 : (upper0_p
? 1 : -1);
4292 sgn1
= arg1
!= 0 ? 0 : (upper1_p
? 1 : -1);
4296 result
= sgn0
== sgn1
;
4299 result
= sgn0
!= sgn1
;
4302 result
= sgn0
< sgn1
;
4305 result
= sgn0
<= sgn1
;
4308 result
= sgn0
> sgn1
;
4311 result
= sgn0
>= sgn1
;
4317 return constant_boolean_node (result
, type
);
4320 /* Given EXP, a logical expression, set the range it is testing into
4321 variables denoted by PIN_P, PLOW, and PHIGH. Return the expression
4322 actually being tested. *PLOW and *PHIGH will be made of the same
4323 type as the returned expression. If EXP is not a comparison, we
4324 will most likely not be returning a useful value and range. Set
4325 *STRICT_OVERFLOW_P to true if the return value is only valid
4326 because signed overflow is undefined; otherwise, do not change
4327 *STRICT_OVERFLOW_P. */
4330 make_range (tree exp
, int *pin_p
, tree
*plow
, tree
*phigh
,
4331 bool *strict_overflow_p
)
4333 enum tree_code code
;
4334 tree arg0
= NULL_TREE
, arg1
= NULL_TREE
;
4335 tree exp_type
= NULL_TREE
, arg0_type
= NULL_TREE
;
4337 tree low
, high
, n_low
, n_high
;
4339 /* Start with simply saying "EXP != 0" and then look at the code of EXP
4340 and see if we can refine the range. Some of the cases below may not
4341 happen, but it doesn't seem worth worrying about this. We "continue"
4342 the outer loop when we've changed something; otherwise we "break"
4343 the switch, which will "break" the while. */
4346 low
= high
= build_int_cst (TREE_TYPE (exp
), 0);
4350 code
= TREE_CODE (exp
);
4351 exp_type
= TREE_TYPE (exp
);
4353 if (IS_EXPR_CODE_CLASS (TREE_CODE_CLASS (code
)))
4355 if (TREE_OPERAND_LENGTH (exp
) > 0)
4356 arg0
= TREE_OPERAND (exp
, 0);
4357 if (TREE_CODE_CLASS (code
) == tcc_comparison
4358 || TREE_CODE_CLASS (code
) == tcc_unary
4359 || TREE_CODE_CLASS (code
) == tcc_binary
)
4360 arg0_type
= TREE_TYPE (arg0
);
4361 if (TREE_CODE_CLASS (code
) == tcc_binary
4362 || TREE_CODE_CLASS (code
) == tcc_comparison
4363 || (TREE_CODE_CLASS (code
) == tcc_expression
4364 && TREE_OPERAND_LENGTH (exp
) > 1))
4365 arg1
= TREE_OPERAND (exp
, 1);
4370 case TRUTH_NOT_EXPR
:
4371 in_p
= ! in_p
, exp
= arg0
;
4374 case EQ_EXPR
: case NE_EXPR
:
4375 case LT_EXPR
: case LE_EXPR
: case GE_EXPR
: case GT_EXPR
:
4376 /* We can only do something if the range is testing for zero
4377 and if the second operand is an integer constant. Note that
4378 saying something is "in" the range we make is done by
4379 complementing IN_P since it will set in the initial case of
4380 being not equal to zero; "out" is leaving it alone. */
4381 if (low
== 0 || high
== 0
4382 || ! integer_zerop (low
) || ! integer_zerop (high
)
4383 || TREE_CODE (arg1
) != INTEGER_CST
)
4388 case NE_EXPR
: /* - [c, c] */
4391 case EQ_EXPR
: /* + [c, c] */
4392 in_p
= ! in_p
, low
= high
= arg1
;
4394 case GT_EXPR
: /* - [-, c] */
4395 low
= 0, high
= arg1
;
4397 case GE_EXPR
: /* + [c, -] */
4398 in_p
= ! in_p
, low
= arg1
, high
= 0;
4400 case LT_EXPR
: /* - [c, -] */
4401 low
= arg1
, high
= 0;
4403 case LE_EXPR
: /* + [-, c] */
4404 in_p
= ! in_p
, low
= 0, high
= arg1
;
4410 /* If this is an unsigned comparison, we also know that EXP is
4411 greater than or equal to zero. We base the range tests we make
4412 on that fact, so we record it here so we can parse existing
4413 range tests. We test arg0_type since often the return type
4414 of, e.g. EQ_EXPR, is boolean. */
4415 if (TYPE_UNSIGNED (arg0_type
) && (low
== 0 || high
== 0))
4417 if (! merge_ranges (&n_in_p
, &n_low
, &n_high
,
4419 build_int_cst (arg0_type
, 0),
4423 in_p
= n_in_p
, low
= n_low
, high
= n_high
;
4425 /* If the high bound is missing, but we have a nonzero low
4426 bound, reverse the range so it goes from zero to the low bound
4428 if (high
== 0 && low
&& ! integer_zerop (low
))
4431 high
= range_binop (MINUS_EXPR
, NULL_TREE
, low
, 0,
4432 integer_one_node
, 0);
4433 low
= build_int_cst (arg0_type
, 0);
4441 /* (-x) IN [a,b] -> x in [-b, -a] */
4442 n_low
= range_binop (MINUS_EXPR
, exp_type
,
4443 build_int_cst (exp_type
, 0),
4445 n_high
= range_binop (MINUS_EXPR
, exp_type
,
4446 build_int_cst (exp_type
, 0),
4448 low
= n_low
, high
= n_high
;
4454 exp
= build2 (MINUS_EXPR
, exp_type
, negate_expr (arg0
),
4455 build_int_cst (exp_type
, 1));
4458 case PLUS_EXPR
: case MINUS_EXPR
:
4459 if (TREE_CODE (arg1
) != INTEGER_CST
)
4462 /* If flag_wrapv and ARG0_TYPE is signed, then we cannot
4463 move a constant to the other side. */
4464 if (!TYPE_UNSIGNED (arg0_type
)
4465 && !TYPE_OVERFLOW_UNDEFINED (arg0_type
))
4468 /* If EXP is signed, any overflow in the computation is undefined,
4469 so we don't worry about it so long as our computations on
4470 the bounds don't overflow. For unsigned, overflow is defined
4471 and this is exactly the right thing. */
4472 n_low
= range_binop (code
== MINUS_EXPR
? PLUS_EXPR
: MINUS_EXPR
,
4473 arg0_type
, low
, 0, arg1
, 0);
4474 n_high
= range_binop (code
== MINUS_EXPR
? PLUS_EXPR
: MINUS_EXPR
,
4475 arg0_type
, high
, 1, arg1
, 0);
4476 if ((n_low
!= 0 && TREE_OVERFLOW (n_low
))
4477 || (n_high
!= 0 && TREE_OVERFLOW (n_high
)))
4480 if (TYPE_OVERFLOW_UNDEFINED (arg0_type
))
4481 *strict_overflow_p
= true;
4483 /* Check for an unsigned range which has wrapped around the maximum
4484 value thus making n_high < n_low, and normalize it. */
4485 if (n_low
&& n_high
&& tree_int_cst_lt (n_high
, n_low
))
4487 low
= range_binop (PLUS_EXPR
, arg0_type
, n_high
, 0,
4488 integer_one_node
, 0);
4489 high
= range_binop (MINUS_EXPR
, arg0_type
, n_low
, 0,
4490 integer_one_node
, 0);
4492 /* If the range is of the form +/- [ x+1, x ], we won't
4493 be able to normalize it. But then, it represents the
4494 whole range or the empty set, so make it
4496 if (tree_int_cst_equal (n_low
, low
)
4497 && tree_int_cst_equal (n_high
, high
))
4503 low
= n_low
, high
= n_high
;
4508 case NOP_EXPR
: case NON_LVALUE_EXPR
: case CONVERT_EXPR
:
4509 if (TYPE_PRECISION (arg0_type
) > TYPE_PRECISION (exp_type
))
4512 if (! INTEGRAL_TYPE_P (arg0_type
)
4513 || (low
!= 0 && ! int_fits_type_p (low
, arg0_type
))
4514 || (high
!= 0 && ! int_fits_type_p (high
, arg0_type
)))
4517 n_low
= low
, n_high
= high
;
4520 n_low
= fold_convert (arg0_type
, n_low
);
4523 n_high
= fold_convert (arg0_type
, n_high
);
4526 /* If we're converting arg0 from an unsigned type, to exp,
4527 a signed type, we will be doing the comparison as unsigned.
4528 The tests above have already verified that LOW and HIGH
4531 So we have to ensure that we will handle large unsigned
4532 values the same way that the current signed bounds treat
4535 if (!TYPE_UNSIGNED (exp_type
) && TYPE_UNSIGNED (arg0_type
))
4539 /* For fixed-point modes, we need to pass the saturating flag
4540 as the 2nd parameter. */
4541 if (ALL_FIXED_POINT_MODE_P (TYPE_MODE (arg0_type
)))
4542 equiv_type
= lang_hooks
.types
.type_for_mode
4543 (TYPE_MODE (arg0_type
),
4544 TYPE_SATURATING (arg0_type
));
4546 equiv_type
= lang_hooks
.types
.type_for_mode
4547 (TYPE_MODE (arg0_type
), 1);
4549 /* A range without an upper bound is, naturally, unbounded.
4550 Since convert would have cropped a very large value, use
4551 the max value for the destination type. */
4553 = TYPE_MAX_VALUE (equiv_type
) ? TYPE_MAX_VALUE (equiv_type
)
4554 : TYPE_MAX_VALUE (arg0_type
);
4556 if (TYPE_PRECISION (exp_type
) == TYPE_PRECISION (arg0_type
))
4557 high_positive
= fold_build2 (RSHIFT_EXPR
, arg0_type
,
4558 fold_convert (arg0_type
,
4560 build_int_cst (arg0_type
, 1));
4562 /* If the low bound is specified, "and" the range with the
4563 range for which the original unsigned value will be
4567 if (! merge_ranges (&n_in_p
, &n_low
, &n_high
,
4568 1, n_low
, n_high
, 1,
4569 fold_convert (arg0_type
,
4574 in_p
= (n_in_p
== in_p
);
4578 /* Otherwise, "or" the range with the range of the input
4579 that will be interpreted as negative. */
4580 if (! merge_ranges (&n_in_p
, &n_low
, &n_high
,
4581 0, n_low
, n_high
, 1,
4582 fold_convert (arg0_type
,
4587 in_p
= (in_p
!= n_in_p
);
4592 low
= n_low
, high
= n_high
;
4602 /* If EXP is a constant, we can evaluate whether this is true or false. */
4603 if (TREE_CODE (exp
) == INTEGER_CST
)
4605 in_p
= in_p
== (integer_onep (range_binop (GE_EXPR
, integer_type_node
,
4607 && integer_onep (range_binop (LE_EXPR
, integer_type_node
,
4613 *pin_p
= in_p
, *plow
= low
, *phigh
= high
;
4617 /* Given a range, LOW, HIGH, and IN_P, an expression, EXP, and a result
4618 type, TYPE, return an expression to test if EXP is in (or out of, depending
4619 on IN_P) the range. Return 0 if the test couldn't be created. */
4622 build_range_check (tree type
, tree exp
, int in_p
, tree low
, tree high
)
4624 tree etype
= TREE_TYPE (exp
);
4627 #ifdef HAVE_canonicalize_funcptr_for_compare
4628 /* Disable this optimization for function pointer expressions
4629 on targets that require function pointer canonicalization. */
4630 if (HAVE_canonicalize_funcptr_for_compare
4631 && TREE_CODE (etype
) == POINTER_TYPE
4632 && TREE_CODE (TREE_TYPE (etype
)) == FUNCTION_TYPE
)
4638 value
= build_range_check (type
, exp
, 1, low
, high
);
4640 return invert_truthvalue (value
);
4645 if (low
== 0 && high
== 0)
4646 return build_int_cst (type
, 1);
4649 return fold_build2 (LE_EXPR
, type
, exp
,
4650 fold_convert (etype
, high
));
4653 return fold_build2 (GE_EXPR
, type
, exp
,
4654 fold_convert (etype
, low
));
4656 if (operand_equal_p (low
, high
, 0))
4657 return fold_build2 (EQ_EXPR
, type
, exp
,
4658 fold_convert (etype
, low
));
4660 if (integer_zerop (low
))
4662 if (! TYPE_UNSIGNED (etype
))
4664 etype
= unsigned_type_for (etype
);
4665 high
= fold_convert (etype
, high
);
4666 exp
= fold_convert (etype
, exp
);
4668 return build_range_check (type
, exp
, 1, 0, high
);
4671 /* Optimize (c>=1) && (c<=127) into (signed char)c > 0. */
4672 if (integer_onep (low
) && TREE_CODE (high
) == INTEGER_CST
)
4674 unsigned HOST_WIDE_INT lo
;
4678 prec
= TYPE_PRECISION (etype
);
4679 if (prec
<= HOST_BITS_PER_WIDE_INT
)
4682 lo
= ((unsigned HOST_WIDE_INT
) 1 << (prec
- 1)) - 1;
4686 hi
= ((HOST_WIDE_INT
) 1 << (prec
- HOST_BITS_PER_WIDE_INT
- 1)) - 1;
4687 lo
= (unsigned HOST_WIDE_INT
) -1;
4690 if (TREE_INT_CST_HIGH (high
) == hi
&& TREE_INT_CST_LOW (high
) == lo
)
4692 if (TYPE_UNSIGNED (etype
))
4694 etype
= signed_type_for (etype
);
4695 exp
= fold_convert (etype
, exp
);
4697 return fold_build2 (GT_EXPR
, type
, exp
,
4698 build_int_cst (etype
, 0));
4702 /* Optimize (c>=low) && (c<=high) into (c-low>=0) && (c-low<=high-low).
4703 This requires wrap-around arithmetics for the type of the expression. */
4704 switch (TREE_CODE (etype
))
4707 /* There is no requirement that LOW be within the range of ETYPE
4708 if the latter is a subtype. It must, however, be within the base
4709 type of ETYPE. So be sure we do the subtraction in that type. */
4710 if (TREE_TYPE (etype
))
4711 etype
= TREE_TYPE (etype
);
4716 etype
= lang_hooks
.types
.type_for_size (TYPE_PRECISION (etype
),
4717 TYPE_UNSIGNED (etype
));
4724 /* If we don't have wrap-around arithmetics upfront, try to force it. */
4725 if (TREE_CODE (etype
) == INTEGER_TYPE
4726 && !TYPE_OVERFLOW_WRAPS (etype
))
4728 tree utype
, minv
, maxv
;
4730 /* Check if (unsigned) INT_MAX + 1 == (unsigned) INT_MIN
4731 for the type in question, as we rely on this here. */
4732 utype
= unsigned_type_for (etype
);
4733 maxv
= fold_convert (utype
, TYPE_MAX_VALUE (etype
));
4734 maxv
= range_binop (PLUS_EXPR
, NULL_TREE
, maxv
, 1,
4735 integer_one_node
, 1);
4736 minv
= fold_convert (utype
, TYPE_MIN_VALUE (etype
));
4738 if (integer_zerop (range_binop (NE_EXPR
, integer_type_node
,
4745 high
= fold_convert (etype
, high
);
4746 low
= fold_convert (etype
, low
);
4747 exp
= fold_convert (etype
, exp
);
4749 value
= const_binop (MINUS_EXPR
, high
, low
, 0);
4752 if (POINTER_TYPE_P (etype
))
4754 if (value
!= 0 && !TREE_OVERFLOW (value
))
4756 low
= fold_convert (sizetype
, low
);
4757 low
= fold_build1 (NEGATE_EXPR
, sizetype
, low
);
4758 return build_range_check (type
,
4759 fold_build2 (POINTER_PLUS_EXPR
, etype
, exp
, low
),
4760 1, build_int_cst (etype
, 0), value
);
4765 if (value
!= 0 && !TREE_OVERFLOW (value
))
4766 return build_range_check (type
,
4767 fold_build2 (MINUS_EXPR
, etype
, exp
, low
),
4768 1, build_int_cst (etype
, 0), value
);
4773 /* Return the predecessor of VAL in its type, handling the infinite case. */
4776 range_predecessor (tree val
)
4778 tree type
= TREE_TYPE (val
);
4780 if (INTEGRAL_TYPE_P (type
)
4781 && operand_equal_p (val
, TYPE_MIN_VALUE (type
), 0))
4784 return range_binop (MINUS_EXPR
, NULL_TREE
, val
, 0, integer_one_node
, 0);
4787 /* Return the successor of VAL in its type, handling the infinite case. */
4790 range_successor (tree val
)
4792 tree type
= TREE_TYPE (val
);
4794 if (INTEGRAL_TYPE_P (type
)
4795 && operand_equal_p (val
, TYPE_MAX_VALUE (type
), 0))
4798 return range_binop (PLUS_EXPR
, NULL_TREE
, val
, 0, integer_one_node
, 0);
4801 /* Given two ranges, see if we can merge them into one. Return 1 if we
4802 can, 0 if we can't. Set the output range into the specified parameters. */
4805 merge_ranges (int *pin_p
, tree
*plow
, tree
*phigh
, int in0_p
, tree low0
,
4806 tree high0
, int in1_p
, tree low1
, tree high1
)
4814 int lowequal
= ((low0
== 0 && low1
== 0)
4815 || integer_onep (range_binop (EQ_EXPR
, integer_type_node
,
4816 low0
, 0, low1
, 0)));
4817 int highequal
= ((high0
== 0 && high1
== 0)
4818 || integer_onep (range_binop (EQ_EXPR
, integer_type_node
,
4819 high0
, 1, high1
, 1)));
4821 /* Make range 0 be the range that starts first, or ends last if they
4822 start at the same value. Swap them if it isn't. */
4823 if (integer_onep (range_binop (GT_EXPR
, integer_type_node
,
4826 && integer_onep (range_binop (GT_EXPR
, integer_type_node
,
4827 high1
, 1, high0
, 1))))
4829 temp
= in0_p
, in0_p
= in1_p
, in1_p
= temp
;
4830 tem
= low0
, low0
= low1
, low1
= tem
;
4831 tem
= high0
, high0
= high1
, high1
= tem
;
4834 /* Now flag two cases, whether the ranges are disjoint or whether the
4835 second range is totally subsumed in the first. Note that the tests
4836 below are simplified by the ones above. */
4837 no_overlap
= integer_onep (range_binop (LT_EXPR
, integer_type_node
,
4838 high0
, 1, low1
, 0));
4839 subset
= integer_onep (range_binop (LE_EXPR
, integer_type_node
,
4840 high1
, 1, high0
, 1));
4842 /* We now have four cases, depending on whether we are including or
4843 excluding the two ranges. */
4846 /* If they don't overlap, the result is false. If the second range
4847 is a subset it is the result. Otherwise, the range is from the start
4848 of the second to the end of the first. */
4850 in_p
= 0, low
= high
= 0;
4852 in_p
= 1, low
= low1
, high
= high1
;
4854 in_p
= 1, low
= low1
, high
= high0
;
4857 else if (in0_p
&& ! in1_p
)
4859 /* If they don't overlap, the result is the first range. If they are
4860 equal, the result is false. If the second range is a subset of the
4861 first, and the ranges begin at the same place, we go from just after
4862 the end of the second range to the end of the first. If the second
4863 range is not a subset of the first, or if it is a subset and both
4864 ranges end at the same place, the range starts at the start of the
4865 first range and ends just before the second range.
4866 Otherwise, we can't describe this as a single range. */
4868 in_p
= 1, low
= low0
, high
= high0
;
4869 else if (lowequal
&& highequal
)
4870 in_p
= 0, low
= high
= 0;
4871 else if (subset
&& lowequal
)
4873 low
= range_successor (high1
);
4878 /* We are in the weird situation where high0 > high1 but
4879 high1 has no successor. Punt. */
4883 else if (! subset
|| highequal
)
4886 high
= range_predecessor (low1
);
4890 /* low0 < low1 but low1 has no predecessor. Punt. */
4898 else if (! in0_p
&& in1_p
)
4900 /* If they don't overlap, the result is the second range. If the second
4901 is a subset of the first, the result is false. Otherwise,
4902 the range starts just after the first range and ends at the
4903 end of the second. */
4905 in_p
= 1, low
= low1
, high
= high1
;
4906 else if (subset
|| highequal
)
4907 in_p
= 0, low
= high
= 0;
4910 low
= range_successor (high0
);
4915 /* high1 > high0 but high0 has no successor. Punt. */
4923 /* The case where we are excluding both ranges. Here the complex case
4924 is if they don't overlap. In that case, the only time we have a
4925 range is if they are adjacent. If the second is a subset of the
4926 first, the result is the first. Otherwise, the range to exclude
4927 starts at the beginning of the first range and ends at the end of the
4931 if (integer_onep (range_binop (EQ_EXPR
, integer_type_node
,
4932 range_successor (high0
),
4934 in_p
= 0, low
= low0
, high
= high1
;
4937 /* Canonicalize - [min, x] into - [-, x]. */
4938 if (low0
&& TREE_CODE (low0
) == INTEGER_CST
)
4939 switch (TREE_CODE (TREE_TYPE (low0
)))
4942 if (TYPE_PRECISION (TREE_TYPE (low0
))
4943 != GET_MODE_BITSIZE (TYPE_MODE (TREE_TYPE (low0
))))
4947 if (tree_int_cst_equal (low0
,
4948 TYPE_MIN_VALUE (TREE_TYPE (low0
))))
4952 if (TYPE_UNSIGNED (TREE_TYPE (low0
))
4953 && integer_zerop (low0
))
4960 /* Canonicalize - [x, max] into - [x, -]. */
4961 if (high1
&& TREE_CODE (high1
) == INTEGER_CST
)
4962 switch (TREE_CODE (TREE_TYPE (high1
)))
4965 if (TYPE_PRECISION (TREE_TYPE (high1
))
4966 != GET_MODE_BITSIZE (TYPE_MODE (TREE_TYPE (high1
))))
4970 if (tree_int_cst_equal (high1
,
4971 TYPE_MAX_VALUE (TREE_TYPE (high1
))))
4975 if (TYPE_UNSIGNED (TREE_TYPE (high1
))
4976 && integer_zerop (range_binop (PLUS_EXPR
, NULL_TREE
,
4978 integer_one_node
, 1)))
4985 /* The ranges might be also adjacent between the maximum and
4986 minimum values of the given type. For
4987 - [{min,-}, x] and - [y, {max,-}] ranges where x + 1 < y
4988 return + [x + 1, y - 1]. */
4989 if (low0
== 0 && high1
== 0)
4991 low
= range_successor (high0
);
4992 high
= range_predecessor (low1
);
4993 if (low
== 0 || high
== 0)
5003 in_p
= 0, low
= low0
, high
= high0
;
5005 in_p
= 0, low
= low0
, high
= high1
;
5008 *pin_p
= in_p
, *plow
= low
, *phigh
= high
;
5013 /* Subroutine of fold, looking inside expressions of the form
5014 A op B ? A : C, where ARG0, ARG1 and ARG2 are the three operands
5015 of the COND_EXPR. This function is being used also to optimize
5016 A op B ? C : A, by reversing the comparison first.
5018 Return a folded expression whose code is not a COND_EXPR
5019 anymore, or NULL_TREE if no folding opportunity is found. */
5022 fold_cond_expr_with_comparison (tree type
, tree arg0
, tree arg1
, tree arg2
)
5024 enum tree_code comp_code
= TREE_CODE (arg0
);
5025 tree arg00
= TREE_OPERAND (arg0
, 0);
5026 tree arg01
= TREE_OPERAND (arg0
, 1);
5027 tree arg1_type
= TREE_TYPE (arg1
);
5033 /* If we have A op 0 ? A : -A, consider applying the following
5036 A == 0? A : -A same as -A
5037 A != 0? A : -A same as A
5038 A >= 0? A : -A same as abs (A)
5039 A > 0? A : -A same as abs (A)
5040 A <= 0? A : -A same as -abs (A)
5041 A < 0? A : -A same as -abs (A)
5043 None of these transformations work for modes with signed
5044 zeros. If A is +/-0, the first two transformations will
5045 change the sign of the result (from +0 to -0, or vice
5046 versa). The last four will fix the sign of the result,
5047 even though the original expressions could be positive or
5048 negative, depending on the sign of A.
5050 Note that all these transformations are correct if A is
5051 NaN, since the two alternatives (A and -A) are also NaNs. */
5052 if ((FLOAT_TYPE_P (TREE_TYPE (arg01
))
5053 ? real_zerop (arg01
)
5054 : integer_zerop (arg01
))
5055 && ((TREE_CODE (arg2
) == NEGATE_EXPR
5056 && operand_equal_p (TREE_OPERAND (arg2
, 0), arg1
, 0))
5057 /* In the case that A is of the form X-Y, '-A' (arg2) may
5058 have already been folded to Y-X, check for that. */
5059 || (TREE_CODE (arg1
) == MINUS_EXPR
5060 && TREE_CODE (arg2
) == MINUS_EXPR
5061 && operand_equal_p (TREE_OPERAND (arg1
, 0),
5062 TREE_OPERAND (arg2
, 1), 0)
5063 && operand_equal_p (TREE_OPERAND (arg1
, 1),
5064 TREE_OPERAND (arg2
, 0), 0))))
5069 tem
= fold_convert (arg1_type
, arg1
);
5070 return pedantic_non_lvalue (fold_convert (type
, negate_expr (tem
)));
5073 return pedantic_non_lvalue (fold_convert (type
, arg1
));
5076 if (flag_trapping_math
)
5081 if (TYPE_UNSIGNED (TREE_TYPE (arg1
)))
5082 arg1
= fold_convert (signed_type_for
5083 (TREE_TYPE (arg1
)), arg1
);
5084 tem
= fold_build1 (ABS_EXPR
, TREE_TYPE (arg1
), arg1
);
5085 return pedantic_non_lvalue (fold_convert (type
, tem
));
5088 if (flag_trapping_math
)
5092 if (TYPE_UNSIGNED (TREE_TYPE (arg1
)))
5093 arg1
= fold_convert (signed_type_for
5094 (TREE_TYPE (arg1
)), arg1
);
5095 tem
= fold_build1 (ABS_EXPR
, TREE_TYPE (arg1
), arg1
);
5096 return negate_expr (fold_convert (type
, tem
));
5098 gcc_assert (TREE_CODE_CLASS (comp_code
) == tcc_comparison
);
5102 /* A != 0 ? A : 0 is simply A, unless A is -0. Likewise
5103 A == 0 ? A : 0 is always 0 unless A is -0. Note that
5104 both transformations are correct when A is NaN: A != 0
5105 is then true, and A == 0 is false. */
5107 if (integer_zerop (arg01
) && integer_zerop (arg2
))
5109 if (comp_code
== NE_EXPR
)
5110 return pedantic_non_lvalue (fold_convert (type
, arg1
));
5111 else if (comp_code
== EQ_EXPR
)
5112 return build_int_cst (type
, 0);
5115 /* Try some transformations of A op B ? A : B.
5117 A == B? A : B same as B
5118 A != B? A : B same as A
5119 A >= B? A : B same as max (A, B)
5120 A > B? A : B same as max (B, A)
5121 A <= B? A : B same as min (A, B)
5122 A < B? A : B same as min (B, A)
5124 As above, these transformations don't work in the presence
5125 of signed zeros. For example, if A and B are zeros of
5126 opposite sign, the first two transformations will change
5127 the sign of the result. In the last four, the original
5128 expressions give different results for (A=+0, B=-0) and
5129 (A=-0, B=+0), but the transformed expressions do not.
5131 The first two transformations are correct if either A or B
5132 is a NaN. In the first transformation, the condition will
5133 be false, and B will indeed be chosen. In the case of the
5134 second transformation, the condition A != B will be true,
5135 and A will be chosen.
5137 The conversions to max() and min() are not correct if B is
5138 a number and A is not. The conditions in the original
5139 expressions will be false, so all four give B. The min()
5140 and max() versions would give a NaN instead. */
5141 if (operand_equal_for_comparison_p (arg01
, arg2
, arg00
)
5142 /* Avoid these transformations if the COND_EXPR may be used
5143 as an lvalue in the C++ front-end. PR c++/19199. */
5145 || (strcmp (lang_hooks
.name
, "GNU C++") != 0
5146 && strcmp (lang_hooks
.name
, "GNU Objective-C++") != 0)
5147 || ! maybe_lvalue_p (arg1
)
5148 || ! maybe_lvalue_p (arg2
)))
5150 tree comp_op0
= arg00
;
5151 tree comp_op1
= arg01
;
5152 tree comp_type
= TREE_TYPE (comp_op0
);
5154 /* Avoid adding NOP_EXPRs in case this is an lvalue. */
5155 if (TYPE_MAIN_VARIANT (comp_type
) == TYPE_MAIN_VARIANT (type
))
5165 return pedantic_non_lvalue (fold_convert (type
, arg2
));
5167 return pedantic_non_lvalue (fold_convert (type
, arg1
));
5172 /* In C++ a ?: expression can be an lvalue, so put the
5173 operand which will be used if they are equal first
5174 so that we can convert this back to the
5175 corresponding COND_EXPR. */
5176 if (!HONOR_NANS (TYPE_MODE (TREE_TYPE (arg1
))))
5178 comp_op0
= fold_convert (comp_type
, comp_op0
);
5179 comp_op1
= fold_convert (comp_type
, comp_op1
);
5180 tem
= (comp_code
== LE_EXPR
|| comp_code
== UNLE_EXPR
)
5181 ? fold_build2 (MIN_EXPR
, comp_type
, comp_op0
, comp_op1
)
5182 : fold_build2 (MIN_EXPR
, comp_type
, comp_op1
, comp_op0
);
5183 return pedantic_non_lvalue (fold_convert (type
, tem
));
5190 if (!HONOR_NANS (TYPE_MODE (TREE_TYPE (arg1
))))
5192 comp_op0
= fold_convert (comp_type
, comp_op0
);
5193 comp_op1
= fold_convert (comp_type
, comp_op1
);
5194 tem
= (comp_code
== GE_EXPR
|| comp_code
== UNGE_EXPR
)
5195 ? fold_build2 (MAX_EXPR
, comp_type
, comp_op0
, comp_op1
)
5196 : fold_build2 (MAX_EXPR
, comp_type
, comp_op1
, comp_op0
);
5197 return pedantic_non_lvalue (fold_convert (type
, tem
));
5201 if (!HONOR_NANS (TYPE_MODE (TREE_TYPE (arg1
))))
5202 return pedantic_non_lvalue (fold_convert (type
, arg2
));
5205 if (!HONOR_NANS (TYPE_MODE (TREE_TYPE (arg1
))))
5206 return pedantic_non_lvalue (fold_convert (type
, arg1
));
5209 gcc_assert (TREE_CODE_CLASS (comp_code
) == tcc_comparison
);
5214 /* If this is A op C1 ? A : C2 with C1 and C2 constant integers,
5215 we might still be able to simplify this. For example,
5216 if C1 is one less or one more than C2, this might have started
5217 out as a MIN or MAX and been transformed by this function.
5218 Only good for INTEGER_TYPEs, because we need TYPE_MAX_VALUE. */
5220 if (INTEGRAL_TYPE_P (type
)
5221 && TREE_CODE (arg01
) == INTEGER_CST
5222 && TREE_CODE (arg2
) == INTEGER_CST
)
5226 /* We can replace A with C1 in this case. */
5227 arg1
= fold_convert (type
, arg01
);
5228 return fold_build3 (COND_EXPR
, type
, arg0
, arg1
, arg2
);
5231 /* If C1 is C2 + 1, this is min(A, C2). */
5232 if (! operand_equal_p (arg2
, TYPE_MAX_VALUE (type
),
5234 && operand_equal_p (arg01
,
5235 const_binop (PLUS_EXPR
, arg2
,
5236 build_int_cst (type
, 1), 0),
5238 return pedantic_non_lvalue (fold_build2 (MIN_EXPR
,
5240 fold_convert (type
, arg1
),
5245 /* If C1 is C2 - 1, this is min(A, C2). */
5246 if (! operand_equal_p (arg2
, TYPE_MIN_VALUE (type
),
5248 && operand_equal_p (arg01
,
5249 const_binop (MINUS_EXPR
, arg2
,
5250 build_int_cst (type
, 1), 0),
5252 return pedantic_non_lvalue (fold_build2 (MIN_EXPR
,
5254 fold_convert (type
, arg1
),
5259 /* If C1 is C2 - 1, this is max(A, C2). */
5260 if (! operand_equal_p (arg2
, TYPE_MIN_VALUE (type
),
5262 && operand_equal_p (arg01
,
5263 const_binop (MINUS_EXPR
, arg2
,
5264 build_int_cst (type
, 1), 0),
5266 return pedantic_non_lvalue (fold_build2 (MAX_EXPR
,
5268 fold_convert (type
, arg1
),
5273 /* If C1 is C2 + 1, this is max(A, C2). */
5274 if (! operand_equal_p (arg2
, TYPE_MAX_VALUE (type
),
5276 && operand_equal_p (arg01
,
5277 const_binop (PLUS_EXPR
, arg2
,
5278 build_int_cst (type
, 1), 0),
5280 return pedantic_non_lvalue (fold_build2 (MAX_EXPR
,
5282 fold_convert (type
, arg1
),
5296 #ifndef LOGICAL_OP_NON_SHORT_CIRCUIT
5297 #define LOGICAL_OP_NON_SHORT_CIRCUIT (BRANCH_COST >= 2)
5300 /* EXP is some logical combination of boolean tests. See if we can
5301 merge it into some range test. Return the new tree if so. */
5304 fold_range_test (enum tree_code code
, tree type
, tree op0
, tree op1
)
5306 int or_op
= (code
== TRUTH_ORIF_EXPR
5307 || code
== TRUTH_OR_EXPR
);
5308 int in0_p
, in1_p
, in_p
;
5309 tree low0
, low1
, low
, high0
, high1
, high
;
5310 bool strict_overflow_p
= false;
5311 tree lhs
= make_range (op0
, &in0_p
, &low0
, &high0
, &strict_overflow_p
);
5312 tree rhs
= make_range (op1
, &in1_p
, &low1
, &high1
, &strict_overflow_p
);
5314 const char * const warnmsg
= G_("assuming signed overflow does not occur "
5315 "when simplifying range test");
5317 /* If this is an OR operation, invert both sides; we will invert
5318 again at the end. */
5320 in0_p
= ! in0_p
, in1_p
= ! in1_p
;
5322 /* If both expressions are the same, if we can merge the ranges, and we
5323 can build the range test, return it or it inverted. If one of the
5324 ranges is always true or always false, consider it to be the same
5325 expression as the other. */
5326 if ((lhs
== 0 || rhs
== 0 || operand_equal_p (lhs
, rhs
, 0))
5327 && merge_ranges (&in_p
, &low
, &high
, in0_p
, low0
, high0
,
5329 && 0 != (tem
= (build_range_check (type
,
5331 : rhs
!= 0 ? rhs
: integer_zero_node
,
5334 if (strict_overflow_p
)
5335 fold_overflow_warning (warnmsg
, WARN_STRICT_OVERFLOW_COMPARISON
);
5336 return or_op
? invert_truthvalue (tem
) : tem
;
5339 /* On machines where the branch cost is expensive, if this is a
5340 short-circuited branch and the underlying object on both sides
5341 is the same, make a non-short-circuit operation. */
5342 else if (LOGICAL_OP_NON_SHORT_CIRCUIT
5343 && lhs
!= 0 && rhs
!= 0
5344 && (code
== TRUTH_ANDIF_EXPR
5345 || code
== TRUTH_ORIF_EXPR
)
5346 && operand_equal_p (lhs
, rhs
, 0))
5348 /* If simple enough, just rewrite. Otherwise, make a SAVE_EXPR
5349 unless we are at top level or LHS contains a PLACEHOLDER_EXPR, in
5350 which cases we can't do this. */
5351 if (simple_operand_p (lhs
))
5352 return build2 (code
== TRUTH_ANDIF_EXPR
5353 ? TRUTH_AND_EXPR
: TRUTH_OR_EXPR
,
5356 else if (lang_hooks
.decls
.global_bindings_p () == 0
5357 && ! CONTAINS_PLACEHOLDER_P (lhs
))
5359 tree common
= save_expr (lhs
);
5361 if (0 != (lhs
= build_range_check (type
, common
,
5362 or_op
? ! in0_p
: in0_p
,
5364 && (0 != (rhs
= build_range_check (type
, common
,
5365 or_op
? ! in1_p
: in1_p
,
5368 if (strict_overflow_p
)
5369 fold_overflow_warning (warnmsg
,
5370 WARN_STRICT_OVERFLOW_COMPARISON
);
5371 return build2 (code
== TRUTH_ANDIF_EXPR
5372 ? TRUTH_AND_EXPR
: TRUTH_OR_EXPR
,
5381 /* Subroutine for fold_truthop: C is an INTEGER_CST interpreted as a P
5382 bit value. Arrange things so the extra bits will be set to zero if and
5383 only if C is signed-extended to its full width. If MASK is nonzero,
5384 it is an INTEGER_CST that should be AND'ed with the extra bits. */
5387 unextend (tree c
, int p
, int unsignedp
, tree mask
)
5389 tree type
= TREE_TYPE (c
);
5390 int modesize
= GET_MODE_BITSIZE (TYPE_MODE (type
));
5393 if (p
== modesize
|| unsignedp
)
5396 /* We work by getting just the sign bit into the low-order bit, then
5397 into the high-order bit, then sign-extend. We then XOR that value
5399 temp
= const_binop (RSHIFT_EXPR
, c
, size_int (p
- 1), 0);
5400 temp
= const_binop (BIT_AND_EXPR
, temp
, size_int (1), 0);
5402 /* We must use a signed type in order to get an arithmetic right shift.
5403 However, we must also avoid introducing accidental overflows, so that
5404 a subsequent call to integer_zerop will work. Hence we must
5405 do the type conversion here. At this point, the constant is either
5406 zero or one, and the conversion to a signed type can never overflow.
5407 We could get an overflow if this conversion is done anywhere else. */
5408 if (TYPE_UNSIGNED (type
))
5409 temp
= fold_convert (signed_type_for (type
), temp
);
5411 temp
= const_binop (LSHIFT_EXPR
, temp
, size_int (modesize
- 1), 0);
5412 temp
= const_binop (RSHIFT_EXPR
, temp
, size_int (modesize
- p
- 1), 0);
5414 temp
= const_binop (BIT_AND_EXPR
, temp
,
5415 fold_convert (TREE_TYPE (c
), mask
), 0);
5416 /* If necessary, convert the type back to match the type of C. */
5417 if (TYPE_UNSIGNED (type
))
5418 temp
= fold_convert (type
, temp
);
5420 return fold_convert (type
, const_binop (BIT_XOR_EXPR
, c
, temp
, 0));
5423 /* Find ways of folding logical expressions of LHS and RHS:
5424 Try to merge two comparisons to the same innermost item.
5425 Look for range tests like "ch >= '0' && ch <= '9'".
5426 Look for combinations of simple terms on machines with expensive branches
5427 and evaluate the RHS unconditionally.
5429 For example, if we have p->a == 2 && p->b == 4 and we can make an
5430 object large enough to span both A and B, we can do this with a comparison
5431 against the object ANDed with the a mask.
5433 If we have p->a == q->a && p->b == q->b, we may be able to use bit masking
5434 operations to do this with one comparison.
5436 We check for both normal comparisons and the BIT_AND_EXPRs made this by
5437 function and the one above.
5439 CODE is the logical operation being done. It can be TRUTH_ANDIF_EXPR,
5440 TRUTH_AND_EXPR, TRUTH_ORIF_EXPR, or TRUTH_OR_EXPR.
5442 TRUTH_TYPE is the type of the logical operand and LHS and RHS are its
5445 We return the simplified tree or 0 if no optimization is possible. */
5448 fold_truthop (enum tree_code code
, tree truth_type
, tree lhs
, tree rhs
)
5450 /* If this is the "or" of two comparisons, we can do something if
5451 the comparisons are NE_EXPR. If this is the "and", we can do something
5452 if the comparisons are EQ_EXPR. I.e.,
5453 (a->b == 2 && a->c == 4) can become (a->new == NEW).
5455 WANTED_CODE is this operation code. For single bit fields, we can
5456 convert EQ_EXPR to NE_EXPR so we need not reject the "wrong"
5457 comparison for one-bit fields. */
5459 enum tree_code wanted_code
;
5460 enum tree_code lcode
, rcode
;
5461 tree ll_arg
, lr_arg
, rl_arg
, rr_arg
;
5462 tree ll_inner
, lr_inner
, rl_inner
, rr_inner
;
5463 HOST_WIDE_INT ll_bitsize
, ll_bitpos
, lr_bitsize
, lr_bitpos
;
5464 HOST_WIDE_INT rl_bitsize
, rl_bitpos
, rr_bitsize
, rr_bitpos
;
5465 HOST_WIDE_INT xll_bitpos
, xlr_bitpos
, xrl_bitpos
, xrr_bitpos
;
5466 HOST_WIDE_INT lnbitsize
, lnbitpos
, rnbitsize
, rnbitpos
;
5467 int ll_unsignedp
, lr_unsignedp
, rl_unsignedp
, rr_unsignedp
;
5468 enum machine_mode ll_mode
, lr_mode
, rl_mode
, rr_mode
;
5469 enum machine_mode lnmode
, rnmode
;
5470 tree ll_mask
, lr_mask
, rl_mask
, rr_mask
;
5471 tree ll_and_mask
, lr_and_mask
, rl_and_mask
, rr_and_mask
;
5472 tree l_const
, r_const
;
5473 tree lntype
, rntype
, result
;
5474 int first_bit
, end_bit
;
5476 tree orig_lhs
= lhs
, orig_rhs
= rhs
;
5477 enum tree_code orig_code
= code
;
5479 /* Start by getting the comparison codes. Fail if anything is volatile.
5480 If one operand is a BIT_AND_EXPR with the constant one, treat it as if
5481 it were surrounded with a NE_EXPR. */
5483 if (TREE_SIDE_EFFECTS (lhs
) || TREE_SIDE_EFFECTS (rhs
))
5486 lcode
= TREE_CODE (lhs
);
5487 rcode
= TREE_CODE (rhs
);
5489 if (lcode
== BIT_AND_EXPR
&& integer_onep (TREE_OPERAND (lhs
, 1)))
5491 lhs
= build2 (NE_EXPR
, truth_type
, lhs
,
5492 build_int_cst (TREE_TYPE (lhs
), 0));
5496 if (rcode
== BIT_AND_EXPR
&& integer_onep (TREE_OPERAND (rhs
, 1)))
5498 rhs
= build2 (NE_EXPR
, truth_type
, rhs
,
5499 build_int_cst (TREE_TYPE (rhs
), 0));
5503 if (TREE_CODE_CLASS (lcode
) != tcc_comparison
5504 || TREE_CODE_CLASS (rcode
) != tcc_comparison
)
5507 ll_arg
= TREE_OPERAND (lhs
, 0);
5508 lr_arg
= TREE_OPERAND (lhs
, 1);
5509 rl_arg
= TREE_OPERAND (rhs
, 0);
5510 rr_arg
= TREE_OPERAND (rhs
, 1);
5512 /* Simplify (x<y) && (x==y) into (x<=y) and related optimizations. */
5513 if (simple_operand_p (ll_arg
)
5514 && simple_operand_p (lr_arg
))
5517 if (operand_equal_p (ll_arg
, rl_arg
, 0)
5518 && operand_equal_p (lr_arg
, rr_arg
, 0))
5520 result
= combine_comparisons (code
, lcode
, rcode
,
5521 truth_type
, ll_arg
, lr_arg
);
5525 else if (operand_equal_p (ll_arg
, rr_arg
, 0)
5526 && operand_equal_p (lr_arg
, rl_arg
, 0))
5528 result
= combine_comparisons (code
, lcode
,
5529 swap_tree_comparison (rcode
),
5530 truth_type
, ll_arg
, lr_arg
);
5536 code
= ((code
== TRUTH_AND_EXPR
|| code
== TRUTH_ANDIF_EXPR
)
5537 ? TRUTH_AND_EXPR
: TRUTH_OR_EXPR
);
5539 /* If the RHS can be evaluated unconditionally and its operands are
5540 simple, it wins to evaluate the RHS unconditionally on machines
5541 with expensive branches. In this case, this isn't a comparison
5542 that can be merged. Avoid doing this if the RHS is a floating-point
5543 comparison since those can trap. */
5545 if (BRANCH_COST
>= 2
5546 && ! FLOAT_TYPE_P (TREE_TYPE (rl_arg
))
5547 && simple_operand_p (rl_arg
)
5548 && simple_operand_p (rr_arg
))
5550 /* Convert (a != 0) || (b != 0) into (a | b) != 0. */
5551 if (code
== TRUTH_OR_EXPR
5552 && lcode
== NE_EXPR
&& integer_zerop (lr_arg
)
5553 && rcode
== NE_EXPR
&& integer_zerop (rr_arg
)
5554 && TREE_TYPE (ll_arg
) == TREE_TYPE (rl_arg
))
5555 return build2 (NE_EXPR
, truth_type
,
5556 build2 (BIT_IOR_EXPR
, TREE_TYPE (ll_arg
),
5558 build_int_cst (TREE_TYPE (ll_arg
), 0));
5560 /* Convert (a == 0) && (b == 0) into (a | b) == 0. */
5561 if (code
== TRUTH_AND_EXPR
5562 && lcode
== EQ_EXPR
&& integer_zerop (lr_arg
)
5563 && rcode
== EQ_EXPR
&& integer_zerop (rr_arg
)
5564 && TREE_TYPE (ll_arg
) == TREE_TYPE (rl_arg
))
5565 return build2 (EQ_EXPR
, truth_type
,
5566 build2 (BIT_IOR_EXPR
, TREE_TYPE (ll_arg
),
5568 build_int_cst (TREE_TYPE (ll_arg
), 0));
5570 if (LOGICAL_OP_NON_SHORT_CIRCUIT
)
5572 if (code
!= orig_code
|| lhs
!= orig_lhs
|| rhs
!= orig_rhs
)
5573 return build2 (code
, truth_type
, lhs
, rhs
);
5578 /* See if the comparisons can be merged. Then get all the parameters for
5581 if ((lcode
!= EQ_EXPR
&& lcode
!= NE_EXPR
)
5582 || (rcode
!= EQ_EXPR
&& rcode
!= NE_EXPR
))
5586 ll_inner
= decode_field_reference (ll_arg
,
5587 &ll_bitsize
, &ll_bitpos
, &ll_mode
,
5588 &ll_unsignedp
, &volatilep
, &ll_mask
,
5590 lr_inner
= decode_field_reference (lr_arg
,
5591 &lr_bitsize
, &lr_bitpos
, &lr_mode
,
5592 &lr_unsignedp
, &volatilep
, &lr_mask
,
5594 rl_inner
= decode_field_reference (rl_arg
,
5595 &rl_bitsize
, &rl_bitpos
, &rl_mode
,
5596 &rl_unsignedp
, &volatilep
, &rl_mask
,
5598 rr_inner
= decode_field_reference (rr_arg
,
5599 &rr_bitsize
, &rr_bitpos
, &rr_mode
,
5600 &rr_unsignedp
, &volatilep
, &rr_mask
,
5603 /* It must be true that the inner operation on the lhs of each
5604 comparison must be the same if we are to be able to do anything.
5605 Then see if we have constants. If not, the same must be true for
5607 if (volatilep
|| ll_inner
== 0 || rl_inner
== 0
5608 || ! operand_equal_p (ll_inner
, rl_inner
, 0))
5611 if (TREE_CODE (lr_arg
) == INTEGER_CST
5612 && TREE_CODE (rr_arg
) == INTEGER_CST
)
5613 l_const
= lr_arg
, r_const
= rr_arg
;
5614 else if (lr_inner
== 0 || rr_inner
== 0
5615 || ! operand_equal_p (lr_inner
, rr_inner
, 0))
5618 l_const
= r_const
= 0;
5620 /* If either comparison code is not correct for our logical operation,
5621 fail. However, we can convert a one-bit comparison against zero into
5622 the opposite comparison against that bit being set in the field. */
5624 wanted_code
= (code
== TRUTH_AND_EXPR
? EQ_EXPR
: NE_EXPR
);
5625 if (lcode
!= wanted_code
)
5627 if (l_const
&& integer_zerop (l_const
) && integer_pow2p (ll_mask
))
5629 /* Make the left operand unsigned, since we are only interested
5630 in the value of one bit. Otherwise we are doing the wrong
5639 /* This is analogous to the code for l_const above. */
5640 if (rcode
!= wanted_code
)
5642 if (r_const
&& integer_zerop (r_const
) && integer_pow2p (rl_mask
))
5651 /* See if we can find a mode that contains both fields being compared on
5652 the left. If we can't, fail. Otherwise, update all constants and masks
5653 to be relative to a field of that size. */
5654 first_bit
= MIN (ll_bitpos
, rl_bitpos
);
5655 end_bit
= MAX (ll_bitpos
+ ll_bitsize
, rl_bitpos
+ rl_bitsize
);
5656 lnmode
= get_best_mode (end_bit
- first_bit
, first_bit
,
5657 TYPE_ALIGN (TREE_TYPE (ll_inner
)), word_mode
,
5659 if (lnmode
== VOIDmode
)
5662 lnbitsize
= GET_MODE_BITSIZE (lnmode
);
5663 lnbitpos
= first_bit
& ~ (lnbitsize
- 1);
5664 lntype
= lang_hooks
.types
.type_for_size (lnbitsize
, 1);
5665 xll_bitpos
= ll_bitpos
- lnbitpos
, xrl_bitpos
= rl_bitpos
- lnbitpos
;
5667 if (BYTES_BIG_ENDIAN
)
5669 xll_bitpos
= lnbitsize
- xll_bitpos
- ll_bitsize
;
5670 xrl_bitpos
= lnbitsize
- xrl_bitpos
- rl_bitsize
;
5673 ll_mask
= const_binop (LSHIFT_EXPR
, fold_convert (lntype
, ll_mask
),
5674 size_int (xll_bitpos
), 0);
5675 rl_mask
= const_binop (LSHIFT_EXPR
, fold_convert (lntype
, rl_mask
),
5676 size_int (xrl_bitpos
), 0);
5680 l_const
= fold_convert (lntype
, l_const
);
5681 l_const
= unextend (l_const
, ll_bitsize
, ll_unsignedp
, ll_and_mask
);
5682 l_const
= const_binop (LSHIFT_EXPR
, l_const
, size_int (xll_bitpos
), 0);
5683 if (! integer_zerop (const_binop (BIT_AND_EXPR
, l_const
,
5684 fold_build1 (BIT_NOT_EXPR
,
5688 warning (0, "comparison is always %d", wanted_code
== NE_EXPR
);
5690 return constant_boolean_node (wanted_code
== NE_EXPR
, truth_type
);
5695 r_const
= fold_convert (lntype
, r_const
);
5696 r_const
= unextend (r_const
, rl_bitsize
, rl_unsignedp
, rl_and_mask
);
5697 r_const
= const_binop (LSHIFT_EXPR
, r_const
, size_int (xrl_bitpos
), 0);
5698 if (! integer_zerop (const_binop (BIT_AND_EXPR
, r_const
,
5699 fold_build1 (BIT_NOT_EXPR
,
5703 warning (0, "comparison is always %d", wanted_code
== NE_EXPR
);
5705 return constant_boolean_node (wanted_code
== NE_EXPR
, truth_type
);
5709 /* If the right sides are not constant, do the same for it. Also,
5710 disallow this optimization if a size or signedness mismatch occurs
5711 between the left and right sides. */
5714 if (ll_bitsize
!= lr_bitsize
|| rl_bitsize
!= rr_bitsize
5715 || ll_unsignedp
!= lr_unsignedp
|| rl_unsignedp
!= rr_unsignedp
5716 /* Make sure the two fields on the right
5717 correspond to the left without being swapped. */
5718 || ll_bitpos
- rl_bitpos
!= lr_bitpos
- rr_bitpos
)
5721 first_bit
= MIN (lr_bitpos
, rr_bitpos
);
5722 end_bit
= MAX (lr_bitpos
+ lr_bitsize
, rr_bitpos
+ rr_bitsize
);
5723 rnmode
= get_best_mode (end_bit
- first_bit
, first_bit
,
5724 TYPE_ALIGN (TREE_TYPE (lr_inner
)), word_mode
,
5726 if (rnmode
== VOIDmode
)
5729 rnbitsize
= GET_MODE_BITSIZE (rnmode
);
5730 rnbitpos
= first_bit
& ~ (rnbitsize
- 1);
5731 rntype
= lang_hooks
.types
.type_for_size (rnbitsize
, 1);
5732 xlr_bitpos
= lr_bitpos
- rnbitpos
, xrr_bitpos
= rr_bitpos
- rnbitpos
;
5734 if (BYTES_BIG_ENDIAN
)
5736 xlr_bitpos
= rnbitsize
- xlr_bitpos
- lr_bitsize
;
5737 xrr_bitpos
= rnbitsize
- xrr_bitpos
- rr_bitsize
;
5740 lr_mask
= const_binop (LSHIFT_EXPR
, fold_convert (rntype
, lr_mask
),
5741 size_int (xlr_bitpos
), 0);
5742 rr_mask
= const_binop (LSHIFT_EXPR
, fold_convert (rntype
, rr_mask
),
5743 size_int (xrr_bitpos
), 0);
5745 /* Make a mask that corresponds to both fields being compared.
5746 Do this for both items being compared. If the operands are the
5747 same size and the bits being compared are in the same position
5748 then we can do this by masking both and comparing the masked
5750 ll_mask
= const_binop (BIT_IOR_EXPR
, ll_mask
, rl_mask
, 0);
5751 lr_mask
= const_binop (BIT_IOR_EXPR
, lr_mask
, rr_mask
, 0);
5752 if (lnbitsize
== rnbitsize
&& xll_bitpos
== xlr_bitpos
)
5754 lhs
= make_bit_field_ref (ll_inner
, lntype
, lnbitsize
, lnbitpos
,
5755 ll_unsignedp
|| rl_unsignedp
);
5756 if (! all_ones_mask_p (ll_mask
, lnbitsize
))
5757 lhs
= build2 (BIT_AND_EXPR
, lntype
, lhs
, ll_mask
);
5759 rhs
= make_bit_field_ref (lr_inner
, rntype
, rnbitsize
, rnbitpos
,
5760 lr_unsignedp
|| rr_unsignedp
);
5761 if (! all_ones_mask_p (lr_mask
, rnbitsize
))
5762 rhs
= build2 (BIT_AND_EXPR
, rntype
, rhs
, lr_mask
);
5764 return build2 (wanted_code
, truth_type
, lhs
, rhs
);
5767 /* There is still another way we can do something: If both pairs of
5768 fields being compared are adjacent, we may be able to make a wider
5769 field containing them both.
