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, 2010
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 (location_t, 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 (location_t, tree, tree, tree, tree, tree);
109 static tree pedantic_omit_one_operand_loc (location_t, tree, tree, tree);
110 static tree distribute_bit_expr (location_t, enum tree_code, tree, tree, tree);
111 static tree make_bit_field_ref (location_t, tree, tree,
112 HOST_WIDE_INT, HOST_WIDE_INT, int);
113 static tree optimize_bit_field_compare (location_t, enum tree_code,
115 static tree decode_field_reference (location_t, tree, HOST_WIDE_INT *,
117 enum machine_mode *, int *, int *,
119 static int all_ones_mask_p (const_tree, int);
120 static tree sign_bit_p (tree, const_tree);
121 static int simple_operand_p (const_tree);
122 static tree range_binop (enum tree_code, tree, tree, int, tree, int);
123 static tree range_predecessor (tree);
124 static tree range_successor (tree);
125 extern tree make_range (tree, int *, tree *, tree *, bool *);
126 extern bool merge_ranges (int *, tree *, tree *, int, tree, tree, int,
128 static tree fold_range_test (location_t, enum tree_code, tree, tree, tree);
129 static tree fold_cond_expr_with_comparison (location_t, tree, tree, tree, tree);
130 static tree unextend (tree, int, int, tree);
131 static tree fold_truthop (location_t, enum tree_code, tree, tree, tree);
132 static tree optimize_minmax_comparison (location_t, enum tree_code,
134 static tree extract_muldiv (tree, tree, enum tree_code, tree, bool *);
135 static tree extract_muldiv_1 (tree, tree, enum tree_code, tree, bool *);
136 static tree fold_binary_op_with_conditional_arg (location_t,
137 enum tree_code, tree,
140 static tree fold_mathfn_compare (location_t,
141 enum built_in_function, enum tree_code,
143 static tree fold_inf_compare (location_t, enum tree_code, tree, tree, tree);
144 static tree fold_div_compare (location_t, enum tree_code, tree, tree, tree);
145 static bool reorder_operands_p (const_tree, const_tree);
146 static tree fold_negate_const (tree, tree);
147 static tree fold_not_const (tree, tree);
148 static tree fold_relational_const (enum tree_code, tree, tree, tree);
149 static tree fold_convert_const (enum tree_code, tree, tree);
152 /* We know that A1 + B1 = SUM1, using 2's complement arithmetic and ignoring
153 overflow. Suppose A, B and SUM have the same respective signs as A1, B1,
154 and SUM1. Then this yields nonzero if overflow occurred during the
157 Overflow occurs if A and B have the same sign, but A and SUM differ in
158 sign. Use `^' to test whether signs differ, and `< 0' to isolate the
160 #define OVERFLOW_SUM_SIGN(a, b, sum) ((~((a) ^ (b)) & ((a) ^ (sum))) < 0)
162 /* To do constant folding on INTEGER_CST nodes requires two-word arithmetic.
163 We do that by representing the two-word integer in 4 words, with only
164 HOST_BITS_PER_WIDE_INT / 2 bits stored in each word, as a positive
165 number. The value of the word is LOWPART + HIGHPART * BASE. */
168 ((x) & (((unsigned HOST_WIDE_INT) 1 << (HOST_BITS_PER_WIDE_INT / 2)) - 1))
169 #define HIGHPART(x) \
170 ((unsigned HOST_WIDE_INT) (x) >> HOST_BITS_PER_WIDE_INT / 2)
171 #define BASE ((unsigned HOST_WIDE_INT) 1 << HOST_BITS_PER_WIDE_INT / 2)
173 /* Unpack a two-word integer into 4 words.
174 LOW and HI are the integer, as two `HOST_WIDE_INT' pieces.
175 WORDS points to the array of HOST_WIDE_INTs. */
178 encode (HOST_WIDE_INT *words, unsigned HOST_WIDE_INT low, HOST_WIDE_INT hi)
180 words[0] = LOWPART (low);
181 words[1] = HIGHPART (low);
182 words[2] = LOWPART (hi);
183 words[3] = HIGHPART (hi);
186 /* Pack an array of 4 words into a two-word integer.
187 WORDS points to the array of words.
188 The integer is stored into *LOW and *HI as two `HOST_WIDE_INT' pieces. */
191 decode (HOST_WIDE_INT *words, unsigned HOST_WIDE_INT *low,
194 *low = words[0] + words[1] * BASE;
195 *hi = words[2] + words[3] * BASE;
198 /* Force the double-word integer L1, H1 to be within the range of the
199 integer type TYPE. Stores the properly truncated and sign-extended
200 double-word integer in *LV, *HV. Returns true if the operation
201 overflows, that is, argument and result are different. */
204 fit_double_type (unsigned HOST_WIDE_INT l1, HOST_WIDE_INT h1,
205 unsigned HOST_WIDE_INT *lv, HOST_WIDE_INT *hv, const_tree type)
207 unsigned HOST_WIDE_INT low0 = l1;
208 HOST_WIDE_INT high0 = h1;
209 unsigned int prec = TYPE_PRECISION (type);
210 int sign_extended_type;
212 /* Size types *are* sign extended. */
213 sign_extended_type = (!TYPE_UNSIGNED (type)
214 || (TREE_CODE (type) == INTEGER_TYPE
215 && TYPE_IS_SIZETYPE (type)));
217 /* First clear all bits that are beyond the type's precision. */
218 if (prec >= 2 * HOST_BITS_PER_WIDE_INT)
220 else if (prec > HOST_BITS_PER_WIDE_INT)
221 h1 &= ~((HOST_WIDE_INT) (-1) << (prec - HOST_BITS_PER_WIDE_INT));
225 if (prec < HOST_BITS_PER_WIDE_INT)
226 l1 &= ~((HOST_WIDE_INT) (-1) << prec);
229 /* Then do sign extension if necessary. */
230 if (!sign_extended_type)
231 /* No sign extension */;
232 else if (prec >= 2 * HOST_BITS_PER_WIDE_INT)
233 /* Correct width already. */;
234 else if (prec > HOST_BITS_PER_WIDE_INT)
236 /* Sign extend top half? */
237 if (h1 & ((unsigned HOST_WIDE_INT)1
238 << (prec - HOST_BITS_PER_WIDE_INT - 1)))
239 h1 |= (HOST_WIDE_INT) (-1) << (prec - HOST_BITS_PER_WIDE_INT);
241 else if (prec == HOST_BITS_PER_WIDE_INT)
243 if ((HOST_WIDE_INT)l1 < 0)
248 /* Sign extend bottom half? */
249 if (l1 & ((unsigned HOST_WIDE_INT)1 << (prec - 1)))
252 l1 |= (HOST_WIDE_INT)(-1) << prec;
259 /* If the value didn't fit, signal overflow. */
260 return l1 != low0 || h1 != high0;
263 /* We force the double-int HIGH:LOW to the range of the type TYPE by
264 sign or zero extending it.
265 OVERFLOWABLE indicates if we are interested
266 in overflow of the value, when >0 we are only interested in signed
267 overflow, for <0 we are interested in any overflow. OVERFLOWED
268 indicates whether overflow has already occurred. CONST_OVERFLOWED
269 indicates whether constant overflow has already occurred. We force
270 T's value to be within range of T's type (by setting to 0 or 1 all
271 the bits outside the type's range). We set TREE_OVERFLOWED if,
272 OVERFLOWED is nonzero,
273 or OVERFLOWABLE is >0 and signed overflow occurs
274 or OVERFLOWABLE is <0 and any overflow occurs
275 We return a new tree node for the extended double-int. The node
276 is shared if no overflow flags are set. */
279 force_fit_type_double (tree type, unsigned HOST_WIDE_INT low,
280 HOST_WIDE_INT high, int overflowable,
283 int sign_extended_type;
286 /* Size types *are* sign extended. */
287 sign_extended_type = (!TYPE_UNSIGNED (type)
288 || (TREE_CODE (type) == INTEGER_TYPE
289 && TYPE_IS_SIZETYPE (type)));
291 overflow = fit_double_type (low, high, &low, &high, type);
293 /* If we need to set overflow flags, return a new unshared node. */
294 if (overflowed || overflow)
298 || (overflowable > 0 && sign_extended_type))
300 tree t = make_node (INTEGER_CST);
301 TREE_INT_CST_LOW (t) = low;
302 TREE_INT_CST_HIGH (t) = high;
303 TREE_TYPE (t) = type;
304 TREE_OVERFLOW (t) = 1;
309 /* Else build a shared node. */
310 return build_int_cst_wide (type, low, high);
313 /* Add two doubleword integers with doubleword result.
314 Return nonzero if the operation overflows according to UNSIGNED_P.
315 Each argument is given as two `HOST_WIDE_INT' pieces.
316 One argument is L1 and H1; the other, L2 and H2.
317 The value is stored as two `HOST_WIDE_INT' pieces in *LV and *HV. */
320 add_double_with_sign (unsigned HOST_WIDE_INT l1, HOST_WIDE_INT h1,
321 unsigned HOST_WIDE_INT l2, HOST_WIDE_INT h2,
322 unsigned HOST_WIDE_INT *lv, HOST_WIDE_INT *hv,
325 unsigned HOST_WIDE_INT l;
329 h = (HOST_WIDE_INT) ((unsigned HOST_WIDE_INT) h1
330 + (unsigned HOST_WIDE_INT) h2
337 return ((unsigned HOST_WIDE_INT) h < (unsigned HOST_WIDE_INT) h1
341 return OVERFLOW_SUM_SIGN (h1, h2, h);
344 /* Negate a doubleword integer with doubleword result.
345 Return nonzero if the operation overflows, assuming it's signed.
346 The argument is given as two `HOST_WIDE_INT' pieces in L1 and H1.
347 The value is stored as two `HOST_WIDE_INT' pieces in *LV and *HV. */
350 neg_double (unsigned HOST_WIDE_INT l1, HOST_WIDE_INT h1,
351 unsigned HOST_WIDE_INT *lv, HOST_WIDE_INT *hv)
357 return (*hv & h1) < 0;
367 /* Multiply two doubleword integers with doubleword result.
368 Return nonzero if the operation overflows according to UNSIGNED_P.
369 Each argument is given as two `HOST_WIDE_INT' pieces.
370 One argument is L1 and H1; the other, L2 and H2.
371 The value is stored as two `HOST_WIDE_INT' pieces in *LV and *HV. */
374 mul_double_with_sign (unsigned HOST_WIDE_INT l1, HOST_WIDE_INT h1,
375 unsigned HOST_WIDE_INT l2, HOST_WIDE_INT h2,
376 unsigned HOST_WIDE_INT *lv, HOST_WIDE_INT *hv,
379 HOST_WIDE_INT arg1[4];
380 HOST_WIDE_INT arg2[4];
381 HOST_WIDE_INT prod[4 * 2];
382 unsigned HOST_WIDE_INT carry;
384 unsigned HOST_WIDE_INT toplow, neglow;
385 HOST_WIDE_INT tophigh, neghigh;
387 encode (arg1, l1, h1);
388 encode (arg2, l2, h2);
390 memset (prod, 0, sizeof prod);
392 for (i = 0; i < 4; i++)
395 for (j = 0; j < 4; j++)
398 /* This product is <= 0xFFFE0001, the sum <= 0xFFFF0000. */
399 carry += arg1[i] * arg2[j];
400 /* Since prod[p] < 0xFFFF, this sum <= 0xFFFFFFFF. */
402 prod[k] = LOWPART (carry);
403 carry = HIGHPART (carry);
408 decode (prod, lv, hv);
409 decode (prod + 4, &toplow, &tophigh);
411 /* Unsigned overflow is immediate. */
413 return (toplow | tophigh) != 0;
415 /* Check for signed overflow by calculating the signed representation of the
416 top half of the result; it should agree with the low half's sign bit. */
419 neg_double (l2, h2, &neglow, &neghigh);
420 add_double (neglow, neghigh, toplow, tophigh, &toplow, &tophigh);
424 neg_double (l1, h1, &neglow, &neghigh);
425 add_double (neglow, neghigh, toplow, tophigh, &toplow, &tophigh);
427 return (*hv < 0 ? ~(toplow & tophigh) : toplow | tophigh) != 0;
430 /* Shift the doubleword integer in L1, H1 left by COUNT places
431 keeping only PREC bits of result.
432 Shift right if COUNT is negative.
433 ARITH nonzero specifies arithmetic shifting; otherwise use logical shift.
434 Store the value as two `HOST_WIDE_INT' pieces in *LV and *HV. */
437 lshift_double (unsigned HOST_WIDE_INT l1, HOST_WIDE_INT h1,
438 HOST_WIDE_INT count, unsigned int prec,
439 unsigned HOST_WIDE_INT *lv, HOST_WIDE_INT *hv, int arith)
441 unsigned HOST_WIDE_INT signmask;
445 rshift_double (l1, h1, -count, prec, lv, hv, arith);
449 if (SHIFT_COUNT_TRUNCATED)
452 if (count >= 2 * HOST_BITS_PER_WIDE_INT)
454 /* Shifting by the host word size is undefined according to the
455 ANSI standard, so we must handle this as a special case. */
459 else if (count >= HOST_BITS_PER_WIDE_INT)
461 *hv = l1 << (count - HOST_BITS_PER_WIDE_INT);
466 *hv = (((unsigned HOST_WIDE_INT) h1 << count)
467 | (l1 >> (HOST_BITS_PER_WIDE_INT - count - 1) >> 1));
471 /* Sign extend all bits that are beyond the precision. */
473 signmask = -((prec > HOST_BITS_PER_WIDE_INT
474 ? ((unsigned HOST_WIDE_INT) *hv
475 >> (prec - HOST_BITS_PER_WIDE_INT - 1))
476 : (*lv >> (prec - 1))) & 1);
478 if (prec >= 2 * HOST_BITS_PER_WIDE_INT)
480 else if (prec >= HOST_BITS_PER_WIDE_INT)
482 *hv &= ~((HOST_WIDE_INT) (-1) << (prec - HOST_BITS_PER_WIDE_INT));
483 *hv |= signmask << (prec - HOST_BITS_PER_WIDE_INT);
488 *lv &= ~((unsigned HOST_WIDE_INT) (-1) << prec);
489 *lv |= signmask << prec;
493 /* Shift the doubleword integer in L1, H1 right by COUNT places
494 keeping only PREC bits of result. COUNT must be positive.
495 ARITH nonzero specifies arithmetic shifting; otherwise use logical shift.
496 Store the value as two `HOST_WIDE_INT' pieces in *LV and *HV. */
499 rshift_double (unsigned HOST_WIDE_INT l1, HOST_WIDE_INT h1,
500 HOST_WIDE_INT count, unsigned int prec,
501 unsigned HOST_WIDE_INT *lv, HOST_WIDE_INT *hv,
504 unsigned HOST_WIDE_INT signmask;
507 ? -((unsigned HOST_WIDE_INT) h1 >> (HOST_BITS_PER_WIDE_INT - 1))
510 if (SHIFT_COUNT_TRUNCATED)
513 if (count >= 2 * HOST_BITS_PER_WIDE_INT)
515 /* Shifting by the host word size is undefined according to the
516 ANSI standard, so we must handle this as a special case. */
520 else if (count >= HOST_BITS_PER_WIDE_INT)
523 *lv = (unsigned HOST_WIDE_INT) h1 >> (count - HOST_BITS_PER_WIDE_INT);
527 *hv = (unsigned HOST_WIDE_INT) h1 >> count;
529 | ((unsigned HOST_WIDE_INT) h1 << (HOST_BITS_PER_WIDE_INT - count - 1) << 1));
532 /* Zero / sign extend all bits that are beyond the precision. */
534 if (count >= (HOST_WIDE_INT)prec)
539 else if ((prec - count) >= 2 * HOST_BITS_PER_WIDE_INT)
541 else if ((prec - count) >= HOST_BITS_PER_WIDE_INT)
543 *hv &= ~((HOST_WIDE_INT) (-1) << (prec - count - HOST_BITS_PER_WIDE_INT));
544 *hv |= signmask << (prec - count - HOST_BITS_PER_WIDE_INT);
549 *lv &= ~((unsigned HOST_WIDE_INT) (-1) << (prec - count));
550 *lv |= signmask << (prec - count);
554 /* Rotate the doubleword integer in L1, H1 left by COUNT places
555 keeping only PREC bits of result.
556 Rotate right if COUNT is negative.
557 Store the value as two `HOST_WIDE_INT' pieces in *LV and *HV. */
560 lrotate_double (unsigned HOST_WIDE_INT l1, HOST_WIDE_INT h1,
561 HOST_WIDE_INT count, unsigned int prec,
562 unsigned HOST_WIDE_INT *lv, HOST_WIDE_INT *hv)
564 unsigned HOST_WIDE_INT s1l, s2l;
565 HOST_WIDE_INT s1h, s2h;
571 lshift_double (l1, h1, count, prec, &s1l, &s1h, 0);
572 rshift_double (l1, h1, prec - count, prec, &s2l, &s2h, 0);
577 /* Rotate the doubleword integer in L1, H1 left by COUNT places
578 keeping only PREC bits of result. COUNT must be positive.
579 Store the value as two `HOST_WIDE_INT' pieces in *LV and *HV. */
582 rrotate_double (unsigned HOST_WIDE_INT l1, HOST_WIDE_INT h1,
583 HOST_WIDE_INT count, unsigned int prec,
584 unsigned HOST_WIDE_INT *lv, HOST_WIDE_INT *hv)
586 unsigned HOST_WIDE_INT s1l, s2l;
587 HOST_WIDE_INT s1h, s2h;
593 rshift_double (l1, h1, count, prec, &s1l, &s1h, 0);
594 lshift_double (l1, h1, prec - count, prec, &s2l, &s2h, 0);
599 /* Divide doubleword integer LNUM, HNUM by doubleword integer LDEN, HDEN
600 for a quotient (stored in *LQUO, *HQUO) and remainder (in *LREM, *HREM).
601 CODE is a tree code for a kind of division, one of
602 TRUNC_DIV_EXPR, FLOOR_DIV_EXPR, CEIL_DIV_EXPR, ROUND_DIV_EXPR
604 It controls how the quotient is rounded to an integer.
605 Return nonzero if the operation overflows.
606 UNS nonzero says do unsigned division. */
609 div_and_round_double (enum tree_code code, int uns,
610 unsigned HOST_WIDE_INT lnum_orig, /* num == numerator == dividend */
611 HOST_WIDE_INT hnum_orig,
612 unsigned HOST_WIDE_INT lden_orig, /* den == denominator == divisor */
613 HOST_WIDE_INT hden_orig,
614 unsigned HOST_WIDE_INT *lquo,
615 HOST_WIDE_INT *hquo, unsigned HOST_WIDE_INT *lrem,
619 HOST_WIDE_INT num[4 + 1]; /* extra element for scaling. */
620 HOST_WIDE_INT den[4], quo[4];
622 unsigned HOST_WIDE_INT work;
623 unsigned HOST_WIDE_INT carry = 0;
624 unsigned HOST_WIDE_INT lnum = lnum_orig;
625 HOST_WIDE_INT hnum = hnum_orig;
626 unsigned HOST_WIDE_INT lden = lden_orig;
627 HOST_WIDE_INT hden = hden_orig;
630 if (hden == 0 && lden == 0)
631 overflow = 1, lden = 1;
633 /* Calculate quotient sign and convert operands to unsigned. */
639 /* (minimum integer) / (-1) is the only overflow case. */
640 if (neg_double (lnum, hnum, &lnum, &hnum)
641 && ((HOST_WIDE_INT) lden & hden) == -1)
647 neg_double (lden, hden, &lden, &hden);
651 if (hnum == 0 && hden == 0)
652 { /* single precision */
654 /* This unsigned division rounds toward zero. */
660 { /* trivial case: dividend < divisor */
661 /* hden != 0 already checked. */
668 memset (quo, 0, sizeof quo);
670 memset (num, 0, sizeof num); /* to zero 9th element */
671 memset (den, 0, sizeof den);
673 encode (num, lnum, hnum);
674 encode (den, lden, hden);
676 /* Special code for when the divisor < BASE. */
677 if (hden == 0 && lden < (unsigned HOST_WIDE_INT) BASE)
679 /* hnum != 0 already checked. */
680 for (i = 4 - 1; i >= 0; i--)
682 work = num[i] + carry * BASE;
683 quo[i] = work / lden;
689 /* Full double precision division,
690 with thanks to Don Knuth's "Seminumerical Algorithms". */
691 int num_hi_sig, den_hi_sig;
692 unsigned HOST_WIDE_INT quo_est, scale;
694 /* Find the highest nonzero divisor digit. */
695 for (i = 4 - 1;; i--)
702 /* Insure that the first digit of the divisor is at least BASE/2.
703 This is required by the quotient digit estimation algorithm. */
705 scale = BASE / (den[den_hi_sig] + 1);
707 { /* scale divisor and dividend */
709 for (i = 0; i <= 4 - 1; i++)
711 work = (num[i] * scale) + carry;
712 num[i] = LOWPART (work);
713 carry = HIGHPART (work);
718 for (i = 0; i <= 4 - 1; i++)
720 work = (den[i] * scale) + carry;
721 den[i] = LOWPART (work);
722 carry = HIGHPART (work);
723 if (den[i] != 0) den_hi_sig = i;
730 for (i = num_hi_sig - den_hi_sig - 1; i >= 0; i--)
732 /* Guess the next quotient digit, quo_est, by dividing the first
733 two remaining dividend digits by the high order quotient digit.
734 quo_est is never low and is at most 2 high. */
735 unsigned HOST_WIDE_INT tmp;
737 num_hi_sig = i + den_hi_sig + 1;
738 work = num[num_hi_sig] * BASE + num[num_hi_sig - 1];
739 if (num[num_hi_sig] != den[den_hi_sig])
740 quo_est = work / den[den_hi_sig];
744 /* Refine quo_est so it's usually correct, and at most one high. */
745 tmp = work - quo_est * den[den_hi_sig];
747 && (den[den_hi_sig - 1] * quo_est
748 > (tmp * BASE + num[num_hi_sig - 2])))
751 /* Try QUO_EST as the quotient digit, by multiplying the
752 divisor by QUO_EST and subtracting from the remaining dividend.
753 Keep in mind that QUO_EST is the I - 1st digit. */
756 for (j = 0; j <= den_hi_sig; j++)
758 work = quo_est * den[j] + carry;
759 carry = HIGHPART (work);
760 work = num[i + j] - LOWPART (work);
761 num[i + j] = LOWPART (work);
762 carry += HIGHPART (work) != 0;
765 /* If quo_est was high by one, then num[i] went negative and
766 we need to correct things. */
767 if (num[num_hi_sig] < (HOST_WIDE_INT) carry)
770 carry = 0; /* add divisor back in */
771 for (j = 0; j <= den_hi_sig; j++)
773 work = num[i + j] + den[j] + carry;
774 carry = HIGHPART (work);
775 num[i + j] = LOWPART (work);
778 num [num_hi_sig] += carry;
781 /* Store the quotient digit. */
786 decode (quo, lquo, hquo);
789 /* If result is negative, make it so. */
791 neg_double (*lquo, *hquo, lquo, hquo);
793 /* Compute trial remainder: rem = num - (quo * den) */
794 mul_double (*lquo, *hquo, lden_orig, hden_orig, lrem, hrem);
795 neg_double (*lrem, *hrem, lrem, hrem);
796 add_double (lnum_orig, hnum_orig, *lrem, *hrem, lrem, hrem);
801 case TRUNC_MOD_EXPR: /* round toward zero */
802 case EXACT_DIV_EXPR: /* for this one, it shouldn't matter */
806 case FLOOR_MOD_EXPR: /* round toward negative infinity */
807 if (quo_neg && (*lrem != 0 || *hrem != 0)) /* ratio < 0 && rem != 0 */
810 add_double (*lquo, *hquo, (HOST_WIDE_INT) -1, (HOST_WIDE_INT) -1,
818 case CEIL_MOD_EXPR: /* round toward positive infinity */
819 if (!quo_neg && (*lrem != 0 || *hrem != 0)) /* ratio > 0 && rem != 0 */
821 add_double (*lquo, *hquo, (HOST_WIDE_INT) 1, (HOST_WIDE_INT) 0,
829 case ROUND_MOD_EXPR: /* round to closest integer */
831 unsigned HOST_WIDE_INT labs_rem = *lrem;
832 HOST_WIDE_INT habs_rem = *hrem;
833 unsigned HOST_WIDE_INT labs_den = lden, ltwice;
834 HOST_WIDE_INT habs_den = hden, htwice;
836 /* Get absolute values. */
838 neg_double (*lrem, *hrem, &labs_rem, &habs_rem);
840 neg_double (lden, hden, &labs_den, &habs_den);
842 /* If (2 * abs (lrem) >= abs (lden)), adjust the quotient. */
843 mul_double ((HOST_WIDE_INT) 2, (HOST_WIDE_INT) 0,
844 labs_rem, habs_rem, <wice, &htwice);
846 if (((unsigned HOST_WIDE_INT) habs_den
847 < (unsigned HOST_WIDE_INT) htwice)
848 || (((unsigned HOST_WIDE_INT) habs_den
849 == (unsigned HOST_WIDE_INT) htwice)
850 && (labs_den <= ltwice)))
854 add_double (*lquo, *hquo,
855 (HOST_WIDE_INT) -1, (HOST_WIDE_INT) -1, lquo, hquo);
858 add_double (*lquo, *hquo, (HOST_WIDE_INT) 1, (HOST_WIDE_INT) 0,
870 /* Compute true remainder: rem = num - (quo * den) */
871 mul_double (*lquo, *hquo, lden_orig, hden_orig, lrem, hrem);
872 neg_double (*lrem, *hrem, lrem, hrem);
873 add_double (lnum_orig, hnum_orig, *lrem, *hrem, lrem, hrem);
877 /* If ARG2 divides ARG1 with zero remainder, carries out the division
878 of type CODE and returns the quotient.
879 Otherwise returns NULL_TREE. */
882 div_if_zero_remainder (enum tree_code code, const_tree arg1, const_tree arg2)
884 unsigned HOST_WIDE_INT int1l, int2l;
885 HOST_WIDE_INT int1h, int2h;
886 unsigned HOST_WIDE_INT quol, reml;
887 HOST_WIDE_INT quoh, remh;
890 /* The sign of the division is according to operand two, that
891 does the correct thing for POINTER_PLUS_EXPR where we want
892 a signed division. */
893 uns = TYPE_UNSIGNED (TREE_TYPE (arg2));
894 if (TREE_CODE (TREE_TYPE (arg2)) == INTEGER_TYPE
895 && TYPE_IS_SIZETYPE (TREE_TYPE (arg2)))
898 int1l = TREE_INT_CST_LOW (arg1);
899 int1h = TREE_INT_CST_HIGH (arg1);
900 int2l = TREE_INT_CST_LOW (arg2);
901 int2h = TREE_INT_CST_HIGH (arg2);
903 div_and_round_double (code, uns, int1l, int1h, int2l, int2h,
904 &quol, &quoh, &reml, &remh);
905 if (remh != 0 || reml != 0)
908 return build_int_cst_wide (TREE_TYPE (arg1), quol, quoh);
911 /* This is nonzero if we should defer warnings about undefined
912 overflow. This facility exists because these warnings are a
913 special case. The code to estimate loop iterations does not want
914 to issue any warnings, since it works with expressions which do not
915 occur in user code. Various bits of cleanup code call fold(), but
916 only use the result if it has certain characteristics (e.g., is a
917 constant); that code only wants to issue a warning if the result is
920 static int fold_deferring_overflow_warnings;
922 /* If a warning about undefined overflow is deferred, this is the
923 warning. Note that this may cause us to turn two warnings into
924 one, but that is fine since it is sufficient to only give one
925 warning per expression. */
927 static const char* fold_deferred_overflow_warning;
929 /* If a warning about undefined overflow is deferred, this is the
930 level at which the warning should be emitted. */
932 static enum warn_strict_overflow_code fold_deferred_overflow_code;
934 /* Start deferring overflow warnings. We could use a stack here to
935 permit nested calls, but at present it is not necessary. */
938 fold_defer_overflow_warnings (void)
940 ++fold_deferring_overflow_warnings;
943 /* Stop deferring overflow warnings. If there is a pending warning,
944 and ISSUE is true, then issue the warning if appropriate. STMT is
945 the statement with which the warning should be associated (used for
946 location information); STMT may be NULL. CODE is the level of the
947 warning--a warn_strict_overflow_code value. This function will use
948 the smaller of CODE and the deferred code when deciding whether to
949 issue the warning. CODE may be zero to mean to always use the
953 fold_undefer_overflow_warnings (bool issue, const_gimple stmt, int code)
958 gcc_assert (fold_deferring_overflow_warnings > 0);
959 --fold_deferring_overflow_warnings;
960 if (fold_deferring_overflow_warnings > 0)
962 if (fold_deferred_overflow_warning != NULL
964 && code < (int) fold_deferred_overflow_code)
965 fold_deferred_overflow_code = (enum warn_strict_overflow_code) code;
969 warnmsg = fold_deferred_overflow_warning;
970 fold_deferred_overflow_warning = NULL;
972 if (!issue || warnmsg == NULL)
975 if (gimple_no_warning_p (stmt))
978 /* Use the smallest code level when deciding to issue the
980 if (code == 0 || code > (int) fold_deferred_overflow_code)
981 code = fold_deferred_overflow_code;
983 if (!issue_strict_overflow_warning (code))
987 locus = input_location;
989 locus = gimple_location (stmt);
990 warning_at (locus, OPT_Wstrict_overflow, "%s", warnmsg);
993 /* Stop deferring overflow warnings, ignoring any deferred
997 fold_undefer_and_ignore_overflow_warnings (void)
999 fold_undefer_overflow_warnings (false, NULL, 0);
1002 /* Whether we are deferring overflow warnings. */
1005 fold_deferring_overflow_warnings_p (void)
1007 return fold_deferring_overflow_warnings > 0;
1010 /* This is called when we fold something based on the fact that signed
1011 overflow is undefined. */
1014 fold_overflow_warning (const char* gmsgid, enum warn_strict_overflow_code wc)
1016 if (fold_deferring_overflow_warnings > 0)
1018 if (fold_deferred_overflow_warning == NULL
1019 || wc < fold_deferred_overflow_code)
1021 fold_deferred_overflow_warning = gmsgid;
1022 fold_deferred_overflow_code = wc;
1025 else if (issue_strict_overflow_warning (wc))
1026 warning (OPT_Wstrict_overflow, gmsgid);
1029 /* Return true if the built-in mathematical function specified by CODE
1030 is odd, i.e. -f(x) == f(-x). */
1033 negate_mathfn_p (enum built_in_function code)
1037 CASE_FLT_FN (BUILT_IN_ASIN):
1038 CASE_FLT_FN (BUILT_IN_ASINH):
1039 CASE_FLT_FN (BUILT_IN_ATAN):
1040 CASE_FLT_FN (BUILT_IN_ATANH):
1041 CASE_FLT_FN (BUILT_IN_CASIN):
1042 CASE_FLT_FN (BUILT_IN_CASINH):
1043 CASE_FLT_FN (BUILT_IN_CATAN):
1044 CASE_FLT_FN (BUILT_IN_CATANH):
1045 CASE_FLT_FN (BUILT_IN_CBRT):
1046 CASE_FLT_FN (BUILT_IN_CPROJ):
1047 CASE_FLT_FN (BUILT_IN_CSIN):
1048 CASE_FLT_FN (BUILT_IN_CSINH):
1049 CASE_FLT_FN (BUILT_IN_CTAN):
1050 CASE_FLT_FN (BUILT_IN_CTANH):
1051 CASE_FLT_FN (BUILT_IN_ERF):
1052 CASE_FLT_FN (BUILT_IN_LLROUND):
1053 CASE_FLT_FN (BUILT_IN_LROUND):
1054 CASE_FLT_FN (BUILT_IN_ROUND):
1055 CASE_FLT_FN (BUILT_IN_SIN):
1056 CASE_FLT_FN (BUILT_IN_SINH):
1057 CASE_FLT_FN (BUILT_IN_TAN):
1058 CASE_FLT_FN (BUILT_IN_TANH):
1059 CASE_FLT_FN (BUILT_IN_TRUNC):
1062 CASE_FLT_FN (BUILT_IN_LLRINT):
1063 CASE_FLT_FN (BUILT_IN_LRINT):
1064 CASE_FLT_FN (BUILT_IN_NEARBYINT):
1065 CASE_FLT_FN (BUILT_IN_RINT):
1066 return !flag_rounding_math;
1074 /* Check whether we may negate an integer constant T without causing
1078 may_negate_without_overflow_p (const_tree t)
1080 unsigned HOST_WIDE_INT val;
1084 gcc_assert (TREE_CODE (t) == INTEGER_CST);
1086 type = TREE_TYPE (t);
1087 if (TYPE_UNSIGNED (type))
1090 prec = TYPE_PRECISION (type);
1091 if (prec > HOST_BITS_PER_WIDE_INT)
1093 if (TREE_INT_CST_LOW (t) != 0)
1095 prec -= HOST_BITS_PER_WIDE_INT;
1096 val = TREE_INT_CST_HIGH (t);
1099 val = TREE_INT_CST_LOW (t);
1100 if (prec < HOST_BITS_PER_WIDE_INT)
1101 val &= ((unsigned HOST_WIDE_INT) 1 << prec) - 1;
1102 return val != ((unsigned HOST_WIDE_INT) 1 << (prec - 1));
1105 /* Determine whether an expression T can be cheaply negated using
1106 the function negate_expr without introducing undefined overflow. */
1109 negate_expr_p (tree t)
1116 type = TREE_TYPE (t);
1118 STRIP_SIGN_NOPS (t);
1119 switch (TREE_CODE (t))
1122 if (TYPE_OVERFLOW_WRAPS (type))
1125 /* Check that -CST will not overflow type. */
1126 return may_negate_without_overflow_p (t);
1128 return (INTEGRAL_TYPE_P (type)
1129 && TYPE_OVERFLOW_WRAPS (type));
1136 /* We want to canonicalize to positive real constants. Pretend
1137 that only negative ones can be easily negated. */
1138 return REAL_VALUE_NEGATIVE (TREE_REAL_CST (t));
1141 return negate_expr_p (TREE_REALPART (t))
1142 && negate_expr_p (TREE_IMAGPART (t));
1145 return negate_expr_p (TREE_OPERAND (t, 0))
1146 && negate_expr_p (TREE_OPERAND (t, 1));
1149 return negate_expr_p (TREE_OPERAND (t, 0));
1152 if (HONOR_SIGN_DEPENDENT_ROUNDING (TYPE_MODE (type))
1153 || HONOR_SIGNED_ZEROS (TYPE_MODE (type)))
1155 /* -(A + B) -> (-B) - A. */
1156 if (negate_expr_p (TREE_OPERAND (t, 1))
1157 && reorder_operands_p (TREE_OPERAND (t, 0),
1158 TREE_OPERAND (t, 1)))
1160 /* -(A + B) -> (-A) - B. */
1161 return negate_expr_p (TREE_OPERAND (t, 0));
1164 /* We can't turn -(A-B) into B-A when we honor signed zeros. */
1165 return !HONOR_SIGN_DEPENDENT_ROUNDING (TYPE_MODE (type))
1166 && !HONOR_SIGNED_ZEROS (TYPE_MODE (type))
1167 && reorder_operands_p (TREE_OPERAND (t, 0),
1168 TREE_OPERAND (t, 1));
1171 if (TYPE_UNSIGNED (TREE_TYPE (t)))
1177 if (! HONOR_SIGN_DEPENDENT_ROUNDING (TYPE_MODE (TREE_TYPE (t))))
1178 return negate_expr_p (TREE_OPERAND (t, 1))
1179 || negate_expr_p (TREE_OPERAND (t, 0));
1182 case TRUNC_DIV_EXPR:
1183 case ROUND_DIV_EXPR:
1184 case FLOOR_DIV_EXPR:
1186 case EXACT_DIV_EXPR:
1187 /* In general we can't negate A / B, because if A is INT_MIN and
1188 B is 1, we may turn this into INT_MIN / -1 which is undefined
1189 and actually traps on some architectures. But if overflow is
1190 undefined, we can negate, because - (INT_MIN / 1) is an
1192 if (INTEGRAL_TYPE_P (TREE_TYPE (t))
1193 && !TYPE_OVERFLOW_UNDEFINED (TREE_TYPE (t)))
1195 return negate_expr_p (TREE_OPERAND (t, 1))
1196 || negate_expr_p (TREE_OPERAND (t, 0));
1199 /* Negate -((double)float) as (double)(-float). */
1200 if (TREE_CODE (type) == REAL_TYPE)
1202 tree tem = strip_float_extensions (t);
1204 return negate_expr_p (tem);
1209 /* Negate -f(x) as f(-x). */
1210 if (negate_mathfn_p (builtin_mathfn_code (t)))
1211 return negate_expr_p (CALL_EXPR_ARG (t, 0));
1215 /* Optimize -((int)x >> 31) into (unsigned)x >> 31. */
1216 if (TREE_CODE (TREE_OPERAND (t, 1)) == INTEGER_CST)
1218 tree op1 = TREE_OPERAND (t, 1);
1219 if (TREE_INT_CST_HIGH (op1) == 0
1220 && (unsigned HOST_WIDE_INT) (TYPE_PRECISION (type) - 1)
1221 == TREE_INT_CST_LOW (op1))
1232 /* Given T, an expression, return a folded tree for -T or NULL_TREE, if no
1233 simplification is possible.
1234 If negate_expr_p would return true for T, NULL_TREE will never be
1238 fold_negate_expr (location_t loc, tree t)
1240 tree type = TREE_TYPE (t);
1243 switch (TREE_CODE (t))
1245 /* Convert - (~A) to A + 1. */
1247 if (INTEGRAL_TYPE_P (type))
1248 return fold_build2_loc (loc, PLUS_EXPR, type, TREE_OPERAND (t, 0),
1249 build_int_cst (type, 1));
1253 tem = fold_negate_const (t, type);
1254 if (TREE_OVERFLOW (tem) == TREE_OVERFLOW (t)
1255 || !TYPE_OVERFLOW_TRAPS (type))
1260 tem = fold_negate_const (t, type);
1261 /* Two's complement FP formats, such as c4x, may overflow. */
1262 if (!TREE_OVERFLOW (tem) || !flag_trapping_math)
1267 tem = fold_negate_const (t, type);
1272 tree rpart = negate_expr (TREE_REALPART (t));
1273 tree ipart = negate_expr (TREE_IMAGPART (t));
1275 if ((TREE_CODE (rpart) == REAL_CST
1276 && TREE_CODE (ipart) == REAL_CST)
1277 || (TREE_CODE (rpart) == INTEGER_CST
1278 && TREE_CODE (ipart) == INTEGER_CST))
1279 return build_complex (type, rpart, ipart);
1284 if (negate_expr_p (t))
1285 return fold_build2_loc (loc, COMPLEX_EXPR, type,
1286 fold_negate_expr (loc, TREE_OPERAND (t, 0)),
1287 fold_negate_expr (loc, TREE_OPERAND (t, 1)));
1291 if (negate_expr_p (t))
1292 return fold_build1_loc (loc, CONJ_EXPR, type,
1293 fold_negate_expr (loc, TREE_OPERAND (t, 0)));
1297 return TREE_OPERAND (t, 0);
1300 if (!HONOR_SIGN_DEPENDENT_ROUNDING (TYPE_MODE (type))
1301 && !HONOR_SIGNED_ZEROS (TYPE_MODE (type)))
1303 /* -(A + B) -> (-B) - A. */
1304 if (negate_expr_p (TREE_OPERAND (t, 1))
1305 && reorder_operands_p (TREE_OPERAND (t, 0),
1306 TREE_OPERAND (t, 1)))
1308 tem = negate_expr (TREE_OPERAND (t, 1));
1309 return fold_build2_loc (loc, MINUS_EXPR, type,
1310 tem, TREE_OPERAND (t, 0));
1313 /* -(A + B) -> (-A) - B. */
1314 if (negate_expr_p (TREE_OPERAND (t, 0)))
1316 tem = negate_expr (TREE_OPERAND (t, 0));
1317 return fold_build2_loc (loc, MINUS_EXPR, type,
1318 tem, TREE_OPERAND (t, 1));
1324 /* - (A - B) -> B - A */
1325 if (!HONOR_SIGN_DEPENDENT_ROUNDING (TYPE_MODE (type))
1326 && !HONOR_SIGNED_ZEROS (TYPE_MODE (type))
1327 && reorder_operands_p (TREE_OPERAND (t, 0), TREE_OPERAND (t, 1)))
1328 return fold_build2_loc (loc, MINUS_EXPR, type,
1329 TREE_OPERAND (t, 1), TREE_OPERAND (t, 0));
1333 if (TYPE_UNSIGNED (type))
1339 if (! HONOR_SIGN_DEPENDENT_ROUNDING (TYPE_MODE (type)))
1341 tem = TREE_OPERAND (t, 1);
1342 if (negate_expr_p (tem))
1343 return fold_build2_loc (loc, TREE_CODE (t), type,
1344 TREE_OPERAND (t, 0), negate_expr (tem));
1345 tem = TREE_OPERAND (t, 0);
1346 if (negate_expr_p (tem))
1347 return fold_build2_loc (loc, TREE_CODE (t), type,
1348 negate_expr (tem), TREE_OPERAND (t, 1));
1352 case TRUNC_DIV_EXPR:
1353 case ROUND_DIV_EXPR:
1354 case FLOOR_DIV_EXPR:
1356 case EXACT_DIV_EXPR:
1357 /* In general we can't negate A / B, because if A is INT_MIN and
1358 B is 1, we may turn this into INT_MIN / -1 which is undefined
1359 and actually traps on some architectures. But if overflow is
1360 undefined, we can negate, because - (INT_MIN / 1) is an
1362 if (!INTEGRAL_TYPE_P (type) || TYPE_OVERFLOW_UNDEFINED (type))
1364 const char * const warnmsg = G_("assuming signed overflow does not "
1365 "occur when negating a division");
1366 tem = TREE_OPERAND (t, 1);
1367 if (negate_expr_p (tem))
1369 if (INTEGRAL_TYPE_P (type)
1370 && (TREE_CODE (tem) != INTEGER_CST
1371 || integer_onep (tem)))
1372 fold_overflow_warning (warnmsg, WARN_STRICT_OVERFLOW_MISC);
1373 return fold_build2_loc (loc, TREE_CODE (t), type,
1374 TREE_OPERAND (t, 0), negate_expr (tem));
1376 tem = TREE_OPERAND (t, 0);
1377 if (negate_expr_p (tem))
1379 if (INTEGRAL_TYPE_P (type)
1380 && (TREE_CODE (tem) != INTEGER_CST
1381 || tree_int_cst_equal (tem, TYPE_MIN_VALUE (type))))
1382 fold_overflow_warning (warnmsg, WARN_STRICT_OVERFLOW_MISC);
1383 return fold_build2_loc (loc, TREE_CODE (t), type,
1384 negate_expr (tem), TREE_OPERAND (t, 1));
1390 /* Convert -((double)float) into (double)(-float). */
1391 if (TREE_CODE (type) == REAL_TYPE)
1393 tem = strip_float_extensions (t);
1394 if (tem != t && negate_expr_p (tem))
1395 return fold_convert_loc (loc, type, negate_expr (tem));
1400 /* Negate -f(x) as f(-x). */
1401 if (negate_mathfn_p (builtin_mathfn_code (t))
1402 && negate_expr_p (CALL_EXPR_ARG (t, 0)))
1406 fndecl = get_callee_fndecl (t);
1407 arg = negate_expr (CALL_EXPR_ARG (t, 0));
1408 return build_call_expr_loc (loc, fndecl, 1, arg);
1413 /* Optimize -((int)x >> 31) into (unsigned)x >> 31. */
1414 if (TREE_CODE (TREE_OPERAND (t, 1)) == INTEGER_CST)
1416 tree op1 = TREE_OPERAND (t, 1);
1417 if (TREE_INT_CST_HIGH (op1) == 0
1418 && (unsigned HOST_WIDE_INT) (TYPE_PRECISION (type) - 1)
1419 == TREE_INT_CST_LOW (op1))
1421 tree ntype = TYPE_UNSIGNED (type)
1422 ? signed_type_for (type)
1423 : unsigned_type_for (type);
1424 tree temp = fold_convert_loc (loc, ntype, TREE_OPERAND (t, 0));
1425 temp = fold_build2_loc (loc, RSHIFT_EXPR, ntype, temp, op1);
1426 return fold_convert_loc (loc, type, temp);
1438 /* Like fold_negate_expr, but return a NEGATE_EXPR tree, if T can not be
1439 negated in a simpler way. Also allow for T to be NULL_TREE, in which case
1440 return NULL_TREE. */
1443 negate_expr (tree t)
1451 loc = EXPR_LOCATION (t);
1452 type = TREE_TYPE (t);
1453 STRIP_SIGN_NOPS (t);
1455 tem = fold_negate_expr (loc, t);
1458 tem = build1 (NEGATE_EXPR, TREE_TYPE (t), t);
1459 SET_EXPR_LOCATION (tem, loc);
1461 return fold_convert_loc (loc, type, tem);
1464 /* Split a tree IN into a constant, literal and variable parts that could be
1465 combined with CODE to make IN. "constant" means an expression with
1466 TREE_CONSTANT but that isn't an actual constant. CODE must be a
1467 commutative arithmetic operation. Store the constant part into *CONP,
1468 the literal in *LITP and return the variable part. If a part isn't
1469 present, set it to null. If the tree does not decompose in this way,
1470 return the entire tree as the variable part and the other parts as null.
1472 If CODE is PLUS_EXPR we also split trees that use MINUS_EXPR. In that
1473 case, we negate an operand that was subtracted. Except if it is a
1474 literal for which we use *MINUS_LITP instead.
1476 If NEGATE_P is true, we are negating all of IN, again except a literal
1477 for which we use *MINUS_LITP instead.
1479 If IN is itself a literal or constant, return it as appropriate.
1481 Note that we do not guarantee that any of the three values will be the
1482 same type as IN, but they will have the same signedness and mode. */
1485 split_tree (tree in, enum tree_code code, tree *conp, tree *litp,
1486 tree *minus_litp, int negate_p)
1494 /* Strip any conversions that don't change the machine mode or signedness. */
1495 STRIP_SIGN_NOPS (in);
1497 if (TREE_CODE (in) == INTEGER_CST || TREE_CODE (in) == REAL_CST
1498 || TREE_CODE (in) == FIXED_CST)
1500 else if (TREE_CODE (in) == code
1501 || ((! FLOAT_TYPE_P (TREE_TYPE (in)) || flag_associative_math)
1502 && ! SAT_FIXED_POINT_TYPE_P (TREE_TYPE (in))
1503 /* We can associate addition and subtraction together (even
1504 though the C standard doesn't say so) for integers because
1505 the value is not affected. For reals, the value might be
1506 affected, so we can't. */
1507 && ((code == PLUS_EXPR && TREE_CODE (in) == MINUS_EXPR)
1508 || (code == MINUS_EXPR && TREE_CODE (in) == PLUS_EXPR))))
1510 tree op0 = TREE_OPERAND (in, 0);
1511 tree op1 = TREE_OPERAND (in, 1);
1512 int neg1_p = TREE_CODE (in) == MINUS_EXPR;
1513 int neg_litp_p = 0, neg_conp_p = 0, neg_var_p = 0;
1515 /* First see if either of the operands is a literal, then a constant. */
1516 if (TREE_CODE (op0) == INTEGER_CST || TREE_CODE (op0) == REAL_CST
1517 || TREE_CODE (op0) == FIXED_CST)
1518 *litp = op0, op0 = 0;
1519 else if (TREE_CODE (op1) == INTEGER_CST || TREE_CODE (op1) == REAL_CST
1520 || TREE_CODE (op1) == FIXED_CST)
1521 *litp = op1, neg_litp_p = neg1_p, op1 = 0;
1523 if (op0 != 0 && TREE_CONSTANT (op0))
1524 *conp = op0, op0 = 0;
1525 else if (op1 != 0 && TREE_CONSTANT (op1))
1526 *conp = op1, neg_conp_p = neg1_p, op1 = 0;
1528 /* If we haven't dealt with either operand, this is not a case we can
1529 decompose. Otherwise, VAR is either of the ones remaining, if any. */
1530 if (op0 != 0 && op1 != 0)
1535 var = op1, neg_var_p = neg1_p;
1537 /* Now do any needed negations. */
1539 *minus_litp = *litp, *litp = 0;
1541 *conp = negate_expr (*conp);
1543 var = negate_expr (var);
1545 else if (TREE_CONSTANT (in))
1553 *minus_litp = *litp, *litp = 0;
1554 else if (*minus_litp)
1555 *litp = *minus_litp, *minus_litp = 0;
1556 *conp = negate_expr (*conp);
1557 var = negate_expr (var);
1563 /* Re-associate trees split by the above function. T1 and T2 are
1564 either expressions to associate or null. Return the new
1565 expression, if any. LOC is the location of the new expression. If
1566 we build an operation, do it in TYPE and with CODE. */
1569 associate_trees (location_t loc, tree t1, tree t2, enum tree_code code, tree type)
1578 /* If either input is CODE, a PLUS_EXPR, or a MINUS_EXPR, don't
1579 try to fold this since we will have infinite recursion. But do
1580 deal with any NEGATE_EXPRs. */
1581 if (TREE_CODE (t1) == code || TREE_CODE (t2) == code
1582 || TREE_CODE (t1) == MINUS_EXPR || TREE_CODE (t2) == MINUS_EXPR)
1584 if (code == PLUS_EXPR)
1586 if (TREE_CODE (t1) == NEGATE_EXPR)
1587 tem = build2 (MINUS_EXPR, type, fold_convert_loc (loc, type, t2),
1588 fold_convert_loc (loc, type, TREE_OPERAND (t1, 0)));
1589 else if (TREE_CODE (t2) == NEGATE_EXPR)
1590 tem = build2 (MINUS_EXPR, type, fold_convert_loc (loc, type, t1),
1591 fold_convert_loc (loc, type, TREE_OPERAND (t2, 0)));
1592 else if (integer_zerop (t2))
1593 return fold_convert_loc (loc, type, t1);
1595 else if (code == MINUS_EXPR)
1597 if (integer_zerop (t2))
1598 return fold_convert_loc (loc, type, t1);
1601 tem = build2 (code, type, fold_convert_loc (loc, type, t1),
1602 fold_convert_loc (loc, type, t2));
1603 goto associate_trees_exit;
1606 return fold_build2_loc (loc, code, type, fold_convert_loc (loc, type, t1),
1607 fold_convert_loc (loc, type, t2));
1608 associate_trees_exit:
1609 protected_set_expr_location (tem, loc);
1613 /* Check whether TYPE1 and TYPE2 are equivalent integer types, suitable
1614 for use in int_const_binop, size_binop and size_diffop. */
1617 int_binop_types_match_p (enum tree_code code, const_tree type1, const_tree type2)
1619 if (TREE_CODE (type1) != INTEGER_TYPE && !POINTER_TYPE_P (type1))
1621 if (TREE_CODE (type2) != INTEGER_TYPE && !POINTER_TYPE_P (type2))
1636 return TYPE_UNSIGNED (type1) == TYPE_UNSIGNED (type2)
1637 && TYPE_PRECISION (type1) == TYPE_PRECISION (type2)
1638 && TYPE_MODE (type1) == TYPE_MODE (type2);
1642 /* Combine two integer constants ARG1 and ARG2 under operation CODE
1643 to produce a new constant. Return NULL_TREE if we don't know how
1644 to evaluate CODE at compile-time.
1646 If NOTRUNC is nonzero, do not truncate the result to fit the data type. */
1649 int_const_binop (enum tree_code code, const_tree arg1, const_tree arg2, int notrunc)
1651 unsigned HOST_WIDE_INT int1l, int2l;
1652 HOST_WIDE_INT int1h, int2h;
1653 unsigned HOST_WIDE_INT low;
1655 unsigned HOST_WIDE_INT garbagel;
1656 HOST_WIDE_INT garbageh;
1658 tree type = TREE_TYPE (arg1);
1659 int uns = TYPE_UNSIGNED (type);
1661 = (TREE_CODE (type) == INTEGER_TYPE && TYPE_IS_SIZETYPE (type));
1664 int1l = TREE_INT_CST_LOW (arg1);
1665 int1h = TREE_INT_CST_HIGH (arg1);
1666 int2l = TREE_INT_CST_LOW (arg2);
1667 int2h = TREE_INT_CST_HIGH (arg2);
1672 low = int1l | int2l, hi = int1h | int2h;
1676 low = int1l ^ int2l, hi = int1h ^ int2h;
1680 low = int1l & int2l, hi = int1h & int2h;
1686 /* It's unclear from the C standard whether shifts can overflow.
1687 The following code ignores overflow; perhaps a C standard
1688 interpretation ruling is needed. */
1689 lshift_double (int1l, int1h, int2l, TYPE_PRECISION (type),
1696 lrotate_double (int1l, int1h, int2l, TYPE_PRECISION (type),
1701 overflow = add_double (int1l, int1h, int2l, int2h, &low, &hi);
1705 neg_double (int2l, int2h, &low, &hi);
1706 add_double (int1l, int1h, low, hi, &low, &hi);
1707 overflow = OVERFLOW_SUM_SIGN (hi, int2h, int1h);
1711 overflow = mul_double (int1l, int1h, int2l, int2h, &low, &hi);
1714 case TRUNC_DIV_EXPR:
1715 case FLOOR_DIV_EXPR: case CEIL_DIV_EXPR:
1716 case EXACT_DIV_EXPR:
1717 /* This is a shortcut for a common special case. */
1718 if (int2h == 0 && (HOST_WIDE_INT) int2l > 0
1719 && !TREE_OVERFLOW (arg1)
1720 && !TREE_OVERFLOW (arg2)
1721 && int1h == 0 && (HOST_WIDE_INT) int1l >= 0)
1723 if (code == CEIL_DIV_EXPR)
1726 low = int1l / int2l, hi = 0;
1730 /* ... fall through ... */
1732 case ROUND_DIV_EXPR:
1733 if (int2h == 0 && int2l == 0)
1735 if (int2h == 0 && int2l == 1)
1737 low = int1l, hi = int1h;
1740 if (int1l == int2l && int1h == int2h
1741 && ! (int1l == 0 && int1h == 0))
1746 overflow = div_and_round_double (code, uns, int1l, int1h, int2l, int2h,
1747 &low, &hi, &garbagel, &garbageh);
1750 case TRUNC_MOD_EXPR:
1751 case FLOOR_MOD_EXPR: case CEIL_MOD_EXPR:
1752 /* This is a shortcut for a common special case. */
1753 if (int2h == 0 && (HOST_WIDE_INT) int2l > 0
1754 && !TREE_OVERFLOW (arg1)
1755 && !TREE_OVERFLOW (arg2)
1756 && int1h == 0 && (HOST_WIDE_INT) int1l >= 0)
1758 if (code == CEIL_MOD_EXPR)
1760 low = int1l % int2l, hi = 0;
1764 /* ... fall through ... */
1766 case ROUND_MOD_EXPR:
1767 if (int2h == 0 && int2l == 0)
1769 overflow = div_and_round_double (code, uns,
1770 int1l, int1h, int2l, int2h,
1771 &garbagel, &garbageh, &low, &hi);
1777 low = (((unsigned HOST_WIDE_INT) int1h
1778 < (unsigned HOST_WIDE_INT) int2h)
1779 || (((unsigned HOST_WIDE_INT) int1h
1780 == (unsigned HOST_WIDE_INT) int2h)
1783 low = (int1h < int2h
1784 || (int1h == int2h && int1l < int2l));
1786 if (low == (code == MIN_EXPR))
1787 low = int1l, hi = int1h;
1789 low = int2l, hi = int2h;
1798 t = build_int_cst_wide (TREE_TYPE (arg1), low, hi);
1800 /* Propagate overflow flags ourselves. */
1801 if (((!uns || is_sizetype) && overflow)
1802 | TREE_OVERFLOW (arg1) | TREE_OVERFLOW (arg2))
1805 TREE_OVERFLOW (t) = 1;
1809 t = force_fit_type_double (TREE_TYPE (arg1), low, hi, 1,
1810 ((!uns || is_sizetype) && overflow)
1811 | TREE_OVERFLOW (arg1) | TREE_OVERFLOW (arg2));
1816 /* Combine two constants ARG1 and ARG2 under operation CODE to produce a new
1817 constant. We assume ARG1 and ARG2 have the same data type, or at least
1818 are the same kind of constant and the same machine mode. Return zero if
1819 combining the constants is not allowed in the current operating mode.
1821 If NOTRUNC is nonzero, do not truncate the result to fit the data type. */
1824 const_binop (enum tree_code code, tree arg1, tree arg2, int notrunc)
1826 /* Sanity check for the recursive cases. */
1833 if (TREE_CODE (arg1) == INTEGER_CST)
1834 return int_const_binop (code, arg1, arg2, notrunc);
1836 if (TREE_CODE (arg1) == REAL_CST)
1838 enum machine_mode mode;
1841 REAL_VALUE_TYPE value;
1842 REAL_VALUE_TYPE result;
1846 /* The following codes are handled by real_arithmetic. */
1861 d1 = TREE_REAL_CST (arg1);
1862 d2 = TREE_REAL_CST (arg2);
1864 type = TREE_TYPE (arg1);
1865 mode = TYPE_MODE (type);
1867 /* Don't perform operation if we honor signaling NaNs and
1868 either operand is a NaN. */
1869 if (HONOR_SNANS (mode)
1870 && (REAL_VALUE_ISNAN (d1) || REAL_VALUE_ISNAN (d2)))
1873 /* Don't perform operation if it would raise a division
1874 by zero exception. */
1875 if (code == RDIV_EXPR
1876 && REAL_VALUES_EQUAL (d2, dconst0)
1877 && (flag_trapping_math || ! MODE_HAS_INFINITIES (mode)))
1880 /* If either operand is a NaN, just return it. Otherwise, set up
1881 for floating-point trap; we return an overflow. */
1882 if (REAL_VALUE_ISNAN (d1))
1884 else if (REAL_VALUE_ISNAN (d2))
1887 inexact = real_arithmetic (&value, code, &d1, &d2);
1888 real_convert (&result, mode, &value);
1890 /* Don't constant fold this floating point operation if
1891 the result has overflowed and flag_trapping_math. */
1892 if (flag_trapping_math
1893 && MODE_HAS_INFINITIES (mode)
1894 && REAL_VALUE_ISINF (result)
1895 && !REAL_VALUE_ISINF (d1)
1896 && !REAL_VALUE_ISINF (d2))
1899 /* Don't constant fold this floating point operation if the
1900 result may dependent upon the run-time rounding mode and
1901 flag_rounding_math is set, or if GCC's software emulation
1902 is unable to accurately represent the result. */
1903 if ((flag_rounding_math
1904 || (MODE_COMPOSITE_P (mode) && !flag_unsafe_math_optimizations))
1905 && (inexact || !real_identical (&result, &value)))
1908 t = build_real (type, result);
1910 TREE_OVERFLOW (t) = TREE_OVERFLOW (arg1) | TREE_OVERFLOW (arg2);
1914 if (TREE_CODE (arg1) == FIXED_CST)
1916 FIXED_VALUE_TYPE f1;
1917 FIXED_VALUE_TYPE f2;
1918 FIXED_VALUE_TYPE result;
1923 /* The following codes are handled by fixed_arithmetic. */
1929 case TRUNC_DIV_EXPR:
1930 f2 = TREE_FIXED_CST (arg2);
1935 f2.data.high = TREE_INT_CST_HIGH (arg2);
1936 f2.data.low = TREE_INT_CST_LOW (arg2);
1944 f1 = TREE_FIXED_CST (arg1);
1945 type = TREE_TYPE (arg1);
1946 sat_p = TYPE_SATURATING (type);
1947 overflow_p = fixed_arithmetic (&result, code, &f1, &f2, sat_p);
1948 t = build_fixed (type, result);
1949 /* Propagate overflow flags. */
1950 if (overflow_p | TREE_OVERFLOW (arg1) | TREE_OVERFLOW (arg2))
1951 TREE_OVERFLOW (t) = 1;
1955 if (TREE_CODE (arg1) == COMPLEX_CST)
1957 tree type = TREE_TYPE (arg1);
1958 tree r1 = TREE_REALPART (arg1);
1959 tree i1 = TREE_IMAGPART (arg1);
1960 tree r2 = TREE_REALPART (arg2);
1961 tree i2 = TREE_IMAGPART (arg2);
1968 real = const_binop (code, r1, r2, notrunc);
1969 imag = const_binop (code, i1, i2, notrunc);
1973 if (COMPLEX_FLOAT_TYPE_P (type))
1974 return do_mpc_arg2 (arg1, arg2, type,
1975 /* do_nonfinite= */ folding_initializer,
1978 real = const_binop (MINUS_EXPR,
1979 const_binop (MULT_EXPR, r1, r2, notrunc),
1980 const_binop (MULT_EXPR, i1, i2, notrunc),
1982 imag = const_binop (PLUS_EXPR,
1983 const_binop (MULT_EXPR, r1, i2, notrunc),
1984 const_binop (MULT_EXPR, i1, r2, notrunc),
1989 if (COMPLEX_FLOAT_TYPE_P (type))
1990 return do_mpc_arg2 (arg1, arg2, type,
1991 /* do_nonfinite= */ folding_initializer,
1994 case TRUNC_DIV_EXPR:
1996 case FLOOR_DIV_EXPR:
1997 case ROUND_DIV_EXPR:
1998 if (flag_complex_method == 0)
2000 /* Keep this algorithm in sync with
2001 tree-complex.c:expand_complex_div_straight().
2003 Expand complex division to scalars, straightforward algorithm.
2004 a / b = ((ar*br + ai*bi)/t) + i((ai*br - ar*bi)/t)
2008 = const_binop (PLUS_EXPR,
2009 const_binop (MULT_EXPR, r2, r2, notrunc),
2010 const_binop (MULT_EXPR, i2, i2, notrunc),
2013 = const_binop (PLUS_EXPR,
2014 const_binop (MULT_EXPR, r1, r2, notrunc),
2015 const_binop (MULT_EXPR, i1, i2, notrunc),
2018 = const_binop (MINUS_EXPR,
2019 const_binop (MULT_EXPR, i1, r2, notrunc),
2020 const_binop (MULT_EXPR, r1, i2, notrunc),
2023 real = const_binop (code, t1, magsquared, notrunc);
2024 imag = const_binop (code, t2, magsquared, notrunc);
2028 /* Keep this algorithm in sync with
2029 tree-complex.c:expand_complex_div_wide().
2031 Expand complex division to scalars, modified algorithm to minimize
2032 overflow with wide input ranges. */
2033 tree compare = fold_build2 (LT_EXPR, boolean_type_node,
2034 fold_abs_const (r2, TREE_TYPE (type)),
2035 fold_abs_const (i2, TREE_TYPE (type)));
2037 if (integer_nonzerop (compare))
2039 /* In the TRUE branch, we compute
2041 div = (br * ratio) + bi;
2042 tr = (ar * ratio) + ai;
2043 ti = (ai * ratio) - ar;
2046 tree ratio = const_binop (code, r2, i2, notrunc);
2047 tree div = const_binop (PLUS_EXPR, i2,
2048 const_binop (MULT_EXPR, r2, ratio,
2051 real = const_binop (MULT_EXPR, r1, ratio, notrunc);
2052 real = const_binop (PLUS_EXPR, real, i1, notrunc);
2053 real = const_binop (code, real, div, notrunc);
2055 imag = const_binop (MULT_EXPR, i1, ratio, notrunc);
2056 imag = const_binop (MINUS_EXPR, imag, r1, notrunc);
2057 imag = const_binop (code, imag, div, notrunc);
2061 /* In the FALSE branch, we compute
2063 divisor = (d * ratio) + c;
2064 tr = (b * ratio) + a;
2065 ti = b - (a * ratio);
2068 tree ratio = const_binop (code, i2, r2, notrunc);
2069 tree div = const_binop (PLUS_EXPR, r2,
2070 const_binop (MULT_EXPR, i2, ratio,
2074 real = const_binop (MULT_EXPR, i1, ratio, notrunc);
2075 real = const_binop (PLUS_EXPR, real, r1, notrunc);
2076 real = const_binop (code, real, div, notrunc);
2078 imag = const_binop (MULT_EXPR, r1, ratio, notrunc);
2079 imag = const_binop (MINUS_EXPR, i1, imag, notrunc);
2080 imag = const_binop (code, imag, div, notrunc);
2090 return build_complex (type, real, imag);
2093 if (TREE_CODE (arg1) == VECTOR_CST)
2095 tree type = TREE_TYPE(arg1);
2096 int count = TYPE_VECTOR_SUBPARTS (type), i;
2097 tree elements1, elements2, list = NULL_TREE;
2099 if(TREE_CODE(arg2) != VECTOR_CST)
2102 elements1 = TREE_VECTOR_CST_ELTS (arg1);
2103 elements2 = TREE_VECTOR_CST_ELTS (arg2);
2105 for (i = 0; i < count; i++)
2107 tree elem1, elem2, elem;
2109 /* The trailing elements can be empty and should be treated as 0 */
2111 elem1 = fold_convert_const (NOP_EXPR, TREE_TYPE (type), integer_zero_node);
2114 elem1 = TREE_VALUE(elements1);
2115 elements1 = TREE_CHAIN (elements1);
2119 elem2 = fold_convert_const (NOP_EXPR, TREE_TYPE (type), integer_zero_node);
2122 elem2 = TREE_VALUE(elements2);
2123 elements2 = TREE_CHAIN (elements2);
2126 elem = const_binop (code, elem1, elem2, notrunc);
2128 /* It is possible that const_binop cannot handle the given
2129 code and return NULL_TREE */
2130 if(elem == NULL_TREE)
2133 list = tree_cons (NULL_TREE, elem, list);
2135 return build_vector(type, nreverse(list));
2140 /* Create a size type INT_CST node with NUMBER sign extended. KIND
2141 indicates which particular sizetype to create. */
2144 size_int_kind (HOST_WIDE_INT number, enum size_type_kind kind)
2146 return build_int_cst (sizetype_tab[(int) kind], number);
2149 /* Combine operands OP1 and OP2 with arithmetic operation CODE. CODE
2150 is a tree code. The type of the result is taken from the operands.
2151 Both must be equivalent integer types, ala int_binop_types_match_p.
2152 If the operands are constant, so is the result. */
2155 size_binop_loc (location_t loc, enum tree_code code, tree arg0, tree arg1)
2157 tree type = TREE_TYPE (arg0);
2159 if (arg0 == error_mark_node || arg1 == error_mark_node)
2160 return error_mark_node;
2162 gcc_assert (int_binop_types_match_p (code, TREE_TYPE (arg0),
2165 /* Handle the special case of two integer constants faster. */
2166 if (TREE_CODE (arg0) == INTEGER_CST && TREE_CODE (arg1) == INTEGER_CST)
2168 /* And some specific cases even faster than that. */
2169 if (code == PLUS_EXPR)
2171 if (integer_zerop (arg0) && !TREE_OVERFLOW (arg0))
2173 if (integer_zerop (arg1) && !TREE_OVERFLOW (arg1))
2176 else if (code == MINUS_EXPR)
2178 if (integer_zerop (arg1) && !TREE_OVERFLOW (arg1))
2181 else if (code == MULT_EXPR)
2183 if (integer_onep (arg0) && !TREE_OVERFLOW (arg0))
2187 /* Handle general case of two integer constants. */
2188 return int_const_binop (code, arg0, arg1, 0);
2191 return fold_build2_loc (loc, code, type, arg0, arg1);
2194 /* Given two values, either both of sizetype or both of bitsizetype,
2195 compute the difference between the two values. Return the value
2196 in signed type corresponding to the type of the operands. */
2199 size_diffop_loc (location_t loc, tree arg0, tree arg1)
2201 tree type = TREE_TYPE (arg0);
2204 gcc_assert (int_binop_types_match_p (MINUS_EXPR, TREE_TYPE (arg0),
2207 /* If the type is already signed, just do the simple thing. */
2208 if (!TYPE_UNSIGNED (type))
2209 return size_binop_loc (loc, MINUS_EXPR, arg0, arg1);
2211 if (type == sizetype)
2213 else if (type == bitsizetype)
2214 ctype = sbitsizetype;
2216 ctype = signed_type_for (type);
2218 /* If either operand is not a constant, do the conversions to the signed
2219 type and subtract. The hardware will do the right thing with any
2220 overflow in the subtraction. */
2221 if (TREE_CODE (arg0) != INTEGER_CST || TREE_CODE (arg1) != INTEGER_CST)
2222 return size_binop_loc (loc, MINUS_EXPR,
2223 fold_convert_loc (loc, ctype, arg0),
2224 fold_convert_loc (loc, ctype, arg1));
2226 /* If ARG0 is larger than ARG1, subtract and return the result in CTYPE.
2227 Otherwise, subtract the other way, convert to CTYPE (we know that can't
2228 overflow) and negate (which can't either). Special-case a result
2229 of zero while we're here. */
2230 if (tree_int_cst_equal (arg0, arg1))
2231 return build_int_cst (ctype, 0);
2232 else if (tree_int_cst_lt (arg1, arg0))
2233 return fold_convert_loc (loc, ctype,
2234 size_binop_loc (loc, MINUS_EXPR, arg0, arg1));
2236 return size_binop_loc (loc, MINUS_EXPR, build_int_cst (ctype, 0),
2237 fold_convert_loc (loc, ctype,
2238 size_binop_loc (loc,
2243 /* A subroutine of fold_convert_const handling conversions of an
2244 INTEGER_CST to another integer type. */
2247 fold_convert_const_int_from_int (tree type, const_tree arg1)
2251 /* Given an integer constant, make new constant with new type,
2252 appropriately sign-extended or truncated. */
2253 t = force_fit_type_double (type, TREE_INT_CST_LOW (arg1),
2254 TREE_INT_CST_HIGH (arg1),
2255 /* Don't set the overflow when
2256 converting from a pointer, */
2257 !POINTER_TYPE_P (TREE_TYPE (arg1))
2258 /* or to a sizetype with same signedness
2259 and the precision is unchanged.
2260 ??? sizetype is always sign-extended,
2261 but its signedness depends on the
2262 frontend. Thus we see spurious overflows
2263 here if we do not check this. */
2264 && !((TYPE_PRECISION (TREE_TYPE (arg1))
2265 == TYPE_PRECISION (type))
2266 && (TYPE_UNSIGNED (TREE_TYPE (arg1))
2267 == TYPE_UNSIGNED (type))
2268 && ((TREE_CODE (TREE_TYPE (arg1)) == INTEGER_TYPE
2269 && TYPE_IS_SIZETYPE (TREE_TYPE (arg1)))
2270 || (TREE_CODE (type) == INTEGER_TYPE
2271 && TYPE_IS_SIZETYPE (type)))),
2272 (TREE_INT_CST_HIGH (arg1) < 0
2273 && (TYPE_UNSIGNED (type)
2274 < TYPE_UNSIGNED (TREE_TYPE (arg1))))
2275 | TREE_OVERFLOW (arg1));
2280 /* A subroutine of fold_convert_const handling conversions a REAL_CST
2281 to an integer type. */
2284 fold_convert_const_int_from_real (enum tree_code code, tree type, const_tree arg1)
2289 /* The following code implements the floating point to integer
2290 conversion rules required by the Java Language Specification,
2291 that IEEE NaNs are mapped to zero and values that overflow
2292 the target precision saturate, i.e. values greater than
2293 INT_MAX are mapped to INT_MAX, and values less than INT_MIN
2294 are mapped to INT_MIN. These semantics are allowed by the
2295 C and C++ standards that simply state that the behavior of
2296 FP-to-integer conversion is unspecified upon overflow. */
2298 HOST_WIDE_INT high, low;
2300 REAL_VALUE_TYPE x = TREE_REAL_CST (arg1);
2304 case FIX_TRUNC_EXPR:
2305 real_trunc (&r, VOIDmode, &x);
2312 /* If R is NaN, return zero and show we have an overflow. */
2313 if (REAL_VALUE_ISNAN (r))
2320 /* See if R is less than the lower bound or greater than the
2325 tree lt = TYPE_MIN_VALUE (type);
2326 REAL_VALUE_TYPE l = real_value_from_int_cst (NULL_TREE, lt);
2327 if (REAL_VALUES_LESS (r, l))
2330 high = TREE_INT_CST_HIGH (lt);
2331 low = TREE_INT_CST_LOW (lt);
2337 tree ut = TYPE_MAX_VALUE (type);
2340 REAL_VALUE_TYPE u = real_value_from_int_cst (NULL_TREE, ut);
2341 if (REAL_VALUES_LESS (u, r))
2344 high = TREE_INT_CST_HIGH (ut);
2345 low = TREE_INT_CST_LOW (ut);
2351 REAL_VALUE_TO_INT (&low, &high, r);
2353 t = force_fit_type_double (type, low, high, -1,
2354 overflow | TREE_OVERFLOW (arg1));
2358 /* A subroutine of fold_convert_const handling conversions of a
2359 FIXED_CST to an integer type. */
2362 fold_convert_const_int_from_fixed (tree type, const_tree arg1)
2365 double_int temp, temp_trunc;
2368 /* Right shift FIXED_CST to temp by fbit. */
2369 temp = TREE_FIXED_CST (arg1).data;
2370 mode = TREE_FIXED_CST (arg1).mode;
2371 if (GET_MODE_FBIT (mode) < 2 * HOST_BITS_PER_WIDE_INT)
2373 lshift_double (temp.low, temp.high,
2374 - GET_MODE_FBIT (mode), 2 * HOST_BITS_PER_WIDE_INT,
2375 &temp.low, &temp.high, SIGNED_FIXED_POINT_MODE_P (mode));
2377 /* Left shift temp to temp_trunc by fbit. */
2378 lshift_double (temp.low, temp.high,
2379 GET_MODE_FBIT (mode), 2 * HOST_BITS_PER_WIDE_INT,
2380 &temp_trunc.low, &temp_trunc.high,
2381 SIGNED_FIXED_POINT_MODE_P (mode));
2388 temp_trunc.high = 0;
2391 /* If FIXED_CST is negative, we need to round the value toward 0.
