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
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"
69 /* Nonzero if we are folding constants inside an initializer; zero
71 int folding_initializer = 0;
73 /* The following constants represent a bit based encoding of GCC's
74 comparison operators. This encoding simplifies transformations
75 on relational comparison operators, such as AND and OR. */
76 enum comparison_code {
95 static void encode (HOST_WIDE_INT *, unsigned HOST_WIDE_INT, HOST_WIDE_INT);
96 static void decode (HOST_WIDE_INT *, unsigned HOST_WIDE_INT *, HOST_WIDE_INT *);
97 static bool negate_mathfn_p (enum built_in_function);
98 static bool negate_expr_p (tree);
99 static tree negate_expr (tree);
100 static tree split_tree (tree, enum tree_code, tree *, tree *, tree *, int);
101 static tree associate_trees (tree, tree, enum tree_code, tree);
102 static tree const_binop (enum tree_code, tree, tree, int);
103 static enum comparison_code comparison_to_compcode (enum tree_code);
104 static enum tree_code compcode_to_comparison (enum comparison_code);
105 static tree combine_comparisons (enum tree_code, enum tree_code,
106 enum tree_code, tree, tree, tree);
107 static int truth_value_p (enum tree_code);
108 static int operand_equal_for_comparison_p (tree, tree, tree);
109 static int twoval_comparison_p (tree, tree *, tree *, int *);
110 static tree eval_subst (tree, tree, tree, tree, tree);
111 static tree pedantic_omit_one_operand (tree, tree, tree);
112 static tree distribute_bit_expr (enum tree_code, tree, tree, tree);
113 static tree decode_field_reference (tree, HOST_WIDE_INT *, HOST_WIDE_INT *,
114 enum machine_mode *, int *, int *,
116 static tree sign_bit_p (tree, const_tree);
117 static int simple_operand_p (const_tree);
118 static tree range_binop (enum tree_code, tree, tree, int, tree, int);
119 static tree range_predecessor (tree);
120 static tree range_successor (tree);
121 static tree make_range (tree, int *, tree *, tree *, bool *);
122 static tree build_range_check (tree, tree, int, tree, tree);
123 static int merge_ranges (int *, tree *, tree *, int, tree, tree, int, tree,
125 static tree fold_range_test (enum tree_code, tree, tree, tree);
126 static tree fold_cond_expr_with_comparison (tree, tree, tree, tree);
127 static tree unextend (tree, int, int, tree);
128 static tree fold_truthop (enum tree_code, tree, tree, tree);
129 static tree optimize_minmax_comparison (enum tree_code, tree, tree, tree);
130 static tree extract_muldiv (tree, tree, enum tree_code, tree, bool *);
131 static tree extract_muldiv_1 (tree, tree, enum tree_code, tree, bool *);
132 static tree fold_binary_op_with_conditional_arg (enum tree_code, tree,
135 static tree fold_mathfn_compare (enum built_in_function, enum tree_code,
137 static tree fold_inf_compare (enum tree_code, tree, tree, tree);
138 static tree fold_div_compare (enum tree_code, tree, tree, tree);
139 static bool reorder_operands_p (const_tree, const_tree);
140 static tree fold_negate_const (tree, tree);
141 static tree fold_not_const (tree, tree);
142 static tree fold_relational_const (enum tree_code, tree, tree, tree);
145 /* We know that A1 + B1 = SUM1, using 2's complement arithmetic and ignoring
146 overflow. Suppose A, B and SUM have the same respective signs as A1, B1,
147 and SUM1. Then this yields nonzero if overflow occurred during the
150 Overflow occurs if A and B have the same sign, but A and SUM differ in
151 sign. Use `^' to test whether signs differ, and `< 0' to isolate the
153 #define OVERFLOW_SUM_SIGN(a, b, sum) ((~((a) ^ (b)) & ((a) ^ (sum))) < 0)
155 /* To do constant folding on INTEGER_CST nodes requires two-word arithmetic.
156 We do that by representing the two-word integer in 4 words, with only
157 HOST_BITS_PER_WIDE_INT / 2 bits stored in each word, as a positive
158 number. The value of the word is LOWPART + HIGHPART * BASE. */
161 ((x) & (((unsigned HOST_WIDE_INT) 1 << (HOST_BITS_PER_WIDE_INT / 2)) - 1))
162 #define HIGHPART(x) \
163 ((unsigned HOST_WIDE_INT) (x) >> HOST_BITS_PER_WIDE_INT / 2)
164 #define BASE ((unsigned HOST_WIDE_INT) 1 << HOST_BITS_PER_WIDE_INT / 2)
166 /* Unpack a two-word integer into 4 words.
167 LOW and HI are the integer, as two `HOST_WIDE_INT' pieces.
168 WORDS points to the array of HOST_WIDE_INTs. */
171 encode (HOST_WIDE_INT *words, unsigned HOST_WIDE_INT low, HOST_WIDE_INT hi)
173 words[0] = LOWPART (low);
174 words[1] = HIGHPART (low);
175 words[2] = LOWPART (hi);
176 words[3] = HIGHPART (hi);
179 /* Pack an array of 4 words into a two-word integer.
180 WORDS points to the array of words.
181 The integer is stored into *LOW and *HI as two `HOST_WIDE_INT' pieces. */
184 decode (HOST_WIDE_INT *words, unsigned HOST_WIDE_INT *low,
187 *low = words[0] + words[1] * BASE;
188 *hi = words[2] + words[3] * BASE;
191 /* Force the double-word integer L1, H1 to be within the range of the
192 integer type TYPE. Stores the properly truncated and sign-extended
193 double-word integer in *LV, *HV. Returns true if the operation
194 overflows, that is, argument and result are different. */
197 fit_double_type (unsigned HOST_WIDE_INT l1, HOST_WIDE_INT h1,
198 unsigned HOST_WIDE_INT *lv, HOST_WIDE_INT *hv, const_tree type)
200 unsigned HOST_WIDE_INT low0 = l1;
201 HOST_WIDE_INT high0 = h1;
203 int sign_extended_type;
205 if (POINTER_TYPE_P (type)
206 || TREE_CODE (type) == OFFSET_TYPE)
209 prec = TYPE_PRECISION (type);
211 /* Size types *are* sign extended. */
212 sign_extended_type = (!TYPE_UNSIGNED (type)
213 || (TREE_CODE (type) == INTEGER_TYPE
214 && TYPE_IS_SIZETYPE (type)));
216 /* First clear all bits that are beyond the type's precision. */
217 if (prec >= 2 * HOST_BITS_PER_WIDE_INT)
219 else if (prec > HOST_BITS_PER_WIDE_INT)
220 h1 &= ~((HOST_WIDE_INT) (-1) << (prec - HOST_BITS_PER_WIDE_INT));
224 if (prec < HOST_BITS_PER_WIDE_INT)
225 l1 &= ~((HOST_WIDE_INT) (-1) << prec);
228 /* Then do sign extension if necessary. */
229 if (!sign_extended_type)
230 /* No sign extension */;
231 else if (prec >= 2 * HOST_BITS_PER_WIDE_INT)
232 /* Correct width already. */;
233 else if (prec > HOST_BITS_PER_WIDE_INT)
235 /* Sign extend top half? */
236 if (h1 & ((unsigned HOST_WIDE_INT)1
237 << (prec - HOST_BITS_PER_WIDE_INT - 1)))
238 h1 |= (HOST_WIDE_INT) (-1) << (prec - HOST_BITS_PER_WIDE_INT);
240 else if (prec == HOST_BITS_PER_WIDE_INT)
242 if ((HOST_WIDE_INT)l1 < 0)
247 /* Sign extend bottom half? */
248 if (l1 & ((unsigned HOST_WIDE_INT)1 << (prec - 1)))
251 l1 |= (HOST_WIDE_INT)(-1) << prec;
258 /* If the value didn't fit, signal overflow. */
259 return l1 != low0 || h1 != high0;
262 /* We force the double-int HIGH:LOW to the range of the type TYPE by
263 sign or zero extending it.
264 OVERFLOWABLE indicates if we are interested
265 in overflow of the value, when >0 we are only interested in signed
266 overflow, for <0 we are interested in any overflow. OVERFLOWED
267 indicates whether overflow has already occurred. CONST_OVERFLOWED
268 indicates whether constant overflow has already occurred. We force
269 T's value to be within range of T's type (by setting to 0 or 1 all
270 the bits outside the type's range). We set TREE_OVERFLOWED if,
271 OVERFLOWED is nonzero,
272 or OVERFLOWABLE is >0 and signed overflow occurs
273 or OVERFLOWABLE is <0 and any overflow occurs
274 We return a new tree node for the extended double-int. The node
275 is shared if no overflow flags are set. */
278 force_fit_type_double (tree type, unsigned HOST_WIDE_INT low,
279 HOST_WIDE_INT high, int overflowable,
282 int sign_extended_type;
285 /* Size types *are* sign extended. */
286 sign_extended_type = (!TYPE_UNSIGNED (type)
287 || (TREE_CODE (type) == INTEGER_TYPE
288 && TYPE_IS_SIZETYPE (type)));
290 overflow = fit_double_type (low, high, &low, &high, type);
292 /* If we need to set overflow flags, return a new unshared node. */
293 if (overflowed || overflow)
297 || (overflowable > 0 && sign_extended_type))
299 tree t = make_node (INTEGER_CST);
300 TREE_INT_CST_LOW (t) = low;
301 TREE_INT_CST_HIGH (t) = high;
302 TREE_TYPE (t) = type;
303 TREE_OVERFLOW (t) = 1;
308 /* Else build a shared node. */
309 return build_int_cst_wide (type, low, high);
312 /* Add two doubleword integers with doubleword result.
313 Return nonzero if the operation overflows according to UNSIGNED_P.
314 Each argument is given as two `HOST_WIDE_INT' pieces.
315 One argument is L1 and H1; the other, L2 and H2.
316 The value is stored as two `HOST_WIDE_INT' pieces in *LV and *HV. */
319 add_double_with_sign (unsigned HOST_WIDE_INT l1, HOST_WIDE_INT h1,
320 unsigned HOST_WIDE_INT l2, HOST_WIDE_INT h2,
321 unsigned HOST_WIDE_INT *lv, HOST_WIDE_INT *hv,
324 unsigned HOST_WIDE_INT l;
328 h = h1 + h2 + (l < l1);
334 return (unsigned HOST_WIDE_INT) h < (unsigned HOST_WIDE_INT) h1;
336 return OVERFLOW_SUM_SIGN (h1, h2, h);
339 /* Negate a doubleword integer with doubleword result.
340 Return nonzero if the operation overflows, assuming it's signed.
341 The argument is given as two `HOST_WIDE_INT' pieces in L1 and H1.
342 The value is stored as two `HOST_WIDE_INT' pieces in *LV and *HV. */
345 neg_double (unsigned HOST_WIDE_INT l1, HOST_WIDE_INT h1,
346 unsigned HOST_WIDE_INT *lv, HOST_WIDE_INT *hv)
352 return (*hv & h1) < 0;
362 /* Multiply two doubleword integers with doubleword result.
363 Return nonzero if the operation overflows according to UNSIGNED_P.
364 Each argument is given as two `HOST_WIDE_INT' pieces.
365 One argument is L1 and H1; the other, L2 and H2.
366 The value is stored as two `HOST_WIDE_INT' pieces in *LV and *HV. */
369 mul_double_with_sign (unsigned HOST_WIDE_INT l1, HOST_WIDE_INT h1,
370 unsigned HOST_WIDE_INT l2, HOST_WIDE_INT h2,
371 unsigned HOST_WIDE_INT *lv, HOST_WIDE_INT *hv,
374 HOST_WIDE_INT arg1[4];
375 HOST_WIDE_INT arg2[4];
376 HOST_WIDE_INT prod[4 * 2];
377 unsigned HOST_WIDE_INT carry;
379 unsigned HOST_WIDE_INT toplow, neglow;
380 HOST_WIDE_INT tophigh, neghigh;
382 encode (arg1, l1, h1);
383 encode (arg2, l2, h2);
385 memset (prod, 0, sizeof prod);
387 for (i = 0; i < 4; i++)
390 for (j = 0; j < 4; j++)
393 /* This product is <= 0xFFFE0001, the sum <= 0xFFFF0000. */
394 carry += arg1[i] * arg2[j];
395 /* Since prod[p] < 0xFFFF, this sum <= 0xFFFFFFFF. */
397 prod[k] = LOWPART (carry);
398 carry = HIGHPART (carry);
403 decode (prod, lv, hv);
404 decode (prod + 4, &toplow, &tophigh);
406 /* Unsigned overflow is immediate. */
408 return (toplow | tophigh) != 0;
410 /* Check for signed overflow by calculating the signed representation of the
411 top half of the result; it should agree with the low half's sign bit. */
414 neg_double (l2, h2, &neglow, &neghigh);
415 add_double (neglow, neghigh, toplow, tophigh, &toplow, &tophigh);
419 neg_double (l1, h1, &neglow, &neghigh);
420 add_double (neglow, neghigh, toplow, tophigh, &toplow, &tophigh);
422 return (*hv < 0 ? ~(toplow & tophigh) : toplow | tophigh) != 0;
425 /* Shift the doubleword integer in L1, H1 left by COUNT places
426 keeping only PREC bits of result.
427 Shift right if COUNT is negative.
428 ARITH nonzero specifies arithmetic shifting; otherwise use logical shift.
429 Store the value as two `HOST_WIDE_INT' pieces in *LV and *HV. */
432 lshift_double (unsigned HOST_WIDE_INT l1, HOST_WIDE_INT h1,
433 HOST_WIDE_INT count, unsigned int prec,
434 unsigned HOST_WIDE_INT *lv, HOST_WIDE_INT *hv, int arith)
436 unsigned HOST_WIDE_INT signmask;
440 rshift_double (l1, h1, -count, prec, lv, hv, arith);
444 if (SHIFT_COUNT_TRUNCATED)
447 if (count >= 2 * HOST_BITS_PER_WIDE_INT)
449 /* Shifting by the host word size is undefined according to the
450 ANSI standard, so we must handle this as a special case. */
454 else if (count >= HOST_BITS_PER_WIDE_INT)
456 *hv = l1 << (count - HOST_BITS_PER_WIDE_INT);
461 *hv = (((unsigned HOST_WIDE_INT) h1 << count)
462 | (l1 >> (HOST_BITS_PER_WIDE_INT - count - 1) >> 1));
466 /* Sign extend all bits that are beyond the precision. */
468 signmask = -((prec > HOST_BITS_PER_WIDE_INT
469 ? ((unsigned HOST_WIDE_INT) *hv
470 >> (prec - HOST_BITS_PER_WIDE_INT - 1))
471 : (*lv >> (prec - 1))) & 1);
473 if (prec >= 2 * HOST_BITS_PER_WIDE_INT)
475 else if (prec >= HOST_BITS_PER_WIDE_INT)
477 *hv &= ~((HOST_WIDE_INT) (-1) << (prec - HOST_BITS_PER_WIDE_INT));
478 *hv |= signmask << (prec - HOST_BITS_PER_WIDE_INT);
483 *lv &= ~((unsigned HOST_WIDE_INT) (-1) << prec);
484 *lv |= signmask << prec;
488 /* Shift the doubleword integer in L1, H1 right by COUNT places
489 keeping only PREC bits of result. COUNT must be positive.
490 ARITH nonzero specifies arithmetic shifting; otherwise use logical shift.
491 Store the value as two `HOST_WIDE_INT' pieces in *LV and *HV. */
494 rshift_double (unsigned HOST_WIDE_INT l1, HOST_WIDE_INT h1,
495 HOST_WIDE_INT count, unsigned int prec,
496 unsigned HOST_WIDE_INT *lv, HOST_WIDE_INT *hv,
499 unsigned HOST_WIDE_INT signmask;
502 ? -((unsigned HOST_WIDE_INT) h1 >> (HOST_BITS_PER_WIDE_INT - 1))
505 if (SHIFT_COUNT_TRUNCATED)
508 if (count >= 2 * HOST_BITS_PER_WIDE_INT)
510 /* Shifting by the host word size is undefined according to the
511 ANSI standard, so we must handle this as a special case. */
515 else if (count >= HOST_BITS_PER_WIDE_INT)
518 *lv = (unsigned HOST_WIDE_INT) h1 >> (count - HOST_BITS_PER_WIDE_INT);
522 *hv = (unsigned HOST_WIDE_INT) h1 >> count;
524 | ((unsigned HOST_WIDE_INT) h1 << (HOST_BITS_PER_WIDE_INT - count - 1) << 1));
527 /* Zero / sign extend all bits that are beyond the precision. */
529 if (count >= (HOST_WIDE_INT)prec)
534 else if ((prec - count) >= 2 * HOST_BITS_PER_WIDE_INT)
536 else if ((prec - count) >= HOST_BITS_PER_WIDE_INT)
538 *hv &= ~((HOST_WIDE_INT) (-1) << (prec - count - HOST_BITS_PER_WIDE_INT));
539 *hv |= signmask << (prec - count - HOST_BITS_PER_WIDE_INT);
544 *lv &= ~((unsigned HOST_WIDE_INT) (-1) << (prec - count));
545 *lv |= signmask << (prec - count);
549 /* Rotate the doubleword integer in L1, H1 left by COUNT places
550 keeping only PREC bits of result.
551 Rotate right if COUNT is negative.
552 Store the value as two `HOST_WIDE_INT' pieces in *LV and *HV. */
555 lrotate_double (unsigned HOST_WIDE_INT l1, HOST_WIDE_INT h1,
556 HOST_WIDE_INT count, unsigned int prec,
557 unsigned HOST_WIDE_INT *lv, HOST_WIDE_INT *hv)
559 unsigned HOST_WIDE_INT s1l, s2l;
560 HOST_WIDE_INT s1h, s2h;
566 lshift_double (l1, h1, count, prec, &s1l, &s1h, 0);
567 rshift_double (l1, h1, prec - count, prec, &s2l, &s2h, 0);
572 /* Rotate the doubleword integer in L1, H1 left by COUNT places
573 keeping only PREC bits of result. COUNT must be positive.
574 Store the value as two `HOST_WIDE_INT' pieces in *LV and *HV. */
577 rrotate_double (unsigned HOST_WIDE_INT l1, HOST_WIDE_INT h1,
578 HOST_WIDE_INT count, unsigned int prec,
579 unsigned HOST_WIDE_INT *lv, HOST_WIDE_INT *hv)
581 unsigned HOST_WIDE_INT s1l, s2l;
582 HOST_WIDE_INT s1h, s2h;
588 rshift_double (l1, h1, count, prec, &s1l, &s1h, 0);
589 lshift_double (l1, h1, prec - count, prec, &s2l, &s2h, 0);
594 /* Divide doubleword integer LNUM, HNUM by doubleword integer LDEN, HDEN
595 for a quotient (stored in *LQUO, *HQUO) and remainder (in *LREM, *HREM).
596 CODE is a tree code for a kind of division, one of
597 TRUNC_DIV_EXPR, FLOOR_DIV_EXPR, CEIL_DIV_EXPR, ROUND_DIV_EXPR
599 It controls how the quotient is rounded to an integer.
600 Return nonzero if the operation overflows.
601 UNS nonzero says do unsigned division. */
604 div_and_round_double (enum tree_code code, int uns,
605 unsigned HOST_WIDE_INT lnum_orig, /* num == numerator == dividend */
606 HOST_WIDE_INT hnum_orig,
607 unsigned HOST_WIDE_INT lden_orig, /* den == denominator == divisor */
608 HOST_WIDE_INT hden_orig,
609 unsigned HOST_WIDE_INT *lquo,
610 HOST_WIDE_INT *hquo, unsigned HOST_WIDE_INT *lrem,
614 HOST_WIDE_INT num[4 + 1]; /* extra element for scaling. */
615 HOST_WIDE_INT den[4], quo[4];
617 unsigned HOST_WIDE_INT work;
618 unsigned HOST_WIDE_INT carry = 0;
619 unsigned HOST_WIDE_INT lnum = lnum_orig;
620 HOST_WIDE_INT hnum = hnum_orig;
621 unsigned HOST_WIDE_INT lden = lden_orig;
622 HOST_WIDE_INT hden = hden_orig;
625 if (hden == 0 && lden == 0)
626 overflow = 1, lden = 1;
628 /* Calculate quotient sign and convert operands to unsigned. */
634 /* (minimum integer) / (-1) is the only overflow case. */
635 if (neg_double (lnum, hnum, &lnum, &hnum)
636 && ((HOST_WIDE_INT) lden & hden) == -1)
642 neg_double (lden, hden, &lden, &hden);
646 if (hnum == 0 && hden == 0)
647 { /* single precision */
649 /* This unsigned division rounds toward zero. */
655 { /* trivial case: dividend < divisor */
656 /* hden != 0 already checked. */
663 memset (quo, 0, sizeof quo);
665 memset (num, 0, sizeof num); /* to zero 9th element */
666 memset (den, 0, sizeof den);
668 encode (num, lnum, hnum);
669 encode (den, lden, hden);
671 /* Special code for when the divisor < BASE. */
672 if (hden == 0 && lden < (unsigned HOST_WIDE_INT) BASE)
674 /* hnum != 0 already checked. */
675 for (i = 4 - 1; i >= 0; i--)
677 work = num[i] + carry * BASE;
678 quo[i] = work / lden;
684 /* Full double precision division,
685 with thanks to Don Knuth's "Seminumerical Algorithms". */
686 int num_hi_sig, den_hi_sig;
687 unsigned HOST_WIDE_INT quo_est, scale;
689 /* Find the highest nonzero divisor digit. */
690 for (i = 4 - 1;; i--)
697 /* Insure that the first digit of the divisor is at least BASE/2.
698 This is required by the quotient digit estimation algorithm. */
700 scale = BASE / (den[den_hi_sig] + 1);
702 { /* scale divisor and dividend */
704 for (i = 0; i <= 4 - 1; i++)
706 work = (num[i] * scale) + carry;
707 num[i] = LOWPART (work);
708 carry = HIGHPART (work);
713 for (i = 0; i <= 4 - 1; i++)
715 work = (den[i] * scale) + carry;
716 den[i] = LOWPART (work);
717 carry = HIGHPART (work);
718 if (den[i] != 0) den_hi_sig = i;
725 for (i = num_hi_sig - den_hi_sig - 1; i >= 0; i--)
727 /* Guess the next quotient digit, quo_est, by dividing the first
728 two remaining dividend digits by the high order quotient digit.
729 quo_est is never low and is at most 2 high. */
730 unsigned HOST_WIDE_INT tmp;
732 num_hi_sig = i + den_hi_sig + 1;
733 work = num[num_hi_sig] * BASE + num[num_hi_sig - 1];
734 if (num[num_hi_sig] != den[den_hi_sig])
735 quo_est = work / den[den_hi_sig];
739 /* Refine quo_est so it's usually correct, and at most one high. */
740 tmp = work - quo_est * den[den_hi_sig];
742 && (den[den_hi_sig - 1] * quo_est
743 > (tmp * BASE + num[num_hi_sig - 2])))
746 /* Try QUO_EST as the quotient digit, by multiplying the
747 divisor by QUO_EST and subtracting from the remaining dividend.
748 Keep in mind that QUO_EST is the I - 1st digit. */
751 for (j = 0; j <= den_hi_sig; j++)
753 work = quo_est * den[j] + carry;
754 carry = HIGHPART (work);
755 work = num[i + j] - LOWPART (work);
756 num[i + j] = LOWPART (work);
757 carry += HIGHPART (work) != 0;
760 /* If quo_est was high by one, then num[i] went negative and
761 we need to correct things. */
762 if (num[num_hi_sig] < (HOST_WIDE_INT) carry)
765 carry = 0; /* add divisor back in */
766 for (j = 0; j <= den_hi_sig; j++)
768 work = num[i + j] + den[j] + carry;
769 carry = HIGHPART (work);
770 num[i + j] = LOWPART (work);
773 num [num_hi_sig] += carry;
776 /* Store the quotient digit. */
781 decode (quo, lquo, hquo);
784 /* If result is negative, make it so. */
786 neg_double (*lquo, *hquo, lquo, hquo);
788 /* Compute trial remainder: rem = num - (quo * den) */
789 mul_double (*lquo, *hquo, lden_orig, hden_orig, lrem, hrem);
790 neg_double (*lrem, *hrem, lrem, hrem);
791 add_double (lnum_orig, hnum_orig, *lrem, *hrem, lrem, hrem);
796 case TRUNC_MOD_EXPR: /* round toward zero */
797 case EXACT_DIV_EXPR: /* for this one, it shouldn't matter */
801 case FLOOR_MOD_EXPR: /* round toward negative infinity */
802 if (quo_neg && (*lrem != 0 || *hrem != 0)) /* ratio < 0 && rem != 0 */
805 add_double (*lquo, *hquo, (HOST_WIDE_INT) -1, (HOST_WIDE_INT) -1,
813 case CEIL_MOD_EXPR: /* round toward positive infinity */
814 if (!quo_neg && (*lrem != 0 || *hrem != 0)) /* ratio > 0 && rem != 0 */
816 add_double (*lquo, *hquo, (HOST_WIDE_INT) 1, (HOST_WIDE_INT) 0,
824 case ROUND_MOD_EXPR: /* round to closest integer */
826 unsigned HOST_WIDE_INT labs_rem = *lrem;
827 HOST_WIDE_INT habs_rem = *hrem;
828 unsigned HOST_WIDE_INT labs_den = lden, ltwice;
829 HOST_WIDE_INT habs_den = hden, htwice;
831 /* Get absolute values. */
833 neg_double (*lrem, *hrem, &labs_rem, &habs_rem);
835 neg_double (lden, hden, &labs_den, &habs_den);
837 /* If (2 * abs (lrem) >= abs (lden)) */
838 mul_double ((HOST_WIDE_INT) 2, (HOST_WIDE_INT) 0,
839 labs_rem, habs_rem, <wice, &htwice);
841 if (((unsigned HOST_WIDE_INT) habs_den
842 < (unsigned HOST_WIDE_INT) htwice)
843 || (((unsigned HOST_WIDE_INT) habs_den
844 == (unsigned HOST_WIDE_INT) htwice)
845 && (labs_den < ltwice)))
849 add_double (*lquo, *hquo,
850 (HOST_WIDE_INT) -1, (HOST_WIDE_INT) -1, lquo, hquo);
853 add_double (*lquo, *hquo, (HOST_WIDE_INT) 1, (HOST_WIDE_INT) 0,
865 /* Compute true remainder: rem = num - (quo * den) */
866 mul_double (*lquo, *hquo, lden_orig, hden_orig, lrem, hrem);
867 neg_double (*lrem, *hrem, lrem, hrem);
868 add_double (lnum_orig, hnum_orig, *lrem, *hrem, lrem, hrem);
872 /* If ARG2 divides ARG1 with zero remainder, carries out the division
873 of type CODE and returns the quotient.
874 Otherwise returns NULL_TREE. */
877 div_if_zero_remainder (enum tree_code code, const_tree arg1, const_tree arg2)
879 unsigned HOST_WIDE_INT int1l, int2l;
880 HOST_WIDE_INT int1h, int2h;
881 unsigned HOST_WIDE_INT quol, reml;
882 HOST_WIDE_INT quoh, remh;
883 tree type = TREE_TYPE (arg1);
884 int uns = TYPE_UNSIGNED (type);
886 int1l = TREE_INT_CST_LOW (arg1);
887 int1h = TREE_INT_CST_HIGH (arg1);
888 /* &obj[0] + -128 really should be compiled as &obj[-8] rather than
889 &obj[some_exotic_number]. */
890 if (POINTER_TYPE_P (type))
893 type = signed_type_for (type);
894 fit_double_type (int1l, int1h, &int1l, &int1h,
898 fit_double_type (int1l, int1h, &int1l, &int1h, type);
899 int2l = TREE_INT_CST_LOW (arg2);
900 int2h = TREE_INT_CST_HIGH (arg2);
902 div_and_round_double (code, uns, int1l, int1h, int2l, int2h,
903 &quol, &quoh, &reml, &remh);
904 if (remh != 0 || reml != 0)
907 return build_int_cst_wide (type, quol, quoh);
910 /* This is nonzero if we should defer warnings about undefined
911 overflow. This facility exists because these warnings are a
912 special case. The code to estimate loop iterations does not want
913 to issue any warnings, since it works with expressions which do not
914 occur in user code. Various bits of cleanup code call fold(), but
915 only use the result if it has certain characteristics (e.g., is a
916 constant); that code only wants to issue a warning if the result is
919 static int fold_deferring_overflow_warnings;
921 /* If a warning about undefined overflow is deferred, this is the
922 warning. Note that this may cause us to turn two warnings into
923 one, but that is fine since it is sufficient to only give one
924 warning per expression. */
926 static const char* fold_deferred_overflow_warning;
928 /* If a warning about undefined overflow is deferred, this is the
929 level at which the warning should be emitted. */
931 static enum warn_strict_overflow_code fold_deferred_overflow_code;
933 /* Start deferring overflow warnings. We could use a stack here to
934 permit nested calls, but at present it is not necessary. */
937 fold_defer_overflow_warnings (void)
939 ++fold_deferring_overflow_warnings;
942 /* Stop deferring overflow warnings. If there is a pending warning,
943 and ISSUE is true, then issue the warning if appropriate. STMT is
944 the statement with which the warning should be associated (used for
945 location information); STMT may be NULL. CODE is the level of the
946 warning--a warn_strict_overflow_code value. This function will use
947 the smaller of CODE and the deferred code when deciding whether to
948 issue the warning. CODE may be zero to mean to always use the
952 fold_undefer_overflow_warnings (bool issue, const_tree stmt, int code)
957 gcc_assert (fold_deferring_overflow_warnings > 0);
958 --fold_deferring_overflow_warnings;
959 if (fold_deferring_overflow_warnings > 0)
961 if (fold_deferred_overflow_warning != NULL
963 && code < (int) fold_deferred_overflow_code)
964 fold_deferred_overflow_code = code;
968 warnmsg = fold_deferred_overflow_warning;
969 fold_deferred_overflow_warning = NULL;
971 if (!issue || warnmsg == NULL)
974 if (stmt != NULL_TREE && TREE_NO_WARNING (stmt))
977 /* Use the smallest code level when deciding to issue the
979 if (code == 0 || code > (int) fold_deferred_overflow_code)
980 code = fold_deferred_overflow_code;
982 if (!issue_strict_overflow_warning (code))
985 if (stmt == NULL_TREE || !expr_has_location (stmt))
986 locus = input_location;
988 locus = expr_location (stmt);
989 warning (OPT_Wstrict_overflow, "%H%s", &locus, warnmsg);
992 /* Stop deferring overflow warnings, ignoring any deferred
996 fold_undefer_and_ignore_overflow_warnings (void)
998 fold_undefer_overflow_warnings (false, NULL_TREE, 0);
1001 /* Whether we are deferring overflow warnings. */
1004 fold_deferring_overflow_warnings_p (void)
1006 return fold_deferring_overflow_warnings > 0;
1009 /* This is called when we fold something based on the fact that signed
1010 overflow is undefined. */
1013 fold_overflow_warning (const char* gmsgid, enum warn_strict_overflow_code wc)
1015 if (fold_deferring_overflow_warnings > 0)
1017 if (fold_deferred_overflow_warning == NULL
1018 || wc < fold_deferred_overflow_code)
1020 fold_deferred_overflow_warning = gmsgid;
1021 fold_deferred_overflow_code = wc;
1024 else if (issue_strict_overflow_warning (wc))
1025 warning (OPT_Wstrict_overflow, gmsgid);
1028 /* Return true if the built-in mathematical function specified by CODE
1029 is odd, i.e. -f(x) == f(-x). */
1032 negate_mathfn_p (enum built_in_function code)
1036 CASE_FLT_FN (BUILT_IN_ASIN):
1037 CASE_FLT_FN (BUILT_IN_ASINH):
1038 CASE_FLT_FN (BUILT_IN_ATAN):
1039 CASE_FLT_FN (BUILT_IN_ATANH):
1040 CASE_FLT_FN (BUILT_IN_CASIN):
1041 CASE_FLT_FN (BUILT_IN_CASINH):
1042 CASE_FLT_FN (BUILT_IN_CATAN):
1043 CASE_FLT_FN (BUILT_IN_CATANH):
1044 CASE_FLT_FN (BUILT_IN_CBRT):
1045 CASE_FLT_FN (BUILT_IN_CPROJ):
1046 CASE_FLT_FN (BUILT_IN_CSIN):
1047 CASE_FLT_FN (BUILT_IN_CSINH):
1048 CASE_FLT_FN (BUILT_IN_CTAN):
1049 CASE_FLT_FN (BUILT_IN_CTANH):
1050 CASE_FLT_FN (BUILT_IN_ERF):
1051 CASE_FLT_FN (BUILT_IN_LLROUND):
1052 CASE_FLT_FN (BUILT_IN_LROUND):
1053 CASE_FLT_FN (BUILT_IN_ROUND):
1054 CASE_FLT_FN (BUILT_IN_SIN):
1055 CASE_FLT_FN (BUILT_IN_SINH):
1056 CASE_FLT_FN (BUILT_IN_TAN):
1057 CASE_FLT_FN (BUILT_IN_TANH):
1058 CASE_FLT_FN (BUILT_IN_TRUNC):
1061 CASE_FLT_FN (BUILT_IN_LLRINT):
1062 CASE_FLT_FN (BUILT_IN_LRINT):
1063 CASE_FLT_FN (BUILT_IN_NEARBYINT):
1064 CASE_FLT_FN (BUILT_IN_RINT):
1065 return !flag_rounding_math;
1073 /* Check whether we may negate an integer constant T without causing
1077 may_negate_without_overflow_p (const_tree t)
1079 unsigned HOST_WIDE_INT val;
1083 gcc_assert (TREE_CODE (t) == INTEGER_CST);
1085 type = TREE_TYPE (t);
1086 if (TYPE_UNSIGNED (type))
1089 prec = TYPE_PRECISION (type);
1090 if (prec > HOST_BITS_PER_WIDE_INT)
1092 if (TREE_INT_CST_LOW (t) != 0)
1094 prec -= HOST_BITS_PER_WIDE_INT;
1095 val = TREE_INT_CST_HIGH (t);
1098 val = TREE_INT_CST_LOW (t);
1099 if (prec < HOST_BITS_PER_WIDE_INT)
1100 val &= ((unsigned HOST_WIDE_INT) 1 << prec) - 1;
1101 return val != ((unsigned HOST_WIDE_INT) 1 << (prec - 1));
1104 /* Determine whether an expression T can be cheaply negated using
1105 the function negate_expr without introducing undefined overflow. */
1108 negate_expr_p (tree t)
1115 type = TREE_TYPE (t);
1117 STRIP_SIGN_NOPS (t);
1118 switch (TREE_CODE (t))
1121 if (TYPE_OVERFLOW_WRAPS (type))
1124 /* Check that -CST will not overflow type. */
1125 return may_negate_without_overflow_p (t);
1127 return (INTEGRAL_TYPE_P (type)
1128 && TYPE_OVERFLOW_WRAPS (type));
1136 return negate_expr_p (TREE_REALPART (t))
1137 && negate_expr_p (TREE_IMAGPART (t));
1140 return negate_expr_p (TREE_OPERAND (t, 0))
1141 && negate_expr_p (TREE_OPERAND (t, 1));
1144 return negate_expr_p (TREE_OPERAND (t, 0));
1147 if (HONOR_SIGN_DEPENDENT_ROUNDING (TYPE_MODE (type))
1148 || HONOR_SIGNED_ZEROS (TYPE_MODE (type)))
1150 /* -(A + B) -> (-B) - A. */
1151 if (negate_expr_p (TREE_OPERAND (t, 1))
1152 && reorder_operands_p (TREE_OPERAND (t, 0),
1153 TREE_OPERAND (t, 1)))
1155 /* -(A + B) -> (-A) - B. */
1156 return negate_expr_p (TREE_OPERAND (t, 0));
1159 /* We can't turn -(A-B) into B-A when we honor signed zeros. */
1160 return !HONOR_SIGN_DEPENDENT_ROUNDING (TYPE_MODE (type))
1161 && !HONOR_SIGNED_ZEROS (TYPE_MODE (type))
1162 && reorder_operands_p (TREE_OPERAND (t, 0),
1163 TREE_OPERAND (t, 1));
1166 if (TYPE_UNSIGNED (TREE_TYPE (t)))
1172 if (! HONOR_SIGN_DEPENDENT_ROUNDING (TYPE_MODE (TREE_TYPE (t))))
1173 return negate_expr_p (TREE_OPERAND (t, 1))
1174 || negate_expr_p (TREE_OPERAND (t, 0));
1177 case TRUNC_DIV_EXPR:
1178 case ROUND_DIV_EXPR:
1179 case FLOOR_DIV_EXPR:
1181 case EXACT_DIV_EXPR:
1182 /* In general we can't negate A / B, because if A is INT_MIN and
1183 B is 1, we may turn this into INT_MIN / -1 which is undefined
1184 and actually traps on some architectures. But if overflow is
1185 undefined, we can negate, because - (INT_MIN / 1) is an
1187 if (INTEGRAL_TYPE_P (TREE_TYPE (t))
1188 && !TYPE_OVERFLOW_UNDEFINED (TREE_TYPE (t)))
1190 return negate_expr_p (TREE_OPERAND (t, 1))
1191 || negate_expr_p (TREE_OPERAND (t, 0));
1194 /* Negate -((double)float) as (double)(-float). */
1195 if (TREE_CODE (type) == REAL_TYPE)
1197 tree tem = strip_float_extensions (t);
1199 return negate_expr_p (tem);
1204 /* Negate -f(x) as f(-x). */
1205 if (negate_mathfn_p (builtin_mathfn_code (t)))
1206 return negate_expr_p (CALL_EXPR_ARG (t, 0));
1210 /* Optimize -((int)x >> 31) into (unsigned)x >> 31. */
1211 if (TREE_CODE (TREE_OPERAND (t, 1)) == INTEGER_CST)
1213 tree op1 = TREE_OPERAND (t, 1);
1214 if (TREE_INT_CST_HIGH (op1) == 0
1215 && (unsigned HOST_WIDE_INT) (TYPE_PRECISION (type) - 1)
1216 == TREE_INT_CST_LOW (op1))
1227 /* Given T, an expression, return a folded tree for -T or NULL_TREE, if no
1228 simplification is possible.
1229 If negate_expr_p would return true for T, NULL_TREE will never be
1233 fold_negate_expr (tree t)
1235 tree type = TREE_TYPE (t);
1238 switch (TREE_CODE (t))
1240 /* Convert - (~A) to A + 1. */
1242 if (INTEGRAL_TYPE_P (type))
1243 return fold_build2 (PLUS_EXPR, type, TREE_OPERAND (t, 0),
1244 build_int_cst (type, 1));
1248 tem = fold_negate_const (t, type);
1249 if (TREE_OVERFLOW (tem) == TREE_OVERFLOW (t)
1250 || !TYPE_OVERFLOW_TRAPS (type))
1255 tem = fold_negate_const (t, type);
1256 /* Two's complement FP formats, such as c4x, may overflow. */
1257 if (!TREE_OVERFLOW (tem) || !flag_trapping_math)
1262 tem = fold_negate_const (t, type);
1267 tree rpart = negate_expr (TREE_REALPART (t));
1268 tree ipart = negate_expr (TREE_IMAGPART (t));
1270 if ((TREE_CODE (rpart) == REAL_CST
1271 && TREE_CODE (ipart) == REAL_CST)
1272 || (TREE_CODE (rpart) == INTEGER_CST
1273 && TREE_CODE (ipart) == INTEGER_CST))
1274 return build_complex (type, rpart, ipart);
1279 if (negate_expr_p (t))
1280 return fold_build2 (COMPLEX_EXPR, type,
1281 fold_negate_expr (TREE_OPERAND (t, 0)),
1282 fold_negate_expr (TREE_OPERAND (t, 1)));
1286 if (negate_expr_p (t))
1287 return fold_build1 (CONJ_EXPR, type,
1288 fold_negate_expr (TREE_OPERAND (t, 0)));
1292 return TREE_OPERAND (t, 0);
1295 if (!HONOR_SIGN_DEPENDENT_ROUNDING (TYPE_MODE (type))
1296 && !HONOR_SIGNED_ZEROS (TYPE_MODE (type)))
1298 /* -(A + B) -> (-B) - A. */
1299 if (negate_expr_p (TREE_OPERAND (t, 1))
1300 && reorder_operands_p (TREE_OPERAND (t, 0),
1301 TREE_OPERAND (t, 1)))
1303 tem = negate_expr (TREE_OPERAND (t, 1));
1304 return fold_build2 (MINUS_EXPR, type,
1305 tem, TREE_OPERAND (t, 0));
1308 /* -(A + B) -> (-A) - B. */
1309 if (negate_expr_p (TREE_OPERAND (t, 0)))
1311 tem = negate_expr (TREE_OPERAND (t, 0));
1312 return fold_build2 (MINUS_EXPR, type,
1313 tem, TREE_OPERAND (t, 1));
1319 /* - (A - B) -> B - A */
1320 if (!HONOR_SIGN_DEPENDENT_ROUNDING (TYPE_MODE (type))
1321 && !HONOR_SIGNED_ZEROS (TYPE_MODE (type))
1322 && reorder_operands_p (TREE_OPERAND (t, 0), TREE_OPERAND (t, 1)))
1323 return fold_build2 (MINUS_EXPR, type,
1324 TREE_OPERAND (t, 1), TREE_OPERAND (t, 0));
1328 if (TYPE_UNSIGNED (type))
1334 if (! HONOR_SIGN_DEPENDENT_ROUNDING (TYPE_MODE (type)))
1336 tem = TREE_OPERAND (t, 1);
1337 if (negate_expr_p (tem))
1338 return fold_build2 (TREE_CODE (t), type,
1339 TREE_OPERAND (t, 0), negate_expr (tem));
1340 tem = TREE_OPERAND (t, 0);
1341 if (negate_expr_p (tem))
1342 return fold_build2 (TREE_CODE (t), type,
1343 negate_expr (tem), TREE_OPERAND (t, 1));
1347 case TRUNC_DIV_EXPR:
1348 case ROUND_DIV_EXPR:
1349 case FLOOR_DIV_EXPR:
1351 case EXACT_DIV_EXPR:
1352 /* In general we can't negate A / B, because if A is INT_MIN and
1353 B is 1, we may turn this into INT_MIN / -1 which is undefined
1354 and actually traps on some architectures. But if overflow is
1355 undefined, we can negate, because - (INT_MIN / 1) is an
1357 if (!INTEGRAL_TYPE_P (type) || TYPE_OVERFLOW_UNDEFINED (type))
1359 const char * const warnmsg = G_("assuming signed overflow does not "
1360 "occur when negating a division");
1361 tem = TREE_OPERAND (t, 1);
1362 if (negate_expr_p (tem))
1364 if (INTEGRAL_TYPE_P (type)
1365 && (TREE_CODE (tem) != INTEGER_CST
1366 || integer_onep (tem)))
1367 fold_overflow_warning (warnmsg, WARN_STRICT_OVERFLOW_MISC);
1368 return fold_build2 (TREE_CODE (t), type,
1369 TREE_OPERAND (t, 0), negate_expr (tem));
1371 tem = TREE_OPERAND (t, 0);
1372 if (negate_expr_p (tem))
1374 if (INTEGRAL_TYPE_P (type)
1375 && (TREE_CODE (tem) != INTEGER_CST
1376 || tree_int_cst_equal (tem, TYPE_MIN_VALUE (type))))
1377 fold_overflow_warning (warnmsg, WARN_STRICT_OVERFLOW_MISC);
1378 return fold_build2 (TREE_CODE (t), type,
1379 negate_expr (tem), TREE_OPERAND (t, 1));
1385 /* Convert -((double)float) into (double)(-float). */
1386 if (TREE_CODE (type) == REAL_TYPE)
1388 tem = strip_float_extensions (t);
1389 if (tem != t && negate_expr_p (tem))
1390 return fold_convert (type, negate_expr (tem));
1395 /* Negate -f(x) as f(-x). */
1396 if (negate_mathfn_p (builtin_mathfn_code (t))
1397 && negate_expr_p (CALL_EXPR_ARG (t, 0)))
1401 fndecl = get_callee_fndecl (t);
1402 arg = negate_expr (CALL_EXPR_ARG (t, 0));
1403 return build_call_expr (fndecl, 1, arg);
1408 /* Optimize -((int)x >> 31) into (unsigned)x >> 31. */
1409 if (TREE_CODE (TREE_OPERAND (t, 1)) == INTEGER_CST)
1411 tree op1 = TREE_OPERAND (t, 1);
1412 if (TREE_INT_CST_HIGH (op1) == 0
1413 && (unsigned HOST_WIDE_INT) (TYPE_PRECISION (type) - 1)
1414 == TREE_INT_CST_LOW (op1))
1416 tree ntype = TYPE_UNSIGNED (type)
1417 ? signed_type_for (type)
1418 : unsigned_type_for (type);
1419 tree temp = fold_convert (ntype, TREE_OPERAND (t, 0));
1420 temp = fold_build2 (RSHIFT_EXPR, ntype, temp, op1);
1421 return fold_convert (type, temp);
1433 /* Like fold_negate_expr, but return a NEGATE_EXPR tree, if T can not be
1434 negated in a simpler way. Also allow for T to be NULL_TREE, in which case
1435 return NULL_TREE. */
1438 negate_expr (tree t)
1445 type = TREE_TYPE (t);
1446 STRIP_SIGN_NOPS (t);
1448 tem = fold_negate_expr (t);
1450 tem = build1 (NEGATE_EXPR, TREE_TYPE (t), t);
1451 return fold_convert (type, tem);
1454 /* Split a tree IN into a constant, literal and variable parts that could be
1455 combined with CODE to make IN. "constant" means an expression with
1456 TREE_CONSTANT but that isn't an actual constant. CODE must be a
1457 commutative arithmetic operation. Store the constant part into *CONP,
1458 the literal in *LITP and return the variable part. If a part isn't
1459 present, set it to null. If the tree does not decompose in this way,
1460 return the entire tree as the variable part and the other parts as null.
1462 If CODE is PLUS_EXPR we also split trees that use MINUS_EXPR. In that
1463 case, we negate an operand that was subtracted. Except if it is a
1464 literal for which we use *MINUS_LITP instead.
1466 If NEGATE_P is true, we are negating all of IN, again except a literal
1467 for which we use *MINUS_LITP instead.
1469 If IN is itself a literal or constant, return it as appropriate.
1471 Note that we do not guarantee that any of the three values will be the
1472 same type as IN, but they will have the same signedness and mode. */
1475 split_tree (tree in, enum tree_code code, tree *conp, tree *litp,
1476 tree *minus_litp, int negate_p)
1484 /* Strip any conversions that don't change the machine mode or signedness. */
1485 STRIP_SIGN_NOPS (in);
1487 if (TREE_CODE (in) == INTEGER_CST || TREE_CODE (in) == REAL_CST
1488 || TREE_CODE (in) == FIXED_CST)
1490 else if (TREE_CODE (in) == code
1491 || ((! FLOAT_TYPE_P (TREE_TYPE (in)) || flag_associative_math)
1492 && ! SAT_FIXED_POINT_TYPE_P (TREE_TYPE (in))
1493 /* We can associate addition and subtraction together (even
1494 though the C standard doesn't say so) for integers because
1495 the value is not affected. For reals, the value might be
1496 affected, so we can't. */
1497 && ((code == PLUS_EXPR && TREE_CODE (in) == MINUS_EXPR)
1498 || (code == MINUS_EXPR && TREE_CODE (in) == PLUS_EXPR))))
1500 tree op0 = TREE_OPERAND (in, 0);
1501 tree op1 = TREE_OPERAND (in, 1);
1502 int neg1_p = TREE_CODE (in) == MINUS_EXPR;
1503 int neg_litp_p = 0, neg_conp_p = 0, neg_var_p = 0;
1505 /* First see if either of the operands is a literal, then a constant. */
1506 if (TREE_CODE (op0) == INTEGER_CST || TREE_CODE (op0) == REAL_CST
1507 || TREE_CODE (op0) == FIXED_CST)
1508 *litp = op0, op0 = 0;
1509 else if (TREE_CODE (op1) == INTEGER_CST || TREE_CODE (op1) == REAL_CST
1510 || TREE_CODE (op1) == FIXED_CST)
1511 *litp = op1, neg_litp_p = neg1_p, op1 = 0;
1513 if (op0 != 0 && TREE_CONSTANT (op0))
1514 *conp = op0, op0 = 0;
1515 else if (op1 != 0 && TREE_CONSTANT (op1))
1516 *conp = op1, neg_conp_p = neg1_p, op1 = 0;
1518 /* If we haven't dealt with either operand, this is not a case we can
1519 decompose. Otherwise, VAR is either of the ones remaining, if any. */
1520 if (op0 != 0 && op1 != 0)
1525 var = op1, neg_var_p = neg1_p;
1527 /* Now do any needed negations. */
1529 *minus_litp = *litp, *litp = 0;
1531 *conp = negate_expr (*conp);
1533 var = negate_expr (var);
1535 else if (TREE_CONSTANT (in))
1543 *minus_litp = *litp, *litp = 0;
1544 else if (*minus_litp)
1545 *litp = *minus_litp, *minus_litp = 0;
1546 *conp = negate_expr (*conp);
1547 var = negate_expr (var);
1553 /* Re-associate trees split by the above function. T1 and T2 are either
1554 expressions to associate or null. Return the new expression, if any. If
1555 we build an operation, do it in TYPE and with CODE. */
1558 associate_trees (tree t1, tree t2, enum tree_code code, tree type)
1565 /* If either input is CODE, a PLUS_EXPR, or a MINUS_EXPR, don't
1566 try to fold this since we will have infinite recursion. But do
1567 deal with any NEGATE_EXPRs. */
1568 if (TREE_CODE (t1) == code || TREE_CODE (t2) == code
1569 || TREE_CODE (t1) == MINUS_EXPR || TREE_CODE (t2) == MINUS_EXPR)
1571 if (code == PLUS_EXPR)
1573 if (TREE_CODE (t1) == NEGATE_EXPR)
1574 return build2 (MINUS_EXPR, type, fold_convert (type, t2),
1575 fold_convert (type, TREE_OPERAND (t1, 0)));
1576 else if (TREE_CODE (t2) == NEGATE_EXPR)
1577 return build2 (MINUS_EXPR, type, fold_convert (type, t1),
1578 fold_convert (type, TREE_OPERAND (t2, 0)));
1579 else if (integer_zerop (t2))
1580 return fold_convert (type, t1);
1582 else if (code == MINUS_EXPR)
1584 if (integer_zerop (t2))
1585 return fold_convert (type, t1);
1588 return build2 (code, type, fold_convert (type, t1),
1589 fold_convert (type, t2));
1592 return fold_build2 (code, type, fold_convert (type, t1),
1593 fold_convert (type, t2));
1596 /* Check whether TYPE1 and TYPE2 are equivalent integer types, suitable
1597 for use in int_const_binop, size_binop and size_diffop. */
1600 int_binop_types_match_p (enum tree_code code, const_tree type1, const_tree type2)
1602 if (TREE_CODE (type1) != INTEGER_TYPE && !POINTER_TYPE_P (type1))
1604 if (TREE_CODE (type2) != INTEGER_TYPE && !POINTER_TYPE_P (type2))
1619 return TYPE_UNSIGNED (type1) == TYPE_UNSIGNED (type2)
1620 && TYPE_PRECISION (type1) == TYPE_PRECISION (type2)
1621 && TYPE_MODE (type1) == TYPE_MODE (type2);
1625 /* Combine two integer constants ARG1 and ARG2 under operation CODE
1626 to produce a new constant. Return NULL_TREE if we don't know how
1627 to evaluate CODE at compile-time.
1629 If NOTRUNC is nonzero, do not truncate the result to fit the data type. */
1632 int_const_binop (enum tree_code code, const_tree arg1, const_tree arg2, int notrunc)
1634 unsigned HOST_WIDE_INT int1l, int2l;
1635 HOST_WIDE_INT int1h, int2h;
1636 unsigned HOST_WIDE_INT low;
1638 unsigned HOST_WIDE_INT garbagel;
1639 HOST_WIDE_INT garbageh;
1641 tree type = TREE_TYPE (arg1);
1642 int uns = TYPE_UNSIGNED (type);
1644 = (TREE_CODE (type) == INTEGER_TYPE && TYPE_IS_SIZETYPE (type));
1647 int1l = TREE_INT_CST_LOW (arg1);
1648 int1h = TREE_INT_CST_HIGH (arg1);
1649 int2l = TREE_INT_CST_LOW (arg2);
1650 int2h = TREE_INT_CST_HIGH (arg2);
1655 low = int1l | int2l, hi = int1h | int2h;
1659 low = int1l ^ int2l, hi = int1h ^ int2h;
1663 low = int1l & int2l, hi = int1h & int2h;
1669 /* It's unclear from the C standard whether shifts can overflow.