5771 Note that we still must mask the lhs/rhs expressions. Furthermore,
5772 the mask must be shifted to account for the shift done by
5773 make_bit_field_ref. */
5774 if ((ll_bitsize
+ ll_bitpos
== rl_bitpos
5775 && lr_bitsize
+ lr_bitpos
== rr_bitpos
)
5776 || (ll_bitpos
== rl_bitpos
+ rl_bitsize
5777 && lr_bitpos
== rr_bitpos
+ rr_bitsize
))
5781 lhs
= make_bit_field_ref (ll_inner
, lntype
, ll_bitsize
+ rl_bitsize
,
5782 MIN (ll_bitpos
, rl_bitpos
), ll_unsignedp
);
5783 rhs
= make_bit_field_ref (lr_inner
, rntype
, lr_bitsize
+ rr_bitsize
,
5784 MIN (lr_bitpos
, rr_bitpos
), lr_unsignedp
);
5786 ll_mask
= const_binop (RSHIFT_EXPR
, ll_mask
,
5787 size_int (MIN (xll_bitpos
, xrl_bitpos
)), 0);
5788 lr_mask
= const_binop (RSHIFT_EXPR
, lr_mask
,
5789 size_int (MIN (xlr_bitpos
, xrr_bitpos
)), 0);
5791 /* Convert to the smaller type before masking out unwanted bits. */
5793 if (lntype
!= rntype
)
5795 if (lnbitsize
> rnbitsize
)
5797 lhs
= fold_convert (rntype
, lhs
);
5798 ll_mask
= fold_convert (rntype
, ll_mask
);
5801 else if (lnbitsize
< rnbitsize
)
5803 rhs
= fold_convert (lntype
, rhs
);
5804 lr_mask
= fold_convert (lntype
, lr_mask
);
5809 if (! all_ones_mask_p (ll_mask
, ll_bitsize
+ rl_bitsize
))
5810 lhs
= build2 (BIT_AND_EXPR
, type
, lhs
, ll_mask
);
5812 if (! all_ones_mask_p (lr_mask
, lr_bitsize
+ rr_bitsize
))
5813 rhs
= build2 (BIT_AND_EXPR
, type
, rhs
, lr_mask
);
5815 return build2 (wanted_code
, truth_type
, lhs
, rhs
);
5821 /* Handle the case of comparisons with constants. If there is something in
5822 common between the masks, those bits of the constants must be the same.
5823 If not, the condition is always false. Test for this to avoid generating
5824 incorrect code below. */
5825 result
= const_binop (BIT_AND_EXPR
, ll_mask
, rl_mask
, 0);
5826 if (! integer_zerop (result
)
5827 && simple_cst_equal (const_binop (BIT_AND_EXPR
, result
, l_const
, 0),
5828 const_binop (BIT_AND_EXPR
, result
, r_const
, 0)) != 1)
5830 if (wanted_code
== NE_EXPR
)
5832 warning (0, "%<or%> of unmatched not-equal tests is always 1");
5833 return constant_boolean_node (true, truth_type
);
5837 warning (0, "%<and%> of mutually exclusive equal-tests is always 0");
5838 return constant_boolean_node (false, truth_type
);
5842 /* Construct the expression we will return. First get the component
5843 reference we will make. Unless the mask is all ones the width of
5844 that field, perform the mask operation. Then compare with the
5846 result
= make_bit_field_ref (ll_inner
, lntype
, lnbitsize
, lnbitpos
,
5847 ll_unsignedp
|| rl_unsignedp
);
5849 ll_mask
= const_binop (BIT_IOR_EXPR
, ll_mask
, rl_mask
, 0);
5850 if (! all_ones_mask_p (ll_mask
, lnbitsize
))
5851 result
= build2 (BIT_AND_EXPR
, lntype
, result
, ll_mask
);
5853 return build2 (wanted_code
, truth_type
, result
,
5854 const_binop (BIT_IOR_EXPR
, l_const
, r_const
, 0));
5857 /* Optimize T, which is a comparison of a MIN_EXPR or MAX_EXPR with a
5861 optimize_minmax_comparison (enum tree_code code
, tree type
, tree op0
, tree op1
)
5864 enum tree_code op_code
;
5865 tree comp_const
= op1
;
5867 int consts_equal
, consts_lt
;
5870 STRIP_SIGN_NOPS (arg0
);
5872 op_code
= TREE_CODE (arg0
);
5873 minmax_const
= TREE_OPERAND (arg0
, 1);
5874 consts_equal
= tree_int_cst_equal (minmax_const
, comp_const
);
5875 consts_lt
= tree_int_cst_lt (minmax_const
, comp_const
);
5876 inner
= TREE_OPERAND (arg0
, 0);
5878 /* If something does not permit us to optimize, return the original tree. */
5879 if ((op_code
!= MIN_EXPR
&& op_code
!= MAX_EXPR
)
5880 || TREE_CODE (comp_const
) != INTEGER_CST
5881 || TREE_OVERFLOW (comp_const
)
5882 || TREE_CODE (minmax_const
) != INTEGER_CST
5883 || TREE_OVERFLOW (minmax_const
))
5886 /* Now handle all the various comparison codes. We only handle EQ_EXPR
5887 and GT_EXPR, doing the rest with recursive calls using logical
5891 case NE_EXPR
: case LT_EXPR
: case LE_EXPR
:
5893 tree tem
= optimize_minmax_comparison (invert_tree_comparison (code
, false),
5896 return invert_truthvalue (tem
);
5902 fold_build2 (TRUTH_ORIF_EXPR
, type
,
5903 optimize_minmax_comparison
5904 (EQ_EXPR
, type
, arg0
, comp_const
),
5905 optimize_minmax_comparison
5906 (GT_EXPR
, type
, arg0
, comp_const
));
5909 if (op_code
== MAX_EXPR
&& consts_equal
)
5910 /* MAX (X, 0) == 0 -> X <= 0 */
5911 return fold_build2 (LE_EXPR
, type
, inner
, comp_const
);
5913 else if (op_code
== MAX_EXPR
&& consts_lt
)
5914 /* MAX (X, 0) == 5 -> X == 5 */
5915 return fold_build2 (EQ_EXPR
, type
, inner
, comp_const
);
5917 else if (op_code
== MAX_EXPR
)
5918 /* MAX (X, 0) == -1 -> false */
5919 return omit_one_operand (type
, integer_zero_node
, inner
);
5921 else if (consts_equal
)
5922 /* MIN (X, 0) == 0 -> X >= 0 */
5923 return fold_build2 (GE_EXPR
, type
, inner
, comp_const
);
5926 /* MIN (X, 0) == 5 -> false */
5927 return omit_one_operand (type
, integer_zero_node
, inner
);
5930 /* MIN (X, 0) == -1 -> X == -1 */
5931 return fold_build2 (EQ_EXPR
, type
, inner
, comp_const
);
5934 if (op_code
== MAX_EXPR
&& (consts_equal
|| consts_lt
))
5935 /* MAX (X, 0) > 0 -> X > 0
5936 MAX (X, 0) > 5 -> X > 5 */
5937 return fold_build2 (GT_EXPR
, type
, inner
, comp_const
);
5939 else if (op_code
== MAX_EXPR
)
5940 /* MAX (X, 0) > -1 -> true */
5941 return omit_one_operand (type
, integer_one_node
, inner
);
5943 else if (op_code
== MIN_EXPR
&& (consts_equal
|| consts_lt
))
5944 /* MIN (X, 0) > 0 -> false
5945 MIN (X, 0) > 5 -> false */
5946 return omit_one_operand (type
, integer_zero_node
, inner
);
5949 /* MIN (X, 0) > -1 -> X > -1 */
5950 return fold_build2 (GT_EXPR
, type
, inner
, comp_const
);
5957 /* T is an integer expression that is being multiplied, divided, or taken a
5958 modulus (CODE says which and what kind of divide or modulus) by a
5959 constant C. See if we can eliminate that operation by folding it with
5960 other operations already in T. WIDE_TYPE, if non-null, is a type that
5961 should be used for the computation if wider than our type.
5963 For example, if we are dividing (X * 8) + (Y * 16) by 4, we can return
5964 (X * 2) + (Y * 4). We must, however, be assured that either the original
5965 expression would not overflow or that overflow is undefined for the type
5966 in the language in question.
5968 We also canonicalize (X + 7) * 4 into X * 4 + 28 in the hope that either
5969 the machine has a multiply-accumulate insn or that this is part of an
5970 addressing calculation.
5972 If we return a non-null expression, it is an equivalent form of the
5973 original computation, but need not be in the original type.
5975 We set *STRICT_OVERFLOW_P to true if the return values depends on
5976 signed overflow being undefined. Otherwise we do not change
5977 *STRICT_OVERFLOW_P. */
5980 extract_muldiv (tree t
, tree c
, enum tree_code code
, tree wide_type
,
5981 bool *strict_overflow_p
)
5983 /* To avoid exponential search depth, refuse to allow recursion past
5984 three levels. Beyond that (1) it's highly unlikely that we'll find
5985 something interesting and (2) we've probably processed it before
5986 when we built the inner expression. */
5995 ret
= extract_muldiv_1 (t
, c
, code
, wide_type
, strict_overflow_p
);
6002 extract_muldiv_1 (tree t
, tree c
, enum tree_code code
, tree wide_type
,
6003 bool *strict_overflow_p
)
6005 tree type
= TREE_TYPE (t
);
6006 enum tree_code tcode
= TREE_CODE (t
);
6007 tree ctype
= (wide_type
!= 0 && (GET_MODE_SIZE (TYPE_MODE (wide_type
))
6008 > GET_MODE_SIZE (TYPE_MODE (type
)))
6009 ? wide_type
: type
);
6011 int same_p
= tcode
== code
;
6012 tree op0
= NULL_TREE
, op1
= NULL_TREE
;
6013 bool sub_strict_overflow_p
;
6015 /* Don't deal with constants of zero here; they confuse the code below. */
6016 if (integer_zerop (c
))
6019 if (TREE_CODE_CLASS (tcode
) == tcc_unary
)
6020 op0
= TREE_OPERAND (t
, 0);
6022 if (TREE_CODE_CLASS (tcode
) == tcc_binary
)
6023 op0
= TREE_OPERAND (t
, 0), op1
= TREE_OPERAND (t
, 1);
6025 /* Note that we need not handle conditional operations here since fold
6026 already handles those cases. So just do arithmetic here. */
6030 /* For a constant, we can always simplify if we are a multiply
6031 or (for divide and modulus) if it is a multiple of our constant. */
6032 if (code
== MULT_EXPR
6033 || integer_zerop (const_binop (TRUNC_MOD_EXPR
, t
, c
, 0)))
6034 return const_binop (code
, fold_convert (ctype
, t
),
6035 fold_convert (ctype
, c
), 0);
6038 case CONVERT_EXPR
: case NON_LVALUE_EXPR
: case NOP_EXPR
:
6039 /* If op0 is an expression ... */
6040 if ((COMPARISON_CLASS_P (op0
)
6041 || UNARY_CLASS_P (op0
)
6042 || BINARY_CLASS_P (op0
)
6043 || VL_EXP_CLASS_P (op0
)
6044 || EXPRESSION_CLASS_P (op0
))
6045 /* ... and is unsigned, and its type is smaller than ctype,
6046 then we cannot pass through as widening. */
6047 && ((TYPE_UNSIGNED (TREE_TYPE (op0
))
6048 && ! (TREE_CODE (TREE_TYPE (op0
)) == INTEGER_TYPE
6049 && TYPE_IS_SIZETYPE (TREE_TYPE (op0
)))
6050 && (GET_MODE_SIZE (TYPE_MODE (ctype
))
6051 > GET_MODE_SIZE (TYPE_MODE (TREE_TYPE (op0
)))))
6052 /* ... or this is a truncation (t is narrower than op0),
6053 then we cannot pass through this narrowing. */
6054 || (GET_MODE_SIZE (TYPE_MODE (type
))
6055 < GET_MODE_SIZE (TYPE_MODE (TREE_TYPE (op0
))))
6056 /* ... or signedness changes for division or modulus,
6057 then we cannot pass through this conversion. */
6058 || (code
!= MULT_EXPR
6059 && (TYPE_UNSIGNED (ctype
)
6060 != TYPE_UNSIGNED (TREE_TYPE (op0
))))))
6063 /* Pass the constant down and see if we can make a simplification. If
6064 we can, replace this expression with the inner simplification for
6065 possible later conversion to our or some other type. */
6066 if ((t2
= fold_convert (TREE_TYPE (op0
), c
)) != 0
6067 && TREE_CODE (t2
) == INTEGER_CST
6068 && !TREE_OVERFLOW (t2
)
6069 && (0 != (t1
= extract_muldiv (op0
, t2
, code
,
6071 ? ctype
: NULL_TREE
,
6072 strict_overflow_p
))))
6077 /* If widening the type changes it from signed to unsigned, then we
6078 must avoid building ABS_EXPR itself as unsigned. */
6079 if (TYPE_UNSIGNED (ctype
) && !TYPE_UNSIGNED (type
))
6081 tree cstype
= (*signed_type_for
) (ctype
);
6082 if ((t1
= extract_muldiv (op0
, c
, code
, cstype
, strict_overflow_p
))
6085 t1
= fold_build1 (tcode
, cstype
, fold_convert (cstype
, t1
));
6086 return fold_convert (ctype
, t1
);
6092 if ((t1
= extract_muldiv (op0
, c
, code
, wide_type
, strict_overflow_p
))
6094 return fold_build1 (tcode
, ctype
, fold_convert (ctype
, t1
));
6097 case MIN_EXPR
: case MAX_EXPR
:
6098 /* If widening the type changes the signedness, then we can't perform
6099 this optimization as that changes the result. */
6100 if (TYPE_UNSIGNED (ctype
) != TYPE_UNSIGNED (type
))
6103 /* MIN (a, b) / 5 -> MIN (a / 5, b / 5) */
6104 sub_strict_overflow_p
= false;
6105 if ((t1
= extract_muldiv (op0
, c
, code
, wide_type
,
6106 &sub_strict_overflow_p
)) != 0
6107 && (t2
= extract_muldiv (op1
, c
, code
, wide_type
,
6108 &sub_strict_overflow_p
)) != 0)
6110 if (tree_int_cst_sgn (c
) < 0)
6111 tcode
= (tcode
== MIN_EXPR
? MAX_EXPR
: MIN_EXPR
);
6112 if (sub_strict_overflow_p
)
6113 *strict_overflow_p
= true;
6114 return fold_build2 (tcode
, ctype
, fold_convert (ctype
, t1
),
6115 fold_convert (ctype
, t2
));
6119 case LSHIFT_EXPR
: case RSHIFT_EXPR
:
6120 /* If the second operand is constant, this is a multiplication
6121 or floor division, by a power of two, so we can treat it that
6122 way unless the multiplier or divisor overflows. Signed
6123 left-shift overflow is implementation-defined rather than
6124 undefined in C90, so do not convert signed left shift into
6126 if (TREE_CODE (op1
) == INTEGER_CST
6127 && (tcode
== RSHIFT_EXPR
|| TYPE_UNSIGNED (TREE_TYPE (op0
)))
6128 /* const_binop may not detect overflow correctly,
6129 so check for it explicitly here. */
6130 && TYPE_PRECISION (TREE_TYPE (size_one_node
)) > TREE_INT_CST_LOW (op1
)
6131 && TREE_INT_CST_HIGH (op1
) == 0
6132 && 0 != (t1
= fold_convert (ctype
,
6133 const_binop (LSHIFT_EXPR
,
6136 && !TREE_OVERFLOW (t1
))
6137 return extract_muldiv (build2 (tcode
== LSHIFT_EXPR
6138 ? MULT_EXPR
: FLOOR_DIV_EXPR
,
6139 ctype
, fold_convert (ctype
, op0
), t1
),
6140 c
, code
, wide_type
, strict_overflow_p
);
6143 case PLUS_EXPR
: case MINUS_EXPR
:
6144 /* See if we can eliminate the operation on both sides. If we can, we
6145 can return a new PLUS or MINUS. If we can't, the only remaining
6146 cases where we can do anything are if the second operand is a
6148 sub_strict_overflow_p
= false;
6149 t1
= extract_muldiv (op0
, c
, code
, wide_type
, &sub_strict_overflow_p
);
6150 t2
= extract_muldiv (op1
, c
, code
, wide_type
, &sub_strict_overflow_p
);
6151 if (t1
!= 0 && t2
!= 0
6152 && (code
== MULT_EXPR
6153 /* If not multiplication, we can only do this if both operands
6154 are divisible by c. */
6155 || (multiple_of_p (ctype
, op0
, c
)
6156 && multiple_of_p (ctype
, op1
, c
))))
6158 if (sub_strict_overflow_p
)
6159 *strict_overflow_p
= true;
6160 return fold_build2 (tcode
, ctype
, fold_convert (ctype
, t1
),
6161 fold_convert (ctype
, t2
));
6164 /* If this was a subtraction, negate OP1 and set it to be an addition.
6165 This simplifies the logic below. */
6166 if (tcode
== MINUS_EXPR
)
6167 tcode
= PLUS_EXPR
, op1
= negate_expr (op1
);
6169 if (TREE_CODE (op1
) != INTEGER_CST
)
6172 /* If either OP1 or C are negative, this optimization is not safe for
6173 some of the division and remainder types while for others we need
6174 to change the code. */
6175 if (tree_int_cst_sgn (op1
) < 0 || tree_int_cst_sgn (c
) < 0)
6177 if (code
== CEIL_DIV_EXPR
)
6178 code
= FLOOR_DIV_EXPR
;
6179 else if (code
== FLOOR_DIV_EXPR
)
6180 code
= CEIL_DIV_EXPR
;
6181 else if (code
!= MULT_EXPR
6182 && code
!= CEIL_MOD_EXPR
&& code
!= FLOOR_MOD_EXPR
)
6186 /* If it's a multiply or a division/modulus operation of a multiple
6187 of our constant, do the operation and verify it doesn't overflow. */
6188 if (code
== MULT_EXPR
6189 || integer_zerop (const_binop (TRUNC_MOD_EXPR
, op1
, c
, 0)))
6191 op1
= const_binop (code
, fold_convert (ctype
, op1
),
6192 fold_convert (ctype
, c
), 0);
6193 /* We allow the constant to overflow with wrapping semantics. */
6195 || (TREE_OVERFLOW (op1
) && !TYPE_OVERFLOW_WRAPS (ctype
)))
6201 /* If we have an unsigned type is not a sizetype, we cannot widen
6202 the operation since it will change the result if the original
6203 computation overflowed. */
6204 if (TYPE_UNSIGNED (ctype
)
6205 && ! (TREE_CODE (ctype
) == INTEGER_TYPE
&& TYPE_IS_SIZETYPE (ctype
))
6209 /* If we were able to eliminate our operation from the first side,
6210 apply our operation to the second side and reform the PLUS. */
6211 if (t1
!= 0 && (TREE_CODE (t1
) != code
|| code
== MULT_EXPR
))
6212 return fold_build2 (tcode
, ctype
, fold_convert (ctype
, t1
), op1
);
6214 /* The last case is if we are a multiply. In that case, we can
6215 apply the distributive law to commute the multiply and addition
6216 if the multiplication of the constants doesn't overflow. */
6217 if (code
== MULT_EXPR
)
6218 return fold_build2 (tcode
, ctype
,
6219 fold_build2 (code
, ctype
,
6220 fold_convert (ctype
, op0
),
6221 fold_convert (ctype
, c
)),
6227 /* We have a special case here if we are doing something like
6228 (C * 8) % 4 since we know that's zero. */
6229 if ((code
== TRUNC_MOD_EXPR
|| code
== CEIL_MOD_EXPR
6230 || code
== FLOOR_MOD_EXPR
|| code
== ROUND_MOD_EXPR
)
6231 && TREE_CODE (TREE_OPERAND (t
, 1)) == INTEGER_CST
6232 && integer_zerop (const_binop (TRUNC_MOD_EXPR
, op1
, c
, 0)))
6233 return omit_one_operand (type
, integer_zero_node
, op0
);
6235 /* ... fall through ... */
6237 case TRUNC_DIV_EXPR
: case CEIL_DIV_EXPR
: case FLOOR_DIV_EXPR
:
6238 case ROUND_DIV_EXPR
: case EXACT_DIV_EXPR
:
6239 /* If we can extract our operation from the LHS, do so and return a
6240 new operation. Likewise for the RHS from a MULT_EXPR. Otherwise,
6241 do something only if the second operand is a constant. */
6243 && (t1
= extract_muldiv (op0
, c
, code
, wide_type
,
6244 strict_overflow_p
)) != 0)
6245 return fold_build2 (tcode
, ctype
, fold_convert (ctype
, t1
),
6246 fold_convert (ctype
, op1
));
6247 else if (tcode
== MULT_EXPR
&& code
== MULT_EXPR
6248 && (t1
= extract_muldiv (op1
, c
, code
, wide_type
,
6249 strict_overflow_p
)) != 0)
6250 return fold_build2 (tcode
, ctype
, fold_convert (ctype
, op0
),
6251 fold_convert (ctype
, t1
));
6252 else if (TREE_CODE (op1
) != INTEGER_CST
)
6255 /* If these are the same operation types, we can associate them
6256 assuming no overflow. */
6258 && 0 != (t1
= const_binop (MULT_EXPR
, fold_convert (ctype
, op1
),
6259 fold_convert (ctype
, c
), 0))
6260 && !TREE_OVERFLOW (t1
))
6261 return fold_build2 (tcode
, ctype
, fold_convert (ctype
, op0
), t1
);
6263 /* If these operations "cancel" each other, we have the main
6264 optimizations of this pass, which occur when either constant is a
6265 multiple of the other, in which case we replace this with either an
6266 operation or CODE or TCODE.
6268 If we have an unsigned type that is not a sizetype, we cannot do
6269 this since it will change the result if the original computation
6271 if ((TYPE_OVERFLOW_UNDEFINED (ctype
)
6272 || (TREE_CODE (ctype
) == INTEGER_TYPE
&& TYPE_IS_SIZETYPE (ctype
)))
6273 && ((code
== MULT_EXPR
&& tcode
== EXACT_DIV_EXPR
)
6274 || (tcode
== MULT_EXPR
6275 && code
!= TRUNC_MOD_EXPR
&& code
!= CEIL_MOD_EXPR
6276 && code
!= FLOOR_MOD_EXPR
&& code
!= ROUND_MOD_EXPR
6277 && code
!= MULT_EXPR
)))
6279 if (integer_zerop (const_binop (TRUNC_MOD_EXPR
, op1
, c
, 0)))
6281 if (TYPE_OVERFLOW_UNDEFINED (ctype
))
6282 *strict_overflow_p
= true;
6283 return fold_build2 (tcode
, ctype
, fold_convert (ctype
, op0
),
6284 fold_convert (ctype
,
6285 const_binop (TRUNC_DIV_EXPR
,
6288 else if (integer_zerop (const_binop (TRUNC_MOD_EXPR
, c
, op1
, 0)))
6290 if (TYPE_OVERFLOW_UNDEFINED (ctype
))
6291 *strict_overflow_p
= true;
6292 return fold_build2 (code
, ctype
, fold_convert (ctype
, op0
),
6293 fold_convert (ctype
,
6294 const_binop (TRUNC_DIV_EXPR
,
6307 /* Return a node which has the indicated constant VALUE (either 0 or
6308 1), and is of the indicated TYPE. */
6311 constant_boolean_node (int value
, tree type
)
6313 if (type
== integer_type_node
)
6314 return value
? integer_one_node
: integer_zero_node
;
6315 else if (type
== boolean_type_node
)
6316 return value
? boolean_true_node
: boolean_false_node
;
6318 return build_int_cst (type
, value
);
6322 /* Return true if expr looks like an ARRAY_REF and set base and
6323 offset to the appropriate trees. If there is no offset,
6324 offset is set to NULL_TREE. Base will be canonicalized to
6325 something you can get the element type from using
6326 TREE_TYPE (TREE_TYPE (base)). Offset will be the offset
6327 in bytes to the base in sizetype. */
6330 extract_array_ref (tree expr
, tree
*base
, tree
*offset
)
6332 /* One canonical form is a PLUS_EXPR with the first
6333 argument being an ADDR_EXPR with a possible NOP_EXPR
6335 if (TREE_CODE (expr
) == POINTER_PLUS_EXPR
)
6337 tree op0
= TREE_OPERAND (expr
, 0);
6338 tree inner_base
, dummy1
;
6339 /* Strip NOP_EXPRs here because the C frontends and/or
6340 folders present us (int *)&x.a p+ 4 possibly. */
6342 if (extract_array_ref (op0
, &inner_base
, &dummy1
))
6345 *offset
= fold_convert (sizetype
, TREE_OPERAND (expr
, 1));
6346 if (dummy1
!= NULL_TREE
)
6347 *offset
= fold_build2 (PLUS_EXPR
, sizetype
,
6352 /* Other canonical form is an ADDR_EXPR of an ARRAY_REF,
6353 which we transform into an ADDR_EXPR with appropriate
6354 offset. For other arguments to the ADDR_EXPR we assume
6355 zero offset and as such do not care about the ADDR_EXPR
6356 type and strip possible nops from it. */
6357 else if (TREE_CODE (expr
) == ADDR_EXPR
)
6359 tree op0
= TREE_OPERAND (expr
, 0);
6360 if (TREE_CODE (op0
) == ARRAY_REF
)
6362 tree idx
= TREE_OPERAND (op0
, 1);
6363 *base
= TREE_OPERAND (op0
, 0);
6364 *offset
= fold_build2 (MULT_EXPR
, TREE_TYPE (idx
), idx
,
6365 array_ref_element_size (op0
));
6366 *offset
= fold_convert (sizetype
, *offset
);
6370 /* Handle array-to-pointer decay as &a. */
6371 if (TREE_CODE (TREE_TYPE (op0
)) == ARRAY_TYPE
)
6372 *base
= TREE_OPERAND (expr
, 0);
6375 *offset
= NULL_TREE
;
6379 /* The next canonical form is a VAR_DECL with POINTER_TYPE. */
6380 else if (SSA_VAR_P (expr
)
6381 && TREE_CODE (TREE_TYPE (expr
)) == POINTER_TYPE
)
6384 *offset
= NULL_TREE
;
6392 /* Transform `a + (b ? x : y)' into `b ? (a + x) : (a + y)'.
6393 Transform, `a + (x < y)' into `(x < y) ? (a + 1) : (a + 0)'. Here
6394 CODE corresponds to the `+', COND to the `(b ? x : y)' or `(x < y)'
6395 expression, and ARG to `a'. If COND_FIRST_P is nonzero, then the
6396 COND is the first argument to CODE; otherwise (as in the example
6397 given here), it is the second argument. TYPE is the type of the
6398 original expression. Return NULL_TREE if no simplification is
6402 fold_binary_op_with_conditional_arg (enum tree_code code
,
6403 tree type
, tree op0
, tree op1
,
6404 tree cond
, tree arg
, int cond_first_p
)
6406 tree cond_type
= cond_first_p
? TREE_TYPE (op0
) : TREE_TYPE (op1
);
6407 tree arg_type
= cond_first_p
? TREE_TYPE (op1
) : TREE_TYPE (op0
);
6408 tree test
, true_value
, false_value
;
6409 tree lhs
= NULL_TREE
;
6410 tree rhs
= NULL_TREE
;
6412 /* This transformation is only worthwhile if we don't have to wrap
6413 arg in a SAVE_EXPR, and the operation can be simplified on at least
6414 one of the branches once its pushed inside the COND_EXPR. */
6415 if (!TREE_CONSTANT (arg
))
6418 if (TREE_CODE (cond
) == COND_EXPR
)
6420 test
= TREE_OPERAND (cond
, 0);
6421 true_value
= TREE_OPERAND (cond
, 1);
6422 false_value
= TREE_OPERAND (cond
, 2);
6423 /* If this operand throws an expression, then it does not make
6424 sense to try to perform a logical or arithmetic operation
6426 if (VOID_TYPE_P (TREE_TYPE (true_value
)))
6428 if (VOID_TYPE_P (TREE_TYPE (false_value
)))
6433 tree testtype
= TREE_TYPE (cond
);
6435 true_value
= constant_boolean_node (true, testtype
);
6436 false_value
= constant_boolean_node (false, testtype
);
6439 arg
= fold_convert (arg_type
, arg
);
6442 true_value
= fold_convert (cond_type
, true_value
);
6444 lhs
= fold_build2 (code
, type
, true_value
, arg
);
6446 lhs
= fold_build2 (code
, type
, arg
, true_value
);
6450 false_value
= fold_convert (cond_type
, false_value
);
6452 rhs
= fold_build2 (code
, type
, false_value
, arg
);
6454 rhs
= fold_build2 (code
, type
, arg
, false_value
);
6457 test
= fold_build3 (COND_EXPR
, type
, test
, lhs
, rhs
);
6458 return fold_convert (type
, test
);
6462 /* Subroutine of fold() that checks for the addition of +/- 0.0.
6464 If !NEGATE, return true if ADDEND is +/-0.0 and, for all X of type
6465 TYPE, X + ADDEND is the same as X. If NEGATE, return true if X -
6466 ADDEND is the same as X.
6468 X + 0 and X - 0 both give X when X is NaN, infinite, or nonzero
6469 and finite. The problematic cases are when X is zero, and its mode
6470 has signed zeros. In the case of rounding towards -infinity,
6471 X - 0 is not the same as X because 0 - 0 is -0. In other rounding
6472 modes, X + 0 is not the same as X because -0 + 0 is 0. */
6475 fold_real_zero_addition_p (const_tree type
, const_tree addend
, int negate
)
6477 if (!real_zerop (addend
))
6480 /* Don't allow the fold with -fsignaling-nans. */
6481 if (HONOR_SNANS (TYPE_MODE (type
)))
6484 /* Allow the fold if zeros aren't signed, or their sign isn't important. */
6485 if (!HONOR_SIGNED_ZEROS (TYPE_MODE (type
)))
6488 /* Treat x + -0 as x - 0 and x - -0 as x + 0. */
6489 if (TREE_CODE (addend
) == REAL_CST
6490 && REAL_VALUE_MINUS_ZERO (TREE_REAL_CST (addend
)))
6493 /* The mode has signed zeros, and we have to honor their sign.
6494 In this situation, there is only one case we can return true for.
6495 X - 0 is the same as X unless rounding towards -infinity is
6497 return negate
&& !HONOR_SIGN_DEPENDENT_ROUNDING (TYPE_MODE (type
));
6500 /* Subroutine of fold() that checks comparisons of built-in math
6501 functions against real constants.
6503 FCODE is the DECL_FUNCTION_CODE of the built-in, CODE is the comparison
6504 operator: EQ_EXPR, NE_EXPR, GT_EXPR, LT_EXPR, GE_EXPR or LE_EXPR. TYPE
6505 is the type of the result and ARG0 and ARG1 are the operands of the
6506 comparison. ARG1 must be a TREE_REAL_CST.
6508 The function returns the constant folded tree if a simplification
6509 can be made, and NULL_TREE otherwise. */
6512 fold_mathfn_compare (enum built_in_function fcode
, enum tree_code code
,
6513 tree type
, tree arg0
, tree arg1
)
6517 if (BUILTIN_SQRT_P (fcode
))
6519 tree arg
= CALL_EXPR_ARG (arg0
, 0);
6520 enum machine_mode mode
= TYPE_MODE (TREE_TYPE (arg0
));
6522 c
= TREE_REAL_CST (arg1
);
6523 if (REAL_VALUE_NEGATIVE (c
))
6525 /* sqrt(x) < y is always false, if y is negative. */
6526 if (code
== EQ_EXPR
|| code
== LT_EXPR
|| code
== LE_EXPR
)
6527 return omit_one_operand (type
, integer_zero_node
, arg
);
6529 /* sqrt(x) > y is always true, if y is negative and we
6530 don't care about NaNs, i.e. negative values of x. */
6531 if (code
== NE_EXPR
|| !HONOR_NANS (mode
))
6532 return omit_one_operand (type
, integer_one_node
, arg
);
6534 /* sqrt(x) > y is the same as x >= 0, if y is negative. */
6535 return fold_build2 (GE_EXPR
, type
, arg
,
6536 build_real (TREE_TYPE (arg
), dconst0
));
6538 else if (code
== GT_EXPR
|| code
== GE_EXPR
)
6542 REAL_ARITHMETIC (c2
, MULT_EXPR
, c
, c
);
6543 real_convert (&c2
, mode
, &c2
);
6545 if (REAL_VALUE_ISINF (c2
))
6547 /* sqrt(x) > y is x == +Inf, when y is very large. */
6548 if (HONOR_INFINITIES (mode
))
6549 return fold_build2 (EQ_EXPR
, type
, arg
,
6550 build_real (TREE_TYPE (arg
), c2
));
6552 /* sqrt(x) > y is always false, when y is very large
6553 and we don't care about infinities. */
6554 return omit_one_operand (type
, integer_zero_node
, arg
);
6557 /* sqrt(x) > c is the same as x > c*c. */
6558 return fold_build2 (code
, type
, arg
,
6559 build_real (TREE_TYPE (arg
), c2
));
6561 else if (code
== LT_EXPR
|| code
== LE_EXPR
)
6565 REAL_ARITHMETIC (c2
, MULT_EXPR
, c
, c
);
6566 real_convert (&c2
, mode
, &c2
);
6568 if (REAL_VALUE_ISINF (c2
))
6570 /* sqrt(x) < y is always true, when y is a very large
6571 value and we don't care about NaNs or Infinities. */
6572 if (! HONOR_NANS (mode
) && ! HONOR_INFINITIES (mode
))
6573 return omit_one_operand (type
, integer_one_node
, arg
);
6575 /* sqrt(x) < y is x != +Inf when y is very large and we
6576 don't care about NaNs. */
6577 if (! HONOR_NANS (mode
))
6578 return fold_build2 (NE_EXPR
, type
, arg
,
6579 build_real (TREE_TYPE (arg
), c2
));
6581 /* sqrt(x) < y is x >= 0 when y is very large and we
6582 don't care about Infinities. */
6583 if (! HONOR_INFINITIES (mode
))
6584 return fold_build2 (GE_EXPR
, type
, arg
,
6585 build_real (TREE_TYPE (arg
), dconst0
));
6587 /* sqrt(x) < y is x >= 0 && x != +Inf, when y is large. */
6588 if (lang_hooks
.decls
.global_bindings_p () != 0
6589 || CONTAINS_PLACEHOLDER_P (arg
))
6592 arg
= save_expr (arg
);
6593 return fold_build2 (TRUTH_ANDIF_EXPR
, type
,
6594 fold_build2 (GE_EXPR
, type
, arg
,
6595 build_real (TREE_TYPE (arg
),
6597 fold_build2 (NE_EXPR
, type
, arg
,
6598 build_real (TREE_TYPE (arg
),
6602 /* sqrt(x) < c is the same as x < c*c, if we ignore NaNs. */
6603 if (! HONOR_NANS (mode
))
6604 return fold_build2 (code
, type
, arg
,
6605 build_real (TREE_TYPE (arg
), c2
));
6607 /* sqrt(x) < c is the same as x >= 0 && x < c*c. */
6608 if (lang_hooks
.decls
.global_bindings_p () == 0
6609 && ! CONTAINS_PLACEHOLDER_P (arg
))
6611 arg
= save_expr (arg
);
6612 return fold_build2 (TRUTH_ANDIF_EXPR
, type
,
6613 fold_build2 (GE_EXPR
, type
, arg
,
6614 build_real (TREE_TYPE (arg
),
6616 fold_build2 (code
, type
, arg
,
6617 build_real (TREE_TYPE (arg
),
6626 /* Subroutine of fold() that optimizes comparisons against Infinities,
6627 either +Inf or -Inf.
6629 CODE is the comparison operator: EQ_EXPR, NE_EXPR, GT_EXPR, LT_EXPR,
6630 GE_EXPR or LE_EXPR. TYPE is the type of the result and ARG0 and ARG1
6631 are the operands of the comparison. ARG1 must be a TREE_REAL_CST.
6633 The function returns the constant folded tree if a simplification
6634 can be made, and NULL_TREE otherwise. */
6637 fold_inf_compare (enum tree_code code
, tree type
, tree arg0
, tree arg1
)
6639 enum machine_mode mode
;
6640 REAL_VALUE_TYPE max
;
6644 mode
= TYPE_MODE (TREE_TYPE (arg0
));
6646 /* For negative infinity swap the sense of the comparison. */
6647 neg
= REAL_VALUE_NEGATIVE (TREE_REAL_CST (arg1
));
6649 code
= swap_tree_comparison (code
);
6654 /* x > +Inf is always false, if with ignore sNANs. */
6655 if (HONOR_SNANS (mode
))
6657 return omit_one_operand (type
, integer_zero_node
, arg0
);
6660 /* x <= +Inf is always true, if we don't case about NaNs. */
6661 if (! HONOR_NANS (mode
))
6662 return omit_one_operand (type
, integer_one_node
, arg0
);
6664 /* x <= +Inf is the same as x == x, i.e. isfinite(x). */
6665 if (lang_hooks
.decls
.global_bindings_p () == 0
6666 && ! CONTAINS_PLACEHOLDER_P (arg0
))
6668 arg0
= save_expr (arg0
);
6669 return fold_build2 (EQ_EXPR
, type
, arg0
, arg0
);
6675 /* x == +Inf and x >= +Inf are always equal to x > DBL_MAX. */
6676 real_maxval (&max
, neg
, mode
);
6677 return fold_build2 (neg
? LT_EXPR
: GT_EXPR
, type
,
6678 arg0
, build_real (TREE_TYPE (arg0
), max
));
6681 /* x < +Inf is always equal to x <= DBL_MAX. */
6682 real_maxval (&max
, neg
, mode
);
6683 return fold_build2 (neg
? GE_EXPR
: LE_EXPR
, type
,
6684 arg0
, build_real (TREE_TYPE (arg0
), max
));
6687 /* x != +Inf is always equal to !(x > DBL_MAX). */
6688 real_maxval (&max
, neg
, mode
);
6689 if (! HONOR_NANS (mode
))
6690 return fold_build2 (neg
? GE_EXPR
: LE_EXPR
, type
,
6691 arg0
, build_real (TREE_TYPE (arg0
), max
));
6693 temp
= fold_build2 (neg
? LT_EXPR
: GT_EXPR
, type
,
6694 arg0
, build_real (TREE_TYPE (arg0
), max
));
6695 return fold_build1 (TRUTH_NOT_EXPR
, type
, temp
);
6704 /* Subroutine of fold() that optimizes comparisons of a division by
6705 a nonzero integer constant against an integer constant, i.e.
6708 CODE is the comparison operator: EQ_EXPR, NE_EXPR, GT_EXPR, LT_EXPR,
6709 GE_EXPR or LE_EXPR. TYPE is the type of the result and ARG0 and ARG1
6710 are the operands of the comparison. ARG1 must be a TREE_REAL_CST.
6712 The function returns the constant folded tree if a simplification
6713 can be made, and NULL_TREE otherwise. */
6716 fold_div_compare (enum tree_code code
, tree type
, tree arg0
, tree arg1
)
6718 tree prod
, tmp
, hi
, lo
;
6719 tree arg00
= TREE_OPERAND (arg0
, 0);
6720 tree arg01
= TREE_OPERAND (arg0
, 1);
6721 unsigned HOST_WIDE_INT lpart
;
6722 HOST_WIDE_INT hpart
;
6723 bool unsigned_p
= TYPE_UNSIGNED (TREE_TYPE (arg0
));
6727 /* We have to do this the hard way to detect unsigned overflow.
6728 prod = int_const_binop (MULT_EXPR, arg01, arg1, 0); */
6729 overflow
= mul_double_with_sign (TREE_INT_CST_LOW (arg01
),
6730 TREE_INT_CST_HIGH (arg01
),
6731 TREE_INT_CST_LOW (arg1
),
6732 TREE_INT_CST_HIGH (arg1
),
6733 &lpart
, &hpart
, unsigned_p
);
6734 prod
= force_fit_type_double (TREE_TYPE (arg00
), lpart
, hpart
,
6736 neg_overflow
= false;
6740 tmp
= int_const_binop (MINUS_EXPR
, arg01
,
6741 build_int_cst (TREE_TYPE (arg01
), 1), 0);
6744 /* Likewise hi = int_const_binop (PLUS_EXPR, prod, tmp, 0). */
6745 overflow
= add_double_with_sign (TREE_INT_CST_LOW (prod
),
6746 TREE_INT_CST_HIGH (prod
),
6747 TREE_INT_CST_LOW (tmp
),
6748 TREE_INT_CST_HIGH (tmp
),
6749 &lpart
, &hpart
, unsigned_p
);
6750 hi
= force_fit_type_double (TREE_TYPE (arg00
), lpart
, hpart
,
6751 -1, overflow
| TREE_OVERFLOW (prod
));
6753 else if (tree_int_cst_sgn (arg01
) >= 0)
6755 tmp
= int_const_binop (MINUS_EXPR
, arg01
,
6756 build_int_cst (TREE_TYPE (arg01
), 1), 0);
6757 switch (tree_int_cst_sgn (arg1
))
6760 neg_overflow
= true;
6761 lo
= int_const_binop (MINUS_EXPR
, prod
, tmp
, 0);
6766 lo
= fold_negate_const (tmp
, TREE_TYPE (arg0
));
6771 hi
= int_const_binop (PLUS_EXPR
, prod
, tmp
, 0);
6781 /* A negative divisor reverses the relational operators. */
6782 code
= swap_tree_comparison (code
);
6784 tmp
= int_const_binop (PLUS_EXPR
, arg01
,
6785 build_int_cst (TREE_TYPE (arg01
), 1), 0);
6786 switch (tree_int_cst_sgn (arg1
))
6789 hi
= int_const_binop (MINUS_EXPR
, prod
, tmp
, 0);
6794 hi
= fold_negate_const (tmp
, TREE_TYPE (arg0
));
6799 neg_overflow
= true;
6800 lo
= int_const_binop (PLUS_EXPR
, prod
, tmp
, 0);
6812 if (TREE_OVERFLOW (lo
) && TREE_OVERFLOW (hi
))
6813 return omit_one_operand (type
, integer_zero_node
, arg00
);
6814 if (TREE_OVERFLOW (hi
))
6815 return fold_build2 (GE_EXPR
, type
, arg00
, lo
);
6816 if (TREE_OVERFLOW (lo
))
6817 return fold_build2 (LE_EXPR
, type
, arg00
, hi
);
6818 return build_range_check (type
, arg00
, 1, lo
, hi
);
6821 if (TREE_OVERFLOW (lo
) && TREE_OVERFLOW (hi
))
6822 return omit_one_operand (type
, integer_one_node
, arg00
);
6823 if (TREE_OVERFLOW (hi
))
6824 return fold_build2 (LT_EXPR
, type
, arg00
, lo
);
6825 if (TREE_OVERFLOW (lo
))
6826 return fold_build2 (GT_EXPR
, type
, arg00
, hi
);
6827 return build_range_check (type
, arg00
, 0, lo
, hi
);
6830 if (TREE_OVERFLOW (lo
))
6832 tmp
= neg_overflow
? integer_zero_node
: integer_one_node
;
6833 return omit_one_operand (type
, tmp
, arg00
);
6835 return fold_build2 (LT_EXPR
, type
, arg00
, lo
);
6838 if (TREE_OVERFLOW (hi
))
6840 tmp
= neg_overflow
? integer_zero_node
: integer_one_node
;
6841 return omit_one_operand (type
, tmp
, arg00
);
6843 return fold_build2 (LE_EXPR
, type
, arg00
, hi
);
6846 if (TREE_OVERFLOW (hi
))
6848 tmp
= neg_overflow
? integer_one_node
: integer_zero_node
;
6849 return omit_one_operand (type
, tmp
, arg00
);
6851 return fold_build2 (GT_EXPR
, type
, arg00
, hi
);
6854 if (TREE_OVERFLOW (lo
))
6856 tmp
= neg_overflow
? integer_one_node
: integer_zero_node
;
6857 return omit_one_operand (type
, tmp
, arg00
);
6859 return fold_build2 (GE_EXPR
, type
, arg00
, lo
);
6869 /* If CODE with arguments ARG0 and ARG1 represents a single bit
6870 equality/inequality test, then return a simplified form of the test
6871 using a sign testing. Otherwise return NULL. TYPE is the desired
6875 fold_single_bit_test_into_sign_test (enum tree_code code
, tree arg0
, tree arg1
,
6878 /* If this is testing a single bit, we can optimize the test. */
6879 if ((code
== NE_EXPR
|| code
== EQ_EXPR
)
6880 && TREE_CODE (arg0
) == BIT_AND_EXPR
&& integer_zerop (arg1
)
6881 && integer_pow2p (TREE_OPERAND (arg0
, 1)))
6883 /* If we have (A & C) != 0 where C is the sign bit of A, convert
6884 this into A < 0. Similarly for (A & C) == 0 into A >= 0. */
6885 tree arg00
= sign_bit_p (TREE_OPERAND (arg0
, 0), TREE_OPERAND (arg0
, 1));
6887 if (arg00
!= NULL_TREE
6888 /* This is only a win if casting to a signed type is cheap,
6889 i.e. when arg00's type is not a partial mode. */
6890 && TYPE_PRECISION (TREE_TYPE (arg00
))
6891 == GET_MODE_BITSIZE (TYPE_MODE (TREE_TYPE (arg00
))))
6893 tree stype
= signed_type_for (TREE_TYPE (arg00
));
6894 return fold_build2 (code
== EQ_EXPR
? GE_EXPR
: LT_EXPR
,
6895 result_type
, fold_convert (stype
, arg00
),
6896 build_int_cst (stype
, 0));
6903 /* If CODE with arguments ARG0 and ARG1 represents a single bit
6904 equality/inequality test, then return a simplified form of
6905 the test using shifts and logical operations. Otherwise return
6906 NULL. TYPE is the desired result type. */
6909 fold_single_bit_test (enum tree_code code
, tree arg0
, tree arg1
,
6912 /* If this is testing a single bit, we can optimize the test. */
6913 if ((code
== NE_EXPR
|| code
== EQ_EXPR
)
6914 && TREE_CODE (arg0
) == BIT_AND_EXPR
&& integer_zerop (arg1
)
6915 && integer_pow2p (TREE_OPERAND (arg0
, 1)))
6917 tree inner
= TREE_OPERAND (arg0
, 0);
6918 tree type
= TREE_TYPE (arg0
);
6919 int bitnum
= tree_log2 (TREE_OPERAND (arg0
, 1));
6920 enum machine_mode operand_mode
= TYPE_MODE (type
);
6922 tree signed_type
, unsigned_type
, intermediate_type
;
6925 /* First, see if we can fold the single bit test into a sign-bit
6927 tem
= fold_single_bit_test_into_sign_test (code
, arg0
, arg1
,
6932 /* Otherwise we have (A & C) != 0 where C is a single bit,
6933 convert that into ((A >> C2) & 1). Where C2 = log2(C).
6934 Similarly for (A & C) == 0. */
6936 /* If INNER is a right shift of a constant and it plus BITNUM does
6937 not overflow, adjust BITNUM and INNER. */
6938 if (TREE_CODE (inner
) == RSHIFT_EXPR
6939 && TREE_CODE (TREE_OPERAND (inner
, 1)) == INTEGER_CST
6940 && TREE_INT_CST_HIGH (TREE_OPERAND (inner
, 1)) == 0
6941 && bitnum
< TYPE_PRECISION (type
)
6942 && 0 > compare_tree_int (TREE_OPERAND (inner
, 1),
6943 bitnum
- TYPE_PRECISION (type
)))
6945 bitnum
+= TREE_INT_CST_LOW (TREE_OPERAND (inner
, 1));
6946 inner
= TREE_OPERAND (inner
, 0);
6949 /* If we are going to be able to omit the AND below, we must do our
6950 operations as unsigned. If we must use the AND, we have a choice.
6951 Normally unsigned is faster, but for some machines signed is. */
6952 #ifdef LOAD_EXTEND_OP
6953 ops_unsigned
= (LOAD_EXTEND_OP (operand_mode
) == SIGN_EXTEND
6954 && !flag_syntax_only
) ? 0 : 1;
6959 signed_type
= lang_hooks
.types
.type_for_mode (operand_mode
, 0);
6960 unsigned_type
= lang_hooks
.types
.type_for_mode (operand_mode
, 1);
6961 intermediate_type
= ops_unsigned
? unsigned_type
: signed_type
;
6962 inner
= fold_convert (intermediate_type
, inner
);
6965 inner
= build2 (RSHIFT_EXPR
, intermediate_type
,
6966 inner
, size_int (bitnum
));
6968 one
= build_int_cst (intermediate_type
, 1);
6970 if (code
== EQ_EXPR
)
6971 inner
= fold_build2 (BIT_XOR_EXPR
, intermediate_type
, inner
, one
);
6973 /* Put the AND last so it can combine with more things. */
6974 inner
= build2 (BIT_AND_EXPR
, intermediate_type
, inner
, one
);
6976 /* Make sure to return the proper type. */
6977 inner
= fold_convert (result_type
, inner
);
6984 /* Check whether we are allowed to reorder operands arg0 and arg1,
6985 such that the evaluation of arg1 occurs before arg0. */
6988 reorder_operands_p (const_tree arg0
, const_tree arg1
)
6990 if (! flag_evaluation_order
)
6992 if (TREE_CONSTANT (arg0
) || TREE_CONSTANT (arg1
))
6994 return ! TREE_SIDE_EFFECTS (arg0
)
6995 && ! TREE_SIDE_EFFECTS (arg1
);
6998 /* Test whether it is preferable two swap two operands, ARG0 and
6999 ARG1, for example because ARG0 is an integer constant and ARG1
7000 isn't. If REORDER is true, only recommend swapping if we can
7001 evaluate the operands in reverse order. */
7004 tree_swap_operands_p (const_tree arg0
, const_tree arg1
, bool reorder
)
7006 STRIP_SIGN_NOPS (arg0
);
7007 STRIP_SIGN_NOPS (arg1
);
7009 if (TREE_CODE (arg1
) == INTEGER_CST
)
7011 if (TREE_CODE (arg0
) == INTEGER_CST
)
7014 if (TREE_CODE (arg1
) == REAL_CST
)
7016 if (TREE_CODE (arg0
) == REAL_CST
)
7019 if (TREE_CODE (arg1
) == FIXED_CST
)
7021 if (TREE_CODE (arg0
) == FIXED_CST
)
7024 if (TREE_CODE (arg1
) == COMPLEX_CST
)
7026 if (TREE_CODE (arg0
) == COMPLEX_CST
)
7029 if (TREE_CONSTANT (arg1
))
7031 if (TREE_CONSTANT (arg0
))
7037 if (reorder
&& flag_evaluation_order
7038 && (TREE_SIDE_EFFECTS (arg0
) || TREE_SIDE_EFFECTS (arg1
)))
7041 /* It is preferable to swap two SSA_NAME to ensure a canonical form
7042 for commutative and comparison operators. Ensuring a canonical
7043 form allows the optimizers to find additional redundancies without
7044 having to explicitly check for both orderings. */
7045 if (TREE_CODE (arg0
) == SSA_NAME
7046 && TREE_CODE (arg1
) == SSA_NAME
7047 && SSA_NAME_VERSION (arg0
) > SSA_NAME_VERSION (arg1
))
7050 /* Put SSA_NAMEs last. */
7051 if (TREE_CODE (arg1
) == SSA_NAME
)
7053 if (TREE_CODE (arg0
) == SSA_NAME
)
7056 /* Put variables last. */
7065 /* Fold comparison ARG0 CODE ARG1 (with result in TYPE), where
7066 ARG0 is extended to a wider type. */
7069 fold_widened_comparison (enum tree_code code
, tree type
, tree arg0
, tree arg1
)
7071 tree arg0_unw
= get_unwidened (arg0
, NULL_TREE
);
7073 tree shorter_type
, outer_type
;
7077 if (arg0_unw
== arg0
)
7079 shorter_type
= TREE_TYPE (arg0_unw
);
7081 #ifdef HAVE_canonicalize_funcptr_for_compare
7082 /* Disable this optimization if we're casting a function pointer
7083 type on targets that require function pointer canonicalization. */
7084 if (HAVE_canonicalize_funcptr_for_compare
7085 && TREE_CODE (shorter_type
) == POINTER_TYPE
7086 && TREE_CODE (TREE_TYPE (shorter_type
)) == FUNCTION_TYPE
)
7090 if (TYPE_PRECISION (TREE_TYPE (arg0
)) <= TYPE_PRECISION (shorter_type
))
7093 arg1_unw
= get_unwidened (arg1
, shorter_type
);
7095 /* If possible, express the comparison in the shorter mode. */
7096 if ((code
== EQ_EXPR
|| code
== NE_EXPR
7097 || TYPE_UNSIGNED (TREE_TYPE (arg0
)) == TYPE_UNSIGNED (shorter_type
))
7098 && (TREE_TYPE (arg1_unw
) == shorter_type
7099 || (TREE_CODE (arg1_unw
) == INTEGER_CST
7100 && (TREE_CODE (shorter_type
) == INTEGER_TYPE
7101 || TREE_CODE (shorter_type
) == BOOLEAN_TYPE
)
7102 && int_fits_type_p (arg1_unw
, shorter_type
))))
7103 return fold_build2 (code
, type
, arg0_unw
,
7104 fold_convert (shorter_type
, arg1_unw
));
7106 if (TREE_CODE (arg1_unw
) != INTEGER_CST
7107 || TREE_CODE (shorter_type
) != INTEGER_TYPE
7108 || !int_fits_type_p (arg1_unw
, shorter_type
))
7111 /* If we are comparing with the integer that does not fit into the range
7112 of the shorter type, the result is known. */
7113 outer_type
= TREE_TYPE (arg1_unw
);
7114 min
= lower_bound_in_type (outer_type
, shorter_type
);
7115 max
= upper_bound_in_type (outer_type
, shorter_type
);
7117 above
= integer_nonzerop (fold_relational_const (LT_EXPR
, type
,
7119 below
= integer_nonzerop (fold_relational_const (LT_EXPR
, type
,
7126 return omit_one_operand (type
, integer_zero_node
, arg0
);
7131 return omit_one_operand (type
, integer_one_node
, arg0
);
7137 return omit_one_operand (type
, integer_one_node
, arg0
);
7139 return omit_one_operand (type
, integer_zero_node
, arg0
);
7144 return omit_one_operand (type
, integer_zero_node
, arg0
);
7146 return omit_one_operand (type
, integer_one_node
, arg0
);
7155 /* Fold comparison ARG0 CODE ARG1 (with result in TYPE), where for
7156 ARG0 just the signedness is changed. */
7159 fold_sign_changed_comparison (enum tree_code code
, tree type
,
7160 tree arg0
, tree arg1
)
7163 tree inner_type
, outer_type
;
7165 if (TREE_CODE (arg0
) != NOP_EXPR
7166 && TREE_CODE (arg0
) != CONVERT_EXPR
)
7169 outer_type
= TREE_TYPE (arg0
);
7170 arg0_inner
= TREE_OPERAND (arg0
, 0);
7171 inner_type
= TREE_TYPE (arg0_inner
);
7173 #ifdef HAVE_canonicalize_funcptr_for_compare
7174 /* Disable this optimization if we're casting a function pointer
7175 type on targets that require function pointer canonicalization. */
7176 if (HAVE_canonicalize_funcptr_for_compare
7177 && TREE_CODE (inner_type
) == POINTER_TYPE
7178 && TREE_CODE (TREE_TYPE (inner_type
)) == FUNCTION_TYPE
)
7182 if (TYPE_PRECISION (inner_type
) != TYPE_PRECISION (outer_type
))
7185 if (TREE_CODE (arg1
) != INTEGER_CST
7186 && !((TREE_CODE (arg1
) == NOP_EXPR
7187 || TREE_CODE (arg1
) == CONVERT_EXPR
)
7188 && TREE_TYPE (TREE_OPERAND (arg1
, 0)) == inner_type
))
7191 if (TYPE_UNSIGNED (inner_type
) != TYPE_UNSIGNED (outer_type
)
7196 if (TREE_CODE (arg1
) == INTEGER_CST
)
7197 arg1
= force_fit_type_double (inner_type
, TREE_INT_CST_LOW (arg1
),
7198 TREE_INT_CST_HIGH (arg1
), 0,
7199 TREE_OVERFLOW (arg1
));
7201 arg1
= fold_convert (inner_type
, arg1
);
7203 return fold_build2 (code
, type
, arg0_inner
, arg1
);
7206 /* Tries to replace &a[idx] p+ s * delta with &a[idx + delta], if s is
7207 step of the array. Reconstructs s and delta in the case of s * delta
7208 being an integer constant (and thus already folded).