2392 By checking if the fractional bits are not zero to add 1 to temp. */
2393 if (SIGNED_FIXED_POINT_MODE_P (mode) && temp_trunc.high < 0
2394 && !double_int_equal_p (TREE_FIXED_CST (arg1).data, temp_trunc))
2399 temp = double_int_add (temp, one);
2402 /* Given a fixed-point constant, make new constant with new type,
2403 appropriately sign-extended or truncated. */
2404 t = force_fit_type_double (type, temp.low, temp.high, -1,
2406 && (TYPE_UNSIGNED (type)
2407 < TYPE_UNSIGNED (TREE_TYPE (arg1))))
2408 | TREE_OVERFLOW (arg1));
2413 /* A subroutine of fold_convert_const handling conversions a REAL_CST
2414 to another floating point type. */
2417 fold_convert_const_real_from_real (tree type, const_tree arg1)
2419 REAL_VALUE_TYPE value;
2422 real_convert (&value, TYPE_MODE (type), &TREE_REAL_CST (arg1));
2423 t = build_real (type, value);
2425 /* If converting an infinity or NAN to a representation that doesn't
2426 have one, set the overflow bit so that we can produce some kind of
2427 error message at the appropriate point if necessary. It's not the
2428 most user-friendly message, but it's better than nothing. */
2429 if (REAL_VALUE_ISINF (TREE_REAL_CST (arg1))
2430 && !MODE_HAS_INFINITIES (TYPE_MODE (type)))
2431 TREE_OVERFLOW (t) = 1;
2432 else if (REAL_VALUE_ISNAN (TREE_REAL_CST (arg1))
2433 && !MODE_HAS_NANS (TYPE_MODE (type)))
2434 TREE_OVERFLOW (t) = 1;
2435 /* Regular overflow, conversion produced an infinity in a mode that
2436 can't represent them. */
2437 else if (!MODE_HAS_INFINITIES (TYPE_MODE (type))
2438 && REAL_VALUE_ISINF (value)
2439 && !REAL_VALUE_ISINF (TREE_REAL_CST (arg1)))
2440 TREE_OVERFLOW (t) = 1;
2442 TREE_OVERFLOW (t) = TREE_OVERFLOW (arg1);
2446 /* A subroutine of fold_convert_const handling conversions a FIXED_CST
2447 to a floating point type. */
2450 fold_convert_const_real_from_fixed (tree type, const_tree arg1)
2452 REAL_VALUE_TYPE value;
2455 real_convert_from_fixed (&value, TYPE_MODE (type), &TREE_FIXED_CST (arg1));
2456 t = build_real (type, value);
2458 TREE_OVERFLOW (t) = TREE_OVERFLOW (arg1);
2462 /* A subroutine of fold_convert_const handling conversions a FIXED_CST
2463 to another fixed-point type. */
2466 fold_convert_const_fixed_from_fixed (tree type, const_tree arg1)
2468 FIXED_VALUE_TYPE value;
2472 overflow_p = fixed_convert (&value, TYPE_MODE (type), &TREE_FIXED_CST (arg1),
2473 TYPE_SATURATING (type));
2474 t = build_fixed (type, value);
2476 /* Propagate overflow flags. */
2477 if (overflow_p | TREE_OVERFLOW (arg1))
2478 TREE_OVERFLOW (t) = 1;
2482 /* A subroutine of fold_convert_const handling conversions an INTEGER_CST
2483 to a fixed-point type. */
2486 fold_convert_const_fixed_from_int (tree type, const_tree arg1)
2488 FIXED_VALUE_TYPE value;
2492 overflow_p = fixed_convert_from_int (&value, TYPE_MODE (type),
2493 TREE_INT_CST (arg1),
2494 TYPE_UNSIGNED (TREE_TYPE (arg1)),
2495 TYPE_SATURATING (type));
2496 t = build_fixed (type, value);
2498 /* Propagate overflow flags. */
2499 if (overflow_p | TREE_OVERFLOW (arg1))
2500 TREE_OVERFLOW (t) = 1;
2504 /* A subroutine of fold_convert_const handling conversions a REAL_CST
2505 to a fixed-point type. */
2508 fold_convert_const_fixed_from_real (tree type, const_tree arg1)
2510 FIXED_VALUE_TYPE value;
2514 overflow_p = fixed_convert_from_real (&value, TYPE_MODE (type),
2515 &TREE_REAL_CST (arg1),
2516 TYPE_SATURATING (type));
2517 t = build_fixed (type, value);
2519 /* Propagate overflow flags. */
2520 if (overflow_p | TREE_OVERFLOW (arg1))
2521 TREE_OVERFLOW (t) = 1;
2525 /* Attempt to fold type conversion operation CODE of expression ARG1 to
2526 type TYPE. If no simplification can be done return NULL_TREE. */
2529 fold_convert_const (enum tree_code code, tree type, tree arg1)
2531 if (TREE_TYPE (arg1) == type)
2534 if (POINTER_TYPE_P (type) || INTEGRAL_TYPE_P (type)
2535 || TREE_CODE (type) == OFFSET_TYPE)
2537 if (TREE_CODE (arg1) == INTEGER_CST)
2538 return fold_convert_const_int_from_int (type, arg1);
2539 else if (TREE_CODE (arg1) == REAL_CST)
2540 return fold_convert_const_int_from_real (code, type, arg1);
2541 else if (TREE_CODE (arg1) == FIXED_CST)
2542 return fold_convert_const_int_from_fixed (type, arg1);
2544 else if (TREE_CODE (type) == REAL_TYPE)
2546 if (TREE_CODE (arg1) == INTEGER_CST)
2547 return build_real_from_int_cst (type, arg1);
2548 else if (TREE_CODE (arg1) == REAL_CST)
2549 return fold_convert_const_real_from_real (type, arg1);
2550 else if (TREE_CODE (arg1) == FIXED_CST)
2551 return fold_convert_const_real_from_fixed (type, arg1);
2553 else if (TREE_CODE (type) == FIXED_POINT_TYPE)
2555 if (TREE_CODE (arg1) == FIXED_CST)
2556 return fold_convert_const_fixed_from_fixed (type, arg1);
2557 else if (TREE_CODE (arg1) == INTEGER_CST)
2558 return fold_convert_const_fixed_from_int (type, arg1);
2559 else if (TREE_CODE (arg1) == REAL_CST)
2560 return fold_convert_const_fixed_from_real (type, arg1);
2565 /* Construct a vector of zero elements of vector type TYPE. */
2568 build_zero_vector (tree type)
2573 elem = fold_convert_const (NOP_EXPR, TREE_TYPE (type), integer_zero_node);
2574 units = TYPE_VECTOR_SUBPARTS (type);
2577 for (i = 0; i < units; i++)
2578 list = tree_cons (NULL_TREE, elem, list);
2579 return build_vector (type, list);
2582 /* Returns true, if ARG is convertible to TYPE using a NOP_EXPR. */
2585 fold_convertible_p (const_tree type, const_tree arg)
2587 tree orig = TREE_TYPE (arg);
2592 if (TREE_CODE (arg) == ERROR_MARK
2593 || TREE_CODE (type) == ERROR_MARK
2594 || TREE_CODE (orig) == ERROR_MARK)
2597 if (TYPE_MAIN_VARIANT (type) == TYPE_MAIN_VARIANT (orig))
2600 switch (TREE_CODE (type))
2602 case INTEGER_TYPE: case ENUMERAL_TYPE: case BOOLEAN_TYPE:
2603 case POINTER_TYPE: case REFERENCE_TYPE:
2605 if (INTEGRAL_TYPE_P (orig) || POINTER_TYPE_P (orig)
2606 || TREE_CODE (orig) == OFFSET_TYPE)
2608 return (TREE_CODE (orig) == VECTOR_TYPE
2609 && tree_int_cst_equal (TYPE_SIZE (type), TYPE_SIZE (orig)));
2612 case FIXED_POINT_TYPE:
2616 return TREE_CODE (type) == TREE_CODE (orig);
2623 /* Convert expression ARG to type TYPE. Used by the middle-end for
2624 simple conversions in preference to calling the front-end's convert. */
2627 fold_convert_loc (location_t loc, tree type, tree arg)
2629 tree orig = TREE_TYPE (arg);
2635 if (TREE_CODE (arg) == ERROR_MARK
2636 || TREE_CODE (type) == ERROR_MARK
2637 || TREE_CODE (orig) == ERROR_MARK)
2638 return error_mark_node;
2640 if (TYPE_MAIN_VARIANT (type) == TYPE_MAIN_VARIANT (orig))
2641 return fold_build1_loc (loc, NOP_EXPR, type, arg);
2643 switch (TREE_CODE (type))
2646 case REFERENCE_TYPE:
2647 /* Handle conversions between pointers to different address spaces. */
2648 if (POINTER_TYPE_P (orig)
2649 && (TYPE_ADDR_SPACE (TREE_TYPE (type))
2650 != TYPE_ADDR_SPACE (TREE_TYPE (orig))))
2651 return fold_build1_loc (loc, ADDR_SPACE_CONVERT_EXPR, type, arg);
2654 case INTEGER_TYPE: case ENUMERAL_TYPE: case BOOLEAN_TYPE:
2656 if (TREE_CODE (arg) == INTEGER_CST)
2658 tem = fold_convert_const (NOP_EXPR, type, arg);
2659 if (tem != NULL_TREE)
2662 if (INTEGRAL_TYPE_P (orig) || POINTER_TYPE_P (orig)
2663 || TREE_CODE (orig) == OFFSET_TYPE)
2664 return fold_build1_loc (loc, NOP_EXPR, type, arg);
2665 if (TREE_CODE (orig) == COMPLEX_TYPE)
2666 return fold_convert_loc (loc, type,
2667 fold_build1_loc (loc, REALPART_EXPR,
2668 TREE_TYPE (orig), arg));
2669 gcc_assert (TREE_CODE (orig) == VECTOR_TYPE
2670 && tree_int_cst_equal (TYPE_SIZE (type), TYPE_SIZE (orig)));
2671 return fold_build1_loc (loc, NOP_EXPR, type, arg);
2674 if (TREE_CODE (arg) == INTEGER_CST)
2676 tem = fold_convert_const (FLOAT_EXPR, type, arg);
2677 if (tem != NULL_TREE)
2680 else if (TREE_CODE (arg) == REAL_CST)
2682 tem = fold_convert_const (NOP_EXPR, type, arg);
2683 if (tem != NULL_TREE)
2686 else if (TREE_CODE (arg) == FIXED_CST)
2688 tem = fold_convert_const (FIXED_CONVERT_EXPR, type, arg);
2689 if (tem != NULL_TREE)
2693 switch (TREE_CODE (orig))
2696 case BOOLEAN_TYPE: case ENUMERAL_TYPE:
2697 case POINTER_TYPE: case REFERENCE_TYPE:
2698 return fold_build1_loc (loc, FLOAT_EXPR, type, arg);
2701 return fold_build1_loc (loc, NOP_EXPR, type, arg);
2703 case FIXED_POINT_TYPE:
2704 return fold_build1_loc (loc, FIXED_CONVERT_EXPR, type, arg);
2707 tem = fold_build1_loc (loc, REALPART_EXPR, TREE_TYPE (orig), arg);
2708 return fold_convert_loc (loc, type, tem);
2714 case FIXED_POINT_TYPE:
2715 if (TREE_CODE (arg) == FIXED_CST || TREE_CODE (arg) == INTEGER_CST
2716 || TREE_CODE (arg) == REAL_CST)
2718 tem = fold_convert_const (FIXED_CONVERT_EXPR, type, arg);
2719 if (tem != NULL_TREE)
2720 goto fold_convert_exit;
2723 switch (TREE_CODE (orig))
2725 case FIXED_POINT_TYPE:
2730 return fold_build1_loc (loc, FIXED_CONVERT_EXPR, type, arg);
2733 tem = fold_build1_loc (loc, REALPART_EXPR, TREE_TYPE (orig), arg);
2734 return fold_convert_loc (loc, type, tem);
2741 switch (TREE_CODE (orig))
2744 case BOOLEAN_TYPE: case ENUMERAL_TYPE:
2745 case POINTER_TYPE: case REFERENCE_TYPE:
2747 case FIXED_POINT_TYPE:
2748 return fold_build2_loc (loc, COMPLEX_EXPR, type,
2749 fold_convert_loc (loc, TREE_TYPE (type), arg),
2750 fold_convert_loc (loc, TREE_TYPE (type),
2751 integer_zero_node));
2756 if (TREE_CODE (arg) == COMPLEX_EXPR)
2758 rpart = fold_convert_loc (loc, TREE_TYPE (type),
2759 TREE_OPERAND (arg, 0));
2760 ipart = fold_convert_loc (loc, TREE_TYPE (type),
2761 TREE_OPERAND (arg, 1));
2762 return fold_build2_loc (loc, COMPLEX_EXPR, type, rpart, ipart);
2765 arg = save_expr (arg);
2766 rpart = fold_build1_loc (loc, REALPART_EXPR, TREE_TYPE (orig), arg);
2767 ipart = fold_build1_loc (loc, IMAGPART_EXPR, TREE_TYPE (orig), arg);
2768 rpart = fold_convert_loc (loc, TREE_TYPE (type), rpart);
2769 ipart = fold_convert_loc (loc, TREE_TYPE (type), ipart);
2770 return fold_build2_loc (loc, COMPLEX_EXPR, type, rpart, ipart);
2778 if (integer_zerop (arg))
2779 return build_zero_vector (type);
2780 gcc_assert (tree_int_cst_equal (TYPE_SIZE (type), TYPE_SIZE (orig)));
2781 gcc_assert (INTEGRAL_TYPE_P (orig) || POINTER_TYPE_P (orig)
2782 || TREE_CODE (orig) == VECTOR_TYPE);
2783 return fold_build1_loc (loc, VIEW_CONVERT_EXPR, type, arg);
2786 tem = fold_ignored_result (arg);
2787 if (TREE_CODE (tem) == MODIFY_EXPR)
2788 goto fold_convert_exit;
2789 return fold_build1_loc (loc, NOP_EXPR, type, tem);
2795 protected_set_expr_location (tem, loc);
2799 /* Return false if expr can be assumed not to be an lvalue, true
2803 maybe_lvalue_p (const_tree x)
2805 /* We only need to wrap lvalue tree codes. */
2806 switch (TREE_CODE (x))
2817 case ALIGN_INDIRECT_REF:
2818 case MISALIGNED_INDIRECT_REF:
2820 case ARRAY_RANGE_REF:
2826 case PREINCREMENT_EXPR:
2827 case PREDECREMENT_EXPR:
2829 case TRY_CATCH_EXPR:
2830 case WITH_CLEANUP_EXPR:
2839 /* Assume the worst for front-end tree codes. */
2840 if ((int)TREE_CODE (x) >= NUM_TREE_CODES)
2848 /* Return an expr equal to X but certainly not valid as an lvalue. */
2851 non_lvalue_loc (location_t loc, tree x)
2853 /* While we are in GIMPLE, NON_LVALUE_EXPR doesn't mean anything to
2858 if (! maybe_lvalue_p (x))
2860 x = build1 (NON_LVALUE_EXPR, TREE_TYPE (x), x);
2861 SET_EXPR_LOCATION (x, loc);
2865 /* Nonzero means lvalues are limited to those valid in pedantic ANSI C.
2866 Zero means allow extended lvalues. */
2868 int pedantic_lvalues;
2870 /* When pedantic, return an expr equal to X but certainly not valid as a
2871 pedantic lvalue. Otherwise, return X. */
2874 pedantic_non_lvalue_loc (location_t loc, tree x)
2876 if (pedantic_lvalues)
2877 return non_lvalue_loc (loc, x);
2878 protected_set_expr_location (x, loc);
2882 /* Given a tree comparison code, return the code that is the logical inverse
2883 of the given code. It is not safe to do this for floating-point
2884 comparisons, except for NE_EXPR and EQ_EXPR, so we receive a machine mode
2885 as well: if reversing the comparison is unsafe, return ERROR_MARK. */
2888 invert_tree_comparison (enum tree_code code, bool honor_nans)
2890 if (honor_nans && flag_trapping_math)
2900 return honor_nans ? UNLE_EXPR : LE_EXPR;
2902 return honor_nans ? UNLT_EXPR : LT_EXPR;
2904 return honor_nans ? UNGE_EXPR : GE_EXPR;
2906 return honor_nans ? UNGT_EXPR : GT_EXPR;
2920 return UNORDERED_EXPR;
2921 case UNORDERED_EXPR:
2922 return ORDERED_EXPR;
2928 /* Similar, but return the comparison that results if the operands are
2929 swapped. This is safe for floating-point. */
2932 swap_tree_comparison (enum tree_code code)
2939 case UNORDERED_EXPR:
2965 /* Convert a comparison tree code from an enum tree_code representation
2966 into a compcode bit-based encoding. This function is the inverse of
2967 compcode_to_comparison. */
2969 static enum comparison_code
2970 comparison_to_compcode (enum tree_code code)
2987 return COMPCODE_ORD;
2988 case UNORDERED_EXPR:
2989 return COMPCODE_UNORD;
2991 return COMPCODE_UNLT;
2993 return COMPCODE_UNEQ;
2995 return COMPCODE_UNLE;
2997 return COMPCODE_UNGT;
2999 return COMPCODE_LTGT;
3001 return COMPCODE_UNGE;
3007 /* Convert a compcode bit-based encoding of a comparison operator back
3008 to GCC's enum tree_code representation. This function is the
3009 inverse of comparison_to_compcode. */
3011 static enum tree_code
3012 compcode_to_comparison (enum comparison_code code)
3029 return ORDERED_EXPR;
3030 case COMPCODE_UNORD:
3031 return UNORDERED_EXPR;
3049 /* Return a tree for the comparison which is the combination of
3050 doing the AND or OR (depending on CODE) of the two operations LCODE
3051 and RCODE on the identical operands LL_ARG and LR_ARG. Take into account
3052 the possibility of trapping if the mode has NaNs, and return NULL_TREE
3053 if this makes the transformation invalid. */
3056 combine_comparisons (location_t loc,
3057 enum tree_code code, enum tree_code lcode,
3058 enum tree_code rcode, tree truth_type,
3059 tree ll_arg, tree lr_arg)
3061 bool honor_nans = HONOR_NANS (TYPE_MODE (TREE_TYPE (ll_arg)));
3062 enum comparison_code lcompcode = comparison_to_compcode (lcode);
3063 enum comparison_code rcompcode = comparison_to_compcode (rcode);
3068 case TRUTH_AND_EXPR: case TRUTH_ANDIF_EXPR:
3069 compcode = lcompcode & rcompcode;
3072 case TRUTH_OR_EXPR: case TRUTH_ORIF_EXPR:
3073 compcode = lcompcode | rcompcode;
3082 /* Eliminate unordered comparisons, as well as LTGT and ORD
3083 which are not used unless the mode has NaNs. */
3084 compcode &= ~COMPCODE_UNORD;
3085 if (compcode == COMPCODE_LTGT)
3086 compcode = COMPCODE_NE;
3087 else if (compcode == COMPCODE_ORD)
3088 compcode = COMPCODE_TRUE;
3090 else if (flag_trapping_math)
3092 /* Check that the original operation and the optimized ones will trap
3093 under the same condition. */
3094 bool ltrap = (lcompcode & COMPCODE_UNORD) == 0
3095 && (lcompcode != COMPCODE_EQ)
3096 && (lcompcode != COMPCODE_ORD);
3097 bool rtrap = (rcompcode & COMPCODE_UNORD) == 0
3098 && (rcompcode != COMPCODE_EQ)
3099 && (rcompcode != COMPCODE_ORD);
3100 bool trap = (compcode & COMPCODE_UNORD) == 0
3101 && (compcode != COMPCODE_EQ)
3102 && (compcode != COMPCODE_ORD);
3104 /* In a short-circuited boolean expression the LHS might be
3105 such that the RHS, if evaluated, will never trap. For
3106 example, in ORD (x, y) && (x < y), we evaluate the RHS only
3107 if neither x nor y is NaN. (This is a mixed blessing: for
3108 example, the expression above will never trap, hence
3109 optimizing it to x < y would be invalid). */
3110 if ((code == TRUTH_ORIF_EXPR && (lcompcode & COMPCODE_UNORD))
3111 || (code == TRUTH_ANDIF_EXPR && !(lcompcode & COMPCODE_UNORD)))
3114 /* If the comparison was short-circuited, and only the RHS
3115 trapped, we may now generate a spurious trap. */
3117 && (code == TRUTH_ANDIF_EXPR || code == TRUTH_ORIF_EXPR))
3120 /* If we changed the conditions that cause a trap, we lose. */
3121 if ((ltrap || rtrap) != trap)
3125 if (compcode == COMPCODE_TRUE)
3126 return constant_boolean_node (true, truth_type);
3127 else if (compcode == COMPCODE_FALSE)
3128 return constant_boolean_node (false, truth_type);
3131 enum tree_code tcode;
3133 tcode = compcode_to_comparison ((enum comparison_code) compcode);
3134 return fold_build2_loc (loc, tcode, truth_type, ll_arg, lr_arg);
3138 /* Return nonzero if two operands (typically of the same tree node)
3139 are necessarily equal. If either argument has side-effects this
3140 function returns zero. FLAGS modifies behavior as follows:
3142 If OEP_ONLY_CONST is set, only return nonzero for constants.
3143 This function tests whether the operands are indistinguishable;
3144 it does not test whether they are equal using C's == operation.
3145 The distinction is important for IEEE floating point, because
3146 (1) -0.0 and 0.0 are distinguishable, but -0.0==0.0, and
3147 (2) two NaNs may be indistinguishable, but NaN!=NaN.
3149 If OEP_ONLY_CONST is unset, a VAR_DECL is considered equal to itself
3150 even though it may hold multiple values during a function.
3151 This is because a GCC tree node guarantees that nothing else is
3152 executed between the evaluation of its "operands" (which may often
3153 be evaluated in arbitrary order). Hence if the operands themselves
3154 don't side-effect, the VAR_DECLs, PARM_DECLs etc... must hold the
3155 same value in each operand/subexpression. Hence leaving OEP_ONLY_CONST
3156 unset means assuming isochronic (or instantaneous) tree equivalence.
3157 Unless comparing arbitrary expression trees, such as from different
3158 statements, this flag can usually be left unset.
3160 If OEP_PURE_SAME is set, then pure functions with identical arguments
3161 are considered the same. It is used when the caller has other ways
3162 to ensure that global memory is unchanged in between. */
3165 operand_equal_p (const_tree arg0, const_tree arg1, unsigned int flags)
3167 /* If either is ERROR_MARK, they aren't equal. */
3168 if (TREE_CODE (arg0) == ERROR_MARK || TREE_CODE (arg1) == ERROR_MARK
3169 || TREE_TYPE (arg0) == error_mark_node
3170 || TREE_TYPE (arg1) == error_mark_node)
3173 /* Similar, if either does not have a type (like a released SSA name),
3174 they aren't equal. */
3175 if (!TREE_TYPE (arg0) || !TREE_TYPE (arg1))
3178 /* Check equality of integer constants before bailing out due to
3179 precision differences. */
3180 if (TREE_CODE (arg0) == INTEGER_CST && TREE_CODE (arg1) == INTEGER_CST)
3181 return tree_int_cst_equal (arg0, arg1);
3183 /* If both types don't have the same signedness, then we can't consider
3184 them equal. We must check this before the STRIP_NOPS calls
3185 because they may change the signedness of the arguments. As pointers
3186 strictly don't have a signedness, require either two pointers or
3187 two non-pointers as well. */
3188 if (TYPE_UNSIGNED (TREE_TYPE (arg0)) != TYPE_UNSIGNED (TREE_TYPE (arg1))
3189 || POINTER_TYPE_P (TREE_TYPE (arg0)) != POINTER_TYPE_P (TREE_TYPE (arg1)))
3192 /* We cannot consider pointers to different address space equal. */
3193 if (POINTER_TYPE_P (TREE_TYPE (arg0)) && POINTER_TYPE_P (TREE_TYPE (arg1))
3194 && (TYPE_ADDR_SPACE (TREE_TYPE (TREE_TYPE (arg0)))
3195 != TYPE_ADDR_SPACE (TREE_TYPE (TREE_TYPE (arg1)))))
3198 /* If both types don't have the same precision, then it is not safe
3200 if (TYPE_PRECISION (TREE_TYPE (arg0)) != TYPE_PRECISION (TREE_TYPE (arg1)))
3206 /* In case both args are comparisons but with different comparison
3207 code, try to swap the comparison operands of one arg to produce
3208 a match and compare that variant. */
3209 if (TREE_CODE (arg0) != TREE_CODE (arg1)
3210 && COMPARISON_CLASS_P (arg0)
3211 && COMPARISON_CLASS_P (arg1))
3213 enum tree_code swap_code = swap_tree_comparison (TREE_CODE (arg1));
3215 if (TREE_CODE (arg0) == swap_code)
3216 return operand_equal_p (TREE_OPERAND (arg0, 0),
3217 TREE_OPERAND (arg1, 1), flags)
3218 && operand_equal_p (TREE_OPERAND (arg0, 1),
3219 TREE_OPERAND (arg1, 0), flags);
3222 if (TREE_CODE (arg0) != TREE_CODE (arg1)
3223 /* This is needed for conversions and for COMPONENT_REF.
3224 Might as well play it safe and always test this. */
3225 || TREE_CODE (TREE_TYPE (arg0)) == ERROR_MARK
3226 || TREE_CODE (TREE_TYPE (arg1)) == ERROR_MARK
3227 || TYPE_MODE (TREE_TYPE (arg0)) != TYPE_MODE (TREE_TYPE (arg1)))
3230 /* If ARG0 and ARG1 are the same SAVE_EXPR, they are necessarily equal.
3231 We don't care about side effects in that case because the SAVE_EXPR
3232 takes care of that for us. In all other cases, two expressions are
3233 equal if they have no side effects. If we have two identical
3234 expressions with side effects that should be treated the same due
3235 to the only side effects being identical SAVE_EXPR's, that will
3236 be detected in the recursive calls below. */
3237 if (arg0 == arg1 && ! (flags & OEP_ONLY_CONST)
3238 && (TREE_CODE (arg0) == SAVE_EXPR
3239 || (! TREE_SIDE_EFFECTS (arg0) && ! TREE_SIDE_EFFECTS (arg1))))
3242 /* Next handle constant cases, those for which we can return 1 even
3243 if ONLY_CONST is set. */
3244 if (TREE_CONSTANT (arg0) && TREE_CONSTANT (arg1))
3245 switch (TREE_CODE (arg0))
3248 return tree_int_cst_equal (arg0, arg1);
3251 return FIXED_VALUES_IDENTICAL (TREE_FIXED_CST (arg0),
3252 TREE_FIXED_CST (arg1));
3255 if (REAL_VALUES_IDENTICAL (TREE_REAL_CST (arg0),
3256 TREE_REAL_CST (arg1)))
3260 if (!HONOR_SIGNED_ZEROS (TYPE_MODE (TREE_TYPE (arg0))))
3262 /* If we do not distinguish between signed and unsigned zero,
3263 consider them equal. */
3264 if (real_zerop (arg0) && real_zerop (arg1))
3273 v1 = TREE_VECTOR_CST_ELTS (arg0);
3274 v2 = TREE_VECTOR_CST_ELTS (arg1);
3277 if (!operand_equal_p (TREE_VALUE (v1), TREE_VALUE (v2),
3280 v1 = TREE_CHAIN (v1);
3281 v2 = TREE_CHAIN (v2);
3288 return (operand_equal_p (TREE_REALPART (arg0), TREE_REALPART (arg1),
3290 && operand_equal_p (TREE_IMAGPART (arg0), TREE_IMAGPART (arg1),
3294 return (TREE_STRING_LENGTH (arg0) == TREE_STRING_LENGTH (arg1)
3295 && ! memcmp (TREE_STRING_POINTER (arg0),
3296 TREE_STRING_POINTER (arg1),
3297 TREE_STRING_LENGTH (arg0)));
3300 return operand_equal_p (TREE_OPERAND (arg0, 0), TREE_OPERAND (arg1, 0),
3306 if (flags & OEP_ONLY_CONST)
3309 /* Define macros to test an operand from arg0 and arg1 for equality and a
3310 variant that allows null and views null as being different from any
3311 non-null value. In the latter case, if either is null, the both
3312 must be; otherwise, do the normal comparison. */
3313 #define OP_SAME(N) operand_equal_p (TREE_OPERAND (arg0, N), \
3314 TREE_OPERAND (arg1, N), flags)
3316 #define OP_SAME_WITH_NULL(N) \
3317 ((!TREE_OPERAND (arg0, N) || !TREE_OPERAND (arg1, N)) \
3318 ? TREE_OPERAND (arg0, N) == TREE_OPERAND (arg1, N) : OP_SAME (N))
3320 switch (TREE_CODE_CLASS (TREE_CODE (arg0)))
3323 /* Two conversions are equal only if signedness and modes match. */
3324 switch (TREE_CODE (arg0))
3327 case FIX_TRUNC_EXPR:
3328 if (TYPE_UNSIGNED (TREE_TYPE (arg0))
3329 != TYPE_UNSIGNED (TREE_TYPE (arg1)))
3339 case tcc_comparison:
3341 if (OP_SAME (0) && OP_SAME (1))
3344 /* For commutative ops, allow the other order. */
3345 return (commutative_tree_code (TREE_CODE (arg0))
3346 && operand_equal_p (TREE_OPERAND (arg0, 0),
3347 TREE_OPERAND (arg1, 1), flags)
3348 && operand_equal_p (TREE_OPERAND (arg0, 1),
3349 TREE_OPERAND (arg1, 0), flags));
3352 /* If either of the pointer (or reference) expressions we are
3353 dereferencing contain a side effect, these cannot be equal. */
3354 if (TREE_SIDE_EFFECTS (arg0)
3355 || TREE_SIDE_EFFECTS (arg1))
3358 switch (TREE_CODE (arg0))
3361 case ALIGN_INDIRECT_REF:
3362 case MISALIGNED_INDIRECT_REF:
3368 case ARRAY_RANGE_REF:
3369 /* Operands 2 and 3 may be null.
3370 Compare the array index by value if it is constant first as we
3371 may have different types but same value here. */
3373 && (tree_int_cst_equal (TREE_OPERAND (arg0, 1),
3374 TREE_OPERAND (arg1, 1))
3376 && OP_SAME_WITH_NULL (2)
3377 && OP_SAME_WITH_NULL (3));
3380 /* Handle operand 2 the same as for ARRAY_REF. Operand 0
3381 may be NULL when we're called to compare MEM_EXPRs. */
3382 return OP_SAME_WITH_NULL (0)
3384 && OP_SAME_WITH_NULL (2);
3387 return OP_SAME (0) && OP_SAME (1) && OP_SAME (2);
3393 case tcc_expression:
3394 switch (TREE_CODE (arg0))
3397 case TRUTH_NOT_EXPR:
3400 case TRUTH_ANDIF_EXPR:
3401 case TRUTH_ORIF_EXPR:
3402 return OP_SAME (0) && OP_SAME (1);
3404 case TRUTH_AND_EXPR:
3406 case TRUTH_XOR_EXPR:
3407 if (OP_SAME (0) && OP_SAME (1))
3410 /* Otherwise take into account this is a commutative operation. */
3411 return (operand_equal_p (TREE_OPERAND (arg0, 0),
3412 TREE_OPERAND (arg1, 1), flags)
3413 && operand_equal_p (TREE_OPERAND (arg0, 1),
3414 TREE_OPERAND (arg1, 0), flags));
3417 return OP_SAME (0) && OP_SAME (1) && OP_SAME (2);
3424 switch (TREE_CODE (arg0))
3427 /* If the CALL_EXPRs call different functions, then they
3428 clearly can not be equal. */
3429 if (! operand_equal_p (CALL_EXPR_FN (arg0), CALL_EXPR_FN (arg1),
3434 unsigned int cef = call_expr_flags (arg0);
3435 if (flags & OEP_PURE_SAME)
3436 cef &= ECF_CONST | ECF_PURE;
3443 /* Now see if all the arguments are the same. */
3445 const_call_expr_arg_iterator iter0, iter1;
3447 for (a0 = first_const_call_expr_arg (arg0, &iter0),
3448 a1 = first_const_call_expr_arg (arg1, &iter1);
3450 a0 = next_const_call_expr_arg (&iter0),
3451 a1 = next_const_call_expr_arg (&iter1))
3452 if (! operand_equal_p (a0, a1, flags))
3455 /* If we get here and both argument lists are exhausted
3456 then the CALL_EXPRs are equal. */
3457 return ! (a0 || a1);
3463 case tcc_declaration:
3464 /* Consider __builtin_sqrt equal to sqrt. */
3465 return (TREE_CODE (arg0) == FUNCTION_DECL
3466 && DECL_BUILT_IN (arg0) && DECL_BUILT_IN (arg1)
3467 && DECL_BUILT_IN_CLASS (arg0) == DECL_BUILT_IN_CLASS (arg1)
3468 && DECL_FUNCTION_CODE (arg0) == DECL_FUNCTION_CODE (arg1));
3475 #undef OP_SAME_WITH_NULL
3478 /* Similar to operand_equal_p, but see if ARG0 might have been made by
3479 shorten_compare from ARG1 when ARG1 was being compared with OTHER.
3481 When in doubt, return 0. */
3484 operand_equal_for_comparison_p (tree arg0, tree arg1, tree other)
3486 int unsignedp1, unsignedpo;
3487 tree primarg0, primarg1, primother;
3488 unsigned int correct_width;
3490 if (operand_equal_p (arg0, arg1, 0))
3493 if (! INTEGRAL_TYPE_P (TREE_TYPE (arg0))
3494 || ! INTEGRAL_TYPE_P (TREE_TYPE (arg1)))
3497 /* Discard any conversions that don't change the modes of ARG0 and ARG1
3498 and see if the inner values are the same. This removes any
3499 signedness comparison, which doesn't matter here. */
3500 primarg0 = arg0, primarg1 = arg1;
3501 STRIP_NOPS (primarg0);
3502 STRIP_NOPS (primarg1);
3503 if (operand_equal_p (primarg0, primarg1, 0))
3506 /* Duplicate what shorten_compare does to ARG1 and see if that gives the
3507 actual comparison operand, ARG0.
3509 First throw away any conversions to wider types
3510 already present in the operands. */
3512 primarg1 = get_narrower (arg1, &unsignedp1);
3513 primother = get_narrower (other, &unsignedpo);
3515 correct_width = TYPE_PRECISION (TREE_TYPE (arg1));
3516 if (unsignedp1 == unsignedpo
3517 && TYPE_PRECISION (TREE_TYPE (primarg1)) < correct_width
3518 && TYPE_PRECISION (TREE_TYPE (primother)) < correct_width)
3520 tree type = TREE_TYPE (arg0);
3522 /* Make sure shorter operand is extended the right way
3523 to match the longer operand. */
3524 primarg1 = fold_convert (signed_or_unsigned_type_for
3525 (unsignedp1, TREE_TYPE (primarg1)), primarg1);
3527 if (operand_equal_p (arg0, fold_convert (type, primarg1), 0))
3534 /* See if ARG is an expression that is either a comparison or is performing
3535 arithmetic on comparisons. The comparisons must only be comparing
3536 two different values, which will be stored in *CVAL1 and *CVAL2; if
3537 they are nonzero it means that some operands have already been found.
3538 No variables may be used anywhere else in the expression except in the
3539 comparisons. If SAVE_P is true it means we removed a SAVE_EXPR around
3540 the expression and save_expr needs to be called with CVAL1 and CVAL2.
3542 If this is true, return 1. Otherwise, return zero. */
3545 twoval_comparison_p (tree arg, tree *cval1, tree *cval2, int *save_p)
3547 enum tree_code code = TREE_CODE (arg);
3548 enum tree_code_class tclass = TREE_CODE_CLASS (code);
3550 /* We can handle some of the tcc_expression cases here. */
3551 if (tclass == tcc_expression && code == TRUTH_NOT_EXPR)
3553 else if (tclass == tcc_expression
3554 && (code == TRUTH_ANDIF_EXPR || code == TRUTH_ORIF_EXPR
3555 || code == COMPOUND_EXPR))
3556 tclass = tcc_binary;
3558 else if (tclass == tcc_expression && code == SAVE_EXPR
3559 && ! TREE_SIDE_EFFECTS (TREE_OPERAND (arg, 0)))
3561 /* If we've already found a CVAL1 or CVAL2, this expression is
3562 two complex to handle. */
3563 if (*cval1 || *cval2)
3573 return twoval_comparison_p (TREE_OPERAND (arg, 0), cval1, cval2, save_p);
3576 return (twoval_comparison_p (TREE_OPERAND (arg, 0), cval1, cval2, save_p)
3577 && twoval_comparison_p (TREE_OPERAND (arg, 1),
3578 cval1, cval2, save_p));
3583 case tcc_expression:
3584 if (code == COND_EXPR)
3585 return (twoval_comparison_p (TREE_OPERAND (arg, 0),
3586 cval1, cval2, save_p)
3587 && twoval_comparison_p (TREE_OPERAND (arg, 1),
3588 cval1, cval2, save_p)
3589 && twoval_comparison_p (TREE_OPERAND (arg, 2),
3590 cval1, cval2, save_p));
3593 case tcc_comparison:
3594 /* First see if we can handle the first operand, then the second. For
3595 the second operand, we know *CVAL1 can't be zero. It must be that
3596 one side of the comparison is each of the values; test for the
3597 case where this isn't true by failing if the two operands
3600 if (operand_equal_p (TREE_OPERAND (arg, 0),
3601 TREE_OPERAND (arg, 1), 0))
3605 *cval1 = TREE_OPERAND (arg, 0);
3606 else if (operand_equal_p (*cval1, TREE_OPERAND (arg, 0), 0))
3608 else if (*cval2 == 0)
3609 *cval2 = TREE_OPERAND (arg, 0);
3610 else if (operand_equal_p (*cval2, TREE_OPERAND (arg, 0), 0))
3615 if (operand_equal_p (*cval1, TREE_OPERAND (arg, 1), 0))
3617 else if (*cval2 == 0)
3618 *cval2 = TREE_OPERAND (arg, 1);
3619 else if (operand_equal_p (*cval2, TREE_OPERAND (arg, 1), 0))
3631 /* ARG is a tree that is known to contain just arithmetic operations and
3632 comparisons. Evaluate the operations in the tree substituting NEW0 for
3633 any occurrence of OLD0 as an operand of a comparison and likewise for
3637 eval_subst (location_t loc, tree arg, tree old0, tree new0,
3638 tree old1, tree new1)
3640 tree type = TREE_TYPE (arg);
3641 enum tree_code code = TREE_CODE (arg);
3642 enum tree_code_class tclass = TREE_CODE_CLASS (code);
3644 /* We can handle some of the tcc_expression cases here. */
3645 if (tclass == tcc_expression && code == TRUTH_NOT_EXPR)
3647 else if (tclass == tcc_expression
3648 && (code == TRUTH_ANDIF_EXPR || code == TRUTH_ORIF_EXPR))
3649 tclass = tcc_binary;
3654 return fold_build1_loc (loc, code, type,
3655 eval_subst (loc, TREE_OPERAND (arg, 0),
3656 old0, new0, old1, new1));
3659 return fold_build2_loc (loc, code, type,
3660 eval_subst (loc, TREE_OPERAND (arg, 0),
3661 old0, new0, old1, new1),
3662 eval_subst (loc, TREE_OPERAND (arg, 1),
3663 old0, new0, old1, new1));
3665 case tcc_expression:
3669 return eval_subst (loc, TREE_OPERAND (arg, 0), old0, new0,
3673 return eval_subst (loc, TREE_OPERAND (arg, 1), old0, new0,
3677 return fold_build3_loc (loc, code, type,
3678 eval_subst (loc, TREE_OPERAND (arg, 0),
3679 old0, new0, old1, new1),
3680 eval_subst (loc, TREE_OPERAND (arg, 1),
3681 old0, new0, old1, new1),
3682 eval_subst (loc, TREE_OPERAND (arg, 2),
3683 old0, new0, old1, new1));
3687 /* Fall through - ??? */
3689 case tcc_comparison:
3691 tree arg0 = TREE_OPERAND (arg, 0);
3692 tree arg1 = TREE_OPERAND (arg, 1);
3694 /* We need to check both for exact equality and tree equality. The
3695 former will be true if the operand has a side-effect. In that
3696 case, we know the operand occurred exactly once. */
3698 if (arg0 == old0 || operand_equal_p (arg0, old0, 0))
3700 else if (arg0 == old1 || operand_equal_p (arg0, old1, 0))
3703 if (arg1 == old0 || operand_equal_p (arg1, old0, 0))
3705 else if (arg1 == old1 || operand_equal_p (arg1, old1, 0))
3708 return fold_build2_loc (loc, code, type, arg0, arg1);
3716 /* Return a tree for the case when the result of an expression is RESULT
3717 converted to TYPE and OMITTED was previously an operand of the expression
3718 but is now not needed (e.g., we folded OMITTED * 0).
3720 If OMITTED has side effects, we must evaluate it. Otherwise, just do
3721 the conversion of RESULT to TYPE. */
3724 omit_one_operand_loc (location_t loc, tree type, tree result, tree omitted)
3726 tree t = fold_convert_loc (loc, type, result);
3728 /* If the resulting operand is an empty statement, just return the omitted
3729 statement casted to void. */
3730 if (IS_EMPTY_STMT (t) && TREE_SIDE_EFFECTS (omitted))
3732 t = build1 (NOP_EXPR, void_type_node, fold_ignored_result (omitted));
3733 goto omit_one_operand_exit;
3736 if (TREE_SIDE_EFFECTS (omitted))
3738 t = build2 (COMPOUND_EXPR, type, fold_ignored_result (omitted), t);
3739 goto omit_one_operand_exit;
3742 return non_lvalue_loc (loc, t);
3744 omit_one_operand_exit:
3745 protected_set_expr_location (t, loc);
3749 /* Similar, but call pedantic_non_lvalue instead of non_lvalue. */
3752 pedantic_omit_one_operand_loc (location_t loc, tree type, tree result,
3755 tree t = fold_convert_loc (loc, type, result);
3757 /* If the resulting operand is an empty statement, just return the omitted
3758 statement casted to void. */
3759 if (IS_EMPTY_STMT (t) && TREE_SIDE_EFFECTS (omitted))
3761 t = build1 (NOP_EXPR, void_type_node, fold_ignored_result (omitted));
3762 goto pedantic_omit_one_operand_exit;
3765 if (TREE_SIDE_EFFECTS (omitted))
3767 t = build2 (COMPOUND_EXPR, type, fold_ignored_result (omitted), t);
3768 goto pedantic_omit_one_operand_exit;
3771 return pedantic_non_lvalue_loc (loc, t);
3773 pedantic_omit_one_operand_exit:
3774 protected_set_expr_location (t, loc);
3778 /* Return a tree for the case when the result of an expression is RESULT
3779 converted to TYPE and OMITTED1 and OMITTED2 were previously operands
3780 of the expression but are now not needed.
3782 If OMITTED1 or OMITTED2 has side effects, they must be evaluated.
3783 If both OMITTED1 and OMITTED2 have side effects, OMITTED1 is
3784 evaluated before OMITTED2. Otherwise, if neither has side effects,
3785 just do the conversion of RESULT to TYPE. */
3788 omit_two_operands_loc (location_t loc, tree type, tree result,
3789 tree omitted1, tree omitted2)
3791 tree t = fold_convert_loc (loc, type, result);
3793 if (TREE_SIDE_EFFECTS (omitted2))
3795 t = build2 (COMPOUND_EXPR, type, omitted2, t);
3796 SET_EXPR_LOCATION (t, loc);
3798 if (TREE_SIDE_EFFECTS (omitted1))
3800 t = build2 (COMPOUND_EXPR, type, omitted1, t);
3801 SET_EXPR_LOCATION (t, loc);
3804 return TREE_CODE (t) != COMPOUND_EXPR ? non_lvalue_loc (loc, t) : t;
3808 /* Return a simplified tree node for the truth-negation of ARG. This
3809 never alters ARG itself. We assume that ARG is an operation that
3810 returns a truth value (0 or 1).
3812 FIXME: one would think we would fold the result, but it causes
3813 problems with the dominator optimizer. */
3816 fold_truth_not_expr (location_t loc, tree arg)
3818 tree t, type = TREE_TYPE (arg);
3819 enum tree_code code = TREE_CODE (arg);
3820 location_t loc1, loc2;
3822 /* If this is a comparison, we can simply invert it, except for
3823 floating-point non-equality comparisons, in which case we just
3824 enclose a TRUTH_NOT_EXPR around what we have. */
3826 if (TREE_CODE_CLASS (code) == tcc_comparison)
3828 tree op_type = TREE_TYPE (TREE_OPERAND (arg, 0));
3829 if (FLOAT_TYPE_P (op_type)
3830 && flag_trapping_math
3831 && code != ORDERED_EXPR && code != UNORDERED_EXPR
3832 && code != NE_EXPR && code != EQ_EXPR)
3835 code = invert_tree_comparison (code, HONOR_NANS (TYPE_MODE (op_type)));
3836 if (code == ERROR_MARK)
3839 t = build2 (code, type, TREE_OPERAND (arg, 0), TREE_OPERAND (arg, 1));
3840 SET_EXPR_LOCATION (t, loc);
3847 return constant_boolean_node (integer_zerop (arg), type);
3849 case TRUTH_AND_EXPR:
3850 loc1 = EXPR_LOCATION (TREE_OPERAND (arg, 0));
3851 loc2 = EXPR_LOCATION (TREE_OPERAND (arg, 1));
3852 if (loc1 == UNKNOWN_LOCATION)
3854 if (loc2 == UNKNOWN_LOCATION)
3856 t = build2 (TRUTH_OR_EXPR, type,
3857 invert_truthvalue_loc (loc1, TREE_OPERAND (arg, 0)),
3858 invert_truthvalue_loc (loc2, TREE_OPERAND (arg, 1)));
3862 loc1 = EXPR_LOCATION (TREE_OPERAND (arg, 0));
3863 loc2 = EXPR_LOCATION (TREE_OPERAND (arg, 1));
3864 if (loc1 == UNKNOWN_LOCATION)
3866 if (loc2 == UNKNOWN_LOCATION)
3868 t = build2 (TRUTH_AND_EXPR, type,
3869 invert_truthvalue_loc (loc1, TREE_OPERAND (arg, 0)),
3870 invert_truthvalue_loc (loc2, TREE_OPERAND (arg, 1)));
3873 case TRUTH_XOR_EXPR:
3874 /* Here we can invert either operand. We invert the first operand
3875 unless the second operand is a TRUTH_NOT_EXPR in which case our
3876 result is the XOR of the first operand with the inside of the
3877 negation of the second operand. */
3879 if (TREE_CODE (TREE_OPERAND (arg, 1)) == TRUTH_NOT_EXPR)
3880 t = build2 (TRUTH_XOR_EXPR, type, TREE_OPERAND (arg, 0),
3881 TREE_OPERAND (TREE_OPERAND (arg, 1), 0));
3883 t = build2 (TRUTH_XOR_EXPR, type,
3884 invert_truthvalue_loc (loc, TREE_OPERAND (arg, 0)),
3885 TREE_OPERAND (arg, 1));
3888 case TRUTH_ANDIF_EXPR:
3889 loc1 = EXPR_LOCATION (TREE_OPERAND (arg, 0));
3890 loc2 = EXPR_LOCATION (TREE_OPERAND (arg, 1));
3891 if (loc1 == UNKNOWN_LOCATION)
3893 if (loc2 == UNKNOWN_LOCATION)
3895 t = build2 (TRUTH_ORIF_EXPR, type,
3896 invert_truthvalue_loc (loc1, TREE_OPERAND (arg, 0)),
3897 invert_truthvalue_loc (loc2, TREE_OPERAND (arg, 1)));
3900 case TRUTH_ORIF_EXPR:
3901 loc1 = EXPR_LOCATION (TREE_OPERAND (arg, 0));
3902 loc2 = EXPR_LOCATION (TREE_OPERAND (arg, 1));
3903 if (loc1 == UNKNOWN_LOCATION)
3905 if (loc2 == UNKNOWN_LOCATION)
3907 t = build2 (TRUTH_ANDIF_EXPR, type,
3908 invert_truthvalue_loc (loc1, TREE_OPERAND (arg, 0)),
3909 invert_truthvalue_loc (loc2, TREE_OPERAND (arg, 1)));
3912 case TRUTH_NOT_EXPR:
3913 return TREE_OPERAND (arg, 0);
3917 tree arg1 = TREE_OPERAND (arg, 1);
3918 tree arg2 = TREE_OPERAND (arg, 2);
3920 loc1 = EXPR_LOCATION (TREE_OPERAND (arg, 1));
3921 loc2 = EXPR_LOCATION (TREE_OPERAND (arg, 2));
3922 if (loc1 == UNKNOWN_LOCATION)
3924 if (loc2 == UNKNOWN_LOCATION)
3927 /* A COND_EXPR may have a throw as one operand, which
3928 then has void type. Just leave void operands
3930 t = build3 (COND_EXPR, type, TREE_OPERAND (arg, 0),
3931 VOID_TYPE_P (TREE_TYPE (arg1))
3932 ? arg1 : invert_truthvalue_loc (loc1, arg1),
3933 VOID_TYPE_P (TREE_TYPE (arg2))
3934 ? arg2 : invert_truthvalue_loc (loc2, arg2));
3939 loc1 = EXPR_LOCATION (TREE_OPERAND (arg, 1));
3940 if (loc1 == UNKNOWN_LOCATION)
3942 t = build2 (COMPOUND_EXPR, type,
3943 TREE_OPERAND (arg, 0),
3944 invert_truthvalue_loc (loc1, TREE_OPERAND (arg, 1)));
3947 case NON_LVALUE_EXPR:
3948 loc1 = EXPR_LOCATION (TREE_OPERAND (arg, 0));
3949 if (loc1 == UNKNOWN_LOCATION)
3951 return invert_truthvalue_loc (loc1, TREE_OPERAND (arg, 0));
3954 if (TREE_CODE (TREE_TYPE (arg)) == BOOLEAN_TYPE)
3956 t = build1 (TRUTH_NOT_EXPR, type, arg);
3960 /* ... fall through ... */
3963 loc1 = EXPR_LOCATION (TREE_OPERAND (arg, 0));
3964 if (loc1 == UNKNOWN_LOCATION)
3966 t = build1 (TREE_CODE (arg), type,
3967 invert_truthvalue_loc (loc1, TREE_OPERAND (arg, 0)));
3971 if (!integer_onep (TREE_OPERAND (arg, 1)))
3973 t = build2 (EQ_EXPR, type, arg, build_int_cst (type, 0));
3977 t = build1 (TRUTH_NOT_EXPR, type, arg);
3980 case CLEANUP_POINT_EXPR:
3981 loc1 = EXPR_LOCATION (TREE_OPERAND (arg, 0));
3982 if (loc1 == UNKNOWN_LOCATION)
3984 t = build1 (CLEANUP_POINT_EXPR, type,
3985 invert_truthvalue_loc (loc1, TREE_OPERAND (arg, 0)));
3994 SET_EXPR_LOCATION (t, loc);
3999 /* Return a simplified tree node for the truth-negation of ARG. This
4000 never alters ARG itself. We assume that ARG is an operation that
4001 returns a truth value (0 or 1).
4003 FIXME: one would think we would fold the result, but it causes
4004 problems with the dominator optimizer. */
4007 invert_truthvalue_loc (location_t loc, tree arg)
4011 if (TREE_CODE (arg) == ERROR_MARK)
4014 tem = fold_truth_not_expr (loc, arg);
4017 tem = build1 (TRUTH_NOT_EXPR, TREE_TYPE (arg), arg);
4018 SET_EXPR_LOCATION (tem, loc);
4024 /* Given a bit-wise operation CODE applied to ARG0 and ARG1, see if both
4025 operands are another bit-wise operation with a common input. If so,
4026 distribute the bit operations to save an operation and possibly two if
4027 constants are involved. For example, convert
4028 (A | B) & (A | C) into A | (B & C)
4029 Further simplification will occur if B and C are constants.
4031 If this optimization cannot be done, 0 will be returned. */
4034 distribute_bit_expr (location_t loc, enum tree_code code, tree type,
4035 tree arg0, tree arg1)
4040 if (TREE_CODE (arg0) != TREE_CODE (arg1)
4041 || TREE_CODE (arg0) == code
4042 || (TREE_CODE (arg0) != BIT_AND_EXPR
4043 && TREE_CODE (arg0) != BIT_IOR_EXPR))
4046 if (operand_equal_p (TREE_OPERAND (arg0, 0), TREE_OPERAND (arg1, 0), 0))
4048 common = TREE_OPERAND (arg0, 0);
4049 left = TREE_OPERAND (arg0, 1);
4050 right = TREE_OPERAND (arg1, 1);
4052 else if (operand_equal_p (TREE_OPERAND (arg0, 0), TREE_OPERAND (arg1, 1), 0))
4054 common = TREE_OPERAND (arg0, 0);
4055 left = TREE_OPERAND (arg0, 1);
4056 right = TREE_OPERAND (arg1, 0);
4058 else if (operand_equal_p (TREE_OPERAND (arg0, 1), TREE_OPERAND (arg1, 0), 0))
4060 common = TREE_OPERAND (arg0, 1);
4061 left = TREE_OPERAND (arg0, 0);
4062 right = TREE_OPERAND (arg1, 1);
4064 else if (operand_equal_p (TREE_OPERAND (arg0, 1), TREE_OPERAND (arg1, 1), 0))
4066 common = TREE_OPERAND (arg0, 1);
4067 left = TREE_OPERAND (arg0, 0);
4068 right = TREE_OPERAND (arg1, 0);
4073 common = fold_convert_loc (loc, type, common);
4074 left = fold_convert_loc (loc, type, left);
4075 right = fold_convert_loc (loc, type, right);
4076 return fold_build2_loc (loc, TREE_CODE (arg0), type, common,
4077 fold_build2_loc (loc, code, type, left, right));
4080 /* Knowing that ARG0 and ARG1 are both RDIV_EXPRs, simplify a binary operation
4081 with code CODE. This optimization is unsafe. */
4083 distribute_real_division (location_t loc, enum tree_code code, tree type,
4084 tree arg0, tree arg1)
4086 bool mul0 = TREE_CODE (arg0) == MULT_EXPR;
4087 bool mul1 = TREE_CODE (arg1) == MULT_EXPR;
4089 /* (A / C) +- (B / C) -> (A +- B) / C. */
4091 && operand_equal_p (TREE_OPERAND (arg0, 1),
4092 TREE_OPERAND (arg1, 1), 0))
4093 return fold_build2_loc (loc, mul0 ? MULT_EXPR : RDIV_EXPR, type,
4094 fold_build2_loc (loc, code, type,
4095 TREE_OPERAND (arg0, 0),
4096 TREE_OPERAND (arg1, 0)),
4097 TREE_OPERAND (arg0, 1));
4099 /* (A / C1) +- (A / C2) -> A * (1 / C1 +- 1 / C2). */
4100 if (operand_equal_p (TREE_OPERAND (arg0, 0),
4101 TREE_OPERAND (arg1, 0), 0)
4102 && TREE_CODE (TREE_OPERAND (arg0, 1)) == REAL_CST
4103 && TREE_CODE (TREE_OPERAND (arg1, 1)) == REAL_CST)
4105 REAL_VALUE_TYPE r0, r1;
4106 r0 = TREE_REAL_CST (TREE_OPERAND (arg0, 1));
4107 r1 = TREE_REAL_CST (TREE_OPERAND (arg1, 1));
4109 real_arithmetic (&r0, RDIV_EXPR, &dconst1, &r0);
4111 real_arithmetic (&r1, RDIV_EXPR, &dconst1, &r1);
4112 real_arithmetic (&r0, code, &r0, &r1);
4113 return fold_build2_loc (loc, MULT_EXPR, type,
4114 TREE_OPERAND (arg0, 0),
4115 build_real (type, r0));
4121 /* Return a BIT_FIELD_REF of type TYPE to refer to BITSIZE bits of INNER
4122 starting at BITPOS. The field is unsigned if UNSIGNEDP is nonzero. */
4125 make_bit_field_ref (location_t loc, tree inner, tree type,
4126 HOST_WIDE_INT bitsize, HOST_WIDE_INT bitpos, int unsignedp)
4128 tree result, bftype;
4132 tree size = TYPE_SIZE (TREE_TYPE (inner));
4133 if ((INTEGRAL_TYPE_P (TREE_TYPE (inner))
4134 || POINTER_TYPE_P (TREE_TYPE (inner)))
4135 && host_integerp (size, 0)
4136 && tree_low_cst (size, 0) == bitsize)
4137 return fold_convert_loc (loc, type, inner);
4141 if (TYPE_PRECISION (bftype) != bitsize
4142 || TYPE_UNSIGNED (bftype) == !unsignedp)
4143 bftype = build_nonstandard_integer_type (bitsize, 0);
4145 result = build3 (BIT_FIELD_REF, bftype, inner,
4146 size_int (bitsize), bitsize_int (bitpos));
4147 SET_EXPR_LOCATION (result, loc);
4150 result = fold_convert_loc (loc, type, result);
4155 /* Optimize a bit-field compare.
4157 There are two cases: First is a compare against a constant and the
4158 second is a comparison of two items where the fields are at the same
4159 bit position relative to the start of a chunk (byte, halfword, word)
4160 large enough to contain it. In these cases we can avoid the shift
4161 implicit in bitfield extractions.
4163 For constants, we emit a compare of the shifted constant with the
4164 BIT_AND_EXPR of a mask and a byte, halfword, or word of the operand being
4165 compared. For two fields at the same position, we do the ANDs with the
4166 similar mask and compare the result of the ANDs.
4168 CODE is the comparison code, known to be either NE_EXPR or EQ_EXPR.
4169 COMPARE_TYPE is the type of the comparison, and LHS and RHS
4170 are the left and right operands of the comparison, respectively.
4172 If the optimization described above can be done, we return the resulting
4173 tree. Otherwise we return zero. */
4176 optimize_bit_field_compare (location_t loc, enum tree_code code,
4177 tree compare_type, tree lhs, tree rhs)
4179 HOST_WIDE_INT lbitpos, lbitsize, rbitpos, rbitsize, nbitpos, nbitsize;
4180 tree type = TREE_TYPE (lhs);
4181 tree signed_type, unsigned_type;
4182 int const_p = TREE_CODE (rhs) == INTEGER_CST;
4183 enum machine_mode lmode, rmode, nmode;
4184 int lunsignedp, runsignedp;
4185 int lvolatilep = 0, rvolatilep = 0;
4186 tree linner, rinner = NULL_TREE;
4190 /* Get all the information about the extractions being done. If the bit size
4191 if the same as the size of the underlying object, we aren't doing an
4192 extraction at all and so can do nothing. We also don't want to
4193 do anything if the inner expression is a PLACEHOLDER_EXPR since we
4194 then will no longer be able to replace it. */
4195 linner = get_inner_reference (lhs, &lbitsize, &lbitpos, &offset, &lmode,
4196 &lunsignedp, &lvolatilep, false);
4197 if (linner == lhs || lbitsize == GET_MODE_BITSIZE (lmode) || lbitsize < 0
4198 || offset != 0 || TREE_CODE (linner) == PLACEHOLDER_EXPR)
4203 /* If this is not a constant, we can only do something if bit positions,
4204 sizes, and signedness are the same. */
4205 rinner = get_inner_reference (rhs, &rbitsize, &rbitpos, &offset, &rmode,
4206 &runsignedp, &rvolatilep, false);
4208 if (rinner == rhs || lbitpos != rbitpos || lbitsize != rbitsize
4209 || lunsignedp != runsignedp || offset != 0
4210 || TREE_CODE (rinner) == PLACEHOLDER_EXPR)
4214 /* See if we can find a mode to refer to this field. We should be able to,
4215 but fail if we can't. */
4216 nmode = get_best_mode (lbitsize, lbitpos,
4217 const_p ? TYPE_ALIGN (TREE_TYPE (linner))
4218 : MIN (TYPE_ALIGN (TREE_TYPE (linner)),
4219 TYPE_ALIGN (TREE_TYPE (rinner))),
4220 word_mode, lvolatilep || rvolatilep);
4221 if (nmode == VOIDmode)
4224 /* Set signed and unsigned types of the precision of this mode for the
4226 signed_type = lang_hooks.types.type_for_mode (nmode, 0);
4227 unsigned_type = lang_hooks.types.type_for_mode (nmode, 1);
4229 /* Compute the bit position and size for the new reference and our offset
4230 within it. If the new reference is the same size as the original, we
4231 won't optimize anything, so return zero. */
4232 nbitsize = GET_MODE_BITSIZE (nmode);
4233 nbitpos = lbitpos & ~ (nbitsize - 1);
4235 if (nbitsize == lbitsize)
4238 if (BYTES_BIG_ENDIAN)
4239 lbitpos = nbitsize - lbitsize - lbitpos;
4241 /* Make the mask to be used against the extracted field. */
4242 mask = build_int_cst_type (unsigned_type, -1);
4243 mask = const_binop (LSHIFT_EXPR, mask, size_int (nbitsize - lbitsize), 0);
4244 mask = const_binop (RSHIFT_EXPR, mask,
4245 size_int (nbitsize - lbitsize - lbitpos), 0);
4248 /* If not comparing with constant, just rework the comparison
4250 return fold_build2_loc (loc, code, compare_type,
4251 fold_build2_loc (loc, BIT_AND_EXPR, unsigned_type,
4252 make_bit_field_ref (loc, linner,
4257 fold_build2_loc (loc, BIT_AND_EXPR, unsigned_type,
4258 make_bit_field_ref (loc, rinner,
4264 /* Otherwise, we are handling the constant case. See if the constant is too
4265 big for the field. Warn and return a tree of for 0 (false) if so. We do
4266 this not only for its own sake, but to avoid having to test for this
4267 error case below. If we didn't, we might generate wrong code.
4269 For unsigned fields, the constant shifted right by the field length should
4270 be all zero. For signed fields, the high-order bits should agree with
4275 if (! integer_zerop (const_binop (RSHIFT_EXPR,
4276 fold_convert_loc (loc,
4277 unsigned_type, rhs),
4278 size_int (lbitsize), 0)))
4280 warning (0, "comparison is always %d due to width of bit-field",
4282 return constant_boolean_node (code == NE_EXPR, compare_type);
4287 tree tem = const_binop (RSHIFT_EXPR,
4288 fold_convert_loc (loc, signed_type, rhs),
4289 size_int (lbitsize - 1), 0);
4290 if (! integer_zerop (tem) && ! integer_all_onesp (tem))
4292 warning (0, "comparison is always %d due to width of bit-field",
4294 return constant_boolean_node (code == NE_EXPR, compare_type);
4298 /* Single-bit compares should always be against zero. */
4299 if (lbitsize == 1 && ! integer_zerop (rhs))
4301 code = code == EQ_EXPR ? NE_EXPR : EQ_EXPR;
4302 rhs = build_int_cst (type, 0);
4305 /* Make a new bitfield reference, shift the constant over the
4306 appropriate number of bits and mask it with the computed mask
4307 (in case this was a signed field). If we changed it, make a new one. */
4308 lhs = make_bit_field_ref (loc, linner, unsigned_type, nbitsize, nbitpos, 1);
4311 TREE_SIDE_EFFECTS (lhs) = 1;
4312 TREE_THIS_VOLATILE (lhs) = 1;
4315 rhs = const_binop (BIT_AND_EXPR,
4316 const_binop (LSHIFT_EXPR,
4317 fold_convert_loc (loc, unsigned_type, rhs),
4318 size_int (lbitpos), 0),
4321 lhs = build2 (code, compare_type,
4322 build2 (BIT_AND_EXPR, unsigned_type, lhs, mask),
4324 SET_EXPR_LOCATION (lhs, loc);
4328 /* Subroutine for fold_truthop: decode a field reference.
4330 If EXP is a comparison reference, we return the innermost reference.
4332 *PBITSIZE is set to the number of bits in the reference, *PBITPOS is
4333 set to the starting bit number.
4335 If the innermost field can be completely contained in a mode-sized
4336 unit, *PMODE is set to that mode. Otherwise, it is set to VOIDmode.
4338 *PVOLATILEP is set to 1 if the any expression encountered is volatile;
4339 otherwise it is not changed.
4341 *PUNSIGNEDP is set to the signedness of the field.
4343 *PMASK is set to the mask used. This is either contained in a
4344 BIT_AND_EXPR or derived from the width of the field.
4346 *PAND_MASK is set to the mask found in a BIT_AND_EXPR, if any.
4348 Return 0 if this is not a component reference or is one that we can't
4349 do anything with. */
4352 decode_field_reference (location_t loc, tree exp, HOST_WIDE_INT *pbitsize,
4353 HOST_WIDE_INT *pbitpos, enum machine_mode *pmode,
4354 int *punsignedp, int *pvolatilep,
4355 tree *pmask, tree *pand_mask)
4357 tree outer_type = 0;
4359 tree mask, inner, offset;
4361 unsigned int precision;
4363 /* All the optimizations using this function assume integer fields.
4364 There are problems with FP fields since the type_for_size call
4365 below can fail for, e.g., XFmode. */
4366 if (! INTEGRAL_TYPE_P (TREE_TYPE (exp)))
4369 /* We are interested in the bare arrangement of bits, so strip everything
4370 that doesn't affect the machine mode. However, record the type of the
4371 outermost expression if it may matter below. */
4372 if (CONVERT_EXPR_P (exp)
4373 || TREE_CODE (exp) == NON_LVALUE_EXPR)
4374 outer_type = TREE_TYPE (exp);
4377 if (TREE_CODE (exp) == BIT_AND_EXPR)
4379 and_mask = TREE_OPERAND (exp, 1);
4380 exp = TREE_OPERAND (exp, 0);
4381 STRIP_NOPS (exp); STRIP_NOPS (and_mask);
4382 if (TREE_CODE (and_mask) != INTEGER_CST)
4386 inner = get_inner_reference (exp, pbitsize, pbitpos, &offset, pmode,
4387 punsignedp, pvolatilep, false);
4388 if ((inner == exp && and_mask == 0)
4389 || *pbitsize < 0 || offset != 0
4390 || TREE_CODE (inner) == PLACEHOLDER_EXPR)
4393 /* If the number of bits in the reference is the same as the bitsize of
4394 the outer type, then the outer type gives the signedness. Otherwise
4395 (in case of a small bitfield) the signedness is unchanged. */
4396 if (outer_type && *pbitsize == TYPE_PRECISION (outer_type))
4397 *punsignedp = TYPE_UNSIGNED (outer_type);
4399 /* Compute the mask to access the bitfield. */
4400 unsigned_type = lang_hooks.types.type_for_size (*pbitsize, 1);
4401 precision = TYPE_PRECISION (unsigned_type);
4403 mask = build_int_cst_type (unsigned_type, -1);
4405 mask = const_binop (LSHIFT_EXPR, mask, size_int (precision - *pbitsize), 0);
4406 mask = const_binop (RSHIFT_EXPR, mask, size_int (precision - *pbitsize), 0);
4408 /* Merge it with the mask we found in the BIT_AND_EXPR, if any. */
4410 mask = fold_build2_loc (loc, BIT_AND_EXPR, unsigned_type,
4411 fold_convert_loc (loc, unsigned_type, and_mask), mask);
4414 *pand_mask = and_mask;
4418 /* Return nonzero if MASK represents a mask of SIZE ones in the low-order
4422 all_ones_mask_p (const_tree mask, int size)
4424 tree type = TREE_TYPE (mask);
4425 unsigned int precision = TYPE_PRECISION (type);
4428 tmask = build_int_cst_type (signed_type_for (type), -1);
4431 tree_int_cst_equal (mask,
4432 const_binop (RSHIFT_EXPR,
4433 const_binop (LSHIFT_EXPR, tmask,
4434 size_int (precision - size),
4436 size_int (precision - size), 0));
4439 /* Subroutine for fold: determine if VAL is the INTEGER_CONST that
4440 represents the sign bit of EXP's type. If EXP represents a sign
4441 or zero extension, also test VAL against the unextended type.
4442 The return value is the (sub)expression whose sign bit is VAL,
4443 or NULL_TREE otherwise. */
4446 sign_bit_p (tree exp, const_tree val)
4448 unsigned HOST_WIDE_INT mask_lo, lo;
4449 HOST_WIDE_INT mask_hi, hi;
4453 /* Tree EXP must have an integral type. */
4454 t = TREE_TYPE (exp);
4455 if (! INTEGRAL_TYPE_P (t))
4458 /* Tree VAL must be an integer constant. */
4459 if (TREE_CODE (val) != INTEGER_CST
4460 || TREE_OVERFLOW (val))
4463 width = TYPE_PRECISION (t);
4464 if (width > HOST_BITS_PER_WIDE_INT)
4466 hi = (unsigned HOST_WIDE_INT) 1 << (width - HOST_BITS_PER_WIDE_INT - 1);
4469 mask_hi = ((unsigned HOST_WIDE_INT) -1
4470 >> (2 * HOST_BITS_PER_WIDE_INT - width));
4476 lo = (unsigned HOST_WIDE_INT) 1 << (width - 1);
4479 mask_lo = ((unsigned HOST_WIDE_INT) -1
4480 >> (HOST_BITS_PER_WIDE_INT - width));
4483 /* We mask off those bits beyond TREE_TYPE (exp) so that we can
4484 treat VAL as if it were unsigned. */
4485 if ((TREE_INT_CST_HIGH (val) & mask_hi) == hi
4486 && (TREE_INT_CST_LOW (val) & mask_lo) == lo)
4489 /* Handle extension from a narrower type. */
4490 if (TREE_CODE (exp) == NOP_EXPR
4491 && TYPE_PRECISION (TREE_TYPE (TREE_OPERAND (exp, 0))) < width)
4492 return sign_bit_p (TREE_OPERAND (exp, 0), val);
4497 /* Subroutine for fold_truthop: determine if an operand is simple enough
4498 to be evaluated unconditionally. */
4501 simple_operand_p (const_tree exp)
4503 /* Strip any conversions that don't change the machine mode. */
4506 return (CONSTANT_CLASS_P (exp)
4507 || TREE_CODE (exp) == SSA_NAME
4509 && ! TREE_ADDRESSABLE (exp)
4510 && ! TREE_THIS_VOLATILE (exp)
4511 && ! DECL_NONLOCAL (exp)
4512 /* Don't regard global variables as simple. They may be
4513 allocated in ways unknown to the compiler (shared memory,
4514 #pragma weak, etc). */
4515 && ! TREE_PUBLIC (exp)
4516 && ! DECL_EXTERNAL (exp)
4517 /* Loading a static variable is unduly expensive, but global
4518 registers aren't expensive. */
4519 && (! TREE_STATIC (exp) || DECL_REGISTER (exp))));
4522 /* The following functions are subroutines to fold_range_test and allow it to
4523 try to change a logical combination of comparisons into a range test.
4526 X == 2 || X == 3 || X == 4 || X == 5
4530 (unsigned) (X - 2) <= 3
4532 We describe each set of comparisons as being either inside or outside
4533 a range, using a variable named like IN_P, and then describe the
4534 range with a lower and upper bound. If one of the bounds is omitted,
4535 it represents either the highest or lowest value of the type.
4537 In the comments below, we represent a range by two numbers in brackets
4538 preceded by a "+" to designate being inside that range, or a "-" to
4539 designate being outside that range, so the condition can be inverted by
4540 flipping the prefix. An omitted bound is represented by a "-". For
4541 example, "- [-, 10]" means being outside the range starting at the lowest
4542 possible value and ending at 10, in other words, being greater than 10.
4543 The range "+ [-, -]" is always true and hence the range "- [-, -]" is
4546 We set up things so that the missing bounds are handled in a consistent
4547 manner so neither a missing bound nor "true" and "false" need to be
4548 handled using a special case. */
4550 /* Return the result of applying CODE to ARG0 and ARG1, but handle the case
4551 of ARG0 and/or ARG1 being omitted, meaning an unlimited range. UPPER0_P
4552 and UPPER1_P are nonzero if the respective argument is an upper bound
4553 and zero for a lower. TYPE, if nonzero, is the type of the result; it
4554 must be specified for a comparison. ARG1 will be converted to ARG0's
4555 type if both are specified. */
4558 range_binop (enum tree_code code, tree type, tree arg0, int upper0_p,
4559 tree arg1, int upper1_p)
4565 /* If neither arg represents infinity, do the normal operation.
4566 Else, if not a comparison, return infinity. Else handle the special
4567 comparison rules. Note that most of the cases below won't occur, but
4568 are handled for consistency. */
4570 if (arg0 != 0 && arg1 != 0)
4572 tem = fold_build2 (code, type != 0 ? type : TREE_TYPE (arg0),
4573 arg0, fold_convert (TREE_TYPE (arg0), arg1));
4575 return TREE_CODE (tem) == INTEGER_CST ? tem : 0;
4578 if (TREE_CODE_CLASS (code) != tcc_comparison)
4581 /* Set SGN[01] to -1 if ARG[01] is a lower bound, 1 for upper, and 0
4582 for neither. In real maths, we cannot assume open ended ranges are
4583 the same. But, this is computer arithmetic, where numbers are finite.
4584 We can therefore make the transformation of any unbounded range with
4585 the value Z, Z being greater than any representable number. This permits
4586 us to treat unbounded ranges as equal. */
4587 sgn0 = arg0 != 0 ? 0 : (upper0_p ? 1 : -1);
4588 sgn1 = arg1 != 0 ? 0 : (upper1_p ? 1 : -1);
4592 result = sgn0 == sgn1;
4595 result = sgn0 != sgn1;
4598 result = sgn0 < sgn1;
4601 result = sgn0 <= sgn1;
4604 result = sgn0 > sgn1;
4607 result = sgn0 >= sgn1;
4613 return constant_boolean_node (result, type);
4616 /* Given EXP, a logical expression, set the range it is testing into
4617 variables denoted by PIN_P, PLOW, and PHIGH. Return the expression
4618 actually being tested. *PLOW and *PHIGH will be made of the same
4619 type as the returned expression. If EXP is not a comparison, we
4620 will most likely not be returning a useful value and range. Set
4621 *STRICT_OVERFLOW_P to true if the return value is only valid
4622 because signed overflow is undefined; otherwise, do not change
4623 *STRICT_OVERFLOW_P. */
4626 make_range (tree exp, int *pin_p, tree *plow, tree *phigh,
4627 bool *strict_overflow_p)
4629 enum tree_code code;
4630 tree arg0 = NULL_TREE, arg1 = NULL_TREE;
4631 tree exp_type = NULL_TREE, arg0_type = NULL_TREE;
4633 tree low, high, n_low, n_high;
4634 location_t loc = EXPR_LOCATION (exp);
4636 /* Start with simply saying "EXP != 0" and then look at the code of EXP
4637 and see if we can refine the range. Some of the cases below may not
4638 happen, but it doesn't seem worth worrying about this. We "continue"
4639 the outer loop when we've changed something; otherwise we "break"
4640 the switch, which will "break" the while. */
4643 low = high = build_int_cst (TREE_TYPE (exp), 0);
4647 code = TREE_CODE (exp);
4648 exp_type = TREE_TYPE (exp);
4650 if (IS_EXPR_CODE_CLASS (TREE_CODE_CLASS (code)))
4652 if (TREE_OPERAND_LENGTH (exp) > 0)
4653 arg0 = TREE_OPERAND (exp, 0);
4654 if (TREE_CODE_CLASS (code) == tcc_comparison
4655 || TREE_CODE_CLASS (code) == tcc_unary
4656 || TREE_CODE_CLASS (code) == tcc_binary)
4657 arg0_type = TREE_TYPE (arg0);
4658 if (TREE_CODE_CLASS (code) == tcc_binary
4659 || TREE_CODE_CLASS (code) == tcc_comparison
4660 || (TREE_CODE_CLASS (code) == tcc_expression
4661 && TREE_OPERAND_LENGTH (exp) > 1))
4662 arg1 = TREE_OPERAND (exp, 1);
4667 case TRUTH_NOT_EXPR:
4668 in_p = ! in_p, exp = arg0;
4671 case EQ_EXPR: case NE_EXPR:
4672 case LT_EXPR: case LE_EXPR: case GE_EXPR: case GT_EXPR:
4673 /* We can only do something if the range is testing for zero
4674 and if the second operand is an integer constant. Note that
4675 saying something is "in" the range we make is done by
4676 complementing IN_P since it will set in the initial case of
4677 being not equal to zero; "out" is leaving it alone. */
4678 if (low == 0 || high == 0
4679 || ! integer_zerop (low) || ! integer_zerop (high)
4680 || TREE_CODE (arg1) != INTEGER_CST)
4685 case NE_EXPR: /* - [c, c] */
4688 case EQ_EXPR: /* + [c, c] */
4689 in_p = ! in_p, low = high = arg1;
4691 case GT_EXPR: /* - [-, c] */
4692 low = 0, high = arg1;
4694 case GE_EXPR: /* + [c, -] */
4695 in_p = ! in_p, low = arg1, high = 0;
4697 case LT_EXPR: /* - [c, -] */
4698 low = arg1, high = 0;
4700 case LE_EXPR: /* + [-, c] */
4701 in_p = ! in_p, low = 0, high = arg1;
4707 /* If this is an unsigned comparison, we also know that EXP is
4708 greater than or equal to zero. We base the range tests we make
4709 on that fact, so we record it here so we can parse existing
4710 range tests. We test arg0_type since often the return type
4711 of, e.g. EQ_EXPR, is boolean. */
4712 if (TYPE_UNSIGNED (arg0_type) && (low == 0 || high == 0))
4714 if (! merge_ranges (&n_in_p, &n_low, &n_high,
4716 build_int_cst (arg0_type, 0),
4720 in_p = n_in_p, low = n_low, high = n_high;
4722 /* If the high bound is missing, but we have a nonzero low
4723 bound, reverse the range so it goes from zero to the low bound
4725 if (high == 0 && low && ! integer_zerop (low))
4728 high = range_binop (MINUS_EXPR, NULL_TREE, low, 0,
4729 integer_one_node, 0);
4730 low = build_int_cst (arg0_type, 0);
4738 /* (-x) IN [a,b] -> x in [-b, -a] */
4739 n_low = range_binop (MINUS_EXPR, exp_type,
4740 build_int_cst (exp_type, 0),
4742 n_high = range_binop (MINUS_EXPR, exp_type,
4743 build_int_cst (exp_type, 0),
4745 low = n_low, high = n_high;
4751 exp = build2 (MINUS_EXPR, exp_type, negate_expr (arg0),
4752 build_int_cst (exp_type, 1));
4753 SET_EXPR_LOCATION (exp, loc);
4756 case PLUS_EXPR: case MINUS_EXPR:
4757 if (TREE_CODE (arg1) != INTEGER_CST)
4760 /* If flag_wrapv and ARG0_TYPE is signed, then we cannot
4761 move a constant to the other side. */
4762 if (!TYPE_UNSIGNED (arg0_type)
4763 && !TYPE_OVERFLOW_UNDEFINED (arg0_type))
4766 /* If EXP is signed, any overflow in the computation is undefined,
4767 so we don't worry about it so long as our computations on
4768 the bounds don't overflow. For unsigned, overflow is defined
4769 and this is exactly the right thing. */
4770 n_low = range_binop (code == MINUS_EXPR ? PLUS_EXPR : MINUS_EXPR,
4771 arg0_type, low, 0, arg1, 0);
4772 n_high = range_binop (code == MINUS_EXPR ? PLUS_EXPR : MINUS_EXPR,
4773 arg0_type, high, 1, arg1, 0);
4774 if ((n_low != 0 && TREE_OVERFLOW (n_low))
4775 || (n_high != 0 && TREE_OVERFLOW (n_high)))
4778 if (TYPE_OVERFLOW_UNDEFINED (arg0_type))
4779 *strict_overflow_p = true;
4781 /* Check for an unsigned range which has wrapped around the maximum
4782 value thus making n_high < n_low, and normalize it. */
4783 if (n_low && n_high && tree_int_cst_lt (n_high, n_low))
4785 low = range_binop (PLUS_EXPR, arg0_type, n_high, 0,
4786 integer_one_node, 0);
4787 high = range_binop (MINUS_EXPR, arg0_type, n_low, 0,
4788 integer_one_node, 0);
4790 /* If the range is of the form +/- [ x+1, x ], we won't
4791 be able to normalize it. But then, it represents the
4792 whole range or the empty set, so make it
4794 if (tree_int_cst_equal (n_low, low)
4795 && tree_int_cst_equal (n_high, high))
4801 low = n_low, high = n_high;
4806 CASE_CONVERT: case NON_LVALUE_EXPR:
4807 if (TYPE_PRECISION (arg0_type) > TYPE_PRECISION (exp_type))
4810 if (! INTEGRAL_TYPE_P (arg0_type)
4811 || (low != 0 && ! int_fits_type_p (low, arg0_type))
4812 || (high != 0 && ! int_fits_type_p (high, arg0_type)))
4815 n_low = low, n_high = high;
4818 n_low = fold_convert_loc (loc, arg0_type, n_low);
4821 n_high = fold_convert_loc (loc, arg0_type, n_high);
4824 /* If we're converting arg0 from an unsigned type, to exp,
4825 a signed type, we will be doing the comparison as unsigned.
