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 Free Software Foundation, Inc.
5 This file is part of GCC.
7 GCC is free software; you can redistribute it and/or modify it under
8 the terms of the GNU General Public License as published by the Free
9 Software Foundation; either version 2, or (at your option) any later
12 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
13 WARRANTY; without even the implied warranty of MERCHANTABILITY or
14 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
17 You should have received a copy of the GNU General Public License
18 along with GCC; see the file COPYING. If not, write to the Free
19 Software Foundation, 59 Temple Place - Suite 330, Boston, MA
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
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 takes a constant, an overflowable flag and prior
43 overflow indicators. It forces the value to fit the type and sets
44 TREE_OVERFLOW and TREE_CONSTANT_OVERFLOW as appropriate. */
48 #include "coretypes.h"
59 #include "langhooks.h"
62 /* The following constants represent a bit based encoding of GCC's
63 comparison operators. This encoding simplifies transformations
64 on relational comparison operators, such as AND and OR. */
65 enum comparison_code
{
84 static void encode (HOST_WIDE_INT
*, unsigned HOST_WIDE_INT
, HOST_WIDE_INT
);
85 static void decode (HOST_WIDE_INT
*, unsigned HOST_WIDE_INT
*, HOST_WIDE_INT
*);
86 static bool negate_mathfn_p (enum built_in_function
);
87 static bool negate_expr_p (tree
);
88 static tree
negate_expr (tree
);
89 static tree
split_tree (tree
, enum tree_code
, tree
*, tree
*, tree
*, int);
90 static tree
associate_trees (tree
, tree
, enum tree_code
, tree
);
91 static tree
const_binop (enum tree_code
, tree
, tree
, int);
92 static enum tree_code
invert_tree_comparison (enum tree_code
, bool);
93 static enum comparison_code
comparison_to_compcode (enum tree_code
);
94 static enum tree_code
compcode_to_comparison (enum comparison_code
);
95 static tree
combine_comparisons (enum tree_code
, enum tree_code
,
96 enum tree_code
, tree
, tree
, tree
);
97 static int truth_value_p (enum tree_code
);
98 static int operand_equal_for_comparison_p (tree
, tree
, tree
);
99 static int twoval_comparison_p (tree
, tree
*, tree
*, int *);
100 static tree
eval_subst (tree
, tree
, tree
, tree
, tree
);
101 static tree
pedantic_omit_one_operand (tree
, tree
, tree
);
102 static tree
distribute_bit_expr (enum tree_code
, tree
, tree
, tree
);
103 static tree
make_bit_field_ref (tree
, tree
, int, int, int);
104 static tree
optimize_bit_field_compare (enum tree_code
, tree
, tree
, tree
);
105 static tree
decode_field_reference (tree
, HOST_WIDE_INT
*, HOST_WIDE_INT
*,
106 enum machine_mode
*, int *, int *,
108 static int all_ones_mask_p (tree
, int);
109 static tree
sign_bit_p (tree
, tree
);
110 static int simple_operand_p (tree
);
111 static tree
range_binop (enum tree_code
, tree
, tree
, int, tree
, int);
112 static tree
make_range (tree
, int *, tree
*, tree
*);
113 static tree
build_range_check (tree
, tree
, int, tree
, tree
);
114 static int merge_ranges (int *, tree
*, tree
*, int, tree
, tree
, int, tree
,
116 static tree
fold_range_test (enum tree_code
, tree
, tree
, tree
);
117 static tree
fold_cond_expr_with_comparison (tree
, tree
, tree
, tree
);
118 static tree
unextend (tree
, int, int, tree
);
119 static tree
fold_truthop (enum tree_code
, tree
, tree
, tree
);
120 static tree
optimize_minmax_comparison (enum tree_code
, tree
, tree
, tree
);
121 static tree
extract_muldiv (tree
, tree
, enum tree_code
, tree
);
122 static tree
extract_muldiv_1 (tree
, tree
, enum tree_code
, tree
);
123 static int multiple_of_p (tree
, tree
, tree
);
124 static tree
fold_binary_op_with_conditional_arg (enum tree_code
, tree
,
127 static bool fold_real_zero_addition_p (tree
, tree
, int);
128 static tree
fold_mathfn_compare (enum built_in_function
, enum tree_code
,
130 static tree
fold_inf_compare (enum tree_code
, tree
, tree
, tree
);
131 static tree
fold_div_compare (enum tree_code
, tree
, tree
, tree
);
132 static bool reorder_operands_p (tree
, tree
);
133 static tree
fold_negate_const (tree
, tree
);
134 static tree
fold_not_const (tree
, tree
);
135 static tree
fold_relational_const (enum tree_code
, tree
, tree
, tree
);
136 static bool tree_expr_nonzero_p (tree
);
138 /* We know that A1 + B1 = SUM1, using 2's complement arithmetic and ignoring
139 overflow. Suppose A, B and SUM have the same respective signs as A1, B1,
140 and SUM1. Then this yields nonzero if overflow occurred during the
143 Overflow occurs if A and B have the same sign, but A and SUM differ in
144 sign. Use `^' to test whether signs differ, and `< 0' to isolate the
146 #define OVERFLOW_SUM_SIGN(a, b, sum) ((~((a) ^ (b)) & ((a) ^ (sum))) < 0)
148 /* To do constant folding on INTEGER_CST nodes requires two-word arithmetic.
149 We do that by representing the two-word integer in 4 words, with only
150 HOST_BITS_PER_WIDE_INT / 2 bits stored in each word, as a positive
151 number. The value of the word is LOWPART + HIGHPART * BASE. */
154 ((x) & (((unsigned HOST_WIDE_INT) 1 << (HOST_BITS_PER_WIDE_INT / 2)) - 1))
155 #define HIGHPART(x) \
156 ((unsigned HOST_WIDE_INT) (x) >> HOST_BITS_PER_WIDE_INT / 2)
157 #define BASE ((unsigned HOST_WIDE_INT) 1 << HOST_BITS_PER_WIDE_INT / 2)
159 /* Unpack a two-word integer into 4 words.
160 LOW and HI are the integer, as two `HOST_WIDE_INT' pieces.
161 WORDS points to the array of HOST_WIDE_INTs. */
164 encode (HOST_WIDE_INT
*words
, unsigned HOST_WIDE_INT low
, HOST_WIDE_INT hi
)
166 words
[0] = LOWPART (low
);
167 words
[1] = HIGHPART (low
);
168 words
[2] = LOWPART (hi
);
169 words
[3] = HIGHPART (hi
);
172 /* Pack an array of 4 words into a two-word integer.
173 WORDS points to the array of words.
174 The integer is stored into *LOW and *HI as two `HOST_WIDE_INT' pieces. */
177 decode (HOST_WIDE_INT
*words
, unsigned HOST_WIDE_INT
*low
,
180 *low
= words
[0] + words
[1] * BASE
;
181 *hi
= words
[2] + words
[3] * BASE
;
184 /* T is an INT_CST node. OVERFLOWABLE indicates if we are interested
185 in overflow of the value, when >0 we are only interested in signed
186 overflow, for <0 we are interested in any overflow. OVERFLOWED
187 indicates whether overflow has already occurred. CONST_OVERFLOWED
188 indicates whether constant overflow has already occurred. We force
189 T's value to be within range of T's type (by setting to 0 or 1 all
190 the bits outside the type's range). We set TREE_OVERFLOWED if,
191 OVERFLOWED is nonzero,
192 or OVERFLOWABLE is >0 and signed overflow occurs
193 or OVERFLOWABLE is <0 and any overflow occurs
194 We set TREE_CONSTANT_OVERFLOWED if,
195 CONST_OVERFLOWED is nonzero
196 or we set TREE_OVERFLOWED.
197 We return either the original T, or a copy. */
200 force_fit_type (tree t
, int overflowable
,
201 bool overflowed
, bool overflowed_const
)
203 unsigned HOST_WIDE_INT low
;
206 int sign_extended_type
;
208 gcc_assert (TREE_CODE (t
) == INTEGER_CST
);
210 low
= TREE_INT_CST_LOW (t
);
211 high
= TREE_INT_CST_HIGH (t
);
213 if (POINTER_TYPE_P (TREE_TYPE (t
))
214 || TREE_CODE (TREE_TYPE (t
)) == OFFSET_TYPE
)
217 prec
= TYPE_PRECISION (TREE_TYPE (t
));
218 /* Size types *are* sign extended. */
219 sign_extended_type
= (!TYPE_UNSIGNED (TREE_TYPE (t
))
220 || (TREE_CODE (TREE_TYPE (t
)) == INTEGER_TYPE
221 && TYPE_IS_SIZETYPE (TREE_TYPE (t
))));
223 /* First clear all bits that are beyond the type's precision. */
225 if (prec
>= 2 * HOST_BITS_PER_WIDE_INT
)
227 else if (prec
> HOST_BITS_PER_WIDE_INT
)
228 high
&= ~((HOST_WIDE_INT
) (-1) << (prec
- HOST_BITS_PER_WIDE_INT
));
232 if (prec
< HOST_BITS_PER_WIDE_INT
)
233 low
&= ~((HOST_WIDE_INT
) (-1) << prec
);
236 if (!sign_extended_type
)
237 /* No sign extension */;
238 else if (prec
>= 2 * HOST_BITS_PER_WIDE_INT
)
239 /* Correct width already. */;
240 else if (prec
> HOST_BITS_PER_WIDE_INT
)
242 /* Sign extend top half? */
243 if (high
& ((unsigned HOST_WIDE_INT
)1
244 << (prec
- HOST_BITS_PER_WIDE_INT
- 1)))
245 high
|= (HOST_WIDE_INT
) (-1) << (prec
- HOST_BITS_PER_WIDE_INT
);
247 else if (prec
== HOST_BITS_PER_WIDE_INT
)
249 if ((HOST_WIDE_INT
)low
< 0)
254 /* Sign extend bottom half? */
255 if (low
& ((unsigned HOST_WIDE_INT
)1 << (prec
- 1)))
258 low
|= (HOST_WIDE_INT
)(-1) << prec
;
262 /* If the value changed, return a new node. */
263 if (overflowed
|| overflowed_const
264 || low
!= TREE_INT_CST_LOW (t
) || high
!= TREE_INT_CST_HIGH (t
))
266 t
= build_int_cst_wide (TREE_TYPE (t
), low
, high
);
270 || (overflowable
> 0 && sign_extended_type
))
273 TREE_OVERFLOW (t
) = 1;
274 TREE_CONSTANT_OVERFLOW (t
) = 1;
276 else if (overflowed_const
)
279 TREE_CONSTANT_OVERFLOW (t
) = 1;
286 /* Add two doubleword integers with doubleword result.
287 Each argument is given as two `HOST_WIDE_INT' pieces.
288 One argument is L1 and H1; the other, L2 and H2.
289 The value is stored as two `HOST_WIDE_INT' pieces in *LV and *HV. */
292 add_double (unsigned HOST_WIDE_INT l1
, HOST_WIDE_INT h1
,
293 unsigned HOST_WIDE_INT l2
, HOST_WIDE_INT h2
,
294 unsigned HOST_WIDE_INT
*lv
, HOST_WIDE_INT
*hv
)
296 unsigned HOST_WIDE_INT l
;
300 h
= h1
+ h2
+ (l
< l1
);
304 return OVERFLOW_SUM_SIGN (h1
, h2
, h
);
307 /* Negate a doubleword integer with doubleword result.
308 Return nonzero if the operation overflows, assuming it's signed.
309 The argument is given as two `HOST_WIDE_INT' pieces in L1 and H1.
310 The value is stored as two `HOST_WIDE_INT' pieces in *LV and *HV. */
313 neg_double (unsigned HOST_WIDE_INT l1
, HOST_WIDE_INT h1
,
314 unsigned HOST_WIDE_INT
*lv
, HOST_WIDE_INT
*hv
)
320 return (*hv
& h1
) < 0;
330 /* Multiply two doubleword integers with doubleword result.
331 Return nonzero if the operation overflows, assuming it's signed.
332 Each argument is given as two `HOST_WIDE_INT' pieces.
333 One argument is L1 and H1; the other, L2 and H2.
334 The value is stored as two `HOST_WIDE_INT' pieces in *LV and *HV. */
337 mul_double (unsigned HOST_WIDE_INT l1
, HOST_WIDE_INT h1
,
338 unsigned HOST_WIDE_INT l2
, HOST_WIDE_INT h2
,
339 unsigned HOST_WIDE_INT
*lv
, HOST_WIDE_INT
*hv
)
341 HOST_WIDE_INT arg1
[4];
342 HOST_WIDE_INT arg2
[4];
343 HOST_WIDE_INT prod
[4 * 2];
344 unsigned HOST_WIDE_INT carry
;
346 unsigned HOST_WIDE_INT toplow
, neglow
;
347 HOST_WIDE_INT tophigh
, neghigh
;
349 encode (arg1
, l1
, h1
);
350 encode (arg2
, l2
, h2
);
352 memset (prod
, 0, sizeof prod
);
354 for (i
= 0; i
< 4; i
++)
357 for (j
= 0; j
< 4; j
++)
360 /* This product is <= 0xFFFE0001, the sum <= 0xFFFF0000. */
361 carry
+= arg1
[i
] * arg2
[j
];
362 /* Since prod[p] < 0xFFFF, this sum <= 0xFFFFFFFF. */
364 prod
[k
] = LOWPART (carry
);
365 carry
= HIGHPART (carry
);
370 decode (prod
, lv
, hv
); /* This ignores prod[4] through prod[4*2-1] */
372 /* Check for overflow by calculating the top half of the answer in full;
373 it should agree with the low half's sign bit. */
374 decode (prod
+ 4, &toplow
, &tophigh
);
377 neg_double (l2
, h2
, &neglow
, &neghigh
);
378 add_double (neglow
, neghigh
, toplow
, tophigh
, &toplow
, &tophigh
);
382 neg_double (l1
, h1
, &neglow
, &neghigh
);
383 add_double (neglow
, neghigh
, toplow
, tophigh
, &toplow
, &tophigh
);
385 return (*hv
< 0 ? ~(toplow
& tophigh
) : toplow
| tophigh
) != 0;
388 /* Shift the doubleword integer in L1, H1 left by COUNT places
389 keeping only PREC bits of result.
390 Shift right if COUNT is negative.
391 ARITH nonzero specifies arithmetic shifting; otherwise use logical shift.
392 Store the value as two `HOST_WIDE_INT' pieces in *LV and *HV. */
395 lshift_double (unsigned HOST_WIDE_INT l1
, HOST_WIDE_INT h1
,
396 HOST_WIDE_INT count
, unsigned int prec
,
397 unsigned HOST_WIDE_INT
*lv
, HOST_WIDE_INT
*hv
, int arith
)
399 unsigned HOST_WIDE_INT signmask
;
403 rshift_double (l1
, h1
, -count
, prec
, lv
, hv
, arith
);
407 if (SHIFT_COUNT_TRUNCATED
)
410 if (count
>= 2 * HOST_BITS_PER_WIDE_INT
)
412 /* Shifting by the host word size is undefined according to the
413 ANSI standard, so we must handle this as a special case. */
417 else if (count
>= HOST_BITS_PER_WIDE_INT
)
419 *hv
= l1
<< (count
- HOST_BITS_PER_WIDE_INT
);
424 *hv
= (((unsigned HOST_WIDE_INT
) h1
<< count
)
425 | (l1
>> (HOST_BITS_PER_WIDE_INT
- count
- 1) >> 1));
429 /* Sign extend all bits that are beyond the precision. */
431 signmask
= -((prec
> HOST_BITS_PER_WIDE_INT
432 ? ((unsigned HOST_WIDE_INT
) *hv
433 >> (prec
- HOST_BITS_PER_WIDE_INT
- 1))
434 : (*lv
>> (prec
- 1))) & 1);
436 if (prec
>= 2 * HOST_BITS_PER_WIDE_INT
)
438 else if (prec
>= HOST_BITS_PER_WIDE_INT
)
440 *hv
&= ~((HOST_WIDE_INT
) (-1) << (prec
- HOST_BITS_PER_WIDE_INT
));
441 *hv
|= signmask
<< (prec
- HOST_BITS_PER_WIDE_INT
);
446 *lv
&= ~((unsigned HOST_WIDE_INT
) (-1) << prec
);
447 *lv
|= signmask
<< prec
;
451 /* Shift the doubleword integer in L1, H1 right by COUNT places
452 keeping only PREC bits of result. COUNT must be positive.
453 ARITH nonzero specifies arithmetic shifting; otherwise use logical shift.
454 Store the value as two `HOST_WIDE_INT' pieces in *LV and *HV. */
457 rshift_double (unsigned HOST_WIDE_INT l1
, HOST_WIDE_INT h1
,
458 HOST_WIDE_INT count
, unsigned int prec
,
459 unsigned HOST_WIDE_INT
*lv
, HOST_WIDE_INT
*hv
,
462 unsigned HOST_WIDE_INT signmask
;
465 ? -((unsigned HOST_WIDE_INT
) h1
>> (HOST_BITS_PER_WIDE_INT
- 1))
468 if (SHIFT_COUNT_TRUNCATED
)
471 if (count
>= 2 * HOST_BITS_PER_WIDE_INT
)
473 /* Shifting by the host word size is undefined according to the
474 ANSI standard, so we must handle this as a special case. */
478 else if (count
>= HOST_BITS_PER_WIDE_INT
)
481 *lv
= (unsigned HOST_WIDE_INT
) h1
>> (count
- HOST_BITS_PER_WIDE_INT
);
485 *hv
= (unsigned HOST_WIDE_INT
) h1
>> count
;
487 | ((unsigned HOST_WIDE_INT
) h1
<< (HOST_BITS_PER_WIDE_INT
- count
- 1) << 1));
490 /* Zero / sign extend all bits that are beyond the precision. */
492 if (count
>= (HOST_WIDE_INT
)prec
)
497 else if ((prec
- count
) >= 2 * HOST_BITS_PER_WIDE_INT
)
499 else if ((prec
- count
) >= HOST_BITS_PER_WIDE_INT
)
501 *hv
&= ~((HOST_WIDE_INT
) (-1) << (prec
- count
- HOST_BITS_PER_WIDE_INT
));
502 *hv
|= signmask
<< (prec
- count
- HOST_BITS_PER_WIDE_INT
);
507 *lv
&= ~((unsigned HOST_WIDE_INT
) (-1) << (prec
- count
));
508 *lv
|= signmask
<< (prec
- count
);
512 /* Rotate the doubleword integer in L1, H1 left by COUNT places
513 keeping only PREC bits of result.
514 Rotate right if COUNT is negative.
515 Store the value as two `HOST_WIDE_INT' pieces in *LV and *HV. */
518 lrotate_double (unsigned HOST_WIDE_INT l1
, HOST_WIDE_INT h1
,
519 HOST_WIDE_INT count
, unsigned int prec
,
520 unsigned HOST_WIDE_INT
*lv
, HOST_WIDE_INT
*hv
)
522 unsigned HOST_WIDE_INT s1l
, s2l
;
523 HOST_WIDE_INT s1h
, s2h
;
529 lshift_double (l1
, h1
, count
, prec
, &s1l
, &s1h
, 0);
530 rshift_double (l1
, h1
, prec
- count
, prec
, &s2l
, &s2h
, 0);
535 /* Rotate the doubleword integer in L1, H1 left by COUNT places
536 keeping only PREC bits of result. COUNT must be positive.
537 Store the value as two `HOST_WIDE_INT' pieces in *LV and *HV. */
540 rrotate_double (unsigned HOST_WIDE_INT l1
, HOST_WIDE_INT h1
,
541 HOST_WIDE_INT count
, unsigned int prec
,
542 unsigned HOST_WIDE_INT
*lv
, HOST_WIDE_INT
*hv
)
544 unsigned HOST_WIDE_INT s1l
, s2l
;
545 HOST_WIDE_INT s1h
, s2h
;
551 rshift_double (l1
, h1
, count
, prec
, &s1l
, &s1h
, 0);
552 lshift_double (l1
, h1
, prec
- count
, prec
, &s2l
, &s2h
, 0);
557 /* Divide doubleword integer LNUM, HNUM by doubleword integer LDEN, HDEN
558 for a quotient (stored in *LQUO, *HQUO) and remainder (in *LREM, *HREM).
559 CODE is a tree code for a kind of division, one of
560 TRUNC_DIV_EXPR, FLOOR_DIV_EXPR, CEIL_DIV_EXPR, ROUND_DIV_EXPR
562 It controls how the quotient is rounded to an integer.
563 Return nonzero if the operation overflows.
564 UNS nonzero says do unsigned division. */
567 div_and_round_double (enum tree_code code
, int uns
,
568 unsigned HOST_WIDE_INT lnum_orig
, /* num == numerator == dividend */
569 HOST_WIDE_INT hnum_orig
,
570 unsigned HOST_WIDE_INT lden_orig
, /* den == denominator == divisor */
571 HOST_WIDE_INT hden_orig
,
572 unsigned HOST_WIDE_INT
*lquo
,
573 HOST_WIDE_INT
*hquo
, unsigned HOST_WIDE_INT
*lrem
,
577 HOST_WIDE_INT num
[4 + 1]; /* extra element for scaling. */
578 HOST_WIDE_INT den
[4], quo
[4];
580 unsigned HOST_WIDE_INT work
;
581 unsigned HOST_WIDE_INT carry
= 0;
582 unsigned HOST_WIDE_INT lnum
= lnum_orig
;
583 HOST_WIDE_INT hnum
= hnum_orig
;
584 unsigned HOST_WIDE_INT lden
= lden_orig
;
585 HOST_WIDE_INT hden
= hden_orig
;
588 if (hden
== 0 && lden
== 0)
589 overflow
= 1, lden
= 1;
591 /* Calculate quotient sign and convert operands to unsigned. */
597 /* (minimum integer) / (-1) is the only overflow case. */
598 if (neg_double (lnum
, hnum
, &lnum
, &hnum
)
599 && ((HOST_WIDE_INT
) lden
& hden
) == -1)
605 neg_double (lden
, hden
, &lden
, &hden
);
609 if (hnum
== 0 && hden
== 0)
610 { /* single precision */
612 /* This unsigned division rounds toward zero. */
618 { /* trivial case: dividend < divisor */
619 /* hden != 0 already checked. */
626 memset (quo
, 0, sizeof quo
);
628 memset (num
, 0, sizeof num
); /* to zero 9th element */
629 memset (den
, 0, sizeof den
);
631 encode (num
, lnum
, hnum
);
632 encode (den
, lden
, hden
);
634 /* Special code for when the divisor < BASE. */
635 if (hden
== 0 && lden
< (unsigned HOST_WIDE_INT
) BASE
)
637 /* hnum != 0 already checked. */
638 for (i
= 4 - 1; i
>= 0; i
--)
640 work
= num
[i
] + carry
* BASE
;
641 quo
[i
] = work
/ lden
;
647 /* Full double precision division,
648 with thanks to Don Knuth's "Seminumerical Algorithms". */
649 int num_hi_sig
, den_hi_sig
;
650 unsigned HOST_WIDE_INT quo_est
, scale
;
652 /* Find the highest nonzero divisor digit. */
653 for (i
= 4 - 1;; i
--)
660 /* Insure that the first digit of the divisor is at least BASE/2.
661 This is required by the quotient digit estimation algorithm. */
663 scale
= BASE
/ (den
[den_hi_sig
] + 1);
665 { /* scale divisor and dividend */
667 for (i
= 0; i
<= 4 - 1; i
++)
669 work
= (num
[i
] * scale
) + carry
;
670 num
[i
] = LOWPART (work
);
671 carry
= HIGHPART (work
);
676 for (i
= 0; i
<= 4 - 1; i
++)
678 work
= (den
[i
] * scale
) + carry
;
679 den
[i
] = LOWPART (work
);
680 carry
= HIGHPART (work
);
681 if (den
[i
] != 0) den_hi_sig
= i
;
688 for (i
= num_hi_sig
- den_hi_sig
- 1; i
>= 0; i
--)
690 /* Guess the next quotient digit, quo_est, by dividing the first
691 two remaining dividend digits by the high order quotient digit.
692 quo_est is never low and is at most 2 high. */
693 unsigned HOST_WIDE_INT tmp
;
695 num_hi_sig
= i
+ den_hi_sig
+ 1;
696 work
= num
[num_hi_sig
] * BASE
+ num
[num_hi_sig
- 1];
697 if (num
[num_hi_sig
] != den
[den_hi_sig
])
698 quo_est
= work
/ den
[den_hi_sig
];
702 /* Refine quo_est so it's usually correct, and at most one high. */
703 tmp
= work
- quo_est
* den
[den_hi_sig
];
705 && (den
[den_hi_sig
- 1] * quo_est
706 > (tmp
* BASE
+ num
[num_hi_sig
- 2])))
709 /* Try QUO_EST as the quotient digit, by multiplying the
710 divisor by QUO_EST and subtracting from the remaining dividend.
711 Keep in mind that QUO_EST is the I - 1st digit. */
714 for (j
= 0; j
<= den_hi_sig
; j
++)
716 work
= quo_est
* den
[j
] + carry
;
717 carry
= HIGHPART (work
);
718 work
= num
[i
+ j
] - LOWPART (work
);
719 num
[i
+ j
] = LOWPART (work
);
720 carry
+= HIGHPART (work
) != 0;
723 /* If quo_est was high by one, then num[i] went negative and
724 we need to correct things. */
725 if (num
[num_hi_sig
] < (HOST_WIDE_INT
) carry
)
728 carry
= 0; /* add divisor back in */
729 for (j
= 0; j
<= den_hi_sig
; j
++)
731 work
= num
[i
+ j
] + den
[j
] + carry
;
732 carry
= HIGHPART (work
);
733 num
[i
+ j
] = LOWPART (work
);
736 num
[num_hi_sig
] += carry
;
739 /* Store the quotient digit. */
744 decode (quo
, lquo
, hquo
);
747 /* If result is negative, make it so. */
749 neg_double (*lquo
, *hquo
, lquo
, hquo
);
751 /* Compute trial remainder: rem = num - (quo * den) */
752 mul_double (*lquo
, *hquo
, lden_orig
, hden_orig
, lrem
, hrem
);
753 neg_double (*lrem
, *hrem
, lrem
, hrem
);
754 add_double (lnum_orig
, hnum_orig
, *lrem
, *hrem
, lrem
, hrem
);
759 case TRUNC_MOD_EXPR
: /* round toward zero */
760 case EXACT_DIV_EXPR
: /* for this one, it shouldn't matter */
764 case FLOOR_MOD_EXPR
: /* round toward negative infinity */
765 if (quo_neg
&& (*lrem
!= 0 || *hrem
!= 0)) /* ratio < 0 && rem != 0 */
768 add_double (*lquo
, *hquo
, (HOST_WIDE_INT
) -1, (HOST_WIDE_INT
) -1,
776 case CEIL_MOD_EXPR
: /* round toward positive infinity */
777 if (!quo_neg
&& (*lrem
!= 0 || *hrem
!= 0)) /* ratio > 0 && rem != 0 */
779 add_double (*lquo
, *hquo
, (HOST_WIDE_INT
) 1, (HOST_WIDE_INT
) 0,
787 case ROUND_MOD_EXPR
: /* round to closest integer */
789 unsigned HOST_WIDE_INT labs_rem
= *lrem
;
790 HOST_WIDE_INT habs_rem
= *hrem
;
791 unsigned HOST_WIDE_INT labs_den
= lden
, ltwice
;
792 HOST_WIDE_INT habs_den
= hden
, htwice
;
794 /* Get absolute values. */
796 neg_double (*lrem
, *hrem
, &labs_rem
, &habs_rem
);
798 neg_double (lden
, hden
, &labs_den
, &habs_den
);
800 /* If (2 * abs (lrem) >= abs (lden)) */
801 mul_double ((HOST_WIDE_INT
) 2, (HOST_WIDE_INT
) 0,
802 labs_rem
, habs_rem
, <wice
, &htwice
);
804 if (((unsigned HOST_WIDE_INT
) habs_den
805 < (unsigned HOST_WIDE_INT
) htwice
)
806 || (((unsigned HOST_WIDE_INT
) habs_den
807 == (unsigned HOST_WIDE_INT
) htwice
)
808 && (labs_den
< ltwice
)))
812 add_double (*lquo
, *hquo
,
813 (HOST_WIDE_INT
) -1, (HOST_WIDE_INT
) -1, lquo
, hquo
);
816 add_double (*lquo
, *hquo
, (HOST_WIDE_INT
) 1, (HOST_WIDE_INT
) 0,
828 /* Compute true remainder: rem = num - (quo * den) */
829 mul_double (*lquo
, *hquo
, lden_orig
, hden_orig
, lrem
, hrem
);
830 neg_double (*lrem
, *hrem
, lrem
, hrem
);
831 add_double (lnum_orig
, hnum_orig
, *lrem
, *hrem
, lrem
, hrem
);
835 /* Return true if built-in mathematical function specified by CODE
836 preserves the sign of it argument, i.e. -f(x) == f(-x). */
839 negate_mathfn_p (enum built_in_function code
)
863 /* Check whether we may negate an integer constant T without causing
867 may_negate_without_overflow_p (tree t
)
869 unsigned HOST_WIDE_INT val
;
873 gcc_assert (TREE_CODE (t
) == INTEGER_CST
);
875 type
= TREE_TYPE (t
);
876 if (TYPE_UNSIGNED (type
))
879 prec
= TYPE_PRECISION (type
);
880 if (prec
> HOST_BITS_PER_WIDE_INT
)
882 if (TREE_INT_CST_LOW (t
) != 0)
884 prec
-= HOST_BITS_PER_WIDE_INT
;
885 val
= TREE_INT_CST_HIGH (t
);
888 val
= TREE_INT_CST_LOW (t
);
889 if (prec
< HOST_BITS_PER_WIDE_INT
)
890 val
&= ((unsigned HOST_WIDE_INT
) 1 << prec
) - 1;
891 return val
!= ((unsigned HOST_WIDE_INT
) 1 << (prec
- 1));
894 /* Determine whether an expression T can be cheaply negated using
895 the function negate_expr. */
898 negate_expr_p (tree t
)
905 type
= TREE_TYPE (t
);
908 switch (TREE_CODE (t
))
911 if (TYPE_UNSIGNED (type
) || ! flag_trapv
)
914 /* Check that -CST will not overflow type. */
915 return may_negate_without_overflow_p (t
);
922 return negate_expr_p (TREE_REALPART (t
))
923 && negate_expr_p (TREE_IMAGPART (t
));
926 if (FLOAT_TYPE_P (type
) && !flag_unsafe_math_optimizations
)
928 /* -(A + B) -> (-B) - A. */
929 if (negate_expr_p (TREE_OPERAND (t
, 1))
930 && reorder_operands_p (TREE_OPERAND (t
, 0),
931 TREE_OPERAND (t
, 1)))
933 /* -(A + B) -> (-A) - B. */
934 return negate_expr_p (TREE_OPERAND (t
, 0));
937 /* We can't turn -(A-B) into B-A when we honor signed zeros. */
938 return (! FLOAT_TYPE_P (type
) || flag_unsafe_math_optimizations
)
939 && reorder_operands_p (TREE_OPERAND (t
, 0),
940 TREE_OPERAND (t
, 1));
943 if (TYPE_UNSIGNED (TREE_TYPE (t
)))
949 if (! HONOR_SIGN_DEPENDENT_ROUNDING (TYPE_MODE (TREE_TYPE (t
))))
950 return negate_expr_p (TREE_OPERAND (t
, 1))
951 || negate_expr_p (TREE_OPERAND (t
, 0));
955 /* Negate -((double)float) as (double)(-float). */
956 if (TREE_CODE (type
) == REAL_TYPE
)
958 tree tem
= strip_float_extensions (t
);
960 return negate_expr_p (tem
);
965 /* Negate -f(x) as f(-x). */
966 if (negate_mathfn_p (builtin_mathfn_code (t
)))
967 return negate_expr_p (TREE_VALUE (TREE_OPERAND (t
, 1)));
971 /* Optimize -((int)x >> 31) into (unsigned)x >> 31. */
972 if (TREE_CODE (TREE_OPERAND (t
, 1)) == INTEGER_CST
)
974 tree op1
= TREE_OPERAND (t
, 1);
975 if (TREE_INT_CST_HIGH (op1
) == 0
976 && (unsigned HOST_WIDE_INT
) (TYPE_PRECISION (type
) - 1)
977 == TREE_INT_CST_LOW (op1
))
988 /* Given T, an expression, return the negation of T. Allow for T to be
989 null, in which case return null. */
1000 type
= TREE_TYPE (t
);
1001 STRIP_SIGN_NOPS (t
);
1003 switch (TREE_CODE (t
))
1006 tem
= fold_negate_const (t
, type
);
1007 if (! TREE_OVERFLOW (tem
)
1008 || TYPE_UNSIGNED (type
)
1014 tem
= fold_negate_const (t
, type
);
1015 /* Two's complement FP formats, such as c4x, may overflow. */
1016 if (! TREE_OVERFLOW (tem
) || ! flag_trapping_math
)
1017 return fold_convert (type
, tem
);
1022 tree rpart
= negate_expr (TREE_REALPART (t
));
1023 tree ipart
= negate_expr (TREE_IMAGPART (t
));
1025 if ((TREE_CODE (rpart
) == REAL_CST
1026 && TREE_CODE (ipart
) == REAL_CST
)
1027 || (TREE_CODE (rpart
) == INTEGER_CST
1028 && TREE_CODE (ipart
) == INTEGER_CST
))
1029 return build_complex (type
, rpart
, ipart
);
1034 return fold_convert (type
, TREE_OPERAND (t
, 0));
1037 if (! FLOAT_TYPE_P (type
) || flag_unsafe_math_optimizations
)
1039 /* -(A + B) -> (-B) - A. */
1040 if (negate_expr_p (TREE_OPERAND (t
, 1))
1041 && reorder_operands_p (TREE_OPERAND (t
, 0),
1042 TREE_OPERAND (t
, 1)))
1044 tem
= negate_expr (TREE_OPERAND (t
, 1));
1045 tem
= fold_build2 (MINUS_EXPR
, TREE_TYPE (t
),
1046 tem
, TREE_OPERAND (t
, 0));
1047 return fold_convert (type
, tem
);
1050 /* -(A + B) -> (-A) - B. */
1051 if (negate_expr_p (TREE_OPERAND (t
, 0)))
1053 tem
= negate_expr (TREE_OPERAND (t
, 0));
1054 tem
= fold_build2 (MINUS_EXPR
, TREE_TYPE (t
),
1055 tem
, TREE_OPERAND (t
, 1));
1056 return fold_convert (type
, tem
);
1062 /* - (A - B) -> B - A */
1063 if ((! FLOAT_TYPE_P (type
) || flag_unsafe_math_optimizations
)
1064 && reorder_operands_p (TREE_OPERAND (t
, 0), TREE_OPERAND (t
, 1)))
1065 return fold_convert (type
,
1066 fold_build2 (MINUS_EXPR
, TREE_TYPE (t
),
1067 TREE_OPERAND (t
, 1),
1068 TREE_OPERAND (t
, 0)));
1072 if (TYPE_UNSIGNED (TREE_TYPE (t
)))
1078 if (! HONOR_SIGN_DEPENDENT_ROUNDING (TYPE_MODE (TREE_TYPE (t
))))
1080 tem
= TREE_OPERAND (t
, 1);
1081 if (negate_expr_p (tem
))
1082 return fold_convert (type
,
1083 fold_build2 (TREE_CODE (t
), TREE_TYPE (t
),
1084 TREE_OPERAND (t
, 0),
1085 negate_expr (tem
)));
1086 tem
= TREE_OPERAND (t
, 0);
1087 if (negate_expr_p (tem
))
1088 return fold_convert (type
,
1089 fold_build2 (TREE_CODE (t
), TREE_TYPE (t
),
1091 TREE_OPERAND (t
, 1)));
1096 /* Convert -((double)float) into (double)(-float). */
1097 if (TREE_CODE (type
) == REAL_TYPE
)
1099 tem
= strip_float_extensions (t
);
1100 if (tem
!= t
&& negate_expr_p (tem
))
1101 return fold_convert (type
, negate_expr (tem
));
1106 /* Negate -f(x) as f(-x). */
1107 if (negate_mathfn_p (builtin_mathfn_code (t
))
1108 && negate_expr_p (TREE_VALUE (TREE_OPERAND (t
, 1))))
1110 tree fndecl
, arg
, arglist
;
1112 fndecl
= get_callee_fndecl (t
);
1113 arg
= negate_expr (TREE_VALUE (TREE_OPERAND (t
, 1)));
1114 arglist
= build_tree_list (NULL_TREE
, arg
);
1115 return build_function_call_expr (fndecl
, arglist
);
1120 /* Optimize -((int)x >> 31) into (unsigned)x >> 31. */
1121 if (TREE_CODE (TREE_OPERAND (t
, 1)) == INTEGER_CST
)
1123 tree op1
= TREE_OPERAND (t
, 1);
1124 if (TREE_INT_CST_HIGH (op1
) == 0
1125 && (unsigned HOST_WIDE_INT
) (TYPE_PRECISION (type
) - 1)
1126 == TREE_INT_CST_LOW (op1
))
1128 tree ntype
= TYPE_UNSIGNED (type
)
1129 ? lang_hooks
.types
.signed_type (type
)
1130 : lang_hooks
.types
.unsigned_type (type
);
1131 tree temp
= fold_convert (ntype
, TREE_OPERAND (t
, 0));
1132 temp
= fold_build2 (RSHIFT_EXPR
, ntype
, temp
, op1
);
1133 return fold_convert (type
, temp
);
1142 tem
= fold_build1 (NEGATE_EXPR
, TREE_TYPE (t
), t
);
1143 return fold_convert (type
, tem
);
1146 /* Split a tree IN into a constant, literal and variable parts that could be
1147 combined with CODE to make IN. "constant" means an expression with
1148 TREE_CONSTANT but that isn't an actual constant. CODE must be a
1149 commutative arithmetic operation. Store the constant part into *CONP,
1150 the literal in *LITP and return the variable part. If a part isn't
1151 present, set it to null. If the tree does not decompose in this way,
1152 return the entire tree as the variable part and the other parts as null.
1154 If CODE is PLUS_EXPR we also split trees that use MINUS_EXPR. In that
1155 case, we negate an operand that was subtracted. Except if it is a
1156 literal for which we use *MINUS_LITP instead.
1158 If NEGATE_P is true, we are negating all of IN, again except a literal
1159 for which we use *MINUS_LITP instead.
1161 If IN is itself a literal or constant, return it as appropriate.
1163 Note that we do not guarantee that any of the three values will be the
1164 same type as IN, but they will have the same signedness and mode. */
1167 split_tree (tree in
, enum tree_code code
, tree
*conp
, tree
*litp
,
1168 tree
*minus_litp
, int negate_p
)
1176 /* Strip any conversions that don't change the machine mode or signedness. */
1177 STRIP_SIGN_NOPS (in
);
1179 if (TREE_CODE (in
) == INTEGER_CST
|| TREE_CODE (in
) == REAL_CST
)
1181 else if (TREE_CODE (in
) == code
1182 || (! FLOAT_TYPE_P (TREE_TYPE (in
))
1183 /* We can associate addition and subtraction together (even
1184 though the C standard doesn't say so) for integers because
1185 the value is not affected. For reals, the value might be
1186 affected, so we can't. */
1187 && ((code
== PLUS_EXPR
&& TREE_CODE (in
) == MINUS_EXPR
)
1188 || (code
== MINUS_EXPR
&& TREE_CODE (in
) == PLUS_EXPR
))))
1190 tree op0
= TREE_OPERAND (in
, 0);
1191 tree op1
= TREE_OPERAND (in
, 1);
1192 int neg1_p
= TREE_CODE (in
) == MINUS_EXPR
;
1193 int neg_litp_p
= 0, neg_conp_p
= 0, neg_var_p
= 0;
1195 /* First see if either of the operands is a literal, then a constant. */
1196 if (TREE_CODE (op0
) == INTEGER_CST
|| TREE_CODE (op0
) == REAL_CST
)
1197 *litp
= op0
, op0
= 0;
1198 else if (TREE_CODE (op1
) == INTEGER_CST
|| TREE_CODE (op1
) == REAL_CST
)
1199 *litp
= op1
, neg_litp_p
= neg1_p
, op1
= 0;
1201 if (op0
!= 0 && TREE_CONSTANT (op0
))
1202 *conp
= op0
, op0
= 0;
1203 else if (op1
!= 0 && TREE_CONSTANT (op1
))
1204 *conp
= op1
, neg_conp_p
= neg1_p
, op1
= 0;
1206 /* If we haven't dealt with either operand, this is not a case we can
1207 decompose. Otherwise, VAR is either of the ones remaining, if any. */
1208 if (op0
!= 0 && op1
!= 0)
1213 var
= op1
, neg_var_p
= neg1_p
;
1215 /* Now do any needed negations. */
1217 *minus_litp
= *litp
, *litp
= 0;
1219 *conp
= negate_expr (*conp
);
1221 var
= negate_expr (var
);
1223 else if (TREE_CONSTANT (in
))
1231 *minus_litp
= *litp
, *litp
= 0;
1232 else if (*minus_litp
)
1233 *litp
= *minus_litp
, *minus_litp
= 0;
1234 *conp
= negate_expr (*conp
);
1235 var
= negate_expr (var
);
1241 /* Re-associate trees split by the above function. T1 and T2 are either
1242 expressions to associate or null. Return the new expression, if any. If
1243 we build an operation, do it in TYPE and with CODE. */
1246 associate_trees (tree t1
, tree t2
, enum tree_code code
, tree type
)
1253 /* If either input is CODE, a PLUS_EXPR, or a MINUS_EXPR, don't
1254 try to fold this since we will have infinite recursion. But do
1255 deal with any NEGATE_EXPRs. */
1256 if (TREE_CODE (t1
) == code
|| TREE_CODE (t2
) == code
1257 || TREE_CODE (t1
) == MINUS_EXPR
|| TREE_CODE (t2
) == MINUS_EXPR
)
1259 if (code
== PLUS_EXPR
)
1261 if (TREE_CODE (t1
) == NEGATE_EXPR
)
1262 return build2 (MINUS_EXPR
, type
, fold_convert (type
, t2
),
1263 fold_convert (type
, TREE_OPERAND (t1
, 0)));
1264 else if (TREE_CODE (t2
) == NEGATE_EXPR
)
1265 return build2 (MINUS_EXPR
, type
, fold_convert (type
, t1
),
1266 fold_convert (type
, TREE_OPERAND (t2
, 0)));
1267 else if (integer_zerop (t2
))
1268 return fold_convert (type
, t1
);
1270 else if (code
== MINUS_EXPR
)
1272 if (integer_zerop (t2
))
1273 return fold_convert (type
, t1
);
1276 return build2 (code
, type
, fold_convert (type
, t1
),
1277 fold_convert (type
, t2
));
1280 return fold_build2 (code
, type
, fold_convert (type
, t1
),
1281 fold_convert (type
, t2
));
1284 /* Combine two integer constants ARG1 and ARG2 under operation CODE
1285 to produce a new constant.
1287 If NOTRUNC is nonzero, do not truncate the result to fit the data type. */
1290 int_const_binop (enum tree_code code
, tree arg1
, tree arg2
, int notrunc
)
1292 unsigned HOST_WIDE_INT int1l
, int2l
;
1293 HOST_WIDE_INT int1h
, int2h
;
1294 unsigned HOST_WIDE_INT low
;
1296 unsigned HOST_WIDE_INT garbagel
;
1297 HOST_WIDE_INT garbageh
;
1299 tree type
= TREE_TYPE (arg1
);
1300 int uns
= TYPE_UNSIGNED (type
);
1302 = (TREE_CODE (type
) == INTEGER_TYPE
&& TYPE_IS_SIZETYPE (type
));
1305 int1l
= TREE_INT_CST_LOW (arg1
);
1306 int1h
= TREE_INT_CST_HIGH (arg1
);
1307 int2l
= TREE_INT_CST_LOW (arg2
);
1308 int2h
= TREE_INT_CST_HIGH (arg2
);
1313 low
= int1l
| int2l
, hi
= int1h
| int2h
;
1317 low
= int1l
^ int2l
, hi
= int1h
^ int2h
;
1321 low
= int1l
& int2l
, hi
= int1h
& int2h
;
1327 /* It's unclear from the C standard whether shifts can overflow.
1328 The following code ignores overflow; perhaps a C standard
1329 interpretation ruling is needed. */
1330 lshift_double (int1l
, int1h
, int2l
, TYPE_PRECISION (type
),
1337 lrotate_double (int1l
, int1h
, int2l
, TYPE_PRECISION (type
),
1342 overflow
= add_double (int1l
, int1h
, int2l
, int2h
, &low
, &hi
);
1346 neg_double (int2l
, int2h
, &low
, &hi
);
1347 add_double (int1l
, int1h
, low
, hi
, &low
, &hi
);
1348 overflow
= OVERFLOW_SUM_SIGN (hi
, int2h
, int1h
);
1352 overflow
= mul_double (int1l
, int1h
, int2l
, int2h
, &low
, &hi
);
1355 case TRUNC_DIV_EXPR
:
1356 case FLOOR_DIV_EXPR
: case CEIL_DIV_EXPR
:
1357 case EXACT_DIV_EXPR
:
1358 /* This is a shortcut for a common special case. */
1359 if (int2h
== 0 && (HOST_WIDE_INT
) int2l
> 0
1360 && ! TREE_CONSTANT_OVERFLOW (arg1
)
1361 && ! TREE_CONSTANT_OVERFLOW (arg2
)
1362 && int1h
== 0 && (HOST_WIDE_INT
) int1l
>= 0)
1364 if (code
== CEIL_DIV_EXPR
)
1367 low
= int1l
/ int2l
, hi
= 0;
1371 /* ... fall through ... */
1373 case ROUND_DIV_EXPR
:
1374 if (int2h
== 0 && int2l
== 1)
1376 low
= int1l
, hi
= int1h
;
1379 if (int1l
== int2l
&& int1h
== int2h
1380 && ! (int1l
== 0 && int1h
== 0))
1385 overflow
= div_and_round_double (code
, uns
, int1l
, int1h
, int2l
, int2h
,
1386 &low
, &hi
, &garbagel
, &garbageh
);
1389 case TRUNC_MOD_EXPR
:
1390 case FLOOR_MOD_EXPR
: case CEIL_MOD_EXPR
:
1391 /* This is a shortcut for a common special case. */
1392 if (int2h
== 0 && (HOST_WIDE_INT
) int2l
> 0
1393 && ! TREE_CONSTANT_OVERFLOW (arg1
)
1394 && ! TREE_CONSTANT_OVERFLOW (arg2
)
1395 && int1h
== 0 && (HOST_WIDE_INT
) int1l
>= 0)
1397 if (code
== CEIL_MOD_EXPR
)
1399 low
= int1l
% int2l
, hi
= 0;
1403 /* ... fall through ... */
1405 case ROUND_MOD_EXPR
:
1406 overflow
= div_and_round_double (code
, uns
,
1407 int1l
, int1h
, int2l
, int2h
,
1408 &garbagel
, &garbageh
, &low
, &hi
);
1414 low
= (((unsigned HOST_WIDE_INT
) int1h
1415 < (unsigned HOST_WIDE_INT
) int2h
)
1416 || (((unsigned HOST_WIDE_INT
) int1h
1417 == (unsigned HOST_WIDE_INT
) int2h
)
1420 low
= (int1h
< int2h
1421 || (int1h
== int2h
&& int1l
< int2l
));
1423 if (low
== (code
== MIN_EXPR
))
1424 low
= int1l
, hi
= int1h
;
1426 low
= int2l
, hi
= int2h
;
1433 t
= build_int_cst_wide (TREE_TYPE (arg1
), low
, hi
);
1437 /* Propagate overflow flags ourselves. */
1438 if (((!uns
|| is_sizetype
) && overflow
)
1439 | TREE_OVERFLOW (arg1
) | TREE_OVERFLOW (arg2
))
1442 TREE_OVERFLOW (t
) = 1;
1443 TREE_CONSTANT_OVERFLOW (t
) = 1;
1445 else if (TREE_CONSTANT_OVERFLOW (arg1
) | TREE_CONSTANT_OVERFLOW (arg2
))
1448 TREE_CONSTANT_OVERFLOW (t
) = 1;
1452 t
= force_fit_type (t
, 1,
1453 ((!uns
|| is_sizetype
) && overflow
)
1454 | TREE_OVERFLOW (arg1
) | TREE_OVERFLOW (arg2
),
1455 TREE_CONSTANT_OVERFLOW (arg1
)
1456 | TREE_CONSTANT_OVERFLOW (arg2
));
1461 /* Combine two constants ARG1 and ARG2 under operation CODE to produce a new
1462 constant. We assume ARG1 and ARG2 have the same data type, or at least
1463 are the same kind of constant and the same machine mode.
1465 If NOTRUNC is nonzero, do not truncate the result to fit the data type. */
1468 const_binop (enum tree_code code
, tree arg1
, tree arg2
, int notrunc
)
1473 if (TREE_CODE (arg1
) == INTEGER_CST
)
1474 return int_const_binop (code
, arg1
, arg2
, notrunc
);
1476 if (TREE_CODE (arg1
) == REAL_CST
)
1478 enum machine_mode mode
;
1481 REAL_VALUE_TYPE value
;
1482 REAL_VALUE_TYPE result
;
1486 d1
= TREE_REAL_CST (arg1
);
1487 d2
= TREE_REAL_CST (arg2
);
1489 type
= TREE_TYPE (arg1
);
1490 mode
= TYPE_MODE (type
);
1492 /* Don't perform operation if we honor signaling NaNs and
1493 either operand is a NaN. */
1494 if (HONOR_SNANS (mode
)
1495 && (REAL_VALUE_ISNAN (d1
) || REAL_VALUE_ISNAN (d2
)))
1498 /* Don't perform operation if it would raise a division
1499 by zero exception. */
1500 if (code
== RDIV_EXPR
1501 && REAL_VALUES_EQUAL (d2
, dconst0
)
1502 && (flag_trapping_math
|| ! MODE_HAS_INFINITIES (mode
)))
1505 /* If either operand is a NaN, just return it. Otherwise, set up
1506 for floating-point trap; we return an overflow. */
1507 if (REAL_VALUE_ISNAN (d1
))
1509 else if (REAL_VALUE_ISNAN (d2
))
1512 inexact
= real_arithmetic (&value
, code
, &d1
, &d2
);
1513 real_convert (&result
, mode
, &value
);
1515 /* Don't constant fold this floating point operation if the
1516 result may dependent upon the run-time rounding mode and
1517 flag_rounding_math is set, or if GCC's software emulation
1518 is unable to accurately represent the result. */
1520 if ((flag_rounding_math
1521 || (REAL_MODE_FORMAT_COMPOSITE_P (mode
)
1522 && !flag_unsafe_math_optimizations
))
1523 && (inexact
|| !real_identical (&result
, &value
)))
1526 t
= build_real (type
, result
);
1528 TREE_OVERFLOW (t
) = TREE_OVERFLOW (arg1
) | TREE_OVERFLOW (arg2
);
1529 TREE_CONSTANT_OVERFLOW (t
)
1531 | TREE_CONSTANT_OVERFLOW (arg1
)
1532 | TREE_CONSTANT_OVERFLOW (arg2
);
1535 if (TREE_CODE (arg1
) == COMPLEX_CST
)
1537 tree type
= TREE_TYPE (arg1
);
1538 tree r1
= TREE_REALPART (arg1
);
1539 tree i1
= TREE_IMAGPART (arg1
);
1540 tree r2
= TREE_REALPART (arg2
);
1541 tree i2
= TREE_IMAGPART (arg2
);
1547 t
= build_complex (type
,
1548 const_binop (PLUS_EXPR
, r1
, r2
, notrunc
),
1549 const_binop (PLUS_EXPR
, i1
, i2
, notrunc
));
1553 t
= build_complex (type
,
1554 const_binop (MINUS_EXPR
, r1
, r2
, notrunc
),
1555 const_binop (MINUS_EXPR
, i1
, i2
, notrunc
));
1559 t
= build_complex (type
,
1560 const_binop (MINUS_EXPR
,
1561 const_binop (MULT_EXPR
,
1563 const_binop (MULT_EXPR
,
1566 const_binop (PLUS_EXPR
,
1567 const_binop (MULT_EXPR
,
1569 const_binop (MULT_EXPR
,
1577 = const_binop (PLUS_EXPR
,
1578 const_binop (MULT_EXPR
, r2
, r2
, notrunc
),
1579 const_binop (MULT_EXPR
, i2
, i2
, notrunc
),
1582 t
= build_complex (type
,
1584 (INTEGRAL_TYPE_P (TREE_TYPE (r1
))
1585 ? TRUNC_DIV_EXPR
: RDIV_EXPR
,
1586 const_binop (PLUS_EXPR
,
1587 const_binop (MULT_EXPR
, r1
, r2
,
1589 const_binop (MULT_EXPR
, i1
, i2
,
1592 magsquared
, notrunc
),
1594 (INTEGRAL_TYPE_P (TREE_TYPE (r1
))
1595 ? TRUNC_DIV_EXPR
: RDIV_EXPR
,
1596 const_binop (MINUS_EXPR
,
1597 const_binop (MULT_EXPR
, i1
, r2
,
1599 const_binop (MULT_EXPR
, r1
, i2
,
1602 magsquared
, notrunc
));
1614 /* Create a size type INT_CST node with NUMBER sign extended. KIND
1615 indicates which particular sizetype to create. */
1618 size_int_kind (HOST_WIDE_INT number
, enum size_type_kind kind
)
1620 return build_int_cst (sizetype_tab
[(int) kind
], number
);
1623 /* Combine operands OP1 and OP2 with arithmetic operation CODE. CODE
1624 is a tree code. The type of the result is taken from the operands.
1625 Both must be the same type integer type and it must be a size type.
1626 If the operands are constant, so is the result. */
1629 size_binop (enum tree_code code
, tree arg0
, tree arg1
)
1631 tree type
= TREE_TYPE (arg0
);
1633 gcc_assert (TREE_CODE (type
) == INTEGER_TYPE
&& TYPE_IS_SIZETYPE (type
)
1634 && type
== TREE_TYPE (arg1
));
1636 /* Handle the special case of two integer constants faster. */
1637 if (TREE_CODE (arg0
) == INTEGER_CST
&& TREE_CODE (arg1
) == INTEGER_CST
)
1639 /* And some specific cases even faster than that. */
1640 if (code
== PLUS_EXPR
&& integer_zerop (arg0
))
1642 else if ((code
== MINUS_EXPR
|| code
== PLUS_EXPR
)
1643 && integer_zerop (arg1
))
1645 else if (code
== MULT_EXPR
&& integer_onep (arg0
))
1648 /* Handle general case of two integer constants. */
1649 return int_const_binop (code
, arg0
, arg1
, 0);
1652 if (arg0
== error_mark_node
|| arg1
== error_mark_node
)
1653 return error_mark_node
;
1655 return fold_build2 (code
, type
, arg0
, arg1
);
1658 /* Given two values, either both of sizetype or both of bitsizetype,
1659 compute the difference between the two values. Return the value
1660 in signed type corresponding to the type of the operands. */
1663 size_diffop (tree arg0
, tree arg1
)
1665 tree type
= TREE_TYPE (arg0
);
1668 gcc_assert (TREE_CODE (type
) == INTEGER_TYPE
&& TYPE_IS_SIZETYPE (type
)
1669 && type
== TREE_TYPE (arg1
));
1671 /* If the type is already signed, just do the simple thing. */
1672 if (!TYPE_UNSIGNED (type
))
1673 return size_binop (MINUS_EXPR
, arg0
, arg1
);
1675 ctype
= type
== bitsizetype
? sbitsizetype
: ssizetype
;
1677 /* If either operand is not a constant, do the conversions to the signed
1678 type and subtract. The hardware will do the right thing with any
1679 overflow in the subtraction. */
1680 if (TREE_CODE (arg0
) != INTEGER_CST
|| TREE_CODE (arg1
) != INTEGER_CST
)
1681 return size_binop (MINUS_EXPR
, fold_convert (ctype
, arg0
),
1682 fold_convert (ctype
, arg1
));
1684 /* If ARG0 is larger than ARG1, subtract and return the result in CTYPE.
