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, 2009
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 int operand_equal_for_comparison_p (tree, tree, tree);
107 static int twoval_comparison_p (tree, tree *, tree *, int *);
108 static tree eval_subst (tree, tree, tree, tree, tree);
109 static tree pedantic_omit_one_operand (tree, tree, tree);
110 static tree distribute_bit_expr (enum tree_code, tree, tree, tree);
111 static tree make_bit_field_ref (tree, tree, HOST_WIDE_INT, HOST_WIDE_INT, int);
112 static tree optimize_bit_field_compare (enum tree_code, tree, tree, tree);
113 static tree decode_field_reference (tree, HOST_WIDE_INT *, HOST_WIDE_INT *,
114 enum machine_mode *, int *, int *,
116 static int all_ones_mask_p (const_tree, int);
117 static tree sign_bit_p (tree, const_tree);
118 static int simple_operand_p (const_tree);
119 static tree range_binop (enum tree_code, tree, tree, int, tree, int);
120 static tree range_predecessor (tree);
121 static tree range_successor (tree);
122 static tree make_range (tree, int *, tree *, tree *, bool *);
123 static tree build_range_check (tree, tree, int, tree, tree);
124 static int merge_ranges (int *, tree *, tree *, int, tree, tree, int, tree,
126 static tree fold_range_test (enum tree_code, tree, tree, tree);
127 static tree fold_cond_expr_with_comparison (tree, tree, tree, tree);
128 static tree unextend (tree, int, int, tree);
129 static tree fold_truthop (enum tree_code, tree, tree, tree);
130 static tree optimize_minmax_comparison (enum tree_code, tree, tree, tree);
131 static tree extract_muldiv (tree, tree, enum tree_code, tree, bool *);
132 static tree extract_muldiv_1 (tree, tree, enum tree_code, tree, bool *);
133 static tree fold_binary_op_with_conditional_arg (enum tree_code, tree,
136 static tree fold_mathfn_compare (enum built_in_function, enum tree_code,
138 static tree fold_inf_compare (enum tree_code, tree, tree, tree);
139 static tree fold_div_compare (enum tree_code, tree, tree, tree);
140 static bool reorder_operands_p (const_tree, const_tree);
141 static tree fold_negate_const (tree, tree);
142 static tree fold_not_const (tree, tree);
143 static tree fold_relational_const (enum tree_code, tree, tree, tree);
144 static tree fold_convert_const (enum tree_code, tree, tree);
147 /* We know that A1 + B1 = SUM1, using 2's complement arithmetic and ignoring
148 overflow. Suppose A, B and SUM have the same respective signs as A1, B1,
149 and SUM1. Then this yields nonzero if overflow occurred during the
152 Overflow occurs if A and B have the same sign, but A and SUM differ in
153 sign. Use `^' to test whether signs differ, and `< 0' to isolate the
155 #define OVERFLOW_SUM_SIGN(a, b, sum) ((~((a) ^ (b)) & ((a) ^ (sum))) < 0)
157 /* To do constant folding on INTEGER_CST nodes requires two-word arithmetic.
158 We do that by representing the two-word integer in 4 words, with only
159 HOST_BITS_PER_WIDE_INT / 2 bits stored in each word, as a positive
160 number. The value of the word is LOWPART + HIGHPART * BASE. */
163 ((x) & (((unsigned HOST_WIDE_INT) 1 << (HOST_BITS_PER_WIDE_INT / 2)) - 1))
164 #define HIGHPART(x) \
165 ((unsigned HOST_WIDE_INT) (x) >> HOST_BITS_PER_WIDE_INT / 2)
166 #define BASE ((unsigned HOST_WIDE_INT) 1 << HOST_BITS_PER_WIDE_INT / 2)
168 /* Unpack a two-word integer into 4 words.
169 LOW and HI are the integer, as two `HOST_WIDE_INT' pieces.
170 WORDS points to the array of HOST_WIDE_INTs. */
173 encode (HOST_WIDE_INT *words, unsigned HOST_WIDE_INT low, HOST_WIDE_INT hi)
175 words[0] = LOWPART (low);
176 words[1] = HIGHPART (low);
177 words[2] = LOWPART (hi);
178 words[3] = HIGHPART (hi);
181 /* Pack an array of 4 words into a two-word integer.
182 WORDS points to the array of words.
183 The integer is stored into *LOW and *HI as two `HOST_WIDE_INT' pieces. */
186 decode (HOST_WIDE_INT *words, unsigned HOST_WIDE_INT *low,
189 *low = words[0] + words[1] * BASE;
190 *hi = words[2] + words[3] * BASE;
193 /* Force the double-word integer L1, H1 to be within the range of the
194 integer type TYPE. Stores the properly truncated and sign-extended
195 double-word integer in *LV, *HV. Returns true if the operation
196 overflows, that is, argument and result are different. */
199 fit_double_type (unsigned HOST_WIDE_INT l1, HOST_WIDE_INT h1,
200 unsigned HOST_WIDE_INT *lv, HOST_WIDE_INT *hv, const_tree type)
202 unsigned HOST_WIDE_INT low0 = l1;
203 HOST_WIDE_INT high0 = h1;
205 int sign_extended_type;
207 if (POINTER_TYPE_P (type)
208 || TREE_CODE (type) == OFFSET_TYPE)
211 prec = TYPE_PRECISION (type);
213 /* Size types *are* sign extended. */
214 sign_extended_type = (!TYPE_UNSIGNED (type)
215 || (TREE_CODE (type) == INTEGER_TYPE
216 && TYPE_IS_SIZETYPE (type)));
218 /* First clear all bits that are beyond the type's precision. */
219 if (prec >= 2 * HOST_BITS_PER_WIDE_INT)
221 else if (prec > HOST_BITS_PER_WIDE_INT)
222 h1 &= ~((HOST_WIDE_INT) (-1) << (prec - HOST_BITS_PER_WIDE_INT));
226 if (prec < HOST_BITS_PER_WIDE_INT)
227 l1 &= ~((HOST_WIDE_INT) (-1) << prec);
230 /* Then do sign extension if necessary. */
231 if (!sign_extended_type)
232 /* No sign extension */;
233 else if (prec >= 2 * HOST_BITS_PER_WIDE_INT)
234 /* Correct width already. */;
235 else if (prec > HOST_BITS_PER_WIDE_INT)
237 /* Sign extend top half? */
238 if (h1 & ((unsigned HOST_WIDE_INT)1
239 << (prec - HOST_BITS_PER_WIDE_INT - 1)))
240 h1 |= (HOST_WIDE_INT) (-1) << (prec - HOST_BITS_PER_WIDE_INT);
242 else if (prec == HOST_BITS_PER_WIDE_INT)
244 if ((HOST_WIDE_INT)l1 < 0)
249 /* Sign extend bottom half? */
250 if (l1 & ((unsigned HOST_WIDE_INT)1 << (prec - 1)))
253 l1 |= (HOST_WIDE_INT)(-1) << prec;
260 /* If the value didn't fit, signal overflow. */
261 return l1 != low0 || h1 != high0;
264 /* We force the double-int HIGH:LOW to the range of the type TYPE by
265 sign or zero extending it.
266 OVERFLOWABLE indicates if we are interested
267 in overflow of the value, when >0 we are only interested in signed
268 overflow, for <0 we are interested in any overflow. OVERFLOWED
269 indicates whether overflow has already occurred. CONST_OVERFLOWED
270 indicates whether constant overflow has already occurred. We force
271 T's value to be within range of T's type (by setting to 0 or 1 all
272 the bits outside the type's range). We set TREE_OVERFLOWED if,
273 OVERFLOWED is nonzero,
274 or OVERFLOWABLE is >0 and signed overflow occurs
275 or OVERFLOWABLE is <0 and any overflow occurs
276 We return a new tree node for the extended double-int. The node
277 is shared if no overflow flags are set. */
280 force_fit_type_double (tree type, unsigned HOST_WIDE_INT low,
281 HOST_WIDE_INT high, int overflowable,
284 int sign_extended_type;
287 /* Size types *are* sign extended. */
288 sign_extended_type = (!TYPE_UNSIGNED (type)
289 || (TREE_CODE (type) == INTEGER_TYPE
290 && TYPE_IS_SIZETYPE (type)));
292 overflow = fit_double_type (low, high, &low, &high, type);
294 /* If we need to set overflow flags, return a new unshared node. */
295 if (overflowed || overflow)
299 || (overflowable > 0 && sign_extended_type))
301 tree t = make_node (INTEGER_CST);
302 TREE_INT_CST_LOW (t) = low;
303 TREE_INT_CST_HIGH (t) = high;
304 TREE_TYPE (t) = type;
305 TREE_OVERFLOW (t) = 1;
310 /* Else build a shared node. */
311 return build_int_cst_wide (type, low, high);
314 /* Add two doubleword integers with doubleword result.
315 Return nonzero if the operation overflows according to UNSIGNED_P.
316 Each argument is given as two `HOST_WIDE_INT' pieces.
317 One argument is L1 and H1; the other, L2 and H2.
318 The value is stored as two `HOST_WIDE_INT' pieces in *LV and *HV. */
321 add_double_with_sign (unsigned HOST_WIDE_INT l1, HOST_WIDE_INT h1,
322 unsigned HOST_WIDE_INT l2, HOST_WIDE_INT h2,
323 unsigned HOST_WIDE_INT *lv, HOST_WIDE_INT *hv,
326 unsigned HOST_WIDE_INT l;
330 h = h1 + h2 + (l < l1);
336 return (unsigned HOST_WIDE_INT) h < (unsigned HOST_WIDE_INT) h1;
338 return OVERFLOW_SUM_SIGN (h1, h2, h);
341 /* Negate a doubleword integer with doubleword result.
342 Return nonzero if the operation overflows, assuming it's signed.
343 The argument is given as two `HOST_WIDE_INT' pieces in L1 and H1.
344 The value is stored as two `HOST_WIDE_INT' pieces in *LV and *HV. */
347 neg_double (unsigned HOST_WIDE_INT l1, HOST_WIDE_INT h1,
348 unsigned HOST_WIDE_INT *lv, HOST_WIDE_INT *hv)
354 return (*hv & h1) < 0;
364 /* Multiply two doubleword integers with doubleword result.
365 Return nonzero if the operation overflows according to UNSIGNED_P.
366 Each argument is given as two `HOST_WIDE_INT' pieces.
367 One argument is L1 and H1; the other, L2 and H2.
368 The value is stored as two `HOST_WIDE_INT' pieces in *LV and *HV. */
371 mul_double_with_sign (unsigned HOST_WIDE_INT l1, HOST_WIDE_INT h1,
372 unsigned HOST_WIDE_INT l2, HOST_WIDE_INT h2,
373 unsigned HOST_WIDE_INT *lv, HOST_WIDE_INT *hv,
376 HOST_WIDE_INT arg1[4];
377 HOST_WIDE_INT arg2[4];
378 HOST_WIDE_INT prod[4 * 2];
379 unsigned HOST_WIDE_INT carry;
381 unsigned HOST_WIDE_INT toplow, neglow;
382 HOST_WIDE_INT tophigh, neghigh;
384 encode (arg1, l1, h1);
385 encode (arg2, l2, h2);
387 memset (prod, 0, sizeof prod);
389 for (i = 0; i < 4; i++)
392 for (j = 0; j < 4; j++)
395 /* This product is <= 0xFFFE0001, the sum <= 0xFFFF0000. */
396 carry += arg1[i] * arg2[j];
397 /* Since prod[p] < 0xFFFF, this sum <= 0xFFFFFFFF. */
399 prod[k] = LOWPART (carry);
400 carry = HIGHPART (carry);
405 decode (prod, lv, hv);
406 decode (prod + 4, &toplow, &tophigh);
408 /* Unsigned overflow is immediate. */
410 return (toplow | tophigh) != 0;
412 /* Check for signed overflow by calculating the signed representation of the
413 top half of the result; it should agree with the low half's sign bit. */
416 neg_double (l2, h2, &neglow, &neghigh);
417 add_double (neglow, neghigh, toplow, tophigh, &toplow, &tophigh);
421 neg_double (l1, h1, &neglow, &neghigh);
422 add_double (neglow, neghigh, toplow, tophigh, &toplow, &tophigh);
424 return (*hv < 0 ? ~(toplow & tophigh) : toplow | tophigh) != 0;
427 /* Shift the doubleword integer in L1, H1 left by COUNT places
428 keeping only PREC bits of result.
429 Shift right if COUNT is negative.
430 ARITH nonzero specifies arithmetic shifting; otherwise use logical shift.
431 Store the value as two `HOST_WIDE_INT' pieces in *LV and *HV. */
434 lshift_double (unsigned HOST_WIDE_INT l1, HOST_WIDE_INT h1,
435 HOST_WIDE_INT count, unsigned int prec,
436 unsigned HOST_WIDE_INT *lv, HOST_WIDE_INT *hv, int arith)
438 unsigned HOST_WIDE_INT signmask;
442 rshift_double (l1, h1, -count, prec, lv, hv, arith);
446 if (SHIFT_COUNT_TRUNCATED)
449 if (count >= 2 * HOST_BITS_PER_WIDE_INT)
451 /* Shifting by the host word size is undefined according to the
452 ANSI standard, so we must handle this as a special case. */
456 else if (count >= HOST_BITS_PER_WIDE_INT)
458 *hv = l1 << (count - HOST_BITS_PER_WIDE_INT);
463 *hv = (((unsigned HOST_WIDE_INT) h1 << count)
464 | (l1 >> (HOST_BITS_PER_WIDE_INT - count - 1) >> 1));
468 /* Sign extend all bits that are beyond the precision. */
470 signmask = -((prec > HOST_BITS_PER_WIDE_INT
471 ? ((unsigned HOST_WIDE_INT) *hv
472 >> (prec - HOST_BITS_PER_WIDE_INT - 1))
473 : (*lv >> (prec - 1))) & 1);
475 if (prec >= 2 * HOST_BITS_PER_WIDE_INT)
477 else if (prec >= HOST_BITS_PER_WIDE_INT)
479 *hv &= ~((HOST_WIDE_INT) (-1) << (prec - HOST_BITS_PER_WIDE_INT));
480 *hv |= signmask << (prec - HOST_BITS_PER_WIDE_INT);
485 *lv &= ~((unsigned HOST_WIDE_INT) (-1) << prec);
486 *lv |= signmask << prec;
490 /* Shift the doubleword integer in L1, H1 right by COUNT places
491 keeping only PREC bits of result. COUNT must be positive.
492 ARITH nonzero specifies arithmetic shifting; otherwise use logical shift.
493 Store the value as two `HOST_WIDE_INT' pieces in *LV and *HV. */
496 rshift_double (unsigned HOST_WIDE_INT l1, HOST_WIDE_INT h1,
497 HOST_WIDE_INT count, unsigned int prec,
498 unsigned HOST_WIDE_INT *lv, HOST_WIDE_INT *hv,
501 unsigned HOST_WIDE_INT signmask;
504 ? -((unsigned HOST_WIDE_INT) h1 >> (HOST_BITS_PER_WIDE_INT - 1))
507 if (SHIFT_COUNT_TRUNCATED)
510 if (count >= 2 * HOST_BITS_PER_WIDE_INT)
512 /* Shifting by the host word size is undefined according to the
513 ANSI standard, so we must handle this as a special case. */
517 else if (count >= HOST_BITS_PER_WIDE_INT)
520 *lv = (unsigned HOST_WIDE_INT) h1 >> (count - HOST_BITS_PER_WIDE_INT);
524 *hv = (unsigned HOST_WIDE_INT) h1 >> count;
526 | ((unsigned HOST_WIDE_INT) h1 << (HOST_BITS_PER_WIDE_INT - count - 1) << 1));
529 /* Zero / sign extend all bits that are beyond the precision. */
531 if (count >= (HOST_WIDE_INT)prec)
536 else if ((prec - count) >= 2 * HOST_BITS_PER_WIDE_INT)
538 else if ((prec - count) >= HOST_BITS_PER_WIDE_INT)
540 *hv &= ~((HOST_WIDE_INT) (-1) << (prec - count - HOST_BITS_PER_WIDE_INT));
541 *hv |= signmask << (prec - count - HOST_BITS_PER_WIDE_INT);
546 *lv &= ~((unsigned HOST_WIDE_INT) (-1) << (prec - count));
547 *lv |= signmask << (prec - count);
551 /* Rotate the doubleword integer in L1, H1 left by COUNT places
552 keeping only PREC bits of result.
553 Rotate right if COUNT is negative.
554 Store the value as two `HOST_WIDE_INT' pieces in *LV and *HV. */
557 lrotate_double (unsigned HOST_WIDE_INT l1, HOST_WIDE_INT h1,
558 HOST_WIDE_INT count, unsigned int prec,
559 unsigned HOST_WIDE_INT *lv, HOST_WIDE_INT *hv)
561 unsigned HOST_WIDE_INT s1l, s2l;
562 HOST_WIDE_INT s1h, s2h;
568 lshift_double (l1, h1, count, prec, &s1l, &s1h, 0);
569 rshift_double (l1, h1, prec - count, prec, &s2l, &s2h, 0);
574 /* Rotate the doubleword integer in L1, H1 left by COUNT places
575 keeping only PREC bits of result. COUNT must be positive.
576 Store the value as two `HOST_WIDE_INT' pieces in *LV and *HV. */
579 rrotate_double (unsigned HOST_WIDE_INT l1, HOST_WIDE_INT h1,
580 HOST_WIDE_INT count, unsigned int prec,
581 unsigned HOST_WIDE_INT *lv, HOST_WIDE_INT *hv)
583 unsigned HOST_WIDE_INT s1l, s2l;
584 HOST_WIDE_INT s1h, s2h;
590 rshift_double (l1, h1, count, prec, &s1l, &s1h, 0);
591 lshift_double (l1, h1, prec - count, prec, &s2l, &s2h, 0);
596 /* Divide doubleword integer LNUM, HNUM by doubleword integer LDEN, HDEN
597 for a quotient (stored in *LQUO, *HQUO) and remainder (in *LREM, *HREM).
598 CODE is a tree code for a kind of division, one of
599 TRUNC_DIV_EXPR, FLOOR_DIV_EXPR, CEIL_DIV_EXPR, ROUND_DIV_EXPR
601 It controls how the quotient is rounded to an integer.
602 Return nonzero if the operation overflows.
603 UNS nonzero says do unsigned division. */
606 div_and_round_double (enum tree_code code, int uns,
607 unsigned HOST_WIDE_INT lnum_orig, /* num == numerator == dividend */
608 HOST_WIDE_INT hnum_orig,
609 unsigned HOST_WIDE_INT lden_orig, /* den == denominator == divisor */
610 HOST_WIDE_INT hden_orig,
611 unsigned HOST_WIDE_INT *lquo,
612 HOST_WIDE_INT *hquo, unsigned HOST_WIDE_INT *lrem,
616 HOST_WIDE_INT num[4 + 1]; /* extra element for scaling. */
617 HOST_WIDE_INT den[4], quo[4];
619 unsigned HOST_WIDE_INT work;
620 unsigned HOST_WIDE_INT carry = 0;
621 unsigned HOST_WIDE_INT lnum = lnum_orig;
622 HOST_WIDE_INT hnum = hnum_orig;
623 unsigned HOST_WIDE_INT lden = lden_orig;
624 HOST_WIDE_INT hden = hden_orig;
627 if (hden == 0 && lden == 0)
628 overflow = 1, lden = 1;
630 /* Calculate quotient sign and convert operands to unsigned. */
636 /* (minimum integer) / (-1) is the only overflow case. */
637 if (neg_double (lnum, hnum, &lnum, &hnum)
638 && ((HOST_WIDE_INT) lden & hden) == -1)
644 neg_double (lden, hden, &lden, &hden);
648 if (hnum == 0 && hden == 0)
649 { /* single precision */
651 /* This unsigned division rounds toward zero. */
657 { /* trivial case: dividend < divisor */
658 /* hden != 0 already checked. */
665 memset (quo, 0, sizeof quo);
667 memset (num, 0, sizeof num); /* to zero 9th element */
668 memset (den, 0, sizeof den);
670 encode (num, lnum, hnum);
671 encode (den, lden, hden);
673 /* Special code for when the divisor < BASE. */
674 if (hden == 0 && lden < (unsigned HOST_WIDE_INT) BASE)
676 /* hnum != 0 already checked. */
677 for (i = 4 - 1; i >= 0; i--)
679 work = num[i] + carry * BASE;
680 quo[i] = work / lden;
686 /* Full double precision division,
687 with thanks to Don Knuth's "Seminumerical Algorithms". */
688 int num_hi_sig, den_hi_sig;
689 unsigned HOST_WIDE_INT quo_est, scale;
691 /* Find the highest nonzero divisor digit. */
692 for (i = 4 - 1;; i--)
699 /* Insure that the first digit of the divisor is at least BASE/2.
700 This is required by the quotient digit estimation algorithm. */
702 scale = BASE / (den[den_hi_sig] + 1);
704 { /* scale divisor and dividend */
706 for (i = 0; i <= 4 - 1; i++)
708 work = (num[i] * scale) + carry;
709 num[i] = LOWPART (work);
710 carry = HIGHPART (work);
715 for (i = 0; i <= 4 - 1; i++)
717 work = (den[i] * scale) + carry;
718 den[i] = LOWPART (work);
719 carry = HIGHPART (work);
720 if (den[i] != 0) den_hi_sig = i;
727 for (i = num_hi_sig - den_hi_sig - 1; i >= 0; i--)
729 /* Guess the next quotient digit, quo_est, by dividing the first
730 two remaining dividend digits by the high order quotient digit.
731 quo_est is never low and is at most 2 high. */
732 unsigned HOST_WIDE_INT tmp;
734 num_hi_sig = i + den_hi_sig + 1;
735 work = num[num_hi_sig] * BASE + num[num_hi_sig - 1];
736 if (num[num_hi_sig] != den[den_hi_sig])
737 quo_est = work / den[den_hi_sig];
741 /* Refine quo_est so it's usually correct, and at most one high. */
742 tmp = work - quo_est * den[den_hi_sig];
744 && (den[den_hi_sig - 1] * quo_est
745 > (tmp * BASE + num[num_hi_sig - 2])))
748 /* Try QUO_EST as the quotient digit, by multiplying the
749 divisor by QUO_EST and subtracting from the remaining dividend.
750 Keep in mind that QUO_EST is the I - 1st digit. */
753 for (j = 0; j <= den_hi_sig; j++)
755 work = quo_est * den[j] + carry;
756 carry = HIGHPART (work);
757 work = num[i + j] - LOWPART (work);
758 num[i + j] = LOWPART (work);
759 carry += HIGHPART (work) != 0;
762 /* If quo_est was high by one, then num[i] went negative and
763 we need to correct things. */
764 if (num[num_hi_sig] < (HOST_WIDE_INT) carry)
767 carry = 0; /* add divisor back in */
768 for (j = 0; j <= den_hi_sig; j++)
770 work = num[i + j] + den[j] + carry;
771 carry = HIGHPART (work);
772 num[i + j] = LOWPART (work);
775 num [num_hi_sig] += carry;
778 /* Store the quotient digit. */
783 decode (quo, lquo, hquo);
786 /* If result is negative, make it so. */
788 neg_double (*lquo, *hquo, lquo, hquo);
790 /* Compute trial remainder: rem = num - (quo * den) */
791 mul_double (*lquo, *hquo, lden_orig, hden_orig, lrem, hrem);
792 neg_double (*lrem, *hrem, lrem, hrem);
793 add_double (lnum_orig, hnum_orig, *lrem, *hrem, lrem, hrem);
798 case TRUNC_MOD_EXPR: /* round toward zero */
799 case EXACT_DIV_EXPR: /* for this one, it shouldn't matter */
803 case FLOOR_MOD_EXPR: /* round toward negative infinity */
804 if (quo_neg && (*lrem != 0 || *hrem != 0)) /* ratio < 0 && rem != 0 */
807 add_double (*lquo, *hquo, (HOST_WIDE_INT) -1, (HOST_WIDE_INT) -1,
815 case CEIL_MOD_EXPR: /* round toward positive infinity */
816 if (!quo_neg && (*lrem != 0 || *hrem != 0)) /* ratio > 0 && rem != 0 */
818 add_double (*lquo, *hquo, (HOST_WIDE_INT) 1, (HOST_WIDE_INT) 0,
826 case ROUND_MOD_EXPR: /* round to closest integer */
828 unsigned HOST_WIDE_INT labs_rem = *lrem;
829 HOST_WIDE_INT habs_rem = *hrem;
830 unsigned HOST_WIDE_INT labs_den = lden, ltwice;
831 HOST_WIDE_INT habs_den = hden, htwice;
833 /* Get absolute values. */
835 neg_double (*lrem, *hrem, &labs_rem, &habs_rem);
837 neg_double (lden, hden, &labs_den, &habs_den);
839 /* If (2 * abs (lrem) >= abs (lden)), adjust the quotient. */
840 mul_double ((HOST_WIDE_INT) 2, (HOST_WIDE_INT) 0,
841 labs_rem, habs_rem, <wice, &htwice);
843 if (((unsigned HOST_WIDE_INT) habs_den
844 < (unsigned HOST_WIDE_INT) htwice)
845 || (((unsigned HOST_WIDE_INT) habs_den
846 == (unsigned HOST_WIDE_INT) htwice)
847 && (labs_den <= ltwice)))
851 add_double (*lquo, *hquo,
852 (HOST_WIDE_INT) -1, (HOST_WIDE_INT) -1, lquo, hquo);
855 add_double (*lquo, *hquo, (HOST_WIDE_INT) 1, (HOST_WIDE_INT) 0,
867 /* Compute true remainder: rem = num - (quo * den) */
868 mul_double (*lquo, *hquo, lden_orig, hden_orig, lrem, hrem);
869 neg_double (*lrem, *hrem, lrem, hrem);
870 add_double (lnum_orig, hnum_orig, *lrem, *hrem, lrem, hrem);
874 /* If ARG2 divides ARG1 with zero remainder, carries out the division
875 of type CODE and returns the quotient.
876 Otherwise returns NULL_TREE. */
879 div_if_zero_remainder (enum tree_code code, const_tree arg1, const_tree arg2)
881 unsigned HOST_WIDE_INT int1l, int2l;
882 HOST_WIDE_INT int1h, int2h;
883 unsigned HOST_WIDE_INT quol, reml;
884 HOST_WIDE_INT quoh, remh;
885 tree type = TREE_TYPE (arg1);
886 int uns = TYPE_UNSIGNED (type);
888 int1l = TREE_INT_CST_LOW (arg1);
889 int1h = TREE_INT_CST_HIGH (arg1);
890 /* &obj[0] + -128 really should be compiled as &obj[-8] rather than
891 &obj[some_exotic_number]. */
892 if (POINTER_TYPE_P (type))
895 type = signed_type_for (type);
896 fit_double_type (int1l, int1h, &int1l, &int1h,
900 fit_double_type (int1l, int1h, &int1l, &int1h, type);
901 int2l = TREE_INT_CST_LOW (arg2);
902 int2h = TREE_INT_CST_HIGH (arg2);
904 div_and_round_double (code, uns, int1l, int1h, int2l, int2h,
905 &quol, &quoh, &reml, &remh);
906 if (remh != 0 || reml != 0)
909 return build_int_cst_wide (type, quol, quoh);
912 /* This is nonzero if we should defer warnings about undefined
913 overflow. This facility exists because these warnings are a
914 special case. The code to estimate loop iterations does not want
915 to issue any warnings, since it works with expressions which do not
916 occur in user code. Various bits of cleanup code call fold(), but
917 only use the result if it has certain characteristics (e.g., is a
918 constant); that code only wants to issue a warning if the result is
921 static int fold_deferring_overflow_warnings;
923 /* If a warning about undefined overflow is deferred, this is the
924 warning. Note that this may cause us to turn two warnings into
925 one, but that is fine since it is sufficient to only give one
926 warning per expression. */
928 static const char* fold_deferred_overflow_warning;
930 /* If a warning about undefined overflow is deferred, this is the
931 level at which the warning should be emitted. */
933 static enum warn_strict_overflow_code fold_deferred_overflow_code;
935 /* Start deferring overflow warnings. We could use a stack here to
936 permit nested calls, but at present it is not necessary. */
939 fold_defer_overflow_warnings (void)
941 ++fold_deferring_overflow_warnings;
944 /* Stop deferring overflow warnings. If there is a pending warning,
945 and ISSUE is true, then issue the warning if appropriate. STMT is
946 the statement with which the warning should be associated (used for
947 location information); STMT may be NULL. CODE is the level of the
948 warning--a warn_strict_overflow_code value. This function will use
949 the smaller of CODE and the deferred code when deciding whether to
950 issue the warning. CODE may be zero to mean to always use the
954 fold_undefer_overflow_warnings (bool issue, const_gimple stmt, int code)
959 gcc_assert (fold_deferring_overflow_warnings > 0);
960 --fold_deferring_overflow_warnings;
961 if (fold_deferring_overflow_warnings > 0)
963 if (fold_deferred_overflow_warning != NULL
965 && code < (int) fold_deferred_overflow_code)
966 fold_deferred_overflow_code = code;
970 warnmsg = fold_deferred_overflow_warning;
971 fold_deferred_overflow_warning = NULL;
973 if (!issue || warnmsg == NULL)
976 if (gimple_no_warning_p (stmt))
979 /* Use the smallest code level when deciding to issue the
981 if (code == 0 || code > (int) fold_deferred_overflow_code)
982 code = fold_deferred_overflow_code;
984 if (!issue_strict_overflow_warning (code))
988 locus = input_location;
990 locus = gimple_location (stmt);
991 warning (OPT_Wstrict_overflow, "%H%s", &locus, warnmsg);
994 /* Stop deferring overflow warnings, ignoring any deferred
998 fold_undefer_and_ignore_overflow_warnings (void)
1000 fold_undefer_overflow_warnings (false, NULL, 0);
1003 /* Whether we are deferring overflow warnings. */
1006 fold_deferring_overflow_warnings_p (void)
1008 return fold_deferring_overflow_warnings > 0;
1011 /* This is called when we fold something based on the fact that signed
1012 overflow is undefined. */
1015 fold_overflow_warning (const char* gmsgid, enum warn_strict_overflow_code wc)
1017 if (fold_deferring_overflow_warnings > 0)
1019 if (fold_deferred_overflow_warning == NULL
1020 || wc < fold_deferred_overflow_code)
1022 fold_deferred_overflow_warning = gmsgid;
1023 fold_deferred_overflow_code = wc;
1026 else if (issue_strict_overflow_warning (wc))
1027 warning (OPT_Wstrict_overflow, gmsgid);
1030 /* Return true if the built-in mathematical function specified by CODE
1031 is odd, i.e. -f(x) == f(-x). */
1034 negate_mathfn_p (enum built_in_function code)
1038 CASE_FLT_FN (BUILT_IN_ASIN):
1039 CASE_FLT_FN (BUILT_IN_ASINH):
1040 CASE_FLT_FN (BUILT_IN_ATAN):
1041 CASE_FLT_FN (BUILT_IN_ATANH):
1042 CASE_FLT_FN (BUILT_IN_CASIN):
1043 CASE_FLT_FN (BUILT_IN_CASINH):
1044 CASE_FLT_FN (BUILT_IN_CATAN):
1045 CASE_FLT_FN (BUILT_IN_CATANH):
1046 CASE_FLT_FN (BUILT_IN_CBRT):
1047 CASE_FLT_FN (BUILT_IN_CPROJ):
1048 CASE_FLT_FN (BUILT_IN_CSIN):
1049 CASE_FLT_FN (BUILT_IN_CSINH):
1050 CASE_FLT_FN (BUILT_IN_CTAN):
1051 CASE_FLT_FN (BUILT_IN_CTANH):
1052 CASE_FLT_FN (BUILT_IN_ERF):
1053 CASE_FLT_FN (BUILT_IN_LLROUND):
1054 CASE_FLT_FN (BUILT_IN_LROUND):
1055 CASE_FLT_FN (BUILT_IN_ROUND):
1056 CASE_FLT_FN (BUILT_IN_SIN):
1057 CASE_FLT_FN (BUILT_IN_SINH):
1058 CASE_FLT_FN (BUILT_IN_TAN):
1059 CASE_FLT_FN (BUILT_IN_TANH):
1060 CASE_FLT_FN (BUILT_IN_TRUNC):
1063 CASE_FLT_FN (BUILT_IN_LLRINT):
1064 CASE_FLT_FN (BUILT_IN_LRINT):
1065 CASE_FLT_FN (BUILT_IN_NEARBYINT):
1066 CASE_FLT_FN (BUILT_IN_RINT):
1067 return !flag_rounding_math;
1075 /* Check whether we may negate an integer constant T without causing
1079 may_negate_without_overflow_p (const_tree t)
1081 unsigned HOST_WIDE_INT val;
1085 gcc_assert (TREE_CODE (t) == INTEGER_CST);
1087 type = TREE_TYPE (t);
1088 if (TYPE_UNSIGNED (type))
1091 prec = TYPE_PRECISION (type);
1092 if (prec > HOST_BITS_PER_WIDE_INT)
1094 if (TREE_INT_CST_LOW (t) != 0)
1096 prec -= HOST_BITS_PER_WIDE_INT;
1097 val = TREE_INT_CST_HIGH (t);
1100 val = TREE_INT_CST_LOW (t);
1101 if (prec < HOST_BITS_PER_WIDE_INT)
1102 val &= ((unsigned HOST_WIDE_INT) 1 << prec) - 1;
1103 return val != ((unsigned HOST_WIDE_INT) 1 << (prec - 1));
1106 /* Determine whether an expression T can be cheaply negated using
1107 the function negate_expr without introducing undefined overflow. */
1110 negate_expr_p (tree t)
1117 type = TREE_TYPE (t);
1119 STRIP_SIGN_NOPS (t);
1120 switch (TREE_CODE (t))
1123 if (TYPE_OVERFLOW_WRAPS (type))
1126 /* Check that -CST will not overflow type. */
1127 return may_negate_without_overflow_p (t);
1129 return (INTEGRAL_TYPE_P (type)
1130 && TYPE_OVERFLOW_WRAPS (type));
1138 return negate_expr_p (TREE_REALPART (t))
1139 && negate_expr_p (TREE_IMAGPART (t));
1142 return negate_expr_p (TREE_OPERAND (t, 0))
1143 && negate_expr_p (TREE_OPERAND (t, 1));
1146 return negate_expr_p (TREE_OPERAND (t, 0));
1149 if (HONOR_SIGN_DEPENDENT_ROUNDING (TYPE_MODE (type))
1150 || HONOR_SIGNED_ZEROS (TYPE_MODE (type)))
1152 /* -(A + B) -> (-B) - A. */
1153 if (negate_expr_p (TREE_OPERAND (t, 1))
1154 && reorder_operands_p (TREE_OPERAND (t, 0),
1155 TREE_OPERAND (t, 1)))
1157 /* -(A + B) -> (-A) - B. */
1158 return negate_expr_p (TREE_OPERAND (t, 0));
1161 /* We can't turn -(A-B) into B-A when we honor signed zeros. */
1162 return !HONOR_SIGN_DEPENDENT_ROUNDING (TYPE_MODE (type))
1163 && !HONOR_SIGNED_ZEROS (TYPE_MODE (type))
1164 && reorder_operands_p (TREE_OPERAND (t, 0),
1165 TREE_OPERAND (t, 1));
1168 if (TYPE_UNSIGNED (TREE_TYPE (t)))
1174 if (! HONOR_SIGN_DEPENDENT_ROUNDING (TYPE_MODE (TREE_TYPE (t))))
1175 return negate_expr_p (TREE_OPERAND (t, 1))
1176 || negate_expr_p (TREE_OPERAND (t, 0));
1179 case TRUNC_DIV_EXPR:
1180 case ROUND_DIV_EXPR:
1181 case FLOOR_DIV_EXPR:
1183 case EXACT_DIV_EXPR:
1184 /* In general we can't negate A / B, because if A is INT_MIN and
1185 B is 1, we may turn this into INT_MIN / -1 which is undefined
1186 and actually traps on some architectures. But if overflow is
1187 undefined, we can negate, because - (INT_MIN / 1) is an
1189 if (INTEGRAL_TYPE_P (TREE_TYPE (t))
1190 && !TYPE_OVERFLOW_UNDEFINED (TREE_TYPE (t)))
1192 return negate_expr_p (TREE_OPERAND (t, 1))
1193 || negate_expr_p (TREE_OPERAND (t, 0));
1196 /* Negate -((double)float) as (double)(-float). */
1197 if (TREE_CODE (type) == REAL_TYPE)
1199 tree tem = strip_float_extensions (t);
1201 return negate_expr_p (tem);
1206 /* Negate -f(x) as f(-x). */
1207 if (negate_mathfn_p (builtin_mathfn_code (t)))
1208 return negate_expr_p (CALL_EXPR_ARG (t, 0));
1212 /* Optimize -((int)x >> 31) into (unsigned)x >> 31. */
1213 if (TREE_CODE (TREE_OPERAND (t, 1)) == INTEGER_CST)
1215 tree op1 = TREE_OPERAND (t, 1);
1216 if (TREE_INT_CST_HIGH (op1) == 0
1217 && (unsigned HOST_WIDE_INT) (TYPE_PRECISION (type) - 1)
1218 == TREE_INT_CST_LOW (op1))
1229 /* Given T, an expression, return a folded tree for -T or NULL_TREE, if no
1230 simplification is possible.
1231 If negate_expr_p would return true for T, NULL_TREE will never be
1235 fold_negate_expr (tree t)
1237 tree type = TREE_TYPE (t);
1240 switch (TREE_CODE (t))
1242 /* Convert - (~A) to A + 1. */
1244 if (INTEGRAL_TYPE_P (type))
1245 return fold_build2 (PLUS_EXPR, type, TREE_OPERAND (t, 0),
1246 build_int_cst (type, 1));
1250 tem = fold_negate_const (t, type);
1251 if (TREE_OVERFLOW (tem) == TREE_OVERFLOW (t)
1252 || !TYPE_OVERFLOW_TRAPS (type))
1257 tem = fold_negate_const (t, type);
1258 /* Two's complement FP formats, such as c4x, may overflow. */
1259 if (!TREE_OVERFLOW (tem) || !flag_trapping_math)
1264 tem = fold_negate_const (t, type);
1269 tree rpart = negate_expr (TREE_REALPART (t));
1270 tree ipart = negate_expr (TREE_IMAGPART (t));
1272 if ((TREE_CODE (rpart) == REAL_CST
1273 && TREE_CODE (ipart) == REAL_CST)
1274 || (TREE_CODE (rpart) == INTEGER_CST
1275 && TREE_CODE (ipart) == INTEGER_CST))
1276 return build_complex (type, rpart, ipart);
1281 if (negate_expr_p (t))
1282 return fold_build2 (COMPLEX_EXPR, type,
1283 fold_negate_expr (TREE_OPERAND (t, 0)),
1284 fold_negate_expr (TREE_OPERAND (t, 1)));
1288 if (negate_expr_p (t))
1289 return fold_build1 (CONJ_EXPR, type,
1290 fold_negate_expr (TREE_OPERAND (t, 0)));
1294 return TREE_OPERAND (t, 0);
1297 if (!HONOR_SIGN_DEPENDENT_ROUNDING (TYPE_MODE (type))
1298 && !HONOR_SIGNED_ZEROS (TYPE_MODE (type)))
1300 /* -(A + B) -> (-B) - A. */
1301 if (negate_expr_p (TREE_OPERAND (t, 1))
1302 && reorder_operands_p (TREE_OPERAND (t, 0),
1303 TREE_OPERAND (t, 1)))
1305 tem = negate_expr (TREE_OPERAND (t, 1));
1306 return fold_build2 (MINUS_EXPR, type,
1307 tem, TREE_OPERAND (t, 0));
1310 /* -(A + B) -> (-A) - B. */
1311 if (negate_expr_p (TREE_OPERAND (t, 0)))
1313 tem = negate_expr (TREE_OPERAND (t, 0));
1314 return fold_build2 (MINUS_EXPR, type,
1315 tem, TREE_OPERAND (t, 1));
1321 /* - (A - B) -> B - A */
1322 if (!HONOR_SIGN_DEPENDENT_ROUNDING (TYPE_MODE (type))
1323 && !HONOR_SIGNED_ZEROS (TYPE_MODE (type))
1324 && reorder_operands_p (TREE_OPERAND (t, 0), TREE_OPERAND (t, 1)))
1325 return fold_build2 (MINUS_EXPR, type,
1326 TREE_OPERAND (t, 1), TREE_OPERAND (t, 0));
1330 if (TYPE_UNSIGNED (type))
1336 if (! HONOR_SIGN_DEPENDENT_ROUNDING (TYPE_MODE (type)))
1338 tem = TREE_OPERAND (t, 1);
1339 if (negate_expr_p (tem))
1340 return fold_build2 (TREE_CODE (t), type,
1341 TREE_OPERAND (t, 0), negate_expr (tem));
1342 tem = TREE_OPERAND (t, 0);
1343 if (negate_expr_p (tem))
1344 return fold_build2 (TREE_CODE (t), type,
1345 negate_expr (tem), TREE_OPERAND (t, 1));
1349 case TRUNC_DIV_EXPR:
1350 case ROUND_DIV_EXPR:
1351 case FLOOR_DIV_EXPR:
1353 case EXACT_DIV_EXPR:
1354 /* In general we can't negate A / B, because if A is INT_MIN and
1355 B is 1, we may turn this into INT_MIN / -1 which is undefined
1356 and actually traps on some architectures. But if overflow is
1357 undefined, we can negate, because - (INT_MIN / 1) is an
1359 if (!INTEGRAL_TYPE_P (type) || TYPE_OVERFLOW_UNDEFINED (type))
1361 const char * const warnmsg = G_("assuming signed overflow does not "
1362 "occur when negating a division");
1363 tem = TREE_OPERAND (t, 1);
1364 if (negate_expr_p (tem))
1366 if (INTEGRAL_TYPE_P (type)
1367 && (TREE_CODE (tem) != INTEGER_CST
1368 || integer_onep (tem)))
1369 fold_overflow_warning (warnmsg, WARN_STRICT_OVERFLOW_MISC);
1370 return fold_build2 (TREE_CODE (t), type,
1371 TREE_OPERAND (t, 0), negate_expr (tem));
1373 tem = TREE_OPERAND (t, 0);
1374 if (negate_expr_p (tem))
1376 if (INTEGRAL_TYPE_P (type)
1377 && (TREE_CODE (tem) != INTEGER_CST
1378 || tree_int_cst_equal (tem, TYPE_MIN_VALUE (type))))
1379 fold_overflow_warning (warnmsg, WARN_STRICT_OVERFLOW_MISC);
1380 return fold_build2 (TREE_CODE (t), type,
1381 negate_expr (tem), TREE_OPERAND (t, 1));
1387 /* Convert -((double)float) into (double)(-float). */
1388 if (TREE_CODE (type) == REAL_TYPE)
1390 tem = strip_float_extensions (t);
1391 if (tem != t && negate_expr_p (tem))
1392 return fold_convert (type, negate_expr (tem));
1397 /* Negate -f(x) as f(-x). */
1398 if (negate_mathfn_p (builtin_mathfn_code (t))
1399 && negate_expr_p (CALL_EXPR_ARG (t, 0)))
1403 fndecl = get_callee_fndecl (t);
1404 arg = negate_expr (CALL_EXPR_ARG (t, 0));
1405 return build_call_expr (fndecl, 1, arg);
1410 /* Optimize -((int)x >> 31) into (unsigned)x >> 31. */
1411 if (TREE_CODE (TREE_OPERAND (t, 1)) == INTEGER_CST)
1413 tree op1 = TREE_OPERAND (t, 1);
1414 if (TREE_INT_CST_HIGH (op1) == 0
1415 && (unsigned HOST_WIDE_INT) (TYPE_PRECISION (type) - 1)
1416 == TREE_INT_CST_LOW (op1))
1418 tree ntype = TYPE_UNSIGNED (type)
1419 ? signed_type_for (type)
1420 : unsigned_type_for (type);
1421 tree temp = fold_convert (ntype, TREE_OPERAND (t, 0));
1422 temp = fold_build2 (RSHIFT_EXPR, ntype, temp, op1);
1423 return fold_convert (type, temp);
1435 /* Like fold_negate_expr, but return a NEGATE_EXPR tree, if T can not be
1436 negated in a simpler way. Also allow for T to be NULL_TREE, in which case
1437 return NULL_TREE. */
1440 negate_expr (tree t)
1447 type = TREE_TYPE (t);
1448 STRIP_SIGN_NOPS (t);
1450 tem = fold_negate_expr (t);
1452 tem = build1 (NEGATE_EXPR, TREE_TYPE (t), t);
1453 return fold_convert (type, tem);
1456 /* Split a tree IN into a constant, literal and variable parts that could be
1457 combined with CODE to make IN. "constant" means an expression with
1458 TREE_CONSTANT but that isn't an actual constant. CODE must be a
1459 commutative arithmetic operation. Store the constant part into *CONP,
1460 the literal in *LITP and return the variable part. If a part isn't
1461 present, set it to null. If the tree does not decompose in this way,
1462 return the entire tree as the variable part and the other parts as null.
1464 If CODE is PLUS_EXPR we also split trees that use MINUS_EXPR. In that
1465 case, we negate an operand that was subtracted. Except if it is a
1466 literal for which we use *MINUS_LITP instead.
1468 If NEGATE_P is true, we are negating all of IN, again except a literal
1469 for which we use *MINUS_LITP instead.
1471 If IN is itself a literal or constant, return it as appropriate.
1473 Note that we do not guarantee that any of the three values will be the
1474 same type as IN, but they will have the same signedness and mode. */
1477 split_tree (tree in, enum tree_code code, tree *conp, tree *litp,
1478 tree *minus_litp, int negate_p)
1486 /* Strip any conversions that don't change the machine mode or signedness. */
1487 STRIP_SIGN_NOPS (in);
1489 if (TREE_CODE (in) == INTEGER_CST || TREE_CODE (in) == REAL_CST
1490 || TREE_CODE (in) == FIXED_CST)
1492 else if (TREE_CODE (in) == code
1493 || ((! FLOAT_TYPE_P (TREE_TYPE (in)) || flag_associative_math)
1494 && ! SAT_FIXED_POINT_TYPE_P (TREE_TYPE (in))
1495 /* We can associate addition and subtraction together (even
1496 though the C standard doesn't say so) for integers because
1497 the value is not affected. For reals, the value might be
1498 affected, so we can't. */
1499 && ((code == PLUS_EXPR && TREE_CODE (in) == MINUS_EXPR)
1500 || (code == MINUS_EXPR && TREE_CODE (in) == PLUS_EXPR))))
1502 tree op0 = TREE_OPERAND (in, 0);
1503 tree op1 = TREE_OPERAND (in, 1);
1504 int neg1_p = TREE_CODE (in) == MINUS_EXPR;
1505 int neg_litp_p = 0, neg_conp_p = 0, neg_var_p = 0;
1507 /* First see if either of the operands is a literal, then a constant. */
1508 if (TREE_CODE (op0) == INTEGER_CST || TREE_CODE (op0) == REAL_CST
1509 || TREE_CODE (op0) == FIXED_CST)
1510 *litp = op0, op0 = 0;
1511 else if (TREE_CODE (op1) == INTEGER_CST || TREE_CODE (op1) == REAL_CST
1512 || TREE_CODE (op1) == FIXED_CST)
1513 *litp = op1, neg_litp_p = neg1_p, op1 = 0;
1515 if (op0 != 0 && TREE_CONSTANT (op0))
1516 *conp = op0, op0 = 0;
1517 else if (op1 != 0 && TREE_CONSTANT (op1))
1518 *conp = op1, neg_conp_p = neg1_p, op1 = 0;
1520 /* If we haven't dealt with either operand, this is not a case we can
1521 decompose. Otherwise, VAR is either of the ones remaining, if any. */
1522 if (op0 != 0 && op1 != 0)
1527 var = op1, neg_var_p = neg1_p;
1529 /* Now do any needed negations. */
1531 *minus_litp = *litp, *litp = 0;
1533 *conp = negate_expr (*conp);
1535 var = negate_expr (var);
1537 else if (TREE_CONSTANT (in))
1545 *minus_litp = *litp, *litp = 0;
1546 else if (*minus_litp)
1547 *litp = *minus_litp, *minus_litp = 0;
1548 *conp = negate_expr (*conp);
1549 var = negate_expr (var);
1555 /* Re-associate trees split by the above function. T1 and T2 are either
1556 expressions to associate or null. Return the new expression, if any. If
1557 we build an operation, do it in TYPE and with CODE. */
1560 associate_trees (tree t1, tree t2, enum tree_code code, tree type)
1567 /* If either input is CODE, a PLUS_EXPR, or a MINUS_EXPR, don't
1568 try to fold this since we will have infinite recursion. But do
1569 deal with any NEGATE_EXPRs. */
1570 if (TREE_CODE (t1) == code || TREE_CODE (t2) == code
1571 || TREE_CODE (t1) == MINUS_EXPR || TREE_CODE (t2) == MINUS_EXPR)
1573 if (code == PLUS_EXPR)
1575 if (TREE_CODE (t1) == NEGATE_EXPR)
1576 return build2 (MINUS_EXPR, type, fold_convert (type, t2),
1577 fold_convert (type, TREE_OPERAND (t1, 0)));
1578 else if (TREE_CODE (t2) == NEGATE_EXPR)
1579 return build2 (MINUS_EXPR, type, fold_convert (type, t1),
1580 fold_convert (type, TREE_OPERAND (t2, 0)));
1581 else if (integer_zerop (t2))
1582 return fold_convert (type, t1);
1584 else if (code == MINUS_EXPR)
1586 if (integer_zerop (t2))
1587 return fold_convert (type, t1);
1590 return build2 (code, type, fold_convert (type, t1),
1591 fold_convert (type, t2));
1594 return fold_build2 (code, type, fold_convert (type, t1),
1595 fold_convert (type, t2));
1598 /* Check whether TYPE1 and TYPE2 are equivalent integer types, suitable
1599 for use in int_const_binop, size_binop and size_diffop. */
1602 int_binop_types_match_p (enum tree_code code, const_tree type1, const_tree type2)
1604 if (TREE_CODE (type1) != INTEGER_TYPE && !POINTER_TYPE_P (type1))
1606 if (TREE_CODE (type2) != INTEGER_TYPE && !POINTER_TYPE_P (type2))
1621 return TYPE_UNSIGNED (type1) == TYPE_UNSIGNED (type2)
1622 && TYPE_PRECISION (type1) == TYPE_PRECISION (type2)
1623 && TYPE_MODE (type1) == TYPE_MODE (type2);
1627 /* Combine two integer constants ARG1 and ARG2 under operation CODE
1628 to produce a new constant. Return NULL_TREE if we don't know how
1629 to evaluate CODE at compile-time.
1631 If NOTRUNC is nonzero, do not truncate the result to fit the data type. */
1634 int_const_binop (enum tree_code code, const_tree arg1, const_tree arg2, int notrunc)
1636 unsigned HOST_WIDE_INT int1l, int2l;
1637 HOST_WIDE_INT int1h, int2h;
1638 unsigned HOST_WIDE_INT low;
1640 unsigned HOST_WIDE_INT garbagel;
1641 HOST_WIDE_INT garbageh;
1643 tree type = TREE_TYPE (arg1);
1644 int uns = TYPE_UNSIGNED (type);
1646 = (TREE_CODE (type) == INTEGER_TYPE && TYPE_IS_SIZETYPE (type));
1649 int1l = TREE_INT_CST_LOW (arg1);
1650 int1h = TREE_INT_CST_HIGH (arg1);
1651 int2l = TREE_INT_CST_LOW (arg2);
1652 int2h = TREE_INT_CST_HIGH (arg2);
1657 low = int1l | int2l, hi = int1h | int2h;
1661 low = int1l ^ int2l, hi = int1h ^ int2h;
1665 low = int1l & int2l, hi = int1h & int2h;
1671 /* It's unclear from the C standard whether shifts can overflow.
1672 The following code ignores overflow; perhaps a C standard
1673 interpretation ruling is needed. */
1674 lshift_double (int1l, int1h, int2l, TYPE_PRECISION (type),
1681 lrotate_double (int1l, int1h, int2l, TYPE_PRECISION (type),
1686 overflow = add_double (int1l, int1h, int2l, int2h, &low, &hi);
1690 neg_double (int2l, int2h, &low, &hi);
1691 add_double (int1l, int1h, low, hi, &low, &hi);
1692 overflow = OVERFLOW_SUM_SIGN (hi, int2h, int1h);
1696 overflow = mul_double (int1l, int1h, int2l, int2h, &low, &hi);
1699 case TRUNC_DIV_EXPR:
1700 case FLOOR_DIV_EXPR: case CEIL_DIV_EXPR:
1701 case EXACT_DIV_EXPR:
1702 /* This is a shortcut for a common special case. */
1703 if (int2h == 0 && (HOST_WIDE_INT) int2l > 0
1704 && !TREE_OVERFLOW (arg1)
1705 && !TREE_OVERFLOW (arg2)
1706 && int1h == 0 && (HOST_WIDE_INT) int1l >= 0)
1708 if (code == CEIL_DIV_EXPR)
1711 low = int1l / int2l, hi = 0;
1715 /* ... fall through ... */
1717 case ROUND_DIV_EXPR:
1718 if (int2h == 0 && int2l == 0)
1720 if (int2h == 0 && int2l == 1)
1722 low = int1l, hi = int1h;
1725 if (int1l == int2l && int1h == int2h
1726 && ! (int1l == 0 && int1h == 0))
1731 overflow = div_and_round_double (code, uns, int1l, int1h, int2l, int2h,
1732 &low, &hi, &garbagel, &garbageh);
1735 case TRUNC_MOD_EXPR:
1736 case FLOOR_MOD_EXPR: case CEIL_MOD_EXPR:
1737 /* This is a shortcut for a common special case. */
1738 if (int2h == 0 && (HOST_WIDE_INT) int2l > 0
1739 && !TREE_OVERFLOW (arg1)
1740 && !TREE_OVERFLOW (arg2)
1741 && int1h == 0 && (HOST_WIDE_INT) int1l >= 0)
1743 if (code == CEIL_MOD_EXPR)
1745 low = int1l % int2l, hi = 0;
1749 /* ... fall through ... */
1751 case ROUND_MOD_EXPR:
1752 if (int2h == 0 && int2l == 0)
1754 overflow = div_and_round_double (code, uns,
1755 int1l, int1h, int2l, int2h,
1756 &garbagel, &garbageh, &low, &hi);
1762 low = (((unsigned HOST_WIDE_INT) int1h
1763 < (unsigned HOST_WIDE_INT) int2h)
1764 || (((unsigned HOST_WIDE_INT) int1h
1765 == (unsigned HOST_WIDE_INT) int2h)
1768 low = (int1h < int2h
1769 || (int1h == int2h && int1l < int2l));
1771 if (low == (code == MIN_EXPR))
1772 low = int1l, hi = int1h;
1774 low = int2l, hi = int2h;
1783 t = build_int_cst_wide (TREE_TYPE (arg1), low, hi);
1785 /* Propagate overflow flags ourselves. */
1786 if (((!uns || is_sizetype) && overflow)
1787 | TREE_OVERFLOW (arg1) | TREE_OVERFLOW (arg2))
1790 TREE_OVERFLOW (t) = 1;
1794 t = force_fit_type_double (TREE_TYPE (arg1), low, hi, 1,
1795 ((!uns || is_sizetype) && overflow)
1796 | TREE_OVERFLOW (arg1) | TREE_OVERFLOW (arg2));
1801 /* Combine two constants ARG1 and ARG2 under operation CODE to produce a new
1802 constant. We assume ARG1 and ARG2 have the same data type, or at least
1803 are the same kind of constant and the same machine mode. Return zero if
1804 combining the constants is not allowed in the current operating mode.
1806 If NOTRUNC is nonzero, do not truncate the result to fit the data type. */
1809 const_binop (enum tree_code code, tree arg1, tree arg2, int notrunc)
1811 /* Sanity check for the recursive cases. */
1818 if (TREE_CODE (arg1) == INTEGER_CST)
1819 return int_const_binop (code, arg1, arg2, notrunc);
1821 if (TREE_CODE (arg1) == REAL_CST)
1823 enum machine_mode mode;
1826 REAL_VALUE_TYPE value;
1827 REAL_VALUE_TYPE result;
1831 /* The following codes are handled by real_arithmetic. */
1846 d1 = TREE_REAL_CST (arg1);
1847 d2 = TREE_REAL_CST (arg2);
1849 type = TREE_TYPE (arg1);
1850 mode = TYPE_MODE (type);
1852 /* Don't perform operation if we honor signaling NaNs and
1853 either operand is a NaN. */
1854 if (HONOR_SNANS (mode)
1855 && (REAL_VALUE_ISNAN (d1) || REAL_VALUE_ISNAN (d2)))
1858 /* Don't perform operation if it would raise a division
1859 by zero exception. */
1860 if (code == RDIV_EXPR
1861 && REAL_VALUES_EQUAL (d2, dconst0)
1862 && (flag_trapping_math || ! MODE_HAS_INFINITIES (mode)))
1865 /* If either operand is a NaN, just return it. Otherwise, set up
1866 for floating-point trap; we return an overflow. */
1867 if (REAL_VALUE_ISNAN (d1))
1869 else if (REAL_VALUE_ISNAN (d2))
1872 inexact = real_arithmetic (&value, code, &d1, &d2);
1873 real_convert (&result, mode, &value);
1875 /* Don't constant fold this floating point operation if
1876 the result has overflowed and flag_trapping_math. */
1877 if (flag_trapping_math
1878 && MODE_HAS_INFINITIES (mode)
1879 && REAL_VALUE_ISINF (result)
1880 && !REAL_VALUE_ISINF (d1)
1881 && !REAL_VALUE_ISINF (d2))
1884 /* Don't constant fold this floating point operation if the
1885 result may dependent upon the run-time rounding mode and
1886 flag_rounding_math is set, or if GCC's software emulation
1887 is unable to accurately represent the result. */
1888 if ((flag_rounding_math
1889 || (MODE_COMPOSITE_P (mode) && !flag_unsafe_math_optimizations))
1890 && (inexact || !real_identical (&result, &value)))
1893 t = build_real (type, result);
1895 TREE_OVERFLOW (t) = TREE_OVERFLOW (arg1) | TREE_OVERFLOW (arg2);
1899 if (TREE_CODE (arg1) == FIXED_CST)
1901 FIXED_VALUE_TYPE f1;
1902 FIXED_VALUE_TYPE f2;
1903 FIXED_VALUE_TYPE result;
1908 /* The following codes are handled by fixed_arithmetic. */
1914 case TRUNC_DIV_EXPR:
1915 f2 = TREE_FIXED_CST (arg2);
1920 f2.data.high = TREE_INT_CST_HIGH (arg2);
1921 f2.data.low = TREE_INT_CST_LOW (arg2);
1929 f1 = TREE_FIXED_CST (arg1);
1930 type = TREE_TYPE (arg1);
1931 sat_p = TYPE_SATURATING (type);
1932 overflow_p = fixed_arithmetic (&result, code, &f1, &f2, sat_p);
1933 t = build_fixed (type, result);
1934 /* Propagate overflow flags. */
1935 if (overflow_p | TREE_OVERFLOW (arg1) | TREE_OVERFLOW (arg2))
1936 TREE_OVERFLOW (t) = 1;
1940 if (TREE_CODE (arg1) == COMPLEX_CST)
1942 tree type = TREE_TYPE (arg1);
1943 tree r1 = TREE_REALPART (arg1);
1944 tree i1 = TREE_IMAGPART (arg1);
1945 tree r2 = TREE_REALPART (arg2);
1946 tree i2 = TREE_IMAGPART (arg2);
1953 real = const_binop (code, r1, r2, notrunc);
1954 imag = const_binop (code, i1, i2, notrunc);
1958 real = const_binop (MINUS_EXPR,
1959 const_binop (MULT_EXPR, r1, r2, notrunc),
1960 const_binop (MULT_EXPR, i1, i2, notrunc),
1962 imag = const_binop (PLUS_EXPR,
1963 const_binop (MULT_EXPR, r1, i2, notrunc),
1964 const_binop (MULT_EXPR, i1, r2, notrunc),
1971 = const_binop (PLUS_EXPR,
1972 const_binop (MULT_EXPR, r2, r2, notrunc),
1973 const_binop (MULT_EXPR, i2, i2, notrunc),
1976 = const_binop (PLUS_EXPR,
1977 const_binop (MULT_EXPR, r1, r2, notrunc),
1978 const_binop (MULT_EXPR, i1, i2, notrunc),
1981 = const_binop (MINUS_EXPR,
1982 const_binop (MULT_EXPR, i1, r2, notrunc),
1983 const_binop (MULT_EXPR, r1, i2, notrunc),
1986 if (INTEGRAL_TYPE_P (TREE_TYPE (r1)))
1987 code = TRUNC_DIV_EXPR;
1989 real = const_binop (code, t1, magsquared, notrunc);
1990 imag = const_binop (code, t2, magsquared, notrunc);
1999 return build_complex (type, real, imag);
2002 if (TREE_CODE (arg1) == VECTOR_CST)
2004 tree type = TREE_TYPE(arg1);
2005 int count = TYPE_VECTOR_SUBPARTS (type), i;
2006 tree elements1, elements2, list = NULL_TREE;
2008 if(TREE_CODE(arg2) != VECTOR_CST)
2011 elements1 = TREE_VECTOR_CST_ELTS (arg1);
2012 elements2 = TREE_VECTOR_CST_ELTS (arg2);
2014 for (i = 0; i < count; i++)
2016 tree elem1, elem2, elem;
2018 /* The trailing elements can be empty and should be treated as 0 */
2020 elem1 = fold_convert_const (NOP_EXPR, TREE_TYPE (type), integer_zero_node);
2023 elem1 = TREE_VALUE(elements1);
2024 elements1 = TREE_CHAIN (elements1);
2028 elem2 = fold_convert_const (NOP_EXPR, TREE_TYPE (type), integer_zero_node);
2031 elem2 = TREE_VALUE(elements2);
2032 elements2 = TREE_CHAIN (elements2);
2035 elem = const_binop (code, elem1, elem2, notrunc);
2037 /* It is possible that const_binop cannot handle the given
2038 code and return NULL_TREE */
2039 if(elem == NULL_TREE)
2042 list = tree_cons (NULL_TREE, elem, list);
2044 return build_vector(type, nreverse(list));
2049 /* Create a size type INT_CST node with NUMBER sign extended. KIND
2050 indicates which particular sizetype to create. */
2053 size_int_kind (HOST_WIDE_INT number, enum size_type_kind kind)
2055 return build_int_cst (sizetype_tab[(int) kind], number);
2058 /* Combine operands OP1 and OP2 with arithmetic operation CODE. CODE
2059 is a tree code. The type of the result is taken from the operands.
2060 Both must be equivalent integer types, ala int_binop_types_match_p.
2061 If the operands are constant, so is the result. */
2064 size_binop (enum tree_code code, tree arg0, tree arg1)
2066 tree type = TREE_TYPE (arg0);
2068 if (arg0 == error_mark_node || arg1 == error_mark_node)
2069 return error_mark_node;
2071 gcc_assert (int_binop_types_match_p (code, TREE_TYPE (arg0),
2074 /* Handle the special case of two integer constants faster. */
2075 if (TREE_CODE (arg0) == INTEGER_CST && TREE_CODE (arg1) == INTEGER_CST)
2077 /* And some specific cases even faster than that. */
2078 if (code == PLUS_EXPR)
2080 if (integer_zerop (arg0) && !TREE_OVERFLOW (arg0))
2082 if (integer_zerop (arg1) && !TREE_OVERFLOW (arg1))
2085 else if (code == MINUS_EXPR)
2087 if (integer_zerop (arg1) && !TREE_OVERFLOW (arg1))
2090 else if (code == MULT_EXPR)
2092 if (integer_onep (arg0) && !TREE_OVERFLOW (arg0))
2096 /* Handle general case of two integer constants. */
2097 return int_const_binop (code, arg0, arg1, 0);
2100 return fold_build2 (code, type, arg0, arg1);
2103 /* Given two values, either both of sizetype or both of bitsizetype,
2104 compute the difference between the two values. Return the value
2105 in signed type corresponding to the type of the operands. */
2108 size_diffop (tree arg0, tree arg1)
2110 tree type = TREE_TYPE (arg0);
2113 gcc_assert (int_binop_types_match_p (MINUS_EXPR, TREE_TYPE (arg0),
2116 /* If the type is already signed, just do the simple thing. */
2117 if (!TYPE_UNSIGNED (type))
2118 return size_binop (MINUS_EXPR, arg0, arg1);
2120 if (type == sizetype)
2122 else if (type == bitsizetype)
2123 ctype = sbitsizetype;
2125 ctype = signed_type_for (type);
2127 /* If either operand is not a constant, do the conversions to the signed
2128 type and subtract. The hardware will do the right thing with any
2129 overflow in the subtraction. */
2130 if (TREE_CODE (arg0) != INTEGER_CST || TREE_CODE (arg1) != INTEGER_CST)
2131 return size_binop (MINUS_EXPR, fold_convert (ctype, arg0),
2132 fold_convert (ctype, arg1));
2134 /* If ARG0 is larger than ARG1, subtract and return the result in CTYPE.
2135 Otherwise, subtract the other way, convert to CTYPE (we know that can't
2136 overflow) and negate (which can't either). Special-case a result
2137 of zero while we're here. */
2138 if (tree_int_cst_equal (arg0, arg1))
2139 return build_int_cst (ctype, 0);
2140 else if (tree_int_cst_lt (arg1, arg0))
2141 return fold_convert (ctype, size_binop (MINUS_EXPR, arg0, arg1));
2143 return size_binop (MINUS_EXPR, build_int_cst (ctype, 0),
2144 fold_convert (ctype, size_binop (MINUS_EXPR,
2148 /* A subroutine of fold_convert_const handling conversions of an
2149 INTEGER_CST to another integer type. */
2152 fold_convert_const_int_from_int (tree type, const_tree arg1)
2156 /* Given an integer constant, make new constant with new type,
2157 appropriately sign-extended or truncated. */
2158 t = force_fit_type_double (type, TREE_INT_CST_LOW (arg1),
2159 TREE_INT_CST_HIGH (arg1),
2160 /* Don't set the overflow when
2161 converting from a pointer, */
2162 !POINTER_TYPE_P (TREE_TYPE (arg1))
2163 /* or to a sizetype with same signedness
2164 and the precision is unchanged.
2165 ??? sizetype is always sign-extended,
2166 but its signedness depends on the
2167 frontend. Thus we see spurious overflows
2168 here if we do not check this. */
2169 && !((TYPE_PRECISION (TREE_TYPE (arg1))
2170 == TYPE_PRECISION (type))
2171 && (TYPE_UNSIGNED (TREE_TYPE (arg1))
2172 == TYPE_UNSIGNED (type))
2173 && ((TREE_CODE (TREE_TYPE (arg1)) == INTEGER_TYPE
2174 && TYPE_IS_SIZETYPE (TREE_TYPE (arg1)))
2175 || (TREE_CODE (type) == INTEGER_TYPE
2176 && TYPE_IS_SIZETYPE (type)))),
2177 (TREE_INT_CST_HIGH (arg1) < 0
2178 && (TYPE_UNSIGNED (type)
2179 < TYPE_UNSIGNED (TREE_TYPE (arg1))))
2180 | TREE_OVERFLOW (arg1));
2185 /* A subroutine of fold_convert_const handling conversions a REAL_CST
2186 to an integer type. */
2189 fold_convert_const_int_from_real (enum tree_code code, tree type, const_tree arg1)
2194 /* The following code implements the floating point to integer
2195 conversion rules required by the Java Language Specification,
2196 that IEEE NaNs are mapped to zero and values that overflow
2197 the target precision saturate, i.e. values greater than
2198 INT_MAX are mapped to INT_MAX, and values less than INT_MIN
2199 are mapped to INT_MIN. These semantics are allowed by the
2200 C and C++ standards that simply state that the behavior of
2201 FP-to-integer conversion is unspecified upon overflow. */
2203 HOST_WIDE_INT high, low;
2205 REAL_VALUE_TYPE x = TREE_REAL_CST (arg1);
2209 case FIX_TRUNC_EXPR:
2210 real_trunc (&r, VOIDmode, &x);
2217 /* If R is NaN, return zero and show we have an overflow. */
2218 if (REAL_VALUE_ISNAN (r))
2225 /* See if R is less than the lower bound or greater than the
2230 tree lt = TYPE_MIN_VALUE (type);
2231 REAL_VALUE_TYPE l = real_value_from_int_cst (NULL_TREE, lt);
2232 if (REAL_VALUES_LESS (r, l))
2235 high = TREE_INT_CST_HIGH (lt);
2236 low = TREE_INT_CST_LOW (lt);
2242 tree ut = TYPE_MAX_VALUE (type);
2245 REAL_VALUE_TYPE u = real_value_from_int_cst (NULL_TREE, ut);
2246 if (REAL_VALUES_LESS (u, r))
2249 high = TREE_INT_CST_HIGH (ut);
2250 low = TREE_INT_CST_LOW (ut);
2256 REAL_VALUE_TO_INT (&low, &high, r);
2258 t = force_fit_type_double (type, low, high, -1,
2259 overflow | TREE_OVERFLOW (arg1));
2263 /* A subroutine of fold_convert_const handling conversions of a
2264 FIXED_CST to an integer type. */
2267 fold_convert_const_int_from_fixed (tree type, const_tree arg1)
2270 double_int temp, temp_trunc;
2273 /* Right shift FIXED_CST to temp by fbit. */
2274 temp = TREE_FIXED_CST (arg1).data;
2275 mode = TREE_FIXED_CST (arg1).mode;
2276 if (GET_MODE_FBIT (mode) < 2 * HOST_BITS_PER_WIDE_INT)
2278 lshift_double (temp.low, temp.high,
2279 - GET_MODE_FBIT (mode), 2 * HOST_BITS_PER_WIDE_INT,
2280 &temp.low, &temp.high, SIGNED_FIXED_POINT_MODE_P (mode));
2282 /* Left shift temp to temp_trunc by fbit. */
2283 lshift_double (temp.low, temp.high,
2284 GET_MODE_FBIT (mode), 2 * HOST_BITS_PER_WIDE_INT,
2285 &temp_trunc.low, &temp_trunc.high,
2286 SIGNED_FIXED_POINT_MODE_P (mode));
2293 temp_trunc.high = 0;
2296 /* If FIXED_CST is negative, we need to round the value toward 0.
