1 /* Fold a constant sub-tree into a single node for C-compiler
2 Copyright (C) 1987, 1988, 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999,
3 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008
4 Free Software Foundation, Inc.
6 This file is part of GCC.
8 GCC is free software; you can redistribute it and/or modify it under
9 the terms of the GNU General Public License as published by the Free
10 Software Foundation; either version 3, or (at your option) any later
13 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
14 WARRANTY; without even the implied warranty of MERCHANTABILITY or
15 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
18 You should have received a copy of the GNU General Public License
19 along with GCC; see the file COPYING3. If not see
20 <http://www.gnu.org/licenses/>. */
22 /*@@ This file should be rewritten to use an arbitrary precision
23 @@ representation for "struct tree_int_cst" and "struct tree_real_cst".
24 @@ Perhaps the routines could also be used for bc/dc, and made a lib.
25 @@ The routines that translate from the ap rep should
26 @@ warn if precision et. al. is lost.
27 @@ This would also make life easier when this technology is used
28 @@ for cross-compilers. */
30 /* The entry points in this file are fold, size_int_wide, size_binop
31 and force_fit_type_double.
33 fold takes a tree as argument and returns a simplified tree.
35 size_binop takes a tree code for an arithmetic operation
36 and two operands that are trees, and produces a tree for the
37 result, assuming the type comes from `sizetype'.
39 size_int takes an integer value, and creates a tree constant
40 with type from `sizetype'.
42 force_fit_type_double takes a constant, an overflowable flag and a
43 prior overflow indicator. It forces the value to fit the type and
46 Note: Since the folders get called on non-gimple code as well as
47 gimple code, we need to handle GIMPLE tuples as well as their
48 corresponding tree equivalents. */
52 #include "coretypes.h"
57 #include "fixed-value.h"
66 #include "langhooks.h"
70 /* Nonzero if we are folding constants inside an initializer; zero
72 int folding_initializer = 0;
74 /* The following constants represent a bit based encoding of GCC's
75 comparison operators. This encoding simplifies transformations
76 on relational comparison operators, such as AND and OR. */
77 enum comparison_code {
96 static void encode (HOST_WIDE_INT *, unsigned HOST_WIDE_INT, HOST_WIDE_INT);
97 static void decode (HOST_WIDE_INT *, unsigned HOST_WIDE_INT *, HOST_WIDE_INT *);
98 static bool negate_mathfn_p (enum built_in_function);
99 static bool negate_expr_p (tree);
100 static tree negate_expr (tree);
101 static tree split_tree (tree, enum tree_code, tree *, tree *, tree *, int);
102 static tree associate_trees (tree, tree, enum tree_code, tree);
103 static tree const_binop (enum tree_code, tree, tree, int);
104 static enum comparison_code comparison_to_compcode (enum tree_code);
105 static enum tree_code compcode_to_comparison (enum comparison_code);
106 static tree combine_comparisons (enum tree_code, enum tree_code,
107 enum tree_code, tree, tree, tree);
108 static int operand_equal_for_comparison_p (tree, tree, tree);
109 static int twoval_comparison_p (tree, tree *, tree *, int *);
110 static tree eval_subst (tree, tree, tree, tree, tree);
111 static tree pedantic_omit_one_operand (tree, tree, tree);
112 static tree distribute_bit_expr (enum tree_code, tree, tree, tree);
113 static tree make_bit_field_ref (tree, tree, HOST_WIDE_INT, HOST_WIDE_INT, int);
114 static tree optimize_bit_field_compare (enum tree_code, tree, tree, tree);
115 static tree decode_field_reference (tree, HOST_WIDE_INT *, HOST_WIDE_INT *,
116 enum machine_mode *, int *, int *,
118 static int all_ones_mask_p (const_tree, int);
119 static tree sign_bit_p (tree, const_tree);
120 static int simple_operand_p (const_tree);
121 static tree range_binop (enum tree_code, tree, tree, int, tree, int);
122 static tree range_predecessor (tree);
123 static tree range_successor (tree);
124 static tree make_range (tree, int *, tree *, tree *, bool *);
125 static tree build_range_check (tree, tree, int, tree, tree);
126 static int merge_ranges (int *, tree *, tree *, int, tree, tree, int, tree,
128 static tree fold_range_test (enum tree_code, tree, tree, tree);
129 static tree fold_cond_expr_with_comparison (tree, tree, tree, tree);
130 static tree unextend (tree, int, int, tree);
131 static tree fold_truthop (enum tree_code, tree, tree, tree);
132 static tree optimize_minmax_comparison (enum tree_code, tree, tree, tree);
133 static tree extract_muldiv (tree, tree, enum tree_code, tree, bool *);
134 static tree extract_muldiv_1 (tree, tree, enum tree_code, tree, bool *);
135 static tree fold_binary_op_with_conditional_arg (enum tree_code, tree,
138 static tree fold_mathfn_compare (enum built_in_function, enum tree_code,
140 static tree fold_inf_compare (enum tree_code, tree, tree, tree);
141 static tree fold_div_compare (enum tree_code, tree, tree, tree);
142 static bool reorder_operands_p (const_tree, const_tree);
143 static tree fold_negate_const (tree, tree);
144 static tree fold_not_const (tree, tree);
145 static tree fold_relational_const (enum tree_code, tree, tree, tree);
148 /* We know that A1 + B1 = SUM1, using 2's complement arithmetic and ignoring
149 overflow. Suppose A, B and SUM have the same respective signs as A1, B1,
150 and SUM1. Then this yields nonzero if overflow occurred during the
153 Overflow occurs if A and B have the same sign, but A and SUM differ in
154 sign. Use `^' to test whether signs differ, and `< 0' to isolate the
156 #define OVERFLOW_SUM_SIGN(a, b, sum) ((~((a) ^ (b)) & ((a) ^ (sum))) < 0)
158 /* To do constant folding on INTEGER_CST nodes requires two-word arithmetic.
159 We do that by representing the two-word integer in 4 words, with only
160 HOST_BITS_PER_WIDE_INT / 2 bits stored in each word, as a positive
161 number. The value of the word is LOWPART + HIGHPART * BASE. */
164 ((x) & (((unsigned HOST_WIDE_INT) 1 << (HOST_BITS_PER_WIDE_INT / 2)) - 1))
165 #define HIGHPART(x) \
166 ((unsigned HOST_WIDE_INT) (x) >> HOST_BITS_PER_WIDE_INT / 2)
167 #define BASE ((unsigned HOST_WIDE_INT) 1 << HOST_BITS_PER_WIDE_INT / 2)
169 /* Unpack a two-word integer into 4 words.
170 LOW and HI are the integer, as two `HOST_WIDE_INT' pieces.
171 WORDS points to the array of HOST_WIDE_INTs. */
174 encode (HOST_WIDE_INT *words, unsigned HOST_WIDE_INT low, HOST_WIDE_INT hi)
176 words[0] = LOWPART (low);
177 words[1] = HIGHPART (low);
178 words[2] = LOWPART (hi);
179 words[3] = HIGHPART (hi);
182 /* Pack an array of 4 words into a two-word integer.
183 WORDS points to the array of words.
184 The integer is stored into *LOW and *HI as two `HOST_WIDE_INT' pieces. */
187 decode (HOST_WIDE_INT *words, unsigned HOST_WIDE_INT *low,
190 *low = words[0] + words[1] * BASE;
191 *hi = words[2] + words[3] * BASE;
194 /* Force the double-word integer L1, H1 to be within the range of the
195 integer type TYPE. Stores the properly truncated and sign-extended
196 double-word integer in *LV, *HV. Returns true if the operation
197 overflows, that is, argument and result are different. */
200 fit_double_type (unsigned HOST_WIDE_INT l1, HOST_WIDE_INT h1,
201 unsigned HOST_WIDE_INT *lv, HOST_WIDE_INT *hv, const_tree type)
203 unsigned HOST_WIDE_INT low0 = l1;
204 HOST_WIDE_INT high0 = h1;
206 int sign_extended_type;
208 if (POINTER_TYPE_P (type)
209 || TREE_CODE (type) == OFFSET_TYPE)
212 prec = TYPE_PRECISION (type);
214 /* Size types *are* sign extended. */
215 sign_extended_type = (!TYPE_UNSIGNED (type)
216 || (TREE_CODE (type) == INTEGER_TYPE
217 && TYPE_IS_SIZETYPE (type)));
219 /* First clear all bits that are beyond the type's precision. */
220 if (prec >= 2 * HOST_BITS_PER_WIDE_INT)
222 else if (prec > HOST_BITS_PER_WIDE_INT)
223 h1 &= ~((HOST_WIDE_INT) (-1) << (prec - HOST_BITS_PER_WIDE_INT));
227 if (prec < HOST_BITS_PER_WIDE_INT)
228 l1 &= ~((HOST_WIDE_INT) (-1) << prec);
231 /* Then do sign extension if necessary. */
232 if (!sign_extended_type)
233 /* No sign extension */;
234 else if (prec >= 2 * HOST_BITS_PER_WIDE_INT)
235 /* Correct width already. */;
236 else if (prec > HOST_BITS_PER_WIDE_INT)
238 /* Sign extend top half? */
239 if (h1 & ((unsigned HOST_WIDE_INT)1
240 << (prec - HOST_BITS_PER_WIDE_INT - 1)))
241 h1 |= (HOST_WIDE_INT) (-1) << (prec - HOST_BITS_PER_WIDE_INT);
243 else if (prec == HOST_BITS_PER_WIDE_INT)
245 if ((HOST_WIDE_INT)l1 < 0)
250 /* Sign extend bottom half? */
251 if (l1 & ((unsigned HOST_WIDE_INT)1 << (prec - 1)))
254 l1 |= (HOST_WIDE_INT)(-1) << prec;
261 /* If the value didn't fit, signal overflow. */
262 return l1 != low0 || h1 != high0;
265 /* We force the double-int HIGH:LOW to the range of the type TYPE by
266 sign or zero extending it.
267 OVERFLOWABLE indicates if we are interested
268 in overflow of the value, when >0 we are only interested in signed
269 overflow, for <0 we are interested in any overflow. OVERFLOWED
270 indicates whether overflow has already occurred. CONST_OVERFLOWED
271 indicates whether constant overflow has already occurred. We force
272 T's value to be within range of T's type (by setting to 0 or 1 all
273 the bits outside the type's range). We set TREE_OVERFLOWED if,
274 OVERFLOWED is nonzero,
275 or OVERFLOWABLE is >0 and signed overflow occurs
276 or OVERFLOWABLE is <0 and any overflow occurs
277 We return a new tree node for the extended double-int. The node
278 is shared if no overflow flags are set. */
281 force_fit_type_double (tree type, unsigned HOST_WIDE_INT low,
282 HOST_WIDE_INT high, int overflowable,
285 int sign_extended_type;
288 /* Size types *are* sign extended. */
289 sign_extended_type = (!TYPE_UNSIGNED (type)
290 || (TREE_CODE (type) == INTEGER_TYPE
291 && TYPE_IS_SIZETYPE (type)));
293 overflow = fit_double_type (low, high, &low, &high, type);
295 /* If we need to set overflow flags, return a new unshared node. */
296 if (overflowed || overflow)
300 || (overflowable > 0 && sign_extended_type))
302 tree t = make_node (INTEGER_CST);
303 TREE_INT_CST_LOW (t) = low;
304 TREE_INT_CST_HIGH (t) = high;
305 TREE_TYPE (t) = type;
306 TREE_OVERFLOW (t) = 1;
311 /* Else build a shared node. */
312 return build_int_cst_wide (type, low, high);
315 /* Add two doubleword integers with doubleword result.
316 Return nonzero if the operation overflows according to UNSIGNED_P.
317 Each argument is given as two `HOST_WIDE_INT' pieces.
318 One argument is L1 and H1; the other, L2 and H2.
319 The value is stored as two `HOST_WIDE_INT' pieces in *LV and *HV. */
322 add_double_with_sign (unsigned HOST_WIDE_INT l1, HOST_WIDE_INT h1,
323 unsigned HOST_WIDE_INT l2, HOST_WIDE_INT h2,
324 unsigned HOST_WIDE_INT *lv, HOST_WIDE_INT *hv,
327 unsigned HOST_WIDE_INT l;
331 h = h1 + h2 + (l < l1);
337 return (unsigned HOST_WIDE_INT) h < (unsigned HOST_WIDE_INT) h1;
339 return OVERFLOW_SUM_SIGN (h1, h2, h);
342 /* Negate a doubleword integer with doubleword result.
343 Return nonzero if the operation overflows, assuming it's signed.
344 The argument is given as two `HOST_WIDE_INT' pieces in L1 and H1.
345 The value is stored as two `HOST_WIDE_INT' pieces in *LV and *HV. */
348 neg_double (unsigned HOST_WIDE_INT l1, HOST_WIDE_INT h1,
349 unsigned HOST_WIDE_INT *lv, HOST_WIDE_INT *hv)
355 return (*hv & h1) < 0;
365 /* Multiply two doubleword integers with doubleword result.
366 Return nonzero if the operation overflows according to UNSIGNED_P.
367 Each argument is given as two `HOST_WIDE_INT' pieces.
368 One argument is L1 and H1; the other, L2 and H2.
369 The value is stored as two `HOST_WIDE_INT' pieces in *LV and *HV. */
372 mul_double_with_sign (unsigned HOST_WIDE_INT l1, HOST_WIDE_INT h1,
373 unsigned HOST_WIDE_INT l2, HOST_WIDE_INT h2,
374 unsigned HOST_WIDE_INT *lv, HOST_WIDE_INT *hv,
377 HOST_WIDE_INT arg1[4];
378 HOST_WIDE_INT arg2[4];
379 HOST_WIDE_INT prod[4 * 2];
380 unsigned HOST_WIDE_INT carry;
382 unsigned HOST_WIDE_INT toplow, neglow;
383 HOST_WIDE_INT tophigh, neghigh;
385 encode (arg1, l1, h1);
386 encode (arg2, l2, h2);
388 memset (prod, 0, sizeof prod);
390 for (i = 0; i < 4; i++)
393 for (j = 0; j < 4; j++)
396 /* This product is <= 0xFFFE0001, the sum <= 0xFFFF0000. */
397 carry += arg1[i] * arg2[j];
398 /* Since prod[p] < 0xFFFF, this sum <= 0xFFFFFFFF. */
400 prod[k] = LOWPART (carry);
401 carry = HIGHPART (carry);
406 decode (prod, lv, hv);
407 decode (prod + 4, &toplow, &tophigh);
409 /* Unsigned overflow is immediate. */
411 return (toplow | tophigh) != 0;
413 /* Check for signed overflow by calculating the signed representation of the
414 top half of the result; it should agree with the low half's sign bit. */
417 neg_double (l2, h2, &neglow, &neghigh);
418 add_double (neglow, neghigh, toplow, tophigh, &toplow, &tophigh);
422 neg_double (l1, h1, &neglow, &neghigh);
423 add_double (neglow, neghigh, toplow, tophigh, &toplow, &tophigh);
425 return (*hv < 0 ? ~(toplow & tophigh) : toplow | tophigh) != 0;
428 /* Shift the doubleword integer in L1, H1 left by COUNT places
429 keeping only PREC bits of result.
430 Shift right if COUNT is negative.
431 ARITH nonzero specifies arithmetic shifting; otherwise use logical shift.
432 Store the value as two `HOST_WIDE_INT' pieces in *LV and *HV. */
435 lshift_double (unsigned HOST_WIDE_INT l1, HOST_WIDE_INT h1,
436 HOST_WIDE_INT count, unsigned int prec,
437 unsigned HOST_WIDE_INT *lv, HOST_WIDE_INT *hv, int arith)
439 unsigned HOST_WIDE_INT signmask;
443 rshift_double (l1, h1, -count, prec, lv, hv, arith);
447 if (SHIFT_COUNT_TRUNCATED)
450 if (count >= 2 * HOST_BITS_PER_WIDE_INT)
452 /* Shifting by the host word size is undefined according to the
453 ANSI standard, so we must handle this as a special case. */
457 else if (count >= HOST_BITS_PER_WIDE_INT)
459 *hv = l1 << (count - HOST_BITS_PER_WIDE_INT);
464 *hv = (((unsigned HOST_WIDE_INT) h1 << count)
465 | (l1 >> (HOST_BITS_PER_WIDE_INT - count - 1) >> 1));
469 /* Sign extend all bits that are beyond the precision. */
471 signmask = -((prec > HOST_BITS_PER_WIDE_INT
472 ? ((unsigned HOST_WIDE_INT) *hv
473 >> (prec - HOST_BITS_PER_WIDE_INT - 1))
474 : (*lv >> (prec - 1))) & 1);
476 if (prec >= 2 * HOST_BITS_PER_WIDE_INT)
478 else if (prec >= HOST_BITS_PER_WIDE_INT)
480 *hv &= ~((HOST_WIDE_INT) (-1) << (prec - HOST_BITS_PER_WIDE_INT));
481 *hv |= signmask << (prec - HOST_BITS_PER_WIDE_INT);
486 *lv &= ~((unsigned HOST_WIDE_INT) (-1) << prec);
487 *lv |= signmask << prec;
491 /* Shift the doubleword integer in L1, H1 right by COUNT places
492 keeping only PREC bits of result. COUNT must be positive.
493 ARITH nonzero specifies arithmetic shifting; otherwise use logical shift.
494 Store the value as two `HOST_WIDE_INT' pieces in *LV and *HV. */
497 rshift_double (unsigned HOST_WIDE_INT l1, HOST_WIDE_INT h1,
498 HOST_WIDE_INT count, unsigned int prec,
499 unsigned HOST_WIDE_INT *lv, HOST_WIDE_INT *hv,
502 unsigned HOST_WIDE_INT signmask;
505 ? -((unsigned HOST_WIDE_INT) h1 >> (HOST_BITS_PER_WIDE_INT - 1))
508 if (SHIFT_COUNT_TRUNCATED)
511 if (count >= 2 * HOST_BITS_PER_WIDE_INT)
513 /* Shifting by the host word size is undefined according to the
514 ANSI standard, so we must handle this as a special case. */
518 else if (count >= HOST_BITS_PER_WIDE_INT)
521 *lv = (unsigned HOST_WIDE_INT) h1 >> (count - HOST_BITS_PER_WIDE_INT);
525 *hv = (unsigned HOST_WIDE_INT) h1 >> count;
527 | ((unsigned HOST_WIDE_INT) h1 << (HOST_BITS_PER_WIDE_INT - count - 1) << 1));
530 /* Zero / sign extend all bits that are beyond the precision. */
532 if (count >= (HOST_WIDE_INT)prec)
537 else if ((prec - count) >= 2 * HOST_BITS_PER_WIDE_INT)
539 else if ((prec - count) >= HOST_BITS_PER_WIDE_INT)
541 *hv &= ~((HOST_WIDE_INT) (-1) << (prec - count - HOST_BITS_PER_WIDE_INT));
542 *hv |= signmask << (prec - count - HOST_BITS_PER_WIDE_INT);
547 *lv &= ~((unsigned HOST_WIDE_INT) (-1) << (prec - count));
548 *lv |= signmask << (prec - count);
552 /* Rotate the doubleword integer in L1, H1 left by COUNT places
553 keeping only PREC bits of result.
554 Rotate right if COUNT is negative.
555 Store the value as two `HOST_WIDE_INT' pieces in *LV and *HV. */
558 lrotate_double (unsigned HOST_WIDE_INT l1, HOST_WIDE_INT h1,
559 HOST_WIDE_INT count, unsigned int prec,
560 unsigned HOST_WIDE_INT *lv, HOST_WIDE_INT *hv)
562 unsigned HOST_WIDE_INT s1l, s2l;
563 HOST_WIDE_INT s1h, s2h;
569 lshift_double (l1, h1, count, prec, &s1l, &s1h, 0);
570 rshift_double (l1, h1, prec - count, prec, &s2l, &s2h, 0);
575 /* Rotate the doubleword integer in L1, H1 left by COUNT places
576 keeping only PREC bits of result. COUNT must be positive.
577 Store the value as two `HOST_WIDE_INT' pieces in *LV and *HV. */
580 rrotate_double (unsigned HOST_WIDE_INT l1, HOST_WIDE_INT h1,
581 HOST_WIDE_INT count, unsigned int prec,
582 unsigned HOST_WIDE_INT *lv, HOST_WIDE_INT *hv)
584 unsigned HOST_WIDE_INT s1l, s2l;
585 HOST_WIDE_INT s1h, s2h;
591 rshift_double (l1, h1, count, prec, &s1l, &s1h, 0);
592 lshift_double (l1, h1, prec - count, prec, &s2l, &s2h, 0);
597 /* Divide doubleword integer LNUM, HNUM by doubleword integer LDEN, HDEN
598 for a quotient (stored in *LQUO, *HQUO) and remainder (in *LREM, *HREM).
599 CODE is a tree code for a kind of division, one of
600 TRUNC_DIV_EXPR, FLOOR_DIV_EXPR, CEIL_DIV_EXPR, ROUND_DIV_EXPR
602 It controls how the quotient is rounded to an integer.
603 Return nonzero if the operation overflows.
604 UNS nonzero says do unsigned division. */
607 div_and_round_double (enum tree_code code, int uns,
608 unsigned HOST_WIDE_INT lnum_orig, /* num == numerator == dividend */
609 HOST_WIDE_INT hnum_orig,
610 unsigned HOST_WIDE_INT lden_orig, /* den == denominator == divisor */
611 HOST_WIDE_INT hden_orig,
612 unsigned HOST_WIDE_INT *lquo,
613 HOST_WIDE_INT *hquo, unsigned HOST_WIDE_INT *lrem,
617 HOST_WIDE_INT num[4 + 1]; /* extra element for scaling. */
618 HOST_WIDE_INT den[4], quo[4];
620 unsigned HOST_WIDE_INT work;
621 unsigned HOST_WIDE_INT carry = 0;
622 unsigned HOST_WIDE_INT lnum = lnum_orig;
623 HOST_WIDE_INT hnum = hnum_orig;
624 unsigned HOST_WIDE_INT lden = lden_orig;
625 HOST_WIDE_INT hden = hden_orig;
628 if (hden == 0 && lden == 0)
629 overflow = 1, lden = 1;
631 /* Calculate quotient sign and convert operands to unsigned. */
637 /* (minimum integer) / (-1) is the only overflow case. */
638 if (neg_double (lnum, hnum, &lnum, &hnum)
639 && ((HOST_WIDE_INT) lden & hden) == -1)
645 neg_double (lden, hden, &lden, &hden);
649 if (hnum == 0 && hden == 0)
650 { /* single precision */
652 /* This unsigned division rounds toward zero. */
658 { /* trivial case: dividend < divisor */
659 /* hden != 0 already checked. */
666 memset (quo, 0, sizeof quo);
668 memset (num, 0, sizeof num); /* to zero 9th element */
669 memset (den, 0, sizeof den);
671 encode (num, lnum, hnum);
672 encode (den, lden, hden);
674 /* Special code for when the divisor < BASE. */
675 if (hden == 0 && lden < (unsigned HOST_WIDE_INT) BASE)
677 /* hnum != 0 already checked. */
678 for (i = 4 - 1; i >= 0; i--)
680 work = num[i] + carry * BASE;
681 quo[i] = work / lden;
687 /* Full double precision division,
688 with thanks to Don Knuth's "Seminumerical Algorithms". */
689 int num_hi_sig, den_hi_sig;
690 unsigned HOST_WIDE_INT quo_est, scale;
692 /* Find the highest nonzero divisor digit. */
693 for (i = 4 - 1;; i--)
700 /* Insure that the first digit of the divisor is at least BASE/2.
701 This is required by the quotient digit estimation algorithm. */
703 scale = BASE / (den[den_hi_sig] + 1);
705 { /* scale divisor and dividend */
707 for (i = 0; i <= 4 - 1; i++)
709 work = (num[i] * scale) + carry;
710 num[i] = LOWPART (work);
711 carry = HIGHPART (work);
716 for (i = 0; i <= 4 - 1; i++)
718 work = (den[i] * scale) + carry;
719 den[i] = LOWPART (work);
720 carry = HIGHPART (work);
721 if (den[i] != 0) den_hi_sig = i;
728 for (i = num_hi_sig - den_hi_sig - 1; i >= 0; i--)
730 /* Guess the next quotient digit, quo_est, by dividing the first
731 two remaining dividend digits by the high order quotient digit.
732 quo_est is never low and is at most 2 high. */
733 unsigned HOST_WIDE_INT tmp;
735 num_hi_sig = i + den_hi_sig + 1;
736 work = num[num_hi_sig] * BASE + num[num_hi_sig - 1];
737 if (num[num_hi_sig] != den[den_hi_sig])
738 quo_est = work / den[den_hi_sig];
742 /* Refine quo_est so it's usually correct, and at most one high. */
743 tmp = work - quo_est * den[den_hi_sig];
745 && (den[den_hi_sig - 1] * quo_est
746 > (tmp * BASE + num[num_hi_sig - 2])))
749 /* Try QUO_EST as the quotient digit, by multiplying the
750 divisor by QUO_EST and subtracting from the remaining dividend.
751 Keep in mind that QUO_EST is the I - 1st digit. */
754 for (j = 0; j <= den_hi_sig; j++)
756 work = quo_est * den[j] + carry;
757 carry = HIGHPART (work);
758 work = num[i + j] - LOWPART (work);
759 num[i + j] = LOWPART (work);
760 carry += HIGHPART (work) != 0;
763 /* If quo_est was high by one, then num[i] went negative and
764 we need to correct things. */
765 if (num[num_hi_sig] < (HOST_WIDE_INT) carry)
768 carry = 0; /* add divisor back in */
769 for (j = 0; j <= den_hi_sig; j++)
771 work = num[i + j] + den[j] + carry;
772 carry = HIGHPART (work);
773 num[i + j] = LOWPART (work);
776 num [num_hi_sig] += carry;
779 /* Store the quotient digit. */
784 decode (quo, lquo, hquo);
787 /* If result is negative, make it so. */
789 neg_double (*lquo, *hquo, lquo, hquo);
791 /* Compute trial remainder: rem = num - (quo * den) */
792 mul_double (*lquo, *hquo, lden_orig, hden_orig, lrem, hrem);
793 neg_double (*lrem, *hrem, lrem, hrem);
794 add_double (lnum_orig, hnum_orig, *lrem, *hrem, lrem, hrem);
799 case TRUNC_MOD_EXPR: /* round toward zero */
800 case EXACT_DIV_EXPR: /* for this one, it shouldn't matter */
804 case FLOOR_MOD_EXPR: /* round toward negative infinity */
805 if (quo_neg && (*lrem != 0 || *hrem != 0)) /* ratio < 0 && rem != 0 */
808 add_double (*lquo, *hquo, (HOST_WIDE_INT) -1, (HOST_WIDE_INT) -1,
816 case CEIL_MOD_EXPR: /* round toward positive infinity */
817 if (!quo_neg && (*lrem != 0 || *hrem != 0)) /* ratio > 0 && rem != 0 */
819 add_double (*lquo, *hquo, (HOST_WIDE_INT) 1, (HOST_WIDE_INT) 0,
827 case ROUND_MOD_EXPR: /* round to closest integer */
829 unsigned HOST_WIDE_INT labs_rem = *lrem;
830 HOST_WIDE_INT habs_rem = *hrem;
831 unsigned HOST_WIDE_INT labs_den = lden, ltwice;
832 HOST_WIDE_INT habs_den = hden, htwice;
834 /* Get absolute values. */
836 neg_double (*lrem, *hrem, &labs_rem, &habs_rem);
838 neg_double (lden, hden, &labs_den, &habs_den);
840 /* If (2 * abs (lrem) >= abs (lden)), adjust the quotient. */
841 mul_double ((HOST_WIDE_INT) 2, (HOST_WIDE_INT) 0,
842 labs_rem, habs_rem, <wice, &htwice);
844 if (((unsigned HOST_WIDE_INT) habs_den
845 < (unsigned HOST_WIDE_INT) htwice)
846 || (((unsigned HOST_WIDE_INT) habs_den
847 == (unsigned HOST_WIDE_INT) htwice)
848 && (labs_den <= ltwice)))
852 add_double (*lquo, *hquo,
853 (HOST_WIDE_INT) -1, (HOST_WIDE_INT) -1, lquo, hquo);
856 add_double (*lquo, *hquo, (HOST_WIDE_INT) 1, (HOST_WIDE_INT) 0,
868 /* Compute true remainder: rem = num - (quo * den) */
869 mul_double (*lquo, *hquo, lden_orig, hden_orig, lrem, hrem);
870 neg_double (*lrem, *hrem, lrem, hrem);
871 add_double (lnum_orig, hnum_orig, *lrem, *hrem, lrem, hrem);
875 /* If ARG2 divides ARG1 with zero remainder, carries out the division
876 of type CODE and returns the quotient.
877 Otherwise returns NULL_TREE. */
880 div_if_zero_remainder (enum tree_code code, const_tree arg1, const_tree arg2)
882 unsigned HOST_WIDE_INT int1l, int2l;
883 HOST_WIDE_INT int1h, int2h;
884 unsigned HOST_WIDE_INT quol, reml;
885 HOST_WIDE_INT quoh, remh;
886 tree type = TREE_TYPE (arg1);
887 int uns = TYPE_UNSIGNED (type);
889 int1l = TREE_INT_CST_LOW (arg1);
890 int1h = TREE_INT_CST_HIGH (arg1);
891 /* &obj[0] + -128 really should be compiled as &obj[-8] rather than
892 &obj[some_exotic_number]. */
893 if (POINTER_TYPE_P (type))
896 type = signed_type_for (type);
897 fit_double_type (int1l, int1h, &int1l, &int1h,
901 fit_double_type (int1l, int1h, &int1l, &int1h, type);
902 int2l = TREE_INT_CST_LOW (arg2);
903 int2h = TREE_INT_CST_HIGH (arg2);
905 div_and_round_double (code, uns, int1l, int1h, int2l, int2h,
906 &quol, &quoh, &reml, &remh);
907 if (remh != 0 || reml != 0)
910 return build_int_cst_wide (type, quol, quoh);
913 /* This is nonzero if we should defer warnings about undefined
914 overflow. This facility exists because these warnings are a
915 special case. The code to estimate loop iterations does not want
916 to issue any warnings, since it works with expressions which do not
917 occur in user code. Various bits of cleanup code call fold(), but
918 only use the result if it has certain characteristics (e.g., is a
919 constant); that code only wants to issue a warning if the result is
922 static int fold_deferring_overflow_warnings;
924 /* If a warning about undefined overflow is deferred, this is the
925 warning. Note that this may cause us to turn two warnings into
926 one, but that is fine since it is sufficient to only give one
927 warning per expression. */
929 static const char* fold_deferred_overflow_warning;
931 /* If a warning about undefined overflow is deferred, this is the
932 level at which the warning should be emitted. */
934 static enum warn_strict_overflow_code fold_deferred_overflow_code;
936 /* Start deferring overflow warnings. We could use a stack here to
937 permit nested calls, but at present it is not necessary. */
940 fold_defer_overflow_warnings (void)
942 ++fold_deferring_overflow_warnings;
945 /* Stop deferring overflow warnings. If there is a pending warning,
946 and ISSUE is true, then issue the warning if appropriate. STMT is
947 the statement with which the warning should be associated (used for
948 location information); STMT may be NULL. CODE is the level of the
949 warning--a warn_strict_overflow_code value. This function will use
950 the smaller of CODE and the deferred code when deciding whether to
951 issue the warning. CODE may be zero to mean to always use the
955 fold_undefer_overflow_warnings (bool issue, const_gimple stmt, int code)
960 gcc_assert (fold_deferring_overflow_warnings > 0);
961 --fold_deferring_overflow_warnings;
962 if (fold_deferring_overflow_warnings > 0)
964 if (fold_deferred_overflow_warning != NULL
966 && code < (int) fold_deferred_overflow_code)
967 fold_deferred_overflow_code = code;
971 warnmsg = fold_deferred_overflow_warning;
972 fold_deferred_overflow_warning = NULL;
974 if (!issue || warnmsg == NULL)
977 if (gimple_no_warning_p (stmt))
980 /* Use the smallest code level when deciding to issue the
982 if (code == 0 || code > (int) fold_deferred_overflow_code)
983 code = fold_deferred_overflow_code;
985 if (!issue_strict_overflow_warning (code))
989 locus = input_location;
991 locus = gimple_location (stmt);
992 warning (OPT_Wstrict_overflow, "%H%s", &locus, warnmsg);
995 /* Stop deferring overflow warnings, ignoring any deferred
999 fold_undefer_and_ignore_overflow_warnings (void)
1001 fold_undefer_overflow_warnings (false, NULL, 0);
1004 /* Whether we are deferring overflow warnings. */
1007 fold_deferring_overflow_warnings_p (void)
1009 return fold_deferring_overflow_warnings > 0;
1012 /* This is called when we fold something based on the fact that signed
1013 overflow is undefined. */
1016 fold_overflow_warning (const char* gmsgid, enum warn_strict_overflow_code wc)
1018 if (fold_deferring_overflow_warnings > 0)
1020 if (fold_deferred_overflow_warning == NULL
1021 || wc < fold_deferred_overflow_code)
1023 fold_deferred_overflow_warning = gmsgid;
1024 fold_deferred_overflow_code = wc;
1027 else if (issue_strict_overflow_warning (wc))
1028 warning (OPT_Wstrict_overflow, gmsgid);
1031 /* Return true if the built-in mathematical function specified by CODE
1032 is odd, i.e. -f(x) == f(-x). */
1035 negate_mathfn_p (enum built_in_function code)
1039 CASE_FLT_FN (BUILT_IN_ASIN):
1040 CASE_FLT_FN (BUILT_IN_ASINH):
1041 CASE_FLT_FN (BUILT_IN_ATAN):
1042 CASE_FLT_FN (BUILT_IN_ATANH):
1043 CASE_FLT_FN (BUILT_IN_CASIN):
1044 CASE_FLT_FN (BUILT_IN_CASINH):
1045 CASE_FLT_FN (BUILT_IN_CATAN):
1046 CASE_FLT_FN (BUILT_IN_CATANH):
1047 CASE_FLT_FN (BUILT_IN_CBRT):
1048 CASE_FLT_FN (BUILT_IN_CPROJ):
1049 CASE_FLT_FN (BUILT_IN_CSIN):
1050 CASE_FLT_FN (BUILT_IN_CSINH):
1051 CASE_FLT_FN (BUILT_IN_CTAN):
1052 CASE_FLT_FN (BUILT_IN_CTANH):
1053 CASE_FLT_FN (BUILT_IN_ERF):
1054 CASE_FLT_FN (BUILT_IN_LLROUND):
1055 CASE_FLT_FN (BUILT_IN_LROUND):
1056 CASE_FLT_FN (BUILT_IN_ROUND):
1057 CASE_FLT_FN (BUILT_IN_SIN):
1058 CASE_FLT_FN (BUILT_IN_SINH):
1059 CASE_FLT_FN (BUILT_IN_TAN):
1060 CASE_FLT_FN (BUILT_IN_TANH):
1061 CASE_FLT_FN (BUILT_IN_TRUNC):
1064 CASE_FLT_FN (BUILT_IN_LLRINT):
1065 CASE_FLT_FN (BUILT_IN_LRINT):
1066 CASE_FLT_FN (BUILT_IN_NEARBYINT):
1067 CASE_FLT_FN (BUILT_IN_RINT):
1068 return !flag_rounding_math;
1076 /* Check whether we may negate an integer constant T without causing
1080 may_negate_without_overflow_p (const_tree t)
1082 unsigned HOST_WIDE_INT val;
1086 gcc_assert (TREE_CODE (t) == INTEGER_CST);
1088 type = TREE_TYPE (t);
1089 if (TYPE_UNSIGNED (type))
1092 prec = TYPE_PRECISION (type);
1093 if (prec > HOST_BITS_PER_WIDE_INT)
1095 if (TREE_INT_CST_LOW (t) != 0)
1097 prec -= HOST_BITS_PER_WIDE_INT;
1098 val = TREE_INT_CST_HIGH (t);
1101 val = TREE_INT_CST_LOW (t);
1102 if (prec < HOST_BITS_PER_WIDE_INT)
1103 val &= ((unsigned HOST_WIDE_INT) 1 << prec) - 1;
1104 return val != ((unsigned HOST_WIDE_INT) 1 << (prec - 1));
1107 /* Determine whether an expression T can be cheaply negated using
1108 the function negate_expr without introducing undefined overflow. */
1111 negate_expr_p (tree t)
1118 type = TREE_TYPE (t);
1120 STRIP_SIGN_NOPS (t);
1121 switch (TREE_CODE (t))
1124 if (TYPE_OVERFLOW_WRAPS (type))
1127 /* Check that -CST will not overflow type. */
1128 return may_negate_without_overflow_p (t);
1130 return (INTEGRAL_TYPE_P (type)
1131 && TYPE_OVERFLOW_WRAPS (type));
1139 return negate_expr_p (TREE_REALPART (t))
1140 && negate_expr_p (TREE_IMAGPART (t));
1143 return negate_expr_p (TREE_OPERAND (t, 0))
1144 && negate_expr_p (TREE_OPERAND (t, 1));
1147 return negate_expr_p (TREE_OPERAND (t, 0));
1150 if (HONOR_SIGN_DEPENDENT_ROUNDING (TYPE_MODE (type))
1151 || HONOR_SIGNED_ZEROS (TYPE_MODE (type)))
1153 /* -(A + B) -> (-B) - A. */
1154 if (negate_expr_p (TREE_OPERAND (t, 1))
1155 && reorder_operands_p (TREE_OPERAND (t, 0),
1156 TREE_OPERAND (t, 1)))
1158 /* -(A + B) -> (-A) - B. */
1159 return negate_expr_p (TREE_OPERAND (t, 0));
1162 /* We can't turn -(A-B) into B-A when we honor signed zeros. */
1163 return !HONOR_SIGN_DEPENDENT_ROUNDING (TYPE_MODE (type))
1164 && !HONOR_SIGNED_ZEROS (TYPE_MODE (type))
1165 && reorder_operands_p (TREE_OPERAND (t, 0),
1166 TREE_OPERAND (t, 1));
1169 if (TYPE_UNSIGNED (TREE_TYPE (t)))
1175 if (! HONOR_SIGN_DEPENDENT_ROUNDING (TYPE_MODE (TREE_TYPE (t))))
1176 return negate_expr_p (TREE_OPERAND (t, 1))
1177 || negate_expr_p (TREE_OPERAND (t, 0));
1180 case TRUNC_DIV_EXPR:
1181 case ROUND_DIV_EXPR:
1182 case FLOOR_DIV_EXPR:
1184 case EXACT_DIV_EXPR:
1185 /* In general we can't negate A / B, because if A is INT_MIN and
1186 B is 1, we may turn this into INT_MIN / -1 which is undefined
1187 and actually traps on some architectures. But if overflow is
1188 undefined, we can negate, because - (INT_MIN / 1) is an
1190 if (INTEGRAL_TYPE_P (TREE_TYPE (t))
1191 && !TYPE_OVERFLOW_UNDEFINED (TREE_TYPE (t)))
1193 return negate_expr_p (TREE_OPERAND (t, 1))
1194 || negate_expr_p (TREE_OPERAND (t, 0));
1197 /* Negate -((double)float) as (double)(-float). */
1198 if (TREE_CODE (type) == REAL_TYPE)
1200 tree tem = strip_float_extensions (t);
1202 return negate_expr_p (tem);
1207 /* Negate -f(x) as f(-x). */
1208 if (negate_mathfn_p (builtin_mathfn_code (t)))
1209 return negate_expr_p (CALL_EXPR_ARG (t, 0));
1213 /* Optimize -((int)x >> 31) into (unsigned)x >> 31. */
1214 if (TREE_CODE (TREE_OPERAND (t, 1)) == INTEGER_CST)
1216 tree op1 = TREE_OPERAND (t, 1);
1217 if (TREE_INT_CST_HIGH (op1) == 0
1218 && (unsigned HOST_WIDE_INT) (TYPE_PRECISION (type) - 1)
1219 == TREE_INT_CST_LOW (op1))
1230 /* Given T, an expression, return a folded tree for -T or NULL_TREE, if no
1231 simplification is possible.
1232 If negate_expr_p would return true for T, NULL_TREE will never be
1236 fold_negate_expr (tree t)
1238 tree type = TREE_TYPE (t);
1241 switch (TREE_CODE (t))
1243 /* Convert - (~A) to A + 1. */
1245 if (INTEGRAL_TYPE_P (type))
1246 return fold_build2 (PLUS_EXPR, type, TREE_OPERAND (t, 0),
1247 build_int_cst (type, 1));
1251 tem = fold_negate_const (t, type);
1252 if (TREE_OVERFLOW (tem) == TREE_OVERFLOW (t)
1253 || !TYPE_OVERFLOW_TRAPS (type))
1258 tem = fold_negate_const (t, type);
1259 /* Two's complement FP formats, such as c4x, may overflow. */
1260 if (!TREE_OVERFLOW (tem) || !flag_trapping_math)
1265 tem = fold_negate_const (t, type);
1270 tree rpart = negate_expr (TREE_REALPART (t));
1271 tree ipart = negate_expr (TREE_IMAGPART (t));
1273 if ((TREE_CODE (rpart) == REAL_CST
1274 && TREE_CODE (ipart) == REAL_CST)
1275 || (TREE_CODE (rpart) == INTEGER_CST
1276 && TREE_CODE (ipart) == INTEGER_CST))
1277 return build_complex (type, rpart, ipart);
1282 if (negate_expr_p (t))
1283 return fold_build2 (COMPLEX_EXPR, type,
1284 fold_negate_expr (TREE_OPERAND (t, 0)),
1285 fold_negate_expr (TREE_OPERAND (t, 1)));
1289 if (negate_expr_p (t))
1290 return fold_build1 (CONJ_EXPR, type,
1291 fold_negate_expr (TREE_OPERAND (t, 0)));
1295 return TREE_OPERAND (t, 0);
1298 if (!HONOR_SIGN_DEPENDENT_ROUNDING (TYPE_MODE (type))
1299 && !HONOR_SIGNED_ZEROS (TYPE_MODE (type)))
1301 /* -(A + B) -> (-B) - A. */
1302 if (negate_expr_p (TREE_OPERAND (t, 1))
1303 && reorder_operands_p (TREE_OPERAND (t, 0),
1304 TREE_OPERAND (t, 1)))
1306 tem = negate_expr (TREE_OPERAND (t, 1));
1307 return fold_build2 (MINUS_EXPR, type,
1308 tem, TREE_OPERAND (t, 0));
1311 /* -(A + B) -> (-A) - B. */
1312 if (negate_expr_p (TREE_OPERAND (t, 0)))
1314 tem = negate_expr (TREE_OPERAND (t, 0));
1315 return fold_build2 (MINUS_EXPR, type,
1316 tem, TREE_OPERAND (t, 1));
1322 /* - (A - B) -> B - A */
1323 if (!HONOR_SIGN_DEPENDENT_ROUNDING (TYPE_MODE (type))
1324 && !HONOR_SIGNED_ZEROS (TYPE_MODE (type))
1325 && reorder_operands_p (TREE_OPERAND (t, 0), TREE_OPERAND (t, 1)))
1326 return fold_build2 (MINUS_EXPR, type,
1327 TREE_OPERAND (t, 1), TREE_OPERAND (t, 0));
1331 if (TYPE_UNSIGNED (type))
1337 if (! HONOR_SIGN_DEPENDENT_ROUNDING (TYPE_MODE (type)))
1339 tem = TREE_OPERAND (t, 1);
1340 if (negate_expr_p (tem))
1341 return fold_build2 (TREE_CODE (t), type,
1342 TREE_OPERAND (t, 0), negate_expr (tem));
1343 tem = TREE_OPERAND (t, 0);
1344 if (negate_expr_p (tem))
1345 return fold_build2 (TREE_CODE (t), type,
1346 negate_expr (tem), TREE_OPERAND (t, 1));
1350 case TRUNC_DIV_EXPR:
1351 case ROUND_DIV_EXPR:
1352 case FLOOR_DIV_EXPR:
1354 case EXACT_DIV_EXPR:
1355 /* In general we can't negate A / B, because if A is INT_MIN and
1356 B is 1, we may turn this into INT_MIN / -1 which is undefined
1357 and actually traps on some architectures. But if overflow is
1358 undefined, we can negate, because - (INT_MIN / 1) is an
1360 if (!INTEGRAL_TYPE_P (type) || TYPE_OVERFLOW_UNDEFINED (type))
1362 const char * const warnmsg = G_("assuming signed overflow does not "
1363 "occur when negating a division");
1364 tem = TREE_OPERAND (t, 1);
1365 if (negate_expr_p (tem))
1367 if (INTEGRAL_TYPE_P (type)
1368 && (TREE_CODE (tem) != INTEGER_CST
1369 || integer_onep (tem)))
1370 fold_overflow_warning (warnmsg, WARN_STRICT_OVERFLOW_MISC);
1371 return fold_build2 (TREE_CODE (t), type,
1372 TREE_OPERAND (t, 0), negate_expr (tem));
1374 tem = TREE_OPERAND (t, 0);
1375 if (negate_expr_p (tem))
1377 if (INTEGRAL_TYPE_P (type)
1378 && (TREE_CODE (tem) != INTEGER_CST
1379 || tree_int_cst_equal (tem, TYPE_MIN_VALUE (type))))
1380 fold_overflow_warning (warnmsg, WARN_STRICT_OVERFLOW_MISC);
1381 return fold_build2 (TREE_CODE (t), type,
1382 negate_expr (tem), TREE_OPERAND (t, 1));
1388 /* Convert -((double)float) into (double)(-float). */
1389 if (TREE_CODE (type) == REAL_TYPE)
1391 tem = strip_float_extensions (t);
1392 if (tem != t && negate_expr_p (tem))
1393 return fold_convert (type, negate_expr (tem));
1398 /* Negate -f(x) as f(-x). */
1399 if (negate_mathfn_p (builtin_mathfn_code (t))
1400 && negate_expr_p (CALL_EXPR_ARG (t, 0)))
1404 fndecl = get_callee_fndecl (t);
1405 arg = negate_expr (CALL_EXPR_ARG (t, 0));
1406 return build_call_expr (fndecl, 1, arg);
1411 /* Optimize -((int)x >> 31) into (unsigned)x >> 31. */
1412 if (TREE_CODE (TREE_OPERAND (t, 1)) == INTEGER_CST)
1414 tree op1 = TREE_OPERAND (t, 1);
1415 if (TREE_INT_CST_HIGH (op1) == 0
1416 && (unsigned HOST_WIDE_INT) (TYPE_PRECISION (type) - 1)
1417 == TREE_INT_CST_LOW (op1))
1419 tree ntype = TYPE_UNSIGNED (type)
1420 ? signed_type_for (type)
1421 : unsigned_type_for (type);
1422 tree temp = fold_convert (ntype, TREE_OPERAND (t, 0));
1423 temp = fold_build2 (RSHIFT_EXPR, ntype, temp, op1);
1424 return fold_convert (type, temp);
1436 /* Like fold_negate_expr, but return a NEGATE_EXPR tree, if T can not be
1437 negated in a simpler way. Also allow for T to be NULL_TREE, in which case
1438 return NULL_TREE. */
1441 negate_expr (tree t)
1448 type = TREE_TYPE (t);
1449 STRIP_SIGN_NOPS (t);
1451 tem = fold_negate_expr (t);
1453 tem = build1 (NEGATE_EXPR, TREE_TYPE (t), t);
1454 return fold_convert (type, tem);
1457 /* Split a tree IN into a constant, literal and variable parts that could be
1458 combined with CODE to make IN. "constant" means an expression with
1459 TREE_CONSTANT but that isn't an actual constant. CODE must be a
1460 commutative arithmetic operation. Store the constant part into *CONP,
1461 the literal in *LITP and return the variable part. If a part isn't
1462 present, set it to null. If the tree does not decompose in this way,
1463 return the entire tree as the variable part and the other parts as null.
1465 If CODE is PLUS_EXPR we also split trees that use MINUS_EXPR. In that
1466 case, we negate an operand that was subtracted. Except if it is a
1467 literal for which we use *MINUS_LITP instead.
1469 If NEGATE_P is true, we are negating all of IN, again except a literal
1470 for which we use *MINUS_LITP instead.
1472 If IN is itself a literal or constant, return it as appropriate.
1474 Note that we do not guarantee that any of the three values will be the
1475 same type as IN, but they will have the same signedness and mode. */
1478 split_tree (tree in, enum tree_code code, tree *conp, tree *litp,
1479 tree *minus_litp, int negate_p)
1487 /* Strip any conversions that don't change the machine mode or signedness. */
1488 STRIP_SIGN_NOPS (in);
1490 if (TREE_CODE (in) == INTEGER_CST || TREE_CODE (in) == REAL_CST
1491 || TREE_CODE (in) == FIXED_CST)
1493 else if (TREE_CODE (in) == code
1494 || ((! FLOAT_TYPE_P (TREE_TYPE (in)) || flag_associative_math)
1495 && ! SAT_FIXED_POINT_TYPE_P (TREE_TYPE (in))
1496 /* We can associate addition and subtraction together (even
1497 though the C standard doesn't say so) for integers because
1498 the value is not affected. For reals, the value might be
1499 affected, so we can't. */
1500 && ((code == PLUS_EXPR && TREE_CODE (in) == MINUS_EXPR)
1501 || (code == MINUS_EXPR && TREE_CODE (in) == PLUS_EXPR))))
1503 tree op0 = TREE_OPERAND (in, 0);
1504 tree op1 = TREE_OPERAND (in, 1);
1505 int neg1_p = TREE_CODE (in) == MINUS_EXPR;
1506 int neg_litp_p = 0, neg_conp_p = 0, neg_var_p = 0;
1508 /* First see if either of the operands is a literal, then a constant. */
1509 if (TREE_CODE (op0) == INTEGER_CST || TREE_CODE (op0) == REAL_CST
1510 || TREE_CODE (op0) == FIXED_CST)
1511 *litp = op0, op0 = 0;
1512 else if (TREE_CODE (op1) == INTEGER_CST || TREE_CODE (op1) == REAL_CST
1513 || TREE_CODE (op1) == FIXED_CST)
1514 *litp = op1, neg_litp_p = neg1_p, op1 = 0;
1516 if (op0 != 0 && TREE_CONSTANT (op0))
1517 *conp = op0, op0 = 0;
1518 else if (op1 != 0 && TREE_CONSTANT (op1))
1519 *conp = op1, neg_conp_p = neg1_p, op1 = 0;
1521 /* If we haven't dealt with either operand, this is not a case we can
1522 decompose. Otherwise, VAR is either of the ones remaining, if any. */
1523 if (op0 != 0 && op1 != 0)
1528 var = op1, neg_var_p = neg1_p;
1530 /* Now do any needed negations. */
1532 *minus_litp = *litp, *litp = 0;
1534 *conp = negate_expr (*conp);
1536 var = negate_expr (var);
1538 else if (TREE_CONSTANT (in))
1546 *minus_litp = *litp, *litp = 0;
1547 else if (*minus_litp)
1548 *litp = *minus_litp, *minus_litp = 0;
1549 *conp = negate_expr (*conp);
1550 var = negate_expr (var);
1556 /* Re-associate trees split by the above function. T1 and T2 are either
1557 expressions to associate or null. Return the new expression, if any. If
1558 we build an operation, do it in TYPE and with CODE. */
1561 associate_trees (tree t1, tree t2, enum tree_code code, tree type)
1568 /* If either input is CODE, a PLUS_EXPR, or a MINUS_EXPR, don't
1569 try to fold this since we will have infinite recursion. But do
1570 deal with any NEGATE_EXPRs. */
1571 if (TREE_CODE (t1) == code || TREE_CODE (t2) == code
1572 || TREE_CODE (t1) == MINUS_EXPR || TREE_CODE (t2) == MINUS_EXPR)
1574 if (code == PLUS_EXPR)
1576 if (TREE_CODE (t1) == NEGATE_EXPR)
1577 return build2 (MINUS_EXPR, type, fold_convert (type, t2),
1578 fold_convert (type, TREE_OPERAND (t1, 0)));
1579 else if (TREE_CODE (t2) == NEGATE_EXPR)
1580 return build2 (MINUS_EXPR, type, fold_convert (type, t1),
1581 fold_convert (type, TREE_OPERAND (t2, 0)));
1582 else if (integer_zerop (t2))
1583 return fold_convert (type, t1);
1585 else if (code == MINUS_EXPR)
1587 if (integer_zerop (t2))
1588 return fold_convert (type, t1);
1591 return build2 (code, type, fold_convert (type, t1),
1592 fold_convert (type, t2));
1595 return fold_build2 (code, type, fold_convert (type, t1),
1596 fold_convert (type, t2));
1599 /* Check whether TYPE1 and TYPE2 are equivalent integer types, suitable
1600 for use in int_const_binop, size_binop and size_diffop. */
1603 int_binop_types_match_p (enum tree_code code, const_tree type1, const_tree type2)
1605 if (TREE_CODE (type1) != INTEGER_TYPE && !POINTER_TYPE_P (type1))
1607 if (TREE_CODE (type2) != INTEGER_TYPE && !POINTER_TYPE_P (type2))
1622 return TYPE_UNSIGNED (type1) == TYPE_UNSIGNED (type2)
1623 && TYPE_PRECISION (type1) == TYPE_PRECISION (type2)
1624 && TYPE_MODE (type1) == TYPE_MODE (type2);
1628 /* Combine two integer constants ARG1 and ARG2 under operation CODE
1629 to produce a new constant. Return NULL_TREE if we don't know how
1630 to evaluate CODE at compile-time.
1632 If NOTRUNC is nonzero, do not truncate the result to fit the data type. */
1635 int_const_binop (enum tree_code code, const_tree arg1, const_tree arg2, int notrunc)
1637 unsigned HOST_WIDE_INT int1l, int2l;
1638 HOST_WIDE_INT int1h, int2h;
1639 unsigned HOST_WIDE_INT low;
1641 unsigned HOST_WIDE_INT garbagel;
1642 HOST_WIDE_INT garbageh;
1644 tree type = TREE_TYPE (arg1);
1645 int uns = TYPE_UNSIGNED (type);
1647 = (TREE_CODE (type) == INTEGER_TYPE && TYPE_IS_SIZETYPE (type));
1650 int1l = TREE_INT_CST_LOW (arg1);
1651 int1h = TREE_INT_CST_HIGH (arg1);
1652 int2l = TREE_INT_CST_LOW (arg2);
1653 int2h = TREE_INT_CST_HIGH (arg2);
1658 low = int1l | int2l, hi = int1h | int2h;
1662 low = int1l ^ int2l, hi = int1h ^ int2h;
1666 low = int1l & int2l, hi = int1h & int2h;
1672 /* It's unclear from the C standard whether shifts can overflow.
1673 The following code ignores overflow; perhaps a C standard
1674 interpretation ruling is needed. */
1675 lshift_double (int1l, int1h, int2l, TYPE_PRECISION (type),
1682 lrotate_double (int1l, int1h, int2l, TYPE_PRECISION (type),
1687 overflow = add_double (int1l, int1h, int2l, int2h, &low, &hi);
1691 neg_double (int2l, int2h, &low, &hi);
1692 add_double (int1l, int1h, low, hi, &low, &hi);
1693 overflow = OVERFLOW_SUM_SIGN (hi, int2h, int1h);
1697 overflow = mul_double (int1l, int1h, int2l, int2h, &low, &hi);
1700 case TRUNC_DIV_EXPR:
1701 case FLOOR_DIV_EXPR: case CEIL_DIV_EXPR:
1702 case EXACT_DIV_EXPR:
1703 /* This is a shortcut for a common special case. */
1704 if (int2h == 0 && (HOST_WIDE_INT) int2l > 0
1705 && !TREE_OVERFLOW (arg1)
1706 && !TREE_OVERFLOW (arg2)
1707 && int1h == 0 && (HOST_WIDE_INT) int1l >= 0)
1709 if (code == CEIL_DIV_EXPR)
1712 low = int1l / int2l, hi = 0;
1716 /* ... fall through ... */
1718 case ROUND_DIV_EXPR:
1719 if (int2h == 0 && int2l == 0)
1721 if (int2h == 0 && int2l == 1)
1723 low = int1l, hi = int1h;
1726 if (int1l == int2l && int1h == int2h
1727 && ! (int1l == 0 && int1h == 0))
1732 overflow = div_and_round_double (code, uns, int1l, int1h, int2l, int2h,
1733 &low, &hi, &garbagel, &garbageh);
1736 case TRUNC_MOD_EXPR:
1737 case FLOOR_MOD_EXPR: case CEIL_MOD_EXPR:
1738 /* This is a shortcut for a common special case. */
1739 if (int2h == 0 && (HOST_WIDE_INT) int2l > 0
1740 && !TREE_OVERFLOW (arg1)
1741 && !TREE_OVERFLOW (arg2)
1742 && int1h == 0 && (HOST_WIDE_INT) int1l >= 0)
1744 if (code == CEIL_MOD_EXPR)
1746 low = int1l % int2l, hi = 0;
1750 /* ... fall through ... */
1752 case ROUND_MOD_EXPR:
1753 if (int2h == 0 && int2l == 0)
1755 overflow = div_and_round_double (code, uns,
1756 int1l, int1h, int2l, int2h,
1757 &garbagel, &garbageh, &low, &hi);
1763 low = (((unsigned HOST_WIDE_INT) int1h
1764 < (unsigned HOST_WIDE_INT) int2h)
1765 || (((unsigned HOST_WIDE_INT) int1h
1766 == (unsigned HOST_WIDE_INT) int2h)
1769 low = (int1h < int2h
1770 || (int1h == int2h && int1l < int2l));
1772 if (low == (code == MIN_EXPR))
1773 low = int1l, hi = int1h;
1775 low = int2l, hi = int2h;
1784 t = build_int_cst_wide (TREE_TYPE (arg1), low, hi);
1786 /* Propagate overflow flags ourselves. */
1787 if (((!uns || is_sizetype) && overflow)
1788 | TREE_OVERFLOW (arg1) | TREE_OVERFLOW (arg2))
1791 TREE_OVERFLOW (t) = 1;
1795 t = force_fit_type_double (TREE_TYPE (arg1), low, hi, 1,
1796 ((!uns || is_sizetype) && overflow)
1797 | TREE_OVERFLOW (arg1) | TREE_OVERFLOW (arg2));
1802 /* Combine two constants ARG1 and ARG2 under operation CODE to produce a new
1803 constant. We assume ARG1 and ARG2 have the same data type, or at least
1804 are the same kind of constant and the same machine mode. Return zero if
1805 combining the constants is not allowed in the current operating mode.
1807 If NOTRUNC is nonzero, do not truncate the result to fit the data type. */
1810 const_binop (enum tree_code code, tree arg1, tree arg2, int notrunc)
1812 /* Sanity check for the recursive cases. */
1819 if (TREE_CODE (arg1) == INTEGER_CST)
1820 return int_const_binop (code, arg1, arg2, notrunc);
1822 if (TREE_CODE (arg1) == REAL_CST)
1824 enum machine_mode mode;
1827 REAL_VALUE_TYPE value;
1828 REAL_VALUE_TYPE result;
1832 /* The following codes are handled by real_arithmetic. */
1847 d1 = TREE_REAL_CST (arg1);
1848 d2 = TREE_REAL_CST (arg2);
1850 type = TREE_TYPE (arg1);
1851 mode = TYPE_MODE (type);
1853 /* Don't perform operation if we honor signaling NaNs and
1854 either operand is a NaN. */
1855 if (HONOR_SNANS (mode)
1856 && (REAL_VALUE_ISNAN (d1) || REAL_VALUE_ISNAN (d2)))
1859 /* Don't perform operation if it would raise a division
1860 by zero exception. */
1861 if (code == RDIV_EXPR
1862 && REAL_VALUES_EQUAL (d2, dconst0)
1863 && (flag_trapping_math || ! MODE_HAS_INFINITIES (mode)))
1866 /* If either operand is a NaN, just return it. Otherwise, set up
1867 for floating-point trap; we return an overflow. */
1868 if (REAL_VALUE_ISNAN (d1))
1870 else if (REAL_VALUE_ISNAN (d2))
1873 inexact = real_arithmetic (&value, code, &d1, &d2);
1874 real_convert (&result, mode, &value);
1876 /* Don't constant fold this floating point operation if
1877 the result has overflowed and flag_trapping_math. */
1878 if (flag_trapping_math
1879 && MODE_HAS_INFINITIES (mode)
1880 && REAL_VALUE_ISINF (result)
1881 && !REAL_VALUE_ISINF (d1)
1882 && !REAL_VALUE_ISINF (d2))
1885 /* Don't constant fold this floating point operation if the
1886 result may dependent upon the run-time rounding mode and
1887 flag_rounding_math is set, or if GCC's software emulation
1888 is unable to accurately represent the result. */
1889 if ((flag_rounding_math
1890 || (MODE_COMPOSITE_P (mode) && !flag_unsafe_math_optimizations))
1891 && (inexact || !real_identical (&result, &value)))
1894 t = build_real (type, result);
1896 TREE_OVERFLOW (t) = TREE_OVERFLOW (arg1) | TREE_OVERFLOW (arg2);
1900 if (TREE_CODE (arg1) == FIXED_CST)
1902 FIXED_VALUE_TYPE f1;
1903 FIXED_VALUE_TYPE f2;
1904 FIXED_VALUE_TYPE result;
1909 /* The following codes are handled by fixed_arithmetic. */
1915 case TRUNC_DIV_EXPR:
1916 f2 = TREE_FIXED_CST (arg2);
1921 f2.data.high = TREE_INT_CST_HIGH (arg2);
1922 f2.data.low = TREE_INT_CST_LOW (arg2);
1930 f1 = TREE_FIXED_CST (arg1);
1931 type = TREE_TYPE (arg1);
1932 sat_p = TYPE_SATURATING (type);
1933 overflow_p = fixed_arithmetic (&result, code, &f1, &f2, sat_p);
1934 t = build_fixed (type, result);
1935 /* Propagate overflow flags. */
1936 if (overflow_p | TREE_OVERFLOW (arg1) | TREE_OVERFLOW (arg2))
1938 TREE_OVERFLOW (t) = 1;
1939 TREE_CONSTANT_OVERFLOW (t) = 1;
1941 else if (TREE_CONSTANT_OVERFLOW (arg1) | TREE_CONSTANT_OVERFLOW (arg2))
1942 TREE_CONSTANT_OVERFLOW (t) = 1;
1946 if (TREE_CODE (arg1) == COMPLEX_CST)
1948 tree type = TREE_TYPE (arg1);
1949 tree r1 = TREE_REALPART (arg1);
1950 tree i1 = TREE_IMAGPART (arg1);
1951 tree r2 = TREE_REALPART (arg2);
1952 tree i2 = TREE_IMAGPART (arg2);
1959 real = const_binop (code, r1, r2, notrunc);
1960 imag = const_binop (code, i1, i2, notrunc);
1964 real = const_binop (MINUS_EXPR,
1965 const_binop (MULT_EXPR, r1, r2, notrunc),
1966 const_binop (MULT_EXPR, i1, i2, notrunc),
1968 imag = const_binop (PLUS_EXPR,
1969 const_binop (MULT_EXPR, r1, i2, notrunc),
1970 const_binop (MULT_EXPR, i1, r2, notrunc),
1977 = const_binop (PLUS_EXPR,
1978 const_binop (MULT_EXPR, r2, r2, notrunc),
1979 const_binop (MULT_EXPR, i2, i2, notrunc),
1982 = const_binop (PLUS_EXPR,
1983 const_binop (MULT_EXPR, r1, r2, notrunc),
1984 const_binop (MULT_EXPR, i1, i2, notrunc),
1987 = const_binop (MINUS_EXPR,
1988 const_binop (MULT_EXPR, i1, r2, notrunc),
1989 const_binop (MULT_EXPR, r1, i2, notrunc),
1992 if (INTEGRAL_TYPE_P (TREE_TYPE (r1)))
1993 code = TRUNC_DIV_EXPR;
1995 real = const_binop (code, t1, magsquared, notrunc);
1996 imag = const_binop (code, t2, magsquared, notrunc);
2005 return build_complex (type, real, imag);
2011 /* Create a size type INT_CST node with NUMBER sign extended. KIND
2012 indicates which particular sizetype to create. */
2015 size_int_kind (HOST_WIDE_INT number, enum size_type_kind kind)
2017 return build_int_cst (sizetype_tab[(int) kind], number);
2020 /* Combine operands OP1 and OP2 with arithmetic operation CODE. CODE
2021 is a tree code. The type of the result is taken from the operands.
2022 Both must be equivalent integer types, ala int_binop_types_match_p.
2023 If the operands are constant, so is the result. */
2026 size_binop (enum tree_code code, tree arg0, tree arg1)
2028 tree type = TREE_TYPE (arg0);
2030 if (arg0 == error_mark_node || arg1 == error_mark_node)
2031 return error_mark_node;
2033 gcc_assert (int_binop_types_match_p (code, TREE_TYPE (arg0),
2036 /* Handle the special case of two integer constants faster. */
2037 if (TREE_CODE (arg0) == INTEGER_CST && TREE_CODE (arg1) == INTEGER_CST)
2039 /* And some specific cases even faster than that. */
2040 if (code == PLUS_EXPR)
2042 if (integer_zerop (arg0) && !TREE_OVERFLOW (arg0))
2044 if (integer_zerop (arg1) && !TREE_OVERFLOW (arg1))
2047 else if (code == MINUS_EXPR)
2049 if (integer_zerop (arg1) && !TREE_OVERFLOW (arg1))
2052 else if (code == MULT_EXPR)
2054 if (integer_onep (arg0) && !TREE_OVERFLOW (arg0))
2058 /* Handle general case of two integer constants. */
2059 return int_const_binop (code, arg0, arg1, 0);
2062 return fold_build2 (code, type, arg0, arg1);
2065 /* Given two values, either both of sizetype or both of bitsizetype,
2066 compute the difference between the two values. Return the value
2067 in signed type corresponding to the type of the operands. */
2070 size_diffop (tree arg0, tree arg1)
2072 tree type = TREE_TYPE (arg0);
2075 gcc_assert (int_binop_types_match_p (MINUS_EXPR, TREE_TYPE (arg0),
2078 /* If the type is already signed, just do the simple thing. */
2079 if (!TYPE_UNSIGNED (type))
2080 return size_binop (MINUS_EXPR, arg0, arg1);
2082 if (type == sizetype)
2084 else if (type == bitsizetype)
2085 ctype = sbitsizetype;
2087 ctype = signed_type_for (type);
2089 /* If either operand is not a constant, do the conversions to the signed
2090 type and subtract. The hardware will do the right thing with any
2091 overflow in the subtraction. */
2092 if (TREE_CODE (arg0) != INTEGER_CST || TREE_CODE (arg1) != INTEGER_CST)
2093 return size_binop (MINUS_EXPR, fold_convert (ctype, arg0),
2094 fold_convert (ctype, arg1));
2096 /* If ARG0 is larger than ARG1, subtract and return the result in CTYPE.
2097 Otherwise, subtract the other way, convert to CTYPE (we know that can't
2098 overflow) and negate (which can't either). Special-case a result
2099 of zero while we're here. */
2100 if (tree_int_cst_equal (arg0, arg1))
2101 return build_int_cst (ctype, 0);
2102 else if (tree_int_cst_lt (arg1, arg0))
2103 return fold_convert (ctype, size_binop (MINUS_EXPR, arg0, arg1));
2105 return size_binop (MINUS_EXPR, build_int_cst (ctype, 0),
2106 fold_convert (ctype, size_binop (MINUS_EXPR,
2110 /* A subroutine of fold_convert_const handling conversions of an
2111 INTEGER_CST to another integer type. */
2114 fold_convert_const_int_from_int (tree type, const_tree arg1)
2118 /* Given an integer constant, make new constant with new type,
2119 appropriately sign-extended or truncated. */
2120 t = force_fit_type_double (type, TREE_INT_CST_LOW (arg1),
2121 TREE_INT_CST_HIGH (arg1),
2122 /* Don't set the overflow when
2123 converting from a pointer, */
2124 !POINTER_TYPE_P (TREE_TYPE (arg1))
2125 /* or to a sizetype with same signedness
2126 and the precision is unchanged.
2127 ??? sizetype is always sign-extended,
2128 but its signedness depends on the
2129 frontend. Thus we see spurious overflows
2130 here if we do not check this. */
2131 && !((TYPE_PRECISION (TREE_TYPE (arg1))
2132 == TYPE_PRECISION (type))
2133 && (TYPE_UNSIGNED (TREE_TYPE (arg1))
2134 == TYPE_UNSIGNED (type))
2135 && ((TREE_CODE (TREE_TYPE (arg1)) == INTEGER_TYPE
2136 && TYPE_IS_SIZETYPE (TREE_TYPE (arg1)))
2137 || (TREE_CODE (type) == INTEGER_TYPE
2138 && TYPE_IS_SIZETYPE (type)))),
2139 (TREE_INT_CST_HIGH (arg1) < 0
2140 && (TYPE_UNSIGNED (type)
2141 < TYPE_UNSIGNED (TREE_TYPE (arg1))))
2142 | TREE_OVERFLOW (arg1));
2147 /* A subroutine of fold_convert_const handling conversions a REAL_CST
2148 to an integer type. */
2151 fold_convert_const_int_from_real (enum tree_code code, tree type, const_tree arg1)
2156 /* The following code implements the floating point to integer
2157 conversion rules required by the Java Language Specification,
2158 that IEEE NaNs are mapped to zero and values that overflow
2159 the target precision saturate, i.e. values greater than
2160 INT_MAX are mapped to INT_MAX, and values less than INT_MIN
2161 are mapped to INT_MIN. These semantics are allowed by the
2162 C and C++ standards that simply state that the behavior of
2163 FP-to-integer conversion is unspecified upon overflow. */
2165 HOST_WIDE_INT high, low;
2167 REAL_VALUE_TYPE x = TREE_REAL_CST (arg1);
2171 case FIX_TRUNC_EXPR:
2172 real_trunc (&r, VOIDmode, &x);
2179 /* If R is NaN, return zero and show we have an overflow. */
2180 if (REAL_VALUE_ISNAN (r))
2187 /* See if R is less than the lower bound or greater than the
2192 tree lt = TYPE_MIN_VALUE (type);
2193 REAL_VALUE_TYPE l = real_value_from_int_cst (NULL_TREE, lt);
2194 if (REAL_VALUES_LESS (r, l))
2197 high = TREE_INT_CST_HIGH (lt);
2198 low = TREE_INT_CST_LOW (lt);
2204 tree ut = TYPE_MAX_VALUE (type);
2207 REAL_VALUE_TYPE u = real_value_from_int_cst (NULL_TREE, ut);
2208 if (REAL_VALUES_LESS (u, r))
2211 high = TREE_INT_CST_HIGH (ut);
2212 low = TREE_INT_CST_LOW (ut);
2218 REAL_VALUE_TO_INT (&low, &high, r);
2220 t = force_fit_type_double (type, low, high, -1,
2221 overflow | TREE_OVERFLOW (arg1));
2225 /* A subroutine of fold_convert_const handling conversions of a
2226 FIXED_CST to an integer type. */
2229 fold_convert_const_int_from_fixed (tree type, const_tree arg1)
2232 double_int temp, temp_trunc;
2235 /* Right shift FIXED_CST to temp by fbit. */
2236 temp = TREE_FIXED_CST (arg1).data;
2237 mode = TREE_FIXED_CST (arg1).mode;
2238 if (GET_MODE_FBIT (mode) < 2 * HOST_BITS_PER_WIDE_INT)
2240 lshift_double (temp.low, temp.high,
2241 - GET_MODE_FBIT (mode), 2 * HOST_BITS_PER_WIDE_INT,
2242 &temp.low, &temp.high, SIGNED_FIXED_POINT_MODE_P (mode));
2244 /* Left shift temp to temp_trunc by fbit. */
2245 lshift_double (temp.low, temp.high,
2246 GET_MODE_FBIT (mode), 2 * HOST_BITS_PER_WIDE_INT,
2247 &temp_trunc.low, &temp_trunc.high,
2248 SIGNED_FIXED_POINT_MODE_P (mode));
2255 temp_trunc.high = 0;
2258 /* If FIXED_CST is negative, we need to round the value toward 0.