1670 The following code ignores overflow; perhaps a C standard
1671 interpretation ruling is needed. */
1672 lshift_double (int1l, int1h, int2l, TYPE_PRECISION (type),
1679 lrotate_double (int1l, int1h, int2l, TYPE_PRECISION (type),
1684 overflow = add_double (int1l, int1h, int2l, int2h, &low, &hi);
1688 neg_double (int2l, int2h, &low, &hi);
1689 add_double (int1l, int1h, low, hi, &low, &hi);
1690 overflow = OVERFLOW_SUM_SIGN (hi, int2h, int1h);
1694 overflow = mul_double (int1l, int1h, int2l, int2h, &low, &hi);
1697 case TRUNC_DIV_EXPR:
1698 case FLOOR_DIV_EXPR: case CEIL_DIV_EXPR:
1699 case EXACT_DIV_EXPR:
1700 /* This is a shortcut for a common special case. */
1701 if (int2h == 0 && (HOST_WIDE_INT) int2l > 0
1702 && !TREE_OVERFLOW (arg1)
1703 && !TREE_OVERFLOW (arg2)
1704 && int1h == 0 && (HOST_WIDE_INT) int1l >= 0)
1706 if (code == CEIL_DIV_EXPR)
1709 low = int1l / int2l, hi = 0;
1713 /* ... fall through ... */
1715 case ROUND_DIV_EXPR:
1716 if (int2h == 0 && int2l == 0)
1718 if (int2h == 0 && int2l == 1)
1720 low = int1l, hi = int1h;
1723 if (int1l == int2l && int1h == int2h
1724 && ! (int1l == 0 && int1h == 0))
1729 overflow = div_and_round_double (code, uns, int1l, int1h, int2l, int2h,
1730 &low, &hi, &garbagel, &garbageh);
1733 case TRUNC_MOD_EXPR:
1734 case FLOOR_MOD_EXPR: case CEIL_MOD_EXPR:
1735 /* This is a shortcut for a common special case. */
1736 if (int2h == 0 && (HOST_WIDE_INT) int2l > 0
1737 && !TREE_OVERFLOW (arg1)
1738 && !TREE_OVERFLOW (arg2)
1739 && int1h == 0 && (HOST_WIDE_INT) int1l >= 0)
1741 if (code == CEIL_MOD_EXPR)
1743 low = int1l % int2l, hi = 0;
1747 /* ... fall through ... */
1749 case ROUND_MOD_EXPR:
1750 if (int2h == 0 && int2l == 0)
1752 overflow = div_and_round_double (code, uns,
1753 int1l, int1h, int2l, int2h,
1754 &garbagel, &garbageh, &low, &hi);
1760 low = (((unsigned HOST_WIDE_INT) int1h
1761 < (unsigned HOST_WIDE_INT) int2h)
1762 || (((unsigned HOST_WIDE_INT) int1h
1763 == (unsigned HOST_WIDE_INT) int2h)
1766 low = (int1h < int2h
1767 || (int1h == int2h && int1l < int2l));
1769 if (low == (code == MIN_EXPR))
1770 low = int1l, hi = int1h;
1772 low = int2l, hi = int2h;
1781 t = build_int_cst_wide (TREE_TYPE (arg1), low, hi);
1783 /* Propagate overflow flags ourselves. */
1784 if (((!uns || is_sizetype) && overflow)
1785 | TREE_OVERFLOW (arg1) | TREE_OVERFLOW (arg2))
1788 TREE_OVERFLOW (t) = 1;
1792 t = force_fit_type_double (TREE_TYPE (arg1), low, hi, 1,
1793 ((!uns || is_sizetype) && overflow)
1794 | TREE_OVERFLOW (arg1) | TREE_OVERFLOW (arg2));
1799 /* Combine two constants ARG1 and ARG2 under operation CODE to produce a new
1800 constant. We assume ARG1 and ARG2 have the same data type, or at least
1801 are the same kind of constant and the same machine mode. Return zero if
1802 combining the constants is not allowed in the current operating mode.
1804 If NOTRUNC is nonzero, do not truncate the result to fit the data type. */
1807 const_binop (enum tree_code code, tree arg1, tree arg2, int notrunc)
1809 /* Sanity check for the recursive cases. */
1816 if (TREE_CODE (arg1) == INTEGER_CST)
1817 return int_const_binop (code, arg1, arg2, notrunc);
1819 if (TREE_CODE (arg1) == REAL_CST)
1821 enum machine_mode mode;
1824 REAL_VALUE_TYPE value;
1825 REAL_VALUE_TYPE result;
1829 /* The following codes are handled by real_arithmetic. */
1844 d1 = TREE_REAL_CST (arg1);
1845 d2 = TREE_REAL_CST (arg2);
1847 type = TREE_TYPE (arg1);
1848 mode = TYPE_MODE (type);
1850 /* Don't perform operation if we honor signaling NaNs and
1851 either operand is a NaN. */
1852 if (HONOR_SNANS (mode)
1853 && (REAL_VALUE_ISNAN (d1) || REAL_VALUE_ISNAN (d2)))
1856 /* Don't perform operation if it would raise a division
1857 by zero exception. */
1858 if (code == RDIV_EXPR
1859 && REAL_VALUES_EQUAL (d2, dconst0)
1860 && (flag_trapping_math || ! MODE_HAS_INFINITIES (mode)))
1863 /* If either operand is a NaN, just return it. Otherwise, set up
1864 for floating-point trap; we return an overflow. */
1865 if (REAL_VALUE_ISNAN (d1))
1867 else if (REAL_VALUE_ISNAN (d2))
1870 inexact = real_arithmetic (&value, code, &d1, &d2);
1871 real_convert (&result, mode, &value);
1873 /* Don't constant fold this floating point operation if
1874 the result has overflowed and flag_trapping_math. */
1875 if (flag_trapping_math
1876 && MODE_HAS_INFINITIES (mode)
1877 && REAL_VALUE_ISINF (result)
1878 && !REAL_VALUE_ISINF (d1)
1879 && !REAL_VALUE_ISINF (d2))
1882 /* Don't constant fold this floating point operation if the
1883 result may dependent upon the run-time rounding mode and
1884 flag_rounding_math is set, or if GCC's software emulation
1885 is unable to accurately represent the result. */
1886 if ((flag_rounding_math
1887 || (REAL_MODE_FORMAT_COMPOSITE_P (mode)
1888 && !flag_unsafe_math_optimizations))
1889 && (inexact || !real_identical (&result, &value)))
1892 t = build_real (type, result);
1894 TREE_OVERFLOW (t) = TREE_OVERFLOW (arg1) | TREE_OVERFLOW (arg2);
1898 if (TREE_CODE (arg1) == FIXED_CST)
1900 FIXED_VALUE_TYPE f1;
1901 FIXED_VALUE_TYPE f2;
1902 FIXED_VALUE_TYPE result;
1907 /* The following codes are handled by fixed_arithmetic. */
1913 case TRUNC_DIV_EXPR:
1914 f2 = TREE_FIXED_CST (arg2);
1919 f2.data.high = TREE_INT_CST_HIGH (arg2);
1920 f2.data.low = TREE_INT_CST_LOW (arg2);
1928 f1 = TREE_FIXED_CST (arg1);
1929 type = TREE_TYPE (arg1);
1930 sat_p = TYPE_SATURATING (type);
1931 overflow_p = fixed_arithmetic (&result, code, &f1, &f2, sat_p);
1932 t = build_fixed (type, result);
1933 /* Propagate overflow flags. */
1934 if (overflow_p | TREE_OVERFLOW (arg1) | TREE_OVERFLOW (arg2))
1936 TREE_OVERFLOW (t) = 1;
1937 TREE_CONSTANT_OVERFLOW (t) = 1;
1939 else if (TREE_CONSTANT_OVERFLOW (arg1) | TREE_CONSTANT_OVERFLOW (arg2))
1940 TREE_CONSTANT_OVERFLOW (t) = 1;
1944 if (TREE_CODE (arg1) == COMPLEX_CST)
1946 tree type = TREE_TYPE (arg1);
1947 tree r1 = TREE_REALPART (arg1);
1948 tree i1 = TREE_IMAGPART (arg1);
1949 tree r2 = TREE_REALPART (arg2);
1950 tree i2 = TREE_IMAGPART (arg2);
1957 real = const_binop (code, r1, r2, notrunc);
1958 imag = const_binop (code, i1, i2, notrunc);
1962 real = const_binop (MINUS_EXPR,
1963 const_binop (MULT_EXPR, r1, r2, notrunc),
1964 const_binop (MULT_EXPR, i1, i2, notrunc),
1966 imag = const_binop (PLUS_EXPR,
1967 const_binop (MULT_EXPR, r1, i2, notrunc),
1968 const_binop (MULT_EXPR, i1, r2, notrunc),
1975 = const_binop (PLUS_EXPR,
1976 const_binop (MULT_EXPR, r2, r2, notrunc),
1977 const_binop (MULT_EXPR, i2, i2, notrunc),
1980 = const_binop (PLUS_EXPR,
1981 const_binop (MULT_EXPR, r1, r2, notrunc),
1982 const_binop (MULT_EXPR, i1, i2, notrunc),
1985 = const_binop (MINUS_EXPR,
1986 const_binop (MULT_EXPR, i1, r2, notrunc),
1987 const_binop (MULT_EXPR, r1, i2, notrunc),
1990 if (INTEGRAL_TYPE_P (TREE_TYPE (r1)))
1991 code = TRUNC_DIV_EXPR;
1993 real = const_binop (code, t1, magsquared, notrunc);
1994 imag = const_binop (code, t2, magsquared, notrunc);
2003 return build_complex (type, real, imag);
2009 /* Create a size type INT_CST node with NUMBER sign extended. KIND
2010 indicates which particular sizetype to create. */
2013 size_int_kind (HOST_WIDE_INT number, enum size_type_kind kind)
2015 return build_int_cst (sizetype_tab[(int) kind], number);
2018 /* Combine operands OP1 and OP2 with arithmetic operation CODE. CODE
2019 is a tree code. The type of the result is taken from the operands.
2020 Both must be equivalent integer types, ala int_binop_types_match_p.
2021 If the operands are constant, so is the result. */
2024 size_binop (enum tree_code code, tree arg0, tree arg1)
2026 tree type = TREE_TYPE (arg0);
2028 if (arg0 == error_mark_node || arg1 == error_mark_node)
2029 return error_mark_node;
2031 gcc_assert (int_binop_types_match_p (code, TREE_TYPE (arg0),
2034 /* Handle the special case of two integer constants faster. */
2035 if (TREE_CODE (arg0) == INTEGER_CST && TREE_CODE (arg1) == INTEGER_CST)
2037 /* And some specific cases even faster than that. */
2038 if (code == PLUS_EXPR)
2040 if (integer_zerop (arg0) && !TREE_OVERFLOW (arg0))
2042 if (integer_zerop (arg1) && !TREE_OVERFLOW (arg1))
2045 else if (code == MINUS_EXPR)
2047 if (integer_zerop (arg1) && !TREE_OVERFLOW (arg1))
2050 else if (code == MULT_EXPR)
2052 if (integer_onep (arg0) && !TREE_OVERFLOW (arg0))
2056 /* Handle general case of two integer constants. */
2057 return int_const_binop (code, arg0, arg1, 0);
2060 return fold_build2 (code, type, arg0, arg1);
2063 /* Given two values, either both of sizetype or both of bitsizetype,
2064 compute the difference between the two values. Return the value
2065 in signed type corresponding to the type of the operands. */
2068 size_diffop (tree arg0, tree arg1)
2070 tree type = TREE_TYPE (arg0);
2073 gcc_assert (int_binop_types_match_p (MINUS_EXPR, TREE_TYPE (arg0),
2076 /* If the type is already signed, just do the simple thing. */
2077 if (!TYPE_UNSIGNED (type))
2078 return size_binop (MINUS_EXPR, arg0, arg1);
2080 if (type == sizetype)
2082 else if (type == bitsizetype)
2083 ctype = sbitsizetype;
2085 ctype = signed_type_for (type);
2087 /* If either operand is not a constant, do the conversions to the signed
2088 type and subtract. The hardware will do the right thing with any
2089 overflow in the subtraction. */
2090 if (TREE_CODE (arg0) != INTEGER_CST || TREE_CODE (arg1) != INTEGER_CST)
2091 return size_binop (MINUS_EXPR, fold_convert (ctype, arg0),
2092 fold_convert (ctype, arg1));
2094 /* If ARG0 is larger than ARG1, subtract and return the result in CTYPE.
2095 Otherwise, subtract the other way, convert to CTYPE (we know that can't
2096 overflow) and negate (which can't either). Special-case a result
2097 of zero while we're here. */
2098 if (tree_int_cst_equal (arg0, arg1))
2099 return build_int_cst (ctype, 0);
2100 else if (tree_int_cst_lt (arg1, arg0))
2101 return fold_convert (ctype, size_binop (MINUS_EXPR, arg0, arg1));
2103 return size_binop (MINUS_EXPR, build_int_cst (ctype, 0),
2104 fold_convert (ctype, size_binop (MINUS_EXPR,
2108 /* A subroutine of fold_convert_const handling conversions of an
2109 INTEGER_CST to another integer type. */
2112 fold_convert_const_int_from_int (tree type, const_tree arg1)
2116 /* Given an integer constant, make new constant with new type,
2117 appropriately sign-extended or truncated. */
2118 t = force_fit_type_double (type, TREE_INT_CST_LOW (arg1),
2119 TREE_INT_CST_HIGH (arg1),
2120 /* Don't set the overflow when
2121 converting from a pointer, */
2122 !POINTER_TYPE_P (TREE_TYPE (arg1))
2123 /* or to a sizetype with same signedness
2124 and the precision is unchanged.
2125 ??? sizetype is always sign-extended,
2126 but its signedness depends on the
2127 frontend. Thus we see spurious overflows
2128 here if we do not check this. */
2129 && !((TYPE_PRECISION (TREE_TYPE (arg1))
2130 == TYPE_PRECISION (type))
2131 && (TYPE_UNSIGNED (TREE_TYPE (arg1))
2132 == TYPE_UNSIGNED (type))
2133 && ((TREE_CODE (TREE_TYPE (arg1)) == INTEGER_TYPE
2134 && TYPE_IS_SIZETYPE (TREE_TYPE (arg1)))
2135 || (TREE_CODE (type) == INTEGER_TYPE
2136 && TYPE_IS_SIZETYPE (type)))),
2137 (TREE_INT_CST_HIGH (arg1) < 0
2138 && (TYPE_UNSIGNED (type)
2139 < TYPE_UNSIGNED (TREE_TYPE (arg1))))
2140 | TREE_OVERFLOW (arg1));
2145 /* A subroutine of fold_convert_const handling conversions a REAL_CST
2146 to an integer type. */
2149 fold_convert_const_int_from_real (enum tree_code code, tree type, const_tree arg1)
2154 /* The following code implements the floating point to integer
2155 conversion rules required by the Java Language Specification,
2156 that IEEE NaNs are mapped to zero and values that overflow
2157 the target precision saturate, i.e. values greater than
2158 INT_MAX are mapped to INT_MAX, and values less than INT_MIN
2159 are mapped to INT_MIN. These semantics are allowed by the
2160 C and C++ standards that simply state that the behavior of
2161 FP-to-integer conversion is unspecified upon overflow. */
2163 HOST_WIDE_INT high, low;
2165 REAL_VALUE_TYPE x = TREE_REAL_CST (arg1);
2169 case FIX_TRUNC_EXPR:
2170 real_trunc (&r, VOIDmode, &x);
2177 /* If R is NaN, return zero and show we have an overflow. */
2178 if (REAL_VALUE_ISNAN (r))
2185 /* See if R is less than the lower bound or greater than the
2190 tree lt = TYPE_MIN_VALUE (type);
2191 REAL_VALUE_TYPE l = real_value_from_int_cst (NULL_TREE, lt);
2192 if (REAL_VALUES_LESS (r, l))
2195 high = TREE_INT_CST_HIGH (lt);
2196 low = TREE_INT_CST_LOW (lt);
2202 tree ut = TYPE_MAX_VALUE (type);
2205 REAL_VALUE_TYPE u = real_value_from_int_cst (NULL_TREE, ut);
2206 if (REAL_VALUES_LESS (u, r))
2209 high = TREE_INT_CST_HIGH (ut);
2210 low = TREE_INT_CST_LOW (ut);
2216 REAL_VALUE_TO_INT (&low, &high, r);
2218 t = force_fit_type_double (type, low, high, -1,
2219 overflow | TREE_OVERFLOW (arg1));
2223 /* A subroutine of fold_convert_const handling conversions of a
2224 FIXED_CST to an integer type. */
2227 fold_convert_const_int_from_fixed (tree type, const_tree arg1)
2230 double_int temp, temp_trunc;
2233 /* Right shift FIXED_CST to temp by fbit. */
2234 temp = TREE_FIXED_CST (arg1).data;
2235 mode = TREE_FIXED_CST (arg1).mode;
2236 if (GET_MODE_FBIT (mode) < 2 * HOST_BITS_PER_WIDE_INT)
2238 lshift_double (temp.low, temp.high,
2239 - GET_MODE_FBIT (mode), 2 * HOST_BITS_PER_WIDE_INT,
2240 &temp.low, &temp.high, SIGNED_FIXED_POINT_MODE_P (mode));
2242 /* Left shift temp to temp_trunc by fbit. */
2243 lshift_double (temp.low, temp.high,
2244 GET_MODE_FBIT (mode), 2 * HOST_BITS_PER_WIDE_INT,
2245 &temp_trunc.low, &temp_trunc.high,
2246 SIGNED_FIXED_POINT_MODE_P (mode));
2253 temp_trunc.high = 0;
2256 /* If FIXED_CST is negative, we need to round the value toward 0.
2257 By checking if the fractional bits are not zero to add 1 to temp. */
2258 if (SIGNED_FIXED_POINT_MODE_P (mode) && temp_trunc.high < 0
2259 && !double_int_equal_p (TREE_FIXED_CST (arg1).data, temp_trunc))
2264 temp = double_int_add (temp, one);
2267 /* Given a fixed-point constant, make new constant with new type,
2268 appropriately sign-extended or truncated. */
2269 t = force_fit_type_double (type, temp.low, temp.high, -1,
2271 && (TYPE_UNSIGNED (type)
2272 < TYPE_UNSIGNED (TREE_TYPE (arg1))))
2273 | TREE_OVERFLOW (arg1));
2278 /* A subroutine of fold_convert_const handling conversions a REAL_CST
2279 to another floating point type. */
2282 fold_convert_const_real_from_real (tree type, const_tree arg1)
2284 REAL_VALUE_TYPE value;
2287 real_convert (&value, TYPE_MODE (type), &TREE_REAL_CST (arg1));
2288 t = build_real (type, value);
2290 TREE_OVERFLOW (t) = TREE_OVERFLOW (arg1);
2294 /* A subroutine of fold_convert_const handling conversions a FIXED_CST
2295 to a floating point type. */
2298 fold_convert_const_real_from_fixed (tree type, const_tree arg1)
2300 REAL_VALUE_TYPE value;
2303 real_convert_from_fixed (&value, TYPE_MODE (type), &TREE_FIXED_CST (arg1));
2304 t = build_real (type, value);
2306 TREE_OVERFLOW (t) = TREE_OVERFLOW (arg1);
2307 TREE_CONSTANT_OVERFLOW (t)
2308 = TREE_OVERFLOW (t) | TREE_CONSTANT_OVERFLOW (arg1);
2312 /* A subroutine of fold_convert_const handling conversions a FIXED_CST
2313 to another fixed-point type. */
2316 fold_convert_const_fixed_from_fixed (tree type, const_tree arg1)
2318 FIXED_VALUE_TYPE value;
2322 overflow_p = fixed_convert (&value, TYPE_MODE (type), &TREE_FIXED_CST (arg1),
2323 TYPE_SATURATING (type));
2324 t = build_fixed (type, value);
2326 /* Propagate overflow flags. */
2327 if (overflow_p | TREE_OVERFLOW (arg1))
2329 TREE_OVERFLOW (t) = 1;
2330 TREE_CONSTANT_OVERFLOW (t) = 1;
2332 else if (TREE_CONSTANT_OVERFLOW (arg1))
2333 TREE_CONSTANT_OVERFLOW (t) = 1;
2337 /* A subroutine of fold_convert_const handling conversions an INTEGER_CST
2338 to a fixed-point type. */
2341 fold_convert_const_fixed_from_int (tree type, const_tree arg1)
2343 FIXED_VALUE_TYPE value;
2347 overflow_p = fixed_convert_from_int (&value, TYPE_MODE (type),
2348 TREE_INT_CST (arg1),
2349 TYPE_UNSIGNED (TREE_TYPE (arg1)),
2350 TYPE_SATURATING (type));
2351 t = build_fixed (type, value);
2353 /* Propagate overflow flags. */
2354 if (overflow_p | TREE_OVERFLOW (arg1))
2356 TREE_OVERFLOW (t) = 1;
2357 TREE_CONSTANT_OVERFLOW (t) = 1;
2359 else if (TREE_CONSTANT_OVERFLOW (arg1))
2360 TREE_CONSTANT_OVERFLOW (t) = 1;
2364 /* A subroutine of fold_convert_const handling conversions a REAL_CST
2365 to a fixed-point type. */
2368 fold_convert_const_fixed_from_real (tree type, const_tree arg1)
2370 FIXED_VALUE_TYPE value;
2374 overflow_p = fixed_convert_from_real (&value, TYPE_MODE (type),
2375 &TREE_REAL_CST (arg1),
2376 TYPE_SATURATING (type));
2377 t = build_fixed (type, value);
2379 /* Propagate overflow flags. */
2380 if (overflow_p | TREE_OVERFLOW (arg1))
2382 TREE_OVERFLOW (t) = 1;
2383 TREE_CONSTANT_OVERFLOW (t) = 1;
2385 else if (TREE_CONSTANT_OVERFLOW (arg1))
2386 TREE_CONSTANT_OVERFLOW (t) = 1;
2390 /* Attempt to fold type conversion operation CODE of expression ARG1 to
2391 type TYPE. If no simplification can be done return NULL_TREE. */
2394 fold_convert_const (enum tree_code code, tree type, tree arg1)
2396 if (TREE_TYPE (arg1) == type)
2399 if (POINTER_TYPE_P (type) || INTEGRAL_TYPE_P (type))
2401 if (TREE_CODE (arg1) == INTEGER_CST)
2402 return fold_convert_const_int_from_int (type, arg1);
2403 else if (TREE_CODE (arg1) == REAL_CST)
2404 return fold_convert_const_int_from_real (code, type, arg1);
2405 else if (TREE_CODE (arg1) == FIXED_CST)
2406 return fold_convert_const_int_from_fixed (type, arg1);
2408 else if (TREE_CODE (type) == REAL_TYPE)
2410 if (TREE_CODE (arg1) == INTEGER_CST)
2411 return build_real_from_int_cst (type, arg1);
2412 else if (TREE_CODE (arg1) == REAL_CST)
2413 return fold_convert_const_real_from_real (type, arg1);
2414 else if (TREE_CODE (arg1) == FIXED_CST)
2415 return fold_convert_const_real_from_fixed (type, arg1);
2417 else if (TREE_CODE (type) == FIXED_POINT_TYPE)
2419 if (TREE_CODE (arg1) == FIXED_CST)
2420 return fold_convert_const_fixed_from_fixed (type, arg1);
2421 else if (TREE_CODE (arg1) == INTEGER_CST)
2422 return fold_convert_const_fixed_from_int (type, arg1);
2423 else if (TREE_CODE (arg1) == REAL_CST)
2424 return fold_convert_const_fixed_from_real (type, arg1);
2429 /* Construct a vector of zero elements of vector type TYPE. */
2432 build_zero_vector (tree type)
2437 elem = fold_convert_const (NOP_EXPR, TREE_TYPE (type), integer_zero_node);
2438 units = TYPE_VECTOR_SUBPARTS (type);
2441 for (i = 0; i < units; i++)
2442 list = tree_cons (NULL_TREE, elem, list);
2443 return build_vector (type, list);
2446 /* Returns true, if ARG is convertible to TYPE using a NOP_EXPR. */
2449 fold_convertible_p (const_tree type, const_tree arg)
2451 tree orig = TREE_TYPE (arg);
2456 if (TREE_CODE (arg) == ERROR_MARK
2457 || TREE_CODE (type) == ERROR_MARK
2458 || TREE_CODE (orig) == ERROR_MARK)
2461 if (TYPE_MAIN_VARIANT (type) == TYPE_MAIN_VARIANT (orig))
2464 switch (TREE_CODE (type))
2466 case INTEGER_TYPE: case ENUMERAL_TYPE: case BOOLEAN_TYPE:
2467 case POINTER_TYPE: case REFERENCE_TYPE:
2469 if (INTEGRAL_TYPE_P (orig) || POINTER_TYPE_P (orig)
2470 || TREE_CODE (orig) == OFFSET_TYPE)
2472 return (TREE_CODE (orig) == VECTOR_TYPE
2473 && tree_int_cst_equal (TYPE_SIZE (type), TYPE_SIZE (orig)));
2476 case FIXED_POINT_TYPE:
2480 return TREE_CODE (type) == TREE_CODE (orig);
2487 /* Convert expression ARG to type TYPE. Used by the middle-end for
2488 simple conversions in preference to calling the front-end's convert. */
2491 fold_convert (tree type, tree arg)
2493 tree orig = TREE_TYPE (arg);
2499 if (TREE_CODE (arg) == ERROR_MARK
2500 || TREE_CODE (type) == ERROR_MARK
2501 || TREE_CODE (orig) == ERROR_MARK)
2502 return error_mark_node;
2504 if (TYPE_MAIN_VARIANT (type) == TYPE_MAIN_VARIANT (orig))
2505 return fold_build1 (NOP_EXPR, type, arg);
2507 switch (TREE_CODE (type))
2509 case INTEGER_TYPE: case ENUMERAL_TYPE: case BOOLEAN_TYPE:
2510 case POINTER_TYPE: case REFERENCE_TYPE:
2512 if (TREE_CODE (arg) == INTEGER_CST)
2514 tem = fold_convert_const (NOP_EXPR, type, arg);
2515 if (tem != NULL_TREE)
2518 if (INTEGRAL_TYPE_P (orig) || POINTER_TYPE_P (orig)
2519 || TREE_CODE (orig) == OFFSET_TYPE)
2520 return fold_build1 (NOP_EXPR, type, arg);
2521 if (TREE_CODE (orig) == COMPLEX_TYPE)
2523 tem = fold_build1 (REALPART_EXPR, TREE_TYPE (orig), arg);
2524 return fold_convert (type, tem);
2526 gcc_assert (TREE_CODE (orig) == VECTOR_TYPE
2527 && tree_int_cst_equal (TYPE_SIZE (type), TYPE_SIZE (orig)));
2528 return fold_build1 (NOP_EXPR, type, arg);
2531 if (TREE_CODE (arg) == INTEGER_CST)
2533 tem = fold_convert_const (FLOAT_EXPR, type, arg);
2534 if (tem != NULL_TREE)
2537 else if (TREE_CODE (arg) == REAL_CST)
2539 tem = fold_convert_const (NOP_EXPR, type, arg);
2540 if (tem != NULL_TREE)
2543 else if (TREE_CODE (arg) == FIXED_CST)
2545 tem = fold_convert_const (FIXED_CONVERT_EXPR, type, arg);
2546 if (tem != NULL_TREE)
2550 switch (TREE_CODE (orig))
2553 case BOOLEAN_TYPE: case ENUMERAL_TYPE:
2554 case POINTER_TYPE: case REFERENCE_TYPE:
2555 return fold_build1 (FLOAT_EXPR, type, arg);
2558 return fold_build1 (NOP_EXPR, type, arg);
2560 case FIXED_POINT_TYPE:
2561 return fold_build1 (FIXED_CONVERT_EXPR, type, arg);
2564 tem = fold_build1 (REALPART_EXPR, TREE_TYPE (orig), arg);
2565 return fold_convert (type, tem);
2571 case FIXED_POINT_TYPE:
2572 if (TREE_CODE (arg) == FIXED_CST || TREE_CODE (arg) == INTEGER_CST
2573 || TREE_CODE (arg) == REAL_CST)
2575 tem = fold_convert_const (FIXED_CONVERT_EXPR, type, arg);
2576 if (tem != NULL_TREE)
2580 switch (TREE_CODE (orig))
2582 case FIXED_POINT_TYPE:
2587 return fold_build1 (FIXED_CONVERT_EXPR, type, arg);
2590 tem = fold_build1 (REALPART_EXPR, TREE_TYPE (orig), arg);
2591 return fold_convert (type, tem);
2598 switch (TREE_CODE (orig))
2601 case BOOLEAN_TYPE: case ENUMERAL_TYPE:
2602 case POINTER_TYPE: case REFERENCE_TYPE:
2604 case FIXED_POINT_TYPE:
2605 return build2 (COMPLEX_EXPR, type,
2606 fold_convert (TREE_TYPE (type), arg),
2607 fold_convert (TREE_TYPE (type), integer_zero_node));
2612 if (TREE_CODE (arg) == COMPLEX_EXPR)
2614 rpart = fold_convert (TREE_TYPE (type), TREE_OPERAND (arg, 0));
2615 ipart = fold_convert (TREE_TYPE (type), TREE_OPERAND (arg, 1));
2616 return fold_build2 (COMPLEX_EXPR, type, rpart, ipart);
2619 arg = save_expr (arg);
2620 rpart = fold_build1 (REALPART_EXPR, TREE_TYPE (orig), arg);
2621 ipart = fold_build1 (IMAGPART_EXPR, TREE_TYPE (orig), arg);
2622 rpart = fold_convert (TREE_TYPE (type), rpart);
2623 ipart = fold_convert (TREE_TYPE (type), ipart);
2624 return fold_build2 (COMPLEX_EXPR, type, rpart, ipart);
2632 if (integer_zerop (arg))
2633 return build_zero_vector (type);
2634 gcc_assert (tree_int_cst_equal (TYPE_SIZE (type), TYPE_SIZE (orig)));
2635 gcc_assert (INTEGRAL_TYPE_P (orig) || POINTER_TYPE_P (orig)
2636 || TREE_CODE (orig) == VECTOR_TYPE);
2637 return fold_build1 (VIEW_CONVERT_EXPR, type, arg);
2640 tem = fold_ignored_result (arg);
2641 if (TREE_CODE (tem) == GIMPLE_MODIFY_STMT)
2643 return fold_build1 (NOP_EXPR, type, tem);
2650 /* Return false if expr can be assumed not to be an lvalue, true
2654 maybe_lvalue_p (const_tree x)
2656 /* We only need to wrap lvalue tree codes. */
2657 switch (TREE_CODE (x))
2668 case ALIGN_INDIRECT_REF:
2669 case MISALIGNED_INDIRECT_REF:
2671 case ARRAY_RANGE_REF:
2677 case PREINCREMENT_EXPR:
2678 case PREDECREMENT_EXPR:
2680 case TRY_CATCH_EXPR:
2681 case WITH_CLEANUP_EXPR:
2684 case GIMPLE_MODIFY_STMT:
2693 /* Assume the worst for front-end tree codes. */
2694 if ((int)TREE_CODE (x) >= NUM_TREE_CODES)
2702 /* Return an expr equal to X but certainly not valid as an lvalue. */
2707 /* While we are in GIMPLE, NON_LVALUE_EXPR doesn't mean anything to
2712 if (! maybe_lvalue_p (x))
2714 return build1 (NON_LVALUE_EXPR, TREE_TYPE (x), x);
2717 /* Nonzero means lvalues are limited to those valid in pedantic ANSI C.
2718 Zero means allow extended lvalues. */
2720 int pedantic_lvalues;
2722 /* When pedantic, return an expr equal to X but certainly not valid as a
2723 pedantic lvalue. Otherwise, return X. */
2726 pedantic_non_lvalue (tree x)
2728 if (pedantic_lvalues)
2729 return non_lvalue (x);
2734 /* Given a tree comparison code, return the code that is the logical inverse
2735 of the given code. It is not safe to do this for floating-point
2736 comparisons, except for NE_EXPR and EQ_EXPR, so we receive a machine mode
2737 as well: if reversing the comparison is unsafe, return ERROR_MARK. */
2740 invert_tree_comparison (enum tree_code code, bool honor_nans)
2742 if (honor_nans && flag_trapping_math)
2752 return honor_nans ? UNLE_EXPR : LE_EXPR;
2754 return honor_nans ? UNLT_EXPR : LT_EXPR;
2756 return honor_nans ? UNGE_EXPR : GE_EXPR;
2758 return honor_nans ? UNGT_EXPR : GT_EXPR;
2772 return UNORDERED_EXPR;
2773 case UNORDERED_EXPR:
2774 return ORDERED_EXPR;
2780 /* Similar, but return the comparison that results if the operands are
2781 swapped. This is safe for floating-point. */
2784 swap_tree_comparison (enum tree_code code)
2791 case UNORDERED_EXPR:
2817 /* Convert a comparison tree code from an enum tree_code representation
2818 into a compcode bit-based encoding. This function is the inverse of
2819 compcode_to_comparison. */
2821 static enum comparison_code
2822 comparison_to_compcode (enum tree_code code)
2839 return COMPCODE_ORD;
2840 case UNORDERED_EXPR:
2841 return COMPCODE_UNORD;
2843 return COMPCODE_UNLT;
2845 return COMPCODE_UNEQ;
2847 return COMPCODE_UNLE;
2849 return COMPCODE_UNGT;
2851 return COMPCODE_LTGT;
2853 return COMPCODE_UNGE;
2859 /* Convert a compcode bit-based encoding of a comparison operator back
2860 to GCC's enum tree_code representation. This function is the
2861 inverse of comparison_to_compcode. */
2863 static enum tree_code
2864 compcode_to_comparison (enum comparison_code code)
2881 return ORDERED_EXPR;
2882 case COMPCODE_UNORD:
2883 return UNORDERED_EXPR;
2901 /* Return a tree for the comparison which is the combination of
2902 doing the AND or OR (depending on CODE) of the two operations LCODE
2903 and RCODE on the identical operands LL_ARG and LR_ARG. Take into account
2904 the possibility of trapping if the mode has NaNs, and return NULL_TREE
2905 if this makes the transformation invalid. */
2908 combine_comparisons (enum tree_code code, enum tree_code lcode,
2909 enum tree_code rcode, tree truth_type,
2910 tree ll_arg, tree lr_arg)
2912 bool honor_nans = HONOR_NANS (TYPE_MODE (TREE_TYPE (ll_arg)));
2913 enum comparison_code lcompcode = comparison_to_compcode (lcode);
2914 enum comparison_code rcompcode = comparison_to_compcode (rcode);
2915 enum comparison_code compcode;
2919 case TRUTH_AND_EXPR: case TRUTH_ANDIF_EXPR:
2920 compcode = lcompcode & rcompcode;
2923 case TRUTH_OR_EXPR: case TRUTH_ORIF_EXPR:
2924 compcode = lcompcode | rcompcode;
2933 /* Eliminate unordered comparisons, as well as LTGT and ORD
2934 which are not used unless the mode has NaNs. */
2935 compcode &= ~COMPCODE_UNORD;
2936 if (compcode == COMPCODE_LTGT)
2937 compcode = COMPCODE_NE;
2938 else if (compcode == COMPCODE_ORD)
2939 compcode = COMPCODE_TRUE;
2941 else if (flag_trapping_math)
2943 /* Check that the original operation and the optimized ones will trap
2944 under the same condition. */
2945 bool ltrap = (lcompcode & COMPCODE_UNORD) == 0
2946 && (lcompcode != COMPCODE_EQ)
2947 && (lcompcode != COMPCODE_ORD);
2948 bool rtrap = (rcompcode & COMPCODE_UNORD) == 0
2949 && (rcompcode != COMPCODE_EQ)
2950 && (rcompcode != COMPCODE_ORD);
2951 bool trap = (compcode & COMPCODE_UNORD) == 0
2952 && (compcode != COMPCODE_EQ)
2953 && (compcode != COMPCODE_ORD);
2955 /* In a short-circuited boolean expression the LHS might be
2956 such that the RHS, if evaluated, will never trap. For
2957 example, in ORD (x, y) && (x < y), we evaluate the RHS only
2958 if neither x nor y is NaN. (This is a mixed blessing: for
2959 example, the expression above will never trap, hence
2960 optimizing it to x < y would be invalid). */
2961 if ((code == TRUTH_ORIF_EXPR && (lcompcode & COMPCODE_UNORD))
2962 || (code == TRUTH_ANDIF_EXPR && !(lcompcode & COMPCODE_UNORD)))
2965 /* If the comparison was short-circuited, and only the RHS
2966 trapped, we may now generate a spurious trap. */
2968 && (code == TRUTH_ANDIF_EXPR || code == TRUTH_ORIF_EXPR))
2971 /* If we changed the conditions that cause a trap, we lose. */
2972 if ((ltrap || rtrap) != trap)
2976 if (compcode == COMPCODE_TRUE)
2977 return constant_boolean_node (true, truth_type);
2978 else if (compcode == COMPCODE_FALSE)
2979 return constant_boolean_node (false, truth_type);
2981 return fold_build2 (compcode_to_comparison (compcode),
2982 truth_type, ll_arg, lr_arg);
2985 /* Return nonzero if CODE is a tree code that represents a truth value. */
2988 truth_value_p (enum tree_code code)
2990 return (TREE_CODE_CLASS (code) == tcc_comparison
2991 || code == TRUTH_AND_EXPR || code == TRUTH_ANDIF_EXPR
2992 || code == TRUTH_OR_EXPR || code == TRUTH_ORIF_EXPR
2993 || code == TRUTH_XOR_EXPR || code == TRUTH_NOT_EXPR);
2996 /* Return nonzero if two operands (typically of the same tree node)
2997 are necessarily equal. If either argument has side-effects this
2998 function returns zero. FLAGS modifies behavior as follows:
3000 If OEP_ONLY_CONST is set, only return nonzero for constants.
3001 This function tests whether the operands are indistinguishable;
3002 it does not test whether they are equal using C's == operation.
3003 The distinction is important for IEEE floating point, because
3004 (1) -0.0 and 0.0 are distinguishable, but -0.0==0.0, and
3005 (2) two NaNs may be indistinguishable, but NaN!=NaN.
3007 If OEP_ONLY_CONST is unset, a VAR_DECL is considered equal to itself
3008 even though it may hold multiple values during a function.
3009 This is because a GCC tree node guarantees that nothing else is
3010 executed between the evaluation of its "operands" (which may often
3011 be evaluated in arbitrary order). Hence if the operands themselves
3012 don't side-effect, the VAR_DECLs, PARM_DECLs etc... must hold the
3013 same value in each operand/subexpression. Hence leaving OEP_ONLY_CONST
3014 unset means assuming isochronic (or instantaneous) tree equivalence.
3015 Unless comparing arbitrary expression trees, such as from different
3016 statements, this flag can usually be left unset.
3018 If OEP_PURE_SAME is set, then pure functions with identical arguments
3019 are considered the same. It is used when the caller has other ways
3020 to ensure that global memory is unchanged in between. */
3023 operand_equal_p (const_tree arg0, const_tree arg1, unsigned int flags)
3025 /* If either is ERROR_MARK, they aren't equal. */
3026 if (TREE_CODE (arg0) == ERROR_MARK || TREE_CODE (arg1) == ERROR_MARK)
3029 /* Check equality of integer constants before bailing out due to
3030 precision differences. */
3031 if (TREE_CODE (arg0) == INTEGER_CST && TREE_CODE (arg1) == INTEGER_CST)
3032 return tree_int_cst_equal (arg0, arg1);
3034 /* If both types don't have the same signedness, then we can't consider
3035 them equal. We must check this before the STRIP_NOPS calls
3036 because they may change the signedness of the arguments. */
3037 if (TYPE_UNSIGNED (TREE_TYPE (arg0)) != TYPE_UNSIGNED (TREE_TYPE (arg1)))
3040 /* If both types don't have the same precision, then it is not safe
3042 if (TYPE_PRECISION (TREE_TYPE (arg0)) != TYPE_PRECISION (TREE_TYPE (arg1)))
3048 /* In case both args are comparisons but with different comparison
3049 code, try to swap the comparison operands of one arg to produce
3050 a match and compare that variant. */
3051 if (TREE_CODE (arg0) != TREE_CODE (arg1)
3052 && COMPARISON_CLASS_P (arg0)
3053 && COMPARISON_CLASS_P (arg1))
3055 enum tree_code swap_code = swap_tree_comparison (TREE_CODE (arg1));
3057 if (TREE_CODE (arg0) == swap_code)
3058 return operand_equal_p (TREE_OPERAND (arg0, 0),
3059 TREE_OPERAND (arg1, 1), flags)
3060 && operand_equal_p (TREE_OPERAND (arg0, 1),
3061 TREE_OPERAND (arg1, 0), flags);
3064 if (TREE_CODE (arg0) != TREE_CODE (arg1)
3065 /* This is needed for conversions and for COMPONENT_REF.
3066 Might as well play it safe and always test this. */
3067 || TREE_CODE (TREE_TYPE (arg0)) == ERROR_MARK
3068 || TREE_CODE (TREE_TYPE (arg1)) == ERROR_MARK
3069 || TYPE_MODE (TREE_TYPE (arg0)) != TYPE_MODE (TREE_TYPE (arg1)))
3072 /* If ARG0 and ARG1 are the same SAVE_EXPR, they are necessarily equal.
3073 We don't care about side effects in that case because the SAVE_EXPR
3074 takes care of that for us. In all other cases, two expressions are
3075 equal if they have no side effects. If we have two identical
3076 expressions with side effects that should be treated the same due
3077 to the only side effects being identical SAVE_EXPR's, that will
3078 be detected in the recursive calls below. */
3079 if (arg0 == arg1 && ! (flags & OEP_ONLY_CONST)
3080 && (TREE_CODE (arg0) == SAVE_EXPR
3081 || (! TREE_SIDE_EFFECTS (arg0) && ! TREE_SIDE_EFFECTS (arg1))))
3084 /* Next handle constant cases, those for which we can return 1 even
3085 if ONLY_CONST is set. */
3086 if (TREE_CONSTANT (arg0) && TREE_CONSTANT (arg1))
3087 switch (TREE_CODE (arg0))
3090 return tree_int_cst_equal (arg0, arg1);
3093 return FIXED_VALUES_IDENTICAL (TREE_FIXED_CST (arg0),
3094 TREE_FIXED_CST (arg1));
3097 if (REAL_VALUES_IDENTICAL (TREE_REAL_CST (arg0),
3098 TREE_REAL_CST (arg1)))
3102 if (!HONOR_SIGNED_ZEROS (TYPE_MODE (TREE_TYPE (arg0))))
3104 /* If we do not distinguish between signed and unsigned zero,
3105 consider them equal. */
3106 if (real_zerop (arg0) && real_zerop (arg1))
3115 v1 = TREE_VECTOR_CST_ELTS (arg0);
3116 v2 = TREE_VECTOR_CST_ELTS (arg1);
3119 if (!operand_equal_p (TREE_VALUE (v1), TREE_VALUE (v2),
3122 v1 = TREE_CHAIN (v1);
3123 v2 = TREE_CHAIN (v2);
3130 return (operand_equal_p (TREE_REALPART (arg0), TREE_REALPART (arg1),
3132 && operand_equal_p (TREE_IMAGPART (arg0), TREE_IMAGPART (arg1),
3136 return (TREE_STRING_LENGTH (arg0) == TREE_STRING_LENGTH (arg1)
3137 && ! memcmp (TREE_STRING_POINTER (arg0),
3138 TREE_STRING_POINTER (arg1),
3139 TREE_STRING_LENGTH (arg0)));
3142 return operand_equal_p (TREE_OPERAND (arg0, 0), TREE_OPERAND (arg1, 0),
3148 if (flags & OEP_ONLY_CONST)
3151 /* Define macros to test an operand from arg0 and arg1 for equality and a
3152 variant that allows null and views null as being different from any
3153 non-null value. In the latter case, if either is null, the both
3154 must be; otherwise, do the normal comparison. */
3155 #define OP_SAME(N) operand_equal_p (TREE_OPERAND (arg0, N), \
3156 TREE_OPERAND (arg1, N), flags)
3158 #define OP_SAME_WITH_NULL(N) \
3159 ((!TREE_OPERAND (arg0, N) || !TREE_OPERAND (arg1, N)) \
3160 ? TREE_OPERAND (arg0, N) == TREE_OPERAND (arg1, N) : OP_SAME (N))
3162 switch (TREE_CODE_CLASS (TREE_CODE (arg0)))
3165 /* Two conversions are equal only if signedness and modes match. */
3166 switch (TREE_CODE (arg0))
3170 case FIX_TRUNC_EXPR:
3171 if (TYPE_UNSIGNED (TREE_TYPE (arg0))
3172 != TYPE_UNSIGNED (TREE_TYPE (arg1)))
3182 case tcc_comparison:
3184 if (OP_SAME (0) && OP_SAME (1))
3187 /* For commutative ops, allow the other order. */
3188 return (commutative_tree_code (TREE_CODE (arg0))
3189 && operand_equal_p (TREE_OPERAND (arg0, 0),
3190 TREE_OPERAND (arg1, 1), flags)
3191 && operand_equal_p (TREE_OPERAND (arg0, 1),
3192 TREE_OPERAND (arg1, 0), flags));
3195 /* If either of the pointer (or reference) expressions we are
3196 dereferencing contain a side effect, these cannot be equal. */
3197 if (TREE_SIDE_EFFECTS (arg0)
3198 || TREE_SIDE_EFFECTS (arg1))
3201 switch (TREE_CODE (arg0))
3204 case ALIGN_INDIRECT_REF:
3205 case MISALIGNED_INDIRECT_REF:
3211 case ARRAY_RANGE_REF:
3212 /* Operands 2 and 3 may be null.
3213 Compare the array index by value if it is constant first as we
3214 may have different types but same value here. */
3216 && (tree_int_cst_equal (TREE_OPERAND (arg0, 1),
3217 TREE_OPERAND (arg1, 1))
3219 && OP_SAME_WITH_NULL (2)
3220 && OP_SAME_WITH_NULL (3));
3223 /* Handle operand 2 the same as for ARRAY_REF. Operand 0
3224 may be NULL when we're called to compare MEM_EXPRs. */
3225 return OP_SAME_WITH_NULL (0)
3227 && OP_SAME_WITH_NULL (2);
3230 return OP_SAME (0) && OP_SAME (1) && OP_SAME (2);
3236 case tcc_expression:
3237 switch (TREE_CODE (arg0))
3240 case TRUTH_NOT_EXPR:
3243 case TRUTH_ANDIF_EXPR:
3244 case TRUTH_ORIF_EXPR:
3245 return OP_SAME (0) && OP_SAME (1);
3247 case TRUTH_AND_EXPR:
3249 case TRUTH_XOR_EXPR:
3250 if (OP_SAME (0) && OP_SAME (1))
3253 /* Otherwise take into account this is a commutative operation. */
3254 return (operand_equal_p (TREE_OPERAND (arg0, 0),
3255 TREE_OPERAND (arg1, 1), flags)
3256 && operand_equal_p (TREE_OPERAND (arg0, 1),
3257 TREE_OPERAND (arg1, 0), flags));
3264 switch (TREE_CODE (arg0))
3267 /* If the CALL_EXPRs call different functions, then they
3268 clearly can not be equal. */
3269 if (! operand_equal_p (CALL_EXPR_FN (arg0), CALL_EXPR_FN (arg1),
3274 unsigned int cef = call_expr_flags (arg0);
3275 if (flags & OEP_PURE_SAME)
3276 cef &= ECF_CONST | ECF_PURE;
3283 /* Now see if all the arguments are the same. */
3285 const_call_expr_arg_iterator iter0, iter1;
3287 for (a0 = first_const_call_expr_arg (arg0, &iter0),
3288 a1 = first_const_call_expr_arg (arg1, &iter1);
3290 a0 = next_const_call_expr_arg (&iter0),
3291 a1 = next_const_call_expr_arg (&iter1))
3292 if (! operand_equal_p (a0, a1, flags))
3295 /* If we get here and both argument lists are exhausted
3296 then the CALL_EXPRs are equal. */
3297 return ! (a0 || a1);
3303 case tcc_declaration:
3304 /* Consider __builtin_sqrt equal to sqrt. */
3305 return (TREE_CODE (arg0) == FUNCTION_DECL
3306 && DECL_BUILT_IN (arg0) && DECL_BUILT_IN (arg1)
3307 && DECL_BUILT_IN_CLASS (arg0) == DECL_BUILT_IN_CLASS (arg1)
3308 && DECL_FUNCTION_CODE (arg0) == DECL_FUNCTION_CODE (arg1));
3315 #undef OP_SAME_WITH_NULL
3318 /* Similar to operand_equal_p, but see if ARG0 might have been made by
3319 shorten_compare from ARG1 when ARG1 was being compared with OTHER.
3321 When in doubt, return 0. */
3324 operand_equal_for_comparison_p (tree arg0, tree arg1, tree other)
3326 int unsignedp1, unsignedpo;
3327 tree primarg0, primarg1, primother;
3328 unsigned int correct_width;
3330 if (operand_equal_p (arg0, arg1, 0))
3333 if (! INTEGRAL_TYPE_P (TREE_TYPE (arg0))
3334 || ! INTEGRAL_TYPE_P (TREE_TYPE (arg1)))
3337 /* Discard any conversions that don't change the modes of ARG0 and ARG1
3338 and see if the inner values are the same. This removes any
3339 signedness comparison, which doesn't matter here. */
3340 primarg0 = arg0, primarg1 = arg1;
3341 STRIP_NOPS (primarg0);
3342 STRIP_NOPS (primarg1);
3343 if (operand_equal_p (primarg0, primarg1, 0))
3346 /* Duplicate what shorten_compare does to ARG1 and see if that gives the
3347 actual comparison operand, ARG0.
3349 First throw away any conversions to wider types
3350 already present in the operands. */
3352 primarg1 = get_narrower (arg1, &unsignedp1);
3353 primother = get_narrower (other, &unsignedpo);
3355 correct_width = TYPE_PRECISION (TREE_TYPE (arg1));
3356 if (unsignedp1 == unsignedpo
3357 && TYPE_PRECISION (TREE_TYPE (primarg1)) < correct_width
3358 && TYPE_PRECISION (TREE_TYPE (primother)) < correct_width)
3360 tree type = TREE_TYPE (arg0);
3362 /* Make sure shorter operand is extended the right way
3363 to match the longer operand. */
3364 primarg1 = fold_convert (signed_or_unsigned_type_for
3365 (unsignedp1, TREE_TYPE (primarg1)), primarg1);
3367 if (operand_equal_p (arg0, fold_convert (type, primarg1), 0))
3374 /* See if ARG is an expression that is either a comparison or is performing
3375 arithmetic on comparisons. The comparisons must only be comparing
3376 two different values, which will be stored in *CVAL1 and *CVAL2; if
3377 they are nonzero it means that some operands have already been found.
3378 No variables may be used anywhere else in the expression except in the
3379 comparisons. If SAVE_P is true it means we removed a SAVE_EXPR around
3380 the expression and save_expr needs to be called with CVAL1 and CVAL2.