7209 ADDR is the address. MULT is the multiplicative expression.
7210 If the function succeeds, the new address expression is returned. Otherwise
7211 NULL_TREE is returned. */
7214 try_move_mult_to_index (tree addr
, tree op1
)
7216 tree s
, delta
, step
;
7217 tree ref
= TREE_OPERAND (addr
, 0), pref
;
7222 /* Strip the nops that might be added when converting op1 to sizetype. */
7225 /* Canonicalize op1 into a possibly non-constant delta
7226 and an INTEGER_CST s. */
7227 if (TREE_CODE (op1
) == MULT_EXPR
)
7229 tree arg0
= TREE_OPERAND (op1
, 0), arg1
= TREE_OPERAND (op1
, 1);
7234 if (TREE_CODE (arg0
) == INTEGER_CST
)
7239 else if (TREE_CODE (arg1
) == INTEGER_CST
)
7247 else if (TREE_CODE (op1
) == INTEGER_CST
)
7254 /* Simulate we are delta * 1. */
7256 s
= integer_one_node
;
7259 for (;; ref
= TREE_OPERAND (ref
, 0))
7261 if (TREE_CODE (ref
) == ARRAY_REF
)
7263 /* Remember if this was a multi-dimensional array. */
7264 if (TREE_CODE (TREE_OPERAND (ref
, 0)) == ARRAY_REF
)
7267 itype
= TYPE_DOMAIN (TREE_TYPE (TREE_OPERAND (ref
, 0)));
7271 step
= array_ref_element_size (ref
);
7272 if (TREE_CODE (step
) != INTEGER_CST
)
7277 if (! tree_int_cst_equal (step
, s
))
7282 /* Try if delta is a multiple of step. */
7283 tree tmp
= div_if_zero_remainder (EXACT_DIV_EXPR
, delta
, step
);
7289 /* Only fold here if we can verify we do not overflow one
7290 dimension of a multi-dimensional array. */
7295 if (TREE_CODE (TREE_OPERAND (ref
, 1)) != INTEGER_CST
7296 || !INTEGRAL_TYPE_P (itype
)
7297 || !TYPE_MAX_VALUE (itype
)
7298 || TREE_CODE (TYPE_MAX_VALUE (itype
)) != INTEGER_CST
)
7301 tmp
= fold_binary (PLUS_EXPR
, itype
,
7302 fold_convert (itype
,
7303 TREE_OPERAND (ref
, 1)),
7304 fold_convert (itype
, delta
));
7306 || TREE_CODE (tmp
) != INTEGER_CST
7307 || tree_int_cst_lt (TYPE_MAX_VALUE (itype
), tmp
))
7316 if (!handled_component_p (ref
))
7320 /* We found the suitable array reference. So copy everything up to it,
7321 and replace the index. */
7323 pref
= TREE_OPERAND (addr
, 0);
7324 ret
= copy_node (pref
);
7329 pref
= TREE_OPERAND (pref
, 0);
7330 TREE_OPERAND (pos
, 0) = copy_node (pref
);
7331 pos
= TREE_OPERAND (pos
, 0);
7334 TREE_OPERAND (pos
, 1) = fold_build2 (PLUS_EXPR
, itype
,
7335 fold_convert (itype
,
7336 TREE_OPERAND (pos
, 1)),
7337 fold_convert (itype
, delta
));
7339 return fold_build1 (ADDR_EXPR
, TREE_TYPE (addr
), ret
);
7343 /* Fold A < X && A + 1 > Y to A < X && A >= Y. Normally A + 1 > Y
7344 means A >= Y && A != MAX, but in this case we know that
7345 A < X <= MAX. INEQ is A + 1 > Y, BOUND is A < X. */
7348 fold_to_nonsharp_ineq_using_bound (tree ineq
, tree bound
)
7350 tree a
, typea
, type
= TREE_TYPE (ineq
), a1
, diff
, y
;
7352 if (TREE_CODE (bound
) == LT_EXPR
)
7353 a
= TREE_OPERAND (bound
, 0);
7354 else if (TREE_CODE (bound
) == GT_EXPR
)
7355 a
= TREE_OPERAND (bound
, 1);
7359 typea
= TREE_TYPE (a
);
7360 if (!INTEGRAL_TYPE_P (typea
)
7361 && !POINTER_TYPE_P (typea
))
7364 if (TREE_CODE (ineq
) == LT_EXPR
)
7366 a1
= TREE_OPERAND (ineq
, 1);
7367 y
= TREE_OPERAND (ineq
, 0);
7369 else if (TREE_CODE (ineq
) == GT_EXPR
)
7371 a1
= TREE_OPERAND (ineq
, 0);
7372 y
= TREE_OPERAND (ineq
, 1);
7377 if (TREE_TYPE (a1
) != typea
)
7380 if (POINTER_TYPE_P (typea
))
7382 /* Convert the pointer types into integer before taking the difference. */
7383 tree ta
= fold_convert (ssizetype
, a
);
7384 tree ta1
= fold_convert (ssizetype
, a1
);
7385 diff
= fold_binary (MINUS_EXPR
, ssizetype
, ta1
, ta
);
7388 diff
= fold_binary (MINUS_EXPR
, typea
, a1
, a
);
7390 if (!diff
|| !integer_onep (diff
))
7393 return fold_build2 (GE_EXPR
, type
, a
, y
);
7396 /* Fold a sum or difference of at least one multiplication.
7397 Returns the folded tree or NULL if no simplification could be made. */
7400 fold_plusminus_mult_expr (enum tree_code code
, tree type
, tree arg0
, tree arg1
)
7402 tree arg00
, arg01
, arg10
, arg11
;
7403 tree alt0
= NULL_TREE
, alt1
= NULL_TREE
, same
;
7405 /* (A * C) +- (B * C) -> (A+-B) * C.
7406 (A * C) +- A -> A * (C+-1).
7407 We are most concerned about the case where C is a constant,
7408 but other combinations show up during loop reduction. Since
7409 it is not difficult, try all four possibilities. */
7411 if (TREE_CODE (arg0
) == MULT_EXPR
)
7413 arg00
= TREE_OPERAND (arg0
, 0);
7414 arg01
= TREE_OPERAND (arg0
, 1);
7416 else if (TREE_CODE (arg0
) == INTEGER_CST
)
7418 arg00
= build_one_cst (type
);
7423 /* We cannot generate constant 1 for fract. */
7424 if (ALL_FRACT_MODE_P (TYPE_MODE (type
)))
7427 arg01
= build_one_cst (type
);
7429 if (TREE_CODE (arg1
) == MULT_EXPR
)
7431 arg10
= TREE_OPERAND (arg1
, 0);
7432 arg11
= TREE_OPERAND (arg1
, 1);
7434 else if (TREE_CODE (arg1
) == INTEGER_CST
)
7436 arg10
= build_one_cst (type
);
7441 /* We cannot generate constant 1 for fract. */
7442 if (ALL_FRACT_MODE_P (TYPE_MODE (type
)))
7445 arg11
= build_one_cst (type
);
7449 if (operand_equal_p (arg01
, arg11
, 0))
7450 same
= arg01
, alt0
= arg00
, alt1
= arg10
;
7451 else if (operand_equal_p (arg00
, arg10
, 0))
7452 same
= arg00
, alt0
= arg01
, alt1
= arg11
;
7453 else if (operand_equal_p (arg00
, arg11
, 0))
7454 same
= arg00
, alt0
= arg01
, alt1
= arg10
;
7455 else if (operand_equal_p (arg01
, arg10
, 0))
7456 same
= arg01
, alt0
= arg00
, alt1
= arg11
;
7458 /* No identical multiplicands; see if we can find a common
7459 power-of-two factor in non-power-of-two multiplies. This
7460 can help in multi-dimensional array access. */
7461 else if (host_integerp (arg01
, 0)
7462 && host_integerp (arg11
, 0))
7464 HOST_WIDE_INT int01
, int11
, tmp
;
7467 int01
= TREE_INT_CST_LOW (arg01
);
7468 int11
= TREE_INT_CST_LOW (arg11
);
7470 /* Move min of absolute values to int11. */
7471 if ((int01
>= 0 ? int01
: -int01
)
7472 < (int11
>= 0 ? int11
: -int11
))
7474 tmp
= int01
, int01
= int11
, int11
= tmp
;
7475 alt0
= arg00
, arg00
= arg10
, arg10
= alt0
;
7482 if (exact_log2 (abs (int11
)) > 0 && int01
% int11
== 0)
7484 alt0
= fold_build2 (MULT_EXPR
, TREE_TYPE (arg00
), arg00
,
7485 build_int_cst (TREE_TYPE (arg00
),
7490 maybe_same
= alt0
, alt0
= alt1
, alt1
= maybe_same
;
7495 return fold_build2 (MULT_EXPR
, type
,
7496 fold_build2 (code
, type
,
7497 fold_convert (type
, alt0
),
7498 fold_convert (type
, alt1
)),
7499 fold_convert (type
, same
));
7504 /* Subroutine of native_encode_expr. Encode the INTEGER_CST
7505 specified by EXPR into the buffer PTR of length LEN bytes.
7506 Return the number of bytes placed in the buffer, or zero
7510 native_encode_int (const_tree expr
, unsigned char *ptr
, int len
)
7512 tree type
= TREE_TYPE (expr
);
7513 int total_bytes
= GET_MODE_SIZE (TYPE_MODE (type
));
7514 int byte
, offset
, word
, words
;
7515 unsigned char value
;
7517 if (total_bytes
> len
)
7519 words
= total_bytes
/ UNITS_PER_WORD
;
7521 for (byte
= 0; byte
< total_bytes
; byte
++)
7523 int bitpos
= byte
* BITS_PER_UNIT
;
7524 if (bitpos
< HOST_BITS_PER_WIDE_INT
)
7525 value
= (unsigned char) (TREE_INT_CST_LOW (expr
) >> bitpos
);
7527 value
= (unsigned char) (TREE_INT_CST_HIGH (expr
)
7528 >> (bitpos
- HOST_BITS_PER_WIDE_INT
));
7530 if (total_bytes
> UNITS_PER_WORD
)
7532 word
= byte
/ UNITS_PER_WORD
;
7533 if (WORDS_BIG_ENDIAN
)
7534 word
= (words
- 1) - word
;
7535 offset
= word
* UNITS_PER_WORD
;
7536 if (BYTES_BIG_ENDIAN
)
7537 offset
+= (UNITS_PER_WORD
- 1) - (byte
% UNITS_PER_WORD
);
7539 offset
+= byte
% UNITS_PER_WORD
;
7542 offset
= BYTES_BIG_ENDIAN
? (total_bytes
- 1) - byte
: byte
;
7543 ptr
[offset
] = value
;
7549 /* Subroutine of native_encode_expr. Encode the REAL_CST
7550 specified by EXPR into the buffer PTR of length LEN bytes.
7551 Return the number of bytes placed in the buffer, or zero
7555 native_encode_real (const_tree expr
, unsigned char *ptr
, int len
)
7557 tree type
= TREE_TYPE (expr
);
7558 int total_bytes
= GET_MODE_SIZE (TYPE_MODE (type
));
7559 int byte
, offset
, word
, words
, bitpos
;
7560 unsigned char value
;
7562 /* There are always 32 bits in each long, no matter the size of
7563 the hosts long. We handle floating point representations with
7567 if (total_bytes
> len
)
7569 words
= 32 / UNITS_PER_WORD
;
7571 real_to_target (tmp
, TREE_REAL_CST_PTR (expr
), TYPE_MODE (type
));
7573 for (bitpos
= 0; bitpos
< total_bytes
* BITS_PER_UNIT
;
7574 bitpos
+= BITS_PER_UNIT
)
7576 byte
= (bitpos
/ BITS_PER_UNIT
) & 3;
7577 value
= (unsigned char) (tmp
[bitpos
/ 32] >> (bitpos
& 31));
7579 if (UNITS_PER_WORD
< 4)
7581 word
= byte
/ UNITS_PER_WORD
;
7582 if (WORDS_BIG_ENDIAN
)
7583 word
= (words
- 1) - word
;
7584 offset
= word
* UNITS_PER_WORD
;
7585 if (BYTES_BIG_ENDIAN
)
7586 offset
+= (UNITS_PER_WORD
- 1) - (byte
% UNITS_PER_WORD
);
7588 offset
+= byte
% UNITS_PER_WORD
;
7591 offset
= BYTES_BIG_ENDIAN
? 3 - byte
: byte
;
7592 ptr
[offset
+ ((bitpos
/ BITS_PER_UNIT
) & ~3)] = value
;
7597 /* Subroutine of native_encode_expr. Encode the COMPLEX_CST
7598 specified by EXPR into the buffer PTR of length LEN bytes.
7599 Return the number of bytes placed in the buffer, or zero
7603 native_encode_complex (const_tree expr
, unsigned char *ptr
, int len
)
7608 part
= TREE_REALPART (expr
);
7609 rsize
= native_encode_expr (part
, ptr
, len
);
7612 part
= TREE_IMAGPART (expr
);
7613 isize
= native_encode_expr (part
, ptr
+rsize
, len
-rsize
);
7616 return rsize
+ isize
;
7620 /* Subroutine of native_encode_expr. Encode the VECTOR_CST
7621 specified by EXPR into the buffer PTR of length LEN bytes.
7622 Return the number of bytes placed in the buffer, or zero
7626 native_encode_vector (const_tree expr
, unsigned char *ptr
, int len
)
7628 int i
, size
, offset
, count
;
7629 tree itype
, elem
, elements
;
7632 elements
= TREE_VECTOR_CST_ELTS (expr
);
7633 count
= TYPE_VECTOR_SUBPARTS (TREE_TYPE (expr
));
7634 itype
= TREE_TYPE (TREE_TYPE (expr
));
7635 size
= GET_MODE_SIZE (TYPE_MODE (itype
));
7636 for (i
= 0; i
< count
; i
++)
7640 elem
= TREE_VALUE (elements
);
7641 elements
= TREE_CHAIN (elements
);
7648 if (native_encode_expr (elem
, ptr
+offset
, len
-offset
) != size
)
7653 if (offset
+ size
> len
)
7655 memset (ptr
+offset
, 0, size
);
7663 /* Subroutine of fold_view_convert_expr. Encode the INTEGER_CST,
7664 REAL_CST, COMPLEX_CST or VECTOR_CST specified by EXPR into the
7665 buffer PTR of length LEN bytes. Return the number of bytes
7666 placed in the buffer, or zero upon failure. */
7669 native_encode_expr (const_tree expr
, unsigned char *ptr
, int len
)
7671 switch (TREE_CODE (expr
))
7674 return native_encode_int (expr
, ptr
, len
);
7677 return native_encode_real (expr
, ptr
, len
);
7680 return native_encode_complex (expr
, ptr
, len
);
7683 return native_encode_vector (expr
, ptr
, len
);
7691 /* Subroutine of native_interpret_expr. Interpret the contents of
7692 the buffer PTR of length LEN as an INTEGER_CST of type TYPE.
7693 If the buffer cannot be interpreted, return NULL_TREE. */
7696 native_interpret_int (tree type
, const unsigned char *ptr
, int len
)
7698 int total_bytes
= GET_MODE_SIZE (TYPE_MODE (type
));
7699 int byte
, offset
, word
, words
;
7700 unsigned char value
;
7701 unsigned int HOST_WIDE_INT lo
= 0;
7702 HOST_WIDE_INT hi
= 0;
7704 if (total_bytes
> len
)
7706 if (total_bytes
* BITS_PER_UNIT
> 2 * HOST_BITS_PER_WIDE_INT
)
7708 words
= total_bytes
/ UNITS_PER_WORD
;
7710 for (byte
= 0; byte
< total_bytes
; byte
++)
7712 int bitpos
= byte
* BITS_PER_UNIT
;
7713 if (total_bytes
> UNITS_PER_WORD
)
7715 word
= byte
/ UNITS_PER_WORD
;
7716 if (WORDS_BIG_ENDIAN
)
7717 word
= (words
- 1) - word
;
7718 offset
= word
* UNITS_PER_WORD
;
7719 if (BYTES_BIG_ENDIAN
)
7720 offset
+= (UNITS_PER_WORD
- 1) - (byte
% UNITS_PER_WORD
);
7722 offset
+= byte
% UNITS_PER_WORD
;
7725 offset
= BYTES_BIG_ENDIAN
? (total_bytes
- 1) - byte
: byte
;
7726 value
= ptr
[offset
];
7728 if (bitpos
< HOST_BITS_PER_WIDE_INT
)
7729 lo
|= (unsigned HOST_WIDE_INT
) value
<< bitpos
;
7731 hi
|= (unsigned HOST_WIDE_INT
) value
7732 << (bitpos
- HOST_BITS_PER_WIDE_INT
);
7735 return build_int_cst_wide_type (type
, lo
, hi
);
7739 /* Subroutine of native_interpret_expr. Interpret the contents of
7740 the buffer PTR of length LEN as a REAL_CST of type TYPE.
7741 If the buffer cannot be interpreted, return NULL_TREE. */
7744 native_interpret_real (tree type
, const unsigned char *ptr
, int len
)
7746 enum machine_mode mode
= TYPE_MODE (type
);
7747 int total_bytes
= GET_MODE_SIZE (mode
);
7748 int byte
, offset
, word
, words
, bitpos
;
7749 unsigned char value
;
7750 /* There are always 32 bits in each long, no matter the size of
7751 the hosts long. We handle floating point representations with
7756 total_bytes
= GET_MODE_SIZE (TYPE_MODE (type
));
7757 if (total_bytes
> len
|| total_bytes
> 24)
7759 words
= 32 / UNITS_PER_WORD
;
7761 memset (tmp
, 0, sizeof (tmp
));
7762 for (bitpos
= 0; bitpos
< total_bytes
* BITS_PER_UNIT
;
7763 bitpos
+= BITS_PER_UNIT
)
7765 byte
= (bitpos
/ BITS_PER_UNIT
) & 3;
7766 if (UNITS_PER_WORD
< 4)
7768 word
= byte
/ UNITS_PER_WORD
;
7769 if (WORDS_BIG_ENDIAN
)
7770 word
= (words
- 1) - word
;
7771 offset
= word
* UNITS_PER_WORD
;
7772 if (BYTES_BIG_ENDIAN
)
7773 offset
+= (UNITS_PER_WORD
- 1) - (byte
% UNITS_PER_WORD
);
7775 offset
+= byte
% UNITS_PER_WORD
;
7778 offset
= BYTES_BIG_ENDIAN
? 3 - byte
: byte
;
7779 value
= ptr
[offset
+ ((bitpos
/ BITS_PER_UNIT
) & ~3)];
7781 tmp
[bitpos
/ 32] |= (unsigned long)value
<< (bitpos
& 31);
7784 real_from_target (&r
, tmp
, mode
);
7785 return build_real (type
, r
);
7789 /* Subroutine of native_interpret_expr. Interpret the contents of
7790 the buffer PTR of length LEN as a COMPLEX_CST of type TYPE.
7791 If the buffer cannot be interpreted, return NULL_TREE. */
7794 native_interpret_complex (tree type
, const unsigned char *ptr
, int len
)
7796 tree etype
, rpart
, ipart
;
7799 etype
= TREE_TYPE (type
);
7800 size
= GET_MODE_SIZE (TYPE_MODE (etype
));
7803 rpart
= native_interpret_expr (etype
, ptr
, size
);
7806 ipart
= native_interpret_expr (etype
, ptr
+size
, size
);
7809 return build_complex (type
, rpart
, ipart
);
7813 /* Subroutine of native_interpret_expr. Interpret the contents of
7814 the buffer PTR of length LEN as a VECTOR_CST of type TYPE.
7815 If the buffer cannot be interpreted, return NULL_TREE. */
7818 native_interpret_vector (tree type
, const unsigned char *ptr
, int len
)
7820 tree etype
, elem
, elements
;
7823 etype
= TREE_TYPE (type
);
7824 size
= GET_MODE_SIZE (TYPE_MODE (etype
));
7825 count
= TYPE_VECTOR_SUBPARTS (type
);
7826 if (size
* count
> len
)
7829 elements
= NULL_TREE
;
7830 for (i
= count
- 1; i
>= 0; i
--)
7832 elem
= native_interpret_expr (etype
, ptr
+(i
*size
), size
);
7835 elements
= tree_cons (NULL_TREE
, elem
, elements
);
7837 return build_vector (type
, elements
);
7841 /* Subroutine of fold_view_convert_expr. Interpret the contents of
7842 the buffer PTR of length LEN as a constant of type TYPE. For
7843 INTEGRAL_TYPE_P we return an INTEGER_CST, for SCALAR_FLOAT_TYPE_P
7844 we return a REAL_CST, etc... If the buffer cannot be interpreted,
7845 return NULL_TREE. */
7848 native_interpret_expr (tree type
, const unsigned char *ptr
, int len
)
7850 switch (TREE_CODE (type
))
7855 return native_interpret_int (type
, ptr
, len
);
7858 return native_interpret_real (type
, ptr
, len
);
7861 return native_interpret_complex (type
, ptr
, len
);
7864 return native_interpret_vector (type
, ptr
, len
);
7872 /* Fold a VIEW_CONVERT_EXPR of a constant expression EXPR to type
7873 TYPE at compile-time. If we're unable to perform the conversion
7874 return NULL_TREE. */
7877 fold_view_convert_expr (tree type
, tree expr
)
7879 /* We support up to 512-bit values (for V8DFmode). */
7880 unsigned char buffer
[64];
7883 /* Check that the host and target are sane. */
7884 if (CHAR_BIT
!= 8 || BITS_PER_UNIT
!= 8)
7887 len
= native_encode_expr (expr
, buffer
, sizeof (buffer
));
7891 return native_interpret_expr (type
, buffer
, len
);
7894 /* Build an expression for the address of T. Folds away INDIRECT_REF
7895 to avoid confusing the gimplify process. When IN_FOLD is true
7896 avoid modifications of T. */
7899 build_fold_addr_expr_with_type_1 (tree t
, tree ptrtype
, bool in_fold
)
7901 /* The size of the object is not relevant when talking about its address. */
7902 if (TREE_CODE (t
) == WITH_SIZE_EXPR
)
7903 t
= TREE_OPERAND (t
, 0);
7905 /* Note: doesn't apply to ALIGN_INDIRECT_REF */
7906 if (TREE_CODE (t
) == INDIRECT_REF
7907 || TREE_CODE (t
) == MISALIGNED_INDIRECT_REF
)
7909 t
= TREE_OPERAND (t
, 0);
7911 if (TREE_TYPE (t
) != ptrtype
)
7912 t
= build1 (NOP_EXPR
, ptrtype
, t
);
7918 while (handled_component_p (base
))
7919 base
= TREE_OPERAND (base
, 0);
7922 TREE_ADDRESSABLE (base
) = 1;
7924 t
= build1 (ADDR_EXPR
, ptrtype
, t
);
7927 t
= build1 (ADDR_EXPR
, ptrtype
, t
);
7932 /* Build an expression for the address of T with type PTRTYPE. This
7933 function modifies the input parameter 'T' by sometimes setting the
7934 TREE_ADDRESSABLE flag. */
7937 build_fold_addr_expr_with_type (tree t
, tree ptrtype
)
7939 return build_fold_addr_expr_with_type_1 (t
, ptrtype
, false);
7942 /* Build an expression for the address of T. This function modifies
7943 the input parameter 'T' by sometimes setting the TREE_ADDRESSABLE
7944 flag. When called from fold functions, use fold_addr_expr instead. */
7947 build_fold_addr_expr (tree t
)
7949 return build_fold_addr_expr_with_type_1 (t
,
7950 build_pointer_type (TREE_TYPE (t
)),
7954 /* Same as build_fold_addr_expr, builds an expression for the address
7955 of T, but avoids touching the input node 't'. Fold functions
7956 should use this version. */
7959 fold_addr_expr (tree t
)
7961 tree ptrtype
= build_pointer_type (TREE_TYPE (t
));
7963 return build_fold_addr_expr_with_type_1 (t
, ptrtype
, true);
7966 /* Fold a unary expression of code CODE and type TYPE with operand
7967 OP0. Return the folded expression if folding is successful.
7968 Otherwise, return NULL_TREE. */
7971 fold_unary (enum tree_code code
, tree type
, tree op0
)
7975 enum tree_code_class kind
= TREE_CODE_CLASS (code
);
7977 gcc_assert (IS_EXPR_CODE_CLASS (kind
)
7978 && TREE_CODE_LENGTH (code
) == 1);
7983 if (code
== NOP_EXPR
|| code
== CONVERT_EXPR
7984 || code
== FLOAT_EXPR
|| code
== ABS_EXPR
)
7986 /* Don't use STRIP_NOPS, because signedness of argument type
7988 STRIP_SIGN_NOPS (arg0
);
7992 /* Strip any conversions that don't change the mode. This
7993 is safe for every expression, except for a comparison
7994 expression because its signedness is derived from its
7997 Note that this is done as an internal manipulation within
7998 the constant folder, in order to find the simplest
7999 representation of the arguments so that their form can be
8000 studied. In any cases, the appropriate type conversions
8001 should be put back in the tree that will get out of the
8007 if (TREE_CODE_CLASS (code
) == tcc_unary
)
8009 if (TREE_CODE (arg0
) == COMPOUND_EXPR
)
8010 return build2 (COMPOUND_EXPR
, type
, TREE_OPERAND (arg0
, 0),
8011 fold_build1 (code
, type
, TREE_OPERAND (arg0
, 1)));
8012 else if (TREE_CODE (arg0
) == COND_EXPR
)
8014 tree arg01
= TREE_OPERAND (arg0
, 1);
8015 tree arg02
= TREE_OPERAND (arg0
, 2);
8016 if (! VOID_TYPE_P (TREE_TYPE (arg01
)))
8017 arg01
= fold_build1 (code
, type
, arg01
);
8018 if (! VOID_TYPE_P (TREE_TYPE (arg02
)))
8019 arg02
= fold_build1 (code
, type
, arg02
);
8020 tem
= fold_build3 (COND_EXPR
, type
, TREE_OPERAND (arg0
, 0),
8023 /* If this was a conversion, and all we did was to move into
8024 inside the COND_EXPR, bring it back out. But leave it if
8025 it is a conversion from integer to integer and the
8026 result precision is no wider than a word since such a
8027 conversion is cheap and may be optimized away by combine,
8028 while it couldn't if it were outside the COND_EXPR. Then return
8029 so we don't get into an infinite recursion loop taking the
8030 conversion out and then back in. */
8032 if ((code
== NOP_EXPR
|| code
== CONVERT_EXPR
8033 || code
== NON_LVALUE_EXPR
)
8034 && TREE_CODE (tem
) == COND_EXPR
8035 && TREE_CODE (TREE_OPERAND (tem
, 1)) == code
8036 && TREE_CODE (TREE_OPERAND (tem
, 2)) == code
8037 && ! VOID_TYPE_P (TREE_OPERAND (tem
, 1))
8038 && ! VOID_TYPE_P (TREE_OPERAND (tem
, 2))
8039 && (TREE_TYPE (TREE_OPERAND (TREE_OPERAND (tem
, 1), 0))
8040 == TREE_TYPE (TREE_OPERAND (TREE_OPERAND (tem
, 2), 0)))
8041 && (! (INTEGRAL_TYPE_P (TREE_TYPE (tem
))
8043 (TREE_TYPE (TREE_OPERAND (TREE_OPERAND (tem
, 1), 0))))
8044 && TYPE_PRECISION (TREE_TYPE (tem
)) <= BITS_PER_WORD
)
8045 || flag_syntax_only
))
8046 tem
= build1 (code
, type
,
8048 TREE_TYPE (TREE_OPERAND
8049 (TREE_OPERAND (tem
, 1), 0)),
8050 TREE_OPERAND (tem
, 0),
8051 TREE_OPERAND (TREE_OPERAND (tem
, 1), 0),
8052 TREE_OPERAND (TREE_OPERAND (tem
, 2), 0)));
8055 else if (COMPARISON_CLASS_P (arg0
))
8057 if (TREE_CODE (type
) == BOOLEAN_TYPE
)
8059 arg0
= copy_node (arg0
);
8060 TREE_TYPE (arg0
) = type
;
8063 else if (TREE_CODE (type
) != INTEGER_TYPE
)
8064 return fold_build3 (COND_EXPR
, type
, arg0
,
8065 fold_build1 (code
, type
,
8067 fold_build1 (code
, type
,
8068 integer_zero_node
));
8077 case FIX_TRUNC_EXPR
:
8078 if (TREE_TYPE (op0
) == type
)
8081 /* If we have (type) (a CMP b) and type is an integral type, return
8082 new expression involving the new type. */
8083 if (COMPARISON_CLASS_P (op0
) && INTEGRAL_TYPE_P (type
))
8084 return fold_build2 (TREE_CODE (op0
), type
, TREE_OPERAND (op0
, 0),
8085 TREE_OPERAND (op0
, 1));
8087 /* Handle cases of two conversions in a row. */
8088 if (TREE_CODE (op0
) == NOP_EXPR
8089 || TREE_CODE (op0
) == CONVERT_EXPR
)
8091 tree inside_type
= TREE_TYPE (TREE_OPERAND (op0
, 0));
8092 tree inter_type
= TREE_TYPE (op0
);
8093 int inside_int
= INTEGRAL_TYPE_P (inside_type
);
8094 int inside_ptr
= POINTER_TYPE_P (inside_type
);
8095 int inside_float
= FLOAT_TYPE_P (inside_type
);
8096 int inside_vec
= TREE_CODE (inside_type
) == VECTOR_TYPE
;
8097 unsigned int inside_prec
= TYPE_PRECISION (inside_type
);
8098 int inside_unsignedp
= TYPE_UNSIGNED (inside_type
);
8099 int inter_int
= INTEGRAL_TYPE_P (inter_type
);
8100 int inter_ptr
= POINTER_TYPE_P (inter_type
);
8101 int inter_float
= FLOAT_TYPE_P (inter_type
);
8102 int inter_vec
= TREE_CODE (inter_type
) == VECTOR_TYPE
;
8103 unsigned int inter_prec
= TYPE_PRECISION (inter_type
);
8104 int inter_unsignedp
= TYPE_UNSIGNED (inter_type
);
8105 int final_int
= INTEGRAL_TYPE_P (type
);
8106 int final_ptr
= POINTER_TYPE_P (type
);
8107 int final_float
= FLOAT_TYPE_P (type
);
8108 int final_vec
= TREE_CODE (type
) == VECTOR_TYPE
;
8109 unsigned int final_prec
= TYPE_PRECISION (type
);
8110 int final_unsignedp
= TYPE_UNSIGNED (type
);
8112 /* In addition to the cases of two conversions in a row
8113 handled below, if we are converting something to its own
8114 type via an object of identical or wider precision, neither
8115 conversion is needed. */
8116 if (TYPE_MAIN_VARIANT (inside_type
) == TYPE_MAIN_VARIANT (type
)
8117 && (((inter_int
|| inter_ptr
) && final_int
)
8118 || (inter_float
&& final_float
))
8119 && inter_prec
>= final_prec
)
8120 return fold_build1 (code
, type
, TREE_OPERAND (op0
, 0));
8122 /* Likewise, if the intermediate and final types are either both
8123 float or both integer, we don't need the middle conversion if
8124 it is wider than the final type and doesn't change the signedness
8125 (for integers). Avoid this if the final type is a pointer
8126 since then we sometimes need the inner conversion. Likewise if
8127 the outer has a precision not equal to the size of its mode. */
8128 if ((((inter_int
|| inter_ptr
) && (inside_int
|| inside_ptr
))
8129 || (inter_float
&& inside_float
)
8130 || (inter_vec
&& inside_vec
))
8131 && inter_prec
>= inside_prec
8132 && (inter_float
|| inter_vec
8133 || inter_unsignedp
== inside_unsignedp
)
8134 && ! (final_prec
!= GET_MODE_BITSIZE (TYPE_MODE (type
))
8135 && TYPE_MODE (type
) == TYPE_MODE (inter_type
))
8137 && (! final_vec
|| inter_prec
== inside_prec
))
8138 return fold_build1 (code
, type
, TREE_OPERAND (op0
, 0));
8140 /* If we have a sign-extension of a zero-extended value, we can
8141 replace that by a single zero-extension. */
8142 if (inside_int
&& inter_int
&& final_int
8143 && inside_prec
< inter_prec
&& inter_prec
< final_prec
8144 && inside_unsignedp
&& !inter_unsignedp
)
8145 return fold_build1 (code
, type
, TREE_OPERAND (op0
, 0));
8147 /* Two conversions in a row are not needed unless:
8148 - some conversion is floating-point (overstrict for now), or
8149 - some conversion is a vector (overstrict for now), or
8150 - the intermediate type is narrower than both initial and
8152 - the intermediate type and innermost type differ in signedness,
8153 and the outermost type is wider than the intermediate, or
8154 - the initial type is a pointer type and the precisions of the
8155 intermediate and final types differ, or
8156 - the final type is a pointer type and the precisions of the
8157 initial and intermediate types differ.
8158 - the final type is a pointer type and the initial type not
8159 - the initial type is a pointer to an array and the final type
8161 if (! inside_float
&& ! inter_float
&& ! final_float
8162 && ! inside_vec
&& ! inter_vec
&& ! final_vec
8163 && (inter_prec
>= inside_prec
|| inter_prec
>= final_prec
)
8164 && ! (inside_int
&& inter_int
8165 && inter_unsignedp
!= inside_unsignedp
8166 && inter_prec
< final_prec
)
8167 && ((inter_unsignedp
&& inter_prec
> inside_prec
)
8168 == (final_unsignedp
&& final_prec
> inter_prec
))
8169 && ! (inside_ptr
&& inter_prec
!= final_prec
)
8170 && ! (final_ptr
&& inside_prec
!= inter_prec
)
8171 && ! (final_prec
!= GET_MODE_BITSIZE (TYPE_MODE (type
))
8172 && TYPE_MODE (type
) == TYPE_MODE (inter_type
))
8173 && final_ptr
== inside_ptr
8175 && TREE_CODE (TREE_TYPE (inside_type
)) == ARRAY_TYPE
8176 && TREE_CODE (TREE_TYPE (type
)) != ARRAY_TYPE
))
8177 return fold_build1 (code
, type
, TREE_OPERAND (op0
, 0));
8180 /* Handle (T *)&A.B.C for A being of type T and B and C
8181 living at offset zero. This occurs frequently in
8182 C++ upcasting and then accessing the base. */
8183 if (TREE_CODE (op0
) == ADDR_EXPR
8184 && POINTER_TYPE_P (type
)
8185 && handled_component_p (TREE_OPERAND (op0
, 0)))
8187 HOST_WIDE_INT bitsize
, bitpos
;
8189 enum machine_mode mode
;
8190 int unsignedp
, volatilep
;
8191 tree base
= TREE_OPERAND (op0
, 0);
8192 base
= get_inner_reference (base
, &bitsize
, &bitpos
, &offset
,
8193 &mode
, &unsignedp
, &volatilep
, false);
8194 /* If the reference was to a (constant) zero offset, we can use
8195 the address of the base if it has the same base type
8196 as the result type. */
8197 if (! offset
&& bitpos
== 0
8198 && TYPE_MAIN_VARIANT (TREE_TYPE (type
))
8199 == TYPE_MAIN_VARIANT (TREE_TYPE (base
)))
8200 return fold_convert (type
, fold_addr_expr (base
));
8203 if ((TREE_CODE (op0
) == MODIFY_EXPR
8204 || TREE_CODE (op0
) == GIMPLE_MODIFY_STMT
)
8205 && TREE_CONSTANT (GENERIC_TREE_OPERAND (op0
, 1))
8206 /* Detect assigning a bitfield. */
8207 && !(TREE_CODE (GENERIC_TREE_OPERAND (op0
, 0)) == COMPONENT_REF
8209 (TREE_OPERAND (GENERIC_TREE_OPERAND (op0
, 0), 1))))
8211 /* Don't leave an assignment inside a conversion
8212 unless assigning a bitfield. */
8213 tem
= fold_build1 (code
, type
, GENERIC_TREE_OPERAND (op0
, 1));
8214 /* First do the assignment, then return converted constant. */
8215 tem
= build2 (COMPOUND_EXPR
, TREE_TYPE (tem
), op0
, tem
);
8216 TREE_NO_WARNING (tem
) = 1;
8217 TREE_USED (tem
) = 1;
8221 /* Convert (T)(x & c) into (T)x & (T)c, if c is an integer
8222 constants (if x has signed type, the sign bit cannot be set
8223 in c). This folds extension into the BIT_AND_EXPR. */
8224 if (INTEGRAL_TYPE_P (type
)
8225 && TREE_CODE (type
) != BOOLEAN_TYPE
8226 && TREE_CODE (op0
) == BIT_AND_EXPR
8227 && TREE_CODE (TREE_OPERAND (op0
, 1)) == INTEGER_CST
)
8230 tree and0
= TREE_OPERAND (and, 0), and1
= TREE_OPERAND (and, 1);
8233 if (TYPE_UNSIGNED (TREE_TYPE (and))
8234 || (TYPE_PRECISION (type
)
8235 <= TYPE_PRECISION (TREE_TYPE (and))))
8237 else if (TYPE_PRECISION (TREE_TYPE (and1
))
8238 <= HOST_BITS_PER_WIDE_INT
8239 && host_integerp (and1
, 1))
8241 unsigned HOST_WIDE_INT cst
;
8243 cst
= tree_low_cst (and1
, 1);
8244 cst
&= (HOST_WIDE_INT
) -1
8245 << (TYPE_PRECISION (TREE_TYPE (and1
)) - 1);
8246 change
= (cst
== 0);
8247 #ifdef LOAD_EXTEND_OP
8249 && !flag_syntax_only
8250 && (LOAD_EXTEND_OP (TYPE_MODE (TREE_TYPE (and0
)))
8253 tree uns
= unsigned_type_for (TREE_TYPE (and0
));
8254 and0
= fold_convert (uns
, and0
);
8255 and1
= fold_convert (uns
, and1
);
8261 tem
= force_fit_type_double (type
, TREE_INT_CST_LOW (and1
),
8262 TREE_INT_CST_HIGH (and1
), 0,
8263 TREE_OVERFLOW (and1
));
8264 return fold_build2 (BIT_AND_EXPR
, type
,
8265 fold_convert (type
, and0
), tem
);
8269 /* Convert (T1)(X p+ Y) into ((T1)X p+ Y), for pointer type,
8270 when one of the new casts will fold away. Conservatively we assume
8271 that this happens when X or Y is NOP_EXPR or Y is INTEGER_CST. */
8272 if (POINTER_TYPE_P (type
)
8273 && TREE_CODE (arg0
) == POINTER_PLUS_EXPR
8274 && (TREE_CODE (TREE_OPERAND (arg0
, 1)) == INTEGER_CST
8275 || TREE_CODE (TREE_OPERAND (arg0
, 0)) == NOP_EXPR
8276 || TREE_CODE (TREE_OPERAND (arg0
, 1)) == NOP_EXPR
))
8278 tree arg00
= TREE_OPERAND (arg0
, 0);
8279 tree arg01
= TREE_OPERAND (arg0
, 1);
8281 return fold_build2 (TREE_CODE (arg0
), type
, fold_convert (type
, arg00
),
8282 fold_convert (sizetype
, arg01
));
8285 /* Convert (T1)(~(T2)X) into ~(T1)X if T1 and T2 are integral types
8286 of the same precision, and X is an integer type not narrower than
8287 types T1 or T2, i.e. the cast (T2)X isn't an extension. */
8288 if (INTEGRAL_TYPE_P (type
)
8289 && TREE_CODE (op0
) == BIT_NOT_EXPR
8290 && INTEGRAL_TYPE_P (TREE_TYPE (op0
))
8291 && (TREE_CODE (TREE_OPERAND (op0
, 0)) == NOP_EXPR
8292 || TREE_CODE (TREE_OPERAND (op0
, 0)) == CONVERT_EXPR
)
8293 && TYPE_PRECISION (type
) == TYPE_PRECISION (TREE_TYPE (op0
)))
8295 tem
= TREE_OPERAND (TREE_OPERAND (op0
, 0), 0);
8296 if (INTEGRAL_TYPE_P (TREE_TYPE (tem
))
8297 && TYPE_PRECISION (type
) <= TYPE_PRECISION (TREE_TYPE (tem
)))
8298 return fold_build1 (BIT_NOT_EXPR
, type
, fold_convert (type
, tem
));
8301 tem
= fold_convert_const (code
, type
, op0
);
8302 return tem
? tem
: NULL_TREE
;
8304 case FIXED_CONVERT_EXPR
:
8305 tem
= fold_convert_const (code
, type
, arg0
);
8306 return tem
? tem
: NULL_TREE
;
8308 case VIEW_CONVERT_EXPR
:
8309 if (TREE_TYPE (op0
) == type
)
8311 if (TREE_CODE (op0
) == VIEW_CONVERT_EXPR
)
8312 return fold_build1 (VIEW_CONVERT_EXPR
, type
, TREE_OPERAND (op0
, 0));
8313 return fold_view_convert_expr (type
, op0
);
8316 tem
= fold_negate_expr (arg0
);
8318 return fold_convert (type
, tem
);
8322 if (TREE_CODE (arg0
) == INTEGER_CST
|| TREE_CODE (arg0
) == REAL_CST
)
8323 return fold_abs_const (arg0
, type
);
8324 else if (TREE_CODE (arg0
) == NEGATE_EXPR
)
8325 return fold_build1 (ABS_EXPR
, type
, TREE_OPERAND (arg0
, 0));
8326 /* Convert fabs((double)float) into (double)fabsf(float). */
8327 else if (TREE_CODE (arg0
) == NOP_EXPR
8328 && TREE_CODE (type
) == REAL_TYPE
)
8330 tree targ0
= strip_float_extensions (arg0
);
8332 return fold_convert (type
, fold_build1 (ABS_EXPR
,
8336 /* ABS_EXPR<ABS_EXPR<x>> = ABS_EXPR<x> even if flag_wrapv is on. */
8337 else if (TREE_CODE (arg0
) == ABS_EXPR
)
8339 else if (tree_expr_nonnegative_p (arg0
))
8342 /* Strip sign ops from argument. */
8343 if (TREE_CODE (type
) == REAL_TYPE
)
8345 tem
= fold_strip_sign_ops (arg0
);
8347 return fold_build1 (ABS_EXPR
, type
, fold_convert (type
, tem
));
8352 if (TREE_CODE (TREE_TYPE (arg0
)) != COMPLEX_TYPE
)
8353 return fold_convert (type
, arg0
);
8354 if (TREE_CODE (arg0
) == COMPLEX_EXPR
)
8356 tree itype
= TREE_TYPE (type
);
8357 tree rpart
= fold_convert (itype
, TREE_OPERAND (arg0
, 0));
8358 tree ipart
= fold_convert (itype
, TREE_OPERAND (arg0
, 1));
8359 return fold_build2 (COMPLEX_EXPR
, type
, rpart
, negate_expr (ipart
));
8361 if (TREE_CODE (arg0
) == COMPLEX_CST
)
8363 tree itype
= TREE_TYPE (type
);
8364 tree rpart
= fold_convert (itype
, TREE_REALPART (arg0
));
8365 tree ipart
= fold_convert (itype
, TREE_IMAGPART (arg0
));
8366 return build_complex (type
, rpart
, negate_expr (ipart
));
8368 if (TREE_CODE (arg0
) == CONJ_EXPR
)
8369 return fold_convert (type
, TREE_OPERAND (arg0
, 0));
8373 if (TREE_CODE (arg0
) == INTEGER_CST
)
8374 return fold_not_const (arg0
, type
);
8375 else if (TREE_CODE (arg0
) == BIT_NOT_EXPR
)
8376 return TREE_OPERAND (arg0
, 0);
8377 /* Convert ~ (-A) to A - 1. */
8378 else if (INTEGRAL_TYPE_P (type
) && TREE_CODE (arg0
) == NEGATE_EXPR
)
8379 return fold_build2 (MINUS_EXPR
, type
, TREE_OPERAND (arg0
, 0),
8380 build_int_cst (type
, 1));
8381 /* Convert ~ (A - 1) or ~ (A + -1) to -A. */
8382 else if (INTEGRAL_TYPE_P (type
)
8383 && ((TREE_CODE (arg0
) == MINUS_EXPR
8384 && integer_onep (TREE_OPERAND (arg0
, 1)))
8385 || (TREE_CODE (arg0
) == PLUS_EXPR
8386 && integer_all_onesp (TREE_OPERAND (arg0
, 1)))))
8387 return fold_build1 (NEGATE_EXPR
, type
, TREE_OPERAND (arg0
, 0));
8388 /* Convert ~(X ^ Y) to ~X ^ Y or X ^ ~Y if ~X or ~Y simplify. */
8389 else if (TREE_CODE (arg0
) == BIT_XOR_EXPR
8390 && (tem
= fold_unary (BIT_NOT_EXPR
, type
,
8392 TREE_OPERAND (arg0
, 0)))))
8393 return fold_build2 (BIT_XOR_EXPR
, type
, tem
,
8394 fold_convert (type
, TREE_OPERAND (arg0
, 1)));
8395 else if (TREE_CODE (arg0
) == BIT_XOR_EXPR
8396 && (tem
= fold_unary (BIT_NOT_EXPR
, type
,
8398 TREE_OPERAND (arg0
, 1)))))
8399 return fold_build2 (BIT_XOR_EXPR
, type
,
8400 fold_convert (type
, TREE_OPERAND (arg0
, 0)), tem
);
8401 /* Perform BIT_NOT_EXPR on each element individually. */
8402 else if (TREE_CODE (arg0
) == VECTOR_CST
)
8404 tree elements
= TREE_VECTOR_CST_ELTS (arg0
), elem
, list
= NULL_TREE
;
8405 int count
= TYPE_VECTOR_SUBPARTS (type
), i
;
8407 for (i
= 0; i
< count
; i
++)
8411 elem
= TREE_VALUE (elements
);
8412 elem
= fold_unary (BIT_NOT_EXPR
, TREE_TYPE (type
), elem
);
8413 if (elem
== NULL_TREE
)
8415 elements
= TREE_CHAIN (elements
);
8418 elem
= build_int_cst (TREE_TYPE (type
), -1);
8419 list
= tree_cons (NULL_TREE
, elem
, list
);
8422 return build_vector (type
, nreverse (list
));
8427 case TRUTH_NOT_EXPR
:
8428 /* The argument to invert_truthvalue must have Boolean type. */
8429 if (TREE_CODE (TREE_TYPE (arg0
)) != BOOLEAN_TYPE
)
8430 arg0
= fold_convert (boolean_type_node
, arg0
);
8432 /* Note that the operand of this must be an int
8433 and its values must be 0 or 1.
8434 ("true" is a fixed value perhaps depending on the language,
8435 but we don't handle values other than 1 correctly yet.) */
8436 tem
= fold_truth_not_expr (arg0
);
8439 return fold_convert (type
, tem
);
8442 if (TREE_CODE (TREE_TYPE (arg0
)) != COMPLEX_TYPE
)
8443 return fold_convert (type
, arg0
);
8444 if (TREE_CODE (arg0
) == COMPLEX_EXPR
)
8445 return omit_one_operand (type
, TREE_OPERAND (arg0
, 0),
8446 TREE_OPERAND (arg0
, 1));
8447 if (TREE_CODE (arg0
) == COMPLEX_CST
)
8448 return fold_convert (type
, TREE_REALPART (arg0
));
8449 if (TREE_CODE (arg0
) == PLUS_EXPR
|| TREE_CODE (arg0
) == MINUS_EXPR
)
8451 tree itype
= TREE_TYPE (TREE_TYPE (arg0
));
8452 tem
= fold_build2 (TREE_CODE (arg0
), itype
,
8453 fold_build1 (REALPART_EXPR
, itype
,
8454 TREE_OPERAND (arg0
, 0)),
8455 fold_build1 (REALPART_EXPR
, itype
,
8456 TREE_OPERAND (arg0
, 1)));
8457 return fold_convert (type
, tem
);
8459 if (TREE_CODE (arg0
) == CONJ_EXPR
)
8461 tree itype
= TREE_TYPE (TREE_TYPE (arg0
));
8462 tem
= fold_build1 (REALPART_EXPR
, itype
, TREE_OPERAND (arg0
, 0));
8463 return fold_convert (type
, tem
);
8465 if (TREE_CODE (arg0
) == CALL_EXPR
)
8467 tree fn
= get_callee_fndecl (arg0
);
8468 if (fn
&& DECL_BUILT_IN_CLASS (fn
) == BUILT_IN_NORMAL
)
8469 switch (DECL_FUNCTION_CODE (fn
))
8471 CASE_FLT_FN (BUILT_IN_CEXPI
):
8472 fn
= mathfn_built_in (type
, BUILT_IN_COS
);
8474 return build_call_expr (fn
, 1, CALL_EXPR_ARG (arg0
, 0));
8484 if (TREE_CODE (TREE_TYPE (arg0
)) != COMPLEX_TYPE
)
8485 return fold_convert (type
, integer_zero_node
);
8486 if (TREE_CODE (arg0
) == COMPLEX_EXPR
)
8487 return omit_one_operand (type
, TREE_OPERAND (arg0
, 1),
8488 TREE_OPERAND (arg0
, 0));
8489 if (TREE_CODE (arg0
) == COMPLEX_CST
)
8490 return fold_convert (type
, TREE_IMAGPART (arg0
));
8491 if (TREE_CODE (arg0
) == PLUS_EXPR
|| TREE_CODE (arg0
) == MINUS_EXPR
)
8493 tree itype
= TREE_TYPE (TREE_TYPE (arg0
));
8494 tem
= fold_build2 (TREE_CODE (arg0
), itype
,
8495 fold_build1 (IMAGPART_EXPR
, itype
,
8496 TREE_OPERAND (arg0
, 0)),
8497 fold_build1 (IMAGPART_EXPR
, itype
,
8498 TREE_OPERAND (arg0
, 1)));
8499 return fold_convert (type
, tem
);
8501 if (TREE_CODE (arg0
) == CONJ_EXPR
)
8503 tree itype
= TREE_TYPE (TREE_TYPE (arg0
));
8504 tem
= fold_build1 (IMAGPART_EXPR
, itype
, TREE_OPERAND (arg0
, 0));
8505 return fold_convert (type
, negate_expr (tem
));
8507 if (TREE_CODE (arg0
) == CALL_EXPR
)
8509 tree fn
= get_callee_fndecl (arg0
);
8510 if (fn
&& DECL_BUILT_IN_CLASS (fn
) == BUILT_IN_NORMAL
)
8511 switch (DECL_FUNCTION_CODE (fn
))
8513 CASE_FLT_FN (BUILT_IN_CEXPI
):
8514 fn
= mathfn_built_in (type
, BUILT_IN_SIN
);
8516 return build_call_expr (fn
, 1, CALL_EXPR_ARG (arg0
, 0));
8527 } /* switch (code) */
8530 /* Fold a binary expression of code CODE and type TYPE with operands
8531 OP0 and OP1, containing either a MIN-MAX or a MAX-MIN combination.
8532 Return the folded expression if folding is successful. Otherwise,
8533 return NULL_TREE. */
8536 fold_minmax (enum tree_code code
, tree type
, tree op0
, tree op1
)
8538 enum tree_code compl_code
;
8540 if (code
== MIN_EXPR
)
8541 compl_code
= MAX_EXPR
;
8542 else if (code
== MAX_EXPR
)
8543 compl_code
= MIN_EXPR
;
8547 /* MIN (MAX (a, b), b) == b. */
8548 if (TREE_CODE (op0
) == compl_code
8549 && operand_equal_p (TREE_OPERAND (op0
, 1), op1
, 0))
8550 return omit_one_operand (type
, op1
, TREE_OPERAND (op0
, 0));
8552 /* MIN (MAX (b, a), b) == b. */
8553 if (TREE_CODE (op0
) == compl_code
8554 && operand_equal_p (TREE_OPERAND (op0
, 0), op1
, 0)
8555 && reorder_operands_p (TREE_OPERAND (op0
, 1), op1
))
8556 return omit_one_operand (type
, op1
, TREE_OPERAND (op0
, 1));
8558 /* MIN (a, MAX (a, b)) == a. */
8559 if (TREE_CODE (op1
) == compl_code
8560 && operand_equal_p (op0
, TREE_OPERAND (op1
, 0), 0)
8561 && reorder_operands_p (op0
, TREE_OPERAND (op1
, 1)))
8562 return omit_one_operand (type
, op0
, TREE_OPERAND (op1
, 1));
8564 /* MIN (a, MAX (b, a)) == a. */
8565 if (TREE_CODE (op1
) == compl_code
8566 && operand_equal_p (op0
, TREE_OPERAND (op1
, 1), 0)
8567 && reorder_operands_p (op0
, TREE_OPERAND (op1
, 0)))
8568 return omit_one_operand (type
, op0
, TREE_OPERAND (op1
, 0));
8573 /* Helper that tries to canonicalize the comparison ARG0 CODE ARG1
8574 by changing CODE to reduce the magnitude of constants involved in
8575 ARG0 of the comparison.
8576 Returns a canonicalized comparison tree if a simplification was
8577 possible, otherwise returns NULL_TREE.
8578 Set *STRICT_OVERFLOW_P to true if the canonicalization is only
8579 valid if signed overflow is undefined. */
8582 maybe_canonicalize_comparison_1 (enum tree_code code
, tree type
,
8583 tree arg0
, tree arg1
,
8584 bool *strict_overflow_p
)
8586 enum tree_code code0
= TREE_CODE (arg0
);
8587 tree t
, cst0
= NULL_TREE
;
8591 /* Match A +- CST code arg1 and CST code arg1. */
8592 if (!(((code0
== MINUS_EXPR
8593 || code0
== PLUS_EXPR
)
8594 && TREE_CODE (TREE_OPERAND (arg0
, 1)) == INTEGER_CST
)
8595 || code0
== INTEGER_CST
))
8598 /* Identify the constant in arg0 and its sign. */
8599 if (code0
== INTEGER_CST
)
8602 cst0
= TREE_OPERAND (arg0
, 1);
8603 sgn0
= tree_int_cst_sgn (cst0
);
8605 /* Overflowed constants and zero will cause problems. */
8606 if (integer_zerop (cst0
)
8607 || TREE_OVERFLOW (cst0
))
8610 /* See if we can reduce the magnitude of the constant in
8611 arg0 by changing the comparison code. */
8612 if (code0
== INTEGER_CST
)
8614 /* CST <= arg1 -> CST-1 < arg1. */
8615 if (code
== LE_EXPR
&& sgn0
== 1)
8617 /* -CST < arg1 -> -CST-1 <= arg1. */
8618 else if (code
== LT_EXPR
&& sgn0
== -1)
8620 /* CST > arg1 -> CST-1 >= arg1. */
8621 else if (code
== GT_EXPR
&& sgn0
== 1)
8623 /* -CST >= arg1 -> -CST-1 > arg1. */
8624 else if (code
== GE_EXPR
&& sgn0
== -1)
8628 /* arg1 code' CST' might be more canonical. */
8633 /* A - CST < arg1 -> A - CST-1 <= arg1. */
8635 && code0
== ((sgn0
== -1) ? PLUS_EXPR
: MINUS_EXPR
))
8637 /* A + CST > arg1 -> A + CST-1 >= arg1. */
8638 else if (code
== GT_EXPR
8639 && code0
== ((sgn0
== -1) ? MINUS_EXPR
: PLUS_EXPR
))
8641 /* A + CST <= arg1 -> A + CST-1 < arg1. */
8642 else if (code
== LE_EXPR
8643 && code0
== ((sgn0
== -1) ? MINUS_EXPR
: PLUS_EXPR
))
8645 /* A - CST >= arg1 -> A - CST-1 > arg1. */
8646 else if (code
== GE_EXPR
8647 && code0
== ((sgn0
== -1) ? PLUS_EXPR
: MINUS_EXPR
))
8651 *strict_overflow_p
= true;
8654 /* Now build the constant reduced in magnitude. */
8655 t
= int_const_binop (sgn0
== -1 ? PLUS_EXPR
: MINUS_EXPR
,
8656 cst0
, build_int_cst (TREE_TYPE (cst0
), 1), 0);
8657 if (code0
!= INTEGER_CST
)
8658 t
= fold_build2 (code0
, TREE_TYPE (arg0
), TREE_OPERAND (arg0
, 0), t
);
8660 /* If swapping might yield to a more canonical form, do so. */
8662 return fold_build2 (swap_tree_comparison (code
), type
, arg1
, t
);
8664 return fold_build2 (code
, type
, t
, arg1
);
8667 /* Canonicalize the comparison ARG0 CODE ARG1 with type TYPE with undefined
8668 overflow further. Try to decrease the magnitude of constants involved
8669 by changing LE_EXPR and GE_EXPR to LT_EXPR and GT_EXPR or vice versa
8670 and put sole constants at the second argument position.
