1 /* Utility routines for data type conversion for GCC.
2 Copyright (C) 1987-2016 Free Software Foundation, Inc.
4 This file is part of GCC.
6 GCC is free software; you can redistribute it and/or modify it under
7 the terms of the GNU General Public License as published by the Free
8 Software Foundation; either version 3, or (at your option) any later
11 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
12 WARRANTY; without even the implied warranty of MERCHANTABILITY or
13 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
16 You should have received a copy of the GNU General Public License
17 along with GCC; see the file COPYING3. If not see
18 <http://www.gnu.org/licenses/>. */
21 /* These routines are somewhat language-independent utility function
22 intended to be called by the language-specific convert () functions. */
26 #include "coretypes.h"
29 #include "diagnostic-core.h"
30 #include "fold-const.h"
31 #include "stor-layout.h"
33 #include "langhooks.h"
37 #define maybe_fold_build1_loc(FOLD_P, LOC, CODE, TYPE, EXPR) \
38 ((FOLD_P) ? fold_build1_loc (LOC, CODE, TYPE, EXPR) \
39 : build1_loc (LOC, CODE, TYPE, EXPR))
40 #define maybe_fold_build2_loc(FOLD_P, LOC, CODE, TYPE, EXPR1, EXPR2) \
41 ((FOLD_P) ? fold_build2_loc (LOC, CODE, TYPE, EXPR1, EXPR2) \
42 : build2_loc (LOC, CODE, TYPE, EXPR1, EXPR2))
44 /* Convert EXPR to some pointer or reference type TYPE.
45 EXPR must be pointer, reference, integer, enumeral, or literal zero;
46 in other cases error is called. If FOLD_P is true, try to fold the
50 convert_to_pointer_1 (tree type
, tree expr
, bool fold_p
)
52 location_t loc
= EXPR_LOCATION (expr
);
53 if (TREE_TYPE (expr
) == type
)
56 switch (TREE_CODE (TREE_TYPE (expr
)))
61 /* If the pointers point to different address spaces, conversion needs
62 to be done via a ADDR_SPACE_CONVERT_EXPR instead of a NOP_EXPR. */
63 addr_space_t to_as
= TYPE_ADDR_SPACE (TREE_TYPE (type
));
64 addr_space_t from_as
= TYPE_ADDR_SPACE (TREE_TYPE (TREE_TYPE (expr
)));
67 return maybe_fold_build1_loc (fold_p
, loc
, NOP_EXPR
, type
, expr
);
69 return maybe_fold_build1_loc (fold_p
, loc
, ADDR_SPACE_CONVERT_EXPR
,
77 /* If the input precision differs from the target pointer type
78 precision, first convert the input expression to an integer type of
79 the target precision. Some targets, e.g. VMS, need several pointer
80 sizes to coexist so the latter isn't necessarily POINTER_SIZE. */
81 unsigned int pprec
= TYPE_PRECISION (type
);
82 unsigned int eprec
= TYPE_PRECISION (TREE_TYPE (expr
));
86 = maybe_fold_build1_loc (fold_p
, loc
, NOP_EXPR
,
87 lang_hooks
.types
.type_for_size (pprec
, 0),
90 return maybe_fold_build1_loc (fold_p
, loc
, CONVERT_EXPR
, type
, expr
);
93 error ("cannot convert to a pointer type");
94 return convert_to_pointer_1 (type
, integer_zero_node
, fold_p
);
98 /* A wrapper around convert_to_pointer_1 that always folds the
102 convert_to_pointer (tree type
, tree expr
)
104 return convert_to_pointer_1 (type
, expr
, true);
107 /* A wrapper around convert_to_pointer_1 that only folds the
108 expression if it is CONSTANT_CLASS_P. */
111 convert_to_pointer_nofold (tree type
, tree expr
)
113 return convert_to_pointer_1 (type
, expr
, CONSTANT_CLASS_P (expr
));
116 /* Convert EXPR to some floating-point type TYPE.
118 EXPR must be float, fixed-point, integer, or enumeral;
119 in other cases error is called. If FOLD_P is true, try to fold
123 convert_to_real_1 (tree type
, tree expr
, bool fold_p
)
125 enum built_in_function fcode
= builtin_mathfn_code (expr
);
126 tree itype
= TREE_TYPE (expr
);
127 location_t loc
= EXPR_LOCATION (expr
);
129 if (TREE_CODE (expr
) == COMPOUND_EXPR
)
131 tree t
= convert_to_real_1 (type
, TREE_OPERAND (expr
, 1), fold_p
);
132 if (t
== TREE_OPERAND (expr
, 1))
134 return build2_loc (EXPR_LOCATION (expr
), COMPOUND_EXPR
, TREE_TYPE (t
),
135 TREE_OPERAND (expr
, 0), t
);
138 /* Disable until we figure out how to decide whether the functions are
139 present in runtime. */
140 /* Convert (float)sqrt((double)x) where x is float into sqrtf(x) */
142 && (TYPE_MODE (type
) == TYPE_MODE (double_type_node
)
143 || TYPE_MODE (type
) == TYPE_MODE (float_type_node
)))
147 #define CASE_MATHFN(FN) case BUILT_IN_##FN: case BUILT_IN_##FN##L:
162 /* The above functions may set errno differently with float
163 input or output so this transformation is not safe with
184 /* The above functions are not safe to do this conversion. */
185 if (!flag_unsafe_math_optimizations
)
192 tree arg0
= strip_float_extensions (CALL_EXPR_ARG (expr
, 0));
195 /* We have (outertype)sqrt((innertype)x). Choose the wider mode from
196 the both as the safe type for operation. */
197 if (TYPE_PRECISION (TREE_TYPE (arg0
)) > TYPE_PRECISION (type
))
198 newtype
= TREE_TYPE (arg0
);
200 /* We consider to convert
202 (T1) sqrtT2 ((T2) exprT3)
204 (T1) sqrtT4 ((T4) exprT3)
206 , where T1 is TYPE, T2 is ITYPE, T3 is TREE_TYPE (ARG0),
207 and T4 is NEWTYPE. All those types are of floating point types.