3382 If this is true, return 1. Otherwise, return zero. */
3385 twoval_comparison_p (tree arg, tree *cval1, tree *cval2, int *save_p)
3387 enum tree_code code = TREE_CODE (arg);
3388 enum tree_code_class class = TREE_CODE_CLASS (code);
3390 /* We can handle some of the tcc_expression cases here. */
3391 if (class == tcc_expression && code == TRUTH_NOT_EXPR)
3393 else if (class == tcc_expression
3394 && (code == TRUTH_ANDIF_EXPR || code == TRUTH_ORIF_EXPR
3395 || code == COMPOUND_EXPR))
3398 else if (class == tcc_expression && code == SAVE_EXPR
3399 && ! TREE_SIDE_EFFECTS (TREE_OPERAND (arg, 0)))
3401 /* If we've already found a CVAL1 or CVAL2, this expression is
3402 two complex to handle. */
3403 if (*cval1 || *cval2)
3413 return twoval_comparison_p (TREE_OPERAND (arg, 0), cval1, cval2, save_p);
3416 return (twoval_comparison_p (TREE_OPERAND (arg, 0), cval1, cval2, save_p)
3417 && twoval_comparison_p (TREE_OPERAND (arg, 1),
3418 cval1, cval2, save_p));
3423 case tcc_expression:
3424 if (code == COND_EXPR)
3425 return (twoval_comparison_p (TREE_OPERAND (arg, 0),
3426 cval1, cval2, save_p)
3427 && twoval_comparison_p (TREE_OPERAND (arg, 1),
3428 cval1, cval2, save_p)
3429 && twoval_comparison_p (TREE_OPERAND (arg, 2),
3430 cval1, cval2, save_p));
3433 case tcc_comparison:
3434 /* First see if we can handle the first operand, then the second. For
3435 the second operand, we know *CVAL1 can't be zero. It must be that
3436 one side of the comparison is each of the values; test for the
3437 case where this isn't true by failing if the two operands
3440 if (operand_equal_p (TREE_OPERAND (arg, 0),
3441 TREE_OPERAND (arg, 1), 0))
3445 *cval1 = TREE_OPERAND (arg, 0);
3446 else if (operand_equal_p (*cval1, TREE_OPERAND (arg, 0), 0))
3448 else if (*cval2 == 0)
3449 *cval2 = TREE_OPERAND (arg, 0);
3450 else if (operand_equal_p (*cval2, TREE_OPERAND (arg, 0), 0))
3455 if (operand_equal_p (*cval1, TREE_OPERAND (arg, 1), 0))
3457 else if (*cval2 == 0)
3458 *cval2 = TREE_OPERAND (arg, 1);
3459 else if (operand_equal_p (*cval2, TREE_OPERAND (arg, 1), 0))
3471 /* ARG is a tree that is known to contain just arithmetic operations and
3472 comparisons. Evaluate the operations in the tree substituting NEW0 for
3473 any occurrence of OLD0 as an operand of a comparison and likewise for
3477 eval_subst (tree arg, tree old0, tree new0, tree old1, tree new1)
3479 tree type = TREE_TYPE (arg);
3480 enum tree_code code = TREE_CODE (arg);
3481 enum tree_code_class class = TREE_CODE_CLASS (code);
3483 /* We can handle some of the tcc_expression cases here. */
3484 if (class == tcc_expression && code == TRUTH_NOT_EXPR)
3486 else if (class == tcc_expression
3487 && (code == TRUTH_ANDIF_EXPR || code == TRUTH_ORIF_EXPR))
3493 return fold_build1 (code, type,
3494 eval_subst (TREE_OPERAND (arg, 0),
3495 old0, new0, old1, new1));
3498 return fold_build2 (code, type,
3499 eval_subst (TREE_OPERAND (arg, 0),
3500 old0, new0, old1, new1),
3501 eval_subst (TREE_OPERAND (arg, 1),
3502 old0, new0, old1, new1));
3504 case tcc_expression:
3508 return eval_subst (TREE_OPERAND (arg, 0), old0, new0, old1, new1);
3511 return eval_subst (TREE_OPERAND (arg, 1), old0, new0, old1, new1);
3514 return fold_build3 (code, type,
3515 eval_subst (TREE_OPERAND (arg, 0),
3516 old0, new0, old1, new1),
3517 eval_subst (TREE_OPERAND (arg, 1),
3518 old0, new0, old1, new1),
3519 eval_subst (TREE_OPERAND (arg, 2),
3520 old0, new0, old1, new1));
3524 /* Fall through - ??? */
3526 case tcc_comparison:
3528 tree arg0 = TREE_OPERAND (arg, 0);
3529 tree arg1 = TREE_OPERAND (arg, 1);
3531 /* We need to check both for exact equality and tree equality. The
3532 former will be true if the operand has a side-effect. In that
3533 case, we know the operand occurred exactly once. */
3535 if (arg0 == old0 || operand_equal_p (arg0, old0, 0))
3537 else if (arg0 == old1 || operand_equal_p (arg0, old1, 0))
3540 if (arg1 == old0 || operand_equal_p (arg1, old0, 0))
3542 else if (arg1 == old1 || operand_equal_p (arg1, old1, 0))
3545 return fold_build2 (code, type, arg0, arg1);
3553 /* Return a tree for the case when the result of an expression is RESULT
3554 converted to TYPE and OMITTED was previously an operand of the expression
3555 but is now not needed (e.g., we folded OMITTED * 0).
3557 If OMITTED has side effects, we must evaluate it. Otherwise, just do
3558 the conversion of RESULT to TYPE. */
3561 omit_one_operand (tree type, tree result, tree omitted)
3563 tree t = fold_convert (type, result);
3565 /* If the resulting operand is an empty statement, just return the omitted
3566 statement casted to void. */
3567 if (IS_EMPTY_STMT (t) && TREE_SIDE_EFFECTS (omitted))
3568 return build1 (NOP_EXPR, void_type_node, fold_ignored_result (omitted));
3570 if (TREE_SIDE_EFFECTS (omitted))
3571 return build2 (COMPOUND_EXPR, type, fold_ignored_result (omitted), t);
3573 return non_lvalue (t);
3576 /* Similar, but call pedantic_non_lvalue instead of non_lvalue. */
3579 pedantic_omit_one_operand (tree type, tree result, tree omitted)
3581 tree t = fold_convert (type, result);
3583 /* If the resulting operand is an empty statement, just return the omitted
3584 statement casted to void. */
3585 if (IS_EMPTY_STMT (t) && TREE_SIDE_EFFECTS (omitted))
3586 return build1 (NOP_EXPR, void_type_node, fold_ignored_result (omitted));
3588 if (TREE_SIDE_EFFECTS (omitted))
3589 return build2 (COMPOUND_EXPR, type, fold_ignored_result (omitted), t);
3591 return pedantic_non_lvalue (t);
3594 /* Return a tree for the case when the result of an expression is RESULT
3595 converted to TYPE and OMITTED1 and OMITTED2 were previously operands
3596 of the expression but are now not needed.
3598 If OMITTED1 or OMITTED2 has side effects, they must be evaluated.
3599 If both OMITTED1 and OMITTED2 have side effects, OMITTED1 is
3600 evaluated before OMITTED2. Otherwise, if neither has side effects,
3601 just do the conversion of RESULT to TYPE. */
3604 omit_two_operands (tree type, tree result, tree omitted1, tree omitted2)
3606 tree t = fold_convert (type, result);
3608 if (TREE_SIDE_EFFECTS (omitted2))
3609 t = build2 (COMPOUND_EXPR, type, omitted2, t);
3610 if (TREE_SIDE_EFFECTS (omitted1))
3611 t = build2 (COMPOUND_EXPR, type, omitted1, t);
3613 return TREE_CODE (t) != COMPOUND_EXPR ? non_lvalue (t) : t;
3617 /* Return a simplified tree node for the truth-negation of ARG. This
3618 never alters ARG itself. We assume that ARG is an operation that
3619 returns a truth value (0 or 1).
3621 FIXME: one would think we would fold the result, but it causes
3622 problems with the dominator optimizer. */
3625 fold_truth_not_expr (tree arg)
3627 tree type = TREE_TYPE (arg);
3628 enum tree_code code = TREE_CODE (arg);
3630 /* If this is a comparison, we can simply invert it, except for
3631 floating-point non-equality comparisons, in which case we just
3632 enclose a TRUTH_NOT_EXPR around what we have. */
3634 if (TREE_CODE_CLASS (code) == tcc_comparison)
3636 tree op_type = TREE_TYPE (TREE_OPERAND (arg, 0));
3637 if (FLOAT_TYPE_P (op_type)
3638 && flag_trapping_math
3639 && code != ORDERED_EXPR && code != UNORDERED_EXPR
3640 && code != NE_EXPR && code != EQ_EXPR)
3644 code = invert_tree_comparison (code,
3645 HONOR_NANS (TYPE_MODE (op_type)));
3646 if (code == ERROR_MARK)
3649 return build2 (code, type,
3650 TREE_OPERAND (arg, 0), TREE_OPERAND (arg, 1));
3657 return constant_boolean_node (integer_zerop (arg), type);
3659 case TRUTH_AND_EXPR:
3660 return build2 (TRUTH_OR_EXPR, type,
3661 invert_truthvalue (TREE_OPERAND (arg, 0)),
3662 invert_truthvalue (TREE_OPERAND (arg, 1)));
3665 return build2 (TRUTH_AND_EXPR, type,
3666 invert_truthvalue (TREE_OPERAND (arg, 0)),
3667 invert_truthvalue (TREE_OPERAND (arg, 1)));
3669 case TRUTH_XOR_EXPR:
3670 /* Here we can invert either operand. We invert the first operand
3671 unless the second operand is a TRUTH_NOT_EXPR in which case our
3672 result is the XOR of the first operand with the inside of the
3673 negation of the second operand. */
3675 if (TREE_CODE (TREE_OPERAND (arg, 1)) == TRUTH_NOT_EXPR)
3676 return build2 (TRUTH_XOR_EXPR, type, TREE_OPERAND (arg, 0),
3677 TREE_OPERAND (TREE_OPERAND (arg, 1), 0));
3679 return build2 (TRUTH_XOR_EXPR, type,
3680 invert_truthvalue (TREE_OPERAND (arg, 0)),
3681 TREE_OPERAND (arg, 1));
3683 case TRUTH_ANDIF_EXPR:
3684 return build2 (TRUTH_ORIF_EXPR, type,
3685 invert_truthvalue (TREE_OPERAND (arg, 0)),
3686 invert_truthvalue (TREE_OPERAND (arg, 1)));
3688 case TRUTH_ORIF_EXPR:
3689 return build2 (TRUTH_ANDIF_EXPR, type,
3690 invert_truthvalue (TREE_OPERAND (arg, 0)),
3691 invert_truthvalue (TREE_OPERAND (arg, 1)));
3693 case TRUTH_NOT_EXPR:
3694 return TREE_OPERAND (arg, 0);
3698 tree arg1 = TREE_OPERAND (arg, 1);
3699 tree arg2 = TREE_OPERAND (arg, 2);
3700 /* A COND_EXPR may have a throw as one operand, which
3701 then has void type. Just leave void operands
3703 return build3 (COND_EXPR, type, TREE_OPERAND (arg, 0),
3704 VOID_TYPE_P (TREE_TYPE (arg1))
3705 ? arg1 : invert_truthvalue (arg1),
3706 VOID_TYPE_P (TREE_TYPE (arg2))
3707 ? arg2 : invert_truthvalue (arg2));
3711 return build2 (COMPOUND_EXPR, type, TREE_OPERAND (arg, 0),
3712 invert_truthvalue (TREE_OPERAND (arg, 1)));
3714 case NON_LVALUE_EXPR:
3715 return invert_truthvalue (TREE_OPERAND (arg, 0));
3718 if (TREE_CODE (TREE_TYPE (arg)) == BOOLEAN_TYPE)
3719 return build1 (TRUTH_NOT_EXPR, type, arg);
3723 return build1 (TREE_CODE (arg), type,
3724 invert_truthvalue (TREE_OPERAND (arg, 0)));
3727 if (!integer_onep (TREE_OPERAND (arg, 1)))
3729 return build2 (EQ_EXPR, type, arg,
3730 build_int_cst (type, 0));
3733 return build1 (TRUTH_NOT_EXPR, type, arg);
3735 case CLEANUP_POINT_EXPR:
3736 return build1 (CLEANUP_POINT_EXPR, type,
3737 invert_truthvalue (TREE_OPERAND (arg, 0)));
3746 /* Return a simplified tree node for the truth-negation of ARG. This
3747 never alters ARG itself. We assume that ARG is an operation that
3748 returns a truth value (0 or 1).
3750 FIXME: one would think we would fold the result, but it causes
3751 problems with the dominator optimizer. */
3754 invert_truthvalue (tree arg)
3758 if (TREE_CODE (arg) == ERROR_MARK)
3761 tem = fold_truth_not_expr (arg);
3763 tem = build1 (TRUTH_NOT_EXPR, TREE_TYPE (arg), arg);
3768 /* Given a bit-wise operation CODE applied to ARG0 and ARG1, see if both
3769 operands are another bit-wise operation with a common input. If so,
3770 distribute the bit operations to save an operation and possibly two if
3771 constants are involved. For example, convert
3772 (A | B) & (A | C) into A | (B & C)
3773 Further simplification will occur if B and C are constants.
3775 If this optimization cannot be done, 0 will be returned. */
3778 distribute_bit_expr (enum tree_code code, tree type, tree arg0, tree arg1)
3783 if (TREE_CODE (arg0) != TREE_CODE (arg1)
3784 || TREE_CODE (arg0) == code
3785 || (TREE_CODE (arg0) != BIT_AND_EXPR
3786 && TREE_CODE (arg0) != BIT_IOR_EXPR))
3789 if (operand_equal_p (TREE_OPERAND (arg0, 0), TREE_OPERAND (arg1, 0), 0))
3791 common = TREE_OPERAND (arg0, 0);
3792 left = TREE_OPERAND (arg0, 1);
3793 right = TREE_OPERAND (arg1, 1);
3795 else if (operand_equal_p (TREE_OPERAND (arg0, 0), TREE_OPERAND (arg1, 1), 0))
3797 common = TREE_OPERAND (arg0, 0);
3798 left = TREE_OPERAND (arg0, 1);
3799 right = TREE_OPERAND (arg1, 0);
3801 else if (operand_equal_p (TREE_OPERAND (arg0, 1), TREE_OPERAND (arg1, 0), 0))
3803 common = TREE_OPERAND (arg0, 1);
3804 left = TREE_OPERAND (arg0, 0);
3805 right = TREE_OPERAND (arg1, 1);
3807 else if (operand_equal_p (TREE_OPERAND (arg0, 1), TREE_OPERAND (arg1, 1), 0))
3809 common = TREE_OPERAND (arg0, 1);
3810 left = TREE_OPERAND (arg0, 0);
3811 right = TREE_OPERAND (arg1, 0);
3816 return fold_build2 (TREE_CODE (arg0), type, common,
3817 fold_build2 (code, type, left, right));
3820 /* Knowing that ARG0 and ARG1 are both RDIV_EXPRs, simplify a binary operation
3821 with code CODE. This optimization is unsafe. */
3823 distribute_real_division (enum tree_code code, tree type, tree arg0, tree arg1)
3825 bool mul0 = TREE_CODE (arg0) == MULT_EXPR;
3826 bool mul1 = TREE_CODE (arg1) == MULT_EXPR;
3828 /* (A / C) +- (B / C) -> (A +- B) / C. */
3830 && operand_equal_p (TREE_OPERAND (arg0, 1),
3831 TREE_OPERAND (arg1, 1), 0))
3832 return fold_build2 (mul0 ? MULT_EXPR : RDIV_EXPR, type,
3833 fold_build2 (code, type,
3834 TREE_OPERAND (arg0, 0),
3835 TREE_OPERAND (arg1, 0)),
3836 TREE_OPERAND (arg0, 1));
3838 /* (A / C1) +- (A / C2) -> A * (1 / C1 +- 1 / C2). */
3839 if (operand_equal_p (TREE_OPERAND (arg0, 0),
3840 TREE_OPERAND (arg1, 0), 0)
3841 && TREE_CODE (TREE_OPERAND (arg0, 1)) == REAL_CST
3842 && TREE_CODE (TREE_OPERAND (arg1, 1)) == REAL_CST)
3844 REAL_VALUE_TYPE r0, r1;
3845 r0 = TREE_REAL_CST (TREE_OPERAND (arg0, 1));
3846 r1 = TREE_REAL_CST (TREE_OPERAND (arg1, 1));
3848 real_arithmetic (&r0, RDIV_EXPR, &dconst1, &r0);
3850 real_arithmetic (&r1, RDIV_EXPR, &dconst1, &r1);
3851 real_arithmetic (&r0, code, &r0, &r1);
3852 return fold_build2 (MULT_EXPR, type,
3853 TREE_OPERAND (arg0, 0),
3854 build_real (type, r0));
3860 /* Subroutine for fold_truthop: decode a field reference.
3862 If EXP is a comparison reference, we return the innermost reference.
3864 *PBITSIZE is set to the number of bits in the reference, *PBITPOS is
3865 set to the starting bit number.
3867 If the innermost field can be completely contained in a mode-sized
3868 unit, *PMODE is set to that mode. Otherwise, it is set to VOIDmode.
3870 *PVOLATILEP is set to 1 if the any expression encountered is volatile;
3871 otherwise it is not changed.
3873 *PUNSIGNEDP is set to the signedness of the field.
3875 *PMASK is set to the mask used. This is either contained in a
3876 BIT_AND_EXPR or derived from the width of the field.
3878 *PAND_MASK is set to the mask found in a BIT_AND_EXPR, if any.
3880 Return 0 if this is not a component reference or is one that we can't
3881 do anything with. */
3884 decode_field_reference (tree exp, HOST_WIDE_INT *pbitsize,
3885 HOST_WIDE_INT *pbitpos, enum machine_mode *pmode,
3886 int *punsignedp, int *pvolatilep,
3887 tree *pmask, tree *pand_mask)
3889 tree outer_type = 0;
3891 tree mask, inner, offset;
3893 unsigned int precision;
3895 /* All the optimizations using this function assume integer fields.
3896 There are problems with FP fields since the type_for_size call
3897 below can fail for, e.g., XFmode. */
3898 if (! INTEGRAL_TYPE_P (TREE_TYPE (exp)))
3901 /* We are interested in the bare arrangement of bits, so strip everything
3902 that doesn't affect the machine mode. However, record the type of the
3903 outermost expression if it may matter below. */
3904 if (TREE_CODE (exp) == NOP_EXPR
3905 || TREE_CODE (exp) == CONVERT_EXPR
3906 || TREE_CODE (exp) == NON_LVALUE_EXPR)
3907 outer_type = TREE_TYPE (exp);
3910 if (TREE_CODE (exp) == BIT_AND_EXPR)
3912 and_mask = TREE_OPERAND (exp, 1);
3913 exp = TREE_OPERAND (exp, 0);
3914 STRIP_NOPS (exp); STRIP_NOPS (and_mask);
3915 if (TREE_CODE (and_mask) != INTEGER_CST)
3919 inner = get_inner_reference (exp, pbitsize, pbitpos, &offset, pmode,
3920 punsignedp, pvolatilep, false);
3921 if ((inner == exp && and_mask == 0)
3922 || *pbitsize < 0 || offset != 0
3923 || TREE_CODE (inner) == PLACEHOLDER_EXPR)
3926 /* If the number of bits in the reference is the same as the bitsize of
3927 the outer type, then the outer type gives the signedness. Otherwise
3928 (in case of a small bitfield) the signedness is unchanged. */
3929 if (outer_type && *pbitsize == TYPE_PRECISION (outer_type))
3930 *punsignedp = TYPE_UNSIGNED (outer_type);
3932 /* Compute the mask to access the bitfield. */
3933 unsigned_type = lang_hooks.types.type_for_size (*pbitsize, 1);
3934 precision = TYPE_PRECISION (unsigned_type);
3936 mask = build_int_cst_type (unsigned_type, -1);
3938 mask = const_binop (LSHIFT_EXPR, mask, size_int (precision - *pbitsize), 0);
3939 mask = const_binop (RSHIFT_EXPR, mask, size_int (precision - *pbitsize), 0);
3941 /* Merge it with the mask we found in the BIT_AND_EXPR, if any. */
3943 mask = fold_build2 (BIT_AND_EXPR, unsigned_type,
3944 fold_convert (unsigned_type, and_mask), mask);
3947 *pand_mask = and_mask;
3951 /* Subroutine for fold: determine if VAL is the INTEGER_CONST that
3952 represents the sign bit of EXP's type. If EXP represents a sign
3953 or zero extension, also test VAL against the unextended type.
3954 The return value is the (sub)expression whose sign bit is VAL,
3955 or NULL_TREE otherwise. */
3958 sign_bit_p (tree exp, const_tree val)
3960 unsigned HOST_WIDE_INT mask_lo, lo;
3961 HOST_WIDE_INT mask_hi, hi;
3965 /* Tree EXP must have an integral type. */
3966 t = TREE_TYPE (exp);
3967 if (! INTEGRAL_TYPE_P (t))
3970 /* Tree VAL must be an integer constant. */
3971 if (TREE_CODE (val) != INTEGER_CST
3972 || TREE_OVERFLOW (val))
3975 width = TYPE_PRECISION (t);
3976 if (width > HOST_BITS_PER_WIDE_INT)
3978 hi = (unsigned HOST_WIDE_INT) 1 << (width - HOST_BITS_PER_WIDE_INT - 1);
3981 mask_hi = ((unsigned HOST_WIDE_INT) -1
3982 >> (2 * HOST_BITS_PER_WIDE_INT - width));
3988 lo = (unsigned HOST_WIDE_INT) 1 << (width - 1);
3991 mask_lo = ((unsigned HOST_WIDE_INT) -1
3992 >> (HOST_BITS_PER_WIDE_INT - width));
3995 /* We mask off those bits beyond TREE_TYPE (exp) so that we can
3996 treat VAL as if it were unsigned. */
3997 if ((TREE_INT_CST_HIGH (val) & mask_hi) == hi
3998 && (TREE_INT_CST_LOW (val) & mask_lo) == lo)
4001 /* Handle extension from a narrower type. */
4002 if (TREE_CODE (exp) == NOP_EXPR
4003 && TYPE_PRECISION (TREE_TYPE (TREE_OPERAND (exp, 0))) < width)
4004 return sign_bit_p (TREE_OPERAND (exp, 0), val);
4009 /* Subroutine for fold_truthop: determine if an operand is simple enough
4010 to be evaluated unconditionally. */
4013 simple_operand_p (const_tree exp)
4015 /* Strip any conversions that don't change the machine mode. */
4018 return (CONSTANT_CLASS_P (exp)
4019 || TREE_CODE (exp) == SSA_NAME
4021 && ! TREE_ADDRESSABLE (exp)
4022 && ! TREE_THIS_VOLATILE (exp)
4023 && ! DECL_NONLOCAL (exp)
4024 /* Don't regard global variables as simple. They may be
4025 allocated in ways unknown to the compiler (shared memory,
4026 #pragma weak, etc). */
4027 && ! TREE_PUBLIC (exp)
4028 && ! DECL_EXTERNAL (exp)
4029 /* Loading a static variable is unduly expensive, but global
4030 registers aren't expensive. */
4031 && (! TREE_STATIC (exp) || DECL_REGISTER (exp))));
4034 /* The following functions are subroutines to fold_range_test and allow it to
4035 try to change a logical combination of comparisons into a range test.
4038 X == 2 || X == 3 || X == 4 || X == 5
4042 (unsigned) (X - 2) <= 3
4044 We describe each set of comparisons as being either inside or outside
4045 a range, using a variable named like IN_P, and then describe the
4046 range with a lower and upper bound. If one of the bounds is omitted,
4047 it represents either the highest or lowest value of the type.
4049 In the comments below, we represent a range by two numbers in brackets
4050 preceded by a "+" to designate being inside that range, or a "-" to
4051 designate being outside that range, so the condition can be inverted by
4052 flipping the prefix. An omitted bound is represented by a "-". For
4053 example, "- [-, 10]" means being outside the range starting at the lowest
4054 possible value and ending at 10, in other words, being greater than 10.
4055 The range "+ [-, -]" is always true and hence the range "- [-, -]" is
4058 We set up things so that the missing bounds are handled in a consistent
4059 manner so neither a missing bound nor "true" and "false" need to be
4060 handled using a special case. */
4062 /* Return the result of applying CODE to ARG0 and ARG1, but handle the case
4063 of ARG0 and/or ARG1 being omitted, meaning an unlimited range. UPPER0_P
4064 and UPPER1_P are nonzero if the respective argument is an upper bound
4065 and zero for a lower. TYPE, if nonzero, is the type of the result; it
4066 must be specified for a comparison. ARG1 will be converted to ARG0's
4067 type if both are specified. */
4070 range_binop (enum tree_code code, tree type, tree arg0, int upper0_p,
4071 tree arg1, int upper1_p)
4077 /* If neither arg represents infinity, do the normal operation.
4078 Else, if not a comparison, return infinity. Else handle the special
4079 comparison rules. Note that most of the cases below won't occur, but
4080 are handled for consistency. */
4082 if (arg0 != 0 && arg1 != 0)
4084 tem = fold_build2 (code, type != 0 ? type : TREE_TYPE (arg0),
4085 arg0, fold_convert (TREE_TYPE (arg0), arg1));
4087 return TREE_CODE (tem) == INTEGER_CST ? tem : 0;
4090 if (TREE_CODE_CLASS (code) != tcc_comparison)
4093 /* Set SGN[01] to -1 if ARG[01] is a lower bound, 1 for upper, and 0
4094 for neither. In real maths, we cannot assume open ended ranges are
4095 the same. But, this is computer arithmetic, where numbers are finite.
4096 We can therefore make the transformation of any unbounded range with
4097 the value Z, Z being greater than any representable number. This permits
4098 us to treat unbounded ranges as equal. */
4099 sgn0 = arg0 != 0 ? 0 : (upper0_p ? 1 : -1);
4100 sgn1 = arg1 != 0 ? 0 : (upper1_p ? 1 : -1);
4104 result = sgn0 == sgn1;
4107 result = sgn0 != sgn1;
4110 result = sgn0 < sgn1;
4113 result = sgn0 <= sgn1;
4116 result = sgn0 > sgn1;
4119 result = sgn0 >= sgn1;
4125 return constant_boolean_node (result, type);
4128 /* Given EXP, a logical expression, set the range it is testing into
4129 variables denoted by PIN_P, PLOW, and PHIGH. Return the expression
4130 actually being tested. *PLOW and *PHIGH will be made of the same
4131 type as the returned expression. If EXP is not a comparison, we
4132 will most likely not be returning a useful value and range. Set
4133 *STRICT_OVERFLOW_P to true if the return value is only valid
4134 because signed overflow is undefined; otherwise, do not change
4135 *STRICT_OVERFLOW_P. */
4138 make_range (tree exp, int *pin_p, tree *plow, tree *phigh,
4139 bool *strict_overflow_p)
4141 enum tree_code code;
4142 tree arg0 = NULL_TREE, arg1 = NULL_TREE;
4143 tree exp_type = NULL_TREE, arg0_type = NULL_TREE;
4145 tree low, high, n_low, n_high;
4147 /* Start with simply saying "EXP != 0" and then look at the code of EXP
4148 and see if we can refine the range. Some of the cases below may not
4149 happen, but it doesn't seem worth worrying about this. We "continue"
4150 the outer loop when we've changed something; otherwise we "break"
4151 the switch, which will "break" the while. */
4154 low = high = build_int_cst (TREE_TYPE (exp), 0);
4158 code = TREE_CODE (exp);
4159 exp_type = TREE_TYPE (exp);
4161 if (IS_EXPR_CODE_CLASS (TREE_CODE_CLASS (code)))
4163 if (TREE_OPERAND_LENGTH (exp) > 0)
4164 arg0 = TREE_OPERAND (exp, 0);
4165 if (TREE_CODE_CLASS (code) == tcc_comparison
4166 || TREE_CODE_CLASS (code) == tcc_unary
4167 || TREE_CODE_CLASS (code) == tcc_binary)
4168 arg0_type = TREE_TYPE (arg0);
4169 if (TREE_CODE_CLASS (code) == tcc_binary
4170 || TREE_CODE_CLASS (code) == tcc_comparison
4171 || (TREE_CODE_CLASS (code) == tcc_expression
4172 && TREE_OPERAND_LENGTH (exp) > 1))
4173 arg1 = TREE_OPERAND (exp, 1);
4178 case TRUTH_NOT_EXPR:
4179 in_p = ! in_p, exp = arg0;
4182 case EQ_EXPR: case NE_EXPR:
4183 case LT_EXPR: case LE_EXPR: case GE_EXPR: case GT_EXPR:
4184 /* We can only do something if the range is testing for zero
4185 and if the second operand is an integer constant. Note that
4186 saying something is "in" the range we make is done by
4187 complementing IN_P since it will set in the initial case of
4188 being not equal to zero; "out" is leaving it alone. */
4189 if (low == 0 || high == 0
4190 || ! integer_zerop (low) || ! integer_zerop (high)
4191 || TREE_CODE (arg1) != INTEGER_CST)
4196 case NE_EXPR: /* - [c, c] */
4199 case EQ_EXPR: /* + [c, c] */
4200 in_p = ! in_p, low = high = arg1;
4202 case GT_EXPR: /* - [-, c] */
4203 low = 0, high = arg1;
4205 case GE_EXPR: /* + [c, -] */
4206 in_p = ! in_p, low = arg1, high = 0;
4208 case LT_EXPR: /* - [c, -] */
4209 low = arg1, high = 0;
4211 case LE_EXPR: /* + [-, c] */
4212 in_p = ! in_p, low = 0, high = arg1;
4218 /* If this is an unsigned comparison, we also know that EXP is
4219 greater than or equal to zero. We base the range tests we make
4220 on that fact, so we record it here so we can parse existing
4221 range tests. We test arg0_type since often the return type
4222 of, e.g. EQ_EXPR, is boolean. */
4223 if (TYPE_UNSIGNED (arg0_type) && (low == 0 || high == 0))
4225 if (! merge_ranges (&n_in_p, &n_low, &n_high,
4227 build_int_cst (arg0_type, 0),
4231 in_p = n_in_p, low = n_low, high = n_high;
4233 /* If the high bound is missing, but we have a nonzero low
4234 bound, reverse the range so it goes from zero to the low bound
4236 if (high == 0 && low && ! integer_zerop (low))
4239 high = range_binop (MINUS_EXPR, NULL_TREE, low, 0,
4240 integer_one_node, 0);
4241 low = build_int_cst (arg0_type, 0);
4249 /* (-x) IN [a,b] -> x in [-b, -a] */
4250 n_low = range_binop (MINUS_EXPR, exp_type,
4251 build_int_cst (exp_type, 0),
4253 n_high = range_binop (MINUS_EXPR, exp_type,
4254 build_int_cst (exp_type, 0),
4256 low = n_low, high = n_high;
4262 exp = build2 (MINUS_EXPR, exp_type, negate_expr (arg0),
4263 build_int_cst (exp_type, 1));
4266 case PLUS_EXPR: case MINUS_EXPR:
4267 if (TREE_CODE (arg1) != INTEGER_CST)
4270 /* If flag_wrapv and ARG0_TYPE is signed, then we cannot
4271 move a constant to the other side. */
4272 if (!TYPE_UNSIGNED (arg0_type)
4273 && !TYPE_OVERFLOW_UNDEFINED (arg0_type))
4276 /* If EXP is signed, any overflow in the computation is undefined,
4277 so we don't worry about it so long as our computations on
4278 the bounds don't overflow. For unsigned, overflow is defined
4279 and this is exactly the right thing. */
4280 n_low = range_binop (code == MINUS_EXPR ? PLUS_EXPR : MINUS_EXPR,
4281 arg0_type, low, 0, arg1, 0);
4282 n_high = range_binop (code == MINUS_EXPR ? PLUS_EXPR : MINUS_EXPR,
4283 arg0_type, high, 1, arg1, 0);
4284 if ((n_low != 0 && TREE_OVERFLOW (n_low))
4285 || (n_high != 0 && TREE_OVERFLOW (n_high)))
4288 if (TYPE_OVERFLOW_UNDEFINED (arg0_type))
4289 *strict_overflow_p = true;
4291 /* Check for an unsigned range which has wrapped around the maximum
4292 value thus making n_high < n_low, and normalize it. */
4293 if (n_low && n_high && tree_int_cst_lt (n_high, n_low))
4295 low = range_binop (PLUS_EXPR, arg0_type, n_high, 0,
4296 integer_one_node, 0);
4297 high = range_binop (MINUS_EXPR, arg0_type, n_low, 0,
4298 integer_one_node, 0);
4300 /* If the range is of the form +/- [ x+1, x ], we won't
4301 be able to normalize it. But then, it represents the
4302 whole range or the empty set, so make it
4304 if (tree_int_cst_equal (n_low, low)
4305 && tree_int_cst_equal (n_high, high))
4311 low = n_low, high = n_high;
4316 case NOP_EXPR: case NON_LVALUE_EXPR: case CONVERT_EXPR:
4317 if (TYPE_PRECISION (arg0_type) > TYPE_PRECISION (exp_type))
4320 if (! INTEGRAL_TYPE_P (arg0_type)
4321 || (low != 0 && ! int_fits_type_p (low, arg0_type))
4322 || (high != 0 && ! int_fits_type_p (high, arg0_type)))
4325 n_low = low, n_high = high;
4328 n_low = fold_convert (arg0_type, n_low);
4331 n_high = fold_convert (arg0_type, n_high);
4334 /* If we're converting arg0 from an unsigned type, to exp,
4335 a signed type, we will be doing the comparison as unsigned.
4336 The tests above have already verified that LOW and HIGH
4339 So we have to ensure that we will handle large unsigned
4340 values the same way that the current signed bounds treat
4343 if (!TYPE_UNSIGNED (exp_type) && TYPE_UNSIGNED (arg0_type))
4347 /* For fixed-point modes, we need to pass the saturating flag
4348 as the 2nd parameter. */
4349 if (ALL_FIXED_POINT_MODE_P (TYPE_MODE (arg0_type)))
4350 equiv_type = lang_hooks.types.type_for_mode
4351 (TYPE_MODE (arg0_type),
4352 TYPE_SATURATING (arg0_type));
4354 equiv_type = lang_hooks.types.type_for_mode
4355 (TYPE_MODE (arg0_type), 1);
4357 /* A range without an upper bound is, naturally, unbounded.
4358 Since convert would have cropped a very large value, use
4359 the max value for the destination type. */
4361 = TYPE_MAX_VALUE (equiv_type) ? TYPE_MAX_VALUE (equiv_type)
4362 : TYPE_MAX_VALUE (arg0_type);
4364 if (TYPE_PRECISION (exp_type) == TYPE_PRECISION (arg0_type))
4365 high_positive = fold_build2 (RSHIFT_EXPR, arg0_type,
4366 fold_convert (arg0_type,
4368 build_int_cst (arg0_type, 1));
4370 /* If the low bound is specified, "and" the range with the
4371 range for which the original unsigned value will be
4375 if (! merge_ranges (&n_in_p, &n_low, &n_high,
4376 1, n_low, n_high, 1,
4377 fold_convert (arg0_type,
4382 in_p = (n_in_p == in_p);
4386 /* Otherwise, "or" the range with the range of the input
4387 that will be interpreted as negative. */
4388 if (! merge_ranges (&n_in_p, &n_low, &n_high,
4389 0, n_low, n_high, 1,
4390 fold_convert (arg0_type,
4395 in_p = (in_p != n_in_p);
4400 low = n_low, high = n_high;
4410 /* If EXP is a constant, we can evaluate whether this is true or false. */
4411 if (TREE_CODE (exp) == INTEGER_CST)
4413 in_p = in_p == (integer_onep (range_binop (GE_EXPR, integer_type_node,
4415 && integer_onep (range_binop (LE_EXPR, integer_type_node,
4421 *pin_p = in_p, *plow = low, *phigh = high;
4425 /* Given a range, LOW, HIGH, and IN_P, an expression, EXP, and a result
4426 type, TYPE, return an expression to test if EXP is in (or out of, depending
4427 on IN_P) the range. Return 0 if the test couldn't be created. */
4430 build_range_check (tree type, tree exp, int in_p, tree low, tree high)
4432 tree etype = TREE_TYPE (exp);
4435 #ifdef HAVE_canonicalize_funcptr_for_compare
4436 /* Disable this optimization for function pointer expressions
4437 on targets that require function pointer canonicalization. */
4438 if (HAVE_canonicalize_funcptr_for_compare
4439 && TREE_CODE (etype) == POINTER_TYPE
4440 && TREE_CODE (TREE_TYPE (etype)) == FUNCTION_TYPE)
4446 value = build_range_check (type, exp, 1, low, high);
4448 return invert_truthvalue (value);
4453 if (low == 0 && high == 0)
4454 return build_int_cst (type, 1);
4457 return fold_build2 (LE_EXPR, type, exp,
4458 fold_convert (etype, high));
4461 return fold_build2 (GE_EXPR, type, exp,
4462 fold_convert (etype, low));
4464 if (operand_equal_p (low, high, 0))
4465 return fold_build2 (EQ_EXPR, type, exp,
4466 fold_convert (etype, low));
4468 if (integer_zerop (low))
4470 if (! TYPE_UNSIGNED (etype))
4472 etype = unsigned_type_for (etype);
4473 high = fold_convert (etype, high);
4474 exp = fold_convert (etype, exp);
4476 return build_range_check (type, exp, 1, 0, high);
4479 /* Optimize (c>=1) && (c<=127) into (signed char)c > 0. */
4480 if (integer_onep (low) && TREE_CODE (high) == INTEGER_CST)
4482 unsigned HOST_WIDE_INT lo;
4486 prec = TYPE_PRECISION (etype);
4487 if (prec <= HOST_BITS_PER_WIDE_INT)
4490 lo = ((unsigned HOST_WIDE_INT) 1 << (prec - 1)) - 1;
4494 hi = ((HOST_WIDE_INT) 1 << (prec - HOST_BITS_PER_WIDE_INT - 1)) - 1;
4495 lo = (unsigned HOST_WIDE_INT) -1;
4498 if (TREE_INT_CST_HIGH (high) == hi && TREE_INT_CST_LOW (high) == lo)
4500 if (TYPE_UNSIGNED (etype))
4502 etype = signed_type_for (etype);
4503 exp = fold_convert (etype, exp);
4505 return fold_build2 (GT_EXPR, type, exp,
4506 build_int_cst (etype, 0));
4510 /* Optimize (c>=low) && (c<=high) into (c-low>=0) && (c-low<=high-low).
4511 This requires wrap-around arithmetics for the type of the expression. */
4512 switch (TREE_CODE (etype))
4515 /* There is no requirement that LOW be within the range of ETYPE
4516 if the latter is a subtype. It must, however, be within the base
4517 type of ETYPE. So be sure we do the subtraction in that type. */
4518 if (TREE_TYPE (etype))
4519 etype = TREE_TYPE (etype);
4524 etype = lang_hooks.types.type_for_size (TYPE_PRECISION (etype),
4525 TYPE_UNSIGNED (etype));
4532 /* If we don't have wrap-around arithmetics upfront, try to force it. */
4533 if (TREE_CODE (etype) == INTEGER_TYPE
4534 && !TYPE_OVERFLOW_WRAPS (etype))
4536 tree utype, minv, maxv;
4538 /* Check if (unsigned) INT_MAX + 1 == (unsigned) INT_MIN
4539 for the type in question, as we rely on this here. */
4540 utype = unsigned_type_for (etype);
4541 maxv = fold_convert (utype, TYPE_MAX_VALUE (etype));
4542 maxv = range_binop (PLUS_EXPR, NULL_TREE, maxv, 1,
4543 integer_one_node, 1);
4544 minv = fold_convert (utype, TYPE_MIN_VALUE (etype));
4546 if (integer_zerop (range_binop (NE_EXPR, integer_type_node,
4553 high = fold_convert (etype, high);
4554 low = fold_convert (etype, low);
4555 exp = fold_convert (etype, exp);
4557 value = const_binop (MINUS_EXPR, high, low, 0);
4560 if (POINTER_TYPE_P (etype))
4562 if (value != 0 && !TREE_OVERFLOW (value))
4564 low = fold_convert (sizetype, low);
4565 low = fold_build1 (NEGATE_EXPR, sizetype, low);
4566 return build_range_check (type,
4567 fold_build2 (POINTER_PLUS_EXPR, etype, exp, low),
4568 1, build_int_cst (etype, 0), value);
4573 if (value != 0 && !TREE_OVERFLOW (value))
4574 return build_range_check (type,
4575 fold_build2 (MINUS_EXPR, etype, exp, low),
4576 1, build_int_cst (etype, 0), value);
4581 /* Return the predecessor of VAL in its type, handling the infinite case. */
4584 range_predecessor (tree val)
4586 tree type = TREE_TYPE (val);
4588 if (INTEGRAL_TYPE_P (type)
4589 && operand_equal_p (val, TYPE_MIN_VALUE (type), 0))
4592 return range_binop (MINUS_EXPR, NULL_TREE, val, 0, integer_one_node, 0);
4595 /* Return the successor of VAL in its type, handling the infinite case. */
4598 range_successor (tree val)
4600 tree type = TREE_TYPE (val);
4602 if (INTEGRAL_TYPE_P (type)
4603 && operand_equal_p (val, TYPE_MAX_VALUE (type), 0))
4606 return range_binop (PLUS_EXPR, NULL_TREE, val, 0, integer_one_node, 0);
4609 /* Given two ranges, see if we can merge them into one. Return 1 if we
4610 can, 0 if we can't. Set the output range into the specified parameters. */
4613 merge_ranges (int *pin_p, tree *plow, tree *phigh, int in0_p, tree low0,
4614 tree high0, int in1_p, tree low1, tree high1)
4622 int lowequal = ((low0 == 0 && low1 == 0)
4623 || integer_onep (range_binop (EQ_EXPR, integer_type_node,
4624 low0, 0, low1, 0)));
4625 int highequal = ((high0 == 0 && high1 == 0)
4626 || integer_onep (range_binop (EQ_EXPR, integer_type_node,
4627 high0, 1, high1, 1)));
4629 /* Make range 0 be the range that starts first, or ends last if they
4630 start at the same value. Swap them if it isn't. */
4631 if (integer_onep (range_binop (GT_EXPR, integer_type_node,
4634 && integer_onep (range_binop (GT_EXPR, integer_type_node,
4635 high1, 1, high0, 1))))
4637 temp = in0_p, in0_p = in1_p, in1_p = temp;
4638 tem = low0, low0 = low1, low1 = tem;
4639 tem = high0, high0 = high1, high1 = tem;
4642 /* Now flag two cases, whether the ranges are disjoint or whether the
4643 second range is totally subsumed in the first. Note that the tests
4644 below are simplified by the ones above. */
4645 no_overlap = integer_onep (range_binop (LT_EXPR, integer_type_node,
4646 high0, 1, low1, 0));
4647 subset = integer_onep (range_binop (LE_EXPR, integer_type_node,
4648 high1, 1, high0, 1));
4650 /* We now have four cases, depending on whether we are including or
4651 excluding the two ranges. */
4654 /* If they don't overlap, the result is false. If the second range
4655 is a subset it is the result. Otherwise, the range is from the start
4656 of the second to the end of the first. */
4658 in_p = 0, low = high = 0;
4660 in_p = 1, low = low1, high = high1;
4662 in_p = 1, low = low1, high = high0;
4665 else if (in0_p && ! in1_p)
4667 /* If they don't overlap, the result is the first range. If they are
4668 equal, the result is false. If the second range is a subset of the
4669 first, and the ranges begin at the same place, we go from just after
4670 the end of the second range to the end of the first. If the second
4671 range is not a subset of the first, or if it is a subset and both
4672 ranges end at the same place, the range starts at the start of the
4673 first range and ends just before the second range.
4674 Otherwise, we can't describe this as a single range. */
4676 in_p = 1, low = low0, high = high0;
4677 else if (lowequal && highequal)
4678 in_p = 0, low = high = 0;
4679 else if (subset && lowequal)
4681 low = range_successor (high1);
4686 /* We are in the weird situation where high0 > high1 but
4687 high1 has no successor. Punt. */
4691 else if (! subset || highequal)
4694 high = range_predecessor (low1);
4698 /* low0 < low1 but low1 has no predecessor. Punt. */
4706 else if (! in0_p && in1_p)
4708 /* If they don't overlap, the result is the second range. If the second
4709 is a subset of the first, the result is false. Otherwise,
4710 the range starts just after the first range and ends at the
4711 end of the second. */
4713 in_p = 1, low = low1, high = high1;
4714 else if (subset || highequal)
4715 in_p = 0, low = high = 0;
4718 low = range_successor (high0);
4723 /* high1 > high0 but high0 has no successor. Punt. */
4731 /* The case where we are excluding both ranges. Here the complex case
4732 is if they don't overlap. In that case, the only time we have a
4733 range is if they are adjacent. If the second is a subset of the
4734 first, the result is the first. Otherwise, the range to exclude
4735 starts at the beginning of the first range and ends at the end of the
4739 if (integer_onep (range_binop (EQ_EXPR, integer_type_node,
4740 range_successor (high0),
4742 in_p = 0, low = low0, high = high1;
4745 /* Canonicalize - [min, x] into - [-, x]. */
4746 if (low0 && TREE_CODE (low0) == INTEGER_CST)
4747 switch (TREE_CODE (TREE_TYPE (low0)))
4750 if (TYPE_PRECISION (TREE_TYPE (low0))
4751 != GET_MODE_BITSIZE (TYPE_MODE (TREE_TYPE (low0))))
4755 if (tree_int_cst_equal (low0,
4756 TYPE_MIN_VALUE (TREE_TYPE (low0))))
4760 if (TYPE_UNSIGNED (TREE_TYPE (low0))
4761 && integer_zerop (low0))
4768 /* Canonicalize - [x, max] into - [x, -]. */
4769 if (high1 && TREE_CODE (high1) == INTEGER_CST)
4770 switch (TREE_CODE (TREE_TYPE (high1)))
4773 if (TYPE_PRECISION (TREE_TYPE (high1))
4774 != GET_MODE_BITSIZE (TYPE_MODE (TREE_TYPE (high1))))
4778 if (tree_int_cst_equal (high1,
4779 TYPE_MAX_VALUE (TREE_TYPE (high1))))
4783 if (TYPE_UNSIGNED (TREE_TYPE (high1))
4784 && integer_zerop (range_binop (PLUS_EXPR, NULL_TREE,
4786 integer_one_node, 1)))
4793 /* The ranges might be also adjacent between the maximum and
4794 minimum values of the given type. For
4795 - [{min,-}, x] and - [y, {max,-}] ranges where x + 1 < y
4796 return + [x + 1, y - 1]. */
4797 if (low0 == 0 && high1 == 0)
4799 low = range_successor (high0);
4800 high = range_predecessor (low1);
4801 if (low == 0 || high == 0)
4811 in_p = 0, low = low0, high = high0;
4813 in_p = 0, low = low0, high = high1;
4816 *pin_p = in_p, *plow = low, *phigh = high;
4821 /* Subroutine of fold, looking inside expressions of the form
4822 A op B ? A : C, where ARG0, ARG1 and ARG2 are the three operands
4823 of the COND_EXPR. This function is being used also to optimize
4824 A op B ? C : A, by reversing the comparison first.
4826 Return a folded expression whose code is not a COND_EXPR
4827 anymore, or NULL_TREE if no folding opportunity is found. */
4830 fold_cond_expr_with_comparison (tree type, tree arg0, tree arg1, tree arg2)
4832 enum tree_code comp_code = TREE_CODE (arg0);
4833 tree arg00 = TREE_OPERAND (arg0, 0);
4834 tree arg01 = TREE_OPERAND (arg0, 1);
4835 tree arg1_type = TREE_TYPE (arg1);
4841 /* If we have A op 0 ? A : -A, consider applying the following
4844 A == 0? A : -A same as -A
4845 A != 0? A : -A same as A
4846 A >= 0? A : -A same as abs (A)
4847 A > 0? A : -A same as abs (A)
4848 A <= 0? A : -A same as -abs (A)
4849 A < 0? A : -A same as -abs (A)
4851 None of these transformations work for modes with signed
4852 zeros. If A is +/-0, the first two transformations will
4853 change the sign of the result (from +0 to -0, or vice
4854 versa). The last four will fix the sign of the result,
4855 even though the original expressions could be positive or
4856 negative, depending on the sign of A.
4858 Note that all these transformations are correct if A is
4859 NaN, since the two alternatives (A and -A) are also NaNs. */
4860 if (!HONOR_SIGNED_ZEROS (TYPE_MODE (type))
4861 && (FLOAT_TYPE_P (TREE_TYPE (arg01))
4862 ? real_zerop (arg01)
4863 : integer_zerop (arg01))
4864 && ((TREE_CODE (arg2) == NEGATE_EXPR
4865 && operand_equal_p (TREE_OPERAND (arg2, 0), arg1, 0))
4866 /* In the case that A is of the form X-Y, '-A' (arg2) may
4867 have already been folded to Y-X, check for that. */
4868 || (TREE_CODE (arg1) == MINUS_EXPR
4869 && TREE_CODE (arg2) == MINUS_EXPR
4870 && operand_equal_p (TREE_OPERAND (arg1, 0),
4871 TREE_OPERAND (arg2, 1), 0)
4872 && operand_equal_p (TREE_OPERAND (arg1, 1),
4873 TREE_OPERAND (arg2, 0), 0))))
4878 tem = fold_convert (arg1_type, arg1);
4879 return pedantic_non_lvalue (fold_convert (type, negate_expr (tem)));
4882 return pedantic_non_lvalue (fold_convert (type, arg1));
4885 if (flag_trapping_math)
4890 if (TYPE_UNSIGNED (TREE_TYPE (arg1)))
4891 arg1 = fold_convert (signed_type_for
4892 (TREE_TYPE (arg1)), arg1);
4893 tem = fold_build1 (ABS_EXPR, TREE_TYPE (arg1), arg1);
4894 return pedantic_non_lvalue (fold_convert (type, tem));
4897 if (flag_trapping_math)
4901 if (TYPE_UNSIGNED (TREE_TYPE (arg1)))
4902 arg1 = fold_convert (signed_type_for
4903 (TREE_TYPE (arg1)), arg1);
4904 tem = fold_build1 (ABS_EXPR, TREE_TYPE (arg1), arg1);
4905 return negate_expr (fold_convert (type, tem));
4907 gcc_assert (TREE_CODE_CLASS (comp_code) == tcc_comparison);
4911 /* A != 0 ? A : 0 is simply A, unless A is -0. Likewise
4912 A == 0 ? A : 0 is always 0 unless A is -0. Note that
4913 both transformations are correct when A is NaN: A != 0
4914 is then true, and A == 0 is false. */
4916 if (!HONOR_SIGNED_ZEROS (TYPE_MODE (type))
4917 && integer_zerop (arg01) && integer_zerop (arg2))
4919 if (comp_code == NE_EXPR)
4920 return pedantic_non_lvalue (fold_convert (type, arg1));
4921 else if (comp_code == EQ_EXPR)
4922 return build_int_cst (type, 0);
4925 /* Try some transformations of A op B ? A : B.
4927 A == B? A : B same as B
4928 A != B? A : B same as A
4929 A >= B? A : B same as max (A, B)
4930 A > B? A : B same as max (B, A)
4931 A <= B? A : B same as min (A, B)
4932 A < B? A : B same as min (B, A)
4934 As above, these transformations don't work in the presence
4935 of signed zeros. For example, if A and B are zeros of
4936 opposite sign, the first two transformations will change
4937 the sign of the result. In the last four, the original
4938 expressions give different results for (A=+0, B=-0) and
4939 (A=-0, B=+0), but the transformed expressions do not.
4941 The first two transformations are correct if either A or B
4942 is a NaN. In the first transformation, the condition will
4943 be false, and B will indeed be chosen. In the case of the
4944 second transformation, the condition A != B will be true,
4945 and A will be chosen.