2259 By checking if the fractional bits are not zero to add 1 to temp. */
2260 if (SIGNED_FIXED_POINT_MODE_P (mode) && temp_trunc.high < 0
2261 && !double_int_equal_p (TREE_FIXED_CST (arg1).data, temp_trunc))
2266 temp = double_int_add (temp, one);
2269 /* Given a fixed-point constant, make new constant with new type,
2270 appropriately sign-extended or truncated. */
2271 t = force_fit_type_double (type, temp.low, temp.high, -1,
2273 && (TYPE_UNSIGNED (type)
2274 < TYPE_UNSIGNED (TREE_TYPE (arg1))))
2275 | TREE_OVERFLOW (arg1));
2280 /* A subroutine of fold_convert_const handling conversions a REAL_CST
2281 to another floating point type. */
2284 fold_convert_const_real_from_real (tree type, const_tree arg1)
2286 REAL_VALUE_TYPE value;
2289 real_convert (&value, TYPE_MODE (type), &TREE_REAL_CST (arg1));
2290 t = build_real (type, value);
2292 TREE_OVERFLOW (t) = TREE_OVERFLOW (arg1);
2296 /* A subroutine of fold_convert_const handling conversions a FIXED_CST
2297 to a floating point type. */
2300 fold_convert_const_real_from_fixed (tree type, const_tree arg1)
2302 REAL_VALUE_TYPE value;
2305 real_convert_from_fixed (&value, TYPE_MODE (type), &TREE_FIXED_CST (arg1));
2306 t = build_real (type, value);
2308 TREE_OVERFLOW (t) = TREE_OVERFLOW (arg1);
2309 TREE_CONSTANT_OVERFLOW (t)
2310 = TREE_OVERFLOW (t) | TREE_CONSTANT_OVERFLOW (arg1);
2314 /* A subroutine of fold_convert_const handling conversions a FIXED_CST
2315 to another fixed-point type. */
2318 fold_convert_const_fixed_from_fixed (tree type, const_tree arg1)
2320 FIXED_VALUE_TYPE value;
2324 overflow_p = fixed_convert (&value, TYPE_MODE (type), &TREE_FIXED_CST (arg1),
2325 TYPE_SATURATING (type));
2326 t = build_fixed (type, value);
2328 /* Propagate overflow flags. */
2329 if (overflow_p | TREE_OVERFLOW (arg1))
2331 TREE_OVERFLOW (t) = 1;
2332 TREE_CONSTANT_OVERFLOW (t) = 1;
2334 else if (TREE_CONSTANT_OVERFLOW (arg1))
2335 TREE_CONSTANT_OVERFLOW (t) = 1;
2339 /* A subroutine of fold_convert_const handling conversions an INTEGER_CST
2340 to a fixed-point type. */
2343 fold_convert_const_fixed_from_int (tree type, const_tree arg1)
2345 FIXED_VALUE_TYPE value;
2349 overflow_p = fixed_convert_from_int (&value, TYPE_MODE (type),
2350 TREE_INT_CST (arg1),
2351 TYPE_UNSIGNED (TREE_TYPE (arg1)),
2352 TYPE_SATURATING (type));
2353 t = build_fixed (type, value);
2355 /* Propagate overflow flags. */
2356 if (overflow_p | TREE_OVERFLOW (arg1))
2358 TREE_OVERFLOW (t) = 1;
2359 TREE_CONSTANT_OVERFLOW (t) = 1;
2361 else if (TREE_CONSTANT_OVERFLOW (arg1))
2362 TREE_CONSTANT_OVERFLOW (t) = 1;
2366 /* A subroutine of fold_convert_const handling conversions a REAL_CST
2367 to a fixed-point type. */
2370 fold_convert_const_fixed_from_real (tree type, const_tree arg1)
2372 FIXED_VALUE_TYPE value;
2376 overflow_p = fixed_convert_from_real (&value, TYPE_MODE (type),
2377 &TREE_REAL_CST (arg1),
2378 TYPE_SATURATING (type));
2379 t = build_fixed (type, value);
2381 /* Propagate overflow flags. */
2382 if (overflow_p | TREE_OVERFLOW (arg1))
2384 TREE_OVERFLOW (t) = 1;
2385 TREE_CONSTANT_OVERFLOW (t) = 1;
2387 else if (TREE_CONSTANT_OVERFLOW (arg1))
2388 TREE_CONSTANT_OVERFLOW (t) = 1;
2392 /* Attempt to fold type conversion operation CODE of expression ARG1 to
2393 type TYPE. If no simplification can be done return NULL_TREE. */
2396 fold_convert_const (enum tree_code code, tree type, tree arg1)
2398 if (TREE_TYPE (arg1) == type)
2401 if (POINTER_TYPE_P (type) || INTEGRAL_TYPE_P (type)
2402 || TREE_CODE (type) == OFFSET_TYPE)
2404 if (TREE_CODE (arg1) == INTEGER_CST)
2405 return fold_convert_const_int_from_int (type, arg1);
2406 else if (TREE_CODE (arg1) == REAL_CST)
2407 return fold_convert_const_int_from_real (code, type, arg1);
2408 else if (TREE_CODE (arg1) == FIXED_CST)
2409 return fold_convert_const_int_from_fixed (type, arg1);
2411 else if (TREE_CODE (type) == REAL_TYPE)
2413 if (TREE_CODE (arg1) == INTEGER_CST)
2414 return build_real_from_int_cst (type, arg1);
2415 else if (TREE_CODE (arg1) == REAL_CST)
2416 return fold_convert_const_real_from_real (type, arg1);
2417 else if (TREE_CODE (arg1) == FIXED_CST)
2418 return fold_convert_const_real_from_fixed (type, arg1);
2420 else if (TREE_CODE (type) == FIXED_POINT_TYPE)
2422 if (TREE_CODE (arg1) == FIXED_CST)
2423 return fold_convert_const_fixed_from_fixed (type, arg1);
2424 else if (TREE_CODE (arg1) == INTEGER_CST)
2425 return fold_convert_const_fixed_from_int (type, arg1);
2426 else if (TREE_CODE (arg1) == REAL_CST)
2427 return fold_convert_const_fixed_from_real (type, arg1);
2432 /* Construct a vector of zero elements of vector type TYPE. */
2435 build_zero_vector (tree type)
2440 elem = fold_convert_const (NOP_EXPR, TREE_TYPE (type), integer_zero_node);
2441 units = TYPE_VECTOR_SUBPARTS (type);
2444 for (i = 0; i < units; i++)
2445 list = tree_cons (NULL_TREE, elem, list);
2446 return build_vector (type, list);
2449 /* Returns true, if ARG is convertible to TYPE using a NOP_EXPR. */
2452 fold_convertible_p (const_tree type, const_tree arg)
2454 tree orig = TREE_TYPE (arg);
2459 if (TREE_CODE (arg) == ERROR_MARK
2460 || TREE_CODE (type) == ERROR_MARK
2461 || TREE_CODE (orig) == ERROR_MARK)
2464 if (TYPE_MAIN_VARIANT (type) == TYPE_MAIN_VARIANT (orig))
2467 switch (TREE_CODE (type))
2469 case INTEGER_TYPE: case ENUMERAL_TYPE: case BOOLEAN_TYPE:
2470 case POINTER_TYPE: case REFERENCE_TYPE:
2472 if (INTEGRAL_TYPE_P (orig) || POINTER_TYPE_P (orig)
2473 || TREE_CODE (orig) == OFFSET_TYPE)
2475 return (TREE_CODE (orig) == VECTOR_TYPE
2476 && tree_int_cst_equal (TYPE_SIZE (type), TYPE_SIZE (orig)));
2479 case FIXED_POINT_TYPE:
2483 return TREE_CODE (type) == TREE_CODE (orig);
2490 /* Convert expression ARG to type TYPE. Used by the middle-end for
2491 simple conversions in preference to calling the front-end's convert. */
2494 fold_convert (tree type, tree arg)
2496 tree orig = TREE_TYPE (arg);
2502 if (TREE_CODE (arg) == ERROR_MARK
2503 || TREE_CODE (type) == ERROR_MARK
2504 || TREE_CODE (orig) == ERROR_MARK)
2505 return error_mark_node;
2507 if (TYPE_MAIN_VARIANT (type) == TYPE_MAIN_VARIANT (orig))
2508 return fold_build1 (NOP_EXPR, type, arg);
2510 switch (TREE_CODE (type))
2512 case INTEGER_TYPE: case ENUMERAL_TYPE: case BOOLEAN_TYPE:
2513 case POINTER_TYPE: case REFERENCE_TYPE:
2515 if (TREE_CODE (arg) == INTEGER_CST)
2517 tem = fold_convert_const (NOP_EXPR, type, arg);
2518 if (tem != NULL_TREE)
2521 if (INTEGRAL_TYPE_P (orig) || POINTER_TYPE_P (orig)
2522 || TREE_CODE (orig) == OFFSET_TYPE)
2523 return fold_build1 (NOP_EXPR, type, arg);
2524 if (TREE_CODE (orig) == COMPLEX_TYPE)
2526 tem = fold_build1 (REALPART_EXPR, TREE_TYPE (orig), arg);
2527 return fold_convert (type, tem);
2529 gcc_assert (TREE_CODE (orig) == VECTOR_TYPE
2530 && tree_int_cst_equal (TYPE_SIZE (type), TYPE_SIZE (orig)));
2531 return fold_build1 (NOP_EXPR, type, arg);
2534 if (TREE_CODE (arg) == INTEGER_CST)
2536 tem = fold_convert_const (FLOAT_EXPR, type, arg);
2537 if (tem != NULL_TREE)
2540 else if (TREE_CODE (arg) == REAL_CST)
2542 tem = fold_convert_const (NOP_EXPR, type, arg);
2543 if (tem != NULL_TREE)
2546 else if (TREE_CODE (arg) == FIXED_CST)
2548 tem = fold_convert_const (FIXED_CONVERT_EXPR, type, arg);
2549 if (tem != NULL_TREE)
2553 switch (TREE_CODE (orig))
2556 case BOOLEAN_TYPE: case ENUMERAL_TYPE:
2557 case POINTER_TYPE: case REFERENCE_TYPE:
2558 return fold_build1 (FLOAT_EXPR, type, arg);
2561 return fold_build1 (NOP_EXPR, type, arg);
2563 case FIXED_POINT_TYPE:
2564 return fold_build1 (FIXED_CONVERT_EXPR, type, arg);
2567 tem = fold_build1 (REALPART_EXPR, TREE_TYPE (orig), arg);
2568 return fold_convert (type, tem);
2574 case FIXED_POINT_TYPE:
2575 if (TREE_CODE (arg) == FIXED_CST || TREE_CODE (arg) == INTEGER_CST
2576 || TREE_CODE (arg) == REAL_CST)
2578 tem = fold_convert_const (FIXED_CONVERT_EXPR, type, arg);
2579 if (tem != NULL_TREE)
2583 switch (TREE_CODE (orig))
2585 case FIXED_POINT_TYPE:
2590 return fold_build1 (FIXED_CONVERT_EXPR, type, arg);
2593 tem = fold_build1 (REALPART_EXPR, TREE_TYPE (orig), arg);
2594 return fold_convert (type, tem);
2601 switch (TREE_CODE (orig))
2604 case BOOLEAN_TYPE: case ENUMERAL_TYPE:
2605 case POINTER_TYPE: case REFERENCE_TYPE:
2607 case FIXED_POINT_TYPE:
2608 return build2 (COMPLEX_EXPR, type,
2609 fold_convert (TREE_TYPE (type), arg),
2610 fold_convert (TREE_TYPE (type), integer_zero_node));
2615 if (TREE_CODE (arg) == COMPLEX_EXPR)
2617 rpart = fold_convert (TREE_TYPE (type), TREE_OPERAND (arg, 0));
2618 ipart = fold_convert (TREE_TYPE (type), TREE_OPERAND (arg, 1));
2619 return fold_build2 (COMPLEX_EXPR, type, rpart, ipart);
2622 arg = save_expr (arg);
2623 rpart = fold_build1 (REALPART_EXPR, TREE_TYPE (orig), arg);
2624 ipart = fold_build1 (IMAGPART_EXPR, TREE_TYPE (orig), arg);
2625 rpart = fold_convert (TREE_TYPE (type), rpart);
2626 ipart = fold_convert (TREE_TYPE (type), ipart);
2627 return fold_build2 (COMPLEX_EXPR, type, rpart, ipart);
2635 if (integer_zerop (arg))
2636 return build_zero_vector (type);
2637 gcc_assert (tree_int_cst_equal (TYPE_SIZE (type), TYPE_SIZE (orig)));
2638 gcc_assert (INTEGRAL_TYPE_P (orig) || POINTER_TYPE_P (orig)
2639 || TREE_CODE (orig) == VECTOR_TYPE);
2640 return fold_build1 (VIEW_CONVERT_EXPR, type, arg);
2643 tem = fold_ignored_result (arg);
2644 if (TREE_CODE (tem) == MODIFY_EXPR)
2646 return fold_build1 (NOP_EXPR, type, tem);
2653 /* Return false if expr can be assumed not to be an lvalue, true
2657 maybe_lvalue_p (const_tree x)
2659 /* We only need to wrap lvalue tree codes. */
2660 switch (TREE_CODE (x))
2671 case ALIGN_INDIRECT_REF:
2672 case MISALIGNED_INDIRECT_REF:
2674 case ARRAY_RANGE_REF:
2680 case PREINCREMENT_EXPR:
2681 case PREDECREMENT_EXPR:
2683 case TRY_CATCH_EXPR:
2684 case WITH_CLEANUP_EXPR:
2695 /* Assume the worst for front-end tree codes. */
2696 if ((int)TREE_CODE (x) >= NUM_TREE_CODES)
2704 /* Return an expr equal to X but certainly not valid as an lvalue. */
2709 /* While we are in GIMPLE, NON_LVALUE_EXPR doesn't mean anything to
2714 if (! maybe_lvalue_p (x))
2716 return build1 (NON_LVALUE_EXPR, TREE_TYPE (x), x);
2719 /* Nonzero means lvalues are limited to those valid in pedantic ANSI C.
2720 Zero means allow extended lvalues. */
2722 int pedantic_lvalues;
2724 /* When pedantic, return an expr equal to X but certainly not valid as a
2725 pedantic lvalue. Otherwise, return X. */
2728 pedantic_non_lvalue (tree x)
2730 if (pedantic_lvalues)
2731 return non_lvalue (x);
2736 /* Given a tree comparison code, return the code that is the logical inverse
2737 of the given code. It is not safe to do this for floating-point
2738 comparisons, except for NE_EXPR and EQ_EXPR, so we receive a machine mode
2739 as well: if reversing the comparison is unsafe, return ERROR_MARK. */
2742 invert_tree_comparison (enum tree_code code, bool honor_nans)
2744 if (honor_nans && flag_trapping_math)
2754 return honor_nans ? UNLE_EXPR : LE_EXPR;
2756 return honor_nans ? UNLT_EXPR : LT_EXPR;
2758 return honor_nans ? UNGE_EXPR : GE_EXPR;
2760 return honor_nans ? UNGT_EXPR : GT_EXPR;
2774 return UNORDERED_EXPR;
2775 case UNORDERED_EXPR:
2776 return ORDERED_EXPR;
2782 /* Similar, but return the comparison that results if the operands are
2783 swapped. This is safe for floating-point. */
2786 swap_tree_comparison (enum tree_code code)
2793 case UNORDERED_EXPR:
2819 /* Convert a comparison tree code from an enum tree_code representation
2820 into a compcode bit-based encoding. This function is the inverse of
2821 compcode_to_comparison. */
2823 static enum comparison_code
2824 comparison_to_compcode (enum tree_code code)
2841 return COMPCODE_ORD;
2842 case UNORDERED_EXPR:
2843 return COMPCODE_UNORD;
2845 return COMPCODE_UNLT;
2847 return COMPCODE_UNEQ;
2849 return COMPCODE_UNLE;
2851 return COMPCODE_UNGT;
2853 return COMPCODE_LTGT;
2855 return COMPCODE_UNGE;
2861 /* Convert a compcode bit-based encoding of a comparison operator back
2862 to GCC's enum tree_code representation. This function is the
2863 inverse of comparison_to_compcode. */
2865 static enum tree_code
2866 compcode_to_comparison (enum comparison_code code)
2883 return ORDERED_EXPR;
2884 case COMPCODE_UNORD:
2885 return UNORDERED_EXPR;
2903 /* Return a tree for the comparison which is the combination of
2904 doing the AND or OR (depending on CODE) of the two operations LCODE
2905 and RCODE on the identical operands LL_ARG and LR_ARG. Take into account
2906 the possibility of trapping if the mode has NaNs, and return NULL_TREE
2907 if this makes the transformation invalid. */
2910 combine_comparisons (enum tree_code code, enum tree_code lcode,
2911 enum tree_code rcode, tree truth_type,
2912 tree ll_arg, tree lr_arg)
2914 bool honor_nans = HONOR_NANS (TYPE_MODE (TREE_TYPE (ll_arg)));
2915 enum comparison_code lcompcode = comparison_to_compcode (lcode);
2916 enum comparison_code rcompcode = comparison_to_compcode (rcode);
2917 enum comparison_code compcode;
2921 case TRUTH_AND_EXPR: case TRUTH_ANDIF_EXPR:
2922 compcode = lcompcode & rcompcode;
2925 case TRUTH_OR_EXPR: case TRUTH_ORIF_EXPR:
2926 compcode = lcompcode | rcompcode;
2935 /* Eliminate unordered comparisons, as well as LTGT and ORD
2936 which are not used unless the mode has NaNs. */
2937 compcode &= ~COMPCODE_UNORD;
2938 if (compcode == COMPCODE_LTGT)
2939 compcode = COMPCODE_NE;
2940 else if (compcode == COMPCODE_ORD)
2941 compcode = COMPCODE_TRUE;
2943 else if (flag_trapping_math)
2945 /* Check that the original operation and the optimized ones will trap
2946 under the same condition. */
2947 bool ltrap = (lcompcode & COMPCODE_UNORD) == 0
2948 && (lcompcode != COMPCODE_EQ)
2949 && (lcompcode != COMPCODE_ORD);
2950 bool rtrap = (rcompcode & COMPCODE_UNORD) == 0
2951 && (rcompcode != COMPCODE_EQ)
2952 && (rcompcode != COMPCODE_ORD);
2953 bool trap = (compcode & COMPCODE_UNORD) == 0
2954 && (compcode != COMPCODE_EQ)
2955 && (compcode != COMPCODE_ORD);
2957 /* In a short-circuited boolean expression the LHS might be
2958 such that the RHS, if evaluated, will never trap. For
2959 example, in ORD (x, y) && (x < y), we evaluate the RHS only
2960 if neither x nor y is NaN. (This is a mixed blessing: for
2961 example, the expression above will never trap, hence
2962 optimizing it to x < y would be invalid). */
2963 if ((code == TRUTH_ORIF_EXPR && (lcompcode & COMPCODE_UNORD))
2964 || (code == TRUTH_ANDIF_EXPR && !(lcompcode & COMPCODE_UNORD)))
2967 /* If the comparison was short-circuited, and only the RHS
2968 trapped, we may now generate a spurious trap. */
2970 && (code == TRUTH_ANDIF_EXPR || code == TRUTH_ORIF_EXPR))
2973 /* If we changed the conditions that cause a trap, we lose. */
2974 if ((ltrap || rtrap) != trap)
2978 if (compcode == COMPCODE_TRUE)
2979 return constant_boolean_node (true, truth_type);
2980 else if (compcode == COMPCODE_FALSE)
2981 return constant_boolean_node (false, truth_type);
2983 return fold_build2 (compcode_to_comparison (compcode),
2984 truth_type, ll_arg, lr_arg);
2987 /* Return nonzero if two operands (typically of the same tree node)
2988 are necessarily equal. If either argument has side-effects this
2989 function returns zero. FLAGS modifies behavior as follows:
2991 If OEP_ONLY_CONST is set, only return nonzero for constants.
2992 This function tests whether the operands are indistinguishable;
2993 it does not test whether they are equal using C's == operation.
2994 The distinction is important for IEEE floating point, because
2995 (1) -0.0 and 0.0 are distinguishable, but -0.0==0.0, and
2996 (2) two NaNs may be indistinguishable, but NaN!=NaN.
2998 If OEP_ONLY_CONST is unset, a VAR_DECL is considered equal to itself
2999 even though it may hold multiple values during a function.
3000 This is because a GCC tree node guarantees that nothing else is
3001 executed between the evaluation of its "operands" (which may often
3002 be evaluated in arbitrary order). Hence if the operands themselves
3003 don't side-effect, the VAR_DECLs, PARM_DECLs etc... must hold the
3004 same value in each operand/subexpression. Hence leaving OEP_ONLY_CONST
3005 unset means assuming isochronic (or instantaneous) tree equivalence.
3006 Unless comparing arbitrary expression trees, such as from different
3007 statements, this flag can usually be left unset.
3009 If OEP_PURE_SAME is set, then pure functions with identical arguments
3010 are considered the same. It is used when the caller has other ways
3011 to ensure that global memory is unchanged in between. */
3014 operand_equal_p (const_tree arg0, const_tree arg1, unsigned int flags)
3016 /* If either is ERROR_MARK, they aren't equal. */
3017 if (TREE_CODE (arg0) == ERROR_MARK || TREE_CODE (arg1) == ERROR_MARK)
3020 /* Check equality of integer constants before bailing out due to
3021 precision differences. */
3022 if (TREE_CODE (arg0) == INTEGER_CST && TREE_CODE (arg1) == INTEGER_CST)
3023 return tree_int_cst_equal (arg0, arg1);
3025 /* If both types don't have the same signedness, then we can't consider
3026 them equal. We must check this before the STRIP_NOPS calls
3027 because they may change the signedness of the arguments. As pointers
3028 strictly don't have a signedness, require either two pointers or
3029 two non-pointers as well. */
3030 if (TYPE_UNSIGNED (TREE_TYPE (arg0)) != TYPE_UNSIGNED (TREE_TYPE (arg1))
3031 || POINTER_TYPE_P (TREE_TYPE (arg0)) != POINTER_TYPE_P (TREE_TYPE (arg1)))
3034 /* If both types don't have the same precision, then it is not safe
3036 if (TYPE_PRECISION (TREE_TYPE (arg0)) != TYPE_PRECISION (TREE_TYPE (arg1)))
3042 /* In case both args are comparisons but with different comparison
3043 code, try to swap the comparison operands of one arg to produce
3044 a match and compare that variant. */
3045 if (TREE_CODE (arg0) != TREE_CODE (arg1)
3046 && COMPARISON_CLASS_P (arg0)
3047 && COMPARISON_CLASS_P (arg1))
3049 enum tree_code swap_code = swap_tree_comparison (TREE_CODE (arg1));
3051 if (TREE_CODE (arg0) == swap_code)
3052 return operand_equal_p (TREE_OPERAND (arg0, 0),
3053 TREE_OPERAND (arg1, 1), flags)
3054 && operand_equal_p (TREE_OPERAND (arg0, 1),
3055 TREE_OPERAND (arg1, 0), flags);
3058 if (TREE_CODE (arg0) != TREE_CODE (arg1)
3059 /* This is needed for conversions and for COMPONENT_REF.
3060 Might as well play it safe and always test this. */
3061 || TREE_CODE (TREE_TYPE (arg0)) == ERROR_MARK
3062 || TREE_CODE (TREE_TYPE (arg1)) == ERROR_MARK
3063 || TYPE_MODE (TREE_TYPE (arg0)) != TYPE_MODE (TREE_TYPE (arg1)))
3066 /* If ARG0 and ARG1 are the same SAVE_EXPR, they are necessarily equal.
3067 We don't care about side effects in that case because the SAVE_EXPR
3068 takes care of that for us. In all other cases, two expressions are
3069 equal if they have no side effects. If we have two identical
3070 expressions with side effects that should be treated the same due
3071 to the only side effects being identical SAVE_EXPR's, that will
3072 be detected in the recursive calls below. */
3073 if (arg0 == arg1 && ! (flags & OEP_ONLY_CONST)
3074 && (TREE_CODE (arg0) == SAVE_EXPR
3075 || (! TREE_SIDE_EFFECTS (arg0) && ! TREE_SIDE_EFFECTS (arg1))))
3078 /* Next handle constant cases, those for which we can return 1 even
3079 if ONLY_CONST is set. */
3080 if (TREE_CONSTANT (arg0) && TREE_CONSTANT (arg1))
3081 switch (TREE_CODE (arg0))
3084 return tree_int_cst_equal (arg0, arg1);
3087 return FIXED_VALUES_IDENTICAL (TREE_FIXED_CST (arg0),
3088 TREE_FIXED_CST (arg1));
3091 if (REAL_VALUES_IDENTICAL (TREE_REAL_CST (arg0),
3092 TREE_REAL_CST (arg1)))
3096 if (!HONOR_SIGNED_ZEROS (TYPE_MODE (TREE_TYPE (arg0))))
3098 /* If we do not distinguish between signed and unsigned zero,
3099 consider them equal. */
3100 if (real_zerop (arg0) && real_zerop (arg1))
3109 v1 = TREE_VECTOR_CST_ELTS (arg0);
3110 v2 = TREE_VECTOR_CST_ELTS (arg1);
3113 if (!operand_equal_p (TREE_VALUE (v1), TREE_VALUE (v2),
3116 v1 = TREE_CHAIN (v1);
3117 v2 = TREE_CHAIN (v2);
3124 return (operand_equal_p (TREE_REALPART (arg0), TREE_REALPART (arg1),
3126 && operand_equal_p (TREE_IMAGPART (arg0), TREE_IMAGPART (arg1),
3130 return (TREE_STRING_LENGTH (arg0) == TREE_STRING_LENGTH (arg1)
3131 && ! memcmp (TREE_STRING_POINTER (arg0),
3132 TREE_STRING_POINTER (arg1),
3133 TREE_STRING_LENGTH (arg0)));
3136 return operand_equal_p (TREE_OPERAND (arg0, 0), TREE_OPERAND (arg1, 0),
3142 if (flags & OEP_ONLY_CONST)
3145 /* Define macros to test an operand from arg0 and arg1 for equality and a
3146 variant that allows null and views null as being different from any
3147 non-null value. In the latter case, if either is null, the both
3148 must be; otherwise, do the normal comparison. */
3149 #define OP_SAME(N) operand_equal_p (TREE_OPERAND (arg0, N), \
3150 TREE_OPERAND (arg1, N), flags)
3152 #define OP_SAME_WITH_NULL(N) \
3153 ((!TREE_OPERAND (arg0, N) || !TREE_OPERAND (arg1, N)) \
3154 ? TREE_OPERAND (arg0, N) == TREE_OPERAND (arg1, N) : OP_SAME (N))
3156 switch (TREE_CODE_CLASS (TREE_CODE (arg0)))
3159 /* Two conversions are equal only if signedness and modes match. */
3160 switch (TREE_CODE (arg0))
3163 case FIX_TRUNC_EXPR:
3164 if (TYPE_UNSIGNED (TREE_TYPE (arg0))
3165 != TYPE_UNSIGNED (TREE_TYPE (arg1)))
3175 case tcc_comparison:
3177 if (OP_SAME (0) && OP_SAME (1))
3180 /* For commutative ops, allow the other order. */
3181 return (commutative_tree_code (TREE_CODE (arg0))
3182 && operand_equal_p (TREE_OPERAND (arg0, 0),
3183 TREE_OPERAND (arg1, 1), flags)
3184 && operand_equal_p (TREE_OPERAND (arg0, 1),
3185 TREE_OPERAND (arg1, 0), flags));
3188 /* If either of the pointer (or reference) expressions we are
3189 dereferencing contain a side effect, these cannot be equal. */
3190 if (TREE_SIDE_EFFECTS (arg0)
3191 || TREE_SIDE_EFFECTS (arg1))
3194 switch (TREE_CODE (arg0))
3197 case ALIGN_INDIRECT_REF:
3198 case MISALIGNED_INDIRECT_REF:
3204 case ARRAY_RANGE_REF:
3205 /* Operands 2 and 3 may be null.
3206 Compare the array index by value if it is constant first as we
3207 may have different types but same value here. */
3209 && (tree_int_cst_equal (TREE_OPERAND (arg0, 1),
3210 TREE_OPERAND (arg1, 1))
3212 && OP_SAME_WITH_NULL (2)
3213 && OP_SAME_WITH_NULL (3));
3216 /* Handle operand 2 the same as for ARRAY_REF. Operand 0
3217 may be NULL when we're called to compare MEM_EXPRs. */
3218 return OP_SAME_WITH_NULL (0)
3220 && OP_SAME_WITH_NULL (2);
3223 return OP_SAME (0) && OP_SAME (1) && OP_SAME (2);
3229 case tcc_expression:
3230 switch (TREE_CODE (arg0))
3233 case TRUTH_NOT_EXPR:
3236 case TRUTH_ANDIF_EXPR:
3237 case TRUTH_ORIF_EXPR:
3238 return OP_SAME (0) && OP_SAME (1);
3240 case TRUTH_AND_EXPR:
3242 case TRUTH_XOR_EXPR:
3243 if (OP_SAME (0) && OP_SAME (1))
3246 /* Otherwise take into account this is a commutative operation. */
3247 return (operand_equal_p (TREE_OPERAND (arg0, 0),
3248 TREE_OPERAND (arg1, 1), flags)
3249 && operand_equal_p (TREE_OPERAND (arg0, 1),
3250 TREE_OPERAND (arg1, 0), flags));
3253 return OP_SAME (0) && OP_SAME (1) && OP_SAME (2);
3260 switch (TREE_CODE (arg0))
3263 /* If the CALL_EXPRs call different functions, then they
3264 clearly can not be equal. */
3265 if (! operand_equal_p (CALL_EXPR_FN (arg0), CALL_EXPR_FN (arg1),
3270 unsigned int cef = call_expr_flags (arg0);
3271 if (flags & OEP_PURE_SAME)
3272 cef &= ECF_CONST | ECF_PURE;
3279 /* Now see if all the arguments are the same. */
3281 const_call_expr_arg_iterator iter0, iter1;
3283 for (a0 = first_const_call_expr_arg (arg0, &iter0),
3284 a1 = first_const_call_expr_arg (arg1, &iter1);
3286 a0 = next_const_call_expr_arg (&iter0),
3287 a1 = next_const_call_expr_arg (&iter1))
3288 if (! operand_equal_p (a0, a1, flags))
3291 /* If we get here and both argument lists are exhausted
3292 then the CALL_EXPRs are equal. */
3293 return ! (a0 || a1);
3299 case tcc_declaration:
3300 /* Consider __builtin_sqrt equal to sqrt. */
3301 return (TREE_CODE (arg0) == FUNCTION_DECL
3302 && DECL_BUILT_IN (arg0) && DECL_BUILT_IN (arg1)
3303 && DECL_BUILT_IN_CLASS (arg0) == DECL_BUILT_IN_CLASS (arg1)
3304 && DECL_FUNCTION_CODE (arg0) == DECL_FUNCTION_CODE (arg1));
3311 #undef OP_SAME_WITH_NULL
3314 /* Similar to operand_equal_p, but see if ARG0 might have been made by
3315 shorten_compare from ARG1 when ARG1 was being compared with OTHER.
3317 When in doubt, return 0. */
3320 operand_equal_for_comparison_p (tree arg0, tree arg1, tree other)
3322 int unsignedp1, unsignedpo;
3323 tree primarg0, primarg1, primother;
3324 unsigned int correct_width;
3326 if (operand_equal_p (arg0, arg1, 0))
3329 if (! INTEGRAL_TYPE_P (TREE_TYPE (arg0))
3330 || ! INTEGRAL_TYPE_P (TREE_TYPE (arg1)))
3333 /* Discard any conversions that don't change the modes of ARG0 and ARG1
3334 and see if the inner values are the same. This removes any
3335 signedness comparison, which doesn't matter here. */
3336 primarg0 = arg0, primarg1 = arg1;
3337 STRIP_NOPS (primarg0);
3338 STRIP_NOPS (primarg1);
3339 if (operand_equal_p (primarg0, primarg1, 0))
3342 /* Duplicate what shorten_compare does to ARG1 and see if that gives the
3343 actual comparison operand, ARG0.
3345 First throw away any conversions to wider types
3346 already present in the operands. */
3348 primarg1 = get_narrower (arg1, &unsignedp1);
3349 primother = get_narrower (other, &unsignedpo);
3351 correct_width = TYPE_PRECISION (TREE_TYPE (arg1));
3352 if (unsignedp1 == unsignedpo
3353 && TYPE_PRECISION (TREE_TYPE (primarg1)) < correct_width
3354 && TYPE_PRECISION (TREE_TYPE (primother)) < correct_width)
3356 tree type = TREE_TYPE (arg0);
3358 /* Make sure shorter operand is extended the right way
3359 to match the longer operand. */
3360 primarg1 = fold_convert (signed_or_unsigned_type_for
3361 (unsignedp1, TREE_TYPE (primarg1)), primarg1);
3363 if (operand_equal_p (arg0, fold_convert (type, primarg1), 0))
3370 /* See if ARG is an expression that is either a comparison or is performing
3371 arithmetic on comparisons. The comparisons must only be comparing
3372 two different values, which will be stored in *CVAL1 and *CVAL2; if
3373 they are nonzero it means that some operands have already been found.
3374 No variables may be used anywhere else in the expression except in the
3375 comparisons. If SAVE_P is true it means we removed a SAVE_EXPR around
3376 the expression and save_expr needs to be called with CVAL1 and CVAL2.
3378 If this is true, return 1. Otherwise, return zero. */
3381 twoval_comparison_p (tree arg, tree *cval1, tree *cval2, int *save_p)
3383 enum tree_code code = TREE_CODE (arg);
3384 enum tree_code_class tclass = TREE_CODE_CLASS (code);
3386 /* We can handle some of the tcc_expression cases here. */
3387 if (tclass == tcc_expression && code == TRUTH_NOT_EXPR)
3389 else if (tclass == tcc_expression
3390 && (code == TRUTH_ANDIF_EXPR || code == TRUTH_ORIF_EXPR
3391 || code == COMPOUND_EXPR))
3392 tclass = tcc_binary;
3394 else if (tclass == tcc_expression && code == SAVE_EXPR
3395 && ! TREE_SIDE_EFFECTS (TREE_OPERAND (arg, 0)))
3397 /* If we've already found a CVAL1 or CVAL2, this expression is
3398 two complex to handle. */
3399 if (*cval1 || *cval2)
3409 return twoval_comparison_p (TREE_OPERAND (arg, 0), cval1, cval2, save_p);
3412 return (twoval_comparison_p (TREE_OPERAND (arg, 0), cval1, cval2, save_p)
3413 && twoval_comparison_p (TREE_OPERAND (arg, 1),
3414 cval1, cval2, save_p));
3419 case tcc_expression:
3420 if (code == COND_EXPR)
3421 return (twoval_comparison_p (TREE_OPERAND (arg, 0),
3422 cval1, cval2, save_p)
3423 && twoval_comparison_p (TREE_OPERAND (arg, 1),
3424 cval1, cval2, save_p)
3425 && twoval_comparison_p (TREE_OPERAND (arg, 2),
3426 cval1, cval2, save_p));
3429 case tcc_comparison:
3430 /* First see if we can handle the first operand, then the second. For
3431 the second operand, we know *CVAL1 can't be zero. It must be that
3432 one side of the comparison is each of the values; test for the
3433 case where this isn't true by failing if the two operands
3436 if (operand_equal_p (TREE_OPERAND (arg, 0),
3437 TREE_OPERAND (arg, 1), 0))
3441 *cval1 = TREE_OPERAND (arg, 0);
3442 else if (operand_equal_p (*cval1, TREE_OPERAND (arg, 0), 0))
3444 else if (*cval2 == 0)
3445 *cval2 = TREE_OPERAND (arg, 0);
3446 else if (operand_equal_p (*cval2, TREE_OPERAND (arg, 0), 0))
3451 if (operand_equal_p (*cval1, TREE_OPERAND (arg, 1), 0))
3453 else if (*cval2 == 0)
3454 *cval2 = TREE_OPERAND (arg, 1);
3455 else if (operand_equal_p (*cval2, TREE_OPERAND (arg, 1), 0))
3467 /* ARG is a tree that is known to contain just arithmetic operations and
3468 comparisons. Evaluate the operations in the tree substituting NEW0 for
3469 any occurrence of OLD0 as an operand of a comparison and likewise for
3473 eval_subst (tree arg, tree old0, tree new0, tree old1, tree new1)
3475 tree type = TREE_TYPE (arg);
3476 enum tree_code code = TREE_CODE (arg);
3477 enum tree_code_class tclass = TREE_CODE_CLASS (code);
3479 /* We can handle some of the tcc_expression cases here. */
3480 if (tclass == tcc_expression && code == TRUTH_NOT_EXPR)
3482 else if (tclass == tcc_expression
3483 && (code == TRUTH_ANDIF_EXPR || code == TRUTH_ORIF_EXPR))
3484 tclass = tcc_binary;
3489 return fold_build1 (code, type,
3490 eval_subst (TREE_OPERAND (arg, 0),
3491 old0, new0, old1, new1));
3494 return fold_build2 (code, type,
3495 eval_subst (TREE_OPERAND (arg, 0),
3496 old0, new0, old1, new1),
3497 eval_subst (TREE_OPERAND (arg, 1),
3498 old0, new0, old1, new1));
3500 case tcc_expression:
3504 return eval_subst (TREE_OPERAND (arg, 0), old0, new0, old1, new1);
3507 return eval_subst (TREE_OPERAND (arg, 1), old0, new0, old1, new1);
3510 return fold_build3 (code, type,
3511 eval_subst (TREE_OPERAND (arg, 0),
3512 old0, new0, old1, new1),
3513 eval_subst (TREE_OPERAND (arg, 1),
3514 old0, new0, old1, new1),
3515 eval_subst (TREE_OPERAND (arg, 2),
3516 old0, new0, old1, new1));
3520 /* Fall through - ??? */
3522 case tcc_comparison:
3524 tree arg0 = TREE_OPERAND (arg, 0);
3525 tree arg1 = TREE_OPERAND (arg, 1);
3527 /* We need to check both for exact equality and tree equality. The
3528 former will be true if the operand has a side-effect. In that
3529 case, we know the operand occurred exactly once. */
3531 if (arg0 == old0 || operand_equal_p (arg0, old0, 0))
3533 else if (arg0 == old1 || operand_equal_p (arg0, old1, 0))
3536 if (arg1 == old0 || operand_equal_p (arg1, old0, 0))
3538 else if (arg1 == old1 || operand_equal_p (arg1, old1, 0))
3541 return fold_build2 (code, type, arg0, arg1);
3549 /* Return a tree for the case when the result of an expression is RESULT
3550 converted to TYPE and OMITTED was previously an operand of the expression
3551 but is now not needed (e.g., we folded OMITTED * 0).
3553 If OMITTED has side effects, we must evaluate it. Otherwise, just do
3554 the conversion of RESULT to TYPE. */
3557 omit_one_operand (tree type, tree result, tree omitted)
3559 tree t = fold_convert (type, result);
3561 /* If the resulting operand is an empty statement, just return the omitted
3562 statement casted to void. */
3563 if (IS_EMPTY_STMT (t) && TREE_SIDE_EFFECTS (omitted))
3564 return build1 (NOP_EXPR, void_type_node, fold_ignored_result (omitted));
3566 if (TREE_SIDE_EFFECTS (omitted))
3567 return build2 (COMPOUND_EXPR, type, fold_ignored_result (omitted), t);
3569 return non_lvalue (t);
3572 /* Similar, but call pedantic_non_lvalue instead of non_lvalue. */
3575 pedantic_omit_one_operand (tree type, tree result, tree omitted)
3577 tree t = fold_convert (type, result);
3579 /* If the resulting operand is an empty statement, just return the omitted
3580 statement casted to void. */
3581 if (IS_EMPTY_STMT (t) && TREE_SIDE_EFFECTS (omitted))
3582 return build1 (NOP_EXPR, void_type_node, fold_ignored_result (omitted));
3584 if (TREE_SIDE_EFFECTS (omitted))
3585 return build2 (COMPOUND_EXPR, type, fold_ignored_result (omitted), t);
3587 return pedantic_non_lvalue (t);
3590 /* Return a tree for the case when the result of an expression is RESULT
3591 converted to TYPE and OMITTED1 and OMITTED2 were previously operands
3592 of the expression but are now not needed.
3594 If OMITTED1 or OMITTED2 has side effects, they must be evaluated.
3595 If both OMITTED1 and OMITTED2 have side effects, OMITTED1 is
3596 evaluated before OMITTED2. Otherwise, if neither has side effects,
3597 just do the conversion of RESULT to TYPE. */
3600 omit_two_operands (tree type, tree result, tree omitted1, tree omitted2)
3602 tree t = fold_convert (type, result);
3604 if (TREE_SIDE_EFFECTS (omitted2))
3605 t = build2 (COMPOUND_EXPR, type, omitted2, t);
3606 if (TREE_SIDE_EFFECTS (omitted1))
3607 t = build2 (COMPOUND_EXPR, type, omitted1, t);
3609 return TREE_CODE (t) != COMPOUND_EXPR ? non_lvalue (t) : t;
3613 /* Return a simplified tree node for the truth-negation of ARG. This
3614 never alters ARG itself. We assume that ARG is an operation that
3615 returns a truth value (0 or 1).
3617 FIXME: one would think we would fold the result, but it causes
3618 problems with the dominator optimizer. */
3621 fold_truth_not_expr (tree arg)
3623 tree type = TREE_TYPE (arg);
3624 enum tree_code code = TREE_CODE (arg);
3626 /* If this is a comparison, we can simply invert it, except for
3627 floating-point non-equality comparisons, in which case we just
3628 enclose a TRUTH_NOT_EXPR around what we have. */
3630 if (TREE_CODE_CLASS (code) == tcc_comparison)
3632 tree op_type = TREE_TYPE (TREE_OPERAND (arg, 0));
3633 if (FLOAT_TYPE_P (op_type)
3634 && flag_trapping_math
3635 && code != ORDERED_EXPR && code != UNORDERED_EXPR
3636 && code != NE_EXPR && code != EQ_EXPR)
3640 code = invert_tree_comparison (code,
3641 HONOR_NANS (TYPE_MODE (op_type)));
3642 if (code == ERROR_MARK)
3645 return build2 (code, type,
3646 TREE_OPERAND (arg, 0), TREE_OPERAND (arg, 1));
3653 return constant_boolean_node (integer_zerop (arg), type);
3655 case TRUTH_AND_EXPR:
3656 return build2 (TRUTH_OR_EXPR, type,
3657 invert_truthvalue (TREE_OPERAND (arg, 0)),
3658 invert_truthvalue (TREE_OPERAND (arg, 1)));
3661 return build2 (TRUTH_AND_EXPR, type,
3662 invert_truthvalue (TREE_OPERAND (arg, 0)),
3663 invert_truthvalue (TREE_OPERAND (arg, 1)));
3665 case TRUTH_XOR_EXPR:
3666 /* Here we can invert either operand. We invert the first operand
3667 unless the second operand is a TRUTH_NOT_EXPR in which case our
3668 result is the XOR of the first operand with the inside of the
3669 negation of the second operand. */
3671 if (TREE_CODE (TREE_OPERAND (arg, 1)) == TRUTH_NOT_EXPR)
3672 return build2 (TRUTH_XOR_EXPR, type, TREE_OPERAND (arg, 0),
3673 TREE_OPERAND (TREE_OPERAND (arg, 1), 0));
3675 return build2 (TRUTH_XOR_EXPR, type,
3676 invert_truthvalue (TREE_OPERAND (arg, 0)),
3677 TREE_OPERAND (arg, 1));
3679 case TRUTH_ANDIF_EXPR:
3680 return build2 (TRUTH_ORIF_EXPR, type,
3681 invert_truthvalue (TREE_OPERAND (arg, 0)),
3682 invert_truthvalue (TREE_OPERAND (arg, 1)));
3684 case TRUTH_ORIF_EXPR:
3685 return build2 (TRUTH_ANDIF_EXPR, type,
3686 invert_truthvalue (TREE_OPERAND (arg, 0)),
3687 invert_truthvalue (TREE_OPERAND (arg, 1)));
3689 case TRUTH_NOT_EXPR:
3690 return TREE_OPERAND (arg, 0);
3694 tree arg1 = TREE_OPERAND (arg, 1);
3695 tree arg2 = TREE_OPERAND (arg, 2);
3696 /* A COND_EXPR may have a throw as one operand, which
3697 then has void type. Just leave void operands
3699 return build3 (COND_EXPR, type, TREE_OPERAND (arg, 0),
3700 VOID_TYPE_P (TREE_TYPE (arg1))
3701 ? arg1 : invert_truthvalue (arg1),
3702 VOID_TYPE_P (TREE_TYPE (arg2))
3703 ? arg2 : invert_truthvalue (arg2));
3707 return build2 (COMPOUND_EXPR, type, TREE_OPERAND (arg, 0),
3708 invert_truthvalue (TREE_OPERAND (arg, 1)));
3710 case NON_LVALUE_EXPR:
3711 return invert_truthvalue (TREE_OPERAND (arg, 0));
3714 if (TREE_CODE (TREE_TYPE (arg)) == BOOLEAN_TYPE)
3715 return build1 (TRUTH_NOT_EXPR, type, arg);
3719 return build1 (TREE_CODE (arg), type,
3720 invert_truthvalue (TREE_OPERAND (arg, 0)));
3723 if (!integer_onep (TREE_OPERAND (arg, 1)))
3725 return build2 (EQ_EXPR, type, arg,
3726 build_int_cst (type, 0));
3729 return build1 (TRUTH_NOT_EXPR, type, arg);
3731 case CLEANUP_POINT_EXPR:
3732 return build1 (CLEANUP_POINT_EXPR, type,
3733 invert_truthvalue (TREE_OPERAND (arg, 0)));
3742 /* Return a simplified tree node for the truth-negation of ARG. This
3743 never alters ARG itself. We assume that ARG is an operation that
3744 returns a truth value (0 or 1).
3746 FIXME: one would think we would fold the result, but it causes
3747 problems with the dominator optimizer. */
3750 invert_truthvalue (tree arg)
3754 if (TREE_CODE (arg) == ERROR_MARK)
3757 tem = fold_truth_not_expr (arg);
3759 tem = build1 (TRUTH_NOT_EXPR, TREE_TYPE (arg), arg);
3764 /* Given a bit-wise operation CODE applied to ARG0 and ARG1, see if both
3765 operands are another bit-wise operation with a common input. If so,
3766 distribute the bit operations to save an operation and possibly two if
3767 constants are involved. For example, convert
3768 (A | B) & (A | C) into A | (B & C)
3769 Further simplification will occur if B and C are constants.
3771 If this optimization cannot be done, 0 will be returned. */
3774 distribute_bit_expr (enum tree_code code, tree type, tree arg0, tree arg1)
3779 if (TREE_CODE (arg0) != TREE_CODE (arg1)
3780 || TREE_CODE (arg0) == code
3781 || (TREE_CODE (arg0) != BIT_AND_EXPR
3782 && TREE_CODE (arg0) != BIT_IOR_EXPR))
3785 if (operand_equal_p (TREE_OPERAND (arg0, 0), TREE_OPERAND (arg1, 0), 0))
3787 common = TREE_OPERAND (arg0, 0);
3788 left = TREE_OPERAND (arg0, 1);
3789 right = TREE_OPERAND (arg1, 1);
3791 else if (operand_equal_p (TREE_OPERAND (arg0, 0), TREE_OPERAND (arg1, 1), 0))
3793 common = TREE_OPERAND (arg0, 0);
3794 left = TREE_OPERAND (arg0, 1);
3795 right = TREE_OPERAND (arg1, 0);
3797 else if (operand_equal_p (TREE_OPERAND (arg0, 1), TREE_OPERAND (arg1, 0), 0))
3799 common = TREE_OPERAND (arg0, 1);
3800 left = TREE_OPERAND (arg0, 0);
3801 right = TREE_OPERAND (arg1, 1);
3803 else if (operand_equal_p (TREE_OPERAND (arg0, 1), TREE_OPERAND (arg1, 1), 0))
3805 common = TREE_OPERAND (arg0, 1);
3806 left = TREE_OPERAND (arg0, 0);
3807 right = TREE_OPERAND (arg1, 0);
3812 common = fold_convert (type, common);
3813 left = fold_convert (type, left);
3814 right = fold_convert (type, right);
3815 return fold_build2 (TREE_CODE (arg0), type, common,
3816 fold_build2 (code, type, left, right));
3819 /* Knowing that ARG0 and ARG1 are both RDIV_EXPRs, simplify a binary operation
3820 with code CODE. This optimization is unsafe. */
3822 distribute_real_division (enum tree_code code, tree type, tree arg0, tree arg1)
3824 bool mul0 = TREE_CODE (arg0) == MULT_EXPR;
3825 bool mul1 = TREE_CODE (arg1) == MULT_EXPR;
3827 /* (A / C) +- (B / C) -> (A +- B) / C. */
3829 && operand_equal_p (TREE_OPERAND (arg0, 1),
3830 TREE_OPERAND (arg1, 1), 0))
3831 return fold_build2 (mul0 ? MULT_EXPR : RDIV_EXPR, type,
3832 fold_build2 (code, type,
3833 TREE_OPERAND (arg0, 0),
3834 TREE_OPERAND (arg1, 0)),
3835 TREE_OPERAND (arg0, 1));
3837 /* (A / C1) +- (A / C2) -> A * (1 / C1 +- 1 / C2). */
3838 if (operand_equal_p (TREE_OPERAND (arg0, 0),
3839 TREE_OPERAND (arg1, 0), 0)
3840 && TREE_CODE (TREE_OPERAND (arg0, 1)) == REAL_CST
3841 && TREE_CODE (TREE_OPERAND (arg1, 1)) == REAL_CST)
3843 REAL_VALUE_TYPE r0, r1;
3844 r0 = TREE_REAL_CST (TREE_OPERAND (arg0, 1));
3845 r1 = TREE_REAL_CST (TREE_OPERAND (arg1, 1));
3847 real_arithmetic (&r0, RDIV_EXPR, &dconst1, &r0);
3849 real_arithmetic (&r1, RDIV_EXPR, &dconst1, &r1);
3850 real_arithmetic (&r0, code, &r0, &r1);
3851 return fold_build2 (MULT_EXPR, type,
3852 TREE_OPERAND (arg0, 0),
3853 build_real (type, r0));
3859 /* Return a BIT_FIELD_REF of type TYPE to refer to BITSIZE bits of INNER
3860 starting at BITPOS. The field is unsigned if UNSIGNEDP is nonzero. */
3863 make_bit_field_ref (tree inner, tree type, HOST_WIDE_INT bitsize,
3864 HOST_WIDE_INT bitpos, int unsignedp)
3866 tree result, bftype;
3870 tree size = TYPE_SIZE (TREE_TYPE (inner));
3871 if ((INTEGRAL_TYPE_P (TREE_TYPE (inner))
3872 || POINTER_TYPE_P (TREE_TYPE (inner)))
3873 && host_integerp (size, 0)
3874 && tree_low_cst (size, 0) == bitsize)
3875 return fold_convert (type, inner);
3879 if (TYPE_PRECISION (bftype) != bitsize
3880 || TYPE_UNSIGNED (bftype) == !unsignedp)
3881 bftype = build_nonstandard_integer_type (bitsize, 0);
3883 result = build3 (BIT_FIELD_REF, bftype, inner,
3884 size_int (bitsize), bitsize_int (bitpos));
3887 result = fold_convert (type, result);
3892 /* Optimize a bit-field compare.
3894 There are two cases: First is a compare against a constant and the
3895 second is a comparison of two items where the fields are at the same
3896 bit position relative to the start of a chunk (byte, halfword, word)
3897 large enough to contain it. In these cases we can avoid the shift
3898 implicit in bitfield extractions.
3900 For constants, we emit a compare of the shifted constant with the
3901 BIT_AND_EXPR of a mask and a byte, halfword, or word of the operand being
3902 compared. For two fields at the same position, we do the ANDs with the
3903 similar mask and compare the result of the ANDs.
3905 CODE is the comparison code, known to be either NE_EXPR or EQ_EXPR.
3906 COMPARE_TYPE is the type of the comparison, and LHS and RHS
3907 are the left and right operands of the comparison, respectively.
3909 If the optimization described above can be done, we return the resulting
3910 tree. Otherwise we return zero. */
3913 optimize_bit_field_compare (enum tree_code code, tree compare_type,
3916 HOST_WIDE_INT lbitpos, lbitsize, rbitpos, rbitsize, nbitpos, nbitsize;
3917 tree type = TREE_TYPE (lhs);
3918 tree signed_type, unsigned_type;
3919 int const_p = TREE_CODE (rhs) == INTEGER_CST;
3920 enum machine_mode lmode, rmode, nmode;
3921 int lunsignedp, runsignedp;
3922 int lvolatilep = 0, rvolatilep = 0;
3923 tree linner, rinner = NULL_TREE;
3927 /* Get all the information about the extractions being done. If the bit size
3928 if the same as the size of the underlying object, we aren't doing an
3929 extraction at all and so can do nothing. We also don't want to
3930 do anything if the inner expression is a PLACEHOLDER_EXPR since we
3931 then will no longer be able to replace it. */
3932 linner = get_inner_reference (lhs, &lbitsize, &lbitpos, &offset, &lmode,
3933 &lunsignedp, &lvolatilep, false);
3934 if (linner == lhs || lbitsize == GET_MODE_BITSIZE (lmode) || lbitsize < 0
3935 || offset != 0 || TREE_CODE (linner) == PLACEHOLDER_EXPR)
3940 /* If this is not a constant, we can only do something if bit positions,
3941 sizes, and signedness are the same. */
3942 rinner = get_inner_reference (rhs, &rbitsize, &rbitpos, &offset, &rmode,
3943 &runsignedp, &rvolatilep, false);
3945 if (rinner == rhs || lbitpos != rbitpos || lbitsize != rbitsize
3946 || lunsignedp != runsignedp || offset != 0
3947 || TREE_CODE (rinner) == PLACEHOLDER_EXPR)
3951 /* See if we can find a mode to refer to this field. We should be able to,
3952 but fail if we can't. */
3953 nmode = get_best_mode (lbitsize, lbitpos,
3954 const_p ? TYPE_ALIGN (TREE_TYPE (linner))
3955 : MIN (TYPE_ALIGN (TREE_TYPE (linner)),
3956 TYPE_ALIGN (TREE_TYPE (rinner))),
3957 word_mode, lvolatilep || rvolatilep);
3958 if (nmode == VOIDmode)
3961 /* Set signed and unsigned types of the precision of this mode for the
3963 signed_type = lang_hooks.types.type_for_mode (nmode, 0);
3964 unsigned_type = lang_hooks.types.type_for_mode (nmode, 1);
3966 /* Compute the bit position and size for the new reference and our offset
3967 within it. If the new reference is the same size as the original, we
3968 won't optimize anything, so return zero. */
3969 nbitsize = GET_MODE_BITSIZE (nmode);
3970 nbitpos = lbitpos & ~ (nbitsize - 1);
3972 if (nbitsize == lbitsize)
3975 if (BYTES_BIG_ENDIAN)
3976 lbitpos = nbitsize - lbitsize - lbitpos;
3978 /* Make the mask to be used against the extracted field. */
3979 mask = build_int_cst_type (unsigned_type, -1);
3980 mask = const_binop (LSHIFT_EXPR, mask, size_int (nbitsize - lbitsize), 0);
3981 mask = const_binop (RSHIFT_EXPR, mask,
3982 size_int (nbitsize - lbitsize - lbitpos), 0);
3985 /* If not comparing with constant, just rework the comparison
3987 return fold_build2 (code, compare_type,
3988 fold_build2 (BIT_AND_EXPR, unsigned_type,
3989 make_bit_field_ref (linner,
3994 fold_build2 (BIT_AND_EXPR, unsigned_type,
3995 make_bit_field_ref (rinner,
4001 /* Otherwise, we are handling the constant case. See if the constant is too
4002 big for the field. Warn and return a tree of for 0 (false) if so. We do
4003 this not only for its own sake, but to avoid having to test for this
4004 error case below. If we didn't, we might generate wrong code.
4006 For unsigned fields, the constant shifted right by the field length should
4007 be all zero. For signed fields, the high-order bits should agree with
4012 if (! integer_zerop (const_binop (RSHIFT_EXPR,
4013 fold_convert (unsigned_type, rhs),
4014 size_int (lbitsize), 0)))
4016 warning (0, "comparison is always %d due to width of bit-field",
4018 return constant_boolean_node (code == NE_EXPR, compare_type);
4023 tree tem = const_binop (RSHIFT_EXPR, fold_convert (signed_type, rhs),
4024 size_int (lbitsize - 1), 0);
4025 if (! integer_zerop (tem) && ! integer_all_onesp (tem))
4027 warning (0, "comparison is always %d due to width of bit-field",
4029 return constant_boolean_node (code == NE_EXPR, compare_type);
4033 /* Single-bit compares should always be against zero. */
4034 if (lbitsize == 1 && ! integer_zerop (rhs))
4036 code = code == EQ_EXPR ? NE_EXPR : EQ_EXPR;
4037 rhs = build_int_cst (type, 0);
4040 /* Make a new bitfield reference, shift the constant over the
4041 appropriate number of bits and mask it with the computed mask
4042 (in case this was a signed field). If we changed it, make a new one. */
4043 lhs = make_bit_field_ref (linner, unsigned_type, nbitsize, nbitpos, 1);
4046 TREE_SIDE_EFFECTS (lhs) = 1;
4047 TREE_THIS_VOLATILE (lhs) = 1;
4050 rhs = const_binop (BIT_AND_EXPR,
4051 const_binop (LSHIFT_EXPR,
4052 fold_convert (unsigned_type, rhs),
4053 size_int (lbitpos), 0),
4056 return build2 (code, compare_type,
4057 build2 (BIT_AND_EXPR, unsigned_type, lhs, mask),
4061 /* Subroutine for fold_truthop: decode a field reference.
4063 If EXP is a comparison reference, we return the innermost reference.
4065 *PBITSIZE is set to the number of bits in the reference, *PBITPOS is
4066 set to the starting bit number.
4068 If the innermost field can be completely contained in a mode-sized
4069 unit, *PMODE is set to that mode. Otherwise, it is set to VOIDmode.
4071 *PVOLATILEP is set to 1 if the any expression encountered is volatile;
4072 otherwise it is not changed.
4074 *PUNSIGNEDP is set to the signedness of the field.
4076 *PMASK is set to the mask used. This is either contained in a
4077 BIT_AND_EXPR or derived from the width of the field.
4079 *PAND_MASK is set to the mask found in a BIT_AND_EXPR, if any.
4081 Return 0 if this is not a component reference or is one that we can't
4082 do anything with. */
4085 decode_field_reference (tree exp, HOST_WIDE_INT *pbitsize,
4086 HOST_WIDE_INT *pbitpos, enum machine_mode *pmode,
4087 int *punsignedp, int *pvolatilep,
4088 tree *pmask, tree *pand_mask)
4090 tree outer_type = 0;
4092 tree mask, inner, offset;
4094 unsigned int precision;
4096 /* All the optimizations using this function assume integer fields.
4097 There are problems with FP fields since the type_for_size call
4098 below can fail for, e.g., XFmode. */
4099 if (! INTEGRAL_TYPE_P (TREE_TYPE (exp)))
4102 /* We are interested in the bare arrangement of bits, so strip everything
4103 that doesn't affect the machine mode. However, record the type of the
4104 outermost expression if it may matter below. */
4105 if (CONVERT_EXPR_P (exp)
4106 || TREE_CODE (exp) == NON_LVALUE_EXPR)
4107 outer_type = TREE_TYPE (exp);
4110 if (TREE_CODE (exp) == BIT_AND_EXPR)
4112 and_mask = TREE_OPERAND (exp, 1);
4113 exp = TREE_OPERAND (exp, 0);
4114 STRIP_NOPS (exp); STRIP_NOPS (and_mask);
4115 if (TREE_CODE (and_mask) != INTEGER_CST)
4119 inner = get_inner_reference (exp, pbitsize, pbitpos, &offset, pmode,
4120 punsignedp, pvolatilep, false);
4121 if ((inner == exp && and_mask == 0)
4122 || *pbitsize < 0 || offset != 0
4123 || TREE_CODE (inner) == PLACEHOLDER_EXPR)
4126 /* If the number of bits in the reference is the same as the bitsize of
4127 the outer type, then the outer type gives the signedness. Otherwise
4128 (in case of a small bitfield) the signedness is unchanged. */
4129 if (outer_type && *pbitsize == TYPE_PRECISION (outer_type))
4130 *punsignedp = TYPE_UNSIGNED (outer_type);
4132 /* Compute the mask to access the bitfield. */
4133 unsigned_type = lang_hooks.types.type_for_size (*pbitsize, 1);
4134 precision = TYPE_PRECISION (unsigned_type);
4136 mask = build_int_cst_type (unsigned_type, -1);
4138 mask = const_binop (LSHIFT_EXPR, mask, size_int (precision - *pbitsize), 0);
4139 mask = const_binop (RSHIFT_EXPR, mask, size_int (precision - *pbitsize), 0);
4141 /* Merge it with the mask we found in the BIT_AND_EXPR, if any. */
4143 mask = fold_build2 (BIT_AND_EXPR, unsigned_type,
4144 fold_convert (unsigned_type, and_mask), mask);
4147 *pand_mask = and_mask;
4151 /* Return nonzero if MASK represents a mask of SIZE ones in the low-order
4155 all_ones_mask_p (const_tree mask, int size)
4157 tree type = TREE_TYPE (mask);
4158 unsigned int precision = TYPE_PRECISION (type);
4161 tmask = build_int_cst_type (signed_type_for (type), -1);
4164 tree_int_cst_equal (mask,
4165 const_binop (RSHIFT_EXPR,
4166 const_binop (LSHIFT_EXPR, tmask,
4167 size_int (precision - size),
4169 size_int (precision - size), 0));
4172 /* Subroutine for fold: determine if VAL is the INTEGER_CONST that
4173 represents the sign bit of EXP's type. If EXP represents a sign
4174 or zero extension, also test VAL against the unextended type.
4175 The return value is the (sub)expression whose sign bit is VAL,
4176 or NULL_TREE otherwise. */
4179 sign_bit_p (tree exp, const_tree val)
4181 unsigned HOST_WIDE_INT mask_lo, lo;
4182 HOST_WIDE_INT mask_hi, hi;
4186 /* Tree EXP must have an integral type. */
4187 t = TREE_TYPE (exp);
4188 if (! INTEGRAL_TYPE_P (t))
4191 /* Tree VAL must be an integer constant. */
4192 if (TREE_CODE (val) != INTEGER_CST
4193 || TREE_OVERFLOW (val))
4196 width = TYPE_PRECISION (t);
4197 if (width > HOST_BITS_PER_WIDE_INT)
4199 hi = (unsigned HOST_WIDE_INT) 1 << (width - HOST_BITS_PER_WIDE_INT - 1);
4202 mask_hi = ((unsigned HOST_WIDE_INT) -1
4203 >> (2 * HOST_BITS_PER_WIDE_INT - width));
4209 lo = (unsigned HOST_WIDE_INT) 1 << (width - 1);
4212 mask_lo = ((unsigned HOST_WIDE_INT) -1
4213 >> (HOST_BITS_PER_WIDE_INT - width));
4216 /* We mask off those bits beyond TREE_TYPE (exp) so that we can
4217 treat VAL as if it were unsigned. */
4218 if ((TREE_INT_CST_HIGH (val) & mask_hi) == hi
4219 && (TREE_INT_CST_LOW (val) & mask_lo) == lo)
4222 /* Handle extension from a narrower type. */
4223 if (TREE_CODE (exp) == NOP_EXPR
4224 && TYPE_PRECISION (TREE_TYPE (TREE_OPERAND (exp, 0))) < width)
4225 return sign_bit_p (TREE_OPERAND (exp, 0), val);
4230 /* Subroutine for fold_truthop: determine if an operand is simple enough
4231 to be evaluated unconditionally. */
4234 simple_operand_p (const_tree exp)
4236 /* Strip any conversions that don't change the machine mode. */
4239 return (CONSTANT_CLASS_P (exp)
4240 || TREE_CODE (exp) == SSA_NAME
4242 && ! TREE_ADDRESSABLE (exp)
4243 && ! TREE_THIS_VOLATILE (exp)
4244 && ! DECL_NONLOCAL (exp)
4245 /* Don't regard global variables as simple. They may be
4246 allocated in ways unknown to the compiler (shared memory,
4247 #pragma weak, etc). */
4248 && ! TREE_PUBLIC (exp)
4249 && ! DECL_EXTERNAL (exp)
4250 /* Loading a static variable is unduly expensive, but global
4251 registers aren't expensive. */
4252 && (! TREE_STATIC (exp) || DECL_REGISTER (exp))));
4255 /* The following functions are subroutines to fold_range_test and allow it to
4256 try to change a logical combination of comparisons into a range test.
4259 X == 2 || X == 3 || X == 4 || X == 5
4263 (unsigned) (X - 2) <= 3
4265 We describe each set of comparisons as being either inside or outside
4266 a range, using a variable named like IN_P, and then describe the
4267 range with a lower and upper bound. If one of the bounds is omitted,
4268 it represents either the highest or lowest value of the type.
4270 In the comments below, we represent a range by two numbers in brackets
4271 preceded by a "+" to designate being inside that range, or a "-" to
4272 designate being outside that range, so the condition can be inverted by
4273 flipping the prefix. An omitted bound is represented by a "-". For
4274 example, "- [-, 10]" means being outside the range starting at the lowest
4275 possible value and ending at 10, in other words, being greater than 10.
4276 The range "+ [-, -]" is always true and hence the range "- [-, -]" is
4279 We set up things so that the missing bounds are handled in a consistent
4280 manner so neither a missing bound nor "true" and "false" need to be
4281 handled using a special case. */
4283 /* Return the result of applying CODE to ARG0 and ARG1, but handle the case
4284 of ARG0 and/or ARG1 being omitted, meaning an unlimited range. UPPER0_P
4285 and UPPER1_P are nonzero if the respective argument is an upper bound
4286 and zero for a lower. TYPE, if nonzero, is the type of the result; it
4287 must be specified for a comparison. ARG1 will be converted to ARG0's
4288 type if both are specified. */
4291 range_binop (enum tree_code code, tree type, tree arg0, int upper0_p,
4292 tree arg1, int upper1_p)
4298 /* If neither arg represents infinity, do the normal operation.
4299 Else, if not a comparison, return infinity. Else handle the special
4300 comparison rules. Note that most of the cases below won't occur, but
4301 are handled for consistency. */
4303 if (arg0 != 0 && arg1 != 0)
4305 tem = fold_build2 (code, type != 0 ? type : TREE_TYPE (arg0),
4306 arg0, fold_convert (TREE_TYPE (arg0), arg1));
4308 return TREE_CODE (tem) == INTEGER_CST ? tem : 0;
4311 if (TREE_CODE_CLASS (code) != tcc_comparison)
4314 /* Set SGN[01] to -1 if ARG[01] is a lower bound, 1 for upper, and 0
4315 for neither. In real maths, we cannot assume open ended ranges are
4316 the same. But, this is computer arithmetic, where numbers are finite.
4317 We can therefore make the transformation of any unbounded range with
4318 the value Z, Z being greater than any representable number. This permits
4319 us to treat unbounded ranges as equal. */
4320 sgn0 = arg0 != 0 ? 0 : (upper0_p ? 1 : -1);
4321 sgn1 = arg1 != 0 ? 0 : (upper1_p ? 1 : -1);
4325 result = sgn0 == sgn1;
4328 result = sgn0 != sgn1;
4331 result = sgn0 < sgn1;
4334 result = sgn0 <= sgn1;
4337 result = sgn0 > sgn1;
4340 result = sgn0 >= sgn1;
4346 return constant_boolean_node (result, type);
4349 /* Given EXP, a logical expression, set the range it is testing into
4350 variables denoted by PIN_P, PLOW, and PHIGH. Return the expression
4351 actually being tested. *PLOW and *PHIGH will be made of the same
4352 type as the returned expression. If EXP is not a comparison, we
4353 will most likely not be returning a useful value and range. Set
4354 *STRICT_OVERFLOW_P to true if the return value is only valid
4355 because signed overflow is undefined; otherwise, do not change
4356 *STRICT_OVERFLOW_P. */
4359 make_range (tree exp, int *pin_p, tree *plow, tree *phigh,
4360 bool *strict_overflow_p)
4362 enum tree_code code;
4363 tree arg0 = NULL_TREE, arg1 = NULL_TREE;
4364 tree exp_type = NULL_TREE, arg0_type = NULL_TREE;
4366 tree low, high, n_low, n_high;
4368 /* Start with simply saying "EXP != 0" and then look at the code of EXP
4369 and see if we can refine the range. Some of the cases below may not
4370 happen, but it doesn't seem worth worrying about this. We "continue"
4371 the outer loop when we've changed something; otherwise we "break"
4372 the switch, which will "break" the while. */
4375 low = high = build_int_cst (TREE_TYPE (exp), 0);
4379 code = TREE_CODE (exp);
4380 exp_type = TREE_TYPE (exp);
4382 if (IS_EXPR_CODE_CLASS (TREE_CODE_CLASS (code)))
4384 if (TREE_OPERAND_LENGTH (exp) > 0)
4385 arg0 = TREE_OPERAND (exp, 0);
4386 if (TREE_CODE_CLASS (code) == tcc_comparison
4387 || TREE_CODE_CLASS (code) == tcc_unary
4388 || TREE_CODE_CLASS (code) == tcc_binary)
4389 arg0_type = TREE_TYPE (arg0);
4390 if (TREE_CODE_CLASS (code) == tcc_binary
4391 || TREE_CODE_CLASS (code) == tcc_comparison
4392 || (TREE_CODE_CLASS (code) == tcc_expression
4393 && TREE_OPERAND_LENGTH (exp) > 1))
4394 arg1 = TREE_OPERAND (exp, 1);
4399 case TRUTH_NOT_EXPR:
4400 in_p = ! in_p, exp = arg0;
4403 case EQ_EXPR: case NE_EXPR:
4404 case LT_EXPR: case LE_EXPR: case GE_EXPR: case GT_EXPR:
4405 /* We can only do something if the range is testing for zero
4406 and if the second operand is an integer constant. Note that
4407 saying something is "in" the range we make is done by
4408 complementing IN_P since it will set in the initial case of
4409 being not equal to zero; "out" is leaving it alone. */
4410 if (low == 0 || high == 0
4411 || ! integer_zerop (low) || ! integer_zerop (high)
4412 || TREE_CODE (arg1) != INTEGER_CST)
4417 case NE_EXPR: /* - [c, c] */
4420 case EQ_EXPR: /* + [c, c] */
4421 in_p = ! in_p, low = high = arg1;
4423 case GT_EXPR: /* - [-, c] */
4424 low = 0, high = arg1;
4426 case GE_EXPR: /* + [c, -] */
4427 in_p = ! in_p, low = arg1, high = 0;
4429 case LT_EXPR: /* - [c, -] */
4430 low = arg1, high = 0;
4432 case LE_EXPR: /* + [-, c] */
4433 in_p = ! in_p, low = 0, high = arg1;
4439 /* If this is an unsigned comparison, we also know that EXP is
4440 greater than or equal to zero. We base the range tests we make
4441 on that fact, so we record it here so we can parse existing
4442 range tests. We test arg0_type since often the return type
4443 of, e.g. EQ_EXPR, is boolean. */
4444 if (TYPE_UNSIGNED (arg0_type) && (low == 0 || high == 0))
4446 if (! merge_ranges (&n_in_p, &n_low, &n_high,
4448 build_int_cst (arg0_type, 0),
4452 in_p = n_in_p, low = n_low, high = n_high;
4454 /* If the high bound is missing, but we have a nonzero low
4455 bound, reverse the range so it goes from zero to the low bound
4457 if (high == 0 && low && ! integer_zerop (low))
4460 high = range_binop (MINUS_EXPR, NULL_TREE, low, 0,
4461 integer_one_node, 0);
4462 low = build_int_cst (arg0_type, 0);
4470 /* (-x) IN [a,b] -> x in [-b, -a] */
4471 n_low = range_binop (MINUS_EXPR, exp_type,
4472 build_int_cst (exp_type, 0),
4474 n_high = range_binop (MINUS_EXPR, exp_type,
4475 build_int_cst (exp_type, 0),
4477 low = n_low, high = n_high;
4483 exp = build2 (MINUS_EXPR, exp_type, negate_expr (arg0),
4484 build_int_cst (exp_type, 1));
4487 case PLUS_EXPR: case MINUS_EXPR:
4488 if (TREE_CODE (arg1) != INTEGER_CST)
4491 /* If flag_wrapv and ARG0_TYPE is signed, then we cannot
4492 move a constant to the other side. */
4493 if (!TYPE_UNSIGNED (arg0_type)
4494 && !TYPE_OVERFLOW_UNDEFINED (arg0_type))
4497 /* If EXP is signed, any overflow in the computation is undefined,
4498 so we don't worry about it so long as our computations on
4499 the bounds don't overflow. For unsigned, overflow is defined
4500 and this is exactly the right thing. */
4501 n_low = range_binop (code == MINUS_EXPR ? PLUS_EXPR : MINUS_EXPR,
4502 arg0_type, low, 0, arg1, 0);
4503 n_high = range_binop (code == MINUS_EXPR ? PLUS_EXPR : MINUS_EXPR,
4504 arg0_type, high, 1, arg1, 0);
4505 if ((n_low != 0 && TREE_OVERFLOW (n_low))
4506 || (n_high != 0 && TREE_OVERFLOW (n_high)))
4509 if (TYPE_OVERFLOW_UNDEFINED (arg0_type))
4510 *strict_overflow_p = true;
4512 /* Check for an unsigned range which has wrapped around the maximum
4513 value thus making n_high < n_low, and normalize it. */
4514 if (n_low && n_high && tree_int_cst_lt (n_high, n_low))
4516 low = range_binop (PLUS_EXPR, arg0_type, n_high, 0,
4517 integer_one_node, 0);
4518 high = range_binop (MINUS_EXPR, arg0_type, n_low, 0,
4519 integer_one_node, 0);
4521 /* If the range is of the form +/- [ x+1, x ], we won't
4522 be able to normalize it. But then, it represents the
4523 whole range or the empty set, so make it
4525 if (tree_int_cst_equal (n_low, low)
4526 && tree_int_cst_equal (n_high, high))
4532 low = n_low, high = n_high;
4537 CASE_CONVERT: case NON_LVALUE_EXPR:
4538 if (TYPE_PRECISION (arg0_type) > TYPE_PRECISION (exp_type))
4541 if (! INTEGRAL_TYPE_P (arg0_type)
4542 || (low != 0 && ! int_fits_type_p (low, arg0_type))
4543 || (high != 0 && ! int_fits_type_p (high, arg0_type)))
4546 n_low = low, n_high = high;
4549 n_low = fold_convert (arg0_type, n_low);
4552 n_high = fold_convert (arg0_type, n_high);
4555 /* If we're converting arg0 from an unsigned type, to exp,
4556 a signed type, we will be doing the comparison as unsigned.