208 T4 (NEWTYPE) should be narrower than T2 (ITYPE). This conversion
209 is safe only if P1 >= P2*2+2, where P1 and P2 are precisions of
210 T2 and T4. See the following URL for a reference:
211 http://stackoverflow.com/questions/9235456/determining-
212 floating-point-square-root
214 if ((fcode
== BUILT_IN_SQRT
|| fcode
== BUILT_IN_SQRTL
)
215 && !flag_unsafe_math_optimizations
)
217 /* The following conversion is unsafe even the precision condition
220 (float) sqrtl ((long double) double_val) -> (float) sqrt (double_val)
222 if (TYPE_MODE (type
) != TYPE_MODE (newtype
))
225 int p1
= REAL_MODE_FORMAT (TYPE_MODE (itype
))->p
;
226 int p2
= REAL_MODE_FORMAT (TYPE_MODE (newtype
))->p
;
231 /* Be careful about integer to fp conversions.
232 These may overflow still. */
233 if (FLOAT_TYPE_P (TREE_TYPE (arg0
))
234 && TYPE_PRECISION (newtype
) < TYPE_PRECISION (itype
)
235 && (TYPE_MODE (newtype
) == TYPE_MODE (double_type_node
)
236 || TYPE_MODE (newtype
) == TYPE_MODE (float_type_node
)))
238 tree fn
= mathfn_built_in (newtype
, fcode
);
241 tree arg
= convert_to_real_1 (newtype
, arg0
, fold_p
);
242 expr
= build_call_expr (fn
, 1, arg
);
253 /* Propagate the cast into the operation. */
254 if (itype
!= type
&& FLOAT_TYPE_P (type
))
255 switch (TREE_CODE (expr
))
257 /* Convert (float)-x into -(float)x. This is safe for
258 round-to-nearest rounding mode when the inner type is float. */
261 if (!flag_rounding_math
262 && FLOAT_TYPE_P (itype
)
263 && TYPE_PRECISION (type
) < TYPE_PRECISION (itype
))
265 tree arg
= convert_to_real_1 (type
, TREE_OPERAND (expr
, 0),
267 return build1 (TREE_CODE (expr
), type
, arg
);
270 /* Convert (outertype)((innertype0)a+(innertype1)b)
271 into ((newtype)a+(newtype)b) where newtype
272 is the widest mode from all of these. */
278 tree arg0
= strip_float_extensions (TREE_OPERAND (expr
, 0));
279 tree arg1
= strip_float_extensions (TREE_OPERAND (expr
, 1));
281 if (FLOAT_TYPE_P (TREE_TYPE (arg0
))
282 && FLOAT_TYPE_P (TREE_TYPE (arg1
))
283 && DECIMAL_FLOAT_TYPE_P (itype
) == DECIMAL_FLOAT_TYPE_P (type
))
287 if (TYPE_MODE (TREE_TYPE (arg0
)) == SDmode
288 || TYPE_MODE (TREE_TYPE (arg1
)) == SDmode
289 || TYPE_MODE (type
) == SDmode
)
290 newtype
= dfloat32_type_node
;
291 if (TYPE_MODE (TREE_TYPE (arg0
)) == DDmode
292 || TYPE_MODE (TREE_TYPE (arg1
)) == DDmode
293 || TYPE_MODE (type
) == DDmode
)
294 newtype
= dfloat64_type_node
;
295 if (TYPE_MODE (TREE_TYPE (arg0
)) == TDmode
296 || TYPE_MODE (TREE_TYPE (arg1
)) == TDmode
297 || TYPE_MODE (type
) == TDmode
)
298 newtype
= dfloat128_type_node
;
299 if (newtype
== dfloat32_type_node
300 || newtype
== dfloat64_type_node
301 || newtype
== dfloat128_type_node
)
303 expr
= build2 (TREE_CODE (expr
), newtype
,
304 convert_to_real_1 (newtype
, arg0
,
306 convert_to_real_1 (newtype
, arg1
,
313 if (TYPE_PRECISION (TREE_TYPE (arg0
)) > TYPE_PRECISION (newtype
))
314 newtype
= TREE_TYPE (arg0
);
315 if (TYPE_PRECISION (TREE_TYPE (arg1
)) > TYPE_PRECISION (newtype
))
316 newtype
= TREE_TYPE (arg1
);
317 /* Sometimes this transformation is safe (cannot
318 change results through affecting double rounding
319 cases) and sometimes it is not. If NEWTYPE is
320 wider than TYPE, e.g. (float)((long double)double
321 + (long double)double) converted to
322 (float)(double + double), the transformation is
323 unsafe regardless of the details of the types
324 involved; double rounding can arise if the result
325 of NEWTYPE arithmetic is a NEWTYPE value half way
326 between two representable TYPE values but the