4947 The conversions to max() and min() are not correct if B is
4948 a number and A is not. The conditions in the original
4949 expressions will be false, so all four give B. The min()
4950 and max() versions would give a NaN instead. */
4951 if (!HONOR_SIGNED_ZEROS (TYPE_MODE (type))
4952 && operand_equal_for_comparison_p (arg01, arg2, arg00)
4953 /* Avoid these transformations if the COND_EXPR may be used
4954 as an lvalue in the C++ front-end. PR c++/19199. */
4956 || (strcmp (lang_hooks.name, "GNU C++") != 0
4957 && strcmp (lang_hooks.name, "GNU Objective-C++") != 0)
4958 || ! maybe_lvalue_p (arg1)
4959 || ! maybe_lvalue_p (arg2)))
4961 tree comp_op0 = arg00;
4962 tree comp_op1 = arg01;
4963 tree comp_type = TREE_TYPE (comp_op0);
4965 /* Avoid adding NOP_EXPRs in case this is an lvalue. */
4966 if (TYPE_MAIN_VARIANT (comp_type) == TYPE_MAIN_VARIANT (type))
4976 return pedantic_non_lvalue (fold_convert (type, arg2));
4978 return pedantic_non_lvalue (fold_convert (type, arg1));
4983 /* In C++ a ?: expression can be an lvalue, so put the
4984 operand which will be used if they are equal first
4985 so that we can convert this back to the
4986 corresponding COND_EXPR. */
4987 if (!HONOR_NANS (TYPE_MODE (TREE_TYPE (arg1))))
4989 comp_op0 = fold_convert (comp_type, comp_op0);
4990 comp_op1 = fold_convert (comp_type, comp_op1);
4991 tem = (comp_code == LE_EXPR || comp_code == UNLE_EXPR)
4992 ? fold_build2 (MIN_EXPR, comp_type, comp_op0, comp_op1)
4993 : fold_build2 (MIN_EXPR, comp_type, comp_op1, comp_op0);
4994 return pedantic_non_lvalue (fold_convert (type, tem));
5001 if (!HONOR_NANS (TYPE_MODE (TREE_TYPE (arg1))))
5003 comp_op0 = fold_convert (comp_type, comp_op0);
5004 comp_op1 = fold_convert (comp_type, comp_op1);
5005 tem = (comp_code == GE_EXPR || comp_code == UNGE_EXPR)
5006 ? fold_build2 (MAX_EXPR, comp_type, comp_op0, comp_op1)
5007 : fold_build2 (MAX_EXPR, comp_type, comp_op1, comp_op0);
5008 return pedantic_non_lvalue (fold_convert (type, tem));
5012 if (!HONOR_NANS (TYPE_MODE (TREE_TYPE (arg1))))
5013 return pedantic_non_lvalue (fold_convert (type, arg2));
5016 if (!HONOR_NANS (TYPE_MODE (TREE_TYPE (arg1))))
5017 return pedantic_non_lvalue (fold_convert (type, arg1));
5020 gcc_assert (TREE_CODE_CLASS (comp_code) == tcc_comparison);
5025 /* If this is A op C1 ? A : C2 with C1 and C2 constant integers,
5026 we might still be able to simplify this. For example,
5027 if C1 is one less or one more than C2, this might have started
5028 out as a MIN or MAX and been transformed by this function.
5029 Only good for INTEGER_TYPEs, because we need TYPE_MAX_VALUE. */
5031 if (INTEGRAL_TYPE_P (type)
5032 && TREE_CODE (arg01) == INTEGER_CST
5033 && TREE_CODE (arg2) == INTEGER_CST)
5037 /* We can replace A with C1 in this case. */
5038 arg1 = fold_convert (type, arg01);
5039 return fold_build3 (COND_EXPR, type, arg0, arg1, arg2);
5042 /* If C1 is C2 + 1, this is min(A, C2). */
5043 if (! operand_equal_p (arg2, TYPE_MAX_VALUE (type),
5045 && operand_equal_p (arg01,
5046 const_binop (PLUS_EXPR, arg2,
5047 build_int_cst (type, 1), 0),
5049 return pedantic_non_lvalue (fold_build2 (MIN_EXPR,
5051 fold_convert (type, arg1),
5056 /* If C1 is C2 - 1, this is min(A, C2). */
5057 if (! operand_equal_p (arg2, TYPE_MIN_VALUE (type),
5059 && operand_equal_p (arg01,
5060 const_binop (MINUS_EXPR, arg2,
5061 build_int_cst (type, 1), 0),
5063 return pedantic_non_lvalue (fold_build2 (MIN_EXPR,
5065 fold_convert (type, arg1),
5070 /* If C1 is C2 - 1, this is max(A, C2). */
5071 if (! operand_equal_p (arg2, TYPE_MIN_VALUE (type),
5073 && operand_equal_p (arg01,
5074 const_binop (MINUS_EXPR, arg2,
5075 build_int_cst (type, 1), 0),
5077 return pedantic_non_lvalue (fold_build2 (MAX_EXPR,
5079 fold_convert (type, arg1),
5084 /* If C1 is C2 + 1, this is max(A, C2). */
5085 if (! operand_equal_p (arg2, TYPE_MAX_VALUE (type),
5087 && operand_equal_p (arg01,
5088 const_binop (PLUS_EXPR, arg2,
5089 build_int_cst (type, 1), 0),
5091 return pedantic_non_lvalue (fold_build2 (MAX_EXPR,
5093 fold_convert (type, arg1),
5107 #ifndef LOGICAL_OP_NON_SHORT_CIRCUIT
5108 #define LOGICAL_OP_NON_SHORT_CIRCUIT (BRANCH_COST >= 2)
5111 /* EXP is some logical combination of boolean tests. See if we can
5112 merge it into some range test. Return the new tree if so. */
5115 fold_range_test (enum tree_code code, tree type, tree op0, tree op1)
5117 int or_op = (code == TRUTH_ORIF_EXPR
5118 || code == TRUTH_OR_EXPR);
5119 int in0_p, in1_p, in_p;
5120 tree low0, low1, low, high0, high1, high;
5121 bool strict_overflow_p = false;
5122 tree lhs = make_range (op0, &in0_p, &low0, &high0, &strict_overflow_p);
5123 tree rhs = make_range (op1, &in1_p, &low1, &high1, &strict_overflow_p);
5125 const char * const warnmsg = G_("assuming signed overflow does not occur "
5126 "when simplifying range test");
5128 /* If this is an OR operation, invert both sides; we will invert
5129 again at the end. */
5131 in0_p = ! in0_p, in1_p = ! in1_p;
5133 /* If both expressions are the same, if we can merge the ranges, and we
5134 can build the range test, return it or it inverted. If one of the
5135 ranges is always true or always false, consider it to be the same
5136 expression as the other. */
5137 if ((lhs == 0 || rhs == 0 || operand_equal_p (lhs, rhs, 0))
5138 && merge_ranges (&in_p, &low, &high, in0_p, low0, high0,
5140 && 0 != (tem = (build_range_check (type,
5142 : rhs != 0 ? rhs : integer_zero_node,
5145 if (strict_overflow_p)
5146 fold_overflow_warning (warnmsg, WARN_STRICT_OVERFLOW_COMPARISON);
5147 return or_op ? invert_truthvalue (tem) : tem;
5150 /* On machines where the branch cost is expensive, if this is a
5151 short-circuited branch and the underlying object on both sides
5152 is the same, make a non-short-circuit operation. */
5153 else if (LOGICAL_OP_NON_SHORT_CIRCUIT
5154 && lhs != 0 && rhs != 0
5155 && (code == TRUTH_ANDIF_EXPR
5156 || code == TRUTH_ORIF_EXPR)
5157 && operand_equal_p (lhs, rhs, 0))
5159 /* If simple enough, just rewrite. Otherwise, make a SAVE_EXPR
5160 unless we are at top level or LHS contains a PLACEHOLDER_EXPR, in
5161 which cases we can't do this. */
5162 if (simple_operand_p (lhs))
5163 return build2 (code == TRUTH_ANDIF_EXPR
5164 ? TRUTH_AND_EXPR : TRUTH_OR_EXPR,
5167 else if (lang_hooks.decls.global_bindings_p () == 0
5168 && ! CONTAINS_PLACEHOLDER_P (lhs))
5170 tree common = save_expr (lhs);
5172 if (0 != (lhs = build_range_check (type, common,
5173 or_op ? ! in0_p : in0_p,
5175 && (0 != (rhs = build_range_check (type, common,
5176 or_op ? ! in1_p : in1_p,
5179 if (strict_overflow_p)
5180 fold_overflow_warning (warnmsg,
5181 WARN_STRICT_OVERFLOW_COMPARISON);
5182 return build2 (code == TRUTH_ANDIF_EXPR
5183 ? TRUTH_AND_EXPR : TRUTH_OR_EXPR,
5192 /* Subroutine for fold_truthop: C is an INTEGER_CST interpreted as a P
5193 bit value. Arrange things so the extra bits will be set to zero if and
5194 only if C is signed-extended to its full width. If MASK is nonzero,
5195 it is an INTEGER_CST that should be AND'ed with the extra bits. */
5198 unextend (tree c, int p, int unsignedp, tree mask)
5200 tree type = TREE_TYPE (c);
5201 int modesize = GET_MODE_BITSIZE (TYPE_MODE (type));
5204 if (p == modesize || unsignedp)
5207 /* We work by getting just the sign bit into the low-order bit, then
5208 into the high-order bit, then sign-extend. We then XOR that value
5210 temp = const_binop (RSHIFT_EXPR, c, size_int (p - 1), 0);
5211 temp = const_binop (BIT_AND_EXPR, temp, size_int (1), 0);
5213 /* We must use a signed type in order to get an arithmetic right shift.
5214 However, we must also avoid introducing accidental overflows, so that
5215 a subsequent call to integer_zerop will work. Hence we must
5216 do the type conversion here. At this point, the constant is either
5217 zero or one, and the conversion to a signed type can never overflow.
5218 We could get an overflow if this conversion is done anywhere else. */
5219 if (TYPE_UNSIGNED (type))
5220 temp = fold_convert (signed_type_for (type), temp);
5222 temp = const_binop (LSHIFT_EXPR, temp, size_int (modesize - 1), 0);
5223 temp = const_binop (RSHIFT_EXPR, temp, size_int (modesize - p - 1), 0);
5225 temp = const_binop (BIT_AND_EXPR, temp,
5226 fold_convert (TREE_TYPE (c), mask), 0);
5227 /* If necessary, convert the type back to match the type of C. */
5228 if (TYPE_UNSIGNED (type))
5229 temp = fold_convert (type, temp);
5231 return fold_convert (type, const_binop (BIT_XOR_EXPR, c, temp, 0));
5234 /* Find ways of folding logical expressions of LHS and RHS:
5235 Try to merge two comparisons to the same innermost item.
5236 Look for range tests like "ch >= '0' && ch <= '9'".
5237 Look for combinations of simple terms on machines with expensive branches
5238 and evaluate the RHS unconditionally.
5240 For example, if we have p->a == 2 && p->b == 4 and we can make an
5241 object large enough to span both A and B, we can do this with a comparison
5242 against the object ANDed with the a mask.
5244 If we have p->a == q->a && p->b == q->b, we may be able to use bit masking
5245 operations to do this with one comparison.
5247 We check for both normal comparisons and the BIT_AND_EXPRs made this by
5248 function and the one above.
5250 CODE is the logical operation being done. It can be TRUTH_ANDIF_EXPR,
5251 TRUTH_AND_EXPR, TRUTH_ORIF_EXPR, or TRUTH_OR_EXPR.
5253 TRUTH_TYPE is the type of the logical operand and LHS and RHS are its
5256 We return the simplified tree or 0 if no optimization is possible. */
5259 fold_truthop (enum tree_code code, tree truth_type, tree lhs, tree rhs)
5261 /* If this is the "or" of two comparisons, we can do something if
5262 the comparisons are NE_EXPR. If this is the "and", we can do something
5263 if the comparisons are EQ_EXPR. I.e.,
5264 (a->b == 2 && a->c == 4) can become (a->new == NEW).
5266 WANTED_CODE is this operation code. For single bit fields, we can
5267 convert EQ_EXPR to NE_EXPR so we need not reject the "wrong"
5268 comparison for one-bit fields. */
5270 enum tree_code wanted_code;
5271 enum tree_code lcode, rcode;
5272 tree ll_arg, lr_arg, rl_arg, rr_arg;
5273 tree ll_inner, lr_inner, rl_inner, rr_inner;
5274 HOST_WIDE_INT ll_bitsize, ll_bitpos, lr_bitsize, lr_bitpos;
5275 HOST_WIDE_INT rl_bitsize, rl_bitpos, rr_bitsize, rr_bitpos;
5276 HOST_WIDE_INT xll_bitpos, xrl_bitpos;
5277 HOST_WIDE_INT lnbitsize, lnbitpos;
5278 int ll_unsignedp, lr_unsignedp, rl_unsignedp, rr_unsignedp;
5279 enum machine_mode ll_mode, lr_mode, rl_mode, rr_mode;
5280 enum machine_mode lnmode;
5281 tree ll_mask, lr_mask, rl_mask, rr_mask;
5282 tree ll_and_mask, lr_and_mask, rl_and_mask, rr_and_mask;
5283 tree l_const, r_const;
5284 tree lntype, result;
5285 int first_bit, end_bit;
5287 tree orig_lhs = lhs, orig_rhs = rhs;
5288 enum tree_code orig_code = code;
5290 /* Start by getting the comparison codes. Fail if anything is volatile.
5291 If one operand is a BIT_AND_EXPR with the constant one, treat it as if
5292 it were surrounded with a NE_EXPR. */
5294 if (TREE_SIDE_EFFECTS (lhs) || TREE_SIDE_EFFECTS (rhs))
5297 lcode = TREE_CODE (lhs);
5298 rcode = TREE_CODE (rhs);
5300 if (lcode == BIT_AND_EXPR && integer_onep (TREE_OPERAND (lhs, 1)))
5302 lhs = build2 (NE_EXPR, truth_type, lhs,
5303 build_int_cst (TREE_TYPE (lhs), 0));
5307 if (rcode == BIT_AND_EXPR && integer_onep (TREE_OPERAND (rhs, 1)))
5309 rhs = build2 (NE_EXPR, truth_type, rhs,
5310 build_int_cst (TREE_TYPE (rhs), 0));
5314 if (TREE_CODE_CLASS (lcode) != tcc_comparison
5315 || TREE_CODE_CLASS (rcode) != tcc_comparison)
5318 ll_arg = TREE_OPERAND (lhs, 0);
5319 lr_arg = TREE_OPERAND (lhs, 1);
5320 rl_arg = TREE_OPERAND (rhs, 0);
5321 rr_arg = TREE_OPERAND (rhs, 1);
5323 /* Simplify (x<y) && (x==y) into (x<=y) and related optimizations. */
5324 if (simple_operand_p (ll_arg)
5325 && simple_operand_p (lr_arg))
5328 if (operand_equal_p (ll_arg, rl_arg, 0)
5329 && operand_equal_p (lr_arg, rr_arg, 0))
5331 result = combine_comparisons (code, lcode, rcode,
5332 truth_type, ll_arg, lr_arg);
5336 else if (operand_equal_p (ll_arg, rr_arg, 0)
5337 && operand_equal_p (lr_arg, rl_arg, 0))
5339 result = combine_comparisons (code, lcode,
5340 swap_tree_comparison (rcode),
5341 truth_type, ll_arg, lr_arg);
5347 code = ((code == TRUTH_AND_EXPR || code == TRUTH_ANDIF_EXPR)
5348 ? TRUTH_AND_EXPR : TRUTH_OR_EXPR);
5350 /* If the RHS can be evaluated unconditionally and its operands are
5351 simple, it wins to evaluate the RHS unconditionally on machines
5352 with expensive branches. In this case, this isn't a comparison
5353 that can be merged. Avoid doing this if the RHS is a floating-point
5354 comparison since those can trap. */
5356 if (BRANCH_COST >= 2
5357 && ! FLOAT_TYPE_P (TREE_TYPE (rl_arg))
5358 && simple_operand_p (rl_arg)
5359 && simple_operand_p (rr_arg))
5361 /* Convert (a != 0) || (b != 0) into (a | b) != 0. */
5362 if (code == TRUTH_OR_EXPR
5363 && lcode == NE_EXPR && integer_zerop (lr_arg)
5364 && rcode == NE_EXPR && integer_zerop (rr_arg)
5365 && TREE_TYPE (ll_arg) == TREE_TYPE (rl_arg)
5366 && INTEGRAL_TYPE_P (TREE_TYPE (ll_arg)))
5367 return build2 (NE_EXPR, truth_type,
5368 build2 (BIT_IOR_EXPR, TREE_TYPE (ll_arg),
5370 build_int_cst (TREE_TYPE (ll_arg), 0));
5372 /* Convert (a == 0) && (b == 0) into (a | b) == 0. */
5373 if (code == TRUTH_AND_EXPR
5374 && lcode == EQ_EXPR && integer_zerop (lr_arg)
5375 && rcode == EQ_EXPR && integer_zerop (rr_arg)
5376 && TREE_TYPE (ll_arg) == TREE_TYPE (rl_arg)
5377 && INTEGRAL_TYPE_P (TREE_TYPE (ll_arg)))
5378 return build2 (EQ_EXPR, truth_type,
5379 build2 (BIT_IOR_EXPR, TREE_TYPE (ll_arg),
5381 build_int_cst (TREE_TYPE (ll_arg), 0));
5383 if (LOGICAL_OP_NON_SHORT_CIRCUIT)
5385 if (code != orig_code || lhs != orig_lhs || rhs != orig_rhs)
5386 return build2 (code, truth_type, lhs, rhs);
5391 /* See if the comparisons can be merged. Then get all the parameters for
5394 if ((lcode != EQ_EXPR && lcode != NE_EXPR)
5395 || (rcode != EQ_EXPR && rcode != NE_EXPR))
5399 ll_inner = decode_field_reference (ll_arg,
5400 &ll_bitsize, &ll_bitpos, &ll_mode,
5401 &ll_unsignedp, &volatilep, &ll_mask,
5403 lr_inner = decode_field_reference (lr_arg,
5404 &lr_bitsize, &lr_bitpos, &lr_mode,
5405 &lr_unsignedp, &volatilep, &lr_mask,
5407 rl_inner = decode_field_reference (rl_arg,
5408 &rl_bitsize, &rl_bitpos, &rl_mode,
5409 &rl_unsignedp, &volatilep, &rl_mask,
5411 rr_inner = decode_field_reference (rr_arg,
5412 &rr_bitsize, &rr_bitpos, &rr_mode,
5413 &rr_unsignedp, &volatilep, &rr_mask,
5416 /* It must be true that the inner operation on the lhs of each
5417 comparison must be the same if we are to be able to do anything.
5418 Then see if we have constants. If not, the same must be true for
5420 if (volatilep || ll_inner == 0 || rl_inner == 0
5421 || ! operand_equal_p (ll_inner, rl_inner, 0))
5424 if (TREE_CODE (lr_arg) == INTEGER_CST
5425 && TREE_CODE (rr_arg) == INTEGER_CST)
5426 l_const = lr_arg, r_const = rr_arg;
5427 else if (lr_inner == 0 || rr_inner == 0
5428 || ! operand_equal_p (lr_inner, rr_inner, 0))
5431 l_const = r_const = 0;
5433 /* If either comparison code is not correct for our logical operation,
5434 fail. However, we can convert a one-bit comparison against zero into
5435 the opposite comparison against that bit being set in the field. */
5437 wanted_code = (code == TRUTH_AND_EXPR ? EQ_EXPR : NE_EXPR);
5438 if (lcode != wanted_code)
5440 if (l_const && integer_zerop (l_const) && integer_pow2p (ll_mask))
5442 /* Make the left operand unsigned, since we are only interested
5443 in the value of one bit. Otherwise we are doing the wrong
5452 /* This is analogous to the code for l_const above. */
5453 if (rcode != wanted_code)
5455 if (r_const && integer_zerop (r_const) && integer_pow2p (rl_mask))
5464 /* See if we can find a mode that contains both fields being compared on
5465 the left. If we can't, fail. Otherwise, update all constants and masks
5466 to be relative to a field of that size. */
5467 first_bit = MIN (ll_bitpos, rl_bitpos);
5468 end_bit = MAX (ll_bitpos + ll_bitsize, rl_bitpos + rl_bitsize);
5469 lnmode = get_best_mode (end_bit - first_bit, first_bit,
5470 TYPE_ALIGN (TREE_TYPE (ll_inner)), word_mode,
5472 if (lnmode == VOIDmode)
5475 lnbitsize = GET_MODE_BITSIZE (lnmode);
5476 lnbitpos = first_bit & ~ (lnbitsize - 1);
5477 lntype = lang_hooks.types.type_for_size (lnbitsize, 1);
5478 xll_bitpos = ll_bitpos - lnbitpos, xrl_bitpos = rl_bitpos - lnbitpos;
5480 if (BYTES_BIG_ENDIAN)
5482 xll_bitpos = lnbitsize - xll_bitpos - ll_bitsize;
5483 xrl_bitpos = lnbitsize - xrl_bitpos - rl_bitsize;
5486 ll_mask = const_binop (LSHIFT_EXPR, fold_convert (lntype, ll_mask),
5487 size_int (xll_bitpos), 0);
5488 rl_mask = const_binop (LSHIFT_EXPR, fold_convert (lntype, rl_mask),
5489 size_int (xrl_bitpos), 0);
5493 l_const = fold_convert (lntype, l_const);
5494 l_const = unextend (l_const, ll_bitsize, ll_unsignedp, ll_and_mask);
5495 l_const = const_binop (LSHIFT_EXPR, l_const, size_int (xll_bitpos), 0);
5496 if (! integer_zerop (const_binop (BIT_AND_EXPR, l_const,
5497 fold_build1 (BIT_NOT_EXPR,
5501 warning (0, "comparison is always %d", wanted_code == NE_EXPR);
5503 return constant_boolean_node (wanted_code == NE_EXPR, truth_type);
5508 r_const = fold_convert (lntype, r_const);
5509 r_const = unextend (r_const, rl_bitsize, rl_unsignedp, rl_and_mask);
5510 r_const = const_binop (LSHIFT_EXPR, r_const, size_int (xrl_bitpos), 0);
5511 if (! integer_zerop (const_binop (BIT_AND_EXPR, r_const,
5512 fold_build1 (BIT_NOT_EXPR,
5516 warning (0, "comparison is always %d", wanted_code == NE_EXPR);
5518 return constant_boolean_node (wanted_code == NE_EXPR, truth_type);
5522 /* Handle the case of comparisons with constants. If there is something in
5523 common between the masks, those bits of the constants must be the same.
5524 If not, the condition is always false. Test for this to avoid generating
5525 incorrect code below. */
5526 result = const_binop (BIT_AND_EXPR, ll_mask, rl_mask, 0);
5527 if (! integer_zerop (result)
5528 && simple_cst_equal (const_binop (BIT_AND_EXPR, result, l_const, 0),
5529 const_binop (BIT_AND_EXPR, result, r_const, 0)) != 1)
5531 if (wanted_code == NE_EXPR)
5533 warning (0, "%<or%> of unmatched not-equal tests is always 1");
5534 return constant_boolean_node (true, truth_type);
5538 warning (0, "%<and%> of mutually exclusive equal-tests is always 0");
5539 return constant_boolean_node (false, truth_type);
5546 /* Optimize T, which is a comparison of a MIN_EXPR or MAX_EXPR with a
5550 optimize_minmax_comparison (enum tree_code code, tree type, tree op0, tree op1)
5553 enum tree_code op_code;
5556 int consts_equal, consts_lt;
5559 STRIP_SIGN_NOPS (arg0);
5561 op_code = TREE_CODE (arg0);
5562 minmax_const = TREE_OPERAND (arg0, 1);
5563 comp_const = fold_convert (TREE_TYPE (arg0), op1);
5564 consts_equal = tree_int_cst_equal (minmax_const, comp_const);
5565 consts_lt = tree_int_cst_lt (minmax_const, comp_const);
5566 inner = TREE_OPERAND (arg0, 0);
5568 /* If something does not permit us to optimize, return the original tree. */
5569 if ((op_code != MIN_EXPR && op_code != MAX_EXPR)
5570 || TREE_CODE (comp_const) != INTEGER_CST
5571 || TREE_OVERFLOW (comp_const)
5572 || TREE_CODE (minmax_const) != INTEGER_CST
5573 || TREE_OVERFLOW (minmax_const))
5576 /* Now handle all the various comparison codes. We only handle EQ_EXPR
5577 and GT_EXPR, doing the rest with recursive calls using logical
5581 case NE_EXPR: case LT_EXPR: case LE_EXPR:
5583 tree tem = optimize_minmax_comparison (invert_tree_comparison (code, false),
5586 return invert_truthvalue (tem);
5592 fold_build2 (TRUTH_ORIF_EXPR, type,
5593 optimize_minmax_comparison
5594 (EQ_EXPR, type, arg0, comp_const),
5595 optimize_minmax_comparison
5596 (GT_EXPR, type, arg0, comp_const));
5599 if (op_code == MAX_EXPR && consts_equal)
5600 /* MAX (X, 0) == 0 -> X <= 0 */
5601 return fold_build2 (LE_EXPR, type, inner, comp_const);
5603 else if (op_code == MAX_EXPR && consts_lt)
5604 /* MAX (X, 0) == 5 -> X == 5 */
5605 return fold_build2 (EQ_EXPR, type, inner, comp_const);
5607 else if (op_code == MAX_EXPR)
5608 /* MAX (X, 0) == -1 -> false */
5609 return omit_one_operand (type, integer_zero_node, inner);
5611 else if (consts_equal)
5612 /* MIN (X, 0) == 0 -> X >= 0 */
5613 return fold_build2 (GE_EXPR, type, inner, comp_const);
5616 /* MIN (X, 0) == 5 -> false */
5617 return omit_one_operand (type, integer_zero_node, inner);
5620 /* MIN (X, 0) == -1 -> X == -1 */
5621 return fold_build2 (EQ_EXPR, type, inner, comp_const);
5624 if (op_code == MAX_EXPR && (consts_equal || consts_lt))
5625 /* MAX (X, 0) > 0 -> X > 0
5626 MAX (X, 0) > 5 -> X > 5 */
5627 return fold_build2 (GT_EXPR, type, inner, comp_const);
5629 else if (op_code == MAX_EXPR)
5630 /* MAX (X, 0) > -1 -> true */
5631 return omit_one_operand (type, integer_one_node, inner);
5633 else if (op_code == MIN_EXPR && (consts_equal || consts_lt))
5634 /* MIN (X, 0) > 0 -> false
5635 MIN (X, 0) > 5 -> false */
5636 return omit_one_operand (type, integer_zero_node, inner);
5639 /* MIN (X, 0) > -1 -> X > -1 */
5640 return fold_build2 (GT_EXPR, type, inner, comp_const);
5647 /* T is an integer expression that is being multiplied, divided, or taken a
5648 modulus (CODE says which and what kind of divide or modulus) by a
5649 constant C. See if we can eliminate that operation by folding it with
5650 other operations already in T. WIDE_TYPE, if non-null, is a type that
5651 should be used for the computation if wider than our type.
5653 For example, if we are dividing (X * 8) + (Y * 16) by 4, we can return
5654 (X * 2) + (Y * 4). We must, however, be assured that either the original
5655 expression would not overflow or that overflow is undefined for the type
5656 in the language in question.
5658 We also canonicalize (X + 7) * 4 into X * 4 + 28 in the hope that either
5659 the machine has a multiply-accumulate insn or that this is part of an
5660 addressing calculation.
5662 If we return a non-null expression, it is an equivalent form of the
5663 original computation, but need not be in the original type.
5665 We set *STRICT_OVERFLOW_P to true if the return values depends on
5666 signed overflow being undefined. Otherwise we do not change
5667 *STRICT_OVERFLOW_P. */
5670 extract_muldiv (tree t, tree c, enum tree_code code, tree wide_type,
5671 bool *strict_overflow_p)
5673 /* To avoid exponential search depth, refuse to allow recursion past
5674 three levels. Beyond that (1) it's highly unlikely that we'll find
5675 something interesting and (2) we've probably processed it before
5676 when we built the inner expression. */
5685 ret = extract_muldiv_1 (t, c, code, wide_type, strict_overflow_p);
5692 extract_muldiv_1 (tree t, tree c, enum tree_code code, tree wide_type,
5693 bool *strict_overflow_p)
5695 tree type = TREE_TYPE (t);
5696 enum tree_code tcode = TREE_CODE (t);
5697 tree ctype = (wide_type != 0 && (GET_MODE_SIZE (TYPE_MODE (wide_type))
5698 > GET_MODE_SIZE (TYPE_MODE (type)))
5699 ? wide_type : type);
5701 int same_p = tcode == code;
5702 tree op0 = NULL_TREE, op1 = NULL_TREE;
5703 bool sub_strict_overflow_p;
5705 /* Don't deal with constants of zero here; they confuse the code below. */
5706 if (integer_zerop (c))
5709 if (TREE_CODE_CLASS (tcode) == tcc_unary)
5710 op0 = TREE_OPERAND (t, 0);
5712 if (TREE_CODE_CLASS (tcode) == tcc_binary)
5713 op0 = TREE_OPERAND (t, 0), op1 = TREE_OPERAND (t, 1);
5715 /* Note that we need not handle conditional operations here since fold
5716 already handles those cases. So just do arithmetic here. */
5720 /* For a constant, we can always simplify if we are a multiply
5721 or (for divide and modulus) if it is a multiple of our constant. */
5722 if (code == MULT_EXPR
5723 || integer_zerop (const_binop (TRUNC_MOD_EXPR, t, c, 0)))
5724 return const_binop (code, fold_convert (ctype, t),
5725 fold_convert (ctype, c), 0);
5728 case CONVERT_EXPR: case NON_LVALUE_EXPR: case NOP_EXPR:
5729 /* If op0 is an expression ... */
5730 if ((COMPARISON_CLASS_P (op0)
5731 || UNARY_CLASS_P (op0)
5732 || BINARY_CLASS_P (op0)
5733 || VL_EXP_CLASS_P (op0)
5734 || EXPRESSION_CLASS_P (op0))
5735 /* ... and is unsigned, and its type is smaller than ctype,
5736 then we cannot pass through as widening. */
5737 && ((TYPE_UNSIGNED (TREE_TYPE (op0))
5738 && ! (TREE_CODE (TREE_TYPE (op0)) == INTEGER_TYPE
5739 && TYPE_IS_SIZETYPE (TREE_TYPE (op0)))
5740 && (GET_MODE_SIZE (TYPE_MODE (ctype))
5741 > GET_MODE_SIZE (TYPE_MODE (TREE_TYPE (op0)))))
5742 /* ... or this is a truncation (t is narrower than op0),
5743 then we cannot pass through this narrowing. */
5744 || (GET_MODE_SIZE (TYPE_MODE (type))
5745 < GET_MODE_SIZE (TYPE_MODE (TREE_TYPE (op0))))
5746 /* ... or signedness changes for division or modulus,
5747 then we cannot pass through this conversion. */
5748 || (code != MULT_EXPR
5749 && (TYPE_UNSIGNED (ctype)
5750 != TYPE_UNSIGNED (TREE_TYPE (op0))))
5751 /* ... or has undefined overflow while the converted to
5752 type has not, we cannot do the operation in the inner type
5753 as that would introduce undefined overflow. */
5754 || (TYPE_OVERFLOW_UNDEFINED (TREE_TYPE (op0))
5755 && !TYPE_OVERFLOW_UNDEFINED (type))))
5758 /* Pass the constant down and see if we can make a simplification. If
5759 we can, replace this expression with the inner simplification for
5760 possible later conversion to our or some other type. */
5761 if ((t2 = fold_convert (TREE_TYPE (op0), c)) != 0
5762 && TREE_CODE (t2) == INTEGER_CST
5763 && !TREE_OVERFLOW (t2)
5764 && (0 != (t1 = extract_muldiv (op0, t2, code,
5766 ? ctype : NULL_TREE,
5767 strict_overflow_p))))
5772 /* If widening the type changes it from signed to unsigned, then we
5773 must avoid building ABS_EXPR itself as unsigned. */
5774 if (TYPE_UNSIGNED (ctype) && !TYPE_UNSIGNED (type))
5776 tree cstype = (*signed_type_for) (ctype);
5777 if ((t1 = extract_muldiv (op0, c, code, cstype, strict_overflow_p))
5780 t1 = fold_build1 (tcode, cstype, fold_convert (cstype, t1));
5781 return fold_convert (ctype, t1);
5785 /* If the constant is negative, we cannot simplify this. */
5786 if (tree_int_cst_sgn (c) == -1)
5790 if ((t1 = extract_muldiv (op0, c, code, wide_type, strict_overflow_p))
5792 return fold_build1 (tcode, ctype, fold_convert (ctype, t1));
5795 case MIN_EXPR: case MAX_EXPR:
5796 /* If widening the type changes the signedness, then we can't perform
5797 this optimization as that changes the result. */
5798 if (TYPE_UNSIGNED (ctype) != TYPE_UNSIGNED (type))
5801 /* MIN (a, b) / 5 -> MIN (a / 5, b / 5) */
5802 sub_strict_overflow_p = false;
5803 if ((t1 = extract_muldiv (op0, c, code, wide_type,
5804 &sub_strict_overflow_p)) != 0
5805 && (t2 = extract_muldiv (op1, c, code, wide_type,
5806 &sub_strict_overflow_p)) != 0)
5808 if (tree_int_cst_sgn (c) < 0)
5809 tcode = (tcode == MIN_EXPR ? MAX_EXPR : MIN_EXPR);
5810 if (sub_strict_overflow_p)
5811 *strict_overflow_p = true;
5812 return fold_build2 (tcode, ctype, fold_convert (ctype, t1),
5813 fold_convert (ctype, t2));
5817 case LSHIFT_EXPR: case RSHIFT_EXPR:
5818 /* If the second operand is constant, this is a multiplication
5819 or floor division, by a power of two, so we can treat it that
5820 way unless the multiplier or divisor overflows. Signed
5821 left-shift overflow is implementation-defined rather than
5822 undefined in C90, so do not convert signed left shift into
5824 if (TREE_CODE (op1) == INTEGER_CST
5825 && (tcode == RSHIFT_EXPR || TYPE_UNSIGNED (TREE_TYPE (op0)))
5826 /* const_binop may not detect overflow correctly,
5827 so check for it explicitly here. */
5828 && TYPE_PRECISION (TREE_TYPE (size_one_node)) > TREE_INT_CST_LOW (op1)
5829 && TREE_INT_CST_HIGH (op1) == 0
5830 && 0 != (t1 = fold_convert (ctype,
5831 const_binop (LSHIFT_EXPR,
5834 && !TREE_OVERFLOW (t1))
5835 return extract_muldiv (build2 (tcode == LSHIFT_EXPR
5836 ? MULT_EXPR : FLOOR_DIV_EXPR,
5837 ctype, fold_convert (ctype, op0), t1),
5838 c, code, wide_type, strict_overflow_p);
5841 case PLUS_EXPR: case MINUS_EXPR:
5842 /* See if we can eliminate the operation on both sides. If we can, we
5843 can return a new PLUS or MINUS. If we can't, the only remaining
5844 cases where we can do anything are if the second operand is a
5846 sub_strict_overflow_p = false;
5847 t1 = extract_muldiv (op0, c, code, wide_type, &sub_strict_overflow_p);
5848 t2 = extract_muldiv (op1, c, code, wide_type, &sub_strict_overflow_p);
5849 if (t1 != 0 && t2 != 0
5850 && (code == MULT_EXPR
5851 /* If not multiplication, we can only do this if both operands
5852 are divisible by c. */
5853 || (multiple_of_p (ctype, op0, c)
5854 && multiple_of_p (ctype, op1, c))))
5856 if (sub_strict_overflow_p)
5857 *strict_overflow_p = true;
5858 return fold_build2 (tcode, ctype, fold_convert (ctype, t1),
5859 fold_convert (ctype, t2));
5862 /* If this was a subtraction, negate OP1 and set it to be an addition.
5863 This simplifies the logic below. */
5864 if (tcode == MINUS_EXPR)
5865 tcode = PLUS_EXPR, op1 = negate_expr (op1);
5867 if (TREE_CODE (op1) != INTEGER_CST)
5870 /* If either OP1 or C are negative, this optimization is not safe for
5871 some of the division and remainder types while for others we need
5872 to change the code. */
5873 if (tree_int_cst_sgn (op1) < 0 || tree_int_cst_sgn (c) < 0)
5875 if (code == CEIL_DIV_EXPR)
5876 code = FLOOR_DIV_EXPR;
5877 else if (code == FLOOR_DIV_EXPR)
5878 code = CEIL_DIV_EXPR;
5879 else if (code != MULT_EXPR
5880 && code != CEIL_MOD_EXPR && code != FLOOR_MOD_EXPR)
5884 /* If it's a multiply or a division/modulus operation of a multiple
5885 of our constant, do the operation and verify it doesn't overflow. */
5886 if (code == MULT_EXPR
5887 || integer_zerop (const_binop (TRUNC_MOD_EXPR, op1, c, 0)))
5889 op1 = const_binop (code, fold_convert (ctype, op1),
5890 fold_convert (ctype, c), 0);
5891 /* We allow the constant to overflow with wrapping semantics. */
5893 || (TREE_OVERFLOW (op1) && !TYPE_OVERFLOW_WRAPS (ctype)))
5899 /* If we have an unsigned type is not a sizetype, we cannot widen
5900 the operation since it will change the result if the original
5901 computation overflowed. */
5902 if (TYPE_UNSIGNED (ctype)
5903 && ! (TREE_CODE (ctype) == INTEGER_TYPE && TYPE_IS_SIZETYPE (ctype))
5907 /* If we were able to eliminate our operation from the first side,
5908 apply our operation to the second side and reform the PLUS. */
5909 if (t1 != 0 && (TREE_CODE (t1) != code || code == MULT_EXPR))
5910 return fold_build2 (tcode, ctype, fold_convert (ctype, t1), op1);
5912 /* The last case is if we are a multiply. In that case, we can
5913 apply the distributive law to commute the multiply and addition
5914 if the multiplication of the constants doesn't overflow. */
5915 if (code == MULT_EXPR)
5916 return fold_build2 (tcode, ctype,
5917 fold_build2 (code, ctype,
5918 fold_convert (ctype, op0),
5919 fold_convert (ctype, c)),
5925 /* We have a special case here if we are doing something like
5926 (C * 8) % 4 since we know that's zero. */
5927 if ((code == TRUNC_MOD_EXPR || code == CEIL_MOD_EXPR
5928 || code == FLOOR_MOD_EXPR || code == ROUND_MOD_EXPR)
5929 && TREE_CODE (TREE_OPERAND (t, 1)) == INTEGER_CST
5930 && integer_zerop (const_binop (TRUNC_MOD_EXPR, op1, c, 0)))
5931 return omit_one_operand (type, integer_zero_node, op0);
5933 /* ... fall through ... */
5935 case TRUNC_DIV_EXPR: case CEIL_DIV_EXPR: case FLOOR_DIV_EXPR:
5936 case ROUND_DIV_EXPR: case EXACT_DIV_EXPR:
5937 /* If we can extract our operation from the LHS, do so and return a
5938 new operation. Likewise for the RHS from a MULT_EXPR. Otherwise,
5939 do something only if the second operand is a constant. */
5941 && (t1 = extract_muldiv (op0, c, code, wide_type,
5942 strict_overflow_p)) != 0)
5943 return fold_build2 (tcode, ctype, fold_convert (ctype, t1),
5944 fold_convert (ctype, op1));
5945 else if (tcode == MULT_EXPR && code == MULT_EXPR
5946 && (t1 = extract_muldiv (op1, c, code, wide_type,
5947 strict_overflow_p)) != 0)
5948 return fold_build2 (tcode, ctype, fold_convert (ctype, op0),
5949 fold_convert (ctype, t1));
5950 else if (TREE_CODE (op1) != INTEGER_CST)
5953 /* If these are the same operation types, we can associate them
5954 assuming no overflow. */
5956 && 0 != (t1 = int_const_binop (MULT_EXPR, fold_convert (ctype, op1),
5957 fold_convert (ctype, c), 1))
5958 && 0 != (t1 = force_fit_type_double (ctype, TREE_INT_CST_LOW (t1),
5959 TREE_INT_CST_HIGH (t1),
5960 (TYPE_UNSIGNED (ctype)
5961 && tcode != MULT_EXPR) ? -1 : 1,
5962 TREE_OVERFLOW (t1)))
5963 && !TREE_OVERFLOW (t1))
5964 return fold_build2 (tcode, ctype, fold_convert (ctype, op0), t1);
5966 /* If these operations "cancel" each other, we have the main
5967 optimizations of this pass, which occur when either constant is a
5968 multiple of the other, in which case we replace this with either an
5969 operation or CODE or TCODE.
5971 If we have an unsigned type that is not a sizetype, we cannot do
5972 this since it will change the result if the original computation
5974 if ((TYPE_OVERFLOW_UNDEFINED (ctype)
5975 || (TREE_CODE (ctype) == INTEGER_TYPE && TYPE_IS_SIZETYPE (ctype)))
5976 && ((code == MULT_EXPR && tcode == EXACT_DIV_EXPR)
5977 || (tcode == MULT_EXPR
5978 && code != TRUNC_MOD_EXPR && code != CEIL_MOD_EXPR
5979 && code != FLOOR_MOD_EXPR && code != ROUND_MOD_EXPR
5980 && code != MULT_EXPR)))
5982 if (integer_zerop (const_binop (TRUNC_MOD_EXPR, op1, c, 0)))
5984 if (TYPE_OVERFLOW_UNDEFINED (ctype))
5985 *strict_overflow_p = true;
5986 return fold_build2 (tcode, ctype, fold_convert (ctype, op0),
5987 fold_convert (ctype,
5988 const_binop (TRUNC_DIV_EXPR,
5991 else if (integer_zerop (const_binop (TRUNC_MOD_EXPR, c, op1, 0)))
5993 if (TYPE_OVERFLOW_UNDEFINED (ctype))
5994 *strict_overflow_p = true;
5995 return fold_build2 (code, ctype, fold_convert (ctype, op0),
5996 fold_convert (ctype,
5997 const_binop (TRUNC_DIV_EXPR,
6010 /* Return a node which has the indicated constant VALUE (either 0 or
6011 1), and is of the indicated TYPE. */
6014 constant_boolean_node (int value, tree type)
6016 if (type == integer_type_node)
6017 return value ? integer_one_node : integer_zero_node;
6018 else if (type == boolean_type_node)
6019 return value ? boolean_true_node : boolean_false_node;
6021 return build_int_cst (type, value);
6025 /* Transform `a + (b ? x : y)' into `b ? (a + x) : (a + y)'.
6026 Transform, `a + (x < y)' into `(x < y) ? (a + 1) : (a + 0)'. Here
6027 CODE corresponds to the `+', COND to the `(b ? x : y)' or `(x < y)'
6028 expression, and ARG to `a'. If COND_FIRST_P is nonzero, then the
6029 COND is the first argument to CODE; otherwise (as in the example
6030 given here), it is the second argument. TYPE is the type of the
6031 original expression. Return NULL_TREE if no simplification is
6035 fold_binary_op_with_conditional_arg (enum tree_code code,
6036 tree type, tree op0, tree op1,
6037 tree cond, tree arg, int cond_first_p)
6039 tree cond_type = cond_first_p ? TREE_TYPE (op0) : TREE_TYPE (op1);
6040 tree arg_type = cond_first_p ? TREE_TYPE (op1) : TREE_TYPE (op0);
6041 tree test, true_value, false_value;
6042 tree lhs = NULL_TREE;
6043 tree rhs = NULL_TREE;
6045 /* This transformation is only worthwhile if we don't have to wrap
6046 arg in a SAVE_EXPR, and the operation can be simplified on at least
6047 one of the branches once its pushed inside the COND_EXPR. */
6048 if (!TREE_CONSTANT (arg))
6051 if (TREE_CODE (cond) == COND_EXPR)
6053 test = TREE_OPERAND (cond, 0);
6054 true_value = TREE_OPERAND (cond, 1);
6055 false_value = TREE_OPERAND (cond, 2);
6056 /* If this operand throws an expression, then it does not make
6057 sense to try to perform a logical or arithmetic operation
6059 if (VOID_TYPE_P (TREE_TYPE (true_value)))
6061 if (VOID_TYPE_P (TREE_TYPE (false_value)))
6066 tree testtype = TREE_TYPE (cond);
6068 true_value = constant_boolean_node (true, testtype);
6069 false_value = constant_boolean_node (false, testtype);
6072 arg = fold_convert (arg_type, arg);
6075 true_value = fold_convert (cond_type, true_value);
6077 lhs = fold_build2 (code, type, true_value, arg);
6079 lhs = fold_build2 (code, type, arg, true_value);
6083 false_value = fold_convert (cond_type, false_value);
6085 rhs = fold_build2 (code, type, false_value, arg);
6087 rhs = fold_build2 (code, type, arg, false_value);
6090 test = fold_build3 (COND_EXPR, type, test, lhs, rhs);
6091 return fold_convert (type, test);
6095 /* Subroutine of fold() that checks for the addition of +/- 0.0.
6097 If !NEGATE, return true if ADDEND is +/-0.0 and, for all X of type
6098 TYPE, X + ADDEND is the same as X. If NEGATE, return true if X -
6099 ADDEND is the same as X.
6101 X + 0 and X - 0 both give X when X is NaN, infinite, or nonzero
6102 and finite. The problematic cases are when X is zero, and its mode
6103 has signed zeros. In the case of rounding towards -infinity,
6104 X - 0 is not the same as X because 0 - 0 is -0. In other rounding
6105 modes, X + 0 is not the same as X because -0 + 0 is 0. */
6108 fold_real_zero_addition_p (const_tree type, const_tree addend, int negate)
6110 if (!real_zerop (addend))
6113 /* Don't allow the fold with -fsignaling-nans. */
6114 if (HONOR_SNANS (TYPE_MODE (type)))
6117 /* Allow the fold if zeros aren't signed, or their sign isn't important. */
6118 if (!HONOR_SIGNED_ZEROS (TYPE_MODE (type)))
6121 /* Treat x + -0 as x - 0 and x - -0 as x + 0. */
6122 if (TREE_CODE (addend) == REAL_CST
6123 && REAL_VALUE_MINUS_ZERO (TREE_REAL_CST (addend)))
6126 /* The mode has signed zeros, and we have to honor their sign.
6127 In this situation, there is only one case we can return true for.
6128 X - 0 is the same as X unless rounding towards -infinity is
6130 return negate && !HONOR_SIGN_DEPENDENT_ROUNDING (TYPE_MODE (type));
6133 /* Subroutine of fold() that checks comparisons of built-in math
6134 functions against real constants.
6136 FCODE is the DECL_FUNCTION_CODE of the built-in, CODE is the comparison
6137 operator: EQ_EXPR, NE_EXPR, GT_EXPR, LT_EXPR, GE_EXPR or LE_EXPR. TYPE
6138 is the type of the result and ARG0 and ARG1 are the operands of the
6139 comparison. ARG1 must be a TREE_REAL_CST.
6141 The function returns the constant folded tree if a simplification
6142 can be made, and NULL_TREE otherwise. */
6145 fold_mathfn_compare (enum built_in_function fcode, enum tree_code code,
6146 tree type, tree arg0, tree arg1)
6150 if (BUILTIN_SQRT_P (fcode))
6152 tree arg = CALL_EXPR_ARG (arg0, 0);
6153 enum machine_mode mode = TYPE_MODE (TREE_TYPE (arg0));
6155 c = TREE_REAL_CST (arg1);
6156 if (REAL_VALUE_NEGATIVE (c))
6158 /* sqrt(x) < y is always false, if y is negative. */
6159 if (code == EQ_EXPR || code == LT_EXPR || code == LE_EXPR)
6160 return omit_one_operand (type, integer_zero_node, arg);
6162 /* sqrt(x) > y is always true, if y is negative and we
6163 don't care about NaNs, i.e. negative values of x. */
6164 if (code == NE_EXPR || !HONOR_NANS (mode))
6165 return omit_one_operand (type, integer_one_node, arg);
6167 /* sqrt(x) > y is the same as x >= 0, if y is negative. */
6168 return fold_build2 (GE_EXPR, type, arg,
6169 build_real (TREE_TYPE (arg), dconst0));
6171 else if (code == GT_EXPR || code == GE_EXPR)
6175 REAL_ARITHMETIC (c2, MULT_EXPR, c, c);
6176 real_convert (&c2, mode, &c2);
6178 if (REAL_VALUE_ISINF (c2))
6180 /* sqrt(x) > y is x == +Inf, when y is very large. */
6181 if (HONOR_INFINITIES (mode))
6182 return fold_build2 (EQ_EXPR, type, arg,
6183 build_real (TREE_TYPE (arg), c2));
6185 /* sqrt(x) > y is always false, when y is very large
6186 and we don't care about infinities. */
6187 return omit_one_operand (type, integer_zero_node, arg);
6190 /* sqrt(x) > c is the same as x > c*c. */
6191 return fold_build2 (code, type, arg,
6192 build_real (TREE_TYPE (arg), c2));
6194 else if (code == LT_EXPR || code == LE_EXPR)
6198 REAL_ARITHMETIC (c2, MULT_EXPR, c, c);
6199 real_convert (&c2, mode, &c2);
6201 if (REAL_VALUE_ISINF (c2))
6203 /* sqrt(x) < y is always true, when y is a very large
6204 value and we don't care about NaNs or Infinities. */
6205 if (! HONOR_NANS (mode) && ! HONOR_INFINITIES (mode))
6206 return omit_one_operand (type, integer_one_node, arg);
6208 /* sqrt(x) < y is x != +Inf when y is very large and we
6209 don't care about NaNs. */
6210 if (! HONOR_NANS (mode))
6211 return fold_build2 (NE_EXPR, type, arg,
6212 build_real (TREE_TYPE (arg), c2));
6214 /* sqrt(x) < y is x >= 0 when y is very large and we
6215 don't care about Infinities. */
6216 if (! HONOR_INFINITIES (mode))
6217 return fold_build2 (GE_EXPR, type, arg,
6218 build_real (TREE_TYPE (arg), dconst0));
6220 /* sqrt(x) < y is x >= 0 && x != +Inf, when y is large. */
6221 if (lang_hooks.decls.global_bindings_p () != 0
6222 || CONTAINS_PLACEHOLDER_P (arg))
6225 arg = save_expr (arg);
6226 return fold_build2 (TRUTH_ANDIF_EXPR, type,
6227 fold_build2 (GE_EXPR, type, arg,
6228 build_real (TREE_TYPE (arg),
6230 fold_build2 (NE_EXPR, type, arg,
6231 build_real (TREE_TYPE (arg),
6235 /* sqrt(x) < c is the same as x < c*c, if we ignore NaNs. */
6236 if (! HONOR_NANS (mode))
6237 return fold_build2 (code, type, arg,
6238 build_real (TREE_TYPE (arg), c2));
6240 /* sqrt(x) < c is the same as x >= 0 && x < c*c. */
6241 if (lang_hooks.decls.global_bindings_p () == 0
6242 && ! CONTAINS_PLACEHOLDER_P (arg))
6244 arg = save_expr (arg);
6245 return fold_build2 (TRUTH_ANDIF_EXPR, type,
6246 fold_build2 (GE_EXPR, type, arg,
6247 build_real (TREE_TYPE (arg),
6249 fold_build2 (code, type, arg,
6250 build_real (TREE_TYPE (arg),
6259 /* Subroutine of fold() that optimizes comparisons against Infinities,
6260 either +Inf or -Inf.
6262 CODE is the comparison operator: EQ_EXPR, NE_EXPR, GT_EXPR, LT_EXPR,
6263 GE_EXPR or LE_EXPR. TYPE is the type of the result and ARG0 and ARG1
6264 are the operands of the comparison. ARG1 must be a TREE_REAL_CST.
6266 The function returns the constant folded tree if a simplification
6267 can be made, and NULL_TREE otherwise. */
6270 fold_inf_compare (enum tree_code code, tree type, tree arg0, tree arg1)
6272 enum machine_mode mode;
6273 REAL_VALUE_TYPE max;
6277 mode = TYPE_MODE (TREE_TYPE (arg0));
6279 /* For negative infinity swap the sense of the comparison. */
6280 neg = REAL_VALUE_NEGATIVE (TREE_REAL_CST (arg1));
6282 code = swap_tree_comparison (code);
6287 /* x > +Inf is always false, if with ignore sNANs. */
6288 if (HONOR_SNANS (mode))
6290 return omit_one_operand (type, integer_zero_node, arg0);
6293 /* x <= +Inf is always true, if we don't case about NaNs. */
6294 if (! HONOR_NANS (mode))
6295 return omit_one_operand (type, integer_one_node, arg0);
6297 /* x <= +Inf is the same as x == x, i.e. isfinite(x). */
6298 if (lang_hooks.decls.global_bindings_p () == 0
6299 && ! CONTAINS_PLACEHOLDER_P (arg0))
6301 arg0 = save_expr (arg0);
6302 return fold_build2 (EQ_EXPR, type, arg0, arg0);
6308 /* x == +Inf and x >= +Inf are always equal to x > DBL_MAX. */
6309 real_maxval (&max, neg, mode);
6310 return fold_build2 (neg ? LT_EXPR : GT_EXPR, type,
6311 arg0, build_real (TREE_TYPE (arg0), max));
6314 /* x < +Inf is always equal to x <= DBL_MAX. */
6315 real_maxval (&max, neg, mode);
6316 return fold_build2 (neg ? GE_EXPR : LE_EXPR, type,
6317 arg0, build_real (TREE_TYPE (arg0), max));
6320 /* x != +Inf is always equal to !(x > DBL_MAX). */
6321 real_maxval (&max, neg, mode);
6322 if (! HONOR_NANS (mode))
6323 return fold_build2 (neg ? GE_EXPR : LE_EXPR, type,
6324 arg0, build_real (TREE_TYPE (arg0), max));
6326 temp = fold_build2 (neg ? LT_EXPR : GT_EXPR, type,
6327 arg0, build_real (TREE_TYPE (arg0), max));
6328 return fold_build1 (TRUTH_NOT_EXPR, type, temp);
6337 /* Subroutine of fold() that optimizes comparisons of a division by
6338 a nonzero integer constant against an integer constant, i.e.