4557 The tests above have already verified that LOW and HIGH
4560 So we have to ensure that we will handle large unsigned
4561 values the same way that the current signed bounds treat
4564 if (!TYPE_UNSIGNED (exp_type) && TYPE_UNSIGNED (arg0_type))
4568 /* For fixed-point modes, we need to pass the saturating flag
4569 as the 2nd parameter. */
4570 if (ALL_FIXED_POINT_MODE_P (TYPE_MODE (arg0_type)))
4571 equiv_type = lang_hooks.types.type_for_mode
4572 (TYPE_MODE (arg0_type),
4573 TYPE_SATURATING (arg0_type));
4575 equiv_type = lang_hooks.types.type_for_mode
4576 (TYPE_MODE (arg0_type), 1);
4578 /* A range without an upper bound is, naturally, unbounded.
4579 Since convert would have cropped a very large value, use
4580 the max value for the destination type. */
4582 = TYPE_MAX_VALUE (equiv_type) ? TYPE_MAX_VALUE (equiv_type)
4583 : TYPE_MAX_VALUE (arg0_type);
4585 if (TYPE_PRECISION (exp_type) == TYPE_PRECISION (arg0_type))
4586 high_positive = fold_build2 (RSHIFT_EXPR, arg0_type,
4587 fold_convert (arg0_type,
4589 build_int_cst (arg0_type, 1));
4591 /* If the low bound is specified, "and" the range with the
4592 range for which the original unsigned value will be
4596 if (! merge_ranges (&n_in_p, &n_low, &n_high,
4597 1, n_low, n_high, 1,
4598 fold_convert (arg0_type,
4603 in_p = (n_in_p == in_p);
4607 /* Otherwise, "or" the range with the range of the input
4608 that will be interpreted as negative. */
4609 if (! merge_ranges (&n_in_p, &n_low, &n_high,
4610 0, n_low, n_high, 1,
4611 fold_convert (arg0_type,
4616 in_p = (in_p != n_in_p);
4621 low = n_low, high = n_high;
4631 /* If EXP is a constant, we can evaluate whether this is true or false. */
4632 if (TREE_CODE (exp) == INTEGER_CST)
4634 in_p = in_p == (integer_onep (range_binop (GE_EXPR, integer_type_node,
4636 && integer_onep (range_binop (LE_EXPR, integer_type_node,
4642 *pin_p = in_p, *plow = low, *phigh = high;
4646 /* Given a range, LOW, HIGH, and IN_P, an expression, EXP, and a result
4647 type, TYPE, return an expression to test if EXP is in (or out of, depending
4648 on IN_P) the range. Return 0 if the test couldn't be created. */
4651 build_range_check (tree type, tree exp, int in_p, tree low, tree high)
4653 tree etype = TREE_TYPE (exp);
4656 #ifdef HAVE_canonicalize_funcptr_for_compare
4657 /* Disable this optimization for function pointer expressions
4658 on targets that require function pointer canonicalization. */
4659 if (HAVE_canonicalize_funcptr_for_compare
4660 && TREE_CODE (etype) == POINTER_TYPE
4661 && TREE_CODE (TREE_TYPE (etype)) == FUNCTION_TYPE)
4667 value = build_range_check (type, exp, 1, low, high);
4669 return invert_truthvalue (value);
4674 if (low == 0 && high == 0)
4675 return build_int_cst (type, 1);
4678 return fold_build2 (LE_EXPR, type, exp,
4679 fold_convert (etype, high));
4682 return fold_build2 (GE_EXPR, type, exp,
4683 fold_convert (etype, low));
4685 if (operand_equal_p (low, high, 0))
4686 return fold_build2 (EQ_EXPR, type, exp,
4687 fold_convert (etype, low));
4689 if (integer_zerop (low))
4691 if (! TYPE_UNSIGNED (etype))
4693 etype = unsigned_type_for (etype);
4694 high = fold_convert (etype, high);
4695 exp = fold_convert (etype, exp);
4697 return build_range_check (type, exp, 1, 0, high);
4700 /* Optimize (c>=1) && (c<=127) into (signed char)c > 0. */
4701 if (integer_onep (low) && TREE_CODE (high) == INTEGER_CST)
4703 unsigned HOST_WIDE_INT lo;
4707 prec = TYPE_PRECISION (etype);
4708 if (prec <= HOST_BITS_PER_WIDE_INT)
4711 lo = ((unsigned HOST_WIDE_INT) 1 << (prec - 1)) - 1;
4715 hi = ((HOST_WIDE_INT) 1 << (prec - HOST_BITS_PER_WIDE_INT - 1)) - 1;
4716 lo = (unsigned HOST_WIDE_INT) -1;
4719 if (TREE_INT_CST_HIGH (high) == hi && TREE_INT_CST_LOW (high) == lo)
4721 if (TYPE_UNSIGNED (etype))
4723 tree signed_etype = signed_type_for (etype);
4724 if (TYPE_PRECISION (signed_etype) != TYPE_PRECISION (etype))
4726 = build_nonstandard_integer_type (TYPE_PRECISION (etype), 0);
4728 etype = signed_etype;
4729 exp = fold_convert (etype, exp);
4731 return fold_build2 (GT_EXPR, type, exp,
4732 build_int_cst (etype, 0));
4736 /* Optimize (c>=low) && (c<=high) into (c-low>=0) && (c-low<=high-low).
4737 This requires wrap-around arithmetics for the type of the expression. */
4738 switch (TREE_CODE (etype))
4741 /* There is no requirement that LOW be within the range of ETYPE
4742 if the latter is a subtype. It must, however, be within the base
4743 type of ETYPE. So be sure we do the subtraction in that type. */
4744 if (TREE_TYPE (etype))
4745 etype = TREE_TYPE (etype);
4750 etype = lang_hooks.types.type_for_size (TYPE_PRECISION (etype),
4751 TYPE_UNSIGNED (etype));
4758 /* If we don't have wrap-around arithmetics upfront, try to force it. */
4759 if (TREE_CODE (etype) == INTEGER_TYPE
4760 && !TYPE_OVERFLOW_WRAPS (etype))
4762 tree utype, minv, maxv;
4764 /* Check if (unsigned) INT_MAX + 1 == (unsigned) INT_MIN
4765 for the type in question, as we rely on this here. */
4766 utype = unsigned_type_for (etype);
4767 maxv = fold_convert (utype, TYPE_MAX_VALUE (etype));
4768 maxv = range_binop (PLUS_EXPR, NULL_TREE, maxv, 1,
4769 integer_one_node, 1);
4770 minv = fold_convert (utype, TYPE_MIN_VALUE (etype));
4772 if (integer_zerop (range_binop (NE_EXPR, integer_type_node,
4779 high = fold_convert (etype, high);
4780 low = fold_convert (etype, low);
4781 exp = fold_convert (etype, exp);
4783 value = const_binop (MINUS_EXPR, high, low, 0);
4786 if (POINTER_TYPE_P (etype))
4788 if (value != 0 && !TREE_OVERFLOW (value))
4790 low = fold_convert (sizetype, low);
4791 low = fold_build1 (NEGATE_EXPR, sizetype, low);
4792 return build_range_check (type,
4793 fold_build2 (POINTER_PLUS_EXPR, etype, exp, low),
4794 1, build_int_cst (etype, 0), value);
4799 if (value != 0 && !TREE_OVERFLOW (value))
4800 return build_range_check (type,
4801 fold_build2 (MINUS_EXPR, etype, exp, low),
4802 1, build_int_cst (etype, 0), value);
4807 /* Return the predecessor of VAL in its type, handling the infinite case. */
4810 range_predecessor (tree val)
4812 tree type = TREE_TYPE (val);
4814 if (INTEGRAL_TYPE_P (type)
4815 && operand_equal_p (val, TYPE_MIN_VALUE (type), 0))
4818 return range_binop (MINUS_EXPR, NULL_TREE, val, 0, integer_one_node, 0);
4821 /* Return the successor of VAL in its type, handling the infinite case. */
4824 range_successor (tree val)
4826 tree type = TREE_TYPE (val);
4828 if (INTEGRAL_TYPE_P (type)
4829 && operand_equal_p (val, TYPE_MAX_VALUE (type), 0))
4832 return range_binop (PLUS_EXPR, NULL_TREE, val, 0, integer_one_node, 0);
4835 /* Given two ranges, see if we can merge them into one. Return 1 if we
4836 can, 0 if we can't. Set the output range into the specified parameters. */
4839 merge_ranges (int *pin_p, tree *plow, tree *phigh, int in0_p, tree low0,
4840 tree high0, int in1_p, tree low1, tree high1)
4848 int lowequal = ((low0 == 0 && low1 == 0)
4849 || integer_onep (range_binop (EQ_EXPR, integer_type_node,
4850 low0, 0, low1, 0)));
4851 int highequal = ((high0 == 0 && high1 == 0)
4852 || integer_onep (range_binop (EQ_EXPR, integer_type_node,
4853 high0, 1, high1, 1)));
4855 /* Make range 0 be the range that starts first, or ends last if they
4856 start at the same value. Swap them if it isn't. */
4857 if (integer_onep (range_binop (GT_EXPR, integer_type_node,
4860 && integer_onep (range_binop (GT_EXPR, integer_type_node,
4861 high1, 1, high0, 1))))
4863 temp = in0_p, in0_p = in1_p, in1_p = temp;
4864 tem = low0, low0 = low1, low1 = tem;
4865 tem = high0, high0 = high1, high1 = tem;
4868 /* Now flag two cases, whether the ranges are disjoint or whether the
4869 second range is totally subsumed in the first. Note that the tests
4870 below are simplified by the ones above. */
4871 no_overlap = integer_onep (range_binop (LT_EXPR, integer_type_node,
4872 high0, 1, low1, 0));
4873 subset = integer_onep (range_binop (LE_EXPR, integer_type_node,
4874 high1, 1, high0, 1));
4876 /* We now have four cases, depending on whether we are including or
4877 excluding the two ranges. */
4880 /* If they don't overlap, the result is false. If the second range
4881 is a subset it is the result. Otherwise, the range is from the start
4882 of the second to the end of the first. */
4884 in_p = 0, low = high = 0;
4886 in_p = 1, low = low1, high = high1;
4888 in_p = 1, low = low1, high = high0;
4891 else if (in0_p && ! in1_p)
4893 /* If they don't overlap, the result is the first range. If they are
4894 equal, the result is false. If the second range is a subset of the
4895 first, and the ranges begin at the same place, we go from just after
4896 the end of the second range to the end of the first. If the second
4897 range is not a subset of the first, or if it is a subset and both
4898 ranges end at the same place, the range starts at the start of the
4899 first range and ends just before the second range.
4900 Otherwise, we can't describe this as a single range. */
4902 in_p = 1, low = low0, high = high0;
4903 else if (lowequal && highequal)
4904 in_p = 0, low = high = 0;
4905 else if (subset && lowequal)
4907 low = range_successor (high1);
4912 /* We are in the weird situation where high0 > high1 but
4913 high1 has no successor. Punt. */
4917 else if (! subset || highequal)
4920 high = range_predecessor (low1);
4924 /* low0 < low1 but low1 has no predecessor. Punt. */
4932 else if (! in0_p && in1_p)
4934 /* If they don't overlap, the result is the second range. If the second
4935 is a subset of the first, the result is false. Otherwise,
4936 the range starts just after the first range and ends at the
4937 end of the second. */
4939 in_p = 1, low = low1, high = high1;
4940 else if (subset || highequal)
4941 in_p = 0, low = high = 0;
4944 low = range_successor (high0);
4949 /* high1 > high0 but high0 has no successor. Punt. */
4957 /* The case where we are excluding both ranges. Here the complex case
4958 is if they don't overlap. In that case, the only time we have a
4959 range is if they are adjacent. If the second is a subset of the
4960 first, the result is the first. Otherwise, the range to exclude
4961 starts at the beginning of the first range and ends at the end of the
4965 if (integer_onep (range_binop (EQ_EXPR, integer_type_node,
4966 range_successor (high0),
4968 in_p = 0, low = low0, high = high1;
4971 /* Canonicalize - [min, x] into - [-, x]. */
4972 if (low0 && TREE_CODE (low0) == INTEGER_CST)
4973 switch (TREE_CODE (TREE_TYPE (low0)))
4976 if (TYPE_PRECISION (TREE_TYPE (low0))
4977 != GET_MODE_BITSIZE (TYPE_MODE (TREE_TYPE (low0))))
4981 if (tree_int_cst_equal (low0,
4982 TYPE_MIN_VALUE (TREE_TYPE (low0))))
4986 if (TYPE_UNSIGNED (TREE_TYPE (low0))
4987 && integer_zerop (low0))
4994 /* Canonicalize - [x, max] into - [x, -]. */
4995 if (high1 && TREE_CODE (high1) == INTEGER_CST)
4996 switch (TREE_CODE (TREE_TYPE (high1)))
4999 if (TYPE_PRECISION (TREE_TYPE (high1))
5000 != GET_MODE_BITSIZE (TYPE_MODE (TREE_TYPE (high1))))
5004 if (tree_int_cst_equal (high1,
5005 TYPE_MAX_VALUE (TREE_TYPE (high1))))
5009 if (TYPE_UNSIGNED (TREE_TYPE (high1))
5010 && integer_zerop (range_binop (PLUS_EXPR, NULL_TREE,
5012 integer_one_node, 1)))
5019 /* The ranges might be also adjacent between the maximum and
5020 minimum values of the given type. For
5021 - [{min,-}, x] and - [y, {max,-}] ranges where x + 1 < y
5022 return + [x + 1, y - 1]. */
5023 if (low0 == 0 && high1 == 0)
5025 low = range_successor (high0);
5026 high = range_predecessor (low1);
5027 if (low == 0 || high == 0)
5037 in_p = 0, low = low0, high = high0;
5039 in_p = 0, low = low0, high = high1;
5042 *pin_p = in_p, *plow = low, *phigh = high;
5047 /* Subroutine of fold, looking inside expressions of the form
5048 A op B ? A : C, where ARG0, ARG1 and ARG2 are the three operands
5049 of the COND_EXPR. This function is being used also to optimize
5050 A op B ? C : A, by reversing the comparison first.
5052 Return a folded expression whose code is not a COND_EXPR
5053 anymore, or NULL_TREE if no folding opportunity is found. */
5056 fold_cond_expr_with_comparison (tree type, tree arg0, tree arg1, tree arg2)
5058 enum tree_code comp_code = TREE_CODE (arg0);
5059 tree arg00 = TREE_OPERAND (arg0, 0);
5060 tree arg01 = TREE_OPERAND (arg0, 1);
5061 tree arg1_type = TREE_TYPE (arg1);
5067 /* If we have A op 0 ? A : -A, consider applying the following
5070 A == 0? A : -A same as -A
5071 A != 0? A : -A same as A
5072 A >= 0? A : -A same as abs (A)
5073 A > 0? A : -A same as abs (A)
5074 A <= 0? A : -A same as -abs (A)
5075 A < 0? A : -A same as -abs (A)
5077 None of these transformations work for modes with signed
5078 zeros. If A is +/-0, the first two transformations will
5079 change the sign of the result (from +0 to -0, or vice
5080 versa). The last four will fix the sign of the result,
5081 even though the original expressions could be positive or
5082 negative, depending on the sign of A.
5084 Note that all these transformations are correct if A is
5085 NaN, since the two alternatives (A and -A) are also NaNs. */
5086 if (!HONOR_SIGNED_ZEROS (TYPE_MODE (type))
5087 && (FLOAT_TYPE_P (TREE_TYPE (arg01))
5088 ? real_zerop (arg01)
5089 : integer_zerop (arg01))
5090 && ((TREE_CODE (arg2) == NEGATE_EXPR
5091 && operand_equal_p (TREE_OPERAND (arg2, 0), arg1, 0))
5092 /* In the case that A is of the form X-Y, '-A' (arg2) may
5093 have already been folded to Y-X, check for that. */
5094 || (TREE_CODE (arg1) == MINUS_EXPR
5095 && TREE_CODE (arg2) == MINUS_EXPR
5096 && operand_equal_p (TREE_OPERAND (arg1, 0),
5097 TREE_OPERAND (arg2, 1), 0)
5098 && operand_equal_p (TREE_OPERAND (arg1, 1),
5099 TREE_OPERAND (arg2, 0), 0))))
5104 tem = fold_convert (arg1_type, arg1);
5105 return pedantic_non_lvalue (fold_convert (type, negate_expr (tem)));
5108 return pedantic_non_lvalue (fold_convert (type, arg1));
5111 if (flag_trapping_math)
5116 if (TYPE_UNSIGNED (TREE_TYPE (arg1)))
5117 arg1 = fold_convert (signed_type_for
5118 (TREE_TYPE (arg1)), arg1);
5119 tem = fold_build1 (ABS_EXPR, TREE_TYPE (arg1), arg1);
5120 return pedantic_non_lvalue (fold_convert (type, tem));
5123 if (flag_trapping_math)
5127 if (TYPE_UNSIGNED (TREE_TYPE (arg1)))
5128 arg1 = fold_convert (signed_type_for
5129 (TREE_TYPE (arg1)), arg1);
5130 tem = fold_build1 (ABS_EXPR, TREE_TYPE (arg1), arg1);
5131 return negate_expr (fold_convert (type, tem));
5133 gcc_assert (TREE_CODE_CLASS (comp_code) == tcc_comparison);
5137 /* A != 0 ? A : 0 is simply A, unless A is -0. Likewise
5138 A == 0 ? A : 0 is always 0 unless A is -0. Note that
5139 both transformations are correct when A is NaN: A != 0
5140 is then true, and A == 0 is false. */
5142 if (!HONOR_SIGNED_ZEROS (TYPE_MODE (type))
5143 && integer_zerop (arg01) && integer_zerop (arg2))
5145 if (comp_code == NE_EXPR)
5146 return pedantic_non_lvalue (fold_convert (type, arg1));
5147 else if (comp_code == EQ_EXPR)
5148 return build_int_cst (type, 0);
5151 /* Try some transformations of A op B ? A : B.
5153 A == B? A : B same as B
5154 A != B? A : B same as A
5155 A >= B? A : B same as max (A, B)
5156 A > B? A : B same as max (B, A)
5157 A <= B? A : B same as min (A, B)
5158 A < B? A : B same as min (B, A)
5160 As above, these transformations don't work in the presence
5161 of signed zeros. For example, if A and B are zeros of
5162 opposite sign, the first two transformations will change
5163 the sign of the result. In the last four, the original
5164 expressions give different results for (A=+0, B=-0) and
5165 (A=-0, B=+0), but the transformed expressions do not.
5167 The first two transformations are correct if either A or B
5168 is a NaN. In the first transformation, the condition will
5169 be false, and B will indeed be chosen. In the case of the
5170 second transformation, the condition A != B will be true,
5171 and A will be chosen.
5173 The conversions to max() and min() are not correct if B is
5174 a number and A is not. The conditions in the original
5175 expressions will be false, so all four give B. The min()
5176 and max() versions would give a NaN instead. */
5177 if (!HONOR_SIGNED_ZEROS (TYPE_MODE (type))
5178 && operand_equal_for_comparison_p (arg01, arg2, arg00)
5179 /* Avoid these transformations if the COND_EXPR may be used
5180 as an lvalue in the C++ front-end. PR c++/19199. */
5182 || (strcmp (lang_hooks.name, "GNU C++") != 0
5183 && strcmp (lang_hooks.name, "GNU Objective-C++") != 0)
5184 || ! maybe_lvalue_p (arg1)
5185 || ! maybe_lvalue_p (arg2)))
5187 tree comp_op0 = arg00;
5188 tree comp_op1 = arg01;
5189 tree comp_type = TREE_TYPE (comp_op0);
5191 /* Avoid adding NOP_EXPRs in case this is an lvalue. */
5192 if (TYPE_MAIN_VARIANT (comp_type) == TYPE_MAIN_VARIANT (type))
5202 return pedantic_non_lvalue (fold_convert (type, arg2));
5204 return pedantic_non_lvalue (fold_convert (type, arg1));
5209 /* In C++ a ?: expression can be an lvalue, so put the
5210 operand which will be used if they are equal first
5211 so that we can convert this back to the
5212 corresponding COND_EXPR. */
5213 if (!HONOR_NANS (TYPE_MODE (TREE_TYPE (arg1))))
5215 comp_op0 = fold_convert (comp_type, comp_op0);
5216 comp_op1 = fold_convert (comp_type, comp_op1);
5217 tem = (comp_code == LE_EXPR || comp_code == UNLE_EXPR)
5218 ? fold_build2 (MIN_EXPR, comp_type, comp_op0, comp_op1)
5219 : fold_build2 (MIN_EXPR, comp_type, comp_op1, comp_op0);
5220 return pedantic_non_lvalue (fold_convert (type, tem));
5227 if (!HONOR_NANS (TYPE_MODE (TREE_TYPE (arg1))))
5229 comp_op0 = fold_convert (comp_type, comp_op0);
5230 comp_op1 = fold_convert (comp_type, comp_op1);
5231 tem = (comp_code == GE_EXPR || comp_code == UNGE_EXPR)
5232 ? fold_build2 (MAX_EXPR, comp_type, comp_op0, comp_op1)
5233 : fold_build2 (MAX_EXPR, comp_type, comp_op1, comp_op0);
5234 return pedantic_non_lvalue (fold_convert (type, tem));
5238 if (!HONOR_NANS (TYPE_MODE (TREE_TYPE (arg1))))
5239 return pedantic_non_lvalue (fold_convert (type, arg2));
5242 if (!HONOR_NANS (TYPE_MODE (TREE_TYPE (arg1))))
5243 return pedantic_non_lvalue (fold_convert (type, arg1));
5246 gcc_assert (TREE_CODE_CLASS (comp_code) == tcc_comparison);
5251 /* If this is A op C1 ? A : C2 with C1 and C2 constant integers,
5252 we might still be able to simplify this. For example,
5253 if C1 is one less or one more than C2, this might have started
5254 out as a MIN or MAX and been transformed by this function.
5255 Only good for INTEGER_TYPEs, because we need TYPE_MAX_VALUE. */
5257 if (INTEGRAL_TYPE_P (type)
5258 && TREE_CODE (arg01) == INTEGER_CST
5259 && TREE_CODE (arg2) == INTEGER_CST)
5263 /* We can replace A with C1 in this case. */
5264 arg1 = fold_convert (type, arg01);
5265 return fold_build3 (COND_EXPR, type, arg0, arg1, arg2);
5268 /* If C1 is C2 + 1, this is min(A, C2). */
5269 if (! operand_equal_p (arg2, TYPE_MAX_VALUE (type),
5271 && operand_equal_p (arg01,
5272 const_binop (PLUS_EXPR, arg2,
5273 build_int_cst (type, 1), 0),
5275 return pedantic_non_lvalue (fold_build2 (MIN_EXPR,
5277 fold_convert (type, arg1),
5282 /* If C1 is C2 - 1, this is min(A, C2). */
5283 if (! operand_equal_p (arg2, TYPE_MIN_VALUE (type),
5285 && operand_equal_p (arg01,
5286 const_binop (MINUS_EXPR, arg2,
5287 build_int_cst (type, 1), 0),
5289 return pedantic_non_lvalue (fold_build2 (MIN_EXPR,
5291 fold_convert (type, arg1),
5296 /* If C1 is C2 - 1, this is max(A, C2). */
5297 if (! operand_equal_p (arg2, TYPE_MIN_VALUE (type),
5299 && operand_equal_p (arg01,
5300 const_binop (MINUS_EXPR, arg2,
5301 build_int_cst (type, 1), 0),
5303 return pedantic_non_lvalue (fold_build2 (MAX_EXPR,
5305 fold_convert (type, arg1),
5310 /* If C1 is C2 + 1, this is max(A, C2). */
5311 if (! operand_equal_p (arg2, TYPE_MAX_VALUE (type),
5313 && operand_equal_p (arg01,
5314 const_binop (PLUS_EXPR, arg2,
5315 build_int_cst (type, 1), 0),
5317 return pedantic_non_lvalue (fold_build2 (MAX_EXPR,
5319 fold_convert (type, arg1),
5333 #ifndef LOGICAL_OP_NON_SHORT_CIRCUIT
5334 #define LOGICAL_OP_NON_SHORT_CIRCUIT \
5335 (BRANCH_COST (optimize_function_for_speed_p (cfun), \
5339 /* EXP is some logical combination of boolean tests. See if we can
5340 merge it into some range test. Return the new tree if so. */
5343 fold_range_test (enum tree_code code, tree type, tree op0, tree op1)
5345 int or_op = (code == TRUTH_ORIF_EXPR
5346 || code == TRUTH_OR_EXPR);
5347 int in0_p, in1_p, in_p;
5348 tree low0, low1, low, high0, high1, high;
5349 bool strict_overflow_p = false;
5350 tree lhs = make_range (op0, &in0_p, &low0, &high0, &strict_overflow_p);
5351 tree rhs = make_range (op1, &in1_p, &low1, &high1, &strict_overflow_p);
5353 const char * const warnmsg = G_("assuming signed overflow does not occur "
5354 "when simplifying range test");
5356 /* If this is an OR operation, invert both sides; we will invert
5357 again at the end. */
5359 in0_p = ! in0_p, in1_p = ! in1_p;
5361 /* If both expressions are the same, if we can merge the ranges, and we
5362 can build the range test, return it or it inverted. If one of the
5363 ranges is always true or always false, consider it to be the same
5364 expression as the other. */
5365 if ((lhs == 0 || rhs == 0 || operand_equal_p (lhs, rhs, 0))
5366 && merge_ranges (&in_p, &low, &high, in0_p, low0, high0,
5368 && 0 != (tem = (build_range_check (type,
5370 : rhs != 0 ? rhs : integer_zero_node,
5373 if (strict_overflow_p)
5374 fold_overflow_warning (warnmsg, WARN_STRICT_OVERFLOW_COMPARISON);
5375 return or_op ? invert_truthvalue (tem) : tem;
5378 /* On machines where the branch cost is expensive, if this is a
5379 short-circuited branch and the underlying object on both sides
5380 is the same, make a non-short-circuit operation. */
5381 else if (LOGICAL_OP_NON_SHORT_CIRCUIT
5382 && lhs != 0 && rhs != 0
5383 && (code == TRUTH_ANDIF_EXPR
5384 || code == TRUTH_ORIF_EXPR)
5385 && operand_equal_p (lhs, rhs, 0))
5387 /* If simple enough, just rewrite. Otherwise, make a SAVE_EXPR
5388 unless we are at top level or LHS contains a PLACEHOLDER_EXPR, in
5389 which cases we can't do this. */
5390 if (simple_operand_p (lhs))
5391 return build2 (code == TRUTH_ANDIF_EXPR
5392 ? TRUTH_AND_EXPR : TRUTH_OR_EXPR,
5395 else if (lang_hooks.decls.global_bindings_p () == 0
5396 && ! CONTAINS_PLACEHOLDER_P (lhs))
5398 tree common = save_expr (lhs);
5400 if (0 != (lhs = build_range_check (type, common,
5401 or_op ? ! in0_p : in0_p,
5403 && (0 != (rhs = build_range_check (type, common,
5404 or_op ? ! in1_p : in1_p,
5407 if (strict_overflow_p)
5408 fold_overflow_warning (warnmsg,
5409 WARN_STRICT_OVERFLOW_COMPARISON);
5410 return build2 (code == TRUTH_ANDIF_EXPR
5411 ? TRUTH_AND_EXPR : TRUTH_OR_EXPR,
5420 /* Subroutine for fold_truthop: C is an INTEGER_CST interpreted as a P
5421 bit value. Arrange things so the extra bits will be set to zero if and
5422 only if C is signed-extended to its full width. If MASK is nonzero,
5423 it is an INTEGER_CST that should be AND'ed with the extra bits. */
5426 unextend (tree c, int p, int unsignedp, tree mask)
5428 tree type = TREE_TYPE (c);
5429 int modesize = GET_MODE_BITSIZE (TYPE_MODE (type));
5432 if (p == modesize || unsignedp)
5435 /* We work by getting just the sign bit into the low-order bit, then
5436 into the high-order bit, then sign-extend. We then XOR that value
5438 temp = const_binop (RSHIFT_EXPR, c, size_int (p - 1), 0);
5439 temp = const_binop (BIT_AND_EXPR, temp, size_int (1), 0);
5441 /* We must use a signed type in order to get an arithmetic right shift.
5442 However, we must also avoid introducing accidental overflows, so that
5443 a subsequent call to integer_zerop will work. Hence we must
5444 do the type conversion here. At this point, the constant is either
5445 zero or one, and the conversion to a signed type can never overflow.
5446 We could get an overflow if this conversion is done anywhere else. */
5447 if (TYPE_UNSIGNED (type))
5448 temp = fold_convert (signed_type_for (type), temp);
5450 temp = const_binop (LSHIFT_EXPR, temp, size_int (modesize - 1), 0);
5451 temp = const_binop (RSHIFT_EXPR, temp, size_int (modesize - p - 1), 0);
5453 temp = const_binop (BIT_AND_EXPR, temp,
5454 fold_convert (TREE_TYPE (c), mask), 0);
5455 /* If necessary, convert the type back to match the type of C. */
5456 if (TYPE_UNSIGNED (type))
5457 temp = fold_convert (type, temp);
5459 return fold_convert (type, const_binop (BIT_XOR_EXPR, c, temp, 0));
5462 /* Find ways of folding logical expressions of LHS and RHS:
5463 Try to merge two comparisons to the same innermost item.
5464 Look for range tests like "ch >= '0' && ch <= '9'".
5465 Look for combinations of simple terms on machines with expensive branches
5466 and evaluate the RHS unconditionally.
5468 For example, if we have p->a == 2 && p->b == 4 and we can make an
5469 object large enough to span both A and B, we can do this with a comparison
5470 against the object ANDed with the a mask.
5472 If we have p->a == q->a && p->b == q->b, we may be able to use bit masking
5473 operations to do this with one comparison.
5475 We check for both normal comparisons and the BIT_AND_EXPRs made this by
5476 function and the one above.
5478 CODE is the logical operation being done. It can be TRUTH_ANDIF_EXPR,
5479 TRUTH_AND_EXPR, TRUTH_ORIF_EXPR, or TRUTH_OR_EXPR.
5481 TRUTH_TYPE is the type of the logical operand and LHS and RHS are its
5484 We return the simplified tree or 0 if no optimization is possible. */
5487 fold_truthop (enum tree_code code, tree truth_type, tree lhs, tree rhs)
5489 /* If this is the "or" of two comparisons, we can do something if
5490 the comparisons are NE_EXPR. If this is the "and", we can do something
5491 if the comparisons are EQ_EXPR. I.e.,
5492 (a->b == 2 && a->c == 4) can become (a->new == NEW).
5494 WANTED_CODE is this operation code. For single bit fields, we can
5495 convert EQ_EXPR to NE_EXPR so we need not reject the "wrong"
5496 comparison for one-bit fields. */
5498 enum tree_code wanted_code;
5499 enum tree_code lcode, rcode;
5500 tree ll_arg, lr_arg, rl_arg, rr_arg;
5501 tree ll_inner, lr_inner, rl_inner, rr_inner;
5502 HOST_WIDE_INT ll_bitsize, ll_bitpos, lr_bitsize, lr_bitpos;
5503 HOST_WIDE_INT rl_bitsize, rl_bitpos, rr_bitsize, rr_bitpos;
5504 HOST_WIDE_INT xll_bitpos, xlr_bitpos, xrl_bitpos, xrr_bitpos;
5505 HOST_WIDE_INT lnbitsize, lnbitpos, rnbitsize, rnbitpos;
5506 int ll_unsignedp, lr_unsignedp, rl_unsignedp, rr_unsignedp;
5507 enum machine_mode ll_mode, lr_mode, rl_mode, rr_mode;
5508 enum machine_mode lnmode, rnmode;
5509 tree ll_mask, lr_mask, rl_mask, rr_mask;
5510 tree ll_and_mask, lr_and_mask, rl_and_mask, rr_and_mask;
5511 tree l_const, r_const;
5512 tree lntype, rntype, result;
5513 HOST_WIDE_INT first_bit, end_bit;
5515 tree orig_lhs = lhs, orig_rhs = rhs;
5516 enum tree_code orig_code = code;
5518 /* Start by getting the comparison codes. Fail if anything is volatile.
5519 If one operand is a BIT_AND_EXPR with the constant one, treat it as if
5520 it were surrounded with a NE_EXPR. */
5522 if (TREE_SIDE_EFFECTS (lhs) || TREE_SIDE_EFFECTS (rhs))
5525 lcode = TREE_CODE (lhs);
5526 rcode = TREE_CODE (rhs);
5528 if (lcode == BIT_AND_EXPR && integer_onep (TREE_OPERAND (lhs, 1)))
5530 lhs = build2 (NE_EXPR, truth_type, lhs,
5531 build_int_cst (TREE_TYPE (lhs), 0));
5535 if (rcode == BIT_AND_EXPR && integer_onep (TREE_OPERAND (rhs, 1)))
5537 rhs = build2 (NE_EXPR, truth_type, rhs,
5538 build_int_cst (TREE_TYPE (rhs), 0));
5542 if (TREE_CODE_CLASS (lcode) != tcc_comparison
5543 || TREE_CODE_CLASS (rcode) != tcc_comparison)
5546 ll_arg = TREE_OPERAND (lhs, 0);
5547 lr_arg = TREE_OPERAND (lhs, 1);
5548 rl_arg = TREE_OPERAND (rhs, 0);
5549 rr_arg = TREE_OPERAND (rhs, 1);
5551 /* Simplify (x<y) && (x==y) into (x<=y) and related optimizations. */
5552 if (simple_operand_p (ll_arg)
5553 && simple_operand_p (lr_arg))
5556 if (operand_equal_p (ll_arg, rl_arg, 0)
5557 && operand_equal_p (lr_arg, rr_arg, 0))
5559 result = combine_comparisons (code, lcode, rcode,
5560 truth_type, ll_arg, lr_arg);
5564 else if (operand_equal_p (ll_arg, rr_arg, 0)
5565 && operand_equal_p (lr_arg, rl_arg, 0))
5567 result = combine_comparisons (code, lcode,
5568 swap_tree_comparison (rcode),
5569 truth_type, ll_arg, lr_arg);
5575 code = ((code == TRUTH_AND_EXPR || code == TRUTH_ANDIF_EXPR)
5576 ? TRUTH_AND_EXPR : TRUTH_OR_EXPR);
5578 /* If the RHS can be evaluated unconditionally and its operands are
5579 simple, it wins to evaluate the RHS unconditionally on machines
5580 with expensive branches. In this case, this isn't a comparison
5581 that can be merged. Avoid doing this if the RHS is a floating-point
5582 comparison since those can trap. */
5584 if (BRANCH_COST (optimize_function_for_speed_p (cfun),
5586 && ! FLOAT_TYPE_P (TREE_TYPE (rl_arg))
5587 && simple_operand_p (rl_arg)
5588 && simple_operand_p (rr_arg))
5590 /* Convert (a != 0) || (b != 0) into (a | b) != 0. */
5591 if (code == TRUTH_OR_EXPR
5592 && lcode == NE_EXPR && integer_zerop (lr_arg)
5593 && rcode == NE_EXPR && integer_zerop (rr_arg)
5594 && TREE_TYPE (ll_arg) == TREE_TYPE (rl_arg)
5595 && INTEGRAL_TYPE_P (TREE_TYPE (ll_arg)))
5596 return build2 (NE_EXPR, truth_type,
5597 build2 (BIT_IOR_EXPR, TREE_TYPE (ll_arg),
5599 build_int_cst (TREE_TYPE (ll_arg), 0));
5601 /* Convert (a == 0) && (b == 0) into (a | b) == 0. */
5602 if (code == TRUTH_AND_EXPR
5603 && lcode == EQ_EXPR && integer_zerop (lr_arg)
5604 && rcode == EQ_EXPR && integer_zerop (rr_arg)
5605 && TREE_TYPE (ll_arg) == TREE_TYPE (rl_arg)
5606 && INTEGRAL_TYPE_P (TREE_TYPE (ll_arg)))
5607 return build2 (EQ_EXPR, truth_type,
5608 build2 (BIT_IOR_EXPR, TREE_TYPE (ll_arg),
5610 build_int_cst (TREE_TYPE (ll_arg), 0));
5612 if (LOGICAL_OP_NON_SHORT_CIRCUIT)
5614 if (code != orig_code || lhs != orig_lhs || rhs != orig_rhs)
5615 return build2 (code, truth_type, lhs, rhs);
5620 /* See if the comparisons can be merged. Then get all the parameters for
5623 if ((lcode != EQ_EXPR && lcode != NE_EXPR)
5624 || (rcode != EQ_EXPR && rcode != NE_EXPR))
5628 ll_inner = decode_field_reference (ll_arg,
5629 &ll_bitsize, &ll_bitpos, &ll_mode,
5630 &ll_unsignedp, &volatilep, &ll_mask,
5632 lr_inner = decode_field_reference (lr_arg,
5633 &lr_bitsize, &lr_bitpos, &lr_mode,
5634 &lr_unsignedp, &volatilep, &lr_mask,
5636 rl_inner = decode_field_reference (rl_arg,
5637 &rl_bitsize, &rl_bitpos, &rl_mode,
5638 &rl_unsignedp, &volatilep, &rl_mask,
5640 rr_inner = decode_field_reference (rr_arg,
5641 &rr_bitsize, &rr_bitpos, &rr_mode,
5642 &rr_unsignedp, &volatilep, &rr_mask,
5645 /* It must be true that the inner operation on the lhs of each
5646 comparison must be the same if we are to be able to do anything.
5647 Then see if we have constants. If not, the same must be true for
5649 if (volatilep || ll_inner == 0 || rl_inner == 0
5650 || ! operand_equal_p (ll_inner, rl_inner, 0))
5653 if (TREE_CODE (lr_arg) == INTEGER_CST
5654 && TREE_CODE (rr_arg) == INTEGER_CST)
5655 l_const = lr_arg, r_const = rr_arg;
5656 else if (lr_inner == 0 || rr_inner == 0
5657 || ! operand_equal_p (lr_inner, rr_inner, 0))
5660 l_const = r_const = 0;
5662 /* If either comparison code is not correct for our logical operation,
5663 fail. However, we can convert a one-bit comparison against zero into
5664 the opposite comparison against that bit being set in the field. */
5666 wanted_code = (code == TRUTH_AND_EXPR ? EQ_EXPR : NE_EXPR);
5667 if (lcode != wanted_code)
5669 if (l_const && integer_zerop (l_const) && integer_pow2p (ll_mask))
5671 /* Make the left operand unsigned, since we are only interested
5672 in the value of one bit. Otherwise we are doing the wrong
5681 /* This is analogous to the code for l_const above. */
5682 if (rcode != wanted_code)
5684 if (r_const && integer_zerop (r_const) && integer_pow2p (rl_mask))
5693 /* See if we can find a mode that contains both fields being compared on
5694 the left. If we can't, fail. Otherwise, update all constants and masks
5695 to be relative to a field of that size. */
5696 first_bit = MIN (ll_bitpos, rl_bitpos);
5697 end_bit = MAX (ll_bitpos + ll_bitsize, rl_bitpos + rl_bitsize);
5698 lnmode = get_best_mode (end_bit - first_bit, first_bit,
5699 TYPE_ALIGN (TREE_TYPE (ll_inner)), word_mode,
5701 if (lnmode == VOIDmode)
5704 lnbitsize = GET_MODE_BITSIZE (lnmode);
5705 lnbitpos = first_bit & ~ (lnbitsize - 1);
5706 lntype = lang_hooks.types.type_for_size (lnbitsize, 1);
5707 xll_bitpos = ll_bitpos - lnbitpos, xrl_bitpos = rl_bitpos - lnbitpos;
5709 if (BYTES_BIG_ENDIAN)
5711 xll_bitpos = lnbitsize - xll_bitpos - ll_bitsize;
5712 xrl_bitpos = lnbitsize - xrl_bitpos - rl_bitsize;
5715 ll_mask = const_binop (LSHIFT_EXPR, fold_convert (lntype, ll_mask),
5716 size_int (xll_bitpos), 0);
5717 rl_mask = const_binop (LSHIFT_EXPR, fold_convert (lntype, rl_mask),
5718 size_int (xrl_bitpos), 0);
5722 l_const = fold_convert (lntype, l_const);
5723 l_const = unextend (l_const, ll_bitsize, ll_unsignedp, ll_and_mask);
5724 l_const = const_binop (LSHIFT_EXPR, l_const, size_int (xll_bitpos), 0);
5725 if (! integer_zerop (const_binop (BIT_AND_EXPR, l_const,
5726 fold_build1 (BIT_NOT_EXPR,
5730 warning (0, "comparison is always %d", wanted_code == NE_EXPR);
5732 return constant_boolean_node (wanted_code == NE_EXPR, truth_type);
5737 r_const = fold_convert (lntype, r_const);
5738 r_const = unextend (r_const, rl_bitsize, rl_unsignedp, rl_and_mask);
5739 r_const = const_binop (LSHIFT_EXPR, r_const, size_int (xrl_bitpos), 0);
5740 if (! integer_zerop (const_binop (BIT_AND_EXPR, r_const,
5741 fold_build1 (BIT_NOT_EXPR,
5745 warning (0, "comparison is always %d", wanted_code == NE_EXPR);
5747 return constant_boolean_node (wanted_code == NE_EXPR, truth_type);
5751 /* If the right sides are not constant, do the same for it. Also,
5752 disallow this optimization if a size or signedness mismatch occurs
5753 between the left and right sides. */
5756 if (ll_bitsize != lr_bitsize || rl_bitsize != rr_bitsize
5757 || ll_unsignedp != lr_unsignedp || rl_unsignedp != rr_unsignedp
5758 /* Make sure the two fields on the right
5759 correspond to the left without being swapped. */
5760 || ll_bitpos - rl_bitpos != lr_bitpos - rr_bitpos)
5763 first_bit = MIN (lr_bitpos, rr_bitpos);
5764 end_bit = MAX (lr_bitpos + lr_bitsize, rr_bitpos + rr_bitsize);
5765 rnmode = get_best_mode (end_bit - first_bit, first_bit,
5766 TYPE_ALIGN (TREE_TYPE (lr_inner)), word_mode,
5768 if (rnmode == VOIDmode)
5771 rnbitsize = GET_MODE_BITSIZE (rnmode);
5772 rnbitpos = first_bit & ~ (rnbitsize - 1);
5773 rntype = lang_hooks.types.type_for_size (rnbitsize, 1);
5774 xlr_bitpos = lr_bitpos - rnbitpos, xrr_bitpos = rr_bitpos - rnbitpos;
5776 if (BYTES_BIG_ENDIAN)
5778 xlr_bitpos = rnbitsize - xlr_bitpos - lr_bitsize;
5779 xrr_bitpos = rnbitsize - xrr_bitpos - rr_bitsize;
5782 lr_mask = const_binop (LSHIFT_EXPR, fold_convert (rntype, lr_mask),
5783 size_int (xlr_bitpos), 0);
5784 rr_mask = const_binop (LSHIFT_EXPR, fold_convert (rntype, rr_mask),
5785 size_int (xrr_bitpos), 0);
5787 /* Make a mask that corresponds to both fields being compared.
5788 Do this for both items being compared. If the operands are the
5789 same size and the bits being compared are in the same position
5790 then we can do this by masking both and comparing the masked
5792 ll_mask = const_binop (BIT_IOR_EXPR, ll_mask, rl_mask, 0);
5793 lr_mask = const_binop (BIT_IOR_EXPR, lr_mask, rr_mask, 0);
5794 if (lnbitsize == rnbitsize && xll_bitpos == xlr_bitpos)
5796 lhs = make_bit_field_ref (ll_inner, lntype, lnbitsize, lnbitpos,
5797 ll_unsignedp || rl_unsignedp);
5798 if (! all_ones_mask_p (ll_mask, lnbitsize))
5799 lhs = build2 (BIT_AND_EXPR, lntype, lhs, ll_mask);
5801 rhs = make_bit_field_ref (lr_inner, rntype, rnbitsize, rnbitpos,
5802 lr_unsignedp || rr_unsignedp);
5803 if (! all_ones_mask_p (lr_mask, rnbitsize))
5804 rhs = build2 (BIT_AND_EXPR, rntype, rhs, lr_mask);
5806 return build2 (wanted_code, truth_type, lhs, rhs);
5809 /* There is still another way we can do something: If both pairs of
5810 fields being compared are adjacent, we may be able to make a wider
5811 field containing them both.
5813 Note that we still must mask the lhs/rhs expressions. Furthermore,
5814 the mask must be shifted to account for the shift done by
5815 make_bit_field_ref. */
5816 if ((ll_bitsize + ll_bitpos == rl_bitpos
5817 && lr_bitsize + lr_bitpos == rr_bitpos)
5818 || (ll_bitpos == rl_bitpos + rl_bitsize
5819 && lr_bitpos == rr_bitpos + rr_bitsize))
5823 lhs = make_bit_field_ref (ll_inner, lntype, ll_bitsize + rl_bitsize,
5824 MIN (ll_bitpos, rl_bitpos), ll_unsignedp);
5825 rhs = make_bit_field_ref (lr_inner, rntype, lr_bitsize + rr_bitsize,
5826 MIN (lr_bitpos, rr_bitpos), lr_unsignedp);
5828 ll_mask = const_binop (RSHIFT_EXPR, ll_mask,
5829 size_int (MIN (xll_bitpos, xrl_bitpos)), 0);
5830 lr_mask = const_binop (RSHIFT_EXPR, lr_mask,
5831 size_int (MIN (xlr_bitpos, xrr_bitpos)), 0);
5833 /* Convert to the smaller type before masking out unwanted bits. */
5835 if (lntype != rntype)
5837 if (lnbitsize > rnbitsize)
5839 lhs = fold_convert (rntype, lhs);
5840 ll_mask = fold_convert (rntype, ll_mask);
5843 else if (lnbitsize < rnbitsize)
5845 rhs = fold_convert (lntype, rhs);
5846 lr_mask = fold_convert (lntype, lr_mask);
5851 if (! all_ones_mask_p (ll_mask, ll_bitsize + rl_bitsize))
5852 lhs = build2 (BIT_AND_EXPR, type, lhs, ll_mask);
5854 if (! all_ones_mask_p (lr_mask, lr_bitsize + rr_bitsize))
5855 rhs = build2 (BIT_AND_EXPR, type, rhs, lr_mask);
5857 return build2 (wanted_code, truth_type, lhs, rhs);
5863 /* Handle the case of comparisons with constants. If there is something in
5864 common between the masks, those bits of the constants must be the same.
5865 If not, the condition is always false. Test for this to avoid generating
5866 incorrect code below. */
5867 result = const_binop (BIT_AND_EXPR, ll_mask, rl_mask, 0);
5868 if (! integer_zerop (result)
5869 && simple_cst_equal (const_binop (BIT_AND_EXPR, result, l_const, 0),
5870 const_binop (BIT_AND_EXPR, result, r_const, 0)) != 1)
5872 if (wanted_code == NE_EXPR)
5874 warning (0, "%<or%> of unmatched not-equal tests is always 1");
5875 return constant_boolean_node (true, truth_type);
5879 warning (0, "%<and%> of mutually exclusive equal-tests is always 0");
5880 return constant_boolean_node (false, truth_type);
5884 /* Construct the expression we will return. First get the component
5885 reference we will make. Unless the mask is all ones the width of
5886 that field, perform the mask operation. Then compare with the
5888 result = make_bit_field_ref (ll_inner, lntype, lnbitsize, lnbitpos,
5889 ll_unsignedp || rl_unsignedp);
5891 ll_mask = const_binop (BIT_IOR_EXPR, ll_mask, rl_mask, 0);
5892 if (! all_ones_mask_p (ll_mask, lnbitsize))
5893 result = build2 (BIT_AND_EXPR, lntype, result, ll_mask);
5895 return build2 (wanted_code, truth_type, result,
5896 const_binop (BIT_IOR_EXPR, l_const, r_const, 0));
5899 /* Optimize T, which is a comparison of a MIN_EXPR or MAX_EXPR with a
5903 optimize_minmax_comparison (enum tree_code code, tree type, tree op0, tree op1)
5906 enum tree_code op_code;
5909 int consts_equal, consts_lt;
5912 STRIP_SIGN_NOPS (arg0);
5914 op_code = TREE_CODE (arg0);
5915 minmax_const = TREE_OPERAND (arg0, 1);
5916 comp_const = fold_convert (TREE_TYPE (arg0), op1);
5917 consts_equal = tree_int_cst_equal (minmax_const, comp_const);
5918 consts_lt = tree_int_cst_lt (minmax_const, comp_const);
5919 inner = TREE_OPERAND (arg0, 0);
5921 /* If something does not permit us to optimize, return the original tree. */
5922 if ((op_code != MIN_EXPR && op_code != MAX_EXPR)
5923 || TREE_CODE (comp_const) != INTEGER_CST
5924 || TREE_OVERFLOW (comp_const)
5925 || TREE_CODE (minmax_const) != INTEGER_CST
5926 || TREE_OVERFLOW (minmax_const))
5929 /* Now handle all the various comparison codes. We only handle EQ_EXPR
5930 and GT_EXPR, doing the rest with recursive calls using logical
5934 case NE_EXPR: case LT_EXPR: case LE_EXPR:
5936 tree tem = optimize_minmax_comparison (invert_tree_comparison (code, false),
5939 return invert_truthvalue (tem);
5945 fold_build2 (TRUTH_ORIF_EXPR, type,
5946 optimize_minmax_comparison
5947 (EQ_EXPR, type, arg0, comp_const),
5948 optimize_minmax_comparison
5949 (GT_EXPR, type, arg0, comp_const));
5952 if (op_code == MAX_EXPR && consts_equal)
5953 /* MAX (X, 0) == 0 -> X <= 0 */
5954 return fold_build2 (LE_EXPR, type, inner, comp_const);
5956 else if (op_code == MAX_EXPR && consts_lt)
5957 /* MAX (X, 0) == 5 -> X == 5 */
5958 return fold_build2 (EQ_EXPR, type, inner, comp_const);
5960 else if (op_code == MAX_EXPR)
5961 /* MAX (X, 0) == -1 -> false */
5962 return omit_one_operand (type, integer_zero_node, inner);
5964 else if (consts_equal)
5965 /* MIN (X, 0) == 0 -> X >= 0 */
5966 return fold_build2 (GE_EXPR, type, inner, comp_const);
5969 /* MIN (X, 0) == 5 -> false */
5970 return omit_one_operand (type, integer_zero_node, inner);
5973 /* MIN (X, 0) == -1 -> X == -1 */
5974 return fold_build2 (EQ_EXPR, type, inner, comp_const);
5977 if (op_code == MAX_EXPR && (consts_equal || consts_lt))
5978 /* MAX (X, 0) > 0 -> X > 0
5979 MAX (X, 0) > 5 -> X > 5 */
5980 return fold_build2 (GT_EXPR, type, inner, comp_const);
5982 else if (op_code == MAX_EXPR)
5983 /* MAX (X, 0) > -1 -> true */
5984 return omit_one_operand (type, integer_one_node, inner);
5986 else if (op_code == MIN_EXPR && (consts_equal || consts_lt))
5987 /* MIN (X, 0) > 0 -> false
5988 MIN (X, 0) > 5 -> false */
5989 return omit_one_operand (type, integer_zero_node, inner);
5992 /* MIN (X, 0) > -1 -> X > -1 */
5993 return fold_build2 (GT_EXPR, type, inner, comp_const);
6000 /* T is an integer expression that is being multiplied, divided, or taken a
6001 modulus (CODE says which and what kind of divide or modulus) by a
6002 constant C. See if we can eliminate that operation by folding it with
6003 other operations already in T. WIDE_TYPE, if non-null, is a type that
6004 should be used for the computation if wider than our type.
6006 For example, if we are dividing (X * 8) + (Y * 16) by 4, we can return
6007 (X * 2) + (Y * 4). We must, however, be assured that either the original
6008 expression would not overflow or that overflow is undefined for the type
6009 in the language in question.
6011 If we return a non-null expression, it is an equivalent form of the
6012 original computation, but need not be in the original type.
6014 We set *STRICT_OVERFLOW_P to true if the return values depends on
6015 signed overflow being undefined. Otherwise we do not change
6016 *STRICT_OVERFLOW_P. */
6019 extract_muldiv (tree t, tree c, enum tree_code code, tree wide_type,
6020 bool *strict_overflow_p)
6022 /* To avoid exponential search depth, refuse to allow recursion past
6023 three levels. Beyond that (1) it's highly unlikely that we'll find
6024 something interesting and (2) we've probably processed it before
6025 when we built the inner expression. */
6034 ret = extract_muldiv_1 (t, c, code, wide_type, strict_overflow_p);
6041 extract_muldiv_1 (tree t, tree c, enum tree_code code, tree wide_type,
6042 bool *strict_overflow_p)
6044 tree type = TREE_TYPE (t);
6045 enum tree_code tcode = TREE_CODE (t);
6046 tree ctype = (wide_type != 0 && (GET_MODE_SIZE (TYPE_MODE (wide_type))
6047 > GET_MODE_SIZE (TYPE_MODE (type)))
6048 ? wide_type : type);
6050 int same_p = tcode == code;
6051 tree op0 = NULL_TREE, op1 = NULL_TREE;
6052 bool sub_strict_overflow_p;
6054 /* Don't deal with constants of zero here; they confuse the code below. */
6055 if (integer_zerop (c))
6058 if (TREE_CODE_CLASS (tcode) == tcc_unary)
6059 op0 = TREE_OPERAND (t, 0);
6061 if (TREE_CODE_CLASS (tcode) == tcc_binary)
6062 op0 = TREE_OPERAND (t, 0), op1 = TREE_OPERAND (t, 1);
6064 /* Note that we need not handle conditional operations here since fold
6065 already handles those cases. So just do arithmetic here. */
6069 /* For a constant, we can always simplify if we are a multiply
6070 or (for divide and modulus) if it is a multiple of our constant. */
6071 if (code == MULT_EXPR
6072 || integer_zerop (const_binop (TRUNC_MOD_EXPR, t, c, 0)))
6073 return const_binop (code, fold_convert (ctype, t),
6074 fold_convert (ctype, c), 0);
6077 CASE_CONVERT: case NON_LVALUE_EXPR:
6078 /* If op0 is an expression ... */
6079 if ((COMPARISON_CLASS_P (op0)
6080 || UNARY_CLASS_P (op0)
6081 || BINARY_CLASS_P (op0)
6082 || VL_EXP_CLASS_P (op0)
6083 || EXPRESSION_CLASS_P (op0))
6084 /* ... and has wrapping overflow, and its type is smaller
6085 than ctype, then we cannot pass through as widening. */
6086 && ((TYPE_OVERFLOW_WRAPS (TREE_TYPE (op0))
6087 && ! (TREE_CODE (TREE_TYPE (op0)) == INTEGER_TYPE
6088 && TYPE_IS_SIZETYPE (TREE_TYPE (op0)))
6089 && (TYPE_PRECISION (ctype)
6090 > TYPE_PRECISION (TREE_TYPE (op0))))
6091 /* ... or this is a truncation (t is narrower than op0),
6092 then we cannot pass through this narrowing. */
6093 || (TYPE_PRECISION (type)
6094 < TYPE_PRECISION (TREE_TYPE (op0)))
6095 /* ... or signedness changes for division or modulus,
6096 then we cannot pass through this conversion. */
6097 || (code != MULT_EXPR
6098 && (TYPE_UNSIGNED (ctype)
6099 != TYPE_UNSIGNED (TREE_TYPE (op0))))
6100 /* ... or has undefined overflow while the converted to
6101 type has not, we cannot do the operation in the inner type
6102 as that would introduce undefined overflow. */
6103 || (TYPE_OVERFLOW_UNDEFINED (TREE_TYPE (op0))
6104 && !TYPE_OVERFLOW_UNDEFINED (type))))
6107 /* Pass the constant down and see if we can make a simplification. If
6108 we can, replace this expression with the inner simplification for
6109 possible later conversion to our or some other type. */
6110 if ((t2 = fold_convert (TREE_TYPE (op0), c)) != 0
6111 && TREE_CODE (t2) == INTEGER_CST
6112 && !TREE_OVERFLOW (t2)
6113 && (0 != (t1 = extract_muldiv (op0, t2, code,
6115 ? ctype : NULL_TREE,
6116 strict_overflow_p))))
6121 /* If widening the type changes it from signed to unsigned, then we
6122 must avoid building ABS_EXPR itself as unsigned. */
6123 if (TYPE_UNSIGNED (ctype) && !TYPE_UNSIGNED (type))
6125 tree cstype = (*signed_type_for) (ctype);
6126 if ((t1 = extract_muldiv (op0, c, code, cstype, strict_overflow_p))
6129 t1 = fold_build1 (tcode, cstype, fold_convert (cstype, t1));
6130 return fold_convert (ctype, t1);
6134 /* If the constant is negative, we cannot simplify this. */
6135 if (tree_int_cst_sgn (c) == -1)
6139 if ((t1 = extract_muldiv (op0, c, code, wide_type, strict_overflow_p))
6141 return fold_build1 (tcode, ctype, fold_convert (ctype, t1));
6144 case MIN_EXPR: case MAX_EXPR:
6145 /* If widening the type changes the signedness, then we can't perform
6146 this optimization as that changes the result. */
6147 if (TYPE_UNSIGNED (ctype) != TYPE_UNSIGNED (type))
6150 /* MIN (a, b) / 5 -> MIN (a / 5, b / 5) */
6151 sub_strict_overflow_p = false;
6152 if ((t1 = extract_muldiv (op0, c, code, wide_type,
6153 &sub_strict_overflow_p)) != 0
6154 && (t2 = extract_muldiv (op1, c, code, wide_type,
6155 &sub_strict_overflow_p)) != 0)
6157 if (tree_int_cst_sgn (c) < 0)
6158 tcode = (tcode == MIN_EXPR ? MAX_EXPR : MIN_EXPR);
6159 if (sub_strict_overflow_p)
6160 *strict_overflow_p = true;
6161 return fold_build2 (tcode, ctype, fold_convert (ctype, t1),
6162 fold_convert (ctype, t2));
6166 case LSHIFT_EXPR: case RSHIFT_EXPR:
6167 /* If the second operand is constant, this is a multiplication
6168 or floor division, by a power of two, so we can treat it that
6169 way unless the multiplier or divisor overflows. Signed
6170 left-shift overflow is implementation-defined rather than
6171 undefined in C90, so do not convert signed left shift into
6173 if (TREE_CODE (op1) == INTEGER_CST
6174 && (tcode == RSHIFT_EXPR || TYPE_UNSIGNED (TREE_TYPE (op0)))
6175 /* const_binop may not detect overflow correctly,
6176 so check for it explicitly here. */
6177 && TYPE_PRECISION (TREE_TYPE (size_one_node)) > TREE_INT_CST_LOW (op1)
6178 && TREE_INT_CST_HIGH (op1) == 0
6179 && 0 != (t1 = fold_convert (ctype,
6180 const_binop (LSHIFT_EXPR,
6183 && !TREE_OVERFLOW (t1))
6184 return extract_muldiv (build2 (tcode == LSHIFT_EXPR
6185 ? MULT_EXPR : FLOOR_DIV_EXPR,
6186 ctype, fold_convert (ctype, op0), t1),
6187 c, code, wide_type, strict_overflow_p);
6190 case PLUS_EXPR: case MINUS_EXPR:
6191 /* See if we can eliminate the operation on both sides. If we can, we
6192 can return a new PLUS or MINUS. If we can't, the only remaining
6193 cases where we can do anything are if the second operand is a
6195 sub_strict_overflow_p = false;
6196 t1 = extract_muldiv (op0, c, code, wide_type, &sub_strict_overflow_p);
6197 t2 = extract_muldiv (op1, c, code, wide_type, &sub_strict_overflow_p);
6198 if (t1 != 0 && t2 != 0
6199 && (code == MULT_EXPR
6200 /* If not multiplication, we can only do this if both operands
6201 are divisible by c. */
6202 || (multiple_of_p (ctype, op0, c)
6203 && multiple_of_p (ctype, op1, c))))
6205 if (sub_strict_overflow_p)
6206 *strict_overflow_p = true;
6207 return fold_build2 (tcode, ctype, fold_convert (ctype, t1),
6208 fold_convert (ctype, t2));
6211 /* If this was a subtraction, negate OP1 and set it to be an addition.
6212 This simplifies the logic below. */
6213 if (tcode == MINUS_EXPR)
6214 tcode = PLUS_EXPR, op1 = negate_expr (op1);
6216 if (TREE_CODE (op1) != INTEGER_CST)
6219 /* If either OP1 or C are negative, this optimization is not safe for
6220 some of the division and remainder types while for others we need
6221 to change the code. */
6222 if (tree_int_cst_sgn (op1) < 0 || tree_int_cst_sgn (c) < 0)
6224 if (code == CEIL_DIV_EXPR)
6225 code = FLOOR_DIV_EXPR;
6226 else if (code == FLOOR_DIV_EXPR)
6227 code = CEIL_DIV_EXPR;
6228 else if (code != MULT_EXPR
6229 && code != CEIL_MOD_EXPR && code != FLOOR_MOD_EXPR)
6233 /* If it's a multiply or a division/modulus operation of a multiple
6234 of our constant, do the operation and verify it doesn't overflow. */
6235 if (code == MULT_EXPR
6236 || integer_zerop (const_binop (TRUNC_MOD_EXPR, op1, c, 0)))
6238 op1 = const_binop (code, fold_convert (ctype, op1),
6239 fold_convert (ctype, c), 0);
6240 /* We allow the constant to overflow with wrapping semantics. */
6242 || (TREE_OVERFLOW (op1) && !TYPE_OVERFLOW_WRAPS (ctype)))
6248 /* If we have an unsigned type is not a sizetype, we cannot widen
6249 the operation since it will change the result if the original
6250 computation overflowed. */
6251 if (TYPE_UNSIGNED (ctype)
6252 && ! (TREE_CODE (ctype) == INTEGER_TYPE && TYPE_IS_SIZETYPE (ctype))
6256 /* If we were able to eliminate our operation from the first side,
6257 apply our operation to the second side and reform the PLUS. */
6258 if (t1 != 0 && (TREE_CODE (t1) != code || code == MULT_EXPR))
6259 return fold_build2 (tcode, ctype, fold_convert (ctype, t1), op1);
6261 /* The last case is if we are a multiply. In that case, we can
6262 apply the distributive law to commute the multiply and addition
6263 if the multiplication of the constants doesn't overflow. */
6264 if (code == MULT_EXPR)
6265 return fold_build2 (tcode, ctype,
6266 fold_build2 (code, ctype,
6267 fold_convert (ctype, op0),
6268 fold_convert (ctype, c)),
6274 /* We have a special case here if we are doing something like
6275 (C * 8) % 4 since we know that's zero. */
6276 if ((code == TRUNC_MOD_EXPR || code == CEIL_MOD_EXPR
6277 || code == FLOOR_MOD_EXPR || code == ROUND_MOD_EXPR)
6278 /* If the multiplication can overflow we cannot optimize this.
6279 ??? Until we can properly mark individual operations as
6280 not overflowing we need to treat sizetype special here as
6281 stor-layout relies on this opimization to make
6282 DECL_FIELD_BIT_OFFSET always a constant. */
6283 && (TYPE_OVERFLOW_UNDEFINED (TREE_TYPE (t))
6284 || (TREE_CODE (TREE_TYPE (t)) == INTEGER_TYPE
6285 && TYPE_IS_SIZETYPE (TREE_TYPE (t))))
6286 && TREE_CODE (TREE_OPERAND (t, 1)) == INTEGER_CST
6287 && integer_zerop (const_binop (TRUNC_MOD_EXPR, op1, c, 0)))
6289 *strict_overflow_p = true;
6290 return omit_one_operand (type, integer_zero_node, op0);
6293 /* ... fall through ... */
6295 case TRUNC_DIV_EXPR: case CEIL_DIV_EXPR: case FLOOR_DIV_EXPR:
6296 case ROUND_DIV_EXPR: case EXACT_DIV_EXPR:
6297 /* If we can extract our operation from the LHS, do so and return a
6298 new operation. Likewise for the RHS from a MULT_EXPR. Otherwise,
6299 do something only if the second operand is a constant. */
6301 && (t1 = extract_muldiv (op0, c, code, wide_type,
6302 strict_overflow_p)) != 0)
6303 return fold_build2 (tcode, ctype, fold_convert (ctype, t1),
6304 fold_convert (ctype, op1));
6305 else if (tcode == MULT_EXPR && code == MULT_EXPR
6306 && (t1 = extract_muldiv (op1, c, code, wide_type,
6307 strict_overflow_p)) != 0)
6308 return fold_build2 (tcode, ctype, fold_convert (ctype, op0),
6309 fold_convert (ctype, t1));
6310 else if (TREE_CODE (op1) != INTEGER_CST)
6313 /* If these are the same operation types, we can associate them
6314 assuming no overflow. */
6316 && 0 != (t1 = int_const_binop (MULT_EXPR, fold_convert (ctype, op1),
6317 fold_convert (ctype, c), 1))
6318 && 0 != (t1 = force_fit_type_double (ctype, TREE_INT_CST_LOW (t1),
6319 TREE_INT_CST_HIGH (t1),
6320 (TYPE_UNSIGNED (ctype)
6321 && tcode != MULT_EXPR) ? -1 : 1,
6322 TREE_OVERFLOW (t1)))
6323 && !TREE_OVERFLOW (t1))
6324 return fold_build2 (tcode, ctype, fold_convert (ctype, op0), t1);
6326 /* If these operations "cancel" each other, we have the main
6327 optimizations of this pass, which occur when either constant is a
6328 multiple of the other, in which case we replace this with either an
6329 operation or CODE or TCODE.
6331 If we have an unsigned type that is not a sizetype, we cannot do
6332 this since it will change the result if the original computation
6334 if ((TYPE_OVERFLOW_UNDEFINED (ctype)
6335 || (TREE_CODE (ctype) == INTEGER_TYPE && TYPE_IS_SIZETYPE (ctype)))
6336 && ((code == MULT_EXPR && tcode == EXACT_DIV_EXPR)
6337 || (tcode == MULT_EXPR
6338 && code != TRUNC_MOD_EXPR && code != CEIL_MOD_EXPR
6339 && code != FLOOR_MOD_EXPR && code != ROUND_MOD_EXPR
6340 && code != MULT_EXPR)))
6342 if (integer_zerop (const_binop (TRUNC_MOD_EXPR, op1, c, 0)))
6344 if (TYPE_OVERFLOW_UNDEFINED (ctype))
6345 *strict_overflow_p = true;
6346 return fold_build2 (tcode, ctype, fold_convert (ctype, op0),
6347 fold_convert (ctype,
6348 const_binop (TRUNC_DIV_EXPR,
6351 else if (integer_zerop (const_binop (TRUNC_MOD_EXPR, c, op1, 0)))
6353 if (TYPE_OVERFLOW_UNDEFINED (ctype))
6354 *strict_overflow_p = true;
6355 return fold_build2 (code, ctype, fold_convert (ctype, op0),
6356 fold_convert (ctype,
6357 const_binop (TRUNC_DIV_EXPR,
6370 /* Return a node which has the indicated constant VALUE (either 0 or
6371 1), and is of the indicated TYPE. */
6374 constant_boolean_node (int value, tree type)
6376 if (type == integer_type_node)
6377 return value ? integer_one_node : integer_zero_node;
6378 else if (type == boolean_type_node)
6379 return value ? boolean_true_node : boolean_false_node;
6381 return build_int_cst (type, value);
6385 /* Transform `a + (b ? x : y)' into `b ? (a + x) : (a + y)'.
6386 Transform, `a + (x < y)' into `(x < y) ? (a + 1) : (a + 0)'. Here
6387 CODE corresponds to the `+', COND to the `(b ? x : y)' or `(x < y)'
6388 expression, and ARG to `a'. If COND_FIRST_P is nonzero, then the
6389 COND is the first argument to CODE; otherwise (as in the example
6390 given here), it is the second argument. TYPE is the type of the
6391 original expression. Return NULL_TREE if no simplification is
6395 fold_binary_op_with_conditional_arg (enum tree_code code,
6396 tree type, tree op0, tree op1,
6397 tree cond, tree arg, int cond_first_p)
6399 tree cond_type = cond_first_p ? TREE_TYPE (op0) : TREE_TYPE (op1);
6400 tree arg_type = cond_first_p ? TREE_TYPE (op1) : TREE_TYPE (op0);
6401 tree test, true_value, false_value;
6402 tree lhs = NULL_TREE;
6403 tree rhs = NULL_TREE;
6405 /* This transformation is only worthwhile if we don't have to wrap
6406 arg in a SAVE_EXPR, and the operation can be simplified on at least
6407 one of the branches once its pushed inside the COND_EXPR. */
6408 if (!TREE_CONSTANT (arg))
6411 if (TREE_CODE (cond) == COND_EXPR)
6413 test = TREE_OPERAND (cond, 0);
6414 true_value = TREE_OPERAND (cond, 1);
6415 false_value = TREE_OPERAND (cond, 2);
6416 /* If this operand throws an expression, then it does not make
6417 sense to try to perform a logical or arithmetic operation
6419 if (VOID_TYPE_P (TREE_TYPE (true_value)))
6421 if (VOID_TYPE_P (TREE_TYPE (false_value)))
6426 tree testtype = TREE_TYPE (cond);
6428 true_value = constant_boolean_node (true, testtype);
6429 false_value = constant_boolean_node (false, testtype);
6432 arg = fold_convert (arg_type, arg);
6435 true_value = fold_convert (cond_type, true_value);
6437 lhs = fold_build2 (code, type, true_value, arg);
6439 lhs = fold_build2 (code, type, arg, true_value);
6443 false_value = fold_convert (cond_type, false_value);
6445 rhs = fold_build2 (code, type, false_value, arg);
6447 rhs = fold_build2 (code, type, arg, false_value);
6450 test = fold_build3 (COND_EXPR, type, test, lhs, rhs);
6451 return fold_convert (type, test);
6455 /* Subroutine of fold() that checks for the addition of +/- 0.0.
6457 If !NEGATE, return true if ADDEND is +/-0.0 and, for all X of type
6458 TYPE, X + ADDEND is the same as X. If NEGATE, return true if X -
6459 ADDEND is the same as X.
6461 X + 0 and X - 0 both give X when X is NaN, infinite, or nonzero
6462 and finite. The problematic cases are when X is zero, and its mode
6463 has signed zeros. In the case of rounding towards -infinity,
6464 X - 0 is not the same as X because 0 - 0 is -0. In other rounding
6465 modes, X + 0 is not the same as X because -0 + 0 is 0. */
6468 fold_real_zero_addition_p (const_tree type, const_tree addend, int negate)
6470 if (!real_zerop (addend))
6473 /* Don't allow the fold with -fsignaling-nans. */
6474 if (HONOR_SNANS (TYPE_MODE (type)))
6477 /* Allow the fold if zeros aren't signed, or their sign isn't important. */
6478 if (!HONOR_SIGNED_ZEROS (TYPE_MODE (type)))
6481 /* Treat x + -0 as x - 0 and x - -0 as x + 0. */
6482 if (TREE_CODE (addend) == REAL_CST
6483 && REAL_VALUE_MINUS_ZERO (TREE_REAL_CST (addend)))
6486 /* The mode has signed zeros, and we have to honor their sign.
6487 In this situation, there is only one case we can return true for.
6488 X - 0 is the same as X unless rounding towards -infinity is
6490 return negate && !HONOR_SIGN_DEPENDENT_ROUNDING (TYPE_MODE (type));
6493 /* Subroutine of fold() that checks comparisons of built-in math
6494 functions against real constants.