8671 Returns the canonicalized tree if changed, otherwise NULL_TREE. */
8674 maybe_canonicalize_comparison (enum tree_code code
, tree type
,
8675 tree arg0
, tree arg1
)
8678 bool strict_overflow_p
;
8679 const char * const warnmsg
= G_("assuming signed overflow does not occur "
8680 "when reducing constant in comparison");
8682 /* In principle pointers also have undefined overflow behavior,
8683 but that causes problems elsewhere. */
8684 if (!TYPE_OVERFLOW_UNDEFINED (TREE_TYPE (arg0
))
8685 || POINTER_TYPE_P (TREE_TYPE (arg0
)))
8688 /* Try canonicalization by simplifying arg0. */
8689 strict_overflow_p
= false;
8690 t
= maybe_canonicalize_comparison_1 (code
, type
, arg0
, arg1
,
8691 &strict_overflow_p
);
8694 if (strict_overflow_p
)
8695 fold_overflow_warning (warnmsg
, WARN_STRICT_OVERFLOW_MAGNITUDE
);
8699 /* Try canonicalization by simplifying arg1 using the swapped
8701 code
= swap_tree_comparison (code
);
8702 strict_overflow_p
= false;
8703 t
= maybe_canonicalize_comparison_1 (code
, type
, arg1
, arg0
,
8704 &strict_overflow_p
);
8705 if (t
&& strict_overflow_p
)
8706 fold_overflow_warning (warnmsg
, WARN_STRICT_OVERFLOW_MAGNITUDE
);
8710 /* Subroutine of fold_binary. This routine performs all of the
8711 transformations that are common to the equality/inequality
8712 operators (EQ_EXPR and NE_EXPR) and the ordering operators
8713 (LT_EXPR, LE_EXPR, GE_EXPR and GT_EXPR). Callers other than
8714 fold_binary should call fold_binary. Fold a comparison with
8715 tree code CODE and type TYPE with operands OP0 and OP1. Return
8716 the folded comparison or NULL_TREE. */
8719 fold_comparison (enum tree_code code
, tree type
, tree op0
, tree op1
)
8721 tree arg0
, arg1
, tem
;
8726 STRIP_SIGN_NOPS (arg0
);
8727 STRIP_SIGN_NOPS (arg1
);
8729 tem
= fold_relational_const (code
, type
, arg0
, arg1
);
8730 if (tem
!= NULL_TREE
)
8733 /* If one arg is a real or integer constant, put it last. */
8734 if (tree_swap_operands_p (arg0
, arg1
, true))
8735 return fold_build2 (swap_tree_comparison (code
), type
, op1
, op0
);
8737 /* Transform comparisons of the form X +- C1 CMP C2 to X CMP C2 +- C1. */
8738 if ((TREE_CODE (arg0
) == PLUS_EXPR
|| TREE_CODE (arg0
) == MINUS_EXPR
)
8739 && (TREE_CODE (TREE_OPERAND (arg0
, 1)) == INTEGER_CST
8740 && !TREE_OVERFLOW (TREE_OPERAND (arg0
, 1))
8741 && TYPE_OVERFLOW_UNDEFINED (TREE_TYPE (arg1
)))
8742 && (TREE_CODE (arg1
) == INTEGER_CST
8743 && !TREE_OVERFLOW (arg1
)))
8745 tree const1
= TREE_OPERAND (arg0
, 1);
8747 tree variable
= TREE_OPERAND (arg0
, 0);
8750 lhs_add
= TREE_CODE (arg0
) != PLUS_EXPR
;
8752 lhs
= fold_build2 (lhs_add
? PLUS_EXPR
: MINUS_EXPR
,
8753 TREE_TYPE (arg1
), const2
, const1
);
8755 /* If the constant operation overflowed this can be
8756 simplified as a comparison against INT_MAX/INT_MIN. */
8757 if (TREE_CODE (lhs
) == INTEGER_CST
8758 && TREE_OVERFLOW (lhs
))
8760 int const1_sgn
= tree_int_cst_sgn (const1
);
8761 enum tree_code code2
= code
;
8763 /* Get the sign of the constant on the lhs if the
8764 operation were VARIABLE + CONST1. */
8765 if (TREE_CODE (arg0
) == MINUS_EXPR
)
8766 const1_sgn
= -const1_sgn
;
8768 /* The sign of the constant determines if we overflowed
8769 INT_MAX (const1_sgn == -1) or INT_MIN (const1_sgn == 1).
8770 Canonicalize to the INT_MIN overflow by swapping the comparison
8772 if (const1_sgn
== -1)
8773 code2
= swap_tree_comparison (code
);
8775 /* We now can look at the canonicalized case
8776 VARIABLE + 1 CODE2 INT_MIN
8777 and decide on the result. */
8778 if (code2
== LT_EXPR
8780 || code2
== EQ_EXPR
)
8781 return omit_one_operand (type
, boolean_false_node
, variable
);
8782 else if (code2
== NE_EXPR
8784 || code2
== GT_EXPR
)
8785 return omit_one_operand (type
, boolean_true_node
, variable
);
8788 if (TREE_CODE (lhs
) == TREE_CODE (arg1
)
8789 && (TREE_CODE (lhs
) != INTEGER_CST
8790 || !TREE_OVERFLOW (lhs
)))
8792 fold_overflow_warning (("assuming signed overflow does not occur "
8793 "when changing X +- C1 cmp C2 to "
8795 WARN_STRICT_OVERFLOW_COMPARISON
);
8796 return fold_build2 (code
, type
, variable
, lhs
);
8800 /* For comparisons of pointers we can decompose it to a compile time
8801 comparison of the base objects and the offsets into the object.
8802 This requires at least one operand being an ADDR_EXPR to do more
8803 than the operand_equal_p test below. */
8804 if (POINTER_TYPE_P (TREE_TYPE (arg0
))
8805 && (TREE_CODE (arg0
) == ADDR_EXPR
8806 || TREE_CODE (arg1
) == ADDR_EXPR
))
8808 tree base0
, base1
, offset0
= NULL_TREE
, offset1
= NULL_TREE
;
8809 HOST_WIDE_INT bitsize
, bitpos0
= 0, bitpos1
= 0;
8810 enum machine_mode mode
;
8811 int volatilep
, unsignedp
;
8812 bool indirect_base0
= false;
8814 /* Get base and offset for the access. Strip ADDR_EXPR for
8815 get_inner_reference, but put it back by stripping INDIRECT_REF
8816 off the base object if possible. */
8818 if (TREE_CODE (arg0
) == ADDR_EXPR
)
8820 base0
= get_inner_reference (TREE_OPERAND (arg0
, 0),
8821 &bitsize
, &bitpos0
, &offset0
, &mode
,
8822 &unsignedp
, &volatilep
, false);
8823 if (TREE_CODE (base0
) == INDIRECT_REF
)
8824 base0
= TREE_OPERAND (base0
, 0);
8826 indirect_base0
= true;
8830 if (TREE_CODE (arg1
) == ADDR_EXPR
)
8832 base1
= get_inner_reference (TREE_OPERAND (arg1
, 0),
8833 &bitsize
, &bitpos1
, &offset1
, &mode
,
8834 &unsignedp
, &volatilep
, false);
8835 /* We have to make sure to have an indirect/non-indirect base1
8836 just the same as we did for base0. */
8837 if (TREE_CODE (base1
) == INDIRECT_REF
8839 base1
= TREE_OPERAND (base1
, 0);
8840 else if (!indirect_base0
)
8843 else if (indirect_base0
)
8846 /* If we have equivalent bases we might be able to simplify. */
8848 && operand_equal_p (base0
, base1
, 0))
8850 /* We can fold this expression to a constant if the non-constant
8851 offset parts are equal. */
8852 if (offset0
== offset1
8853 || (offset0
&& offset1
8854 && operand_equal_p (offset0
, offset1
, 0)))
8859 return build_int_cst (boolean_type_node
, bitpos0
== bitpos1
);
8861 return build_int_cst (boolean_type_node
, bitpos0
!= bitpos1
);
8863 return build_int_cst (boolean_type_node
, bitpos0
< bitpos1
);
8865 return build_int_cst (boolean_type_node
, bitpos0
<= bitpos1
);
8867 return build_int_cst (boolean_type_node
, bitpos0
>= bitpos1
);
8869 return build_int_cst (boolean_type_node
, bitpos0
> bitpos1
);
8873 /* We can simplify the comparison to a comparison of the variable
8874 offset parts if the constant offset parts are equal.
8875 Be careful to use signed size type here because otherwise we
8876 mess with array offsets in the wrong way. This is possible
8877 because pointer arithmetic is restricted to retain within an
8878 object and overflow on pointer differences is undefined as of
8879 6.5.6/8 and /9 with respect to the signed ptrdiff_t. */
8880 else if (bitpos0
== bitpos1
)
8882 tree signed_size_type_node
;
8883 signed_size_type_node
= signed_type_for (size_type_node
);
8885 /* By converting to signed size type we cover middle-end pointer
8886 arithmetic which operates on unsigned pointer types of size
8887 type size and ARRAY_REF offsets which are properly sign or
8888 zero extended from their type in case it is narrower than
8890 if (offset0
== NULL_TREE
)
8891 offset0
= build_int_cst (signed_size_type_node
, 0);
8893 offset0
= fold_convert (signed_size_type_node
, offset0
);
8894 if (offset1
== NULL_TREE
)
8895 offset1
= build_int_cst (signed_size_type_node
, 0);
8897 offset1
= fold_convert (signed_size_type_node
, offset1
);
8899 return fold_build2 (code
, type
, offset0
, offset1
);
8904 /* If this is a comparison of two exprs that look like an ARRAY_REF of the
8905 same object, then we can fold this to a comparison of the two offsets in
8906 signed size type. This is possible because pointer arithmetic is
8907 restricted to retain within an object and overflow on pointer differences
8908 is undefined as of 6.5.6/8 and /9 with respect to the signed ptrdiff_t.
8910 We check flag_wrapv directly because pointers types are unsigned,
8911 and therefore TYPE_OVERFLOW_WRAPS returns true for them. That is
8912 normally what we want to avoid certain odd overflow cases, but
8914 if (POINTER_TYPE_P (TREE_TYPE (arg0
))
8916 && !TYPE_OVERFLOW_TRAPS (TREE_TYPE (arg0
)))
8918 tree base0
, offset0
, base1
, offset1
;
8920 if (extract_array_ref (arg0
, &base0
, &offset0
)
8921 && extract_array_ref (arg1
, &base1
, &offset1
)
8922 && operand_equal_p (base0
, base1
, 0))
8924 tree signed_size_type_node
;
8925 signed_size_type_node
= signed_type_for (size_type_node
);
8927 /* By converting to signed size type we cover middle-end pointer
8928 arithmetic which operates on unsigned pointer types of size
8929 type size and ARRAY_REF offsets which are properly sign or
8930 zero extended from their type in case it is narrower than
8932 if (offset0
== NULL_TREE
)
8933 offset0
= build_int_cst (signed_size_type_node
, 0);
8935 offset0
= fold_convert (signed_size_type_node
, offset0
);
8936 if (offset1
== NULL_TREE
)
8937 offset1
= build_int_cst (signed_size_type_node
, 0);
8939 offset1
= fold_convert (signed_size_type_node
, offset1
);
8941 return fold_build2 (code
, type
, offset0
, offset1
);
8945 /* Transform comparisons of the form X +- C1 CMP Y +- C2 to
8946 X CMP Y +- C2 +- C1 for signed X, Y. This is valid if
8947 the resulting offset is smaller in absolute value than the
8949 if (TYPE_OVERFLOW_UNDEFINED (TREE_TYPE (arg0
))
8950 && (TREE_CODE (arg0
) == PLUS_EXPR
|| TREE_CODE (arg0
) == MINUS_EXPR
)
8951 && (TREE_CODE (TREE_OPERAND (arg0
, 1)) == INTEGER_CST
8952 && !TREE_OVERFLOW (TREE_OPERAND (arg0
, 1)))
8953 && (TREE_CODE (arg1
) == PLUS_EXPR
|| TREE_CODE (arg1
) == MINUS_EXPR
)
8954 && (TREE_CODE (TREE_OPERAND (arg1
, 1)) == INTEGER_CST
8955 && !TREE_OVERFLOW (TREE_OPERAND (arg1
, 1))))
8957 tree const1
= TREE_OPERAND (arg0
, 1);
8958 tree const2
= TREE_OPERAND (arg1
, 1);
8959 tree variable1
= TREE_OPERAND (arg0
, 0);
8960 tree variable2
= TREE_OPERAND (arg1
, 0);
8962 const char * const warnmsg
= G_("assuming signed overflow does not "
8963 "occur when combining constants around "
8966 /* Put the constant on the side where it doesn't overflow and is
8967 of lower absolute value than before. */
8968 cst
= int_const_binop (TREE_CODE (arg0
) == TREE_CODE (arg1
)
8969 ? MINUS_EXPR
: PLUS_EXPR
,
8971 if (!TREE_OVERFLOW (cst
)
8972 && tree_int_cst_compare (const2
, cst
) == tree_int_cst_sgn (const2
))
8974 fold_overflow_warning (warnmsg
, WARN_STRICT_OVERFLOW_COMPARISON
);
8975 return fold_build2 (code
, type
,
8977 fold_build2 (TREE_CODE (arg1
), TREE_TYPE (arg1
),
8981 cst
= int_const_binop (TREE_CODE (arg0
) == TREE_CODE (arg1
)
8982 ? MINUS_EXPR
: PLUS_EXPR
,
8984 if (!TREE_OVERFLOW (cst
)
8985 && tree_int_cst_compare (const1
, cst
) == tree_int_cst_sgn (const1
))
8987 fold_overflow_warning (warnmsg
, WARN_STRICT_OVERFLOW_COMPARISON
);
8988 return fold_build2 (code
, type
,
8989 fold_build2 (TREE_CODE (arg0
), TREE_TYPE (arg0
),
8995 /* Transform comparisons of the form X * C1 CMP 0 to X CMP 0 in the
8996 signed arithmetic case. That form is created by the compiler
8997 often enough for folding it to be of value. One example is in
8998 computing loop trip counts after Operator Strength Reduction. */
8999 if (TYPE_OVERFLOW_UNDEFINED (TREE_TYPE (arg0
))
9000 && TREE_CODE (arg0
) == MULT_EXPR
9001 && (TREE_CODE (TREE_OPERAND (arg0
, 1)) == INTEGER_CST
9002 && !TREE_OVERFLOW (TREE_OPERAND (arg0
, 1)))
9003 && integer_zerop (arg1
))
9005 tree const1
= TREE_OPERAND (arg0
, 1);
9006 tree const2
= arg1
; /* zero */
9007 tree variable1
= TREE_OPERAND (arg0
, 0);
9008 enum tree_code cmp_code
= code
;
9010 gcc_assert (!integer_zerop (const1
));
9012 fold_overflow_warning (("assuming signed overflow does not occur when "
9013 "eliminating multiplication in comparison "
9015 WARN_STRICT_OVERFLOW_COMPARISON
);
9017 /* If const1 is negative we swap the sense of the comparison. */
9018 if (tree_int_cst_sgn (const1
) < 0)
9019 cmp_code
= swap_tree_comparison (cmp_code
);
9021 return fold_build2 (cmp_code
, type
, variable1
, const2
);
9024 tem
= maybe_canonicalize_comparison (code
, type
, op0
, op1
);
9028 if (FLOAT_TYPE_P (TREE_TYPE (arg0
)))
9030 tree targ0
= strip_float_extensions (arg0
);
9031 tree targ1
= strip_float_extensions (arg1
);
9032 tree newtype
= TREE_TYPE (targ0
);
9034 if (TYPE_PRECISION (TREE_TYPE (targ1
)) > TYPE_PRECISION (newtype
))
9035 newtype
= TREE_TYPE (targ1
);
9037 /* Fold (double)float1 CMP (double)float2 into float1 CMP float2. */
9038 if (TYPE_PRECISION (newtype
) < TYPE_PRECISION (TREE_TYPE (arg0
)))
9039 return fold_build2 (code
, type
, fold_convert (newtype
, targ0
),
9040 fold_convert (newtype
, targ1
));
9042 /* (-a) CMP (-b) -> b CMP a */
9043 if (TREE_CODE (arg0
) == NEGATE_EXPR
9044 && TREE_CODE (arg1
) == NEGATE_EXPR
)
9045 return fold_build2 (code
, type
, TREE_OPERAND (arg1
, 0),
9046 TREE_OPERAND (arg0
, 0));
9048 if (TREE_CODE (arg1
) == REAL_CST
)
9050 REAL_VALUE_TYPE cst
;
9051 cst
= TREE_REAL_CST (arg1
);
9053 /* (-a) CMP CST -> a swap(CMP) (-CST) */
9054 if (TREE_CODE (arg0
) == NEGATE_EXPR
)
9055 return fold_build2 (swap_tree_comparison (code
), type
,
9056 TREE_OPERAND (arg0
, 0),
9057 build_real (TREE_TYPE (arg1
),
9058 REAL_VALUE_NEGATE (cst
)));
9060 /* IEEE doesn't distinguish +0 and -0 in comparisons. */
9061 /* a CMP (-0) -> a CMP 0 */
9062 if (REAL_VALUE_MINUS_ZERO (cst
))
9063 return fold_build2 (code
, type
, arg0
,
9064 build_real (TREE_TYPE (arg1
), dconst0
));
9066 /* x != NaN is always true, other ops are always false. */
9067 if (REAL_VALUE_ISNAN (cst
)
9068 && ! HONOR_SNANS (TYPE_MODE (TREE_TYPE (arg1
))))
9070 tem
= (code
== NE_EXPR
) ? integer_one_node
: integer_zero_node
;
9071 return omit_one_operand (type
, tem
, arg0
);
9074 /* Fold comparisons against infinity. */
9075 if (REAL_VALUE_ISINF (cst
))
9077 tem
= fold_inf_compare (code
, type
, arg0
, arg1
);
9078 if (tem
!= NULL_TREE
)
9083 /* If this is a comparison of a real constant with a PLUS_EXPR
9084 or a MINUS_EXPR of a real constant, we can convert it into a
9085 comparison with a revised real constant as long as no overflow
9086 occurs when unsafe_math_optimizations are enabled. */
9087 if (flag_unsafe_math_optimizations
9088 && TREE_CODE (arg1
) == REAL_CST
9089 && (TREE_CODE (arg0
) == PLUS_EXPR
9090 || TREE_CODE (arg0
) == MINUS_EXPR
)
9091 && TREE_CODE (TREE_OPERAND (arg0
, 1)) == REAL_CST
9092 && 0 != (tem
= const_binop (TREE_CODE (arg0
) == PLUS_EXPR
9093 ? MINUS_EXPR
: PLUS_EXPR
,
9094 arg1
, TREE_OPERAND (arg0
, 1), 0))
9095 && !TREE_OVERFLOW (tem
))
9096 return fold_build2 (code
, type
, TREE_OPERAND (arg0
, 0), tem
);
9098 /* Likewise, we can simplify a comparison of a real constant with
9099 a MINUS_EXPR whose first operand is also a real constant, i.e.
9100 (c1 - x) < c2 becomes x > c1-c2. Reordering is allowed on
9101 floating-point types only if -fassociative-math is set. */
9102 if (flag_associative_math
9103 && TREE_CODE (arg1
) == REAL_CST
9104 && TREE_CODE (arg0
) == MINUS_EXPR
9105 && TREE_CODE (TREE_OPERAND (arg0
, 0)) == REAL_CST
9106 && 0 != (tem
= const_binop (MINUS_EXPR
, TREE_OPERAND (arg0
, 0),
9108 && !TREE_OVERFLOW (tem
))
9109 return fold_build2 (swap_tree_comparison (code
), type
,
9110 TREE_OPERAND (arg0
, 1), tem
);
9112 /* Fold comparisons against built-in math functions. */
9113 if (TREE_CODE (arg1
) == REAL_CST
9114 && flag_unsafe_math_optimizations
9115 && ! flag_errno_math
)
9117 enum built_in_function fcode
= builtin_mathfn_code (arg0
);
9119 if (fcode
!= END_BUILTINS
)
9121 tem
= fold_mathfn_compare (fcode
, code
, type
, arg0
, arg1
);
9122 if (tem
!= NULL_TREE
)
9128 if (TREE_CODE (TREE_TYPE (arg0
)) == INTEGER_TYPE
9129 && (TREE_CODE (arg0
) == NOP_EXPR
9130 || TREE_CODE (arg0
) == CONVERT_EXPR
))
9132 /* If we are widening one operand of an integer comparison,
9133 see if the other operand is similarly being widened. Perhaps we
9134 can do the comparison in the narrower type. */
9135 tem
= fold_widened_comparison (code
, type
, arg0
, arg1
);
9139 /* Or if we are changing signedness. */
9140 tem
= fold_sign_changed_comparison (code
, type
, arg0
, arg1
);
9145 /* If this is comparing a constant with a MIN_EXPR or a MAX_EXPR of a
9146 constant, we can simplify it. */
9147 if (TREE_CODE (arg1
) == INTEGER_CST
9148 && (TREE_CODE (arg0
) == MIN_EXPR
9149 || TREE_CODE (arg0
) == MAX_EXPR
)
9150 && TREE_CODE (TREE_OPERAND (arg0
, 1)) == INTEGER_CST
)
9152 tem
= optimize_minmax_comparison (code
, type
, op0
, op1
);
9157 /* Simplify comparison of something with itself. (For IEEE
9158 floating-point, we can only do some of these simplifications.) */
9159 if (operand_equal_p (arg0
, arg1
, 0))
9164 if (! FLOAT_TYPE_P (TREE_TYPE (arg0
))
9165 || ! HONOR_NANS (TYPE_MODE (TREE_TYPE (arg0
))))
9166 return constant_boolean_node (1, type
);
9171 if (! FLOAT_TYPE_P (TREE_TYPE (arg0
))
9172 || ! HONOR_NANS (TYPE_MODE (TREE_TYPE (arg0
))))
9173 return constant_boolean_node (1, type
);
9174 return fold_build2 (EQ_EXPR
, type
, arg0
, arg1
);
9177 /* For NE, we can only do this simplification if integer
9178 or we don't honor IEEE floating point NaNs. */
9179 if (FLOAT_TYPE_P (TREE_TYPE (arg0
))
9180 && HONOR_NANS (TYPE_MODE (TREE_TYPE (arg0
))))
9182 /* ... fall through ... */
9185 return constant_boolean_node (0, type
);
9191 /* If we are comparing an expression that just has comparisons
9192 of two integer values, arithmetic expressions of those comparisons,
9193 and constants, we can simplify it. There are only three cases
9194 to check: the two values can either be equal, the first can be
9195 greater, or the second can be greater. Fold the expression for
9196 those three values. Since each value must be 0 or 1, we have
9197 eight possibilities, each of which corresponds to the constant 0
9198 or 1 or one of the six possible comparisons.
9200 This handles common cases like (a > b) == 0 but also handles
9201 expressions like ((x > y) - (y > x)) > 0, which supposedly
9202 occur in macroized code. */
9204 if (TREE_CODE (arg1
) == INTEGER_CST
&& TREE_CODE (arg0
) != INTEGER_CST
)
9206 tree cval1
= 0, cval2
= 0;
9209 if (twoval_comparison_p (arg0
, &cval1
, &cval2
, &save_p
)
9210 /* Don't handle degenerate cases here; they should already
9211 have been handled anyway. */
9212 && cval1
!= 0 && cval2
!= 0
9213 && ! (TREE_CONSTANT (cval1
) && TREE_CONSTANT (cval2
))
9214 && TREE_TYPE (cval1
) == TREE_TYPE (cval2
)
9215 && INTEGRAL_TYPE_P (TREE_TYPE (cval1
))
9216 && TYPE_MAX_VALUE (TREE_TYPE (cval1
))
9217 && TYPE_MAX_VALUE (TREE_TYPE (cval2
))
9218 && ! operand_equal_p (TYPE_MIN_VALUE (TREE_TYPE (cval1
)),
9219 TYPE_MAX_VALUE (TREE_TYPE (cval2
)), 0))
9221 tree maxval
= TYPE_MAX_VALUE (TREE_TYPE (cval1
));
9222 tree minval
= TYPE_MIN_VALUE (TREE_TYPE (cval1
));
9224 /* We can't just pass T to eval_subst in case cval1 or cval2
9225 was the same as ARG1. */
9228 = fold_build2 (code
, type
,
9229 eval_subst (arg0
, cval1
, maxval
,
9233 = fold_build2 (code
, type
,
9234 eval_subst (arg0
, cval1
, maxval
,
9238 = fold_build2 (code
, type
,
9239 eval_subst (arg0
, cval1
, minval
,
9243 /* All three of these results should be 0 or 1. Confirm they are.
9244 Then use those values to select the proper code to use. */
9246 if (TREE_CODE (high_result
) == INTEGER_CST
9247 && TREE_CODE (equal_result
) == INTEGER_CST
9248 && TREE_CODE (low_result
) == INTEGER_CST
)
9250 /* Make a 3-bit mask with the high-order bit being the
9251 value for `>', the next for '=', and the low for '<'. */
9252 switch ((integer_onep (high_result
) * 4)
9253 + (integer_onep (equal_result
) * 2)
9254 + integer_onep (low_result
))
9258 return omit_one_operand (type
, integer_zero_node
, arg0
);
9279 return omit_one_operand (type
, integer_one_node
, arg0
);
9283 return save_expr (build2 (code
, type
, cval1
, cval2
));
9284 return fold_build2 (code
, type
, cval1
, cval2
);
9289 /* Fold a comparison of the address of COMPONENT_REFs with the same
9290 type and component to a comparison of the address of the base
9291 object. In short, &x->a OP &y->a to x OP y and
9292 &x->a OP &y.a to x OP &y */
9293 if (TREE_CODE (arg0
) == ADDR_EXPR
9294 && TREE_CODE (TREE_OPERAND (arg0
, 0)) == COMPONENT_REF
9295 && TREE_CODE (arg1
) == ADDR_EXPR
9296 && TREE_CODE (TREE_OPERAND (arg1
, 0)) == COMPONENT_REF
)
9298 tree cref0
= TREE_OPERAND (arg0
, 0);
9299 tree cref1
= TREE_OPERAND (arg1
, 0);
9300 if (TREE_OPERAND (cref0
, 1) == TREE_OPERAND (cref1
, 1))
9302 tree op0
= TREE_OPERAND (cref0
, 0);
9303 tree op1
= TREE_OPERAND (cref1
, 0);
9304 return fold_build2 (code
, type
,
9305 fold_addr_expr (op0
),
9306 fold_addr_expr (op1
));
9310 /* We can fold X/C1 op C2 where C1 and C2 are integer constants
9311 into a single range test. */
9312 if ((TREE_CODE (arg0
) == TRUNC_DIV_EXPR
9313 || TREE_CODE (arg0
) == EXACT_DIV_EXPR
)
9314 && TREE_CODE (arg1
) == INTEGER_CST
9315 && TREE_CODE (TREE_OPERAND (arg0
, 1)) == INTEGER_CST
9316 && !integer_zerop (TREE_OPERAND (arg0
, 1))
9317 && !TREE_OVERFLOW (TREE_OPERAND (arg0
, 1))
9318 && !TREE_OVERFLOW (arg1
))
9320 tem
= fold_div_compare (code
, type
, arg0
, arg1
);
9321 if (tem
!= NULL_TREE
)
9325 /* Fold ~X op ~Y as Y op X. */
9326 if (TREE_CODE (arg0
) == BIT_NOT_EXPR
9327 && TREE_CODE (arg1
) == BIT_NOT_EXPR
)
9329 tree cmp_type
= TREE_TYPE (TREE_OPERAND (arg0
, 0));
9330 return fold_build2 (code
, type
,
9331 fold_convert (cmp_type
, TREE_OPERAND (arg1
, 0)),
9332 TREE_OPERAND (arg0
, 0));
9335 /* Fold ~X op C as X op' ~C, where op' is the swapped comparison. */
9336 if (TREE_CODE (arg0
) == BIT_NOT_EXPR
9337 && TREE_CODE (arg1
) == INTEGER_CST
)
9339 tree cmp_type
= TREE_TYPE (TREE_OPERAND (arg0
, 0));
9340 return fold_build2 (swap_tree_comparison (code
), type
,
9341 TREE_OPERAND (arg0
, 0),
9342 fold_build1 (BIT_NOT_EXPR
, cmp_type
,
9343 fold_convert (cmp_type
, arg1
)));
9350 /* Subroutine of fold_binary. Optimize complex multiplications of the
9351 form z * conj(z), as pow(realpart(z),2) + pow(imagpart(z),2). The
9352 argument EXPR represents the expression "z" of type TYPE. */
9355 fold_mult_zconjz (tree type
, tree expr
)
9357 tree itype
= TREE_TYPE (type
);
9358 tree rpart
, ipart
, tem
;
9360 if (TREE_CODE (expr
) == COMPLEX_EXPR
)
9362 rpart
= TREE_OPERAND (expr
, 0);
9363 ipart
= TREE_OPERAND (expr
, 1);
9365 else if (TREE_CODE (expr
) == COMPLEX_CST
)
9367 rpart
= TREE_REALPART (expr
);
9368 ipart
= TREE_IMAGPART (expr
);
9372 expr
= save_expr (expr
);
9373 rpart
= fold_build1 (REALPART_EXPR
, itype
, expr
);
9374 ipart
= fold_build1 (IMAGPART_EXPR
, itype
, expr
);
9377 rpart
= save_expr (rpart
);
9378 ipart
= save_expr (ipart
);
9379 tem
= fold_build2 (PLUS_EXPR
, itype
,
9380 fold_build2 (MULT_EXPR
, itype
, rpart
, rpart
),
9381 fold_build2 (MULT_EXPR
, itype
, ipart
, ipart
));
9382 return fold_build2 (COMPLEX_EXPR
, type
, tem
,
9383 fold_convert (itype
, integer_zero_node
));
9387 /* Subroutine of fold_binary. If P is the value of EXPR, computes
9388 power-of-two M and (arbitrary) N such that M divides (P-N). This condition
9389 guarantees that P and N have the same least significant log2(M) bits.
9390 N is not otherwise constrained. In particular, N is not normalized to
9391 0 <= N < M as is common. In general, the precise value of P is unknown.
9392 M is chosen as large as possible such that constant N can be determined.
9394 Returns M and sets *RESIDUE to N. */
9396 static unsigned HOST_WIDE_INT
9397 get_pointer_modulus_and_residue (tree expr
, unsigned HOST_WIDE_INT
*residue
)
9399 enum tree_code code
;
9403 code
= TREE_CODE (expr
);
9404 if (code
== ADDR_EXPR
)
9406 expr
= TREE_OPERAND (expr
, 0);
9407 if (handled_component_p (expr
))
9409 HOST_WIDE_INT bitsize
, bitpos
;
9411 enum machine_mode mode
;
9412 int unsignedp
, volatilep
;
9414 expr
= get_inner_reference (expr
, &bitsize
, &bitpos
, &offset
,
9415 &mode
, &unsignedp
, &volatilep
, false);
9416 *residue
= bitpos
/ BITS_PER_UNIT
;
9419 if (TREE_CODE (offset
) == INTEGER_CST
)
9420 *residue
+= TREE_INT_CST_LOW (offset
);
9422 /* We don't handle more complicated offset expressions. */
9428 return DECL_ALIGN_UNIT (expr
);
9430 else if (code
== POINTER_PLUS_EXPR
)
9433 unsigned HOST_WIDE_INT modulus
;
9434 enum tree_code inner_code
;
9436 op0
= TREE_OPERAND (expr
, 0);
9438 modulus
= get_pointer_modulus_and_residue (op0
, residue
);
9440 op1
= TREE_OPERAND (expr
, 1);
9442 inner_code
= TREE_CODE (op1
);
9443 if (inner_code
== INTEGER_CST
)
9445 *residue
+= TREE_INT_CST_LOW (op1
);
9448 else if (inner_code
== MULT_EXPR
)
9450 op1
= TREE_OPERAND (op1
, 1);
9451 if (TREE_CODE (op1
) == INTEGER_CST
)
9453 unsigned HOST_WIDE_INT align
;
9455 /* Compute the greatest power-of-2 divisor of op1. */
9456 align
= TREE_INT_CST_LOW (op1
);
9459 /* If align is non-zero and less than *modulus, replace
9460 *modulus with align., If align is 0, then either op1 is 0
9461 or the greatest power-of-2 divisor of op1 doesn't fit in an
9462 unsigned HOST_WIDE_INT. In either case, no additional
9463 constraint is imposed. */
9465 modulus
= MIN (modulus
, align
);
9472 /* If we get here, we were unable to determine anything useful about the
9478 /* Fold a binary expression of code CODE and type TYPE with operands
9479 OP0 and OP1. Return the folded expression if folding is
9480 successful. Otherwise, return NULL_TREE. */
9483 fold_binary (enum tree_code code
, tree type
, tree op0
, tree op1
)
9485 enum tree_code_class kind
= TREE_CODE_CLASS (code
);
9486 tree arg0
, arg1
, tem
;
9487 tree t1
= NULL_TREE
;
9488 bool strict_overflow_p
;
9490 gcc_assert ((IS_EXPR_CODE_CLASS (kind
)
9491 || IS_GIMPLE_STMT_CODE_CLASS (kind
))
9492 && TREE_CODE_LENGTH (code
) == 2
9494 && op1
!= NULL_TREE
);
9499 /* Strip any conversions that don't change the mode. This is
9500 safe for every expression, except for a comparison expression
9501 because its signedness is derived from its operands. So, in
9502 the latter case, only strip conversions that don't change the
9505 Note that this is done as an internal manipulation within the
9506 constant folder, in order to find the simplest representation
9507 of the arguments so that their form can be studied. In any
9508 cases, the appropriate type conversions should be put back in
9509 the tree that will get out of the constant folder. */
9511 if (kind
== tcc_comparison
)
9513 STRIP_SIGN_NOPS (arg0
);
9514 STRIP_SIGN_NOPS (arg1
);
9522 /* Note that TREE_CONSTANT isn't enough: static var addresses are
9523 constant but we can't do arithmetic on them. */
9524 if ((TREE_CODE (arg0
) == INTEGER_CST
&& TREE_CODE (arg1
) == INTEGER_CST
)
9525 || (TREE_CODE (arg0
) == REAL_CST
&& TREE_CODE (arg1
) == REAL_CST
)
9526 || (TREE_CODE (arg0
) == FIXED_CST
&& TREE_CODE (arg1
) == FIXED_CST
)
9527 || (TREE_CODE (arg0
) == FIXED_CST
&& TREE_CODE (arg1
) == INTEGER_CST
)
9528 || (TREE_CODE (arg0
) == COMPLEX_CST
&& TREE_CODE (arg1
) == COMPLEX_CST
)
9529 || (TREE_CODE (arg0
) == VECTOR_CST
&& TREE_CODE (arg1
) == VECTOR_CST
))
9531 if (kind
== tcc_binary
)
9533 /* Make sure type and arg0 have the same saturating flag. */
9534 gcc_assert (TYPE_SATURATING (type
)
9535 == TYPE_SATURATING (TREE_TYPE (arg0
)));
9536 tem
= const_binop (code
, arg0
, arg1
, 0);
9538 else if (kind
== tcc_comparison
)
9539 tem
= fold_relational_const (code
, type
, arg0
, arg1
);
9543 if (tem
!= NULL_TREE
)
9545 if (TREE_TYPE (tem
) != type
)
9546 tem
= fold_convert (type
, tem
);
9551 /* If this is a commutative operation, and ARG0 is a constant, move it
9552 to ARG1 to reduce the number of tests below. */
9553 if (commutative_tree_code (code
)
9554 && tree_swap_operands_p (arg0
, arg1
, true))
9555 return fold_build2 (code
, type
, op1
, op0
);
9557 /* ARG0 is the first operand of EXPR, and ARG1 is the second operand.
9559 First check for cases where an arithmetic operation is applied to a
9560 compound, conditional, or comparison operation. Push the arithmetic
9561 operation inside the compound or conditional to see if any folding
9562 can then be done. Convert comparison to conditional for this purpose.
9563 The also optimizes non-constant cases that used to be done in
9566 Before we do that, see if this is a BIT_AND_EXPR or a BIT_IOR_EXPR,
9567 one of the operands is a comparison and the other is a comparison, a
9568 BIT_AND_EXPR with the constant 1, or a truth value. In that case, the
9569 code below would make the expression more complex. Change it to a
9570 TRUTH_{AND,OR}_EXPR. Likewise, convert a similar NE_EXPR to
9571 TRUTH_XOR_EXPR and an EQ_EXPR to the inversion of a TRUTH_XOR_EXPR. */
9573 if ((code
== BIT_AND_EXPR
|| code
== BIT_IOR_EXPR
9574 || code
== EQ_EXPR
|| code
== NE_EXPR
)
9575 && ((truth_value_p (TREE_CODE (arg0
))
9576 && (truth_value_p (TREE_CODE (arg1
))
9577 || (TREE_CODE (arg1
) == BIT_AND_EXPR
9578 && integer_onep (TREE_OPERAND (arg1
, 1)))))
9579 || (truth_value_p (TREE_CODE (arg1
))
9580 && (truth_value_p (TREE_CODE (arg0
))
9581 || (TREE_CODE (arg0
) == BIT_AND_EXPR
9582 && integer_onep (TREE_OPERAND (arg0
, 1)))))))
9584 tem
= fold_build2 (code
== BIT_AND_EXPR
? TRUTH_AND_EXPR
9585 : code
== BIT_IOR_EXPR
? TRUTH_OR_EXPR
9588 fold_convert (boolean_type_node
, arg0
),
9589 fold_convert (boolean_type_node
, arg1
));
9591 if (code
== EQ_EXPR
)
9592 tem
= invert_truthvalue (tem
);
9594 return fold_convert (type
, tem
);
9597 if (TREE_CODE_CLASS (code
) == tcc_binary
9598 || TREE_CODE_CLASS (code
) == tcc_comparison
)
9600 if (TREE_CODE (arg0
) == COMPOUND_EXPR
)
9601 return build2 (COMPOUND_EXPR
, type
, TREE_OPERAND (arg0
, 0),
9602 fold_build2 (code
, type
,
9603 TREE_OPERAND (arg0
, 1), op1
));
9604 if (TREE_CODE (arg1
) == COMPOUND_EXPR
9605 && reorder_operands_p (arg0
, TREE_OPERAND (arg1
, 0)))
9606 return build2 (COMPOUND_EXPR
, type
, TREE_OPERAND (arg1
, 0),
9607 fold_build2 (code
, type
,
9608 op0
, TREE_OPERAND (arg1
, 1)));
9610 if (TREE_CODE (arg0
) == COND_EXPR
|| COMPARISON_CLASS_P (arg0
))
9612 tem
= fold_binary_op_with_conditional_arg (code
, type
, op0
, op1
,
9614 /*cond_first_p=*/1);
9615 if (tem
!= NULL_TREE
)
9619 if (TREE_CODE (arg1
) == COND_EXPR
|| COMPARISON_CLASS_P (arg1
))
9621 tem
= fold_binary_op_with_conditional_arg (code
, type
, op0
, op1
,
9623 /*cond_first_p=*/0);
9624 if (tem
!= NULL_TREE
)
9631 case POINTER_PLUS_EXPR
:
9632 /* 0 +p index -> (type)index */
9633 if (integer_zerop (arg0
))
9634 return non_lvalue (fold_convert (type
, arg1
));
9636 /* PTR +p 0 -> PTR */
9637 if (integer_zerop (arg1
))
9638 return non_lvalue (fold_convert (type
, arg0
));
9640 /* INT +p INT -> (PTR)(INT + INT). Stripping types allows for this. */
9641 if (INTEGRAL_TYPE_P (TREE_TYPE (arg1
))
9642 && INTEGRAL_TYPE_P (TREE_TYPE (arg0
)))
9643 return fold_convert (type
, fold_build2 (PLUS_EXPR
, sizetype
,
9644 fold_convert (sizetype
, arg1
),
9645 fold_convert (sizetype
, arg0
)));
9647 /* index +p PTR -> PTR +p index */
9648 if (POINTER_TYPE_P (TREE_TYPE (arg1
))
9649 && INTEGRAL_TYPE_P (TREE_TYPE (arg0
)))
9650 return fold_build2 (POINTER_PLUS_EXPR
, type
,
9651 fold_convert (type
, arg1
),
9652 fold_convert (sizetype
, arg0
));
9654 /* (PTR +p B) +p A -> PTR +p (B + A) */
9655 if (TREE_CODE (arg0
) == POINTER_PLUS_EXPR
)
9658 tree arg01
= fold_convert (sizetype
, TREE_OPERAND (arg0
, 1));
9659 tree arg00
= TREE_OPERAND (arg0
, 0);
9660 inner
= fold_build2 (PLUS_EXPR
, sizetype
,
9661 arg01
, fold_convert (sizetype
, arg1
));
9662 return fold_convert (type
,
9663 fold_build2 (POINTER_PLUS_EXPR
,
9664 TREE_TYPE (arg00
), arg00
, inner
));
9667 /* PTR_CST +p CST -> CST1 */
9668 if (TREE_CODE (arg0
) == INTEGER_CST
&& TREE_CODE (arg1
) == INTEGER_CST
)
9669 return fold_build2 (PLUS_EXPR
, type
, arg0
, fold_convert (type
, arg1
));
9671 /* Try replacing &a[i1] +p c * i2 with &a[i1 + i2], if c is step
9672 of the array. Loop optimizer sometimes produce this type of
9674 if (TREE_CODE (arg0
) == ADDR_EXPR
)
9676 tem
= try_move_mult_to_index (arg0
, fold_convert (sizetype
, arg1
));
9678 return fold_convert (type
, tem
);
9684 /* PTR + INT -> (INT)(PTR p+ INT) */
9685 if (POINTER_TYPE_P (TREE_TYPE (arg0
))
9686 && INTEGRAL_TYPE_P (TREE_TYPE (arg1
)))
9687 return fold_convert (type
, fold_build2 (POINTER_PLUS_EXPR
,
9690 fold_convert (sizetype
, arg1
)));
9691 /* INT + PTR -> (INT)(PTR p+ INT) */
9692 if (POINTER_TYPE_P (TREE_TYPE (arg1
))
9693 && INTEGRAL_TYPE_P (TREE_TYPE (arg0
)))
9694 return fold_convert (type
, fold_build2 (POINTER_PLUS_EXPR
,
9697 fold_convert (sizetype
, arg0
)));
9698 /* A + (-B) -> A - B */
9699 if (TREE_CODE (arg1
) == NEGATE_EXPR
)
9700 return fold_build2 (MINUS_EXPR
, type
,
9701 fold_convert (type
, arg0
),
9702 fold_convert (type
, TREE_OPERAND (arg1
, 0)));
9703 /* (-A) + B -> B - A */
9704 if (TREE_CODE (arg0
) == NEGATE_EXPR
9705 && reorder_operands_p (TREE_OPERAND (arg0
, 0), arg1
))
9706 return fold_build2 (MINUS_EXPR
, type
,
9707 fold_convert (type
, arg1
),
9708 fold_convert (type
, TREE_OPERAND (arg0
, 0)));
9710 if (INTEGRAL_TYPE_P (type
))
9712 /* Convert ~A + 1 to -A. */
9713 if (TREE_CODE (arg0
) == BIT_NOT_EXPR
9714 && integer_onep (arg1
))
9715 return fold_build1 (NEGATE_EXPR
, type
, TREE_OPERAND (arg0
, 0));
9718 if (TREE_CODE (arg0
) == BIT_NOT_EXPR
9719 && !TYPE_OVERFLOW_TRAPS (type
))
9721 tree tem
= TREE_OPERAND (arg0
, 0);
9724 if (operand_equal_p (tem
, arg1
, 0))
9726 t1
= build_int_cst_type (type
, -1);
9727 return omit_one_operand (type
, t1
, arg1
);
9732 if (TREE_CODE (arg1
) == BIT_NOT_EXPR
9733 && !TYPE_OVERFLOW_TRAPS (type
))
9735 tree tem
= TREE_OPERAND (arg1
, 0);
9738 if (operand_equal_p (arg0
, tem
, 0))
9740 t1
= build_int_cst_type (type
, -1);
9741 return omit_one_operand (type
, t1
, arg0
);
9746 /* Handle (A1 * C1) + (A2 * C2) with A1, A2 or C1, C2 being the
9747 same or one. Make sure type is not saturating.
9748 fold_plusminus_mult_expr will re-associate. */
9749 if ((TREE_CODE (arg0
) == MULT_EXPR
9750 || TREE_CODE (arg1
) == MULT_EXPR
)
9751 && !TYPE_SATURATING (type
)
9752 && (!FLOAT_TYPE_P (type
) || flag_associative_math
))
9754 tree tem
= fold_plusminus_mult_expr (code
, type
, arg0
, arg1
);
9759 if (! FLOAT_TYPE_P (type
))
9761 if (integer_zerop (arg1
))
9762 return non_lvalue (fold_convert (type
, arg0
));
9764 /* If we are adding two BIT_AND_EXPR's, both of which are and'ing
9765 with a constant, and the two constants have no bits in common,
9766 we should treat this as a BIT_IOR_EXPR since this may produce more
9768 if (TREE_CODE (arg0
) == BIT_AND_EXPR
9769 && TREE_CODE (arg1
) == BIT_AND_EXPR
9770 && TREE_CODE (TREE_OPERAND (arg0
, 1)) == INTEGER_CST
9771 && TREE_CODE (TREE_OPERAND (arg1
, 1)) == INTEGER_CST
9772 && integer_zerop (const_binop (BIT_AND_EXPR
,
9773 TREE_OPERAND (arg0
, 1),
9774 TREE_OPERAND (arg1
, 1), 0)))
9776 code
= BIT_IOR_EXPR
;
9780 /* Reassociate (plus (plus (mult) (foo)) (mult)) as
9781 (plus (plus (mult) (mult)) (foo)) so that we can
9782 take advantage of the factoring cases below. */
9783 if (((TREE_CODE (arg0
) == PLUS_EXPR
9784 || TREE_CODE (arg0
) == MINUS_EXPR
)
9785 && TREE_CODE (arg1
) == MULT_EXPR
)
9786 || ((TREE_CODE (arg1
) == PLUS_EXPR
9787 || TREE_CODE (arg1
) == MINUS_EXPR
)
9788 && TREE_CODE (arg0
) == MULT_EXPR
))
9790 tree parg0
, parg1
, parg
, marg
;
9791 enum tree_code pcode
;
9793 if (TREE_CODE (arg1
) == MULT_EXPR
)
9794 parg
= arg0
, marg
= arg1
;
9796 parg
= arg1
, marg
= arg0
;
9797 pcode
= TREE_CODE (parg
);
9798 parg0
= TREE_OPERAND (parg
, 0);
9799 parg1
= TREE_OPERAND (parg
, 1);
9803 if (TREE_CODE (parg0
) == MULT_EXPR
9804 && TREE_CODE (parg1
) != MULT_EXPR
)
9805 return fold_build2 (pcode
, type
,
9806 fold_build2 (PLUS_EXPR
, type
,
9807 fold_convert (type
, parg0
),
9808 fold_convert (type
, marg
)),
9809 fold_convert (type
, parg1
));
9810 if (TREE_CODE (parg0
) != MULT_EXPR
9811 && TREE_CODE (parg1
) == MULT_EXPR
)
9812 return fold_build2 (PLUS_EXPR
, type
,
9813 fold_convert (type
, parg0
),
9814 fold_build2 (pcode
, type
,
9815 fold_convert (type
, marg
),
9822 /* See if ARG1 is zero and X + ARG1 reduces to X. */
9823 if (fold_real_zero_addition_p (TREE_TYPE (arg0
), arg1
, 0))
9824 return non_lvalue (fold_convert (type
, arg0
));
9826 /* Likewise if the operands are reversed. */
9827 if (fold_real_zero_addition_p (TREE_TYPE (arg1
), arg0
, 0))
9828 return non_lvalue (fold_convert (type
, arg1
));
9830 /* Convert X + -C into X - C. */
9831 if (TREE_CODE (arg1
) == REAL_CST
9832 && REAL_VALUE_NEGATIVE (TREE_REAL_CST (arg1
)))
9834 tem
= fold_negate_const (arg1
, type
);
9835 if (!TREE_OVERFLOW (arg1
) || !flag_trapping_math
)
9836 return fold_build2 (MINUS_EXPR
, type
,
9837 fold_convert (type
, arg0
),
9838 fold_convert (type
, tem
));
9841 /* Fold __complex__ ( x, 0 ) + __complex__ ( 0, y )
9842 to __complex__ ( x, y ). This is not the same for SNaNs or
9843 if signed zeros are involved. */
9844 if (!HONOR_SNANS (TYPE_MODE (TREE_TYPE (arg0
)))
9845 && !HONOR_SIGNED_ZEROS (TYPE_MODE (TREE_TYPE (arg0
)))
9846 && COMPLEX_FLOAT_TYPE_P (TREE_TYPE (arg0
)))
9848 tree rtype
= TREE_TYPE (TREE_TYPE (arg0
));
9849 tree arg0r
= fold_unary (REALPART_EXPR
, rtype
, arg0
);
9850 tree arg0i
= fold_unary (IMAGPART_EXPR
, rtype
, arg0
);
9851 bool arg0rz
= false, arg0iz
= false;
9852 if ((arg0r
&& (arg0rz
= real_zerop (arg0r
)))
9853 || (arg0i
&& (arg0iz
= real_zerop (arg0i
))))
9855 tree arg1r
= fold_unary (REALPART_EXPR
, rtype
, arg1
);
9856 tree arg1i
= fold_unary (IMAGPART_EXPR
, rtype
, arg1
);
9857 if (arg0rz
&& arg1i
&& real_zerop (arg1i
))
9859 tree rp
= arg1r
? arg1r
9860 : build1 (REALPART_EXPR
, rtype
, arg1
);
9861 tree ip
= arg0i
? arg0i
9862 : build1 (IMAGPART_EXPR
, rtype
, arg0
);
9863 return fold_build2 (COMPLEX_EXPR
, type
, rp
, ip
);
9865 else if (arg0iz
&& arg1r
&& real_zerop (arg1r
))
9867 tree rp
= arg0r
? arg0r
9868 : build1 (REALPART_EXPR
, rtype
, arg0
);
9869 tree ip
= arg1i
? arg1i
9870 : build1 (IMAGPART_EXPR
, rtype
, arg1
);
9871 return fold_build2 (COMPLEX_EXPR
, type
, rp
, ip
);
9876 if (flag_unsafe_math_optimizations
9877 && (TREE_CODE (arg0
) == RDIV_EXPR
|| TREE_CODE (arg0
) == MULT_EXPR
)
9878 && (TREE_CODE (arg1
) == RDIV_EXPR
|| TREE_CODE (arg1
) == MULT_EXPR
)
9879 && (tem
= distribute_real_division (code
, type
, arg0
, arg1
)))
9882 /* Convert x+x into x*2.0. */
9883 if (operand_equal_p (arg0
, arg1
, 0)
9884 && SCALAR_FLOAT_TYPE_P (type
))
9885 return fold_build2 (MULT_EXPR
, type
, arg0
,
9886 build_real (type
, dconst2
));
9888 /* Convert a + (b*c + d*e) into (a + b*c) + d*e.
9889 We associate floats only if the user has specified
9890 -fassociative-math. */
9891 if (flag_associative_math
9892 && TREE_CODE (arg1
) == PLUS_EXPR
9893 && TREE_CODE (arg0
) != MULT_EXPR
)
9895 tree tree10
= TREE_OPERAND (arg1
, 0);
9896 tree tree11
= TREE_OPERAND (arg1
, 1);
9897 if (TREE_CODE (tree11
) == MULT_EXPR
9898 && TREE_CODE (tree10
) == MULT_EXPR
)
9901 tree0
= fold_build2 (PLUS_EXPR
, type
, arg0
, tree10
);
9902 return fold_build2 (PLUS_EXPR
, type
, tree0
, tree11
);
9905 /* Convert (b*c + d*e) + a into b*c + (d*e +a).