4826 The tests above have already verified that LOW and HIGH
4829 So we have to ensure that we will handle large unsigned
4830 values the same way that the current signed bounds treat
4833 if (!TYPE_UNSIGNED (exp_type) && TYPE_UNSIGNED (arg0_type))
4837 /* For fixed-point modes, we need to pass the saturating flag
4838 as the 2nd parameter. */
4839 if (ALL_FIXED_POINT_MODE_P (TYPE_MODE (arg0_type)))
4840 equiv_type = lang_hooks.types.type_for_mode
4841 (TYPE_MODE (arg0_type),
4842 TYPE_SATURATING (arg0_type));
4844 equiv_type = lang_hooks.types.type_for_mode
4845 (TYPE_MODE (arg0_type), 1);
4847 /* A range without an upper bound is, naturally, unbounded.
4848 Since convert would have cropped a very large value, use
4849 the max value for the destination type. */
4851 = TYPE_MAX_VALUE (equiv_type) ? TYPE_MAX_VALUE (equiv_type)
4852 : TYPE_MAX_VALUE (arg0_type);
4854 if (TYPE_PRECISION (exp_type) == TYPE_PRECISION (arg0_type))
4855 high_positive = fold_build2_loc (loc, RSHIFT_EXPR, arg0_type,
4856 fold_convert_loc (loc, arg0_type,
4858 build_int_cst (arg0_type, 1));
4860 /* If the low bound is specified, "and" the range with the
4861 range for which the original unsigned value will be
4865 if (! merge_ranges (&n_in_p, &n_low, &n_high,
4866 1, n_low, n_high, 1,
4867 fold_convert_loc (loc, arg0_type,
4872 in_p = (n_in_p == in_p);
4876 /* Otherwise, "or" the range with the range of the input
4877 that will be interpreted as negative. */
4878 if (! merge_ranges (&n_in_p, &n_low, &n_high,
4879 0, n_low, n_high, 1,
4880 fold_convert_loc (loc, arg0_type,
4885 in_p = (in_p != n_in_p);
4890 low = n_low, high = n_high;
4900 /* If EXP is a constant, we can evaluate whether this is true or false. */
4901 if (TREE_CODE (exp) == INTEGER_CST)
4903 in_p = in_p == (integer_onep (range_binop (GE_EXPR, integer_type_node,
4905 && integer_onep (range_binop (LE_EXPR, integer_type_node,
4911 *pin_p = in_p, *plow = low, *phigh = high;
4915 /* Given a range, LOW, HIGH, and IN_P, an expression, EXP, and a result
4916 type, TYPE, return an expression to test if EXP is in (or out of, depending
4917 on IN_P) the range. Return 0 if the test couldn't be created. */
4920 build_range_check (location_t loc, tree type, tree exp, int in_p,
4921 tree low, tree high)
4923 tree etype = TREE_TYPE (exp), value;
4925 #ifdef HAVE_canonicalize_funcptr_for_compare
4926 /* Disable this optimization for function pointer expressions
4927 on targets that require function pointer canonicalization. */
4928 if (HAVE_canonicalize_funcptr_for_compare
4929 && TREE_CODE (etype) == POINTER_TYPE
4930 && TREE_CODE (TREE_TYPE (etype)) == FUNCTION_TYPE)
4936 value = build_range_check (loc, type, exp, 1, low, high);
4938 return invert_truthvalue_loc (loc, value);
4943 if (low == 0 && high == 0)
4944 return build_int_cst (type, 1);
4947 return fold_build2_loc (loc, LE_EXPR, type, exp,
4948 fold_convert_loc (loc, etype, high));
4951 return fold_build2_loc (loc, GE_EXPR, type, exp,
4952 fold_convert_loc (loc, etype, low));
4954 if (operand_equal_p (low, high, 0))
4955 return fold_build2_loc (loc, EQ_EXPR, type, exp,
4956 fold_convert_loc (loc, etype, low));
4958 if (integer_zerop (low))
4960 if (! TYPE_UNSIGNED (etype))
4962 etype = unsigned_type_for (etype);
4963 high = fold_convert_loc (loc, etype, high);
4964 exp = fold_convert_loc (loc, etype, exp);
4966 return build_range_check (loc, type, exp, 1, 0, high);
4969 /* Optimize (c>=1) && (c<=127) into (signed char)c > 0. */
4970 if (integer_onep (low) && TREE_CODE (high) == INTEGER_CST)
4972 unsigned HOST_WIDE_INT lo;
4976 prec = TYPE_PRECISION (etype);
4977 if (prec <= HOST_BITS_PER_WIDE_INT)
4980 lo = ((unsigned HOST_WIDE_INT) 1 << (prec - 1)) - 1;
4984 hi = ((HOST_WIDE_INT) 1 << (prec - HOST_BITS_PER_WIDE_INT - 1)) - 1;
4985 lo = (unsigned HOST_WIDE_INT) -1;
4988 if (TREE_INT_CST_HIGH (high) == hi && TREE_INT_CST_LOW (high) == lo)
4990 if (TYPE_UNSIGNED (etype))
4992 tree signed_etype = signed_type_for (etype);
4993 if (TYPE_PRECISION (signed_etype) != TYPE_PRECISION (etype))
4995 = build_nonstandard_integer_type (TYPE_PRECISION (etype), 0);
4997 etype = signed_etype;
4998 exp = fold_convert_loc (loc, etype, exp);
5000 return fold_build2_loc (loc, GT_EXPR, type, exp,
5001 build_int_cst (etype, 0));
5005 /* Optimize (c>=low) && (c<=high) into (c-low>=0) && (c-low<=high-low).
5006 This requires wrap-around arithmetics for the type of the expression.
5007 First make sure that arithmetics in this type is valid, then make sure
5008 that it wraps around. */
5009 if (TREE_CODE (etype) == ENUMERAL_TYPE || TREE_CODE (etype) == BOOLEAN_TYPE)
5010 etype = lang_hooks.types.type_for_size (TYPE_PRECISION (etype),
5011 TYPE_UNSIGNED (etype));
5013 if (TREE_CODE (etype) == INTEGER_TYPE && !TYPE_OVERFLOW_WRAPS (etype))
5015 tree utype, minv, maxv;
5017 /* Check if (unsigned) INT_MAX + 1 == (unsigned) INT_MIN
5018 for the type in question, as we rely on this here. */
5019 utype = unsigned_type_for (etype);
5020 maxv = fold_convert_loc (loc, utype, TYPE_MAX_VALUE (etype));
5021 maxv = range_binop (PLUS_EXPR, NULL_TREE, maxv, 1,
5022 integer_one_node, 1);
5023 minv = fold_convert_loc (loc, utype, TYPE_MIN_VALUE (etype));
5025 if (integer_zerop (range_binop (NE_EXPR, integer_type_node,
5032 high = fold_convert_loc (loc, etype, high);
5033 low = fold_convert_loc (loc, etype, low);
5034 exp = fold_convert_loc (loc, etype, exp);
5036 value = const_binop (MINUS_EXPR, high, low, 0);
5039 if (POINTER_TYPE_P (etype))
5041 if (value != 0 && !TREE_OVERFLOW (value))
5043 low = fold_convert_loc (loc, sizetype, low);
5044 low = fold_build1_loc (loc, NEGATE_EXPR, sizetype, low);
5045 return build_range_check (loc, type,
5046 fold_build2_loc (loc, POINTER_PLUS_EXPR,
5048 1, build_int_cst (etype, 0), value);
5053 if (value != 0 && !TREE_OVERFLOW (value))
5054 return build_range_check (loc, type,
5055 fold_build2_loc (loc, MINUS_EXPR, etype, exp, low),
5056 1, build_int_cst (etype, 0), value);
5061 /* Return the predecessor of VAL in its type, handling the infinite case. */
5064 range_predecessor (tree val)
5066 tree type = TREE_TYPE (val);
5068 if (INTEGRAL_TYPE_P (type)
5069 && operand_equal_p (val, TYPE_MIN_VALUE (type), 0))
5072 return range_binop (MINUS_EXPR, NULL_TREE, val, 0, integer_one_node, 0);
5075 /* Return the successor of VAL in its type, handling the infinite case. */
5078 range_successor (tree val)
5080 tree type = TREE_TYPE (val);
5082 if (INTEGRAL_TYPE_P (type)
5083 && operand_equal_p (val, TYPE_MAX_VALUE (type), 0))
5086 return range_binop (PLUS_EXPR, NULL_TREE, val, 0, integer_one_node, 0);
5089 /* Given two ranges, see if we can merge them into one. Return 1 if we
5090 can, 0 if we can't. Set the output range into the specified parameters. */
5093 merge_ranges (int *pin_p, tree *plow, tree *phigh, int in0_p, tree low0,
5094 tree high0, int in1_p, tree low1, tree high1)
5102 int lowequal = ((low0 == 0 && low1 == 0)
5103 || integer_onep (range_binop (EQ_EXPR, integer_type_node,
5104 low0, 0, low1, 0)));
5105 int highequal = ((high0 == 0 && high1 == 0)
5106 || integer_onep (range_binop (EQ_EXPR, integer_type_node,
5107 high0, 1, high1, 1)));
5109 /* Make range 0 be the range that starts first, or ends last if they
5110 start at the same value. Swap them if it isn't. */
5111 if (integer_onep (range_binop (GT_EXPR, integer_type_node,
5114 && integer_onep (range_binop (GT_EXPR, integer_type_node,
5115 high1, 1, high0, 1))))
5117 temp = in0_p, in0_p = in1_p, in1_p = temp;
5118 tem = low0, low0 = low1, low1 = tem;
5119 tem = high0, high0 = high1, high1 = tem;
5122 /* Now flag two cases, whether the ranges are disjoint or whether the
5123 second range is totally subsumed in the first. Note that the tests
5124 below are simplified by the ones above. */
5125 no_overlap = integer_onep (range_binop (LT_EXPR, integer_type_node,
5126 high0, 1, low1, 0));
5127 subset = integer_onep (range_binop (LE_EXPR, integer_type_node,
5128 high1, 1, high0, 1));
5130 /* We now have four cases, depending on whether we are including or
5131 excluding the two ranges. */
5134 /* If they don't overlap, the result is false. If the second range
5135 is a subset it is the result. Otherwise, the range is from the start
5136 of the second to the end of the first. */
5138 in_p = 0, low = high = 0;
5140 in_p = 1, low = low1, high = high1;
5142 in_p = 1, low = low1, high = high0;
5145 else if (in0_p && ! in1_p)
5147 /* If they don't overlap, the result is the first range. If they are
5148 equal, the result is false. If the second range is a subset of the
5149 first, and the ranges begin at the same place, we go from just after
5150 the end of the second range to the end of the first. If the second
5151 range is not a subset of the first, or if it is a subset and both
5152 ranges end at the same place, the range starts at the start of the
5153 first range and ends just before the second range.
5154 Otherwise, we can't describe this as a single range. */
5156 in_p = 1, low = low0, high = high0;
5157 else if (lowequal && highequal)
5158 in_p = 0, low = high = 0;
5159 else if (subset && lowequal)
5161 low = range_successor (high1);
5166 /* We are in the weird situation where high0 > high1 but
5167 high1 has no successor. Punt. */
5171 else if (! subset || highequal)
5174 high = range_predecessor (low1);
5178 /* low0 < low1 but low1 has no predecessor. Punt. */
5186 else if (! in0_p && in1_p)
5188 /* If they don't overlap, the result is the second range. If the second
5189 is a subset of the first, the result is false. Otherwise,
5190 the range starts just after the first range and ends at the
5191 end of the second. */
5193 in_p = 1, low = low1, high = high1;
5194 else if (subset || highequal)
5195 in_p = 0, low = high = 0;
5198 low = range_successor (high0);
5203 /* high1 > high0 but high0 has no successor. Punt. */
5211 /* The case where we are excluding both ranges. Here the complex case
5212 is if they don't overlap. In that case, the only time we have a
5213 range is if they are adjacent. If the second is a subset of the
5214 first, the result is the first. Otherwise, the range to exclude
5215 starts at the beginning of the first range and ends at the end of the
5219 if (integer_onep (range_binop (EQ_EXPR, integer_type_node,
5220 range_successor (high0),
5222 in_p = 0, low = low0, high = high1;
5225 /* Canonicalize - [min, x] into - [-, x]. */
5226 if (low0 && TREE_CODE (low0) == INTEGER_CST)
5227 switch (TREE_CODE (TREE_TYPE (low0)))
5230 if (TYPE_PRECISION (TREE_TYPE (low0))
5231 != GET_MODE_BITSIZE (TYPE_MODE (TREE_TYPE (low0))))
5235 if (tree_int_cst_equal (low0,
5236 TYPE_MIN_VALUE (TREE_TYPE (low0))))
5240 if (TYPE_UNSIGNED (TREE_TYPE (low0))
5241 && integer_zerop (low0))
5248 /* Canonicalize - [x, max] into - [x, -]. */
5249 if (high1 && TREE_CODE (high1) == INTEGER_CST)
5250 switch (TREE_CODE (TREE_TYPE (high1)))
5253 if (TYPE_PRECISION (TREE_TYPE (high1))
5254 != GET_MODE_BITSIZE (TYPE_MODE (TREE_TYPE (high1))))
5258 if (tree_int_cst_equal (high1,
5259 TYPE_MAX_VALUE (TREE_TYPE (high1))))
5263 if (TYPE_UNSIGNED (TREE_TYPE (high1))
5264 && integer_zerop (range_binop (PLUS_EXPR, NULL_TREE,
5266 integer_one_node, 1)))
5273 /* The ranges might be also adjacent between the maximum and
5274 minimum values of the given type. For
5275 - [{min,-}, x] and - [y, {max,-}] ranges where x + 1 < y
5276 return + [x + 1, y - 1]. */
5277 if (low0 == 0 && high1 == 0)
5279 low = range_successor (high0);
5280 high = range_predecessor (low1);
5281 if (low == 0 || high == 0)
5291 in_p = 0, low = low0, high = high0;
5293 in_p = 0, low = low0, high = high1;
5296 *pin_p = in_p, *plow = low, *phigh = high;
5301 /* Subroutine of fold, looking inside expressions of the form
5302 A op B ? A : C, where ARG0, ARG1 and ARG2 are the three operands
5303 of the COND_EXPR. This function is being used also to optimize
5304 A op B ? C : A, by reversing the comparison first.
5306 Return a folded expression whose code is not a COND_EXPR
5307 anymore, or NULL_TREE if no folding opportunity is found. */
5310 fold_cond_expr_with_comparison (location_t loc, tree type,
5311 tree arg0, tree arg1, tree arg2)
5313 enum tree_code comp_code = TREE_CODE (arg0);
5314 tree arg00 = TREE_OPERAND (arg0, 0);
5315 tree arg01 = TREE_OPERAND (arg0, 1);
5316 tree arg1_type = TREE_TYPE (arg1);
5322 /* If we have A op 0 ? A : -A, consider applying the following
5325 A == 0? A : -A same as -A
5326 A != 0? A : -A same as A
5327 A >= 0? A : -A same as abs (A)
5328 A > 0? A : -A same as abs (A)
5329 A <= 0? A : -A same as -abs (A)
5330 A < 0? A : -A same as -abs (A)
5332 None of these transformations work for modes with signed
5333 zeros. If A is +/-0, the first two transformations will
5334 change the sign of the result (from +0 to -0, or vice
5335 versa). The last four will fix the sign of the result,
5336 even though the original expressions could be positive or
5337 negative, depending on the sign of A.
5339 Note that all these transformations are correct if A is
5340 NaN, since the two alternatives (A and -A) are also NaNs. */
5341 if (!HONOR_SIGNED_ZEROS (TYPE_MODE (type))
5342 && (FLOAT_TYPE_P (TREE_TYPE (arg01))
5343 ? real_zerop (arg01)
5344 : integer_zerop (arg01))
5345 && ((TREE_CODE (arg2) == NEGATE_EXPR
5346 && operand_equal_p (TREE_OPERAND (arg2, 0), arg1, 0))
5347 /* In the case that A is of the form X-Y, '-A' (arg2) may
5348 have already been folded to Y-X, check for that. */
5349 || (TREE_CODE (arg1) == MINUS_EXPR
5350 && TREE_CODE (arg2) == MINUS_EXPR
5351 && operand_equal_p (TREE_OPERAND (arg1, 0),
5352 TREE_OPERAND (arg2, 1), 0)
5353 && operand_equal_p (TREE_OPERAND (arg1, 1),
5354 TREE_OPERAND (arg2, 0), 0))))
5359 tem = fold_convert_loc (loc, arg1_type, arg1);
5360 return pedantic_non_lvalue_loc (loc,
5361 fold_convert_loc (loc, type,
5362 negate_expr (tem)));
5365 return pedantic_non_lvalue_loc (loc, fold_convert_loc (loc, type, arg1));
5368 if (flag_trapping_math)
5373 if (TYPE_UNSIGNED (TREE_TYPE (arg1)))
5374 arg1 = fold_convert_loc (loc, signed_type_for
5375 (TREE_TYPE (arg1)), arg1);
5376 tem = fold_build1_loc (loc, ABS_EXPR, TREE_TYPE (arg1), arg1);
5377 return pedantic_non_lvalue_loc (loc, fold_convert_loc (loc, type, tem));
5380 if (flag_trapping_math)
5384 if (TYPE_UNSIGNED (TREE_TYPE (arg1)))
5385 arg1 = fold_convert_loc (loc, signed_type_for
5386 (TREE_TYPE (arg1)), arg1);
5387 tem = fold_build1_loc (loc, ABS_EXPR, TREE_TYPE (arg1), arg1);
5388 return negate_expr (fold_convert_loc (loc, type, tem));
5390 gcc_assert (TREE_CODE_CLASS (comp_code) == tcc_comparison);
5394 /* A != 0 ? A : 0 is simply A, unless A is -0. Likewise
5395 A == 0 ? A : 0 is always 0 unless A is -0. Note that
5396 both transformations are correct when A is NaN: A != 0
5397 is then true, and A == 0 is false. */
5399 if (!HONOR_SIGNED_ZEROS (TYPE_MODE (type))
5400 && integer_zerop (arg01) && integer_zerop (arg2))
5402 if (comp_code == NE_EXPR)
5403 return pedantic_non_lvalue_loc (loc, fold_convert_loc (loc, type, arg1));
5404 else if (comp_code == EQ_EXPR)
5405 return build_int_cst (type, 0);
5408 /* Try some transformations of A op B ? A : B.
5410 A == B? A : B same as B
5411 A != B? A : B same as A
5412 A >= B? A : B same as max (A, B)
5413 A > B? A : B same as max (B, A)
5414 A <= B? A : B same as min (A, B)
5415 A < B? A : B same as min (B, A)
5417 As above, these transformations don't work in the presence
5418 of signed zeros. For example, if A and B are zeros of
5419 opposite sign, the first two transformations will change
5420 the sign of the result. In the last four, the original
5421 expressions give different results for (A=+0, B=-0) and
5422 (A=-0, B=+0), but the transformed expressions do not.
5424 The first two transformations are correct if either A or B
5425 is a NaN. In the first transformation, the condition will
5426 be false, and B will indeed be chosen. In the case of the
5427 second transformation, the condition A != B will be true,
5428 and A will be chosen.
5430 The conversions to max() and min() are not correct if B is
5431 a number and A is not. The conditions in the original
5432 expressions will be false, so all four give B. The min()
5433 and max() versions would give a NaN instead. */
5434 if (!HONOR_SIGNED_ZEROS (TYPE_MODE (type))
5435 && operand_equal_for_comparison_p (arg01, arg2, arg00)
5436 /* Avoid these transformations if the COND_EXPR may be used
5437 as an lvalue in the C++ front-end. PR c++/19199. */
5439 || (strcmp (lang_hooks.name, "GNU C++") != 0
5440 && strcmp (lang_hooks.name, "GNU Objective-C++") != 0)
5441 || ! maybe_lvalue_p (arg1)
5442 || ! maybe_lvalue_p (arg2)))
5444 tree comp_op0 = arg00;
5445 tree comp_op1 = arg01;
5446 tree comp_type = TREE_TYPE (comp_op0);
5448 /* Avoid adding NOP_EXPRs in case this is an lvalue. */
5449 if (TYPE_MAIN_VARIANT (comp_type) == TYPE_MAIN_VARIANT (type))
5459 return pedantic_non_lvalue_loc (loc, fold_convert_loc (loc, type, arg2));
5461 return pedantic_non_lvalue_loc (loc, fold_convert_loc (loc, type, arg1));
5466 /* In C++ a ?: expression can be an lvalue, so put the
5467 operand which will be used if they are equal first
5468 so that we can convert this back to the
5469 corresponding COND_EXPR. */
5470 if (!HONOR_NANS (TYPE_MODE (TREE_TYPE (arg1))))
5472 comp_op0 = fold_convert_loc (loc, comp_type, comp_op0);
5473 comp_op1 = fold_convert_loc (loc, comp_type, comp_op1);
5474 tem = (comp_code == LE_EXPR || comp_code == UNLE_EXPR)
5475 ? fold_build2_loc (loc, MIN_EXPR, comp_type, comp_op0, comp_op1)
5476 : fold_build2_loc (loc, MIN_EXPR, comp_type,
5477 comp_op1, comp_op0);
5478 return pedantic_non_lvalue_loc (loc,
5479 fold_convert_loc (loc, type, tem));
5486 if (!HONOR_NANS (TYPE_MODE (TREE_TYPE (arg1))))
5488 comp_op0 = fold_convert_loc (loc, comp_type, comp_op0);
5489 comp_op1 = fold_convert_loc (loc, comp_type, comp_op1);
5490 tem = (comp_code == GE_EXPR || comp_code == UNGE_EXPR)
5491 ? fold_build2_loc (loc, MAX_EXPR, comp_type, comp_op0, comp_op1)
5492 : fold_build2_loc (loc, MAX_EXPR, comp_type,
5493 comp_op1, comp_op0);
5494 return pedantic_non_lvalue_loc (loc,
5495 fold_convert_loc (loc, type, tem));
5499 if (!HONOR_NANS (TYPE_MODE (TREE_TYPE (arg1))))
5500 return pedantic_non_lvalue_loc (loc,
5501 fold_convert_loc (loc, type, arg2));
5504 if (!HONOR_NANS (TYPE_MODE (TREE_TYPE (arg1))))
5505 return pedantic_non_lvalue_loc (loc,
5506 fold_convert_loc (loc, type, arg1));
5509 gcc_assert (TREE_CODE_CLASS (comp_code) == tcc_comparison);
5514 /* If this is A op C1 ? A : C2 with C1 and C2 constant integers,
5515 we might still be able to simplify this. For example,
5516 if C1 is one less or one more than C2, this might have started
5517 out as a MIN or MAX and been transformed by this function.
5518 Only good for INTEGER_TYPEs, because we need TYPE_MAX_VALUE. */
5520 if (INTEGRAL_TYPE_P (type)
5521 && TREE_CODE (arg01) == INTEGER_CST
5522 && TREE_CODE (arg2) == INTEGER_CST)
5526 if (TREE_CODE (arg1) == INTEGER_CST)
5528 /* We can replace A with C1 in this case. */
5529 arg1 = fold_convert_loc (loc, type, arg01);
5530 return fold_build3_loc (loc, COND_EXPR, type, arg0, arg1, arg2);
5533 /* If C1 is C2 + 1, this is min(A, C2), but use ARG00's type for
5534 MIN_EXPR, to preserve the signedness of the comparison. */
5535 if (! operand_equal_p (arg2, TYPE_MAX_VALUE (type),
5537 && operand_equal_p (arg01,
5538 const_binop (PLUS_EXPR, arg2,
5539 build_int_cst (type, 1), 0),
5542 tem = fold_build2_loc (loc, MIN_EXPR, TREE_TYPE (arg00), arg00,
5543 fold_convert_loc (loc, TREE_TYPE (arg00),
5545 return pedantic_non_lvalue_loc (loc,
5546 fold_convert_loc (loc, type, tem));
5551 /* If C1 is C2 - 1, this is min(A, C2), with the same care
5553 if (! operand_equal_p (arg2, TYPE_MIN_VALUE (type),
5555 && operand_equal_p (arg01,
5556 const_binop (MINUS_EXPR, arg2,
5557 build_int_cst (type, 1), 0),
5560 tem = fold_build2_loc (loc, MIN_EXPR, TREE_TYPE (arg00), arg00,
5561 fold_convert_loc (loc, TREE_TYPE (arg00),
5563 return pedantic_non_lvalue_loc (loc,
5564 fold_convert_loc (loc, type, tem));
5569 /* If C1 is C2 - 1, this is max(A, C2), but use ARG00's type for
5570 MAX_EXPR, to preserve the signedness of the comparison. */
5571 if (! operand_equal_p (arg2, TYPE_MIN_VALUE (type),
5573 && operand_equal_p (arg01,
5574 const_binop (MINUS_EXPR, arg2,
5575 build_int_cst (type, 1), 0),
5578 tem = fold_build2_loc (loc, MAX_EXPR, TREE_TYPE (arg00), arg00,
5579 fold_convert_loc (loc, TREE_TYPE (arg00),
5581 return pedantic_non_lvalue_loc (loc, fold_convert_loc (loc, type, tem));
5586 /* If C1 is C2 + 1, this is max(A, C2), with the same care as above. */
5587 if (! operand_equal_p (arg2, TYPE_MAX_VALUE (type),
5589 && operand_equal_p (arg01,
5590 const_binop (PLUS_EXPR, arg2,
5591 build_int_cst (type, 1), 0),
5594 tem = fold_build2_loc (loc, MAX_EXPR, TREE_TYPE (arg00), arg00,
5595 fold_convert_loc (loc, TREE_TYPE (arg00),
5597 return pedantic_non_lvalue_loc (loc, fold_convert_loc (loc, type, tem));
5611 #ifndef LOGICAL_OP_NON_SHORT_CIRCUIT
5612 #define LOGICAL_OP_NON_SHORT_CIRCUIT \
5613 (BRANCH_COST (optimize_function_for_speed_p (cfun), \
5617 /* EXP is some logical combination of boolean tests. See if we can
5618 merge it into some range test. Return the new tree if so. */
5621 fold_range_test (location_t loc, enum tree_code code, tree type,
5624 int or_op = (code == TRUTH_ORIF_EXPR
5625 || code == TRUTH_OR_EXPR);
5626 int in0_p, in1_p, in_p;
5627 tree low0, low1, low, high0, high1, high;
5628 bool strict_overflow_p = false;
5629 tree lhs = make_range (op0, &in0_p, &low0, &high0, &strict_overflow_p);
5630 tree rhs = make_range (op1, &in1_p, &low1, &high1, &strict_overflow_p);
5632 const char * const warnmsg = G_("assuming signed overflow does not occur "
5633 "when simplifying range test");
5635 /* If this is an OR operation, invert both sides; we will invert
5636 again at the end. */
5638 in0_p = ! in0_p, in1_p = ! in1_p;
5640 /* If both expressions are the same, if we can merge the ranges, and we
5641 can build the range test, return it or it inverted. If one of the
5642 ranges is always true or always false, consider it to be the same
5643 expression as the other. */
5644 if ((lhs == 0 || rhs == 0 || operand_equal_p (lhs, rhs, 0))
5645 && merge_ranges (&in_p, &low, &high, in0_p, low0, high0,
5647 && 0 != (tem = (build_range_check (UNKNOWN_LOCATION, type,
5649 : rhs != 0 ? rhs : integer_zero_node,
5652 if (strict_overflow_p)
5653 fold_overflow_warning (warnmsg, WARN_STRICT_OVERFLOW_COMPARISON);
5654 return or_op ? invert_truthvalue_loc (loc, tem) : tem;
5657 /* On machines where the branch cost is expensive, if this is a
5658 short-circuited branch and the underlying object on both sides
5659 is the same, make a non-short-circuit operation. */
5660 else if (LOGICAL_OP_NON_SHORT_CIRCUIT
5661 && lhs != 0 && rhs != 0
5662 && (code == TRUTH_ANDIF_EXPR
5663 || code == TRUTH_ORIF_EXPR)
5664 && operand_equal_p (lhs, rhs, 0))
5666 /* If simple enough, just rewrite. Otherwise, make a SAVE_EXPR
5667 unless we are at top level or LHS contains a PLACEHOLDER_EXPR, in
5668 which cases we can't do this. */
5669 if (simple_operand_p (lhs))
5671 tem = build2 (code == TRUTH_ANDIF_EXPR
5672 ? TRUTH_AND_EXPR : TRUTH_OR_EXPR,
5674 SET_EXPR_LOCATION (tem, loc);
5678 else if (lang_hooks.decls.global_bindings_p () == 0
5679 && ! CONTAINS_PLACEHOLDER_P (lhs))
5681 tree common = save_expr (lhs);
5683 if (0 != (lhs = build_range_check (loc, type, common,
5684 or_op ? ! in0_p : in0_p,
5686 && (0 != (rhs = build_range_check (loc, type, common,
5687 or_op ? ! in1_p : in1_p,
5690 if (strict_overflow_p)
5691 fold_overflow_warning (warnmsg,
5692 WARN_STRICT_OVERFLOW_COMPARISON);
5693 tem = build2 (code == TRUTH_ANDIF_EXPR
5694 ? TRUTH_AND_EXPR : TRUTH_OR_EXPR,
5696 SET_EXPR_LOCATION (tem, loc);
5705 /* Subroutine for fold_truthop: C is an INTEGER_CST interpreted as a P
5706 bit value. Arrange things so the extra bits will be set to zero if and
5707 only if C is signed-extended to its full width. If MASK is nonzero,
5708 it is an INTEGER_CST that should be AND'ed with the extra bits. */
5711 unextend (tree c, int p, int unsignedp, tree mask)
5713 tree type = TREE_TYPE (c);
5714 int modesize = GET_MODE_BITSIZE (TYPE_MODE (type));
5717 if (p == modesize || unsignedp)
5720 /* We work by getting just the sign bit into the low-order bit, then
5721 into the high-order bit, then sign-extend. We then XOR that value
5723 temp = const_binop (RSHIFT_EXPR, c, size_int (p - 1), 0);
5724 temp = const_binop (BIT_AND_EXPR, temp, size_int (1), 0);
5726 /* We must use a signed type in order to get an arithmetic right shift.
5727 However, we must also avoid introducing accidental overflows, so that
5728 a subsequent call to integer_zerop will work. Hence we must
5729 do the type conversion here. At this point, the constant is either
5730 zero or one, and the conversion to a signed type can never overflow.
5731 We could get an overflow if this conversion is done anywhere else. */
5732 if (TYPE_UNSIGNED (type))
5733 temp = fold_convert (signed_type_for (type), temp);
5735 temp = const_binop (LSHIFT_EXPR, temp, size_int (modesize - 1), 0);
5736 temp = const_binop (RSHIFT_EXPR, temp, size_int (modesize - p - 1), 0);
5738 temp = const_binop (BIT_AND_EXPR, temp,
5739 fold_convert (TREE_TYPE (c), mask),
5741 /* If necessary, convert the type back to match the type of C. */
5742 if (TYPE_UNSIGNED (type))
5743 temp = fold_convert (type, temp);
5745 return fold_convert (type,
5746 const_binop (BIT_XOR_EXPR, c, temp, 0));
5749 /* Find ways of folding logical expressions of LHS and RHS:
5750 Try to merge two comparisons to the same innermost item.
5751 Look for range tests like "ch >= '0' && ch <= '9'".
5752 Look for combinations of simple terms on machines with expensive branches
5753 and evaluate the RHS unconditionally.
5755 For example, if we have p->a == 2 && p->b == 4 and we can make an
5756 object large enough to span both A and B, we can do this with a comparison
5757 against the object ANDed with the a mask.
5759 If we have p->a == q->a && p->b == q->b, we may be able to use bit masking
5760 operations to do this with one comparison.
5762 We check for both normal comparisons and the BIT_AND_EXPRs made this by
5763 function and the one above.
5765 CODE is the logical operation being done. It can be TRUTH_ANDIF_EXPR,
5766 TRUTH_AND_EXPR, TRUTH_ORIF_EXPR, or TRUTH_OR_EXPR.
5768 TRUTH_TYPE is the type of the logical operand and LHS and RHS are its
5771 We return the simplified tree or 0 if no optimization is possible. */
5774 fold_truthop (location_t loc, enum tree_code code, tree truth_type,
5777 /* If this is the "or" of two comparisons, we can do something if
5778 the comparisons are NE_EXPR. If this is the "and", we can do something
5779 if the comparisons are EQ_EXPR. I.e.,
5780 (a->b == 2 && a->c == 4) can become (a->new == NEW).
5782 WANTED_CODE is this operation code. For single bit fields, we can
5783 convert EQ_EXPR to NE_EXPR so we need not reject the "wrong"
5784 comparison for one-bit fields. */
5786 enum tree_code wanted_code;
5787 enum tree_code lcode, rcode;
5788 tree ll_arg, lr_arg, rl_arg, rr_arg;
5789 tree ll_inner, lr_inner, rl_inner, rr_inner;
5790 HOST_WIDE_INT ll_bitsize, ll_bitpos, lr_bitsize, lr_bitpos;
5791 HOST_WIDE_INT rl_bitsize, rl_bitpos, rr_bitsize, rr_bitpos;
5792 HOST_WIDE_INT xll_bitpos, xlr_bitpos, xrl_bitpos, xrr_bitpos;
5793 HOST_WIDE_INT lnbitsize, lnbitpos, rnbitsize, rnbitpos;
5794 int ll_unsignedp, lr_unsignedp, rl_unsignedp, rr_unsignedp;
5795 enum machine_mode ll_mode, lr_mode, rl_mode, rr_mode;
5796 enum machine_mode lnmode, rnmode;
5797 tree ll_mask, lr_mask, rl_mask, rr_mask;
5798 tree ll_and_mask, lr_and_mask, rl_and_mask, rr_and_mask;
5799 tree l_const, r_const;
5800 tree lntype, rntype, result;
5801 HOST_WIDE_INT first_bit, end_bit;
5803 tree orig_lhs = lhs, orig_rhs = rhs;
5804 enum tree_code orig_code = code;
5806 /* Start by getting the comparison codes. Fail if anything is volatile.
5807 If one operand is a BIT_AND_EXPR with the constant one, treat it as if
5808 it were surrounded with a NE_EXPR. */
5810 if (TREE_SIDE_EFFECTS (lhs) || TREE_SIDE_EFFECTS (rhs))
5813 lcode = TREE_CODE (lhs);
5814 rcode = TREE_CODE (rhs);
5816 if (lcode == BIT_AND_EXPR && integer_onep (TREE_OPERAND (lhs, 1)))
5818 lhs = build2 (NE_EXPR, truth_type, lhs,
5819 build_int_cst (TREE_TYPE (lhs), 0));
5823 if (rcode == BIT_AND_EXPR && integer_onep (TREE_OPERAND (rhs, 1)))
5825 rhs = build2 (NE_EXPR, truth_type, rhs,
5826 build_int_cst (TREE_TYPE (rhs), 0));
5830 if (TREE_CODE_CLASS (lcode) != tcc_comparison
5831 || TREE_CODE_CLASS (rcode) != tcc_comparison)
5834 ll_arg = TREE_OPERAND (lhs, 0);
5835 lr_arg = TREE_OPERAND (lhs, 1);
5836 rl_arg = TREE_OPERAND (rhs, 0);
5837 rr_arg = TREE_OPERAND (rhs, 1);
5839 /* Simplify (x<y) && (x==y) into (x<=y) and related optimizations. */
5840 if (simple_operand_p (ll_arg)
5841 && simple_operand_p (lr_arg))
5844 if (operand_equal_p (ll_arg, rl_arg, 0)
5845 && operand_equal_p (lr_arg, rr_arg, 0))
5847 result = combine_comparisons (loc, code, lcode, rcode,
5848 truth_type, ll_arg, lr_arg);
5852 else if (operand_equal_p (ll_arg, rr_arg, 0)
5853 && operand_equal_p (lr_arg, rl_arg, 0))
5855 result = combine_comparisons (loc, code, lcode,
5856 swap_tree_comparison (rcode),
5857 truth_type, ll_arg, lr_arg);
5863 code = ((code == TRUTH_AND_EXPR || code == TRUTH_ANDIF_EXPR)
5864 ? TRUTH_AND_EXPR : TRUTH_OR_EXPR);
5866 /* If the RHS can be evaluated unconditionally and its operands are
5867 simple, it wins to evaluate the RHS unconditionally on machines
5868 with expensive branches. In this case, this isn't a comparison
5869 that can be merged. Avoid doing this if the RHS is a floating-point
5870 comparison since those can trap. */
5872 if (BRANCH_COST (optimize_function_for_speed_p (cfun),
5874 && ! FLOAT_TYPE_P (TREE_TYPE (rl_arg))
5875 && simple_operand_p (rl_arg)
5876 && simple_operand_p (rr_arg))
5878 /* Convert (a != 0) || (b != 0) into (a | b) != 0. */
5879 if (code == TRUTH_OR_EXPR
5880 && lcode == NE_EXPR && integer_zerop (lr_arg)
5881 && rcode == NE_EXPR && integer_zerop (rr_arg)
5882 && TREE_TYPE (ll_arg) == TREE_TYPE (rl_arg)
5883 && INTEGRAL_TYPE_P (TREE_TYPE (ll_arg)))
5885 result = build2 (NE_EXPR, truth_type,
5886 build2 (BIT_IOR_EXPR, TREE_TYPE (ll_arg),
5888 build_int_cst (TREE_TYPE (ll_arg), 0));
5889 goto fold_truthop_exit;
5892 /* Convert (a == 0) && (b == 0) into (a | b) == 0. */
5893 if (code == TRUTH_AND_EXPR
5894 && lcode == EQ_EXPR && integer_zerop (lr_arg)
5895 && rcode == EQ_EXPR && integer_zerop (rr_arg)
5896 && TREE_TYPE (ll_arg) == TREE_TYPE (rl_arg)
5897 && INTEGRAL_TYPE_P (TREE_TYPE (ll_arg)))
5899 result = build2 (EQ_EXPR, truth_type,
5900 build2 (BIT_IOR_EXPR, TREE_TYPE (ll_arg),
5902 build_int_cst (TREE_TYPE (ll_arg), 0));
5903 goto fold_truthop_exit;
5906 if (LOGICAL_OP_NON_SHORT_CIRCUIT)
5908 if (code != orig_code || lhs != orig_lhs || rhs != orig_rhs)
5910 result = build2 (code, truth_type, lhs, rhs);
5911 goto fold_truthop_exit;
5917 /* See if the comparisons can be merged. Then get all the parameters for
5920 if ((lcode != EQ_EXPR && lcode != NE_EXPR)
5921 || (rcode != EQ_EXPR && rcode != NE_EXPR))
5925 ll_inner = decode_field_reference (loc, ll_arg,
5926 &ll_bitsize, &ll_bitpos, &ll_mode,
5927 &ll_unsignedp, &volatilep, &ll_mask,
5929 lr_inner = decode_field_reference (loc, lr_arg,
5930 &lr_bitsize, &lr_bitpos, &lr_mode,
5931 &lr_unsignedp, &volatilep, &lr_mask,
5933 rl_inner = decode_field_reference (loc, rl_arg,
5934 &rl_bitsize, &rl_bitpos, &rl_mode,
5935 &rl_unsignedp, &volatilep, &rl_mask,
5937 rr_inner = decode_field_reference (loc, rr_arg,
5938 &rr_bitsize, &rr_bitpos, &rr_mode,
5939 &rr_unsignedp, &volatilep, &rr_mask,
5942 /* It must be true that the inner operation on the lhs of each
5943 comparison must be the same if we are to be able to do anything.
5944 Then see if we have constants. If not, the same must be true for
5946 if (volatilep || ll_inner == 0 || rl_inner == 0
5947 || ! operand_equal_p (ll_inner, rl_inner, 0))
5950 if (TREE_CODE (lr_arg) == INTEGER_CST
5951 && TREE_CODE (rr_arg) == INTEGER_CST)
5952 l_const = lr_arg, r_const = rr_arg;
5953 else if (lr_inner == 0 || rr_inner == 0
5954 || ! operand_equal_p (lr_inner, rr_inner, 0))
5957 l_const = r_const = 0;
5959 /* If either comparison code is not correct for our logical operation,
5960 fail. However, we can convert a one-bit comparison against zero into
5961 the opposite comparison against that bit being set in the field. */
5963 wanted_code = (code == TRUTH_AND_EXPR ? EQ_EXPR : NE_EXPR);
5964 if (lcode != wanted_code)
5966 if (l_const && integer_zerop (l_const) && integer_pow2p (ll_mask))
5968 /* Make the left operand unsigned, since we are only interested
5969 in the value of one bit. Otherwise we are doing the wrong
5978 /* This is analogous to the code for l_const above. */
5979 if (rcode != wanted_code)
5981 if (r_const && integer_zerop (r_const) && integer_pow2p (rl_mask))
5990 /* See if we can find a mode that contains both fields being compared on
5991 the left. If we can't, fail. Otherwise, update all constants and masks
5992 to be relative to a field of that size. */
5993 first_bit = MIN (ll_bitpos, rl_bitpos);
5994 end_bit = MAX (ll_bitpos + ll_bitsize, rl_bitpos + rl_bitsize);
5995 lnmode = get_best_mode (end_bit - first_bit, first_bit,
5996 TYPE_ALIGN (TREE_TYPE (ll_inner)), word_mode,
5998 if (lnmode == VOIDmode)
6001 lnbitsize = GET_MODE_BITSIZE (lnmode);
6002 lnbitpos = first_bit & ~ (lnbitsize - 1);
6003 lntype = lang_hooks.types.type_for_size (lnbitsize, 1);
6004 xll_bitpos = ll_bitpos - lnbitpos, xrl_bitpos = rl_bitpos - lnbitpos;
6006 if (BYTES_BIG_ENDIAN)
6008 xll_bitpos = lnbitsize - xll_bitpos - ll_bitsize;
6009 xrl_bitpos = lnbitsize - xrl_bitpos - rl_bitsize;
6012 ll_mask = const_binop (LSHIFT_EXPR, fold_convert_loc (loc, lntype, ll_mask),
6013 size_int (xll_bitpos), 0);
6014 rl_mask = const_binop (LSHIFT_EXPR, fold_convert_loc (loc, lntype, rl_mask),
6015 size_int (xrl_bitpos), 0);
6019 l_const = fold_convert_loc (loc, lntype, l_const);
6020 l_const = unextend (l_const, ll_bitsize, ll_unsignedp, ll_and_mask);
6021 l_const = const_binop (LSHIFT_EXPR, l_const, size_int (xll_bitpos), 0);
6022 if (! integer_zerop (const_binop (BIT_AND_EXPR, l_const,
6023 fold_build1_loc (loc, BIT_NOT_EXPR,
6027 warning (0, "comparison is always %d", wanted_code == NE_EXPR);
6029 return constant_boolean_node (wanted_code == NE_EXPR, truth_type);
6034 r_const = fold_convert_loc (loc, lntype, r_const);
6035 r_const = unextend (r_const, rl_bitsize, rl_unsignedp, rl_and_mask);
6036 r_const = const_binop (LSHIFT_EXPR, r_const, size_int (xrl_bitpos), 0);
6037 if (! integer_zerop (const_binop (BIT_AND_EXPR, r_const,
6038 fold_build1_loc (loc, BIT_NOT_EXPR,
6042 warning (0, "comparison is always %d", wanted_code == NE_EXPR);
6044 return constant_boolean_node (wanted_code == NE_EXPR, truth_type);
6048 /* If the right sides are not constant, do the same for it. Also,
6049 disallow this optimization if a size or signedness mismatch occurs
6050 between the left and right sides. */
6053 if (ll_bitsize != lr_bitsize || rl_bitsize != rr_bitsize
6054 || ll_unsignedp != lr_unsignedp || rl_unsignedp != rr_unsignedp
6055 /* Make sure the two fields on the right
6056 correspond to the left without being swapped. */
6057 || ll_bitpos - rl_bitpos != lr_bitpos - rr_bitpos)
6060 first_bit = MIN (lr_bitpos, rr_bitpos);
6061 end_bit = MAX (lr_bitpos + lr_bitsize, rr_bitpos + rr_bitsize);
6062 rnmode = get_best_mode (end_bit - first_bit, first_bit,
6063 TYPE_ALIGN (TREE_TYPE (lr_inner)), word_mode,
6065 if (rnmode == VOIDmode)
6068 rnbitsize = GET_MODE_BITSIZE (rnmode);
6069 rnbitpos = first_bit & ~ (rnbitsize - 1);
6070 rntype = lang_hooks.types.type_for_size (rnbitsize, 1);
6071 xlr_bitpos = lr_bitpos - rnbitpos, xrr_bitpos = rr_bitpos - rnbitpos;
6073 if (BYTES_BIG_ENDIAN)
6075 xlr_bitpos = rnbitsize - xlr_bitpos - lr_bitsize;
6076 xrr_bitpos = rnbitsize - xrr_bitpos - rr_bitsize;
6079 lr_mask = const_binop (LSHIFT_EXPR, fold_convert_loc (loc,
6081 size_int (xlr_bitpos), 0);
6082 rr_mask = const_binop (LSHIFT_EXPR, fold_convert_loc (loc,
6084 size_int (xrr_bitpos), 0);
6086 /* Make a mask that corresponds to both fields being compared.
6087 Do this for both items being compared. If the operands are the
6088 same size and the bits being compared are in the same position
6089 then we can do this by masking both and comparing the masked
6091 ll_mask = const_binop (BIT_IOR_EXPR, ll_mask, rl_mask, 0);
6092 lr_mask = const_binop (BIT_IOR_EXPR, lr_mask, rr_mask, 0);
6093 if (lnbitsize == rnbitsize && xll_bitpos == xlr_bitpos)
6095 lhs = make_bit_field_ref (loc, ll_inner, lntype, lnbitsize, lnbitpos,
6096 ll_unsignedp || rl_unsignedp);
6097 if (! all_ones_mask_p (ll_mask, lnbitsize))
6098 lhs = build2 (BIT_AND_EXPR, lntype, lhs, ll_mask);
6100 rhs = make_bit_field_ref (loc, lr_inner, rntype, rnbitsize, rnbitpos,
6101 lr_unsignedp || rr_unsignedp);
6102 if (! all_ones_mask_p (lr_mask, rnbitsize))
6103 rhs = build2 (BIT_AND_EXPR, rntype, rhs, lr_mask);
6105 result = build2 (wanted_code, truth_type, lhs, rhs);
6106 goto fold_truthop_exit;
6109 /* There is still another way we can do something: If both pairs of
6110 fields being compared are adjacent, we may be able to make a wider
6111 field containing them both.
6113 Note that we still must mask the lhs/rhs expressions. Furthermore,
6114 the mask must be shifted to account for the shift done by
6115 make_bit_field_ref. */
6116 if ((ll_bitsize + ll_bitpos == rl_bitpos
6117 && lr_bitsize + lr_bitpos == rr_bitpos)
6118 || (ll_bitpos == rl_bitpos + rl_bitsize
6119 && lr_bitpos == rr_bitpos + rr_bitsize))
6123 lhs = make_bit_field_ref (loc, ll_inner, lntype,
6124 ll_bitsize + rl_bitsize,
6125 MIN (ll_bitpos, rl_bitpos), ll_unsignedp);
6126 rhs = make_bit_field_ref (loc, lr_inner, rntype,
6127 lr_bitsize + rr_bitsize,
6128 MIN (lr_bitpos, rr_bitpos), lr_unsignedp);
6130 ll_mask = const_binop (RSHIFT_EXPR, ll_mask,
6131 size_int (MIN (xll_bitpos, xrl_bitpos)), 0);
6132 lr_mask = const_binop (RSHIFT_EXPR, lr_mask,
6133 size_int (MIN (xlr_bitpos, xrr_bitpos)), 0);
6135 /* Convert to the smaller type before masking out unwanted bits. */
6137 if (lntype != rntype)
6139 if (lnbitsize > rnbitsize)
6141 lhs = fold_convert_loc (loc, rntype, lhs);
6142 ll_mask = fold_convert_loc (loc, rntype, ll_mask);
6145 else if (lnbitsize < rnbitsize)
6147 rhs = fold_convert_loc (loc, lntype, rhs);
6148 lr_mask = fold_convert_loc (loc, lntype, lr_mask);
6153 if (! all_ones_mask_p (ll_mask, ll_bitsize + rl_bitsize))
6154 lhs = build2 (BIT_AND_EXPR, type, lhs, ll_mask);
6156 if (! all_ones_mask_p (lr_mask, lr_bitsize + rr_bitsize))
6157 rhs = build2 (BIT_AND_EXPR, type, rhs, lr_mask);
6159 result = build2 (wanted_code, truth_type, lhs, rhs);
6160 goto fold_truthop_exit;
6166 /* Handle the case of comparisons with constants. If there is something in
6167 common between the masks, those bits of the constants must be the same.
6168 If not, the condition is always false. Test for this to avoid generating
6169 incorrect code below. */
6170 result = const_binop (BIT_AND_EXPR, ll_mask, rl_mask, 0);
6171 if (! integer_zerop (result)
6172 && simple_cst_equal (const_binop (BIT_AND_EXPR, result, l_const, 0),
6173 const_binop (BIT_AND_EXPR, result, r_const, 0)) != 1)
6175 if (wanted_code == NE_EXPR)
6177 warning (0, "%<or%> of unmatched not-equal tests is always 1");
6178 return constant_boolean_node (true, truth_type);
6182 warning (0, "%<and%> of mutually exclusive equal-tests is always 0");
6183 return constant_boolean_node (false, truth_type);
6187 /* Construct the expression we will return. First get the component
6188 reference we will make. Unless the mask is all ones the width of
6189 that field, perform the mask operation. Then compare with the
6191 result = make_bit_field_ref (loc, ll_inner, lntype, lnbitsize, lnbitpos,
6192 ll_unsignedp || rl_unsignedp);
6194 ll_mask = const_binop (BIT_IOR_EXPR, ll_mask, rl_mask, 0);
6195 if (! all_ones_mask_p (ll_mask, lnbitsize))
6197 result = build2 (BIT_AND_EXPR, lntype, result, ll_mask);
6198 SET_EXPR_LOCATION (result, loc);
6201 result = build2 (wanted_code, truth_type, result,
6202 const_binop (BIT_IOR_EXPR, l_const, r_const, 0));
6205 SET_EXPR_LOCATION (result, loc);
6209 /* Optimize T, which is a comparison of a MIN_EXPR or MAX_EXPR with a
6213 optimize_minmax_comparison (location_t loc, enum tree_code code, tree type,
6217 enum tree_code op_code;
6220 int consts_equal, consts_lt;
6223 STRIP_SIGN_NOPS (arg0);
6225 op_code = TREE_CODE (arg0);
6226 minmax_const = TREE_OPERAND (arg0, 1);
6227 comp_const = fold_convert_loc (loc, TREE_TYPE (arg0), op1);
6228 consts_equal = tree_int_cst_equal (minmax_const, comp_const);
6229 consts_lt = tree_int_cst_lt (minmax_const, comp_const);
6230 inner = TREE_OPERAND (arg0, 0);
6232 /* If something does not permit us to optimize, return the original tree. */
6233 if ((op_code != MIN_EXPR && op_code != MAX_EXPR)
6234 || TREE_CODE (comp_const) != INTEGER_CST
6235 || TREE_OVERFLOW (comp_const)
6236 || TREE_CODE (minmax_const) != INTEGER_CST
6237 || TREE_OVERFLOW (minmax_const))
6240 /* Now handle all the various comparison codes. We only handle EQ_EXPR
6241 and GT_EXPR, doing the rest with recursive calls using logical
6245 case NE_EXPR: case LT_EXPR: case LE_EXPR:
6248 = optimize_minmax_comparison (loc,
6249 invert_tree_comparison (code, false),
6252 return invert_truthvalue_loc (loc, tem);
6258 fold_build2_loc (loc, TRUTH_ORIF_EXPR, type,
6259 optimize_minmax_comparison
6260 (loc, EQ_EXPR, type, arg0, comp_const),
6261 optimize_minmax_comparison
6262 (loc, GT_EXPR, type, arg0, comp_const));
6265 if (op_code == MAX_EXPR && consts_equal)
6266 /* MAX (X, 0) == 0 -> X <= 0 */
6267 return fold_build2_loc (loc, LE_EXPR, type, inner, comp_const);
6269 else if (op_code == MAX_EXPR && consts_lt)
6270 /* MAX (X, 0) == 5 -> X == 5 */
6271 return fold_build2_loc (loc, EQ_EXPR, type, inner, comp_const);
6273 else if (op_code == MAX_EXPR)
6274 /* MAX (X, 0) == -1 -> false */
6275 return omit_one_operand_loc (loc, type, integer_zero_node, inner);
6277 else if (consts_equal)
6278 /* MIN (X, 0) == 0 -> X >= 0 */
6279 return fold_build2_loc (loc, GE_EXPR, type, inner, comp_const);
6282 /* MIN (X, 0) == 5 -> false */
6283 return omit_one_operand_loc (loc, type, integer_zero_node, inner);
6286 /* MIN (X, 0) == -1 -> X == -1 */
6287 return fold_build2_loc (loc, EQ_EXPR, type, inner, comp_const);
6290 if (op_code == MAX_EXPR && (consts_equal || consts_lt))
6291 /* MAX (X, 0) > 0 -> X > 0
6292 MAX (X, 0) > 5 -> X > 5 */
6293 return fold_build2_loc (loc, GT_EXPR, type, inner, comp_const);
6295 else if (op_code == MAX_EXPR)
6296 /* MAX (X, 0) > -1 -> true */
6297 return omit_one_operand_loc (loc, type, integer_one_node, inner);
6299 else if (op_code == MIN_EXPR && (consts_equal || consts_lt))
6300 /* MIN (X, 0) > 0 -> false
6301 MIN (X, 0) > 5 -> false */
6302 return omit_one_operand_loc (loc, type, integer_zero_node, inner);
6305 /* MIN (X, 0) > -1 -> X > -1 */
6306 return fold_build2_loc (loc, GT_EXPR, type, inner, comp_const);
6313 /* T is an integer expression that is being multiplied, divided, or taken a
6314 modulus (CODE says which and what kind of divide or modulus) by a
6315 constant C. See if we can eliminate that operation by folding it with
6316 other operations already in T. WIDE_TYPE, if non-null, is a type that
6317 should be used for the computation if wider than our type.
6319 For example, if we are dividing (X * 8) + (Y * 16) by 4, we can return
6320 (X * 2) + (Y * 4). We must, however, be assured that either the original
6321 expression would not overflow or that overflow is undefined for the type
6322 in the language in question.
6324 If we return a non-null expression, it is an equivalent form of the
6325 original computation, but need not be in the original type.
6327 We set *STRICT_OVERFLOW_P to true if the return values depends on
6328 signed overflow being undefined. Otherwise we do not change
6329 *STRICT_OVERFLOW_P. */
6332 extract_muldiv (tree t, tree c, enum tree_code code, tree wide_type,
6333 bool *strict_overflow_p)
6335 /* To avoid exponential search depth, refuse to allow recursion past
6336 three levels. Beyond that (1) it's highly unlikely that we'll find
6337 something interesting and (2) we've probably processed it before
6338 when we built the inner expression. */
6347 ret = extract_muldiv_1 (t, c, code, wide_type, strict_overflow_p);
6354 extract_muldiv_1 (tree t, tree c, enum tree_code code, tree wide_type,
6355 bool *strict_overflow_p)
6357 tree type = TREE_TYPE (t);
6358 enum tree_code tcode = TREE_CODE (t);
6359 tree ctype = (wide_type != 0 && (GET_MODE_SIZE (TYPE_MODE (wide_type))
6360 > GET_MODE_SIZE (TYPE_MODE (type)))
6361 ? wide_type : type);
6363 int same_p = tcode == code;
6364 tree op0 = NULL_TREE, op1 = NULL_TREE;
6365 bool sub_strict_overflow_p;
6367 /* Don't deal with constants of zero here; they confuse the code below. */
6368 if (integer_zerop (c))
6371 if (TREE_CODE_CLASS (tcode) == tcc_unary)
6372 op0 = TREE_OPERAND (t, 0);
6374 if (TREE_CODE_CLASS (tcode) == tcc_binary)
6375 op0 = TREE_OPERAND (t, 0), op1 = TREE_OPERAND (t, 1);
6377 /* Note that we need not handle conditional operations here since fold
6378 already handles those cases. So just do arithmetic here. */
6382 /* For a constant, we can always simplify if we are a multiply
6383 or (for divide and modulus) if it is a multiple of our constant. */
6384 if (code == MULT_EXPR
6385 || integer_zerop (const_binop (TRUNC_MOD_EXPR, t, c, 0)))
6386 return const_binop (code, fold_convert (ctype, t),
6387 fold_convert (ctype, c), 0);
6390 CASE_CONVERT: case NON_LVALUE_EXPR:
6391 /* If op0 is an expression ... */
6392 if ((COMPARISON_CLASS_P (op0)
6393 || UNARY_CLASS_P (op0)
6394 || BINARY_CLASS_P (op0)
6395 || VL_EXP_CLASS_P (op0)
6396 || EXPRESSION_CLASS_P (op0))
6397 /* ... and has wrapping overflow, and its type is smaller
6398 than ctype, then we cannot pass through as widening. */
6399 && ((TYPE_OVERFLOW_WRAPS (TREE_TYPE (op0))
6400 && ! (TREE_CODE (TREE_TYPE (op0)) == INTEGER_TYPE
6401 && TYPE_IS_SIZETYPE (TREE_TYPE (op0)))
6402 && (TYPE_PRECISION (ctype)
6403 > TYPE_PRECISION (TREE_TYPE (op0))))
6404 /* ... or this is a truncation (t is narrower than op0),
6405 then we cannot pass through this narrowing. */
6406 || (TYPE_PRECISION (type)
6407 < TYPE_PRECISION (TREE_TYPE (op0)))
6408 /* ... or signedness changes for division or modulus,
6409 then we cannot pass through this conversion. */
6410 || (code != MULT_EXPR
6411 && (TYPE_UNSIGNED (ctype)
6412 != TYPE_UNSIGNED (TREE_TYPE (op0))))
6413 /* ... or has undefined overflow while the converted to
6414 type has not, we cannot do the operation in the inner type
6415 as that would introduce undefined overflow. */
6416 || (TYPE_OVERFLOW_UNDEFINED (TREE_TYPE (op0))
6417 && !TYPE_OVERFLOW_UNDEFINED (type))))
6420 /* Pass the constant down and see if we can make a simplification. If
6421 we can, replace this expression with the inner simplification for
6422 possible later conversion to our or some other type. */
6423 if ((t2 = fold_convert (TREE_TYPE (op0), c)) != 0
6424 && TREE_CODE (t2) == INTEGER_CST
6425 && !TREE_OVERFLOW (t2)
6426 && (0 != (t1 = extract_muldiv (op0, t2, code,
6428 ? ctype : NULL_TREE,
6429 strict_overflow_p))))
6434 /* If widening the type changes it from signed to unsigned, then we
6435 must avoid building ABS_EXPR itself as unsigned. */
6436 if (TYPE_UNSIGNED (ctype) && !TYPE_UNSIGNED (type))
6438 tree cstype = (*signed_type_for) (ctype);
6439 if ((t1 = extract_muldiv (op0, c, code, cstype, strict_overflow_p))
6442 t1 = fold_build1 (tcode, cstype, fold_convert (cstype, t1));
6443 return fold_convert (ctype, t1);
6447 /* If the constant is negative, we cannot simplify this. */
6448 if (tree_int_cst_sgn (c) == -1)
6452 if ((t1 = extract_muldiv (op0, c, code, wide_type, strict_overflow_p))
6454 return fold_build1 (tcode, ctype, fold_convert (ctype, t1));
6457 case MIN_EXPR: case MAX_EXPR:
6458 /* If widening the type changes the signedness, then we can't perform
6459 this optimization as that changes the result. */
6460 if (TYPE_UNSIGNED (ctype) != TYPE_UNSIGNED (type))
6463 /* MIN (a, b) / 5 -> MIN (a / 5, b / 5) */
6464 sub_strict_overflow_p = false;
6465 if ((t1 = extract_muldiv (op0, c, code, wide_type,
6466 &sub_strict_overflow_p)) != 0
6467 && (t2 = extract_muldiv (op1, c, code, wide_type,
6468 &sub_strict_overflow_p)) != 0)
6470 if (tree_int_cst_sgn (c) < 0)
6471 tcode = (tcode == MIN_EXPR ? MAX_EXPR : MIN_EXPR);
6472 if (sub_strict_overflow_p)
6473 *strict_overflow_p = true;
6474 return fold_build2 (tcode, ctype, fold_convert (ctype, t1),
6475 fold_convert (ctype, t2));
6479 case LSHIFT_EXPR: case RSHIFT_EXPR:
6480 /* If the second operand is constant, this is a multiplication
6481 or floor division, by a power of two, so we can treat it that
6482 way unless the multiplier or divisor overflows. Signed
6483 left-shift overflow is implementation-defined rather than
6484 undefined in C90, so do not convert signed left shift into
6486 if (TREE_CODE (op1) == INTEGER_CST
6487 && (tcode == RSHIFT_EXPR || TYPE_UNSIGNED (TREE_TYPE (op0)))
6488 /* const_binop may not detect overflow correctly,
6489 so check for it explicitly here. */
6490 && TYPE_PRECISION (TREE_TYPE (size_one_node)) > TREE_INT_CST_LOW (op1)
6491 && TREE_INT_CST_HIGH (op1) == 0
6492 && 0 != (t1 = fold_convert (ctype,
6493 const_binop (LSHIFT_EXPR,
6496 && !TREE_OVERFLOW (t1))
6497 return extract_muldiv (build2 (tcode == LSHIFT_EXPR
6498 ? MULT_EXPR : FLOOR_DIV_EXPR,
6500 fold_convert (ctype, op0),
6502 c, code, wide_type, strict_overflow_p);
6505 case PLUS_EXPR: case MINUS_EXPR:
6506 /* See if we can eliminate the operation on both sides. If we can, we
6507 can return a new PLUS or MINUS. If we can't, the only remaining
6508 cases where we can do anything are if the second operand is a
6510 sub_strict_overflow_p = false;
6511 t1 = extract_muldiv (op0, c, code, wide_type, &sub_strict_overflow_p);
6512 t2 = extract_muldiv (op1, c, code, wide_type, &sub_strict_overflow_p);
6513 if (t1 != 0 && t2 != 0
6514 && (code == MULT_EXPR
6515 /* If not multiplication, we can only do this if both operands
6516 are divisible by c. */
6517 || (multiple_of_p (ctype, op0, c)
6518 && multiple_of_p (ctype, op1, c))))
6520 if (sub_strict_overflow_p)
6521 *strict_overflow_p = true;
6522 return fold_build2 (tcode, ctype, fold_convert (ctype, t1),
6523 fold_convert (ctype, t2));
6526 /* If this was a subtraction, negate OP1 and set it to be an addition.
6527 This simplifies the logic below. */
6528 if (tcode == MINUS_EXPR)
6530 tcode = PLUS_EXPR, op1 = negate_expr (op1);
6531 /* If OP1 was not easily negatable, the constant may be OP0. */
6532 if (TREE_CODE (op0) == INTEGER_CST)
6543 if (TREE_CODE (op1) != INTEGER_CST)
6546 /* If either OP1 or C are negative, this optimization is not safe for
6547 some of the division and remainder types while for others we need
6548 to change the code. */
6549 if (tree_int_cst_sgn (op1) < 0 || tree_int_cst_sgn (c) < 0)
6551 if (code == CEIL_DIV_EXPR)
6552 code = FLOOR_DIV_EXPR;
6553 else if (code == FLOOR_DIV_EXPR)
6554 code = CEIL_DIV_EXPR;
6555 else if (code != MULT_EXPR
6556 && code != CEIL_MOD_EXPR && code != FLOOR_MOD_EXPR)
6560 /* If it's a multiply or a division/modulus operation of a multiple
6561 of our constant, do the operation and verify it doesn't overflow. */
6562 if (code == MULT_EXPR
6563 || integer_zerop (const_binop (TRUNC_MOD_EXPR, op1, c, 0)))
6565 op1 = const_binop (code, fold_convert (ctype, op1),
6566 fold_convert (ctype, c), 0);
6567 /* We allow the constant to overflow with wrapping semantics. */
6569 || (TREE_OVERFLOW (op1) && !TYPE_OVERFLOW_WRAPS (ctype)))
6575 /* If we have an unsigned type is not a sizetype, we cannot widen
6576 the operation since it will change the result if the original
6577 computation overflowed. */
6578 if (TYPE_UNSIGNED (ctype)
6579 && ! (TREE_CODE (ctype) == INTEGER_TYPE && TYPE_IS_SIZETYPE (ctype))
6583 /* If we were able to eliminate our operation from the first side,
6584 apply our operation to the second side and reform the PLUS. */
6585 if (t1 != 0 && (TREE_CODE (t1) != code || code == MULT_EXPR))
6586 return fold_build2 (tcode, ctype, fold_convert (ctype, t1), op1);
6588 /* The last case is if we are a multiply. In that case, we can
6589 apply the distributive law to commute the multiply and addition
6590 if the multiplication of the constants doesn't overflow. */
6591 if (code == MULT_EXPR)
6592 return fold_build2 (tcode, ctype,
6593 fold_build2 (code, ctype,
6594 fold_convert (ctype, op0),
6595 fold_convert (ctype, c)),
6601 /* We have a special case here if we are doing something like
6602 (C * 8) % 4 since we know that's zero. */
6603 if ((code == TRUNC_MOD_EXPR || code == CEIL_MOD_EXPR
6604 || code == FLOOR_MOD_EXPR || code == ROUND_MOD_EXPR)
6605 /* If the multiplication can overflow we cannot optimize this.
6606 ??? Until we can properly mark individual operations as
6607 not overflowing we need to treat sizetype special here as
6608 stor-layout relies on this opimization to make
6609 DECL_FIELD_BIT_OFFSET always a constant. */
6610 && (TYPE_OVERFLOW_UNDEFINED (TREE_TYPE (t))
6611 || (TREE_CODE (TREE_TYPE (t)) == INTEGER_TYPE
6612 && TYPE_IS_SIZETYPE (TREE_TYPE (t))))
6613 && TREE_CODE (TREE_OPERAND (t, 1)) == INTEGER_CST
6614 && integer_zerop (const_binop (TRUNC_MOD_EXPR, op1, c, 0)))
6616 *strict_overflow_p = true;
6617 return omit_one_operand (type, integer_zero_node, op0);
6620 /* ... fall through ... */
6622 case TRUNC_DIV_EXPR: case CEIL_DIV_EXPR: case FLOOR_DIV_EXPR:
6623 case ROUND_DIV_EXPR: case EXACT_DIV_EXPR:
6624 /* If we can extract our operation from the LHS, do so and return a
6625 new operation. Likewise for the RHS from a MULT_EXPR. Otherwise,
6626 do something only if the second operand is a constant. */
6628 && (t1 = extract_muldiv (op0, c, code, wide_type,
6629 strict_overflow_p)) != 0)
6630 return fold_build2 (tcode, ctype, fold_convert (ctype, t1),
6631 fold_convert (ctype, op1));
6632 else if (tcode == MULT_EXPR && code == MULT_EXPR
6633 && (t1 = extract_muldiv (op1, c, code, wide_type,
6634 strict_overflow_p)) != 0)
6635 return fold_build2 (tcode, ctype, fold_convert (ctype, op0),
6636 fold_convert (ctype, t1));
6637 else if (TREE_CODE (op1) != INTEGER_CST)
6640 /* If these are the same operation types, we can associate them
6641 assuming no overflow. */
6643 && 0 != (t1 = int_const_binop (MULT_EXPR,
6644 fold_convert (ctype, op1),
6645 fold_convert (ctype, c), 1))
6646 && 0 != (t1 = force_fit_type_double (ctype, TREE_INT_CST_LOW (t1),
6647 TREE_INT_CST_HIGH (t1),
6648 (TYPE_UNSIGNED (ctype)
6649 && tcode != MULT_EXPR) ? -1 : 1,
6650 TREE_OVERFLOW (t1)))
6651 && !TREE_OVERFLOW (t1))
6652 return fold_build2 (tcode, ctype, fold_convert (ctype, op0), t1);
6654 /* If these operations "cancel" each other, we have the main
6655 optimizations of this pass, which occur when either constant is a
6656 multiple of the other, in which case we replace this with either an
6657 operation or CODE or TCODE.
6659 If we have an unsigned type that is not a sizetype, we cannot do
6660 this since it will change the result if the original computation
6662 if ((TYPE_OVERFLOW_UNDEFINED (ctype)
6663 || (TREE_CODE (ctype) == INTEGER_TYPE && TYPE_IS_SIZETYPE (ctype)))
6664 && ((code == MULT_EXPR && tcode == EXACT_DIV_EXPR)
6665 || (tcode == MULT_EXPR
6666 && code != TRUNC_MOD_EXPR && code != CEIL_MOD_EXPR
6667 && code != FLOOR_MOD_EXPR && code != ROUND_MOD_EXPR
6668 && code != MULT_EXPR)))
6670 if (integer_zerop (const_binop (TRUNC_MOD_EXPR, op1, c, 0)))
6672 if (TYPE_OVERFLOW_UNDEFINED (ctype))
6673 *strict_overflow_p = true;
6674 return fold_build2 (tcode, ctype, fold_convert (ctype, op0),
6675 fold_convert (ctype,
6676 const_binop (TRUNC_DIV_EXPR,
6679 else if (integer_zerop (const_binop (TRUNC_MOD_EXPR, c, op1, 0)))
6681 if (TYPE_OVERFLOW_UNDEFINED (ctype))
6682 *strict_overflow_p = true;
6683 return fold_build2 (code, ctype, fold_convert (ctype, op0),
6684 fold_convert (ctype,
6685 const_binop (TRUNC_DIV_EXPR,
6698 /* Return a node which has the indicated constant VALUE (either 0 or
6699 1), and is of the indicated TYPE. */
6702 constant_boolean_node (int value, tree type)
6704 if (type == integer_type_node)
6705 return value ? integer_one_node : integer_zero_node;
6706 else if (type == boolean_type_node)
6707 return value ? boolean_true_node : boolean_false_node;
6709 return build_int_cst (type, value);
6713 /* Transform `a + (b ? x : y)' into `b ? (a + x) : (a + y)'.
6714 Transform, `a + (x < y)' into `(x < y) ? (a + 1) : (a + 0)'. Here
6715 CODE corresponds to the `+', COND to the `(b ? x : y)' or `(x < y)'
6716 expression, and ARG to `a'. If COND_FIRST_P is nonzero, then the
6717 COND is the first argument to CODE; otherwise (as in the example
6718 given here), it is the second argument. TYPE is the type of the
6719 original expression. Return NULL_TREE if no simplification is
6723 fold_binary_op_with_conditional_arg (location_t loc,
6724 enum tree_code code,
6725 tree type, tree op0, tree op1,
6726 tree cond, tree arg, int cond_first_p)
6728 tree cond_type = cond_first_p ? TREE_TYPE (op0) : TREE_TYPE (op1);
6729 tree arg_type = cond_first_p ? TREE_TYPE (op1) : TREE_TYPE (op0);
6730 tree test, true_value, false_value;
6731 tree lhs = NULL_TREE;
6732 tree rhs = NULL_TREE;
6734 /* This transformation is only worthwhile if we don't have to wrap
6735 arg in a SAVE_EXPR, and the operation can be simplified on at least
6736 one of the branches once its pushed inside the COND_EXPR. */
6737 if (!TREE_CONSTANT (arg))
6740 if (TREE_CODE (cond) == COND_EXPR)
6742 test = TREE_OPERAND (cond, 0);
6743 true_value = TREE_OPERAND (cond, 1);
6744 false_value = TREE_OPERAND (cond, 2);
6745 /* If this operand throws an expression, then it does not make
6746 sense to try to perform a logical or arithmetic operation
6748 if (VOID_TYPE_P (TREE_TYPE (true_value)))
6750 if (VOID_TYPE_P (TREE_TYPE (false_value)))
6755 tree testtype = TREE_TYPE (cond);
6757 true_value = constant_boolean_node (true, testtype);
6758 false_value = constant_boolean_node (false, testtype);
6761 arg = fold_convert_loc (loc, arg_type, arg);
6764 true_value = fold_convert_loc (loc, cond_type, true_value);
6766 lhs = fold_build2_loc (loc, code, type, true_value, arg);
6768 lhs = fold_build2_loc (loc, code, type, arg, true_value);
6772 false_value = fold_convert_loc (loc, cond_type, false_value);
6774 rhs = fold_build2_loc (loc, code, type, false_value, arg);
6776 rhs = fold_build2_loc (loc, code, type, arg, false_value);
6779 test = fold_build3_loc (loc, COND_EXPR, type, test, lhs, rhs);
6780 return fold_convert_loc (loc, type, test);
6784 /* Subroutine of fold() that checks for the addition of +/- 0.0.
6786 If !NEGATE, return true if ADDEND is +/-0.0 and, for all X of type
6787 TYPE, X + ADDEND is the same as X. If NEGATE, return true if X -
6788 ADDEND is the same as X.
6790 X + 0 and X - 0 both give X when X is NaN, infinite, or nonzero
6791 and finite. The problematic cases are when X is zero, and its mode
6792 has signed zeros. In the case of rounding towards -infinity,
6793 X - 0 is not the same as X because 0 - 0 is -0. In other rounding
6794 modes, X + 0 is not the same as X because -0 + 0 is 0. */
6797 fold_real_zero_addition_p (const_tree type, const_tree addend, int negate)
6799 if (!real_zerop (addend))
6802 /* Don't allow the fold with -fsignaling-nans. */
6803 if (HONOR_SNANS (TYPE_MODE (type)))
6806 /* Allow the fold if zeros aren't signed, or their sign isn't important. */
6807 if (!HONOR_SIGNED_ZEROS (TYPE_MODE (type)))
6810 /* Treat x + -0 as x - 0 and x - -0 as x + 0. */
6811 if (TREE_CODE (addend) == REAL_CST
6812 && REAL_VALUE_MINUS_ZERO (TREE_REAL_CST (addend)))
6815 /* The mode has signed zeros, and we have to honor their sign.