6341 CODE is the comparison operator: EQ_EXPR, NE_EXPR, GT_EXPR, LT_EXPR,
6342 GE_EXPR or LE_EXPR. TYPE is the type of the result and ARG0 and ARG1
6343 are the operands of the comparison. ARG1 must be a TREE_REAL_CST.
6345 The function returns the constant folded tree if a simplification
6346 can be made, and NULL_TREE otherwise. */
6349 fold_div_compare (enum tree_code code, tree type, tree arg0, tree arg1)
6351 tree prod, tmp, hi, lo;
6352 tree arg00 = TREE_OPERAND (arg0, 0);
6353 tree arg01 = TREE_OPERAND (arg0, 1);
6354 unsigned HOST_WIDE_INT lpart;
6355 HOST_WIDE_INT hpart;
6356 bool unsigned_p = TYPE_UNSIGNED (TREE_TYPE (arg0));
6360 /* We have to do this the hard way to detect unsigned overflow.
6361 prod = int_const_binop (MULT_EXPR, arg01, arg1, 0); */
6362 overflow = mul_double_with_sign (TREE_INT_CST_LOW (arg01),
6363 TREE_INT_CST_HIGH (arg01),
6364 TREE_INT_CST_LOW (arg1),
6365 TREE_INT_CST_HIGH (arg1),
6366 &lpart, &hpart, unsigned_p);
6367 prod = force_fit_type_double (TREE_TYPE (arg00), lpart, hpart,
6369 neg_overflow = false;
6373 tmp = int_const_binop (MINUS_EXPR, arg01,
6374 build_int_cst (TREE_TYPE (arg01), 1), 0);
6377 /* Likewise hi = int_const_binop (PLUS_EXPR, prod, tmp, 0). */
6378 overflow = add_double_with_sign (TREE_INT_CST_LOW (prod),
6379 TREE_INT_CST_HIGH (prod),
6380 TREE_INT_CST_LOW (tmp),
6381 TREE_INT_CST_HIGH (tmp),
6382 &lpart, &hpart, unsigned_p);
6383 hi = force_fit_type_double (TREE_TYPE (arg00), lpart, hpart,
6384 -1, overflow | TREE_OVERFLOW (prod));
6386 else if (tree_int_cst_sgn (arg01) >= 0)
6388 tmp = int_const_binop (MINUS_EXPR, arg01,
6389 build_int_cst (TREE_TYPE (arg01), 1), 0);
6390 switch (tree_int_cst_sgn (arg1))
6393 neg_overflow = true;
6394 lo = int_const_binop (MINUS_EXPR, prod, tmp, 0);
6399 lo = fold_negate_const (tmp, TREE_TYPE (arg0));
6404 hi = int_const_binop (PLUS_EXPR, prod, tmp, 0);
6414 /* A negative divisor reverses the relational operators. */
6415 code = swap_tree_comparison (code);
6417 tmp = int_const_binop (PLUS_EXPR, arg01,
6418 build_int_cst (TREE_TYPE (arg01), 1), 0);
6419 switch (tree_int_cst_sgn (arg1))
6422 hi = int_const_binop (MINUS_EXPR, prod, tmp, 0);
6427 hi = fold_negate_const (tmp, TREE_TYPE (arg0));
6432 neg_overflow = true;
6433 lo = int_const_binop (PLUS_EXPR, prod, tmp, 0);
6445 if (TREE_OVERFLOW (lo) && TREE_OVERFLOW (hi))
6446 return omit_one_operand (type, integer_zero_node, arg00);
6447 if (TREE_OVERFLOW (hi))
6448 return fold_build2 (GE_EXPR, type, arg00, lo);
6449 if (TREE_OVERFLOW (lo))
6450 return fold_build2 (LE_EXPR, type, arg00, hi);
6451 return build_range_check (type, arg00, 1, lo, hi);
6454 if (TREE_OVERFLOW (lo) && TREE_OVERFLOW (hi))
6455 return omit_one_operand (type, integer_one_node, arg00);
6456 if (TREE_OVERFLOW (hi))
6457 return fold_build2 (LT_EXPR, type, arg00, lo);
6458 if (TREE_OVERFLOW (lo))
6459 return fold_build2 (GT_EXPR, type, arg00, hi);
6460 return build_range_check (type, arg00, 0, lo, hi);
6463 if (TREE_OVERFLOW (lo))
6465 tmp = neg_overflow ? integer_zero_node : integer_one_node;
6466 return omit_one_operand (type, tmp, arg00);
6468 return fold_build2 (LT_EXPR, type, arg00, lo);
6471 if (TREE_OVERFLOW (hi))
6473 tmp = neg_overflow ? integer_zero_node : integer_one_node;
6474 return omit_one_operand (type, tmp, arg00);
6476 return fold_build2 (LE_EXPR, type, arg00, hi);
6479 if (TREE_OVERFLOW (hi))
6481 tmp = neg_overflow ? integer_one_node : integer_zero_node;
6482 return omit_one_operand (type, tmp, arg00);
6484 return fold_build2 (GT_EXPR, type, arg00, hi);
6487 if (TREE_OVERFLOW (lo))
6489 tmp = neg_overflow ? integer_one_node : integer_zero_node;
6490 return omit_one_operand (type, tmp, arg00);
6492 return fold_build2 (GE_EXPR, type, arg00, lo);
6502 /* If CODE with arguments ARG0 and ARG1 represents a single bit
6503 equality/inequality test, then return a simplified form of the test
6504 using a sign testing. Otherwise return NULL. TYPE is the desired
6508 fold_single_bit_test_into_sign_test (enum tree_code code, tree arg0, tree arg1,
6511 /* If this is testing a single bit, we can optimize the test. */
6512 if ((code == NE_EXPR || code == EQ_EXPR)
6513 && TREE_CODE (arg0) == BIT_AND_EXPR && integer_zerop (arg1)
6514 && integer_pow2p (TREE_OPERAND (arg0, 1)))
6516 /* If we have (A & C) != 0 where C is the sign bit of A, convert
6517 this into A < 0. Similarly for (A & C) == 0 into A >= 0. */
6518 tree arg00 = sign_bit_p (TREE_OPERAND (arg0, 0), TREE_OPERAND (arg0, 1));
6520 if (arg00 != NULL_TREE
6521 /* This is only a win if casting to a signed type is cheap,
6522 i.e. when arg00's type is not a partial mode. */
6523 && TYPE_PRECISION (TREE_TYPE (arg00))
6524 == GET_MODE_BITSIZE (TYPE_MODE (TREE_TYPE (arg00))))
6526 tree stype = signed_type_for (TREE_TYPE (arg00));
6527 return fold_build2 (code == EQ_EXPR ? GE_EXPR : LT_EXPR,
6528 result_type, fold_convert (stype, arg00),
6529 build_int_cst (stype, 0));
6536 /* If CODE with arguments ARG0 and ARG1 represents a single bit
6537 equality/inequality test, then return a simplified form of
6538 the test using shifts and logical operations. Otherwise return
6539 NULL. TYPE is the desired result type. */
6542 fold_single_bit_test (enum tree_code code, tree arg0, tree arg1,
6545 /* If this is testing a single bit, we can optimize the test. */
6546 if ((code == NE_EXPR || code == EQ_EXPR)
6547 && TREE_CODE (arg0) == BIT_AND_EXPR && integer_zerop (arg1)
6548 && integer_pow2p (TREE_OPERAND (arg0, 1)))
6550 tree inner = TREE_OPERAND (arg0, 0);
6551 tree type = TREE_TYPE (arg0);
6552 int bitnum = tree_log2 (TREE_OPERAND (arg0, 1));
6553 enum machine_mode operand_mode = TYPE_MODE (type);
6555 tree signed_type, unsigned_type, intermediate_type;
6558 /* First, see if we can fold the single bit test into a sign-bit
6560 tem = fold_single_bit_test_into_sign_test (code, arg0, arg1,
6565 /* Otherwise we have (A & C) != 0 where C is a single bit,
6566 convert that into ((A >> C2) & 1). Where C2 = log2(C).
6567 Similarly for (A & C) == 0. */
6569 /* If INNER is a right shift of a constant and it plus BITNUM does
6570 not overflow, adjust BITNUM and INNER. */
6571 if (TREE_CODE (inner) == RSHIFT_EXPR
6572 && TREE_CODE (TREE_OPERAND (inner, 1)) == INTEGER_CST
6573 && TREE_INT_CST_HIGH (TREE_OPERAND (inner, 1)) == 0
6574 && bitnum < TYPE_PRECISION (type)
6575 && 0 > compare_tree_int (TREE_OPERAND (inner, 1),
6576 bitnum - TYPE_PRECISION (type)))
6578 bitnum += TREE_INT_CST_LOW (TREE_OPERAND (inner, 1));
6579 inner = TREE_OPERAND (inner, 0);
6582 /* If we are going to be able to omit the AND below, we must do our
6583 operations as unsigned. If we must use the AND, we have a choice.
6584 Normally unsigned is faster, but for some machines signed is. */
6585 #ifdef LOAD_EXTEND_OP
6586 ops_unsigned = (LOAD_EXTEND_OP (operand_mode) == SIGN_EXTEND
6587 && !flag_syntax_only) ? 0 : 1;
6592 signed_type = lang_hooks.types.type_for_mode (operand_mode, 0);
6593 unsigned_type = lang_hooks.types.type_for_mode (operand_mode, 1);
6594 intermediate_type = ops_unsigned ? unsigned_type : signed_type;
6595 inner = fold_convert (intermediate_type, inner);
6598 inner = build2 (RSHIFT_EXPR, intermediate_type,
6599 inner, size_int (bitnum));
6601 one = build_int_cst (intermediate_type, 1);
6603 if (code == EQ_EXPR)
6604 inner = fold_build2 (BIT_XOR_EXPR, intermediate_type, inner, one);
6606 /* Put the AND last so it can combine with more things. */
6607 inner = build2 (BIT_AND_EXPR, intermediate_type, inner, one);
6609 /* Make sure to return the proper type. */
6610 inner = fold_convert (result_type, inner);
6617 /* Check whether we are allowed to reorder operands arg0 and arg1,
6618 such that the evaluation of arg1 occurs before arg0. */
6621 reorder_operands_p (const_tree arg0, const_tree arg1)
6623 if (! flag_evaluation_order)
6625 if (TREE_CONSTANT (arg0) || TREE_CONSTANT (arg1))
6627 return ! TREE_SIDE_EFFECTS (arg0)
6628 && ! TREE_SIDE_EFFECTS (arg1);
6631 /* Test whether it is preferable two swap two operands, ARG0 and
6632 ARG1, for example because ARG0 is an integer constant and ARG1
6633 isn't. If REORDER is true, only recommend swapping if we can
6634 evaluate the operands in reverse order. */
6637 tree_swap_operands_p (const_tree arg0, const_tree arg1, bool reorder)
6639 STRIP_SIGN_NOPS (arg0);
6640 STRIP_SIGN_NOPS (arg1);
6642 if (TREE_CODE (arg1) == INTEGER_CST)
6644 if (TREE_CODE (arg0) == INTEGER_CST)
6647 if (TREE_CODE (arg1) == REAL_CST)
6649 if (TREE_CODE (arg0) == REAL_CST)
6652 if (TREE_CODE (arg1) == FIXED_CST)
6654 if (TREE_CODE (arg0) == FIXED_CST)
6657 if (TREE_CODE (arg1) == COMPLEX_CST)
6659 if (TREE_CODE (arg0) == COMPLEX_CST)
6662 if (TREE_CONSTANT (arg1))
6664 if (TREE_CONSTANT (arg0))
6670 if (reorder && flag_evaluation_order
6671 && (TREE_SIDE_EFFECTS (arg0) || TREE_SIDE_EFFECTS (arg1)))
6674 /* It is preferable to swap two SSA_NAME to ensure a canonical form
6675 for commutative and comparison operators. Ensuring a canonical
6676 form allows the optimizers to find additional redundancies without
6677 having to explicitly check for both orderings. */
6678 if (TREE_CODE (arg0) == SSA_NAME
6679 && TREE_CODE (arg1) == SSA_NAME
6680 && SSA_NAME_VERSION (arg0) > SSA_NAME_VERSION (arg1))
6683 /* Put SSA_NAMEs last. */
6684 if (TREE_CODE (arg1) == SSA_NAME)
6686 if (TREE_CODE (arg0) == SSA_NAME)
6689 /* Put variables last. */
6698 /* Fold comparison ARG0 CODE ARG1 (with result in TYPE), where
6699 ARG0 is extended to a wider type. */
6702 fold_widened_comparison (enum tree_code code, tree type, tree arg0, tree arg1)
6704 tree arg0_unw = get_unwidened (arg0, NULL_TREE);
6706 tree shorter_type, outer_type;
6710 if (arg0_unw == arg0)
6712 shorter_type = TREE_TYPE (arg0_unw);
6714 #ifdef HAVE_canonicalize_funcptr_for_compare
6715 /* Disable this optimization if we're casting a function pointer
6716 type on targets that require function pointer canonicalization. */
6717 if (HAVE_canonicalize_funcptr_for_compare
6718 && TREE_CODE (shorter_type) == POINTER_TYPE
6719 && TREE_CODE (TREE_TYPE (shorter_type)) == FUNCTION_TYPE)
6723 if (TYPE_PRECISION (TREE_TYPE (arg0)) <= TYPE_PRECISION (shorter_type))
6726 arg1_unw = get_unwidened (arg1, NULL_TREE);
6728 /* If possible, express the comparison in the shorter mode. */
6729 if ((code == EQ_EXPR || code == NE_EXPR
6730 || TYPE_UNSIGNED (TREE_TYPE (arg0)) == TYPE_UNSIGNED (shorter_type))
6731 && (TREE_TYPE (arg1_unw) == shorter_type
6732 || (TYPE_PRECISION (shorter_type)
6733 > TYPE_PRECISION (TREE_TYPE (arg1_unw)))
6734 || ((TYPE_PRECISION (shorter_type)
6735 == TYPE_PRECISION (TREE_TYPE (arg1_unw)))
6736 && (TYPE_UNSIGNED (shorter_type)
6737 == TYPE_UNSIGNED (TREE_TYPE (arg1_unw))))
6738 || (TREE_CODE (arg1_unw) == INTEGER_CST
6739 && (TREE_CODE (shorter_type) == INTEGER_TYPE
6740 || TREE_CODE (shorter_type) == BOOLEAN_TYPE)
6741 && int_fits_type_p (arg1_unw, shorter_type))))
6742 return fold_build2 (code, type, arg0_unw,
6743 fold_convert (shorter_type, arg1_unw));
6745 if (TREE_CODE (arg1_unw) != INTEGER_CST
6746 || TREE_CODE (shorter_type) != INTEGER_TYPE
6747 || !int_fits_type_p (arg1_unw, shorter_type))
6750 /* If we are comparing with the integer that does not fit into the range
6751 of the shorter type, the result is known. */
6752 outer_type = TREE_TYPE (arg1_unw);
6753 min = lower_bound_in_type (outer_type, shorter_type);
6754 max = upper_bound_in_type (outer_type, shorter_type);
6756 above = integer_nonzerop (fold_relational_const (LT_EXPR, type,
6758 below = integer_nonzerop (fold_relational_const (LT_EXPR, type,
6765 return omit_one_operand (type, integer_zero_node, arg0);
6770 return omit_one_operand (type, integer_one_node, arg0);
6776 return omit_one_operand (type, integer_one_node, arg0);
6778 return omit_one_operand (type, integer_zero_node, arg0);
6783 return omit_one_operand (type, integer_zero_node, arg0);
6785 return omit_one_operand (type, integer_one_node, arg0);
6794 /* Fold comparison ARG0 CODE ARG1 (with result in TYPE), where for
6795 ARG0 just the signedness is changed. */
6798 fold_sign_changed_comparison (enum tree_code code, tree type,
6799 tree arg0, tree arg1)
6802 tree inner_type, outer_type;
6804 if (TREE_CODE (arg0) != NOP_EXPR
6805 && TREE_CODE (arg0) != CONVERT_EXPR)
6808 outer_type = TREE_TYPE (arg0);
6809 arg0_inner = TREE_OPERAND (arg0, 0);
6810 inner_type = TREE_TYPE (arg0_inner);
6812 #ifdef HAVE_canonicalize_funcptr_for_compare
6813 /* Disable this optimization if we're casting a function pointer
6814 type on targets that require function pointer canonicalization. */
6815 if (HAVE_canonicalize_funcptr_for_compare
6816 && TREE_CODE (inner_type) == POINTER_TYPE
6817 && TREE_CODE (TREE_TYPE (inner_type)) == FUNCTION_TYPE)
6821 if (TYPE_PRECISION (inner_type) != TYPE_PRECISION (outer_type))
6824 /* If the conversion is from an integral subtype to its basetype
6826 if (TREE_TYPE (inner_type) == outer_type)
6829 if (TREE_CODE (arg1) != INTEGER_CST
6830 && !((TREE_CODE (arg1) == NOP_EXPR
6831 || TREE_CODE (arg1) == CONVERT_EXPR)
6832 && TREE_TYPE (TREE_OPERAND (arg1, 0)) == inner_type))
6835 if (TYPE_UNSIGNED (inner_type) != TYPE_UNSIGNED (outer_type)
6840 if (TREE_CODE (arg1) == INTEGER_CST)
6841 arg1 = force_fit_type_double (inner_type, TREE_INT_CST_LOW (arg1),
6842 TREE_INT_CST_HIGH (arg1), 0,
6843 TREE_OVERFLOW (arg1));
6845 arg1 = fold_convert (inner_type, arg1);
6847 return fold_build2 (code, type, arg0_inner, arg1);
6850 /* Tries to replace &a[idx] p+ s * delta with &a[idx + delta], if s is
6851 step of the array. Reconstructs s and delta in the case of s * delta
6852 being an integer constant (and thus already folded).
6853 ADDR is the address. MULT is the multiplicative expression.
6854 If the function succeeds, the new address expression is returned. Otherwise
6855 NULL_TREE is returned. */
6858 try_move_mult_to_index (tree addr, tree op1)
6860 tree s, delta, step;
6861 tree ref = TREE_OPERAND (addr, 0), pref;
6866 /* Strip the nops that might be added when converting op1 to sizetype. */
6869 /* Canonicalize op1 into a possibly non-constant delta
6870 and an INTEGER_CST s. */
6871 if (TREE_CODE (op1) == MULT_EXPR)
6873 tree arg0 = TREE_OPERAND (op1, 0), arg1 = TREE_OPERAND (op1, 1);
6878 if (TREE_CODE (arg0) == INTEGER_CST)
6883 else if (TREE_CODE (arg1) == INTEGER_CST)
6891 else if (TREE_CODE (op1) == INTEGER_CST)
6898 /* Simulate we are delta * 1. */
6900 s = integer_one_node;
6903 for (;; ref = TREE_OPERAND (ref, 0))
6905 if (TREE_CODE (ref) == ARRAY_REF)
6907 /* Remember if this was a multi-dimensional array. */
6908 if (TREE_CODE (TREE_OPERAND (ref, 0)) == ARRAY_REF)
6911 itype = TYPE_DOMAIN (TREE_TYPE (TREE_OPERAND (ref, 0)));
6915 step = array_ref_element_size (ref);
6916 if (TREE_CODE (step) != INTEGER_CST)
6921 if (! tree_int_cst_equal (step, s))
6926 /* Try if delta is a multiple of step. */
6927 tree tmp = div_if_zero_remainder (EXACT_DIV_EXPR, op1, step);
6933 /* Only fold here if we can verify we do not overflow one
6934 dimension of a multi-dimensional array. */
6939 if (TREE_CODE (TREE_OPERAND (ref, 1)) != INTEGER_CST
6940 || !INTEGRAL_TYPE_P (itype)
6941 || !TYPE_MAX_VALUE (itype)
6942 || TREE_CODE (TYPE_MAX_VALUE (itype)) != INTEGER_CST)
6945 tmp = fold_binary (PLUS_EXPR, itype,
6946 fold_convert (itype,
6947 TREE_OPERAND (ref, 1)),
6948 fold_convert (itype, delta));
6950 || TREE_CODE (tmp) != INTEGER_CST
6951 || tree_int_cst_lt (TYPE_MAX_VALUE (itype), tmp))
6960 if (!handled_component_p (ref))
6964 /* We found the suitable array reference. So copy everything up to it,
6965 and replace the index. */
6967 pref = TREE_OPERAND (addr, 0);
6968 ret = copy_node (pref);
6973 pref = TREE_OPERAND (pref, 0);
6974 TREE_OPERAND (pos, 0) = copy_node (pref);
6975 pos = TREE_OPERAND (pos, 0);
6978 TREE_OPERAND (pos, 1) = fold_build2 (PLUS_EXPR, itype,
6979 fold_convert (itype,
6980 TREE_OPERAND (pos, 1)),
6981 fold_convert (itype, delta));
6983 return fold_build1 (ADDR_EXPR, TREE_TYPE (addr), ret);
6987 /* Fold A < X && A + 1 > Y to A < X && A >= Y. Normally A + 1 > Y
6988 means A >= Y && A != MAX, but in this case we know that
6989 A < X <= MAX. INEQ is A + 1 > Y, BOUND is A < X. */
6992 fold_to_nonsharp_ineq_using_bound (tree ineq, tree bound)
6994 tree a, typea, type = TREE_TYPE (ineq), a1, diff, y;
6996 if (TREE_CODE (bound) == LT_EXPR)
6997 a = TREE_OPERAND (bound, 0);
6998 else if (TREE_CODE (bound) == GT_EXPR)
6999 a = TREE_OPERAND (bound, 1);
7003 typea = TREE_TYPE (a);
7004 if (!INTEGRAL_TYPE_P (typea)
7005 && !POINTER_TYPE_P (typea))
7008 if (TREE_CODE (ineq) == LT_EXPR)
7010 a1 = TREE_OPERAND (ineq, 1);
7011 y = TREE_OPERAND (ineq, 0);
7013 else if (TREE_CODE (ineq) == GT_EXPR)
7015 a1 = TREE_OPERAND (ineq, 0);
7016 y = TREE_OPERAND (ineq, 1);
7021 if (TREE_TYPE (a1) != typea)
7024 if (POINTER_TYPE_P (typea))
7026 /* Convert the pointer types into integer before taking the difference. */
7027 tree ta = fold_convert (ssizetype, a);
7028 tree ta1 = fold_convert (ssizetype, a1);
7029 diff = fold_binary (MINUS_EXPR, ssizetype, ta1, ta);
7032 diff = fold_binary (MINUS_EXPR, typea, a1, a);
7034 if (!diff || !integer_onep (diff))
7037 return fold_build2 (GE_EXPR, type, a, y);
7040 /* Fold a sum or difference of at least one multiplication.
7041 Returns the folded tree or NULL if no simplification could be made. */
7044 fold_plusminus_mult_expr (enum tree_code code, tree type, tree arg0, tree arg1)
7046 tree arg00, arg01, arg10, arg11;
7047 tree alt0 = NULL_TREE, alt1 = NULL_TREE, same;
7049 /* (A * C) +- (B * C) -> (A+-B) * C.
7050 (A * C) +- A -> A * (C+-1).
7051 We are most concerned about the case where C is a constant,
7052 but other combinations show up during loop reduction. Since
7053 it is not difficult, try all four possibilities. */
7055 if (TREE_CODE (arg0) == MULT_EXPR)
7057 arg00 = TREE_OPERAND (arg0, 0);
7058 arg01 = TREE_OPERAND (arg0, 1);
7060 else if (TREE_CODE (arg0) == INTEGER_CST)
7062 arg00 = build_one_cst (type);
7067 /* We cannot generate constant 1 for fract. */
7068 if (ALL_FRACT_MODE_P (TYPE_MODE (type)))
7071 arg01 = build_one_cst (type);
7073 if (TREE_CODE (arg1) == MULT_EXPR)
7075 arg10 = TREE_OPERAND (arg1, 0);
7076 arg11 = TREE_OPERAND (arg1, 1);
7078 else if (TREE_CODE (arg1) == INTEGER_CST)
7080 arg10 = build_one_cst (type);
7085 /* We cannot generate constant 1 for fract. */
7086 if (ALL_FRACT_MODE_P (TYPE_MODE (type)))
7089 arg11 = build_one_cst (type);
7093 if (operand_equal_p (arg01, arg11, 0))
7094 same = arg01, alt0 = arg00, alt1 = arg10;
7095 else if (operand_equal_p (arg00, arg10, 0))
7096 same = arg00, alt0 = arg01, alt1 = arg11;
7097 else if (operand_equal_p (arg00, arg11, 0))
7098 same = arg00, alt0 = arg01, alt1 = arg10;
7099 else if (operand_equal_p (arg01, arg10, 0))
7100 same = arg01, alt0 = arg00, alt1 = arg11;
7102 /* No identical multiplicands; see if we can find a common
7103 power-of-two factor in non-power-of-two multiplies. This
7104 can help in multi-dimensional array access. */
7105 else if (host_integerp (arg01, 0)
7106 && host_integerp (arg11, 0))
7108 HOST_WIDE_INT int01, int11, tmp;
7111 int01 = TREE_INT_CST_LOW (arg01);
7112 int11 = TREE_INT_CST_LOW (arg11);
7114 /* Move min of absolute values to int11. */
7115 if ((int01 >= 0 ? int01 : -int01)
7116 < (int11 >= 0 ? int11 : -int11))
7118 tmp = int01, int01 = int11, int11 = tmp;
7119 alt0 = arg00, arg00 = arg10, arg10 = alt0;
7126 if (exact_log2 (abs (int11)) > 0 && int01 % int11 == 0)
7128 alt0 = fold_build2 (MULT_EXPR, TREE_TYPE (arg00), arg00,
7129 build_int_cst (TREE_TYPE (arg00),
7134 maybe_same = alt0, alt0 = alt1, alt1 = maybe_same;
7139 return fold_build2 (MULT_EXPR, type,
7140 fold_build2 (code, type,
7141 fold_convert (type, alt0),
7142 fold_convert (type, alt1)),
7143 fold_convert (type, same));
7148 /* Subroutine of native_encode_expr. Encode the INTEGER_CST
7149 specified by EXPR into the buffer PTR of length LEN bytes.
7150 Return the number of bytes placed in the buffer, or zero
7154 native_encode_int (const_tree expr, unsigned char *ptr, int len)
7156 tree type = TREE_TYPE (expr);
7157 int total_bytes = GET_MODE_SIZE (TYPE_MODE (type));
7158 int byte, offset, word, words;
7159 unsigned char value;
7161 if (total_bytes > len)
7163 words = total_bytes / UNITS_PER_WORD;
7165 for (byte = 0; byte < total_bytes; byte++)
7167 int bitpos = byte * BITS_PER_UNIT;
7168 if (bitpos < HOST_BITS_PER_WIDE_INT)
7169 value = (unsigned char) (TREE_INT_CST_LOW (expr) >> bitpos);
7171 value = (unsigned char) (TREE_INT_CST_HIGH (expr)
7172 >> (bitpos - HOST_BITS_PER_WIDE_INT));
7174 if (total_bytes > UNITS_PER_WORD)
7176 word = byte / UNITS_PER_WORD;
7177 if (WORDS_BIG_ENDIAN)
7178 word = (words - 1) - word;
7179 offset = word * UNITS_PER_WORD;
7180 if (BYTES_BIG_ENDIAN)
7181 offset += (UNITS_PER_WORD - 1) - (byte % UNITS_PER_WORD);
7183 offset += byte % UNITS_PER_WORD;
7186 offset = BYTES_BIG_ENDIAN ? (total_bytes - 1) - byte : byte;
7187 ptr[offset] = value;
7193 /* Subroutine of native_encode_expr. Encode the REAL_CST
7194 specified by EXPR into the buffer PTR of length LEN bytes.
7195 Return the number of bytes placed in the buffer, or zero
7199 native_encode_real (const_tree expr, unsigned char *ptr, int len)
7201 tree type = TREE_TYPE (expr);
7202 int total_bytes = GET_MODE_SIZE (TYPE_MODE (type));
7203 int byte, offset, word, words, bitpos;
7204 unsigned char value;
7206 /* There are always 32 bits in each long, no matter the size of
7207 the hosts long. We handle floating point representations with
7211 if (total_bytes > len)
7213 words = 32 / UNITS_PER_WORD;
7215 real_to_target (tmp, TREE_REAL_CST_PTR (expr), TYPE_MODE (type));
7217 for (bitpos = 0; bitpos < total_bytes * BITS_PER_UNIT;
7218 bitpos += BITS_PER_UNIT)
7220 byte = (bitpos / BITS_PER_UNIT) & 3;
7221 value = (unsigned char) (tmp[bitpos / 32] >> (bitpos & 31));
7223 if (UNITS_PER_WORD < 4)
7225 word = byte / UNITS_PER_WORD;
7226 if (WORDS_BIG_ENDIAN)
7227 word = (words - 1) - word;
7228 offset = word * UNITS_PER_WORD;
7229 if (BYTES_BIG_ENDIAN)
7230 offset += (UNITS_PER_WORD - 1) - (byte % UNITS_PER_WORD);
7232 offset += byte % UNITS_PER_WORD;
7235 offset = BYTES_BIG_ENDIAN ? 3 - byte : byte;
7236 ptr[offset + ((bitpos / BITS_PER_UNIT) & ~3)] = value;
7241 /* Subroutine of native_encode_expr. Encode the COMPLEX_CST
7242 specified by EXPR into the buffer PTR of length LEN bytes.
7243 Return the number of bytes placed in the buffer, or zero
7247 native_encode_complex (const_tree expr, unsigned char *ptr, int len)
7252 part = TREE_REALPART (expr);
7253 rsize = native_encode_expr (part, ptr, len);
7256 part = TREE_IMAGPART (expr);
7257 isize = native_encode_expr (part, ptr+rsize, len-rsize);
7260 return rsize + isize;
7264 /* Subroutine of native_encode_expr. Encode the VECTOR_CST
7265 specified by EXPR into the buffer PTR of length LEN bytes.
7266 Return the number of bytes placed in the buffer, or zero
7270 native_encode_vector (const_tree expr, unsigned char *ptr, int len)
7272 int i, size, offset, count;
7273 tree itype, elem, elements;
7276 elements = TREE_VECTOR_CST_ELTS (expr);
7277 count = TYPE_VECTOR_SUBPARTS (TREE_TYPE (expr));
7278 itype = TREE_TYPE (TREE_TYPE (expr));
7279 size = GET_MODE_SIZE (TYPE_MODE (itype));
7280 for (i = 0; i < count; i++)
7284 elem = TREE_VALUE (elements);
7285 elements = TREE_CHAIN (elements);
7292 if (native_encode_expr (elem, ptr+offset, len-offset) != size)
7297 if (offset + size > len)
7299 memset (ptr+offset, 0, size);
7307 /* Subroutine of fold_view_convert_expr. Encode the INTEGER_CST,
7308 REAL_CST, COMPLEX_CST or VECTOR_CST specified by EXPR into the
7309 buffer PTR of length LEN bytes. Return the number of bytes
7310 placed in the buffer, or zero upon failure. */
7313 native_encode_expr (const_tree expr, unsigned char *ptr, int len)
7315 switch (TREE_CODE (expr))
7318 return native_encode_int (expr, ptr, len);
7321 return native_encode_real (expr, ptr, len);
7324 return native_encode_complex (expr, ptr, len);
7327 return native_encode_vector (expr, ptr, len);
7335 /* Subroutine of native_interpret_expr. Interpret the contents of
7336 the buffer PTR of length LEN as an INTEGER_CST of type TYPE.
7337 If the buffer cannot be interpreted, return NULL_TREE. */
7340 native_interpret_int (tree type, const unsigned char *ptr, int len)
7342 int total_bytes = GET_MODE_SIZE (TYPE_MODE (type));
7343 int byte, offset, word, words;
7344 unsigned char value;
7345 unsigned int HOST_WIDE_INT lo = 0;
7346 HOST_WIDE_INT hi = 0;
7348 if (total_bytes > len)
7350 if (total_bytes * BITS_PER_UNIT > 2 * HOST_BITS_PER_WIDE_INT)
7352 words = total_bytes / UNITS_PER_WORD;
7354 for (byte = 0; byte < total_bytes; byte++)
7356 int bitpos = byte * BITS_PER_UNIT;
7357 if (total_bytes > UNITS_PER_WORD)
7359 word = byte / UNITS_PER_WORD;
7360 if (WORDS_BIG_ENDIAN)
7361 word = (words - 1) - word;
7362 offset = word * UNITS_PER_WORD;
7363 if (BYTES_BIG_ENDIAN)
7364 offset += (UNITS_PER_WORD - 1) - (byte % UNITS_PER_WORD);
7366 offset += byte % UNITS_PER_WORD;
7369 offset = BYTES_BIG_ENDIAN ? (total_bytes - 1) - byte : byte;
7370 value = ptr[offset];
7372 if (bitpos < HOST_BITS_PER_WIDE_INT)
7373 lo |= (unsigned HOST_WIDE_INT) value << bitpos;
7375 hi |= (unsigned HOST_WIDE_INT) value
7376 << (bitpos - HOST_BITS_PER_WIDE_INT);
7379 return build_int_cst_wide_type (type, lo, hi);
7383 /* Subroutine of native_interpret_expr. Interpret the contents of
7384 the buffer PTR of length LEN as a REAL_CST of type TYPE.
7385 If the buffer cannot be interpreted, return NULL_TREE. */
7388 native_interpret_real (tree type, const unsigned char *ptr, int len)
7390 enum machine_mode mode = TYPE_MODE (type);
7391 int total_bytes = GET_MODE_SIZE (mode);
7392 int byte, offset, word, words, bitpos;
7393 unsigned char value;
7394 /* There are always 32 bits in each long, no matter the size of
7395 the hosts long. We handle floating point representations with
7400 total_bytes = GET_MODE_SIZE (TYPE_MODE (type));
7401 if (total_bytes > len || total_bytes > 24)
7403 words = 32 / UNITS_PER_WORD;
7405 memset (tmp, 0, sizeof (tmp));
7406 for (bitpos = 0; bitpos < total_bytes * BITS_PER_UNIT;
7407 bitpos += BITS_PER_UNIT)
7409 byte = (bitpos / BITS_PER_UNIT) & 3;
7410 if (UNITS_PER_WORD < 4)
7412 word = byte / UNITS_PER_WORD;
7413 if (WORDS_BIG_ENDIAN)
7414 word = (words - 1) - word;
7415 offset = word * UNITS_PER_WORD;
7416 if (BYTES_BIG_ENDIAN)
7417 offset += (UNITS_PER_WORD - 1) - (byte % UNITS_PER_WORD);
7419 offset += byte % UNITS_PER_WORD;
7422 offset = BYTES_BIG_ENDIAN ? 3 - byte : byte;
7423 value = ptr[offset + ((bitpos / BITS_PER_UNIT) & ~3)];
7425 tmp[bitpos / 32] |= (unsigned long)value << (bitpos & 31);
7428 real_from_target (&r, tmp, mode);
7429 return build_real (type, r);
7433 /* Subroutine of native_interpret_expr. Interpret the contents of
7434 the buffer PTR of length LEN as a COMPLEX_CST of type TYPE.
7435 If the buffer cannot be interpreted, return NULL_TREE. */
7438 native_interpret_complex (tree type, const unsigned char *ptr, int len)
7440 tree etype, rpart, ipart;
7443 etype = TREE_TYPE (type);
7444 size = GET_MODE_SIZE (TYPE_MODE (etype));
7447 rpart = native_interpret_expr (etype, ptr, size);
7450 ipart = native_interpret_expr (etype, ptr+size, size);
7453 return build_complex (type, rpart, ipart);
7457 /* Subroutine of native_interpret_expr. Interpret the contents of
7458 the buffer PTR of length LEN as a VECTOR_CST of type TYPE.
7459 If the buffer cannot be interpreted, return NULL_TREE. */
7462 native_interpret_vector (tree type, const unsigned char *ptr, int len)
7464 tree etype, elem, elements;
7467 etype = TREE_TYPE (type);
7468 size = GET_MODE_SIZE (TYPE_MODE (etype));
7469 count = TYPE_VECTOR_SUBPARTS (type);
7470 if (size * count > len)
7473 elements = NULL_TREE;
7474 for (i = count - 1; i >= 0; i--)
7476 elem = native_interpret_expr (etype, ptr+(i*size), size);
7479 elements = tree_cons (NULL_TREE, elem, elements);
7481 return build_vector (type, elements);
7485 /* Subroutine of fold_view_convert_expr. Interpret the contents of
7486 the buffer PTR of length LEN as a constant of type TYPE. For
7487 INTEGRAL_TYPE_P we return an INTEGER_CST, for SCALAR_FLOAT_TYPE_P
7488 we return a REAL_CST, etc... If the buffer cannot be interpreted,
7489 return NULL_TREE. */
7492 native_interpret_expr (tree type, const unsigned char *ptr, int len)
7494 switch (TREE_CODE (type))
7499 return native_interpret_int (type, ptr, len);
7502 return native_interpret_real (type, ptr, len);
7505 return native_interpret_complex (type, ptr, len);
7508 return native_interpret_vector (type, ptr, len);
7516 /* Fold a VIEW_CONVERT_EXPR of a constant expression EXPR to type
7517 TYPE at compile-time. If we're unable to perform the conversion
7518 return NULL_TREE. */
7521 fold_view_convert_expr (tree type, tree expr)
7523 /* We support up to 512-bit values (for V8DFmode). */
7524 unsigned char buffer[64];
7527 /* Check that the host and target are sane. */
7528 if (CHAR_BIT != 8 || BITS_PER_UNIT != 8)
7531 len = native_encode_expr (expr, buffer, sizeof (buffer));
7535 return native_interpret_expr (type, buffer, len);
7538 /* Build an expression for the address of T. Folds away INDIRECT_REF
7539 to avoid confusing the gimplify process. When IN_FOLD is true
7540 avoid modifications of T. */
7543 build_fold_addr_expr_with_type_1 (tree t, tree ptrtype, bool in_fold)
7545 /* The size of the object is not relevant when talking about its address. */
7546 if (TREE_CODE (t) == WITH_SIZE_EXPR)
7547 t = TREE_OPERAND (t, 0);
7549 /* Note: doesn't apply to ALIGN_INDIRECT_REF */
7550 if (TREE_CODE (t) == INDIRECT_REF
7551 || TREE_CODE (t) == MISALIGNED_INDIRECT_REF)
7553 t = TREE_OPERAND (t, 0);
7555 if (TREE_TYPE (t) != ptrtype)
7556 t = build1 (NOP_EXPR, ptrtype, t);
7562 while (handled_component_p (base))
7563 base = TREE_OPERAND (base, 0);
7566 TREE_ADDRESSABLE (base) = 1;
7568 t = build1 (ADDR_EXPR, ptrtype, t);
7571 t = build1 (ADDR_EXPR, ptrtype, t);
7576 /* Build an expression for the address of T with type PTRTYPE. This
7577 function modifies the input parameter 'T' by sometimes setting the
7578 TREE_ADDRESSABLE flag. */
7581 build_fold_addr_expr_with_type (tree t, tree ptrtype)
7583 return build_fold_addr_expr_with_type_1 (t, ptrtype, false);
7586 /* Build an expression for the address of T. This function modifies
7587 the input parameter 'T' by sometimes setting the TREE_ADDRESSABLE
7588 flag. When called from fold functions, use fold_addr_expr instead. */
7591 build_fold_addr_expr (tree t)
7593 return build_fold_addr_expr_with_type_1 (t,
7594 build_pointer_type (TREE_TYPE (t)),
7598 /* Same as build_fold_addr_expr, builds an expression for the address
7599 of T, but avoids touching the input node 't'. Fold functions
7600 should use this version. */
7603 fold_addr_expr (tree t)
7605 tree ptrtype = build_pointer_type (TREE_TYPE (t));
7607 return build_fold_addr_expr_with_type_1 (t, ptrtype, true);
7610 /* Fold a unary expression of code CODE and type TYPE with operand
7611 OP0. Return the folded expression if folding is successful.
7612 Otherwise, return NULL_TREE. */
7615 fold_unary (enum tree_code code, tree type, tree op0)
7619 enum tree_code_class kind = TREE_CODE_CLASS (code);
7621 gcc_assert (IS_EXPR_CODE_CLASS (kind)
7622 && TREE_CODE_LENGTH (code) == 1);
7627 if (code == NOP_EXPR || code == CONVERT_EXPR
7628 || code == FLOAT_EXPR || code == ABS_EXPR)
7630 /* Don't use STRIP_NOPS, because signedness of argument type
7632 STRIP_SIGN_NOPS (arg0);
7636 /* Strip any conversions that don't change the mode. This
7637 is safe for every expression, except for a comparison
7638 expression because its signedness is derived from its
7641 Note that this is done as an internal manipulation within
7642 the constant folder, in order to find the simplest
7643 representation of the arguments so that their form can be
7644 studied. In any cases, the appropriate type conversions
7645 should be put back in the tree that will get out of the
7651 if (TREE_CODE_CLASS (code) == tcc_unary)
7653 if (TREE_CODE (arg0) == COMPOUND_EXPR)
7654 return build2 (COMPOUND_EXPR, type, TREE_OPERAND (arg0, 0),
7655 fold_build1 (code, type, TREE_OPERAND (arg0, 1)));
7656 else if (TREE_CODE (arg0) == COND_EXPR)
7658 tree arg01 = TREE_OPERAND (arg0, 1);
7659 tree arg02 = TREE_OPERAND (arg0, 2);
7660 if (! VOID_TYPE_P (TREE_TYPE (arg01)))
7661 arg01 = fold_build1 (code, type, arg01);
7662 if (! VOID_TYPE_P (TREE_TYPE (arg02)))
7663 arg02 = fold_build1 (code, type, arg02);
7664 tem = fold_build3 (COND_EXPR, type, TREE_OPERAND (arg0, 0),
7667 /* If this was a conversion, and all we did was to move into
7668 inside the COND_EXPR, bring it back out. But leave it if
7669 it is a conversion from integer to integer and the
7670 result precision is no wider than a word since such a
7671 conversion is cheap and may be optimized away by combine,
7672 while it couldn't if it were outside the COND_EXPR. Then return
7673 so we don't get into an infinite recursion loop taking the
7674 conversion out and then back in. */
7676 if ((code == NOP_EXPR || code == CONVERT_EXPR
7677 || code == NON_LVALUE_EXPR)
7678 && TREE_CODE (tem) == COND_EXPR
7679 && TREE_CODE (TREE_OPERAND (tem, 1)) == code
7680 && TREE_CODE (TREE_OPERAND (tem, 2)) == code
7681 && ! VOID_TYPE_P (TREE_OPERAND (tem, 1))
7682 && ! VOID_TYPE_P (TREE_OPERAND (tem, 2))
7683 && (TREE_TYPE (TREE_OPERAND (TREE_OPERAND (tem, 1), 0))
7684 == TREE_TYPE (TREE_OPERAND (TREE_OPERAND (tem, 2), 0)))
7685 && (! (INTEGRAL_TYPE_P (TREE_TYPE (tem))
7687 (TREE_TYPE (TREE_OPERAND (TREE_OPERAND (tem, 1), 0))))
7688 && TYPE_PRECISION (TREE_TYPE (tem)) <= BITS_PER_WORD)
7689 || flag_syntax_only))
7690 tem = build1 (code, type,
7692 TREE_TYPE (TREE_OPERAND
7693 (TREE_OPERAND (tem, 1), 0)),
7694 TREE_OPERAND (tem, 0),
7695 TREE_OPERAND (TREE_OPERAND (tem, 1), 0),
7696 TREE_OPERAND (TREE_OPERAND (tem, 2), 0)));
7699 else if (COMPARISON_CLASS_P (arg0))
7701 if (TREE_CODE (type) == BOOLEAN_TYPE)
7703 arg0 = copy_node (arg0);
7704 TREE_TYPE (arg0) = type;
7707 else if (TREE_CODE (type) != INTEGER_TYPE)
7708 return fold_build3 (COND_EXPR, type, arg0,
7709 fold_build1 (code, type,
7711 fold_build1 (code, type,
7712 integer_zero_node));
7719 /* Re-association barriers around constants and other re-association
7720 barriers can be removed. */
7721 if (CONSTANT_CLASS_P (op0)
7722 || TREE_CODE (op0) == PAREN_EXPR)
7723 return fold_convert (type, op0);
7729 case FIX_TRUNC_EXPR:
7730 if (TREE_TYPE (op0) == type)
7733 /* If we have (type) (a CMP b) and type is an integral type, return
7734 new expression involving the new type. */
7735 if (COMPARISON_CLASS_P (op0) && INTEGRAL_TYPE_P (type))
7736 return fold_build2 (TREE_CODE (op0), type, TREE_OPERAND (op0, 0),
7737 TREE_OPERAND (op0, 1));
7739 /* Handle cases of two conversions in a row. */
7740 if (TREE_CODE (op0) == NOP_EXPR
7741 || TREE_CODE (op0) == CONVERT_EXPR)
7743 tree inside_type = TREE_TYPE (TREE_OPERAND (op0, 0));
7744 tree inter_type = TREE_TYPE (op0);
7745 int inside_int = INTEGRAL_TYPE_P (inside_type);
7746 int inside_ptr = POINTER_TYPE_P (inside_type);
7747 int inside_float = FLOAT_TYPE_P (inside_type);
7748 int inside_vec = TREE_CODE (inside_type) == VECTOR_TYPE;
7749 unsigned int inside_prec = TYPE_PRECISION (inside_type);
7750 int inside_unsignedp = TYPE_UNSIGNED (inside_type);
7751 int inter_int = INTEGRAL_TYPE_P (inter_type);
7752 int inter_ptr = POINTER_TYPE_P (inter_type);
7753 int inter_float = FLOAT_TYPE_P (inter_type);
7754 int inter_vec = TREE_CODE (inter_type) == VECTOR_TYPE;
7755 unsigned int inter_prec = TYPE_PRECISION (inter_type);
7756 int inter_unsignedp = TYPE_UNSIGNED (inter_type);
7757 int final_int = INTEGRAL_TYPE_P (type);
7758 int final_ptr = POINTER_TYPE_P (type);
7759 int final_float = FLOAT_TYPE_P (type);
7760 int final_vec = TREE_CODE (type) == VECTOR_TYPE;
7761 unsigned int final_prec = TYPE_PRECISION (type);
7762 int final_unsignedp = TYPE_UNSIGNED (type);
7764 /* In addition to the cases of two conversions in a row
7765 handled below, if we are converting something to its own
7766 type via an object of identical or wider precision, neither
7767 conversion is needed. */
7768 if (TYPE_MAIN_VARIANT (inside_type) == TYPE_MAIN_VARIANT (type)
7769 && (((inter_int || inter_ptr) && final_int)
7770 || (inter_float && final_float))
7771 && inter_prec >= final_prec)
7772 return fold_build1 (code, type, TREE_OPERAND (op0, 0));
7774 /* Likewise, if the intermediate and final types are either both
7775 float or both integer, we don't need the middle conversion if
7776 it is wider than the final type and doesn't change the signedness
7777 (for integers). Avoid this if the final type is a pointer
7778 since then we sometimes need the inner conversion. Likewise if
7779 the outer has a precision not equal to the size of its mode. */
7780 if (((inter_int && inside_int)
7781 || (inter_float && inside_float)
7782 || (inter_vec && inside_vec))
7783 && inter_prec >= inside_prec
7784 && (inter_float || inter_vec
7785 || inter_unsignedp == inside_unsignedp)
7786 && ! (final_prec != GET_MODE_BITSIZE (TYPE_MODE (type))
7787 && TYPE_MODE (type) == TYPE_MODE (inter_type))
7789 && (! final_vec || inter_prec == inside_prec))
7790 return fold_build1 (code, type, TREE_OPERAND (op0, 0));
7792 /* If we have a sign-extension of a zero-extended value, we can
7793 replace that by a single zero-extension. */
7794 if (inside_int && inter_int && final_int
7795 && inside_prec < inter_prec && inter_prec < final_prec
7796 && inside_unsignedp && !inter_unsignedp)
7797 return fold_build1 (code, type, TREE_OPERAND (op0, 0));
7799 /* Two conversions in a row are not needed unless:
7800 - some conversion is floating-point (overstrict for now), or
7801 - some conversion is a vector (overstrict for now), or
7802 - the intermediate type is narrower than both initial and
7804 - the intermediate type and innermost type differ in signedness,
7805 and the outermost type is wider than the intermediate, or
7806 - the initial type is a pointer type and the precisions of the
7807 intermediate and final types differ, or
7808 - the final type is a pointer type and the precisions of the
7809 initial and intermediate types differ. */
7810 if (! inside_float && ! inter_float && ! final_float
7811 && ! inside_vec && ! inter_vec && ! final_vec
7812 && (inter_prec >= inside_prec || inter_prec >= final_prec)
7813 && ! (inside_int && inter_int
7814 && inter_unsignedp != inside_unsignedp
7815 && inter_prec < final_prec)
7816 && ((inter_unsignedp && inter_prec > inside_prec)
7817 == (final_unsignedp && final_prec > inter_prec))
7818 && ! (inside_ptr && inter_prec != final_prec)
7819 && ! (final_ptr && inside_prec != inter_prec)
7820 && ! (final_prec != GET_MODE_BITSIZE (TYPE_MODE (type))
7821 && TYPE_MODE (type) == TYPE_MODE (inter_type)))
7822 return fold_build1 (code, type, TREE_OPERAND (op0, 0));
7825 /* Handle (T *)&A.B.C for A being of type T and B and C
7826 living at offset zero. This occurs frequently in
7827 C++ upcasting and then accessing the base. */
7828 if (TREE_CODE (op0) == ADDR_EXPR
7829 && POINTER_TYPE_P (type)
7830 && handled_component_p (TREE_OPERAND (op0, 0)))
7832 HOST_WIDE_INT bitsize, bitpos;
7834 enum machine_mode mode;
7835 int unsignedp, volatilep;
7836 tree base = TREE_OPERAND (op0, 0);
7837 base = get_inner_reference (base, &bitsize, &bitpos, &offset,
7838 &mode, &unsignedp, &volatilep, false);
7839 /* If the reference was to a (constant) zero offset, we can use
7840 the address of the base if it has the same base type
7841 as the result type. */
7842 if (! offset && bitpos == 0
7843 && TYPE_MAIN_VARIANT (TREE_TYPE (type))
7844 == TYPE_MAIN_VARIANT (TREE_TYPE (base)))
7845 return fold_convert (type, fold_addr_expr (base));
7848 if ((TREE_CODE (op0) == MODIFY_EXPR
7849 || TREE_CODE (op0) == GIMPLE_MODIFY_STMT)
7850 && TREE_CONSTANT (GENERIC_TREE_OPERAND (op0, 1))
7851 /* Detect assigning a bitfield. */
7852 && !(TREE_CODE (GENERIC_TREE_OPERAND (op0, 0)) == COMPONENT_REF
7854 (TREE_OPERAND (GENERIC_TREE_OPERAND (op0, 0), 1))))
7856 /* Don't leave an assignment inside a conversion
7857 unless assigning a bitfield. */
7858 tem = fold_build1 (code, type, GENERIC_TREE_OPERAND (op0, 1));
7859 /* First do the assignment, then return converted constant. */
7860 tem = build2 (COMPOUND_EXPR, TREE_TYPE (tem), op0, tem);
7861 TREE_NO_WARNING (tem) = 1;
7862 TREE_USED (tem) = 1;
7866 /* Convert (T)(x & c) into (T)x & (T)c, if c is an integer
7867 constants (if x has signed type, the sign bit cannot be set
7868 in c). This folds extension into the BIT_AND_EXPR. */
7869 if (INTEGRAL_TYPE_P (type)
7870 && TREE_CODE (type) != BOOLEAN_TYPE
7871 && TREE_CODE (op0) == BIT_AND_EXPR
7872 && TREE_CODE (TREE_OPERAND (op0, 1)) == INTEGER_CST)
7875 tree and0 = TREE_OPERAND (and, 0), and1 = TREE_OPERAND (and, 1);
7878 if (TYPE_UNSIGNED (TREE_TYPE (and))
7879 || (TYPE_PRECISION (type)
7880 <= TYPE_PRECISION (TREE_TYPE (and))))
7882 else if (TYPE_PRECISION (TREE_TYPE (and1))
7883 <= HOST_BITS_PER_WIDE_INT
7884 && host_integerp (and1, 1))
7886 unsigned HOST_WIDE_INT cst;
7888 cst = tree_low_cst (and1, 1);
7889 cst &= (HOST_WIDE_INT) -1
7890 << (TYPE_PRECISION (TREE_TYPE (and1)) - 1);
7891 change = (cst == 0);
7892 #ifdef LOAD_EXTEND_OP
7894 && !flag_syntax_only
7895 && (LOAD_EXTEND_OP (TYPE_MODE (TREE_TYPE (and0)))
7898 tree uns = unsigned_type_for (TREE_TYPE (and0));
7899 and0 = fold_convert (uns, and0);
7900 and1 = fold_convert (uns, and1);
7906 tem = force_fit_type_double (type, TREE_INT_CST_LOW (and1),
7907 TREE_INT_CST_HIGH (and1), 0,
7908 TREE_OVERFLOW (and1));
7909 return fold_build2 (BIT_AND_EXPR, type,
7910 fold_convert (type, and0), tem);
7914 /* Convert (T1)(X p+ Y) into ((T1)X p+ Y), for pointer type,
7915 when one of the new casts will fold away. Conservatively we assume
7916 that this happens when X or Y is NOP_EXPR or Y is INTEGER_CST. */
7917 if (POINTER_TYPE_P (type)
7918 && TREE_CODE (arg0) == POINTER_PLUS_EXPR
7919 && (TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST
7920 || TREE_CODE (TREE_OPERAND (arg0, 0)) == NOP_EXPR
7921 || TREE_CODE (TREE_OPERAND (arg0, 1)) == NOP_EXPR))
7923 tree arg00 = TREE_OPERAND (arg0, 0);
7924 tree arg01 = TREE_OPERAND (arg0, 1);
7926 return fold_build2 (TREE_CODE (arg0), type, fold_convert (type, arg00),
7927 fold_convert (sizetype, arg01));
7930 /* Convert (T1)(~(T2)X) into ~(T1)X if T1 and T2 are integral types
7931 of the same precision, and X is an integer type not narrower than
7932 types T1 or T2, i.e. the cast (T2)X isn't an extension. */
7933 if (INTEGRAL_TYPE_P (type)
7934 && TREE_CODE (op0) == BIT_NOT_EXPR
7935 && INTEGRAL_TYPE_P (TREE_TYPE (op0))
7936 && (TREE_CODE (TREE_OPERAND (op0, 0)) == NOP_EXPR
7937 || TREE_CODE (TREE_OPERAND (op0, 0)) == CONVERT_EXPR)
7938 && TYPE_PRECISION (type) == TYPE_PRECISION (TREE_TYPE (op0)))
7940 tem = TREE_OPERAND (TREE_OPERAND (op0, 0), 0);
7941 if (INTEGRAL_TYPE_P (TREE_TYPE (tem))
7942 && TYPE_PRECISION (type) <= TYPE_PRECISION (TREE_TYPE (tem)))
7943 return fold_build1 (BIT_NOT_EXPR, type, fold_convert (type, tem));
7946 /* Convert (T1)(X * Y) into (T1)X * (T1)Y if T1 is narrower than the
7947 type of X and Y (integer types only). */
7948 if (INTEGRAL_TYPE_P (type)
7949 && TREE_CODE (op0) == MULT_EXPR
7950 && INTEGRAL_TYPE_P (TREE_TYPE (op0))
7951 && TYPE_PRECISION (type) < TYPE_PRECISION (TREE_TYPE (op0)))
7953 /* Be careful not to introduce new overflows. */
7955 if (TYPE_OVERFLOW_WRAPS (type))
7958 mult_type = unsigned_type_for (type);
7960 tem = fold_build2 (MULT_EXPR, mult_type,
7961 fold_convert (mult_type, TREE_OPERAND (op0, 0)),
7962 fold_convert (mult_type, TREE_OPERAND (op0, 1)));
7963 return fold_convert (type, tem);
7966 tem = fold_convert_const (code, type, op0);
7967 return tem ? tem : NULL_TREE;
7969 case FIXED_CONVERT_EXPR:
7970 tem = fold_convert_const (code, type, arg0);
7971 return tem ? tem : NULL_TREE;
7973 case VIEW_CONVERT_EXPR:
7974 if (TREE_TYPE (op0) == type)
7976 if (TREE_CODE (op0) == VIEW_CONVERT_EXPR)
7977 return fold_build1 (VIEW_CONVERT_EXPR, type, TREE_OPERAND (op0, 0));
7979 /* For integral conversions with the same precision or pointer
7980 conversions use a NOP_EXPR instead. */
7981 if ((INTEGRAL_TYPE_P (type)
7982 || POINTER_TYPE_P (type))
7983 && (INTEGRAL_TYPE_P (TREE_TYPE (op0))
7984 || POINTER_TYPE_P (TREE_TYPE (op0)))
7985 && TYPE_PRECISION (type) == TYPE_PRECISION (TREE_TYPE (op0))
7986 /* Do not muck with VIEW_CONVERT_EXPRs that convert from
7987 a sub-type to its base type as generated by the Ada FE. */
7988 && !(INTEGRAL_TYPE_P (TREE_TYPE (op0))
7989 && TREE_TYPE (TREE_TYPE (op0))))
7990 return fold_convert (type, op0);
7992 /* Strip inner integral conversions that do not change the precision. */
7993 if ((TREE_CODE (op0) == NOP_EXPR
7994 || TREE_CODE (op0) == CONVERT_EXPR)
7995 && (INTEGRAL_TYPE_P (TREE_TYPE (op0))
7996 || POINTER_TYPE_P (TREE_TYPE (op0)))
7997 && (INTEGRAL_TYPE_P (TREE_TYPE (TREE_OPERAND (op0, 0)))
7998 || POINTER_TYPE_P (TREE_TYPE (TREE_OPERAND (op0, 0))))
7999 && (TYPE_PRECISION (TREE_TYPE (op0))
8000 == TYPE_PRECISION (TREE_TYPE (TREE_OPERAND (op0, 0)))))
8001 return fold_build1 (VIEW_CONVERT_EXPR, type, TREE_OPERAND (op0, 0));
8003 return fold_view_convert_expr (type, op0);
8006 tem = fold_negate_expr (arg0);
8008 return fold_convert (type, tem);
8012 if (TREE_CODE (arg0) == INTEGER_CST || TREE_CODE (arg0) == REAL_CST)
8013 return fold_abs_const (arg0, type);
8014 else if (TREE_CODE (arg0) == NEGATE_EXPR)
8015 return fold_build1 (ABS_EXPR, type, TREE_OPERAND (arg0, 0));
8016 /* Convert fabs((double)float) into (double)fabsf(float). */
8017 else if (TREE_CODE (arg0) == NOP_EXPR
8018 && TREE_CODE (type) == REAL_TYPE)
8020 tree targ0 = strip_float_extensions (arg0);
8022 return fold_convert (type, fold_build1 (ABS_EXPR,
8026 /* ABS_EXPR<ABS_EXPR<x>> = ABS_EXPR<x> even if flag_wrapv is on. */
8027 else if (TREE_CODE (arg0) == ABS_EXPR)
8029 else if (tree_expr_nonnegative_p (arg0))
8032 /* Strip sign ops from argument. */
8033 if (TREE_CODE (type) == REAL_TYPE)
8035 tem = fold_strip_sign_ops (arg0);
8037 return fold_build1 (ABS_EXPR, type, fold_convert (type, tem));
8042 if (TREE_CODE (TREE_TYPE (arg0)) != COMPLEX_TYPE)
8043 return fold_convert (type, arg0);
8044 if (TREE_CODE (arg0) == COMPLEX_EXPR)
8046 tree itype = TREE_TYPE (type);
8047 tree rpart = fold_convert (itype, TREE_OPERAND (arg0, 0));
8048 tree ipart = fold_convert (itype, TREE_OPERAND (arg0, 1));
8049 return fold_build2 (COMPLEX_EXPR, type, rpart, negate_expr (ipart));
8051 if (TREE_CODE (arg0) == COMPLEX_CST)
8053 tree itype = TREE_TYPE (type);
8054 tree rpart = fold_convert (itype, TREE_REALPART (arg0));
8055 tree ipart = fold_convert (itype, TREE_IMAGPART (arg0));
8056 return build_complex (type, rpart, negate_expr (ipart));
8058 if (TREE_CODE (arg0) == CONJ_EXPR)
8059 return fold_convert (type, TREE_OPERAND (arg0, 0));
8063 if (TREE_CODE (arg0) == INTEGER_CST)
8064 return fold_not_const (arg0, type);
8065 else if (TREE_CODE (arg0) == BIT_NOT_EXPR)
8066 return fold_convert (type, TREE_OPERAND (arg0, 0));
8067 /* Convert ~ (-A) to A - 1. */
8068 else if (INTEGRAL_TYPE_P (type) && TREE_CODE (arg0) == NEGATE_EXPR)
8069 return fold_build2 (MINUS_EXPR, type,
8070 fold_convert (type, TREE_OPERAND (arg0, 0)),
8071 build_int_cst (type, 1));
8072 /* Convert ~ (A - 1) or ~ (A + -1) to -A. */
8073 else if (INTEGRAL_TYPE_P (type)
8074 && ((TREE_CODE (arg0) == MINUS_EXPR
8075 && integer_onep (TREE_OPERAND (arg0, 1)))
8076 || (TREE_CODE (arg0) == PLUS_EXPR
8077 && integer_all_onesp (TREE_OPERAND (arg0, 1)))))
8078 return fold_build1 (NEGATE_EXPR, type,
8079 fold_convert (type, TREE_OPERAND (arg0, 0)));
8080 /* Convert ~(X ^ Y) to ~X ^ Y or X ^ ~Y if ~X or ~Y simplify. */
8081 else if (TREE_CODE (arg0) == BIT_XOR_EXPR
8082 && (tem = fold_unary (BIT_NOT_EXPR, type,
8084 TREE_OPERAND (arg0, 0)))))
8085 return fold_build2 (BIT_XOR_EXPR, type, tem,
8086 fold_convert (type, TREE_OPERAND (arg0, 1)));
8087 else if (TREE_CODE (arg0) == BIT_XOR_EXPR
8088 && (tem = fold_unary (BIT_NOT_EXPR, type,
8090 TREE_OPERAND (arg0, 1)))))
8091 return fold_build2 (BIT_XOR_EXPR, type,
8092 fold_convert (type, TREE_OPERAND (arg0, 0)), tem);
8093 /* Perform BIT_NOT_EXPR on each element individually. */
8094 else if (TREE_CODE (arg0) == VECTOR_CST)
8096 tree elements = TREE_VECTOR_CST_ELTS (arg0), elem, list = NULL_TREE;
8097 int count = TYPE_VECTOR_SUBPARTS (type), i;
8099 for (i = 0; i < count; i++)
8103 elem = TREE_VALUE (elements);
8104 elem = fold_unary (BIT_NOT_EXPR, TREE_TYPE (type), elem);
8105 if (elem == NULL_TREE)
8107 elements = TREE_CHAIN (elements);
8110 elem = build_int_cst (TREE_TYPE (type), -1);
8111 list = tree_cons (NULL_TREE, elem, list);
8114 return build_vector (type, nreverse (list));
8119 case TRUTH_NOT_EXPR:
8120 /* The argument to invert_truthvalue must have Boolean type. */
8121 if (TREE_CODE (TREE_TYPE (arg0)) != BOOLEAN_TYPE)
8122 arg0 = fold_convert (boolean_type_node, arg0);
8124 /* Note that the operand of this must be an int
8125 and its values must be 0 or 1.