1685 Otherwise, subtract the other way, convert to CTYPE (we know that can't
1686 overflow) and negate (which can't either). Special-case a result
1687 of zero while we're here. */
1688 if (tree_int_cst_equal (arg0
, arg1
))
1689 return fold_convert (ctype
, integer_zero_node
);
1690 else if (tree_int_cst_lt (arg1
, arg0
))
1691 return fold_convert (ctype
, size_binop (MINUS_EXPR
, arg0
, arg1
));
1693 return size_binop (MINUS_EXPR
, fold_convert (ctype
, integer_zero_node
),
1694 fold_convert (ctype
, size_binop (MINUS_EXPR
,
1698 /* A subroutine of fold_convert_const handling conversions of an
1699 INTEGER_CST to another integer type. */
1702 fold_convert_const_int_from_int (tree type
, tree arg1
)
1706 /* Given an integer constant, make new constant with new type,
1707 appropriately sign-extended or truncated. */
1708 t
= build_int_cst_wide (type
, TREE_INT_CST_LOW (arg1
),
1709 TREE_INT_CST_HIGH (arg1
));
1711 t
= force_fit_type (t
,
1712 /* Don't set the overflow when
1713 converting a pointer */
1714 !POINTER_TYPE_P (TREE_TYPE (arg1
)),
1715 (TREE_INT_CST_HIGH (arg1
) < 0
1716 && (TYPE_UNSIGNED (type
)
1717 < TYPE_UNSIGNED (TREE_TYPE (arg1
))))
1718 | TREE_OVERFLOW (arg1
),
1719 TREE_CONSTANT_OVERFLOW (arg1
));
1724 /* A subroutine of fold_convert_const handling conversions a REAL_CST
1725 to an integer type. */
1728 fold_convert_const_int_from_real (enum tree_code code
, tree type
, tree arg1
)
1733 /* The following code implements the floating point to integer
1734 conversion rules required by the Java Language Specification,
1735 that IEEE NaNs are mapped to zero and values that overflow
1736 the target precision saturate, i.e. values greater than
1737 INT_MAX are mapped to INT_MAX, and values less than INT_MIN
1738 are mapped to INT_MIN. These semantics are allowed by the
1739 C and C++ standards that simply state that the behavior of
1740 FP-to-integer conversion is unspecified upon overflow. */
1742 HOST_WIDE_INT high
, low
;
1744 REAL_VALUE_TYPE x
= TREE_REAL_CST (arg1
);
1748 case FIX_TRUNC_EXPR
:
1749 real_trunc (&r
, VOIDmode
, &x
);
1753 real_ceil (&r
, VOIDmode
, &x
);
1756 case FIX_FLOOR_EXPR
:
1757 real_floor (&r
, VOIDmode
, &x
);
1760 case FIX_ROUND_EXPR
:
1761 real_round (&r
, VOIDmode
, &x
);
1768 /* If R is NaN, return zero and show we have an overflow. */
1769 if (REAL_VALUE_ISNAN (r
))
1776 /* See if R is less than the lower bound or greater than the
1781 tree lt
= TYPE_MIN_VALUE (type
);
1782 REAL_VALUE_TYPE l
= real_value_from_int_cst (NULL_TREE
, lt
);
1783 if (REAL_VALUES_LESS (r
, l
))
1786 high
= TREE_INT_CST_HIGH (lt
);
1787 low
= TREE_INT_CST_LOW (lt
);
1793 tree ut
= TYPE_MAX_VALUE (type
);
1796 REAL_VALUE_TYPE u
= real_value_from_int_cst (NULL_TREE
, ut
);
1797 if (REAL_VALUES_LESS (u
, r
))
1800 high
= TREE_INT_CST_HIGH (ut
);
1801 low
= TREE_INT_CST_LOW (ut
);
1807 REAL_VALUE_TO_INT (&low
, &high
, r
);
1809 t
= build_int_cst_wide (type
, low
, high
);
1811 t
= force_fit_type (t
, -1, overflow
| TREE_OVERFLOW (arg1
),
1812 TREE_CONSTANT_OVERFLOW (arg1
));
1816 /* A subroutine of fold_convert_const handling conversions a REAL_CST
1817 to another floating point type. */
1820 fold_convert_const_real_from_real (tree type
, tree arg1
)
1822 REAL_VALUE_TYPE value
;
1825 real_convert (&value
, TYPE_MODE (type
), &TREE_REAL_CST (arg1
));
1826 t
= build_real (type
, value
);
1828 TREE_OVERFLOW (t
) = TREE_OVERFLOW (arg1
);
1829 TREE_CONSTANT_OVERFLOW (t
)
1830 = TREE_OVERFLOW (t
) | TREE_CONSTANT_OVERFLOW (arg1
);
1834 /* Attempt to fold type conversion operation CODE of expression ARG1 to
1835 type TYPE. If no simplification can be done return NULL_TREE. */
1838 fold_convert_const (enum tree_code code
, tree type
, tree arg1
)
1840 if (TREE_TYPE (arg1
) == type
)
1843 if (POINTER_TYPE_P (type
) || INTEGRAL_TYPE_P (type
))
1845 if (TREE_CODE (arg1
) == INTEGER_CST
)
1846 return fold_convert_const_int_from_int (type
, arg1
);
1847 else if (TREE_CODE (arg1
) == REAL_CST
)
1848 return fold_convert_const_int_from_real (code
, type
, arg1
);
1850 else if (TREE_CODE (type
) == REAL_TYPE
)
1852 if (TREE_CODE (arg1
) == INTEGER_CST
)
1853 return build_real_from_int_cst (type
, arg1
);
1854 if (TREE_CODE (arg1
) == REAL_CST
)
1855 return fold_convert_const_real_from_real (type
, arg1
);
1860 /* Construct a vector of zero elements of vector type TYPE. */
1863 build_zero_vector (tree type
)
1868 elem
= fold_convert_const (NOP_EXPR
, TREE_TYPE (type
), integer_zero_node
);
1869 units
= TYPE_VECTOR_SUBPARTS (type
);
1872 for (i
= 0; i
< units
; i
++)
1873 list
= tree_cons (NULL_TREE
, elem
, list
);
1874 return build_vector (type
, list
);
1877 /* Convert expression ARG to type TYPE. Used by the middle-end for
1878 simple conversions in preference to calling the front-end's convert. */
1881 fold_convert (tree type
, tree arg
)
1883 tree orig
= TREE_TYPE (arg
);
1889 if (TREE_CODE (arg
) == ERROR_MARK
1890 || TREE_CODE (type
) == ERROR_MARK
1891 || TREE_CODE (orig
) == ERROR_MARK
)
1892 return error_mark_node
;
1894 if (TYPE_MAIN_VARIANT (type
) == TYPE_MAIN_VARIANT (orig
)
1895 || lang_hooks
.types_compatible_p (TYPE_MAIN_VARIANT (type
),
1896 TYPE_MAIN_VARIANT (orig
)))
1897 return fold_build1 (NOP_EXPR
, type
, arg
);
1899 switch (TREE_CODE (type
))
1901 case INTEGER_TYPE
: case CHAR_TYPE
: case ENUMERAL_TYPE
: case BOOLEAN_TYPE
:
1902 case POINTER_TYPE
: case REFERENCE_TYPE
:
1904 if (TREE_CODE (arg
) == INTEGER_CST
)
1906 tem
= fold_convert_const (NOP_EXPR
, type
, arg
);
1907 if (tem
!= NULL_TREE
)
1910 if (INTEGRAL_TYPE_P (orig
) || POINTER_TYPE_P (orig
)
1911 || TREE_CODE (orig
) == OFFSET_TYPE
)
1912 return fold_build1 (NOP_EXPR
, type
, arg
);
1913 if (TREE_CODE (orig
) == COMPLEX_TYPE
)
1915 tem
= fold_build1 (REALPART_EXPR
, TREE_TYPE (orig
), arg
);
1916 return fold_convert (type
, tem
);
1918 gcc_assert (TREE_CODE (orig
) == VECTOR_TYPE
1919 && tree_int_cst_equal (TYPE_SIZE (type
), TYPE_SIZE (orig
)));
1920 return fold_build1 (NOP_EXPR
, type
, arg
);
1923 if (TREE_CODE (arg
) == INTEGER_CST
)
1925 tem
= fold_convert_const (FLOAT_EXPR
, type
, arg
);
1926 if (tem
!= NULL_TREE
)
1929 else if (TREE_CODE (arg
) == REAL_CST
)
1931 tem
= fold_convert_const (NOP_EXPR
, type
, arg
);
1932 if (tem
!= NULL_TREE
)
1936 switch (TREE_CODE (orig
))
1938 case INTEGER_TYPE
: case CHAR_TYPE
:
1939 case BOOLEAN_TYPE
: case ENUMERAL_TYPE
:
1940 case POINTER_TYPE
: case REFERENCE_TYPE
:
1941 return fold_build1 (FLOAT_EXPR
, type
, arg
);
1944 return fold_build1 (flag_float_store
? CONVERT_EXPR
: NOP_EXPR
,
1948 tem
= fold_build1 (REALPART_EXPR
, TREE_TYPE (orig
), arg
);
1949 return fold_convert (type
, tem
);
1956 switch (TREE_CODE (orig
))
1958 case INTEGER_TYPE
: case CHAR_TYPE
:
1959 case BOOLEAN_TYPE
: case ENUMERAL_TYPE
:
1960 case POINTER_TYPE
: case REFERENCE_TYPE
:
1962 return build2 (COMPLEX_EXPR
, type
,
1963 fold_convert (TREE_TYPE (type
), arg
),
1964 fold_convert (TREE_TYPE (type
), integer_zero_node
));
1969 if (TREE_CODE (arg
) == COMPLEX_EXPR
)
1971 rpart
= fold_convert (TREE_TYPE (type
), TREE_OPERAND (arg
, 0));
1972 ipart
= fold_convert (TREE_TYPE (type
), TREE_OPERAND (arg
, 1));
1973 return fold_build2 (COMPLEX_EXPR
, type
, rpart
, ipart
);
1976 arg
= save_expr (arg
);
1977 rpart
= fold_build1 (REALPART_EXPR
, TREE_TYPE (orig
), arg
);
1978 ipart
= fold_build1 (IMAGPART_EXPR
, TREE_TYPE (orig
), arg
);
1979 rpart
= fold_convert (TREE_TYPE (type
), rpart
);
1980 ipart
= fold_convert (TREE_TYPE (type
), ipart
);
1981 return fold_build2 (COMPLEX_EXPR
, type
, rpart
, ipart
);
1989 if (integer_zerop (arg
))
1990 return build_zero_vector (type
);
1991 gcc_assert (tree_int_cst_equal (TYPE_SIZE (type
), TYPE_SIZE (orig
)));
1992 gcc_assert (INTEGRAL_TYPE_P (orig
) || POINTER_TYPE_P (orig
)
1993 || TREE_CODE (orig
) == VECTOR_TYPE
);
1994 return fold_build1 (NOP_EXPR
, type
, arg
);
1997 return fold_build1 (CONVERT_EXPR
, type
, fold_ignored_result (arg
));
2004 /* Return false if expr can be assumed not to be an value, true
2008 maybe_lvalue_p (tree x
)
2010 /* We only need to wrap lvalue tree codes. */
2011 switch (TREE_CODE (x
))
2022 case ALIGN_INDIRECT_REF
:
2023 case MISALIGNED_INDIRECT_REF
:
2025 case ARRAY_RANGE_REF
:
2031 case PREINCREMENT_EXPR
:
2032 case PREDECREMENT_EXPR
:
2034 case TRY_CATCH_EXPR
:
2035 case WITH_CLEANUP_EXPR
:
2046 /* Assume the worst for front-end tree codes. */
2047 if ((int)TREE_CODE (x
) >= NUM_TREE_CODES
)
2055 /* Return an expr equal to X but certainly not valid as an lvalue. */
2060 /* While we are in GIMPLE, NON_LVALUE_EXPR doesn't mean anything to
2065 if (! maybe_lvalue_p (x
))
2067 return build1 (NON_LVALUE_EXPR
, TREE_TYPE (x
), x
);
2070 /* Nonzero means lvalues are limited to those valid in pedantic ANSI C.
2071 Zero means allow extended lvalues. */
2073 int pedantic_lvalues
;
2075 /* When pedantic, return an expr equal to X but certainly not valid as a
2076 pedantic lvalue. Otherwise, return X. */
2079 pedantic_non_lvalue (tree x
)
2081 if (pedantic_lvalues
)
2082 return non_lvalue (x
);
2087 /* Given a tree comparison code, return the code that is the logical inverse
2088 of the given code. It is not safe to do this for floating-point
2089 comparisons, except for NE_EXPR and EQ_EXPR, so we receive a machine mode
2090 as well: if reversing the comparison is unsafe, return ERROR_MARK. */
2092 static enum tree_code
2093 invert_tree_comparison (enum tree_code code
, bool honor_nans
)
2095 if (honor_nans
&& flag_trapping_math
)
2105 return honor_nans
? UNLE_EXPR
: LE_EXPR
;
2107 return honor_nans
? UNLT_EXPR
: LT_EXPR
;
2109 return honor_nans
? UNGE_EXPR
: GE_EXPR
;
2111 return honor_nans
? UNGT_EXPR
: GT_EXPR
;
2125 return UNORDERED_EXPR
;
2126 case UNORDERED_EXPR
:
2127 return ORDERED_EXPR
;
2133 /* Similar, but return the comparison that results if the operands are
2134 swapped. This is safe for floating-point. */
2137 swap_tree_comparison (enum tree_code code
)
2158 /* Convert a comparison tree code from an enum tree_code representation
2159 into a compcode bit-based encoding. This function is the inverse of
2160 compcode_to_comparison. */
2162 static enum comparison_code
2163 comparison_to_compcode (enum tree_code code
)
2180 return COMPCODE_ORD
;
2181 case UNORDERED_EXPR
:
2182 return COMPCODE_UNORD
;
2184 return COMPCODE_UNLT
;
2186 return COMPCODE_UNEQ
;
2188 return COMPCODE_UNLE
;
2190 return COMPCODE_UNGT
;
2192 return COMPCODE_LTGT
;
2194 return COMPCODE_UNGE
;
2200 /* Convert a compcode bit-based encoding of a comparison operator back
2201 to GCC's enum tree_code representation. This function is the
2202 inverse of comparison_to_compcode. */
2204 static enum tree_code
2205 compcode_to_comparison (enum comparison_code code
)
2222 return ORDERED_EXPR
;
2223 case COMPCODE_UNORD
:
2224 return UNORDERED_EXPR
;
2242 /* Return a tree for the comparison which is the combination of
2243 doing the AND or OR (depending on CODE) of the two operations LCODE
2244 and RCODE on the identical operands LL_ARG and LR_ARG. Take into account
2245 the possibility of trapping if the mode has NaNs, and return NULL_TREE
2246 if this makes the transformation invalid. */
2249 combine_comparisons (enum tree_code code
, enum tree_code lcode
,
2250 enum tree_code rcode
, tree truth_type
,
2251 tree ll_arg
, tree lr_arg
)
2253 bool honor_nans
= HONOR_NANS (TYPE_MODE (TREE_TYPE (ll_arg
)));
2254 enum comparison_code lcompcode
= comparison_to_compcode (lcode
);
2255 enum comparison_code rcompcode
= comparison_to_compcode (rcode
);
2256 enum comparison_code compcode
;
2260 case TRUTH_AND_EXPR
: case TRUTH_ANDIF_EXPR
:
2261 compcode
= lcompcode
& rcompcode
;
2264 case TRUTH_OR_EXPR
: case TRUTH_ORIF_EXPR
:
2265 compcode
= lcompcode
| rcompcode
;
2274 /* Eliminate unordered comparisons, as well as LTGT and ORD
2275 which are not used unless the mode has NaNs. */
2276 compcode
&= ~COMPCODE_UNORD
;
2277 if (compcode
== COMPCODE_LTGT
)
2278 compcode
= COMPCODE_NE
;
2279 else if (compcode
== COMPCODE_ORD
)
2280 compcode
= COMPCODE_TRUE
;
2282 else if (flag_trapping_math
)
2284 /* Check that the original operation and the optimized ones will trap
2285 under the same condition. */
2286 bool ltrap
= (lcompcode
& COMPCODE_UNORD
) == 0
2287 && (lcompcode
!= COMPCODE_EQ
)
2288 && (lcompcode
!= COMPCODE_ORD
);
2289 bool rtrap
= (rcompcode
& COMPCODE_UNORD
) == 0
2290 && (rcompcode
!= COMPCODE_EQ
)
2291 && (rcompcode
!= COMPCODE_ORD
);
2292 bool trap
= (compcode
& COMPCODE_UNORD
) == 0
2293 && (compcode
!= COMPCODE_EQ
)
2294 && (compcode
!= COMPCODE_ORD
);
2296 /* In a short-circuited boolean expression the LHS might be
2297 such that the RHS, if evaluated, will never trap. For
2298 example, in ORD (x, y) && (x < y), we evaluate the RHS only
2299 if neither x nor y is NaN. (This is a mixed blessing: for
2300 example, the expression above will never trap, hence
2301 optimizing it to x < y would be invalid). */
2302 if ((code
== TRUTH_ORIF_EXPR
&& (lcompcode
& COMPCODE_UNORD
))
2303 || (code
== TRUTH_ANDIF_EXPR
&& !(lcompcode
& COMPCODE_UNORD
)))
2306 /* If the comparison was short-circuited, and only the RHS
2307 trapped, we may now generate a spurious trap. */
2309 && (code
== TRUTH_ANDIF_EXPR
|| code
== TRUTH_ORIF_EXPR
))
2312 /* If we changed the conditions that cause a trap, we lose. */
2313 if ((ltrap
|| rtrap
) != trap
)
2317 if (compcode
== COMPCODE_TRUE
)
2318 return constant_boolean_node (true, truth_type
);
2319 else if (compcode
== COMPCODE_FALSE
)
2320 return constant_boolean_node (false, truth_type
);
2322 return fold_build2 (compcode_to_comparison (compcode
),
2323 truth_type
, ll_arg
, lr_arg
);
2326 /* Return nonzero if CODE is a tree code that represents a truth value. */
2329 truth_value_p (enum tree_code code
)
2331 return (TREE_CODE_CLASS (code
) == tcc_comparison
2332 || code
== TRUTH_AND_EXPR
|| code
== TRUTH_ANDIF_EXPR
2333 || code
== TRUTH_OR_EXPR
|| code
== TRUTH_ORIF_EXPR
2334 || code
== TRUTH_XOR_EXPR
|| code
== TRUTH_NOT_EXPR
);
2337 /* Return nonzero if two operands (typically of the same tree node)
2338 are necessarily equal. If either argument has side-effects this
2339 function returns zero. FLAGS modifies behavior as follows:
2341 If OEP_ONLY_CONST is set, only return nonzero for constants.
2342 This function tests whether the operands are indistinguishable;
2343 it does not test whether they are equal using C's == operation.
2344 The distinction is important for IEEE floating point, because
2345 (1) -0.0 and 0.0 are distinguishable, but -0.0==0.0, and
2346 (2) two NaNs may be indistinguishable, but NaN!=NaN.
2348 If OEP_ONLY_CONST is unset, a VAR_DECL is considered equal to itself
2349 even though it may hold multiple values during a function.
2350 This is because a GCC tree node guarantees that nothing else is
2351 executed between the evaluation of its "operands" (which may often
2352 be evaluated in arbitrary order). Hence if the operands themselves
2353 don't side-effect, the VAR_DECLs, PARM_DECLs etc... must hold the
2354 same value in each operand/subexpression. Hence leaving OEP_ONLY_CONST
2355 unset means assuming isochronic (or instantaneous) tree equivalence.
2356 Unless comparing arbitrary expression trees, such as from different
2357 statements, this flag can usually be left unset.
2359 If OEP_PURE_SAME is set, then pure functions with identical arguments
2360 are considered the same. It is used when the caller has other ways
2361 to ensure that global memory is unchanged in between. */
2364 operand_equal_p (tree arg0
, tree arg1
, unsigned int flags
)
2366 /* If either is ERROR_MARK, they aren't equal. */
2367 if (TREE_CODE (arg0
) == ERROR_MARK
|| TREE_CODE (arg1
) == ERROR_MARK
)
2370 /* If both types don't have the same signedness, then we can't consider
2371 them equal. We must check this before the STRIP_NOPS calls
2372 because they may change the signedness of the arguments. */
2373 if (TYPE_UNSIGNED (TREE_TYPE (arg0
)) != TYPE_UNSIGNED (TREE_TYPE (arg1
)))
2379 if (TREE_CODE (arg0
) != TREE_CODE (arg1
)
2380 /* This is needed for conversions and for COMPONENT_REF.
2381 Might as well play it safe and always test this. */
2382 || TREE_CODE (TREE_TYPE (arg0
)) == ERROR_MARK
2383 || TREE_CODE (TREE_TYPE (arg1
)) == ERROR_MARK
2384 || TYPE_MODE (TREE_TYPE (arg0
)) != TYPE_MODE (TREE_TYPE (arg1
)))
2387 /* If ARG0 and ARG1 are the same SAVE_EXPR, they are necessarily equal.
2388 We don't care about side effects in that case because the SAVE_EXPR
2389 takes care of that for us. In all other cases, two expressions are
2390 equal if they have no side effects. If we have two identical
2391 expressions with side effects that should be treated the same due
2392 to the only side effects being identical SAVE_EXPR's, that will
2393 be detected in the recursive calls below. */
2394 if (arg0
== arg1
&& ! (flags
& OEP_ONLY_CONST
)
2395 && (TREE_CODE (arg0
) == SAVE_EXPR
2396 || (! TREE_SIDE_EFFECTS (arg0
) && ! TREE_SIDE_EFFECTS (arg1
))))
2399 /* Next handle constant cases, those for which we can return 1 even
2400 if ONLY_CONST is set. */
2401 if (TREE_CONSTANT (arg0
) && TREE_CONSTANT (arg1
))
2402 switch (TREE_CODE (arg0
))
2405 return (! TREE_CONSTANT_OVERFLOW (arg0
)
2406 && ! TREE_CONSTANT_OVERFLOW (arg1
)
2407 && tree_int_cst_equal (arg0
, arg1
));
2410 return (! TREE_CONSTANT_OVERFLOW (arg0
)
2411 && ! TREE_CONSTANT_OVERFLOW (arg1
)
2412 && REAL_VALUES_IDENTICAL (TREE_REAL_CST (arg0
),
2413 TREE_REAL_CST (arg1
)));
2419 if (TREE_CONSTANT_OVERFLOW (arg0
)
2420 || TREE_CONSTANT_OVERFLOW (arg1
))
2423 v1
= TREE_VECTOR_CST_ELTS (arg0
);
2424 v2
= TREE_VECTOR_CST_ELTS (arg1
);
2427 if (!operand_equal_p (TREE_VALUE (v1
), TREE_VALUE (v2
),
2430 v1
= TREE_CHAIN (v1
);
2431 v2
= TREE_CHAIN (v2
);
2438 return (operand_equal_p (TREE_REALPART (arg0
), TREE_REALPART (arg1
),
2440 && operand_equal_p (TREE_IMAGPART (arg0
), TREE_IMAGPART (arg1
),
2444 return (TREE_STRING_LENGTH (arg0
) == TREE_STRING_LENGTH (arg1
)
2445 && ! memcmp (TREE_STRING_POINTER (arg0
),
2446 TREE_STRING_POINTER (arg1
),
2447 TREE_STRING_LENGTH (arg0
)));
2450 return operand_equal_p (TREE_OPERAND (arg0
, 0), TREE_OPERAND (arg1
, 0),
2456 if (flags
& OEP_ONLY_CONST
)
2459 /* Define macros to test an operand from arg0 and arg1 for equality and a
2460 variant that allows null and views null as being different from any
2461 non-null value. In the latter case, if either is null, the both
2462 must be; otherwise, do the normal comparison. */
2463 #define OP_SAME(N) operand_equal_p (TREE_OPERAND (arg0, N), \
2464 TREE_OPERAND (arg1, N), flags)
2466 #define OP_SAME_WITH_NULL(N) \
2467 ((!TREE_OPERAND (arg0, N) || !TREE_OPERAND (arg1, N)) \
2468 ? TREE_OPERAND (arg0, N) == TREE_OPERAND (arg1, N) : OP_SAME (N))
2470 switch (TREE_CODE_CLASS (TREE_CODE (arg0
)))
2473 /* Two conversions are equal only if signedness and modes match. */
2474 switch (TREE_CODE (arg0
))
2479 case FIX_TRUNC_EXPR
:
2480 case FIX_FLOOR_EXPR
:
2481 case FIX_ROUND_EXPR
:
2482 if (TYPE_UNSIGNED (TREE_TYPE (arg0
))
2483 != TYPE_UNSIGNED (TREE_TYPE (arg1
)))
2493 case tcc_comparison
:
2495 if (OP_SAME (0) && OP_SAME (1))
2498 /* For commutative ops, allow the other order. */
2499 return (commutative_tree_code (TREE_CODE (arg0
))
2500 && operand_equal_p (TREE_OPERAND (arg0
, 0),
2501 TREE_OPERAND (arg1
, 1), flags
)
2502 && operand_equal_p (TREE_OPERAND (arg0
, 1),
2503 TREE_OPERAND (arg1
, 0), flags
));
2506 /* If either of the pointer (or reference) expressions we are
2507 dereferencing contain a side effect, these cannot be equal. */
2508 if (TREE_SIDE_EFFECTS (arg0
)
2509 || TREE_SIDE_EFFECTS (arg1
))
2512 switch (TREE_CODE (arg0
))
2515 case ALIGN_INDIRECT_REF
:
2516 case MISALIGNED_INDIRECT_REF
:
2522 case ARRAY_RANGE_REF
:
2523 /* Operands 2 and 3 may be null. */
2526 && OP_SAME_WITH_NULL (2)
2527 && OP_SAME_WITH_NULL (3));
2530 /* Handle operand 2 the same as for ARRAY_REF. */
2531 return OP_SAME (0) && OP_SAME (1) && OP_SAME_WITH_NULL (2);
2534 return OP_SAME (0) && OP_SAME (1) && OP_SAME (2);
2540 case tcc_expression
:
2541 switch (TREE_CODE (arg0
))
2544 case TRUTH_NOT_EXPR
:
2547 case TRUTH_ANDIF_EXPR
:
2548 case TRUTH_ORIF_EXPR
:
2549 return OP_SAME (0) && OP_SAME (1);
2551 case TRUTH_AND_EXPR
:
2553 case TRUTH_XOR_EXPR
:
2554 if (OP_SAME (0) && OP_SAME (1))
2557 /* Otherwise take into account this is a commutative operation. */
2558 return (operand_equal_p (TREE_OPERAND (arg0
, 0),
2559 TREE_OPERAND (arg1
, 1), flags
)
2560 && operand_equal_p (TREE_OPERAND (arg0
, 1),
2561 TREE_OPERAND (arg1
, 0), flags
));
2564 /* If the CALL_EXPRs call different functions, then they
2565 clearly can not be equal. */
2570 unsigned int cef
= call_expr_flags (arg0
);
2571 if (flags
& OEP_PURE_SAME
)
2572 cef
&= ECF_CONST
| ECF_PURE
;
2579 /* Now see if all the arguments are the same. operand_equal_p
2580 does not handle TREE_LIST, so we walk the operands here
2581 feeding them to operand_equal_p. */
2582 arg0
= TREE_OPERAND (arg0
, 1);
2583 arg1
= TREE_OPERAND (arg1
, 1);
2584 while (arg0
&& arg1
)
2586 if (! operand_equal_p (TREE_VALUE (arg0
), TREE_VALUE (arg1
),
2590 arg0
= TREE_CHAIN (arg0
);
2591 arg1
= TREE_CHAIN (arg1
);
2594 /* If we get here and both argument lists are exhausted
2595 then the CALL_EXPRs are equal. */
2596 return ! (arg0
|| arg1
);
2602 case tcc_declaration
:
2603 /* Consider __builtin_sqrt equal to sqrt. */
2604 return (TREE_CODE (arg0
) == FUNCTION_DECL
2605 && DECL_BUILT_IN (arg0
) && DECL_BUILT_IN (arg1
)
2606 && DECL_BUILT_IN_CLASS (arg0
) == DECL_BUILT_IN_CLASS (arg1
)
2607 && DECL_FUNCTION_CODE (arg0
) == DECL_FUNCTION_CODE (arg1
));
2614 #undef OP_SAME_WITH_NULL
2617 /* Similar to operand_equal_p, but see if ARG0 might have been made by
2618 shorten_compare from ARG1 when ARG1 was being compared with OTHER.
2620 When in doubt, return 0. */
2623 operand_equal_for_comparison_p (tree arg0
, tree arg1
, tree other
)
2625 int unsignedp1
, unsignedpo
;
2626 tree primarg0
, primarg1
, primother
;
2627 unsigned int correct_width
;
2629 if (operand_equal_p (arg0
, arg1
, 0))
2632 if (! INTEGRAL_TYPE_P (TREE_TYPE (arg0
))
2633 || ! INTEGRAL_TYPE_P (TREE_TYPE (arg1
)))
2636 /* Discard any conversions that don't change the modes of ARG0 and ARG1
2637 and see if the inner values are the same. This removes any
2638 signedness comparison, which doesn't matter here. */
2639 primarg0
= arg0
, primarg1
= arg1
;
2640 STRIP_NOPS (primarg0
);
2641 STRIP_NOPS (primarg1
);
2642 if (operand_equal_p (primarg0
, primarg1
, 0))
2645 /* Duplicate what shorten_compare does to ARG1 and see if that gives the
2646 actual comparison operand, ARG0.
2648 First throw away any conversions to wider types
2649 already present in the operands. */
2651 primarg1
= get_narrower (arg1
, &unsignedp1
);
2652 primother
= get_narrower (other
, &unsignedpo
);
2654 correct_width
= TYPE_PRECISION (TREE_TYPE (arg1
));
2655 if (unsignedp1
== unsignedpo
2656 && TYPE_PRECISION (TREE_TYPE (primarg1
)) < correct_width
2657 && TYPE_PRECISION (TREE_TYPE (primother
)) < correct_width
)
2659 tree type
= TREE_TYPE (arg0
);
2661 /* Make sure shorter operand is extended the right way
2662 to match the longer operand. */
2663 primarg1
= fold_convert (lang_hooks
.types
.signed_or_unsigned_type
2664 (unsignedp1
, TREE_TYPE (primarg1
)), primarg1
);
2666 if (operand_equal_p (arg0
, fold_convert (type
, primarg1
), 0))
2673 /* See if ARG is an expression that is either a comparison or is performing
2674 arithmetic on comparisons. The comparisons must only be comparing
2675 two different values, which will be stored in *CVAL1 and *CVAL2; if
2676 they are nonzero it means that some operands have already been found.
2677 No variables may be used anywhere else in the expression except in the
2678 comparisons. If SAVE_P is true it means we removed a SAVE_EXPR around
2679 the expression and save_expr needs to be called with CVAL1 and CVAL2.
2681 If this is true, return 1. Otherwise, return zero. */
2684 twoval_comparison_p (tree arg
, tree
*cval1
, tree
*cval2
, int *save_p
)
2686 enum tree_code code
= TREE_CODE (arg
);
2687 enum tree_code_class
class = TREE_CODE_CLASS (code
);
2689 /* We can handle some of the tcc_expression cases here. */
2690 if (class == tcc_expression
&& code
== TRUTH_NOT_EXPR
)
2692 else if (class == tcc_expression
2693 && (code
== TRUTH_ANDIF_EXPR
|| code
== TRUTH_ORIF_EXPR
2694 || code
== COMPOUND_EXPR
))
2697 else if (class == tcc_expression
&& code
== SAVE_EXPR
2698 && ! TREE_SIDE_EFFECTS (TREE_OPERAND (arg
, 0)))
2700 /* If we've already found a CVAL1 or CVAL2, this expression is
2701 two complex to handle. */
2702 if (*cval1
|| *cval2
)
2712 return twoval_comparison_p (TREE_OPERAND (arg
, 0), cval1
, cval2
, save_p
);
2715 return (twoval_comparison_p (TREE_OPERAND (arg
, 0), cval1
, cval2
, save_p
)
2716 && twoval_comparison_p (TREE_OPERAND (arg
, 1),
2717 cval1
, cval2
, save_p
));
2722 case tcc_expression
:
2723 if (code
== COND_EXPR
)
2724 return (twoval_comparison_p (TREE_OPERAND (arg
, 0),
2725 cval1
, cval2
, save_p
)
2726 && twoval_comparison_p (TREE_OPERAND (arg
, 1),
2727 cval1
, cval2
, save_p
)
2728 && twoval_comparison_p (TREE_OPERAND (arg
, 2),
2729 cval1
, cval2
, save_p
));
2732 case tcc_comparison
:
2733 /* First see if we can handle the first operand, then the second. For
2734 the second operand, we know *CVAL1 can't be zero. It must be that
2735 one side of the comparison is each of the values; test for the
2736 case where this isn't true by failing if the two operands
2739 if (operand_equal_p (TREE_OPERAND (arg
, 0),
2740 TREE_OPERAND (arg
, 1), 0))
2744 *cval1
= TREE_OPERAND (arg
, 0);
2745 else if (operand_equal_p (*cval1
, TREE_OPERAND (arg
, 0), 0))
2747 else if (*cval2
== 0)
2748 *cval2
= TREE_OPERAND (arg
, 0);
2749 else if (operand_equal_p (*cval2
, TREE_OPERAND (arg
, 0), 0))
2754 if (operand_equal_p (*cval1
, TREE_OPERAND (arg
, 1), 0))
2756 else if (*cval2
== 0)
2757 *cval2
= TREE_OPERAND (arg
, 1);
2758 else if (operand_equal_p (*cval2
, TREE_OPERAND (arg
, 1), 0))
2770 /* ARG is a tree that is known to contain just arithmetic operations and
2771 comparisons. Evaluate the operations in the tree substituting NEW0 for
2772 any occurrence of OLD0 as an operand of a comparison and likewise for
2776 eval_subst (tree arg
, tree old0
, tree new0
, tree old1
, tree new1
)
2778 tree type
= TREE_TYPE (arg
);
2779 enum tree_code code
= TREE_CODE (arg
);
2780 enum tree_code_class
class = TREE_CODE_CLASS (code
);
2782 /* We can handle some of the tcc_expression cases here. */
2783 if (class == tcc_expression
&& code
== TRUTH_NOT_EXPR
)
2785 else if (class == tcc_expression
2786 && (code
== TRUTH_ANDIF_EXPR
|| code
== TRUTH_ORIF_EXPR
))
2792 return fold_build1 (code
, type
,
2793 eval_subst (TREE_OPERAND (arg
, 0),
2794 old0
, new0
, old1
, new1
));
2797 return fold_build2 (code
, type
,
2798 eval_subst (TREE_OPERAND (arg
, 0),
2799 old0
, new0
, old1
, new1
),
2800 eval_subst (TREE_OPERAND (arg
, 1),
2801 old0
, new0
, old1
, new1
));
2803 case tcc_expression
:
2807 return eval_subst (TREE_OPERAND (arg
, 0), old0
, new0
, old1
, new1
);
2810 return eval_subst (TREE_OPERAND (arg
, 1), old0
, new0
, old1
, new1
);
2813 return fold_build3 (code
, type
,
2814 eval_subst (TREE_OPERAND (arg
, 0),
2815 old0
, new0
, old1
, new1
),
2816 eval_subst (TREE_OPERAND (arg
, 1),
2817 old0
, new0
, old1
, new1
),
2818 eval_subst (TREE_OPERAND (arg
, 2),
2819 old0
, new0
, old1
, new1
));
2823 /* Fall through - ??? */
2825 case tcc_comparison
:
2827 tree arg0
= TREE_OPERAND (arg
, 0);
2828 tree arg1
= TREE_OPERAND (arg
, 1);
2830 /* We need to check both for exact equality and tree equality. The
2831 former will be true if the operand has a side-effect. In that
2832 case, we know the operand occurred exactly once. */
2834 if (arg0
== old0
|| operand_equal_p (arg0
, old0
, 0))
2836 else if (arg0
== old1
|| operand_equal_p (arg0
, old1
, 0))
2839 if (arg1
== old0
|| operand_equal_p (arg1
, old0
, 0))
2841 else if (arg1
== old1
|| operand_equal_p (arg1
, old1
, 0))
2844 return fold_build2 (code
, type
, arg0
, arg1
);
2852 /* Return a tree for the case when the result of an expression is RESULT
2853 converted to TYPE and OMITTED was previously an operand of the expression
2854 but is now not needed (e.g., we folded OMITTED * 0).
2856 If OMITTED has side effects, we must evaluate it. Otherwise, just do
2857 the conversion of RESULT to TYPE. */
2860 omit_one_operand (tree type
, tree result
, tree omitted
)
2862 tree t
= fold_convert (type
, result
);
2864 if (TREE_SIDE_EFFECTS (omitted
))
2865 return build2 (COMPOUND_EXPR
, type
, fold_ignored_result (omitted
), t
);
2867 return non_lvalue (t
);
2870 /* Similar, but call pedantic_non_lvalue instead of non_lvalue. */
2873 pedantic_omit_one_operand (tree type
, tree result
, tree omitted
)
2875 tree t
= fold_convert (type
, result
);
2877 if (TREE_SIDE_EFFECTS (omitted
))
2878 return build2 (COMPOUND_EXPR
, type
, fold_ignored_result (omitted
), t
);
2880 return pedantic_non_lvalue (t
);
2883 /* Return a tree for the case when the result of an expression is RESULT
2884 converted to TYPE and OMITTED1 and OMITTED2 were previously operands
2885 of the expression but are now not needed.
2887 If OMITTED1 or OMITTED2 has side effects, they must be evaluated.
2888 If both OMITTED1 and OMITTED2 have side effects, OMITTED1 is
2889 evaluated before OMITTED2. Otherwise, if neither has side effects,
2890 just do the conversion of RESULT to TYPE. */
2893 omit_two_operands (tree type
, tree result
, tree omitted1
, tree omitted2
)
2895 tree t
= fold_convert (type
, result
);
2897 if (TREE_SIDE_EFFECTS (omitted2
))
2898 t
= build2 (COMPOUND_EXPR
, type
, omitted2
, t
);
2899 if (TREE_SIDE_EFFECTS (omitted1
))
2900 t
= build2 (COMPOUND_EXPR
, type
, omitted1
, t
);
2902 return TREE_CODE (t
) != COMPOUND_EXPR
? non_lvalue (t
) : t
;
2906 /* Return a simplified tree node for the truth-negation of ARG. This
2907 never alters ARG itself. We assume that ARG is an operation that
2908 returns a truth value (0 or 1).
2910 FIXME: one would think we would fold the result, but it causes
2911 problems with the dominator optimizer. */
2913 invert_truthvalue (tree arg
)
2915 tree type
= TREE_TYPE (arg
);
2916 enum tree_code code
= TREE_CODE (arg
);
2918 if (code
== ERROR_MARK
)
2921 /* If this is a comparison, we can simply invert it, except for
2922 floating-point non-equality comparisons, in which case we just
2923 enclose a TRUTH_NOT_EXPR around what we have. */
2925 if (TREE_CODE_CLASS (code
) == tcc_comparison
)
2927 tree op_type
= TREE_TYPE (TREE_OPERAND (arg
, 0));
2928 if (FLOAT_TYPE_P (op_type
)
2929 && flag_trapping_math
2930 && code
!= ORDERED_EXPR
&& code
!= UNORDERED_EXPR
2931 && code
!= NE_EXPR
&& code
!= EQ_EXPR
)
2932 return build1 (TRUTH_NOT_EXPR
, type
, arg
);
2935 code
= invert_tree_comparison (code
,
2936 HONOR_NANS (TYPE_MODE (op_type
)));
2937 if (code
== ERROR_MARK
)
2938 return build1 (TRUTH_NOT_EXPR
, type
, arg
);
2940 return build2 (code
, type
,
2941 TREE_OPERAND (arg
, 0), TREE_OPERAND (arg
, 1));
2948 return constant_boolean_node (integer_zerop (arg
), type
);
2950 case TRUTH_AND_EXPR
:
2951 return build2 (TRUTH_OR_EXPR
, type
,
2952 invert_truthvalue (TREE_OPERAND (arg
, 0)),
2953 invert_truthvalue (TREE_OPERAND (arg
, 1)));
2956 return build2 (TRUTH_AND_EXPR
, type
,
2957 invert_truthvalue (TREE_OPERAND (arg
, 0)),
2958 invert_truthvalue (TREE_OPERAND (arg
, 1)));
2960 case TRUTH_XOR_EXPR
:
2961 /* Here we can invert either operand. We invert the first operand
2962 unless the second operand is a TRUTH_NOT_EXPR in which case our
2963 result is the XOR of the first operand with the inside of the
2964 negation of the second operand. */
2966 if (TREE_CODE (TREE_OPERAND (arg
, 1)) == TRUTH_NOT_EXPR
)
2967 return build2 (TRUTH_XOR_EXPR
, type
, TREE_OPERAND (arg
, 0),
2968 TREE_OPERAND (TREE_OPERAND (arg
, 1), 0));
2970 return build2 (TRUTH_XOR_EXPR
, type
,
2971 invert_truthvalue (TREE_OPERAND (arg
, 0)),
2972 TREE_OPERAND (arg
, 1));
2974 case TRUTH_ANDIF_EXPR
:
2975 return build2 (TRUTH_ORIF_EXPR
, type
,
2976 invert_truthvalue (TREE_OPERAND (arg
, 0)),
2977 invert_truthvalue (TREE_OPERAND (arg
, 1)));
2979 case TRUTH_ORIF_EXPR
:
2980 return build2 (TRUTH_ANDIF_EXPR
, type
,
2981 invert_truthvalue (TREE_OPERAND (arg
, 0)),
2982 invert_truthvalue (TREE_OPERAND (arg
, 1)));
2984 case TRUTH_NOT_EXPR
:
2985 return TREE_OPERAND (arg
, 0);
2988 return build3 (COND_EXPR
, type
, TREE_OPERAND (arg
, 0),
2989 invert_truthvalue (TREE_OPERAND (arg
, 1)),
2990 invert_truthvalue (TREE_OPERAND (arg
, 2)));
2993 return build2 (COMPOUND_EXPR
, type
, TREE_OPERAND (arg
, 0),
2994 invert_truthvalue (TREE_OPERAND (arg
, 1)));
2996 case NON_LVALUE_EXPR
:
2997 return invert_truthvalue (TREE_OPERAND (arg
, 0));
3000 if (TREE_CODE (TREE_TYPE (arg
)) == BOOLEAN_TYPE
)
3005 return build1 (TREE_CODE (arg
), type
,
3006 invert_truthvalue (TREE_OPERAND (arg
, 0)));
3009 if (!integer_onep (TREE_OPERAND (arg
, 1)))
3011 return build2 (EQ_EXPR
, type
, arg
,
3012 fold_convert (type
, integer_zero_node
));
3015 return build1 (TRUTH_NOT_EXPR
, type
, arg
);
3017 case CLEANUP_POINT_EXPR
:
3018 return build1 (CLEANUP_POINT_EXPR
, type
,
3019 invert_truthvalue (TREE_OPERAND (arg
, 0)));
3024 gcc_assert (TREE_CODE (TREE_TYPE (arg
)) == BOOLEAN_TYPE
);
3025 return build1 (TRUTH_NOT_EXPR
, type
, arg
);
3028 /* Given a bit-wise operation CODE applied to ARG0 and ARG1, see if both
3029 operands are another bit-wise operation with a common input. If so,
3030 distribute the bit operations to save an operation and possibly two if
3031 constants are involved. For example, convert
3032 (A | B) & (A | C) into A | (B & C)
3033 Further simplification will occur if B and C are constants.
3035 If this optimization cannot be done, 0 will be returned. */
3038 distribute_bit_expr (enum tree_code code
, tree type
, tree arg0
, tree arg1
)
3043 if (TREE_CODE (arg0
) != TREE_CODE (arg1
)
3044 || TREE_CODE (arg0
) == code
3045 || (TREE_CODE (arg0
) != BIT_AND_EXPR
3046 && TREE_CODE (arg0
) != BIT_IOR_EXPR
))
3049 if (operand_equal_p (TREE_OPERAND (arg0
, 0), TREE_OPERAND (arg1
, 0), 0))
3051 common
= TREE_OPERAND (arg0
, 0);
3052 left
= TREE_OPERAND (arg0
, 1);
3053 right
= TREE_OPERAND (arg1
, 1);
3055 else if (operand_equal_p (TREE_OPERAND (arg0
, 0), TREE_OPERAND (arg1
, 1), 0))
3057 common
= TREE_OPERAND (arg0
, 0);
3058 left
= TREE_OPERAND (arg0
, 1);
3059 right
= TREE_OPERAND (arg1
, 0);
3061 else if (operand_equal_p (TREE_OPERAND (arg0
, 1), TREE_OPERAND (arg1
, 0), 0))
3063 common
= TREE_OPERAND (arg0
, 1);
3064 left
= TREE_OPERAND (arg0
, 0);
3065 right
= TREE_OPERAND (arg1
, 1);
3067 else if (operand_equal_p (TREE_OPERAND (arg0
, 1), TREE_OPERAND (arg1
, 1), 0))
3069 common
= TREE_OPERAND (arg0
, 1);
3070 left
= TREE_OPERAND (arg0
, 0);
3071 right
= TREE_OPERAND (arg1
, 0);
3076 return fold_build2 (TREE_CODE (arg0
), type
, common
,
3077 fold_build2 (code
, type
, left
, right
));
3080 /* Return a BIT_FIELD_REF of type TYPE to refer to BITSIZE bits of INNER
3081 starting at BITPOS. The field is unsigned if UNSIGNEDP is nonzero. */
3084 make_bit_field_ref (tree inner
, tree type
, int bitsize
, int bitpos
,
3091 tree size
= TYPE_SIZE (TREE_TYPE (inner
));
3092 if ((INTEGRAL_TYPE_P (TREE_TYPE (inner
))
3093 || POINTER_TYPE_P (TREE_TYPE (inner
)))
3094 && host_integerp (size
, 0)
3095 && tree_low_cst (size
, 0) == bitsize
)
3096 return fold_convert (type
, inner
);
3099 result
= build3 (BIT_FIELD_REF
, type
, inner
,
3100 size_int (bitsize
), bitsize_int (bitpos
));
3102 BIT_FIELD_REF_UNSIGNED (result
) = unsignedp
;
3107 /* Optimize a bit-field compare.
3109 There are two cases: First is a compare against a constant and the
3110 second is a comparison of two items where the fields are at the same
3111 bit position relative to the start of a chunk (byte, halfword, word)
3112 large enough to contain it. In these cases we can avoid the shift
3113 implicit in bitfield extractions.
3115 For constants, we emit a compare of the shifted constant with the
3116 BIT_AND_EXPR of a mask and a byte, halfword, or word of the operand being
3117 compared. For two fields at the same position, we do the ANDs with the
3118 similar mask and compare the result of the ANDs.
3120 CODE is the comparison code, known to be either NE_EXPR or EQ_EXPR.
3121 COMPARE_TYPE is the type of the comparison, and LHS and RHS
3122 are the left and right operands of the comparison, respectively.
3124 If the optimization described above can be done, we return the resulting
3125 tree. Otherwise we return zero. */
3128 optimize_bit_field_compare (enum tree_code code
, tree compare_type
,
3131 HOST_WIDE_INT lbitpos
, lbitsize
, rbitpos
, rbitsize
, nbitpos
, nbitsize
;
3132 tree type
= TREE_TYPE (lhs
);
3133 tree signed_type
, unsigned_type
;
3134 int const_p
= TREE_CODE (rhs
) == INTEGER_CST
;
3135 enum machine_mode lmode
, rmode
, nmode
;
3136 int lunsignedp
, runsignedp
;
3137 int lvolatilep
= 0, rvolatilep
= 0;
3138 tree linner
, rinner
= NULL_TREE
;
3142 /* Get all the information about the extractions being done. If the bit size
3143 if the same as the size of the underlying object, we aren't doing an
3144 extraction at all and so can do nothing. We also don't want to
3145 do anything if the inner expression is a PLACEHOLDER_EXPR since we
3146 then will no longer be able to replace it. */
3147 linner
= get_inner_reference (lhs
, &lbitsize
, &lbitpos
, &offset
, &lmode
,
3148 &lunsignedp
, &lvolatilep
, false);
3149 if (linner
== lhs
|| lbitsize
== GET_MODE_BITSIZE (lmode
) || lbitsize
< 0
3150 || offset
!= 0 || TREE_CODE (linner
) == PLACEHOLDER_EXPR
)
3155 /* If this is not a constant, we can only do something if bit positions,
3156 sizes, and signedness are the same. */
3157 rinner
= get_inner_reference (rhs
, &rbitsize
, &rbitpos
, &offset
, &rmode
,
3158 &runsignedp
, &rvolatilep
, false);
3160 if (rinner
== rhs
|| lbitpos
!= rbitpos
|| lbitsize
!= rbitsize
3161 || lunsignedp
!= runsignedp
|| offset
!= 0
3162 || TREE_CODE (rinner
) == PLACEHOLDER_EXPR
)
3166 /* See if we can find a mode to refer to this field. We should be able to,
3167 but fail if we can't. */
3168 nmode
= get_best_mode (lbitsize
, lbitpos
,
3169 const_p
? TYPE_ALIGN (TREE_TYPE (linner
))
3170 : MIN (TYPE_ALIGN (TREE_TYPE (linner
)),
3171 TYPE_ALIGN (TREE_TYPE (rinner
))),
3172 word_mode
, lvolatilep
|| rvolatilep
);
3173 if (nmode
== VOIDmode
)
3176 /* Set signed and unsigned types of the precision of this mode for the
3178 signed_type
= lang_hooks
.types
.type_for_mode (nmode
, 0);
3179 unsigned_type
= lang_hooks
.types
.type_for_mode (nmode
, 1);
3181 /* Compute the bit position and size for the new reference and our offset
3182 within it. If the new reference is the same size as the original, we
3183 won't optimize anything, so return zero. */
3184 nbitsize
= GET_MODE_BITSIZE (nmode
);
3185 nbitpos
= lbitpos
& ~ (nbitsize
- 1);
3187 if (nbitsize
== lbitsize
)
3190 if (BYTES_BIG_ENDIAN
)
3191 lbitpos
= nbitsize
- lbitsize
- lbitpos
;
3193 /* Make the mask to be used against the extracted field. */
3194 mask
= build_int_cst (unsigned_type
, -1);
3195 mask
= force_fit_type (mask
, 0, false, false);
3196 mask
= fold_convert (unsigned_type
, mask
);
3197 mask
= const_binop (LSHIFT_EXPR
, mask
, size_int (nbitsize
- lbitsize
), 0);
3198 mask
= const_binop (RSHIFT_EXPR
, mask
,
3199 size_int (nbitsize
- lbitsize
- lbitpos
), 0);
3202 /* If not comparing with constant, just rework the comparison
3204 return build2 (code
, compare_type
,
3205 build2 (BIT_AND_EXPR
, unsigned_type
,
3206 make_bit_field_ref (linner
, unsigned_type
,
3207 nbitsize
, nbitpos
, 1),
3209 build2 (BIT_AND_EXPR
, unsigned_type
,
3210 make_bit_field_ref (rinner
, unsigned_type
,
3211 nbitsize
, nbitpos
, 1),
3214 /* Otherwise, we are handling the constant case. See if the constant is too
3215 big for the field. Warn and return a tree of for 0 (false) if so. We do
3216 this not only for its own sake, but to avoid having to test for this
3217 error case below. If we didn't, we might generate wrong code.
3219 For unsigned fields, the constant shifted right by the field length should
3220 be all zero. For signed fields, the high-order bits should agree with
3225 if (! integer_zerop (const_binop (RSHIFT_EXPR
,
3226 fold_convert (unsigned_type
, rhs
),
3227 size_int (lbitsize
), 0)))
3229 warning (0, "comparison is always %d due to width of bit-field",
3231 return constant_boolean_node (code
== NE_EXPR
, compare_type
);
3236 tree tem
= const_binop (RSHIFT_EXPR
, fold_convert (signed_type
, rhs
),
3237 size_int (lbitsize
- 1), 0);
3238 if (! integer_zerop (tem
) && ! integer_all_onesp (tem
))
3240 warning (0, "comparison is always %d due to width of bit-field",
3242 return constant_boolean_node (code
== NE_EXPR
, compare_type
);
3246 /* Single-bit compares should always be against zero. */
3247 if (lbitsize
== 1 && ! integer_zerop (rhs
))
3249 code
= code
== EQ_EXPR
? NE_EXPR
: EQ_EXPR
;
3250 rhs
= fold_convert (type
, integer_zero_node
);
3253 /* Make a new bitfield reference, shift the constant over the
3254 appropriate number of bits and mask it with the computed mask
3255 (in case this was a signed field). If we changed it, make a new one. */
3256 lhs
= make_bit_field_ref (linner
, unsigned_type
, nbitsize
, nbitpos
, 1);
3259 TREE_SIDE_EFFECTS (lhs
) = 1;
3260 TREE_THIS_VOLATILE (lhs
) = 1;
3263 rhs
= fold (const_binop (BIT_AND_EXPR
,
3264 const_binop (LSHIFT_EXPR
,
3265 fold_convert (unsigned_type
, rhs
),
3266 size_int (lbitpos
), 0),
3269 return build2 (code
, compare_type
,
3270 build2 (BIT_AND_EXPR
, unsigned_type
, lhs
, mask
),
3274 /* Subroutine for fold_truthop: decode a field reference.
3276 If EXP is a comparison reference, we return the innermost reference.
3278 *PBITSIZE is set to the number of bits in the reference, *PBITPOS is
3279 set to the starting bit number.
3281 If the innermost field can be completely contained in a mode-sized
3282 unit, *PMODE is set to that mode. Otherwise, it is set to VOIDmode.
3284 *PVOLATILEP is set to 1 if the any expression encountered is volatile;
3285 otherwise it is not changed.
3287 *PUNSIGNEDP is set to the signedness of the field.
3289 *PMASK is set to the mask used. This is either contained in a
3290 BIT_AND_EXPR or derived from the width of the field.
3292 *PAND_MASK is set to the mask found in a BIT_AND_EXPR, if any.
3294 Return 0 if this is not a component reference or is one that we can't
3295 do anything with. */
3298 decode_field_reference (tree exp
, HOST_WIDE_INT
*pbitsize
,
3299 HOST_WIDE_INT
*pbitpos
, enum machine_mode
*pmode
,
3300 int *punsignedp
, int *pvolatilep
,
3301 tree
*pmask
, tree
*pand_mask
)
3303 tree outer_type
= 0;
3305 tree mask
, inner
, offset
;
3307 unsigned int precision
;
3309 /* All the optimizations using this function assume integer fields.