6816 In this situation, there is only one case we can return true for.
6817 X - 0 is the same as X unless rounding towards -infinity is
6819 return negate && !HONOR_SIGN_DEPENDENT_ROUNDING (TYPE_MODE (type));
6822 /* Subroutine of fold() that checks comparisons of built-in math
6823 functions against real constants.
6825 FCODE is the DECL_FUNCTION_CODE of the built-in, CODE is the comparison
6826 operator: EQ_EXPR, NE_EXPR, GT_EXPR, LT_EXPR, GE_EXPR or LE_EXPR. TYPE
6827 is the type of the result and ARG0 and ARG1 are the operands of the
6828 comparison. ARG1 must be a TREE_REAL_CST.
6830 The function returns the constant folded tree if a simplification
6831 can be made, and NULL_TREE otherwise. */
6834 fold_mathfn_compare (location_t loc,
6835 enum built_in_function fcode, enum tree_code code,
6836 tree type, tree arg0, tree arg1)
6840 if (BUILTIN_SQRT_P (fcode))
6842 tree arg = CALL_EXPR_ARG (arg0, 0);
6843 enum machine_mode mode = TYPE_MODE (TREE_TYPE (arg0));
6845 c = TREE_REAL_CST (arg1);
6846 if (REAL_VALUE_NEGATIVE (c))
6848 /* sqrt(x) < y is always false, if y is negative. */
6849 if (code == EQ_EXPR || code == LT_EXPR || code == LE_EXPR)
6850 return omit_one_operand_loc (loc, type, integer_zero_node, arg);
6852 /* sqrt(x) > y is always true, if y is negative and we
6853 don't care about NaNs, i.e. negative values of x. */
6854 if (code == NE_EXPR || !HONOR_NANS (mode))
6855 return omit_one_operand_loc (loc, type, integer_one_node, arg);
6857 /* sqrt(x) > y is the same as x >= 0, if y is negative. */
6858 return fold_build2_loc (loc, GE_EXPR, type, arg,
6859 build_real (TREE_TYPE (arg), dconst0));
6861 else if (code == GT_EXPR || code == GE_EXPR)
6865 REAL_ARITHMETIC (c2, MULT_EXPR, c, c);
6866 real_convert (&c2, mode, &c2);
6868 if (REAL_VALUE_ISINF (c2))
6870 /* sqrt(x) > y is x == +Inf, when y is very large. */
6871 if (HONOR_INFINITIES (mode))
6872 return fold_build2_loc (loc, EQ_EXPR, type, arg,
6873 build_real (TREE_TYPE (arg), c2));
6875 /* sqrt(x) > y is always false, when y is very large
6876 and we don't care about infinities. */
6877 return omit_one_operand_loc (loc, type, integer_zero_node, arg);
6880 /* sqrt(x) > c is the same as x > c*c. */
6881 return fold_build2_loc (loc, code, type, arg,
6882 build_real (TREE_TYPE (arg), c2));
6884 else if (code == LT_EXPR || code == LE_EXPR)
6888 REAL_ARITHMETIC (c2, MULT_EXPR, c, c);
6889 real_convert (&c2, mode, &c2);
6891 if (REAL_VALUE_ISINF (c2))
6893 /* sqrt(x) < y is always true, when y is a very large
6894 value and we don't care about NaNs or Infinities. */
6895 if (! HONOR_NANS (mode) && ! HONOR_INFINITIES (mode))
6896 return omit_one_operand_loc (loc, type, integer_one_node, arg);
6898 /* sqrt(x) < y is x != +Inf when y is very large and we
6899 don't care about NaNs. */
6900 if (! HONOR_NANS (mode))
6901 return fold_build2_loc (loc, NE_EXPR, type, arg,
6902 build_real (TREE_TYPE (arg), c2));
6904 /* sqrt(x) < y is x >= 0 when y is very large and we
6905 don't care about Infinities. */
6906 if (! HONOR_INFINITIES (mode))
6907 return fold_build2_loc (loc, GE_EXPR, type, arg,
6908 build_real (TREE_TYPE (arg), dconst0));
6910 /* sqrt(x) < y is x >= 0 && x != +Inf, when y is large. */
6911 if (lang_hooks.decls.global_bindings_p () != 0
6912 || CONTAINS_PLACEHOLDER_P (arg))
6915 arg = save_expr (arg);
6916 return fold_build2_loc (loc, TRUTH_ANDIF_EXPR, type,
6917 fold_build2_loc (loc, GE_EXPR, type, arg,
6918 build_real (TREE_TYPE (arg),
6920 fold_build2_loc (loc, NE_EXPR, type, arg,
6921 build_real (TREE_TYPE (arg),
6925 /* sqrt(x) < c is the same as x < c*c, if we ignore NaNs. */
6926 if (! HONOR_NANS (mode))
6927 return fold_build2_loc (loc, code, type, arg,
6928 build_real (TREE_TYPE (arg), c2));
6930 /* sqrt(x) < c is the same as x >= 0 && x < c*c. */
6931 if (lang_hooks.decls.global_bindings_p () == 0
6932 && ! CONTAINS_PLACEHOLDER_P (arg))
6934 arg = save_expr (arg);
6935 return fold_build2_loc (loc, TRUTH_ANDIF_EXPR, type,
6936 fold_build2_loc (loc, GE_EXPR, type, arg,
6937 build_real (TREE_TYPE (arg),
6939 fold_build2_loc (loc, code, type, arg,
6940 build_real (TREE_TYPE (arg),
6949 /* Subroutine of fold() that optimizes comparisons against Infinities,
6950 either +Inf or -Inf.
6952 CODE is the comparison operator: EQ_EXPR, NE_EXPR, GT_EXPR, LT_EXPR,
6953 GE_EXPR or LE_EXPR. TYPE is the type of the result and ARG0 and ARG1
6954 are the operands of the comparison. ARG1 must be a TREE_REAL_CST.
6956 The function returns the constant folded tree if a simplification
6957 can be made, and NULL_TREE otherwise. */
6960 fold_inf_compare (location_t loc, enum tree_code code, tree type,
6961 tree arg0, tree arg1)
6963 enum machine_mode mode;
6964 REAL_VALUE_TYPE max;
6968 mode = TYPE_MODE (TREE_TYPE (arg0));
6970 /* For negative infinity swap the sense of the comparison. */
6971 neg = REAL_VALUE_NEGATIVE (TREE_REAL_CST (arg1));
6973 code = swap_tree_comparison (code);
6978 /* x > +Inf is always false, if with ignore sNANs. */
6979 if (HONOR_SNANS (mode))
6981 return omit_one_operand_loc (loc, type, integer_zero_node, arg0);
6984 /* x <= +Inf is always true, if we don't case about NaNs. */
6985 if (! HONOR_NANS (mode))
6986 return omit_one_operand_loc (loc, type, integer_one_node, arg0);
6988 /* x <= +Inf is the same as x == x, i.e. isfinite(x). */
6989 if (lang_hooks.decls.global_bindings_p () == 0
6990 && ! CONTAINS_PLACEHOLDER_P (arg0))
6992 arg0 = save_expr (arg0);
6993 return fold_build2_loc (loc, EQ_EXPR, type, arg0, arg0);
6999 /* x == +Inf and x >= +Inf are always equal to x > DBL_MAX. */
7000 real_maxval (&max, neg, mode);
7001 return fold_build2_loc (loc, neg ? LT_EXPR : GT_EXPR, type,
7002 arg0, build_real (TREE_TYPE (arg0), max));
7005 /* x < +Inf is always equal to x <= DBL_MAX. */
7006 real_maxval (&max, neg, mode);
7007 return fold_build2_loc (loc, neg ? GE_EXPR : LE_EXPR, type,
7008 arg0, build_real (TREE_TYPE (arg0), max));
7011 /* x != +Inf is always equal to !(x > DBL_MAX). */
7012 real_maxval (&max, neg, mode);
7013 if (! HONOR_NANS (mode))
7014 return fold_build2_loc (loc, neg ? GE_EXPR : LE_EXPR, type,
7015 arg0, build_real (TREE_TYPE (arg0), max));
7017 temp = fold_build2_loc (loc, neg ? LT_EXPR : GT_EXPR, type,
7018 arg0, build_real (TREE_TYPE (arg0), max));
7019 return fold_build1_loc (loc, TRUTH_NOT_EXPR, type, temp);
7028 /* Subroutine of fold() that optimizes comparisons of a division by
7029 a nonzero integer constant against an integer constant, i.e.
7032 CODE is the comparison operator: EQ_EXPR, NE_EXPR, GT_EXPR, LT_EXPR,
7033 GE_EXPR or LE_EXPR. TYPE is the type of the result and ARG0 and ARG1
7034 are the operands of the comparison. ARG1 must be a TREE_REAL_CST.
7036 The function returns the constant folded tree if a simplification
7037 can be made, and NULL_TREE otherwise. */
7040 fold_div_compare (location_t loc,
7041 enum tree_code code, tree type, tree arg0, tree arg1)
7043 tree prod, tmp, hi, lo;
7044 tree arg00 = TREE_OPERAND (arg0, 0);
7045 tree arg01 = TREE_OPERAND (arg0, 1);
7046 unsigned HOST_WIDE_INT lpart;
7047 HOST_WIDE_INT hpart;
7048 bool unsigned_p = TYPE_UNSIGNED (TREE_TYPE (arg0));
7052 /* We have to do this the hard way to detect unsigned overflow.
7053 prod = int_const_binop (MULT_EXPR, arg01, arg1, 0); */
7054 overflow = mul_double_with_sign (TREE_INT_CST_LOW (arg01),
7055 TREE_INT_CST_HIGH (arg01),
7056 TREE_INT_CST_LOW (arg1),
7057 TREE_INT_CST_HIGH (arg1),
7058 &lpart, &hpart, unsigned_p);
7059 prod = force_fit_type_double (TREE_TYPE (arg00), lpart, hpart,
7061 neg_overflow = false;
7065 tmp = int_const_binop (MINUS_EXPR, arg01,
7066 build_int_cst (TREE_TYPE (arg01), 1), 0);
7069 /* Likewise hi = int_const_binop (PLUS_EXPR, prod, tmp, 0). */
7070 overflow = add_double_with_sign (TREE_INT_CST_LOW (prod),
7071 TREE_INT_CST_HIGH (prod),
7072 TREE_INT_CST_LOW (tmp),
7073 TREE_INT_CST_HIGH (tmp),
7074 &lpart, &hpart, unsigned_p);
7075 hi = force_fit_type_double (TREE_TYPE (arg00), lpart, hpart,
7076 -1, overflow | TREE_OVERFLOW (prod));
7078 else if (tree_int_cst_sgn (arg01) >= 0)
7080 tmp = int_const_binop (MINUS_EXPR, arg01,
7081 build_int_cst (TREE_TYPE (arg01), 1), 0);
7082 switch (tree_int_cst_sgn (arg1))
7085 neg_overflow = true;
7086 lo = int_const_binop (MINUS_EXPR, prod, tmp, 0);
7091 lo = fold_negate_const (tmp, TREE_TYPE (arg0));
7096 hi = int_const_binop (PLUS_EXPR, prod, tmp, 0);
7106 /* A negative divisor reverses the relational operators. */
7107 code = swap_tree_comparison (code);
7109 tmp = int_const_binop (PLUS_EXPR, arg01,
7110 build_int_cst (TREE_TYPE (arg01), 1), 0);
7111 switch (tree_int_cst_sgn (arg1))
7114 hi = int_const_binop (MINUS_EXPR, prod, tmp, 0);
7119 hi = fold_negate_const (tmp, TREE_TYPE (arg0));
7124 neg_overflow = true;
7125 lo = int_const_binop (PLUS_EXPR, prod, tmp, 0);
7137 if (TREE_OVERFLOW (lo) && TREE_OVERFLOW (hi))
7138 return omit_one_operand_loc (loc, type, integer_zero_node, arg00);
7139 if (TREE_OVERFLOW (hi))
7140 return fold_build2_loc (loc, GE_EXPR, type, arg00, lo);
7141 if (TREE_OVERFLOW (lo))
7142 return fold_build2_loc (loc, LE_EXPR, type, arg00, hi);
7143 return build_range_check (loc, type, arg00, 1, lo, hi);
7146 if (TREE_OVERFLOW (lo) && TREE_OVERFLOW (hi))
7147 return omit_one_operand_loc (loc, type, integer_one_node, arg00);
7148 if (TREE_OVERFLOW (hi))
7149 return fold_build2_loc (loc, LT_EXPR, type, arg00, lo);
7150 if (TREE_OVERFLOW (lo))
7151 return fold_build2_loc (loc, GT_EXPR, type, arg00, hi);
7152 return build_range_check (loc, type, arg00, 0, lo, hi);
7155 if (TREE_OVERFLOW (lo))
7157 tmp = neg_overflow ? integer_zero_node : integer_one_node;
7158 return omit_one_operand_loc (loc, type, tmp, arg00);
7160 return fold_build2_loc (loc, LT_EXPR, type, arg00, lo);
7163 if (TREE_OVERFLOW (hi))
7165 tmp = neg_overflow ? integer_zero_node : integer_one_node;
7166 return omit_one_operand_loc (loc, type, tmp, arg00);
7168 return fold_build2_loc (loc, LE_EXPR, type, arg00, hi);
7171 if (TREE_OVERFLOW (hi))
7173 tmp = neg_overflow ? integer_one_node : integer_zero_node;
7174 return omit_one_operand_loc (loc, type, tmp, arg00);
7176 return fold_build2_loc (loc, GT_EXPR, type, arg00, hi);
7179 if (TREE_OVERFLOW (lo))
7181 tmp = neg_overflow ? integer_one_node : integer_zero_node;
7182 return omit_one_operand_loc (loc, type, tmp, arg00);
7184 return fold_build2_loc (loc, GE_EXPR, type, arg00, lo);
7194 /* If CODE with arguments ARG0 and ARG1 represents a single bit
7195 equality/inequality test, then return a simplified form of the test
7196 using a sign testing. Otherwise return NULL. TYPE is the desired
7200 fold_single_bit_test_into_sign_test (location_t loc,
7201 enum tree_code code, tree arg0, tree arg1,
7204 /* If this is testing a single bit, we can optimize the test. */
7205 if ((code == NE_EXPR || code == EQ_EXPR)
7206 && TREE_CODE (arg0) == BIT_AND_EXPR && integer_zerop (arg1)
7207 && integer_pow2p (TREE_OPERAND (arg0, 1)))
7209 /* If we have (A & C) != 0 where C is the sign bit of A, convert
7210 this into A < 0. Similarly for (A & C) == 0 into A >= 0. */
7211 tree arg00 = sign_bit_p (TREE_OPERAND (arg0, 0), TREE_OPERAND (arg0, 1));
7213 if (arg00 != NULL_TREE
7214 /* This is only a win if casting to a signed type is cheap,
7215 i.e. when arg00's type is not a partial mode. */
7216 && TYPE_PRECISION (TREE_TYPE (arg00))
7217 == GET_MODE_BITSIZE (TYPE_MODE (TREE_TYPE (arg00))))
7219 tree stype = signed_type_for (TREE_TYPE (arg00));
7220 return fold_build2_loc (loc, code == EQ_EXPR ? GE_EXPR : LT_EXPR,
7222 fold_convert_loc (loc, stype, arg00),
7223 build_int_cst (stype, 0));
7230 /* If CODE with arguments ARG0 and ARG1 represents a single bit
7231 equality/inequality test, then return a simplified form of
7232 the test using shifts and logical operations. Otherwise return
7233 NULL. TYPE is the desired result type. */
7236 fold_single_bit_test (location_t loc, enum tree_code code,
7237 tree arg0, tree arg1, tree result_type)
7239 /* If this is testing a single bit, we can optimize the test. */
7240 if ((code == NE_EXPR || code == EQ_EXPR)
7241 && TREE_CODE (arg0) == BIT_AND_EXPR && integer_zerop (arg1)
7242 && integer_pow2p (TREE_OPERAND (arg0, 1)))
7244 tree inner = TREE_OPERAND (arg0, 0);
7245 tree type = TREE_TYPE (arg0);
7246 int bitnum = tree_log2 (TREE_OPERAND (arg0, 1));
7247 enum machine_mode operand_mode = TYPE_MODE (type);
7249 tree signed_type, unsigned_type, intermediate_type;
7252 /* First, see if we can fold the single bit test into a sign-bit
7254 tem = fold_single_bit_test_into_sign_test (loc, code, arg0, arg1,
7259 /* Otherwise we have (A & C) != 0 where C is a single bit,
7260 convert that into ((A >> C2) & 1). Where C2 = log2(C).
7261 Similarly for (A & C) == 0. */
7263 /* If INNER is a right shift of a constant and it plus BITNUM does
7264 not overflow, adjust BITNUM and INNER. */
7265 if (TREE_CODE (inner) == RSHIFT_EXPR
7266 && TREE_CODE (TREE_OPERAND (inner, 1)) == INTEGER_CST
7267 && TREE_INT_CST_HIGH (TREE_OPERAND (inner, 1)) == 0
7268 && bitnum < TYPE_PRECISION (type)
7269 && 0 > compare_tree_int (TREE_OPERAND (inner, 1),
7270 bitnum - TYPE_PRECISION (type)))
7272 bitnum += TREE_INT_CST_LOW (TREE_OPERAND (inner, 1));
7273 inner = TREE_OPERAND (inner, 0);
7276 /* If we are going to be able to omit the AND below, we must do our
7277 operations as unsigned. If we must use the AND, we have a choice.
7278 Normally unsigned is faster, but for some machines signed is. */
7279 #ifdef LOAD_EXTEND_OP
7280 ops_unsigned = (LOAD_EXTEND_OP (operand_mode) == SIGN_EXTEND
7281 && !flag_syntax_only) ? 0 : 1;
7286 signed_type = lang_hooks.types.type_for_mode (operand_mode, 0);
7287 unsigned_type = lang_hooks.types.type_for_mode (operand_mode, 1);
7288 intermediate_type = ops_unsigned ? unsigned_type : signed_type;
7289 inner = fold_convert_loc (loc, intermediate_type, inner);
7292 inner = build2 (RSHIFT_EXPR, intermediate_type,
7293 inner, size_int (bitnum));
7295 one = build_int_cst (intermediate_type, 1);
7297 if (code == EQ_EXPR)
7298 inner = fold_build2_loc (loc, BIT_XOR_EXPR, intermediate_type, inner, one);
7300 /* Put the AND last so it can combine with more things. */
7301 inner = build2 (BIT_AND_EXPR, intermediate_type, inner, one);
7303 /* Make sure to return the proper type. */
7304 inner = fold_convert_loc (loc, result_type, inner);
7311 /* Check whether we are allowed to reorder operands arg0 and arg1,
7312 such that the evaluation of arg1 occurs before arg0. */
7315 reorder_operands_p (const_tree arg0, const_tree arg1)
7317 if (! flag_evaluation_order)
7319 if (TREE_CONSTANT (arg0) || TREE_CONSTANT (arg1))
7321 return ! TREE_SIDE_EFFECTS (arg0)
7322 && ! TREE_SIDE_EFFECTS (arg1);
7325 /* Test whether it is preferable two swap two operands, ARG0 and
7326 ARG1, for example because ARG0 is an integer constant and ARG1
7327 isn't. If REORDER is true, only recommend swapping if we can
7328 evaluate the operands in reverse order. */
7331 tree_swap_operands_p (const_tree arg0, const_tree arg1, bool reorder)
7333 STRIP_SIGN_NOPS (arg0);
7334 STRIP_SIGN_NOPS (arg1);
7336 if (TREE_CODE (arg1) == INTEGER_CST)
7338 if (TREE_CODE (arg0) == INTEGER_CST)
7341 if (TREE_CODE (arg1) == REAL_CST)
7343 if (TREE_CODE (arg0) == REAL_CST)
7346 if (TREE_CODE (arg1) == FIXED_CST)
7348 if (TREE_CODE (arg0) == FIXED_CST)
7351 if (TREE_CODE (arg1) == COMPLEX_CST)
7353 if (TREE_CODE (arg0) == COMPLEX_CST)
7356 if (TREE_CONSTANT (arg1))
7358 if (TREE_CONSTANT (arg0))
7361 if (optimize_function_for_size_p (cfun))
7364 if (reorder && flag_evaluation_order
7365 && (TREE_SIDE_EFFECTS (arg0) || TREE_SIDE_EFFECTS (arg1)))
7368 /* It is preferable to swap two SSA_NAME to ensure a canonical form
7369 for commutative and comparison operators. Ensuring a canonical
7370 form allows the optimizers to find additional redundancies without
7371 having to explicitly check for both orderings. */
7372 if (TREE_CODE (arg0) == SSA_NAME
7373 && TREE_CODE (arg1) == SSA_NAME
7374 && SSA_NAME_VERSION (arg0) > SSA_NAME_VERSION (arg1))
7377 /* Put SSA_NAMEs last. */
7378 if (TREE_CODE (arg1) == SSA_NAME)
7380 if (TREE_CODE (arg0) == SSA_NAME)
7383 /* Put variables last. */
7392 /* Fold comparison ARG0 CODE ARG1 (with result in TYPE), where
7393 ARG0 is extended to a wider type. */
7396 fold_widened_comparison (location_t loc, enum tree_code code,
7397 tree type, tree arg0, tree arg1)
7399 tree arg0_unw = get_unwidened (arg0, NULL_TREE);
7401 tree shorter_type, outer_type;
7405 if (arg0_unw == arg0)
7407 shorter_type = TREE_TYPE (arg0_unw);
7409 #ifdef HAVE_canonicalize_funcptr_for_compare
7410 /* Disable this optimization if we're casting a function pointer
7411 type on targets that require function pointer canonicalization. */
7412 if (HAVE_canonicalize_funcptr_for_compare
7413 && TREE_CODE (shorter_type) == POINTER_TYPE
7414 && TREE_CODE (TREE_TYPE (shorter_type)) == FUNCTION_TYPE)
7418 if (TYPE_PRECISION (TREE_TYPE (arg0)) <= TYPE_PRECISION (shorter_type))
7421 arg1_unw = get_unwidened (arg1, NULL_TREE);
7423 /* If possible, express the comparison in the shorter mode. */
7424 if ((code == EQ_EXPR || code == NE_EXPR
7425 || TYPE_UNSIGNED (TREE_TYPE (arg0)) == TYPE_UNSIGNED (shorter_type))
7426 && (TREE_TYPE (arg1_unw) == shorter_type
7427 || ((TYPE_PRECISION (shorter_type)
7428 >= TYPE_PRECISION (TREE_TYPE (arg1_unw)))
7429 && (TYPE_UNSIGNED (shorter_type)
7430 == TYPE_UNSIGNED (TREE_TYPE (arg1_unw))))
7431 || (TREE_CODE (arg1_unw) == INTEGER_CST
7432 && (TREE_CODE (shorter_type) == INTEGER_TYPE
7433 || TREE_CODE (shorter_type) == BOOLEAN_TYPE)
7434 && int_fits_type_p (arg1_unw, shorter_type))))
7435 return fold_build2_loc (loc, code, type, arg0_unw,
7436 fold_convert_loc (loc, shorter_type, arg1_unw));
7438 if (TREE_CODE (arg1_unw) != INTEGER_CST
7439 || TREE_CODE (shorter_type) != INTEGER_TYPE
7440 || !int_fits_type_p (arg1_unw, shorter_type))
7443 /* If we are comparing with the integer that does not fit into the range
7444 of the shorter type, the result is known. */
7445 outer_type = TREE_TYPE (arg1_unw);
7446 min = lower_bound_in_type (outer_type, shorter_type);
7447 max = upper_bound_in_type (outer_type, shorter_type);
7449 above = integer_nonzerop (fold_relational_const (LT_EXPR, type,
7451 below = integer_nonzerop (fold_relational_const (LT_EXPR, type,
7458 return omit_one_operand_loc (loc, type, integer_zero_node, arg0);
7463 return omit_one_operand_loc (loc, type, integer_one_node, arg0);
7469 return omit_one_operand_loc (loc, type, integer_one_node, arg0);
7471 return omit_one_operand_loc (loc, type, integer_zero_node, arg0);
7476 return omit_one_operand_loc (loc, type, integer_zero_node, arg0);
7478 return omit_one_operand_loc (loc, type, integer_one_node, arg0);
7487 /* Fold comparison ARG0 CODE ARG1 (with result in TYPE), where for
7488 ARG0 just the signedness is changed. */
7491 fold_sign_changed_comparison (location_t loc, enum tree_code code, tree type,
7492 tree arg0, tree arg1)
7495 tree inner_type, outer_type;
7497 if (!CONVERT_EXPR_P (arg0))
7500 outer_type = TREE_TYPE (arg0);
7501 arg0_inner = TREE_OPERAND (arg0, 0);
7502 inner_type = TREE_TYPE (arg0_inner);
7504 #ifdef HAVE_canonicalize_funcptr_for_compare
7505 /* Disable this optimization if we're casting a function pointer
7506 type on targets that require function pointer canonicalization. */
7507 if (HAVE_canonicalize_funcptr_for_compare
7508 && TREE_CODE (inner_type) == POINTER_TYPE
7509 && TREE_CODE (TREE_TYPE (inner_type)) == FUNCTION_TYPE)
7513 if (TYPE_PRECISION (inner_type) != TYPE_PRECISION (outer_type))
7516 if (TREE_CODE (arg1) != INTEGER_CST
7517 && !(CONVERT_EXPR_P (arg1)
7518 && TREE_TYPE (TREE_OPERAND (arg1, 0)) == inner_type))
7521 if ((TYPE_UNSIGNED (inner_type) != TYPE_UNSIGNED (outer_type)
7522 || POINTER_TYPE_P (inner_type) != POINTER_TYPE_P (outer_type))
7527 if (TREE_CODE (arg1) == INTEGER_CST)
7528 arg1 = force_fit_type_double (inner_type, TREE_INT_CST_LOW (arg1),
7529 TREE_INT_CST_HIGH (arg1), 0,
7530 TREE_OVERFLOW (arg1));
7532 arg1 = fold_convert_loc (loc, inner_type, arg1);
7534 return fold_build2_loc (loc, code, type, arg0_inner, arg1);
7537 /* Tries to replace &a[idx] p+ s * delta with &a[idx + delta], if s is
7538 step of the array. Reconstructs s and delta in the case of s *
7539 delta being an integer constant (and thus already folded). ADDR is
7540 the address. MULT is the multiplicative expression. If the
7541 function succeeds, the new address expression is returned.
7542 Otherwise NULL_TREE is returned. LOC is the location of the
7543 resulting expression. */
7546 try_move_mult_to_index (location_t loc, tree addr, tree op1)
7548 tree s, delta, step;
7549 tree ref = TREE_OPERAND (addr, 0), pref;
7554 /* Strip the nops that might be added when converting op1 to sizetype. */
7557 /* Canonicalize op1 into a possibly non-constant delta
7558 and an INTEGER_CST s. */
7559 if (TREE_CODE (op1) == MULT_EXPR)
7561 tree arg0 = TREE_OPERAND (op1, 0), arg1 = TREE_OPERAND (op1, 1);
7566 if (TREE_CODE (arg0) == INTEGER_CST)
7571 else if (TREE_CODE (arg1) == INTEGER_CST)
7579 else if (TREE_CODE (op1) == INTEGER_CST)
7586 /* Simulate we are delta * 1. */
7588 s = integer_one_node;
7591 for (;; ref = TREE_OPERAND (ref, 0))
7593 if (TREE_CODE (ref) == ARRAY_REF)
7597 /* Remember if this was a multi-dimensional array. */
7598 if (TREE_CODE (TREE_OPERAND (ref, 0)) == ARRAY_REF)
7601 domain = TYPE_DOMAIN (TREE_TYPE (TREE_OPERAND (ref, 0)));
7604 itype = TREE_TYPE (domain);
7606 step = array_ref_element_size (ref);
7607 if (TREE_CODE (step) != INTEGER_CST)
7612 if (! tree_int_cst_equal (step, s))
7617 /* Try if delta is a multiple of step. */
7618 tree tmp = div_if_zero_remainder (EXACT_DIV_EXPR, op1, step);
7624 /* Only fold here if we can verify we do not overflow one
7625 dimension of a multi-dimensional array. */
7630 if (TREE_CODE (TREE_OPERAND (ref, 1)) != INTEGER_CST
7631 || !TYPE_MAX_VALUE (domain)
7632 || TREE_CODE (TYPE_MAX_VALUE (domain)) != INTEGER_CST)
7635 tmp = fold_binary_loc (loc, PLUS_EXPR, itype,
7636 fold_convert_loc (loc, itype,
7637 TREE_OPERAND (ref, 1)),
7638 fold_convert_loc (loc, itype, delta));
7640 || TREE_CODE (tmp) != INTEGER_CST
7641 || tree_int_cst_lt (TYPE_MAX_VALUE (domain), tmp))
7650 if (!handled_component_p (ref))
7654 /* We found the suitable array reference. So copy everything up to it,
7655 and replace the index. */
7657 pref = TREE_OPERAND (addr, 0);
7658 ret = copy_node (pref);
7659 SET_EXPR_LOCATION (ret, loc);
7664 pref = TREE_OPERAND (pref, 0);
7665 TREE_OPERAND (pos, 0) = copy_node (pref);
7666 pos = TREE_OPERAND (pos, 0);
7669 TREE_OPERAND (pos, 1) = fold_build2_loc (loc, PLUS_EXPR, itype,
7670 fold_convert_loc (loc, itype,
7671 TREE_OPERAND (pos, 1)),
7672 fold_convert_loc (loc, itype, delta));
7674 return fold_build1_loc (loc, ADDR_EXPR, TREE_TYPE (addr), ret);
7678 /* Fold A < X && A + 1 > Y to A < X && A >= Y. Normally A + 1 > Y
7679 means A >= Y && A != MAX, but in this case we know that
7680 A < X <= MAX. INEQ is A + 1 > Y, BOUND is A < X. */
7683 fold_to_nonsharp_ineq_using_bound (location_t loc, tree ineq, tree bound)
7685 tree a, typea, type = TREE_TYPE (ineq), a1, diff, y;
7687 if (TREE_CODE (bound) == LT_EXPR)
7688 a = TREE_OPERAND (bound, 0);
7689 else if (TREE_CODE (bound) == GT_EXPR)
7690 a = TREE_OPERAND (bound, 1);
7694 typea = TREE_TYPE (a);
7695 if (!INTEGRAL_TYPE_P (typea)
7696 && !POINTER_TYPE_P (typea))
7699 if (TREE_CODE (ineq) == LT_EXPR)
7701 a1 = TREE_OPERAND (ineq, 1);
7702 y = TREE_OPERAND (ineq, 0);
7704 else if (TREE_CODE (ineq) == GT_EXPR)
7706 a1 = TREE_OPERAND (ineq, 0);
7707 y = TREE_OPERAND (ineq, 1);
7712 if (TREE_TYPE (a1) != typea)
7715 if (POINTER_TYPE_P (typea))
7717 /* Convert the pointer types into integer before taking the difference. */
7718 tree ta = fold_convert_loc (loc, ssizetype, a);
7719 tree ta1 = fold_convert_loc (loc, ssizetype, a1);
7720 diff = fold_binary_loc (loc, MINUS_EXPR, ssizetype, ta1, ta);
7723 diff = fold_binary_loc (loc, MINUS_EXPR, typea, a1, a);
7725 if (!diff || !integer_onep (diff))
7728 return fold_build2_loc (loc, GE_EXPR, type, a, y);
7731 /* Fold a sum or difference of at least one multiplication.
7732 Returns the folded tree or NULL if no simplification could be made. */
7735 fold_plusminus_mult_expr (location_t loc, enum tree_code code, tree type,
7736 tree arg0, tree arg1)
7738 tree arg00, arg01, arg10, arg11;
7739 tree alt0 = NULL_TREE, alt1 = NULL_TREE, same;
7741 /* (A * C) +- (B * C) -> (A+-B) * C.
7742 (A * C) +- A -> A * (C+-1).
7743 We are most concerned about the case where C is a constant,
7744 but other combinations show up during loop reduction. Since
7745 it is not difficult, try all four possibilities. */
7747 if (TREE_CODE (arg0) == MULT_EXPR)
7749 arg00 = TREE_OPERAND (arg0, 0);
7750 arg01 = TREE_OPERAND (arg0, 1);
7752 else if (TREE_CODE (arg0) == INTEGER_CST)
7754 arg00 = build_one_cst (type);
7759 /* We cannot generate constant 1 for fract. */
7760 if (ALL_FRACT_MODE_P (TYPE_MODE (type)))
7763 arg01 = build_one_cst (type);
7765 if (TREE_CODE (arg1) == MULT_EXPR)
7767 arg10 = TREE_OPERAND (arg1, 0);
7768 arg11 = TREE_OPERAND (arg1, 1);
7770 else if (TREE_CODE (arg1) == INTEGER_CST)
7772 arg10 = build_one_cst (type);
7773 /* As we canonicalize A - 2 to A + -2 get rid of that sign for
7774 the purpose of this canonicalization. */
7775 if (TREE_INT_CST_HIGH (arg1) == -1
7776 && negate_expr_p (arg1)
7777 && code == PLUS_EXPR)
7779 arg11 = negate_expr (arg1);
7787 /* We cannot generate constant 1 for fract. */
7788 if (ALL_FRACT_MODE_P (TYPE_MODE (type)))
7791 arg11 = build_one_cst (type);
7795 if (operand_equal_p (arg01, arg11, 0))
7796 same = arg01, alt0 = arg00, alt1 = arg10;
7797 else if (operand_equal_p (arg00, arg10, 0))
7798 same = arg00, alt0 = arg01, alt1 = arg11;
7799 else if (operand_equal_p (arg00, arg11, 0))
7800 same = arg00, alt0 = arg01, alt1 = arg10;
7801 else if (operand_equal_p (arg01, arg10, 0))
7802 same = arg01, alt0 = arg00, alt1 = arg11;
7804 /* No identical multiplicands; see if we can find a common
7805 power-of-two factor in non-power-of-two multiplies. This
7806 can help in multi-dimensional array access. */
7807 else if (host_integerp (arg01, 0)
7808 && host_integerp (arg11, 0))
7810 HOST_WIDE_INT int01, int11, tmp;
7813 int01 = TREE_INT_CST_LOW (arg01);
7814 int11 = TREE_INT_CST_LOW (arg11);
7816 /* Move min of absolute values to int11. */
7817 if ((int01 >= 0 ? int01 : -int01)
7818 < (int11 >= 0 ? int11 : -int11))
7820 tmp = int01, int01 = int11, int11 = tmp;
7821 alt0 = arg00, arg00 = arg10, arg10 = alt0;
7828 if (exact_log2 (abs (int11)) > 0 && int01 % int11 == 0
7829 /* The remainder should not be a constant, otherwise we
7830 end up folding i * 4 + 2 to (i * 2 + 1) * 2 which has
7831 increased the number of multiplications necessary. */
7832 && TREE_CODE (arg10) != INTEGER_CST)
7834 alt0 = fold_build2_loc (loc, MULT_EXPR, TREE_TYPE (arg00), arg00,
7835 build_int_cst (TREE_TYPE (arg00),
7840 maybe_same = alt0, alt0 = alt1, alt1 = maybe_same;
7845 return fold_build2_loc (loc, MULT_EXPR, type,
7846 fold_build2_loc (loc, code, type,
7847 fold_convert_loc (loc, type, alt0),
7848 fold_convert_loc (loc, type, alt1)),
7849 fold_convert_loc (loc, type, same));
7854 /* Subroutine of native_encode_expr. Encode the INTEGER_CST
7855 specified by EXPR into the buffer PTR of length LEN bytes.
7856 Return the number of bytes placed in the buffer, or zero
7860 native_encode_int (const_tree expr, unsigned char *ptr, int len)
7862 tree type = TREE_TYPE (expr);
7863 int total_bytes = GET_MODE_SIZE (TYPE_MODE (type));
7864 int byte, offset, word, words;
7865 unsigned char value;
7867 if (total_bytes > len)
7869 words = total_bytes / UNITS_PER_WORD;
7871 for (byte = 0; byte < total_bytes; byte++)
7873 int bitpos = byte * BITS_PER_UNIT;
7874 if (bitpos < HOST_BITS_PER_WIDE_INT)
7875 value = (unsigned char) (TREE_INT_CST_LOW (expr) >> bitpos);
7877 value = (unsigned char) (TREE_INT_CST_HIGH (expr)
7878 >> (bitpos - HOST_BITS_PER_WIDE_INT));
7880 if (total_bytes > UNITS_PER_WORD)
7882 word = byte / UNITS_PER_WORD;
7883 if (WORDS_BIG_ENDIAN)
7884 word = (words - 1) - word;
7885 offset = word * UNITS_PER_WORD;
7886 if (BYTES_BIG_ENDIAN)
7887 offset += (UNITS_PER_WORD - 1) - (byte % UNITS_PER_WORD);
7889 offset += byte % UNITS_PER_WORD;
7892 offset = BYTES_BIG_ENDIAN ? (total_bytes - 1) - byte : byte;
7893 ptr[offset] = value;
7899 /* Subroutine of native_encode_expr. Encode the REAL_CST
7900 specified by EXPR into the buffer PTR of length LEN bytes.
7901 Return the number of bytes placed in the buffer, or zero
7905 native_encode_real (const_tree expr, unsigned char *ptr, int len)
7907 tree type = TREE_TYPE (expr);
7908 int total_bytes = GET_MODE_SIZE (TYPE_MODE (type));
7909 int byte, offset, word, words, bitpos;
7910 unsigned char value;
7912 /* There are always 32 bits in each long, no matter the size of
7913 the hosts long. We handle floating point representations with
7917 if (total_bytes > len)
7919 words = (32 / BITS_PER_UNIT) / UNITS_PER_WORD;
7921 real_to_target (tmp, TREE_REAL_CST_PTR (expr), TYPE_MODE (type));
7923 for (bitpos = 0; bitpos < total_bytes * BITS_PER_UNIT;
7924 bitpos += BITS_PER_UNIT)
7926 byte = (bitpos / BITS_PER_UNIT) & 3;
7927 value = (unsigned char) (tmp[bitpos / 32] >> (bitpos & 31));
7929 if (UNITS_PER_WORD < 4)
7931 word = byte / UNITS_PER_WORD;
7932 if (WORDS_BIG_ENDIAN)
7933 word = (words - 1) - word;
7934 offset = word * UNITS_PER_WORD;
7935 if (BYTES_BIG_ENDIAN)
7936 offset += (UNITS_PER_WORD - 1) - (byte % UNITS_PER_WORD);
7938 offset += byte % UNITS_PER_WORD;
7941 offset = BYTES_BIG_ENDIAN ? 3 - byte : byte;
7942 ptr[offset + ((bitpos / BITS_PER_UNIT) & ~3)] = value;
7947 /* Subroutine of native_encode_expr. Encode the COMPLEX_CST
7948 specified by EXPR into the buffer PTR of length LEN bytes.
7949 Return the number of bytes placed in the buffer, or zero
7953 native_encode_complex (const_tree expr, unsigned char *ptr, int len)
7958 part = TREE_REALPART (expr);
7959 rsize = native_encode_expr (part, ptr, len);
7962 part = TREE_IMAGPART (expr);
7963 isize = native_encode_expr (part, ptr+rsize, len-rsize);
7966 return rsize + isize;
7970 /* Subroutine of native_encode_expr. Encode the VECTOR_CST
7971 specified by EXPR into the buffer PTR of length LEN bytes.
7972 Return the number of bytes placed in the buffer, or zero
7976 native_encode_vector (const_tree expr, unsigned char *ptr, int len)
7978 int i, size, offset, count;
7979 tree itype, elem, elements;
7982 elements = TREE_VECTOR_CST_ELTS (expr);
7983 count = TYPE_VECTOR_SUBPARTS (TREE_TYPE (expr));
7984 itype = TREE_TYPE (TREE_TYPE (expr));
7985 size = GET_MODE_SIZE (TYPE_MODE (itype));
7986 for (i = 0; i < count; i++)
7990 elem = TREE_VALUE (elements);
7991 elements = TREE_CHAIN (elements);
7998 if (native_encode_expr (elem, ptr+offset, len-offset) != size)
8003 if (offset + size > len)
8005 memset (ptr+offset, 0, size);
8013 /* Subroutine of native_encode_expr. Encode the STRING_CST
8014 specified by EXPR into the buffer PTR of length LEN bytes.
8015 Return the number of bytes placed in the buffer, or zero
8019 native_encode_string (const_tree expr, unsigned char *ptr, int len)
8021 tree type = TREE_TYPE (expr);
8022 HOST_WIDE_INT total_bytes;
8024 if (TREE_CODE (type) != ARRAY_TYPE
8025 || TREE_CODE (TREE_TYPE (type)) != INTEGER_TYPE
8026 || GET_MODE_BITSIZE (TYPE_MODE (TREE_TYPE (type))) != BITS_PER_UNIT
8027 || !host_integerp (TYPE_SIZE_UNIT (type), 0))
8029 total_bytes = tree_low_cst (TYPE_SIZE_UNIT (type), 0);
8030 if (total_bytes > len)
8032 if (TREE_STRING_LENGTH (expr) < total_bytes)
8034 memcpy (ptr, TREE_STRING_POINTER (expr), TREE_STRING_LENGTH (expr));
8035 memset (ptr + TREE_STRING_LENGTH (expr), 0,
8036 total_bytes - TREE_STRING_LENGTH (expr));
8039 memcpy (ptr, TREE_STRING_POINTER (expr), total_bytes);
8044 /* Subroutine of fold_view_convert_expr. Encode the INTEGER_CST,
8045 REAL_CST, COMPLEX_CST or VECTOR_CST specified by EXPR into the
8046 buffer PTR of length LEN bytes. Return the number of bytes
8047 placed in the buffer, or zero upon failure. */
8050 native_encode_expr (const_tree expr, unsigned char *ptr, int len)
8052 switch (TREE_CODE (expr))
8055 return native_encode_int (expr, ptr, len);
8058 return native_encode_real (expr, ptr, len);
8061 return native_encode_complex (expr, ptr, len);
8064 return native_encode_vector (expr, ptr, len);
8067 return native_encode_string (expr, ptr, len);
8075 /* Subroutine of native_interpret_expr. Interpret the contents of
8076 the buffer PTR of length LEN as an INTEGER_CST of type TYPE.
8077 If the buffer cannot be interpreted, return NULL_TREE. */
8080 native_interpret_int (tree type, const unsigned char *ptr, int len)
8082 int total_bytes = GET_MODE_SIZE (TYPE_MODE (type));
8083 int byte, offset, word, words;
8084 unsigned char value;
8085 unsigned int HOST_WIDE_INT lo = 0;
8086 HOST_WIDE_INT hi = 0;
8088 if (total_bytes > len)
8090 if (total_bytes * BITS_PER_UNIT > 2 * HOST_BITS_PER_WIDE_INT)
8092 words = total_bytes / UNITS_PER_WORD;
8094 for (byte = 0; byte < total_bytes; byte++)
8096 int bitpos = byte * BITS_PER_UNIT;
8097 if (total_bytes > UNITS_PER_WORD)
8099 word = byte / UNITS_PER_WORD;
8100 if (WORDS_BIG_ENDIAN)
8101 word = (words - 1) - word;
8102 offset = word * UNITS_PER_WORD;
8103 if (BYTES_BIG_ENDIAN)
8104 offset += (UNITS_PER_WORD - 1) - (byte % UNITS_PER_WORD);
8106 offset += byte % UNITS_PER_WORD;
8109 offset = BYTES_BIG_ENDIAN ? (total_bytes - 1) - byte : byte;
8110 value = ptr[offset];
8112 if (bitpos < HOST_BITS_PER_WIDE_INT)
8113 lo |= (unsigned HOST_WIDE_INT) value << bitpos;
8115 hi |= (unsigned HOST_WIDE_INT) value
8116 << (bitpos - HOST_BITS_PER_WIDE_INT);
8119 return build_int_cst_wide_type (type, lo, hi);
8123 /* Subroutine of native_interpret_expr. Interpret the contents of
8124 the buffer PTR of length LEN as a REAL_CST of type TYPE.
8125 If the buffer cannot be interpreted, return NULL_TREE. */
8128 native_interpret_real (tree type, const unsigned char *ptr, int len)
8130 enum machine_mode mode = TYPE_MODE (type);
8131 int total_bytes = GET_MODE_SIZE (mode);
8132 int byte, offset, word, words, bitpos;
8133 unsigned char value;
8134 /* There are always 32 bits in each long, no matter the size of
8135 the hosts long. We handle floating point representations with
8140 total_bytes = GET_MODE_SIZE (TYPE_MODE (type));
8141 if (total_bytes > len || total_bytes > 24)
8143 words = (32 / BITS_PER_UNIT) / UNITS_PER_WORD;
8145 memset (tmp, 0, sizeof (tmp));
8146 for (bitpos = 0; bitpos < total_bytes * BITS_PER_UNIT;
8147 bitpos += BITS_PER_UNIT)
8149 byte = (bitpos / BITS_PER_UNIT) & 3;
8150 if (UNITS_PER_WORD < 4)
8152 word = byte / UNITS_PER_WORD;
8153 if (WORDS_BIG_ENDIAN)
8154 word = (words - 1) - word;
8155 offset = word * UNITS_PER_WORD;
8156 if (BYTES_BIG_ENDIAN)
8157 offset += (UNITS_PER_WORD - 1) - (byte % UNITS_PER_WORD);
8159 offset += byte % UNITS_PER_WORD;
8162 offset = BYTES_BIG_ENDIAN ? 3 - byte : byte;
8163 value = ptr[offset + ((bitpos / BITS_PER_UNIT) & ~3)];
8165 tmp[bitpos / 32] |= (unsigned long)value << (bitpos & 31);
8168 real_from_target (&r, tmp, mode);
8169 return build_real (type, r);
8173 /* Subroutine of native_interpret_expr. Interpret the contents of
8174 the buffer PTR of length LEN as a COMPLEX_CST of type TYPE.
8175 If the buffer cannot be interpreted, return NULL_TREE. */
8178 native_interpret_complex (tree type, const unsigned char *ptr, int len)
8180 tree etype, rpart, ipart;
8183 etype = TREE_TYPE (type);
8184 size = GET_MODE_SIZE (TYPE_MODE (etype));
8187 rpart = native_interpret_expr (etype, ptr, size);
8190 ipart = native_interpret_expr (etype, ptr+size, size);
8193 return build_complex (type, rpart, ipart);
8197 /* Subroutine of native_interpret_expr. Interpret the contents of
8198 the buffer PTR of length LEN as a VECTOR_CST of type TYPE.
8199 If the buffer cannot be interpreted, return NULL_TREE. */
8202 native_interpret_vector (tree type, const unsigned char *ptr, int len)
8204 tree etype, elem, elements;
8207 etype = TREE_TYPE (type);
8208 size = GET_MODE_SIZE (TYPE_MODE (etype));
8209 count = TYPE_VECTOR_SUBPARTS (type);
8210 if (size * count > len)
8213 elements = NULL_TREE;
8214 for (i = count - 1; i >= 0; i--)
8216 elem = native_interpret_expr (etype, ptr+(i*size), size);
8219 elements = tree_cons (NULL_TREE, elem, elements);
8221 return build_vector (type, elements);
8225 /* Subroutine of fold_view_convert_expr. Interpret the contents of
8226 the buffer PTR of length LEN as a constant of type TYPE. For
8227 INTEGRAL_TYPE_P we return an INTEGER_CST, for SCALAR_FLOAT_TYPE_P
8228 we return a REAL_CST, etc... If the buffer cannot be interpreted,
8229 return NULL_TREE. */
8232 native_interpret_expr (tree type, const unsigned char *ptr, int len)
8234 switch (TREE_CODE (type))
8239 return native_interpret_int (type, ptr, len);
8242 return native_interpret_real (type, ptr, len);
8245 return native_interpret_complex (type, ptr, len);
8248 return native_interpret_vector (type, ptr, len);
8256 /* Fold a VIEW_CONVERT_EXPR of a constant expression EXPR to type
8257 TYPE at compile-time. If we're unable to perform the conversion
8258 return NULL_TREE. */
8261 fold_view_convert_expr (tree type, tree expr)
8263 /* We support up to 512-bit values (for V8DFmode). */
8264 unsigned char buffer[64];
8267 /* Check that the host and target are sane. */
8268 if (CHAR_BIT != 8 || BITS_PER_UNIT != 8)
8271 len = native_encode_expr (expr, buffer, sizeof (buffer));
8275 return native_interpret_expr (type, buffer, len);
8278 /* Build an expression for the address of T. Folds away INDIRECT_REF
8279 to avoid confusing the gimplify process. */
8282 build_fold_addr_expr_with_type_loc (location_t loc, tree t, tree ptrtype)
8284 /* The size of the object is not relevant when talking about its address. */
8285 if (TREE_CODE (t) == WITH_SIZE_EXPR)
8286 t = TREE_OPERAND (t, 0);
8288 /* Note: doesn't apply to ALIGN_INDIRECT_REF */
8289 if (TREE_CODE (t) == INDIRECT_REF
8290 || TREE_CODE (t) == MISALIGNED_INDIRECT_REF)
8292 t = TREE_OPERAND (t, 0);
8294 if (TREE_TYPE (t) != ptrtype)
8296 t = build1 (NOP_EXPR, ptrtype, t);
8297 SET_EXPR_LOCATION (t, loc);
8300 else if (TREE_CODE (t) == VIEW_CONVERT_EXPR)
8302 t = build_fold_addr_expr_loc (loc, TREE_OPERAND (t, 0));
8304 if (TREE_TYPE (t) != ptrtype)
8305 t = fold_convert_loc (loc, ptrtype, t);
8309 t = build1 (ADDR_EXPR, ptrtype, t);
8310 SET_EXPR_LOCATION (t, loc);
8316 /* Build an expression for the address of T. */
8319 build_fold_addr_expr_loc (location_t loc, tree t)
8321 tree ptrtype = build_pointer_type (TREE_TYPE (t));
8323 return build_fold_addr_expr_with_type_loc (loc, t, ptrtype);
8326 /* Fold a unary expression of code CODE and type TYPE with operand
8327 OP0. Return the folded expression if folding is successful.
8328 Otherwise, return NULL_TREE. */
8331 fold_unary_loc (location_t loc, enum tree_code code, tree type, tree op0)
8335 enum tree_code_class kind = TREE_CODE_CLASS (code);
8337 gcc_assert (IS_EXPR_CODE_CLASS (kind)
8338 && TREE_CODE_LENGTH (code) == 1);
8343 if (CONVERT_EXPR_CODE_P (code)
8344 || code == FLOAT_EXPR || code == ABS_EXPR)
8346 /* Don't use STRIP_NOPS, because signedness of argument type
8348 STRIP_SIGN_NOPS (arg0);
8352 /* Strip any conversions that don't change the mode. This
8353 is safe for every expression, except for a comparison
8354 expression because its signedness is derived from its
8357 Note that this is done as an internal manipulation within
8358 the constant folder, in order to find the simplest
8359 representation of the arguments so that their form can be
8360 studied. In any cases, the appropriate type conversions
8361 should be put back in the tree that will get out of the
8367 if (TREE_CODE_CLASS (code) == tcc_unary)
8369 if (TREE_CODE (arg0) == COMPOUND_EXPR)
8370 return build2 (COMPOUND_EXPR, type, TREE_OPERAND (arg0, 0),
8371 fold_build1_loc (loc, code, type,
8372 fold_convert_loc (loc, TREE_TYPE (op0),
8373 TREE_OPERAND (arg0, 1))));
8374 else if (TREE_CODE (arg0) == COND_EXPR)
8376 tree arg01 = TREE_OPERAND (arg0, 1);
8377 tree arg02 = TREE_OPERAND (arg0, 2);
8378 if (! VOID_TYPE_P (TREE_TYPE (arg01)))
8379 arg01 = fold_build1_loc (loc, code, type,
8380 fold_convert_loc (loc,
8381 TREE_TYPE (op0), arg01));
8382 if (! VOID_TYPE_P (TREE_TYPE (arg02)))
8383 arg02 = fold_build1_loc (loc, code, type,
8384 fold_convert_loc (loc,
8385 TREE_TYPE (op0), arg02));
8386 tem = fold_build3_loc (loc, COND_EXPR, type, TREE_OPERAND (arg0, 0),
8389 /* If this was a conversion, and all we did was to move into
8390 inside the COND_EXPR, bring it back out. But leave it if
8391 it is a conversion from integer to integer and the
8392 result precision is no wider than a word since such a
8393 conversion is cheap and may be optimized away by combine,
8394 while it couldn't if it were outside the COND_EXPR. Then return
8395 so we don't get into an infinite recursion loop taking the
8396 conversion out and then back in. */
8398 if ((CONVERT_EXPR_CODE_P (code)
8399 || code == NON_LVALUE_EXPR)
8400 && TREE_CODE (tem) == COND_EXPR
8401 && TREE_CODE (TREE_OPERAND (tem, 1)) == code
8402 && TREE_CODE (TREE_OPERAND (tem, 2)) == code
8403 && ! VOID_TYPE_P (TREE_OPERAND (tem, 1))
8404 && ! VOID_TYPE_P (TREE_OPERAND (tem, 2))
8405 && (TREE_TYPE (TREE_OPERAND (TREE_OPERAND (tem, 1), 0))
8406 == TREE_TYPE (TREE_OPERAND (TREE_OPERAND (tem, 2), 0)))
8407 && (! (INTEGRAL_TYPE_P (TREE_TYPE (tem))
8409 (TREE_TYPE (TREE_OPERAND (TREE_OPERAND (tem, 1), 0))))
8410 && TYPE_PRECISION (TREE_TYPE (tem)) <= BITS_PER_WORD)
8411 || flag_syntax_only))
8413 tem = build1 (code, type,
8415 TREE_TYPE (TREE_OPERAND
8416 (TREE_OPERAND (tem, 1), 0)),
8417 TREE_OPERAND (tem, 0),
8418 TREE_OPERAND (TREE_OPERAND (tem, 1), 0),
8419 TREE_OPERAND (TREE_OPERAND (tem, 2), 0)));
8420 SET_EXPR_LOCATION (tem, loc);
8424 else if (COMPARISON_CLASS_P (arg0))
8426 if (TREE_CODE (type) == BOOLEAN_TYPE)
8428 arg0 = copy_node (arg0);
8429 TREE_TYPE (arg0) = type;
8432 else if (TREE_CODE (type) != INTEGER_TYPE)
8433 return fold_build3_loc (loc, COND_EXPR, type, arg0,
8434 fold_build1_loc (loc, code, type,
8436 fold_build1_loc (loc, code, type,
8437 integer_zero_node));
8444 /* Re-association barriers around constants and other re-association
8445 barriers can be removed. */
8446 if (CONSTANT_CLASS_P (op0)
8447 || TREE_CODE (op0) == PAREN_EXPR)
8448 return fold_convert_loc (loc, type, op0);
8453 case FIX_TRUNC_EXPR:
8454 if (TREE_TYPE (op0) == type)
8457 /* If we have (type) (a CMP b) and type is an integral type, return
8458 new expression involving the new type. */
8459 if (COMPARISON_CLASS_P (op0) && INTEGRAL_TYPE_P (type))
8460 return fold_build2_loc (loc, TREE_CODE (op0), type, TREE_OPERAND (op0, 0),
8461 TREE_OPERAND (op0, 1));
8463 /* Handle cases of two conversions in a row. */
8464 if (CONVERT_EXPR_P (op0))
8466 tree inside_type = TREE_TYPE (TREE_OPERAND (op0, 0));
8467 tree inter_type = TREE_TYPE (op0);
8468 int inside_int = INTEGRAL_TYPE_P (inside_type);
8469 int inside_ptr = POINTER_TYPE_P (inside_type);
8470 int inside_float = FLOAT_TYPE_P (inside_type);
8471 int inside_vec = TREE_CODE (inside_type) == VECTOR_TYPE;
8472 unsigned int inside_prec = TYPE_PRECISION (inside_type);
8473 int inside_unsignedp = TYPE_UNSIGNED (inside_type);
8474 int inter_int = INTEGRAL_TYPE_P (inter_type);
8475 int inter_ptr = POINTER_TYPE_P (inter_type);
8476 int inter_float = FLOAT_TYPE_P (inter_type);
8477 int inter_vec = TREE_CODE (inter_type) == VECTOR_TYPE;
8478 unsigned int inter_prec = TYPE_PRECISION (inter_type);
8479 int inter_unsignedp = TYPE_UNSIGNED (inter_type);
8480 int final_int = INTEGRAL_TYPE_P (type);
8481 int final_ptr = POINTER_TYPE_P (type);
8482 int final_float = FLOAT_TYPE_P (type);
8483 int final_vec = TREE_CODE (type) == VECTOR_TYPE;
8484 unsigned int final_prec = TYPE_PRECISION (type);
8485 int final_unsignedp = TYPE_UNSIGNED (type);
8487 /* In addition to the cases of two conversions in a row
8488 handled below, if we are converting something to its own
8489 type via an object of identical or wider precision, neither
8490 conversion is needed. */
8491 if (TYPE_MAIN_VARIANT (inside_type) == TYPE_MAIN_VARIANT (type)
8492 && (((inter_int || inter_ptr) && final_int)
8493 || (inter_float && final_float))
8494 && inter_prec >= final_prec)
8495 return fold_build1_loc (loc, code, type, TREE_OPERAND (op0, 0));
8497 /* Likewise, if the intermediate and initial types are either both
8498 float or both integer, we don't need the middle conversion if the
8499 former is wider than the latter and doesn't change the signedness
8500 (for integers). Avoid this if the final type is a pointer since
8501 then we sometimes need the middle conversion. Likewise if the
8502 final type has a precision not equal to the size of its mode. */
8503 if (((inter_int && inside_int)
8504 || (inter_float && inside_float)
8505 || (inter_vec && inside_vec))
8506 && inter_prec >= inside_prec
8507 && (inter_float || inter_vec
8508 || inter_unsignedp == inside_unsignedp)
8509 && ! (final_prec != GET_MODE_BITSIZE (TYPE_MODE (type))
8510 && TYPE_MODE (type) == TYPE_MODE (inter_type))
8512 && (! final_vec || inter_prec == inside_prec))
8513 return fold_build1_loc (loc, code, type, TREE_OPERAND (op0, 0));
8515 /* If we have a sign-extension of a zero-extended value, we can
8516 replace that by a single zero-extension. */
8517 if (inside_int && inter_int && final_int
8518 && inside_prec < inter_prec && inter_prec < final_prec
8519 && inside_unsignedp && !inter_unsignedp)
8520 return fold_build1_loc (loc, code, type, TREE_OPERAND (op0, 0));
8522 /* Two conversions in a row are not needed unless:
8523 - some conversion is floating-point (overstrict for now), or
8524 - some conversion is a vector (overstrict for now), or
8525 - the intermediate type is narrower than both initial and
8527 - the intermediate type and innermost type differ in signedness,
8528 and the outermost type is wider than the intermediate, or
8529 - the initial type is a pointer type and the precisions of the
8530 intermediate and final types differ, or
8531 - the final type is a pointer type and the precisions of the
8532 initial and intermediate types differ. */
8533 if (! inside_float && ! inter_float && ! final_float
8534 && ! inside_vec && ! inter_vec && ! final_vec
8535 && (inter_prec >= inside_prec || inter_prec >= final_prec)
8536 && ! (inside_int && inter_int
8537 && inter_unsignedp != inside_unsignedp
8538 && inter_prec < final_prec)
8539 && ((inter_unsignedp && inter_prec > inside_prec)
8540 == (final_unsignedp && final_prec > inter_prec))
8541 && ! (inside_ptr && inter_prec != final_prec)
8542 && ! (final_ptr && inside_prec != inter_prec)
8543 && ! (final_prec != GET_MODE_BITSIZE (TYPE_MODE (type))
8544 && TYPE_MODE (type) == TYPE_MODE (inter_type)))
8545 return fold_build1_loc (loc, code, type, TREE_OPERAND (op0, 0));
8548 /* Handle (T *)&A.B.C for A being of type T and B and C
8549 living at offset zero. This occurs frequently in
8550 C++ upcasting and then accessing the base. */
8551 if (TREE_CODE (op0) == ADDR_EXPR
8552 && POINTER_TYPE_P (type)
8553 && handled_component_p (TREE_OPERAND (op0, 0)))
8555 HOST_WIDE_INT bitsize, bitpos;
8557 enum machine_mode mode;
8558 int unsignedp, volatilep;
8559 tree base = TREE_OPERAND (op0, 0);
8560 base = get_inner_reference (base, &bitsize, &bitpos, &offset,
8561 &mode, &unsignedp, &volatilep, false);
8562 /* If the reference was to a (constant) zero offset, we can use
8563 the address of the base if it has the same base type
8564 as the result type. */
8565 if (! offset && bitpos == 0
8566 && TYPE_MAIN_VARIANT (TREE_TYPE (type))
8567 == TYPE_MAIN_VARIANT (TREE_TYPE (base)))
8568 return fold_convert_loc (loc, type,
8569 build_fold_addr_expr_loc (loc, base));
8572 if (TREE_CODE (op0) == MODIFY_EXPR
8573 && TREE_CONSTANT (TREE_OPERAND (op0, 1))
8574 /* Detect assigning a bitfield. */
8575 && !(TREE_CODE (TREE_OPERAND (op0, 0)) == COMPONENT_REF
8577 (TREE_OPERAND (TREE_OPERAND (op0, 0), 1))))
8579 /* Don't leave an assignment inside a conversion
8580 unless assigning a bitfield. */
8581 tem = fold_build1_loc (loc, code, type, TREE_OPERAND (op0, 1));
8582 /* First do the assignment, then return converted constant. */
8583 tem = build2 (COMPOUND_EXPR, TREE_TYPE (tem), op0, tem);
8584 TREE_NO_WARNING (tem) = 1;
8585 TREE_USED (tem) = 1;
8586 SET_EXPR_LOCATION (tem, loc);
8590 /* Convert (T)(x & c) into (T)x & (T)c, if c is an integer
8591 constants (if x has signed type, the sign bit cannot be set
8592 in c). This folds extension into the BIT_AND_EXPR.
8593 ??? We don't do it for BOOLEAN_TYPE or ENUMERAL_TYPE because they
8594 very likely don't have maximal range for their precision and this
8595 transformation effectively doesn't preserve non-maximal ranges. */
8596 if (TREE_CODE (type) == INTEGER_TYPE
8597 && TREE_CODE (op0) == BIT_AND_EXPR
8598 && TREE_CODE (TREE_OPERAND (op0, 1)) == INTEGER_CST)
8600 tree and_expr = op0;
8601 tree and0 = TREE_OPERAND (and_expr, 0);
8602 tree and1 = TREE_OPERAND (and_expr, 1);
8605 if (TYPE_UNSIGNED (TREE_TYPE (and_expr))
8606 || (TYPE_PRECISION (type)
8607 <= TYPE_PRECISION (TREE_TYPE (and_expr))))
8609 else if (TYPE_PRECISION (TREE_TYPE (and1))
8610 <= HOST_BITS_PER_WIDE_INT
8611 && host_integerp (and1, 1))
8613 unsigned HOST_WIDE_INT cst;
8615 cst = tree_low_cst (and1, 1);
8616 cst &= (HOST_WIDE_INT) -1
8617 << (TYPE_PRECISION (TREE_TYPE (and1)) - 1);
8618 change = (cst == 0);
8619 #ifdef LOAD_EXTEND_OP
8621 && !flag_syntax_only
8622 && (LOAD_EXTEND_OP (TYPE_MODE (TREE_TYPE (and0)))
8625 tree uns = unsigned_type_for (TREE_TYPE (and0));
8626 and0 = fold_convert_loc (loc, uns, and0);
8627 and1 = fold_convert_loc (loc, uns, and1);
8633 tem = force_fit_type_double (type, TREE_INT_CST_LOW (and1),
8634 TREE_INT_CST_HIGH (and1), 0,
8635 TREE_OVERFLOW (and1));
8636 return fold_build2_loc (loc, BIT_AND_EXPR, type,
8637 fold_convert_loc (loc, type, and0), tem);
8641 /* Convert (T1)(X p+ Y) into ((T1)X p+ Y), for pointer type,
8642 when one of the new casts will fold away. Conservatively we assume
8643 that this happens when X or Y is NOP_EXPR or Y is INTEGER_CST. */
8644 if (POINTER_TYPE_P (type)
8645 && TREE_CODE (arg0) == POINTER_PLUS_EXPR
8646 && (TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST
8647 || TREE_CODE (TREE_OPERAND (arg0, 0)) == NOP_EXPR
8648 || TREE_CODE (TREE_OPERAND (arg0, 1)) == NOP_EXPR))
8650 tree arg00 = TREE_OPERAND (arg0, 0);
8651 tree arg01 = TREE_OPERAND (arg0, 1);
8653 return fold_build2_loc (loc,
8654 TREE_CODE (arg0), type,
8655 fold_convert_loc (loc, type, arg00),
8656 fold_convert_loc (loc, sizetype, arg01));
8659 /* Convert (T1)(~(T2)X) into ~(T1)X if T1 and T2 are integral types
8660 of the same precision, and X is an integer type not narrower than
8661 types T1 or T2, i.e. the cast (T2)X isn't an extension. */
8662 if (INTEGRAL_TYPE_P (type)
8663 && TREE_CODE (op0) == BIT_NOT_EXPR
8664 && INTEGRAL_TYPE_P (TREE_TYPE (op0))
8665 && CONVERT_EXPR_P (TREE_OPERAND (op0, 0))
8666 && TYPE_PRECISION (type) == TYPE_PRECISION (TREE_TYPE (op0)))
8668 tem = TREE_OPERAND (TREE_OPERAND (op0, 0), 0);
8669 if (INTEGRAL_TYPE_P (TREE_TYPE (tem))
8670 && TYPE_PRECISION (type) <= TYPE_PRECISION (TREE_TYPE (tem)))
8671 return fold_build1_loc (loc, BIT_NOT_EXPR, type,
8672 fold_convert_loc (loc, type, tem));
8675 /* Convert (T1)(X * Y) into (T1)X * (T1)Y if T1 is narrower than the
8676 type of X and Y (integer types only). */
8677 if (INTEGRAL_TYPE_P (type)
8678 && TREE_CODE (op0) == MULT_EXPR
8679 && INTEGRAL_TYPE_P (TREE_TYPE (op0))
8680 && TYPE_PRECISION (type) < TYPE_PRECISION (TREE_TYPE (op0)))
8682 /* Be careful not to introduce new overflows. */
8684 if (TYPE_OVERFLOW_WRAPS (type))
8687 mult_type = unsigned_type_for (type);
8689 if (TYPE_PRECISION (mult_type) < TYPE_PRECISION (TREE_TYPE (op0)))
8691 tem = fold_build2_loc (loc, MULT_EXPR, mult_type,
8692 fold_convert_loc (loc, mult_type,
8693 TREE_OPERAND (op0, 0)),
8694 fold_convert_loc (loc, mult_type,
8695 TREE_OPERAND (op0, 1)));
8696 return fold_convert_loc (loc, type, tem);
8700 tem = fold_convert_const (code, type, op0);
8701 return tem ? tem : NULL_TREE;
8703 case ADDR_SPACE_CONVERT_EXPR:
8704 if (integer_zerop (arg0))
8705 return fold_convert_const (code, type, arg0);
8708 case FIXED_CONVERT_EXPR:
8709 tem = fold_convert_const (code, type, arg0);
8710 return tem ? tem : NULL_TREE;
8712 case VIEW_CONVERT_EXPR:
8713 if (TREE_TYPE (op0) == type)
8715 if (TREE_CODE (op0) == VIEW_CONVERT_EXPR)
8716 return fold_build1_loc (loc, VIEW_CONVERT_EXPR,
8717 type, TREE_OPERAND (op0, 0));
8719 /* For integral conversions with the same precision or pointer
8720 conversions use a NOP_EXPR instead. */
8721 if ((INTEGRAL_TYPE_P (type)
8722 || POINTER_TYPE_P (type))
8723 && (INTEGRAL_TYPE_P (TREE_TYPE (op0))
8724 || POINTER_TYPE_P (TREE_TYPE (op0)))
8725 && TYPE_PRECISION (type) == TYPE_PRECISION (TREE_TYPE (op0)))
8726 return fold_convert_loc (loc, type, op0);
8728 /* Strip inner integral conversions that do not change the precision. */
8729 if (CONVERT_EXPR_P (op0)
8730 && (INTEGRAL_TYPE_P (TREE_TYPE (op0))
8731 || POINTER_TYPE_P (TREE_TYPE (op0)))
8732 && (INTEGRAL_TYPE_P (TREE_TYPE (TREE_OPERAND (op0, 0)))
8733 || POINTER_TYPE_P (TREE_TYPE (TREE_OPERAND (op0, 0))))
8734 && (TYPE_PRECISION (TREE_TYPE (op0))
8735 == TYPE_PRECISION (TREE_TYPE (TREE_OPERAND (op0, 0)))))
8736 return fold_build1_loc (loc, VIEW_CONVERT_EXPR,
8737 type, TREE_OPERAND (op0, 0));
8739 return fold_view_convert_expr (type, op0);
8742 tem = fold_negate_expr (loc, arg0);
8744 return fold_convert_loc (loc, type, tem);
8748 if (TREE_CODE (arg0) == INTEGER_CST || TREE_CODE (arg0) == REAL_CST)
8749 return fold_abs_const (arg0, type);
8750 else if (TREE_CODE (arg0) == NEGATE_EXPR)
8751 return fold_build1_loc (loc, ABS_EXPR, type, TREE_OPERAND (arg0, 0));
8752 /* Convert fabs((double)float) into (double)fabsf(float). */
8753 else if (TREE_CODE (arg0) == NOP_EXPR
8754 && TREE_CODE (type) == REAL_TYPE)
8756 tree targ0 = strip_float_extensions (arg0);
8758 return fold_convert_loc (loc, type,
8759 fold_build1_loc (loc, ABS_EXPR,
8763 /* ABS_EXPR<ABS_EXPR<x>> = ABS_EXPR<x> even if flag_wrapv is on. */
8764 else if (TREE_CODE (arg0) == ABS_EXPR)
8766 else if (tree_expr_nonnegative_p (arg0))
8769 /* Strip sign ops from argument. */
8770 if (TREE_CODE (type) == REAL_TYPE)
8772 tem = fold_strip_sign_ops (arg0);
8774 return fold_build1_loc (loc, ABS_EXPR, type,
8775 fold_convert_loc (loc, type, tem));
8780 if (TREE_CODE (TREE_TYPE (arg0)) != COMPLEX_TYPE)
8781 return fold_convert_loc (loc, type, arg0);
8782 if (TREE_CODE (arg0) == COMPLEX_EXPR)
8784 tree itype = TREE_TYPE (type);
8785 tree rpart = fold_convert_loc (loc, itype, TREE_OPERAND (arg0, 0));
8786 tree ipart = fold_convert_loc (loc, itype, TREE_OPERAND (arg0, 1));
8787 return fold_build2_loc (loc, COMPLEX_EXPR, type, rpart,
8788 negate_expr (ipart));
8790 if (TREE_CODE (arg0) == COMPLEX_CST)
8792 tree itype = TREE_TYPE (type);
8793 tree rpart = fold_convert_loc (loc, itype, TREE_REALPART (arg0));
8794 tree ipart = fold_convert_loc (loc, itype, TREE_IMAGPART (arg0));
8795 return build_complex (type, rpart, negate_expr (ipart));
8797 if (TREE_CODE (arg0) == CONJ_EXPR)
8798 return fold_convert_loc (loc, type, TREE_OPERAND (arg0, 0));
8802 if (TREE_CODE (arg0) == INTEGER_CST)
8803 return fold_not_const (arg0, type);
8804 else if (TREE_CODE (arg0) == BIT_NOT_EXPR)
8805 return fold_convert_loc (loc, type, TREE_OPERAND (arg0, 0));
8806 /* Convert ~ (-A) to A - 1. */
8807 else if (INTEGRAL_TYPE_P (type) && TREE_CODE (arg0) == NEGATE_EXPR)
8808 return fold_build2_loc (loc, MINUS_EXPR, type,
8809 fold_convert_loc (loc, type, TREE_OPERAND (arg0, 0)),
8810 build_int_cst (type, 1));
8811 /* Convert ~ (A - 1) or ~ (A + -1) to -A. */
8812 else if (INTEGRAL_TYPE_P (type)
8813 && ((TREE_CODE (arg0) == MINUS_EXPR
8814 && integer_onep (TREE_OPERAND (arg0, 1)))
8815 || (TREE_CODE (arg0) == PLUS_EXPR
8816 && integer_all_onesp (TREE_OPERAND (arg0, 1)))))
8817 return fold_build1_loc (loc, NEGATE_EXPR, type,
8818 fold_convert_loc (loc, type,
8819 TREE_OPERAND (arg0, 0)));
8820 /* Convert ~(X ^ Y) to ~X ^ Y or X ^ ~Y if ~X or ~Y simplify. */
8821 else if (TREE_CODE (arg0) == BIT_XOR_EXPR
8822 && (tem = fold_unary_loc (loc, BIT_NOT_EXPR, type,
8823 fold_convert_loc (loc, type,
8824 TREE_OPERAND (arg0, 0)))))
8825 return fold_build2_loc (loc, BIT_XOR_EXPR, type, tem,
8826 fold_convert_loc (loc, type,
8827 TREE_OPERAND (arg0, 1)));
8828 else if (TREE_CODE (arg0) == BIT_XOR_EXPR
8829 && (tem = fold_unary_loc (loc, BIT_NOT_EXPR, type,
8830 fold_convert_loc (loc, type,
8831 TREE_OPERAND (arg0, 1)))))
8832 return fold_build2_loc (loc, BIT_XOR_EXPR, type,
8833 fold_convert_loc (loc, type,
8834 TREE_OPERAND (arg0, 0)), tem);
8835 /* Perform BIT_NOT_EXPR on each element individually. */
8836 else if (TREE_CODE (arg0) == VECTOR_CST)
8838 tree elements = TREE_VECTOR_CST_ELTS (arg0), elem, list = NULL_TREE;
8839 int count = TYPE_VECTOR_SUBPARTS (type), i;
8841 for (i = 0; i < count; i++)
8845 elem = TREE_VALUE (elements);
8846 elem = fold_unary_loc (loc, BIT_NOT_EXPR, TREE_TYPE (type), elem);
8847 if (elem == NULL_TREE)
8849 elements = TREE_CHAIN (elements);
8852 elem = build_int_cst (TREE_TYPE (type), -1);
8853 list = tree_cons (NULL_TREE, elem, list);
8856 return build_vector (type, nreverse (list));
8861 case TRUTH_NOT_EXPR:
8862 /* The argument to invert_truthvalue must have Boolean type. */
8863 if (TREE_CODE (TREE_TYPE (arg0)) != BOOLEAN_TYPE)
8864 arg0 = fold_convert_loc (loc, boolean_type_node, arg0);
8866 /* Note that the operand of this must be an int
8867 and its values must be 0 or 1.