8126 ("true" is a fixed value perhaps depending on the language,
8127 but we don't handle values other than 1 correctly yet.) */
8128 tem = fold_truth_not_expr (arg0);
8131 return fold_convert (type, tem);
8134 if (TREE_CODE (TREE_TYPE (arg0)) != COMPLEX_TYPE)
8135 return fold_convert (type, arg0);
8136 if (TREE_CODE (arg0) == COMPLEX_EXPR)
8137 return omit_one_operand (type, TREE_OPERAND (arg0, 0),
8138 TREE_OPERAND (arg0, 1));
8139 if (TREE_CODE (arg0) == COMPLEX_CST)
8140 return fold_convert (type, TREE_REALPART (arg0));
8141 if (TREE_CODE (arg0) == PLUS_EXPR || TREE_CODE (arg0) == MINUS_EXPR)
8143 tree itype = TREE_TYPE (TREE_TYPE (arg0));
8144 tem = fold_build2 (TREE_CODE (arg0), itype,
8145 fold_build1 (REALPART_EXPR, itype,
8146 TREE_OPERAND (arg0, 0)),
8147 fold_build1 (REALPART_EXPR, itype,
8148 TREE_OPERAND (arg0, 1)));
8149 return fold_convert (type, tem);
8151 if (TREE_CODE (arg0) == CONJ_EXPR)
8153 tree itype = TREE_TYPE (TREE_TYPE (arg0));
8154 tem = fold_build1 (REALPART_EXPR, itype, TREE_OPERAND (arg0, 0));
8155 return fold_convert (type, tem);
8157 if (TREE_CODE (arg0) == CALL_EXPR)
8159 tree fn = get_callee_fndecl (arg0);
8160 if (fn && DECL_BUILT_IN_CLASS (fn) == BUILT_IN_NORMAL)
8161 switch (DECL_FUNCTION_CODE (fn))
8163 CASE_FLT_FN (BUILT_IN_CEXPI):
8164 fn = mathfn_built_in (type, BUILT_IN_COS);
8166 return build_call_expr (fn, 1, CALL_EXPR_ARG (arg0, 0));
8176 if (TREE_CODE (TREE_TYPE (arg0)) != COMPLEX_TYPE)
8177 return fold_convert (type, integer_zero_node);
8178 if (TREE_CODE (arg0) == COMPLEX_EXPR)
8179 return omit_one_operand (type, TREE_OPERAND (arg0, 1),
8180 TREE_OPERAND (arg0, 0));
8181 if (TREE_CODE (arg0) == COMPLEX_CST)
8182 return fold_convert (type, TREE_IMAGPART (arg0));
8183 if (TREE_CODE (arg0) == PLUS_EXPR || TREE_CODE (arg0) == MINUS_EXPR)
8185 tree itype = TREE_TYPE (TREE_TYPE (arg0));
8186 tem = fold_build2 (TREE_CODE (arg0), itype,
8187 fold_build1 (IMAGPART_EXPR, itype,
8188 TREE_OPERAND (arg0, 0)),
8189 fold_build1 (IMAGPART_EXPR, itype,
8190 TREE_OPERAND (arg0, 1)));
8191 return fold_convert (type, tem);
8193 if (TREE_CODE (arg0) == CONJ_EXPR)
8195 tree itype = TREE_TYPE (TREE_TYPE (arg0));
8196 tem = fold_build1 (IMAGPART_EXPR, itype, TREE_OPERAND (arg0, 0));
8197 return fold_convert (type, negate_expr (tem));
8199 if (TREE_CODE (arg0) == CALL_EXPR)
8201 tree fn = get_callee_fndecl (arg0);
8202 if (fn && DECL_BUILT_IN_CLASS (fn) == BUILT_IN_NORMAL)
8203 switch (DECL_FUNCTION_CODE (fn))
8205 CASE_FLT_FN (BUILT_IN_CEXPI):
8206 fn = mathfn_built_in (type, BUILT_IN_SIN);
8208 return build_call_expr (fn, 1, CALL_EXPR_ARG (arg0, 0));
8219 } /* switch (code) */
8222 /* Fold a binary expression of code CODE and type TYPE with operands
8223 OP0 and OP1, containing either a MIN-MAX or a MAX-MIN combination.
8224 Return the folded expression if folding is successful. Otherwise,
8225 return NULL_TREE. */
8228 fold_minmax (enum tree_code code, tree type, tree op0, tree op1)
8230 enum tree_code compl_code;
8232 if (code == MIN_EXPR)
8233 compl_code = MAX_EXPR;
8234 else if (code == MAX_EXPR)
8235 compl_code = MIN_EXPR;
8239 /* MIN (MAX (a, b), b) == b. */
8240 if (TREE_CODE (op0) == compl_code
8241 && operand_equal_p (TREE_OPERAND (op0, 1), op1, 0))
8242 return omit_one_operand (type, op1, TREE_OPERAND (op0, 0));
8244 /* MIN (MAX (b, a), b) == b. */
8245 if (TREE_CODE (op0) == compl_code
8246 && operand_equal_p (TREE_OPERAND (op0, 0), op1, 0)
8247 && reorder_operands_p (TREE_OPERAND (op0, 1), op1))
8248 return omit_one_operand (type, op1, TREE_OPERAND (op0, 1));
8250 /* MIN (a, MAX (a, b)) == a. */
8251 if (TREE_CODE (op1) == compl_code
8252 && operand_equal_p (op0, TREE_OPERAND (op1, 0), 0)
8253 && reorder_operands_p (op0, TREE_OPERAND (op1, 1)))
8254 return omit_one_operand (type, op0, TREE_OPERAND (op1, 1));
8256 /* MIN (a, MAX (b, a)) == a. */
8257 if (TREE_CODE (op1) == compl_code
8258 && operand_equal_p (op0, TREE_OPERAND (op1, 1), 0)
8259 && reorder_operands_p (op0, TREE_OPERAND (op1, 0)))
8260 return omit_one_operand (type, op0, TREE_OPERAND (op1, 0));
8265 /* Helper that tries to canonicalize the comparison ARG0 CODE ARG1
8266 by changing CODE to reduce the magnitude of constants involved in
8267 ARG0 of the comparison.
8268 Returns a canonicalized comparison tree if a simplification was
8269 possible, otherwise returns NULL_TREE.
8270 Set *STRICT_OVERFLOW_P to true if the canonicalization is only
8271 valid if signed overflow is undefined. */
8274 maybe_canonicalize_comparison_1 (enum tree_code code, tree type,
8275 tree arg0, tree arg1,
8276 bool *strict_overflow_p)
8278 enum tree_code code0 = TREE_CODE (arg0);
8279 tree t, cst0 = NULL_TREE;
8283 /* Match A +- CST code arg1 and CST code arg1. */
8284 if (!(((code0 == MINUS_EXPR
8285 || code0 == PLUS_EXPR)
8286 && TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST)
8287 || code0 == INTEGER_CST))
8290 /* Identify the constant in arg0 and its sign. */
8291 if (code0 == INTEGER_CST)
8294 cst0 = TREE_OPERAND (arg0, 1);
8295 sgn0 = tree_int_cst_sgn (cst0);
8297 /* Overflowed constants and zero will cause problems. */
8298 if (integer_zerop (cst0)
8299 || TREE_OVERFLOW (cst0))
8302 /* See if we can reduce the magnitude of the constant in
8303 arg0 by changing the comparison code. */
8304 if (code0 == INTEGER_CST)
8306 /* CST <= arg1 -> CST-1 < arg1. */
8307 if (code == LE_EXPR && sgn0 == 1)
8309 /* -CST < arg1 -> -CST-1 <= arg1. */
8310 else if (code == LT_EXPR && sgn0 == -1)
8312 /* CST > arg1 -> CST-1 >= arg1. */
8313 else if (code == GT_EXPR && sgn0 == 1)
8315 /* -CST >= arg1 -> -CST-1 > arg1. */
8316 else if (code == GE_EXPR && sgn0 == -1)
8320 /* arg1 code' CST' might be more canonical. */
8325 /* A - CST < arg1 -> A - CST-1 <= arg1. */
8327 && code0 == ((sgn0 == -1) ? PLUS_EXPR : MINUS_EXPR))
8329 /* A + CST > arg1 -> A + CST-1 >= arg1. */
8330 else if (code == GT_EXPR
8331 && code0 == ((sgn0 == -1) ? MINUS_EXPR : PLUS_EXPR))
8333 /* A + CST <= arg1 -> A + CST-1 < arg1. */
8334 else if (code == LE_EXPR
8335 && code0 == ((sgn0 == -1) ? MINUS_EXPR : PLUS_EXPR))
8337 /* A - CST >= arg1 -> A - CST-1 > arg1. */
8338 else if (code == GE_EXPR
8339 && code0 == ((sgn0 == -1) ? PLUS_EXPR : MINUS_EXPR))
8343 *strict_overflow_p = true;
8346 /* Now build the constant reduced in magnitude. */
8347 t = int_const_binop (sgn0 == -1 ? PLUS_EXPR : MINUS_EXPR,
8348 cst0, build_int_cst (TREE_TYPE (cst0), 1), 0);
8349 if (code0 != INTEGER_CST)
8350 t = fold_build2 (code0, TREE_TYPE (arg0), TREE_OPERAND (arg0, 0), t);
8352 /* If swapping might yield to a more canonical form, do so. */
8354 return fold_build2 (swap_tree_comparison (code), type, arg1, t);
8356 return fold_build2 (code, type, t, arg1);
8359 /* Canonicalize the comparison ARG0 CODE ARG1 with type TYPE with undefined
8360 overflow further. Try to decrease the magnitude of constants involved
8361 by changing LE_EXPR and GE_EXPR to LT_EXPR and GT_EXPR or vice versa
8362 and put sole constants at the second argument position.
8363 Returns the canonicalized tree if changed, otherwise NULL_TREE. */
8366 maybe_canonicalize_comparison (enum tree_code code, tree type,
8367 tree arg0, tree arg1)
8370 bool strict_overflow_p;
8371 const char * const warnmsg = G_("assuming signed overflow does not occur "
8372 "when reducing constant in comparison");
8374 /* In principle pointers also have undefined overflow behavior,
8375 but that causes problems elsewhere. */
8376 if (!TYPE_OVERFLOW_UNDEFINED (TREE_TYPE (arg0))
8377 || POINTER_TYPE_P (TREE_TYPE (arg0)))
8380 /* Try canonicalization by simplifying arg0. */
8381 strict_overflow_p = false;
8382 t = maybe_canonicalize_comparison_1 (code, type, arg0, arg1,
8383 &strict_overflow_p);
8386 if (strict_overflow_p)
8387 fold_overflow_warning (warnmsg, WARN_STRICT_OVERFLOW_MAGNITUDE);
8391 /* Try canonicalization by simplifying arg1 using the swapped
8393 code = swap_tree_comparison (code);
8394 strict_overflow_p = false;
8395 t = maybe_canonicalize_comparison_1 (code, type, arg1, arg0,
8396 &strict_overflow_p);
8397 if (t && strict_overflow_p)
8398 fold_overflow_warning (warnmsg, WARN_STRICT_OVERFLOW_MAGNITUDE);
8402 /* Return whether BASE + OFFSET + BITPOS may wrap around the address
8403 space. This is used to avoid issuing overflow warnings for
8404 expressions like &p->x which can not wrap. */
8407 pointer_may_wrap_p (tree base, tree offset, HOST_WIDE_INT bitpos)
8409 unsigned HOST_WIDE_INT offset_low, total_low;
8410 HOST_WIDE_INT size, offset_high, total_high;
8412 if (!POINTER_TYPE_P (TREE_TYPE (base)))
8418 if (offset == NULL_TREE)
8423 else if (TREE_CODE (offset) != INTEGER_CST || TREE_OVERFLOW (offset))
8427 offset_low = TREE_INT_CST_LOW (offset);
8428 offset_high = TREE_INT_CST_HIGH (offset);
8431 if (add_double_with_sign (offset_low, offset_high,
8432 bitpos / BITS_PER_UNIT, 0,
8433 &total_low, &total_high,
8437 if (total_high != 0)
8440 size = int_size_in_bytes (TREE_TYPE (TREE_TYPE (base)));
8444 /* We can do slightly better for SIZE if we have an ADDR_EXPR of an
8446 if (TREE_CODE (base) == ADDR_EXPR)
8448 HOST_WIDE_INT base_size;
8450 base_size = int_size_in_bytes (TREE_TYPE (TREE_OPERAND (base, 0)));
8451 if (base_size > 0 && size < base_size)
8455 return total_low > (unsigned HOST_WIDE_INT) size;
8458 /* Subroutine of fold_binary. This routine performs all of the
8459 transformations that are common to the equality/inequality
8460 operators (EQ_EXPR and NE_EXPR) and the ordering operators
8461 (LT_EXPR, LE_EXPR, GE_EXPR and GT_EXPR). Callers other than
8462 fold_binary should call fold_binary. Fold a comparison with
8463 tree code CODE and type TYPE with operands OP0 and OP1. Return
8464 the folded comparison or NULL_TREE. */
8467 fold_comparison (enum tree_code code, tree type, tree op0, tree op1)
8469 tree arg0, arg1, tem;
8474 STRIP_SIGN_NOPS (arg0);
8475 STRIP_SIGN_NOPS (arg1);
8477 tem = fold_relational_const (code, type, arg0, arg1);
8478 if (tem != NULL_TREE)
8481 /* If one arg is a real or integer constant, put it last. */
8482 if (tree_swap_operands_p (arg0, arg1, true))
8483 return fold_build2 (swap_tree_comparison (code), type, op1, op0);
8485 /* Transform comparisons of the form X +- C1 CMP C2 to X CMP C2 +- C1. */
8486 if ((TREE_CODE (arg0) == PLUS_EXPR || TREE_CODE (arg0) == MINUS_EXPR)
8487 && (TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST
8488 && !TREE_OVERFLOW (TREE_OPERAND (arg0, 1))
8489 && TYPE_OVERFLOW_UNDEFINED (TREE_TYPE (arg1)))
8490 && (TREE_CODE (arg1) == INTEGER_CST
8491 && !TREE_OVERFLOW (arg1)))
8493 tree const1 = TREE_OPERAND (arg0, 1);
8495 tree variable = TREE_OPERAND (arg0, 0);
8498 lhs_add = TREE_CODE (arg0) != PLUS_EXPR;
8500 lhs = fold_build2 (lhs_add ? PLUS_EXPR : MINUS_EXPR,
8501 TREE_TYPE (arg1), const2, const1);
8503 /* If the constant operation overflowed this can be
8504 simplified as a comparison against INT_MAX/INT_MIN. */
8505 if (TREE_CODE (lhs) == INTEGER_CST
8506 && TREE_OVERFLOW (lhs))
8508 int const1_sgn = tree_int_cst_sgn (const1);
8509 enum tree_code code2 = code;
8511 /* Get the sign of the constant on the lhs if the
8512 operation were VARIABLE + CONST1. */
8513 if (TREE_CODE (arg0) == MINUS_EXPR)
8514 const1_sgn = -const1_sgn;
8516 /* The sign of the constant determines if we overflowed
8517 INT_MAX (const1_sgn == -1) or INT_MIN (const1_sgn == 1).
8518 Canonicalize to the INT_MIN overflow by swapping the comparison
8520 if (const1_sgn == -1)
8521 code2 = swap_tree_comparison (code);
8523 /* We now can look at the canonicalized case
8524 VARIABLE + 1 CODE2 INT_MIN
8525 and decide on the result. */
8526 if (code2 == LT_EXPR
8528 || code2 == EQ_EXPR)
8529 return omit_one_operand (type, boolean_false_node, variable);
8530 else if (code2 == NE_EXPR
8532 || code2 == GT_EXPR)
8533 return omit_one_operand (type, boolean_true_node, variable);
8536 if (TREE_CODE (lhs) == TREE_CODE (arg1)
8537 && (TREE_CODE (lhs) != INTEGER_CST
8538 || !TREE_OVERFLOW (lhs)))
8540 fold_overflow_warning (("assuming signed overflow does not occur "
8541 "when changing X +- C1 cmp C2 to "
8543 WARN_STRICT_OVERFLOW_COMPARISON);
8544 return fold_build2 (code, type, variable, lhs);
8548 /* For comparisons of pointers we can decompose it to a compile time
8549 comparison of the base objects and the offsets into the object.
8550 This requires at least one operand being an ADDR_EXPR or a
8551 POINTER_PLUS_EXPR to do more than the operand_equal_p test below. */
8552 if (POINTER_TYPE_P (TREE_TYPE (arg0))
8553 && (TREE_CODE (arg0) == ADDR_EXPR
8554 || TREE_CODE (arg1) == ADDR_EXPR
8555 || TREE_CODE (arg0) == POINTER_PLUS_EXPR
8556 || TREE_CODE (arg1) == POINTER_PLUS_EXPR))
8558 tree base0, base1, offset0 = NULL_TREE, offset1 = NULL_TREE;
8559 HOST_WIDE_INT bitsize, bitpos0 = 0, bitpos1 = 0;
8560 enum machine_mode mode;
8561 int volatilep, unsignedp;
8562 bool indirect_base0 = false, indirect_base1 = false;
8564 /* Get base and offset for the access. Strip ADDR_EXPR for
8565 get_inner_reference, but put it back by stripping INDIRECT_REF
8566 off the base object if possible. indirect_baseN will be true
8567 if baseN is not an address but refers to the object itself. */
8569 if (TREE_CODE (arg0) == ADDR_EXPR)
8571 base0 = get_inner_reference (TREE_OPERAND (arg0, 0),
8572 &bitsize, &bitpos0, &offset0, &mode,
8573 &unsignedp, &volatilep, false);
8574 if (TREE_CODE (base0) == INDIRECT_REF)
8575 base0 = TREE_OPERAND (base0, 0);
8577 indirect_base0 = true;
8579 else if (TREE_CODE (arg0) == POINTER_PLUS_EXPR)
8581 base0 = TREE_OPERAND (arg0, 0);
8582 offset0 = TREE_OPERAND (arg0, 1);
8586 if (TREE_CODE (arg1) == ADDR_EXPR)
8588 base1 = get_inner_reference (TREE_OPERAND (arg1, 0),
8589 &bitsize, &bitpos1, &offset1, &mode,
8590 &unsignedp, &volatilep, false);
8591 if (TREE_CODE (base1) == INDIRECT_REF)
8592 base1 = TREE_OPERAND (base1, 0);
8594 indirect_base1 = true;
8596 else if (TREE_CODE (arg1) == POINTER_PLUS_EXPR)
8598 base1 = TREE_OPERAND (arg1, 0);
8599 offset1 = TREE_OPERAND (arg1, 1);
8602 /* If we have equivalent bases we might be able to simplify. */
8603 if (indirect_base0 == indirect_base1
8604 && operand_equal_p (base0, base1, 0))
8606 /* We can fold this expression to a constant if the non-constant
8607 offset parts are equal. */
8608 if ((offset0 == offset1
8609 || (offset0 && offset1
8610 && operand_equal_p (offset0, offset1, 0)))
8613 || POINTER_TYPE_OVERFLOW_UNDEFINED))
8618 && bitpos0 != bitpos1
8619 && (pointer_may_wrap_p (base0, offset0, bitpos0)
8620 || pointer_may_wrap_p (base1, offset1, bitpos1)))
8621 fold_overflow_warning (("assuming pointer wraparound does not "
8622 "occur when comparing P +- C1 with "
8624 WARN_STRICT_OVERFLOW_CONDITIONAL);
8629 return build_int_cst (boolean_type_node, bitpos0 == bitpos1);
8631 return build_int_cst (boolean_type_node, bitpos0 != bitpos1);
8633 return build_int_cst (boolean_type_node, bitpos0 < bitpos1);
8635 return build_int_cst (boolean_type_node, bitpos0 <= bitpos1);
8637 return build_int_cst (boolean_type_node, bitpos0 >= bitpos1);
8639 return build_int_cst (boolean_type_node, bitpos0 > bitpos1);
8643 /* We can simplify the comparison to a comparison of the variable
8644 offset parts if the constant offset parts are equal.
8645 Be careful to use signed size type here because otherwise we
8646 mess with array offsets in the wrong way. This is possible
8647 because pointer arithmetic is restricted to retain within an
8648 object and overflow on pointer differences is undefined as of
8649 6.5.6/8 and /9 with respect to the signed ptrdiff_t. */
8650 else if (bitpos0 == bitpos1
8651 && ((code == EQ_EXPR || code == NE_EXPR)
8652 || POINTER_TYPE_OVERFLOW_UNDEFINED))
8654 tree signed_size_type_node;
8655 signed_size_type_node = signed_type_for (size_type_node);
8657 /* By converting to signed size type we cover middle-end pointer
8658 arithmetic which operates on unsigned pointer types of size
8659 type size and ARRAY_REF offsets which are properly sign or
8660 zero extended from their type in case it is narrower than
8662 if (offset0 == NULL_TREE)
8663 offset0 = build_int_cst (signed_size_type_node, 0);
8665 offset0 = fold_convert (signed_size_type_node, offset0);
8666 if (offset1 == NULL_TREE)
8667 offset1 = build_int_cst (signed_size_type_node, 0);
8669 offset1 = fold_convert (signed_size_type_node, offset1);
8673 && (pointer_may_wrap_p (base0, offset0, bitpos0)
8674 || pointer_may_wrap_p (base1, offset1, bitpos1)))
8675 fold_overflow_warning (("assuming pointer wraparound does not "
8676 "occur when comparing P +- C1 with "
8678 WARN_STRICT_OVERFLOW_COMPARISON);
8680 return fold_build2 (code, type, offset0, offset1);
8683 /* For non-equal bases we can simplify if they are addresses
8684 of local binding decls or constants. */
8685 else if (indirect_base0 && indirect_base1
8686 /* We know that !operand_equal_p (base0, base1, 0)
8687 because the if condition was false. But make
8688 sure two decls are not the same. */
8690 && TREE_CODE (arg0) == ADDR_EXPR
8691 && TREE_CODE (arg1) == ADDR_EXPR
8692 && (((TREE_CODE (base0) == VAR_DECL
8693 || TREE_CODE (base0) == PARM_DECL)
8694 && (targetm.binds_local_p (base0)
8695 || CONSTANT_CLASS_P (base1)))
8696 || CONSTANT_CLASS_P (base0))
8697 && (((TREE_CODE (base1) == VAR_DECL
8698 || TREE_CODE (base1) == PARM_DECL)
8699 && (targetm.binds_local_p (base1)
8700 || CONSTANT_CLASS_P (base0)))
8701 || CONSTANT_CLASS_P (base1)))
8703 if (code == EQ_EXPR)
8704 return omit_two_operands (type, boolean_false_node, arg0, arg1);
8705 else if (code == NE_EXPR)
8706 return omit_two_operands (type, boolean_true_node, arg0, arg1);
8708 /* For equal offsets we can simplify to a comparison of the
8710 else if (bitpos0 == bitpos1
8712 ? base0 != TREE_OPERAND (arg0, 0) : base0 != arg0)
8714 ? base1 != TREE_OPERAND (arg1, 0) : base1 != arg1)
8715 && ((offset0 == offset1)
8716 || (offset0 && offset1
8717 && operand_equal_p (offset0, offset1, 0))))
8720 base0 = fold_addr_expr (base0);
8722 base1 = fold_addr_expr (base1);
8723 return fold_build2 (code, type, base0, base1);
8727 /* Transform comparisons of the form X +- C1 CMP Y +- C2 to
8728 X CMP Y +- C2 +- C1 for signed X, Y. This is valid if
8729 the resulting offset is smaller in absolute value than the
8731 if (TYPE_OVERFLOW_UNDEFINED (TREE_TYPE (arg0))
8732 && (TREE_CODE (arg0) == PLUS_EXPR || TREE_CODE (arg0) == MINUS_EXPR)
8733 && (TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST
8734 && !TREE_OVERFLOW (TREE_OPERAND (arg0, 1)))
8735 && (TREE_CODE (arg1) == PLUS_EXPR || TREE_CODE (arg1) == MINUS_EXPR)
8736 && (TREE_CODE (TREE_OPERAND (arg1, 1)) == INTEGER_CST
8737 && !TREE_OVERFLOW (TREE_OPERAND (arg1, 1))))
8739 tree const1 = TREE_OPERAND (arg0, 1);
8740 tree const2 = TREE_OPERAND (arg1, 1);
8741 tree variable1 = TREE_OPERAND (arg0, 0);
8742 tree variable2 = TREE_OPERAND (arg1, 0);
8744 const char * const warnmsg = G_("assuming signed overflow does not "
8745 "occur when combining constants around "
8748 /* Put the constant on the side where it doesn't overflow and is
8749 of lower absolute value than before. */
8750 cst = int_const_binop (TREE_CODE (arg0) == TREE_CODE (arg1)
8751 ? MINUS_EXPR : PLUS_EXPR,
8753 if (!TREE_OVERFLOW (cst)
8754 && tree_int_cst_compare (const2, cst) == tree_int_cst_sgn (const2))
8756 fold_overflow_warning (warnmsg, WARN_STRICT_OVERFLOW_COMPARISON);
8757 return fold_build2 (code, type,
8759 fold_build2 (TREE_CODE (arg1), TREE_TYPE (arg1),
8763 cst = int_const_binop (TREE_CODE (arg0) == TREE_CODE (arg1)
8764 ? MINUS_EXPR : PLUS_EXPR,
8766 if (!TREE_OVERFLOW (cst)
8767 && tree_int_cst_compare (const1, cst) == tree_int_cst_sgn (const1))
8769 fold_overflow_warning (warnmsg, WARN_STRICT_OVERFLOW_COMPARISON);
8770 return fold_build2 (code, type,
8771 fold_build2 (TREE_CODE (arg0), TREE_TYPE (arg0),
8777 /* Transform comparisons of the form X * C1 CMP 0 to X CMP 0 in the
8778 signed arithmetic case. That form is created by the compiler
8779 often enough for folding it to be of value. One example is in
8780 computing loop trip counts after Operator Strength Reduction. */
8781 if (TYPE_OVERFLOW_UNDEFINED (TREE_TYPE (arg0))
8782 && TREE_CODE (arg0) == MULT_EXPR
8783 && (TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST
8784 && !TREE_OVERFLOW (TREE_OPERAND (arg0, 1)))
8785 && integer_zerop (arg1))
8787 tree const1 = TREE_OPERAND (arg0, 1);
8788 tree const2 = arg1; /* zero */
8789 tree variable1 = TREE_OPERAND (arg0, 0);
8790 enum tree_code cmp_code = code;
8792 gcc_assert (!integer_zerop (const1));
8794 fold_overflow_warning (("assuming signed overflow does not occur when "
8795 "eliminating multiplication in comparison "
8797 WARN_STRICT_OVERFLOW_COMPARISON);
8799 /* If const1 is negative we swap the sense of the comparison. */
8800 if (tree_int_cst_sgn (const1) < 0)
8801 cmp_code = swap_tree_comparison (cmp_code);
8803 return fold_build2 (cmp_code, type, variable1, const2);
8806 tem = maybe_canonicalize_comparison (code, type, op0, op1);
8810 if (FLOAT_TYPE_P (TREE_TYPE (arg0)))
8812 tree targ0 = strip_float_extensions (arg0);
8813 tree targ1 = strip_float_extensions (arg1);
8814 tree newtype = TREE_TYPE (targ0);
8816 if (TYPE_PRECISION (TREE_TYPE (targ1)) > TYPE_PRECISION (newtype))
8817 newtype = TREE_TYPE (targ1);
8819 /* Fold (double)float1 CMP (double)float2 into float1 CMP float2. */
8820 if (TYPE_PRECISION (newtype) < TYPE_PRECISION (TREE_TYPE (arg0)))
8821 return fold_build2 (code, type, fold_convert (newtype, targ0),
8822 fold_convert (newtype, targ1));
8824 /* (-a) CMP (-b) -> b CMP a */
8825 if (TREE_CODE (arg0) == NEGATE_EXPR
8826 && TREE_CODE (arg1) == NEGATE_EXPR)
8827 return fold_build2 (code, type, TREE_OPERAND (arg1, 0),
8828 TREE_OPERAND (arg0, 0));
8830 if (TREE_CODE (arg1) == REAL_CST)
8832 REAL_VALUE_TYPE cst;
8833 cst = TREE_REAL_CST (arg1);
8835 /* (-a) CMP CST -> a swap(CMP) (-CST) */
8836 if (TREE_CODE (arg0) == NEGATE_EXPR)
8837 return fold_build2 (swap_tree_comparison (code), type,
8838 TREE_OPERAND (arg0, 0),
8839 build_real (TREE_TYPE (arg1),
8840 REAL_VALUE_NEGATE (cst)));
8842 /* IEEE doesn't distinguish +0 and -0 in comparisons. */
8843 /* a CMP (-0) -> a CMP 0 */
8844 if (REAL_VALUE_MINUS_ZERO (cst))
8845 return fold_build2 (code, type, arg0,
8846 build_real (TREE_TYPE (arg1), dconst0));
8848 /* x != NaN is always true, other ops are always false. */
8849 if (REAL_VALUE_ISNAN (cst)
8850 && ! HONOR_SNANS (TYPE_MODE (TREE_TYPE (arg1))))
8852 tem = (code == NE_EXPR) ? integer_one_node : integer_zero_node;
8853 return omit_one_operand (type, tem, arg0);
8856 /* Fold comparisons against infinity. */
8857 if (REAL_VALUE_ISINF (cst))
8859 tem = fold_inf_compare (code, type, arg0, arg1);
8860 if (tem != NULL_TREE)
8865 /* If this is a comparison of a real constant with a PLUS_EXPR
8866 or a MINUS_EXPR of a real constant, we can convert it into a
8867 comparison with a revised real constant as long as no overflow
8868 occurs when unsafe_math_optimizations are enabled. */
8869 if (flag_unsafe_math_optimizations
8870 && TREE_CODE (arg1) == REAL_CST
8871 && (TREE_CODE (arg0) == PLUS_EXPR
8872 || TREE_CODE (arg0) == MINUS_EXPR)
8873 && TREE_CODE (TREE_OPERAND (arg0, 1)) == REAL_CST
8874 && 0 != (tem = const_binop (TREE_CODE (arg0) == PLUS_EXPR
8875 ? MINUS_EXPR : PLUS_EXPR,
8876 arg1, TREE_OPERAND (arg0, 1), 0))
8877 && !TREE_OVERFLOW (tem))
8878 return fold_build2 (code, type, TREE_OPERAND (arg0, 0), tem);
8880 /* Likewise, we can simplify a comparison of a real constant with
8881 a MINUS_EXPR whose first operand is also a real constant, i.e.
8882 (c1 - x) < c2 becomes x > c1-c2. Reordering is allowed on
8883 floating-point types only if -fassociative-math is set. */
8884 if (flag_associative_math
8885 && TREE_CODE (arg1) == REAL_CST
8886 && TREE_CODE (arg0) == MINUS_EXPR
8887 && TREE_CODE (TREE_OPERAND (arg0, 0)) == REAL_CST
8888 && 0 != (tem = const_binop (MINUS_EXPR, TREE_OPERAND (arg0, 0),
8890 && !TREE_OVERFLOW (tem))
8891 return fold_build2 (swap_tree_comparison (code), type,
8892 TREE_OPERAND (arg0, 1), tem);
8894 /* Fold comparisons against built-in math functions. */
8895 if (TREE_CODE (arg1) == REAL_CST
8896 && flag_unsafe_math_optimizations
8897 && ! flag_errno_math)
8899 enum built_in_function fcode = builtin_mathfn_code (arg0);
8901 if (fcode != END_BUILTINS)
8903 tem = fold_mathfn_compare (fcode, code, type, arg0, arg1);
8904 if (tem != NULL_TREE)
8910 if (TREE_CODE (TREE_TYPE (arg0)) == INTEGER_TYPE
8911 && (TREE_CODE (arg0) == NOP_EXPR
8912 || TREE_CODE (arg0) == CONVERT_EXPR))
8914 /* If we are widening one operand of an integer comparison,
8915 see if the other operand is similarly being widened. Perhaps we
8916 can do the comparison in the narrower type. */
8917 tem = fold_widened_comparison (code, type, arg0, arg1);
8921 /* Or if we are changing signedness. */
8922 tem = fold_sign_changed_comparison (code, type, arg0, arg1);
8927 /* If this is comparing a constant with a MIN_EXPR or a MAX_EXPR of a
8928 constant, we can simplify it. */
8929 if (TREE_CODE (arg1) == INTEGER_CST
8930 && (TREE_CODE (arg0) == MIN_EXPR
8931 || TREE_CODE (arg0) == MAX_EXPR)
8932 && TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST)
8934 tem = optimize_minmax_comparison (code, type, op0, op1);
8939 /* Simplify comparison of something with itself. (For IEEE
8940 floating-point, we can only do some of these simplifications.) */
8941 if (operand_equal_p (arg0, arg1, 0))
8946 if (! FLOAT_TYPE_P (TREE_TYPE (arg0))
8947 || ! HONOR_NANS (TYPE_MODE (TREE_TYPE (arg0))))
8948 return constant_boolean_node (1, type);
8953 if (! FLOAT_TYPE_P (TREE_TYPE (arg0))
8954 || ! HONOR_NANS (TYPE_MODE (TREE_TYPE (arg0))))
8955 return constant_boolean_node (1, type);
8956 return fold_build2 (EQ_EXPR, type, arg0, arg1);
8959 /* For NE, we can only do this simplification if integer
8960 or we don't honor IEEE floating point NaNs. */
8961 if (FLOAT_TYPE_P (TREE_TYPE (arg0))
8962 && HONOR_NANS (TYPE_MODE (TREE_TYPE (arg0))))
8964 /* ... fall through ... */
8967 return constant_boolean_node (0, type);
8973 /* If we are comparing an expression that just has comparisons
8974 of two integer values, arithmetic expressions of those comparisons,
8975 and constants, we can simplify it. There are only three cases
8976 to check: the two values can either be equal, the first can be
8977 greater, or the second can be greater. Fold the expression for
8978 those three values. Since each value must be 0 or 1, we have
8979 eight possibilities, each of which corresponds to the constant 0
8980 or 1 or one of the six possible comparisons.
8982 This handles common cases like (a > b) == 0 but also handles
8983 expressions like ((x > y) - (y > x)) > 0, which supposedly
8984 occur in macroized code. */
8986 if (TREE_CODE (arg1) == INTEGER_CST && TREE_CODE (arg0) != INTEGER_CST)
8988 tree cval1 = 0, cval2 = 0;
8991 if (twoval_comparison_p (arg0, &cval1, &cval2, &save_p)
8992 /* Don't handle degenerate cases here; they should already
8993 have been handled anyway. */
8994 && cval1 != 0 && cval2 != 0
8995 && ! (TREE_CONSTANT (cval1) && TREE_CONSTANT (cval2))
8996 && TREE_TYPE (cval1) == TREE_TYPE (cval2)
8997 && INTEGRAL_TYPE_P (TREE_TYPE (cval1))
8998 && TYPE_MAX_VALUE (TREE_TYPE (cval1))
8999 && TYPE_MAX_VALUE (TREE_TYPE (cval2))
9000 && ! operand_equal_p (TYPE_MIN_VALUE (TREE_TYPE (cval1)),
9001 TYPE_MAX_VALUE (TREE_TYPE (cval2)), 0))
9003 tree maxval = TYPE_MAX_VALUE (TREE_TYPE (cval1));
9004 tree minval = TYPE_MIN_VALUE (TREE_TYPE (cval1));
9006 /* We can't just pass T to eval_subst in case cval1 or cval2
9007 was the same as ARG1. */
9010 = fold_build2 (code, type,
9011 eval_subst (arg0, cval1, maxval,
9015 = fold_build2 (code, type,
9016 eval_subst (arg0, cval1, maxval,
9020 = fold_build2 (code, type,
9021 eval_subst (arg0, cval1, minval,
9025 /* All three of these results should be 0 or 1. Confirm they are.
9026 Then use those values to select the proper code to use. */
9028 if (TREE_CODE (high_result) == INTEGER_CST
9029 && TREE_CODE (equal_result) == INTEGER_CST
9030 && TREE_CODE (low_result) == INTEGER_CST)
9032 /* Make a 3-bit mask with the high-order bit being the
9033 value for `>', the next for '=', and the low for '<'. */
9034 switch ((integer_onep (high_result) * 4)
9035 + (integer_onep (equal_result) * 2)
9036 + integer_onep (low_result))
9040 return omit_one_operand (type, integer_zero_node, arg0);
9061 return omit_one_operand (type, integer_one_node, arg0);
9065 return save_expr (build2 (code, type, cval1, cval2));
9066 return fold_build2 (code, type, cval1, cval2);
9071 /* We can fold X/C1 op C2 where C1 and C2 are integer constants
9072 into a single range test. */
9073 if ((TREE_CODE (arg0) == TRUNC_DIV_EXPR
9074 || TREE_CODE (arg0) == EXACT_DIV_EXPR)
9075 && TREE_CODE (arg1) == INTEGER_CST
9076 && TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST
9077 && !integer_zerop (TREE_OPERAND (arg0, 1))
9078 && !TREE_OVERFLOW (TREE_OPERAND (arg0, 1))
9079 && !TREE_OVERFLOW (arg1))
9081 tem = fold_div_compare (code, type, arg0, arg1);
9082 if (tem != NULL_TREE)
9086 /* Fold ~X op ~Y as Y op X. */
9087 if (TREE_CODE (arg0) == BIT_NOT_EXPR
9088 && TREE_CODE (arg1) == BIT_NOT_EXPR)
9090 tree cmp_type = TREE_TYPE (TREE_OPERAND (arg0, 0));
9091 return fold_build2 (code, type,
9092 fold_convert (cmp_type, TREE_OPERAND (arg1, 0)),
9093 TREE_OPERAND (arg0, 0));
9096 /* Fold ~X op C as X op' ~C, where op' is the swapped comparison. */
9097 if (TREE_CODE (arg0) == BIT_NOT_EXPR
9098 && TREE_CODE (arg1) == INTEGER_CST)
9100 tree cmp_type = TREE_TYPE (TREE_OPERAND (arg0, 0));
9101 return fold_build2 (swap_tree_comparison (code), type,
9102 TREE_OPERAND (arg0, 0),
9103 fold_build1 (BIT_NOT_EXPR, cmp_type,
9104 fold_convert (cmp_type, arg1)));
9111 /* Subroutine of fold_binary. Optimize complex multiplications of the
9112 form z * conj(z), as pow(realpart(z),2) + pow(imagpart(z),2). The
9113 argument EXPR represents the expression "z" of type TYPE. */
9116 fold_mult_zconjz (tree type, tree expr)
9118 tree itype = TREE_TYPE (type);
9119 tree rpart, ipart, tem;
9121 if (TREE_CODE (expr) == COMPLEX_EXPR)
9123 rpart = TREE_OPERAND (expr, 0);
9124 ipart = TREE_OPERAND (expr, 1);
9126 else if (TREE_CODE (expr) == COMPLEX_CST)
9128 rpart = TREE_REALPART (expr);
9129 ipart = TREE_IMAGPART (expr);
9133 expr = save_expr (expr);
9134 rpart = fold_build1 (REALPART_EXPR, itype, expr);
9135 ipart = fold_build1 (IMAGPART_EXPR, itype, expr);
9138 rpart = save_expr (rpart);
9139 ipart = save_expr (ipart);
9140 tem = fold_build2 (PLUS_EXPR, itype,
9141 fold_build2 (MULT_EXPR, itype, rpart, rpart),
9142 fold_build2 (MULT_EXPR, itype, ipart, ipart));
9143 return fold_build2 (COMPLEX_EXPR, type, tem,
9144 fold_convert (itype, integer_zero_node));
9148 /* Subroutine of fold_binary. If P is the value of EXPR, computes
9149 power-of-two M and (arbitrary) N such that M divides (P-N). This condition
9150 guarantees that P and N have the same least significant log2(M) bits.
9151 N is not otherwise constrained. In particular, N is not normalized to
9152 0 <= N < M as is common. In general, the precise value of P is unknown.