6496 FCODE is the DECL_FUNCTION_CODE of the built-in, CODE is the comparison
6497 operator: EQ_EXPR, NE_EXPR, GT_EXPR, LT_EXPR, GE_EXPR or LE_EXPR. TYPE
6498 is the type of the result and ARG0 and ARG1 are the operands of the
6499 comparison. ARG1 must be a TREE_REAL_CST.
6501 The function returns the constant folded tree if a simplification
6502 can be made, and NULL_TREE otherwise. */
6505 fold_mathfn_compare (enum built_in_function fcode, enum tree_code code,
6506 tree type, tree arg0, tree arg1)
6510 if (BUILTIN_SQRT_P (fcode))
6512 tree arg = CALL_EXPR_ARG (arg0, 0);
6513 enum machine_mode mode = TYPE_MODE (TREE_TYPE (arg0));
6515 c = TREE_REAL_CST (arg1);
6516 if (REAL_VALUE_NEGATIVE (c))
6518 /* sqrt(x) < y is always false, if y is negative. */
6519 if (code == EQ_EXPR || code == LT_EXPR || code == LE_EXPR)
6520 return omit_one_operand (type, integer_zero_node, arg);
6522 /* sqrt(x) > y is always true, if y is negative and we
6523 don't care about NaNs, i.e. negative values of x. */
6524 if (code == NE_EXPR || !HONOR_NANS (mode))
6525 return omit_one_operand (type, integer_one_node, arg);
6527 /* sqrt(x) > y is the same as x >= 0, if y is negative. */
6528 return fold_build2 (GE_EXPR, type, arg,
6529 build_real (TREE_TYPE (arg), dconst0));
6531 else if (code == GT_EXPR || code == GE_EXPR)
6535 REAL_ARITHMETIC (c2, MULT_EXPR, c, c);
6536 real_convert (&c2, mode, &c2);
6538 if (REAL_VALUE_ISINF (c2))
6540 /* sqrt(x) > y is x == +Inf, when y is very large. */
6541 if (HONOR_INFINITIES (mode))
6542 return fold_build2 (EQ_EXPR, type, arg,
6543 build_real (TREE_TYPE (arg), c2));
6545 /* sqrt(x) > y is always false, when y is very large
6546 and we don't care about infinities. */
6547 return omit_one_operand (type, integer_zero_node, arg);
6550 /* sqrt(x) > c is the same as x > c*c. */
6551 return fold_build2 (code, type, arg,
6552 build_real (TREE_TYPE (arg), c2));
6554 else if (code == LT_EXPR || code == LE_EXPR)
6558 REAL_ARITHMETIC (c2, MULT_EXPR, c, c);
6559 real_convert (&c2, mode, &c2);
6561 if (REAL_VALUE_ISINF (c2))
6563 /* sqrt(x) < y is always true, when y is a very large
6564 value and we don't care about NaNs or Infinities. */
6565 if (! HONOR_NANS (mode) && ! HONOR_INFINITIES (mode))
6566 return omit_one_operand (type, integer_one_node, arg);
6568 /* sqrt(x) < y is x != +Inf when y is very large and we
6569 don't care about NaNs. */
6570 if (! HONOR_NANS (mode))
6571 return fold_build2 (NE_EXPR, type, arg,
6572 build_real (TREE_TYPE (arg), c2));
6574 /* sqrt(x) < y is x >= 0 when y is very large and we
6575 don't care about Infinities. */
6576 if (! HONOR_INFINITIES (mode))
6577 return fold_build2 (GE_EXPR, type, arg,
6578 build_real (TREE_TYPE (arg), dconst0));
6580 /* sqrt(x) < y is x >= 0 && x != +Inf, when y is large. */
6581 if (lang_hooks.decls.global_bindings_p () != 0
6582 || CONTAINS_PLACEHOLDER_P (arg))
6585 arg = save_expr (arg);
6586 return fold_build2 (TRUTH_ANDIF_EXPR, type,
6587 fold_build2 (GE_EXPR, type, arg,
6588 build_real (TREE_TYPE (arg),
6590 fold_build2 (NE_EXPR, type, arg,
6591 build_real (TREE_TYPE (arg),
6595 /* sqrt(x) < c is the same as x < c*c, if we ignore NaNs. */
6596 if (! HONOR_NANS (mode))
6597 return fold_build2 (code, type, arg,
6598 build_real (TREE_TYPE (arg), c2));
6600 /* sqrt(x) < c is the same as x >= 0 && x < c*c. */
6601 if (lang_hooks.decls.global_bindings_p () == 0
6602 && ! CONTAINS_PLACEHOLDER_P (arg))
6604 arg = save_expr (arg);
6605 return fold_build2 (TRUTH_ANDIF_EXPR, type,
6606 fold_build2 (GE_EXPR, type, arg,
6607 build_real (TREE_TYPE (arg),
6609 fold_build2 (code, type, arg,
6610 build_real (TREE_TYPE (arg),
6619 /* Subroutine of fold() that optimizes comparisons against Infinities,
6620 either +Inf or -Inf.
6622 CODE is the comparison operator: EQ_EXPR, NE_EXPR, GT_EXPR, LT_EXPR,
6623 GE_EXPR or LE_EXPR. TYPE is the type of the result and ARG0 and ARG1
6624 are the operands of the comparison. ARG1 must be a TREE_REAL_CST.
6626 The function returns the constant folded tree if a simplification
6627 can be made, and NULL_TREE otherwise. */
6630 fold_inf_compare (enum tree_code code, tree type, tree arg0, tree arg1)
6632 enum machine_mode mode;
6633 REAL_VALUE_TYPE max;
6637 mode = TYPE_MODE (TREE_TYPE (arg0));
6639 /* For negative infinity swap the sense of the comparison. */
6640 neg = REAL_VALUE_NEGATIVE (TREE_REAL_CST (arg1));
6642 code = swap_tree_comparison (code);
6647 /* x > +Inf is always false, if with ignore sNANs. */
6648 if (HONOR_SNANS (mode))
6650 return omit_one_operand (type, integer_zero_node, arg0);
6653 /* x <= +Inf is always true, if we don't case about NaNs. */
6654 if (! HONOR_NANS (mode))
6655 return omit_one_operand (type, integer_one_node, arg0);
6657 /* x <= +Inf is the same as x == x, i.e. isfinite(x). */
6658 if (lang_hooks.decls.global_bindings_p () == 0
6659 && ! CONTAINS_PLACEHOLDER_P (arg0))
6661 arg0 = save_expr (arg0);
6662 return fold_build2 (EQ_EXPR, type, arg0, arg0);
6668 /* x == +Inf and x >= +Inf are always equal to x > DBL_MAX. */
6669 real_maxval (&max, neg, mode);
6670 return fold_build2 (neg ? LT_EXPR : GT_EXPR, type,
6671 arg0, build_real (TREE_TYPE (arg0), max));
6674 /* x < +Inf is always equal to x <= DBL_MAX. */
6675 real_maxval (&max, neg, mode);
6676 return fold_build2 (neg ? GE_EXPR : LE_EXPR, type,
6677 arg0, build_real (TREE_TYPE (arg0), max));
6680 /* x != +Inf is always equal to !(x > DBL_MAX). */
6681 real_maxval (&max, neg, mode);
6682 if (! HONOR_NANS (mode))
6683 return fold_build2 (neg ? GE_EXPR : LE_EXPR, type,
6684 arg0, build_real (TREE_TYPE (arg0), max));
6686 temp = fold_build2 (neg ? LT_EXPR : GT_EXPR, type,
6687 arg0, build_real (TREE_TYPE (arg0), max));
6688 return fold_build1 (TRUTH_NOT_EXPR, type, temp);
6697 /* Subroutine of fold() that optimizes comparisons of a division by
6698 a nonzero integer constant against an integer constant, i.e.
6701 CODE is the comparison operator: EQ_EXPR, NE_EXPR, GT_EXPR, LT_EXPR,
6702 GE_EXPR or LE_EXPR. TYPE is the type of the result and ARG0 and ARG1
6703 are the operands of the comparison. ARG1 must be a TREE_REAL_CST.
6705 The function returns the constant folded tree if a simplification
6706 can be made, and NULL_TREE otherwise. */
6709 fold_div_compare (enum tree_code code, tree type, tree arg0, tree arg1)
6711 tree prod, tmp, hi, lo;
6712 tree arg00 = TREE_OPERAND (arg0, 0);
6713 tree arg01 = TREE_OPERAND (arg0, 1);
6714 unsigned HOST_WIDE_INT lpart;
6715 HOST_WIDE_INT hpart;
6716 bool unsigned_p = TYPE_UNSIGNED (TREE_TYPE (arg0));
6720 /* We have to do this the hard way to detect unsigned overflow.
6721 prod = int_const_binop (MULT_EXPR, arg01, arg1, 0); */
6722 overflow = mul_double_with_sign (TREE_INT_CST_LOW (arg01),
6723 TREE_INT_CST_HIGH (arg01),
6724 TREE_INT_CST_LOW (arg1),
6725 TREE_INT_CST_HIGH (arg1),
6726 &lpart, &hpart, unsigned_p);
6727 prod = force_fit_type_double (TREE_TYPE (arg00), lpart, hpart,
6729 neg_overflow = false;
6733 tmp = int_const_binop (MINUS_EXPR, arg01,
6734 build_int_cst (TREE_TYPE (arg01), 1), 0);
6737 /* Likewise hi = int_const_binop (PLUS_EXPR, prod, tmp, 0). */
6738 overflow = add_double_with_sign (TREE_INT_CST_LOW (prod),
6739 TREE_INT_CST_HIGH (prod),
6740 TREE_INT_CST_LOW (tmp),
6741 TREE_INT_CST_HIGH (tmp),
6742 &lpart, &hpart, unsigned_p);
6743 hi = force_fit_type_double (TREE_TYPE (arg00), lpart, hpart,
6744 -1, overflow | TREE_OVERFLOW (prod));
6746 else if (tree_int_cst_sgn (arg01) >= 0)
6748 tmp = int_const_binop (MINUS_EXPR, arg01,
6749 build_int_cst (TREE_TYPE (arg01), 1), 0);
6750 switch (tree_int_cst_sgn (arg1))
6753 neg_overflow = true;
6754 lo = int_const_binop (MINUS_EXPR, prod, tmp, 0);
6759 lo = fold_negate_const (tmp, TREE_TYPE (arg0));
6764 hi = int_const_binop (PLUS_EXPR, prod, tmp, 0);
6774 /* A negative divisor reverses the relational operators. */
6775 code = swap_tree_comparison (code);
6777 tmp = int_const_binop (PLUS_EXPR, arg01,
6778 build_int_cst (TREE_TYPE (arg01), 1), 0);
6779 switch (tree_int_cst_sgn (arg1))
6782 hi = int_const_binop (MINUS_EXPR, prod, tmp, 0);
6787 hi = fold_negate_const (tmp, TREE_TYPE (arg0));
6792 neg_overflow = true;
6793 lo = int_const_binop (PLUS_EXPR, prod, tmp, 0);
6805 if (TREE_OVERFLOW (lo) && TREE_OVERFLOW (hi))
6806 return omit_one_operand (type, integer_zero_node, arg00);
6807 if (TREE_OVERFLOW (hi))
6808 return fold_build2 (GE_EXPR, type, arg00, lo);
6809 if (TREE_OVERFLOW (lo))
6810 return fold_build2 (LE_EXPR, type, arg00, hi);
6811 return build_range_check (type, arg00, 1, lo, hi);
6814 if (TREE_OVERFLOW (lo) && TREE_OVERFLOW (hi))
6815 return omit_one_operand (type, integer_one_node, arg00);
6816 if (TREE_OVERFLOW (hi))
6817 return fold_build2 (LT_EXPR, type, arg00, lo);
6818 if (TREE_OVERFLOW (lo))
6819 return fold_build2 (GT_EXPR, type, arg00, hi);
6820 return build_range_check (type, arg00, 0, lo, hi);
6823 if (TREE_OVERFLOW (lo))
6825 tmp = neg_overflow ? integer_zero_node : integer_one_node;
6826 return omit_one_operand (type, tmp, arg00);
6828 return fold_build2 (LT_EXPR, type, arg00, lo);
6831 if (TREE_OVERFLOW (hi))
6833 tmp = neg_overflow ? integer_zero_node : integer_one_node;
6834 return omit_one_operand (type, tmp, arg00);
6836 return fold_build2 (LE_EXPR, type, arg00, hi);
6839 if (TREE_OVERFLOW (hi))
6841 tmp = neg_overflow ? integer_one_node : integer_zero_node;
6842 return omit_one_operand (type, tmp, arg00);
6844 return fold_build2 (GT_EXPR, type, arg00, hi);
6847 if (TREE_OVERFLOW (lo))
6849 tmp = neg_overflow ? integer_one_node : integer_zero_node;
6850 return omit_one_operand (type, tmp, arg00);
6852 return fold_build2 (GE_EXPR, type, arg00, lo);
6862 /* If CODE with arguments ARG0 and ARG1 represents a single bit
6863 equality/inequality test, then return a simplified form of the test
6864 using a sign testing. Otherwise return NULL. TYPE is the desired
6868 fold_single_bit_test_into_sign_test (enum tree_code code, tree arg0, tree arg1,
6871 /* If this is testing a single bit, we can optimize the test. */
6872 if ((code == NE_EXPR || code == EQ_EXPR)
6873 && TREE_CODE (arg0) == BIT_AND_EXPR && integer_zerop (arg1)
6874 && integer_pow2p (TREE_OPERAND (arg0, 1)))
6876 /* If we have (A & C) != 0 where C is the sign bit of A, convert
6877 this into A < 0. Similarly for (A & C) == 0 into A >= 0. */
6878 tree arg00 = sign_bit_p (TREE_OPERAND (arg0, 0), TREE_OPERAND (arg0, 1));
6880 if (arg00 != NULL_TREE
6881 /* This is only a win if casting to a signed type is cheap,
6882 i.e. when arg00's type is not a partial mode. */
6883 && TYPE_PRECISION (TREE_TYPE (arg00))
6884 == GET_MODE_BITSIZE (TYPE_MODE (TREE_TYPE (arg00))))
6886 tree stype = signed_type_for (TREE_TYPE (arg00));
6887 return fold_build2 (code == EQ_EXPR ? GE_EXPR : LT_EXPR,
6888 result_type, fold_convert (stype, arg00),
6889 build_int_cst (stype, 0));
6896 /* If CODE with arguments ARG0 and ARG1 represents a single bit
6897 equality/inequality test, then return a simplified form of
6898 the test using shifts and logical operations. Otherwise return
6899 NULL. TYPE is the desired result type. */
6902 fold_single_bit_test (enum tree_code code, tree arg0, tree arg1,
6905 /* If this is testing a single bit, we can optimize the test. */
6906 if ((code == NE_EXPR || code == EQ_EXPR)
6907 && TREE_CODE (arg0) == BIT_AND_EXPR && integer_zerop (arg1)
6908 && integer_pow2p (TREE_OPERAND (arg0, 1)))
6910 tree inner = TREE_OPERAND (arg0, 0);
6911 tree type = TREE_TYPE (arg0);
6912 int bitnum = tree_log2 (TREE_OPERAND (arg0, 1));
6913 enum machine_mode operand_mode = TYPE_MODE (type);
6915 tree signed_type, unsigned_type, intermediate_type;
6918 /* First, see if we can fold the single bit test into a sign-bit
6920 tem = fold_single_bit_test_into_sign_test (code, arg0, arg1,
6925 /* Otherwise we have (A & C) != 0 where C is a single bit,
6926 convert that into ((A >> C2) & 1). Where C2 = log2(C).
6927 Similarly for (A & C) == 0. */
6929 /* If INNER is a right shift of a constant and it plus BITNUM does
6930 not overflow, adjust BITNUM and INNER. */
6931 if (TREE_CODE (inner) == RSHIFT_EXPR
6932 && TREE_CODE (TREE_OPERAND (inner, 1)) == INTEGER_CST
6933 && TREE_INT_CST_HIGH (TREE_OPERAND (inner, 1)) == 0
6934 && bitnum < TYPE_PRECISION (type)
6935 && 0 > compare_tree_int (TREE_OPERAND (inner, 1),
6936 bitnum - TYPE_PRECISION (type)))
6938 bitnum += TREE_INT_CST_LOW (TREE_OPERAND (inner, 1));
6939 inner = TREE_OPERAND (inner, 0);
6942 /* If we are going to be able to omit the AND below, we must do our
6943 operations as unsigned. If we must use the AND, we have a choice.
6944 Normally unsigned is faster, but for some machines signed is. */
6945 #ifdef LOAD_EXTEND_OP
6946 ops_unsigned = (LOAD_EXTEND_OP (operand_mode) == SIGN_EXTEND
6947 && !flag_syntax_only) ? 0 : 1;
6952 signed_type = lang_hooks.types.type_for_mode (operand_mode, 0);
6953 unsigned_type = lang_hooks.types.type_for_mode (operand_mode, 1);
6954 intermediate_type = ops_unsigned ? unsigned_type : signed_type;
6955 inner = fold_convert (intermediate_type, inner);
6958 inner = build2 (RSHIFT_EXPR, intermediate_type,
6959 inner, size_int (bitnum));
6961 one = build_int_cst (intermediate_type, 1);
6963 if (code == EQ_EXPR)
6964 inner = fold_build2 (BIT_XOR_EXPR, intermediate_type, inner, one);
6966 /* Put the AND last so it can combine with more things. */
6967 inner = build2 (BIT_AND_EXPR, intermediate_type, inner, one);
6969 /* Make sure to return the proper type. */
6970 inner = fold_convert (result_type, inner);
6977 /* Check whether we are allowed to reorder operands arg0 and arg1,
6978 such that the evaluation of arg1 occurs before arg0. */
6981 reorder_operands_p (const_tree arg0, const_tree arg1)
6983 if (! flag_evaluation_order)
6985 if (TREE_CONSTANT (arg0) || TREE_CONSTANT (arg1))
6987 return ! TREE_SIDE_EFFECTS (arg0)
6988 && ! TREE_SIDE_EFFECTS (arg1);
6991 /* Test whether it is preferable two swap two operands, ARG0 and
6992 ARG1, for example because ARG0 is an integer constant and ARG1
6993 isn't. If REORDER is true, only recommend swapping if we can
6994 evaluate the operands in reverse order. */
6997 tree_swap_operands_p (const_tree arg0, const_tree arg1, bool reorder)
6999 STRIP_SIGN_NOPS (arg0);
7000 STRIP_SIGN_NOPS (arg1);
7002 if (TREE_CODE (arg1) == INTEGER_CST)
7004 if (TREE_CODE (arg0) == INTEGER_CST)
7007 if (TREE_CODE (arg1) == REAL_CST)
7009 if (TREE_CODE (arg0) == REAL_CST)
7012 if (TREE_CODE (arg1) == FIXED_CST)
7014 if (TREE_CODE (arg0) == FIXED_CST)
7017 if (TREE_CODE (arg1) == COMPLEX_CST)
7019 if (TREE_CODE (arg0) == COMPLEX_CST)
7022 if (TREE_CONSTANT (arg1))
7024 if (TREE_CONSTANT (arg0))
7027 if (optimize_function_for_size_p (cfun))
7030 if (reorder && flag_evaluation_order
7031 && (TREE_SIDE_EFFECTS (arg0) || TREE_SIDE_EFFECTS (arg1)))
7034 /* It is preferable to swap two SSA_NAME to ensure a canonical form
7035 for commutative and comparison operators. Ensuring a canonical
7036 form allows the optimizers to find additional redundancies without
7037 having to explicitly check for both orderings. */
7038 if (TREE_CODE (arg0) == SSA_NAME
7039 && TREE_CODE (arg1) == SSA_NAME
7040 && SSA_NAME_VERSION (arg0) > SSA_NAME_VERSION (arg1))
7043 /* Put SSA_NAMEs last. */
7044 if (TREE_CODE (arg1) == SSA_NAME)
7046 if (TREE_CODE (arg0) == SSA_NAME)
7049 /* Put variables last. */
7058 /* Fold comparison ARG0 CODE ARG1 (with result in TYPE), where
7059 ARG0 is extended to a wider type. */
7062 fold_widened_comparison (enum tree_code code, tree type, tree arg0, tree arg1)
7064 tree arg0_unw = get_unwidened (arg0, NULL_TREE);
7066 tree shorter_type, outer_type;
7070 if (arg0_unw == arg0)
7072 shorter_type = TREE_TYPE (arg0_unw);
7074 #ifdef HAVE_canonicalize_funcptr_for_compare
7075 /* Disable this optimization if we're casting a function pointer
7076 type on targets that require function pointer canonicalization. */
7077 if (HAVE_canonicalize_funcptr_for_compare
7078 && TREE_CODE (shorter_type) == POINTER_TYPE
7079 && TREE_CODE (TREE_TYPE (shorter_type)) == FUNCTION_TYPE)
7083 if (TYPE_PRECISION (TREE_TYPE (arg0)) <= TYPE_PRECISION (shorter_type))
7086 arg1_unw = get_unwidened (arg1, NULL_TREE);
7088 /* If possible, express the comparison in the shorter mode. */
7089 if ((code == EQ_EXPR || code == NE_EXPR
7090 || TYPE_UNSIGNED (TREE_TYPE (arg0)) == TYPE_UNSIGNED (shorter_type))
7091 && (TREE_TYPE (arg1_unw) == shorter_type
7092 || ((TYPE_PRECISION (shorter_type)
7093 >= TYPE_PRECISION (TREE_TYPE (arg1_unw)))
7094 && (TYPE_UNSIGNED (shorter_type)
7095 == TYPE_UNSIGNED (TREE_TYPE (arg1_unw))))
7096 || (TREE_CODE (arg1_unw) == INTEGER_CST
7097 && (TREE_CODE (shorter_type) == INTEGER_TYPE
7098 || TREE_CODE (shorter_type) == BOOLEAN_TYPE)
7099 && int_fits_type_p (arg1_unw, shorter_type))))
7100 return fold_build2 (code, type, arg0_unw,
7101 fold_convert (shorter_type, arg1_unw));
7103 if (TREE_CODE (arg1_unw) != INTEGER_CST
7104 || TREE_CODE (shorter_type) != INTEGER_TYPE
7105 || !int_fits_type_p (arg1_unw, shorter_type))
7108 /* If we are comparing with the integer that does not fit into the range
7109 of the shorter type, the result is known. */
7110 outer_type = TREE_TYPE (arg1_unw);
7111 min = lower_bound_in_type (outer_type, shorter_type);
7112 max = upper_bound_in_type (outer_type, shorter_type);
7114 above = integer_nonzerop (fold_relational_const (LT_EXPR, type,
7116 below = integer_nonzerop (fold_relational_const (LT_EXPR, type,
7123 return omit_one_operand (type, integer_zero_node, arg0);
7128 return omit_one_operand (type, integer_one_node, arg0);
7134 return omit_one_operand (type, integer_one_node, arg0);
7136 return omit_one_operand (type, integer_zero_node, arg0);
7141 return omit_one_operand (type, integer_zero_node, arg0);
7143 return omit_one_operand (type, integer_one_node, arg0);
7152 /* Fold comparison ARG0 CODE ARG1 (with result in TYPE), where for
7153 ARG0 just the signedness is changed. */
7156 fold_sign_changed_comparison (enum tree_code code, tree type,
7157 tree arg0, tree arg1)
7160 tree inner_type, outer_type;
7162 if (!CONVERT_EXPR_P (arg0))
7165 outer_type = TREE_TYPE (arg0);
7166 arg0_inner = TREE_OPERAND (arg0, 0);
7167 inner_type = TREE_TYPE (arg0_inner);
7169 #ifdef HAVE_canonicalize_funcptr_for_compare
7170 /* Disable this optimization if we're casting a function pointer
7171 type on targets that require function pointer canonicalization. */
7172 if (HAVE_canonicalize_funcptr_for_compare
7173 && TREE_CODE (inner_type) == POINTER_TYPE
7174 && TREE_CODE (TREE_TYPE (inner_type)) == FUNCTION_TYPE)
7178 if (TYPE_PRECISION (inner_type) != TYPE_PRECISION (outer_type))
7181 /* If the conversion is from an integral subtype to its basetype
7183 if (TREE_TYPE (inner_type) == outer_type)
7186 if (TREE_CODE (arg1) != INTEGER_CST
7187 && !(CONVERT_EXPR_P (arg1)
7188 && TREE_TYPE (TREE_OPERAND (arg1, 0)) == inner_type))
7191 if ((TYPE_UNSIGNED (inner_type) != TYPE_UNSIGNED (outer_type)
7192 || POINTER_TYPE_P (inner_type) != POINTER_TYPE_P (outer_type))
7197 if (TREE_CODE (arg1) == INTEGER_CST)
7198 arg1 = force_fit_type_double (inner_type, TREE_INT_CST_LOW (arg1),
7199 TREE_INT_CST_HIGH (arg1), 0,
7200 TREE_OVERFLOW (arg1));
7202 arg1 = fold_convert (inner_type, arg1);
7204 return fold_build2 (code, type, arg0_inner, arg1);
7207 /* Tries to replace &a[idx] p+ s * delta with &a[idx + delta], if s is
7208 step of the array. Reconstructs s and delta in the case of s * delta
7209 being an integer constant (and thus already folded).
7210 ADDR is the address. MULT is the multiplicative expression.
7211 If the function succeeds, the new address expression is returned. Otherwise
7212 NULL_TREE is returned. */
7215 try_move_mult_to_index (tree addr, tree op1)
7217 tree s, delta, step;
7218 tree ref = TREE_OPERAND (addr, 0), pref;
7223 /* Strip the nops that might be added when converting op1 to sizetype. */
7226 /* Canonicalize op1 into a possibly non-constant delta
7227 and an INTEGER_CST s. */
7228 if (TREE_CODE (op1) == MULT_EXPR)
7230 tree arg0 = TREE_OPERAND (op1, 0), arg1 = TREE_OPERAND (op1, 1);
7235 if (TREE_CODE (arg0) == INTEGER_CST)
7240 else if (TREE_CODE (arg1) == INTEGER_CST)
7248 else if (TREE_CODE (op1) == INTEGER_CST)
7255 /* Simulate we are delta * 1. */
7257 s = integer_one_node;
7260 for (;; ref = TREE_OPERAND (ref, 0))
7262 if (TREE_CODE (ref) == ARRAY_REF)
7264 /* Remember if this was a multi-dimensional array. */
7265 if (TREE_CODE (TREE_OPERAND (ref, 0)) == ARRAY_REF)
7268 itype = TYPE_DOMAIN (TREE_TYPE (TREE_OPERAND (ref, 0)));
7272 step = array_ref_element_size (ref);
7273 if (TREE_CODE (step) != INTEGER_CST)
7278 if (! tree_int_cst_equal (step, s))
7283 /* Try if delta is a multiple of step. */
7284 tree tmp = div_if_zero_remainder (EXACT_DIV_EXPR, op1, step);
7290 /* Only fold here if we can verify we do not overflow one
7291 dimension of a multi-dimensional array. */
7296 if (TREE_CODE (TREE_OPERAND (ref, 1)) != INTEGER_CST
7297 || !INTEGRAL_TYPE_P (itype)
7298 || !TYPE_MAX_VALUE (itype)
7299 || TREE_CODE (TYPE_MAX_VALUE (itype)) != INTEGER_CST)
7302 tmp = fold_binary (PLUS_EXPR, itype,
7303 fold_convert (itype,
7304 TREE_OPERAND (ref, 1)),
7305 fold_convert (itype, delta));
7307 || TREE_CODE (tmp) != INTEGER_CST
7308 || tree_int_cst_lt (TYPE_MAX_VALUE (itype), tmp))
7317 if (!handled_component_p (ref))
7321 /* We found the suitable array reference. So copy everything up to it,
7322 and replace the index. */
7324 pref = TREE_OPERAND (addr, 0);
7325 ret = copy_node (pref);
7330 pref = TREE_OPERAND (pref, 0);
7331 TREE_OPERAND (pos, 0) = copy_node (pref);
7332 pos = TREE_OPERAND (pos, 0);
7335 TREE_OPERAND (pos, 1) = fold_build2 (PLUS_EXPR, itype,
7336 fold_convert (itype,
7337 TREE_OPERAND (pos, 1)),
7338 fold_convert (itype, delta));
7340 return fold_build1 (ADDR_EXPR, TREE_TYPE (addr), ret);
7344 /* Fold A < X && A + 1 > Y to A < X && A >= Y. Normally A + 1 > Y
7345 means A >= Y && A != MAX, but in this case we know that
7346 A < X <= MAX. INEQ is A + 1 > Y, BOUND is A < X. */
7349 fold_to_nonsharp_ineq_using_bound (tree ineq, tree bound)
7351 tree a, typea, type = TREE_TYPE (ineq), a1, diff, y;
7353 if (TREE_CODE (bound) == LT_EXPR)
7354 a = TREE_OPERAND (bound, 0);
7355 else if (TREE_CODE (bound) == GT_EXPR)
7356 a = TREE_OPERAND (bound, 1);
7360 typea = TREE_TYPE (a);
7361 if (!INTEGRAL_TYPE_P (typea)
7362 && !POINTER_TYPE_P (typea))
7365 if (TREE_CODE (ineq) == LT_EXPR)
7367 a1 = TREE_OPERAND (ineq, 1);
7368 y = TREE_OPERAND (ineq, 0);
7370 else if (TREE_CODE (ineq) == GT_EXPR)
7372 a1 = TREE_OPERAND (ineq, 0);
7373 y = TREE_OPERAND (ineq, 1);
7378 if (TREE_TYPE (a1) != typea)
7381 if (POINTER_TYPE_P (typea))
7383 /* Convert the pointer types into integer before taking the difference. */
7384 tree ta = fold_convert (ssizetype, a);
7385 tree ta1 = fold_convert (ssizetype, a1);
7386 diff = fold_binary (MINUS_EXPR, ssizetype, ta1, ta);
7389 diff = fold_binary (MINUS_EXPR, typea, a1, a);
7391 if (!diff || !integer_onep (diff))
7394 return fold_build2 (GE_EXPR, type, a, y);
7397 /* Fold a sum or difference of at least one multiplication.
7398 Returns the folded tree or NULL if no simplification could be made. */
7401 fold_plusminus_mult_expr (enum tree_code code, tree type, tree arg0, tree arg1)
7403 tree arg00, arg01, arg10, arg11;
7404 tree alt0 = NULL_TREE, alt1 = NULL_TREE, same;
7406 /* (A * C) +- (B * C) -> (A+-B) * C.
7407 (A * C) +- A -> A * (C+-1).
7408 We are most concerned about the case where C is a constant,
7409 but other combinations show up during loop reduction. Since
7410 it is not difficult, try all four possibilities. */
7412 if (TREE_CODE (arg0) == MULT_EXPR)
7414 arg00 = TREE_OPERAND (arg0, 0);
7415 arg01 = TREE_OPERAND (arg0, 1);
7417 else if (TREE_CODE (arg0) == INTEGER_CST)
7419 arg00 = build_one_cst (type);
7424 /* We cannot generate constant 1 for fract. */
7425 if (ALL_FRACT_MODE_P (TYPE_MODE (type)))
7428 arg01 = build_one_cst (type);
7430 if (TREE_CODE (arg1) == MULT_EXPR)
7432 arg10 = TREE_OPERAND (arg1, 0);
7433 arg11 = TREE_OPERAND (arg1, 1);
7435 else if (TREE_CODE (arg1) == INTEGER_CST)
7437 arg10 = build_one_cst (type);
7438 /* As we canonicalize A - 2 to A + -2 get rid of that sign for
7439 the purpose of this canonicalization. */
7440 if (TREE_INT_CST_HIGH (arg1) == -1
7441 && negate_expr_p (arg1)
7442 && code == PLUS_EXPR)
7444 arg11 = negate_expr (arg1);
7452 /* We cannot generate constant 1 for fract. */
7453 if (ALL_FRACT_MODE_P (TYPE_MODE (type)))
7456 arg11 = build_one_cst (type);
7460 if (operand_equal_p (arg01, arg11, 0))
7461 same = arg01, alt0 = arg00, alt1 = arg10;
7462 else if (operand_equal_p (arg00, arg10, 0))
7463 same = arg00, alt0 = arg01, alt1 = arg11;
7464 else if (operand_equal_p (arg00, arg11, 0))
7465 same = arg00, alt0 = arg01, alt1 = arg10;
7466 else if (operand_equal_p (arg01, arg10, 0))
7467 same = arg01, alt0 = arg00, alt1 = arg11;
7469 /* No identical multiplicands; see if we can find a common
7470 power-of-two factor in non-power-of-two multiplies. This
7471 can help in multi-dimensional array access. */
7472 else if (host_integerp (arg01, 0)
7473 && host_integerp (arg11, 0))
7475 HOST_WIDE_INT int01, int11, tmp;
7478 int01 = TREE_INT_CST_LOW (arg01);
7479 int11 = TREE_INT_CST_LOW (arg11);
7481 /* Move min of absolute values to int11. */
7482 if ((int01 >= 0 ? int01 : -int01)
7483 < (int11 >= 0 ? int11 : -int11))
7485 tmp = int01, int01 = int11, int11 = tmp;
7486 alt0 = arg00, arg00 = arg10, arg10 = alt0;
7493 if (exact_log2 (abs (int11)) > 0 && int01 % int11 == 0)
7495 alt0 = fold_build2 (MULT_EXPR, TREE_TYPE (arg00), arg00,
7496 build_int_cst (TREE_TYPE (arg00),
7501 maybe_same = alt0, alt0 = alt1, alt1 = maybe_same;
7506 return fold_build2 (MULT_EXPR, type,
7507 fold_build2 (code, type,
7508 fold_convert (type, alt0),
7509 fold_convert (type, alt1)),
7510 fold_convert (type, same));
7515 /* Subroutine of native_encode_expr. Encode the INTEGER_CST
7516 specified by EXPR into the buffer PTR of length LEN bytes.
7517 Return the number of bytes placed in the buffer, or zero
7521 native_encode_int (const_tree expr, unsigned char *ptr, int len)
7523 tree type = TREE_TYPE (expr);
7524 int total_bytes = GET_MODE_SIZE (TYPE_MODE (type));
7525 int byte, offset, word, words;
7526 unsigned char value;
7528 if (total_bytes > len)
7530 words = total_bytes / UNITS_PER_WORD;
7532 for (byte = 0; byte < total_bytes; byte++)
7534 int bitpos = byte * BITS_PER_UNIT;
7535 if (bitpos < HOST_BITS_PER_WIDE_INT)
7536 value = (unsigned char) (TREE_INT_CST_LOW (expr) >> bitpos);
7538 value = (unsigned char) (TREE_INT_CST_HIGH (expr)
7539 >> (bitpos - HOST_BITS_PER_WIDE_INT));
7541 if (total_bytes > UNITS_PER_WORD)
7543 word = byte / UNITS_PER_WORD;
7544 if (WORDS_BIG_ENDIAN)
7545 word = (words - 1) - word;
7546 offset = word * UNITS_PER_WORD;
7547 if (BYTES_BIG_ENDIAN)
7548 offset += (UNITS_PER_WORD - 1) - (byte % UNITS_PER_WORD);
7550 offset += byte % UNITS_PER_WORD;
7553 offset = BYTES_BIG_ENDIAN ? (total_bytes - 1) - byte : byte;
7554 ptr[offset] = value;
7560 /* Subroutine of native_encode_expr. Encode the REAL_CST
7561 specified by EXPR into the buffer PTR of length LEN bytes.
7562 Return the number of bytes placed in the buffer, or zero
7566 native_encode_real (const_tree expr, unsigned char *ptr, int len)
7568 tree type = TREE_TYPE (expr);
7569 int total_bytes = GET_MODE_SIZE (TYPE_MODE (type));
7570 int byte, offset, word, words, bitpos;
7571 unsigned char value;
7573 /* There are always 32 bits in each long, no matter the size of
7574 the hosts long. We handle floating point representations with
7578 if (total_bytes > len)
7580 words = (32 / BITS_PER_UNIT) / UNITS_PER_WORD;
7582 real_to_target (tmp, TREE_REAL_CST_PTR (expr), TYPE_MODE (type));
7584 for (bitpos = 0; bitpos < total_bytes * BITS_PER_UNIT;
7585 bitpos += BITS_PER_UNIT)
7587 byte = (bitpos / BITS_PER_UNIT) & 3;
7588 value = (unsigned char) (tmp[bitpos / 32] >> (bitpos & 31));
7590 if (UNITS_PER_WORD < 4)
7592 word = byte / UNITS_PER_WORD;
7593 if (WORDS_BIG_ENDIAN)
7594 word = (words - 1) - word;
7595 offset = word * UNITS_PER_WORD;
7596 if (BYTES_BIG_ENDIAN)
7597 offset += (UNITS_PER_WORD - 1) - (byte % UNITS_PER_WORD);
7599 offset += byte % UNITS_PER_WORD;
7602 offset = BYTES_BIG_ENDIAN ? 3 - byte : byte;
7603 ptr[offset + ((bitpos / BITS_PER_UNIT) & ~3)] = value;
7608 /* Subroutine of native_encode_expr. Encode the COMPLEX_CST
7609 specified by EXPR into the buffer PTR of length LEN bytes.
7610 Return the number of bytes placed in the buffer, or zero
7614 native_encode_complex (const_tree expr, unsigned char *ptr, int len)
7619 part = TREE_REALPART (expr);
7620 rsize = native_encode_expr (part, ptr, len);
7623 part = TREE_IMAGPART (expr);
7624 isize = native_encode_expr (part, ptr+rsize, len-rsize);
7627 return rsize + isize;
7631 /* Subroutine of native_encode_expr. Encode the VECTOR_CST
7632 specified by EXPR into the buffer PTR of length LEN bytes.
7633 Return the number of bytes placed in the buffer, or zero
7637 native_encode_vector (const_tree expr, unsigned char *ptr, int len)
7639 int i, size, offset, count;
7640 tree itype, elem, elements;
7643 elements = TREE_VECTOR_CST_ELTS (expr);
7644 count = TYPE_VECTOR_SUBPARTS (TREE_TYPE (expr));
7645 itype = TREE_TYPE (TREE_TYPE (expr));
7646 size = GET_MODE_SIZE (TYPE_MODE (itype));
7647 for (i = 0; i < count; i++)
7651 elem = TREE_VALUE (elements);
7652 elements = TREE_CHAIN (elements);
7659 if (native_encode_expr (elem, ptr+offset, len-offset) != size)
7664 if (offset + size > len)
7666 memset (ptr+offset, 0, size);
7674 /* Subroutine of native_encode_expr. Encode the STRING_CST
7675 specified by EXPR into the buffer PTR of length LEN bytes.
7676 Return the number of bytes placed in the buffer, or zero
7680 native_encode_string (const_tree expr, unsigned char *ptr, int len)
7682 tree type = TREE_TYPE (expr);
7683 HOST_WIDE_INT total_bytes;
7685 if (TREE_CODE (type) != ARRAY_TYPE
7686 || TREE_CODE (TREE_TYPE (type)) != INTEGER_TYPE
7687 || GET_MODE_BITSIZE (TYPE_MODE (TREE_TYPE (type))) != BITS_PER_UNIT
7688 || !host_integerp (TYPE_SIZE_UNIT (type), 0))
7690 total_bytes = tree_low_cst (TYPE_SIZE_UNIT (type), 0);
7691 if (total_bytes > len)
7693 if (TREE_STRING_LENGTH (expr) < total_bytes)
7695 memcpy (ptr, TREE_STRING_POINTER (expr), TREE_STRING_LENGTH (expr));
7696 memset (ptr + TREE_STRING_LENGTH (expr), 0,
7697 total_bytes - TREE_STRING_LENGTH (expr));
7700 memcpy (ptr, TREE_STRING_POINTER (expr), total_bytes);
7705 /* Subroutine of fold_view_convert_expr. Encode the INTEGER_CST,
7706 REAL_CST, COMPLEX_CST or VECTOR_CST specified by EXPR into the
7707 buffer PTR of length LEN bytes. Return the number of bytes
7708 placed in the buffer, or zero upon failure. */
7711 native_encode_expr (const_tree expr, unsigned char *ptr, int len)
7713 switch (TREE_CODE (expr))
7716 return native_encode_int (expr, ptr, len);
7719 return native_encode_real (expr, ptr, len);
7722 return native_encode_complex (expr, ptr, len);
7725 return native_encode_vector (expr, ptr, len);
7728 return native_encode_string (expr, ptr, len);
7736 /* Subroutine of native_interpret_expr. Interpret the contents of
7737 the buffer PTR of length LEN as an INTEGER_CST of type TYPE.
7738 If the buffer cannot be interpreted, return NULL_TREE. */
7741 native_interpret_int (tree type, const unsigned char *ptr, int len)
7743 int total_bytes = GET_MODE_SIZE (TYPE_MODE (type));
7744 int byte, offset, word, words;
7745 unsigned char value;
7746 unsigned int HOST_WIDE_INT lo = 0;
7747 HOST_WIDE_INT hi = 0;
7749 if (total_bytes > len)
7751 if (total_bytes * BITS_PER_UNIT > 2 * HOST_BITS_PER_WIDE_INT)
7753 words = total_bytes / UNITS_PER_WORD;
7755 for (byte = 0; byte < total_bytes; byte++)
7757 int bitpos = byte * BITS_PER_UNIT;
7758 if (total_bytes > UNITS_PER_WORD)
7760 word = byte / UNITS_PER_WORD;
7761 if (WORDS_BIG_ENDIAN)
7762 word = (words - 1) - word;
7763 offset = word * UNITS_PER_WORD;
7764 if (BYTES_BIG_ENDIAN)
7765 offset += (UNITS_PER_WORD - 1) - (byte % UNITS_PER_WORD);
7767 offset += byte % UNITS_PER_WORD;
7770 offset = BYTES_BIG_ENDIAN ? (total_bytes - 1) - byte : byte;
7771 value = ptr[offset];
7773 if (bitpos < HOST_BITS_PER_WIDE_INT)
7774 lo |= (unsigned HOST_WIDE_INT) value << bitpos;
7776 hi |= (unsigned HOST_WIDE_INT) value
7777 << (bitpos - HOST_BITS_PER_WIDE_INT);
7780 return build_int_cst_wide_type (type, lo, hi);
7784 /* Subroutine of native_interpret_expr. Interpret the contents of
7785 the buffer PTR of length LEN as a REAL_CST of type TYPE.
7786 If the buffer cannot be interpreted, return NULL_TREE. */
7789 native_interpret_real (tree type, const unsigned char *ptr, int len)
7791 enum machine_mode mode = TYPE_MODE (type);
7792 int total_bytes = GET_MODE_SIZE (mode);
7793 int byte, offset, word, words, bitpos;
7794 unsigned char value;
7795 /* There are always 32 bits in each long, no matter the size of
7796 the hosts long. We handle floating point representations with
7801 total_bytes = GET_MODE_SIZE (TYPE_MODE (type));
7802 if (total_bytes > len || total_bytes > 24)
7804 words = (32 / BITS_PER_UNIT) / UNITS_PER_WORD;
7806 memset (tmp, 0, sizeof (tmp));
7807 for (bitpos = 0; bitpos < total_bytes * BITS_PER_UNIT;
7808 bitpos += BITS_PER_UNIT)
7810 byte = (bitpos / BITS_PER_UNIT) & 3;
7811 if (UNITS_PER_WORD < 4)
7813 word = byte / UNITS_PER_WORD;
7814 if (WORDS_BIG_ENDIAN)
7815 word = (words - 1) - word;
7816 offset = word * UNITS_PER_WORD;
7817 if (BYTES_BIG_ENDIAN)
7818 offset += (UNITS_PER_WORD - 1) - (byte % UNITS_PER_WORD);
7820 offset += byte % UNITS_PER_WORD;
7823 offset = BYTES_BIG_ENDIAN ? 3 - byte : byte;
7824 value = ptr[offset + ((bitpos / BITS_PER_UNIT) & ~3)];
7826 tmp[bitpos / 32] |= (unsigned long)value << (bitpos & 31);
7829 real_from_target (&r, tmp, mode);
7830 return build_real (type, r);
7834 /* Subroutine of native_interpret_expr. Interpret the contents of
7835 the buffer PTR of length LEN as a COMPLEX_CST of type TYPE.
7836 If the buffer cannot be interpreted, return NULL_TREE. */
7839 native_interpret_complex (tree type, const unsigned char *ptr, int len)
7841 tree etype, rpart, ipart;
7844 etype = TREE_TYPE (type);
7845 size = GET_MODE_SIZE (TYPE_MODE (etype));
7848 rpart = native_interpret_expr (etype, ptr, size);
7851 ipart = native_interpret_expr (etype, ptr+size, size);
7854 return build_complex (type, rpart, ipart);
7858 /* Subroutine of native_interpret_expr. Interpret the contents of
7859 the buffer PTR of length LEN as a VECTOR_CST of type TYPE.
7860 If the buffer cannot be interpreted, return NULL_TREE. */
7863 native_interpret_vector (tree type, const unsigned char *ptr, int len)
7865 tree etype, elem, elements;
7868 etype = TREE_TYPE (type);
7869 size = GET_MODE_SIZE (TYPE_MODE (etype));
7870 count = TYPE_VECTOR_SUBPARTS (type);
7871 if (size * count > len)
7874 elements = NULL_TREE;
7875 for (i = count - 1; i >= 0; i--)
7877 elem = native_interpret_expr (etype, ptr+(i*size), size);
7880 elements = tree_cons (NULL_TREE, elem, elements);
7882 return build_vector (type, elements);
7886 /* Subroutine of fold_view_convert_expr. Interpret the contents of
7887 the buffer PTR of length LEN as a constant of type TYPE. For
7888 INTEGRAL_TYPE_P we return an INTEGER_CST, for SCALAR_FLOAT_TYPE_P
7889 we return a REAL_CST, etc... If the buffer cannot be interpreted,
7890 return NULL_TREE. */
7893 native_interpret_expr (tree type, const unsigned char *ptr, int len)
7895 switch (TREE_CODE (type))
7900 return native_interpret_int (type, ptr, len);
7903 return native_interpret_real (type, ptr, len);
7906 return native_interpret_complex (type, ptr, len);
7909 return native_interpret_vector (type, ptr, len);
7917 /* Fold a VIEW_CONVERT_EXPR of a constant expression EXPR to type
7918 TYPE at compile-time. If we're unable to perform the conversion
7919 return NULL_TREE. */
7922 fold_view_convert_expr (tree type, tree expr)
7924 /* We support up to 512-bit values (for V8DFmode). */
7925 unsigned char buffer[64];
7928 /* Check that the host and target are sane. */
7929 if (CHAR_BIT != 8 || BITS_PER_UNIT != 8)
7932 len = native_encode_expr (expr, buffer, sizeof (buffer));
7936 return native_interpret_expr (type, buffer, len);
7939 /* Build an expression for the address of T. Folds away INDIRECT_REF
7940 to avoid confusing the gimplify process. When IN_FOLD is true
7941 avoid modifications of T. */
7944 build_fold_addr_expr_with_type_1 (tree t, tree ptrtype, bool in_fold)
7946 /* The size of the object is not relevant when talking about its address. */
7947 if (TREE_CODE (t) == WITH_SIZE_EXPR)
7948 t = TREE_OPERAND (t, 0);
7950 /* Note: doesn't apply to ALIGN_INDIRECT_REF */
7951 if (TREE_CODE (t) == INDIRECT_REF
7952 || TREE_CODE (t) == MISALIGNED_INDIRECT_REF)
7954 t = TREE_OPERAND (t, 0);
7956 if (TREE_TYPE (t) != ptrtype)
7957 t = build1 (NOP_EXPR, ptrtype, t);
7963 while (handled_component_p (base))
7964 base = TREE_OPERAND (base, 0);
7967 TREE_ADDRESSABLE (base) = 1;
7969 t = build1 (ADDR_EXPR, ptrtype, t);
7972 t = build1 (ADDR_EXPR, ptrtype, t);
7977 /* Build an expression for the address of T with type PTRTYPE. This
7978 function modifies the input parameter 'T' by sometimes setting the
7979 TREE_ADDRESSABLE flag. */
7982 build_fold_addr_expr_with_type (tree t, tree ptrtype)
7984 return build_fold_addr_expr_with_type_1 (t, ptrtype, false);
7987 /* Build an expression for the address of T. This function modifies
7988 the input parameter 'T' by sometimes setting the TREE_ADDRESSABLE
7989 flag. When called from fold functions, use fold_addr_expr instead. */
7992 build_fold_addr_expr (tree t)
7994 return build_fold_addr_expr_with_type_1 (t,
7995 build_pointer_type (TREE_TYPE (t)),
7999 /* Same as build_fold_addr_expr, builds an expression for the address
8000 of T, but avoids touching the input node 't'. Fold functions
8001 should use this version. */
8004 fold_addr_expr (tree t)
8006 tree ptrtype = build_pointer_type (TREE_TYPE (t));
8008 return build_fold_addr_expr_with_type_1 (t, ptrtype, true);
8011 /* Fold a unary expression of code CODE and type TYPE with operand
8012 OP0. Return the folded expression if folding is successful.
8013 Otherwise, return NULL_TREE. */
8016 fold_unary (enum tree_code code, tree type, tree op0)
8020 enum tree_code_class kind = TREE_CODE_CLASS (code);
8022 gcc_assert (IS_EXPR_CODE_CLASS (kind)
8023 && TREE_CODE_LENGTH (code) == 1);
8028 if (CONVERT_EXPR_CODE_P (code)
8029 || code == FLOAT_EXPR || code == ABS_EXPR)
8031 /* Don't use STRIP_NOPS, because signedness of argument type
8033 STRIP_SIGN_NOPS (arg0);
8037 /* Strip any conversions that don't change the mode. This
8038 is safe for every expression, except for a comparison
8039 expression because its signedness is derived from its
8042 Note that this is done as an internal manipulation within
8043 the constant folder, in order to find the simplest
8044 representation of the arguments so that their form can be
8045 studied. In any cases, the appropriate type conversions
8046 should be put back in the tree that will get out of the
8052 if (TREE_CODE_CLASS (code) == tcc_unary)
8054 if (TREE_CODE (arg0) == COMPOUND_EXPR)
8055 return build2 (COMPOUND_EXPR, type, TREE_OPERAND (arg0, 0),
8056 fold_build1 (code, type, TREE_OPERAND (arg0, 1)));
8057 else if (TREE_CODE (arg0) == COND_EXPR)
8059 tree arg01 = TREE_OPERAND (arg0, 1);
8060 tree arg02 = TREE_OPERAND (arg0, 2);
8061 if (! VOID_TYPE_P (TREE_TYPE (arg01)))
8062 arg01 = fold_build1 (code, type, arg01);
8063 if (! VOID_TYPE_P (TREE_TYPE (arg02)))
8064 arg02 = fold_build1 (code, type, arg02);
8065 tem = fold_build3 (COND_EXPR, type, TREE_OPERAND (arg0, 0),
8068 /* If this was a conversion, and all we did was to move into
8069 inside the COND_EXPR, bring it back out. But leave it if
8070 it is a conversion from integer to integer and the
8071 result precision is no wider than a word since such a
8072 conversion is cheap and may be optimized away by combine,
8073 while it couldn't if it were outside the COND_EXPR. Then return
8074 so we don't get into an infinite recursion loop taking the
8075 conversion out and then back in. */
8077 if ((CONVERT_EXPR_CODE_P (code)
8078 || code == NON_LVALUE_EXPR)
8079 && TREE_CODE (tem) == COND_EXPR
8080 && TREE_CODE (TREE_OPERAND (tem, 1)) == code
8081 && TREE_CODE (TREE_OPERAND (tem, 2)) == code
8082 && ! VOID_TYPE_P (TREE_OPERAND (tem, 1))
8083 && ! VOID_TYPE_P (TREE_OPERAND (tem, 2))
8084 && (TREE_TYPE (TREE_OPERAND (TREE_OPERAND (tem, 1), 0))
8085 == TREE_TYPE (TREE_OPERAND (TREE_OPERAND (tem, 2), 0)))
8086 && (! (INTEGRAL_TYPE_P (TREE_TYPE (tem))
8088 (TREE_TYPE (TREE_OPERAND (TREE_OPERAND (tem, 1), 0))))
8089 && TYPE_PRECISION (TREE_TYPE (tem)) <= BITS_PER_WORD)
8090 || flag_syntax_only))
8091 tem = build1 (code, type,
8093 TREE_TYPE (TREE_OPERAND
8094 (TREE_OPERAND (tem, 1), 0)),
8095 TREE_OPERAND (tem, 0),
8096 TREE_OPERAND (TREE_OPERAND (tem, 1), 0),
8097 TREE_OPERAND (TREE_OPERAND (tem, 2), 0)));
8100 else if (COMPARISON_CLASS_P (arg0))
8102 if (TREE_CODE (type) == BOOLEAN_TYPE)
8104 arg0 = copy_node (arg0);
8105 TREE_TYPE (arg0) = type;
8108 else if (TREE_CODE (type) != INTEGER_TYPE)
8109 return fold_build3 (COND_EXPR, type, arg0,
8110 fold_build1 (code, type,
8112 fold_build1 (code, type,
8113 integer_zero_node));
8120 /* Re-association barriers around constants and other re-association
8121 barriers can be removed. */
8122 if (CONSTANT_CLASS_P (op0)
8123 || TREE_CODE (op0) == PAREN_EXPR)
8124 return fold_convert (type, op0);
8129 case FIX_TRUNC_EXPR:
8130 if (TREE_TYPE (op0) == type)
8133 /* If we have (type) (a CMP b) and type is an integral type, return
8134 new expression involving the new type. */
8135 if (COMPARISON_CLASS_P (op0) && INTEGRAL_TYPE_P (type))
8136 return fold_build2 (TREE_CODE (op0), type, TREE_OPERAND (op0, 0),
8137 TREE_OPERAND (op0, 1));
8139 /* Handle cases of two conversions in a row. */
8140 if (CONVERT_EXPR_P (op0))
8142 tree inside_type = TREE_TYPE (TREE_OPERAND (op0, 0));
8143 tree inter_type = TREE_TYPE (op0);
8144 int inside_int = INTEGRAL_TYPE_P (inside_type);
8145 int inside_ptr = POINTER_TYPE_P (inside_type);
8146 int inside_float = FLOAT_TYPE_P (inside_type);
8147 int inside_vec = TREE_CODE (inside_type) == VECTOR_TYPE;
8148 unsigned int inside_prec = TYPE_PRECISION (inside_type);
8149 int inside_unsignedp = TYPE_UNSIGNED (inside_type);
8150 int inter_int = INTEGRAL_TYPE_P (inter_type);
8151 int inter_ptr = POINTER_TYPE_P (inter_type);
8152 int inter_float = FLOAT_TYPE_P (inter_type);
8153 int inter_vec = TREE_CODE (inter_type) == VECTOR_TYPE;
8154 unsigned int inter_prec = TYPE_PRECISION (inter_type);
8155 int inter_unsignedp = TYPE_UNSIGNED (inter_type);
8156 int final_int = INTEGRAL_TYPE_P (type);
8157 int final_ptr = POINTER_TYPE_P (type);
8158 int final_float = FLOAT_TYPE_P (type);
8159 int final_vec = TREE_CODE (type) == VECTOR_TYPE;
8160 unsigned int final_prec = TYPE_PRECISION (type);
8161 int final_unsignedp = TYPE_UNSIGNED (type);
8163 /* In addition to the cases of two conversions in a row
8164 handled below, if we are converting something to its own
8165 type via an object of identical or wider precision, neither
8166 conversion is needed. */
8167 if (TYPE_MAIN_VARIANT (inside_type) == TYPE_MAIN_VARIANT (type)
8168 && (((inter_int || inter_ptr) && final_int)
8169 || (inter_float && final_float))
8170 && inter_prec >= final_prec)
8171 return fold_build1 (code, type, TREE_OPERAND (op0, 0));
8173 /* Likewise, if the intermediate and final types are either both
8174 float or both integer, we don't need the middle conversion if
8175 it is wider than the final type and doesn't change the signedness
8176 (for integers). Avoid this if the final type is a pointer
8177 since then we sometimes need the inner conversion. Likewise if
8178 the outer has a precision not equal to the size of its mode. */
8179 if (((inter_int && inside_int)
8180 || (inter_float && inside_float)
8181 || (inter_vec && inside_vec))
8182 && inter_prec >= inside_prec
8183 && (inter_float || inter_vec
8184 || inter_unsignedp == inside_unsignedp)
8185 && ! (final_prec != GET_MODE_BITSIZE (TYPE_MODE (type))
8186 && TYPE_MODE (type) == TYPE_MODE (inter_type))
8188 && (! final_vec || inter_prec == inside_prec))
8189 return fold_build1 (code, type, TREE_OPERAND (op0, 0));
8191 /* If we have a sign-extension of a zero-extended value, we can
8192 replace that by a single zero-extension. */
8193 if (inside_int && inter_int && final_int
8194 && inside_prec < inter_prec && inter_prec < final_prec
8195 && inside_unsignedp && !inter_unsignedp)
8196 return fold_build1 (code, type, TREE_OPERAND (op0, 0));
8198 /* Two conversions in a row are not needed unless:
8199 - some conversion is floating-point (overstrict for now), or
8200 - some conversion is a vector (overstrict for now), or
8201 - the intermediate type is narrower than both initial and
8203 - the intermediate type and innermost type differ in signedness,
8204 and the outermost type is wider than the intermediate, or
8205 - the initial type is a pointer type and the precisions of the
8206 intermediate and final types differ, or
8207 - the final type is a pointer type and the precisions of the
8208 initial and intermediate types differ. */
8209 if (! inside_float && ! inter_float && ! final_float
8210 && ! inside_vec && ! inter_vec && ! final_vec
8211 && (inter_prec >= inside_prec || inter_prec >= final_prec)
8212 && ! (inside_int && inter_int
8213 && inter_unsignedp != inside_unsignedp
8214 && inter_prec < final_prec)
8215 && ((inter_unsignedp && inter_prec > inside_prec)
8216 == (final_unsignedp && final_prec > inter_prec))
8217 && ! (inside_ptr && inter_prec != final_prec)
8218 && ! (final_ptr && inside_prec != inter_prec)
8219 && ! (final_prec != GET_MODE_BITSIZE (TYPE_MODE (type))
8220 && TYPE_MODE (type) == TYPE_MODE (inter_type)))
8221 return fold_build1 (code, type, TREE_OPERAND (op0, 0));
8224 /* Handle (T *)&A.B.C for A being of type T and B and C
8225 living at offset zero. This occurs frequently in
8226 C++ upcasting and then accessing the base. */
8227 if (TREE_CODE (op0) == ADDR_EXPR
8228 && POINTER_TYPE_P (type)
8229 && handled_component_p (TREE_OPERAND (op0, 0)))
8231 HOST_WIDE_INT bitsize, bitpos;
8233 enum machine_mode mode;
8234 int unsignedp, volatilep;
8235 tree base = TREE_OPERAND (op0, 0);
8236 base = get_inner_reference (base, &bitsize, &bitpos, &offset,
8237 &mode, &unsignedp, &volatilep, false);
8238 /* If the reference was to a (constant) zero offset, we can use
8239 the address of the base if it has the same base type
8240 as the result type. */
8241 if (! offset && bitpos == 0
8242 && TYPE_MAIN_VARIANT (TREE_TYPE (type))
8243 == TYPE_MAIN_VARIANT (TREE_TYPE (base)))
8244 return fold_convert (type, fold_addr_expr (base));
8247 if (TREE_CODE (op0) == MODIFY_EXPR
8248 && TREE_CONSTANT (TREE_OPERAND (op0, 1))
8249 /* Detect assigning a bitfield. */
8250 && !(TREE_CODE (TREE_OPERAND (op0, 0)) == COMPONENT_REF
8252 (TREE_OPERAND (TREE_OPERAND (op0, 0), 1))))
8254 /* Don't leave an assignment inside a conversion
8255 unless assigning a bitfield. */
8256 tem = fold_build1 (code, type, TREE_OPERAND (op0, 1));
8257 /* First do the assignment, then return converted constant. */
8258 tem = build2 (COMPOUND_EXPR, TREE_TYPE (tem), op0, tem);
8259 TREE_NO_WARNING (tem) = 1;
8260 TREE_USED (tem) = 1;
8264 /* Convert (T)(x & c) into (T)x & (T)c, if c is an integer
8265 constants (if x has signed type, the sign bit cannot be set
8266 in c). This folds extension into the BIT_AND_EXPR.
8267 ??? We don't do it for BOOLEAN_TYPE or ENUMERAL_TYPE because they
8268 very likely don't have maximal range for their precision and this
8269 transformation effectively doesn't preserve non-maximal ranges. */
8270 if (TREE_CODE (type) == INTEGER_TYPE
8271 && TREE_CODE (op0) == BIT_AND_EXPR
8272 && TREE_CODE (TREE_OPERAND (op0, 1)) == INTEGER_CST
8273 /* Not if the conversion is to the sub-type. */
8274 && TREE_TYPE (type) != TREE_TYPE (op0))
8277 tree and0 = TREE_OPERAND (and, 0), and1 = TREE_OPERAND (and, 1);
8280 if (TYPE_UNSIGNED (TREE_TYPE (and))
8281 || (TYPE_PRECISION (type)
8282 <= TYPE_PRECISION (TREE_TYPE (and))))
8284 else if (TYPE_PRECISION (TREE_TYPE (and1))
8285 <= HOST_BITS_PER_WIDE_INT
8286 && host_integerp (and1, 1))
8288 unsigned HOST_WIDE_INT cst;
8290 cst = tree_low_cst (and1, 1);
8291 cst &= (HOST_WIDE_INT) -1
8292 << (TYPE_PRECISION (TREE_TYPE (and1)) - 1);
8293 change = (cst == 0);
8294 #ifdef LOAD_EXTEND_OP
8296 && !flag_syntax_only
8297 && (LOAD_EXTEND_OP (TYPE_MODE (TREE_TYPE (and0)))
8300 tree uns = unsigned_type_for (TREE_TYPE (and0));
8301 and0 = fold_convert (uns, and0);
8302 and1 = fold_convert (uns, and1);
8308 tem = force_fit_type_double (type, TREE_INT_CST_LOW (and1),
8309 TREE_INT_CST_HIGH (and1), 0,
8310 TREE_OVERFLOW (and1));
8311 return fold_build2 (BIT_AND_EXPR, type,
8312 fold_convert (type, and0), tem);
8316 /* Convert (T1)(X p+ Y) into ((T1)X p+ Y), for pointer type,
8317 when one of the new casts will fold away. Conservatively we assume
8318 that this happens when X or Y is NOP_EXPR or Y is INTEGER_CST. */
8319 if (POINTER_TYPE_P (type)
8320 && TREE_CODE (arg0) == POINTER_PLUS_EXPR
8321 && (TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST
8322 || TREE_CODE (TREE_OPERAND (arg0, 0)) == NOP_EXPR
8323 || TREE_CODE (TREE_OPERAND (arg0, 1)) == NOP_EXPR))
8325 tree arg00 = TREE_OPERAND (arg0, 0);
8326 tree arg01 = TREE_OPERAND (arg0, 1);
8328 return fold_build2 (TREE_CODE (arg0), type, fold_convert (type, arg00),
8329 fold_convert (sizetype, arg01));
8332 /* Convert (T1)(~(T2)X) into ~(T1)X if T1 and T2 are integral types
8333 of the same precision, and X is an integer type not narrower than
8334 types T1 or T2, i.e. the cast (T2)X isn't an extension. */
8335 if (INTEGRAL_TYPE_P (type)
8336 && TREE_CODE (op0) == BIT_NOT_EXPR
8337 && INTEGRAL_TYPE_P (TREE_TYPE (op0))
8338 && CONVERT_EXPR_P (TREE_OPERAND (op0, 0))
8339 && TYPE_PRECISION (type) == TYPE_PRECISION (TREE_TYPE (op0)))
8341 tem = TREE_OPERAND (TREE_OPERAND (op0, 0), 0);
8342 if (INTEGRAL_TYPE_P (TREE_TYPE (tem))
8343 && TYPE_PRECISION (type) <= TYPE_PRECISION (TREE_TYPE (tem)))
8344 return fold_build1 (BIT_NOT_EXPR, type, fold_convert (type, tem));
8347 /* Convert (T1)(X * Y) into (T1)X * (T1)Y if T1 is narrower than the
8348 type of X and Y (integer types only). */
8349 if (INTEGRAL_TYPE_P (type)
8350 && TREE_CODE (op0) == MULT_EXPR
8351 && INTEGRAL_TYPE_P (TREE_TYPE (op0))
8352 && TYPE_PRECISION (type) < TYPE_PRECISION (TREE_TYPE (op0)))
8354 /* Be careful not to introduce new overflows. */
8356 if (TYPE_OVERFLOW_WRAPS (type))
8359 mult_type = unsigned_type_for (type);
8361 if (TYPE_PRECISION (mult_type) < TYPE_PRECISION (TREE_TYPE (op0)))
8363 tem = fold_build2 (MULT_EXPR, mult_type,
8364 fold_convert (mult_type,
8365 TREE_OPERAND (op0, 0)),
8366 fold_convert (mult_type,
8367 TREE_OPERAND (op0, 1)));
8368 return fold_convert (type, tem);
8372 tem = fold_convert_const (code, type, op0);
8373 return tem ? tem : NULL_TREE;
8375 case FIXED_CONVERT_EXPR:
8376 tem = fold_convert_const (code, type, arg0);
8377 return tem ? tem : NULL_TREE;
8379 case VIEW_CONVERT_EXPR:
8380 if (TREE_TYPE (op0) == type)
8382 if (TREE_CODE (op0) == VIEW_CONVERT_EXPR)
8383 return fold_build1 (VIEW_CONVERT_EXPR, type, TREE_OPERAND (op0, 0));
8385 /* For integral conversions with the same precision or pointer
8386 conversions use a NOP_EXPR instead. */
8387 if ((INTEGRAL_TYPE_P (type)
8388 || POINTER_TYPE_P (type))
8389 && (INTEGRAL_TYPE_P (TREE_TYPE (op0))
8390 || POINTER_TYPE_P (TREE_TYPE (op0)))
8391 && TYPE_PRECISION (type) == TYPE_PRECISION (TREE_TYPE (op0))
8392 /* Do not muck with VIEW_CONVERT_EXPRs that convert from
8393 a sub-type to its base type as generated by the Ada FE. */
8394 && !(INTEGRAL_TYPE_P (TREE_TYPE (op0))
8395 && TREE_TYPE (TREE_TYPE (op0))))
8396 return fold_convert (type, op0);
8398 /* Strip inner integral conversions that do not change the precision. */
8399 if (CONVERT_EXPR_P (op0)
8400 && (INTEGRAL_TYPE_P (TREE_TYPE (op0))
8401 || POINTER_TYPE_P (TREE_TYPE (op0)))
8402 && (INTEGRAL_TYPE_P (TREE_TYPE (TREE_OPERAND (op0, 0)))
8403 || POINTER_TYPE_P (TREE_TYPE (TREE_OPERAND (op0, 0))))
8404 && (TYPE_PRECISION (TREE_TYPE (op0))
8405 == TYPE_PRECISION (TREE_TYPE (TREE_OPERAND (op0, 0)))))
8406 return fold_build1 (VIEW_CONVERT_EXPR, type, TREE_OPERAND (op0, 0));
8408 return fold_view_convert_expr (type, op0);
8411 tem = fold_negate_expr (arg0);
8413 return fold_convert (type, tem);
8417 if (TREE_CODE (arg0) == INTEGER_CST || TREE_CODE (arg0) == REAL_CST)
8418 return fold_abs_const (arg0, type);
8419 else if (TREE_CODE (arg0) == NEGATE_EXPR)
8420 return fold_build1 (ABS_EXPR, type, TREE_OPERAND (arg0, 0));
8421 /* Convert fabs((double)float) into (double)fabsf(float). */
8422 else if (TREE_CODE (arg0) == NOP_EXPR
8423 && TREE_CODE (type) == REAL_TYPE)
8425 tree targ0 = strip_float_extensions (arg0);
8427 return fold_convert (type, fold_build1 (ABS_EXPR,
8431 /* ABS_EXPR<ABS_EXPR<x>> = ABS_EXPR<x> even if flag_wrapv is on. */
8432 else if (TREE_CODE (arg0) == ABS_EXPR)
8434 else if (tree_expr_nonnegative_p (arg0))
8437 /* Strip sign ops from argument. */
8438 if (TREE_CODE (type) == REAL_TYPE)
8440 tem = fold_strip_sign_ops (arg0);
8442 return fold_build1 (ABS_EXPR, type, fold_convert (type, tem));
8447 if (TREE_CODE (TREE_TYPE (arg0)) != COMPLEX_TYPE)
8448 return fold_convert (type, arg0);
8449 if (TREE_CODE (arg0) == COMPLEX_EXPR)
8451 tree itype = TREE_TYPE (type);
8452 tree rpart = fold_convert (itype, TREE_OPERAND (arg0, 0));
8453 tree ipart = fold_convert (itype, TREE_OPERAND (arg0, 1));
8454 return fold_build2 (COMPLEX_EXPR, type, rpart, negate_expr (ipart));
8456 if (TREE_CODE (arg0) == COMPLEX_CST)
8458 tree itype = TREE_TYPE (type);
8459 tree rpart = fold_convert (itype, TREE_REALPART (arg0));
8460 tree ipart = fold_convert (itype, TREE_IMAGPART (arg0));
8461 return build_complex (type, rpart, negate_expr (ipart));
8463 if (TREE_CODE (arg0) == CONJ_EXPR)
8464 return fold_convert (type, TREE_OPERAND (arg0, 0));
8468 if (TREE_CODE (arg0) == INTEGER_CST)
8469 return fold_not_const (arg0, type);
8470 else if (TREE_CODE (arg0) == BIT_NOT_EXPR)
8471 return fold_convert (type, TREE_OPERAND (arg0, 0));
8472 /* Convert ~ (-A) to A - 1. */
8473 else if (INTEGRAL_TYPE_P (type) && TREE_CODE (arg0) == NEGATE_EXPR)
8474 return fold_build2 (MINUS_EXPR, type,
8475 fold_convert (type, TREE_OPERAND (arg0, 0)),
8476 build_int_cst (type, 1));
8477 /* Convert ~ (A - 1) or ~ (A + -1) to -A. */
8478 else if (INTEGRAL_TYPE_P (type)
8479 && ((TREE_CODE (arg0) == MINUS_EXPR
8480 && integer_onep (TREE_OPERAND (arg0, 1)))
8481 || (TREE_CODE (arg0) == PLUS_EXPR
8482 && integer_all_onesp (TREE_OPERAND (arg0, 1)))))
8483 return fold_build1 (NEGATE_EXPR, type,
8484 fold_convert (type, TREE_OPERAND (arg0, 0)));
8485 /* Convert ~(X ^ Y) to ~X ^ Y or X ^ ~Y if ~X or ~Y simplify. */
8486 else if (TREE_CODE (arg0) == BIT_XOR_EXPR
8487 && (tem = fold_unary (BIT_NOT_EXPR, type,
8489 TREE_OPERAND (arg0, 0)))))
8490 return fold_build2 (BIT_XOR_EXPR, type, tem,
8491 fold_convert (type, TREE_OPERAND (arg0, 1)));
8492 else if (TREE_CODE (arg0) == BIT_XOR_EXPR
8493 && (tem = fold_unary (BIT_NOT_EXPR, type,
8495 TREE_OPERAND (arg0, 1)))))
8496 return fold_build2 (BIT_XOR_EXPR, type,
8497 fold_convert (type, TREE_OPERAND (arg0, 0)), tem);
8498 /* Perform BIT_NOT_EXPR on each element individually. */
8499 else if (TREE_CODE (arg0) == VECTOR_CST)
8501 tree elements = TREE_VECTOR_CST_ELTS (arg0), elem, list = NULL_TREE;
8502 int count = TYPE_VECTOR_SUBPARTS (type), i;
8504 for (i = 0; i < count; i++)
8508 elem = TREE_VALUE (elements);
8509 elem = fold_unary (BIT_NOT_EXPR, TREE_TYPE (type), elem);
8510 if (elem == NULL_TREE)
8512 elements = TREE_CHAIN (elements);
8515 elem = build_int_cst (TREE_TYPE (type), -1);
8516 list = tree_cons (NULL_TREE, elem, list);
8519 return build_vector (type, nreverse (list));
8524 case TRUTH_NOT_EXPR:
8525 /* The argument to invert_truthvalue must have Boolean type. */
8526 if (TREE_CODE (TREE_TYPE (arg0)) != BOOLEAN_TYPE)
8527 arg0 = fold_convert (boolean_type_node, arg0);
8529 /* Note that the operand of this must be an int
8530 and its values must be 0 or 1.