9906 We associate floats only if the user has specified
9907 -fassociative-math. */
9908 if (flag_associative_math
9909 && TREE_CODE (arg0
) == PLUS_EXPR
9910 && TREE_CODE (arg1
) != MULT_EXPR
)
9912 tree tree00
= TREE_OPERAND (arg0
, 0);
9913 tree tree01
= TREE_OPERAND (arg0
, 1);
9914 if (TREE_CODE (tree01
) == MULT_EXPR
9915 && TREE_CODE (tree00
) == MULT_EXPR
)
9918 tree0
= fold_build2 (PLUS_EXPR
, type
, tree01
, arg1
);
9919 return fold_build2 (PLUS_EXPR
, type
, tree00
, tree0
);
9925 /* (A << C1) + (A >> C2) if A is unsigned and C1+C2 is the size of A
9926 is a rotate of A by C1 bits. */
9927 /* (A << B) + (A >> (Z - B)) if A is unsigned and Z is the size of A
9928 is a rotate of A by B bits. */
9930 enum tree_code code0
, code1
;
9931 code0
= TREE_CODE (arg0
);
9932 code1
= TREE_CODE (arg1
);
9933 if (((code0
== RSHIFT_EXPR
&& code1
== LSHIFT_EXPR
)
9934 || (code1
== RSHIFT_EXPR
&& code0
== LSHIFT_EXPR
))
9935 && operand_equal_p (TREE_OPERAND (arg0
, 0),
9936 TREE_OPERAND (arg1
, 0), 0)
9937 && TYPE_UNSIGNED (TREE_TYPE (TREE_OPERAND (arg0
, 0))))
9939 tree tree01
, tree11
;
9940 enum tree_code code01
, code11
;
9942 tree01
= TREE_OPERAND (arg0
, 1);
9943 tree11
= TREE_OPERAND (arg1
, 1);
9944 STRIP_NOPS (tree01
);
9945 STRIP_NOPS (tree11
);
9946 code01
= TREE_CODE (tree01
);
9947 code11
= TREE_CODE (tree11
);
9948 if (code01
== INTEGER_CST
9949 && code11
== INTEGER_CST
9950 && TREE_INT_CST_HIGH (tree01
) == 0
9951 && TREE_INT_CST_HIGH (tree11
) == 0
9952 && ((TREE_INT_CST_LOW (tree01
) + TREE_INT_CST_LOW (tree11
))
9953 == TYPE_PRECISION (TREE_TYPE (TREE_OPERAND (arg0
, 0)))))
9954 return build2 (LROTATE_EXPR
, type
, TREE_OPERAND (arg0
, 0),
9955 code0
== LSHIFT_EXPR
? tree01
: tree11
);
9956 else if (code11
== MINUS_EXPR
)
9958 tree tree110
, tree111
;
9959 tree110
= TREE_OPERAND (tree11
, 0);
9960 tree111
= TREE_OPERAND (tree11
, 1);
9961 STRIP_NOPS (tree110
);
9962 STRIP_NOPS (tree111
);
9963 if (TREE_CODE (tree110
) == INTEGER_CST
9964 && 0 == compare_tree_int (tree110
,
9966 (TREE_TYPE (TREE_OPERAND
9968 && operand_equal_p (tree01
, tree111
, 0))
9969 return build2 ((code0
== LSHIFT_EXPR
9972 type
, TREE_OPERAND (arg0
, 0), tree01
);
9974 else if (code01
== MINUS_EXPR
)
9976 tree tree010
, tree011
;
9977 tree010
= TREE_OPERAND (tree01
, 0);
9978 tree011
= TREE_OPERAND (tree01
, 1);
9979 STRIP_NOPS (tree010
);
9980 STRIP_NOPS (tree011
);
9981 if (TREE_CODE (tree010
) == INTEGER_CST
9982 && 0 == compare_tree_int (tree010
,
9984 (TREE_TYPE (TREE_OPERAND
9986 && operand_equal_p (tree11
, tree011
, 0))
9987 return build2 ((code0
!= LSHIFT_EXPR
9990 type
, TREE_OPERAND (arg0
, 0), tree11
);
9996 /* In most languages, can't associate operations on floats through
9997 parentheses. Rather than remember where the parentheses were, we
9998 don't associate floats at all, unless the user has specified
10000 And, we need to make sure type is not saturating. */
10002 if ((! FLOAT_TYPE_P (type
) || flag_associative_math
)
10003 && !TYPE_SATURATING (type
))
10005 tree var0
, con0
, lit0
, minus_lit0
;
10006 tree var1
, con1
, lit1
, minus_lit1
;
10009 /* Split both trees into variables, constants, and literals. Then
10010 associate each group together, the constants with literals,
10011 then the result with variables. This increases the chances of
10012 literals being recombined later and of generating relocatable
10013 expressions for the sum of a constant and literal. */
10014 var0
= split_tree (arg0
, code
, &con0
, &lit0
, &minus_lit0
, 0);
10015 var1
= split_tree (arg1
, code
, &con1
, &lit1
, &minus_lit1
,
10016 code
== MINUS_EXPR
);
10018 /* With undefined overflow we can only associate constants
10019 with one variable. */
10020 if ((POINTER_TYPE_P (type
)
10021 || (INTEGRAL_TYPE_P (type
) && !TYPE_OVERFLOW_WRAPS (type
)))
10027 if (TREE_CODE (tmp0
) == NEGATE_EXPR
)
10028 tmp0
= TREE_OPERAND (tmp0
, 0);
10029 if (TREE_CODE (tmp1
) == NEGATE_EXPR
)
10030 tmp1
= TREE_OPERAND (tmp1
, 0);
10031 /* The only case we can still associate with two variables
10032 is if they are the same, modulo negation. */
10033 if (!operand_equal_p (tmp0
, tmp1
, 0))
10037 /* Only do something if we found more than two objects. Otherwise,
10038 nothing has changed and we risk infinite recursion. */
10040 && (2 < ((var0
!= 0) + (var1
!= 0)
10041 + (con0
!= 0) + (con1
!= 0)
10042 + (lit0
!= 0) + (lit1
!= 0)
10043 + (minus_lit0
!= 0) + (minus_lit1
!= 0))))
10045 /* Recombine MINUS_EXPR operands by using PLUS_EXPR. */
10046 if (code
== MINUS_EXPR
)
10049 var0
= associate_trees (var0
, var1
, code
, type
);
10050 con0
= associate_trees (con0
, con1
, code
, type
);
10051 lit0
= associate_trees (lit0
, lit1
, code
, type
);
10052 minus_lit0
= associate_trees (minus_lit0
, minus_lit1
, code
, type
);
10054 /* Preserve the MINUS_EXPR if the negative part of the literal is
10055 greater than the positive part. Otherwise, the multiplicative
10056 folding code (i.e extract_muldiv) may be fooled in case
10057 unsigned constants are subtracted, like in the following
10058 example: ((X*2 + 4) - 8U)/2. */
10059 if (minus_lit0
&& lit0
)
10061 if (TREE_CODE (lit0
) == INTEGER_CST
10062 && TREE_CODE (minus_lit0
) == INTEGER_CST
10063 && tree_int_cst_lt (lit0
, minus_lit0
))
10065 minus_lit0
= associate_trees (minus_lit0
, lit0
,
10071 lit0
= associate_trees (lit0
, minus_lit0
,
10079 return fold_convert (type
,
10080 associate_trees (var0
, minus_lit0
,
10081 MINUS_EXPR
, type
));
10084 con0
= associate_trees (con0
, minus_lit0
,
10086 return fold_convert (type
,
10087 associate_trees (var0
, con0
,
10092 con0
= associate_trees (con0
, lit0
, code
, type
);
10093 return fold_convert (type
, associate_trees (var0
, con0
,
10101 /* Pointer simplifications for subtraction, simple reassociations. */
10102 if (POINTER_TYPE_P (TREE_TYPE (arg1
)) && POINTER_TYPE_P (TREE_TYPE (arg0
)))
10104 /* (PTR0 p+ A) - (PTR1 p+ B) -> (PTR0 - PTR1) + (A - B) */
10105 if (TREE_CODE (arg0
) == POINTER_PLUS_EXPR
10106 && TREE_CODE (arg1
) == POINTER_PLUS_EXPR
)
10108 tree arg00
= fold_convert (type
, TREE_OPERAND (arg0
, 0));
10109 tree arg01
= fold_convert (type
, TREE_OPERAND (arg0
, 1));
10110 tree arg10
= fold_convert (type
, TREE_OPERAND (arg1
, 0));
10111 tree arg11
= fold_convert (type
, TREE_OPERAND (arg1
, 1));
10112 return fold_build2 (PLUS_EXPR
, type
,
10113 fold_build2 (MINUS_EXPR
, type
, arg00
, arg10
),
10114 fold_build2 (MINUS_EXPR
, type
, arg01
, arg11
));
10116 /* (PTR0 p+ A) - PTR1 -> (PTR0 - PTR1) + A, assuming PTR0 - PTR1 simplifies. */
10117 else if (TREE_CODE (arg0
) == POINTER_PLUS_EXPR
)
10119 tree arg00
= fold_convert (type
, TREE_OPERAND (arg0
, 0));
10120 tree arg01
= fold_convert (type
, TREE_OPERAND (arg0
, 1));
10121 tree tmp
= fold_binary (MINUS_EXPR
, type
, arg00
, fold_convert (type
, arg1
));
10123 return fold_build2 (PLUS_EXPR
, type
, tmp
, arg01
);
10126 /* A - (-B) -> A + B */
10127 if (TREE_CODE (arg1
) == NEGATE_EXPR
)
10128 return fold_build2 (PLUS_EXPR
, type
, arg0
, TREE_OPERAND (arg1
, 0));
10129 /* (-A) - B -> (-B) - A where B is easily negated and we can swap. */
10130 if (TREE_CODE (arg0
) == NEGATE_EXPR
10131 && (FLOAT_TYPE_P (type
)
10132 || INTEGRAL_TYPE_P (type
))
10133 && negate_expr_p (arg1
)
10134 && reorder_operands_p (arg0
, arg1
))
10135 return fold_build2 (MINUS_EXPR
, type
, negate_expr (arg1
),
10136 TREE_OPERAND (arg0
, 0));
10137 /* Convert -A - 1 to ~A. */
10138 if (INTEGRAL_TYPE_P (type
)
10139 && TREE_CODE (arg0
) == NEGATE_EXPR
10140 && integer_onep (arg1
)
10141 && !TYPE_OVERFLOW_TRAPS (type
))
10142 return fold_build1 (BIT_NOT_EXPR
, type
,
10143 fold_convert (type
, TREE_OPERAND (arg0
, 0)));
10145 /* Convert -1 - A to ~A. */
10146 if (INTEGRAL_TYPE_P (type
)
10147 && integer_all_onesp (arg0
))
10148 return fold_build1 (BIT_NOT_EXPR
, type
, op1
);
10150 if (! FLOAT_TYPE_P (type
))
10152 if (integer_zerop (arg0
))
10153 return negate_expr (fold_convert (type
, arg1
));
10154 if (integer_zerop (arg1
))
10155 return non_lvalue (fold_convert (type
, arg0
));
10157 /* Fold A - (A & B) into ~B & A. */
10158 if (!TREE_SIDE_EFFECTS (arg0
)
10159 && TREE_CODE (arg1
) == BIT_AND_EXPR
)
10161 if (operand_equal_p (arg0
, TREE_OPERAND (arg1
, 1), 0))
10163 tree arg10
= fold_convert (type
, TREE_OPERAND (arg1
, 0));
10164 return fold_build2 (BIT_AND_EXPR
, type
,
10165 fold_build1 (BIT_NOT_EXPR
, type
, arg10
),
10166 fold_convert (type
, arg0
));
10168 if (operand_equal_p (arg0
, TREE_OPERAND (arg1
, 0), 0))
10170 tree arg11
= fold_convert (type
, TREE_OPERAND (arg1
, 1));
10171 return fold_build2 (BIT_AND_EXPR
, type
,
10172 fold_build1 (BIT_NOT_EXPR
, type
, arg11
),
10173 fold_convert (type
, arg0
));
10177 /* Fold (A & ~B) - (A & B) into (A ^ B) - B, where B is
10178 any power of 2 minus 1. */
10179 if (TREE_CODE (arg0
) == BIT_AND_EXPR
10180 && TREE_CODE (arg1
) == BIT_AND_EXPR
10181 && operand_equal_p (TREE_OPERAND (arg0
, 0),
10182 TREE_OPERAND (arg1
, 0), 0))
10184 tree mask0
= TREE_OPERAND (arg0
, 1);
10185 tree mask1
= TREE_OPERAND (arg1
, 1);
10186 tree tem
= fold_build1 (BIT_NOT_EXPR
, type
, mask0
);
10188 if (operand_equal_p (tem
, mask1
, 0))
10190 tem
= fold_build2 (BIT_XOR_EXPR
, type
,
10191 TREE_OPERAND (arg0
, 0), mask1
);
10192 return fold_build2 (MINUS_EXPR
, type
, tem
, mask1
);
10197 /* See if ARG1 is zero and X - ARG1 reduces to X. */
10198 else if (fold_real_zero_addition_p (TREE_TYPE (arg0
), arg1
, 1))
10199 return non_lvalue (fold_convert (type
, arg0
));
10201 /* (ARG0 - ARG1) is the same as (-ARG1 + ARG0). So check whether
10202 ARG0 is zero and X + ARG0 reduces to X, since that would mean
10203 (-ARG1 + ARG0) reduces to -ARG1. */
10204 else if (fold_real_zero_addition_p (TREE_TYPE (arg1
), arg0
, 0))
10205 return negate_expr (fold_convert (type
, arg1
));
10207 /* Fold __complex__ ( x, 0 ) - __complex__ ( 0, y ) to
10208 __complex__ ( x, -y ). This is not the same for SNaNs or if
10209 signed zeros are involved. */
10210 if (!HONOR_SNANS (TYPE_MODE (TREE_TYPE (arg0
)))
10211 && !HONOR_SIGNED_ZEROS (TYPE_MODE (TREE_TYPE (arg0
)))
10212 && COMPLEX_FLOAT_TYPE_P (TREE_TYPE (arg0
)))
10214 tree rtype
= TREE_TYPE (TREE_TYPE (arg0
));
10215 tree arg0r
= fold_unary (REALPART_EXPR
, rtype
, arg0
);
10216 tree arg0i
= fold_unary (IMAGPART_EXPR
, rtype
, arg0
);
10217 bool arg0rz
= false, arg0iz
= false;
10218 if ((arg0r
&& (arg0rz
= real_zerop (arg0r
)))
10219 || (arg0i
&& (arg0iz
= real_zerop (arg0i
))))
10221 tree arg1r
= fold_unary (REALPART_EXPR
, rtype
, arg1
);
10222 tree arg1i
= fold_unary (IMAGPART_EXPR
, rtype
, arg1
);
10223 if (arg0rz
&& arg1i
&& real_zerop (arg1i
))
10225 tree rp
= fold_build1 (NEGATE_EXPR
, rtype
,
10227 : build1 (REALPART_EXPR
, rtype
, arg1
));
10228 tree ip
= arg0i
? arg0i
10229 : build1 (IMAGPART_EXPR
, rtype
, arg0
);
10230 return fold_build2 (COMPLEX_EXPR
, type
, rp
, ip
);
10232 else if (arg0iz
&& arg1r
&& real_zerop (arg1r
))
10234 tree rp
= arg0r
? arg0r
10235 : build1 (REALPART_EXPR
, rtype
, arg0
);
10236 tree ip
= fold_build1 (NEGATE_EXPR
, rtype
,
10238 : build1 (IMAGPART_EXPR
, rtype
, arg1
));
10239 return fold_build2 (COMPLEX_EXPR
, type
, rp
, ip
);
10244 /* Fold &x - &x. This can happen from &x.foo - &x.
10245 This is unsafe for certain floats even in non-IEEE formats.
10246 In IEEE, it is unsafe because it does wrong for NaNs.
10247 Also note that operand_equal_p is always false if an operand
10250 if ((!FLOAT_TYPE_P (type
) || !HONOR_NANS (TYPE_MODE (type
)))
10251 && operand_equal_p (arg0
, arg1
, 0))
10252 return fold_convert (type
, integer_zero_node
);
10254 /* A - B -> A + (-B) if B is easily negatable. */
10255 if (negate_expr_p (arg1
)
10256 && ((FLOAT_TYPE_P (type
)
10257 /* Avoid this transformation if B is a positive REAL_CST. */
10258 && (TREE_CODE (arg1
) != REAL_CST
10259 || REAL_VALUE_NEGATIVE (TREE_REAL_CST (arg1
))))
10260 || INTEGRAL_TYPE_P (type
)))
10261 return fold_build2 (PLUS_EXPR
, type
,
10262 fold_convert (type
, arg0
),
10263 fold_convert (type
, negate_expr (arg1
)));
10265 /* Try folding difference of addresses. */
10267 HOST_WIDE_INT diff
;
10269 if ((TREE_CODE (arg0
) == ADDR_EXPR
10270 || TREE_CODE (arg1
) == ADDR_EXPR
)
10271 && ptr_difference_const (arg0
, arg1
, &diff
))
10272 return build_int_cst_type (type
, diff
);
10275 /* Fold &a[i] - &a[j] to i-j. */
10276 if (TREE_CODE (arg0
) == ADDR_EXPR
10277 && TREE_CODE (TREE_OPERAND (arg0
, 0)) == ARRAY_REF
10278 && TREE_CODE (arg1
) == ADDR_EXPR
10279 && TREE_CODE (TREE_OPERAND (arg1
, 0)) == ARRAY_REF
)
10281 tree aref0
= TREE_OPERAND (arg0
, 0);
10282 tree aref1
= TREE_OPERAND (arg1
, 0);
10283 if (operand_equal_p (TREE_OPERAND (aref0
, 0),
10284 TREE_OPERAND (aref1
, 0), 0))
10286 tree op0
= fold_convert (type
, TREE_OPERAND (aref0
, 1));
10287 tree op1
= fold_convert (type
, TREE_OPERAND (aref1
, 1));
10288 tree esz
= array_ref_element_size (aref0
);
10289 tree diff
= build2 (MINUS_EXPR
, type
, op0
, op1
);
10290 return fold_build2 (MULT_EXPR
, type
, diff
,
10291 fold_convert (type
, esz
));
10296 if (flag_unsafe_math_optimizations
10297 && (TREE_CODE (arg0
) == RDIV_EXPR
|| TREE_CODE (arg0
) == MULT_EXPR
)
10298 && (TREE_CODE (arg1
) == RDIV_EXPR
|| TREE_CODE (arg1
) == MULT_EXPR
)
10299 && (tem
= distribute_real_division (code
, type
, arg0
, arg1
)))
10302 /* Handle (A1 * C1) - (A2 * C2) with A1, A2 or C1, C2 being the
10303 same or one. Make sure type is not saturating.
10304 fold_plusminus_mult_expr will re-associate. */
10305 if ((TREE_CODE (arg0
) == MULT_EXPR
10306 || TREE_CODE (arg1
) == MULT_EXPR
)
10307 && !TYPE_SATURATING (type
)
10308 && (!FLOAT_TYPE_P (type
) || flag_associative_math
))
10310 tree tem
= fold_plusminus_mult_expr (code
, type
, arg0
, arg1
);
10318 /* (-A) * (-B) -> A * B */
10319 if (TREE_CODE (arg0
) == NEGATE_EXPR
&& negate_expr_p (arg1
))
10320 return fold_build2 (MULT_EXPR
, type
,
10321 fold_convert (type
, TREE_OPERAND (arg0
, 0)),
10322 fold_convert (type
, negate_expr (arg1
)));
10323 if (TREE_CODE (arg1
) == NEGATE_EXPR
&& negate_expr_p (arg0
))
10324 return fold_build2 (MULT_EXPR
, type
,
10325 fold_convert (type
, negate_expr (arg0
)),
10326 fold_convert (type
, TREE_OPERAND (arg1
, 0)));
10328 if (! FLOAT_TYPE_P (type
))
10330 if (integer_zerop (arg1
))
10331 return omit_one_operand (type
, arg1
, arg0
);
10332 if (integer_onep (arg1
))
10333 return non_lvalue (fold_convert (type
, arg0
));
10334 /* Transform x * -1 into -x. Make sure to do the negation
10335 on the original operand with conversions not stripped
10336 because we can only strip non-sign-changing conversions. */
10337 if (integer_all_onesp (arg1
))
10338 return fold_convert (type
, negate_expr (op0
));
10339 /* Transform x * -C into -x * C if x is easily negatable. */
10340 if (TREE_CODE (arg1
) == INTEGER_CST
10341 && tree_int_cst_sgn (arg1
) == -1
10342 && negate_expr_p (arg0
)
10343 && (tem
= negate_expr (arg1
)) != arg1
10344 && !TREE_OVERFLOW (tem
))
10345 return fold_build2 (MULT_EXPR
, type
,
10346 negate_expr (arg0
), tem
);
10348 /* (a * (1 << b)) is (a << b) */
10349 if (TREE_CODE (arg1
) == LSHIFT_EXPR
10350 && integer_onep (TREE_OPERAND (arg1
, 0)))
10351 return fold_build2 (LSHIFT_EXPR
, type
, arg0
,
10352 TREE_OPERAND (arg1
, 1));
10353 if (TREE_CODE (arg0
) == LSHIFT_EXPR
10354 && integer_onep (TREE_OPERAND (arg0
, 0)))
10355 return fold_build2 (LSHIFT_EXPR
, type
, arg1
,
10356 TREE_OPERAND (arg0
, 1));
10358 strict_overflow_p
= false;
10359 if (TREE_CODE (arg1
) == INTEGER_CST
10360 && 0 != (tem
= extract_muldiv (op0
,
10361 fold_convert (type
, arg1
),
10363 &strict_overflow_p
)))
10365 if (strict_overflow_p
)
10366 fold_overflow_warning (("assuming signed overflow does not "
10367 "occur when simplifying "
10369 WARN_STRICT_OVERFLOW_MISC
);
10370 return fold_convert (type
, tem
);
10373 /* Optimize z * conj(z) for integer complex numbers. */
10374 if (TREE_CODE (arg0
) == CONJ_EXPR
10375 && operand_equal_p (TREE_OPERAND (arg0
, 0), arg1
, 0))
10376 return fold_mult_zconjz (type
, arg1
);
10377 if (TREE_CODE (arg1
) == CONJ_EXPR
10378 && operand_equal_p (arg0
, TREE_OPERAND (arg1
, 0), 0))
10379 return fold_mult_zconjz (type
, arg0
);
10383 /* Maybe fold x * 0 to 0. The expressions aren't the same
10384 when x is NaN, since x * 0 is also NaN. Nor are they the
10385 same in modes with signed zeros, since multiplying a
10386 negative value by 0 gives -0, not +0. */
10387 if (!HONOR_NANS (TYPE_MODE (TREE_TYPE (arg0
)))
10388 && !HONOR_SIGNED_ZEROS (TYPE_MODE (TREE_TYPE (arg0
)))
10389 && real_zerop (arg1
))
10390 return omit_one_operand (type
, arg1
, arg0
);
10391 /* In IEEE floating point, x*1 is not equivalent to x for snans. */
10392 if (!HONOR_SNANS (TYPE_MODE (TREE_TYPE (arg0
)))
10393 && real_onep (arg1
))
10394 return non_lvalue (fold_convert (type
, arg0
));
10396 /* Transform x * -1.0 into -x. */
10397 if (!HONOR_SNANS (TYPE_MODE (TREE_TYPE (arg0
)))
10398 && real_minus_onep (arg1
))
10399 return fold_convert (type
, negate_expr (arg0
));
10401 /* Convert (C1/X)*C2 into (C1*C2)/X. This transformation may change
10402 the result for floating point types due to rounding so it is applied
10403 only if -fassociative-math was specify. */
10404 if (flag_associative_math
10405 && TREE_CODE (arg0
) == RDIV_EXPR
10406 && TREE_CODE (arg1
) == REAL_CST
10407 && TREE_CODE (TREE_OPERAND (arg0
, 0)) == REAL_CST
)
10409 tree tem
= const_binop (MULT_EXPR
, TREE_OPERAND (arg0
, 0),
10412 return fold_build2 (RDIV_EXPR
, type
, tem
,
10413 TREE_OPERAND (arg0
, 1));
10416 /* Strip sign operations from X in X*X, i.e. -Y*-Y -> Y*Y. */
10417 if (operand_equal_p (arg0
, arg1
, 0))
10419 tree tem
= fold_strip_sign_ops (arg0
);
10420 if (tem
!= NULL_TREE
)
10422 tem
= fold_convert (type
, tem
);
10423 return fold_build2 (MULT_EXPR
, type
, tem
, tem
);
10427 /* Fold z * +-I to __complex__ (-+__imag z, +-__real z).
10428 This is not the same for NaNs or if signed zeros are
10430 if (!HONOR_NANS (TYPE_MODE (TREE_TYPE (arg0
)))
10431 && !HONOR_SIGNED_ZEROS (TYPE_MODE (TREE_TYPE (arg0
)))
10432 && COMPLEX_FLOAT_TYPE_P (TREE_TYPE (arg0
))
10433 && TREE_CODE (arg1
) == COMPLEX_CST
10434 && real_zerop (TREE_REALPART (arg1
)))
10436 tree rtype
= TREE_TYPE (TREE_TYPE (arg0
));
10437 if (real_onep (TREE_IMAGPART (arg1
)))
10438 return fold_build2 (COMPLEX_EXPR
, type
,
10439 negate_expr (fold_build1 (IMAGPART_EXPR
,
10441 fold_build1 (REALPART_EXPR
, rtype
, arg0
));
10442 else if (real_minus_onep (TREE_IMAGPART (arg1
)))
10443 return fold_build2 (COMPLEX_EXPR
, type
,
10444 fold_build1 (IMAGPART_EXPR
, rtype
, arg0
),
10445 negate_expr (fold_build1 (REALPART_EXPR
,
10449 /* Optimize z * conj(z) for floating point complex numbers.
10450 Guarded by flag_unsafe_math_optimizations as non-finite
10451 imaginary components don't produce scalar results. */
10452 if (flag_unsafe_math_optimizations
10453 && TREE_CODE (arg0
) == CONJ_EXPR
10454 && operand_equal_p (TREE_OPERAND (arg0
, 0), arg1
, 0))
10455 return fold_mult_zconjz (type
, arg1
);
10456 if (flag_unsafe_math_optimizations
10457 && TREE_CODE (arg1
) == CONJ_EXPR
10458 && operand_equal_p (arg0
, TREE_OPERAND (arg1
, 0), 0))
10459 return fold_mult_zconjz (type
, arg0
);
10461 if (flag_unsafe_math_optimizations
)
10463 enum built_in_function fcode0
= builtin_mathfn_code (arg0
);
10464 enum built_in_function fcode1
= builtin_mathfn_code (arg1
);
10466 /* Optimizations of root(...)*root(...). */
10467 if (fcode0
== fcode1
&& BUILTIN_ROOT_P (fcode0
))
10470 tree arg00
= CALL_EXPR_ARG (arg0
, 0);
10471 tree arg10
= CALL_EXPR_ARG (arg1
, 0);
10473 /* Optimize sqrt(x)*sqrt(x) as x. */
10474 if (BUILTIN_SQRT_P (fcode0
)
10475 && operand_equal_p (arg00
, arg10
, 0)
10476 && ! HONOR_SNANS (TYPE_MODE (type
)))
10479 /* Optimize root(x)*root(y) as root(x*y). */
10480 rootfn
= TREE_OPERAND (CALL_EXPR_FN (arg0
), 0);
10481 arg
= fold_build2 (MULT_EXPR
, type
, arg00
, arg10
);
10482 return build_call_expr (rootfn
, 1, arg
);
10485 /* Optimize expN(x)*expN(y) as expN(x+y). */
10486 if (fcode0
== fcode1
&& BUILTIN_EXPONENT_P (fcode0
))
10488 tree expfn
= TREE_OPERAND (CALL_EXPR_FN (arg0
), 0);
10489 tree arg
= fold_build2 (PLUS_EXPR
, type
,
10490 CALL_EXPR_ARG (arg0
, 0),
10491 CALL_EXPR_ARG (arg1
, 0));
10492 return build_call_expr (expfn
, 1, arg
);
10495 /* Optimizations of pow(...)*pow(...). */
10496 if ((fcode0
== BUILT_IN_POW
&& fcode1
== BUILT_IN_POW
)
10497 || (fcode0
== BUILT_IN_POWF
&& fcode1
== BUILT_IN_POWF
)
10498 || (fcode0
== BUILT_IN_POWL
&& fcode1
== BUILT_IN_POWL
))
10500 tree arg00
= CALL_EXPR_ARG (arg0
, 0);
10501 tree arg01
= CALL_EXPR_ARG (arg0
, 1);
10502 tree arg10
= CALL_EXPR_ARG (arg1
, 0);
10503 tree arg11
= CALL_EXPR_ARG (arg1
, 1);
10505 /* Optimize pow(x,y)*pow(z,y) as pow(x*z,y). */
10506 if (operand_equal_p (arg01
, arg11
, 0))
10508 tree powfn
= TREE_OPERAND (CALL_EXPR_FN (arg0
), 0);
10509 tree arg
= fold_build2 (MULT_EXPR
, type
, arg00
, arg10
);
10510 return build_call_expr (powfn
, 2, arg
, arg01
);
10513 /* Optimize pow(x,y)*pow(x,z) as pow(x,y+z). */
10514 if (operand_equal_p (arg00
, arg10
, 0))
10516 tree powfn
= TREE_OPERAND (CALL_EXPR_FN (arg0
), 0);
10517 tree arg
= fold_build2 (PLUS_EXPR
, type
, arg01
, arg11
);
10518 return build_call_expr (powfn
, 2, arg00
, arg
);
10522 /* Optimize tan(x)*cos(x) as sin(x). */
10523 if (((fcode0
== BUILT_IN_TAN
&& fcode1
== BUILT_IN_COS
)
10524 || (fcode0
== BUILT_IN_TANF
&& fcode1
== BUILT_IN_COSF
)
10525 || (fcode0
== BUILT_IN_TANL
&& fcode1
== BUILT_IN_COSL
)
10526 || (fcode0
== BUILT_IN_COS
&& fcode1
== BUILT_IN_TAN
)
10527 || (fcode0
== BUILT_IN_COSF
&& fcode1
== BUILT_IN_TANF
)
10528 || (fcode0
== BUILT_IN_COSL
&& fcode1
== BUILT_IN_TANL
))
10529 && operand_equal_p (CALL_EXPR_ARG (arg0
, 0),
10530 CALL_EXPR_ARG (arg1
, 0), 0))
10532 tree sinfn
= mathfn_built_in (type
, BUILT_IN_SIN
);
10534 if (sinfn
!= NULL_TREE
)
10535 return build_call_expr (sinfn
, 1, CALL_EXPR_ARG (arg0
, 0));
10538 /* Optimize x*pow(x,c) as pow(x,c+1). */
10539 if (fcode1
== BUILT_IN_POW
10540 || fcode1
== BUILT_IN_POWF
10541 || fcode1
== BUILT_IN_POWL
)
10543 tree arg10
= CALL_EXPR_ARG (arg1
, 0);
10544 tree arg11
= CALL_EXPR_ARG (arg1
, 1);
10545 if (TREE_CODE (arg11
) == REAL_CST
10546 && !TREE_OVERFLOW (arg11
)
10547 && operand_equal_p (arg0
, arg10
, 0))
10549 tree powfn
= TREE_OPERAND (CALL_EXPR_FN (arg1
), 0);
10553 c
= TREE_REAL_CST (arg11
);
10554 real_arithmetic (&c
, PLUS_EXPR
, &c
, &dconst1
);
10555 arg
= build_real (type
, c
);
10556 return build_call_expr (powfn
, 2, arg0
, arg
);
10560 /* Optimize pow(x,c)*x as pow(x,c+1). */
10561 if (fcode0
== BUILT_IN_POW
10562 || fcode0
== BUILT_IN_POWF
10563 || fcode0
== BUILT_IN_POWL
)
10565 tree arg00
= CALL_EXPR_ARG (arg0
, 0);
10566 tree arg01
= CALL_EXPR_ARG (arg0
, 1);
10567 if (TREE_CODE (arg01
) == REAL_CST
10568 && !TREE_OVERFLOW (arg01
)
10569 && operand_equal_p (arg1
, arg00
, 0))
10571 tree powfn
= TREE_OPERAND (CALL_EXPR_FN (arg0
), 0);
10575 c
= TREE_REAL_CST (arg01
);
10576 real_arithmetic (&c
, PLUS_EXPR
, &c
, &dconst1
);
10577 arg
= build_real (type
, c
);
10578 return build_call_expr (powfn
, 2, arg1
, arg
);
10582 /* Optimize x*x as pow(x,2.0), which is expanded as x*x. */
10583 if (! optimize_size
10584 && operand_equal_p (arg0
, arg1
, 0))
10586 tree powfn
= mathfn_built_in (type
, BUILT_IN_POW
);
10590 tree arg
= build_real (type
, dconst2
);
10591 return build_call_expr (powfn
, 2, arg0
, arg
);
10600 if (integer_all_onesp (arg1
))
10601 return omit_one_operand (type
, arg1
, arg0
);
10602 if (integer_zerop (arg1
))
10603 return non_lvalue (fold_convert (type
, arg0
));
10604 if (operand_equal_p (arg0
, arg1
, 0))
10605 return non_lvalue (fold_convert (type
, arg0
));
10607 /* ~X | X is -1. */
10608 if (TREE_CODE (arg0
) == BIT_NOT_EXPR
10609 && operand_equal_p (TREE_OPERAND (arg0
, 0), arg1
, 0))
10611 t1
= fold_convert (type
, integer_zero_node
);
10612 t1
= fold_unary (BIT_NOT_EXPR
, type
, t1
);
10613 return omit_one_operand (type
, t1
, arg1
);
10616 /* X | ~X is -1. */
10617 if (TREE_CODE (arg1
) == BIT_NOT_EXPR
10618 && operand_equal_p (arg0
, TREE_OPERAND (arg1
, 0), 0))
10620 t1
= fold_convert (type
, integer_zero_node
);
10621 t1
= fold_unary (BIT_NOT_EXPR
, type
, t1
);
10622 return omit_one_operand (type
, t1
, arg0
);
10625 /* Canonicalize (X & C1) | C2. */
10626 if (TREE_CODE (arg0
) == BIT_AND_EXPR
10627 && TREE_CODE (arg1
) == INTEGER_CST
10628 && TREE_CODE (TREE_OPERAND (arg0
, 1)) == INTEGER_CST
)
10630 unsigned HOST_WIDE_INT hi1
, lo1
, hi2
, lo2
, mlo
, mhi
;
10631 int width
= TYPE_PRECISION (type
);
10632 hi1
= TREE_INT_CST_HIGH (TREE_OPERAND (arg0
, 1));
10633 lo1
= TREE_INT_CST_LOW (TREE_OPERAND (arg0
, 1));
10634 hi2
= TREE_INT_CST_HIGH (arg1
);
10635 lo2
= TREE_INT_CST_LOW (arg1
);
10637 /* If (C1&C2) == C1, then (X&C1)|C2 becomes (X,C2). */
10638 if ((hi1
& hi2
) == hi1
&& (lo1
& lo2
) == lo1
)
10639 return omit_one_operand (type
, arg1
, TREE_OPERAND (arg0
, 0));
10641 if (width
> HOST_BITS_PER_WIDE_INT
)
10643 mhi
= (unsigned HOST_WIDE_INT
) -1
10644 >> (2 * HOST_BITS_PER_WIDE_INT
- width
);
10650 mlo
= (unsigned HOST_WIDE_INT
) -1
10651 >> (HOST_BITS_PER_WIDE_INT
- width
);
10654 /* If (C1|C2) == ~0 then (X&C1)|C2 becomes X|C2. */
10655 if ((~(hi1
| hi2
) & mhi
) == 0 && (~(lo1
| lo2
) & mlo
) == 0)
10656 return fold_build2 (BIT_IOR_EXPR
, type
,
10657 TREE_OPERAND (arg0
, 0), arg1
);
10659 /* Minimize the number of bits set in C1, i.e. C1 := C1 & ~C2. */
10662 if ((hi1
& ~hi2
) != hi1
|| (lo1
& ~lo2
) != lo1
)
10663 return fold_build2 (BIT_IOR_EXPR
, type
,
10664 fold_build2 (BIT_AND_EXPR
, type
,
10665 TREE_OPERAND (arg0
, 0),
10666 build_int_cst_wide (type
,
10672 /* (X & Y) | Y is (X, Y). */
10673 if (TREE_CODE (arg0
) == BIT_AND_EXPR
10674 && operand_equal_p (TREE_OPERAND (arg0
, 1), arg1
, 0))
10675 return omit_one_operand (type
, arg1
, TREE_OPERAND (arg0
, 0));
10676 /* (X & Y) | X is (Y, X). */
10677 if (TREE_CODE (arg0
) == BIT_AND_EXPR
10678 && operand_equal_p (TREE_OPERAND (arg0
, 0), arg1
, 0)
10679 && reorder_operands_p (TREE_OPERAND (arg0
, 1), arg1
))
10680 return omit_one_operand (type
, arg1
, TREE_OPERAND (arg0
, 1));
10681 /* X | (X & Y) is (Y, X). */
10682 if (TREE_CODE (arg1
) == BIT_AND_EXPR
10683 && operand_equal_p (arg0
, TREE_OPERAND (arg1
, 0), 0)
10684 && reorder_operands_p (arg0
, TREE_OPERAND (arg1
, 1)))
10685 return omit_one_operand (type
, arg0
, TREE_OPERAND (arg1
, 1));
10686 /* X | (Y & X) is (Y, X). */
10687 if (TREE_CODE (arg1
) == BIT_AND_EXPR
10688 && operand_equal_p (arg0
, TREE_OPERAND (arg1
, 1), 0)
10689 && reorder_operands_p (arg0
, TREE_OPERAND (arg1
, 0)))
10690 return omit_one_operand (type
, arg0
, TREE_OPERAND (arg1
, 0));
10692 t1
= distribute_bit_expr (code
, type
, arg0
, arg1
);
10693 if (t1
!= NULL_TREE
)
10696 /* Convert (or (not arg0) (not arg1)) to (not (and (arg0) (arg1))).
10698 This results in more efficient code for machines without a NAND
10699 instruction. Combine will canonicalize to the first form
10700 which will allow use of NAND instructions provided by the
10701 backend if they exist. */
10702 if (TREE_CODE (arg0
) == BIT_NOT_EXPR
10703 && TREE_CODE (arg1
) == BIT_NOT_EXPR
)
10705 return fold_build1 (BIT_NOT_EXPR
, type
,
10706 build2 (BIT_AND_EXPR
, type
,
10707 TREE_OPERAND (arg0
, 0),
10708 TREE_OPERAND (arg1
, 0)));
10711 /* See if this can be simplified into a rotate first. If that
10712 is unsuccessful continue in the association code. */
10716 if (integer_zerop (arg1
))
10717 return non_lvalue (fold_convert (type
, arg0
));
10718 if (integer_all_onesp (arg1
))
10719 return fold_build1 (BIT_NOT_EXPR
, type
, op0
);
10720 if (operand_equal_p (arg0
, arg1
, 0))
10721 return omit_one_operand (type
, integer_zero_node
, arg0
);
10723 /* ~X ^ X is -1. */
10724 if (TREE_CODE (arg0
) == BIT_NOT_EXPR
10725 && operand_equal_p (TREE_OPERAND (arg0
, 0), arg1
, 0))
10727 t1
= fold_convert (type
, integer_zero_node
);
10728 t1
= fold_unary (BIT_NOT_EXPR
, type
, t1
);
10729 return omit_one_operand (type
, t1
, arg1
);
10732 /* X ^ ~X is -1. */
10733 if (TREE_CODE (arg1
) == BIT_NOT_EXPR
10734 && operand_equal_p (arg0
, TREE_OPERAND (arg1
, 0), 0))
10736 t1
= fold_convert (type
, integer_zero_node
);
10737 t1
= fold_unary (BIT_NOT_EXPR
, type
, t1
);
10738 return omit_one_operand (type
, t1
, arg0
);
10741 /* If we are XORing two BIT_AND_EXPR's, both of which are and'ing
10742 with a constant, and the two constants have no bits in common,
10743 we should treat this as a BIT_IOR_EXPR since this may produce more
10744 simplifications. */
10745 if (TREE_CODE (arg0
) == BIT_AND_EXPR
10746 && TREE_CODE (arg1
) == BIT_AND_EXPR
10747 && TREE_CODE (TREE_OPERAND (arg0
, 1)) == INTEGER_CST
10748 && TREE_CODE (TREE_OPERAND (arg1
, 1)) == INTEGER_CST
10749 && integer_zerop (const_binop (BIT_AND_EXPR
,
10750 TREE_OPERAND (arg0
, 1),
10751 TREE_OPERAND (arg1
, 1), 0)))
10753 code
= BIT_IOR_EXPR
;
10757 /* (X | Y) ^ X -> Y & ~ X*/
10758 if (TREE_CODE (arg0
) == BIT_IOR_EXPR
10759 && operand_equal_p (TREE_OPERAND (arg0
, 0), arg1
, 0))
10761 tree t2
= TREE_OPERAND (arg0
, 1);
10762 t1
= fold_build1 (BIT_NOT_EXPR
, TREE_TYPE (arg1
),
10764 t1
= fold_build2 (BIT_AND_EXPR
, type
, fold_convert (type
, t2
),
10765 fold_convert (type
, t1
));
10769 /* (Y | X) ^ X -> Y & ~ X*/
10770 if (TREE_CODE (arg0
) == BIT_IOR_EXPR
10771 && operand_equal_p (TREE_OPERAND (arg0
, 1), arg1
, 0))
10773 tree t2
= TREE_OPERAND (arg0
, 0);
10774 t1
= fold_build1 (BIT_NOT_EXPR
, TREE_TYPE (arg1
),
10776 t1
= fold_build2 (BIT_AND_EXPR
, type
, fold_convert (type
, t2
),
10777 fold_convert (type
, t1
));
10781 /* X ^ (X | Y) -> Y & ~ X*/
10782 if (TREE_CODE (arg1
) == BIT_IOR_EXPR
10783 && operand_equal_p (TREE_OPERAND (arg1
, 0), arg0
, 0))
10785 tree t2
= TREE_OPERAND (arg1
, 1);
10786 t1
= fold_build1 (BIT_NOT_EXPR
, TREE_TYPE (arg0
),
10788 t1
= fold_build2 (BIT_AND_EXPR
, type
, fold_convert (type
, t2
),
10789 fold_convert (type
, t1
));
10793 /* X ^ (Y | X) -> Y & ~ X*/
10794 if (TREE_CODE (arg1
) == BIT_IOR_EXPR
10795 && operand_equal_p (TREE_OPERAND (arg1
, 1), arg0
, 0))
10797 tree t2
= TREE_OPERAND (arg1
, 0);
10798 t1
= fold_build1 (BIT_NOT_EXPR
, TREE_TYPE (arg0
),
10800 t1
= fold_build2 (BIT_AND_EXPR
, type
, fold_convert (type
, t2
),
10801 fold_convert (type
, t1
));
10805 /* Convert ~X ^ ~Y to X ^ Y. */
10806 if (TREE_CODE (arg0
) == BIT_NOT_EXPR
10807 && TREE_CODE (arg1
) == BIT_NOT_EXPR
)
10808 return fold_build2 (code
, type
,
10809 fold_convert (type
, TREE_OPERAND (arg0
, 0)),
10810 fold_convert (type
, TREE_OPERAND (arg1
, 0)));
10812 /* Convert ~X ^ C to X ^ ~C. */
10813 if (TREE_CODE (arg0
) == BIT_NOT_EXPR
10814 && TREE_CODE (arg1
) == INTEGER_CST
)
10815 return fold_build2 (code
, type
,
10816 fold_convert (type
, TREE_OPERAND (arg0
, 0)),
10817 fold_build1 (BIT_NOT_EXPR
, type
, arg1
));
10819 /* Fold (X & 1) ^ 1 as (X & 1) == 0. */
10820 if (TREE_CODE (arg0
) == BIT_AND_EXPR
10821 && integer_onep (TREE_OPERAND (arg0
, 1))
10822 && integer_onep (arg1
))
10823 return fold_build2 (EQ_EXPR
, type
, arg0
,
10824 build_int_cst (TREE_TYPE (arg0
), 0));
10826 /* Fold (X & Y) ^ Y as ~X & Y. */
10827 if (TREE_CODE (arg0
) == BIT_AND_EXPR
10828 && operand_equal_p (TREE_OPERAND (arg0
, 1), arg1
, 0))
10830 tem
= fold_convert (type
, TREE_OPERAND (arg0
, 0));
10831 return fold_build2 (BIT_AND_EXPR
, type
,
10832 fold_build1 (BIT_NOT_EXPR
, type
, tem
),
10833 fold_convert (type
, arg1
));
10835 /* Fold (X & Y) ^ X as ~Y & X. */
10836 if (TREE_CODE (arg0
) == BIT_AND_EXPR
10837 && operand_equal_p (TREE_OPERAND (arg0
, 0), arg1
, 0)
10838 && reorder_operands_p (TREE_OPERAND (arg0
, 1), arg1
))
10840 tem
= fold_convert (type
, TREE_OPERAND (arg0
, 1));
10841 return fold_build2 (BIT_AND_EXPR
, type
,
10842 fold_build1 (BIT_NOT_EXPR
, type
, tem
),
10843 fold_convert (type
, arg1
));
10845 /* Fold X ^ (X & Y) as X & ~Y. */
10846 if (TREE_CODE (arg1
) == BIT_AND_EXPR
10847 && operand_equal_p (arg0
, TREE_OPERAND (arg1
, 0), 0))
10849 tem
= fold_convert (type
, TREE_OPERAND (arg1
, 1));
10850 return fold_build2 (BIT_AND_EXPR
, type
,
10851 fold_convert (type
, arg0
),
10852 fold_build1 (BIT_NOT_EXPR
, type
, tem
));
10854 /* Fold X ^ (Y & X) as ~Y & X. */
10855 if (TREE_CODE (arg1
) == BIT_AND_EXPR
10856 && operand_equal_p (arg0
, TREE_OPERAND (arg1
, 1), 0)
10857 && reorder_operands_p (arg0
, TREE_OPERAND (arg1
, 0)))
10859 tem
= fold_convert (type
, TREE_OPERAND (arg1
, 0));
10860 return fold_build2 (BIT_AND_EXPR
, type
,
10861 fold_build1 (BIT_NOT_EXPR
, type
, tem
),
10862 fold_convert (type
, arg0
));
10865 /* See if this can be simplified into a rotate first. If that
10866 is unsuccessful continue in the association code. */
10870 if (integer_all_onesp (arg1
))
10871 return non_lvalue (fold_convert (type
, arg0
));
10872 if (integer_zerop (arg1
))
10873 return omit_one_operand (type
, arg1
, arg0
);
10874 if (operand_equal_p (arg0
, arg1
, 0))
10875 return non_lvalue (fold_convert (type
, arg0
));
10877 /* ~X & X is always zero. */
10878 if (TREE_CODE (arg0
) == BIT_NOT_EXPR
10879 && operand_equal_p (TREE_OPERAND (arg0
, 0), arg1
, 0))
10880 return omit_one_operand (type
, integer_zero_node
, arg1
);
10882 /* X & ~X is always zero. */
10883 if (TREE_CODE (arg1
) == BIT_NOT_EXPR
10884 && operand_equal_p (arg0
, TREE_OPERAND (arg1
, 0), 0))
10885 return omit_one_operand (type
, integer_zero_node
, arg0
);
10887 /* Canonicalize (X | C1) & C2 as (X & C2) | (C1 & C2). */
10888 if (TREE_CODE (arg0
) == BIT_IOR_EXPR
10889 && TREE_CODE (arg1
) == INTEGER_CST
10890 && TREE_CODE (TREE_OPERAND (arg0
, 1)) == INTEGER_CST
)
10891 return fold_build2 (BIT_IOR_EXPR
, type
,
10892 fold_build2 (BIT_AND_EXPR
, type
,
10893 TREE_OPERAND (arg0
, 0), arg1
),
10894 fold_build2 (BIT_AND_EXPR
, type
,
10895 TREE_OPERAND (arg0
, 1), arg1
));
10897 /* (X | Y) & Y is (X, Y). */
10898 if (TREE_CODE (arg0
) == BIT_IOR_EXPR
10899 && operand_equal_p (TREE_OPERAND (arg0
, 1), arg1
, 0))
10900 return omit_one_operand (type
, arg1
, TREE_OPERAND (arg0
, 0));
10901 /* (X | Y) & X is (Y, X). */
10902 if (TREE_CODE (arg0
) == BIT_IOR_EXPR
10903 && operand_equal_p (TREE_OPERAND (arg0
, 0), arg1
, 0)
10904 && reorder_operands_p (TREE_OPERAND (arg0
, 1), arg1
))
10905 return omit_one_operand (type
, arg1
, TREE_OPERAND (arg0
, 1));
10906 /* X & (X | Y) is (Y, X). */
10907 if (TREE_CODE (arg1
) == BIT_IOR_EXPR
10908 && operand_equal_p (arg0
, TREE_OPERAND (arg1
, 0), 0)
10909 && reorder_operands_p (arg0
, TREE_OPERAND (arg1
, 1)))
10910 return omit_one_operand (type
, arg0
, TREE_OPERAND (arg1
, 1));
10911 /* X & (Y | X) is (Y, X). */
10912 if (TREE_CODE (arg1
) == BIT_IOR_EXPR
10913 && operand_equal_p (arg0
, TREE_OPERAND (arg1
, 1), 0)
10914 && reorder_operands_p (arg0
, TREE_OPERAND (arg1
, 0)))
10915 return omit_one_operand (type
, arg0
, TREE_OPERAND (arg1
, 0));
10917 /* Fold (X ^ 1) & 1 as (X & 1) == 0. */
10918 if (TREE_CODE (arg0
) == BIT_XOR_EXPR
10919 && integer_onep (TREE_OPERAND (arg0
, 1))
10920 && integer_onep (arg1
))
10922 tem
= TREE_OPERAND (arg0
, 0);
10923 return fold_build2 (EQ_EXPR
, type
,
10924 fold_build2 (BIT_AND_EXPR
, TREE_TYPE (tem
), tem
,
10925 build_int_cst (TREE_TYPE (tem
), 1)),
10926 build_int_cst (TREE_TYPE (tem
), 0));
10928 /* Fold ~X & 1 as (X & 1) == 0. */
10929 if (TREE_CODE (arg0
) == BIT_NOT_EXPR
10930 && integer_onep (arg1
))
10932 tem
= TREE_OPERAND (arg0
, 0);
10933 return fold_build2 (EQ_EXPR
, type
,
10934 fold_build2 (BIT_AND_EXPR
, TREE_TYPE (tem
), tem
,
10935 build_int_cst (TREE_TYPE (tem
), 1)),
10936 build_int_cst (TREE_TYPE (tem
), 0));
10939 /* Fold (X ^ Y) & Y as ~X & Y. */
10940 if (TREE_CODE (arg0
) == BIT_XOR_EXPR
10941 && operand_equal_p (TREE_OPERAND (arg0
, 1), arg1
, 0))
10943 tem
= fold_convert (type
, TREE_OPERAND (arg0
, 0));
10944 return fold_build2 (BIT_AND_EXPR
, type
,
10945 fold_build1 (BIT_NOT_EXPR
, type
, tem
),
10946 fold_convert (type
, arg1
));
10948 /* Fold (X ^ Y) & X as ~Y & X. */
10949 if (TREE_CODE (arg0
) == BIT_XOR_EXPR
10950 && operand_equal_p (TREE_OPERAND (arg0
, 0), arg1
, 0)
10951 && reorder_operands_p (TREE_OPERAND (arg0
, 1), arg1
))
10953 tem
= fold_convert (type
, TREE_OPERAND (arg0
, 1));
10954 return fold_build2 (BIT_AND_EXPR
, type
,
10955 fold_build1 (BIT_NOT_EXPR
, type
, tem
),
10956 fold_convert (type
, arg1
));
10958 /* Fold X & (X ^ Y) as X & ~Y. */
10959 if (TREE_CODE (arg1
) == BIT_XOR_EXPR
10960 && operand_equal_p (arg0
, TREE_OPERAND (arg1
, 0), 0))
10962 tem
= fold_convert (type
, TREE_OPERAND (arg1
, 1));
10963 return fold_build2 (BIT_AND_EXPR
, type
,
10964 fold_convert (type
, arg0
),
10965 fold_build1 (BIT_NOT_EXPR
, type
, tem
));
10967 /* Fold X & (Y ^ X) as ~Y & X. */
10968 if (TREE_CODE (arg1
) == BIT_XOR_EXPR
10969 && operand_equal_p (arg0
, TREE_OPERAND (arg1
, 1), 0)
10970 && reorder_operands_p (arg0
, TREE_OPERAND (arg1
, 0)))
10972 tem
= fold_convert (type
, TREE_OPERAND (arg1
, 0));
10973 return fold_build2 (BIT_AND_EXPR
, type
,
10974 fold_build1 (BIT_NOT_EXPR
, type
, tem
),
10975 fold_convert (type
, arg0
));
10978 t1
= distribute_bit_expr (code
, type
, arg0
, arg1
);
10979 if (t1
!= NULL_TREE
)
10981 /* Simplify ((int)c & 0377) into (int)c, if c is unsigned char. */
10982 if (TREE_CODE (arg1
) == INTEGER_CST
&& TREE_CODE (arg0
) == NOP_EXPR
10983 && TYPE_UNSIGNED (TREE_TYPE (TREE_OPERAND (arg0
, 0))))
10986 = TYPE_PRECISION (TREE_TYPE (TREE_OPERAND (arg0
, 0)));
10988 if (prec
< BITS_PER_WORD
&& prec
< HOST_BITS_PER_WIDE_INT
10989 && (~TREE_INT_CST_LOW (arg1
)
10990 & (((HOST_WIDE_INT
) 1 << prec
) - 1)) == 0)
10991 return fold_convert (type
, TREE_OPERAND (arg0
, 0));
10994 /* Convert (and (not arg0) (not arg1)) to (not (or (arg0) (arg1))).