9153 M is chosen as large as possible such that constant N can be determined.
9155 Returns M and sets *RESIDUE to N. */
9157 static unsigned HOST_WIDE_INT
9158 get_pointer_modulus_and_residue (tree expr, unsigned HOST_WIDE_INT *residue)
9160 enum tree_code code;
9164 code = TREE_CODE (expr);
9165 if (code == ADDR_EXPR)
9167 expr = TREE_OPERAND (expr, 0);
9168 if (handled_component_p (expr))
9170 HOST_WIDE_INT bitsize, bitpos;
9172 enum machine_mode mode;
9173 int unsignedp, volatilep;
9175 expr = get_inner_reference (expr, &bitsize, &bitpos, &offset,
9176 &mode, &unsignedp, &volatilep, false);
9177 *residue = bitpos / BITS_PER_UNIT;
9180 if (TREE_CODE (offset) == INTEGER_CST)
9181 *residue += TREE_INT_CST_LOW (offset);
9183 /* We don't handle more complicated offset expressions. */
9188 if (DECL_P (expr) && TREE_CODE (expr) != FUNCTION_DECL)
9189 return DECL_ALIGN_UNIT (expr);
9191 else if (code == POINTER_PLUS_EXPR)
9194 unsigned HOST_WIDE_INT modulus;
9195 enum tree_code inner_code;
9197 op0 = TREE_OPERAND (expr, 0);
9199 modulus = get_pointer_modulus_and_residue (op0, residue);
9201 op1 = TREE_OPERAND (expr, 1);
9203 inner_code = TREE_CODE (op1);
9204 if (inner_code == INTEGER_CST)
9206 *residue += TREE_INT_CST_LOW (op1);
9209 else if (inner_code == MULT_EXPR)
9211 op1 = TREE_OPERAND (op1, 1);
9212 if (TREE_CODE (op1) == INTEGER_CST)
9214 unsigned HOST_WIDE_INT align;
9216 /* Compute the greatest power-of-2 divisor of op1. */
9217 align = TREE_INT_CST_LOW (op1);
9220 /* If align is non-zero and less than *modulus, replace
9221 *modulus with align., If align is 0, then either op1 is 0
9222 or the greatest power-of-2 divisor of op1 doesn't fit in an
9223 unsigned HOST_WIDE_INT. In either case, no additional
9224 constraint is imposed. */
9226 modulus = MIN (modulus, align);
9233 /* If we get here, we were unable to determine anything useful about the
9239 /* Fold a binary expression of code CODE and type TYPE with operands
9240 OP0 and OP1. Return the folded expression if folding is
9241 successful. Otherwise, return NULL_TREE. */
9244 fold_binary (enum tree_code code, tree type, tree op0, tree op1)
9246 enum tree_code_class kind = TREE_CODE_CLASS (code);
9247 tree arg0, arg1, tem;
9248 tree t1 = NULL_TREE;
9249 bool strict_overflow_p;
9251 gcc_assert ((IS_EXPR_CODE_CLASS (kind)
9252 || IS_GIMPLE_STMT_CODE_CLASS (kind))
9253 && TREE_CODE_LENGTH (code) == 2
9255 && op1 != NULL_TREE);
9260 /* Strip any conversions that don't change the mode. This is
9261 safe for every expression, except for a comparison expression
9262 because its signedness is derived from its operands. So, in
9263 the latter case, only strip conversions that don't change the
9266 Note that this is done as an internal manipulation within the
9267 constant folder, in order to find the simplest representation
9268 of the arguments so that their form can be studied. In any
9269 cases, the appropriate type conversions should be put back in
9270 the tree that will get out of the constant folder. */
9272 if (kind == tcc_comparison)
9274 STRIP_SIGN_NOPS (arg0);
9275 STRIP_SIGN_NOPS (arg1);
9283 /* Note that TREE_CONSTANT isn't enough: static var addresses are
9284 constant but we can't do arithmetic on them. */
9285 if ((TREE_CODE (arg0) == INTEGER_CST && TREE_CODE (arg1) == INTEGER_CST)
9286 || (TREE_CODE (arg0) == REAL_CST && TREE_CODE (arg1) == REAL_CST)
9287 || (TREE_CODE (arg0) == FIXED_CST && TREE_CODE (arg1) == FIXED_CST)
9288 || (TREE_CODE (arg0) == FIXED_CST && TREE_CODE (arg1) == INTEGER_CST)
9289 || (TREE_CODE (arg0) == COMPLEX_CST && TREE_CODE (arg1) == COMPLEX_CST)
9290 || (TREE_CODE (arg0) == VECTOR_CST && TREE_CODE (arg1) == VECTOR_CST))
9292 if (kind == tcc_binary)
9294 /* Make sure type and arg0 have the same saturating flag. */
9295 gcc_assert (TYPE_SATURATING (type)
9296 == TYPE_SATURATING (TREE_TYPE (arg0)));
9297 tem = const_binop (code, arg0, arg1, 0);
9299 else if (kind == tcc_comparison)
9300 tem = fold_relational_const (code, type, arg0, arg1);
9304 if (tem != NULL_TREE)
9306 if (TREE_TYPE (tem) != type)
9307 tem = fold_convert (type, tem);
9312 /* If this is a commutative operation, and ARG0 is a constant, move it
9313 to ARG1 to reduce the number of tests below. */
9314 if (commutative_tree_code (code)
9315 && tree_swap_operands_p (arg0, arg1, true))
9316 return fold_build2 (code, type, op1, op0);
9318 /* ARG0 is the first operand of EXPR, and ARG1 is the second operand.
9320 First check for cases where an arithmetic operation is applied to a
9321 compound, conditional, or comparison operation. Push the arithmetic
9322 operation inside the compound or conditional to see if any folding
9323 can then be done. Convert comparison to conditional for this purpose.
9324 The also optimizes non-constant cases that used to be done in
9327 Before we do that, see if this is a BIT_AND_EXPR or a BIT_IOR_EXPR,
9328 one of the operands is a comparison and the other is a comparison, a
9329 BIT_AND_EXPR with the constant 1, or a truth value. In that case, the
9330 code below would make the expression more complex. Change it to a
9331 TRUTH_{AND,OR}_EXPR. Likewise, convert a similar NE_EXPR to
9332 TRUTH_XOR_EXPR and an EQ_EXPR to the inversion of a TRUTH_XOR_EXPR. */
9334 if ((code == BIT_AND_EXPR || code == BIT_IOR_EXPR
9335 || code == EQ_EXPR || code == NE_EXPR)
9336 && ((truth_value_p (TREE_CODE (arg0))
9337 && (truth_value_p (TREE_CODE (arg1))
9338 || (TREE_CODE (arg1) == BIT_AND_EXPR
9339 && integer_onep (TREE_OPERAND (arg1, 1)))))
9340 || (truth_value_p (TREE_CODE (arg1))
9341 && (truth_value_p (TREE_CODE (arg0))
9342 || (TREE_CODE (arg0) == BIT_AND_EXPR
9343 && integer_onep (TREE_OPERAND (arg0, 1)))))))
9345 tem = fold_build2 (code == BIT_AND_EXPR ? TRUTH_AND_EXPR
9346 : code == BIT_IOR_EXPR ? TRUTH_OR_EXPR
9349 fold_convert (boolean_type_node, arg0),
9350 fold_convert (boolean_type_node, arg1));
9352 if (code == EQ_EXPR)
9353 tem = invert_truthvalue (tem);
9355 return fold_convert (type, tem);
9358 if (TREE_CODE_CLASS (code) == tcc_binary
9359 || TREE_CODE_CLASS (code) == tcc_comparison)
9361 if (TREE_CODE (arg0) == COMPOUND_EXPR)
9362 return build2 (COMPOUND_EXPR, type, TREE_OPERAND (arg0, 0),
9363 fold_build2 (code, type,
9364 fold_convert (TREE_TYPE (op0),
9365 TREE_OPERAND (arg0, 1)),
9367 if (TREE_CODE (arg1) == COMPOUND_EXPR
9368 && reorder_operands_p (arg0, TREE_OPERAND (arg1, 0)))
9369 return build2 (COMPOUND_EXPR, type, TREE_OPERAND (arg1, 0),
9370 fold_build2 (code, type, op0,
9371 fold_convert (TREE_TYPE (op1),
9372 TREE_OPERAND (arg1, 1))));
9374 if (TREE_CODE (arg0) == COND_EXPR || COMPARISON_CLASS_P (arg0))
9376 tem = fold_binary_op_with_conditional_arg (code, type, op0, op1,
9378 /*cond_first_p=*/1);
9379 if (tem != NULL_TREE)
9383 if (TREE_CODE (arg1) == COND_EXPR || COMPARISON_CLASS_P (arg1))
9385 tem = fold_binary_op_with_conditional_arg (code, type, op0, op1,
9387 /*cond_first_p=*/0);
9388 if (tem != NULL_TREE)
9395 case POINTER_PLUS_EXPR:
9396 /* 0 +p index -> (type)index */
9397 if (integer_zerop (arg0))
9398 return non_lvalue (fold_convert (type, arg1));
9400 /* PTR +p 0 -> PTR */
9401 if (integer_zerop (arg1))
9402 return non_lvalue (fold_convert (type, arg0));
9404 /* INT +p INT -> (PTR)(INT + INT). Stripping types allows for this. */
9405 if (INTEGRAL_TYPE_P (TREE_TYPE (arg1))
9406 && INTEGRAL_TYPE_P (TREE_TYPE (arg0)))
9407 return fold_convert (type, fold_build2 (PLUS_EXPR, sizetype,
9408 fold_convert (sizetype, arg1),
9409 fold_convert (sizetype, arg0)));
9411 /* index +p PTR -> PTR +p index */
9412 if (POINTER_TYPE_P (TREE_TYPE (arg1))
9413 && INTEGRAL_TYPE_P (TREE_TYPE (arg0)))
9414 return fold_build2 (POINTER_PLUS_EXPR, type,
9415 fold_convert (type, arg1),
9416 fold_convert (sizetype, arg0));
9418 /* (PTR +p B) +p A -> PTR +p (B + A) */
9419 if (TREE_CODE (arg0) == POINTER_PLUS_EXPR)
9422 tree arg01 = fold_convert (sizetype, TREE_OPERAND (arg0, 1));
9423 tree arg00 = TREE_OPERAND (arg0, 0);
9424 inner = fold_build2 (PLUS_EXPR, sizetype,
9425 arg01, fold_convert (sizetype, arg1));
9426 return fold_convert (type,
9427 fold_build2 (POINTER_PLUS_EXPR,
9428 TREE_TYPE (arg00), arg00, inner));
9431 /* PTR_CST +p CST -> CST1 */
9432 if (TREE_CODE (arg0) == INTEGER_CST && TREE_CODE (arg1) == INTEGER_CST)
9433 return fold_build2 (PLUS_EXPR, type, arg0, fold_convert (type, arg1));
9435 /* Try replacing &a[i1] +p c * i2 with &a[i1 + i2], if c is step
9436 of the array. Loop optimizer sometimes produce this type of
9438 if (TREE_CODE (arg0) == ADDR_EXPR)
9440 tem = try_move_mult_to_index (arg0, fold_convert (sizetype, arg1));
9442 return fold_convert (type, tem);
9448 /* PTR + INT -> (INT)(PTR p+ INT) */
9449 if (POINTER_TYPE_P (TREE_TYPE (arg0))
9450 && INTEGRAL_TYPE_P (TREE_TYPE (arg1)))
9451 return fold_convert (type, fold_build2 (POINTER_PLUS_EXPR,
9454 fold_convert (sizetype, arg1)));
9455 /* INT + PTR -> (INT)(PTR p+ INT) */
9456 if (POINTER_TYPE_P (TREE_TYPE (arg1))
9457 && INTEGRAL_TYPE_P (TREE_TYPE (arg0)))
9458 return fold_convert (type, fold_build2 (POINTER_PLUS_EXPR,
9461 fold_convert (sizetype, arg0)));
9462 /* A + (-B) -> A - B */
9463 if (TREE_CODE (arg1) == NEGATE_EXPR)
9464 return fold_build2 (MINUS_EXPR, type,
9465 fold_convert (type, arg0),
9466 fold_convert (type, TREE_OPERAND (arg1, 0)));
9467 /* (-A) + B -> B - A */
9468 if (TREE_CODE (arg0) == NEGATE_EXPR
9469 && reorder_operands_p (TREE_OPERAND (arg0, 0), arg1))
9470 return fold_build2 (MINUS_EXPR, type,
9471 fold_convert (type, arg1),
9472 fold_convert (type, TREE_OPERAND (arg0, 0)));
9474 if (INTEGRAL_TYPE_P (type))
9476 /* Convert ~A + 1 to -A. */
9477 if (TREE_CODE (arg0) == BIT_NOT_EXPR
9478 && integer_onep (arg1))
9479 return fold_build1 (NEGATE_EXPR, type, TREE_OPERAND (arg0, 0));
9482 if (TREE_CODE (arg0) == BIT_NOT_EXPR
9483 && !TYPE_OVERFLOW_TRAPS (type))
9485 tree tem = TREE_OPERAND (arg0, 0);
9488 if (operand_equal_p (tem, arg1, 0))
9490 t1 = build_int_cst_type (type, -1);
9491 return omit_one_operand (type, t1, arg1);
9496 if (TREE_CODE (arg1) == BIT_NOT_EXPR
9497 && !TYPE_OVERFLOW_TRAPS (type))
9499 tree tem = TREE_OPERAND (arg1, 0);
9502 if (operand_equal_p (arg0, tem, 0))
9504 t1 = build_int_cst_type (type, -1);
9505 return omit_one_operand (type, t1, arg0);
9509 /* X + (X / CST) * -CST is X % CST. */
9510 if (TREE_CODE (arg1) == MULT_EXPR
9511 && TREE_CODE (TREE_OPERAND (arg1, 0)) == TRUNC_DIV_EXPR
9512 && operand_equal_p (arg0,
9513 TREE_OPERAND (TREE_OPERAND (arg1, 0), 0), 0))
9515 tree cst0 = TREE_OPERAND (TREE_OPERAND (arg1, 0), 1);
9516 tree cst1 = TREE_OPERAND (arg1, 1);
9517 tree sum = fold_binary (PLUS_EXPR, TREE_TYPE (cst1), cst1, cst0);
9518 if (sum && integer_zerop (sum))
9519 return fold_convert (type,
9520 fold_build2 (TRUNC_MOD_EXPR,
9521 TREE_TYPE (arg0), arg0, cst0));
9525 /* Handle (A1 * C1) + (A2 * C2) with A1, A2 or C1, C2 being the
9526 same or one. Make sure type is not saturating.
9527 fold_plusminus_mult_expr will re-associate. */
9528 if ((TREE_CODE (arg0) == MULT_EXPR
9529 || TREE_CODE (arg1) == MULT_EXPR)
9530 && !TYPE_SATURATING (type)
9531 && (!FLOAT_TYPE_P (type) || flag_associative_math))
9533 tree tem = fold_plusminus_mult_expr (code, type, arg0, arg1);
9538 if (! FLOAT_TYPE_P (type))
9540 if (integer_zerop (arg1))
9541 return non_lvalue (fold_convert (type, arg0));
9543 /* If we are adding two BIT_AND_EXPR's, both of which are and'ing
9544 with a constant, and the two constants have no bits in common,
9545 we should treat this as a BIT_IOR_EXPR since this may produce more
9547 if (TREE_CODE (arg0) == BIT_AND_EXPR
9548 && TREE_CODE (arg1) == BIT_AND_EXPR
9549 && TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST
9550 && TREE_CODE (TREE_OPERAND (arg1, 1)) == INTEGER_CST
9551 && integer_zerop (const_binop (BIT_AND_EXPR,
9552 TREE_OPERAND (arg0, 1),
9553 TREE_OPERAND (arg1, 1), 0)))
9555 code = BIT_IOR_EXPR;
9559 /* Reassociate (plus (plus (mult) (foo)) (mult)) as
9560 (plus (plus (mult) (mult)) (foo)) so that we can
9561 take advantage of the factoring cases below. */
9562 if (((TREE_CODE (arg0) == PLUS_EXPR
9563 || TREE_CODE (arg0) == MINUS_EXPR)
9564 && TREE_CODE (arg1) == MULT_EXPR)
9565 || ((TREE_CODE (arg1) == PLUS_EXPR
9566 || TREE_CODE (arg1) == MINUS_EXPR)
9567 && TREE_CODE (arg0) == MULT_EXPR))
9569 tree parg0, parg1, parg, marg;
9570 enum tree_code pcode;
9572 if (TREE_CODE (arg1) == MULT_EXPR)
9573 parg = arg0, marg = arg1;
9575 parg = arg1, marg = arg0;
9576 pcode = TREE_CODE (parg);
9577 parg0 = TREE_OPERAND (parg, 0);
9578 parg1 = TREE_OPERAND (parg, 1);
9582 if (TREE_CODE (parg0) == MULT_EXPR
9583 && TREE_CODE (parg1) != MULT_EXPR)
9584 return fold_build2 (pcode, type,
9585 fold_build2 (PLUS_EXPR, type,
9586 fold_convert (type, parg0),
9587 fold_convert (type, marg)),
9588 fold_convert (type, parg1));
9589 if (TREE_CODE (parg0) != MULT_EXPR
9590 && TREE_CODE (parg1) == MULT_EXPR)
9591 return fold_build2 (PLUS_EXPR, type,
9592 fold_convert (type, parg0),
9593 fold_build2 (pcode, type,
9594 fold_convert (type, marg),
9601 /* See if ARG1 is zero and X + ARG1 reduces to X. */
9602 if (fold_real_zero_addition_p (TREE_TYPE (arg0), arg1, 0))
9603 return non_lvalue (fold_convert (type, arg0));
9605 /* Likewise if the operands are reversed. */
9606 if (fold_real_zero_addition_p (TREE_TYPE (arg1), arg0, 0))
9607 return non_lvalue (fold_convert (type, arg1));
9609 /* Convert X + -C into X - C. */
9610 if (TREE_CODE (arg1) == REAL_CST
9611 && REAL_VALUE_NEGATIVE (TREE_REAL_CST (arg1)))
9613 tem = fold_negate_const (arg1, type);
9614 if (!TREE_OVERFLOW (arg1) || !flag_trapping_math)
9615 return fold_build2 (MINUS_EXPR, type,
9616 fold_convert (type, arg0),
9617 fold_convert (type, tem));
9620 /* Fold __complex__ ( x, 0 ) + __complex__ ( 0, y )
9621 to __complex__ ( x, y ). This is not the same for SNaNs or
9622 if signed zeros are involved. */
9623 if (!HONOR_SNANS (TYPE_MODE (TREE_TYPE (arg0)))
9624 && !HONOR_SIGNED_ZEROS (TYPE_MODE (TREE_TYPE (arg0)))
9625 && COMPLEX_FLOAT_TYPE_P (TREE_TYPE (arg0)))
9627 tree rtype = TREE_TYPE (TREE_TYPE (arg0));
9628 tree arg0r = fold_unary (REALPART_EXPR, rtype, arg0);
9629 tree arg0i = fold_unary (IMAGPART_EXPR, rtype, arg0);
9630 bool arg0rz = false, arg0iz = false;
9631 if ((arg0r && (arg0rz = real_zerop (arg0r)))
9632 || (arg0i && (arg0iz = real_zerop (arg0i))))
9634 tree arg1r = fold_unary (REALPART_EXPR, rtype, arg1);
9635 tree arg1i = fold_unary (IMAGPART_EXPR, rtype, arg1);
9636 if (arg0rz && arg1i && real_zerop (arg1i))
9638 tree rp = arg1r ? arg1r
9639 : build1 (REALPART_EXPR, rtype, arg1);
9640 tree ip = arg0i ? arg0i
9641 : build1 (IMAGPART_EXPR, rtype, arg0);
9642 return fold_build2 (COMPLEX_EXPR, type, rp, ip);
9644 else if (arg0iz && arg1r && real_zerop (arg1r))
9646 tree rp = arg0r ? arg0r
9647 : build1 (REALPART_EXPR, rtype, arg0);
9648 tree ip = arg1i ? arg1i
9649 : build1 (IMAGPART_EXPR, rtype, arg1);
9650 return fold_build2 (COMPLEX_EXPR, type, rp, ip);
9655 if (flag_unsafe_math_optimizations
9656 && (TREE_CODE (arg0) == RDIV_EXPR || TREE_CODE (arg0) == MULT_EXPR)
9657 && (TREE_CODE (arg1) == RDIV_EXPR || TREE_CODE (arg1) == MULT_EXPR)
9658 && (tem = distribute_real_division (code, type, arg0, arg1)))
9661 /* Convert x+x into x*2.0. */
9662 if (operand_equal_p (arg0, arg1, 0)
9663 && SCALAR_FLOAT_TYPE_P (type))
9664 return fold_build2 (MULT_EXPR, type, arg0,
9665 build_real (type, dconst2));
9667 /* Convert a + (b*c + d*e) into (a + b*c) + d*e.
9668 We associate floats only if the user has specified
9669 -fassociative-math. */
9670 if (flag_associative_math
9671 && TREE_CODE (arg1) == PLUS_EXPR
9672 && TREE_CODE (arg0) != MULT_EXPR)
9674 tree tree10 = TREE_OPERAND (arg1, 0);
9675 tree tree11 = TREE_OPERAND (arg1, 1);
9676 if (TREE_CODE (tree11) == MULT_EXPR
9677 && TREE_CODE (tree10) == MULT_EXPR)
9680 tree0 = fold_build2 (PLUS_EXPR, type, arg0, tree10);
9681 return fold_build2 (PLUS_EXPR, type, tree0, tree11);
9684 /* Convert (b*c + d*e) + a into b*c + (d*e +a).
9685 We associate floats only if the user has specified
9686 -fassociative-math. */
9687 if (flag_associative_math
9688 && TREE_CODE (arg0) == PLUS_EXPR
9689 && TREE_CODE (arg1) != MULT_EXPR)
9691 tree tree00 = TREE_OPERAND (arg0, 0);
9692 tree tree01 = TREE_OPERAND (arg0, 1);
9693 if (TREE_CODE (tree01) == MULT_EXPR
9694 && TREE_CODE (tree00) == MULT_EXPR)
9697 tree0 = fold_build2 (PLUS_EXPR, type, tree01, arg1);
9698 return fold_build2 (PLUS_EXPR, type, tree00, tree0);
9704 /* (A << C1) + (A >> C2) if A is unsigned and C1+C2 is the size of A
9705 is a rotate of A by C1 bits. */
9706 /* (A << B) + (A >> (Z - B)) if A is unsigned and Z is the size of A
9707 is a rotate of A by B bits. */
9709 enum tree_code code0, code1;
9711 code0 = TREE_CODE (arg0);
9712 code1 = TREE_CODE (arg1);
9713 if (((code0 == RSHIFT_EXPR && code1 == LSHIFT_EXPR)
9714 || (code1 == RSHIFT_EXPR && code0 == LSHIFT_EXPR))
9715 && operand_equal_p (TREE_OPERAND (arg0, 0),
9716 TREE_OPERAND (arg1, 0), 0)
9717 && (rtype = TREE_TYPE (TREE_OPERAND (arg0, 0)),
9718 TYPE_UNSIGNED (rtype))
9719 /* Only create rotates in complete modes. Other cases are not
9720 expanded properly. */
9721 && TYPE_PRECISION (rtype) == GET_MODE_PRECISION (TYPE_MODE (rtype)))
9723 tree tree01, tree11;
9724 enum tree_code code01, code11;
9726 tree01 = TREE_OPERAND (arg0, 1);
9727 tree11 = TREE_OPERAND (arg1, 1);
9728 STRIP_NOPS (tree01);
9729 STRIP_NOPS (tree11);
9730 code01 = TREE_CODE (tree01);
9731 code11 = TREE_CODE (tree11);
9732 if (code01 == INTEGER_CST
9733 && code11 == INTEGER_CST
9734 && TREE_INT_CST_HIGH (tree01) == 0
9735 && TREE_INT_CST_HIGH (tree11) == 0
9736 && ((TREE_INT_CST_LOW (tree01) + TREE_INT_CST_LOW (tree11))
9737 == TYPE_PRECISION (TREE_TYPE (TREE_OPERAND (arg0, 0)))))
9738 return build2 (LROTATE_EXPR, type, TREE_OPERAND (arg0, 0),
9739 code0 == LSHIFT_EXPR ? tree01 : tree11);
9740 else if (code11 == MINUS_EXPR)
9742 tree tree110, tree111;
9743 tree110 = TREE_OPERAND (tree11, 0);
9744 tree111 = TREE_OPERAND (tree11, 1);
9745 STRIP_NOPS (tree110);
9746 STRIP_NOPS (tree111);
9747 if (TREE_CODE (tree110) == INTEGER_CST
9748 && 0 == compare_tree_int (tree110,
9750 (TREE_TYPE (TREE_OPERAND
9752 && operand_equal_p (tree01, tree111, 0))
9753 return build2 ((code0 == LSHIFT_EXPR
9756 type, TREE_OPERAND (arg0, 0), tree01);
9758 else if (code01 == MINUS_EXPR)
9760 tree tree010, tree011;
9761 tree010 = TREE_OPERAND (tree01, 0);
9762 tree011 = TREE_OPERAND (tree01, 1);
9763 STRIP_NOPS (tree010);
9764 STRIP_NOPS (tree011);
9765 if (TREE_CODE (tree010) == INTEGER_CST
9766 && 0 == compare_tree_int (tree010,
9768 (TREE_TYPE (TREE_OPERAND
9770 && operand_equal_p (tree11, tree011, 0))
9771 return build2 ((code0 != LSHIFT_EXPR
9774 type, TREE_OPERAND (arg0, 0), tree11);
9780 /* In most languages, can't associate operations on floats through
9781 parentheses. Rather than remember where the parentheses were, we
9782 don't associate floats at all, unless the user has specified
9784 And, we need to make sure type is not saturating. */
9786 if ((! FLOAT_TYPE_P (type) || flag_associative_math)
9787 && !TYPE_SATURATING (type))
9789 tree var0, con0, lit0, minus_lit0;
9790 tree var1, con1, lit1, minus_lit1;
9793 /* Split both trees into variables, constants, and literals. Then
9794 associate each group together, the constants with literals,
9795 then the result with variables. This increases the chances of
9796 literals being recombined later and of generating relocatable
9797 expressions for the sum of a constant and literal. */
9798 var0 = split_tree (arg0, code, &con0, &lit0, &minus_lit0, 0);
9799 var1 = split_tree (arg1, code, &con1, &lit1, &minus_lit1,
9800 code == MINUS_EXPR);
9802 /* With undefined overflow we can only associate constants
9803 with one variable. */
9804 if (((POINTER_TYPE_P (type) && POINTER_TYPE_OVERFLOW_UNDEFINED)
9805 || (INTEGRAL_TYPE_P (type) && !TYPE_OVERFLOW_WRAPS (type)))
9811 if (TREE_CODE (tmp0) == NEGATE_EXPR)
9812 tmp0 = TREE_OPERAND (tmp0, 0);
9813 if (TREE_CODE (tmp1) == NEGATE_EXPR)
9814 tmp1 = TREE_OPERAND (tmp1, 0);
9815 /* The only case we can still associate with two variables
9816 is if they are the same, modulo negation. */
9817 if (!operand_equal_p (tmp0, tmp1, 0))
9821 /* Only do something if we found more than two objects. Otherwise,
9822 nothing has changed and we risk infinite recursion. */
9824 && (2 < ((var0 != 0) + (var1 != 0)
9825 + (con0 != 0) + (con1 != 0)
9826 + (lit0 != 0) + (lit1 != 0)
9827 + (minus_lit0 != 0) + (minus_lit1 != 0))))
9829 /* Recombine MINUS_EXPR operands by using PLUS_EXPR. */
9830 if (code == MINUS_EXPR)
9833 var0 = associate_trees (var0, var1, code, type);
9834 con0 = associate_trees (con0, con1, code, type);
9835 lit0 = associate_trees (lit0, lit1, code, type);
9836 minus_lit0 = associate_trees (minus_lit0, minus_lit1, code, type);
9838 /* Preserve the MINUS_EXPR if the negative part of the literal is
9839 greater than the positive part. Otherwise, the multiplicative
9840 folding code (i.e extract_muldiv) may be fooled in case
9841 unsigned constants are subtracted, like in the following
9842 example: ((X*2 + 4) - 8U)/2. */
9843 if (minus_lit0 && lit0)
9845 if (TREE_CODE (lit0) == INTEGER_CST
9846 && TREE_CODE (minus_lit0) == INTEGER_CST
9847 && tree_int_cst_lt (lit0, minus_lit0))
9849 minus_lit0 = associate_trees (minus_lit0, lit0,
9855 lit0 = associate_trees (lit0, minus_lit0,
9863 return fold_convert (type,
9864 associate_trees (var0, minus_lit0,
9868 con0 = associate_trees (con0, minus_lit0,
9870 return fold_convert (type,
9871 associate_trees (var0, con0,
9876 con0 = associate_trees (con0, lit0, code, type);
9877 return fold_convert (type, associate_trees (var0, con0,
9885 /* Pointer simplifications for subtraction, simple reassociations. */
9886 if (POINTER_TYPE_P (TREE_TYPE (arg1)) && POINTER_TYPE_P (TREE_TYPE (arg0)))
9888 /* (PTR0 p+ A) - (PTR1 p+ B) -> (PTR0 - PTR1) + (A - B) */
9889 if (TREE_CODE (arg0) == POINTER_PLUS_EXPR
9890 && TREE_CODE (arg1) == POINTER_PLUS_EXPR)
9892 tree arg00 = fold_convert (type, TREE_OPERAND (arg0, 0));
9893 tree arg01 = fold_convert (type, TREE_OPERAND (arg0, 1));
9894 tree arg10 = fold_convert (type, TREE_OPERAND (arg1, 0));
9895 tree arg11 = fold_convert (type, TREE_OPERAND (arg1, 1));
9896 return fold_build2 (PLUS_EXPR, type,
9897 fold_build2 (MINUS_EXPR, type, arg00, arg10),
9898 fold_build2 (MINUS_EXPR, type, arg01, arg11));
9900 /* (PTR0 p+ A) - PTR1 -> (PTR0 - PTR1) + A, assuming PTR0 - PTR1 simplifies. */
9901 else if (TREE_CODE (arg0) == POINTER_PLUS_EXPR)
9903 tree arg00 = fold_convert (type, TREE_OPERAND (arg0, 0));
9904 tree arg01 = fold_convert (type, TREE_OPERAND (arg0, 1));
9905 tree tmp = fold_binary (MINUS_EXPR, type, arg00, fold_convert (type, arg1));
9907 return fold_build2 (PLUS_EXPR, type, tmp, arg01);
9910 /* A - (-B) -> A + B */
9911 if (TREE_CODE (arg1) == NEGATE_EXPR)
9912 return fold_build2 (PLUS_EXPR, type, op0,
9913 fold_convert (type, TREE_OPERAND (arg1, 0)));
9914 /* (-A) - B -> (-B) - A where B is easily negated and we can swap. */
9915 if (TREE_CODE (arg0) == NEGATE_EXPR
9916 && (FLOAT_TYPE_P (type)
9917 || INTEGRAL_TYPE_P (type))
9918 && negate_expr_p (arg1)
9919 && reorder_operands_p (arg0, arg1))
9920 return fold_build2 (MINUS_EXPR, type,
9921 fold_convert (type, negate_expr (arg1)),
9922 fold_convert (type, TREE_OPERAND (arg0, 0)));
9923 /* Convert -A - 1 to ~A. */
9924 if (INTEGRAL_TYPE_P (type)
9925 && TREE_CODE (arg0) == NEGATE_EXPR
9926 && integer_onep (arg1)
9927 && !TYPE_OVERFLOW_TRAPS (type))
9928 return fold_build1 (BIT_NOT_EXPR, type,
9929 fold_convert (type, TREE_OPERAND (arg0, 0)));
9931 /* Convert -1 - A to ~A. */
9932 if (INTEGRAL_TYPE_P (type)
9933 && integer_all_onesp (arg0))
9934 return fold_build1 (BIT_NOT_EXPR, type, op1);
9937 /* X - (X / CST) * CST is X % CST. */
9938 if (INTEGRAL_TYPE_P (type)
9939 && TREE_CODE (arg1) == MULT_EXPR
9940 && TREE_CODE (TREE_OPERAND (arg1, 0)) == TRUNC_DIV_EXPR
9941 && operand_equal_p (arg0,
9942 TREE_OPERAND (TREE_OPERAND (arg1, 0), 0), 0)
9943 && operand_equal_p (TREE_OPERAND (TREE_OPERAND (arg1, 0), 1),
9944 TREE_OPERAND (arg1, 1), 0))
9945 return fold_convert (type,
9946 fold_build2 (TRUNC_MOD_EXPR, TREE_TYPE (arg0),
9947 arg0, TREE_OPERAND (arg1, 1)));
9949 if (! FLOAT_TYPE_P (type))
9951 if (integer_zerop (arg0))
9952 return negate_expr (fold_convert (type, arg1));
9953 if (integer_zerop (arg1))
9954 return non_lvalue (fold_convert (type, arg0));
9956 /* Fold A - (A & B) into ~B & A. */
9957 if (!TREE_SIDE_EFFECTS (arg0)
9958 && TREE_CODE (arg1) == BIT_AND_EXPR)
9960 if (operand_equal_p (arg0, TREE_OPERAND (arg1, 1), 0))
9962 tree arg10 = fold_convert (type, TREE_OPERAND (arg1, 0));
9963 return fold_build2 (BIT_AND_EXPR, type,
9964 fold_build1 (BIT_NOT_EXPR, type, arg10),
9965 fold_convert (type, arg0));
9967 if (operand_equal_p (arg0, TREE_OPERAND (arg1, 0), 0))
9969 tree arg11 = fold_convert (type, TREE_OPERAND (arg1, 1));
9970 return fold_build2 (BIT_AND_EXPR, type,
9971 fold_build1 (BIT_NOT_EXPR, type, arg11),
9972 fold_convert (type, arg0));
9976 /* Fold (A & ~B) - (A & B) into (A ^ B) - B, where B is
9977 any power of 2 minus 1. */
9978 if (TREE_CODE (arg0) == BIT_AND_EXPR
9979 && TREE_CODE (arg1) == BIT_AND_EXPR
9980 && operand_equal_p (TREE_OPERAND (arg0, 0),
9981 TREE_OPERAND (arg1, 0), 0))
9983 tree mask0 = TREE_OPERAND (arg0, 1);
9984 tree mask1 = TREE_OPERAND (arg1, 1);
9985 tree tem = fold_build1 (BIT_NOT_EXPR, type, mask0);
9987 if (operand_equal_p (tem, mask1, 0))
9989 tem = fold_build2 (BIT_XOR_EXPR, type,
9990 TREE_OPERAND (arg0, 0), mask1);
9991 return fold_build2 (MINUS_EXPR, type, tem, mask1);
9996 /* See if ARG1 is zero and X - ARG1 reduces to X. */
9997 else if (fold_real_zero_addition_p (TREE_TYPE (arg0), arg1, 1))
9998 return non_lvalue (fold_convert (type, arg0));
10000 /* (ARG0 - ARG1) is the same as (-ARG1 + ARG0). So check whether
10001 ARG0 is zero and X + ARG0 reduces to X, since that would mean
10002 (-ARG1 + ARG0) reduces to -ARG1. */
10003 else if (fold_real_zero_addition_p (TREE_TYPE (arg1), arg0, 0))
10004 return negate_expr (fold_convert (type, arg1));
10006 /* Fold __complex__ ( x, 0 ) - __complex__ ( 0, y ) to
10007 __complex__ ( x, -y ). This is not the same for SNaNs or if
10008 signed zeros are involved. */
10009 if (!HONOR_SNANS (TYPE_MODE (TREE_TYPE (arg0)))
10010 && !HONOR_SIGNED_ZEROS (TYPE_MODE (TREE_TYPE (arg0)))
10011 && COMPLEX_FLOAT_TYPE_P (TREE_TYPE (arg0)))
10013 tree rtype = TREE_TYPE (TREE_TYPE (arg0));
10014 tree arg0r = fold_unary (REALPART_EXPR, rtype, arg0);
10015 tree arg0i = fold_unary (IMAGPART_EXPR, rtype, arg0);
10016 bool arg0rz = false, arg0iz = false;
10017 if ((arg0r && (arg0rz = real_zerop (arg0r)))
10018 || (arg0i && (arg0iz = real_zerop (arg0i))))
10020 tree arg1r = fold_unary (REALPART_EXPR, rtype, arg1);
10021 tree arg1i = fold_unary (IMAGPART_EXPR, rtype, arg1);
10022 if (arg0rz && arg1i && real_zerop (arg1i))
10024 tree rp = fold_build1 (NEGATE_EXPR, rtype,
10026 : build1 (REALPART_EXPR, rtype, arg1));
10027 tree ip = arg0i ? arg0i
10028 : build1 (IMAGPART_EXPR, rtype, arg0);
10029 return fold_build2 (COMPLEX_EXPR, type, rp, ip);
10031 else if (arg0iz && arg1r && real_zerop (arg1r))
10033 tree rp = arg0r ? arg0r
10034 : build1 (REALPART_EXPR, rtype, arg0);
10035 tree ip = fold_build1 (NEGATE_EXPR, rtype,
10037 : build1 (IMAGPART_EXPR, rtype, arg1));
10038 return fold_build2 (COMPLEX_EXPR, type, rp, ip);
10043 /* Fold &x - &x. This can happen from &x.foo - &x.
10044 This is unsafe for certain floats even in non-IEEE formats.
10045 In IEEE, it is unsafe because it does wrong for NaNs.
10046 Also note that operand_equal_p is always false if an operand
10049 if ((!FLOAT_TYPE_P (type) || !HONOR_NANS (TYPE_MODE (type)))
10050 && operand_equal_p (arg0, arg1, 0))
10051 return fold_convert (type, integer_zero_node);
10053 /* A - B -> A + (-B) if B is easily negatable. */
10054 if (negate_expr_p (arg1)
10055 && ((FLOAT_TYPE_P (type)
10056 /* Avoid this transformation if B is a positive REAL_CST. */
10057 && (TREE_CODE (arg1) != REAL_CST
10058 || REAL_VALUE_NEGATIVE (TREE_REAL_CST (arg1))))
10059 || INTEGRAL_TYPE_P (type)))
10060 return fold_build2 (PLUS_EXPR, type,
10061 fold_convert (type, arg0),
10062 fold_convert (type, negate_expr (arg1)));
10064 /* Try folding difference of addresses. */
10066 HOST_WIDE_INT diff;
10068 if ((TREE_CODE (arg0) == ADDR_EXPR
10069 || TREE_CODE (arg1) == ADDR_EXPR)
10070 && ptr_difference_const (arg0, arg1, &diff))
10071 return build_int_cst_type (type, diff);
10074 /* Fold &a[i] - &a[j] to i-j. */
10075 if (TREE_CODE (arg0) == ADDR_EXPR
10076 && TREE_CODE (TREE_OPERAND (arg0, 0)) == ARRAY_REF
10077 && TREE_CODE (arg1) == ADDR_EXPR
10078 && TREE_CODE (TREE_OPERAND (arg1, 0)) == ARRAY_REF)
10080 tree aref0 = TREE_OPERAND (arg0, 0);
10081 tree aref1 = TREE_OPERAND (arg1, 0);
10082 if (operand_equal_p (TREE_OPERAND (aref0, 0),
10083 TREE_OPERAND (aref1, 0), 0))
10085 tree op0 = fold_convert (type, TREE_OPERAND (aref0, 1));
10086 tree op1 = fold_convert (type, TREE_OPERAND (aref1, 1));
10087 tree esz = array_ref_element_size (aref0);
10088 tree diff = build2 (MINUS_EXPR, type, op0, op1);
10089 return fold_build2 (MULT_EXPR, type, diff,
10090 fold_convert (type, esz));
10095 if (flag_unsafe_math_optimizations
10096 && (TREE_CODE (arg0) == RDIV_EXPR || TREE_CODE (arg0) == MULT_EXPR)
10097 && (TREE_CODE (arg1) == RDIV_EXPR || TREE_CODE (arg1) == MULT_EXPR)
10098 && (tem = distribute_real_division (code, type, arg0, arg1)))
10101 /* Handle (A1 * C1) - (A2 * C2) with A1, A2 or C1, C2 being the
10102 same or one. Make sure type is not saturating.
10103 fold_plusminus_mult_expr will re-associate. */
10104 if ((TREE_CODE (arg0) == MULT_EXPR
10105 || TREE_CODE (arg1) == MULT_EXPR)
10106 && !TYPE_SATURATING (type)
10107 && (!FLOAT_TYPE_P (type) || flag_associative_math))
10109 tree tem = fold_plusminus_mult_expr (code, type, arg0, arg1);
10117 /* (-A) * (-B) -> A * B */
10118 if (TREE_CODE (arg0) == NEGATE_EXPR && negate_expr_p (arg1))
10119 return fold_build2 (MULT_EXPR, type,
10120 fold_convert (type, TREE_OPERAND (arg0, 0)),
10121 fold_convert (type, negate_expr (arg1)));
10122 if (TREE_CODE (arg1) == NEGATE_EXPR && negate_expr_p (arg0))
10123 return fold_build2 (MULT_EXPR, type,
10124 fold_convert (type, negate_expr (arg0)),
10125 fold_convert (type, TREE_OPERAND (arg1, 0)));
10127 if (! FLOAT_TYPE_P (type))
10129 if (integer_zerop (arg1))
10130 return omit_one_operand (type, arg1, arg0);
10131 if (integer_onep (arg1))
10132 return non_lvalue (fold_convert (type, arg0));
10133 /* Transform x * -1 into -x. Make sure to do the negation
10134 on the original operand with conversions not stripped
10135 because we can only strip non-sign-changing conversions. */
10136 if (integer_all_onesp (arg1))
10137 return fold_convert (type, negate_expr (op0));
10138 /* Transform x * -C into -x * C if x is easily negatable. */
10139 if (TREE_CODE (arg1) == INTEGER_CST
10140 && tree_int_cst_sgn (arg1) == -1
10141 && negate_expr_p (arg0)
10142 && (tem = negate_expr (arg1)) != arg1
10143 && !TREE_OVERFLOW (tem))
10144 return fold_build2 (MULT_EXPR, type,
10145 fold_convert (type, negate_expr (arg0)), tem);
10147 /* (a * (1 << b)) is (a << b) */
10148 if (TREE_CODE (arg1) == LSHIFT_EXPR
10149 && integer_onep (TREE_OPERAND (arg1, 0)))
10150 return fold_build2 (LSHIFT_EXPR, type, op0,
10151 TREE_OPERAND (arg1, 1));
10152 if (TREE_CODE (arg0) == LSHIFT_EXPR
10153 && integer_onep (TREE_OPERAND (arg0, 0)))
10154 return fold_build2 (LSHIFT_EXPR, type, op1,
10155 TREE_OPERAND (arg0, 1));
10157 /* (A + A) * C -> A * 2 * C */
10158 if (TREE_CODE (arg0) == PLUS_EXPR
10159 && TREE_CODE (arg1) == INTEGER_CST
10160 && operand_equal_p (TREE_OPERAND (arg0, 0),
10161 TREE_OPERAND (arg0, 1), 0))
10162 return fold_build2 (MULT_EXPR, type,
10163 omit_one_operand (type, TREE_OPERAND (arg0, 0),
10164 TREE_OPERAND (arg0, 1)),
10165 fold_build2 (MULT_EXPR, type,
10166 build_int_cst (type, 2) , arg1));
10168 strict_overflow_p = false;
10169 if (TREE_CODE (arg1) == INTEGER_CST
10170 && 0 != (tem = extract_muldiv (op0, arg1, code, NULL_TREE,
10171 &strict_overflow_p)))
10173 if (strict_overflow_p)
10174 fold_overflow_warning (("assuming signed overflow does not "
10175 "occur when simplifying "
10177 WARN_STRICT_OVERFLOW_MISC);
10178 return fold_convert (type, tem);
10181 /* Optimize z * conj(z) for integer complex numbers. */
10182 if (TREE_CODE (arg0) == CONJ_EXPR
10183 && operand_equal_p (TREE_OPERAND (arg0, 0), arg1, 0))
10184 return fold_mult_zconjz (type, arg1);
10185 if (TREE_CODE (arg1) == CONJ_EXPR
10186 && operand_equal_p (arg0, TREE_OPERAND (arg1, 0), 0))
10187 return fold_mult_zconjz (type, arg0);
10191 /* Maybe fold x * 0 to 0. The expressions aren't the same
10192 when x is NaN, since x * 0 is also NaN. Nor are they the
10193 same in modes with signed zeros, since multiplying a
10194 negative value by 0 gives -0, not +0. */
10195 if (!HONOR_NANS (TYPE_MODE (TREE_TYPE (arg0)))
10196 && !HONOR_SIGNED_ZEROS (TYPE_MODE (TREE_TYPE (arg0)))
10197 && real_zerop (arg1))
10198 return omit_one_operand (type, arg1, arg0);
10199 /* In IEEE floating point, x*1 is not equivalent to x for snans. */
10200 if (!HONOR_SNANS (TYPE_MODE (TREE_TYPE (arg0)))
10201 && real_onep (arg1))
10202 return non_lvalue (fold_convert (type, arg0));
10204 /* Transform x * -1.0 into -x. */
10205 if (!HONOR_SNANS (TYPE_MODE (TREE_TYPE (arg0)))
10206 && real_minus_onep (arg1))
10207 return fold_convert (type, negate_expr (arg0));
10209 /* Convert (C1/X)*C2 into (C1*C2)/X. This transformation may change
10210 the result for floating point types due to rounding so it is applied
10211 only if -fassociative-math was specify. */
10212 if (flag_associative_math
10213 && TREE_CODE (arg0) == RDIV_EXPR
10214 && TREE_CODE (arg1) == REAL_CST
10215 && TREE_CODE (TREE_OPERAND (arg0, 0)) == REAL_CST)
10217 tree tem = const_binop (MULT_EXPR, TREE_OPERAND (arg0, 0),
10220 return fold_build2 (RDIV_EXPR, type, tem,
10221 TREE_OPERAND (arg0, 1));
10224 /* Strip sign operations from X in X*X, i.e. -Y*-Y -> Y*Y. */
10225 if (operand_equal_p (arg0, arg1, 0))
10227 tree tem = fold_strip_sign_ops (arg0);
10228 if (tem != NULL_TREE)
10230 tem = fold_convert (type, tem);
10231 return fold_build2 (MULT_EXPR, type, tem, tem);
10235 /* Fold z * +-I to __complex__ (-+__imag z, +-__real z).
10236 This is not the same for NaNs or if signed zeros are
10238 if (!HONOR_NANS (TYPE_MODE (TREE_TYPE (arg0)))
10239 && !HONOR_SIGNED_ZEROS (TYPE_MODE (TREE_TYPE (arg0)))
10240 && COMPLEX_FLOAT_TYPE_P (TREE_TYPE (arg0))
10241 && TREE_CODE (arg1) == COMPLEX_CST
10242 && real_zerop (TREE_REALPART (arg1)))
10244 tree rtype = TREE_TYPE (TREE_TYPE (arg0));
10245 if (real_onep (TREE_IMAGPART (arg1)))
10246 return fold_build2 (COMPLEX_EXPR, type,
10247 negate_expr (fold_build1 (IMAGPART_EXPR,
10249 fold_build1 (REALPART_EXPR, rtype, arg0));
10250 else if (real_minus_onep (TREE_IMAGPART (arg1)))
10251 return fold_build2 (COMPLEX_EXPR, type,
10252 fold_build1 (IMAGPART_EXPR, rtype, arg0),
10253 negate_expr (fold_build1 (REALPART_EXPR,
10257 /* Optimize z * conj(z) for floating point complex numbers.