8868 ("true" is a fixed value perhaps depending on the language,
8869 but we don't handle values other than 1 correctly yet.) */
8870 tem = fold_truth_not_expr (loc, arg0);
8873 return fold_convert_loc (loc, type, tem);
8876 if (TREE_CODE (TREE_TYPE (arg0)) != COMPLEX_TYPE)
8877 return fold_convert_loc (loc, type, arg0);
8878 if (TREE_CODE (arg0) == COMPLEX_EXPR)
8879 return omit_one_operand_loc (loc, type, TREE_OPERAND (arg0, 0),
8880 TREE_OPERAND (arg0, 1));
8881 if (TREE_CODE (arg0) == COMPLEX_CST)
8882 return fold_convert_loc (loc, type, TREE_REALPART (arg0));
8883 if (TREE_CODE (arg0) == PLUS_EXPR || TREE_CODE (arg0) == MINUS_EXPR)
8885 tree itype = TREE_TYPE (TREE_TYPE (arg0));
8886 tem = fold_build2_loc (loc, TREE_CODE (arg0), itype,
8887 fold_build1_loc (loc, REALPART_EXPR, itype,
8888 TREE_OPERAND (arg0, 0)),
8889 fold_build1_loc (loc, REALPART_EXPR, itype,
8890 TREE_OPERAND (arg0, 1)));
8891 return fold_convert_loc (loc, type, tem);
8893 if (TREE_CODE (arg0) == CONJ_EXPR)
8895 tree itype = TREE_TYPE (TREE_TYPE (arg0));
8896 tem = fold_build1_loc (loc, REALPART_EXPR, itype,
8897 TREE_OPERAND (arg0, 0));
8898 return fold_convert_loc (loc, type, tem);
8900 if (TREE_CODE (arg0) == CALL_EXPR)
8902 tree fn = get_callee_fndecl (arg0);
8903 if (fn && DECL_BUILT_IN_CLASS (fn) == BUILT_IN_NORMAL)
8904 switch (DECL_FUNCTION_CODE (fn))
8906 CASE_FLT_FN (BUILT_IN_CEXPI):
8907 fn = mathfn_built_in (type, BUILT_IN_COS);
8909 return build_call_expr_loc (loc, fn, 1, CALL_EXPR_ARG (arg0, 0));
8919 if (TREE_CODE (TREE_TYPE (arg0)) != COMPLEX_TYPE)
8920 return fold_convert_loc (loc, type, integer_zero_node);
8921 if (TREE_CODE (arg0) == COMPLEX_EXPR)
8922 return omit_one_operand_loc (loc, type, TREE_OPERAND (arg0, 1),
8923 TREE_OPERAND (arg0, 0));
8924 if (TREE_CODE (arg0) == COMPLEX_CST)
8925 return fold_convert_loc (loc, type, TREE_IMAGPART (arg0));
8926 if (TREE_CODE (arg0) == PLUS_EXPR || TREE_CODE (arg0) == MINUS_EXPR)
8928 tree itype = TREE_TYPE (TREE_TYPE (arg0));
8929 tem = fold_build2_loc (loc, TREE_CODE (arg0), itype,
8930 fold_build1_loc (loc, IMAGPART_EXPR, itype,
8931 TREE_OPERAND (arg0, 0)),
8932 fold_build1_loc (loc, IMAGPART_EXPR, itype,
8933 TREE_OPERAND (arg0, 1)));
8934 return fold_convert_loc (loc, type, tem);
8936 if (TREE_CODE (arg0) == CONJ_EXPR)
8938 tree itype = TREE_TYPE (TREE_TYPE (arg0));
8939 tem = fold_build1_loc (loc, IMAGPART_EXPR, itype, TREE_OPERAND (arg0, 0));
8940 return fold_convert_loc (loc, type, negate_expr (tem));
8942 if (TREE_CODE (arg0) == CALL_EXPR)
8944 tree fn = get_callee_fndecl (arg0);
8945 if (fn && DECL_BUILT_IN_CLASS (fn) == BUILT_IN_NORMAL)
8946 switch (DECL_FUNCTION_CODE (fn))
8948 CASE_FLT_FN (BUILT_IN_CEXPI):
8949 fn = mathfn_built_in (type, BUILT_IN_SIN);
8951 return build_call_expr_loc (loc, fn, 1, CALL_EXPR_ARG (arg0, 0));
8961 /* Fold *&X to X if X is an lvalue. */
8962 if (TREE_CODE (op0) == ADDR_EXPR)
8964 tree op00 = TREE_OPERAND (op0, 0);
8965 if ((TREE_CODE (op00) == VAR_DECL
8966 || TREE_CODE (op00) == PARM_DECL
8967 || TREE_CODE (op00) == RESULT_DECL)
8968 && !TREE_READONLY (op00))
8975 } /* switch (code) */
8979 /* If the operation was a conversion do _not_ mark a resulting constant
8980 with TREE_OVERFLOW if the original constant was not. These conversions
8981 have implementation defined behavior and retaining the TREE_OVERFLOW
8982 flag here would confuse later passes such as VRP. */
8984 fold_unary_ignore_overflow_loc (location_t loc, enum tree_code code,
8985 tree type, tree op0)
8987 tree res = fold_unary_loc (loc, code, type, op0);
8989 && TREE_CODE (res) == INTEGER_CST
8990 && TREE_CODE (op0) == INTEGER_CST
8991 && CONVERT_EXPR_CODE_P (code))
8992 TREE_OVERFLOW (res) = TREE_OVERFLOW (op0);
8997 /* Fold a binary expression of code CODE and type TYPE with operands
8998 OP0 and OP1, containing either a MIN-MAX or a MAX-MIN combination.
8999 Return the folded expression if folding is successful. Otherwise,
9000 return NULL_TREE. */
9003 fold_minmax (location_t loc, enum tree_code code, tree type, tree op0, tree op1)
9005 enum tree_code compl_code;
9007 if (code == MIN_EXPR)
9008 compl_code = MAX_EXPR;
9009 else if (code == MAX_EXPR)
9010 compl_code = MIN_EXPR;
9014 /* MIN (MAX (a, b), b) == b. */
9015 if (TREE_CODE (op0) == compl_code
9016 && operand_equal_p (TREE_OPERAND (op0, 1), op1, 0))
9017 return omit_one_operand_loc (loc, type, op1, TREE_OPERAND (op0, 0));
9019 /* MIN (MAX (b, a), b) == b. */
9020 if (TREE_CODE (op0) == compl_code
9021 && operand_equal_p (TREE_OPERAND (op0, 0), op1, 0)
9022 && reorder_operands_p (TREE_OPERAND (op0, 1), op1))
9023 return omit_one_operand_loc (loc, type, op1, TREE_OPERAND (op0, 1));
9025 /* MIN (a, MAX (a, b)) == a. */
9026 if (TREE_CODE (op1) == compl_code
9027 && operand_equal_p (op0, TREE_OPERAND (op1, 0), 0)
9028 && reorder_operands_p (op0, TREE_OPERAND (op1, 1)))
9029 return omit_one_operand_loc (loc, type, op0, TREE_OPERAND (op1, 1));
9031 /* MIN (a, MAX (b, a)) == a. */
9032 if (TREE_CODE (op1) == compl_code
9033 && operand_equal_p (op0, TREE_OPERAND (op1, 1), 0)
9034 && reorder_operands_p (op0, TREE_OPERAND (op1, 0)))
9035 return omit_one_operand_loc (loc, type, op0, TREE_OPERAND (op1, 0));
9040 /* Helper that tries to canonicalize the comparison ARG0 CODE ARG1
9041 by changing CODE to reduce the magnitude of constants involved in
9042 ARG0 of the comparison.
9043 Returns a canonicalized comparison tree if a simplification was
9044 possible, otherwise returns NULL_TREE.
9045 Set *STRICT_OVERFLOW_P to true if the canonicalization is only
9046 valid if signed overflow is undefined. */
9049 maybe_canonicalize_comparison_1 (location_t loc, enum tree_code code, tree type,
9050 tree arg0, tree arg1,
9051 bool *strict_overflow_p)
9053 enum tree_code code0 = TREE_CODE (arg0);
9054 tree t, cst0 = NULL_TREE;
9058 /* Match A +- CST code arg1 and CST code arg1. We can change the
9059 first form only if overflow is undefined. */
9060 if (!((TYPE_OVERFLOW_UNDEFINED (TREE_TYPE (arg0))
9061 /* In principle pointers also have undefined overflow behavior,
9062 but that causes problems elsewhere. */
9063 && !POINTER_TYPE_P (TREE_TYPE (arg0))
9064 && (code0 == MINUS_EXPR
9065 || code0 == PLUS_EXPR)
9066 && TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST)
9067 || code0 == INTEGER_CST))
9070 /* Identify the constant in arg0 and its sign. */
9071 if (code0 == INTEGER_CST)
9074 cst0 = TREE_OPERAND (arg0, 1);
9075 sgn0 = tree_int_cst_sgn (cst0);
9077 /* Overflowed constants and zero will cause problems. */
9078 if (integer_zerop (cst0)
9079 || TREE_OVERFLOW (cst0))
9082 /* See if we can reduce the magnitude of the constant in
9083 arg0 by changing the comparison code. */
9084 if (code0 == INTEGER_CST)
9086 /* CST <= arg1 -> CST-1 < arg1. */
9087 if (code == LE_EXPR && sgn0 == 1)
9089 /* -CST < arg1 -> -CST-1 <= arg1. */
9090 else if (code == LT_EXPR && sgn0 == -1)
9092 /* CST > arg1 -> CST-1 >= arg1. */
9093 else if (code == GT_EXPR && sgn0 == 1)
9095 /* -CST >= arg1 -> -CST-1 > arg1. */
9096 else if (code == GE_EXPR && sgn0 == -1)
9100 /* arg1 code' CST' might be more canonical. */
9105 /* A - CST < arg1 -> A - CST-1 <= arg1. */
9107 && code0 == ((sgn0 == -1) ? PLUS_EXPR : MINUS_EXPR))
9109 /* A + CST > arg1 -> A + CST-1 >= arg1. */
9110 else if (code == GT_EXPR
9111 && code0 == ((sgn0 == -1) ? MINUS_EXPR : PLUS_EXPR))
9113 /* A + CST <= arg1 -> A + CST-1 < arg1. */
9114 else if (code == LE_EXPR
9115 && code0 == ((sgn0 == -1) ? MINUS_EXPR : PLUS_EXPR))
9117 /* A - CST >= arg1 -> A - CST-1 > arg1. */
9118 else if (code == GE_EXPR
9119 && code0 == ((sgn0 == -1) ? PLUS_EXPR : MINUS_EXPR))
9123 *strict_overflow_p = true;
9126 /* Now build the constant reduced in magnitude. But not if that
9127 would produce one outside of its types range. */
9128 if (INTEGRAL_TYPE_P (TREE_TYPE (cst0))
9130 && TYPE_MIN_VALUE (TREE_TYPE (cst0))
9131 && tree_int_cst_equal (cst0, TYPE_MIN_VALUE (TREE_TYPE (cst0))))
9133 && TYPE_MAX_VALUE (TREE_TYPE (cst0))
9134 && tree_int_cst_equal (cst0, TYPE_MAX_VALUE (TREE_TYPE (cst0))))))
9135 /* We cannot swap the comparison here as that would cause us to
9136 endlessly recurse. */
9139 t = int_const_binop (sgn0 == -1 ? PLUS_EXPR : MINUS_EXPR,
9140 cst0, build_int_cst (TREE_TYPE (cst0), 1), 0);
9141 if (code0 != INTEGER_CST)
9142 t = fold_build2_loc (loc, code0, TREE_TYPE (arg0), TREE_OPERAND (arg0, 0), t);
9144 /* If swapping might yield to a more canonical form, do so. */
9146 return fold_build2_loc (loc, swap_tree_comparison (code), type, arg1, t);
9148 return fold_build2_loc (loc, code, type, t, arg1);
9151 /* Canonicalize the comparison ARG0 CODE ARG1 with type TYPE with undefined
9152 overflow further. Try to decrease the magnitude of constants involved
9153 by changing LE_EXPR and GE_EXPR to LT_EXPR and GT_EXPR or vice versa
9154 and put sole constants at the second argument position.
9155 Returns the canonicalized tree if changed, otherwise NULL_TREE. */
9158 maybe_canonicalize_comparison (location_t loc, enum tree_code code, tree type,
9159 tree arg0, tree arg1)
9162 bool strict_overflow_p;
9163 const char * const warnmsg = G_("assuming signed overflow does not occur "
9164 "when reducing constant in comparison");
9166 /* Try canonicalization by simplifying arg0. */
9167 strict_overflow_p = false;
9168 t = maybe_canonicalize_comparison_1 (loc, code, type, arg0, arg1,
9169 &strict_overflow_p);
9172 if (strict_overflow_p)
9173 fold_overflow_warning (warnmsg, WARN_STRICT_OVERFLOW_MAGNITUDE);
9177 /* Try canonicalization by simplifying arg1 using the swapped
9179 code = swap_tree_comparison (code);
9180 strict_overflow_p = false;
9181 t = maybe_canonicalize_comparison_1 (loc, code, type, arg1, arg0,
9182 &strict_overflow_p);
9183 if (t && strict_overflow_p)
9184 fold_overflow_warning (warnmsg, WARN_STRICT_OVERFLOW_MAGNITUDE);
9188 /* Return whether BASE + OFFSET + BITPOS may wrap around the address
9189 space. This is used to avoid issuing overflow warnings for
9190 expressions like &p->x which can not wrap. */
9193 pointer_may_wrap_p (tree base, tree offset, HOST_WIDE_INT bitpos)
9195 unsigned HOST_WIDE_INT offset_low, total_low;
9196 HOST_WIDE_INT size, offset_high, total_high;
9198 if (!POINTER_TYPE_P (TREE_TYPE (base)))
9204 if (offset == NULL_TREE)
9209 else if (TREE_CODE (offset) != INTEGER_CST || TREE_OVERFLOW (offset))
9213 offset_low = TREE_INT_CST_LOW (offset);
9214 offset_high = TREE_INT_CST_HIGH (offset);
9217 if (add_double_with_sign (offset_low, offset_high,
9218 bitpos / BITS_PER_UNIT, 0,
9219 &total_low, &total_high,
9223 if (total_high != 0)
9226 size = int_size_in_bytes (TREE_TYPE (TREE_TYPE (base)));
9230 /* We can do slightly better for SIZE if we have an ADDR_EXPR of an
9232 if (TREE_CODE (base) == ADDR_EXPR)
9234 HOST_WIDE_INT base_size;
9236 base_size = int_size_in_bytes (TREE_TYPE (TREE_OPERAND (base, 0)));
9237 if (base_size > 0 && size < base_size)
9241 return total_low > (unsigned HOST_WIDE_INT) size;
9244 /* Subroutine of fold_binary. This routine performs all of the
9245 transformations that are common to the equality/inequality
9246 operators (EQ_EXPR and NE_EXPR) and the ordering operators
9247 (LT_EXPR, LE_EXPR, GE_EXPR and GT_EXPR). Callers other than
9248 fold_binary should call fold_binary. Fold a comparison with
9249 tree code CODE and type TYPE with operands OP0 and OP1. Return
9250 the folded comparison or NULL_TREE. */
9253 fold_comparison (location_t loc, enum tree_code code, tree type,
9256 tree arg0, arg1, tem;
9261 STRIP_SIGN_NOPS (arg0);
9262 STRIP_SIGN_NOPS (arg1);
9264 tem = fold_relational_const (code, type, arg0, arg1);
9265 if (tem != NULL_TREE)
9268 /* If one arg is a real or integer constant, put it last. */
9269 if (tree_swap_operands_p (arg0, arg1, true))
9270 return fold_build2_loc (loc, swap_tree_comparison (code), type, op1, op0);
9272 /* Transform comparisons of the form X +- C1 CMP C2 to X CMP C2 +- C1. */
9273 if ((TREE_CODE (arg0) == PLUS_EXPR || TREE_CODE (arg0) == MINUS_EXPR)
9274 && (TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST
9275 && !TREE_OVERFLOW (TREE_OPERAND (arg0, 1))
9276 && TYPE_OVERFLOW_UNDEFINED (TREE_TYPE (arg1)))
9277 && (TREE_CODE (arg1) == INTEGER_CST
9278 && !TREE_OVERFLOW (arg1)))
9280 tree const1 = TREE_OPERAND (arg0, 1);
9282 tree variable = TREE_OPERAND (arg0, 0);
9285 lhs_add = TREE_CODE (arg0) != PLUS_EXPR;
9287 lhs = fold_build2_loc (loc, lhs_add ? PLUS_EXPR : MINUS_EXPR,
9288 TREE_TYPE (arg1), const2, const1);
9290 /* If the constant operation overflowed this can be
9291 simplified as a comparison against INT_MAX/INT_MIN. */
9292 if (TREE_CODE (lhs) == INTEGER_CST
9293 && TREE_OVERFLOW (lhs))
9295 int const1_sgn = tree_int_cst_sgn (const1);
9296 enum tree_code code2 = code;
9298 /* Get the sign of the constant on the lhs if the
9299 operation were VARIABLE + CONST1. */
9300 if (TREE_CODE (arg0) == MINUS_EXPR)
9301 const1_sgn = -const1_sgn;
9303 /* The sign of the constant determines if we overflowed
9304 INT_MAX (const1_sgn == -1) or INT_MIN (const1_sgn == 1).
9305 Canonicalize to the INT_MIN overflow by swapping the comparison
9307 if (const1_sgn == -1)
9308 code2 = swap_tree_comparison (code);
9310 /* We now can look at the canonicalized case
9311 VARIABLE + 1 CODE2 INT_MIN
9312 and decide on the result. */
9313 if (code2 == LT_EXPR
9315 || code2 == EQ_EXPR)
9316 return omit_one_operand_loc (loc, type, boolean_false_node, variable);
9317 else if (code2 == NE_EXPR
9319 || code2 == GT_EXPR)
9320 return omit_one_operand_loc (loc, type, boolean_true_node, variable);
9323 if (TREE_CODE (lhs) == TREE_CODE (arg1)
9324 && (TREE_CODE (lhs) != INTEGER_CST
9325 || !TREE_OVERFLOW (lhs)))
9327 fold_overflow_warning (("assuming signed overflow does not occur "
9328 "when changing X +- C1 cmp C2 to "
9330 WARN_STRICT_OVERFLOW_COMPARISON);
9331 return fold_build2_loc (loc, code, type, variable, lhs);
9335 /* For comparisons of pointers we can decompose it to a compile time
9336 comparison of the base objects and the offsets into the object.
9337 This requires at least one operand being an ADDR_EXPR or a
9338 POINTER_PLUS_EXPR to do more than the operand_equal_p test below. */
9339 if (POINTER_TYPE_P (TREE_TYPE (arg0))
9340 && (TREE_CODE (arg0) == ADDR_EXPR
9341 || TREE_CODE (arg1) == ADDR_EXPR
9342 || TREE_CODE (arg0) == POINTER_PLUS_EXPR
9343 || TREE_CODE (arg1) == POINTER_PLUS_EXPR))
9345 tree base0, base1, offset0 = NULL_TREE, offset1 = NULL_TREE;
9346 HOST_WIDE_INT bitsize, bitpos0 = 0, bitpos1 = 0;
9347 enum machine_mode mode;
9348 int volatilep, unsignedp;
9349 bool indirect_base0 = false, indirect_base1 = false;
9351 /* Get base and offset for the access. Strip ADDR_EXPR for
9352 get_inner_reference, but put it back by stripping INDIRECT_REF
9353 off the base object if possible. indirect_baseN will be true
9354 if baseN is not an address but refers to the object itself. */
9356 if (TREE_CODE (arg0) == ADDR_EXPR)
9358 base0 = get_inner_reference (TREE_OPERAND (arg0, 0),
9359 &bitsize, &bitpos0, &offset0, &mode,
9360 &unsignedp, &volatilep, false);
9361 if (TREE_CODE (base0) == INDIRECT_REF)
9362 base0 = TREE_OPERAND (base0, 0);
9364 indirect_base0 = true;
9366 else if (TREE_CODE (arg0) == POINTER_PLUS_EXPR)
9368 base0 = TREE_OPERAND (arg0, 0);
9369 offset0 = TREE_OPERAND (arg0, 1);
9373 if (TREE_CODE (arg1) == ADDR_EXPR)
9375 base1 = get_inner_reference (TREE_OPERAND (arg1, 0),
9376 &bitsize, &bitpos1, &offset1, &mode,
9377 &unsignedp, &volatilep, false);
9378 if (TREE_CODE (base1) == INDIRECT_REF)
9379 base1 = TREE_OPERAND (base1, 0);
9381 indirect_base1 = true;
9383 else if (TREE_CODE (arg1) == POINTER_PLUS_EXPR)
9385 base1 = TREE_OPERAND (arg1, 0);
9386 offset1 = TREE_OPERAND (arg1, 1);
9389 /* If we have equivalent bases we might be able to simplify. */
9390 if (indirect_base0 == indirect_base1
9391 && operand_equal_p (base0, base1, 0))
9393 /* We can fold this expression to a constant if the non-constant
9394 offset parts are equal. */
9395 if ((offset0 == offset1
9396 || (offset0 && offset1
9397 && operand_equal_p (offset0, offset1, 0)))
9400 || POINTER_TYPE_OVERFLOW_UNDEFINED))
9405 && bitpos0 != bitpos1
9406 && (pointer_may_wrap_p (base0, offset0, bitpos0)
9407 || pointer_may_wrap_p (base1, offset1, bitpos1)))
9408 fold_overflow_warning (("assuming pointer wraparound does not "
9409 "occur when comparing P +- C1 with "
9411 WARN_STRICT_OVERFLOW_CONDITIONAL);
9416 return constant_boolean_node (bitpos0 == bitpos1, type);
9418 return constant_boolean_node (bitpos0 != bitpos1, type);
9420 return constant_boolean_node (bitpos0 < bitpos1, type);
9422 return constant_boolean_node (bitpos0 <= bitpos1, type);
9424 return constant_boolean_node (bitpos0 >= bitpos1, type);
9426 return constant_boolean_node (bitpos0 > bitpos1, type);
9430 /* We can simplify the comparison to a comparison of the variable
9431 offset parts if the constant offset parts are equal.
9432 Be careful to use signed size type here because otherwise we
9433 mess with array offsets in the wrong way. This is possible
9434 because pointer arithmetic is restricted to retain within an
9435 object and overflow on pointer differences is undefined as of
9436 6.5.6/8 and /9 with respect to the signed ptrdiff_t. */
9437 else if (bitpos0 == bitpos1
9438 && ((code == EQ_EXPR || code == NE_EXPR)
9439 || POINTER_TYPE_OVERFLOW_UNDEFINED))
9441 tree signed_size_type_node;
9442 signed_size_type_node = signed_type_for (size_type_node);
9444 /* By converting to signed size type we cover middle-end pointer
9445 arithmetic which operates on unsigned pointer types of size
9446 type size and ARRAY_REF offsets which are properly sign or
9447 zero extended from their type in case it is narrower than
9449 if (offset0 == NULL_TREE)
9450 offset0 = build_int_cst (signed_size_type_node, 0);
9452 offset0 = fold_convert_loc (loc, signed_size_type_node,
9454 if (offset1 == NULL_TREE)
9455 offset1 = build_int_cst (signed_size_type_node, 0);
9457 offset1 = fold_convert_loc (loc, signed_size_type_node,
9462 && (pointer_may_wrap_p (base0, offset0, bitpos0)
9463 || pointer_may_wrap_p (base1, offset1, bitpos1)))
9464 fold_overflow_warning (("assuming pointer wraparound does not "
9465 "occur when comparing P +- C1 with "
9467 WARN_STRICT_OVERFLOW_COMPARISON);
9469 return fold_build2_loc (loc, code, type, offset0, offset1);
9472 /* For non-equal bases we can simplify if they are addresses
9473 of local binding decls or constants. */
9474 else if (indirect_base0 && indirect_base1
9475 /* We know that !operand_equal_p (base0, base1, 0)
9476 because the if condition was false. But make
9477 sure two decls are not the same. */
9479 && TREE_CODE (arg0) == ADDR_EXPR
9480 && TREE_CODE (arg1) == ADDR_EXPR
9481 && (((TREE_CODE (base0) == VAR_DECL
9482 || TREE_CODE (base0) == PARM_DECL)
9483 && (targetm.binds_local_p (base0)
9484 || CONSTANT_CLASS_P (base1)))
9485 || CONSTANT_CLASS_P (base0))
9486 && (((TREE_CODE (base1) == VAR_DECL
9487 || TREE_CODE (base1) == PARM_DECL)
9488 && (targetm.binds_local_p (base1)
9489 || CONSTANT_CLASS_P (base0)))
9490 || CONSTANT_CLASS_P (base1)))
9492 if (code == EQ_EXPR)
9493 return omit_two_operands_loc (loc, type, boolean_false_node,
9495 else if (code == NE_EXPR)
9496 return omit_two_operands_loc (loc, type, boolean_true_node,
9499 /* For equal offsets we can simplify to a comparison of the
9501 else if (bitpos0 == bitpos1
9503 ? base0 != TREE_OPERAND (arg0, 0) : base0 != arg0)
9505 ? base1 != TREE_OPERAND (arg1, 0) : base1 != arg1)
9506 && ((offset0 == offset1)
9507 || (offset0 && offset1
9508 && operand_equal_p (offset0, offset1, 0))))
9511 base0 = build_fold_addr_expr_loc (loc, base0);
9513 base1 = build_fold_addr_expr_loc (loc, base1);
9514 return fold_build2_loc (loc, code, type, base0, base1);
9518 /* Transform comparisons of the form X +- C1 CMP Y +- C2 to
9519 X CMP Y +- C2 +- C1 for signed X, Y. This is valid if
9520 the resulting offset is smaller in absolute value than the
9522 if (TYPE_OVERFLOW_UNDEFINED (TREE_TYPE (arg0))
9523 && (TREE_CODE (arg0) == PLUS_EXPR || TREE_CODE (arg0) == MINUS_EXPR)
9524 && (TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST
9525 && !TREE_OVERFLOW (TREE_OPERAND (arg0, 1)))
9526 && (TREE_CODE (arg1) == PLUS_EXPR || TREE_CODE (arg1) == MINUS_EXPR)
9527 && (TREE_CODE (TREE_OPERAND (arg1, 1)) == INTEGER_CST
9528 && !TREE_OVERFLOW (TREE_OPERAND (arg1, 1))))
9530 tree const1 = TREE_OPERAND (arg0, 1);
9531 tree const2 = TREE_OPERAND (arg1, 1);
9532 tree variable1 = TREE_OPERAND (arg0, 0);
9533 tree variable2 = TREE_OPERAND (arg1, 0);
9535 const char * const warnmsg = G_("assuming signed overflow does not "
9536 "occur when combining constants around "
9539 /* Put the constant on the side where it doesn't overflow and is
9540 of lower absolute value than before. */
9541 cst = int_const_binop (TREE_CODE (arg0) == TREE_CODE (arg1)
9542 ? MINUS_EXPR : PLUS_EXPR,
9544 if (!TREE_OVERFLOW (cst)
9545 && tree_int_cst_compare (const2, cst) == tree_int_cst_sgn (const2))
9547 fold_overflow_warning (warnmsg, WARN_STRICT_OVERFLOW_COMPARISON);
9548 return fold_build2_loc (loc, code, type,
9550 fold_build2_loc (loc,
9551 TREE_CODE (arg1), TREE_TYPE (arg1),
9555 cst = int_const_binop (TREE_CODE (arg0) == TREE_CODE (arg1)
9556 ? MINUS_EXPR : PLUS_EXPR,
9558 if (!TREE_OVERFLOW (cst)
9559 && tree_int_cst_compare (const1, cst) == tree_int_cst_sgn (const1))
9561 fold_overflow_warning (warnmsg, WARN_STRICT_OVERFLOW_COMPARISON);
9562 return fold_build2_loc (loc, code, type,
9563 fold_build2_loc (loc, TREE_CODE (arg0), TREE_TYPE (arg0),
9569 /* Transform comparisons of the form X * C1 CMP 0 to X CMP 0 in the
9570 signed arithmetic case. That form is created by the compiler
9571 often enough for folding it to be of value. One example is in
9572 computing loop trip counts after Operator Strength Reduction. */
9573 if (TYPE_OVERFLOW_UNDEFINED (TREE_TYPE (arg0))
9574 && TREE_CODE (arg0) == MULT_EXPR
9575 && (TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST
9576 && !TREE_OVERFLOW (TREE_OPERAND (arg0, 1)))
9577 && integer_zerop (arg1))
9579 tree const1 = TREE_OPERAND (arg0, 1);
9580 tree const2 = arg1; /* zero */
9581 tree variable1 = TREE_OPERAND (arg0, 0);
9582 enum tree_code cmp_code = code;
9584 /* Handle unfolded multiplication by zero. */
9585 if (integer_zerop (const1))
9586 return fold_build2_loc (loc, cmp_code, type, const1, const2);
9588 fold_overflow_warning (("assuming signed overflow does not occur when "
9589 "eliminating multiplication in comparison "
9591 WARN_STRICT_OVERFLOW_COMPARISON);
9593 /* If const1 is negative we swap the sense of the comparison. */
9594 if (tree_int_cst_sgn (const1) < 0)
9595 cmp_code = swap_tree_comparison (cmp_code);
9597 return fold_build2_loc (loc, cmp_code, type, variable1, const2);
9600 tem = maybe_canonicalize_comparison (loc, code, type, op0, op1);
9604 if (FLOAT_TYPE_P (TREE_TYPE (arg0)))
9606 tree targ0 = strip_float_extensions (arg0);
9607 tree targ1 = strip_float_extensions (arg1);
9608 tree newtype = TREE_TYPE (targ0);
9610 if (TYPE_PRECISION (TREE_TYPE (targ1)) > TYPE_PRECISION (newtype))
9611 newtype = TREE_TYPE (targ1);
9613 /* Fold (double)float1 CMP (double)float2 into float1 CMP float2. */
9614 if (TYPE_PRECISION (newtype) < TYPE_PRECISION (TREE_TYPE (arg0)))
9615 return fold_build2_loc (loc, code, type,
9616 fold_convert_loc (loc, newtype, targ0),
9617 fold_convert_loc (loc, newtype, targ1));
9619 /* (-a) CMP (-b) -> b CMP a */
9620 if (TREE_CODE (arg0) == NEGATE_EXPR
9621 && TREE_CODE (arg1) == NEGATE_EXPR)
9622 return fold_build2_loc (loc, code, type, TREE_OPERAND (arg1, 0),
9623 TREE_OPERAND (arg0, 0));
9625 if (TREE_CODE (arg1) == REAL_CST)
9627 REAL_VALUE_TYPE cst;
9628 cst = TREE_REAL_CST (arg1);
9630 /* (-a) CMP CST -> a swap(CMP) (-CST) */
9631 if (TREE_CODE (arg0) == NEGATE_EXPR)
9632 return fold_build2_loc (loc, swap_tree_comparison (code), type,
9633 TREE_OPERAND (arg0, 0),
9634 build_real (TREE_TYPE (arg1),
9635 REAL_VALUE_NEGATE (cst)));
9637 /* IEEE doesn't distinguish +0 and -0 in comparisons. */
9638 /* a CMP (-0) -> a CMP 0 */
9639 if (REAL_VALUE_MINUS_ZERO (cst))
9640 return fold_build2_loc (loc, code, type, arg0,
9641 build_real (TREE_TYPE (arg1), dconst0));
9643 /* x != NaN is always true, other ops are always false. */
9644 if (REAL_VALUE_ISNAN (cst)
9645 && ! HONOR_SNANS (TYPE_MODE (TREE_TYPE (arg1))))
9647 tem = (code == NE_EXPR) ? integer_one_node : integer_zero_node;
9648 return omit_one_operand_loc (loc, type, tem, arg0);
9651 /* Fold comparisons against infinity. */
9652 if (REAL_VALUE_ISINF (cst)
9653 && MODE_HAS_INFINITIES (TYPE_MODE (TREE_TYPE (arg1))))
9655 tem = fold_inf_compare (loc, code, type, arg0, arg1);
9656 if (tem != NULL_TREE)
9661 /* If this is a comparison of a real constant with a PLUS_EXPR
9662 or a MINUS_EXPR of a real constant, we can convert it into a
9663 comparison with a revised real constant as long as no overflow
9664 occurs when unsafe_math_optimizations are enabled. */
9665 if (flag_unsafe_math_optimizations
9666 && TREE_CODE (arg1) == REAL_CST
9667 && (TREE_CODE (arg0) == PLUS_EXPR
9668 || TREE_CODE (arg0) == MINUS_EXPR)
9669 && TREE_CODE (TREE_OPERAND (arg0, 1)) == REAL_CST
9670 && 0 != (tem = const_binop (TREE_CODE (arg0) == PLUS_EXPR
9671 ? MINUS_EXPR : PLUS_EXPR,
9672 arg1, TREE_OPERAND (arg0, 1), 0))
9673 && !TREE_OVERFLOW (tem))
9674 return fold_build2_loc (loc, code, type, TREE_OPERAND (arg0, 0), tem);
9676 /* Likewise, we can simplify a comparison of a real constant with
9677 a MINUS_EXPR whose first operand is also a real constant, i.e.
9678 (c1 - x) < c2 becomes x > c1-c2. Reordering is allowed on
9679 floating-point types only if -fassociative-math is set. */
9680 if (flag_associative_math
9681 && TREE_CODE (arg1) == REAL_CST
9682 && TREE_CODE (arg0) == MINUS_EXPR
9683 && TREE_CODE (TREE_OPERAND (arg0, 0)) == REAL_CST
9684 && 0 != (tem = const_binop (MINUS_EXPR, TREE_OPERAND (arg0, 0),
9686 && !TREE_OVERFLOW (tem))
9687 return fold_build2_loc (loc, swap_tree_comparison (code), type,
9688 TREE_OPERAND (arg0, 1), tem);
9690 /* Fold comparisons against built-in math functions. */
9691 if (TREE_CODE (arg1) == REAL_CST
9692 && flag_unsafe_math_optimizations
9693 && ! flag_errno_math)
9695 enum built_in_function fcode = builtin_mathfn_code (arg0);
9697 if (fcode != END_BUILTINS)
9699 tem = fold_mathfn_compare (loc, fcode, code, type, arg0, arg1);
9700 if (tem != NULL_TREE)
9706 if (TREE_CODE (TREE_TYPE (arg0)) == INTEGER_TYPE
9707 && CONVERT_EXPR_P (arg0))
9709 /* If we are widening one operand of an integer comparison,
9710 see if the other operand is similarly being widened. Perhaps we
9711 can do the comparison in the narrower type. */
9712 tem = fold_widened_comparison (loc, code, type, arg0, arg1);
9716 /* Or if we are changing signedness. */
9717 tem = fold_sign_changed_comparison (loc, code, type, arg0, arg1);
9722 /* If this is comparing a constant with a MIN_EXPR or a MAX_EXPR of a
9723 constant, we can simplify it. */
9724 if (TREE_CODE (arg1) == INTEGER_CST
9725 && (TREE_CODE (arg0) == MIN_EXPR
9726 || TREE_CODE (arg0) == MAX_EXPR)
9727 && TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST)
9729 tem = optimize_minmax_comparison (loc, code, type, op0, op1);
9734 /* Simplify comparison of something with itself. (For IEEE
9735 floating-point, we can only do some of these simplifications.) */
9736 if (operand_equal_p (arg0, arg1, 0))
9741 if (! FLOAT_TYPE_P (TREE_TYPE (arg0))
9742 || ! HONOR_NANS (TYPE_MODE (TREE_TYPE (arg0))))
9743 return constant_boolean_node (1, type);
9748 if (! FLOAT_TYPE_P (TREE_TYPE (arg0))
9749 || ! HONOR_NANS (TYPE_MODE (TREE_TYPE (arg0))))
9750 return constant_boolean_node (1, type);
9751 return fold_build2_loc (loc, EQ_EXPR, type, arg0, arg1);
9754 /* For NE, we can only do this simplification if integer
9755 or we don't honor IEEE floating point NaNs. */
9756 if (FLOAT_TYPE_P (TREE_TYPE (arg0))
9757 && HONOR_NANS (TYPE_MODE (TREE_TYPE (arg0))))
9759 /* ... fall through ... */
9762 return constant_boolean_node (0, type);
9768 /* If we are comparing an expression that just has comparisons
9769 of two integer values, arithmetic expressions of those comparisons,
9770 and constants, we can simplify it. There are only three cases
9771 to check: the two values can either be equal, the first can be
9772 greater, or the second can be greater. Fold the expression for
9773 those three values. Since each value must be 0 or 1, we have
9774 eight possibilities, each of which corresponds to the constant 0
9775 or 1 or one of the six possible comparisons.
9777 This handles common cases like (a > b) == 0 but also handles
9778 expressions like ((x > y) - (y > x)) > 0, which supposedly
9779 occur in macroized code. */
9781 if (TREE_CODE (arg1) == INTEGER_CST && TREE_CODE (arg0) != INTEGER_CST)
9783 tree cval1 = 0, cval2 = 0;
9786 if (twoval_comparison_p (arg0, &cval1, &cval2, &save_p)
9787 /* Don't handle degenerate cases here; they should already
9788 have been handled anyway. */
9789 && cval1 != 0 && cval2 != 0
9790 && ! (TREE_CONSTANT (cval1) && TREE_CONSTANT (cval2))
9791 && TREE_TYPE (cval1) == TREE_TYPE (cval2)
9792 && INTEGRAL_TYPE_P (TREE_TYPE (cval1))
9793 && TYPE_MAX_VALUE (TREE_TYPE (cval1))
9794 && TYPE_MAX_VALUE (TREE_TYPE (cval2))
9795 && ! operand_equal_p (TYPE_MIN_VALUE (TREE_TYPE (cval1)),
9796 TYPE_MAX_VALUE (TREE_TYPE (cval2)), 0))
9798 tree maxval = TYPE_MAX_VALUE (TREE_TYPE (cval1));
9799 tree minval = TYPE_MIN_VALUE (TREE_TYPE (cval1));
9801 /* We can't just pass T to eval_subst in case cval1 or cval2
9802 was the same as ARG1. */
9805 = fold_build2_loc (loc, code, type,
9806 eval_subst (loc, arg0, cval1, maxval,
9810 = fold_build2_loc (loc, code, type,
9811 eval_subst (loc, arg0, cval1, maxval,
9815 = fold_build2_loc (loc, code, type,
9816 eval_subst (loc, arg0, cval1, minval,
9820 /* All three of these results should be 0 or 1. Confirm they are.
9821 Then use those values to select the proper code to use. */
9823 if (TREE_CODE (high_result) == INTEGER_CST
9824 && TREE_CODE (equal_result) == INTEGER_CST
9825 && TREE_CODE (low_result) == INTEGER_CST)
9827 /* Make a 3-bit mask with the high-order bit being the
9828 value for `>', the next for '=', and the low for '<'. */
9829 switch ((integer_onep (high_result) * 4)
9830 + (integer_onep (equal_result) * 2)
9831 + integer_onep (low_result))
9835 return omit_one_operand_loc (loc, type, integer_zero_node, arg0);
9856 return omit_one_operand_loc (loc, type, integer_one_node, arg0);
9861 tem = save_expr (build2 (code, type, cval1, cval2));
9862 SET_EXPR_LOCATION (tem, loc);
9865 return fold_build2_loc (loc, code, type, cval1, cval2);
9870 /* We can fold X/C1 op C2 where C1 and C2 are integer constants
9871 into a single range test. */
9872 if ((TREE_CODE (arg0) == TRUNC_DIV_EXPR
9873 || TREE_CODE (arg0) == EXACT_DIV_EXPR)
9874 && TREE_CODE (arg1) == INTEGER_CST
9875 && TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST
9876 && !integer_zerop (TREE_OPERAND (arg0, 1))
9877 && !TREE_OVERFLOW (TREE_OPERAND (arg0, 1))
9878 && !TREE_OVERFLOW (arg1))
9880 tem = fold_div_compare (loc, code, type, arg0, arg1);
9881 if (tem != NULL_TREE)
9885 /* Fold ~X op ~Y as Y op X. */
9886 if (TREE_CODE (arg0) == BIT_NOT_EXPR
9887 && TREE_CODE (arg1) == BIT_NOT_EXPR)
9889 tree cmp_type = TREE_TYPE (TREE_OPERAND (arg0, 0));
9890 return fold_build2_loc (loc, code, type,
9891 fold_convert_loc (loc, cmp_type,
9892 TREE_OPERAND (arg1, 0)),
9893 TREE_OPERAND (arg0, 0));
9896 /* Fold ~X op C as X op' ~C, where op' is the swapped comparison. */
9897 if (TREE_CODE (arg0) == BIT_NOT_EXPR
9898 && TREE_CODE (arg1) == INTEGER_CST)
9900 tree cmp_type = TREE_TYPE (TREE_OPERAND (arg0, 0));
9901 return fold_build2_loc (loc, swap_tree_comparison (code), type,
9902 TREE_OPERAND (arg0, 0),
9903 fold_build1_loc (loc, BIT_NOT_EXPR, cmp_type,
9904 fold_convert_loc (loc, cmp_type, arg1)));
9911 /* Subroutine of fold_binary. Optimize complex multiplications of the
9912 form z * conj(z), as pow(realpart(z),2) + pow(imagpart(z),2). The
9913 argument EXPR represents the expression "z" of type TYPE. */
9916 fold_mult_zconjz (location_t loc, tree type, tree expr)
9918 tree itype = TREE_TYPE (type);
9919 tree rpart, ipart, tem;
9921 if (TREE_CODE (expr) == COMPLEX_EXPR)
9923 rpart = TREE_OPERAND (expr, 0);
9924 ipart = TREE_OPERAND (expr, 1);
9926 else if (TREE_CODE (expr) == COMPLEX_CST)
9928 rpart = TREE_REALPART (expr);
9929 ipart = TREE_IMAGPART (expr);
9933 expr = save_expr (expr);
9934 rpart = fold_build1_loc (loc, REALPART_EXPR, itype, expr);
9935 ipart = fold_build1_loc (loc, IMAGPART_EXPR, itype, expr);
9938 rpart = save_expr (rpart);
9939 ipart = save_expr (ipart);
9940 tem = fold_build2_loc (loc, PLUS_EXPR, itype,
9941 fold_build2_loc (loc, MULT_EXPR, itype, rpart, rpart),
9942 fold_build2_loc (loc, MULT_EXPR, itype, ipart, ipart));
9943 return fold_build2_loc (loc, COMPLEX_EXPR, type, tem,
9944 fold_convert_loc (loc, itype, integer_zero_node));
9948 /* Subroutine of fold_binary. If P is the value of EXPR, computes
9949 power-of-two M and (arbitrary) N such that M divides (P-N). This condition
9950 guarantees that P and N have the same least significant log2(M) bits.
9951 N is not otherwise constrained. In particular, N is not normalized to
9952 0 <= N < M as is common. In general, the precise value of P is unknown.
9953 M is chosen as large as possible such that constant N can be determined.
9955 Returns M and sets *RESIDUE to N.
9957 If ALLOW_FUNC_ALIGN is true, do take functions' DECL_ALIGN_UNIT into
9958 account. This is not always possible due to PR 35705.
9961 static unsigned HOST_WIDE_INT
9962 get_pointer_modulus_and_residue (tree expr, unsigned HOST_WIDE_INT *residue,
9963 bool allow_func_align)
9965 enum tree_code code;
9969 code = TREE_CODE (expr);
9970 if (code == ADDR_EXPR)
9972 expr = TREE_OPERAND (expr, 0);
9973 if (handled_component_p (expr))
9975 HOST_WIDE_INT bitsize, bitpos;
9977 enum machine_mode mode;
9978 int unsignedp, volatilep;
9980 expr = get_inner_reference (expr, &bitsize, &bitpos, &offset,
9981 &mode, &unsignedp, &volatilep, false);
9982 *residue = bitpos / BITS_PER_UNIT;
9985 if (TREE_CODE (offset) == INTEGER_CST)
9986 *residue += TREE_INT_CST_LOW (offset);
9988 /* We don't handle more complicated offset expressions. */
9994 && (allow_func_align || TREE_CODE (expr) != FUNCTION_DECL))
9995 return DECL_ALIGN_UNIT (expr);
9997 else if (code == POINTER_PLUS_EXPR)
10000 unsigned HOST_WIDE_INT modulus;
10001 enum tree_code inner_code;
10003 op0 = TREE_OPERAND (expr, 0);
10005 modulus = get_pointer_modulus_and_residue (op0, residue,
10008 op1 = TREE_OPERAND (expr, 1);
10010 inner_code = TREE_CODE (op1);
10011 if (inner_code == INTEGER_CST)
10013 *residue += TREE_INT_CST_LOW (op1);
10016 else if (inner_code == MULT_EXPR)
10018 op1 = TREE_OPERAND (op1, 1);
10019 if (TREE_CODE (op1) == INTEGER_CST)
10021 unsigned HOST_WIDE_INT align;
10023 /* Compute the greatest power-of-2 divisor of op1. */
10024 align = TREE_INT_CST_LOW (op1);
10027 /* If align is non-zero and less than *modulus, replace
10028 *modulus with align., If align is 0, then either op1 is 0
10029 or the greatest power-of-2 divisor of op1 doesn't fit in an
10030 unsigned HOST_WIDE_INT. In either case, no additional
10031 constraint is imposed. */
10033 modulus = MIN (modulus, align);
10040 /* If we get here, we were unable to determine anything useful about the
10046 /* Fold a binary expression of code CODE and type TYPE with operands
10047 OP0 and OP1. LOC is the location of the resulting expression.
10048 Return the folded expression if folding is successful. Otherwise,
10049 return NULL_TREE. */
10052 fold_binary_loc (location_t loc,
10053 enum tree_code code, tree type, tree op0, tree op1)
10055 enum tree_code_class kind = TREE_CODE_CLASS (code);
10056 tree arg0, arg1, tem;
10057 tree t1 = NULL_TREE;
10058 bool strict_overflow_p;
10060 gcc_assert (IS_EXPR_CODE_CLASS (kind)
10061 && TREE_CODE_LENGTH (code) == 2
10062 && op0 != NULL_TREE
10063 && op1 != NULL_TREE);
10068 /* Strip any conversions that don't change the mode. This is
10069 safe for every expression, except for a comparison expression
10070 because its signedness is derived from its operands. So, in
10071 the latter case, only strip conversions that don't change the
10072 signedness. MIN_EXPR/MAX_EXPR also need signedness of arguments
10075 Note that this is done as an internal manipulation within the
10076 constant folder, in order to find the simplest representation
10077 of the arguments so that their form can be studied. In any
10078 cases, the appropriate type conversions should be put back in
10079 the tree that will get out of the constant folder. */
10081 if (kind == tcc_comparison || code == MIN_EXPR || code == MAX_EXPR)
10083 STRIP_SIGN_NOPS (arg0);
10084 STRIP_SIGN_NOPS (arg1);
10092 /* Note that TREE_CONSTANT isn't enough: static var addresses are
10093 constant but we can't do arithmetic on them. */
10094 if ((TREE_CODE (arg0) == INTEGER_CST && TREE_CODE (arg1) == INTEGER_CST)
10095 || (TREE_CODE (arg0) == REAL_CST && TREE_CODE (arg1) == REAL_CST)
10096 || (TREE_CODE (arg0) == FIXED_CST && TREE_CODE (arg1) == FIXED_CST)
10097 || (TREE_CODE (arg0) == FIXED_CST && TREE_CODE (arg1) == INTEGER_CST)
10098 || (TREE_CODE (arg0) == COMPLEX_CST && TREE_CODE (arg1) == COMPLEX_CST)
10099 || (TREE_CODE (arg0) == VECTOR_CST && TREE_CODE (arg1) == VECTOR_CST))
10101 if (kind == tcc_binary)
10103 /* Make sure type and arg0 have the same saturating flag. */
10104 gcc_assert (TYPE_SATURATING (type)
10105 == TYPE_SATURATING (TREE_TYPE (arg0)));
10106 tem = const_binop (code, arg0, arg1, 0);
10108 else if (kind == tcc_comparison)
10109 tem = fold_relational_const (code, type, arg0, arg1);
10113 if (tem != NULL_TREE)
10115 if (TREE_TYPE (tem) != type)
10116 tem = fold_convert_loc (loc, type, tem);
10121 /* If this is a commutative operation, and ARG0 is a constant, move it
10122 to ARG1 to reduce the number of tests below. */
10123 if (commutative_tree_code (code)
10124 && tree_swap_operands_p (arg0, arg1, true))
10125 return fold_build2_loc (loc, code, type, op1, op0);
10127 /* ARG0 is the first operand of EXPR, and ARG1 is the second operand.
10129 First check for cases where an arithmetic operation is applied to a
10130 compound, conditional, or comparison operation. Push the arithmetic
10131 operation inside the compound or conditional to see if any folding
10132 can then be done. Convert comparison to conditional for this purpose.
10133 The also optimizes non-constant cases that used to be done in
10136 Before we do that, see if this is a BIT_AND_EXPR or a BIT_IOR_EXPR,
10137 one of the operands is a comparison and the other is a comparison, a
10138 BIT_AND_EXPR with the constant 1, or a truth value. In that case, the
10139 code below would make the expression more complex. Change it to a
10140 TRUTH_{AND,OR}_EXPR. Likewise, convert a similar NE_EXPR to
10141 TRUTH_XOR_EXPR and an EQ_EXPR to the inversion of a TRUTH_XOR_EXPR. */
10143 if ((code == BIT_AND_EXPR || code == BIT_IOR_EXPR
10144 || code == EQ_EXPR || code == NE_EXPR)
10145 && ((truth_value_p (TREE_CODE (arg0))
10146 && (truth_value_p (TREE_CODE (arg1))
10147 || (TREE_CODE (arg1) == BIT_AND_EXPR
10148 && integer_onep (TREE_OPERAND (arg1, 1)))))
10149 || (truth_value_p (TREE_CODE (arg1))
10150 && (truth_value_p (TREE_CODE (arg0))
10151 || (TREE_CODE (arg0) == BIT_AND_EXPR
10152 && integer_onep (TREE_OPERAND (arg0, 1)))))))
10154 tem = fold_build2_loc (loc, code == BIT_AND_EXPR ? TRUTH_AND_EXPR
10155 : code == BIT_IOR_EXPR ? TRUTH_OR_EXPR
10158 fold_convert_loc (loc, boolean_type_node, arg0),
10159 fold_convert_loc (loc, boolean_type_node, arg1));
10161 if (code == EQ_EXPR)
10162 tem = invert_truthvalue_loc (loc, tem);
10164 return fold_convert_loc (loc, type, tem);
10167 if (TREE_CODE_CLASS (code) == tcc_binary
10168 || TREE_CODE_CLASS (code) == tcc_comparison)
10170 if (TREE_CODE (arg0) == COMPOUND_EXPR)
10172 tem = fold_build2_loc (loc, code, type,
10173 fold_convert_loc (loc, TREE_TYPE (op0),
10174 TREE_OPERAND (arg0, 1)), op1);
10175 tem = build2 (COMPOUND_EXPR, type, TREE_OPERAND (arg0, 0), tem);
10176 goto fold_binary_exit;
10178 if (TREE_CODE (arg1) == COMPOUND_EXPR
10179 && reorder_operands_p (arg0, TREE_OPERAND (arg1, 0)))
10181 tem = fold_build2_loc (loc, code, type, op0,
10182 fold_convert_loc (loc, TREE_TYPE (op1),
10183 TREE_OPERAND (arg1, 1)));
10184 tem = build2 (COMPOUND_EXPR, type, TREE_OPERAND (arg1, 0), tem);
10185 goto fold_binary_exit;
10188 if (TREE_CODE (arg0) == COND_EXPR || COMPARISON_CLASS_P (arg0))
10190 tem = fold_binary_op_with_conditional_arg (loc, code, type, op0, op1,
10192 /*cond_first_p=*/1);
10193 if (tem != NULL_TREE)
10197 if (TREE_CODE (arg1) == COND_EXPR || COMPARISON_CLASS_P (arg1))
10199 tem = fold_binary_op_with_conditional_arg (loc, code, type, op0, op1,
10201 /*cond_first_p=*/0);
10202 if (tem != NULL_TREE)
10209 case POINTER_PLUS_EXPR:
10210 /* 0 +p index -> (type)index */
10211 if (integer_zerop (arg0))
10212 return non_lvalue_loc (loc, fold_convert_loc (loc, type, arg1));
10214 /* PTR +p 0 -> PTR */
10215 if (integer_zerop (arg1))
10216 return non_lvalue_loc (loc, fold_convert_loc (loc, type, arg0));
10218 /* INT +p INT -> (PTR)(INT + INT). Stripping types allows for this. */
10219 if (INTEGRAL_TYPE_P (TREE_TYPE (arg1))
10220 && INTEGRAL_TYPE_P (TREE_TYPE (arg0)))
10221 return fold_convert_loc (loc, type,
10222 fold_build2_loc (loc, PLUS_EXPR, sizetype,
10223 fold_convert_loc (loc, sizetype,
10225 fold_convert_loc (loc, sizetype,
10228 /* index +p PTR -> PTR +p index */
10229 if (POINTER_TYPE_P (TREE_TYPE (arg1))
10230 && INTEGRAL_TYPE_P (TREE_TYPE (arg0)))
10231 return fold_build2_loc (loc, POINTER_PLUS_EXPR, type,
10232 fold_convert_loc (loc, type, arg1),
10233 fold_convert_loc (loc, sizetype, arg0));
10235 /* (PTR +p B) +p A -> PTR +p (B + A) */
10236 if (TREE_CODE (arg0) == POINTER_PLUS_EXPR)
10239 tree arg01 = fold_convert_loc (loc, sizetype, TREE_OPERAND (arg0, 1));
10240 tree arg00 = TREE_OPERAND (arg0, 0);
10241 inner = fold_build2_loc (loc, PLUS_EXPR, sizetype,
10242 arg01, fold_convert_loc (loc, sizetype, arg1));
10243 return fold_convert_loc (loc, type,
10244 fold_build2_loc (loc, POINTER_PLUS_EXPR,
10249 /* PTR_CST +p CST -> CST1 */
10250 if (TREE_CODE (arg0) == INTEGER_CST && TREE_CODE (arg1) == INTEGER_CST)
10251 return fold_build2_loc (loc, PLUS_EXPR, type, arg0,
10252 fold_convert_loc (loc, type, arg1));
10254 /* Try replacing &a[i1] +p c * i2 with &a[i1 + i2], if c is step
10255 of the array. Loop optimizer sometimes produce this type of
10257 if (TREE_CODE (arg0) == ADDR_EXPR)
10259 tem = try_move_mult_to_index (loc, arg0,
10260 fold_convert_loc (loc, sizetype, arg1));
10262 return fold_convert_loc (loc, type, tem);
10268 /* A + (-B) -> A - B */
10269 if (TREE_CODE (arg1) == NEGATE_EXPR)
10270 return fold_build2_loc (loc, MINUS_EXPR, type,
10271 fold_convert_loc (loc, type, arg0),
10272 fold_convert_loc (loc, type,
10273 TREE_OPERAND (arg1, 0)));
10274 /* (-A) + B -> B - A */
10275 if (TREE_CODE (arg0) == NEGATE_EXPR
10276 && reorder_operands_p (TREE_OPERAND (arg0, 0), arg1))
10277 return fold_build2_loc (loc, MINUS_EXPR, type,
10278 fold_convert_loc (loc, type, arg1),
10279 fold_convert_loc (loc, type,
10280 TREE_OPERAND (arg0, 0)));
10282 if (INTEGRAL_TYPE_P (type))
10284 /* Convert ~A + 1 to -A. */
10285 if (TREE_CODE (arg0) == BIT_NOT_EXPR
10286 && integer_onep (arg1))
10287 return fold_build1_loc (loc, NEGATE_EXPR, type,
10288 fold_convert_loc (loc, type,
10289 TREE_OPERAND (arg0, 0)));
10291 /* ~X + X is -1. */
10292 if (TREE_CODE (arg0) == BIT_NOT_EXPR
10293 && !TYPE_OVERFLOW_TRAPS (type))
10295 tree tem = TREE_OPERAND (arg0, 0);
10298 if (operand_equal_p (tem, arg1, 0))
10300 t1 = build_int_cst_type (type, -1);
10301 return omit_one_operand_loc (loc, type, t1, arg1);
10305 /* X + ~X is -1. */
10306 if (TREE_CODE (arg1) == BIT_NOT_EXPR
10307 && !TYPE_OVERFLOW_TRAPS (type))
10309 tree tem = TREE_OPERAND (arg1, 0);
10312 if (operand_equal_p (arg0, tem, 0))
10314 t1 = build_int_cst_type (type, -1);
10315 return omit_one_operand_loc (loc, type, t1, arg0);
10319 /* X + (X / CST) * -CST is X % CST. */
10320 if (TREE_CODE (arg1) == MULT_EXPR
10321 && TREE_CODE (TREE_OPERAND (arg1, 0)) == TRUNC_DIV_EXPR
10322 && operand_equal_p (arg0,
10323 TREE_OPERAND (TREE_OPERAND (arg1, 0), 0), 0))
10325 tree cst0 = TREE_OPERAND (TREE_OPERAND (arg1, 0), 1);
10326 tree cst1 = TREE_OPERAND (arg1, 1);
10327 tree sum = fold_binary_loc (loc, PLUS_EXPR, TREE_TYPE (cst1),
10329 if (sum && integer_zerop (sum))
10330 return fold_convert_loc (loc, type,
10331 fold_build2_loc (loc, TRUNC_MOD_EXPR,
10332 TREE_TYPE (arg0), arg0,
10337 /* Handle (A1 * C1) + (A2 * C2) with A1, A2 or C1, C2 being the
10338 same or one. Make sure type is not saturating.
10339 fold_plusminus_mult_expr will re-associate. */
10340 if ((TREE_CODE (arg0) == MULT_EXPR
10341 || TREE_CODE (arg1) == MULT_EXPR)
10342 && !TYPE_SATURATING (type)
10343 && (!FLOAT_TYPE_P (type) || flag_associative_math))
10345 tree tem = fold_plusminus_mult_expr (loc, code, type, arg0, arg1);
10350 if (! FLOAT_TYPE_P (type))
10352 if (integer_zerop (arg1))
10353 return non_lvalue_loc (loc, fold_convert_loc (loc, type, arg0));
10355 /* If we are adding two BIT_AND_EXPR's, both of which are and'ing
10356 with a constant, and the two constants have no bits in common,
10357 we should treat this as a BIT_IOR_EXPR since this may produce more
10358 simplifications. */
10359 if (TREE_CODE (arg0) == BIT_AND_EXPR
10360 && TREE_CODE (arg1) == BIT_AND_EXPR
10361 && TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST
10362 && TREE_CODE (TREE_OPERAND (arg1, 1)) == INTEGER_CST
10363 && integer_zerop (const_binop (BIT_AND_EXPR,
10364 TREE_OPERAND (arg0, 1),
10365 TREE_OPERAND (arg1, 1), 0)))
10367 code = BIT_IOR_EXPR;
10371 /* Reassociate (plus (plus (mult) (foo)) (mult)) as
10372 (plus (plus (mult) (mult)) (foo)) so that we can
10373 take advantage of the factoring cases below. */
10374 if (((TREE_CODE (arg0) == PLUS_EXPR
10375 || TREE_CODE (arg0) == MINUS_EXPR)
10376 && TREE_CODE (arg1) == MULT_EXPR)
10377 || ((TREE_CODE (arg1) == PLUS_EXPR
10378 || TREE_CODE (arg1) == MINUS_EXPR)
10379 && TREE_CODE (arg0) == MULT_EXPR))
10381 tree parg0, parg1, parg, marg;
10382 enum tree_code pcode;
10384 if (TREE_CODE (arg1) == MULT_EXPR)
10385 parg = arg0, marg = arg1;
10387 parg = arg1, marg = arg0;
10388 pcode = TREE_CODE (parg);
10389 parg0 = TREE_OPERAND (parg, 0);
10390 parg1 = TREE_OPERAND (parg, 1);
10391 STRIP_NOPS (parg0);
10392 STRIP_NOPS (parg1);
10394 if (TREE_CODE (parg0) == MULT_EXPR
10395 && TREE_CODE (parg1) != MULT_EXPR)
10396 return fold_build2_loc (loc, pcode, type,
10397 fold_build2_loc (loc, PLUS_EXPR, type,
10398 fold_convert_loc (loc, type,
10400 fold_convert_loc (loc, type,
10402 fold_convert_loc (loc, type, parg1));
10403 if (TREE_CODE (parg0) != MULT_EXPR
10404 && TREE_CODE (parg1) == MULT_EXPR)
10406 fold_build2_loc (loc, PLUS_EXPR, type,
10407 fold_convert_loc (loc, type, parg0),
10408 fold_build2_loc (loc, pcode, type,
10409 fold_convert_loc (loc, type, marg),
10410 fold_convert_loc (loc, type,
10416 /* See if ARG1 is zero and X + ARG1 reduces to X. */
10417 if (fold_real_zero_addition_p (TREE_TYPE (arg0), arg1, 0))
10418 return non_lvalue_loc (loc, fold_convert_loc (loc, type, arg0));
10420 /* Likewise if the operands are reversed. */
10421 if (fold_real_zero_addition_p (TREE_TYPE (arg1), arg0, 0))
10422 return non_lvalue_loc (loc, fold_convert_loc (loc, type, arg1));
10424 /* Convert X + -C into X - C. */
10425 if (TREE_CODE (arg1) == REAL_CST
10426 && REAL_VALUE_NEGATIVE (TREE_REAL_CST (arg1)))
10428 tem = fold_negate_const (arg1, type);
10429 if (!TREE_OVERFLOW (arg1) || !flag_trapping_math)
10430 return fold_build2_loc (loc, MINUS_EXPR, type,
10431 fold_convert_loc (loc, type, arg0),
10432 fold_convert_loc (loc, type, tem));
10435 /* Fold __complex__ ( x, 0 ) + __complex__ ( 0, y )
10436 to __complex__ ( x, y ). This is not the same for SNaNs or
10437 if signed zeros are involved. */
10438 if (!HONOR_SNANS (TYPE_MODE (TREE_TYPE (arg0)))
10439 && !HONOR_SIGNED_ZEROS (TYPE_MODE (TREE_TYPE (arg0)))
10440 && COMPLEX_FLOAT_TYPE_P (TREE_TYPE (arg0)))
10442 tree rtype = TREE_TYPE (TREE_TYPE (arg0));
10443 tree arg0r = fold_unary_loc (loc, REALPART_EXPR, rtype, arg0);
10444 tree arg0i = fold_unary_loc (loc, IMAGPART_EXPR, rtype, arg0);
10445 bool arg0rz = false, arg0iz = false;
10446 if ((arg0r && (arg0rz = real_zerop (arg0r)))
10447 || (arg0i && (arg0iz = real_zerop (arg0i))))
10449 tree arg1r = fold_unary_loc (loc, REALPART_EXPR, rtype, arg1);
10450 tree arg1i = fold_unary_loc (loc, IMAGPART_EXPR, rtype, arg1);
10451 if (arg0rz && arg1i && real_zerop (arg1i))
10453 tree rp = arg1r ? arg1r
10454 : build1 (REALPART_EXPR, rtype, arg1);
10455 tree ip = arg0i ? arg0i
10456 : build1 (IMAGPART_EXPR, rtype, arg0);
10457 return fold_build2_loc (loc, COMPLEX_EXPR, type, rp, ip);
10459 else if (arg0iz && arg1r && real_zerop (arg1r))
10461 tree rp = arg0r ? arg0r
10462 : build1 (REALPART_EXPR, rtype, arg0);
10463 tree ip = arg1i ? arg1i
10464 : build1 (IMAGPART_EXPR, rtype, arg1);
10465 return fold_build2_loc (loc, COMPLEX_EXPR, type, rp, ip);
10470 if (flag_unsafe_math_optimizations
10471 && (TREE_CODE (arg0) == RDIV_EXPR || TREE_CODE (arg0) == MULT_EXPR)
10472 && (TREE_CODE (arg1) == RDIV_EXPR || TREE_CODE (arg1) == MULT_EXPR)
10473 && (tem = distribute_real_division (loc, code, type, arg0, arg1)))
10476 /* Convert x+x into x*2.0. */
10477 if (operand_equal_p (arg0, arg1, 0)
10478 && SCALAR_FLOAT_TYPE_P (type))
10479 return fold_build2_loc (loc, MULT_EXPR, type, arg0,
10480 build_real (type, dconst2));
10482 /* Convert a + (b*c + d*e) into (a + b*c) + d*e.
10483 We associate floats only if the user has specified
10484 -fassociative-math. */
10485 if (flag_associative_math
10486 && TREE_CODE (arg1) == PLUS_EXPR
10487 && TREE_CODE (arg0) != MULT_EXPR)
10489 tree tree10 = TREE_OPERAND (arg1, 0);
10490 tree tree11 = TREE_OPERAND (arg1, 1);
10491 if (TREE_CODE (tree11) == MULT_EXPR
10492 && TREE_CODE (tree10) == MULT_EXPR)
10495 tree0 = fold_build2_loc (loc, PLUS_EXPR, type, arg0, tree10);
10496 return fold_build2_loc (loc, PLUS_EXPR, type, tree0, tree11);
10499 /* Convert (b*c + d*e) + a into b*c + (d*e +a).
10500 We associate floats only if the user has specified
10501 -fassociative-math. */
10502 if (flag_associative_math
10503 && TREE_CODE (arg0) == PLUS_EXPR
10504 && TREE_CODE (arg1) != MULT_EXPR)
10506 tree tree00 = TREE_OPERAND (arg0, 0);
10507 tree tree01 = TREE_OPERAND (arg0, 1);
10508 if (TREE_CODE (tree01) == MULT_EXPR
10509 && TREE_CODE (tree00) == MULT_EXPR)
10512 tree0 = fold_build2_loc (loc, PLUS_EXPR, type, tree01, arg1);
10513 return fold_build2_loc (loc, PLUS_EXPR, type, tree00, tree0);
10519 /* (A << C1) + (A >> C2) if A is unsigned and C1+C2 is the size of A
10520 is a rotate of A by C1 bits. */
10521 /* (A << B) + (A >> (Z - B)) if A is unsigned and Z is the size of A
10522 is a rotate of A by B bits. */
10524 enum tree_code code0, code1;
10526 code0 = TREE_CODE (arg0);
10527 code1 = TREE_CODE (arg1);
10528 if (((code0 == RSHIFT_EXPR && code1 == LSHIFT_EXPR)
10529 || (code1 == RSHIFT_EXPR && code0 == LSHIFT_EXPR))
10530 && operand_equal_p (TREE_OPERAND (arg0, 0),
10531 TREE_OPERAND (arg1, 0), 0)
10532 && (rtype = TREE_TYPE (TREE_OPERAND (arg0, 0)),
10533 TYPE_UNSIGNED (rtype))
10534 /* Only create rotates in complete modes. Other cases are not
10535 expanded properly. */
10536 && TYPE_PRECISION (rtype) == GET_MODE_PRECISION (TYPE_MODE (rtype)))
10538 tree tree01, tree11;
10539 enum tree_code code01, code11;
10541 tree01 = TREE_OPERAND (arg0, 1);
10542 tree11 = TREE_OPERAND (arg1, 1);
10543 STRIP_NOPS (tree01);
10544 STRIP_NOPS (tree11);
10545 code01 = TREE_CODE (tree01);
10546 code11 = TREE_CODE (tree11);
10547 if (code01 == INTEGER_CST
10548 && code11 == INTEGER_CST
10549 && TREE_INT_CST_HIGH (tree01) == 0
10550 && TREE_INT_CST_HIGH (tree11) == 0
10551 && ((TREE_INT_CST_LOW (tree01) + TREE_INT_CST_LOW (tree11))
10552 == TYPE_PRECISION (TREE_TYPE (TREE_OPERAND (arg0, 0)))))
10554 tem = build2 (LROTATE_EXPR,
10555 TREE_TYPE (TREE_OPERAND (arg0, 0)),
10556 TREE_OPERAND (arg0, 0),
10557 code0 == LSHIFT_EXPR
10558 ? tree01 : tree11);
10559 SET_EXPR_LOCATION (tem, loc);
10560 return fold_convert_loc (loc, type, tem);
10562 else if (code11 == MINUS_EXPR)
10564 tree tree110, tree111;
10565 tree110 = TREE_OPERAND (tree11, 0);
10566 tree111 = TREE_OPERAND (tree11, 1);
10567 STRIP_NOPS (tree110);
10568 STRIP_NOPS (tree111);
10569 if (TREE_CODE (tree110) == INTEGER_CST
10570 && 0 == compare_tree_int (tree110,
10572 (TREE_TYPE (TREE_OPERAND
10574 && operand_equal_p (tree01, tree111, 0))
10576 fold_convert_loc (loc, type,
10577 build2 ((code0 == LSHIFT_EXPR
10580 TREE_TYPE (TREE_OPERAND (arg0, 0)),
10581 TREE_OPERAND (arg0, 0), tree01));
10583 else if (code01 == MINUS_EXPR)
10585 tree tree010, tree011;
10586 tree010 = TREE_OPERAND (tree01, 0);
10587 tree011 = TREE_OPERAND (tree01, 1);
10588 STRIP_NOPS (tree010);
10589 STRIP_NOPS (tree011);
10590 if (TREE_CODE (tree010) == INTEGER_CST
10591 && 0 == compare_tree_int (tree010,
10593 (TREE_TYPE (TREE_OPERAND
10595 && operand_equal_p (tree11, tree011, 0))
10596 return fold_convert_loc
10598 build2 ((code0 != LSHIFT_EXPR
10601 TREE_TYPE (TREE_OPERAND (arg0, 0)),
10602 TREE_OPERAND (arg0, 0), tree11));
10608 /* In most languages, can't associate operations on floats through
10609 parentheses. Rather than remember where the parentheses were, we
10610 don't associate floats at all, unless the user has specified
10611 -fassociative-math.
10612 And, we need to make sure type is not saturating. */
10614 if ((! FLOAT_TYPE_P (type) || flag_associative_math)
10615 && !TYPE_SATURATING (type))
10617 tree var0, con0, lit0, minus_lit0;
10618 tree var1, con1, lit1, minus_lit1;
10621 /* Split both trees into variables, constants, and literals. Then
10622 associate each group together, the constants with literals,
10623 then the result with variables. This increases the chances of
10624 literals being recombined later and of generating relocatable
10625 expressions for the sum of a constant and literal. */
10626 var0 = split_tree (arg0, code, &con0, &lit0, &minus_lit0, 0);
10627 var1 = split_tree (arg1, code, &con1, &lit1, &minus_lit1,
10628 code == MINUS_EXPR);
10630 /* With undefined overflow we can only associate constants
10631 with one variable. */
10632 if (((POINTER_TYPE_P (type) && POINTER_TYPE_OVERFLOW_UNDEFINED)
10633 || (INTEGRAL_TYPE_P (type) && !TYPE_OVERFLOW_WRAPS (type)))
10639 if (TREE_CODE (tmp0) == NEGATE_EXPR)
10640 tmp0 = TREE_OPERAND (tmp0, 0);
10641 if (TREE_CODE (tmp1) == NEGATE_EXPR)
10642 tmp1 = TREE_OPERAND (tmp1, 0);
10643 /* The only case we can still associate with two variables
10644 is if they are the same, modulo negation. */
10645 if (!operand_equal_p (tmp0, tmp1, 0))
10649 /* Only do something if we found more than two objects. Otherwise,
10650 nothing has changed and we risk infinite recursion. */
10652 && (2 < ((var0 != 0) + (var1 != 0)
10653 + (con0 != 0) + (con1 != 0)
10654 + (lit0 != 0) + (lit1 != 0)
10655 + (minus_lit0 != 0) + (minus_lit1 != 0))))
10657 /* Recombine MINUS_EXPR operands by using PLUS_EXPR. */
10658 if (code == MINUS_EXPR)
10661 var0 = associate_trees (loc, var0, var1, code, type);
10662 con0 = associate_trees (loc, con0, con1, code, type);
10663 lit0 = associate_trees (loc, lit0, lit1, code, type);
10664 minus_lit0 = associate_trees (loc, minus_lit0, minus_lit1, code, type);
10666 /* Preserve the MINUS_EXPR if the negative part of the literal is
10667 greater than the positive part. Otherwise, the multiplicative
10668 folding code (i.e extract_muldiv) may be fooled in case
10669 unsigned constants are subtracted, like in the following
10670 example: ((X*2 + 4) - 8U)/2. */
10671 if (minus_lit0 && lit0)
10673 if (TREE_CODE (lit0) == INTEGER_CST
10674 && TREE_CODE (minus_lit0) == INTEGER_CST
10675 && tree_int_cst_lt (lit0, minus_lit0))
10677 minus_lit0 = associate_trees (loc, minus_lit0, lit0,
10683 lit0 = associate_trees (loc, lit0, minus_lit0,
10692 fold_convert_loc (loc, type,
10693 associate_trees (loc, var0, minus_lit0,
10694 MINUS_EXPR, type));
10697 con0 = associate_trees (loc, con0, minus_lit0,
10700 fold_convert_loc (loc, type,
10701 associate_trees (loc, var0, con0,
10706 con0 = associate_trees (loc, con0, lit0, code, type);
10708 fold_convert_loc (loc, type, associate_trees (loc, var0, con0,
10716 /* Pointer simplifications for subtraction, simple reassociations. */
10717 if (POINTER_TYPE_P (TREE_TYPE (arg1)) && POINTER_TYPE_P (TREE_TYPE (arg0)))
10719 /* (PTR0 p+ A) - (PTR1 p+ B) -> (PTR0 - PTR1) + (A - B) */
10720 if (TREE_CODE (arg0) == POINTER_PLUS_EXPR
10721 && TREE_CODE (arg1) == POINTER_PLUS_EXPR)
10723 tree arg00 = fold_convert_loc (loc, type, TREE_OPERAND (arg0, 0));
10724 tree arg01 = fold_convert_loc (loc, type, TREE_OPERAND (arg0, 1));
10725 tree arg10 = fold_convert_loc (loc, type, TREE_OPERAND (arg1, 0));
10726 tree arg11 = fold_convert_loc (loc, type, TREE_OPERAND (arg1, 1));
10727 return fold_build2_loc (loc, PLUS_EXPR, type,
10728 fold_build2_loc (loc, MINUS_EXPR, type,
10730 fold_build2_loc (loc, MINUS_EXPR, type,
10733 /* (PTR0 p+ A) - PTR1 -> (PTR0 - PTR1) + A, assuming PTR0 - PTR1 simplifies. */
10734 else if (TREE_CODE (arg0) == POINTER_PLUS_EXPR)
10736 tree arg00 = fold_convert_loc (loc, type, TREE_OPERAND (arg0, 0));
10737 tree arg01 = fold_convert_loc (loc, type, TREE_OPERAND (arg0, 1));
10738 tree tmp = fold_binary_loc (loc, MINUS_EXPR, type, arg00,
10739 fold_convert_loc (loc, type, arg1));
10741 return fold_build2_loc (loc, PLUS_EXPR, type, tmp, arg01);
10744 /* A - (-B) -> A + B */
10745 if (TREE_CODE (arg1) == NEGATE_EXPR)
10746 return fold_build2_loc (loc, PLUS_EXPR, type, op0,
10747 fold_convert_loc (loc, type,
10748 TREE_OPERAND (arg1, 0)));
10749 /* (-A) - B -> (-B) - A where B is easily negated and we can swap. */
10750 if (TREE_CODE (arg0) == NEGATE_EXPR
10751 && (FLOAT_TYPE_P (type)
10752 || INTEGRAL_TYPE_P (type))
10753 && negate_expr_p (arg1)
10754 && reorder_operands_p (arg0, arg1))
10755 return fold_build2_loc (loc, MINUS_EXPR, type,
10756 fold_convert_loc (loc, type,
10757 negate_expr (arg1)),
10758 fold_convert_loc (loc, type,
10759 TREE_OPERAND (arg0, 0)));
10760 /* Convert -A - 1 to ~A. */
10761 if (INTEGRAL_TYPE_P (type)
10762 && TREE_CODE (arg0) == NEGATE_EXPR
10763 && integer_onep (arg1)
10764 && !TYPE_OVERFLOW_TRAPS (type))
10765 return fold_build1_loc (loc, BIT_NOT_EXPR, type,
10766 fold_convert_loc (loc, type,
10767 TREE_OPERAND (arg0, 0)));
10769 /* Convert -1 - A to ~A. */
10770 if (INTEGRAL_TYPE_P (type)
10771 && integer_all_onesp (arg0))
10772 return fold_build1_loc (loc, BIT_NOT_EXPR, type, op1);
10775 /* X - (X / CST) * CST is X % CST. */
10776 if (INTEGRAL_TYPE_P (type)
10777 && TREE_CODE (arg1) == MULT_EXPR
10778 && TREE_CODE (TREE_OPERAND (arg1, 0)) == TRUNC_DIV_EXPR
10779 && operand_equal_p (arg0,
10780 TREE_OPERAND (TREE_OPERAND (arg1, 0), 0), 0)
10781 && operand_equal_p (TREE_OPERAND (TREE_OPERAND (arg1, 0), 1),
10782 TREE_OPERAND (arg1, 1), 0))
10784 fold_convert_loc (loc, type,
10785 fold_build2_loc (loc, TRUNC_MOD_EXPR, TREE_TYPE (arg0),
10786 arg0, TREE_OPERAND (arg1, 1)));
10788 if (! FLOAT_TYPE_P (type))
10790 if (integer_zerop (arg0))
10791 return negate_expr (fold_convert_loc (loc, type, arg1));
10792 if (integer_zerop (arg1))
10793 return non_lvalue_loc (loc, fold_convert_loc (loc, type, arg0));
10795 /* Fold A - (A & B) into ~B & A. */
10796 if (!TREE_SIDE_EFFECTS (arg0)
10797 && TREE_CODE (arg1) == BIT_AND_EXPR)
10799 if (operand_equal_p (arg0, TREE_OPERAND (arg1, 1), 0))
10801 tree arg10 = fold_convert_loc (loc, type,
10802 TREE_OPERAND (arg1, 0));
10803 return fold_build2_loc (loc, BIT_AND_EXPR, type,
10804 fold_build1_loc (loc, BIT_NOT_EXPR,
10806 fold_convert_loc (loc, type, arg0));
10808 if (operand_equal_p (arg0, TREE_OPERAND (arg1, 0), 0))
10810 tree arg11 = fold_convert_loc (loc,
10811 type, TREE_OPERAND (arg1, 1));
10812 return fold_build2_loc (loc, BIT_AND_EXPR, type,
10813 fold_build1_loc (loc, BIT_NOT_EXPR,
10815 fold_convert_loc (loc, type, arg0));
10819 /* Fold (A & ~B) - (A & B) into (A ^ B) - B, where B is
10820 any power of 2 minus 1. */
10821 if (TREE_CODE (arg0) == BIT_AND_EXPR
10822 && TREE_CODE (arg1) == BIT_AND_EXPR
10823 && operand_equal_p (TREE_OPERAND (arg0, 0),
10824 TREE_OPERAND (arg1, 0), 0))
10826 tree mask0 = TREE_OPERAND (arg0, 1);
10827 tree mask1 = TREE_OPERAND (arg1, 1);
10828 tree tem = fold_build1_loc (loc, BIT_NOT_EXPR, type, mask0);
10830 if (operand_equal_p (tem, mask1, 0))
10832 tem = fold_build2_loc (loc, BIT_XOR_EXPR, type,
10833 TREE_OPERAND (arg0, 0), mask1);
10834 return fold_build2_loc (loc, MINUS_EXPR, type, tem, mask1);
10839 /* See if ARG1 is zero and X - ARG1 reduces to X. */
10840 else if (fold_real_zero_addition_p (TREE_TYPE (arg0), arg1, 1))
10841 return non_lvalue_loc (loc, fold_convert_loc (loc, type, arg0));
10843 /* (ARG0 - ARG1) is the same as (-ARG1 + ARG0). So check whether
10844 ARG0 is zero and X + ARG0 reduces to X, since that would mean
10845 (-ARG1 + ARG0) reduces to -ARG1. */
10846 else if (fold_real_zero_addition_p (TREE_TYPE (arg1), arg0, 0))
10847 return negate_expr (fold_convert_loc (loc, type, arg1));
10849 /* Fold __complex__ ( x, 0 ) - __complex__ ( 0, y ) to
10850 __complex__ ( x, -y ). This is not the same for SNaNs or if
10851 signed zeros are involved. */
10852 if (!HONOR_SNANS (TYPE_MODE (TREE_TYPE (arg0)))
10853 && !HONOR_SIGNED_ZEROS (TYPE_MODE (TREE_TYPE (arg0)))
10854 && COMPLEX_FLOAT_TYPE_P (TREE_TYPE (arg0)))
10856 tree rtype = TREE_TYPE (TREE_TYPE (arg0));
10857 tree arg0r = fold_unary_loc (loc, REALPART_EXPR, rtype, arg0);
10858 tree arg0i = fold_unary_loc (loc, IMAGPART_EXPR, rtype, arg0);
10859 bool arg0rz = false, arg0iz = false;
10860 if ((arg0r && (arg0rz = real_zerop (arg0r)))
10861 || (arg0i && (arg0iz = real_zerop (arg0i))))
10863 tree arg1r = fold_unary_loc (loc, REALPART_EXPR, rtype, arg1);
10864 tree arg1i = fold_unary_loc (loc, IMAGPART_EXPR, rtype, arg1);
10865 if (arg0rz && arg1i && real_zerop (arg1i))
10867 tree rp = fold_build1_loc (loc, NEGATE_EXPR, rtype,
10869 : build1 (REALPART_EXPR, rtype, arg1));
10870 tree ip = arg0i ? arg0i
10871 : build1 (IMAGPART_EXPR, rtype, arg0);
10872 return fold_build2_loc (loc, COMPLEX_EXPR, type, rp, ip);
10874 else if (arg0iz && arg1r && real_zerop (arg1r))
10876 tree rp = arg0r ? arg0r
10877 : build1 (REALPART_EXPR, rtype, arg0);
10878 tree ip = fold_build1_loc (loc, NEGATE_EXPR, rtype,
10880 : build1 (IMAGPART_EXPR, rtype, arg1));
10881 return fold_build2_loc (loc, COMPLEX_EXPR, type, rp, ip);
10886 /* Fold &x - &x. This can happen from &x.foo - &x.