8531 ("true" is a fixed value perhaps depending on the language,
8532 but we don't handle values other than 1 correctly yet.) */
8533 tem = fold_truth_not_expr (arg0);
8536 return fold_convert (type, tem);
8539 if (TREE_CODE (TREE_TYPE (arg0)) != COMPLEX_TYPE)
8540 return fold_convert (type, arg0);
8541 if (TREE_CODE (arg0) == COMPLEX_EXPR)
8542 return omit_one_operand (type, TREE_OPERAND (arg0, 0),
8543 TREE_OPERAND (arg0, 1));
8544 if (TREE_CODE (arg0) == COMPLEX_CST)
8545 return fold_convert (type, TREE_REALPART (arg0));
8546 if (TREE_CODE (arg0) == PLUS_EXPR || TREE_CODE (arg0) == MINUS_EXPR)
8548 tree itype = TREE_TYPE (TREE_TYPE (arg0));
8549 tem = fold_build2 (TREE_CODE (arg0), itype,
8550 fold_build1 (REALPART_EXPR, itype,
8551 TREE_OPERAND (arg0, 0)),
8552 fold_build1 (REALPART_EXPR, itype,
8553 TREE_OPERAND (arg0, 1)));
8554 return fold_convert (type, tem);
8556 if (TREE_CODE (arg0) == CONJ_EXPR)
8558 tree itype = TREE_TYPE (TREE_TYPE (arg0));
8559 tem = fold_build1 (REALPART_EXPR, itype, TREE_OPERAND (arg0, 0));
8560 return fold_convert (type, tem);
8562 if (TREE_CODE (arg0) == CALL_EXPR)
8564 tree fn = get_callee_fndecl (arg0);
8565 if (fn && DECL_BUILT_IN_CLASS (fn) == BUILT_IN_NORMAL)
8566 switch (DECL_FUNCTION_CODE (fn))
8568 CASE_FLT_FN (BUILT_IN_CEXPI):
8569 fn = mathfn_built_in (type, BUILT_IN_COS);
8571 return build_call_expr (fn, 1, CALL_EXPR_ARG (arg0, 0));
8581 if (TREE_CODE (TREE_TYPE (arg0)) != COMPLEX_TYPE)
8582 return fold_convert (type, integer_zero_node);
8583 if (TREE_CODE (arg0) == COMPLEX_EXPR)
8584 return omit_one_operand (type, TREE_OPERAND (arg0, 1),
8585 TREE_OPERAND (arg0, 0));
8586 if (TREE_CODE (arg0) == COMPLEX_CST)
8587 return fold_convert (type, TREE_IMAGPART (arg0));
8588 if (TREE_CODE (arg0) == PLUS_EXPR || TREE_CODE (arg0) == MINUS_EXPR)
8590 tree itype = TREE_TYPE (TREE_TYPE (arg0));
8591 tem = fold_build2 (TREE_CODE (arg0), itype,
8592 fold_build1 (IMAGPART_EXPR, itype,
8593 TREE_OPERAND (arg0, 0)),
8594 fold_build1 (IMAGPART_EXPR, itype,
8595 TREE_OPERAND (arg0, 1)));
8596 return fold_convert (type, tem);
8598 if (TREE_CODE (arg0) == CONJ_EXPR)
8600 tree itype = TREE_TYPE (TREE_TYPE (arg0));
8601 tem = fold_build1 (IMAGPART_EXPR, itype, TREE_OPERAND (arg0, 0));
8602 return fold_convert (type, negate_expr (tem));
8604 if (TREE_CODE (arg0) == CALL_EXPR)
8606 tree fn = get_callee_fndecl (arg0);
8607 if (fn && DECL_BUILT_IN_CLASS (fn) == BUILT_IN_NORMAL)
8608 switch (DECL_FUNCTION_CODE (fn))
8610 CASE_FLT_FN (BUILT_IN_CEXPI):
8611 fn = mathfn_built_in (type, BUILT_IN_SIN);
8613 return build_call_expr (fn, 1, CALL_EXPR_ARG (arg0, 0));
8624 } /* switch (code) */
8627 /* Fold a binary expression of code CODE and type TYPE with operands
8628 OP0 and OP1, containing either a MIN-MAX or a MAX-MIN combination.
8629 Return the folded expression if folding is successful. Otherwise,
8630 return NULL_TREE. */
8633 fold_minmax (enum tree_code code, tree type, tree op0, tree op1)
8635 enum tree_code compl_code;
8637 if (code == MIN_EXPR)
8638 compl_code = MAX_EXPR;
8639 else if (code == MAX_EXPR)
8640 compl_code = MIN_EXPR;
8644 /* MIN (MAX (a, b), b) == b. */
8645 if (TREE_CODE (op0) == compl_code
8646 && operand_equal_p (TREE_OPERAND (op0, 1), op1, 0))
8647 return omit_one_operand (type, op1, TREE_OPERAND (op0, 0));
8649 /* MIN (MAX (b, a), b) == b. */
8650 if (TREE_CODE (op0) == compl_code
8651 && operand_equal_p (TREE_OPERAND (op0, 0), op1, 0)
8652 && reorder_operands_p (TREE_OPERAND (op0, 1), op1))
8653 return omit_one_operand (type, op1, TREE_OPERAND (op0, 1));
8655 /* MIN (a, MAX (a, b)) == a. */
8656 if (TREE_CODE (op1) == compl_code
8657 && operand_equal_p (op0, TREE_OPERAND (op1, 0), 0)
8658 && reorder_operands_p (op0, TREE_OPERAND (op1, 1)))
8659 return omit_one_operand (type, op0, TREE_OPERAND (op1, 1));
8661 /* MIN (a, MAX (b, a)) == a. */
8662 if (TREE_CODE (op1) == compl_code
8663 && operand_equal_p (op0, TREE_OPERAND (op1, 1), 0)
8664 && reorder_operands_p (op0, TREE_OPERAND (op1, 0)))
8665 return omit_one_operand (type, op0, TREE_OPERAND (op1, 0));
8670 /* Helper that tries to canonicalize the comparison ARG0 CODE ARG1
8671 by changing CODE to reduce the magnitude of constants involved in
8672 ARG0 of the comparison.
8673 Returns a canonicalized comparison tree if a simplification was
8674 possible, otherwise returns NULL_TREE.
8675 Set *STRICT_OVERFLOW_P to true if the canonicalization is only
8676 valid if signed overflow is undefined. */
8679 maybe_canonicalize_comparison_1 (enum tree_code code, tree type,
8680 tree arg0, tree arg1,
8681 bool *strict_overflow_p)
8683 enum tree_code code0 = TREE_CODE (arg0);
8684 tree t, cst0 = NULL_TREE;
8688 /* Match A +- CST code arg1 and CST code arg1. We can change the
8689 first form only if overflow is undefined. */
8690 if (!((TYPE_OVERFLOW_UNDEFINED (TREE_TYPE (arg0))
8691 /* In principle pointers also have undefined overflow behavior,
8692 but that causes problems elsewhere. */
8693 && !POINTER_TYPE_P (TREE_TYPE (arg0))
8694 && (code0 == MINUS_EXPR
8695 || code0 == PLUS_EXPR)
8696 && TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST)
8697 || code0 == INTEGER_CST))
8700 /* Identify the constant in arg0 and its sign. */
8701 if (code0 == INTEGER_CST)
8704 cst0 = TREE_OPERAND (arg0, 1);
8705 sgn0 = tree_int_cst_sgn (cst0);
8707 /* Overflowed constants and zero will cause problems. */
8708 if (integer_zerop (cst0)
8709 || TREE_OVERFLOW (cst0))
8712 /* See if we can reduce the magnitude of the constant in
8713 arg0 by changing the comparison code. */
8714 if (code0 == INTEGER_CST)
8716 /* CST <= arg1 -> CST-1 < arg1. */
8717 if (code == LE_EXPR && sgn0 == 1)
8719 /* -CST < arg1 -> -CST-1 <= arg1. */
8720 else if (code == LT_EXPR && sgn0 == -1)
8722 /* CST > arg1 -> CST-1 >= arg1. */
8723 else if (code == GT_EXPR && sgn0 == 1)
8725 /* -CST >= arg1 -> -CST-1 > arg1. */
8726 else if (code == GE_EXPR && sgn0 == -1)
8730 /* arg1 code' CST' might be more canonical. */
8735 /* A - CST < arg1 -> A - CST-1 <= arg1. */
8737 && code0 == ((sgn0 == -1) ? PLUS_EXPR : MINUS_EXPR))
8739 /* A + CST > arg1 -> A + CST-1 >= arg1. */
8740 else if (code == GT_EXPR
8741 && code0 == ((sgn0 == -1) ? MINUS_EXPR : PLUS_EXPR))
8743 /* A + CST <= arg1 -> A + CST-1 < arg1. */
8744 else if (code == LE_EXPR
8745 && code0 == ((sgn0 == -1) ? MINUS_EXPR : PLUS_EXPR))
8747 /* A - CST >= arg1 -> A - CST-1 > arg1. */
8748 else if (code == GE_EXPR
8749 && code0 == ((sgn0 == -1) ? PLUS_EXPR : MINUS_EXPR))
8753 *strict_overflow_p = true;
8756 /* Now build the constant reduced in magnitude. But not if that
8757 would produce one outside of its types range. */
8758 if (INTEGRAL_TYPE_P (TREE_TYPE (cst0))
8760 && TYPE_MIN_VALUE (TREE_TYPE (cst0))
8761 && tree_int_cst_equal (cst0, TYPE_MIN_VALUE (TREE_TYPE (cst0))))
8763 && TYPE_MAX_VALUE (TREE_TYPE (cst0))
8764 && tree_int_cst_equal (cst0, TYPE_MAX_VALUE (TREE_TYPE (cst0))))))
8765 /* We cannot swap the comparison here as that would cause us to
8766 endlessly recurse. */
8769 t = int_const_binop (sgn0 == -1 ? PLUS_EXPR : MINUS_EXPR,
8770 cst0, build_int_cst (TREE_TYPE (cst0), 1), 0);
8771 if (code0 != INTEGER_CST)
8772 t = fold_build2 (code0, TREE_TYPE (arg0), TREE_OPERAND (arg0, 0), t);
8774 /* If swapping might yield to a more canonical form, do so. */
8776 return fold_build2 (swap_tree_comparison (code), type, arg1, t);
8778 return fold_build2 (code, type, t, arg1);
8781 /* Canonicalize the comparison ARG0 CODE ARG1 with type TYPE with undefined
8782 overflow further. Try to decrease the magnitude of constants involved
8783 by changing LE_EXPR and GE_EXPR to LT_EXPR and GT_EXPR or vice versa
8784 and put sole constants at the second argument position.
8785 Returns the canonicalized tree if changed, otherwise NULL_TREE. */
8788 maybe_canonicalize_comparison (enum tree_code code, tree type,
8789 tree arg0, tree arg1)
8792 bool strict_overflow_p;
8793 const char * const warnmsg = G_("assuming signed overflow does not occur "
8794 "when reducing constant in comparison");
8796 /* Try canonicalization by simplifying arg0. */
8797 strict_overflow_p = false;
8798 t = maybe_canonicalize_comparison_1 (code, type, arg0, arg1,
8799 &strict_overflow_p);
8802 if (strict_overflow_p)
8803 fold_overflow_warning (warnmsg, WARN_STRICT_OVERFLOW_MAGNITUDE);
8807 /* Try canonicalization by simplifying arg1 using the swapped
8809 code = swap_tree_comparison (code);
8810 strict_overflow_p = false;
8811 t = maybe_canonicalize_comparison_1 (code, type, arg1, arg0,
8812 &strict_overflow_p);
8813 if (t && strict_overflow_p)
8814 fold_overflow_warning (warnmsg, WARN_STRICT_OVERFLOW_MAGNITUDE);
8818 /* Return whether BASE + OFFSET + BITPOS may wrap around the address
8819 space. This is used to avoid issuing overflow warnings for
8820 expressions like &p->x which can not wrap. */
8823 pointer_may_wrap_p (tree base, tree offset, HOST_WIDE_INT bitpos)
8825 unsigned HOST_WIDE_INT offset_low, total_low;
8826 HOST_WIDE_INT size, offset_high, total_high;
8828 if (!POINTER_TYPE_P (TREE_TYPE (base)))
8834 if (offset == NULL_TREE)
8839 else if (TREE_CODE (offset) != INTEGER_CST || TREE_OVERFLOW (offset))
8843 offset_low = TREE_INT_CST_LOW (offset);
8844 offset_high = TREE_INT_CST_HIGH (offset);
8847 if (add_double_with_sign (offset_low, offset_high,
8848 bitpos / BITS_PER_UNIT, 0,
8849 &total_low, &total_high,
8853 if (total_high != 0)
8856 size = int_size_in_bytes (TREE_TYPE (TREE_TYPE (base)));
8860 /* We can do slightly better for SIZE if we have an ADDR_EXPR of an
8862 if (TREE_CODE (base) == ADDR_EXPR)
8864 HOST_WIDE_INT base_size;
8866 base_size = int_size_in_bytes (TREE_TYPE (TREE_OPERAND (base, 0)));
8867 if (base_size > 0 && size < base_size)
8871 return total_low > (unsigned HOST_WIDE_INT) size;
8874 /* Subroutine of fold_binary. This routine performs all of the
8875 transformations that are common to the equality/inequality
8876 operators (EQ_EXPR and NE_EXPR) and the ordering operators
8877 (LT_EXPR, LE_EXPR, GE_EXPR and GT_EXPR). Callers other than
8878 fold_binary should call fold_binary. Fold a comparison with
8879 tree code CODE and type TYPE with operands OP0 and OP1. Return
8880 the folded comparison or NULL_TREE. */
8883 fold_comparison (enum tree_code code, tree type, tree op0, tree op1)
8885 tree arg0, arg1, tem;
8890 STRIP_SIGN_NOPS (arg0);
8891 STRIP_SIGN_NOPS (arg1);
8893 tem = fold_relational_const (code, type, arg0, arg1);
8894 if (tem != NULL_TREE)
8897 /* If one arg is a real or integer constant, put it last. */
8898 if (tree_swap_operands_p (arg0, arg1, true))
8899 return fold_build2 (swap_tree_comparison (code), type, op1, op0);
8901 /* Transform comparisons of the form X +- C1 CMP C2 to X CMP C2 +- C1. */
8902 if ((TREE_CODE (arg0) == PLUS_EXPR || TREE_CODE (arg0) == MINUS_EXPR)
8903 && (TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST
8904 && !TREE_OVERFLOW (TREE_OPERAND (arg0, 1))
8905 && TYPE_OVERFLOW_UNDEFINED (TREE_TYPE (arg1)))
8906 && (TREE_CODE (arg1) == INTEGER_CST
8907 && !TREE_OVERFLOW (arg1)))
8909 tree const1 = TREE_OPERAND (arg0, 1);
8911 tree variable = TREE_OPERAND (arg0, 0);
8914 lhs_add = TREE_CODE (arg0) != PLUS_EXPR;
8916 lhs = fold_build2 (lhs_add ? PLUS_EXPR : MINUS_EXPR,
8917 TREE_TYPE (arg1), const2, const1);
8919 /* If the constant operation overflowed this can be
8920 simplified as a comparison against INT_MAX/INT_MIN. */
8921 if (TREE_CODE (lhs) == INTEGER_CST
8922 && TREE_OVERFLOW (lhs))
8924 int const1_sgn = tree_int_cst_sgn (const1);
8925 enum tree_code code2 = code;
8927 /* Get the sign of the constant on the lhs if the
8928 operation were VARIABLE + CONST1. */
8929 if (TREE_CODE (arg0) == MINUS_EXPR)
8930 const1_sgn = -const1_sgn;
8932 /* The sign of the constant determines if we overflowed
8933 INT_MAX (const1_sgn == -1) or INT_MIN (const1_sgn == 1).
8934 Canonicalize to the INT_MIN overflow by swapping the comparison
8936 if (const1_sgn == -1)
8937 code2 = swap_tree_comparison (code);
8939 /* We now can look at the canonicalized case
8940 VARIABLE + 1 CODE2 INT_MIN
8941 and decide on the result. */
8942 if (code2 == LT_EXPR
8944 || code2 == EQ_EXPR)
8945 return omit_one_operand (type, boolean_false_node, variable);
8946 else if (code2 == NE_EXPR
8948 || code2 == GT_EXPR)
8949 return omit_one_operand (type, boolean_true_node, variable);
8952 if (TREE_CODE (lhs) == TREE_CODE (arg1)
8953 && (TREE_CODE (lhs) != INTEGER_CST
8954 || !TREE_OVERFLOW (lhs)))
8956 fold_overflow_warning (("assuming signed overflow does not occur "
8957 "when changing X +- C1 cmp C2 to "
8959 WARN_STRICT_OVERFLOW_COMPARISON);
8960 return fold_build2 (code, type, variable, lhs);
8964 /* For comparisons of pointers we can decompose it to a compile time
8965 comparison of the base objects and the offsets into the object.
8966 This requires at least one operand being an ADDR_EXPR or a
8967 POINTER_PLUS_EXPR to do more than the operand_equal_p test below. */
8968 if (POINTER_TYPE_P (TREE_TYPE (arg0))
8969 && (TREE_CODE (arg0) == ADDR_EXPR
8970 || TREE_CODE (arg1) == ADDR_EXPR
8971 || TREE_CODE (arg0) == POINTER_PLUS_EXPR
8972 || TREE_CODE (arg1) == POINTER_PLUS_EXPR))
8974 tree base0, base1, offset0 = NULL_TREE, offset1 = NULL_TREE;
8975 HOST_WIDE_INT bitsize, bitpos0 = 0, bitpos1 = 0;
8976 enum machine_mode mode;
8977 int volatilep, unsignedp;
8978 bool indirect_base0 = false, indirect_base1 = false;
8980 /* Get base and offset for the access. Strip ADDR_EXPR for
8981 get_inner_reference, but put it back by stripping INDIRECT_REF
8982 off the base object if possible. indirect_baseN will be true
8983 if baseN is not an address but refers to the object itself. */
8985 if (TREE_CODE (arg0) == ADDR_EXPR)
8987 base0 = get_inner_reference (TREE_OPERAND (arg0, 0),
8988 &bitsize, &bitpos0, &offset0, &mode,
8989 &unsignedp, &volatilep, false);
8990 if (TREE_CODE (base0) == INDIRECT_REF)
8991 base0 = TREE_OPERAND (base0, 0);
8993 indirect_base0 = true;
8995 else if (TREE_CODE (arg0) == POINTER_PLUS_EXPR)
8997 base0 = TREE_OPERAND (arg0, 0);
8998 offset0 = TREE_OPERAND (arg0, 1);
9002 if (TREE_CODE (arg1) == ADDR_EXPR)
9004 base1 = get_inner_reference (TREE_OPERAND (arg1, 0),
9005 &bitsize, &bitpos1, &offset1, &mode,
9006 &unsignedp, &volatilep, false);
9007 if (TREE_CODE (base1) == INDIRECT_REF)
9008 base1 = TREE_OPERAND (base1, 0);
9010 indirect_base1 = true;
9012 else if (TREE_CODE (arg1) == POINTER_PLUS_EXPR)
9014 base1 = TREE_OPERAND (arg1, 0);
9015 offset1 = TREE_OPERAND (arg1, 1);
9018 /* If we have equivalent bases we might be able to simplify. */
9019 if (indirect_base0 == indirect_base1
9020 && operand_equal_p (base0, base1, 0))
9022 /* We can fold this expression to a constant if the non-constant
9023 offset parts are equal. */
9024 if ((offset0 == offset1
9025 || (offset0 && offset1
9026 && operand_equal_p (offset0, offset1, 0)))
9029 || POINTER_TYPE_OVERFLOW_UNDEFINED))
9034 && bitpos0 != bitpos1
9035 && (pointer_may_wrap_p (base0, offset0, bitpos0)
9036 || pointer_may_wrap_p (base1, offset1, bitpos1)))
9037 fold_overflow_warning (("assuming pointer wraparound does not "
9038 "occur when comparing P +- C1 with "
9040 WARN_STRICT_OVERFLOW_CONDITIONAL);
9045 return constant_boolean_node (bitpos0 == bitpos1, type);
9047 return constant_boolean_node (bitpos0 != bitpos1, type);
9049 return constant_boolean_node (bitpos0 < bitpos1, type);
9051 return constant_boolean_node (bitpos0 <= bitpos1, type);
9053 return constant_boolean_node (bitpos0 >= bitpos1, type);
9055 return constant_boolean_node (bitpos0 > bitpos1, type);
9059 /* We can simplify the comparison to a comparison of the variable
9060 offset parts if the constant offset parts are equal.
9061 Be careful to use signed size type here because otherwise we
9062 mess with array offsets in the wrong way. This is possible
9063 because pointer arithmetic is restricted to retain within an
9064 object and overflow on pointer differences is undefined as of
9065 6.5.6/8 and /9 with respect to the signed ptrdiff_t. */
9066 else if (bitpos0 == bitpos1
9067 && ((code == EQ_EXPR || code == NE_EXPR)
9068 || POINTER_TYPE_OVERFLOW_UNDEFINED))
9070 tree signed_size_type_node;
9071 signed_size_type_node = signed_type_for (size_type_node);
9073 /* By converting to signed size type we cover middle-end pointer
9074 arithmetic which operates on unsigned pointer types of size
9075 type size and ARRAY_REF offsets which are properly sign or
9076 zero extended from their type in case it is narrower than
9078 if (offset0 == NULL_TREE)
9079 offset0 = build_int_cst (signed_size_type_node, 0);
9081 offset0 = fold_convert (signed_size_type_node, offset0);
9082 if (offset1 == NULL_TREE)
9083 offset1 = build_int_cst (signed_size_type_node, 0);
9085 offset1 = fold_convert (signed_size_type_node, offset1);
9089 && (pointer_may_wrap_p (base0, offset0, bitpos0)
9090 || pointer_may_wrap_p (base1, offset1, bitpos1)))
9091 fold_overflow_warning (("assuming pointer wraparound does not "
9092 "occur when comparing P +- C1 with "
9094 WARN_STRICT_OVERFLOW_COMPARISON);
9096 return fold_build2 (code, type, offset0, offset1);
9099 /* For non-equal bases we can simplify if they are addresses
9100 of local binding decls or constants. */
9101 else if (indirect_base0 && indirect_base1
9102 /* We know that !operand_equal_p (base0, base1, 0)
9103 because the if condition was false. But make
9104 sure two decls are not the same. */
9106 && TREE_CODE (arg0) == ADDR_EXPR
9107 && TREE_CODE (arg1) == ADDR_EXPR
9108 && (((TREE_CODE (base0) == VAR_DECL
9109 || TREE_CODE (base0) == PARM_DECL)
9110 && (targetm.binds_local_p (base0)
9111 || CONSTANT_CLASS_P (base1)))
9112 || CONSTANT_CLASS_P (base0))
9113 && (((TREE_CODE (base1) == VAR_DECL
9114 || TREE_CODE (base1) == PARM_DECL)
9115 && (targetm.binds_local_p (base1)
9116 || CONSTANT_CLASS_P (base0)))
9117 || CONSTANT_CLASS_P (base1)))
9119 if (code == EQ_EXPR)
9120 return omit_two_operands (type, boolean_false_node, arg0, arg1);
9121 else if (code == NE_EXPR)
9122 return omit_two_operands (type, boolean_true_node, arg0, arg1);
9124 /* For equal offsets we can simplify to a comparison of the
9126 else if (bitpos0 == bitpos1
9128 ? base0 != TREE_OPERAND (arg0, 0) : base0 != arg0)
9130 ? base1 != TREE_OPERAND (arg1, 0) : base1 != arg1)
9131 && ((offset0 == offset1)
9132 || (offset0 && offset1
9133 && operand_equal_p (offset0, offset1, 0))))
9136 base0 = fold_addr_expr (base0);
9138 base1 = fold_addr_expr (base1);
9139 return fold_build2 (code, type, base0, base1);
9143 /* Transform comparisons of the form X +- C1 CMP Y +- C2 to
9144 X CMP Y +- C2 +- C1 for signed X, Y. This is valid if
9145 the resulting offset is smaller in absolute value than the
9147 if (TYPE_OVERFLOW_UNDEFINED (TREE_TYPE (arg0))
9148 && (TREE_CODE (arg0) == PLUS_EXPR || TREE_CODE (arg0) == MINUS_EXPR)
9149 && (TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST
9150 && !TREE_OVERFLOW (TREE_OPERAND (arg0, 1)))
9151 && (TREE_CODE (arg1) == PLUS_EXPR || TREE_CODE (arg1) == MINUS_EXPR)
9152 && (TREE_CODE (TREE_OPERAND (arg1, 1)) == INTEGER_CST
9153 && !TREE_OVERFLOW (TREE_OPERAND (arg1, 1))))
9155 tree const1 = TREE_OPERAND (arg0, 1);
9156 tree const2 = TREE_OPERAND (arg1, 1);
9157 tree variable1 = TREE_OPERAND (arg0, 0);
9158 tree variable2 = TREE_OPERAND (arg1, 0);
9160 const char * const warnmsg = G_("assuming signed overflow does not "
9161 "occur when combining constants around "
9164 /* Put the constant on the side where it doesn't overflow and is
9165 of lower absolute value than before. */
9166 cst = int_const_binop (TREE_CODE (arg0) == TREE_CODE (arg1)
9167 ? MINUS_EXPR : PLUS_EXPR,
9169 if (!TREE_OVERFLOW (cst)
9170 && tree_int_cst_compare (const2, cst) == tree_int_cst_sgn (const2))
9172 fold_overflow_warning (warnmsg, WARN_STRICT_OVERFLOW_COMPARISON);
9173 return fold_build2 (code, type,
9175 fold_build2 (TREE_CODE (arg1), TREE_TYPE (arg1),
9179 cst = int_const_binop (TREE_CODE (arg0) == TREE_CODE (arg1)
9180 ? MINUS_EXPR : PLUS_EXPR,
9182 if (!TREE_OVERFLOW (cst)
9183 && tree_int_cst_compare (const1, cst) == tree_int_cst_sgn (const1))
9185 fold_overflow_warning (warnmsg, WARN_STRICT_OVERFLOW_COMPARISON);
9186 return fold_build2 (code, type,
9187 fold_build2 (TREE_CODE (arg0), TREE_TYPE (arg0),
9193 /* Transform comparisons of the form X * C1 CMP 0 to X CMP 0 in the
9194 signed arithmetic case. That form is created by the compiler
9195 often enough for folding it to be of value. One example is in
9196 computing loop trip counts after Operator Strength Reduction. */
9197 if (TYPE_OVERFLOW_UNDEFINED (TREE_TYPE (arg0))
9198 && TREE_CODE (arg0) == MULT_EXPR
9199 && (TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST
9200 && !TREE_OVERFLOW (TREE_OPERAND (arg0, 1)))
9201 && integer_zerop (arg1))
9203 tree const1 = TREE_OPERAND (arg0, 1);
9204 tree const2 = arg1; /* zero */
9205 tree variable1 = TREE_OPERAND (arg0, 0);
9206 enum tree_code cmp_code = code;
9208 gcc_assert (!integer_zerop (const1));
9210 fold_overflow_warning (("assuming signed overflow does not occur when "
9211 "eliminating multiplication in comparison "
9213 WARN_STRICT_OVERFLOW_COMPARISON);
9215 /* If const1 is negative we swap the sense of the comparison. */
9216 if (tree_int_cst_sgn (const1) < 0)
9217 cmp_code = swap_tree_comparison (cmp_code);
9219 return fold_build2 (cmp_code, type, variable1, const2);
9222 tem = maybe_canonicalize_comparison (code, type, op0, op1);
9226 if (FLOAT_TYPE_P (TREE_TYPE (arg0)))
9228 tree targ0 = strip_float_extensions (arg0);
9229 tree targ1 = strip_float_extensions (arg1);
9230 tree newtype = TREE_TYPE (targ0);
9232 if (TYPE_PRECISION (TREE_TYPE (targ1)) > TYPE_PRECISION (newtype))
9233 newtype = TREE_TYPE (targ1);
9235 /* Fold (double)float1 CMP (double)float2 into float1 CMP float2. */
9236 if (TYPE_PRECISION (newtype) < TYPE_PRECISION (TREE_TYPE (arg0)))
9237 return fold_build2 (code, type, fold_convert (newtype, targ0),
9238 fold_convert (newtype, targ1));
9240 /* (-a) CMP (-b) -> b CMP a */
9241 if (TREE_CODE (arg0) == NEGATE_EXPR
9242 && TREE_CODE (arg1) == NEGATE_EXPR)
9243 return fold_build2 (code, type, TREE_OPERAND (arg1, 0),
9244 TREE_OPERAND (arg0, 0));
9246 if (TREE_CODE (arg1) == REAL_CST)
9248 REAL_VALUE_TYPE cst;
9249 cst = TREE_REAL_CST (arg1);
9251 /* (-a) CMP CST -> a swap(CMP) (-CST) */
9252 if (TREE_CODE (arg0) == NEGATE_EXPR)
9253 return fold_build2 (swap_tree_comparison (code), type,
9254 TREE_OPERAND (arg0, 0),
9255 build_real (TREE_TYPE (arg1),
9256 REAL_VALUE_NEGATE (cst)));
9258 /* IEEE doesn't distinguish +0 and -0 in comparisons. */
9259 /* a CMP (-0) -> a CMP 0 */
9260 if (REAL_VALUE_MINUS_ZERO (cst))
9261 return fold_build2 (code, type, arg0,
9262 build_real (TREE_TYPE (arg1), dconst0));
9264 /* x != NaN is always true, other ops are always false. */
9265 if (REAL_VALUE_ISNAN (cst)
9266 && ! HONOR_SNANS (TYPE_MODE (TREE_TYPE (arg1))))
9268 tem = (code == NE_EXPR) ? integer_one_node : integer_zero_node;
9269 return omit_one_operand (type, tem, arg0);
9272 /* Fold comparisons against infinity. */
9273 if (REAL_VALUE_ISINF (cst))
9275 tem = fold_inf_compare (code, type, arg0, arg1);
9276 if (tem != NULL_TREE)
9281 /* If this is a comparison of a real constant with a PLUS_EXPR
9282 or a MINUS_EXPR of a real constant, we can convert it into a
9283 comparison with a revised real constant as long as no overflow
9284 occurs when unsafe_math_optimizations are enabled. */
9285 if (flag_unsafe_math_optimizations
9286 && TREE_CODE (arg1) == REAL_CST
9287 && (TREE_CODE (arg0) == PLUS_EXPR
9288 || TREE_CODE (arg0) == MINUS_EXPR)
9289 && TREE_CODE (TREE_OPERAND (arg0, 1)) == REAL_CST
9290 && 0 != (tem = const_binop (TREE_CODE (arg0) == PLUS_EXPR
9291 ? MINUS_EXPR : PLUS_EXPR,
9292 arg1, TREE_OPERAND (arg0, 1), 0))
9293 && !TREE_OVERFLOW (tem))
9294 return fold_build2 (code, type, TREE_OPERAND (arg0, 0), tem);
9296 /* Likewise, we can simplify a comparison of a real constant with
9297 a MINUS_EXPR whose first operand is also a real constant, i.e.
9298 (c1 - x) < c2 becomes x > c1-c2. Reordering is allowed on
9299 floating-point types only if -fassociative-math is set. */
9300 if (flag_associative_math
9301 && TREE_CODE (arg1) == REAL_CST
9302 && TREE_CODE (arg0) == MINUS_EXPR
9303 && TREE_CODE (TREE_OPERAND (arg0, 0)) == REAL_CST
9304 && 0 != (tem = const_binop (MINUS_EXPR, TREE_OPERAND (arg0, 0),
9306 && !TREE_OVERFLOW (tem))
9307 return fold_build2 (swap_tree_comparison (code), type,
9308 TREE_OPERAND (arg0, 1), tem);
9310 /* Fold comparisons against built-in math functions. */
9311 if (TREE_CODE (arg1) == REAL_CST
9312 && flag_unsafe_math_optimizations
9313 && ! flag_errno_math)
9315 enum built_in_function fcode = builtin_mathfn_code (arg0);
9317 if (fcode != END_BUILTINS)
9319 tem = fold_mathfn_compare (fcode, code, type, arg0, arg1);
9320 if (tem != NULL_TREE)
9326 if (TREE_CODE (TREE_TYPE (arg0)) == INTEGER_TYPE
9327 && CONVERT_EXPR_P (arg0))
9329 /* If we are widening one operand of an integer comparison,
9330 see if the other operand is similarly being widened. Perhaps we
9331 can do the comparison in the narrower type. */
9332 tem = fold_widened_comparison (code, type, arg0, arg1);
9336 /* Or if we are changing signedness. */
9337 tem = fold_sign_changed_comparison (code, type, arg0, arg1);
9342 /* If this is comparing a constant with a MIN_EXPR or a MAX_EXPR of a
9343 constant, we can simplify it. */
9344 if (TREE_CODE (arg1) == INTEGER_CST
9345 && (TREE_CODE (arg0) == MIN_EXPR
9346 || TREE_CODE (arg0) == MAX_EXPR)
9347 && TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST)
9349 tem = optimize_minmax_comparison (code, type, op0, op1);
9354 /* Simplify comparison of something with itself. (For IEEE
9355 floating-point, we can only do some of these simplifications.) */
9356 if (operand_equal_p (arg0, arg1, 0))
9361 if (! FLOAT_TYPE_P (TREE_TYPE (arg0))
9362 || ! HONOR_NANS (TYPE_MODE (TREE_TYPE (arg0))))
9363 return constant_boolean_node (1, type);
9368 if (! FLOAT_TYPE_P (TREE_TYPE (arg0))
9369 || ! HONOR_NANS (TYPE_MODE (TREE_TYPE (arg0))))
9370 return constant_boolean_node (1, type);
9371 return fold_build2 (EQ_EXPR, type, arg0, arg1);
9374 /* For NE, we can only do this simplification if integer
9375 or we don't honor IEEE floating point NaNs. */
9376 if (FLOAT_TYPE_P (TREE_TYPE (arg0))
9377 && HONOR_NANS (TYPE_MODE (TREE_TYPE (arg0))))
9379 /* ... fall through ... */
9382 return constant_boolean_node (0, type);
9388 /* If we are comparing an expression that just has comparisons
9389 of two integer values, arithmetic expressions of those comparisons,
9390 and constants, we can simplify it. There are only three cases
9391 to check: the two values can either be equal, the first can be
9392 greater, or the second can be greater. Fold the expression for
9393 those three values. Since each value must be 0 or 1, we have
9394 eight possibilities, each of which corresponds to the constant 0
9395 or 1 or one of the six possible comparisons.
9397 This handles common cases like (a > b) == 0 but also handles
9398 expressions like ((x > y) - (y > x)) > 0, which supposedly
9399 occur in macroized code. */
9401 if (TREE_CODE (arg1) == INTEGER_CST && TREE_CODE (arg0) != INTEGER_CST)
9403 tree cval1 = 0, cval2 = 0;
9406 if (twoval_comparison_p (arg0, &cval1, &cval2, &save_p)
9407 /* Don't handle degenerate cases here; they should already
9408 have been handled anyway. */
9409 && cval1 != 0 && cval2 != 0
9410 && ! (TREE_CONSTANT (cval1) && TREE_CONSTANT (cval2))
9411 && TREE_TYPE (cval1) == TREE_TYPE (cval2)
9412 && INTEGRAL_TYPE_P (TREE_TYPE (cval1))
9413 && TYPE_MAX_VALUE (TREE_TYPE (cval1))
9414 && TYPE_MAX_VALUE (TREE_TYPE (cval2))
9415 && ! operand_equal_p (TYPE_MIN_VALUE (TREE_TYPE (cval1)),
9416 TYPE_MAX_VALUE (TREE_TYPE (cval2)), 0))
9418 tree maxval = TYPE_MAX_VALUE (TREE_TYPE (cval1));
9419 tree minval = TYPE_MIN_VALUE (TREE_TYPE (cval1));
9421 /* We can't just pass T to eval_subst in case cval1 or cval2
9422 was the same as ARG1. */
9425 = fold_build2 (code, type,
9426 eval_subst (arg0, cval1, maxval,
9430 = fold_build2 (code, type,
9431 eval_subst (arg0, cval1, maxval,
9435 = fold_build2 (code, type,
9436 eval_subst (arg0, cval1, minval,
9440 /* All three of these results should be 0 or 1. Confirm they are.
9441 Then use those values to select the proper code to use. */
9443 if (TREE_CODE (high_result) == INTEGER_CST
9444 && TREE_CODE (equal_result) == INTEGER_CST
9445 && TREE_CODE (low_result) == INTEGER_CST)
9447 /* Make a 3-bit mask with the high-order bit being the
9448 value for `>', the next for '=', and the low for '<'. */
9449 switch ((integer_onep (high_result) * 4)
9450 + (integer_onep (equal_result) * 2)
9451 + integer_onep (low_result))
9455 return omit_one_operand (type, integer_zero_node, arg0);
9476 return omit_one_operand (type, integer_one_node, arg0);
9480 return save_expr (build2 (code, type, cval1, cval2));
9481 return fold_build2 (code, type, cval1, cval2);
9486 /* We can fold X/C1 op C2 where C1 and C2 are integer constants
9487 into a single range test. */
9488 if ((TREE_CODE (arg0) == TRUNC_DIV_EXPR
9489 || TREE_CODE (arg0) == EXACT_DIV_EXPR)
9490 && TREE_CODE (arg1) == INTEGER_CST
9491 && TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST
9492 && !integer_zerop (TREE_OPERAND (arg0, 1))
9493 && !TREE_OVERFLOW (TREE_OPERAND (arg0, 1))
9494 && !TREE_OVERFLOW (arg1))
9496 tem = fold_div_compare (code, type, arg0, arg1);
9497 if (tem != NULL_TREE)
9501 /* Fold ~X op ~Y as Y op X. */
9502 if (TREE_CODE (arg0) == BIT_NOT_EXPR
9503 && TREE_CODE (arg1) == BIT_NOT_EXPR)
9505 tree cmp_type = TREE_TYPE (TREE_OPERAND (arg0, 0));
9506 return fold_build2 (code, type,
9507 fold_convert (cmp_type, TREE_OPERAND (arg1, 0)),
9508 TREE_OPERAND (arg0, 0));
9511 /* Fold ~X op C as X op' ~C, where op' is the swapped comparison. */
9512 if (TREE_CODE (arg0) == BIT_NOT_EXPR
9513 && TREE_CODE (arg1) == INTEGER_CST)
9515 tree cmp_type = TREE_TYPE (TREE_OPERAND (arg0, 0));
9516 return fold_build2 (swap_tree_comparison (code), type,
9517 TREE_OPERAND (arg0, 0),
9518 fold_build1 (BIT_NOT_EXPR, cmp_type,
9519 fold_convert (cmp_type, arg1)));
9526 /* Subroutine of fold_binary. Optimize complex multiplications of the
9527 form z * conj(z), as pow(realpart(z),2) + pow(imagpart(z),2). The
9528 argument EXPR represents the expression "z" of type TYPE. */
9531 fold_mult_zconjz (tree type, tree expr)
9533 tree itype = TREE_TYPE (type);
9534 tree rpart, ipart, tem;
9536 if (TREE_CODE (expr) == COMPLEX_EXPR)
9538 rpart = TREE_OPERAND (expr, 0);
9539 ipart = TREE_OPERAND (expr, 1);
9541 else if (TREE_CODE (expr) == COMPLEX_CST)
9543 rpart = TREE_REALPART (expr);
9544 ipart = TREE_IMAGPART (expr);
9548 expr = save_expr (expr);
9549 rpart = fold_build1 (REALPART_EXPR, itype, expr);
9550 ipart = fold_build1 (IMAGPART_EXPR, itype, expr);
9553 rpart = save_expr (rpart);
9554 ipart = save_expr (ipart);
9555 tem = fold_build2 (PLUS_EXPR, itype,
9556 fold_build2 (MULT_EXPR, itype, rpart, rpart),
9557 fold_build2 (MULT_EXPR, itype, ipart, ipart));
9558 return fold_build2 (COMPLEX_EXPR, type, tem,
9559 fold_convert (itype, integer_zero_node));
9563 /* Subroutine of fold_binary. If P is the value of EXPR, computes
9564 power-of-two M and (arbitrary) N such that M divides (P-N). This condition
9565 guarantees that P and N have the same least significant log2(M) bits.
9566 N is not otherwise constrained. In particular, N is not normalized to
9567 0 <= N < M as is common. In general, the precise value of P is unknown.
9568 M is chosen as large as possible such that constant N can be determined.
9570 Returns M and sets *RESIDUE to N. */
9572 static unsigned HOST_WIDE_INT
9573 get_pointer_modulus_and_residue (tree expr, unsigned HOST_WIDE_INT *residue)
9575 enum tree_code code;
9579 code = TREE_CODE (expr);
9580 if (code == ADDR_EXPR)
9582 expr = TREE_OPERAND (expr, 0);
9583 if (handled_component_p (expr))
9585 HOST_WIDE_INT bitsize, bitpos;
9587 enum machine_mode mode;
9588 int unsignedp, volatilep;
9590 expr = get_inner_reference (expr, &bitsize, &bitpos, &offset,
9591 &mode, &unsignedp, &volatilep, false);
9592 *residue = bitpos / BITS_PER_UNIT;
9595 if (TREE_CODE (offset) == INTEGER_CST)
9596 *residue += TREE_INT_CST_LOW (offset);
9598 /* We don't handle more complicated offset expressions. */
9603 if (DECL_P (expr) && TREE_CODE (expr) != FUNCTION_DECL)
9604 return DECL_ALIGN_UNIT (expr);
9606 else if (code == POINTER_PLUS_EXPR)
9609 unsigned HOST_WIDE_INT modulus;
9610 enum tree_code inner_code;
9612 op0 = TREE_OPERAND (expr, 0);
9614 modulus = get_pointer_modulus_and_residue (op0, residue);
9616 op1 = TREE_OPERAND (expr, 1);
9618 inner_code = TREE_CODE (op1);
9619 if (inner_code == INTEGER_CST)
9621 *residue += TREE_INT_CST_LOW (op1);
9624 else if (inner_code == MULT_EXPR)
9626 op1 = TREE_OPERAND (op1, 1);
9627 if (TREE_CODE (op1) == INTEGER_CST)
9629 unsigned HOST_WIDE_INT align;
9631 /* Compute the greatest power-of-2 divisor of op1. */
9632 align = TREE_INT_CST_LOW (op1);
9635 /* If align is non-zero and less than *modulus, replace
9636 *modulus with align., If align is 0, then either op1 is 0
9637 or the greatest power-of-2 divisor of op1 doesn't fit in an
9638 unsigned HOST_WIDE_INT. In either case, no additional
9639 constraint is imposed. */
9641 modulus = MIN (modulus, align);
9648 /* If we get here, we were unable to determine anything useful about the
9654 /* Fold a binary expression of code CODE and type TYPE with operands
9655 OP0 and OP1. Return the folded expression if folding is
9656 successful. Otherwise, return NULL_TREE. */
9659 fold_binary (enum tree_code code, tree type, tree op0, tree op1)
9661 enum tree_code_class kind = TREE_CODE_CLASS (code);
9662 tree arg0, arg1, tem;
9663 tree t1 = NULL_TREE;
9664 bool strict_overflow_p;
9666 gcc_assert (IS_EXPR_CODE_CLASS (kind)
9667 && TREE_CODE_LENGTH (code) == 2
9669 && op1 != NULL_TREE);
9674 /* Strip any conversions that don't change the mode. This is
9675 safe for every expression, except for a comparison expression
9676 because its signedness is derived from its operands. So, in
9677 the latter case, only strip conversions that don't change the
9678 signedness. MIN_EXPR/MAX_EXPR also need signedness of arguments
9681 Note that this is done as an internal manipulation within the
9682 constant folder, in order to find the simplest representation
9683 of the arguments so that their form can be studied. In any
9684 cases, the appropriate type conversions should be put back in
9685 the tree that will get out of the constant folder. */
9687 if (kind == tcc_comparison || code == MIN_EXPR || code == MAX_EXPR)
9689 STRIP_SIGN_NOPS (arg0);
9690 STRIP_SIGN_NOPS (arg1);
9698 /* Note that TREE_CONSTANT isn't enough: static var addresses are
9699 constant but we can't do arithmetic on them. */
9700 if ((TREE_CODE (arg0) == INTEGER_CST && TREE_CODE (arg1) == INTEGER_CST)
9701 || (TREE_CODE (arg0) == REAL_CST && TREE_CODE (arg1) == REAL_CST)
9702 || (TREE_CODE (arg0) == FIXED_CST && TREE_CODE (arg1) == FIXED_CST)
9703 || (TREE_CODE (arg0) == FIXED_CST && TREE_CODE (arg1) == INTEGER_CST)
9704 || (TREE_CODE (arg0) == COMPLEX_CST && TREE_CODE (arg1) == COMPLEX_CST)
9705 || (TREE_CODE (arg0) == VECTOR_CST && TREE_CODE (arg1) == VECTOR_CST))
9707 if (kind == tcc_binary)
9709 /* Make sure type and arg0 have the same saturating flag. */
9710 gcc_assert (TYPE_SATURATING (type)
9711 == TYPE_SATURATING (TREE_TYPE (arg0)));
9712 tem = const_binop (code, arg0, arg1, 0);
9714 else if (kind == tcc_comparison)
9715 tem = fold_relational_const (code, type, arg0, arg1);
9719 if (tem != NULL_TREE)
9721 if (TREE_TYPE (tem) != type)
9722 tem = fold_convert (type, tem);
9727 /* If this is a commutative operation, and ARG0 is a constant, move it
9728 to ARG1 to reduce the number of tests below. */
9729 if (commutative_tree_code (code)
9730 && tree_swap_operands_p (arg0, arg1, true))
9731 return fold_build2 (code, type, op1, op0);
9733 /* ARG0 is the first operand of EXPR, and ARG1 is the second operand.
9735 First check for cases where an arithmetic operation is applied to a
9736 compound, conditional, or comparison operation. Push the arithmetic
9737 operation inside the compound or conditional to see if any folding
9738 can then be done. Convert comparison to conditional for this purpose.
9739 The also optimizes non-constant cases that used to be done in
9742 Before we do that, see if this is a BIT_AND_EXPR or a BIT_IOR_EXPR,
9743 one of the operands is a comparison and the other is a comparison, a
9744 BIT_AND_EXPR with the constant 1, or a truth value. In that case, the
9745 code below would make the expression more complex. Change it to a
9746 TRUTH_{AND,OR}_EXPR. Likewise, convert a similar NE_EXPR to
9747 TRUTH_XOR_EXPR and an EQ_EXPR to the inversion of a TRUTH_XOR_EXPR. */
9749 if ((code == BIT_AND_EXPR || code == BIT_IOR_EXPR
9750 || code == EQ_EXPR || code == NE_EXPR)
9751 && ((truth_value_p (TREE_CODE (arg0))
9752 && (truth_value_p (TREE_CODE (arg1))
9753 || (TREE_CODE (arg1) == BIT_AND_EXPR
9754 && integer_onep (TREE_OPERAND (arg1, 1)))))
9755 || (truth_value_p (TREE_CODE (arg1))
9756 && (truth_value_p (TREE_CODE (arg0))
9757 || (TREE_CODE (arg0) == BIT_AND_EXPR
9758 && integer_onep (TREE_OPERAND (arg0, 1)))))))
9760 tem = fold_build2 (code == BIT_AND_EXPR ? TRUTH_AND_EXPR
9761 : code == BIT_IOR_EXPR ? TRUTH_OR_EXPR
9764 fold_convert (boolean_type_node, arg0),
9765 fold_convert (boolean_type_node, arg1));
9767 if (code == EQ_EXPR)
9768 tem = invert_truthvalue (tem);
9770 return fold_convert (type, tem);
9773 if (TREE_CODE_CLASS (code) == tcc_binary
9774 || TREE_CODE_CLASS (code) == tcc_comparison)
9776 if (TREE_CODE (arg0) == COMPOUND_EXPR)
9777 return build2 (COMPOUND_EXPR, type, TREE_OPERAND (arg0, 0),
9778 fold_build2 (code, type,
9779 fold_convert (TREE_TYPE (op0),
9780 TREE_OPERAND (arg0, 1)),
9782 if (TREE_CODE (arg1) == COMPOUND_EXPR
9783 && reorder_operands_p (arg0, TREE_OPERAND (arg1, 0)))
9784 return build2 (COMPOUND_EXPR, type, TREE_OPERAND (arg1, 0),
9785 fold_build2 (code, type, op0,
9786 fold_convert (TREE_TYPE (op1),
9787 TREE_OPERAND (arg1, 1))));
9789 if (TREE_CODE (arg0) == COND_EXPR || COMPARISON_CLASS_P (arg0))
9791 tem = fold_binary_op_with_conditional_arg (code, type, op0, op1,
9793 /*cond_first_p=*/1);
9794 if (tem != NULL_TREE)
9798 if (TREE_CODE (arg1) == COND_EXPR || COMPARISON_CLASS_P (arg1))
9800 tem = fold_binary_op_with_conditional_arg (code, type, op0, op1,
9802 /*cond_first_p=*/0);
9803 if (tem != NULL_TREE)
9810 case POINTER_PLUS_EXPR:
9811 /* 0 +p index -> (type)index */
9812 if (integer_zerop (arg0))
9813 return non_lvalue (fold_convert (type, arg1));
9815 /* PTR +p 0 -> PTR */
9816 if (integer_zerop (arg1))
9817 return non_lvalue (fold_convert (type, arg0));
9819 /* INT +p INT -> (PTR)(INT + INT). Stripping types allows for this. */
9820 if (INTEGRAL_TYPE_P (TREE_TYPE (arg1))
9821 && INTEGRAL_TYPE_P (TREE_TYPE (arg0)))
9822 return fold_convert (type, fold_build2 (PLUS_EXPR, sizetype,
9823 fold_convert (sizetype, arg1),
9824 fold_convert (sizetype, arg0)));
9826 /* index +p PTR -> PTR +p index */
9827 if (POINTER_TYPE_P (TREE_TYPE (arg1))
9828 && INTEGRAL_TYPE_P (TREE_TYPE (arg0)))
9829 return fold_build2 (POINTER_PLUS_EXPR, type,
9830 fold_convert (type, arg1),
9831 fold_convert (sizetype, arg0));
9833 /* (PTR +p B) +p A -> PTR +p (B + A) */
9834 if (TREE_CODE (arg0) == POINTER_PLUS_EXPR)
9837 tree arg01 = fold_convert (sizetype, TREE_OPERAND (arg0, 1));
9838 tree arg00 = TREE_OPERAND (arg0, 0);
9839 inner = fold_build2 (PLUS_EXPR, sizetype,
9840 arg01, fold_convert (sizetype, arg1));
9841 return fold_convert (type,
9842 fold_build2 (POINTER_PLUS_EXPR,
9843 TREE_TYPE (arg00), arg00, inner));
9846 /* PTR_CST +p CST -> CST1 */
9847 if (TREE_CODE (arg0) == INTEGER_CST && TREE_CODE (arg1) == INTEGER_CST)
9848 return fold_build2 (PLUS_EXPR, type, arg0, fold_convert (type, arg1));
9850 /* Try replacing &a[i1] +p c * i2 with &a[i1 + i2], if c is step
9851 of the array. Loop optimizer sometimes produce this type of
9853 if (TREE_CODE (arg0) == ADDR_EXPR)
9855 tem = try_move_mult_to_index (arg0, fold_convert (sizetype, arg1));
9857 return fold_convert (type, tem);
9863 /* PTR + INT -> (INT)(PTR p+ INT) */
9864 if (POINTER_TYPE_P (TREE_TYPE (arg0))
9865 && INTEGRAL_TYPE_P (TREE_TYPE (arg1)))
9866 return fold_convert (type, fold_build2 (POINTER_PLUS_EXPR,
9869 fold_convert (sizetype, arg1)));
9870 /* INT + PTR -> (INT)(PTR p+ INT) */
9871 if (POINTER_TYPE_P (TREE_TYPE (arg1))
9872 && INTEGRAL_TYPE_P (TREE_TYPE (arg0)))
9873 return fold_convert (type, fold_build2 (POINTER_PLUS_EXPR,
9876 fold_convert (sizetype, arg0)));
9877 /* A + (-B) -> A - B */
9878 if (TREE_CODE (arg1) == NEGATE_EXPR)
9879 return fold_build2 (MINUS_EXPR, type,
9880 fold_convert (type, arg0),
9881 fold_convert (type, TREE_OPERAND (arg1, 0)));
9882 /* (-A) + B -> B - A */
9883 if (TREE_CODE (arg0) == NEGATE_EXPR
9884 && reorder_operands_p (TREE_OPERAND (arg0, 0), arg1))
9885 return fold_build2 (MINUS_EXPR, type,
9886 fold_convert (type, arg1),
9887 fold_convert (type, TREE_OPERAND (arg0, 0)));
9889 if (INTEGRAL_TYPE_P (type))
9891 /* Convert ~A + 1 to -A. */
9892 if (TREE_CODE (arg0) == BIT_NOT_EXPR
9893 && integer_onep (arg1))
9894 return fold_build1 (NEGATE_EXPR, type,
9895 fold_convert (type, TREE_OPERAND (arg0, 0)));
9898 if (TREE_CODE (arg0) == BIT_NOT_EXPR
9899 && !TYPE_OVERFLOW_TRAPS (type))
9901 tree tem = TREE_OPERAND (arg0, 0);
9904 if (operand_equal_p (tem, arg1, 0))
9906 t1 = build_int_cst_type (type, -1);
9907 return omit_one_operand (type, t1, arg1);
9912 if (TREE_CODE (arg1) == BIT_NOT_EXPR
9913 && !TYPE_OVERFLOW_TRAPS (type))
9915 tree tem = TREE_OPERAND (arg1, 0);
9918 if (operand_equal_p (arg0, tem, 0))
9920 t1 = build_int_cst_type (type, -1);
9921 return omit_one_operand (type, t1, arg0);
9925 /* X + (X / CST) * -CST is X % CST. */
9926 if (TREE_CODE (arg1) == MULT_EXPR
9927 && TREE_CODE (TREE_OPERAND (arg1, 0)) == TRUNC_DIV_EXPR
9928 && operand_equal_p (arg0,
9929 TREE_OPERAND (TREE_OPERAND (arg1, 0), 0), 0))
9931 tree cst0 = TREE_OPERAND (TREE_OPERAND (arg1, 0), 1);
9932 tree cst1 = TREE_OPERAND (arg1, 1);
9933 tree sum = fold_binary (PLUS_EXPR, TREE_TYPE (cst1), cst1, cst0);
9934 if (sum && integer_zerop (sum))
9935 return fold_convert (type,
9936 fold_build2 (TRUNC_MOD_EXPR,
9937 TREE_TYPE (arg0), arg0, cst0));
9941 /* Handle (A1 * C1) + (A2 * C2) with A1, A2 or C1, C2 being the
9942 same or one. Make sure type is not saturating.
9943 fold_plusminus_mult_expr will re-associate. */
9944 if ((TREE_CODE (arg0) == MULT_EXPR
9945 || TREE_CODE (arg1) == MULT_EXPR)
9946 && !TYPE_SATURATING (type)
9947 && (!FLOAT_TYPE_P (type) || flag_associative_math))
9949 tree tem = fold_plusminus_mult_expr (code, type, arg0, arg1);
9954 if (! FLOAT_TYPE_P (type))
9956 if (integer_zerop (arg1))
9957 return non_lvalue (fold_convert (type, arg0));
9959 /* If we are adding two BIT_AND_EXPR's, both of which are and'ing
9960 with a constant, and the two constants have no bits in common,
9961 we should treat this as a BIT_IOR_EXPR since this may produce more
9963 if (TREE_CODE (arg0) == BIT_AND_EXPR
9964 && TREE_CODE (arg1) == BIT_AND_EXPR
9965 && TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST
9966 && TREE_CODE (TREE_OPERAND (arg1, 1)) == INTEGER_CST
9967 && integer_zerop (const_binop (BIT_AND_EXPR,
9968 TREE_OPERAND (arg0, 1),
9969 TREE_OPERAND (arg1, 1), 0)))
9971 code = BIT_IOR_EXPR;
9975 /* Reassociate (plus (plus (mult) (foo)) (mult)) as
9976 (plus (plus (mult) (mult)) (foo)) so that we can
9977 take advantage of the factoring cases below. */
9978 if (((TREE_CODE (arg0) == PLUS_EXPR
9979 || TREE_CODE (arg0) == MINUS_EXPR)
9980 && TREE_CODE (arg1) == MULT_EXPR)
9981 || ((TREE_CODE (arg1) == PLUS_EXPR
9982 || TREE_CODE (arg1) == MINUS_EXPR)
9983 && TREE_CODE (arg0) == MULT_EXPR))
9985 tree parg0, parg1, parg, marg;
9986 enum tree_code pcode;
9988 if (TREE_CODE (arg1) == MULT_EXPR)
9989 parg = arg0, marg = arg1;
9991 parg = arg1, marg = arg0;
9992 pcode = TREE_CODE (parg);
9993 parg0 = TREE_OPERAND (parg, 0);
9994 parg1 = TREE_OPERAND (parg, 1);
9998 if (TREE_CODE (parg0) == MULT_EXPR
9999 && TREE_CODE (parg1) != MULT_EXPR)
10000 return fold_build2 (pcode, type,
10001 fold_build2 (PLUS_EXPR, type,
10002 fold_convert (type, parg0),
10003 fold_convert (type, marg)),
10004 fold_convert (type, parg1));
10005 if (TREE_CODE (parg0) != MULT_EXPR
10006 && TREE_CODE (parg1) == MULT_EXPR)
10007 return fold_build2 (PLUS_EXPR, type,
10008 fold_convert (type, parg0),
10009 fold_build2 (pcode, type,
10010 fold_convert (type, marg),
10011 fold_convert (type,
10017 /* See if ARG1 is zero and X + ARG1 reduces to X. */
10018 if (fold_real_zero_addition_p (TREE_TYPE (arg0), arg1, 0))
10019 return non_lvalue (fold_convert (type, arg0));
10021 /* Likewise if the operands are reversed. */
10022 if (fold_real_zero_addition_p (TREE_TYPE (arg1), arg0, 0))
10023 return non_lvalue (fold_convert (type, arg1));
10025 /* Convert X + -C into X - C. */
10026 if (TREE_CODE (arg1) == REAL_CST
10027 && REAL_VALUE_NEGATIVE (TREE_REAL_CST (arg1)))
10029 tem = fold_negate_const (arg1, type);
10030 if (!TREE_OVERFLOW (arg1) || !flag_trapping_math)
10031 return fold_build2 (MINUS_EXPR, type,
10032 fold_convert (type, arg0),
10033 fold_convert (type, tem));
10036 /* Fold __complex__ ( x, 0 ) + __complex__ ( 0, y )
10037 to __complex__ ( x, y ). This is not the same for SNaNs or
10038 if signed zeros are involved. */
10039 if (!HONOR_SNANS (TYPE_MODE (TREE_TYPE (arg0)))
10040 && !HONOR_SIGNED_ZEROS (TYPE_MODE (TREE_TYPE (arg0)))
10041 && COMPLEX_FLOAT_TYPE_P (TREE_TYPE (arg0)))
10043 tree rtype = TREE_TYPE (TREE_TYPE (arg0));
10044 tree arg0r = fold_unary (REALPART_EXPR, rtype, arg0);
10045 tree arg0i = fold_unary (IMAGPART_EXPR, rtype, arg0);
10046 bool arg0rz = false, arg0iz = false;
10047 if ((arg0r && (arg0rz = real_zerop (arg0r)))
10048 || (arg0i && (arg0iz = real_zerop (arg0i))))
10050 tree arg1r = fold_unary (REALPART_EXPR, rtype, arg1);
10051 tree arg1i = fold_unary (IMAGPART_EXPR, rtype, arg1);
10052 if (arg0rz && arg1i && real_zerop (arg1i))
10054 tree rp = arg1r ? arg1r
10055 : build1 (REALPART_EXPR, rtype, arg1);
10056 tree ip = arg0i ? arg0i
10057 : build1 (IMAGPART_EXPR, rtype, arg0);
10058 return fold_build2 (COMPLEX_EXPR, type, rp, ip);
10060 else if (arg0iz && arg1r && real_zerop (arg1r))
10062 tree rp = arg0r ? arg0r
10063 : build1 (REALPART_EXPR, rtype, arg0);
10064 tree ip = arg1i ? arg1i
10065 : build1 (IMAGPART_EXPR, rtype, arg1);
10066 return fold_build2 (COMPLEX_EXPR, type, rp, ip);
10071 if (flag_unsafe_math_optimizations
10072 && (TREE_CODE (arg0) == RDIV_EXPR || TREE_CODE (arg0) == MULT_EXPR)
10073 && (TREE_CODE (arg1) == RDIV_EXPR || TREE_CODE (arg1) == MULT_EXPR)
10074 && (tem = distribute_real_division (code, type, arg0, arg1)))
10077 /* Convert x+x into x*2.0. */
10078 if (operand_equal_p (arg0, arg1, 0)
10079 && SCALAR_FLOAT_TYPE_P (type))
10080 return fold_build2 (MULT_EXPR, type, arg0,
10081 build_real (type, dconst2));
10083 /* Convert a + (b*c + d*e) into (a + b*c) + d*e.
10084 We associate floats only if the user has specified
10085 -fassociative-math. */
10086 if (flag_associative_math
10087 && TREE_CODE (arg1) == PLUS_EXPR
10088 && TREE_CODE (arg0) != MULT_EXPR)
10090 tree tree10 = TREE_OPERAND (arg1, 0);
10091 tree tree11 = TREE_OPERAND (arg1, 1);
10092 if (TREE_CODE (tree11) == MULT_EXPR
10093 && TREE_CODE (tree10) == MULT_EXPR)
10096 tree0 = fold_build2 (PLUS_EXPR, type, arg0, tree10);
10097 return fold_build2 (PLUS_EXPR, type, tree0, tree11);
10100 /* Convert (b*c + d*e) + a into b*c + (d*e +a).
10101 We associate floats only if the user has specified
10102 -fassociative-math. */
10103 if (flag_associative_math
10104 && TREE_CODE (arg0) == PLUS_EXPR
10105 && TREE_CODE (arg1) != MULT_EXPR)
10107 tree tree00 = TREE_OPERAND (arg0, 0);
10108 tree tree01 = TREE_OPERAND (arg0, 1);
10109 if (TREE_CODE (tree01) == MULT_EXPR
10110 && TREE_CODE (tree00) == MULT_EXPR)
10113 tree0 = fold_build2 (PLUS_EXPR, type, tree01, arg1);
10114 return fold_build2 (PLUS_EXPR, type, tree00, tree0);
10120 /* (A << C1) + (A >> C2) if A is unsigned and C1+C2 is the size of A
10121 is a rotate of A by C1 bits. */
10122 /* (A << B) + (A >> (Z - B)) if A is unsigned and Z is the size of A
10123 is a rotate of A by B bits. */
10125 enum tree_code code0, code1;
10127 code0 = TREE_CODE (arg0);
10128 code1 = TREE_CODE (arg1);
10129 if (((code0 == RSHIFT_EXPR && code1 == LSHIFT_EXPR)
10130 || (code1 == RSHIFT_EXPR && code0 == LSHIFT_EXPR))
10131 && operand_equal_p (TREE_OPERAND (arg0, 0),
10132 TREE_OPERAND (arg1, 0), 0)
10133 && (rtype = TREE_TYPE (TREE_OPERAND (arg0, 0)),
10134 TYPE_UNSIGNED (rtype))
10135 /* Only create rotates in complete modes. Other cases are not
10136 expanded properly. */
10137 && TYPE_PRECISION (rtype) == GET_MODE_PRECISION (TYPE_MODE (rtype)))
10139 tree tree01, tree11;
10140 enum tree_code code01, code11;
10142 tree01 = TREE_OPERAND (arg0, 1);
10143 tree11 = TREE_OPERAND (arg1, 1);
10144 STRIP_NOPS (tree01);
10145 STRIP_NOPS (tree11);
10146 code01 = TREE_CODE (tree01);
10147 code11 = TREE_CODE (tree11);
10148 if (code01 == INTEGER_CST
10149 && code11 == INTEGER_CST
10150 && TREE_INT_CST_HIGH (tree01) == 0
10151 && TREE_INT_CST_HIGH (tree11) == 0
10152 && ((TREE_INT_CST_LOW (tree01) + TREE_INT_CST_LOW (tree11))
10153 == TYPE_PRECISION (TREE_TYPE (TREE_OPERAND (arg0, 0)))))
10154 return build2 (LROTATE_EXPR, type, TREE_OPERAND (arg0, 0),
10155 code0 == LSHIFT_EXPR ? tree01 : tree11);
10156 else if (code11 == MINUS_EXPR)
10158 tree tree110, tree111;
10159 tree110 = TREE_OPERAND (tree11, 0);
10160 tree111 = TREE_OPERAND (tree11, 1);
10161 STRIP_NOPS (tree110);
10162 STRIP_NOPS (tree111);
10163 if (TREE_CODE (tree110) == INTEGER_CST
10164 && 0 == compare_tree_int (tree110,
10166 (TREE_TYPE (TREE_OPERAND
10168 && operand_equal_p (tree01, tree111, 0))
10169 return build2 ((code0 == LSHIFT_EXPR
10172 type, TREE_OPERAND (arg0, 0), tree01);
10174 else if (code01 == MINUS_EXPR)
10176 tree tree010, tree011;
10177 tree010 = TREE_OPERAND (tree01, 0);
10178 tree011 = TREE_OPERAND (tree01, 1);
10179 STRIP_NOPS (tree010);
10180 STRIP_NOPS (tree011);
10181 if (TREE_CODE (tree010) == INTEGER_CST
10182 && 0 == compare_tree_int (tree010,
10184 (TREE_TYPE (TREE_OPERAND
10186 && operand_equal_p (tree11, tree011, 0))
10187 return build2 ((code0 != LSHIFT_EXPR
10190 type, TREE_OPERAND (arg0, 0), tree11);
10196 /* In most languages, can't associate operations on floats through
10197 parentheses. Rather than remember where the parentheses were, we
10198 don't associate floats at all, unless the user has specified
10199 -fassociative-math.
10200 And, we need to make sure type is not saturating. */
10202 if ((! FLOAT_TYPE_P (type) || flag_associative_math)
10203 && !TYPE_SATURATING (type))
10205 tree var0, con0, lit0, minus_lit0;
10206 tree var1, con1, lit1, minus_lit1;
10209 /* Split both trees into variables, constants, and literals. Then
10210 associate each group together, the constants with literals,
10211 then the result with variables. This increases the chances of
10212 literals being recombined later and of generating relocatable
10213 expressions for the sum of a constant and literal. */
10214 var0 = split_tree (arg0, code, &con0, &lit0, &minus_lit0, 0);
10215 var1 = split_tree (arg1, code, &con1, &lit1, &minus_lit1,
10216 code == MINUS_EXPR);
10218 /* With undefined overflow we can only associate constants
10219 with one variable. */
10220 if (((POINTER_TYPE_P (type) && POINTER_TYPE_OVERFLOW_UNDEFINED)
10221 || (INTEGRAL_TYPE_P (type) && !TYPE_OVERFLOW_WRAPS (type)))
10227 if (TREE_CODE (tmp0) == NEGATE_EXPR)
10228 tmp0 = TREE_OPERAND (tmp0, 0);
10229 if (TREE_CODE (tmp1) == NEGATE_EXPR)
10230 tmp1 = TREE_OPERAND (tmp1, 0);
10231 /* The only case we can still associate with two variables
10232 is if they are the same, modulo negation. */
10233 if (!operand_equal_p (tmp0, tmp1, 0))
10237 /* Only do something if we found more than two objects. Otherwise,
10238 nothing has changed and we risk infinite recursion. */
10240 && (2 < ((var0 != 0) + (var1 != 0)
10241 + (con0 != 0) + (con1 != 0)
10242 + (lit0 != 0) + (lit1 != 0)
10243 + (minus_lit0 != 0) + (minus_lit1 != 0))))
10245 /* Recombine MINUS_EXPR operands by using PLUS_EXPR. */
10246 if (code == MINUS_EXPR)
10249 var0 = associate_trees (var0, var1, code, type);
10250 con0 = associate_trees (con0, con1, code, type);
10251 lit0 = associate_trees (lit0, lit1, code, type);
10252 minus_lit0 = associate_trees (minus_lit0, minus_lit1, code, type);
10254 /* Preserve the MINUS_EXPR if the negative part of the literal is
10255 greater than the positive part. Otherwise, the multiplicative
10256 folding code (i.e extract_muldiv) may be fooled in case
10257 unsigned constants are subtracted, like in the following
10258 example: ((X*2 + 4) - 8U)/2. */
10259 if (minus_lit0 && lit0)
10261 if (TREE_CODE (lit0) == INTEGER_CST
10262 && TREE_CODE (minus_lit0) == INTEGER_CST
10263 && tree_int_cst_lt (lit0, minus_lit0))
10265 minus_lit0 = associate_trees (minus_lit0, lit0,
10271 lit0 = associate_trees (lit0, minus_lit0,
10279 return fold_convert (type,
10280 associate_trees (var0, minus_lit0,
10281 MINUS_EXPR, type));
10284 con0 = associate_trees (con0, minus_lit0,
10286 return fold_convert (type,
10287 associate_trees (var0, con0,
10292 con0 = associate_trees (con0, lit0, code, type);
10293 return fold_convert (type, associate_trees (var0, con0,
10301 /* Pointer simplifications for subtraction, simple reassociations. */
10302 if (POINTER_TYPE_P (TREE_TYPE (arg1)) && POINTER_TYPE_P (TREE_TYPE (arg0)))
10304 /* (PTR0 p+ A) - (PTR1 p+ B) -> (PTR0 - PTR1) + (A - B) */
10305 if (TREE_CODE (arg0) == POINTER_PLUS_EXPR
10306 && TREE_CODE (arg1) == POINTER_PLUS_EXPR)
10308 tree arg00 = fold_convert (type, TREE_OPERAND (arg0, 0));
10309 tree arg01 = fold_convert (type, TREE_OPERAND (arg0, 1));
10310 tree arg10 = fold_convert (type, TREE_OPERAND (arg1, 0));
10311 tree arg11 = fold_convert (type, TREE_OPERAND (arg1, 1));
10312 return fold_build2 (PLUS_EXPR, type,
10313 fold_build2 (MINUS_EXPR, type, arg00, arg10),
10314 fold_build2 (MINUS_EXPR, type, arg01, arg11));
10316 /* (PTR0 p+ A) - PTR1 -> (PTR0 - PTR1) + A, assuming PTR0 - PTR1 simplifies. */
10317 else if (TREE_CODE (arg0) == POINTER_PLUS_EXPR)
10319 tree arg00 = fold_convert (type, TREE_OPERAND (arg0, 0));
10320 tree arg01 = fold_convert (type, TREE_OPERAND (arg0, 1));
10321 tree tmp = fold_binary (MINUS_EXPR, type, arg00, fold_convert (type, arg1));
10323 return fold_build2 (PLUS_EXPR, type, tmp, arg01);
10326 /* A - (-B) -> A + B */
10327 if (TREE_CODE (arg1) == NEGATE_EXPR)
10328 return fold_build2 (PLUS_EXPR, type, op0,
10329 fold_convert (type, TREE_OPERAND (arg1, 0)));
10330 /* (-A) - B -> (-B) - A where B is easily negated and we can swap. */
10331 if (TREE_CODE (arg0) == NEGATE_EXPR
10332 && (FLOAT_TYPE_P (type)
10333 || INTEGRAL_TYPE_P (type))
10334 && negate_expr_p (arg1)
10335 && reorder_operands_p (arg0, arg1))
10336 return fold_build2 (MINUS_EXPR, type,
10337 fold_convert (type, negate_expr (arg1)),
10338 fold_convert (type, TREE_OPERAND (arg0, 0)));
10339 /* Convert -A - 1 to ~A. */
10340 if (INTEGRAL_TYPE_P (type)
10341 && TREE_CODE (arg0) == NEGATE_EXPR
10342 && integer_onep (arg1)
10343 && !TYPE_OVERFLOW_TRAPS (type))
10344 return fold_build1 (BIT_NOT_EXPR, type,
10345 fold_convert (type, TREE_OPERAND (arg0, 0)));
10347 /* Convert -1 - A to ~A. */
10348 if (INTEGRAL_TYPE_P (type)
10349 && integer_all_onesp (arg0))
10350 return fold_build1 (BIT_NOT_EXPR, type, op1);
10353 /* X - (X / CST) * CST is X % CST. */
10354 if (INTEGRAL_TYPE_P (type)
10355 && TREE_CODE (arg1) == MULT_EXPR
10356 && TREE_CODE (TREE_OPERAND (arg1, 0)) == TRUNC_DIV_EXPR
10357 && operand_equal_p (arg0,
10358 TREE_OPERAND (TREE_OPERAND (arg1, 0), 0), 0)
10359 && operand_equal_p (TREE_OPERAND (TREE_OPERAND (arg1, 0), 1),
10360 TREE_OPERAND (arg1, 1), 0))
10361 return fold_convert (type,
10362 fold_build2 (TRUNC_MOD_EXPR, TREE_TYPE (arg0),
10363 arg0, TREE_OPERAND (arg1, 1)));
10365 if (! FLOAT_TYPE_P (type))
10367 if (integer_zerop (arg0))
10368 return negate_expr (fold_convert (type, arg1));
10369 if (integer_zerop (arg1))
10370 return non_lvalue (fold_convert (type, arg0));
10372 /* Fold A - (A & B) into ~B & A. */
10373 if (!TREE_SIDE_EFFECTS (arg0)
10374 && TREE_CODE (arg1) == BIT_AND_EXPR)
10376 if (operand_equal_p (arg0, TREE_OPERAND (arg1, 1), 0))
10378 tree arg10 = fold_convert (type, TREE_OPERAND (arg1, 0));
10379 return fold_build2 (BIT_AND_EXPR, type,
10380 fold_build1 (BIT_NOT_EXPR, type, arg10),
10381 fold_convert (type, arg0));
10383 if (operand_equal_p (arg0, TREE_OPERAND (arg1, 0), 0))
10385 tree arg11 = fold_convert (type, TREE_OPERAND (arg1, 1));
10386 return fold_build2 (BIT_AND_EXPR, type,
10387 fold_build1 (BIT_NOT_EXPR, type, arg11),
10388 fold_convert (type, arg0));
10392 /* Fold (A & ~B) - (A & B) into (A ^ B) - B, where B is
10393 any power of 2 minus 1. */
10394 if (TREE_CODE (arg0) == BIT_AND_EXPR
10395 && TREE_CODE (arg1) == BIT_AND_EXPR
10396 && operand_equal_p (TREE_OPERAND (arg0, 0),
10397 TREE_OPERAND (arg1, 0), 0))
10399 tree mask0 = TREE_OPERAND (arg0, 1);
10400 tree mask1 = TREE_OPERAND (arg1, 1);
10401 tree tem = fold_build1 (BIT_NOT_EXPR, type, mask0);
10403 if (operand_equal_p (tem, mask1, 0))
10405 tem = fold_build2 (BIT_XOR_EXPR, type,
10406 TREE_OPERAND (arg0, 0), mask1);
10407 return fold_build2 (MINUS_EXPR, type, tem, mask1);
10412 /* See if ARG1 is zero and X - ARG1 reduces to X. */
10413 else if (fold_real_zero_addition_p (TREE_TYPE (arg0), arg1, 1))
10414 return non_lvalue (fold_convert (type, arg0));
10416 /* (ARG0 - ARG1) is the same as (-ARG1 + ARG0). So check whether
10417 ARG0 is zero and X + ARG0 reduces to X, since that would mean
10418 (-ARG1 + ARG0) reduces to -ARG1. */
10419 else if (fold_real_zero_addition_p (TREE_TYPE (arg1), arg0, 0))
10420 return negate_expr (fold_convert (type, arg1));
10422 /* Fold __complex__ ( x, 0 ) - __complex__ ( 0, y ) to
10423 __complex__ ( x, -y ). This is not the same for SNaNs or if
10424 signed zeros are involved. */
10425 if (!HONOR_SNANS (TYPE_MODE (TREE_TYPE (arg0)))
10426 && !HONOR_SIGNED_ZEROS (TYPE_MODE (TREE_TYPE (arg0)))
10427 && COMPLEX_FLOAT_TYPE_P (TREE_TYPE (arg0)))
10429 tree rtype = TREE_TYPE (TREE_TYPE (arg0));
10430 tree arg0r = fold_unary (REALPART_EXPR, rtype, arg0);
10431 tree arg0i = fold_unary (IMAGPART_EXPR, rtype, arg0);
10432 bool arg0rz = false, arg0iz = false;
10433 if ((arg0r && (arg0rz = real_zerop (arg0r)))
10434 || (arg0i && (arg0iz = real_zerop (arg0i))))
10436 tree arg1r = fold_unary (REALPART_EXPR, rtype, arg1);
10437 tree arg1i = fold_unary (IMAGPART_EXPR, rtype, arg1);
10438 if (arg0rz && arg1i && real_zerop (arg1i))
10440 tree rp = fold_build1 (NEGATE_EXPR, rtype,
10442 : build1 (REALPART_EXPR, rtype, arg1));
10443 tree ip = arg0i ? arg0i
10444 : build1 (IMAGPART_EXPR, rtype, arg0);
10445 return fold_build2 (COMPLEX_EXPR, type, rp, ip);
10447 else if (arg0iz && arg1r && real_zerop (arg1r))
10449 tree rp = arg0r ? arg0r
10450 : build1 (REALPART_EXPR, rtype, arg0);
10451 tree ip = fold_build1 (NEGATE_EXPR, rtype,
10453 : build1 (IMAGPART_EXPR, rtype, arg1));
10454 return fold_build2 (COMPLEX_EXPR, type, rp, ip);
10459 /* Fold &x - &x. This can happen from &x.foo - &x.