327 exact value is sufficiently different (in the
328 right direction) for this difference to be
329 visible in ITYPE arithmetic. If NEWTYPE is the
330 same as TYPE, however, the transformation may be
331 safe depending on the types involved: it is safe
332 if the ITYPE has strictly more than twice as many
333 mantissa bits as TYPE, can represent infinities
334 and NaNs if the TYPE can, and has sufficient
335 exponent range for the product or ratio of two
336 values representable in the TYPE to be within the
337 range of normal values of ITYPE. */
338 if (TYPE_PRECISION (newtype
) < TYPE_PRECISION (itype
)
339 && (flag_unsafe_math_optimizations
340 || (TYPE_PRECISION (newtype
) == TYPE_PRECISION (type
)
341 && real_can_shorten_arithmetic (TYPE_MODE (itype
),
343 && !excess_precision_type (newtype
))))
345 expr
= build2 (TREE_CODE (expr
), newtype
,
346 convert_to_real_1 (newtype
, arg0
,
348 convert_to_real_1 (newtype
, arg1
,
360 switch (TREE_CODE (TREE_TYPE (expr
)))
363 /* Ignore the conversion if we don't need to store intermediate
364 results and neither type is a decimal float. */
365 return build1_loc (loc
,
367 || DECIMAL_FLOAT_TYPE_P (type
)
368 || DECIMAL_FLOAT_TYPE_P (itype
))
369 ? CONVERT_EXPR
: NOP_EXPR
, type
, expr
);
374 return build1 (FLOAT_EXPR
, type
, expr
);
376 case FIXED_POINT_TYPE
:
377 return build1 (FIXED_CONVERT_EXPR
, type
, expr
);
380 return convert (type
,
381 maybe_fold_build1_loc (fold_p
, loc
, REALPART_EXPR
,
382 TREE_TYPE (TREE_TYPE (expr
)),
387 error ("pointer value used where a floating point value was expected");
388 return convert_to_real_1 (type
, integer_zero_node
, fold_p
);
391 error ("aggregate value used where a float was expected");
392 return convert_to_real_1 (type
, integer_zero_node
, fold_p
);
396 /* A wrapper around convert_to_real_1 that always folds the
400 convert_to_real (tree type
, tree expr
)
402 return convert_to_real_1 (type
, expr
, true);
405 /* A wrapper around convert_to_real_1 that only folds the
406 expression if it is CONSTANT_CLASS_P. */
409 convert_to_real_nofold (tree type
, tree expr
)
411 return convert_to_real_1 (type
, expr
, CONSTANT_CLASS_P (expr
));
414 /* Convert EXPR to some integer (or enum) type TYPE.
416 EXPR must be pointer, integer, discrete (enum, char, or bool), float,
417 fixed-point or vector; in other cases error is called.
419 If DOFOLD is TRUE, we try to simplify newly-created patterns by folding.
421 The result of this is always supposed to be a newly created tree node
422 not in use in any existing structure. */
425 convert_to_integer_1 (tree type
, tree expr
, bool dofold
)
427 enum tree_code ex_form
= TREE_CODE (expr
);
428 tree intype
= TREE_TYPE (expr
);
429 unsigned int inprec
= element_precision (intype
);
430 unsigned int outprec
= element_precision (type
);
431 location_t loc
= EXPR_LOCATION (expr
);
433 /* An INTEGER_TYPE cannot be incomplete, but an ENUMERAL_TYPE can
434 be. Consider `enum E = { a, b = (enum E) 3 };'. */
435 if (!COMPLETE_TYPE_P (type
))
437 error ("conversion to incomplete type");
438 return error_mark_node
;
441 if (ex_form
== COMPOUND_EXPR
)
443 tree t
= convert_to_integer_1 (type
, TREE_OPERAND (expr
, 1), dofold
);
444 if (t
== TREE_OPERAND (expr
, 1))
446 return build2_loc (EXPR_LOCATION (expr
), COMPOUND_EXPR
, TREE_TYPE (t
),
447 TREE_OPERAND (expr
, 0), t
);
450 /* Convert e.g. (long)round(d) -> lround(d). */
451 /* If we're converting to char, we may encounter differing behavior
452 between converting from double->char vs double->long->char.