2297 By checking if the fractional bits are not zero to add 1 to temp. */
2298 if (SIGNED_FIXED_POINT_MODE_P (mode) && temp_trunc.high < 0
2299 && !double_int_equal_p (TREE_FIXED_CST (arg1).data, temp_trunc))
2304 temp = double_int_add (temp, one);
2307 /* Given a fixed-point constant, make new constant with new type,
2308 appropriately sign-extended or truncated. */
2309 t = force_fit_type_double (type, temp.low, temp.high, -1,
2311 && (TYPE_UNSIGNED (type)
2312 < TYPE_UNSIGNED (TREE_TYPE (arg1))))
2313 | TREE_OVERFLOW (arg1));
2318 /* A subroutine of fold_convert_const handling conversions a REAL_CST
2319 to another floating point type. */
2322 fold_convert_const_real_from_real (tree type, const_tree arg1)
2324 REAL_VALUE_TYPE value;
2327 real_convert (&value, TYPE_MODE (type), &TREE_REAL_CST (arg1));
2328 t = build_real (type, value);
2330 TREE_OVERFLOW (t) = TREE_OVERFLOW (arg1);
2334 /* A subroutine of fold_convert_const handling conversions a FIXED_CST
2335 to a floating point type. */
2338 fold_convert_const_real_from_fixed (tree type, const_tree arg1)
2340 REAL_VALUE_TYPE value;
2343 real_convert_from_fixed (&value, TYPE_MODE (type), &TREE_FIXED_CST (arg1));
2344 t = build_real (type, value);
2346 TREE_OVERFLOW (t) = TREE_OVERFLOW (arg1);
2350 /* A subroutine of fold_convert_const handling conversions a FIXED_CST
2351 to another fixed-point type. */
2354 fold_convert_const_fixed_from_fixed (tree type, const_tree arg1)
2356 FIXED_VALUE_TYPE value;
2360 overflow_p = fixed_convert (&value, TYPE_MODE (type), &TREE_FIXED_CST (arg1),
2361 TYPE_SATURATING (type));
2362 t = build_fixed (type, value);
2364 /* Propagate overflow flags. */
2365 if (overflow_p | TREE_OVERFLOW (arg1))
2366 TREE_OVERFLOW (t) = 1;
2370 /* A subroutine of fold_convert_const handling conversions an INTEGER_CST
2371 to a fixed-point type. */
2374 fold_convert_const_fixed_from_int (tree type, const_tree arg1)
2376 FIXED_VALUE_TYPE value;
2380 overflow_p = fixed_convert_from_int (&value, TYPE_MODE (type),
2381 TREE_INT_CST (arg1),
2382 TYPE_UNSIGNED (TREE_TYPE (arg1)),
2383 TYPE_SATURATING (type));
2384 t = build_fixed (type, value);
2386 /* Propagate overflow flags. */
2387 if (overflow_p | TREE_OVERFLOW (arg1))
2388 TREE_OVERFLOW (t) = 1;
2392 /* A subroutine of fold_convert_const handling conversions a REAL_CST
2393 to a fixed-point type. */
2396 fold_convert_const_fixed_from_real (tree type, const_tree arg1)
2398 FIXED_VALUE_TYPE value;
2402 overflow_p = fixed_convert_from_real (&value, TYPE_MODE (type),
2403 &TREE_REAL_CST (arg1),
2404 TYPE_SATURATING (type));
2405 t = build_fixed (type, value);
2407 /* Propagate overflow flags. */
2408 if (overflow_p | TREE_OVERFLOW (arg1))
2409 TREE_OVERFLOW (t) = 1;
2413 /* Attempt to fold type conversion operation CODE of expression ARG1 to
2414 type TYPE. If no simplification can be done return NULL_TREE. */
2417 fold_convert_const (enum tree_code code, tree type, tree arg1)
2419 if (TREE_TYPE (arg1) == type)
2422 if (POINTER_TYPE_P (type) || INTEGRAL_TYPE_P (type)
2423 || TREE_CODE (type) == OFFSET_TYPE)
2425 if (TREE_CODE (arg1) == INTEGER_CST)
2426 return fold_convert_const_int_from_int (type, arg1);
2427 else if (TREE_CODE (arg1) == REAL_CST)
2428 return fold_convert_const_int_from_real (code, type, arg1);
2429 else if (TREE_CODE (arg1) == FIXED_CST)
2430 return fold_convert_const_int_from_fixed (type, arg1);
2432 else if (TREE_CODE (type) == REAL_TYPE)
2434 if (TREE_CODE (arg1) == INTEGER_CST)
2435 return build_real_from_int_cst (type, arg1);
2436 else if (TREE_CODE (arg1) == REAL_CST)
2437 return fold_convert_const_real_from_real (type, arg1);
2438 else if (TREE_CODE (arg1) == FIXED_CST)
2439 return fold_convert_const_real_from_fixed (type, arg1);
2441 else if (TREE_CODE (type) == FIXED_POINT_TYPE)
2443 if (TREE_CODE (arg1) == FIXED_CST)
2444 return fold_convert_const_fixed_from_fixed (type, arg1);
2445 else if (TREE_CODE (arg1) == INTEGER_CST)
2446 return fold_convert_const_fixed_from_int (type, arg1);
2447 else if (TREE_CODE (arg1) == REAL_CST)
2448 return fold_convert_const_fixed_from_real (type, arg1);
2453 /* Construct a vector of zero elements of vector type TYPE. */
2456 build_zero_vector (tree type)
2461 elem = fold_convert_const (NOP_EXPR, TREE_TYPE (type), integer_zero_node);
2462 units = TYPE_VECTOR_SUBPARTS (type);
2465 for (i = 0; i < units; i++)
2466 list = tree_cons (NULL_TREE, elem, list);
2467 return build_vector (type, list);
2470 /* Returns true, if ARG is convertible to TYPE using a NOP_EXPR. */
2473 fold_convertible_p (const_tree type, const_tree arg)
2475 tree orig = TREE_TYPE (arg);
2480 if (TREE_CODE (arg) == ERROR_MARK
2481 || TREE_CODE (type) == ERROR_MARK
2482 || TREE_CODE (orig) == ERROR_MARK)
2485 if (TYPE_MAIN_VARIANT (type) == TYPE_MAIN_VARIANT (orig))
2488 switch (TREE_CODE (type))
2490 case INTEGER_TYPE: case ENUMERAL_TYPE: case BOOLEAN_TYPE:
2491 case POINTER_TYPE: case REFERENCE_TYPE:
2493 if (INTEGRAL_TYPE_P (orig) || POINTER_TYPE_P (orig)
2494 || TREE_CODE (orig) == OFFSET_TYPE)
2496 return (TREE_CODE (orig) == VECTOR_TYPE
2497 && tree_int_cst_equal (TYPE_SIZE (type), TYPE_SIZE (orig)));
2500 case FIXED_POINT_TYPE:
2504 return TREE_CODE (type) == TREE_CODE (orig);
2511 /* Convert expression ARG to type TYPE. Used by the middle-end for
2512 simple conversions in preference to calling the front-end's convert. */
2515 fold_convert (tree type, tree arg)
2517 tree orig = TREE_TYPE (arg);
2523 if (TREE_CODE (arg) == ERROR_MARK
2524 || TREE_CODE (type) == ERROR_MARK
2525 || TREE_CODE (orig) == ERROR_MARK)
2526 return error_mark_node;
2528 if (TYPE_MAIN_VARIANT (type) == TYPE_MAIN_VARIANT (orig))
2529 return fold_build1 (NOP_EXPR, type, arg);
2531 switch (TREE_CODE (type))
2533 case INTEGER_TYPE: case ENUMERAL_TYPE: case BOOLEAN_TYPE:
2534 case POINTER_TYPE: case REFERENCE_TYPE:
2536 if (TREE_CODE (arg) == INTEGER_CST)
2538 tem = fold_convert_const (NOP_EXPR, type, arg);
2539 if (tem != NULL_TREE)
2542 if (INTEGRAL_TYPE_P (orig) || POINTER_TYPE_P (orig)
2543 || TREE_CODE (orig) == OFFSET_TYPE)
2544 return fold_build1 (NOP_EXPR, type, arg);
2545 if (TREE_CODE (orig) == COMPLEX_TYPE)
2547 tem = fold_build1 (REALPART_EXPR, TREE_TYPE (orig), arg);
2548 return fold_convert (type, tem);
2550 gcc_assert (TREE_CODE (orig) == VECTOR_TYPE
2551 && tree_int_cst_equal (TYPE_SIZE (type), TYPE_SIZE (orig)));
2552 return fold_build1 (NOP_EXPR, type, arg);
2555 if (TREE_CODE (arg) == INTEGER_CST)
2557 tem = fold_convert_const (FLOAT_EXPR, type, arg);
2558 if (tem != NULL_TREE)
2561 else if (TREE_CODE (arg) == REAL_CST)
2563 tem = fold_convert_const (NOP_EXPR, type, arg);
2564 if (tem != NULL_TREE)
2567 else if (TREE_CODE (arg) == FIXED_CST)
2569 tem = fold_convert_const (FIXED_CONVERT_EXPR, type, arg);
2570 if (tem != NULL_TREE)
2574 switch (TREE_CODE (orig))
2577 case BOOLEAN_TYPE: case ENUMERAL_TYPE:
2578 case POINTER_TYPE: case REFERENCE_TYPE:
2579 return fold_build1 (FLOAT_EXPR, type, arg);
2582 return fold_build1 (NOP_EXPR, type, arg);
2584 case FIXED_POINT_TYPE:
2585 return fold_build1 (FIXED_CONVERT_EXPR, type, arg);
2588 tem = fold_build1 (REALPART_EXPR, TREE_TYPE (orig), arg);
2589 return fold_convert (type, tem);
2595 case FIXED_POINT_TYPE:
2596 if (TREE_CODE (arg) == FIXED_CST || TREE_CODE (arg) == INTEGER_CST
2597 || TREE_CODE (arg) == REAL_CST)
2599 tem = fold_convert_const (FIXED_CONVERT_EXPR, type, arg);
2600 if (tem != NULL_TREE)
2604 switch (TREE_CODE (orig))
2606 case FIXED_POINT_TYPE:
2611 return fold_build1 (FIXED_CONVERT_EXPR, type, arg);
2614 tem = fold_build1 (REALPART_EXPR, TREE_TYPE (orig), arg);
2615 return fold_convert (type, tem);
2622 switch (TREE_CODE (orig))
2625 case BOOLEAN_TYPE: case ENUMERAL_TYPE:
2626 case POINTER_TYPE: case REFERENCE_TYPE:
2628 case FIXED_POINT_TYPE:
2629 return build2 (COMPLEX_EXPR, type,
2630 fold_convert (TREE_TYPE (type), arg),
2631 fold_convert (TREE_TYPE (type), integer_zero_node));
2636 if (TREE_CODE (arg) == COMPLEX_EXPR)
2638 rpart = fold_convert (TREE_TYPE (type), TREE_OPERAND (arg, 0));
2639 ipart = fold_convert (TREE_TYPE (type), TREE_OPERAND (arg, 1));
2640 return fold_build2 (COMPLEX_EXPR, type, rpart, ipart);
2643 arg = save_expr (arg);
2644 rpart = fold_build1 (REALPART_EXPR, TREE_TYPE (orig), arg);
2645 ipart = fold_build1 (IMAGPART_EXPR, TREE_TYPE (orig), arg);
2646 rpart = fold_convert (TREE_TYPE (type), rpart);
2647 ipart = fold_convert (TREE_TYPE (type), ipart);
2648 return fold_build2 (COMPLEX_EXPR, type, rpart, ipart);
2656 if (integer_zerop (arg))
2657 return build_zero_vector (type);
2658 gcc_assert (tree_int_cst_equal (TYPE_SIZE (type), TYPE_SIZE (orig)));
2659 gcc_assert (INTEGRAL_TYPE_P (orig) || POINTER_TYPE_P (orig)
2660 || TREE_CODE (orig) == VECTOR_TYPE);
2661 return fold_build1 (VIEW_CONVERT_EXPR, type, arg);
2664 tem = fold_ignored_result (arg);
2665 if (TREE_CODE (tem) == MODIFY_EXPR)
2667 return fold_build1 (NOP_EXPR, type, tem);
2674 /* Return false if expr can be assumed not to be an lvalue, true
2678 maybe_lvalue_p (const_tree x)
2680 /* We only need to wrap lvalue tree codes. */
2681 switch (TREE_CODE (x))
2692 case ALIGN_INDIRECT_REF:
2693 case MISALIGNED_INDIRECT_REF:
2695 case ARRAY_RANGE_REF:
2701 case PREINCREMENT_EXPR:
2702 case PREDECREMENT_EXPR:
2704 case TRY_CATCH_EXPR:
2705 case WITH_CLEANUP_EXPR:
2716 /* Assume the worst for front-end tree codes. */
2717 if ((int)TREE_CODE (x) >= NUM_TREE_CODES)
2725 /* Return an expr equal to X but certainly not valid as an lvalue. */
2730 /* While we are in GIMPLE, NON_LVALUE_EXPR doesn't mean anything to
2735 if (! maybe_lvalue_p (x))
2737 return build1 (NON_LVALUE_EXPR, TREE_TYPE (x), x);
2740 /* Nonzero means lvalues are limited to those valid in pedantic ANSI C.
2741 Zero means allow extended lvalues. */
2743 int pedantic_lvalues;
2745 /* When pedantic, return an expr equal to X but certainly not valid as a
2746 pedantic lvalue. Otherwise, return X. */
2749 pedantic_non_lvalue (tree x)
2751 if (pedantic_lvalues)
2752 return non_lvalue (x);
2757 /* Given a tree comparison code, return the code that is the logical inverse
2758 of the given code. It is not safe to do this for floating-point
2759 comparisons, except for NE_EXPR and EQ_EXPR, so we receive a machine mode
2760 as well: if reversing the comparison is unsafe, return ERROR_MARK. */
2763 invert_tree_comparison (enum tree_code code, bool honor_nans)
2765 if (honor_nans && flag_trapping_math)
2775 return honor_nans ? UNLE_EXPR : LE_EXPR;
2777 return honor_nans ? UNLT_EXPR : LT_EXPR;
2779 return honor_nans ? UNGE_EXPR : GE_EXPR;
2781 return honor_nans ? UNGT_EXPR : GT_EXPR;
2795 return UNORDERED_EXPR;
2796 case UNORDERED_EXPR:
2797 return ORDERED_EXPR;
2803 /* Similar, but return the comparison that results if the operands are
2804 swapped. This is safe for floating-point. */
2807 swap_tree_comparison (enum tree_code code)
2814 case UNORDERED_EXPR:
2840 /* Convert a comparison tree code from an enum tree_code representation
2841 into a compcode bit-based encoding. This function is the inverse of
2842 compcode_to_comparison. */
2844 static enum comparison_code
2845 comparison_to_compcode (enum tree_code code)
2862 return COMPCODE_ORD;
2863 case UNORDERED_EXPR:
2864 return COMPCODE_UNORD;
2866 return COMPCODE_UNLT;
2868 return COMPCODE_UNEQ;
2870 return COMPCODE_UNLE;
2872 return COMPCODE_UNGT;
2874 return COMPCODE_LTGT;
2876 return COMPCODE_UNGE;
2882 /* Convert a compcode bit-based encoding of a comparison operator back
2883 to GCC's enum tree_code representation. This function is the
2884 inverse of comparison_to_compcode. */
2886 static enum tree_code
2887 compcode_to_comparison (enum comparison_code code)
2904 return ORDERED_EXPR;
2905 case COMPCODE_UNORD:
2906 return UNORDERED_EXPR;
2924 /* Return a tree for the comparison which is the combination of
2925 doing the AND or OR (depending on CODE) of the two operations LCODE
2926 and RCODE on the identical operands LL_ARG and LR_ARG. Take into account
2927 the possibility of trapping if the mode has NaNs, and return NULL_TREE
2928 if this makes the transformation invalid. */
2931 combine_comparisons (enum tree_code code, enum tree_code lcode,
2932 enum tree_code rcode, tree truth_type,
2933 tree ll_arg, tree lr_arg)
2935 bool honor_nans = HONOR_NANS (TYPE_MODE (TREE_TYPE (ll_arg)));
2936 enum comparison_code lcompcode = comparison_to_compcode (lcode);
2937 enum comparison_code rcompcode = comparison_to_compcode (rcode);
2938 enum comparison_code compcode;
2942 case TRUTH_AND_EXPR: case TRUTH_ANDIF_EXPR:
2943 compcode = lcompcode & rcompcode;
2946 case TRUTH_OR_EXPR: case TRUTH_ORIF_EXPR:
2947 compcode = lcompcode | rcompcode;
2956 /* Eliminate unordered comparisons, as well as LTGT and ORD
2957 which are not used unless the mode has NaNs. */
2958 compcode &= ~COMPCODE_UNORD;
2959 if (compcode == COMPCODE_LTGT)
2960 compcode = COMPCODE_NE;
2961 else if (compcode == COMPCODE_ORD)
2962 compcode = COMPCODE_TRUE;
2964 else if (flag_trapping_math)
2966 /* Check that the original operation and the optimized ones will trap
2967 under the same condition. */
2968 bool ltrap = (lcompcode & COMPCODE_UNORD) == 0
2969 && (lcompcode != COMPCODE_EQ)
2970 && (lcompcode != COMPCODE_ORD);
2971 bool rtrap = (rcompcode & COMPCODE_UNORD) == 0
2972 && (rcompcode != COMPCODE_EQ)
2973 && (rcompcode != COMPCODE_ORD);
2974 bool trap = (compcode & COMPCODE_UNORD) == 0
2975 && (compcode != COMPCODE_EQ)
2976 && (compcode != COMPCODE_ORD);
2978 /* In a short-circuited boolean expression the LHS might be
2979 such that the RHS, if evaluated, will never trap. For
2980 example, in ORD (x, y) && (x < y), we evaluate the RHS only
2981 if neither x nor y is NaN. (This is a mixed blessing: for
2982 example, the expression above will never trap, hence
2983 optimizing it to x < y would be invalid). */
2984 if ((code == TRUTH_ORIF_EXPR && (lcompcode & COMPCODE_UNORD))
2985 || (code == TRUTH_ANDIF_EXPR && !(lcompcode & COMPCODE_UNORD)))
2988 /* If the comparison was short-circuited, and only the RHS
2989 trapped, we may now generate a spurious trap. */
2991 && (code == TRUTH_ANDIF_EXPR || code == TRUTH_ORIF_EXPR))
2994 /* If we changed the conditions that cause a trap, we lose. */
2995 if ((ltrap || rtrap) != trap)
2999 if (compcode == COMPCODE_TRUE)
3000 return constant_boolean_node (true, truth_type);
3001 else if (compcode == COMPCODE_FALSE)
3002 return constant_boolean_node (false, truth_type);
3004 return fold_build2 (compcode_to_comparison (compcode),
3005 truth_type, ll_arg, lr_arg);
3008 /* Return nonzero if two operands (typically of the same tree node)
3009 are necessarily equal. If either argument has side-effects this
3010 function returns zero. FLAGS modifies behavior as follows:
3012 If OEP_ONLY_CONST is set, only return nonzero for constants.
3013 This function tests whether the operands are indistinguishable;
3014 it does not test whether they are equal using C's == operation.
3015 The distinction is important for IEEE floating point, because
3016 (1) -0.0 and 0.0 are distinguishable, but -0.0==0.0, and
3017 (2) two NaNs may be indistinguishable, but NaN!=NaN.
3019 If OEP_ONLY_CONST is unset, a VAR_DECL is considered equal to itself
3020 even though it may hold multiple values during a function.
3021 This is because a GCC tree node guarantees that nothing else is
3022 executed between the evaluation of its "operands" (which may often
3023 be evaluated in arbitrary order). Hence if the operands themselves
3024 don't side-effect, the VAR_DECLs, PARM_DECLs etc... must hold the
3025 same value in each operand/subexpression. Hence leaving OEP_ONLY_CONST
3026 unset means assuming isochronic (or instantaneous) tree equivalence.
3027 Unless comparing arbitrary expression trees, such as from different
3028 statements, this flag can usually be left unset.
3030 If OEP_PURE_SAME is set, then pure functions with identical arguments
3031 are considered the same. It is used when the caller has other ways
3032 to ensure that global memory is unchanged in between. */
3035 operand_equal_p (const_tree arg0, const_tree arg1, unsigned int flags)
3037 /* If either is ERROR_MARK, they aren't equal. */
3038 if (TREE_CODE (arg0) == ERROR_MARK || TREE_CODE (arg1) == ERROR_MARK)
3041 /* Check equality of integer constants before bailing out due to
3042 precision differences. */
3043 if (TREE_CODE (arg0) == INTEGER_CST && TREE_CODE (arg1) == INTEGER_CST)
3044 return tree_int_cst_equal (arg0, arg1);
3046 /* If both types don't have the same signedness, then we can't consider
3047 them equal. We must check this before the STRIP_NOPS calls
3048 because they may change the signedness of the arguments. As pointers
3049 strictly don't have a signedness, require either two pointers or
3050 two non-pointers as well. */
3051 if (TYPE_UNSIGNED (TREE_TYPE (arg0)) != TYPE_UNSIGNED (TREE_TYPE (arg1))
3052 || POINTER_TYPE_P (TREE_TYPE (arg0)) != POINTER_TYPE_P (TREE_TYPE (arg1)))
3055 /* If both types don't have the same precision, then it is not safe
3057 if (TYPE_PRECISION (TREE_TYPE (arg0)) != TYPE_PRECISION (TREE_TYPE (arg1)))
3063 /* In case both args are comparisons but with different comparison
3064 code, try to swap the comparison operands of one arg to produce
3065 a match and compare that variant. */
3066 if (TREE_CODE (arg0) != TREE_CODE (arg1)
3067 && COMPARISON_CLASS_P (arg0)
3068 && COMPARISON_CLASS_P (arg1))
3070 enum tree_code swap_code = swap_tree_comparison (TREE_CODE (arg1));
3072 if (TREE_CODE (arg0) == swap_code)
3073 return operand_equal_p (TREE_OPERAND (arg0, 0),
3074 TREE_OPERAND (arg1, 1), flags)
3075 && operand_equal_p (TREE_OPERAND (arg0, 1),
3076 TREE_OPERAND (arg1, 0), flags);
3079 if (TREE_CODE (arg0) != TREE_CODE (arg1)
3080 /* This is needed for conversions and for COMPONENT_REF.
3081 Might as well play it safe and always test this. */
3082 || TREE_CODE (TREE_TYPE (arg0)) == ERROR_MARK
3083 || TREE_CODE (TREE_TYPE (arg1)) == ERROR_MARK
3084 || TYPE_MODE (TREE_TYPE (arg0)) != TYPE_MODE (TREE_TYPE (arg1)))
3087 /* If ARG0 and ARG1 are the same SAVE_EXPR, they are necessarily equal.
3088 We don't care about side effects in that case because the SAVE_EXPR
3089 takes care of that for us. In all other cases, two expressions are
3090 equal if they have no side effects. If we have two identical
3091 expressions with side effects that should be treated the same due
3092 to the only side effects being identical SAVE_EXPR's, that will
3093 be detected in the recursive calls below. */
3094 if (arg0 == arg1 && ! (flags & OEP_ONLY_CONST)
3095 && (TREE_CODE (arg0) == SAVE_EXPR
3096 || (! TREE_SIDE_EFFECTS (arg0) && ! TREE_SIDE_EFFECTS (arg1))))
3099 /* Next handle constant cases, those for which we can return 1 even
3100 if ONLY_CONST is set. */
3101 if (TREE_CONSTANT (arg0) && TREE_CONSTANT (arg1))
3102 switch (TREE_CODE (arg0))
3105 return tree_int_cst_equal (arg0, arg1);
3108 return FIXED_VALUES_IDENTICAL (TREE_FIXED_CST (arg0),
3109 TREE_FIXED_CST (arg1));
3112 if (REAL_VALUES_IDENTICAL (TREE_REAL_CST (arg0),
3113 TREE_REAL_CST (arg1)))
3117 if (!HONOR_SIGNED_ZEROS (TYPE_MODE (TREE_TYPE (arg0))))
3119 /* If we do not distinguish between signed and unsigned zero,
3120 consider them equal. */
3121 if (real_zerop (arg0) && real_zerop (arg1))
3130 v1 = TREE_VECTOR_CST_ELTS (arg0);
3131 v2 = TREE_VECTOR_CST_ELTS (arg1);
3134 if (!operand_equal_p (TREE_VALUE (v1), TREE_VALUE (v2),
3137 v1 = TREE_CHAIN (v1);
3138 v2 = TREE_CHAIN (v2);
3145 return (operand_equal_p (TREE_REALPART (arg0), TREE_REALPART (arg1),
3147 && operand_equal_p (TREE_IMAGPART (arg0), TREE_IMAGPART (arg1),
3151 return (TREE_STRING_LENGTH (arg0) == TREE_STRING_LENGTH (arg1)
3152 && ! memcmp (TREE_STRING_POINTER (arg0),
3153 TREE_STRING_POINTER (arg1),
3154 TREE_STRING_LENGTH (arg0)));
3157 return operand_equal_p (TREE_OPERAND (arg0, 0), TREE_OPERAND (arg1, 0),
3163 if (flags & OEP_ONLY_CONST)
3166 /* Define macros to test an operand from arg0 and arg1 for equality and a
3167 variant that allows null and views null as being different from any
3168 non-null value. In the latter case, if either is null, the both
3169 must be; otherwise, do the normal comparison. */
3170 #define OP_SAME(N) operand_equal_p (TREE_OPERAND (arg0, N), \
3171 TREE_OPERAND (arg1, N), flags)
3173 #define OP_SAME_WITH_NULL(N) \
3174 ((!TREE_OPERAND (arg0, N) || !TREE_OPERAND (arg1, N)) \
3175 ? TREE_OPERAND (arg0, N) == TREE_OPERAND (arg1, N) : OP_SAME (N))
3177 switch (TREE_CODE_CLASS (TREE_CODE (arg0)))
3180 /* Two conversions are equal only if signedness and modes match. */
3181 switch (TREE_CODE (arg0))
3184 case FIX_TRUNC_EXPR:
3185 if (TYPE_UNSIGNED (TREE_TYPE (arg0))
3186 != TYPE_UNSIGNED (TREE_TYPE (arg1)))
3196 case tcc_comparison:
3198 if (OP_SAME (0) && OP_SAME (1))
3201 /* For commutative ops, allow the other order. */
3202 return (commutative_tree_code (TREE_CODE (arg0))
3203 && operand_equal_p (TREE_OPERAND (arg0, 0),
3204 TREE_OPERAND (arg1, 1), flags)
3205 && operand_equal_p (TREE_OPERAND (arg0, 1),
3206 TREE_OPERAND (arg1, 0), flags));
3209 /* If either of the pointer (or reference) expressions we are
3210 dereferencing contain a side effect, these cannot be equal. */
3211 if (TREE_SIDE_EFFECTS (arg0)
3212 || TREE_SIDE_EFFECTS (arg1))
3215 switch (TREE_CODE (arg0))
3218 case ALIGN_INDIRECT_REF:
3219 case MISALIGNED_INDIRECT_REF:
3225 case ARRAY_RANGE_REF:
3226 /* Operands 2 and 3 may be null.
3227 Compare the array index by value if it is constant first as we
3228 may have different types but same value here. */
3230 && (tree_int_cst_equal (TREE_OPERAND (arg0, 1),
3231 TREE_OPERAND (arg1, 1))
3233 && OP_SAME_WITH_NULL (2)
3234 && OP_SAME_WITH_NULL (3));
3237 /* Handle operand 2 the same as for ARRAY_REF. Operand 0
3238 may be NULL when we're called to compare MEM_EXPRs. */
3239 return OP_SAME_WITH_NULL (0)
3241 && OP_SAME_WITH_NULL (2);
3244 return OP_SAME (0) && OP_SAME (1) && OP_SAME (2);
3250 case tcc_expression:
3251 switch (TREE_CODE (arg0))
3254 case TRUTH_NOT_EXPR:
3257 case TRUTH_ANDIF_EXPR:
3258 case TRUTH_ORIF_EXPR:
3259 return OP_SAME (0) && OP_SAME (1);
3261 case TRUTH_AND_EXPR:
3263 case TRUTH_XOR_EXPR:
3264 if (OP_SAME (0) && OP_SAME (1))
3267 /* Otherwise take into account this is a commutative operation. */
3268 return (operand_equal_p (TREE_OPERAND (arg0, 0),
3269 TREE_OPERAND (arg1, 1), flags)
3270 && operand_equal_p (TREE_OPERAND (arg0, 1),
3271 TREE_OPERAND (arg1, 0), flags));
3274 return OP_SAME (0) && OP_SAME (1) && OP_SAME (2);
3281 switch (TREE_CODE (arg0))
3284 /* If the CALL_EXPRs call different functions, then they
3285 clearly can not be equal. */
3286 if (! operand_equal_p (CALL_EXPR_FN (arg0), CALL_EXPR_FN (arg1),
3291 unsigned int cef = call_expr_flags (arg0);
3292 if (flags & OEP_PURE_SAME)
3293 cef &= ECF_CONST | ECF_PURE;
3300 /* Now see if all the arguments are the same. */
3302 const_call_expr_arg_iterator iter0, iter1;
3304 for (a0 = first_const_call_expr_arg (arg0, &iter0),
3305 a1 = first_const_call_expr_arg (arg1, &iter1);
3307 a0 = next_const_call_expr_arg (&iter0),
3308 a1 = next_const_call_expr_arg (&iter1))
3309 if (! operand_equal_p (a0, a1, flags))
3312 /* If we get here and both argument lists are exhausted
3313 then the CALL_EXPRs are equal. */
3314 return ! (a0 || a1);
3320 case tcc_declaration:
3321 /* Consider __builtin_sqrt equal to sqrt. */
3322 return (TREE_CODE (arg0) == FUNCTION_DECL
3323 && DECL_BUILT_IN (arg0) && DECL_BUILT_IN (arg1)
3324 && DECL_BUILT_IN_CLASS (arg0) == DECL_BUILT_IN_CLASS (arg1)
3325 && DECL_FUNCTION_CODE (arg0) == DECL_FUNCTION_CODE (arg1));
3332 #undef OP_SAME_WITH_NULL
3335 /* Similar to operand_equal_p, but see if ARG0 might have been made by
3336 shorten_compare from ARG1 when ARG1 was being compared with OTHER.
3338 When in doubt, return 0. */
3341 operand_equal_for_comparison_p (tree arg0, tree arg1, tree other)
3343 int unsignedp1, unsignedpo;
3344 tree primarg0, primarg1, primother;
3345 unsigned int correct_width;
3347 if (operand_equal_p (arg0, arg1, 0))
3350 if (! INTEGRAL_TYPE_P (TREE_TYPE (arg0))
3351 || ! INTEGRAL_TYPE_P (TREE_TYPE (arg1)))
3354 /* Discard any conversions that don't change the modes of ARG0 and ARG1
3355 and see if the inner values are the same. This removes any
3356 signedness comparison, which doesn't matter here. */
3357 primarg0 = arg0, primarg1 = arg1;
3358 STRIP_NOPS (primarg0);
3359 STRIP_NOPS (primarg1);
3360 if (operand_equal_p (primarg0, primarg1, 0))
3363 /* Duplicate what shorten_compare does to ARG1 and see if that gives the
3364 actual comparison operand, ARG0.
3366 First throw away any conversions to wider types
3367 already present in the operands. */
3369 primarg1 = get_narrower (arg1, &unsignedp1);
3370 primother = get_narrower (other, &unsignedpo);
3372 correct_width = TYPE_PRECISION (TREE_TYPE (arg1));
3373 if (unsignedp1 == unsignedpo
3374 && TYPE_PRECISION (TREE_TYPE (primarg1)) < correct_width
3375 && TYPE_PRECISION (TREE_TYPE (primother)) < correct_width)
3377 tree type = TREE_TYPE (arg0);
3379 /* Make sure shorter operand is extended the right way
3380 to match the longer operand. */
3381 primarg1 = fold_convert (signed_or_unsigned_type_for
3382 (unsignedp1, TREE_TYPE (primarg1)), primarg1);
3384 if (operand_equal_p (arg0, fold_convert (type, primarg1), 0))
3391 /* See if ARG is an expression that is either a comparison or is performing
3392 arithmetic on comparisons. The comparisons must only be comparing
3393 two different values, which will be stored in *CVAL1 and *CVAL2; if
3394 they are nonzero it means that some operands have already been found.
3395 No variables may be used anywhere else in the expression except in the
3396 comparisons. If SAVE_P is true it means we removed a SAVE_EXPR around
3397 the expression and save_expr needs to be called with CVAL1 and CVAL2.
3399 If this is true, return 1. Otherwise, return zero. */
3402 twoval_comparison_p (tree arg, tree *cval1, tree *cval2, int *save_p)
3404 enum tree_code code = TREE_CODE (arg);
3405 enum tree_code_class tclass = TREE_CODE_CLASS (code);
3407 /* We can handle some of the tcc_expression cases here. */
3408 if (tclass == tcc_expression && code == TRUTH_NOT_EXPR)
3410 else if (tclass == tcc_expression
3411 && (code == TRUTH_ANDIF_EXPR || code == TRUTH_ORIF_EXPR
3412 || code == COMPOUND_EXPR))
3413 tclass = tcc_binary;
3415 else if (tclass == tcc_expression && code == SAVE_EXPR
3416 && ! TREE_SIDE_EFFECTS (TREE_OPERAND (arg, 0)))
3418 /* If we've already found a CVAL1 or CVAL2, this expression is
3419 two complex to handle. */
3420 if (*cval1 || *cval2)
3430 return twoval_comparison_p (TREE_OPERAND (arg, 0), cval1, cval2, save_p);
3433 return (twoval_comparison_p (TREE_OPERAND (arg, 0), cval1, cval2, save_p)
3434 && twoval_comparison_p (TREE_OPERAND (arg, 1),
3435 cval1, cval2, save_p));
3440 case tcc_expression:
3441 if (code == COND_EXPR)
3442 return (twoval_comparison_p (TREE_OPERAND (arg, 0),
3443 cval1, cval2, save_p)
3444 && twoval_comparison_p (TREE_OPERAND (arg, 1),
3445 cval1, cval2, save_p)
3446 && twoval_comparison_p (TREE_OPERAND (arg, 2),
3447 cval1, cval2, save_p));
3450 case tcc_comparison:
3451 /* First see if we can handle the first operand, then the second. For
3452 the second operand, we know *CVAL1 can't be zero. It must be that
3453 one side of the comparison is each of the values; test for the
3454 case where this isn't true by failing if the two operands
3457 if (operand_equal_p (TREE_OPERAND (arg, 0),
3458 TREE_OPERAND (arg, 1), 0))
3462 *cval1 = TREE_OPERAND (arg, 0);
3463 else if (operand_equal_p (*cval1, TREE_OPERAND (arg, 0), 0))
3465 else if (*cval2 == 0)
3466 *cval2 = TREE_OPERAND (arg, 0);
3467 else if (operand_equal_p (*cval2, TREE_OPERAND (arg, 0), 0))
3472 if (operand_equal_p (*cval1, TREE_OPERAND (arg, 1), 0))
3474 else if (*cval2 == 0)
3475 *cval2 = TREE_OPERAND (arg, 1);
3476 else if (operand_equal_p (*cval2, TREE_OPERAND (arg, 1), 0))
3488 /* ARG is a tree that is known to contain just arithmetic operations and
3489 comparisons. Evaluate the operations in the tree substituting NEW0 for
3490 any occurrence of OLD0 as an operand of a comparison and likewise for
3494 eval_subst (tree arg, tree old0, tree new0, tree old1, tree new1)
3496 tree type = TREE_TYPE (arg);
3497 enum tree_code code = TREE_CODE (arg);
3498 enum tree_code_class tclass = TREE_CODE_CLASS (code);
3500 /* We can handle some of the tcc_expression cases here. */
3501 if (tclass == tcc_expression && code == TRUTH_NOT_EXPR)
3503 else if (tclass == tcc_expression
3504 && (code == TRUTH_ANDIF_EXPR || code == TRUTH_ORIF_EXPR))
3505 tclass = tcc_binary;
3510 return fold_build1 (code, type,
3511 eval_subst (TREE_OPERAND (arg, 0),
3512 old0, new0, old1, new1));
3515 return fold_build2 (code, type,
3516 eval_subst (TREE_OPERAND (arg, 0),
3517 old0, new0, old1, new1),
3518 eval_subst (TREE_OPERAND (arg, 1),
3519 old0, new0, old1, new1));
3521 case tcc_expression:
3525 return eval_subst (TREE_OPERAND (arg, 0), old0, new0, old1, new1);
3528 return eval_subst (TREE_OPERAND (arg, 1), old0, new0, old1, new1);
3531 return fold_build3 (code, type,
3532 eval_subst (TREE_OPERAND (arg, 0),
3533 old0, new0, old1, new1),
3534 eval_subst (TREE_OPERAND (arg, 1),
3535 old0, new0, old1, new1),
3536 eval_subst (TREE_OPERAND (arg, 2),
3537 old0, new0, old1, new1));
3541 /* Fall through - ??? */
3543 case tcc_comparison:
3545 tree arg0 = TREE_OPERAND (arg, 0);
3546 tree arg1 = TREE_OPERAND (arg, 1);
3548 /* We need to check both for exact equality and tree equality. The
3549 former will be true if the operand has a side-effect. In that
3550 case, we know the operand occurred exactly once. */
3552 if (arg0 == old0 || operand_equal_p (arg0, old0, 0))
3554 else if (arg0 == old1 || operand_equal_p (arg0, old1, 0))
3557 if (arg1 == old0 || operand_equal_p (arg1, old0, 0))
3559 else if (arg1 == old1 || operand_equal_p (arg1, old1, 0))
3562 return fold_build2 (code, type, arg0, arg1);
3570 /* Return a tree for the case when the result of an expression is RESULT
3571 converted to TYPE and OMITTED was previously an operand of the expression
3572 but is now not needed (e.g., we folded OMITTED * 0).
3574 If OMITTED has side effects, we must evaluate it. Otherwise, just do
3575 the conversion of RESULT to TYPE. */
3578 omit_one_operand (tree type, tree result, tree omitted)
3580 tree t = fold_convert (type, result);
3582 /* If the resulting operand is an empty statement, just return the omitted
3583 statement casted to void. */
3584 if (IS_EMPTY_STMT (t) && TREE_SIDE_EFFECTS (omitted))
3585 return build1 (NOP_EXPR, void_type_node, fold_ignored_result (omitted));
3587 if (TREE_SIDE_EFFECTS (omitted))
3588 return build2 (COMPOUND_EXPR, type, fold_ignored_result (omitted), t);
3590 return non_lvalue (t);
3593 /* Similar, but call pedantic_non_lvalue instead of non_lvalue. */
3596 pedantic_omit_one_operand (tree type, tree result, tree omitted)
3598 tree t = fold_convert (type, result);
3600 /* If the resulting operand is an empty statement, just return the omitted
3601 statement casted to void. */
3602 if (IS_EMPTY_STMT (t) && TREE_SIDE_EFFECTS (omitted))
3603 return build1 (NOP_EXPR, void_type_node, fold_ignored_result (omitted));
3605 if (TREE_SIDE_EFFECTS (omitted))
3606 return build2 (COMPOUND_EXPR, type, fold_ignored_result (omitted), t);
3608 return pedantic_non_lvalue (t);
3611 /* Return a tree for the case when the result of an expression is RESULT
3612 converted to TYPE and OMITTED1 and OMITTED2 were previously operands
3613 of the expression but are now not needed.
3615 If OMITTED1 or OMITTED2 has side effects, they must be evaluated.
3616 If both OMITTED1 and OMITTED2 have side effects, OMITTED1 is
3617 evaluated before OMITTED2. Otherwise, if neither has side effects,
3618 just do the conversion of RESULT to TYPE. */
3621 omit_two_operands (tree type, tree result, tree omitted1, tree omitted2)
3623 tree t = fold_convert (type, result);
3625 if (TREE_SIDE_EFFECTS (omitted2))
3626 t = build2 (COMPOUND_EXPR, type, omitted2, t);
3627 if (TREE_SIDE_EFFECTS (omitted1))
3628 t = build2 (COMPOUND_EXPR, type, omitted1, t);
3630 return TREE_CODE (t) != COMPOUND_EXPR ? non_lvalue (t) : t;
3634 /* Return a simplified tree node for the truth-negation of ARG. This
3635 never alters ARG itself. We assume that ARG is an operation that
3636 returns a truth value (0 or 1).
3638 FIXME: one would think we would fold the result, but it causes
3639 problems with the dominator optimizer. */
3642 fold_truth_not_expr (tree arg)
3644 tree type = TREE_TYPE (arg);
3645 enum tree_code code = TREE_CODE (arg);
3647 /* If this is a comparison, we can simply invert it, except for
3648 floating-point non-equality comparisons, in which case we just
3649 enclose a TRUTH_NOT_EXPR around what we have. */
3651 if (TREE_CODE_CLASS (code) == tcc_comparison)
3653 tree op_type = TREE_TYPE (TREE_OPERAND (arg, 0));
3654 if (FLOAT_TYPE_P (op_type)
3655 && flag_trapping_math
3656 && code != ORDERED_EXPR && code != UNORDERED_EXPR
3657 && code != NE_EXPR && code != EQ_EXPR)
3661 code = invert_tree_comparison (code,
3662 HONOR_NANS (TYPE_MODE (op_type)));
3663 if (code == ERROR_MARK)
3666 return build2 (code, type,
3667 TREE_OPERAND (arg, 0), TREE_OPERAND (arg, 1));
3674 return constant_boolean_node (integer_zerop (arg), type);
3676 case TRUTH_AND_EXPR:
3677 return build2 (TRUTH_OR_EXPR, type,
3678 invert_truthvalue (TREE_OPERAND (arg, 0)),
3679 invert_truthvalue (TREE_OPERAND (arg, 1)));
3682 return build2 (TRUTH_AND_EXPR, type,
3683 invert_truthvalue (TREE_OPERAND (arg, 0)),
3684 invert_truthvalue (TREE_OPERAND (arg, 1)));
3686 case TRUTH_XOR_EXPR:
3687 /* Here we can invert either operand. We invert the first operand
3688 unless the second operand is a TRUTH_NOT_EXPR in which case our
3689 result is the XOR of the first operand with the inside of the
3690 negation of the second operand. */
3692 if (TREE_CODE (TREE_OPERAND (arg, 1)) == TRUTH_NOT_EXPR)
3693 return build2 (TRUTH_XOR_EXPR, type, TREE_OPERAND (arg, 0),
3694 TREE_OPERAND (TREE_OPERAND (arg, 1), 0));
3696 return build2 (TRUTH_XOR_EXPR, type,
3697 invert_truthvalue (TREE_OPERAND (arg, 0)),
3698 TREE_OPERAND (arg, 1));
3700 case TRUTH_ANDIF_EXPR:
3701 return build2 (TRUTH_ORIF_EXPR, type,
3702 invert_truthvalue (TREE_OPERAND (arg, 0)),
3703 invert_truthvalue (TREE_OPERAND (arg, 1)));
3705 case TRUTH_ORIF_EXPR:
3706 return build2 (TRUTH_ANDIF_EXPR, type,
3707 invert_truthvalue (TREE_OPERAND (arg, 0)),
3708 invert_truthvalue (TREE_OPERAND (arg, 1)));
3710 case TRUTH_NOT_EXPR:
3711 return TREE_OPERAND (arg, 0);
3715 tree arg1 = TREE_OPERAND (arg, 1);
3716 tree arg2 = TREE_OPERAND (arg, 2);
3717 /* A COND_EXPR may have a throw as one operand, which
3718 then has void type. Just leave void operands
3720 return build3 (COND_EXPR, type, TREE_OPERAND (arg, 0),
3721 VOID_TYPE_P (TREE_TYPE (arg1))
3722 ? arg1 : invert_truthvalue (arg1),
3723 VOID_TYPE_P (TREE_TYPE (arg2))
3724 ? arg2 : invert_truthvalue (arg2));
3728 return build2 (COMPOUND_EXPR, type, TREE_OPERAND (arg, 0),
3729 invert_truthvalue (TREE_OPERAND (arg, 1)));
3731 case NON_LVALUE_EXPR:
3732 return invert_truthvalue (TREE_OPERAND (arg, 0));
3735 if (TREE_CODE (TREE_TYPE (arg)) == BOOLEAN_TYPE)
3736 return build1 (TRUTH_NOT_EXPR, type, arg);
3740 return build1 (TREE_CODE (arg), type,
3741 invert_truthvalue (TREE_OPERAND (arg, 0)));
3744 if (!integer_onep (TREE_OPERAND (arg, 1)))
3746 return build2 (EQ_EXPR, type, arg,
3747 build_int_cst (type, 0));
3750 return build1 (TRUTH_NOT_EXPR, type, arg);
3752 case CLEANUP_POINT_EXPR:
3753 return build1 (CLEANUP_POINT_EXPR, type,
3754 invert_truthvalue (TREE_OPERAND (arg, 0)));
3763 /* Return a simplified tree node for the truth-negation of ARG. This
3764 never alters ARG itself. We assume that ARG is an operation that
3765 returns a truth value (0 or 1).
3767 FIXME: one would think we would fold the result, but it causes
3768 problems with the dominator optimizer. */
3771 invert_truthvalue (tree arg)
3775 if (TREE_CODE (arg) == ERROR_MARK)
3778 tem = fold_truth_not_expr (arg);
3780 tem = build1 (TRUTH_NOT_EXPR, TREE_TYPE (arg), arg);
3785 /* Given a bit-wise operation CODE applied to ARG0 and ARG1, see if both
3786 operands are another bit-wise operation with a common input. If so,
3787 distribute the bit operations to save an operation and possibly two if
3788 constants are involved. For example, convert
3789 (A | B) & (A | C) into A | (B & C)
3790 Further simplification will occur if B and C are constants.
3792 If this optimization cannot be done, 0 will be returned. */
3795 distribute_bit_expr (enum tree_code code, tree type, tree arg0, tree arg1)
3800 if (TREE_CODE (arg0) != TREE_CODE (arg1)
3801 || TREE_CODE (arg0) == code
3802 || (TREE_CODE (arg0) != BIT_AND_EXPR
3803 && TREE_CODE (arg0) != BIT_IOR_EXPR))
3806 if (operand_equal_p (TREE_OPERAND (arg0, 0), TREE_OPERAND (arg1, 0), 0))
3808 common = TREE_OPERAND (arg0, 0);
3809 left = TREE_OPERAND (arg0, 1);
3810 right = TREE_OPERAND (arg1, 1);
3812 else if (operand_equal_p (TREE_OPERAND (arg0, 0), TREE_OPERAND (arg1, 1), 0))
3814 common = TREE_OPERAND (arg0, 0);
3815 left = TREE_OPERAND (arg0, 1);
3816 right = TREE_OPERAND (arg1, 0);
3818 else if (operand_equal_p (TREE_OPERAND (arg0, 1), TREE_OPERAND (arg1, 0), 0))
3820 common = TREE_OPERAND (arg0, 1);
3821 left = TREE_OPERAND (arg0, 0);
3822 right = TREE_OPERAND (arg1, 1);
3824 else if (operand_equal_p (TREE_OPERAND (arg0, 1), TREE_OPERAND (arg1, 1), 0))
3826 common = TREE_OPERAND (arg0, 1);
3827 left = TREE_OPERAND (arg0, 0);
3828 right = TREE_OPERAND (arg1, 0);
3833 common = fold_convert (type, common);
3834 left = fold_convert (type, left);
3835 right = fold_convert (type, right);
3836 return fold_build2 (TREE_CODE (arg0), type, common,
3837 fold_build2 (code, type, left, right));
3840 /* Knowing that ARG0 and ARG1 are both RDIV_EXPRs, simplify a binary operation
3841 with code CODE. This optimization is unsafe. */
3843 distribute_real_division (enum tree_code code, tree type, tree arg0, tree arg1)
3845 bool mul0 = TREE_CODE (arg0) == MULT_EXPR;
3846 bool mul1 = TREE_CODE (arg1) == MULT_EXPR;
3848 /* (A / C) +- (B / C) -> (A +- B) / C. */
3850 && operand_equal_p (TREE_OPERAND (arg0, 1),
3851 TREE_OPERAND (arg1, 1), 0))
3852 return fold_build2 (mul0 ? MULT_EXPR : RDIV_EXPR, type,
3853 fold_build2 (code, type,
3854 TREE_OPERAND (arg0, 0),
3855 TREE_OPERAND (arg1, 0)),
3856 TREE_OPERAND (arg0, 1));
3858 /* (A / C1) +- (A / C2) -> A * (1 / C1 +- 1 / C2). */
3859 if (operand_equal_p (TREE_OPERAND (arg0, 0),
3860 TREE_OPERAND (arg1, 0), 0)
3861 && TREE_CODE (TREE_OPERAND (arg0, 1)) == REAL_CST
3862 && TREE_CODE (TREE_OPERAND (arg1, 1)) == REAL_CST)
3864 REAL_VALUE_TYPE r0, r1;
3865 r0 = TREE_REAL_CST (TREE_OPERAND (arg0, 1));
3866 r1 = TREE_REAL_CST (TREE_OPERAND (arg1, 1));
3868 real_arithmetic (&r0, RDIV_EXPR, &dconst1, &r0);
3870 real_arithmetic (&r1, RDIV_EXPR, &dconst1, &r1);
3871 real_arithmetic (&r0, code, &r0, &r1);
3872 return fold_build2 (MULT_EXPR, type,
3873 TREE_OPERAND (arg0, 0),
3874 build_real (type, r0));
3880 /* Return a BIT_FIELD_REF of type TYPE to refer to BITSIZE bits of INNER
3881 starting at BITPOS. The field is unsigned if UNSIGNEDP is nonzero. */
3884 make_bit_field_ref (tree inner, tree type, HOST_WIDE_INT bitsize,
3885 HOST_WIDE_INT bitpos, int unsignedp)
3887 tree result, bftype;
3891 tree size = TYPE_SIZE (TREE_TYPE (inner));
3892 if ((INTEGRAL_TYPE_P (TREE_TYPE (inner))
3893 || POINTER_TYPE_P (TREE_TYPE (inner)))
3894 && host_integerp (size, 0)
3895 && tree_low_cst (size, 0) == bitsize)
3896 return fold_convert (type, inner);
3900 if (TYPE_PRECISION (bftype) != bitsize
3901 || TYPE_UNSIGNED (bftype) == !unsignedp)
3902 bftype = build_nonstandard_integer_type (bitsize, 0);
3904 result = build3 (BIT_FIELD_REF, bftype, inner,
3905 size_int (bitsize), bitsize_int (bitpos));
3908 result = fold_convert (type, result);
3913 /* Optimize a bit-field compare.
3915 There are two cases: First is a compare against a constant and the
3916 second is a comparison of two items where the fields are at the same
3917 bit position relative to the start of a chunk (byte, halfword, word)
3918 large enough to contain it. In these cases we can avoid the shift
3919 implicit in bitfield extractions.
3921 For constants, we emit a compare of the shifted constant with the
3922 BIT_AND_EXPR of a mask and a byte, halfword, or word of the operand being
3923 compared. For two fields at the same position, we do the ANDs with the
3924 similar mask and compare the result of the ANDs.
3926 CODE is the comparison code, known to be either NE_EXPR or EQ_EXPR.
3927 COMPARE_TYPE is the type of the comparison, and LHS and RHS
3928 are the left and right operands of the comparison, respectively.
3930 If the optimization described above can be done, we return the resulting
3931 tree. Otherwise we return zero. */
3934 optimize_bit_field_compare (enum tree_code code, tree compare_type,
3937 HOST_WIDE_INT lbitpos, lbitsize, rbitpos, rbitsize, nbitpos, nbitsize;
3938 tree type = TREE_TYPE (lhs);
3939 tree signed_type, unsigned_type;
3940 int const_p = TREE_CODE (rhs) == INTEGER_CST;
3941 enum machine_mode lmode, rmode, nmode;
3942 int lunsignedp, runsignedp;
3943 int lvolatilep = 0, rvolatilep = 0;
3944 tree linner, rinner = NULL_TREE;
3948 /* Get all the information about the extractions being done. If the bit size
3949 if the same as the size of the underlying object, we aren't doing an
3950 extraction at all and so can do nothing. We also don't want to
3951 do anything if the inner expression is a PLACEHOLDER_EXPR since we
3952 then will no longer be able to replace it. */
3953 linner = get_inner_reference (lhs, &lbitsize, &lbitpos, &offset, &lmode,
3954 &lunsignedp, &lvolatilep, false);
3955 if (linner == lhs || lbitsize == GET_MODE_BITSIZE (lmode) || lbitsize < 0
3956 || offset != 0 || TREE_CODE (linner) == PLACEHOLDER_EXPR)
3961 /* If this is not a constant, we can only do something if bit positions,
3962 sizes, and signedness are the same. */
3963 rinner = get_inner_reference (rhs, &rbitsize, &rbitpos, &offset, &rmode,
3964 &runsignedp, &rvolatilep, false);
3966 if (rinner == rhs || lbitpos != rbitpos || lbitsize != rbitsize
3967 || lunsignedp != runsignedp || offset != 0
3968 || TREE_CODE (rinner) == PLACEHOLDER_EXPR)
3972 /* See if we can find a mode to refer to this field. We should be able to,
3973 but fail if we can't. */
3974 nmode = get_best_mode (lbitsize, lbitpos,
3975 const_p ? TYPE_ALIGN (TREE_TYPE (linner))
3976 : MIN (TYPE_ALIGN (TREE_TYPE (linner)),
3977 TYPE_ALIGN (TREE_TYPE (rinner))),
3978 word_mode, lvolatilep || rvolatilep);
3979 if (nmode == VOIDmode)
3982 /* Set signed and unsigned types of the precision of this mode for the
3984 signed_type = lang_hooks.types.type_for_mode (nmode, 0);
3985 unsigned_type = lang_hooks.types.type_for_mode (nmode, 1);
3987 /* Compute the bit position and size for the new reference and our offset
3988 within it. If the new reference is the same size as the original, we
3989 won't optimize anything, so return zero. */
3990 nbitsize = GET_MODE_BITSIZE (nmode);
3991 nbitpos = lbitpos & ~ (nbitsize - 1);
3993 if (nbitsize == lbitsize)
3996 if (BYTES_BIG_ENDIAN)
3997 lbitpos = nbitsize - lbitsize - lbitpos;
3999 /* Make the mask to be used against the extracted field. */
4000 mask = build_int_cst_type (unsigned_type, -1);
4001 mask = const_binop (LSHIFT_EXPR, mask, size_int (nbitsize - lbitsize), 0);
4002 mask = const_binop (RSHIFT_EXPR, mask,
4003 size_int (nbitsize - lbitsize - lbitpos), 0);
4006 /* If not comparing with constant, just rework the comparison
4008 return fold_build2 (code, compare_type,
4009 fold_build2 (BIT_AND_EXPR, unsigned_type,
4010 make_bit_field_ref (linner,
4015 fold_build2 (BIT_AND_EXPR, unsigned_type,
4016 make_bit_field_ref (rinner,
4022 /* Otherwise, we are handling the constant case. See if the constant is too
4023 big for the field. Warn and return a tree of for 0 (false) if so. We do
4024 this not only for its own sake, but to avoid having to test for this
4025 error case below. If we didn't, we might generate wrong code.
4027 For unsigned fields, the constant shifted right by the field length should
4028 be all zero. For signed fields, the high-order bits should agree with
4033 if (! integer_zerop (const_binop (RSHIFT_EXPR,
4034 fold_convert (unsigned_type, rhs),
4035 size_int (lbitsize), 0)))
4037 warning (0, "comparison is always %d due to width of bit-field",
4039 return constant_boolean_node (code == NE_EXPR, compare_type);
4044 tree tem = const_binop (RSHIFT_EXPR, fold_convert (signed_type, rhs),
4045 size_int (lbitsize - 1), 0);
4046 if (! integer_zerop (tem) && ! integer_all_onesp (tem))
4048 warning (0, "comparison is always %d due to width of bit-field",
4050 return constant_boolean_node (code == NE_EXPR, compare_type);
4054 /* Single-bit compares should always be against zero. */
4055 if (lbitsize == 1 && ! integer_zerop (rhs))
4057 code = code == EQ_EXPR ? NE_EXPR : EQ_EXPR;
4058 rhs = build_int_cst (type, 0);
4061 /* Make a new bitfield reference, shift the constant over the
4062 appropriate number of bits and mask it with the computed mask
4063 (in case this was a signed field). If we changed it, make a new one. */
4064 lhs = make_bit_field_ref (linner, unsigned_type, nbitsize, nbitpos, 1);
4067 TREE_SIDE_EFFECTS (lhs) = 1;
4068 TREE_THIS_VOLATILE (lhs) = 1;
4071 rhs = const_binop (BIT_AND_EXPR,
4072 const_binop (LSHIFT_EXPR,
4073 fold_convert (unsigned_type, rhs),
4074 size_int (lbitpos), 0),
4077 return build2 (code, compare_type,
4078 build2 (BIT_AND_EXPR, unsigned_type, lhs, mask),
4082 /* Subroutine for fold_truthop: decode a field reference.
4084 If EXP is a comparison reference, we return the innermost reference.
4086 *PBITSIZE is set to the number of bits in the reference, *PBITPOS is
4087 set to the starting bit number.
4089 If the innermost field can be completely contained in a mode-sized
4090 unit, *PMODE is set to that mode. Otherwise, it is set to VOIDmode.
4092 *PVOLATILEP is set to 1 if the any expression encountered is volatile;
4093 otherwise it is not changed.
4095 *PUNSIGNEDP is set to the signedness of the field.
4097 *PMASK is set to the mask used. This is either contained in a
4098 BIT_AND_EXPR or derived from the width of the field.
4100 *PAND_MASK is set to the mask found in a BIT_AND_EXPR, if any.
4102 Return 0 if this is not a component reference or is one that we can't
4103 do anything with. */
4106 decode_field_reference (tree exp, HOST_WIDE_INT *pbitsize,
4107 HOST_WIDE_INT *pbitpos, enum machine_mode *pmode,
4108 int *punsignedp, int *pvolatilep,
4109 tree *pmask, tree *pand_mask)
4111 tree outer_type = 0;
4113 tree mask, inner, offset;
4115 unsigned int precision;
4117 /* All the optimizations using this function assume integer fields.
4118 There are problems with FP fields since the type_for_size call
4119 below can fail for, e.g., XFmode. */
4120 if (! INTEGRAL_TYPE_P (TREE_TYPE (exp)))
4123 /* We are interested in the bare arrangement of bits, so strip everything
4124 that doesn't affect the machine mode. However, record the type of the
4125 outermost expression if it may matter below. */
4126 if (CONVERT_EXPR_P (exp)
4127 || TREE_CODE (exp) == NON_LVALUE_EXPR)
4128 outer_type = TREE_TYPE (exp);
4131 if (TREE_CODE (exp) == BIT_AND_EXPR)
4133 and_mask = TREE_OPERAND (exp, 1);
4134 exp = TREE_OPERAND (exp, 0);
4135 STRIP_NOPS (exp); STRIP_NOPS (and_mask);
4136 if (TREE_CODE (and_mask) != INTEGER_CST)
4140 inner = get_inner_reference (exp, pbitsize, pbitpos, &offset, pmode,
4141 punsignedp, pvolatilep, false);
4142 if ((inner == exp && and_mask == 0)
4143 || *pbitsize < 0 || offset != 0
4144 || TREE_CODE (inner) == PLACEHOLDER_EXPR)
4147 /* If the number of bits in the reference is the same as the bitsize of
4148 the outer type, then the outer type gives the signedness. Otherwise
4149 (in case of a small bitfield) the signedness is unchanged. */
4150 if (outer_type && *pbitsize == TYPE_PRECISION (outer_type))
4151 *punsignedp = TYPE_UNSIGNED (outer_type);
4153 /* Compute the mask to access the bitfield. */
4154 unsigned_type = lang_hooks.types.type_for_size (*pbitsize, 1);
4155 precision = TYPE_PRECISION (unsigned_type);
4157 mask = build_int_cst_type (unsigned_type, -1);
4159 mask = const_binop (LSHIFT_EXPR, mask, size_int (precision - *pbitsize), 0);
4160 mask = const_binop (RSHIFT_EXPR, mask, size_int (precision - *pbitsize), 0);
4162 /* Merge it with the mask we found in the BIT_AND_EXPR, if any. */
4164 mask = fold_build2 (BIT_AND_EXPR, unsigned_type,
4165 fold_convert (unsigned_type, and_mask), mask);
4168 *pand_mask = and_mask;
4172 /* Return nonzero if MASK represents a mask of SIZE ones in the low-order
4176 all_ones_mask_p (const_tree mask, int size)
4178 tree type = TREE_TYPE (mask);
4179 unsigned int precision = TYPE_PRECISION (type);
4182 tmask = build_int_cst_type (signed_type_for (type), -1);
4185 tree_int_cst_equal (mask,
4186 const_binop (RSHIFT_EXPR,
4187 const_binop (LSHIFT_EXPR, tmask,
4188 size_int (precision - size),
4190 size_int (precision - size), 0));
4193 /* Subroutine for fold: determine if VAL is the INTEGER_CONST that
4194 represents the sign bit of EXP's type. If EXP represents a sign
4195 or zero extension, also test VAL against the unextended type.
4196 The return value is the (sub)expression whose sign bit is VAL,
4197 or NULL_TREE otherwise. */
4200 sign_bit_p (tree exp, const_tree val)
4202 unsigned HOST_WIDE_INT mask_lo, lo;
4203 HOST_WIDE_INT mask_hi, hi;
4207 /* Tree EXP must have an integral type. */
4208 t = TREE_TYPE (exp);
4209 if (! INTEGRAL_TYPE_P (t))
4212 /* Tree VAL must be an integer constant. */
4213 if (TREE_CODE (val) != INTEGER_CST
4214 || TREE_OVERFLOW (val))
4217 width = TYPE_PRECISION (t);
4218 if (width > HOST_BITS_PER_WIDE_INT)
4220 hi = (unsigned HOST_WIDE_INT) 1 << (width - HOST_BITS_PER_WIDE_INT - 1);
4223 mask_hi = ((unsigned HOST_WIDE_INT) -1
4224 >> (2 * HOST_BITS_PER_WIDE_INT - width));
4230 lo = (unsigned HOST_WIDE_INT) 1 << (width - 1);
4233 mask_lo = ((unsigned HOST_WIDE_INT) -1
4234 >> (HOST_BITS_PER_WIDE_INT - width));
4237 /* We mask off those bits beyond TREE_TYPE (exp) so that we can
4238 treat VAL as if it were unsigned. */
4239 if ((TREE_INT_CST_HIGH (val) & mask_hi) == hi
4240 && (TREE_INT_CST_LOW (val) & mask_lo) == lo)
4243 /* Handle extension from a narrower type. */
4244 if (TREE_CODE (exp) == NOP_EXPR
4245 && TYPE_PRECISION (TREE_TYPE (TREE_OPERAND (exp, 0))) < width)
4246 return sign_bit_p (TREE_OPERAND (exp, 0), val);
4251 /* Subroutine for fold_truthop: determine if an operand is simple enough
4252 to be evaluated unconditionally. */
4255 simple_operand_p (const_tree exp)
4257 /* Strip any conversions that don't change the machine mode. */
4260 return (CONSTANT_CLASS_P (exp)
4261 || TREE_CODE (exp) == SSA_NAME
4263 && ! TREE_ADDRESSABLE (exp)
4264 && ! TREE_THIS_VOLATILE (exp)
4265 && ! DECL_NONLOCAL (exp)
4266 /* Don't regard global variables as simple. They may be
4267 allocated in ways unknown to the compiler (shared memory,
4268 #pragma weak, etc). */
4269 && ! TREE_PUBLIC (exp)
4270 && ! DECL_EXTERNAL (exp)
4271 /* Loading a static variable is unduly expensive, but global
4272 registers aren't expensive. */
4273 && (! TREE_STATIC (exp) || DECL_REGISTER (exp))));
4276 /* The following functions are subroutines to fold_range_test and allow it to
4277 try to change a logical combination of comparisons into a range test.
4280 X == 2 || X == 3 || X == 4 || X == 5
4284 (unsigned) (X - 2) <= 3
4286 We describe each set of comparisons as being either inside or outside
4287 a range, using a variable named like IN_P, and then describe the
4288 range with a lower and upper bound. If one of the bounds is omitted,
4289 it represents either the highest or lowest value of the type.
4291 In the comments below, we represent a range by two numbers in brackets
4292 preceded by a "+" to designate being inside that range, or a "-" to
4293 designate being outside that range, so the condition can be inverted by
4294 flipping the prefix. An omitted bound is represented by a "-". For
4295 example, "- [-, 10]" means being outside the range starting at the lowest
4296 possible value and ending at 10, in other words, being greater than 10.
4297 The range "+ [-, -]" is always true and hence the range "- [-, -]" is
4300 We set up things so that the missing bounds are handled in a consistent
4301 manner so neither a missing bound nor "true" and "false" need to be
4302 handled using a special case. */
4304 /* Return the result of applying CODE to ARG0 and ARG1, but handle the case
4305 of ARG0 and/or ARG1 being omitted, meaning an unlimited range. UPPER0_P
4306 and UPPER1_P are nonzero if the respective argument is an upper bound
4307 and zero for a lower. TYPE, if nonzero, is the type of the result; it
4308 must be specified for a comparison. ARG1 will be converted to ARG0's
4309 type if both are specified. */
4312 range_binop (enum tree_code code, tree type, tree arg0, int upper0_p,
4313 tree arg1, int upper1_p)
4319 /* If neither arg represents infinity, do the normal operation.
4320 Else, if not a comparison, return infinity. Else handle the special
4321 comparison rules. Note that most of the cases below won't occur, but
4322 are handled for consistency. */
4324 if (arg0 != 0 && arg1 != 0)
4326 tem = fold_build2 (code, type != 0 ? type : TREE_TYPE (arg0),
4327 arg0, fold_convert (TREE_TYPE (arg0), arg1));
4329 return TREE_CODE (tem) == INTEGER_CST ? tem : 0;
4332 if (TREE_CODE_CLASS (code) != tcc_comparison)
4335 /* Set SGN[01] to -1 if ARG[01] is a lower bound, 1 for upper, and 0
4336 for neither. In real maths, we cannot assume open ended ranges are
4337 the same. But, this is computer arithmetic, where numbers are finite.
4338 We can therefore make the transformation of any unbounded range with
4339 the value Z, Z being greater than any representable number. This permits
4340 us to treat unbounded ranges as equal. */
4341 sgn0 = arg0 != 0 ? 0 : (upper0_p ? 1 : -1);
4342 sgn1 = arg1 != 0 ? 0 : (upper1_p ? 1 : -1);
4346 result = sgn0 == sgn1;
4349 result = sgn0 != sgn1;
4352 result = sgn0 < sgn1;
4355 result = sgn0 <= sgn1;
4358 result = sgn0 > sgn1;
4361 result = sgn0 >= sgn1;
4367 return constant_boolean_node (result, type);
4370 /* Given EXP, a logical expression, set the range it is testing into
4371 variables denoted by PIN_P, PLOW, and PHIGH. Return the expression
4372 actually being tested. *PLOW and *PHIGH will be made of the same
4373 type as the returned expression. If EXP is not a comparison, we
4374 will most likely not be returning a useful value and range. Set
4375 *STRICT_OVERFLOW_P to true if the return value is only valid
4376 because signed overflow is undefined; otherwise, do not change
4377 *STRICT_OVERFLOW_P. */
4380 make_range (tree exp, int *pin_p, tree *plow, tree *phigh,
4381 bool *strict_overflow_p)
4383 enum tree_code code;
4384 tree arg0 = NULL_TREE, arg1 = NULL_TREE;
4385 tree exp_type = NULL_TREE, arg0_type = NULL_TREE;
4387 tree low, high, n_low, n_high;
4389 /* Start with simply saying "EXP != 0" and then look at the code of EXP
4390 and see if we can refine the range. Some of the cases below may not
4391 happen, but it doesn't seem worth worrying about this. We "continue"
4392 the outer loop when we've changed something; otherwise we "break"
4393 the switch, which will "break" the while. */
4396 low = high = build_int_cst (TREE_TYPE (exp), 0);
4400 code = TREE_CODE (exp);
4401 exp_type = TREE_TYPE (exp);
4403 if (IS_EXPR_CODE_CLASS (TREE_CODE_CLASS (code)))
4405 if (TREE_OPERAND_LENGTH (exp) > 0)
4406 arg0 = TREE_OPERAND (exp, 0);
4407 if (TREE_CODE_CLASS (code) == tcc_comparison
4408 || TREE_CODE_CLASS (code) == tcc_unary
4409 || TREE_CODE_CLASS (code) == tcc_binary)
4410 arg0_type = TREE_TYPE (arg0);
4411 if (TREE_CODE_CLASS (code) == tcc_binary
4412 || TREE_CODE_CLASS (code) == tcc_comparison
4413 || (TREE_CODE_CLASS (code) == tcc_expression
4414 && TREE_OPERAND_LENGTH (exp) > 1))
4415 arg1 = TREE_OPERAND (exp, 1);
4420 case TRUTH_NOT_EXPR:
4421 in_p = ! in_p, exp = arg0;
4424 case EQ_EXPR: case NE_EXPR:
4425 case LT_EXPR: case LE_EXPR: case GE_EXPR: case GT_EXPR:
4426 /* We can only do something if the range is testing for zero
4427 and if the second operand is an integer constant. Note that
4428 saying something is "in" the range we make is done by
4429 complementing IN_P since it will set in the initial case of
4430 being not equal to zero; "out" is leaving it alone. */
4431 if (low == 0 || high == 0
4432 || ! integer_zerop (low) || ! integer_zerop (high)
4433 || TREE_CODE (arg1) != INTEGER_CST)
4438 case NE_EXPR: /* - [c, c] */
4441 case EQ_EXPR: /* + [c, c] */
4442 in_p = ! in_p, low = high = arg1;
4444 case GT_EXPR: /* - [-, c] */
4445 low = 0, high = arg1;
4447 case GE_EXPR: /* + [c, -] */
4448 in_p = ! in_p, low = arg1, high = 0;
4450 case LT_EXPR: /* - [c, -] */
4451 low = arg1, high = 0;
4453 case LE_EXPR: /* + [-, c] */
4454 in_p = ! in_p, low = 0, high = arg1;
4460 /* If this is an unsigned comparison, we also know that EXP is
4461 greater than or equal to zero. We base the range tests we make
4462 on that fact, so we record it here so we can parse existing
4463 range tests. We test arg0_type since often the return type
4464 of, e.g. EQ_EXPR, is boolean. */
4465 if (TYPE_UNSIGNED (arg0_type) && (low == 0 || high == 0))
4467 if (! merge_ranges (&n_in_p, &n_low, &n_high,
4469 build_int_cst (arg0_type, 0),
4473 in_p = n_in_p, low = n_low, high = n_high;
4475 /* If the high bound is missing, but we have a nonzero low
4476 bound, reverse the range so it goes from zero to the low bound
4478 if (high == 0 && low && ! integer_zerop (low))
4481 high = range_binop (MINUS_EXPR, NULL_TREE, low, 0,
4482 integer_one_node, 0);
4483 low = build_int_cst (arg0_type, 0);
4491 /* (-x) IN [a,b] -> x in [-b, -a] */
4492 n_low = range_binop (MINUS_EXPR, exp_type,
4493 build_int_cst (exp_type, 0),
4495 n_high = range_binop (MINUS_EXPR, exp_type,
4496 build_int_cst (exp_type, 0),
4498 low = n_low, high = n_high;
4504 exp = build2 (MINUS_EXPR, exp_type, negate_expr (arg0),
4505 build_int_cst (exp_type, 1));
4508 case PLUS_EXPR: case MINUS_EXPR:
4509 if (TREE_CODE (arg1) != INTEGER_CST)
4512 /* If flag_wrapv and ARG0_TYPE is signed, then we cannot
4513 move a constant to the other side. */
4514 if (!TYPE_UNSIGNED (arg0_type)
4515 && !TYPE_OVERFLOW_UNDEFINED (arg0_type))
4518 /* If EXP is signed, any overflow in the computation is undefined,
4519 so we don't worry about it so long as our computations on
4520 the bounds don't overflow. For unsigned, overflow is defined
4521 and this is exactly the right thing. */
4522 n_low = range_binop (code == MINUS_EXPR ? PLUS_EXPR : MINUS_EXPR,
4523 arg0_type, low, 0, arg1, 0);
4524 n_high = range_binop (code == MINUS_EXPR ? PLUS_EXPR : MINUS_EXPR,
4525 arg0_type, high, 1, arg1, 0);
4526 if ((n_low != 0 && TREE_OVERFLOW (n_low))
4527 || (n_high != 0 && TREE_OVERFLOW (n_high)))
4530 if (TYPE_OVERFLOW_UNDEFINED (arg0_type))
4531 *strict_overflow_p = true;
4533 /* Check for an unsigned range which has wrapped around the maximum
4534 value thus making n_high < n_low, and normalize it. */
4535 if (n_low && n_high && tree_int_cst_lt (n_high, n_low))
4537 low = range_binop (PLUS_EXPR, arg0_type, n_high, 0,
4538 integer_one_node, 0);
4539 high = range_binop (MINUS_EXPR, arg0_type, n_low, 0,
4540 integer_one_node, 0);
4542 /* If the range is of the form +/- [ x+1, x ], we won't
4543 be able to normalize it. But then, it represents the
4544 whole range or the empty set, so make it
4546 if (tree_int_cst_equal (n_low, low)
4547 && tree_int_cst_equal (n_high, high))
4553 low = n_low, high = n_high;
4558 CASE_CONVERT: case NON_LVALUE_EXPR:
4559 if (TYPE_PRECISION (arg0_type) > TYPE_PRECISION (exp_type))
4562 if (! INTEGRAL_TYPE_P (arg0_type)
4563 || (low != 0 && ! int_fits_type_p (low, arg0_type))
4564 || (high != 0 && ! int_fits_type_p (high, arg0_type)))
4567 n_low = low, n_high = high;
4570 n_low = fold_convert (arg0_type, n_low);
4573 n_high = fold_convert (arg0_type, n_high);
4576 /* If we're converting arg0 from an unsigned type, to exp,
4577 a signed type, we will be doing the comparison as unsigned.