10460 This is unsafe for certain floats even in non-IEEE formats.
10461 In IEEE, it is unsafe because it does wrong for NaNs.
10462 Also note that operand_equal_p is always false if an operand
10465 if ((!FLOAT_TYPE_P (type) || !HONOR_NANS (TYPE_MODE (type)))
10466 && operand_equal_p (arg0, arg1, 0))
10467 return fold_convert (type, integer_zero_node);
10469 /* A - B -> A + (-B) if B is easily negatable. */
10470 if (negate_expr_p (arg1)
10471 && ((FLOAT_TYPE_P (type)
10472 /* Avoid this transformation if B is a positive REAL_CST. */
10473 && (TREE_CODE (arg1) != REAL_CST
10474 || REAL_VALUE_NEGATIVE (TREE_REAL_CST (arg1))))
10475 || INTEGRAL_TYPE_P (type)))
10476 return fold_build2 (PLUS_EXPR, type,
10477 fold_convert (type, arg0),
10478 fold_convert (type, negate_expr (arg1)));
10480 /* Try folding difference of addresses. */
10482 HOST_WIDE_INT diff;
10484 if ((TREE_CODE (arg0) == ADDR_EXPR
10485 || TREE_CODE (arg1) == ADDR_EXPR)
10486 && ptr_difference_const (arg0, arg1, &diff))
10487 return build_int_cst_type (type, diff);
10490 /* Fold &a[i] - &a[j] to i-j. */
10491 if (TREE_CODE (arg0) == ADDR_EXPR
10492 && TREE_CODE (TREE_OPERAND (arg0, 0)) == ARRAY_REF
10493 && TREE_CODE (arg1) == ADDR_EXPR
10494 && TREE_CODE (TREE_OPERAND (arg1, 0)) == ARRAY_REF)
10496 tree aref0 = TREE_OPERAND (arg0, 0);
10497 tree aref1 = TREE_OPERAND (arg1, 0);
10498 if (operand_equal_p (TREE_OPERAND (aref0, 0),
10499 TREE_OPERAND (aref1, 0), 0))
10501 tree op0 = fold_convert (type, TREE_OPERAND (aref0, 1));
10502 tree op1 = fold_convert (type, TREE_OPERAND (aref1, 1));
10503 tree esz = array_ref_element_size (aref0);
10504 tree diff = build2 (MINUS_EXPR, type, op0, op1);
10505 return fold_build2 (MULT_EXPR, type, diff,
10506 fold_convert (type, esz));
10511 if (flag_unsafe_math_optimizations
10512 && (TREE_CODE (arg0) == RDIV_EXPR || TREE_CODE (arg0) == MULT_EXPR)
10513 && (TREE_CODE (arg1) == RDIV_EXPR || TREE_CODE (arg1) == MULT_EXPR)
10514 && (tem = distribute_real_division (code, type, arg0, arg1)))
10517 /* Handle (A1 * C1) - (A2 * C2) with A1, A2 or C1, C2 being the
10518 same or one. Make sure type is not saturating.
10519 fold_plusminus_mult_expr will re-associate. */
10520 if ((TREE_CODE (arg0) == MULT_EXPR
10521 || TREE_CODE (arg1) == MULT_EXPR)
10522 && !TYPE_SATURATING (type)
10523 && (!FLOAT_TYPE_P (type) || flag_associative_math))
10525 tree tem = fold_plusminus_mult_expr (code, type, arg0, arg1);
10533 /* (-A) * (-B) -> A * B */
10534 if (TREE_CODE (arg0) == NEGATE_EXPR && negate_expr_p (arg1))
10535 return fold_build2 (MULT_EXPR, type,
10536 fold_convert (type, TREE_OPERAND (arg0, 0)),
10537 fold_convert (type, negate_expr (arg1)));
10538 if (TREE_CODE (arg1) == NEGATE_EXPR && negate_expr_p (arg0))
10539 return fold_build2 (MULT_EXPR, type,
10540 fold_convert (type, negate_expr (arg0)),
10541 fold_convert (type, TREE_OPERAND (arg1, 0)));
10543 if (! FLOAT_TYPE_P (type))
10545 if (integer_zerop (arg1))
10546 return omit_one_operand (type, arg1, arg0);
10547 if (integer_onep (arg1))
10548 return non_lvalue (fold_convert (type, arg0));
10549 /* Transform x * -1 into -x. Make sure to do the negation
10550 on the original operand with conversions not stripped
10551 because we can only strip non-sign-changing conversions. */
10552 if (integer_all_onesp (arg1))
10553 return fold_convert (type, negate_expr (op0));
10554 /* Transform x * -C into -x * C if x is easily negatable. */
10555 if (TREE_CODE (arg1) == INTEGER_CST
10556 && tree_int_cst_sgn (arg1) == -1
10557 && negate_expr_p (arg0)
10558 && (tem = negate_expr (arg1)) != arg1
10559 && !TREE_OVERFLOW (tem))
10560 return fold_build2 (MULT_EXPR, type,
10561 fold_convert (type, negate_expr (arg0)), tem);
10563 /* (a * (1 << b)) is (a << b) */
10564 if (TREE_CODE (arg1) == LSHIFT_EXPR
10565 && integer_onep (TREE_OPERAND (arg1, 0)))
10566 return fold_build2 (LSHIFT_EXPR, type, op0,
10567 TREE_OPERAND (arg1, 1));
10568 if (TREE_CODE (arg0) == LSHIFT_EXPR
10569 && integer_onep (TREE_OPERAND (arg0, 0)))
10570 return fold_build2 (LSHIFT_EXPR, type, op1,
10571 TREE_OPERAND (arg0, 1));
10573 /* (A + A) * C -> A * 2 * C */
10574 if (TREE_CODE (arg0) == PLUS_EXPR
10575 && TREE_CODE (arg1) == INTEGER_CST
10576 && operand_equal_p (TREE_OPERAND (arg0, 0),
10577 TREE_OPERAND (arg0, 1), 0))
10578 return fold_build2 (MULT_EXPR, type,
10579 omit_one_operand (type, TREE_OPERAND (arg0, 0),
10580 TREE_OPERAND (arg0, 1)),
10581 fold_build2 (MULT_EXPR, type,
10582 build_int_cst (type, 2) , arg1));
10584 strict_overflow_p = false;
10585 if (TREE_CODE (arg1) == INTEGER_CST
10586 && 0 != (tem = extract_muldiv (op0, arg1, code, NULL_TREE,
10587 &strict_overflow_p)))
10589 if (strict_overflow_p)
10590 fold_overflow_warning (("assuming signed overflow does not "
10591 "occur when simplifying "
10593 WARN_STRICT_OVERFLOW_MISC);
10594 return fold_convert (type, tem);
10597 /* Optimize z * conj(z) for integer complex numbers. */
10598 if (TREE_CODE (arg0) == CONJ_EXPR
10599 && operand_equal_p (TREE_OPERAND (arg0, 0), arg1, 0))
10600 return fold_mult_zconjz (type, arg1);
10601 if (TREE_CODE (arg1) == CONJ_EXPR
10602 && operand_equal_p (arg0, TREE_OPERAND (arg1, 0), 0))
10603 return fold_mult_zconjz (type, arg0);
10607 /* Maybe fold x * 0 to 0. The expressions aren't the same
10608 when x is NaN, since x * 0 is also NaN. Nor are they the
10609 same in modes with signed zeros, since multiplying a
10610 negative value by 0 gives -0, not +0. */
10611 if (!HONOR_NANS (TYPE_MODE (TREE_TYPE (arg0)))
10612 && !HONOR_SIGNED_ZEROS (TYPE_MODE (TREE_TYPE (arg0)))
10613 && real_zerop (arg1))
10614 return omit_one_operand (type, arg1, arg0);
10615 /* In IEEE floating point, x*1 is not equivalent to x for snans. */
10616 if (!HONOR_SNANS (TYPE_MODE (TREE_TYPE (arg0)))
10617 && real_onep (arg1))
10618 return non_lvalue (fold_convert (type, arg0));
10620 /* Transform x * -1.0 into -x. */
10621 if (!HONOR_SNANS (TYPE_MODE (TREE_TYPE (arg0)))
10622 && real_minus_onep (arg1))
10623 return fold_convert (type, negate_expr (arg0));
10625 /* Convert (C1/X)*C2 into (C1*C2)/X. This transformation may change
10626 the result for floating point types due to rounding so it is applied
10627 only if -fassociative-math was specify. */
10628 if (flag_associative_math
10629 && TREE_CODE (arg0) == RDIV_EXPR
10630 && TREE_CODE (arg1) == REAL_CST
10631 && TREE_CODE (TREE_OPERAND (arg0, 0)) == REAL_CST)
10633 tree tem = const_binop (MULT_EXPR, TREE_OPERAND (arg0, 0),
10636 return fold_build2 (RDIV_EXPR, type, tem,
10637 TREE_OPERAND (arg0, 1));
10640 /* Strip sign operations from X in X*X, i.e. -Y*-Y -> Y*Y. */
10641 if (operand_equal_p (arg0, arg1, 0))
10643 tree tem = fold_strip_sign_ops (arg0);
10644 if (tem != NULL_TREE)
10646 tem = fold_convert (type, tem);
10647 return fold_build2 (MULT_EXPR, type, tem, tem);
10651 /* Fold z * +-I to __complex__ (-+__imag z, +-__real z).
10652 This is not the same for NaNs or if signed zeros are
10654 if (!HONOR_NANS (TYPE_MODE (TREE_TYPE (arg0)))
10655 && !HONOR_SIGNED_ZEROS (TYPE_MODE (TREE_TYPE (arg0)))
10656 && COMPLEX_FLOAT_TYPE_P (TREE_TYPE (arg0))
10657 && TREE_CODE (arg1) == COMPLEX_CST
10658 && real_zerop (TREE_REALPART (arg1)))
10660 tree rtype = TREE_TYPE (TREE_TYPE (arg0));
10661 if (real_onep (TREE_IMAGPART (arg1)))
10662 return fold_build2 (COMPLEX_EXPR, type,
10663 negate_expr (fold_build1 (IMAGPART_EXPR,
10665 fold_build1 (REALPART_EXPR, rtype, arg0));
10666 else if (real_minus_onep (TREE_IMAGPART (arg1)))
10667 return fold_build2 (COMPLEX_EXPR, type,
10668 fold_build1 (IMAGPART_EXPR, rtype, arg0),
10669 negate_expr (fold_build1 (REALPART_EXPR,
10673 /* Optimize z * conj(z) for floating point complex numbers.
10674 Guarded by flag_unsafe_math_optimizations as non-finite
10675 imaginary components don't produce scalar results. */
10676 if (flag_unsafe_math_optimizations
10677 && TREE_CODE (arg0) == CONJ_EXPR
10678 && operand_equal_p (TREE_OPERAND (arg0, 0), arg1, 0))
10679 return fold_mult_zconjz (type, arg1);
10680 if (flag_unsafe_math_optimizations
10681 && TREE_CODE (arg1) == CONJ_EXPR
10682 && operand_equal_p (arg0, TREE_OPERAND (arg1, 0), 0))
10683 return fold_mult_zconjz (type, arg0);
10685 if (flag_unsafe_math_optimizations)
10687 enum built_in_function fcode0 = builtin_mathfn_code (arg0);
10688 enum built_in_function fcode1 = builtin_mathfn_code (arg1);
10690 /* Optimizations of root(...)*root(...). */
10691 if (fcode0 == fcode1 && BUILTIN_ROOT_P (fcode0))
10694 tree arg00 = CALL_EXPR_ARG (arg0, 0);
10695 tree arg10 = CALL_EXPR_ARG (arg1, 0);
10697 /* Optimize sqrt(x)*sqrt(x) as x. */
10698 if (BUILTIN_SQRT_P (fcode0)
10699 && operand_equal_p (arg00, arg10, 0)
10700 && ! HONOR_SNANS (TYPE_MODE (type)))
10703 /* Optimize root(x)*root(y) as root(x*y). */
10704 rootfn = TREE_OPERAND (CALL_EXPR_FN (arg0), 0);
10705 arg = fold_build2 (MULT_EXPR, type, arg00, arg10);
10706 return build_call_expr (rootfn, 1, arg);
10709 /* Optimize expN(x)*expN(y) as expN(x+y). */
10710 if (fcode0 == fcode1 && BUILTIN_EXPONENT_P (fcode0))
10712 tree expfn = TREE_OPERAND (CALL_EXPR_FN (arg0), 0);
10713 tree arg = fold_build2 (PLUS_EXPR, type,
10714 CALL_EXPR_ARG (arg0, 0),
10715 CALL_EXPR_ARG (arg1, 0));
10716 return build_call_expr (expfn, 1, arg);
10719 /* Optimizations of pow(...)*pow(...). */
10720 if ((fcode0 == BUILT_IN_POW && fcode1 == BUILT_IN_POW)
10721 || (fcode0 == BUILT_IN_POWF && fcode1 == BUILT_IN_POWF)
10722 || (fcode0 == BUILT_IN_POWL && fcode1 == BUILT_IN_POWL))
10724 tree arg00 = CALL_EXPR_ARG (arg0, 0);
10725 tree arg01 = CALL_EXPR_ARG (arg0, 1);
10726 tree arg10 = CALL_EXPR_ARG (arg1, 0);
10727 tree arg11 = CALL_EXPR_ARG (arg1, 1);
10729 /* Optimize pow(x,y)*pow(z,y) as pow(x*z,y). */
10730 if (operand_equal_p (arg01, arg11, 0))
10732 tree powfn = TREE_OPERAND (CALL_EXPR_FN (arg0), 0);
10733 tree arg = fold_build2 (MULT_EXPR, type, arg00, arg10);
10734 return build_call_expr (powfn, 2, arg, arg01);
10737 /* Optimize pow(x,y)*pow(x,z) as pow(x,y+z). */
10738 if (operand_equal_p (arg00, arg10, 0))
10740 tree powfn = TREE_OPERAND (CALL_EXPR_FN (arg0), 0);
10741 tree arg = fold_build2 (PLUS_EXPR, type, arg01, arg11);
10742 return build_call_expr (powfn, 2, arg00, arg);
10746 /* Optimize tan(x)*cos(x) as sin(x). */
10747 if (((fcode0 == BUILT_IN_TAN && fcode1 == BUILT_IN_COS)
10748 || (fcode0 == BUILT_IN_TANF && fcode1 == BUILT_IN_COSF)
10749 || (fcode0 == BUILT_IN_TANL && fcode1 == BUILT_IN_COSL)
10750 || (fcode0 == BUILT_IN_COS && fcode1 == BUILT_IN_TAN)
10751 || (fcode0 == BUILT_IN_COSF && fcode1 == BUILT_IN_TANF)
10752 || (fcode0 == BUILT_IN_COSL && fcode1 == BUILT_IN_TANL))
10753 && operand_equal_p (CALL_EXPR_ARG (arg0, 0),
10754 CALL_EXPR_ARG (arg1, 0), 0))
10756 tree sinfn = mathfn_built_in (type, BUILT_IN_SIN);
10758 if (sinfn != NULL_TREE)
10759 return build_call_expr (sinfn, 1, CALL_EXPR_ARG (arg0, 0));
10762 /* Optimize x*pow(x,c) as pow(x,c+1). */
10763 if (fcode1 == BUILT_IN_POW
10764 || fcode1 == BUILT_IN_POWF
10765 || fcode1 == BUILT_IN_POWL)
10767 tree arg10 = CALL_EXPR_ARG (arg1, 0);
10768 tree arg11 = CALL_EXPR_ARG (arg1, 1);
10769 if (TREE_CODE (arg11) == REAL_CST
10770 && !TREE_OVERFLOW (arg11)
10771 && operand_equal_p (arg0, arg10, 0))
10773 tree powfn = TREE_OPERAND (CALL_EXPR_FN (arg1), 0);
10777 c = TREE_REAL_CST (arg11);
10778 real_arithmetic (&c, PLUS_EXPR, &c, &dconst1);
10779 arg = build_real (type, c);
10780 return build_call_expr (powfn, 2, arg0, arg);
10784 /* Optimize pow(x,c)*x as pow(x,c+1). */
10785 if (fcode0 == BUILT_IN_POW
10786 || fcode0 == BUILT_IN_POWF
10787 || fcode0 == BUILT_IN_POWL)
10789 tree arg00 = CALL_EXPR_ARG (arg0, 0);
10790 tree arg01 = CALL_EXPR_ARG (arg0, 1);
10791 if (TREE_CODE (arg01) == REAL_CST
10792 && !TREE_OVERFLOW (arg01)
10793 && operand_equal_p (arg1, arg00, 0))
10795 tree powfn = TREE_OPERAND (CALL_EXPR_FN (arg0), 0);
10799 c = TREE_REAL_CST (arg01);
10800 real_arithmetic (&c, PLUS_EXPR, &c, &dconst1);
10801 arg = build_real (type, c);
10802 return build_call_expr (powfn, 2, arg1, arg);
10806 /* Optimize x*x as pow(x,2.0), which is expanded as x*x. */
10807 if (optimize_function_for_speed_p (cfun)
10808 && operand_equal_p (arg0, arg1, 0))
10810 tree powfn = mathfn_built_in (type, BUILT_IN_POW);
10814 tree arg = build_real (type, dconst2);
10815 return build_call_expr (powfn, 2, arg0, arg);
10824 if (integer_all_onesp (arg1))
10825 return omit_one_operand (type, arg1, arg0);
10826 if (integer_zerop (arg1))
10827 return non_lvalue (fold_convert (type, arg0));
10828 if (operand_equal_p (arg0, arg1, 0))
10829 return non_lvalue (fold_convert (type, arg0));
10831 /* ~X | X is -1. */
10832 if (TREE_CODE (arg0) == BIT_NOT_EXPR
10833 && operand_equal_p (TREE_OPERAND (arg0, 0), arg1, 0))
10835 t1 = fold_convert (type, integer_zero_node);
10836 t1 = fold_unary (BIT_NOT_EXPR, type, t1);
10837 return omit_one_operand (type, t1, arg1);
10840 /* X | ~X is -1. */
10841 if (TREE_CODE (arg1) == BIT_NOT_EXPR
10842 && operand_equal_p (arg0, TREE_OPERAND (arg1, 0), 0))
10844 t1 = fold_convert (type, integer_zero_node);
10845 t1 = fold_unary (BIT_NOT_EXPR, type, t1);
10846 return omit_one_operand (type, t1, arg0);
10849 /* Canonicalize (X & C1) | C2. */
10850 if (TREE_CODE (arg0) == BIT_AND_EXPR
10851 && TREE_CODE (arg1) == INTEGER_CST
10852 && TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST)
10854 unsigned HOST_WIDE_INT hi1, lo1, hi2, lo2, hi3, lo3, mlo, mhi;
10855 int width = TYPE_PRECISION (type), w;
10856 hi1 = TREE_INT_CST_HIGH (TREE_OPERAND (arg0, 1));
10857 lo1 = TREE_INT_CST_LOW (TREE_OPERAND (arg0, 1));
10858 hi2 = TREE_INT_CST_HIGH (arg1);
10859 lo2 = TREE_INT_CST_LOW (arg1);
10861 /* If (C1&C2) == C1, then (X&C1)|C2 becomes (X,C2). */
10862 if ((hi1 & hi2) == hi1 && (lo1 & lo2) == lo1)
10863 return omit_one_operand (type, arg1, TREE_OPERAND (arg0, 0));
10865 if (width > HOST_BITS_PER_WIDE_INT)
10867 mhi = (unsigned HOST_WIDE_INT) -1
10868 >> (2 * HOST_BITS_PER_WIDE_INT - width);
10874 mlo = (unsigned HOST_WIDE_INT) -1
10875 >> (HOST_BITS_PER_WIDE_INT - width);
10878 /* If (C1|C2) == ~0 then (X&C1)|C2 becomes X|C2. */
10879 if ((~(hi1 | hi2) & mhi) == 0 && (~(lo1 | lo2) & mlo) == 0)
10880 return fold_build2 (BIT_IOR_EXPR, type,
10881 TREE_OPERAND (arg0, 0), arg1);
10883 /* Minimize the number of bits set in C1, i.e. C1 := C1 & ~C2,
10884 unless (C1 & ~C2) | (C2 & C3) for some C3 is a mask of some
10885 mode which allows further optimizations. */
10892 for (w = BITS_PER_UNIT;
10893 w <= width && w <= HOST_BITS_PER_WIDE_INT;
10896 unsigned HOST_WIDE_INT mask
10897 = (unsigned HOST_WIDE_INT) -1 >> (HOST_BITS_PER_WIDE_INT - w);
10898 if (((lo1 | lo2) & mask) == mask
10899 && (lo1 & ~mask) == 0 && hi1 == 0)
10906 if (hi3 != hi1 || lo3 != lo1)
10907 return fold_build2 (BIT_IOR_EXPR, type,
10908 fold_build2 (BIT_AND_EXPR, type,
10909 TREE_OPERAND (arg0, 0),
10910 build_int_cst_wide (type,
10915 /* (X & Y) | Y is (X, Y). */
10916 if (TREE_CODE (arg0) == BIT_AND_EXPR
10917 && operand_equal_p (TREE_OPERAND (arg0, 1), arg1, 0))
10918 return omit_one_operand (type, arg1, TREE_OPERAND (arg0, 0));
10919 /* (X & Y) | X is (Y, X). */
10920 if (TREE_CODE (arg0) == BIT_AND_EXPR
10921 && operand_equal_p (TREE_OPERAND (arg0, 0), arg1, 0)
10922 && reorder_operands_p (TREE_OPERAND (arg0, 1), arg1))
10923 return omit_one_operand (type, arg1, TREE_OPERAND (arg0, 1));
10924 /* X | (X & Y) is (Y, X). */
10925 if (TREE_CODE (arg1) == BIT_AND_EXPR
10926 && operand_equal_p (arg0, TREE_OPERAND (arg1, 0), 0)
10927 && reorder_operands_p (arg0, TREE_OPERAND (arg1, 1)))
10928 return omit_one_operand (type, arg0, TREE_OPERAND (arg1, 1));
10929 /* X | (Y & X) is (Y, X). */
10930 if (TREE_CODE (arg1) == BIT_AND_EXPR
10931 && operand_equal_p (arg0, TREE_OPERAND (arg1, 1), 0)
10932 && reorder_operands_p (arg0, TREE_OPERAND (arg1, 0)))
10933 return omit_one_operand (type, arg0, TREE_OPERAND (arg1, 0));
10935 t1 = distribute_bit_expr (code, type, arg0, arg1);
10936 if (t1 != NULL_TREE)
10939 /* Convert (or (not arg0) (not arg1)) to (not (and (arg0) (arg1))).
10941 This results in more efficient code for machines without a NAND
10942 instruction. Combine will canonicalize to the first form
10943 which will allow use of NAND instructions provided by the
10944 backend if they exist. */
10945 if (TREE_CODE (arg0) == BIT_NOT_EXPR
10946 && TREE_CODE (arg1) == BIT_NOT_EXPR)
10948 return fold_build1 (BIT_NOT_EXPR, type,
10949 build2 (BIT_AND_EXPR, type,
10950 fold_convert (type,
10951 TREE_OPERAND (arg0, 0)),
10952 fold_convert (type,
10953 TREE_OPERAND (arg1, 0))));
10956 /* See if this can be simplified into a rotate first. If that
10957 is unsuccessful continue in the association code. */
10961 if (integer_zerop (arg1))
10962 return non_lvalue (fold_convert (type, arg0));
10963 if (integer_all_onesp (arg1))
10964 return fold_build1 (BIT_NOT_EXPR, type, op0);
10965 if (operand_equal_p (arg0, arg1, 0))
10966 return omit_one_operand (type, integer_zero_node, arg0);
10968 /* ~X ^ X is -1. */
10969 if (TREE_CODE (arg0) == BIT_NOT_EXPR
10970 && operand_equal_p (TREE_OPERAND (arg0, 0), arg1, 0))
10972 t1 = fold_convert (type, integer_zero_node);
10973 t1 = fold_unary (BIT_NOT_EXPR, type, t1);
10974 return omit_one_operand (type, t1, arg1);
10977 /* X ^ ~X is -1. */
10978 if (TREE_CODE (arg1) == BIT_NOT_EXPR
10979 && operand_equal_p (arg0, TREE_OPERAND (arg1, 0), 0))
10981 t1 = fold_convert (type, integer_zero_node);
10982 t1 = fold_unary (BIT_NOT_EXPR, type, t1);
10983 return omit_one_operand (type, t1, arg0);
10986 /* If we are XORing two BIT_AND_EXPR's, both of which are and'ing
10987 with a constant, and the two constants have no bits in common,
10988 we should treat this as a BIT_IOR_EXPR since this may produce more
10989 simplifications. */
10990 if (TREE_CODE (arg0) == BIT_AND_EXPR
10991 && TREE_CODE (arg1) == BIT_AND_EXPR
10992 && TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST
10993 && TREE_CODE (TREE_OPERAND (arg1, 1)) == INTEGER_CST
10994 && integer_zerop (const_binop (BIT_AND_EXPR,
10995 TREE_OPERAND (arg0, 1),
10996 TREE_OPERAND (arg1, 1), 0)))
10998 code = BIT_IOR_EXPR;
11002 /* (X | Y) ^ X -> Y & ~ X*/
11003 if (TREE_CODE (arg0) == BIT_IOR_EXPR
11004 && operand_equal_p (TREE_OPERAND (arg0, 0), arg1, 0))
11006 tree t2 = TREE_OPERAND (arg0, 1);
11007 t1 = fold_build1 (BIT_NOT_EXPR, TREE_TYPE (arg1),
11009 t1 = fold_build2 (BIT_AND_EXPR, type, fold_convert (type, t2),
11010 fold_convert (type, t1));
11014 /* (Y | X) ^ X -> Y & ~ X*/
11015 if (TREE_CODE (arg0) == BIT_IOR_EXPR
11016 && operand_equal_p (TREE_OPERAND (arg0, 1), arg1, 0))
11018 tree t2 = TREE_OPERAND (arg0, 0);
11019 t1 = fold_build1 (BIT_NOT_EXPR, TREE_TYPE (arg1),
11021 t1 = fold_build2 (BIT_AND_EXPR, type, fold_convert (type, t2),
11022 fold_convert (type, t1));
11026 /* X ^ (X | Y) -> Y & ~ X*/
11027 if (TREE_CODE (arg1) == BIT_IOR_EXPR
11028 && operand_equal_p (TREE_OPERAND (arg1, 0), arg0, 0))
11030 tree t2 = TREE_OPERAND (arg1, 1);
11031 t1 = fold_build1 (BIT_NOT_EXPR, TREE_TYPE (arg0),
11033 t1 = fold_build2 (BIT_AND_EXPR, type, fold_convert (type, t2),
11034 fold_convert (type, t1));
11038 /* X ^ (Y | X) -> Y & ~ X*/
11039 if (TREE_CODE (arg1) == BIT_IOR_EXPR
11040 && operand_equal_p (TREE_OPERAND (arg1, 1), arg0, 0))
11042 tree t2 = TREE_OPERAND (arg1, 0);
11043 t1 = fold_build1 (BIT_NOT_EXPR, TREE_TYPE (arg0),
11045 t1 = fold_build2 (BIT_AND_EXPR, type, fold_convert (type, t2),
11046 fold_convert (type, t1));
11050 /* Convert ~X ^ ~Y to X ^ Y. */
11051 if (TREE_CODE (arg0) == BIT_NOT_EXPR
11052 && TREE_CODE (arg1) == BIT_NOT_EXPR)
11053 return fold_build2 (code, type,
11054 fold_convert (type, TREE_OPERAND (arg0, 0)),
11055 fold_convert (type, TREE_OPERAND (arg1, 0)));
11057 /* Convert ~X ^ C to X ^ ~C. */
11058 if (TREE_CODE (arg0) == BIT_NOT_EXPR
11059 && TREE_CODE (arg1) == INTEGER_CST)
11060 return fold_build2 (code, type,
11061 fold_convert (type, TREE_OPERAND (arg0, 0)),
11062 fold_build1 (BIT_NOT_EXPR, type, arg1));
11064 /* Fold (X & 1) ^ 1 as (X & 1) == 0. */
11065 if (TREE_CODE (arg0) == BIT_AND_EXPR
11066 && integer_onep (TREE_OPERAND (arg0, 1))
11067 && integer_onep (arg1))
11068 return fold_build2 (EQ_EXPR, type, arg0,
11069 build_int_cst (TREE_TYPE (arg0), 0));
11071 /* Fold (X & Y) ^ Y as ~X & Y. */
11072 if (TREE_CODE (arg0) == BIT_AND_EXPR
11073 && operand_equal_p (TREE_OPERAND (arg0, 1), arg1, 0))
11075 tem = fold_convert (type, TREE_OPERAND (arg0, 0));
11076 return fold_build2 (BIT_AND_EXPR, type,
11077 fold_build1 (BIT_NOT_EXPR, type, tem),
11078 fold_convert (type, arg1));
11080 /* Fold (X & Y) ^ X as ~Y & X. */
11081 if (TREE_CODE (arg0) == BIT_AND_EXPR
11082 && operand_equal_p (TREE_OPERAND (arg0, 0), arg1, 0)
11083 && reorder_operands_p (TREE_OPERAND (arg0, 1), arg1))
11085 tem = fold_convert (type, TREE_OPERAND (arg0, 1));
11086 return fold_build2 (BIT_AND_EXPR, type,
11087 fold_build1 (BIT_NOT_EXPR, type, tem),
11088 fold_convert (type, arg1));
11090 /* Fold X ^ (X & Y) as X & ~Y. */
11091 if (TREE_CODE (arg1) == BIT_AND_EXPR
11092 && operand_equal_p (arg0, TREE_OPERAND (arg1, 0), 0))
11094 tem = fold_convert (type, TREE_OPERAND (arg1, 1));
11095 return fold_build2 (BIT_AND_EXPR, type,
11096 fold_convert (type, arg0),
11097 fold_build1 (BIT_NOT_EXPR, type, tem));
11099 /* Fold X ^ (Y & X) as ~Y & X. */
11100 if (TREE_CODE (arg1) == BIT_AND_EXPR
11101 && operand_equal_p (arg0, TREE_OPERAND (arg1, 1), 0)
11102 && reorder_operands_p (arg0, TREE_OPERAND (arg1, 0)))
11104 tem = fold_convert (type, TREE_OPERAND (arg1, 0));
11105 return fold_build2 (BIT_AND_EXPR, type,
11106 fold_build1 (BIT_NOT_EXPR, type, tem),
11107 fold_convert (type, arg0));
11110 /* See if this can be simplified into a rotate first. If that
11111 is unsuccessful continue in the association code. */
11115 if (integer_all_onesp (arg1))
11116 return non_lvalue (fold_convert (type, arg0));
11117 if (integer_zerop (arg1))
11118 return omit_one_operand (type, arg1, arg0);
11119 if (operand_equal_p (arg0, arg1, 0))
11120 return non_lvalue (fold_convert (type, arg0));
11122 /* ~X & X is always zero. */
11123 if (TREE_CODE (arg0) == BIT_NOT_EXPR
11124 && operand_equal_p (TREE_OPERAND (arg0, 0), arg1, 0))
11125 return omit_one_operand (type, integer_zero_node, arg1);
11127 /* X & ~X is always zero. */
11128 if (TREE_CODE (arg1) == BIT_NOT_EXPR
11129 && operand_equal_p (arg0, TREE_OPERAND (arg1, 0), 0))
11130 return omit_one_operand (type, integer_zero_node, arg0);
11132 /* Canonicalize (X | C1) & C2 as (X & C2) | (C1 & C2). */
11133 if (TREE_CODE (arg0) == BIT_IOR_EXPR
11134 && TREE_CODE (arg1) == INTEGER_CST
11135 && TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST)
11137 tree tmp1 = fold_convert (type, arg1);
11138 tree tmp2 = fold_convert (type, TREE_OPERAND (arg0, 0));
11139 tree tmp3 = fold_convert (type, TREE_OPERAND (arg0, 1));
11140 tmp2 = fold_build2 (BIT_AND_EXPR, type, tmp2, tmp1);
11141 tmp3 = fold_build2 (BIT_AND_EXPR, type, tmp3, tmp1);
11142 return fold_convert (type,
11143 fold_build2 (BIT_IOR_EXPR, type, tmp2, tmp3));
11146 /* (X | Y) & Y is (X, Y). */
11147 if (TREE_CODE (arg0) == BIT_IOR_EXPR
11148 && operand_equal_p (TREE_OPERAND (arg0, 1), arg1, 0))
11149 return omit_one_operand (type, arg1, TREE_OPERAND (arg0, 0));
11150 /* (X | Y) & X is (Y, X). */
11151 if (TREE_CODE (arg0) == BIT_IOR_EXPR
11152 && operand_equal_p (TREE_OPERAND (arg0, 0), arg1, 0)
11153 && reorder_operands_p (TREE_OPERAND (arg0, 1), arg1))
11154 return omit_one_operand (type, arg1, TREE_OPERAND (arg0, 1));
11155 /* X & (X | Y) is (Y, X). */
11156 if (TREE_CODE (arg1) == BIT_IOR_EXPR
11157 && operand_equal_p (arg0, TREE_OPERAND (arg1, 0), 0)
11158 && reorder_operands_p (arg0, TREE_OPERAND (arg1, 1)))
11159 return omit_one_operand (type, arg0, TREE_OPERAND (arg1, 1));
11160 /* X & (Y | X) is (Y, X). */
11161 if (TREE_CODE (arg1) == BIT_IOR_EXPR
11162 && operand_equal_p (arg0, TREE_OPERAND (arg1, 1), 0)
11163 && reorder_operands_p (arg0, TREE_OPERAND (arg1, 0)))
11164 return omit_one_operand (type, arg0, TREE_OPERAND (arg1, 0));
11166 /* Fold (X ^ 1) & 1 as (X & 1) == 0. */
11167 if (TREE_CODE (arg0) == BIT_XOR_EXPR
11168 && integer_onep (TREE_OPERAND (arg0, 1))
11169 && integer_onep (arg1))
11171 tem = TREE_OPERAND (arg0, 0);
11172 return fold_build2 (EQ_EXPR, type,
11173 fold_build2 (BIT_AND_EXPR, TREE_TYPE (tem), tem,
11174 build_int_cst (TREE_TYPE (tem), 1)),
11175 build_int_cst (TREE_TYPE (tem), 0));
11177 /* Fold ~X & 1 as (X & 1) == 0. */
11178 if (TREE_CODE (arg0) == BIT_NOT_EXPR
11179 && integer_onep (arg1))
11181 tem = TREE_OPERAND (arg0, 0);
11182 return fold_build2 (EQ_EXPR, type,
11183 fold_build2 (BIT_AND_EXPR, TREE_TYPE (tem), tem,
11184 build_int_cst (TREE_TYPE (tem), 1)),
11185 build_int_cst (TREE_TYPE (tem), 0));
11188 /* Fold (X ^ Y) & Y as ~X & Y. */
11189 if (TREE_CODE (arg0) == BIT_XOR_EXPR
11190 && operand_equal_p (TREE_OPERAND (arg0, 1), arg1, 0))
11192 tem = fold_convert (type, TREE_OPERAND (arg0, 0));
11193 return fold_build2 (BIT_AND_EXPR, type,
11194 fold_build1 (BIT_NOT_EXPR, type, tem),
11195 fold_convert (type, arg1));
11197 /* Fold (X ^ Y) & X as ~Y & X. */
11198 if (TREE_CODE (arg0) == BIT_XOR_EXPR
11199 && operand_equal_p (TREE_OPERAND (arg0, 0), arg1, 0)
11200 && reorder_operands_p (TREE_OPERAND (arg0, 1), arg1))
11202 tem = fold_convert (type, TREE_OPERAND (arg0, 1));
11203 return fold_build2 (BIT_AND_EXPR, type,
11204 fold_build1 (BIT_NOT_EXPR, type, tem),
11205 fold_convert (type, arg1));
11207 /* Fold X & (X ^ Y) as X & ~Y. */
11208 if (TREE_CODE (arg1) == BIT_XOR_EXPR
11209 && operand_equal_p (arg0, TREE_OPERAND (arg1, 0), 0))
11211 tem = fold_convert (type, TREE_OPERAND (arg1, 1));
11212 return fold_build2 (BIT_AND_EXPR, type,
11213 fold_convert (type, arg0),
11214 fold_build1 (BIT_NOT_EXPR, type, tem));
11216 /* Fold X & (Y ^ X) as ~Y & X. */
11217 if (TREE_CODE (arg1) == BIT_XOR_EXPR
11218 && operand_equal_p (arg0, TREE_OPERAND (arg1, 1), 0)
11219 && reorder_operands_p (arg0, TREE_OPERAND (arg1, 0)))
11221 tem = fold_convert (type, TREE_OPERAND (arg1, 0));
11222 return fold_build2 (BIT_AND_EXPR, type,
11223 fold_build1 (BIT_NOT_EXPR, type, tem),
11224 fold_convert (type, arg0));
11227 t1 = distribute_bit_expr (code, type, arg0, arg1);
11228 if (t1 != NULL_TREE)
11230 /* Simplify ((int)c & 0377) into (int)c, if c is unsigned char. */
11231 if (TREE_CODE (arg1) == INTEGER_CST && TREE_CODE (arg0) == NOP_EXPR
11232 && TYPE_UNSIGNED (TREE_TYPE (TREE_OPERAND (arg0, 0))))
11235 = TYPE_PRECISION (TREE_TYPE (TREE_OPERAND (arg0, 0)));
11237 if (prec < BITS_PER_WORD && prec < HOST_BITS_PER_WIDE_INT
11238 && (~TREE_INT_CST_LOW (arg1)
11239 & (((HOST_WIDE_INT) 1 << prec) - 1)) == 0)
11240 return fold_convert (type, TREE_OPERAND (arg0, 0));
11243 /* Convert (and (not arg0) (not arg1)) to (not (or (arg0) (arg1))).
11245 This results in more efficient code for machines without a NOR
11246 instruction. Combine will canonicalize to the first form
11247 which will allow use of NOR instructions provided by the
11248 backend if they exist. */
11249 if (TREE_CODE (arg0) == BIT_NOT_EXPR
11250 && TREE_CODE (arg1) == BIT_NOT_EXPR)
11252 return fold_build1 (BIT_NOT_EXPR, type,
11253 build2 (BIT_IOR_EXPR, type,
11254 fold_convert (type,
11255 TREE_OPERAND (arg0, 0)),
11256 fold_convert (type,
11257 TREE_OPERAND (arg1, 0))));
11260 /* If arg0 is derived from the address of an object or function, we may
11261 be able to fold this expression using the object or function's
11263 if (POINTER_TYPE_P (TREE_TYPE (arg0)) && host_integerp (arg1, 1))
11265 unsigned HOST_WIDE_INT modulus, residue;
11266 unsigned HOST_WIDE_INT low = TREE_INT_CST_LOW (arg1);
11268 modulus = get_pointer_modulus_and_residue (arg0, &residue);
11270 /* This works because modulus is a power of 2. If this weren't the
11271 case, we'd have to replace it by its greatest power-of-2
11272 divisor: modulus & -modulus. */
11274 return build_int_cst (type, residue & low);
11277 /* Fold (X << C1) & C2 into (X << C1) & (C2 | ((1 << C1) - 1))
11278 (X >> C1) & C2 into (X >> C1) & (C2 | ~((type) -1 >> C1))
11279 if the new mask might be further optimized. */
11280 if ((TREE_CODE (arg0) == LSHIFT_EXPR
11281 || TREE_CODE (arg0) == RSHIFT_EXPR)
11282 && host_integerp (TREE_OPERAND (arg0, 1), 1)
11283 && host_integerp (arg1, TYPE_UNSIGNED (TREE_TYPE (arg1)))
11284 && tree_low_cst (TREE_OPERAND (arg0, 1), 1)
11285 < TYPE_PRECISION (TREE_TYPE (arg0))
11286 && TYPE_PRECISION (TREE_TYPE (arg0)) <= HOST_BITS_PER_WIDE_INT
11287 && tree_low_cst (TREE_OPERAND (arg0, 1), 1) > 0)
11289 unsigned int shiftc = tree_low_cst (TREE_OPERAND (arg0, 1), 1);
11290 unsigned HOST_WIDE_INT mask
11291 = tree_low_cst (arg1, TYPE_UNSIGNED (TREE_TYPE (arg1)));
11292 unsigned HOST_WIDE_INT newmask, zerobits = 0;
11293 tree shift_type = TREE_TYPE (arg0);
11295 if (TREE_CODE (arg0) == LSHIFT_EXPR)
11296 zerobits = ((((unsigned HOST_WIDE_INT) 1) << shiftc) - 1);
11297 else if (TREE_CODE (arg0) == RSHIFT_EXPR
11298 && TYPE_PRECISION (TREE_TYPE (arg0))
11299 == GET_MODE_BITSIZE (TYPE_MODE (TREE_TYPE (arg0))))
11301 unsigned int prec = TYPE_PRECISION (TREE_TYPE (arg0));
11302 tree arg00 = TREE_OPERAND (arg0, 0);
11303 /* See if more bits can be proven as zero because of
11305 if (TREE_CODE (arg00) == NOP_EXPR
11306 && TYPE_UNSIGNED (TREE_TYPE (TREE_OPERAND (arg00, 0))))
11308 tree inner_type = TREE_TYPE (TREE_OPERAND (arg00, 0));
11309 if (TYPE_PRECISION (inner_type)
11310 == GET_MODE_BITSIZE (TYPE_MODE (inner_type))
11311 && TYPE_PRECISION (inner_type) < prec)
11313 prec = TYPE_PRECISION (inner_type);
11314 /* See if we can shorten the right shift. */
11316 shift_type = inner_type;
11319 zerobits = ~(unsigned HOST_WIDE_INT) 0;
11320 zerobits >>= HOST_BITS_PER_WIDE_INT - shiftc;
11321 zerobits <<= prec - shiftc;
11322 /* For arithmetic shift if sign bit could be set, zerobits
11323 can contain actually sign bits, so no transformation is
11324 possible, unless MASK masks them all away. In that
11325 case the shift needs to be converted into logical shift. */
11326 if (!TYPE_UNSIGNED (TREE_TYPE (arg0))
11327 && prec == TYPE_PRECISION (TREE_TYPE (arg0)))
11329 if ((mask & zerobits) == 0)
11330 shift_type = unsigned_type_for (TREE_TYPE (arg0));
11336 /* ((X << 16) & 0xff00) is (X, 0). */
11337 if ((mask & zerobits) == mask)
11338 return omit_one_operand (type, build_int_cst (type, 0), arg0);
11340 newmask = mask | zerobits;
11341 if (newmask != mask && (newmask & (newmask + 1)) == 0)
11345 /* Only do the transformation if NEWMASK is some integer
11347 for (prec = BITS_PER_UNIT;
11348 prec < HOST_BITS_PER_WIDE_INT; prec <<= 1)
11349 if (newmask == (((unsigned HOST_WIDE_INT) 1) << prec) - 1)
11351 if (prec < HOST_BITS_PER_WIDE_INT
11352 || newmask == ~(unsigned HOST_WIDE_INT) 0)
11354 if (shift_type != TREE_TYPE (arg0))
11356 tem = fold_build2 (TREE_CODE (arg0), shift_type,
11357 fold_convert (shift_type,
11358 TREE_OPERAND (arg0, 0)),
11359 TREE_OPERAND (arg0, 1));
11360 tem = fold_convert (type, tem);
11364 return fold_build2 (BIT_AND_EXPR, type, tem,
11365 build_int_cst_type (TREE_TYPE (op1),
11374 /* Don't touch a floating-point divide by zero unless the mode
11375 of the constant can represent infinity. */
11376 if (TREE_CODE (arg1) == REAL_CST
11377 && !MODE_HAS_INFINITIES (TYPE_MODE (TREE_TYPE (arg1)))
11378 && real_zerop (arg1))
11381 /* Optimize A / A to 1.0 if we don't care about
11382 NaNs or Infinities. Skip the transformation
11383 for non-real operands. */
11384 if (SCALAR_FLOAT_TYPE_P (TREE_TYPE (arg0))
11385 && ! HONOR_NANS (TYPE_MODE (TREE_TYPE (arg0)))
11386 && ! HONOR_INFINITIES (TYPE_MODE (TREE_TYPE (arg0)))
11387 && operand_equal_p (arg0, arg1, 0))
11389 tree r = build_real (TREE_TYPE (arg0), dconst1);
11391 return omit_two_operands (type, r, arg0, arg1);
11394 /* The complex version of the above A / A optimization. */
11395 if (COMPLEX_FLOAT_TYPE_P (TREE_TYPE (arg0))
11396 && operand_equal_p (arg0, arg1, 0))
11398 tree elem_type = TREE_TYPE (TREE_TYPE (arg0));
11399 if (! HONOR_NANS (TYPE_MODE (elem_type))
11400 && ! HONOR_INFINITIES (TYPE_MODE (elem_type)))
11402 tree r = build_real (elem_type, dconst1);
11403 /* omit_two_operands will call fold_convert for us. */
11404 return omit_two_operands (type, r, arg0, arg1);
11408 /* (-A) / (-B) -> A / B */
11409 if (TREE_CODE (arg0) == NEGATE_EXPR && negate_expr_p (arg1))
11410 return fold_build2 (RDIV_EXPR, type,
11411 TREE_OPERAND (arg0, 0),
11412 negate_expr (arg1));
11413 if (TREE_CODE (arg1) == NEGATE_EXPR && negate_expr_p (arg0))
11414 return fold_build2 (RDIV_EXPR, type,
11415 negate_expr (arg0),
11416 TREE_OPERAND (arg1, 0));
11418 /* In IEEE floating point, x/1 is not equivalent to x for snans. */
11419 if (!HONOR_SNANS (TYPE_MODE (TREE_TYPE (arg0)))
11420 && real_onep (arg1))
11421 return non_lvalue (fold_convert (type, arg0));
11423 /* In IEEE floating point, x/-1 is not equivalent to -x for snans. */
11424 if (!HONOR_SNANS (TYPE_MODE (TREE_TYPE (arg0)))
11425 && real_minus_onep (arg1))
11426 return non_lvalue (fold_convert (type, negate_expr (arg0)));
11428 /* If ARG1 is a constant, we can convert this to a multiply by the
11429 reciprocal. This does not have the same rounding properties,
11430 so only do this if -freciprocal-math. We can actually
11431 always safely do it if ARG1 is a power of two, but it's hard to
11432 tell if it is or not in a portable manner. */
11433 if (TREE_CODE (arg1) == REAL_CST)
11435 if (flag_reciprocal_math
11436 && 0 != (tem = const_binop (code, build_real (type, dconst1),
11438 return fold_build2 (MULT_EXPR, type, arg0, tem);
11439 /* Find the reciprocal if optimizing and the result is exact. */
11443 r = TREE_REAL_CST (arg1);
11444 if (exact_real_inverse (TYPE_MODE(TREE_TYPE(arg0)), &r))
11446 tem = build_real (type, r);
11447 return fold_build2 (MULT_EXPR, type,
11448 fold_convert (type, arg0), tem);
11452 /* Convert A/B/C to A/(B*C). */
11453 if (flag_reciprocal_math
11454 && TREE_CODE (arg0) == RDIV_EXPR)
11455 return fold_build2 (RDIV_EXPR, type, TREE_OPERAND (arg0, 0),
11456 fold_build2 (MULT_EXPR, type,
11457 TREE_OPERAND (arg0, 1), arg1));
11459 /* Convert A/(B/C) to (A/B)*C. */
11460 if (flag_reciprocal_math
11461 && TREE_CODE (arg1) == RDIV_EXPR)
11462 return fold_build2 (MULT_EXPR, type,
11463 fold_build2 (RDIV_EXPR, type, arg0,
11464 TREE_OPERAND (arg1, 0)),
11465 TREE_OPERAND (arg1, 1));
11467 /* Convert C1/(X*C2) into (C1/C2)/X. */
11468 if (flag_reciprocal_math
11469 && TREE_CODE (arg1) == MULT_EXPR
11470 && TREE_CODE (arg0) == REAL_CST
11471 && TREE_CODE (TREE_OPERAND (arg1, 1)) == REAL_CST)
11473 tree tem = const_binop (RDIV_EXPR, arg0,
11474 TREE_OPERAND (arg1, 1), 0);
11476 return fold_build2 (RDIV_EXPR, type, tem,
11477 TREE_OPERAND (arg1, 0));
11480 if (flag_unsafe_math_optimizations)
11482 enum built_in_function fcode0 = builtin_mathfn_code (arg0);
11483 enum built_in_function fcode1 = builtin_mathfn_code (arg1);
11485 /* Optimize sin(x)/cos(x) as tan(x). */
11486 if (((fcode0 == BUILT_IN_SIN && fcode1 == BUILT_IN_COS)
11487 || (fcode0 == BUILT_IN_SINF && fcode1 == BUILT_IN_COSF)
11488 || (fcode0 == BUILT_IN_SINL && fcode1 == BUILT_IN_COSL))
11489 && operand_equal_p (CALL_EXPR_ARG (arg0, 0),
11490 CALL_EXPR_ARG (arg1, 0), 0))
11492 tree tanfn = mathfn_built_in (type, BUILT_IN_TAN);
11494 if (tanfn != NULL_TREE)
11495 return build_call_expr (tanfn, 1, CALL_EXPR_ARG (arg0, 0));
11498 /* Optimize cos(x)/sin(x) as 1.0/tan(x). */
11499 if (((fcode0 == BUILT_IN_COS && fcode1 == BUILT_IN_SIN)
11500 || (fcode0 == BUILT_IN_COSF && fcode1 == BUILT_IN_SINF)
11501 || (fcode0 == BUILT_IN_COSL && fcode1 == BUILT_IN_SINL))
11502 && operand_equal_p (CALL_EXPR_ARG (arg0, 0),
11503 CALL_EXPR_ARG (arg1, 0), 0))
11505 tree tanfn = mathfn_built_in (type, BUILT_IN_TAN);
11507 if (tanfn != NULL_TREE)
11509 tree tmp = build_call_expr (tanfn, 1, CALL_EXPR_ARG (arg0, 0));
11510 return fold_build2 (RDIV_EXPR, type,
11511 build_real (type, dconst1), tmp);
11515 /* Optimize sin(x)/tan(x) as cos(x) if we don't care about
11516 NaNs or Infinities. */
11517 if (((fcode0 == BUILT_IN_SIN && fcode1 == BUILT_IN_TAN)
11518 || (fcode0 == BUILT_IN_SINF && fcode1 == BUILT_IN_TANF)
11519 || (fcode0 == BUILT_IN_SINL && fcode1 == BUILT_IN_TANL)))
11521 tree arg00 = CALL_EXPR_ARG (arg0, 0);
11522 tree arg01 = CALL_EXPR_ARG (arg1, 0);
11524 if (! HONOR_NANS (TYPE_MODE (TREE_TYPE (arg00)))
11525 && ! HONOR_INFINITIES (TYPE_MODE (TREE_TYPE (arg00)))
11526 && operand_equal_p (arg00, arg01, 0))
11528 tree cosfn = mathfn_built_in (type, BUILT_IN_COS);
11530 if (cosfn != NULL_TREE)
11531 return build_call_expr (cosfn, 1, arg00);
11535 /* Optimize tan(x)/sin(x) as 1.0/cos(x) if we don't care about
11536 NaNs or Infinities. */
11537 if (((fcode0 == BUILT_IN_TAN && fcode1 == BUILT_IN_SIN)
11538 || (fcode0 == BUILT_IN_TANF && fcode1 == BUILT_IN_SINF)
11539 || (fcode0 == BUILT_IN_TANL && fcode1 == BUILT_IN_SINL)))
11541 tree arg00 = CALL_EXPR_ARG (arg0, 0);
11542 tree arg01 = CALL_EXPR_ARG (arg1, 0);
11544 if (! HONOR_NANS (TYPE_MODE (TREE_TYPE (arg00)))
11545 && ! HONOR_INFINITIES (TYPE_MODE (TREE_TYPE (arg00)))
11546 && operand_equal_p (arg00, arg01, 0))
11548 tree cosfn = mathfn_built_in (type, BUILT_IN_COS);
11550 if (cosfn != NULL_TREE)
11552 tree tmp = build_call_expr (cosfn, 1, arg00);
11553 return fold_build2 (RDIV_EXPR, type,
11554 build_real (type, dconst1),
11560 /* Optimize pow(x,c)/x as pow(x,c-1). */
11561 if (fcode0 == BUILT_IN_POW
11562 || fcode0 == BUILT_IN_POWF
11563 || fcode0 == BUILT_IN_POWL)
11565 tree arg00 = CALL_EXPR_ARG (arg0, 0);
11566 tree arg01 = CALL_EXPR_ARG (arg0, 1);
11567 if (TREE_CODE (arg01) == REAL_CST
11568 && !TREE_OVERFLOW (arg01)
11569 && operand_equal_p (arg1, arg00, 0))
11571 tree powfn = TREE_OPERAND (CALL_EXPR_FN (arg0), 0);
11575 c = TREE_REAL_CST (arg01);
11576 real_arithmetic (&c, MINUS_EXPR, &c, &dconst1);
11577 arg = build_real (type, c);
11578 return build_call_expr (powfn, 2, arg1, arg);
11582 /* Optimize a/root(b/c) into a*root(c/b). */
11583 if (BUILTIN_ROOT_P (fcode1))
11585 tree rootarg = CALL_EXPR_ARG (arg1, 0);
11587 if (TREE_CODE (rootarg) == RDIV_EXPR)
11589 tree rootfn = TREE_OPERAND (CALL_EXPR_FN (arg1), 0);
11590 tree b = TREE_OPERAND (rootarg, 0);
11591 tree c = TREE_OPERAND (rootarg, 1);
11593 tree tmp = fold_build2 (RDIV_EXPR, type, c, b);
11595 tmp = build_call_expr (rootfn, 1, tmp);
11596 return fold_build2 (MULT_EXPR, type, arg0, tmp);
11600 /* Optimize x/expN(y) into x*expN(-y). */
11601 if (BUILTIN_EXPONENT_P (fcode1))
11603 tree expfn = TREE_OPERAND (CALL_EXPR_FN (arg1), 0);
11604 tree arg = negate_expr (CALL_EXPR_ARG (arg1, 0));
11605 arg1 = build_call_expr (expfn, 1, fold_convert (type, arg));
11606 return fold_build2 (MULT_EXPR, type, arg0, arg1);
11609 /* Optimize x/pow(y,z) into x*pow(y,-z). */
11610 if (fcode1 == BUILT_IN_POW
11611 || fcode1 == BUILT_IN_POWF
11612 || fcode1 == BUILT_IN_POWL)
11614 tree powfn = TREE_OPERAND (CALL_EXPR_FN (arg1), 0);
11615 tree arg10 = CALL_EXPR_ARG (arg1, 0);
11616 tree arg11 = CALL_EXPR_ARG (arg1, 1);
11617 tree neg11 = fold_convert (type, negate_expr (arg11));
11618 arg1 = build_call_expr (powfn, 2, arg10, neg11);
11619 return fold_build2 (MULT_EXPR, type, arg0, arg1);
11624 case TRUNC_DIV_EXPR:
11625 case FLOOR_DIV_EXPR:
11626 /* Simplify A / (B << N) where A and B are positive and B is
11627 a power of 2, to A >> (N + log2(B)). */
11628 strict_overflow_p = false;
11629 if (TREE_CODE (arg1) == LSHIFT_EXPR
11630 && (TYPE_UNSIGNED (type)
11631 || tree_expr_nonnegative_warnv_p (op0, &strict_overflow_p)))
11633 tree sval = TREE_OPERAND (arg1, 0);
11634 if (integer_pow2p (sval) && tree_int_cst_sgn (sval) > 0)
11636 tree sh_cnt = TREE_OPERAND (arg1, 1);
11637 unsigned long pow2 = exact_log2 (TREE_INT_CST_LOW (sval));
11639 if (strict_overflow_p)
11640 fold_overflow_warning (("assuming signed overflow does not "
11641 "occur when simplifying A / (B << N)"),
11642 WARN_STRICT_OVERFLOW_MISC);
11644 sh_cnt = fold_build2 (PLUS_EXPR, TREE_TYPE (sh_cnt),
11645 sh_cnt, build_int_cst (NULL_TREE, pow2));
11646 return fold_build2 (RSHIFT_EXPR, type,
11647 fold_convert (type, arg0), sh_cnt);
11651 /* For unsigned integral types, FLOOR_DIV_EXPR is the same as
11652 TRUNC_DIV_EXPR. Rewrite into the latter in this case. */
11653 if (INTEGRAL_TYPE_P (type)
11654 && TYPE_UNSIGNED (type)
11655 && code == FLOOR_DIV_EXPR)
11656 return fold_build2 (TRUNC_DIV_EXPR, type, op0, op1);
11660 case ROUND_DIV_EXPR:
11661 case CEIL_DIV_EXPR:
11662 case EXACT_DIV_EXPR:
11663 if (integer_onep (arg1))
11664 return non_lvalue (fold_convert (type, arg0));
11665 if (integer_zerop (arg1))
11667 /* X / -1 is -X. */
11668 if (!TYPE_UNSIGNED (type)
11669 && TREE_CODE (arg1) == INTEGER_CST
11670 && TREE_INT_CST_LOW (arg1) == (unsigned HOST_WIDE_INT) -1
11671 && TREE_INT_CST_HIGH (arg1) == -1)
11672 return fold_convert (type, negate_expr (arg0));
11674 /* Convert -A / -B to A / B when the type is signed and overflow is
11676 if ((!INTEGRAL_TYPE_P (type) || TYPE_OVERFLOW_UNDEFINED (type))
11677 && TREE_CODE (arg0) == NEGATE_EXPR
11678 && negate_expr_p (arg1))
11680 if (INTEGRAL_TYPE_P (type))
11681 fold_overflow_warning (("assuming signed overflow does not occur "
11682 "when distributing negation across "
11684 WARN_STRICT_OVERFLOW_MISC);
11685 return fold_build2 (code, type,
11686 fold_convert (type, TREE_OPERAND (arg0, 0)),
11687 fold_convert (type, negate_expr (arg1)));
11689 if ((!INTEGRAL_TYPE_P (type) || TYPE_OVERFLOW_UNDEFINED (type))
11690 && TREE_CODE (arg1) == NEGATE_EXPR
11691 && negate_expr_p (arg0))
11693 if (INTEGRAL_TYPE_P (type))
11694 fold_overflow_warning (("assuming signed overflow does not occur "
11695 "when distributing negation across "
11697 WARN_STRICT_OVERFLOW_MISC);
11698 return fold_build2 (code, type,
11699 fold_convert (type, negate_expr (arg0)),
11700 fold_convert (type, TREE_OPERAND (arg1, 0)));
11703 /* If arg0 is a multiple of arg1, then rewrite to the fastest div
11704 operation, EXACT_DIV_EXPR.
11706 Note that only CEIL_DIV_EXPR and FLOOR_DIV_EXPR are rewritten now.
11707 At one time others generated faster code, it's not clear if they do
11708 after the last round to changes to the DIV code in expmed.c. */
11709 if ((code == CEIL_DIV_EXPR || code == FLOOR_DIV_EXPR)
11710 && multiple_of_p (type, arg0, arg1))
11711 return fold_build2 (EXACT_DIV_EXPR, type, arg0, arg1);
11713 strict_overflow_p = false;
11714 if (TREE_CODE (arg1) == INTEGER_CST
11715 && 0 != (tem = extract_muldiv (op0, arg1, code, NULL_TREE,
11716 &strict_overflow_p)))
11718 if (strict_overflow_p)
11719 fold_overflow_warning (("assuming signed overflow does not occur "
11720 "when simplifying division"),
11721 WARN_STRICT_OVERFLOW_MISC);
11722 return fold_convert (type, tem);
11727 case CEIL_MOD_EXPR:
11728 case FLOOR_MOD_EXPR:
11729 case ROUND_MOD_EXPR:
11730 case TRUNC_MOD_EXPR:
11731 /* X % 1 is always zero, but be sure to preserve any side
11733 if (integer_onep (arg1))
11734 return omit_one_operand (type, integer_zero_node, arg0);
11736 /* X % 0, return X % 0 unchanged so that we can get the
11737 proper warnings and errors. */
11738 if (integer_zerop (arg1))
11741 /* 0 % X is always zero, but be sure to preserve any side
11742 effects in X. Place this after checking for X == 0. */
11743 if (integer_zerop (arg0))
11744 return omit_one_operand (type, integer_zero_node, arg1);
11746 /* X % -1 is zero. */
11747 if (!TYPE_UNSIGNED (type)
11748 && TREE_CODE (arg1) == INTEGER_CST
11749 && TREE_INT_CST_LOW (arg1) == (unsigned HOST_WIDE_INT) -1
11750 && TREE_INT_CST_HIGH (arg1) == -1)
11751 return omit_one_operand (type, integer_zero_node, arg0);
11753 /* Optimize TRUNC_MOD_EXPR by a power of two into a BIT_AND_EXPR,
11754 i.e. "X % C" into "X & (C - 1)", if X and C are positive. */
11755 strict_overflow_p = false;
11756 if ((code == TRUNC_MOD_EXPR || code == FLOOR_MOD_EXPR)
11757 && (TYPE_UNSIGNED (type)
11758 || tree_expr_nonnegative_warnv_p (op0, &strict_overflow_p)))
11761 /* Also optimize A % (C << N) where C is a power of 2,
11762 to A & ((C << N) - 1). */
11763 if (TREE_CODE (arg1) == LSHIFT_EXPR)
11764 c = TREE_OPERAND (arg1, 0);
11766 if (integer_pow2p (c) && tree_int_cst_sgn (c) > 0)
11768 tree mask = fold_build2 (MINUS_EXPR, TREE_TYPE (arg1), arg1,
11769 build_int_cst (TREE_TYPE (arg1), 1));
11770 if (strict_overflow_p)
11771 fold_overflow_warning (("assuming signed overflow does not "
11772 "occur when simplifying "
11773 "X % (power of two)"),
11774 WARN_STRICT_OVERFLOW_MISC);
11775 return fold_build2 (BIT_AND_EXPR, type,
11776 fold_convert (type, arg0),
11777 fold_convert (type, mask));
11781 /* X % -C is the same as X % C. */
11782 if (code == TRUNC_MOD_EXPR
11783 && !TYPE_UNSIGNED (type)
11784 && TREE_CODE (arg1) == INTEGER_CST
11785 && !TREE_OVERFLOW (arg1)
11786 && TREE_INT_CST_HIGH (arg1) < 0
11787 && !TYPE_OVERFLOW_TRAPS (type)
11788 /* Avoid this transformation if C is INT_MIN, i.e. C == -C. */
11789 && !sign_bit_p (arg1, arg1))
11790 return fold_build2 (code, type, fold_convert (type, arg0),
11791 fold_convert (type, negate_expr (arg1)));
11793 /* X % -Y is the same as X % Y. */
11794 if (code == TRUNC_MOD_EXPR
11795 && !TYPE_UNSIGNED (type)
11796 && TREE_CODE (arg1) == NEGATE_EXPR
11797 && !TYPE_OVERFLOW_TRAPS (type))
11798 return fold_build2 (code, type, fold_convert (type, arg0),
11799 fold_convert (type, TREE_OPERAND (arg1, 0)));
11801 if (TREE_CODE (arg1) == INTEGER_CST
11802 && 0 != (tem = extract_muldiv (op0, arg1, code, NULL_TREE,
11803 &strict_overflow_p)))
11805 if (strict_overflow_p)
11806 fold_overflow_warning (("assuming signed overflow does not occur "
11807 "when simplifying modulus"),
11808 WARN_STRICT_OVERFLOW_MISC);
11809 return fold_convert (type, tem);
11816 if (integer_all_onesp (arg0))
11817 return omit_one_operand (type, arg0, arg1);
11821 /* Optimize -1 >> x for arithmetic right shifts. */
11822 if (integer_all_onesp (arg0) && !TYPE_UNSIGNED (type)
11823 && tree_expr_nonnegative_p (arg1))
11824 return omit_one_operand (type, arg0, arg1);
11825 /* ... fall through ... */
11829 if (integer_zerop (arg1))
11830 return non_lvalue (fold_convert (type, arg0));
11831 if (integer_zerop (arg0))
11832 return omit_one_operand (type, arg0, arg1);
11834 /* Since negative shift count is not well-defined,
11835 don't try to compute it in the compiler. */
11836 if (TREE_CODE (arg1) == INTEGER_CST && tree_int_cst_sgn (arg1) < 0)
11839 /* Turn (a OP c1) OP c2 into a OP (c1+c2). */
11840 if (TREE_CODE (op0) == code && host_integerp (arg1, false)
11841 && TREE_INT_CST_LOW (arg1) < TYPE_PRECISION (type)
11842 && host_integerp (TREE_OPERAND (arg0, 1), false)
11843 && TREE_INT_CST_LOW (TREE_OPERAND (arg0, 1)) < TYPE_PRECISION (type))
11845 HOST_WIDE_INT low = (TREE_INT_CST_LOW (TREE_OPERAND (arg0, 1))
11846 + TREE_INT_CST_LOW (arg1));
11848 /* Deal with a OP (c1 + c2) being undefined but (a OP c1) OP c2
11849 being well defined. */
11850 if (low >= TYPE_PRECISION (type))
11852 if (code == LROTATE_EXPR || code == RROTATE_EXPR)
11853 low = low % TYPE_PRECISION (type);
11854 else if (TYPE_UNSIGNED (type) || code == LSHIFT_EXPR)
11855 return build_int_cst (type, 0);
11857 low = TYPE_PRECISION (type) - 1;
11860 return fold_build2 (code, type, TREE_OPERAND (arg0, 0),
11861 build_int_cst (type, low));
11864 /* Transform (x >> c) << c into x & (-1<<c), or transform (x << c) >> c
11865 into x & ((unsigned)-1 >> c) for unsigned types. */
11866 if (((code == LSHIFT_EXPR && TREE_CODE (arg0) == RSHIFT_EXPR)
11867 || (TYPE_UNSIGNED (type)
11868 && code == RSHIFT_EXPR && TREE_CODE (arg0) == LSHIFT_EXPR))
11869 && host_integerp (arg1, false)
11870 && TREE_INT_CST_LOW (arg1) < TYPE_PRECISION (type)
11871 && host_integerp (TREE_OPERAND (arg0, 1), false)
11872 && TREE_INT_CST_LOW (TREE_OPERAND (arg0, 1)) < TYPE_PRECISION (type))
11874 HOST_WIDE_INT low0 = TREE_INT_CST_LOW (TREE_OPERAND (arg0, 1));
11875 HOST_WIDE_INT low1 = TREE_INT_CST_LOW (arg1);
11881 arg00 = fold_convert (type, TREE_OPERAND (arg0, 0));
11883 lshift = build_int_cst (type, -1);
11884 lshift = int_const_binop (code, lshift, arg1, 0);
11886 return fold_build2 (BIT_AND_EXPR, type, arg00, lshift);
11890 /* Rewrite an LROTATE_EXPR by a constant into an
11891 RROTATE_EXPR by a new constant. */
11892 if (code == LROTATE_EXPR && TREE_CODE (arg1) == INTEGER_CST)
11894 tree tem = build_int_cst (TREE_TYPE (arg1),
11895 TYPE_PRECISION (type));
11896 tem = const_binop (MINUS_EXPR, tem, arg1, 0);
11897 return fold_build2 (RROTATE_EXPR, type, op0, tem);
11900 /* If we have a rotate of a bit operation with the rotate count and
11901 the second operand of the bit operation both constant,
11902 permute the two operations. */
11903 if (code == RROTATE_EXPR && TREE_CODE (arg1) == INTEGER_CST
11904 && (TREE_CODE (arg0) == BIT_AND_EXPR
11905 || TREE_CODE (arg0) == BIT_IOR_EXPR
11906 || TREE_CODE (arg0) == BIT_XOR_EXPR)
11907 && TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST)
11908 return fold_build2 (TREE_CODE (arg0), type,
11909 fold_build2 (code, type,
11910 TREE_OPERAND (arg0, 0), arg1),
11911 fold_build2 (code, type,
11912 TREE_OPERAND (arg0, 1), arg1));
11914 /* Two consecutive rotates adding up to the precision of the
11915 type can be ignored. */
11916 if (code == RROTATE_EXPR && TREE_CODE (arg1) == INTEGER_CST
11917 && TREE_CODE (arg0) == RROTATE_EXPR
11918 && TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST
11919 && TREE_INT_CST_HIGH (arg1) == 0
11920 && TREE_INT_CST_HIGH (TREE_OPERAND (arg0, 1)) == 0
11921 && ((TREE_INT_CST_LOW (arg1)
11922 + TREE_INT_CST_LOW (TREE_OPERAND (arg0, 1)))
11923 == (unsigned int) TYPE_PRECISION (type)))
11924 return TREE_OPERAND (arg0, 0);
11926 /* Fold (X & C2) << C1 into (X << C1) & (C2 << C1)
11927 (X & C2) >> C1 into (X >> C1) & (C2 >> C1)
11928 if the latter can be further optimized. */
11929 if ((code == LSHIFT_EXPR || code == RSHIFT_EXPR)
11930 && TREE_CODE (arg0) == BIT_AND_EXPR
11931 && TREE_CODE (arg1) == INTEGER_CST
11932 && TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST)
11934 tree mask = fold_build2 (code, type,
11935 fold_convert (type, TREE_OPERAND (arg0, 1)),
11937 tree shift = fold_build2 (code, type,
11938 fold_convert (type, TREE_OPERAND (arg0, 0)),
11940 tem = fold_binary (BIT_AND_EXPR, type, shift, mask);
11948 if (operand_equal_p (arg0, arg1, 0))
11949 return omit_one_operand (type, arg0, arg1);
11950 if (INTEGRAL_TYPE_P (type)
11951 && operand_equal_p (arg1, TYPE_MIN_VALUE (type), OEP_ONLY_CONST))
11952 return omit_one_operand (type, arg1, arg0);
11953 tem = fold_minmax (MIN_EXPR, type, arg0, arg1);
11959 if (operand_equal_p (arg0, arg1, 0))
11960 return omit_one_operand (type, arg0, arg1);
11961 if (INTEGRAL_TYPE_P (type)
11962 && TYPE_MAX_VALUE (type)
11963 && operand_equal_p (arg1, TYPE_MAX_VALUE (type), OEP_ONLY_CONST))
11964 return omit_one_operand (type, arg1, arg0);
11965 tem = fold_minmax (MAX_EXPR, type, arg0, arg1);
11970 case TRUTH_ANDIF_EXPR:
11971 /* Note that the operands of this must be ints
11972 and their values must be 0 or 1.