453 We're in "undefined" territory but we prefer to be conservative,
454 so only proceed in "unsafe" math mode. */
456 && (flag_unsafe_math_optimizations
457 || (long_integer_type_node
458 && outprec
>= TYPE_PRECISION (long_integer_type_node
))))
460 tree s_expr
= strip_float_extensions (expr
);
461 tree s_intype
= TREE_TYPE (s_expr
);
462 const enum built_in_function fcode
= builtin_mathfn_code (s_expr
);
467 CASE_FLT_FN (BUILT_IN_CEIL
):
468 /* Only convert in ISO C99 mode. */
469 if (!targetm
.libc_has_function (function_c99_misc
))
471 if (outprec
< TYPE_PRECISION (integer_type_node
)
472 || (outprec
== TYPE_PRECISION (integer_type_node
)
473 && !TYPE_UNSIGNED (type
)))
474 fn
= mathfn_built_in (s_intype
, BUILT_IN_ICEIL
);
475 else if (outprec
== TYPE_PRECISION (long_integer_type_node
)
476 && !TYPE_UNSIGNED (type
))
477 fn
= mathfn_built_in (s_intype
, BUILT_IN_LCEIL
);
478 else if (outprec
== TYPE_PRECISION (long_long_integer_type_node
)
479 && !TYPE_UNSIGNED (type
))
480 fn
= mathfn_built_in (s_intype
, BUILT_IN_LLCEIL
);
483 CASE_FLT_FN (BUILT_IN_FLOOR
):
484 /* Only convert in ISO C99 mode. */
485 if (!targetm
.libc_has_function (function_c99_misc
))
487 if (outprec
< TYPE_PRECISION (integer_type_node
)
488 || (outprec
== TYPE_PRECISION (integer_type_node
)
489 && !TYPE_UNSIGNED (type
)))
490 fn
= mathfn_built_in (s_intype
, BUILT_IN_IFLOOR
);
491 else if (outprec
== TYPE_PRECISION (long_integer_type_node
)
492 && !TYPE_UNSIGNED (type
))
493 fn
= mathfn_built_in (s_intype
, BUILT_IN_LFLOOR
);
494 else if (outprec
== TYPE_PRECISION (long_long_integer_type_node
)
495 && !TYPE_UNSIGNED (type
))
496 fn
= mathfn_built_in (s_intype
, BUILT_IN_LLFLOOR
);
499 CASE_FLT_FN (BUILT_IN_ROUND
):
500 /* Only convert in ISO C99 mode and with -fno-math-errno. */
501 if (!targetm
.libc_has_function (function_c99_misc
) || flag_errno_math
)
503 if (outprec
< TYPE_PRECISION (integer_type_node
)
504 || (outprec
== TYPE_PRECISION (integer_type_node
)
505 && !TYPE_UNSIGNED (type
)))
506 fn
= mathfn_built_in (s_intype
, BUILT_IN_IROUND
);
507 else if (outprec
== TYPE_PRECISION (long_integer_type_node
)
508 && !TYPE_UNSIGNED (type
))
509 fn
= mathfn_built_in (s_intype
, BUILT_IN_LROUND
);
510 else if (outprec
== TYPE_PRECISION (long_long_integer_type_node
)
511 && !TYPE_UNSIGNED (type
))
512 fn
= mathfn_built_in (s_intype
, BUILT_IN_LLROUND
);
515 CASE_FLT_FN (BUILT_IN_NEARBYINT
):
516 /* Only convert nearbyint* if we can ignore math exceptions. */
517 if (flag_trapping_math
)
519 /* ... Fall through ... */
520 CASE_FLT_FN (BUILT_IN_RINT
):
521 /* Only convert in ISO C99 mode and with -fno-math-errno. */
522 if (!targetm
.libc_has_function (function_c99_misc
) || flag_errno_math
)
524 if (outprec
< TYPE_PRECISION (integer_type_node
)
525 || (outprec
== TYPE_PRECISION (integer_type_node
)
526 && !TYPE_UNSIGNED (type
)))
527 fn
= mathfn_built_in (s_intype
, BUILT_IN_IRINT
);
528 else if (outprec
== TYPE_PRECISION (long_integer_type_node
)
529 && !TYPE_UNSIGNED (type
))
530 fn
= mathfn_built_in (s_intype
, BUILT_IN_LRINT
);
531 else if (outprec
== TYPE_PRECISION (long_long_integer_type_node
)
532 && !TYPE_UNSIGNED (type
))
533 fn
= mathfn_built_in (s_intype
, BUILT_IN_LLRINT
);
536 CASE_FLT_FN (BUILT_IN_TRUNC
):
537 return convert_to_integer_1 (type
, CALL_EXPR_ARG (s_expr
, 0), dofold
);
545 tree newexpr
= build_call_expr (fn
, 1, CALL_EXPR_ARG (s_expr
, 0));
546 return convert_to_integer_1 (type
, newexpr
, dofold
);
550 /* Convert (int)logb(d) -> ilogb(d). */
552 && flag_unsafe_math_optimizations
553 && !flag_trapping_math
&& !flag_errno_math
&& flag_finite_math_only
555 && (outprec
> TYPE_PRECISION (integer_type_node
)
556 || (outprec
== TYPE_PRECISION (integer_type_node
)
557 && !TYPE_UNSIGNED (type
))))
559 tree s_expr
= strip_float_extensions (expr
);
560 tree s_intype
= TREE_TYPE (s_expr
);
561 const enum built_in_function fcode
= builtin_mathfn_code (s_expr
);
566 CASE_FLT_FN (BUILT_IN_LOGB
):
567 fn
= mathfn_built_in (s_intype
, BUILT_IN_ILOGB
);
576 tree newexpr
= build_call_expr (fn
, 1, CALL_EXPR_ARG (s_expr
, 0));
577 return convert_to_integer_1 (type
, newexpr
, dofold
);
581 switch (TREE_CODE (intype
))
585 if (integer_zerop (expr
))
586 return build_int_cst (type
, 0);
588 /* Convert to an unsigned integer of the correct width first, and from
589 there widen/truncate to the required type. Some targets support the
590 coexistence of multiple valid pointer sizes, so fetch the one we need
593 return build1 (CONVERT_EXPR
, type
, expr
);
594 expr
= fold_build1 (CONVERT_EXPR
,
595 lang_hooks
.types
.type_for_size
596 (TYPE_PRECISION (intype
), 0),
598 return fold_convert (type
, expr
);
604 /* If this is a logical operation, which just returns 0 or 1, we can
605 change the type of the expression. */
607 if (TREE_CODE_CLASS (ex_form
) == tcc_comparison
)
609 expr
= copy_node (expr
);
610 TREE_TYPE (expr
) = type
;
614 /* If we are widening the type, put in an explicit conversion.