4578 The tests above have already verified that LOW and HIGH
4581 So we have to ensure that we will handle large unsigned
4582 values the same way that the current signed bounds treat
4585 if (!TYPE_UNSIGNED (exp_type) && TYPE_UNSIGNED (arg0_type))
4589 /* For fixed-point modes, we need to pass the saturating flag
4590 as the 2nd parameter. */
4591 if (ALL_FIXED_POINT_MODE_P (TYPE_MODE (arg0_type)))
4592 equiv_type = lang_hooks.types.type_for_mode
4593 (TYPE_MODE (arg0_type),
4594 TYPE_SATURATING (arg0_type));
4596 equiv_type = lang_hooks.types.type_for_mode
4597 (TYPE_MODE (arg0_type), 1);
4599 /* A range without an upper bound is, naturally, unbounded.
4600 Since convert would have cropped a very large value, use
4601 the max value for the destination type. */
4603 = TYPE_MAX_VALUE (equiv_type) ? TYPE_MAX_VALUE (equiv_type)
4604 : TYPE_MAX_VALUE (arg0_type);
4606 if (TYPE_PRECISION (exp_type) == TYPE_PRECISION (arg0_type))
4607 high_positive = fold_build2 (RSHIFT_EXPR, arg0_type,
4608 fold_convert (arg0_type,
4610 build_int_cst (arg0_type, 1));
4612 /* If the low bound is specified, "and" the range with the
4613 range for which the original unsigned value will be
4617 if (! merge_ranges (&n_in_p, &n_low, &n_high,
4618 1, n_low, n_high, 1,
4619 fold_convert (arg0_type,
4624 in_p = (n_in_p == in_p);
4628 /* Otherwise, "or" the range with the range of the input
4629 that will be interpreted as negative. */
4630 if (! merge_ranges (&n_in_p, &n_low, &n_high,
4631 0, n_low, n_high, 1,
4632 fold_convert (arg0_type,
4637 in_p = (in_p != n_in_p);
4642 low = n_low, high = n_high;
4652 /* If EXP is a constant, we can evaluate whether this is true or false. */
4653 if (TREE_CODE (exp) == INTEGER_CST)
4655 in_p = in_p == (integer_onep (range_binop (GE_EXPR, integer_type_node,
4657 && integer_onep (range_binop (LE_EXPR, integer_type_node,
4663 *pin_p = in_p, *plow = low, *phigh = high;
4667 /* Given a range, LOW, HIGH, and IN_P, an expression, EXP, and a result
4668 type, TYPE, return an expression to test if EXP is in (or out of, depending
4669 on IN_P) the range. Return 0 if the test couldn't be created. */
4672 build_range_check (tree type, tree exp, int in_p, tree low, tree high)
4674 tree etype = TREE_TYPE (exp);
4677 #ifdef HAVE_canonicalize_funcptr_for_compare
4678 /* Disable this optimization for function pointer expressions
4679 on targets that require function pointer canonicalization. */
4680 if (HAVE_canonicalize_funcptr_for_compare
4681 && TREE_CODE (etype) == POINTER_TYPE
4682 && TREE_CODE (TREE_TYPE (etype)) == FUNCTION_TYPE)
4688 value = build_range_check (type, exp, 1, low, high);
4690 return invert_truthvalue (value);
4695 if (low == 0 && high == 0)
4696 return build_int_cst (type, 1);
4699 return fold_build2 (LE_EXPR, type, exp,
4700 fold_convert (etype, high));
4703 return fold_build2 (GE_EXPR, type, exp,
4704 fold_convert (etype, low));
4706 if (operand_equal_p (low, high, 0))
4707 return fold_build2 (EQ_EXPR, type, exp,
4708 fold_convert (etype, low));
4710 if (integer_zerop (low))
4712 if (! TYPE_UNSIGNED (etype))
4714 etype = unsigned_type_for (etype);
4715 high = fold_convert (etype, high);
4716 exp = fold_convert (etype, exp);
4718 return build_range_check (type, exp, 1, 0, high);
4721 /* Optimize (c>=1) && (c<=127) into (signed char)c > 0. */
4722 if (integer_onep (low) && TREE_CODE (high) == INTEGER_CST)
4724 unsigned HOST_WIDE_INT lo;
4728 prec = TYPE_PRECISION (etype);
4729 if (prec <= HOST_BITS_PER_WIDE_INT)
4732 lo = ((unsigned HOST_WIDE_INT) 1 << (prec - 1)) - 1;
4736 hi = ((HOST_WIDE_INT) 1 << (prec - HOST_BITS_PER_WIDE_INT - 1)) - 1;
4737 lo = (unsigned HOST_WIDE_INT) -1;
4740 if (TREE_INT_CST_HIGH (high) == hi && TREE_INT_CST_LOW (high) == lo)
4742 if (TYPE_UNSIGNED (etype))
4744 tree signed_etype = signed_type_for (etype);
4745 if (TYPE_PRECISION (signed_etype) != TYPE_PRECISION (etype))
4747 = build_nonstandard_integer_type (TYPE_PRECISION (etype), 0);
4749 etype = signed_etype;
4750 exp = fold_convert (etype, exp);
4752 return fold_build2 (GT_EXPR, type, exp,
4753 build_int_cst (etype, 0));
4757 /* Optimize (c>=low) && (c<=high) into (c-low>=0) && (c-low<=high-low).
4758 This requires wrap-around arithmetics for the type of the expression. */
4759 switch (TREE_CODE (etype))
4762 /* There is no requirement that LOW be within the range of ETYPE
4763 if the latter is a subtype. It must, however, be within the base
4764 type of ETYPE. So be sure we do the subtraction in that type. */
4765 if (TREE_TYPE (etype))
4766 etype = TREE_TYPE (etype);
4771 etype = lang_hooks.types.type_for_size (TYPE_PRECISION (etype),
4772 TYPE_UNSIGNED (etype));
4779 /* If we don't have wrap-around arithmetics upfront, try to force it. */
4780 if (TREE_CODE (etype) == INTEGER_TYPE
4781 && !TYPE_OVERFLOW_WRAPS (etype))
4783 tree utype, minv, maxv;
4785 /* Check if (unsigned) INT_MAX + 1 == (unsigned) INT_MIN
4786 for the type in question, as we rely on this here. */
4787 utype = unsigned_type_for (etype);
4788 maxv = fold_convert (utype, TYPE_MAX_VALUE (etype));
4789 maxv = range_binop (PLUS_EXPR, NULL_TREE, maxv, 1,
4790 integer_one_node, 1);
4791 minv = fold_convert (utype, TYPE_MIN_VALUE (etype));
4793 if (integer_zerop (range_binop (NE_EXPR, integer_type_node,
4800 high = fold_convert (etype, high);
4801 low = fold_convert (etype, low);
4802 exp = fold_convert (etype, exp);
4804 value = const_binop (MINUS_EXPR, high, low, 0);
4807 if (POINTER_TYPE_P (etype))
4809 if (value != 0 && !TREE_OVERFLOW (value))
4811 low = fold_convert (sizetype, low);
4812 low = fold_build1 (NEGATE_EXPR, sizetype, low);
4813 return build_range_check (type,
4814 fold_build2 (POINTER_PLUS_EXPR, etype, exp, low),
4815 1, build_int_cst (etype, 0), value);
4820 if (value != 0 && !TREE_OVERFLOW (value))
4821 return build_range_check (type,
4822 fold_build2 (MINUS_EXPR, etype, exp, low),
4823 1, build_int_cst (etype, 0), value);
4828 /* Return the predecessor of VAL in its type, handling the infinite case. */
4831 range_predecessor (tree val)
4833 tree type = TREE_TYPE (val);
4835 if (INTEGRAL_TYPE_P (type)
4836 && operand_equal_p (val, TYPE_MIN_VALUE (type), 0))
4839 return range_binop (MINUS_EXPR, NULL_TREE, val, 0, integer_one_node, 0);
4842 /* Return the successor of VAL in its type, handling the infinite case. */
4845 range_successor (tree val)
4847 tree type = TREE_TYPE (val);
4849 if (INTEGRAL_TYPE_P (type)
4850 && operand_equal_p (val, TYPE_MAX_VALUE (type), 0))
4853 return range_binop (PLUS_EXPR, NULL_TREE, val, 0, integer_one_node, 0);
4856 /* Given two ranges, see if we can merge them into one. Return 1 if we
4857 can, 0 if we can't. Set the output range into the specified parameters. */
4860 merge_ranges (int *pin_p, tree *plow, tree *phigh, int in0_p, tree low0,
4861 tree high0, int in1_p, tree low1, tree high1)
4869 int lowequal = ((low0 == 0 && low1 == 0)
4870 || integer_onep (range_binop (EQ_EXPR, integer_type_node,
4871 low0, 0, low1, 0)));
4872 int highequal = ((high0 == 0 && high1 == 0)
4873 || integer_onep (range_binop (EQ_EXPR, integer_type_node,
4874 high0, 1, high1, 1)));
4876 /* Make range 0 be the range that starts first, or ends last if they
4877 start at the same value. Swap them if it isn't. */
4878 if (integer_onep (range_binop (GT_EXPR, integer_type_node,
4881 && integer_onep (range_binop (GT_EXPR, integer_type_node,
4882 high1, 1, high0, 1))))
4884 temp = in0_p, in0_p = in1_p, in1_p = temp;
4885 tem = low0, low0 = low1, low1 = tem;
4886 tem = high0, high0 = high1, high1 = tem;
4889 /* Now flag two cases, whether the ranges are disjoint or whether the
4890 second range is totally subsumed in the first. Note that the tests
4891 below are simplified by the ones above. */
4892 no_overlap = integer_onep (range_binop (LT_EXPR, integer_type_node,
4893 high0, 1, low1, 0));
4894 subset = integer_onep (range_binop (LE_EXPR, integer_type_node,
4895 high1, 1, high0, 1));
4897 /* We now have four cases, depending on whether we are including or
4898 excluding the two ranges. */
4901 /* If they don't overlap, the result is false. If the second range
4902 is a subset it is the result. Otherwise, the range is from the start
4903 of the second to the end of the first. */
4905 in_p = 0, low = high = 0;
4907 in_p = 1, low = low1, high = high1;
4909 in_p = 1, low = low1, high = high0;
4912 else if (in0_p && ! in1_p)
4914 /* If they don't overlap, the result is the first range. If they are
4915 equal, the result is false. If the second range is a subset of the
4916 first, and the ranges begin at the same place, we go from just after
4917 the end of the second range to the end of the first. If the second
4918 range is not a subset of the first, or if it is a subset and both
4919 ranges end at the same place, the range starts at the start of the
4920 first range and ends just before the second range.
4921 Otherwise, we can't describe this as a single range. */
4923 in_p = 1, low = low0, high = high0;
4924 else if (lowequal && highequal)
4925 in_p = 0, low = high = 0;
4926 else if (subset && lowequal)
4928 low = range_successor (high1);
4933 /* We are in the weird situation where high0 > high1 but
4934 high1 has no successor. Punt. */
4938 else if (! subset || highequal)
4941 high = range_predecessor (low1);
4945 /* low0 < low1 but low1 has no predecessor. Punt. */
4953 else if (! in0_p && in1_p)
4955 /* If they don't overlap, the result is the second range. If the second
4956 is a subset of the first, the result is false. Otherwise,
4957 the range starts just after the first range and ends at the
4958 end of the second. */
4960 in_p = 1, low = low1, high = high1;
4961 else if (subset || highequal)
4962 in_p = 0, low = high = 0;
4965 low = range_successor (high0);
4970 /* high1 > high0 but high0 has no successor. Punt. */
4978 /* The case where we are excluding both ranges. Here the complex case
4979 is if they don't overlap. In that case, the only time we have a
4980 range is if they are adjacent. If the second is a subset of the
4981 first, the result is the first. Otherwise, the range to exclude
4982 starts at the beginning of the first range and ends at the end of the
4986 if (integer_onep (range_binop (EQ_EXPR, integer_type_node,
4987 range_successor (high0),
4989 in_p = 0, low = low0, high = high1;
4992 /* Canonicalize - [min, x] into - [-, x]. */
4993 if (low0 && TREE_CODE (low0) == INTEGER_CST)
4994 switch (TREE_CODE (TREE_TYPE (low0)))
4997 if (TYPE_PRECISION (TREE_TYPE (low0))
4998 != GET_MODE_BITSIZE (TYPE_MODE (TREE_TYPE (low0))))
5002 if (tree_int_cst_equal (low0,
5003 TYPE_MIN_VALUE (TREE_TYPE (low0))))
5007 if (TYPE_UNSIGNED (TREE_TYPE (low0))
5008 && integer_zerop (low0))
5015 /* Canonicalize - [x, max] into - [x, -]. */
5016 if (high1 && TREE_CODE (high1) == INTEGER_CST)
5017 switch (TREE_CODE (TREE_TYPE (high1)))
5020 if (TYPE_PRECISION (TREE_TYPE (high1))
5021 != GET_MODE_BITSIZE (TYPE_MODE (TREE_TYPE (high1))))
5025 if (tree_int_cst_equal (high1,
5026 TYPE_MAX_VALUE (TREE_TYPE (high1))))
5030 if (TYPE_UNSIGNED (TREE_TYPE (high1))
5031 && integer_zerop (range_binop (PLUS_EXPR, NULL_TREE,
5033 integer_one_node, 1)))
5040 /* The ranges might be also adjacent between the maximum and
5041 minimum values of the given type. For
5042 - [{min,-}, x] and - [y, {max,-}] ranges where x + 1 < y
5043 return + [x + 1, y - 1]. */
5044 if (low0 == 0 && high1 == 0)
5046 low = range_successor (high0);
5047 high = range_predecessor (low1);
5048 if (low == 0 || high == 0)
5058 in_p = 0, low = low0, high = high0;
5060 in_p = 0, low = low0, high = high1;
5063 *pin_p = in_p, *plow = low, *phigh = high;
5068 /* Subroutine of fold, looking inside expressions of the form
5069 A op B ? A : C, where ARG0, ARG1 and ARG2 are the three operands
5070 of the COND_EXPR. This function is being used also to optimize
5071 A op B ? C : A, by reversing the comparison first.
5073 Return a folded expression whose code is not a COND_EXPR
5074 anymore, or NULL_TREE if no folding opportunity is found. */
5077 fold_cond_expr_with_comparison (tree type, tree arg0, tree arg1, tree arg2)
5079 enum tree_code comp_code = TREE_CODE (arg0);
5080 tree arg00 = TREE_OPERAND (arg0, 0);
5081 tree arg01 = TREE_OPERAND (arg0, 1);
5082 tree arg1_type = TREE_TYPE (arg1);
5088 /* If we have A op 0 ? A : -A, consider applying the following
5091 A == 0? A : -A same as -A
5092 A != 0? A : -A same as A
5093 A >= 0? A : -A same as abs (A)
5094 A > 0? A : -A same as abs (A)
5095 A <= 0? A : -A same as -abs (A)
5096 A < 0? A : -A same as -abs (A)
5098 None of these transformations work for modes with signed
5099 zeros. If A is +/-0, the first two transformations will
5100 change the sign of the result (from +0 to -0, or vice
5101 versa). The last four will fix the sign of the result,
5102 even though the original expressions could be positive or
5103 negative, depending on the sign of A.
5105 Note that all these transformations are correct if A is
5106 NaN, since the two alternatives (A and -A) are also NaNs. */
5107 if (!HONOR_SIGNED_ZEROS (TYPE_MODE (type))
5108 && (FLOAT_TYPE_P (TREE_TYPE (arg01))
5109 ? real_zerop (arg01)
5110 : integer_zerop (arg01))
5111 && ((TREE_CODE (arg2) == NEGATE_EXPR
5112 && operand_equal_p (TREE_OPERAND (arg2, 0), arg1, 0))
5113 /* In the case that A is of the form X-Y, '-A' (arg2) may
5114 have already been folded to Y-X, check for that. */
5115 || (TREE_CODE (arg1) == MINUS_EXPR
5116 && TREE_CODE (arg2) == MINUS_EXPR
5117 && operand_equal_p (TREE_OPERAND (arg1, 0),
5118 TREE_OPERAND (arg2, 1), 0)
5119 && operand_equal_p (TREE_OPERAND (arg1, 1),
5120 TREE_OPERAND (arg2, 0), 0))))
5125 tem = fold_convert (arg1_type, arg1);
5126 return pedantic_non_lvalue (fold_convert (type, negate_expr (tem)));
5129 return pedantic_non_lvalue (fold_convert (type, arg1));
5132 if (flag_trapping_math)
5137 if (TYPE_UNSIGNED (TREE_TYPE (arg1)))
5138 arg1 = fold_convert (signed_type_for
5139 (TREE_TYPE (arg1)), arg1);
5140 tem = fold_build1 (ABS_EXPR, TREE_TYPE (arg1), arg1);
5141 return pedantic_non_lvalue (fold_convert (type, tem));
5144 if (flag_trapping_math)
5148 if (TYPE_UNSIGNED (TREE_TYPE (arg1)))
5149 arg1 = fold_convert (signed_type_for
5150 (TREE_TYPE (arg1)), arg1);
5151 tem = fold_build1 (ABS_EXPR, TREE_TYPE (arg1), arg1);
5152 return negate_expr (fold_convert (type, tem));
5154 gcc_assert (TREE_CODE_CLASS (comp_code) == tcc_comparison);
5158 /* A != 0 ? A : 0 is simply A, unless A is -0. Likewise
5159 A == 0 ? A : 0 is always 0 unless A is -0. Note that
5160 both transformations are correct when A is NaN: A != 0
5161 is then true, and A == 0 is false. */
5163 if (!HONOR_SIGNED_ZEROS (TYPE_MODE (type))
5164 && integer_zerop (arg01) && integer_zerop (arg2))
5166 if (comp_code == NE_EXPR)
5167 return pedantic_non_lvalue (fold_convert (type, arg1));
5168 else if (comp_code == EQ_EXPR)
5169 return build_int_cst (type, 0);
5172 /* Try some transformations of A op B ? A : B.
5174 A == B? A : B same as B
5175 A != B? A : B same as A
5176 A >= B? A : B same as max (A, B)
5177 A > B? A : B same as max (B, A)
5178 A <= B? A : B same as min (A, B)
5179 A < B? A : B same as min (B, A)
5181 As above, these transformations don't work in the presence
5182 of signed zeros. For example, if A and B are zeros of
5183 opposite sign, the first two transformations will change
5184 the sign of the result. In the last four, the original
5185 expressions give different results for (A=+0, B=-0) and
5186 (A=-0, B=+0), but the transformed expressions do not.
5188 The first two transformations are correct if either A or B
5189 is a NaN. In the first transformation, the condition will
5190 be false, and B will indeed be chosen. In the case of the
5191 second transformation, the condition A != B will be true,
5192 and A will be chosen.
5194 The conversions to max() and min() are not correct if B is
5195 a number and A is not. The conditions in the original
5196 expressions will be false, so all four give B. The min()
5197 and max() versions would give a NaN instead. */
5198 if (!HONOR_SIGNED_ZEROS (TYPE_MODE (type))
5199 && operand_equal_for_comparison_p (arg01, arg2, arg00)
5200 /* Avoid these transformations if the COND_EXPR may be used
5201 as an lvalue in the C++ front-end. PR c++/19199. */
5203 || (strcmp (lang_hooks.name, "GNU C++") != 0
5204 && strcmp (lang_hooks.name, "GNU Objective-C++") != 0)
5205 || ! maybe_lvalue_p (arg1)
5206 || ! maybe_lvalue_p (arg2)))
5208 tree comp_op0 = arg00;
5209 tree comp_op1 = arg01;
5210 tree comp_type = TREE_TYPE (comp_op0);
5212 /* Avoid adding NOP_EXPRs in case this is an lvalue. */
5213 if (TYPE_MAIN_VARIANT (comp_type) == TYPE_MAIN_VARIANT (type))
5223 return pedantic_non_lvalue (fold_convert (type, arg2));
5225 return pedantic_non_lvalue (fold_convert (type, arg1));
5230 /* In C++ a ?: expression can be an lvalue, so put the
5231 operand which will be used if they are equal first
5232 so that we can convert this back to the
5233 corresponding COND_EXPR. */
5234 if (!HONOR_NANS (TYPE_MODE (TREE_TYPE (arg1))))
5236 comp_op0 = fold_convert (comp_type, comp_op0);
5237 comp_op1 = fold_convert (comp_type, comp_op1);
5238 tem = (comp_code == LE_EXPR || comp_code == UNLE_EXPR)
5239 ? fold_build2 (MIN_EXPR, comp_type, comp_op0, comp_op1)
5240 : fold_build2 (MIN_EXPR, comp_type, comp_op1, comp_op0);
5241 return pedantic_non_lvalue (fold_convert (type, tem));
5248 if (!HONOR_NANS (TYPE_MODE (TREE_TYPE (arg1))))
5250 comp_op0 = fold_convert (comp_type, comp_op0);
5251 comp_op1 = fold_convert (comp_type, comp_op1);
5252 tem = (comp_code == GE_EXPR || comp_code == UNGE_EXPR)
5253 ? fold_build2 (MAX_EXPR, comp_type, comp_op0, comp_op1)
5254 : fold_build2 (MAX_EXPR, comp_type, comp_op1, comp_op0);
5255 return pedantic_non_lvalue (fold_convert (type, tem));
5259 if (!HONOR_NANS (TYPE_MODE (TREE_TYPE (arg1))))
5260 return pedantic_non_lvalue (fold_convert (type, arg2));
5263 if (!HONOR_NANS (TYPE_MODE (TREE_TYPE (arg1))))
5264 return pedantic_non_lvalue (fold_convert (type, arg1));
5267 gcc_assert (TREE_CODE_CLASS (comp_code) == tcc_comparison);
5272 /* If this is A op C1 ? A : C2 with C1 and C2 constant integers,
5273 we might still be able to simplify this. For example,
5274 if C1 is one less or one more than C2, this might have started
5275 out as a MIN or MAX and been transformed by this function.
5276 Only good for INTEGER_TYPEs, because we need TYPE_MAX_VALUE. */
5278 if (INTEGRAL_TYPE_P (type)
5279 && TREE_CODE (arg01) == INTEGER_CST
5280 && TREE_CODE (arg2) == INTEGER_CST)
5284 /* We can replace A with C1 in this case. */
5285 arg1 = fold_convert (type, arg01);
5286 return fold_build3 (COND_EXPR, type, arg0, arg1, arg2);
5289 /* If C1 is C2 + 1, this is min(A, C2). */
5290 if (! operand_equal_p (arg2, TYPE_MAX_VALUE (type),
5292 && operand_equal_p (arg01,
5293 const_binop (PLUS_EXPR, arg2,
5294 build_int_cst (type, 1), 0),
5296 return pedantic_non_lvalue (fold_build2 (MIN_EXPR,
5298 fold_convert (type, arg1),
5303 /* If C1 is C2 - 1, this is min(A, C2). */
5304 if (! operand_equal_p (arg2, TYPE_MIN_VALUE (type),
5306 && operand_equal_p (arg01,
5307 const_binop (MINUS_EXPR, arg2,
5308 build_int_cst (type, 1), 0),
5310 return pedantic_non_lvalue (fold_build2 (MIN_EXPR,
5312 fold_convert (type, arg1),
5317 /* If C1 is C2 - 1, this is max(A, C2). */
5318 if (! operand_equal_p (arg2, TYPE_MIN_VALUE (type),
5320 && operand_equal_p (arg01,
5321 const_binop (MINUS_EXPR, arg2,
5322 build_int_cst (type, 1), 0),
5324 return pedantic_non_lvalue (fold_build2 (MAX_EXPR,
5326 fold_convert (type, arg1),
5331 /* If C1 is C2 + 1, this is max(A, C2). */
5332 if (! operand_equal_p (arg2, TYPE_MAX_VALUE (type),
5334 && operand_equal_p (arg01,
5335 const_binop (PLUS_EXPR, arg2,
5336 build_int_cst (type, 1), 0),
5338 return pedantic_non_lvalue (fold_build2 (MAX_EXPR,
5340 fold_convert (type, arg1),
5354 #ifndef LOGICAL_OP_NON_SHORT_CIRCUIT
5355 #define LOGICAL_OP_NON_SHORT_CIRCUIT \
5356 (BRANCH_COST (optimize_function_for_speed_p (cfun), \
5360 /* EXP is some logical combination of boolean tests. See if we can
5361 merge it into some range test. Return the new tree if so. */
5364 fold_range_test (enum tree_code code, tree type, tree op0, tree op1)
5366 int or_op = (code == TRUTH_ORIF_EXPR
5367 || code == TRUTH_OR_EXPR);
5368 int in0_p, in1_p, in_p;
5369 tree low0, low1, low, high0, high1, high;
5370 bool strict_overflow_p = false;
5371 tree lhs = make_range (op0, &in0_p, &low0, &high0, &strict_overflow_p);
5372 tree rhs = make_range (op1, &in1_p, &low1, &high1, &strict_overflow_p);
5374 const char * const warnmsg = G_("assuming signed overflow does not occur "
5375 "when simplifying range test");
5377 /* If this is an OR operation, invert both sides; we will invert
5378 again at the end. */
5380 in0_p = ! in0_p, in1_p = ! in1_p;
5382 /* If both expressions are the same, if we can merge the ranges, and we
5383 can build the range test, return it or it inverted. If one of the
5384 ranges is always true or always false, consider it to be the same
5385 expression as the other. */
5386 if ((lhs == 0 || rhs == 0 || operand_equal_p (lhs, rhs, 0))
5387 && merge_ranges (&in_p, &low, &high, in0_p, low0, high0,
5389 && 0 != (tem = (build_range_check (type,
5391 : rhs != 0 ? rhs : integer_zero_node,
5394 if (strict_overflow_p)
5395 fold_overflow_warning (warnmsg, WARN_STRICT_OVERFLOW_COMPARISON);
5396 return or_op ? invert_truthvalue (tem) : tem;
5399 /* On machines where the branch cost is expensive, if this is a
5400 short-circuited branch and the underlying object on both sides
5401 is the same, make a non-short-circuit operation. */
5402 else if (LOGICAL_OP_NON_SHORT_CIRCUIT
5403 && lhs != 0 && rhs != 0
5404 && (code == TRUTH_ANDIF_EXPR
5405 || code == TRUTH_ORIF_EXPR)
5406 && operand_equal_p (lhs, rhs, 0))
5408 /* If simple enough, just rewrite. Otherwise, make a SAVE_EXPR
5409 unless we are at top level or LHS contains a PLACEHOLDER_EXPR, in
5410 which cases we can't do this. */
5411 if (simple_operand_p (lhs))
5412 return build2 (code == TRUTH_ANDIF_EXPR
5413 ? TRUTH_AND_EXPR : TRUTH_OR_EXPR,
5416 else if (lang_hooks.decls.global_bindings_p () == 0
5417 && ! CONTAINS_PLACEHOLDER_P (lhs))
5419 tree common = save_expr (lhs);
5421 if (0 != (lhs = build_range_check (type, common,
5422 or_op ? ! in0_p : in0_p,
5424 && (0 != (rhs = build_range_check (type, common,
5425 or_op ? ! in1_p : in1_p,
5428 if (strict_overflow_p)
5429 fold_overflow_warning (warnmsg,
5430 WARN_STRICT_OVERFLOW_COMPARISON);
5431 return build2 (code == TRUTH_ANDIF_EXPR
5432 ? TRUTH_AND_EXPR : TRUTH_OR_EXPR,
5441 /* Subroutine for fold_truthop: C is an INTEGER_CST interpreted as a P
5442 bit value. Arrange things so the extra bits will be set to zero if and
5443 only if C is signed-extended to its full width. If MASK is nonzero,
5444 it is an INTEGER_CST that should be AND'ed with the extra bits. */
5447 unextend (tree c, int p, int unsignedp, tree mask)
5449 tree type = TREE_TYPE (c);
5450 int modesize = GET_MODE_BITSIZE (TYPE_MODE (type));
5453 if (p == modesize || unsignedp)
5456 /* We work by getting just the sign bit into the low-order bit, then
5457 into the high-order bit, then sign-extend. We then XOR that value
5459 temp = const_binop (RSHIFT_EXPR, c, size_int (p - 1), 0);
5460 temp = const_binop (BIT_AND_EXPR, temp, size_int (1), 0);
5462 /* We must use a signed type in order to get an arithmetic right shift.
5463 However, we must also avoid introducing accidental overflows, so that
5464 a subsequent call to integer_zerop will work. Hence we must
5465 do the type conversion here. At this point, the constant is either
5466 zero or one, and the conversion to a signed type can never overflow.
5467 We could get an overflow if this conversion is done anywhere else. */
5468 if (TYPE_UNSIGNED (type))
5469 temp = fold_convert (signed_type_for (type), temp);
5471 temp = const_binop (LSHIFT_EXPR, temp, size_int (modesize - 1), 0);
5472 temp = const_binop (RSHIFT_EXPR, temp, size_int (modesize - p - 1), 0);
5474 temp = const_binop (BIT_AND_EXPR, temp,
5475 fold_convert (TREE_TYPE (c), mask), 0);
5476 /* If necessary, convert the type back to match the type of C. */
5477 if (TYPE_UNSIGNED (type))
5478 temp = fold_convert (type, temp);
5480 return fold_convert (type, const_binop (BIT_XOR_EXPR, c, temp, 0));
5483 /* Find ways of folding logical expressions of LHS and RHS:
5484 Try to merge two comparisons to the same innermost item.
5485 Look for range tests like "ch >= '0' && ch <= '9'".
5486 Look for combinations of simple terms on machines with expensive branches
5487 and evaluate the RHS unconditionally.
5489 For example, if we have p->a == 2 && p->b == 4 and we can make an
5490 object large enough to span both A and B, we can do this with a comparison
5491 against the object ANDed with the a mask.
5493 If we have p->a == q->a && p->b == q->b, we may be able to use bit masking
5494 operations to do this with one comparison.
5496 We check for both normal comparisons and the BIT_AND_EXPRs made this by
5497 function and the one above.
5499 CODE is the logical operation being done. It can be TRUTH_ANDIF_EXPR,
5500 TRUTH_AND_EXPR, TRUTH_ORIF_EXPR, or TRUTH_OR_EXPR.
5502 TRUTH_TYPE is the type of the logical operand and LHS and RHS are its
5505 We return the simplified tree or 0 if no optimization is possible. */
5508 fold_truthop (enum tree_code code, tree truth_type, tree lhs, tree rhs)
5510 /* If this is the "or" of two comparisons, we can do something if
5511 the comparisons are NE_EXPR. If this is the "and", we can do something
5512 if the comparisons are EQ_EXPR. I.e.,
5513 (a->b == 2 && a->c == 4) can become (a->new == NEW).
5515 WANTED_CODE is this operation code. For single bit fields, we can
5516 convert EQ_EXPR to NE_EXPR so we need not reject the "wrong"
5517 comparison for one-bit fields. */
5519 enum tree_code wanted_code;
5520 enum tree_code lcode, rcode;
5521 tree ll_arg, lr_arg, rl_arg, rr_arg;
5522 tree ll_inner, lr_inner, rl_inner, rr_inner;
5523 HOST_WIDE_INT ll_bitsize, ll_bitpos, lr_bitsize, lr_bitpos;
5524 HOST_WIDE_INT rl_bitsize, rl_bitpos, rr_bitsize, rr_bitpos;
5525 HOST_WIDE_INT xll_bitpos, xlr_bitpos, xrl_bitpos, xrr_bitpos;
5526 HOST_WIDE_INT lnbitsize, lnbitpos, rnbitsize, rnbitpos;
5527 int ll_unsignedp, lr_unsignedp, rl_unsignedp, rr_unsignedp;
5528 enum machine_mode ll_mode, lr_mode, rl_mode, rr_mode;
5529 enum machine_mode lnmode, rnmode;
5530 tree ll_mask, lr_mask, rl_mask, rr_mask;
5531 tree ll_and_mask, lr_and_mask, rl_and_mask, rr_and_mask;
5532 tree l_const, r_const;
5533 tree lntype, rntype, result;
5534 HOST_WIDE_INT first_bit, end_bit;
5536 tree orig_lhs = lhs, orig_rhs = rhs;
5537 enum tree_code orig_code = code;
5539 /* Start by getting the comparison codes. Fail if anything is volatile.
5540 If one operand is a BIT_AND_EXPR with the constant one, treat it as if
5541 it were surrounded with a NE_EXPR. */
5543 if (TREE_SIDE_EFFECTS (lhs) || TREE_SIDE_EFFECTS (rhs))
5546 lcode = TREE_CODE (lhs);
5547 rcode = TREE_CODE (rhs);
5549 if (lcode == BIT_AND_EXPR && integer_onep (TREE_OPERAND (lhs, 1)))
5551 lhs = build2 (NE_EXPR, truth_type, lhs,
5552 build_int_cst (TREE_TYPE (lhs), 0));
5556 if (rcode == BIT_AND_EXPR && integer_onep (TREE_OPERAND (rhs, 1)))
5558 rhs = build2 (NE_EXPR, truth_type, rhs,
5559 build_int_cst (TREE_TYPE (rhs), 0));
5563 if (TREE_CODE_CLASS (lcode) != tcc_comparison
5564 || TREE_CODE_CLASS (rcode) != tcc_comparison)
5567 ll_arg = TREE_OPERAND (lhs, 0);
5568 lr_arg = TREE_OPERAND (lhs, 1);
5569 rl_arg = TREE_OPERAND (rhs, 0);
5570 rr_arg = TREE_OPERAND (rhs, 1);
5572 /* Simplify (x<y) && (x==y) into (x<=y) and related optimizations. */
5573 if (simple_operand_p (ll_arg)
5574 && simple_operand_p (lr_arg))
5577 if (operand_equal_p (ll_arg, rl_arg, 0)
5578 && operand_equal_p (lr_arg, rr_arg, 0))
5580 result = combine_comparisons (code, lcode, rcode,
5581 truth_type, ll_arg, lr_arg);
5585 else if (operand_equal_p (ll_arg, rr_arg, 0)
5586 && operand_equal_p (lr_arg, rl_arg, 0))
5588 result = combine_comparisons (code, lcode,
5589 swap_tree_comparison (rcode),
5590 truth_type, ll_arg, lr_arg);
5596 code = ((code == TRUTH_AND_EXPR || code == TRUTH_ANDIF_EXPR)
5597 ? TRUTH_AND_EXPR : TRUTH_OR_EXPR);
5599 /* If the RHS can be evaluated unconditionally and its operands are
5600 simple, it wins to evaluate the RHS unconditionally on machines
5601 with expensive branches. In this case, this isn't a comparison
5602 that can be merged. Avoid doing this if the RHS is a floating-point
5603 comparison since those can trap. */
5605 if (BRANCH_COST (optimize_function_for_speed_p (cfun),
5607 && ! FLOAT_TYPE_P (TREE_TYPE (rl_arg))
5608 && simple_operand_p (rl_arg)
5609 && simple_operand_p (rr_arg))
5611 /* Convert (a != 0) || (b != 0) into (a | b) != 0. */
5612 if (code == TRUTH_OR_EXPR
5613 && lcode == NE_EXPR && integer_zerop (lr_arg)
5614 && rcode == NE_EXPR && integer_zerop (rr_arg)
5615 && TREE_TYPE (ll_arg) == TREE_TYPE (rl_arg)
5616 && INTEGRAL_TYPE_P (TREE_TYPE (ll_arg)))
5617 return build2 (NE_EXPR, truth_type,
5618 build2 (BIT_IOR_EXPR, TREE_TYPE (ll_arg),
5620 build_int_cst (TREE_TYPE (ll_arg), 0));
5622 /* Convert (a == 0) && (b == 0) into (a | b) == 0. */
5623 if (code == TRUTH_AND_EXPR
5624 && lcode == EQ_EXPR && integer_zerop (lr_arg)
5625 && rcode == EQ_EXPR && integer_zerop (rr_arg)
5626 && TREE_TYPE (ll_arg) == TREE_TYPE (rl_arg)
5627 && INTEGRAL_TYPE_P (TREE_TYPE (ll_arg)))
5628 return build2 (EQ_EXPR, truth_type,
5629 build2 (BIT_IOR_EXPR, TREE_TYPE (ll_arg),
5631 build_int_cst (TREE_TYPE (ll_arg), 0));
5633 if (LOGICAL_OP_NON_SHORT_CIRCUIT)
5635 if (code != orig_code || lhs != orig_lhs || rhs != orig_rhs)
5636 return build2 (code, truth_type, lhs, rhs);
5641 /* See if the comparisons can be merged. Then get all the parameters for
5644 if ((lcode != EQ_EXPR && lcode != NE_EXPR)
5645 || (rcode != EQ_EXPR && rcode != NE_EXPR))
5649 ll_inner = decode_field_reference (ll_arg,
5650 &ll_bitsize, &ll_bitpos, &ll_mode,
5651 &ll_unsignedp, &volatilep, &ll_mask,
5653 lr_inner = decode_field_reference (lr_arg,
5654 &lr_bitsize, &lr_bitpos, &lr_mode,
5655 &lr_unsignedp, &volatilep, &lr_mask,
5657 rl_inner = decode_field_reference (rl_arg,
5658 &rl_bitsize, &rl_bitpos, &rl_mode,
5659 &rl_unsignedp, &volatilep, &rl_mask,
5661 rr_inner = decode_field_reference (rr_arg,
5662 &rr_bitsize, &rr_bitpos, &rr_mode,
5663 &rr_unsignedp, &volatilep, &rr_mask,
5666 /* It must be true that the inner operation on the lhs of each
5667 comparison must be the same if we are to be able to do anything.
5668 Then see if we have constants. If not, the same must be true for
5670 if (volatilep || ll_inner == 0 || rl_inner == 0
5671 || ! operand_equal_p (ll_inner, rl_inner, 0))
5674 if (TREE_CODE (lr_arg) == INTEGER_CST
5675 && TREE_CODE (rr_arg) == INTEGER_CST)
5676 l_const = lr_arg, r_const = rr_arg;
5677 else if (lr_inner == 0 || rr_inner == 0
5678 || ! operand_equal_p (lr_inner, rr_inner, 0))
5681 l_const = r_const = 0;
5683 /* If either comparison code is not correct for our logical operation,
5684 fail. However, we can convert a one-bit comparison against zero into
5685 the opposite comparison against that bit being set in the field. */
5687 wanted_code = (code == TRUTH_AND_EXPR ? EQ_EXPR : NE_EXPR);
5688 if (lcode != wanted_code)
5690 if (l_const && integer_zerop (l_const) && integer_pow2p (ll_mask))
5692 /* Make the left operand unsigned, since we are only interested
5693 in the value of one bit. Otherwise we are doing the wrong
5702 /* This is analogous to the code for l_const above. */
5703 if (rcode != wanted_code)
5705 if (r_const && integer_zerop (r_const) && integer_pow2p (rl_mask))
5714 /* See if we can find a mode that contains both fields being compared on
5715 the left. If we can't, fail. Otherwise, update all constants and masks
5716 to be relative to a field of that size. */
5717 first_bit = MIN (ll_bitpos, rl_bitpos);
5718 end_bit = MAX (ll_bitpos + ll_bitsize, rl_bitpos + rl_bitsize);
5719 lnmode = get_best_mode (end_bit - first_bit, first_bit,
5720 TYPE_ALIGN (TREE_TYPE (ll_inner)), word_mode,
5722 if (lnmode == VOIDmode)
5725 lnbitsize = GET_MODE_BITSIZE (lnmode);
5726 lnbitpos = first_bit & ~ (lnbitsize - 1);
5727 lntype = lang_hooks.types.type_for_size (lnbitsize, 1);
5728 xll_bitpos = ll_bitpos - lnbitpos, xrl_bitpos = rl_bitpos - lnbitpos;
5730 if (BYTES_BIG_ENDIAN)
5732 xll_bitpos = lnbitsize - xll_bitpos - ll_bitsize;
5733 xrl_bitpos = lnbitsize - xrl_bitpos - rl_bitsize;
5736 ll_mask = const_binop (LSHIFT_EXPR, fold_convert (lntype, ll_mask),
5737 size_int (xll_bitpos), 0);
5738 rl_mask = const_binop (LSHIFT_EXPR, fold_convert (lntype, rl_mask),
5739 size_int (xrl_bitpos), 0);
5743 l_const = fold_convert (lntype, l_const);
5744 l_const = unextend (l_const, ll_bitsize, ll_unsignedp, ll_and_mask);
5745 l_const = const_binop (LSHIFT_EXPR, l_const, size_int (xll_bitpos), 0);
5746 if (! integer_zerop (const_binop (BIT_AND_EXPR, l_const,
5747 fold_build1 (BIT_NOT_EXPR,
5751 warning (0, "comparison is always %d", wanted_code == NE_EXPR);
5753 return constant_boolean_node (wanted_code == NE_EXPR, truth_type);
5758 r_const = fold_convert (lntype, r_const);
5759 r_const = unextend (r_const, rl_bitsize, rl_unsignedp, rl_and_mask);
5760 r_const = const_binop (LSHIFT_EXPR, r_const, size_int (xrl_bitpos), 0);
5761 if (! integer_zerop (const_binop (BIT_AND_EXPR, r_const,
5762 fold_build1 (BIT_NOT_EXPR,
5766 warning (0, "comparison is always %d", wanted_code == NE_EXPR);
5768 return constant_boolean_node (wanted_code == NE_EXPR, truth_type);
5772 /* If the right sides are not constant, do the same for it. Also,
5773 disallow this optimization if a size or signedness mismatch occurs
5774 between the left and right sides. */
5777 if (ll_bitsize != lr_bitsize || rl_bitsize != rr_bitsize
5778 || ll_unsignedp != lr_unsignedp || rl_unsignedp != rr_unsignedp
5779 /* Make sure the two fields on the right
5780 correspond to the left without being swapped. */
5781 || ll_bitpos - rl_bitpos != lr_bitpos - rr_bitpos)
5784 first_bit = MIN (lr_bitpos, rr_bitpos);
5785 end_bit = MAX (lr_bitpos + lr_bitsize, rr_bitpos + rr_bitsize);
5786 rnmode = get_best_mode (end_bit - first_bit, first_bit,
5787 TYPE_ALIGN (TREE_TYPE (lr_inner)), word_mode,
5789 if (rnmode == VOIDmode)
5792 rnbitsize = GET_MODE_BITSIZE (rnmode);
5793 rnbitpos = first_bit & ~ (rnbitsize - 1);
5794 rntype = lang_hooks.types.type_for_size (rnbitsize, 1);
5795 xlr_bitpos = lr_bitpos - rnbitpos, xrr_bitpos = rr_bitpos - rnbitpos;
5797 if (BYTES_BIG_ENDIAN)
5799 xlr_bitpos = rnbitsize - xlr_bitpos - lr_bitsize;
5800 xrr_bitpos = rnbitsize - xrr_bitpos - rr_bitsize;
5803 lr_mask = const_binop (LSHIFT_EXPR, fold_convert (rntype, lr_mask),
5804 size_int (xlr_bitpos), 0);
5805 rr_mask = const_binop (LSHIFT_EXPR, fold_convert (rntype, rr_mask),
5806 size_int (xrr_bitpos), 0);
5808 /* Make a mask that corresponds to both fields being compared.
5809 Do this for both items being compared. If the operands are the
5810 same size and the bits being compared are in the same position
5811 then we can do this by masking both and comparing the masked
5813 ll_mask = const_binop (BIT_IOR_EXPR, ll_mask, rl_mask, 0);
5814 lr_mask = const_binop (BIT_IOR_EXPR, lr_mask, rr_mask, 0);
5815 if (lnbitsize == rnbitsize && xll_bitpos == xlr_bitpos)
5817 lhs = make_bit_field_ref (ll_inner, lntype, lnbitsize, lnbitpos,
5818 ll_unsignedp || rl_unsignedp);
5819 if (! all_ones_mask_p (ll_mask, lnbitsize))
5820 lhs = build2 (BIT_AND_EXPR, lntype, lhs, ll_mask);
5822 rhs = make_bit_field_ref (lr_inner, rntype, rnbitsize, rnbitpos,
5823 lr_unsignedp || rr_unsignedp);
5824 if (! all_ones_mask_p (lr_mask, rnbitsize))
5825 rhs = build2 (BIT_AND_EXPR, rntype, rhs, lr_mask);
5827 return build2 (wanted_code, truth_type, lhs, rhs);
5830 /* There is still another way we can do something: If both pairs of
5831 fields being compared are adjacent, we may be able to make a wider
5832 field containing them both.
5834 Note that we still must mask the lhs/rhs expressions. Furthermore,
5835 the mask must be shifted to account for the shift done by
5836 make_bit_field_ref. */
5837 if ((ll_bitsize + ll_bitpos == rl_bitpos
5838 && lr_bitsize + lr_bitpos == rr_bitpos)
5839 || (ll_bitpos == rl_bitpos + rl_bitsize
5840 && lr_bitpos == rr_bitpos + rr_bitsize))
5844 lhs = make_bit_field_ref (ll_inner, lntype, ll_bitsize + rl_bitsize,
5845 MIN (ll_bitpos, rl_bitpos), ll_unsignedp);
5846 rhs = make_bit_field_ref (lr_inner, rntype, lr_bitsize + rr_bitsize,
5847 MIN (lr_bitpos, rr_bitpos), lr_unsignedp);
5849 ll_mask = const_binop (RSHIFT_EXPR, ll_mask,
5850 size_int (MIN (xll_bitpos, xrl_bitpos)), 0);
5851 lr_mask = const_binop (RSHIFT_EXPR, lr_mask,
5852 size_int (MIN (xlr_bitpos, xrr_bitpos)), 0);
5854 /* Convert to the smaller type before masking out unwanted bits. */
5856 if (lntype != rntype)
5858 if (lnbitsize > rnbitsize)
5860 lhs = fold_convert (rntype, lhs);
5861 ll_mask = fold_convert (rntype, ll_mask);
5864 else if (lnbitsize < rnbitsize)
5866 rhs = fold_convert (lntype, rhs);
5867 lr_mask = fold_convert (lntype, lr_mask);
5872 if (! all_ones_mask_p (ll_mask, ll_bitsize + rl_bitsize))
5873 lhs = build2 (BIT_AND_EXPR, type, lhs, ll_mask);
5875 if (! all_ones_mask_p (lr_mask, lr_bitsize + rr_bitsize))
5876 rhs = build2 (BIT_AND_EXPR, type, rhs, lr_mask);
5878 return build2 (wanted_code, truth_type, lhs, rhs);
5884 /* Handle the case of comparisons with constants. If there is something in
5885 common between the masks, those bits of the constants must be the same.
5886 If not, the condition is always false. Test for this to avoid generating
5887 incorrect code below. */
5888 result = const_binop (BIT_AND_EXPR, ll_mask, rl_mask, 0);
5889 if (! integer_zerop (result)
5890 && simple_cst_equal (const_binop (BIT_AND_EXPR, result, l_const, 0),
5891 const_binop (BIT_AND_EXPR, result, r_const, 0)) != 1)
5893 if (wanted_code == NE_EXPR)
5895 warning (0, "%<or%> of unmatched not-equal tests is always 1");
5896 return constant_boolean_node (true, truth_type);
5900 warning (0, "%<and%> of mutually exclusive equal-tests is always 0");
5901 return constant_boolean_node (false, truth_type);
5905 /* Construct the expression we will return. First get the component
5906 reference we will make. Unless the mask is all ones the width of
5907 that field, perform the mask operation. Then compare with the
5909 result = make_bit_field_ref (ll_inner, lntype, lnbitsize, lnbitpos,
5910 ll_unsignedp || rl_unsignedp);
5912 ll_mask = const_binop (BIT_IOR_EXPR, ll_mask, rl_mask, 0);
5913 if (! all_ones_mask_p (ll_mask, lnbitsize))
5914 result = build2 (BIT_AND_EXPR, lntype, result, ll_mask);
5916 return build2 (wanted_code, truth_type, result,
5917 const_binop (BIT_IOR_EXPR, l_const, r_const, 0));
5920 /* Optimize T, which is a comparison of a MIN_EXPR or MAX_EXPR with a
5924 optimize_minmax_comparison (enum tree_code code, tree type, tree op0, tree op1)
5927 enum tree_code op_code;
5930 int consts_equal, consts_lt;
5933 STRIP_SIGN_NOPS (arg0);
5935 op_code = TREE_CODE (arg0);
5936 minmax_const = TREE_OPERAND (arg0, 1);
5937 comp_const = fold_convert (TREE_TYPE (arg0), op1);
5938 consts_equal = tree_int_cst_equal (minmax_const, comp_const);
5939 consts_lt = tree_int_cst_lt (minmax_const, comp_const);
5940 inner = TREE_OPERAND (arg0, 0);
5942 /* If something does not permit us to optimize, return the original tree. */
5943 if ((op_code != MIN_EXPR && op_code != MAX_EXPR)
5944 || TREE_CODE (comp_const) != INTEGER_CST
5945 || TREE_OVERFLOW (comp_const)
5946 || TREE_CODE (minmax_const) != INTEGER_CST
5947 || TREE_OVERFLOW (minmax_const))
5950 /* Now handle all the various comparison codes. We only handle EQ_EXPR
5951 and GT_EXPR, doing the rest with recursive calls using logical
5955 case NE_EXPR: case LT_EXPR: case LE_EXPR:
5957 tree tem = optimize_minmax_comparison (invert_tree_comparison (code, false),
5960 return invert_truthvalue (tem);
5966 fold_build2 (TRUTH_ORIF_EXPR, type,
5967 optimize_minmax_comparison
5968 (EQ_EXPR, type, arg0, comp_const),
5969 optimize_minmax_comparison
5970 (GT_EXPR, type, arg0, comp_const));
5973 if (op_code == MAX_EXPR && consts_equal)
5974 /* MAX (X, 0) == 0 -> X <= 0 */
5975 return fold_build2 (LE_EXPR, type, inner, comp_const);
5977 else if (op_code == MAX_EXPR && consts_lt)
5978 /* MAX (X, 0) == 5 -> X == 5 */
5979 return fold_build2 (EQ_EXPR, type, inner, comp_const);
5981 else if (op_code == MAX_EXPR)
5982 /* MAX (X, 0) == -1 -> false */
5983 return omit_one_operand (type, integer_zero_node, inner);
5985 else if (consts_equal)
5986 /* MIN (X, 0) == 0 -> X >= 0 */
5987 return fold_build2 (GE_EXPR, type, inner, comp_const);
5990 /* MIN (X, 0) == 5 -> false */
5991 return omit_one_operand (type, integer_zero_node, inner);
5994 /* MIN (X, 0) == -1 -> X == -1 */
5995 return fold_build2 (EQ_EXPR, type, inner, comp_const);
5998 if (op_code == MAX_EXPR && (consts_equal || consts_lt))
5999 /* MAX (X, 0) > 0 -> X > 0
6000 MAX (X, 0) > 5 -> X > 5 */
6001 return fold_build2 (GT_EXPR, type, inner, comp_const);
6003 else if (op_code == MAX_EXPR)
6004 /* MAX (X, 0) > -1 -> true */
6005 return omit_one_operand (type, integer_one_node, inner);
6007 else if (op_code == MIN_EXPR && (consts_equal || consts_lt))
6008 /* MIN (X, 0) > 0 -> false
6009 MIN (X, 0) > 5 -> false */
6010 return omit_one_operand (type, integer_zero_node, inner);
6013 /* MIN (X, 0) > -1 -> X > -1 */
6014 return fold_build2 (GT_EXPR, type, inner, comp_const);
6021 /* T is an integer expression that is being multiplied, divided, or taken a
6022 modulus (CODE says which and what kind of divide or modulus) by a
6023 constant C. See if we can eliminate that operation by folding it with
6024 other operations already in T. WIDE_TYPE, if non-null, is a type that
6025 should be used for the computation if wider than our type.
6027 For example, if we are dividing (X * 8) + (Y * 16) by 4, we can return
6028 (X * 2) + (Y * 4). We must, however, be assured that either the original
6029 expression would not overflow or that overflow is undefined for the type
6030 in the language in question.
6032 If we return a non-null expression, it is an equivalent form of the
6033 original computation, but need not be in the original type.
6035 We set *STRICT_OVERFLOW_P to true if the return values depends on
6036 signed overflow being undefined. Otherwise we do not change
6037 *STRICT_OVERFLOW_P. */
6040 extract_muldiv (tree t, tree c, enum tree_code code, tree wide_type,
6041 bool *strict_overflow_p)
6043 /* To avoid exponential search depth, refuse to allow recursion past
6044 three levels. Beyond that (1) it's highly unlikely that we'll find
6045 something interesting and (2) we've probably processed it before
6046 when we built the inner expression. */
6055 ret = extract_muldiv_1 (t, c, code, wide_type, strict_overflow_p);
6062 extract_muldiv_1 (tree t, tree c, enum tree_code code, tree wide_type,
6063 bool *strict_overflow_p)
6065 tree type = TREE_TYPE (t);
6066 enum tree_code tcode = TREE_CODE (t);
6067 tree ctype = (wide_type != 0 && (GET_MODE_SIZE (TYPE_MODE (wide_type))
6068 > GET_MODE_SIZE (TYPE_MODE (type)))
6069 ? wide_type : type);
6071 int same_p = tcode == code;
6072 tree op0 = NULL_TREE, op1 = NULL_TREE;
6073 bool sub_strict_overflow_p;
6075 /* Don't deal with constants of zero here; they confuse the code below. */
6076 if (integer_zerop (c))
6079 if (TREE_CODE_CLASS (tcode) == tcc_unary)
6080 op0 = TREE_OPERAND (t, 0);
6082 if (TREE_CODE_CLASS (tcode) == tcc_binary)
6083 op0 = TREE_OPERAND (t, 0), op1 = TREE_OPERAND (t, 1);
6085 /* Note that we need not handle conditional operations here since fold
6086 already handles those cases. So just do arithmetic here. */
6090 /* For a constant, we can always simplify if we are a multiply
6091 or (for divide and modulus) if it is a multiple of our constant. */
6092 if (code == MULT_EXPR
6093 || integer_zerop (const_binop (TRUNC_MOD_EXPR, t, c, 0)))
6094 return const_binop (code, fold_convert (ctype, t),
6095 fold_convert (ctype, c), 0);
6098 CASE_CONVERT: case NON_LVALUE_EXPR:
6099 /* If op0 is an expression ... */
6100 if ((COMPARISON_CLASS_P (op0)
6101 || UNARY_CLASS_P (op0)
6102 || BINARY_CLASS_P (op0)
6103 || VL_EXP_CLASS_P (op0)
6104 || EXPRESSION_CLASS_P (op0))
6105 /* ... and has wrapping overflow, and its type is smaller
6106 than ctype, then we cannot pass through as widening. */
6107 && ((TYPE_OVERFLOW_WRAPS (TREE_TYPE (op0))
6108 && ! (TREE_CODE (TREE_TYPE (op0)) == INTEGER_TYPE
6109 && TYPE_IS_SIZETYPE (TREE_TYPE (op0)))
6110 && (TYPE_PRECISION (ctype)
6111 > TYPE_PRECISION (TREE_TYPE (op0))))
6112 /* ... or this is a truncation (t is narrower than op0),
6113 then we cannot pass through this narrowing. */
6114 || (TYPE_PRECISION (type)
6115 < TYPE_PRECISION (TREE_TYPE (op0)))
6116 /* ... or signedness changes for division or modulus,
6117 then we cannot pass through this conversion. */
6118 || (code != MULT_EXPR
6119 && (TYPE_UNSIGNED (ctype)
6120 != TYPE_UNSIGNED (TREE_TYPE (op0))))
6121 /* ... or has undefined overflow while the converted to
6122 type has not, we cannot do the operation in the inner type
6123 as that would introduce undefined overflow. */
6124 || (TYPE_OVERFLOW_UNDEFINED (TREE_TYPE (op0))
6125 && !TYPE_OVERFLOW_UNDEFINED (type))))
6128 /* Pass the constant down and see if we can make a simplification. If
6129 we can, replace this expression with the inner simplification for
6130 possible later conversion to our or some other type. */
6131 if ((t2 = fold_convert (TREE_TYPE (op0), c)) != 0
6132 && TREE_CODE (t2) == INTEGER_CST
6133 && !TREE_OVERFLOW (t2)
6134 && (0 != (t1 = extract_muldiv (op0, t2, code,
6136 ? ctype : NULL_TREE,
6137 strict_overflow_p))))
6142 /* If widening the type changes it from signed to unsigned, then we
6143 must avoid building ABS_EXPR itself as unsigned. */
6144 if (TYPE_UNSIGNED (ctype) && !TYPE_UNSIGNED (type))
6146 tree cstype = (*signed_type_for) (ctype);
6147 if ((t1 = extract_muldiv (op0, c, code, cstype, strict_overflow_p))
6150 t1 = fold_build1 (tcode, cstype, fold_convert (cstype, t1));
6151 return fold_convert (ctype, t1);
6155 /* If the constant is negative, we cannot simplify this. */
6156 if (tree_int_cst_sgn (c) == -1)
6160 if ((t1 = extract_muldiv (op0, c, code, wide_type, strict_overflow_p))
6162 return fold_build1 (tcode, ctype, fold_convert (ctype, t1));
6165 case MIN_EXPR: case MAX_EXPR:
6166 /* If widening the type changes the signedness, then we can't perform
6167 this optimization as that changes the result. */
6168 if (TYPE_UNSIGNED (ctype) != TYPE_UNSIGNED (type))
6171 /* MIN (a, b) / 5 -> MIN (a / 5, b / 5) */
6172 sub_strict_overflow_p = false;
6173 if ((t1 = extract_muldiv (op0, c, code, wide_type,
6174 &sub_strict_overflow_p)) != 0
6175 && (t2 = extract_muldiv (op1, c, code, wide_type,
6176 &sub_strict_overflow_p)) != 0)
6178 if (tree_int_cst_sgn (c) < 0)
6179 tcode = (tcode == MIN_EXPR ? MAX_EXPR : MIN_EXPR);
6180 if (sub_strict_overflow_p)
6181 *strict_overflow_p = true;
6182 return fold_build2 (tcode, ctype, fold_convert (ctype, t1),
6183 fold_convert (ctype, t2));
6187 case LSHIFT_EXPR: case RSHIFT_EXPR:
6188 /* If the second operand is constant, this is a multiplication
6189 or floor division, by a power of two, so we can treat it that
6190 way unless the multiplier or divisor overflows. Signed
6191 left-shift overflow is implementation-defined rather than
6192 undefined in C90, so do not convert signed left shift into
6194 if (TREE_CODE (op1) == INTEGER_CST
6195 && (tcode == RSHIFT_EXPR || TYPE_UNSIGNED (TREE_TYPE (op0)))
6196 /* const_binop may not detect overflow correctly,
6197 so check for it explicitly here. */
6198 && TYPE_PRECISION (TREE_TYPE (size_one_node)) > TREE_INT_CST_LOW (op1)
6199 && TREE_INT_CST_HIGH (op1) == 0
6200 && 0 != (t1 = fold_convert (ctype,
6201 const_binop (LSHIFT_EXPR,
6204 && !TREE_OVERFLOW (t1))
6205 return extract_muldiv (build2 (tcode == LSHIFT_EXPR
6206 ? MULT_EXPR : FLOOR_DIV_EXPR,
6207 ctype, fold_convert (ctype, op0), t1),
6208 c, code, wide_type, strict_overflow_p);
6211 case PLUS_EXPR: case MINUS_EXPR:
6212 /* See if we can eliminate the operation on both sides. If we can, we
6213 can return a new PLUS or MINUS. If we can't, the only remaining
6214 cases where we can do anything are if the second operand is a
6216 sub_strict_overflow_p = false;
6217 t1 = extract_muldiv (op0, c, code, wide_type, &sub_strict_overflow_p);
6218 t2 = extract_muldiv (op1, c, code, wide_type, &sub_strict_overflow_p);
6219 if (t1 != 0 && t2 != 0
6220 && (code == MULT_EXPR
6221 /* If not multiplication, we can only do this if both operands
6222 are divisible by c. */
6223 || (multiple_of_p (ctype, op0, c)
6224 && multiple_of_p (ctype, op1, c))))
6226 if (sub_strict_overflow_p)
6227 *strict_overflow_p = true;
6228 return fold_build2 (tcode, ctype, fold_convert (ctype, t1),
6229 fold_convert (ctype, t2));
6232 /* If this was a subtraction, negate OP1 and set it to be an addition.
6233 This simplifies the logic below. */
6234 if (tcode == MINUS_EXPR)
6235 tcode = PLUS_EXPR, op1 = negate_expr (op1);
6237 if (TREE_CODE (op1) != INTEGER_CST)
6240 /* If either OP1 or C are negative, this optimization is not safe for
6241 some of the division and remainder types while for others we need
6242 to change the code. */
6243 if (tree_int_cst_sgn (op1) < 0 || tree_int_cst_sgn (c) < 0)
6245 if (code == CEIL_DIV_EXPR)
6246 code = FLOOR_DIV_EXPR;
6247 else if (code == FLOOR_DIV_EXPR)
6248 code = CEIL_DIV_EXPR;
6249 else if (code != MULT_EXPR
6250 && code != CEIL_MOD_EXPR && code != FLOOR_MOD_EXPR)
6254 /* If it's a multiply or a division/modulus operation of a multiple
6255 of our constant, do the operation and verify it doesn't overflow. */
6256 if (code == MULT_EXPR
6257 || integer_zerop (const_binop (TRUNC_MOD_EXPR, op1, c, 0)))
6259 op1 = const_binop (code, fold_convert (ctype, op1),
6260 fold_convert (ctype, c), 0);
6261 /* We allow the constant to overflow with wrapping semantics. */
6263 || (TREE_OVERFLOW (op1) && !TYPE_OVERFLOW_WRAPS (ctype)))
6269 /* If we have an unsigned type is not a sizetype, we cannot widen
6270 the operation since it will change the result if the original
6271 computation overflowed. */
6272 if (TYPE_UNSIGNED (ctype)
6273 && ! (TREE_CODE (ctype) == INTEGER_TYPE && TYPE_IS_SIZETYPE (ctype))
6277 /* If we were able to eliminate our operation from the first side,
6278 apply our operation to the second side and reform the PLUS. */
6279 if (t1 != 0 && (TREE_CODE (t1) != code || code == MULT_EXPR))
6280 return fold_build2 (tcode, ctype, fold_convert (ctype, t1), op1);
6282 /* The last case is if we are a multiply. In that case, we can
6283 apply the distributive law to commute the multiply and addition
6284 if the multiplication of the constants doesn't overflow. */
6285 if (code == MULT_EXPR)
6286 return fold_build2 (tcode, ctype,
6287 fold_build2 (code, ctype,
6288 fold_convert (ctype, op0),
6289 fold_convert (ctype, c)),
6295 /* We have a special case here if we are doing something like
6296 (C * 8) % 4 since we know that's zero. */
6297 if ((code == TRUNC_MOD_EXPR || code == CEIL_MOD_EXPR
6298 || code == FLOOR_MOD_EXPR || code == ROUND_MOD_EXPR)
6299 /* If the multiplication can overflow we cannot optimize this.
6300 ??? Until we can properly mark individual operations as
6301 not overflowing we need to treat sizetype special here as
6302 stor-layout relies on this opimization to make
6303 DECL_FIELD_BIT_OFFSET always a constant. */
6304 && (TYPE_OVERFLOW_UNDEFINED (TREE_TYPE (t))
6305 || (TREE_CODE (TREE_TYPE (t)) == INTEGER_TYPE
6306 && TYPE_IS_SIZETYPE (TREE_TYPE (t))))
6307 && TREE_CODE (TREE_OPERAND (t, 1)) == INTEGER_CST
6308 && integer_zerop (const_binop (TRUNC_MOD_EXPR, op1, c, 0)))
6310 *strict_overflow_p = true;
6311 return omit_one_operand (type, integer_zero_node, op0);
6314 /* ... fall through ... */
6316 case TRUNC_DIV_EXPR: case CEIL_DIV_EXPR: case FLOOR_DIV_EXPR:
6317 case ROUND_DIV_EXPR: case EXACT_DIV_EXPR:
6318 /* If we can extract our operation from the LHS, do so and return a
6319 new operation. Likewise for the RHS from a MULT_EXPR. Otherwise,
6320 do something only if the second operand is a constant. */
6322 && (t1 = extract_muldiv (op0, c, code, wide_type,
6323 strict_overflow_p)) != 0)
6324 return fold_build2 (tcode, ctype, fold_convert (ctype, t1),
6325 fold_convert (ctype, op1));
6326 else if (tcode == MULT_EXPR && code == MULT_EXPR
6327 && (t1 = extract_muldiv (op1, c, code, wide_type,
6328 strict_overflow_p)) != 0)
6329 return fold_build2 (tcode, ctype, fold_convert (ctype, op0),
6330 fold_convert (ctype, t1));
6331 else if (TREE_CODE (op1) != INTEGER_CST)
6334 /* If these are the same operation types, we can associate them
6335 assuming no overflow. */
6337 && 0 != (t1 = int_const_binop (MULT_EXPR, fold_convert (ctype, op1),
6338 fold_convert (ctype, c), 1))
6339 && 0 != (t1 = force_fit_type_double (ctype, TREE_INT_CST_LOW (t1),
6340 TREE_INT_CST_HIGH (t1),
6341 (TYPE_UNSIGNED (ctype)
6342 && tcode != MULT_EXPR) ? -1 : 1,
6343 TREE_OVERFLOW (t1)))
6344 && !TREE_OVERFLOW (t1))
6345 return fold_build2 (tcode, ctype, fold_convert (ctype, op0), t1);
6347 /* If these operations "cancel" each other, we have the main
6348 optimizations of this pass, which occur when either constant is a
6349 multiple of the other, in which case we replace this with either an
6350 operation or CODE or TCODE.
6352 If we have an unsigned type that is not a sizetype, we cannot do
6353 this since it will change the result if the original computation
6355 if ((TYPE_OVERFLOW_UNDEFINED (ctype)
6356 || (TREE_CODE (ctype) == INTEGER_TYPE && TYPE_IS_SIZETYPE (ctype)))
6357 && ((code == MULT_EXPR && tcode == EXACT_DIV_EXPR)
6358 || (tcode == MULT_EXPR
6359 && code != TRUNC_MOD_EXPR && code != CEIL_MOD_EXPR
6360 && code != FLOOR_MOD_EXPR && code != ROUND_MOD_EXPR
6361 && code != MULT_EXPR)))
6363 if (integer_zerop (const_binop (TRUNC_MOD_EXPR, op1, c, 0)))
6365 if (TYPE_OVERFLOW_UNDEFINED (ctype))
6366 *strict_overflow_p = true;
6367 return fold_build2 (tcode, ctype, fold_convert (ctype, op0),
6368 fold_convert (ctype,
6369 const_binop (TRUNC_DIV_EXPR,
6372 else if (integer_zerop (const_binop (TRUNC_MOD_EXPR, c, op1, 0)))
6374 if (TYPE_OVERFLOW_UNDEFINED (ctype))
6375 *strict_overflow_p = true;
6376 return fold_build2 (code, ctype, fold_convert (ctype, op0),
6377 fold_convert (ctype,
6378 const_binop (TRUNC_DIV_EXPR,
6391 /* Return a node which has the indicated constant VALUE (either 0 or
6392 1), and is of the indicated TYPE. */
6395 constant_boolean_node (int value, tree type)
6397 if (type == integer_type_node)
6398 return value ? integer_one_node : integer_zero_node;
6399 else if (type == boolean_type_node)
6400 return value ? boolean_true_node : boolean_false_node;
6402 return build_int_cst (type, value);
6406 /* Transform `a + (b ? x : y)' into `b ? (a + x) : (a + y)'.
6407 Transform, `a + (x < y)' into `(x < y) ? (a + 1) : (a + 0)'. Here
6408 CODE corresponds to the `+', COND to the `(b ? x : y)' or `(x < y)'
6409 expression, and ARG to `a'. If COND_FIRST_P is nonzero, then the
6410 COND is the first argument to CODE; otherwise (as in the example
6411 given here), it is the second argument. TYPE is the type of the
6412 original expression. Return NULL_TREE if no simplification is
6416 fold_binary_op_with_conditional_arg (enum tree_code code,
6417 tree type, tree op0, tree op1,
6418 tree cond, tree arg, int cond_first_p)
6420 tree cond_type = cond_first_p ? TREE_TYPE (op0) : TREE_TYPE (op1);
6421 tree arg_type = cond_first_p ? TREE_TYPE (op1) : TREE_TYPE (op0);
6422 tree test, true_value, false_value;
6423 tree lhs = NULL_TREE;
6424 tree rhs = NULL_TREE;
6426 /* This transformation is only worthwhile if we don't have to wrap
6427 arg in a SAVE_EXPR, and the operation can be simplified on at least
6428 one of the branches once its pushed inside the COND_EXPR. */
6429 if (!TREE_CONSTANT (arg))
6432 if (TREE_CODE (cond) == COND_EXPR)
6434 test = TREE_OPERAND (cond, 0);
6435 true_value = TREE_OPERAND (cond, 1);
6436 false_value = TREE_OPERAND (cond, 2);
6437 /* If this operand throws an expression, then it does not make
6438 sense to try to perform a logical or arithmetic operation
6440 if (VOID_TYPE_P (TREE_TYPE (true_value)))
6442 if (VOID_TYPE_P (TREE_TYPE (false_value)))
6447 tree testtype = TREE_TYPE (cond);
6449 true_value = constant_boolean_node (true, testtype);
6450 false_value = constant_boolean_node (false, testtype);
6453 arg = fold_convert (arg_type, arg);
6456 true_value = fold_convert (cond_type, true_value);
6458 lhs = fold_build2 (code, type, true_value, arg);
6460 lhs = fold_build2 (code, type, arg, true_value);
6464 false_value = fold_convert (cond_type, false_value);
6466 rhs = fold_build2 (code, type, false_value, arg);
6468 rhs = fold_build2 (code, type, arg, false_value);
6471 test = fold_build3 (COND_EXPR, type, test, lhs, rhs);
6472 return fold_convert (type, test);
6476 /* Subroutine of fold() that checks for the addition of +/- 0.0.
6478 If !NEGATE, return true if ADDEND is +/-0.0 and, for all X of type
6479 TYPE, X + ADDEND is the same as X. If NEGATE, return true if X -
6480 ADDEND is the same as X.
6482 X + 0 and X - 0 both give X when X is NaN, infinite, or nonzero
6483 and finite. The problematic cases are when X is zero, and its mode
6484 has signed zeros. In the case of rounding towards -infinity,
6485 X - 0 is not the same as X because 0 - 0 is -0. In other rounding
6486 modes, X + 0 is not the same as X because -0 + 0 is 0. */
6489 fold_real_zero_addition_p (const_tree type, const_tree addend, int negate)
6491 if (!real_zerop (addend))
6494 /* Don't allow the fold with -fsignaling-nans. */
6495 if (HONOR_SNANS (TYPE_MODE (type)))
6498 /* Allow the fold if zeros aren't signed, or their sign isn't important. */
6499 if (!HONOR_SIGNED_ZEROS (TYPE_MODE (type)))
6502 /* Treat x + -0 as x - 0 and x - -0 as x + 0. */
6503 if (TREE_CODE (addend) == REAL_CST
6504 && REAL_VALUE_MINUS_ZERO (TREE_REAL_CST (addend)))
6507 /* The mode has signed zeros, and we have to honor their sign.
6508 In this situation, there is only one case we can return true for.
6509 X - 0 is the same as X unless rounding towards -infinity is
6511 return negate && !HONOR_SIGN_DEPENDENT_ROUNDING (TYPE_MODE (type));
6514 /* Subroutine of fold() that checks comparisons of built-in math
6515 functions against real constants.
6517 FCODE is the DECL_FUNCTION_CODE of the built-in, CODE is the comparison
6518 operator: EQ_EXPR, NE_EXPR, GT_EXPR, LT_EXPR, GE_EXPR or LE_EXPR. TYPE
6519 is the type of the result and ARG0 and ARG1 are the operands of the
6520 comparison. ARG1 must be a TREE_REAL_CST.