3310 There are problems with FP fields since the type_for_size call
3311 below can fail for, e.g., XFmode. */
3312 if (! INTEGRAL_TYPE_P (TREE_TYPE (exp
)))
3315 /* We are interested in the bare arrangement of bits, so strip everything
3316 that doesn't affect the machine mode. However, record the type of the
3317 outermost expression if it may matter below. */
3318 if (TREE_CODE (exp
) == NOP_EXPR
3319 || TREE_CODE (exp
) == CONVERT_EXPR
3320 || TREE_CODE (exp
) == NON_LVALUE_EXPR
)
3321 outer_type
= TREE_TYPE (exp
);
3324 if (TREE_CODE (exp
) == BIT_AND_EXPR
)
3326 and_mask
= TREE_OPERAND (exp
, 1);
3327 exp
= TREE_OPERAND (exp
, 0);
3328 STRIP_NOPS (exp
); STRIP_NOPS (and_mask
);
3329 if (TREE_CODE (and_mask
) != INTEGER_CST
)
3333 inner
= get_inner_reference (exp
, pbitsize
, pbitpos
, &offset
, pmode
,
3334 punsignedp
, pvolatilep
, false);
3335 if ((inner
== exp
&& and_mask
== 0)
3336 || *pbitsize
< 0 || offset
!= 0
3337 || TREE_CODE (inner
) == PLACEHOLDER_EXPR
)
3340 /* If the number of bits in the reference is the same as the bitsize of
3341 the outer type, then the outer type gives the signedness. Otherwise
3342 (in case of a small bitfield) the signedness is unchanged. */
3343 if (outer_type
&& *pbitsize
== TYPE_PRECISION (outer_type
))
3344 *punsignedp
= TYPE_UNSIGNED (outer_type
);
3346 /* Compute the mask to access the bitfield. */
3347 unsigned_type
= lang_hooks
.types
.type_for_size (*pbitsize
, 1);
3348 precision
= TYPE_PRECISION (unsigned_type
);
3350 mask
= build_int_cst (unsigned_type
, -1);
3351 mask
= force_fit_type (mask
, 0, false, false);
3353 mask
= const_binop (LSHIFT_EXPR
, mask
, size_int (precision
- *pbitsize
), 0);
3354 mask
= const_binop (RSHIFT_EXPR
, mask
, size_int (precision
- *pbitsize
), 0);
3356 /* Merge it with the mask we found in the BIT_AND_EXPR, if any. */
3358 mask
= fold_build2 (BIT_AND_EXPR
, unsigned_type
,
3359 fold_convert (unsigned_type
, and_mask
), mask
);
3362 *pand_mask
= and_mask
;
3366 /* Return nonzero if MASK represents a mask of SIZE ones in the low-order
3370 all_ones_mask_p (tree mask
, int size
)
3372 tree type
= TREE_TYPE (mask
);
3373 unsigned int precision
= TYPE_PRECISION (type
);
3376 tmask
= build_int_cst (lang_hooks
.types
.signed_type (type
), -1);
3377 tmask
= force_fit_type (tmask
, 0, false, false);
3380 tree_int_cst_equal (mask
,
3381 const_binop (RSHIFT_EXPR
,
3382 const_binop (LSHIFT_EXPR
, tmask
,
3383 size_int (precision
- size
),
3385 size_int (precision
- size
), 0));
3388 /* Subroutine for fold: determine if VAL is the INTEGER_CONST that
3389 represents the sign bit of EXP's type. If EXP represents a sign
3390 or zero extension, also test VAL against the unextended type.
3391 The return value is the (sub)expression whose sign bit is VAL,
3392 or NULL_TREE otherwise. */
3395 sign_bit_p (tree exp
, tree val
)
3397 unsigned HOST_WIDE_INT mask_lo
, lo
;
3398 HOST_WIDE_INT mask_hi
, hi
;
3402 /* Tree EXP must have an integral type. */
3403 t
= TREE_TYPE (exp
);
3404 if (! INTEGRAL_TYPE_P (t
))
3407 /* Tree VAL must be an integer constant. */
3408 if (TREE_CODE (val
) != INTEGER_CST
3409 || TREE_CONSTANT_OVERFLOW (val
))
3412 width
= TYPE_PRECISION (t
);
3413 if (width
> HOST_BITS_PER_WIDE_INT
)
3415 hi
= (unsigned HOST_WIDE_INT
) 1 << (width
- HOST_BITS_PER_WIDE_INT
- 1);
3418 mask_hi
= ((unsigned HOST_WIDE_INT
) -1
3419 >> (2 * HOST_BITS_PER_WIDE_INT
- width
));
3425 lo
= (unsigned HOST_WIDE_INT
) 1 << (width
- 1);
3428 mask_lo
= ((unsigned HOST_WIDE_INT
) -1
3429 >> (HOST_BITS_PER_WIDE_INT
- width
));
3432 /* We mask off those bits beyond TREE_TYPE (exp) so that we can
3433 treat VAL as if it were unsigned. */
3434 if ((TREE_INT_CST_HIGH (val
) & mask_hi
) == hi
3435 && (TREE_INT_CST_LOW (val
) & mask_lo
) == lo
)
3438 /* Handle extension from a narrower type. */
3439 if (TREE_CODE (exp
) == NOP_EXPR
3440 && TYPE_PRECISION (TREE_TYPE (TREE_OPERAND (exp
, 0))) < width
)
3441 return sign_bit_p (TREE_OPERAND (exp
, 0), val
);
3446 /* Subroutine for fold_truthop: determine if an operand is simple enough
3447 to be evaluated unconditionally. */
3450 simple_operand_p (tree exp
)
3452 /* Strip any conversions that don't change the machine mode. */
3455 return (CONSTANT_CLASS_P (exp
)
3456 || TREE_CODE (exp
) == SSA_NAME
3458 && ! TREE_ADDRESSABLE (exp
)
3459 && ! TREE_THIS_VOLATILE (exp
)
3460 && ! DECL_NONLOCAL (exp
)
3461 /* Don't regard global variables as simple. They may be
3462 allocated in ways unknown to the compiler (shared memory,
3463 #pragma weak, etc). */
3464 && ! TREE_PUBLIC (exp
)
3465 && ! DECL_EXTERNAL (exp
)
3466 /* Loading a static variable is unduly expensive, but global
3467 registers aren't expensive. */
3468 && (! TREE_STATIC (exp
) || DECL_REGISTER (exp
))));
3471 /* The following functions are subroutines to fold_range_test and allow it to
3472 try to change a logical combination of comparisons into a range test.
3475 X == 2 || X == 3 || X == 4 || X == 5
3479 (unsigned) (X - 2) <= 3
3481 We describe each set of comparisons as being either inside or outside
3482 a range, using a variable named like IN_P, and then describe the
3483 range with a lower and upper bound. If one of the bounds is omitted,
3484 it represents either the highest or lowest value of the type.
3486 In the comments below, we represent a range by two numbers in brackets
3487 preceded by a "+" to designate being inside that range, or a "-" to
3488 designate being outside that range, so the condition can be inverted by
3489 flipping the prefix. An omitted bound is represented by a "-". For
3490 example, "- [-, 10]" means being outside the range starting at the lowest
3491 possible value and ending at 10, in other words, being greater than 10.
3492 The range "+ [-, -]" is always true and hence the range "- [-, -]" is
3495 We set up things so that the missing bounds are handled in a consistent
3496 manner so neither a missing bound nor "true" and "false" need to be
3497 handled using a special case. */
3499 /* Return the result of applying CODE to ARG0 and ARG1, but handle the case
3500 of ARG0 and/or ARG1 being omitted, meaning an unlimited range. UPPER0_P
3501 and UPPER1_P are nonzero if the respective argument is an upper bound
3502 and zero for a lower. TYPE, if nonzero, is the type of the result; it
3503 must be specified for a comparison. ARG1 will be converted to ARG0's
3504 type if both are specified. */
3507 range_binop (enum tree_code code
, tree type
, tree arg0
, int upper0_p
,
3508 tree arg1
, int upper1_p
)
3514 /* If neither arg represents infinity, do the normal operation.
3515 Else, if not a comparison, return infinity. Else handle the special
3516 comparison rules. Note that most of the cases below won't occur, but
3517 are handled for consistency. */
3519 if (arg0
!= 0 && arg1
!= 0)
3521 tem
= fold_build2 (code
, type
!= 0 ? type
: TREE_TYPE (arg0
),
3522 arg0
, fold_convert (TREE_TYPE (arg0
), arg1
));
3524 return TREE_CODE (tem
) == INTEGER_CST
? tem
: 0;
3527 if (TREE_CODE_CLASS (code
) != tcc_comparison
)
3530 /* Set SGN[01] to -1 if ARG[01] is a lower bound, 1 for upper, and 0
3531 for neither. In real maths, we cannot assume open ended ranges are
3532 the same. But, this is computer arithmetic, where numbers are finite.
3533 We can therefore make the transformation of any unbounded range with
3534 the value Z, Z being greater than any representable number. This permits
3535 us to treat unbounded ranges as equal. */
3536 sgn0
= arg0
!= 0 ? 0 : (upper0_p
? 1 : -1);
3537 sgn1
= arg1
!= 0 ? 0 : (upper1_p
? 1 : -1);
3541 result
= sgn0
== sgn1
;
3544 result
= sgn0
!= sgn1
;
3547 result
= sgn0
< sgn1
;
3550 result
= sgn0
<= sgn1
;
3553 result
= sgn0
> sgn1
;
3556 result
= sgn0
>= sgn1
;
3562 return constant_boolean_node (result
, type
);
3565 /* Given EXP, a logical expression, set the range it is testing into
3566 variables denoted by PIN_P, PLOW, and PHIGH. Return the expression
3567 actually being tested. *PLOW and *PHIGH will be made of the same type
3568 as the returned expression. If EXP is not a comparison, we will most
3569 likely not be returning a useful value and range. */
3572 make_range (tree exp
, int *pin_p
, tree
*plow
, tree
*phigh
)
3574 enum tree_code code
;
3575 tree arg0
= NULL_TREE
, arg1
= NULL_TREE
;
3576 tree exp_type
= NULL_TREE
, arg0_type
= NULL_TREE
;
3578 tree low
, high
, n_low
, n_high
;
3580 /* Start with simply saying "EXP != 0" and then look at the code of EXP
3581 and see if we can refine the range. Some of the cases below may not
3582 happen, but it doesn't seem worth worrying about this. We "continue"
3583 the outer loop when we've changed something; otherwise we "break"
3584 the switch, which will "break" the while. */
3587 low
= high
= fold_convert (TREE_TYPE (exp
), integer_zero_node
);
3591 code
= TREE_CODE (exp
);
3592 exp_type
= TREE_TYPE (exp
);
3594 if (IS_EXPR_CODE_CLASS (TREE_CODE_CLASS (code
)))
3596 if (TREE_CODE_LENGTH (code
) > 0)
3597 arg0
= TREE_OPERAND (exp
, 0);
3598 if (TREE_CODE_CLASS (code
) == tcc_comparison
3599 || TREE_CODE_CLASS (code
) == tcc_unary
3600 || TREE_CODE_CLASS (code
) == tcc_binary
)
3601 arg0_type
= TREE_TYPE (arg0
);
3602 if (TREE_CODE_CLASS (code
) == tcc_binary
3603 || TREE_CODE_CLASS (code
) == tcc_comparison
3604 || (TREE_CODE_CLASS (code
) == tcc_expression
3605 && TREE_CODE_LENGTH (code
) > 1))
3606 arg1
= TREE_OPERAND (exp
, 1);
3611 case TRUTH_NOT_EXPR
:
3612 in_p
= ! in_p
, exp
= arg0
;
3615 case EQ_EXPR
: case NE_EXPR
:
3616 case LT_EXPR
: case LE_EXPR
: case GE_EXPR
: case GT_EXPR
:
3617 /* We can only do something if the range is testing for zero
3618 and if the second operand is an integer constant. Note that
3619 saying something is "in" the range we make is done by
3620 complementing IN_P since it will set in the initial case of
3621 being not equal to zero; "out" is leaving it alone. */
3622 if (low
== 0 || high
== 0
3623 || ! integer_zerop (low
) || ! integer_zerop (high
)
3624 || TREE_CODE (arg1
) != INTEGER_CST
)
3629 case NE_EXPR
: /* - [c, c] */
3632 case EQ_EXPR
: /* + [c, c] */
3633 in_p
= ! in_p
, low
= high
= arg1
;
3635 case GT_EXPR
: /* - [-, c] */
3636 low
= 0, high
= arg1
;
3638 case GE_EXPR
: /* + [c, -] */
3639 in_p
= ! in_p
, low
= arg1
, high
= 0;
3641 case LT_EXPR
: /* - [c, -] */
3642 low
= arg1
, high
= 0;
3644 case LE_EXPR
: /* + [-, c] */
3645 in_p
= ! in_p
, low
= 0, high
= arg1
;
3651 /* If this is an unsigned comparison, we also know that EXP is
3652 greater than or equal to zero. We base the range tests we make
3653 on that fact, so we record it here so we can parse existing
3654 range tests. We test arg0_type since often the return type
3655 of, e.g. EQ_EXPR, is boolean. */
3656 if (TYPE_UNSIGNED (arg0_type
) && (low
== 0 || high
== 0))
3658 if (! merge_ranges (&n_in_p
, &n_low
, &n_high
,
3660 fold_convert (arg0_type
, integer_zero_node
),
3664 in_p
= n_in_p
, low
= n_low
, high
= n_high
;
3666 /* If the high bound is missing, but we have a nonzero low
3667 bound, reverse the range so it goes from zero to the low bound
3669 if (high
== 0 && low
&& ! integer_zerop (low
))
3672 high
= range_binop (MINUS_EXPR
, NULL_TREE
, low
, 0,
3673 integer_one_node
, 0);
3674 low
= fold_convert (arg0_type
, integer_zero_node
);
3682 /* (-x) IN [a,b] -> x in [-b, -a] */
3683 n_low
= range_binop (MINUS_EXPR
, exp_type
,
3684 fold_convert (exp_type
, integer_zero_node
),
3686 n_high
= range_binop (MINUS_EXPR
, exp_type
,
3687 fold_convert (exp_type
, integer_zero_node
),
3689 low
= n_low
, high
= n_high
;
3695 exp
= build2 (MINUS_EXPR
, exp_type
, negate_expr (arg0
),
3696 fold_convert (exp_type
, integer_one_node
));
3699 case PLUS_EXPR
: case MINUS_EXPR
:
3700 if (TREE_CODE (arg1
) != INTEGER_CST
)
3703 /* If EXP is signed, any overflow in the computation is undefined,
3704 so we don't worry about it so long as our computations on
3705 the bounds don't overflow. For unsigned, overflow is defined
3706 and this is exactly the right thing. */
3707 n_low
= range_binop (code
== MINUS_EXPR
? PLUS_EXPR
: MINUS_EXPR
,
3708 arg0_type
, low
, 0, arg1
, 0);
3709 n_high
= range_binop (code
== MINUS_EXPR
? PLUS_EXPR
: MINUS_EXPR
,
3710 arg0_type
, high
, 1, arg1
, 0);
3711 if ((n_low
!= 0 && TREE_OVERFLOW (n_low
))
3712 || (n_high
!= 0 && TREE_OVERFLOW (n_high
)))
3715 /* Check for an unsigned range which has wrapped around the maximum
3716 value thus making n_high < n_low, and normalize it. */
3717 if (n_low
&& n_high
&& tree_int_cst_lt (n_high
, n_low
))
3719 low
= range_binop (PLUS_EXPR
, arg0_type
, n_high
, 0,
3720 integer_one_node
, 0);
3721 high
= range_binop (MINUS_EXPR
, arg0_type
, n_low
, 0,
3722 integer_one_node
, 0);
3724 /* If the range is of the form +/- [ x+1, x ], we won't
3725 be able to normalize it. But then, it represents the
3726 whole range or the empty set, so make it
3728 if (tree_int_cst_equal (n_low
, low
)
3729 && tree_int_cst_equal (n_high
, high
))
3735 low
= n_low
, high
= n_high
;
3740 case NOP_EXPR
: case NON_LVALUE_EXPR
: case CONVERT_EXPR
:
3741 if (TYPE_PRECISION (arg0_type
) > TYPE_PRECISION (exp_type
))
3744 if (! INTEGRAL_TYPE_P (arg0_type
)
3745 || (low
!= 0 && ! int_fits_type_p (low
, arg0_type
))
3746 || (high
!= 0 && ! int_fits_type_p (high
, arg0_type
)))
3749 n_low
= low
, n_high
= high
;
3752 n_low
= fold_convert (arg0_type
, n_low
);
3755 n_high
= fold_convert (arg0_type
, n_high
);
3758 /* If we're converting arg0 from an unsigned type, to exp,
3759 a signed type, we will be doing the comparison as unsigned.
3760 The tests above have already verified that LOW and HIGH
3763 So we have to ensure that we will handle large unsigned
3764 values the same way that the current signed bounds treat
3767 if (!TYPE_UNSIGNED (exp_type
) && TYPE_UNSIGNED (arg0_type
))
3770 tree equiv_type
= lang_hooks
.types
.type_for_mode
3771 (TYPE_MODE (arg0_type
), 1);
3773 /* A range without an upper bound is, naturally, unbounded.
3774 Since convert would have cropped a very large value, use
3775 the max value for the destination type. */
3777 = TYPE_MAX_VALUE (equiv_type
) ? TYPE_MAX_VALUE (equiv_type
)
3778 : TYPE_MAX_VALUE (arg0_type
);
3780 if (TYPE_PRECISION (exp_type
) == TYPE_PRECISION (arg0_type
))
3781 high_positive
= fold_build2 (RSHIFT_EXPR
, arg0_type
,
3782 fold_convert (arg0_type
,
3784 fold_convert (arg0_type
,
3787 /* If the low bound is specified, "and" the range with the
3788 range for which the original unsigned value will be
3792 if (! merge_ranges (&n_in_p
, &n_low
, &n_high
,
3793 1, n_low
, n_high
, 1,
3794 fold_convert (arg0_type
,
3799 in_p
= (n_in_p
== in_p
);
3803 /* Otherwise, "or" the range with the range of the input
3804 that will be interpreted as negative. */
3805 if (! merge_ranges (&n_in_p
, &n_low
, &n_high
,
3806 0, n_low
, n_high
, 1,
3807 fold_convert (arg0_type
,
3812 in_p
= (in_p
!= n_in_p
);
3817 low
= n_low
, high
= n_high
;
3827 /* If EXP is a constant, we can evaluate whether this is true or false. */
3828 if (TREE_CODE (exp
) == INTEGER_CST
)
3830 in_p
= in_p
== (integer_onep (range_binop (GE_EXPR
, integer_type_node
,
3832 && integer_onep (range_binop (LE_EXPR
, integer_type_node
,
3838 *pin_p
= in_p
, *plow
= low
, *phigh
= high
;
3842 /* Given a range, LOW, HIGH, and IN_P, an expression, EXP, and a result
3843 type, TYPE, return an expression to test if EXP is in (or out of, depending
3844 on IN_P) the range. Return 0 if the test couldn't be created. */
3847 build_range_check (tree type
, tree exp
, int in_p
, tree low
, tree high
)
3849 tree etype
= TREE_TYPE (exp
);
3854 value
= build_range_check (type
, exp
, 1, low
, high
);
3856 return invert_truthvalue (value
);
3861 if (low
== 0 && high
== 0)
3862 return fold_convert (type
, integer_one_node
);
3865 return fold_build2 (LE_EXPR
, type
, exp
, high
);
3868 return fold_build2 (GE_EXPR
, type
, exp
, low
);
3870 if (operand_equal_p (low
, high
, 0))
3871 return fold_build2 (EQ_EXPR
, type
, exp
, low
);
3873 if (integer_zerop (low
))
3875 if (! TYPE_UNSIGNED (etype
))
3877 etype
= lang_hooks
.types
.unsigned_type (etype
);
3878 high
= fold_convert (etype
, high
);
3879 exp
= fold_convert (etype
, exp
);
3881 return build_range_check (type
, exp
, 1, 0, high
);
3884 /* Optimize (c>=1) && (c<=127) into (signed char)c > 0. */
3885 if (integer_onep (low
) && TREE_CODE (high
) == INTEGER_CST
)
3887 unsigned HOST_WIDE_INT lo
;
3891 prec
= TYPE_PRECISION (etype
);
3892 if (prec
<= HOST_BITS_PER_WIDE_INT
)
3895 lo
= ((unsigned HOST_WIDE_INT
) 1 << (prec
- 1)) - 1;
3899 hi
= ((HOST_WIDE_INT
) 1 << (prec
- HOST_BITS_PER_WIDE_INT
- 1)) - 1;
3900 lo
= (unsigned HOST_WIDE_INT
) -1;
3903 if (TREE_INT_CST_HIGH (high
) == hi
&& TREE_INT_CST_LOW (high
) == lo
)
3905 if (TYPE_UNSIGNED (etype
))
3907 etype
= lang_hooks
.types
.signed_type (etype
);
3908 exp
= fold_convert (etype
, exp
);
3910 return fold_build2 (GT_EXPR
, type
, exp
,
3911 fold_convert (etype
, integer_zero_node
));
3915 value
= const_binop (MINUS_EXPR
, high
, low
, 0);
3916 if (value
!= 0 && TREE_OVERFLOW (value
) && ! TYPE_UNSIGNED (etype
))
3918 tree utype
, minv
, maxv
;
3920 /* Check if (unsigned) INT_MAX + 1 == (unsigned) INT_MIN
3921 for the type in question, as we rely on this here. */
3922 switch (TREE_CODE (etype
))
3927 utype
= lang_hooks
.types
.unsigned_type (etype
);
3928 maxv
= fold_convert (utype
, TYPE_MAX_VALUE (etype
));
3929 maxv
= range_binop (PLUS_EXPR
, NULL_TREE
, maxv
, 1,
3930 integer_one_node
, 1);
3931 minv
= fold_convert (utype
, TYPE_MIN_VALUE (etype
));
3932 if (integer_zerop (range_binop (NE_EXPR
, integer_type_node
,
3936 high
= fold_convert (etype
, high
);
3937 low
= fold_convert (etype
, low
);
3938 exp
= fold_convert (etype
, exp
);
3939 value
= const_binop (MINUS_EXPR
, high
, low
, 0);
3947 if (value
!= 0 && ! TREE_OVERFLOW (value
))
3948 return build_range_check (type
,
3949 fold_build2 (MINUS_EXPR
, etype
, exp
, low
),
3950 1, fold_convert (etype
, integer_zero_node
),
3956 /* Given two ranges, see if we can merge them into one. Return 1 if we
3957 can, 0 if we can't. Set the output range into the specified parameters. */
3960 merge_ranges (int *pin_p
, tree
*plow
, tree
*phigh
, int in0_p
, tree low0
,
3961 tree high0
, int in1_p
, tree low1
, tree high1
)
3969 int lowequal
= ((low0
== 0 && low1
== 0)
3970 || integer_onep (range_binop (EQ_EXPR
, integer_type_node
,
3971 low0
, 0, low1
, 0)));
3972 int highequal
= ((high0
== 0 && high1
== 0)
3973 || integer_onep (range_binop (EQ_EXPR
, integer_type_node
,
3974 high0
, 1, high1
, 1)));
3976 /* Make range 0 be the range that starts first, or ends last if they
3977 start at the same value. Swap them if it isn't. */
3978 if (integer_onep (range_binop (GT_EXPR
, integer_type_node
,
3981 && integer_onep (range_binop (GT_EXPR
, integer_type_node
,
3982 high1
, 1, high0
, 1))))
3984 temp
= in0_p
, in0_p
= in1_p
, in1_p
= temp
;
3985 tem
= low0
, low0
= low1
, low1
= tem
;
3986 tem
= high0
, high0
= high1
, high1
= tem
;
3989 /* Now flag two cases, whether the ranges are disjoint or whether the
3990 second range is totally subsumed in the first. Note that the tests
3991 below are simplified by the ones above. */
3992 no_overlap
= integer_onep (range_binop (LT_EXPR
, integer_type_node
,
3993 high0
, 1, low1
, 0));
3994 subset
= integer_onep (range_binop (LE_EXPR
, integer_type_node
,
3995 high1
, 1, high0
, 1));
3997 /* We now have four cases, depending on whether we are including or
3998 excluding the two ranges. */
4001 /* If they don't overlap, the result is false. If the second range
4002 is a subset it is the result. Otherwise, the range is from the start
4003 of the second to the end of the first. */
4005 in_p
= 0, low
= high
= 0;
4007 in_p
= 1, low
= low1
, high
= high1
;
4009 in_p
= 1, low
= low1
, high
= high0
;
4012 else if (in0_p
&& ! in1_p
)
4014 /* If they don't overlap, the result is the first range. If they are
4015 equal, the result is false. If the second range is a subset of the
4016 first, and the ranges begin at the same place, we go from just after
4017 the end of the first range to the end of the second. If the second
4018 range is not a subset of the first, or if it is a subset and both
4019 ranges end at the same place, the range starts at the start of the
4020 first range and ends just before the second range.
4021 Otherwise, we can't describe this as a single range. */
4023 in_p
= 1, low
= low0
, high
= high0
;
4024 else if (lowequal
&& highequal
)
4025 in_p
= 0, low
= high
= 0;
4026 else if (subset
&& lowequal
)
4028 in_p
= 1, high
= high0
;
4029 low
= range_binop (PLUS_EXPR
, NULL_TREE
, high1
, 0,
4030 integer_one_node
, 0);
4032 else if (! subset
|| highequal
)
4034 in_p
= 1, low
= low0
;
4035 high
= range_binop (MINUS_EXPR
, NULL_TREE
, low1
, 0,
4036 integer_one_node
, 0);
4042 else if (! in0_p
&& in1_p
)
4044 /* If they don't overlap, the result is the second range. If the second
4045 is a subset of the first, the result is false. Otherwise,
4046 the range starts just after the first range and ends at the
4047 end of the second. */
4049 in_p
= 1, low
= low1
, high
= high1
;
4050 else if (subset
|| highequal
)
4051 in_p
= 0, low
= high
= 0;
4054 in_p
= 1, high
= high1
;
4055 low
= range_binop (PLUS_EXPR
, NULL_TREE
, high0
, 1,
4056 integer_one_node
, 0);
4062 /* The case where we are excluding both ranges. Here the complex case
4063 is if they don't overlap. In that case, the only time we have a
4064 range is if they are adjacent. If the second is a subset of the
4065 first, the result is the first. Otherwise, the range to exclude
4066 starts at the beginning of the first range and ends at the end of the
4070 if (integer_onep (range_binop (EQ_EXPR
, integer_type_node
,
4071 range_binop (PLUS_EXPR
, NULL_TREE
,
4073 integer_one_node
, 1),
4075 in_p
= 0, low
= low0
, high
= high1
;
4078 /* Canonicalize - [min, x] into - [-, x]. */
4079 if (low0
&& TREE_CODE (low0
) == INTEGER_CST
)
4080 switch (TREE_CODE (TREE_TYPE (low0
)))
4083 if (TYPE_PRECISION (TREE_TYPE (low0
))
4084 != GET_MODE_BITSIZE (TYPE_MODE (TREE_TYPE (low0
))))
4089 if (tree_int_cst_equal (low0
,
4090 TYPE_MIN_VALUE (TREE_TYPE (low0
))))
4094 if (TYPE_UNSIGNED (TREE_TYPE (low0
))
4095 && integer_zerop (low0
))
4102 /* Canonicalize - [x, max] into - [x, -]. */
4103 if (high1
&& TREE_CODE (high1
) == INTEGER_CST
)
4104 switch (TREE_CODE (TREE_TYPE (high1
)))
4107 if (TYPE_PRECISION (TREE_TYPE (high1
))
4108 != GET_MODE_BITSIZE (TYPE_MODE (TREE_TYPE (high1
))))
4113 if (tree_int_cst_equal (high1
,
4114 TYPE_MAX_VALUE (TREE_TYPE (high1
))))
4118 if (TYPE_UNSIGNED (TREE_TYPE (high1
))
4119 && integer_zerop (range_binop (PLUS_EXPR
, NULL_TREE
,
4121 integer_one_node
, 1)))
4128 /* The ranges might be also adjacent between the maximum and
4129 minimum values of the given type. For
4130 - [{min,-}, x] and - [y, {max,-}] ranges where x + 1 < y
4131 return + [x + 1, y - 1]. */
4132 if (low0
== 0 && high1
== 0)
4134 low
= range_binop (PLUS_EXPR
, NULL_TREE
, high0
, 1,
4135 integer_one_node
, 1);
4136 high
= range_binop (MINUS_EXPR
, NULL_TREE
, low1
, 0,
4137 integer_one_node
, 0);
4138 if (low
== 0 || high
== 0)
4148 in_p
= 0, low
= low0
, high
= high0
;
4150 in_p
= 0, low
= low0
, high
= high1
;
4153 *pin_p
= in_p
, *plow
= low
, *phigh
= high
;
4158 /* Subroutine of fold, looking inside expressions of the form
4159 A op B ? A : C, where ARG0, ARG1 and ARG2 are the three operands
4160 of the COND_EXPR. This function is being used also to optimize
4161 A op B ? C : A, by reversing the comparison first.
4163 Return a folded expression whose code is not a COND_EXPR
4164 anymore, or NULL_TREE if no folding opportunity is found. */
4167 fold_cond_expr_with_comparison (tree type
, tree arg0
, tree arg1
, tree arg2
)
4169 enum tree_code comp_code
= TREE_CODE (arg0
);
4170 tree arg00
= TREE_OPERAND (arg0
, 0);
4171 tree arg01
= TREE_OPERAND (arg0
, 1);
4172 tree arg1_type
= TREE_TYPE (arg1
);
4178 /* If we have A op 0 ? A : -A, consider applying the following
4181 A == 0? A : -A same as -A
4182 A != 0? A : -A same as A
4183 A >= 0? A : -A same as abs (A)
4184 A > 0? A : -A same as abs (A)
4185 A <= 0? A : -A same as -abs (A)
4186 A < 0? A : -A same as -abs (A)
4188 None of these transformations work for modes with signed
4189 zeros. If A is +/-0, the first two transformations will
4190 change the sign of the result (from +0 to -0, or vice
4191 versa). The last four will fix the sign of the result,
4192 even though the original expressions could be positive or
4193 negative, depending on the sign of A.
4195 Note that all these transformations are correct if A is
4196 NaN, since the two alternatives (A and -A) are also NaNs. */
4197 if ((FLOAT_TYPE_P (TREE_TYPE (arg01
))
4198 ? real_zerop (arg01
)
4199 : integer_zerop (arg01
))
4200 && ((TREE_CODE (arg2
) == NEGATE_EXPR
4201 && operand_equal_p (TREE_OPERAND (arg2
, 0), arg1
, 0))
4202 /* In the case that A is of the form X-Y, '-A' (arg2) may
4203 have already been folded to Y-X, check for that. */
4204 || (TREE_CODE (arg1
) == MINUS_EXPR
4205 && TREE_CODE (arg2
) == MINUS_EXPR
4206 && operand_equal_p (TREE_OPERAND (arg1
, 0),
4207 TREE_OPERAND (arg2
, 1), 0)
4208 && operand_equal_p (TREE_OPERAND (arg1
, 1),
4209 TREE_OPERAND (arg2
, 0), 0))))
4214 tem
= fold_convert (arg1_type
, arg1
);
4215 return pedantic_non_lvalue (fold_convert (type
, negate_expr (tem
)));
4218 return pedantic_non_lvalue (fold_convert (type
, arg1
));
4221 if (flag_trapping_math
)
4226 if (TYPE_UNSIGNED (TREE_TYPE (arg1
)))
4227 arg1
= fold_convert (lang_hooks
.types
.signed_type
4228 (TREE_TYPE (arg1
)), arg1
);
4229 tem
= fold_build1 (ABS_EXPR
, TREE_TYPE (arg1
), arg1
);
4230 return pedantic_non_lvalue (fold_convert (type
, tem
));
4233 if (flag_trapping_math
)
4237 if (TYPE_UNSIGNED (TREE_TYPE (arg1
)))
4238 arg1
= fold_convert (lang_hooks
.types
.signed_type
4239 (TREE_TYPE (arg1
)), arg1
);
4240 tem
= fold_build1 (ABS_EXPR
, TREE_TYPE (arg1
), arg1
);
4241 return negate_expr (fold_convert (type
, tem
));
4243 gcc_assert (TREE_CODE_CLASS (comp_code
) == tcc_comparison
);
4247 /* A != 0 ? A : 0 is simply A, unless A is -0. Likewise
4248 A == 0 ? A : 0 is always 0 unless A is -0. Note that
4249 both transformations are correct when A is NaN: A != 0
4250 is then true, and A == 0 is false. */
4252 if (integer_zerop (arg01
) && integer_zerop (arg2
))
4254 if (comp_code
== NE_EXPR
)
4255 return pedantic_non_lvalue (fold_convert (type
, arg1
));
4256 else if (comp_code
== EQ_EXPR
)
4257 return fold_convert (type
, integer_zero_node
);
4260 /* Try some transformations of A op B ? A : B.
4262 A == B? A : B same as B
4263 A != B? A : B same as A
4264 A >= B? A : B same as max (A, B)
4265 A > B? A : B same as max (B, A)
4266 A <= B? A : B same as min (A, B)
4267 A < B? A : B same as min (B, A)
4269 As above, these transformations don't work in the presence
4270 of signed zeros. For example, if A and B are zeros of
4271 opposite sign, the first two transformations will change
4272 the sign of the result. In the last four, the original
4273 expressions give different results for (A=+0, B=-0) and
4274 (A=-0, B=+0), but the transformed expressions do not.
4276 The first two transformations are correct if either A or B
4277 is a NaN. In the first transformation, the condition will
4278 be false, and B will indeed be chosen. In the case of the
4279 second transformation, the condition A != B will be true,
4280 and A will be chosen.
4282 The conversions to max() and min() are not correct if B is
4283 a number and A is not. The conditions in the original
4284 expressions will be false, so all four give B. The min()
4285 and max() versions would give a NaN instead. */
4286 if (operand_equal_for_comparison_p (arg01
, arg2
, arg00
)
4287 /* Avoid these transformations if the COND_EXPR may be used
4288 as an lvalue in the C++ front-end. PR c++/19199. */
4290 || strcmp (lang_hooks
.name
, "GNU C++") != 0
4291 || ! maybe_lvalue_p (arg1
)
4292 || ! maybe_lvalue_p (arg2
)))
4294 tree comp_op0
= arg00
;
4295 tree comp_op1
= arg01
;
4296 tree comp_type
= TREE_TYPE (comp_op0
);
4298 /* Avoid adding NOP_EXPRs in case this is an lvalue. */
4299 if (TYPE_MAIN_VARIANT (comp_type
) == TYPE_MAIN_VARIANT (type
))
4309 return pedantic_non_lvalue (fold_convert (type
, arg2
));
4311 return pedantic_non_lvalue (fold_convert (type
, arg1
));
4316 /* In C++ a ?: expression can be an lvalue, so put the
4317 operand which will be used if they are equal first
4318 so that we can convert this back to the
4319 corresponding COND_EXPR. */
4320 if (!HONOR_NANS (TYPE_MODE (TREE_TYPE (arg1
))))
4322 comp_op0
= fold_convert (comp_type
, comp_op0
);
4323 comp_op1
= fold_convert (comp_type
, comp_op1
);
4324 tem
= (comp_code
== LE_EXPR
|| comp_code
== UNLE_EXPR
)
4325 ? fold_build2 (MIN_EXPR
, comp_type
, comp_op0
, comp_op1
)
4326 : fold_build2 (MIN_EXPR
, comp_type
, comp_op1
, comp_op0
);
4327 return pedantic_non_lvalue (fold_convert (type
, tem
));
4334 if (!HONOR_NANS (TYPE_MODE (TREE_TYPE (arg1
))))
4336 comp_op0
= fold_convert (comp_type
, comp_op0
);
4337 comp_op1
= fold_convert (comp_type
, comp_op1
);
4338 tem
= (comp_code
== GE_EXPR
|| comp_code
== UNGE_EXPR
)
4339 ? fold_build2 (MAX_EXPR
, comp_type
, comp_op0
, comp_op1
)
4340 : fold_build2 (MAX_EXPR
, comp_type
, comp_op1
, comp_op0
);
4341 return pedantic_non_lvalue (fold_convert (type
, tem
));
4345 if (!HONOR_NANS (TYPE_MODE (TREE_TYPE (arg1
))))
4346 return pedantic_non_lvalue (fold_convert (type
, arg2
));
4349 if (!HONOR_NANS (TYPE_MODE (TREE_TYPE (arg1
))))
4350 return pedantic_non_lvalue (fold_convert (type
, arg1
));
4353 gcc_assert (TREE_CODE_CLASS (comp_code
) == tcc_comparison
);
4358 /* If this is A op C1 ? A : C2 with C1 and C2 constant integers,
4359 we might still be able to simplify this. For example,
4360 if C1 is one less or one more than C2, this might have started
4361 out as a MIN or MAX and been transformed by this function.
4362 Only good for INTEGER_TYPEs, because we need TYPE_MAX_VALUE. */
4364 if (INTEGRAL_TYPE_P (type
)
4365 && TREE_CODE (arg01
) == INTEGER_CST
4366 && TREE_CODE (arg2
) == INTEGER_CST
)
4370 /* We can replace A with C1 in this case. */
4371 arg1
= fold_convert (type
, arg01
);
4372 return fold_build3 (COND_EXPR
, type
, arg0
, arg1
, arg2
);
4375 /* If C1 is C2 + 1, this is min(A, C2). */
4376 if (! operand_equal_p (arg2
, TYPE_MAX_VALUE (type
),
4378 && operand_equal_p (arg01
,
4379 const_binop (PLUS_EXPR
, arg2
,
4380 integer_one_node
, 0),
4382 return pedantic_non_lvalue (fold_build2 (MIN_EXPR
,
4387 /* If C1 is C2 - 1, this is min(A, C2). */
4388 if (! operand_equal_p (arg2
, TYPE_MIN_VALUE (type
),
4390 && operand_equal_p (arg01
,
4391 const_binop (MINUS_EXPR
, arg2
,
4392 integer_one_node
, 0),
4394 return pedantic_non_lvalue (fold_build2 (MIN_EXPR
,
4399 /* If C1 is C2 - 1, this is max(A, C2). */
4400 if (! operand_equal_p (arg2
, TYPE_MIN_VALUE (type
),
4402 && operand_equal_p (arg01
,
4403 const_binop (MINUS_EXPR
, arg2
,
4404 integer_one_node
, 0),
4406 return pedantic_non_lvalue (fold_build2 (MAX_EXPR
,
4411 /* If C1 is C2 + 1, this is max(A, C2). */
4412 if (! operand_equal_p (arg2
, TYPE_MAX_VALUE (type
),
4414 && operand_equal_p (arg01
,
4415 const_binop (PLUS_EXPR
, arg2
,
4416 integer_one_node
, 0),
4418 return pedantic_non_lvalue (fold_build2 (MAX_EXPR
,
4432 #ifndef LOGICAL_OP_NON_SHORT_CIRCUIT
4433 #define LOGICAL_OP_NON_SHORT_CIRCUIT (BRANCH_COST >= 2)
4436 /* EXP is some logical combination of boolean tests. See if we can
4437 merge it into some range test. Return the new tree if so. */
4440 fold_range_test (enum tree_code code
, tree type
, tree op0
, tree op1
)
4442 int or_op
= (code
== TRUTH_ORIF_EXPR
4443 || code
== TRUTH_OR_EXPR
);
4444 int in0_p
, in1_p
, in_p
;
4445 tree low0
, low1
, low
, high0
, high1
, high
;
4446 tree lhs
= make_range (op0
, &in0_p
, &low0
, &high0
);
4447 tree rhs
= make_range (op1
, &in1_p
, &low1
, &high1
);
4450 /* If this is an OR operation, invert both sides; we will invert
4451 again at the end. */
4453 in0_p
= ! in0_p
, in1_p
= ! in1_p
;
4455 /* If both expressions are the same, if we can merge the ranges, and we
4456 can build the range test, return it or it inverted. If one of the
4457 ranges is always true or always false, consider it to be the same
4458 expression as the other. */
4459 if ((lhs
== 0 || rhs
== 0 || operand_equal_p (lhs
, rhs
, 0))
4460 && merge_ranges (&in_p
, &low
, &high
, in0_p
, low0
, high0
,
4462 && 0 != (tem
= (build_range_check (type
,
4464 : rhs
!= 0 ? rhs
: integer_zero_node
,
4466 return or_op
? invert_truthvalue (tem
) : tem
;
4468 /* On machines where the branch cost is expensive, if this is a
4469 short-circuited branch and the underlying object on both sides
4470 is the same, make a non-short-circuit operation. */
4471 else if (LOGICAL_OP_NON_SHORT_CIRCUIT
4472 && lhs
!= 0 && rhs
!= 0
4473 && (code
== TRUTH_ANDIF_EXPR
4474 || code
== TRUTH_ORIF_EXPR
)
4475 && operand_equal_p (lhs
, rhs
, 0))
4477 /* If simple enough, just rewrite. Otherwise, make a SAVE_EXPR
4478 unless we are at top level or LHS contains a PLACEHOLDER_EXPR, in
4479 which cases we can't do this. */
4480 if (simple_operand_p (lhs
))
4481 return build2 (code
== TRUTH_ANDIF_EXPR
4482 ? TRUTH_AND_EXPR
: TRUTH_OR_EXPR
,
4485 else if (lang_hooks
.decls
.global_bindings_p () == 0
4486 && ! CONTAINS_PLACEHOLDER_P (lhs
))
4488 tree common
= save_expr (lhs
);
4490 if (0 != (lhs
= build_range_check (type
, common
,
4491 or_op
? ! in0_p
: in0_p
,
4493 && (0 != (rhs
= build_range_check (type
, common
,
4494 or_op
? ! in1_p
: in1_p
,
4496 return build2 (code
== TRUTH_ANDIF_EXPR
4497 ? TRUTH_AND_EXPR
: TRUTH_OR_EXPR
,
4505 /* Subroutine for fold_truthop: C is an INTEGER_CST interpreted as a P
4506 bit value. Arrange things so the extra bits will be set to zero if and
4507 only if C is signed-extended to its full width. If MASK is nonzero,
4508 it is an INTEGER_CST that should be AND'ed with the extra bits. */
4511 unextend (tree c
, int p
, int unsignedp
, tree mask
)
4513 tree type
= TREE_TYPE (c
);
4514 int modesize
= GET_MODE_BITSIZE (TYPE_MODE (type
));
4517 if (p
== modesize
|| unsignedp
)
4520 /* We work by getting just the sign bit into the low-order bit, then
4521 into the high-order bit, then sign-extend. We then XOR that value
4523 temp
= const_binop (RSHIFT_EXPR
, c
, size_int (p
- 1), 0);
4524 temp
= const_binop (BIT_AND_EXPR
, temp
, size_int (1), 0);
4526 /* We must use a signed type in order to get an arithmetic right shift.
4527 However, we must also avoid introducing accidental overflows, so that
4528 a subsequent call to integer_zerop will work. Hence we must
4529 do the type conversion here. At this point, the constant is either
4530 zero or one, and the conversion to a signed type can never overflow.
4531 We could get an overflow if this conversion is done anywhere else. */
4532 if (TYPE_UNSIGNED (type
))
4533 temp
= fold_convert (lang_hooks
.types
.signed_type (type
), temp
);
4535 temp
= const_binop (LSHIFT_EXPR
, temp
, size_int (modesize
- 1), 0);
4536 temp
= const_binop (RSHIFT_EXPR
, temp
, size_int (modesize
- p
- 1), 0);
4538 temp
= const_binop (BIT_AND_EXPR
, temp
,
4539 fold_convert (TREE_TYPE (c
), mask
), 0);
4540 /* If necessary, convert the type back to match the type of C. */
4541 if (TYPE_UNSIGNED (type
))
4542 temp
= fold_convert (type
, temp
);
4544 return fold_convert (type
, const_binop (BIT_XOR_EXPR
, c
, temp
, 0));
4547 /* Find ways of folding logical expressions of LHS and RHS:
4548 Try to merge two comparisons to the same innermost item.
4549 Look for range tests like "ch >= '0' && ch <= '9'".
4550 Look for combinations of simple terms on machines with expensive branches
4551 and evaluate the RHS unconditionally.
4553 For example, if we have p->a == 2 && p->b == 4 and we can make an
4554 object large enough to span both A and B, we can do this with a comparison
4555 against the object ANDed with the a mask.
4557 If we have p->a == q->a && p->b == q->b, we may be able to use bit masking
4558 operations to do this with one comparison.
4560 We check for both normal comparisons and the BIT_AND_EXPRs made this by
4561 function and the one above.
4563 CODE is the logical operation being done. It can be TRUTH_ANDIF_EXPR,
4564 TRUTH_AND_EXPR, TRUTH_ORIF_EXPR, or TRUTH_OR_EXPR.
4566 TRUTH_TYPE is the type of the logical operand and LHS and RHS are its
4569 We return the simplified tree or 0 if no optimization is possible. */
4572 fold_truthop (enum tree_code code
, tree truth_type
, tree lhs
, tree rhs
)
4574 /* If this is the "or" of two comparisons, we can do something if
4575 the comparisons are NE_EXPR. If this is the "and", we can do something
4576 if the comparisons are EQ_EXPR. I.e.,
4577 (a->b == 2 && a->c == 4) can become (a->new == NEW).
4579 WANTED_CODE is this operation code. For single bit fields, we can
4580 convert EQ_EXPR to NE_EXPR so we need not reject the "wrong"
4581 comparison for one-bit fields. */
4583 enum tree_code wanted_code
;
4584 enum tree_code lcode
, rcode
;
4585 tree ll_arg
, lr_arg
, rl_arg
, rr_arg
;
4586 tree ll_inner
, lr_inner
, rl_inner
, rr_inner
;
4587 HOST_WIDE_INT ll_bitsize
, ll_bitpos
, lr_bitsize
, lr_bitpos
;
4588 HOST_WIDE_INT rl_bitsize
, rl_bitpos
, rr_bitsize
, rr_bitpos
;
4589 HOST_WIDE_INT xll_bitpos
, xlr_bitpos
, xrl_bitpos
, xrr_bitpos
;
4590 HOST_WIDE_INT lnbitsize
, lnbitpos
, rnbitsize
, rnbitpos
;
4591 int ll_unsignedp
, lr_unsignedp
, rl_unsignedp
, rr_unsignedp
;
4592 enum machine_mode ll_mode
, lr_mode
, rl_mode
, rr_mode
;
4593 enum machine_mode lnmode
, rnmode
;
4594 tree ll_mask
, lr_mask
, rl_mask
, rr_mask
;
4595 tree ll_and_mask
, lr_and_mask
, rl_and_mask
, rr_and_mask
;
4596 tree l_const
, r_const
;
4597 tree lntype
, rntype
, result
;
4598 int first_bit
, end_bit
;
4601 /* Start by getting the comparison codes. Fail if anything is volatile.
4602 If one operand is a BIT_AND_EXPR with the constant one, treat it as if
4603 it were surrounded with a NE_EXPR. */
4605 if (TREE_SIDE_EFFECTS (lhs
) || TREE_SIDE_EFFECTS (rhs
))
4608 lcode
= TREE_CODE (lhs
);
4609 rcode
= TREE_CODE (rhs
);
4611 if (lcode
== BIT_AND_EXPR
&& integer_onep (TREE_OPERAND (lhs
, 1)))
4613 lhs
= build2 (NE_EXPR
, truth_type
, lhs
,
4614 fold_convert (TREE_TYPE (lhs
), integer_zero_node
));
4618 if (rcode
== BIT_AND_EXPR
&& integer_onep (TREE_OPERAND (rhs
, 1)))
4620 rhs
= build2 (NE_EXPR
, truth_type
, rhs
,
4621 fold_convert (TREE_TYPE (rhs
), integer_zero_node
));
4625 if (TREE_CODE_CLASS (lcode
) != tcc_comparison
4626 || TREE_CODE_CLASS (rcode
) != tcc_comparison
)
4629 ll_arg
= TREE_OPERAND (lhs
, 0);
4630 lr_arg
= TREE_OPERAND (lhs
, 1);
4631 rl_arg
= TREE_OPERAND (rhs
, 0);
4632 rr_arg
= TREE_OPERAND (rhs
, 1);
4634 /* Simplify (x<y) && (x==y) into (x<=y) and related optimizations. */
4635 if (simple_operand_p (ll_arg
)
4636 && simple_operand_p (lr_arg
))
4639 if (operand_equal_p (ll_arg
, rl_arg
, 0)
4640 && operand_equal_p (lr_arg
, rr_arg
, 0))
4642 result
= combine_comparisons (code
, lcode
, rcode
,
4643 truth_type
, ll_arg
, lr_arg
);
4647 else if (operand_equal_p (ll_arg
, rr_arg
, 0)
4648 && operand_equal_p (lr_arg
, rl_arg
, 0))
4650 result
= combine_comparisons (code
, lcode
,
4651 swap_tree_comparison (rcode
),
4652 truth_type
, ll_arg
, lr_arg
);
4658 code
= ((code
== TRUTH_AND_EXPR
|| code
== TRUTH_ANDIF_EXPR
)
4659 ? TRUTH_AND_EXPR
: TRUTH_OR_EXPR
);
4661 /* If the RHS can be evaluated unconditionally and its operands are
4662 simple, it wins to evaluate the RHS unconditionally on machines
4663 with expensive branches. In this case, this isn't a comparison
4664 that can be merged. Avoid doing this if the RHS is a floating-point
4665 comparison since those can trap. */
4667 if (BRANCH_COST
>= 2
4668 && ! FLOAT_TYPE_P (TREE_TYPE (rl_arg
))
4669 && simple_operand_p (rl_arg
)
4670 && simple_operand_p (rr_arg
))
4672 /* Convert (a != 0) || (b != 0) into (a | b) != 0. */
4673 if (code
== TRUTH_OR_EXPR
4674 && lcode
== NE_EXPR
&& integer_zerop (lr_arg
)
4675 && rcode
== NE_EXPR
&& integer_zerop (rr_arg
)
4676 && TREE_TYPE (ll_arg
) == TREE_TYPE (rl_arg
))
4677 return build2 (NE_EXPR
, truth_type
,
4678 build2 (BIT_IOR_EXPR
, TREE_TYPE (ll_arg
),
4680 fold_convert (TREE_TYPE (ll_arg
), integer_zero_node
));
4682 /* Convert (a == 0) && (b == 0) into (a | b) == 0. */
4683 if (code
== TRUTH_AND_EXPR
4684 && lcode
== EQ_EXPR
&& integer_zerop (lr_arg
)
4685 && rcode
== EQ_EXPR
&& integer_zerop (rr_arg
)
4686 && TREE_TYPE (ll_arg
) == TREE_TYPE (rl_arg
))
4687 return build2 (EQ_EXPR
, truth_type
,
4688 build2 (BIT_IOR_EXPR
, TREE_TYPE (ll_arg
),
4690 fold_convert (TREE_TYPE (ll_arg
), integer_zero_node
));
4692 if (LOGICAL_OP_NON_SHORT_CIRCUIT
)
4693 return build2 (code
, truth_type
, lhs
, rhs
);
4696 /* See if the comparisons can be merged. Then get all the parameters for
4699 if ((lcode
!= EQ_EXPR
&& lcode
!= NE_EXPR
)
4700 || (rcode
!= EQ_EXPR
&& rcode
!= NE_EXPR
))
4704 ll_inner
= decode_field_reference (ll_arg
,
4705 &ll_bitsize
, &ll_bitpos
, &ll_mode
,
4706 &ll_unsignedp
, &volatilep
, &ll_mask
,
4708 lr_inner
= decode_field_reference (lr_arg
,
4709 &lr_bitsize
, &lr_bitpos
, &lr_mode
,
4710 &lr_unsignedp
, &volatilep
, &lr_mask
,
4712 rl_inner
= decode_field_reference (rl_arg
,
4713 &rl_bitsize
, &rl_bitpos
, &rl_mode
,
4714 &rl_unsignedp
, &volatilep
, &rl_mask
,
4716 rr_inner
= decode_field_reference (rr_arg
,
4717 &rr_bitsize
, &rr_bitpos
, &rr_mode
,
4718 &rr_unsignedp
, &volatilep
, &rr_mask
,
4721 /* It must be true that the inner operation on the lhs of each
4722 comparison must be the same if we are to be able to do anything.
4723 Then see if we have constants. If not, the same must be true for
4725 if (volatilep
|| ll_inner
== 0 || rl_inner
== 0
4726 || ! operand_equal_p (ll_inner
, rl_inner
, 0))
4729 if (TREE_CODE (lr_arg
) == INTEGER_CST
4730 && TREE_CODE (rr_arg
) == INTEGER_CST
)
4731 l_const
= lr_arg
, r_const
= rr_arg
;
4732 else if (lr_inner
== 0 || rr_inner
== 0
4733 || ! operand_equal_p (lr_inner
, rr_inner
, 0))
4736 l_const
= r_const
= 0;
4738 /* If either comparison code is not correct for our logical operation,
4739 fail. However, we can convert a one-bit comparison against zero into
4740 the opposite comparison against that bit being set in the field. */
4742 wanted_code
= (code
== TRUTH_AND_EXPR
? EQ_EXPR
: NE_EXPR
);
4743 if (lcode
!= wanted_code
)
4745 if (l_const
&& integer_zerop (l_const
) && integer_pow2p (ll_mask
))
4747 /* Make the left operand unsigned, since we are only interested
4748 in the value of one bit. Otherwise we are doing the wrong
4757 /* This is analogous to the code for l_const above. */
4758 if (rcode
!= wanted_code
)
4760 if (r_const
&& integer_zerop (r_const
) && integer_pow2p (rl_mask
))
4769 /* After this point all optimizations will generate bit-field
4770 references, which we might not want. */
4771 if (! lang_hooks
.can_use_bit_fields_p ())
4774 /* See if we can find a mode that contains both fields being compared on
4775 the left. If we can't, fail. Otherwise, update all constants and masks
4776 to be relative to a field of that size. */
4777 first_bit
= MIN (ll_bitpos
, rl_bitpos
);
4778 end_bit
= MAX (ll_bitpos
+ ll_bitsize
, rl_bitpos
+ rl_bitsize
);
4779 lnmode
= get_best_mode (end_bit
- first_bit
, first_bit
,
4780 TYPE_ALIGN (TREE_TYPE (ll_inner
)), word_mode
,
4782 if (lnmode
== VOIDmode
)
4785 lnbitsize
= GET_MODE_BITSIZE (lnmode
);
4786 lnbitpos
= first_bit
& ~ (lnbitsize
- 1);
4787 lntype
= lang_hooks
.types
.type_for_size (lnbitsize
, 1);
4788 xll_bitpos
= ll_bitpos
- lnbitpos
, xrl_bitpos
= rl_bitpos
- lnbitpos
;
4790 if (BYTES_BIG_ENDIAN
)
4792 xll_bitpos
= lnbitsize
- xll_bitpos
- ll_bitsize
;
4793 xrl_bitpos
= lnbitsize
- xrl_bitpos
- rl_bitsize
;
4796 ll_mask
= const_binop (LSHIFT_EXPR
, fold_convert (lntype
, ll_mask
),
4797 size_int (xll_bitpos
), 0);
4798 rl_mask
= const_binop (LSHIFT_EXPR
, fold_convert (lntype
, rl_mask
),
4799 size_int (xrl_bitpos
), 0);
4803 l_const
= fold_convert (lntype
, l_const
);
4804 l_const
= unextend (l_const
, ll_bitsize
, ll_unsignedp
, ll_and_mask
);
4805 l_const
= const_binop (LSHIFT_EXPR
, l_const
, size_int (xll_bitpos
), 0);
4806 if (! integer_zerop (const_binop (BIT_AND_EXPR
, l_const
,
4807 fold_build1 (BIT_NOT_EXPR
,
4811 warning (0, "comparison is always %d", wanted_code
== NE_EXPR
);
4813 return constant_boolean_node (wanted_code
== NE_EXPR
, truth_type
);
4818 r_const
= fold_convert (lntype
, r_const
);
4819 r_const
= unextend (r_const
, rl_bitsize
, rl_unsignedp
, rl_and_mask
);
4820 r_const
= const_binop (LSHIFT_EXPR
, r_const
, size_int (xrl_bitpos
), 0);
4821 if (! integer_zerop (const_binop (BIT_AND_EXPR
, r_const
,
4822 fold_build1 (BIT_NOT_EXPR
,
4826 warning (0, "comparison is always %d", wanted_code
== NE_EXPR
);
4828 return constant_boolean_node (wanted_code
== NE_EXPR
, truth_type
);
4832 /* If the right sides are not constant, do the same for it. Also,
4833 disallow this optimization if a size or signedness mismatch occurs
4834 between the left and right sides. */
4837 if (ll_bitsize
!= lr_bitsize
|| rl_bitsize
!= rr_bitsize
4838 || ll_unsignedp
!= lr_unsignedp
|| rl_unsignedp
!= rr_unsignedp
4839 /* Make sure the two fields on the right
4840 correspond to the left without being swapped. */
4841 || ll_bitpos
- rl_bitpos
!= lr_bitpos
- rr_bitpos
)
4844 first_bit
= MIN (lr_bitpos
, rr_bitpos
);
4845 end_bit
= MAX (lr_bitpos
+ lr_bitsize
, rr_bitpos
+ rr_bitsize
);
4846 rnmode
= get_best_mode (end_bit
- first_bit
, first_bit
,
4847 TYPE_ALIGN (TREE_TYPE (lr_inner
)), word_mode
,
4849 if (rnmode
== VOIDmode
)
4852 rnbitsize
= GET_MODE_BITSIZE (rnmode
);
4853 rnbitpos
= first_bit
& ~ (rnbitsize
- 1);
4854 rntype
= lang_hooks
.types
.type_for_size (rnbitsize
, 1);
4855 xlr_bitpos
= lr_bitpos
- rnbitpos
, xrr_bitpos
= rr_bitpos
- rnbitpos
;
4857 if (BYTES_BIG_ENDIAN
)
4859 xlr_bitpos
= rnbitsize
- xlr_bitpos
- lr_bitsize
;
4860 xrr_bitpos
= rnbitsize
- xrr_bitpos
- rr_bitsize
;
4863 lr_mask
= const_binop (LSHIFT_EXPR
, fold_convert (rntype
, lr_mask
),
4864 size_int (xlr_bitpos
), 0);
4865 rr_mask
= const_binop (LSHIFT_EXPR
, fold_convert (rntype
, rr_mask
),
4866 size_int (xrr_bitpos
), 0);
4868 /* Make a mask that corresponds to both fields being compared.