11973 ("true" is a fixed value perhaps depending on the language.) */
11974 /* If first arg is constant zero, return it. */
11975 if (integer_zerop (arg0))
11976 return fold_convert (type, arg0);
11977 case TRUTH_AND_EXPR:
11978 /* If either arg is constant true, drop it. */
11979 if (TREE_CODE (arg0) == INTEGER_CST && ! integer_zerop (arg0))
11980 return non_lvalue (fold_convert (type, arg1));
11981 if (TREE_CODE (arg1) == INTEGER_CST && ! integer_zerop (arg1)
11982 /* Preserve sequence points. */
11983 && (code != TRUTH_ANDIF_EXPR || ! TREE_SIDE_EFFECTS (arg0)))
11984 return non_lvalue (fold_convert (type, arg0));
11985 /* If second arg is constant zero, result is zero, but first arg
11986 must be evaluated. */
11987 if (integer_zerop (arg1))
11988 return omit_one_operand (type, arg1, arg0);
11989 /* Likewise for first arg, but note that only the TRUTH_AND_EXPR
11990 case will be handled here. */
11991 if (integer_zerop (arg0))
11992 return omit_one_operand (type, arg0, arg1);
11994 /* !X && X is always false. */
11995 if (TREE_CODE (arg0) == TRUTH_NOT_EXPR
11996 && operand_equal_p (TREE_OPERAND (arg0, 0), arg1, 0))
11997 return omit_one_operand (type, integer_zero_node, arg1);
11998 /* X && !X is always false. */
11999 if (TREE_CODE (arg1) == TRUTH_NOT_EXPR
12000 && operand_equal_p (arg0, TREE_OPERAND (arg1, 0), 0))
12001 return omit_one_operand (type, integer_zero_node, arg0);
12003 /* A < X && A + 1 > Y ==> A < X && A >= Y. Normally A + 1 > Y
12004 means A >= Y && A != MAX, but in this case we know that
12007 if (!TREE_SIDE_EFFECTS (arg0)
12008 && !TREE_SIDE_EFFECTS (arg1))
12010 tem = fold_to_nonsharp_ineq_using_bound (arg0, arg1);
12011 if (tem && !operand_equal_p (tem, arg0, 0))
12012 return fold_build2 (code, type, tem, arg1);
12014 tem = fold_to_nonsharp_ineq_using_bound (arg1, arg0);
12015 if (tem && !operand_equal_p (tem, arg1, 0))
12016 return fold_build2 (code, type, arg0, tem);
12020 /* We only do these simplifications if we are optimizing. */
12024 /* Check for things like (A || B) && (A || C). We can convert this
12025 to A || (B && C). Note that either operator can be any of the four
12026 truth and/or operations and the transformation will still be
12027 valid. Also note that we only care about order for the
12028 ANDIF and ORIF operators. If B contains side effects, this
12029 might change the truth-value of A. */
12030 if (TREE_CODE (arg0) == TREE_CODE (arg1)
12031 && (TREE_CODE (arg0) == TRUTH_ANDIF_EXPR
12032 || TREE_CODE (arg0) == TRUTH_ORIF_EXPR
12033 || TREE_CODE (arg0) == TRUTH_AND_EXPR
12034 || TREE_CODE (arg0) == TRUTH_OR_EXPR)
12035 && ! TREE_SIDE_EFFECTS (TREE_OPERAND (arg0, 1)))
12037 tree a00 = TREE_OPERAND (arg0, 0);
12038 tree a01 = TREE_OPERAND (arg0, 1);
12039 tree a10 = TREE_OPERAND (arg1, 0);
12040 tree a11 = TREE_OPERAND (arg1, 1);
12041 int commutative = ((TREE_CODE (arg0) == TRUTH_OR_EXPR
12042 || TREE_CODE (arg0) == TRUTH_AND_EXPR)
12043 && (code == TRUTH_AND_EXPR
12044 || code == TRUTH_OR_EXPR));
12046 if (operand_equal_p (a00, a10, 0))
12047 return fold_build2 (TREE_CODE (arg0), type, a00,
12048 fold_build2 (code, type, a01, a11));
12049 else if (commutative && operand_equal_p (a00, a11, 0))
12050 return fold_build2 (TREE_CODE (arg0), type, a00,
12051 fold_build2 (code, type, a01, a10));
12052 else if (commutative && operand_equal_p (a01, a10, 0))
12053 return fold_build2 (TREE_CODE (arg0), type, a01,
12054 fold_build2 (code, type, a00, a11));
12056 /* This case if tricky because we must either have commutative
12057 operators or else A10 must not have side-effects. */
12059 else if ((commutative || ! TREE_SIDE_EFFECTS (a10))
12060 && operand_equal_p (a01, a11, 0))
12061 return fold_build2 (TREE_CODE (arg0), type,
12062 fold_build2 (code, type, a00, a10),
12066 /* See if we can build a range comparison. */
12067 if (0 != (tem = fold_range_test (code, type, op0, op1)))
12070 /* Check for the possibility of merging component references. If our
12071 lhs is another similar operation, try to merge its rhs with our
12072 rhs. Then try to merge our lhs and rhs. */
12073 if (TREE_CODE (arg0) == code
12074 && 0 != (tem = fold_truthop (code, type,
12075 TREE_OPERAND (arg0, 1), arg1)))
12076 return fold_build2 (code, type, TREE_OPERAND (arg0, 0), tem);
12078 if ((tem = fold_truthop (code, type, arg0, arg1)) != 0)
12083 case TRUTH_ORIF_EXPR:
12084 /* Note that the operands of this must be ints
12085 and their values must be 0 or true.
12086 ("true" is a fixed value perhaps depending on the language.) */
12087 /* If first arg is constant true, return it. */
12088 if (TREE_CODE (arg0) == INTEGER_CST && ! integer_zerop (arg0))
12089 return fold_convert (type, arg0);
12090 case TRUTH_OR_EXPR:
12091 /* If either arg is constant zero, drop it. */
12092 if (TREE_CODE (arg0) == INTEGER_CST && integer_zerop (arg0))
12093 return non_lvalue (fold_convert (type, arg1));
12094 if (TREE_CODE (arg1) == INTEGER_CST && integer_zerop (arg1)
12095 /* Preserve sequence points. */
12096 && (code != TRUTH_ORIF_EXPR || ! TREE_SIDE_EFFECTS (arg0)))
12097 return non_lvalue (fold_convert (type, arg0));
12098 /* If second arg is constant true, result is true, but we must
12099 evaluate first arg. */
12100 if (TREE_CODE (arg1) == INTEGER_CST && ! integer_zerop (arg1))
12101 return omit_one_operand (type, arg1, arg0);
12102 /* Likewise for first arg, but note this only occurs here for
12104 if (TREE_CODE (arg0) == INTEGER_CST && ! integer_zerop (arg0))
12105 return omit_one_operand (type, arg0, arg1);
12107 /* !X || X is always true. */
12108 if (TREE_CODE (arg0) == TRUTH_NOT_EXPR
12109 && operand_equal_p (TREE_OPERAND (arg0, 0), arg1, 0))
12110 return omit_one_operand (type, integer_one_node, arg1);
12111 /* X || !X is always true. */
12112 if (TREE_CODE (arg1) == TRUTH_NOT_EXPR
12113 && operand_equal_p (arg0, TREE_OPERAND (arg1, 0), 0))
12114 return omit_one_operand (type, integer_one_node, arg0);
12118 case TRUTH_XOR_EXPR:
12119 /* If the second arg is constant zero, drop it. */
12120 if (integer_zerop (arg1))
12121 return non_lvalue (fold_convert (type, arg0));
12122 /* If the second arg is constant true, this is a logical inversion. */
12123 if (integer_onep (arg1))
12125 /* Only call invert_truthvalue if operand is a truth value. */
12126 if (TREE_CODE (TREE_TYPE (arg0)) != BOOLEAN_TYPE)
12127 tem = fold_build1 (TRUTH_NOT_EXPR, TREE_TYPE (arg0), arg0);
12129 tem = invert_truthvalue (arg0);
12130 return non_lvalue (fold_convert (type, tem));
12132 /* Identical arguments cancel to zero. */
12133 if (operand_equal_p (arg0, arg1, 0))
12134 return omit_one_operand (type, integer_zero_node, arg0);
12136 /* !X ^ X is always true. */
12137 if (TREE_CODE (arg0) == TRUTH_NOT_EXPR
12138 && operand_equal_p (TREE_OPERAND (arg0, 0), arg1, 0))
12139 return omit_one_operand (type, integer_one_node, arg1);
12141 /* X ^ !X is always true. */
12142 if (TREE_CODE (arg1) == TRUTH_NOT_EXPR
12143 && operand_equal_p (arg0, TREE_OPERAND (arg1, 0), 0))
12144 return omit_one_operand (type, integer_one_node, arg0);
12150 tem = fold_comparison (code, type, op0, op1);
12151 if (tem != NULL_TREE)
12154 /* bool_var != 0 becomes bool_var. */
12155 if (TREE_CODE (TREE_TYPE (arg0)) == BOOLEAN_TYPE && integer_zerop (arg1)
12156 && code == NE_EXPR)
12157 return non_lvalue (fold_convert (type, arg0));
12159 /* bool_var == 1 becomes bool_var. */
12160 if (TREE_CODE (TREE_TYPE (arg0)) == BOOLEAN_TYPE && integer_onep (arg1)
12161 && code == EQ_EXPR)
12162 return non_lvalue (fold_convert (type, arg0));
12164 /* bool_var != 1 becomes !bool_var. */
12165 if (TREE_CODE (TREE_TYPE (arg0)) == BOOLEAN_TYPE && integer_onep (arg1)
12166 && code == NE_EXPR)
12167 return fold_build1 (TRUTH_NOT_EXPR, type, fold_convert (type, arg0));
12169 /* bool_var == 0 becomes !bool_var. */
12170 if (TREE_CODE (TREE_TYPE (arg0)) == BOOLEAN_TYPE && integer_zerop (arg1)
12171 && code == EQ_EXPR)
12172 return fold_build1 (TRUTH_NOT_EXPR, type, fold_convert (type, arg0));
12174 /* If this is an equality comparison of the address of two non-weak,
12175 unaliased symbols neither of which are extern (since we do not
12176 have access to attributes for externs), then we know the result. */
12177 if (TREE_CODE (arg0) == ADDR_EXPR
12178 && VAR_OR_FUNCTION_DECL_P (TREE_OPERAND (arg0, 0))
12179 && ! DECL_WEAK (TREE_OPERAND (arg0, 0))
12180 && ! lookup_attribute ("alias",
12181 DECL_ATTRIBUTES (TREE_OPERAND (arg0, 0)))
12182 && ! DECL_EXTERNAL (TREE_OPERAND (arg0, 0))
12183 && TREE_CODE (arg1) == ADDR_EXPR
12184 && VAR_OR_FUNCTION_DECL_P (TREE_OPERAND (arg1, 0))
12185 && ! DECL_WEAK (TREE_OPERAND (arg1, 0))
12186 && ! lookup_attribute ("alias",
12187 DECL_ATTRIBUTES (TREE_OPERAND (arg1, 0)))
12188 && ! DECL_EXTERNAL (TREE_OPERAND (arg1, 0)))
12190 /* We know that we're looking at the address of two
12191 non-weak, unaliased, static _DECL nodes.
12193 It is both wasteful and incorrect to call operand_equal_p
12194 to compare the two ADDR_EXPR nodes. It is wasteful in that
12195 all we need to do is test pointer equality for the arguments
12196 to the two ADDR_EXPR nodes. It is incorrect to use
12197 operand_equal_p as that function is NOT equivalent to a
12198 C equality test. It can in fact return false for two
12199 objects which would test as equal using the C equality
12201 bool equal = TREE_OPERAND (arg0, 0) == TREE_OPERAND (arg1, 0);
12202 return constant_boolean_node (equal
12203 ? code == EQ_EXPR : code != EQ_EXPR,
12207 /* If this is an EQ or NE comparison of a constant with a PLUS_EXPR or
12208 a MINUS_EXPR of a constant, we can convert it into a comparison with
12209 a revised constant as long as no overflow occurs. */
12210 if (TREE_CODE (arg1) == INTEGER_CST
12211 && (TREE_CODE (arg0) == PLUS_EXPR
12212 || TREE_CODE (arg0) == MINUS_EXPR)
12213 && TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST
12214 && 0 != (tem = const_binop (TREE_CODE (arg0) == PLUS_EXPR
12215 ? MINUS_EXPR : PLUS_EXPR,
12216 fold_convert (TREE_TYPE (arg0), arg1),
12217 TREE_OPERAND (arg0, 1), 0))
12218 && !TREE_OVERFLOW (tem))
12219 return fold_build2 (code, type, TREE_OPERAND (arg0, 0), tem);
12221 /* Similarly for a NEGATE_EXPR. */
12222 if (TREE_CODE (arg0) == NEGATE_EXPR
12223 && TREE_CODE (arg1) == INTEGER_CST
12224 && 0 != (tem = negate_expr (arg1))
12225 && TREE_CODE (tem) == INTEGER_CST
12226 && !TREE_OVERFLOW (tem))
12227 return fold_build2 (code, type, TREE_OPERAND (arg0, 0), tem);
12229 /* Similarly for a BIT_XOR_EXPR; X ^ C1 == C2 is X == (C1 ^ C2). */
12230 if (TREE_CODE (arg0) == BIT_XOR_EXPR
12231 && TREE_CODE (arg1) == INTEGER_CST
12232 && TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST)
12233 return fold_build2 (code, type, TREE_OPERAND (arg0, 0),
12234 fold_build2 (BIT_XOR_EXPR, TREE_TYPE (arg0),
12235 fold_convert (TREE_TYPE (arg0), arg1),
12236 TREE_OPERAND (arg0, 1)));
12238 /* Transform comparisons of the form X +- C CMP X. */
12239 if ((TREE_CODE (arg0) == PLUS_EXPR || TREE_CODE (arg0) == MINUS_EXPR)
12240 && operand_equal_p (TREE_OPERAND (arg0, 0), arg1, 0)
12241 && TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST
12242 && (INTEGRAL_TYPE_P (TREE_TYPE (arg0))
12243 || POINTER_TYPE_P (TREE_TYPE (arg0))))
12245 tree cst = TREE_OPERAND (arg0, 1);
12247 if (code == EQ_EXPR
12248 && !integer_zerop (cst))
12249 return omit_two_operands (type, boolean_false_node,
12250 TREE_OPERAND (arg0, 0), arg1);
12252 return omit_two_operands (type, boolean_true_node,
12253 TREE_OPERAND (arg0, 0), arg1);
12256 /* If we have X - Y == 0, we can convert that to X == Y and similarly
12257 for !=. Don't do this for ordered comparisons due to overflow. */
12258 if (TREE_CODE (arg0) == MINUS_EXPR
12259 && integer_zerop (arg1))
12260 return fold_build2 (code, type,
12261 TREE_OPERAND (arg0, 0), TREE_OPERAND (arg0, 1));
12263 /* Convert ABS_EXPR<x> == 0 or ABS_EXPR<x> != 0 to x == 0 or x != 0. */
12264 if (TREE_CODE (arg0) == ABS_EXPR
12265 && (integer_zerop (arg1) || real_zerop (arg1)))
12266 return fold_build2 (code, type, TREE_OPERAND (arg0, 0), arg1);
12268 /* If this is an EQ or NE comparison with zero and ARG0 is
12269 (1 << foo) & bar, convert it to (bar >> foo) & 1. Both require
12270 two operations, but the latter can be done in one less insn
12271 on machines that have only two-operand insns or on which a
12272 constant cannot be the first operand. */
12273 if (TREE_CODE (arg0) == BIT_AND_EXPR
12274 && integer_zerop (arg1))
12276 tree arg00 = TREE_OPERAND (arg0, 0);
12277 tree arg01 = TREE_OPERAND (arg0, 1);
12278 if (TREE_CODE (arg00) == LSHIFT_EXPR
12279 && integer_onep (TREE_OPERAND (arg00, 0)))
12281 tree tem = fold_build2 (RSHIFT_EXPR, TREE_TYPE (arg00),
12282 arg01, TREE_OPERAND (arg00, 1));
12283 tem = fold_build2 (BIT_AND_EXPR, TREE_TYPE (arg0), tem,
12284 build_int_cst (TREE_TYPE (arg0), 1));
12285 return fold_build2 (code, type,
12286 fold_convert (TREE_TYPE (arg1), tem), arg1);
12288 else if (TREE_CODE (arg01) == LSHIFT_EXPR
12289 && integer_onep (TREE_OPERAND (arg01, 0)))
12291 tree tem = fold_build2 (RSHIFT_EXPR, TREE_TYPE (arg01),
12292 arg00, TREE_OPERAND (arg01, 1));
12293 tem = fold_build2 (BIT_AND_EXPR, TREE_TYPE (arg0), tem,
12294 build_int_cst (TREE_TYPE (arg0), 1));
12295 return fold_build2 (code, type,
12296 fold_convert (TREE_TYPE (arg1), tem), arg1);
12300 /* If this is an NE or EQ comparison of zero against the result of a
12301 signed MOD operation whose second operand is a power of 2, make
12302 the MOD operation unsigned since it is simpler and equivalent. */
12303 if (integer_zerop (arg1)
12304 && !TYPE_UNSIGNED (TREE_TYPE (arg0))
12305 && (TREE_CODE (arg0) == TRUNC_MOD_EXPR
12306 || TREE_CODE (arg0) == CEIL_MOD_EXPR
12307 || TREE_CODE (arg0) == FLOOR_MOD_EXPR
12308 || TREE_CODE (arg0) == ROUND_MOD_EXPR)
12309 && integer_pow2p (TREE_OPERAND (arg0, 1)))
12311 tree newtype = unsigned_type_for (TREE_TYPE (arg0));
12312 tree newmod = fold_build2 (TREE_CODE (arg0), newtype,
12313 fold_convert (newtype,
12314 TREE_OPERAND (arg0, 0)),
12315 fold_convert (newtype,
12316 TREE_OPERAND (arg0, 1)));
12318 return fold_build2 (code, type, newmod,
12319 fold_convert (newtype, arg1));
12322 /* Fold ((X >> C1) & C2) == 0 and ((X >> C1) & C2) != 0 where
12323 C1 is a valid shift constant, and C2 is a power of two, i.e.
12325 if (TREE_CODE (arg0) == BIT_AND_EXPR
12326 && TREE_CODE (TREE_OPERAND (arg0, 0)) == RSHIFT_EXPR
12327 && TREE_CODE (TREE_OPERAND (TREE_OPERAND (arg0, 0), 1))
12329 && integer_pow2p (TREE_OPERAND (arg0, 1))
12330 && integer_zerop (arg1))
12332 tree itype = TREE_TYPE (arg0);
12333 unsigned HOST_WIDE_INT prec = TYPE_PRECISION (itype);
12334 tree arg001 = TREE_OPERAND (TREE_OPERAND (arg0, 0), 1);
12336 /* Check for a valid shift count. */
12337 if (TREE_INT_CST_HIGH (arg001) == 0
12338 && TREE_INT_CST_LOW (arg001) < prec)
12340 tree arg01 = TREE_OPERAND (arg0, 1);
12341 tree arg000 = TREE_OPERAND (TREE_OPERAND (arg0, 0), 0);
12342 unsigned HOST_WIDE_INT log2 = tree_log2 (arg01);
12343 /* If (C2 << C1) doesn't overflow, then ((X >> C1) & C2) != 0
12344 can be rewritten as (X & (C2 << C1)) != 0. */
12345 if ((log2 + TREE_INT_CST_LOW (arg001)) < prec)
12347 tem = fold_build2 (LSHIFT_EXPR, itype, arg01, arg001);
12348 tem = fold_build2 (BIT_AND_EXPR, itype, arg000, tem);
12349 return fold_build2 (code, type, tem, arg1);
12351 /* Otherwise, for signed (arithmetic) shifts,
12352 ((X >> C1) & C2) != 0 is rewritten as X < 0, and
12353 ((X >> C1) & C2) == 0 is rewritten as X >= 0. */
12354 else if (!TYPE_UNSIGNED (itype))
12355 return fold_build2 (code == EQ_EXPR ? GE_EXPR : LT_EXPR, type,
12356 arg000, build_int_cst (itype, 0));
12357 /* Otherwise, of unsigned (logical) shifts,
12358 ((X >> C1) & C2) != 0 is rewritten as (X,false), and
12359 ((X >> C1) & C2) == 0 is rewritten as (X,true). */
12361 return omit_one_operand (type,
12362 code == EQ_EXPR ? integer_one_node
12363 : integer_zero_node,
12368 /* If this is an NE comparison of zero with an AND of one, remove the
12369 comparison since the AND will give the correct value. */
12370 if (code == NE_EXPR
12371 && integer_zerop (arg1)
12372 && TREE_CODE (arg0) == BIT_AND_EXPR
12373 && integer_onep (TREE_OPERAND (arg0, 1)))
12374 return fold_convert (type, arg0);
12376 /* If we have (A & C) == C where C is a power of 2, convert this into
12377 (A & C) != 0. Similarly for NE_EXPR. */
12378 if (TREE_CODE (arg0) == BIT_AND_EXPR
12379 && integer_pow2p (TREE_OPERAND (arg0, 1))
12380 && operand_equal_p (TREE_OPERAND (arg0, 1), arg1, 0))
12381 return fold_build2 (code == EQ_EXPR ? NE_EXPR : EQ_EXPR, type,
12382 arg0, fold_convert (TREE_TYPE (arg0),
12383 integer_zero_node));
12385 /* If we have (A & C) != 0 or (A & C) == 0 and C is the sign
12386 bit, then fold the expression into A < 0 or A >= 0. */
12387 tem = fold_single_bit_test_into_sign_test (code, arg0, arg1, type);
12391 /* If we have (A & C) == D where D & ~C != 0, convert this into 0.
12392 Similarly for NE_EXPR. */
12393 if (TREE_CODE (arg0) == BIT_AND_EXPR
12394 && TREE_CODE (arg1) == INTEGER_CST
12395 && TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST)
12397 tree notc = fold_build1 (BIT_NOT_EXPR,
12398 TREE_TYPE (TREE_OPERAND (arg0, 1)),
12399 TREE_OPERAND (arg0, 1));
12400 tree dandnotc = fold_build2 (BIT_AND_EXPR, TREE_TYPE (arg0),
12402 tree rslt = code == EQ_EXPR ? integer_zero_node : integer_one_node;
12403 if (integer_nonzerop (dandnotc))
12404 return omit_one_operand (type, rslt, arg0);
12407 /* If we have (A | C) == D where C & ~D != 0, convert this into 0.
12408 Similarly for NE_EXPR. */
12409 if (TREE_CODE (arg0) == BIT_IOR_EXPR
12410 && TREE_CODE (arg1) == INTEGER_CST
12411 && TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST)
12413 tree notd = fold_build1 (BIT_NOT_EXPR, TREE_TYPE (arg1), arg1);
12414 tree candnotd = fold_build2 (BIT_AND_EXPR, TREE_TYPE (arg0),
12415 TREE_OPERAND (arg0, 1), notd);
12416 tree rslt = code == EQ_EXPR ? integer_zero_node : integer_one_node;
12417 if (integer_nonzerop (candnotd))
12418 return omit_one_operand (type, rslt, arg0);
12421 /* If this is a comparison of a field, we may be able to simplify it. */
12422 if ((TREE_CODE (arg0) == COMPONENT_REF
12423 || TREE_CODE (arg0) == BIT_FIELD_REF)
12424 /* Handle the constant case even without -O
12425 to make sure the warnings are given. */
12426 && (optimize || TREE_CODE (arg1) == INTEGER_CST))
12428 t1 = optimize_bit_field_compare (code, type, arg0, arg1);
12433 /* Optimize comparisons of strlen vs zero to a compare of the
12434 first character of the string vs zero. To wit,
12435 strlen(ptr) == 0 => *ptr == 0
12436 strlen(ptr) != 0 => *ptr != 0
12437 Other cases should reduce to one of these two (or a constant)
12438 due to the return value of strlen being unsigned. */
12439 if (TREE_CODE (arg0) == CALL_EXPR
12440 && integer_zerop (arg1))
12442 tree fndecl = get_callee_fndecl (arg0);
12445 && DECL_BUILT_IN_CLASS (fndecl) == BUILT_IN_NORMAL
12446 && DECL_FUNCTION_CODE (fndecl) == BUILT_IN_STRLEN
12447 && call_expr_nargs (arg0) == 1
12448 && TREE_CODE (TREE_TYPE (CALL_EXPR_ARG (arg0, 0))) == POINTER_TYPE)
12450 tree iref = build_fold_indirect_ref (CALL_EXPR_ARG (arg0, 0));
12451 return fold_build2 (code, type, iref,
12452 build_int_cst (TREE_TYPE (iref), 0));
12456 /* Fold (X >> C) != 0 into X < 0 if C is one less than the width
12457 of X. Similarly fold (X >> C) == 0 into X >= 0. */
12458 if (TREE_CODE (arg0) == RSHIFT_EXPR
12459 && integer_zerop (arg1)
12460 && TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST)
12462 tree arg00 = TREE_OPERAND (arg0, 0);
12463 tree arg01 = TREE_OPERAND (arg0, 1);
12464 tree itype = TREE_TYPE (arg00);
12465 if (TREE_INT_CST_HIGH (arg01) == 0
12466 && TREE_INT_CST_LOW (arg01)
12467 == (unsigned HOST_WIDE_INT) (TYPE_PRECISION (itype) - 1))
12469 if (TYPE_UNSIGNED (itype))
12471 itype = signed_type_for (itype);
12472 arg00 = fold_convert (itype, arg00);
12474 return fold_build2 (code == EQ_EXPR ? GE_EXPR : LT_EXPR,
12475 type, arg00, build_int_cst (itype, 0));
12479 /* (X ^ Y) == 0 becomes X == Y, and (X ^ Y) != 0 becomes X != Y. */
12480 if (integer_zerop (arg1)
12481 && TREE_CODE (arg0) == BIT_XOR_EXPR)
12482 return fold_build2 (code, type, TREE_OPERAND (arg0, 0),
12483 TREE_OPERAND (arg0, 1));
12485 /* (X ^ Y) == Y becomes X == 0. We know that Y has no side-effects. */
12486 if (TREE_CODE (arg0) == BIT_XOR_EXPR
12487 && operand_equal_p (TREE_OPERAND (arg0, 1), arg1, 0))
12488 return fold_build2 (code, type, TREE_OPERAND (arg0, 0),
12489 build_int_cst (TREE_TYPE (arg1), 0));
12490 /* Likewise (X ^ Y) == X becomes Y == 0. X has no side-effects. */
12491 if (TREE_CODE (arg0) == BIT_XOR_EXPR
12492 && operand_equal_p (TREE_OPERAND (arg0, 0), arg1, 0)
12493 && reorder_operands_p (TREE_OPERAND (arg0, 1), arg1))
12494 return fold_build2 (code, type, TREE_OPERAND (arg0, 1),
12495 build_int_cst (TREE_TYPE (arg1), 0));
12497 /* (X ^ C1) op C2 can be rewritten as X op (C1 ^ C2). */
12498 if (TREE_CODE (arg0) == BIT_XOR_EXPR
12499 && TREE_CODE (arg1) == INTEGER_CST
12500 && TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST)
12501 return fold_build2 (code, type, TREE_OPERAND (arg0, 0),
12502 fold_build2 (BIT_XOR_EXPR, TREE_TYPE (arg1),
12503 TREE_OPERAND (arg0, 1), arg1));
12505 /* Fold (~X & C) == 0 into (X & C) != 0 and (~X & C) != 0 into
12506 (X & C) == 0 when C is a single bit. */
12507 if (TREE_CODE (arg0) == BIT_AND_EXPR
12508 && TREE_CODE (TREE_OPERAND (arg0, 0)) == BIT_NOT_EXPR
12509 && integer_zerop (arg1)
12510 && integer_pow2p (TREE_OPERAND (arg0, 1)))
12512 tem = fold_build2 (BIT_AND_EXPR, TREE_TYPE (arg0),
12513 TREE_OPERAND (TREE_OPERAND (arg0, 0), 0),
12514 TREE_OPERAND (arg0, 1));
12515 return fold_build2 (code == EQ_EXPR ? NE_EXPR : EQ_EXPR,
12519 /* Fold ((X & C) ^ C) eq/ne 0 into (X & C) ne/eq 0, when the
12520 constant C is a power of two, i.e. a single bit. */
12521 if (TREE_CODE (arg0) == BIT_XOR_EXPR
12522 && TREE_CODE (TREE_OPERAND (arg0, 0)) == BIT_AND_EXPR
12523 && integer_zerop (arg1)
12524 && integer_pow2p (TREE_OPERAND (arg0, 1))
12525 && operand_equal_p (TREE_OPERAND (TREE_OPERAND (arg0, 0), 1),
12526 TREE_OPERAND (arg0, 1), OEP_ONLY_CONST))
12528 tree arg00 = TREE_OPERAND (arg0, 0);
12529 return fold_build2 (code == EQ_EXPR ? NE_EXPR : EQ_EXPR, type,
12530 arg00, build_int_cst (TREE_TYPE (arg00), 0));
12533 /* Likewise, fold ((X ^ C) & C) eq/ne 0 into (X & C) ne/eq 0,
12534 when is C is a power of two, i.e. a single bit. */
12535 if (TREE_CODE (arg0) == BIT_AND_EXPR
12536 && TREE_CODE (TREE_OPERAND (arg0, 0)) == BIT_XOR_EXPR
12537 && integer_zerop (arg1)
12538 && integer_pow2p (TREE_OPERAND (arg0, 1))
12539 && operand_equal_p (TREE_OPERAND (TREE_OPERAND (arg0, 0), 1),
12540 TREE_OPERAND (arg0, 1), OEP_ONLY_CONST))
12542 tree arg000 = TREE_OPERAND (TREE_OPERAND (arg0, 0), 0);
12543 tem = fold_build2 (BIT_AND_EXPR, TREE_TYPE (arg000),
12544 arg000, TREE_OPERAND (arg0, 1));
12545 return fold_build2 (code == EQ_EXPR ? NE_EXPR : EQ_EXPR, type,
12546 tem, build_int_cst (TREE_TYPE (tem), 0));
12549 if (integer_zerop (arg1)
12550 && tree_expr_nonzero_p (arg0))
12552 tree res = constant_boolean_node (code==NE_EXPR, type);
12553 return omit_one_operand (type, res, arg0);
12556 /* Fold -X op -Y as X op Y, where op is eq/ne. */
12557 if (TREE_CODE (arg0) == NEGATE_EXPR
12558 && TREE_CODE (arg1) == NEGATE_EXPR)
12559 return fold_build2 (code, type,
12560 TREE_OPERAND (arg0, 0),
12561 TREE_OPERAND (arg1, 0));
12563 /* Fold (X & C) op (Y & C) as (X ^ Y) & C op 0", and symmetries. */
12564 if (TREE_CODE (arg0) == BIT_AND_EXPR
12565 && TREE_CODE (arg1) == BIT_AND_EXPR)
12567 tree arg00 = TREE_OPERAND (arg0, 0);
12568 tree arg01 = TREE_OPERAND (arg0, 1);
12569 tree arg10 = TREE_OPERAND (arg1, 0);
12570 tree arg11 = TREE_OPERAND (arg1, 1);
12571 tree itype = TREE_TYPE (arg0);
12573 if (operand_equal_p (arg01, arg11, 0))
12574 return fold_build2 (code, type,
12575 fold_build2 (BIT_AND_EXPR, itype,
12576 fold_build2 (BIT_XOR_EXPR, itype,
12579 build_int_cst (itype, 0));
12581 if (operand_equal_p (arg01, arg10, 0))
12582 return fold_build2 (code, type,
12583 fold_build2 (BIT_AND_EXPR, itype,
12584 fold_build2 (BIT_XOR_EXPR, itype,
12587 build_int_cst (itype, 0));
12589 if (operand_equal_p (arg00, arg11, 0))
12590 return fold_build2 (code, type,
12591 fold_build2 (BIT_AND_EXPR, itype,
12592 fold_build2 (BIT_XOR_EXPR, itype,
12595 build_int_cst (itype, 0));
12597 if (operand_equal_p (arg00, arg10, 0))
12598 return fold_build2 (code, type,
12599 fold_build2 (BIT_AND_EXPR, itype,
12600 fold_build2 (BIT_XOR_EXPR, itype,
12603 build_int_cst (itype, 0));
12606 if (TREE_CODE (arg0) == BIT_XOR_EXPR
12607 && TREE_CODE (arg1) == BIT_XOR_EXPR)
12609 tree arg00 = TREE_OPERAND (arg0, 0);
12610 tree arg01 = TREE_OPERAND (arg0, 1);
12611 tree arg10 = TREE_OPERAND (arg1, 0);
12612 tree arg11 = TREE_OPERAND (arg1, 1);
12613 tree itype = TREE_TYPE (arg0);
12615 /* Optimize (X ^ Z) op (Y ^ Z) as X op Y, and symmetries.
12616 operand_equal_p guarantees no side-effects so we don't need
12617 to use omit_one_operand on Z. */
12618 if (operand_equal_p (arg01, arg11, 0))
12619 return fold_build2 (code, type, arg00, arg10);
12620 if (operand_equal_p (arg01, arg10, 0))
12621 return fold_build2 (code, type, arg00, arg11);
12622 if (operand_equal_p (arg00, arg11, 0))
12623 return fold_build2 (code, type, arg01, arg10);
12624 if (operand_equal_p (arg00, arg10, 0))
12625 return fold_build2 (code, type, arg01, arg11);
12627 /* Optimize (X ^ C1) op (Y ^ C2) as (X ^ (C1 ^ C2)) op Y. */
12628 if (TREE_CODE (arg01) == INTEGER_CST
12629 && TREE_CODE (arg11) == INTEGER_CST)
12630 return fold_build2 (code, type,
12631 fold_build2 (BIT_XOR_EXPR, itype, arg00,
12632 fold_build2 (BIT_XOR_EXPR, itype,
12637 /* Attempt to simplify equality/inequality comparisons of complex
12638 values. Only lower the comparison if the result is known or
12639 can be simplified to a single scalar comparison. */
12640 if ((TREE_CODE (arg0) == COMPLEX_EXPR
12641 || TREE_CODE (arg0) == COMPLEX_CST)
12642 && (TREE_CODE (arg1) == COMPLEX_EXPR
12643 || TREE_CODE (arg1) == COMPLEX_CST))
12645 tree real0, imag0, real1, imag1;
12648 if (TREE_CODE (arg0) == COMPLEX_EXPR)
12650 real0 = TREE_OPERAND (arg0, 0);
12651 imag0 = TREE_OPERAND (arg0, 1);
12655 real0 = TREE_REALPART (arg0);
12656 imag0 = TREE_IMAGPART (arg0);
12659 if (TREE_CODE (arg1) == COMPLEX_EXPR)
12661 real1 = TREE_OPERAND (arg1, 0);
12662 imag1 = TREE_OPERAND (arg1, 1);
12666 real1 = TREE_REALPART (arg1);
12667 imag1 = TREE_IMAGPART (arg1);
12670 rcond = fold_binary (code, type, real0, real1);
12671 if (rcond && TREE_CODE (rcond) == INTEGER_CST)
12673 if (integer_zerop (rcond))
12675 if (code == EQ_EXPR)
12676 return omit_two_operands (type, boolean_false_node,
12678 return fold_build2 (NE_EXPR, type, imag0, imag1);
12682 if (code == NE_EXPR)
12683 return omit_two_operands (type, boolean_true_node,
12685 return fold_build2 (EQ_EXPR, type, imag0, imag1);
12689 icond = fold_binary (code, type, imag0, imag1);
12690 if (icond && TREE_CODE (icond) == INTEGER_CST)
12692 if (integer_zerop (icond))
12694 if (code == EQ_EXPR)
12695 return omit_two_operands (type, boolean_false_node,
12697 return fold_build2 (NE_EXPR, type, real0, real1);
12701 if (code == NE_EXPR)
12702 return omit_two_operands (type, boolean_true_node,
12704 return fold_build2 (EQ_EXPR, type, real0, real1);
12715 tem = fold_comparison (code, type, op0, op1);
12716 if (tem != NULL_TREE)
12719 /* Transform comparisons of the form X +- C CMP X. */
12720 if ((TREE_CODE (arg0) == PLUS_EXPR || TREE_CODE (arg0) == MINUS_EXPR)
12721 && operand_equal_p (TREE_OPERAND (arg0, 0), arg1, 0)
12722 && ((TREE_CODE (TREE_OPERAND (arg0, 1)) == REAL_CST
12723 && !HONOR_SNANS (TYPE_MODE (TREE_TYPE (arg0))))
12724 || (TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST
12725 && TYPE_OVERFLOW_UNDEFINED (TREE_TYPE (arg1)))))
12727 tree arg01 = TREE_OPERAND (arg0, 1);
12728 enum tree_code code0 = TREE_CODE (arg0);
12731 if (TREE_CODE (arg01) == REAL_CST)
12732 is_positive = REAL_VALUE_NEGATIVE (TREE_REAL_CST (arg01)) ? -1 : 1;
12734 is_positive = tree_int_cst_sgn (arg01);
12736 /* (X - c) > X becomes false. */
12737 if (code == GT_EXPR
12738 && ((code0 == MINUS_EXPR && is_positive >= 0)
12739 || (code0 == PLUS_EXPR && is_positive <= 0)))
12741 if (TREE_CODE (arg01) == INTEGER_CST
12742 && TYPE_OVERFLOW_UNDEFINED (TREE_TYPE (arg1)))
12743 fold_overflow_warning (("assuming signed overflow does not "
12744 "occur when assuming that (X - c) > X "
12745 "is always false"),
12746 WARN_STRICT_OVERFLOW_ALL);
12747 return constant_boolean_node (0, type);
12750 /* Likewise (X + c) < X becomes false. */
12751 if (code == LT_EXPR
12752 && ((code0 == PLUS_EXPR && is_positive >= 0)
12753 || (code0 == MINUS_EXPR && is_positive <= 0)))
12755 if (TREE_CODE (arg01) == INTEGER_CST
12756 && TYPE_OVERFLOW_UNDEFINED (TREE_TYPE (arg1)))
12757 fold_overflow_warning (("assuming signed overflow does not "
12758 "occur when assuming that "
12759 "(X + c) < X is always false"),
12760 WARN_STRICT_OVERFLOW_ALL);
12761 return constant_boolean_node (0, type);
12764 /* Convert (X - c) <= X to true. */
12765 if (!HONOR_NANS (TYPE_MODE (TREE_TYPE (arg1)))
12767 && ((code0 == MINUS_EXPR && is_positive >= 0)
12768 || (code0 == PLUS_EXPR && is_positive <= 0)))
12770 if (TREE_CODE (arg01) == INTEGER_CST
12771 && TYPE_OVERFLOW_UNDEFINED (TREE_TYPE (arg1)))
12772 fold_overflow_warning (("assuming signed overflow does not "
12773 "occur when assuming that "
12774 "(X - c) <= X is always true"),
12775 WARN_STRICT_OVERFLOW_ALL);
12776 return constant_boolean_node (1, type);
12779 /* Convert (X + c) >= X to true. */
12780 if (!HONOR_NANS (TYPE_MODE (TREE_TYPE (arg1)))
12782 && ((code0 == PLUS_EXPR && is_positive >= 0)
12783 || (code0 == MINUS_EXPR && is_positive <= 0)))
12785 if (TREE_CODE (arg01) == INTEGER_CST
12786 && TYPE_OVERFLOW_UNDEFINED (TREE_TYPE (arg1)))
12787 fold_overflow_warning (("assuming signed overflow does not "
12788 "occur when assuming that "
12789 "(X + c) >= X is always true"),
12790 WARN_STRICT_OVERFLOW_ALL);
12791 return constant_boolean_node (1, type);
12794 if (TREE_CODE (arg01) == INTEGER_CST)
12796 /* Convert X + c > X and X - c < X to true for integers. */
12797 if (code == GT_EXPR
12798 && ((code0 == PLUS_EXPR && is_positive > 0)
12799 || (code0 == MINUS_EXPR && is_positive < 0)))
12801 if (TYPE_OVERFLOW_UNDEFINED (TREE_TYPE (arg1)))
12802 fold_overflow_warning (("assuming signed overflow does "
12803 "not occur when assuming that "
12804 "(X + c) > X is always true"),
12805 WARN_STRICT_OVERFLOW_ALL);
12806 return constant_boolean_node (1, type);
12809 if (code == LT_EXPR
12810 && ((code0 == MINUS_EXPR && is_positive > 0)
12811 || (code0 == PLUS_EXPR && is_positive < 0)))
12813 if (TYPE_OVERFLOW_UNDEFINED (TREE_TYPE (arg1)))
12814 fold_overflow_warning (("assuming signed overflow does "
12815 "not occur when assuming that "
12816 "(X - c) < X is always true"),
12817 WARN_STRICT_OVERFLOW_ALL);
12818 return constant_boolean_node (1, type);
12821 /* Convert X + c <= X and X - c >= X to false for integers. */
12822 if (code == LE_EXPR
12823 && ((code0 == PLUS_EXPR && is_positive > 0)
12824 || (code0 == MINUS_EXPR && is_positive < 0)))
12826 if (TYPE_OVERFLOW_UNDEFINED (TREE_TYPE (arg1)))
12827 fold_overflow_warning (("assuming signed overflow does "
12828 "not occur when assuming that "
12829 "(X + c) <= X is always false"),
12830 WARN_STRICT_OVERFLOW_ALL);
12831 return constant_boolean_node (0, type);
12834 if (code == GE_EXPR
12835 && ((code0 == MINUS_EXPR && is_positive > 0)
12836 || (code0 == PLUS_EXPR && is_positive < 0)))
12838 if (TYPE_OVERFLOW_UNDEFINED (TREE_TYPE (arg1)))
12839 fold_overflow_warning (("assuming signed overflow does "
12840 "not occur when assuming that "
12841 "(X - c) >= X is always false"),
12842 WARN_STRICT_OVERFLOW_ALL);
12843 return constant_boolean_node (0, type);
12848 /* Comparisons with the highest or lowest possible integer of
12849 the specified precision will have known values. */
12851 tree arg1_type = TREE_TYPE (arg1);
12852 unsigned int width = TYPE_PRECISION (arg1_type);
12854 if (TREE_CODE (arg1) == INTEGER_CST
12855 && width <= 2 * HOST_BITS_PER_WIDE_INT
12856 && (INTEGRAL_TYPE_P (arg1_type) || POINTER_TYPE_P (arg1_type)))
12858 HOST_WIDE_INT signed_max_hi;
12859 unsigned HOST_WIDE_INT signed_max_lo;
12860 unsigned HOST_WIDE_INT max_hi, max_lo, min_hi, min_lo;
12862 if (width <= HOST_BITS_PER_WIDE_INT)
12864 signed_max_lo = ((unsigned HOST_WIDE_INT) 1 << (width - 1))
12869 if (TYPE_UNSIGNED (arg1_type))
12871 max_lo = ((unsigned HOST_WIDE_INT) 2 << (width - 1)) - 1;
12877 max_lo = signed_max_lo;
12878 min_lo = ((unsigned HOST_WIDE_INT) -1 << (width - 1));
12884 width -= HOST_BITS_PER_WIDE_INT;
12885 signed_max_lo = -1;
12886 signed_max_hi = ((unsigned HOST_WIDE_INT) 1 << (width - 1))
12891 if (TYPE_UNSIGNED (arg1_type))
12893 max_hi = ((unsigned HOST_WIDE_INT) 2 << (width - 1)) - 1;
12898 max_hi = signed_max_hi;
12899 min_hi = ((unsigned HOST_WIDE_INT) -1 << (width - 1));
12903 if ((unsigned HOST_WIDE_INT) TREE_INT_CST_HIGH (arg1) == max_hi
12904 && TREE_INT_CST_LOW (arg1) == max_lo)
12908 return omit_one_operand (type, integer_zero_node, arg0);
12911 return fold_build2 (EQ_EXPR, type, op0, op1);
12914 return omit_one_operand (type, integer_one_node, arg0);
12917 return fold_build2 (NE_EXPR, type, op0, op1);
12919 /* The GE_EXPR and LT_EXPR cases above are not normally
12920 reached because of previous transformations. */
12925 else if ((unsigned HOST_WIDE_INT) TREE_INT_CST_HIGH (arg1)
12927 && TREE_INT_CST_LOW (arg1) == max_lo - 1)
12931 arg1 = const_binop (PLUS_EXPR, arg1,
12932 build_int_cst (TREE_TYPE (arg1), 1), 0);
12933 return fold_build2 (EQ_EXPR, type,
12934 fold_convert (TREE_TYPE (arg1), arg0),
12937 arg1 = const_binop (PLUS_EXPR, arg1,
12938 build_int_cst (TREE_TYPE (arg1), 1), 0);
12939 return fold_build2 (NE_EXPR, type,
12940 fold_convert (TREE_TYPE (arg1), arg0),
12945 else if ((unsigned HOST_WIDE_INT) TREE_INT_CST_HIGH (arg1)
12947 && TREE_INT_CST_LOW (arg1) == min_lo)
12951 return omit_one_operand (type, integer_zero_node, arg0);
12954 return fold_build2 (EQ_EXPR, type, op0, op1);
12957 return omit_one_operand (type, integer_one_node, arg0);
12960 return fold_build2 (NE_EXPR, type, op0, op1);
12965 else if ((unsigned HOST_WIDE_INT) TREE_INT_CST_HIGH (arg1)
12967 && TREE_INT_CST_LOW (arg1) == min_lo + 1)
12971 arg1 = const_binop (MINUS_EXPR, arg1, integer_one_node, 0);
12972 return fold_build2 (NE_EXPR, type,
12973 fold_convert (TREE_TYPE (arg1), arg0),
12976 arg1 = const_binop (MINUS_EXPR, arg1, integer_one_node, 0);
12977 return fold_build2 (EQ_EXPR, type,
12978 fold_convert (TREE_TYPE (arg1), arg0),
12984 else if (TREE_INT_CST_HIGH (arg1) == signed_max_hi
12985 && TREE_INT_CST_LOW (arg1) == signed_max_lo
12986 && TYPE_UNSIGNED (arg1_type)
12987 /* We will flip the signedness of the comparison operator
12988 associated with the mode of arg1, so the sign bit is
12989 specified by this mode. Check that arg1 is the signed
12990 max associated with this sign bit. */
12991 && width == GET_MODE_BITSIZE (TYPE_MODE (arg1_type))
12992 /* signed_type does not work on pointer types. */
12993 && INTEGRAL_TYPE_P (arg1_type))
12995 /* The following case also applies to X < signed_max+1
12996 and X >= signed_max+1 because previous transformations. */
12997 if (code == LE_EXPR || code == GT_EXPR)
13000 st = signed_type_for (TREE_TYPE (arg1));
13001 return fold_build2 (code == LE_EXPR ? GE_EXPR : LT_EXPR,
13002 type, fold_convert (st, arg0),
13003 build_int_cst (st, 0));
13009 /* If we are comparing an ABS_EXPR with a constant, we can
13010 convert all the cases into explicit comparisons, but they may
13011 well not be faster than doing the ABS and one comparison.
13012 But ABS (X) <= C is a range comparison, which becomes a subtraction
13013 and a comparison, and is probably faster. */
13014 if (code == LE_EXPR
13015 && TREE_CODE (arg1) == INTEGER_CST
13016 && TREE_CODE (arg0) == ABS_EXPR
13017 && ! TREE_SIDE_EFFECTS (arg0)
13018 && (0 != (tem = negate_expr (arg1)))
13019 && TREE_CODE (tem) == INTEGER_CST
13020 && !TREE_OVERFLOW (tem))
13021 return fold_build2 (TRUTH_ANDIF_EXPR, type,
13022 build2 (GE_EXPR, type,
13023 TREE_OPERAND (arg0, 0), tem),
13024 build2 (LE_EXPR, type,
13025 TREE_OPERAND (arg0, 0), arg1));
13027 /* Convert ABS_EXPR<x> >= 0 to true. */
13028 strict_overflow_p = false;
13029 if (code == GE_EXPR
13030 && (integer_zerop (arg1)
13031 || (! HONOR_NANS (TYPE_MODE (TREE_TYPE (arg0)))
13032 && real_zerop (arg1)))
13033 && tree_expr_nonnegative_warnv_p (arg0, &strict_overflow_p))
13035 if (strict_overflow_p)
13036 fold_overflow_warning (("assuming signed overflow does not occur "
13037 "when simplifying comparison of "
13038 "absolute value and zero"),
13039 WARN_STRICT_OVERFLOW_CONDITIONAL);
13040 return omit_one_operand (type, integer_one_node, arg0);
13043 /* Convert ABS_EXPR<x> < 0 to false. */
13044 strict_overflow_p = false;
13045 if (code == LT_EXPR
13046 && (integer_zerop (arg1) || real_zerop (arg1))
13047 && tree_expr_nonnegative_warnv_p (arg0, &strict_overflow_p))
13049 if (strict_overflow_p)
13050 fold_overflow_warning (("assuming signed overflow does not occur "
13051 "when simplifying comparison of "
13052 "absolute value and zero"),
13053 WARN_STRICT_OVERFLOW_CONDITIONAL);
13054 return omit_one_operand (type, integer_zero_node, arg0);
13057 /* If X is unsigned, convert X < (1 << Y) into X >> Y == 0
13058 and similarly for >= into !=. */
13059 if ((code == LT_EXPR || code == GE_EXPR)
13060 && TYPE_UNSIGNED (TREE_TYPE (arg0))
13061 && TREE_CODE (arg1) == LSHIFT_EXPR
13062 && integer_onep (TREE_OPERAND (arg1, 0)))
13063 return build2 (code == LT_EXPR ? EQ_EXPR : NE_EXPR, type,
13064 build2 (RSHIFT_EXPR, TREE_TYPE (arg0), arg0,
13065 TREE_OPERAND (arg1, 1)),
13066 build_int_cst (TREE_TYPE (arg0), 0));
13068 if ((code == LT_EXPR || code == GE_EXPR)
13069 && TYPE_UNSIGNED (TREE_TYPE (arg0))
13070 && CONVERT_EXPR_P (arg1)
13071 && TREE_CODE (TREE_OPERAND (arg1, 0)) == LSHIFT_EXPR
13072 && integer_onep (TREE_OPERAND (TREE_OPERAND (arg1, 0), 0)))
13074 build2 (code == LT_EXPR ? EQ_EXPR : NE_EXPR, type,
13075 fold_convert (TREE_TYPE (arg0),
13076 build2 (RSHIFT_EXPR, TREE_TYPE (arg0), arg0,
13077 TREE_OPERAND (TREE_OPERAND (arg1, 0),
13079 build_int_cst (TREE_TYPE (arg0), 0));
13083 case UNORDERED_EXPR:
13091 if (TREE_CODE (arg0) == REAL_CST && TREE_CODE (arg1) == REAL_CST)
13093 t1 = fold_relational_const (code, type, arg0, arg1);
13094 if (t1 != NULL_TREE)
13098 /* If the first operand is NaN, the result is constant. */
13099 if (TREE_CODE (arg0) == REAL_CST
13100 && REAL_VALUE_ISNAN (TREE_REAL_CST (arg0))
13101 && (code != LTGT_EXPR || ! flag_trapping_math))
13103 t1 = (code == ORDERED_EXPR || code == LTGT_EXPR)
13104 ? integer_zero_node
13105 : integer_one_node;
13106 return omit_one_operand (type, t1, arg1);
13109 /* If the second operand is NaN, the result is constant. */
13110 if (TREE_CODE (arg1) == REAL_CST
13111 && REAL_VALUE_ISNAN (TREE_REAL_CST (arg1))
13112 && (code != LTGT_EXPR || ! flag_trapping_math))
13114 t1 = (code == ORDERED_EXPR || code == LTGT_EXPR)
13115 ? integer_zero_node
13116 : integer_one_node;
13117 return omit_one_operand (type, t1, arg0);
13120 /* Simplify unordered comparison of something with itself. */
13121 if ((code == UNLE_EXPR || code == UNGE_EXPR || code == UNEQ_EXPR)
13122 && operand_equal_p (arg0, arg1, 0))
13123 return constant_boolean_node (1, type);
13125 if (code == LTGT_EXPR
13126 && !flag_trapping_math
13127 && operand_equal_p (arg0, arg1, 0))
13128 return constant_boolean_node (0, type);
13130 /* Fold (double)float1 CMP (double)float2 into float1 CMP float2. */
13132 tree targ0 = strip_float_extensions (arg0);
13133 tree targ1 = strip_float_extensions (arg1);
13134 tree newtype = TREE_TYPE (targ0);
13136 if (TYPE_PRECISION (TREE_TYPE (targ1)) > TYPE_PRECISION (newtype))
13137 newtype = TREE_TYPE (targ1);
13139 if (TYPE_PRECISION (newtype) < TYPE_PRECISION (TREE_TYPE (arg0)))
13140 return fold_build2 (code, type, fold_convert (newtype, targ0),
13141 fold_convert (newtype, targ1));
13146 case COMPOUND_EXPR:
13147 /* When pedantic, a compound expression can be neither an lvalue
13148 nor an integer constant expression. */
13149 if (TREE_SIDE_EFFECTS (arg0) || TREE_CONSTANT (arg1))
13151 /* Don't let (0, 0) be null pointer constant. */
13152 tem = integer_zerop (arg1) ? build1 (NOP_EXPR, type, arg1)
13153 : fold_convert (type, arg1);
13154 return pedantic_non_lvalue (tem);
13157 if ((TREE_CODE (arg0) == REAL_CST
13158 && TREE_CODE (arg1) == REAL_CST)
13159 || (TREE_CODE (arg0) == INTEGER_CST
13160 && TREE_CODE (arg1) == INTEGER_CST))
13161 return build_complex (type, arg0, arg1);
13165 /* An ASSERT_EXPR should never be passed to fold_binary. */
13166 gcc_unreachable ();
13170 } /* switch (code) */
13173 /* Callback for walk_tree, looking for LABEL_EXPR.
13174 Returns tree TP if it is LABEL_EXPR. Otherwise it returns NULL_TREE.
13175 Do not check the sub-tree of GOTO_EXPR. */
13178 contains_label_1 (tree *tp,
13179 int *walk_subtrees,
13180 void *data ATTRIBUTE_UNUSED)
13182 switch (TREE_CODE (*tp))
13187 *walk_subtrees = 0;
13194 /* Checks whether the sub-tree ST contains a label LABEL_EXPR which is
13195 accessible from outside the sub-tree. Returns NULL_TREE if no
13196 addressable label is found. */
13199 contains_label_p (tree st)
13201 return (walk_tree (&st, contains_label_1 , NULL, NULL) != NULL_TREE);
13204 /* Fold a ternary expression of code CODE and type TYPE with operands
13205 OP0, OP1, and OP2. Return the folded expression if folding is
13206 successful. Otherwise, return NULL_TREE. */
13209 fold_ternary (enum tree_code code, tree type, tree op0, tree op1, tree op2)
13212 tree arg0 = NULL_TREE, arg1 = NULL_TREE;
13213 enum tree_code_class kind = TREE_CODE_CLASS (code);
13215 gcc_assert (IS_EXPR_CODE_CLASS (kind)
13216 && TREE_CODE_LENGTH (code) == 3);
13218 /* Strip any conversions that don't change the mode. This is safe
13219 for every expression, except for a comparison expression because
13220 its signedness is derived from its operands. So, in the latter
13221 case, only strip conversions that don't change the signedness.
13223 Note that this is done as an internal manipulation within the
13224 constant folder, in order to find the simplest representation of
13225 the arguments so that their form can be studied. In any cases,
13226 the appropriate type conversions should be put back in the tree
13227 that will get out of the constant folder. */
13242 case COMPONENT_REF:
13243 if (TREE_CODE (arg0) == CONSTRUCTOR
13244 && ! type_contains_placeholder_p (TREE_TYPE (arg0)))
13246 unsigned HOST_WIDE_INT idx;
13248 FOR_EACH_CONSTRUCTOR_ELT (CONSTRUCTOR_ELTS (arg0), idx, field, value)
13255 /* Pedantic ANSI C says that a conditional expression is never an lvalue,
13256 so all simple results must be passed through pedantic_non_lvalue. */
13257 if (TREE_CODE (arg0) == INTEGER_CST)
13259 tree unused_op = integer_zerop (arg0) ? op1 : op2;
13260 tem = integer_zerop (arg0) ? op2 : op1;
13261 /* Only optimize constant conditions when the selected branch
13262 has the same type as the COND_EXPR. This avoids optimizing
13263 away "c ? x : throw", where the throw has a void type.
13264 Avoid throwing away that operand which contains label. */
13265 if ((!TREE_SIDE_EFFECTS (unused_op)
13266 || !contains_label_p (unused_op))
13267 && (! VOID_TYPE_P (TREE_TYPE (tem))
13268 || VOID_TYPE_P (type)))
13269 return pedantic_non_lvalue (tem);
13272 if (operand_equal_p (arg1, op2, 0))
13273 return pedantic_omit_one_operand (type, arg1, arg0);
13275 /* If we have A op B ? A : C, we may be able to convert this to a
13276 simpler expression, depending on the operation and the values
13277 of B and C. Signed zeros prevent all of these transformations,
13278 for reasons given above each one.
13280 Also try swapping the arguments and inverting the conditional. */
13281 if (COMPARISON_CLASS_P (arg0)
13282 && operand_equal_for_comparison_p (TREE_OPERAND (arg0, 0),
13283 arg1, TREE_OPERAND (arg0, 1))
13284 && !HONOR_SIGNED_ZEROS (TYPE_MODE (TREE_TYPE (arg1))))
13286 tem = fold_cond_expr_with_comparison (type, arg0, op1, op2);
13291 if (COMPARISON_CLASS_P (arg0)
13292 && operand_equal_for_comparison_p (TREE_OPERAND (arg0, 0),
13294 TREE_OPERAND (arg0, 1))
13295 && !HONOR_SIGNED_ZEROS (TYPE_MODE (TREE_TYPE (op2))))
13297 tem = fold_truth_not_expr (arg0);
13298 if (tem && COMPARISON_CLASS_P (tem))
13300 tem = fold_cond_expr_with_comparison (type, tem, op2, op1);
13306 /* If the second operand is simpler than the third, swap them
13307 since that produces better jump optimization results. */
13308 if (truth_value_p (TREE_CODE (arg0))
13309 && tree_swap_operands_p (op1, op2, false))
13311 /* See if this can be inverted. If it can't, possibly because
13312 it was a floating-point inequality comparison, don't do
13314 tem = fold_truth_not_expr (arg0);
13316 return fold_build3 (code, type, tem, op2, op1);
13319 /* Convert A ? 1 : 0 to simply A. */
13320 if (integer_onep (op1)
13321 && integer_zerop (op2)
13322 /* If we try to convert OP0 to our type, the
13323 call to fold will try to move the conversion inside
13324 a COND, which will recurse. In that case, the COND_EXPR
13325 is probably the best choice, so leave it alone. */
13326 && type == TREE_TYPE (arg0))
13327 return pedantic_non_lvalue (arg0);
13329 /* Convert A ? 0 : 1 to !A. This prefers the use of NOT_EXPR
13330 over COND_EXPR in cases such as floating point comparisons. */
13331 if (integer_zerop (op1)
13332 && integer_onep (op2)
13333 && truth_value_p (TREE_CODE (arg0)))
13334 return pedantic_non_lvalue (fold_convert (type,
13335 invert_truthvalue (arg0)));
13337 /* A < 0 ? <sign bit of A> : 0 is simply (A & <sign bit of A>). */
13338 if (TREE_CODE (arg0) == LT_EXPR
13339 && integer_zerop (TREE_OPERAND (arg0, 1))
13340 && integer_zerop (op2)
13341 && (tem = sign_bit_p (TREE_OPERAND (arg0, 0), arg1)))
13343 /* sign_bit_p only checks ARG1 bits within A's precision.
13344 If <sign bit of A> has wider type than A, bits outside
13345 of A's precision in <sign bit of A> need to be checked.
13346 If they are all 0, this optimization needs to be done
13347 in unsigned A's type, if they are all 1 in signed A's type,
13348 otherwise this can't be done. */
13349 if (TYPE_PRECISION (TREE_TYPE (tem))
13350 < TYPE_PRECISION (TREE_TYPE (arg1))
13351 && TYPE_PRECISION (TREE_TYPE (tem))
13352 < TYPE_PRECISION (type))
13354 unsigned HOST_WIDE_INT mask_lo;
13355 HOST_WIDE_INT mask_hi;
13356 int inner_width, outer_width;
13359 inner_width = TYPE_PRECISION (TREE_TYPE (tem));
13360 outer_width = TYPE_PRECISION (TREE_TYPE (arg1));
13361 if (outer_width > TYPE_PRECISION (type))
13362 outer_width = TYPE_PRECISION (type);
13364 if (outer_width > HOST_BITS_PER_WIDE_INT)
13366 mask_hi = ((unsigned HOST_WIDE_INT) -1
13367 >> (2 * HOST_BITS_PER_WIDE_INT - outer_width));
13373 mask_lo = ((unsigned HOST_WIDE_INT) -1
13374 >> (HOST_BITS_PER_WIDE_INT - outer_width));
13376 if (inner_width > HOST_BITS_PER_WIDE_INT)
13378 mask_hi &= ~((unsigned HOST_WIDE_INT) -1
13379 >> (HOST_BITS_PER_WIDE_INT - inner_width));
13383 mask_lo &= ~((unsigned HOST_WIDE_INT) -1
13384 >> (HOST_BITS_PER_WIDE_INT - inner_width));
13386 if ((TREE_INT_CST_HIGH (arg1) & mask_hi) == mask_hi
13387 && (TREE_INT_CST_LOW (arg1) & mask_lo) == mask_lo)
13389 tem_type = signed_type_for (TREE_TYPE (tem));
13390 tem = fold_convert (tem_type, tem);
13392 else if ((TREE_INT_CST_HIGH (arg1) & mask_hi) == 0
13393 && (TREE_INT_CST_LOW (arg1) & mask_lo) == 0)
13395 tem_type = unsigned_type_for (TREE_TYPE (tem));
13396 tem = fold_convert (tem_type, tem);
13403 return fold_convert (type,
13404 fold_build2 (BIT_AND_EXPR,
13405 TREE_TYPE (tem), tem,
13406 fold_convert (TREE_TYPE (tem),
13410 /* (A >> N) & 1 ? (1 << N) : 0 is simply A & (1 << N). A & 1 was
13411 already handled above. */
13412 if (TREE_CODE (arg0) == BIT_AND_EXPR
13413 && integer_onep (TREE_OPERAND (arg0, 1))
13414 && integer_zerop (op2)
13415 && integer_pow2p (arg1))
13417 tree tem = TREE_OPERAND (arg0, 0);
13419 if (TREE_CODE (tem) == RSHIFT_EXPR
13420 && TREE_CODE (TREE_OPERAND (tem, 1)) == INTEGER_CST
13421 && (unsigned HOST_WIDE_INT) tree_log2 (arg1) ==
13422 TREE_INT_CST_LOW (TREE_OPERAND (tem, 1)))
13423 return fold_build2 (BIT_AND_EXPR, type,
13424 TREE_OPERAND (tem, 0), arg1);
13427 /* A & N ? N : 0 is simply A & N if N is a power of two. This
13428 is probably obsolete because the first operand should be a
13429 truth value (that's why we have the two cases above), but let's
13430 leave it in until we can confirm this for all front-ends. */
13431 if (integer_zerop (op2)
13432 && TREE_CODE (arg0) == NE_EXPR
13433 && integer_zerop (TREE_OPERAND (arg0, 1))
13434 && integer_pow2p (arg1)
13435 && TREE_CODE (TREE_OPERAND (arg0, 0)) == BIT_AND_EXPR
13436 && operand_equal_p (TREE_OPERAND (TREE_OPERAND (arg0, 0), 1),
13437 arg1, OEP_ONLY_CONST))
13438 return pedantic_non_lvalue (fold_convert (type,
13439 TREE_OPERAND (arg0, 0)));
13441 /* Convert A ? B : 0 into A && B if A and B are truth values. */
13442 if (integer_zerop (op2)
13443 && truth_value_p (TREE_CODE (arg0))
13444 && truth_value_p (TREE_CODE (arg1)))
13445 return fold_build2 (TRUTH_ANDIF_EXPR, type,
13446 fold_convert (type, arg0),
13449 /* Convert A ? B : 1 into !A || B if A and B are truth values. */
13450 if (integer_onep (op2)
13451 && truth_value_p (TREE_CODE (arg0))
13452 && truth_value_p (TREE_CODE (arg1)))
13454 /* Only perform transformation if ARG0 is easily inverted. */
13455 tem = fold_truth_not_expr (arg0);
13457 return fold_build2 (TRUTH_ORIF_EXPR, type,
13458 fold_convert (type, tem),
13462 /* Convert A ? 0 : B into !A && B if A and B are truth values. */
13463 if (integer_zerop (arg1)
13464 && truth_value_p (TREE_CODE (arg0))
13465 && truth_value_p (TREE_CODE (op2)))
13467 /* Only perform transformation if ARG0 is easily inverted. */
13468 tem = fold_truth_not_expr (arg0);
13470 return fold_build2 (TRUTH_ANDIF_EXPR, type,
13471 fold_convert (type, tem),
13475 /* Convert A ? 1 : B into A || B if A and B are truth values. */
13476 if (integer_onep (arg1)
13477 && truth_value_p (TREE_CODE (arg0))
13478 && truth_value_p (TREE_CODE (op2)))
13479 return fold_build2 (TRUTH_ORIF_EXPR, type,
13480 fold_convert (type, arg0),
13486 /* CALL_EXPRs used to be ternary exprs. Catch any mistaken uses
13487 of fold_ternary on them. */
13488 gcc_unreachable ();
13490 case BIT_FIELD_REF:
13491 if ((TREE_CODE (arg0) == VECTOR_CST
13492 || (TREE_CODE (arg0) == CONSTRUCTOR && TREE_CONSTANT (arg0)))
13493 && type == TREE_TYPE (TREE_TYPE (arg0)))
13495 unsigned HOST_WIDE_INT width = tree_low_cst (arg1, 1);
13496 unsigned HOST_WIDE_INT idx = tree_low_cst (op2, 1);
13499 && simple_cst_equal (arg1, TYPE_SIZE (type)) == 1
13500 && (idx % width) == 0
13501 && (idx = idx / width)
13502 < TYPE_VECTOR_SUBPARTS (TREE_TYPE (arg0)))
13504 tree elements = NULL_TREE;
13506 if (TREE_CODE (arg0) == VECTOR_CST)
13507 elements = TREE_VECTOR_CST_ELTS (arg0);
13510 unsigned HOST_WIDE_INT idx;
13513 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (arg0), idx, value)
13514 elements = tree_cons (NULL_TREE, value, elements);
13516 while (idx-- > 0 && elements)
13517 elements = TREE_CHAIN (elements);
13519 return TREE_VALUE (elements);
13521 return fold_convert (type, integer_zero_node);
13525 /* A bit-field-ref that referenced the full argument can be stripped. */
13526 if (INTEGRAL_TYPE_P (TREE_TYPE (arg0))
13527 && TYPE_PRECISION (TREE_TYPE (arg0)) == tree_low_cst (arg1, 1)
13528 && integer_zerop (op2))
13529 return fold_convert (type, arg0);
13535 } /* switch (code) */
13538 /* Perform constant folding and related simplification of EXPR.
13539 The related simplifications include x*1 => x, x*0 => 0, etc.,
13540 and application of the associative law.
13541 NOP_EXPR conversions may be removed freely (as long as we
13542 are careful not to change the type of the overall expression).