615 Similarly if we are not changing the width. After this, we know
616 we are truncating EXPR. */
618 else if (outprec
>= inprec
)
622 /* If the precision of the EXPR's type is K bits and the
623 destination mode has more bits, and the sign is changing,
624 it is not safe to use a NOP_EXPR. For example, suppose
625 that EXPR's type is a 3-bit unsigned integer type, the
626 TYPE is a 3-bit signed integer type, and the machine mode
627 for the types is 8-bit QImode. In that case, the
628 conversion necessitates an explicit sign-extension. In
629 the signed-to-unsigned case the high-order bits have to
631 if (TYPE_UNSIGNED (type
) != TYPE_UNSIGNED (TREE_TYPE (expr
))
632 && (TYPE_PRECISION (TREE_TYPE (expr
))
633 != GET_MODE_PRECISION (TYPE_MODE (TREE_TYPE (expr
)))))
638 return maybe_fold_build1_loc (dofold
, loc
, code
, type
, expr
);
641 /* If TYPE is an enumeral type or a type with a precision less
642 than the number of bits in its mode, do the conversion to the
643 type corresponding to its mode, then do a nop conversion
645 else if (TREE_CODE (type
) == ENUMERAL_TYPE
646 || outprec
!= GET_MODE_PRECISION (TYPE_MODE (type
)))
647 return build1 (NOP_EXPR
, type
,
648 convert (lang_hooks
.types
.type_for_mode
649 (TYPE_MODE (type
), TYPE_UNSIGNED (type
)),
652 /* Here detect when we can distribute the truncation down past some
653 arithmetic. For example, if adding two longs and converting to an
654 int, we can equally well convert both to ints and then add.
655 For the operations handled here, such truncation distribution
657 It is desirable in these cases:
658 1) when truncating down to full-word from a larger size
659 2) when truncating takes no work.
660 3) when at least one operand of the arithmetic has been extended
661 (as by C's default conversions). In this case we need two conversions
662 if we do the arithmetic as already requested, so we might as well
663 truncate both and then combine. Perhaps that way we need only one.
665 Note that in general we cannot do the arithmetic in a type
666 shorter than the desired result of conversion, even if the operands
667 are both extended from a shorter type, because they might overflow
668 if combined in that type. The exceptions to this--the times when
669 two narrow values can be combined in their narrow type even to
670 make a wider result--are handled by "shorten" in build_binary_op. */
675 /* We can pass truncation down through right shifting
676 when the shift count is a nonpositive constant. */
677 if (TREE_CODE (TREE_OPERAND (expr
, 1)) == INTEGER_CST
678 && tree_int_cst_sgn (TREE_OPERAND (expr
, 1)) <= 0)
683 /* We can pass truncation down through left shifting
684 when the shift count is a nonnegative constant and
685 the target type is unsigned. */
686 if (TREE_CODE (TREE_OPERAND (expr
, 1)) == INTEGER_CST
687 && tree_int_cst_sgn (TREE_OPERAND (expr
, 1)) >= 0
688 && TYPE_UNSIGNED (type
)
689 && TREE_CODE (TYPE_SIZE (type
)) == INTEGER_CST
)
691 /* If shift count is less than the width of the truncated type,
693 if (tree_int_cst_lt (TREE_OPERAND (expr
, 1), TYPE_SIZE (type
)))
694 /* In this case, shifting is like multiplication. */
698 /* If it is >= that width, result is zero.