6522 The function returns the constant folded tree if a simplification
6523 can be made, and NULL_TREE otherwise. */
6526 fold_mathfn_compare (enum built_in_function fcode, enum tree_code code,
6527 tree type, tree arg0, tree arg1)
6531 if (BUILTIN_SQRT_P (fcode))
6533 tree arg = CALL_EXPR_ARG (arg0, 0);
6534 enum machine_mode mode = TYPE_MODE (TREE_TYPE (arg0));
6536 c = TREE_REAL_CST (arg1);
6537 if (REAL_VALUE_NEGATIVE (c))
6539 /* sqrt(x) < y is always false, if y is negative. */
6540 if (code == EQ_EXPR || code == LT_EXPR || code == LE_EXPR)
6541 return omit_one_operand (type, integer_zero_node, arg);
6543 /* sqrt(x) > y is always true, if y is negative and we
6544 don't care about NaNs, i.e. negative values of x. */
6545 if (code == NE_EXPR || !HONOR_NANS (mode))
6546 return omit_one_operand (type, integer_one_node, arg);
6548 /* sqrt(x) > y is the same as x >= 0, if y is negative. */
6549 return fold_build2 (GE_EXPR, type, arg,
6550 build_real (TREE_TYPE (arg), dconst0));
6552 else if (code == GT_EXPR || code == GE_EXPR)
6556 REAL_ARITHMETIC (c2, MULT_EXPR, c, c);
6557 real_convert (&c2, mode, &c2);
6559 if (REAL_VALUE_ISINF (c2))
6561 /* sqrt(x) > y is x == +Inf, when y is very large. */
6562 if (HONOR_INFINITIES (mode))
6563 return fold_build2 (EQ_EXPR, type, arg,
6564 build_real (TREE_TYPE (arg), c2));
6566 /* sqrt(x) > y is always false, when y is very large
6567 and we don't care about infinities. */
6568 return omit_one_operand (type, integer_zero_node, arg);
6571 /* sqrt(x) > c is the same as x > c*c. */
6572 return fold_build2 (code, type, arg,
6573 build_real (TREE_TYPE (arg), c2));
6575 else if (code == LT_EXPR || code == LE_EXPR)
6579 REAL_ARITHMETIC (c2, MULT_EXPR, c, c);
6580 real_convert (&c2, mode, &c2);
6582 if (REAL_VALUE_ISINF (c2))
6584 /* sqrt(x) < y is always true, when y is a very large
6585 value and we don't care about NaNs or Infinities. */
6586 if (! HONOR_NANS (mode) && ! HONOR_INFINITIES (mode))
6587 return omit_one_operand (type, integer_one_node, arg);
6589 /* sqrt(x) < y is x != +Inf when y is very large and we
6590 don't care about NaNs. */
6591 if (! HONOR_NANS (mode))
6592 return fold_build2 (NE_EXPR, type, arg,
6593 build_real (TREE_TYPE (arg), c2));
6595 /* sqrt(x) < y is x >= 0 when y is very large and we
6596 don't care about Infinities. */
6597 if (! HONOR_INFINITIES (mode))
6598 return fold_build2 (GE_EXPR, type, arg,
6599 build_real (TREE_TYPE (arg), dconst0));
6601 /* sqrt(x) < y is x >= 0 && x != +Inf, when y is large. */
6602 if (lang_hooks.decls.global_bindings_p () != 0
6603 || CONTAINS_PLACEHOLDER_P (arg))
6606 arg = save_expr (arg);
6607 return fold_build2 (TRUTH_ANDIF_EXPR, type,
6608 fold_build2 (GE_EXPR, type, arg,
6609 build_real (TREE_TYPE (arg),
6611 fold_build2 (NE_EXPR, type, arg,
6612 build_real (TREE_TYPE (arg),
6616 /* sqrt(x) < c is the same as x < c*c, if we ignore NaNs. */
6617 if (! HONOR_NANS (mode))
6618 return fold_build2 (code, type, arg,
6619 build_real (TREE_TYPE (arg), c2));
6621 /* sqrt(x) < c is the same as x >= 0 && x < c*c. */
6622 if (lang_hooks.decls.global_bindings_p () == 0
6623 && ! CONTAINS_PLACEHOLDER_P (arg))
6625 arg = save_expr (arg);
6626 return fold_build2 (TRUTH_ANDIF_EXPR, type,
6627 fold_build2 (GE_EXPR, type, arg,
6628 build_real (TREE_TYPE (arg),
6630 fold_build2 (code, type, arg,
6631 build_real (TREE_TYPE (arg),
6640 /* Subroutine of fold() that optimizes comparisons against Infinities,
6641 either +Inf or -Inf.
6643 CODE is the comparison operator: EQ_EXPR, NE_EXPR, GT_EXPR, LT_EXPR,
6644 GE_EXPR or LE_EXPR. TYPE is the type of the result and ARG0 and ARG1
6645 are the operands of the comparison. ARG1 must be a TREE_REAL_CST.
6647 The function returns the constant folded tree if a simplification
6648 can be made, and NULL_TREE otherwise. */
6651 fold_inf_compare (enum tree_code code, tree type, tree arg0, tree arg1)
6653 enum machine_mode mode;
6654 REAL_VALUE_TYPE max;
6658 mode = TYPE_MODE (TREE_TYPE (arg0));
6660 /* For negative infinity swap the sense of the comparison. */
6661 neg = REAL_VALUE_NEGATIVE (TREE_REAL_CST (arg1));
6663 code = swap_tree_comparison (code);
6668 /* x > +Inf is always false, if with ignore sNANs. */
6669 if (HONOR_SNANS (mode))
6671 return omit_one_operand (type, integer_zero_node, arg0);
6674 /* x <= +Inf is always true, if we don't case about NaNs. */
6675 if (! HONOR_NANS (mode))
6676 return omit_one_operand (type, integer_one_node, arg0);
6678 /* x <= +Inf is the same as x == x, i.e. isfinite(x). */
6679 if (lang_hooks.decls.global_bindings_p () == 0
6680 && ! CONTAINS_PLACEHOLDER_P (arg0))
6682 arg0 = save_expr (arg0);
6683 return fold_build2 (EQ_EXPR, type, arg0, arg0);
6689 /* x == +Inf and x >= +Inf are always equal to x > DBL_MAX. */
6690 real_maxval (&max, neg, mode);
6691 return fold_build2 (neg ? LT_EXPR : GT_EXPR, type,
6692 arg0, build_real (TREE_TYPE (arg0), max));
6695 /* x < +Inf is always equal to x <= DBL_MAX. */
6696 real_maxval (&max, neg, mode);
6697 return fold_build2 (neg ? GE_EXPR : LE_EXPR, type,
6698 arg0, build_real (TREE_TYPE (arg0), max));
6701 /* x != +Inf is always equal to !(x > DBL_MAX). */
6702 real_maxval (&max, neg, mode);
6703 if (! HONOR_NANS (mode))
6704 return fold_build2 (neg ? GE_EXPR : LE_EXPR, type,
6705 arg0, build_real (TREE_TYPE (arg0), max));
6707 temp = fold_build2 (neg ? LT_EXPR : GT_EXPR, type,
6708 arg0, build_real (TREE_TYPE (arg0), max));
6709 return fold_build1 (TRUTH_NOT_EXPR, type, temp);
6718 /* Subroutine of fold() that optimizes comparisons of a division by
6719 a nonzero integer constant against an integer constant, i.e.
6722 CODE is the comparison operator: EQ_EXPR, NE_EXPR, GT_EXPR, LT_EXPR,
6723 GE_EXPR or LE_EXPR. TYPE is the type of the result and ARG0 and ARG1
6724 are the operands of the comparison. ARG1 must be a TREE_REAL_CST.
6726 The function returns the constant folded tree if a simplification
6727 can be made, and NULL_TREE otherwise. */
6730 fold_div_compare (enum tree_code code, tree type, tree arg0, tree arg1)
6732 tree prod, tmp, hi, lo;
6733 tree arg00 = TREE_OPERAND (arg0, 0);
6734 tree arg01 = TREE_OPERAND (arg0, 1);
6735 unsigned HOST_WIDE_INT lpart;
6736 HOST_WIDE_INT hpart;
6737 bool unsigned_p = TYPE_UNSIGNED (TREE_TYPE (arg0));
6741 /* We have to do this the hard way to detect unsigned overflow.
6742 prod = int_const_binop (MULT_EXPR, arg01, arg1, 0); */
6743 overflow = mul_double_with_sign (TREE_INT_CST_LOW (arg01),
6744 TREE_INT_CST_HIGH (arg01),
6745 TREE_INT_CST_LOW (arg1),
6746 TREE_INT_CST_HIGH (arg1),
6747 &lpart, &hpart, unsigned_p);
6748 prod = force_fit_type_double (TREE_TYPE (arg00), lpart, hpart,
6750 neg_overflow = false;
6754 tmp = int_const_binop (MINUS_EXPR, arg01,
6755 build_int_cst (TREE_TYPE (arg01), 1), 0);
6758 /* Likewise hi = int_const_binop (PLUS_EXPR, prod, tmp, 0). */
6759 overflow = add_double_with_sign (TREE_INT_CST_LOW (prod),
6760 TREE_INT_CST_HIGH (prod),
6761 TREE_INT_CST_LOW (tmp),
6762 TREE_INT_CST_HIGH (tmp),
6763 &lpart, &hpart, unsigned_p);
6764 hi = force_fit_type_double (TREE_TYPE (arg00), lpart, hpart,
6765 -1, overflow | TREE_OVERFLOW (prod));
6767 else if (tree_int_cst_sgn (arg01) >= 0)
6769 tmp = int_const_binop (MINUS_EXPR, arg01,
6770 build_int_cst (TREE_TYPE (arg01), 1), 0);
6771 switch (tree_int_cst_sgn (arg1))
6774 neg_overflow = true;
6775 lo = int_const_binop (MINUS_EXPR, prod, tmp, 0);
6780 lo = fold_negate_const (tmp, TREE_TYPE (arg0));
6785 hi = int_const_binop (PLUS_EXPR, prod, tmp, 0);
6795 /* A negative divisor reverses the relational operators. */
6796 code = swap_tree_comparison (code);
6798 tmp = int_const_binop (PLUS_EXPR, arg01,
6799 build_int_cst (TREE_TYPE (arg01), 1), 0);
6800 switch (tree_int_cst_sgn (arg1))
6803 hi = int_const_binop (MINUS_EXPR, prod, tmp, 0);
6808 hi = fold_negate_const (tmp, TREE_TYPE (arg0));
6813 neg_overflow = true;
6814 lo = int_const_binop (PLUS_EXPR, prod, tmp, 0);
6826 if (TREE_OVERFLOW (lo) && TREE_OVERFLOW (hi))
6827 return omit_one_operand (type, integer_zero_node, arg00);
6828 if (TREE_OVERFLOW (hi))
6829 return fold_build2 (GE_EXPR, type, arg00, lo);
6830 if (TREE_OVERFLOW (lo))
6831 return fold_build2 (LE_EXPR, type, arg00, hi);
6832 return build_range_check (type, arg00, 1, lo, hi);
6835 if (TREE_OVERFLOW (lo) && TREE_OVERFLOW (hi))
6836 return omit_one_operand (type, integer_one_node, arg00);
6837 if (TREE_OVERFLOW (hi))
6838 return fold_build2 (LT_EXPR, type, arg00, lo);
6839 if (TREE_OVERFLOW (lo))
6840 return fold_build2 (GT_EXPR, type, arg00, hi);
6841 return build_range_check (type, arg00, 0, lo, hi);
6844 if (TREE_OVERFLOW (lo))
6846 tmp = neg_overflow ? integer_zero_node : integer_one_node;
6847 return omit_one_operand (type, tmp, arg00);
6849 return fold_build2 (LT_EXPR, type, arg00, lo);
6852 if (TREE_OVERFLOW (hi))
6854 tmp = neg_overflow ? integer_zero_node : integer_one_node;
6855 return omit_one_operand (type, tmp, arg00);
6857 return fold_build2 (LE_EXPR, type, arg00, hi);
6860 if (TREE_OVERFLOW (hi))
6862 tmp = neg_overflow ? integer_one_node : integer_zero_node;
6863 return omit_one_operand (type, tmp, arg00);
6865 return fold_build2 (GT_EXPR, type, arg00, hi);
6868 if (TREE_OVERFLOW (lo))
6870 tmp = neg_overflow ? integer_one_node : integer_zero_node;
6871 return omit_one_operand (type, tmp, arg00);
6873 return fold_build2 (GE_EXPR, type, arg00, lo);
6883 /* If CODE with arguments ARG0 and ARG1 represents a single bit
6884 equality/inequality test, then return a simplified form of the test
6885 using a sign testing. Otherwise return NULL. TYPE is the desired
6889 fold_single_bit_test_into_sign_test (enum tree_code code, tree arg0, tree arg1,
6892 /* If this is testing a single bit, we can optimize the test. */
6893 if ((code == NE_EXPR || code == EQ_EXPR)
6894 && TREE_CODE (arg0) == BIT_AND_EXPR && integer_zerop (arg1)
6895 && integer_pow2p (TREE_OPERAND (arg0, 1)))
6897 /* If we have (A & C) != 0 where C is the sign bit of A, convert
6898 this into A < 0. Similarly for (A & C) == 0 into A >= 0. */
6899 tree arg00 = sign_bit_p (TREE_OPERAND (arg0, 0), TREE_OPERAND (arg0, 1));
6901 if (arg00 != NULL_TREE
6902 /* This is only a win if casting to a signed type is cheap,
6903 i.e. when arg00's type is not a partial mode. */
6904 && TYPE_PRECISION (TREE_TYPE (arg00))
6905 == GET_MODE_BITSIZE (TYPE_MODE (TREE_TYPE (arg00))))
6907 tree stype = signed_type_for (TREE_TYPE (arg00));
6908 return fold_build2 (code == EQ_EXPR ? GE_EXPR : LT_EXPR,
6909 result_type, fold_convert (stype, arg00),
6910 build_int_cst (stype, 0));
6917 /* If CODE with arguments ARG0 and ARG1 represents a single bit
6918 equality/inequality test, then return a simplified form of
6919 the test using shifts and logical operations. Otherwise return
6920 NULL. TYPE is the desired result type. */
6923 fold_single_bit_test (enum tree_code code, tree arg0, tree arg1,
6926 /* If this is testing a single bit, we can optimize the test. */
6927 if ((code == NE_EXPR || code == EQ_EXPR)
6928 && TREE_CODE (arg0) == BIT_AND_EXPR && integer_zerop (arg1)
6929 && integer_pow2p (TREE_OPERAND (arg0, 1)))
6931 tree inner = TREE_OPERAND (arg0, 0);
6932 tree type = TREE_TYPE (arg0);
6933 int bitnum = tree_log2 (TREE_OPERAND (arg0, 1));
6934 enum machine_mode operand_mode = TYPE_MODE (type);
6936 tree signed_type, unsigned_type, intermediate_type;
6939 /* First, see if we can fold the single bit test into a sign-bit
6941 tem = fold_single_bit_test_into_sign_test (code, arg0, arg1,
6946 /* Otherwise we have (A & C) != 0 where C is a single bit,
6947 convert that into ((A >> C2) & 1). Where C2 = log2(C).
6948 Similarly for (A & C) == 0. */
6950 /* If INNER is a right shift of a constant and it plus BITNUM does
6951 not overflow, adjust BITNUM and INNER. */
6952 if (TREE_CODE (inner) == RSHIFT_EXPR
6953 && TREE_CODE (TREE_OPERAND (inner, 1)) == INTEGER_CST
6954 && TREE_INT_CST_HIGH (TREE_OPERAND (inner, 1)) == 0
6955 && bitnum < TYPE_PRECISION (type)
6956 && 0 > compare_tree_int (TREE_OPERAND (inner, 1),
6957 bitnum - TYPE_PRECISION (type)))
6959 bitnum += TREE_INT_CST_LOW (TREE_OPERAND (inner, 1));
6960 inner = TREE_OPERAND (inner, 0);
6963 /* If we are going to be able to omit the AND below, we must do our
6964 operations as unsigned. If we must use the AND, we have a choice.
6965 Normally unsigned is faster, but for some machines signed is. */
6966 #ifdef LOAD_EXTEND_OP
6967 ops_unsigned = (LOAD_EXTEND_OP (operand_mode) == SIGN_EXTEND
6968 && !flag_syntax_only) ? 0 : 1;
6973 signed_type = lang_hooks.types.type_for_mode (operand_mode, 0);
6974 unsigned_type = lang_hooks.types.type_for_mode (operand_mode, 1);
6975 intermediate_type = ops_unsigned ? unsigned_type : signed_type;
6976 inner = fold_convert (intermediate_type, inner);
6979 inner = build2 (RSHIFT_EXPR, intermediate_type,
6980 inner, size_int (bitnum));
6982 one = build_int_cst (intermediate_type, 1);
6984 if (code == EQ_EXPR)
6985 inner = fold_build2 (BIT_XOR_EXPR, intermediate_type, inner, one);
6987 /* Put the AND last so it can combine with more things. */
6988 inner = build2 (BIT_AND_EXPR, intermediate_type, inner, one);
6990 /* Make sure to return the proper type. */
6991 inner = fold_convert (result_type, inner);
6998 /* Check whether we are allowed to reorder operands arg0 and arg1,
6999 such that the evaluation of arg1 occurs before arg0. */
7002 reorder_operands_p (const_tree arg0, const_tree arg1)
7004 if (! flag_evaluation_order)
7006 if (TREE_CONSTANT (arg0) || TREE_CONSTANT (arg1))
7008 return ! TREE_SIDE_EFFECTS (arg0)
7009 && ! TREE_SIDE_EFFECTS (arg1);
7012 /* Test whether it is preferable two swap two operands, ARG0 and
7013 ARG1, for example because ARG0 is an integer constant and ARG1
7014 isn't. If REORDER is true, only recommend swapping if we can
7015 evaluate the operands in reverse order. */
7018 tree_swap_operands_p (const_tree arg0, const_tree arg1, bool reorder)
7020 STRIP_SIGN_NOPS (arg0);
7021 STRIP_SIGN_NOPS (arg1);
7023 if (TREE_CODE (arg1) == INTEGER_CST)
7025 if (TREE_CODE (arg0) == INTEGER_CST)
7028 if (TREE_CODE (arg1) == REAL_CST)
7030 if (TREE_CODE (arg0) == REAL_CST)
7033 if (TREE_CODE (arg1) == FIXED_CST)
7035 if (TREE_CODE (arg0) == FIXED_CST)
7038 if (TREE_CODE (arg1) == COMPLEX_CST)
7040 if (TREE_CODE (arg0) == COMPLEX_CST)
7043 if (TREE_CONSTANT (arg1))
7045 if (TREE_CONSTANT (arg0))
7048 if (optimize_function_for_size_p (cfun))
7051 if (reorder && flag_evaluation_order
7052 && (TREE_SIDE_EFFECTS (arg0) || TREE_SIDE_EFFECTS (arg1)))
7055 /* It is preferable to swap two SSA_NAME to ensure a canonical form
7056 for commutative and comparison operators. Ensuring a canonical
7057 form allows the optimizers to find additional redundancies without
7058 having to explicitly check for both orderings. */
7059 if (TREE_CODE (arg0) == SSA_NAME
7060 && TREE_CODE (arg1) == SSA_NAME
7061 && SSA_NAME_VERSION (arg0) > SSA_NAME_VERSION (arg1))
7064 /* Put SSA_NAMEs last. */
7065 if (TREE_CODE (arg1) == SSA_NAME)
7067 if (TREE_CODE (arg0) == SSA_NAME)
7070 /* Put variables last. */
7079 /* Fold comparison ARG0 CODE ARG1 (with result in TYPE), where
7080 ARG0 is extended to a wider type. */
7083 fold_widened_comparison (enum tree_code code, tree type, tree arg0, tree arg1)
7085 tree arg0_unw = get_unwidened (arg0, NULL_TREE);
7087 tree shorter_type, outer_type;
7091 if (arg0_unw == arg0)
7093 shorter_type = TREE_TYPE (arg0_unw);
7095 #ifdef HAVE_canonicalize_funcptr_for_compare
7096 /* Disable this optimization if we're casting a function pointer
7097 type on targets that require function pointer canonicalization. */
7098 if (HAVE_canonicalize_funcptr_for_compare
7099 && TREE_CODE (shorter_type) == POINTER_TYPE
7100 && TREE_CODE (TREE_TYPE (shorter_type)) == FUNCTION_TYPE)
7104 if (TYPE_PRECISION (TREE_TYPE (arg0)) <= TYPE_PRECISION (shorter_type))
7107 arg1_unw = get_unwidened (arg1, NULL_TREE);
7109 /* If possible, express the comparison in the shorter mode. */
7110 if ((code == EQ_EXPR || code == NE_EXPR
7111 || TYPE_UNSIGNED (TREE_TYPE (arg0)) == TYPE_UNSIGNED (shorter_type))
7112 && (TREE_TYPE (arg1_unw) == shorter_type
7113 || ((TYPE_PRECISION (shorter_type)
7114 >= TYPE_PRECISION (TREE_TYPE (arg1_unw)))
7115 && (TYPE_UNSIGNED (shorter_type)
7116 == TYPE_UNSIGNED (TREE_TYPE (arg1_unw))))
7117 || (TREE_CODE (arg1_unw) == INTEGER_CST
7118 && (TREE_CODE (shorter_type) == INTEGER_TYPE
7119 || TREE_CODE (shorter_type) == BOOLEAN_TYPE)
7120 && int_fits_type_p (arg1_unw, shorter_type))))
7121 return fold_build2 (code, type, arg0_unw,
7122 fold_convert (shorter_type, arg1_unw));
7124 if (TREE_CODE (arg1_unw) != INTEGER_CST
7125 || TREE_CODE (shorter_type) != INTEGER_TYPE
7126 || !int_fits_type_p (arg1_unw, shorter_type))
7129 /* If we are comparing with the integer that does not fit into the range
7130 of the shorter type, the result is known. */
7131 outer_type = TREE_TYPE (arg1_unw);
7132 min = lower_bound_in_type (outer_type, shorter_type);
7133 max = upper_bound_in_type (outer_type, shorter_type);
7135 above = integer_nonzerop (fold_relational_const (LT_EXPR, type,
7137 below = integer_nonzerop (fold_relational_const (LT_EXPR, type,
7144 return omit_one_operand (type, integer_zero_node, arg0);
7149 return omit_one_operand (type, integer_one_node, arg0);
7155 return omit_one_operand (type, integer_one_node, arg0);
7157 return omit_one_operand (type, integer_zero_node, arg0);
7162 return omit_one_operand (type, integer_zero_node, arg0);
7164 return omit_one_operand (type, integer_one_node, arg0);
7173 /* Fold comparison ARG0 CODE ARG1 (with result in TYPE), where for
7174 ARG0 just the signedness is changed. */
7177 fold_sign_changed_comparison (enum tree_code code, tree type,
7178 tree arg0, tree arg1)
7181 tree inner_type, outer_type;
7183 if (!CONVERT_EXPR_P (arg0))
7186 outer_type = TREE_TYPE (arg0);
7187 arg0_inner = TREE_OPERAND (arg0, 0);
7188 inner_type = TREE_TYPE (arg0_inner);
7190 #ifdef HAVE_canonicalize_funcptr_for_compare
7191 /* Disable this optimization if we're casting a function pointer
7192 type on targets that require function pointer canonicalization. */
7193 if (HAVE_canonicalize_funcptr_for_compare
7194 && TREE_CODE (inner_type) == POINTER_TYPE
7195 && TREE_CODE (TREE_TYPE (inner_type)) == FUNCTION_TYPE)
7199 if (TYPE_PRECISION (inner_type) != TYPE_PRECISION (outer_type))
7202 /* If the conversion is from an integral subtype to its basetype
7204 if (TREE_TYPE (inner_type) == outer_type)
7207 if (TREE_CODE (arg1) != INTEGER_CST
7208 && !(CONVERT_EXPR_P (arg1)
7209 && TREE_TYPE (TREE_OPERAND (arg1, 0)) == inner_type))
7212 if ((TYPE_UNSIGNED (inner_type) != TYPE_UNSIGNED (outer_type)
7213 || POINTER_TYPE_P (inner_type) != POINTER_TYPE_P (outer_type))
7218 if (TREE_CODE (arg1) == INTEGER_CST)
7219 arg1 = force_fit_type_double (inner_type, TREE_INT_CST_LOW (arg1),
7220 TREE_INT_CST_HIGH (arg1), 0,
7221 TREE_OVERFLOW (arg1));
7223 arg1 = fold_convert (inner_type, arg1);
7225 return fold_build2 (code, type, arg0_inner, arg1);
7228 /* Tries to replace &a[idx] p+ s * delta with &a[idx + delta], if s is
7229 step of the array. Reconstructs s and delta in the case of s * delta
7230 being an integer constant (and thus already folded).
7231 ADDR is the address. MULT is the multiplicative expression.
7232 If the function succeeds, the new address expression is returned. Otherwise
7233 NULL_TREE is returned. */
7236 try_move_mult_to_index (tree addr, tree op1)
7238 tree s, delta, step;
7239 tree ref = TREE_OPERAND (addr, 0), pref;
7244 /* Strip the nops that might be added when converting op1 to sizetype. */
7247 /* Canonicalize op1 into a possibly non-constant delta
7248 and an INTEGER_CST s. */
7249 if (TREE_CODE (op1) == MULT_EXPR)
7251 tree arg0 = TREE_OPERAND (op1, 0), arg1 = TREE_OPERAND (op1, 1);
7256 if (TREE_CODE (arg0) == INTEGER_CST)
7261 else if (TREE_CODE (arg1) == INTEGER_CST)
7269 else if (TREE_CODE (op1) == INTEGER_CST)
7276 /* Simulate we are delta * 1. */
7278 s = integer_one_node;
7281 for (;; ref = TREE_OPERAND (ref, 0))
7283 if (TREE_CODE (ref) == ARRAY_REF)
7285 /* Remember if this was a multi-dimensional array. */
7286 if (TREE_CODE (TREE_OPERAND (ref, 0)) == ARRAY_REF)
7289 itype = TYPE_DOMAIN (TREE_TYPE (TREE_OPERAND (ref, 0)));
7293 step = array_ref_element_size (ref);
7294 if (TREE_CODE (step) != INTEGER_CST)
7299 if (! tree_int_cst_equal (step, s))
7304 /* Try if delta is a multiple of step. */
7305 tree tmp = div_if_zero_remainder (EXACT_DIV_EXPR, op1, step);
7311 /* Only fold here if we can verify we do not overflow one
7312 dimension of a multi-dimensional array. */
7317 if (TREE_CODE (TREE_OPERAND (ref, 1)) != INTEGER_CST
7318 || !INTEGRAL_TYPE_P (itype)
7319 || !TYPE_MAX_VALUE (itype)
7320 || TREE_CODE (TYPE_MAX_VALUE (itype)) != INTEGER_CST)
7323 tmp = fold_binary (PLUS_EXPR, itype,
7324 fold_convert (itype,
7325 TREE_OPERAND (ref, 1)),
7326 fold_convert (itype, delta));
7328 || TREE_CODE (tmp) != INTEGER_CST
7329 || tree_int_cst_lt (TYPE_MAX_VALUE (itype), tmp))
7338 if (!handled_component_p (ref))
7342 /* We found the suitable array reference. So copy everything up to it,
7343 and replace the index. */
7345 pref = TREE_OPERAND (addr, 0);
7346 ret = copy_node (pref);
7351 pref = TREE_OPERAND (pref, 0);
7352 TREE_OPERAND (pos, 0) = copy_node (pref);
7353 pos = TREE_OPERAND (pos, 0);
7356 TREE_OPERAND (pos, 1) = fold_build2 (PLUS_EXPR, itype,
7357 fold_convert (itype,
7358 TREE_OPERAND (pos, 1)),
7359 fold_convert (itype, delta));
7361 return fold_build1 (ADDR_EXPR, TREE_TYPE (addr), ret);
7365 /* Fold A < X && A + 1 > Y to A < X && A >= Y. Normally A + 1 > Y
7366 means A >= Y && A != MAX, but in this case we know that
7367 A < X <= MAX. INEQ is A + 1 > Y, BOUND is A < X. */
7370 fold_to_nonsharp_ineq_using_bound (tree ineq, tree bound)
7372 tree a, typea, type = TREE_TYPE (ineq), a1, diff, y;
7374 if (TREE_CODE (bound) == LT_EXPR)
7375 a = TREE_OPERAND (bound, 0);
7376 else if (TREE_CODE (bound) == GT_EXPR)
7377 a = TREE_OPERAND (bound, 1);
7381 typea = TREE_TYPE (a);
7382 if (!INTEGRAL_TYPE_P (typea)
7383 && !POINTER_TYPE_P (typea))
7386 if (TREE_CODE (ineq) == LT_EXPR)
7388 a1 = TREE_OPERAND (ineq, 1);
7389 y = TREE_OPERAND (ineq, 0);
7391 else if (TREE_CODE (ineq) == GT_EXPR)
7393 a1 = TREE_OPERAND (ineq, 0);
7394 y = TREE_OPERAND (ineq, 1);
7399 if (TREE_TYPE (a1) != typea)
7402 if (POINTER_TYPE_P (typea))
7404 /* Convert the pointer types into integer before taking the difference. */
7405 tree ta = fold_convert (ssizetype, a);
7406 tree ta1 = fold_convert (ssizetype, a1);
7407 diff = fold_binary (MINUS_EXPR, ssizetype, ta1, ta);
7410 diff = fold_binary (MINUS_EXPR, typea, a1, a);
7412 if (!diff || !integer_onep (diff))
7415 return fold_build2 (GE_EXPR, type, a, y);
7418 /* Fold a sum or difference of at least one multiplication.
7419 Returns the folded tree or NULL if no simplification could be made. */
7422 fold_plusminus_mult_expr (enum tree_code code, tree type, tree arg0, tree arg1)
7424 tree arg00, arg01, arg10, arg11;
7425 tree alt0 = NULL_TREE, alt1 = NULL_TREE, same;
7427 /* (A * C) +- (B * C) -> (A+-B) * C.
7428 (A * C) +- A -> A * (C+-1).
7429 We are most concerned about the case where C is a constant,
7430 but other combinations show up during loop reduction. Since
7431 it is not difficult, try all four possibilities. */
7433 if (TREE_CODE (arg0) == MULT_EXPR)
7435 arg00 = TREE_OPERAND (arg0, 0);
7436 arg01 = TREE_OPERAND (arg0, 1);
7438 else if (TREE_CODE (arg0) == INTEGER_CST)
7440 arg00 = build_one_cst (type);
7445 /* We cannot generate constant 1 for fract. */
7446 if (ALL_FRACT_MODE_P (TYPE_MODE (type)))
7449 arg01 = build_one_cst (type);
7451 if (TREE_CODE (arg1) == MULT_EXPR)
7453 arg10 = TREE_OPERAND (arg1, 0);
7454 arg11 = TREE_OPERAND (arg1, 1);
7456 else if (TREE_CODE (arg1) == INTEGER_CST)
7458 arg10 = build_one_cst (type);
7459 /* As we canonicalize A - 2 to A + -2 get rid of that sign for
7460 the purpose of this canonicalization. */
7461 if (TREE_INT_CST_HIGH (arg1) == -1
7462 && negate_expr_p (arg1)
7463 && code == PLUS_EXPR)
7465 arg11 = negate_expr (arg1);
7473 /* We cannot generate constant 1 for fract. */
7474 if (ALL_FRACT_MODE_P (TYPE_MODE (type)))
7477 arg11 = build_one_cst (type);
7481 if (operand_equal_p (arg01, arg11, 0))
7482 same = arg01, alt0 = arg00, alt1 = arg10;
7483 else if (operand_equal_p (arg00, arg10, 0))
7484 same = arg00, alt0 = arg01, alt1 = arg11;
7485 else if (operand_equal_p (arg00, arg11, 0))
7486 same = arg00, alt0 = arg01, alt1 = arg10;
7487 else if (operand_equal_p (arg01, arg10, 0))
7488 same = arg01, alt0 = arg00, alt1 = arg11;
7490 /* No identical multiplicands; see if we can find a common
7491 power-of-two factor in non-power-of-two multiplies. This
7492 can help in multi-dimensional array access. */
7493 else if (host_integerp (arg01, 0)
7494 && host_integerp (arg11, 0))
7496 HOST_WIDE_INT int01, int11, tmp;
7499 int01 = TREE_INT_CST_LOW (arg01);
7500 int11 = TREE_INT_CST_LOW (arg11);
7502 /* Move min of absolute values to int11. */
7503 if ((int01 >= 0 ? int01 : -int01)
7504 < (int11 >= 0 ? int11 : -int11))
7506 tmp = int01, int01 = int11, int11 = tmp;
7507 alt0 = arg00, arg00 = arg10, arg10 = alt0;
7514 if (exact_log2 (abs (int11)) > 0 && int01 % int11 == 0
7515 /* The remainder should not be a constant, otherwise we
7516 end up folding i * 4 + 2 to (i * 2 + 1) * 2 which has
7517 increased the number of multiplications necessary. */
7518 && TREE_CODE (arg10) != INTEGER_CST)
7520 alt0 = fold_build2 (MULT_EXPR, TREE_TYPE (arg00), arg00,
7521 build_int_cst (TREE_TYPE (arg00),
7526 maybe_same = alt0, alt0 = alt1, alt1 = maybe_same;
7531 return fold_build2 (MULT_EXPR, type,
7532 fold_build2 (code, type,
7533 fold_convert (type, alt0),
7534 fold_convert (type, alt1)),
7535 fold_convert (type, same));
7540 /* Subroutine of native_encode_expr. Encode the INTEGER_CST
7541 specified by EXPR into the buffer PTR of length LEN bytes.
7542 Return the number of bytes placed in the buffer, or zero
7546 native_encode_int (const_tree expr, unsigned char *ptr, int len)
7548 tree type = TREE_TYPE (expr);
7549 int total_bytes = GET_MODE_SIZE (TYPE_MODE (type));
7550 int byte, offset, word, words;
7551 unsigned char value;
7553 if (total_bytes > len)
7555 words = total_bytes / UNITS_PER_WORD;
7557 for (byte = 0; byte < total_bytes; byte++)
7559 int bitpos = byte * BITS_PER_UNIT;
7560 if (bitpos < HOST_BITS_PER_WIDE_INT)
7561 value = (unsigned char) (TREE_INT_CST_LOW (expr) >> bitpos);
7563 value = (unsigned char) (TREE_INT_CST_HIGH (expr)
7564 >> (bitpos - HOST_BITS_PER_WIDE_INT));
7566 if (total_bytes > UNITS_PER_WORD)
7568 word = byte / UNITS_PER_WORD;
7569 if (WORDS_BIG_ENDIAN)
7570 word = (words - 1) - word;
7571 offset = word * UNITS_PER_WORD;
7572 if (BYTES_BIG_ENDIAN)
7573 offset += (UNITS_PER_WORD - 1) - (byte % UNITS_PER_WORD);
7575 offset += byte % UNITS_PER_WORD;
7578 offset = BYTES_BIG_ENDIAN ? (total_bytes - 1) - byte : byte;
7579 ptr[offset] = value;
7585 /* Subroutine of native_encode_expr. Encode the REAL_CST
7586 specified by EXPR into the buffer PTR of length LEN bytes.
7587 Return the number of bytes placed in the buffer, or zero
7591 native_encode_real (const_tree expr, unsigned char *ptr, int len)
7593 tree type = TREE_TYPE (expr);
7594 int total_bytes = GET_MODE_SIZE (TYPE_MODE (type));
7595 int byte, offset, word, words, bitpos;
7596 unsigned char value;
7598 /* There are always 32 bits in each long, no matter the size of
7599 the hosts long. We handle floating point representations with
7603 if (total_bytes > len)
7605 words = (32 / BITS_PER_UNIT) / UNITS_PER_WORD;
7607 real_to_target (tmp, TREE_REAL_CST_PTR (expr), TYPE_MODE (type));
7609 for (bitpos = 0; bitpos < total_bytes * BITS_PER_UNIT;
7610 bitpos += BITS_PER_UNIT)
7612 byte = (bitpos / BITS_PER_UNIT) & 3;
7613 value = (unsigned char) (tmp[bitpos / 32] >> (bitpos & 31));
7615 if (UNITS_PER_WORD < 4)
7617 word = byte / UNITS_PER_WORD;
7618 if (WORDS_BIG_ENDIAN)
7619 word = (words - 1) - word;
7620 offset = word * UNITS_PER_WORD;
7621 if (BYTES_BIG_ENDIAN)
7622 offset += (UNITS_PER_WORD - 1) - (byte % UNITS_PER_WORD);
7624 offset += byte % UNITS_PER_WORD;
7627 offset = BYTES_BIG_ENDIAN ? 3 - byte : byte;
7628 ptr[offset + ((bitpos / BITS_PER_UNIT) & ~3)] = value;
7633 /* Subroutine of native_encode_expr. Encode the COMPLEX_CST
7634 specified by EXPR into the buffer PTR of length LEN bytes.
7635 Return the number of bytes placed in the buffer, or zero
7639 native_encode_complex (const_tree expr, unsigned char *ptr, int len)
7644 part = TREE_REALPART (expr);
7645 rsize = native_encode_expr (part, ptr, len);
7648 part = TREE_IMAGPART (expr);
7649 isize = native_encode_expr (part, ptr+rsize, len-rsize);
7652 return rsize + isize;
7656 /* Subroutine of native_encode_expr. Encode the VECTOR_CST
7657 specified by EXPR into the buffer PTR of length LEN bytes.
7658 Return the number of bytes placed in the buffer, or zero
7662 native_encode_vector (const_tree expr, unsigned char *ptr, int len)
7664 int i, size, offset, count;
7665 tree itype, elem, elements;
7668 elements = TREE_VECTOR_CST_ELTS (expr);
7669 count = TYPE_VECTOR_SUBPARTS (TREE_TYPE (expr));
7670 itype = TREE_TYPE (TREE_TYPE (expr));
7671 size = GET_MODE_SIZE (TYPE_MODE (itype));
7672 for (i = 0; i < count; i++)
7676 elem = TREE_VALUE (elements);
7677 elements = TREE_CHAIN (elements);
7684 if (native_encode_expr (elem, ptr+offset, len-offset) != size)
7689 if (offset + size > len)
7691 memset (ptr+offset, 0, size);
7699 /* Subroutine of native_encode_expr. Encode the STRING_CST
7700 specified by EXPR into the buffer PTR of length LEN bytes.
7701 Return the number of bytes placed in the buffer, or zero
7705 native_encode_string (const_tree expr, unsigned char *ptr, int len)
7707 tree type = TREE_TYPE (expr);
7708 HOST_WIDE_INT total_bytes;
7710 if (TREE_CODE (type) != ARRAY_TYPE
7711 || TREE_CODE (TREE_TYPE (type)) != INTEGER_TYPE
7712 || GET_MODE_BITSIZE (TYPE_MODE (TREE_TYPE (type))) != BITS_PER_UNIT
7713 || !host_integerp (TYPE_SIZE_UNIT (type), 0))
7715 total_bytes = tree_low_cst (TYPE_SIZE_UNIT (type), 0);
7716 if (total_bytes > len)
7718 if (TREE_STRING_LENGTH (expr) < total_bytes)
7720 memcpy (ptr, TREE_STRING_POINTER (expr), TREE_STRING_LENGTH (expr));
7721 memset (ptr + TREE_STRING_LENGTH (expr), 0,
7722 total_bytes - TREE_STRING_LENGTH (expr));
7725 memcpy (ptr, TREE_STRING_POINTER (expr), total_bytes);
7730 /* Subroutine of fold_view_convert_expr. Encode the INTEGER_CST,
7731 REAL_CST, COMPLEX_CST or VECTOR_CST specified by EXPR into the
7732 buffer PTR of length LEN bytes. Return the number of bytes
7733 placed in the buffer, or zero upon failure. */
7736 native_encode_expr (const_tree expr, unsigned char *ptr, int len)
7738 switch (TREE_CODE (expr))
7741 return native_encode_int (expr, ptr, len);
7744 return native_encode_real (expr, ptr, len);
7747 return native_encode_complex (expr, ptr, len);
7750 return native_encode_vector (expr, ptr, len);
7753 return native_encode_string (expr, ptr, len);
7761 /* Subroutine of native_interpret_expr. Interpret the contents of
7762 the buffer PTR of length LEN as an INTEGER_CST of type TYPE.
7763 If the buffer cannot be interpreted, return NULL_TREE. */
7766 native_interpret_int (tree type, const unsigned char *ptr, int len)
7768 int total_bytes = GET_MODE_SIZE (TYPE_MODE (type));
7769 int byte, offset, word, words;
7770 unsigned char value;
7771 unsigned int HOST_WIDE_INT lo = 0;
7772 HOST_WIDE_INT hi = 0;
7774 if (total_bytes > len)
7776 if (total_bytes * BITS_PER_UNIT > 2 * HOST_BITS_PER_WIDE_INT)
7778 words = total_bytes / UNITS_PER_WORD;
7780 for (byte = 0; byte < total_bytes; byte++)
7782 int bitpos = byte * BITS_PER_UNIT;
7783 if (total_bytes > UNITS_PER_WORD)
7785 word = byte / UNITS_PER_WORD;
7786 if (WORDS_BIG_ENDIAN)
7787 word = (words - 1) - word;
7788 offset = word * UNITS_PER_WORD;
7789 if (BYTES_BIG_ENDIAN)
7790 offset += (UNITS_PER_WORD - 1) - (byte % UNITS_PER_WORD);
7792 offset += byte % UNITS_PER_WORD;
7795 offset = BYTES_BIG_ENDIAN ? (total_bytes - 1) - byte : byte;
7796 value = ptr[offset];
7798 if (bitpos < HOST_BITS_PER_WIDE_INT)
7799 lo |= (unsigned HOST_WIDE_INT) value << bitpos;
7801 hi |= (unsigned HOST_WIDE_INT) value
7802 << (bitpos - HOST_BITS_PER_WIDE_INT);
7805 return build_int_cst_wide_type (type, lo, hi);
7809 /* Subroutine of native_interpret_expr. Interpret the contents of
7810 the buffer PTR of length LEN as a REAL_CST of type TYPE.
7811 If the buffer cannot be interpreted, return NULL_TREE. */
7814 native_interpret_real (tree type, const unsigned char *ptr, int len)
7816 enum machine_mode mode = TYPE_MODE (type);
7817 int total_bytes = GET_MODE_SIZE (mode);
7818 int byte, offset, word, words, bitpos;
7819 unsigned char value;
7820 /* There are always 32 bits in each long, no matter the size of
7821 the hosts long. We handle floating point representations with
7826 total_bytes = GET_MODE_SIZE (TYPE_MODE (type));
7827 if (total_bytes > len || total_bytes > 24)
7829 words = (32 / BITS_PER_UNIT) / UNITS_PER_WORD;
7831 memset (tmp, 0, sizeof (tmp));
7832 for (bitpos = 0; bitpos < total_bytes * BITS_PER_UNIT;
7833 bitpos += BITS_PER_UNIT)
7835 byte = (bitpos / BITS_PER_UNIT) & 3;
7836 if (UNITS_PER_WORD < 4)
7838 word = byte / UNITS_PER_WORD;
7839 if (WORDS_BIG_ENDIAN)
7840 word = (words - 1) - word;
7841 offset = word * UNITS_PER_WORD;
7842 if (BYTES_BIG_ENDIAN)
7843 offset += (UNITS_PER_WORD - 1) - (byte % UNITS_PER_WORD);
7845 offset += byte % UNITS_PER_WORD;
7848 offset = BYTES_BIG_ENDIAN ? 3 - byte : byte;
7849 value = ptr[offset + ((bitpos / BITS_PER_UNIT) & ~3)];
7851 tmp[bitpos / 32] |= (unsigned long)value << (bitpos & 31);
7854 real_from_target (&r, tmp, mode);
7855 return build_real (type, r);
7859 /* Subroutine of native_interpret_expr. Interpret the contents of
7860 the buffer PTR of length LEN as a COMPLEX_CST of type TYPE.
7861 If the buffer cannot be interpreted, return NULL_TREE. */
7864 native_interpret_complex (tree type, const unsigned char *ptr, int len)
7866 tree etype, rpart, ipart;
7869 etype = TREE_TYPE (type);
7870 size = GET_MODE_SIZE (TYPE_MODE (etype));
7873 rpart = native_interpret_expr (etype, ptr, size);
7876 ipart = native_interpret_expr (etype, ptr+size, size);
7879 return build_complex (type, rpart, ipart);
7883 /* Subroutine of native_interpret_expr. Interpret the contents of
7884 the buffer PTR of length LEN as a VECTOR_CST of type TYPE.
7885 If the buffer cannot be interpreted, return NULL_TREE. */
7888 native_interpret_vector (tree type, const unsigned char *ptr, int len)
7890 tree etype, elem, elements;
7893 etype = TREE_TYPE (type);
7894 size = GET_MODE_SIZE (TYPE_MODE (etype));
7895 count = TYPE_VECTOR_SUBPARTS (type);
7896 if (size * count > len)
7899 elements = NULL_TREE;
7900 for (i = count - 1; i >= 0; i--)
7902 elem = native_interpret_expr (etype, ptr+(i*size), size);
7905 elements = tree_cons (NULL_TREE, elem, elements);
7907 return build_vector (type, elements);
7911 /* Subroutine of fold_view_convert_expr. Interpret the contents of
7912 the buffer PTR of length LEN as a constant of type TYPE. For
7913 INTEGRAL_TYPE_P we return an INTEGER_CST, for SCALAR_FLOAT_TYPE_P
7914 we return a REAL_CST, etc... If the buffer cannot be interpreted,
7915 return NULL_TREE. */
7918 native_interpret_expr (tree type, const unsigned char *ptr, int len)
7920 switch (TREE_CODE (type))
7925 return native_interpret_int (type, ptr, len);
7928 return native_interpret_real (type, ptr, len);
7931 return native_interpret_complex (type, ptr, len);
7934 return native_interpret_vector (type, ptr, len);
7942 /* Fold a VIEW_CONVERT_EXPR of a constant expression EXPR to type
7943 TYPE at compile-time. If we're unable to perform the conversion
7944 return NULL_TREE. */
7947 fold_view_convert_expr (tree type, tree expr)
7949 /* We support up to 512-bit values (for V8DFmode). */
7950 unsigned char buffer[64];
7953 /* Check that the host and target are sane. */
7954 if (CHAR_BIT != 8 || BITS_PER_UNIT != 8)
7957 len = native_encode_expr (expr, buffer, sizeof (buffer));
7961 return native_interpret_expr (type, buffer, len);
7964 /* Build an expression for the address of T. Folds away INDIRECT_REF
7965 to avoid confusing the gimplify process. */
7968 build_fold_addr_expr_with_type (tree t, tree ptrtype)
7970 /* The size of the object is not relevant when talking about its address. */
7971 if (TREE_CODE (t) == WITH_SIZE_EXPR)
7972 t = TREE_OPERAND (t, 0);
7974 /* Note: doesn't apply to ALIGN_INDIRECT_REF */
7975 if (TREE_CODE (t) == INDIRECT_REF
7976 || TREE_CODE (t) == MISALIGNED_INDIRECT_REF)
7978 t = TREE_OPERAND (t, 0);
7980 if (TREE_TYPE (t) != ptrtype)
7981 t = build1 (NOP_EXPR, ptrtype, t);
7984 t = build1 (ADDR_EXPR, ptrtype, t);
7989 /* Build an expression for the address of T. */
7992 build_fold_addr_expr (tree t)
7994 tree ptrtype = build_pointer_type (TREE_TYPE (t));
7996 return build_fold_addr_expr_with_type (t, ptrtype);
7999 /* Fold a unary expression of code CODE and type TYPE with operand
8000 OP0. Return the folded expression if folding is successful.
8001 Otherwise, return NULL_TREE. */
8004 fold_unary (enum tree_code code, tree type, tree op0)
8008 enum tree_code_class kind = TREE_CODE_CLASS (code);
8010 gcc_assert (IS_EXPR_CODE_CLASS (kind)
8011 && TREE_CODE_LENGTH (code) == 1);
8016 if (CONVERT_EXPR_CODE_P (code)
8017 || code == FLOAT_EXPR || code == ABS_EXPR)
8019 /* Don't use STRIP_NOPS, because signedness of argument type
8021 STRIP_SIGN_NOPS (arg0);
8025 /* Strip any conversions that don't change the mode. This
8026 is safe for every expression, except for a comparison
8027 expression because its signedness is derived from its
8030 Note that this is done as an internal manipulation within
8031 the constant folder, in order to find the simplest
8032 representation of the arguments so that their form can be
8033 studied. In any cases, the appropriate type conversions
8034 should be put back in the tree that will get out of the
8040 if (TREE_CODE_CLASS (code) == tcc_unary)
8042 if (TREE_CODE (arg0) == COMPOUND_EXPR)
8043 return build2 (COMPOUND_EXPR, type, TREE_OPERAND (arg0, 0),
8044 fold_build1 (code, type,
8045 fold_convert (TREE_TYPE (op0),
8046 TREE_OPERAND (arg0, 1))));
8047 else if (TREE_CODE (arg0) == COND_EXPR)
8049 tree arg01 = TREE_OPERAND (arg0, 1);
8050 tree arg02 = TREE_OPERAND (arg0, 2);
8051 if (! VOID_TYPE_P (TREE_TYPE (arg01)))
8052 arg01 = fold_build1 (code, type,
8053 fold_convert (TREE_TYPE (op0), arg01));
8054 if (! VOID_TYPE_P (TREE_TYPE (arg02)))
8055 arg02 = fold_build1 (code, type,
8056 fold_convert (TREE_TYPE (op0), arg02));
8057 tem = fold_build3 (COND_EXPR, type, TREE_OPERAND (arg0, 0),
8060 /* If this was a conversion, and all we did was to move into
8061 inside the COND_EXPR, bring it back out. But leave it if
8062 it is a conversion from integer to integer and the
8063 result precision is no wider than a word since such a
8064 conversion is cheap and may be optimized away by combine,
8065 while it couldn't if it were outside the COND_EXPR. Then return
8066 so we don't get into an infinite recursion loop taking the
8067 conversion out and then back in. */
8069 if ((CONVERT_EXPR_CODE_P (code)
8070 || code == NON_LVALUE_EXPR)
8071 && TREE_CODE (tem) == COND_EXPR
8072 && TREE_CODE (TREE_OPERAND (tem, 1)) == code
8073 && TREE_CODE (TREE_OPERAND (tem, 2)) == code
8074 && ! VOID_TYPE_P (TREE_OPERAND (tem, 1))
8075 && ! VOID_TYPE_P (TREE_OPERAND (tem, 2))
8076 && (TREE_TYPE (TREE_OPERAND (TREE_OPERAND (tem, 1), 0))
8077 == TREE_TYPE (TREE_OPERAND (TREE_OPERAND (tem, 2), 0)))
8078 && (! (INTEGRAL_TYPE_P (TREE_TYPE (tem))
8080 (TREE_TYPE (TREE_OPERAND (TREE_OPERAND (tem, 1), 0))))
8081 && TYPE_PRECISION (TREE_TYPE (tem)) <= BITS_PER_WORD)
8082 || flag_syntax_only))
8083 tem = build1 (code, type,
8085 TREE_TYPE (TREE_OPERAND
8086 (TREE_OPERAND (tem, 1), 0)),
8087 TREE_OPERAND (tem, 0),
8088 TREE_OPERAND (TREE_OPERAND (tem, 1), 0),
8089 TREE_OPERAND (TREE_OPERAND (tem, 2), 0)));
8092 else if (COMPARISON_CLASS_P (arg0))
8094 if (TREE_CODE (type) == BOOLEAN_TYPE)
8096 arg0 = copy_node (arg0);
8097 TREE_TYPE (arg0) = type;
8100 else if (TREE_CODE (type) != INTEGER_TYPE)
8101 return fold_build3 (COND_EXPR, type, arg0,
8102 fold_build1 (code, type,
8104 fold_build1 (code, type,
8105 integer_zero_node));
8112 /* Re-association barriers around constants and other re-association
8113 barriers can be removed. */
8114 if (CONSTANT_CLASS_P (op0)
8115 || TREE_CODE (op0) == PAREN_EXPR)
8116 return fold_convert (type, op0);
8121 case FIX_TRUNC_EXPR:
8122 if (TREE_TYPE (op0) == type)
8125 /* If we have (type) (a CMP b) and type is an integral type, return
8126 new expression involving the new type. */
8127 if (COMPARISON_CLASS_P (op0) && INTEGRAL_TYPE_P (type))
8128 return fold_build2 (TREE_CODE (op0), type, TREE_OPERAND (op0, 0),
8129 TREE_OPERAND (op0, 1));
8131 /* Handle cases of two conversions in a row. */
8132 if (CONVERT_EXPR_P (op0))
8134 tree inside_type = TREE_TYPE (TREE_OPERAND (op0, 0));
8135 tree inter_type = TREE_TYPE (op0);
8136 int inside_int = INTEGRAL_TYPE_P (inside_type);
8137 int inside_ptr = POINTER_TYPE_P (inside_type);
8138 int inside_float = FLOAT_TYPE_P (inside_type);
8139 int inside_vec = TREE_CODE (inside_type) == VECTOR_TYPE;
8140 unsigned int inside_prec = TYPE_PRECISION (inside_type);
8141 int inside_unsignedp = TYPE_UNSIGNED (inside_type);
8142 int inter_int = INTEGRAL_TYPE_P (inter_type);
8143 int inter_ptr = POINTER_TYPE_P (inter_type);
8144 int inter_float = FLOAT_TYPE_P (inter_type);
8145 int inter_vec = TREE_CODE (inter_type) == VECTOR_TYPE;
8146 unsigned int inter_prec = TYPE_PRECISION (inter_type);
8147 int inter_unsignedp = TYPE_UNSIGNED (inter_type);
8148 int final_int = INTEGRAL_TYPE_P (type);
8149 int final_ptr = POINTER_TYPE_P (type);
8150 int final_float = FLOAT_TYPE_P (type);
8151 int final_vec = TREE_CODE (type) == VECTOR_TYPE;
8152 unsigned int final_prec = TYPE_PRECISION (type);
8153 int final_unsignedp = TYPE_UNSIGNED (type);
8155 /* In addition to the cases of two conversions in a row
8156 handled below, if we are converting something to its own
8157 type via an object of identical or wider precision, neither
8158 conversion is needed. */
8159 if (TYPE_MAIN_VARIANT (inside_type) == TYPE_MAIN_VARIANT (type)
8160 && (((inter_int || inter_ptr) && final_int)
8161 || (inter_float && final_float))
8162 && inter_prec >= final_prec)
8163 return fold_build1 (code, type, TREE_OPERAND (op0, 0));
8165 /* Likewise, if the intermediate and initial types are either both
8166 float or both integer, we don't need the middle conversion if the
8167 former is wider than the latter and doesn't change the signedness
8168 (for integers). Avoid this if the final type is a pointer since
8169 then we sometimes need the middle conversion. Likewise if the
8170 final type has a precision not equal to the size of its mode. */
8171 if (((inter_int && inside_int)
8172 || (inter_float && inside_float)
8173 || (inter_vec && inside_vec))
8174 && inter_prec >= inside_prec
8175 && (inter_float || inter_vec
8176 || inter_unsignedp == inside_unsignedp)
8177 && ! (final_prec != GET_MODE_BITSIZE (TYPE_MODE (type))
8178 && TYPE_MODE (type) == TYPE_MODE (inter_type))
8180 && (! final_vec || inter_prec == inside_prec))
8181 return fold_build1 (code, type, TREE_OPERAND (op0, 0));
8183 /* If we have a sign-extension of a zero-extended value, we can
8184 replace that by a single zero-extension. */
8185 if (inside_int && inter_int && final_int
8186 && inside_prec < inter_prec && inter_prec < final_prec
8187 && inside_unsignedp && !inter_unsignedp)
8188 return fold_build1 (code, type, TREE_OPERAND (op0, 0));
8190 /* Two conversions in a row are not needed unless:
8191 - some conversion is floating-point (overstrict for now), or
8192 - some conversion is a vector (overstrict for now), or
8193 - the intermediate type is narrower than both initial and
8195 - the intermediate type and innermost type differ in signedness,
8196 and the outermost type is wider than the intermediate, or
8197 - the initial type is a pointer type and the precisions of the
8198 intermediate and final types differ, or
8199 - the final type is a pointer type and the precisions of the
8200 initial and intermediate types differ. */
8201 if (! inside_float && ! inter_float && ! final_float
8202 && ! inside_vec && ! inter_vec && ! final_vec
8203 && (inter_prec >= inside_prec || inter_prec >= final_prec)
8204 && ! (inside_int && inter_int
8205 && inter_unsignedp != inside_unsignedp
8206 && inter_prec < final_prec)
8207 && ((inter_unsignedp && inter_prec > inside_prec)
8208 == (final_unsignedp && final_prec > inter_prec))
8209 && ! (inside_ptr && inter_prec != final_prec)
8210 && ! (final_ptr && inside_prec != inter_prec)
8211 && ! (final_prec != GET_MODE_BITSIZE (TYPE_MODE (type))
8212 && TYPE_MODE (type) == TYPE_MODE (inter_type)))
8213 return fold_build1 (code, type, TREE_OPERAND (op0, 0));
8216 /* Handle (T *)&A.B.C for A being of type T and B and C
8217 living at offset zero. This occurs frequently in
8218 C++ upcasting and then accessing the base. */
8219 if (TREE_CODE (op0) == ADDR_EXPR
8220 && POINTER_TYPE_P (type)
8221 && handled_component_p (TREE_OPERAND (op0, 0)))
8223 HOST_WIDE_INT bitsize, bitpos;
8225 enum machine_mode mode;
8226 int unsignedp, volatilep;
8227 tree base = TREE_OPERAND (op0, 0);
8228 base = get_inner_reference (base, &bitsize, &bitpos, &offset,
8229 &mode, &unsignedp, &volatilep, false);
8230 /* If the reference was to a (constant) zero offset, we can use
8231 the address of the base if it has the same base type
8232 as the result type. */
8233 if (! offset && bitpos == 0
8234 && TYPE_MAIN_VARIANT (TREE_TYPE (type))
8235 == TYPE_MAIN_VARIANT (TREE_TYPE (base)))
8236 return fold_convert (type, build_fold_addr_expr (base));
8239 if (TREE_CODE (op0) == MODIFY_EXPR
8240 && TREE_CONSTANT (TREE_OPERAND (op0, 1))
8241 /* Detect assigning a bitfield. */
8242 && !(TREE_CODE (TREE_OPERAND (op0, 0)) == COMPONENT_REF
8244 (TREE_OPERAND (TREE_OPERAND (op0, 0), 1))))
8246 /* Don't leave an assignment inside a conversion
8247 unless assigning a bitfield. */
8248 tem = fold_build1 (code, type, TREE_OPERAND (op0, 1));
8249 /* First do the assignment, then return converted constant. */
8250 tem = build2 (COMPOUND_EXPR, TREE_TYPE (tem), op0, tem);
8251 TREE_NO_WARNING (tem) = 1;
8252 TREE_USED (tem) = 1;
8256 /* Convert (T)(x & c) into (T)x & (T)c, if c is an integer
8257 constants (if x has signed type, the sign bit cannot be set
8258 in c). This folds extension into the BIT_AND_EXPR.
8259 ??? We don't do it for BOOLEAN_TYPE or ENUMERAL_TYPE because they
8260 very likely don't have maximal range for their precision and this
8261 transformation effectively doesn't preserve non-maximal ranges. */
8262 if (TREE_CODE (type) == INTEGER_TYPE
8263 && TREE_CODE (op0) == BIT_AND_EXPR
8264 && TREE_CODE (TREE_OPERAND (op0, 1)) == INTEGER_CST
8265 /* Not if the conversion is to the sub-type. */
8266 && TREE_TYPE (type) != TREE_TYPE (op0))
8269 tree and0 = TREE_OPERAND (and, 0), and1 = TREE_OPERAND (and, 1);
8272 if (TYPE_UNSIGNED (TREE_TYPE (and))
8273 || (TYPE_PRECISION (type)
8274 <= TYPE_PRECISION (TREE_TYPE (and))))
8276 else if (TYPE_PRECISION (TREE_TYPE (and1))
8277 <= HOST_BITS_PER_WIDE_INT
8278 && host_integerp (and1, 1))
8280 unsigned HOST_WIDE_INT cst;
8282 cst = tree_low_cst (and1, 1);
8283 cst &= (HOST_WIDE_INT) -1
8284 << (TYPE_PRECISION (TREE_TYPE (and1)) - 1);
8285 change = (cst == 0);
8286 #ifdef LOAD_EXTEND_OP
8288 && !flag_syntax_only
8289 && (LOAD_EXTEND_OP (TYPE_MODE (TREE_TYPE (and0)))
8292 tree uns = unsigned_type_for (TREE_TYPE (and0));
8293 and0 = fold_convert (uns, and0);
8294 and1 = fold_convert (uns, and1);
8300 tem = force_fit_type_double (type, TREE_INT_CST_LOW (and1),
8301 TREE_INT_CST_HIGH (and1), 0,
8302 TREE_OVERFLOW (and1));
8303 return fold_build2 (BIT_AND_EXPR, type,
8304 fold_convert (type, and0), tem);
8308 /* Convert (T1)(X p+ Y) into ((T1)X p+ Y), for pointer type,
8309 when one of the new casts will fold away. Conservatively we assume
8310 that this happens when X or Y is NOP_EXPR or Y is INTEGER_CST. */
8311 if (POINTER_TYPE_P (type)
8312 && TREE_CODE (arg0) == POINTER_PLUS_EXPR
8313 && (TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST
8314 || TREE_CODE (TREE_OPERAND (arg0, 0)) == NOP_EXPR
8315 || TREE_CODE (TREE_OPERAND (arg0, 1)) == NOP_EXPR))
8317 tree arg00 = TREE_OPERAND (arg0, 0);
8318 tree arg01 = TREE_OPERAND (arg0, 1);
8320 return fold_build2 (TREE_CODE (arg0), type, fold_convert (type, arg00),
8321 fold_convert (sizetype, arg01));
8324 /* Convert (T1)(~(T2)X) into ~(T1)X if T1 and T2 are integral types
8325 of the same precision, and X is an integer type not narrower than
8326 types T1 or T2, i.e. the cast (T2)X isn't an extension. */
8327 if (INTEGRAL_TYPE_P (type)
8328 && TREE_CODE (op0) == BIT_NOT_EXPR
8329 && INTEGRAL_TYPE_P (TREE_TYPE (op0))
8330 && CONVERT_EXPR_P (TREE_OPERAND (op0, 0))
8331 && TYPE_PRECISION (type) == TYPE_PRECISION (TREE_TYPE (op0)))
8333 tem = TREE_OPERAND (TREE_OPERAND (op0, 0), 0);
8334 if (INTEGRAL_TYPE_P (TREE_TYPE (tem))
8335 && TYPE_PRECISION (type) <= TYPE_PRECISION (TREE_TYPE (tem)))
8336 return fold_build1 (BIT_NOT_EXPR, type, fold_convert (type, tem));
8339 /* Convert (T1)(X * Y) into (T1)X * (T1)Y if T1 is narrower than the
8340 type of X and Y (integer types only). */
8341 if (INTEGRAL_TYPE_P (type)
8342 && TREE_CODE (op0) == MULT_EXPR
8343 && INTEGRAL_TYPE_P (TREE_TYPE (op0))
8344 && TYPE_PRECISION (type) < TYPE_PRECISION (TREE_TYPE (op0)))
8346 /* Be careful not to introduce new overflows. */
8348 if (TYPE_OVERFLOW_WRAPS (type))
8351 mult_type = unsigned_type_for (type);
8353 if (TYPE_PRECISION (mult_type) < TYPE_PRECISION (TREE_TYPE (op0)))
8355 tem = fold_build2 (MULT_EXPR, mult_type,
8356 fold_convert (mult_type,
8357 TREE_OPERAND (op0, 0)),
8358 fold_convert (mult_type,
8359 TREE_OPERAND (op0, 1)));
8360 return fold_convert (type, tem);
8364 tem = fold_convert_const (code, type, op0);
8365 return tem ? tem : NULL_TREE;
8367 case FIXED_CONVERT_EXPR:
8368 tem = fold_convert_const (code, type, arg0);
8369 return tem ? tem : NULL_TREE;
8371 case VIEW_CONVERT_EXPR:
8372 if (TREE_TYPE (op0) == type)
8374 if (TREE_CODE (op0) == VIEW_CONVERT_EXPR)
8375 return fold_build1 (VIEW_CONVERT_EXPR, type, TREE_OPERAND (op0, 0));
8377 /* For integral conversions with the same precision or pointer
8378 conversions use a NOP_EXPR instead. */
8379 if ((INTEGRAL_TYPE_P (type)
8380 || POINTER_TYPE_P (type))
8381 && (INTEGRAL_TYPE_P (TREE_TYPE (op0))
8382 || POINTER_TYPE_P (TREE_TYPE (op0)))
8383 && TYPE_PRECISION (type) == TYPE_PRECISION (TREE_TYPE (op0))
8384 /* Do not muck with VIEW_CONVERT_EXPRs that convert from
8385 a sub-type to its base type as generated by the Ada FE. */
8386 && !(INTEGRAL_TYPE_P (TREE_TYPE (op0))
8387 && TREE_TYPE (TREE_TYPE (op0))))
8388 return fold_convert (type, op0);
8390 /* Strip inner integral conversions that do not change the precision. */
8391 if (CONVERT_EXPR_P (op0)
8392 && (INTEGRAL_TYPE_P (TREE_TYPE (op0))
8393 || POINTER_TYPE_P (TREE_TYPE (op0)))
8394 && (INTEGRAL_TYPE_P (TREE_TYPE (TREE_OPERAND (op0, 0)))
8395 || POINTER_TYPE_P (TREE_TYPE (TREE_OPERAND (op0, 0))))
8396 && (TYPE_PRECISION (TREE_TYPE (op0))
8397 == TYPE_PRECISION (TREE_TYPE (TREE_OPERAND (op0, 0)))))
8398 return fold_build1 (VIEW_CONVERT_EXPR, type, TREE_OPERAND (op0, 0));
8400 return fold_view_convert_expr (type, op0);
8403 tem = fold_negate_expr (arg0);
8405 return fold_convert (type, tem);
8409 if (TREE_CODE (arg0) == INTEGER_CST || TREE_CODE (arg0) == REAL_CST)
8410 return fold_abs_const (arg0, type);
8411 else if (TREE_CODE (arg0) == NEGATE_EXPR)
8412 return fold_build1 (ABS_EXPR, type, TREE_OPERAND (arg0, 0));
8413 /* Convert fabs((double)float) into (double)fabsf(float). */
8414 else if (TREE_CODE (arg0) == NOP_EXPR
8415 && TREE_CODE (type) == REAL_TYPE)
8417 tree targ0 = strip_float_extensions (arg0);
8419 return fold_convert (type, fold_build1 (ABS_EXPR,
8423 /* ABS_EXPR<ABS_EXPR<x>> = ABS_EXPR<x> even if flag_wrapv is on. */
8424 else if (TREE_CODE (arg0) == ABS_EXPR)
8426 else if (tree_expr_nonnegative_p (arg0))
8429 /* Strip sign ops from argument. */
8430 if (TREE_CODE (type) == REAL_TYPE)
8432 tem = fold_strip_sign_ops (arg0);
8434 return fold_build1 (ABS_EXPR, type, fold_convert (type, tem));
8439 if (TREE_CODE (TREE_TYPE (arg0)) != COMPLEX_TYPE)
8440 return fold_convert (type, arg0);
8441 if (TREE_CODE (arg0) == COMPLEX_EXPR)
8443 tree itype = TREE_TYPE (type);
8444 tree rpart = fold_convert (itype, TREE_OPERAND (arg0, 0));
8445 tree ipart = fold_convert (itype, TREE_OPERAND (arg0, 1));
8446 return fold_build2 (COMPLEX_EXPR, type, rpart, negate_expr (ipart));
8448 if (TREE_CODE (arg0) == COMPLEX_CST)
8450 tree itype = TREE_TYPE (type);
8451 tree rpart = fold_convert (itype, TREE_REALPART (arg0));
8452 tree ipart = fold_convert (itype, TREE_IMAGPART (arg0));
8453 return build_complex (type, rpart, negate_expr (ipart));
8455 if (TREE_CODE (arg0) == CONJ_EXPR)
8456 return fold_convert (type, TREE_OPERAND (arg0, 0));
8460 if (TREE_CODE (arg0) == INTEGER_CST)
8461 return fold_not_const (arg0, type);
8462 else if (TREE_CODE (arg0) == BIT_NOT_EXPR)
8463 return fold_convert (type, TREE_OPERAND (arg0, 0));
8464 /* Convert ~ (-A) to A - 1. */
8465 else if (INTEGRAL_TYPE_P (type) && TREE_CODE (arg0) == NEGATE_EXPR)
8466 return fold_build2 (MINUS_EXPR, type,
8467 fold_convert (type, TREE_OPERAND (arg0, 0)),
8468 build_int_cst (type, 1));
8469 /* Convert ~ (A - 1) or ~ (A + -1) to -A. */
8470 else if (INTEGRAL_TYPE_P (type)
8471 && ((TREE_CODE (arg0) == MINUS_EXPR
8472 && integer_onep (TREE_OPERAND (arg0, 1)))
8473 || (TREE_CODE (arg0) == PLUS_EXPR
8474 && integer_all_onesp (TREE_OPERAND (arg0, 1)))))
8475 return fold_build1 (NEGATE_EXPR, type,
8476 fold_convert (type, TREE_OPERAND (arg0, 0)));
8477 /* Convert ~(X ^ Y) to ~X ^ Y or X ^ ~Y if ~X or ~Y simplify. */
8478 else if (TREE_CODE (arg0) == BIT_XOR_EXPR
8479 && (tem = fold_unary (BIT_NOT_EXPR, type,
8481 TREE_OPERAND (arg0, 0)))))
8482 return fold_build2 (BIT_XOR_EXPR, type, tem,
8483 fold_convert (type, TREE_OPERAND (arg0, 1)));
8484 else if (TREE_CODE (arg0) == BIT_XOR_EXPR
8485 && (tem = fold_unary (BIT_NOT_EXPR, type,
8487 TREE_OPERAND (arg0, 1)))))
8488 return fold_build2 (BIT_XOR_EXPR, type,
8489 fold_convert (type, TREE_OPERAND (arg0, 0)), tem);
8490 /* Perform BIT_NOT_EXPR on each element individually. */
8491 else if (TREE_CODE (arg0) == VECTOR_CST)
8493 tree elements = TREE_VECTOR_CST_ELTS (arg0), elem, list = NULL_TREE;
8494 int count = TYPE_VECTOR_SUBPARTS (type), i;
8496 for (i = 0; i < count; i++)
8500 elem = TREE_VALUE (elements);
8501 elem = fold_unary (BIT_NOT_EXPR, TREE_TYPE (type), elem);
8502 if (elem == NULL_TREE)
8504 elements = TREE_CHAIN (elements);
8507 elem = build_int_cst (TREE_TYPE (type), -1);
8508 list = tree_cons (NULL_TREE, elem, list);
8511 return build_vector (type, nreverse (list));
8516 case TRUTH_NOT_EXPR:
8517 /* The argument to invert_truthvalue must have Boolean type. */
8518 if (TREE_CODE (TREE_TYPE (arg0)) != BOOLEAN_TYPE)
8519 arg0 = fold_convert (boolean_type_node, arg0);
8521 /* Note that the operand of this must be an int
8522 and its values must be 0 or 1.