4869 Do this for both items being compared. If the operands are the
4870 same size and the bits being compared are in the same position
4871 then we can do this by masking both and comparing the masked
4873 ll_mask
= const_binop (BIT_IOR_EXPR
, ll_mask
, rl_mask
, 0);
4874 lr_mask
= const_binop (BIT_IOR_EXPR
, lr_mask
, rr_mask
, 0);
4875 if (lnbitsize
== rnbitsize
&& xll_bitpos
== xlr_bitpos
)
4877 lhs
= make_bit_field_ref (ll_inner
, lntype
, lnbitsize
, lnbitpos
,
4878 ll_unsignedp
|| rl_unsignedp
);
4879 if (! all_ones_mask_p (ll_mask
, lnbitsize
))
4880 lhs
= build2 (BIT_AND_EXPR
, lntype
, lhs
, ll_mask
);
4882 rhs
= make_bit_field_ref (lr_inner
, rntype
, rnbitsize
, rnbitpos
,
4883 lr_unsignedp
|| rr_unsignedp
);
4884 if (! all_ones_mask_p (lr_mask
, rnbitsize
))
4885 rhs
= build2 (BIT_AND_EXPR
, rntype
, rhs
, lr_mask
);
4887 return build2 (wanted_code
, truth_type
, lhs
, rhs
);
4890 /* There is still another way we can do something: If both pairs of
4891 fields being compared are adjacent, we may be able to make a wider
4892 field containing them both.
4894 Note that we still must mask the lhs/rhs expressions. Furthermore,
4895 the mask must be shifted to account for the shift done by
4896 make_bit_field_ref. */
4897 if ((ll_bitsize
+ ll_bitpos
== rl_bitpos
4898 && lr_bitsize
+ lr_bitpos
== rr_bitpos
)
4899 || (ll_bitpos
== rl_bitpos
+ rl_bitsize
4900 && lr_bitpos
== rr_bitpos
+ rr_bitsize
))
4904 lhs
= make_bit_field_ref (ll_inner
, lntype
, ll_bitsize
+ rl_bitsize
,
4905 MIN (ll_bitpos
, rl_bitpos
), ll_unsignedp
);
4906 rhs
= make_bit_field_ref (lr_inner
, rntype
, lr_bitsize
+ rr_bitsize
,
4907 MIN (lr_bitpos
, rr_bitpos
), lr_unsignedp
);
4909 ll_mask
= const_binop (RSHIFT_EXPR
, ll_mask
,
4910 size_int (MIN (xll_bitpos
, xrl_bitpos
)), 0);
4911 lr_mask
= const_binop (RSHIFT_EXPR
, lr_mask
,
4912 size_int (MIN (xlr_bitpos
, xrr_bitpos
)), 0);
4914 /* Convert to the smaller type before masking out unwanted bits. */
4916 if (lntype
!= rntype
)
4918 if (lnbitsize
> rnbitsize
)
4920 lhs
= fold_convert (rntype
, lhs
);
4921 ll_mask
= fold_convert (rntype
, ll_mask
);
4924 else if (lnbitsize
< rnbitsize
)
4926 rhs
= fold_convert (lntype
, rhs
);
4927 lr_mask
= fold_convert (lntype
, lr_mask
);
4932 if (! all_ones_mask_p (ll_mask
, ll_bitsize
+ rl_bitsize
))
4933 lhs
= build2 (BIT_AND_EXPR
, type
, lhs
, ll_mask
);
4935 if (! all_ones_mask_p (lr_mask
, lr_bitsize
+ rr_bitsize
))
4936 rhs
= build2 (BIT_AND_EXPR
, type
, rhs
, lr_mask
);
4938 return build2 (wanted_code
, truth_type
, lhs
, rhs
);
4944 /* Handle the case of comparisons with constants. If there is something in
4945 common between the masks, those bits of the constants must be the same.
4946 If not, the condition is always false. Test for this to avoid generating
4947 incorrect code below. */
4948 result
= const_binop (BIT_AND_EXPR
, ll_mask
, rl_mask
, 0);
4949 if (! integer_zerop (result
)
4950 && simple_cst_equal (const_binop (BIT_AND_EXPR
, result
, l_const
, 0),
4951 const_binop (BIT_AND_EXPR
, result
, r_const
, 0)) != 1)
4953 if (wanted_code
== NE_EXPR
)
4955 warning (0, "%<or%> of unmatched not-equal tests is always 1");
4956 return constant_boolean_node (true, truth_type
);
4960 warning (0, "%<and%> of mutually exclusive equal-tests is always 0");
4961 return constant_boolean_node (false, truth_type
);
4965 /* Construct the expression we will return. First get the component
4966 reference we will make. Unless the mask is all ones the width of
4967 that field, perform the mask operation. Then compare with the
4969 result
= make_bit_field_ref (ll_inner
, lntype
, lnbitsize
, lnbitpos
,
4970 ll_unsignedp
|| rl_unsignedp
);
4972 ll_mask
= const_binop (BIT_IOR_EXPR
, ll_mask
, rl_mask
, 0);
4973 if (! all_ones_mask_p (ll_mask
, lnbitsize
))
4974 result
= build2 (BIT_AND_EXPR
, lntype
, result
, ll_mask
);
4976 return build2 (wanted_code
, truth_type
, result
,
4977 const_binop (BIT_IOR_EXPR
, l_const
, r_const
, 0));
4980 /* Optimize T, which is a comparison of a MIN_EXPR or MAX_EXPR with a
4984 optimize_minmax_comparison (enum tree_code code
, tree type
, tree op0
, tree op1
)
4987 enum tree_code op_code
;
4988 tree comp_const
= op1
;
4990 int consts_equal
, consts_lt
;
4993 STRIP_SIGN_NOPS (arg0
);
4995 op_code
= TREE_CODE (arg0
);
4996 minmax_const
= TREE_OPERAND (arg0
, 1);
4997 consts_equal
= tree_int_cst_equal (minmax_const
, comp_const
);
4998 consts_lt
= tree_int_cst_lt (minmax_const
, comp_const
);
4999 inner
= TREE_OPERAND (arg0
, 0);
5001 /* If something does not permit us to optimize, return the original tree. */
5002 if ((op_code
!= MIN_EXPR
&& op_code
!= MAX_EXPR
)
5003 || TREE_CODE (comp_const
) != INTEGER_CST
5004 || TREE_CONSTANT_OVERFLOW (comp_const
)
5005 || TREE_CODE (minmax_const
) != INTEGER_CST
5006 || TREE_CONSTANT_OVERFLOW (minmax_const
))
5009 /* Now handle all the various comparison codes. We only handle EQ_EXPR
5010 and GT_EXPR, doing the rest with recursive calls using logical
5014 case NE_EXPR
: case LT_EXPR
: case LE_EXPR
:
5016 /* FIXME: We should be able to invert code without building a
5017 scratch tree node, but doing so would require us to
5018 duplicate a part of invert_truthvalue here. */
5019 tree tem
= invert_truthvalue (build2 (code
, type
, op0
, op1
));
5020 tem
= optimize_minmax_comparison (TREE_CODE (tem
),
5022 TREE_OPERAND (tem
, 0),
5023 TREE_OPERAND (tem
, 1));
5024 return invert_truthvalue (tem
);
5029 fold_build2 (TRUTH_ORIF_EXPR
, type
,
5030 optimize_minmax_comparison
5031 (EQ_EXPR
, type
, arg0
, comp_const
),
5032 optimize_minmax_comparison
5033 (GT_EXPR
, type
, arg0
, comp_const
));
5036 if (op_code
== MAX_EXPR
&& consts_equal
)
5037 /* MAX (X, 0) == 0 -> X <= 0 */
5038 return fold_build2 (LE_EXPR
, type
, inner
, comp_const
);
5040 else if (op_code
== MAX_EXPR
&& consts_lt
)
5041 /* MAX (X, 0) == 5 -> X == 5 */
5042 return fold_build2 (EQ_EXPR
, type
, inner
, comp_const
);
5044 else if (op_code
== MAX_EXPR
)
5045 /* MAX (X, 0) == -1 -> false */
5046 return omit_one_operand (type
, integer_zero_node
, inner
);
5048 else if (consts_equal
)
5049 /* MIN (X, 0) == 0 -> X >= 0 */
5050 return fold_build2 (GE_EXPR
, type
, inner
, comp_const
);
5053 /* MIN (X, 0) == 5 -> false */
5054 return omit_one_operand (type
, integer_zero_node
, inner
);
5057 /* MIN (X, 0) == -1 -> X == -1 */
5058 return fold_build2 (EQ_EXPR
, type
, inner
, comp_const
);
5061 if (op_code
== MAX_EXPR
&& (consts_equal
|| consts_lt
))
5062 /* MAX (X, 0) > 0 -> X > 0
5063 MAX (X, 0) > 5 -> X > 5 */
5064 return fold_build2 (GT_EXPR
, type
, inner
, comp_const
);
5066 else if (op_code
== MAX_EXPR
)
5067 /* MAX (X, 0) > -1 -> true */
5068 return omit_one_operand (type
, integer_one_node
, inner
);
5070 else if (op_code
== MIN_EXPR
&& (consts_equal
|| consts_lt
))
5071 /* MIN (X, 0) > 0 -> false
5072 MIN (X, 0) > 5 -> false */
5073 return omit_one_operand (type
, integer_zero_node
, inner
);
5076 /* MIN (X, 0) > -1 -> X > -1 */
5077 return fold_build2 (GT_EXPR
, type
, inner
, comp_const
);
5084 /* T is an integer expression that is being multiplied, divided, or taken a
5085 modulus (CODE says which and what kind of divide or modulus) by a
5086 constant C. See if we can eliminate that operation by folding it with
5087 other operations already in T. WIDE_TYPE, if non-null, is a type that
5088 should be used for the computation if wider than our type.
5090 For example, if we are dividing (X * 8) + (Y * 16) by 4, we can return
5091 (X * 2) + (Y * 4). We must, however, be assured that either the original
5092 expression would not overflow or that overflow is undefined for the type
5093 in the language in question.
5095 We also canonicalize (X + 7) * 4 into X * 4 + 28 in the hope that either
5096 the machine has a multiply-accumulate insn or that this is part of an
5097 addressing calculation.
5099 If we return a non-null expression, it is an equivalent form of the
5100 original computation, but need not be in the original type. */
5103 extract_muldiv (tree t
, tree c
, enum tree_code code
, tree wide_type
)
5105 /* To avoid exponential search depth, refuse to allow recursion past
5106 three levels. Beyond that (1) it's highly unlikely that we'll find
5107 something interesting and (2) we've probably processed it before
5108 when we built the inner expression. */
5117 ret
= extract_muldiv_1 (t
, c
, code
, wide_type
);
5124 extract_muldiv_1 (tree t
, tree c
, enum tree_code code
, tree wide_type
)
5126 tree type
= TREE_TYPE (t
);
5127 enum tree_code tcode
= TREE_CODE (t
);
5128 tree ctype
= (wide_type
!= 0 && (GET_MODE_SIZE (TYPE_MODE (wide_type
))
5129 > GET_MODE_SIZE (TYPE_MODE (type
)))
5130 ? wide_type
: type
);
5132 int same_p
= tcode
== code
;
5133 tree op0
= NULL_TREE
, op1
= NULL_TREE
;
5135 /* Don't deal with constants of zero here; they confuse the code below. */
5136 if (integer_zerop (c
))
5139 if (TREE_CODE_CLASS (tcode
) == tcc_unary
)
5140 op0
= TREE_OPERAND (t
, 0);
5142 if (TREE_CODE_CLASS (tcode
) == tcc_binary
)
5143 op0
= TREE_OPERAND (t
, 0), op1
= TREE_OPERAND (t
, 1);
5145 /* Note that we need not handle conditional operations here since fold
5146 already handles those cases. So just do arithmetic here. */
5150 /* For a constant, we can always simplify if we are a multiply
5151 or (for divide and modulus) if it is a multiple of our constant. */
5152 if (code
== MULT_EXPR
5153 || integer_zerop (const_binop (TRUNC_MOD_EXPR
, t
, c
, 0)))
5154 return const_binop (code
, fold_convert (ctype
, t
),
5155 fold_convert (ctype
, c
), 0);
5158 case CONVERT_EXPR
: case NON_LVALUE_EXPR
: case NOP_EXPR
:
5159 /* If op0 is an expression ... */
5160 if ((COMPARISON_CLASS_P (op0
)
5161 || UNARY_CLASS_P (op0
)
5162 || BINARY_CLASS_P (op0
)
5163 || EXPRESSION_CLASS_P (op0
))
5164 /* ... and is unsigned, and its type is smaller than ctype,
5165 then we cannot pass through as widening. */
5166 && ((TYPE_UNSIGNED (TREE_TYPE (op0
))
5167 && ! (TREE_CODE (TREE_TYPE (op0
)) == INTEGER_TYPE
5168 && TYPE_IS_SIZETYPE (TREE_TYPE (op0
)))
5169 && (GET_MODE_SIZE (TYPE_MODE (ctype
))
5170 > GET_MODE_SIZE (TYPE_MODE (TREE_TYPE (op0
)))))
5171 /* ... or this is a truncation (t is narrower than op0),
5172 then we cannot pass through this narrowing. */
5173 || (GET_MODE_SIZE (TYPE_MODE (type
))
5174 < GET_MODE_SIZE (TYPE_MODE (TREE_TYPE (op0
))))
5175 /* ... or signedness changes for division or modulus,
5176 then we cannot pass through this conversion. */
5177 || (code
!= MULT_EXPR
5178 && (TYPE_UNSIGNED (ctype
)
5179 != TYPE_UNSIGNED (TREE_TYPE (op0
))))))
5182 /* Pass the constant down and see if we can make a simplification. If
5183 we can, replace this expression with the inner simplification for
5184 possible later conversion to our or some other type. */
5185 if ((t2
= fold_convert (TREE_TYPE (op0
), c
)) != 0
5186 && TREE_CODE (t2
) == INTEGER_CST
5187 && ! TREE_CONSTANT_OVERFLOW (t2
)
5188 && (0 != (t1
= extract_muldiv (op0
, t2
, code
,
5190 ? ctype
: NULL_TREE
))))
5195 /* If widening the type changes it from signed to unsigned, then we
5196 must avoid building ABS_EXPR itself as unsigned. */
5197 if (TYPE_UNSIGNED (ctype
) && !TYPE_UNSIGNED (type
))
5199 tree cstype
= (*lang_hooks
.types
.signed_type
) (ctype
);
5200 if ((t1
= extract_muldiv (op0
, c
, code
, cstype
)) != 0)
5202 t1
= fold_build1 (tcode
, cstype
, fold_convert (cstype
, t1
));
5203 return fold_convert (ctype
, t1
);
5209 if ((t1
= extract_muldiv (op0
, c
, code
, wide_type
)) != 0)
5210 return fold_build1 (tcode
, ctype
, fold_convert (ctype
, t1
));
5213 case MIN_EXPR
: case MAX_EXPR
:
5214 /* If widening the type changes the signedness, then we can't perform
5215 this optimization as that changes the result. */
5216 if (TYPE_UNSIGNED (ctype
) != TYPE_UNSIGNED (type
))
5219 /* MIN (a, b) / 5 -> MIN (a / 5, b / 5) */
5220 if ((t1
= extract_muldiv (op0
, c
, code
, wide_type
)) != 0
5221 && (t2
= extract_muldiv (op1
, c
, code
, wide_type
)) != 0)
5223 if (tree_int_cst_sgn (c
) < 0)
5224 tcode
= (tcode
== MIN_EXPR
? MAX_EXPR
: MIN_EXPR
);
5226 return fold_build2 (tcode
, ctype
, fold_convert (ctype
, t1
),
5227 fold_convert (ctype
, t2
));
5231 case LSHIFT_EXPR
: case RSHIFT_EXPR
:
5232 /* If the second operand is constant, this is a multiplication
5233 or floor division, by a power of two, so we can treat it that
5234 way unless the multiplier or divisor overflows. Signed
5235 left-shift overflow is implementation-defined rather than
5236 undefined in C90, so do not convert signed left shift into
5238 if (TREE_CODE (op1
) == INTEGER_CST
5239 && (tcode
== RSHIFT_EXPR
|| TYPE_UNSIGNED (TREE_TYPE (op0
)))
5240 /* const_binop may not detect overflow correctly,
5241 so check for it explicitly here. */
5242 && TYPE_PRECISION (TREE_TYPE (size_one_node
)) > TREE_INT_CST_LOW (op1
)
5243 && TREE_INT_CST_HIGH (op1
) == 0
5244 && 0 != (t1
= fold_convert (ctype
,
5245 const_binop (LSHIFT_EXPR
,
5248 && ! TREE_OVERFLOW (t1
))
5249 return extract_muldiv (build2 (tcode
== LSHIFT_EXPR
5250 ? MULT_EXPR
: FLOOR_DIV_EXPR
,
5251 ctype
, fold_convert (ctype
, op0
), t1
),
5252 c
, code
, wide_type
);
5255 case PLUS_EXPR
: case MINUS_EXPR
:
5256 /* See if we can eliminate the operation on both sides. If we can, we
5257 can return a new PLUS or MINUS. If we can't, the only remaining
5258 cases where we can do anything are if the second operand is a
5260 t1
= extract_muldiv (op0
, c
, code
, wide_type
);
5261 t2
= extract_muldiv (op1
, c
, code
, wide_type
);
5262 if (t1
!= 0 && t2
!= 0
5263 && (code
== MULT_EXPR
5264 /* If not multiplication, we can only do this if both operands
5265 are divisible by c. */
5266 || (multiple_of_p (ctype
, op0
, c
)
5267 && multiple_of_p (ctype
, op1
, c
))))
5268 return fold_build2 (tcode
, ctype
, fold_convert (ctype
, t1
),
5269 fold_convert (ctype
, t2
));
5271 /* If this was a subtraction, negate OP1 and set it to be an addition.
5272 This simplifies the logic below. */
5273 if (tcode
== MINUS_EXPR
)
5274 tcode
= PLUS_EXPR
, op1
= negate_expr (op1
);
5276 if (TREE_CODE (op1
) != INTEGER_CST
)
5279 /* If either OP1 or C are negative, this optimization is not safe for
5280 some of the division and remainder types while for others we need
5281 to change the code. */
5282 if (tree_int_cst_sgn (op1
) < 0 || tree_int_cst_sgn (c
) < 0)
5284 if (code
== CEIL_DIV_EXPR
)
5285 code
= FLOOR_DIV_EXPR
;
5286 else if (code
== FLOOR_DIV_EXPR
)
5287 code
= CEIL_DIV_EXPR
;
5288 else if (code
!= MULT_EXPR
5289 && code
!= CEIL_MOD_EXPR
&& code
!= FLOOR_MOD_EXPR
)
5293 /* If it's a multiply or a division/modulus operation of a multiple
5294 of our constant, do the operation and verify it doesn't overflow. */
5295 if (code
== MULT_EXPR
5296 || integer_zerop (const_binop (TRUNC_MOD_EXPR
, op1
, c
, 0)))
5298 op1
= const_binop (code
, fold_convert (ctype
, op1
),
5299 fold_convert (ctype
, c
), 0);
5300 /* We allow the constant to overflow with wrapping semantics. */
5302 || (TREE_OVERFLOW (op1
) && ! flag_wrapv
))
5308 /* If we have an unsigned type is not a sizetype, we cannot widen
5309 the operation since it will change the result if the original
5310 computation overflowed. */
5311 if (TYPE_UNSIGNED (ctype
)
5312 && ! (TREE_CODE (ctype
) == INTEGER_TYPE
&& TYPE_IS_SIZETYPE (ctype
))
5316 /* If we were able to eliminate our operation from the first side,
5317 apply our operation to the second side and reform the PLUS. */
5318 if (t1
!= 0 && (TREE_CODE (t1
) != code
|| code
== MULT_EXPR
))
5319 return fold_build2 (tcode
, ctype
, fold_convert (ctype
, t1
), op1
);
5321 /* The last case is if we are a multiply. In that case, we can
5322 apply the distributive law to commute the multiply and addition
5323 if the multiplication of the constants doesn't overflow. */
5324 if (code
== MULT_EXPR
)
5325 return fold_build2 (tcode
, ctype
,
5326 fold_build2 (code
, ctype
,
5327 fold_convert (ctype
, op0
),
5328 fold_convert (ctype
, c
)),
5334 /* We have a special case here if we are doing something like
5335 (C * 8) % 4 since we know that's zero. */
5336 if ((code
== TRUNC_MOD_EXPR
|| code
== CEIL_MOD_EXPR
5337 || code
== FLOOR_MOD_EXPR
|| code
== ROUND_MOD_EXPR
)
5338 && TREE_CODE (TREE_OPERAND (t
, 1)) == INTEGER_CST
5339 && integer_zerop (const_binop (TRUNC_MOD_EXPR
, op1
, c
, 0)))
5340 return omit_one_operand (type
, integer_zero_node
, op0
);
5342 /* ... fall through ... */
5344 case TRUNC_DIV_EXPR
: case CEIL_DIV_EXPR
: case FLOOR_DIV_EXPR
:
5345 case ROUND_DIV_EXPR
: case EXACT_DIV_EXPR
:
5346 /* If we can extract our operation from the LHS, do so and return a
5347 new operation. Likewise for the RHS from a MULT_EXPR. Otherwise,
5348 do something only if the second operand is a constant. */
5350 && (t1
= extract_muldiv (op0
, c
, code
, wide_type
)) != 0)
5351 return fold_build2 (tcode
, ctype
, fold_convert (ctype
, t1
),
5352 fold_convert (ctype
, op1
));
5353 else if (tcode
== MULT_EXPR
&& code
== MULT_EXPR
5354 && (t1
= extract_muldiv (op1
, c
, code
, wide_type
)) != 0)
5355 return fold_build2 (tcode
, ctype
, fold_convert (ctype
, op0
),
5356 fold_convert (ctype
, t1
));
5357 else if (TREE_CODE (op1
) != INTEGER_CST
)
5360 /* If these are the same operation types, we can associate them
5361 assuming no overflow. */
5363 && 0 != (t1
= const_binop (MULT_EXPR
, fold_convert (ctype
, op1
),
5364 fold_convert (ctype
, c
), 0))
5365 && ! TREE_OVERFLOW (t1
))
5366 return fold_build2 (tcode
, ctype
, fold_convert (ctype
, op0
), t1
);
5368 /* If these operations "cancel" each other, we have the main
5369 optimizations of this pass, which occur when either constant is a
5370 multiple of the other, in which case we replace this with either an
5371 operation or CODE or TCODE.
5373 If we have an unsigned type that is not a sizetype, we cannot do
5374 this since it will change the result if the original computation
5376 if ((! TYPE_UNSIGNED (ctype
)
5377 || (TREE_CODE (ctype
) == INTEGER_TYPE
&& TYPE_IS_SIZETYPE (ctype
)))
5379 && ((code
== MULT_EXPR
&& tcode
== EXACT_DIV_EXPR
)
5380 || (tcode
== MULT_EXPR
5381 && code
!= TRUNC_MOD_EXPR
&& code
!= CEIL_MOD_EXPR
5382 && code
!= FLOOR_MOD_EXPR
&& code
!= ROUND_MOD_EXPR
)))
5384 if (integer_zerop (const_binop (TRUNC_MOD_EXPR
, op1
, c
, 0)))
5385 return fold_build2 (tcode
, ctype
, fold_convert (ctype
, op0
),
5386 fold_convert (ctype
,
5387 const_binop (TRUNC_DIV_EXPR
,
5389 else if (integer_zerop (const_binop (TRUNC_MOD_EXPR
, c
, op1
, 0)))
5390 return fold_build2 (code
, ctype
, fold_convert (ctype
, op0
),
5391 fold_convert (ctype
,
5392 const_binop (TRUNC_DIV_EXPR
,
5404 /* Return a node which has the indicated constant VALUE (either 0 or
5405 1), and is of the indicated TYPE. */
5408 constant_boolean_node (int value
, tree type
)
5410 if (type
== integer_type_node
)
5411 return value
? integer_one_node
: integer_zero_node
;
5412 else if (type
== boolean_type_node
)
5413 return value
? boolean_true_node
: boolean_false_node
;
5415 return build_int_cst (type
, value
);
5419 /* Return true if expr looks like an ARRAY_REF and set base and
5420 offset to the appropriate trees. If there is no offset,
5421 offset is set to NULL_TREE. */
5424 extract_array_ref (tree expr
, tree
*base
, tree
*offset
)
5426 /* We have to be careful with stripping nops as with the
5427 base type the meaning of the offset can change. */
5428 tree inner_expr
= expr
;
5429 STRIP_NOPS (inner_expr
);
5430 /* One canonical form is a PLUS_EXPR with the first
5431 argument being an ADDR_EXPR with a possible NOP_EXPR
5433 if (TREE_CODE (expr
) == PLUS_EXPR
)
5435 tree op0
= TREE_OPERAND (expr
, 0);
5437 if (TREE_CODE (op0
) == ADDR_EXPR
)
5439 *base
= TREE_OPERAND (expr
, 0);
5440 *offset
= TREE_OPERAND (expr
, 1);
5444 /* Other canonical form is an ADDR_EXPR of an ARRAY_REF,
5445 which we transform into an ADDR_EXPR with appropriate
5446 offset. For other arguments to the ADDR_EXPR we assume
5447 zero offset and as such do not care about the ADDR_EXPR
5448 type and strip possible nops from it. */
5449 else if (TREE_CODE (inner_expr
) == ADDR_EXPR
)
5451 tree op0
= TREE_OPERAND (inner_expr
, 0);
5452 if (TREE_CODE (op0
) == ARRAY_REF
)
5454 *base
= build_fold_addr_expr (TREE_OPERAND (op0
, 0));
5455 *offset
= TREE_OPERAND (op0
, 1);
5460 *offset
= NULL_TREE
;
5469 /* Transform `a + (b ? x : y)' into `b ? (a + x) : (a + y)'.
5470 Transform, `a + (x < y)' into `(x < y) ? (a + 1) : (a + 0)'. Here
5471 CODE corresponds to the `+', COND to the `(b ? x : y)' or `(x < y)'
5472 expression, and ARG to `a'. If COND_FIRST_P is nonzero, then the
5473 COND is the first argument to CODE; otherwise (as in the example
5474 given here), it is the second argument. TYPE is the type of the
5475 original expression. Return NULL_TREE if no simplification is
5479 fold_binary_op_with_conditional_arg (enum tree_code code
,
5480 tree type
, tree op0
, tree op1
,
5481 tree cond
, tree arg
, int cond_first_p
)
5483 tree cond_type
= cond_first_p
? TREE_TYPE (op0
) : TREE_TYPE (op1
);
5484 tree arg_type
= cond_first_p
? TREE_TYPE (op1
) : TREE_TYPE (op0
);
5485 tree test
, true_value
, false_value
;
5486 tree lhs
= NULL_TREE
;
5487 tree rhs
= NULL_TREE
;
5489 /* This transformation is only worthwhile if we don't have to wrap
5490 arg in a SAVE_EXPR, and the operation can be simplified on at least
5491 one of the branches once its pushed inside the COND_EXPR. */
5492 if (!TREE_CONSTANT (arg
))
5495 if (TREE_CODE (cond
) == COND_EXPR
)
5497 test
= TREE_OPERAND (cond
, 0);
5498 true_value
= TREE_OPERAND (cond
, 1);
5499 false_value
= TREE_OPERAND (cond
, 2);
5500 /* If this operand throws an expression, then it does not make
5501 sense to try to perform a logical or arithmetic operation
5503 if (VOID_TYPE_P (TREE_TYPE (true_value
)))
5505 if (VOID_TYPE_P (TREE_TYPE (false_value
)))
5510 tree testtype
= TREE_TYPE (cond
);
5512 true_value
= constant_boolean_node (true, testtype
);
5513 false_value
= constant_boolean_node (false, testtype
);
5516 arg
= fold_convert (arg_type
, arg
);
5519 true_value
= fold_convert (cond_type
, true_value
);
5521 lhs
= fold_build2 (code
, type
, true_value
, arg
);
5523 lhs
= fold_build2 (code
, type
, arg
, true_value
);
5527 false_value
= fold_convert (cond_type
, false_value
);
5529 rhs
= fold_build2 (code
, type
, false_value
, arg
);
5531 rhs
= fold_build2 (code
, type
, arg
, false_value
);
5534 test
= fold_build3 (COND_EXPR
, type
, test
, lhs
, rhs
);
5535 return fold_convert (type
, test
);
5539 /* Subroutine of fold() that checks for the addition of +/- 0.0.
5541 If !NEGATE, return true if ADDEND is +/-0.0 and, for all X of type
5542 TYPE, X + ADDEND is the same as X. If NEGATE, return true if X -
5543 ADDEND is the same as X.
5545 X + 0 and X - 0 both give X when X is NaN, infinite, or nonzero
5546 and finite. The problematic cases are when X is zero, and its mode
5547 has signed zeros. In the case of rounding towards -infinity,
5548 X - 0 is not the same as X because 0 - 0 is -0. In other rounding
5549 modes, X + 0 is not the same as X because -0 + 0 is 0. */
5552 fold_real_zero_addition_p (tree type
, tree addend
, int negate
)
5554 if (!real_zerop (addend
))
5557 /* Don't allow the fold with -fsignaling-nans. */
5558 if (HONOR_SNANS (TYPE_MODE (type
)))
5561 /* Allow the fold if zeros aren't signed, or their sign isn't important. */
5562 if (!HONOR_SIGNED_ZEROS (TYPE_MODE (type
)))
5565 /* Treat x + -0 as x - 0 and x - -0 as x + 0. */
5566 if (TREE_CODE (addend
) == REAL_CST
5567 && REAL_VALUE_MINUS_ZERO (TREE_REAL_CST (addend
)))
5570 /* The mode has signed zeros, and we have to honor their sign.
5571 In this situation, there is only one case we can return true for.
5572 X - 0 is the same as X unless rounding towards -infinity is
5574 return negate
&& !HONOR_SIGN_DEPENDENT_ROUNDING (TYPE_MODE (type
));
5577 /* Subroutine of fold() that checks comparisons of built-in math
5578 functions against real constants.
5580 FCODE is the DECL_FUNCTION_CODE of the built-in, CODE is the comparison
5581 operator: EQ_EXPR, NE_EXPR, GT_EXPR, LT_EXPR, GE_EXPR or LE_EXPR. TYPE
5582 is the type of the result and ARG0 and ARG1 are the operands of the
5583 comparison. ARG1 must be a TREE_REAL_CST.
5585 The function returns the constant folded tree if a simplification
5586 can be made, and NULL_TREE otherwise. */
5589 fold_mathfn_compare (enum built_in_function fcode
, enum tree_code code
,
5590 tree type
, tree arg0
, tree arg1
)
5594 if (BUILTIN_SQRT_P (fcode
))
5596 tree arg
= TREE_VALUE (TREE_OPERAND (arg0
, 1));
5597 enum machine_mode mode
= TYPE_MODE (TREE_TYPE (arg0
));
5599 c
= TREE_REAL_CST (arg1
);
5600 if (REAL_VALUE_NEGATIVE (c
))
5602 /* sqrt(x) < y is always false, if y is negative. */
5603 if (code
== EQ_EXPR
|| code
== LT_EXPR
|| code
== LE_EXPR
)
5604 return omit_one_operand (type
, integer_zero_node
, arg
);
5606 /* sqrt(x) > y is always true, if y is negative and we
5607 don't care about NaNs, i.e. negative values of x. */
5608 if (code
== NE_EXPR
|| !HONOR_NANS (mode
))
5609 return omit_one_operand (type
, integer_one_node
, arg
);
5611 /* sqrt(x) > y is the same as x >= 0, if y is negative. */
5612 return fold_build2 (GE_EXPR
, type
, arg
,
5613 build_real (TREE_TYPE (arg
), dconst0
));
5615 else if (code
== GT_EXPR
|| code
== GE_EXPR
)
5619 REAL_ARITHMETIC (c2
, MULT_EXPR
, c
, c
);
5620 real_convert (&c2
, mode
, &c2
);
5622 if (REAL_VALUE_ISINF (c2
))
5624 /* sqrt(x) > y is x == +Inf, when y is very large. */
5625 if (HONOR_INFINITIES (mode
))
5626 return fold_build2 (EQ_EXPR
, type
, arg
,
5627 build_real (TREE_TYPE (arg
), c2
));
5629 /* sqrt(x) > y is always false, when y is very large
5630 and we don't care about infinities. */
5631 return omit_one_operand (type
, integer_zero_node
, arg
);
5634 /* sqrt(x) > c is the same as x > c*c. */
5635 return fold_build2 (code
, type
, arg
,
5636 build_real (TREE_TYPE (arg
), c2
));
5638 else if (code
== LT_EXPR
|| code
== LE_EXPR
)
5642 REAL_ARITHMETIC (c2
, MULT_EXPR
, c
, c
);
5643 real_convert (&c2
, mode
, &c2
);
5645 if (REAL_VALUE_ISINF (c2
))
5647 /* sqrt(x) < y is always true, when y is a very large
5648 value and we don't care about NaNs or Infinities. */
5649 if (! HONOR_NANS (mode
) && ! HONOR_INFINITIES (mode
))
5650 return omit_one_operand (type
, integer_one_node
, arg
);
5652 /* sqrt(x) < y is x != +Inf when y is very large and we
5653 don't care about NaNs. */
5654 if (! HONOR_NANS (mode
))
5655 return fold_build2 (NE_EXPR
, type
, arg
,
5656 build_real (TREE_TYPE (arg
), c2
));
5658 /* sqrt(x) < y is x >= 0 when y is very large and we
5659 don't care about Infinities. */
5660 if (! HONOR_INFINITIES (mode
))
5661 return fold_build2 (GE_EXPR
, type
, arg
,
5662 build_real (TREE_TYPE (arg
), dconst0
));
5664 /* sqrt(x) < y is x >= 0 && x != +Inf, when y is large. */
5665 if (lang_hooks
.decls
.global_bindings_p () != 0
5666 || CONTAINS_PLACEHOLDER_P (arg
))
5669 arg
= save_expr (arg
);
5670 return fold_build2 (TRUTH_ANDIF_EXPR
, type
,
5671 fold_build2 (GE_EXPR
, type
, arg
,
5672 build_real (TREE_TYPE (arg
),
5674 fold_build2 (NE_EXPR
, type
, arg
,
5675 build_real (TREE_TYPE (arg
),
5679 /* sqrt(x) < c is the same as x < c*c, if we ignore NaNs. */
5680 if (! HONOR_NANS (mode
))
5681 return fold_build2 (code
, type
, arg
,
5682 build_real (TREE_TYPE (arg
), c2
));
5684 /* sqrt(x) < c is the same as x >= 0 && x < c*c. */
5685 if (lang_hooks
.decls
.global_bindings_p () == 0
5686 && ! CONTAINS_PLACEHOLDER_P (arg
))
5688 arg
= save_expr (arg
);
5689 return fold_build2 (TRUTH_ANDIF_EXPR
, type
,
5690 fold_build2 (GE_EXPR
, type
, arg
,
5691 build_real (TREE_TYPE (arg
),
5693 fold_build2 (code
, type
, arg
,
5694 build_real (TREE_TYPE (arg
),
5703 /* Subroutine of fold() that optimizes comparisons against Infinities,
5704 either +Inf or -Inf.
5706 CODE is the comparison operator: EQ_EXPR, NE_EXPR, GT_EXPR, LT_EXPR,
5707 GE_EXPR or LE_EXPR. TYPE is the type of the result and ARG0 and ARG1
5708 are the operands of the comparison. ARG1 must be a TREE_REAL_CST.
5710 The function returns the constant folded tree if a simplification
5711 can be made, and NULL_TREE otherwise. */
5714 fold_inf_compare (enum tree_code code
, tree type
, tree arg0
, tree arg1
)
5716 enum machine_mode mode
;
5717 REAL_VALUE_TYPE max
;
5721 mode
= TYPE_MODE (TREE_TYPE (arg0
));
5723 /* For negative infinity swap the sense of the comparison. */
5724 neg
= REAL_VALUE_NEGATIVE (TREE_REAL_CST (arg1
));
5726 code
= swap_tree_comparison (code
);
5731 /* x > +Inf is always false, if with ignore sNANs. */
5732 if (HONOR_SNANS (mode
))
5734 return omit_one_operand (type
, integer_zero_node
, arg0
);
5737 /* x <= +Inf is always true, if we don't case about NaNs. */
5738 if (! HONOR_NANS (mode
))
5739 return omit_one_operand (type
, integer_one_node
, arg0
);
5741 /* x <= +Inf is the same as x == x, i.e. isfinite(x). */
5742 if (lang_hooks
.decls
.global_bindings_p () == 0
5743 && ! CONTAINS_PLACEHOLDER_P (arg0
))
5745 arg0
= save_expr (arg0
);
5746 return fold_build2 (EQ_EXPR
, type
, arg0
, arg0
);
5752 /* x == +Inf and x >= +Inf are always equal to x > DBL_MAX. */
5753 real_maxval (&max
, neg
, mode
);
5754 return fold_build2 (neg
? LT_EXPR
: GT_EXPR
, type
,
5755 arg0
, build_real (TREE_TYPE (arg0
), max
));
5758 /* x < +Inf is always equal to x <= DBL_MAX. */
5759 real_maxval (&max
, neg
, mode
);
5760 return fold_build2 (neg
? GE_EXPR
: LE_EXPR
, type
,
5761 arg0
, build_real (TREE_TYPE (arg0
), max
));
5764 /* x != +Inf is always equal to !(x > DBL_MAX). */
5765 real_maxval (&max
, neg
, mode
);
5766 if (! HONOR_NANS (mode
))
5767 return fold_build2 (neg
? GE_EXPR
: LE_EXPR
, type
,
5768 arg0
, build_real (TREE_TYPE (arg0
), max
));
5770 /* The transformation below creates non-gimple code and thus is
5771 not appropriate if we are in gimple form. */
5775 temp
= fold_build2 (neg
? LT_EXPR
: GT_EXPR
, type
,
5776 arg0
, build_real (TREE_TYPE (arg0
), max
));
5777 return fold_build1 (TRUTH_NOT_EXPR
, type
, temp
);
5786 /* Subroutine of fold() that optimizes comparisons of a division by
5787 a nonzero integer constant against an integer constant, i.e.
5790 CODE is the comparison operator: EQ_EXPR, NE_EXPR, GT_EXPR, LT_EXPR,
5791 GE_EXPR or LE_EXPR. TYPE is the type of the result and ARG0 and ARG1
5792 are the operands of the comparison. ARG1 must be a TREE_REAL_CST.
5794 The function returns the constant folded tree if a simplification
5795 can be made, and NULL_TREE otherwise. */
5798 fold_div_compare (enum tree_code code
, tree type
, tree arg0
, tree arg1
)
5800 tree prod
, tmp
, hi
, lo
;
5801 tree arg00
= TREE_OPERAND (arg0
, 0);
5802 tree arg01
= TREE_OPERAND (arg0
, 1);
5803 unsigned HOST_WIDE_INT lpart
;
5804 HOST_WIDE_INT hpart
;
5807 /* We have to do this the hard way to detect unsigned overflow.
5808 prod = int_const_binop (MULT_EXPR, arg01, arg1, 0); */
5809 overflow
= mul_double (TREE_INT_CST_LOW (arg01
),
5810 TREE_INT_CST_HIGH (arg01
),
5811 TREE_INT_CST_LOW (arg1
),
5812 TREE_INT_CST_HIGH (arg1
), &lpart
, &hpart
);
5813 prod
= build_int_cst_wide (TREE_TYPE (arg00
), lpart
, hpart
);
5814 prod
= force_fit_type (prod
, -1, overflow
, false);
5816 if (TYPE_UNSIGNED (TREE_TYPE (arg0
)))
5818 tmp
= int_const_binop (MINUS_EXPR
, arg01
, integer_one_node
, 0);
5821 /* Likewise hi = int_const_binop (PLUS_EXPR, prod, tmp, 0). */
5822 overflow
= add_double (TREE_INT_CST_LOW (prod
),
5823 TREE_INT_CST_HIGH (prod
),
5824 TREE_INT_CST_LOW (tmp
),
5825 TREE_INT_CST_HIGH (tmp
),
5827 hi
= build_int_cst_wide (TREE_TYPE (arg00
), lpart
, hpart
);
5828 hi
= force_fit_type (hi
, -1, overflow
| TREE_OVERFLOW (prod
),
5829 TREE_CONSTANT_OVERFLOW (prod
));
5831 else if (tree_int_cst_sgn (arg01
) >= 0)
5833 tmp
= int_const_binop (MINUS_EXPR
, arg01
, integer_one_node
, 0);
5834 switch (tree_int_cst_sgn (arg1
))
5837 lo
= int_const_binop (MINUS_EXPR
, prod
, tmp
, 0);
5842 lo
= fold_negate_const (tmp
, TREE_TYPE (arg0
));
5847 hi
= int_const_binop (PLUS_EXPR
, prod
, tmp
, 0);
5857 /* A negative divisor reverses the relational operators. */
5858 code
= swap_tree_comparison (code
);
5860 tmp
= int_const_binop (PLUS_EXPR
, arg01
, integer_one_node
, 0);
5861 switch (tree_int_cst_sgn (arg1
))
5864 hi
= int_const_binop (MINUS_EXPR
, prod
, tmp
, 0);
5869 hi
= fold_negate_const (tmp
, TREE_TYPE (arg0
));
5874 lo
= int_const_binop (PLUS_EXPR
, prod
, tmp
, 0);
5886 if (TREE_OVERFLOW (lo
) && TREE_OVERFLOW (hi
))
5887 return omit_one_operand (type
, integer_zero_node
, arg00
);
5888 if (TREE_OVERFLOW (hi
))
5889 return fold_build2 (GE_EXPR
, type
, arg00
, lo
);
5890 if (TREE_OVERFLOW (lo
))
5891 return fold_build2 (LE_EXPR
, type
, arg00
, hi
);
5892 return build_range_check (type
, arg00
, 1, lo
, hi
);
5895 if (TREE_OVERFLOW (lo
) && TREE_OVERFLOW (hi
))
5896 return omit_one_operand (type
, integer_one_node
, arg00
);
5897 if (TREE_OVERFLOW (hi
))
5898 return fold_build2 (LT_EXPR
, type
, arg00
, lo
);
5899 if (TREE_OVERFLOW (lo
))
5900 return fold_build2 (GT_EXPR
, type
, arg00
, hi
);
5901 return build_range_check (type
, arg00
, 0, lo
, hi
);
5904 if (TREE_OVERFLOW (lo
))
5905 return omit_one_operand (type
, integer_zero_node
, arg00
);
5906 return fold_build2 (LT_EXPR
, type
, arg00
, lo
);
5909 if (TREE_OVERFLOW (hi
))
5910 return omit_one_operand (type
, integer_one_node
, arg00
);
5911 return fold_build2 (LE_EXPR
, type
, arg00
, hi
);
5914 if (TREE_OVERFLOW (hi
))
5915 return omit_one_operand (type
, integer_zero_node
, arg00
);
5916 return fold_build2 (GT_EXPR
, type
, arg00
, hi
);
5919 if (TREE_OVERFLOW (lo
))
5920 return omit_one_operand (type
, integer_one_node
, arg00
);
5921 return fold_build2 (GE_EXPR
, type
, arg00
, lo
);
5931 /* If CODE with arguments ARG0 and ARG1 represents a single bit
5932 equality/inequality test, then return a simplified form of the test
5933 using a sign testing. Otherwise return NULL. TYPE is the desired
5937 fold_single_bit_test_into_sign_test (enum tree_code code
, tree arg0
, tree arg1
,
5940 /* If this is testing a single bit, we can optimize the test. */
5941 if ((code
== NE_EXPR
|| code
== EQ_EXPR
)
5942 && TREE_CODE (arg0
) == BIT_AND_EXPR
&& integer_zerop (arg1
)
5943 && integer_pow2p (TREE_OPERAND (arg0
, 1)))
5945 /* If we have (A & C) != 0 where C is the sign bit of A, convert
5946 this into A < 0. Similarly for (A & C) == 0 into A >= 0. */
5947 tree arg00
= sign_bit_p (TREE_OPERAND (arg0
, 0), TREE_OPERAND (arg0
, 1));
5949 if (arg00
!= NULL_TREE
5950 /* This is only a win if casting to a signed type is cheap,
5951 i.e. when arg00's type is not a partial mode. */
5952 && TYPE_PRECISION (TREE_TYPE (arg00
))
5953 == GET_MODE_BITSIZE (TYPE_MODE (TREE_TYPE (arg00
))))
5955 tree stype
= lang_hooks
.types
.signed_type (TREE_TYPE (arg00
));
5956 return fold_build2 (code
== EQ_EXPR
? GE_EXPR
: LT_EXPR
,
5957 result_type
, fold_convert (stype
, arg00
),
5958 fold_convert (stype
, integer_zero_node
));
5965 /* If CODE with arguments ARG0 and ARG1 represents a single bit
5966 equality/inequality test, then return a simplified form of
5967 the test using shifts and logical operations. Otherwise return
5968 NULL. TYPE is the desired result type. */
5971 fold_single_bit_test (enum tree_code code
, tree arg0
, tree arg1
,
5974 /* If this is testing a single bit, we can optimize the test. */
5975 if ((code
== NE_EXPR
|| code
== EQ_EXPR
)
5976 && TREE_CODE (arg0
) == BIT_AND_EXPR
&& integer_zerop (arg1
)
5977 && integer_pow2p (TREE_OPERAND (arg0
, 1)))
5979 tree inner
= TREE_OPERAND (arg0
, 0);
5980 tree type
= TREE_TYPE (arg0
);
5981 int bitnum
= tree_log2 (TREE_OPERAND (arg0
, 1));
5982 enum machine_mode operand_mode
= TYPE_MODE (type
);
5984 tree signed_type
, unsigned_type
, intermediate_type
;
5987 /* First, see if we can fold the single bit test into a sign-bit
5989 tem
= fold_single_bit_test_into_sign_test (code
, arg0
, arg1
,
5994 /* Otherwise we have (A & C) != 0 where C is a single bit,
5995 convert that into ((A >> C2) & 1). Where C2 = log2(C).
5996 Similarly for (A & C) == 0. */
5998 /* If INNER is a right shift of a constant and it plus BITNUM does
5999 not overflow, adjust BITNUM and INNER. */
6000 if (TREE_CODE (inner
) == RSHIFT_EXPR
6001 && TREE_CODE (TREE_OPERAND (inner
, 1)) == INTEGER_CST
6002 && TREE_INT_CST_HIGH (TREE_OPERAND (inner
, 1)) == 0
6003 && bitnum
< TYPE_PRECISION (type
)
6004 && 0 > compare_tree_int (TREE_OPERAND (inner
, 1),
6005 bitnum
- TYPE_PRECISION (type
)))
6007 bitnum
+= TREE_INT_CST_LOW (TREE_OPERAND (inner
, 1));
6008 inner
= TREE_OPERAND (inner
, 0);
6011 /* If we are going to be able to omit the AND below, we must do our
6012 operations as unsigned. If we must use the AND, we have a choice.
6013 Normally unsigned is faster, but for some machines signed is. */
6014 #ifdef LOAD_EXTEND_OP
6015 ops_unsigned
= (LOAD_EXTEND_OP (operand_mode
) == SIGN_EXTEND
6016 && !flag_syntax_only
) ? 0 : 1;
6021 signed_type
= lang_hooks
.types
.type_for_mode (operand_mode
, 0);
6022 unsigned_type
= lang_hooks
.types
.type_for_mode (operand_mode
, 1);
6023 intermediate_type
= ops_unsigned
? unsigned_type
: signed_type
;
6024 inner
= fold_convert (intermediate_type
, inner
);
6027 inner
= build2 (RSHIFT_EXPR
, intermediate_type
,
6028 inner
, size_int (bitnum
));
6030 if (code
== EQ_EXPR
)
6031 inner
= fold_build2 (BIT_XOR_EXPR
, intermediate_type
,
6032 inner
, integer_one_node
);
6034 /* Put the AND last so it can combine with more things. */
6035 inner
= build2 (BIT_AND_EXPR
, intermediate_type
,
6036 inner
, integer_one_node
);
6038 /* Make sure to return the proper type. */
6039 inner
= fold_convert (result_type
, inner
);
6046 /* Check whether we are allowed to reorder operands arg0 and arg1,
6047 such that the evaluation of arg1 occurs before arg0. */
6050 reorder_operands_p (tree arg0
, tree arg1
)
6052 if (! flag_evaluation_order
)
6054 if (TREE_CONSTANT (arg0
) || TREE_CONSTANT (arg1
))
6056 return ! TREE_SIDE_EFFECTS (arg0
)
6057 && ! TREE_SIDE_EFFECTS (arg1
);
6060 /* Test whether it is preferable two swap two operands, ARG0 and
6061 ARG1, for example because ARG0 is an integer constant and ARG1
6062 isn't. If REORDER is true, only recommend swapping if we can
6063 evaluate the operands in reverse order. */
6066 tree_swap_operands_p (tree arg0
, tree arg1
, bool reorder
)
6068 STRIP_SIGN_NOPS (arg0
);
6069 STRIP_SIGN_NOPS (arg1
);
6071 if (TREE_CODE (arg1
) == INTEGER_CST
)
6073 if (TREE_CODE (arg0
) == INTEGER_CST
)
6076 if (TREE_CODE (arg1
) == REAL_CST
)
6078 if (TREE_CODE (arg0
) == REAL_CST
)
6081 if (TREE_CODE (arg1
) == COMPLEX_CST
)
6083 if (TREE_CODE (arg0
) == COMPLEX_CST
)
6086 if (TREE_CONSTANT (arg1
))
6088 if (TREE_CONSTANT (arg0
))
6094 if (reorder
&& flag_evaluation_order
6095 && (TREE_SIDE_EFFECTS (arg0
) || TREE_SIDE_EFFECTS (arg1
)))
6103 /* It is preferable to swap two SSA_NAME to ensure a canonical form
6104 for commutative and comparison operators. Ensuring a canonical
6105 form allows the optimizers to find additional redundancies without
6106 having to explicitly check for both orderings. */
6107 if (TREE_CODE (arg0
) == SSA_NAME
6108 && TREE_CODE (arg1
) == SSA_NAME
6109 && SSA_NAME_VERSION (arg0
) > SSA_NAME_VERSION (arg1
))
6115 /* Fold comparison ARG0 CODE ARG1 (with result in TYPE), where
6116 ARG0 is extended to a wider type. */
6119 fold_widened_comparison (enum tree_code code
, tree type
, tree arg0
, tree arg1
)
6121 tree arg0_unw
= get_unwidened (arg0
, NULL_TREE
);
6123 tree shorter_type
, outer_type
;
6127 if (arg0_unw
== arg0
)
6129 shorter_type
= TREE_TYPE (arg0_unw
);
6131 #ifdef HAVE_canonicalize_funcptr_for_compare
6132 /* Disable this optimization if we're casting a function pointer
6133 type on targets that require function pointer canonicalization. */
6134 if (HAVE_canonicalize_funcptr_for_compare
6135 && TREE_CODE (shorter_type
) == POINTER_TYPE
6136 && TREE_CODE (TREE_TYPE (shorter_type
)) == FUNCTION_TYPE
)
6140 if (TYPE_PRECISION (TREE_TYPE (arg0
)) <= TYPE_PRECISION (shorter_type
))
6143 arg1_unw
= get_unwidened (arg1
, shorter_type
);
6147 /* If possible, express the comparison in the shorter mode. */
6148 if ((code
== EQ_EXPR
|| code
== NE_EXPR
6149 || TYPE_UNSIGNED (TREE_TYPE (arg0
)) == TYPE_UNSIGNED (shorter_type
))
6150 && (TREE_TYPE (arg1_unw
) == shorter_type
6151 || (TREE_CODE (arg1_unw
) == INTEGER_CST
6152 && (TREE_CODE (shorter_type
) == INTEGER_TYPE
6153 || TREE_CODE (shorter_type
) == BOOLEAN_TYPE
)
6154 && int_fits_type_p (arg1_unw
, shorter_type
))))
6155 return fold_build2 (code
, type
, arg0_unw
,
6156 fold_convert (shorter_type
, arg1_unw
));
6158 if (TREE_CODE (arg1_unw
) != INTEGER_CST
)
6161 /* If we are comparing with the integer that does not fit into the range
6162 of the shorter type, the result is known. */
6163 outer_type
= TREE_TYPE (arg1_unw
);
6164 min
= lower_bound_in_type (outer_type
, shorter_type
);
6165 max
= upper_bound_in_type (outer_type
, shorter_type
);
6167 above
= integer_nonzerop (fold_relational_const (LT_EXPR
, type
,
6169 below
= integer_nonzerop (fold_relational_const (LT_EXPR
, type
,
6176 return omit_one_operand (type
, integer_zero_node
, arg0
);
6181 return omit_one_operand (type
, integer_one_node
, arg0
);
6187 return omit_one_operand (type
, integer_one_node
, arg0
);
6189 return omit_one_operand (type
, integer_zero_node
, arg0
);
6194 return omit_one_operand (type
, integer_zero_node
, arg0
);
6196 return omit_one_operand (type
, integer_one_node
, arg0
);
6205 /* Fold comparison ARG0 CODE ARG1 (with result in TYPE), where for
6206 ARG0 just the signedness is changed. */
6209 fold_sign_changed_comparison (enum tree_code code
, tree type
,
6210 tree arg0
, tree arg1
)
6212 tree arg0_inner
, tmp
;
6213 tree inner_type
, outer_type
;
6215 if (TREE_CODE (arg0
) != NOP_EXPR
6216 && TREE_CODE (arg0
) != CONVERT_EXPR
)
6219 outer_type
= TREE_TYPE (arg0
);
6220 arg0_inner
= TREE_OPERAND (arg0
, 0);
6221 inner_type
= TREE_TYPE (arg0_inner
);
6223 #ifdef HAVE_canonicalize_funcptr_for_compare
6224 /* Disable this optimization if we're casting a function pointer
6225 type on targets that require function pointer canonicalization. */
6226 if (HAVE_canonicalize_funcptr_for_compare
6227 && TREE_CODE (inner_type
) == POINTER_TYPE
6228 && TREE_CODE (TREE_TYPE (inner_type
)) == FUNCTION_TYPE
)
6232 if (TYPE_PRECISION (inner_type
) != TYPE_PRECISION (outer_type
))
6235 if (TREE_CODE (arg1
) != INTEGER_CST
6236 && !((TREE_CODE (arg1
) == NOP_EXPR
6237 || TREE_CODE (arg1
) == CONVERT_EXPR
)
6238 && TREE_TYPE (TREE_OPERAND (arg1
, 0)) == inner_type
))
6241 if (TYPE_UNSIGNED (inner_type
) != TYPE_UNSIGNED (outer_type
)
6246 if (TREE_CODE (arg1
) == INTEGER_CST
)
6248 tmp
= build_int_cst_wide (inner_type
,
6249 TREE_INT_CST_LOW (arg1
),
6250 TREE_INT_CST_HIGH (arg1
));
6251 arg1
= force_fit_type (tmp
, 0,
6252 TREE_OVERFLOW (arg1
),
6253 TREE_CONSTANT_OVERFLOW (arg1
));
6256 arg1
= fold_convert (inner_type
, arg1
);
6258 return fold_build2 (code
, type
, arg0_inner
, arg1
);
6261 /* Tries to replace &a[idx] CODE s * delta with &a[idx CODE delta], if s is
6262 step of the array. ADDR is the address. MULT is the multiplicative expression.