699 Handling this with trunc1 would give the wrong result:
700 (int) ((long long) a << 32) is well defined (as 0)
701 but (int) a << 32 is undefined and would get a
704 tree t
= build_int_cst (type
, 0);
706 /* If the original expression had side-effects, we must
708 if (TREE_SIDE_EFFECTS (expr
))
709 return build2 (COMPOUND_EXPR
, type
, expr
, t
);
718 tree arg0
= get_unwidened (TREE_OPERAND (expr
, 0), type
);
719 tree arg1
= get_unwidened (TREE_OPERAND (expr
, 1), type
);
721 /* Don't distribute unless the output precision is at least as big
722 as the actual inputs and it has the same signedness. */
723 if (outprec
>= TYPE_PRECISION (TREE_TYPE (arg0
))
724 && outprec
>= TYPE_PRECISION (TREE_TYPE (arg1
))
725 /* If signedness of arg0 and arg1 don't match,
726 we can't necessarily find a type to compare them in. */
727 && (TYPE_UNSIGNED (TREE_TYPE (arg0
))
728 == TYPE_UNSIGNED (TREE_TYPE (arg1
)))
729 /* Do not change the sign of the division. */
730 && (TYPE_UNSIGNED (TREE_TYPE (expr
))
731 == TYPE_UNSIGNED (TREE_TYPE (arg0
)))
732 /* Either require unsigned division or a division by
733 a constant that is not -1. */
734 && (TYPE_UNSIGNED (TREE_TYPE (arg0
))
735 || (TREE_CODE (arg1
) == INTEGER_CST
736 && !integer_all_onesp (arg1
))))
745 tree arg0
= get_unwidened (TREE_OPERAND (expr
, 0), type
);
746 tree arg1
= get_unwidened (TREE_OPERAND (expr
, 1), type
);
748 /* Don't distribute unless the output precision is at least as big
749 as the actual inputs. Otherwise, the comparison of the
750 truncated values will be wrong. */
751 if (outprec
>= TYPE_PRECISION (TREE_TYPE (arg0
))
752 && outprec
>= TYPE_PRECISION (TREE_TYPE (arg1
))
753 /* If signedness of arg0 and arg1 don't match,
754 we can't necessarily find a type to compare them in. */
755 && (TYPE_UNSIGNED (TREE_TYPE (arg0
))
756 == TYPE_UNSIGNED (TREE_TYPE (arg1
))))
768 tree arg0
= get_unwidened (TREE_OPERAND (expr
, 0), type
);
769 tree arg1
= get_unwidened (TREE_OPERAND (expr
, 1), type
);
771 /* Do not try to narrow operands of pointer subtraction;
772 that will interfere with other folding. */
773 if (ex_form
== MINUS_EXPR
774 && CONVERT_EXPR_P (arg0
)
775 && CONVERT_EXPR_P (arg1
)
776 && POINTER_TYPE_P (TREE_TYPE (TREE_OPERAND (arg0
, 0)))
777 && POINTER_TYPE_P (TREE_TYPE (TREE_OPERAND (arg1
, 0))))
780 if (outprec
>= BITS_PER_WORD
781 || TRULY_NOOP_TRUNCATION (outprec
, inprec
)
782 || inprec
> TYPE_PRECISION (TREE_TYPE (arg0
))
783 || inprec
> TYPE_PRECISION (TREE_TYPE (arg1
)))
785 /* Do the arithmetic in type TYPEX,
786 then convert result to TYPE. */
789 /* Can't do arithmetic in enumeral types
790 so use an integer type that will hold the values. */
791 if (TREE_CODE (typex
) == ENUMERAL_TYPE
)
793 = lang_hooks
.types
.type_for_size (TYPE_PRECISION (typex
),
794 TYPE_UNSIGNED (typex
));
796 /* But now perhaps TYPEX is as wide as INPREC.
797 In that case, do nothing special here.
798 (Otherwise would recurse infinitely in convert. */
799 if (TYPE_PRECISION (typex
) != inprec
)
801 /* Don't do unsigned arithmetic where signed was wanted,
803 Exception: if both of the original operands were
804 unsigned then we can safely do the work as unsigned.
805 Exception: shift operations take their type solely
806 from the first argument.
807 Exception: the LSHIFT_EXPR case above requires that
808 we perform this operation unsigned lest we produce
809 signed-overflow undefinedness.