8523 ("true" is a fixed value perhaps depending on the language,
8524 but we don't handle values other than 1 correctly yet.) */
8525 tem = fold_truth_not_expr (arg0);
8528 return fold_convert (type, tem);
8531 if (TREE_CODE (TREE_TYPE (arg0)) != COMPLEX_TYPE)
8532 return fold_convert (type, arg0);
8533 if (TREE_CODE (arg0) == COMPLEX_EXPR)
8534 return omit_one_operand (type, TREE_OPERAND (arg0, 0),
8535 TREE_OPERAND (arg0, 1));
8536 if (TREE_CODE (arg0) == COMPLEX_CST)
8537 return fold_convert (type, TREE_REALPART (arg0));
8538 if (TREE_CODE (arg0) == PLUS_EXPR || TREE_CODE (arg0) == MINUS_EXPR)
8540 tree itype = TREE_TYPE (TREE_TYPE (arg0));
8541 tem = fold_build2 (TREE_CODE (arg0), itype,
8542 fold_build1 (REALPART_EXPR, itype,
8543 TREE_OPERAND (arg0, 0)),
8544 fold_build1 (REALPART_EXPR, itype,
8545 TREE_OPERAND (arg0, 1)));
8546 return fold_convert (type, tem);
8548 if (TREE_CODE (arg0) == CONJ_EXPR)
8550 tree itype = TREE_TYPE (TREE_TYPE (arg0));
8551 tem = fold_build1 (REALPART_EXPR, itype, TREE_OPERAND (arg0, 0));
8552 return fold_convert (type, tem);
8554 if (TREE_CODE (arg0) == CALL_EXPR)
8556 tree fn = get_callee_fndecl (arg0);
8557 if (fn && DECL_BUILT_IN_CLASS (fn) == BUILT_IN_NORMAL)
8558 switch (DECL_FUNCTION_CODE (fn))
8560 CASE_FLT_FN (BUILT_IN_CEXPI):
8561 fn = mathfn_built_in (type, BUILT_IN_COS);
8563 return build_call_expr (fn, 1, CALL_EXPR_ARG (arg0, 0));
8573 if (TREE_CODE (TREE_TYPE (arg0)) != COMPLEX_TYPE)
8574 return fold_convert (type, integer_zero_node);
8575 if (TREE_CODE (arg0) == COMPLEX_EXPR)
8576 return omit_one_operand (type, TREE_OPERAND (arg0, 1),
8577 TREE_OPERAND (arg0, 0));
8578 if (TREE_CODE (arg0) == COMPLEX_CST)
8579 return fold_convert (type, TREE_IMAGPART (arg0));
8580 if (TREE_CODE (arg0) == PLUS_EXPR || TREE_CODE (arg0) == MINUS_EXPR)
8582 tree itype = TREE_TYPE (TREE_TYPE (arg0));
8583 tem = fold_build2 (TREE_CODE (arg0), itype,
8584 fold_build1 (IMAGPART_EXPR, itype,
8585 TREE_OPERAND (arg0, 0)),
8586 fold_build1 (IMAGPART_EXPR, itype,
8587 TREE_OPERAND (arg0, 1)));
8588 return fold_convert (type, tem);
8590 if (TREE_CODE (arg0) == CONJ_EXPR)
8592 tree itype = TREE_TYPE (TREE_TYPE (arg0));
8593 tem = fold_build1 (IMAGPART_EXPR, itype, TREE_OPERAND (arg0, 0));
8594 return fold_convert (type, negate_expr (tem));
8596 if (TREE_CODE (arg0) == CALL_EXPR)
8598 tree fn = get_callee_fndecl (arg0);
8599 if (fn && DECL_BUILT_IN_CLASS (fn) == BUILT_IN_NORMAL)
8600 switch (DECL_FUNCTION_CODE (fn))
8602 CASE_FLT_FN (BUILT_IN_CEXPI):
8603 fn = mathfn_built_in (type, BUILT_IN_SIN);
8605 return build_call_expr (fn, 1, CALL_EXPR_ARG (arg0, 0));
8616 } /* switch (code) */
8620 /* If the operation was a conversion do _not_ mark a resulting constant
8621 with TREE_OVERFLOW if the original constant was not. These conversions
8622 have implementation defined behavior and retaining the TREE_OVERFLOW
8623 flag here would confuse later passes such as VRP. */
8625 fold_unary_ignore_overflow (enum tree_code code, tree type, tree op0)
8627 tree res = fold_unary (code, type, op0);
8629 && TREE_CODE (res) == INTEGER_CST
8630 && TREE_CODE (op0) == INTEGER_CST
8631 && CONVERT_EXPR_CODE_P (code))
8632 TREE_OVERFLOW (res) = TREE_OVERFLOW (op0);
8637 /* Fold a binary expression of code CODE and type TYPE with operands
8638 OP0 and OP1, containing either a MIN-MAX or a MAX-MIN combination.
8639 Return the folded expression if folding is successful. Otherwise,
8640 return NULL_TREE. */
8643 fold_minmax (enum tree_code code, tree type, tree op0, tree op1)
8645 enum tree_code compl_code;
8647 if (code == MIN_EXPR)
8648 compl_code = MAX_EXPR;
8649 else if (code == MAX_EXPR)
8650 compl_code = MIN_EXPR;
8654 /* MIN (MAX (a, b), b) == b. */
8655 if (TREE_CODE (op0) == compl_code
8656 && operand_equal_p (TREE_OPERAND (op0, 1), op1, 0))
8657 return omit_one_operand (type, op1, TREE_OPERAND (op0, 0));
8659 /* MIN (MAX (b, a), b) == b. */
8660 if (TREE_CODE (op0) == compl_code
8661 && operand_equal_p (TREE_OPERAND (op0, 0), op1, 0)
8662 && reorder_operands_p (TREE_OPERAND (op0, 1), op1))
8663 return omit_one_operand (type, op1, TREE_OPERAND (op0, 1));
8665 /* MIN (a, MAX (a, b)) == a. */
8666 if (TREE_CODE (op1) == compl_code
8667 && operand_equal_p (op0, TREE_OPERAND (op1, 0), 0)
8668 && reorder_operands_p (op0, TREE_OPERAND (op1, 1)))
8669 return omit_one_operand (type, op0, TREE_OPERAND (op1, 1));
8671 /* MIN (a, MAX (b, a)) == a. */
8672 if (TREE_CODE (op1) == compl_code
8673 && operand_equal_p (op0, TREE_OPERAND (op1, 1), 0)
8674 && reorder_operands_p (op0, TREE_OPERAND (op1, 0)))
8675 return omit_one_operand (type, op0, TREE_OPERAND (op1, 0));
8680 /* Helper that tries to canonicalize the comparison ARG0 CODE ARG1
8681 by changing CODE to reduce the magnitude of constants involved in
8682 ARG0 of the comparison.
8683 Returns a canonicalized comparison tree if a simplification was
8684 possible, otherwise returns NULL_TREE.
8685 Set *STRICT_OVERFLOW_P to true if the canonicalization is only
8686 valid if signed overflow is undefined. */
8689 maybe_canonicalize_comparison_1 (enum tree_code code, tree type,
8690 tree arg0, tree arg1,
8691 bool *strict_overflow_p)
8693 enum tree_code code0 = TREE_CODE (arg0);
8694 tree t, cst0 = NULL_TREE;
8698 /* Match A +- CST code arg1 and CST code arg1. We can change the
8699 first form only if overflow is undefined. */
8700 if (!((TYPE_OVERFLOW_UNDEFINED (TREE_TYPE (arg0))
8701 /* In principle pointers also have undefined overflow behavior,
8702 but that causes problems elsewhere. */
8703 && !POINTER_TYPE_P (TREE_TYPE (arg0))
8704 && (code0 == MINUS_EXPR
8705 || code0 == PLUS_EXPR)
8706 && TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST)
8707 || code0 == INTEGER_CST))
8710 /* Identify the constant in arg0 and its sign. */
8711 if (code0 == INTEGER_CST)
8714 cst0 = TREE_OPERAND (arg0, 1);
8715 sgn0 = tree_int_cst_sgn (cst0);
8717 /* Overflowed constants and zero will cause problems. */
8718 if (integer_zerop (cst0)
8719 || TREE_OVERFLOW (cst0))
8722 /* See if we can reduce the magnitude of the constant in
8723 arg0 by changing the comparison code. */
8724 if (code0 == INTEGER_CST)
8726 /* CST <= arg1 -> CST-1 < arg1. */
8727 if (code == LE_EXPR && sgn0 == 1)
8729 /* -CST < arg1 -> -CST-1 <= arg1. */
8730 else if (code == LT_EXPR && sgn0 == -1)
8732 /* CST > arg1 -> CST-1 >= arg1. */
8733 else if (code == GT_EXPR && sgn0 == 1)
8735 /* -CST >= arg1 -> -CST-1 > arg1. */
8736 else if (code == GE_EXPR && sgn0 == -1)
8740 /* arg1 code' CST' might be more canonical. */
8745 /* A - CST < arg1 -> A - CST-1 <= arg1. */
8747 && code0 == ((sgn0 == -1) ? PLUS_EXPR : MINUS_EXPR))
8749 /* A + CST > arg1 -> A + CST-1 >= arg1. */
8750 else if (code == GT_EXPR
8751 && code0 == ((sgn0 == -1) ? MINUS_EXPR : PLUS_EXPR))
8753 /* A + CST <= arg1 -> A + CST-1 < arg1. */
8754 else if (code == LE_EXPR
8755 && code0 == ((sgn0 == -1) ? MINUS_EXPR : PLUS_EXPR))
8757 /* A - CST >= arg1 -> A - CST-1 > arg1. */
8758 else if (code == GE_EXPR
8759 && code0 == ((sgn0 == -1) ? PLUS_EXPR : MINUS_EXPR))
8763 *strict_overflow_p = true;
8766 /* Now build the constant reduced in magnitude. But not if that
8767 would produce one outside of its types range. */
8768 if (INTEGRAL_TYPE_P (TREE_TYPE (cst0))
8770 && TYPE_MIN_VALUE (TREE_TYPE (cst0))
8771 && tree_int_cst_equal (cst0, TYPE_MIN_VALUE (TREE_TYPE (cst0))))
8773 && TYPE_MAX_VALUE (TREE_TYPE (cst0))
8774 && tree_int_cst_equal (cst0, TYPE_MAX_VALUE (TREE_TYPE (cst0))))))
8775 /* We cannot swap the comparison here as that would cause us to
8776 endlessly recurse. */
8779 t = int_const_binop (sgn0 == -1 ? PLUS_EXPR : MINUS_EXPR,
8780 cst0, build_int_cst (TREE_TYPE (cst0), 1), 0);
8781 if (code0 != INTEGER_CST)
8782 t = fold_build2 (code0, TREE_TYPE (arg0), TREE_OPERAND (arg0, 0), t);
8784 /* If swapping might yield to a more canonical form, do so. */
8786 return fold_build2 (swap_tree_comparison (code), type, arg1, t);
8788 return fold_build2 (code, type, t, arg1);
8791 /* Canonicalize the comparison ARG0 CODE ARG1 with type TYPE with undefined
8792 overflow further. Try to decrease the magnitude of constants involved
8793 by changing LE_EXPR and GE_EXPR to LT_EXPR and GT_EXPR or vice versa
8794 and put sole constants at the second argument position.
8795 Returns the canonicalized tree if changed, otherwise NULL_TREE. */
8798 maybe_canonicalize_comparison (enum tree_code code, tree type,
8799 tree arg0, tree arg1)
8802 bool strict_overflow_p;
8803 const char * const warnmsg = G_("assuming signed overflow does not occur "
8804 "when reducing constant in comparison");
8806 /* Try canonicalization by simplifying arg0. */
8807 strict_overflow_p = false;
8808 t = maybe_canonicalize_comparison_1 (code, type, arg0, arg1,
8809 &strict_overflow_p);
8812 if (strict_overflow_p)
8813 fold_overflow_warning (warnmsg, WARN_STRICT_OVERFLOW_MAGNITUDE);
8817 /* Try canonicalization by simplifying arg1 using the swapped
8819 code = swap_tree_comparison (code);
8820 strict_overflow_p = false;
8821 t = maybe_canonicalize_comparison_1 (code, type, arg1, arg0,
8822 &strict_overflow_p);
8823 if (t && strict_overflow_p)
8824 fold_overflow_warning (warnmsg, WARN_STRICT_OVERFLOW_MAGNITUDE);
8828 /* Return whether BASE + OFFSET + BITPOS may wrap around the address
8829 space. This is used to avoid issuing overflow warnings for
8830 expressions like &p->x which can not wrap. */
8833 pointer_may_wrap_p (tree base, tree offset, HOST_WIDE_INT bitpos)
8835 unsigned HOST_WIDE_INT offset_low, total_low;
8836 HOST_WIDE_INT size, offset_high, total_high;
8838 if (!POINTER_TYPE_P (TREE_TYPE (base)))
8844 if (offset == NULL_TREE)
8849 else if (TREE_CODE (offset) != INTEGER_CST || TREE_OVERFLOW (offset))
8853 offset_low = TREE_INT_CST_LOW (offset);
8854 offset_high = TREE_INT_CST_HIGH (offset);
8857 if (add_double_with_sign (offset_low, offset_high,
8858 bitpos / BITS_PER_UNIT, 0,
8859 &total_low, &total_high,
8863 if (total_high != 0)
8866 size = int_size_in_bytes (TREE_TYPE (TREE_TYPE (base)));
8870 /* We can do slightly better for SIZE if we have an ADDR_EXPR of an
8872 if (TREE_CODE (base) == ADDR_EXPR)
8874 HOST_WIDE_INT base_size;
8876 base_size = int_size_in_bytes (TREE_TYPE (TREE_OPERAND (base, 0)));
8877 if (base_size > 0 && size < base_size)
8881 return total_low > (unsigned HOST_WIDE_INT) size;
8884 /* Subroutine of fold_binary. This routine performs all of the
8885 transformations that are common to the equality/inequality
8886 operators (EQ_EXPR and NE_EXPR) and the ordering operators
8887 (LT_EXPR, LE_EXPR, GE_EXPR and GT_EXPR). Callers other than
8888 fold_binary should call fold_binary. Fold a comparison with
8889 tree code CODE and type TYPE with operands OP0 and OP1. Return
8890 the folded comparison or NULL_TREE. */
8893 fold_comparison (enum tree_code code, tree type, tree op0, tree op1)
8895 tree arg0, arg1, tem;
8900 STRIP_SIGN_NOPS (arg0);
8901 STRIP_SIGN_NOPS (arg1);
8903 tem = fold_relational_const (code, type, arg0, arg1);
8904 if (tem != NULL_TREE)
8907 /* If one arg is a real or integer constant, put it last. */
8908 if (tree_swap_operands_p (arg0, arg1, true))
8909 return fold_build2 (swap_tree_comparison (code), type, op1, op0);
8911 /* Transform comparisons of the form X +- C1 CMP C2 to X CMP C2 +- C1. */
8912 if ((TREE_CODE (arg0) == PLUS_EXPR || TREE_CODE (arg0) == MINUS_EXPR)
8913 && (TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST
8914 && !TREE_OVERFLOW (TREE_OPERAND (arg0, 1))
8915 && TYPE_OVERFLOW_UNDEFINED (TREE_TYPE (arg1)))
8916 && (TREE_CODE (arg1) == INTEGER_CST
8917 && !TREE_OVERFLOW (arg1)))
8919 tree const1 = TREE_OPERAND (arg0, 1);
8921 tree variable = TREE_OPERAND (arg0, 0);
8924 lhs_add = TREE_CODE (arg0) != PLUS_EXPR;
8926 lhs = fold_build2 (lhs_add ? PLUS_EXPR : MINUS_EXPR,
8927 TREE_TYPE (arg1), const2, const1);
8929 /* If the constant operation overflowed this can be
8930 simplified as a comparison against INT_MAX/INT_MIN. */
8931 if (TREE_CODE (lhs) == INTEGER_CST
8932 && TREE_OVERFLOW (lhs))
8934 int const1_sgn = tree_int_cst_sgn (const1);
8935 enum tree_code code2 = code;
8937 /* Get the sign of the constant on the lhs if the
8938 operation were VARIABLE + CONST1. */
8939 if (TREE_CODE (arg0) == MINUS_EXPR)
8940 const1_sgn = -const1_sgn;
8942 /* The sign of the constant determines if we overflowed
8943 INT_MAX (const1_sgn == -1) or INT_MIN (const1_sgn == 1).
8944 Canonicalize to the INT_MIN overflow by swapping the comparison
8946 if (const1_sgn == -1)
8947 code2 = swap_tree_comparison (code);
8949 /* We now can look at the canonicalized case
8950 VARIABLE + 1 CODE2 INT_MIN
8951 and decide on the result. */
8952 if (code2 == LT_EXPR
8954 || code2 == EQ_EXPR)
8955 return omit_one_operand (type, boolean_false_node, variable);
8956 else if (code2 == NE_EXPR
8958 || code2 == GT_EXPR)
8959 return omit_one_operand (type, boolean_true_node, variable);
8962 if (TREE_CODE (lhs) == TREE_CODE (arg1)
8963 && (TREE_CODE (lhs) != INTEGER_CST
8964 || !TREE_OVERFLOW (lhs)))
8966 fold_overflow_warning (("assuming signed overflow does not occur "
8967 "when changing X +- C1 cmp C2 to "
8969 WARN_STRICT_OVERFLOW_COMPARISON);
8970 return fold_build2 (code, type, variable, lhs);
8974 /* For comparisons of pointers we can decompose it to a compile time
8975 comparison of the base objects and the offsets into the object.
8976 This requires at least one operand being an ADDR_EXPR or a
8977 POINTER_PLUS_EXPR to do more than the operand_equal_p test below. */
8978 if (POINTER_TYPE_P (TREE_TYPE (arg0))
8979 && (TREE_CODE (arg0) == ADDR_EXPR
8980 || TREE_CODE (arg1) == ADDR_EXPR
8981 || TREE_CODE (arg0) == POINTER_PLUS_EXPR
8982 || TREE_CODE (arg1) == POINTER_PLUS_EXPR))
8984 tree base0, base1, offset0 = NULL_TREE, offset1 = NULL_TREE;
8985 HOST_WIDE_INT bitsize, bitpos0 = 0, bitpos1 = 0;
8986 enum machine_mode mode;
8987 int volatilep, unsignedp;
8988 bool indirect_base0 = false, indirect_base1 = false;
8990 /* Get base and offset for the access. Strip ADDR_EXPR for
8991 get_inner_reference, but put it back by stripping INDIRECT_REF
8992 off the base object if possible. indirect_baseN will be true
8993 if baseN is not an address but refers to the object itself. */
8995 if (TREE_CODE (arg0) == ADDR_EXPR)
8997 base0 = get_inner_reference (TREE_OPERAND (arg0, 0),
8998 &bitsize, &bitpos0, &offset0, &mode,
8999 &unsignedp, &volatilep, false);
9000 if (TREE_CODE (base0) == INDIRECT_REF)
9001 base0 = TREE_OPERAND (base0, 0);
9003 indirect_base0 = true;
9005 else if (TREE_CODE (arg0) == POINTER_PLUS_EXPR)
9007 base0 = TREE_OPERAND (arg0, 0);
9008 offset0 = TREE_OPERAND (arg0, 1);
9012 if (TREE_CODE (arg1) == ADDR_EXPR)
9014 base1 = get_inner_reference (TREE_OPERAND (arg1, 0),
9015 &bitsize, &bitpos1, &offset1, &mode,
9016 &unsignedp, &volatilep, false);
9017 if (TREE_CODE (base1) == INDIRECT_REF)
9018 base1 = TREE_OPERAND (base1, 0);
9020 indirect_base1 = true;
9022 else if (TREE_CODE (arg1) == POINTER_PLUS_EXPR)
9024 base1 = TREE_OPERAND (arg1, 0);
9025 offset1 = TREE_OPERAND (arg1, 1);
9028 /* If we have equivalent bases we might be able to simplify. */
9029 if (indirect_base0 == indirect_base1
9030 && operand_equal_p (base0, base1, 0))
9032 /* We can fold this expression to a constant if the non-constant
9033 offset parts are equal. */
9034 if ((offset0 == offset1
9035 || (offset0 && offset1
9036 && operand_equal_p (offset0, offset1, 0)))
9039 || POINTER_TYPE_OVERFLOW_UNDEFINED))
9044 && bitpos0 != bitpos1
9045 && (pointer_may_wrap_p (base0, offset0, bitpos0)
9046 || pointer_may_wrap_p (base1, offset1, bitpos1)))
9047 fold_overflow_warning (("assuming pointer wraparound does not "
9048 "occur when comparing P +- C1 with "
9050 WARN_STRICT_OVERFLOW_CONDITIONAL);
9055 return constant_boolean_node (bitpos0 == bitpos1, type);
9057 return constant_boolean_node (bitpos0 != bitpos1, type);
9059 return constant_boolean_node (bitpos0 < bitpos1, type);
9061 return constant_boolean_node (bitpos0 <= bitpos1, type);
9063 return constant_boolean_node (bitpos0 >= bitpos1, type);
9065 return constant_boolean_node (bitpos0 > bitpos1, type);
9069 /* We can simplify the comparison to a comparison of the variable
9070 offset parts if the constant offset parts are equal.
9071 Be careful to use signed size type here because otherwise we
9072 mess with array offsets in the wrong way. This is possible
9073 because pointer arithmetic is restricted to retain within an
9074 object and overflow on pointer differences is undefined as of
9075 6.5.6/8 and /9 with respect to the signed ptrdiff_t. */
9076 else if (bitpos0 == bitpos1
9077 && ((code == EQ_EXPR || code == NE_EXPR)
9078 || POINTER_TYPE_OVERFLOW_UNDEFINED))
9080 tree signed_size_type_node;
9081 signed_size_type_node = signed_type_for (size_type_node);
9083 /* By converting to signed size type we cover middle-end pointer
9084 arithmetic which operates on unsigned pointer types of size
9085 type size and ARRAY_REF offsets which are properly sign or
9086 zero extended from their type in case it is narrower than
9088 if (offset0 == NULL_TREE)
9089 offset0 = build_int_cst (signed_size_type_node, 0);
9091 offset0 = fold_convert (signed_size_type_node, offset0);
9092 if (offset1 == NULL_TREE)
9093 offset1 = build_int_cst (signed_size_type_node, 0);
9095 offset1 = fold_convert (signed_size_type_node, offset1);
9099 && (pointer_may_wrap_p (base0, offset0, bitpos0)
9100 || pointer_may_wrap_p (base1, offset1, bitpos1)))
9101 fold_overflow_warning (("assuming pointer wraparound does not "
9102 "occur when comparing P +- C1 with "
9104 WARN_STRICT_OVERFLOW_COMPARISON);
9106 return fold_build2 (code, type, offset0, offset1);
9109 /* For non-equal bases we can simplify if they are addresses
9110 of local binding decls or constants. */
9111 else if (indirect_base0 && indirect_base1
9112 /* We know that !operand_equal_p (base0, base1, 0)
9113 because the if condition was false. But make
9114 sure two decls are not the same. */
9116 && TREE_CODE (arg0) == ADDR_EXPR
9117 && TREE_CODE (arg1) == ADDR_EXPR
9118 && (((TREE_CODE (base0) == VAR_DECL
9119 || TREE_CODE (base0) == PARM_DECL)
9120 && (targetm.binds_local_p (base0)
9121 || CONSTANT_CLASS_P (base1)))
9122 || CONSTANT_CLASS_P (base0))
9123 && (((TREE_CODE (base1) == VAR_DECL
9124 || TREE_CODE (base1) == PARM_DECL)
9125 && (targetm.binds_local_p (base1)
9126 || CONSTANT_CLASS_P (base0)))
9127 || CONSTANT_CLASS_P (base1)))
9129 if (code == EQ_EXPR)
9130 return omit_two_operands (type, boolean_false_node, arg0, arg1);
9131 else if (code == NE_EXPR)
9132 return omit_two_operands (type, boolean_true_node, arg0, arg1);
9134 /* For equal offsets we can simplify to a comparison of the
9136 else if (bitpos0 == bitpos1
9138 ? base0 != TREE_OPERAND (arg0, 0) : base0 != arg0)
9140 ? base1 != TREE_OPERAND (arg1, 0) : base1 != arg1)
9141 && ((offset0 == offset1)
9142 || (offset0 && offset1
9143 && operand_equal_p (offset0, offset1, 0))))
9146 base0 = build_fold_addr_expr (base0);
9148 base1 = build_fold_addr_expr (base1);
9149 return fold_build2 (code, type, base0, base1);
9153 /* Transform comparisons of the form X +- C1 CMP Y +- C2 to
9154 X CMP Y +- C2 +- C1 for signed X, Y. This is valid if
9155 the resulting offset is smaller in absolute value than the
9157 if (TYPE_OVERFLOW_UNDEFINED (TREE_TYPE (arg0))
9158 && (TREE_CODE (arg0) == PLUS_EXPR || TREE_CODE (arg0) == MINUS_EXPR)
9159 && (TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST
9160 && !TREE_OVERFLOW (TREE_OPERAND (arg0, 1)))
9161 && (TREE_CODE (arg1) == PLUS_EXPR || TREE_CODE (arg1) == MINUS_EXPR)
9162 && (TREE_CODE (TREE_OPERAND (arg1, 1)) == INTEGER_CST
9163 && !TREE_OVERFLOW (TREE_OPERAND (arg1, 1))))
9165 tree const1 = TREE_OPERAND (arg0, 1);
9166 tree const2 = TREE_OPERAND (arg1, 1);
9167 tree variable1 = TREE_OPERAND (arg0, 0);
9168 tree variable2 = TREE_OPERAND (arg1, 0);
9170 const char * const warnmsg = G_("assuming signed overflow does not "
9171 "occur when combining constants around "
9174 /* Put the constant on the side where it doesn't overflow and is
9175 of lower absolute value than before. */
9176 cst = int_const_binop (TREE_CODE (arg0) == TREE_CODE (arg1)
9177 ? MINUS_EXPR : PLUS_EXPR,
9179 if (!TREE_OVERFLOW (cst)
9180 && tree_int_cst_compare (const2, cst) == tree_int_cst_sgn (const2))
9182 fold_overflow_warning (warnmsg, WARN_STRICT_OVERFLOW_COMPARISON);
9183 return fold_build2 (code, type,
9185 fold_build2 (TREE_CODE (arg1), TREE_TYPE (arg1),
9189 cst = int_const_binop (TREE_CODE (arg0) == TREE_CODE (arg1)
9190 ? MINUS_EXPR : PLUS_EXPR,
9192 if (!TREE_OVERFLOW (cst)
9193 && tree_int_cst_compare (const1, cst) == tree_int_cst_sgn (const1))
9195 fold_overflow_warning (warnmsg, WARN_STRICT_OVERFLOW_COMPARISON);
9196 return fold_build2 (code, type,
9197 fold_build2 (TREE_CODE (arg0), TREE_TYPE (arg0),
9203 /* Transform comparisons of the form X * C1 CMP 0 to X CMP 0 in the
9204 signed arithmetic case. That form is created by the compiler
9205 often enough for folding it to be of value. One example is in
9206 computing loop trip counts after Operator Strength Reduction. */
9207 if (TYPE_OVERFLOW_UNDEFINED (TREE_TYPE (arg0))
9208 && TREE_CODE (arg0) == MULT_EXPR
9209 && (TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST
9210 && !TREE_OVERFLOW (TREE_OPERAND (arg0, 1)))
9211 && integer_zerop (arg1))
9213 tree const1 = TREE_OPERAND (arg0, 1);
9214 tree const2 = arg1; /* zero */
9215 tree variable1 = TREE_OPERAND (arg0, 0);
9216 enum tree_code cmp_code = code;
9218 gcc_assert (!integer_zerop (const1));
9220 fold_overflow_warning (("assuming signed overflow does not occur when "
9221 "eliminating multiplication in comparison "
9223 WARN_STRICT_OVERFLOW_COMPARISON);
9225 /* If const1 is negative we swap the sense of the comparison. */
9226 if (tree_int_cst_sgn (const1) < 0)
9227 cmp_code = swap_tree_comparison (cmp_code);
9229 return fold_build2 (cmp_code, type, variable1, const2);
9232 tem = maybe_canonicalize_comparison (code, type, op0, op1);
9236 if (FLOAT_TYPE_P (TREE_TYPE (arg0)))
9238 tree targ0 = strip_float_extensions (arg0);
9239 tree targ1 = strip_float_extensions (arg1);
9240 tree newtype = TREE_TYPE (targ0);
9242 if (TYPE_PRECISION (TREE_TYPE (targ1)) > TYPE_PRECISION (newtype))
9243 newtype = TREE_TYPE (targ1);
9245 /* Fold (double)float1 CMP (double)float2 into float1 CMP float2. */
9246 if (TYPE_PRECISION (newtype) < TYPE_PRECISION (TREE_TYPE (arg0)))
9247 return fold_build2 (code, type, fold_convert (newtype, targ0),
9248 fold_convert (newtype, targ1));
9250 /* (-a) CMP (-b) -> b CMP a */
9251 if (TREE_CODE (arg0) == NEGATE_EXPR
9252 && TREE_CODE (arg1) == NEGATE_EXPR)
9253 return fold_build2 (code, type, TREE_OPERAND (arg1, 0),
9254 TREE_OPERAND (arg0, 0));
9256 if (TREE_CODE (arg1) == REAL_CST)
9258 REAL_VALUE_TYPE cst;
9259 cst = TREE_REAL_CST (arg1);
9261 /* (-a) CMP CST -> a swap(CMP) (-CST) */
9262 if (TREE_CODE (arg0) == NEGATE_EXPR)
9263 return fold_build2 (swap_tree_comparison (code), type,
9264 TREE_OPERAND (arg0, 0),
9265 build_real (TREE_TYPE (arg1),
9266 REAL_VALUE_NEGATE (cst)));
9268 /* IEEE doesn't distinguish +0 and -0 in comparisons. */
9269 /* a CMP (-0) -> a CMP 0 */
9270 if (REAL_VALUE_MINUS_ZERO (cst))
9271 return fold_build2 (code, type, arg0,
9272 build_real (TREE_TYPE (arg1), dconst0));
9274 /* x != NaN is always true, other ops are always false. */
9275 if (REAL_VALUE_ISNAN (cst)
9276 && ! HONOR_SNANS (TYPE_MODE (TREE_TYPE (arg1))))
9278 tem = (code == NE_EXPR) ? integer_one_node : integer_zero_node;
9279 return omit_one_operand (type, tem, arg0);
9282 /* Fold comparisons against infinity. */
9283 if (REAL_VALUE_ISINF (cst)
9284 && MODE_HAS_INFINITIES (TYPE_MODE (TREE_TYPE (arg1))))
9286 tem = fold_inf_compare (code, type, arg0, arg1);
9287 if (tem != NULL_TREE)
9292 /* If this is a comparison of a real constant with a PLUS_EXPR
9293 or a MINUS_EXPR of a real constant, we can convert it into a
9294 comparison with a revised real constant as long as no overflow
9295 occurs when unsafe_math_optimizations are enabled. */
9296 if (flag_unsafe_math_optimizations
9297 && TREE_CODE (arg1) == REAL_CST
9298 && (TREE_CODE (arg0) == PLUS_EXPR
9299 || TREE_CODE (arg0) == MINUS_EXPR)
9300 && TREE_CODE (TREE_OPERAND (arg0, 1)) == REAL_CST
9301 && 0 != (tem = const_binop (TREE_CODE (arg0) == PLUS_EXPR
9302 ? MINUS_EXPR : PLUS_EXPR,
9303 arg1, TREE_OPERAND (arg0, 1), 0))
9304 && !TREE_OVERFLOW (tem))
9305 return fold_build2 (code, type, TREE_OPERAND (arg0, 0), tem);
9307 /* Likewise, we can simplify a comparison of a real constant with
9308 a MINUS_EXPR whose first operand is also a real constant, i.e.
9309 (c1 - x) < c2 becomes x > c1-c2. Reordering is allowed on
9310 floating-point types only if -fassociative-math is set. */
9311 if (flag_associative_math
9312 && TREE_CODE (arg1) == REAL_CST
9313 && TREE_CODE (arg0) == MINUS_EXPR
9314 && TREE_CODE (TREE_OPERAND (arg0, 0)) == REAL_CST
9315 && 0 != (tem = const_binop (MINUS_EXPR, TREE_OPERAND (arg0, 0),
9317 && !TREE_OVERFLOW (tem))
9318 return fold_build2 (swap_tree_comparison (code), type,
9319 TREE_OPERAND (arg0, 1), tem);
9321 /* Fold comparisons against built-in math functions. */
9322 if (TREE_CODE (arg1) == REAL_CST
9323 && flag_unsafe_math_optimizations
9324 && ! flag_errno_math)
9326 enum built_in_function fcode = builtin_mathfn_code (arg0);
9328 if (fcode != END_BUILTINS)
9330 tem = fold_mathfn_compare (fcode, code, type, arg0, arg1);
9331 if (tem != NULL_TREE)
9337 if (TREE_CODE (TREE_TYPE (arg0)) == INTEGER_TYPE
9338 && CONVERT_EXPR_P (arg0))
9340 /* If we are widening one operand of an integer comparison,
9341 see if the other operand is similarly being widened. Perhaps we
9342 can do the comparison in the narrower type. */
9343 tem = fold_widened_comparison (code, type, arg0, arg1);
9347 /* Or if we are changing signedness. */
9348 tem = fold_sign_changed_comparison (code, type, arg0, arg1);
9353 /* If this is comparing a constant with a MIN_EXPR or a MAX_EXPR of a
9354 constant, we can simplify it. */
9355 if (TREE_CODE (arg1) == INTEGER_CST
9356 && (TREE_CODE (arg0) == MIN_EXPR
9357 || TREE_CODE (arg0) == MAX_EXPR)
9358 && TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST)
9360 tem = optimize_minmax_comparison (code, type, op0, op1);
9365 /* Simplify comparison of something with itself. (For IEEE
9366 floating-point, we can only do some of these simplifications.) */
9367 if (operand_equal_p (arg0, arg1, 0))
9372 if (! FLOAT_TYPE_P (TREE_TYPE (arg0))
9373 || ! HONOR_NANS (TYPE_MODE (TREE_TYPE (arg0))))
9374 return constant_boolean_node (1, type);
9379 if (! FLOAT_TYPE_P (TREE_TYPE (arg0))
9380 || ! HONOR_NANS (TYPE_MODE (TREE_TYPE (arg0))))
9381 return constant_boolean_node (1, type);
9382 return fold_build2 (EQ_EXPR, type, arg0, arg1);
9385 /* For NE, we can only do this simplification if integer
9386 or we don't honor IEEE floating point NaNs. */
9387 if (FLOAT_TYPE_P (TREE_TYPE (arg0))
9388 && HONOR_NANS (TYPE_MODE (TREE_TYPE (arg0))))
9390 /* ... fall through ... */
9393 return constant_boolean_node (0, type);
9399 /* If we are comparing an expression that just has comparisons
9400 of two integer values, arithmetic expressions of those comparisons,
9401 and constants, we can simplify it. There are only three cases
9402 to check: the two values can either be equal, the first can be
9403 greater, or the second can be greater. Fold the expression for
9404 those three values. Since each value must be 0 or 1, we have
9405 eight possibilities, each of which corresponds to the constant 0
9406 or 1 or one of the six possible comparisons.
9408 This handles common cases like (a > b) == 0 but also handles
9409 expressions like ((x > y) - (y > x)) > 0, which supposedly
9410 occur in macroized code. */
9412 if (TREE_CODE (arg1) == INTEGER_CST && TREE_CODE (arg0) != INTEGER_CST)
9414 tree cval1 = 0, cval2 = 0;
9417 if (twoval_comparison_p (arg0, &cval1, &cval2, &save_p)
9418 /* Don't handle degenerate cases here; they should already
9419 have been handled anyway. */
9420 && cval1 != 0 && cval2 != 0
9421 && ! (TREE_CONSTANT (cval1) && TREE_CONSTANT (cval2))
9422 && TREE_TYPE (cval1) == TREE_TYPE (cval2)
9423 && INTEGRAL_TYPE_P (TREE_TYPE (cval1))
9424 && TYPE_MAX_VALUE (TREE_TYPE (cval1))
9425 && TYPE_MAX_VALUE (TREE_TYPE (cval2))
9426 && ! operand_equal_p (TYPE_MIN_VALUE (TREE_TYPE (cval1)),
9427 TYPE_MAX_VALUE (TREE_TYPE (cval2)), 0))
9429 tree maxval = TYPE_MAX_VALUE (TREE_TYPE (cval1));
9430 tree minval = TYPE_MIN_VALUE (TREE_TYPE (cval1));
9432 /* We can't just pass T to eval_subst in case cval1 or cval2
9433 was the same as ARG1. */
9436 = fold_build2 (code, type,
9437 eval_subst (arg0, cval1, maxval,
9441 = fold_build2 (code, type,
9442 eval_subst (arg0, cval1, maxval,
9446 = fold_build2 (code, type,
9447 eval_subst (arg0, cval1, minval,
9451 /* All three of these results should be 0 or 1. Confirm they are.
9452 Then use those values to select the proper code to use. */
9454 if (TREE_CODE (high_result) == INTEGER_CST
9455 && TREE_CODE (equal_result) == INTEGER_CST
9456 && TREE_CODE (low_result) == INTEGER_CST)
9458 /* Make a 3-bit mask with the high-order bit being the
9459 value for `>', the next for '=', and the low for '<'. */
9460 switch ((integer_onep (high_result) * 4)
9461 + (integer_onep (equal_result) * 2)
9462 + integer_onep (low_result))
9466 return omit_one_operand (type, integer_zero_node, arg0);
9487 return omit_one_operand (type, integer_one_node, arg0);
9491 return save_expr (build2 (code, type, cval1, cval2));
9492 return fold_build2 (code, type, cval1, cval2);
9497 /* We can fold X/C1 op C2 where C1 and C2 are integer constants
9498 into a single range test. */
9499 if ((TREE_CODE (arg0) == TRUNC_DIV_EXPR
9500 || TREE_CODE (arg0) == EXACT_DIV_EXPR)
9501 && TREE_CODE (arg1) == INTEGER_CST
9502 && TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST
9503 && !integer_zerop (TREE_OPERAND (arg0, 1))
9504 && !TREE_OVERFLOW (TREE_OPERAND (arg0, 1))
9505 && !TREE_OVERFLOW (arg1))
9507 tem = fold_div_compare (code, type, arg0, arg1);
9508 if (tem != NULL_TREE)
9512 /* Fold ~X op ~Y as Y op X. */
9513 if (TREE_CODE (arg0) == BIT_NOT_EXPR
9514 && TREE_CODE (arg1) == BIT_NOT_EXPR)
9516 tree cmp_type = TREE_TYPE (TREE_OPERAND (arg0, 0));
9517 return fold_build2 (code, type,
9518 fold_convert (cmp_type, TREE_OPERAND (arg1, 0)),
9519 TREE_OPERAND (arg0, 0));
9522 /* Fold ~X op C as X op' ~C, where op' is the swapped comparison. */
9523 if (TREE_CODE (arg0) == BIT_NOT_EXPR
9524 && TREE_CODE (arg1) == INTEGER_CST)
9526 tree cmp_type = TREE_TYPE (TREE_OPERAND (arg0, 0));
9527 return fold_build2 (swap_tree_comparison (code), type,
9528 TREE_OPERAND (arg0, 0),
9529 fold_build1 (BIT_NOT_EXPR, cmp_type,
9530 fold_convert (cmp_type, arg1)));
9537 /* Subroutine of fold_binary. Optimize complex multiplications of the
9538 form z * conj(z), as pow(realpart(z),2) + pow(imagpart(z),2). The
9539 argument EXPR represents the expression "z" of type TYPE. */
9542 fold_mult_zconjz (tree type, tree expr)
9544 tree itype = TREE_TYPE (type);
9545 tree rpart, ipart, tem;
9547 if (TREE_CODE (expr) == COMPLEX_EXPR)
9549 rpart = TREE_OPERAND (expr, 0);
9550 ipart = TREE_OPERAND (expr, 1);
9552 else if (TREE_CODE (expr) == COMPLEX_CST)
9554 rpart = TREE_REALPART (expr);
9555 ipart = TREE_IMAGPART (expr);
9559 expr = save_expr (expr);
9560 rpart = fold_build1 (REALPART_EXPR, itype, expr);
9561 ipart = fold_build1 (IMAGPART_EXPR, itype, expr);
9564 rpart = save_expr (rpart);
9565 ipart = save_expr (ipart);
9566 tem = fold_build2 (PLUS_EXPR, itype,
9567 fold_build2 (MULT_EXPR, itype, rpart, rpart),
9568 fold_build2 (MULT_EXPR, itype, ipart, ipart));
9569 return fold_build2 (COMPLEX_EXPR, type, tem,
9570 fold_convert (itype, integer_zero_node));
9574 /* Subroutine of fold_binary. If P is the value of EXPR, computes
9575 power-of-two M and (arbitrary) N such that M divides (P-N). This condition
9576 guarantees that P and N have the same least significant log2(M) bits.
9577 N is not otherwise constrained. In particular, N is not normalized to
9578 0 <= N < M as is common. In general, the precise value of P is unknown.
9579 M is chosen as large as possible such that constant N can be determined.
9581 Returns M and sets *RESIDUE to N.
9583 If ALLOW_FUNC_ALIGN is true, do take functions' DECL_ALIGN_UNIT into
9584 account. This is not always possible due to PR 35705.
9587 static unsigned HOST_WIDE_INT
9588 get_pointer_modulus_and_residue (tree expr, unsigned HOST_WIDE_INT *residue,
9589 bool allow_func_align)
9591 enum tree_code code;
9595 code = TREE_CODE (expr);
9596 if (code == ADDR_EXPR)
9598 expr = TREE_OPERAND (expr, 0);
9599 if (handled_component_p (expr))
9601 HOST_WIDE_INT bitsize, bitpos;
9603 enum machine_mode mode;
9604 int unsignedp, volatilep;
9606 expr = get_inner_reference (expr, &bitsize, &bitpos, &offset,
9607 &mode, &unsignedp, &volatilep, false);
9608 *residue = bitpos / BITS_PER_UNIT;
9611 if (TREE_CODE (offset) == INTEGER_CST)
9612 *residue += TREE_INT_CST_LOW (offset);
9614 /* We don't handle more complicated offset expressions. */
9620 && (allow_func_align || TREE_CODE (expr) != FUNCTION_DECL))
9621 return DECL_ALIGN_UNIT (expr);
9623 else if (code == POINTER_PLUS_EXPR)
9626 unsigned HOST_WIDE_INT modulus;
9627 enum tree_code inner_code;
9629 op0 = TREE_OPERAND (expr, 0);
9631 modulus = get_pointer_modulus_and_residue (op0, residue,
9634 op1 = TREE_OPERAND (expr, 1);
9636 inner_code = TREE_CODE (op1);
9637 if (inner_code == INTEGER_CST)
9639 *residue += TREE_INT_CST_LOW (op1);
9642 else if (inner_code == MULT_EXPR)
9644 op1 = TREE_OPERAND (op1, 1);
9645 if (TREE_CODE (op1) == INTEGER_CST)
9647 unsigned HOST_WIDE_INT align;
9649 /* Compute the greatest power-of-2 divisor of op1. */
9650 align = TREE_INT_CST_LOW (op1);
9653 /* If align is non-zero and less than *modulus, replace
9654 *modulus with align., If align is 0, then either op1 is 0
9655 or the greatest power-of-2 divisor of op1 doesn't fit in an
9656 unsigned HOST_WIDE_INT. In either case, no additional
9657 constraint is imposed. */
9659 modulus = MIN (modulus, align);
9666 /* If we get here, we were unable to determine anything useful about the
9672 /* Fold a binary expression of code CODE and type TYPE with operands
9673 OP0 and OP1. Return the folded expression if folding is
9674 successful. Otherwise, return NULL_TREE. */
9677 fold_binary (enum tree_code code, tree type, tree op0, tree op1)
9679 enum tree_code_class kind = TREE_CODE_CLASS (code);
9680 tree arg0, arg1, tem;
9681 tree t1 = NULL_TREE;
9682 bool strict_overflow_p;
9684 gcc_assert (IS_EXPR_CODE_CLASS (kind)
9685 && TREE_CODE_LENGTH (code) == 2
9687 && op1 != NULL_TREE);
9692 /* Strip any conversions that don't change the mode. This is
9693 safe for every expression, except for a comparison expression
9694 because its signedness is derived from its operands. So, in
9695 the latter case, only strip conversions that don't change the
9696 signedness. MIN_EXPR/MAX_EXPR also need signedness of arguments
9699 Note that this is done as an internal manipulation within the
9700 constant folder, in order to find the simplest representation
9701 of the arguments so that their form can be studied. In any
9702 cases, the appropriate type conversions should be put back in
9703 the tree that will get out of the constant folder. */
9705 if (kind == tcc_comparison || code == MIN_EXPR || code == MAX_EXPR)
9707 STRIP_SIGN_NOPS (arg0);
9708 STRIP_SIGN_NOPS (arg1);
9716 /* Note that TREE_CONSTANT isn't enough: static var addresses are
9717 constant but we can't do arithmetic on them. */
9718 if ((TREE_CODE (arg0) == INTEGER_CST && TREE_CODE (arg1) == INTEGER_CST)
9719 || (TREE_CODE (arg0) == REAL_CST && TREE_CODE (arg1) == REAL_CST)
9720 || (TREE_CODE (arg0) == FIXED_CST && TREE_CODE (arg1) == FIXED_CST)
9721 || (TREE_CODE (arg0) == FIXED_CST && TREE_CODE (arg1) == INTEGER_CST)
9722 || (TREE_CODE (arg0) == COMPLEX_CST && TREE_CODE (arg1) == COMPLEX_CST)
9723 || (TREE_CODE (arg0) == VECTOR_CST && TREE_CODE (arg1) == VECTOR_CST))
9725 if (kind == tcc_binary)
9727 /* Make sure type and arg0 have the same saturating flag. */
9728 gcc_assert (TYPE_SATURATING (type)
9729 == TYPE_SATURATING (TREE_TYPE (arg0)));
9730 tem = const_binop (code, arg0, arg1, 0);
9732 else if (kind == tcc_comparison)
9733 tem = fold_relational_const (code, type, arg0, arg1);
9737 if (tem != NULL_TREE)
9739 if (TREE_TYPE (tem) != type)
9740 tem = fold_convert (type, tem);
9745 /* If this is a commutative operation, and ARG0 is a constant, move it
9746 to ARG1 to reduce the number of tests below. */
9747 if (commutative_tree_code (code)
9748 && tree_swap_operands_p (arg0, arg1, true))
9749 return fold_build2 (code, type, op1, op0);
9751 /* ARG0 is the first operand of EXPR, and ARG1 is the second operand.
9753 First check for cases where an arithmetic operation is applied to a
9754 compound, conditional, or comparison operation. Push the arithmetic
9755 operation inside the compound or conditional to see if any folding
9756 can then be done. Convert comparison to conditional for this purpose.
9757 The also optimizes non-constant cases that used to be done in
9760 Before we do that, see if this is a BIT_AND_EXPR or a BIT_IOR_EXPR,
9761 one of the operands is a comparison and the other is a comparison, a
9762 BIT_AND_EXPR with the constant 1, or a truth value. In that case, the
9763 code below would make the expression more complex. Change it to a
9764 TRUTH_{AND,OR}_EXPR. Likewise, convert a similar NE_EXPR to
9765 TRUTH_XOR_EXPR and an EQ_EXPR to the inversion of a TRUTH_XOR_EXPR. */
9767 if ((code == BIT_AND_EXPR || code == BIT_IOR_EXPR
9768 || code == EQ_EXPR || code == NE_EXPR)
9769 && ((truth_value_p (TREE_CODE (arg0))
9770 && (truth_value_p (TREE_CODE (arg1))
9771 || (TREE_CODE (arg1) == BIT_AND_EXPR
9772 && integer_onep (TREE_OPERAND (arg1, 1)))))
9773 || (truth_value_p (TREE_CODE (arg1))
9774 && (truth_value_p (TREE_CODE (arg0))
9775 || (TREE_CODE (arg0) == BIT_AND_EXPR
9776 && integer_onep (TREE_OPERAND (arg0, 1)))))))
9778 tem = fold_build2 (code == BIT_AND_EXPR ? TRUTH_AND_EXPR
9779 : code == BIT_IOR_EXPR ? TRUTH_OR_EXPR
9782 fold_convert (boolean_type_node, arg0),
9783 fold_convert (boolean_type_node, arg1));
9785 if (code == EQ_EXPR)
9786 tem = invert_truthvalue (tem);
9788 return fold_convert (type, tem);
9791 if (TREE_CODE_CLASS (code) == tcc_binary
9792 || TREE_CODE_CLASS (code) == tcc_comparison)
9794 if (TREE_CODE (arg0) == COMPOUND_EXPR)
9795 return build2 (COMPOUND_EXPR, type, TREE_OPERAND (arg0, 0),
9796 fold_build2 (code, type,
9797 fold_convert (TREE_TYPE (op0),
9798 TREE_OPERAND (arg0, 1)),
9800 if (TREE_CODE (arg1) == COMPOUND_EXPR
9801 && reorder_operands_p (arg0, TREE_OPERAND (arg1, 0)))
9802 return build2 (COMPOUND_EXPR, type, TREE_OPERAND (arg1, 0),
9803 fold_build2 (code, type, op0,
9804 fold_convert (TREE_TYPE (op1),
9805 TREE_OPERAND (arg1, 1))));
9807 if (TREE_CODE (arg0) == COND_EXPR || COMPARISON_CLASS_P (arg0))
9809 tem = fold_binary_op_with_conditional_arg (code, type, op0, op1,
9811 /*cond_first_p=*/1);
9812 if (tem != NULL_TREE)
9816 if (TREE_CODE (arg1) == COND_EXPR || COMPARISON_CLASS_P (arg1))
9818 tem = fold_binary_op_with_conditional_arg (code, type, op0, op1,
9820 /*cond_first_p=*/0);
9821 if (tem != NULL_TREE)
9828 case POINTER_PLUS_EXPR:
9829 /* 0 +p index -> (type)index */
9830 if (integer_zerop (arg0))
9831 return non_lvalue (fold_convert (type, arg1));
9833 /* PTR +p 0 -> PTR */
9834 if (integer_zerop (arg1))
9835 return non_lvalue (fold_convert (type, arg0));
9837 /* INT +p INT -> (PTR)(INT + INT). Stripping types allows for this. */
9838 if (INTEGRAL_TYPE_P (TREE_TYPE (arg1))
9839 && INTEGRAL_TYPE_P (TREE_TYPE (arg0)))
9840 return fold_convert (type, fold_build2 (PLUS_EXPR, sizetype,
9841 fold_convert (sizetype, arg1),
9842 fold_convert (sizetype, arg0)));
9844 /* index +p PTR -> PTR +p index */
9845 if (POINTER_TYPE_P (TREE_TYPE (arg1))
9846 && INTEGRAL_TYPE_P (TREE_TYPE (arg0)))
9847 return fold_build2 (POINTER_PLUS_EXPR, type,
9848 fold_convert (type, arg1),
9849 fold_convert (sizetype, arg0));
9851 /* (PTR +p B) +p A -> PTR +p (B + A) */
9852 if (TREE_CODE (arg0) == POINTER_PLUS_EXPR)
9855 tree arg01 = fold_convert (sizetype, TREE_OPERAND (arg0, 1));
9856 tree arg00 = TREE_OPERAND (arg0, 0);
9857 inner = fold_build2 (PLUS_EXPR, sizetype,
9858 arg01, fold_convert (sizetype, arg1));
9859 return fold_convert (type,
9860 fold_build2 (POINTER_PLUS_EXPR,
9861 TREE_TYPE (arg00), arg00, inner));
9864 /* PTR_CST +p CST -> CST1 */
9865 if (TREE_CODE (arg0) == INTEGER_CST && TREE_CODE (arg1) == INTEGER_CST)
9866 return fold_build2 (PLUS_EXPR, type, arg0, fold_convert (type, arg1));
9868 /* Try replacing &a[i1] +p c * i2 with &a[i1 + i2], if c is step
9869 of the array. Loop optimizer sometimes produce this type of
9871 if (TREE_CODE (arg0) == ADDR_EXPR)
9873 tem = try_move_mult_to_index (arg0, fold_convert (sizetype, arg1));
9875 return fold_convert (type, tem);
9881 /* A + (-B) -> A - B */
9882 if (TREE_CODE (arg1) == NEGATE_EXPR)
9883 return fold_build2 (MINUS_EXPR, type,
9884 fold_convert (type, arg0),
9885 fold_convert (type, TREE_OPERAND (arg1, 0)));
9886 /* (-A) + B -> B - A */
9887 if (TREE_CODE (arg0) == NEGATE_EXPR
9888 && reorder_operands_p (TREE_OPERAND (arg0, 0), arg1))
9889 return fold_build2 (MINUS_EXPR, type,
9890 fold_convert (type, arg1),
9891 fold_convert (type, TREE_OPERAND (arg0, 0)));
9893 if (INTEGRAL_TYPE_P (type))
9895 /* Convert ~A + 1 to -A. */
9896 if (TREE_CODE (arg0) == BIT_NOT_EXPR
9897 && integer_onep (arg1))
9898 return fold_build1 (NEGATE_EXPR, type,
9899 fold_convert (type, TREE_OPERAND (arg0, 0)));
9902 if (TREE_CODE (arg0) == BIT_NOT_EXPR
9903 && !TYPE_OVERFLOW_TRAPS (type))
9905 tree tem = TREE_OPERAND (arg0, 0);
9908 if (operand_equal_p (tem, arg1, 0))
9910 t1 = build_int_cst_type (type, -1);
9911 return omit_one_operand (type, t1, arg1);
9916 if (TREE_CODE (arg1) == BIT_NOT_EXPR
9917 && !TYPE_OVERFLOW_TRAPS (type))
9919 tree tem = TREE_OPERAND (arg1, 0);
9922 if (operand_equal_p (arg0, tem, 0))
9924 t1 = build_int_cst_type (type, -1);
9925 return omit_one_operand (type, t1, arg0);
9929 /* X + (X / CST) * -CST is X % CST. */
9930 if (TREE_CODE (arg1) == MULT_EXPR
9931 && TREE_CODE (TREE_OPERAND (arg1, 0)) == TRUNC_DIV_EXPR
9932 && operand_equal_p (arg0,
9933 TREE_OPERAND (TREE_OPERAND (arg1, 0), 0), 0))
9935 tree cst0 = TREE_OPERAND (TREE_OPERAND (arg1, 0), 1);
9936 tree cst1 = TREE_OPERAND (arg1, 1);
9937 tree sum = fold_binary (PLUS_EXPR, TREE_TYPE (cst1), cst1, cst0);
9938 if (sum && integer_zerop (sum))
9939 return fold_convert (type,
9940 fold_build2 (TRUNC_MOD_EXPR,
9941 TREE_TYPE (arg0), arg0, cst0));
9945 /* Handle (A1 * C1) + (A2 * C2) with A1, A2 or C1, C2 being the
9946 same or one. Make sure type is not saturating.
9947 fold_plusminus_mult_expr will re-associate. */
9948 if ((TREE_CODE (arg0) == MULT_EXPR
9949 || TREE_CODE (arg1) == MULT_EXPR)
9950 && !TYPE_SATURATING (type)
9951 && (!FLOAT_TYPE_P (type) || flag_associative_math))
9953 tree tem = fold_plusminus_mult_expr (code, type, arg0, arg1);
9958 if (! FLOAT_TYPE_P (type))
9960 if (integer_zerop (arg1))
9961 return non_lvalue (fold_convert (type, arg0));
9963 /* If we are adding two BIT_AND_EXPR's, both of which are and'ing
9964 with a constant, and the two constants have no bits in common,
9965 we should treat this as a BIT_IOR_EXPR since this may produce more
9967 if (TREE_CODE (arg0) == BIT_AND_EXPR
9968 && TREE_CODE (arg1) == BIT_AND_EXPR
9969 && TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST
9970 && TREE_CODE (TREE_OPERAND (arg1, 1)) == INTEGER_CST
9971 && integer_zerop (const_binop (BIT_AND_EXPR,
9972 TREE_OPERAND (arg0, 1),
9973 TREE_OPERAND (arg1, 1), 0)))
9975 code = BIT_IOR_EXPR;
9979 /* Reassociate (plus (plus (mult) (foo)) (mult)) as
9980 (plus (plus (mult) (mult)) (foo)) so that we can
9981 take advantage of the factoring cases below. */
9982 if (((TREE_CODE (arg0) == PLUS_EXPR
9983 || TREE_CODE (arg0) == MINUS_EXPR)
9984 && TREE_CODE (arg1) == MULT_EXPR)
9985 || ((TREE_CODE (arg1) == PLUS_EXPR
9986 || TREE_CODE (arg1) == MINUS_EXPR)
9987 && TREE_CODE (arg0) == MULT_EXPR))
9989 tree parg0, parg1, parg, marg;
9990 enum tree_code pcode;
9992 if (TREE_CODE (arg1) == MULT_EXPR)
9993 parg = arg0, marg = arg1;
9995 parg = arg1, marg = arg0;
9996 pcode = TREE_CODE (parg);
9997 parg0 = TREE_OPERAND (parg, 0);
9998 parg1 = TREE_OPERAND (parg, 1);
10000 STRIP_NOPS (parg1);
10002 if (TREE_CODE (parg0) == MULT_EXPR
10003 && TREE_CODE (parg1) != MULT_EXPR)
10004 return fold_build2 (pcode, type,
10005 fold_build2 (PLUS_EXPR, type,
10006 fold_convert (type, parg0),
10007 fold_convert (type, marg)),
10008 fold_convert (type, parg1));
10009 if (TREE_CODE (parg0) != MULT_EXPR
10010 && TREE_CODE (parg1) == MULT_EXPR)
10011 return fold_build2 (PLUS_EXPR, type,
10012 fold_convert (type, parg0),
10013 fold_build2 (pcode, type,
10014 fold_convert (type, marg),
10015 fold_convert (type,
10021 /* See if ARG1 is zero and X + ARG1 reduces to X. */
10022 if (fold_real_zero_addition_p (TREE_TYPE (arg0), arg1, 0))
10023 return non_lvalue (fold_convert (type, arg0));
10025 /* Likewise if the operands are reversed. */
10026 if (fold_real_zero_addition_p (TREE_TYPE (arg1), arg0, 0))
10027 return non_lvalue (fold_convert (type, arg1));
10029 /* Convert X + -C into X - C. */
10030 if (TREE_CODE (arg1) == REAL_CST
10031 && REAL_VALUE_NEGATIVE (TREE_REAL_CST (arg1)))
10033 tem = fold_negate_const (arg1, type);
10034 if (!TREE_OVERFLOW (arg1) || !flag_trapping_math)
10035 return fold_build2 (MINUS_EXPR, type,
10036 fold_convert (type, arg0),
10037 fold_convert (type, tem));
10040 /* Fold __complex__ ( x, 0 ) + __complex__ ( 0, y )
10041 to __complex__ ( x, y ). This is not the same for SNaNs or
10042 if signed zeros are involved. */
10043 if (!HONOR_SNANS (TYPE_MODE (TREE_TYPE (arg0)))
10044 && !HONOR_SIGNED_ZEROS (TYPE_MODE (TREE_TYPE (arg0)))
10045 && COMPLEX_FLOAT_TYPE_P (TREE_TYPE (arg0)))
10047 tree rtype = TREE_TYPE (TREE_TYPE (arg0));
10048 tree arg0r = fold_unary (REALPART_EXPR, rtype, arg0);
10049 tree arg0i = fold_unary (IMAGPART_EXPR, rtype, arg0);
10050 bool arg0rz = false, arg0iz = false;
10051 if ((arg0r && (arg0rz = real_zerop (arg0r)))
10052 || (arg0i && (arg0iz = real_zerop (arg0i))))
10054 tree arg1r = fold_unary (REALPART_EXPR, rtype, arg1);
10055 tree arg1i = fold_unary (IMAGPART_EXPR, rtype, arg1);
10056 if (arg0rz && arg1i && real_zerop (arg1i))
10058 tree rp = arg1r ? arg1r
10059 : build1 (REALPART_EXPR, rtype, arg1);
10060 tree ip = arg0i ? arg0i
10061 : build1 (IMAGPART_EXPR, rtype, arg0);
10062 return fold_build2 (COMPLEX_EXPR, type, rp, ip);
10064 else if (arg0iz && arg1r && real_zerop (arg1r))
10066 tree rp = arg0r ? arg0r
10067 : build1 (REALPART_EXPR, rtype, arg0);
10068 tree ip = arg1i ? arg1i
10069 : build1 (IMAGPART_EXPR, rtype, arg1);
10070 return fold_build2 (COMPLEX_EXPR, type, rp, ip);
10075 if (flag_unsafe_math_optimizations
10076 && (TREE_CODE (arg0) == RDIV_EXPR || TREE_CODE (arg0) == MULT_EXPR)
10077 && (TREE_CODE (arg1) == RDIV_EXPR || TREE_CODE (arg1) == MULT_EXPR)
10078 && (tem = distribute_real_division (code, type, arg0, arg1)))
10081 /* Convert x+x into x*2.0. */
10082 if (operand_equal_p (arg0, arg1, 0)
10083 && SCALAR_FLOAT_TYPE_P (type))
10084 return fold_build2 (MULT_EXPR, type, arg0,
10085 build_real (type, dconst2));
10087 /* Convert a + (b*c + d*e) into (a + b*c) + d*e.
10088 We associate floats only if the user has specified
10089 -fassociative-math. */
10090 if (flag_associative_math
10091 && TREE_CODE (arg1) == PLUS_EXPR
10092 && TREE_CODE (arg0) != MULT_EXPR)
10094 tree tree10 = TREE_OPERAND (arg1, 0);
10095 tree tree11 = TREE_OPERAND (arg1, 1);
10096 if (TREE_CODE (tree11) == MULT_EXPR
10097 && TREE_CODE (tree10) == MULT_EXPR)
10100 tree0 = fold_build2 (PLUS_EXPR, type, arg0, tree10);
10101 return fold_build2 (PLUS_EXPR, type, tree0, tree11);
10104 /* Convert (b*c + d*e) + a into b*c + (d*e +a).
10105 We associate floats only if the user has specified
10106 -fassociative-math. */
10107 if (flag_associative_math
10108 && TREE_CODE (arg0) == PLUS_EXPR
10109 && TREE_CODE (arg1) != MULT_EXPR)
10111 tree tree00 = TREE_OPERAND (arg0, 0);
10112 tree tree01 = TREE_OPERAND (arg0, 1);
10113 if (TREE_CODE (tree01) == MULT_EXPR
10114 && TREE_CODE (tree00) == MULT_EXPR)
10117 tree0 = fold_build2 (PLUS_EXPR, type, tree01, arg1);
10118 return fold_build2 (PLUS_EXPR, type, tree00, tree0);
10124 /* (A << C1) + (A >> C2) if A is unsigned and C1+C2 is the size of A
10125 is a rotate of A by C1 bits. */
10126 /* (A << B) + (A >> (Z - B)) if A is unsigned and Z is the size of A
10127 is a rotate of A by B bits. */
10129 enum tree_code code0, code1;
10131 code0 = TREE_CODE (arg0);
10132 code1 = TREE_CODE (arg1);
10133 if (((code0 == RSHIFT_EXPR && code1 == LSHIFT_EXPR)
10134 || (code1 == RSHIFT_EXPR && code0 == LSHIFT_EXPR))
10135 && operand_equal_p (TREE_OPERAND (arg0, 0),
10136 TREE_OPERAND (arg1, 0), 0)
10137 && (rtype = TREE_TYPE (TREE_OPERAND (arg0, 0)),
10138 TYPE_UNSIGNED (rtype))
10139 /* Only create rotates in complete modes. Other cases are not
10140 expanded properly. */
10141 && TYPE_PRECISION (rtype) == GET_MODE_PRECISION (TYPE_MODE (rtype)))
10143 tree tree01, tree11;
10144 enum tree_code code01, code11;
10146 tree01 = TREE_OPERAND (arg0, 1);
10147 tree11 = TREE_OPERAND (arg1, 1);
10148 STRIP_NOPS (tree01);
10149 STRIP_NOPS (tree11);
10150 code01 = TREE_CODE (tree01);
10151 code11 = TREE_CODE (tree11);
10152 if (code01 == INTEGER_CST
10153 && code11 == INTEGER_CST
10154 && TREE_INT_CST_HIGH (tree01) == 0
10155 && TREE_INT_CST_HIGH (tree11) == 0
10156 && ((TREE_INT_CST_LOW (tree01) + TREE_INT_CST_LOW (tree11))
10157 == TYPE_PRECISION (TREE_TYPE (TREE_OPERAND (arg0, 0)))))
10158 return build2 (LROTATE_EXPR, type, TREE_OPERAND (arg0, 0),
10159 code0 == LSHIFT_EXPR ? tree01 : tree11);
10160 else if (code11 == MINUS_EXPR)
10162 tree tree110, tree111;
10163 tree110 = TREE_OPERAND (tree11, 0);
10164 tree111 = TREE_OPERAND (tree11, 1);
10165 STRIP_NOPS (tree110);
10166 STRIP_NOPS (tree111);
10167 if (TREE_CODE (tree110) == INTEGER_CST
10168 && 0 == compare_tree_int (tree110,
10170 (TREE_TYPE (TREE_OPERAND
10172 && operand_equal_p (tree01, tree111, 0))
10173 return build2 ((code0 == LSHIFT_EXPR
10176 type, TREE_OPERAND (arg0, 0), tree01);
10178 else if (code01 == MINUS_EXPR)
10180 tree tree010, tree011;
10181 tree010 = TREE_OPERAND (tree01, 0);
10182 tree011 = TREE_OPERAND (tree01, 1);
10183 STRIP_NOPS (tree010);
10184 STRIP_NOPS (tree011);
10185 if (TREE_CODE (tree010) == INTEGER_CST
10186 && 0 == compare_tree_int (tree010,
10188 (TREE_TYPE (TREE_OPERAND
10190 && operand_equal_p (tree11, tree011, 0))
10191 return build2 ((code0 != LSHIFT_EXPR
10194 type, TREE_OPERAND (arg0, 0), tree11);
10200 /* In most languages, can't associate operations on floats through
10201 parentheses. Rather than remember where the parentheses were, we
10202 don't associate floats at all, unless the user has specified
10203 -fassociative-math.
10204 And, we need to make sure type is not saturating. */
10206 if ((! FLOAT_TYPE_P (type) || flag_associative_math)
10207 && !TYPE_SATURATING (type))
10209 tree var0, con0, lit0, minus_lit0;
10210 tree var1, con1, lit1, minus_lit1;
10213 /* Split both trees into variables, constants, and literals. Then
10214 associate each group together, the constants with literals,
10215 then the result with variables. This increases the chances of
10216 literals being recombined later and of generating relocatable
10217 expressions for the sum of a constant and literal. */
10218 var0 = split_tree (arg0, code, &con0, &lit0, &minus_lit0, 0);
10219 var1 = split_tree (arg1, code, &con1, &lit1, &minus_lit1,
10220 code == MINUS_EXPR);
10222 /* With undefined overflow we can only associate constants
10223 with one variable. */
10224 if (((POINTER_TYPE_P (type) && POINTER_TYPE_OVERFLOW_UNDEFINED)
10225 || (INTEGRAL_TYPE_P (type) && !TYPE_OVERFLOW_WRAPS (type)))
10231 if (TREE_CODE (tmp0) == NEGATE_EXPR)
10232 tmp0 = TREE_OPERAND (tmp0, 0);
10233 if (TREE_CODE (tmp1) == NEGATE_EXPR)
10234 tmp1 = TREE_OPERAND (tmp1, 0);
10235 /* The only case we can still associate with two variables
10236 is if they are the same, modulo negation. */
10237 if (!operand_equal_p (tmp0, tmp1, 0))
10241 /* Only do something if we found more than two objects. Otherwise,
10242 nothing has changed and we risk infinite recursion. */
10244 && (2 < ((var0 != 0) + (var1 != 0)
10245 + (con0 != 0) + (con1 != 0)
10246 + (lit0 != 0) + (lit1 != 0)
10247 + (minus_lit0 != 0) + (minus_lit1 != 0))))
10249 /* Recombine MINUS_EXPR operands by using PLUS_EXPR. */
10250 if (code == MINUS_EXPR)
10253 var0 = associate_trees (var0, var1, code, type);
10254 con0 = associate_trees (con0, con1, code, type);
10255 lit0 = associate_trees (lit0, lit1, code, type);
10256 minus_lit0 = associate_trees (minus_lit0, minus_lit1, code, type);
10258 /* Preserve the MINUS_EXPR if the negative part of the literal is
10259 greater than the positive part. Otherwise, the multiplicative
10260 folding code (i.e extract_muldiv) may be fooled in case
10261 unsigned constants are subtracted, like in the following
10262 example: ((X*2 + 4) - 8U)/2. */
10263 if (minus_lit0 && lit0)
10265 if (TREE_CODE (lit0) == INTEGER_CST
10266 && TREE_CODE (minus_lit0) == INTEGER_CST
10267 && tree_int_cst_lt (lit0, minus_lit0))
10269 minus_lit0 = associate_trees (minus_lit0, lit0,
10275 lit0 = associate_trees (lit0, minus_lit0,
10283 return fold_convert (type,
10284 associate_trees (var0, minus_lit0,
10285 MINUS_EXPR, type));
10288 con0 = associate_trees (con0, minus_lit0,
10290 return fold_convert (type,
10291 associate_trees (var0, con0,
10296 con0 = associate_trees (con0, lit0, code, type);
10297 return fold_convert (type, associate_trees (var0, con0,
10305 /* Pointer simplifications for subtraction, simple reassociations. */
10306 if (POINTER_TYPE_P (TREE_TYPE (arg1)) && POINTER_TYPE_P (TREE_TYPE (arg0)))
10308 /* (PTR0 p+ A) - (PTR1 p+ B) -> (PTR0 - PTR1) + (A - B) */
10309 if (TREE_CODE (arg0) == POINTER_PLUS_EXPR
10310 && TREE_CODE (arg1) == POINTER_PLUS_EXPR)
10312 tree arg00 = fold_convert (type, TREE_OPERAND (arg0, 0));
10313 tree arg01 = fold_convert (type, TREE_OPERAND (arg0, 1));
10314 tree arg10 = fold_convert (type, TREE_OPERAND (arg1, 0));
10315 tree arg11 = fold_convert (type, TREE_OPERAND (arg1, 1));
10316 return fold_build2 (PLUS_EXPR, type,
10317 fold_build2 (MINUS_EXPR, type, arg00, arg10),
10318 fold_build2 (MINUS_EXPR, type, arg01, arg11));
10320 /* (PTR0 p+ A) - PTR1 -> (PTR0 - PTR1) + A, assuming PTR0 - PTR1 simplifies. */
10321 else if (TREE_CODE (arg0) == POINTER_PLUS_EXPR)
10323 tree arg00 = fold_convert (type, TREE_OPERAND (arg0, 0));
10324 tree arg01 = fold_convert (type, TREE_OPERAND (arg0, 1));
10325 tree tmp = fold_binary (MINUS_EXPR, type, arg00, fold_convert (type, arg1));
10327 return fold_build2 (PLUS_EXPR, type, tmp, arg01);
10330 /* A - (-B) -> A + B */
10331 if (TREE_CODE (arg1) == NEGATE_EXPR)
10332 return fold_build2 (PLUS_EXPR, type, op0,
10333 fold_convert (type, TREE_OPERAND (arg1, 0)));
10334 /* (-A) - B -> (-B) - A where B is easily negated and we can swap. */
10335 if (TREE_CODE (arg0) == NEGATE_EXPR
10336 && (FLOAT_TYPE_P (type)
10337 || INTEGRAL_TYPE_P (type))
10338 && negate_expr_p (arg1)
10339 && reorder_operands_p (arg0, arg1))
10340 return fold_build2 (MINUS_EXPR, type,
10341 fold_convert (type, negate_expr (arg1)),
10342 fold_convert (type, TREE_OPERAND (arg0, 0)));
10343 /* Convert -A - 1 to ~A. */
10344 if (INTEGRAL_TYPE_P (type)
10345 && TREE_CODE (arg0) == NEGATE_EXPR
10346 && integer_onep (arg1)
10347 && !TYPE_OVERFLOW_TRAPS (type))
10348 return fold_build1 (BIT_NOT_EXPR, type,
10349 fold_convert (type, TREE_OPERAND (arg0, 0)));
10351 /* Convert -1 - A to ~A. */
10352 if (INTEGRAL_TYPE_P (type)
10353 && integer_all_onesp (arg0))
10354 return fold_build1 (BIT_NOT_EXPR, type, op1);
10357 /* X - (X / CST) * CST is X % CST. */
10358 if (INTEGRAL_TYPE_P (type)
10359 && TREE_CODE (arg1) == MULT_EXPR
10360 && TREE_CODE (TREE_OPERAND (arg1, 0)) == TRUNC_DIV_EXPR
10361 && operand_equal_p (arg0,
10362 TREE_OPERAND (TREE_OPERAND (arg1, 0), 0), 0)
10363 && operand_equal_p (TREE_OPERAND (TREE_OPERAND (arg1, 0), 1),
10364 TREE_OPERAND (arg1, 1), 0))
10365 return fold_convert (type,
10366 fold_build2 (TRUNC_MOD_EXPR, TREE_TYPE (arg0),
10367 arg0, TREE_OPERAND (arg1, 1)));
10369 if (! FLOAT_TYPE_P (type))
10371 if (integer_zerop (arg0))
10372 return negate_expr (fold_convert (type, arg1));
10373 if (integer_zerop (arg1))
10374 return non_lvalue (fold_convert (type, arg0));
10376 /* Fold A - (A & B) into ~B & A. */
10377 if (!TREE_SIDE_EFFECTS (arg0)
10378 && TREE_CODE (arg1) == BIT_AND_EXPR)
10380 if (operand_equal_p (arg0, TREE_OPERAND (arg1, 1), 0))
10382 tree arg10 = fold_convert (type, TREE_OPERAND (arg1, 0));
10383 return fold_build2 (BIT_AND_EXPR, type,
10384 fold_build1 (BIT_NOT_EXPR, type, arg10),
10385 fold_convert (type, arg0));
10387 if (operand_equal_p (arg0, TREE_OPERAND (arg1, 0), 0))
10389 tree arg11 = fold_convert (type, TREE_OPERAND (arg1, 1));
10390 return fold_build2 (BIT_AND_EXPR, type,
10391 fold_build1 (BIT_NOT_EXPR, type, arg11),
10392 fold_convert (type, arg0));
10396 /* Fold (A & ~B) - (A & B) into (A ^ B) - B, where B is
10397 any power of 2 minus 1. */
10398 if (TREE_CODE (arg0) == BIT_AND_EXPR
10399 && TREE_CODE (arg1) == BIT_AND_EXPR
10400 && operand_equal_p (TREE_OPERAND (arg0, 0),
10401 TREE_OPERAND (arg1, 0), 0))
10403 tree mask0 = TREE_OPERAND (arg0, 1);
10404 tree mask1 = TREE_OPERAND (arg1, 1);
10405 tree tem = fold_build1 (BIT_NOT_EXPR, type, mask0);
10407 if (operand_equal_p (tem, mask1, 0))
10409 tem = fold_build2 (BIT_XOR_EXPR, type,
10410 TREE_OPERAND (arg0, 0), mask1);
10411 return fold_build2 (MINUS_EXPR, type, tem, mask1);
10416 /* See if ARG1 is zero and X - ARG1 reduces to X. */
10417 else if (fold_real_zero_addition_p (TREE_TYPE (arg0), arg1, 1))
10418 return non_lvalue (fold_convert (type, arg0));
10420 /* (ARG0 - ARG1) is the same as (-ARG1 + ARG0). So check whether
10421 ARG0 is zero and X + ARG0 reduces to X, since that would mean
10422 (-ARG1 + ARG0) reduces to -ARG1. */
10423 else if (fold_real_zero_addition_p (TREE_TYPE (arg1), arg0, 0))
10424 return negate_expr (fold_convert (type, arg1));
10426 /* Fold __complex__ ( x, 0 ) - __complex__ ( 0, y ) to
10427 __complex__ ( x, -y ). This is not the same for SNaNs or if
10428 signed zeros are involved. */
10429 if (!HONOR_SNANS (TYPE_MODE (TREE_TYPE (arg0)))
10430 && !HONOR_SIGNED_ZEROS (TYPE_MODE (TREE_TYPE (arg0)))
10431 && COMPLEX_FLOAT_TYPE_P (TREE_TYPE (arg0)))
10433 tree rtype = TREE_TYPE (TREE_TYPE (arg0));
10434 tree arg0r = fold_unary (REALPART_EXPR, rtype, arg0);
10435 tree arg0i = fold_unary (IMAGPART_EXPR, rtype, arg0);
10436 bool arg0rz = false, arg0iz = false;
10437 if ((arg0r && (arg0rz = real_zerop (arg0r)))
10438 || (arg0i && (arg0iz = real_zerop (arg0i))))
10440 tree arg1r = fold_unary (REALPART_EXPR, rtype, arg1);
10441 tree arg1i = fold_unary (IMAGPART_EXPR, rtype, arg1);
10442 if (arg0rz && arg1i && real_zerop (arg1i))
10444 tree rp = fold_build1 (NEGATE_EXPR, rtype,
10446 : build1 (REALPART_EXPR, rtype, arg1));
10447 tree ip = arg0i ? arg0i
10448 : build1 (IMAGPART_EXPR, rtype, arg0);
10449 return fold_build2 (COMPLEX_EXPR, type, rp, ip);
10451 else if (arg0iz && arg1r && real_zerop (arg1r))
10453 tree rp = arg0r ? arg0r
10454 : build1 (REALPART_EXPR, rtype, arg0);
10455 tree ip = fold_build1 (NEGATE_EXPR, rtype,
10457 : build1 (IMAGPART_EXPR, rtype, arg1));
10458 return fold_build2 (COMPLEX_EXPR, type, rp, ip);
10463 /* Fold &x - &x. This can happen from &x.foo - &x.