10887 This is unsafe for certain floats even in non-IEEE formats.
10888 In IEEE, it is unsafe because it does wrong for NaNs.
10889 Also note that operand_equal_p is always false if an operand
10892 if ((!FLOAT_TYPE_P (type) || !HONOR_NANS (TYPE_MODE (type)))
10893 && operand_equal_p (arg0, arg1, 0))
10894 return fold_convert_loc (loc, type, integer_zero_node);
10896 /* A - B -> A + (-B) if B is easily negatable. */
10897 if (negate_expr_p (arg1)
10898 && ((FLOAT_TYPE_P (type)
10899 /* Avoid this transformation if B is a positive REAL_CST. */
10900 && (TREE_CODE (arg1) != REAL_CST
10901 || REAL_VALUE_NEGATIVE (TREE_REAL_CST (arg1))))
10902 || INTEGRAL_TYPE_P (type)))
10903 return fold_build2_loc (loc, PLUS_EXPR, type,
10904 fold_convert_loc (loc, type, arg0),
10905 fold_convert_loc (loc, type,
10906 negate_expr (arg1)));
10908 /* Try folding difference of addresses. */
10910 HOST_WIDE_INT diff;
10912 if ((TREE_CODE (arg0) == ADDR_EXPR
10913 || TREE_CODE (arg1) == ADDR_EXPR)
10914 && ptr_difference_const (arg0, arg1, &diff))
10915 return build_int_cst_type (type, diff);
10918 /* Fold &a[i] - &a[j] to i-j. */
10919 if (TREE_CODE (arg0) == ADDR_EXPR
10920 && TREE_CODE (TREE_OPERAND (arg0, 0)) == ARRAY_REF
10921 && TREE_CODE (arg1) == ADDR_EXPR
10922 && TREE_CODE (TREE_OPERAND (arg1, 0)) == ARRAY_REF)
10924 tree aref0 = TREE_OPERAND (arg0, 0);
10925 tree aref1 = TREE_OPERAND (arg1, 0);
10926 if (operand_equal_p (TREE_OPERAND (aref0, 0),
10927 TREE_OPERAND (aref1, 0), 0))
10929 tree op0 = fold_convert_loc (loc, type, TREE_OPERAND (aref0, 1));
10930 tree op1 = fold_convert_loc (loc, type, TREE_OPERAND (aref1, 1));
10931 tree esz = array_ref_element_size (aref0);
10932 tree diff = build2 (MINUS_EXPR, type, op0, op1);
10933 return fold_build2_loc (loc, MULT_EXPR, type, diff,
10934 fold_convert_loc (loc, type, esz));
10939 if (FLOAT_TYPE_P (type)
10940 && flag_unsafe_math_optimizations
10941 && (TREE_CODE (arg0) == RDIV_EXPR || TREE_CODE (arg0) == MULT_EXPR)
10942 && (TREE_CODE (arg1) == RDIV_EXPR || TREE_CODE (arg1) == MULT_EXPR)
10943 && (tem = distribute_real_division (loc, code, type, arg0, arg1)))
10946 /* Handle (A1 * C1) - (A2 * C2) with A1, A2 or C1, C2 being the
10947 same or one. Make sure type is not saturating.
10948 fold_plusminus_mult_expr will re-associate. */
10949 if ((TREE_CODE (arg0) == MULT_EXPR
10950 || TREE_CODE (arg1) == MULT_EXPR)
10951 && !TYPE_SATURATING (type)
10952 && (!FLOAT_TYPE_P (type) || flag_associative_math))
10954 tree tem = fold_plusminus_mult_expr (loc, code, type, arg0, arg1);
10962 /* (-A) * (-B) -> A * B */
10963 if (TREE_CODE (arg0) == NEGATE_EXPR && negate_expr_p (arg1))
10964 return fold_build2_loc (loc, MULT_EXPR, type,
10965 fold_convert_loc (loc, type,
10966 TREE_OPERAND (arg0, 0)),
10967 fold_convert_loc (loc, type,
10968 negate_expr (arg1)));
10969 if (TREE_CODE (arg1) == NEGATE_EXPR && negate_expr_p (arg0))
10970 return fold_build2_loc (loc, MULT_EXPR, type,
10971 fold_convert_loc (loc, type,
10972 negate_expr (arg0)),
10973 fold_convert_loc (loc, type,
10974 TREE_OPERAND (arg1, 0)));
10976 if (! FLOAT_TYPE_P (type))
10978 if (integer_zerop (arg1))
10979 return omit_one_operand_loc (loc, type, arg1, arg0);
10980 if (integer_onep (arg1))
10981 return non_lvalue_loc (loc, fold_convert_loc (loc, type, arg0));
10982 /* Transform x * -1 into -x. Make sure to do the negation
10983 on the original operand with conversions not stripped
10984 because we can only strip non-sign-changing conversions. */
10985 if (integer_all_onesp (arg1))
10986 return fold_convert_loc (loc, type, negate_expr (op0));
10987 /* Transform x * -C into -x * C if x is easily negatable. */
10988 if (TREE_CODE (arg1) == INTEGER_CST
10989 && tree_int_cst_sgn (arg1) == -1
10990 && negate_expr_p (arg0)
10991 && (tem = negate_expr (arg1)) != arg1
10992 && !TREE_OVERFLOW (tem))
10993 return fold_build2_loc (loc, MULT_EXPR, type,
10994 fold_convert_loc (loc, type,
10995 negate_expr (arg0)),
10998 /* (a * (1 << b)) is (a << b) */
10999 if (TREE_CODE (arg1) == LSHIFT_EXPR
11000 && integer_onep (TREE_OPERAND (arg1, 0)))
11001 return fold_build2_loc (loc, LSHIFT_EXPR, type, op0,
11002 TREE_OPERAND (arg1, 1));
11003 if (TREE_CODE (arg0) == LSHIFT_EXPR
11004 && integer_onep (TREE_OPERAND (arg0, 0)))
11005 return fold_build2_loc (loc, LSHIFT_EXPR, type, op1,
11006 TREE_OPERAND (arg0, 1));
11008 /* (A + A) * C -> A * 2 * C */
11009 if (TREE_CODE (arg0) == PLUS_EXPR
11010 && TREE_CODE (arg1) == INTEGER_CST
11011 && operand_equal_p (TREE_OPERAND (arg0, 0),
11012 TREE_OPERAND (arg0, 1), 0))
11013 return fold_build2_loc (loc, MULT_EXPR, type,
11014 omit_one_operand_loc (loc, type,
11015 TREE_OPERAND (arg0, 0),
11016 TREE_OPERAND (arg0, 1)),
11017 fold_build2_loc (loc, MULT_EXPR, type,
11018 build_int_cst (type, 2) , arg1));
11020 strict_overflow_p = false;
11021 if (TREE_CODE (arg1) == INTEGER_CST
11022 && 0 != (tem = extract_muldiv (op0, arg1, code, NULL_TREE,
11023 &strict_overflow_p)))
11025 if (strict_overflow_p)
11026 fold_overflow_warning (("assuming signed overflow does not "
11027 "occur when simplifying "
11029 WARN_STRICT_OVERFLOW_MISC);
11030 return fold_convert_loc (loc, type, tem);
11033 /* Optimize z * conj(z) for integer complex numbers. */
11034 if (TREE_CODE (arg0) == CONJ_EXPR
11035 && operand_equal_p (TREE_OPERAND (arg0, 0), arg1, 0))
11036 return fold_mult_zconjz (loc, type, arg1);
11037 if (TREE_CODE (arg1) == CONJ_EXPR
11038 && operand_equal_p (arg0, TREE_OPERAND (arg1, 0), 0))
11039 return fold_mult_zconjz (loc, type, arg0);
11043 /* Maybe fold x * 0 to 0. The expressions aren't the same
11044 when x is NaN, since x * 0 is also NaN. Nor are they the
11045 same in modes with signed zeros, since multiplying a
11046 negative value by 0 gives -0, not +0. */
11047 if (!HONOR_NANS (TYPE_MODE (TREE_TYPE (arg0)))
11048 && !HONOR_SIGNED_ZEROS (TYPE_MODE (TREE_TYPE (arg0)))
11049 && real_zerop (arg1))
11050 return omit_one_operand_loc (loc, type, arg1, arg0);
11051 /* In IEEE floating point, x*1 is not equivalent to x for snans.
11052 Likewise for complex arithmetic with signed zeros. */
11053 if (!HONOR_SNANS (TYPE_MODE (TREE_TYPE (arg0)))
11054 && (!HONOR_SIGNED_ZEROS (TYPE_MODE (TREE_TYPE (arg0)))
11055 || !COMPLEX_FLOAT_TYPE_P (TREE_TYPE (arg0)))
11056 && real_onep (arg1))
11057 return non_lvalue_loc (loc, fold_convert_loc (loc, type, arg0));
11059 /* Transform x * -1.0 into -x. */
11060 if (!HONOR_SNANS (TYPE_MODE (TREE_TYPE (arg0)))
11061 && (!HONOR_SIGNED_ZEROS (TYPE_MODE (TREE_TYPE (arg0)))
11062 || !COMPLEX_FLOAT_TYPE_P (TREE_TYPE (arg0)))
11063 && real_minus_onep (arg1))
11064 return fold_convert_loc (loc, type, negate_expr (arg0));
11066 /* Convert (C1/X)*C2 into (C1*C2)/X. This transformation may change
11067 the result for floating point types due to rounding so it is applied
11068 only if -fassociative-math was specify. */
11069 if (flag_associative_math
11070 && TREE_CODE (arg0) == RDIV_EXPR
11071 && TREE_CODE (arg1) == REAL_CST
11072 && TREE_CODE (TREE_OPERAND (arg0, 0)) == REAL_CST)
11074 tree tem = const_binop (MULT_EXPR, TREE_OPERAND (arg0, 0),
11077 return fold_build2_loc (loc, RDIV_EXPR, type, tem,
11078 TREE_OPERAND (arg0, 1));
11081 /* Strip sign operations from X in X*X, i.e. -Y*-Y -> Y*Y. */
11082 if (operand_equal_p (arg0, arg1, 0))
11084 tree tem = fold_strip_sign_ops (arg0);
11085 if (tem != NULL_TREE)
11087 tem = fold_convert_loc (loc, type, tem);
11088 return fold_build2_loc (loc, MULT_EXPR, type, tem, tem);
11092 /* Fold z * +-I to __complex__ (-+__imag z, +-__real z).
11093 This is not the same for NaNs or if signed zeros are
11095 if (!HONOR_NANS (TYPE_MODE (TREE_TYPE (arg0)))
11096 && !HONOR_SIGNED_ZEROS (TYPE_MODE (TREE_TYPE (arg0)))
11097 && COMPLEX_FLOAT_TYPE_P (TREE_TYPE (arg0))
11098 && TREE_CODE (arg1) == COMPLEX_CST
11099 && real_zerop (TREE_REALPART (arg1)))
11101 tree rtype = TREE_TYPE (TREE_TYPE (arg0));
11102 if (real_onep (TREE_IMAGPART (arg1)))
11104 fold_build2_loc (loc, COMPLEX_EXPR, type,
11105 negate_expr (fold_build1_loc (loc, IMAGPART_EXPR,
11107 fold_build1_loc (loc, REALPART_EXPR, rtype, arg0));
11108 else if (real_minus_onep (TREE_IMAGPART (arg1)))
11110 fold_build2_loc (loc, COMPLEX_EXPR, type,
11111 fold_build1_loc (loc, IMAGPART_EXPR, rtype, arg0),
11112 negate_expr (fold_build1_loc (loc, REALPART_EXPR,
11116 /* Optimize z * conj(z) for floating point complex numbers.
11117 Guarded by flag_unsafe_math_optimizations as non-finite
11118 imaginary components don't produce scalar results. */
11119 if (flag_unsafe_math_optimizations
11120 && TREE_CODE (arg0) == CONJ_EXPR
11121 && operand_equal_p (TREE_OPERAND (arg0, 0), arg1, 0))
11122 return fold_mult_zconjz (loc, type, arg1);
11123 if (flag_unsafe_math_optimizations
11124 && TREE_CODE (arg1) == CONJ_EXPR
11125 && operand_equal_p (arg0, TREE_OPERAND (arg1, 0), 0))
11126 return fold_mult_zconjz (loc, type, arg0);
11128 if (flag_unsafe_math_optimizations)
11130 enum built_in_function fcode0 = builtin_mathfn_code (arg0);
11131 enum built_in_function fcode1 = builtin_mathfn_code (arg1);
11133 /* Optimizations of root(...)*root(...). */
11134 if (fcode0 == fcode1 && BUILTIN_ROOT_P (fcode0))
11137 tree arg00 = CALL_EXPR_ARG (arg0, 0);
11138 tree arg10 = CALL_EXPR_ARG (arg1, 0);
11140 /* Optimize sqrt(x)*sqrt(x) as x. */
11141 if (BUILTIN_SQRT_P (fcode0)
11142 && operand_equal_p (arg00, arg10, 0)
11143 && ! HONOR_SNANS (TYPE_MODE (type)))
11146 /* Optimize root(x)*root(y) as root(x*y). */
11147 rootfn = TREE_OPERAND (CALL_EXPR_FN (arg0), 0);
11148 arg = fold_build2_loc (loc, MULT_EXPR, type, arg00, arg10);
11149 return build_call_expr_loc (loc, rootfn, 1, arg);
11152 /* Optimize expN(x)*expN(y) as expN(x+y). */
11153 if (fcode0 == fcode1 && BUILTIN_EXPONENT_P (fcode0))
11155 tree expfn = TREE_OPERAND (CALL_EXPR_FN (arg0), 0);
11156 tree arg = fold_build2_loc (loc, PLUS_EXPR, type,
11157 CALL_EXPR_ARG (arg0, 0),
11158 CALL_EXPR_ARG (arg1, 0));
11159 return build_call_expr_loc (loc, expfn, 1, arg);
11162 /* Optimizations of pow(...)*pow(...). */
11163 if ((fcode0 == BUILT_IN_POW && fcode1 == BUILT_IN_POW)
11164 || (fcode0 == BUILT_IN_POWF && fcode1 == BUILT_IN_POWF)
11165 || (fcode0 == BUILT_IN_POWL && fcode1 == BUILT_IN_POWL))
11167 tree arg00 = CALL_EXPR_ARG (arg0, 0);
11168 tree arg01 = CALL_EXPR_ARG (arg0, 1);
11169 tree arg10 = CALL_EXPR_ARG (arg1, 0);
11170 tree arg11 = CALL_EXPR_ARG (arg1, 1);
11172 /* Optimize pow(x,y)*pow(z,y) as pow(x*z,y). */
11173 if (operand_equal_p (arg01, arg11, 0))
11175 tree powfn = TREE_OPERAND (CALL_EXPR_FN (arg0), 0);
11176 tree arg = fold_build2_loc (loc, MULT_EXPR, type,
11178 return build_call_expr_loc (loc, powfn, 2, arg, arg01);
11181 /* Optimize pow(x,y)*pow(x,z) as pow(x,y+z). */
11182 if (operand_equal_p (arg00, arg10, 0))
11184 tree powfn = TREE_OPERAND (CALL_EXPR_FN (arg0), 0);
11185 tree arg = fold_build2_loc (loc, PLUS_EXPR, type,
11187 return build_call_expr_loc (loc, powfn, 2, arg00, arg);
11191 /* Optimize tan(x)*cos(x) as sin(x). */
11192 if (((fcode0 == BUILT_IN_TAN && fcode1 == BUILT_IN_COS)
11193 || (fcode0 == BUILT_IN_TANF && fcode1 == BUILT_IN_COSF)
11194 || (fcode0 == BUILT_IN_TANL && fcode1 == BUILT_IN_COSL)
11195 || (fcode0 == BUILT_IN_COS && fcode1 == BUILT_IN_TAN)
11196 || (fcode0 == BUILT_IN_COSF && fcode1 == BUILT_IN_TANF)
11197 || (fcode0 == BUILT_IN_COSL && fcode1 == BUILT_IN_TANL))
11198 && operand_equal_p (CALL_EXPR_ARG (arg0, 0),
11199 CALL_EXPR_ARG (arg1, 0), 0))
11201 tree sinfn = mathfn_built_in (type, BUILT_IN_SIN);
11203 if (sinfn != NULL_TREE)
11204 return build_call_expr_loc (loc, sinfn, 1,
11205 CALL_EXPR_ARG (arg0, 0));
11208 /* Optimize x*pow(x,c) as pow(x,c+1). */
11209 if (fcode1 == BUILT_IN_POW
11210 || fcode1 == BUILT_IN_POWF
11211 || fcode1 == BUILT_IN_POWL)
11213 tree arg10 = CALL_EXPR_ARG (arg1, 0);
11214 tree arg11 = CALL_EXPR_ARG (arg1, 1);
11215 if (TREE_CODE (arg11) == REAL_CST
11216 && !TREE_OVERFLOW (arg11)
11217 && operand_equal_p (arg0, arg10, 0))
11219 tree powfn = TREE_OPERAND (CALL_EXPR_FN (arg1), 0);
11223 c = TREE_REAL_CST (arg11);
11224 real_arithmetic (&c, PLUS_EXPR, &c, &dconst1);
11225 arg = build_real (type, c);
11226 return build_call_expr_loc (loc, powfn, 2, arg0, arg);
11230 /* Optimize pow(x,c)*x as pow(x,c+1). */
11231 if (fcode0 == BUILT_IN_POW
11232 || fcode0 == BUILT_IN_POWF
11233 || fcode0 == BUILT_IN_POWL)
11235 tree arg00 = CALL_EXPR_ARG (arg0, 0);
11236 tree arg01 = CALL_EXPR_ARG (arg0, 1);
11237 if (TREE_CODE (arg01) == REAL_CST
11238 && !TREE_OVERFLOW (arg01)
11239 && operand_equal_p (arg1, arg00, 0))
11241 tree powfn = TREE_OPERAND (CALL_EXPR_FN (arg0), 0);
11245 c = TREE_REAL_CST (arg01);
11246 real_arithmetic (&c, PLUS_EXPR, &c, &dconst1);
11247 arg = build_real (type, c);
11248 return build_call_expr_loc (loc, powfn, 2, arg1, arg);
11252 /* Optimize x*x as pow(x,2.0), which is expanded as x*x. */
11253 if (optimize_function_for_speed_p (cfun)
11254 && operand_equal_p (arg0, arg1, 0))
11256 tree powfn = mathfn_built_in (type, BUILT_IN_POW);
11260 tree arg = build_real (type, dconst2);
11261 return build_call_expr_loc (loc, powfn, 2, arg0, arg);
11270 if (integer_all_onesp (arg1))
11271 return omit_one_operand_loc (loc, type, arg1, arg0);
11272 if (integer_zerop (arg1))
11273 return non_lvalue_loc (loc, fold_convert_loc (loc, type, arg0));
11274 if (operand_equal_p (arg0, arg1, 0))
11275 return non_lvalue_loc (loc, fold_convert_loc (loc, type, arg0));
11277 /* ~X | X is -1. */
11278 if (TREE_CODE (arg0) == BIT_NOT_EXPR
11279 && operand_equal_p (TREE_OPERAND (arg0, 0), arg1, 0))
11281 t1 = fold_convert_loc (loc, type, integer_zero_node);
11282 t1 = fold_unary_loc (loc, BIT_NOT_EXPR, type, t1);
11283 return omit_one_operand_loc (loc, type, t1, arg1);
11286 /* X | ~X is -1. */
11287 if (TREE_CODE (arg1) == BIT_NOT_EXPR
11288 && operand_equal_p (arg0, TREE_OPERAND (arg1, 0), 0))
11290 t1 = fold_convert_loc (loc, type, integer_zero_node);
11291 t1 = fold_unary_loc (loc, BIT_NOT_EXPR, type, t1);
11292 return omit_one_operand_loc (loc, type, t1, arg0);
11295 /* Canonicalize (X & C1) | C2. */
11296 if (TREE_CODE (arg0) == BIT_AND_EXPR
11297 && TREE_CODE (arg1) == INTEGER_CST
11298 && TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST)
11300 unsigned HOST_WIDE_INT hi1, lo1, hi2, lo2, hi3, lo3, mlo, mhi;
11301 int width = TYPE_PRECISION (type), w;
11302 hi1 = TREE_INT_CST_HIGH (TREE_OPERAND (arg0, 1));
11303 lo1 = TREE_INT_CST_LOW (TREE_OPERAND (arg0, 1));
11304 hi2 = TREE_INT_CST_HIGH (arg1);
11305 lo2 = TREE_INT_CST_LOW (arg1);
11307 /* If (C1&C2) == C1, then (X&C1)|C2 becomes (X,C2). */
11308 if ((hi1 & hi2) == hi1 && (lo1 & lo2) == lo1)
11309 return omit_one_operand_loc (loc, type, arg1,
11310 TREE_OPERAND (arg0, 0));
11312 if (width > HOST_BITS_PER_WIDE_INT)
11314 mhi = (unsigned HOST_WIDE_INT) -1
11315 >> (2 * HOST_BITS_PER_WIDE_INT - width);
11321 mlo = (unsigned HOST_WIDE_INT) -1
11322 >> (HOST_BITS_PER_WIDE_INT - width);
11325 /* If (C1|C2) == ~0 then (X&C1)|C2 becomes X|C2. */
11326 if ((~(hi1 | hi2) & mhi) == 0 && (~(lo1 | lo2) & mlo) == 0)
11327 return fold_build2_loc (loc, BIT_IOR_EXPR, type,
11328 TREE_OPERAND (arg0, 0), arg1);
11330 /* Minimize the number of bits set in C1, i.e. C1 := C1 & ~C2,
11331 unless (C1 & ~C2) | (C2 & C3) for some C3 is a mask of some
11332 mode which allows further optimizations. */
11339 for (w = BITS_PER_UNIT;
11340 w <= width && w <= HOST_BITS_PER_WIDE_INT;
11343 unsigned HOST_WIDE_INT mask
11344 = (unsigned HOST_WIDE_INT) -1 >> (HOST_BITS_PER_WIDE_INT - w);
11345 if (((lo1 | lo2) & mask) == mask
11346 && (lo1 & ~mask) == 0 && hi1 == 0)
11353 if (hi3 != hi1 || lo3 != lo1)
11354 return fold_build2_loc (loc, BIT_IOR_EXPR, type,
11355 fold_build2_loc (loc, BIT_AND_EXPR, type,
11356 TREE_OPERAND (arg0, 0),
11357 build_int_cst_wide (type,
11362 /* (X & Y) | Y is (X, Y). */
11363 if (TREE_CODE (arg0) == BIT_AND_EXPR
11364 && operand_equal_p (TREE_OPERAND (arg0, 1), arg1, 0))
11365 return omit_one_operand_loc (loc, type, arg1, TREE_OPERAND (arg0, 0));
11366 /* (X & Y) | X is (Y, X). */
11367 if (TREE_CODE (arg0) == BIT_AND_EXPR
11368 && operand_equal_p (TREE_OPERAND (arg0, 0), arg1, 0)
11369 && reorder_operands_p (TREE_OPERAND (arg0, 1), arg1))
11370 return omit_one_operand_loc (loc, type, arg1, TREE_OPERAND (arg0, 1));
11371 /* X | (X & Y) is (Y, X). */
11372 if (TREE_CODE (arg1) == BIT_AND_EXPR
11373 && operand_equal_p (arg0, TREE_OPERAND (arg1, 0), 0)
11374 && reorder_operands_p (arg0, TREE_OPERAND (arg1, 1)))
11375 return omit_one_operand_loc (loc, type, arg0, TREE_OPERAND (arg1, 1));
11376 /* X | (Y & X) is (Y, X). */
11377 if (TREE_CODE (arg1) == BIT_AND_EXPR
11378 && operand_equal_p (arg0, TREE_OPERAND (arg1, 1), 0)
11379 && reorder_operands_p (arg0, TREE_OPERAND (arg1, 0)))
11380 return omit_one_operand_loc (loc, type, arg0, TREE_OPERAND (arg1, 0));
11382 t1 = distribute_bit_expr (loc, code, type, arg0, arg1);
11383 if (t1 != NULL_TREE)
11386 /* Convert (or (not arg0) (not arg1)) to (not (and (arg0) (arg1))).
11388 This results in more efficient code for machines without a NAND
11389 instruction. Combine will canonicalize to the first form
11390 which will allow use of NAND instructions provided by the
11391 backend if they exist. */
11392 if (TREE_CODE (arg0) == BIT_NOT_EXPR
11393 && TREE_CODE (arg1) == BIT_NOT_EXPR)
11396 fold_build1_loc (loc, BIT_NOT_EXPR, type,
11397 build2 (BIT_AND_EXPR, type,
11398 fold_convert_loc (loc, type,
11399 TREE_OPERAND (arg0, 0)),
11400 fold_convert_loc (loc, type,
11401 TREE_OPERAND (arg1, 0))));
11404 /* See if this can be simplified into a rotate first. If that
11405 is unsuccessful continue in the association code. */
11409 if (integer_zerop (arg1))
11410 return non_lvalue_loc (loc, fold_convert_loc (loc, type, arg0));
11411 if (integer_all_onesp (arg1))
11412 return fold_build1_loc (loc, BIT_NOT_EXPR, type, op0);
11413 if (operand_equal_p (arg0, arg1, 0))
11414 return omit_one_operand_loc (loc, type, integer_zero_node, arg0);
11416 /* ~X ^ X is -1. */
11417 if (TREE_CODE (arg0) == BIT_NOT_EXPR
11418 && operand_equal_p (TREE_OPERAND (arg0, 0), arg1, 0))
11420 t1 = fold_convert_loc (loc, type, integer_zero_node);
11421 t1 = fold_unary_loc (loc, BIT_NOT_EXPR, type, t1);
11422 return omit_one_operand_loc (loc, type, t1, arg1);
11425 /* X ^ ~X is -1. */
11426 if (TREE_CODE (arg1) == BIT_NOT_EXPR
11427 && operand_equal_p (arg0, TREE_OPERAND (arg1, 0), 0))
11429 t1 = fold_convert_loc (loc, type, integer_zero_node);
11430 t1 = fold_unary_loc (loc, BIT_NOT_EXPR, type, t1);
11431 return omit_one_operand_loc (loc, type, t1, arg0);
11434 /* If we are XORing two BIT_AND_EXPR's, both of which are and'ing
11435 with a constant, and the two constants have no bits in common,
11436 we should treat this as a BIT_IOR_EXPR since this may produce more
11437 simplifications. */
11438 if (TREE_CODE (arg0) == BIT_AND_EXPR
11439 && TREE_CODE (arg1) == BIT_AND_EXPR
11440 && TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST
11441 && TREE_CODE (TREE_OPERAND (arg1, 1)) == INTEGER_CST
11442 && integer_zerop (const_binop (BIT_AND_EXPR,
11443 TREE_OPERAND (arg0, 1),
11444 TREE_OPERAND (arg1, 1), 0)))
11446 code = BIT_IOR_EXPR;
11450 /* (X | Y) ^ X -> Y & ~ X*/
11451 if (TREE_CODE (arg0) == BIT_IOR_EXPR
11452 && operand_equal_p (TREE_OPERAND (arg0, 0), arg1, 0))
11454 tree t2 = TREE_OPERAND (arg0, 1);
11455 t1 = fold_build1_loc (loc, BIT_NOT_EXPR, TREE_TYPE (arg1),
11457 t1 = fold_build2_loc (loc, BIT_AND_EXPR, type,
11458 fold_convert_loc (loc, type, t2),
11459 fold_convert_loc (loc, type, t1));
11463 /* (Y | X) ^ X -> Y & ~ X*/
11464 if (TREE_CODE (arg0) == BIT_IOR_EXPR
11465 && operand_equal_p (TREE_OPERAND (arg0, 1), arg1, 0))
11467 tree t2 = TREE_OPERAND (arg0, 0);
11468 t1 = fold_build1_loc (loc, BIT_NOT_EXPR, TREE_TYPE (arg1),
11470 t1 = fold_build2_loc (loc, BIT_AND_EXPR, type,
11471 fold_convert_loc (loc, type, t2),
11472 fold_convert_loc (loc, type, t1));
11476 /* X ^ (X | Y) -> Y & ~ X*/
11477 if (TREE_CODE (arg1) == BIT_IOR_EXPR
11478 && operand_equal_p (TREE_OPERAND (arg1, 0), arg0, 0))
11480 tree t2 = TREE_OPERAND (arg1, 1);
11481 t1 = fold_build1_loc (loc, BIT_NOT_EXPR, TREE_TYPE (arg0),
11483 t1 = fold_build2_loc (loc, BIT_AND_EXPR, type,
11484 fold_convert_loc (loc, type, t2),
11485 fold_convert_loc (loc, type, t1));
11489 /* X ^ (Y | X) -> Y & ~ X*/
11490 if (TREE_CODE (arg1) == BIT_IOR_EXPR
11491 && operand_equal_p (TREE_OPERAND (arg1, 1), arg0, 0))
11493 tree t2 = TREE_OPERAND (arg1, 0);
11494 t1 = fold_build1_loc (loc, BIT_NOT_EXPR, TREE_TYPE (arg0),
11496 t1 = fold_build2_loc (loc, BIT_AND_EXPR, type,
11497 fold_convert_loc (loc, type, t2),
11498 fold_convert_loc (loc, type, t1));
11502 /* Convert ~X ^ ~Y to X ^ Y. */
11503 if (TREE_CODE (arg0) == BIT_NOT_EXPR
11504 && TREE_CODE (arg1) == BIT_NOT_EXPR)
11505 return fold_build2_loc (loc, code, type,
11506 fold_convert_loc (loc, type,
11507 TREE_OPERAND (arg0, 0)),
11508 fold_convert_loc (loc, type,
11509 TREE_OPERAND (arg1, 0)));
11511 /* Convert ~X ^ C to X ^ ~C. */
11512 if (TREE_CODE (arg0) == BIT_NOT_EXPR
11513 && TREE_CODE (arg1) == INTEGER_CST)
11514 return fold_build2_loc (loc, code, type,
11515 fold_convert_loc (loc, type,
11516 TREE_OPERAND (arg0, 0)),
11517 fold_build1_loc (loc, BIT_NOT_EXPR, type, arg1));
11519 /* Fold (X & 1) ^ 1 as (X & 1) == 0. */
11520 if (TREE_CODE (arg0) == BIT_AND_EXPR
11521 && integer_onep (TREE_OPERAND (arg0, 1))
11522 && integer_onep (arg1))
11523 return fold_build2_loc (loc, EQ_EXPR, type, arg0,
11524 build_int_cst (TREE_TYPE (arg0), 0));
11526 /* Fold (X & Y) ^ Y as ~X & Y. */
11527 if (TREE_CODE (arg0) == BIT_AND_EXPR
11528 && operand_equal_p (TREE_OPERAND (arg0, 1), arg1, 0))
11530 tem = fold_convert_loc (loc, type, TREE_OPERAND (arg0, 0));
11531 return fold_build2_loc (loc, BIT_AND_EXPR, type,
11532 fold_build1_loc (loc, BIT_NOT_EXPR, type, tem),
11533 fold_convert_loc (loc, type, arg1));
11535 /* Fold (X & Y) ^ X as ~Y & X. */
11536 if (TREE_CODE (arg0) == BIT_AND_EXPR
11537 && operand_equal_p (TREE_OPERAND (arg0, 0), arg1, 0)
11538 && reorder_operands_p (TREE_OPERAND (arg0, 1), arg1))
11540 tem = fold_convert_loc (loc, type, TREE_OPERAND (arg0, 1));
11541 return fold_build2_loc (loc, BIT_AND_EXPR, type,
11542 fold_build1_loc (loc, BIT_NOT_EXPR, type, tem),
11543 fold_convert_loc (loc, type, arg1));
11545 /* Fold X ^ (X & Y) as X & ~Y. */
11546 if (TREE_CODE (arg1) == BIT_AND_EXPR
11547 && operand_equal_p (arg0, TREE_OPERAND (arg1, 0), 0))
11549 tem = fold_convert_loc (loc, type, TREE_OPERAND (arg1, 1));
11550 return fold_build2_loc (loc, BIT_AND_EXPR, type,
11551 fold_convert_loc (loc, type, arg0),
11552 fold_build1_loc (loc, BIT_NOT_EXPR, type, tem));
11554 /* Fold X ^ (Y & X) as ~Y & X. */
11555 if (TREE_CODE (arg1) == BIT_AND_EXPR
11556 && operand_equal_p (arg0, TREE_OPERAND (arg1, 1), 0)
11557 && reorder_operands_p (arg0, TREE_OPERAND (arg1, 0)))
11559 tem = fold_convert_loc (loc, type, TREE_OPERAND (arg1, 0));
11560 return fold_build2_loc (loc, BIT_AND_EXPR, type,
11561 fold_build1_loc (loc, BIT_NOT_EXPR, type, tem),
11562 fold_convert_loc (loc, type, arg0));
11565 /* See if this can be simplified into a rotate first. If that
11566 is unsuccessful continue in the association code. */
11570 if (integer_all_onesp (arg1))
11571 return non_lvalue_loc (loc, fold_convert_loc (loc, type, arg0));
11572 if (integer_zerop (arg1))
11573 return omit_one_operand_loc (loc, type, arg1, arg0);
11574 if (operand_equal_p (arg0, arg1, 0))
11575 return non_lvalue_loc (loc, fold_convert_loc (loc, type, arg0));
11577 /* ~X & X is always zero. */
11578 if (TREE_CODE (arg0) == BIT_NOT_EXPR
11579 && operand_equal_p (TREE_OPERAND (arg0, 0), arg1, 0))
11580 return omit_one_operand_loc (loc, type, integer_zero_node, arg1);
11582 /* X & ~X is always zero. */
11583 if (TREE_CODE (arg1) == BIT_NOT_EXPR
11584 && operand_equal_p (arg0, TREE_OPERAND (arg1, 0), 0))
11585 return omit_one_operand_loc (loc, type, integer_zero_node, arg0);
11587 /* Canonicalize (X | C1) & C2 as (X & C2) | (C1 & C2). */
11588 if (TREE_CODE (arg0) == BIT_IOR_EXPR
11589 && TREE_CODE (arg1) == INTEGER_CST
11590 && TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST)
11592 tree tmp1 = fold_convert_loc (loc, type, arg1);
11593 tree tmp2 = fold_convert_loc (loc, type, TREE_OPERAND (arg0, 0));
11594 tree tmp3 = fold_convert_loc (loc, type, TREE_OPERAND (arg0, 1));
11595 tmp2 = fold_build2_loc (loc, BIT_AND_EXPR, type, tmp2, tmp1);
11596 tmp3 = fold_build2_loc (loc, BIT_AND_EXPR, type, tmp3, tmp1);
11598 fold_convert_loc (loc, type,
11599 fold_build2_loc (loc, BIT_IOR_EXPR,
11600 type, tmp2, tmp3));
11603 /* (X | Y) & Y is (X, Y). */
11604 if (TREE_CODE (arg0) == BIT_IOR_EXPR
11605 && operand_equal_p (TREE_OPERAND (arg0, 1), arg1, 0))
11606 return omit_one_operand_loc (loc, type, arg1, TREE_OPERAND (arg0, 0));
11607 /* (X | Y) & X is (Y, X). */
11608 if (TREE_CODE (arg0) == BIT_IOR_EXPR
11609 && operand_equal_p (TREE_OPERAND (arg0, 0), arg1, 0)
11610 && reorder_operands_p (TREE_OPERAND (arg0, 1), arg1))
11611 return omit_one_operand_loc (loc, type, arg1, TREE_OPERAND (arg0, 1));
11612 /* X & (X | Y) is (Y, X). */
11613 if (TREE_CODE (arg1) == BIT_IOR_EXPR
11614 && operand_equal_p (arg0, TREE_OPERAND (arg1, 0), 0)
11615 && reorder_operands_p (arg0, TREE_OPERAND (arg1, 1)))
11616 return omit_one_operand_loc (loc, type, arg0, TREE_OPERAND (arg1, 1));
11617 /* X & (Y | X) is (Y, X). */
11618 if (TREE_CODE (arg1) == BIT_IOR_EXPR
11619 && operand_equal_p (arg0, TREE_OPERAND (arg1, 1), 0)
11620 && reorder_operands_p (arg0, TREE_OPERAND (arg1, 0)))
11621 return omit_one_operand_loc (loc, type, arg0, TREE_OPERAND (arg1, 0));
11623 /* Fold (X ^ 1) & 1 as (X & 1) == 0. */
11624 if (TREE_CODE (arg0) == BIT_XOR_EXPR
11625 && integer_onep (TREE_OPERAND (arg0, 1))
11626 && integer_onep (arg1))
11628 tem = TREE_OPERAND (arg0, 0);
11629 return fold_build2_loc (loc, EQ_EXPR, type,
11630 fold_build2_loc (loc, BIT_AND_EXPR, TREE_TYPE (tem), tem,
11631 build_int_cst (TREE_TYPE (tem), 1)),
11632 build_int_cst (TREE_TYPE (tem), 0));
11634 /* Fold ~X & 1 as (X & 1) == 0. */
11635 if (TREE_CODE (arg0) == BIT_NOT_EXPR
11636 && integer_onep (arg1))
11638 tem = TREE_OPERAND (arg0, 0);
11639 return fold_build2_loc (loc, EQ_EXPR, type,
11640 fold_build2_loc (loc, BIT_AND_EXPR, TREE_TYPE (tem), tem,
11641 build_int_cst (TREE_TYPE (tem), 1)),
11642 build_int_cst (TREE_TYPE (tem), 0));
11645 /* Fold (X ^ Y) & Y as ~X & Y. */
11646 if (TREE_CODE (arg0) == BIT_XOR_EXPR
11647 && operand_equal_p (TREE_OPERAND (arg0, 1), arg1, 0))
11649 tem = fold_convert_loc (loc, type, TREE_OPERAND (arg0, 0));
11650 return fold_build2_loc (loc, BIT_AND_EXPR, type,
11651 fold_build1_loc (loc, BIT_NOT_EXPR, type, tem),
11652 fold_convert_loc (loc, type, arg1));
11654 /* Fold (X ^ Y) & X as ~Y & X. */
11655 if (TREE_CODE (arg0) == BIT_XOR_EXPR
11656 && operand_equal_p (TREE_OPERAND (arg0, 0), arg1, 0)
11657 && reorder_operands_p (TREE_OPERAND (arg0, 1), arg1))
11659 tem = fold_convert_loc (loc, type, TREE_OPERAND (arg0, 1));
11660 return fold_build2_loc (loc, BIT_AND_EXPR, type,
11661 fold_build1_loc (loc, BIT_NOT_EXPR, type, tem),
11662 fold_convert_loc (loc, type, arg1));
11664 /* Fold X & (X ^ Y) as X & ~Y. */
11665 if (TREE_CODE (arg1) == BIT_XOR_EXPR
11666 && operand_equal_p (arg0, TREE_OPERAND (arg1, 0), 0))
11668 tem = fold_convert_loc (loc, type, TREE_OPERAND (arg1, 1));
11669 return fold_build2_loc (loc, BIT_AND_EXPR, type,
11670 fold_convert_loc (loc, type, arg0),
11671 fold_build1_loc (loc, BIT_NOT_EXPR, type, tem));
11673 /* Fold X & (Y ^ X) as ~Y & X. */
11674 if (TREE_CODE (arg1) == BIT_XOR_EXPR
11675 && operand_equal_p (arg0, TREE_OPERAND (arg1, 1), 0)
11676 && reorder_operands_p (arg0, TREE_OPERAND (arg1, 0)))
11678 tem = fold_convert_loc (loc, type, TREE_OPERAND (arg1, 0));
11679 return fold_build2_loc (loc, BIT_AND_EXPR, type,
11680 fold_build1_loc (loc, BIT_NOT_EXPR, type, tem),
11681 fold_convert_loc (loc, type, arg0));
11684 t1 = distribute_bit_expr (loc, code, type, arg0, arg1);
11685 if (t1 != NULL_TREE)
11687 /* Simplify ((int)c & 0377) into (int)c, if c is unsigned char. */
11688 if (TREE_CODE (arg1) == INTEGER_CST && TREE_CODE (arg0) == NOP_EXPR
11689 && TYPE_UNSIGNED (TREE_TYPE (TREE_OPERAND (arg0, 0))))
11692 = TYPE_PRECISION (TREE_TYPE (TREE_OPERAND (arg0, 0)));
11694 if (prec < BITS_PER_WORD && prec < HOST_BITS_PER_WIDE_INT
11695 && (~TREE_INT_CST_LOW (arg1)
11696 & (((HOST_WIDE_INT) 1 << prec) - 1)) == 0)
11698 fold_convert_loc (loc, type, TREE_OPERAND (arg0, 0));
11701 /* Convert (and (not arg0) (not arg1)) to (not (or (arg0) (arg1))).
11703 This results in more efficient code for machines without a NOR
11704 instruction. Combine will canonicalize to the first form
11705 which will allow use of NOR instructions provided by the
11706 backend if they exist. */
11707 if (TREE_CODE (arg0) == BIT_NOT_EXPR
11708 && TREE_CODE (arg1) == BIT_NOT_EXPR)
11710 return fold_build1_loc (loc, BIT_NOT_EXPR, type,
11711 build2 (BIT_IOR_EXPR, type,
11712 fold_convert_loc (loc, type,
11713 TREE_OPERAND (arg0, 0)),
11714 fold_convert_loc (loc, type,
11715 TREE_OPERAND (arg1, 0))));
11718 /* If arg0 is derived from the address of an object or function, we may
11719 be able to fold this expression using the object or function's
11721 if (POINTER_TYPE_P (TREE_TYPE (arg0)) && host_integerp (arg1, 1))
11723 unsigned HOST_WIDE_INT modulus, residue;
11724 unsigned HOST_WIDE_INT low = TREE_INT_CST_LOW (arg1);
11726 modulus = get_pointer_modulus_and_residue (arg0, &residue,
11727 integer_onep (arg1));
11729 /* This works because modulus is a power of 2. If this weren't the
11730 case, we'd have to replace it by its greatest power-of-2
11731 divisor: modulus & -modulus. */
11733 return build_int_cst (type, residue & low);
11736 /* Fold (X << C1) & C2 into (X << C1) & (C2 | ((1 << C1) - 1))
11737 (X >> C1) & C2 into (X >> C1) & (C2 | ~((type) -1 >> C1))
11738 if the new mask might be further optimized. */
11739 if ((TREE_CODE (arg0) == LSHIFT_EXPR
11740 || TREE_CODE (arg0) == RSHIFT_EXPR)
11741 && host_integerp (TREE_OPERAND (arg0, 1), 1)
11742 && host_integerp (arg1, TYPE_UNSIGNED (TREE_TYPE (arg1)))
11743 && tree_low_cst (TREE_OPERAND (arg0, 1), 1)
11744 < TYPE_PRECISION (TREE_TYPE (arg0))
11745 && TYPE_PRECISION (TREE_TYPE (arg0)) <= HOST_BITS_PER_WIDE_INT
11746 && tree_low_cst (TREE_OPERAND (arg0, 1), 1) > 0)
11748 unsigned int shiftc = tree_low_cst (TREE_OPERAND (arg0, 1), 1);
11749 unsigned HOST_WIDE_INT mask
11750 = tree_low_cst (arg1, TYPE_UNSIGNED (TREE_TYPE (arg1)));
11751 unsigned HOST_WIDE_INT newmask, zerobits = 0;
11752 tree shift_type = TREE_TYPE (arg0);
11754 if (TREE_CODE (arg0) == LSHIFT_EXPR)
11755 zerobits = ((((unsigned HOST_WIDE_INT) 1) << shiftc) - 1);
11756 else if (TREE_CODE (arg0) == RSHIFT_EXPR
11757 && TYPE_PRECISION (TREE_TYPE (arg0))
11758 == GET_MODE_BITSIZE (TYPE_MODE (TREE_TYPE (arg0))))
11760 unsigned int prec = TYPE_PRECISION (TREE_TYPE (arg0));
11761 tree arg00 = TREE_OPERAND (arg0, 0);
11762 /* See if more bits can be proven as zero because of
11764 if (TREE_CODE (arg00) == NOP_EXPR
11765 && TYPE_UNSIGNED (TREE_TYPE (TREE_OPERAND (arg00, 0))))
11767 tree inner_type = TREE_TYPE (TREE_OPERAND (arg00, 0));
11768 if (TYPE_PRECISION (inner_type)
11769 == GET_MODE_BITSIZE (TYPE_MODE (inner_type))
11770 && TYPE_PRECISION (inner_type) < prec)
11772 prec = TYPE_PRECISION (inner_type);
11773 /* See if we can shorten the right shift. */
11775 shift_type = inner_type;
11778 zerobits = ~(unsigned HOST_WIDE_INT) 0;
11779 zerobits >>= HOST_BITS_PER_WIDE_INT - shiftc;
11780 zerobits <<= prec - shiftc;
11781 /* For arithmetic shift if sign bit could be set, zerobits
11782 can contain actually sign bits, so no transformation is
11783 possible, unless MASK masks them all away. In that
11784 case the shift needs to be converted into logical shift. */
11785 if (!TYPE_UNSIGNED (TREE_TYPE (arg0))
11786 && prec == TYPE_PRECISION (TREE_TYPE (arg0)))
11788 if ((mask & zerobits) == 0)
11789 shift_type = unsigned_type_for (TREE_TYPE (arg0));
11795 /* ((X << 16) & 0xff00) is (X, 0). */
11796 if ((mask & zerobits) == mask)
11797 return omit_one_operand_loc (loc, type,
11798 build_int_cst (type, 0), arg0);
11800 newmask = mask | zerobits;
11801 if (newmask != mask && (newmask & (newmask + 1)) == 0)
11805 /* Only do the transformation if NEWMASK is some integer
11807 for (prec = BITS_PER_UNIT;
11808 prec < HOST_BITS_PER_WIDE_INT; prec <<= 1)
11809 if (newmask == (((unsigned HOST_WIDE_INT) 1) << prec) - 1)
11811 if (prec < HOST_BITS_PER_WIDE_INT
11812 || newmask == ~(unsigned HOST_WIDE_INT) 0)
11816 if (shift_type != TREE_TYPE (arg0))
11818 tem = fold_build2_loc (loc, TREE_CODE (arg0), shift_type,
11819 fold_convert_loc (loc, shift_type,
11820 TREE_OPERAND (arg0, 0)),
11821 TREE_OPERAND (arg0, 1));
11822 tem = fold_convert_loc (loc, type, tem);
11826 newmaskt = build_int_cst_type (TREE_TYPE (op1), newmask);
11827 if (!tree_int_cst_equal (newmaskt, arg1))
11828 return fold_build2_loc (loc, BIT_AND_EXPR, type, tem, newmaskt);
11836 /* Don't touch a floating-point divide by zero unless the mode
11837 of the constant can represent infinity. */
11838 if (TREE_CODE (arg1) == REAL_CST
11839 && !MODE_HAS_INFINITIES (TYPE_MODE (TREE_TYPE (arg1)))
11840 && real_zerop (arg1))
11843 /* Optimize A / A to 1.0 if we don't care about
11844 NaNs or Infinities. Skip the transformation
11845 for non-real operands. */
11846 if (SCALAR_FLOAT_TYPE_P (TREE_TYPE (arg0))
11847 && ! HONOR_NANS (TYPE_MODE (TREE_TYPE (arg0)))
11848 && ! HONOR_INFINITIES (TYPE_MODE (TREE_TYPE (arg0)))
11849 && operand_equal_p (arg0, arg1, 0))
11851 tree r = build_real (TREE_TYPE (arg0), dconst1);
11853 return omit_two_operands_loc (loc, type, r, arg0, arg1);
11856 /* The complex version of the above A / A optimization. */
11857 if (COMPLEX_FLOAT_TYPE_P (TREE_TYPE (arg0))
11858 && operand_equal_p (arg0, arg1, 0))
11860 tree elem_type = TREE_TYPE (TREE_TYPE (arg0));
11861 if (! HONOR_NANS (TYPE_MODE (elem_type))
11862 && ! HONOR_INFINITIES (TYPE_MODE (elem_type)))
11864 tree r = build_real (elem_type, dconst1);
11865 /* omit_two_operands will call fold_convert for us. */
11866 return omit_two_operands_loc (loc, type, r, arg0, arg1);
11870 /* (-A) / (-B) -> A / B */
11871 if (TREE_CODE (arg0) == NEGATE_EXPR && negate_expr_p (arg1))
11872 return fold_build2_loc (loc, RDIV_EXPR, type,
11873 TREE_OPERAND (arg0, 0),
11874 negate_expr (arg1));
11875 if (TREE_CODE (arg1) == NEGATE_EXPR && negate_expr_p (arg0))
11876 return fold_build2_loc (loc, RDIV_EXPR, type,
11877 negate_expr (arg0),
11878 TREE_OPERAND (arg1, 0));
11880 /* In IEEE floating point, x/1 is not equivalent to x for snans. */
11881 if (!HONOR_SNANS (TYPE_MODE (TREE_TYPE (arg0)))
11882 && real_onep (arg1))
11883 return non_lvalue_loc (loc, fold_convert_loc (loc, type, arg0));
11885 /* In IEEE floating point, x/-1 is not equivalent to -x for snans. */
11886 if (!HONOR_SNANS (TYPE_MODE (TREE_TYPE (arg0)))
11887 && real_minus_onep (arg1))
11888 return non_lvalue_loc (loc, fold_convert_loc (loc, type,
11889 negate_expr (arg0)));
11891 /* If ARG1 is a constant, we can convert this to a multiply by the
11892 reciprocal. This does not have the same rounding properties,
11893 so only do this if -freciprocal-math. We can actually
11894 always safely do it if ARG1 is a power of two, but it's hard to
11895 tell if it is or not in a portable manner. */
11896 if (TREE_CODE (arg1) == REAL_CST)
11898 if (flag_reciprocal_math
11899 && 0 != (tem = const_binop (code, build_real (type, dconst1),
11901 return fold_build2_loc (loc, MULT_EXPR, type, arg0, tem);
11902 /* Find the reciprocal if optimizing and the result is exact. */
11906 r = TREE_REAL_CST (arg1);
11907 if (exact_real_inverse (TYPE_MODE(TREE_TYPE(arg0)), &r))
11909 tem = build_real (type, r);
11910 return fold_build2_loc (loc, MULT_EXPR, type,
11911 fold_convert_loc (loc, type, arg0), tem);
11915 /* Convert A/B/C to A/(B*C). */
11916 if (flag_reciprocal_math
11917 && TREE_CODE (arg0) == RDIV_EXPR)
11918 return fold_build2_loc (loc, RDIV_EXPR, type, TREE_OPERAND (arg0, 0),
11919 fold_build2_loc (loc, MULT_EXPR, type,
11920 TREE_OPERAND (arg0, 1), arg1));
11922 /* Convert A/(B/C) to (A/B)*C. */
11923 if (flag_reciprocal_math
11924 && TREE_CODE (arg1) == RDIV_EXPR)
11925 return fold_build2_loc (loc, MULT_EXPR, type,
11926 fold_build2_loc (loc, RDIV_EXPR, type, arg0,
11927 TREE_OPERAND (arg1, 0)),
11928 TREE_OPERAND (arg1, 1));
11930 /* Convert C1/(X*C2) into (C1/C2)/X. */
11931 if (flag_reciprocal_math
11932 && TREE_CODE (arg1) == MULT_EXPR
11933 && TREE_CODE (arg0) == REAL_CST
11934 && TREE_CODE (TREE_OPERAND (arg1, 1)) == REAL_CST)
11936 tree tem = const_binop (RDIV_EXPR, arg0,
11937 TREE_OPERAND (arg1, 1), 0);
11939 return fold_build2_loc (loc, RDIV_EXPR, type, tem,
11940 TREE_OPERAND (arg1, 0));
11943 if (flag_unsafe_math_optimizations)
11945 enum built_in_function fcode0 = builtin_mathfn_code (arg0);
11946 enum built_in_function fcode1 = builtin_mathfn_code (arg1);
11948 /* Optimize sin(x)/cos(x) as tan(x). */
11949 if (((fcode0 == BUILT_IN_SIN && fcode1 == BUILT_IN_COS)
11950 || (fcode0 == BUILT_IN_SINF && fcode1 == BUILT_IN_COSF)
11951 || (fcode0 == BUILT_IN_SINL && fcode1 == BUILT_IN_COSL))
11952 && operand_equal_p (CALL_EXPR_ARG (arg0, 0),
11953 CALL_EXPR_ARG (arg1, 0), 0))
11955 tree tanfn = mathfn_built_in (type, BUILT_IN_TAN);
11957 if (tanfn != NULL_TREE)
11958 return build_call_expr_loc (loc, tanfn, 1, CALL_EXPR_ARG (arg0, 0));
11961 /* Optimize cos(x)/sin(x) as 1.0/tan(x). */
11962 if (((fcode0 == BUILT_IN_COS && fcode1 == BUILT_IN_SIN)
11963 || (fcode0 == BUILT_IN_COSF && fcode1 == BUILT_IN_SINF)
11964 || (fcode0 == BUILT_IN_COSL && fcode1 == BUILT_IN_SINL))
11965 && operand_equal_p (CALL_EXPR_ARG (arg0, 0),
11966 CALL_EXPR_ARG (arg1, 0), 0))
11968 tree tanfn = mathfn_built_in (type, BUILT_IN_TAN);
11970 if (tanfn != NULL_TREE)
11972 tree tmp = build_call_expr_loc (loc, tanfn, 1,
11973 CALL_EXPR_ARG (arg0, 0));
11974 return fold_build2_loc (loc, RDIV_EXPR, type,
11975 build_real (type, dconst1), tmp);
11979 /* Optimize sin(x)/tan(x) as cos(x) if we don't care about
11980 NaNs or Infinities. */
11981 if (((fcode0 == BUILT_IN_SIN && fcode1 == BUILT_IN_TAN)
11982 || (fcode0 == BUILT_IN_SINF && fcode1 == BUILT_IN_TANF)
11983 || (fcode0 == BUILT_IN_SINL && fcode1 == BUILT_IN_TANL)))
11985 tree arg00 = CALL_EXPR_ARG (arg0, 0);
11986 tree arg01 = CALL_EXPR_ARG (arg1, 0);
11988 if (! HONOR_NANS (TYPE_MODE (TREE_TYPE (arg00)))
11989 && ! HONOR_INFINITIES (TYPE_MODE (TREE_TYPE (arg00)))
11990 && operand_equal_p (arg00, arg01, 0))
11992 tree cosfn = mathfn_built_in (type, BUILT_IN_COS);
11994 if (cosfn != NULL_TREE)
11995 return build_call_expr_loc (loc, cosfn, 1, arg00);
11999 /* Optimize tan(x)/sin(x) as 1.0/cos(x) if we don't care about
12000 NaNs or Infinities. */
12001 if (((fcode0 == BUILT_IN_TAN && fcode1 == BUILT_IN_SIN)
12002 || (fcode0 == BUILT_IN_TANF && fcode1 == BUILT_IN_SINF)
12003 || (fcode0 == BUILT_IN_TANL && fcode1 == BUILT_IN_SINL)))
12005 tree arg00 = CALL_EXPR_ARG (arg0, 0);
12006 tree arg01 = CALL_EXPR_ARG (arg1, 0);
12008 if (! HONOR_NANS (TYPE_MODE (TREE_TYPE (arg00)))
12009 && ! HONOR_INFINITIES (TYPE_MODE (TREE_TYPE (arg00)))
12010 && operand_equal_p (arg00, arg01, 0))
12012 tree cosfn = mathfn_built_in (type, BUILT_IN_COS);
12014 if (cosfn != NULL_TREE)
12016 tree tmp = build_call_expr_loc (loc, cosfn, 1, arg00);
12017 return fold_build2_loc (loc, RDIV_EXPR, type,
12018 build_real (type, dconst1),
12024 /* Optimize pow(x,c)/x as pow(x,c-1). */
12025 if (fcode0 == BUILT_IN_POW
12026 || fcode0 == BUILT_IN_POWF
12027 || fcode0 == BUILT_IN_POWL)
12029 tree arg00 = CALL_EXPR_ARG (arg0, 0);
12030 tree arg01 = CALL_EXPR_ARG (arg0, 1);
12031 if (TREE_CODE (arg01) == REAL_CST
12032 && !TREE_OVERFLOW (arg01)
12033 && operand_equal_p (arg1, arg00, 0))
12035 tree powfn = TREE_OPERAND (CALL_EXPR_FN (arg0), 0);
12039 c = TREE_REAL_CST (arg01);
12040 real_arithmetic (&c, MINUS_EXPR, &c, &dconst1);
12041 arg = build_real (type, c);
12042 return build_call_expr_loc (loc, powfn, 2, arg1, arg);
12046 /* Optimize a/root(b/c) into a*root(c/b). */
12047 if (BUILTIN_ROOT_P (fcode1))
12049 tree rootarg = CALL_EXPR_ARG (arg1, 0);
12051 if (TREE_CODE (rootarg) == RDIV_EXPR)
12053 tree rootfn = TREE_OPERAND (CALL_EXPR_FN (arg1), 0);
12054 tree b = TREE_OPERAND (rootarg, 0);
12055 tree c = TREE_OPERAND (rootarg, 1);
12057 tree tmp = fold_build2_loc (loc, RDIV_EXPR, type, c, b);
12059 tmp = build_call_expr_loc (loc, rootfn, 1, tmp);
12060 return fold_build2_loc (loc, MULT_EXPR, type, arg0, tmp);
12064 /* Optimize x/expN(y) into x*expN(-y). */
12065 if (BUILTIN_EXPONENT_P (fcode1))
12067 tree expfn = TREE_OPERAND (CALL_EXPR_FN (arg1), 0);
12068 tree arg = negate_expr (CALL_EXPR_ARG (arg1, 0));
12069 arg1 = build_call_expr_loc (loc,
12071 fold_convert_loc (loc, type, arg));
12072 return fold_build2_loc (loc, MULT_EXPR, type, arg0, arg1);
12075 /* Optimize x/pow(y,z) into x*pow(y,-z). */
12076 if (fcode1 == BUILT_IN_POW
12077 || fcode1 == BUILT_IN_POWF
12078 || fcode1 == BUILT_IN_POWL)
12080 tree powfn = TREE_OPERAND (CALL_EXPR_FN (arg1), 0);
12081 tree arg10 = CALL_EXPR_ARG (arg1, 0);
12082 tree arg11 = CALL_EXPR_ARG (arg1, 1);
12083 tree neg11 = fold_convert_loc (loc, type,
12084 negate_expr (arg11));
12085 arg1 = build_call_expr_loc (loc, powfn, 2, arg10, neg11);
12086 return fold_build2_loc (loc, MULT_EXPR, type, arg0, arg1);
12091 case TRUNC_DIV_EXPR:
12092 case FLOOR_DIV_EXPR:
12093 /* Simplify A / (B << N) where A and B are positive and B is
12094 a power of 2, to A >> (N + log2(B)). */
12095 strict_overflow_p = false;
12096 if (TREE_CODE (arg1) == LSHIFT_EXPR
12097 && (TYPE_UNSIGNED (type)
12098 || tree_expr_nonnegative_warnv_p (op0, &strict_overflow_p)))
12100 tree sval = TREE_OPERAND (arg1, 0);
12101 if (integer_pow2p (sval) && tree_int_cst_sgn (sval) > 0)
12103 tree sh_cnt = TREE_OPERAND (arg1, 1);
12104 unsigned long pow2 = exact_log2 (TREE_INT_CST_LOW (sval));
12106 if (strict_overflow_p)
12107 fold_overflow_warning (("assuming signed overflow does not "
12108 "occur when simplifying A / (B << N)"),
12109 WARN_STRICT_OVERFLOW_MISC);
12111 sh_cnt = fold_build2_loc (loc, PLUS_EXPR, TREE_TYPE (sh_cnt),
12112 sh_cnt, build_int_cst (NULL_TREE, pow2));
12113 return fold_build2_loc (loc, RSHIFT_EXPR, type,
12114 fold_convert_loc (loc, type, arg0), sh_cnt);
12118 /* For unsigned integral types, FLOOR_DIV_EXPR is the same as
12119 TRUNC_DIV_EXPR. Rewrite into the latter in this case. */
12120 if (INTEGRAL_TYPE_P (type)
12121 && TYPE_UNSIGNED (type)
12122 && code == FLOOR_DIV_EXPR)
12123 return fold_build2_loc (loc, TRUNC_DIV_EXPR, type, op0, op1);
12127 case ROUND_DIV_EXPR:
12128 case CEIL_DIV_EXPR:
12129 case EXACT_DIV_EXPR:
12130 if (integer_onep (arg1))
12131 return non_lvalue_loc (loc, fold_convert_loc (loc, type, arg0));
12132 if (integer_zerop (arg1))
12134 /* X / -1 is -X. */
12135 if (!TYPE_UNSIGNED (type)
12136 && TREE_CODE (arg1) == INTEGER_CST
12137 && TREE_INT_CST_LOW (arg1) == (unsigned HOST_WIDE_INT) -1
12138 && TREE_INT_CST_HIGH (arg1) == -1)
12139 return fold_convert_loc (loc, type, negate_expr (arg0));
12141 /* Convert -A / -B to A / B when the type is signed and overflow is
12143 if ((!INTEGRAL_TYPE_P (type) || TYPE_OVERFLOW_UNDEFINED (type))
12144 && TREE_CODE (arg0) == NEGATE_EXPR
12145 && negate_expr_p (arg1))
12147 if (INTEGRAL_TYPE_P (type))
12148 fold_overflow_warning (("assuming signed overflow does not occur "
12149 "when distributing negation across "
12151 WARN_STRICT_OVERFLOW_MISC);
12152 return fold_build2_loc (loc, code, type,
12153 fold_convert_loc (loc, type,
12154 TREE_OPERAND (arg0, 0)),
12155 fold_convert_loc (loc, type,
12156 negate_expr (arg1)));
12158 if ((!INTEGRAL_TYPE_P (type) || TYPE_OVERFLOW_UNDEFINED (type))
12159 && TREE_CODE (arg1) == NEGATE_EXPR
12160 && negate_expr_p (arg0))
12162 if (INTEGRAL_TYPE_P (type))
12163 fold_overflow_warning (("assuming signed overflow does not occur "
12164 "when distributing negation across "
12166 WARN_STRICT_OVERFLOW_MISC);
12167 return fold_build2_loc (loc, code, type,
12168 fold_convert_loc (loc, type,
12169 negate_expr (arg0)),
12170 fold_convert_loc (loc, type,
12171 TREE_OPERAND (arg1, 0)));
12174 /* If arg0 is a multiple of arg1, then rewrite to the fastest div
12175 operation, EXACT_DIV_EXPR.
12177 Note that only CEIL_DIV_EXPR and FLOOR_DIV_EXPR are rewritten now.
12178 At one time others generated faster code, it's not clear if they do
12179 after the last round to changes to the DIV code in expmed.c. */
12180 if ((code == CEIL_DIV_EXPR || code == FLOOR_DIV_EXPR)
12181 && multiple_of_p (type, arg0, arg1))
12182 return fold_build2_loc (loc, EXACT_DIV_EXPR, type, arg0, arg1);
12184 strict_overflow_p = false;
12185 if (TREE_CODE (arg1) == INTEGER_CST
12186 && 0 != (tem = extract_muldiv (op0, arg1, code, NULL_TREE,
12187 &strict_overflow_p)))
12189 if (strict_overflow_p)
12190 fold_overflow_warning (("assuming signed overflow does not occur "
12191 "when simplifying division"),
12192 WARN_STRICT_OVERFLOW_MISC);
12193 return fold_convert_loc (loc, type, tem);
12198 case CEIL_MOD_EXPR:
12199 case FLOOR_MOD_EXPR:
12200 case ROUND_MOD_EXPR:
12201 case TRUNC_MOD_EXPR:
12202 /* X % 1 is always zero, but be sure to preserve any side
12204 if (integer_onep (arg1))
12205 return omit_one_operand_loc (loc, type, integer_zero_node, arg0);
12207 /* X % 0, return X % 0 unchanged so that we can get the
12208 proper warnings and errors. */
12209 if (integer_zerop (arg1))
12212 /* 0 % X is always zero, but be sure to preserve any side
12213 effects in X. Place this after checking for X == 0. */
12214 if (integer_zerop (arg0))
12215 return omit_one_operand_loc (loc, type, integer_zero_node, arg1);
12217 /* X % -1 is zero. */
12218 if (!TYPE_UNSIGNED (type)
12219 && TREE_CODE (arg1) == INTEGER_CST
12220 && TREE_INT_CST_LOW (arg1) == (unsigned HOST_WIDE_INT) -1
12221 && TREE_INT_CST_HIGH (arg1) == -1)
12222 return omit_one_operand_loc (loc, type, integer_zero_node, arg0);
12224 /* Optimize TRUNC_MOD_EXPR by a power of two into a BIT_AND_EXPR,
12225 i.e. "X % C" into "X & (C - 1)", if X and C are positive. */
12226 strict_overflow_p = false;
12227 if ((code == TRUNC_MOD_EXPR || code == FLOOR_MOD_EXPR)
12228 && (TYPE_UNSIGNED (type)
12229 || tree_expr_nonnegative_warnv_p (op0, &strict_overflow_p)))
12232 /* Also optimize A % (C << N) where C is a power of 2,
12233 to A & ((C << N) - 1). */
12234 if (TREE_CODE (arg1) == LSHIFT_EXPR)
12235 c = TREE_OPERAND (arg1, 0);
12237 if (integer_pow2p (c) && tree_int_cst_sgn (c) > 0)
12239 tree mask = fold_build2_loc (loc, MINUS_EXPR, TREE_TYPE (arg1), arg1,
12240 build_int_cst (TREE_TYPE (arg1), 1));
12241 if (strict_overflow_p)
12242 fold_overflow_warning (("assuming signed overflow does not "
12243 "occur when simplifying "
12244 "X % (power of two)"),
12245 WARN_STRICT_OVERFLOW_MISC);
12246 return fold_build2_loc (loc, BIT_AND_EXPR, type,
12247 fold_convert_loc (loc, type, arg0),
12248 fold_convert_loc (loc, type, mask));
12252 /* X % -C is the same as X % C. */
12253 if (code == TRUNC_MOD_EXPR
12254 && !TYPE_UNSIGNED (type)
12255 && TREE_CODE (arg1) == INTEGER_CST
12256 && !TREE_OVERFLOW (arg1)
12257 && TREE_INT_CST_HIGH (arg1) < 0
12258 && !TYPE_OVERFLOW_TRAPS (type)
12259 /* Avoid this transformation if C is INT_MIN, i.e. C == -C. */
12260 && !sign_bit_p (arg1, arg1))
12261 return fold_build2_loc (loc, code, type,
12262 fold_convert_loc (loc, type, arg0),
12263 fold_convert_loc (loc, type,
12264 negate_expr (arg1)));
12266 /* X % -Y is the same as X % Y. */
12267 if (code == TRUNC_MOD_EXPR
12268 && !TYPE_UNSIGNED (type)
12269 && TREE_CODE (arg1) == NEGATE_EXPR
12270 && !TYPE_OVERFLOW_TRAPS (type))
12271 return fold_build2_loc (loc, code, type, fold_convert_loc (loc, type, arg0),
12272 fold_convert_loc (loc, type,
12273 TREE_OPERAND (arg1, 0)));
12275 if (TREE_CODE (arg1) == INTEGER_CST
12276 && 0 != (tem = extract_muldiv (op0, arg1, code, NULL_TREE,
12277 &strict_overflow_p)))
12279 if (strict_overflow_p)
12280 fold_overflow_warning (("assuming signed overflow does not occur "
12281 "when simplifying modulus"),
12282 WARN_STRICT_OVERFLOW_MISC);
12283 return fold_convert_loc (loc, type, tem);
12290 if (integer_all_onesp (arg0))
12291 return omit_one_operand_loc (loc, type, arg0, arg1);
12295 /* Optimize -1 >> x for arithmetic right shifts. */
12296 if (integer_all_onesp (arg0) && !TYPE_UNSIGNED (type)
12297 && tree_expr_nonnegative_p (arg1))
12298 return omit_one_operand_loc (loc, type, arg0, arg1);
12299 /* ... fall through ... */
12303 if (integer_zerop (arg1))
12304 return non_lvalue_loc (loc, fold_convert_loc (loc, type, arg0));
12305 if (integer_zerop (arg0))
12306 return omit_one_operand_loc (loc, type, arg0, arg1);
12308 /* Since negative shift count is not well-defined,
12309 don't try to compute it in the compiler. */
12310 if (TREE_CODE (arg1) == INTEGER_CST && tree_int_cst_sgn (arg1) < 0)
12313 /* Turn (a OP c1) OP c2 into a OP (c1+c2). */
12314 if (TREE_CODE (op0) == code && host_integerp (arg1, false)
12315 && TREE_INT_CST_LOW (arg1) < TYPE_PRECISION (type)
12316 && host_integerp (TREE_OPERAND (arg0, 1), false)
12317 && TREE_INT_CST_LOW (TREE_OPERAND (arg0, 1)) < TYPE_PRECISION (type))
12319 HOST_WIDE_INT low = (TREE_INT_CST_LOW (TREE_OPERAND (arg0, 1))
12320 + TREE_INT_CST_LOW (arg1));
12322 /* Deal with a OP (c1 + c2) being undefined but (a OP c1) OP c2
12323 being well defined. */
12324 if (low >= TYPE_PRECISION (type))
12326 if (code == LROTATE_EXPR || code == RROTATE_EXPR)
12327 low = low % TYPE_PRECISION (type);
12328 else if (TYPE_UNSIGNED (type) || code == LSHIFT_EXPR)
12329 return omit_one_operand_loc (loc, type, build_int_cst (type, 0),
12330 TREE_OPERAND (arg0, 0));
12332 low = TYPE_PRECISION (type) - 1;
12335 return fold_build2_loc (loc, code, type, TREE_OPERAND (arg0, 0),
12336 build_int_cst (type, low));
12339 /* Transform (x >> c) << c into x & (-1<<c), or transform (x << c) >> c
12340 into x & ((unsigned)-1 >> c) for unsigned types. */
12341 if (((code == LSHIFT_EXPR && TREE_CODE (arg0) == RSHIFT_EXPR)
12342 || (TYPE_UNSIGNED (type)
12343 && code == RSHIFT_EXPR && TREE_CODE (arg0) == LSHIFT_EXPR))
12344 && host_integerp (arg1, false)
12345 && TREE_INT_CST_LOW (arg1) < TYPE_PRECISION (type)
12346 && host_integerp (TREE_OPERAND (arg0, 1), false)
12347 && TREE_INT_CST_LOW (TREE_OPERAND (arg0, 1)) < TYPE_PRECISION (type))
12349 HOST_WIDE_INT low0 = TREE_INT_CST_LOW (TREE_OPERAND (arg0, 1));
12350 HOST_WIDE_INT low1 = TREE_INT_CST_LOW (arg1);
12356 arg00 = fold_convert_loc (loc, type, TREE_OPERAND (arg0, 0));
12358 lshift = build_int_cst (type, -1);
12359 lshift = int_const_binop (code, lshift, arg1, 0);
12361 return fold_build2_loc (loc, BIT_AND_EXPR, type, arg00, lshift);
12365 /* Rewrite an LROTATE_EXPR by a constant into an
12366 RROTATE_EXPR by a new constant. */
12367 if (code == LROTATE_EXPR && TREE_CODE (arg1) == INTEGER_CST)
12369 tree tem = build_int_cst (TREE_TYPE (arg1),
12370 TYPE_PRECISION (type));
12371 tem = const_binop (MINUS_EXPR, tem, arg1, 0);
12372 return fold_build2_loc (loc, RROTATE_EXPR, type, op0, tem);
12375 /* If we have a rotate of a bit operation with the rotate count and
12376 the second operand of the bit operation both constant,
12377 permute the two operations. */
12378 if (code == RROTATE_EXPR && TREE_CODE (arg1) == INTEGER_CST
12379 && (TREE_CODE (arg0) == BIT_AND_EXPR
12380 || TREE_CODE (arg0) == BIT_IOR_EXPR
12381 || TREE_CODE (arg0) == BIT_XOR_EXPR)
12382 && TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST)
12383 return fold_build2_loc (loc, TREE_CODE (arg0), type,
12384 fold_build2_loc (loc, code, type,
12385 TREE_OPERAND (arg0, 0), arg1),
12386 fold_build2_loc (loc, code, type,
12387 TREE_OPERAND (arg0, 1), arg1));
12389 /* Two consecutive rotates adding up to the precision of the
12390 type can be ignored. */
12391 if (code == RROTATE_EXPR && TREE_CODE (arg1) == INTEGER_CST
12392 && TREE_CODE (arg0) == RROTATE_EXPR
12393 && TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST
12394 && TREE_INT_CST_HIGH (arg1) == 0
12395 && TREE_INT_CST_HIGH (TREE_OPERAND (arg0, 1)) == 0
12396 && ((TREE_INT_CST_LOW (arg1)
12397 + TREE_INT_CST_LOW (TREE_OPERAND (arg0, 1)))
12398 == (unsigned int) TYPE_PRECISION (type)))
12399 return TREE_OPERAND (arg0, 0);
12401 /* Fold (X & C2) << C1 into (X << C1) & (C2 << C1)
12402 (X & C2) >> C1 into (X >> C1) & (C2 >> C1)
12403 if the latter can be further optimized. */
12404 if ((code == LSHIFT_EXPR || code == RSHIFT_EXPR)
12405 && TREE_CODE (arg0) == BIT_AND_EXPR
12406 && TREE_CODE (arg1) == INTEGER_CST
12407 && TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST)
12409 tree mask = fold_build2_loc (loc, code, type,
12410 fold_convert_loc (loc, type,
12411 TREE_OPERAND (arg0, 1)),
12413 tree shift = fold_build2_loc (loc, code, type,
12414 fold_convert_loc (loc, type,
12415 TREE_OPERAND (arg0, 0)),
12417 tem = fold_binary_loc (loc, BIT_AND_EXPR, type, shift, mask);
12425 if (operand_equal_p (arg0, arg1, 0))
12426 return omit_one_operand_loc (loc, type, arg0, arg1);
12427 if (INTEGRAL_TYPE_P (type)
12428 && operand_equal_p (arg1, TYPE_MIN_VALUE (type), OEP_ONLY_CONST))
12429 return omit_one_operand_loc (loc, type, arg1, arg0);
12430 tem = fold_minmax (loc, MIN_EXPR, type, arg0, arg1);
12436 if (operand_equal_p (arg0, arg1, 0))
12437 return omit_one_operand_loc (loc, type, arg0, arg1);
12438 if (INTEGRAL_TYPE_P (type)
12439 && TYPE_MAX_VALUE (type)
12440 && operand_equal_p (arg1, TYPE_MAX_VALUE (type), OEP_ONLY_CONST))
12441 return omit_one_operand_loc (loc, type, arg1, arg0);
12442 tem = fold_minmax (loc, MAX_EXPR, type, arg0, arg1);
12447 case TRUTH_ANDIF_EXPR:
12448 /* Note that the operands of this must be ints
12449 and their values must be 0 or 1.