810 And we may need to do it as unsigned
811 if we truncate to the original size. */
812 if (TYPE_UNSIGNED (TREE_TYPE (expr
))
813 || (TYPE_UNSIGNED (TREE_TYPE (arg0
))
814 && (TYPE_UNSIGNED (TREE_TYPE (arg1
))
815 || ex_form
== LSHIFT_EXPR
816 || ex_form
== RSHIFT_EXPR
817 || ex_form
== LROTATE_EXPR
818 || ex_form
== RROTATE_EXPR
))
819 || ex_form
== LSHIFT_EXPR
820 /* If we have !flag_wrapv, and either ARG0 or
821 ARG1 is of a signed type, we have to do
822 PLUS_EXPR, MINUS_EXPR or MULT_EXPR in an unsigned
823 type in case the operation in outprec precision
824 could overflow. Otherwise, we would introduce
825 signed-overflow undefinedness. */
826 || ((!TYPE_OVERFLOW_WRAPS (TREE_TYPE (arg0
))
827 || !TYPE_OVERFLOW_WRAPS (TREE_TYPE (arg1
)))
828 && ((TYPE_PRECISION (TREE_TYPE (arg0
)) * 2u
830 || (TYPE_PRECISION (TREE_TYPE (arg1
)) * 2u
832 && (ex_form
== PLUS_EXPR
833 || ex_form
== MINUS_EXPR
834 || ex_form
== MULT_EXPR
)))
836 if (!TYPE_UNSIGNED (typex
))
837 typex
= unsigned_type_for (typex
);
841 if (TYPE_UNSIGNED (typex
))
842 typex
= signed_type_for (typex
);
844 /* We should do away with all this once we have a proper
845 type promotion/demotion pass, see PR45397. */
846 expr
= maybe_fold_build2_loc (dofold
, loc
, ex_form
, typex
,
847 convert (typex
, arg0
),
848 convert (typex
, arg1
));
849 return convert (type
, expr
);
857 /* This is not correct for ABS_EXPR,
858 since we must test the sign before truncation. */
863 /* Do the arithmetic in type TYPEX,
864 then convert result to TYPE. */
867 /* Can't do arithmetic in enumeral types
868 so use an integer type that will hold the values. */
869 if (TREE_CODE (typex
) == ENUMERAL_TYPE
)
871 = lang_hooks
.types
.type_for_size (TYPE_PRECISION (typex
),
872 TYPE_UNSIGNED (typex
));
874 if (!TYPE_UNSIGNED (typex
))
875 typex
= unsigned_type_for (typex
);
876 return convert (type
,
877 fold_build1 (ex_form
, typex
,
879 TREE_OPERAND (expr
, 0))));
884 "can't convert between vector values of different size" error. */
885 if (TREE_CODE (TREE_TYPE (TREE_OPERAND (expr
, 0))) == VECTOR_TYPE
886 && (GET_MODE_SIZE (TYPE_MODE (TREE_TYPE (TREE_OPERAND (expr
, 0))))
887 != GET_MODE_SIZE (TYPE_MODE (type
))))
889 /* If truncating after truncating, might as well do all at once.
890 If truncating after extending, we may get rid of wasted work. */
891 return convert (type
, get_unwidened (TREE_OPERAND (expr
, 0), type
));
894 /* It is sometimes worthwhile to push the narrowing down through
895 the conditional and never loses. A COND_EXPR may have a throw
896 as one operand, which then has void type. Just leave void
897 operands as they are. */
900 fold_build3 (COND_EXPR
, type
, TREE_OPERAND (expr
, 0),
901 VOID_TYPE_P (TREE_TYPE (TREE_OPERAND (expr
, 1)))
902 ? TREE_OPERAND (expr
, 1)
903 : convert (type
, TREE_OPERAND (expr
, 1)),
904 VOID_TYPE_P (TREE_TYPE (TREE_OPERAND (expr
, 2)))
905 ? TREE_OPERAND (expr
, 2)
906 : convert (type
, TREE_OPERAND (expr
, 2)));
912 /* When parsing long initializers, we might end up with a lot of casts.
914 if (TREE_CODE (expr
) == INTEGER_CST
)
915 return fold_convert (type
, expr
);
916 return build1 (CONVERT_EXPR
, type
, expr
);
919 if (flag_sanitize
& SANITIZE_FLOAT_CAST
920 && do_ubsan_in_current_function ())
922 expr
= save_expr (expr
);
923 tree check
= ubsan_instrument_float_cast (loc
, type
, expr
);
924 expr
= build1 (FIX_TRUNC_EXPR
, type
, expr
);
925 if (check
== NULL_TREE
)
927 return maybe_fold_build2_loc (dofold
, loc
, COMPOUND_EXPR
,
928 TREE_TYPE (expr
), check
, expr
);
931 return build1 (FIX_TRUNC_EXPR
, type
, expr
);
933 case FIXED_POINT_TYPE
:
934 return build1 (FIXED_CONVERT_EXPR
, type
, expr
);
937 expr
= maybe_fold_build1_loc (dofold
, loc
, REALPART_EXPR
,
938 TREE_TYPE (TREE_TYPE (expr
)), expr
);
939 return convert (type
, expr
);
942 if (!tree_int_cst_equal (TYPE_SIZE (type
), TYPE_SIZE (TREE_TYPE (expr
))))
944 error ("can%'t convert a vector of type %qT"
945 " to type %qT which has different size",
946 TREE_TYPE (expr
), type
);
947 return error_mark_node
;
949 return build1 (VIEW_CONVERT_EXPR
, type
, expr
);
952 error ("aggregate value used where an integer was expected");
953 return convert (type
, integer_zero_node
);
957 /* Convert EXPR to some integer (or enum) type TYPE.
959 EXPR must be pointer, integer, discrete (enum, char, or bool), float,
960 fixed-point or vector; in other cases error is called.
962 The result of this is always supposed to be a newly created tree node
963 not in use in any existing structure. */
966 convert_to_integer (tree type
, tree expr
)
968 return convert_to_integer_1 (type
, expr
, true);
971 /* Convert EXPR to some integer (or enum) type TYPE.
973 EXPR must be pointer, integer, discrete (enum, char, or bool), float,
974 fixed-point or vector; in other cases error is called.