10464 This is unsafe for certain floats even in non-IEEE formats.
10465 In IEEE, it is unsafe because it does wrong for NaNs.
10466 Also note that operand_equal_p is always false if an operand
10469 if ((!FLOAT_TYPE_P (type) || !HONOR_NANS (TYPE_MODE (type)))
10470 && operand_equal_p (arg0, arg1, 0))
10471 return fold_convert (type, integer_zero_node);
10473 /* A - B -> A + (-B) if B is easily negatable. */
10474 if (negate_expr_p (arg1)
10475 && ((FLOAT_TYPE_P (type)
10476 /* Avoid this transformation if B is a positive REAL_CST. */
10477 && (TREE_CODE (arg1) != REAL_CST
10478 || REAL_VALUE_NEGATIVE (TREE_REAL_CST (arg1))))
10479 || INTEGRAL_TYPE_P (type)))
10480 return fold_build2 (PLUS_EXPR, type,
10481 fold_convert (type, arg0),
10482 fold_convert (type, negate_expr (arg1)));
10484 /* Try folding difference of addresses. */
10486 HOST_WIDE_INT diff;
10488 if ((TREE_CODE (arg0) == ADDR_EXPR
10489 || TREE_CODE (arg1) == ADDR_EXPR)
10490 && ptr_difference_const (arg0, arg1, &diff))
10491 return build_int_cst_type (type, diff);
10494 /* Fold &a[i] - &a[j] to i-j. */
10495 if (TREE_CODE (arg0) == ADDR_EXPR
10496 && TREE_CODE (TREE_OPERAND (arg0, 0)) == ARRAY_REF
10497 && TREE_CODE (arg1) == ADDR_EXPR
10498 && TREE_CODE (TREE_OPERAND (arg1, 0)) == ARRAY_REF)
10500 tree aref0 = TREE_OPERAND (arg0, 0);
10501 tree aref1 = TREE_OPERAND (arg1, 0);
10502 if (operand_equal_p (TREE_OPERAND (aref0, 0),
10503 TREE_OPERAND (aref1, 0), 0))
10505 tree op0 = fold_convert (type, TREE_OPERAND (aref0, 1));
10506 tree op1 = fold_convert (type, TREE_OPERAND (aref1, 1));
10507 tree esz = array_ref_element_size (aref0);
10508 tree diff = build2 (MINUS_EXPR, type, op0, op1);
10509 return fold_build2 (MULT_EXPR, type, diff,
10510 fold_convert (type, esz));
10515 if (flag_unsafe_math_optimizations
10516 && (TREE_CODE (arg0) == RDIV_EXPR || TREE_CODE (arg0) == MULT_EXPR)
10517 && (TREE_CODE (arg1) == RDIV_EXPR || TREE_CODE (arg1) == MULT_EXPR)
10518 && (tem = distribute_real_division (code, type, arg0, arg1)))
10521 /* Handle (A1 * C1) - (A2 * C2) with A1, A2 or C1, C2 being the
10522 same or one. Make sure type is not saturating.
10523 fold_plusminus_mult_expr will re-associate. */
10524 if ((TREE_CODE (arg0) == MULT_EXPR
10525 || TREE_CODE (arg1) == MULT_EXPR)
10526 && !TYPE_SATURATING (type)
10527 && (!FLOAT_TYPE_P (type) || flag_associative_math))
10529 tree tem = fold_plusminus_mult_expr (code, type, arg0, arg1);
10537 /* (-A) * (-B) -> A * B */
10538 if (TREE_CODE (arg0) == NEGATE_EXPR && negate_expr_p (arg1))
10539 return fold_build2 (MULT_EXPR, type,
10540 fold_convert (type, TREE_OPERAND (arg0, 0)),
10541 fold_convert (type, negate_expr (arg1)));
10542 if (TREE_CODE (arg1) == NEGATE_EXPR && negate_expr_p (arg0))
10543 return fold_build2 (MULT_EXPR, type,
10544 fold_convert (type, negate_expr (arg0)),
10545 fold_convert (type, TREE_OPERAND (arg1, 0)));
10547 if (! FLOAT_TYPE_P (type))
10549 if (integer_zerop (arg1))
10550 return omit_one_operand (type, arg1, arg0);
10551 if (integer_onep (arg1))
10552 return non_lvalue (fold_convert (type, arg0));
10553 /* Transform x * -1 into -x. Make sure to do the negation
10554 on the original operand with conversions not stripped
10555 because we can only strip non-sign-changing conversions. */
10556 if (integer_all_onesp (arg1))
10557 return fold_convert (type, negate_expr (op0));
10558 /* Transform x * -C into -x * C if x is easily negatable. */
10559 if (TREE_CODE (arg1) == INTEGER_CST
10560 && tree_int_cst_sgn (arg1) == -1
10561 && negate_expr_p (arg0)
10562 && (tem = negate_expr (arg1)) != arg1
10563 && !TREE_OVERFLOW (tem))
10564 return fold_build2 (MULT_EXPR, type,
10565 fold_convert (type, negate_expr (arg0)), tem);
10567 /* (a * (1 << b)) is (a << b) */
10568 if (TREE_CODE (arg1) == LSHIFT_EXPR
10569 && integer_onep (TREE_OPERAND (arg1, 0)))
10570 return fold_build2 (LSHIFT_EXPR, type, op0,
10571 TREE_OPERAND (arg1, 1));
10572 if (TREE_CODE (arg0) == LSHIFT_EXPR
10573 && integer_onep (TREE_OPERAND (arg0, 0)))
10574 return fold_build2 (LSHIFT_EXPR, type, op1,
10575 TREE_OPERAND (arg0, 1));
10577 /* (A + A) * C -> A * 2 * C */
10578 if (TREE_CODE (arg0) == PLUS_EXPR
10579 && TREE_CODE (arg1) == INTEGER_CST
10580 && operand_equal_p (TREE_OPERAND (arg0, 0),
10581 TREE_OPERAND (arg0, 1), 0))
10582 return fold_build2 (MULT_EXPR, type,
10583 omit_one_operand (type, TREE_OPERAND (arg0, 0),
10584 TREE_OPERAND (arg0, 1)),
10585 fold_build2 (MULT_EXPR, type,
10586 build_int_cst (type, 2) , arg1));
10588 strict_overflow_p = false;
10589 if (TREE_CODE (arg1) == INTEGER_CST
10590 && 0 != (tem = extract_muldiv (op0, arg1, code, NULL_TREE,
10591 &strict_overflow_p)))
10593 if (strict_overflow_p)
10594 fold_overflow_warning (("assuming signed overflow does not "
10595 "occur when simplifying "
10597 WARN_STRICT_OVERFLOW_MISC);
10598 return fold_convert (type, tem);
10601 /* Optimize z * conj(z) for integer complex numbers. */
10602 if (TREE_CODE (arg0) == CONJ_EXPR
10603 && operand_equal_p (TREE_OPERAND (arg0, 0), arg1, 0))
10604 return fold_mult_zconjz (type, arg1);
10605 if (TREE_CODE (arg1) == CONJ_EXPR
10606 && operand_equal_p (arg0, TREE_OPERAND (arg1, 0), 0))
10607 return fold_mult_zconjz (type, arg0);
10611 /* Maybe fold x * 0 to 0. The expressions aren't the same
10612 when x is NaN, since x * 0 is also NaN. Nor are they the
10613 same in modes with signed zeros, since multiplying a
10614 negative value by 0 gives -0, not +0. */
10615 if (!HONOR_NANS (TYPE_MODE (TREE_TYPE (arg0)))
10616 && !HONOR_SIGNED_ZEROS (TYPE_MODE (TREE_TYPE (arg0)))
10617 && real_zerop (arg1))
10618 return omit_one_operand (type, arg1, arg0);
10619 /* In IEEE floating point, x*1 is not equivalent to x for snans. */
10620 if (!HONOR_SNANS (TYPE_MODE (TREE_TYPE (arg0)))
10621 && real_onep (arg1))
10622 return non_lvalue (fold_convert (type, arg0));
10624 /* Transform x * -1.0 into -x. */
10625 if (!HONOR_SNANS (TYPE_MODE (TREE_TYPE (arg0)))
10626 && real_minus_onep (arg1))
10627 return fold_convert (type, negate_expr (arg0));
10629 /* Convert (C1/X)*C2 into (C1*C2)/X. This transformation may change
10630 the result for floating point types due to rounding so it is applied
10631 only if -fassociative-math was specify. */
10632 if (flag_associative_math
10633 && TREE_CODE (arg0) == RDIV_EXPR
10634 && TREE_CODE (arg1) == REAL_CST
10635 && TREE_CODE (TREE_OPERAND (arg0, 0)) == REAL_CST)
10637 tree tem = const_binop (MULT_EXPR, TREE_OPERAND (arg0, 0),
10640 return fold_build2 (RDIV_EXPR, type, tem,
10641 TREE_OPERAND (arg0, 1));
10644 /* Strip sign operations from X in X*X, i.e. -Y*-Y -> Y*Y. */
10645 if (operand_equal_p (arg0, arg1, 0))
10647 tree tem = fold_strip_sign_ops (arg0);
10648 if (tem != NULL_TREE)
10650 tem = fold_convert (type, tem);
10651 return fold_build2 (MULT_EXPR, type, tem, tem);
10655 /* Fold z * +-I to __complex__ (-+__imag z, +-__real z).
10656 This is not the same for NaNs or if signed zeros are
10658 if (!HONOR_NANS (TYPE_MODE (TREE_TYPE (arg0)))
10659 && !HONOR_SIGNED_ZEROS (TYPE_MODE (TREE_TYPE (arg0)))
10660 && COMPLEX_FLOAT_TYPE_P (TREE_TYPE (arg0))
10661 && TREE_CODE (arg1) == COMPLEX_CST
10662 && real_zerop (TREE_REALPART (arg1)))
10664 tree rtype = TREE_TYPE (TREE_TYPE (arg0));
10665 if (real_onep (TREE_IMAGPART (arg1)))
10666 return fold_build2 (COMPLEX_EXPR, type,
10667 negate_expr (fold_build1 (IMAGPART_EXPR,
10669 fold_build1 (REALPART_EXPR, rtype, arg0));
10670 else if (real_minus_onep (TREE_IMAGPART (arg1)))
10671 return fold_build2 (COMPLEX_EXPR, type,
10672 fold_build1 (IMAGPART_EXPR, rtype, arg0),
10673 negate_expr (fold_build1 (REALPART_EXPR,
10677 /* Optimize z * conj(z) for floating point complex numbers.
10678 Guarded by flag_unsafe_math_optimizations as non-finite
10679 imaginary components don't produce scalar results. */
10680 if (flag_unsafe_math_optimizations
10681 && TREE_CODE (arg0) == CONJ_EXPR
10682 && operand_equal_p (TREE_OPERAND (arg0, 0), arg1, 0))
10683 return fold_mult_zconjz (type, arg1);
10684 if (flag_unsafe_math_optimizations
10685 && TREE_CODE (arg1) == CONJ_EXPR
10686 && operand_equal_p (arg0, TREE_OPERAND (arg1, 0), 0))
10687 return fold_mult_zconjz (type, arg0);
10689 if (flag_unsafe_math_optimizations)
10691 enum built_in_function fcode0 = builtin_mathfn_code (arg0);
10692 enum built_in_function fcode1 = builtin_mathfn_code (arg1);
10694 /* Optimizations of root(...)*root(...). */
10695 if (fcode0 == fcode1 && BUILTIN_ROOT_P (fcode0))
10698 tree arg00 = CALL_EXPR_ARG (arg0, 0);
10699 tree arg10 = CALL_EXPR_ARG (arg1, 0);
10701 /* Optimize sqrt(x)*sqrt(x) as x. */
10702 if (BUILTIN_SQRT_P (fcode0)
10703 && operand_equal_p (arg00, arg10, 0)
10704 && ! HONOR_SNANS (TYPE_MODE (type)))
10707 /* Optimize root(x)*root(y) as root(x*y). */
10708 rootfn = TREE_OPERAND (CALL_EXPR_FN (arg0), 0);
10709 arg = fold_build2 (MULT_EXPR, type, arg00, arg10);
10710 return build_call_expr (rootfn, 1, arg);
10713 /* Optimize expN(x)*expN(y) as expN(x+y). */
10714 if (fcode0 == fcode1 && BUILTIN_EXPONENT_P (fcode0))
10716 tree expfn = TREE_OPERAND (CALL_EXPR_FN (arg0), 0);
10717 tree arg = fold_build2 (PLUS_EXPR, type,
10718 CALL_EXPR_ARG (arg0, 0),
10719 CALL_EXPR_ARG (arg1, 0));
10720 return build_call_expr (expfn, 1, arg);
10723 /* Optimizations of pow(...)*pow(...). */
10724 if ((fcode0 == BUILT_IN_POW && fcode1 == BUILT_IN_POW)
10725 || (fcode0 == BUILT_IN_POWF && fcode1 == BUILT_IN_POWF)
10726 || (fcode0 == BUILT_IN_POWL && fcode1 == BUILT_IN_POWL))
10728 tree arg00 = CALL_EXPR_ARG (arg0, 0);
10729 tree arg01 = CALL_EXPR_ARG (arg0, 1);
10730 tree arg10 = CALL_EXPR_ARG (arg1, 0);
10731 tree arg11 = CALL_EXPR_ARG (arg1, 1);
10733 /* Optimize pow(x,y)*pow(z,y) as pow(x*z,y). */
10734 if (operand_equal_p (arg01, arg11, 0))
10736 tree powfn = TREE_OPERAND (CALL_EXPR_FN (arg0), 0);
10737 tree arg = fold_build2 (MULT_EXPR, type, arg00, arg10);
10738 return build_call_expr (powfn, 2, arg, arg01);
10741 /* Optimize pow(x,y)*pow(x,z) as pow(x,y+z). */
10742 if (operand_equal_p (arg00, arg10, 0))
10744 tree powfn = TREE_OPERAND (CALL_EXPR_FN (arg0), 0);
10745 tree arg = fold_build2 (PLUS_EXPR, type, arg01, arg11);
10746 return build_call_expr (powfn, 2, arg00, arg);
10750 /* Optimize tan(x)*cos(x) as sin(x). */
10751 if (((fcode0 == BUILT_IN_TAN && fcode1 == BUILT_IN_COS)
10752 || (fcode0 == BUILT_IN_TANF && fcode1 == BUILT_IN_COSF)
10753 || (fcode0 == BUILT_IN_TANL && fcode1 == BUILT_IN_COSL)
10754 || (fcode0 == BUILT_IN_COS && fcode1 == BUILT_IN_TAN)
10755 || (fcode0 == BUILT_IN_COSF && fcode1 == BUILT_IN_TANF)
10756 || (fcode0 == BUILT_IN_COSL && fcode1 == BUILT_IN_TANL))
10757 && operand_equal_p (CALL_EXPR_ARG (arg0, 0),
10758 CALL_EXPR_ARG (arg1, 0), 0))
10760 tree sinfn = mathfn_built_in (type, BUILT_IN_SIN);
10762 if (sinfn != NULL_TREE)
10763 return build_call_expr (sinfn, 1, CALL_EXPR_ARG (arg0, 0));
10766 /* Optimize x*pow(x,c) as pow(x,c+1). */
10767 if (fcode1 == BUILT_IN_POW
10768 || fcode1 == BUILT_IN_POWF
10769 || fcode1 == BUILT_IN_POWL)
10771 tree arg10 = CALL_EXPR_ARG (arg1, 0);
10772 tree arg11 = CALL_EXPR_ARG (arg1, 1);
10773 if (TREE_CODE (arg11) == REAL_CST
10774 && !TREE_OVERFLOW (arg11)
10775 && operand_equal_p (arg0, arg10, 0))
10777 tree powfn = TREE_OPERAND (CALL_EXPR_FN (arg1), 0);
10781 c = TREE_REAL_CST (arg11);
10782 real_arithmetic (&c, PLUS_EXPR, &c, &dconst1);
10783 arg = build_real (type, c);
10784 return build_call_expr (powfn, 2, arg0, arg);
10788 /* Optimize pow(x,c)*x as pow(x,c+1). */
10789 if (fcode0 == BUILT_IN_POW
10790 || fcode0 == BUILT_IN_POWF
10791 || fcode0 == BUILT_IN_POWL)
10793 tree arg00 = CALL_EXPR_ARG (arg0, 0);
10794 tree arg01 = CALL_EXPR_ARG (arg0, 1);
10795 if (TREE_CODE (arg01) == REAL_CST
10796 && !TREE_OVERFLOW (arg01)
10797 && operand_equal_p (arg1, arg00, 0))
10799 tree powfn = TREE_OPERAND (CALL_EXPR_FN (arg0), 0);
10803 c = TREE_REAL_CST (arg01);
10804 real_arithmetic (&c, PLUS_EXPR, &c, &dconst1);
10805 arg = build_real (type, c);
10806 return build_call_expr (powfn, 2, arg1, arg);
10810 /* Optimize x*x as pow(x,2.0), which is expanded as x*x. */
10811 if (optimize_function_for_speed_p (cfun)
10812 && operand_equal_p (arg0, arg1, 0))
10814 tree powfn = mathfn_built_in (type, BUILT_IN_POW);
10818 tree arg = build_real (type, dconst2);
10819 return build_call_expr (powfn, 2, arg0, arg);
10828 if (integer_all_onesp (arg1))
10829 return omit_one_operand (type, arg1, arg0);
10830 if (integer_zerop (arg1))
10831 return non_lvalue (fold_convert (type, arg0));
10832 if (operand_equal_p (arg0, arg1, 0))
10833 return non_lvalue (fold_convert (type, arg0));
10835 /* ~X | X is -1. */
10836 if (TREE_CODE (arg0) == BIT_NOT_EXPR
10837 && operand_equal_p (TREE_OPERAND (arg0, 0), arg1, 0))
10839 t1 = fold_convert (type, integer_zero_node);
10840 t1 = fold_unary (BIT_NOT_EXPR, type, t1);
10841 return omit_one_operand (type, t1, arg1);
10844 /* X | ~X is -1. */
10845 if (TREE_CODE (arg1) == BIT_NOT_EXPR
10846 && operand_equal_p (arg0, TREE_OPERAND (arg1, 0), 0))
10848 t1 = fold_convert (type, integer_zero_node);
10849 t1 = fold_unary (BIT_NOT_EXPR, type, t1);
10850 return omit_one_operand (type, t1, arg0);
10853 /* Canonicalize (X & C1) | C2. */
10854 if (TREE_CODE (arg0) == BIT_AND_EXPR
10855 && TREE_CODE (arg1) == INTEGER_CST
10856 && TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST)
10858 unsigned HOST_WIDE_INT hi1, lo1, hi2, lo2, hi3, lo3, mlo, mhi;
10859 int width = TYPE_PRECISION (type), w;
10860 hi1 = TREE_INT_CST_HIGH (TREE_OPERAND (arg0, 1));
10861 lo1 = TREE_INT_CST_LOW (TREE_OPERAND (arg0, 1));
10862 hi2 = TREE_INT_CST_HIGH (arg1);
10863 lo2 = TREE_INT_CST_LOW (arg1);
10865 /* If (C1&C2) == C1, then (X&C1)|C2 becomes (X,C2). */
10866 if ((hi1 & hi2) == hi1 && (lo1 & lo2) == lo1)
10867 return omit_one_operand (type, arg1, TREE_OPERAND (arg0, 0));
10869 if (width > HOST_BITS_PER_WIDE_INT)
10871 mhi = (unsigned HOST_WIDE_INT) -1
10872 >> (2 * HOST_BITS_PER_WIDE_INT - width);
10878 mlo = (unsigned HOST_WIDE_INT) -1
10879 >> (HOST_BITS_PER_WIDE_INT - width);
10882 /* If (C1|C2) == ~0 then (X&C1)|C2 becomes X|C2. */
10883 if ((~(hi1 | hi2) & mhi) == 0 && (~(lo1 | lo2) & mlo) == 0)
10884 return fold_build2 (BIT_IOR_EXPR, type,
10885 TREE_OPERAND (arg0, 0), arg1);
10887 /* Minimize the number of bits set in C1, i.e. C1 := C1 & ~C2,
10888 unless (C1 & ~C2) | (C2 & C3) for some C3 is a mask of some
10889 mode which allows further optimizations. */
10896 for (w = BITS_PER_UNIT;
10897 w <= width && w <= HOST_BITS_PER_WIDE_INT;
10900 unsigned HOST_WIDE_INT mask
10901 = (unsigned HOST_WIDE_INT) -1 >> (HOST_BITS_PER_WIDE_INT - w);
10902 if (((lo1 | lo2) & mask) == mask
10903 && (lo1 & ~mask) == 0 && hi1 == 0)
10910 if (hi3 != hi1 || lo3 != lo1)
10911 return fold_build2 (BIT_IOR_EXPR, type,
10912 fold_build2 (BIT_AND_EXPR, type,
10913 TREE_OPERAND (arg0, 0),
10914 build_int_cst_wide (type,
10919 /* (X & Y) | Y is (X, Y). */
10920 if (TREE_CODE (arg0) == BIT_AND_EXPR
10921 && operand_equal_p (TREE_OPERAND (arg0, 1), arg1, 0))
10922 return omit_one_operand (type, arg1, TREE_OPERAND (arg0, 0));
10923 /* (X & Y) | X is (Y, X). */
10924 if (TREE_CODE (arg0) == BIT_AND_EXPR
10925 && operand_equal_p (TREE_OPERAND (arg0, 0), arg1, 0)
10926 && reorder_operands_p (TREE_OPERAND (arg0, 1), arg1))
10927 return omit_one_operand (type, arg1, TREE_OPERAND (arg0, 1));
10928 /* X | (X & Y) is (Y, X). */
10929 if (TREE_CODE (arg1) == BIT_AND_EXPR
10930 && operand_equal_p (arg0, TREE_OPERAND (arg1, 0), 0)
10931 && reorder_operands_p (arg0, TREE_OPERAND (arg1, 1)))
10932 return omit_one_operand (type, arg0, TREE_OPERAND (arg1, 1));
10933 /* X | (Y & X) is (Y, X). */
10934 if (TREE_CODE (arg1) == BIT_AND_EXPR
10935 && operand_equal_p (arg0, TREE_OPERAND (arg1, 1), 0)
10936 && reorder_operands_p (arg0, TREE_OPERAND (arg1, 0)))
10937 return omit_one_operand (type, arg0, TREE_OPERAND (arg1, 0));
10939 t1 = distribute_bit_expr (code, type, arg0, arg1);
10940 if (t1 != NULL_TREE)
10943 /* Convert (or (not arg0) (not arg1)) to (not (and (arg0) (arg1))).
10945 This results in more efficient code for machines without a NAND
10946 instruction. Combine will canonicalize to the first form
10947 which will allow use of NAND instructions provided by the
10948 backend if they exist. */
10949 if (TREE_CODE (arg0) == BIT_NOT_EXPR
10950 && TREE_CODE (arg1) == BIT_NOT_EXPR)
10952 return fold_build1 (BIT_NOT_EXPR, type,
10953 build2 (BIT_AND_EXPR, type,
10954 fold_convert (type,
10955 TREE_OPERAND (arg0, 0)),
10956 fold_convert (type,
10957 TREE_OPERAND (arg1, 0))));
10960 /* See if this can be simplified into a rotate first. If that
10961 is unsuccessful continue in the association code. */
10965 if (integer_zerop (arg1))
10966 return non_lvalue (fold_convert (type, arg0));
10967 if (integer_all_onesp (arg1))
10968 return fold_build1 (BIT_NOT_EXPR, type, op0);
10969 if (operand_equal_p (arg0, arg1, 0))
10970 return omit_one_operand (type, integer_zero_node, arg0);
10972 /* ~X ^ X is -1. */
10973 if (TREE_CODE (arg0) == BIT_NOT_EXPR
10974 && operand_equal_p (TREE_OPERAND (arg0, 0), arg1, 0))
10976 t1 = fold_convert (type, integer_zero_node);
10977 t1 = fold_unary (BIT_NOT_EXPR, type, t1);
10978 return omit_one_operand (type, t1, arg1);
10981 /* X ^ ~X is -1. */
10982 if (TREE_CODE (arg1) == BIT_NOT_EXPR
10983 && operand_equal_p (arg0, TREE_OPERAND (arg1, 0), 0))
10985 t1 = fold_convert (type, integer_zero_node);
10986 t1 = fold_unary (BIT_NOT_EXPR, type, t1);
10987 return omit_one_operand (type, t1, arg0);
10990 /* If we are XORing two BIT_AND_EXPR's, both of which are and'ing
10991 with a constant, and the two constants have no bits in common,
10992 we should treat this as a BIT_IOR_EXPR since this may produce more
10993 simplifications. */
10994 if (TREE_CODE (arg0) == BIT_AND_EXPR
10995 && TREE_CODE (arg1) == BIT_AND_EXPR
10996 && TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST
10997 && TREE_CODE (TREE_OPERAND (arg1, 1)) == INTEGER_CST
10998 && integer_zerop (const_binop (BIT_AND_EXPR,
10999 TREE_OPERAND (arg0, 1),
11000 TREE_OPERAND (arg1, 1), 0)))
11002 code = BIT_IOR_EXPR;
11006 /* (X | Y) ^ X -> Y & ~ X*/
11007 if (TREE_CODE (arg0) == BIT_IOR_EXPR
11008 && operand_equal_p (TREE_OPERAND (arg0, 0), arg1, 0))
11010 tree t2 = TREE_OPERAND (arg0, 1);
11011 t1 = fold_build1 (BIT_NOT_EXPR, TREE_TYPE (arg1),
11013 t1 = fold_build2 (BIT_AND_EXPR, type, fold_convert (type, t2),
11014 fold_convert (type, t1));
11018 /* (Y | X) ^ X -> Y & ~ X*/
11019 if (TREE_CODE (arg0) == BIT_IOR_EXPR
11020 && operand_equal_p (TREE_OPERAND (arg0, 1), arg1, 0))
11022 tree t2 = TREE_OPERAND (arg0, 0);
11023 t1 = fold_build1 (BIT_NOT_EXPR, TREE_TYPE (arg1),
11025 t1 = fold_build2 (BIT_AND_EXPR, type, fold_convert (type, t2),
11026 fold_convert (type, t1));
11030 /* X ^ (X | Y) -> Y & ~ X*/
11031 if (TREE_CODE (arg1) == BIT_IOR_EXPR
11032 && operand_equal_p (TREE_OPERAND (arg1, 0), arg0, 0))
11034 tree t2 = TREE_OPERAND (arg1, 1);
11035 t1 = fold_build1 (BIT_NOT_EXPR, TREE_TYPE (arg0),
11037 t1 = fold_build2 (BIT_AND_EXPR, type, fold_convert (type, t2),
11038 fold_convert (type, t1));
11042 /* X ^ (Y | X) -> Y & ~ X*/
11043 if (TREE_CODE (arg1) == BIT_IOR_EXPR
11044 && operand_equal_p (TREE_OPERAND (arg1, 1), arg0, 0))
11046 tree t2 = TREE_OPERAND (arg1, 0);
11047 t1 = fold_build1 (BIT_NOT_EXPR, TREE_TYPE (arg0),
11049 t1 = fold_build2 (BIT_AND_EXPR, type, fold_convert (type, t2),
11050 fold_convert (type, t1));
11054 /* Convert ~X ^ ~Y to X ^ Y. */
11055 if (TREE_CODE (arg0) == BIT_NOT_EXPR
11056 && TREE_CODE (arg1) == BIT_NOT_EXPR)
11057 return fold_build2 (code, type,
11058 fold_convert (type, TREE_OPERAND (arg0, 0)),
11059 fold_convert (type, TREE_OPERAND (arg1, 0)));
11061 /* Convert ~X ^ C to X ^ ~C. */
11062 if (TREE_CODE (arg0) == BIT_NOT_EXPR
11063 && TREE_CODE (arg1) == INTEGER_CST)
11064 return fold_build2 (code, type,
11065 fold_convert (type, TREE_OPERAND (arg0, 0)),
11066 fold_build1 (BIT_NOT_EXPR, type, arg1));
11068 /* Fold (X & 1) ^ 1 as (X & 1) == 0. */
11069 if (TREE_CODE (arg0) == BIT_AND_EXPR
11070 && integer_onep (TREE_OPERAND (arg0, 1))
11071 && integer_onep (arg1))
11072 return fold_build2 (EQ_EXPR, type, arg0,
11073 build_int_cst (TREE_TYPE (arg0), 0));
11075 /* Fold (X & Y) ^ Y as ~X & Y. */
11076 if (TREE_CODE (arg0) == BIT_AND_EXPR
11077 && operand_equal_p (TREE_OPERAND (arg0, 1), arg1, 0))
11079 tem = fold_convert (type, TREE_OPERAND (arg0, 0));
11080 return fold_build2 (BIT_AND_EXPR, type,
11081 fold_build1 (BIT_NOT_EXPR, type, tem),
11082 fold_convert (type, arg1));
11084 /* Fold (X & Y) ^ X as ~Y & X. */
11085 if (TREE_CODE (arg0) == BIT_AND_EXPR
11086 && operand_equal_p (TREE_OPERAND (arg0, 0), arg1, 0)
11087 && reorder_operands_p (TREE_OPERAND (arg0, 1), arg1))
11089 tem = fold_convert (type, TREE_OPERAND (arg0, 1));
11090 return fold_build2 (BIT_AND_EXPR, type,
11091 fold_build1 (BIT_NOT_EXPR, type, tem),
11092 fold_convert (type, arg1));
11094 /* Fold X ^ (X & Y) as X & ~Y. */
11095 if (TREE_CODE (arg1) == BIT_AND_EXPR
11096 && operand_equal_p (arg0, TREE_OPERAND (arg1, 0), 0))
11098 tem = fold_convert (type, TREE_OPERAND (arg1, 1));
11099 return fold_build2 (BIT_AND_EXPR, type,
11100 fold_convert (type, arg0),
11101 fold_build1 (BIT_NOT_EXPR, type, tem));
11103 /* Fold X ^ (Y & X) as ~Y & X. */
11104 if (TREE_CODE (arg1) == BIT_AND_EXPR
11105 && operand_equal_p (arg0, TREE_OPERAND (arg1, 1), 0)
11106 && reorder_operands_p (arg0, TREE_OPERAND (arg1, 0)))
11108 tem = fold_convert (type, TREE_OPERAND (arg1, 0));
11109 return fold_build2 (BIT_AND_EXPR, type,
11110 fold_build1 (BIT_NOT_EXPR, type, tem),
11111 fold_convert (type, arg0));
11114 /* See if this can be simplified into a rotate first. If that
11115 is unsuccessful continue in the association code. */
11119 if (integer_all_onesp (arg1))
11120 return non_lvalue (fold_convert (type, arg0));
11121 if (integer_zerop (arg1))
11122 return omit_one_operand (type, arg1, arg0);
11123 if (operand_equal_p (arg0, arg1, 0))
11124 return non_lvalue (fold_convert (type, arg0));
11126 /* ~X & X is always zero. */
11127 if (TREE_CODE (arg0) == BIT_NOT_EXPR
11128 && operand_equal_p (TREE_OPERAND (arg0, 0), arg1, 0))
11129 return omit_one_operand (type, integer_zero_node, arg1);
11131 /* X & ~X is always zero. */
11132 if (TREE_CODE (arg1) == BIT_NOT_EXPR
11133 && operand_equal_p (arg0, TREE_OPERAND (arg1, 0), 0))
11134 return omit_one_operand (type, integer_zero_node, arg0);
11136 /* Canonicalize (X | C1) & C2 as (X & C2) | (C1 & C2). */
11137 if (TREE_CODE (arg0) == BIT_IOR_EXPR
11138 && TREE_CODE (arg1) == INTEGER_CST
11139 && TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST)
11141 tree tmp1 = fold_convert (type, arg1);
11142 tree tmp2 = fold_convert (type, TREE_OPERAND (arg0, 0));
11143 tree tmp3 = fold_convert (type, TREE_OPERAND (arg0, 1));
11144 tmp2 = fold_build2 (BIT_AND_EXPR, type, tmp2, tmp1);
11145 tmp3 = fold_build2 (BIT_AND_EXPR, type, tmp3, tmp1);
11146 return fold_convert (type,
11147 fold_build2 (BIT_IOR_EXPR, type, tmp2, tmp3));
11150 /* (X | Y) & Y is (X, Y). */
11151 if (TREE_CODE (arg0) == BIT_IOR_EXPR
11152 && operand_equal_p (TREE_OPERAND (arg0, 1), arg1, 0))
11153 return omit_one_operand (type, arg1, TREE_OPERAND (arg0, 0));
11154 /* (X | Y) & X is (Y, X). */
11155 if (TREE_CODE (arg0) == BIT_IOR_EXPR
11156 && operand_equal_p (TREE_OPERAND (arg0, 0), arg1, 0)
11157 && reorder_operands_p (TREE_OPERAND (arg0, 1), arg1))
11158 return omit_one_operand (type, arg1, TREE_OPERAND (arg0, 1));
11159 /* X & (X | Y) is (Y, X). */
11160 if (TREE_CODE (arg1) == BIT_IOR_EXPR
11161 && operand_equal_p (arg0, TREE_OPERAND (arg1, 0), 0)
11162 && reorder_operands_p (arg0, TREE_OPERAND (arg1, 1)))
11163 return omit_one_operand (type, arg0, TREE_OPERAND (arg1, 1));
11164 /* X & (Y | X) is (Y, X). */
11165 if (TREE_CODE (arg1) == BIT_IOR_EXPR
11166 && operand_equal_p (arg0, TREE_OPERAND (arg1, 1), 0)
11167 && reorder_operands_p (arg0, TREE_OPERAND (arg1, 0)))
11168 return omit_one_operand (type, arg0, TREE_OPERAND (arg1, 0));
11170 /* Fold (X ^ 1) & 1 as (X & 1) == 0. */
11171 if (TREE_CODE (arg0) == BIT_XOR_EXPR
11172 && integer_onep (TREE_OPERAND (arg0, 1))
11173 && integer_onep (arg1))
11175 tem = TREE_OPERAND (arg0, 0);
11176 return fold_build2 (EQ_EXPR, type,
11177 fold_build2 (BIT_AND_EXPR, TREE_TYPE (tem), tem,
11178 build_int_cst (TREE_TYPE (tem), 1)),
11179 build_int_cst (TREE_TYPE (tem), 0));
11181 /* Fold ~X & 1 as (X & 1) == 0. */
11182 if (TREE_CODE (arg0) == BIT_NOT_EXPR
11183 && integer_onep (arg1))
11185 tem = TREE_OPERAND (arg0, 0);
11186 return fold_build2 (EQ_EXPR, type,
11187 fold_build2 (BIT_AND_EXPR, TREE_TYPE (tem), tem,
11188 build_int_cst (TREE_TYPE (tem), 1)),
11189 build_int_cst (TREE_TYPE (tem), 0));
11192 /* Fold (X ^ Y) & Y as ~X & Y. */
11193 if (TREE_CODE (arg0) == BIT_XOR_EXPR
11194 && operand_equal_p (TREE_OPERAND (arg0, 1), arg1, 0))
11196 tem = fold_convert (type, TREE_OPERAND (arg0, 0));
11197 return fold_build2 (BIT_AND_EXPR, type,
11198 fold_build1 (BIT_NOT_EXPR, type, tem),
11199 fold_convert (type, arg1));
11201 /* Fold (X ^ Y) & X as ~Y & X. */
11202 if (TREE_CODE (arg0) == BIT_XOR_EXPR
11203 && operand_equal_p (TREE_OPERAND (arg0, 0), arg1, 0)
11204 && reorder_operands_p (TREE_OPERAND (arg0, 1), arg1))
11206 tem = fold_convert (type, TREE_OPERAND (arg0, 1));
11207 return fold_build2 (BIT_AND_EXPR, type,
11208 fold_build1 (BIT_NOT_EXPR, type, tem),
11209 fold_convert (type, arg1));
11211 /* Fold X & (X ^ Y) as X & ~Y. */
11212 if (TREE_CODE (arg1) == BIT_XOR_EXPR
11213 && operand_equal_p (arg0, TREE_OPERAND (arg1, 0), 0))
11215 tem = fold_convert (type, TREE_OPERAND (arg1, 1));
11216 return fold_build2 (BIT_AND_EXPR, type,
11217 fold_convert (type, arg0),
11218 fold_build1 (BIT_NOT_EXPR, type, tem));
11220 /* Fold X & (Y ^ X) as ~Y & X. */
11221 if (TREE_CODE (arg1) == BIT_XOR_EXPR
11222 && operand_equal_p (arg0, TREE_OPERAND (arg1, 1), 0)
11223 && reorder_operands_p (arg0, TREE_OPERAND (arg1, 0)))
11225 tem = fold_convert (type, TREE_OPERAND (arg1, 0));
11226 return fold_build2 (BIT_AND_EXPR, type,
11227 fold_build1 (BIT_NOT_EXPR, type, tem),
11228 fold_convert (type, arg0));
11231 t1 = distribute_bit_expr (code, type, arg0, arg1);
11232 if (t1 != NULL_TREE)
11234 /* Simplify ((int)c & 0377) into (int)c, if c is unsigned char. */
11235 if (TREE_CODE (arg1) == INTEGER_CST && TREE_CODE (arg0) == NOP_EXPR
11236 && TYPE_UNSIGNED (TREE_TYPE (TREE_OPERAND (arg0, 0))))
11239 = TYPE_PRECISION (TREE_TYPE (TREE_OPERAND (arg0, 0)));
11241 if (prec < BITS_PER_WORD && prec < HOST_BITS_PER_WIDE_INT
11242 && (~TREE_INT_CST_LOW (arg1)
11243 & (((HOST_WIDE_INT) 1 << prec) - 1)) == 0)
11244 return fold_convert (type, TREE_OPERAND (arg0, 0));
11247 /* Convert (and (not arg0) (not arg1)) to (not (or (arg0) (arg1))).
11249 This results in more efficient code for machines without a NOR
11250 instruction. Combine will canonicalize to the first form
11251 which will allow use of NOR instructions provided by the
11252 backend if they exist. */
11253 if (TREE_CODE (arg0) == BIT_NOT_EXPR
11254 && TREE_CODE (arg1) == BIT_NOT_EXPR)
11256 return fold_build1 (BIT_NOT_EXPR, type,
11257 build2 (BIT_IOR_EXPR, type,
11258 fold_convert (type,
11259 TREE_OPERAND (arg0, 0)),
11260 fold_convert (type,
11261 TREE_OPERAND (arg1, 0))));
11264 /* If arg0 is derived from the address of an object or function, we may
11265 be able to fold this expression using the object or function's
11267 if (POINTER_TYPE_P (TREE_TYPE (arg0)) && host_integerp (arg1, 1))
11269 unsigned HOST_WIDE_INT modulus, residue;
11270 unsigned HOST_WIDE_INT low = TREE_INT_CST_LOW (arg1);
11272 modulus = get_pointer_modulus_and_residue (arg0, &residue,
11273 integer_onep (arg1));
11275 /* This works because modulus is a power of 2. If this weren't the
11276 case, we'd have to replace it by its greatest power-of-2
11277 divisor: modulus & -modulus. */
11279 return build_int_cst (type, residue & low);
11282 /* Fold (X << C1) & C2 into (X << C1) & (C2 | ((1 << C1) - 1))
11283 (X >> C1) & C2 into (X >> C1) & (C2 | ~((type) -1 >> C1))
11284 if the new mask might be further optimized. */
11285 if ((TREE_CODE (arg0) == LSHIFT_EXPR
11286 || TREE_CODE (arg0) == RSHIFT_EXPR)
11287 && host_integerp (TREE_OPERAND (arg0, 1), 1)
11288 && host_integerp (arg1, TYPE_UNSIGNED (TREE_TYPE (arg1)))
11289 && tree_low_cst (TREE_OPERAND (arg0, 1), 1)
11290 < TYPE_PRECISION (TREE_TYPE (arg0))
11291 && TYPE_PRECISION (TREE_TYPE (arg0)) <= HOST_BITS_PER_WIDE_INT
11292 && tree_low_cst (TREE_OPERAND (arg0, 1), 1) > 0)
11294 unsigned int shiftc = tree_low_cst (TREE_OPERAND (arg0, 1), 1);
11295 unsigned HOST_WIDE_INT mask
11296 = tree_low_cst (arg1, TYPE_UNSIGNED (TREE_TYPE (arg1)));
11297 unsigned HOST_WIDE_INT newmask, zerobits = 0;
11298 tree shift_type = TREE_TYPE (arg0);
11300 if (TREE_CODE (arg0) == LSHIFT_EXPR)
11301 zerobits = ((((unsigned HOST_WIDE_INT) 1) << shiftc) - 1);
11302 else if (TREE_CODE (arg0) == RSHIFT_EXPR
11303 && TYPE_PRECISION (TREE_TYPE (arg0))
11304 == GET_MODE_BITSIZE (TYPE_MODE (TREE_TYPE (arg0))))
11306 unsigned int prec = TYPE_PRECISION (TREE_TYPE (arg0));
11307 tree arg00 = TREE_OPERAND (arg0, 0);
11308 /* See if more bits can be proven as zero because of
11310 if (TREE_CODE (arg00) == NOP_EXPR
11311 && TYPE_UNSIGNED (TREE_TYPE (TREE_OPERAND (arg00, 0))))
11313 tree inner_type = TREE_TYPE (TREE_OPERAND (arg00, 0));
11314 if (TYPE_PRECISION (inner_type)
11315 == GET_MODE_BITSIZE (TYPE_MODE (inner_type))
11316 && TYPE_PRECISION (inner_type) < prec)
11318 prec = TYPE_PRECISION (inner_type);
11319 /* See if we can shorten the right shift. */
11321 shift_type = inner_type;
11324 zerobits = ~(unsigned HOST_WIDE_INT) 0;
11325 zerobits >>= HOST_BITS_PER_WIDE_INT - shiftc;
11326 zerobits <<= prec - shiftc;
11327 /* For arithmetic shift if sign bit could be set, zerobits
11328 can contain actually sign bits, so no transformation is
11329 possible, unless MASK masks them all away. In that
11330 case the shift needs to be converted into logical shift. */
11331 if (!TYPE_UNSIGNED (TREE_TYPE (arg0))
11332 && prec == TYPE_PRECISION (TREE_TYPE (arg0)))
11334 if ((mask & zerobits) == 0)
11335 shift_type = unsigned_type_for (TREE_TYPE (arg0));
11341 /* ((X << 16) & 0xff00) is (X, 0). */
11342 if ((mask & zerobits) == mask)
11343 return omit_one_operand (type, build_int_cst (type, 0), arg0);
11345 newmask = mask | zerobits;
11346 if (newmask != mask && (newmask & (newmask + 1)) == 0)
11350 /* Only do the transformation if NEWMASK is some integer
11352 for (prec = BITS_PER_UNIT;
11353 prec < HOST_BITS_PER_WIDE_INT; prec <<= 1)
11354 if (newmask == (((unsigned HOST_WIDE_INT) 1) << prec) - 1)
11356 if (prec < HOST_BITS_PER_WIDE_INT
11357 || newmask == ~(unsigned HOST_WIDE_INT) 0)
11359 if (shift_type != TREE_TYPE (arg0))
11361 tem = fold_build2 (TREE_CODE (arg0), shift_type,
11362 fold_convert (shift_type,
11363 TREE_OPERAND (arg0, 0)),
11364 TREE_OPERAND (arg0, 1));
11365 tem = fold_convert (type, tem);
11369 return fold_build2 (BIT_AND_EXPR, type, tem,
11370 build_int_cst_type (TREE_TYPE (op1),
11379 /* Don't touch a floating-point divide by zero unless the mode
11380 of the constant can represent infinity. */
11381 if (TREE_CODE (arg1) == REAL_CST
11382 && !MODE_HAS_INFINITIES (TYPE_MODE (TREE_TYPE (arg1)))
11383 && real_zerop (arg1))
11386 /* Optimize A / A to 1.0 if we don't care about
11387 NaNs or Infinities. Skip the transformation
11388 for non-real operands. */
11389 if (SCALAR_FLOAT_TYPE_P (TREE_TYPE (arg0))
11390 && ! HONOR_NANS (TYPE_MODE (TREE_TYPE (arg0)))
11391 && ! HONOR_INFINITIES (TYPE_MODE (TREE_TYPE (arg0)))
11392 && operand_equal_p (arg0, arg1, 0))
11394 tree r = build_real (TREE_TYPE (arg0), dconst1);
11396 return omit_two_operands (type, r, arg0, arg1);
11399 /* The complex version of the above A / A optimization. */
11400 if (COMPLEX_FLOAT_TYPE_P (TREE_TYPE (arg0))
11401 && operand_equal_p (arg0, arg1, 0))
11403 tree elem_type = TREE_TYPE (TREE_TYPE (arg0));
11404 if (! HONOR_NANS (TYPE_MODE (elem_type))
11405 && ! HONOR_INFINITIES (TYPE_MODE (elem_type)))
11407 tree r = build_real (elem_type, dconst1);
11408 /* omit_two_operands will call fold_convert for us. */
11409 return omit_two_operands (type, r, arg0, arg1);
11413 /* (-A) / (-B) -> A / B */
11414 if (TREE_CODE (arg0) == NEGATE_EXPR && negate_expr_p (arg1))
11415 return fold_build2 (RDIV_EXPR, type,
11416 TREE_OPERAND (arg0, 0),
11417 negate_expr (arg1));
11418 if (TREE_CODE (arg1) == NEGATE_EXPR && negate_expr_p (arg0))
11419 return fold_build2 (RDIV_EXPR, type,
11420 negate_expr (arg0),
11421 TREE_OPERAND (arg1, 0));
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_onep (arg1))
11426 return non_lvalue (fold_convert (type, arg0));
11428 /* In IEEE floating point, x/-1 is not equivalent to -x for snans. */
11429 if (!HONOR_SNANS (TYPE_MODE (TREE_TYPE (arg0)))
11430 && real_minus_onep (arg1))
11431 return non_lvalue (fold_convert (type, negate_expr (arg0)));
11433 /* If ARG1 is a constant, we can convert this to a multiply by the
11434 reciprocal. This does not have the same rounding properties,
11435 so only do this if -freciprocal-math. We can actually
11436 always safely do it if ARG1 is a power of two, but it's hard to
11437 tell if it is or not in a portable manner. */
11438 if (TREE_CODE (arg1) == REAL_CST)
11440 if (flag_reciprocal_math
11441 && 0 != (tem = const_binop (code, build_real (type, dconst1),
11443 return fold_build2 (MULT_EXPR, type, arg0, tem);
11444 /* Find the reciprocal if optimizing and the result is exact. */
11448 r = TREE_REAL_CST (arg1);
11449 if (exact_real_inverse (TYPE_MODE(TREE_TYPE(arg0)), &r))
11451 tem = build_real (type, r);
11452 return fold_build2 (MULT_EXPR, type,
11453 fold_convert (type, arg0), tem);
11457 /* Convert A/B/C to A/(B*C). */
11458 if (flag_reciprocal_math
11459 && TREE_CODE (arg0) == RDIV_EXPR)
11460 return fold_build2 (RDIV_EXPR, type, TREE_OPERAND (arg0, 0),
11461 fold_build2 (MULT_EXPR, type,
11462 TREE_OPERAND (arg0, 1), arg1));
11464 /* Convert A/(B/C) to (A/B)*C. */
11465 if (flag_reciprocal_math
11466 && TREE_CODE (arg1) == RDIV_EXPR)
11467 return fold_build2 (MULT_EXPR, type,
11468 fold_build2 (RDIV_EXPR, type, arg0,
11469 TREE_OPERAND (arg1, 0)),
11470 TREE_OPERAND (arg1, 1));
11472 /* Convert C1/(X*C2) into (C1/C2)/X. */
11473 if (flag_reciprocal_math
11474 && TREE_CODE (arg1) == MULT_EXPR
11475 && TREE_CODE (arg0) == REAL_CST
11476 && TREE_CODE (TREE_OPERAND (arg1, 1)) == REAL_CST)
11478 tree tem = const_binop (RDIV_EXPR, arg0,
11479 TREE_OPERAND (arg1, 1), 0);
11481 return fold_build2 (RDIV_EXPR, type, tem,
11482 TREE_OPERAND (arg1, 0));
11485 if (flag_unsafe_math_optimizations)
11487 enum built_in_function fcode0 = builtin_mathfn_code (arg0);
11488 enum built_in_function fcode1 = builtin_mathfn_code (arg1);
11490 /* Optimize sin(x)/cos(x) as tan(x). */
11491 if (((fcode0 == BUILT_IN_SIN && fcode1 == BUILT_IN_COS)
11492 || (fcode0 == BUILT_IN_SINF && fcode1 == BUILT_IN_COSF)
11493 || (fcode0 == BUILT_IN_SINL && fcode1 == BUILT_IN_COSL))
11494 && operand_equal_p (CALL_EXPR_ARG (arg0, 0),
11495 CALL_EXPR_ARG (arg1, 0), 0))
11497 tree tanfn = mathfn_built_in (type, BUILT_IN_TAN);
11499 if (tanfn != NULL_TREE)
11500 return build_call_expr (tanfn, 1, CALL_EXPR_ARG (arg0, 0));
11503 /* Optimize cos(x)/sin(x) as 1.0/tan(x). */
11504 if (((fcode0 == BUILT_IN_COS && fcode1 == BUILT_IN_SIN)
11505 || (fcode0 == BUILT_IN_COSF && fcode1 == BUILT_IN_SINF)
11506 || (fcode0 == BUILT_IN_COSL && fcode1 == BUILT_IN_SINL))
11507 && operand_equal_p (CALL_EXPR_ARG (arg0, 0),
11508 CALL_EXPR_ARG (arg1, 0), 0))
11510 tree tanfn = mathfn_built_in (type, BUILT_IN_TAN);
11512 if (tanfn != NULL_TREE)
11514 tree tmp = build_call_expr (tanfn, 1, CALL_EXPR_ARG (arg0, 0));
11515 return fold_build2 (RDIV_EXPR, type,
11516 build_real (type, dconst1), tmp);
11520 /* Optimize sin(x)/tan(x) as cos(x) if we don't care about
11521 NaNs or Infinities. */
11522 if (((fcode0 == BUILT_IN_SIN && fcode1 == BUILT_IN_TAN)
11523 || (fcode0 == BUILT_IN_SINF && fcode1 == BUILT_IN_TANF)
11524 || (fcode0 == BUILT_IN_SINL && fcode1 == BUILT_IN_TANL)))
11526 tree arg00 = CALL_EXPR_ARG (arg0, 0);
11527 tree arg01 = CALL_EXPR_ARG (arg1, 0);
11529 if (! HONOR_NANS (TYPE_MODE (TREE_TYPE (arg00)))
11530 && ! HONOR_INFINITIES (TYPE_MODE (TREE_TYPE (arg00)))
11531 && operand_equal_p (arg00, arg01, 0))
11533 tree cosfn = mathfn_built_in (type, BUILT_IN_COS);
11535 if (cosfn != NULL_TREE)
11536 return build_call_expr (cosfn, 1, arg00);
11540 /* Optimize tan(x)/sin(x) as 1.0/cos(x) if we don't care about
11541 NaNs or Infinities. */
11542 if (((fcode0 == BUILT_IN_TAN && fcode1 == BUILT_IN_SIN)
11543 || (fcode0 == BUILT_IN_TANF && fcode1 == BUILT_IN_SINF)
11544 || (fcode0 == BUILT_IN_TANL && fcode1 == BUILT_IN_SINL)))
11546 tree arg00 = CALL_EXPR_ARG (arg0, 0);
11547 tree arg01 = CALL_EXPR_ARG (arg1, 0);
11549 if (! HONOR_NANS (TYPE_MODE (TREE_TYPE (arg00)))
11550 && ! HONOR_INFINITIES (TYPE_MODE (TREE_TYPE (arg00)))
11551 && operand_equal_p (arg00, arg01, 0))
11553 tree cosfn = mathfn_built_in (type, BUILT_IN_COS);
11555 if (cosfn != NULL_TREE)
11557 tree tmp = build_call_expr (cosfn, 1, arg00);
11558 return fold_build2 (RDIV_EXPR, type,
11559 build_real (type, dconst1),
11565 /* Optimize pow(x,c)/x as pow(x,c-1). */
11566 if (fcode0 == BUILT_IN_POW
11567 || fcode0 == BUILT_IN_POWF
11568 || fcode0 == BUILT_IN_POWL)
11570 tree arg00 = CALL_EXPR_ARG (arg0, 0);
11571 tree arg01 = CALL_EXPR_ARG (arg0, 1);
11572 if (TREE_CODE (arg01) == REAL_CST
11573 && !TREE_OVERFLOW (arg01)
11574 && operand_equal_p (arg1, arg00, 0))
11576 tree powfn = TREE_OPERAND (CALL_EXPR_FN (arg0), 0);
11580 c = TREE_REAL_CST (arg01);
11581 real_arithmetic (&c, MINUS_EXPR, &c, &dconst1);
11582 arg = build_real (type, c);
11583 return build_call_expr (powfn, 2, arg1, arg);
11587 /* Optimize a/root(b/c) into a*root(c/b). */
11588 if (BUILTIN_ROOT_P (fcode1))
11590 tree rootarg = CALL_EXPR_ARG (arg1, 0);
11592 if (TREE_CODE (rootarg) == RDIV_EXPR)
11594 tree rootfn = TREE_OPERAND (CALL_EXPR_FN (arg1), 0);
11595 tree b = TREE_OPERAND (rootarg, 0);
11596 tree c = TREE_OPERAND (rootarg, 1);
11598 tree tmp = fold_build2 (RDIV_EXPR, type, c, b);
11600 tmp = build_call_expr (rootfn, 1, tmp);
11601 return fold_build2 (MULT_EXPR, type, arg0, tmp);
11605 /* Optimize x/expN(y) into x*expN(-y). */
11606 if (BUILTIN_EXPONENT_P (fcode1))
11608 tree expfn = TREE_OPERAND (CALL_EXPR_FN (arg1), 0);
11609 tree arg = negate_expr (CALL_EXPR_ARG (arg1, 0));
11610 arg1 = build_call_expr (expfn, 1, fold_convert (type, arg));
11611 return fold_build2 (MULT_EXPR, type, arg0, arg1);
11614 /* Optimize x/pow(y,z) into x*pow(y,-z). */
11615 if (fcode1 == BUILT_IN_POW
11616 || fcode1 == BUILT_IN_POWF
11617 || fcode1 == BUILT_IN_POWL)
11619 tree powfn = TREE_OPERAND (CALL_EXPR_FN (arg1), 0);
11620 tree arg10 = CALL_EXPR_ARG (arg1, 0);
11621 tree arg11 = CALL_EXPR_ARG (arg1, 1);
11622 tree neg11 = fold_convert (type, negate_expr (arg11));
11623 arg1 = build_call_expr (powfn, 2, arg10, neg11);
11624 return fold_build2 (MULT_EXPR, type, arg0, arg1);
11629 case TRUNC_DIV_EXPR:
11630 case FLOOR_DIV_EXPR:
11631 /* Simplify A / (B << N) where A and B are positive and B is
11632 a power of 2, to A >> (N + log2(B)). */
11633 strict_overflow_p = false;
11634 if (TREE_CODE (arg1) == LSHIFT_EXPR
11635 && (TYPE_UNSIGNED (type)
11636 || tree_expr_nonnegative_warnv_p (op0, &strict_overflow_p)))
11638 tree sval = TREE_OPERAND (arg1, 0);
11639 if (integer_pow2p (sval) && tree_int_cst_sgn (sval) > 0)
11641 tree sh_cnt = TREE_OPERAND (arg1, 1);
11642 unsigned long pow2 = exact_log2 (TREE_INT_CST_LOW (sval));
11644 if (strict_overflow_p)
11645 fold_overflow_warning (("assuming signed overflow does not "
11646 "occur when simplifying A / (B << N)"),
11647 WARN_STRICT_OVERFLOW_MISC);
11649 sh_cnt = fold_build2 (PLUS_EXPR, TREE_TYPE (sh_cnt),
11650 sh_cnt, build_int_cst (NULL_TREE, pow2));
11651 return fold_build2 (RSHIFT_EXPR, type,
11652 fold_convert (type, arg0), sh_cnt);
11656 /* For unsigned integral types, FLOOR_DIV_EXPR is the same as
11657 TRUNC_DIV_EXPR. Rewrite into the latter in this case. */
11658 if (INTEGRAL_TYPE_P (type)
11659 && TYPE_UNSIGNED (type)
11660 && code == FLOOR_DIV_EXPR)
11661 return fold_build2 (TRUNC_DIV_EXPR, type, op0, op1);
11665 case ROUND_DIV_EXPR:
11666 case CEIL_DIV_EXPR:
11667 case EXACT_DIV_EXPR:
11668 if (integer_onep (arg1))
11669 return non_lvalue (fold_convert (type, arg0));
11670 if (integer_zerop (arg1))
11672 /* X / -1 is -X. */
11673 if (!TYPE_UNSIGNED (type)
11674 && TREE_CODE (arg1) == INTEGER_CST
11675 && TREE_INT_CST_LOW (arg1) == (unsigned HOST_WIDE_INT) -1
11676 && TREE_INT_CST_HIGH (arg1) == -1)
11677 return fold_convert (type, negate_expr (arg0));
11679 /* Convert -A / -B to A / B when the type is signed and overflow is
11681 if ((!INTEGRAL_TYPE_P (type) || TYPE_OVERFLOW_UNDEFINED (type))
11682 && TREE_CODE (arg0) == NEGATE_EXPR
11683 && negate_expr_p (arg1))
11685 if (INTEGRAL_TYPE_P (type))
11686 fold_overflow_warning (("assuming signed overflow does not occur "
11687 "when distributing negation across "
11689 WARN_STRICT_OVERFLOW_MISC);
11690 return fold_build2 (code, type,
11691 fold_convert (type, TREE_OPERAND (arg0, 0)),
11692 fold_convert (type, negate_expr (arg1)));
11694 if ((!INTEGRAL_TYPE_P (type) || TYPE_OVERFLOW_UNDEFINED (type))
11695 && TREE_CODE (arg1) == NEGATE_EXPR
11696 && negate_expr_p (arg0))
11698 if (INTEGRAL_TYPE_P (type))
11699 fold_overflow_warning (("assuming signed overflow does not occur "
11700 "when distributing negation across "
11702 WARN_STRICT_OVERFLOW_MISC);
11703 return fold_build2 (code, type,
11704 fold_convert (type, negate_expr (arg0)),
11705 fold_convert (type, TREE_OPERAND (arg1, 0)));
11708 /* If arg0 is a multiple of arg1, then rewrite to the fastest div
11709 operation, EXACT_DIV_EXPR.
11711 Note that only CEIL_DIV_EXPR and FLOOR_DIV_EXPR are rewritten now.
11712 At one time others generated faster code, it's not clear if they do
11713 after the last round to changes to the DIV code in expmed.c. */
11714 if ((code == CEIL_DIV_EXPR || code == FLOOR_DIV_EXPR)
11715 && multiple_of_p (type, arg0, arg1))
11716 return fold_build2 (EXACT_DIV_EXPR, type, arg0, arg1);
11718 strict_overflow_p = false;
11719 if (TREE_CODE (arg1) == INTEGER_CST
11720 && 0 != (tem = extract_muldiv (op0, arg1, code, NULL_TREE,
11721 &strict_overflow_p)))
11723 if (strict_overflow_p)
11724 fold_overflow_warning (("assuming signed overflow does not occur "
11725 "when simplifying division"),
11726 WARN_STRICT_OVERFLOW_MISC);
11727 return fold_convert (type, tem);
11732 case CEIL_MOD_EXPR:
11733 case FLOOR_MOD_EXPR:
11734 case ROUND_MOD_EXPR:
11735 case TRUNC_MOD_EXPR:
11736 /* X % 1 is always zero, but be sure to preserve any side
11738 if (integer_onep (arg1))
11739 return omit_one_operand (type, integer_zero_node, arg0);
11741 /* X % 0, return X % 0 unchanged so that we can get the
11742 proper warnings and errors. */
11743 if (integer_zerop (arg1))
11746 /* 0 % X is always zero, but be sure to preserve any side
11747 effects in X. Place this after checking for X == 0. */
11748 if (integer_zerop (arg0))
11749 return omit_one_operand (type, integer_zero_node, arg1);
11751 /* X % -1 is zero. */
11752 if (!TYPE_UNSIGNED (type)
11753 && TREE_CODE (arg1) == INTEGER_CST
11754 && TREE_INT_CST_LOW (arg1) == (unsigned HOST_WIDE_INT) -1
11755 && TREE_INT_CST_HIGH (arg1) == -1)
11756 return omit_one_operand (type, integer_zero_node, arg0);
11758 /* Optimize TRUNC_MOD_EXPR by a power of two into a BIT_AND_EXPR,
11759 i.e. "X % C" into "X & (C - 1)", if X and C are positive. */
11760 strict_overflow_p = false;
11761 if ((code == TRUNC_MOD_EXPR || code == FLOOR_MOD_EXPR)
11762 && (TYPE_UNSIGNED (type)
11763 || tree_expr_nonnegative_warnv_p (op0, &strict_overflow_p)))
11766 /* Also optimize A % (C << N) where C is a power of 2,
11767 to A & ((C << N) - 1). */
11768 if (TREE_CODE (arg1) == LSHIFT_EXPR)
11769 c = TREE_OPERAND (arg1, 0);
11771 if (integer_pow2p (c) && tree_int_cst_sgn (c) > 0)
11773 tree mask = fold_build2 (MINUS_EXPR, TREE_TYPE (arg1), arg1,
11774 build_int_cst (TREE_TYPE (arg1), 1));
11775 if (strict_overflow_p)
11776 fold_overflow_warning (("assuming signed overflow does not "
11777 "occur when simplifying "
11778 "X % (power of two)"),
11779 WARN_STRICT_OVERFLOW_MISC);
11780 return fold_build2 (BIT_AND_EXPR, type,
11781 fold_convert (type, arg0),
11782 fold_convert (type, mask));
11786 /* X % -C is the same as X % C. */
11787 if (code == TRUNC_MOD_EXPR
11788 && !TYPE_UNSIGNED (type)
11789 && TREE_CODE (arg1) == INTEGER_CST
11790 && !TREE_OVERFLOW (arg1)
11791 && TREE_INT_CST_HIGH (arg1) < 0
11792 && !TYPE_OVERFLOW_TRAPS (type)
11793 /* Avoid this transformation if C is INT_MIN, i.e. C == -C. */
11794 && !sign_bit_p (arg1, arg1))
11795 return fold_build2 (code, type, fold_convert (type, arg0),
11796 fold_convert (type, negate_expr (arg1)));
11798 /* X % -Y is the same as X % Y. */
11799 if (code == TRUNC_MOD_EXPR
11800 && !TYPE_UNSIGNED (type)
11801 && TREE_CODE (arg1) == NEGATE_EXPR
11802 && !TYPE_OVERFLOW_TRAPS (type))
11803 return fold_build2 (code, type, fold_convert (type, arg0),
11804 fold_convert (type, TREE_OPERAND (arg1, 0)));
11806 if (TREE_CODE (arg1) == INTEGER_CST
11807 && 0 != (tem = extract_muldiv (op0, arg1, code, NULL_TREE,
11808 &strict_overflow_p)))
11810 if (strict_overflow_p)
11811 fold_overflow_warning (("assuming signed overflow does not occur "
11812 "when simplifying modulus"),
11813 WARN_STRICT_OVERFLOW_MISC);
11814 return fold_convert (type, tem);
11821 if (integer_all_onesp (arg0))
11822 return omit_one_operand (type, arg0, arg1);
11826 /* Optimize -1 >> x for arithmetic right shifts. */
11827 if (integer_all_onesp (arg0) && !TYPE_UNSIGNED (type)
11828 && tree_expr_nonnegative_p (arg1))
11829 return omit_one_operand (type, arg0, arg1);
11830 /* ... fall through ... */
11834 if (integer_zerop (arg1))
11835 return non_lvalue (fold_convert (type, arg0));
11836 if (integer_zerop (arg0))
11837 return omit_one_operand (type, arg0, arg1);
11839 /* Since negative shift count is not well-defined,
11840 don't try to compute it in the compiler. */
11841 if (TREE_CODE (arg1) == INTEGER_CST && tree_int_cst_sgn (arg1) < 0)
11844 /* Turn (a OP c1) OP c2 into a OP (c1+c2). */
11845 if (TREE_CODE (op0) == code && host_integerp (arg1, false)
11846 && TREE_INT_CST_LOW (arg1) < TYPE_PRECISION (type)
11847 && host_integerp (TREE_OPERAND (arg0, 1), false)
11848 && TREE_INT_CST_LOW (TREE_OPERAND (arg0, 1)) < TYPE_PRECISION (type))
11850 HOST_WIDE_INT low = (TREE_INT_CST_LOW (TREE_OPERAND (arg0, 1))
11851 + TREE_INT_CST_LOW (arg1));
11853 /* Deal with a OP (c1 + c2) being undefined but (a OP c1) OP c2
11854 being well defined. */
11855 if (low >= TYPE_PRECISION (type))
11857 if (code == LROTATE_EXPR || code == RROTATE_EXPR)
11858 low = low % TYPE_PRECISION (type);
11859 else if (TYPE_UNSIGNED (type) || code == LSHIFT_EXPR)
11860 return build_int_cst (type, 0);
11862 low = TYPE_PRECISION (type) - 1;
11865 return fold_build2 (code, type, TREE_OPERAND (arg0, 0),
11866 build_int_cst (type, low));
11869 /* Transform (x >> c) << c into x & (-1<<c), or transform (x << c) >> c
11870 into x & ((unsigned)-1 >> c) for unsigned types. */
11871 if (((code == LSHIFT_EXPR && TREE_CODE (arg0) == RSHIFT_EXPR)
11872 || (TYPE_UNSIGNED (type)
11873 && code == RSHIFT_EXPR && TREE_CODE (arg0) == LSHIFT_EXPR))
11874 && host_integerp (arg1, false)
11875 && TREE_INT_CST_LOW (arg1) < TYPE_PRECISION (type)
11876 && host_integerp (TREE_OPERAND (arg0, 1), false)
11877 && TREE_INT_CST_LOW (TREE_OPERAND (arg0, 1)) < TYPE_PRECISION (type))
11879 HOST_WIDE_INT low0 = TREE_INT_CST_LOW (TREE_OPERAND (arg0, 1));
11880 HOST_WIDE_INT low1 = TREE_INT_CST_LOW (arg1);
11886 arg00 = fold_convert (type, TREE_OPERAND (arg0, 0));
11888 lshift = build_int_cst (type, -1);
11889 lshift = int_const_binop (code, lshift, arg1, 0);
11891 return fold_build2 (BIT_AND_EXPR, type, arg00, lshift);
11895 /* Rewrite an LROTATE_EXPR by a constant into an
11896 RROTATE_EXPR by a new constant. */
11897 if (code == LROTATE_EXPR && TREE_CODE (arg1) == INTEGER_CST)
11899 tree tem = build_int_cst (TREE_TYPE (arg1),
11900 TYPE_PRECISION (type));
11901 tem = const_binop (MINUS_EXPR, tem, arg1, 0);
11902 return fold_build2 (RROTATE_EXPR, type, op0, tem);
11905 /* If we have a rotate of a bit operation with the rotate count and
11906 the second operand of the bit operation both constant,
11907 permute the two operations. */
11908 if (code == RROTATE_EXPR && TREE_CODE (arg1) == INTEGER_CST
11909 && (TREE_CODE (arg0) == BIT_AND_EXPR
11910 || TREE_CODE (arg0) == BIT_IOR_EXPR
11911 || TREE_CODE (arg0) == BIT_XOR_EXPR)
11912 && TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST)
11913 return fold_build2 (TREE_CODE (arg0), type,
11914 fold_build2 (code, type,
11915 TREE_OPERAND (arg0, 0), arg1),
11916 fold_build2 (code, type,
11917 TREE_OPERAND (arg0, 1), arg1));
11919 /* Two consecutive rotates adding up to the precision of the
11920 type can be ignored. */
11921 if (code == RROTATE_EXPR && TREE_CODE (arg1) == INTEGER_CST
11922 && TREE_CODE (arg0) == RROTATE_EXPR
11923 && TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST
11924 && TREE_INT_CST_HIGH (arg1) == 0
11925 && TREE_INT_CST_HIGH (TREE_OPERAND (arg0, 1)) == 0
11926 && ((TREE_INT_CST_LOW (arg1)
11927 + TREE_INT_CST_LOW (TREE_OPERAND (arg0, 1)))
11928 == (unsigned int) TYPE_PRECISION (type)))
11929 return TREE_OPERAND (arg0, 0);
11931 /* Fold (X & C2) << C1 into (X << C1) & (C2 << C1)
11932 (X & C2) >> C1 into (X >> C1) & (C2 >> C1)
11933 if the latter can be further optimized. */
11934 if ((code == LSHIFT_EXPR || code == RSHIFT_EXPR)
11935 && TREE_CODE (arg0) == BIT_AND_EXPR
11936 && TREE_CODE (arg1) == INTEGER_CST
11937 && TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST)
11939 tree mask = fold_build2 (code, type,
11940 fold_convert (type, TREE_OPERAND (arg0, 1)),
11942 tree shift = fold_build2 (code, type,
11943 fold_convert (type, TREE_OPERAND (arg0, 0)),
11945 tem = fold_binary (BIT_AND_EXPR, type, shift, mask);
11953 if (operand_equal_p (arg0, arg1, 0))
11954 return omit_one_operand (type, arg0, arg1);
11955 if (INTEGRAL_TYPE_P (type)
11956 && operand_equal_p (arg1, TYPE_MIN_VALUE (type), OEP_ONLY_CONST))
11957 return omit_one_operand (type, arg1, arg0);
11958 tem = fold_minmax (MIN_EXPR, type, arg0, arg1);
11964 if (operand_equal_p (arg0, arg1, 0))
11965 return omit_one_operand (type, arg0, arg1);
11966 if (INTEGRAL_TYPE_P (type)
11967 && TYPE_MAX_VALUE (type)
11968 && operand_equal_p (arg1, TYPE_MAX_VALUE (type), OEP_ONLY_CONST))
11969 return omit_one_operand (type, arg1, arg0);
11970 tem = fold_minmax (MAX_EXPR, type, arg0, arg1);
11975 case TRUTH_ANDIF_EXPR:
11976 /* Note that the operands of this must be ints
11977 and their values must be 0 or 1.