6263 If the function succeeds, the new address expression is returned. Otherwise
6264 NULL_TREE is returned. */
6267 try_move_mult_to_index (enum tree_code code
, tree addr
, tree mult
)
6269 tree s
, delta
, step
;
6270 tree arg0
= TREE_OPERAND (mult
, 0), arg1
= TREE_OPERAND (mult
, 1);
6271 tree ref
= TREE_OPERAND (addr
, 0), pref
;
6278 if (TREE_CODE (arg0
) == INTEGER_CST
)
6283 else if (TREE_CODE (arg1
) == INTEGER_CST
)
6291 for (;; ref
= TREE_OPERAND (ref
, 0))
6293 if (TREE_CODE (ref
) == ARRAY_REF
)
6295 step
= array_ref_element_size (ref
);
6297 if (TREE_CODE (step
) != INTEGER_CST
)
6300 itype
= TREE_TYPE (step
);
6302 /* If the type sizes do not match, we might run into problems
6303 when one of them would overflow. */
6304 if (TYPE_PRECISION (itype
) != TYPE_PRECISION (TREE_TYPE (s
)))
6307 if (!operand_equal_p (step
, fold_convert (itype
, s
), 0))
6310 delta
= fold_convert (itype
, delta
);
6314 if (!handled_component_p (ref
))
6318 /* We found the suitable array reference. So copy everything up to it,
6319 and replace the index. */
6321 pref
= TREE_OPERAND (addr
, 0);
6322 ret
= copy_node (pref
);
6327 pref
= TREE_OPERAND (pref
, 0);
6328 TREE_OPERAND (pos
, 0) = copy_node (pref
);
6329 pos
= TREE_OPERAND (pos
, 0);
6332 TREE_OPERAND (pos
, 1) = fold_build2 (code
, itype
,
6333 TREE_OPERAND (pos
, 1),
6336 return build1 (ADDR_EXPR
, TREE_TYPE (addr
), ret
);
6340 /* Fold A < X && A + 1 > Y to A < X && A >= Y. Normally A + 1 > Y
6341 means A >= Y && A != MAX, but in this case we know that
6342 A < X <= MAX. INEQ is A + 1 > Y, BOUND is A < X. */
6345 fold_to_nonsharp_ineq_using_bound (tree ineq
, tree bound
)
6347 tree a
, typea
, type
= TREE_TYPE (ineq
), a1
, diff
, y
;
6349 if (TREE_CODE (bound
) == LT_EXPR
)
6350 a
= TREE_OPERAND (bound
, 0);
6351 else if (TREE_CODE (bound
) == GT_EXPR
)
6352 a
= TREE_OPERAND (bound
, 1);
6356 typea
= TREE_TYPE (a
);
6357 if (!INTEGRAL_TYPE_P (typea
)
6358 && !POINTER_TYPE_P (typea
))
6361 if (TREE_CODE (ineq
) == LT_EXPR
)
6363 a1
= TREE_OPERAND (ineq
, 1);
6364 y
= TREE_OPERAND (ineq
, 0);
6366 else if (TREE_CODE (ineq
) == GT_EXPR
)
6368 a1
= TREE_OPERAND (ineq
, 0);
6369 y
= TREE_OPERAND (ineq
, 1);
6374 if (TREE_TYPE (a1
) != typea
)
6377 diff
= fold_build2 (MINUS_EXPR
, typea
, a1
, a
);
6378 if (!integer_onep (diff
))
6381 return fold_build2 (GE_EXPR
, type
, a
, y
);
6384 /* Fold complex addition when both components are accessible by parts.
6385 Return non-null if successful. CODE should be PLUS_EXPR for addition,
6386 or MINUS_EXPR for subtraction. */
6389 fold_complex_add (tree type
, tree ac
, tree bc
, enum tree_code code
)
6391 tree ar
, ai
, br
, bi
, rr
, ri
, inner_type
;
6393 if (TREE_CODE (ac
) == COMPLEX_EXPR
)
6394 ar
= TREE_OPERAND (ac
, 0), ai
= TREE_OPERAND (ac
, 1);
6395 else if (TREE_CODE (ac
) == COMPLEX_CST
)
6396 ar
= TREE_REALPART (ac
), ai
= TREE_IMAGPART (ac
);
6400 if (TREE_CODE (bc
) == COMPLEX_EXPR
)
6401 br
= TREE_OPERAND (bc
, 0), bi
= TREE_OPERAND (bc
, 1);
6402 else if (TREE_CODE (bc
) == COMPLEX_CST
)
6403 br
= TREE_REALPART (bc
), bi
= TREE_IMAGPART (bc
);
6407 inner_type
= TREE_TYPE (type
);
6409 rr
= fold_build2 (code
, inner_type
, ar
, br
);
6410 ri
= fold_build2 (code
, inner_type
, ai
, bi
);
6412 return fold_build2 (COMPLEX_EXPR
, type
, rr
, ri
);
6415 /* Perform some simplifications of complex multiplication when one or more
6416 of the components are constants or zeros. Return non-null if successful. */
6419 fold_complex_mult_parts (tree type
, tree ar
, tree ai
, tree br
, tree bi
)
6421 tree rr
, ri
, inner_type
, zero
;
6422 bool ar0
, ai0
, br0
, bi0
, bi1
;
6424 inner_type
= TREE_TYPE (type
);
6427 if (SCALAR_FLOAT_TYPE_P (inner_type
))
6429 ar0
= ai0
= br0
= bi0
= bi1
= false;
6431 /* We're only interested in +0.0 here, thus we don't use real_zerop. */
6433 if (TREE_CODE (ar
) == REAL_CST
6434 && REAL_VALUES_IDENTICAL (TREE_REAL_CST (ar
), dconst0
))
6435 ar0
= true, zero
= ar
;
6437 if (TREE_CODE (ai
) == REAL_CST
6438 && REAL_VALUES_IDENTICAL (TREE_REAL_CST (ai
), dconst0
))
6439 ai0
= true, zero
= ai
;
6441 if (TREE_CODE (br
) == REAL_CST
6442 && REAL_VALUES_IDENTICAL (TREE_REAL_CST (br
), dconst0
))
6443 br0
= true, zero
= br
;
6445 if (TREE_CODE (bi
) == REAL_CST
)
6447 if (REAL_VALUES_IDENTICAL (TREE_REAL_CST (bi
), dconst0
))
6448 bi0
= true, zero
= bi
;
6449 else if (REAL_VALUES_IDENTICAL (TREE_REAL_CST (bi
), dconst1
))
6455 ar0
= integer_zerop (ar
);
6458 ai0
= integer_zerop (ai
);
6461 br0
= integer_zerop (br
);
6464 bi0
= integer_zerop (bi
);
6471 bi1
= integer_onep (bi
);
6474 /* We won't optimize anything below unless something is zero. */
6478 if (ai0
&& br0
&& bi1
)
6483 else if (ai0
&& bi0
)
6485 rr
= fold_build2 (MULT_EXPR
, inner_type
, ar
, br
);
6488 else if (ai0
&& br0
)
6491 ri
= fold_build2 (MULT_EXPR
, inner_type
, ar
, bi
);
6493 else if (ar0
&& bi0
)
6496 ri
= fold_build2 (MULT_EXPR
, inner_type
, ai
, br
);
6498 else if (ar0
&& br0
)
6500 rr
= fold_build2 (MULT_EXPR
, inner_type
, ai
, bi
);
6501 rr
= fold_build1 (NEGATE_EXPR
, inner_type
, rr
);
6506 rr
= fold_build2 (MULT_EXPR
, inner_type
, ar
, br
);
6507 ri
= fold_build2 (MULT_EXPR
, inner_type
, ai
, br
);
6511 rr
= fold_build2 (MULT_EXPR
, inner_type
, ar
, br
);
6512 ri
= fold_build2 (MULT_EXPR
, inner_type
, ar
, bi
);
6516 rr
= fold_build2 (MULT_EXPR
, inner_type
, ai
, bi
);
6517 rr
= fold_build1 (NEGATE_EXPR
, inner_type
, rr
);
6518 ri
= fold_build2 (MULT_EXPR
, inner_type
, ar
, bi
);
6522 rr
= fold_build2 (MULT_EXPR
, inner_type
, ai
, bi
);
6523 rr
= fold_build1 (NEGATE_EXPR
, inner_type
, rr
);
6524 ri
= fold_build2 (MULT_EXPR
, inner_type
, ai
, br
);
6529 return fold_build2 (COMPLEX_EXPR
, type
, rr
, ri
);
6533 fold_complex_mult (tree type
, tree ac
, tree bc
)
6535 tree ar
, ai
, br
, bi
;
6537 if (TREE_CODE (ac
) == COMPLEX_EXPR
)
6538 ar
= TREE_OPERAND (ac
, 0), ai
= TREE_OPERAND (ac
, 1);
6539 else if (TREE_CODE (ac
) == COMPLEX_CST
)
6540 ar
= TREE_REALPART (ac
), ai
= TREE_IMAGPART (ac
);
6544 if (TREE_CODE (bc
) == COMPLEX_EXPR
)
6545 br
= TREE_OPERAND (bc
, 0), bi
= TREE_OPERAND (bc
, 1);
6546 else if (TREE_CODE (bc
) == COMPLEX_CST
)
6547 br
= TREE_REALPART (bc
), bi
= TREE_IMAGPART (bc
);
6551 return fold_complex_mult_parts (type
, ar
, ai
, br
, bi
);
6554 /* Perform some simplifications of complex division when one or more of
6555 the components are constants or zeros. Return non-null if successful. */
6558 fold_complex_div_parts (tree type
, tree ar
, tree ai
, tree br
, tree bi
,
6559 enum tree_code code
)
6561 tree rr
, ri
, inner_type
, zero
;
6562 bool ar0
, ai0
, br0
, bi0
, bi1
;
6564 inner_type
= TREE_TYPE (type
);
6567 if (SCALAR_FLOAT_TYPE_P (inner_type
))
6569 ar0
= ai0
= br0
= bi0
= bi1
= false;
6571 /* We're only interested in +0.0 here, thus we don't use real_zerop. */
6573 if (TREE_CODE (ar
) == REAL_CST
6574 && REAL_VALUES_IDENTICAL (TREE_REAL_CST (ar
), dconst0
))
6575 ar0
= true, zero
= ar
;
6577 if (TREE_CODE (ai
) == REAL_CST
6578 && REAL_VALUES_IDENTICAL (TREE_REAL_CST (ai
), dconst0
))
6579 ai0
= true, zero
= ai
;
6581 if (TREE_CODE (br
) == REAL_CST
6582 && REAL_VALUES_IDENTICAL (TREE_REAL_CST (br
), dconst0
))
6583 br0
= true, zero
= br
;
6585 if (TREE_CODE (bi
) == REAL_CST
)
6587 if (REAL_VALUES_IDENTICAL (TREE_REAL_CST (bi
), dconst0
))
6588 bi0
= true, zero
= bi
;
6589 else if (REAL_VALUES_IDENTICAL (TREE_REAL_CST (bi
), dconst1
))
6595 ar0
= integer_zerop (ar
);
6598 ai0
= integer_zerop (ai
);
6601 br0
= integer_zerop (br
);
6604 bi0
= integer_zerop (bi
);
6611 bi1
= integer_onep (bi
);
6614 /* We won't optimize anything below unless something is zero. */
6620 rr
= fold_build2 (code
, inner_type
, ar
, br
);
6623 else if (ai0
&& br0
)
6626 ri
= fold_build2 (code
, inner_type
, ar
, bi
);
6627 ri
= fold_build1 (NEGATE_EXPR
, inner_type
, ri
);
6629 else if (ar0
&& bi0
)
6632 ri
= fold_build2 (code
, inner_type
, ai
, br
);
6634 else if (ar0
&& br0
)
6636 rr
= fold_build2 (code
, inner_type
, ai
, bi
);
6641 rr
= fold_build2 (code
, inner_type
, ar
, br
);
6642 ri
= fold_build2 (code
, inner_type
, ai
, br
);
6646 rr
= fold_build2 (code
, inner_type
, ai
, bi
);
6647 ri
= fold_build2 (code
, inner_type
, ar
, bi
);
6648 ri
= fold_build1 (NEGATE_EXPR
, inner_type
, ri
);
6653 return fold_build2 (COMPLEX_EXPR
, type
, rr
, ri
);
6657 fold_complex_div (tree type
, tree ac
, tree bc
, enum tree_code code
)
6659 tree ar
, ai
, br
, bi
;
6661 if (TREE_CODE (ac
) == COMPLEX_EXPR
)
6662 ar
= TREE_OPERAND (ac
, 0), ai
= TREE_OPERAND (ac
, 1);
6663 else if (TREE_CODE (ac
) == COMPLEX_CST
)
6664 ar
= TREE_REALPART (ac
), ai
= TREE_IMAGPART (ac
);
6668 if (TREE_CODE (bc
) == COMPLEX_EXPR
)
6669 br
= TREE_OPERAND (bc
, 0), bi
= TREE_OPERAND (bc
, 1);
6670 else if (TREE_CODE (bc
) == COMPLEX_CST
)
6671 br
= TREE_REALPART (bc
), bi
= TREE_IMAGPART (bc
);
6675 return fold_complex_div_parts (type
, ar
, ai
, br
, bi
, code
);
6678 /* Fold a unary expression of code CODE and type TYPE with operand
6679 OP0. Return the folded expression if folding is successful.
6680 Otherwise, return NULL_TREE. */
6683 fold_unary (enum tree_code code
, tree type
, tree op0
)
6687 enum tree_code_class kind
= TREE_CODE_CLASS (code
);
6689 gcc_assert (IS_EXPR_CODE_CLASS (kind
)
6690 && TREE_CODE_LENGTH (code
) == 1);
6695 if (code
== NOP_EXPR
|| code
== FLOAT_EXPR
|| code
== CONVERT_EXPR
)
6697 /* Don't use STRIP_NOPS, because signedness of argument type matters. */
6698 STRIP_SIGN_NOPS (arg0
);
6702 /* Strip any conversions that don't change the mode. This
6703 is safe for every expression, except for a comparison
6704 expression because its signedness is derived from its
6707 Note that this is done as an internal manipulation within
6708 the constant folder, in order to find the simplest
6709 representation of the arguments so that their form can be
6710 studied. In any cases, the appropriate type conversions
6711 should be put back in the tree that will get out of the
6717 if (TREE_CODE_CLASS (code
) == tcc_unary
)
6719 if (TREE_CODE (arg0
) == COMPOUND_EXPR
)
6720 return build2 (COMPOUND_EXPR
, type
, TREE_OPERAND (arg0
, 0),
6721 fold_build1 (code
, type
, TREE_OPERAND (arg0
, 1)));
6722 else if (TREE_CODE (arg0
) == COND_EXPR
)
6724 tree arg01
= TREE_OPERAND (arg0
, 1);
6725 tree arg02
= TREE_OPERAND (arg0
, 2);
6726 if (! VOID_TYPE_P (TREE_TYPE (arg01
)))
6727 arg01
= fold_build1 (code
, type
, arg01
);
6728 if (! VOID_TYPE_P (TREE_TYPE (arg02
)))
6729 arg02
= fold_build1 (code
, type
, arg02
);
6730 tem
= fold_build3 (COND_EXPR
, type
, TREE_OPERAND (arg0
, 0),
6733 /* If this was a conversion, and all we did was to move into
6734 inside the COND_EXPR, bring it back out. But leave it if
6735 it is a conversion from integer to integer and the
6736 result precision is no wider than a word since such a
6737 conversion is cheap and may be optimized away by combine,
6738 while it couldn't if it were outside the COND_EXPR. Then return
6739 so we don't get into an infinite recursion loop taking the
6740 conversion out and then back in. */
6742 if ((code
== NOP_EXPR
|| code
== CONVERT_EXPR
6743 || code
== NON_LVALUE_EXPR
)
6744 && TREE_CODE (tem
) == COND_EXPR
6745 && TREE_CODE (TREE_OPERAND (tem
, 1)) == code
6746 && TREE_CODE (TREE_OPERAND (tem
, 2)) == code
6747 && ! VOID_TYPE_P (TREE_OPERAND (tem
, 1))
6748 && ! VOID_TYPE_P (TREE_OPERAND (tem
, 2))
6749 && (TREE_TYPE (TREE_OPERAND (TREE_OPERAND (tem
, 1), 0))
6750 == TREE_TYPE (TREE_OPERAND (TREE_OPERAND (tem
, 2), 0)))
6751 && (! (INTEGRAL_TYPE_P (TREE_TYPE (tem
))
6753 (TREE_TYPE (TREE_OPERAND (TREE_OPERAND (tem
, 1), 0))))
6754 && TYPE_PRECISION (TREE_TYPE (tem
)) <= BITS_PER_WORD
)
6755 || flag_syntax_only
))
6756 tem
= build1 (code
, type
,
6758 TREE_TYPE (TREE_OPERAND
6759 (TREE_OPERAND (tem
, 1), 0)),
6760 TREE_OPERAND (tem
, 0),
6761 TREE_OPERAND (TREE_OPERAND (tem
, 1), 0),
6762 TREE_OPERAND (TREE_OPERAND (tem
, 2), 0)));
6765 else if (COMPARISON_CLASS_P (arg0
))
6767 if (TREE_CODE (type
) == BOOLEAN_TYPE
)
6769 arg0
= copy_node (arg0
);
6770 TREE_TYPE (arg0
) = type
;
6773 else if (TREE_CODE (type
) != INTEGER_TYPE
)
6774 return fold_build3 (COND_EXPR
, type
, arg0
,
6775 fold_build1 (code
, type
,
6777 fold_build1 (code
, type
,
6778 integer_zero_node
));
6787 case FIX_TRUNC_EXPR
:
6789 case FIX_FLOOR_EXPR
:
6790 case FIX_ROUND_EXPR
:
6791 if (TREE_TYPE (op0
) == type
)
6794 /* Handle cases of two conversions in a row. */
6795 if (TREE_CODE (op0
) == NOP_EXPR
6796 || TREE_CODE (op0
) == CONVERT_EXPR
)
6798 tree inside_type
= TREE_TYPE (TREE_OPERAND (op0
, 0));
6799 tree inter_type
= TREE_TYPE (op0
);
6800 int inside_int
= INTEGRAL_TYPE_P (inside_type
);
6801 int inside_ptr
= POINTER_TYPE_P (inside_type
);
6802 int inside_float
= FLOAT_TYPE_P (inside_type
);
6803 int inside_vec
= TREE_CODE (inside_type
) == VECTOR_TYPE
;
6804 unsigned int inside_prec
= TYPE_PRECISION (inside_type
);
6805 int inside_unsignedp
= TYPE_UNSIGNED (inside_type
);
6806 int inter_int
= INTEGRAL_TYPE_P (inter_type
);
6807 int inter_ptr
= POINTER_TYPE_P (inter_type
);
6808 int inter_float
= FLOAT_TYPE_P (inter_type
);
6809 int inter_vec
= TREE_CODE (inter_type
) == VECTOR_TYPE
;
6810 unsigned int inter_prec
= TYPE_PRECISION (inter_type
);
6811 int inter_unsignedp
= TYPE_UNSIGNED (inter_type
);
6812 int final_int
= INTEGRAL_TYPE_P (type
);
6813 int final_ptr
= POINTER_TYPE_P (type
);
6814 int final_float
= FLOAT_TYPE_P (type
);
6815 int final_vec
= TREE_CODE (type
) == VECTOR_TYPE
;
6816 unsigned int final_prec
= TYPE_PRECISION (type
);
6817 int final_unsignedp
= TYPE_UNSIGNED (type
);
6819 /* In addition to the cases of two conversions in a row
6820 handled below, if we are converting something to its own
6821 type via an object of identical or wider precision, neither
6822 conversion is needed. */
6823 if (TYPE_MAIN_VARIANT (inside_type
) == TYPE_MAIN_VARIANT (type
)
6824 && ((inter_int
&& final_int
) || (inter_float
&& final_float
))
6825 && inter_prec
>= final_prec
)
6826 return fold_build1 (code
, type
, TREE_OPERAND (op0
, 0));
6828 /* Likewise, if the intermediate and final types are either both
6829 float or both integer, we don't need the middle conversion if
6830 it is wider than the final type and doesn't change the signedness
6831 (for integers). Avoid this if the final type is a pointer
6832 since then we sometimes need the inner conversion. Likewise if
6833 the outer has a precision not equal to the size of its mode. */
6834 if ((((inter_int
|| inter_ptr
) && (inside_int
|| inside_ptr
))
6835 || (inter_float
&& inside_float
)
6836 || (inter_vec
&& inside_vec
))
6837 && inter_prec
>= inside_prec
6838 && (inter_float
|| inter_vec
6839 || inter_unsignedp
== inside_unsignedp
)
6840 && ! (final_prec
!= GET_MODE_BITSIZE (TYPE_MODE (type
))
6841 && TYPE_MODE (type
) == TYPE_MODE (inter_type
))
6843 && (! final_vec
|| inter_prec
== inside_prec
))
6844 return fold_build1 (code
, type
, TREE_OPERAND (op0
, 0));
6846 /* If we have a sign-extension of a zero-extended value, we can
6847 replace that by a single zero-extension. */
6848 if (inside_int
&& inter_int
&& final_int
6849 && inside_prec
< inter_prec
&& inter_prec
< final_prec
6850 && inside_unsignedp
&& !inter_unsignedp
)
6851 return fold_build1 (code
, type
, TREE_OPERAND (op0
, 0));
6853 /* Two conversions in a row are not needed unless:
6854 - some conversion is floating-point (overstrict for now), or
6855 - some conversion is a vector (overstrict for now), or
6856 - the intermediate type is narrower than both initial and
6858 - the intermediate type and innermost type differ in signedness,
6859 and the outermost type is wider than the intermediate, or
6860 - the initial type is a pointer type and the precisions of the
6861 intermediate and final types differ, or
6862 - the final type is a pointer type and the precisions of the
6863 initial and intermediate types differ. */
6864 if (! inside_float
&& ! inter_float
&& ! final_float
6865 && ! inside_vec
&& ! inter_vec
&& ! final_vec
6866 && (inter_prec
> inside_prec
|| inter_prec
> final_prec
)
6867 && ! (inside_int
&& inter_int
6868 && inter_unsignedp
!= inside_unsignedp
6869 && inter_prec
< final_prec
)
6870 && ((inter_unsignedp
&& inter_prec
> inside_prec
)
6871 == (final_unsignedp
&& final_prec
> inter_prec
))
6872 && ! (inside_ptr
&& inter_prec
!= final_prec
)
6873 && ! (final_ptr
&& inside_prec
!= inter_prec
)
6874 && ! (final_prec
!= GET_MODE_BITSIZE (TYPE_MODE (type
))
6875 && TYPE_MODE (type
) == TYPE_MODE (inter_type
))
6877 return fold_build1 (code
, type
, TREE_OPERAND (op0
, 0));
6880 if (TREE_CODE (op0
) == MODIFY_EXPR
6881 && TREE_CONSTANT (TREE_OPERAND (op0
, 1))
6882 /* Detect assigning a bitfield. */
6883 && !(TREE_CODE (TREE_OPERAND (op0
, 0)) == COMPONENT_REF
6884 && DECL_BIT_FIELD (TREE_OPERAND (TREE_OPERAND (op0
, 0), 1))))
6886 /* Don't leave an assignment inside a conversion
6887 unless assigning a bitfield. */
6888 tem
= fold_build1 (code
, type
, TREE_OPERAND (op0
, 1));
6889 /* First do the assignment, then return converted constant. */
6890 tem
= build2 (COMPOUND_EXPR
, TREE_TYPE (tem
), op0
, tem
);
6891 TREE_NO_WARNING (tem
) = 1;
6892 TREE_USED (tem
) = 1;
6896 /* Convert (T)(x & c) into (T)x & (T)c, if c is an integer
6897 constants (if x has signed type, the sign bit cannot be set
6898 in c). This folds extension into the BIT_AND_EXPR. */
6899 if (INTEGRAL_TYPE_P (type
)
6900 && TREE_CODE (type
) != BOOLEAN_TYPE
6901 && TREE_CODE (op0
) == BIT_AND_EXPR
6902 && TREE_CODE (TREE_OPERAND (op0
, 1)) == INTEGER_CST
)
6905 tree and0
= TREE_OPERAND (and, 0), and1
= TREE_OPERAND (and, 1);
6908 if (TYPE_UNSIGNED (TREE_TYPE (and))
6909 || (TYPE_PRECISION (type
)
6910 <= TYPE_PRECISION (TREE_TYPE (and))))
6912 else if (TYPE_PRECISION (TREE_TYPE (and1
))
6913 <= HOST_BITS_PER_WIDE_INT
6914 && host_integerp (and1
, 1))
6916 unsigned HOST_WIDE_INT cst
;
6918 cst
= tree_low_cst (and1
, 1);
6919 cst
&= (HOST_WIDE_INT
) -1
6920 << (TYPE_PRECISION (TREE_TYPE (and1
)) - 1);
6921 change
= (cst
== 0);
6922 #ifdef LOAD_EXTEND_OP
6924 && !flag_syntax_only
6925 && (LOAD_EXTEND_OP (TYPE_MODE (TREE_TYPE (and0
)))
6928 tree uns
= lang_hooks
.types
.unsigned_type (TREE_TYPE (and0
));
6929 and0
= fold_convert (uns
, and0
);
6930 and1
= fold_convert (uns
, and1
);
6936 tem
= build_int_cst_wide (type
, TREE_INT_CST_LOW (and1
),
6937 TREE_INT_CST_HIGH (and1
));
6938 tem
= force_fit_type (tem
, 0, TREE_OVERFLOW (and1
),
6939 TREE_CONSTANT_OVERFLOW (and1
));
6940 return fold_build2 (BIT_AND_EXPR
, type
,
6941 fold_convert (type
, and0
), tem
);
6945 /* Convert (T1)((T2)X op Y) into (T1)X op Y, for pointer types T1 and
6946 T2 being pointers to types of the same size. */
6947 if (POINTER_TYPE_P (type
)
6948 && BINARY_CLASS_P (arg0
)
6949 && TREE_CODE (TREE_OPERAND (arg0
, 0)) == NOP_EXPR
6950 && POINTER_TYPE_P (TREE_TYPE (TREE_OPERAND (arg0
, 0))))
6952 tree arg00
= TREE_OPERAND (arg0
, 0);
6954 tree t1
= TREE_TYPE (arg00
);
6955 tree tt0
= TREE_TYPE (t0
);
6956 tree tt1
= TREE_TYPE (t1
);
6957 tree s0
= TYPE_SIZE (tt0
);
6958 tree s1
= TYPE_SIZE (tt1
);
6960 if (s0
&& s1
&& operand_equal_p (s0
, s1
, OEP_ONLY_CONST
))
6961 return build2 (TREE_CODE (arg0
), t0
, fold_convert (t0
, arg00
),
6962 TREE_OPERAND (arg0
, 1));
6965 tem
= fold_convert_const (code
, type
, arg0
);
6966 return tem
? tem
: NULL_TREE
;
6968 case VIEW_CONVERT_EXPR
:
6969 if (TREE_CODE (op0
) == VIEW_CONVERT_EXPR
)
6970 return build1 (VIEW_CONVERT_EXPR
, type
, TREE_OPERAND (op0
, 0));
6974 if (negate_expr_p (arg0
))
6975 return fold_convert (type
, negate_expr (arg0
));
6976 /* Convert - (~A) to A + 1. */
6977 if (INTEGRAL_TYPE_P (type
) && TREE_CODE (arg0
) == BIT_NOT_EXPR
)
6978 return fold_build2 (PLUS_EXPR
, type
, TREE_OPERAND (arg0
, 0),
6979 build_int_cst (type
, 1));
6983 if (TREE_CODE (arg0
) == INTEGER_CST
|| TREE_CODE (arg0
) == REAL_CST
)
6984 return fold_abs_const (arg0
, type
);
6985 else if (TREE_CODE (arg0
) == NEGATE_EXPR
)
6986 return fold_build1 (ABS_EXPR
, type
, TREE_OPERAND (arg0
, 0));
6987 /* Convert fabs((double)float) into (double)fabsf(float). */
6988 else if (TREE_CODE (arg0
) == NOP_EXPR
6989 && TREE_CODE (type
) == REAL_TYPE
)
6991 tree targ0
= strip_float_extensions (arg0
);
6993 return fold_convert (type
, fold_build1 (ABS_EXPR
,
6997 else if (tree_expr_nonnegative_p (arg0
))
7000 /* Strip sign ops from argument. */
7001 if (TREE_CODE (type
) == REAL_TYPE
)
7003 tem
= fold_strip_sign_ops (arg0
);
7005 return fold_build1 (ABS_EXPR
, type
, fold_convert (type
, tem
));
7010 if (TREE_CODE (TREE_TYPE (arg0
)) != COMPLEX_TYPE
)
7011 return fold_convert (type
, arg0
);
7012 else if (TREE_CODE (arg0
) == COMPLEX_EXPR
)
7013 return build2 (COMPLEX_EXPR
, type
,
7014 TREE_OPERAND (arg0
, 0),
7015 negate_expr (TREE_OPERAND (arg0
, 1)));
7016 else if (TREE_CODE (arg0
) == COMPLEX_CST
)
7017 return build_complex (type
, TREE_REALPART (arg0
),
7018 negate_expr (TREE_IMAGPART (arg0
)));
7019 else if (TREE_CODE (arg0
) == PLUS_EXPR
|| TREE_CODE (arg0
) == MINUS_EXPR
)
7020 return fold_build2 (TREE_CODE (arg0
), type
,
7021 fold_build1 (CONJ_EXPR
, type
,
7022 TREE_OPERAND (arg0
, 0)),
7023 fold_build1 (CONJ_EXPR
, type
,
7024 TREE_OPERAND (arg0
, 1)));
7025 else if (TREE_CODE (arg0
) == CONJ_EXPR
)
7026 return TREE_OPERAND (arg0
, 0);
7030 if (TREE_CODE (arg0
) == INTEGER_CST
)
7031 return fold_not_const (arg0
, type
);
7032 else if (TREE_CODE (arg0
) == BIT_NOT_EXPR
)
7033 return TREE_OPERAND (arg0
, 0);
7034 /* Convert ~ (-A) to A - 1. */
7035 else if (INTEGRAL_TYPE_P (type
) && TREE_CODE (arg0
) == NEGATE_EXPR
)
7036 return fold_build2 (MINUS_EXPR
, type
, TREE_OPERAND (arg0
, 0),
7037 build_int_cst (type
, 1));
7038 /* Convert ~ (A - 1) or ~ (A + -1) to -A. */
7039 else if (INTEGRAL_TYPE_P (type
)
7040 && ((TREE_CODE (arg0
) == MINUS_EXPR
7041 && integer_onep (TREE_OPERAND (arg0
, 1)))
7042 || (TREE_CODE (arg0
) == PLUS_EXPR
7043 && integer_all_onesp (TREE_OPERAND (arg0
, 1)))))
7044 return fold_build1 (NEGATE_EXPR
, type
, TREE_OPERAND (arg0
, 0));
7045 /* Convert ~(X ^ Y) to ~X ^ Y or X ^ ~Y if ~X or ~Y simplify. */
7046 else if (TREE_CODE (arg0
) == BIT_XOR_EXPR
7047 && (tem
= fold_unary (BIT_NOT_EXPR
, type
,
7049 TREE_OPERAND (arg0
, 0)))))
7050 return fold_build2 (BIT_XOR_EXPR
, type
, tem
,
7051 fold_convert (type
, TREE_OPERAND (arg0
, 1)));
7052 else if (TREE_CODE (arg0
) == BIT_XOR_EXPR
7053 && (tem
= fold_unary (BIT_NOT_EXPR
, type
,
7055 TREE_OPERAND (arg0
, 1)))))
7056 return fold_build2 (BIT_XOR_EXPR
, type
,
7057 fold_convert (type
, TREE_OPERAND (arg0
, 0)), tem
);
7061 case TRUTH_NOT_EXPR
:
7062 /* The argument to invert_truthvalue must have Boolean type. */
7063 if (TREE_CODE (TREE_TYPE (arg0
)) != BOOLEAN_TYPE
)
7064 arg0
= fold_convert (boolean_type_node
, arg0
);
7066 /* Note that the operand of this must be an int
7067 and its values must be 0 or 1.
7068 ("true" is a fixed value perhaps depending on the language,
7069 but we don't handle values other than 1 correctly yet.) */
7070 tem
= invert_truthvalue (arg0
);
7071 /* Avoid infinite recursion. */
7072 if (TREE_CODE (tem
) == TRUTH_NOT_EXPR
)
7074 return fold_convert (type
, tem
);
7077 if (TREE_CODE (TREE_TYPE (arg0
)) != COMPLEX_TYPE
)
7079 else if (TREE_CODE (arg0
) == COMPLEX_EXPR
)
7080 return omit_one_operand (type
, TREE_OPERAND (arg0
, 0),
7081 TREE_OPERAND (arg0
, 1));
7082 else if (TREE_CODE (arg0
) == COMPLEX_CST
)
7083 return TREE_REALPART (arg0
);
7084 else if (TREE_CODE (arg0
) == PLUS_EXPR
|| TREE_CODE (arg0
) == MINUS_EXPR
)
7085 return fold_build2 (TREE_CODE (arg0
), type
,
7086 fold_build1 (REALPART_EXPR
, type
,
7087 TREE_OPERAND (arg0
, 0)),
7088 fold_build1 (REALPART_EXPR
, type
,
7089 TREE_OPERAND (arg0
, 1)));
7093 if (TREE_CODE (TREE_TYPE (arg0
)) != COMPLEX_TYPE
)
7094 return fold_convert (type
, integer_zero_node
);
7095 else if (TREE_CODE (arg0
) == COMPLEX_EXPR
)
7096 return omit_one_operand (type
, TREE_OPERAND (arg0
, 1),
7097 TREE_OPERAND (arg0
, 0));
7098 else if (TREE_CODE (arg0
) == COMPLEX_CST
)
7099 return TREE_IMAGPART (arg0
);
7100 else if (TREE_CODE (arg0
) == PLUS_EXPR
|| TREE_CODE (arg0
) == MINUS_EXPR
)
7101 return fold_build2 (TREE_CODE (arg0
), type
,
7102 fold_build1 (IMAGPART_EXPR
, type
,
7103 TREE_OPERAND (arg0
, 0)),
7104 fold_build1 (IMAGPART_EXPR
, type
,
7105 TREE_OPERAND (arg0
, 1)));
7110 } /* switch (code) */
7113 /* Fold a binary expression of code CODE and type TYPE with operands
7114 OP0 and OP1. Return the folded expression if folding is
7115 successful. Otherwise, return NULL_TREE. */
7118 fold_binary (enum tree_code code
, tree type
, tree op0
, tree op1
)
7120 tree t1
= NULL_TREE
;
7122 tree arg0
= NULL_TREE
, arg1
= NULL_TREE
;
7123 enum tree_code_class kind
= TREE_CODE_CLASS (code
);
7125 /* WINS will be nonzero when the switch is done
7126 if all operands are constant. */
7129 gcc_assert (IS_EXPR_CODE_CLASS (kind
)
7130 && TREE_CODE_LENGTH (code
) == 2);
7139 /* Strip any conversions that don't change the mode. This is
7140 safe for every expression, except for a comparison expression
7141 because its signedness is derived from its operands. So, in
7142 the latter case, only strip conversions that don't change the
7145 Note that this is done as an internal manipulation within the
7146 constant folder, in order to find the simplest representation
7147 of the arguments so that their form can be studied. In any
7148 cases, the appropriate type conversions should be put back in
7149 the tree that will get out of the constant folder. */
7150 if (kind
== tcc_comparison
)
7151 STRIP_SIGN_NOPS (arg0
);
7155 if (TREE_CODE (arg0
) == COMPLEX_CST
)
7156 subop
= TREE_REALPART (arg0
);
7160 if (TREE_CODE (subop
) != INTEGER_CST
7161 && TREE_CODE (subop
) != REAL_CST
)
7162 /* Note that TREE_CONSTANT isn't enough:
7163 static var addresses are constant but we can't
7164 do arithmetic on them. */
7172 /* Strip any conversions that don't change the mode. This is
7173 safe for every expression, except for a comparison expression
7174 because its signedness is derived from its operands. So, in
7175 the latter case, only strip conversions that don't change the
7178 Note that this is done as an internal manipulation within the
7179 constant folder, in order to find the simplest representation
7180 of the arguments so that their form can be studied. In any
7181 cases, the appropriate type conversions should be put back in
7182 the tree that will get out of the constant folder. */
7183 if (kind
== tcc_comparison
)
7184 STRIP_SIGN_NOPS (arg1
);
7188 if (TREE_CODE (arg1
) == COMPLEX_CST
)
7189 subop
= TREE_REALPART (arg1
);
7193 if (TREE_CODE (subop
) != INTEGER_CST
7194 && TREE_CODE (subop
) != REAL_CST
)
7195 /* Note that TREE_CONSTANT isn't enough:
7196 static var addresses are constant but we can't
7197 do arithmetic on them. */
7201 /* If this is a commutative operation, and ARG0 is a constant, move it
7202 to ARG1 to reduce the number of tests below. */
7203 if (commutative_tree_code (code
)
7204 && tree_swap_operands_p (arg0
, arg1
, true))
7205 return fold_build2 (code
, type
, op1
, op0
);
7207 /* Now WINS is set as described above,
7208 ARG0 is the first operand of EXPR,
7209 and ARG1 is the second operand (if it has more than one operand).
7211 First check for cases where an arithmetic operation is applied to a
7212 compound, conditional, or comparison operation. Push the arithmetic
7213 operation inside the compound or conditional to see if any folding
7214 can then be done. Convert comparison to conditional for this purpose.
7215 The also optimizes non-constant cases that used to be done in
7218 Before we do that, see if this is a BIT_AND_EXPR or a BIT_IOR_EXPR,
7219 one of the operands is a comparison and the other is a comparison, a
7220 BIT_AND_EXPR with the constant 1, or a truth value. In that case, the
7221 code below would make the expression more complex. Change it to a
7222 TRUTH_{AND,OR}_EXPR. Likewise, convert a similar NE_EXPR to
7223 TRUTH_XOR_EXPR and an EQ_EXPR to the inversion of a TRUTH_XOR_EXPR. */
7225 if ((code
== BIT_AND_EXPR
|| code
== BIT_IOR_EXPR
7226 || code
== EQ_EXPR
|| code
== NE_EXPR
)
7227 && ((truth_value_p (TREE_CODE (arg0
))
7228 && (truth_value_p (TREE_CODE (arg1
))
7229 || (TREE_CODE (arg1
) == BIT_AND_EXPR
7230 && integer_onep (TREE_OPERAND (arg1
, 1)))))
7231 || (truth_value_p (TREE_CODE (arg1
))
7232 && (truth_value_p (TREE_CODE (arg0
))
7233 || (TREE_CODE (arg0
) == BIT_AND_EXPR
7234 && integer_onep (TREE_OPERAND (arg0
, 1)))))))
7236 tem
= fold_build2 (code
== BIT_AND_EXPR
? TRUTH_AND_EXPR
7237 : code
== BIT_IOR_EXPR
? TRUTH_OR_EXPR
7240 fold_convert (boolean_type_node
, arg0
),
7241 fold_convert (boolean_type_node
, arg1
));
7243 if (code
== EQ_EXPR
)
7244 tem
= invert_truthvalue (tem
);
7246 return fold_convert (type
, tem
);
7249 if (TREE_CODE_CLASS (code
) == tcc_comparison
7250 && TREE_CODE (arg0
) == COMPOUND_EXPR
)
7251 return build2 (COMPOUND_EXPR
, type
, TREE_OPERAND (arg0
, 0),
7252 fold_build2 (code
, type
, TREE_OPERAND (arg0
, 1), arg1
));
7253 else if (TREE_CODE_CLASS (code
) == tcc_comparison
7254 && TREE_CODE (arg1
) == COMPOUND_EXPR
)
7255 return build2 (COMPOUND_EXPR
, type
, TREE_OPERAND (arg1
, 0),
7256 fold_build2 (code
, type
, arg0
, TREE_OPERAND (arg1
, 1)));
7257 else if (TREE_CODE_CLASS (code
) == tcc_binary
7258 || TREE_CODE_CLASS (code
) == tcc_comparison
)
7260 if (TREE_CODE (arg0
) == COMPOUND_EXPR
)
7261 return build2 (COMPOUND_EXPR
, type
, TREE_OPERAND (arg0
, 0),
7262 fold_build2 (code
, type
, TREE_OPERAND (arg0
, 1),
7264 if (TREE_CODE (arg1
) == COMPOUND_EXPR
7265 && reorder_operands_p (arg0
, TREE_OPERAND (arg1
, 0)))
7266 return build2 (COMPOUND_EXPR
, type
, TREE_OPERAND (arg1
, 0),
7267 fold_build2 (code
, type
,
7268 arg0
, TREE_OPERAND (arg1
, 1)));
7270 if (TREE_CODE (arg0
) == COND_EXPR
|| COMPARISON_CLASS_P (arg0
))
7272 tem
= fold_binary_op_with_conditional_arg (code
, type
, op0
, op1
,
7274 /*cond_first_p=*/1);
7275 if (tem
!= NULL_TREE
)
7279 if (TREE_CODE (arg1
) == COND_EXPR
|| COMPARISON_CLASS_P (arg1
))
7281 tem
= fold_binary_op_with_conditional_arg (code
, type
, op0
, op1
,
7283 /*cond_first_p=*/0);
7284 if (tem
!= NULL_TREE
)
7292 /* A + (-B) -> A - B */
7293 if (TREE_CODE (arg1
) == NEGATE_EXPR
)
7294 return fold_build2 (MINUS_EXPR
, type
,
7295 fold_convert (type
, arg0
),
7296 fold_convert (type
, TREE_OPERAND (arg1
, 0)));
7297 /* (-A) + B -> B - A */
7298 if (TREE_CODE (arg0
) == NEGATE_EXPR
7299 && reorder_operands_p (TREE_OPERAND (arg0
, 0), arg1
))
7300 return fold_build2 (MINUS_EXPR
, type
,
7301 fold_convert (type
, arg1
),
7302 fold_convert (type
, TREE_OPERAND (arg0
, 0)));
7303 /* Convert ~A + 1 to -A. */
7304 if (INTEGRAL_TYPE_P (type
)
7305 && TREE_CODE (arg0
) == BIT_NOT_EXPR
7306 && integer_onep (arg1
))
7307 return fold_build1 (NEGATE_EXPR
, type
, TREE_OPERAND (arg0
, 0));
7309 if (TREE_CODE (type
) == COMPLEX_TYPE
)
7311 tem
= fold_complex_add (type
, arg0
, arg1
, PLUS_EXPR
);
7316 if (! FLOAT_TYPE_P (type
))
7318 if (integer_zerop (arg1
))
7319 return non_lvalue (fold_convert (type
, arg0
));
7321 /* If we are adding two BIT_AND_EXPR's, both of which are and'ing
7322 with a constant, and the two constants have no bits in common,
7323 we should treat this as a BIT_IOR_EXPR since this may produce more
7325 if (TREE_CODE (arg0
) == BIT_AND_EXPR
7326 && TREE_CODE (arg1
) == BIT_AND_EXPR
7327 && TREE_CODE (TREE_OPERAND (arg0
, 1)) == INTEGER_CST
7328 && TREE_CODE (TREE_OPERAND (arg1
, 1)) == INTEGER_CST
7329 && integer_zerop (const_binop (BIT_AND_EXPR
,
7330 TREE_OPERAND (arg0
, 1),
7331 TREE_OPERAND (arg1
, 1), 0)))
7333 code
= BIT_IOR_EXPR
;
7337 /* Reassociate (plus (plus (mult) (foo)) (mult)) as
7338 (plus (plus (mult) (mult)) (foo)) so that we can
7339 take advantage of the factoring cases below. */
7340 if (((TREE_CODE (arg0
) == PLUS_EXPR
7341 || TREE_CODE (arg0
) == MINUS_EXPR
)
7342 && TREE_CODE (arg1
) == MULT_EXPR
)
7343 || ((TREE_CODE (arg1
) == PLUS_EXPR
7344 || TREE_CODE (arg1
) == MINUS_EXPR
)
7345 && TREE_CODE (arg0
) == MULT_EXPR
))
7347 tree parg0
, parg1
, parg
, marg
;
7348 enum tree_code pcode
;
7350 if (TREE_CODE (arg1
) == MULT_EXPR
)
7351 parg
= arg0
, marg
= arg1
;
7353 parg
= arg1
, marg
= arg0
;
7354 pcode
= TREE_CODE (parg
);
7355 parg0
= TREE_OPERAND (parg
, 0);
7356 parg1
= TREE_OPERAND (parg
, 1);
7360 if (TREE_CODE (parg0
) == MULT_EXPR
7361 && TREE_CODE (parg1
) != MULT_EXPR
)
7362 return fold_build2 (pcode
, type
,
7363 fold_build2 (PLUS_EXPR
, type
,
7364 fold_convert (type
, parg0
),
7365 fold_convert (type
, marg
)),
7366 fold_convert (type
, parg1
));
7367 if (TREE_CODE (parg0
) != MULT_EXPR
7368 && TREE_CODE (parg1
) == MULT_EXPR
)
7369 return fold_build2 (PLUS_EXPR
, type
,
7370 fold_convert (type
, parg0
),
7371 fold_build2 (pcode
, type
,
7372 fold_convert (type
, marg
),
7377 if (TREE_CODE (arg0
) == MULT_EXPR
&& TREE_CODE (arg1
) == MULT_EXPR
)
7379 tree arg00
, arg01
, arg10
, arg11
;
7380 tree alt0
= NULL_TREE
, alt1
= NULL_TREE
, same
;
7382 /* (A * C) + (B * C) -> (A+B) * C.