12450 ("true" is a fixed value perhaps depending on the language.) */
12451 /* If first arg is constant zero, return it. */
12452 if (integer_zerop (arg0))
12453 return fold_convert_loc (loc, type, arg0);
12454 case TRUTH_AND_EXPR:
12455 /* If either arg is constant true, drop it. */
12456 if (TREE_CODE (arg0) == INTEGER_CST && ! integer_zerop (arg0))
12457 return non_lvalue_loc (loc, fold_convert_loc (loc, type, arg1));
12458 if (TREE_CODE (arg1) == INTEGER_CST && ! integer_zerop (arg1)
12459 /* Preserve sequence points. */
12460 && (code != TRUTH_ANDIF_EXPR || ! TREE_SIDE_EFFECTS (arg0)))
12461 return non_lvalue_loc (loc, fold_convert_loc (loc, type, arg0));
12462 /* If second arg is constant zero, result is zero, but first arg
12463 must be evaluated. */
12464 if (integer_zerop (arg1))
12465 return omit_one_operand_loc (loc, type, arg1, arg0);
12466 /* Likewise for first arg, but note that only the TRUTH_AND_EXPR
12467 case will be handled here. */
12468 if (integer_zerop (arg0))
12469 return omit_one_operand_loc (loc, type, arg0, arg1);
12471 /* !X && X is always false. */
12472 if (TREE_CODE (arg0) == TRUTH_NOT_EXPR
12473 && operand_equal_p (TREE_OPERAND (arg0, 0), arg1, 0))
12474 return omit_one_operand_loc (loc, type, integer_zero_node, arg1);
12475 /* X && !X is always false. */
12476 if (TREE_CODE (arg1) == TRUTH_NOT_EXPR
12477 && operand_equal_p (arg0, TREE_OPERAND (arg1, 0), 0))
12478 return omit_one_operand_loc (loc, type, integer_zero_node, arg0);
12480 /* A < X && A + 1 > Y ==> A < X && A >= Y. Normally A + 1 > Y
12481 means A >= Y && A != MAX, but in this case we know that
12484 if (!TREE_SIDE_EFFECTS (arg0)
12485 && !TREE_SIDE_EFFECTS (arg1))
12487 tem = fold_to_nonsharp_ineq_using_bound (loc, arg0, arg1);
12488 if (tem && !operand_equal_p (tem, arg0, 0))
12489 return fold_build2_loc (loc, code, type, tem, arg1);
12491 tem = fold_to_nonsharp_ineq_using_bound (loc, arg1, arg0);
12492 if (tem && !operand_equal_p (tem, arg1, 0))
12493 return fold_build2_loc (loc, code, type, arg0, tem);
12497 /* We only do these simplifications if we are optimizing. */
12501 /* Check for things like (A || B) && (A || C). We can convert this
12502 to A || (B && C). Note that either operator can be any of the four
12503 truth and/or operations and the transformation will still be
12504 valid. Also note that we only care about order for the
12505 ANDIF and ORIF operators. If B contains side effects, this
12506 might change the truth-value of A. */
12507 if (TREE_CODE (arg0) == TREE_CODE (arg1)
12508 && (TREE_CODE (arg0) == TRUTH_ANDIF_EXPR
12509 || TREE_CODE (arg0) == TRUTH_ORIF_EXPR
12510 || TREE_CODE (arg0) == TRUTH_AND_EXPR
12511 || TREE_CODE (arg0) == TRUTH_OR_EXPR)
12512 && ! TREE_SIDE_EFFECTS (TREE_OPERAND (arg0, 1)))
12514 tree a00 = TREE_OPERAND (arg0, 0);
12515 tree a01 = TREE_OPERAND (arg0, 1);
12516 tree a10 = TREE_OPERAND (arg1, 0);
12517 tree a11 = TREE_OPERAND (arg1, 1);
12518 int commutative = ((TREE_CODE (arg0) == TRUTH_OR_EXPR
12519 || TREE_CODE (arg0) == TRUTH_AND_EXPR)
12520 && (code == TRUTH_AND_EXPR
12521 || code == TRUTH_OR_EXPR));
12523 if (operand_equal_p (a00, a10, 0))
12524 return fold_build2_loc (loc, TREE_CODE (arg0), type, a00,
12525 fold_build2_loc (loc, code, type, a01, a11));
12526 else if (commutative && operand_equal_p (a00, a11, 0))
12527 return fold_build2_loc (loc, TREE_CODE (arg0), type, a00,
12528 fold_build2_loc (loc, code, type, a01, a10));
12529 else if (commutative && operand_equal_p (a01, a10, 0))
12530 return fold_build2_loc (loc, TREE_CODE (arg0), type, a01,
12531 fold_build2_loc (loc, code, type, a00, a11));
12533 /* This case if tricky because we must either have commutative
12534 operators or else A10 must not have side-effects. */
12536 else if ((commutative || ! TREE_SIDE_EFFECTS (a10))
12537 && operand_equal_p (a01, a11, 0))
12538 return fold_build2_loc (loc, TREE_CODE (arg0), type,
12539 fold_build2_loc (loc, code, type, a00, a10),
12543 /* See if we can build a range comparison. */
12544 if (0 != (tem = fold_range_test (loc, code, type, op0, op1)))
12547 /* Check for the possibility of merging component references. If our
12548 lhs is another similar operation, try to merge its rhs with our
12549 rhs. Then try to merge our lhs and rhs. */
12550 if (TREE_CODE (arg0) == code
12551 && 0 != (tem = fold_truthop (loc, code, type,
12552 TREE_OPERAND (arg0, 1), arg1)))
12553 return fold_build2_loc (loc, code, type, TREE_OPERAND (arg0, 0), tem);
12555 if ((tem = fold_truthop (loc, code, type, arg0, arg1)) != 0)
12560 case TRUTH_ORIF_EXPR:
12561 /* Note that the operands of this must be ints
12562 and their values must be 0 or true.
12563 ("true" is a fixed value perhaps depending on the language.) */
12564 /* If first arg is constant true, return it. */
12565 if (TREE_CODE (arg0) == INTEGER_CST && ! integer_zerop (arg0))
12566 return fold_convert_loc (loc, type, arg0);
12567 case TRUTH_OR_EXPR:
12568 /* If either arg is constant zero, drop it. */
12569 if (TREE_CODE (arg0) == INTEGER_CST && integer_zerop (arg0))
12570 return non_lvalue_loc (loc, fold_convert_loc (loc, type, arg1));
12571 if (TREE_CODE (arg1) == INTEGER_CST && integer_zerop (arg1)
12572 /* Preserve sequence points. */
12573 && (code != TRUTH_ORIF_EXPR || ! TREE_SIDE_EFFECTS (arg0)))
12574 return non_lvalue_loc (loc, fold_convert_loc (loc, type, arg0));
12575 /* If second arg is constant true, result is true, but we must
12576 evaluate first arg. */
12577 if (TREE_CODE (arg1) == INTEGER_CST && ! integer_zerop (arg1))
12578 return omit_one_operand_loc (loc, type, arg1, arg0);
12579 /* Likewise for first arg, but note this only occurs here for
12581 if (TREE_CODE (arg0) == INTEGER_CST && ! integer_zerop (arg0))
12582 return omit_one_operand_loc (loc, type, arg0, arg1);
12584 /* !X || X is always true. */
12585 if (TREE_CODE (arg0) == TRUTH_NOT_EXPR
12586 && operand_equal_p (TREE_OPERAND (arg0, 0), arg1, 0))
12587 return omit_one_operand_loc (loc, type, integer_one_node, arg1);
12588 /* X || !X is always true. */
12589 if (TREE_CODE (arg1) == TRUTH_NOT_EXPR
12590 && operand_equal_p (arg0, TREE_OPERAND (arg1, 0), 0))
12591 return omit_one_operand_loc (loc, type, integer_one_node, arg0);
12595 case TRUTH_XOR_EXPR:
12596 /* If the second arg is constant zero, drop it. */
12597 if (integer_zerop (arg1))
12598 return non_lvalue_loc (loc, fold_convert_loc (loc, type, arg0));
12599 /* If the second arg is constant true, this is a logical inversion. */
12600 if (integer_onep (arg1))
12602 /* Only call invert_truthvalue if operand is a truth value. */
12603 if (TREE_CODE (TREE_TYPE (arg0)) != BOOLEAN_TYPE)
12604 tem = fold_build1_loc (loc, TRUTH_NOT_EXPR, TREE_TYPE (arg0), arg0);
12606 tem = invert_truthvalue_loc (loc, arg0);
12607 return non_lvalue_loc (loc, fold_convert_loc (loc, type, tem));
12609 /* Identical arguments cancel to zero. */
12610 if (operand_equal_p (arg0, arg1, 0))
12611 return omit_one_operand_loc (loc, type, integer_zero_node, arg0);
12613 /* !X ^ X is always true. */
12614 if (TREE_CODE (arg0) == TRUTH_NOT_EXPR
12615 && operand_equal_p (TREE_OPERAND (arg0, 0), arg1, 0))
12616 return omit_one_operand_loc (loc, type, integer_one_node, arg1);
12618 /* X ^ !X is always true. */
12619 if (TREE_CODE (arg1) == TRUTH_NOT_EXPR
12620 && operand_equal_p (arg0, TREE_OPERAND (arg1, 0), 0))
12621 return omit_one_operand_loc (loc, type, integer_one_node, arg0);
12627 tem = fold_comparison (loc, code, type, op0, op1);
12628 if (tem != NULL_TREE)
12631 /* bool_var != 0 becomes bool_var. */
12632 if (TREE_CODE (TREE_TYPE (arg0)) == BOOLEAN_TYPE && integer_zerop (arg1)
12633 && code == NE_EXPR)
12634 return non_lvalue_loc (loc, fold_convert_loc (loc, type, arg0));
12636 /* bool_var == 1 becomes bool_var. */
12637 if (TREE_CODE (TREE_TYPE (arg0)) == BOOLEAN_TYPE && integer_onep (arg1)
12638 && code == EQ_EXPR)
12639 return non_lvalue_loc (loc, fold_convert_loc (loc, type, arg0));
12641 /* bool_var != 1 becomes !bool_var. */
12642 if (TREE_CODE (TREE_TYPE (arg0)) == BOOLEAN_TYPE && integer_onep (arg1)
12643 && code == NE_EXPR)
12644 return fold_build1_loc (loc, TRUTH_NOT_EXPR, type,
12645 fold_convert_loc (loc, type, arg0));
12647 /* bool_var == 0 becomes !bool_var. */
12648 if (TREE_CODE (TREE_TYPE (arg0)) == BOOLEAN_TYPE && integer_zerop (arg1)
12649 && code == EQ_EXPR)
12650 return fold_build1_loc (loc, TRUTH_NOT_EXPR, type,
12651 fold_convert_loc (loc, type, arg0));
12653 /* !exp != 0 becomes !exp */
12654 if (TREE_CODE (arg0) == TRUTH_NOT_EXPR && integer_zerop (arg1)
12655 && code == NE_EXPR)
12656 return non_lvalue_loc (loc, fold_convert_loc (loc, type, arg0));
12658 /* If this is an equality comparison of the address of two non-weak,
12659 unaliased symbols neither of which are extern (since we do not
12660 have access to attributes for externs), then we know the result. */
12661 if (TREE_CODE (arg0) == ADDR_EXPR
12662 && VAR_OR_FUNCTION_DECL_P (TREE_OPERAND (arg0, 0))
12663 && ! DECL_WEAK (TREE_OPERAND (arg0, 0))
12664 && ! lookup_attribute ("alias",
12665 DECL_ATTRIBUTES (TREE_OPERAND (arg0, 0)))
12666 && ! DECL_EXTERNAL (TREE_OPERAND (arg0, 0))
12667 && TREE_CODE (arg1) == ADDR_EXPR
12668 && VAR_OR_FUNCTION_DECL_P (TREE_OPERAND (arg1, 0))
12669 && ! DECL_WEAK (TREE_OPERAND (arg1, 0))
12670 && ! lookup_attribute ("alias",
12671 DECL_ATTRIBUTES (TREE_OPERAND (arg1, 0)))
12672 && ! DECL_EXTERNAL (TREE_OPERAND (arg1, 0)))
12674 /* We know that we're looking at the address of two
12675 non-weak, unaliased, static _DECL nodes.
12677 It is both wasteful and incorrect to call operand_equal_p
12678 to compare the two ADDR_EXPR nodes. It is wasteful in that
12679 all we need to do is test pointer equality for the arguments
12680 to the two ADDR_EXPR nodes. It is incorrect to use
12681 operand_equal_p as that function is NOT equivalent to a
12682 C equality test. It can in fact return false for two
12683 objects which would test as equal using the C equality
12685 bool equal = TREE_OPERAND (arg0, 0) == TREE_OPERAND (arg1, 0);
12686 return constant_boolean_node (equal
12687 ? code == EQ_EXPR : code != EQ_EXPR,
12691 /* If this is an EQ or NE comparison of a constant with a PLUS_EXPR or
12692 a MINUS_EXPR of a constant, we can convert it into a comparison with
12693 a revised constant as long as no overflow occurs. */
12694 if (TREE_CODE (arg1) == INTEGER_CST
12695 && (TREE_CODE (arg0) == PLUS_EXPR
12696 || TREE_CODE (arg0) == MINUS_EXPR)
12697 && TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST
12698 && 0 != (tem = const_binop (TREE_CODE (arg0) == PLUS_EXPR
12699 ? MINUS_EXPR : PLUS_EXPR,
12700 fold_convert_loc (loc, TREE_TYPE (arg0),
12702 TREE_OPERAND (arg0, 1), 0))
12703 && !TREE_OVERFLOW (tem))
12704 return fold_build2_loc (loc, code, type, TREE_OPERAND (arg0, 0), tem);
12706 /* Similarly for a NEGATE_EXPR. */
12707 if (TREE_CODE (arg0) == NEGATE_EXPR
12708 && TREE_CODE (arg1) == INTEGER_CST
12709 && 0 != (tem = negate_expr (arg1))
12710 && TREE_CODE (tem) == INTEGER_CST
12711 && !TREE_OVERFLOW (tem))
12712 return fold_build2_loc (loc, code, type, TREE_OPERAND (arg0, 0), tem);
12714 /* Similarly for a BIT_XOR_EXPR; X ^ C1 == C2 is X == (C1 ^ C2). */
12715 if (TREE_CODE (arg0) == BIT_XOR_EXPR
12716 && TREE_CODE (arg1) == INTEGER_CST
12717 && TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST)
12718 return fold_build2_loc (loc, code, type, TREE_OPERAND (arg0, 0),
12719 fold_build2_loc (loc, BIT_XOR_EXPR, TREE_TYPE (arg0),
12720 fold_convert_loc (loc,
12723 TREE_OPERAND (arg0, 1)));
12725 /* Transform comparisons of the form X +- Y CMP X to Y CMP 0. */
12726 if ((TREE_CODE (arg0) == PLUS_EXPR
12727 || TREE_CODE (arg0) == POINTER_PLUS_EXPR
12728 || TREE_CODE (arg0) == MINUS_EXPR)
12729 && operand_equal_p (TREE_OPERAND (arg0, 0), arg1, 0)
12730 && (INTEGRAL_TYPE_P (TREE_TYPE (arg0))
12731 || POINTER_TYPE_P (TREE_TYPE (arg0))))
12733 tree val = TREE_OPERAND (arg0, 1);
12734 return omit_two_operands_loc (loc, type,
12735 fold_build2_loc (loc, code, type,
12737 build_int_cst (TREE_TYPE (val),
12739 TREE_OPERAND (arg0, 0), arg1);
12742 /* Transform comparisons of the form C - X CMP X if C % 2 == 1. */
12743 if (TREE_CODE (arg0) == MINUS_EXPR
12744 && TREE_CODE (TREE_OPERAND (arg0, 0)) == INTEGER_CST
12745 && operand_equal_p (TREE_OPERAND (arg0, 1), arg1, 0)
12746 && (TREE_INT_CST_LOW (TREE_OPERAND (arg0, 0)) & 1) == 1)
12748 return omit_two_operands_loc (loc, type,
12750 ? boolean_true_node : boolean_false_node,
12751 TREE_OPERAND (arg0, 1), arg1);
12754 /* If we have X - Y == 0, we can convert that to X == Y and similarly
12755 for !=. Don't do this for ordered comparisons due to overflow. */
12756 if (TREE_CODE (arg0) == MINUS_EXPR
12757 && integer_zerop (arg1))
12758 return fold_build2_loc (loc, code, type,
12759 TREE_OPERAND (arg0, 0), TREE_OPERAND (arg0, 1));
12761 /* Convert ABS_EXPR<x> == 0 or ABS_EXPR<x> != 0 to x == 0 or x != 0. */
12762 if (TREE_CODE (arg0) == ABS_EXPR
12763 && (integer_zerop (arg1) || real_zerop (arg1)))
12764 return fold_build2_loc (loc, code, type, TREE_OPERAND (arg0, 0), arg1);
12766 /* If this is an EQ or NE comparison with zero and ARG0 is
12767 (1 << foo) & bar, convert it to (bar >> foo) & 1. Both require
12768 two operations, but the latter can be done in one less insn
12769 on machines that have only two-operand insns or on which a
12770 constant cannot be the first operand. */
12771 if (TREE_CODE (arg0) == BIT_AND_EXPR
12772 && integer_zerop (arg1))
12774 tree arg00 = TREE_OPERAND (arg0, 0);
12775 tree arg01 = TREE_OPERAND (arg0, 1);
12776 if (TREE_CODE (arg00) == LSHIFT_EXPR
12777 && integer_onep (TREE_OPERAND (arg00, 0)))
12779 tree tem = fold_build2_loc (loc, RSHIFT_EXPR, TREE_TYPE (arg00),
12780 arg01, TREE_OPERAND (arg00, 1));
12781 tem = fold_build2_loc (loc, BIT_AND_EXPR, TREE_TYPE (arg0), tem,
12782 build_int_cst (TREE_TYPE (arg0), 1));
12783 return fold_build2_loc (loc, code, type,
12784 fold_convert_loc (loc, TREE_TYPE (arg1), tem),
12787 else if (TREE_CODE (arg01) == LSHIFT_EXPR
12788 && integer_onep (TREE_OPERAND (arg01, 0)))
12790 tree tem = fold_build2_loc (loc, RSHIFT_EXPR, TREE_TYPE (arg01),
12791 arg00, TREE_OPERAND (arg01, 1));
12792 tem = fold_build2_loc (loc, BIT_AND_EXPR, TREE_TYPE (arg0), tem,
12793 build_int_cst (TREE_TYPE (arg0), 1));
12794 return fold_build2_loc (loc, code, type,
12795 fold_convert_loc (loc, TREE_TYPE (arg1), tem),
12800 /* If this is an NE or EQ comparison of zero against the result of a
12801 signed MOD operation whose second operand is a power of 2, make
12802 the MOD operation unsigned since it is simpler and equivalent. */
12803 if (integer_zerop (arg1)
12804 && !TYPE_UNSIGNED (TREE_TYPE (arg0))
12805 && (TREE_CODE (arg0) == TRUNC_MOD_EXPR
12806 || TREE_CODE (arg0) == CEIL_MOD_EXPR
12807 || TREE_CODE (arg0) == FLOOR_MOD_EXPR
12808 || TREE_CODE (arg0) == ROUND_MOD_EXPR)
12809 && integer_pow2p (TREE_OPERAND (arg0, 1)))
12811 tree newtype = unsigned_type_for (TREE_TYPE (arg0));
12812 tree newmod = fold_build2_loc (loc, TREE_CODE (arg0), newtype,
12813 fold_convert_loc (loc, newtype,
12814 TREE_OPERAND (arg0, 0)),
12815 fold_convert_loc (loc, newtype,
12816 TREE_OPERAND (arg0, 1)));
12818 return fold_build2_loc (loc, code, type, newmod,
12819 fold_convert_loc (loc, newtype, arg1));
12822 /* Fold ((X >> C1) & C2) == 0 and ((X >> C1) & C2) != 0 where
12823 C1 is a valid shift constant, and C2 is a power of two, i.e.
12825 if (TREE_CODE (arg0) == BIT_AND_EXPR
12826 && TREE_CODE (TREE_OPERAND (arg0, 0)) == RSHIFT_EXPR
12827 && TREE_CODE (TREE_OPERAND (TREE_OPERAND (arg0, 0), 1))
12829 && integer_pow2p (TREE_OPERAND (arg0, 1))
12830 && integer_zerop (arg1))
12832 tree itype = TREE_TYPE (arg0);
12833 unsigned HOST_WIDE_INT prec = TYPE_PRECISION (itype);
12834 tree arg001 = TREE_OPERAND (TREE_OPERAND (arg0, 0), 1);
12836 /* Check for a valid shift count. */
12837 if (TREE_INT_CST_HIGH (arg001) == 0
12838 && TREE_INT_CST_LOW (arg001) < prec)
12840 tree arg01 = TREE_OPERAND (arg0, 1);
12841 tree arg000 = TREE_OPERAND (TREE_OPERAND (arg0, 0), 0);
12842 unsigned HOST_WIDE_INT log2 = tree_log2 (arg01);
12843 /* If (C2 << C1) doesn't overflow, then ((X >> C1) & C2) != 0
12844 can be rewritten as (X & (C2 << C1)) != 0. */
12845 if ((log2 + TREE_INT_CST_LOW (arg001)) < prec)
12847 tem = fold_build2_loc (loc, LSHIFT_EXPR, itype, arg01, arg001);
12848 tem = fold_build2_loc (loc, BIT_AND_EXPR, itype, arg000, tem);
12849 return fold_build2_loc (loc, code, type, tem, arg1);
12851 /* Otherwise, for signed (arithmetic) shifts,
12852 ((X >> C1) & C2) != 0 is rewritten as X < 0, and
12853 ((X >> C1) & C2) == 0 is rewritten as X >= 0. */
12854 else if (!TYPE_UNSIGNED (itype))
12855 return fold_build2_loc (loc, code == EQ_EXPR ? GE_EXPR : LT_EXPR, type,
12856 arg000, build_int_cst (itype, 0));
12857 /* Otherwise, of unsigned (logical) shifts,
12858 ((X >> C1) & C2) != 0 is rewritten as (X,false), and
12859 ((X >> C1) & C2) == 0 is rewritten as (X,true). */
12861 return omit_one_operand_loc (loc, type,
12862 code == EQ_EXPR ? integer_one_node
12863 : integer_zero_node,
12868 /* If this is an NE comparison of zero with an AND of one, remove the
12869 comparison since the AND will give the correct value. */
12870 if (code == NE_EXPR
12871 && integer_zerop (arg1)
12872 && TREE_CODE (arg0) == BIT_AND_EXPR
12873 && integer_onep (TREE_OPERAND (arg0, 1)))
12874 return fold_convert_loc (loc, type, arg0);
12876 /* If we have (A & C) == C where C is a power of 2, convert this into
12877 (A & C) != 0. Similarly for NE_EXPR. */
12878 if (TREE_CODE (arg0) == BIT_AND_EXPR
12879 && integer_pow2p (TREE_OPERAND (arg0, 1))
12880 && operand_equal_p (TREE_OPERAND (arg0, 1), arg1, 0))
12881 return fold_build2_loc (loc, code == EQ_EXPR ? NE_EXPR : EQ_EXPR, type,
12882 arg0, fold_convert_loc (loc, TREE_TYPE (arg0),
12883 integer_zero_node));
12885 /* If we have (A & C) != 0 or (A & C) == 0 and C is the sign
12886 bit, then fold the expression into A < 0 or A >= 0. */
12887 tem = fold_single_bit_test_into_sign_test (loc, code, arg0, arg1, type);
12891 /* If we have (A & C) == D where D & ~C != 0, convert this into 0.
12892 Similarly for NE_EXPR. */
12893 if (TREE_CODE (arg0) == BIT_AND_EXPR
12894 && TREE_CODE (arg1) == INTEGER_CST
12895 && TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST)
12897 tree notc = fold_build1_loc (loc, BIT_NOT_EXPR,
12898 TREE_TYPE (TREE_OPERAND (arg0, 1)),
12899 TREE_OPERAND (arg0, 1));
12900 tree dandnotc = fold_build2_loc (loc, BIT_AND_EXPR, TREE_TYPE (arg0),
12902 tree rslt = code == EQ_EXPR ? integer_zero_node : integer_one_node;
12903 if (integer_nonzerop (dandnotc))
12904 return omit_one_operand_loc (loc, type, rslt, arg0);
12907 /* If we have (A | C) == D where C & ~D != 0, convert this into 0.
12908 Similarly for NE_EXPR. */
12909 if (TREE_CODE (arg0) == BIT_IOR_EXPR
12910 && TREE_CODE (arg1) == INTEGER_CST
12911 && TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST)
12913 tree notd = fold_build1_loc (loc, BIT_NOT_EXPR, TREE_TYPE (arg1), arg1);
12914 tree candnotd = fold_build2_loc (loc, BIT_AND_EXPR, TREE_TYPE (arg0),
12915 TREE_OPERAND (arg0, 1), notd);
12916 tree rslt = code == EQ_EXPR ? integer_zero_node : integer_one_node;
12917 if (integer_nonzerop (candnotd))
12918 return omit_one_operand_loc (loc, type, rslt, arg0);
12921 /* If this is a comparison of a field, we may be able to simplify it. */
12922 if ((TREE_CODE (arg0) == COMPONENT_REF
12923 || TREE_CODE (arg0) == BIT_FIELD_REF)
12924 /* Handle the constant case even without -O
12925 to make sure the warnings are given. */
12926 && (optimize || TREE_CODE (arg1) == INTEGER_CST))
12928 t1 = optimize_bit_field_compare (loc, code, type, arg0, arg1);
12933 /* Optimize comparisons of strlen vs zero to a compare of the
12934 first character of the string vs zero. To wit,
12935 strlen(ptr) == 0 => *ptr == 0
12936 strlen(ptr) != 0 => *ptr != 0
12937 Other cases should reduce to one of these two (or a constant)
12938 due to the return value of strlen being unsigned. */
12939 if (TREE_CODE (arg0) == CALL_EXPR
12940 && integer_zerop (arg1))
12942 tree fndecl = get_callee_fndecl (arg0);
12945 && DECL_BUILT_IN_CLASS (fndecl) == BUILT_IN_NORMAL
12946 && DECL_FUNCTION_CODE (fndecl) == BUILT_IN_STRLEN
12947 && call_expr_nargs (arg0) == 1
12948 && TREE_CODE (TREE_TYPE (CALL_EXPR_ARG (arg0, 0))) == POINTER_TYPE)
12950 tree iref = build_fold_indirect_ref_loc (loc,
12951 CALL_EXPR_ARG (arg0, 0));
12952 return fold_build2_loc (loc, code, type, iref,
12953 build_int_cst (TREE_TYPE (iref), 0));
12957 /* Fold (X >> C) != 0 into X < 0 if C is one less than the width
12958 of X. Similarly fold (X >> C) == 0 into X >= 0. */
12959 if (TREE_CODE (arg0) == RSHIFT_EXPR
12960 && integer_zerop (arg1)
12961 && TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST)
12963 tree arg00 = TREE_OPERAND (arg0, 0);
12964 tree arg01 = TREE_OPERAND (arg0, 1);
12965 tree itype = TREE_TYPE (arg00);
12966 if (TREE_INT_CST_HIGH (arg01) == 0
12967 && TREE_INT_CST_LOW (arg01)
12968 == (unsigned HOST_WIDE_INT) (TYPE_PRECISION (itype) - 1))
12970 if (TYPE_UNSIGNED (itype))
12972 itype = signed_type_for (itype);
12973 arg00 = fold_convert_loc (loc, itype, arg00);
12975 return fold_build2_loc (loc, code == EQ_EXPR ? GE_EXPR : LT_EXPR,
12976 type, arg00, build_int_cst (itype, 0));
12980 /* (X ^ Y) == 0 becomes X == Y, and (X ^ Y) != 0 becomes X != Y. */
12981 if (integer_zerop (arg1)
12982 && TREE_CODE (arg0) == BIT_XOR_EXPR)
12983 return fold_build2_loc (loc, code, type, TREE_OPERAND (arg0, 0),
12984 TREE_OPERAND (arg0, 1));
12986 /* (X ^ Y) == Y becomes X == 0. We know that Y has no side-effects. */
12987 if (TREE_CODE (arg0) == BIT_XOR_EXPR
12988 && operand_equal_p (TREE_OPERAND (arg0, 1), arg1, 0))
12989 return fold_build2_loc (loc, code, type, TREE_OPERAND (arg0, 0),
12990 build_int_cst (TREE_TYPE (arg1), 0));
12991 /* Likewise (X ^ Y) == X becomes Y == 0. X has no side-effects. */
12992 if (TREE_CODE (arg0) == BIT_XOR_EXPR
12993 && operand_equal_p (TREE_OPERAND (arg0, 0), arg1, 0)
12994 && reorder_operands_p (TREE_OPERAND (arg0, 1), arg1))
12995 return fold_build2_loc (loc, code, type, TREE_OPERAND (arg0, 1),
12996 build_int_cst (TREE_TYPE (arg1), 0));
12998 /* (X ^ C1) op C2 can be rewritten as X op (C1 ^ C2). */
12999 if (TREE_CODE (arg0) == BIT_XOR_EXPR
13000 && TREE_CODE (arg1) == INTEGER_CST
13001 && TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST)
13002 return fold_build2_loc (loc, code, type, TREE_OPERAND (arg0, 0),
13003 fold_build2_loc (loc, BIT_XOR_EXPR, TREE_TYPE (arg1),
13004 TREE_OPERAND (arg0, 1), arg1));
13006 /* Fold (~X & C) == 0 into (X & C) != 0 and (~X & C) != 0 into
13007 (X & C) == 0 when C is a single bit. */
13008 if (TREE_CODE (arg0) == BIT_AND_EXPR
13009 && TREE_CODE (TREE_OPERAND (arg0, 0)) == BIT_NOT_EXPR
13010 && integer_zerop (arg1)
13011 && integer_pow2p (TREE_OPERAND (arg0, 1)))
13013 tem = fold_build2_loc (loc, BIT_AND_EXPR, TREE_TYPE (arg0),
13014 TREE_OPERAND (TREE_OPERAND (arg0, 0), 0),
13015 TREE_OPERAND (arg0, 1));
13016 return fold_build2_loc (loc, code == EQ_EXPR ? NE_EXPR : EQ_EXPR,
13020 /* Fold ((X & C) ^ C) eq/ne 0 into (X & C) ne/eq 0, when the
13021 constant C is a power of two, i.e. a single bit. */
13022 if (TREE_CODE (arg0) == BIT_XOR_EXPR
13023 && TREE_CODE (TREE_OPERAND (arg0, 0)) == BIT_AND_EXPR
13024 && integer_zerop (arg1)
13025 && integer_pow2p (TREE_OPERAND (arg0, 1))
13026 && operand_equal_p (TREE_OPERAND (TREE_OPERAND (arg0, 0), 1),
13027 TREE_OPERAND (arg0, 1), OEP_ONLY_CONST))
13029 tree arg00 = TREE_OPERAND (arg0, 0);
13030 return fold_build2_loc (loc, code == EQ_EXPR ? NE_EXPR : EQ_EXPR, type,
13031 arg00, build_int_cst (TREE_TYPE (arg00), 0));
13034 /* Likewise, fold ((X ^ C) & C) eq/ne 0 into (X & C) ne/eq 0,
13035 when is C is a power of two, i.e. a single bit. */
13036 if (TREE_CODE (arg0) == BIT_AND_EXPR
13037 && TREE_CODE (TREE_OPERAND (arg0, 0)) == BIT_XOR_EXPR
13038 && integer_zerop (arg1)
13039 && integer_pow2p (TREE_OPERAND (arg0, 1))
13040 && operand_equal_p (TREE_OPERAND (TREE_OPERAND (arg0, 0), 1),
13041 TREE_OPERAND (arg0, 1), OEP_ONLY_CONST))
13043 tree arg000 = TREE_OPERAND (TREE_OPERAND (arg0, 0), 0);
13044 tem = fold_build2_loc (loc, BIT_AND_EXPR, TREE_TYPE (arg000),
13045 arg000, TREE_OPERAND (arg0, 1));
13046 return fold_build2_loc (loc, code == EQ_EXPR ? NE_EXPR : EQ_EXPR, type,
13047 tem, build_int_cst (TREE_TYPE (tem), 0));
13050 if (integer_zerop (arg1)
13051 && tree_expr_nonzero_p (arg0))
13053 tree res = constant_boolean_node (code==NE_EXPR, type);
13054 return omit_one_operand_loc (loc, type, res, arg0);
13057 /* Fold -X op -Y as X op Y, where op is eq/ne. */
13058 if (TREE_CODE (arg0) == NEGATE_EXPR
13059 && TREE_CODE (arg1) == NEGATE_EXPR)
13060 return fold_build2_loc (loc, code, type,
13061 TREE_OPERAND (arg0, 0),
13062 TREE_OPERAND (arg1, 0));
13064 /* Fold (X & C) op (Y & C) as (X ^ Y) & C op 0", and symmetries. */
13065 if (TREE_CODE (arg0) == BIT_AND_EXPR
13066 && TREE_CODE (arg1) == BIT_AND_EXPR)
13068 tree arg00 = TREE_OPERAND (arg0, 0);
13069 tree arg01 = TREE_OPERAND (arg0, 1);
13070 tree arg10 = TREE_OPERAND (arg1, 0);
13071 tree arg11 = TREE_OPERAND (arg1, 1);
13072 tree itype = TREE_TYPE (arg0);
13074 if (operand_equal_p (arg01, arg11, 0))
13075 return fold_build2_loc (loc, code, type,
13076 fold_build2_loc (loc, BIT_AND_EXPR, itype,
13077 fold_build2_loc (loc,
13078 BIT_XOR_EXPR, itype,
13081 build_int_cst (itype, 0));
13083 if (operand_equal_p (arg01, arg10, 0))
13084 return fold_build2_loc (loc, code, type,
13085 fold_build2_loc (loc, BIT_AND_EXPR, itype,
13086 fold_build2_loc (loc,
13087 BIT_XOR_EXPR, itype,
13090 build_int_cst (itype, 0));
13092 if (operand_equal_p (arg00, arg11, 0))
13093 return fold_build2_loc (loc, code, type,
13094 fold_build2_loc (loc, BIT_AND_EXPR, itype,
13095 fold_build2_loc (loc,
13096 BIT_XOR_EXPR, itype,
13099 build_int_cst (itype, 0));
13101 if (operand_equal_p (arg00, arg10, 0))
13102 return fold_build2_loc (loc, code, type,
13103 fold_build2_loc (loc, BIT_AND_EXPR, itype,
13104 fold_build2_loc (loc,
13105 BIT_XOR_EXPR, itype,
13108 build_int_cst (itype, 0));
13111 if (TREE_CODE (arg0) == BIT_XOR_EXPR
13112 && TREE_CODE (arg1) == BIT_XOR_EXPR)
13114 tree arg00 = TREE_OPERAND (arg0, 0);
13115 tree arg01 = TREE_OPERAND (arg0, 1);
13116 tree arg10 = TREE_OPERAND (arg1, 0);
13117 tree arg11 = TREE_OPERAND (arg1, 1);
13118 tree itype = TREE_TYPE (arg0);
13120 /* Optimize (X ^ Z) op (Y ^ Z) as X op Y, and symmetries.
13121 operand_equal_p guarantees no side-effects so we don't need
13122 to use omit_one_operand on Z. */
13123 if (operand_equal_p (arg01, arg11, 0))
13124 return fold_build2_loc (loc, code, type, arg00, arg10);
13125 if (operand_equal_p (arg01, arg10, 0))
13126 return fold_build2_loc (loc, code, type, arg00, arg11);
13127 if (operand_equal_p (arg00, arg11, 0))
13128 return fold_build2_loc (loc, code, type, arg01, arg10);
13129 if (operand_equal_p (arg00, arg10, 0))
13130 return fold_build2_loc (loc, code, type, arg01, arg11);
13132 /* Optimize (X ^ C1) op (Y ^ C2) as (X ^ (C1 ^ C2)) op Y. */
13133 if (TREE_CODE (arg01) == INTEGER_CST
13134 && TREE_CODE (arg11) == INTEGER_CST)
13135 return fold_build2_loc (loc, code, type,
13136 fold_build2_loc (loc, BIT_XOR_EXPR, itype, arg00,
13137 fold_build2_loc (loc,
13138 BIT_XOR_EXPR, itype,
13143 /* Attempt to simplify equality/inequality comparisons of complex
13144 values. Only lower the comparison if the result is known or
13145 can be simplified to a single scalar comparison. */
13146 if ((TREE_CODE (arg0) == COMPLEX_EXPR
13147 || TREE_CODE (arg0) == COMPLEX_CST)
13148 && (TREE_CODE (arg1) == COMPLEX_EXPR
13149 || TREE_CODE (arg1) == COMPLEX_CST))
13151 tree real0, imag0, real1, imag1;
13154 if (TREE_CODE (arg0) == COMPLEX_EXPR)
13156 real0 = TREE_OPERAND (arg0, 0);
13157 imag0 = TREE_OPERAND (arg0, 1);
13161 real0 = TREE_REALPART (arg0);
13162 imag0 = TREE_IMAGPART (arg0);
13165 if (TREE_CODE (arg1) == COMPLEX_EXPR)
13167 real1 = TREE_OPERAND (arg1, 0);
13168 imag1 = TREE_OPERAND (arg1, 1);
13172 real1 = TREE_REALPART (arg1);
13173 imag1 = TREE_IMAGPART (arg1);
13176 rcond = fold_binary_loc (loc, code, type, real0, real1);
13177 if (rcond && TREE_CODE (rcond) == INTEGER_CST)
13179 if (integer_zerop (rcond))
13181 if (code == EQ_EXPR)
13182 return omit_two_operands_loc (loc, type, boolean_false_node,
13184 return fold_build2_loc (loc, NE_EXPR, type, imag0, imag1);
13188 if (code == NE_EXPR)
13189 return omit_two_operands_loc (loc, type, boolean_true_node,
13191 return fold_build2_loc (loc, EQ_EXPR, type, imag0, imag1);
13195 icond = fold_binary_loc (loc, code, type, imag0, imag1);
13196 if (icond && TREE_CODE (icond) == INTEGER_CST)
13198 if (integer_zerop (icond))
13200 if (code == EQ_EXPR)
13201 return omit_two_operands_loc (loc, type, boolean_false_node,
13203 return fold_build2_loc (loc, NE_EXPR, type, real0, real1);
13207 if (code == NE_EXPR)
13208 return omit_two_operands_loc (loc, type, boolean_true_node,
13210 return fold_build2_loc (loc, EQ_EXPR, type, real0, real1);
13221 tem = fold_comparison (loc, code, type, op0, op1);
13222 if (tem != NULL_TREE)
13225 /* Transform comparisons of the form X +- C CMP X. */
13226 if ((TREE_CODE (arg0) == PLUS_EXPR || TREE_CODE (arg0) == MINUS_EXPR)
13227 && operand_equal_p (TREE_OPERAND (arg0, 0), arg1, 0)
13228 && ((TREE_CODE (TREE_OPERAND (arg0, 1)) == REAL_CST
13229 && !HONOR_SNANS (TYPE_MODE (TREE_TYPE (arg0))))
13230 || (TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST
13231 && TYPE_OVERFLOW_UNDEFINED (TREE_TYPE (arg1)))))
13233 tree arg01 = TREE_OPERAND (arg0, 1);
13234 enum tree_code code0 = TREE_CODE (arg0);
13237 if (TREE_CODE (arg01) == REAL_CST)
13238 is_positive = REAL_VALUE_NEGATIVE (TREE_REAL_CST (arg01)) ? -1 : 1;
13240 is_positive = tree_int_cst_sgn (arg01);
13242 /* (X - c) > X becomes false. */
13243 if (code == GT_EXPR
13244 && ((code0 == MINUS_EXPR && is_positive >= 0)
13245 || (code0 == PLUS_EXPR && is_positive <= 0)))
13247 if (TREE_CODE (arg01) == INTEGER_CST
13248 && TYPE_OVERFLOW_UNDEFINED (TREE_TYPE (arg1)))
13249 fold_overflow_warning (("assuming signed overflow does not "
13250 "occur when assuming that (X - c) > X "
13251 "is always false"),
13252 WARN_STRICT_OVERFLOW_ALL);
13253 return constant_boolean_node (0, type);
13256 /* Likewise (X + c) < X becomes false. */
13257 if (code == LT_EXPR
13258 && ((code0 == PLUS_EXPR && is_positive >= 0)
13259 || (code0 == MINUS_EXPR && is_positive <= 0)))
13261 if (TREE_CODE (arg01) == INTEGER_CST
13262 && TYPE_OVERFLOW_UNDEFINED (TREE_TYPE (arg1)))
13263 fold_overflow_warning (("assuming signed overflow does not "
13264 "occur when assuming that "
13265 "(X + c) < X is always false"),
13266 WARN_STRICT_OVERFLOW_ALL);
13267 return constant_boolean_node (0, type);
13270 /* Convert (X - c) <= X to true. */
13271 if (!HONOR_NANS (TYPE_MODE (TREE_TYPE (arg1)))
13273 && ((code0 == MINUS_EXPR && is_positive >= 0)
13274 || (code0 == PLUS_EXPR && is_positive <= 0)))
13276 if (TREE_CODE (arg01) == INTEGER_CST
13277 && TYPE_OVERFLOW_UNDEFINED (TREE_TYPE (arg1)))
13278 fold_overflow_warning (("assuming signed overflow does not "
13279 "occur when assuming that "
13280 "(X - c) <= X is always true"),
13281 WARN_STRICT_OVERFLOW_ALL);
13282 return constant_boolean_node (1, type);
13285 /* Convert (X + c) >= X to true. */
13286 if (!HONOR_NANS (TYPE_MODE (TREE_TYPE (arg1)))
13288 && ((code0 == PLUS_EXPR && is_positive >= 0)
13289 || (code0 == MINUS_EXPR && is_positive <= 0)))
13291 if (TREE_CODE (arg01) == INTEGER_CST
13292 && TYPE_OVERFLOW_UNDEFINED (TREE_TYPE (arg1)))
13293 fold_overflow_warning (("assuming signed overflow does not "
13294 "occur when assuming that "
13295 "(X + c) >= X is always true"),
13296 WARN_STRICT_OVERFLOW_ALL);
13297 return constant_boolean_node (1, type);
13300 if (TREE_CODE (arg01) == INTEGER_CST)
13302 /* Convert X + c > X and X - c < X to true for integers. */
13303 if (code == GT_EXPR
13304 && ((code0 == PLUS_EXPR && is_positive > 0)
13305 || (code0 == MINUS_EXPR && is_positive < 0)))
13307 if (TYPE_OVERFLOW_UNDEFINED (TREE_TYPE (arg1)))
13308 fold_overflow_warning (("assuming signed overflow does "
13309 "not occur when assuming that "
13310 "(X + c) > X is always true"),
13311 WARN_STRICT_OVERFLOW_ALL);
13312 return constant_boolean_node (1, type);
13315 if (code == LT_EXPR
13316 && ((code0 == MINUS_EXPR && is_positive > 0)
13317 || (code0 == PLUS_EXPR && is_positive < 0)))
13319 if (TYPE_OVERFLOW_UNDEFINED (TREE_TYPE (arg1)))
13320 fold_overflow_warning (("assuming signed overflow does "
13321 "not occur when assuming that "
13322 "(X - c) < X is always true"),
13323 WARN_STRICT_OVERFLOW_ALL);
13324 return constant_boolean_node (1, type);
13327 /* Convert X + c <= X and X - c >= X to false for integers. */
13328 if (code == LE_EXPR
13329 && ((code0 == PLUS_EXPR && is_positive > 0)
13330 || (code0 == MINUS_EXPR && is_positive < 0)))
13332 if (TYPE_OVERFLOW_UNDEFINED (TREE_TYPE (arg1)))
13333 fold_overflow_warning (("assuming signed overflow does "
13334 "not occur when assuming that "
13335 "(X + c) <= X is always false"),
13336 WARN_STRICT_OVERFLOW_ALL);
13337 return constant_boolean_node (0, type);
13340 if (code == GE_EXPR
13341 && ((code0 == MINUS_EXPR && is_positive > 0)
13342 || (code0 == PLUS_EXPR && is_positive < 0)))
13344 if (TYPE_OVERFLOW_UNDEFINED (TREE_TYPE (arg1)))
13345 fold_overflow_warning (("assuming signed overflow does "
13346 "not occur when assuming that "
13347 "(X - c) >= X is always false"),
13348 WARN_STRICT_OVERFLOW_ALL);
13349 return constant_boolean_node (0, type);
13354 /* Comparisons with the highest or lowest possible integer of
13355 the specified precision will have known values. */
13357 tree arg1_type = TREE_TYPE (arg1);
13358 unsigned int width = TYPE_PRECISION (arg1_type);
13360 if (TREE_CODE (arg1) == INTEGER_CST
13361 && width <= 2 * HOST_BITS_PER_WIDE_INT
13362 && (INTEGRAL_TYPE_P (arg1_type) || POINTER_TYPE_P (arg1_type)))
13364 HOST_WIDE_INT signed_max_hi;
13365 unsigned HOST_WIDE_INT signed_max_lo;
13366 unsigned HOST_WIDE_INT max_hi, max_lo, min_hi, min_lo;
13368 if (width <= HOST_BITS_PER_WIDE_INT)
13370 signed_max_lo = ((unsigned HOST_WIDE_INT) 1 << (width - 1))
13375 if (TYPE_UNSIGNED (arg1_type))
13377 max_lo = ((unsigned HOST_WIDE_INT) 2 << (width - 1)) - 1;
13383 max_lo = signed_max_lo;
13384 min_lo = ((unsigned HOST_WIDE_INT) -1 << (width - 1));
13390 width -= HOST_BITS_PER_WIDE_INT;
13391 signed_max_lo = -1;
13392 signed_max_hi = ((unsigned HOST_WIDE_INT) 1 << (width - 1))
13397 if (TYPE_UNSIGNED (arg1_type))
13399 max_hi = ((unsigned HOST_WIDE_INT) 2 << (width - 1)) - 1;
13404 max_hi = signed_max_hi;
13405 min_hi = ((unsigned HOST_WIDE_INT) -1 << (width - 1));
13409 if ((unsigned HOST_WIDE_INT) TREE_INT_CST_HIGH (arg1) == max_hi
13410 && TREE_INT_CST_LOW (arg1) == max_lo)
13414 return omit_one_operand_loc (loc, type, integer_zero_node, arg0);
13417 return fold_build2_loc (loc, EQ_EXPR, type, op0, op1);
13420 return omit_one_operand_loc (loc, type, integer_one_node, arg0);
13423 return fold_build2_loc (loc, NE_EXPR, type, op0, op1);
13425 /* The GE_EXPR and LT_EXPR cases above are not normally
13426 reached because of previous transformations. */
13431 else if ((unsigned HOST_WIDE_INT) TREE_INT_CST_HIGH (arg1)
13433 && TREE_INT_CST_LOW (arg1) == max_lo - 1)
13437 arg1 = const_binop (PLUS_EXPR, arg1,
13438 build_int_cst (TREE_TYPE (arg1), 1), 0);
13439 return fold_build2_loc (loc, EQ_EXPR, type,
13440 fold_convert_loc (loc,
13441 TREE_TYPE (arg1), arg0),
13444 arg1 = const_binop (PLUS_EXPR, arg1,
13445 build_int_cst (TREE_TYPE (arg1), 1), 0);
13446 return fold_build2_loc (loc, NE_EXPR, type,
13447 fold_convert_loc (loc, TREE_TYPE (arg1),
13453 else if ((unsigned HOST_WIDE_INT) TREE_INT_CST_HIGH (arg1)
13455 && TREE_INT_CST_LOW (arg1) == min_lo)
13459 return omit_one_operand_loc (loc, type, integer_zero_node, arg0);
13462 return fold_build2_loc (loc, EQ_EXPR, type, op0, op1);
13465 return omit_one_operand_loc (loc, type, integer_one_node, arg0);
13468 return fold_build2_loc (loc, NE_EXPR, type, op0, op1);
13473 else if ((unsigned HOST_WIDE_INT) TREE_INT_CST_HIGH (arg1)
13475 && TREE_INT_CST_LOW (arg1) == min_lo + 1)
13479 arg1 = const_binop (MINUS_EXPR, arg1, integer_one_node, 0);
13480 return fold_build2_loc (loc, NE_EXPR, type,
13481 fold_convert_loc (loc,
13482 TREE_TYPE (arg1), arg0),
13485 arg1 = const_binop (MINUS_EXPR, arg1, integer_one_node, 0);
13486 return fold_build2_loc (loc, EQ_EXPR, type,
13487 fold_convert_loc (loc, TREE_TYPE (arg1),
13494 else if (TREE_INT_CST_HIGH (arg1) == signed_max_hi
13495 && TREE_INT_CST_LOW (arg1) == signed_max_lo
13496 && TYPE_UNSIGNED (arg1_type)
13497 /* We will flip the signedness of the comparison operator
13498 associated with the mode of arg1, so the sign bit is
13499 specified by this mode. Check that arg1 is the signed
13500 max associated with this sign bit. */
13501 && width == GET_MODE_BITSIZE (TYPE_MODE (arg1_type))
13502 /* signed_type does not work on pointer types. */
13503 && INTEGRAL_TYPE_P (arg1_type))
13505 /* The following case also applies to X < signed_max+1
13506 and X >= signed_max+1 because previous transformations. */
13507 if (code == LE_EXPR || code == GT_EXPR)
13510 st = signed_type_for (TREE_TYPE (arg1));
13511 return fold_build2_loc (loc,
13512 code == LE_EXPR ? GE_EXPR : LT_EXPR,
13513 type, fold_convert_loc (loc, st, arg0),
13514 build_int_cst (st, 0));
13520 /* If we are comparing an ABS_EXPR with a constant, we can
13521 convert all the cases into explicit comparisons, but they may
13522 well not be faster than doing the ABS and one comparison.
13523 But ABS (X) <= C is a range comparison, which becomes a subtraction
13524 and a comparison, and is probably faster. */
13525 if (code == LE_EXPR
13526 && TREE_CODE (arg1) == INTEGER_CST
13527 && TREE_CODE (arg0) == ABS_EXPR
13528 && ! TREE_SIDE_EFFECTS (arg0)
13529 && (0 != (tem = negate_expr (arg1)))
13530 && TREE_CODE (tem) == INTEGER_CST
13531 && !TREE_OVERFLOW (tem))
13532 return fold_build2_loc (loc, TRUTH_ANDIF_EXPR, type,
13533 build2 (GE_EXPR, type,
13534 TREE_OPERAND (arg0, 0), tem),
13535 build2 (LE_EXPR, type,
13536 TREE_OPERAND (arg0, 0), arg1));
13538 /* Convert ABS_EXPR<x> >= 0 to true. */
13539 strict_overflow_p = false;
13540 if (code == GE_EXPR
13541 && (integer_zerop (arg1)
13542 || (! HONOR_NANS (TYPE_MODE (TREE_TYPE (arg0)))
13543 && real_zerop (arg1)))
13544 && tree_expr_nonnegative_warnv_p (arg0, &strict_overflow_p))
13546 if (strict_overflow_p)
13547 fold_overflow_warning (("assuming signed overflow does not occur "
13548 "when simplifying comparison of "
13549 "absolute value and zero"),
13550 WARN_STRICT_OVERFLOW_CONDITIONAL);
13551 return omit_one_operand_loc (loc, type, integer_one_node, arg0);
13554 /* Convert ABS_EXPR<x> < 0 to false. */
13555 strict_overflow_p = false;
13556 if (code == LT_EXPR
13557 && (integer_zerop (arg1) || real_zerop (arg1))
13558 && tree_expr_nonnegative_warnv_p (arg0, &strict_overflow_p))
13560 if (strict_overflow_p)
13561 fold_overflow_warning (("assuming signed overflow does not occur "
13562 "when simplifying comparison of "
13563 "absolute value and zero"),
13564 WARN_STRICT_OVERFLOW_CONDITIONAL);
13565 return omit_one_operand_loc (loc, type, integer_zero_node, arg0);
13568 /* If X is unsigned, convert X < (1 << Y) into X >> Y == 0
13569 and similarly for >= into !=. */
13570 if ((code == LT_EXPR || code == GE_EXPR)
13571 && TYPE_UNSIGNED (TREE_TYPE (arg0))
13572 && TREE_CODE (arg1) == LSHIFT_EXPR
13573 && integer_onep (TREE_OPERAND (arg1, 0)))
13575 tem = build2 (code == LT_EXPR ? EQ_EXPR : NE_EXPR, type,
13576 build2 (RSHIFT_EXPR, TREE_TYPE (arg0), arg0,
13577 TREE_OPERAND (arg1, 1)),
13578 build_int_cst (TREE_TYPE (arg0), 0));
13579 goto fold_binary_exit;
13582 if ((code == LT_EXPR || code == GE_EXPR)
13583 && TYPE_UNSIGNED (TREE_TYPE (arg0))
13584 && CONVERT_EXPR_P (arg1)
13585 && TREE_CODE (TREE_OPERAND (arg1, 0)) == LSHIFT_EXPR
13586 && integer_onep (TREE_OPERAND (TREE_OPERAND (arg1, 0), 0)))
13588 tem = build2 (code == LT_EXPR ? EQ_EXPR : NE_EXPR, type,
13589 fold_convert_loc (loc, TREE_TYPE (arg0),
13590 build2 (RSHIFT_EXPR,
13591 TREE_TYPE (arg0), arg0,
13592 TREE_OPERAND (TREE_OPERAND (arg1, 0),
13594 build_int_cst (TREE_TYPE (arg0), 0));
13595 goto fold_binary_exit;
13600 case UNORDERED_EXPR:
13608 if (TREE_CODE (arg0) == REAL_CST && TREE_CODE (arg1) == REAL_CST)
13610 t1 = fold_relational_const (code, type, arg0, arg1);
13611 if (t1 != NULL_TREE)
13615 /* If the first operand is NaN, the result is constant. */
13616 if (TREE_CODE (arg0) == REAL_CST
13617 && REAL_VALUE_ISNAN (TREE_REAL_CST (arg0))
13618 && (code != LTGT_EXPR || ! flag_trapping_math))
13620 t1 = (code == ORDERED_EXPR || code == LTGT_EXPR)
13621 ? integer_zero_node
13622 : integer_one_node;
13623 return omit_one_operand_loc (loc, type, t1, arg1);
13626 /* If the second operand is NaN, the result is constant. */
13627 if (TREE_CODE (arg1) == REAL_CST
13628 && REAL_VALUE_ISNAN (TREE_REAL_CST (arg1))
13629 && (code != LTGT_EXPR || ! flag_trapping_math))
13631 t1 = (code == ORDERED_EXPR || code == LTGT_EXPR)
13632 ? integer_zero_node
13633 : integer_one_node;
13634 return omit_one_operand_loc (loc, type, t1, arg0);
13637 /* Simplify unordered comparison of something with itself. */
13638 if ((code == UNLE_EXPR || code == UNGE_EXPR || code == UNEQ_EXPR)
13639 && operand_equal_p (arg0, arg1, 0))
13640 return constant_boolean_node (1, type);
13642 if (code == LTGT_EXPR
13643 && !flag_trapping_math
13644 && operand_equal_p (arg0, arg1, 0))
13645 return constant_boolean_node (0, type);
13647 /* Fold (double)float1 CMP (double)float2 into float1 CMP float2. */
13649 tree targ0 = strip_float_extensions (arg0);
13650 tree targ1 = strip_float_extensions (arg1);
13651 tree newtype = TREE_TYPE (targ0);
13653 if (TYPE_PRECISION (TREE_TYPE (targ1)) > TYPE_PRECISION (newtype))
13654 newtype = TREE_TYPE (targ1);
13656 if (TYPE_PRECISION (newtype) < TYPE_PRECISION (TREE_TYPE (arg0)))
13657 return fold_build2_loc (loc, code, type,
13658 fold_convert_loc (loc, newtype, targ0),
13659 fold_convert_loc (loc, newtype, targ1));
13664 case COMPOUND_EXPR:
13665 /* When pedantic, a compound expression can be neither an lvalue
13666 nor an integer constant expression. */
13667 if (TREE_SIDE_EFFECTS (arg0) || TREE_CONSTANT (arg1))
13669 /* Don't let (0, 0) be null pointer constant. */
13670 tem = integer_zerop (arg1) ? build1 (NOP_EXPR, type, arg1)
13671 : fold_convert_loc (loc, type, arg1);
13672 return pedantic_non_lvalue_loc (loc, tem);
13675 if ((TREE_CODE (arg0) == REAL_CST
13676 && TREE_CODE (arg1) == REAL_CST)
13677 || (TREE_CODE (arg0) == INTEGER_CST
13678 && TREE_CODE (arg1) == INTEGER_CST))
13679 return build_complex (type, arg0, arg1);
13683 /* An ASSERT_EXPR should never be passed to fold_binary. */
13684 gcc_unreachable ();
13688 } /* switch (code) */
13690 protected_set_expr_location (tem, loc);
13694 /* Callback for walk_tree, looking for LABEL_EXPR. Return *TP if it is
13695 a LABEL_EXPR; otherwise return NULL_TREE. Do not check the subtrees
13699 contains_label_1 (tree *tp, int *walk_subtrees, void *data ATTRIBUTE_UNUSED)
13701 switch (TREE_CODE (*tp))
13707 *walk_subtrees = 0;
13709 /* ... fall through ... */
13716 /* Return whether the sub-tree ST contains a label which is accessible from
13717 outside the sub-tree. */
13720 contains_label_p (tree st)
13723 (walk_tree_without_duplicates (&st, contains_label_1 , NULL) != NULL_TREE);
13726 /* Fold a ternary expression of code CODE and type TYPE with operands
13727 OP0, OP1, and OP2. Return the folded expression if folding is
13728 successful. Otherwise, return NULL_TREE. */
13731 fold_ternary_loc (location_t loc, enum tree_code code, tree type,
13732 tree op0, tree op1, tree op2)
13735 tree arg0 = NULL_TREE, arg1 = NULL_TREE;
13736 enum tree_code_class kind = TREE_CODE_CLASS (code);
13738 gcc_assert (IS_EXPR_CODE_CLASS (kind)
13739 && TREE_CODE_LENGTH (code) == 3);
13741 /* Strip any conversions that don't change the mode. This is safe
13742 for every expression, except for a comparison expression because
13743 its signedness is derived from its operands. So, in the latter
13744 case, only strip conversions that don't change the signedness.
13746 Note that this is done as an internal manipulation within the
13747 constant folder, in order to find the simplest representation of
13748 the arguments so that their form can be studied. In any cases,
13749 the appropriate type conversions should be put back in the tree
13750 that will get out of the constant folder. */
13765 case COMPONENT_REF:
13766 if (TREE_CODE (arg0) == CONSTRUCTOR
13767 && ! type_contains_placeholder_p (TREE_TYPE (arg0)))
13769 unsigned HOST_WIDE_INT idx;
13771 FOR_EACH_CONSTRUCTOR_ELT (CONSTRUCTOR_ELTS (arg0), idx, field, value)
13778 /* Pedantic ANSI C says that a conditional expression is never an lvalue,
13779 so all simple results must be passed through pedantic_non_lvalue. */
13780 if (TREE_CODE (arg0) == INTEGER_CST)
13782 tree unused_op = integer_zerop (arg0) ? op1 : op2;
13783 tem = integer_zerop (arg0) ? op2 : op1;
13784 /* Only optimize constant conditions when the selected branch
13785 has the same type as the COND_EXPR. This avoids optimizing
13786 away "c ? x : throw", where the throw has a void type.
13787 Avoid throwing away that operand which contains label. */
13788 if ((!TREE_SIDE_EFFECTS (unused_op)
13789 || !contains_label_p (unused_op))
13790 && (! VOID_TYPE_P (TREE_TYPE (tem))
13791 || VOID_TYPE_P (type)))
13792 return pedantic_non_lvalue_loc (loc, tem);
13795 if (operand_equal_p (arg1, op2, 0))
13796 return pedantic_omit_one_operand_loc (loc, type, arg1, arg0);
13798 /* If we have A op B ? A : C, we may be able to convert this to a
13799 simpler expression, depending on the operation and the values
13800 of B and C. Signed zeros prevent all of these transformations,
13801 for reasons given above each one.
13803 Also try swapping the arguments and inverting the conditional. */
13804 if (COMPARISON_CLASS_P (arg0)
13805 && operand_equal_for_comparison_p (TREE_OPERAND (arg0, 0),
13806 arg1, TREE_OPERAND (arg0, 1))
13807 && !HONOR_SIGNED_ZEROS (TYPE_MODE (TREE_TYPE (arg1))))
13809 tem = fold_cond_expr_with_comparison (loc, type, arg0, op1, op2);
13814 if (COMPARISON_CLASS_P (arg0)
13815 && operand_equal_for_comparison_p (TREE_OPERAND (arg0, 0),
13817 TREE_OPERAND (arg0, 1))
13818 && !HONOR_SIGNED_ZEROS (TYPE_MODE (TREE_TYPE (op2))))
13820 tem = fold_truth_not_expr (loc, arg0);
13821 if (tem && COMPARISON_CLASS_P (tem))
13823 tem = fold_cond_expr_with_comparison (loc, type, tem, op2, op1);
13829 /* If the second operand is simpler than the third, swap them
13830 since that produces better jump optimization results. */
13831 if (truth_value_p (TREE_CODE (arg0))
13832 && tree_swap_operands_p (op1, op2, false))
13834 /* See if this can be inverted. If it can't, possibly because
13835 it was a floating-point inequality comparison, don't do
13837 tem = fold_truth_not_expr (loc, arg0);
13839 return fold_build3_loc (loc, code, type, tem, op2, op1);
13842 /* Convert A ? 1 : 0 to simply A. */
13843 if (integer_onep (op1)
13844 && integer_zerop (op2)
13845 /* If we try to convert OP0 to our type, the
13846 call to fold will try to move the conversion inside
13847 a COND, which will recurse. In that case, the COND_EXPR
13848 is probably the best choice, so leave it alone. */
13849 && type == TREE_TYPE (arg0))
13850 return pedantic_non_lvalue_loc (loc, arg0);
13852 /* Convert A ? 0 : 1 to !A. This prefers the use of NOT_EXPR
13853 over COND_EXPR in cases such as floating point comparisons. */
13854 if (integer_zerop (op1)
13855 && integer_onep (op2)
13856 && truth_value_p (TREE_CODE (arg0)))
13857 return pedantic_non_lvalue_loc (loc,
13858 fold_convert_loc (loc, type,
13859 invert_truthvalue_loc (loc,
13862 /* A < 0 ? <sign bit of A> : 0 is simply (A & <sign bit of A>). */
13863 if (TREE_CODE (arg0) == LT_EXPR
13864 && integer_zerop (TREE_OPERAND (arg0, 1))
13865 && integer_zerop (op2)
13866 && (tem = sign_bit_p (TREE_OPERAND (arg0, 0), arg1)))
13868 /* sign_bit_p only checks ARG1 bits within A's precision.
13869 If <sign bit of A> has wider type than A, bits outside
13870 of A's precision in <sign bit of A> need to be checked.
13871 If they are all 0, this optimization needs to be done
13872 in unsigned A's type, if they are all 1 in signed A's type,
13873 otherwise this can't be done. */
13874 if (TYPE_PRECISION (TREE_TYPE (tem))
13875 < TYPE_PRECISION (TREE_TYPE (arg1))
13876 && TYPE_PRECISION (TREE_TYPE (tem))
13877 < TYPE_PRECISION (type))
13879 unsigned HOST_WIDE_INT mask_lo;
13880 HOST_WIDE_INT mask_hi;
13881 int inner_width, outer_width;
13884 inner_width = TYPE_PRECISION (TREE_TYPE (tem));
13885 outer_width = TYPE_PRECISION (TREE_TYPE (arg1));
13886 if (outer_width > TYPE_PRECISION (type))
13887 outer_width = TYPE_PRECISION (type);
13889 if (outer_width > HOST_BITS_PER_WIDE_INT)
13891 mask_hi = ((unsigned HOST_WIDE_INT) -1
13892 >> (2 * HOST_BITS_PER_WIDE_INT - outer_width));
13898 mask_lo = ((unsigned HOST_WIDE_INT) -1
13899 >> (HOST_BITS_PER_WIDE_INT - outer_width));
13901 if (inner_width > HOST_BITS_PER_WIDE_INT)
13903 mask_hi &= ~((unsigned HOST_WIDE_INT) -1
13904 >> (HOST_BITS_PER_WIDE_INT - inner_width));
13908 mask_lo &= ~((unsigned HOST_WIDE_INT) -1
13909 >> (HOST_BITS_PER_WIDE_INT - inner_width));
13911 if ((TREE_INT_CST_HIGH (arg1) & mask_hi) == mask_hi
13912 && (TREE_INT_CST_LOW (arg1) & mask_lo) == mask_lo)
13914 tem_type = signed_type_for (TREE_TYPE (tem));
13915 tem = fold_convert_loc (loc, tem_type, tem);
13917 else if ((TREE_INT_CST_HIGH (arg1) & mask_hi) == 0
13918 && (TREE_INT_CST_LOW (arg1) & mask_lo) == 0)
13920 tem_type = unsigned_type_for (TREE_TYPE (tem));
13921 tem = fold_convert_loc (loc, tem_type, tem);
13929 fold_convert_loc (loc, type,
13930 fold_build2_loc (loc, BIT_AND_EXPR,
13931 TREE_TYPE (tem), tem,
13932 fold_convert_loc (loc,
13937 /* (A >> N) & 1 ? (1 << N) : 0 is simply A & (1 << N). A & 1 was
13938 already handled above. */
13939 if (TREE_CODE (arg0) == BIT_AND_EXPR
13940 && integer_onep (TREE_OPERAND (arg0, 1))
13941 && integer_zerop (op2)
13942 && integer_pow2p (arg1))
13944 tree tem = TREE_OPERAND (arg0, 0);
13946 if (TREE_CODE (tem) == RSHIFT_EXPR
13947 && TREE_CODE (TREE_OPERAND (tem, 1)) == INTEGER_CST
13948 && (unsigned HOST_WIDE_INT) tree_log2 (arg1) ==
13949 TREE_INT_CST_LOW (TREE_OPERAND (tem, 1)))
13950 return fold_build2_loc (loc, BIT_AND_EXPR, type,
13951 TREE_OPERAND (tem, 0), arg1);
13954 /* A & N ? N : 0 is simply A & N if N is a power of two. This
13955 is probably obsolete because the first operand should be a
13956 truth value (that's why we have the two cases above), but let's
13957 leave it in until we can confirm this for all front-ends. */
13958 if (integer_zerop (op2)
13959 && TREE_CODE (arg0) == NE_EXPR
13960 && integer_zerop (TREE_OPERAND (arg0, 1))
13961 && integer_pow2p (arg1)
13962 && TREE_CODE (TREE_OPERAND (arg0, 0)) == BIT_AND_EXPR
13963 && operand_equal_p (TREE_OPERAND (TREE_OPERAND (arg0, 0), 1),
13964 arg1, OEP_ONLY_CONST))
13965 return pedantic_non_lvalue_loc (loc,
13966 fold_convert_loc (loc, type,
13967 TREE_OPERAND (arg0, 0)));
13969 /* Convert A ? B : 0 into A && B if A and B are truth values. */
13970 if (integer_zerop (op2)
13971 && truth_value_p (TREE_CODE (arg0))
13972 && truth_value_p (TREE_CODE (arg1)))
13973 return fold_build2_loc (loc, TRUTH_ANDIF_EXPR, type,
13974 fold_convert_loc (loc, type, arg0),
13977 /* Convert A ? B : 1 into !A || B if A and B are truth values. */
13978 if (integer_onep (op2)
13979 && truth_value_p (TREE_CODE (arg0))
13980 && truth_value_p (TREE_CODE (arg1)))
13982 /* Only perform transformation if ARG0 is easily inverted. */
13983 tem = fold_truth_not_expr (loc, arg0);
13985 return fold_build2_loc (loc, TRUTH_ORIF_EXPR, type,
13986 fold_convert_loc (loc, type, tem),
13990 /* Convert A ? 0 : B into !A && B if A and B are truth values. */
13991 if (integer_zerop (arg1)
13992 && truth_value_p (TREE_CODE (arg0))
13993 && truth_value_p (TREE_CODE (op2)))
13995 /* Only perform transformation if ARG0 is easily inverted. */
13996 tem = fold_truth_not_expr (loc, arg0);
13998 return fold_build2_loc (loc, TRUTH_ANDIF_EXPR, type,
13999 fold_convert_loc (loc, type, tem),
14003 /* Convert A ? 1 : B into A || B if A and B are truth values. */
14004 if (integer_onep (arg1)
14005 && truth_value_p (TREE_CODE (arg0))
14006 && truth_value_p (TREE_CODE (op2)))
14007 return fold_build2_loc (loc, TRUTH_ORIF_EXPR, type,
14008 fold_convert_loc (loc, type, arg0),
14014 /* CALL_EXPRs used to be ternary exprs. Catch any mistaken uses
14015 of fold_ternary on them. */
14016 gcc_unreachable ();
14018 case BIT_FIELD_REF:
14019 if ((TREE_CODE (arg0) == VECTOR_CST
14020 || (TREE_CODE (arg0) == CONSTRUCTOR && TREE_CONSTANT (arg0)))
14021 && type == TREE_TYPE (TREE_TYPE (arg0)))
14023 unsigned HOST_WIDE_INT width = tree_low_cst (arg1, 1);
14024 unsigned HOST_WIDE_INT idx = tree_low_cst (op2, 1);
14027 && simple_cst_equal (arg1, TYPE_SIZE (type)) == 1
14028 && (idx % width) == 0
14029 && (idx = idx / width)
14030 < TYPE_VECTOR_SUBPARTS (TREE_TYPE (arg0)))
14032 tree elements = NULL_TREE;
14034 if (TREE_CODE (arg0) == VECTOR_CST)
14035 elements = TREE_VECTOR_CST_ELTS (arg0);
14038 unsigned HOST_WIDE_INT idx;
14041 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (arg0), idx, value)
14042 elements = tree_cons (NULL_TREE, value, elements);
14044 while (idx-- > 0 && elements)
14045 elements = TREE_CHAIN (elements);
14047 return TREE_VALUE (elements);
14049 return fold_convert_loc (loc, type, integer_zero_node);
14053 /* A bit-field-ref that referenced the full argument can be stripped. */
14054 if (INTEGRAL_TYPE_P (TREE_TYPE (arg0))
14055 && TYPE_PRECISION (TREE_TYPE (arg0)) == tree_low_cst (arg1, 1)
14056 && integer_zerop (op2))
14057 return fold_convert_loc (loc, type, arg0);
14063 } /* switch (code) */
14066 /* Perform constant folding and related simplification of EXPR.
14067 The related simplifications include x*1 => x, x*0 => 0, etc.,
14068 and application of the associative law.
14069 NOP_EXPR conversions may be removed freely (as long as we
14070 are careful not to change the type of the overall expression).