11978 ("true" is a fixed value perhaps depending on the language.) */
11979 /* If first arg is constant zero, return it. */
11980 if (integer_zerop (arg0))
11981 return fold_convert (type, arg0);
11982 case TRUTH_AND_EXPR:
11983 /* If either arg is constant true, drop it. */
11984 if (TREE_CODE (arg0) == INTEGER_CST && ! integer_zerop (arg0))
11985 return non_lvalue (fold_convert (type, arg1));
11986 if (TREE_CODE (arg1) == INTEGER_CST && ! integer_zerop (arg1)
11987 /* Preserve sequence points. */
11988 && (code != TRUTH_ANDIF_EXPR || ! TREE_SIDE_EFFECTS (arg0)))
11989 return non_lvalue (fold_convert (type, arg0));
11990 /* If second arg is constant zero, result is zero, but first arg
11991 must be evaluated. */
11992 if (integer_zerop (arg1))
11993 return omit_one_operand (type, arg1, arg0);
11994 /* Likewise for first arg, but note that only the TRUTH_AND_EXPR
11995 case will be handled here. */
11996 if (integer_zerop (arg0))
11997 return omit_one_operand (type, arg0, arg1);
11999 /* !X && X is always false. */
12000 if (TREE_CODE (arg0) == TRUTH_NOT_EXPR
12001 && operand_equal_p (TREE_OPERAND (arg0, 0), arg1, 0))
12002 return omit_one_operand (type, integer_zero_node, arg1);
12003 /* X && !X is always false. */
12004 if (TREE_CODE (arg1) == TRUTH_NOT_EXPR
12005 && operand_equal_p (arg0, TREE_OPERAND (arg1, 0), 0))
12006 return omit_one_operand (type, integer_zero_node, arg0);
12008 /* A < X && A + 1 > Y ==> A < X && A >= Y. Normally A + 1 > Y
12009 means A >= Y && A != MAX, but in this case we know that
12012 if (!TREE_SIDE_EFFECTS (arg0)
12013 && !TREE_SIDE_EFFECTS (arg1))
12015 tem = fold_to_nonsharp_ineq_using_bound (arg0, arg1);
12016 if (tem && !operand_equal_p (tem, arg0, 0))
12017 return fold_build2 (code, type, tem, arg1);
12019 tem = fold_to_nonsharp_ineq_using_bound (arg1, arg0);
12020 if (tem && !operand_equal_p (tem, arg1, 0))
12021 return fold_build2 (code, type, arg0, tem);
12025 /* We only do these simplifications if we are optimizing. */
12029 /* Check for things like (A || B) && (A || C). We can convert this
12030 to A || (B && C). Note that either operator can be any of the four
12031 truth and/or operations and the transformation will still be
12032 valid. Also note that we only care about order for the
12033 ANDIF and ORIF operators. If B contains side effects, this
12034 might change the truth-value of A. */
12035 if (TREE_CODE (arg0) == TREE_CODE (arg1)
12036 && (TREE_CODE (arg0) == TRUTH_ANDIF_EXPR
12037 || TREE_CODE (arg0) == TRUTH_ORIF_EXPR
12038 || TREE_CODE (arg0) == TRUTH_AND_EXPR
12039 || TREE_CODE (arg0) == TRUTH_OR_EXPR)
12040 && ! TREE_SIDE_EFFECTS (TREE_OPERAND (arg0, 1)))
12042 tree a00 = TREE_OPERAND (arg0, 0);
12043 tree a01 = TREE_OPERAND (arg0, 1);
12044 tree a10 = TREE_OPERAND (arg1, 0);
12045 tree a11 = TREE_OPERAND (arg1, 1);
12046 int commutative = ((TREE_CODE (arg0) == TRUTH_OR_EXPR
12047 || TREE_CODE (arg0) == TRUTH_AND_EXPR)
12048 && (code == TRUTH_AND_EXPR
12049 || code == TRUTH_OR_EXPR));
12051 if (operand_equal_p (a00, a10, 0))
12052 return fold_build2 (TREE_CODE (arg0), type, a00,
12053 fold_build2 (code, type, a01, a11));
12054 else if (commutative && operand_equal_p (a00, a11, 0))
12055 return fold_build2 (TREE_CODE (arg0), type, a00,
12056 fold_build2 (code, type, a01, a10));
12057 else if (commutative && operand_equal_p (a01, a10, 0))
12058 return fold_build2 (TREE_CODE (arg0), type, a01,
12059 fold_build2 (code, type, a00, a11));
12061 /* This case if tricky because we must either have commutative
12062 operators or else A10 must not have side-effects. */
12064 else if ((commutative || ! TREE_SIDE_EFFECTS (a10))
12065 && operand_equal_p (a01, a11, 0))
12066 return fold_build2 (TREE_CODE (arg0), type,
12067 fold_build2 (code, type, a00, a10),
12071 /* See if we can build a range comparison. */
12072 if (0 != (tem = fold_range_test (code, type, op0, op1)))
12075 /* Check for the possibility of merging component references. If our
12076 lhs is another similar operation, try to merge its rhs with our
12077 rhs. Then try to merge our lhs and rhs. */
12078 if (TREE_CODE (arg0) == code
12079 && 0 != (tem = fold_truthop (code, type,
12080 TREE_OPERAND (arg0, 1), arg1)))
12081 return fold_build2 (code, type, TREE_OPERAND (arg0, 0), tem);
12083 if ((tem = fold_truthop (code, type, arg0, arg1)) != 0)
12088 case TRUTH_ORIF_EXPR:
12089 /* Note that the operands of this must be ints
12090 and their values must be 0 or true.
12091 ("true" is a fixed value perhaps depending on the language.) */
12092 /* If first arg is constant true, return it. */
12093 if (TREE_CODE (arg0) == INTEGER_CST && ! integer_zerop (arg0))
12094 return fold_convert (type, arg0);
12095 case TRUTH_OR_EXPR:
12096 /* If either arg is constant zero, drop it. */
12097 if (TREE_CODE (arg0) == INTEGER_CST && integer_zerop (arg0))
12098 return non_lvalue (fold_convert (type, arg1));
12099 if (TREE_CODE (arg1) == INTEGER_CST && integer_zerop (arg1)
12100 /* Preserve sequence points. */
12101 && (code != TRUTH_ORIF_EXPR || ! TREE_SIDE_EFFECTS (arg0)))
12102 return non_lvalue (fold_convert (type, arg0));
12103 /* If second arg is constant true, result is true, but we must
12104 evaluate first arg. */
12105 if (TREE_CODE (arg1) == INTEGER_CST && ! integer_zerop (arg1))
12106 return omit_one_operand (type, arg1, arg0);
12107 /* Likewise for first arg, but note this only occurs here for
12109 if (TREE_CODE (arg0) == INTEGER_CST && ! integer_zerop (arg0))
12110 return omit_one_operand (type, arg0, arg1);
12112 /* !X || X is always true. */
12113 if (TREE_CODE (arg0) == TRUTH_NOT_EXPR
12114 && operand_equal_p (TREE_OPERAND (arg0, 0), arg1, 0))
12115 return omit_one_operand (type, integer_one_node, arg1);
12116 /* X || !X is always true. */
12117 if (TREE_CODE (arg1) == TRUTH_NOT_EXPR
12118 && operand_equal_p (arg0, TREE_OPERAND (arg1, 0), 0))
12119 return omit_one_operand (type, integer_one_node, arg0);
12123 case TRUTH_XOR_EXPR:
12124 /* If the second arg is constant zero, drop it. */
12125 if (integer_zerop (arg1))
12126 return non_lvalue (fold_convert (type, arg0));
12127 /* If the second arg is constant true, this is a logical inversion. */
12128 if (integer_onep (arg1))
12130 /* Only call invert_truthvalue if operand is a truth value. */
12131 if (TREE_CODE (TREE_TYPE (arg0)) != BOOLEAN_TYPE)
12132 tem = fold_build1 (TRUTH_NOT_EXPR, TREE_TYPE (arg0), arg0);
12134 tem = invert_truthvalue (arg0);
12135 return non_lvalue (fold_convert (type, tem));
12137 /* Identical arguments cancel to zero. */
12138 if (operand_equal_p (arg0, arg1, 0))
12139 return omit_one_operand (type, integer_zero_node, arg0);
12141 /* !X ^ X is always true. */
12142 if (TREE_CODE (arg0) == TRUTH_NOT_EXPR
12143 && operand_equal_p (TREE_OPERAND (arg0, 0), arg1, 0))
12144 return omit_one_operand (type, integer_one_node, arg1);
12146 /* X ^ !X is always true. */
12147 if (TREE_CODE (arg1) == TRUTH_NOT_EXPR
12148 && operand_equal_p (arg0, TREE_OPERAND (arg1, 0), 0))
12149 return omit_one_operand (type, integer_one_node, arg0);
12155 tem = fold_comparison (code, type, op0, op1);
12156 if (tem != NULL_TREE)
12159 /* bool_var != 0 becomes bool_var. */
12160 if (TREE_CODE (TREE_TYPE (arg0)) == BOOLEAN_TYPE && integer_zerop (arg1)
12161 && code == NE_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 == EQ_EXPR)
12167 return non_lvalue (fold_convert (type, arg0));
12169 /* bool_var != 1 becomes !bool_var. */
12170 if (TREE_CODE (TREE_TYPE (arg0)) == BOOLEAN_TYPE && integer_onep (arg1)
12171 && code == NE_EXPR)
12172 return fold_build1 (TRUTH_NOT_EXPR, type, fold_convert (type, arg0));
12174 /* bool_var == 0 becomes !bool_var. */
12175 if (TREE_CODE (TREE_TYPE (arg0)) == BOOLEAN_TYPE && integer_zerop (arg1)
12176 && code == EQ_EXPR)
12177 return fold_build1 (TRUTH_NOT_EXPR, type, fold_convert (type, arg0));
12179 /* If this is an equality comparison of the address of two non-weak,
12180 unaliased symbols neither of which are extern (since we do not
12181 have access to attributes for externs), then we know the result. */
12182 if (TREE_CODE (arg0) == ADDR_EXPR
12183 && VAR_OR_FUNCTION_DECL_P (TREE_OPERAND (arg0, 0))
12184 && ! DECL_WEAK (TREE_OPERAND (arg0, 0))
12185 && ! lookup_attribute ("alias",
12186 DECL_ATTRIBUTES (TREE_OPERAND (arg0, 0)))
12187 && ! DECL_EXTERNAL (TREE_OPERAND (arg0, 0))
12188 && TREE_CODE (arg1) == ADDR_EXPR
12189 && VAR_OR_FUNCTION_DECL_P (TREE_OPERAND (arg1, 0))
12190 && ! DECL_WEAK (TREE_OPERAND (arg1, 0))
12191 && ! lookup_attribute ("alias",
12192 DECL_ATTRIBUTES (TREE_OPERAND (arg1, 0)))
12193 && ! DECL_EXTERNAL (TREE_OPERAND (arg1, 0)))
12195 /* We know that we're looking at the address of two
12196 non-weak, unaliased, static _DECL nodes.
12198 It is both wasteful and incorrect to call operand_equal_p
12199 to compare the two ADDR_EXPR nodes. It is wasteful in that
12200 all we need to do is test pointer equality for the arguments
12201 to the two ADDR_EXPR nodes. It is incorrect to use
12202 operand_equal_p as that function is NOT equivalent to a
12203 C equality test. It can in fact return false for two
12204 objects which would test as equal using the C equality
12206 bool equal = TREE_OPERAND (arg0, 0) == TREE_OPERAND (arg1, 0);
12207 return constant_boolean_node (equal
12208 ? code == EQ_EXPR : code != EQ_EXPR,
12212 /* If this is an EQ or NE comparison of a constant with a PLUS_EXPR or
12213 a MINUS_EXPR of a constant, we can convert it into a comparison with
12214 a revised constant as long as no overflow occurs. */
12215 if (TREE_CODE (arg1) == INTEGER_CST
12216 && (TREE_CODE (arg0) == PLUS_EXPR
12217 || TREE_CODE (arg0) == MINUS_EXPR)
12218 && TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST
12219 && 0 != (tem = const_binop (TREE_CODE (arg0) == PLUS_EXPR
12220 ? MINUS_EXPR : PLUS_EXPR,
12221 fold_convert (TREE_TYPE (arg0), arg1),
12222 TREE_OPERAND (arg0, 1), 0))
12223 && !TREE_OVERFLOW (tem))
12224 return fold_build2 (code, type, TREE_OPERAND (arg0, 0), tem);
12226 /* Similarly for a NEGATE_EXPR. */
12227 if (TREE_CODE (arg0) == NEGATE_EXPR
12228 && TREE_CODE (arg1) == INTEGER_CST
12229 && 0 != (tem = negate_expr (arg1))
12230 && TREE_CODE (tem) == INTEGER_CST
12231 && !TREE_OVERFLOW (tem))
12232 return fold_build2 (code, type, TREE_OPERAND (arg0, 0), tem);
12234 /* Similarly for a BIT_XOR_EXPR; X ^ C1 == C2 is X == (C1 ^ C2). */
12235 if (TREE_CODE (arg0) == BIT_XOR_EXPR
12236 && TREE_CODE (arg1) == INTEGER_CST
12237 && TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST)
12238 return fold_build2 (code, type, TREE_OPERAND (arg0, 0),
12239 fold_build2 (BIT_XOR_EXPR, TREE_TYPE (arg0),
12240 fold_convert (TREE_TYPE (arg0), arg1),
12241 TREE_OPERAND (arg0, 1)));
12243 /* Transform comparisons of the form X +- Y CMP X to Y CMP 0. */
12244 if ((TREE_CODE (arg0) == PLUS_EXPR
12245 || TREE_CODE (arg0) == POINTER_PLUS_EXPR
12246 || TREE_CODE (arg0) == MINUS_EXPR)
12247 && operand_equal_p (TREE_OPERAND (arg0, 0), arg1, 0)
12248 && (INTEGRAL_TYPE_P (TREE_TYPE (arg0))
12249 || POINTER_TYPE_P (TREE_TYPE (arg0))))
12251 tree val = TREE_OPERAND (arg0, 1);
12252 return omit_two_operands (type,
12253 fold_build2 (code, type,
12255 build_int_cst (TREE_TYPE (val),
12257 TREE_OPERAND (arg0, 0), arg1);
12260 /* Transform comparisons of the form C - X CMP X if C % 2 == 1. */
12261 if (TREE_CODE (arg0) == MINUS_EXPR
12262 && TREE_CODE (TREE_OPERAND (arg0, 0)) == INTEGER_CST
12263 && operand_equal_p (TREE_OPERAND (arg0, 1), arg1, 0)
12264 && (TREE_INT_CST_LOW (TREE_OPERAND (arg0, 0)) & 1) == 1)
12266 return omit_two_operands (type,
12268 ? boolean_true_node : boolean_false_node,
12269 TREE_OPERAND (arg0, 1), arg1);
12272 /* If we have X - Y == 0, we can convert that to X == Y and similarly
12273 for !=. Don't do this for ordered comparisons due to overflow. */
12274 if (TREE_CODE (arg0) == MINUS_EXPR
12275 && integer_zerop (arg1))
12276 return fold_build2 (code, type,
12277 TREE_OPERAND (arg0, 0), TREE_OPERAND (arg0, 1));
12279 /* Convert ABS_EXPR<x> == 0 or ABS_EXPR<x> != 0 to x == 0 or x != 0. */
12280 if (TREE_CODE (arg0) == ABS_EXPR
12281 && (integer_zerop (arg1) || real_zerop (arg1)))
12282 return fold_build2 (code, type, TREE_OPERAND (arg0, 0), arg1);
12284 /* If this is an EQ or NE comparison with zero and ARG0 is
12285 (1 << foo) & bar, convert it to (bar >> foo) & 1. Both require
12286 two operations, but the latter can be done in one less insn
12287 on machines that have only two-operand insns or on which a
12288 constant cannot be the first operand. */
12289 if (TREE_CODE (arg0) == BIT_AND_EXPR
12290 && integer_zerop (arg1))
12292 tree arg00 = TREE_OPERAND (arg0, 0);
12293 tree arg01 = TREE_OPERAND (arg0, 1);
12294 if (TREE_CODE (arg00) == LSHIFT_EXPR
12295 && integer_onep (TREE_OPERAND (arg00, 0)))
12297 tree tem = fold_build2 (RSHIFT_EXPR, TREE_TYPE (arg00),
12298 arg01, TREE_OPERAND (arg00, 1));
12299 tem = fold_build2 (BIT_AND_EXPR, TREE_TYPE (arg0), tem,
12300 build_int_cst (TREE_TYPE (arg0), 1));
12301 return fold_build2 (code, type,
12302 fold_convert (TREE_TYPE (arg1), tem), arg1);
12304 else if (TREE_CODE (arg01) == LSHIFT_EXPR
12305 && integer_onep (TREE_OPERAND (arg01, 0)))
12307 tree tem = fold_build2 (RSHIFT_EXPR, TREE_TYPE (arg01),
12308 arg00, TREE_OPERAND (arg01, 1));
12309 tem = fold_build2 (BIT_AND_EXPR, TREE_TYPE (arg0), tem,
12310 build_int_cst (TREE_TYPE (arg0), 1));
12311 return fold_build2 (code, type,
12312 fold_convert (TREE_TYPE (arg1), tem), arg1);
12316 /* If this is an NE or EQ comparison of zero against the result of a
12317 signed MOD operation whose second operand is a power of 2, make
12318 the MOD operation unsigned since it is simpler and equivalent. */
12319 if (integer_zerop (arg1)
12320 && !TYPE_UNSIGNED (TREE_TYPE (arg0))
12321 && (TREE_CODE (arg0) == TRUNC_MOD_EXPR
12322 || TREE_CODE (arg0) == CEIL_MOD_EXPR
12323 || TREE_CODE (arg0) == FLOOR_MOD_EXPR
12324 || TREE_CODE (arg0) == ROUND_MOD_EXPR)
12325 && integer_pow2p (TREE_OPERAND (arg0, 1)))
12327 tree newtype = unsigned_type_for (TREE_TYPE (arg0));
12328 tree newmod = fold_build2 (TREE_CODE (arg0), newtype,
12329 fold_convert (newtype,
12330 TREE_OPERAND (arg0, 0)),
12331 fold_convert (newtype,
12332 TREE_OPERAND (arg0, 1)));
12334 return fold_build2 (code, type, newmod,
12335 fold_convert (newtype, arg1));
12338 /* Fold ((X >> C1) & C2) == 0 and ((X >> C1) & C2) != 0 where
12339 C1 is a valid shift constant, and C2 is a power of two, i.e.
12341 if (TREE_CODE (arg0) == BIT_AND_EXPR
12342 && TREE_CODE (TREE_OPERAND (arg0, 0)) == RSHIFT_EXPR
12343 && TREE_CODE (TREE_OPERAND (TREE_OPERAND (arg0, 0), 1))
12345 && integer_pow2p (TREE_OPERAND (arg0, 1))
12346 && integer_zerop (arg1))
12348 tree itype = TREE_TYPE (arg0);
12349 unsigned HOST_WIDE_INT prec = TYPE_PRECISION (itype);
12350 tree arg001 = TREE_OPERAND (TREE_OPERAND (arg0, 0), 1);
12352 /* Check for a valid shift count. */
12353 if (TREE_INT_CST_HIGH (arg001) == 0
12354 && TREE_INT_CST_LOW (arg001) < prec)
12356 tree arg01 = TREE_OPERAND (arg0, 1);
12357 tree arg000 = TREE_OPERAND (TREE_OPERAND (arg0, 0), 0);
12358 unsigned HOST_WIDE_INT log2 = tree_log2 (arg01);
12359 /* If (C2 << C1) doesn't overflow, then ((X >> C1) & C2) != 0
12360 can be rewritten as (X & (C2 << C1)) != 0. */
12361 if ((log2 + TREE_INT_CST_LOW (arg001)) < prec)
12363 tem = fold_build2 (LSHIFT_EXPR, itype, arg01, arg001);
12364 tem = fold_build2 (BIT_AND_EXPR, itype, arg000, tem);
12365 return fold_build2 (code, type, tem, arg1);
12367 /* Otherwise, for signed (arithmetic) shifts,
12368 ((X >> C1) & C2) != 0 is rewritten as X < 0, and
12369 ((X >> C1) & C2) == 0 is rewritten as X >= 0. */
12370 else if (!TYPE_UNSIGNED (itype))
12371 return fold_build2 (code == EQ_EXPR ? GE_EXPR : LT_EXPR, type,
12372 arg000, build_int_cst (itype, 0));
12373 /* Otherwise, of unsigned (logical) shifts,
12374 ((X >> C1) & C2) != 0 is rewritten as (X,false), and
12375 ((X >> C1) & C2) == 0 is rewritten as (X,true). */
12377 return omit_one_operand (type,
12378 code == EQ_EXPR ? integer_one_node
12379 : integer_zero_node,
12384 /* If this is an NE comparison of zero with an AND of one, remove the
12385 comparison since the AND will give the correct value. */
12386 if (code == NE_EXPR
12387 && integer_zerop (arg1)
12388 && TREE_CODE (arg0) == BIT_AND_EXPR
12389 && integer_onep (TREE_OPERAND (arg0, 1)))
12390 return fold_convert (type, arg0);
12392 /* If we have (A & C) == C where C is a power of 2, convert this into
12393 (A & C) != 0. Similarly for NE_EXPR. */
12394 if (TREE_CODE (arg0) == BIT_AND_EXPR
12395 && integer_pow2p (TREE_OPERAND (arg0, 1))
12396 && operand_equal_p (TREE_OPERAND (arg0, 1), arg1, 0))
12397 return fold_build2 (code == EQ_EXPR ? NE_EXPR : EQ_EXPR, type,
12398 arg0, fold_convert (TREE_TYPE (arg0),
12399 integer_zero_node));
12401 /* If we have (A & C) != 0 or (A & C) == 0 and C is the sign
12402 bit, then fold the expression into A < 0 or A >= 0. */
12403 tem = fold_single_bit_test_into_sign_test (code, arg0, arg1, type);
12407 /* If we have (A & C) == D where D & ~C != 0, convert this into 0.
12408 Similarly for NE_EXPR. */
12409 if (TREE_CODE (arg0) == BIT_AND_EXPR
12410 && TREE_CODE (arg1) == INTEGER_CST
12411 && TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST)
12413 tree notc = fold_build1 (BIT_NOT_EXPR,
12414 TREE_TYPE (TREE_OPERAND (arg0, 1)),
12415 TREE_OPERAND (arg0, 1));
12416 tree dandnotc = fold_build2 (BIT_AND_EXPR, TREE_TYPE (arg0),
12418 tree rslt = code == EQ_EXPR ? integer_zero_node : integer_one_node;
12419 if (integer_nonzerop (dandnotc))
12420 return omit_one_operand (type, rslt, arg0);
12423 /* If we have (A | C) == D where C & ~D != 0, convert this into 0.
12424 Similarly for NE_EXPR. */
12425 if (TREE_CODE (arg0) == BIT_IOR_EXPR
12426 && TREE_CODE (arg1) == INTEGER_CST
12427 && TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST)
12429 tree notd = fold_build1 (BIT_NOT_EXPR, TREE_TYPE (arg1), arg1);
12430 tree candnotd = fold_build2 (BIT_AND_EXPR, TREE_TYPE (arg0),
12431 TREE_OPERAND (arg0, 1), notd);
12432 tree rslt = code == EQ_EXPR ? integer_zero_node : integer_one_node;
12433 if (integer_nonzerop (candnotd))
12434 return omit_one_operand (type, rslt, arg0);
12437 /* If this is a comparison of a field, we may be able to simplify it. */
12438 if ((TREE_CODE (arg0) == COMPONENT_REF
12439 || TREE_CODE (arg0) == BIT_FIELD_REF)
12440 /* Handle the constant case even without -O
12441 to make sure the warnings are given. */
12442 && (optimize || TREE_CODE (arg1) == INTEGER_CST))
12444 t1 = optimize_bit_field_compare (code, type, arg0, arg1);
12449 /* Optimize comparisons of strlen vs zero to a compare of the
12450 first character of the string vs zero. To wit,
12451 strlen(ptr) == 0 => *ptr == 0
12452 strlen(ptr) != 0 => *ptr != 0
12453 Other cases should reduce to one of these two (or a constant)
12454 due to the return value of strlen being unsigned. */
12455 if (TREE_CODE (arg0) == CALL_EXPR
12456 && integer_zerop (arg1))
12458 tree fndecl = get_callee_fndecl (arg0);
12461 && DECL_BUILT_IN_CLASS (fndecl) == BUILT_IN_NORMAL
12462 && DECL_FUNCTION_CODE (fndecl) == BUILT_IN_STRLEN
12463 && call_expr_nargs (arg0) == 1
12464 && TREE_CODE (TREE_TYPE (CALL_EXPR_ARG (arg0, 0))) == POINTER_TYPE)
12466 tree iref = build_fold_indirect_ref (CALL_EXPR_ARG (arg0, 0));
12467 return fold_build2 (code, type, iref,
12468 build_int_cst (TREE_TYPE (iref), 0));
12472 /* Fold (X >> C) != 0 into X < 0 if C is one less than the width
12473 of X. Similarly fold (X >> C) == 0 into X >= 0. */
12474 if (TREE_CODE (arg0) == RSHIFT_EXPR
12475 && integer_zerop (arg1)
12476 && TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST)
12478 tree arg00 = TREE_OPERAND (arg0, 0);
12479 tree arg01 = TREE_OPERAND (arg0, 1);
12480 tree itype = TREE_TYPE (arg00);
12481 if (TREE_INT_CST_HIGH (arg01) == 0
12482 && TREE_INT_CST_LOW (arg01)
12483 == (unsigned HOST_WIDE_INT) (TYPE_PRECISION (itype) - 1))
12485 if (TYPE_UNSIGNED (itype))
12487 itype = signed_type_for (itype);
12488 arg00 = fold_convert (itype, arg00);
12490 return fold_build2 (code == EQ_EXPR ? GE_EXPR : LT_EXPR,
12491 type, arg00, build_int_cst (itype, 0));
12495 /* (X ^ Y) == 0 becomes X == Y, and (X ^ Y) != 0 becomes X != Y. */
12496 if (integer_zerop (arg1)
12497 && TREE_CODE (arg0) == BIT_XOR_EXPR)
12498 return fold_build2 (code, type, TREE_OPERAND (arg0, 0),
12499 TREE_OPERAND (arg0, 1));
12501 /* (X ^ Y) == Y becomes X == 0. We know that Y has no side-effects. */
12502 if (TREE_CODE (arg0) == BIT_XOR_EXPR
12503 && operand_equal_p (TREE_OPERAND (arg0, 1), arg1, 0))
12504 return fold_build2 (code, type, TREE_OPERAND (arg0, 0),
12505 build_int_cst (TREE_TYPE (arg1), 0));
12506 /* Likewise (X ^ Y) == X becomes Y == 0. X has no side-effects. */
12507 if (TREE_CODE (arg0) == BIT_XOR_EXPR
12508 && operand_equal_p (TREE_OPERAND (arg0, 0), arg1, 0)
12509 && reorder_operands_p (TREE_OPERAND (arg0, 1), arg1))
12510 return fold_build2 (code, type, TREE_OPERAND (arg0, 1),
12511 build_int_cst (TREE_TYPE (arg1), 0));
12513 /* (X ^ C1) op C2 can be rewritten as X op (C1 ^ C2). */
12514 if (TREE_CODE (arg0) == BIT_XOR_EXPR
12515 && TREE_CODE (arg1) == INTEGER_CST
12516 && TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST)
12517 return fold_build2 (code, type, TREE_OPERAND (arg0, 0),
12518 fold_build2 (BIT_XOR_EXPR, TREE_TYPE (arg1),
12519 TREE_OPERAND (arg0, 1), arg1));
12521 /* Fold (~X & C) == 0 into (X & C) != 0 and (~X & C) != 0 into
12522 (X & C) == 0 when C is a single bit. */
12523 if (TREE_CODE (arg0) == BIT_AND_EXPR
12524 && TREE_CODE (TREE_OPERAND (arg0, 0)) == BIT_NOT_EXPR
12525 && integer_zerop (arg1)
12526 && integer_pow2p (TREE_OPERAND (arg0, 1)))
12528 tem = fold_build2 (BIT_AND_EXPR, TREE_TYPE (arg0),
12529 TREE_OPERAND (TREE_OPERAND (arg0, 0), 0),
12530 TREE_OPERAND (arg0, 1));
12531 return fold_build2 (code == EQ_EXPR ? NE_EXPR : EQ_EXPR,
12535 /* Fold ((X & C) ^ C) eq/ne 0 into (X & C) ne/eq 0, when the
12536 constant C is a power of two, i.e. a single bit. */
12537 if (TREE_CODE (arg0) == BIT_XOR_EXPR
12538 && TREE_CODE (TREE_OPERAND (arg0, 0)) == BIT_AND_EXPR
12539 && integer_zerop (arg1)
12540 && integer_pow2p (TREE_OPERAND (arg0, 1))
12541 && operand_equal_p (TREE_OPERAND (TREE_OPERAND (arg0, 0), 1),
12542 TREE_OPERAND (arg0, 1), OEP_ONLY_CONST))
12544 tree arg00 = TREE_OPERAND (arg0, 0);
12545 return fold_build2 (code == EQ_EXPR ? NE_EXPR : EQ_EXPR, type,
12546 arg00, build_int_cst (TREE_TYPE (arg00), 0));
12549 /* Likewise, fold ((X ^ C) & C) eq/ne 0 into (X & C) ne/eq 0,
12550 when is C is a power of two, i.e. a single bit. */
12551 if (TREE_CODE (arg0) == BIT_AND_EXPR
12552 && TREE_CODE (TREE_OPERAND (arg0, 0)) == BIT_XOR_EXPR
12553 && integer_zerop (arg1)
12554 && integer_pow2p (TREE_OPERAND (arg0, 1))
12555 && operand_equal_p (TREE_OPERAND (TREE_OPERAND (arg0, 0), 1),
12556 TREE_OPERAND (arg0, 1), OEP_ONLY_CONST))
12558 tree arg000 = TREE_OPERAND (TREE_OPERAND (arg0, 0), 0);
12559 tem = fold_build2 (BIT_AND_EXPR, TREE_TYPE (arg000),
12560 arg000, TREE_OPERAND (arg0, 1));
12561 return fold_build2 (code == EQ_EXPR ? NE_EXPR : EQ_EXPR, type,
12562 tem, build_int_cst (TREE_TYPE (tem), 0));
12565 if (integer_zerop (arg1)
12566 && tree_expr_nonzero_p (arg0))
12568 tree res = constant_boolean_node (code==NE_EXPR, type);
12569 return omit_one_operand (type, res, arg0);
12572 /* Fold -X op -Y as X op Y, where op is eq/ne. */
12573 if (TREE_CODE (arg0) == NEGATE_EXPR
12574 && TREE_CODE (arg1) == NEGATE_EXPR)
12575 return fold_build2 (code, type,
12576 TREE_OPERAND (arg0, 0),
12577 TREE_OPERAND (arg1, 0));
12579 /* Fold (X & C) op (Y & C) as (X ^ Y) & C op 0", and symmetries. */
12580 if (TREE_CODE (arg0) == BIT_AND_EXPR
12581 && TREE_CODE (arg1) == BIT_AND_EXPR)
12583 tree arg00 = TREE_OPERAND (arg0, 0);
12584 tree arg01 = TREE_OPERAND (arg0, 1);
12585 tree arg10 = TREE_OPERAND (arg1, 0);
12586 tree arg11 = TREE_OPERAND (arg1, 1);
12587 tree itype = TREE_TYPE (arg0);
12589 if (operand_equal_p (arg01, 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 (arg01, 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));
12605 if (operand_equal_p (arg00, arg11, 0))
12606 return fold_build2 (code, type,
12607 fold_build2 (BIT_AND_EXPR, itype,
12608 fold_build2 (BIT_XOR_EXPR, itype,
12611 build_int_cst (itype, 0));
12613 if (operand_equal_p (arg00, arg10, 0))
12614 return fold_build2 (code, type,
12615 fold_build2 (BIT_AND_EXPR, itype,
12616 fold_build2 (BIT_XOR_EXPR, itype,
12619 build_int_cst (itype, 0));
12622 if (TREE_CODE (arg0) == BIT_XOR_EXPR
12623 && TREE_CODE (arg1) == BIT_XOR_EXPR)
12625 tree arg00 = TREE_OPERAND (arg0, 0);
12626 tree arg01 = TREE_OPERAND (arg0, 1);
12627 tree arg10 = TREE_OPERAND (arg1, 0);
12628 tree arg11 = TREE_OPERAND (arg1, 1);
12629 tree itype = TREE_TYPE (arg0);
12631 /* Optimize (X ^ Z) op (Y ^ Z) as X op Y, and symmetries.
12632 operand_equal_p guarantees no side-effects so we don't need
12633 to use omit_one_operand on Z. */
12634 if (operand_equal_p (arg01, arg11, 0))
12635 return fold_build2 (code, type, arg00, arg10);
12636 if (operand_equal_p (arg01, arg10, 0))
12637 return fold_build2 (code, type, arg00, arg11);
12638 if (operand_equal_p (arg00, arg11, 0))
12639 return fold_build2 (code, type, arg01, arg10);
12640 if (operand_equal_p (arg00, arg10, 0))
12641 return fold_build2 (code, type, arg01, arg11);
12643 /* Optimize (X ^ C1) op (Y ^ C2) as (X ^ (C1 ^ C2)) op Y. */
12644 if (TREE_CODE (arg01) == INTEGER_CST
12645 && TREE_CODE (arg11) == INTEGER_CST)
12646 return fold_build2 (code, type,
12647 fold_build2 (BIT_XOR_EXPR, itype, arg00,
12648 fold_build2 (BIT_XOR_EXPR, itype,
12653 /* Attempt to simplify equality/inequality comparisons of complex
12654 values. Only lower the comparison if the result is known or
12655 can be simplified to a single scalar comparison. */
12656 if ((TREE_CODE (arg0) == COMPLEX_EXPR
12657 || TREE_CODE (arg0) == COMPLEX_CST)
12658 && (TREE_CODE (arg1) == COMPLEX_EXPR
12659 || TREE_CODE (arg1) == COMPLEX_CST))
12661 tree real0, imag0, real1, imag1;
12664 if (TREE_CODE (arg0) == COMPLEX_EXPR)
12666 real0 = TREE_OPERAND (arg0, 0);
12667 imag0 = TREE_OPERAND (arg0, 1);
12671 real0 = TREE_REALPART (arg0);
12672 imag0 = TREE_IMAGPART (arg0);
12675 if (TREE_CODE (arg1) == COMPLEX_EXPR)
12677 real1 = TREE_OPERAND (arg1, 0);
12678 imag1 = TREE_OPERAND (arg1, 1);
12682 real1 = TREE_REALPART (arg1);
12683 imag1 = TREE_IMAGPART (arg1);
12686 rcond = fold_binary (code, type, real0, real1);
12687 if (rcond && TREE_CODE (rcond) == INTEGER_CST)
12689 if (integer_zerop (rcond))
12691 if (code == EQ_EXPR)
12692 return omit_two_operands (type, boolean_false_node,
12694 return fold_build2 (NE_EXPR, type, imag0, imag1);
12698 if (code == NE_EXPR)
12699 return omit_two_operands (type, boolean_true_node,
12701 return fold_build2 (EQ_EXPR, type, imag0, imag1);
12705 icond = fold_binary (code, type, imag0, imag1);
12706 if (icond && TREE_CODE (icond) == INTEGER_CST)
12708 if (integer_zerop (icond))
12710 if (code == EQ_EXPR)
12711 return omit_two_operands (type, boolean_false_node,
12713 return fold_build2 (NE_EXPR, type, real0, real1);
12717 if (code == NE_EXPR)
12718 return omit_two_operands (type, boolean_true_node,
12720 return fold_build2 (EQ_EXPR, type, real0, real1);
12731 tem = fold_comparison (code, type, op0, op1);
12732 if (tem != NULL_TREE)
12735 /* Transform comparisons of the form X +- C CMP X. */
12736 if ((TREE_CODE (arg0) == PLUS_EXPR || TREE_CODE (arg0) == MINUS_EXPR)
12737 && operand_equal_p (TREE_OPERAND (arg0, 0), arg1, 0)
12738 && ((TREE_CODE (TREE_OPERAND (arg0, 1)) == REAL_CST
12739 && !HONOR_SNANS (TYPE_MODE (TREE_TYPE (arg0))))
12740 || (TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST
12741 && TYPE_OVERFLOW_UNDEFINED (TREE_TYPE (arg1)))))
12743 tree arg01 = TREE_OPERAND (arg0, 1);
12744 enum tree_code code0 = TREE_CODE (arg0);
12747 if (TREE_CODE (arg01) == REAL_CST)
12748 is_positive = REAL_VALUE_NEGATIVE (TREE_REAL_CST (arg01)) ? -1 : 1;
12750 is_positive = tree_int_cst_sgn (arg01);
12752 /* (X - c) > X becomes false. */
12753 if (code == GT_EXPR
12754 && ((code0 == MINUS_EXPR && is_positive >= 0)
12755 || (code0 == PLUS_EXPR && is_positive <= 0)))
12757 if (TREE_CODE (arg01) == INTEGER_CST
12758 && TYPE_OVERFLOW_UNDEFINED (TREE_TYPE (arg1)))
12759 fold_overflow_warning (("assuming signed overflow does not "
12760 "occur when assuming that (X - c) > X "
12761 "is always false"),
12762 WARN_STRICT_OVERFLOW_ALL);
12763 return constant_boolean_node (0, type);
12766 /* Likewise (X + c) < X becomes false. */
12767 if (code == LT_EXPR
12768 && ((code0 == PLUS_EXPR && is_positive >= 0)
12769 || (code0 == MINUS_EXPR && is_positive <= 0)))
12771 if (TREE_CODE (arg01) == INTEGER_CST
12772 && TYPE_OVERFLOW_UNDEFINED (TREE_TYPE (arg1)))
12773 fold_overflow_warning (("assuming signed overflow does not "
12774 "occur when assuming that "
12775 "(X + c) < X is always false"),
12776 WARN_STRICT_OVERFLOW_ALL);
12777 return constant_boolean_node (0, type);
12780 /* Convert (X - c) <= X to true. */
12781 if (!HONOR_NANS (TYPE_MODE (TREE_TYPE (arg1)))
12783 && ((code0 == MINUS_EXPR && is_positive >= 0)
12784 || (code0 == PLUS_EXPR && is_positive <= 0)))
12786 if (TREE_CODE (arg01) == INTEGER_CST
12787 && TYPE_OVERFLOW_UNDEFINED (TREE_TYPE (arg1)))
12788 fold_overflow_warning (("assuming signed overflow does not "
12789 "occur when assuming that "
12790 "(X - c) <= X is always true"),
12791 WARN_STRICT_OVERFLOW_ALL);
12792 return constant_boolean_node (1, type);
12795 /* Convert (X + c) >= X to true. */
12796 if (!HONOR_NANS (TYPE_MODE (TREE_TYPE (arg1)))
12798 && ((code0 == PLUS_EXPR && is_positive >= 0)
12799 || (code0 == MINUS_EXPR && is_positive <= 0)))
12801 if (TREE_CODE (arg01) == INTEGER_CST
12802 && TYPE_OVERFLOW_UNDEFINED (TREE_TYPE (arg1)))
12803 fold_overflow_warning (("assuming signed overflow does not "
12804 "occur when assuming that "
12805 "(X + c) >= X is always true"),
12806 WARN_STRICT_OVERFLOW_ALL);
12807 return constant_boolean_node (1, type);
12810 if (TREE_CODE (arg01) == INTEGER_CST)
12812 /* Convert X + c > X and X - c < X to true for integers. */
12813 if (code == GT_EXPR
12814 && ((code0 == PLUS_EXPR && is_positive > 0)
12815 || (code0 == MINUS_EXPR && is_positive < 0)))
12817 if (TYPE_OVERFLOW_UNDEFINED (TREE_TYPE (arg1)))
12818 fold_overflow_warning (("assuming signed overflow does "
12819 "not occur when assuming that "
12820 "(X + c) > X is always true"),
12821 WARN_STRICT_OVERFLOW_ALL);
12822 return constant_boolean_node (1, type);
12825 if (code == LT_EXPR
12826 && ((code0 == MINUS_EXPR && is_positive > 0)
12827 || (code0 == PLUS_EXPR && is_positive < 0)))
12829 if (TYPE_OVERFLOW_UNDEFINED (TREE_TYPE (arg1)))
12830 fold_overflow_warning (("assuming signed overflow does "
12831 "not occur when assuming that "
12832 "(X - c) < X is always true"),
12833 WARN_STRICT_OVERFLOW_ALL);
12834 return constant_boolean_node (1, type);
12837 /* Convert X + c <= X and X - c >= X to false for integers. */
12838 if (code == LE_EXPR
12839 && ((code0 == PLUS_EXPR && is_positive > 0)
12840 || (code0 == MINUS_EXPR && is_positive < 0)))
12842 if (TYPE_OVERFLOW_UNDEFINED (TREE_TYPE (arg1)))
12843 fold_overflow_warning (("assuming signed overflow does "
12844 "not occur when assuming that "
12845 "(X + c) <= X is always false"),
12846 WARN_STRICT_OVERFLOW_ALL);
12847 return constant_boolean_node (0, type);
12850 if (code == GE_EXPR
12851 && ((code0 == MINUS_EXPR && is_positive > 0)
12852 || (code0 == PLUS_EXPR && is_positive < 0)))
12854 if (TYPE_OVERFLOW_UNDEFINED (TREE_TYPE (arg1)))
12855 fold_overflow_warning (("assuming signed overflow does "
12856 "not occur when assuming that "
12857 "(X - c) >= X is always false"),
12858 WARN_STRICT_OVERFLOW_ALL);
12859 return constant_boolean_node (0, type);
12864 /* Comparisons with the highest or lowest possible integer of
12865 the specified precision will have known values. */
12867 tree arg1_type = TREE_TYPE (arg1);
12868 unsigned int width = TYPE_PRECISION (arg1_type);
12870 if (TREE_CODE (arg1) == INTEGER_CST
12871 && width <= 2 * HOST_BITS_PER_WIDE_INT
12872 && (INTEGRAL_TYPE_P (arg1_type) || POINTER_TYPE_P (arg1_type)))
12874 HOST_WIDE_INT signed_max_hi;
12875 unsigned HOST_WIDE_INT signed_max_lo;
12876 unsigned HOST_WIDE_INT max_hi, max_lo, min_hi, min_lo;
12878 if (width <= HOST_BITS_PER_WIDE_INT)
12880 signed_max_lo = ((unsigned HOST_WIDE_INT) 1 << (width - 1))
12885 if (TYPE_UNSIGNED (arg1_type))
12887 max_lo = ((unsigned HOST_WIDE_INT) 2 << (width - 1)) - 1;
12893 max_lo = signed_max_lo;
12894 min_lo = ((unsigned HOST_WIDE_INT) -1 << (width - 1));
12900 width -= HOST_BITS_PER_WIDE_INT;
12901 signed_max_lo = -1;
12902 signed_max_hi = ((unsigned HOST_WIDE_INT) 1 << (width - 1))
12907 if (TYPE_UNSIGNED (arg1_type))
12909 max_hi = ((unsigned HOST_WIDE_INT) 2 << (width - 1)) - 1;
12914 max_hi = signed_max_hi;
12915 min_hi = ((unsigned HOST_WIDE_INT) -1 << (width - 1));
12919 if ((unsigned HOST_WIDE_INT) TREE_INT_CST_HIGH (arg1) == max_hi
12920 && TREE_INT_CST_LOW (arg1) == max_lo)
12924 return omit_one_operand (type, integer_zero_node, arg0);
12927 return fold_build2 (EQ_EXPR, type, op0, op1);
12930 return omit_one_operand (type, integer_one_node, arg0);
12933 return fold_build2 (NE_EXPR, type, op0, op1);
12935 /* The GE_EXPR and LT_EXPR cases above are not normally
12936 reached because of previous transformations. */
12941 else if ((unsigned HOST_WIDE_INT) TREE_INT_CST_HIGH (arg1)
12943 && TREE_INT_CST_LOW (arg1) == max_lo - 1)
12947 arg1 = const_binop (PLUS_EXPR, arg1,
12948 build_int_cst (TREE_TYPE (arg1), 1), 0);
12949 return fold_build2 (EQ_EXPR, type,
12950 fold_convert (TREE_TYPE (arg1), arg0),
12953 arg1 = const_binop (PLUS_EXPR, arg1,
12954 build_int_cst (TREE_TYPE (arg1), 1), 0);
12955 return fold_build2 (NE_EXPR, type,
12956 fold_convert (TREE_TYPE (arg1), arg0),
12961 else if ((unsigned HOST_WIDE_INT) TREE_INT_CST_HIGH (arg1)
12963 && TREE_INT_CST_LOW (arg1) == min_lo)
12967 return omit_one_operand (type, integer_zero_node, arg0);
12970 return fold_build2 (EQ_EXPR, type, op0, op1);
12973 return omit_one_operand (type, integer_one_node, arg0);
12976 return fold_build2 (NE_EXPR, type, op0, op1);
12981 else if ((unsigned HOST_WIDE_INT) TREE_INT_CST_HIGH (arg1)
12983 && TREE_INT_CST_LOW (arg1) == min_lo + 1)
12987 arg1 = const_binop (MINUS_EXPR, arg1, integer_one_node, 0);
12988 return fold_build2 (NE_EXPR, type,
12989 fold_convert (TREE_TYPE (arg1), arg0),
12992 arg1 = const_binop (MINUS_EXPR, arg1, integer_one_node, 0);
12993 return fold_build2 (EQ_EXPR, type,
12994 fold_convert (TREE_TYPE (arg1), arg0),
13000 else if (TREE_INT_CST_HIGH (arg1) == signed_max_hi
13001 && TREE_INT_CST_LOW (arg1) == signed_max_lo
13002 && TYPE_UNSIGNED (arg1_type)
13003 /* We will flip the signedness of the comparison operator
13004 associated with the mode of arg1, so the sign bit is
13005 specified by this mode. Check that arg1 is the signed
13006 max associated with this sign bit. */
13007 && width == GET_MODE_BITSIZE (TYPE_MODE (arg1_type))
13008 /* signed_type does not work on pointer types. */
13009 && INTEGRAL_TYPE_P (arg1_type))
13011 /* The following case also applies to X < signed_max+1
13012 and X >= signed_max+1 because previous transformations. */
13013 if (code == LE_EXPR || code == GT_EXPR)
13016 st = signed_type_for (TREE_TYPE (arg1));
13017 return fold_build2 (code == LE_EXPR ? GE_EXPR : LT_EXPR,
13018 type, fold_convert (st, arg0),
13019 build_int_cst (st, 0));
13025 /* If we are comparing an ABS_EXPR with a constant, we can
13026 convert all the cases into explicit comparisons, but they may
13027 well not be faster than doing the ABS and one comparison.
13028 But ABS (X) <= C is a range comparison, which becomes a subtraction
13029 and a comparison, and is probably faster. */
13030 if (code == LE_EXPR
13031 && TREE_CODE (arg1) == INTEGER_CST
13032 && TREE_CODE (arg0) == ABS_EXPR
13033 && ! TREE_SIDE_EFFECTS (arg0)
13034 && (0 != (tem = negate_expr (arg1)))
13035 && TREE_CODE (tem) == INTEGER_CST
13036 && !TREE_OVERFLOW (tem))
13037 return fold_build2 (TRUTH_ANDIF_EXPR, type,
13038 build2 (GE_EXPR, type,
13039 TREE_OPERAND (arg0, 0), tem),
13040 build2 (LE_EXPR, type,
13041 TREE_OPERAND (arg0, 0), arg1));
13043 /* Convert ABS_EXPR<x> >= 0 to true. */
13044 strict_overflow_p = false;
13045 if (code == GE_EXPR
13046 && (integer_zerop (arg1)
13047 || (! HONOR_NANS (TYPE_MODE (TREE_TYPE (arg0)))
13048 && real_zerop (arg1)))
13049 && tree_expr_nonnegative_warnv_p (arg0, &strict_overflow_p))
13051 if (strict_overflow_p)
13052 fold_overflow_warning (("assuming signed overflow does not occur "
13053 "when simplifying comparison of "
13054 "absolute value and zero"),
13055 WARN_STRICT_OVERFLOW_CONDITIONAL);
13056 return omit_one_operand (type, integer_one_node, arg0);
13059 /* Convert ABS_EXPR<x> < 0 to false. */
13060 strict_overflow_p = false;
13061 if (code == LT_EXPR
13062 && (integer_zerop (arg1) || real_zerop (arg1))
13063 && tree_expr_nonnegative_warnv_p (arg0, &strict_overflow_p))
13065 if (strict_overflow_p)
13066 fold_overflow_warning (("assuming signed overflow does not occur "
13067 "when simplifying comparison of "
13068 "absolute value and zero"),
13069 WARN_STRICT_OVERFLOW_CONDITIONAL);
13070 return omit_one_operand (type, integer_zero_node, arg0);
13073 /* If X is unsigned, convert X < (1 << Y) into X >> Y == 0
13074 and similarly for >= into !=. */
13075 if ((code == LT_EXPR || code == GE_EXPR)
13076 && TYPE_UNSIGNED (TREE_TYPE (arg0))
13077 && TREE_CODE (arg1) == LSHIFT_EXPR
13078 && integer_onep (TREE_OPERAND (arg1, 0)))
13079 return build2 (code == LT_EXPR ? EQ_EXPR : NE_EXPR, type,
13080 build2 (RSHIFT_EXPR, TREE_TYPE (arg0), arg0,
13081 TREE_OPERAND (arg1, 1)),
13082 build_int_cst (TREE_TYPE (arg0), 0));
13084 if ((code == LT_EXPR || code == GE_EXPR)
13085 && TYPE_UNSIGNED (TREE_TYPE (arg0))
13086 && CONVERT_EXPR_P (arg1)
13087 && TREE_CODE (TREE_OPERAND (arg1, 0)) == LSHIFT_EXPR
13088 && integer_onep (TREE_OPERAND (TREE_OPERAND (arg1, 0), 0)))
13090 build2 (code == LT_EXPR ? EQ_EXPR : NE_EXPR, type,
13091 fold_convert (TREE_TYPE (arg0),
13092 build2 (RSHIFT_EXPR, TREE_TYPE (arg0), arg0,
13093 TREE_OPERAND (TREE_OPERAND (arg1, 0),
13095 build_int_cst (TREE_TYPE (arg0), 0));
13099 case UNORDERED_EXPR:
13107 if (TREE_CODE (arg0) == REAL_CST && TREE_CODE (arg1) == REAL_CST)
13109 t1 = fold_relational_const (code, type, arg0, arg1);
13110 if (t1 != NULL_TREE)
13114 /* If the first operand is NaN, the result is constant. */
13115 if (TREE_CODE (arg0) == REAL_CST
13116 && REAL_VALUE_ISNAN (TREE_REAL_CST (arg0))
13117 && (code != LTGT_EXPR || ! flag_trapping_math))
13119 t1 = (code == ORDERED_EXPR || code == LTGT_EXPR)
13120 ? integer_zero_node
13121 : integer_one_node;
13122 return omit_one_operand (type, t1, arg1);
13125 /* If the second operand is NaN, the result is constant. */
13126 if (TREE_CODE (arg1) == REAL_CST
13127 && REAL_VALUE_ISNAN (TREE_REAL_CST (arg1))
13128 && (code != LTGT_EXPR || ! flag_trapping_math))
13130 t1 = (code == ORDERED_EXPR || code == LTGT_EXPR)
13131 ? integer_zero_node
13132 : integer_one_node;
13133 return omit_one_operand (type, t1, arg0);
13136 /* Simplify unordered comparison of something with itself. */
13137 if ((code == UNLE_EXPR || code == UNGE_EXPR || code == UNEQ_EXPR)
13138 && operand_equal_p (arg0, arg1, 0))
13139 return constant_boolean_node (1, type);
13141 if (code == LTGT_EXPR
13142 && !flag_trapping_math
13143 && operand_equal_p (arg0, arg1, 0))
13144 return constant_boolean_node (0, type);
13146 /* Fold (double)float1 CMP (double)float2 into float1 CMP float2. */
13148 tree targ0 = strip_float_extensions (arg0);
13149 tree targ1 = strip_float_extensions (arg1);
13150 tree newtype = TREE_TYPE (targ0);
13152 if (TYPE_PRECISION (TREE_TYPE (targ1)) > TYPE_PRECISION (newtype))
13153 newtype = TREE_TYPE (targ1);
13155 if (TYPE_PRECISION (newtype) < TYPE_PRECISION (TREE_TYPE (arg0)))
13156 return fold_build2 (code, type, fold_convert (newtype, targ0),
13157 fold_convert (newtype, targ1));
13162 case COMPOUND_EXPR:
13163 /* When pedantic, a compound expression can be neither an lvalue
13164 nor an integer constant expression. */
13165 if (TREE_SIDE_EFFECTS (arg0) || TREE_CONSTANT (arg1))
13167 /* Don't let (0, 0) be null pointer constant. */
13168 tem = integer_zerop (arg1) ? build1 (NOP_EXPR, type, arg1)
13169 : fold_convert (type, arg1);
13170 return pedantic_non_lvalue (tem);
13173 if ((TREE_CODE (arg0) == REAL_CST
13174 && TREE_CODE (arg1) == REAL_CST)
13175 || (TREE_CODE (arg0) == INTEGER_CST
13176 && TREE_CODE (arg1) == INTEGER_CST))
13177 return build_complex (type, arg0, arg1);
13181 /* An ASSERT_EXPR should never be passed to fold_binary. */
13182 gcc_unreachable ();
13186 } /* switch (code) */
13189 /* Callback for walk_tree, looking for LABEL_EXPR.
13190 Returns tree TP if it is LABEL_EXPR. Otherwise it returns NULL_TREE.
13191 Do not check the sub-tree of GOTO_EXPR. */
13194 contains_label_1 (tree *tp,
13195 int *walk_subtrees,
13196 void *data ATTRIBUTE_UNUSED)
13198 switch (TREE_CODE (*tp))
13203 *walk_subtrees = 0;
13210 /* Checks whether the sub-tree ST contains a label LABEL_EXPR which is
13211 accessible from outside the sub-tree. Returns NULL_TREE if no
13212 addressable label is found. */
13215 contains_label_p (tree st)
13217 return (walk_tree (&st, contains_label_1 , NULL, NULL) != NULL_TREE);
13220 /* Fold a ternary expression of code CODE and type TYPE with operands
13221 OP0, OP1, and OP2. Return the folded expression if folding is
13222 successful. Otherwise, return NULL_TREE. */
13225 fold_ternary (enum tree_code code, tree type, tree op0, tree op1, tree op2)
13228 tree arg0 = NULL_TREE, arg1 = NULL_TREE;
13229 enum tree_code_class kind = TREE_CODE_CLASS (code);
13231 gcc_assert (IS_EXPR_CODE_CLASS (kind)
13232 && TREE_CODE_LENGTH (code) == 3);
13234 /* Strip any conversions that don't change the mode. This is safe
13235 for every expression, except for a comparison expression because
13236 its signedness is derived from its operands. So, in the latter
13237 case, only strip conversions that don't change the signedness.
13239 Note that this is done as an internal manipulation within the
13240 constant folder, in order to find the simplest representation of
13241 the arguments so that their form can be studied. In any cases,
13242 the appropriate type conversions should be put back in the tree
13243 that will get out of the constant folder. */
13258 case COMPONENT_REF:
13259 if (TREE_CODE (arg0) == CONSTRUCTOR
13260 && ! type_contains_placeholder_p (TREE_TYPE (arg0)))
13262 unsigned HOST_WIDE_INT idx;
13264 FOR_EACH_CONSTRUCTOR_ELT (CONSTRUCTOR_ELTS (arg0), idx, field, value)
13271 /* Pedantic ANSI C says that a conditional expression is never an lvalue,
13272 so all simple results must be passed through pedantic_non_lvalue. */
13273 if (TREE_CODE (arg0) == INTEGER_CST)
13275 tree unused_op = integer_zerop (arg0) ? op1 : op2;
13276 tem = integer_zerop (arg0) ? op2 : op1;
13277 /* Only optimize constant conditions when the selected branch
13278 has the same type as the COND_EXPR. This avoids optimizing
13279 away "c ? x : throw", where the throw has a void type.
13280 Avoid throwing away that operand which contains label. */
13281 if ((!TREE_SIDE_EFFECTS (unused_op)
13282 || !contains_label_p (unused_op))
13283 && (! VOID_TYPE_P (TREE_TYPE (tem))
13284 || VOID_TYPE_P (type)))
13285 return pedantic_non_lvalue (tem);
13288 if (operand_equal_p (arg1, op2, 0))
13289 return pedantic_omit_one_operand (type, arg1, arg0);
13291 /* If we have A op B ? A : C, we may be able to convert this to a
13292 simpler expression, depending on the operation and the values
13293 of B and C. Signed zeros prevent all of these transformations,
13294 for reasons given above each one.
13296 Also try swapping the arguments and inverting the conditional. */
13297 if (COMPARISON_CLASS_P (arg0)
13298 && operand_equal_for_comparison_p (TREE_OPERAND (arg0, 0),
13299 arg1, TREE_OPERAND (arg0, 1))
13300 && !HONOR_SIGNED_ZEROS (TYPE_MODE (TREE_TYPE (arg1))))
13302 tem = fold_cond_expr_with_comparison (type, arg0, op1, op2);
13307 if (COMPARISON_CLASS_P (arg0)
13308 && operand_equal_for_comparison_p (TREE_OPERAND (arg0, 0),
13310 TREE_OPERAND (arg0, 1))
13311 && !HONOR_SIGNED_ZEROS (TYPE_MODE (TREE_TYPE (op2))))
13313 tem = fold_truth_not_expr (arg0);
13314 if (tem && COMPARISON_CLASS_P (tem))
13316 tem = fold_cond_expr_with_comparison (type, tem, op2, op1);
13322 /* If the second operand is simpler than the third, swap them
13323 since that produces better jump optimization results. */
13324 if (truth_value_p (TREE_CODE (arg0))
13325 && tree_swap_operands_p (op1, op2, false))
13327 /* See if this can be inverted. If it can't, possibly because
13328 it was a floating-point inequality comparison, don't do
13330 tem = fold_truth_not_expr (arg0);
13332 return fold_build3 (code, type, tem, op2, op1);
13335 /* Convert A ? 1 : 0 to simply A. */
13336 if (integer_onep (op1)
13337 && integer_zerop (op2)
13338 /* If we try to convert OP0 to our type, the
13339 call to fold will try to move the conversion inside
13340 a COND, which will recurse. In that case, the COND_EXPR
13341 is probably the best choice, so leave it alone. */
13342 && type == TREE_TYPE (arg0))
13343 return pedantic_non_lvalue (arg0);
13345 /* Convert A ? 0 : 1 to !A. This prefers the use of NOT_EXPR
13346 over COND_EXPR in cases such as floating point comparisons. */
13347 if (integer_zerop (op1)
13348 && integer_onep (op2)
13349 && truth_value_p (TREE_CODE (arg0)))
13350 return pedantic_non_lvalue (fold_convert (type,
13351 invert_truthvalue (arg0)));
13353 /* A < 0 ? <sign bit of A> : 0 is simply (A & <sign bit of A>). */
13354 if (TREE_CODE (arg0) == LT_EXPR
13355 && integer_zerop (TREE_OPERAND (arg0, 1))
13356 && integer_zerop (op2)
13357 && (tem = sign_bit_p (TREE_OPERAND (arg0, 0), arg1)))
13359 /* sign_bit_p only checks ARG1 bits within A's precision.
13360 If <sign bit of A> has wider type than A, bits outside
13361 of A's precision in <sign bit of A> need to be checked.
13362 If they are all 0, this optimization needs to be done
13363 in unsigned A's type, if they are all 1 in signed A's type,
13364 otherwise this can't be done. */
13365 if (TYPE_PRECISION (TREE_TYPE (tem))
13366 < TYPE_PRECISION (TREE_TYPE (arg1))
13367 && TYPE_PRECISION (TREE_TYPE (tem))
13368 < TYPE_PRECISION (type))
13370 unsigned HOST_WIDE_INT mask_lo;
13371 HOST_WIDE_INT mask_hi;
13372 int inner_width, outer_width;
13375 inner_width = TYPE_PRECISION (TREE_TYPE (tem));
13376 outer_width = TYPE_PRECISION (TREE_TYPE (arg1));
13377 if (outer_width > TYPE_PRECISION (type))
13378 outer_width = TYPE_PRECISION (type);
13380 if (outer_width > HOST_BITS_PER_WIDE_INT)
13382 mask_hi = ((unsigned HOST_WIDE_INT) -1
13383 >> (2 * HOST_BITS_PER_WIDE_INT - outer_width));
13389 mask_lo = ((unsigned HOST_WIDE_INT) -1
13390 >> (HOST_BITS_PER_WIDE_INT - outer_width));
13392 if (inner_width > HOST_BITS_PER_WIDE_INT)
13394 mask_hi &= ~((unsigned HOST_WIDE_INT) -1
13395 >> (HOST_BITS_PER_WIDE_INT - inner_width));
13399 mask_lo &= ~((unsigned HOST_WIDE_INT) -1
13400 >> (HOST_BITS_PER_WIDE_INT - inner_width));
13402 if ((TREE_INT_CST_HIGH (arg1) & mask_hi) == mask_hi
13403 && (TREE_INT_CST_LOW (arg1) & mask_lo) == mask_lo)
13405 tem_type = signed_type_for (TREE_TYPE (tem));
13406 tem = fold_convert (tem_type, tem);
13408 else if ((TREE_INT_CST_HIGH (arg1) & mask_hi) == 0
13409 && (TREE_INT_CST_LOW (arg1) & mask_lo) == 0)
13411 tem_type = unsigned_type_for (TREE_TYPE (tem));
13412 tem = fold_convert (tem_type, tem);
13419 return fold_convert (type,
13420 fold_build2 (BIT_AND_EXPR,
13421 TREE_TYPE (tem), tem,
13422 fold_convert (TREE_TYPE (tem),
13426 /* (A >> N) & 1 ? (1 << N) : 0 is simply A & (1 << N). A & 1 was
13427 already handled above. */
13428 if (TREE_CODE (arg0) == BIT_AND_EXPR
13429 && integer_onep (TREE_OPERAND (arg0, 1))
13430 && integer_zerop (op2)
13431 && integer_pow2p (arg1))
13433 tree tem = TREE_OPERAND (arg0, 0);
13435 if (TREE_CODE (tem) == RSHIFT_EXPR
13436 && TREE_CODE (TREE_OPERAND (tem, 1)) == INTEGER_CST
13437 && (unsigned HOST_WIDE_INT) tree_log2 (arg1) ==
13438 TREE_INT_CST_LOW (TREE_OPERAND (tem, 1)))
13439 return fold_build2 (BIT_AND_EXPR, type,
13440 TREE_OPERAND (tem, 0), arg1);
13443 /* A & N ? N : 0 is simply A & N if N is a power of two. This
13444 is probably obsolete because the first operand should be a
13445 truth value (that's why we have the two cases above), but let's
13446 leave it in until we can confirm this for all front-ends. */
13447 if (integer_zerop (op2)
13448 && TREE_CODE (arg0) == NE_EXPR
13449 && integer_zerop (TREE_OPERAND (arg0, 1))
13450 && integer_pow2p (arg1)
13451 && TREE_CODE (TREE_OPERAND (arg0, 0)) == BIT_AND_EXPR
13452 && operand_equal_p (TREE_OPERAND (TREE_OPERAND (arg0, 0), 1),
13453 arg1, OEP_ONLY_CONST))
13454 return pedantic_non_lvalue (fold_convert (type,
13455 TREE_OPERAND (arg0, 0)));
13457 /* Convert A ? B : 0 into A && B if A and B are truth values. */
13458 if (integer_zerop (op2)
13459 && truth_value_p (TREE_CODE (arg0))
13460 && truth_value_p (TREE_CODE (arg1)))
13461 return fold_build2 (TRUTH_ANDIF_EXPR, type,
13462 fold_convert (type, arg0),
13465 /* Convert A ? B : 1 into !A || B if A and B are truth values. */
13466 if (integer_onep (op2)
13467 && truth_value_p (TREE_CODE (arg0))
13468 && truth_value_p (TREE_CODE (arg1)))
13470 /* Only perform transformation if ARG0 is easily inverted. */
13471 tem = fold_truth_not_expr (arg0);
13473 return fold_build2 (TRUTH_ORIF_EXPR, type,
13474 fold_convert (type, tem),
13478 /* Convert A ? 0 : B into !A && B if A and B are truth values. */
13479 if (integer_zerop (arg1)
13480 && truth_value_p (TREE_CODE (arg0))
13481 && truth_value_p (TREE_CODE (op2)))
13483 /* Only perform transformation if ARG0 is easily inverted. */
13484 tem = fold_truth_not_expr (arg0);
13486 return fold_build2 (TRUTH_ANDIF_EXPR, type,
13487 fold_convert (type, tem),
13491 /* Convert A ? 1 : B into A || B if A and B are truth values. */
13492 if (integer_onep (arg1)
13493 && truth_value_p (TREE_CODE (arg0))
13494 && truth_value_p (TREE_CODE (op2)))
13495 return fold_build2 (TRUTH_ORIF_EXPR, type,
13496 fold_convert (type, arg0),
13502 /* CALL_EXPRs used to be ternary exprs. Catch any mistaken uses
13503 of fold_ternary on them. */
13504 gcc_unreachable ();
13506 case BIT_FIELD_REF:
13507 if ((TREE_CODE (arg0) == VECTOR_CST
13508 || (TREE_CODE (arg0) == CONSTRUCTOR && TREE_CONSTANT (arg0)))
13509 && type == TREE_TYPE (TREE_TYPE (arg0)))
13511 unsigned HOST_WIDE_INT width = tree_low_cst (arg1, 1);
13512 unsigned HOST_WIDE_INT idx = tree_low_cst (op2, 1);
13515 && simple_cst_equal (arg1, TYPE_SIZE (type)) == 1
13516 && (idx % width) == 0
13517 && (idx = idx / width)
13518 < TYPE_VECTOR_SUBPARTS (TREE_TYPE (arg0)))
13520 tree elements = NULL_TREE;
13522 if (TREE_CODE (arg0) == VECTOR_CST)
13523 elements = TREE_VECTOR_CST_ELTS (arg0);
13526 unsigned HOST_WIDE_INT idx;
13529 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (arg0), idx, value)
13530 elements = tree_cons (NULL_TREE, value, elements);
13532 while (idx-- > 0 && elements)
13533 elements = TREE_CHAIN (elements);
13535 return TREE_VALUE (elements);
13537 return fold_convert (type, integer_zero_node);
13541 /* A bit-field-ref that referenced the full argument can be stripped. */
13542 if (INTEGRAL_TYPE_P (TREE_TYPE (arg0))
13543 && TYPE_PRECISION (TREE_TYPE (arg0)) == tree_low_cst (arg1, 1)
13544 && integer_zerop (op2))
13545 return fold_convert (type, arg0);
13551 } /* switch (code) */
13554 /* Perform constant folding and related simplification of EXPR.
13555 The related simplifications include x*1 => x, x*0 => 0, etc.,
13556 and application of the associative law.
13557 NOP_EXPR conversions may be removed freely (as long as we
13558 are careful not to change the type of the overall expression).