7383 We are most concerned about the case where C is a constant,
7384 but other combinations show up during loop reduction. Since
7385 it is not difficult, try all four possibilities. */
7387 arg00
= TREE_OPERAND (arg0
, 0);
7388 arg01
= TREE_OPERAND (arg0
, 1);
7389 arg10
= TREE_OPERAND (arg1
, 0);
7390 arg11
= TREE_OPERAND (arg1
, 1);
7393 if (operand_equal_p (arg01
, arg11
, 0))
7394 same
= arg01
, alt0
= arg00
, alt1
= arg10
;
7395 else if (operand_equal_p (arg00
, arg10
, 0))
7396 same
= arg00
, alt0
= arg01
, alt1
= arg11
;
7397 else if (operand_equal_p (arg00
, arg11
, 0))
7398 same
= arg00
, alt0
= arg01
, alt1
= arg10
;
7399 else if (operand_equal_p (arg01
, arg10
, 0))
7400 same
= arg01
, alt0
= arg00
, alt1
= arg11
;
7402 /* No identical multiplicands; see if we can find a common
7403 power-of-two factor in non-power-of-two multiplies. This
7404 can help in multi-dimensional array access. */
7405 else if (TREE_CODE (arg01
) == INTEGER_CST
7406 && TREE_CODE (arg11
) == INTEGER_CST
7407 && TREE_INT_CST_HIGH (arg01
) == 0
7408 && TREE_INT_CST_HIGH (arg11
) == 0)
7410 HOST_WIDE_INT int01
, int11
, tmp
;
7411 int01
= TREE_INT_CST_LOW (arg01
);
7412 int11
= TREE_INT_CST_LOW (arg11
);
7414 /* Move min of absolute values to int11. */
7415 if ((int01
>= 0 ? int01
: -int01
)
7416 < (int11
>= 0 ? int11
: -int11
))
7418 tmp
= int01
, int01
= int11
, int11
= tmp
;
7419 alt0
= arg00
, arg00
= arg10
, arg10
= alt0
;
7420 alt0
= arg01
, arg01
= arg11
, arg11
= alt0
;
7423 if (exact_log2 (int11
) > 0 && int01
% int11
== 0)
7425 alt0
= fold_build2 (MULT_EXPR
, type
, arg00
,
7426 build_int_cst (NULL_TREE
,
7434 return fold_build2 (MULT_EXPR
, type
,
7435 fold_build2 (PLUS_EXPR
, type
,
7436 fold_convert (type
, alt0
),
7437 fold_convert (type
, alt1
)),
7438 fold_convert (type
, same
));
7441 /* Try replacing &a[i1] + c * i2 with &a[i1 + i2], if c is step
7442 of the array. Loop optimizer sometimes produce this type of
7444 if (TREE_CODE (arg0
) == ADDR_EXPR
7445 && TREE_CODE (arg1
) == MULT_EXPR
)
7447 tem
= try_move_mult_to_index (PLUS_EXPR
, arg0
, arg1
);
7449 return fold_convert (type
, fold (tem
));
7451 else if (TREE_CODE (arg1
) == ADDR_EXPR
7452 && TREE_CODE (arg0
) == MULT_EXPR
)
7454 tem
= try_move_mult_to_index (PLUS_EXPR
, arg1
, arg0
);
7456 return fold_convert (type
, fold (tem
));
7461 /* See if ARG1 is zero and X + ARG1 reduces to X. */
7462 if (fold_real_zero_addition_p (TREE_TYPE (arg0
), arg1
, 0))
7463 return non_lvalue (fold_convert (type
, arg0
));
7465 /* Likewise if the operands are reversed. */
7466 if (fold_real_zero_addition_p (TREE_TYPE (arg1
), arg0
, 0))
7467 return non_lvalue (fold_convert (type
, arg1
));
7469 /* Convert X + -C into X - C. */
7470 if (TREE_CODE (arg1
) == REAL_CST
7471 && REAL_VALUE_NEGATIVE (TREE_REAL_CST (arg1
)))
7473 tem
= fold_negate_const (arg1
, type
);
7474 if (!TREE_OVERFLOW (arg1
) || !flag_trapping_math
)
7475 return fold_build2 (MINUS_EXPR
, type
,
7476 fold_convert (type
, arg0
),
7477 fold_convert (type
, tem
));
7480 /* Convert x+x into x*2.0. */
7481 if (operand_equal_p (arg0
, arg1
, 0)
7482 && SCALAR_FLOAT_TYPE_P (type
))
7483 return fold_build2 (MULT_EXPR
, type
, arg0
,
7484 build_real (type
, dconst2
));
7486 /* Convert x*c+x into x*(c+1). */
7487 if (flag_unsafe_math_optimizations
7488 && TREE_CODE (arg0
) == MULT_EXPR
7489 && TREE_CODE (TREE_OPERAND (arg0
, 1)) == REAL_CST
7490 && ! TREE_CONSTANT_OVERFLOW (TREE_OPERAND (arg0
, 1))
7491 && operand_equal_p (TREE_OPERAND (arg0
, 0), arg1
, 0))
7495 c
= TREE_REAL_CST (TREE_OPERAND (arg0
, 1));
7496 real_arithmetic (&c
, PLUS_EXPR
, &c
, &dconst1
);
7497 return fold_build2 (MULT_EXPR
, type
, arg1
,
7498 build_real (type
, c
));
7501 /* Convert x+x*c into x*(c+1). */
7502 if (flag_unsafe_math_optimizations
7503 && TREE_CODE (arg1
) == MULT_EXPR
7504 && TREE_CODE (TREE_OPERAND (arg1
, 1)) == REAL_CST
7505 && ! TREE_CONSTANT_OVERFLOW (TREE_OPERAND (arg1
, 1))
7506 && operand_equal_p (TREE_OPERAND (arg1
, 0), arg0
, 0))
7510 c
= TREE_REAL_CST (TREE_OPERAND (arg1
, 1));
7511 real_arithmetic (&c
, PLUS_EXPR
, &c
, &dconst1
);
7512 return fold_build2 (MULT_EXPR
, type
, arg0
,
7513 build_real (type
, c
));
7516 /* Convert x*c1+x*c2 into x*(c1+c2). */
7517 if (flag_unsafe_math_optimizations
7518 && TREE_CODE (arg0
) == MULT_EXPR
7519 && TREE_CODE (arg1
) == MULT_EXPR
7520 && TREE_CODE (TREE_OPERAND (arg0
, 1)) == REAL_CST
7521 && ! TREE_CONSTANT_OVERFLOW (TREE_OPERAND (arg0
, 1))
7522 && TREE_CODE (TREE_OPERAND (arg1
, 1)) == REAL_CST
7523 && ! TREE_CONSTANT_OVERFLOW (TREE_OPERAND (arg1
, 1))
7524 && operand_equal_p (TREE_OPERAND (arg0
, 0),
7525 TREE_OPERAND (arg1
, 0), 0))
7527 REAL_VALUE_TYPE c1
, c2
;
7529 c1
= TREE_REAL_CST (TREE_OPERAND (arg0
, 1));
7530 c2
= TREE_REAL_CST (TREE_OPERAND (arg1
, 1));
7531 real_arithmetic (&c1
, PLUS_EXPR
, &c1
, &c2
);
7532 return fold_build2 (MULT_EXPR
, type
,
7533 TREE_OPERAND (arg0
, 0),
7534 build_real (type
, c1
));
7536 /* Convert a + (b*c + d*e) into (a + b*c) + d*e. */
7537 if (flag_unsafe_math_optimizations
7538 && TREE_CODE (arg1
) == PLUS_EXPR
7539 && TREE_CODE (arg0
) != MULT_EXPR
)
7541 tree tree10
= TREE_OPERAND (arg1
, 0);
7542 tree tree11
= TREE_OPERAND (arg1
, 1);
7543 if (TREE_CODE (tree11
) == MULT_EXPR
7544 && TREE_CODE (tree10
) == MULT_EXPR
)
7547 tree0
= fold_build2 (PLUS_EXPR
, type
, arg0
, tree10
);
7548 return fold_build2 (PLUS_EXPR
, type
, tree0
, tree11
);
7551 /* Convert (b*c + d*e) + a into b*c + (d*e +a). */
7552 if (flag_unsafe_math_optimizations
7553 && TREE_CODE (arg0
) == PLUS_EXPR
7554 && TREE_CODE (arg1
) != MULT_EXPR
)
7556 tree tree00
= TREE_OPERAND (arg0
, 0);
7557 tree tree01
= TREE_OPERAND (arg0
, 1);
7558 if (TREE_CODE (tree01
) == MULT_EXPR
7559 && TREE_CODE (tree00
) == MULT_EXPR
)
7562 tree0
= fold_build2 (PLUS_EXPR
, type
, tree01
, arg1
);
7563 return fold_build2 (PLUS_EXPR
, type
, tree00
, tree0
);
7569 /* (A << C1) + (A >> C2) if A is unsigned and C1+C2 is the size of A
7570 is a rotate of A by C1 bits. */
7571 /* (A << B) + (A >> (Z - B)) if A is unsigned and Z is the size of A
7572 is a rotate of A by B bits. */
7574 enum tree_code code0
, code1
;
7575 code0
= TREE_CODE (arg0
);
7576 code1
= TREE_CODE (arg1
);
7577 if (((code0
== RSHIFT_EXPR
&& code1
== LSHIFT_EXPR
)
7578 || (code1
== RSHIFT_EXPR
&& code0
== LSHIFT_EXPR
))
7579 && operand_equal_p (TREE_OPERAND (arg0
, 0),
7580 TREE_OPERAND (arg1
, 0), 0)
7581 && TYPE_UNSIGNED (TREE_TYPE (TREE_OPERAND (arg0
, 0))))
7583 tree tree01
, tree11
;
7584 enum tree_code code01
, code11
;
7586 tree01
= TREE_OPERAND (arg0
, 1);
7587 tree11
= TREE_OPERAND (arg1
, 1);
7588 STRIP_NOPS (tree01
);
7589 STRIP_NOPS (tree11
);
7590 code01
= TREE_CODE (tree01
);
7591 code11
= TREE_CODE (tree11
);
7592 if (code01
== INTEGER_CST
7593 && code11
== INTEGER_CST
7594 && TREE_INT_CST_HIGH (tree01
) == 0
7595 && TREE_INT_CST_HIGH (tree11
) == 0
7596 && ((TREE_INT_CST_LOW (tree01
) + TREE_INT_CST_LOW (tree11
))
7597 == TYPE_PRECISION (TREE_TYPE (TREE_OPERAND (arg0
, 0)))))
7598 return build2 (LROTATE_EXPR
, type
, TREE_OPERAND (arg0
, 0),
7599 code0
== LSHIFT_EXPR
? tree01
: tree11
);
7600 else if (code11
== MINUS_EXPR
)
7602 tree tree110
, tree111
;
7603 tree110
= TREE_OPERAND (tree11
, 0);
7604 tree111
= TREE_OPERAND (tree11
, 1);
7605 STRIP_NOPS (tree110
);
7606 STRIP_NOPS (tree111
);
7607 if (TREE_CODE (tree110
) == INTEGER_CST
7608 && 0 == compare_tree_int (tree110
,
7610 (TREE_TYPE (TREE_OPERAND
7612 && operand_equal_p (tree01
, tree111
, 0))
7613 return build2 ((code0
== LSHIFT_EXPR
7616 type
, TREE_OPERAND (arg0
, 0), tree01
);
7618 else if (code01
== MINUS_EXPR
)
7620 tree tree010
, tree011
;
7621 tree010
= TREE_OPERAND (tree01
, 0);
7622 tree011
= TREE_OPERAND (tree01
, 1);
7623 STRIP_NOPS (tree010
);
7624 STRIP_NOPS (tree011
);
7625 if (TREE_CODE (tree010
) == INTEGER_CST
7626 && 0 == compare_tree_int (tree010
,
7628 (TREE_TYPE (TREE_OPERAND
7630 && operand_equal_p (tree11
, tree011
, 0))
7631 return build2 ((code0
!= LSHIFT_EXPR
7634 type
, TREE_OPERAND (arg0
, 0), tree11
);
7640 /* In most languages, can't associate operations on floats through
7641 parentheses. Rather than remember where the parentheses were, we
7642 don't associate floats at all, unless the user has specified
7643 -funsafe-math-optimizations. */
7646 && (! FLOAT_TYPE_P (type
) || flag_unsafe_math_optimizations
))
7648 tree var0
, con0
, lit0
, minus_lit0
;
7649 tree var1
, con1
, lit1
, minus_lit1
;
7651 /* Split both trees into variables, constants, and literals. Then
7652 associate each group together, the constants with literals,
7653 then the result with variables. This increases the chances of
7654 literals being recombined later and of generating relocatable
7655 expressions for the sum of a constant and literal. */
7656 var0
= split_tree (arg0
, code
, &con0
, &lit0
, &minus_lit0
, 0);
7657 var1
= split_tree (arg1
, code
, &con1
, &lit1
, &minus_lit1
,
7658 code
== MINUS_EXPR
);
7660 /* Only do something if we found more than two objects. Otherwise,
7661 nothing has changed and we risk infinite recursion. */
7662 if (2 < ((var0
!= 0) + (var1
!= 0)
7663 + (con0
!= 0) + (con1
!= 0)
7664 + (lit0
!= 0) + (lit1
!= 0)
7665 + (minus_lit0
!= 0) + (minus_lit1
!= 0)))
7667 /* Recombine MINUS_EXPR operands by using PLUS_EXPR. */
7668 if (code
== MINUS_EXPR
)
7671 var0
= associate_trees (var0
, var1
, code
, type
);
7672 con0
= associate_trees (con0
, con1
, code
, type
);
7673 lit0
= associate_trees (lit0
, lit1
, code
, type
);
7674 minus_lit0
= associate_trees (minus_lit0
, minus_lit1
, code
, type
);
7676 /* Preserve the MINUS_EXPR if the negative part of the literal is
7677 greater than the positive part. Otherwise, the multiplicative
7678 folding code (i.e extract_muldiv) may be fooled in case
7679 unsigned constants are subtracted, like in the following
7680 example: ((X*2 + 4) - 8U)/2. */
7681 if (minus_lit0
&& lit0
)
7683 if (TREE_CODE (lit0
) == INTEGER_CST
7684 && TREE_CODE (minus_lit0
) == INTEGER_CST
7685 && tree_int_cst_lt (lit0
, minus_lit0
))
7687 minus_lit0
= associate_trees (minus_lit0
, lit0
,
7693 lit0
= associate_trees (lit0
, minus_lit0
,
7701 return fold_convert (type
,
7702 associate_trees (var0
, minus_lit0
,
7706 con0
= associate_trees (con0
, minus_lit0
,
7708 return fold_convert (type
,
7709 associate_trees (var0
, con0
,
7714 con0
= associate_trees (con0
, lit0
, code
, type
);
7715 return fold_convert (type
, associate_trees (var0
, con0
,
7722 t1
= const_binop (code
, arg0
, arg1
, 0);
7723 if (t1
!= NULL_TREE
)
7725 /* The return value should always have
7726 the same type as the original expression. */
7727 if (TREE_TYPE (t1
) != type
)
7728 t1
= fold_convert (type
, t1
);
7735 /* A - (-B) -> A + B */
7736 if (TREE_CODE (arg1
) == NEGATE_EXPR
)
7737 return fold_build2 (PLUS_EXPR
, type
, arg0
, TREE_OPERAND (arg1
, 0));
7738 /* (-A) - B -> (-B) - A where B is easily negated and we can swap. */
7739 if (TREE_CODE (arg0
) == NEGATE_EXPR
7740 && (FLOAT_TYPE_P (type
)
7741 || (INTEGRAL_TYPE_P (type
) && flag_wrapv
&& !flag_trapv
))
7742 && negate_expr_p (arg1
)
7743 && reorder_operands_p (arg0
, arg1
))
7744 return fold_build2 (MINUS_EXPR
, type
, negate_expr (arg1
),
7745 TREE_OPERAND (arg0
, 0));
7746 /* Convert -A - 1 to ~A. */
7747 if (INTEGRAL_TYPE_P (type
)
7748 && TREE_CODE (arg0
) == NEGATE_EXPR
7749 && integer_onep (arg1
))
7750 return fold_build1 (BIT_NOT_EXPR
, type
, TREE_OPERAND (arg0
, 0));
7752 /* Convert -1 - A to ~A. */
7753 if (INTEGRAL_TYPE_P (type
)
7754 && integer_all_onesp (arg0
))
7755 return fold_build1 (BIT_NOT_EXPR
, type
, arg1
);
7757 if (TREE_CODE (type
) == COMPLEX_TYPE
)
7759 tem
= fold_complex_add (type
, arg0
, arg1
, MINUS_EXPR
);
7764 if (! FLOAT_TYPE_P (type
))
7766 if (! wins
&& integer_zerop (arg0
))
7767 return negate_expr (fold_convert (type
, arg1
));
7768 if (integer_zerop (arg1
))
7769 return non_lvalue (fold_convert (type
, arg0
));
7771 /* Fold A - (A & B) into ~B & A. */
7772 if (!TREE_SIDE_EFFECTS (arg0
)
7773 && TREE_CODE (arg1
) == BIT_AND_EXPR
)
7775 if (operand_equal_p (arg0
, TREE_OPERAND (arg1
, 1), 0))
7776 return fold_build2 (BIT_AND_EXPR
, type
,
7777 fold_build1 (BIT_NOT_EXPR
, type
,
7778 TREE_OPERAND (arg1
, 0)),
7780 if (operand_equal_p (arg0
, TREE_OPERAND (arg1
, 0), 0))
7781 return fold_build2 (BIT_AND_EXPR
, type
,
7782 fold_build1 (BIT_NOT_EXPR
, type
,
7783 TREE_OPERAND (arg1
, 1)),
7787 /* Fold (A & ~B) - (A & B) into (A ^ B) - B, where B is
7788 any power of 2 minus 1. */
7789 if (TREE_CODE (arg0
) == BIT_AND_EXPR
7790 && TREE_CODE (arg1
) == BIT_AND_EXPR
7791 && operand_equal_p (TREE_OPERAND (arg0
, 0),
7792 TREE_OPERAND (arg1
, 0), 0))
7794 tree mask0
= TREE_OPERAND (arg0
, 1);
7795 tree mask1
= TREE_OPERAND (arg1
, 1);
7796 tree tem
= fold_build1 (BIT_NOT_EXPR
, type
, mask0
);
7798 if (operand_equal_p (tem
, mask1
, 0))
7800 tem
= fold_build2 (BIT_XOR_EXPR
, type
,
7801 TREE_OPERAND (arg0
, 0), mask1
);
7802 return fold_build2 (MINUS_EXPR
, type
, tem
, mask1
);
7807 /* See if ARG1 is zero and X - ARG1 reduces to X. */
7808 else if (fold_real_zero_addition_p (TREE_TYPE (arg0
), arg1
, 1))
7809 return non_lvalue (fold_convert (type
, arg0
));
7811 /* (ARG0 - ARG1) is the same as (-ARG1 + ARG0). So check whether
7812 ARG0 is zero and X + ARG0 reduces to X, since that would mean
7813 (-ARG1 + ARG0) reduces to -ARG1. */
7814 else if (!wins
&& fold_real_zero_addition_p (TREE_TYPE (arg1
), arg0
, 0))
7815 return negate_expr (fold_convert (type
, arg1
));
7817 /* Fold &x - &x. This can happen from &x.foo - &x.
7818 This is unsafe for certain floats even in non-IEEE formats.
7819 In IEEE, it is unsafe because it does wrong for NaNs.
7820 Also note that operand_equal_p is always false if an operand
7823 if ((! FLOAT_TYPE_P (type
) || flag_unsafe_math_optimizations
)
7824 && operand_equal_p (arg0
, arg1
, 0))
7825 return fold_convert (type
, integer_zero_node
);
7827 /* A - B -> A + (-B) if B is easily negatable. */
7828 if (!wins
&& negate_expr_p (arg1
)
7829 && ((FLOAT_TYPE_P (type
)
7830 /* Avoid this transformation if B is a positive REAL_CST. */
7831 && (TREE_CODE (arg1
) != REAL_CST
7832 || REAL_VALUE_NEGATIVE (TREE_REAL_CST (arg1
))))
7833 || (INTEGRAL_TYPE_P (type
) && flag_wrapv
&& !flag_trapv
)))
7834 return fold_build2 (PLUS_EXPR
, type
, arg0
, negate_expr (arg1
));
7836 /* Try folding difference of addresses. */
7840 if ((TREE_CODE (arg0
) == ADDR_EXPR
7841 || TREE_CODE (arg1
) == ADDR_EXPR
)
7842 && ptr_difference_const (arg0
, arg1
, &diff
))
7843 return build_int_cst_type (type
, diff
);
7846 /* Fold &a[i] - &a[j] to i-j. */
7847 if (TREE_CODE (arg0
) == ADDR_EXPR
7848 && TREE_CODE (TREE_OPERAND (arg0
, 0)) == ARRAY_REF
7849 && TREE_CODE (arg1
) == ADDR_EXPR
7850 && TREE_CODE (TREE_OPERAND (arg1
, 0)) == ARRAY_REF
)
7852 tree aref0
= TREE_OPERAND (arg0
, 0);
7853 tree aref1
= TREE_OPERAND (arg1
, 0);
7854 if (operand_equal_p (TREE_OPERAND (aref0
, 0),
7855 TREE_OPERAND (aref1
, 0), 0))
7857 tree op0
= fold_convert (type
, TREE_OPERAND (aref0
, 1));
7858 tree op1
= fold_convert (type
, TREE_OPERAND (aref1
, 1));
7859 tree esz
= array_ref_element_size (aref0
);
7860 tree diff
= build2 (MINUS_EXPR
, type
, op0
, op1
);
7861 return fold_build2 (MULT_EXPR
, type
, diff
,
7862 fold_convert (type
, esz
));
7867 /* Try replacing &a[i1] - c * i2 with &a[i1 - i2], if c is step
7868 of the array. Loop optimizer sometimes produce this type of
7870 if (TREE_CODE (arg0
) == ADDR_EXPR
7871 && TREE_CODE (arg1
) == MULT_EXPR
)
7873 tem
= try_move_mult_to_index (MINUS_EXPR
, arg0
, arg1
);
7875 return fold_convert (type
, fold (tem
));
7878 if (TREE_CODE (arg0
) == MULT_EXPR
7879 && TREE_CODE (arg1
) == MULT_EXPR
7880 && (!FLOAT_TYPE_P (type
) || flag_unsafe_math_optimizations
))
7882 /* (A * C) - (B * C) -> (A-B) * C. */
7883 if (operand_equal_p (TREE_OPERAND (arg0
, 1),
7884 TREE_OPERAND (arg1
, 1), 0))
7885 return fold_build2 (MULT_EXPR
, type
,
7886 fold_build2 (MINUS_EXPR
, type
,
7887 TREE_OPERAND (arg0
, 0),
7888 TREE_OPERAND (arg1
, 0)),
7889 TREE_OPERAND (arg0
, 1));
7890 /* (A * C1) - (A * C2) -> A * (C1-C2). */
7891 if (operand_equal_p (TREE_OPERAND (arg0
, 0),
7892 TREE_OPERAND (arg1
, 0), 0))
7893 return fold_build2 (MULT_EXPR
, type
,
7894 TREE_OPERAND (arg0
, 0),
7895 fold_build2 (MINUS_EXPR
, type
,
7896 TREE_OPERAND (arg0
, 1),
7897 TREE_OPERAND (arg1
, 1)));
7903 /* (-A) * (-B) -> A * B */
7904 if (TREE_CODE (arg0
) == NEGATE_EXPR
&& negate_expr_p (arg1
))
7905 return fold_build2 (MULT_EXPR
, type
,
7906 TREE_OPERAND (arg0
, 0),
7907 negate_expr (arg1
));
7908 if (TREE_CODE (arg1
) == NEGATE_EXPR
&& negate_expr_p (arg0
))
7909 return fold_build2 (MULT_EXPR
, type
,
7911 TREE_OPERAND (arg1
, 0));
7913 if (TREE_CODE (type
) == COMPLEX_TYPE
)
7915 tem
= fold_complex_mult (type
, arg0
, arg1
);
7920 if (! FLOAT_TYPE_P (type
))
7922 if (integer_zerop (arg1
))
7923 return omit_one_operand (type
, arg1
, arg0
);
7924 if (integer_onep (arg1
))
7925 return non_lvalue (fold_convert (type
, arg0
));
7926 /* Transform x * -1 into -x. */
7927 if (integer_all_onesp (arg1
))
7928 return fold_convert (type
, negate_expr (arg0
));
7930 /* (a * (1 << b)) is (a << b) */
7931 if (TREE_CODE (arg1
) == LSHIFT_EXPR
7932 && integer_onep (TREE_OPERAND (arg1
, 0)))
7933 return fold_build2 (LSHIFT_EXPR
, type
, arg0
,
7934 TREE_OPERAND (arg1
, 1));
7935 if (TREE_CODE (arg0
) == LSHIFT_EXPR
7936 && integer_onep (TREE_OPERAND (arg0
, 0)))
7937 return fold_build2 (LSHIFT_EXPR
, type
, arg1
,
7938 TREE_OPERAND (arg0
, 1));
7940 if (TREE_CODE (arg1
) == INTEGER_CST
7941 && 0 != (tem
= extract_muldiv (op0
,
7942 fold_convert (type
, arg1
),
7944 return fold_convert (type
, tem
);
7949 /* Maybe fold x * 0 to 0. The expressions aren't the same
7950 when x is NaN, since x * 0 is also NaN. Nor are they the
7951 same in modes with signed zeros, since multiplying a
7952 negative value by 0 gives -0, not +0. */
7953 if (!HONOR_NANS (TYPE_MODE (TREE_TYPE (arg0
)))
7954 && !HONOR_SIGNED_ZEROS (TYPE_MODE (TREE_TYPE (arg0
)))
7955 && real_zerop (arg1
))
7956 return omit_one_operand (type
, arg1
, arg0
);
7957 /* In IEEE floating point, x*1 is not equivalent to x for snans. */
7958 if (!HONOR_SNANS (TYPE_MODE (TREE_TYPE (arg0
)))
7959 && real_onep (arg1
))
7960 return non_lvalue (fold_convert (type
, arg0
));
7962 /* Transform x * -1.0 into -x. */
7963 if (!HONOR_SNANS (TYPE_MODE (TREE_TYPE (arg0
)))
7964 && real_minus_onep (arg1
))
7965 return fold_convert (type
, negate_expr (arg0
));
7967 /* Convert (C1/X)*C2 into (C1*C2)/X. */
7968 if (flag_unsafe_math_optimizations
7969 && TREE_CODE (arg0
) == RDIV_EXPR
7970 && TREE_CODE (arg1
) == REAL_CST
7971 && TREE_CODE (TREE_OPERAND (arg0
, 0)) == REAL_CST
)
7973 tree tem
= const_binop (MULT_EXPR
, TREE_OPERAND (arg0
, 0),
7976 return fold_build2 (RDIV_EXPR
, type
, tem
,
7977 TREE_OPERAND (arg0
, 1));
7980 /* Strip sign operations from X in X*X, i.e. -Y*-Y -> Y*Y. */
7981 if (operand_equal_p (arg0
, arg1
, 0))
7983 tree tem
= fold_strip_sign_ops (arg0
);
7984 if (tem
!= NULL_TREE
)
7986 tem
= fold_convert (type
, tem
);
7987 return fold_build2 (MULT_EXPR
, type
, tem
, tem
);
7991 if (flag_unsafe_math_optimizations
)
7993 enum built_in_function fcode0
= builtin_mathfn_code (arg0
);
7994 enum built_in_function fcode1
= builtin_mathfn_code (arg1
);
7996 /* Optimizations of root(...)*root(...). */
7997 if (fcode0
== fcode1
&& BUILTIN_ROOT_P (fcode0
))
7999 tree rootfn
, arg
, arglist
;
8000 tree arg00
= TREE_VALUE (TREE_OPERAND (arg0
, 1));
8001 tree arg10
= TREE_VALUE (TREE_OPERAND (arg1
, 1));
8003 /* Optimize sqrt(x)*sqrt(x) as x. */
8004 if (BUILTIN_SQRT_P (fcode0
)
8005 && operand_equal_p (arg00
, arg10
, 0)
8006 && ! HONOR_SNANS (TYPE_MODE (type
)))
8009 /* Optimize root(x)*root(y) as root(x*y). */
8010 rootfn
= TREE_OPERAND (TREE_OPERAND (arg0
, 0), 0);
8011 arg
= fold_build2 (MULT_EXPR
, type
, arg00
, arg10
);
8012 arglist
= build_tree_list (NULL_TREE
, arg
);
8013 return build_function_call_expr (rootfn
, arglist
);
8016 /* Optimize expN(x)*expN(y) as expN(x+y). */
8017 if (fcode0
== fcode1
&& BUILTIN_EXPONENT_P (fcode0
))
8019 tree expfn
= TREE_OPERAND (TREE_OPERAND (arg0
, 0), 0);
8020 tree arg
= fold_build2 (PLUS_EXPR
, type
,
8021 TREE_VALUE (TREE_OPERAND (arg0
, 1)),
8022 TREE_VALUE (TREE_OPERAND (arg1
, 1)));
8023 tree arglist
= build_tree_list (NULL_TREE
, arg
);
8024 return build_function_call_expr (expfn
, arglist
);
8027 /* Optimizations of pow(...)*pow(...). */
8028 if ((fcode0
== BUILT_IN_POW
&& fcode1
== BUILT_IN_POW
)
8029 || (fcode0
== BUILT_IN_POWF
&& fcode1
== BUILT_IN_POWF
)
8030 || (fcode0
== BUILT_IN_POWL
&& fcode1
== BUILT_IN_POWL
))
8032 tree arg00
= TREE_VALUE (TREE_OPERAND (arg0
, 1));
8033 tree arg01
= TREE_VALUE (TREE_CHAIN (TREE_OPERAND (arg0
,
8035 tree arg10
= TREE_VALUE (TREE_OPERAND (arg1
, 1));
8036 tree arg11
= TREE_VALUE (TREE_CHAIN (TREE_OPERAND (arg1
,
8039 /* Optimize pow(x,y)*pow(z,y) as pow(x*z,y). */
8040 if (operand_equal_p (arg01
, arg11
, 0))
8042 tree powfn
= TREE_OPERAND (TREE_OPERAND (arg0
, 0), 0);
8043 tree arg
= fold_build2 (MULT_EXPR
, type
, arg00
, arg10
);
8044 tree arglist
= tree_cons (NULL_TREE
, arg
,
8045 build_tree_list (NULL_TREE
,
8047 return build_function_call_expr (powfn
, arglist
);
8050 /* Optimize pow(x,y)*pow(x,z) as pow(x,y+z). */
8051 if (operand_equal_p (arg00
, arg10
, 0))
8053 tree powfn
= TREE_OPERAND (TREE_OPERAND (arg0
, 0), 0);
8054 tree arg
= fold_build2 (PLUS_EXPR
, type
, arg01
, arg11
);
8055 tree arglist
= tree_cons (NULL_TREE
, arg00
,
8056 build_tree_list (NULL_TREE
,
8058 return build_function_call_expr (powfn
, arglist
);
8062 /* Optimize tan(x)*cos(x) as sin(x). */
8063 if (((fcode0
== BUILT_IN_TAN
&& fcode1
== BUILT_IN_COS
)
8064 || (fcode0
== BUILT_IN_TANF
&& fcode1
== BUILT_IN_COSF
)
8065 || (fcode0
== BUILT_IN_TANL
&& fcode1
== BUILT_IN_COSL
)
8066 || (fcode0
== BUILT_IN_COS
&& fcode1
== BUILT_IN_TAN
)
8067 || (fcode0
== BUILT_IN_COSF
&& fcode1
== BUILT_IN_TANF
)
8068 || (fcode0
== BUILT_IN_COSL
&& fcode1
== BUILT_IN_TANL
))
8069 && operand_equal_p (TREE_VALUE (TREE_OPERAND (arg0
, 1)),
8070 TREE_VALUE (TREE_OPERAND (arg1
, 1)), 0))
8072 tree sinfn
= mathfn_built_in (type
, BUILT_IN_SIN
);
8074 if (sinfn
!= NULL_TREE
)
8075 return build_function_call_expr (sinfn
,
8076 TREE_OPERAND (arg0
, 1));
8079 /* Optimize x*pow(x,c) as pow(x,c+1). */
8080 if (fcode1
== BUILT_IN_POW
8081 || fcode1
== BUILT_IN_POWF
8082 || fcode1
== BUILT_IN_POWL
)
8084 tree arg10
= TREE_VALUE (TREE_OPERAND (arg1
, 1));
8085 tree arg11
= TREE_VALUE (TREE_CHAIN (TREE_OPERAND (arg1
,
8087 if (TREE_CODE (arg11
) == REAL_CST
8088 && ! TREE_CONSTANT_OVERFLOW (arg11
)
8089 && operand_equal_p (arg0
, arg10
, 0))
8091 tree powfn
= TREE_OPERAND (TREE_OPERAND (arg1
, 0), 0);
8095 c
= TREE_REAL_CST (arg11
);
8096 real_arithmetic (&c
, PLUS_EXPR
, &c
, &dconst1
);
8097 arg
= build_real (type
, c
);
8098 arglist
= build_tree_list (NULL_TREE
, arg
);
8099 arglist
= tree_cons (NULL_TREE
, arg0
, arglist
);
8100 return build_function_call_expr (powfn
, arglist
);
8104 /* Optimize pow(x,c)*x as pow(x,c+1). */
8105 if (fcode0
== BUILT_IN_POW
8106 || fcode0
== BUILT_IN_POWF
8107 || fcode0
== BUILT_IN_POWL
)
8109 tree arg00
= TREE_VALUE (TREE_OPERAND (arg0
, 1));
8110 tree arg01
= TREE_VALUE (TREE_CHAIN (TREE_OPERAND (arg0
,
8112 if (TREE_CODE (arg01
) == REAL_CST
8113 && ! TREE_CONSTANT_OVERFLOW (arg01
)
8114 && operand_equal_p (arg1
, arg00
, 0))
8116 tree powfn
= TREE_OPERAND (TREE_OPERAND (arg0
, 0), 0);
8120 c
= TREE_REAL_CST (arg01
);
8121 real_arithmetic (&c
, PLUS_EXPR
, &c
, &dconst1
);
8122 arg
= build_real (type
, c
);
8123 arglist
= build_tree_list (NULL_TREE
, arg
);
8124 arglist
= tree_cons (NULL_TREE
, arg1
, arglist
);
8125 return build_function_call_expr (powfn
, arglist
);
8129 /* Optimize x*x as pow(x,2.0), which is expanded as x*x. */
8131 && operand_equal_p (arg0
, arg1
, 0))
8133 tree powfn
= mathfn_built_in (type
, BUILT_IN_POW
);
8137 tree arg
= build_real (type
, dconst2
);
8138 tree arglist
= build_tree_list (NULL_TREE
, arg
);
8139 arglist
= tree_cons (NULL_TREE
, arg0
, arglist
);
8140 return build_function_call_expr (powfn
, arglist
);
8149 if (integer_all_onesp (arg1
))
8150 return omit_one_operand (type
, arg1
, arg0
);
8151 if (integer_zerop (arg1
))
8152 return non_lvalue (fold_convert (type
, arg0
));
8153 if (operand_equal_p (arg0
, arg1
, 0))
8154 return non_lvalue (fold_convert (type
, arg0
));
8157 if (TREE_CODE (arg0
) == BIT_NOT_EXPR
8158 && operand_equal_p (TREE_OPERAND (arg0
, 0), arg1
, 0))
8160 t1
= build_int_cst (type
, -1);
8161 t1
= force_fit_type (t1
, 0, false, false);
8162 return omit_one_operand (type
, t1
, arg1
);
8166 if (TREE_CODE (arg1
) == BIT_NOT_EXPR
8167 && operand_equal_p (arg0
, TREE_OPERAND (arg1
, 0), 0))
8169 t1
= build_int_cst (type
, -1);
8170 t1
= force_fit_type (t1
, 0, false, false);
8171 return omit_one_operand (type
, t1
, arg0
);
8174 t1
= distribute_bit_expr (code
, type
, arg0
, arg1
);
8175 if (t1
!= NULL_TREE
)
8178 /* Convert (or (not arg0) (not arg1)) to (not (and (arg0) (arg1))).
8180 This results in more efficient code for machines without a NAND
8181 instruction. Combine will canonicalize to the first form
8182 which will allow use of NAND instructions provided by the
8183 backend if they exist. */
8184 if (TREE_CODE (arg0
) == BIT_NOT_EXPR
8185 && TREE_CODE (arg1
) == BIT_NOT_EXPR
)
8187 return fold_build1 (BIT_NOT_EXPR
, type
,
8188 build2 (BIT_AND_EXPR
, type
,
8189 TREE_OPERAND (arg0
, 0),
8190 TREE_OPERAND (arg1
, 0)));
8193 /* See if this can be simplified into a rotate first. If that
8194 is unsuccessful continue in the association code. */
8198 if (integer_zerop (arg1
))
8199 return non_lvalue (fold_convert (type
, arg0
));
8200 if (integer_all_onesp (arg1
))
8201 return fold_build1 (BIT_NOT_EXPR
, type
, arg0
);
8202 if (operand_equal_p (arg0
, arg1
, 0))
8203 return omit_one_operand (type
, integer_zero_node
, arg0
);
8206 if (TREE_CODE (arg0
) == BIT_NOT_EXPR
8207 && operand_equal_p (TREE_OPERAND (arg0
, 0), arg1
, 0))
8209 t1
= build_int_cst (type
, -1);
8210 t1
= force_fit_type (t1
, 0, false, false);
8211 return omit_one_operand (type
, t1
, arg1
);
8215 if (TREE_CODE (arg1
) == BIT_NOT_EXPR
8216 && operand_equal_p (arg0
, TREE_OPERAND (arg1
, 0), 0))
8218 t1
= build_int_cst (type
, -1);
8219 t1
= force_fit_type (t1
, 0, false, false);
8220 return omit_one_operand (type
, t1
, arg0
);
8223 /* If we are XORing two BIT_AND_EXPR's, both of which are and'ing
8224 with a constant, and the two constants have no bits in common,
8225 we should treat this as a BIT_IOR_EXPR since this may produce more
8227 if (TREE_CODE (arg0
) == BIT_AND_EXPR
8228 && TREE_CODE (arg1
) == BIT_AND_EXPR
8229 && TREE_CODE (TREE_OPERAND (arg0
, 1)) == INTEGER_CST
8230 && TREE_CODE (TREE_OPERAND (arg1
, 1)) == INTEGER_CST
8231 && integer_zerop (const_binop (BIT_AND_EXPR
,
8232 TREE_OPERAND (arg0
, 1),
8233 TREE_OPERAND (arg1
, 1), 0)))
8235 code
= BIT_IOR_EXPR
;
8239 /* Convert ~X ^ ~Y to X ^ Y. */
8240 if (TREE_CODE (arg0
) == BIT_NOT_EXPR
8241 && TREE_CODE (arg1
) == BIT_NOT_EXPR
)
8242 return fold_build2 (code
, type
,
8243 fold_convert (type
, TREE_OPERAND (arg0
, 0)),
8244 fold_convert (type
, TREE_OPERAND (arg1
, 0)));
8246 /* See if this can be simplified into a rotate first. If that
8247 is unsuccessful continue in the association code. */
8251 if (integer_all_onesp (arg1
))
8252 return non_lvalue (fold_convert (type
, arg0
));
8253 if (integer_zerop (arg1
))
8254 return omit_one_operand (type
, arg1
, arg0
);
8255 if (operand_equal_p (arg0
, arg1
, 0))
8256 return non_lvalue (fold_convert (type
, arg0
));
8258 /* ~X & X is always zero. */
8259 if (TREE_CODE (arg0
) == BIT_NOT_EXPR
8260 && operand_equal_p (TREE_OPERAND (arg0
, 0), arg1
, 0))
8261 return omit_one_operand (type
, integer_zero_node
, arg1
);
8263 /* X & ~X is always zero. */
8264 if (TREE_CODE (arg1
) == BIT_NOT_EXPR
8265 && operand_equal_p (arg0
, TREE_OPERAND (arg1
, 0), 0))
8266 return omit_one_operand (type
, integer_zero_node
, arg0
);
8268 t1
= distribute_bit_expr (code
, type
, arg0
, arg1
);
8269 if (t1
!= NULL_TREE
)
8271 /* Simplify ((int)c & 0377) into (int)c, if c is unsigned char. */
8272 if (TREE_CODE (arg1
) == INTEGER_CST
&& TREE_CODE (arg0
) == NOP_EXPR
8273 && TYPE_UNSIGNED (TREE_TYPE (TREE_OPERAND (arg0
, 0))))
8276 = TYPE_PRECISION (TREE_TYPE (TREE_OPERAND (arg0
, 0)));
8278 if (prec
< BITS_PER_WORD
&& prec
< HOST_BITS_PER_WIDE_INT
8279 && (~TREE_INT_CST_LOW (arg1
)
8280 & (((HOST_WIDE_INT
) 1 << prec
) - 1)) == 0)
8281 return fold_convert (type
, TREE_OPERAND (arg0
, 0));
8284 /* Convert (and (not arg0) (not arg1)) to (not (or (arg0) (arg1))).
8286 This results in more efficient code for machines without a NOR
8287 instruction. Combine will canonicalize to the first form
8288 which will allow use of NOR instructions provided by the
8289 backend if they exist. */
8290 if (TREE_CODE (arg0
) == BIT_NOT_EXPR
8291 && TREE_CODE (arg1
) == BIT_NOT_EXPR
)
8293 return fold_build1 (BIT_NOT_EXPR
, type
,
8294 build2 (BIT_IOR_EXPR
, type
,
8295 TREE_OPERAND (arg0
, 0),
8296 TREE_OPERAND (arg1
, 0)));
8302 /* Don't touch a floating-point divide by zero unless the mode
8303 of the constant can represent infinity. */
8304 if (TREE_CODE (arg1
) == REAL_CST
8305 && !MODE_HAS_INFINITIES (TYPE_MODE (TREE_TYPE (arg1
)))
8306 && real_zerop (arg1
))
8309 /* (-A) / (-B) -> A / B */
8310 if (TREE_CODE (arg0
) == NEGATE_EXPR
&& negate_expr_p (arg1
))
8311 return fold_build2 (RDIV_EXPR
, type
,
8312 TREE_OPERAND (arg0
, 0),
8313 negate_expr (arg1
));
8314 if (TREE_CODE (arg1
) == NEGATE_EXPR
&& negate_expr_p (arg0
))
8315 return fold_build2 (RDIV_EXPR
, type
,
8317 TREE_OPERAND (arg1
, 0));
8319 /* In IEEE floating point, x/1 is not equivalent to x for snans. */
8320 if (!HONOR_SNANS (TYPE_MODE (TREE_TYPE (arg0
)))
8321 && real_onep (arg1
))
8322 return non_lvalue (fold_convert (type
, arg0
));
8324 /* In IEEE floating point, x/-1 is not equivalent to -x for snans. */
8325 if (!HONOR_SNANS (TYPE_MODE (TREE_TYPE (arg0
)))
8326 && real_minus_onep (arg1
))
8327 return non_lvalue (fold_convert (type
, negate_expr (arg0
)));
8329 /* If ARG1 is a constant, we can convert this to a multiply by the
8330 reciprocal. This does not have the same rounding properties,
8331 so only do this if -funsafe-math-optimizations. We can actually
8332 always safely do it if ARG1 is a power of two, but it's hard to
8333 tell if it is or not in a portable manner. */
8334 if (TREE_CODE (arg1
) == REAL_CST
)
8336 if (flag_unsafe_math_optimizations
8337 && 0 != (tem
= const_binop (code
, build_real (type
, dconst1
),
8339 return fold_build2 (MULT_EXPR
, type
, arg0
, tem
);
8340 /* Find the reciprocal if optimizing and the result is exact. */
8344 r
= TREE_REAL_CST (arg1
);
8345 if (exact_real_inverse (TYPE_MODE(TREE_TYPE(arg0
)), &r
))
8347 tem
= build_real (type
, r
);
8348 return fold_build2 (MULT_EXPR
, type
, arg0
, tem
);
8352 /* Convert A/B/C to A/(B*C). */
8353 if (flag_unsafe_math_optimizations
8354 && TREE_CODE (arg0
) == RDIV_EXPR
)
8355 return fold_build2 (RDIV_EXPR
, type
, TREE_OPERAND (arg0
, 0),
8356 fold_build2 (MULT_EXPR
, type
,
8357 TREE_OPERAND (arg0
, 1), arg1
));
8359 /* Convert A/(B/C) to (A/B)*C. */
8360 if (flag_unsafe_math_optimizations
8361 && TREE_CODE (arg1
) == RDIV_EXPR
)
8362 return fold_build2 (MULT_EXPR
, type
,
8363 fold_build2 (RDIV_EXPR
, type
, arg0
,
8364 TREE_OPERAND (arg1
, 0)),
8365 TREE_OPERAND (arg1
, 1));
8367 /* Convert C1/(X*C2) into (C1/C2)/X. */
8368 if (flag_unsafe_math_optimizations
8369 && TREE_CODE (arg1
) == MULT_EXPR
8370 && TREE_CODE (arg0
) == REAL_CST
8371 && TREE_CODE (TREE_OPERAND (arg1
, 1)) == REAL_CST
)
8373 tree tem
= const_binop (RDIV_EXPR
, arg0
,
8374 TREE_OPERAND (arg1
, 1), 0);
8376 return fold_build2 (RDIV_EXPR
, type
, tem
,
8377 TREE_OPERAND (arg1
, 0));
8380 if (TREE_CODE (type
) == COMPLEX_TYPE
)
8382 tem
= fold_complex_div (type
, arg0
, arg1
, code
);
8387 if (flag_unsafe_math_optimizations
)
8389 enum built_in_function fcode
= builtin_mathfn_code (arg1
);
8390 /* Optimize x/expN(y) into x*expN(-y). */
8391 if (BUILTIN_EXPONENT_P (fcode
))
8393 tree expfn
= TREE_OPERAND (TREE_OPERAND (arg1
, 0), 0);
8394 tree arg
= negate_expr (TREE_VALUE (TREE_OPERAND (arg1
, 1)));
8395 tree arglist
= build_tree_list (NULL_TREE
,
8396 fold_convert (type
, arg
));
8397 arg1
= build_function_call_expr (expfn
, arglist
);
8398 return fold_build2 (MULT_EXPR
, type
, arg0
, arg1
);
8401 /* Optimize x/pow(y,z) into x*pow(y,-z). */
8402 if (fcode
== BUILT_IN_POW
8403 || fcode
== BUILT_IN_POWF
8404 || fcode
== BUILT_IN_POWL
)
8406 tree powfn
= TREE_OPERAND (TREE_OPERAND (arg1
, 0), 0);
8407 tree arg10
= TREE_VALUE (TREE_OPERAND (arg1
, 1));
8408 tree arg11
= TREE_VALUE (TREE_CHAIN (TREE_OPERAND (arg1
, 1)));
8409 tree neg11
= fold_convert (type
, negate_expr (arg11
));
8410 tree arglist
= tree_cons(NULL_TREE
, arg10
,
8411 build_tree_list (NULL_TREE
, neg11
));
8412 arg1
= build_function_call_expr (powfn
, arglist
);
8413 return fold_build2 (MULT_EXPR
, type
, arg0
, arg1
);
8417 if (flag_unsafe_math_optimizations
)
8419 enum built_in_function fcode0
= builtin_mathfn_code (arg0
);
8420 enum built_in_function fcode1
= builtin_mathfn_code (arg1
);
8422 /* Optimize sin(x)/cos(x) as tan(x). */
8423 if (((fcode0
== BUILT_IN_SIN
&& fcode1
== BUILT_IN_COS
)
8424 || (fcode0
== BUILT_IN_SINF
&& fcode1
== BUILT_IN_COSF
)
8425 || (fcode0
== BUILT_IN_SINL
&& fcode1
== BUILT_IN_COSL
))
8426 && operand_equal_p (TREE_VALUE (TREE_OPERAND (arg0
, 1)),
8427 TREE_VALUE (TREE_OPERAND (arg1
, 1)), 0))
8429 tree tanfn
= mathfn_built_in (type
, BUILT_IN_TAN
);
8431 if (tanfn
!= NULL_TREE
)
8432 return build_function_call_expr (tanfn
,
8433 TREE_OPERAND (arg0
, 1));
8436 /* Optimize cos(x)/sin(x) as 1.0/tan(x). */
8437 if (((fcode0
== BUILT_IN_COS
&& fcode1
== BUILT_IN_SIN
)
8438 || (fcode0
== BUILT_IN_COSF
&& fcode1
== BUILT_IN_SINF
)
8439 || (fcode0
== BUILT_IN_COSL
&& fcode1
== BUILT_IN_SINL
))
8440 && operand_equal_p (TREE_VALUE (TREE_OPERAND (arg0
, 1)),
8441 TREE_VALUE (TREE_OPERAND (arg1
, 1)), 0))
8443 tree tanfn
= mathfn_built_in (type
, BUILT_IN_TAN
);
8445 if (tanfn
!= NULL_TREE
)
8447 tree tmp
= TREE_OPERAND (arg0
, 1);
8448 tmp
= build_function_call_expr (tanfn
, tmp
);
8449 return fold_build2 (RDIV_EXPR
, type
,
8450 build_real (type
, dconst1
), tmp
);
8454 /* Optimize pow(x,c)/x as pow(x,c-1). */
8455 if (fcode0
== BUILT_IN_POW
8456 || fcode0
== BUILT_IN_POWF
8457 || fcode0
== BUILT_IN_POWL
)
8459 tree arg00
= TREE_VALUE (TREE_OPERAND (arg0
, 1));
8460 tree arg01
= TREE_VALUE (TREE_CHAIN (TREE_OPERAND (arg0
, 1)));
8461 if (TREE_CODE (arg01
) == REAL_CST
8462 && ! TREE_CONSTANT_OVERFLOW (arg01
)
8463 && operand_equal_p (arg1
, arg00
, 0))
8465 tree powfn
= TREE_OPERAND (TREE_OPERAND (arg0
, 0), 0);
8469 c
= TREE_REAL_CST (arg01
);
8470 real_arithmetic (&c
, MINUS_EXPR
, &c
, &dconst1
);
8471 arg
= build_real (type
, c
);
8472 arglist
= build_tree_list (NULL_TREE
, arg
);
8473 arglist
= tree_cons (NULL_TREE
, arg1
, arglist
);
8474 return build_function_call_expr (powfn
, arglist
);
8480 case TRUNC_DIV_EXPR
:
8481 case ROUND_DIV_EXPR
:
8482 case FLOOR_DIV_EXPR
:
8484 case EXACT_DIV_EXPR
:
8485 if (integer_onep (arg1
))
8486 return non_lvalue (fold_convert (type
, arg0
));
8487 if (integer_zerop (arg1
))
8490 if (!TYPE_UNSIGNED (type
)
8491 && TREE_CODE (arg1
) == INTEGER_CST
8492 && TREE_INT_CST_LOW (arg1
) == (unsigned HOST_WIDE_INT
) -1
8493 && TREE_INT_CST_HIGH (arg1
) == -1)
8494 return fold_convert (type
, negate_expr (arg0
));
8496 /* If arg0 is a multiple of arg1, then rewrite to the fastest div
8497 operation, EXACT_DIV_EXPR.
8499 Note that only CEIL_DIV_EXPR and FLOOR_DIV_EXPR are rewritten now.
8500 At one time others generated faster code, it's not clear if they do
8501 after the last round to changes to the DIV code in expmed.c. */
8502 if ((code
== CEIL_DIV_EXPR
|| code
== FLOOR_DIV_EXPR
)
8503 && multiple_of_p (type
, arg0
, arg1
))
8504 return fold_build2 (EXACT_DIV_EXPR
, type
, arg0
, arg1
);
8506 if (TREE_CODE (arg1
) == INTEGER_CST
8507 && 0 != (tem
= extract_muldiv (op0
, arg1
, code
, NULL_TREE
)))
8508 return fold_convert (type
, tem
);
8510 if (TREE_CODE (type
) == COMPLEX_TYPE
)
8512 tem
= fold_complex_div (type
, arg0
, arg1
, code
);
8519 case FLOOR_MOD_EXPR
:
8520 case ROUND_MOD_EXPR
:
8521 case TRUNC_MOD_EXPR
:
8522 /* X % 1 is always zero, but be sure to preserve any side
8524 if (integer_onep (arg1
))
8525 return omit_one_operand (type
, integer_zero_node
, arg0
);
8527 /* X % 0, return X % 0 unchanged so that we can get the
8528 proper warnings and errors. */
8529 if (integer_zerop (arg1
))
8532 /* 0 % X is always zero, but be sure to preserve any side
8533 effects in X. Place this after checking for X == 0. */
8534 if (integer_zerop (arg0
))
8535 return omit_one_operand (type
, integer_zero_node
, arg1
);
8537 /* X % -1 is zero. */
8538 if (!TYPE_UNSIGNED (type
)
8539 && TREE_CODE (arg1
) == INTEGER_CST
8540 && TREE_INT_CST_LOW (arg1
) == (unsigned HOST_WIDE_INT
) -1
8541 && TREE_INT_CST_HIGH (arg1
) == -1)
8542 return omit_one_operand (type
, integer_zero_node
, arg0
);
8544 /* Optimize unsigned TRUNC_MOD_EXPR by a power of two into a
8545 BIT_AND_EXPR, i.e. "X % C" into "X & C2". */
8546 if (code
== TRUNC_MOD_EXPR
8547 && TYPE_UNSIGNED (type
)
8548 && integer_pow2p (arg1
))
8550 unsigned HOST_WIDE_INT high
, low
;
8554 l
= tree_log2 (arg1
);
8555 if (l
>= HOST_BITS_PER_WIDE_INT
)
8557 high
= ((unsigned HOST_WIDE_INT
) 1
8558 << (l
- HOST_BITS_PER_WIDE_INT
)) - 1;
8564 low
= ((unsigned HOST_WIDE_INT
) 1 << l
) - 1;
8567 mask
= build_int_cst_wide (type
, low
, high
);
8568 return fold_build2 (BIT_AND_EXPR
, type
,
8569 fold_convert (type
, arg0
), mask
);
8572 /* X % -C is the same as X % C. */
8573 if (code
== TRUNC_MOD_EXPR
8574 && !TYPE_UNSIGNED (type
)
8575 && TREE_CODE (arg1
) == INTEGER_CST
8576 && !TREE_CONSTANT_OVERFLOW (arg1
)
8577 && TREE_INT_CST_HIGH (arg1
) < 0
8579 /* Avoid this transformation if C is INT_MIN, i.e. C == -C. */
8580 && !sign_bit_p (arg1
, arg1
))
8581 return fold_build2 (code
, type
, fold_convert (type
, arg0
),
8582 fold_convert (type
, negate_expr (arg1
)));
8584 /* X % -Y is the same as X % Y. */
8585 if (code
== TRUNC_MOD_EXPR
8586 && !TYPE_UNSIGNED (type
)
8587 && TREE_CODE (arg1
) == NEGATE_EXPR
8589 return fold_build2 (code
, type
, fold_convert (type
, arg0
),
8590 fold_convert (type
, TREE_OPERAND (arg1
, 0)));
8592 if (TREE_CODE (arg1
) == INTEGER_CST
8593 && 0 != (tem
= extract_muldiv (op0
, arg1
, code
, NULL_TREE
)))
8594 return fold_convert (type
, tem
);
8600 if (integer_all_onesp (arg0
))
8601 return omit_one_operand (type
, arg0
, arg1
);
8605 /* Optimize -1 >> x for arithmetic right shifts. */
8606 if (integer_all_onesp (arg0
) && !TYPE_UNSIGNED (type
))
8607 return omit_one_operand (type
, arg0
, arg1
);
8608 /* ... fall through ... */
8612 if (integer_zerop (arg1
))
8613 return non_lvalue (fold_convert (type
, arg0
));
8614 if (integer_zerop (arg0
))
8615 return omit_one_operand (type
, arg0
, arg1
);
8617 /* Since negative shift count is not well-defined,
8618 don't try to compute it in the compiler. */
8619 if (TREE_CODE (arg1
) == INTEGER_CST
&& tree_int_cst_sgn (arg1
) < 0)
8621 /* Rewrite an LROTATE_EXPR by a constant into an
8622 RROTATE_EXPR by a new constant. */
8623 if (code
== LROTATE_EXPR
&& TREE_CODE (arg1
) == INTEGER_CST
)
8625 tree tem
= build_int_cst (NULL_TREE
,
8626 GET_MODE_BITSIZE (TYPE_MODE (type
)));
8627 tem
= fold_convert (TREE_TYPE (arg1
), tem
);
8628 tem
= const_binop (MINUS_EXPR
, tem
, arg1
, 0);
8629 return fold_build2 (RROTATE_EXPR
, type
, arg0
, tem
);
8632 /* If we have a rotate of a bit operation with the rotate count and
8633 the second operand of the bit operation both constant,
8634 permute the two operations. */
8635 if (code
== RROTATE_EXPR
&& TREE_CODE (arg1
) == INTEGER_CST
8636 && (TREE_CODE (arg0
) == BIT_AND_EXPR
8637 || TREE_CODE (arg0
) == BIT_IOR_EXPR
8638 || TREE_CODE (arg0
) == BIT_XOR_EXPR
)
8639 && TREE_CODE (TREE_OPERAND (arg0
, 1)) == INTEGER_CST
)
8640 return fold_build2 (TREE_CODE (arg0
), type
,
8641 fold_build2 (code
, type
,
8642 TREE_OPERAND (arg0
, 0), arg1
),
8643 fold_build2 (code
, type
,
8644 TREE_OPERAND (arg0
, 1), arg1
));
8646 /* Two consecutive rotates adding up to the width of the mode can
8648 if (code
== RROTATE_EXPR
&& TREE_CODE (arg1
) == INTEGER_CST
8649 && TREE_CODE (arg0
) == RROTATE_EXPR
8650 && TREE_CODE (TREE_OPERAND (arg0
, 1)) == INTEGER_CST
8651 && TREE_INT_CST_HIGH (arg1
) == 0
8652 && TREE_INT_CST_HIGH (TREE_OPERAND (arg0
, 1)) == 0
8653 && ((TREE_INT_CST_LOW (arg1
)
8654 + TREE_INT_CST_LOW (TREE_OPERAND (arg0
, 1)))
8655 == (unsigned int) GET_MODE_BITSIZE (TYPE_MODE (type
))))
8656 return TREE_OPERAND (arg0
, 0);
8661 if (operand_equal_p (arg0
, arg1
, 0))
8662 return omit_one_operand (type
, arg0
, arg1
);
8663 if (INTEGRAL_TYPE_P (type
)
8664 && operand_equal_p (arg1
, TYPE_MIN_VALUE (type
), OEP_ONLY_CONST
))
8665 return omit_one_operand (type
, arg1
, arg0
);
8669 if (operand_equal_p (arg0
, arg1
, 0))
8670 return omit_one_operand (type
, arg0
, arg1
);
8671 if (INTEGRAL_TYPE_P (type
)
8672 && TYPE_MAX_VALUE (type
)
8673 && operand_equal_p (arg1
, TYPE_MAX_VALUE (type
), OEP_ONLY_CONST
))
8674 return omit_one_operand (type
, arg1
, arg0
);
8677 case TRUTH_ANDIF_EXPR
:
8678 /* Note that the operands of this must be ints
8679 and their values must be 0 or 1.
8680 ("true" is a fixed value perhaps depending on the language.) */
8681 /* If first arg is constant zero, return it. */
8682 if (integer_zerop (arg0
))
8683 return fold_convert (type
, arg0
);
8684 case TRUTH_AND_EXPR
:
8685 /* If either arg is constant true, drop it. */
8686 if (TREE_CODE (arg0
) == INTEGER_CST
&& ! integer_zerop (arg0
))
8687 return non_lvalue (fold_convert (type
, arg1
));
8688 if (TREE_CODE (arg1
) == INTEGER_CST
&& ! integer_zerop (arg1
)
8689 /* Preserve sequence points. */
8690 && (code
!= TRUTH_ANDIF_EXPR
|| ! TREE_SIDE_EFFECTS (arg0
)))
8691 return non_lvalue (fold_convert (type
, arg0
));
8692 /* If second arg is constant zero, result is zero, but first arg
8693 must be evaluated. */
8694 if (integer_zerop (arg1
))
8695 return omit_one_operand (type
, arg1
, arg0
);
8696 /* Likewise for first arg, but note that only the TRUTH_AND_EXPR
8697 case will be handled here. */
8698 if (integer_zerop (arg0
))
8699 return omit_one_operand (type
, arg0
, arg1
);
8701 /* !X && X is always false. */
8702 if (TREE_CODE (arg0
) == TRUTH_NOT_EXPR
8703 && operand_equal_p (TREE_OPERAND (arg0
, 0), arg1
, 0))
8704 return omit_one_operand (type
, integer_zero_node
, arg1
);
8705 /* X && !X is always false. */
8706 if (TREE_CODE (arg1
) == TRUTH_NOT_EXPR
8707 && operand_equal_p (arg0
, TREE_OPERAND (arg1
, 0), 0))
8708 return omit_one_operand (type
, integer_zero_node
, arg0
);
8710 /* A < X && A + 1 > Y ==> A < X && A >= Y. Normally A + 1 > Y
8711 means A >= Y && A != MAX, but in this case we know that
8714 if (!TREE_SIDE_EFFECTS (arg0
)
8715 && !TREE_SIDE_EFFECTS (arg1
))
8717 tem
= fold_to_nonsharp_ineq_using_bound (arg0
, arg1
);
8719 return fold_build2 (code
, type
, tem
, arg1
);
8721 tem
= fold_to_nonsharp_ineq_using_bound (arg1
, arg0
);
8723 return fold_build2 (code
, type
, arg0
, tem
);
8727 /* We only do these simplifications if we are optimizing. */
8731 /* Check for things like (A || B) && (A || C). We can convert this
8732 to A || (B && C). Note that either operator can be any of the four
8733 truth and/or operations and the transformation will still be
8734 valid. Also note that we only care about order for the
8735 ANDIF and ORIF operators. If B contains side effects, this
8736 might change the truth-value of A. */
8737 if (TREE_CODE (arg0
) == TREE_CODE (arg1
)
8738 && (TREE_CODE (arg0
) == TRUTH_ANDIF_EXPR
8739 || TREE_CODE (arg0
) == TRUTH_ORIF_EXPR
8740 || TREE_CODE (arg0
) == TRUTH_AND_EXPR
8741 || TREE_CODE (arg0
) == TRUTH_OR_EXPR
)
8742 && ! TREE_SIDE_EFFECTS (TREE_OPERAND (arg0
, 1)))
8744 tree a00
= TREE_OPERAND (arg0
, 0);
8745 tree a01
= TREE_OPERAND (arg0
, 1);
8746 tree a10
= TREE_OPERAND (arg1
, 0);
8747 tree a11
= TREE_OPERAND (arg1
, 1);
8748 int commutative
= ((TREE_CODE (arg0
) == TRUTH_OR_EXPR
8749 || TREE_CODE (arg0
) == TRUTH_AND_EXPR
)
8750 && (code
== TRUTH_AND_EXPR
8751 || code
== TRUTH_OR_EXPR
));
8753 if (operand_equal_p (a00
, a10
, 0))
8754 return fold_build2 (TREE_CODE (arg0
), type
, a00
,
8755 fold_build2 (code
, type
, a01
, a11
));
8756 else if (commutative
&& operand_equal_p (a00
, a11
, 0))
8757 return fold_build2 (TREE_CODE (arg0
), type
, a00
,
8758 fold_build2 (code
, type
, a01
, a10
));
8759 else if (commutative
&& operand_equal_p (a01
, a10
, 0))
8760 return fold_build2 (TREE_CODE (arg0
), type
, a01
,
8761 fold_build2 (code
, type
, a00
, a11
));
8763 /* This case if tricky because we must either have commutative
8764 operators or else A10 must not have side-effects. */
8766 else if ((commutative
|| ! TREE_SIDE_EFFECTS (a10
))
8767 && operand_equal_p (a01
, a11
, 0))
8768 return fold_build2 (TREE_CODE (arg0
), type
,
8769 fold_build2 (code
, type
, a00
, a10
),
8773 /* See if we can build a range comparison. */
8774 if (0 != (tem
= fold_range_test (code
, type
, op0
, op1
)))
8777 /* Check for the possibility of merging component references. If our
8778 lhs is another similar operation, try to merge its rhs with our
8779 rhs. Then try to merge our lhs and rhs. */
8780 if (TREE_CODE (arg0
) == code
8781 && 0 != (tem
= fold_truthop (code
, type
,
8782 TREE_OPERAND (arg0
, 1), arg1
)))
8783 return fold_build2 (code
, type
, TREE_OPERAND (arg0
, 0), tem
);
8785 if ((tem
= fold_truthop (code
, type
, arg0
, arg1
)) != 0)
8790 case TRUTH_ORIF_EXPR
:
8791 /* Note that the operands of this must be ints
8792 and their values must be 0 or true.