13543 We cannot simplify through a CONVERT_EXPR, FIX_EXPR or FLOAT_EXPR,
13544 but we can constant-fold them if they have constant operands. */
13546 #ifdef ENABLE_FOLD_CHECKING
13547 # define fold(x) fold_1 (x)
13548 static tree fold_1 (tree);
13554 const tree t = expr;
13555 enum tree_code code = TREE_CODE (t);
13556 enum tree_code_class kind = TREE_CODE_CLASS (code);
13559 /* Return right away if a constant. */
13560 if (kind == tcc_constant)
13563 /* CALL_EXPR-like objects with variable numbers of operands are
13564 treated specially. */
13565 if (kind == tcc_vl_exp)
13567 if (code == CALL_EXPR)
13569 tem = fold_call_expr (expr, false);
13570 return tem ? tem : expr;
13575 if (IS_EXPR_CODE_CLASS (kind))
13577 tree type = TREE_TYPE (t);
13578 tree op0, op1, op2;
13580 switch (TREE_CODE_LENGTH (code))
13583 op0 = TREE_OPERAND (t, 0);
13584 tem = fold_unary (code, type, op0);
13585 return tem ? tem : expr;
13587 op0 = TREE_OPERAND (t, 0);
13588 op1 = TREE_OPERAND (t, 1);
13589 tem = fold_binary (code, type, op0, op1);
13590 return tem ? tem : expr;
13592 op0 = TREE_OPERAND (t, 0);
13593 op1 = TREE_OPERAND (t, 1);
13594 op2 = TREE_OPERAND (t, 2);
13595 tem = fold_ternary (code, type, op0, op1, op2);
13596 return tem ? tem : expr;
13606 tree op0 = TREE_OPERAND (t, 0);
13607 tree op1 = TREE_OPERAND (t, 1);
13609 if (TREE_CODE (op1) == INTEGER_CST
13610 && TREE_CODE (op0) == CONSTRUCTOR
13611 && ! type_contains_placeholder_p (TREE_TYPE (op0)))
13613 VEC(constructor_elt,gc) *elts = CONSTRUCTOR_ELTS (op0);
13614 unsigned HOST_WIDE_INT end = VEC_length (constructor_elt, elts);
13615 unsigned HOST_WIDE_INT begin = 0;
13617 /* Find a matching index by means of a binary search. */
13618 while (begin != end)
13620 unsigned HOST_WIDE_INT middle = (begin + end) / 2;
13621 tree index = VEC_index (constructor_elt, elts, middle)->index;
13623 if (TREE_CODE (index) == INTEGER_CST
13624 && tree_int_cst_lt (index, op1))
13625 begin = middle + 1;
13626 else if (TREE_CODE (index) == INTEGER_CST
13627 && tree_int_cst_lt (op1, index))
13629 else if (TREE_CODE (index) == RANGE_EXPR
13630 && tree_int_cst_lt (TREE_OPERAND (index, 1), op1))
13631 begin = middle + 1;
13632 else if (TREE_CODE (index) == RANGE_EXPR
13633 && tree_int_cst_lt (op1, TREE_OPERAND (index, 0)))
13636 return VEC_index (constructor_elt, elts, middle)->value;
13644 return fold (DECL_INITIAL (t));
13648 } /* switch (code) */
13651 #ifdef ENABLE_FOLD_CHECKING
13654 static void fold_checksum_tree (const_tree, struct md5_ctx *, htab_t);
13655 static void fold_check_failed (const_tree, const_tree);
13656 void print_fold_checksum (const_tree);
13658 /* When --enable-checking=fold, compute a digest of expr before
13659 and after actual fold call to see if fold did not accidentally
13660 change original expr. */
13666 struct md5_ctx ctx;
13667 unsigned char checksum_before[16], checksum_after[16];
13670 ht = htab_create (32, htab_hash_pointer, htab_eq_pointer, NULL);
13671 md5_init_ctx (&ctx);
13672 fold_checksum_tree (expr, &ctx, ht);
13673 md5_finish_ctx (&ctx, checksum_before);
13676 ret = fold_1 (expr);
13678 md5_init_ctx (&ctx);
13679 fold_checksum_tree (expr, &ctx, ht);
13680 md5_finish_ctx (&ctx, checksum_after);
13683 if (memcmp (checksum_before, checksum_after, 16))
13684 fold_check_failed (expr, ret);
13690 print_fold_checksum (const_tree expr)
13692 struct md5_ctx ctx;
13693 unsigned char checksum[16], cnt;
13696 ht = htab_create (32, htab_hash_pointer, htab_eq_pointer, NULL);
13697 md5_init_ctx (&ctx);
13698 fold_checksum_tree (expr, &ctx, ht);
13699 md5_finish_ctx (&ctx, checksum);
13701 for (cnt = 0; cnt < 16; ++cnt)
13702 fprintf (stderr, "%02x", checksum[cnt]);
13703 putc ('\n', stderr);
13707 fold_check_failed (const_tree expr ATTRIBUTE_UNUSED, const_tree ret ATTRIBUTE_UNUSED)
13709 internal_error ("fold check: original tree changed by fold");
13713 fold_checksum_tree (const_tree expr, struct md5_ctx *ctx, htab_t ht)
13716 enum tree_code code;
13717 union tree_node buf;
13722 gcc_assert ((sizeof (struct tree_exp) + 5 * sizeof (tree)
13723 <= sizeof (struct tree_function_decl))
13724 && sizeof (struct tree_type) <= sizeof (struct tree_function_decl));
13727 slot = (const void **) htab_find_slot (ht, expr, INSERT);
13731 code = TREE_CODE (expr);
13732 if (TREE_CODE_CLASS (code) == tcc_declaration
13733 && DECL_ASSEMBLER_NAME_SET_P (expr))
13735 /* Allow DECL_ASSEMBLER_NAME to be modified. */
13736 memcpy ((char *) &buf, expr, tree_size (expr));
13737 SET_DECL_ASSEMBLER_NAME ((tree)&buf, NULL);
13738 expr = (tree) &buf;
13740 else if (TREE_CODE_CLASS (code) == tcc_type
13741 && (TYPE_POINTER_TO (expr)
13742 || TYPE_REFERENCE_TO (expr)
13743 || TYPE_CACHED_VALUES_P (expr)
13744 || TYPE_CONTAINS_PLACEHOLDER_INTERNAL (expr)
13745 || TYPE_NEXT_VARIANT (expr)))
13747 /* Allow these fields to be modified. */
13749 memcpy ((char *) &buf, expr, tree_size (expr));
13750 expr = tmp = (tree) &buf;
13751 TYPE_CONTAINS_PLACEHOLDER_INTERNAL (tmp) = 0;
13752 TYPE_POINTER_TO (tmp) = NULL;
13753 TYPE_REFERENCE_TO (tmp) = NULL;
13754 TYPE_NEXT_VARIANT (tmp) = NULL;
13755 if (TYPE_CACHED_VALUES_P (tmp))
13757 TYPE_CACHED_VALUES_P (tmp) = 0;
13758 TYPE_CACHED_VALUES (tmp) = NULL;
13761 md5_process_bytes (expr, tree_size (expr), ctx);
13762 fold_checksum_tree (TREE_TYPE (expr), ctx, ht);
13763 if (TREE_CODE_CLASS (code) != tcc_type
13764 && TREE_CODE_CLASS (code) != tcc_declaration
13765 && code != TREE_LIST
13766 && code != SSA_NAME)
13767 fold_checksum_tree (TREE_CHAIN (expr), ctx, ht);
13768 switch (TREE_CODE_CLASS (code))
13774 md5_process_bytes (TREE_STRING_POINTER (expr),
13775 TREE_STRING_LENGTH (expr), ctx);
13778 fold_checksum_tree (TREE_REALPART (expr), ctx, ht);
13779 fold_checksum_tree (TREE_IMAGPART (expr), ctx, ht);
13782 fold_checksum_tree (TREE_VECTOR_CST_ELTS (expr), ctx, ht);
13788 case tcc_exceptional:
13792 fold_checksum_tree (TREE_PURPOSE (expr), ctx, ht);
13793 fold_checksum_tree (TREE_VALUE (expr), ctx, ht);
13794 expr = TREE_CHAIN (expr);
13795 goto recursive_label;
13798 for (i = 0; i < TREE_VEC_LENGTH (expr); ++i)
13799 fold_checksum_tree (TREE_VEC_ELT (expr, i), ctx, ht);
13805 case tcc_expression:
13806 case tcc_reference:
13807 case tcc_comparison:
13810 case tcc_statement:
13812 len = TREE_OPERAND_LENGTH (expr);
13813 for (i = 0; i < len; ++i)
13814 fold_checksum_tree (TREE_OPERAND (expr, i), ctx, ht);
13816 case tcc_declaration:
13817 fold_checksum_tree (DECL_NAME (expr), ctx, ht);
13818 fold_checksum_tree (DECL_CONTEXT (expr), ctx, ht);
13819 if (CODE_CONTAINS_STRUCT (TREE_CODE (expr), TS_DECL_COMMON))
13821 fold_checksum_tree (DECL_SIZE (expr), ctx, ht);
13822 fold_checksum_tree (DECL_SIZE_UNIT (expr), ctx, ht);
13823 fold_checksum_tree (DECL_INITIAL (expr), ctx, ht);
13824 fold_checksum_tree (DECL_ABSTRACT_ORIGIN (expr), ctx, ht);
13825 fold_checksum_tree (DECL_ATTRIBUTES (expr), ctx, ht);
13827 if (CODE_CONTAINS_STRUCT (TREE_CODE (expr), TS_DECL_WITH_VIS))
13828 fold_checksum_tree (DECL_SECTION_NAME (expr), ctx, ht);
13830 if (CODE_CONTAINS_STRUCT (TREE_CODE (expr), TS_DECL_NON_COMMON))
13832 fold_checksum_tree (DECL_VINDEX (expr), ctx, ht);
13833 fold_checksum_tree (DECL_RESULT_FLD (expr), ctx, ht);
13834 fold_checksum_tree (DECL_ARGUMENT_FLD (expr), ctx, ht);
13838 if (TREE_CODE (expr) == ENUMERAL_TYPE)
13839 fold_checksum_tree (TYPE_VALUES (expr), ctx, ht);
13840 fold_checksum_tree (TYPE_SIZE (expr), ctx, ht);
13841 fold_checksum_tree (TYPE_SIZE_UNIT (expr), ctx, ht);
13842 fold_checksum_tree (TYPE_ATTRIBUTES (expr), ctx, ht);
13843 fold_checksum_tree (TYPE_NAME (expr), ctx, ht);
13844 if (INTEGRAL_TYPE_P (expr)
13845 || SCALAR_FLOAT_TYPE_P (expr))
13847 fold_checksum_tree (TYPE_MIN_VALUE (expr), ctx, ht);
13848 fold_checksum_tree (TYPE_MAX_VALUE (expr), ctx, ht);
13850 fold_checksum_tree (TYPE_MAIN_VARIANT (expr), ctx, ht);
13851 if (TREE_CODE (expr) == RECORD_TYPE
13852 || TREE_CODE (expr) == UNION_TYPE
13853 || TREE_CODE (expr) == QUAL_UNION_TYPE)
13854 fold_checksum_tree (TYPE_BINFO (expr), ctx, ht);
13855 fold_checksum_tree (TYPE_CONTEXT (expr), ctx, ht);
13862 /* Helper function for outputting the checksum of a tree T. When
13863 debugging with gdb, you can "define mynext" to be "next" followed
13864 by "call debug_fold_checksum (op0)", then just trace down till the
13868 debug_fold_checksum (const_tree t)
13871 unsigned char checksum[16];
13872 struct md5_ctx ctx;
13873 htab_t ht = htab_create (32, htab_hash_pointer, htab_eq_pointer, NULL);
13875 md5_init_ctx (&ctx);
13876 fold_checksum_tree (t, &ctx, ht);
13877 md5_finish_ctx (&ctx, checksum);
13880 for (i = 0; i < 16; i++)
13881 fprintf (stderr, "%d ", checksum[i]);
13883 fprintf (stderr, "\n");
13888 /* Fold a unary tree expression with code CODE of type TYPE with an
13889 operand OP0. Return a folded expression if successful. Otherwise,
13890 return a tree expression with code CODE of type TYPE with an
13894 fold_build1_stat (enum tree_code code, tree type, tree op0 MEM_STAT_DECL)
13897 #ifdef ENABLE_FOLD_CHECKING
13898 unsigned char checksum_before[16], checksum_after[16];
13899 struct md5_ctx ctx;
13902 ht = htab_create (32, htab_hash_pointer, htab_eq_pointer, NULL);
13903 md5_init_ctx (&ctx);
13904 fold_checksum_tree (op0, &ctx, ht);
13905 md5_finish_ctx (&ctx, checksum_before);
13909 tem = fold_unary (code, type, op0);
13911 tem = build1_stat (code, type, op0 PASS_MEM_STAT);
13913 #ifdef ENABLE_FOLD_CHECKING
13914 md5_init_ctx (&ctx);
13915 fold_checksum_tree (op0, &ctx, ht);
13916 md5_finish_ctx (&ctx, checksum_after);
13919 if (memcmp (checksum_before, checksum_after, 16))
13920 fold_check_failed (op0, tem);
13925 /* Fold a binary tree expression with code CODE of type TYPE with
13926 operands OP0 and OP1. Return a folded expression if successful.
13927 Otherwise, return a tree expression with code CODE of type TYPE
13928 with operands OP0 and OP1. */
13931 fold_build2_stat (enum tree_code code, tree type, tree op0, tree op1
13935 #ifdef ENABLE_FOLD_CHECKING
13936 unsigned char checksum_before_op0[16],
13937 checksum_before_op1[16],
13938 checksum_after_op0[16],
13939 checksum_after_op1[16];
13940 struct md5_ctx ctx;
13943 ht = htab_create (32, htab_hash_pointer, htab_eq_pointer, NULL);
13944 md5_init_ctx (&ctx);
13945 fold_checksum_tree (op0, &ctx, ht);
13946 md5_finish_ctx (&ctx, checksum_before_op0);
13949 md5_init_ctx (&ctx);
13950 fold_checksum_tree (op1, &ctx, ht);
13951 md5_finish_ctx (&ctx, checksum_before_op1);
13955 tem = fold_binary (code, type, op0, op1);
13957 tem = build2_stat (code, type, op0, op1 PASS_MEM_STAT);
13959 #ifdef ENABLE_FOLD_CHECKING
13960 md5_init_ctx (&ctx);
13961 fold_checksum_tree (op0, &ctx, ht);
13962 md5_finish_ctx (&ctx, checksum_after_op0);
13965 if (memcmp (checksum_before_op0, checksum_after_op0, 16))
13966 fold_check_failed (op0, tem);
13968 md5_init_ctx (&ctx);
13969 fold_checksum_tree (op1, &ctx, ht);
13970 md5_finish_ctx (&ctx, checksum_after_op1);
13973 if (memcmp (checksum_before_op1, checksum_after_op1, 16))
13974 fold_check_failed (op1, tem);
13979 /* Fold a ternary tree expression with code CODE of type TYPE with
13980 operands OP0, OP1, and OP2. Return a folded expression if
13981 successful. Otherwise, return a tree expression with code CODE of
13982 type TYPE with operands OP0, OP1, and OP2. */
13985 fold_build3_stat (enum tree_code code, tree type, tree op0, tree op1, tree op2
13989 #ifdef ENABLE_FOLD_CHECKING
13990 unsigned char checksum_before_op0[16],
13991 checksum_before_op1[16],
13992 checksum_before_op2[16],
13993 checksum_after_op0[16],
13994 checksum_after_op1[16],
13995 checksum_after_op2[16];
13996 struct md5_ctx ctx;
13999 ht = htab_create (32, htab_hash_pointer, htab_eq_pointer, NULL);
14000 md5_init_ctx (&ctx);
14001 fold_checksum_tree (op0, &ctx, ht);
14002 md5_finish_ctx (&ctx, checksum_before_op0);
14005 md5_init_ctx (&ctx);
14006 fold_checksum_tree (op1, &ctx, ht);
14007 md5_finish_ctx (&ctx, checksum_before_op1);
14010 md5_init_ctx (&ctx);
14011 fold_checksum_tree (op2, &ctx, ht);
14012 md5_finish_ctx (&ctx, checksum_before_op2);
14016 gcc_assert (TREE_CODE_CLASS (code) != tcc_vl_exp);
14017 tem = fold_ternary (code, type, op0, op1, op2);
14019 tem = build3_stat (code, type, op0, op1, op2 PASS_MEM_STAT);
14021 #ifdef ENABLE_FOLD_CHECKING
14022 md5_init_ctx (&ctx);
14023 fold_checksum_tree (op0, &ctx, ht);
14024 md5_finish_ctx (&ctx, checksum_after_op0);
14027 if (memcmp (checksum_before_op0, checksum_after_op0, 16))
14028 fold_check_failed (op0, tem);
14030 md5_init_ctx (&ctx);
14031 fold_checksum_tree (op1, &ctx, ht);
14032 md5_finish_ctx (&ctx, checksum_after_op1);
14035 if (memcmp (checksum_before_op1, checksum_after_op1, 16))
14036 fold_check_failed (op1, tem);
14038 md5_init_ctx (&ctx);
14039 fold_checksum_tree (op2, &ctx, ht);
14040 md5_finish_ctx (&ctx, checksum_after_op2);
14043 if (memcmp (checksum_before_op2, checksum_after_op2, 16))
14044 fold_check_failed (op2, tem);
14049 /* Fold a CALL_EXPR expression of type TYPE with operands FN and NARGS
14050 arguments in ARGARRAY, and a null static chain.
14051 Return a folded expression if successful. Otherwise, return a CALL_EXPR
14052 of type TYPE from the given operands as constructed by build_call_array. */
14055 fold_build_call_array (tree type, tree fn, int nargs, tree *argarray)
14058 #ifdef ENABLE_FOLD_CHECKING
14059 unsigned char checksum_before_fn[16],
14060 checksum_before_arglist[16],
14061 checksum_after_fn[16],
14062 checksum_after_arglist[16];
14063 struct md5_ctx ctx;
14067 ht = htab_create (32, htab_hash_pointer, htab_eq_pointer, NULL);
14068 md5_init_ctx (&ctx);
14069 fold_checksum_tree (fn, &ctx, ht);
14070 md5_finish_ctx (&ctx, checksum_before_fn);
14073 md5_init_ctx (&ctx);
14074 for (i = 0; i < nargs; i++)
14075 fold_checksum_tree (argarray[i], &ctx, ht);
14076 md5_finish_ctx (&ctx, checksum_before_arglist);
14080 tem = fold_builtin_call_array (type, fn, nargs, argarray);
14082 #ifdef ENABLE_FOLD_CHECKING
14083 md5_init_ctx (&ctx);
14084 fold_checksum_tree (fn, &ctx, ht);
14085 md5_finish_ctx (&ctx, checksum_after_fn);
14088 if (memcmp (checksum_before_fn, checksum_after_fn, 16))
14089 fold_check_failed (fn, tem);
14091 md5_init_ctx (&ctx);
14092 for (i = 0; i < nargs; i++)
14093 fold_checksum_tree (argarray[i], &ctx, ht);
14094 md5_finish_ctx (&ctx, checksum_after_arglist);
14097 if (memcmp (checksum_before_arglist, checksum_after_arglist, 16))
14098 fold_check_failed (NULL_TREE, tem);
14103 /* Perform constant folding and related simplification of initializer
14104 expression EXPR. These behave identically to "fold_buildN" but ignore
14105 potential run-time traps and exceptions that fold must preserve. */
14107 #define START_FOLD_INIT \
14108 int saved_signaling_nans = flag_signaling_nans;\
14109 int saved_trapping_math = flag_trapping_math;\
14110 int saved_rounding_math = flag_rounding_math;\
14111 int saved_trapv = flag_trapv;\
14112 int saved_folding_initializer = folding_initializer;\
14113 flag_signaling_nans = 0;\
14114 flag_trapping_math = 0;\
14115 flag_rounding_math = 0;\
14117 folding_initializer = 1;
14119 #define END_FOLD_INIT \
14120 flag_signaling_nans = saved_signaling_nans;\
14121 flag_trapping_math = saved_trapping_math;\
14122 flag_rounding_math = saved_rounding_math;\
14123 flag_trapv = saved_trapv;\
14124 folding_initializer = saved_folding_initializer;
14127 fold_build1_initializer (enum tree_code code, tree type, tree op)
14132 result = fold_build1 (code, type, op);
14139 fold_build2_initializer (enum tree_code code, tree type, tree op0, tree op1)
14144 result = fold_build2 (code, type, op0, op1);
14151 fold_build3_initializer (enum tree_code code, tree type, tree op0, tree op1,
14157 result = fold_build3 (code, type, op0, op1, op2);
14164 fold_build_call_array_initializer (tree type, tree fn,
14165 int nargs, tree *argarray)
14170 result = fold_build_call_array (type, fn, nargs, argarray);
14176 #undef START_FOLD_INIT
14177 #undef END_FOLD_INIT
14179 /* Determine if first argument is a multiple of second argument. Return 0 if
14180 it is not, or we cannot easily determined it to be.
14182 An example of the sort of thing we care about (at this point; this routine
14183 could surely be made more general, and expanded to do what the *_DIV_EXPR's
14184 fold cases do now) is discovering that
14186 SAVE_EXPR (I) * SAVE_EXPR (J * 8)
14192 when we know that the two SAVE_EXPR (J * 8) nodes are the same node.
14194 This code also handles discovering that
14196 SAVE_EXPR (I) * SAVE_EXPR (J * 8)
14198 is a multiple of 8 so we don't have to worry about dealing with a
14199 possible remainder.
14201 Note that we *look* inside a SAVE_EXPR only to determine how it was
14202 calculated; it is not safe for fold to do much of anything else with the
14203 internals of a SAVE_EXPR, since it cannot know when it will be evaluated
14204 at run time. For example, the latter example above *cannot* be implemented
14205 as SAVE_EXPR (I) * J or any variant thereof, since the value of J at
14206 evaluation time of the original SAVE_EXPR is not necessarily the same at
14207 the time the new expression is evaluated. The only optimization of this
14208 sort that would be valid is changing
14210 SAVE_EXPR (I) * SAVE_EXPR (SAVE_EXPR (J) * 8)
14214 SAVE_EXPR (I) * SAVE_EXPR (J)
14216 (where the same SAVE_EXPR (J) is used in the original and the
14217 transformed version). */
14220 multiple_of_p (tree type, const_tree top, const_tree bottom)
14222 if (operand_equal_p (top, bottom, 0))
14225 if (TREE_CODE (type) != INTEGER_TYPE)
14228 switch (TREE_CODE (top))
14231 /* Bitwise and provides a power of two multiple. If the mask is
14232 a multiple of BOTTOM then TOP is a multiple of BOTTOM. */
14233 if (!integer_pow2p (bottom))
14238 return (multiple_of_p (type, TREE_OPERAND (top, 0), bottom)
14239 || multiple_of_p (type, TREE_OPERAND (top, 1), bottom));
14243 return (multiple_of_p (type, TREE_OPERAND (top, 0), bottom)
14244 && multiple_of_p (type, TREE_OPERAND (top, 1), bottom));
14247 if (TREE_CODE (TREE_OPERAND (top, 1)) == INTEGER_CST)
14251 op1 = TREE_OPERAND (top, 1);
14252 /* const_binop may not detect overflow correctly,
14253 so check for it explicitly here. */
14254 if (TYPE_PRECISION (TREE_TYPE (size_one_node))
14255 > TREE_INT_CST_LOW (op1)
14256 && TREE_INT_CST_HIGH (op1) == 0
14257 && 0 != (t1 = fold_convert (type,
14258 const_binop (LSHIFT_EXPR,
14261 && !TREE_OVERFLOW (t1))
14262 return multiple_of_p (type, t1, bottom);
14267 /* Can't handle conversions from non-integral or wider integral type. */
14268 if ((TREE_CODE (TREE_TYPE (TREE_OPERAND (top, 0))) != INTEGER_TYPE)
14269 || (TYPE_PRECISION (type)
14270 < TYPE_PRECISION (TREE_TYPE (TREE_OPERAND (top, 0)))))
14273 /* .. fall through ... */
14276 return multiple_of_p (type, TREE_OPERAND (top, 0), bottom);
14279 if (TREE_CODE (bottom) != INTEGER_CST
14280 || integer_zerop (bottom)
14281 || (TYPE_UNSIGNED (type)
14282 && (tree_int_cst_sgn (top) < 0
14283 || tree_int_cst_sgn (bottom) < 0)))
14285 return integer_zerop (int_const_binop (TRUNC_MOD_EXPR,
14293 /* Return true if CODE or TYPE is known to be non-negative. */
14296 tree_simple_nonnegative_warnv_p (enum tree_code code, tree type)
14298 if ((TYPE_PRECISION (type) != 1 || TYPE_UNSIGNED (type))
14299 && truth_value_p (code))
14300 /* Truth values evaluate to 0 or 1, which is nonnegative unless we
14301 have a signed:1 type (where the value is -1 and 0). */
14306 /* Return true if (CODE OP0) is known to be non-negative. If the return
14307 value is based on the assumption that signed overflow is undefined,
14308 set *STRICT_OVERFLOW_P to true; otherwise, don't change
14309 *STRICT_OVERFLOW_P. */
14312 tree_unary_nonnegative_warnv_p (enum tree_code code, tree type, tree op0,
14313 bool *strict_overflow_p)
14315 if (TYPE_UNSIGNED (type))
14321 /* We can't return 1 if flag_wrapv is set because
14322 ABS_EXPR<INT_MIN> = INT_MIN. */
14323 if (!INTEGRAL_TYPE_P (type))
14325 if (TYPE_OVERFLOW_UNDEFINED (type))
14327 *strict_overflow_p = true;
14332 case NON_LVALUE_EXPR:
14334 case FIX_TRUNC_EXPR:
14335 return tree_expr_nonnegative_warnv_p (op0,
14336 strict_overflow_p);
14340 tree inner_type = TREE_TYPE (op0);
14341 tree outer_type = type;
14343 if (TREE_CODE (outer_type) == REAL_TYPE)
14345 if (TREE_CODE (inner_type) == REAL_TYPE)
14346 return tree_expr_nonnegative_warnv_p (op0,
14347 strict_overflow_p);
14348 if (TREE_CODE (inner_type) == INTEGER_TYPE)
14350 if (TYPE_UNSIGNED (inner_type))
14352 return tree_expr_nonnegative_warnv_p (op0,
14353 strict_overflow_p);
14356 else if (TREE_CODE (outer_type) == INTEGER_TYPE)
14358 if (TREE_CODE (inner_type) == REAL_TYPE)
14359 return tree_expr_nonnegative_warnv_p (op0,
14360 strict_overflow_p);
14361 if (TREE_CODE (inner_type) == INTEGER_TYPE)
14362 return TYPE_PRECISION (inner_type) < TYPE_PRECISION (outer_type)
14363 && TYPE_UNSIGNED (inner_type);
14369 return tree_simple_nonnegative_warnv_p (code, type);
14372 /* We don't know sign of `t', so be conservative and return false. */
14376 /* Return true if (CODE OP0 OP1) is known to be non-negative. If the return
14377 value is based on the assumption that signed overflow is undefined,
14378 set *STRICT_OVERFLOW_P to true; otherwise, don't change
14379 *STRICT_OVERFLOW_P. */
14382 tree_binary_nonnegative_warnv_p (enum tree_code code, tree type, tree op0,
14383 tree op1, bool *strict_overflow_p)
14385 if (TYPE_UNSIGNED (type))
14390 case POINTER_PLUS_EXPR:
14392 if (FLOAT_TYPE_P (type))
14393 return (tree_expr_nonnegative_warnv_p (op0,
14395 && tree_expr_nonnegative_warnv_p (op1,
14396 strict_overflow_p));
14398 /* zero_extend(x) + zero_extend(y) is non-negative if x and y are
14399 both unsigned and at least 2 bits shorter than the result. */
14400 if (TREE_CODE (type) == INTEGER_TYPE
14401 && TREE_CODE (op0) == NOP_EXPR
14402 && TREE_CODE (op1) == NOP_EXPR)
14404 tree inner1 = TREE_TYPE (TREE_OPERAND (op0, 0));
14405 tree inner2 = TREE_TYPE (TREE_OPERAND (op1, 0));
14406 if (TREE_CODE (inner1) == INTEGER_TYPE && TYPE_UNSIGNED (inner1)
14407 && TREE_CODE (inner2) == INTEGER_TYPE && TYPE_UNSIGNED (inner2))
14409 unsigned int prec = MAX (TYPE_PRECISION (inner1),
14410 TYPE_PRECISION (inner2)) + 1;
14411 return prec < TYPE_PRECISION (type);
14417 if (FLOAT_TYPE_P (type))
14419 /* x * x for floating point x is always non-negative. */
14420 if (operand_equal_p (op0, op1, 0))
14422 return (tree_expr_nonnegative_warnv_p (op0,
14424 && tree_expr_nonnegative_warnv_p (op1,
14425 strict_overflow_p));
14428 /* zero_extend(x) * zero_extend(y) is non-negative if x and y are
14429 both unsigned and their total bits is shorter than the result. */
14430 if (TREE_CODE (type) == INTEGER_TYPE
14431 && (TREE_CODE (op0) == NOP_EXPR || TREE_CODE (op0) == INTEGER_CST)
14432 && (TREE_CODE (op1) == NOP_EXPR || TREE_CODE (op1) == INTEGER_CST))
14434 tree inner0 = (TREE_CODE (op0) == NOP_EXPR)
14435 ? TREE_TYPE (TREE_OPERAND (op0, 0))
14437 tree inner1 = (TREE_CODE (op1) == NOP_EXPR)
14438 ? TREE_TYPE (TREE_OPERAND (op1, 0))
14441 bool unsigned0 = TYPE_UNSIGNED (inner0);
14442 bool unsigned1 = TYPE_UNSIGNED (inner1);
14444 if (TREE_CODE (op0) == INTEGER_CST)
14445 unsigned0 = unsigned0 || tree_int_cst_sgn (op0) >= 0;
14447 if (TREE_CODE (op1) == INTEGER_CST)
14448 unsigned1 = unsigned1 || tree_int_cst_sgn (op1) >= 0;
14450 if (TREE_CODE (inner0) == INTEGER_TYPE && unsigned0
14451 && TREE_CODE (inner1) == INTEGER_TYPE && unsigned1)
14453 unsigned int precision0 = (TREE_CODE (op0) == INTEGER_CST)
14454 ? tree_int_cst_min_precision (op0, /*unsignedp=*/true)
14455 : TYPE_PRECISION (inner0);
14457 unsigned int precision1 = (TREE_CODE (op1) == INTEGER_CST)
14458 ? tree_int_cst_min_precision (op1, /*unsignedp=*/true)
14459 : TYPE_PRECISION (inner1);
14461 return precision0 + precision1 < TYPE_PRECISION (type);
14468 return (tree_expr_nonnegative_warnv_p (op0,
14470 || tree_expr_nonnegative_warnv_p (op1,
14471 strict_overflow_p));
14477 case TRUNC_DIV_EXPR:
14478 case CEIL_DIV_EXPR:
14479 case FLOOR_DIV_EXPR:
14480 case ROUND_DIV_EXPR:
14481 return (tree_expr_nonnegative_warnv_p (op0,
14483 && tree_expr_nonnegative_warnv_p (op1,
14484 strict_overflow_p));
14486 case TRUNC_MOD_EXPR:
14487 case CEIL_MOD_EXPR:
14488 case FLOOR_MOD_EXPR:
14489 case ROUND_MOD_EXPR:
14490 return tree_expr_nonnegative_warnv_p (op0,
14491 strict_overflow_p);
14493 return tree_simple_nonnegative_warnv_p (code, type);
14496 /* We don't know sign of `t', so be conservative and return false. */
14500 /* Return true if T is known to be non-negative. If the return
14501 value is based on the assumption that signed overflow is undefined,
14502 set *STRICT_OVERFLOW_P to true; otherwise, don't change
14503 *STRICT_OVERFLOW_P. */
14506 tree_single_nonnegative_warnv_p (tree t, bool *strict_overflow_p)
14508 if (TYPE_UNSIGNED (TREE_TYPE (t)))
14511 switch (TREE_CODE (t))
14514 return tree_int_cst_sgn (t) >= 0;
14517 return ! REAL_VALUE_NEGATIVE (TREE_REAL_CST (t));
14520 return ! FIXED_VALUE_NEGATIVE (TREE_FIXED_CST (t));
14523 return (tree_expr_nonnegative_warnv_p (TREE_OPERAND (t, 1),
14525 && tree_expr_nonnegative_warnv_p (TREE_OPERAND (t, 2),
14526 strict_overflow_p));
14528 return tree_simple_nonnegative_warnv_p (TREE_CODE (t),
14531 /* We don't know sign of `t', so be conservative and return false. */
14535 /* Return true if T is known to be non-negative. If the return
14536 value is based on the assumption that signed overflow is undefined,
14537 set *STRICT_OVERFLOW_P to true; otherwise, don't change
14538 *STRICT_OVERFLOW_P. */
14541 tree_call_nonnegative_warnv_p (tree type, tree fndecl,
14542 tree arg0, tree arg1, bool *strict_overflow_p)
14544 if (fndecl && DECL_BUILT_IN_CLASS (fndecl) == BUILT_IN_NORMAL)
14545 switch (DECL_FUNCTION_CODE (fndecl))
14547 CASE_FLT_FN (BUILT_IN_ACOS):
14548 CASE_FLT_FN (BUILT_IN_ACOSH):
14549 CASE_FLT_FN (BUILT_IN_CABS):
14550 CASE_FLT_FN (BUILT_IN_COSH):
14551 CASE_FLT_FN (BUILT_IN_ERFC):
14552 CASE_FLT_FN (BUILT_IN_EXP):
14553 CASE_FLT_FN (BUILT_IN_EXP10):
14554 CASE_FLT_FN (BUILT_IN_EXP2):
14555 CASE_FLT_FN (BUILT_IN_FABS):
14556 CASE_FLT_FN (BUILT_IN_FDIM):
14557 CASE_FLT_FN (BUILT_IN_HYPOT):
14558 CASE_FLT_FN (BUILT_IN_POW10):
14559 CASE_INT_FN (BUILT_IN_FFS):
14560 CASE_INT_FN (BUILT_IN_PARITY):
14561 CASE_INT_FN (BUILT_IN_POPCOUNT):
14562 case BUILT_IN_BSWAP32:
14563 case BUILT_IN_BSWAP64:
14567 CASE_FLT_FN (BUILT_IN_SQRT):
14568 /* sqrt(-0.0) is -0.0. */
14569 if (!HONOR_SIGNED_ZEROS (TYPE_MODE (type)))
14571 return tree_expr_nonnegative_warnv_p (arg0,
14572 strict_overflow_p);
14574 CASE_FLT_FN (BUILT_IN_ASINH):
14575 CASE_FLT_FN (BUILT_IN_ATAN):
14576 CASE_FLT_FN (BUILT_IN_ATANH):
14577 CASE_FLT_FN (BUILT_IN_CBRT):
14578 CASE_FLT_FN (BUILT_IN_CEIL):
14579 CASE_FLT_FN (BUILT_IN_ERF):
14580 CASE_FLT_FN (BUILT_IN_EXPM1):
14581 CASE_FLT_FN (BUILT_IN_FLOOR):
14582 CASE_FLT_FN (BUILT_IN_FMOD):
14583 CASE_FLT_FN (BUILT_IN_FREXP):
14584 CASE_FLT_FN (BUILT_IN_LCEIL):
14585 CASE_FLT_FN (BUILT_IN_LDEXP):
14586 CASE_FLT_FN (BUILT_IN_LFLOOR):
14587 CASE_FLT_FN (BUILT_IN_LLCEIL):
14588 CASE_FLT_FN (BUILT_IN_LLFLOOR):
14589 CASE_FLT_FN (BUILT_IN_LLRINT):
14590 CASE_FLT_FN (BUILT_IN_LLROUND):
14591 CASE_FLT_FN (BUILT_IN_LRINT):
14592 CASE_FLT_FN (BUILT_IN_LROUND):
14593 CASE_FLT_FN (BUILT_IN_MODF):
14594 CASE_FLT_FN (BUILT_IN_NEARBYINT):
14595 CASE_FLT_FN (BUILT_IN_RINT):
14596 CASE_FLT_FN (BUILT_IN_ROUND):
14597 CASE_FLT_FN (BUILT_IN_SCALB):
14598 CASE_FLT_FN (BUILT_IN_SCALBLN):
14599 CASE_FLT_FN (BUILT_IN_SCALBN):
14600 CASE_FLT_FN (BUILT_IN_SIGNBIT):
14601 CASE_FLT_FN (BUILT_IN_SIGNIFICAND):
14602 CASE_FLT_FN (BUILT_IN_SINH):
14603 CASE_FLT_FN (BUILT_IN_TANH):
14604 CASE_FLT_FN (BUILT_IN_TRUNC):
14605 /* True if the 1st argument is nonnegative. */
14606 return tree_expr_nonnegative_warnv_p (arg0,
14607 strict_overflow_p);
14609 CASE_FLT_FN (BUILT_IN_FMAX):
14610 /* True if the 1st OR 2nd arguments are nonnegative. */
14611 return (tree_expr_nonnegative_warnv_p (arg0,
14613 || (tree_expr_nonnegative_warnv_p (arg1,
14614 strict_overflow_p)));
14616 CASE_FLT_FN (BUILT_IN_FMIN):
14617 /* True if the 1st AND 2nd arguments are nonnegative. */
14618 return (tree_expr_nonnegative_warnv_p (arg0,
14620 && (tree_expr_nonnegative_warnv_p (arg1,
14621 strict_overflow_p)));
14623 CASE_FLT_FN (BUILT_IN_COPYSIGN):
14624 /* True if the 2nd argument is nonnegative. */
14625 return tree_expr_nonnegative_warnv_p (arg1,
14626 strict_overflow_p);
14628 CASE_FLT_FN (BUILT_IN_POWI):
14629 /* True if the 1st argument is nonnegative or the second
14630 argument is an even integer. */
14631 if (TREE_CODE (arg1) == INTEGER_CST
14632 && (TREE_INT_CST_LOW (arg1) & 1) == 0)
14634 return tree_expr_nonnegative_warnv_p (arg0,
14635 strict_overflow_p);
14637 CASE_FLT_FN (BUILT_IN_POW):
14638 /* True if the 1st argument is nonnegative or the second
14639 argument is an even integer valued real. */
14640 if (TREE_CODE (arg1) == REAL_CST)
14645 c = TREE_REAL_CST (arg1);
14646 n = real_to_integer (&c);
14649 REAL_VALUE_TYPE cint;
14650 real_from_integer (&cint, VOIDmode, n,
14651 n < 0 ? -1 : 0, 0);
14652 if (real_identical (&c, &cint))
14656 return tree_expr_nonnegative_warnv_p (arg0,
14657 strict_overflow_p);
14662 return tree_simple_nonnegative_warnv_p (CALL_EXPR,
14666 /* Return true if T is known to be non-negative. If the return
14667 value is based on the assumption that signed overflow is undefined,
14668 set *STRICT_OVERFLOW_P to true; otherwise, don't change
14669 *STRICT_OVERFLOW_P. */
14672 tree_invalid_nonnegative_warnv_p (tree t, bool *strict_overflow_p)
14674 enum tree_code code = TREE_CODE (t);
14675 if (TYPE_UNSIGNED (TREE_TYPE (t)))
14682 tree temp = TARGET_EXPR_SLOT (t);
14683 t = TARGET_EXPR_INITIAL (t);
14685 /* If the initializer is non-void, then it's a normal expression
14686 that will be assigned to the slot. */
14687 if (!VOID_TYPE_P (t))
14688 return tree_expr_nonnegative_warnv_p (t, strict_overflow_p);
14690 /* Otherwise, the initializer sets the slot in some way. One common
14691 way is an assignment statement at the end of the initializer. */
14694 if (TREE_CODE (t) == BIND_EXPR)
14695 t = expr_last (BIND_EXPR_BODY (t));
14696 else if (TREE_CODE (t) == TRY_FINALLY_EXPR
14697 || TREE_CODE (t) == TRY_CATCH_EXPR)
14698 t = expr_last (TREE_OPERAND (t, 0));
14699 else if (TREE_CODE (t) == STATEMENT_LIST)
14704 if (TREE_CODE (t) == MODIFY_EXPR
14705 && TREE_OPERAND (t, 0) == temp)
14706 return tree_expr_nonnegative_warnv_p (TREE_OPERAND (t, 1),
14707 strict_overflow_p);
14714 tree arg0 = call_expr_nargs (t) > 0 ? CALL_EXPR_ARG (t, 0) : NULL_TREE;
14715 tree arg1 = call_expr_nargs (t) > 1 ? CALL_EXPR_ARG (t, 1) : NULL_TREE;
14717 return tree_call_nonnegative_warnv_p (TREE_TYPE (t),
14718 get_callee_fndecl (t),
14721 strict_overflow_p);
14723 case COMPOUND_EXPR:
14725 return tree_expr_nonnegative_warnv_p (TREE_OPERAND (t, 1),
14726 strict_overflow_p);
14728 return tree_expr_nonnegative_warnv_p (expr_last (TREE_OPERAND (t, 1)),
14729 strict_overflow_p);
14731 return tree_expr_nonnegative_warnv_p (TREE_OPERAND (t, 0),
14732 strict_overflow_p);
14735 return tree_simple_nonnegative_warnv_p (TREE_CODE (t),
14739 /* We don't know sign of `t', so be conservative and return false. */
14743 /* Return true if T is known to be non-negative. If the return
14744 value is based on the assumption that signed overflow is undefined,
14745 set *STRICT_OVERFLOW_P to true; otherwise, don't change
14746 *STRICT_OVERFLOW_P. */
14749 tree_expr_nonnegative_warnv_p (tree t, bool *strict_overflow_p)
14751 enum tree_code code;
14752 if (t == error_mark_node)
14755 code = TREE_CODE (t);
14756 switch (TREE_CODE_CLASS (code))
14759 case tcc_comparison:
14760 return tree_binary_nonnegative_warnv_p (TREE_CODE (t),
14762 TREE_OPERAND (t, 0),
14763 TREE_OPERAND (t, 1),
14764 strict_overflow_p);
14767 return tree_unary_nonnegative_warnv_p (TREE_CODE (t),
14769 TREE_OPERAND (t, 0),
14770 strict_overflow_p);
14773 case tcc_declaration:
14774 case tcc_reference:
14775 return tree_single_nonnegative_warnv_p (t, strict_overflow_p);
14783 case TRUTH_AND_EXPR:
14784 case TRUTH_OR_EXPR:
14785 case TRUTH_XOR_EXPR:
14786 return tree_binary_nonnegative_warnv_p (TREE_CODE (t),
14788 TREE_OPERAND (t, 0),
14789 TREE_OPERAND (t, 1),
14790 strict_overflow_p);
14791 case TRUTH_NOT_EXPR:
14792 return tree_unary_nonnegative_warnv_p (TREE_CODE (t),
14794 TREE_OPERAND (t, 0),
14795 strict_overflow_p);
14802 case WITH_SIZE_EXPR:
14806 return tree_single_nonnegative_warnv_p (t, strict_overflow_p);
14809 return tree_invalid_nonnegative_warnv_p (t, strict_overflow_p);
14813 /* Return true if `t' is known to be non-negative. Handle warnings
14814 about undefined signed overflow. */
14817 tree_expr_nonnegative_p (tree t)
14819 bool ret, strict_overflow_p;
14821 strict_overflow_p = false;
14822 ret = tree_expr_nonnegative_warnv_p (t, &strict_overflow_p);
14823 if (strict_overflow_p)
14824 fold_overflow_warning (("assuming signed overflow does not occur when "
14825 "determining that expression is always "
14827 WARN_STRICT_OVERFLOW_MISC);
14832 /* Return true when (CODE OP0) is an address and is known to be nonzero.
14833 For floating point we further ensure that T is not denormal.
14834 Similar logic is present in nonzero_address in rtlanal.h.
14836 If the return value is based on the assumption that signed overflow
14837 is undefined, set *STRICT_OVERFLOW_P to true; otherwise, don't
14838 change *STRICT_OVERFLOW_P. */
14841 tree_unary_nonzero_warnv_p (enum tree_code code, tree type, tree op0,
14842 bool *strict_overflow_p)
14847 return tree_expr_nonzero_warnv_p (op0,
14848 strict_overflow_p);
14852 tree inner_type = TREE_TYPE (op0);
14853 tree outer_type = type;
14855 return (TYPE_PRECISION (outer_type) >= TYPE_PRECISION (inner_type)
14856 && tree_expr_nonzero_warnv_p (op0,
14857 strict_overflow_p));
14861 case NON_LVALUE_EXPR:
14862 return tree_expr_nonzero_warnv_p (op0,
14863 strict_overflow_p);
14872 /* Return true when (CODE OP0 OP1) is an address and is known to be nonzero.
14873 For floating point we further ensure that T is not denormal.
14874 Similar logic is present in nonzero_address in rtlanal.h.
14876 If the return value is based on the assumption that signed overflow
14877 is undefined, set *STRICT_OVERFLOW_P to true; otherwise, don't
14878 change *STRICT_OVERFLOW_P. */
14881 tree_binary_nonzero_warnv_p (enum tree_code code,
14884 tree op1, bool *strict_overflow_p)
14886 bool sub_strict_overflow_p;
14889 case POINTER_PLUS_EXPR:
14891 if (TYPE_OVERFLOW_UNDEFINED (type))
14893 /* With the presence of negative values it is hard
14894 to say something. */
14895 sub_strict_overflow_p = false;
14896 if (!tree_expr_nonnegative_warnv_p (op0,
14897 &sub_strict_overflow_p)
14898 || !tree_expr_nonnegative_warnv_p (op1,
14899 &sub_strict_overflow_p))
14901 /* One of operands must be positive and the other non-negative. */
14902 /* We don't set *STRICT_OVERFLOW_P here: even if this value
14903 overflows, on a twos-complement machine the sum of two
14904 nonnegative numbers can never be zero. */
14905 return (tree_expr_nonzero_warnv_p (op0,
14907 || tree_expr_nonzero_warnv_p (op1,
14908 strict_overflow_p));
14913 if (TYPE_OVERFLOW_UNDEFINED (type))
14915 if (tree_expr_nonzero_warnv_p (op0,
14917 && tree_expr_nonzero_warnv_p (op1,
14918 strict_overflow_p))
14920 *strict_overflow_p = true;
14927 sub_strict_overflow_p = false;
14928 if (tree_expr_nonzero_warnv_p (op0,
14929 &sub_strict_overflow_p)
14930 && tree_expr_nonzero_warnv_p (op1,
14931 &sub_strict_overflow_p))
14933 if (sub_strict_overflow_p)
14934 *strict_overflow_p = true;
14939 sub_strict_overflow_p = false;
14940 if (tree_expr_nonzero_warnv_p (op0,
14941 &sub_strict_overflow_p))
14943 if (sub_strict_overflow_p)
14944 *strict_overflow_p = true;
14946 /* When both operands are nonzero, then MAX must be too. */
14947 if (tree_expr_nonzero_warnv_p (op1,
14948 strict_overflow_p))
14951 /* MAX where operand 0 is positive is positive. */
14952 return tree_expr_nonnegative_warnv_p (op0,
14953 strict_overflow_p);
14955 /* MAX where operand 1 is positive is positive. */
14956 else if (tree_expr_nonzero_warnv_p (op1,
14957 &sub_strict_overflow_p)
14958 && tree_expr_nonnegative_warnv_p (op1,
14959 &sub_strict_overflow_p))
14961 if (sub_strict_overflow_p)
14962 *strict_overflow_p = true;
14968 return (tree_expr_nonzero_warnv_p (op1,
14970 || tree_expr_nonzero_warnv_p (op0,
14971 strict_overflow_p));
14980 /* Return true when T is an address and is known to be nonzero.
14981 For floating point we further ensure that T is not denormal.
14982 Similar logic is present in nonzero_address in rtlanal.h.
14984 If the return value is based on the assumption that signed overflow
14985 is undefined, set *STRICT_OVERFLOW_P to true; otherwise, don't
14986 change *STRICT_OVERFLOW_P. */
14989 tree_single_nonzero_warnv_p (tree t, bool *strict_overflow_p)
14991 bool sub_strict_overflow_p;
14992 switch (TREE_CODE (t))
14995 return !integer_zerop (t);
14999 tree base = get_base_address (TREE_OPERAND (t, 0));
15004 /* Weak declarations may link to NULL. */
15005 if (VAR_OR_FUNCTION_DECL_P (base))
15006 return !DECL_WEAK (base);
15008 /* Constants are never weak. */
15009 if (CONSTANT_CLASS_P (base))
15016 sub_strict_overflow_p = false;
15017 if (tree_expr_nonzero_warnv_p (TREE_OPERAND (t, 1),
15018 &sub_strict_overflow_p)
15019 && tree_expr_nonzero_warnv_p (TREE_OPERAND (t, 2),
15020 &sub_strict_overflow_p))
15022 if (sub_strict_overflow_p)
15023 *strict_overflow_p = true;
15034 /* Return true when T is an address and is known to be nonzero.
15035 For floating point we further ensure that T is not denormal.
15036 Similar logic is present in nonzero_address in rtlanal.h.
15038 If the return value is based on the assumption that signed overflow
15039 is undefined, set *STRICT_OVERFLOW_P to true; otherwise, don't
15040 change *STRICT_OVERFLOW_P. */
15043 tree_expr_nonzero_warnv_p (tree t, bool *strict_overflow_p)
15045 tree type = TREE_TYPE (t);
15046 enum tree_code code;
15048 /* Doing something useful for floating point would need more work. */
15049 if (!INTEGRAL_TYPE_P (type) && !POINTER_TYPE_P (type))
15052 code = TREE_CODE (t);
15053 switch (TREE_CODE_CLASS (code))
15056 return tree_unary_nonzero_warnv_p (code, type, TREE_OPERAND (t, 0),
15057 strict_overflow_p);
15059 case tcc_comparison:
15060 return tree_binary_nonzero_warnv_p (code, type,
15061 TREE_OPERAND (t, 0),
15062 TREE_OPERAND (t, 1),
15063 strict_overflow_p);
15065 case tcc_declaration:
15066 case tcc_reference:
15067 return tree_single_nonzero_warnv_p (t, strict_overflow_p);
15075 case TRUTH_NOT_EXPR:
15076 return tree_unary_nonzero_warnv_p (code, type, TREE_OPERAND (t, 0),
15077 strict_overflow_p);
15079 case TRUTH_AND_EXPR:
15080 case TRUTH_OR_EXPR:
15081 case TRUTH_XOR_EXPR:
15082 return tree_binary_nonzero_warnv_p (code, type,
15083 TREE_OPERAND (t, 0),
15084 TREE_OPERAND (t, 1),
15085 strict_overflow_p);
15092 case WITH_SIZE_EXPR:
15096 return tree_single_nonzero_warnv_p (t, strict_overflow_p);
15098 case COMPOUND_EXPR:
15101 return tree_expr_nonzero_warnv_p (TREE_OPERAND (t, 1),
15102 strict_overflow_p);
15105 return tree_expr_nonzero_warnv_p (TREE_OPERAND (t, 0),
15106 strict_overflow_p);
15109 return alloca_call_p (t);
15117 /* Return true when T is an address and is known to be nonzero.
15118 Handle warnings about undefined signed overflow. */
15121 tree_expr_nonzero_p (tree t)
15123 bool ret, strict_overflow_p;
15125 strict_overflow_p = false;
15126 ret = tree_expr_nonzero_warnv_p (t, &strict_overflow_p);
15127 if (strict_overflow_p)
15128 fold_overflow_warning (("assuming signed overflow does not occur when "
15129 "determining that expression is always "
15131 WARN_STRICT_OVERFLOW_MISC);
15135 /* Given the components of a binary expression CODE, TYPE, OP0 and OP1,
15136 attempt to fold the expression to a constant without modifying TYPE,
15139 If the expression could be simplified to a constant, then return
15140 the constant. If the expression would not be simplified to a
15141 constant, then return NULL_TREE. */
15144 fold_binary_to_constant (enum tree_code code, tree type, tree op0, tree op1)
15146 tree tem = fold_binary (code, type, op0, op1);
15147 return (tem && TREE_CONSTANT (tem)) ? tem : NULL_TREE;
15150 /* Given the components of a unary expression CODE, TYPE and OP0,
15151 attempt to fold the expression to a constant without modifying
15154 If the expression could be simplified to a constant, then return
15155 the constant. If the expression would not be simplified to a
15156 constant, then return NULL_TREE. */
15159 fold_unary_to_constant (enum tree_code code, tree type, tree op0)
15161 tree tem = fold_unary (code, type, op0);
15162 return (tem && TREE_CONSTANT (tem)) ? tem : NULL_TREE;
15165 /* If EXP represents referencing an element in a constant string
15166 (either via pointer arithmetic or array indexing), return the
15167 tree representing the value accessed, otherwise return NULL. */
15170 fold_read_from_constant_string (tree exp)
15172 if ((TREE_CODE (exp) == INDIRECT_REF
15173 || TREE_CODE (exp) == ARRAY_REF)
15174 && TREE_CODE (TREE_TYPE (exp)) == INTEGER_TYPE)
15176 tree exp1 = TREE_OPERAND (exp, 0);
15180 if (TREE_CODE (exp) == INDIRECT_REF)
15181 string = string_constant (exp1, &index);
15184 tree low_bound = array_ref_low_bound (exp);
15185 index = fold_convert (sizetype, TREE_OPERAND (exp, 1));
15187 /* Optimize the special-case of a zero lower bound.
15189 We convert the low_bound to sizetype to avoid some problems
15190 with constant folding. (E.g. suppose the lower bound is 1,
15191 and its mode is QI. Without the conversion,l (ARRAY
15192 +(INDEX-(unsigned char)1)) becomes ((ARRAY+(-(unsigned char)1))
15193 +INDEX), which becomes (ARRAY+255+INDEX). Oops!) */
15194 if (! integer_zerop (low_bound))
15195 index = size_diffop (index, fold_convert (sizetype, low_bound));
15201 && TYPE_MODE (TREE_TYPE (exp)) == TYPE_MODE (TREE_TYPE (TREE_TYPE (string)))
15202 && TREE_CODE (string) == STRING_CST
15203 && TREE_CODE (index) == INTEGER_CST
15204 && compare_tree_int (index, TREE_STRING_LENGTH (string)) < 0
15205 && (GET_MODE_CLASS (TYPE_MODE (TREE_TYPE (TREE_TYPE (string))))
15207 && (GET_MODE_SIZE (TYPE_MODE (TREE_TYPE (TREE_TYPE (string)))) == 1))
15208 return build_int_cst_type (TREE_TYPE (exp),
15209 (TREE_STRING_POINTER (string)
15210 [TREE_INT_CST_LOW (index)]));
15215 /* Return the tree for neg (ARG0) when ARG0 is known to be either
15216 an integer constant, real, or fixed-point constant.
15218 TYPE is the type of the result. */
15221 fold_negate_const (tree arg0, tree type)
15223 tree t = NULL_TREE;
15225 switch (TREE_CODE (arg0))
15229 unsigned HOST_WIDE_INT low;
15230 HOST_WIDE_INT high;
15231 int overflow = neg_double (TREE_INT_CST_LOW (arg0),
15232 TREE_INT_CST_HIGH (arg0),
15234 t = force_fit_type_double (type, low, high, 1,
15235 (overflow | TREE_OVERFLOW (arg0))
15236 && !TYPE_UNSIGNED (type));
15241 t = build_real (type, REAL_VALUE_NEGATE (TREE_REAL_CST (arg0)));
15246 FIXED_VALUE_TYPE f;
15247 bool overflow_p = fixed_arithmetic (&f, NEGATE_EXPR,
15248 &(TREE_FIXED_CST (arg0)), NULL,
15249 TYPE_SATURATING (type));
15250 t = build_fixed (type, f);
15251 /* Propagate overflow flags. */
15252 if (overflow_p | TREE_OVERFLOW (arg0))
15254 TREE_OVERFLOW (t) = 1;
15255 TREE_CONSTANT_OVERFLOW (t) = 1;
15257 else if (TREE_CONSTANT_OVERFLOW (arg0))
15258 TREE_CONSTANT_OVERFLOW (t) = 1;
15263 gcc_unreachable ();
15269 /* Return the tree for abs (ARG0) when ARG0 is known to be either
15270 an integer constant or real constant.
15272 TYPE is the type of the result. */
15275 fold_abs_const (tree arg0, tree type)
15277 tree t = NULL_TREE;
15279 switch (TREE_CODE (arg0))
15282 /* If the value is unsigned, then the absolute value is
15283 the same as the ordinary value. */
15284 if (TYPE_UNSIGNED (type))
15286 /* Similarly, if the value is non-negative. */
15287 else if (INT_CST_LT (integer_minus_one_node, arg0))
15289 /* If the value is negative, then the absolute value is
15293 unsigned HOST_WIDE_INT low;
15294 HOST_WIDE_INT high;
15295 int overflow = neg_double (TREE_INT_CST_LOW (arg0),
15296 TREE_INT_CST_HIGH (arg0),
15298 t = force_fit_type_double (type, low, high, -1,
15299 overflow | TREE_OVERFLOW (arg0));
15304 if (REAL_VALUE_NEGATIVE (TREE_REAL_CST (arg0)))
15305 t = build_real (type, REAL_VALUE_NEGATE (TREE_REAL_CST (arg0)));
15311 gcc_unreachable ();
15317 /* Return the tree for not (ARG0) when ARG0 is known to be an integer
15318 constant. TYPE is the type of the result. */
15321 fold_not_const (tree arg0, tree type)
15323 tree t = NULL_TREE;
15325 gcc_assert (TREE_CODE (arg0) == INTEGER_CST);
15327 t = force_fit_type_double (type, ~TREE_INT_CST_LOW (arg0),
15328 ~TREE_INT_CST_HIGH (arg0), 0,
15329 TREE_OVERFLOW (arg0));
15334 /* Given CODE, a relational operator, the target type, TYPE and two
15335 constant operands OP0 and OP1, return the result of the
15336 relational operation. If the result is not a compile time
15337 constant, then return NULL_TREE. */
15340 fold_relational_const (enum tree_code code, tree type, tree op0, tree op1)
15342 int result, invert;
15344 /* From here on, the only cases we handle are when the result is
15345 known to be a constant. */
15347 if (TREE_CODE (op0) == REAL_CST && TREE_CODE (op1) == REAL_CST)
15349 const REAL_VALUE_TYPE *c0 = TREE_REAL_CST_PTR (op0);
15350 const REAL_VALUE_TYPE *c1 = TREE_REAL_CST_PTR (op1);
15352 /* Handle the cases where either operand is a NaN. */
15353 if (real_isnan (c0) || real_isnan (c1))
15363 case UNORDERED_EXPR:
15377 if (flag_trapping_math)
15383 gcc_unreachable ();
15386 return constant_boolean_node (result, type);
15389 return constant_boolean_node (real_compare (code, c0, c1), type);
15392 if (TREE_CODE (op0) == FIXED_CST && TREE_CODE (op1) == FIXED_CST)
15394 const FIXED_VALUE_TYPE *c0 = TREE_FIXED_CST_PTR (op0);
15395 const FIXED_VALUE_TYPE *c1 = TREE_FIXED_CST_PTR (op1);
15396 return constant_boolean_node (fixed_compare (code, c0, c1), type);
15399 /* Handle equality/inequality of complex constants. */
15400 if (TREE_CODE (op0) == COMPLEX_CST && TREE_CODE (op1) == COMPLEX_CST)
15402 tree rcond = fold_relational_const (code, type,
15403 TREE_REALPART (op0),
15404 TREE_REALPART (op1));
15405 tree icond = fold_relational_const (code, type,
15406 TREE_IMAGPART (op0),
15407 TREE_IMAGPART (op1));
15408 if (code == EQ_EXPR)
15409 return fold_build2 (TRUTH_ANDIF_EXPR, type, rcond, icond);
15410 else if (code == NE_EXPR)
15411 return fold_build2 (TRUTH_ORIF_EXPR, type, rcond, icond);
15416 /* From here on we only handle LT, LE, GT, GE, EQ and NE.
15418 To compute GT, swap the arguments and do LT.
15419 To compute GE, do LT and invert the result.
15420 To compute LE, swap the arguments, do LT and invert the result.
15421 To compute NE, do EQ and invert the result.
15423 Therefore, the code below must handle only EQ and LT. */
15425 if (code == LE_EXPR || code == GT_EXPR)
15430 code = swap_tree_comparison (code);
15433 /* Note that it is safe to invert for real values here because we
15434 have already handled the one case that it matters. */
15437 if (code == NE_EXPR || code == GE_EXPR)
15440 code = invert_tree_comparison (code, false);
15443 /* Compute a result for LT or EQ if args permit;
15444 Otherwise return T. */
15445 if (TREE_CODE (op0) == INTEGER_CST && TREE_CODE (op1) == INTEGER_CST)
15447 if (code == EQ_EXPR)
15448 result = tree_int_cst_equal (op0, op1);
15449 else if (TYPE_UNSIGNED (TREE_TYPE (op0)))
15450 result = INT_CST_LT_UNSIGNED (op0, op1);
15452 result = INT_CST_LT (op0, op1);
15459 return constant_boolean_node (result, type);
15462 /* If necessary, return a CLEANUP_POINT_EXPR for EXPR with the
15463 indicated TYPE. If no CLEANUP_POINT_EXPR is necessary, return EXPR
15467 fold_build_cleanup_point_expr (tree type, tree expr)
15469 /* If the expression does not have side effects then we don't have to wrap
15470 it with a cleanup point expression. */
15471 if (!TREE_SIDE_EFFECTS (expr))
15474 /* If the expression is a return, check to see if the expression inside the
15475 return has no side effects or the right hand side of the modify expression
15476 inside the return. If either don't have side effects set we don't need to
15477 wrap the expression in a cleanup point expression. Note we don't check the
15478 left hand side of the modify because it should always be a return decl. */
15479 if (TREE_CODE (expr) == RETURN_EXPR)
15481 tree op = TREE_OPERAND (expr, 0);
15482 if (!op || !TREE_SIDE_EFFECTS (op))
15484 op = TREE_OPERAND (op, 1);
15485 if (!TREE_SIDE_EFFECTS (op))
15489 return build1 (CLEANUP_POINT_EXPR, type, expr);
15492 /* Given a pointer value OP0 and a type TYPE, return a simplified version
15493 of an indirection through OP0, or NULL_TREE if no simplification is
15497 fold_indirect_ref_1 (tree type, tree op0)
15503 subtype = TREE_TYPE (sub);
15504 if (!POINTER_TYPE_P (subtype))
15507 if (TREE_CODE (sub) == ADDR_EXPR)
15509 tree op = TREE_OPERAND (sub, 0);
15510 tree optype = TREE_TYPE (op);
15511 /* *&CONST_DECL -> to the value of the const decl. */
15512 if (TREE_CODE (op) == CONST_DECL)
15513 return DECL_INITIAL (op);
15514 /* *&p => p; make sure to handle *&"str"[cst] here. */
15515 if (type == optype)
15517 tree fop = fold_read_from_constant_string (op);
15523 /* *(foo *)&fooarray => fooarray[0] */
15524 else if (TREE_CODE (optype) == ARRAY_TYPE
15525 && type == TREE_TYPE (optype))
15527 tree type_domain = TYPE_DOMAIN (optype);
15528 tree min_val = size_zero_node;
15529 if (type_domain && TYPE_MIN_VALUE (type_domain))
15530 min_val = TYPE_MIN_VALUE (type_domain);
15531 return build4 (ARRAY_REF, type, op, min_val, NULL_TREE, NULL_TREE);
15533 /* *(foo *)&complexfoo => __real__ complexfoo */
15534 else if (TREE_CODE (optype) == COMPLEX_TYPE
15535 && type == TREE_TYPE (optype))
15536 return fold_build1 (REALPART_EXPR, type, op);
15537 /* *(foo *)&vectorfoo => BIT_FIELD_REF<vectorfoo,...> */
15538 else if (TREE_CODE (optype) == VECTOR_TYPE
15539 && type == TREE_TYPE (optype))
15541 tree part_width = TYPE_SIZE (type);
15542 tree index = bitsize_int (0);
15543 return fold_build3 (BIT_FIELD_REF, type, op, part_width, index);
15547 /* ((foo*)&vectorfoo)[1] => BIT_FIELD_REF<vectorfoo,...> */
15548 if (TREE_CODE (sub) == POINTER_PLUS_EXPR
15549 && TREE_CODE (TREE_OPERAND (sub, 1)) == INTEGER_CST)
15551 tree op00 = TREE_OPERAND (sub, 0);
15552 tree op01 = TREE_OPERAND (sub, 1);
15556 op00type = TREE_TYPE (op00);
15557 if (TREE_CODE (op00) == ADDR_EXPR
15558 && TREE_CODE (TREE_TYPE (op00type)) == VECTOR_TYPE
15559 && type == TREE_TYPE (TREE_TYPE (op00type)))
15561 HOST_WIDE_INT offset = tree_low_cst (op01, 0);
15562 tree part_width = TYPE_SIZE (type);
15563 unsigned HOST_WIDE_INT part_widthi = tree_low_cst (part_width, 0)/BITS_PER_UNIT;
15564 unsigned HOST_WIDE_INT indexi = offset * BITS_PER_UNIT;
15565 tree index = bitsize_int (indexi);
15567 if (offset/part_widthi <= TYPE_VECTOR_SUBPARTS (TREE_TYPE (op00type)))
15568 return fold_build3 (BIT_FIELD_REF, type, TREE_OPERAND (op00, 0),
15569 part_width, index);
15575 /* ((foo*)&complexfoo)[1] => __imag__ complexfoo */
15576 if (TREE_CODE (sub) == POINTER_PLUS_EXPR
15577 && TREE_CODE (TREE_OPERAND (sub, 1)) == INTEGER_CST)
15579 tree op00 = TREE_OPERAND (sub, 0);
15580 tree op01 = TREE_OPERAND (sub, 1);
15584 op00type = TREE_TYPE (op00);
15585 if (TREE_CODE (op00) == ADDR_EXPR
15586 && TREE_CODE (TREE_TYPE (op00type)) == COMPLEX_TYPE
15587 && type == TREE_TYPE (TREE_TYPE (op00type)))
15589 tree size = TYPE_SIZE_UNIT (type);
15590 if (tree_int_cst_equal (size, op01))
15591 return fold_build1 (IMAGPART_EXPR, type, TREE_OPERAND (op00, 0));
15595 /* *(foo *)fooarrptr => (*fooarrptr)[0] */
15596 if (TREE_CODE (TREE_TYPE (subtype)) == ARRAY_TYPE
15597 && type == TREE_TYPE (TREE_TYPE (subtype)))
15600 tree min_val = size_zero_node;
15601 sub = build_fold_indirect_ref (sub);
15602 type_domain = TYPE_DOMAIN (TREE_TYPE (sub));
15603 if (type_domain && TYPE_MIN_VALUE (type_domain))
15604 min_val = TYPE_MIN_VALUE (type_domain);
15605 return build4 (ARRAY_REF, type, sub, min_val, NULL_TREE, NULL_TREE);
15611 /* Builds an expression for an indirection through T, simplifying some
15615 build_fold_indirect_ref (tree t)
15617 tree type = TREE_TYPE (TREE_TYPE (t));
15618 tree sub = fold_indirect_ref_1 (type, t);
15623 return build1 (INDIRECT_REF, type, t);
15626 /* Given an INDIRECT_REF T, return either T or a simplified version. */
15629 fold_indirect_ref (tree t)
15631 tree sub = fold_indirect_ref_1 (TREE_TYPE (t), TREE_OPERAND (t, 0));
15639 /* Strip non-trapping, non-side-effecting tree nodes from an expression
15640 whose result is ignored. The type of the returned tree need not be
15641 the same as the original expression. */
15644 fold_ignored_result (tree t)
15646 if (!TREE_SIDE_EFFECTS (t))
15647 return integer_zero_node;
15650 switch (TREE_CODE_CLASS (TREE_CODE (t)))
15653 t = TREE_OPERAND (t, 0);
15657 case tcc_comparison:
15658 if (!TREE_SIDE_EFFECTS (TREE_OPERAND (t, 1)))
15659 t = TREE_OPERAND (t, 0);
15660 else if (!TREE_SIDE_EFFECTS (TREE_OPERAND (t, 0)))
15661 t = TREE_OPERAND (t, 1);
15666 case tcc_expression:
15667 switch (TREE_CODE (t))
15669 case COMPOUND_EXPR:
15670 if (TREE_SIDE_EFFECTS (TREE_OPERAND (t, 1)))
15672 t = TREE_OPERAND (t, 0);
15676 if (TREE_SIDE_EFFECTS (TREE_OPERAND (t, 1))
15677 || TREE_SIDE_EFFECTS (TREE_OPERAND (t, 2)))
15679 t = TREE_OPERAND (t, 0);
15692 /* Return the value of VALUE, rounded up to a multiple of DIVISOR.
15693 This can only be applied to objects of a sizetype. */
15696 round_up (tree value, int divisor)
15698 tree div = NULL_TREE;
15700 gcc_assert (divisor > 0);
15704 /* See if VALUE is already a multiple of DIVISOR. If so, we don't
15705 have to do anything. Only do this when we are not given a const,
15706 because in that case, this check is more expensive than just
15708 if (TREE_CODE (value) != INTEGER_CST)
15710 div = build_int_cst (TREE_TYPE (value), divisor);
15712 if (multiple_of_p (TREE_TYPE (value), value, div))
15716 /* If divisor is a power of two, simplify this to bit manipulation. */
15717 if (divisor == (divisor & -divisor))
15719 if (TREE_CODE (value) == INTEGER_CST)
15721 unsigned HOST_WIDE_INT low = TREE_INT_CST_LOW (value);
15722 unsigned HOST_WIDE_INT high;
15725 if ((low & (divisor - 1)) == 0)
15728 overflow_p = TREE_OVERFLOW (value);
15729 high = TREE_INT_CST_HIGH (value);
15730 low &= ~(divisor - 1);
15739 return force_fit_type_double (TREE_TYPE (value), low, high,
15746 t = build_int_cst (TREE_TYPE (value), divisor - 1);
15747 value = size_binop (PLUS_EXPR, value, t);
15748 t = build_int_cst (TREE_TYPE (value), -divisor);
15749 value = size_binop (BIT_AND_EXPR, value, t);
15755 div = build_int_cst (TREE_TYPE (value), divisor);
15756 value = size_binop (CEIL_DIV_EXPR, value, div);
15757 value = size_binop (MULT_EXPR, value, div);
15763 /* Likewise, but round down. */
15766 round_down (tree value, int divisor)
15768 tree div = NULL_TREE;
15770 gcc_assert (divisor > 0);
15774 /* See if VALUE is already a multiple of DIVISOR. If so, we don't
15775 have to do anything. Only do this when we are not given a const,
15776 because in that case, this check is more expensive than just
15778 if (TREE_CODE (value) != INTEGER_CST)
15780 div = build_int_cst (TREE_TYPE (value), divisor);
15782 if (multiple_of_p (TREE_TYPE (value), value, div))
15786 /* If divisor is a power of two, simplify this to bit manipulation. */
15787 if (divisor == (divisor & -divisor))
15791 t = build_int_cst (TREE_TYPE (value), -divisor);
15792 value = size_binop (BIT_AND_EXPR, value, t);
15797 div = build_int_cst (TREE_TYPE (value), divisor);
15798 value = size_binop (FLOOR_DIV_EXPR, value, div);
15799 value = size_binop (MULT_EXPR, value, div);
15805 /* Returns the pointer to the base of the object addressed by EXP and
15806 extracts the information about the offset of the access, storing it
15807 to PBITPOS and POFFSET. */
15810 split_address_to_core_and_offset (tree exp,
15811 HOST_WIDE_INT *pbitpos, tree *poffset)
15814 enum machine_mode mode;
15815 int unsignedp, volatilep;
15816 HOST_WIDE_INT bitsize;
15818 if (TREE_CODE (exp) == ADDR_EXPR)
15820 core = get_inner_reference (TREE_OPERAND (exp, 0), &bitsize, pbitpos,
15821 poffset, &mode, &unsignedp, &volatilep,
15823 core = fold_addr_expr (core);
15829 *poffset = NULL_TREE;
15835 /* Returns true if addresses of E1 and E2 differ by a constant, false
15836 otherwise. If they do, E1 - E2 is stored in *DIFF. */
15839 ptr_difference_const (tree e1, tree e2, HOST_WIDE_INT *diff)
15842 HOST_WIDE_INT bitpos1, bitpos2;
15843 tree toffset1, toffset2, tdiff, type;
15845 core1 = split_address_to_core_and_offset (e1, &bitpos1, &toffset1);
15846 core2 = split_address_to_core_and_offset (e2, &bitpos2, &toffset2);
15848 if (bitpos1 % BITS_PER_UNIT != 0
15849 || bitpos2 % BITS_PER_UNIT != 0
15850 || !operand_equal_p (core1, core2, 0))
15853 if (toffset1 && toffset2)
15855 type = TREE_TYPE (toffset1);
15856 if (type != TREE_TYPE (toffset2))
15857 toffset2 = fold_convert (type, toffset2);
15859 tdiff = fold_build2 (MINUS_EXPR, type, toffset1, toffset2);
15860 if (!cst_and_fits_in_hwi (tdiff))
15863 *diff = int_cst_value (tdiff);
15865 else if (toffset1 || toffset2)
15867 /* If only one of the offsets is non-constant, the difference cannot
15874 *diff += (bitpos1 - bitpos2) / BITS_PER_UNIT;
15878 /* Simplify the floating point expression EXP when the sign of the
15879 result is not significant. Return NULL_TREE if no simplification
15883 fold_strip_sign_ops (tree exp)
15887 switch (TREE_CODE (exp))
15891 arg0 = fold_strip_sign_ops (TREE_OPERAND (exp, 0));
15892 return arg0 ? arg0 : TREE_OPERAND (exp, 0);
15896 if (HONOR_SIGN_DEPENDENT_ROUNDING (TYPE_MODE (TREE_TYPE (exp))))
15898 arg0 = fold_strip_sign_ops (TREE_OPERAND (exp, 0));
15899 arg1 = fold_strip_sign_ops (TREE_OPERAND (exp, 1));
15900 if (arg0 != NULL_TREE || arg1 != NULL_TREE)
15901 return fold_build2 (TREE_CODE (exp), TREE_TYPE (exp),
15902 arg0 ? arg0 : TREE_OPERAND (exp, 0),
15903 arg1 ? arg1 : TREE_OPERAND (exp, 1));
15906 case COMPOUND_EXPR:
15907 arg0 = TREE_OPERAND (exp, 0);
15908 arg1 = fold_strip_sign_ops (TREE_OPERAND (exp, 1));
15910 return fold_build2 (COMPOUND_EXPR, TREE_TYPE (exp), arg0, arg1);
15914 arg0 = fold_strip_sign_ops (TREE_OPERAND (exp, 1));
15915 arg1 = fold_strip_sign_ops (TREE_OPERAND (exp, 2));
15917 return fold_build3 (COND_EXPR, TREE_TYPE (exp), TREE_OPERAND (exp, 0),
15918 arg0 ? arg0 : TREE_OPERAND (exp, 1),
15919 arg1 ? arg1 : TREE_OPERAND (exp, 2));
15924 const enum built_in_function fcode = builtin_mathfn_code (exp);
15927 CASE_FLT_FN (BUILT_IN_COPYSIGN):
15928 /* Strip copysign function call, return the 1st argument. */
15929 arg0 = CALL_EXPR_ARG (exp, 0);
15930 arg1 = CALL_EXPR_ARG (exp, 1);
15931 return omit_one_operand (TREE_TYPE (exp), arg0, arg1);
15934 /* Strip sign ops from the argument of "odd" math functions. */
15935 if (negate_mathfn_p (fcode))
15937 arg0 = fold_strip_sign_ops (CALL_EXPR_ARG (exp, 0));
15939 return build_call_expr (get_callee_fndecl (exp), 1, arg0);