13559 We cannot simplify through a CONVERT_EXPR, FIX_EXPR or FLOAT_EXPR,
13560 but we can constant-fold them if they have constant operands. */
13562 #ifdef ENABLE_FOLD_CHECKING
13563 # define fold(x) fold_1 (x)
13564 static tree fold_1 (tree);
13570 const tree t = expr;
13571 enum tree_code code = TREE_CODE (t);
13572 enum tree_code_class kind = TREE_CODE_CLASS (code);
13575 /* Return right away if a constant. */
13576 if (kind == tcc_constant)
13579 /* CALL_EXPR-like objects with variable numbers of operands are
13580 treated specially. */
13581 if (kind == tcc_vl_exp)
13583 if (code == CALL_EXPR)
13585 tem = fold_call_expr (expr, false);
13586 return tem ? tem : expr;
13591 if (IS_EXPR_CODE_CLASS (kind))
13593 tree type = TREE_TYPE (t);
13594 tree op0, op1, op2;
13596 switch (TREE_CODE_LENGTH (code))
13599 op0 = TREE_OPERAND (t, 0);
13600 tem = fold_unary (code, type, op0);
13601 return tem ? tem : expr;
13603 op0 = TREE_OPERAND (t, 0);
13604 op1 = TREE_OPERAND (t, 1);
13605 tem = fold_binary (code, type, op0, op1);
13606 return tem ? tem : expr;
13608 op0 = TREE_OPERAND (t, 0);
13609 op1 = TREE_OPERAND (t, 1);
13610 op2 = TREE_OPERAND (t, 2);
13611 tem = fold_ternary (code, type, op0, op1, op2);
13612 return tem ? tem : expr;
13622 tree op0 = TREE_OPERAND (t, 0);
13623 tree op1 = TREE_OPERAND (t, 1);
13625 if (TREE_CODE (op1) == INTEGER_CST
13626 && TREE_CODE (op0) == CONSTRUCTOR
13627 && ! type_contains_placeholder_p (TREE_TYPE (op0)))
13629 VEC(constructor_elt,gc) *elts = CONSTRUCTOR_ELTS (op0);
13630 unsigned HOST_WIDE_INT end = VEC_length (constructor_elt, elts);
13631 unsigned HOST_WIDE_INT begin = 0;
13633 /* Find a matching index by means of a binary search. */
13634 while (begin != end)
13636 unsigned HOST_WIDE_INT middle = (begin + end) / 2;
13637 tree index = VEC_index (constructor_elt, elts, middle)->index;
13639 if (TREE_CODE (index) == INTEGER_CST
13640 && tree_int_cst_lt (index, op1))
13641 begin = middle + 1;
13642 else if (TREE_CODE (index) == INTEGER_CST
13643 && tree_int_cst_lt (op1, index))
13645 else if (TREE_CODE (index) == RANGE_EXPR
13646 && tree_int_cst_lt (TREE_OPERAND (index, 1), op1))
13647 begin = middle + 1;
13648 else if (TREE_CODE (index) == RANGE_EXPR
13649 && tree_int_cst_lt (op1, TREE_OPERAND (index, 0)))
13652 return VEC_index (constructor_elt, elts, middle)->value;
13660 return fold (DECL_INITIAL (t));
13664 } /* switch (code) */
13667 #ifdef ENABLE_FOLD_CHECKING
13670 static void fold_checksum_tree (const_tree, struct md5_ctx *, htab_t);
13671 static void fold_check_failed (const_tree, const_tree);
13672 void print_fold_checksum (const_tree);
13674 /* When --enable-checking=fold, compute a digest of expr before
13675 and after actual fold call to see if fold did not accidentally
13676 change original expr. */
13682 struct md5_ctx ctx;
13683 unsigned char checksum_before[16], checksum_after[16];
13686 ht = htab_create (32, htab_hash_pointer, htab_eq_pointer, NULL);
13687 md5_init_ctx (&ctx);
13688 fold_checksum_tree (expr, &ctx, ht);
13689 md5_finish_ctx (&ctx, checksum_before);
13692 ret = fold_1 (expr);
13694 md5_init_ctx (&ctx);
13695 fold_checksum_tree (expr, &ctx, ht);
13696 md5_finish_ctx (&ctx, checksum_after);
13699 if (memcmp (checksum_before, checksum_after, 16))
13700 fold_check_failed (expr, ret);
13706 print_fold_checksum (const_tree expr)
13708 struct md5_ctx ctx;
13709 unsigned char checksum[16], cnt;
13712 ht = htab_create (32, htab_hash_pointer, htab_eq_pointer, NULL);
13713 md5_init_ctx (&ctx);
13714 fold_checksum_tree (expr, &ctx, ht);
13715 md5_finish_ctx (&ctx, checksum);
13717 for (cnt = 0; cnt < 16; ++cnt)
13718 fprintf (stderr, "%02x", checksum[cnt]);
13719 putc ('\n', stderr);
13723 fold_check_failed (const_tree expr ATTRIBUTE_UNUSED, const_tree ret ATTRIBUTE_UNUSED)
13725 internal_error ("fold check: original tree changed by fold");
13729 fold_checksum_tree (const_tree expr, struct md5_ctx *ctx, htab_t ht)
13732 enum tree_code code;
13733 union tree_node buf;
13738 gcc_assert ((sizeof (struct tree_exp) + 5 * sizeof (tree)
13739 <= sizeof (struct tree_function_decl))
13740 && sizeof (struct tree_type) <= sizeof (struct tree_function_decl));
13743 slot = (const void **) htab_find_slot (ht, expr, INSERT);
13747 code = TREE_CODE (expr);
13748 if (TREE_CODE_CLASS (code) == tcc_declaration
13749 && DECL_ASSEMBLER_NAME_SET_P (expr))
13751 /* Allow DECL_ASSEMBLER_NAME to be modified. */
13752 memcpy ((char *) &buf, expr, tree_size (expr));
13753 SET_DECL_ASSEMBLER_NAME ((tree)&buf, NULL);
13754 expr = (tree) &buf;
13756 else if (TREE_CODE_CLASS (code) == tcc_type
13757 && (TYPE_POINTER_TO (expr)
13758 || TYPE_REFERENCE_TO (expr)
13759 || TYPE_CACHED_VALUES_P (expr)
13760 || TYPE_CONTAINS_PLACEHOLDER_INTERNAL (expr)
13761 || TYPE_NEXT_VARIANT (expr)))
13763 /* Allow these fields to be modified. */
13765 memcpy ((char *) &buf, expr, tree_size (expr));
13766 expr = tmp = (tree) &buf;
13767 TYPE_CONTAINS_PLACEHOLDER_INTERNAL (tmp) = 0;
13768 TYPE_POINTER_TO (tmp) = NULL;
13769 TYPE_REFERENCE_TO (tmp) = NULL;
13770 TYPE_NEXT_VARIANT (tmp) = NULL;
13771 if (TYPE_CACHED_VALUES_P (tmp))
13773 TYPE_CACHED_VALUES_P (tmp) = 0;
13774 TYPE_CACHED_VALUES (tmp) = NULL;
13777 md5_process_bytes (expr, tree_size (expr), ctx);
13778 fold_checksum_tree (TREE_TYPE (expr), ctx, ht);
13779 if (TREE_CODE_CLASS (code) != tcc_type
13780 && TREE_CODE_CLASS (code) != tcc_declaration
13781 && code != TREE_LIST
13782 && code != SSA_NAME)
13783 fold_checksum_tree (TREE_CHAIN (expr), ctx, ht);
13784 switch (TREE_CODE_CLASS (code))
13790 md5_process_bytes (TREE_STRING_POINTER (expr),
13791 TREE_STRING_LENGTH (expr), ctx);
13794 fold_checksum_tree (TREE_REALPART (expr), ctx, ht);
13795 fold_checksum_tree (TREE_IMAGPART (expr), ctx, ht);
13798 fold_checksum_tree (TREE_VECTOR_CST_ELTS (expr), ctx, ht);
13804 case tcc_exceptional:
13808 fold_checksum_tree (TREE_PURPOSE (expr), ctx, ht);
13809 fold_checksum_tree (TREE_VALUE (expr), ctx, ht);
13810 expr = TREE_CHAIN (expr);
13811 goto recursive_label;
13814 for (i = 0; i < TREE_VEC_LENGTH (expr); ++i)
13815 fold_checksum_tree (TREE_VEC_ELT (expr, i), ctx, ht);
13821 case tcc_expression:
13822 case tcc_reference:
13823 case tcc_comparison:
13826 case tcc_statement:
13828 len = TREE_OPERAND_LENGTH (expr);
13829 for (i = 0; i < len; ++i)
13830 fold_checksum_tree (TREE_OPERAND (expr, i), ctx, ht);
13832 case tcc_declaration:
13833 fold_checksum_tree (DECL_NAME (expr), ctx, ht);
13834 fold_checksum_tree (DECL_CONTEXT (expr), ctx, ht);
13835 if (CODE_CONTAINS_STRUCT (TREE_CODE (expr), TS_DECL_COMMON))
13837 fold_checksum_tree (DECL_SIZE (expr), ctx, ht);
13838 fold_checksum_tree (DECL_SIZE_UNIT (expr), ctx, ht);
13839 fold_checksum_tree (DECL_INITIAL (expr), ctx, ht);
13840 fold_checksum_tree (DECL_ABSTRACT_ORIGIN (expr), ctx, ht);
13841 fold_checksum_tree (DECL_ATTRIBUTES (expr), ctx, ht);
13843 if (CODE_CONTAINS_STRUCT (TREE_CODE (expr), TS_DECL_WITH_VIS))
13844 fold_checksum_tree (DECL_SECTION_NAME (expr), ctx, ht);
13846 if (CODE_CONTAINS_STRUCT (TREE_CODE (expr), TS_DECL_NON_COMMON))
13848 fold_checksum_tree (DECL_VINDEX (expr), ctx, ht);
13849 fold_checksum_tree (DECL_RESULT_FLD (expr), ctx, ht);
13850 fold_checksum_tree (DECL_ARGUMENT_FLD (expr), ctx, ht);
13854 if (TREE_CODE (expr) == ENUMERAL_TYPE)
13855 fold_checksum_tree (TYPE_VALUES (expr), ctx, ht);
13856 fold_checksum_tree (TYPE_SIZE (expr), ctx, ht);
13857 fold_checksum_tree (TYPE_SIZE_UNIT (expr), ctx, ht);
13858 fold_checksum_tree (TYPE_ATTRIBUTES (expr), ctx, ht);
13859 fold_checksum_tree (TYPE_NAME (expr), ctx, ht);
13860 if (INTEGRAL_TYPE_P (expr)
13861 || SCALAR_FLOAT_TYPE_P (expr))
13863 fold_checksum_tree (TYPE_MIN_VALUE (expr), ctx, ht);
13864 fold_checksum_tree (TYPE_MAX_VALUE (expr), ctx, ht);
13866 fold_checksum_tree (TYPE_MAIN_VARIANT (expr), ctx, ht);
13867 if (TREE_CODE (expr) == RECORD_TYPE
13868 || TREE_CODE (expr) == UNION_TYPE
13869 || TREE_CODE (expr) == QUAL_UNION_TYPE)
13870 fold_checksum_tree (TYPE_BINFO (expr), ctx, ht);
13871 fold_checksum_tree (TYPE_CONTEXT (expr), ctx, ht);
13878 /* Helper function for outputting the checksum of a tree T. When
13879 debugging with gdb, you can "define mynext" to be "next" followed
13880 by "call debug_fold_checksum (op0)", then just trace down till the
13884 debug_fold_checksum (const_tree t)
13887 unsigned char checksum[16];
13888 struct md5_ctx ctx;
13889 htab_t ht = htab_create (32, htab_hash_pointer, htab_eq_pointer, NULL);
13891 md5_init_ctx (&ctx);
13892 fold_checksum_tree (t, &ctx, ht);
13893 md5_finish_ctx (&ctx, checksum);
13896 for (i = 0; i < 16; i++)
13897 fprintf (stderr, "%d ", checksum[i]);
13899 fprintf (stderr, "\n");
13904 /* Fold a unary tree expression with code CODE of type TYPE with an
13905 operand OP0. Return a folded expression if successful. Otherwise,
13906 return a tree expression with code CODE of type TYPE with an
13910 fold_build1_stat (enum tree_code code, tree type, tree op0 MEM_STAT_DECL)
13913 #ifdef ENABLE_FOLD_CHECKING
13914 unsigned char checksum_before[16], checksum_after[16];
13915 struct md5_ctx ctx;
13918 ht = htab_create (32, htab_hash_pointer, htab_eq_pointer, NULL);
13919 md5_init_ctx (&ctx);
13920 fold_checksum_tree (op0, &ctx, ht);
13921 md5_finish_ctx (&ctx, checksum_before);
13925 tem = fold_unary (code, type, op0);
13927 tem = build1_stat (code, type, op0 PASS_MEM_STAT);
13929 #ifdef ENABLE_FOLD_CHECKING
13930 md5_init_ctx (&ctx);
13931 fold_checksum_tree (op0, &ctx, ht);
13932 md5_finish_ctx (&ctx, checksum_after);
13935 if (memcmp (checksum_before, checksum_after, 16))
13936 fold_check_failed (op0, tem);
13941 /* Fold a binary tree expression with code CODE of type TYPE with
13942 operands OP0 and OP1. Return a folded expression if successful.
13943 Otherwise, return a tree expression with code CODE of type TYPE
13944 with operands OP0 and OP1. */
13947 fold_build2_stat (enum tree_code code, tree type, tree op0, tree op1
13951 #ifdef ENABLE_FOLD_CHECKING
13952 unsigned char checksum_before_op0[16],
13953 checksum_before_op1[16],
13954 checksum_after_op0[16],
13955 checksum_after_op1[16];
13956 struct md5_ctx ctx;
13959 ht = htab_create (32, htab_hash_pointer, htab_eq_pointer, NULL);
13960 md5_init_ctx (&ctx);
13961 fold_checksum_tree (op0, &ctx, ht);
13962 md5_finish_ctx (&ctx, checksum_before_op0);
13965 md5_init_ctx (&ctx);
13966 fold_checksum_tree (op1, &ctx, ht);
13967 md5_finish_ctx (&ctx, checksum_before_op1);
13971 tem = fold_binary (code, type, op0, op1);
13973 tem = build2_stat (code, type, op0, op1 PASS_MEM_STAT);
13975 #ifdef ENABLE_FOLD_CHECKING
13976 md5_init_ctx (&ctx);
13977 fold_checksum_tree (op0, &ctx, ht);
13978 md5_finish_ctx (&ctx, checksum_after_op0);
13981 if (memcmp (checksum_before_op0, checksum_after_op0, 16))
13982 fold_check_failed (op0, tem);
13984 md5_init_ctx (&ctx);
13985 fold_checksum_tree (op1, &ctx, ht);
13986 md5_finish_ctx (&ctx, checksum_after_op1);
13989 if (memcmp (checksum_before_op1, checksum_after_op1, 16))
13990 fold_check_failed (op1, tem);
13995 /* Fold a ternary tree expression with code CODE of type TYPE with
13996 operands OP0, OP1, and OP2. Return a folded expression if
13997 successful. Otherwise, return a tree expression with code CODE of
13998 type TYPE with operands OP0, OP1, and OP2. */
14001 fold_build3_stat (enum tree_code code, tree type, tree op0, tree op1, tree op2
14005 #ifdef ENABLE_FOLD_CHECKING
14006 unsigned char checksum_before_op0[16],
14007 checksum_before_op1[16],
14008 checksum_before_op2[16],
14009 checksum_after_op0[16],
14010 checksum_after_op1[16],
14011 checksum_after_op2[16];
14012 struct md5_ctx ctx;
14015 ht = htab_create (32, htab_hash_pointer, htab_eq_pointer, NULL);
14016 md5_init_ctx (&ctx);
14017 fold_checksum_tree (op0, &ctx, ht);
14018 md5_finish_ctx (&ctx, checksum_before_op0);
14021 md5_init_ctx (&ctx);
14022 fold_checksum_tree (op1, &ctx, ht);
14023 md5_finish_ctx (&ctx, checksum_before_op1);
14026 md5_init_ctx (&ctx);
14027 fold_checksum_tree (op2, &ctx, ht);
14028 md5_finish_ctx (&ctx, checksum_before_op2);
14032 gcc_assert (TREE_CODE_CLASS (code) != tcc_vl_exp);
14033 tem = fold_ternary (code, type, op0, op1, op2);
14035 tem = build3_stat (code, type, op0, op1, op2 PASS_MEM_STAT);
14037 #ifdef ENABLE_FOLD_CHECKING
14038 md5_init_ctx (&ctx);
14039 fold_checksum_tree (op0, &ctx, ht);
14040 md5_finish_ctx (&ctx, checksum_after_op0);
14043 if (memcmp (checksum_before_op0, checksum_after_op0, 16))
14044 fold_check_failed (op0, tem);
14046 md5_init_ctx (&ctx);
14047 fold_checksum_tree (op1, &ctx, ht);
14048 md5_finish_ctx (&ctx, checksum_after_op1);
14051 if (memcmp (checksum_before_op1, checksum_after_op1, 16))
14052 fold_check_failed (op1, tem);
14054 md5_init_ctx (&ctx);
14055 fold_checksum_tree (op2, &ctx, ht);
14056 md5_finish_ctx (&ctx, checksum_after_op2);
14059 if (memcmp (checksum_before_op2, checksum_after_op2, 16))
14060 fold_check_failed (op2, tem);
14065 /* Fold a CALL_EXPR expression of type TYPE with operands FN and NARGS
14066 arguments in ARGARRAY, and a null static chain.
14067 Return a folded expression if successful. Otherwise, return a CALL_EXPR
14068 of type TYPE from the given operands as constructed by build_call_array. */
14071 fold_build_call_array (tree type, tree fn, int nargs, tree *argarray)
14074 #ifdef ENABLE_FOLD_CHECKING
14075 unsigned char checksum_before_fn[16],
14076 checksum_before_arglist[16],
14077 checksum_after_fn[16],
14078 checksum_after_arglist[16];
14079 struct md5_ctx ctx;
14083 ht = htab_create (32, htab_hash_pointer, htab_eq_pointer, NULL);
14084 md5_init_ctx (&ctx);
14085 fold_checksum_tree (fn, &ctx, ht);
14086 md5_finish_ctx (&ctx, checksum_before_fn);
14089 md5_init_ctx (&ctx);
14090 for (i = 0; i < nargs; i++)
14091 fold_checksum_tree (argarray[i], &ctx, ht);
14092 md5_finish_ctx (&ctx, checksum_before_arglist);
14096 tem = fold_builtin_call_array (type, fn, nargs, argarray);
14098 #ifdef ENABLE_FOLD_CHECKING
14099 md5_init_ctx (&ctx);
14100 fold_checksum_tree (fn, &ctx, ht);
14101 md5_finish_ctx (&ctx, checksum_after_fn);
14104 if (memcmp (checksum_before_fn, checksum_after_fn, 16))
14105 fold_check_failed (fn, tem);
14107 md5_init_ctx (&ctx);
14108 for (i = 0; i < nargs; i++)
14109 fold_checksum_tree (argarray[i], &ctx, ht);
14110 md5_finish_ctx (&ctx, checksum_after_arglist);
14113 if (memcmp (checksum_before_arglist, checksum_after_arglist, 16))
14114 fold_check_failed (NULL_TREE, tem);
14119 /* Perform constant folding and related simplification of initializer
14120 expression EXPR. These behave identically to "fold_buildN" but ignore
14121 potential run-time traps and exceptions that fold must preserve. */
14123 #define START_FOLD_INIT \
14124 int saved_signaling_nans = flag_signaling_nans;\
14125 int saved_trapping_math = flag_trapping_math;\
14126 int saved_rounding_math = flag_rounding_math;\
14127 int saved_trapv = flag_trapv;\
14128 int saved_folding_initializer = folding_initializer;\
14129 flag_signaling_nans = 0;\
14130 flag_trapping_math = 0;\
14131 flag_rounding_math = 0;\
14133 folding_initializer = 1;
14135 #define END_FOLD_INIT \
14136 flag_signaling_nans = saved_signaling_nans;\
14137 flag_trapping_math = saved_trapping_math;\
14138 flag_rounding_math = saved_rounding_math;\
14139 flag_trapv = saved_trapv;\
14140 folding_initializer = saved_folding_initializer;
14143 fold_build1_initializer (enum tree_code code, tree type, tree op)
14148 result = fold_build1 (code, type, op);
14155 fold_build2_initializer (enum tree_code code, tree type, tree op0, tree op1)
14160 result = fold_build2 (code, type, op0, op1);
14167 fold_build3_initializer (enum tree_code code, tree type, tree op0, tree op1,
14173 result = fold_build3 (code, type, op0, op1, op2);
14180 fold_build_call_array_initializer (tree type, tree fn,
14181 int nargs, tree *argarray)
14186 result = fold_build_call_array (type, fn, nargs, argarray);
14192 #undef START_FOLD_INIT
14193 #undef END_FOLD_INIT
14195 /* Determine if first argument is a multiple of second argument. Return 0 if
14196 it is not, or we cannot easily determined it to be.
14198 An example of the sort of thing we care about (at this point; this routine
14199 could surely be made more general, and expanded to do what the *_DIV_EXPR's
14200 fold cases do now) is discovering that
14202 SAVE_EXPR (I) * SAVE_EXPR (J * 8)
14208 when we know that the two SAVE_EXPR (J * 8) nodes are the same node.
14210 This code also handles discovering that
14212 SAVE_EXPR (I) * SAVE_EXPR (J * 8)
14214 is a multiple of 8 so we don't have to worry about dealing with a
14215 possible remainder.
14217 Note that we *look* inside a SAVE_EXPR only to determine how it was
14218 calculated; it is not safe for fold to do much of anything else with the
14219 internals of a SAVE_EXPR, since it cannot know when it will be evaluated
14220 at run time. For example, the latter example above *cannot* be implemented
14221 as SAVE_EXPR (I) * J or any variant thereof, since the value of J at
14222 evaluation time of the original SAVE_EXPR is not necessarily the same at
14223 the time the new expression is evaluated. The only optimization of this
14224 sort that would be valid is changing
14226 SAVE_EXPR (I) * SAVE_EXPR (SAVE_EXPR (J) * 8)
14230 SAVE_EXPR (I) * SAVE_EXPR (J)
14232 (where the same SAVE_EXPR (J) is used in the original and the
14233 transformed version). */
14236 multiple_of_p (tree type, const_tree top, const_tree bottom)
14238 if (operand_equal_p (top, bottom, 0))
14241 if (TREE_CODE (type) != INTEGER_TYPE)
14244 switch (TREE_CODE (top))
14247 /* Bitwise and provides a power of two multiple. If the mask is
14248 a multiple of BOTTOM then TOP is a multiple of BOTTOM. */
14249 if (!integer_pow2p (bottom))
14254 return (multiple_of_p (type, TREE_OPERAND (top, 0), bottom)
14255 || multiple_of_p (type, TREE_OPERAND (top, 1), bottom));
14259 return (multiple_of_p (type, TREE_OPERAND (top, 0), bottom)
14260 && multiple_of_p (type, TREE_OPERAND (top, 1), bottom));
14263 if (TREE_CODE (TREE_OPERAND (top, 1)) == INTEGER_CST)
14267 op1 = TREE_OPERAND (top, 1);
14268 /* const_binop may not detect overflow correctly,
14269 so check for it explicitly here. */
14270 if (TYPE_PRECISION (TREE_TYPE (size_one_node))
14271 > TREE_INT_CST_LOW (op1)
14272 && TREE_INT_CST_HIGH (op1) == 0
14273 && 0 != (t1 = fold_convert (type,
14274 const_binop (LSHIFT_EXPR,
14277 && !TREE_OVERFLOW (t1))
14278 return multiple_of_p (type, t1, bottom);
14283 /* Can't handle conversions from non-integral or wider integral type. */
14284 if ((TREE_CODE (TREE_TYPE (TREE_OPERAND (top, 0))) != INTEGER_TYPE)
14285 || (TYPE_PRECISION (type)
14286 < TYPE_PRECISION (TREE_TYPE (TREE_OPERAND (top, 0)))))
14289 /* .. fall through ... */
14292 return multiple_of_p (type, TREE_OPERAND (top, 0), bottom);
14295 if (TREE_CODE (bottom) != INTEGER_CST
14296 || integer_zerop (bottom)
14297 || (TYPE_UNSIGNED (type)
14298 && (tree_int_cst_sgn (top) < 0
14299 || tree_int_cst_sgn (bottom) < 0)))
14301 return integer_zerop (int_const_binop (TRUNC_MOD_EXPR,
14309 /* Return true if CODE or TYPE is known to be non-negative. */
14312 tree_simple_nonnegative_warnv_p (enum tree_code code, tree type)
14314 if ((TYPE_PRECISION (type) != 1 || TYPE_UNSIGNED (type))
14315 && truth_value_p (code))
14316 /* Truth values evaluate to 0 or 1, which is nonnegative unless we
14317 have a signed:1 type (where the value is -1 and 0). */
14322 /* Return true if (CODE OP0) is known to be non-negative. If the return
14323 value is based on the assumption that signed overflow is undefined,
14324 set *STRICT_OVERFLOW_P to true; otherwise, don't change
14325 *STRICT_OVERFLOW_P. */
14328 tree_unary_nonnegative_warnv_p (enum tree_code code, tree type, tree op0,
14329 bool *strict_overflow_p)
14331 if (TYPE_UNSIGNED (type))
14337 /* We can't return 1 if flag_wrapv is set because
14338 ABS_EXPR<INT_MIN> = INT_MIN. */
14339 if (!INTEGRAL_TYPE_P (type))
14341 if (TYPE_OVERFLOW_UNDEFINED (type))
14343 *strict_overflow_p = true;
14348 case NON_LVALUE_EXPR:
14350 case FIX_TRUNC_EXPR:
14351 return tree_expr_nonnegative_warnv_p (op0,
14352 strict_overflow_p);
14356 tree inner_type = TREE_TYPE (op0);
14357 tree outer_type = type;
14359 if (TREE_CODE (outer_type) == REAL_TYPE)
14361 if (TREE_CODE (inner_type) == REAL_TYPE)
14362 return tree_expr_nonnegative_warnv_p (op0,
14363 strict_overflow_p);
14364 if (TREE_CODE (inner_type) == INTEGER_TYPE)
14366 if (TYPE_UNSIGNED (inner_type))
14368 return tree_expr_nonnegative_warnv_p (op0,
14369 strict_overflow_p);
14372 else if (TREE_CODE (outer_type) == INTEGER_TYPE)
14374 if (TREE_CODE (inner_type) == REAL_TYPE)
14375 return tree_expr_nonnegative_warnv_p (op0,
14376 strict_overflow_p);
14377 if (TREE_CODE (inner_type) == INTEGER_TYPE)
14378 return TYPE_PRECISION (inner_type) < TYPE_PRECISION (outer_type)
14379 && TYPE_UNSIGNED (inner_type);
14385 return tree_simple_nonnegative_warnv_p (code, type);
14388 /* We don't know sign of `t', so be conservative and return false. */
14392 /* Return true if (CODE OP0 OP1) is known to be non-negative. If the return
14393 value is based on the assumption that signed overflow is undefined,
14394 set *STRICT_OVERFLOW_P to true; otherwise, don't change
14395 *STRICT_OVERFLOW_P. */
14398 tree_binary_nonnegative_warnv_p (enum tree_code code, tree type, tree op0,
14399 tree op1, bool *strict_overflow_p)
14401 if (TYPE_UNSIGNED (type))
14406 case POINTER_PLUS_EXPR:
14408 if (FLOAT_TYPE_P (type))
14409 return (tree_expr_nonnegative_warnv_p (op0,
14411 && tree_expr_nonnegative_warnv_p (op1,
14412 strict_overflow_p));
14414 /* zero_extend(x) + zero_extend(y) is non-negative if x and y are
14415 both unsigned and at least 2 bits shorter than the result. */
14416 if (TREE_CODE (type) == INTEGER_TYPE
14417 && TREE_CODE (op0) == NOP_EXPR
14418 && TREE_CODE (op1) == NOP_EXPR)
14420 tree inner1 = TREE_TYPE (TREE_OPERAND (op0, 0));
14421 tree inner2 = TREE_TYPE (TREE_OPERAND (op1, 0));
14422 if (TREE_CODE (inner1) == INTEGER_TYPE && TYPE_UNSIGNED (inner1)
14423 && TREE_CODE (inner2) == INTEGER_TYPE && TYPE_UNSIGNED (inner2))
14425 unsigned int prec = MAX (TYPE_PRECISION (inner1),
14426 TYPE_PRECISION (inner2)) + 1;
14427 return prec < TYPE_PRECISION (type);
14433 if (FLOAT_TYPE_P (type))
14435 /* x * x for floating point x is always non-negative. */
14436 if (operand_equal_p (op0, op1, 0))
14438 return (tree_expr_nonnegative_warnv_p (op0,
14440 && tree_expr_nonnegative_warnv_p (op1,
14441 strict_overflow_p));
14444 /* zero_extend(x) * zero_extend(y) is non-negative if x and y are
14445 both unsigned and their total bits is shorter than the result. */
14446 if (TREE_CODE (type) == INTEGER_TYPE
14447 && (TREE_CODE (op0) == NOP_EXPR || TREE_CODE (op0) == INTEGER_CST)
14448 && (TREE_CODE (op1) == NOP_EXPR || TREE_CODE (op1) == INTEGER_CST))
14450 tree inner0 = (TREE_CODE (op0) == NOP_EXPR)
14451 ? TREE_TYPE (TREE_OPERAND (op0, 0))
14453 tree inner1 = (TREE_CODE (op1) == NOP_EXPR)
14454 ? TREE_TYPE (TREE_OPERAND (op1, 0))
14457 bool unsigned0 = TYPE_UNSIGNED (inner0);
14458 bool unsigned1 = TYPE_UNSIGNED (inner1);
14460 if (TREE_CODE (op0) == INTEGER_CST)
14461 unsigned0 = unsigned0 || tree_int_cst_sgn (op0) >= 0;
14463 if (TREE_CODE (op1) == INTEGER_CST)
14464 unsigned1 = unsigned1 || tree_int_cst_sgn (op1) >= 0;
14466 if (TREE_CODE (inner0) == INTEGER_TYPE && unsigned0
14467 && TREE_CODE (inner1) == INTEGER_TYPE && unsigned1)
14469 unsigned int precision0 = (TREE_CODE (op0) == INTEGER_CST)
14470 ? tree_int_cst_min_precision (op0, /*unsignedp=*/true)
14471 : TYPE_PRECISION (inner0);
14473 unsigned int precision1 = (TREE_CODE (op1) == INTEGER_CST)
14474 ? tree_int_cst_min_precision (op1, /*unsignedp=*/true)
14475 : TYPE_PRECISION (inner1);
14477 return precision0 + precision1 < TYPE_PRECISION (type);
14484 return (tree_expr_nonnegative_warnv_p (op0,
14486 || tree_expr_nonnegative_warnv_p (op1,
14487 strict_overflow_p));
14493 case TRUNC_DIV_EXPR:
14494 case CEIL_DIV_EXPR:
14495 case FLOOR_DIV_EXPR:
14496 case ROUND_DIV_EXPR:
14497 return (tree_expr_nonnegative_warnv_p (op0,
14499 && tree_expr_nonnegative_warnv_p (op1,
14500 strict_overflow_p));
14502 case TRUNC_MOD_EXPR:
14503 case CEIL_MOD_EXPR:
14504 case FLOOR_MOD_EXPR:
14505 case ROUND_MOD_EXPR:
14506 return tree_expr_nonnegative_warnv_p (op0,
14507 strict_overflow_p);
14509 return tree_simple_nonnegative_warnv_p (code, type);
14512 /* We don't know sign of `t', so be conservative and return false. */
14516 /* Return true if T is known to be non-negative. If the return
14517 value is based on the assumption that signed overflow is undefined,
14518 set *STRICT_OVERFLOW_P to true; otherwise, don't change
14519 *STRICT_OVERFLOW_P. */
14522 tree_single_nonnegative_warnv_p (tree t, bool *strict_overflow_p)
14524 if (TYPE_UNSIGNED (TREE_TYPE (t)))
14527 switch (TREE_CODE (t))
14530 return tree_int_cst_sgn (t) >= 0;
14533 return ! REAL_VALUE_NEGATIVE (TREE_REAL_CST (t));
14536 return ! FIXED_VALUE_NEGATIVE (TREE_FIXED_CST (t));
14539 return (tree_expr_nonnegative_warnv_p (TREE_OPERAND (t, 1),
14541 && tree_expr_nonnegative_warnv_p (TREE_OPERAND (t, 2),
14542 strict_overflow_p));
14544 return tree_simple_nonnegative_warnv_p (TREE_CODE (t),
14547 /* We don't know sign of `t', so be conservative and return false. */
14551 /* Return true if T is known to be non-negative. If the return
14552 value is based on the assumption that signed overflow is undefined,
14553 set *STRICT_OVERFLOW_P to true; otherwise, don't change
14554 *STRICT_OVERFLOW_P. */
14557 tree_call_nonnegative_warnv_p (tree type, tree fndecl,
14558 tree arg0, tree arg1, bool *strict_overflow_p)
14560 if (fndecl && DECL_BUILT_IN_CLASS (fndecl) == BUILT_IN_NORMAL)
14561 switch (DECL_FUNCTION_CODE (fndecl))
14563 CASE_FLT_FN (BUILT_IN_ACOS):
14564 CASE_FLT_FN (BUILT_IN_ACOSH):
14565 CASE_FLT_FN (BUILT_IN_CABS):
14566 CASE_FLT_FN (BUILT_IN_COSH):
14567 CASE_FLT_FN (BUILT_IN_ERFC):
14568 CASE_FLT_FN (BUILT_IN_EXP):
14569 CASE_FLT_FN (BUILT_IN_EXP10):
14570 CASE_FLT_FN (BUILT_IN_EXP2):
14571 CASE_FLT_FN (BUILT_IN_FABS):
14572 CASE_FLT_FN (BUILT_IN_FDIM):
14573 CASE_FLT_FN (BUILT_IN_HYPOT):
14574 CASE_FLT_FN (BUILT_IN_POW10):
14575 CASE_INT_FN (BUILT_IN_FFS):
14576 CASE_INT_FN (BUILT_IN_PARITY):
14577 CASE_INT_FN (BUILT_IN_POPCOUNT):
14578 case BUILT_IN_BSWAP32:
14579 case BUILT_IN_BSWAP64:
14583 CASE_FLT_FN (BUILT_IN_SQRT):
14584 /* sqrt(-0.0) is -0.0. */
14585 if (!HONOR_SIGNED_ZEROS (TYPE_MODE (type)))
14587 return tree_expr_nonnegative_warnv_p (arg0,
14588 strict_overflow_p);
14590 CASE_FLT_FN (BUILT_IN_ASINH):
14591 CASE_FLT_FN (BUILT_IN_ATAN):
14592 CASE_FLT_FN (BUILT_IN_ATANH):
14593 CASE_FLT_FN (BUILT_IN_CBRT):
14594 CASE_FLT_FN (BUILT_IN_CEIL):
14595 CASE_FLT_FN (BUILT_IN_ERF):
14596 CASE_FLT_FN (BUILT_IN_EXPM1):
14597 CASE_FLT_FN (BUILT_IN_FLOOR):
14598 CASE_FLT_FN (BUILT_IN_FMOD):
14599 CASE_FLT_FN (BUILT_IN_FREXP):
14600 CASE_FLT_FN (BUILT_IN_LCEIL):
14601 CASE_FLT_FN (BUILT_IN_LDEXP):
14602 CASE_FLT_FN (BUILT_IN_LFLOOR):
14603 CASE_FLT_FN (BUILT_IN_LLCEIL):
14604 CASE_FLT_FN (BUILT_IN_LLFLOOR):
14605 CASE_FLT_FN (BUILT_IN_LLRINT):
14606 CASE_FLT_FN (BUILT_IN_LLROUND):
14607 CASE_FLT_FN (BUILT_IN_LRINT):
14608 CASE_FLT_FN (BUILT_IN_LROUND):
14609 CASE_FLT_FN (BUILT_IN_MODF):
14610 CASE_FLT_FN (BUILT_IN_NEARBYINT):
14611 CASE_FLT_FN (BUILT_IN_RINT):
14612 CASE_FLT_FN (BUILT_IN_ROUND):
14613 CASE_FLT_FN (BUILT_IN_SCALB):
14614 CASE_FLT_FN (BUILT_IN_SCALBLN):
14615 CASE_FLT_FN (BUILT_IN_SCALBN):
14616 CASE_FLT_FN (BUILT_IN_SIGNBIT):
14617 CASE_FLT_FN (BUILT_IN_SIGNIFICAND):
14618 CASE_FLT_FN (BUILT_IN_SINH):
14619 CASE_FLT_FN (BUILT_IN_TANH):
14620 CASE_FLT_FN (BUILT_IN_TRUNC):
14621 /* True if the 1st argument is nonnegative. */
14622 return tree_expr_nonnegative_warnv_p (arg0,
14623 strict_overflow_p);
14625 CASE_FLT_FN (BUILT_IN_FMAX):
14626 /* True if the 1st OR 2nd arguments are nonnegative. */
14627 return (tree_expr_nonnegative_warnv_p (arg0,
14629 || (tree_expr_nonnegative_warnv_p (arg1,
14630 strict_overflow_p)));
14632 CASE_FLT_FN (BUILT_IN_FMIN):
14633 /* True if the 1st AND 2nd arguments are nonnegative. */
14634 return (tree_expr_nonnegative_warnv_p (arg0,
14636 && (tree_expr_nonnegative_warnv_p (arg1,
14637 strict_overflow_p)));
14639 CASE_FLT_FN (BUILT_IN_COPYSIGN):
14640 /* True if the 2nd argument is nonnegative. */
14641 return tree_expr_nonnegative_warnv_p (arg1,
14642 strict_overflow_p);
14644 CASE_FLT_FN (BUILT_IN_POWI):
14645 /* True if the 1st argument is nonnegative or the second
14646 argument is an even integer. */
14647 if (TREE_CODE (arg1) == INTEGER_CST
14648 && (TREE_INT_CST_LOW (arg1) & 1) == 0)
14650 return tree_expr_nonnegative_warnv_p (arg0,
14651 strict_overflow_p);
14653 CASE_FLT_FN (BUILT_IN_POW):
14654 /* True if the 1st argument is nonnegative or the second
14655 argument is an even integer valued real. */
14656 if (TREE_CODE (arg1) == REAL_CST)
14661 c = TREE_REAL_CST (arg1);
14662 n = real_to_integer (&c);
14665 REAL_VALUE_TYPE cint;
14666 real_from_integer (&cint, VOIDmode, n,
14667 n < 0 ? -1 : 0, 0);
14668 if (real_identical (&c, &cint))
14672 return tree_expr_nonnegative_warnv_p (arg0,
14673 strict_overflow_p);
14678 return tree_simple_nonnegative_warnv_p (CALL_EXPR,
14682 /* Return true if T is known to be non-negative. If the return
14683 value is based on the assumption that signed overflow is undefined,
14684 set *STRICT_OVERFLOW_P to true; otherwise, don't change
14685 *STRICT_OVERFLOW_P. */
14688 tree_invalid_nonnegative_warnv_p (tree t, bool *strict_overflow_p)
14690 enum tree_code code = TREE_CODE (t);
14691 if (TYPE_UNSIGNED (TREE_TYPE (t)))
14698 tree temp = TARGET_EXPR_SLOT (t);
14699 t = TARGET_EXPR_INITIAL (t);
14701 /* If the initializer is non-void, then it's a normal expression
14702 that will be assigned to the slot. */
14703 if (!VOID_TYPE_P (t))
14704 return tree_expr_nonnegative_warnv_p (t, strict_overflow_p);
14706 /* Otherwise, the initializer sets the slot in some way. One common
14707 way is an assignment statement at the end of the initializer. */
14710 if (TREE_CODE (t) == BIND_EXPR)
14711 t = expr_last (BIND_EXPR_BODY (t));
14712 else if (TREE_CODE (t) == TRY_FINALLY_EXPR
14713 || TREE_CODE (t) == TRY_CATCH_EXPR)
14714 t = expr_last (TREE_OPERAND (t, 0));
14715 else if (TREE_CODE (t) == STATEMENT_LIST)
14720 if (TREE_CODE (t) == MODIFY_EXPR
14721 && TREE_OPERAND (t, 0) == temp)
14722 return tree_expr_nonnegative_warnv_p (TREE_OPERAND (t, 1),
14723 strict_overflow_p);
14730 tree arg0 = call_expr_nargs (t) > 0 ? CALL_EXPR_ARG (t, 0) : NULL_TREE;
14731 tree arg1 = call_expr_nargs (t) > 1 ? CALL_EXPR_ARG (t, 1) : NULL_TREE;
14733 return tree_call_nonnegative_warnv_p (TREE_TYPE (t),
14734 get_callee_fndecl (t),
14737 strict_overflow_p);
14739 case COMPOUND_EXPR:
14741 return tree_expr_nonnegative_warnv_p (TREE_OPERAND (t, 1),
14742 strict_overflow_p);
14744 return tree_expr_nonnegative_warnv_p (expr_last (TREE_OPERAND (t, 1)),
14745 strict_overflow_p);
14747 return tree_expr_nonnegative_warnv_p (TREE_OPERAND (t, 0),
14748 strict_overflow_p);
14751 return tree_simple_nonnegative_warnv_p (TREE_CODE (t),
14755 /* We don't know sign of `t', so be conservative and return false. */
14759 /* Return true if T is known to be non-negative. If the return
14760 value is based on the assumption that signed overflow is undefined,
14761 set *STRICT_OVERFLOW_P to true; otherwise, don't change
14762 *STRICT_OVERFLOW_P. */
14765 tree_expr_nonnegative_warnv_p (tree t, bool *strict_overflow_p)
14767 enum tree_code code;
14768 if (t == error_mark_node)
14771 code = TREE_CODE (t);
14772 switch (TREE_CODE_CLASS (code))
14775 case tcc_comparison:
14776 return tree_binary_nonnegative_warnv_p (TREE_CODE (t),
14778 TREE_OPERAND (t, 0),
14779 TREE_OPERAND (t, 1),
14780 strict_overflow_p);
14783 return tree_unary_nonnegative_warnv_p (TREE_CODE (t),
14785 TREE_OPERAND (t, 0),
14786 strict_overflow_p);
14789 case tcc_declaration:
14790 case tcc_reference:
14791 return tree_single_nonnegative_warnv_p (t, strict_overflow_p);
14799 case TRUTH_AND_EXPR:
14800 case TRUTH_OR_EXPR:
14801 case TRUTH_XOR_EXPR:
14802 return tree_binary_nonnegative_warnv_p (TREE_CODE (t),
14804 TREE_OPERAND (t, 0),
14805 TREE_OPERAND (t, 1),
14806 strict_overflow_p);
14807 case TRUTH_NOT_EXPR:
14808 return tree_unary_nonnegative_warnv_p (TREE_CODE (t),
14810 TREE_OPERAND (t, 0),
14811 strict_overflow_p);
14818 case WITH_SIZE_EXPR:
14822 return tree_single_nonnegative_warnv_p (t, strict_overflow_p);
14825 return tree_invalid_nonnegative_warnv_p (t, strict_overflow_p);
14829 /* Return true if `t' is known to be non-negative. Handle warnings
14830 about undefined signed overflow. */
14833 tree_expr_nonnegative_p (tree t)
14835 bool ret, strict_overflow_p;
14837 strict_overflow_p = false;
14838 ret = tree_expr_nonnegative_warnv_p (t, &strict_overflow_p);
14839 if (strict_overflow_p)
14840 fold_overflow_warning (("assuming signed overflow does not occur when "
14841 "determining that expression is always "
14843 WARN_STRICT_OVERFLOW_MISC);
14848 /* Return true when (CODE OP0) is an address and is known to be nonzero.
14849 For floating point we further ensure that T is not denormal.
14850 Similar logic is present in nonzero_address in rtlanal.h.
14852 If the return value is based on the assumption that signed overflow
14853 is undefined, set *STRICT_OVERFLOW_P to true; otherwise, don't
14854 change *STRICT_OVERFLOW_P. */
14857 tree_unary_nonzero_warnv_p (enum tree_code code, tree type, tree op0,
14858 bool *strict_overflow_p)
14863 return tree_expr_nonzero_warnv_p (op0,
14864 strict_overflow_p);
14868 tree inner_type = TREE_TYPE (op0);
14869 tree outer_type = type;
14871 return (TYPE_PRECISION (outer_type) >= TYPE_PRECISION (inner_type)
14872 && tree_expr_nonzero_warnv_p (op0,
14873 strict_overflow_p));
14877 case NON_LVALUE_EXPR:
14878 return tree_expr_nonzero_warnv_p (op0,
14879 strict_overflow_p);
14888 /* Return true when (CODE OP0 OP1) is an address and is known to be nonzero.
14889 For floating point we further ensure that T is not denormal.
14890 Similar logic is present in nonzero_address in rtlanal.h.
14892 If the return value is based on the assumption that signed overflow
14893 is undefined, set *STRICT_OVERFLOW_P to true; otherwise, don't
14894 change *STRICT_OVERFLOW_P. */
14897 tree_binary_nonzero_warnv_p (enum tree_code code,
14900 tree op1, bool *strict_overflow_p)
14902 bool sub_strict_overflow_p;
14905 case POINTER_PLUS_EXPR:
14907 if (TYPE_OVERFLOW_UNDEFINED (type))
14909 /* With the presence of negative values it is hard
14910 to say something. */
14911 sub_strict_overflow_p = false;
14912 if (!tree_expr_nonnegative_warnv_p (op0,
14913 &sub_strict_overflow_p)
14914 || !tree_expr_nonnegative_warnv_p (op1,
14915 &sub_strict_overflow_p))
14917 /* One of operands must be positive and the other non-negative. */
14918 /* We don't set *STRICT_OVERFLOW_P here: even if this value
14919 overflows, on a twos-complement machine the sum of two
14920 nonnegative numbers can never be zero. */
14921 return (tree_expr_nonzero_warnv_p (op0,
14923 || tree_expr_nonzero_warnv_p (op1,
14924 strict_overflow_p));
14929 if (TYPE_OVERFLOW_UNDEFINED (type))
14931 if (tree_expr_nonzero_warnv_p (op0,
14933 && tree_expr_nonzero_warnv_p (op1,
14934 strict_overflow_p))
14936 *strict_overflow_p = true;
14943 sub_strict_overflow_p = false;
14944 if (tree_expr_nonzero_warnv_p (op0,
14945 &sub_strict_overflow_p)
14946 && tree_expr_nonzero_warnv_p (op1,
14947 &sub_strict_overflow_p))
14949 if (sub_strict_overflow_p)
14950 *strict_overflow_p = true;
14955 sub_strict_overflow_p = false;
14956 if (tree_expr_nonzero_warnv_p (op0,
14957 &sub_strict_overflow_p))
14959 if (sub_strict_overflow_p)
14960 *strict_overflow_p = true;
14962 /* When both operands are nonzero, then MAX must be too. */
14963 if (tree_expr_nonzero_warnv_p (op1,
14964 strict_overflow_p))
14967 /* MAX where operand 0 is positive is positive. */
14968 return tree_expr_nonnegative_warnv_p (op0,
14969 strict_overflow_p);
14971 /* MAX where operand 1 is positive is positive. */
14972 else if (tree_expr_nonzero_warnv_p (op1,
14973 &sub_strict_overflow_p)
14974 && tree_expr_nonnegative_warnv_p (op1,
14975 &sub_strict_overflow_p))
14977 if (sub_strict_overflow_p)
14978 *strict_overflow_p = true;
14984 return (tree_expr_nonzero_warnv_p (op1,
14986 || tree_expr_nonzero_warnv_p (op0,
14987 strict_overflow_p));
14996 /* Return true when T is an address and is known to be nonzero.
14997 For floating point we further ensure that T is not denormal.
14998 Similar logic is present in nonzero_address in rtlanal.h.
15000 If the return value is based on the assumption that signed overflow
15001 is undefined, set *STRICT_OVERFLOW_P to true; otherwise, don't
15002 change *STRICT_OVERFLOW_P. */
15005 tree_single_nonzero_warnv_p (tree t, bool *strict_overflow_p)
15007 bool sub_strict_overflow_p;
15008 switch (TREE_CODE (t))
15011 return !integer_zerop (t);
15015 tree base = get_base_address (TREE_OPERAND (t, 0));
15020 /* Weak declarations may link to NULL. */
15021 if (VAR_OR_FUNCTION_DECL_P (base))
15022 return !DECL_WEAK (base);
15024 /* Constants are never weak. */
15025 if (CONSTANT_CLASS_P (base))
15032 sub_strict_overflow_p = false;
15033 if (tree_expr_nonzero_warnv_p (TREE_OPERAND (t, 1),
15034 &sub_strict_overflow_p)
15035 && tree_expr_nonzero_warnv_p (TREE_OPERAND (t, 2),
15036 &sub_strict_overflow_p))
15038 if (sub_strict_overflow_p)
15039 *strict_overflow_p = true;
15050 /* Return true when T is an address and is known to be nonzero.
15051 For floating point we further ensure that T is not denormal.
15052 Similar logic is present in nonzero_address in rtlanal.h.
15054 If the return value is based on the assumption that signed overflow
15055 is undefined, set *STRICT_OVERFLOW_P to true; otherwise, don't
15056 change *STRICT_OVERFLOW_P. */
15059 tree_expr_nonzero_warnv_p (tree t, bool *strict_overflow_p)
15061 tree type = TREE_TYPE (t);
15062 enum tree_code code;
15064 /* Doing something useful for floating point would need more work. */
15065 if (!INTEGRAL_TYPE_P (type) && !POINTER_TYPE_P (type))
15068 code = TREE_CODE (t);
15069 switch (TREE_CODE_CLASS (code))
15072 return tree_unary_nonzero_warnv_p (code, type, TREE_OPERAND (t, 0),
15073 strict_overflow_p);
15075 case tcc_comparison:
15076 return tree_binary_nonzero_warnv_p (code, type,
15077 TREE_OPERAND (t, 0),
15078 TREE_OPERAND (t, 1),
15079 strict_overflow_p);
15081 case tcc_declaration:
15082 case tcc_reference:
15083 return tree_single_nonzero_warnv_p (t, strict_overflow_p);
15091 case TRUTH_NOT_EXPR:
15092 return tree_unary_nonzero_warnv_p (code, type, TREE_OPERAND (t, 0),
15093 strict_overflow_p);
15095 case TRUTH_AND_EXPR:
15096 case TRUTH_OR_EXPR:
15097 case TRUTH_XOR_EXPR:
15098 return tree_binary_nonzero_warnv_p (code, type,
15099 TREE_OPERAND (t, 0),
15100 TREE_OPERAND (t, 1),
15101 strict_overflow_p);
15108 case WITH_SIZE_EXPR:
15112 return tree_single_nonzero_warnv_p (t, strict_overflow_p);
15114 case COMPOUND_EXPR:
15117 return tree_expr_nonzero_warnv_p (TREE_OPERAND (t, 1),
15118 strict_overflow_p);
15121 return tree_expr_nonzero_warnv_p (TREE_OPERAND (t, 0),
15122 strict_overflow_p);
15125 return alloca_call_p (t);
15133 /* Return true when T is an address and is known to be nonzero.
15134 Handle warnings about undefined signed overflow. */
15137 tree_expr_nonzero_p (tree t)
15139 bool ret, strict_overflow_p;
15141 strict_overflow_p = false;
15142 ret = tree_expr_nonzero_warnv_p (t, &strict_overflow_p);
15143 if (strict_overflow_p)
15144 fold_overflow_warning (("assuming signed overflow does not occur when "
15145 "determining that expression is always "
15147 WARN_STRICT_OVERFLOW_MISC);
15151 /* Given the components of a binary expression CODE, TYPE, OP0 and OP1,
15152 attempt to fold the expression to a constant without modifying TYPE,
15155 If the expression could be simplified to a constant, then return
15156 the constant. If the expression would not be simplified to a
15157 constant, then return NULL_TREE. */
15160 fold_binary_to_constant (enum tree_code code, tree type, tree op0, tree op1)
15162 tree tem = fold_binary (code, type, op0, op1);
15163 return (tem && TREE_CONSTANT (tem)) ? tem : NULL_TREE;
15166 /* Given the components of a unary expression CODE, TYPE and OP0,
15167 attempt to fold the expression to a constant without modifying
15170 If the expression could be simplified to a constant, then return
15171 the constant. If the expression would not be simplified to a
15172 constant, then return NULL_TREE. */
15175 fold_unary_to_constant (enum tree_code code, tree type, tree op0)
15177 tree tem = fold_unary (code, type, op0);
15178 return (tem && TREE_CONSTANT (tem)) ? tem : NULL_TREE;
15181 /* If EXP represents referencing an element in a constant string
15182 (either via pointer arithmetic or array indexing), return the
15183 tree representing the value accessed, otherwise return NULL. */
15186 fold_read_from_constant_string (tree exp)
15188 if ((TREE_CODE (exp) == INDIRECT_REF
15189 || TREE_CODE (exp) == ARRAY_REF)
15190 && TREE_CODE (TREE_TYPE (exp)) == INTEGER_TYPE)
15192 tree exp1 = TREE_OPERAND (exp, 0);
15196 if (TREE_CODE (exp) == INDIRECT_REF)
15197 string = string_constant (exp1, &index);
15200 tree low_bound = array_ref_low_bound (exp);
15201 index = fold_convert (sizetype, TREE_OPERAND (exp, 1));
15203 /* Optimize the special-case of a zero lower bound.
15205 We convert the low_bound to sizetype to avoid some problems
15206 with constant folding. (E.g. suppose the lower bound is 1,
15207 and its mode is QI. Without the conversion,l (ARRAY
15208 +(INDEX-(unsigned char)1)) becomes ((ARRAY+(-(unsigned char)1))
15209 +INDEX), which becomes (ARRAY+255+INDEX). Oops!) */
15210 if (! integer_zerop (low_bound))
15211 index = size_diffop (index, fold_convert (sizetype, low_bound));
15217 && TYPE_MODE (TREE_TYPE (exp)) == TYPE_MODE (TREE_TYPE (TREE_TYPE (string)))
15218 && TREE_CODE (string) == STRING_CST
15219 && TREE_CODE (index) == INTEGER_CST
15220 && compare_tree_int (index, TREE_STRING_LENGTH (string)) < 0
15221 && (GET_MODE_CLASS (TYPE_MODE (TREE_TYPE (TREE_TYPE (string))))
15223 && (GET_MODE_SIZE (TYPE_MODE (TREE_TYPE (TREE_TYPE (string)))) == 1))
15224 return build_int_cst_type (TREE_TYPE (exp),
15225 (TREE_STRING_POINTER (string)
15226 [TREE_INT_CST_LOW (index)]));
15231 /* Return the tree for neg (ARG0) when ARG0 is known to be either
15232 an integer constant, real, or fixed-point constant.
15234 TYPE is the type of the result. */
15237 fold_negate_const (tree arg0, tree type)
15239 tree t = NULL_TREE;
15241 switch (TREE_CODE (arg0))
15245 unsigned HOST_WIDE_INT low;
15246 HOST_WIDE_INT high;
15247 int overflow = neg_double (TREE_INT_CST_LOW (arg0),
15248 TREE_INT_CST_HIGH (arg0),
15250 t = force_fit_type_double (type, low, high, 1,
15251 (overflow | TREE_OVERFLOW (arg0))
15252 && !TYPE_UNSIGNED (type));
15257 t = build_real (type, REAL_VALUE_NEGATE (TREE_REAL_CST (arg0)));
15262 FIXED_VALUE_TYPE f;
15263 bool overflow_p = fixed_arithmetic (&f, NEGATE_EXPR,
15264 &(TREE_FIXED_CST (arg0)), NULL,
15265 TYPE_SATURATING (type));
15266 t = build_fixed (type, f);
15267 /* Propagate overflow flags. */
15268 if (overflow_p | TREE_OVERFLOW (arg0))
15269 TREE_OVERFLOW (t) = 1;
15274 gcc_unreachable ();
15280 /* Return the tree for abs (ARG0) when ARG0 is known to be either
15281 an integer constant or real constant.
15283 TYPE is the type of the result. */
15286 fold_abs_const (tree arg0, tree type)
15288 tree t = NULL_TREE;
15290 switch (TREE_CODE (arg0))
15293 /* If the value is unsigned, then the absolute value is
15294 the same as the ordinary value. */
15295 if (TYPE_UNSIGNED (type))
15297 /* Similarly, if the value is non-negative. */
15298 else if (INT_CST_LT (integer_minus_one_node, arg0))
15300 /* If the value is negative, then the absolute value is
15304 unsigned HOST_WIDE_INT low;
15305 HOST_WIDE_INT high;
15306 int overflow = neg_double (TREE_INT_CST_LOW (arg0),
15307 TREE_INT_CST_HIGH (arg0),
15309 t = force_fit_type_double (type, low, high, -1,
15310 overflow | TREE_OVERFLOW (arg0));
15315 if (REAL_VALUE_NEGATIVE (TREE_REAL_CST (arg0)))
15316 t = build_real (type, REAL_VALUE_NEGATE (TREE_REAL_CST (arg0)));
15322 gcc_unreachable ();
15328 /* Return the tree for not (ARG0) when ARG0 is known to be an integer
15329 constant. TYPE is the type of the result. */
15332 fold_not_const (tree arg0, tree type)
15334 tree t = NULL_TREE;
15336 gcc_assert (TREE_CODE (arg0) == INTEGER_CST);
15338 t = force_fit_type_double (type, ~TREE_INT_CST_LOW (arg0),
15339 ~TREE_INT_CST_HIGH (arg0), 0,
15340 TREE_OVERFLOW (arg0));
15345 /* Given CODE, a relational operator, the target type, TYPE and two
15346 constant operands OP0 and OP1, return the result of the
15347 relational operation. If the result is not a compile time
15348 constant, then return NULL_TREE. */
15351 fold_relational_const (enum tree_code code, tree type, tree op0, tree op1)
15353 int result, invert;
15355 /* From here on, the only cases we handle are when the result is
15356 known to be a constant. */
15358 if (TREE_CODE (op0) == REAL_CST && TREE_CODE (op1) == REAL_CST)
15360 const REAL_VALUE_TYPE *c0 = TREE_REAL_CST_PTR (op0);
15361 const REAL_VALUE_TYPE *c1 = TREE_REAL_CST_PTR (op1);
15363 /* Handle the cases where either operand is a NaN. */
15364 if (real_isnan (c0) || real_isnan (c1))
15374 case UNORDERED_EXPR:
15388 if (flag_trapping_math)
15394 gcc_unreachable ();
15397 return constant_boolean_node (result, type);
15400 return constant_boolean_node (real_compare (code, c0, c1), type);
15403 if (TREE_CODE (op0) == FIXED_CST && TREE_CODE (op1) == FIXED_CST)
15405 const FIXED_VALUE_TYPE *c0 = TREE_FIXED_CST_PTR (op0);
15406 const FIXED_VALUE_TYPE *c1 = TREE_FIXED_CST_PTR (op1);
15407 return constant_boolean_node (fixed_compare (code, c0, c1), type);
15410 /* Handle equality/inequality of complex constants. */
15411 if (TREE_CODE (op0) == COMPLEX_CST && TREE_CODE (op1) == COMPLEX_CST)
15413 tree rcond = fold_relational_const (code, type,
15414 TREE_REALPART (op0),
15415 TREE_REALPART (op1));
15416 tree icond = fold_relational_const (code, type,
15417 TREE_IMAGPART (op0),
15418 TREE_IMAGPART (op1));
15419 if (code == EQ_EXPR)
15420 return fold_build2 (TRUTH_ANDIF_EXPR, type, rcond, icond);
15421 else if (code == NE_EXPR)
15422 return fold_build2 (TRUTH_ORIF_EXPR, type, rcond, icond);
15427 /* From here on we only handle LT, LE, GT, GE, EQ and NE.
15429 To compute GT, swap the arguments and do LT.
15430 To compute GE, do LT and invert the result.
15431 To compute LE, swap the arguments, do LT and invert the result.
15432 To compute NE, do EQ and invert the result.
15434 Therefore, the code below must handle only EQ and LT. */
15436 if (code == LE_EXPR || code == GT_EXPR)
15441 code = swap_tree_comparison (code);
15444 /* Note that it is safe to invert for real values here because we
15445 have already handled the one case that it matters. */
15448 if (code == NE_EXPR || code == GE_EXPR)
15451 code = invert_tree_comparison (code, false);
15454 /* Compute a result for LT or EQ if args permit;
15455 Otherwise return T. */
15456 if (TREE_CODE (op0) == INTEGER_CST && TREE_CODE (op1) == INTEGER_CST)
15458 if (code == EQ_EXPR)
15459 result = tree_int_cst_equal (op0, op1);
15460 else if (TYPE_UNSIGNED (TREE_TYPE (op0)))
15461 result = INT_CST_LT_UNSIGNED (op0, op1);
15463 result = INT_CST_LT (op0, op1);
15470 return constant_boolean_node (result, type);
15473 /* If necessary, return a CLEANUP_POINT_EXPR for EXPR with the
15474 indicated TYPE. If no CLEANUP_POINT_EXPR is necessary, return EXPR
15478 fold_build_cleanup_point_expr (tree type, tree expr)
15480 /* If the expression does not have side effects then we don't have to wrap
15481 it with a cleanup point expression. */
15482 if (!TREE_SIDE_EFFECTS (expr))
15485 /* If the expression is a return, check to see if the expression inside the
15486 return has no side effects or the right hand side of the modify expression
15487 inside the return. If either don't have side effects set we don't need to
15488 wrap the expression in a cleanup point expression. Note we don't check the
15489 left hand side of the modify because it should always be a return decl. */
15490 if (TREE_CODE (expr) == RETURN_EXPR)
15492 tree op = TREE_OPERAND (expr, 0);
15493 if (!op || !TREE_SIDE_EFFECTS (op))
15495 op = TREE_OPERAND (op, 1);
15496 if (!TREE_SIDE_EFFECTS (op))
15500 return build1 (CLEANUP_POINT_EXPR, type, expr);
15503 /* Given a pointer value OP0 and a type TYPE, return a simplified version
15504 of an indirection through OP0, or NULL_TREE if no simplification is
15508 fold_indirect_ref_1 (tree type, tree op0)
15514 subtype = TREE_TYPE (sub);
15515 if (!POINTER_TYPE_P (subtype))
15518 if (TREE_CODE (sub) == ADDR_EXPR)
15520 tree op = TREE_OPERAND (sub, 0);
15521 tree optype = TREE_TYPE (op);
15522 /* *&CONST_DECL -> to the value of the const decl. */
15523 if (TREE_CODE (op) == CONST_DECL)
15524 return DECL_INITIAL (op);
15525 /* *&p => p; make sure to handle *&"str"[cst] here. */
15526 if (type == optype)
15528 tree fop = fold_read_from_constant_string (op);
15534 /* *(foo *)&fooarray => fooarray[0] */
15535 else if (TREE_CODE (optype) == ARRAY_TYPE
15536 && type == TREE_TYPE (optype))
15538 tree type_domain = TYPE_DOMAIN (optype);
15539 tree min_val = size_zero_node;
15540 if (type_domain && TYPE_MIN_VALUE (type_domain))
15541 min_val = TYPE_MIN_VALUE (type_domain);
15542 return build4 (ARRAY_REF, type, op, min_val, NULL_TREE, NULL_TREE);
15544 /* *(foo *)&complexfoo => __real__ complexfoo */
15545 else if (TREE_CODE (optype) == COMPLEX_TYPE
15546 && type == TREE_TYPE (optype))
15547 return fold_build1 (REALPART_EXPR, type, op);
15548 /* *(foo *)&vectorfoo => BIT_FIELD_REF<vectorfoo,...> */
15549 else if (TREE_CODE (optype) == VECTOR_TYPE
15550 && type == TREE_TYPE (optype))
15552 tree part_width = TYPE_SIZE (type);
15553 tree index = bitsize_int (0);
15554 return fold_build3 (BIT_FIELD_REF, type, op, part_width, index);
15558 /* ((foo*)&vectorfoo)[1] => BIT_FIELD_REF<vectorfoo,...> */
15559 if (TREE_CODE (sub) == POINTER_PLUS_EXPR
15560 && TREE_CODE (TREE_OPERAND (sub, 1)) == INTEGER_CST)
15562 tree op00 = TREE_OPERAND (sub, 0);
15563 tree op01 = TREE_OPERAND (sub, 1);
15567 op00type = TREE_TYPE (op00);
15568 if (TREE_CODE (op00) == ADDR_EXPR
15569 && TREE_CODE (TREE_TYPE (op00type)) == VECTOR_TYPE
15570 && type == TREE_TYPE (TREE_TYPE (op00type)))
15572 HOST_WIDE_INT offset = tree_low_cst (op01, 0);
15573 tree part_width = TYPE_SIZE (type);
15574 unsigned HOST_WIDE_INT part_widthi = tree_low_cst (part_width, 0)/BITS_PER_UNIT;
15575 unsigned HOST_WIDE_INT indexi = offset * BITS_PER_UNIT;
15576 tree index = bitsize_int (indexi);
15578 if (offset/part_widthi <= TYPE_VECTOR_SUBPARTS (TREE_TYPE (op00type)))
15579 return fold_build3 (BIT_FIELD_REF, type, TREE_OPERAND (op00, 0),
15580 part_width, index);
15586 /* ((foo*)&complexfoo)[1] => __imag__ complexfoo */
15587 if (TREE_CODE (sub) == POINTER_PLUS_EXPR
15588 && TREE_CODE (TREE_OPERAND (sub, 1)) == INTEGER_CST)
15590 tree op00 = TREE_OPERAND (sub, 0);
15591 tree op01 = TREE_OPERAND (sub, 1);
15595 op00type = TREE_TYPE (op00);
15596 if (TREE_CODE (op00) == ADDR_EXPR
15597 && TREE_CODE (TREE_TYPE (op00type)) == COMPLEX_TYPE
15598 && type == TREE_TYPE (TREE_TYPE (op00type)))
15600 tree size = TYPE_SIZE_UNIT (type);
15601 if (tree_int_cst_equal (size, op01))
15602 return fold_build1 (IMAGPART_EXPR, type, TREE_OPERAND (op00, 0));
15606 /* *(foo *)fooarrptr => (*fooarrptr)[0] */
15607 if (TREE_CODE (TREE_TYPE (subtype)) == ARRAY_TYPE
15608 && type == TREE_TYPE (TREE_TYPE (subtype)))
15611 tree min_val = size_zero_node;
15612 sub = build_fold_indirect_ref (sub);
15613 type_domain = TYPE_DOMAIN (TREE_TYPE (sub));
15614 if (type_domain && TYPE_MIN_VALUE (type_domain))
15615 min_val = TYPE_MIN_VALUE (type_domain);
15616 return build4 (ARRAY_REF, type, sub, min_val, NULL_TREE, NULL_TREE);
15622 /* Builds an expression for an indirection through T, simplifying some
15626 build_fold_indirect_ref (tree t)
15628 tree type = TREE_TYPE (TREE_TYPE (t));
15629 tree sub = fold_indirect_ref_1 (type, t);
15634 return build1 (INDIRECT_REF, type, t);
15637 /* Given an INDIRECT_REF T, return either T or a simplified version. */
15640 fold_indirect_ref (tree t)
15642 tree sub = fold_indirect_ref_1 (TREE_TYPE (t), TREE_OPERAND (t, 0));
15650 /* Strip non-trapping, non-side-effecting tree nodes from an expression
15651 whose result is ignored. The type of the returned tree need not be
15652 the same as the original expression. */
15655 fold_ignored_result (tree t)
15657 if (!TREE_SIDE_EFFECTS (t))
15658 return integer_zero_node;
15661 switch (TREE_CODE_CLASS (TREE_CODE (t)))
15664 t = TREE_OPERAND (t, 0);
15668 case tcc_comparison:
15669 if (!TREE_SIDE_EFFECTS (TREE_OPERAND (t, 1)))
15670 t = TREE_OPERAND (t, 0);
15671 else if (!TREE_SIDE_EFFECTS (TREE_OPERAND (t, 0)))
15672 t = TREE_OPERAND (t, 1);
15677 case tcc_expression:
15678 switch (TREE_CODE (t))
15680 case COMPOUND_EXPR:
15681 if (TREE_SIDE_EFFECTS (TREE_OPERAND (t, 1)))
15683 t = TREE_OPERAND (t, 0);
15687 if (TREE_SIDE_EFFECTS (TREE_OPERAND (t, 1))
15688 || TREE_SIDE_EFFECTS (TREE_OPERAND (t, 2)))
15690 t = TREE_OPERAND (t, 0);
15703 /* Return the value of VALUE, rounded up to a multiple of DIVISOR.
15704 This can only be applied to objects of a sizetype. */
15707 round_up (tree value, int divisor)
15709 tree div = NULL_TREE;
15711 gcc_assert (divisor > 0);
15715 /* See if VALUE is already a multiple of DIVISOR. If so, we don't
15716 have to do anything. Only do this when we are not given a const,
15717 because in that case, this check is more expensive than just
15719 if (TREE_CODE (value) != INTEGER_CST)
15721 div = build_int_cst (TREE_TYPE (value), divisor);
15723 if (multiple_of_p (TREE_TYPE (value), value, div))
15727 /* If divisor is a power of two, simplify this to bit manipulation. */
15728 if (divisor == (divisor & -divisor))
15730 if (TREE_CODE (value) == INTEGER_CST)
15732 unsigned HOST_WIDE_INT low = TREE_INT_CST_LOW (value);
15733 unsigned HOST_WIDE_INT high;
15736 if ((low & (divisor - 1)) == 0)
15739 overflow_p = TREE_OVERFLOW (value);
15740 high = TREE_INT_CST_HIGH (value);
15741 low &= ~(divisor - 1);
15750 return force_fit_type_double (TREE_TYPE (value), low, high,
15757 t = build_int_cst (TREE_TYPE (value), divisor - 1);
15758 value = size_binop (PLUS_EXPR, value, t);
15759 t = build_int_cst (TREE_TYPE (value), -divisor);
15760 value = size_binop (BIT_AND_EXPR, value, t);
15766 div = build_int_cst (TREE_TYPE (value), divisor);
15767 value = size_binop (CEIL_DIV_EXPR, value, div);
15768 value = size_binop (MULT_EXPR, value, div);
15774 /* Likewise, but round down. */
15777 round_down (tree value, int divisor)
15779 tree div = NULL_TREE;
15781 gcc_assert (divisor > 0);
15785 /* See if VALUE is already a multiple of DIVISOR. If so, we don't
15786 have to do anything. Only do this when we are not given a const,
15787 because in that case, this check is more expensive than just
15789 if (TREE_CODE (value) != INTEGER_CST)
15791 div = build_int_cst (TREE_TYPE (value), divisor);
15793 if (multiple_of_p (TREE_TYPE (value), value, div))
15797 /* If divisor is a power of two, simplify this to bit manipulation. */
15798 if (divisor == (divisor & -divisor))
15802 t = build_int_cst (TREE_TYPE (value), -divisor);
15803 value = size_binop (BIT_AND_EXPR, value, t);
15808 div = build_int_cst (TREE_TYPE (value), divisor);
15809 value = size_binop (FLOOR_DIV_EXPR, value, div);
15810 value = size_binop (MULT_EXPR, value, div);
15816 /* Returns the pointer to the base of the object addressed by EXP and
15817 extracts the information about the offset of the access, storing it
15818 to PBITPOS and POFFSET. */
15821 split_address_to_core_and_offset (tree exp,
15822 HOST_WIDE_INT *pbitpos, tree *poffset)
15825 enum machine_mode mode;
15826 int unsignedp, volatilep;
15827 HOST_WIDE_INT bitsize;
15829 if (TREE_CODE (exp) == ADDR_EXPR)
15831 core = get_inner_reference (TREE_OPERAND (exp, 0), &bitsize, pbitpos,
15832 poffset, &mode, &unsignedp, &volatilep,
15834 core = build_fold_addr_expr (core);
15840 *poffset = NULL_TREE;
15846 /* Returns true if addresses of E1 and E2 differ by a constant, false
15847 otherwise. If they do, E1 - E2 is stored in *DIFF. */
15850 ptr_difference_const (tree e1, tree e2, HOST_WIDE_INT *diff)
15853 HOST_WIDE_INT bitpos1, bitpos2;
15854 tree toffset1, toffset2, tdiff, type;
15856 core1 = split_address_to_core_and_offset (e1, &bitpos1, &toffset1);
15857 core2 = split_address_to_core_and_offset (e2, &bitpos2, &toffset2);
15859 if (bitpos1 % BITS_PER_UNIT != 0
15860 || bitpos2 % BITS_PER_UNIT != 0
15861 || !operand_equal_p (core1, core2, 0))
15864 if (toffset1 && toffset2)
15866 type = TREE_TYPE (toffset1);
15867 if (type != TREE_TYPE (toffset2))
15868 toffset2 = fold_convert (type, toffset2);
15870 tdiff = fold_build2 (MINUS_EXPR, type, toffset1, toffset2);
15871 if (!cst_and_fits_in_hwi (tdiff))
15874 *diff = int_cst_value (tdiff);
15876 else if (toffset1 || toffset2)
15878 /* If only one of the offsets is non-constant, the difference cannot
15885 *diff += (bitpos1 - bitpos2) / BITS_PER_UNIT;
15889 /* Simplify the floating point expression EXP when the sign of the
15890 result is not significant. Return NULL_TREE if no simplification
15894 fold_strip_sign_ops (tree exp)
15898 switch (TREE_CODE (exp))
15902 arg0 = fold_strip_sign_ops (TREE_OPERAND (exp, 0));
15903 return arg0 ? arg0 : TREE_OPERAND (exp, 0);
15907 if (HONOR_SIGN_DEPENDENT_ROUNDING (TYPE_MODE (TREE_TYPE (exp))))
15909 arg0 = fold_strip_sign_ops (TREE_OPERAND (exp, 0));
15910 arg1 = fold_strip_sign_ops (TREE_OPERAND (exp, 1));
15911 if (arg0 != NULL_TREE || arg1 != NULL_TREE)
15912 return fold_build2 (TREE_CODE (exp), TREE_TYPE (exp),
15913 arg0 ? arg0 : TREE_OPERAND (exp, 0),
15914 arg1 ? arg1 : TREE_OPERAND (exp, 1));
15917 case COMPOUND_EXPR:
15918 arg0 = TREE_OPERAND (exp, 0);
15919 arg1 = fold_strip_sign_ops (TREE_OPERAND (exp, 1));
15921 return fold_build2 (COMPOUND_EXPR, TREE_TYPE (exp), arg0, arg1);
15925 arg0 = fold_strip_sign_ops (TREE_OPERAND (exp, 1));
15926 arg1 = fold_strip_sign_ops (TREE_OPERAND (exp, 2));
15928 return fold_build3 (COND_EXPR, TREE_TYPE (exp), TREE_OPERAND (exp, 0),
15929 arg0 ? arg0 : TREE_OPERAND (exp, 1),
15930 arg1 ? arg1 : TREE_OPERAND (exp, 2));
15935 const enum built_in_function fcode = builtin_mathfn_code (exp);
15938 CASE_FLT_FN (BUILT_IN_COPYSIGN):
15939 /* Strip copysign function call, return the 1st argument. */
15940 arg0 = CALL_EXPR_ARG (exp, 0);
15941 arg1 = CALL_EXPR_ARG (exp, 1);
15942 return omit_one_operand (TREE_TYPE (exp), arg0, arg1);
15945 /* Strip sign ops from the argument of "odd" math functions. */
15946 if (negate_mathfn_p (fcode))
15948 arg0 = fold_strip_sign_ops (CALL_EXPR_ARG (exp, 0));
15950 return build_call_expr (get_callee_fndecl (exp), 1, arg0);