8793 ("true" is a fixed value perhaps depending on the language.) */
8794 /* If first arg is constant true, return it. */
8795 if (TREE_CODE (arg0
) == INTEGER_CST
&& ! integer_zerop (arg0
))
8796 return fold_convert (type
, arg0
);
8798 /* If either arg is constant zero, drop it. */
8799 if (TREE_CODE (arg0
) == INTEGER_CST
&& integer_zerop (arg0
))
8800 return non_lvalue (fold_convert (type
, arg1
));
8801 if (TREE_CODE (arg1
) == INTEGER_CST
&& integer_zerop (arg1
)
8802 /* Preserve sequence points. */
8803 && (code
!= TRUTH_ORIF_EXPR
|| ! TREE_SIDE_EFFECTS (arg0
)))
8804 return non_lvalue (fold_convert (type
, arg0
));
8805 /* If second arg is constant true, result is true, but we must
8806 evaluate first arg. */
8807 if (TREE_CODE (arg1
) == INTEGER_CST
&& ! integer_zerop (arg1
))
8808 return omit_one_operand (type
, arg1
, arg0
);
8809 /* Likewise for first arg, but note this only occurs here for
8811 if (TREE_CODE (arg0
) == INTEGER_CST
&& ! integer_zerop (arg0
))
8812 return omit_one_operand (type
, arg0
, arg1
);
8814 /* !X || X is always true. */
8815 if (TREE_CODE (arg0
) == TRUTH_NOT_EXPR
8816 && operand_equal_p (TREE_OPERAND (arg0
, 0), arg1
, 0))
8817 return omit_one_operand (type
, integer_one_node
, arg1
);
8818 /* X || !X is always true. */
8819 if (TREE_CODE (arg1
) == TRUTH_NOT_EXPR
8820 && operand_equal_p (arg0
, TREE_OPERAND (arg1
, 0), 0))
8821 return omit_one_operand (type
, integer_one_node
, arg0
);
8825 case TRUTH_XOR_EXPR
:
8826 /* If the second arg is constant zero, drop it. */
8827 if (integer_zerop (arg1
))
8828 return non_lvalue (fold_convert (type
, arg0
));
8829 /* If the second arg is constant true, this is a logical inversion. */
8830 if (integer_onep (arg1
))
8832 /* Only call invert_truthvalue if operand is a truth value. */
8833 if (TREE_CODE (TREE_TYPE (arg0
)) != BOOLEAN_TYPE
)
8834 tem
= fold_build1 (TRUTH_NOT_EXPR
, TREE_TYPE (arg0
), arg0
);
8836 tem
= invert_truthvalue (arg0
);
8837 return non_lvalue (fold_convert (type
, tem
));
8839 /* Identical arguments cancel to zero. */
8840 if (operand_equal_p (arg0
, arg1
, 0))
8841 return omit_one_operand (type
, integer_zero_node
, arg0
);
8843 /* !X ^ X is always true. */
8844 if (TREE_CODE (arg0
) == TRUTH_NOT_EXPR
8845 && operand_equal_p (TREE_OPERAND (arg0
, 0), arg1
, 0))
8846 return omit_one_operand (type
, integer_one_node
, arg1
);
8848 /* X ^ !X is always true. */
8849 if (TREE_CODE (arg1
) == TRUTH_NOT_EXPR
8850 && operand_equal_p (arg0
, TREE_OPERAND (arg1
, 0), 0))
8851 return omit_one_operand (type
, integer_one_node
, arg0
);
8861 /* If one arg is a real or integer constant, put it last. */
8862 if (tree_swap_operands_p (arg0
, arg1
, true))
8863 return fold_build2 (swap_tree_comparison (code
), type
, op1
, op0
);
8865 /* bool_var != 0 becomes bool_var. */
8866 if (TREE_CODE (TREE_TYPE (arg0
)) == BOOLEAN_TYPE
&& integer_zerop (arg1
)
8868 return non_lvalue (fold_convert (type
, arg0
));
8870 /* bool_var == 1 becomes bool_var. */
8871 if (TREE_CODE (TREE_TYPE (arg0
)) == BOOLEAN_TYPE
&& integer_onep (arg1
)
8873 return non_lvalue (fold_convert (type
, arg0
));
8875 /* If this is an equality comparison of the address of a non-weak
8876 object against zero, then we know the result. */
8877 if ((code
== EQ_EXPR
|| code
== NE_EXPR
)
8878 && TREE_CODE (arg0
) == ADDR_EXPR
8879 && DECL_P (TREE_OPERAND (arg0
, 0))
8880 && ! DECL_WEAK (TREE_OPERAND (arg0
, 0))
8881 && integer_zerop (arg1
))
8882 return constant_boolean_node (code
!= EQ_EXPR
, type
);
8884 /* If this is an equality comparison of the address of two non-weak,
8885 unaliased symbols neither of which are extern (since we do not
8886 have access to attributes for externs), then we know the result. */
8887 if ((code
== EQ_EXPR
|| code
== NE_EXPR
)
8888 && TREE_CODE (arg0
) == ADDR_EXPR
8889 && DECL_P (TREE_OPERAND (arg0
, 0))
8890 && ! DECL_WEAK (TREE_OPERAND (arg0
, 0))
8891 && ! lookup_attribute ("alias",
8892 DECL_ATTRIBUTES (TREE_OPERAND (arg0
, 0)))
8893 && ! DECL_EXTERNAL (TREE_OPERAND (arg0
, 0))
8894 && TREE_CODE (arg1
) == ADDR_EXPR
8895 && DECL_P (TREE_OPERAND (arg1
, 0))
8896 && ! DECL_WEAK (TREE_OPERAND (arg1
, 0))
8897 && ! lookup_attribute ("alias",
8898 DECL_ATTRIBUTES (TREE_OPERAND (arg1
, 0)))
8899 && ! DECL_EXTERNAL (TREE_OPERAND (arg1
, 0)))
8900 return constant_boolean_node (operand_equal_p (arg0
, arg1
, 0)
8901 ? code
== EQ_EXPR
: code
!= EQ_EXPR
,
8904 /* If this is a comparison of two exprs that look like an
8905 ARRAY_REF of the same object, then we can fold this to a
8906 comparison of the two offsets. */
8907 if (TREE_CODE_CLASS (code
) == tcc_comparison
)
8909 tree base0
, offset0
, base1
, offset1
;
8911 if (extract_array_ref (arg0
, &base0
, &offset0
)
8912 && extract_array_ref (arg1
, &base1
, &offset1
)
8913 && operand_equal_p (base0
, base1
, 0))
8915 if (offset0
== NULL_TREE
8916 && offset1
== NULL_TREE
)
8918 offset0
= integer_zero_node
;
8919 offset1
= integer_zero_node
;
8921 else if (offset0
== NULL_TREE
)
8922 offset0
= build_int_cst (TREE_TYPE (offset1
), 0);
8923 else if (offset1
== NULL_TREE
)
8924 offset1
= build_int_cst (TREE_TYPE (offset0
), 0);
8926 if (TREE_TYPE (offset0
) == TREE_TYPE (offset1
))
8927 return fold_build2 (code
, type
, offset0
, offset1
);
8931 /* Transform comparisons of the form X +- C CMP X. */
8932 if ((code
!= EQ_EXPR
&& code
!= NE_EXPR
)
8933 && (TREE_CODE (arg0
) == PLUS_EXPR
|| TREE_CODE (arg0
) == MINUS_EXPR
)
8934 && operand_equal_p (TREE_OPERAND (arg0
, 0), arg1
, 0)
8935 && ((TREE_CODE (TREE_OPERAND (arg0
, 1)) == REAL_CST
8936 && !HONOR_SNANS (TYPE_MODE (TREE_TYPE (arg0
))))
8937 || (TREE_CODE (TREE_OPERAND (arg0
, 1)) == INTEGER_CST
8938 && !TYPE_UNSIGNED (TREE_TYPE (arg1
))
8939 && !(flag_wrapv
|| flag_trapv
))))
8941 tree arg01
= TREE_OPERAND (arg0
, 1);
8942 enum tree_code code0
= TREE_CODE (arg0
);
8945 if (TREE_CODE (arg01
) == REAL_CST
)
8946 is_positive
= REAL_VALUE_NEGATIVE (TREE_REAL_CST (arg01
)) ? -1 : 1;
8948 is_positive
= tree_int_cst_sgn (arg01
);
8950 /* (X - c) > X becomes false. */
8952 && ((code0
== MINUS_EXPR
&& is_positive
>= 0)
8953 || (code0
== PLUS_EXPR
&& is_positive
<= 0)))
8954 return constant_boolean_node (0, type
);
8956 /* Likewise (X + c) < X becomes false. */
8958 && ((code0
== PLUS_EXPR
&& is_positive
>= 0)
8959 || (code0
== MINUS_EXPR
&& is_positive
<= 0)))
8960 return constant_boolean_node (0, type
);
8962 /* Convert (X - c) <= X to true. */
8963 if (!HONOR_NANS (TYPE_MODE (TREE_TYPE (arg1
)))
8965 && ((code0
== MINUS_EXPR
&& is_positive
>= 0)
8966 || (code0
== PLUS_EXPR
&& is_positive
<= 0)))
8967 return constant_boolean_node (1, type
);
8969 /* Convert (X + c) >= X to true. */
8970 if (!HONOR_NANS (TYPE_MODE (TREE_TYPE (arg1
)))
8972 && ((code0
== PLUS_EXPR
&& is_positive
>= 0)
8973 || (code0
== MINUS_EXPR
&& is_positive
<= 0)))
8974 return constant_boolean_node (1, type
);
8976 if (TREE_CODE (arg01
) == INTEGER_CST
)
8978 /* Convert X + c > X and X - c < X to true for integers. */
8980 && ((code0
== PLUS_EXPR
&& is_positive
> 0)
8981 || (code0
== MINUS_EXPR
&& is_positive
< 0)))
8982 return constant_boolean_node (1, type
);
8985 && ((code0
== MINUS_EXPR
&& is_positive
> 0)
8986 || (code0
== PLUS_EXPR
&& is_positive
< 0)))
8987 return constant_boolean_node (1, type
);
8989 /* Convert X + c <= X and X - c >= X to false for integers. */
8991 && ((code0
== PLUS_EXPR
&& is_positive
> 0)
8992 || (code0
== MINUS_EXPR
&& is_positive
< 0)))
8993 return constant_boolean_node (0, type
);
8996 && ((code0
== MINUS_EXPR
&& is_positive
> 0)
8997 || (code0
== PLUS_EXPR
&& is_positive
< 0)))
8998 return constant_boolean_node (0, type
);
9002 if (FLOAT_TYPE_P (TREE_TYPE (arg0
)))
9004 tree targ0
= strip_float_extensions (arg0
);
9005 tree targ1
= strip_float_extensions (arg1
);
9006 tree newtype
= TREE_TYPE (targ0
);
9008 if (TYPE_PRECISION (TREE_TYPE (targ1
)) > TYPE_PRECISION (newtype
))
9009 newtype
= TREE_TYPE (targ1
);
9011 /* Fold (double)float1 CMP (double)float2 into float1 CMP float2. */
9012 if (TYPE_PRECISION (newtype
) < TYPE_PRECISION (TREE_TYPE (arg0
)))
9013 return fold_build2 (code
, type
, fold_convert (newtype
, targ0
),
9014 fold_convert (newtype
, targ1
));
9016 /* (-a) CMP (-b) -> b CMP a */
9017 if (TREE_CODE (arg0
) == NEGATE_EXPR
9018 && TREE_CODE (arg1
) == NEGATE_EXPR
)
9019 return fold_build2 (code
, type
, TREE_OPERAND (arg1
, 0),
9020 TREE_OPERAND (arg0
, 0));
9022 if (TREE_CODE (arg1
) == REAL_CST
)
9024 REAL_VALUE_TYPE cst
;
9025 cst
= TREE_REAL_CST (arg1
);
9027 /* (-a) CMP CST -> a swap(CMP) (-CST) */
9028 if (TREE_CODE (arg0
) == NEGATE_EXPR
)
9030 fold_build2 (swap_tree_comparison (code
), type
,
9031 TREE_OPERAND (arg0
, 0),
9032 build_real (TREE_TYPE (arg1
),
9033 REAL_VALUE_NEGATE (cst
)));
9035 /* IEEE doesn't distinguish +0 and -0 in comparisons. */
9036 /* a CMP (-0) -> a CMP 0 */
9037 if (REAL_VALUE_MINUS_ZERO (cst
))
9038 return fold_build2 (code
, type
, arg0
,
9039 build_real (TREE_TYPE (arg1
), dconst0
));
9041 /* x != NaN is always true, other ops are always false. */
9042 if (REAL_VALUE_ISNAN (cst
)
9043 && ! HONOR_SNANS (TYPE_MODE (TREE_TYPE (arg1
))))
9045 tem
= (code
== NE_EXPR
) ? integer_one_node
: integer_zero_node
;
9046 return omit_one_operand (type
, tem
, arg0
);
9049 /* Fold comparisons against infinity. */
9050 if (REAL_VALUE_ISINF (cst
))
9052 tem
= fold_inf_compare (code
, type
, arg0
, arg1
);
9053 if (tem
!= NULL_TREE
)
9058 /* If this is a comparison of a real constant with a PLUS_EXPR
9059 or a MINUS_EXPR of a real constant, we can convert it into a
9060 comparison with a revised real constant as long as no overflow
9061 occurs when unsafe_math_optimizations are enabled. */
9062 if (flag_unsafe_math_optimizations
9063 && TREE_CODE (arg1
) == REAL_CST
9064 && (TREE_CODE (arg0
) == PLUS_EXPR
9065 || TREE_CODE (arg0
) == MINUS_EXPR
)
9066 && TREE_CODE (TREE_OPERAND (arg0
, 1)) == REAL_CST
9067 && 0 != (tem
= const_binop (TREE_CODE (arg0
) == PLUS_EXPR
9068 ? MINUS_EXPR
: PLUS_EXPR
,
9069 arg1
, TREE_OPERAND (arg0
, 1), 0))
9070 && ! TREE_CONSTANT_OVERFLOW (tem
))
9071 return fold_build2 (code
, type
, TREE_OPERAND (arg0
, 0), tem
);
9073 /* Likewise, we can simplify a comparison of a real constant with
9074 a MINUS_EXPR whose first operand is also a real constant, i.e.
9075 (c1 - x) < c2 becomes x > c1-c2. */
9076 if (flag_unsafe_math_optimizations
9077 && TREE_CODE (arg1
) == REAL_CST
9078 && TREE_CODE (arg0
) == MINUS_EXPR
9079 && TREE_CODE (TREE_OPERAND (arg0
, 0)) == REAL_CST
9080 && 0 != (tem
= const_binop (MINUS_EXPR
, TREE_OPERAND (arg0
, 0),
9082 && ! TREE_CONSTANT_OVERFLOW (tem
))
9083 return fold_build2 (swap_tree_comparison (code
), type
,
9084 TREE_OPERAND (arg0
, 1), tem
);
9086 /* Fold comparisons against built-in math functions. */
9087 if (TREE_CODE (arg1
) == REAL_CST
9088 && flag_unsafe_math_optimizations
9089 && ! flag_errno_math
)
9091 enum built_in_function fcode
= builtin_mathfn_code (arg0
);
9093 if (fcode
!= END_BUILTINS
)
9095 tem
= fold_mathfn_compare (fcode
, code
, type
, arg0
, arg1
);
9096 if (tem
!= NULL_TREE
)
9102 /* Convert foo++ == CONST into ++foo == CONST + INCR. */
9103 if (TREE_CONSTANT (arg1
)
9104 && (TREE_CODE (arg0
) == POSTINCREMENT_EXPR
9105 || TREE_CODE (arg0
) == POSTDECREMENT_EXPR
)
9106 /* This optimization is invalid for ordered comparisons
9107 if CONST+INCR overflows or if foo+incr might overflow.
9108 This optimization is invalid for floating point due to rounding.
9109 For pointer types we assume overflow doesn't happen. */
9110 && (POINTER_TYPE_P (TREE_TYPE (arg0
))
9111 || (INTEGRAL_TYPE_P (TREE_TYPE (arg0
))
9112 && (code
== EQ_EXPR
|| code
== NE_EXPR
))))
9114 tree varop
, newconst
;
9116 if (TREE_CODE (arg0
) == POSTINCREMENT_EXPR
)
9118 newconst
= fold_build2 (PLUS_EXPR
, TREE_TYPE (arg0
),
9119 arg1
, TREE_OPERAND (arg0
, 1));
9120 varop
= build2 (PREINCREMENT_EXPR
, TREE_TYPE (arg0
),
9121 TREE_OPERAND (arg0
, 0),
9122 TREE_OPERAND (arg0
, 1));
9126 newconst
= fold_build2 (MINUS_EXPR
, TREE_TYPE (arg0
),
9127 arg1
, TREE_OPERAND (arg0
, 1));
9128 varop
= build2 (PREDECREMENT_EXPR
, TREE_TYPE (arg0
),
9129 TREE_OPERAND (arg0
, 0),
9130 TREE_OPERAND (arg0
, 1));
9134 /* If VAROP is a reference to a bitfield, we must mask
9135 the constant by the width of the field. */
9136 if (TREE_CODE (TREE_OPERAND (varop
, 0)) == COMPONENT_REF
9137 && DECL_BIT_FIELD (TREE_OPERAND (TREE_OPERAND (varop
, 0), 1))
9138 && host_integerp (DECL_SIZE (TREE_OPERAND
9139 (TREE_OPERAND (varop
, 0), 1)), 1))
9141 tree fielddecl
= TREE_OPERAND (TREE_OPERAND (varop
, 0), 1);
9142 HOST_WIDE_INT size
= tree_low_cst (DECL_SIZE (fielddecl
), 1);
9143 tree folded_compare
, shift
;
9145 /* First check whether the comparison would come out
9146 always the same. If we don't do that we would
9147 change the meaning with the masking. */
9148 folded_compare
= fold_build2 (code
, type
,
9149 TREE_OPERAND (varop
, 0), arg1
);
9150 if (integer_zerop (folded_compare
)
9151 || integer_onep (folded_compare
))
9152 return omit_one_operand (type
, folded_compare
, varop
);
9154 shift
= build_int_cst (NULL_TREE
,
9155 TYPE_PRECISION (TREE_TYPE (varop
)) - size
);
9156 shift
= fold_convert (TREE_TYPE (varop
), shift
);
9157 newconst
= fold_build2 (LSHIFT_EXPR
, TREE_TYPE (varop
),
9159 newconst
= fold_build2 (RSHIFT_EXPR
, TREE_TYPE (varop
),
9163 return fold_build2 (code
, type
, varop
, newconst
);
9166 /* Change X >= C to X > (C - 1) and X < C to X <= (C - 1) if C > 0.
9167 This transformation affects the cases which are handled in later
9168 optimizations involving comparisons with non-negative constants. */
9169 if (TREE_CODE (arg1
) == INTEGER_CST
9170 && TREE_CODE (arg0
) != INTEGER_CST
9171 && tree_int_cst_sgn (arg1
) > 0)
9176 arg1
= const_binop (MINUS_EXPR
, arg1
, integer_one_node
, 0);
9177 return fold_build2 (GT_EXPR
, type
, arg0
, arg1
);
9180 arg1
= const_binop (MINUS_EXPR
, arg1
, integer_one_node
, 0);
9181 return fold_build2 (LE_EXPR
, type
, arg0
, arg1
);
9188 /* Comparisons with the highest or lowest possible integer of
9189 the specified size will have known values. */
9191 int width
= GET_MODE_BITSIZE (TYPE_MODE (TREE_TYPE (arg1
)));
9193 if (TREE_CODE (arg1
) == INTEGER_CST
9194 && ! TREE_CONSTANT_OVERFLOW (arg1
)
9195 && width
<= 2 * HOST_BITS_PER_WIDE_INT
9196 && (INTEGRAL_TYPE_P (TREE_TYPE (arg1
))
9197 || POINTER_TYPE_P (TREE_TYPE (arg1
))))
9199 HOST_WIDE_INT signed_max_hi
;
9200 unsigned HOST_WIDE_INT signed_max_lo
;
9201 unsigned HOST_WIDE_INT max_hi
, max_lo
, min_hi
, min_lo
;
9203 if (width
<= HOST_BITS_PER_WIDE_INT
)
9205 signed_max_lo
= ((unsigned HOST_WIDE_INT
) 1 << (width
- 1))
9210 if (TYPE_UNSIGNED (TREE_TYPE (arg1
)))
9212 max_lo
= ((unsigned HOST_WIDE_INT
) 2 << (width
- 1)) - 1;
9218 max_lo
= signed_max_lo
;
9219 min_lo
= ((unsigned HOST_WIDE_INT
) -1 << (width
- 1));
9225 width
-= HOST_BITS_PER_WIDE_INT
;
9227 signed_max_hi
= ((unsigned HOST_WIDE_INT
) 1 << (width
- 1))
9232 if (TYPE_UNSIGNED (TREE_TYPE (arg1
)))
9234 max_hi
= ((unsigned HOST_WIDE_INT
) 2 << (width
- 1)) - 1;
9239 max_hi
= signed_max_hi
;
9240 min_hi
= ((unsigned HOST_WIDE_INT
) -1 << (width
- 1));
9244 if ((unsigned HOST_WIDE_INT
) TREE_INT_CST_HIGH (arg1
) == max_hi
9245 && TREE_INT_CST_LOW (arg1
) == max_lo
)
9249 return omit_one_operand (type
, integer_zero_node
, arg0
);
9252 return fold_build2 (EQ_EXPR
, type
, arg0
, arg1
);
9255 return omit_one_operand (type
, integer_one_node
, arg0
);
9258 return fold_build2 (NE_EXPR
, type
, arg0
, arg1
);
9260 /* The GE_EXPR and LT_EXPR cases above are not normally
9261 reached because of previous transformations. */
9266 else if ((unsigned HOST_WIDE_INT
) TREE_INT_CST_HIGH (arg1
)
9268 && TREE_INT_CST_LOW (arg1
) == max_lo
- 1)
9272 arg1
= const_binop (PLUS_EXPR
, arg1
, integer_one_node
, 0);
9273 return fold_build2 (EQ_EXPR
, type
, arg0
, arg1
);
9275 arg1
= const_binop (PLUS_EXPR
, arg1
, integer_one_node
, 0);
9276 return fold_build2 (NE_EXPR
, type
, arg0
, arg1
);
9280 else if ((unsigned HOST_WIDE_INT
) TREE_INT_CST_HIGH (arg1
)
9282 && TREE_INT_CST_LOW (arg1
) == min_lo
)
9286 return omit_one_operand (type
, integer_zero_node
, arg0
);
9289 return fold_build2 (EQ_EXPR
, type
, arg0
, arg1
);
9292 return omit_one_operand (type
, integer_one_node
, arg0
);
9295 return fold_build2 (NE_EXPR
, type
, arg0
, arg1
);
9300 else if ((unsigned HOST_WIDE_INT
) TREE_INT_CST_HIGH (arg1
)
9302 && TREE_INT_CST_LOW (arg1
) == min_lo
+ 1)
9306 arg1
= const_binop (MINUS_EXPR
, arg1
, integer_one_node
, 0);
9307 return fold_build2 (NE_EXPR
, type
, arg0
, arg1
);
9309 arg1
= const_binop (MINUS_EXPR
, arg1
, integer_one_node
, 0);
9310 return fold_build2 (EQ_EXPR
, type
, arg0
, arg1
);
9315 else if (!in_gimple_form
9316 && TREE_INT_CST_HIGH (arg1
) == signed_max_hi
9317 && TREE_INT_CST_LOW (arg1
) == signed_max_lo
9318 && TYPE_UNSIGNED (TREE_TYPE (arg1
))
9319 /* signed_type does not work on pointer types. */
9320 && INTEGRAL_TYPE_P (TREE_TYPE (arg1
)))
9322 /* The following case also applies to X < signed_max+1
9323 and X >= signed_max+1 because previous transformations. */
9324 if (code
== LE_EXPR
|| code
== GT_EXPR
)
9327 st0
= lang_hooks
.types
.signed_type (TREE_TYPE (arg0
));
9328 st1
= lang_hooks
.types
.signed_type (TREE_TYPE (arg1
));
9330 (build2 (code
== LE_EXPR
? GE_EXPR
: LT_EXPR
,
9331 type
, fold_convert (st0
, arg0
),
9332 fold_convert (st1
, integer_zero_node
)));
9338 /* If this is an EQ or NE comparison of a constant with a PLUS_EXPR or
9339 a MINUS_EXPR of a constant, we can convert it into a comparison with
9340 a revised constant as long as no overflow occurs. */
9341 if ((code
== EQ_EXPR
|| code
== NE_EXPR
)
9342 && TREE_CODE (arg1
) == INTEGER_CST
9343 && (TREE_CODE (arg0
) == PLUS_EXPR
9344 || TREE_CODE (arg0
) == MINUS_EXPR
)
9345 && TREE_CODE (TREE_OPERAND (arg0
, 1)) == INTEGER_CST
9346 && 0 != (tem
= const_binop (TREE_CODE (arg0
) == PLUS_EXPR
9347 ? MINUS_EXPR
: PLUS_EXPR
,
9348 arg1
, TREE_OPERAND (arg0
, 1), 0))
9349 && ! TREE_CONSTANT_OVERFLOW (tem
))
9350 return fold_build2 (code
, type
, TREE_OPERAND (arg0
, 0), tem
);
9352 /* Similarly for a NEGATE_EXPR. */
9353 else if ((code
== EQ_EXPR
|| code
== NE_EXPR
)
9354 && TREE_CODE (arg0
) == NEGATE_EXPR
9355 && TREE_CODE (arg1
) == INTEGER_CST
9356 && 0 != (tem
= negate_expr (arg1
))
9357 && TREE_CODE (tem
) == INTEGER_CST
9358 && ! TREE_CONSTANT_OVERFLOW (tem
))
9359 return fold_build2 (code
, type
, TREE_OPERAND (arg0
, 0), tem
);
9361 /* If we have X - Y == 0, we can convert that to X == Y and similarly
9362 for !=. Don't do this for ordered comparisons due to overflow. */
9363 else if ((code
== NE_EXPR
|| code
== EQ_EXPR
)
9364 && integer_zerop (arg1
) && TREE_CODE (arg0
) == MINUS_EXPR
)
9365 return fold_build2 (code
, type
,
9366 TREE_OPERAND (arg0
, 0), TREE_OPERAND (arg0
, 1));
9368 else if (TREE_CODE (TREE_TYPE (arg0
)) == INTEGER_TYPE
9369 && (TREE_CODE (arg0
) == NOP_EXPR
9370 || TREE_CODE (arg0
) == CONVERT_EXPR
))
9372 /* If we are widening one operand of an integer comparison,
9373 see if the other operand is similarly being widened. Perhaps we
9374 can do the comparison in the narrower type. */
9375 tem
= fold_widened_comparison (code
, type
, arg0
, arg1
);
9379 /* Or if we are changing signedness. */
9380 tem
= fold_sign_changed_comparison (code
, type
, arg0
, arg1
);
9385 /* If this is comparing a constant with a MIN_EXPR or a MAX_EXPR of a
9386 constant, we can simplify it. */
9387 else if (TREE_CODE (arg1
) == INTEGER_CST
9388 && (TREE_CODE (arg0
) == MIN_EXPR
9389 || TREE_CODE (arg0
) == MAX_EXPR
)
9390 && TREE_CODE (TREE_OPERAND (arg0
, 1)) == INTEGER_CST
)
9392 tem
= optimize_minmax_comparison (code
, type
, op0
, op1
);
9399 /* If we are comparing an ABS_EXPR with a constant, we can
9400 convert all the cases into explicit comparisons, but they may
9401 well not be faster than doing the ABS and one comparison.
9402 But ABS (X) <= C is a range comparison, which becomes a subtraction
9403 and a comparison, and is probably faster. */
9404 else if (code
== LE_EXPR
&& TREE_CODE (arg1
) == INTEGER_CST
9405 && TREE_CODE (arg0
) == ABS_EXPR
9406 && ! TREE_SIDE_EFFECTS (arg0
)
9407 && (0 != (tem
= negate_expr (arg1
)))
9408 && TREE_CODE (tem
) == INTEGER_CST
9409 && ! TREE_CONSTANT_OVERFLOW (tem
))
9410 return fold_build2 (TRUTH_ANDIF_EXPR
, type
,
9411 build2 (GE_EXPR
, type
,
9412 TREE_OPERAND (arg0
, 0), tem
),
9413 build2 (LE_EXPR
, type
,
9414 TREE_OPERAND (arg0
, 0), arg1
));
9416 /* Convert ABS_EXPR<x> >= 0 to true. */
9417 else if (code
== GE_EXPR
9418 && tree_expr_nonnegative_p (arg0
)
9419 && (integer_zerop (arg1
)
9420 || (! HONOR_NANS (TYPE_MODE (TREE_TYPE (arg0
)))
9421 && real_zerop (arg1
))))
9422 return omit_one_operand (type
, integer_one_node
, arg0
);
9424 /* Convert ABS_EXPR<x> < 0 to false. */
9425 else if (code
== LT_EXPR
9426 && tree_expr_nonnegative_p (arg0
)
9427 && (integer_zerop (arg1
) || real_zerop (arg1
)))
9428 return omit_one_operand (type
, integer_zero_node
, arg0
);
9430 /* Convert ABS_EXPR<x> == 0 or ABS_EXPR<x> != 0 to x == 0 or x != 0. */
9431 else if ((code
== EQ_EXPR
|| code
== NE_EXPR
)
9432 && TREE_CODE (arg0
) == ABS_EXPR
9433 && (integer_zerop (arg1
) || real_zerop (arg1
)))
9434 return fold_build2 (code
, type
, TREE_OPERAND (arg0
, 0), arg1
);
9436 /* If this is an EQ or NE comparison with zero and ARG0 is
9437 (1 << foo) & bar, convert it to (bar >> foo) & 1. Both require
9438 two operations, but the latter can be done in one less insn
9439 on machines that have only two-operand insns or on which a
9440 constant cannot be the first operand. */
9441 if (integer_zerop (arg1
) && (code
== EQ_EXPR
|| code
== NE_EXPR
)
9442 && TREE_CODE (arg0
) == BIT_AND_EXPR
)
9444 tree arg00
= TREE_OPERAND (arg0
, 0);
9445 tree arg01
= TREE_OPERAND (arg0
, 1);
9446 if (TREE_CODE (arg00
) == LSHIFT_EXPR
9447 && integer_onep (TREE_OPERAND (arg00
, 0)))
9449 fold_build2 (code
, type
,
9450 build2 (BIT_AND_EXPR
, TREE_TYPE (arg0
),
9451 build2 (RSHIFT_EXPR
, TREE_TYPE (arg00
),
9452 arg01
, TREE_OPERAND (arg00
, 1)),
9453 fold_convert (TREE_TYPE (arg0
),
9456 else if (TREE_CODE (TREE_OPERAND (arg0
, 1)) == LSHIFT_EXPR
9457 && integer_onep (TREE_OPERAND (TREE_OPERAND (arg0
, 1), 0)))
9459 fold_build2 (code
, type
,
9460 build2 (BIT_AND_EXPR
, TREE_TYPE (arg0
),
9461 build2 (RSHIFT_EXPR
, TREE_TYPE (arg01
),
9462 arg00
, TREE_OPERAND (arg01
, 1)),
9463 fold_convert (TREE_TYPE (arg0
),
9468 /* If this is an NE or EQ comparison of zero against the result of a
9469 signed MOD operation whose second operand is a power of 2, make
9470 the MOD operation unsigned since it is simpler and equivalent. */
9471 if ((code
== NE_EXPR
|| code
== EQ_EXPR
)
9472 && integer_zerop (arg1
)
9473 && !TYPE_UNSIGNED (TREE_TYPE (arg0
))
9474 && (TREE_CODE (arg0
) == TRUNC_MOD_EXPR
9475 || TREE_CODE (arg0
) == CEIL_MOD_EXPR
9476 || TREE_CODE (arg0
) == FLOOR_MOD_EXPR
9477 || TREE_CODE (arg0
) == ROUND_MOD_EXPR
)
9478 && integer_pow2p (TREE_OPERAND (arg0
, 1)))
9480 tree newtype
= lang_hooks
.types
.unsigned_type (TREE_TYPE (arg0
));
9481 tree newmod
= fold_build2 (TREE_CODE (arg0
), newtype
,
9482 fold_convert (newtype
,
9483 TREE_OPERAND (arg0
, 0)),
9484 fold_convert (newtype
,
9485 TREE_OPERAND (arg0
, 1)));
9487 return fold_build2 (code
, type
, newmod
,
9488 fold_convert (newtype
, arg1
));
9491 /* If this is an NE comparison of zero with an AND of one, remove the
9492 comparison since the AND will give the correct value. */
9493 if (code
== NE_EXPR
&& integer_zerop (arg1
)
9494 && TREE_CODE (arg0
) == BIT_AND_EXPR
9495 && integer_onep (TREE_OPERAND (arg0
, 1)))
9496 return fold_convert (type
, arg0
);
9498 /* If we have (A & C) == C where C is a power of 2, convert this into
9499 (A & C) != 0. Similarly for NE_EXPR. */
9500 if ((code
== EQ_EXPR
|| code
== NE_EXPR
)
9501 && TREE_CODE (arg0
) == BIT_AND_EXPR
9502 && integer_pow2p (TREE_OPERAND (arg0
, 1))
9503 && operand_equal_p (TREE_OPERAND (arg0
, 1), arg1
, 0))
9504 return fold_build2 (code
== EQ_EXPR
? NE_EXPR
: EQ_EXPR
, type
,
9505 arg0
, fold_convert (TREE_TYPE (arg0
),
9506 integer_zero_node
));
9508 /* If we have (A & C) != 0 or (A & C) == 0 and C is the sign
9509 bit, then fold the expression into A < 0 or A >= 0. */
9510 tem
= fold_single_bit_test_into_sign_test (code
, arg0
, arg1
, type
);
9514 /* If we have (A & C) == D where D & ~C != 0, convert this into 0.
9515 Similarly for NE_EXPR. */
9516 if ((code
== EQ_EXPR
|| code
== NE_EXPR
)
9517 && TREE_CODE (arg0
) == BIT_AND_EXPR
9518 && TREE_CODE (arg1
) == INTEGER_CST
9519 && TREE_CODE (TREE_OPERAND (arg0
, 1)) == INTEGER_CST
)
9521 tree notc
= fold_build1 (BIT_NOT_EXPR
,
9522 TREE_TYPE (TREE_OPERAND (arg0
, 1)),
9523 TREE_OPERAND (arg0
, 1));
9524 tree dandnotc
= fold_build2 (BIT_AND_EXPR
, TREE_TYPE (arg0
),
9526 tree rslt
= code
== EQ_EXPR
? integer_zero_node
: integer_one_node
;
9527 if (integer_nonzerop (dandnotc
))
9528 return omit_one_operand (type
, rslt
, arg0
);
9531 /* If we have (A | C) == D where C & ~D != 0, convert this into 0.
9532 Similarly for NE_EXPR. */
9533 if ((code
== EQ_EXPR
|| code
== NE_EXPR
)
9534 && TREE_CODE (arg0
) == BIT_IOR_EXPR
9535 && TREE_CODE (arg1
) == INTEGER_CST
9536 && TREE_CODE (TREE_OPERAND (arg0
, 1)) == INTEGER_CST
)
9538 tree notd
= fold_build1 (BIT_NOT_EXPR
, TREE_TYPE (arg1
), arg1
);
9539 tree candnotd
= fold_build2 (BIT_AND_EXPR
, TREE_TYPE (arg0
),
9540 TREE_OPERAND (arg0
, 1), notd
);
9541 tree rslt
= code
== EQ_EXPR
? integer_zero_node
: integer_one_node
;
9542 if (integer_nonzerop (candnotd
))
9543 return omit_one_operand (type
, rslt
, arg0
);
9546 /* If X is unsigned, convert X < (1 << Y) into X >> Y == 0
9547 and similarly for >= into !=. */
9548 if ((code
== LT_EXPR
|| code
== GE_EXPR
)
9549 && TYPE_UNSIGNED (TREE_TYPE (arg0
))
9550 && TREE_CODE (arg1
) == LSHIFT_EXPR
9551 && integer_onep (TREE_OPERAND (arg1
, 0)))
9552 return build2 (code
== LT_EXPR
? EQ_EXPR
: NE_EXPR
, type
,
9553 build2 (RSHIFT_EXPR
, TREE_TYPE (arg0
), arg0
,
9554 TREE_OPERAND (arg1
, 1)),
9555 fold_convert (TREE_TYPE (arg0
), integer_zero_node
));
9557 else if ((code
== LT_EXPR
|| code
== GE_EXPR
)
9558 && TYPE_UNSIGNED (TREE_TYPE (arg0
))
9559 && (TREE_CODE (arg1
) == NOP_EXPR
9560 || TREE_CODE (arg1
) == CONVERT_EXPR
)
9561 && TREE_CODE (TREE_OPERAND (arg1
, 0)) == LSHIFT_EXPR
9562 && integer_onep (TREE_OPERAND (TREE_OPERAND (arg1
, 0), 0)))
9564 build2 (code
== LT_EXPR
? EQ_EXPR
: NE_EXPR
, type
,
9565 fold_convert (TREE_TYPE (arg0
),
9566 build2 (RSHIFT_EXPR
, TREE_TYPE (arg0
), arg0
,
9567 TREE_OPERAND (TREE_OPERAND (arg1
, 0),
9569 fold_convert (TREE_TYPE (arg0
), integer_zero_node
));
9571 /* Simplify comparison of something with itself. (For IEEE
9572 floating-point, we can only do some of these simplifications.) */
9573 if (operand_equal_p (arg0
, arg1
, 0))
9578 if (! FLOAT_TYPE_P (TREE_TYPE (arg0
))
9579 || ! HONOR_NANS (TYPE_MODE (TREE_TYPE (arg0
))))
9580 return constant_boolean_node (1, type
);
9585 if (! FLOAT_TYPE_P (TREE_TYPE (arg0
))
9586 || ! HONOR_NANS (TYPE_MODE (TREE_TYPE (arg0
))))
9587 return constant_boolean_node (1, type
);
9588 return fold_build2 (EQ_EXPR
, type
, arg0
, arg1
);
9591 /* For NE, we can only do this simplification if integer
9592 or we don't honor IEEE floating point NaNs. */
9593 if (FLOAT_TYPE_P (TREE_TYPE (arg0
))
9594 && HONOR_NANS (TYPE_MODE (TREE_TYPE (arg0
))))
9596 /* ... fall through ... */
9599 return constant_boolean_node (0, type
);
9605 /* If we are comparing an expression that just has comparisons
9606 of two integer values, arithmetic expressions of those comparisons,
9607 and constants, we can simplify it. There are only three cases
9608 to check: the two values can either be equal, the first can be
9609 greater, or the second can be greater. Fold the expression for
9610 those three values. Since each value must be 0 or 1, we have
9611 eight possibilities, each of which corresponds to the constant 0
9612 or 1 or one of the six possible comparisons.
9614 This handles common cases like (a > b) == 0 but also handles
9615 expressions like ((x > y) - (y > x)) > 0, which supposedly
9616 occur in macroized code. */
9618 if (TREE_CODE (arg1
) == INTEGER_CST
&& TREE_CODE (arg0
) != INTEGER_CST
)
9620 tree cval1
= 0, cval2
= 0;
9623 if (twoval_comparison_p (arg0
, &cval1
, &cval2
, &save_p
)
9624 /* Don't handle degenerate cases here; they should already
9625 have been handled anyway. */
9626 && cval1
!= 0 && cval2
!= 0
9627 && ! (TREE_CONSTANT (cval1
) && TREE_CONSTANT (cval2
))
9628 && TREE_TYPE (cval1
) == TREE_TYPE (cval2
)
9629 && INTEGRAL_TYPE_P (TREE_TYPE (cval1
))
9630 && TYPE_MAX_VALUE (TREE_TYPE (cval1
))
9631 && TYPE_MAX_VALUE (TREE_TYPE (cval2
))
9632 && ! operand_equal_p (TYPE_MIN_VALUE (TREE_TYPE (cval1
)),
9633 TYPE_MAX_VALUE (TREE_TYPE (cval2
)), 0))
9635 tree maxval
= TYPE_MAX_VALUE (TREE_TYPE (cval1
));
9636 tree minval
= TYPE_MIN_VALUE (TREE_TYPE (cval1
));
9638 /* We can't just pass T to eval_subst in case cval1 or cval2
9639 was the same as ARG1. */
9642 = fold_build2 (code
, type
,
9643 eval_subst (arg0
, cval1
, maxval
,
9647 = fold_build2 (code
, type
,
9648 eval_subst (arg0
, cval1
, maxval
,
9652 = fold_build2 (code
, type
,
9653 eval_subst (arg0
, cval1
, minval
,
9657 /* All three of these results should be 0 or 1. Confirm they
9658 are. Then use those values to select the proper code
9661 if ((integer_zerop (high_result
)
9662 || integer_onep (high_result
))
9663 && (integer_zerop (equal_result
)
9664 || integer_onep (equal_result
))
9665 && (integer_zerop (low_result
)
9666 || integer_onep (low_result
)))
9668 /* Make a 3-bit mask with the high-order bit being the
9669 value for `>', the next for '=', and the low for '<'. */
9670 switch ((integer_onep (high_result
) * 4)
9671 + (integer_onep (equal_result
) * 2)
9672 + integer_onep (low_result
))
9676 return omit_one_operand (type
, integer_zero_node
, arg0
);
9697 return omit_one_operand (type
, integer_one_node
, arg0
);
9701 return save_expr (build2 (code
, type
, cval1
, cval2
));
9703 return fold_build2 (code
, type
, cval1
, cval2
);
9708 /* If this is a comparison of a field, we may be able to simplify it. */
9709 if (((TREE_CODE (arg0
) == COMPONENT_REF
9710 && lang_hooks
.can_use_bit_fields_p ())
9711 || TREE_CODE (arg0
) == BIT_FIELD_REF
)
9712 && (code
== EQ_EXPR
|| code
== NE_EXPR
)
9713 /* Handle the constant case even without -O
9714 to make sure the warnings are given. */
9715 && (optimize
|| TREE_CODE (arg1
) == INTEGER_CST
))
9717 t1
= optimize_bit_field_compare (code
, type
, arg0
, arg1
);
9722 /* Fold a comparison of the address of COMPONENT_REFs with the same
9723 type and component to a comparison of the address of the base
9724 object. In short, &x->a OP &y->a to x OP y and
9725 &x->a OP &y.a to x OP &y */
9726 if (TREE_CODE (arg0
) == ADDR_EXPR
9727 && TREE_CODE (TREE_OPERAND (arg0
, 0)) == COMPONENT_REF
9728 && TREE_CODE (arg1
) == ADDR_EXPR
9729 && TREE_CODE (TREE_OPERAND (arg1
, 0)) == COMPONENT_REF
)
9731 tree cref0
= TREE_OPERAND (arg0
, 0);
9732 tree cref1
= TREE_OPERAND (arg1
, 0);
9733 if (TREE_OPERAND (cref0
, 1) == TREE_OPERAND (cref1
, 1))
9735 tree op0
= TREE_OPERAND (cref0
, 0);
9736 tree op1
= TREE_OPERAND (cref1
, 0);
9737 return fold_build2 (code
, type
,
9738 build_fold_addr_expr (op0
),
9739 build_fold_addr_expr (op1
));
9743 /* If this is a comparison of complex values and either or both sides
9744 are a COMPLEX_EXPR or COMPLEX_CST, it is best to split up the
9745 comparisons and join them with a TRUTH_ANDIF_EXPR or TRUTH_ORIF_EXPR.
9746 This may prevent needless evaluations. */
9747 if ((code
== EQ_EXPR
|| code
== NE_EXPR
)
9748 && TREE_CODE (TREE_TYPE (arg0
)) == COMPLEX_TYPE
9749 && (TREE_CODE (arg0
) == COMPLEX_EXPR
9750 || TREE_CODE (arg1
) == COMPLEX_EXPR
9751 || TREE_CODE (arg0
) == COMPLEX_CST
9752 || TREE_CODE (arg1
) == COMPLEX_CST
))
9754 tree subtype
= TREE_TYPE (TREE_TYPE (arg0
));
9755 tree real0
, imag0
, real1
, imag1
;
9757 arg0
= save_expr (arg0
);
9758 arg1
= save_expr (arg1
);
9759 real0
= fold_build1 (REALPART_EXPR
, subtype
, arg0
);
9760 imag0
= fold_build1 (IMAGPART_EXPR
, subtype
, arg0
);
9761 real1
= fold_build1 (REALPART_EXPR
, subtype
, arg1
);
9762 imag1
= fold_build1 (IMAGPART_EXPR
, subtype
, arg1
);
9764 return fold_build2 ((code
== EQ_EXPR
? TRUTH_ANDIF_EXPR
9767 fold_build2 (code
, type
, real0
, real1
),
9768 fold_build2 (code
, type
, imag0
, imag1
));
9771 /* Optimize comparisons of strlen vs zero to a compare of the
9772 first character of the string vs zero. To wit,
9773 strlen(ptr) == 0 => *ptr == 0
9774 strlen(ptr) != 0 => *ptr != 0
9775 Other cases should reduce to one of these two (or a constant)
9776 due to the return value of strlen being unsigned. */
9777 if ((code
== EQ_EXPR
|| code
== NE_EXPR
)
9778 && integer_zerop (arg1
)
9779 && TREE_CODE (arg0
) == CALL_EXPR
)
9781 tree fndecl
= get_callee_fndecl (arg0
);
9785 && DECL_BUILT_IN_CLASS (fndecl
) == BUILT_IN_NORMAL
9786 && DECL_FUNCTION_CODE (fndecl
) == BUILT_IN_STRLEN
9787 && (arglist
= TREE_OPERAND (arg0
, 1))
9788 && TREE_CODE (TREE_TYPE (TREE_VALUE (arglist
))) == POINTER_TYPE
9789 && ! TREE_CHAIN (arglist
))
9790 return fold_build2 (code
, type
,
9791 build1 (INDIRECT_REF
, char_type_node
,
9792 TREE_VALUE (arglist
)),
9793 fold_convert (char_type_node
,
9794 integer_zero_node
));
9797 /* We can fold X/C1 op C2 where C1 and C2 are integer constants
9798 into a single range test. */
9799 if ((TREE_CODE (arg0
) == TRUNC_DIV_EXPR
9800 || TREE_CODE (arg0
) == EXACT_DIV_EXPR
)
9801 && TREE_CODE (arg1
) == INTEGER_CST
9802 && TREE_CODE (TREE_OPERAND (arg0
, 1)) == INTEGER_CST
9803 && !integer_zerop (TREE_OPERAND (arg0
, 1))
9804 && !TREE_OVERFLOW (TREE_OPERAND (arg0
, 1))
9805 && !TREE_OVERFLOW (arg1
))
9807 t1
= fold_div_compare (code
, type
, arg0
, arg1
);
9808 if (t1
!= NULL_TREE
)
9812 if ((code
== EQ_EXPR
|| code
== NE_EXPR
)
9813 && !TREE_SIDE_EFFECTS (arg0
)
9814 && integer_zerop (arg1
)
9815 && tree_expr_nonzero_p (arg0
))
9816 return constant_boolean_node (code
==NE_EXPR
, type
);
9818 t1
= fold_relational_const (code
, type
, arg0
, arg1
);
9819 return t1
== NULL_TREE
? NULL_TREE
: t1
;
9821 case UNORDERED_EXPR
:
9829 if (TREE_CODE (arg0
) == REAL_CST
&& TREE_CODE (arg1
) == REAL_CST
)
9831 t1
= fold_relational_const (code
, type
, arg0
, arg1
);
9832 if (t1
!= NULL_TREE
)
9836 /* If the first operand is NaN, the result is constant. */
9837 if (TREE_CODE (arg0
) == REAL_CST
9838 && REAL_VALUE_ISNAN (TREE_REAL_CST (arg0
))
9839 && (code
!= LTGT_EXPR
|| ! flag_trapping_math
))
9841 t1
= (code
== ORDERED_EXPR
|| code
== LTGT_EXPR
)
9844 return omit_one_operand (type
, t1
, arg1
);
9847 /* If the second operand is NaN, the result is constant. */
9848 if (TREE_CODE (arg1
) == REAL_CST
9849 && REAL_VALUE_ISNAN (TREE_REAL_CST (arg1
))
9850 && (code
!= LTGT_EXPR
|| ! flag_trapping_math
))
9852 t1
= (code
== ORDERED_EXPR
|| code
== LTGT_EXPR
)
9855 return omit_one_operand (type
, t1
, arg0
);
9858 /* Simplify unordered comparison of something with itself. */
9859 if ((code
== UNLE_EXPR
|| code
== UNGE_EXPR
|| code
== UNEQ_EXPR
)
9860 && operand_equal_p (arg0
, arg1
, 0))
9861 return constant_boolean_node (1, type
);
9863 if (code
== LTGT_EXPR
9864 && !flag_trapping_math
9865 && operand_equal_p (arg0
, arg1
, 0))
9866 return constant_boolean_node (0, type
);
9868 /* Fold (double)float1 CMP (double)float2 into float1 CMP float2. */
9870 tree targ0
= strip_float_extensions (arg0
);
9871 tree targ1
= strip_float_extensions (arg1
);
9872 tree newtype
= TREE_TYPE (targ0
);
9874 if (TYPE_PRECISION (TREE_TYPE (targ1
)) > TYPE_PRECISION (newtype
))
9875 newtype
= TREE_TYPE (targ1
);
9877 if (TYPE_PRECISION (newtype
) < TYPE_PRECISION (TREE_TYPE (arg0
)))
9878 return fold_build2 (code
, type
, fold_convert (newtype
, targ0
),
9879 fold_convert (newtype
, targ1
));
9885 /* When pedantic, a compound expression can be neither an lvalue
9886 nor an integer constant expression. */
9887 if (TREE_SIDE_EFFECTS (arg0
) || TREE_CONSTANT (arg1
))
9889 /* Don't let (0, 0) be null pointer constant. */
9890 tem
= integer_zerop (arg1
) ? build1 (NOP_EXPR
, type
, arg1
)
9891 : fold_convert (type
, arg1
);
9892 return pedantic_non_lvalue (tem
);
9896 return build_complex (type
, arg0
, arg1
);
9900 /* An ASSERT_EXPR should never be passed to fold_binary. */
9905 } /* switch (code) */
9908 /* Fold a ternary expression of code CODE and type TYPE with operands
9909 OP0, OP1, and OP2. Return the folded expression if folding is
9910 successful. Otherwise, return NULL_TREE. */
9913 fold_ternary (enum tree_code code
, tree type
, tree op0
, tree op1
, tree op2
)
9916 tree arg0
= NULL_TREE
, arg1
= NULL_TREE
;
9917 enum tree_code_class kind
= TREE_CODE_CLASS (code
);
9919 gcc_assert (IS_EXPR_CODE_CLASS (kind
)
9920 && TREE_CODE_LENGTH (code
) == 3);
9922 /* Strip any conversions that don't change the mode. This is safe
9923 for every expression, except for a comparison expression because
9924 its signedness is derived from its operands. So, in the latter
9925 case, only strip conversions that don't change the signedness.
9927 Note that this is done as an internal manipulation within the
9928 constant folder, in order to find the simplest representation of
9929 the arguments so that their form can be studied. In any cases,
9930 the appropriate type conversions should be put back in the tree
9931 that will get out of the constant folder. */
9947 if (TREE_CODE (arg0
) == CONSTRUCTOR
9948 && ! type_contains_placeholder_p (TREE_TYPE (arg0
)))
9950 tree m
= purpose_member (arg1
, CONSTRUCTOR_ELTS (arg0
));
9952 return TREE_VALUE (m
);
9957 /* Pedantic ANSI C says that a conditional expression is never an lvalue,
9958 so all simple results must be passed through pedantic_non_lvalue. */
9959 if (TREE_CODE (arg0
) == INTEGER_CST
)
9961 tem
= integer_zerop (arg0
) ? op2
: op1
;
9962 /* Only optimize constant conditions when the selected branch
9963 has the same type as the COND_EXPR. This avoids optimizing
9964 away "c ? x : throw", where the throw has a void type. */
9965 if (! VOID_TYPE_P (TREE_TYPE (tem
))
9966 || VOID_TYPE_P (type
))
9967 return pedantic_non_lvalue (tem
);
9970 if (operand_equal_p (arg1
, op2
, 0))
9971 return pedantic_omit_one_operand (type
, arg1
, arg0
);
9973 /* If we have A op B ? A : C, we may be able to convert this to a
9974 simpler expression, depending on the operation and the values
9975 of B and C. Signed zeros prevent all of these transformations,
9976 for reasons given above each one.