10996 This results in more efficient code for machines without a NOR
10997 instruction. Combine will canonicalize to the first form
10998 which will allow use of NOR instructions provided by the
10999 backend if they exist. */
11000 if (TREE_CODE (arg0
) == BIT_NOT_EXPR
11001 && TREE_CODE (arg1
) == BIT_NOT_EXPR
)
11003 return fold_build1 (BIT_NOT_EXPR
, type
,
11004 build2 (BIT_IOR_EXPR
, type
,
11005 TREE_OPERAND (arg0
, 0),
11006 TREE_OPERAND (arg1
, 0)));
11009 /* If arg0 is derived from the address of an object or function, we may
11010 be able to fold this expression using the object or function's
11012 if (POINTER_TYPE_P (TREE_TYPE (arg0
)) && host_integerp (arg1
, 1))
11014 unsigned HOST_WIDE_INT modulus
, residue
;
11015 unsigned HOST_WIDE_INT low
= TREE_INT_CST_LOW (arg1
);
11017 modulus
= get_pointer_modulus_and_residue (arg0
, &residue
);
11019 /* This works because modulus is a power of 2. If this weren't the
11020 case, we'd have to replace it by its greatest power-of-2
11021 divisor: modulus & -modulus. */
11023 return build_int_cst (type
, residue
& low
);
11029 /* Don't touch a floating-point divide by zero unless the mode
11030 of the constant can represent infinity. */
11031 if (TREE_CODE (arg1
) == REAL_CST
11032 && !MODE_HAS_INFINITIES (TYPE_MODE (TREE_TYPE (arg1
)))
11033 && real_zerop (arg1
))
11036 /* Optimize A / A to 1.0 if we don't care about
11037 NaNs or Infinities. Skip the transformation
11038 for non-real operands. */
11039 if (SCALAR_FLOAT_TYPE_P (TREE_TYPE (arg0
))
11040 && ! HONOR_NANS (TYPE_MODE (TREE_TYPE (arg0
)))
11041 && ! HONOR_INFINITIES (TYPE_MODE (TREE_TYPE (arg0
)))
11042 && operand_equal_p (arg0
, arg1
, 0))
11044 tree r
= build_real (TREE_TYPE (arg0
), dconst1
);
11046 return omit_two_operands (type
, r
, arg0
, arg1
);
11049 /* The complex version of the above A / A optimization. */
11050 if (COMPLEX_FLOAT_TYPE_P (TREE_TYPE (arg0
))
11051 && operand_equal_p (arg0
, arg1
, 0))
11053 tree elem_type
= TREE_TYPE (TREE_TYPE (arg0
));
11054 if (! HONOR_NANS (TYPE_MODE (elem_type
))
11055 && ! HONOR_INFINITIES (TYPE_MODE (elem_type
)))
11057 tree r
= build_real (elem_type
, dconst1
);
11058 /* omit_two_operands will call fold_convert for us. */
11059 return omit_two_operands (type
, r
, arg0
, arg1
);
11063 /* (-A) / (-B) -> A / B */
11064 if (TREE_CODE (arg0
) == NEGATE_EXPR
&& negate_expr_p (arg1
))
11065 return fold_build2 (RDIV_EXPR
, type
,
11066 TREE_OPERAND (arg0
, 0),
11067 negate_expr (arg1
));
11068 if (TREE_CODE (arg1
) == NEGATE_EXPR
&& negate_expr_p (arg0
))
11069 return fold_build2 (RDIV_EXPR
, type
,
11070 negate_expr (arg0
),
11071 TREE_OPERAND (arg1
, 0));
11073 /* In IEEE floating point, x/1 is not equivalent to x for snans. */
11074 if (!HONOR_SNANS (TYPE_MODE (TREE_TYPE (arg0
)))
11075 && real_onep (arg1
))
11076 return non_lvalue (fold_convert (type
, arg0
));
11078 /* In IEEE floating point, x/-1 is not equivalent to -x for snans. */
11079 if (!HONOR_SNANS (TYPE_MODE (TREE_TYPE (arg0
)))
11080 && real_minus_onep (arg1
))
11081 return non_lvalue (fold_convert (type
, negate_expr (arg0
)));
11083 /* If ARG1 is a constant, we can convert this to a multiply by the
11084 reciprocal. This does not have the same rounding properties,
11085 so only do this if -freciprocal-math. We can actually
11086 always safely do it if ARG1 is a power of two, but it's hard to
11087 tell if it is or not in a portable manner. */
11088 if (TREE_CODE (arg1
) == REAL_CST
)
11090 if (flag_reciprocal_math
11091 && 0 != (tem
= const_binop (code
, build_real (type
, dconst1
),
11093 return fold_build2 (MULT_EXPR
, type
, arg0
, tem
);
11094 /* Find the reciprocal if optimizing and the result is exact. */
11098 r
= TREE_REAL_CST (arg1
);
11099 if (exact_real_inverse (TYPE_MODE(TREE_TYPE(arg0
)), &r
))
11101 tem
= build_real (type
, r
);
11102 return fold_build2 (MULT_EXPR
, type
,
11103 fold_convert (type
, arg0
), tem
);
11107 /* Convert A/B/C to A/(B*C). */
11108 if (flag_reciprocal_math
11109 && TREE_CODE (arg0
) == RDIV_EXPR
)
11110 return fold_build2 (RDIV_EXPR
, type
, TREE_OPERAND (arg0
, 0),
11111 fold_build2 (MULT_EXPR
, type
,
11112 TREE_OPERAND (arg0
, 1), arg1
));
11114 /* Convert A/(B/C) to (A/B)*C. */
11115 if (flag_reciprocal_math
11116 && TREE_CODE (arg1
) == RDIV_EXPR
)
11117 return fold_build2 (MULT_EXPR
, type
,
11118 fold_build2 (RDIV_EXPR
, type
, arg0
,
11119 TREE_OPERAND (arg1
, 0)),
11120 TREE_OPERAND (arg1
, 1));
11122 /* Convert C1/(X*C2) into (C1/C2)/X. */
11123 if (flag_reciprocal_math
11124 && TREE_CODE (arg1
) == MULT_EXPR
11125 && TREE_CODE (arg0
) == REAL_CST
11126 && TREE_CODE (TREE_OPERAND (arg1
, 1)) == REAL_CST
)
11128 tree tem
= const_binop (RDIV_EXPR
, arg0
,
11129 TREE_OPERAND (arg1
, 1), 0);
11131 return fold_build2 (RDIV_EXPR
, type
, tem
,
11132 TREE_OPERAND (arg1
, 0));
11135 if (flag_unsafe_math_optimizations
)
11137 enum built_in_function fcode0
= builtin_mathfn_code (arg0
);
11138 enum built_in_function fcode1
= builtin_mathfn_code (arg1
);
11140 /* Optimize sin(x)/cos(x) as tan(x). */
11141 if (((fcode0
== BUILT_IN_SIN
&& fcode1
== BUILT_IN_COS
)
11142 || (fcode0
== BUILT_IN_SINF
&& fcode1
== BUILT_IN_COSF
)
11143 || (fcode0
== BUILT_IN_SINL
&& fcode1
== BUILT_IN_COSL
))
11144 && operand_equal_p (CALL_EXPR_ARG (arg0
, 0),
11145 CALL_EXPR_ARG (arg1
, 0), 0))
11147 tree tanfn
= mathfn_built_in (type
, BUILT_IN_TAN
);
11149 if (tanfn
!= NULL_TREE
)
11150 return build_call_expr (tanfn
, 1, CALL_EXPR_ARG (arg0
, 0));
11153 /* Optimize cos(x)/sin(x) as 1.0/tan(x). */
11154 if (((fcode0
== BUILT_IN_COS
&& fcode1
== BUILT_IN_SIN
)
11155 || (fcode0
== BUILT_IN_COSF
&& fcode1
== BUILT_IN_SINF
)
11156 || (fcode0
== BUILT_IN_COSL
&& fcode1
== BUILT_IN_SINL
))
11157 && operand_equal_p (CALL_EXPR_ARG (arg0
, 0),
11158 CALL_EXPR_ARG (arg1
, 0), 0))
11160 tree tanfn
= mathfn_built_in (type
, BUILT_IN_TAN
);
11162 if (tanfn
!= NULL_TREE
)
11164 tree tmp
= build_call_expr (tanfn
, 1, CALL_EXPR_ARG (arg0
, 0));
11165 return fold_build2 (RDIV_EXPR
, type
,
11166 build_real (type
, dconst1
), tmp
);
11170 /* Optimize sin(x)/tan(x) as cos(x) if we don't care about
11171 NaNs or Infinities. */
11172 if (((fcode0
== BUILT_IN_SIN
&& fcode1
== BUILT_IN_TAN
)
11173 || (fcode0
== BUILT_IN_SINF
&& fcode1
== BUILT_IN_TANF
)
11174 || (fcode0
== BUILT_IN_SINL
&& fcode1
== BUILT_IN_TANL
)))
11176 tree arg00
= CALL_EXPR_ARG (arg0
, 0);
11177 tree arg01
= CALL_EXPR_ARG (arg1
, 0);
11179 if (! HONOR_NANS (TYPE_MODE (TREE_TYPE (arg00
)))
11180 && ! HONOR_INFINITIES (TYPE_MODE (TREE_TYPE (arg00
)))
11181 && operand_equal_p (arg00
, arg01
, 0))
11183 tree cosfn
= mathfn_built_in (type
, BUILT_IN_COS
);
11185 if (cosfn
!= NULL_TREE
)
11186 return build_call_expr (cosfn
, 1, arg00
);
11190 /* Optimize tan(x)/sin(x) as 1.0/cos(x) if we don't care about
11191 NaNs or Infinities. */
11192 if (((fcode0
== BUILT_IN_TAN
&& fcode1
== BUILT_IN_SIN
)
11193 || (fcode0
== BUILT_IN_TANF
&& fcode1
== BUILT_IN_SINF
)
11194 || (fcode0
== BUILT_IN_TANL
&& fcode1
== BUILT_IN_SINL
)))
11196 tree arg00
= CALL_EXPR_ARG (arg0
, 0);
11197 tree arg01
= CALL_EXPR_ARG (arg1
, 0);
11199 if (! HONOR_NANS (TYPE_MODE (TREE_TYPE (arg00
)))
11200 && ! HONOR_INFINITIES (TYPE_MODE (TREE_TYPE (arg00
)))
11201 && operand_equal_p (arg00
, arg01
, 0))
11203 tree cosfn
= mathfn_built_in (type
, BUILT_IN_COS
);
11205 if (cosfn
!= NULL_TREE
)
11207 tree tmp
= build_call_expr (cosfn
, 1, arg00
);
11208 return fold_build2 (RDIV_EXPR
, type
,
11209 build_real (type
, dconst1
),
11215 /* Optimize pow(x,c)/x as pow(x,c-1). */
11216 if (fcode0
== BUILT_IN_POW
11217 || fcode0
== BUILT_IN_POWF
11218 || fcode0
== BUILT_IN_POWL
)
11220 tree arg00
= CALL_EXPR_ARG (arg0
, 0);
11221 tree arg01
= CALL_EXPR_ARG (arg0
, 1);
11222 if (TREE_CODE (arg01
) == REAL_CST
11223 && !TREE_OVERFLOW (arg01
)
11224 && operand_equal_p (arg1
, arg00
, 0))
11226 tree powfn
= TREE_OPERAND (CALL_EXPR_FN (arg0
), 0);
11230 c
= TREE_REAL_CST (arg01
);
11231 real_arithmetic (&c
, MINUS_EXPR
, &c
, &dconst1
);
11232 arg
= build_real (type
, c
);
11233 return build_call_expr (powfn
, 2, arg1
, arg
);
11237 /* Optimize a/root(b/c) into a*root(c/b). */
11238 if (BUILTIN_ROOT_P (fcode1
))
11240 tree rootarg
= CALL_EXPR_ARG (arg1
, 0);
11242 if (TREE_CODE (rootarg
) == RDIV_EXPR
)
11244 tree rootfn
= TREE_OPERAND (CALL_EXPR_FN (arg1
), 0);
11245 tree b
= TREE_OPERAND (rootarg
, 0);
11246 tree c
= TREE_OPERAND (rootarg
, 1);
11248 tree tmp
= fold_build2 (RDIV_EXPR
, type
, c
, b
);
11250 tmp
= build_call_expr (rootfn
, 1, tmp
);
11251 return fold_build2 (MULT_EXPR
, type
, arg0
, tmp
);
11255 /* Optimize x/expN(y) into x*expN(-y). */
11256 if (BUILTIN_EXPONENT_P (fcode1
))
11258 tree expfn
= TREE_OPERAND (CALL_EXPR_FN (arg1
), 0);
11259 tree arg
= negate_expr (CALL_EXPR_ARG (arg1
, 0));
11260 arg1
= build_call_expr (expfn
, 1, fold_convert (type
, arg
));
11261 return fold_build2 (MULT_EXPR
, type
, arg0
, arg1
);
11264 /* Optimize x/pow(y,z) into x*pow(y,-z). */
11265 if (fcode1
== BUILT_IN_POW
11266 || fcode1
== BUILT_IN_POWF
11267 || fcode1
== BUILT_IN_POWL
)
11269 tree powfn
= TREE_OPERAND (CALL_EXPR_FN (arg1
), 0);
11270 tree arg10
= CALL_EXPR_ARG (arg1
, 0);
11271 tree arg11
= CALL_EXPR_ARG (arg1
, 1);
11272 tree neg11
= fold_convert (type
, negate_expr (arg11
));
11273 arg1
= build_call_expr (powfn
, 2, arg10
, neg11
);
11274 return fold_build2 (MULT_EXPR
, type
, arg0
, arg1
);
11279 case TRUNC_DIV_EXPR
:
11280 case FLOOR_DIV_EXPR
:
11281 /* Simplify A / (B << N) where A and B are positive and B is
11282 a power of 2, to A >> (N + log2(B)). */
11283 strict_overflow_p
= false;
11284 if (TREE_CODE (arg1
) == LSHIFT_EXPR
11285 && (TYPE_UNSIGNED (type
)
11286 || tree_expr_nonnegative_warnv_p (arg0
, &strict_overflow_p
)))
11288 tree sval
= TREE_OPERAND (arg1
, 0);
11289 if (integer_pow2p (sval
) && tree_int_cst_sgn (sval
) > 0)
11291 tree sh_cnt
= TREE_OPERAND (arg1
, 1);
11292 unsigned long pow2
= exact_log2 (TREE_INT_CST_LOW (sval
));
11294 if (strict_overflow_p
)
11295 fold_overflow_warning (("assuming signed overflow does not "
11296 "occur when simplifying A / (B << N)"),
11297 WARN_STRICT_OVERFLOW_MISC
);
11299 sh_cnt
= fold_build2 (PLUS_EXPR
, TREE_TYPE (sh_cnt
),
11300 sh_cnt
, build_int_cst (NULL_TREE
, pow2
));
11301 return fold_build2 (RSHIFT_EXPR
, type
,
11302 fold_convert (type
, arg0
), sh_cnt
);
11307 case ROUND_DIV_EXPR
:
11308 case CEIL_DIV_EXPR
:
11309 case EXACT_DIV_EXPR
:
11310 if (integer_onep (arg1
))
11311 return non_lvalue (fold_convert (type
, arg0
));
11312 if (integer_zerop (arg1
))
11314 /* X / -1 is -X. */
11315 if (!TYPE_UNSIGNED (type
)
11316 && TREE_CODE (arg1
) == INTEGER_CST
11317 && TREE_INT_CST_LOW (arg1
) == (unsigned HOST_WIDE_INT
) -1
11318 && TREE_INT_CST_HIGH (arg1
) == -1)
11319 return fold_convert (type
, negate_expr (arg0
));
11321 /* Convert -A / -B to A / B when the type is signed and overflow is
11323 if ((!INTEGRAL_TYPE_P (type
) || TYPE_OVERFLOW_UNDEFINED (type
))
11324 && TREE_CODE (arg0
) == NEGATE_EXPR
11325 && negate_expr_p (arg1
))
11327 if (INTEGRAL_TYPE_P (type
))
11328 fold_overflow_warning (("assuming signed overflow does not occur "
11329 "when distributing negation across "
11331 WARN_STRICT_OVERFLOW_MISC
);
11332 return fold_build2 (code
, type
,
11333 fold_convert (type
, TREE_OPERAND (arg0
, 0)),
11334 negate_expr (arg1
));
11336 if ((!INTEGRAL_TYPE_P (type
) || TYPE_OVERFLOW_UNDEFINED (type
))
11337 && TREE_CODE (arg1
) == NEGATE_EXPR
11338 && negate_expr_p (arg0
))
11340 if (INTEGRAL_TYPE_P (type
))
11341 fold_overflow_warning (("assuming signed overflow does not occur "
11342 "when distributing negation across "
11344 WARN_STRICT_OVERFLOW_MISC
);
11345 return fold_build2 (code
, type
, negate_expr (arg0
),
11346 TREE_OPERAND (arg1
, 0));
11349 /* If arg0 is a multiple of arg1, then rewrite to the fastest div
11350 operation, EXACT_DIV_EXPR.
11352 Note that only CEIL_DIV_EXPR and FLOOR_DIV_EXPR are rewritten now.
11353 At one time others generated faster code, it's not clear if they do
11354 after the last round to changes to the DIV code in expmed.c. */
11355 if ((code
== CEIL_DIV_EXPR
|| code
== FLOOR_DIV_EXPR
)
11356 && multiple_of_p (type
, arg0
, arg1
))
11357 return fold_build2 (EXACT_DIV_EXPR
, type
, arg0
, arg1
);
11359 strict_overflow_p
= false;
11360 if (TREE_CODE (arg1
) == INTEGER_CST
11361 && 0 != (tem
= extract_muldiv (op0
, arg1
, code
, NULL_TREE
,
11362 &strict_overflow_p
)))
11364 if (strict_overflow_p
)
11365 fold_overflow_warning (("assuming signed overflow does not occur "
11366 "when simplifying division"),
11367 WARN_STRICT_OVERFLOW_MISC
);
11368 return fold_convert (type
, tem
);
11373 case CEIL_MOD_EXPR
:
11374 case FLOOR_MOD_EXPR
:
11375 case ROUND_MOD_EXPR
:
11376 case TRUNC_MOD_EXPR
:
11377 /* X % 1 is always zero, but be sure to preserve any side
11379 if (integer_onep (arg1
))
11380 return omit_one_operand (type
, integer_zero_node
, arg0
);
11382 /* X % 0, return X % 0 unchanged so that we can get the
11383 proper warnings and errors. */
11384 if (integer_zerop (arg1
))
11387 /* 0 % X is always zero, but be sure to preserve any side
11388 effects in X. Place this after checking for X == 0. */
11389 if (integer_zerop (arg0
))
11390 return omit_one_operand (type
, integer_zero_node
, arg1
);
11392 /* X % -1 is zero. */
11393 if (!TYPE_UNSIGNED (type
)
11394 && TREE_CODE (arg1
) == INTEGER_CST
11395 && TREE_INT_CST_LOW (arg1
) == (unsigned HOST_WIDE_INT
) -1
11396 && TREE_INT_CST_HIGH (arg1
) == -1)
11397 return omit_one_operand (type
, integer_zero_node
, arg0
);
11399 /* Optimize TRUNC_MOD_EXPR by a power of two into a BIT_AND_EXPR,
11400 i.e. "X % C" into "X & (C - 1)", if X and C are positive. */
11401 strict_overflow_p
= false;
11402 if ((code
== TRUNC_MOD_EXPR
|| code
== FLOOR_MOD_EXPR
)
11403 && (TYPE_UNSIGNED (type
)
11404 || tree_expr_nonnegative_warnv_p (arg0
, &strict_overflow_p
)))
11407 /* Also optimize A % (C << N) where C is a power of 2,
11408 to A & ((C << N) - 1). */
11409 if (TREE_CODE (arg1
) == LSHIFT_EXPR
)
11410 c
= TREE_OPERAND (arg1
, 0);
11412 if (integer_pow2p (c
) && tree_int_cst_sgn (c
) > 0)
11414 tree mask
= fold_build2 (MINUS_EXPR
, TREE_TYPE (arg1
), arg1
,
11415 build_int_cst (TREE_TYPE (arg1
), 1));
11416 if (strict_overflow_p
)
11417 fold_overflow_warning (("assuming signed overflow does not "
11418 "occur when simplifying "
11419 "X % (power of two)"),
11420 WARN_STRICT_OVERFLOW_MISC
);
11421 return fold_build2 (BIT_AND_EXPR
, type
,
11422 fold_convert (type
, arg0
),
11423 fold_convert (type
, mask
));
11427 /* X % -C is the same as X % C. */
11428 if (code
== TRUNC_MOD_EXPR
11429 && !TYPE_UNSIGNED (type
)
11430 && TREE_CODE (arg1
) == INTEGER_CST
11431 && !TREE_OVERFLOW (arg1
)
11432 && TREE_INT_CST_HIGH (arg1
) < 0
11433 && !TYPE_OVERFLOW_TRAPS (type
)
11434 /* Avoid this transformation if C is INT_MIN, i.e. C == -C. */
11435 && !sign_bit_p (arg1
, arg1
))
11436 return fold_build2 (code
, type
, fold_convert (type
, arg0
),
11437 fold_convert (type
, negate_expr (arg1
)));
11439 /* X % -Y is the same as X % Y. */
11440 if (code
== TRUNC_MOD_EXPR
11441 && !TYPE_UNSIGNED (type
)
11442 && TREE_CODE (arg1
) == NEGATE_EXPR
11443 && !TYPE_OVERFLOW_TRAPS (type
))
11444 return fold_build2 (code
, type
, fold_convert (type
, arg0
),
11445 fold_convert (type
, TREE_OPERAND (arg1
, 0)));
11447 if (TREE_CODE (arg1
) == INTEGER_CST
11448 && 0 != (tem
= extract_muldiv (op0
, arg1
, code
, NULL_TREE
,
11449 &strict_overflow_p
)))
11451 if (strict_overflow_p
)
11452 fold_overflow_warning (("assuming signed overflow does not occur "
11453 "when simplifying modulos"),
11454 WARN_STRICT_OVERFLOW_MISC
);
11455 return fold_convert (type
, tem
);
11462 if (integer_all_onesp (arg0
))
11463 return omit_one_operand (type
, arg0
, arg1
);
11467 /* Optimize -1 >> x for arithmetic right shifts. */
11468 if (integer_all_onesp (arg0
) && !TYPE_UNSIGNED (type
))
11469 return omit_one_operand (type
, arg0
, arg1
);
11470 /* ... fall through ... */
11474 if (integer_zerop (arg1
))
11475 return non_lvalue (fold_convert (type
, arg0
));
11476 if (integer_zerop (arg0
))
11477 return omit_one_operand (type
, arg0
, arg1
);
11479 /* Since negative shift count is not well-defined,
11480 don't try to compute it in the compiler. */
11481 if (TREE_CODE (arg1
) == INTEGER_CST
&& tree_int_cst_sgn (arg1
) < 0)
11484 /* Turn (a OP c1) OP c2 into a OP (c1+c2). */
11485 if (TREE_CODE (op0
) == code
&& host_integerp (arg1
, false)
11486 && TREE_INT_CST_LOW (arg1
) < TYPE_PRECISION (type
)
11487 && host_integerp (TREE_OPERAND (arg0
, 1), false)
11488 && TREE_INT_CST_LOW (TREE_OPERAND (arg0
, 1)) < TYPE_PRECISION (type
))
11490 HOST_WIDE_INT low
= (TREE_INT_CST_LOW (TREE_OPERAND (arg0
, 1))
11491 + TREE_INT_CST_LOW (arg1
));
11493 /* Deal with a OP (c1 + c2) being undefined but (a OP c1) OP c2
11494 being well defined. */
11495 if (low
>= TYPE_PRECISION (type
))
11497 if (code
== LROTATE_EXPR
|| code
== RROTATE_EXPR
)
11498 low
= low
% TYPE_PRECISION (type
);
11499 else if (TYPE_UNSIGNED (type
) || code
== LSHIFT_EXPR
)
11500 return build_int_cst (type
, 0);
11502 low
= TYPE_PRECISION (type
) - 1;
11505 return fold_build2 (code
, type
, TREE_OPERAND (arg0
, 0),
11506 build_int_cst (type
, low
));
11509 /* Transform (x >> c) << c into x & (-1<<c), or transform (x << c) >> c
11510 into x & ((unsigned)-1 >> c) for unsigned types. */
11511 if (((code
== LSHIFT_EXPR
&& TREE_CODE (arg0
) == RSHIFT_EXPR
)
11512 || (TYPE_UNSIGNED (type
)
11513 && code
== RSHIFT_EXPR
&& TREE_CODE (arg0
) == LSHIFT_EXPR
))
11514 && host_integerp (arg1
, false)
11515 && TREE_INT_CST_LOW (arg1
) < TYPE_PRECISION (type
)
11516 && host_integerp (TREE_OPERAND (arg0
, 1), false)
11517 && TREE_INT_CST_LOW (TREE_OPERAND (arg0
, 1)) < TYPE_PRECISION (type
))
11519 HOST_WIDE_INT low0
= TREE_INT_CST_LOW (TREE_OPERAND (arg0
, 1));
11520 HOST_WIDE_INT low1
= TREE_INT_CST_LOW (arg1
);
11526 arg00
= fold_convert (type
, TREE_OPERAND (arg0
, 0));
11528 lshift
= build_int_cst (type
, -1);
11529 lshift
= int_const_binop (code
, lshift
, arg1
, 0);
11531 return fold_build2 (BIT_AND_EXPR
, type
, arg00
, lshift
);
11535 /* Rewrite an LROTATE_EXPR by a constant into an
11536 RROTATE_EXPR by a new constant. */
11537 if (code
== LROTATE_EXPR
&& TREE_CODE (arg1
) == INTEGER_CST
)
11539 tree tem
= build_int_cst (TREE_TYPE (arg1
),
11540 GET_MODE_BITSIZE (TYPE_MODE (type
)));
11541 tem
= const_binop (MINUS_EXPR
, tem
, arg1
, 0);
11542 return fold_build2 (RROTATE_EXPR
, type
, arg0
, tem
);
11545 /* If we have a rotate of a bit operation with the rotate count and
11546 the second operand of the bit operation both constant,
11547 permute the two operations. */
11548 if (code
== RROTATE_EXPR
&& TREE_CODE (arg1
) == INTEGER_CST
11549 && (TREE_CODE (arg0
) == BIT_AND_EXPR
11550 || TREE_CODE (arg0
) == BIT_IOR_EXPR
11551 || TREE_CODE (arg0
) == BIT_XOR_EXPR
)
11552 && TREE_CODE (TREE_OPERAND (arg0
, 1)) == INTEGER_CST
)
11553 return fold_build2 (TREE_CODE (arg0
), type
,
11554 fold_build2 (code
, type
,
11555 TREE_OPERAND (arg0
, 0), arg1
),
11556 fold_build2 (code
, type
,
11557 TREE_OPERAND (arg0
, 1), arg1
));
11559 /* Two consecutive rotates adding up to the width of the mode can
11561 if (code
== RROTATE_EXPR
&& TREE_CODE (arg1
) == INTEGER_CST
11562 && TREE_CODE (arg0
) == RROTATE_EXPR
11563 && TREE_CODE (TREE_OPERAND (arg0
, 1)) == INTEGER_CST
11564 && TREE_INT_CST_HIGH (arg1
) == 0
11565 && TREE_INT_CST_HIGH (TREE_OPERAND (arg0
, 1)) == 0
11566 && ((TREE_INT_CST_LOW (arg1
)
11567 + TREE_INT_CST_LOW (TREE_OPERAND (arg0
, 1)))
11568 == (unsigned int) GET_MODE_BITSIZE (TYPE_MODE (type
))))
11569 return TREE_OPERAND (arg0
, 0);
11574 if (operand_equal_p (arg0
, arg1
, 0))
11575 return omit_one_operand (type
, arg0
, arg1
);
11576 if (INTEGRAL_TYPE_P (type
)
11577 && operand_equal_p (arg1
, TYPE_MIN_VALUE (type
), OEP_ONLY_CONST
))
11578 return omit_one_operand (type
, arg1
, arg0
);
11579 tem
= fold_minmax (MIN_EXPR
, type
, arg0
, arg1
);
11585 if (operand_equal_p (arg0
, arg1
, 0))
11586 return omit_one_operand (type
, arg0
, arg1
);
11587 if (INTEGRAL_TYPE_P (type
)
11588 && TYPE_MAX_VALUE (type
)
11589 && operand_equal_p (arg1
, TYPE_MAX_VALUE (type
), OEP_ONLY_CONST
))
11590 return omit_one_operand (type
, arg1
, arg0
);
11591 tem
= fold_minmax (MAX_EXPR
, type
, arg0
, arg1
);
11596 case TRUTH_ANDIF_EXPR
:
11597 /* Note that the operands of this must be ints
11598 and their values must be 0 or 1.
11599 ("true" is a fixed value perhaps depending on the language.) */
11600 /* If first arg is constant zero, return it. */
11601 if (integer_zerop (arg0
))
11602 return fold_convert (type
, arg0
);
11603 case TRUTH_AND_EXPR
:
11604 /* If either arg is constant true, drop it. */
11605 if (TREE_CODE (arg0
) == INTEGER_CST
&& ! integer_zerop (arg0
))
11606 return non_lvalue (fold_convert (type
, arg1
));
11607 if (TREE_CODE (arg1
) == INTEGER_CST
&& ! integer_zerop (arg1
)
11608 /* Preserve sequence points. */
11609 && (code
!= TRUTH_ANDIF_EXPR
|| ! TREE_SIDE_EFFECTS (arg0
)))
11610 return non_lvalue (fold_convert (type
, arg0
));
11611 /* If second arg is constant zero, result is zero, but first arg
11612 must be evaluated. */
11613 if (integer_zerop (arg1
))
11614 return omit_one_operand (type
, arg1
, arg0
);
11615 /* Likewise for first arg, but note that only the TRUTH_AND_EXPR
11616 case will be handled here. */
11617 if (integer_zerop (arg0
))
11618 return omit_one_operand (type
, arg0
, arg1
);
11620 /* !X && X is always false. */
11621 if (TREE_CODE (arg0
) == TRUTH_NOT_EXPR
11622 && operand_equal_p (TREE_OPERAND (arg0
, 0), arg1
, 0))
11623 return omit_one_operand (type
, integer_zero_node
, arg1
);
11624 /* X && !X is always false. */
11625 if (TREE_CODE (arg1
) == TRUTH_NOT_EXPR
11626 && operand_equal_p (arg0
, TREE_OPERAND (arg1
, 0), 0))
11627 return omit_one_operand (type
, integer_zero_node
, arg0
);
11629 /* A < X && A + 1 > Y ==> A < X && A >= Y. Normally A + 1 > Y
11630 means A >= Y && A != MAX, but in this case we know that
11633 if (!TREE_SIDE_EFFECTS (arg0
)
11634 && !TREE_SIDE_EFFECTS (arg1
))
11636 tem
= fold_to_nonsharp_ineq_using_bound (arg0
, arg1
);
11637 if (tem
&& !operand_equal_p (tem
, arg0
, 0))
11638 return fold_build2 (code
, type
, tem
, arg1
);
11640 tem
= fold_to_nonsharp_ineq_using_bound (arg1
, arg0
);
11641 if (tem
&& !operand_equal_p (tem
, arg1
, 0))
11642 return fold_build2 (code
, type
, arg0
, tem
);
11646 /* We only do these simplifications if we are optimizing. */
11650 /* Check for things like (A || B) && (A || C). We can convert this
11651 to A || (B && C). Note that either operator can be any of the four
11652 truth and/or operations and the transformation will still be
11653 valid. Also note that we only care about order for the
11654 ANDIF and ORIF operators. If B contains side effects, this
11655 might change the truth-value of A. */
11656 if (TREE_CODE (arg0
) == TREE_CODE (arg1
)
11657 && (TREE_CODE (arg0
) == TRUTH_ANDIF_EXPR
11658 || TREE_CODE (arg0
) == TRUTH_ORIF_EXPR
11659 || TREE_CODE (arg0
) == TRUTH_AND_EXPR
11660 || TREE_CODE (arg0
) == TRUTH_OR_EXPR
)
11661 && ! TREE_SIDE_EFFECTS (TREE_OPERAND (arg0
, 1)))
11663 tree a00
= TREE_OPERAND (arg0
, 0);
11664 tree a01
= TREE_OPERAND (arg0
, 1);
11665 tree a10
= TREE_OPERAND (arg1
, 0);
11666 tree a11
= TREE_OPERAND (arg1
, 1);
11667 int commutative
= ((TREE_CODE (arg0
) == TRUTH_OR_EXPR
11668 || TREE_CODE (arg0
) == TRUTH_AND_EXPR
)
11669 && (code
== TRUTH_AND_EXPR
11670 || code
== TRUTH_OR_EXPR
));
11672 if (operand_equal_p (a00
, a10
, 0))
11673 return fold_build2 (TREE_CODE (arg0
), type
, a00
,
11674 fold_build2 (code
, type
, a01
, a11
));
11675 else if (commutative
&& operand_equal_p (a00
, a11
, 0))
11676 return fold_build2 (TREE_CODE (arg0
), type
, a00
,
11677 fold_build2 (code
, type
, a01
, a10
));
11678 else if (commutative
&& operand_equal_p (a01
, a10
, 0))
11679 return fold_build2 (TREE_CODE (arg0
), type
, a01
,
11680 fold_build2 (code
, type
, a00
, a11
));
11682 /* This case if tricky because we must either have commutative
11683 operators or else A10 must not have side-effects. */
11685 else if ((commutative
|| ! TREE_SIDE_EFFECTS (a10
))
11686 && operand_equal_p (a01
, a11
, 0))
11687 return fold_build2 (TREE_CODE (arg0
), type
,
11688 fold_build2 (code
, type
, a00
, a10
),
11692 /* See if we can build a range comparison. */
11693 if (0 != (tem
= fold_range_test (code
, type
, op0
, op1
)))
11696 /* Check for the possibility of merging component references. If our
11697 lhs is another similar operation, try to merge its rhs with our
11698 rhs. Then try to merge our lhs and rhs. */
11699 if (TREE_CODE (arg0
) == code
11700 && 0 != (tem
= fold_truthop (code
, type
,
11701 TREE_OPERAND (arg0
, 1), arg1
)))
11702 return fold_build2 (code
, type
, TREE_OPERAND (arg0
, 0), tem
);
11704 if ((tem
= fold_truthop (code
, type
, arg0
, arg1
)) != 0)
11709 case TRUTH_ORIF_EXPR
:
11710 /* Note that the operands of this must be ints
11711 and their values must be 0 or true.
11712 ("true" is a fixed value perhaps depending on the language.) */
11713 /* If first arg is constant true, return it. */
11714 if (TREE_CODE (arg0
) == INTEGER_CST
&& ! integer_zerop (arg0
))
11715 return fold_convert (type
, arg0
);
11716 case TRUTH_OR_EXPR
:
11717 /* If either arg is constant zero, drop it. */
11718 if (TREE_CODE (arg0
) == INTEGER_CST
&& integer_zerop (arg0
))
11719 return non_lvalue (fold_convert (type
, arg1
));
11720 if (TREE_CODE (arg1
) == INTEGER_CST
&& integer_zerop (arg1
)
11721 /* Preserve sequence points. */
11722 && (code
!= TRUTH_ORIF_EXPR
|| ! TREE_SIDE_EFFECTS (arg0
)))
11723 return non_lvalue (fold_convert (type
, arg0
));
11724 /* If second arg is constant true, result is true, but we must
11725 evaluate first arg. */
11726 if (TREE_CODE (arg1
) == INTEGER_CST
&& ! integer_zerop (arg1
))
11727 return omit_one_operand (type
, arg1
, arg0
);
11728 /* Likewise for first arg, but note this only occurs here for
11730 if (TREE_CODE (arg0
) == INTEGER_CST
&& ! integer_zerop (arg0
))
11731 return omit_one_operand (type
, arg0
, arg1
);
11733 /* !X || X is always true. */
11734 if (TREE_CODE (arg0
) == TRUTH_NOT_EXPR
11735 && operand_equal_p (TREE_OPERAND (arg0
, 0), arg1
, 0))
11736 return omit_one_operand (type
, integer_one_node
, arg1
);
11737 /* X || !X is always true. */
11738 if (TREE_CODE (arg1
) == TRUTH_NOT_EXPR
11739 && operand_equal_p (arg0
, TREE_OPERAND (arg1
, 0), 0))
11740 return omit_one_operand (type
, integer_one_node
, arg0
);
11744 case TRUTH_XOR_EXPR
:
11745 /* If the second arg is constant zero, drop it. */
11746 if (integer_zerop (arg1
))
11747 return non_lvalue (fold_convert (type
, arg0
));
11748 /* If the second arg is constant true, this is a logical inversion. */
11749 if (integer_onep (arg1
))
11751 /* Only call invert_truthvalue if operand is a truth value. */
11752 if (TREE_CODE (TREE_TYPE (arg0
)) != BOOLEAN_TYPE
)
11753 tem
= fold_build1 (TRUTH_NOT_EXPR
, TREE_TYPE (arg0
), arg0
);
11755 tem
= invert_truthvalue (arg0
);
11756 return non_lvalue (fold_convert (type
, tem
));
11758 /* Identical arguments cancel to zero. */
11759 if (operand_equal_p (arg0
, arg1
, 0))
11760 return omit_one_operand (type
, integer_zero_node
, arg0
);
11762 /* !X ^ X is always true. */
11763 if (TREE_CODE (arg0
) == TRUTH_NOT_EXPR
11764 && operand_equal_p (TREE_OPERAND (arg0
, 0), arg1
, 0))
11765 return omit_one_operand (type
, integer_one_node
, arg1
);
11767 /* X ^ !X is always true. */
11768 if (TREE_CODE (arg1
) == TRUTH_NOT_EXPR
11769 && operand_equal_p (arg0
, TREE_OPERAND (arg1
, 0), 0))
11770 return omit_one_operand (type
, integer_one_node
, arg0
);
11776 tem
= fold_comparison (code
, type
, op0
, op1
);
11777 if (tem
!= NULL_TREE
)
11780 /* bool_var != 0 becomes bool_var. */
11781 if (TREE_CODE (TREE_TYPE (arg0
)) == BOOLEAN_TYPE
&& integer_zerop (arg1
)
11782 && code
== NE_EXPR
)
11783 return non_lvalue (fold_convert (type
, arg0
));
11785 /* bool_var == 1 becomes bool_var. */
11786 if (TREE_CODE (TREE_TYPE (arg0
)) == BOOLEAN_TYPE
&& integer_onep (arg1
)
11787 && code
== EQ_EXPR
)
11788 return non_lvalue (fold_convert (type
, arg0
));
11790 /* bool_var != 1 becomes !bool_var. */
11791 if (TREE_CODE (TREE_TYPE (arg0
)) == BOOLEAN_TYPE
&& integer_onep (arg1
)
11792 && code
== NE_EXPR
)
11793 return fold_build1 (TRUTH_NOT_EXPR
, type
, arg0
);
11795 /* bool_var == 0 becomes !bool_var. */
11796 if (TREE_CODE (TREE_TYPE (arg0
)) == BOOLEAN_TYPE
&& integer_zerop (arg1
)
11797 && code
== EQ_EXPR
)
11798 return fold_build1 (TRUTH_NOT_EXPR
, type
, arg0
);
11800 /* If this is an equality comparison of the address of two non-weak,
11801 unaliased symbols neither of which are extern (since we do not
11802 have access to attributes for externs), then we know the result. */
11803 if (TREE_CODE (arg0
) == ADDR_EXPR
11804 && VAR_OR_FUNCTION_DECL_P (TREE_OPERAND (arg0
, 0))
11805 && ! DECL_WEAK (TREE_OPERAND (arg0
, 0))
11806 && ! lookup_attribute ("alias",
11807 DECL_ATTRIBUTES (TREE_OPERAND (arg0
, 0)))
11808 && ! DECL_EXTERNAL (TREE_OPERAND (arg0
, 0))
11809 && TREE_CODE (arg1
) == ADDR_EXPR
11810 && VAR_OR_FUNCTION_DECL_P (TREE_OPERAND (arg1
, 0))
11811 && ! DECL_WEAK (TREE_OPERAND (arg1
, 0))
11812 && ! lookup_attribute ("alias",
11813 DECL_ATTRIBUTES (TREE_OPERAND (arg1
, 0)))
11814 && ! DECL_EXTERNAL (TREE_OPERAND (arg1
, 0)))
11816 /* We know that we're looking at the address of two
11817 non-weak, unaliased, static _DECL nodes.
11819 It is both wasteful and incorrect to call operand_equal_p
11820 to compare the two ADDR_EXPR nodes. It is wasteful in that
11821 all we need to do is test pointer equality for the arguments
11822 to the two ADDR_EXPR nodes. It is incorrect to use
11823 operand_equal_p as that function is NOT equivalent to a
11824 C equality test. It can in fact return false for two
11825 objects which would test as equal using the C equality
11827 bool equal
= TREE_OPERAND (arg0
, 0) == TREE_OPERAND (arg1
, 0);
11828 return constant_boolean_node (equal
11829 ? code
== EQ_EXPR
: code
!= EQ_EXPR
,
11833 /* If this is an EQ or NE comparison of a constant with a PLUS_EXPR or
11834 a MINUS_EXPR of a constant, we can convert it into a comparison with
11835 a revised constant as long as no overflow occurs. */
11836 if (TREE_CODE (arg1
) == INTEGER_CST
11837 && (TREE_CODE (arg0
) == PLUS_EXPR
11838 || TREE_CODE (arg0
) == MINUS_EXPR
)
11839 && TREE_CODE (TREE_OPERAND (arg0
, 1)) == INTEGER_CST
11840 && 0 != (tem
= const_binop (TREE_CODE (arg0
) == PLUS_EXPR
11841 ? MINUS_EXPR
: PLUS_EXPR
,
11842 fold_convert (TREE_TYPE (arg0
), arg1
),
11843 TREE_OPERAND (arg0
, 1), 0))
11844 && !TREE_OVERFLOW (tem
))
11845 return fold_build2 (code
, type
, TREE_OPERAND (arg0
, 0), tem
);
11847 /* Similarly for a NEGATE_EXPR. */
11848 if (TREE_CODE (arg0
) == NEGATE_EXPR
11849 && TREE_CODE (arg1
) == INTEGER_CST
11850 && 0 != (tem
= negate_expr (arg1
))
11851 && TREE_CODE (tem
) == INTEGER_CST
11852 && !TREE_OVERFLOW (tem
))
11853 return fold_build2 (code
, type
, TREE_OPERAND (arg0
, 0), tem
);
11855 /* Similarly for a BIT_XOR_EXPR; X ^ C1 == C2 is X == (C1 ^ C2). */
11856 if (TREE_CODE (arg0
) == BIT_XOR_EXPR
11857 && TREE_CODE (arg1
) == INTEGER_CST
11858 && TREE_CODE (TREE_OPERAND (arg0
, 1)) == INTEGER_CST
)
11859 return fold_build2 (code
, type
, TREE_OPERAND (arg0
, 0),
11860 fold_build2 (BIT_XOR_EXPR
, TREE_TYPE (arg0
),
11861 fold_convert (TREE_TYPE (arg0
), arg1
),
11862 TREE_OPERAND (arg0
, 1)));
11864 /* Transform comparisons of the form X +- C CMP X. */
11865 if ((TREE_CODE (arg0
) == PLUS_EXPR
|| TREE_CODE (arg0
) == MINUS_EXPR
)
11866 && operand_equal_p (TREE_OPERAND (arg0
, 0), arg1
, 0)
11867 && TREE_CODE (TREE_OPERAND (arg0
, 1)) == INTEGER_CST
11868 && (INTEGRAL_TYPE_P (TREE_TYPE (arg0
))
11869 || POINTER_TYPE_P (TREE_TYPE (arg0
))))
11871 tree cst
= TREE_OPERAND (arg0
, 1);
11873 if (code
== EQ_EXPR
11874 && !integer_zerop (cst
))
11875 return omit_two_operands (type
, boolean_false_node
,
11876 TREE_OPERAND (arg0
, 0), arg1
);
11878 return omit_two_operands (type
, boolean_true_node
,
11879 TREE_OPERAND (arg0
, 0), arg1
);
11882 /* If we have X - Y == 0, we can convert that to X == Y and similarly
11883 for !=. Don't do this for ordered comparisons due to overflow. */
11884 if (TREE_CODE (arg0
) == MINUS_EXPR
11885 && integer_zerop (arg1
))
11886 return fold_build2 (code
, type
,
11887 TREE_OPERAND (arg0
, 0), TREE_OPERAND (arg0
, 1));
11889 /* Convert ABS_EXPR<x> == 0 or ABS_EXPR<x> != 0 to x == 0 or x != 0. */
11890 if (TREE_CODE (arg0
) == ABS_EXPR
11891 && (integer_zerop (arg1
) || real_zerop (arg1
)))
11892 return fold_build2 (code
, type
, TREE_OPERAND (arg0
, 0), arg1
);
11894 /* If this is an EQ or NE comparison with zero and ARG0 is
11895 (1 << foo) & bar, convert it to (bar >> foo) & 1. Both require
11896 two operations, but the latter can be done in one less insn
11897 on machines that have only two-operand insns or on which a
11898 constant cannot be the first operand. */
11899 if (TREE_CODE (arg0
) == BIT_AND_EXPR
11900 && integer_zerop (arg1
))
11902 tree arg00
= TREE_OPERAND (arg0
, 0);
11903 tree arg01
= TREE_OPERAND (arg0
, 1);
11904 if (TREE_CODE (arg00
) == LSHIFT_EXPR
11905 && integer_onep (TREE_OPERAND (arg00
, 0)))
11907 fold_build2 (code
, type
,
11908 build2 (BIT_AND_EXPR
, TREE_TYPE (arg0
),
11909 build2 (RSHIFT_EXPR
, TREE_TYPE (arg00
),
11910 arg01
, TREE_OPERAND (arg00
, 1)),
11911 fold_convert (TREE_TYPE (arg0
),
11912 integer_one_node
)),
11914 else if (TREE_CODE (TREE_OPERAND (arg0
, 1)) == LSHIFT_EXPR
11915 && integer_onep (TREE_OPERAND (TREE_OPERAND (arg0
, 1), 0)))
11917 fold_build2 (code
, type
,
11918 build2 (BIT_AND_EXPR
, TREE_TYPE (arg0
),
11919 build2 (RSHIFT_EXPR
, TREE_TYPE (arg01
),
11920 arg00
, TREE_OPERAND (arg01
, 1)),
11921 fold_convert (TREE_TYPE (arg0
),
11922 integer_one_node
)),
11926 /* If this is an NE or EQ comparison of zero against the result of a
11927 signed MOD operation whose second operand is a power of 2, make
11928 the MOD operation unsigned since it is simpler and equivalent. */
11929 if (integer_zerop (arg1
)
11930 && !TYPE_UNSIGNED (TREE_TYPE (arg0
))
11931 && (TREE_CODE (arg0
) == TRUNC_MOD_EXPR
11932 || TREE_CODE (arg0
) == CEIL_MOD_EXPR
11933 || TREE_CODE (arg0
) == FLOOR_MOD_EXPR
11934 || TREE_CODE (arg0
) == ROUND_MOD_EXPR
)
11935 && integer_pow2p (TREE_OPERAND (arg0
, 1)))
11937 tree newtype
= unsigned_type_for (TREE_TYPE (arg0
));
11938 tree newmod
= fold_build2 (TREE_CODE (arg0
), newtype
,
11939 fold_convert (newtype
,
11940 TREE_OPERAND (arg0
, 0)),
11941 fold_convert (newtype
,
11942 TREE_OPERAND (arg0
, 1)));
11944 return fold_build2 (code
, type
, newmod
,
11945 fold_convert (newtype
, arg1
));
11948 /* Fold ((X >> C1) & C2) == 0 and ((X >> C1) & C2) != 0 where
11949 C1 is a valid shift constant, and C2 is a power of two, i.e.
11951 if (TREE_CODE (arg0
) == BIT_AND_EXPR
11952 && TREE_CODE (TREE_OPERAND (arg0
, 0)) == RSHIFT_EXPR
11953 && TREE_CODE (TREE_OPERAND (TREE_OPERAND (arg0
, 0), 1))
11955 && integer_pow2p (TREE_OPERAND (arg0
, 1))
11956 && integer_zerop (arg1
))
11958 tree itype
= TREE_TYPE (arg0
);
11959 unsigned HOST_WIDE_INT prec
= TYPE_PRECISION (itype
);
11960 tree arg001
= TREE_OPERAND (TREE_OPERAND (arg0
, 0), 1);
11962 /* Check for a valid shift count. */
11963 if (TREE_INT_CST_HIGH (arg001
) == 0
11964 && TREE_INT_CST_LOW (arg001
) < prec
)
11966 tree arg01
= TREE_OPERAND (arg0
, 1);
11967 tree arg000
= TREE_OPERAND (TREE_OPERAND (arg0
, 0), 0);
11968 unsigned HOST_WIDE_INT log2
= tree_log2 (arg01
);
11969 /* If (C2 << C1) doesn't overflow, then ((X >> C1) & C2) != 0
11970 can be rewritten as (X & (C2 << C1)) != 0. */
11971 if ((log2
+ TREE_INT_CST_LOW (arg001
)) < prec
)
11973 tem
= fold_build2 (LSHIFT_EXPR
, itype
, arg01
, arg001
);
11974 tem
= fold_build2 (BIT_AND_EXPR
, itype
, arg000
, tem
);
11975 return fold_build2 (code
, type
, tem
, arg1
);
11977 /* Otherwise, for signed (arithmetic) shifts,
11978 ((X >> C1) & C2) != 0 is rewritten as X < 0, and
11979 ((X >> C1) & C2) == 0 is rewritten as X >= 0. */
11980 else if (!TYPE_UNSIGNED (itype
))
11981 return fold_build2 (code
== EQ_EXPR
? GE_EXPR
: LT_EXPR
, type
,
11982 arg000
, build_int_cst (itype
, 0));
11983 /* Otherwise, of unsigned (logical) shifts,
11984 ((X >> C1) & C2) != 0 is rewritten as (X,false), and
11985 ((X >> C1) & C2) == 0 is rewritten as (X,true). */
11987 return omit_one_operand (type
,
11988 code
== EQ_EXPR
? integer_one_node
11989 : integer_zero_node
,
11994 /* If this is an NE comparison of zero with an AND of one, remove the
11995 comparison since the AND will give the correct value. */
11996 if (code
== NE_EXPR
11997 && integer_zerop (arg1
)
11998 && TREE_CODE (arg0
) == BIT_AND_EXPR
11999 && integer_onep (TREE_OPERAND (arg0
, 1)))
12000 return fold_convert (type
, arg0
);
12002 /* If we have (A & C) == C where C is a power of 2, convert this into
12003 (A & C) != 0. Similarly for NE_EXPR. */
12004 if (TREE_CODE (arg0
) == BIT_AND_EXPR
12005 && integer_pow2p (TREE_OPERAND (arg0
, 1))
12006 && operand_equal_p (TREE_OPERAND (arg0
, 1), arg1
, 0))
12007 return fold_build2 (code
== EQ_EXPR
? NE_EXPR
: EQ_EXPR
, type
,
12008 arg0
, fold_convert (TREE_TYPE (arg0
),
12009 integer_zero_node
));
12011 /* If we have (A & C) != 0 or (A & C) == 0 and C is the sign
12012 bit, then fold the expression into A < 0 or A >= 0. */
12013 tem
= fold_single_bit_test_into_sign_test (code
, arg0
, arg1
, type
);
12017 /* If we have (A & C) == D where D & ~C != 0, convert this into 0.
12018 Similarly for NE_EXPR. */
12019 if (TREE_CODE (arg0
) == BIT_AND_EXPR
12020 && TREE_CODE (arg1
) == INTEGER_CST
12021 && TREE_CODE (TREE_OPERAND (arg0
, 1)) == INTEGER_CST
)
12023 tree notc
= fold_build1 (BIT_NOT_EXPR
,
12024 TREE_TYPE (TREE_OPERAND (arg0
, 1)),
12025 TREE_OPERAND (arg0
, 1));
12026 tree dandnotc
= fold_build2 (BIT_AND_EXPR
, TREE_TYPE (arg0
),
12028 tree rslt
= code
== EQ_EXPR
? integer_zero_node
: integer_one_node
;
12029 if (integer_nonzerop (dandnotc
))
12030 return omit_one_operand (type
, rslt
, arg0
);
12033 /* If we have (A | C) == D where C & ~D != 0, convert this into 0.
12034 Similarly for NE_EXPR. */
12035 if (TREE_CODE (arg0
) == BIT_IOR_EXPR
12036 && TREE_CODE (arg1
) == INTEGER_CST
12037 && TREE_CODE (TREE_OPERAND (arg0
, 1)) == INTEGER_CST
)
12039 tree notd
= fold_build1 (BIT_NOT_EXPR
, TREE_TYPE (arg1
), arg1
);
12040 tree candnotd
= fold_build2 (BIT_AND_EXPR
, TREE_TYPE (arg0
),
12041 TREE_OPERAND (arg0
, 1), notd
);
12042 tree rslt
= code
== EQ_EXPR
? integer_zero_node
: integer_one_node
;
12043 if (integer_nonzerop (candnotd
))
12044 return omit_one_operand (type
, rslt
, arg0
);
12047 /* If this is a comparison of a field, we may be able to simplify it. */
12048 if ((TREE_CODE (arg0
) == COMPONENT_REF
12049 || TREE_CODE (arg0
) == BIT_FIELD_REF
)
12050 /* Handle the constant case even without -O
12051 to make sure the warnings are given. */
12052 && (optimize
|| TREE_CODE (arg1
) == INTEGER_CST
))
12054 t1
= optimize_bit_field_compare (code
, type
, arg0
, arg1
);
12059 /* Optimize comparisons of strlen vs zero to a compare of the
12060 first character of the string vs zero. To wit,
12061 strlen(ptr) == 0 => *ptr == 0
12062 strlen(ptr) != 0 => *ptr != 0
12063 Other cases should reduce to one of these two (or a constant)
12064 due to the return value of strlen being unsigned. */
12065 if (TREE_CODE (arg0
) == CALL_EXPR
12066 && integer_zerop (arg1
))
12068 tree fndecl
= get_callee_fndecl (arg0
);
12071 && DECL_BUILT_IN_CLASS (fndecl
) == BUILT_IN_NORMAL
12072 && DECL_FUNCTION_CODE (fndecl
) == BUILT_IN_STRLEN
12073 && call_expr_nargs (arg0
) == 1
12074 && TREE_CODE (TREE_TYPE (CALL_EXPR_ARG (arg0
, 0))) == POINTER_TYPE
)
12076 tree iref
= build_fold_indirect_ref (CALL_EXPR_ARG (arg0
, 0));
12077 return fold_build2 (code
, type
, iref
,
12078 build_int_cst (TREE_TYPE (iref
), 0));
12082 /* Fold (X >> C) != 0 into X < 0 if C is one less than the width
12083 of X. Similarly fold (X >> C) == 0 into X >= 0. */
12084 if (TREE_CODE (arg0
) == RSHIFT_EXPR
12085 && integer_zerop (arg1
)
12086 && TREE_CODE (TREE_OPERAND (arg0
, 1)) == INTEGER_CST
)
12088 tree arg00
= TREE_OPERAND (arg0
, 0);
12089 tree arg01
= TREE_OPERAND (arg0
, 1);
12090 tree itype
= TREE_TYPE (arg00
);
12091 if (TREE_INT_CST_HIGH (arg01
) == 0
12092 && TREE_INT_CST_LOW (arg01
)
12093 == (unsigned HOST_WIDE_INT
) (TYPE_PRECISION (itype
) - 1))
12095 if (TYPE_UNSIGNED (itype
))
12097 itype
= signed_type_for (itype
);
12098 arg00
= fold_convert (itype
, arg00
);
12100 return fold_build2 (code
== EQ_EXPR
? GE_EXPR
: LT_EXPR
,
12101 type
, arg00
, build_int_cst (itype
, 0));
12105 /* (X ^ Y) == 0 becomes X == Y, and (X ^ Y) != 0 becomes X != Y. */
12106 if (integer_zerop (arg1
)
12107 && TREE_CODE (arg0
) == BIT_XOR_EXPR
)
12108 return fold_build2 (code
, type
, TREE_OPERAND (arg0
, 0),
12109 TREE_OPERAND (arg0
, 1));
12111 /* (X ^ Y) == Y becomes X == 0. We know that Y has no side-effects. */
12112 if (TREE_CODE (arg0
) == BIT_XOR_EXPR
12113 && operand_equal_p (TREE_OPERAND (arg0
, 1), arg1
, 0))
12114 return fold_build2 (code
, type
, TREE_OPERAND (arg0
, 0),
12115 build_int_cst (TREE_TYPE (arg1
), 0));
12116 /* Likewise (X ^ Y) == X becomes Y == 0. X has no side-effects. */
12117 if (TREE_CODE (arg0
) == BIT_XOR_EXPR
12118 && operand_equal_p (TREE_OPERAND (arg0
, 0), arg1
, 0)
12119 && reorder_operands_p (TREE_OPERAND (arg0
, 1), arg1
))
12120 return fold_build2 (code
, type
, TREE_OPERAND (arg0
, 1),
12121 build_int_cst (TREE_TYPE (arg1
), 0));
12123 /* (X ^ C1) op C2 can be rewritten as X op (C1 ^ C2). */
12124 if (TREE_CODE (arg0
) == BIT_XOR_EXPR
12125 && TREE_CODE (arg1
) == INTEGER_CST
12126 && TREE_CODE (TREE_OPERAND (arg0
, 1)) == INTEGER_CST
)
12127 return fold_build2 (code
, type
, TREE_OPERAND (arg0
, 0),
12128 fold_build2 (BIT_XOR_EXPR
, TREE_TYPE (arg1
),
12129 TREE_OPERAND (arg0
, 1), arg1
));
12131 /* Fold (~X & C) == 0 into (X & C) != 0 and (~X & C) != 0 into
12132 (X & C) == 0 when C is a single bit. */
12133 if (TREE_CODE (arg0
) == BIT_AND_EXPR
12134 && TREE_CODE (TREE_OPERAND (arg0
, 0)) == BIT_NOT_EXPR
12135 && integer_zerop (arg1
)
12136 && integer_pow2p (TREE_OPERAND (arg0
, 1)))
12138 tem
= fold_build2 (BIT_AND_EXPR
, TREE_TYPE (arg0
),
12139 TREE_OPERAND (TREE_OPERAND (arg0
, 0), 0),
12140 TREE_OPERAND (arg0
, 1));
12141 return fold_build2 (code
== EQ_EXPR
? NE_EXPR
: EQ_EXPR
,
12145 /* Fold ((X & C) ^ C) eq/ne 0 into (X & C) ne/eq 0, when the
12146 constant C is a power of two, i.e. a single bit. */
12147 if (TREE_CODE (arg0
) == BIT_XOR_EXPR
12148 && TREE_CODE (TREE_OPERAND (arg0
, 0)) == BIT_AND_EXPR
12149 && integer_zerop (arg1
)
12150 && integer_pow2p (TREE_OPERAND (arg0
, 1))
12151 && operand_equal_p (TREE_OPERAND (TREE_OPERAND (arg0
, 0), 1),
12152 TREE_OPERAND (arg0
, 1), OEP_ONLY_CONST
))
12154 tree arg00
= TREE_OPERAND (arg0
, 0);
12155 return fold_build2 (code
== EQ_EXPR
? NE_EXPR
: EQ_EXPR
, type
,
12156 arg00
, build_int_cst (TREE_TYPE (arg00
), 0));
12159 /* Likewise, fold ((X ^ C) & C) eq/ne 0 into (X & C) ne/eq 0,
12160 when is C is a power of two, i.e. a single bit. */
12161 if (TREE_CODE (arg0
) == BIT_AND_EXPR
12162 && TREE_CODE (TREE_OPERAND (arg0
, 0)) == BIT_XOR_EXPR
12163 && integer_zerop (arg1
)
12164 && integer_pow2p (TREE_OPERAND (arg0
, 1))
12165 && operand_equal_p (TREE_OPERAND (TREE_OPERAND (arg0
, 0), 1),
12166 TREE_OPERAND (arg0
, 1), OEP_ONLY_CONST
))
12168 tree arg000
= TREE_OPERAND (TREE_OPERAND (arg0
, 0), 0);
12169 tem
= fold_build2 (BIT_AND_EXPR
, TREE_TYPE (arg000
),
12170 arg000
, TREE_OPERAND (arg0
, 1));
12171 return fold_build2 (code
== EQ_EXPR
? NE_EXPR
: EQ_EXPR
, type
,
12172 tem
, build_int_cst (TREE_TYPE (tem
), 0));
12175 if (integer_zerop (arg1
)
12176 && tree_expr_nonzero_p (arg0
))
12178 tree res
= constant_boolean_node (code
==NE_EXPR
, type
);
12179 return omit_one_operand (type
, res
, arg0
);
12182 /* Fold -X op -Y as X op Y, where op is eq/ne. */
12183 if (TREE_CODE (arg0
) == NEGATE_EXPR
12184 && TREE_CODE (arg1
) == NEGATE_EXPR
)
12185 return fold_build2 (code
, type
,
12186 TREE_OPERAND (arg0
, 0),
12187 TREE_OPERAND (arg1
, 0));
12189 /* Fold (X & C) op (Y & C) as (X ^ Y) & C op 0", and symmetries. */
12190 if (TREE_CODE (arg0
) == BIT_AND_EXPR
12191 && TREE_CODE (arg1
) == BIT_AND_EXPR
)
12193 tree arg00
= TREE_OPERAND (arg0
, 0);
12194 tree arg01
= TREE_OPERAND (arg0
, 1);
12195 tree arg10
= TREE_OPERAND (arg1
, 0);
12196 tree arg11
= TREE_OPERAND (arg1
, 1);
12197 tree itype
= TREE_TYPE (arg0
);
12199 if (operand_equal_p (arg01
, arg11
, 0))
12200 return fold_build2 (code
, type
,
12201 fold_build2 (BIT_AND_EXPR
, itype
,
12202 fold_build2 (BIT_XOR_EXPR
, itype
,
12205 build_int_cst (itype
, 0));
12207 if (operand_equal_p (arg01
, arg10
, 0))
12208 return fold_build2 (code
, type
,
12209 fold_build2 (BIT_AND_EXPR
, itype
,
12210 fold_build2 (BIT_XOR_EXPR
, itype
,
12213 build_int_cst (itype
, 0));
12215 if (operand_equal_p (arg00
, arg11
, 0))
12216 return fold_build2 (code
, type
,
12217 fold_build2 (BIT_AND_EXPR
, itype
,
12218 fold_build2 (BIT_XOR_EXPR
, itype
,
12221 build_int_cst (itype
, 0));
12223 if (operand_equal_p (arg00
, arg10
, 0))
12224 return fold_build2 (code
, type
,
12225 fold_build2 (BIT_AND_EXPR
, itype
,
12226 fold_build2 (BIT_XOR_EXPR
, itype
,
12229 build_int_cst (itype
, 0));
12232 if (TREE_CODE (arg0
) == BIT_XOR_EXPR
12233 && TREE_CODE (arg1
) == BIT_XOR_EXPR
)
12235 tree arg00
= TREE_OPERAND (arg0
, 0);
12236 tree arg01
= TREE_OPERAND (arg0
, 1);
12237 tree arg10
= TREE_OPERAND (arg1
, 0);
12238 tree arg11
= TREE_OPERAND (arg1
, 1);
12239 tree itype
= TREE_TYPE (arg0
);
12241 /* Optimize (X ^ Z) op (Y ^ Z) as X op Y, and symmetries.