14071 We cannot simplify through a CONVERT_EXPR, FIX_EXPR or FLOAT_EXPR,
14072 but we can constant-fold them if they have constant operands. */
14074 #ifdef ENABLE_FOLD_CHECKING
14075 # define fold(x) fold_1 (x)
14076 static tree fold_1 (tree);
14082 const tree t = expr;
14083 enum tree_code code = TREE_CODE (t);
14084 enum tree_code_class kind = TREE_CODE_CLASS (code);
14086 location_t loc = EXPR_LOCATION (expr);
14088 /* Return right away if a constant. */
14089 if (kind == tcc_constant)
14092 /* CALL_EXPR-like objects with variable numbers of operands are
14093 treated specially. */
14094 if (kind == tcc_vl_exp)
14096 if (code == CALL_EXPR)
14098 tem = fold_call_expr (loc, expr, false);
14099 return tem ? tem : expr;
14104 if (IS_EXPR_CODE_CLASS (kind))
14106 tree type = TREE_TYPE (t);
14107 tree op0, op1, op2;
14109 switch (TREE_CODE_LENGTH (code))
14112 op0 = TREE_OPERAND (t, 0);
14113 tem = fold_unary_loc (loc, code, type, op0);
14114 return tem ? tem : expr;
14116 op0 = TREE_OPERAND (t, 0);
14117 op1 = TREE_OPERAND (t, 1);
14118 tem = fold_binary_loc (loc, code, type, op0, op1);
14119 return tem ? tem : expr;
14121 op0 = TREE_OPERAND (t, 0);
14122 op1 = TREE_OPERAND (t, 1);
14123 op2 = TREE_OPERAND (t, 2);
14124 tem = fold_ternary_loc (loc, code, type, op0, op1, op2);
14125 return tem ? tem : expr;
14135 tree op0 = TREE_OPERAND (t, 0);
14136 tree op1 = TREE_OPERAND (t, 1);
14138 if (TREE_CODE (op1) == INTEGER_CST
14139 && TREE_CODE (op0) == CONSTRUCTOR
14140 && ! type_contains_placeholder_p (TREE_TYPE (op0)))
14142 VEC(constructor_elt,gc) *elts = CONSTRUCTOR_ELTS (op0);
14143 unsigned HOST_WIDE_INT end = VEC_length (constructor_elt, elts);
14144 unsigned HOST_WIDE_INT begin = 0;
14146 /* Find a matching index by means of a binary search. */
14147 while (begin != end)
14149 unsigned HOST_WIDE_INT middle = (begin + end) / 2;
14150 tree index = VEC_index (constructor_elt, elts, middle)->index;
14152 if (TREE_CODE (index) == INTEGER_CST
14153 && tree_int_cst_lt (index, op1))
14154 begin = middle + 1;
14155 else if (TREE_CODE (index) == INTEGER_CST
14156 && tree_int_cst_lt (op1, index))
14158 else if (TREE_CODE (index) == RANGE_EXPR
14159 && tree_int_cst_lt (TREE_OPERAND (index, 1), op1))
14160 begin = middle + 1;
14161 else if (TREE_CODE (index) == RANGE_EXPR
14162 && tree_int_cst_lt (op1, TREE_OPERAND (index, 0)))
14165 return VEC_index (constructor_elt, elts, middle)->value;
14173 return fold (DECL_INITIAL (t));
14177 } /* switch (code) */
14180 #ifdef ENABLE_FOLD_CHECKING
14183 static void fold_checksum_tree (const_tree, struct md5_ctx *, htab_t);
14184 static void fold_check_failed (const_tree, const_tree);
14185 void print_fold_checksum (const_tree);
14187 /* When --enable-checking=fold, compute a digest of expr before
14188 and after actual fold call to see if fold did not accidentally
14189 change original expr. */
14195 struct md5_ctx ctx;
14196 unsigned char checksum_before[16], checksum_after[16];
14199 ht = htab_create (32, htab_hash_pointer, htab_eq_pointer, NULL);
14200 md5_init_ctx (&ctx);
14201 fold_checksum_tree (expr, &ctx, ht);
14202 md5_finish_ctx (&ctx, checksum_before);
14205 ret = fold_1 (expr);
14207 md5_init_ctx (&ctx);
14208 fold_checksum_tree (expr, &ctx, ht);
14209 md5_finish_ctx (&ctx, checksum_after);
14212 if (memcmp (checksum_before, checksum_after, 16))
14213 fold_check_failed (expr, ret);
14219 print_fold_checksum (const_tree expr)
14221 struct md5_ctx ctx;
14222 unsigned char checksum[16], cnt;
14225 ht = htab_create (32, htab_hash_pointer, htab_eq_pointer, NULL);
14226 md5_init_ctx (&ctx);
14227 fold_checksum_tree (expr, &ctx, ht);
14228 md5_finish_ctx (&ctx, checksum);
14230 for (cnt = 0; cnt < 16; ++cnt)
14231 fprintf (stderr, "%02x", checksum[cnt]);
14232 putc ('\n', stderr);
14236 fold_check_failed (const_tree expr ATTRIBUTE_UNUSED, const_tree ret ATTRIBUTE_UNUSED)
14238 internal_error ("fold check: original tree changed by fold");
14242 fold_checksum_tree (const_tree expr, struct md5_ctx *ctx, htab_t ht)
14245 enum tree_code code;
14246 union tree_node buf;
14251 gcc_assert ((sizeof (struct tree_exp) + 5 * sizeof (tree)
14252 <= sizeof (struct tree_function_decl))
14253 && sizeof (struct tree_type) <= sizeof (struct tree_function_decl));
14256 slot = (const void **) htab_find_slot (ht, expr, INSERT);
14260 code = TREE_CODE (expr);
14261 if (TREE_CODE_CLASS (code) == tcc_declaration
14262 && DECL_ASSEMBLER_NAME_SET_P (expr))
14264 /* Allow DECL_ASSEMBLER_NAME to be modified. */
14265 memcpy ((char *) &buf, expr, tree_size (expr));
14266 SET_DECL_ASSEMBLER_NAME ((tree)&buf, NULL);
14267 expr = (tree) &buf;
14269 else if (TREE_CODE_CLASS (code) == tcc_type
14270 && (TYPE_POINTER_TO (expr)
14271 || TYPE_REFERENCE_TO (expr)
14272 || TYPE_CACHED_VALUES_P (expr)
14273 || TYPE_CONTAINS_PLACEHOLDER_INTERNAL (expr)
14274 || TYPE_NEXT_VARIANT (expr)))
14276 /* Allow these fields to be modified. */
14278 memcpy ((char *) &buf, expr, tree_size (expr));
14279 expr = tmp = (tree) &buf;
14280 TYPE_CONTAINS_PLACEHOLDER_INTERNAL (tmp) = 0;
14281 TYPE_POINTER_TO (tmp) = NULL;
14282 TYPE_REFERENCE_TO (tmp) = NULL;
14283 TYPE_NEXT_VARIANT (tmp) = NULL;
14284 if (TYPE_CACHED_VALUES_P (tmp))
14286 TYPE_CACHED_VALUES_P (tmp) = 0;
14287 TYPE_CACHED_VALUES (tmp) = NULL;
14290 md5_process_bytes (expr, tree_size (expr), ctx);
14291 fold_checksum_tree (TREE_TYPE (expr), ctx, ht);
14292 if (TREE_CODE_CLASS (code) != tcc_type
14293 && TREE_CODE_CLASS (code) != tcc_declaration
14294 && code != TREE_LIST
14295 && code != SSA_NAME)
14296 fold_checksum_tree (TREE_CHAIN (expr), ctx, ht);
14297 switch (TREE_CODE_CLASS (code))
14303 md5_process_bytes (TREE_STRING_POINTER (expr),
14304 TREE_STRING_LENGTH (expr), ctx);
14307 fold_checksum_tree (TREE_REALPART (expr), ctx, ht);
14308 fold_checksum_tree (TREE_IMAGPART (expr), ctx, ht);
14311 fold_checksum_tree (TREE_VECTOR_CST_ELTS (expr), ctx, ht);
14317 case tcc_exceptional:
14321 fold_checksum_tree (TREE_PURPOSE (expr), ctx, ht);
14322 fold_checksum_tree (TREE_VALUE (expr), ctx, ht);
14323 expr = TREE_CHAIN (expr);
14324 goto recursive_label;
14327 for (i = 0; i < TREE_VEC_LENGTH (expr); ++i)
14328 fold_checksum_tree (TREE_VEC_ELT (expr, i), ctx, ht);
14334 case tcc_expression:
14335 case tcc_reference:
14336 case tcc_comparison:
14339 case tcc_statement:
14341 len = TREE_OPERAND_LENGTH (expr);
14342 for (i = 0; i < len; ++i)
14343 fold_checksum_tree (TREE_OPERAND (expr, i), ctx, ht);
14345 case tcc_declaration:
14346 fold_checksum_tree (DECL_NAME (expr), ctx, ht);
14347 fold_checksum_tree (DECL_CONTEXT (expr), ctx, ht);
14348 if (CODE_CONTAINS_STRUCT (TREE_CODE (expr), TS_DECL_COMMON))
14350 fold_checksum_tree (DECL_SIZE (expr), ctx, ht);
14351 fold_checksum_tree (DECL_SIZE_UNIT (expr), ctx, ht);
14352 fold_checksum_tree (DECL_INITIAL (expr), ctx, ht);
14353 fold_checksum_tree (DECL_ABSTRACT_ORIGIN (expr), ctx, ht);
14354 fold_checksum_tree (DECL_ATTRIBUTES (expr), ctx, ht);
14356 if (CODE_CONTAINS_STRUCT (TREE_CODE (expr), TS_DECL_WITH_VIS))
14357 fold_checksum_tree (DECL_SECTION_NAME (expr), ctx, ht);
14359 if (CODE_CONTAINS_STRUCT (TREE_CODE (expr), TS_DECL_NON_COMMON))
14361 fold_checksum_tree (DECL_VINDEX (expr), ctx, ht);
14362 fold_checksum_tree (DECL_RESULT_FLD (expr), ctx, ht);
14363 fold_checksum_tree (DECL_ARGUMENT_FLD (expr), ctx, ht);
14367 if (TREE_CODE (expr) == ENUMERAL_TYPE)
14368 fold_checksum_tree (TYPE_VALUES (expr), ctx, ht);
14369 fold_checksum_tree (TYPE_SIZE (expr), ctx, ht);
14370 fold_checksum_tree (TYPE_SIZE_UNIT (expr), ctx, ht);
14371 fold_checksum_tree (TYPE_ATTRIBUTES (expr), ctx, ht);
14372 fold_checksum_tree (TYPE_NAME (expr), ctx, ht);
14373 if (INTEGRAL_TYPE_P (expr)
14374 || SCALAR_FLOAT_TYPE_P (expr))
14376 fold_checksum_tree (TYPE_MIN_VALUE (expr), ctx, ht);
14377 fold_checksum_tree (TYPE_MAX_VALUE (expr), ctx, ht);
14379 fold_checksum_tree (TYPE_MAIN_VARIANT (expr), ctx, ht);
14380 if (TREE_CODE (expr) == RECORD_TYPE
14381 || TREE_CODE (expr) == UNION_TYPE
14382 || TREE_CODE (expr) == QUAL_UNION_TYPE)
14383 fold_checksum_tree (TYPE_BINFO (expr), ctx, ht);
14384 fold_checksum_tree (TYPE_CONTEXT (expr), ctx, ht);
14391 /* Helper function for outputting the checksum of a tree T. When
14392 debugging with gdb, you can "define mynext" to be "next" followed
14393 by "call debug_fold_checksum (op0)", then just trace down till the
14397 debug_fold_checksum (const_tree t)
14400 unsigned char checksum[16];
14401 struct md5_ctx ctx;
14402 htab_t ht = htab_create (32, htab_hash_pointer, htab_eq_pointer, NULL);
14404 md5_init_ctx (&ctx);
14405 fold_checksum_tree (t, &ctx, ht);
14406 md5_finish_ctx (&ctx, checksum);
14409 for (i = 0; i < 16; i++)
14410 fprintf (stderr, "%d ", checksum[i]);
14412 fprintf (stderr, "\n");
14417 /* Fold a unary tree expression with code CODE of type TYPE with an
14418 operand OP0. LOC is the location of the resulting expression.
14419 Return a folded expression if successful. Otherwise, return a tree
14420 expression with code CODE of type TYPE with an operand OP0. */
14423 fold_build1_stat_loc (location_t loc,
14424 enum tree_code code, tree type, tree op0 MEM_STAT_DECL)
14427 #ifdef ENABLE_FOLD_CHECKING
14428 unsigned char checksum_before[16], checksum_after[16];
14429 struct md5_ctx ctx;
14432 ht = htab_create (32, htab_hash_pointer, htab_eq_pointer, NULL);
14433 md5_init_ctx (&ctx);
14434 fold_checksum_tree (op0, &ctx, ht);
14435 md5_finish_ctx (&ctx, checksum_before);
14439 tem = fold_unary_loc (loc, code, type, op0);
14442 tem = build1_stat (code, type, op0 PASS_MEM_STAT);
14443 SET_EXPR_LOCATION (tem, loc);
14446 #ifdef ENABLE_FOLD_CHECKING
14447 md5_init_ctx (&ctx);
14448 fold_checksum_tree (op0, &ctx, ht);
14449 md5_finish_ctx (&ctx, checksum_after);
14452 if (memcmp (checksum_before, checksum_after, 16))
14453 fold_check_failed (op0, tem);
14458 /* Fold a binary tree expression with code CODE of type TYPE with
14459 operands OP0 and OP1. LOC is the location of the resulting
14460 expression. Return a folded expression if successful. Otherwise,
14461 return a tree expression with code CODE of type TYPE with operands
14465 fold_build2_stat_loc (location_t loc,
14466 enum tree_code code, tree type, tree op0, tree op1
14470 #ifdef ENABLE_FOLD_CHECKING
14471 unsigned char checksum_before_op0[16],
14472 checksum_before_op1[16],
14473 checksum_after_op0[16],
14474 checksum_after_op1[16];
14475 struct md5_ctx ctx;
14478 ht = htab_create (32, htab_hash_pointer, htab_eq_pointer, NULL);
14479 md5_init_ctx (&ctx);
14480 fold_checksum_tree (op0, &ctx, ht);
14481 md5_finish_ctx (&ctx, checksum_before_op0);
14484 md5_init_ctx (&ctx);
14485 fold_checksum_tree (op1, &ctx, ht);
14486 md5_finish_ctx (&ctx, checksum_before_op1);
14490 tem = fold_binary_loc (loc, code, type, op0, op1);
14493 tem = build2_stat (code, type, op0, op1 PASS_MEM_STAT);
14494 SET_EXPR_LOCATION (tem, loc);
14497 #ifdef ENABLE_FOLD_CHECKING
14498 md5_init_ctx (&ctx);
14499 fold_checksum_tree (op0, &ctx, ht);
14500 md5_finish_ctx (&ctx, checksum_after_op0);
14503 if (memcmp (checksum_before_op0, checksum_after_op0, 16))
14504 fold_check_failed (op0, tem);
14506 md5_init_ctx (&ctx);
14507 fold_checksum_tree (op1, &ctx, ht);
14508 md5_finish_ctx (&ctx, checksum_after_op1);
14511 if (memcmp (checksum_before_op1, checksum_after_op1, 16))
14512 fold_check_failed (op1, tem);
14517 /* Fold a ternary tree expression with code CODE of type TYPE with
14518 operands OP0, OP1, and OP2. Return a folded expression if
14519 successful. Otherwise, return a tree expression with code CODE of
14520 type TYPE with operands OP0, OP1, and OP2. */
14523 fold_build3_stat_loc (location_t loc, enum tree_code code, tree type,
14524 tree op0, tree op1, tree op2 MEM_STAT_DECL)
14527 #ifdef ENABLE_FOLD_CHECKING
14528 unsigned char checksum_before_op0[16],
14529 checksum_before_op1[16],
14530 checksum_before_op2[16],
14531 checksum_after_op0[16],
14532 checksum_after_op1[16],
14533 checksum_after_op2[16];
14534 struct md5_ctx ctx;
14537 ht = htab_create (32, htab_hash_pointer, htab_eq_pointer, NULL);
14538 md5_init_ctx (&ctx);
14539 fold_checksum_tree (op0, &ctx, ht);
14540 md5_finish_ctx (&ctx, checksum_before_op0);
14543 md5_init_ctx (&ctx);
14544 fold_checksum_tree (op1, &ctx, ht);
14545 md5_finish_ctx (&ctx, checksum_before_op1);
14548 md5_init_ctx (&ctx);
14549 fold_checksum_tree (op2, &ctx, ht);
14550 md5_finish_ctx (&ctx, checksum_before_op2);
14554 gcc_assert (TREE_CODE_CLASS (code) != tcc_vl_exp);
14555 tem = fold_ternary_loc (loc, code, type, op0, op1, op2);
14558 tem = build3_stat (code, type, op0, op1, op2 PASS_MEM_STAT);
14559 SET_EXPR_LOCATION (tem, loc);
14562 #ifdef ENABLE_FOLD_CHECKING
14563 md5_init_ctx (&ctx);
14564 fold_checksum_tree (op0, &ctx, ht);
14565 md5_finish_ctx (&ctx, checksum_after_op0);
14568 if (memcmp (checksum_before_op0, checksum_after_op0, 16))
14569 fold_check_failed (op0, tem);
14571 md5_init_ctx (&ctx);
14572 fold_checksum_tree (op1, &ctx, ht);
14573 md5_finish_ctx (&ctx, checksum_after_op1);
14576 if (memcmp (checksum_before_op1, checksum_after_op1, 16))
14577 fold_check_failed (op1, tem);
14579 md5_init_ctx (&ctx);
14580 fold_checksum_tree (op2, &ctx, ht);
14581 md5_finish_ctx (&ctx, checksum_after_op2);
14584 if (memcmp (checksum_before_op2, checksum_after_op2, 16))
14585 fold_check_failed (op2, tem);
14590 /* Fold a CALL_EXPR expression of type TYPE with operands FN and NARGS
14591 arguments in ARGARRAY, and a null static chain.
14592 Return a folded expression if successful. Otherwise, return a CALL_EXPR
14593 of type TYPE from the given operands as constructed by build_call_array. */
14596 fold_build_call_array_loc (location_t loc, tree type, tree fn,
14597 int nargs, tree *argarray)
14600 #ifdef ENABLE_FOLD_CHECKING
14601 unsigned char checksum_before_fn[16],
14602 checksum_before_arglist[16],
14603 checksum_after_fn[16],
14604 checksum_after_arglist[16];
14605 struct md5_ctx ctx;
14609 ht = htab_create (32, htab_hash_pointer, htab_eq_pointer, NULL);
14610 md5_init_ctx (&ctx);
14611 fold_checksum_tree (fn, &ctx, ht);
14612 md5_finish_ctx (&ctx, checksum_before_fn);
14615 md5_init_ctx (&ctx);
14616 for (i = 0; i < nargs; i++)
14617 fold_checksum_tree (argarray[i], &ctx, ht);
14618 md5_finish_ctx (&ctx, checksum_before_arglist);
14622 tem = fold_builtin_call_array (loc, type, fn, nargs, argarray);
14624 #ifdef ENABLE_FOLD_CHECKING
14625 md5_init_ctx (&ctx);
14626 fold_checksum_tree (fn, &ctx, ht);
14627 md5_finish_ctx (&ctx, checksum_after_fn);
14630 if (memcmp (checksum_before_fn, checksum_after_fn, 16))
14631 fold_check_failed (fn, tem);
14633 md5_init_ctx (&ctx);
14634 for (i = 0; i < nargs; i++)
14635 fold_checksum_tree (argarray[i], &ctx, ht);
14636 md5_finish_ctx (&ctx, checksum_after_arglist);
14639 if (memcmp (checksum_before_arglist, checksum_after_arglist, 16))
14640 fold_check_failed (NULL_TREE, tem);
14645 /* Perform constant folding and related simplification of initializer
14646 expression EXPR. These behave identically to "fold_buildN" but ignore
14647 potential run-time traps and exceptions that fold must preserve. */
14649 #define START_FOLD_INIT \
14650 int saved_signaling_nans = flag_signaling_nans;\
14651 int saved_trapping_math = flag_trapping_math;\
14652 int saved_rounding_math = flag_rounding_math;\
14653 int saved_trapv = flag_trapv;\
14654 int saved_folding_initializer = folding_initializer;\
14655 flag_signaling_nans = 0;\
14656 flag_trapping_math = 0;\
14657 flag_rounding_math = 0;\
14659 folding_initializer = 1;
14661 #define END_FOLD_INIT \
14662 flag_signaling_nans = saved_signaling_nans;\
14663 flag_trapping_math = saved_trapping_math;\
14664 flag_rounding_math = saved_rounding_math;\
14665 flag_trapv = saved_trapv;\
14666 folding_initializer = saved_folding_initializer;
14669 fold_build1_initializer_loc (location_t loc, enum tree_code code,
14670 tree type, tree op)
14675 result = fold_build1_loc (loc, code, type, op);
14682 fold_build2_initializer_loc (location_t loc, enum tree_code code,
14683 tree type, tree op0, tree op1)
14688 result = fold_build2_loc (loc, code, type, op0, op1);
14695 fold_build3_initializer_loc (location_t loc, enum tree_code code,
14696 tree type, tree op0, tree op1, tree op2)
14701 result = fold_build3_loc (loc, code, type, op0, op1, op2);
14708 fold_build_call_array_initializer_loc (location_t loc, tree type, tree fn,
14709 int nargs, tree *argarray)
14714 result = fold_build_call_array_loc (loc, type, fn, nargs, argarray);
14720 #undef START_FOLD_INIT
14721 #undef END_FOLD_INIT
14723 /* Determine if first argument is a multiple of second argument. Return 0 if
14724 it is not, or we cannot easily determined it to be.
14726 An example of the sort of thing we care about (at this point; this routine
14727 could surely be made more general, and expanded to do what the *_DIV_EXPR's
14728 fold cases do now) is discovering that
14730 SAVE_EXPR (I) * SAVE_EXPR (J * 8)
14736 when we know that the two SAVE_EXPR (J * 8) nodes are the same node.
14738 This code also handles discovering that
14740 SAVE_EXPR (I) * SAVE_EXPR (J * 8)
14742 is a multiple of 8 so we don't have to worry about dealing with a
14743 possible remainder.
14745 Note that we *look* inside a SAVE_EXPR only to determine how it was
14746 calculated; it is not safe for fold to do much of anything else with the
14747 internals of a SAVE_EXPR, since it cannot know when it will be evaluated
14748 at run time. For example, the latter example above *cannot* be implemented
14749 as SAVE_EXPR (I) * J or any variant thereof, since the value of J at
14750 evaluation time of the original SAVE_EXPR is not necessarily the same at
14751 the time the new expression is evaluated. The only optimization of this
14752 sort that would be valid is changing
14754 SAVE_EXPR (I) * SAVE_EXPR (SAVE_EXPR (J) * 8)
14758 SAVE_EXPR (I) * SAVE_EXPR (J)
14760 (where the same SAVE_EXPR (J) is used in the original and the
14761 transformed version). */
14764 multiple_of_p (tree type, const_tree top, const_tree bottom)
14766 if (operand_equal_p (top, bottom, 0))
14769 if (TREE_CODE (type) != INTEGER_TYPE)
14772 switch (TREE_CODE (top))
14775 /* Bitwise and provides a power of two multiple. If the mask is
14776 a multiple of BOTTOM then TOP is a multiple of BOTTOM. */
14777 if (!integer_pow2p (bottom))
14782 return (multiple_of_p (type, TREE_OPERAND (top, 0), bottom)
14783 || multiple_of_p (type, TREE_OPERAND (top, 1), bottom));
14787 return (multiple_of_p (type, TREE_OPERAND (top, 0), bottom)
14788 && multiple_of_p (type, TREE_OPERAND (top, 1), bottom));
14791 if (TREE_CODE (TREE_OPERAND (top, 1)) == INTEGER_CST)
14795 op1 = TREE_OPERAND (top, 1);
14796 /* const_binop may not detect overflow correctly,
14797 so check for it explicitly here. */
14798 if (TYPE_PRECISION (TREE_TYPE (size_one_node))
14799 > TREE_INT_CST_LOW (op1)
14800 && TREE_INT_CST_HIGH (op1) == 0
14801 && 0 != (t1 = fold_convert (type,
14802 const_binop (LSHIFT_EXPR,
14805 && !TREE_OVERFLOW (t1))
14806 return multiple_of_p (type, t1, bottom);
14811 /* Can't handle conversions from non-integral or wider integral type. */
14812 if ((TREE_CODE (TREE_TYPE (TREE_OPERAND (top, 0))) != INTEGER_TYPE)
14813 || (TYPE_PRECISION (type)
14814 < TYPE_PRECISION (TREE_TYPE (TREE_OPERAND (top, 0)))))
14817 /* .. fall through ... */
14820 return multiple_of_p (type, TREE_OPERAND (top, 0), bottom);
14823 if (TREE_CODE (bottom) != INTEGER_CST
14824 || integer_zerop (bottom)
14825 || (TYPE_UNSIGNED (type)
14826 && (tree_int_cst_sgn (top) < 0
14827 || tree_int_cst_sgn (bottom) < 0)))
14829 return integer_zerop (int_const_binop (TRUNC_MOD_EXPR,
14837 /* Return true if CODE or TYPE is known to be non-negative. */
14840 tree_simple_nonnegative_warnv_p (enum tree_code code, tree type)
14842 if ((TYPE_PRECISION (type) != 1 || TYPE_UNSIGNED (type))
14843 && truth_value_p (code))
14844 /* Truth values evaluate to 0 or 1, which is nonnegative unless we
14845 have a signed:1 type (where the value is -1 and 0). */
14850 /* Return true if (CODE OP0) is known to be non-negative. If the return
14851 value is based on the assumption that signed overflow is undefined,
14852 set *STRICT_OVERFLOW_P to true; otherwise, don't change
14853 *STRICT_OVERFLOW_P. */
14856 tree_unary_nonnegative_warnv_p (enum tree_code code, tree type, tree op0,
14857 bool *strict_overflow_p)
14859 if (TYPE_UNSIGNED (type))
14865 /* We can't return 1 if flag_wrapv is set because
14866 ABS_EXPR<INT_MIN> = INT_MIN. */
14867 if (!INTEGRAL_TYPE_P (type))
14869 if (TYPE_OVERFLOW_UNDEFINED (type))
14871 *strict_overflow_p = true;
14876 case NON_LVALUE_EXPR:
14878 case FIX_TRUNC_EXPR:
14879 return tree_expr_nonnegative_warnv_p (op0,
14880 strict_overflow_p);
14884 tree inner_type = TREE_TYPE (op0);
14885 tree outer_type = type;
14887 if (TREE_CODE (outer_type) == REAL_TYPE)
14889 if (TREE_CODE (inner_type) == REAL_TYPE)
14890 return tree_expr_nonnegative_warnv_p (op0,
14891 strict_overflow_p);
14892 if (TREE_CODE (inner_type) == INTEGER_TYPE)
14894 if (TYPE_UNSIGNED (inner_type))
14896 return tree_expr_nonnegative_warnv_p (op0,
14897 strict_overflow_p);
14900 else if (TREE_CODE (outer_type) == INTEGER_TYPE)
14902 if (TREE_CODE (inner_type) == REAL_TYPE)
14903 return tree_expr_nonnegative_warnv_p (op0,
14904 strict_overflow_p);
14905 if (TREE_CODE (inner_type) == INTEGER_TYPE)
14906 return TYPE_PRECISION (inner_type) < TYPE_PRECISION (outer_type)
14907 && TYPE_UNSIGNED (inner_type);
14913 return tree_simple_nonnegative_warnv_p (code, type);
14916 /* We don't know sign of `t', so be conservative and return false. */
14920 /* Return true if (CODE OP0 OP1) is known to be non-negative. If the return
14921 value is based on the assumption that signed overflow is undefined,
14922 set *STRICT_OVERFLOW_P to true; otherwise, don't change
14923 *STRICT_OVERFLOW_P. */
14926 tree_binary_nonnegative_warnv_p (enum tree_code code, tree type, tree op0,
14927 tree op1, bool *strict_overflow_p)
14929 if (TYPE_UNSIGNED (type))
14934 case POINTER_PLUS_EXPR:
14936 if (FLOAT_TYPE_P (type))
14937 return (tree_expr_nonnegative_warnv_p (op0,
14939 && tree_expr_nonnegative_warnv_p (op1,
14940 strict_overflow_p));
14942 /* zero_extend(x) + zero_extend(y) is non-negative if x and y are
14943 both unsigned and at least 2 bits shorter than the result. */
14944 if (TREE_CODE (type) == INTEGER_TYPE
14945 && TREE_CODE (op0) == NOP_EXPR
14946 && TREE_CODE (op1) == NOP_EXPR)
14948 tree inner1 = TREE_TYPE (TREE_OPERAND (op0, 0));
14949 tree inner2 = TREE_TYPE (TREE_OPERAND (op1, 0));
14950 if (TREE_CODE (inner1) == INTEGER_TYPE && TYPE_UNSIGNED (inner1)
14951 && TREE_CODE (inner2) == INTEGER_TYPE && TYPE_UNSIGNED (inner2))
14953 unsigned int prec = MAX (TYPE_PRECISION (inner1),
14954 TYPE_PRECISION (inner2)) + 1;
14955 return prec < TYPE_PRECISION (type);
14961 if (FLOAT_TYPE_P (type))
14963 /* x * x for floating point x is always non-negative. */
14964 if (operand_equal_p (op0, op1, 0))
14966 return (tree_expr_nonnegative_warnv_p (op0,
14968 && tree_expr_nonnegative_warnv_p (op1,
14969 strict_overflow_p));
14972 /* zero_extend(x) * zero_extend(y) is non-negative if x and y are
14973 both unsigned and their total bits is shorter than the result. */
14974 if (TREE_CODE (type) == INTEGER_TYPE
14975 && (TREE_CODE (op0) == NOP_EXPR || TREE_CODE (op0) == INTEGER_CST)
14976 && (TREE_CODE (op1) == NOP_EXPR || TREE_CODE (op1) == INTEGER_CST))
14978 tree inner0 = (TREE_CODE (op0) == NOP_EXPR)
14979 ? TREE_TYPE (TREE_OPERAND (op0, 0))
14981 tree inner1 = (TREE_CODE (op1) == NOP_EXPR)
14982 ? TREE_TYPE (TREE_OPERAND (op1, 0))
14985 bool unsigned0 = TYPE_UNSIGNED (inner0);
14986 bool unsigned1 = TYPE_UNSIGNED (inner1);
14988 if (TREE_CODE (op0) == INTEGER_CST)
14989 unsigned0 = unsigned0 || tree_int_cst_sgn (op0) >= 0;
14991 if (TREE_CODE (op1) == INTEGER_CST)
14992 unsigned1 = unsigned1 || tree_int_cst_sgn (op1) >= 0;
14994 if (TREE_CODE (inner0) == INTEGER_TYPE && unsigned0
14995 && TREE_CODE (inner1) == INTEGER_TYPE && unsigned1)
14997 unsigned int precision0 = (TREE_CODE (op0) == INTEGER_CST)
14998 ? tree_int_cst_min_precision (op0, /*unsignedp=*/true)
14999 : TYPE_PRECISION (inner0);
15001 unsigned int precision1 = (TREE_CODE (op1) == INTEGER_CST)
15002 ? tree_int_cst_min_precision (op1, /*unsignedp=*/true)
15003 : TYPE_PRECISION (inner1);
15005 return precision0 + precision1 < TYPE_PRECISION (type);
15012 return (tree_expr_nonnegative_warnv_p (op0,
15014 || tree_expr_nonnegative_warnv_p (op1,
15015 strict_overflow_p));
15021 case TRUNC_DIV_EXPR:
15022 case CEIL_DIV_EXPR:
15023 case FLOOR_DIV_EXPR:
15024 case ROUND_DIV_EXPR:
15025 return (tree_expr_nonnegative_warnv_p (op0,
15027 && tree_expr_nonnegative_warnv_p (op1,
15028 strict_overflow_p));
15030 case TRUNC_MOD_EXPR:
15031 case CEIL_MOD_EXPR:
15032 case FLOOR_MOD_EXPR:
15033 case ROUND_MOD_EXPR:
15034 return tree_expr_nonnegative_warnv_p (op0,
15035 strict_overflow_p);
15037 return tree_simple_nonnegative_warnv_p (code, type);
15040 /* We don't know sign of `t', so be conservative and return false. */
15044 /* Return true if T is known to be non-negative. If the return
15045 value is based on the assumption that signed overflow is undefined,
15046 set *STRICT_OVERFLOW_P to true; otherwise, don't change
15047 *STRICT_OVERFLOW_P. */
15050 tree_single_nonnegative_warnv_p (tree t, bool *strict_overflow_p)
15052 if (TYPE_UNSIGNED (TREE_TYPE (t)))
15055 switch (TREE_CODE (t))
15058 return tree_int_cst_sgn (t) >= 0;
15061 return ! REAL_VALUE_NEGATIVE (TREE_REAL_CST (t));
15064 return ! FIXED_VALUE_NEGATIVE (TREE_FIXED_CST (t));
15067 return (tree_expr_nonnegative_warnv_p (TREE_OPERAND (t, 1),
15069 && tree_expr_nonnegative_warnv_p (TREE_OPERAND (t, 2),
15070 strict_overflow_p));
15072 return tree_simple_nonnegative_warnv_p (TREE_CODE (t),
15075 /* We don't know sign of `t', so be conservative and return false. */
15079 /* Return true if T is known to be non-negative. If the return
15080 value is based on the assumption that signed overflow is undefined,
15081 set *STRICT_OVERFLOW_P to true; otherwise, don't change
15082 *STRICT_OVERFLOW_P. */
15085 tree_call_nonnegative_warnv_p (tree type, tree fndecl,
15086 tree arg0, tree arg1, bool *strict_overflow_p)
15088 if (fndecl && DECL_BUILT_IN_CLASS (fndecl) == BUILT_IN_NORMAL)
15089 switch (DECL_FUNCTION_CODE (fndecl))
15091 CASE_FLT_FN (BUILT_IN_ACOS):
15092 CASE_FLT_FN (BUILT_IN_ACOSH):
15093 CASE_FLT_FN (BUILT_IN_CABS):
15094 CASE_FLT_FN (BUILT_IN_COSH):
15095 CASE_FLT_FN (BUILT_IN_ERFC):
15096 CASE_FLT_FN (BUILT_IN_EXP):
15097 CASE_FLT_FN (BUILT_IN_EXP10):
15098 CASE_FLT_FN (BUILT_IN_EXP2):
15099 CASE_FLT_FN (BUILT_IN_FABS):
15100 CASE_FLT_FN (BUILT_IN_FDIM):
15101 CASE_FLT_FN (BUILT_IN_HYPOT):
15102 CASE_FLT_FN (BUILT_IN_POW10):
15103 CASE_INT_FN (BUILT_IN_FFS):
15104 CASE_INT_FN (BUILT_IN_PARITY):
15105 CASE_INT_FN (BUILT_IN_POPCOUNT):
15106 case BUILT_IN_BSWAP32:
15107 case BUILT_IN_BSWAP64:
15111 CASE_FLT_FN (BUILT_IN_SQRT):
15112 /* sqrt(-0.0) is -0.0. */
15113 if (!HONOR_SIGNED_ZEROS (TYPE_MODE (type)))
15115 return tree_expr_nonnegative_warnv_p (arg0,
15116 strict_overflow_p);
15118 CASE_FLT_FN (BUILT_IN_ASINH):
15119 CASE_FLT_FN (BUILT_IN_ATAN):
15120 CASE_FLT_FN (BUILT_IN_ATANH):
15121 CASE_FLT_FN (BUILT_IN_CBRT):
15122 CASE_FLT_FN (BUILT_IN_CEIL):
15123 CASE_FLT_FN (BUILT_IN_ERF):
15124 CASE_FLT_FN (BUILT_IN_EXPM1):
15125 CASE_FLT_FN (BUILT_IN_FLOOR):
15126 CASE_FLT_FN (BUILT_IN_FMOD):
15127 CASE_FLT_FN (BUILT_IN_FREXP):
15128 CASE_FLT_FN (BUILT_IN_LCEIL):
15129 CASE_FLT_FN (BUILT_IN_LDEXP):
15130 CASE_FLT_FN (BUILT_IN_LFLOOR):
15131 CASE_FLT_FN (BUILT_IN_LLCEIL):
15132 CASE_FLT_FN (BUILT_IN_LLFLOOR):
15133 CASE_FLT_FN (BUILT_IN_LLRINT):
15134 CASE_FLT_FN (BUILT_IN_LLROUND):
15135 CASE_FLT_FN (BUILT_IN_LRINT):
15136 CASE_FLT_FN (BUILT_IN_LROUND):
15137 CASE_FLT_FN (BUILT_IN_MODF):
15138 CASE_FLT_FN (BUILT_IN_NEARBYINT):
15139 CASE_FLT_FN (BUILT_IN_RINT):
15140 CASE_FLT_FN (BUILT_IN_ROUND):
15141 CASE_FLT_FN (BUILT_IN_SCALB):
15142 CASE_FLT_FN (BUILT_IN_SCALBLN):
15143 CASE_FLT_FN (BUILT_IN_SCALBN):
15144 CASE_FLT_FN (BUILT_IN_SIGNBIT):
15145 CASE_FLT_FN (BUILT_IN_SIGNIFICAND):
15146 CASE_FLT_FN (BUILT_IN_SINH):
15147 CASE_FLT_FN (BUILT_IN_TANH):
15148 CASE_FLT_FN (BUILT_IN_TRUNC):
15149 /* True if the 1st argument is nonnegative. */
15150 return tree_expr_nonnegative_warnv_p (arg0,
15151 strict_overflow_p);
15153 CASE_FLT_FN (BUILT_IN_FMAX):
15154 /* True if the 1st OR 2nd arguments are nonnegative. */
15155 return (tree_expr_nonnegative_warnv_p (arg0,
15157 || (tree_expr_nonnegative_warnv_p (arg1,
15158 strict_overflow_p)));
15160 CASE_FLT_FN (BUILT_IN_FMIN):
15161 /* True if the 1st AND 2nd arguments are nonnegative. */
15162 return (tree_expr_nonnegative_warnv_p (arg0,
15164 && (tree_expr_nonnegative_warnv_p (arg1,
15165 strict_overflow_p)));
15167 CASE_FLT_FN (BUILT_IN_COPYSIGN):
15168 /* True if the 2nd argument is nonnegative. */
15169 return tree_expr_nonnegative_warnv_p (arg1,
15170 strict_overflow_p);
15172 CASE_FLT_FN (BUILT_IN_POWI):
15173 /* True if the 1st argument is nonnegative or the second
15174 argument is an even integer. */
15175 if (TREE_CODE (arg1) == INTEGER_CST
15176 && (TREE_INT_CST_LOW (arg1) & 1) == 0)
15178 return tree_expr_nonnegative_warnv_p (arg0,
15179 strict_overflow_p);
15181 CASE_FLT_FN (BUILT_IN_POW):
15182 /* True if the 1st argument is nonnegative or the second
15183 argument is an even integer valued real. */
15184 if (TREE_CODE (arg1) == REAL_CST)
15189 c = TREE_REAL_CST (arg1);
15190 n = real_to_integer (&c);
15193 REAL_VALUE_TYPE cint;
15194 real_from_integer (&cint, VOIDmode, n,
15195 n < 0 ? -1 : 0, 0);
15196 if (real_identical (&c, &cint))
15200 return tree_expr_nonnegative_warnv_p (arg0,
15201 strict_overflow_p);
15206 return tree_simple_nonnegative_warnv_p (CALL_EXPR,
15210 /* Return true if T is known to be non-negative. If the return
15211 value is based on the assumption that signed overflow is undefined,
15212 set *STRICT_OVERFLOW_P to true; otherwise, don't change
15213 *STRICT_OVERFLOW_P. */
15216 tree_invalid_nonnegative_warnv_p (tree t, bool *strict_overflow_p)
15218 enum tree_code code = TREE_CODE (t);
15219 if (TYPE_UNSIGNED (TREE_TYPE (t)))
15226 tree temp = TARGET_EXPR_SLOT (t);
15227 t = TARGET_EXPR_INITIAL (t);
15229 /* If the initializer is non-void, then it's a normal expression
15230 that will be assigned to the slot. */
15231 if (!VOID_TYPE_P (t))
15232 return tree_expr_nonnegative_warnv_p (t, strict_overflow_p);
15234 /* Otherwise, the initializer sets the slot in some way. One common
15235 way is an assignment statement at the end of the initializer. */
15238 if (TREE_CODE (t) == BIND_EXPR)
15239 t = expr_last (BIND_EXPR_BODY (t));
15240 else if (TREE_CODE (t) == TRY_FINALLY_EXPR
15241 || TREE_CODE (t) == TRY_CATCH_EXPR)
15242 t = expr_last (TREE_OPERAND (t, 0));
15243 else if (TREE_CODE (t) == STATEMENT_LIST)
15248 if (TREE_CODE (t) == MODIFY_EXPR
15249 && TREE_OPERAND (t, 0) == temp)
15250 return tree_expr_nonnegative_warnv_p (TREE_OPERAND (t, 1),
15251 strict_overflow_p);
15258 tree arg0 = call_expr_nargs (t) > 0 ? CALL_EXPR_ARG (t, 0) : NULL_TREE;
15259 tree arg1 = call_expr_nargs (t) > 1 ? CALL_EXPR_ARG (t, 1) : NULL_TREE;
15261 return tree_call_nonnegative_warnv_p (TREE_TYPE (t),
15262 get_callee_fndecl (t),
15265 strict_overflow_p);
15267 case COMPOUND_EXPR:
15269 return tree_expr_nonnegative_warnv_p (TREE_OPERAND (t, 1),
15270 strict_overflow_p);
15272 return tree_expr_nonnegative_warnv_p (expr_last (TREE_OPERAND (t, 1)),
15273 strict_overflow_p);
15275 return tree_expr_nonnegative_warnv_p (TREE_OPERAND (t, 0),
15276 strict_overflow_p);
15279 return tree_simple_nonnegative_warnv_p (TREE_CODE (t),
15283 /* We don't know sign of `t', so be conservative and return false. */
15287 /* Return true if T is known to be non-negative. If the return
15288 value is based on the assumption that signed overflow is undefined,
15289 set *STRICT_OVERFLOW_P to true; otherwise, don't change
15290 *STRICT_OVERFLOW_P. */
15293 tree_expr_nonnegative_warnv_p (tree t, bool *strict_overflow_p)
15295 enum tree_code code;
15296 if (t == error_mark_node)
15299 code = TREE_CODE (t);
15300 switch (TREE_CODE_CLASS (code))
15303 case tcc_comparison:
15304 return tree_binary_nonnegative_warnv_p (TREE_CODE (t),
15306 TREE_OPERAND (t, 0),
15307 TREE_OPERAND (t, 1),
15308 strict_overflow_p);
15311 return tree_unary_nonnegative_warnv_p (TREE_CODE (t),
15313 TREE_OPERAND (t, 0),
15314 strict_overflow_p);
15317 case tcc_declaration:
15318 case tcc_reference:
15319 return tree_single_nonnegative_warnv_p (t, strict_overflow_p);
15327 case TRUTH_AND_EXPR:
15328 case TRUTH_OR_EXPR:
15329 case TRUTH_XOR_EXPR:
15330 return tree_binary_nonnegative_warnv_p (TREE_CODE (t),
15332 TREE_OPERAND (t, 0),
15333 TREE_OPERAND (t, 1),
15334 strict_overflow_p);
15335 case TRUTH_NOT_EXPR:
15336 return tree_unary_nonnegative_warnv_p (TREE_CODE (t),
15338 TREE_OPERAND (t, 0),
15339 strict_overflow_p);
15346 case WITH_SIZE_EXPR:
15348 return tree_single_nonnegative_warnv_p (t, strict_overflow_p);
15351 return tree_invalid_nonnegative_warnv_p (t, strict_overflow_p);
15355 /* Return true if `t' is known to be non-negative. Handle warnings
15356 about undefined signed overflow. */
15359 tree_expr_nonnegative_p (tree t)
15361 bool ret, strict_overflow_p;
15363 strict_overflow_p = false;
15364 ret = tree_expr_nonnegative_warnv_p (t, &strict_overflow_p);
15365 if (strict_overflow_p)
15366 fold_overflow_warning (("assuming signed overflow does not occur when "
15367 "determining that expression is always "
15369 WARN_STRICT_OVERFLOW_MISC);
15374 /* Return true when (CODE OP0) is an address and is known to be nonzero.
15375 For floating point we further ensure that T is not denormal.
15376 Similar logic is present in nonzero_address in rtlanal.h.
15378 If the return value is based on the assumption that signed overflow
15379 is undefined, set *STRICT_OVERFLOW_P to true; otherwise, don't
15380 change *STRICT_OVERFLOW_P. */
15383 tree_unary_nonzero_warnv_p (enum tree_code code, tree type, tree op0,
15384 bool *strict_overflow_p)
15389 return tree_expr_nonzero_warnv_p (op0,
15390 strict_overflow_p);
15394 tree inner_type = TREE_TYPE (op0);
15395 tree outer_type = type;
15397 return (TYPE_PRECISION (outer_type) >= TYPE_PRECISION (inner_type)
15398 && tree_expr_nonzero_warnv_p (op0,
15399 strict_overflow_p));
15403 case NON_LVALUE_EXPR:
15404 return tree_expr_nonzero_warnv_p (op0,
15405 strict_overflow_p);
15414 /* Return true when (CODE OP0 OP1) is an address and is known to be nonzero.
15415 For floating point we further ensure that T is not denormal.
15416 Similar logic is present in nonzero_address in rtlanal.h.
15418 If the return value is based on the assumption that signed overflow
15419 is undefined, set *STRICT_OVERFLOW_P to true; otherwise, don't
15420 change *STRICT_OVERFLOW_P. */
15423 tree_binary_nonzero_warnv_p (enum tree_code code,
15426 tree op1, bool *strict_overflow_p)
15428 bool sub_strict_overflow_p;
15431 case POINTER_PLUS_EXPR:
15433 if (TYPE_OVERFLOW_UNDEFINED (type))
15435 /* With the presence of negative values it is hard
15436 to say something. */
15437 sub_strict_overflow_p = false;
15438 if (!tree_expr_nonnegative_warnv_p (op0,
15439 &sub_strict_overflow_p)
15440 || !tree_expr_nonnegative_warnv_p (op1,
15441 &sub_strict_overflow_p))
15443 /* One of operands must be positive and the other non-negative. */
15444 /* We don't set *STRICT_OVERFLOW_P here: even if this value
15445 overflows, on a twos-complement machine the sum of two
15446 nonnegative numbers can never be zero. */
15447 return (tree_expr_nonzero_warnv_p (op0,
15449 || tree_expr_nonzero_warnv_p (op1,
15450 strict_overflow_p));
15455 if (TYPE_OVERFLOW_UNDEFINED (type))
15457 if (tree_expr_nonzero_warnv_p (op0,
15459 && tree_expr_nonzero_warnv_p (op1,
15460 strict_overflow_p))
15462 *strict_overflow_p = true;
15469 sub_strict_overflow_p = false;
15470 if (tree_expr_nonzero_warnv_p (op0,
15471 &sub_strict_overflow_p)
15472 && tree_expr_nonzero_warnv_p (op1,
15473 &sub_strict_overflow_p))
15475 if (sub_strict_overflow_p)
15476 *strict_overflow_p = true;
15481 sub_strict_overflow_p = false;
15482 if (tree_expr_nonzero_warnv_p (op0,
15483 &sub_strict_overflow_p))
15485 if (sub_strict_overflow_p)
15486 *strict_overflow_p = true;
15488 /* When both operands are nonzero, then MAX must be too. */
15489 if (tree_expr_nonzero_warnv_p (op1,
15490 strict_overflow_p))
15493 /* MAX where operand 0 is positive is positive. */
15494 return tree_expr_nonnegative_warnv_p (op0,
15495 strict_overflow_p);
15497 /* MAX where operand 1 is positive is positive. */
15498 else if (tree_expr_nonzero_warnv_p (op1,
15499 &sub_strict_overflow_p)
15500 && tree_expr_nonnegative_warnv_p (op1,
15501 &sub_strict_overflow_p))
15503 if (sub_strict_overflow_p)
15504 *strict_overflow_p = true;
15510 return (tree_expr_nonzero_warnv_p (op1,
15512 || tree_expr_nonzero_warnv_p (op0,
15513 strict_overflow_p));
15522 /* Return true when T is an address and is known to be nonzero.
15523 For floating point we further ensure that T is not denormal.
15524 Similar logic is present in nonzero_address in rtlanal.h.
15526 If the return value is based on the assumption that signed overflow
15527 is undefined, set *STRICT_OVERFLOW_P to true; otherwise, don't
15528 change *STRICT_OVERFLOW_P. */
15531 tree_single_nonzero_warnv_p (tree t, bool *strict_overflow_p)
15533 bool sub_strict_overflow_p;
15534 switch (TREE_CODE (t))
15537 return !integer_zerop (t);
15541 tree base = get_base_address (TREE_OPERAND (t, 0));
15546 /* Weak declarations may link to NULL. Other things may also be NULL
15547 so protect with -fdelete-null-pointer-checks; but not variables
15548 allocated on the stack. */
15550 && (flag_delete_null_pointer_checks
15551 || (TREE_CODE (base) == VAR_DECL && !TREE_STATIC (base))))
15552 return !VAR_OR_FUNCTION_DECL_P (base) || !DECL_WEAK (base);
15554 /* Constants are never weak. */
15555 if (CONSTANT_CLASS_P (base))
15562 sub_strict_overflow_p = false;
15563 if (tree_expr_nonzero_warnv_p (TREE_OPERAND (t, 1),
15564 &sub_strict_overflow_p)
15565 && tree_expr_nonzero_warnv_p (TREE_OPERAND (t, 2),
15566 &sub_strict_overflow_p))
15568 if (sub_strict_overflow_p)
15569 *strict_overflow_p = true;
15580 /* Return true when T is an address and is known to be nonzero.
15581 For floating point we further ensure that T is not denormal.
15582 Similar logic is present in nonzero_address in rtlanal.h.
15584 If the return value is based on the assumption that signed overflow
15585 is undefined, set *STRICT_OVERFLOW_P to true; otherwise, don't
15586 change *STRICT_OVERFLOW_P. */
15589 tree_expr_nonzero_warnv_p (tree t, bool *strict_overflow_p)
15591 tree type = TREE_TYPE (t);
15592 enum tree_code code;
15594 /* Doing something useful for floating point would need more work. */
15595 if (!INTEGRAL_TYPE_P (type) && !POINTER_TYPE_P (type))
15598 code = TREE_CODE (t);
15599 switch (TREE_CODE_CLASS (code))
15602 return tree_unary_nonzero_warnv_p (code, type, TREE_OPERAND (t, 0),
15603 strict_overflow_p);
15605 case tcc_comparison:
15606 return tree_binary_nonzero_warnv_p (code, type,
15607 TREE_OPERAND (t, 0),
15608 TREE_OPERAND (t, 1),
15609 strict_overflow_p);
15611 case tcc_declaration:
15612 case tcc_reference:
15613 return tree_single_nonzero_warnv_p (t, strict_overflow_p);
15621 case TRUTH_NOT_EXPR:
15622 return tree_unary_nonzero_warnv_p (code, type, TREE_OPERAND (t, 0),
15623 strict_overflow_p);
15625 case TRUTH_AND_EXPR:
15626 case TRUTH_OR_EXPR:
15627 case TRUTH_XOR_EXPR:
15628 return tree_binary_nonzero_warnv_p (code, type,
15629 TREE_OPERAND (t, 0),
15630 TREE_OPERAND (t, 1),
15631 strict_overflow_p);
15638 case WITH_SIZE_EXPR:
15640 return tree_single_nonzero_warnv_p (t, strict_overflow_p);
15642 case COMPOUND_EXPR:
15645 return tree_expr_nonzero_warnv_p (TREE_OPERAND (t, 1),
15646 strict_overflow_p);
15649 return tree_expr_nonzero_warnv_p (TREE_OPERAND (t, 0),
15650 strict_overflow_p);
15653 return alloca_call_p (t);
15661 /* Return true when T is an address and is known to be nonzero.
15662 Handle warnings about undefined signed overflow. */
15665 tree_expr_nonzero_p (tree t)
15667 bool ret, strict_overflow_p;
15669 strict_overflow_p = false;
15670 ret = tree_expr_nonzero_warnv_p (t, &strict_overflow_p);
15671 if (strict_overflow_p)
15672 fold_overflow_warning (("assuming signed overflow does not occur when "
15673 "determining that expression is always "
15675 WARN_STRICT_OVERFLOW_MISC);
15679 /* Given the components of a binary expression CODE, TYPE, OP0 and OP1,
15680 attempt to fold the expression to a constant without modifying TYPE,
15683 If the expression could be simplified to a constant, then return
15684 the constant. If the expression would not be simplified to a
15685 constant, then return NULL_TREE. */
15688 fold_binary_to_constant (enum tree_code code, tree type, tree op0, tree op1)
15690 tree tem = fold_binary (code, type, op0, op1);
15691 return (tem && TREE_CONSTANT (tem)) ? tem : NULL_TREE;
15694 /* Given the components of a unary expression CODE, TYPE and OP0,
15695 attempt to fold the expression to a constant without modifying
15698 If the expression could be simplified to a constant, then return
15699 the constant. If the expression would not be simplified to a
15700 constant, then return NULL_TREE. */
15703 fold_unary_to_constant (enum tree_code code, tree type, tree op0)
15705 tree tem = fold_unary (code, type, op0);
15706 return (tem && TREE_CONSTANT (tem)) ? tem : NULL_TREE;
15709 /* If EXP represents referencing an element in a constant string
15710 (either via pointer arithmetic or array indexing), return the
15711 tree representing the value accessed, otherwise return NULL. */
15714 fold_read_from_constant_string (tree exp)
15716 if ((TREE_CODE (exp) == INDIRECT_REF
15717 || TREE_CODE (exp) == ARRAY_REF)
15718 && TREE_CODE (TREE_TYPE (exp)) == INTEGER_TYPE)
15720 tree exp1 = TREE_OPERAND (exp, 0);
15723 location_t loc = EXPR_LOCATION (exp);
15725 if (TREE_CODE (exp) == INDIRECT_REF)
15726 string = string_constant (exp1, &index);
15729 tree low_bound = array_ref_low_bound (exp);
15730 index = fold_convert_loc (loc, sizetype, TREE_OPERAND (exp, 1));
15732 /* Optimize the special-case of a zero lower bound.
15734 We convert the low_bound to sizetype to avoid some problems
15735 with constant folding. (E.g. suppose the lower bound is 1,
15736 and its mode is QI. Without the conversion,l (ARRAY
15737 +(INDEX-(unsigned char)1)) becomes ((ARRAY+(-(unsigned char)1))
15738 +INDEX), which becomes (ARRAY+255+INDEX). Oops!) */
15739 if (! integer_zerop (low_bound))
15740 index = size_diffop_loc (loc, index,
15741 fold_convert_loc (loc, sizetype, low_bound));
15747 && TYPE_MODE (TREE_TYPE (exp)) == TYPE_MODE (TREE_TYPE (TREE_TYPE (string)))
15748 && TREE_CODE (string) == STRING_CST
15749 && TREE_CODE (index) == INTEGER_CST
15750 && compare_tree_int (index, TREE_STRING_LENGTH (string)) < 0
15751 && (GET_MODE_CLASS (TYPE_MODE (TREE_TYPE (TREE_TYPE (string))))
15753 && (GET_MODE_SIZE (TYPE_MODE (TREE_TYPE (TREE_TYPE (string)))) == 1))
15754 return build_int_cst_type (TREE_TYPE (exp),
15755 (TREE_STRING_POINTER (string)
15756 [TREE_INT_CST_LOW (index)]));
15761 /* Return the tree for neg (ARG0) when ARG0 is known to be either
15762 an integer constant, real, or fixed-point constant.
15764 TYPE is the type of the result. */
15767 fold_negate_const (tree arg0, tree type)
15769 tree t = NULL_TREE;
15771 switch (TREE_CODE (arg0))
15775 unsigned HOST_WIDE_INT low;
15776 HOST_WIDE_INT high;
15777 int overflow = neg_double (TREE_INT_CST_LOW (arg0),
15778 TREE_INT_CST_HIGH (arg0),
15780 t = force_fit_type_double (type, low, high, 1,
15781 (overflow | TREE_OVERFLOW (arg0))
15782 && !TYPE_UNSIGNED (type));
15787 t = build_real (type, REAL_VALUE_NEGATE (TREE_REAL_CST (arg0)));
15792 FIXED_VALUE_TYPE f;
15793 bool overflow_p = fixed_arithmetic (&f, NEGATE_EXPR,
15794 &(TREE_FIXED_CST (arg0)), NULL,
15795 TYPE_SATURATING (type));
15796 t = build_fixed (type, f);
15797 /* Propagate overflow flags. */
15798 if (overflow_p | TREE_OVERFLOW (arg0))
15799 TREE_OVERFLOW (t) = 1;
15804 gcc_unreachable ();
15810 /* Return the tree for abs (ARG0) when ARG0 is known to be either
15811 an integer constant or real constant.
15813 TYPE is the type of the result. */
15816 fold_abs_const (tree arg0, tree type)
15818 tree t = NULL_TREE;
15820 switch (TREE_CODE (arg0))
15823 /* If the value is unsigned, then the absolute value is
15824 the same as the ordinary value. */
15825 if (TYPE_UNSIGNED (type))
15827 /* Similarly, if the value is non-negative. */
15828 else if (INT_CST_LT (integer_minus_one_node, arg0))
15830 /* If the value is negative, then the absolute value is
15834 unsigned HOST_WIDE_INT low;
15835 HOST_WIDE_INT high;
15836 int overflow = neg_double (TREE_INT_CST_LOW (arg0),
15837 TREE_INT_CST_HIGH (arg0),
15839 t = force_fit_type_double (type, low, high, -1,
15840 overflow | TREE_OVERFLOW (arg0));
15845 if (REAL_VALUE_NEGATIVE (TREE_REAL_CST (arg0)))
15846 t = build_real (type, REAL_VALUE_NEGATE (TREE_REAL_CST (arg0)));
15852 gcc_unreachable ();
15858 /* Return the tree for not (ARG0) when ARG0 is known to be an integer
15859 constant. TYPE is the type of the result. */
15862 fold_not_const (tree arg0, tree type)
15864 tree t = NULL_TREE;
15866 gcc_assert (TREE_CODE (arg0) == INTEGER_CST);
15868 t = force_fit_type_double (type, ~TREE_INT_CST_LOW (arg0),
15869 ~TREE_INT_CST_HIGH (arg0), 0,
15870 TREE_OVERFLOW (arg0));
15875 /* Given CODE, a relational operator, the target type, TYPE and two
15876 constant operands OP0 and OP1, return the result of the
15877 relational operation. If the result is not a compile time
15878 constant, then return NULL_TREE. */
15881 fold_relational_const (enum tree_code code, tree type, tree op0, tree op1)
15883 int result, invert;
15885 /* From here on, the only cases we handle are when the result is
15886 known to be a constant. */
15888 if (TREE_CODE (op0) == REAL_CST && TREE_CODE (op1) == REAL_CST)
15890 const REAL_VALUE_TYPE *c0 = TREE_REAL_CST_PTR (op0);
15891 const REAL_VALUE_TYPE *c1 = TREE_REAL_CST_PTR (op1);
15893 /* Handle the cases where either operand is a NaN. */
15894 if (real_isnan (c0) || real_isnan (c1))
15904 case UNORDERED_EXPR:
15918 if (flag_trapping_math)
15924 gcc_unreachable ();
15927 return constant_boolean_node (result, type);
15930 return constant_boolean_node (real_compare (code, c0, c1), type);
15933 if (TREE_CODE (op0) == FIXED_CST && TREE_CODE (op1) == FIXED_CST)
15935 const FIXED_VALUE_TYPE *c0 = TREE_FIXED_CST_PTR (op0);
15936 const FIXED_VALUE_TYPE *c1 = TREE_FIXED_CST_PTR (op1);
15937 return constant_boolean_node (fixed_compare (code, c0, c1), type);
15940 /* Handle equality/inequality of complex constants. */
15941 if (TREE_CODE (op0) == COMPLEX_CST && TREE_CODE (op1) == COMPLEX_CST)
15943 tree rcond = fold_relational_const (code, type,
15944 TREE_REALPART (op0),
15945 TREE_REALPART (op1));
15946 tree icond = fold_relational_const (code, type,
15947 TREE_IMAGPART (op0),
15948 TREE_IMAGPART (op1));
15949 if (code == EQ_EXPR)
15950 return fold_build2 (TRUTH_ANDIF_EXPR, type, rcond, icond);
15951 else if (code == NE_EXPR)
15952 return fold_build2 (TRUTH_ORIF_EXPR, type, rcond, icond);
15957 /* From here on we only handle LT, LE, GT, GE, EQ and NE.
15959 To compute GT, swap the arguments and do LT.
15960 To compute GE, do LT and invert the result.
15961 To compute LE, swap the arguments, do LT and invert the result.
15962 To compute NE, do EQ and invert the result.
15964 Therefore, the code below must handle only EQ and LT. */
15966 if (code == LE_EXPR || code == GT_EXPR)
15971 code = swap_tree_comparison (code);
15974 /* Note that it is safe to invert for real values here because we
15975 have already handled the one case that it matters. */
15978 if (code == NE_EXPR || code == GE_EXPR)
15981 code = invert_tree_comparison (code, false);
15984 /* Compute a result for LT or EQ if args permit;
15985 Otherwise return T. */
15986 if (TREE_CODE (op0) == INTEGER_CST && TREE_CODE (op1) == INTEGER_CST)
15988 if (code == EQ_EXPR)
15989 result = tree_int_cst_equal (op0, op1);
15990 else if (TYPE_UNSIGNED (TREE_TYPE (op0)))
15991 result = INT_CST_LT_UNSIGNED (op0, op1);
15993 result = INT_CST_LT (op0, op1);
16000 return constant_boolean_node (result, type);
16003 /* If necessary, return a CLEANUP_POINT_EXPR for EXPR with the
16004 indicated TYPE. If no CLEANUP_POINT_EXPR is necessary, return EXPR
16008 fold_build_cleanup_point_expr (tree type, tree expr)
16010 /* If the expression does not have side effects then we don't have to wrap
16011 it with a cleanup point expression. */
16012 if (!TREE_SIDE_EFFECTS (expr))
16015 /* If the expression is a return, check to see if the expression inside the
16016 return has no side effects or the right hand side of the modify expression
16017 inside the return. If either don't have side effects set we don't need to
16018 wrap the expression in a cleanup point expression. Note we don't check the
16019 left hand side of the modify because it should always be a return decl. */
16020 if (TREE_CODE (expr) == RETURN_EXPR)
16022 tree op = TREE_OPERAND (expr, 0);
16023 if (!op || !TREE_SIDE_EFFECTS (op))
16025 op = TREE_OPERAND (op, 1);
16026 if (!TREE_SIDE_EFFECTS (op))
16030 return build1 (CLEANUP_POINT_EXPR, type, expr);
16033 /* Given a pointer value OP0 and a type TYPE, return a simplified version
16034 of an indirection through OP0, or NULL_TREE if no simplification is
16038 fold_indirect_ref_1 (location_t loc, tree type, tree op0)
16044 subtype = TREE_TYPE (sub);
16045 if (!POINTER_TYPE_P (subtype))
16048 if (TREE_CODE (sub) == ADDR_EXPR)
16050 tree op = TREE_OPERAND (sub, 0);
16051 tree optype = TREE_TYPE (op);
16052 /* *&CONST_DECL -> to the value of the const decl. */
16053 if (TREE_CODE (op) == CONST_DECL)
16054 return DECL_INITIAL (op);
16055 /* *&p => p; make sure to handle *&"str"[cst] here. */
16056 if (type == optype)
16058 tree fop = fold_read_from_constant_string (op);
16064 /* *(foo *)&fooarray => fooarray[0] */
16065 else if (TREE_CODE (optype) == ARRAY_TYPE
16066 && type == TREE_TYPE (optype))
16068 tree type_domain = TYPE_DOMAIN (optype);
16069 tree min_val = size_zero_node;
16070 if (type_domain && TYPE_MIN_VALUE (type_domain))
16071 min_val = TYPE_MIN_VALUE (type_domain);
16072 op0 = build4 (ARRAY_REF, type, op, min_val, NULL_TREE, NULL_TREE);
16073 SET_EXPR_LOCATION (op0, loc);
16076 /* *(foo *)&complexfoo => __real__ complexfoo */
16077 else if (TREE_CODE (optype) == COMPLEX_TYPE
16078 && type == TREE_TYPE (optype))
16079 return fold_build1_loc (loc, REALPART_EXPR, type, op);
16080 /* *(foo *)&vectorfoo => BIT_FIELD_REF<vectorfoo,...> */
16081 else if (TREE_CODE (optype) == VECTOR_TYPE
16082 && type == TREE_TYPE (optype))
16084 tree part_width = TYPE_SIZE (type);
16085 tree index = bitsize_int (0);
16086 return fold_build3_loc (loc, BIT_FIELD_REF, type, op, part_width, index);
16090 /* ((foo*)&vectorfoo)[1] => BIT_FIELD_REF<vectorfoo,...> */
16091 if (TREE_CODE (sub) == POINTER_PLUS_EXPR
16092 && TREE_CODE (TREE_OPERAND (sub, 1)) == INTEGER_CST)
16094 tree op00 = TREE_OPERAND (sub, 0);
16095 tree op01 = TREE_OPERAND (sub, 1);
16099 op00type = TREE_TYPE (op00);
16100 if (TREE_CODE (op00) == ADDR_EXPR
16101 && TREE_CODE (TREE_TYPE (op00type)) == VECTOR_TYPE
16102 && type == TREE_TYPE (TREE_TYPE (op00type)))
16104 HOST_WIDE_INT offset = tree_low_cst (op01, 0);
16105 tree part_width = TYPE_SIZE (type);
16106 unsigned HOST_WIDE_INT part_widthi = tree_low_cst (part_width, 0)/BITS_PER_UNIT;
16107 unsigned HOST_WIDE_INT indexi = offset * BITS_PER_UNIT;
16108 tree index = bitsize_int (indexi);
16110 if (offset/part_widthi <= TYPE_VECTOR_SUBPARTS (TREE_TYPE (op00type)))
16111 return fold_build3_loc (loc,
16112 BIT_FIELD_REF, type, TREE_OPERAND (op00, 0),
16113 part_width, index);
16119 /* ((foo*)&complexfoo)[1] => __imag__ complexfoo */
16120 if (TREE_CODE (sub) == POINTER_PLUS_EXPR
16121 && TREE_CODE (TREE_OPERAND (sub, 1)) == INTEGER_CST)
16123 tree op00 = TREE_OPERAND (sub, 0);
16124 tree op01 = TREE_OPERAND (sub, 1);
16128 op00type = TREE_TYPE (op00);
16129 if (TREE_CODE (op00) == ADDR_EXPR
16130 && TREE_CODE (TREE_TYPE (op00type)) == COMPLEX_TYPE
16131 && type == TREE_TYPE (TREE_TYPE (op00type)))
16133 tree size = TYPE_SIZE_UNIT (type);
16134 if (tree_int_cst_equal (size, op01))
16135 return fold_build1_loc (loc, IMAGPART_EXPR, type,
16136 TREE_OPERAND (op00, 0));
16140 /* *(foo *)fooarrptr => (*fooarrptr)[0] */
16141 if (TREE_CODE (TREE_TYPE (subtype)) == ARRAY_TYPE
16142 && type == TREE_TYPE (TREE_TYPE (subtype)))
16145 tree min_val = size_zero_node;
16146 sub = build_fold_indirect_ref_loc (loc, sub);
16147 type_domain = TYPE_DOMAIN (TREE_TYPE (sub));
16148 if (type_domain && TYPE_MIN_VALUE (type_domain))
16149 min_val = TYPE_MIN_VALUE (type_domain);
16150 op0 = build4 (ARRAY_REF, type, sub, min_val, NULL_TREE, NULL_TREE);
16151 SET_EXPR_LOCATION (op0, loc);
16158 /* Builds an expression for an indirection through T, simplifying some
16162 build_fold_indirect_ref_loc (location_t loc, tree t)
16164 tree type = TREE_TYPE (TREE_TYPE (t));
16165 tree sub = fold_indirect_ref_1 (loc, type, t);
16170 t = build1 (INDIRECT_REF, type, t);
16171 SET_EXPR_LOCATION (t, loc);
16175 /* Given an INDIRECT_REF T, return either T or a simplified version. */
16178 fold_indirect_ref_loc (location_t loc, tree t)
16180 tree sub = fold_indirect_ref_1 (loc, TREE_TYPE (t), TREE_OPERAND (t, 0));
16188 /* Strip non-trapping, non-side-effecting tree nodes from an expression
16189 whose result is ignored. The type of the returned tree need not be
16190 the same as the original expression. */
16193 fold_ignored_result (tree t)
16195 if (!TREE_SIDE_EFFECTS (t))
16196 return integer_zero_node;
16199 switch (TREE_CODE_CLASS (TREE_CODE (t)))
16202 t = TREE_OPERAND (t, 0);
16206 case tcc_comparison:
16207 if (!TREE_SIDE_EFFECTS (TREE_OPERAND (t, 1)))
16208 t = TREE_OPERAND (t, 0);
16209 else if (!TREE_SIDE_EFFECTS (TREE_OPERAND (t, 0)))
16210 t = TREE_OPERAND (t, 1);
16215 case tcc_expression:
16216 switch (TREE_CODE (t))
16218 case COMPOUND_EXPR:
16219 if (TREE_SIDE_EFFECTS (TREE_OPERAND (t, 1)))
16221 t = TREE_OPERAND (t, 0);
16225 if (TREE_SIDE_EFFECTS (TREE_OPERAND (t, 1))
16226 || TREE_SIDE_EFFECTS (TREE_OPERAND (t, 2)))
16228 t = TREE_OPERAND (t, 0);
16241 /* Return the value of VALUE, rounded up to a multiple of DIVISOR.
16242 This can only be applied to objects of a sizetype. */
16245 round_up_loc (location_t loc, tree value, int divisor)
16247 tree div = NULL_TREE;
16249 gcc_assert (divisor > 0);
16253 /* See if VALUE is already a multiple of DIVISOR. If so, we don't
16254 have to do anything. Only do this when we are not given a const,
16255 because in that case, this check is more expensive than just
16257 if (TREE_CODE (value) != INTEGER_CST)
16259 div = build_int_cst (TREE_TYPE (value), divisor);
16261 if (multiple_of_p (TREE_TYPE (value), value, div))
16265 /* If divisor is a power of two, simplify this to bit manipulation. */
16266 if (divisor == (divisor & -divisor))
16268 if (TREE_CODE (value) == INTEGER_CST)
16270 unsigned HOST_WIDE_INT low = TREE_INT_CST_LOW (value);
16271 unsigned HOST_WIDE_INT high;
16274 if ((low & (divisor - 1)) == 0)
16277 overflow_p = TREE_OVERFLOW (value);
16278 high = TREE_INT_CST_HIGH (value);
16279 low &= ~(divisor - 1);
16288 return force_fit_type_double (TREE_TYPE (value), low, high,
16295 t = build_int_cst (TREE_TYPE (value), divisor - 1);
16296 value = size_binop_loc (loc, PLUS_EXPR, value, t);
16297 t = build_int_cst (TREE_TYPE (value), -divisor);
16298 value = size_binop_loc (loc, BIT_AND_EXPR, value, t);
16304 div = build_int_cst (TREE_TYPE (value), divisor);
16305 value = size_binop_loc (loc, CEIL_DIV_EXPR, value, div);
16306 value = size_binop_loc (loc, MULT_EXPR, value, div);
16312 /* Likewise, but round down. */
16315 round_down_loc (location_t loc, tree value, int divisor)
16317 tree div = NULL_TREE;
16319 gcc_assert (divisor > 0);
16323 /* See if VALUE is already a multiple of DIVISOR. If so, we don't
16324 have to do anything. Only do this when we are not given a const,
16325 because in that case, this check is more expensive than just
16327 if (TREE_CODE (value) != INTEGER_CST)
16329 div = build_int_cst (TREE_TYPE (value), divisor);
16331 if (multiple_of_p (TREE_TYPE (value), value, div))
16335 /* If divisor is a power of two, simplify this to bit manipulation. */
16336 if (divisor == (divisor & -divisor))
16340 t = build_int_cst (TREE_TYPE (value), -divisor);
16341 value = size_binop_loc (loc, BIT_AND_EXPR, value, t);
16346 div = build_int_cst (TREE_TYPE (value), divisor);
16347 value = size_binop_loc (loc, FLOOR_DIV_EXPR, value, div);
16348 value = size_binop_loc (loc, MULT_EXPR, value, div);
16354 /* Returns the pointer to the base of the object addressed by EXP and
16355 extracts the information about the offset of the access, storing it
16356 to PBITPOS and POFFSET. */
16359 split_address_to_core_and_offset (tree exp,
16360 HOST_WIDE_INT *pbitpos, tree *poffset)
16363 enum machine_mode mode;
16364 int unsignedp, volatilep;
16365 HOST_WIDE_INT bitsize;
16366 location_t loc = EXPR_LOCATION (exp);
16368 if (TREE_CODE (exp) == ADDR_EXPR)
16370 core = get_inner_reference (TREE_OPERAND (exp, 0), &bitsize, pbitpos,
16371 poffset, &mode, &unsignedp, &volatilep,
16373 core = build_fold_addr_expr_loc (loc, core);
16379 *poffset = NULL_TREE;
16385 /* Returns true if addresses of E1 and E2 differ by a constant, false
16386 otherwise. If they do, E1 - E2 is stored in *DIFF. */
16389 ptr_difference_const (tree e1, tree e2, HOST_WIDE_INT *diff)
16392 HOST_WIDE_INT bitpos1, bitpos2;
16393 tree toffset1, toffset2, tdiff, type;
16395 core1 = split_address_to_core_and_offset (e1, &bitpos1, &toffset1);
16396 core2 = split_address_to_core_and_offset (e2, &bitpos2, &toffset2);
16398 if (bitpos1 % BITS_PER_UNIT != 0
16399 || bitpos2 % BITS_PER_UNIT != 0
16400 || !operand_equal_p (core1, core2, 0))
16403 if (toffset1 && toffset2)
16405 type = TREE_TYPE (toffset1);
16406 if (type != TREE_TYPE (toffset2))
16407 toffset2 = fold_convert (type, toffset2);
16409 tdiff = fold_build2 (MINUS_EXPR, type, toffset1, toffset2);
16410 if (!cst_and_fits_in_hwi (tdiff))
16413 *diff = int_cst_value (tdiff);
16415 else if (toffset1 || toffset2)
16417 /* If only one of the offsets is non-constant, the difference cannot
16424 *diff += (bitpos1 - bitpos2) / BITS_PER_UNIT;
16428 /* Simplify the floating point expression EXP when the sign of the
16429 result is not significant. Return NULL_TREE if no simplification
16433 fold_strip_sign_ops (tree exp)
16436 location_t loc = EXPR_LOCATION (exp);
16438 switch (TREE_CODE (exp))
16442 arg0 = fold_strip_sign_ops (TREE_OPERAND (exp, 0));
16443 return arg0 ? arg0 : TREE_OPERAND (exp, 0);
16447 if (HONOR_SIGN_DEPENDENT_ROUNDING (TYPE_MODE (TREE_TYPE (exp))))
16449 arg0 = fold_strip_sign_ops (TREE_OPERAND (exp, 0));
16450 arg1 = fold_strip_sign_ops (TREE_OPERAND (exp, 1));
16451 if (arg0 != NULL_TREE || arg1 != NULL_TREE)
16452 return fold_build2_loc (loc, TREE_CODE (exp), TREE_TYPE (exp),
16453 arg0 ? arg0 : TREE_OPERAND (exp, 0),
16454 arg1 ? arg1 : TREE_OPERAND (exp, 1));
16457 case COMPOUND_EXPR:
16458 arg0 = TREE_OPERAND (exp, 0);
16459 arg1 = fold_strip_sign_ops (TREE_OPERAND (exp, 1));
16461 return fold_build2_loc (loc, COMPOUND_EXPR, TREE_TYPE (exp), arg0, arg1);
16465 arg0 = fold_strip_sign_ops (TREE_OPERAND (exp, 1));
16466 arg1 = fold_strip_sign_ops (TREE_OPERAND (exp, 2));
16468 return fold_build3_loc (loc,
16469 COND_EXPR, TREE_TYPE (exp), TREE_OPERAND (exp, 0),
16470 arg0 ? arg0 : TREE_OPERAND (exp, 1),
16471 arg1 ? arg1 : TREE_OPERAND (exp, 2));
16476 const enum built_in_function fcode = builtin_mathfn_code (exp);
16479 CASE_FLT_FN (BUILT_IN_COPYSIGN):
16480 /* Strip copysign function call, return the 1st argument. */
16481 arg0 = CALL_EXPR_ARG (exp, 0);
16482 arg1 = CALL_EXPR_ARG (exp, 1);
16483 return omit_one_operand_loc (loc, TREE_TYPE (exp), arg0, arg1);
16486 /* Strip sign ops from the argument of "odd" math functions. */
16487 if (negate_mathfn_p (fcode))
16489 arg0 = fold_strip_sign_ops (CALL_EXPR_ARG (exp, 0));
16491 return build_call_expr_loc (loc, get_callee_fndecl (exp), 1, arg0);