9978 Also try swapping the arguments and inverting the conditional. */
9979 if (COMPARISON_CLASS_P (arg0
)
9980 && operand_equal_for_comparison_p (TREE_OPERAND (arg0
, 0),
9981 arg1
, TREE_OPERAND (arg0
, 1))
9982 && !HONOR_SIGNED_ZEROS (TYPE_MODE (TREE_TYPE (arg1
))))
9984 tem
= fold_cond_expr_with_comparison (type
, arg0
, op1
, op2
);
9989 if (COMPARISON_CLASS_P (arg0
)
9990 && operand_equal_for_comparison_p (TREE_OPERAND (arg0
, 0),
9992 TREE_OPERAND (arg0
, 1))
9993 && !HONOR_SIGNED_ZEROS (TYPE_MODE (TREE_TYPE (op2
))))
9995 tem
= invert_truthvalue (arg0
);
9996 if (COMPARISON_CLASS_P (tem
))
9998 tem
= fold_cond_expr_with_comparison (type
, tem
, op2
, op1
);
10004 /* If the second operand is simpler than the third, swap them
10005 since that produces better jump optimization results. */
10006 if (tree_swap_operands_p (op1
, op2
, false))
10008 /* See if this can be inverted. If it can't, possibly because
10009 it was a floating-point inequality comparison, don't do
10011 tem
= invert_truthvalue (arg0
);
10013 if (TREE_CODE (tem
) != TRUTH_NOT_EXPR
)
10014 return fold_build3 (code
, type
, tem
, op2
, op1
);
10017 /* Convert A ? 1 : 0 to simply A. */
10018 if (integer_onep (op1
)
10019 && integer_zerop (op2
)
10020 /* If we try to convert OP0 to our type, the
10021 call to fold will try to move the conversion inside
10022 a COND, which will recurse. In that case, the COND_EXPR
10023 is probably the best choice, so leave it alone. */
10024 && type
== TREE_TYPE (arg0
))
10025 return pedantic_non_lvalue (arg0
);
10027 /* Convert A ? 0 : 1 to !A. This prefers the use of NOT_EXPR
10028 over COND_EXPR in cases such as floating point comparisons. */
10029 if (integer_zerop (op1
)
10030 && integer_onep (op2
)
10031 && truth_value_p (TREE_CODE (arg0
)))
10032 return pedantic_non_lvalue (fold_convert (type
,
10033 invert_truthvalue (arg0
)));
10035 /* A < 0 ? <sign bit of A> : 0 is simply (A & <sign bit of A>). */
10036 if (TREE_CODE (arg0
) == LT_EXPR
10037 && integer_zerop (TREE_OPERAND (arg0
, 1))
10038 && integer_zerop (op2
)
10039 && (tem
= sign_bit_p (TREE_OPERAND (arg0
, 0), arg1
)))
10040 return fold_convert (type
, fold_build2 (BIT_AND_EXPR
,
10041 TREE_TYPE (tem
), tem
, arg1
));
10043 /* (A >> N) & 1 ? (1 << N) : 0 is simply A & (1 << N). A & 1 was
10044 already handled above. */
10045 if (TREE_CODE (arg0
) == BIT_AND_EXPR
10046 && integer_onep (TREE_OPERAND (arg0
, 1))
10047 && integer_zerop (op2
)
10048 && integer_pow2p (arg1
))
10050 tree tem
= TREE_OPERAND (arg0
, 0);
10052 if (TREE_CODE (tem
) == RSHIFT_EXPR
10053 && TREE_CODE (TREE_OPERAND (tem
, 1)) == INTEGER_CST
10054 && (unsigned HOST_WIDE_INT
) tree_log2 (arg1
) ==
10055 TREE_INT_CST_LOW (TREE_OPERAND (tem
, 1)))
10056 return fold_build2 (BIT_AND_EXPR
, type
,
10057 TREE_OPERAND (tem
, 0), arg1
);
10060 /* A & N ? N : 0 is simply A & N if N is a power of two. This
10061 is probably obsolete because the first operand should be a
10062 truth value (that's why we have the two cases above), but let's
10063 leave it in until we can confirm this for all front-ends. */
10064 if (integer_zerop (op2
)
10065 && TREE_CODE (arg0
) == NE_EXPR
10066 && integer_zerop (TREE_OPERAND (arg0
, 1))
10067 && integer_pow2p (arg1
)
10068 && TREE_CODE (TREE_OPERAND (arg0
, 0)) == BIT_AND_EXPR
10069 && operand_equal_p (TREE_OPERAND (TREE_OPERAND (arg0
, 0), 1),
10070 arg1
, OEP_ONLY_CONST
))
10071 return pedantic_non_lvalue (fold_convert (type
,
10072 TREE_OPERAND (arg0
, 0)));
10074 /* Convert A ? B : 0 into A && B if A and B are truth values. */
10075 if (integer_zerop (op2
)
10076 && truth_value_p (TREE_CODE (arg0
))
10077 && truth_value_p (TREE_CODE (arg1
)))
10078 return fold_build2 (TRUTH_ANDIF_EXPR
, type
, arg0
, arg1
);
10080 /* Convert A ? B : 1 into !A || B if A and B are truth values. */
10081 if (integer_onep (op2
)
10082 && truth_value_p (TREE_CODE (arg0
))
10083 && truth_value_p (TREE_CODE (arg1
)))
10085 /* Only perform transformation if ARG0 is easily inverted. */
10086 tem
= invert_truthvalue (arg0
);
10087 if (TREE_CODE (tem
) != TRUTH_NOT_EXPR
)
10088 return fold_build2 (TRUTH_ORIF_EXPR
, type
, tem
, arg1
);
10091 /* Convert A ? 0 : B into !A && B if A and B are truth values. */
10092 if (integer_zerop (arg1
)
10093 && truth_value_p (TREE_CODE (arg0
))
10094 && truth_value_p (TREE_CODE (op2
)))
10096 /* Only perform transformation if ARG0 is easily inverted. */
10097 tem
= invert_truthvalue (arg0
);
10098 if (TREE_CODE (tem
) != TRUTH_NOT_EXPR
)
10099 return fold_build2 (TRUTH_ANDIF_EXPR
, type
, tem
, op2
);
10102 /* Convert A ? 1 : B into A || B if A and B are truth values. */
10103 if (integer_onep (arg1
)
10104 && truth_value_p (TREE_CODE (arg0
))
10105 && truth_value_p (TREE_CODE (op2
)))
10106 return fold_build2 (TRUTH_ORIF_EXPR
, type
, arg0
, op2
);
10111 /* Check for a built-in function. */
10112 if (TREE_CODE (op0
) == ADDR_EXPR
10113 && TREE_CODE (TREE_OPERAND (op0
, 0)) == FUNCTION_DECL
10114 && DECL_BUILT_IN (TREE_OPERAND (op0
, 0)))
10116 tree fndecl
= TREE_OPERAND (op0
, 0);
10117 tree arglist
= op1
;
10118 tree tmp
= fold_builtin (fndecl
, arglist
, false);
10126 } /* switch (code) */
10129 /* Perform constant folding and related simplification of EXPR.
10130 The related simplifications include x*1 => x, x*0 => 0, etc.,
10131 and application of the associative law.
10132 NOP_EXPR conversions may be removed freely (as long as we
10133 are careful not to change the type of the overall expression).
10134 We cannot simplify through a CONVERT_EXPR, FIX_EXPR or FLOAT_EXPR,
10135 but we can constant-fold them if they have constant operands. */
10137 #ifdef ENABLE_FOLD_CHECKING
10138 # define fold(x) fold_1 (x)
10139 static tree
fold_1 (tree
);
10145 const tree t
= expr
;
10146 enum tree_code code
= TREE_CODE (t
);
10147 enum tree_code_class kind
= TREE_CODE_CLASS (code
);
10150 /* Return right away if a constant. */
10151 if (kind
== tcc_constant
)
10154 if (IS_EXPR_CODE_CLASS (kind
))
10156 tree type
= TREE_TYPE (t
);
10157 tree op0
, op1
, op2
;
10159 switch (TREE_CODE_LENGTH (code
))
10162 op0
= TREE_OPERAND (t
, 0);
10163 tem
= fold_unary (code
, type
, op0
);
10164 return tem
? tem
: expr
;
10166 op0
= TREE_OPERAND (t
, 0);
10167 op1
= TREE_OPERAND (t
, 1);
10168 tem
= fold_binary (code
, type
, op0
, op1
);
10169 return tem
? tem
: expr
;
10171 op0
= TREE_OPERAND (t
, 0);
10172 op1
= TREE_OPERAND (t
, 1);
10173 op2
= TREE_OPERAND (t
, 2);
10174 tem
= fold_ternary (code
, type
, op0
, op1
, op2
);
10175 return tem
? tem
: expr
;
10184 return fold (DECL_INITIAL (t
));
10188 } /* switch (code) */
10191 #ifdef ENABLE_FOLD_CHECKING
10194 static void fold_checksum_tree (tree
, struct md5_ctx
*, htab_t
);
10195 static void fold_check_failed (tree
, tree
);
10196 void print_fold_checksum (tree
);
10198 /* When --enable-checking=fold, compute a digest of expr before
10199 and after actual fold call to see if fold did not accidentally
10200 change original expr. */
10206 struct md5_ctx ctx
;
10207 unsigned char checksum_before
[16], checksum_after
[16];
10210 ht
= htab_create (32, htab_hash_pointer
, htab_eq_pointer
, NULL
);
10211 md5_init_ctx (&ctx
);
10212 fold_checksum_tree (expr
, &ctx
, ht
);
10213 md5_finish_ctx (&ctx
, checksum_before
);
10216 ret
= fold_1 (expr
);
10218 md5_init_ctx (&ctx
);
10219 fold_checksum_tree (expr
, &ctx
, ht
);
10220 md5_finish_ctx (&ctx
, checksum_after
);
10223 if (memcmp (checksum_before
, checksum_after
, 16))
10224 fold_check_failed (expr
, ret
);
10230 print_fold_checksum (tree expr
)
10232 struct md5_ctx ctx
;
10233 unsigned char checksum
[16], cnt
;
10236 ht
= htab_create (32, htab_hash_pointer
, htab_eq_pointer
, NULL
);
10237 md5_init_ctx (&ctx
);
10238 fold_checksum_tree (expr
, &ctx
, ht
);
10239 md5_finish_ctx (&ctx
, checksum
);
10241 for (cnt
= 0; cnt
< 16; ++cnt
)
10242 fprintf (stderr
, "%02x", checksum
[cnt
]);
10243 putc ('\n', stderr
);
10247 fold_check_failed (tree expr ATTRIBUTE_UNUSED
, tree ret ATTRIBUTE_UNUSED
)
10249 internal_error ("fold check: original tree changed by fold");
10253 fold_checksum_tree (tree expr
, struct md5_ctx
*ctx
, htab_t ht
)
10256 enum tree_code code
;
10257 char buf
[sizeof (struct tree_decl
)];
10260 gcc_assert ((sizeof (struct tree_exp
) + 5 * sizeof (tree
)
10261 <= sizeof (struct tree_decl
))
10262 && sizeof (struct tree_type
) <= sizeof (struct tree_decl
));
10265 slot
= htab_find_slot (ht
, expr
, INSERT
);
10269 code
= TREE_CODE (expr
);
10270 if (TREE_CODE_CLASS (code
) == tcc_declaration
10271 && DECL_ASSEMBLER_NAME_SET_P (expr
))
10273 /* Allow DECL_ASSEMBLER_NAME to be modified. */
10274 memcpy (buf
, expr
, tree_size (expr
));
10276 SET_DECL_ASSEMBLER_NAME (expr
, NULL
);
10278 else if (TREE_CODE_CLASS (code
) == tcc_type
10279 && (TYPE_POINTER_TO (expr
) || TYPE_REFERENCE_TO (expr
)
10280 || TYPE_CACHED_VALUES_P (expr
)))
10282 /* Allow these fields to be modified. */
10283 memcpy (buf
, expr
, tree_size (expr
));
10285 TYPE_POINTER_TO (expr
) = NULL
;
10286 TYPE_REFERENCE_TO (expr
) = NULL
;
10287 if (TYPE_CACHED_VALUES_P (expr
))
10289 TYPE_CACHED_VALUES_P (expr
) = 0;
10290 TYPE_CACHED_VALUES (expr
) = NULL
;
10293 md5_process_bytes (expr
, tree_size (expr
), ctx
);
10294 fold_checksum_tree (TREE_TYPE (expr
), ctx
, ht
);
10295 if (TREE_CODE_CLASS (code
) != tcc_type
10296 && TREE_CODE_CLASS (code
) != tcc_declaration
)
10297 fold_checksum_tree (TREE_CHAIN (expr
), ctx
, ht
);
10298 switch (TREE_CODE_CLASS (code
))
10304 md5_process_bytes (TREE_STRING_POINTER (expr
),
10305 TREE_STRING_LENGTH (expr
), ctx
);
10308 fold_checksum_tree (TREE_REALPART (expr
), ctx
, ht
);
10309 fold_checksum_tree (TREE_IMAGPART (expr
), ctx
, ht
);
10312 fold_checksum_tree (TREE_VECTOR_CST_ELTS (expr
), ctx
, ht
);
10318 case tcc_exceptional
:
10322 fold_checksum_tree (TREE_PURPOSE (expr
), ctx
, ht
);
10323 fold_checksum_tree (TREE_VALUE (expr
), ctx
, ht
);
10326 for (i
= 0; i
< TREE_VEC_LENGTH (expr
); ++i
)
10327 fold_checksum_tree (TREE_VEC_ELT (expr
, i
), ctx
, ht
);
10333 case tcc_expression
:
10334 case tcc_reference
:
10335 case tcc_comparison
:
10338 case tcc_statement
:
10339 len
= TREE_CODE_LENGTH (code
);
10340 for (i
= 0; i
< len
; ++i
)
10341 fold_checksum_tree (TREE_OPERAND (expr
, i
), ctx
, ht
);
10343 case tcc_declaration
:
10344 fold_checksum_tree (DECL_SIZE (expr
), ctx
, ht
);
10345 fold_checksum_tree (DECL_SIZE_UNIT (expr
), ctx
, ht
);
10346 fold_checksum_tree (DECL_NAME (expr
), ctx
, ht
);
10347 fold_checksum_tree (DECL_CONTEXT (expr
), ctx
, ht
);
10348 fold_checksum_tree (DECL_ARGUMENTS (expr
), ctx
, ht
);
10349 fold_checksum_tree (DECL_RESULT_FLD (expr
), ctx
, ht
);
10350 fold_checksum_tree (DECL_INITIAL (expr
), ctx
, ht
);
10351 fold_checksum_tree (DECL_ABSTRACT_ORIGIN (expr
), ctx
, ht
);
10352 fold_checksum_tree (DECL_SECTION_NAME (expr
), ctx
, ht
);
10353 fold_checksum_tree (DECL_ATTRIBUTES (expr
), ctx
, ht
);
10354 fold_checksum_tree (DECL_VINDEX (expr
), ctx
, ht
);
10357 if (TREE_CODE (expr
) == ENUMERAL_TYPE
)
10358 fold_checksum_tree (TYPE_VALUES (expr
), ctx
, ht
);
10359 fold_checksum_tree (TYPE_SIZE (expr
), ctx
, ht
);
10360 fold_checksum_tree (TYPE_SIZE_UNIT (expr
), ctx
, ht
);
10361 fold_checksum_tree (TYPE_ATTRIBUTES (expr
), ctx
, ht
);
10362 fold_checksum_tree (TYPE_NAME (expr
), ctx
, ht
);
10363 if (INTEGRAL_TYPE_P (expr
)
10364 || SCALAR_FLOAT_TYPE_P (expr
))
10366 fold_checksum_tree (TYPE_MIN_VALUE (expr
), ctx
, ht
);
10367 fold_checksum_tree (TYPE_MAX_VALUE (expr
), ctx
, ht
);
10369 fold_checksum_tree (TYPE_MAIN_VARIANT (expr
), ctx
, ht
);
10370 if (TREE_CODE (expr
) == RECORD_TYPE
10371 || TREE_CODE (expr
) == UNION_TYPE
10372 || TREE_CODE (expr
) == QUAL_UNION_TYPE
)
10373 fold_checksum_tree (TYPE_BINFO (expr
), ctx
, ht
);
10374 fold_checksum_tree (TYPE_CONTEXT (expr
), ctx
, ht
);
10383 /* Fold a unary tree expression with code CODE of type TYPE with an
10384 operand OP0. Return a folded expression if successful. Otherwise,
10385 return a tree expression with code CODE of type TYPE with an
10389 fold_build1 (enum tree_code code
, tree type
, tree op0
)
10391 tree tem
= fold_unary (code
, type
, op0
);
10395 return build1 (code
, type
, op0
);
10398 /* Fold a binary tree expression with code CODE of type TYPE with
10399 operands OP0 and OP1. Return a folded expression if successful.
10400 Otherwise, return a tree expression with code CODE of type TYPE
10401 with operands OP0 and OP1. */
10404 fold_build2 (enum tree_code code
, tree type
, tree op0
, tree op1
)
10406 tree tem
= fold_binary (code
, type
, op0
, op1
);
10410 return build2 (code
, type
, op0
, op1
);
10413 /* Fold a ternary tree expression with code CODE of type TYPE with
10414 operands OP0, OP1, and OP2. Return a folded expression if
10415 successful. Otherwise, return a tree expression with code CODE of
10416 type TYPE with operands OP0, OP1, and OP2. */
10419 fold_build3 (enum tree_code code
, tree type
, tree op0
, tree op1
, tree op2
)
10421 tree tem
= fold_ternary (code
, type
, op0
, op1
, op2
);
10425 return build3 (code
, type
, op0
, op1
, op2
);
10428 /* Perform constant folding and related simplification of initializer
10429 expression EXPR. This behaves identically to "fold" but ignores
10430 potential run-time traps and exceptions that fold must preserve. */
10433 fold_initializer (tree expr
)
10435 int saved_signaling_nans
= flag_signaling_nans
;
10436 int saved_trapping_math
= flag_trapping_math
;
10437 int saved_rounding_math
= flag_rounding_math
;
10438 int saved_trapv
= flag_trapv
;
10441 flag_signaling_nans
= 0;
10442 flag_trapping_math
= 0;
10443 flag_rounding_math
= 0;
10446 result
= fold (expr
);
10448 flag_signaling_nans
= saved_signaling_nans
;
10449 flag_trapping_math
= saved_trapping_math
;
10450 flag_rounding_math
= saved_rounding_math
;
10451 flag_trapv
= saved_trapv
;
10456 /* Determine if first argument is a multiple of second argument. Return 0 if
10457 it is not, or we cannot easily determined it to be.
10459 An example of the sort of thing we care about (at this point; this routine
10460 could surely be made more general, and expanded to do what the *_DIV_EXPR's
10461 fold cases do now) is discovering that
10463 SAVE_EXPR (I) * SAVE_EXPR (J * 8)
10469 when we know that the two SAVE_EXPR (J * 8) nodes are the same node.
10471 This code also handles discovering that
10473 SAVE_EXPR (I) * SAVE_EXPR (J * 8)
10475 is a multiple of 8 so we don't have to worry about dealing with a
10476 possible remainder.
10478 Note that we *look* inside a SAVE_EXPR only to determine how it was
10479 calculated; it is not safe for fold to do much of anything else with the
10480 internals of a SAVE_EXPR, since it cannot know when it will be evaluated
10481 at run time. For example, the latter example above *cannot* be implemented
10482 as SAVE_EXPR (I) * J or any variant thereof, since the value of J at
10483 evaluation time of the original SAVE_EXPR is not necessarily the same at
10484 the time the new expression is evaluated. The only optimization of this
10485 sort that would be valid is changing
10487 SAVE_EXPR (I) * SAVE_EXPR (SAVE_EXPR (J) * 8)
10491 SAVE_EXPR (I) * SAVE_EXPR (J)
10493 (where the same SAVE_EXPR (J) is used in the original and the
10494 transformed version). */
10497 multiple_of_p (tree type
, tree top
, tree bottom
)
10499 if (operand_equal_p (top
, bottom
, 0))
10502 if (TREE_CODE (type
) != INTEGER_TYPE
)
10505 switch (TREE_CODE (top
))
10508 /* Bitwise and provides a power of two multiple. If the mask is
10509 a multiple of BOTTOM then TOP is a multiple of BOTTOM. */
10510 if (!integer_pow2p (bottom
))
10515 return (multiple_of_p (type
, TREE_OPERAND (top
, 0), bottom
)
10516 || multiple_of_p (type
, TREE_OPERAND (top
, 1), bottom
));
10520 return (multiple_of_p (type
, TREE_OPERAND (top
, 0), bottom
)
10521 && multiple_of_p (type
, TREE_OPERAND (top
, 1), bottom
));
10524 if (TREE_CODE (TREE_OPERAND (top
, 1)) == INTEGER_CST
)
10528 op1
= TREE_OPERAND (top
, 1);
10529 /* const_binop may not detect overflow correctly,
10530 so check for it explicitly here. */
10531 if (TYPE_PRECISION (TREE_TYPE (size_one_node
))
10532 > TREE_INT_CST_LOW (op1
)
10533 && TREE_INT_CST_HIGH (op1
) == 0
10534 && 0 != (t1
= fold_convert (type
,
10535 const_binop (LSHIFT_EXPR
,
10538 && ! TREE_OVERFLOW (t1
))
10539 return multiple_of_p (type
, t1
, bottom
);
10544 /* Can't handle conversions from non-integral or wider integral type. */
10545 if ((TREE_CODE (TREE_TYPE (TREE_OPERAND (top
, 0))) != INTEGER_TYPE
)
10546 || (TYPE_PRECISION (type
)
10547 < TYPE_PRECISION (TREE_TYPE (TREE_OPERAND (top
, 0)))))
10550 /* .. fall through ... */
10553 return multiple_of_p (type
, TREE_OPERAND (top
, 0), bottom
);
10556 if (TREE_CODE (bottom
) != INTEGER_CST
10557 || (TYPE_UNSIGNED (type
)
10558 && (tree_int_cst_sgn (top
) < 0
10559 || tree_int_cst_sgn (bottom
) < 0)))
10561 return integer_zerop (const_binop (TRUNC_MOD_EXPR
,
10569 /* Return true if `t' is known to be non-negative. */
10572 tree_expr_nonnegative_p (tree t
)
10574 switch (TREE_CODE (t
))
10580 return tree_int_cst_sgn (t
) >= 0;
10583 return ! REAL_VALUE_NEGATIVE (TREE_REAL_CST (t
));
10586 if (FLOAT_TYPE_P (TREE_TYPE (t
)))
10587 return tree_expr_nonnegative_p (TREE_OPERAND (t
, 0))
10588 && tree_expr_nonnegative_p (TREE_OPERAND (t
, 1));
10590 /* zero_extend(x) + zero_extend(y) is non-negative if x and y are
10591 both unsigned and at least 2 bits shorter than the result. */
10592 if (TREE_CODE (TREE_TYPE (t
)) == INTEGER_TYPE
10593 && TREE_CODE (TREE_OPERAND (t
, 0)) == NOP_EXPR
10594 && TREE_CODE (TREE_OPERAND (t
, 1)) == NOP_EXPR
)
10596 tree inner1
= TREE_TYPE (TREE_OPERAND (TREE_OPERAND (t
, 0), 0));
10597 tree inner2
= TREE_TYPE (TREE_OPERAND (TREE_OPERAND (t
, 1), 0));
10598 if (TREE_CODE (inner1
) == INTEGER_TYPE
&& TYPE_UNSIGNED (inner1
)
10599 && TREE_CODE (inner2
) == INTEGER_TYPE
&& TYPE_UNSIGNED (inner2
))
10601 unsigned int prec
= MAX (TYPE_PRECISION (inner1
),
10602 TYPE_PRECISION (inner2
)) + 1;
10603 return prec
< TYPE_PRECISION (TREE_TYPE (t
));
10609 if (FLOAT_TYPE_P (TREE_TYPE (t
)))
10611 /* x * x for floating point x is always non-negative. */
10612 if (operand_equal_p (TREE_OPERAND (t
, 0), TREE_OPERAND (t
, 1), 0))
10614 return tree_expr_nonnegative_p (TREE_OPERAND (t
, 0))
10615 && tree_expr_nonnegative_p (TREE_OPERAND (t
, 1));
10618 /* zero_extend(x) * zero_extend(y) is non-negative if x and y are
10619 both unsigned and their total bits is shorter than the result. */
10620 if (TREE_CODE (TREE_TYPE (t
)) == INTEGER_TYPE
10621 && TREE_CODE (TREE_OPERAND (t
, 0)) == NOP_EXPR
10622 && TREE_CODE (TREE_OPERAND (t
, 1)) == NOP_EXPR
)
10624 tree inner1
= TREE_TYPE (TREE_OPERAND (TREE_OPERAND (t
, 0), 0));
10625 tree inner2
= TREE_TYPE (TREE_OPERAND (TREE_OPERAND (t
, 1), 0));
10626 if (TREE_CODE (inner1
) == INTEGER_TYPE
&& TYPE_UNSIGNED (inner1
)
10627 && TREE_CODE (inner2
) == INTEGER_TYPE
&& TYPE_UNSIGNED (inner2
))
10628 return TYPE_PRECISION (inner1
) + TYPE_PRECISION (inner2
)
10629 < TYPE_PRECISION (TREE_TYPE (t
));
10633 case TRUNC_DIV_EXPR
:
10634 case CEIL_DIV_EXPR
:
10635 case FLOOR_DIV_EXPR
:
10636 case ROUND_DIV_EXPR
:
10637 return tree_expr_nonnegative_p (TREE_OPERAND (t
, 0))
10638 && tree_expr_nonnegative_p (TREE_OPERAND (t
, 1));
10640 case TRUNC_MOD_EXPR
:
10641 case CEIL_MOD_EXPR
:
10642 case FLOOR_MOD_EXPR
:
10643 case ROUND_MOD_EXPR
:
10644 return tree_expr_nonnegative_p (TREE_OPERAND (t
, 0));
10647 return tree_expr_nonnegative_p (TREE_OPERAND (t
, 0))
10648 && tree_expr_nonnegative_p (TREE_OPERAND (t
, 1));
10651 return tree_expr_nonnegative_p (TREE_OPERAND (t
, 1))
10652 || tree_expr_nonnegative_p (TREE_OPERAND (t
, 0));
10655 return tree_expr_nonnegative_p (TREE_OPERAND (t
, 0))
10656 && tree_expr_nonnegative_p (TREE_OPERAND (t
, 1));
10660 tree inner_type
= TREE_TYPE (TREE_OPERAND (t
, 0));
10661 tree outer_type
= TREE_TYPE (t
);
10663 if (TREE_CODE (outer_type
) == REAL_TYPE
)
10665 if (TREE_CODE (inner_type
) == REAL_TYPE
)
10666 return tree_expr_nonnegative_p (TREE_OPERAND (t
, 0));
10667 if (TREE_CODE (inner_type
) == INTEGER_TYPE
)
10669 if (TYPE_UNSIGNED (inner_type
))
10671 return tree_expr_nonnegative_p (TREE_OPERAND (t
, 0));
10674 else if (TREE_CODE (outer_type
) == INTEGER_TYPE
)
10676 if (TREE_CODE (inner_type
) == REAL_TYPE
)
10677 return tree_expr_nonnegative_p (TREE_OPERAND (t
,0));
10678 if (TREE_CODE (inner_type
) == INTEGER_TYPE
)
10679 return TYPE_PRECISION (inner_type
) < TYPE_PRECISION (outer_type
)
10680 && TYPE_UNSIGNED (inner_type
);
10686 return tree_expr_nonnegative_p (TREE_OPERAND (t
, 1))
10687 && tree_expr_nonnegative_p (TREE_OPERAND (t
, 2));
10688 case COMPOUND_EXPR
:
10689 return tree_expr_nonnegative_p (TREE_OPERAND (t
, 1));
10691 return tree_expr_nonnegative_p (TREE_OPERAND (t
, 0))
10692 && tree_expr_nonnegative_p (TREE_OPERAND (t
, 1));
10694 return tree_expr_nonnegative_p (TREE_OPERAND (t
, 0))
10695 || tree_expr_nonnegative_p (TREE_OPERAND (t
, 1));
10697 return tree_expr_nonnegative_p (TREE_OPERAND (t
, 1));
10699 return tree_expr_nonnegative_p (expr_last (TREE_OPERAND (t
, 1)));
10701 return tree_expr_nonnegative_p (TREE_OPERAND (t
, 0));
10702 case NON_LVALUE_EXPR
:
10703 return tree_expr_nonnegative_p (TREE_OPERAND (t
, 0));
10705 return tree_expr_nonnegative_p (TREE_OPERAND (t
, 0));
10709 tree temp
= TARGET_EXPR_SLOT (t
);
10710 t
= TARGET_EXPR_INITIAL (t
);
10712 /* If the initializer is non-void, then it's a normal expression
10713 that will be assigned to the slot. */
10714 if (!VOID_TYPE_P (t
))
10715 return tree_expr_nonnegative_p (t
);
10717 /* Otherwise, the initializer sets the slot in some way. One common
10718 way is an assignment statement at the end of the initializer. */
10721 if (TREE_CODE (t
) == BIND_EXPR
)
10722 t
= expr_last (BIND_EXPR_BODY (t
));
10723 else if (TREE_CODE (t
) == TRY_FINALLY_EXPR
10724 || TREE_CODE (t
) == TRY_CATCH_EXPR
)
10725 t
= expr_last (TREE_OPERAND (t
, 0));
10726 else if (TREE_CODE (t
) == STATEMENT_LIST
)
10731 if (TREE_CODE (t
) == MODIFY_EXPR
10732 && TREE_OPERAND (t
, 0) == temp
)
10733 return tree_expr_nonnegative_p (TREE_OPERAND (t
, 1));
10740 tree fndecl
= get_callee_fndecl (t
);
10741 tree arglist
= TREE_OPERAND (t
, 1);
10742 if (fndecl
&& DECL_BUILT_IN_CLASS (fndecl
) == BUILT_IN_NORMAL
)
10743 switch (DECL_FUNCTION_CODE (fndecl
))
10745 #define CASE_BUILTIN_F(BUILT_IN_FN) \
10746 case BUILT_IN_FN: case BUILT_IN_FN##F: case BUILT_IN_FN##L:
10747 #define CASE_BUILTIN_I(BUILT_IN_FN) \
10748 case BUILT_IN_FN: case BUILT_IN_FN##L: case BUILT_IN_FN##LL:
10750 CASE_BUILTIN_F (BUILT_IN_ACOS
)
10751 CASE_BUILTIN_F (BUILT_IN_ACOSH
)
10752 CASE_BUILTIN_F (BUILT_IN_CABS
)
10753 CASE_BUILTIN_F (BUILT_IN_COSH
)
10754 CASE_BUILTIN_F (BUILT_IN_ERFC
)
10755 CASE_BUILTIN_F (BUILT_IN_EXP
)
10756 CASE_BUILTIN_F (BUILT_IN_EXP10
)
10757 CASE_BUILTIN_F (BUILT_IN_EXP2
)
10758 CASE_BUILTIN_F (BUILT_IN_FABS
)
10759 CASE_BUILTIN_F (BUILT_IN_FDIM
)
10760 CASE_BUILTIN_F (BUILT_IN_FREXP
)
10761 CASE_BUILTIN_F (BUILT_IN_HYPOT
)
10762 CASE_BUILTIN_F (BUILT_IN_POW10
)
10763 CASE_BUILTIN_I (BUILT_IN_FFS
)
10764 CASE_BUILTIN_I (BUILT_IN_PARITY
)
10765 CASE_BUILTIN_I (BUILT_IN_POPCOUNT
)
10769 CASE_BUILTIN_F (BUILT_IN_SQRT
)
10770 /* sqrt(-0.0) is -0.0. */
10771 if (!HONOR_SIGNED_ZEROS (TYPE_MODE (TREE_TYPE (t
))))
10773 return tree_expr_nonnegative_p (TREE_VALUE (arglist
));
10775 CASE_BUILTIN_F (BUILT_IN_ASINH
)
10776 CASE_BUILTIN_F (BUILT_IN_ATAN
)
10777 CASE_BUILTIN_F (BUILT_IN_ATANH
)
10778 CASE_BUILTIN_F (BUILT_IN_CBRT
)
10779 CASE_BUILTIN_F (BUILT_IN_CEIL
)
10780 CASE_BUILTIN_F (BUILT_IN_ERF
)
10781 CASE_BUILTIN_F (BUILT_IN_EXPM1
)
10782 CASE_BUILTIN_F (BUILT_IN_FLOOR
)
10783 CASE_BUILTIN_F (BUILT_IN_FMOD
)
10784 CASE_BUILTIN_F (BUILT_IN_LCEIL
)
10785 CASE_BUILTIN_F (BUILT_IN_LDEXP
)
10786 CASE_BUILTIN_F (BUILT_IN_LFLOOR
)
10787 CASE_BUILTIN_F (BUILT_IN_LLCEIL
)
10788 CASE_BUILTIN_F (BUILT_IN_LLFLOOR
)
10789 CASE_BUILTIN_F (BUILT_IN_LLRINT
)
10790 CASE_BUILTIN_F (BUILT_IN_LLROUND
)
10791 CASE_BUILTIN_F (BUILT_IN_LRINT
)
10792 CASE_BUILTIN_F (BUILT_IN_LROUND
)
10793 CASE_BUILTIN_F (BUILT_IN_MODF
)
10794 CASE_BUILTIN_F (BUILT_IN_NEARBYINT
)
10795 CASE_BUILTIN_F (BUILT_IN_POW
)
10796 CASE_BUILTIN_F (BUILT_IN_RINT
)
10797 CASE_BUILTIN_F (BUILT_IN_ROUND
)
10798 CASE_BUILTIN_F (BUILT_IN_SIGNBIT
)
10799 CASE_BUILTIN_F (BUILT_IN_SINH
)
10800 CASE_BUILTIN_F (BUILT_IN_TANH
)
10801 CASE_BUILTIN_F (BUILT_IN_TRUNC
)
10802 /* True if the 1st argument is nonnegative. */
10803 return tree_expr_nonnegative_p (TREE_VALUE (arglist
));
10805 CASE_BUILTIN_F (BUILT_IN_FMAX
)
10806 /* True if the 1st OR 2nd arguments are nonnegative. */
10807 return tree_expr_nonnegative_p (TREE_VALUE (arglist
))
10808 || tree_expr_nonnegative_p (TREE_VALUE (TREE_CHAIN (arglist
)));
10810 CASE_BUILTIN_F (BUILT_IN_FMIN
)
10811 /* True if the 1st AND 2nd arguments are nonnegative. */
10812 return tree_expr_nonnegative_p (TREE_VALUE (arglist
))
10813 && tree_expr_nonnegative_p (TREE_VALUE (TREE_CHAIN (arglist
)));
10815 CASE_BUILTIN_F (BUILT_IN_COPYSIGN
)
10816 /* True if the 2nd argument is nonnegative. */
10817 return tree_expr_nonnegative_p (TREE_VALUE (TREE_CHAIN (arglist
)));
10821 #undef CASE_BUILTIN_F
10822 #undef CASE_BUILTIN_I
10826 /* ... fall through ... */
10829 if (truth_value_p (TREE_CODE (t
)))
10830 /* Truth values evaluate to 0 or 1, which is nonnegative. */
10834 /* We don't know sign of `t', so be conservative and return false. */
10838 /* Return true when T is an address and is known to be nonzero.
10839 For floating point we further ensure that T is not denormal.
10840 Similar logic is present in nonzero_address in rtlanal.h. */
10843 tree_expr_nonzero_p (tree t
)
10845 tree type
= TREE_TYPE (t
);
10847 /* Doing something useful for floating point would need more work. */
10848 if (!INTEGRAL_TYPE_P (type
) && !POINTER_TYPE_P (type
))
10851 switch (TREE_CODE (t
))
10854 if (!TYPE_UNSIGNED (type
) && !flag_wrapv
)
10855 return tree_expr_nonzero_p (TREE_OPERAND (t
, 0));
10858 /* We used to test for !integer_zerop here. This does not work correctly
10859 if TREE_CONSTANT_OVERFLOW (t). */
10860 return (TREE_INT_CST_LOW (t
) != 0
10861 || TREE_INT_CST_HIGH (t
) != 0);
10864 if (!TYPE_UNSIGNED (type
) && !flag_wrapv
)
10866 /* With the presence of negative values it is hard
10867 to say something. */
10868 if (!tree_expr_nonnegative_p (TREE_OPERAND (t
, 0))
10869 || !tree_expr_nonnegative_p (TREE_OPERAND (t
, 1)))
10871 /* One of operands must be positive and the other non-negative. */
10872 return (tree_expr_nonzero_p (TREE_OPERAND (t
, 0))
10873 || tree_expr_nonzero_p (TREE_OPERAND (t
, 1)));
10878 if (!TYPE_UNSIGNED (type
) && !flag_wrapv
)
10880 return (tree_expr_nonzero_p (TREE_OPERAND (t
, 0))
10881 && tree_expr_nonzero_p (TREE_OPERAND (t
, 1)));
10887 tree inner_type
= TREE_TYPE (TREE_OPERAND (t
, 0));
10888 tree outer_type
= TREE_TYPE (t
);
10890 return (TYPE_PRECISION (inner_type
) >= TYPE_PRECISION (outer_type
)
10891 && tree_expr_nonzero_p (TREE_OPERAND (t
, 0)));
10897 tree base
= get_base_address (TREE_OPERAND (t
, 0));
10902 /* Weak declarations may link to NULL. */
10904 return !DECL_WEAK (base
);
10906 /* Constants are never weak. */
10907 if (CONSTANT_CLASS_P (base
))
10914 return (tree_expr_nonzero_p (TREE_OPERAND (t
, 1))
10915 && tree_expr_nonzero_p (TREE_OPERAND (t
, 2)));
10918 return (tree_expr_nonzero_p (TREE_OPERAND (t
, 0))
10919 && tree_expr_nonzero_p (TREE_OPERAND (t
, 1)));
10922 if (tree_expr_nonzero_p (TREE_OPERAND (t
, 0)))
10924 /* When both operands are nonzero, then MAX must be too. */
10925 if (tree_expr_nonzero_p (TREE_OPERAND (t
, 1)))
10928 /* MAX where operand 0 is positive is positive. */
10929 return tree_expr_nonnegative_p (TREE_OPERAND (t
, 0));
10931 /* MAX where operand 1 is positive is positive. */
10932 else if (tree_expr_nonzero_p (TREE_OPERAND (t
, 1))
10933 && tree_expr_nonnegative_p (TREE_OPERAND (t
, 1)))
10937 case COMPOUND_EXPR
:
10940 return tree_expr_nonzero_p (TREE_OPERAND (t
, 1));
10943 case NON_LVALUE_EXPR
:
10944 return tree_expr_nonzero_p (TREE_OPERAND (t
, 0));
10947 return tree_expr_nonzero_p (TREE_OPERAND (t
, 1))
10948 || tree_expr_nonzero_p (TREE_OPERAND (t
, 0));
10956 /* Given the components of a binary expression CODE, TYPE, OP0 and OP1,
10957 attempt to fold the expression to a constant without modifying TYPE,
10960 If the expression could be simplified to a constant, then return
10961 the constant. If the expression would not be simplified to a
10962 constant, then return NULL_TREE. */
10965 fold_binary_to_constant (enum tree_code code
, tree type
, tree op0
, tree op1
)
10967 tree tem
= fold_binary (code
, type
, op0
, op1
);
10968 return (tem
&& TREE_CONSTANT (tem
)) ? tem
: NULL_TREE
;
10971 /* Given the components of a unary expression CODE, TYPE and OP0,
10972 attempt to fold the expression to a constant without modifying
10975 If the expression could be simplified to a constant, then return
10976 the constant. If the expression would not be simplified to a
10977 constant, then return NULL_TREE. */
10980 fold_unary_to_constant (enum tree_code code
, tree type
, tree op0
)
10982 tree tem
= fold_unary (code
, type
, op0
);
10983 return (tem
&& TREE_CONSTANT (tem
)) ? tem
: NULL_TREE
;
10986 /* If EXP represents referencing an element in a constant string
10987 (either via pointer arithmetic or array indexing), return the
10988 tree representing the value accessed, otherwise return NULL. */
10991 fold_read_from_constant_string (tree exp
)
10993 if (TREE_CODE (exp
) == INDIRECT_REF
|| TREE_CODE (exp
) == ARRAY_REF
)
10995 tree exp1
= TREE_OPERAND (exp
, 0);
10999 if (TREE_CODE (exp
) == INDIRECT_REF
)
11000 string
= string_constant (exp1
, &index
);
11003 tree low_bound
= array_ref_low_bound (exp
);
11004 index
= fold_convert (sizetype
, TREE_OPERAND (exp
, 1));
11006 /* Optimize the special-case of a zero lower bound.
11008 We convert the low_bound to sizetype to avoid some problems
11009 with constant folding. (E.g. suppose the lower bound is 1,
11010 and its mode is QI. Without the conversion,l (ARRAY
11011 +(INDEX-(unsigned char)1)) becomes ((ARRAY+(-(unsigned char)1))
11012 +INDEX), which becomes (ARRAY+255+INDEX). Opps!) */
11013 if (! integer_zerop (low_bound
))
11014 index
= size_diffop (index
, fold_convert (sizetype
, low_bound
));
11020 && TREE_TYPE (exp
) == TREE_TYPE (TREE_TYPE (string
))
11021 && TREE_CODE (string
) == STRING_CST
11022 && TREE_CODE (index
) == INTEGER_CST
11023 && compare_tree_int (index
, TREE_STRING_LENGTH (string
)) < 0
11024 && (GET_MODE_CLASS (TYPE_MODE (TREE_TYPE (TREE_TYPE (string
))))
11026 && (GET_MODE_SIZE (TYPE_MODE (TREE_TYPE (TREE_TYPE (string
)))) == 1))
11027 return fold_convert (TREE_TYPE (exp
),
11028 build_int_cst (NULL_TREE
,
11029 (TREE_STRING_POINTER (string
)
11030 [TREE_INT_CST_LOW (index
)])));
11035 /* Return the tree for neg (ARG0) when ARG0 is known to be either
11036 an integer constant or real constant.
11038 TYPE is the type of the result. */
11041 fold_negate_const (tree arg0
, tree type
)
11043 tree t
= NULL_TREE
;
11045 switch (TREE_CODE (arg0
))
11049 unsigned HOST_WIDE_INT low
;
11050 HOST_WIDE_INT high
;
11051 int overflow
= neg_double (TREE_INT_CST_LOW (arg0
),
11052 TREE_INT_CST_HIGH (arg0
),
11054 t
= build_int_cst_wide (type
, low
, high
);
11055 t
= force_fit_type (t
, 1,
11056 (overflow
| TREE_OVERFLOW (arg0
))
11057 && !TYPE_UNSIGNED (type
),
11058 TREE_CONSTANT_OVERFLOW (arg0
));
11063 t
= build_real (type
, REAL_VALUE_NEGATE (TREE_REAL_CST (arg0
)));
11067 gcc_unreachable ();
11073 /* Return the tree for abs (ARG0) when ARG0 is known to be either
11074 an integer constant or real constant.
11076 TYPE is the type of the result. */
11079 fold_abs_const (tree arg0
, tree type
)
11081 tree t
= NULL_TREE
;
11083 switch (TREE_CODE (arg0
))
11086 /* If the value is unsigned, then the absolute value is
11087 the same as the ordinary value. */
11088 if (TYPE_UNSIGNED (type
))
11090 /* Similarly, if the value is non-negative. */
11091 else if (INT_CST_LT (integer_minus_one_node
, arg0
))
11093 /* If the value is negative, then the absolute value is
11097 unsigned HOST_WIDE_INT low
;
11098 HOST_WIDE_INT high
;
11099 int overflow
= neg_double (TREE_INT_CST_LOW (arg0
),
11100 TREE_INT_CST_HIGH (arg0
),
11102 t
= build_int_cst_wide (type
, low
, high
);
11103 t
= force_fit_type (t
, -1, overflow
| TREE_OVERFLOW (arg0
),
11104 TREE_CONSTANT_OVERFLOW (arg0
));
11109 if (REAL_VALUE_NEGATIVE (TREE_REAL_CST (arg0
)))
11110 t
= build_real (type
, REAL_VALUE_NEGATE (TREE_REAL_CST (arg0
)));
11116 gcc_unreachable ();
11122 /* Return the tree for not (ARG0) when ARG0 is known to be an integer
11123 constant. TYPE is the type of the result. */
11126 fold_not_const (tree arg0
, tree type
)
11128 tree t
= NULL_TREE
;
11130 gcc_assert (TREE_CODE (arg0
) == INTEGER_CST
);
11132 t
= build_int_cst_wide (type
,
11133 ~ TREE_INT_CST_LOW (arg0
),
11134 ~ TREE_INT_CST_HIGH (arg0
));
11135 t
= force_fit_type (t
, 0, TREE_OVERFLOW (arg0
),
11136 TREE_CONSTANT_OVERFLOW (arg0
));
11141 /* Given CODE, a relational operator, the target type, TYPE and two
11142 constant operands OP0 and OP1, return the result of the
11143 relational operation. If the result is not a compile time
11144 constant, then return NULL_TREE. */
11147 fold_relational_const (enum tree_code code
, tree type
, tree op0
, tree op1
)
11149 int result
, invert
;
11151 /* From here on, the only cases we handle are when the result is
11152 known to be a constant. */
11154 if (TREE_CODE (op0
) == REAL_CST
&& TREE_CODE (op1
) == REAL_CST
)
11156 const REAL_VALUE_TYPE
*c0
= TREE_REAL_CST_PTR (op0
);
11157 const REAL_VALUE_TYPE
*c1
= TREE_REAL_CST_PTR (op1
);
11159 /* Handle the cases where either operand is a NaN. */
11160 if (real_isnan (c0
) || real_isnan (c1
))
11170 case UNORDERED_EXPR
:
11184 if (flag_trapping_math
)
11190 gcc_unreachable ();
11193 return constant_boolean_node (result
, type
);
11196 return constant_boolean_node (real_compare (code
, c0
, c1
), type
);
11199 /* From here on we only handle LT, LE, GT, GE, EQ and NE.
11201 To compute GT, swap the arguments and do LT.
11202 To compute GE, do LT and invert the result.
11203 To compute LE, swap the arguments, do LT and invert the result.
11204 To compute NE, do EQ and invert the result.
11206 Therefore, the code below must handle only EQ and LT. */
11208 if (code
== LE_EXPR
|| code
== GT_EXPR
)
11213 code
= swap_tree_comparison (code
);
11216 /* Note that it is safe to invert for real values here because we
11217 have already handled the one case that it matters. */
11220 if (code
== NE_EXPR
|| code
== GE_EXPR
)
11223 code
= invert_tree_comparison (code
, false);
11226 /* Compute a result for LT or EQ if args permit;
11227 Otherwise return T. */
11228 if (TREE_CODE (op0
) == INTEGER_CST
&& TREE_CODE (op1
) == INTEGER_CST
)
11230 if (code
== EQ_EXPR
)
11231 result
= tree_int_cst_equal (op0
, op1
);
11232 else if (TYPE_UNSIGNED (TREE_TYPE (op0
)))
11233 result
= INT_CST_LT_UNSIGNED (op0
, op1
);
11235 result
= INT_CST_LT (op0
, op1
);
11242 return constant_boolean_node (result
, type
);
11245 /* Build an expression for the a clean point containing EXPR with type TYPE.
11246 Don't build a cleanup point expression for EXPR which don't have side
11250 fold_build_cleanup_point_expr (tree type
, tree expr
)
11252 /* If the expression does not have side effects then we don't have to wrap
11253 it with a cleanup point expression. */
11254 if (!TREE_SIDE_EFFECTS (expr
))
11257 /* If the expression is a return, check to see if the expression inside the
11258 return has no side effects or the right hand side of the modify expression
11259 inside the return. If either don't have side effects set we don't need to
11260 wrap the expression in a cleanup point expression. Note we don't check the
11261 left hand side of the modify because it should always be a return decl. */
11262 if (TREE_CODE (expr
) == RETURN_EXPR
)
11264 tree op
= TREE_OPERAND (expr
, 0);
11265 if (!op
|| !TREE_SIDE_EFFECTS (op
))
11267 op
= TREE_OPERAND (op
, 1);
11268 if (!TREE_SIDE_EFFECTS (op
))
11272 return build1 (CLEANUP_POINT_EXPR
, type
, expr
);
11275 /* Build an expression for the address of T. Folds away INDIRECT_REF to
11276 avoid confusing the gimplify process. */
11279 build_fold_addr_expr_with_type (tree t
, tree ptrtype
)
11281 /* The size of the object is not relevant when talking about its address. */
11282 if (TREE_CODE (t
) == WITH_SIZE_EXPR
)
11283 t
= TREE_OPERAND (t
, 0);
11285 /* Note: doesn't apply to ALIGN_INDIRECT_REF */
11286 if (TREE_CODE (t
) == INDIRECT_REF
11287 || TREE_CODE (t
) == MISALIGNED_INDIRECT_REF
)
11289 t
= TREE_OPERAND (t
, 0);
11290 if (TREE_TYPE (t
) != ptrtype
)
11291 t
= build1 (NOP_EXPR
, ptrtype
, t
);
11297 while (handled_component_p (base
))
11298 base
= TREE_OPERAND (base
, 0);
11300 TREE_ADDRESSABLE (base
) = 1;
11302 t
= build1 (ADDR_EXPR
, ptrtype
, t
);
11309 build_fold_addr_expr (tree t
)
11311 return build_fold_addr_expr_with_type (t
, build_pointer_type (TREE_TYPE (t
)));
11314 /* Given a pointer value T, return a simplified version of an indirection
11315 through T, or NULL_TREE if no simplification is possible. */
11318 fold_indirect_ref_1 (tree t
)
11320 tree type
= TREE_TYPE (TREE_TYPE (t
));
11325 subtype
= TREE_TYPE (sub
);
11326 if (!POINTER_TYPE_P (subtype
))
11329 if (TREE_CODE (sub
) == ADDR_EXPR
)
11331 tree op
= TREE_OPERAND (sub
, 0);
11332 tree optype
= TREE_TYPE (op
);
11334 if (lang_hooks
.types_compatible_p (type
, optype
))
11336 /* *(foo *)&fooarray => fooarray[0] */
11337 else if (TREE_CODE (optype
) == ARRAY_TYPE
11338 && lang_hooks
.types_compatible_p (type
, TREE_TYPE (optype
)))
11340 tree type_domain
= TYPE_DOMAIN (optype
);
11341 tree min_val
= size_zero_node
;
11342 if (type_domain
&& TYPE_MIN_VALUE (type_domain
))
11343 min_val
= TYPE_MIN_VALUE (type_domain
);
11344 return build4 (ARRAY_REF
, type
, op
, min_val
, NULL_TREE
, NULL_TREE
);
11348 /* *(foo *)fooarrptr => (*fooarrptr)[0] */
11349 if (TREE_CODE (TREE_TYPE (subtype
)) == ARRAY_TYPE
11350 && lang_hooks
.types_compatible_p (type
, TREE_TYPE (TREE_TYPE (subtype
))))
11353 tree min_val
= size_zero_node
;
11354 sub
= build_fold_indirect_ref (sub
);
11355 type_domain
= TYPE_DOMAIN (TREE_TYPE (sub
));
11356 if (type_domain
&& TYPE_MIN_VALUE (type_domain
))
11357 min_val
= TYPE_MIN_VALUE (type_domain
);
11358 return build4 (ARRAY_REF
, type
, sub
, min_val
, NULL_TREE
, NULL_TREE
);
11364 /* Builds an expression for an indirection through T, simplifying some
11368 build_fold_indirect_ref (tree t
)
11370 tree sub
= fold_indirect_ref_1 (t
);
11375 return build1 (INDIRECT_REF
, TREE_TYPE (TREE_TYPE (t
)), t
);
11378 /* Given an INDIRECT_REF T, return either T or a simplified version. */
11381 fold_indirect_ref (tree t
)
11383 tree sub
= fold_indirect_ref_1 (TREE_OPERAND (t
, 0));
11391 /* Strip non-trapping, non-side-effecting tree nodes from an expression
11392 whose result is ignored. The type of the returned tree need not be
11393 the same as the original expression. */
11396 fold_ignored_result (tree t
)
11398 if (!TREE_SIDE_EFFECTS (t
))
11399 return integer_zero_node
;
11402 switch (TREE_CODE_CLASS (TREE_CODE (t
)))
11405 t
= TREE_OPERAND (t
, 0);
11409 case tcc_comparison
:
11410 if (!TREE_SIDE_EFFECTS (TREE_OPERAND (t
, 1)))
11411 t
= TREE_OPERAND (t
, 0);
11412 else if (!TREE_SIDE_EFFECTS (TREE_OPERAND (t
, 0)))
11413 t
= TREE_OPERAND (t
, 1);
11418 case tcc_expression
:
11419 switch (TREE_CODE (t
))
11421 case COMPOUND_EXPR
:
11422 if (TREE_SIDE_EFFECTS (TREE_OPERAND (t
, 1)))
11424 t
= TREE_OPERAND (t
, 0);
11428 if (TREE_SIDE_EFFECTS (TREE_OPERAND (t
, 1))
11429 || TREE_SIDE_EFFECTS (TREE_OPERAND (t
, 2)))
11431 t
= TREE_OPERAND (t
, 0);
11444 /* Return the value of VALUE, rounded up to a multiple of DIVISOR.
11445 This can only be applied to objects of a sizetype. */
11448 round_up (tree value
, int divisor
)
11450 tree div
= NULL_TREE
;
11452 gcc_assert (divisor
> 0);
11456 /* See if VALUE is already a multiple of DIVISOR. If so, we don't
11457 have to do anything. Only do this when we are not given a const,
11458 because in that case, this check is more expensive than just
11460 if (TREE_CODE (value
) != INTEGER_CST
)
11462 div
= build_int_cst (TREE_TYPE (value
), divisor
);
11464 if (multiple_of_p (TREE_TYPE (value
), value
, div
))
11468 /* If divisor is a power of two, simplify this to bit manipulation. */
11469 if (divisor
== (divisor
& -divisor
))
11473 t
= build_int_cst (TREE_TYPE (value
), divisor
- 1);
11474 value
= size_binop (PLUS_EXPR
, value
, t
);
11475 t
= build_int_cst (TREE_TYPE (value
), -divisor
);
11476 value
= size_binop (BIT_AND_EXPR
, value
, t
);
11481 div
= build_int_cst (TREE_TYPE (value
), divisor
);
11482 value
= size_binop (CEIL_DIV_EXPR
, value
, div
);
11483 value
= size_binop (MULT_EXPR
, value
, div
);
11489 /* Likewise, but round down. */
11492 round_down (tree value
, int divisor
)
11494 tree div
= NULL_TREE
;
11496 gcc_assert (divisor
> 0);
11500 /* See if VALUE is already a multiple of DIVISOR. If so, we don't
11501 have to do anything. Only do this when we are not given a const,
11502 because in that case, this check is more expensive than just
11504 if (TREE_CODE (value
) != INTEGER_CST
)
11506 div
= build_int_cst (TREE_TYPE (value
), divisor
);
11508 if (multiple_of_p (TREE_TYPE (value
), value
, div
))
11512 /* If divisor is a power of two, simplify this to bit manipulation. */
11513 if (divisor
== (divisor
& -divisor
))
11517 t
= build_int_cst (TREE_TYPE (value
), -divisor
);
11518 value
= size_binop (BIT_AND_EXPR
, value
, t
);
11523 div
= build_int_cst (TREE_TYPE (value
), divisor
);
11524 value
= size_binop (FLOOR_DIV_EXPR
, value
, div
);
11525 value
= size_binop (MULT_EXPR
, value
, div
);
11531 /* Returns the pointer to the base of the object addressed by EXP and
11532 extracts the information about the offset of the access, storing it
11533 to PBITPOS and POFFSET. */
11536 split_address_to_core_and_offset (tree exp
,
11537 HOST_WIDE_INT
*pbitpos
, tree
*poffset
)
11540 enum machine_mode mode
;
11541 int unsignedp
, volatilep
;
11542 HOST_WIDE_INT bitsize
;
11544 if (TREE_CODE (exp
) == ADDR_EXPR
)
11546 core
= get_inner_reference (TREE_OPERAND (exp
, 0), &bitsize
, pbitpos
,
11547 poffset
, &mode
, &unsignedp
, &volatilep
,
11550 if (TREE_CODE (core
) == INDIRECT_REF
)
11551 core
= TREE_OPERAND (core
, 0);
11557 *poffset
= NULL_TREE
;
11563 /* Returns true if addresses of E1 and E2 differ by a constant, false
11564 otherwise. If they do, E1 - E2 is stored in *DIFF. */
11567 ptr_difference_const (tree e1
, tree e2
, HOST_WIDE_INT
*diff
)
11570 HOST_WIDE_INT bitpos1
, bitpos2
;
11571 tree toffset1
, toffset2
, tdiff
, type
;
11573 core1
= split_address_to_core_and_offset (e1
, &bitpos1
, &toffset1
);
11574 core2
= split_address_to_core_and_offset (e2
, &bitpos2
, &toffset2
);
11576 if (bitpos1
% BITS_PER_UNIT
!= 0
11577 || bitpos2
% BITS_PER_UNIT
!= 0
11578 || !operand_equal_p (core1
, core2
, 0))
11581 if (toffset1
&& toffset2
)
11583 type
= TREE_TYPE (toffset1
);
11584 if (type
!= TREE_TYPE (toffset2
))
11585 toffset2
= fold_convert (type
, toffset2
);
11587 tdiff
= fold_build2 (MINUS_EXPR
, type
, toffset1
, toffset2
);
11588 if (!host_integerp (tdiff
, 0))
11591 *diff
= tree_low_cst (tdiff
, 0);
11593 else if (toffset1
|| toffset2
)
11595 /* If only one of the offsets is non-constant, the difference cannot
11602 *diff
+= (bitpos1
- bitpos2
) / BITS_PER_UNIT
;
11606 /* Simplify the floating point expression EXP when the sign of the
11607 result is not significant. Return NULL_TREE if no simplification
11611 fold_strip_sign_ops (tree exp
)
11615 switch (TREE_CODE (exp
))
11619 arg0
= fold_strip_sign_ops (TREE_OPERAND (exp
, 0));
11620 return arg0
? arg0
: TREE_OPERAND (exp
, 0);
11624 if (HONOR_SIGN_DEPENDENT_ROUNDING (TYPE_MODE (TREE_TYPE (exp
))))
11626 arg0
= fold_strip_sign_ops (TREE_OPERAND (exp
, 0));
11627 arg1
= fold_strip_sign_ops (TREE_OPERAND (exp
, 1));
11628 if (arg0
!= NULL_TREE
|| arg1
!= NULL_TREE
)
11629 return fold_build2 (TREE_CODE (exp
), TREE_TYPE (exp
),
11630 arg0
? arg0
: TREE_OPERAND (exp
, 0),
11631 arg1
? arg1
: TREE_OPERAND (exp
, 1));