12242 operand_equal_p guarantees no side-effects so we don't need
12243 to use omit_one_operand on Z. */
12244 if (operand_equal_p (arg01
, arg11
, 0))
12245 return fold_build2 (code
, type
, arg00
, arg10
);
12246 if (operand_equal_p (arg01
, arg10
, 0))
12247 return fold_build2 (code
, type
, arg00
, arg11
);
12248 if (operand_equal_p (arg00
, arg11
, 0))
12249 return fold_build2 (code
, type
, arg01
, arg10
);
12250 if (operand_equal_p (arg00
, arg10
, 0))
12251 return fold_build2 (code
, type
, arg01
, arg11
);
12253 /* Optimize (X ^ C1) op (Y ^ C2) as (X ^ (C1 ^ C2)) op Y. */
12254 if (TREE_CODE (arg01
) == INTEGER_CST
12255 && TREE_CODE (arg11
) == INTEGER_CST
)
12256 return fold_build2 (code
, type
,
12257 fold_build2 (BIT_XOR_EXPR
, itype
, arg00
,
12258 fold_build2 (BIT_XOR_EXPR
, itype
,
12263 /* Attempt to simplify equality/inequality comparisons of complex
12264 values. Only lower the comparison if the result is known or
12265 can be simplified to a single scalar comparison. */
12266 if ((TREE_CODE (arg0
) == COMPLEX_EXPR
12267 || TREE_CODE (arg0
) == COMPLEX_CST
)
12268 && (TREE_CODE (arg1
) == COMPLEX_EXPR
12269 || TREE_CODE (arg1
) == COMPLEX_CST
))
12271 tree real0
, imag0
, real1
, imag1
;
12274 if (TREE_CODE (arg0
) == COMPLEX_EXPR
)
12276 real0
= TREE_OPERAND (arg0
, 0);
12277 imag0
= TREE_OPERAND (arg0
, 1);
12281 real0
= TREE_REALPART (arg0
);
12282 imag0
= TREE_IMAGPART (arg0
);
12285 if (TREE_CODE (arg1
) == COMPLEX_EXPR
)
12287 real1
= TREE_OPERAND (arg1
, 0);
12288 imag1
= TREE_OPERAND (arg1
, 1);
12292 real1
= TREE_REALPART (arg1
);
12293 imag1
= TREE_IMAGPART (arg1
);
12296 rcond
= fold_binary (code
, type
, real0
, real1
);
12297 if (rcond
&& TREE_CODE (rcond
) == INTEGER_CST
)
12299 if (integer_zerop (rcond
))
12301 if (code
== EQ_EXPR
)
12302 return omit_two_operands (type
, boolean_false_node
,
12304 return fold_build2 (NE_EXPR
, type
, imag0
, imag1
);
12308 if (code
== NE_EXPR
)
12309 return omit_two_operands (type
, boolean_true_node
,
12311 return fold_build2 (EQ_EXPR
, type
, imag0
, imag1
);
12315 icond
= fold_binary (code
, type
, imag0
, imag1
);
12316 if (icond
&& TREE_CODE (icond
) == INTEGER_CST
)
12318 if (integer_zerop (icond
))
12320 if (code
== EQ_EXPR
)
12321 return omit_two_operands (type
, boolean_false_node
,
12323 return fold_build2 (NE_EXPR
, type
, real0
, real1
);
12327 if (code
== NE_EXPR
)
12328 return omit_two_operands (type
, boolean_true_node
,
12330 return fold_build2 (EQ_EXPR
, type
, real0
, real1
);
12341 tem
= fold_comparison (code
, type
, op0
, op1
);
12342 if (tem
!= NULL_TREE
)
12345 /* Transform comparisons of the form X +- C CMP X. */
12346 if ((TREE_CODE (arg0
) == PLUS_EXPR
|| TREE_CODE (arg0
) == MINUS_EXPR
)
12347 && operand_equal_p (TREE_OPERAND (arg0
, 0), arg1
, 0)
12348 && ((TREE_CODE (TREE_OPERAND (arg0
, 1)) == REAL_CST
12349 && !HONOR_SNANS (TYPE_MODE (TREE_TYPE (arg0
))))
12350 || (TREE_CODE (TREE_OPERAND (arg0
, 1)) == INTEGER_CST
12351 && TYPE_OVERFLOW_UNDEFINED (TREE_TYPE (arg1
)))))
12353 tree arg01
= TREE_OPERAND (arg0
, 1);
12354 enum tree_code code0
= TREE_CODE (arg0
);
12357 if (TREE_CODE (arg01
) == REAL_CST
)
12358 is_positive
= REAL_VALUE_NEGATIVE (TREE_REAL_CST (arg01
)) ? -1 : 1;
12360 is_positive
= tree_int_cst_sgn (arg01
);
12362 /* (X - c) > X becomes false. */
12363 if (code
== GT_EXPR
12364 && ((code0
== MINUS_EXPR
&& is_positive
>= 0)
12365 || (code0
== PLUS_EXPR
&& is_positive
<= 0)))
12367 if (TREE_CODE (arg01
) == INTEGER_CST
12368 && TYPE_OVERFLOW_UNDEFINED (TREE_TYPE (arg1
)))
12369 fold_overflow_warning (("assuming signed overflow does not "
12370 "occur when assuming that (X - c) > X "
12371 "is always false"),
12372 WARN_STRICT_OVERFLOW_ALL
);
12373 return constant_boolean_node (0, type
);
12376 /* Likewise (X + c) < X becomes false. */
12377 if (code
== LT_EXPR
12378 && ((code0
== PLUS_EXPR
&& is_positive
>= 0)
12379 || (code0
== MINUS_EXPR
&& is_positive
<= 0)))
12381 if (TREE_CODE (arg01
) == INTEGER_CST
12382 && TYPE_OVERFLOW_UNDEFINED (TREE_TYPE (arg1
)))
12383 fold_overflow_warning (("assuming signed overflow does not "
12384 "occur when assuming that "
12385 "(X + c) < X is always false"),
12386 WARN_STRICT_OVERFLOW_ALL
);
12387 return constant_boolean_node (0, type
);
12390 /* Convert (X - c) <= X to true. */
12391 if (!HONOR_NANS (TYPE_MODE (TREE_TYPE (arg1
)))
12393 && ((code0
== MINUS_EXPR
&& is_positive
>= 0)
12394 || (code0
== PLUS_EXPR
&& is_positive
<= 0)))
12396 if (TREE_CODE (arg01
) == INTEGER_CST
12397 && TYPE_OVERFLOW_UNDEFINED (TREE_TYPE (arg1
)))
12398 fold_overflow_warning (("assuming signed overflow does not "
12399 "occur when assuming that "
12400 "(X - c) <= X is always true"),
12401 WARN_STRICT_OVERFLOW_ALL
);
12402 return constant_boolean_node (1, type
);
12405 /* Convert (X + c) >= X to true. */
12406 if (!HONOR_NANS (TYPE_MODE (TREE_TYPE (arg1
)))
12408 && ((code0
== PLUS_EXPR
&& is_positive
>= 0)
12409 || (code0
== MINUS_EXPR
&& is_positive
<= 0)))
12411 if (TREE_CODE (arg01
) == INTEGER_CST
12412 && TYPE_OVERFLOW_UNDEFINED (TREE_TYPE (arg1
)))
12413 fold_overflow_warning (("assuming signed overflow does not "
12414 "occur when assuming that "
12415 "(X + c) >= X is always true"),
12416 WARN_STRICT_OVERFLOW_ALL
);
12417 return constant_boolean_node (1, type
);
12420 if (TREE_CODE (arg01
) == INTEGER_CST
)
12422 /* Convert X + c > X and X - c < X to true for integers. */
12423 if (code
== GT_EXPR
12424 && ((code0
== PLUS_EXPR
&& is_positive
> 0)
12425 || (code0
== MINUS_EXPR
&& is_positive
< 0)))
12427 if (TYPE_OVERFLOW_UNDEFINED (TREE_TYPE (arg1
)))
12428 fold_overflow_warning (("assuming signed overflow does "
12429 "not occur when assuming that "
12430 "(X + c) > X is always true"),
12431 WARN_STRICT_OVERFLOW_ALL
);
12432 return constant_boolean_node (1, type
);
12435 if (code
== LT_EXPR
12436 && ((code0
== MINUS_EXPR
&& is_positive
> 0)
12437 || (code0
== PLUS_EXPR
&& is_positive
< 0)))
12439 if (TYPE_OVERFLOW_UNDEFINED (TREE_TYPE (arg1
)))
12440 fold_overflow_warning (("assuming signed overflow does "
12441 "not occur when assuming that "
12442 "(X - c) < X is always true"),
12443 WARN_STRICT_OVERFLOW_ALL
);
12444 return constant_boolean_node (1, type
);
12447 /* Convert X + c <= X and X - c >= X to false for integers. */
12448 if (code
== LE_EXPR
12449 && ((code0
== PLUS_EXPR
&& is_positive
> 0)
12450 || (code0
== MINUS_EXPR
&& is_positive
< 0)))
12452 if (TYPE_OVERFLOW_UNDEFINED (TREE_TYPE (arg1
)))
12453 fold_overflow_warning (("assuming signed overflow does "
12454 "not occur when assuming that "
12455 "(X + c) <= X is always false"),
12456 WARN_STRICT_OVERFLOW_ALL
);
12457 return constant_boolean_node (0, type
);
12460 if (code
== GE_EXPR
12461 && ((code0
== MINUS_EXPR
&& is_positive
> 0)
12462 || (code0
== PLUS_EXPR
&& is_positive
< 0)))
12464 if (TYPE_OVERFLOW_UNDEFINED (TREE_TYPE (arg1
)))
12465 fold_overflow_warning (("assuming signed overflow does "
12466 "not occur when assuming that "
12467 "(X - c) >= X is always false"),
12468 WARN_STRICT_OVERFLOW_ALL
);
12469 return constant_boolean_node (0, type
);
12474 /* Change X >= C to X > (C - 1) and X < C to X <= (C - 1) if C > 0.
12475 This transformation affects the cases which are handled in later
12476 optimizations involving comparisons with non-negative constants. */
12477 if (TREE_CODE (arg1
) == INTEGER_CST
12478 && TREE_CODE (arg0
) != INTEGER_CST
12479 && tree_int_cst_sgn (arg1
) > 0)
12481 if (code
== GE_EXPR
)
12483 arg1
= const_binop (MINUS_EXPR
, arg1
,
12484 build_int_cst (TREE_TYPE (arg1
), 1), 0);
12485 return fold_build2 (GT_EXPR
, type
, arg0
,
12486 fold_convert (TREE_TYPE (arg0
), arg1
));
12488 if (code
== LT_EXPR
)
12490 arg1
= const_binop (MINUS_EXPR
, arg1
,
12491 build_int_cst (TREE_TYPE (arg1
), 1), 0);
12492 return fold_build2 (LE_EXPR
, type
, arg0
,
12493 fold_convert (TREE_TYPE (arg0
), arg1
));
12497 /* Comparisons with the highest or lowest possible integer of
12498 the specified precision will have known values. */
12500 tree arg1_type
= TREE_TYPE (arg1
);
12501 unsigned int width
= TYPE_PRECISION (arg1_type
);
12503 if (TREE_CODE (arg1
) == INTEGER_CST
12504 && !TREE_OVERFLOW (arg1
)
12505 && width
<= 2 * HOST_BITS_PER_WIDE_INT
12506 && (INTEGRAL_TYPE_P (arg1_type
) || POINTER_TYPE_P (arg1_type
)))
12508 HOST_WIDE_INT signed_max_hi
;
12509 unsigned HOST_WIDE_INT signed_max_lo
;
12510 unsigned HOST_WIDE_INT max_hi
, max_lo
, min_hi
, min_lo
;
12512 if (width
<= HOST_BITS_PER_WIDE_INT
)
12514 signed_max_lo
= ((unsigned HOST_WIDE_INT
) 1 << (width
- 1))
12519 if (TYPE_UNSIGNED (arg1_type
))
12521 max_lo
= ((unsigned HOST_WIDE_INT
) 2 << (width
- 1)) - 1;
12527 max_lo
= signed_max_lo
;
12528 min_lo
= ((unsigned HOST_WIDE_INT
) -1 << (width
- 1));
12534 width
-= HOST_BITS_PER_WIDE_INT
;
12535 signed_max_lo
= -1;
12536 signed_max_hi
= ((unsigned HOST_WIDE_INT
) 1 << (width
- 1))
12541 if (TYPE_UNSIGNED (arg1_type
))
12543 max_hi
= ((unsigned HOST_WIDE_INT
) 2 << (width
- 1)) - 1;
12548 max_hi
= signed_max_hi
;
12549 min_hi
= ((unsigned HOST_WIDE_INT
) -1 << (width
- 1));
12553 if ((unsigned HOST_WIDE_INT
) TREE_INT_CST_HIGH (arg1
) == max_hi
12554 && TREE_INT_CST_LOW (arg1
) == max_lo
)
12558 return omit_one_operand (type
, integer_zero_node
, arg0
);
12561 return fold_build2 (EQ_EXPR
, type
, op0
, op1
);
12564 return omit_one_operand (type
, integer_one_node
, arg0
);
12567 return fold_build2 (NE_EXPR
, type
, op0
, op1
);
12569 /* The GE_EXPR and LT_EXPR cases above are not normally
12570 reached because of previous transformations. */
12575 else if ((unsigned HOST_WIDE_INT
) TREE_INT_CST_HIGH (arg1
)
12577 && TREE_INT_CST_LOW (arg1
) == max_lo
- 1)
12581 arg1
= const_binop (PLUS_EXPR
, arg1
,
12582 build_int_cst (TREE_TYPE (arg1
), 1), 0);
12583 return fold_build2 (EQ_EXPR
, type
,
12584 fold_convert (TREE_TYPE (arg1
), arg0
),
12587 arg1
= const_binop (PLUS_EXPR
, arg1
,
12588 build_int_cst (TREE_TYPE (arg1
), 1), 0);
12589 return fold_build2 (NE_EXPR
, type
,
12590 fold_convert (TREE_TYPE (arg1
), arg0
),
12595 else if ((unsigned HOST_WIDE_INT
) TREE_INT_CST_HIGH (arg1
)
12597 && TREE_INT_CST_LOW (arg1
) == min_lo
)
12601 return omit_one_operand (type
, integer_zero_node
, arg0
);
12604 return fold_build2 (EQ_EXPR
, type
, op0
, op1
);
12607 return omit_one_operand (type
, integer_one_node
, arg0
);
12610 return fold_build2 (NE_EXPR
, type
, op0
, op1
);
12615 else if ((unsigned HOST_WIDE_INT
) TREE_INT_CST_HIGH (arg1
)
12617 && TREE_INT_CST_LOW (arg1
) == min_lo
+ 1)
12621 arg1
= const_binop (MINUS_EXPR
, arg1
, integer_one_node
, 0);
12622 return fold_build2 (NE_EXPR
, type
,
12623 fold_convert (TREE_TYPE (arg1
), arg0
),
12626 arg1
= const_binop (MINUS_EXPR
, arg1
, integer_one_node
, 0);
12627 return fold_build2 (EQ_EXPR
, type
,
12628 fold_convert (TREE_TYPE (arg1
), arg0
),
12634 else if (TREE_INT_CST_HIGH (arg1
) == signed_max_hi
12635 && TREE_INT_CST_LOW (arg1
) == signed_max_lo
12636 && TYPE_UNSIGNED (arg1_type
)
12637 /* We will flip the signedness of the comparison operator
12638 associated with the mode of arg1, so the sign bit is
12639 specified by this mode. Check that arg1 is the signed
12640 max associated with this sign bit. */
12641 && width
== GET_MODE_BITSIZE (TYPE_MODE (arg1_type
))
12642 /* signed_type does not work on pointer types. */
12643 && INTEGRAL_TYPE_P (arg1_type
))
12645 /* The following case also applies to X < signed_max+1
12646 and X >= signed_max+1 because previous transformations. */
12647 if (code
== LE_EXPR
|| code
== GT_EXPR
)
12650 st
= signed_type_for (TREE_TYPE (arg1
));
12651 return fold_build2 (code
== LE_EXPR
? GE_EXPR
: LT_EXPR
,
12652 type
, fold_convert (st
, arg0
),
12653 build_int_cst (st
, 0));
12659 /* If we are comparing an ABS_EXPR with a constant, we can
12660 convert all the cases into explicit comparisons, but they may
12661 well not be faster than doing the ABS and one comparison.
12662 But ABS (X) <= C is a range comparison, which becomes a subtraction
12663 and a comparison, and is probably faster. */
12664 if (code
== LE_EXPR
12665 && TREE_CODE (arg1
) == INTEGER_CST
12666 && TREE_CODE (arg0
) == ABS_EXPR
12667 && ! TREE_SIDE_EFFECTS (arg0
)
12668 && (0 != (tem
= negate_expr (arg1
)))
12669 && TREE_CODE (tem
) == INTEGER_CST
12670 && !TREE_OVERFLOW (tem
))
12671 return fold_build2 (TRUTH_ANDIF_EXPR
, type
,
12672 build2 (GE_EXPR
, type
,
12673 TREE_OPERAND (arg0
, 0), tem
),
12674 build2 (LE_EXPR
, type
,
12675 TREE_OPERAND (arg0
, 0), arg1
));
12677 /* Convert ABS_EXPR<x> >= 0 to true. */
12678 strict_overflow_p
= false;
12679 if (code
== GE_EXPR
12680 && (integer_zerop (arg1
)
12681 || (! HONOR_NANS (TYPE_MODE (TREE_TYPE (arg0
)))
12682 && real_zerop (arg1
)))
12683 && tree_expr_nonnegative_warnv_p (arg0
, &strict_overflow_p
))
12685 if (strict_overflow_p
)
12686 fold_overflow_warning (("assuming signed overflow does not occur "
12687 "when simplifying comparison of "
12688 "absolute value and zero"),
12689 WARN_STRICT_OVERFLOW_CONDITIONAL
);
12690 return omit_one_operand (type
, integer_one_node
, arg0
);
12693 /* Convert ABS_EXPR<x> < 0 to false. */
12694 strict_overflow_p
= false;
12695 if (code
== LT_EXPR
12696 && (integer_zerop (arg1
) || real_zerop (arg1
))
12697 && tree_expr_nonnegative_warnv_p (arg0
, &strict_overflow_p
))
12699 if (strict_overflow_p
)
12700 fold_overflow_warning (("assuming signed overflow does not occur "
12701 "when simplifying comparison of "
12702 "absolute value and zero"),
12703 WARN_STRICT_OVERFLOW_CONDITIONAL
);
12704 return omit_one_operand (type
, integer_zero_node
, arg0
);
12707 /* If X is unsigned, convert X < (1 << Y) into X >> Y == 0
12708 and similarly for >= into !=. */
12709 if ((code
== LT_EXPR
|| code
== GE_EXPR
)
12710 && TYPE_UNSIGNED (TREE_TYPE (arg0
))
12711 && TREE_CODE (arg1
) == LSHIFT_EXPR
12712 && integer_onep (TREE_OPERAND (arg1
, 0)))
12713 return build2 (code
== LT_EXPR
? EQ_EXPR
: NE_EXPR
, type
,
12714 build2 (RSHIFT_EXPR
, TREE_TYPE (arg0
), arg0
,
12715 TREE_OPERAND (arg1
, 1)),
12716 build_int_cst (TREE_TYPE (arg0
), 0));
12718 if ((code
== LT_EXPR
|| code
== GE_EXPR
)
12719 && TYPE_UNSIGNED (TREE_TYPE (arg0
))
12720 && (TREE_CODE (arg1
) == NOP_EXPR
12721 || TREE_CODE (arg1
) == CONVERT_EXPR
)
12722 && TREE_CODE (TREE_OPERAND (arg1
, 0)) == LSHIFT_EXPR
12723 && integer_onep (TREE_OPERAND (TREE_OPERAND (arg1
, 0), 0)))
12725 build2 (code
== LT_EXPR
? EQ_EXPR
: NE_EXPR
, type
,
12726 fold_convert (TREE_TYPE (arg0
),
12727 build2 (RSHIFT_EXPR
, TREE_TYPE (arg0
), arg0
,
12728 TREE_OPERAND (TREE_OPERAND (arg1
, 0),
12730 build_int_cst (TREE_TYPE (arg0
), 0));
12734 case UNORDERED_EXPR
:
12742 if (TREE_CODE (arg0
) == REAL_CST
&& TREE_CODE (arg1
) == REAL_CST
)
12744 t1
= fold_relational_const (code
, type
, arg0
, arg1
);
12745 if (t1
!= NULL_TREE
)
12749 /* If the first operand is NaN, the result is constant. */
12750 if (TREE_CODE (arg0
) == REAL_CST
12751 && REAL_VALUE_ISNAN (TREE_REAL_CST (arg0
))
12752 && (code
!= LTGT_EXPR
|| ! flag_trapping_math
))
12754 t1
= (code
== ORDERED_EXPR
|| code
== LTGT_EXPR
)
12755 ? integer_zero_node
12756 : integer_one_node
;
12757 return omit_one_operand (type
, t1
, arg1
);
12760 /* If the second operand is NaN, the result is constant. */
12761 if (TREE_CODE (arg1
) == REAL_CST
12762 && REAL_VALUE_ISNAN (TREE_REAL_CST (arg1
))
12763 && (code
!= LTGT_EXPR
|| ! flag_trapping_math
))
12765 t1
= (code
== ORDERED_EXPR
|| code
== LTGT_EXPR
)
12766 ? integer_zero_node
12767 : integer_one_node
;
12768 return omit_one_operand (type
, t1
, arg0
);
12771 /* Simplify unordered comparison of something with itself. */
12772 if ((code
== UNLE_EXPR
|| code
== UNGE_EXPR
|| code
== UNEQ_EXPR
)
12773 && operand_equal_p (arg0
, arg1
, 0))
12774 return constant_boolean_node (1, type
);
12776 if (code
== LTGT_EXPR
12777 && !flag_trapping_math
12778 && operand_equal_p (arg0
, arg1
, 0))
12779 return constant_boolean_node (0, type
);
12781 /* Fold (double)float1 CMP (double)float2 into float1 CMP float2. */
12783 tree targ0
= strip_float_extensions (arg0
);
12784 tree targ1
= strip_float_extensions (arg1
);
12785 tree newtype
= TREE_TYPE (targ0
);
12787 if (TYPE_PRECISION (TREE_TYPE (targ1
)) > TYPE_PRECISION (newtype
))
12788 newtype
= TREE_TYPE (targ1
);
12790 if (TYPE_PRECISION (newtype
) < TYPE_PRECISION (TREE_TYPE (arg0
)))
12791 return fold_build2 (code
, type
, fold_convert (newtype
, targ0
),
12792 fold_convert (newtype
, targ1
));
12797 case COMPOUND_EXPR
:
12798 /* When pedantic, a compound expression can be neither an lvalue
12799 nor an integer constant expression. */
12800 if (TREE_SIDE_EFFECTS (arg0
) || TREE_CONSTANT (arg1
))
12802 /* Don't let (0, 0) be null pointer constant. */
12803 tem
= integer_zerop (arg1
) ? build1 (NOP_EXPR
, type
, arg1
)
12804 : fold_convert (type
, arg1
);
12805 return pedantic_non_lvalue (tem
);
12808 if ((TREE_CODE (arg0
) == REAL_CST
12809 && TREE_CODE (arg1
) == REAL_CST
)
12810 || (TREE_CODE (arg0
) == INTEGER_CST
12811 && TREE_CODE (arg1
) == INTEGER_CST
))
12812 return build_complex (type
, arg0
, arg1
);
12816 /* An ASSERT_EXPR should never be passed to fold_binary. */
12817 gcc_unreachable ();
12821 } /* switch (code) */
12824 /* Callback for walk_tree, looking for LABEL_EXPR.
12825 Returns tree TP if it is LABEL_EXPR. Otherwise it returns NULL_TREE.
12826 Do not check the sub-tree of GOTO_EXPR. */
12829 contains_label_1 (tree
*tp
,
12830 int *walk_subtrees
,
12831 void *data ATTRIBUTE_UNUSED
)
12833 switch (TREE_CODE (*tp
))
12838 *walk_subtrees
= 0;
12845 /* Checks whether the sub-tree ST contains a label LABEL_EXPR which is
12846 accessible from outside the sub-tree. Returns NULL_TREE if no
12847 addressable label is found. */
12850 contains_label_p (tree st
)
12852 return (walk_tree (&st
, contains_label_1
, NULL
, NULL
) != NULL_TREE
);
12855 /* Fold a ternary expression of code CODE and type TYPE with operands
12856 OP0, OP1, and OP2. Return the folded expression if folding is
12857 successful. Otherwise, return NULL_TREE. */
12860 fold_ternary (enum tree_code code
, tree type
, tree op0
, tree op1
, tree op2
)
12863 tree arg0
= NULL_TREE
, arg1
= NULL_TREE
;
12864 enum tree_code_class kind
= TREE_CODE_CLASS (code
);
12866 gcc_assert (IS_EXPR_CODE_CLASS (kind
)
12867 && TREE_CODE_LENGTH (code
) == 3);
12869 /* Strip any conversions that don't change the mode. This is safe
12870 for every expression, except for a comparison expression because
12871 its signedness is derived from its operands. So, in the latter
12872 case, only strip conversions that don't change the signedness.
12874 Note that this is done as an internal manipulation within the
12875 constant folder, in order to find the simplest representation of
12876 the arguments so that their form can be studied. In any cases,
12877 the appropriate type conversions should be put back in the tree
12878 that will get out of the constant folder. */
12893 case COMPONENT_REF
:
12894 if (TREE_CODE (arg0
) == CONSTRUCTOR
12895 && ! type_contains_placeholder_p (TREE_TYPE (arg0
)))
12897 unsigned HOST_WIDE_INT idx
;
12899 FOR_EACH_CONSTRUCTOR_ELT (CONSTRUCTOR_ELTS (arg0
), idx
, field
, value
)
12906 /* Pedantic ANSI C says that a conditional expression is never an lvalue,
12907 so all simple results must be passed through pedantic_non_lvalue. */
12908 if (TREE_CODE (arg0
) == INTEGER_CST
)
12910 tree unused_op
= integer_zerop (arg0
) ? op1
: op2
;
12911 tem
= integer_zerop (arg0
) ? op2
: op1
;
12912 /* Only optimize constant conditions when the selected branch
12913 has the same type as the COND_EXPR. This avoids optimizing
12914 away "c ? x : throw", where the throw has a void type.
12915 Avoid throwing away that operand which contains label. */
12916 if ((!TREE_SIDE_EFFECTS (unused_op
)
12917 || !contains_label_p (unused_op
))
12918 && (! VOID_TYPE_P (TREE_TYPE (tem
))
12919 || VOID_TYPE_P (type
)))
12920 return pedantic_non_lvalue (tem
);
12923 if (operand_equal_p (arg1
, op2
, 0))
12924 return pedantic_omit_one_operand (type
, arg1
, arg0
);
12926 /* If we have A op B ? A : C, we may be able to convert this to a
12927 simpler expression, depending on the operation and the values
12928 of B and C. Signed zeros prevent all of these transformations,
12929 for reasons given above each one.
12931 Also try swapping the arguments and inverting the conditional. */
12932 if (COMPARISON_CLASS_P (arg0
)
12933 && operand_equal_for_comparison_p (TREE_OPERAND (arg0
, 0),
12934 arg1
, TREE_OPERAND (arg0
, 1))
12935 && !HONOR_SIGNED_ZEROS (TYPE_MODE (TREE_TYPE (arg1
))))
12937 tem
= fold_cond_expr_with_comparison (type
, arg0
, op1
, op2
);
12942 if (COMPARISON_CLASS_P (arg0
)
12943 && operand_equal_for_comparison_p (TREE_OPERAND (arg0
, 0),
12945 TREE_OPERAND (arg0
, 1))
12946 && !HONOR_SIGNED_ZEROS (TYPE_MODE (TREE_TYPE (op2
))))
12948 tem
= fold_truth_not_expr (arg0
);
12949 if (tem
&& COMPARISON_CLASS_P (tem
))
12951 tem
= fold_cond_expr_with_comparison (type
, tem
, op2
, op1
);
12957 /* If the second operand is simpler than the third, swap them
12958 since that produces better jump optimization results. */
12959 if (truth_value_p (TREE_CODE (arg0
))
12960 && tree_swap_operands_p (op1
, op2
, false))
12962 /* See if this can be inverted. If it can't, possibly because
12963 it was a floating-point inequality comparison, don't do
12965 tem
= fold_truth_not_expr (arg0
);
12967 return fold_build3 (code
, type
, tem
, op2
, op1
);
12970 /* Convert A ? 1 : 0 to simply A. */
12971 if (integer_onep (op1
)
12972 && integer_zerop (op2
)
12973 /* If we try to convert OP0 to our type, the
12974 call to fold will try to move the conversion inside
12975 a COND, which will recurse. In that case, the COND_EXPR
12976 is probably the best choice, so leave it alone. */
12977 && type
== TREE_TYPE (arg0
))
12978 return pedantic_non_lvalue (arg0
);
12980 /* Convert A ? 0 : 1 to !A. This prefers the use of NOT_EXPR
12981 over COND_EXPR in cases such as floating point comparisons. */
12982 if (integer_zerop (op1
)
12983 && integer_onep (op2
)
12984 && truth_value_p (TREE_CODE (arg0
)))
12985 return pedantic_non_lvalue (fold_convert (type
,
12986 invert_truthvalue (arg0
)));
12988 /* A < 0 ? <sign bit of A> : 0 is simply (A & <sign bit of A>). */
12989 if (TREE_CODE (arg0
) == LT_EXPR
12990 && integer_zerop (TREE_OPERAND (arg0
, 1))
12991 && integer_zerop (op2
)
12992 && (tem
= sign_bit_p (TREE_OPERAND (arg0
, 0), arg1
)))
12994 /* sign_bit_p only checks ARG1 bits within A's precision.
12995 If <sign bit of A> has wider type than A, bits outside
12996 of A's precision in <sign bit of A> need to be checked.
12997 If they are all 0, this optimization needs to be done
12998 in unsigned A's type, if they are all 1 in signed A's type,
12999 otherwise this can't be done. */
13000 if (TYPE_PRECISION (TREE_TYPE (tem
))
13001 < TYPE_PRECISION (TREE_TYPE (arg1
))
13002 && TYPE_PRECISION (TREE_TYPE (tem
))
13003 < TYPE_PRECISION (type
))
13005 unsigned HOST_WIDE_INT mask_lo
;
13006 HOST_WIDE_INT mask_hi
;
13007 int inner_width
, outer_width
;
13010 inner_width
= TYPE_PRECISION (TREE_TYPE (tem
));
13011 outer_width
= TYPE_PRECISION (TREE_TYPE (arg1
));
13012 if (outer_width
> TYPE_PRECISION (type
))
13013 outer_width
= TYPE_PRECISION (type
);
13015 if (outer_width
> HOST_BITS_PER_WIDE_INT
)
13017 mask_hi
= ((unsigned HOST_WIDE_INT
) -1
13018 >> (2 * HOST_BITS_PER_WIDE_INT
- outer_width
));
13024 mask_lo
= ((unsigned HOST_WIDE_INT
) -1
13025 >> (HOST_BITS_PER_WIDE_INT
- outer_width
));
13027 if (inner_width
> HOST_BITS_PER_WIDE_INT
)
13029 mask_hi
&= ~((unsigned HOST_WIDE_INT
) -1
13030 >> (HOST_BITS_PER_WIDE_INT
- inner_width
));
13034 mask_lo
&= ~((unsigned HOST_WIDE_INT
) -1
13035 >> (HOST_BITS_PER_WIDE_INT
- inner_width
));
13037 if ((TREE_INT_CST_HIGH (arg1
) & mask_hi
) == mask_hi
13038 && (TREE_INT_CST_LOW (arg1
) & mask_lo
) == mask_lo
)
13040 tem_type
= signed_type_for (TREE_TYPE (tem
));
13041 tem
= fold_convert (tem_type
, tem
);
13043 else if ((TREE_INT_CST_HIGH (arg1
) & mask_hi
) == 0
13044 && (TREE_INT_CST_LOW (arg1
) & mask_lo
) == 0)
13046 tem_type
= unsigned_type_for (TREE_TYPE (tem
));
13047 tem
= fold_convert (tem_type
, tem
);
13054 return fold_convert (type
,
13055 fold_build2 (BIT_AND_EXPR
,
13056 TREE_TYPE (tem
), tem
,
13057 fold_convert (TREE_TYPE (tem
),
13061 /* (A >> N) & 1 ? (1 << N) : 0 is simply A & (1 << N). A & 1 was
13062 already handled above. */
13063 if (TREE_CODE (arg0
) == BIT_AND_EXPR
13064 && integer_onep (TREE_OPERAND (arg0
, 1))
13065 && integer_zerop (op2
)
13066 && integer_pow2p (arg1
))
13068 tree tem
= TREE_OPERAND (arg0
, 0);
13070 if (TREE_CODE (tem
) == RSHIFT_EXPR
13071 && TREE_CODE (TREE_OPERAND (tem
, 1)) == INTEGER_CST
13072 && (unsigned HOST_WIDE_INT
) tree_log2 (arg1
) ==
13073 TREE_INT_CST_LOW (TREE_OPERAND (tem
, 1)))
13074 return fold_build2 (BIT_AND_EXPR
, type
,
13075 TREE_OPERAND (tem
, 0), arg1
);
13078 /* A & N ? N : 0 is simply A & N if N is a power of two. This
13079 is probably obsolete because the first operand should be a
13080 truth value (that's why we have the two cases above), but let's
13081 leave it in until we can confirm this for all front-ends. */
13082 if (integer_zerop (op2
)
13083 && TREE_CODE (arg0
) == NE_EXPR
13084 && integer_zerop (TREE_OPERAND (arg0
, 1))
13085 && integer_pow2p (arg1
)
13086 && TREE_CODE (TREE_OPERAND (arg0
, 0)) == BIT_AND_EXPR
13087 && operand_equal_p (TREE_OPERAND (TREE_OPERAND (arg0
, 0), 1),
13088 arg1
, OEP_ONLY_CONST
))
13089 return pedantic_non_lvalue (fold_convert (type
,
13090 TREE_OPERAND (arg0
, 0)));
13092 /* Convert A ? B : 0 into A && B if A and B are truth values. */
13093 if (integer_zerop (op2
)
13094 && truth_value_p (TREE_CODE (arg0
))
13095 && truth_value_p (TREE_CODE (arg1
)))
13096 return fold_build2 (TRUTH_ANDIF_EXPR
, type
,
13097 fold_convert (type
, arg0
),
13100 /* Convert A ? B : 1 into !A || B if A and B are truth values. */
13101 if (integer_onep (op2
)
13102 && truth_value_p (TREE_CODE (arg0
))
13103 && truth_value_p (TREE_CODE (arg1
)))
13105 /* Only perform transformation if ARG0 is easily inverted. */
13106 tem
= fold_truth_not_expr (arg0
);
13108 return fold_build2 (TRUTH_ORIF_EXPR
, type
,
13109 fold_convert (type
, tem
),
13113 /* Convert A ? 0 : B into !A && B if A and B are truth values. */
13114 if (integer_zerop (arg1
)
13115 && truth_value_p (TREE_CODE (arg0
))
13116 && truth_value_p (TREE_CODE (op2
)))
13118 /* Only perform transformation if ARG0 is easily inverted. */
13119 tem
= fold_truth_not_expr (arg0
);
13121 return fold_build2 (TRUTH_ANDIF_EXPR
, type
,
13122 fold_convert (type
, tem
),
13126 /* Convert A ? 1 : B into A || B if A and B are truth values. */
13127 if (integer_onep (arg1
)
13128 && truth_value_p (TREE_CODE (arg0
))
13129 && truth_value_p (TREE_CODE (op2
)))
13130 return fold_build2 (TRUTH_ORIF_EXPR
, type
,
13131 fold_convert (type
, arg0
),
13137 /* CALL_EXPRs used to be ternary exprs. Catch any mistaken uses
13138 of fold_ternary on them. */
13139 gcc_unreachable ();
13141 case BIT_FIELD_REF
:
13142 if ((TREE_CODE (arg0
) == VECTOR_CST
13143 || (TREE_CODE (arg0
) == CONSTRUCTOR
&& TREE_CONSTANT (arg0
)))
13144 && type
== TREE_TYPE (TREE_TYPE (arg0
))
13145 && host_integerp (arg1
, 1)
13146 && host_integerp (op2
, 1))
13148 unsigned HOST_WIDE_INT width
= tree_low_cst (arg1
, 1);
13149 unsigned HOST_WIDE_INT idx
= tree_low_cst (op2
, 1);
13152 && simple_cst_equal (arg1
, TYPE_SIZE (type
)) == 1
13153 && (idx
% width
) == 0
13154 && (idx
= idx
/ width
)
13155 < TYPE_VECTOR_SUBPARTS (TREE_TYPE (arg0
)))
13157 tree elements
= NULL_TREE
;
13159 if (TREE_CODE (arg0
) == VECTOR_CST
)
13160 elements
= TREE_VECTOR_CST_ELTS (arg0
);
13163 unsigned HOST_WIDE_INT idx
;
13166 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (arg0
), idx
, value
)
13167 elements
= tree_cons (NULL_TREE
, value
, elements
);
13169 while (idx
-- > 0 && elements
)
13170 elements
= TREE_CHAIN (elements
);
13172 return TREE_VALUE (elements
);
13174 return fold_convert (type
, integer_zero_node
);
13181 } /* switch (code) */
13184 /* Perform constant folding and related simplification of EXPR.
13185 The related simplifications include x*1 => x, x*0 => 0, etc.,
13186 and application of the associative law.
13187 NOP_EXPR conversions may be removed freely (as long as we
13188 are careful not to change the type of the overall expression).
13189 We cannot simplify through a CONVERT_EXPR, FIX_EXPR or FLOAT_EXPR,
13190 but we can constant-fold them if they have constant operands. */
13192 #ifdef ENABLE_FOLD_CHECKING
13193 # define fold(x) fold_1 (x)
13194 static tree
fold_1 (tree
);
13200 const tree t
= expr
;
13201 enum tree_code code
= TREE_CODE (t
);
13202 enum tree_code_class kind
= TREE_CODE_CLASS (code
);
13205 /* Return right away if a constant. */
13206 if (kind
== tcc_constant
)
13209 /* CALL_EXPR-like objects with variable numbers of operands are
13210 treated specially. */
13211 if (kind
== tcc_vl_exp
)
13213 if (code
== CALL_EXPR
)
13215 tem
= fold_call_expr (expr
, false);
13216 return tem
? tem
: expr
;
13221 if (IS_EXPR_CODE_CLASS (kind
)
13222 || IS_GIMPLE_STMT_CODE_CLASS (kind
))
13224 tree type
= TREE_TYPE (t
);
13225 tree op0
, op1
, op2
;
13227 switch (TREE_CODE_LENGTH (code
))
13230 op0
= TREE_OPERAND (t
, 0);
13231 tem
= fold_unary (code
, type
, op0
);
13232 return tem
? tem
: expr
;
13234 op0
= TREE_OPERAND (t
, 0);
13235 op1
= TREE_OPERAND (t
, 1);
13236 tem
= fold_binary (code
, type
, op0
, op1
);
13237 return tem
? tem
: expr
;
13239 op0
= TREE_OPERAND (t
, 0);
13240 op1
= TREE_OPERAND (t
, 1);
13241 op2
= TREE_OPERAND (t
, 2);
13242 tem
= fold_ternary (code
, type
, op0
, op1
, op2
);
13243 return tem
? tem
: expr
;
13252 return fold (DECL_INITIAL (t
));
13256 } /* switch (code) */
13259 #ifdef ENABLE_FOLD_CHECKING
13262 static void fold_checksum_tree (const_tree
, struct md5_ctx
*, htab_t
);
13263 static void fold_check_failed (const_tree
, const_tree
);
13264 void print_fold_checksum (const_tree
);
13266 /* When --enable-checking=fold, compute a digest of expr before
13267 and after actual fold call to see if fold did not accidentally
13268 change original expr. */
13274 struct md5_ctx ctx
;
13275 unsigned char checksum_before
[16], checksum_after
[16];
13278 ht
= htab_create (32, htab_hash_pointer
, htab_eq_pointer
, NULL
);
13279 md5_init_ctx (&ctx
);
13280 fold_checksum_tree (expr
, &ctx
, ht
);
13281 md5_finish_ctx (&ctx
, checksum_before
);
13284 ret
= fold_1 (expr
);
13286 md5_init_ctx (&ctx
);
13287 fold_checksum_tree (expr
, &ctx
, ht
);
13288 md5_finish_ctx (&ctx
, checksum_after
);
13291 if (memcmp (checksum_before
, checksum_after
, 16))
13292 fold_check_failed (expr
, ret
);
13298 print_fold_checksum (const_tree expr
)
13300 struct md5_ctx ctx
;
13301 unsigned char checksum
[16], cnt
;
13304 ht
= htab_create (32, htab_hash_pointer
, htab_eq_pointer
, NULL
);
13305 md5_init_ctx (&ctx
);
13306 fold_checksum_tree (expr
, &ctx
, ht
);
13307 md5_finish_ctx (&ctx
, checksum
);
13309 for (cnt
= 0; cnt
< 16; ++cnt
)
13310 fprintf (stderr
, "%02x", checksum
[cnt
]);
13311 putc ('\n', stderr
);
13315 fold_check_failed (const_tree expr ATTRIBUTE_UNUSED
, const_tree ret ATTRIBUTE_UNUSED
)
13317 internal_error ("fold check: original tree changed by fold");
13321 fold_checksum_tree (const_tree expr
, struct md5_ctx
*ctx
, htab_t ht
)
13324 enum tree_code code
;
13325 struct tree_function_decl buf
;
13330 gcc_assert ((sizeof (struct tree_exp
) + 5 * sizeof (tree
)
13331 <= sizeof (struct tree_function_decl
))
13332 && sizeof (struct tree_type
) <= sizeof (struct tree_function_decl
));
13335 slot
= (const void **) htab_find_slot (ht
, expr
, INSERT
);
13339 code
= TREE_CODE (expr
);
13340 if (TREE_CODE_CLASS (code
) == tcc_declaration
13341 && DECL_ASSEMBLER_NAME_SET_P (expr
))
13343 /* Allow DECL_ASSEMBLER_NAME to be modified. */
13344 memcpy ((char *) &buf
, expr
, tree_size (expr
));
13345 SET_DECL_ASSEMBLER_NAME ((tree
)&buf
, NULL
);
13346 expr
= (tree
) &buf
;
13348 else if (TREE_CODE_CLASS (code
) == tcc_type
13349 && (TYPE_POINTER_TO (expr
) || TYPE_REFERENCE_TO (expr
)
13350 || TYPE_CACHED_VALUES_P (expr
)
13351 || TYPE_CONTAINS_PLACEHOLDER_INTERNAL (expr
)))
13353 /* Allow these fields to be modified. */
13355 memcpy ((char *) &buf
, expr
, tree_size (expr
));
13356 expr
= tmp
= (tree
) &buf
;
13357 TYPE_CONTAINS_PLACEHOLDER_INTERNAL (tmp
) = 0;
13358 TYPE_POINTER_TO (tmp
) = NULL
;
13359 TYPE_REFERENCE_TO (tmp
) = NULL
;
13360 if (TYPE_CACHED_VALUES_P (tmp
))
13362 TYPE_CACHED_VALUES_P (tmp
) = 0;
13363 TYPE_CACHED_VALUES (tmp
) = NULL
;
13366 md5_process_bytes (expr
, tree_size (expr
), ctx
);
13367 fold_checksum_tree (TREE_TYPE (expr
), ctx
, ht
);
13368 if (TREE_CODE_CLASS (code
) != tcc_type
13369 && TREE_CODE_CLASS (code
) != tcc_declaration
13370 && code
!= TREE_LIST
13371 && code
!= SSA_NAME
)
13372 fold_checksum_tree (TREE_CHAIN (expr
), ctx
, ht
);
13373 switch (TREE_CODE_CLASS (code
))
13379 md5_process_bytes (TREE_STRING_POINTER (expr
),
13380 TREE_STRING_LENGTH (expr
), ctx
);
13383 fold_checksum_tree (TREE_REALPART (expr
), ctx
, ht
);
13384 fold_checksum_tree (TREE_IMAGPART (expr
), ctx
, ht
);
13387 fold_checksum_tree (TREE_VECTOR_CST_ELTS (expr
), ctx
, ht
);
13393 case tcc_exceptional
:
13397 fold_checksum_tree (TREE_PURPOSE (expr
), ctx
, ht
);
13398 fold_checksum_tree (TREE_VALUE (expr
), ctx
, ht
);
13399 expr
= TREE_CHAIN (expr
);
13400 goto recursive_label
;
13403 for (i
= 0; i
< TREE_VEC_LENGTH (expr
); ++i
)
13404 fold_checksum_tree (TREE_VEC_ELT (expr
, i
), ctx
, ht
);
13410 case tcc_expression
:
13411 case tcc_reference
:
13412 case tcc_comparison
:
13415 case tcc_statement
:
13417 len
= TREE_OPERAND_LENGTH (expr
);
13418 for (i
= 0; i
< len
; ++i
)
13419 fold_checksum_tree (TREE_OPERAND (expr
, i
), ctx
, ht
);
13421 case tcc_declaration
:
13422 fold_checksum_tree (DECL_NAME (expr
), ctx
, ht
);
13423 fold_checksum_tree (DECL_CONTEXT (expr
), ctx
, ht
);
13424 if (CODE_CONTAINS_STRUCT (TREE_CODE (expr
), TS_DECL_COMMON
))
13426 fold_checksum_tree (DECL_SIZE (expr
), ctx
, ht
);
13427 fold_checksum_tree (DECL_SIZE_UNIT (expr
), ctx
, ht
);
13428 fold_checksum_tree (DECL_INITIAL (expr
), ctx
, ht
);
13429 fold_checksum_tree (DECL_ABSTRACT_ORIGIN (expr
), ctx
, ht
);
13430 fold_checksum_tree (DECL_ATTRIBUTES (expr
), ctx
, ht
);
13432 if (CODE_CONTAINS_STRUCT (TREE_CODE (expr
), TS_DECL_WITH_VIS
))
13433 fold_checksum_tree (DECL_SECTION_NAME (expr
), ctx
, ht
);
13435 if (CODE_CONTAINS_STRUCT (TREE_CODE (expr
), TS_DECL_NON_COMMON
))
13437 fold_checksum_tree (DECL_VINDEX (expr
), ctx
, ht
);
13438 fold_checksum_tree (DECL_RESULT_FLD (expr
), ctx
, ht
);
13439 fold_checksum_tree (DECL_ARGUMENT_FLD (expr
), ctx
, ht
);
13443 if (TREE_CODE (expr
) == ENUMERAL_TYPE
)
13444 fold_checksum_tree (TYPE_VALUES (expr
), ctx
, ht
);
13445 fold_checksum_tree (TYPE_SIZE (expr
), ctx
, ht
);
13446 fold_checksum_tree (TYPE_SIZE_UNIT (expr
), ctx
, ht
);
13447 fold_checksum_tree (TYPE_ATTRIBUTES (expr
), ctx
, ht
);
13448 fold_checksum_tree (TYPE_NAME (expr
), ctx
, ht
);
13449 if (INTEGRAL_TYPE_P (expr
)
13450 || SCALAR_FLOAT_TYPE_P (expr
))
13452 fold_checksum_tree (TYPE_MIN_VALUE (expr
), ctx
, ht
);
13453 fold_checksum_tree (TYPE_MAX_VALUE (expr
), ctx
, ht
);
13455 fold_checksum_tree (TYPE_MAIN_VARIANT (expr
), ctx
, ht
);
13456 if (TREE_CODE (expr
) == RECORD_TYPE
13457 || TREE_CODE (expr
) == UNION_TYPE
13458 || TREE_CODE (expr
) == QUAL_UNION_TYPE
)
13459 fold_checksum_tree (TYPE_BINFO (expr
), ctx
, ht
);
13460 fold_checksum_tree (TYPE_CONTEXT (expr
), ctx
, ht
);
13467 /* Helper function for outputting the checksum of a tree T. When
13468 debugging with gdb, you can "define mynext" to be "next" followed
13469 by "call debug_fold_checksum (op0)", then just trace down till the
13473 debug_fold_checksum (const_tree t
)
13476 unsigned char checksum
[16];
13477 struct md5_ctx ctx
;
13478 htab_t ht
= htab_create (32, htab_hash_pointer
, htab_eq_pointer
, NULL
);
13480 md5_init_ctx (&ctx
);
13481 fold_checksum_tree (t
, &ctx
, ht
);
13482 md5_finish_ctx (&ctx
, checksum
);
13485 for (i
= 0; i
< 16; i
++)
13486 fprintf (stderr
, "%d ", checksum
[i
]);
13488 fprintf (stderr
, "\n");
13493 /* Fold a unary tree expression with code CODE of type TYPE with an
13494 operand OP0. Return a folded expression if successful. Otherwise,
13495 return a tree expression with code CODE of type TYPE with an
13499 fold_build1_stat (enum tree_code code
, tree type
, tree op0 MEM_STAT_DECL
)
13502 #ifdef ENABLE_FOLD_CHECKING
13503 unsigned char checksum_before
[16], checksum_after
[16];
13504 struct md5_ctx ctx
;
13507 ht
= htab_create (32, htab_hash_pointer
, htab_eq_pointer
, NULL
);
13508 md5_init_ctx (&ctx
);
13509 fold_checksum_tree (op0
, &ctx
, ht
);
13510 md5_finish_ctx (&ctx
, checksum_before
);
13514 tem
= fold_unary (code
, type
, op0
);
13516 tem
= build1_stat (code
, type
, op0 PASS_MEM_STAT
);
13518 #ifdef ENABLE_FOLD_CHECKING
13519 md5_init_ctx (&ctx
);
13520 fold_checksum_tree (op0
, &ctx
, ht
);
13521 md5_finish_ctx (&ctx
, checksum_after
);
13524 if (memcmp (checksum_before
, checksum_after
, 16))
13525 fold_check_failed (op0
, tem
);
13530 /* Fold a binary tree expression with code CODE of type TYPE with
13531 operands OP0 and OP1. Return a folded expression if successful.
13532 Otherwise, return a tree expression with code CODE of type TYPE
13533 with operands OP0 and OP1. */
13536 fold_build2_stat (enum tree_code code
, tree type
, tree op0
, tree op1
13540 #ifdef ENABLE_FOLD_CHECKING
13541 unsigned char checksum_before_op0
[16],
13542 checksum_before_op1
[16],
13543 checksum_after_op0
[16],
13544 checksum_after_op1
[16];
13545 struct md5_ctx ctx
;
13548 ht
= htab_create (32, htab_hash_pointer
, htab_eq_pointer
, NULL
);
13549 md5_init_ctx (&ctx
);
13550 fold_checksum_tree (op0
, &ctx
, ht
);
13551 md5_finish_ctx (&ctx
, checksum_before_op0
);
13554 md5_init_ctx (&ctx
);
13555 fold_checksum_tree (op1
, &ctx
, ht
);
13556 md5_finish_ctx (&ctx
, checksum_before_op1
);
13560 tem
= fold_binary (code
, type
, op0
, op1
);
13562 tem
= build2_stat (code
, type
, op0
, op1 PASS_MEM_STAT
);
13564 #ifdef ENABLE_FOLD_CHECKING
13565 md5_init_ctx (&ctx
);
13566 fold_checksum_tree (op0
, &ctx
, ht
);
13567 md5_finish_ctx (&ctx
, checksum_after_op0
);
13570 if (memcmp (checksum_before_op0
, checksum_after_op0
, 16))
13571 fold_check_failed (op0
, tem
);
13573 md5_init_ctx (&ctx
);
13574 fold_checksum_tree (op1
, &ctx
, ht
);
13575 md5_finish_ctx (&ctx
, checksum_after_op1
);
13578 if (memcmp (checksum_before_op1
, checksum_after_op1
, 16))
13579 fold_check_failed (op1
, tem
);
13584 /* Fold a ternary tree expression with code CODE of type TYPE with
13585 operands OP0, OP1, and OP2. Return a folded expression if
13586 successful. Otherwise, return a tree expression with code CODE of
13587 type TYPE with operands OP0, OP1, and OP2. */
13590 fold_build3_stat (enum tree_code code
, tree type
, tree op0
, tree op1
, tree op2
13594 #ifdef ENABLE_FOLD_CHECKING
13595 unsigned char checksum_before_op0
[16],
13596 checksum_before_op1
[16],
13597 checksum_before_op2
[16],
13598 checksum_after_op0
[16],
13599 checksum_after_op1
[16],
13600 checksum_after_op2
[16];
13601 struct md5_ctx ctx
;
13604 ht
= htab_create (32, htab_hash_pointer
, htab_eq_pointer
, NULL
);
13605 md5_init_ctx (&ctx
);
13606 fold_checksum_tree (op0
, &ctx
, ht
);
13607 md5_finish_ctx (&ctx
, checksum_before_op0
);
13610 md5_init_ctx (&ctx
);
13611 fold_checksum_tree (op1
, &ctx
, ht
);
13612 md5_finish_ctx (&ctx
, checksum_before_op1
);
13615 md5_init_ctx (&ctx
);
13616 fold_checksum_tree (op2
, &ctx
, ht
);
13617 md5_finish_ctx (&ctx
, checksum_before_op2
);
13621 gcc_assert (TREE_CODE_CLASS (code
) != tcc_vl_exp
);
13622 tem
= fold_ternary (code
, type
, op0
, op1
, op2
);
13624 tem
= build3_stat (code
, type
, op0
, op1
, op2 PASS_MEM_STAT
);
13626 #ifdef ENABLE_FOLD_CHECKING
13627 md5_init_ctx (&ctx
);
13628 fold_checksum_tree (op0
, &ctx
, ht
);
13629 md5_finish_ctx (&ctx
, checksum_after_op0
);
13632 if (memcmp (checksum_before_op0
, checksum_after_op0
, 16))
13633 fold_check_failed (op0
, tem
);
13635 md5_init_ctx (&ctx
);
13636 fold_checksum_tree (op1
, &ctx
, ht
);
13637 md5_finish_ctx (&ctx
, checksum_after_op1
);
13640 if (memcmp (checksum_before_op1
, checksum_after_op1
, 16))
13641 fold_check_failed (op1
, tem
);
13643 md5_init_ctx (&ctx
);
13644 fold_checksum_tree (op2
, &ctx
, ht
);
13645 md5_finish_ctx (&ctx
, checksum_after_op2
);
13648 if (memcmp (checksum_before_op2
, checksum_after_op2
, 16))
13649 fold_check_failed (op2
, tem
);
13654 /* Fold a CALL_EXPR expression of type TYPE with operands FN and NARGS
13655 arguments in ARGARRAY, and a null static chain.