976 The result of this is always supposed to be a newly created tree node
977 not in use in any existing structure. The tree node isn't folded,
978 beside EXPR is of constant class. */
981 convert_to_integer_nofold (tree type
, tree expr
)
983 return convert_to_integer_1 (type
, expr
, CONSTANT_CLASS_P (expr
));
986 /* Convert EXPR to the complex type TYPE in the usual ways. If FOLD_P is
987 true, try to fold the expression. */
990 convert_to_complex_1 (tree type
, tree expr
, bool fold_p
)
992 location_t loc
= EXPR_LOCATION (expr
);
993 tree subtype
= TREE_TYPE (type
);
995 switch (TREE_CODE (TREE_TYPE (expr
)))
998 case FIXED_POINT_TYPE
:
1002 return build2 (COMPLEX_EXPR
, type
, convert (subtype
, expr
),
1003 convert (subtype
, integer_zero_node
));
1007 tree elt_type
= TREE_TYPE (TREE_TYPE (expr
));
1009 if (TYPE_MAIN_VARIANT (elt_type
) == TYPE_MAIN_VARIANT (subtype
))
1011 else if (TREE_CODE (expr
) == COMPOUND_EXPR
)
1013 tree t
= convert_to_complex_1 (type
, TREE_OPERAND (expr
, 1),
1015 if (t
== TREE_OPERAND (expr
, 1))
1017 return build2_loc (EXPR_LOCATION (expr
), COMPOUND_EXPR
,
1018 TREE_TYPE (t
), TREE_OPERAND (expr
, 0), t
);
1020 else if (TREE_CODE (expr
) == COMPLEX_EXPR
)
1021 return maybe_fold_build2_loc (fold_p
, loc
, COMPLEX_EXPR
, type
,
1023 TREE_OPERAND (expr
, 0)),
1025 TREE_OPERAND (expr
, 1)));
1028 expr
= save_expr (expr
);
1029 tree realp
= maybe_fold_build1_loc (fold_p
, loc
, REALPART_EXPR
,
1030 TREE_TYPE (TREE_TYPE (expr
)),
1032 tree imagp
= maybe_fold_build1_loc (fold_p
, loc
, IMAGPART_EXPR
,
1033 TREE_TYPE (TREE_TYPE (expr
)),
1035 return maybe_fold_build2_loc (fold_p
, loc
, COMPLEX_EXPR
, type
,
1036 convert (subtype
, realp
),
1037 convert (subtype
, imagp
));
1042 case REFERENCE_TYPE
:
1043 error ("pointer value used where a complex was expected");
1044 return convert_to_complex_1 (type
, integer_zero_node
, fold_p
);
1047 error ("aggregate value used where a complex was expected");
1048 return convert_to_complex_1 (type
, integer_zero_node
, fold_p
);
1052 /* A wrapper around convert_to_complex_1 that always folds the
1056 convert_to_complex (tree type
, tree expr
)
1058 return convert_to_complex_1 (type
, expr
, true);
1061 /* A wrapper around convert_to_complex_1 that only folds the
1062 expression if it is CONSTANT_CLASS_P. */
1065 convert_to_complex_nofold (tree type
, tree expr
)
1067 return convert_to_complex_1 (type
, expr
, CONSTANT_CLASS_P (expr
));
1070 /* Convert EXPR to the vector type TYPE in the usual ways. */
1073 convert_to_vector (tree type
, tree expr
)
1075 switch (TREE_CODE (TREE_TYPE (expr
)))
1079 if (!tree_int_cst_equal (TYPE_SIZE (type
), TYPE_SIZE (TREE_TYPE (expr
))))
1081 error ("can%'t convert a value of type %qT"
1082 " to vector type %qT which has different size",
1083 TREE_TYPE (expr
), type
);
1084 return error_mark_node
;
1086 return build1 (VIEW_CONVERT_EXPR
, type
, expr
);
1089 error ("can%'t convert value to a vector");
1090 return error_mark_node
;
1094 /* Convert EXPR to some fixed-point type TYPE.
1096 EXPR must be fixed-point, float, integer, or enumeral;
1097 in other cases error is called. */
1100 convert_to_fixed (tree type
, tree expr
)
1102 if (integer_zerop (expr
))
1104 tree fixed_zero_node
= build_fixed (type
, FCONST0 (TYPE_MODE (type
)));
1105 return fixed_zero_node
;
1107 else if (integer_onep (expr
) && ALL_SCALAR_ACCUM_MODE_P (TYPE_MODE (type
)))
1109 tree fixed_one_node
= build_fixed (type
, FCONST1 (TYPE_MODE (type
)));
1110 return fixed_one_node
;
1113 switch (TREE_CODE (TREE_TYPE (expr
)))
1115 case FIXED_POINT_TYPE
:
1120 return build1 (FIXED_CONVERT_EXPR
, type
, expr
);
1123 return convert (type
,
1124 fold_build1 (REALPART_EXPR
,
1125 TREE_TYPE (TREE_TYPE (expr
)), expr
));
1128 error ("aggregate value used where a fixed-point was expected");
1129 return error_mark_node
;