13656 Return a folded expression if successful. Otherwise, return a CALL_EXPR
13657 of type TYPE from the given operands as constructed by build_call_array. */
13660 fold_build_call_array (tree type
, tree fn
, int nargs
, tree
*argarray
)
13663 #ifdef ENABLE_FOLD_CHECKING
13664 unsigned char checksum_before_fn
[16],
13665 checksum_before_arglist
[16],
13666 checksum_after_fn
[16],
13667 checksum_after_arglist
[16];
13668 struct md5_ctx ctx
;
13672 ht
= htab_create (32, htab_hash_pointer
, htab_eq_pointer
, NULL
);
13673 md5_init_ctx (&ctx
);
13674 fold_checksum_tree (fn
, &ctx
, ht
);
13675 md5_finish_ctx (&ctx
, checksum_before_fn
);
13678 md5_init_ctx (&ctx
);
13679 for (i
= 0; i
< nargs
; i
++)
13680 fold_checksum_tree (argarray
[i
], &ctx
, ht
);
13681 md5_finish_ctx (&ctx
, checksum_before_arglist
);
13685 tem
= fold_builtin_call_array (type
, fn
, nargs
, argarray
);
13687 #ifdef ENABLE_FOLD_CHECKING
13688 md5_init_ctx (&ctx
);
13689 fold_checksum_tree (fn
, &ctx
, ht
);
13690 md5_finish_ctx (&ctx
, checksum_after_fn
);
13693 if (memcmp (checksum_before_fn
, checksum_after_fn
, 16))
13694 fold_check_failed (fn
, tem
);
13696 md5_init_ctx (&ctx
);
13697 for (i
= 0; i
< nargs
; i
++)
13698 fold_checksum_tree (argarray
[i
], &ctx
, ht
);
13699 md5_finish_ctx (&ctx
, checksum_after_arglist
);
13702 if (memcmp (checksum_before_arglist
, checksum_after_arglist
, 16))
13703 fold_check_failed (NULL_TREE
, tem
);
13708 /* Perform constant folding and related simplification of initializer
13709 expression EXPR. These behave identically to "fold_buildN" but ignore
13710 potential run-time traps and exceptions that fold must preserve. */
13712 #define START_FOLD_INIT \
13713 int saved_signaling_nans = flag_signaling_nans;\
13714 int saved_trapping_math = flag_trapping_math;\
13715 int saved_rounding_math = flag_rounding_math;\
13716 int saved_trapv = flag_trapv;\
13717 int saved_folding_initializer = folding_initializer;\
13718 flag_signaling_nans = 0;\
13719 flag_trapping_math = 0;\
13720 flag_rounding_math = 0;\
13722 folding_initializer = 1;
13724 #define END_FOLD_INIT \
13725 flag_signaling_nans = saved_signaling_nans;\
13726 flag_trapping_math = saved_trapping_math;\
13727 flag_rounding_math = saved_rounding_math;\
13728 flag_trapv = saved_trapv;\
13729 folding_initializer = saved_folding_initializer;
13732 fold_build1_initializer (enum tree_code code
, tree type
, tree op
)
13737 result
= fold_build1 (code
, type
, op
);
13744 fold_build2_initializer (enum tree_code code
, tree type
, tree op0
, tree op1
)
13749 result
= fold_build2 (code
, type
, op0
, op1
);
13756 fold_build3_initializer (enum tree_code code
, tree type
, tree op0
, tree op1
,
13762 result
= fold_build3 (code
, type
, op0
, op1
, op2
);
13769 fold_build_call_array_initializer (tree type
, tree fn
,
13770 int nargs
, tree
*argarray
)
13775 result
= fold_build_call_array (type
, fn
, nargs
, argarray
);
13781 #undef START_FOLD_INIT
13782 #undef END_FOLD_INIT
13784 /* Determine if first argument is a multiple of second argument. Return 0 if
13785 it is not, or we cannot easily determined it to be.
13787 An example of the sort of thing we care about (at this point; this routine
13788 could surely be made more general, and expanded to do what the *_DIV_EXPR's
13789 fold cases do now) is discovering that
13791 SAVE_EXPR (I) * SAVE_EXPR (J * 8)
13797 when we know that the two SAVE_EXPR (J * 8) nodes are the same node.
13799 This code also handles discovering that
13801 SAVE_EXPR (I) * SAVE_EXPR (J * 8)
13803 is a multiple of 8 so we don't have to worry about dealing with a
13804 possible remainder.
13806 Note that we *look* inside a SAVE_EXPR only to determine how it was
13807 calculated; it is not safe for fold to do much of anything else with the
13808 internals of a SAVE_EXPR, since it cannot know when it will be evaluated
13809 at run time. For example, the latter example above *cannot* be implemented
13810 as SAVE_EXPR (I) * J or any variant thereof, since the value of J at
13811 evaluation time of the original SAVE_EXPR is not necessarily the same at
13812 the time the new expression is evaluated. The only optimization of this
13813 sort that would be valid is changing
13815 SAVE_EXPR (I) * SAVE_EXPR (SAVE_EXPR (J) * 8)
13819 SAVE_EXPR (I) * SAVE_EXPR (J)
13821 (where the same SAVE_EXPR (J) is used in the original and the
13822 transformed version). */
13825 multiple_of_p (tree type
, const_tree top
, const_tree bottom
)
13827 if (operand_equal_p (top
, bottom
, 0))
13830 if (TREE_CODE (type
) != INTEGER_TYPE
)
13833 switch (TREE_CODE (top
))
13836 /* Bitwise and provides a power of two multiple. If the mask is
13837 a multiple of BOTTOM then TOP is a multiple of BOTTOM. */
13838 if (!integer_pow2p (bottom
))
13843 return (multiple_of_p (type
, TREE_OPERAND (top
, 0), bottom
)
13844 || multiple_of_p (type
, TREE_OPERAND (top
, 1), bottom
));
13848 return (multiple_of_p (type
, TREE_OPERAND (top
, 0), bottom
)
13849 && multiple_of_p (type
, TREE_OPERAND (top
, 1), bottom
));
13852 if (TREE_CODE (TREE_OPERAND (top
, 1)) == INTEGER_CST
)
13856 op1
= TREE_OPERAND (top
, 1);
13857 /* const_binop may not detect overflow correctly,
13858 so check for it explicitly here. */
13859 if (TYPE_PRECISION (TREE_TYPE (size_one_node
))
13860 > TREE_INT_CST_LOW (op1
)
13861 && TREE_INT_CST_HIGH (op1
) == 0
13862 && 0 != (t1
= fold_convert (type
,
13863 const_binop (LSHIFT_EXPR
,
13866 && !TREE_OVERFLOW (t1
))
13867 return multiple_of_p (type
, t1
, bottom
);
13872 /* Can't handle conversions from non-integral or wider integral type. */
13873 if ((TREE_CODE (TREE_TYPE (TREE_OPERAND (top
, 0))) != INTEGER_TYPE
)
13874 || (TYPE_PRECISION (type
)
13875 < TYPE_PRECISION (TREE_TYPE (TREE_OPERAND (top
, 0)))))
13878 /* .. fall through ... */
13881 return multiple_of_p (type
, TREE_OPERAND (top
, 0), bottom
);
13884 if (TREE_CODE (bottom
) != INTEGER_CST
13885 || integer_zerop (bottom
)
13886 || (TYPE_UNSIGNED (type
)
13887 && (tree_int_cst_sgn (top
) < 0
13888 || tree_int_cst_sgn (bottom
) < 0)))
13890 return integer_zerop (int_const_binop (TRUNC_MOD_EXPR
,
13898 /* Return true if `t' is known to be non-negative. If the return
13899 value is based on the assumption that signed overflow is undefined,
13900 set *STRICT_OVERFLOW_P to true; otherwise, don't change
13901 *STRICT_OVERFLOW_P. */
13904 tree_expr_nonnegative_warnv_p (tree t
, bool *strict_overflow_p
)
13906 if (t
== error_mark_node
)
13909 if (TYPE_UNSIGNED (TREE_TYPE (t
)))
13912 switch (TREE_CODE (t
))
13915 /* Query VRP to see if it has recorded any information about
13916 the range of this object. */
13917 return ssa_name_nonnegative_p (t
);
13920 /* We can't return 1 if flag_wrapv is set because
13921 ABS_EXPR<INT_MIN> = INT_MIN. */
13922 if (!INTEGRAL_TYPE_P (TREE_TYPE (t
)))
13924 if (TYPE_OVERFLOW_UNDEFINED (TREE_TYPE (t
)))
13926 *strict_overflow_p
= true;
13932 return tree_int_cst_sgn (t
) >= 0;
13935 return ! REAL_VALUE_NEGATIVE (TREE_REAL_CST (t
));
13938 return ! FIXED_VALUE_NEGATIVE (TREE_FIXED_CST (t
));
13940 case POINTER_PLUS_EXPR
:
13942 if (FLOAT_TYPE_P (TREE_TYPE (t
)))
13943 return (tree_expr_nonnegative_warnv_p (TREE_OPERAND (t
, 0),
13945 && tree_expr_nonnegative_warnv_p (TREE_OPERAND (t
, 1),
13946 strict_overflow_p
));
13948 /* zero_extend(x) + zero_extend(y) is non-negative if x and y are
13949 both unsigned and at least 2 bits shorter than the result. */
13950 if (TREE_CODE (TREE_TYPE (t
)) == INTEGER_TYPE
13951 && TREE_CODE (TREE_OPERAND (t
, 0)) == NOP_EXPR
13952 && TREE_CODE (TREE_OPERAND (t
, 1)) == NOP_EXPR
)
13954 tree inner1
= TREE_TYPE (TREE_OPERAND (TREE_OPERAND (t
, 0), 0));
13955 tree inner2
= TREE_TYPE (TREE_OPERAND (TREE_OPERAND (t
, 1), 0));
13956 if (TREE_CODE (inner1
) == INTEGER_TYPE
&& TYPE_UNSIGNED (inner1
)
13957 && TREE_CODE (inner2
) == INTEGER_TYPE
&& TYPE_UNSIGNED (inner2
))
13959 unsigned int prec
= MAX (TYPE_PRECISION (inner1
),
13960 TYPE_PRECISION (inner2
)) + 1;
13961 return prec
< TYPE_PRECISION (TREE_TYPE (t
));
13967 if (FLOAT_TYPE_P (TREE_TYPE (t
)))
13969 /* x * x for floating point x is always non-negative. */
13970 if (operand_equal_p (TREE_OPERAND (t
, 0), TREE_OPERAND (t
, 1), 0))
13972 return (tree_expr_nonnegative_warnv_p (TREE_OPERAND (t
, 0),
13974 && tree_expr_nonnegative_warnv_p (TREE_OPERAND (t
, 1),
13975 strict_overflow_p
));
13978 /* zero_extend(x) * zero_extend(y) is non-negative if x and y are
13979 both unsigned and their total bits is shorter than the result. */
13980 if (TREE_CODE (TREE_TYPE (t
)) == INTEGER_TYPE
13981 && TREE_CODE (TREE_OPERAND (t
, 0)) == NOP_EXPR
13982 && TREE_CODE (TREE_OPERAND (t
, 1)) == NOP_EXPR
)
13984 tree inner1
= TREE_TYPE (TREE_OPERAND (TREE_OPERAND (t
, 0), 0));
13985 tree inner2
= TREE_TYPE (TREE_OPERAND (TREE_OPERAND (t
, 1), 0));
13986 if (TREE_CODE (inner1
) == INTEGER_TYPE
&& TYPE_UNSIGNED (inner1
)
13987 && TREE_CODE (inner2
) == INTEGER_TYPE
&& TYPE_UNSIGNED (inner2
))
13988 return TYPE_PRECISION (inner1
) + TYPE_PRECISION (inner2
)
13989 < TYPE_PRECISION (TREE_TYPE (t
));
13995 return (tree_expr_nonnegative_warnv_p (TREE_OPERAND (t
, 0),
13997 || tree_expr_nonnegative_warnv_p (TREE_OPERAND (t
, 1),
13998 strict_overflow_p
));
14004 case TRUNC_DIV_EXPR
:
14005 case CEIL_DIV_EXPR
:
14006 case FLOOR_DIV_EXPR
:
14007 case ROUND_DIV_EXPR
:
14008 return (tree_expr_nonnegative_warnv_p (TREE_OPERAND (t
, 0),
14010 && tree_expr_nonnegative_warnv_p (TREE_OPERAND (t
, 1),
14011 strict_overflow_p
));
14013 case TRUNC_MOD_EXPR
:
14014 case CEIL_MOD_EXPR
:
14015 case FLOOR_MOD_EXPR
:
14016 case ROUND_MOD_EXPR
:
14018 case NON_LVALUE_EXPR
:
14020 case FIX_TRUNC_EXPR
:
14021 return tree_expr_nonnegative_warnv_p (TREE_OPERAND (t
, 0),
14022 strict_overflow_p
);
14024 case COMPOUND_EXPR
:
14026 case GIMPLE_MODIFY_STMT
:
14027 return tree_expr_nonnegative_warnv_p (GENERIC_TREE_OPERAND (t
, 1),
14028 strict_overflow_p
);
14031 return tree_expr_nonnegative_warnv_p (expr_last (TREE_OPERAND (t
, 1)),
14032 strict_overflow_p
);
14035 return (tree_expr_nonnegative_warnv_p (TREE_OPERAND (t
, 1),
14037 && tree_expr_nonnegative_warnv_p (TREE_OPERAND (t
, 2),
14038 strict_overflow_p
));
14042 tree inner_type
= TREE_TYPE (TREE_OPERAND (t
, 0));
14043 tree outer_type
= TREE_TYPE (t
);
14045 if (TREE_CODE (outer_type
) == REAL_TYPE
)
14047 if (TREE_CODE (inner_type
) == REAL_TYPE
)
14048 return tree_expr_nonnegative_warnv_p (TREE_OPERAND (t
, 0),
14049 strict_overflow_p
);
14050 if (TREE_CODE (inner_type
) == INTEGER_TYPE
)
14052 if (TYPE_UNSIGNED (inner_type
))
14054 return tree_expr_nonnegative_warnv_p (TREE_OPERAND (t
, 0),
14055 strict_overflow_p
);
14058 else if (TREE_CODE (outer_type
) == INTEGER_TYPE
)
14060 if (TREE_CODE (inner_type
) == REAL_TYPE
)
14061 return tree_expr_nonnegative_warnv_p (TREE_OPERAND (t
,0),
14062 strict_overflow_p
);
14063 if (TREE_CODE (inner_type
) == INTEGER_TYPE
)
14064 return TYPE_PRECISION (inner_type
) < TYPE_PRECISION (outer_type
)
14065 && TYPE_UNSIGNED (inner_type
);
14072 tree temp
= TARGET_EXPR_SLOT (t
);
14073 t
= TARGET_EXPR_INITIAL (t
);
14075 /* If the initializer is non-void, then it's a normal expression
14076 that will be assigned to the slot. */
14077 if (!VOID_TYPE_P (t
))
14078 return tree_expr_nonnegative_warnv_p (t
, strict_overflow_p
);
14080 /* Otherwise, the initializer sets the slot in some way. One common
14081 way is an assignment statement at the end of the initializer. */
14084 if (TREE_CODE (t
) == BIND_EXPR
)
14085 t
= expr_last (BIND_EXPR_BODY (t
));
14086 else if (TREE_CODE (t
) == TRY_FINALLY_EXPR
14087 || TREE_CODE (t
) == TRY_CATCH_EXPR
)
14088 t
= expr_last (TREE_OPERAND (t
, 0));
14089 else if (TREE_CODE (t
) == STATEMENT_LIST
)
14094 if ((TREE_CODE (t
) == MODIFY_EXPR
14095 || TREE_CODE (t
) == GIMPLE_MODIFY_STMT
)
14096 && GENERIC_TREE_OPERAND (t
, 0) == temp
)
14097 return tree_expr_nonnegative_warnv_p (GENERIC_TREE_OPERAND (t
, 1),
14098 strict_overflow_p
);
14105 tree fndecl
= get_callee_fndecl (t
);
14106 if (fndecl
&& DECL_BUILT_IN_CLASS (fndecl
) == BUILT_IN_NORMAL
)
14107 switch (DECL_FUNCTION_CODE (fndecl
))
14109 CASE_FLT_FN (BUILT_IN_ACOS
):
14110 CASE_FLT_FN (BUILT_IN_ACOSH
):
14111 CASE_FLT_FN (BUILT_IN_CABS
):
14112 CASE_FLT_FN (BUILT_IN_COSH
):
14113 CASE_FLT_FN (BUILT_IN_ERFC
):
14114 CASE_FLT_FN (BUILT_IN_EXP
):
14115 CASE_FLT_FN (BUILT_IN_EXP10
):
14116 CASE_FLT_FN (BUILT_IN_EXP2
):
14117 CASE_FLT_FN (BUILT_IN_FABS
):
14118 CASE_FLT_FN (BUILT_IN_FDIM
):
14119 CASE_FLT_FN (BUILT_IN_HYPOT
):
14120 CASE_FLT_FN (BUILT_IN_POW10
):
14121 CASE_INT_FN (BUILT_IN_FFS
):
14122 CASE_INT_FN (BUILT_IN_PARITY
):
14123 CASE_INT_FN (BUILT_IN_POPCOUNT
):
14124 case BUILT_IN_BSWAP32
:
14125 case BUILT_IN_BSWAP64
:
14129 CASE_FLT_FN (BUILT_IN_SQRT
):
14130 /* sqrt(-0.0) is -0.0. */
14131 if (!HONOR_SIGNED_ZEROS (TYPE_MODE (TREE_TYPE (t
))))
14133 return tree_expr_nonnegative_warnv_p (CALL_EXPR_ARG (t
, 0),
14134 strict_overflow_p
);
14136 CASE_FLT_FN (BUILT_IN_ASINH
):
14137 CASE_FLT_FN (BUILT_IN_ATAN
):
14138 CASE_FLT_FN (BUILT_IN_ATANH
):
14139 CASE_FLT_FN (BUILT_IN_CBRT
):
14140 CASE_FLT_FN (BUILT_IN_CEIL
):
14141 CASE_FLT_FN (BUILT_IN_ERF
):
14142 CASE_FLT_FN (BUILT_IN_EXPM1
):
14143 CASE_FLT_FN (BUILT_IN_FLOOR
):
14144 CASE_FLT_FN (BUILT_IN_FMOD
):
14145 CASE_FLT_FN (BUILT_IN_FREXP
):
14146 CASE_FLT_FN (BUILT_IN_LCEIL
):
14147 CASE_FLT_FN (BUILT_IN_LDEXP
):
14148 CASE_FLT_FN (BUILT_IN_LFLOOR
):
14149 CASE_FLT_FN (BUILT_IN_LLCEIL
):
14150 CASE_FLT_FN (BUILT_IN_LLFLOOR
):
14151 CASE_FLT_FN (BUILT_IN_LLRINT
):
14152 CASE_FLT_FN (BUILT_IN_LLROUND
):
14153 CASE_FLT_FN (BUILT_IN_LRINT
):
14154 CASE_FLT_FN (BUILT_IN_LROUND
):
14155 CASE_FLT_FN (BUILT_IN_MODF
):
14156 CASE_FLT_FN (BUILT_IN_NEARBYINT
):
14157 CASE_FLT_FN (BUILT_IN_RINT
):
14158 CASE_FLT_FN (BUILT_IN_ROUND
):
14159 CASE_FLT_FN (BUILT_IN_SCALB
):
14160 CASE_FLT_FN (BUILT_IN_SCALBLN
):
14161 CASE_FLT_FN (BUILT_IN_SCALBN
):
14162 CASE_FLT_FN (BUILT_IN_SIGNBIT
):
14163 CASE_FLT_FN (BUILT_IN_SIGNIFICAND
):
14164 CASE_FLT_FN (BUILT_IN_SINH
):
14165 CASE_FLT_FN (BUILT_IN_TANH
):
14166 CASE_FLT_FN (BUILT_IN_TRUNC
):
14167 /* True if the 1st argument is nonnegative. */
14168 return tree_expr_nonnegative_warnv_p (CALL_EXPR_ARG (t
, 0),
14169 strict_overflow_p
);
14171 CASE_FLT_FN (BUILT_IN_FMAX
):
14172 /* True if the 1st OR 2nd arguments are nonnegative. */
14173 return (tree_expr_nonnegative_warnv_p (CALL_EXPR_ARG (t
, 0),
14175 || (tree_expr_nonnegative_warnv_p (CALL_EXPR_ARG (t
, 1),
14176 strict_overflow_p
)));
14178 CASE_FLT_FN (BUILT_IN_FMIN
):
14179 /* True if the 1st AND 2nd arguments are nonnegative. */
14180 return (tree_expr_nonnegative_warnv_p (CALL_EXPR_ARG (t
, 0),
14182 && (tree_expr_nonnegative_warnv_p (CALL_EXPR_ARG (t
, 1),
14183 strict_overflow_p
)));
14185 CASE_FLT_FN (BUILT_IN_COPYSIGN
):
14186 /* True if the 2nd argument is nonnegative. */
14187 return tree_expr_nonnegative_warnv_p (CALL_EXPR_ARG (t
, 1),
14188 strict_overflow_p
);
14190 CASE_FLT_FN (BUILT_IN_POWI
):
14191 /* True if the 1st argument is nonnegative or the second
14192 argument is an even integer. */
14193 if (TREE_CODE (CALL_EXPR_ARG (t
, 1)) == INTEGER_CST
)
14195 tree arg1
= CALL_EXPR_ARG (t
, 1);
14196 if ((TREE_INT_CST_LOW (arg1
) & 1) == 0)
14199 return tree_expr_nonnegative_warnv_p (CALL_EXPR_ARG (t
, 0),
14200 strict_overflow_p
);
14202 CASE_FLT_FN (BUILT_IN_POW
):
14203 /* True if the 1st argument is nonnegative or the second
14204 argument is an even integer valued real. */
14205 if (TREE_CODE (CALL_EXPR_ARG (t
, 1)) == REAL_CST
)
14210 c
= TREE_REAL_CST (CALL_EXPR_ARG (t
, 1));
14211 n
= real_to_integer (&c
);
14214 REAL_VALUE_TYPE cint
;
14215 real_from_integer (&cint
, VOIDmode
, n
,
14216 n
< 0 ? -1 : 0, 0);
14217 if (real_identical (&c
, &cint
))
14221 return tree_expr_nonnegative_warnv_p (CALL_EXPR_ARG (t
, 0),
14222 strict_overflow_p
);
14229 /* ... fall through ... */
14233 tree type
= TREE_TYPE (t
);
14234 if ((TYPE_PRECISION (type
) != 1 || TYPE_UNSIGNED (type
))
14235 && truth_value_p (TREE_CODE (t
)))
14236 /* Truth values evaluate to 0 or 1, which is nonnegative unless we
14237 have a signed:1 type (where the value is -1 and 0). */
14242 /* We don't know sign of `t', so be conservative and return false. */
14246 /* Return true if `t' is known to be non-negative. Handle warnings
14247 about undefined signed overflow. */
14250 tree_expr_nonnegative_p (tree t
)
14252 bool ret
, strict_overflow_p
;
14254 strict_overflow_p
= false;
14255 ret
= tree_expr_nonnegative_warnv_p (t
, &strict_overflow_p
);
14256 if (strict_overflow_p
)
14257 fold_overflow_warning (("assuming signed overflow does not occur when "
14258 "determining that expression is always "
14260 WARN_STRICT_OVERFLOW_MISC
);
14264 /* Return true when T is an address and is known to be nonzero.
14265 For floating point we further ensure that T is not denormal.
14266 Similar logic is present in nonzero_address in rtlanal.h.
14268 If the return value is based on the assumption that signed overflow
14269 is undefined, set *STRICT_OVERFLOW_P to true; otherwise, don't
14270 change *STRICT_OVERFLOW_P. */
14273 tree_expr_nonzero_warnv_p (tree t
, bool *strict_overflow_p
)
14275 tree type
= TREE_TYPE (t
);
14276 bool sub_strict_overflow_p
;
14278 /* Doing something useful for floating point would need more work. */
14279 if (!INTEGRAL_TYPE_P (type
) && !POINTER_TYPE_P (type
))
14282 switch (TREE_CODE (t
))
14285 /* Query VRP to see if it has recorded any information about
14286 the range of this object. */
14287 return ssa_name_nonzero_p (t
);
14290 return tree_expr_nonzero_warnv_p (TREE_OPERAND (t
, 0),
14291 strict_overflow_p
);
14294 return !integer_zerop (t
);
14296 case POINTER_PLUS_EXPR
:
14298 if (TYPE_OVERFLOW_UNDEFINED (type
))
14300 /* With the presence of negative values it is hard
14301 to say something. */
14302 sub_strict_overflow_p
= false;
14303 if (!tree_expr_nonnegative_warnv_p (TREE_OPERAND (t
, 0),
14304 &sub_strict_overflow_p
)
14305 || !tree_expr_nonnegative_warnv_p (TREE_OPERAND (t
, 1),
14306 &sub_strict_overflow_p
))
14308 /* One of operands must be positive and the other non-negative. */
14309 /* We don't set *STRICT_OVERFLOW_P here: even if this value
14310 overflows, on a twos-complement machine the sum of two
14311 nonnegative numbers can never be zero. */
14312 return (tree_expr_nonzero_warnv_p (TREE_OPERAND (t
, 0),
14314 || tree_expr_nonzero_warnv_p (TREE_OPERAND (t
, 1),
14315 strict_overflow_p
));
14320 if (TYPE_OVERFLOW_UNDEFINED (type
))
14322 if (tree_expr_nonzero_warnv_p (TREE_OPERAND (t
, 0),
14324 && tree_expr_nonzero_warnv_p (TREE_OPERAND (t
, 1),
14325 strict_overflow_p
))
14327 *strict_overflow_p
= true;
14335 tree inner_type
= TREE_TYPE (TREE_OPERAND (t
, 0));
14336 tree outer_type
= TREE_TYPE (t
);
14338 return (TYPE_PRECISION (outer_type
) >= TYPE_PRECISION (inner_type
)
14339 && tree_expr_nonzero_warnv_p (TREE_OPERAND (t
, 0),
14340 strict_overflow_p
));
14346 tree base
= get_base_address (TREE_OPERAND (t
, 0));
14351 /* Weak declarations may link to NULL. */
14352 if (VAR_OR_FUNCTION_DECL_P (base
))
14353 return !DECL_WEAK (base
);
14355 /* Constants are never weak. */
14356 if (CONSTANT_CLASS_P (base
))
14363 sub_strict_overflow_p
= false;
14364 if (tree_expr_nonzero_warnv_p (TREE_OPERAND (t
, 1),
14365 &sub_strict_overflow_p
)
14366 && tree_expr_nonzero_warnv_p (TREE_OPERAND (t
, 2),
14367 &sub_strict_overflow_p
))
14369 if (sub_strict_overflow_p
)
14370 *strict_overflow_p
= true;
14376 sub_strict_overflow_p
= false;
14377 if (tree_expr_nonzero_warnv_p (TREE_OPERAND (t
, 0),
14378 &sub_strict_overflow_p
)
14379 && tree_expr_nonzero_warnv_p (TREE_OPERAND (t
, 1),
14380 &sub_strict_overflow_p
))
14382 if (sub_strict_overflow_p
)
14383 *strict_overflow_p
= true;
14388 sub_strict_overflow_p
= false;
14389 if (tree_expr_nonzero_warnv_p (TREE_OPERAND (t
, 0),
14390 &sub_strict_overflow_p
))
14392 if (sub_strict_overflow_p
)
14393 *strict_overflow_p
= true;
14395 /* When both operands are nonzero, then MAX must be too. */
14396 if (tree_expr_nonzero_warnv_p (TREE_OPERAND (t
, 1),
14397 strict_overflow_p
))
14400 /* MAX where operand 0 is positive is positive. */
14401 return tree_expr_nonnegative_warnv_p (TREE_OPERAND (t
, 0),
14402 strict_overflow_p
);
14404 /* MAX where operand 1 is positive is positive. */
14405 else if (tree_expr_nonzero_warnv_p (TREE_OPERAND (t
, 1),
14406 &sub_strict_overflow_p
)
14407 && tree_expr_nonnegative_warnv_p (TREE_OPERAND (t
, 1),
14408 &sub_strict_overflow_p
))
14410 if (sub_strict_overflow_p
)
14411 *strict_overflow_p
= true;
14416 case COMPOUND_EXPR
:
14418 case GIMPLE_MODIFY_STMT
:
14420 return tree_expr_nonzero_warnv_p (GENERIC_TREE_OPERAND (t
, 1),
14421 strict_overflow_p
);
14424 case NON_LVALUE_EXPR
:
14425 return tree_expr_nonzero_warnv_p (TREE_OPERAND (t
, 0),
14426 strict_overflow_p
);
14429 return (tree_expr_nonzero_warnv_p (TREE_OPERAND (t
, 1),
14431 || tree_expr_nonzero_warnv_p (TREE_OPERAND (t
, 0),
14432 strict_overflow_p
));
14435 return alloca_call_p (t
);
14443 /* Return true when T is an address and is known to be nonzero.
14444 Handle warnings about undefined signed overflow. */
14447 tree_expr_nonzero_p (tree t
)
14449 bool ret
, strict_overflow_p
;
14451 strict_overflow_p
= false;
14452 ret
= tree_expr_nonzero_warnv_p (t
, &strict_overflow_p
);
14453 if (strict_overflow_p
)
14454 fold_overflow_warning (("assuming signed overflow does not occur when "
14455 "determining that expression is always "
14457 WARN_STRICT_OVERFLOW_MISC
);
14461 /* Given the components of a binary expression CODE, TYPE, OP0 and OP1,
14462 attempt to fold the expression to a constant without modifying TYPE,
14465 If the expression could be simplified to a constant, then return
14466 the constant. If the expression would not be simplified to a
14467 constant, then return NULL_TREE. */
14470 fold_binary_to_constant (enum tree_code code
, tree type
, tree op0
, tree op1
)
14472 tree tem
= fold_binary (code
, type
, op0
, op1
);
14473 return (tem
&& TREE_CONSTANT (tem
)) ? tem
: NULL_TREE
;
14476 /* Given the components of a unary expression CODE, TYPE and OP0,
14477 attempt to fold the expression to a constant without modifying
14480 If the expression could be simplified to a constant, then return
14481 the constant. If the expression would not be simplified to a
14482 constant, then return NULL_TREE. */
14485 fold_unary_to_constant (enum tree_code code
, tree type
, tree op0
)
14487 tree tem
= fold_unary (code
, type
, op0
);
14488 return (tem
&& TREE_CONSTANT (tem
)) ? tem
: NULL_TREE
;
14491 /* If EXP represents referencing an element in a constant string
14492 (either via pointer arithmetic or array indexing), return the
14493 tree representing the value accessed, otherwise return NULL. */
14496 fold_read_from_constant_string (tree exp
)
14498 if ((TREE_CODE (exp
) == INDIRECT_REF
14499 || TREE_CODE (exp
) == ARRAY_REF
)
14500 && TREE_CODE (TREE_TYPE (exp
)) == INTEGER_TYPE
)
14502 tree exp1
= TREE_OPERAND (exp
, 0);
14506 if (TREE_CODE (exp
) == INDIRECT_REF
)
14507 string
= string_constant (exp1
, &index
);
14510 tree low_bound
= array_ref_low_bound (exp
);
14511 index
= fold_convert (sizetype
, TREE_OPERAND (exp
, 1));
14513 /* Optimize the special-case of a zero lower bound.
14515 We convert the low_bound to sizetype to avoid some problems
14516 with constant folding. (E.g. suppose the lower bound is 1,
14517 and its mode is QI. Without the conversion,l (ARRAY
14518 +(INDEX-(unsigned char)1)) becomes ((ARRAY+(-(unsigned char)1))
14519 +INDEX), which becomes (ARRAY+255+INDEX). Opps!) */
14520 if (! integer_zerop (low_bound
))
14521 index
= size_diffop (index
, fold_convert (sizetype
, low_bound
));
14527 && TYPE_MODE (TREE_TYPE (exp
)) == TYPE_MODE (TREE_TYPE (TREE_TYPE (string
)))
14528 && TREE_CODE (string
) == STRING_CST
14529 && TREE_CODE (index
) == INTEGER_CST
14530 && compare_tree_int (index
, TREE_STRING_LENGTH (string
)) < 0
14531 && (GET_MODE_CLASS (TYPE_MODE (TREE_TYPE (TREE_TYPE (string
))))
14533 && (GET_MODE_SIZE (TYPE_MODE (TREE_TYPE (TREE_TYPE (string
)))) == 1))
14534 return build_int_cst_type (TREE_TYPE (exp
),
14535 (TREE_STRING_POINTER (string
)
14536 [TREE_INT_CST_LOW (index
)]));
14541 /* Return the tree for neg (ARG0) when ARG0 is known to be either
14542 an integer constant, real, or fixed-point constant.
14544 TYPE is the type of the result. */
14547 fold_negate_const (tree arg0
, tree type
)
14549 tree t
= NULL_TREE
;
14551 switch (TREE_CODE (arg0
))
14555 unsigned HOST_WIDE_INT low
;
14556 HOST_WIDE_INT high
;
14557 int overflow
= neg_double (TREE_INT_CST_LOW (arg0
),
14558 TREE_INT_CST_HIGH (arg0
),
14560 t
= force_fit_type_double (type
, low
, high
, 1,
14561 (overflow
| TREE_OVERFLOW (arg0
))
14562 && !TYPE_UNSIGNED (type
));
14567 t
= build_real (type
, REAL_VALUE_NEGATE (TREE_REAL_CST (arg0
)));
14572 FIXED_VALUE_TYPE f
;
14573 bool overflow_p
= fixed_arithmetic (&f
, NEGATE_EXPR
,
14574 &(TREE_FIXED_CST (arg0
)), NULL
,
14575 TYPE_SATURATING (type
));
14576 t
= build_fixed (type
, f
);
14577 /* Propagate overflow flags. */
14578 if (overflow_p
| TREE_OVERFLOW (arg0
))
14580 TREE_OVERFLOW (t
) = 1;
14581 TREE_CONSTANT_OVERFLOW (t
) = 1;
14583 else if (TREE_CONSTANT_OVERFLOW (arg0
))
14584 TREE_CONSTANT_OVERFLOW (t
) = 1;
14589 gcc_unreachable ();
14595 /* Return the tree for abs (ARG0) when ARG0 is known to be either
14596 an integer constant or real constant.
14598 TYPE is the type of the result. */
14601 fold_abs_const (tree arg0
, tree type
)
14603 tree t
= NULL_TREE
;
14605 switch (TREE_CODE (arg0
))
14608 /* If the value is unsigned, then the absolute value is
14609 the same as the ordinary value. */
14610 if (TYPE_UNSIGNED (type
))
14612 /* Similarly, if the value is non-negative. */
14613 else if (INT_CST_LT (integer_minus_one_node
, arg0
))
14615 /* If the value is negative, then the absolute value is
14619 unsigned HOST_WIDE_INT low
;
14620 HOST_WIDE_INT high
;
14621 int overflow
= neg_double (TREE_INT_CST_LOW (arg0
),
14622 TREE_INT_CST_HIGH (arg0
),
14624 t
= force_fit_type_double (type
, low
, high
, -1,
14625 overflow
| TREE_OVERFLOW (arg0
));
14630 if (REAL_VALUE_NEGATIVE (TREE_REAL_CST (arg0
)))
14631 t
= build_real (type
, REAL_VALUE_NEGATE (TREE_REAL_CST (arg0
)));
14637 gcc_unreachable ();
14643 /* Return the tree for not (ARG0) when ARG0 is known to be an integer
14644 constant. TYPE is the type of the result. */
14647 fold_not_const (tree arg0
, tree type
)
14649 tree t
= NULL_TREE
;
14651 gcc_assert (TREE_CODE (arg0
) == INTEGER_CST
);
14653 t
= force_fit_type_double (type
, ~TREE_INT_CST_LOW (arg0
),
14654 ~TREE_INT_CST_HIGH (arg0
), 0,
14655 TREE_OVERFLOW (arg0
));
14660 /* Given CODE, a relational operator, the target type, TYPE and two
14661 constant operands OP0 and OP1, return the result of the
14662 relational operation. If the result is not a compile time
14663 constant, then return NULL_TREE. */
14666 fold_relational_const (enum tree_code code
, tree type
, tree op0
, tree op1
)
14668 int result
, invert
;
14670 /* From here on, the only cases we handle are when the result is
14671 known to be a constant. */
14673 if (TREE_CODE (op0
) == REAL_CST
&& TREE_CODE (op1
) == REAL_CST
)
14675 const REAL_VALUE_TYPE
*c0
= TREE_REAL_CST_PTR (op0
);
14676 const REAL_VALUE_TYPE
*c1
= TREE_REAL_CST_PTR (op1
);
14678 /* Handle the cases where either operand is a NaN. */
14679 if (real_isnan (c0
) || real_isnan (c1
))
14689 case UNORDERED_EXPR
:
14703 if (flag_trapping_math
)
14709 gcc_unreachable ();
14712 return constant_boolean_node (result
, type
);
14715 return constant_boolean_node (real_compare (code
, c0
, c1
), type
);
14718 if (TREE_CODE (op0
) == FIXED_CST
&& TREE_CODE (op1
) == FIXED_CST
)
14720 const FIXED_VALUE_TYPE
*c0
= TREE_FIXED_CST_PTR (op0
);
14721 const FIXED_VALUE_TYPE
*c1
= TREE_FIXED_CST_PTR (op1
);
14722 return constant_boolean_node (fixed_compare (code
, c0
, c1
), type
);
14725 /* Handle equality/inequality of complex constants. */
14726 if (TREE_CODE (op0
) == COMPLEX_CST
&& TREE_CODE (op1
) == COMPLEX_CST
)
14728 tree rcond
= fold_relational_const (code
, type
,
14729 TREE_REALPART (op0
),
14730 TREE_REALPART (op1
));
14731 tree icond
= fold_relational_const (code
, type
,
14732 TREE_IMAGPART (op0
),
14733 TREE_IMAGPART (op1
));
14734 if (code
== EQ_EXPR
)
14735 return fold_build2 (TRUTH_ANDIF_EXPR
, type
, rcond
, icond
);
14736 else if (code
== NE_EXPR
)
14737 return fold_build2 (TRUTH_ORIF_EXPR
, type
, rcond
, icond
);
14742 /* From here on we only handle LT, LE, GT, GE, EQ and NE.
14744 To compute GT, swap the arguments and do LT.
14745 To compute GE, do LT and invert the result.
14746 To compute LE, swap the arguments, do LT and invert the result.
14747 To compute NE, do EQ and invert the result.
14749 Therefore, the code below must handle only EQ and LT. */
14751 if (code
== LE_EXPR
|| code
== GT_EXPR
)
14756 code
= swap_tree_comparison (code
);
14759 /* Note that it is safe to invert for real values here because we
14760 have already handled the one case that it matters. */
14763 if (code
== NE_EXPR
|| code
== GE_EXPR
)
14766 code
= invert_tree_comparison (code
, false);
14769 /* Compute a result for LT or EQ if args permit;
14770 Otherwise return T. */
14771 if (TREE_CODE (op0
) == INTEGER_CST
&& TREE_CODE (op1
) == INTEGER_CST
)
14773 if (code
== EQ_EXPR
)
14774 result
= tree_int_cst_equal (op0
, op1
);
14775 else if (TYPE_UNSIGNED (TREE_TYPE (op0
)))
14776 result
= INT_CST_LT_UNSIGNED (op0
, op1
);
14778 result
= INT_CST_LT (op0
, op1
);
14785 return constant_boolean_node (result
, type
);
14788 /* If necessary, return a CLEANUP_POINT_EXPR for EXPR with the
14789 indicated TYPE. If no CLEANUP_POINT_EXPR is necessary, return EXPR
14793 fold_build_cleanup_point_expr (tree type
, tree expr
)
14795 /* If the expression does not have side effects then we don't have to wrap
14796 it with a cleanup point expression. */
14797 if (!TREE_SIDE_EFFECTS (expr
))
14800 /* If the expression is a return, check to see if the expression inside the
14801 return has no side effects or the right hand side of the modify expression
14802 inside the return. If either don't have side effects set we don't need to
14803 wrap the expression in a cleanup point expression. Note we don't check the
14804 left hand side of the modify because it should always be a return decl. */
14805 if (TREE_CODE (expr
) == RETURN_EXPR
)
14807 tree op
= TREE_OPERAND (expr
, 0);
14808 if (!op
|| !TREE_SIDE_EFFECTS (op
))
14810 op
= TREE_OPERAND (op
, 1);
14811 if (!TREE_SIDE_EFFECTS (op
))
14815 return build1 (CLEANUP_POINT_EXPR
, type
, expr
);
14818 /* Given a pointer value OP0 and a type TYPE, return a simplified version
14819 of an indirection through OP0, or NULL_TREE if no simplification is
14823 fold_indirect_ref_1 (tree type
, tree op0
)
14829 subtype
= TREE_TYPE (sub
);
14830 if (!POINTER_TYPE_P (subtype
))
14833 if (TREE_CODE (sub
) == ADDR_EXPR
)
14835 tree op
= TREE_OPERAND (sub
, 0);
14836 tree optype
= TREE_TYPE (op
);
14837 /* *&CONST_DECL -> to the value of the const decl. */
14838 if (TREE_CODE (op
) == CONST_DECL
)
14839 return DECL_INITIAL (op
);
14840 /* *&p => p; make sure to handle *&"str"[cst] here. */
14841 if (type
== optype
)
14843 tree fop
= fold_read_from_constant_string (op
);
14849 /* *(foo *)&fooarray => fooarray[0] */
14850 else if (TREE_CODE (optype
) == ARRAY_TYPE
14851 && type
== TREE_TYPE (optype
))
14853 tree type_domain
= TYPE_DOMAIN (optype
);
14854 tree min_val
= size_zero_node
;
14855 if (type_domain
&& TYPE_MIN_VALUE (type_domain
))
14856 min_val
= TYPE_MIN_VALUE (type_domain
);
14857 return build4 (ARRAY_REF
, type
, op
, min_val
, NULL_TREE
, NULL_TREE
);
14859 /* *(foo *)&complexfoo => __real__ complexfoo */
14860 else if (TREE_CODE (optype
) == COMPLEX_TYPE
14861 && type
== TREE_TYPE (optype
))
14862 return fold_build1 (REALPART_EXPR
, type
, op
);
14863 /* *(foo *)&vectorfoo => BIT_FIELD_REF<vectorfoo,...> */
14864 else if (TREE_CODE (optype
) == VECTOR_TYPE
14865 && type
== TREE_TYPE (optype
))
14867 tree part_width
= TYPE_SIZE (type
);
14868 tree index
= bitsize_int (0);
14869 return fold_build3 (BIT_FIELD_REF
, type
, op
, part_width
, index
);
14873 /* ((foo*)&complexfoo)[1] => __imag__ complexfoo */
14874 if (TREE_CODE (sub
) == POINTER_PLUS_EXPR
14875 && TREE_CODE (TREE_OPERAND (sub
, 1)) == INTEGER_CST
)
14877 tree op00
= TREE_OPERAND (sub
, 0);
14878 tree op01
= TREE_OPERAND (sub
, 1);
14882 op00type
= TREE_TYPE (op00
);
14883 if (TREE_CODE (op00
) == ADDR_EXPR
14884 && TREE_CODE (TREE_TYPE (op00type
)) == COMPLEX_TYPE
14885 && type
== TREE_TYPE (TREE_TYPE (op00type
)))
14887 tree size
= TYPE_SIZE_UNIT (type
);
14888 if (tree_int_cst_equal (size
, op01
))
14889 return fold_build1 (IMAGPART_EXPR
, type
, TREE_OPERAND (op00
, 0));
14893 /* *(foo *)fooarrptr => (*fooarrptr)[0] */
14894 if (TREE_CODE (TREE_TYPE (subtype
)) == ARRAY_TYPE
14895 && type
== TREE_TYPE (TREE_TYPE (subtype
)))
14898 tree min_val
= size_zero_node
;
14899 sub
= build_fold_indirect_ref (sub
);
14900 type_domain
= TYPE_DOMAIN (TREE_TYPE (sub
));
14901 if (type_domain
&& TYPE_MIN_VALUE (type_domain
))
14902 min_val
= TYPE_MIN_VALUE (type_domain
);
14903 return build4 (ARRAY_REF
, type
, sub
, min_val
, NULL_TREE
, NULL_TREE
);
14909 /* Builds an expression for an indirection through T, simplifying some
14913 build_fold_indirect_ref (tree t
)
14915 tree type
= TREE_TYPE (TREE_TYPE (t
));
14916 tree sub
= fold_indirect_ref_1 (type
, t
);
14921 return build1 (INDIRECT_REF
, type
, t
);
14924 /* Given an INDIRECT_REF T, return either T or a simplified version. */
14927 fold_indirect_ref (tree t
)
14929 tree sub
= fold_indirect_ref_1 (TREE_TYPE (t
), TREE_OPERAND (t
, 0));
14937 /* Strip non-trapping, non-side-effecting tree nodes from an expression
14938 whose result is ignored. The type of the returned tree need not be
14939 the same as the original expression. */
14942 fold_ignored_result (tree t
)
14944 if (!TREE_SIDE_EFFECTS (t
))
14945 return integer_zero_node
;
14948 switch (TREE_CODE_CLASS (TREE_CODE (t
)))
14951 t
= TREE_OPERAND (t
, 0);
14955 case tcc_comparison
:
14956 if (!TREE_SIDE_EFFECTS (TREE_OPERAND (t
, 1)))
14957 t
= TREE_OPERAND (t
, 0);
14958 else if (!TREE_SIDE_EFFECTS (TREE_OPERAND (t
, 0)))
14959 t
= TREE_OPERAND (t
, 1);
14964 case tcc_expression
:
14965 switch (TREE_CODE (t
))
14967 case COMPOUND_EXPR
:
14968 if (TREE_SIDE_EFFECTS (TREE_OPERAND (t
, 1)))
14970 t
= TREE_OPERAND (t
, 0);
14974 if (TREE_SIDE_EFFECTS (TREE_OPERAND (t
, 1))
14975 || TREE_SIDE_EFFECTS (TREE_OPERAND (t
, 2)))
14977 t
= TREE_OPERAND (t
, 0);
14990 /* Return the value of VALUE, rounded up to a multiple of DIVISOR.
14991 This can only be applied to objects of a sizetype. */
14994 round_up (tree value
, int divisor
)
14996 tree div
= NULL_TREE
;
14998 gcc_assert (divisor
> 0);
15002 /* See if VALUE is already a multiple of DIVISOR. If so, we don't
15003 have to do anything. Only do this when we are not given a const,
15004 because in that case, this check is more expensive than just
15006 if (TREE_CODE (value
) != INTEGER_CST
)
15008 div
= build_int_cst (TREE_TYPE (value
), divisor
);
15010 if (multiple_of_p (TREE_TYPE (value
), value
, div
))
15014 /* If divisor is a power of two, simplify this to bit manipulation. */
15015 if (divisor
== (divisor
& -divisor
))
15017 if (TREE_CODE (value
) == INTEGER_CST
)
15019 unsigned HOST_WIDE_INT low
= TREE_INT_CST_LOW (value
);
15020 unsigned HOST_WIDE_INT high
;
15023 if ((low
& (divisor
- 1)) == 0)
15026 overflow_p
= TREE_OVERFLOW (value
);
15027 high
= TREE_INT_CST_HIGH (value
);
15028 low
&= ~(divisor
- 1);
15037 return force_fit_type_double (TREE_TYPE (value
), low
, high
,
15044 t
= build_int_cst (TREE_TYPE (value
), divisor
- 1);
15045 value
= size_binop (PLUS_EXPR
, value
, t
);
15046 t
= build_int_cst (TREE_TYPE (value
), -divisor
);
15047 value
= size_binop (BIT_AND_EXPR
, value
, t
);
15053 div
= build_int_cst (TREE_TYPE (value
), divisor
);
15054 value
= size_binop (CEIL_DIV_EXPR
, value
, div
);
15055 value
= size_binop (MULT_EXPR
, value
, div
);
15061 /* Likewise, but round down. */
15064 round_down (tree value
, int divisor
)
15066 tree div
= NULL_TREE
;
15068 gcc_assert (divisor
> 0);
15072 /* See if VALUE is already a multiple of DIVISOR. If so, we don't
15073 have to do anything. Only do this when we are not given a const,
15074 because in that case, this check is more expensive than just
15076 if (TREE_CODE (value
) != INTEGER_CST
)
15078 div
= build_int_cst (TREE_TYPE (value
), divisor
);
15080 if (multiple_of_p (TREE_TYPE (value
), value
, div
))
15084 /* If divisor is a power of two, simplify this to bit manipulation. */
15085 if (divisor
== (divisor
& -divisor
))
15089 t
= build_int_cst (TREE_TYPE (value
), -divisor
);
15090 value
= size_binop (BIT_AND_EXPR
, value
, t
);
15095 div
= build_int_cst (TREE_TYPE (value
), divisor
);
15096 value
= size_binop (FLOOR_DIV_EXPR
, value
, div
);
15097 value
= size_binop (MULT_EXPR
, value
, div
);
15103 /* Returns the pointer to the base of the object addressed by EXP and
15104 extracts the information about the offset of the access, storing it
15105 to PBITPOS and POFFSET. */
15108 split_address_to_core_and_offset (tree exp
,
15109 HOST_WIDE_INT
*pbitpos
, tree
*poffset
)
15112 enum machine_mode mode
;
15113 int unsignedp
, volatilep
;
15114 HOST_WIDE_INT bitsize
;
15116 if (TREE_CODE (exp
) == ADDR_EXPR
)
15118 core
= get_inner_reference (TREE_OPERAND (exp
, 0), &bitsize
, pbitpos
,
15119 poffset
, &mode
, &unsignedp
, &volatilep
,
15121 core
= fold_addr_expr (core
);
15127 *poffset
= NULL_TREE
;
15133 /* Returns true if addresses of E1 and E2 differ by a constant, false
15134 otherwise. If they do, E1 - E2 is stored in *DIFF. */
15137 ptr_difference_const (tree e1
, tree e2
, HOST_WIDE_INT
*diff
)
15140 HOST_WIDE_INT bitpos1
, bitpos2
;
15141 tree toffset1
, toffset2
, tdiff
, type
;
15143 core1
= split_address_to_core_and_offset (e1
, &bitpos1
, &toffset1
);
15144 core2
= split_address_to_core_and_offset (e2
, &bitpos2
, &toffset2
);
15146 if (bitpos1
% BITS_PER_UNIT
!= 0
15147 || bitpos2
% BITS_PER_UNIT
!= 0
15148 || !operand_equal_p (core1
, core2
, 0))
15151 if (toffset1
&& toffset2
)
15153 type
= TREE_TYPE (toffset1
);
15154 if (type
!= TREE_TYPE (toffset2
))
15155 toffset2
= fold_convert (type
, toffset2
);
15157 tdiff
= fold_build2 (MINUS_EXPR
, type
, toffset1
, toffset2
);
15158 if (!cst_and_fits_in_hwi (tdiff
))
15161 *diff
= int_cst_value (tdiff
);
15163 else if (toffset1
|| toffset2
)
15165 /* If only one of the offsets is non-constant, the difference cannot
15172 *diff
+= (bitpos1
- bitpos2
) / BITS_PER_UNIT
;
15176 /* Simplify the floating point expression EXP when the sign of the
15177 result is not significant. Return NULL_TREE if no simplification
15181 fold_strip_sign_ops (tree exp
)
15185 switch (TREE_CODE (exp
))
15189 arg0
= fold_strip_sign_ops (TREE_OPERAND (exp
, 0));
15190 return arg0
? arg0
: TREE_OPERAND (exp
, 0);
15194 if (HONOR_SIGN_DEPENDENT_ROUNDING (TYPE_MODE (TREE_TYPE (exp
))))
15196 arg0
= fold_strip_sign_ops (TREE_OPERAND (exp
, 0));
15197 arg1
= fold_strip_sign_ops (TREE_OPERAND (exp
, 1));
15198 if (arg0
!= NULL_TREE
|| arg1
!= NULL_TREE
)
15199 return fold_build2 (TREE_CODE (exp
), TREE_TYPE (exp
),
15200 arg0
? arg0
: TREE_OPERAND (exp
, 0),
15201 arg1
? arg1
: TREE_OPERAND (exp
, 1));
15204 case COMPOUND_EXPR
:
15205 arg0
= TREE_OPERAND (exp
, 0);
15206 arg1
= fold_strip_sign_ops (TREE_OPERAND (exp
, 1));
15208 return fold_build2 (COMPOUND_EXPR
, TREE_TYPE (exp
), arg0
, arg1
);
15212 arg0
= fold_strip_sign_ops (TREE_OPERAND (exp
, 1));
15213 arg1
= fold_strip_sign_ops (TREE_OPERAND (exp
, 2));
15215 return fold_build3 (COND_EXPR
, TREE_TYPE (exp
), TREE_OPERAND (exp
, 0),
15216 arg0
? arg0
: TREE_OPERAND (exp
, 1),
15217 arg1
? arg1
: TREE_OPERAND (exp
, 2));
15222 const enum built_in_function fcode
= builtin_mathfn_code (exp
);
15225 CASE_FLT_FN (BUILT_IN_COPYSIGN
):
15226 /* Strip copysign function call, return the 1st argument. */
15227 arg0
= CALL_EXPR_ARG (exp
, 0);
15228 arg1
= CALL_EXPR_ARG (exp
, 1);
15229 return omit_one_operand (TREE_TYPE (exp
), arg0
, arg1
);
15232 /* Strip sign ops from the argument of "odd" math functions. */
15233 if (negate_mathfn_p (fcode
))
15235 arg0
= fold_strip_sign_ops (CALL_EXPR_ARG (exp
, 0));
15237 return build_call_expr (get_callee_fndecl (exp
), 1, arg0
);