10258 Guarded by flag_unsafe_math_optimizations as non-finite
10259 imaginary components don't produce scalar results. */
10260 if (flag_unsafe_math_optimizations
10261 && TREE_CODE (arg0) == CONJ_EXPR
10262 && operand_equal_p (TREE_OPERAND (arg0, 0), arg1, 0))
10263 return fold_mult_zconjz (type, arg1);
10264 if (flag_unsafe_math_optimizations
10265 && TREE_CODE (arg1) == CONJ_EXPR
10266 && operand_equal_p (arg0, TREE_OPERAND (arg1, 0), 0))
10267 return fold_mult_zconjz (type, arg0);
10269 if (flag_unsafe_math_optimizations)
10271 enum built_in_function fcode0 = builtin_mathfn_code (arg0);
10272 enum built_in_function fcode1 = builtin_mathfn_code (arg1);
10274 /* Optimizations of root(...)*root(...). */
10275 if (fcode0 == fcode1 && BUILTIN_ROOT_P (fcode0))
10278 tree arg00 = CALL_EXPR_ARG (arg0, 0);
10279 tree arg10 = CALL_EXPR_ARG (arg1, 0);
10281 /* Optimize sqrt(x)*sqrt(x) as x. */
10282 if (BUILTIN_SQRT_P (fcode0)
10283 && operand_equal_p (arg00, arg10, 0)
10284 && ! HONOR_SNANS (TYPE_MODE (type)))
10287 /* Optimize root(x)*root(y) as root(x*y). */
10288 rootfn = TREE_OPERAND (CALL_EXPR_FN (arg0), 0);
10289 arg = fold_build2 (MULT_EXPR, type, arg00, arg10);
10290 return build_call_expr (rootfn, 1, arg);
10293 /* Optimize expN(x)*expN(y) as expN(x+y). */
10294 if (fcode0 == fcode1 && BUILTIN_EXPONENT_P (fcode0))
10296 tree expfn = TREE_OPERAND (CALL_EXPR_FN (arg0), 0);
10297 tree arg = fold_build2 (PLUS_EXPR, type,
10298 CALL_EXPR_ARG (arg0, 0),
10299 CALL_EXPR_ARG (arg1, 0));
10300 return build_call_expr (expfn, 1, arg);
10303 /* Optimizations of pow(...)*pow(...). */
10304 if ((fcode0 == BUILT_IN_POW && fcode1 == BUILT_IN_POW)
10305 || (fcode0 == BUILT_IN_POWF && fcode1 == BUILT_IN_POWF)
10306 || (fcode0 == BUILT_IN_POWL && fcode1 == BUILT_IN_POWL))
10308 tree arg00 = CALL_EXPR_ARG (arg0, 0);
10309 tree arg01 = CALL_EXPR_ARG (arg0, 1);
10310 tree arg10 = CALL_EXPR_ARG (arg1, 0);
10311 tree arg11 = CALL_EXPR_ARG (arg1, 1);
10313 /* Optimize pow(x,y)*pow(z,y) as pow(x*z,y). */
10314 if (operand_equal_p (arg01, arg11, 0))
10316 tree powfn = TREE_OPERAND (CALL_EXPR_FN (arg0), 0);
10317 tree arg = fold_build2 (MULT_EXPR, type, arg00, arg10);
10318 return build_call_expr (powfn, 2, arg, arg01);
10321 /* Optimize pow(x,y)*pow(x,z) as pow(x,y+z). */
10322 if (operand_equal_p (arg00, arg10, 0))
10324 tree powfn = TREE_OPERAND (CALL_EXPR_FN (arg0), 0);
10325 tree arg = fold_build2 (PLUS_EXPR, type, arg01, arg11);
10326 return build_call_expr (powfn, 2, arg00, arg);
10330 /* Optimize tan(x)*cos(x) as sin(x). */
10331 if (((fcode0 == BUILT_IN_TAN && fcode1 == BUILT_IN_COS)
10332 || (fcode0 == BUILT_IN_TANF && fcode1 == BUILT_IN_COSF)
10333 || (fcode0 == BUILT_IN_TANL && fcode1 == BUILT_IN_COSL)
10334 || (fcode0 == BUILT_IN_COS && fcode1 == BUILT_IN_TAN)
10335 || (fcode0 == BUILT_IN_COSF && fcode1 == BUILT_IN_TANF)
10336 || (fcode0 == BUILT_IN_COSL && fcode1 == BUILT_IN_TANL))
10337 && operand_equal_p (CALL_EXPR_ARG (arg0, 0),
10338 CALL_EXPR_ARG (arg1, 0), 0))
10340 tree sinfn = mathfn_built_in (type, BUILT_IN_SIN);
10342 if (sinfn != NULL_TREE)
10343 return build_call_expr (sinfn, 1, CALL_EXPR_ARG (arg0, 0));
10346 /* Optimize x*pow(x,c) as pow(x,c+1). */
10347 if (fcode1 == BUILT_IN_POW
10348 || fcode1 == BUILT_IN_POWF
10349 || fcode1 == BUILT_IN_POWL)
10351 tree arg10 = CALL_EXPR_ARG (arg1, 0);
10352 tree arg11 = CALL_EXPR_ARG (arg1, 1);
10353 if (TREE_CODE (arg11) == REAL_CST
10354 && !TREE_OVERFLOW (arg11)
10355 && operand_equal_p (arg0, arg10, 0))
10357 tree powfn = TREE_OPERAND (CALL_EXPR_FN (arg1), 0);
10361 c = TREE_REAL_CST (arg11);
10362 real_arithmetic (&c, PLUS_EXPR, &c, &dconst1);
10363 arg = build_real (type, c);
10364 return build_call_expr (powfn, 2, arg0, arg);
10368 /* Optimize pow(x,c)*x as pow(x,c+1). */
10369 if (fcode0 == BUILT_IN_POW
10370 || fcode0 == BUILT_IN_POWF
10371 || fcode0 == BUILT_IN_POWL)
10373 tree arg00 = CALL_EXPR_ARG (arg0, 0);
10374 tree arg01 = CALL_EXPR_ARG (arg0, 1);
10375 if (TREE_CODE (arg01) == REAL_CST
10376 && !TREE_OVERFLOW (arg01)
10377 && operand_equal_p (arg1, arg00, 0))
10379 tree powfn = TREE_OPERAND (CALL_EXPR_FN (arg0), 0);
10383 c = TREE_REAL_CST (arg01);
10384 real_arithmetic (&c, PLUS_EXPR, &c, &dconst1);
10385 arg = build_real (type, c);
10386 return build_call_expr (powfn, 2, arg1, arg);
10390 /* Optimize x*x as pow(x,2.0), which is expanded as x*x. */
10391 if (! optimize_size
10392 && operand_equal_p (arg0, arg1, 0))
10394 tree powfn = mathfn_built_in (type, BUILT_IN_POW);
10398 tree arg = build_real (type, dconst2);
10399 return build_call_expr (powfn, 2, arg0, arg);
10408 if (integer_all_onesp (arg1))
10409 return omit_one_operand (type, arg1, arg0);
10410 if (integer_zerop (arg1))
10411 return non_lvalue (fold_convert (type, arg0));
10412 if (operand_equal_p (arg0, arg1, 0))
10413 return non_lvalue (fold_convert (type, arg0));
10415 /* ~X | X is -1. */
10416 if (TREE_CODE (arg0) == BIT_NOT_EXPR
10417 && operand_equal_p (TREE_OPERAND (arg0, 0), arg1, 0))
10419 t1 = fold_convert (type, integer_zero_node);
10420 t1 = fold_unary (BIT_NOT_EXPR, type, t1);
10421 return omit_one_operand (type, t1, arg1);
10424 /* X | ~X is -1. */
10425 if (TREE_CODE (arg1) == BIT_NOT_EXPR
10426 && operand_equal_p (arg0, TREE_OPERAND (arg1, 0), 0))
10428 t1 = fold_convert (type, integer_zero_node);
10429 t1 = fold_unary (BIT_NOT_EXPR, type, t1);
10430 return omit_one_operand (type, t1, arg0);
10433 /* Canonicalize (X & C1) | C2. */
10434 if (TREE_CODE (arg0) == BIT_AND_EXPR
10435 && TREE_CODE (arg1) == INTEGER_CST
10436 && TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST)
10438 unsigned HOST_WIDE_INT hi1, lo1, hi2, lo2, hi3, lo3, mlo, mhi;
10439 int width = TYPE_PRECISION (type), w;
10440 hi1 = TREE_INT_CST_HIGH (TREE_OPERAND (arg0, 1));
10441 lo1 = TREE_INT_CST_LOW (TREE_OPERAND (arg0, 1));
10442 hi2 = TREE_INT_CST_HIGH (arg1);
10443 lo2 = TREE_INT_CST_LOW (arg1);
10445 /* If (C1&C2) == C1, then (X&C1)|C2 becomes (X,C2). */
10446 if ((hi1 & hi2) == hi1 && (lo1 & lo2) == lo1)
10447 return omit_one_operand (type, arg1, TREE_OPERAND (arg0, 0));
10449 if (width > HOST_BITS_PER_WIDE_INT)
10451 mhi = (unsigned HOST_WIDE_INT) -1
10452 >> (2 * HOST_BITS_PER_WIDE_INT - width);
10458 mlo = (unsigned HOST_WIDE_INT) -1
10459 >> (HOST_BITS_PER_WIDE_INT - width);
10462 /* If (C1|C2) == ~0 then (X&C1)|C2 becomes X|C2. */
10463 if ((~(hi1 | hi2) & mhi) == 0 && (~(lo1 | lo2) & mlo) == 0)
10464 return fold_build2 (BIT_IOR_EXPR, type,
10465 TREE_OPERAND (arg0, 0), arg1);
10467 /* Minimize the number of bits set in C1, i.e. C1 := C1 & ~C2,
10468 unless (C1 & ~C2) | (C2 & C3) for some C3 is a mask of some
10469 mode which allows further optimizations. */
10476 for (w = BITS_PER_UNIT;
10477 w <= width && w <= HOST_BITS_PER_WIDE_INT;
10480 unsigned HOST_WIDE_INT mask
10481 = (unsigned HOST_WIDE_INT) -1 >> (HOST_BITS_PER_WIDE_INT - w);
10482 if (((lo1 | lo2) & mask) == mask
10483 && (lo1 & ~mask) == 0 && hi1 == 0)
10490 if (hi3 != hi1 || lo3 != lo1)
10491 return fold_build2 (BIT_IOR_EXPR, type,
10492 fold_build2 (BIT_AND_EXPR, type,
10493 TREE_OPERAND (arg0, 0),
10494 build_int_cst_wide (type,
10499 /* (X & Y) | Y is (X, Y). */
10500 if (TREE_CODE (arg0) == BIT_AND_EXPR
10501 && operand_equal_p (TREE_OPERAND (arg0, 1), arg1, 0))
10502 return omit_one_operand (type, arg1, TREE_OPERAND (arg0, 0));
10503 /* (X & Y) | X is (Y, X). */
10504 if (TREE_CODE (arg0) == BIT_AND_EXPR
10505 && operand_equal_p (TREE_OPERAND (arg0, 0), arg1, 0)
10506 && reorder_operands_p (TREE_OPERAND (arg0, 1), arg1))
10507 return omit_one_operand (type, arg1, TREE_OPERAND (arg0, 1));
10508 /* X | (X & Y) is (Y, X). */
10509 if (TREE_CODE (arg1) == BIT_AND_EXPR
10510 && operand_equal_p (arg0, TREE_OPERAND (arg1, 0), 0)
10511 && reorder_operands_p (arg0, TREE_OPERAND (arg1, 1)))
10512 return omit_one_operand (type, arg0, TREE_OPERAND (arg1, 1));
10513 /* X | (Y & X) is (Y, X). */
10514 if (TREE_CODE (arg1) == BIT_AND_EXPR
10515 && operand_equal_p (arg0, TREE_OPERAND (arg1, 1), 0)
10516 && reorder_operands_p (arg0, TREE_OPERAND (arg1, 0)))
10517 return omit_one_operand (type, arg0, TREE_OPERAND (arg1, 0));
10519 t1 = distribute_bit_expr (code, type, arg0, arg1);
10520 if (t1 != NULL_TREE)
10523 /* Convert (or (not arg0) (not arg1)) to (not (and (arg0) (arg1))).
10525 This results in more efficient code for machines without a NAND
10526 instruction. Combine will canonicalize to the first form
10527 which will allow use of NAND instructions provided by the
10528 backend if they exist. */
10529 if (TREE_CODE (arg0) == BIT_NOT_EXPR
10530 && TREE_CODE (arg1) == BIT_NOT_EXPR)
10532 return fold_build1 (BIT_NOT_EXPR, type,
10533 build2 (BIT_AND_EXPR, type,
10534 fold_convert (type,
10535 TREE_OPERAND (arg0, 0)),
10536 fold_convert (type,
10537 TREE_OPERAND (arg1, 0))));
10540 /* See if this can be simplified into a rotate first. If that
10541 is unsuccessful continue in the association code. */
10545 if (integer_zerop (arg1))
10546 return non_lvalue (fold_convert (type, arg0));
10547 if (integer_all_onesp (arg1))
10548 return fold_build1 (BIT_NOT_EXPR, type, op0);
10549 if (operand_equal_p (arg0, arg1, 0))
10550 return omit_one_operand (type, integer_zero_node, arg0);
10552 /* ~X ^ X is -1. */
10553 if (TREE_CODE (arg0) == BIT_NOT_EXPR
10554 && operand_equal_p (TREE_OPERAND (arg0, 0), arg1, 0))
10556 t1 = fold_convert (type, integer_zero_node);
10557 t1 = fold_unary (BIT_NOT_EXPR, type, t1);
10558 return omit_one_operand (type, t1, arg1);
10561 /* X ^ ~X is -1. */
10562 if (TREE_CODE (arg1) == BIT_NOT_EXPR
10563 && operand_equal_p (arg0, TREE_OPERAND (arg1, 0), 0))
10565 t1 = fold_convert (type, integer_zero_node);
10566 t1 = fold_unary (BIT_NOT_EXPR, type, t1);
10567 return omit_one_operand (type, t1, arg0);
10570 /* If we are XORing two BIT_AND_EXPR's, both of which are and'ing
10571 with a constant, and the two constants have no bits in common,
10572 we should treat this as a BIT_IOR_EXPR since this may produce more
10573 simplifications. */
10574 if (TREE_CODE (arg0) == BIT_AND_EXPR
10575 && TREE_CODE (arg1) == BIT_AND_EXPR
10576 && TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST
10577 && TREE_CODE (TREE_OPERAND (arg1, 1)) == INTEGER_CST
10578 && integer_zerop (const_binop (BIT_AND_EXPR,
10579 TREE_OPERAND (arg0, 1),
10580 TREE_OPERAND (arg1, 1), 0)))
10582 code = BIT_IOR_EXPR;
10586 /* (X | Y) ^ X -> Y & ~ X*/
10587 if (TREE_CODE (arg0) == BIT_IOR_EXPR
10588 && operand_equal_p (TREE_OPERAND (arg0, 0), arg1, 0))
10590 tree t2 = TREE_OPERAND (arg0, 1);
10591 t1 = fold_build1 (BIT_NOT_EXPR, TREE_TYPE (arg1),
10593 t1 = fold_build2 (BIT_AND_EXPR, type, fold_convert (type, t2),
10594 fold_convert (type, t1));
10598 /* (Y | X) ^ X -> Y & ~ X*/
10599 if (TREE_CODE (arg0) == BIT_IOR_EXPR
10600 && operand_equal_p (TREE_OPERAND (arg0, 1), arg1, 0))
10602 tree t2 = TREE_OPERAND (arg0, 0);
10603 t1 = fold_build1 (BIT_NOT_EXPR, TREE_TYPE (arg1),
10605 t1 = fold_build2 (BIT_AND_EXPR, type, fold_convert (type, t2),
10606 fold_convert (type, t1));
10610 /* X ^ (X | Y) -> Y & ~ X*/
10611 if (TREE_CODE (arg1) == BIT_IOR_EXPR
10612 && operand_equal_p (TREE_OPERAND (arg1, 0), arg0, 0))
10614 tree t2 = TREE_OPERAND (arg1, 1);
10615 t1 = fold_build1 (BIT_NOT_EXPR, TREE_TYPE (arg0),
10617 t1 = fold_build2 (BIT_AND_EXPR, type, fold_convert (type, t2),
10618 fold_convert (type, t1));
10622 /* X ^ (Y | X) -> Y & ~ X*/
10623 if (TREE_CODE (arg1) == BIT_IOR_EXPR
10624 && operand_equal_p (TREE_OPERAND (arg1, 1), arg0, 0))
10626 tree t2 = TREE_OPERAND (arg1, 0);
10627 t1 = fold_build1 (BIT_NOT_EXPR, TREE_TYPE (arg0),
10629 t1 = fold_build2 (BIT_AND_EXPR, type, fold_convert (type, t2),
10630 fold_convert (type, t1));
10634 /* Convert ~X ^ ~Y to X ^ Y. */
10635 if (TREE_CODE (arg0) == BIT_NOT_EXPR
10636 && TREE_CODE (arg1) == BIT_NOT_EXPR)
10637 return fold_build2 (code, type,
10638 fold_convert (type, TREE_OPERAND (arg0, 0)),
10639 fold_convert (type, TREE_OPERAND (arg1, 0)));
10641 /* Convert ~X ^ C to X ^ ~C. */
10642 if (TREE_CODE (arg0) == BIT_NOT_EXPR
10643 && TREE_CODE (arg1) == INTEGER_CST)
10644 return fold_build2 (code, type,
10645 fold_convert (type, TREE_OPERAND (arg0, 0)),
10646 fold_build1 (BIT_NOT_EXPR, type, arg1));
10648 /* Fold (X & 1) ^ 1 as (X & 1) == 0. */
10649 if (TREE_CODE (arg0) == BIT_AND_EXPR
10650 && integer_onep (TREE_OPERAND (arg0, 1))
10651 && integer_onep (arg1))
10652 return fold_build2 (EQ_EXPR, type, arg0,
10653 build_int_cst (TREE_TYPE (arg0), 0));
10655 /* Fold (X & Y) ^ Y as ~X & Y. */
10656 if (TREE_CODE (arg0) == BIT_AND_EXPR
10657 && operand_equal_p (TREE_OPERAND (arg0, 1), arg1, 0))
10659 tem = fold_convert (type, TREE_OPERAND (arg0, 0));
10660 return fold_build2 (BIT_AND_EXPR, type,
10661 fold_build1 (BIT_NOT_EXPR, type, tem),
10662 fold_convert (type, arg1));
10664 /* Fold (X & Y) ^ X as ~Y & X. */
10665 if (TREE_CODE (arg0) == BIT_AND_EXPR
10666 && operand_equal_p (TREE_OPERAND (arg0, 0), arg1, 0)
10667 && reorder_operands_p (TREE_OPERAND (arg0, 1), arg1))
10669 tem = fold_convert (type, TREE_OPERAND (arg0, 1));
10670 return fold_build2 (BIT_AND_EXPR, type,
10671 fold_build1 (BIT_NOT_EXPR, type, tem),
10672 fold_convert (type, arg1));
10674 /* Fold X ^ (X & Y) as X & ~Y. */
10675 if (TREE_CODE (arg1) == BIT_AND_EXPR
10676 && operand_equal_p (arg0, TREE_OPERAND (arg1, 0), 0))
10678 tem = fold_convert (type, TREE_OPERAND (arg1, 1));
10679 return fold_build2 (BIT_AND_EXPR, type,
10680 fold_convert (type, arg0),
10681 fold_build1 (BIT_NOT_EXPR, type, tem));
10683 /* Fold X ^ (Y & X) as ~Y & X. */
10684 if (TREE_CODE (arg1) == BIT_AND_EXPR
10685 && operand_equal_p (arg0, TREE_OPERAND (arg1, 1), 0)
10686 && reorder_operands_p (arg0, TREE_OPERAND (arg1, 0)))
10688 tem = fold_convert (type, TREE_OPERAND (arg1, 0));
10689 return fold_build2 (BIT_AND_EXPR, type,
10690 fold_build1 (BIT_NOT_EXPR, type, tem),
10691 fold_convert (type, arg0));
10694 /* See if this can be simplified into a rotate first. If that
10695 is unsuccessful continue in the association code. */
10699 if (integer_all_onesp (arg1))
10700 return non_lvalue (fold_convert (type, arg0));
10701 if (integer_zerop (arg1))
10702 return omit_one_operand (type, arg1, arg0);
10703 if (operand_equal_p (arg0, arg1, 0))
10704 return non_lvalue (fold_convert (type, arg0));
10706 /* ~X & X is always zero. */
10707 if (TREE_CODE (arg0) == BIT_NOT_EXPR
10708 && operand_equal_p (TREE_OPERAND (arg0, 0), arg1, 0))
10709 return omit_one_operand (type, integer_zero_node, arg1);
10711 /* X & ~X is always zero. */
10712 if (TREE_CODE (arg1) == BIT_NOT_EXPR
10713 && operand_equal_p (arg0, TREE_OPERAND (arg1, 0), 0))
10714 return omit_one_operand (type, integer_zero_node, arg0);
10716 /* Canonicalize (X | C1) & C2 as (X & C2) | (C1 & C2). */
10717 if (TREE_CODE (arg0) == BIT_IOR_EXPR
10718 && TREE_CODE (arg1) == INTEGER_CST
10719 && TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST)
10721 tree tmp1 = fold_convert (TREE_TYPE (arg0), arg1);
10722 tree tmp2 = fold_build2 (BIT_AND_EXPR, TREE_TYPE (arg0),
10723 TREE_OPERAND (arg0, 0), tmp1);
10724 tree tmp3 = fold_build2 (BIT_AND_EXPR, TREE_TYPE (arg0),
10725 TREE_OPERAND (arg0, 1), tmp1);
10726 return fold_convert (type,
10727 fold_build2 (BIT_IOR_EXPR, TREE_TYPE (arg0),
10731 /* (X | Y) & Y is (X, Y). */
10732 if (TREE_CODE (arg0) == BIT_IOR_EXPR
10733 && operand_equal_p (TREE_OPERAND (arg0, 1), arg1, 0))
10734 return omit_one_operand (type, arg1, TREE_OPERAND (arg0, 0));
10735 /* (X | Y) & X is (Y, X). */
10736 if (TREE_CODE (arg0) == BIT_IOR_EXPR
10737 && operand_equal_p (TREE_OPERAND (arg0, 0), arg1, 0)
10738 && reorder_operands_p (TREE_OPERAND (arg0, 1), arg1))
10739 return omit_one_operand (type, arg1, TREE_OPERAND (arg0, 1));
10740 /* X & (X | Y) is (Y, X). */
10741 if (TREE_CODE (arg1) == BIT_IOR_EXPR
10742 && operand_equal_p (arg0, TREE_OPERAND (arg1, 0), 0)
10743 && reorder_operands_p (arg0, TREE_OPERAND (arg1, 1)))
10744 return omit_one_operand (type, arg0, TREE_OPERAND (arg1, 1));
10745 /* X & (Y | X) is (Y, X). */
10746 if (TREE_CODE (arg1) == BIT_IOR_EXPR
10747 && operand_equal_p (arg0, TREE_OPERAND (arg1, 1), 0)
10748 && reorder_operands_p (arg0, TREE_OPERAND (arg1, 0)))
10749 return omit_one_operand (type, arg0, TREE_OPERAND (arg1, 0));
10751 /* Fold (X ^ 1) & 1 as (X & 1) == 0. */
10752 if (TREE_CODE (arg0) == BIT_XOR_EXPR
10753 && integer_onep (TREE_OPERAND (arg0, 1))
10754 && integer_onep (arg1))
10756 tem = TREE_OPERAND (arg0, 0);
10757 return fold_build2 (EQ_EXPR, type,
10758 fold_build2 (BIT_AND_EXPR, TREE_TYPE (tem), tem,
10759 build_int_cst (TREE_TYPE (tem), 1)),
10760 build_int_cst (TREE_TYPE (tem), 0));
10762 /* Fold ~X & 1 as (X & 1) == 0. */
10763 if (TREE_CODE (arg0) == BIT_NOT_EXPR
10764 && integer_onep (arg1))
10766 tem = TREE_OPERAND (arg0, 0);
10767 return fold_build2 (EQ_EXPR, type,
10768 fold_build2 (BIT_AND_EXPR, TREE_TYPE (tem), tem,
10769 build_int_cst (TREE_TYPE (tem), 1)),
10770 build_int_cst (TREE_TYPE (tem), 0));
10773 /* Fold (X ^ Y) & Y as ~X & Y. */
10774 if (TREE_CODE (arg0) == BIT_XOR_EXPR
10775 && operand_equal_p (TREE_OPERAND (arg0, 1), arg1, 0))
10777 tem = fold_convert (type, TREE_OPERAND (arg0, 0));
10778 return fold_build2 (BIT_AND_EXPR, type,
10779 fold_build1 (BIT_NOT_EXPR, type, tem),
10780 fold_convert (type, arg1));
10782 /* Fold (X ^ Y) & X as ~Y & X. */
10783 if (TREE_CODE (arg0) == BIT_XOR_EXPR
10784 && operand_equal_p (TREE_OPERAND (arg0, 0), arg1, 0)
10785 && reorder_operands_p (TREE_OPERAND (arg0, 1), arg1))
10787 tem = fold_convert (type, TREE_OPERAND (arg0, 1));
10788 return fold_build2 (BIT_AND_EXPR, type,
10789 fold_build1 (BIT_NOT_EXPR, type, tem),
10790 fold_convert (type, arg1));
10792 /* Fold X & (X ^ Y) as X & ~Y. */
10793 if (TREE_CODE (arg1) == BIT_XOR_EXPR
10794 && operand_equal_p (arg0, TREE_OPERAND (arg1, 0), 0))
10796 tem = fold_convert (type, TREE_OPERAND (arg1, 1));
10797 return fold_build2 (BIT_AND_EXPR, type,
10798 fold_convert (type, arg0),
10799 fold_build1 (BIT_NOT_EXPR, type, tem));
10801 /* Fold X & (Y ^ X) as ~Y & X. */
10802 if (TREE_CODE (arg1) == BIT_XOR_EXPR
10803 && operand_equal_p (arg0, TREE_OPERAND (arg1, 1), 0)
10804 && reorder_operands_p (arg0, TREE_OPERAND (arg1, 0)))
10806 tem = fold_convert (type, TREE_OPERAND (arg1, 0));
10807 return fold_build2 (BIT_AND_EXPR, type,
10808 fold_build1 (BIT_NOT_EXPR, type, tem),
10809 fold_convert (type, arg0));
10812 t1 = distribute_bit_expr (code, type, arg0, arg1);
10813 if (t1 != NULL_TREE)
10815 /* Simplify ((int)c & 0377) into (int)c, if c is unsigned char. */
10816 if (TREE_CODE (arg1) == INTEGER_CST && TREE_CODE (arg0) == NOP_EXPR
10817 && TYPE_UNSIGNED (TREE_TYPE (TREE_OPERAND (arg0, 0))))
10820 = TYPE_PRECISION (TREE_TYPE (TREE_OPERAND (arg0, 0)));
10822 if (prec < BITS_PER_WORD && prec < HOST_BITS_PER_WIDE_INT
10823 && (~TREE_INT_CST_LOW (arg1)
10824 & (((HOST_WIDE_INT) 1 << prec) - 1)) == 0)
10825 return fold_convert (type, TREE_OPERAND (arg0, 0));
10828 /* Convert (and (not arg0) (not arg1)) to (not (or (arg0) (arg1))).
10830 This results in more efficient code for machines without a NOR
10831 instruction. Combine will canonicalize to the first form
10832 which will allow use of NOR instructions provided by the
10833 backend if they exist. */
10834 if (TREE_CODE (arg0) == BIT_NOT_EXPR
10835 && TREE_CODE (arg1) == BIT_NOT_EXPR)
10837 return fold_build1 (BIT_NOT_EXPR, type,
10838 build2 (BIT_IOR_EXPR, type,
10839 fold_convert (type,
10840 TREE_OPERAND (arg0, 0)),
10841 fold_convert (type,
10842 TREE_OPERAND (arg1, 0))));
10845 /* If arg0 is derived from the address of an object or function, we may
10846 be able to fold this expression using the object or function's
10848 if (POINTER_TYPE_P (TREE_TYPE (arg0)) && host_integerp (arg1, 1))
10850 unsigned HOST_WIDE_INT modulus, residue;
10851 unsigned HOST_WIDE_INT low = TREE_INT_CST_LOW (arg1);
10853 modulus = get_pointer_modulus_and_residue (arg0, &residue);
10855 /* This works because modulus is a power of 2. If this weren't the
10856 case, we'd have to replace it by its greatest power-of-2
10857 divisor: modulus & -modulus. */
10859 return build_int_cst (type, residue & low);
10862 /* Fold (X << C1) & C2 into (X << C1) & (C2 | ((1 << C1) - 1))
10863 (X >> C1) & C2 into (X >> C1) & (C2 | ~((type) -1 >> C1))
10864 if the new mask might be further optimized. */
10865 if ((TREE_CODE (arg0) == LSHIFT_EXPR
10866 || TREE_CODE (arg0) == RSHIFT_EXPR)
10867 && host_integerp (TREE_OPERAND (arg0, 1), 1)
10868 && host_integerp (arg1, TYPE_UNSIGNED (TREE_TYPE (arg1)))
10869 && tree_low_cst (TREE_OPERAND (arg0, 1), 1)
10870 < TYPE_PRECISION (TREE_TYPE (arg0))
10871 && TYPE_PRECISION (TREE_TYPE (arg0)) <= HOST_BITS_PER_WIDE_INT
10872 && tree_low_cst (TREE_OPERAND (arg0, 1), 1) > 0)
10874 unsigned int shiftc = tree_low_cst (TREE_OPERAND (arg0, 1), 1);
10875 unsigned HOST_WIDE_INT mask
10876 = tree_low_cst (arg1, TYPE_UNSIGNED (TREE_TYPE (arg1)));
10877 unsigned HOST_WIDE_INT newmask, zerobits = 0;
10878 tree shift_type = TREE_TYPE (arg0);
10880 if (TREE_CODE (arg0) == LSHIFT_EXPR)
10881 zerobits = ((((unsigned HOST_WIDE_INT) 1) << shiftc) - 1);
10882 else if (TREE_CODE (arg0) == RSHIFT_EXPR
10883 && TYPE_PRECISION (TREE_TYPE (arg0))
10884 == GET_MODE_BITSIZE (TYPE_MODE (TREE_TYPE (arg0))))
10886 unsigned int prec = TYPE_PRECISION (TREE_TYPE (arg0));
10887 tree arg00 = TREE_OPERAND (arg0, 0);
10888 /* See if more bits can be proven as zero because of
10890 if (TREE_CODE (arg00) == NOP_EXPR
10891 && TYPE_UNSIGNED (TREE_TYPE (TREE_OPERAND (arg00, 0))))
10893 tree inner_type = TREE_TYPE (TREE_OPERAND (arg00, 0));
10894 if (TYPE_PRECISION (inner_type)
10895 == GET_MODE_BITSIZE (TYPE_MODE (inner_type))
10896 && TYPE_PRECISION (inner_type) < prec)
10898 prec = TYPE_PRECISION (inner_type);
10899 /* See if we can shorten the right shift. */
10901 shift_type = inner_type;
10904 zerobits = ~(unsigned HOST_WIDE_INT) 0;
10905 zerobits >>= HOST_BITS_PER_WIDE_INT - shiftc;
10906 zerobits <<= prec - shiftc;
10907 /* For arithmetic shift if sign bit could be set, zerobits
10908 can contain actually sign bits, so no transformation is
10909 possible, unless MASK masks them all away. In that
10910 case the shift needs to be converted into logical shift. */
10911 if (!TYPE_UNSIGNED (TREE_TYPE (arg0))
10912 && prec == TYPE_PRECISION (TREE_TYPE (arg0)))
10914 if ((mask & zerobits) == 0)
10915 shift_type = unsigned_type_for (TREE_TYPE (arg0));
10921 /* ((X << 16) & 0xff00) is (X, 0). */
10922 if ((mask & zerobits) == mask)
10923 return omit_one_operand (type, build_int_cst (type, 0), arg0);
10925 newmask = mask | zerobits;
10926 if (newmask != mask && (newmask & (newmask + 1)) == 0)
10930 /* Only do the transformation if NEWMASK is some integer
10932 for (prec = BITS_PER_UNIT;
10933 prec < HOST_BITS_PER_WIDE_INT; prec <<= 1)
10934 if (newmask == (((unsigned HOST_WIDE_INT) 1) << prec) - 1)
10936 if (prec < HOST_BITS_PER_WIDE_INT
10937 || newmask == ~(unsigned HOST_WIDE_INT) 0)
10939 if (shift_type != TREE_TYPE (arg0))
10941 tem = fold_build2 (TREE_CODE (arg0), shift_type,
10942 fold_convert (shift_type,
10943 TREE_OPERAND (arg0, 0)),
10944 TREE_OPERAND (arg0, 1));
10945 tem = fold_convert (type, tem);
10949 return fold_build2 (BIT_AND_EXPR, type, tem,
10950 build_int_cst_type (TREE_TYPE (op1),
10959 /* Don't touch a floating-point divide by zero unless the mode
10960 of the constant can represent infinity. */
10961 if (TREE_CODE (arg1) == REAL_CST
10962 && !MODE_HAS_INFINITIES (TYPE_MODE (TREE_TYPE (arg1)))
10963 && real_zerop (arg1))
10966 /* Optimize A / A to 1.0 if we don't care about
10967 NaNs or Infinities. Skip the transformation
10968 for non-real operands. */
10969 if (SCALAR_FLOAT_TYPE_P (TREE_TYPE (arg0))
10970 && ! HONOR_NANS (TYPE_MODE (TREE_TYPE (arg0)))
10971 && ! HONOR_INFINITIES (TYPE_MODE (TREE_TYPE (arg0)))
10972 && operand_equal_p (arg0, arg1, 0))
10974 tree r = build_real (TREE_TYPE (arg0), dconst1);
10976 return omit_two_operands (type, r, arg0, arg1);
10979 /* The complex version of the above A / A optimization. */
10980 if (COMPLEX_FLOAT_TYPE_P (TREE_TYPE (arg0))
10981 && operand_equal_p (arg0, arg1, 0))
10983 tree elem_type = TREE_TYPE (TREE_TYPE (arg0));
10984 if (! HONOR_NANS (TYPE_MODE (elem_type))
10985 && ! HONOR_INFINITIES (TYPE_MODE (elem_type)))
10987 tree r = build_real (elem_type, dconst1);
10988 /* omit_two_operands will call fold_convert for us. */
10989 return omit_two_operands (type, r, arg0, arg1);
10993 /* (-A) / (-B) -> A / B */
10994 if (TREE_CODE (arg0) == NEGATE_EXPR && negate_expr_p (arg1))
10995 return fold_build2 (RDIV_EXPR, type,
10996 TREE_OPERAND (arg0, 0),
10997 negate_expr (arg1));
10998 if (TREE_CODE (arg1) == NEGATE_EXPR && negate_expr_p (arg0))
10999 return fold_build2 (RDIV_EXPR, type,
11000 negate_expr (arg0),
11001 TREE_OPERAND (arg1, 0));
11003 /* In IEEE floating point, x/1 is not equivalent to x for snans. */
11004 if (!HONOR_SNANS (TYPE_MODE (TREE_TYPE (arg0)))
11005 && real_onep (arg1))
11006 return non_lvalue (fold_convert (type, arg0));
11008 /* In IEEE floating point, x/-1 is not equivalent to -x for snans. */
11009 if (!HONOR_SNANS (TYPE_MODE (TREE_TYPE (arg0)))
11010 && real_minus_onep (arg1))
11011 return non_lvalue (fold_convert (type, negate_expr (arg0)));
11013 /* If ARG1 is a constant, we can convert this to a multiply by the
11014 reciprocal. This does not have the same rounding properties,
11015 so only do this if -freciprocal-math. We can actually
11016 always safely do it if ARG1 is a power of two, but it's hard to
11017 tell if it is or not in a portable manner. */
11018 if (TREE_CODE (arg1) == REAL_CST)
11020 if (flag_reciprocal_math
11021 && 0 != (tem = const_binop (code, build_real (type, dconst1),
11023 return fold_build2 (MULT_EXPR, type, arg0, tem);
11024 /* Find the reciprocal if optimizing and the result is exact. */
11028 r = TREE_REAL_CST (arg1);
11029 if (exact_real_inverse (TYPE_MODE(TREE_TYPE(arg0)), &r))
11031 tem = build_real (type, r);
11032 return fold_build2 (MULT_EXPR, type,
11033 fold_convert (type, arg0), tem);
11037 /* Convert A/B/C to A/(B*C). */
11038 if (flag_reciprocal_math
11039 && TREE_CODE (arg0) == RDIV_EXPR)
11040 return fold_build2 (RDIV_EXPR, type, TREE_OPERAND (arg0, 0),
11041 fold_build2 (MULT_EXPR, type,
11042 TREE_OPERAND (arg0, 1), arg1));
11044 /* Convert A/(B/C) to (A/B)*C. */
11045 if (flag_reciprocal_math
11046 && TREE_CODE (arg1) == RDIV_EXPR)
11047 return fold_build2 (MULT_EXPR, type,
11048 fold_build2 (RDIV_EXPR, type, arg0,
11049 TREE_OPERAND (arg1, 0)),
11050 TREE_OPERAND (arg1, 1));
11052 /* Convert C1/(X*C2) into (C1/C2)/X. */
11053 if (flag_reciprocal_math
11054 && TREE_CODE (arg1) == MULT_EXPR
11055 && TREE_CODE (arg0) == REAL_CST
11056 && TREE_CODE (TREE_OPERAND (arg1, 1)) == REAL_CST)
11058 tree tem = const_binop (RDIV_EXPR, arg0,
11059 TREE_OPERAND (arg1, 1), 0);
11061 return fold_build2 (RDIV_EXPR, type, tem,
11062 TREE_OPERAND (arg1, 0));
11065 if (flag_unsafe_math_optimizations)
11067 enum built_in_function fcode0 = builtin_mathfn_code (arg0);
11068 enum built_in_function fcode1 = builtin_mathfn_code (arg1);
11070 /* Optimize sin(x)/cos(x) as tan(x). */
11071 if (((fcode0 == BUILT_IN_SIN && fcode1 == BUILT_IN_COS)
11072 || (fcode0 == BUILT_IN_SINF && fcode1 == BUILT_IN_COSF)
11073 || (fcode0 == BUILT_IN_SINL && fcode1 == BUILT_IN_COSL))
11074 && operand_equal_p (CALL_EXPR_ARG (arg0, 0),
11075 CALL_EXPR_ARG (arg1, 0), 0))
11077 tree tanfn = mathfn_built_in (type, BUILT_IN_TAN);
11079 if (tanfn != NULL_TREE)
11080 return build_call_expr (tanfn, 1, CALL_EXPR_ARG (arg0, 0));
11083 /* Optimize cos(x)/sin(x) as 1.0/tan(x). */
11084 if (((fcode0 == BUILT_IN_COS && fcode1 == BUILT_IN_SIN)
11085 || (fcode0 == BUILT_IN_COSF && fcode1 == BUILT_IN_SINF)
11086 || (fcode0 == BUILT_IN_COSL && fcode1 == BUILT_IN_SINL))
11087 && operand_equal_p (CALL_EXPR_ARG (arg0, 0),
11088 CALL_EXPR_ARG (arg1, 0), 0))
11090 tree tanfn = mathfn_built_in (type, BUILT_IN_TAN);
11092 if (tanfn != NULL_TREE)
11094 tree tmp = build_call_expr (tanfn, 1, CALL_EXPR_ARG (arg0, 0));
11095 return fold_build2 (RDIV_EXPR, type,
11096 build_real (type, dconst1), tmp);
11100 /* Optimize sin(x)/tan(x) as cos(x) if we don't care about
11101 NaNs or Infinities. */
11102 if (((fcode0 == BUILT_IN_SIN && fcode1 == BUILT_IN_TAN)
11103 || (fcode0 == BUILT_IN_SINF && fcode1 == BUILT_IN_TANF)
11104 || (fcode0 == BUILT_IN_SINL && fcode1 == BUILT_IN_TANL)))
11106 tree arg00 = CALL_EXPR_ARG (arg0, 0);
11107 tree arg01 = CALL_EXPR_ARG (arg1, 0);
11109 if (! HONOR_NANS (TYPE_MODE (TREE_TYPE (arg00)))
11110 && ! HONOR_INFINITIES (TYPE_MODE (TREE_TYPE (arg00)))
11111 && operand_equal_p (arg00, arg01, 0))
11113 tree cosfn = mathfn_built_in (type, BUILT_IN_COS);
11115 if (cosfn != NULL_TREE)
11116 return build_call_expr (cosfn, 1, arg00);
11120 /* Optimize tan(x)/sin(x) as 1.0/cos(x) if we don't care about
11121 NaNs or Infinities. */
11122 if (((fcode0 == BUILT_IN_TAN && fcode1 == BUILT_IN_SIN)
11123 || (fcode0 == BUILT_IN_TANF && fcode1 == BUILT_IN_SINF)
11124 || (fcode0 == BUILT_IN_TANL && fcode1 == BUILT_IN_SINL)))
11126 tree arg00 = CALL_EXPR_ARG (arg0, 0);
11127 tree arg01 = CALL_EXPR_ARG (arg1, 0);
11129 if (! HONOR_NANS (TYPE_MODE (TREE_TYPE (arg00)))
11130 && ! HONOR_INFINITIES (TYPE_MODE (TREE_TYPE (arg00)))
11131 && operand_equal_p (arg00, arg01, 0))
11133 tree cosfn = mathfn_built_in (type, BUILT_IN_COS);
11135 if (cosfn != NULL_TREE)
11137 tree tmp = build_call_expr (cosfn, 1, arg00);
11138 return fold_build2 (RDIV_EXPR, type,
11139 build_real (type, dconst1),
11145 /* Optimize pow(x,c)/x as pow(x,c-1). */
11146 if (fcode0 == BUILT_IN_POW
11147 || fcode0 == BUILT_IN_POWF
11148 || fcode0 == BUILT_IN_POWL)
11150 tree arg00 = CALL_EXPR_ARG (arg0, 0);
11151 tree arg01 = CALL_EXPR_ARG (arg0, 1);
11152 if (TREE_CODE (arg01) == REAL_CST
11153 && !TREE_OVERFLOW (arg01)
11154 && operand_equal_p (arg1, arg00, 0))
11156 tree powfn = TREE_OPERAND (CALL_EXPR_FN (arg0), 0);
11160 c = TREE_REAL_CST (arg01);
11161 real_arithmetic (&c, MINUS_EXPR, &c, &dconst1);
11162 arg = build_real (type, c);
11163 return build_call_expr (powfn, 2, arg1, arg);
11167 /* Optimize a/root(b/c) into a*root(c/b). */
11168 if (BUILTIN_ROOT_P (fcode1))
11170 tree rootarg = CALL_EXPR_ARG (arg1, 0);
11172 if (TREE_CODE (rootarg) == RDIV_EXPR)
11174 tree rootfn = TREE_OPERAND (CALL_EXPR_FN (arg1), 0);
11175 tree b = TREE_OPERAND (rootarg, 0);
11176 tree c = TREE_OPERAND (rootarg, 1);
11178 tree tmp = fold_build2 (RDIV_EXPR, type, c, b);
11180 tmp = build_call_expr (rootfn, 1, tmp);
11181 return fold_build2 (MULT_EXPR, type, arg0, tmp);
11185 /* Optimize x/expN(y) into x*expN(-y). */
11186 if (BUILTIN_EXPONENT_P (fcode1))
11188 tree expfn = TREE_OPERAND (CALL_EXPR_FN (arg1), 0);
11189 tree arg = negate_expr (CALL_EXPR_ARG (arg1, 0));
11190 arg1 = build_call_expr (expfn, 1, fold_convert (type, arg));
11191 return fold_build2 (MULT_EXPR, type, arg0, arg1);
11194 /* Optimize x/pow(y,z) into x*pow(y,-z). */
11195 if (fcode1 == BUILT_IN_POW
11196 || fcode1 == BUILT_IN_POWF
11197 || fcode1 == BUILT_IN_POWL)
11199 tree powfn = TREE_OPERAND (CALL_EXPR_FN (arg1), 0);
11200 tree arg10 = CALL_EXPR_ARG (arg1, 0);
11201 tree arg11 = CALL_EXPR_ARG (arg1, 1);
11202 tree neg11 = fold_convert (type, negate_expr (arg11));
11203 arg1 = build_call_expr (powfn, 2, arg10, neg11);
11204 return fold_build2 (MULT_EXPR, type, arg0, arg1);
11209 case TRUNC_DIV_EXPR:
11210 case FLOOR_DIV_EXPR:
11211 /* Simplify A / (B << N) where A and B are positive and B is
11212 a power of 2, to A >> (N + log2(B)). */
11213 strict_overflow_p = false;
11214 if (TREE_CODE (arg1) == LSHIFT_EXPR
11215 && (TYPE_UNSIGNED (type)
11216 || tree_expr_nonnegative_warnv_p (op0, &strict_overflow_p)))
11218 tree sval = TREE_OPERAND (arg1, 0);
11219 if (integer_pow2p (sval) && tree_int_cst_sgn (sval) > 0)
11221 tree sh_cnt = TREE_OPERAND (arg1, 1);
11222 unsigned long pow2 = exact_log2 (TREE_INT_CST_LOW (sval));
11224 if (strict_overflow_p)
11225 fold_overflow_warning (("assuming signed overflow does not "
11226 "occur when simplifying A / (B << N)"),
11227 WARN_STRICT_OVERFLOW_MISC);
11229 sh_cnt = fold_build2 (PLUS_EXPR, TREE_TYPE (sh_cnt),
11230 sh_cnt, build_int_cst (NULL_TREE, pow2));
11231 return fold_build2 (RSHIFT_EXPR, type,
11232 fold_convert (type, arg0), sh_cnt);
11236 /* For unsigned integral types, FLOOR_DIV_EXPR is the same as
11237 TRUNC_DIV_EXPR. Rewrite into the latter in this case. */
11238 if (INTEGRAL_TYPE_P (type)
11239 && TYPE_UNSIGNED (type)
11240 && code == FLOOR_DIV_EXPR)
11241 return fold_build2 (TRUNC_DIV_EXPR, type, op0, op1);
11245 case ROUND_DIV_EXPR:
11246 case CEIL_DIV_EXPR:
11247 case EXACT_DIV_EXPR:
11248 if (integer_onep (arg1))
11249 return non_lvalue (fold_convert (type, arg0));
11250 if (integer_zerop (arg1))
11252 /* X / -1 is -X. */
11253 if (!TYPE_UNSIGNED (type)
11254 && TREE_CODE (arg1) == INTEGER_CST
11255 && TREE_INT_CST_LOW (arg1) == (unsigned HOST_WIDE_INT) -1
11256 && TREE_INT_CST_HIGH (arg1) == -1)
11257 return fold_convert (type, negate_expr (arg0));
11259 /* Convert -A / -B to A / B when the type is signed and overflow is
11261 if ((!INTEGRAL_TYPE_P (type) || TYPE_OVERFLOW_UNDEFINED (type))
11262 && TREE_CODE (arg0) == NEGATE_EXPR
11263 && negate_expr_p (arg1))
11265 if (INTEGRAL_TYPE_P (type))
11266 fold_overflow_warning (("assuming signed overflow does not occur "
11267 "when distributing negation across "
11269 WARN_STRICT_OVERFLOW_MISC);
11270 return fold_build2 (code, type,
11271 fold_convert (type, TREE_OPERAND (arg0, 0)),
11272 negate_expr (arg1));
11274 if ((!INTEGRAL_TYPE_P (type) || TYPE_OVERFLOW_UNDEFINED (type))
11275 && TREE_CODE (arg1) == NEGATE_EXPR
11276 && negate_expr_p (arg0))
11278 if (INTEGRAL_TYPE_P (type))
11279 fold_overflow_warning (("assuming signed overflow does not occur "
11280 "when distributing negation across "
11282 WARN_STRICT_OVERFLOW_MISC);
11283 return fold_build2 (code, type, negate_expr (arg0),
11284 TREE_OPERAND (arg1, 0));
11287 /* If arg0 is a multiple of arg1, then rewrite to the fastest div
11288 operation, EXACT_DIV_EXPR.
11290 Note that only CEIL_DIV_EXPR and FLOOR_DIV_EXPR are rewritten now.
11291 At one time others generated faster code, it's not clear if they do
11292 after the last round to changes to the DIV code in expmed.c. */
11293 if ((code == CEIL_DIV_EXPR || code == FLOOR_DIV_EXPR)
11294 && multiple_of_p (type, arg0, arg1))
11295 return fold_build2 (EXACT_DIV_EXPR, type, arg0, arg1);
11297 strict_overflow_p = false;
11298 if (TREE_CODE (arg1) == INTEGER_CST
11299 && 0 != (tem = extract_muldiv (op0, arg1, code, NULL_TREE,
11300 &strict_overflow_p)))
11302 if (strict_overflow_p)
11303 fold_overflow_warning (("assuming signed overflow does not occur "
11304 "when simplifying division"),
11305 WARN_STRICT_OVERFLOW_MISC);
11306 return fold_convert (type, tem);
11311 case CEIL_MOD_EXPR:
11312 case FLOOR_MOD_EXPR:
11313 case ROUND_MOD_EXPR:
11314 case TRUNC_MOD_EXPR:
11315 /* X % 1 is always zero, but be sure to preserve any side
11317 if (integer_onep (arg1))
11318 return omit_one_operand (type, integer_zero_node, arg0);
11320 /* X % 0, return X % 0 unchanged so that we can get the
11321 proper warnings and errors. */
11322 if (integer_zerop (arg1))
11325 /* 0 % X is always zero, but be sure to preserve any side
11326 effects in X. Place this after checking for X == 0. */
11327 if (integer_zerop (arg0))
11328 return omit_one_operand (type, integer_zero_node, arg1);
11330 /* X % -1 is zero. */
11331 if (!TYPE_UNSIGNED (type)
11332 && TREE_CODE (arg1) == INTEGER_CST
11333 && TREE_INT_CST_LOW (arg1) == (unsigned HOST_WIDE_INT) -1
11334 && TREE_INT_CST_HIGH (arg1) == -1)
11335 return omit_one_operand (type, integer_zero_node, arg0);
11337 /* Optimize TRUNC_MOD_EXPR by a power of two into a BIT_AND_EXPR,
11338 i.e. "X % C" into "X & (C - 1)", if X and C are positive. */
11339 strict_overflow_p = false;
11340 if ((code == TRUNC_MOD_EXPR || code == FLOOR_MOD_EXPR)
11341 && (TYPE_UNSIGNED (type)
11342 || tree_expr_nonnegative_warnv_p (op0, &strict_overflow_p)))
11345 /* Also optimize A % (C << N) where C is a power of 2,
11346 to A & ((C << N) - 1). */
11347 if (TREE_CODE (arg1) == LSHIFT_EXPR)
11348 c = TREE_OPERAND (arg1, 0);
11350 if (integer_pow2p (c) && tree_int_cst_sgn (c) > 0)
11352 tree mask = fold_build2 (MINUS_EXPR, TREE_TYPE (arg1), arg1,
11353 build_int_cst (TREE_TYPE (arg1), 1));
11354 if (strict_overflow_p)
11355 fold_overflow_warning (("assuming signed overflow does not "
11356 "occur when simplifying "
11357 "X % (power of two)"),
11358 WARN_STRICT_OVERFLOW_MISC);
11359 return fold_build2 (BIT_AND_EXPR, type,
11360 fold_convert (type, arg0),
11361 fold_convert (type, mask));
11365 /* X % -C is the same as X % C. */
11366 if (code == TRUNC_MOD_EXPR
11367 && !TYPE_UNSIGNED (type)
11368 && TREE_CODE (arg1) == INTEGER_CST
11369 && !TREE_OVERFLOW (arg1)
11370 && TREE_INT_CST_HIGH (arg1) < 0
11371 && !TYPE_OVERFLOW_TRAPS (type)
11372 /* Avoid this transformation if C is INT_MIN, i.e. C == -C. */
11373 && !sign_bit_p (arg1, arg1))
11374 return fold_build2 (code, type, fold_convert (type, arg0),
11375 fold_convert (type, negate_expr (arg1)));
11377 /* X % -Y is the same as X % Y. */
11378 if (code == TRUNC_MOD_EXPR
11379 && !TYPE_UNSIGNED (type)
11380 && TREE_CODE (arg1) == NEGATE_EXPR
11381 && !TYPE_OVERFLOW_TRAPS (type))
11382 return fold_build2 (code, type, fold_convert (type, arg0),
11383 fold_convert (type, TREE_OPERAND (arg1, 0)));
11385 if (TREE_CODE (arg1) == INTEGER_CST
11386 && 0 != (tem = extract_muldiv (op0, arg1, code, NULL_TREE,
11387 &strict_overflow_p)))
11389 if (strict_overflow_p)
11390 fold_overflow_warning (("assuming signed overflow does not occur "
11391 "when simplifying modulos"),
11392 WARN_STRICT_OVERFLOW_MISC);
11393 return fold_convert (type, tem);
11400 if (integer_all_onesp (arg0))
11401 return omit_one_operand (type, arg0, arg1);
11405 /* Optimize -1 >> x for arithmetic right shifts. */
11406 if (integer_all_onesp (arg0) && !TYPE_UNSIGNED (type))
11407 return omit_one_operand (type, arg0, arg1);
11408 /* ... fall through ... */
11412 if (integer_zerop (arg1))
11413 return non_lvalue (fold_convert (type, arg0));
11414 if (integer_zerop (arg0))
11415 return omit_one_operand (type, arg0, arg1);
11417 /* Since negative shift count is not well-defined,
11418 don't try to compute it in the compiler. */
11419 if (TREE_CODE (arg1) == INTEGER_CST && tree_int_cst_sgn (arg1) < 0)
11422 /* Turn (a OP c1) OP c2 into a OP (c1+c2). */
11423 if (TREE_CODE (op0) == code && host_integerp (arg1, false)
11424 && TREE_INT_CST_LOW (arg1) < TYPE_PRECISION (type)
11425 && host_integerp (TREE_OPERAND (arg0, 1), false)
11426 && TREE_INT_CST_LOW (TREE_OPERAND (arg0, 1)) < TYPE_PRECISION (type))
11428 HOST_WIDE_INT low = (TREE_INT_CST_LOW (TREE_OPERAND (arg0, 1))
11429 + TREE_INT_CST_LOW (arg1));
11431 /* Deal with a OP (c1 + c2) being undefined but (a OP c1) OP c2
11432 being well defined. */
11433 if (low >= TYPE_PRECISION (type))
11435 if (code == LROTATE_EXPR || code == RROTATE_EXPR)
11436 low = low % TYPE_PRECISION (type);
11437 else if (TYPE_UNSIGNED (type) || code == LSHIFT_EXPR)
11438 return build_int_cst (type, 0);
11440 low = TYPE_PRECISION (type) - 1;
11443 return fold_build2 (code, type, TREE_OPERAND (arg0, 0),
11444 build_int_cst (type, low));
11447 /* Transform (x >> c) << c into x & (-1<<c), or transform (x << c) >> c
11448 into x & ((unsigned)-1 >> c) for unsigned types. */
11449 if (((code == LSHIFT_EXPR && TREE_CODE (arg0) == RSHIFT_EXPR)
11450 || (TYPE_UNSIGNED (type)
11451 && code == RSHIFT_EXPR && TREE_CODE (arg0) == LSHIFT_EXPR))
11452 && host_integerp (arg1, false)
11453 && TREE_INT_CST_LOW (arg1) < TYPE_PRECISION (type)
11454 && host_integerp (TREE_OPERAND (arg0, 1), false)
11455 && TREE_INT_CST_LOW (TREE_OPERAND (arg0, 1)) < TYPE_PRECISION (type))
11457 HOST_WIDE_INT low0 = TREE_INT_CST_LOW (TREE_OPERAND (arg0, 1));
11458 HOST_WIDE_INT low1 = TREE_INT_CST_LOW (arg1);
11464 arg00 = fold_convert (type, TREE_OPERAND (arg0, 0));
11466 lshift = build_int_cst (type, -1);
11467 lshift = int_const_binop (code, lshift, arg1, 0);
11469 return fold_build2 (BIT_AND_EXPR, type, arg00, lshift);
11473 /* Rewrite an LROTATE_EXPR by a constant into an
11474 RROTATE_EXPR by a new constant. */
11475 if (code == LROTATE_EXPR && TREE_CODE (arg1) == INTEGER_CST)
11477 tree tem = build_int_cst (TREE_TYPE (arg1),
11478 TYPE_PRECISION (type));
11479 tem = const_binop (MINUS_EXPR, tem, arg1, 0);
11480 return fold_build2 (RROTATE_EXPR, type, op0, tem);
11483 /* If we have a rotate of a bit operation with the rotate count and
11484 the second operand of the bit operation both constant,
11485 permute the two operations. */
11486 if (code == RROTATE_EXPR && TREE_CODE (arg1) == INTEGER_CST
11487 && (TREE_CODE (arg0) == BIT_AND_EXPR
11488 || TREE_CODE (arg0) == BIT_IOR_EXPR
11489 || TREE_CODE (arg0) == BIT_XOR_EXPR)
11490 && TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST)
11491 return fold_build2 (TREE_CODE (arg0), type,
11492 fold_build2 (code, type,
11493 TREE_OPERAND (arg0, 0), arg1),
11494 fold_build2 (code, type,
11495 TREE_OPERAND (arg0, 1), arg1));
11497 /* Two consecutive rotates adding up to the precision of the
11498 type can be ignored. */
11499 if (code == RROTATE_EXPR && TREE_CODE (arg1) == INTEGER_CST
11500 && TREE_CODE (arg0) == RROTATE_EXPR
11501 && TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST
11502 && TREE_INT_CST_HIGH (arg1) == 0
11503 && TREE_INT_CST_HIGH (TREE_OPERAND (arg0, 1)) == 0
11504 && ((TREE_INT_CST_LOW (arg1)
11505 + TREE_INT_CST_LOW (TREE_OPERAND (arg0, 1)))
11506 == (unsigned int) TYPE_PRECISION (type)))
11507 return TREE_OPERAND (arg0, 0);
11509 /* Fold (X & C2) << C1 into (X << C1) & (C2 << C1)
11510 (X & C2) >> C1 into (X >> C1) & (C2 >> C1)
11511 if the latter can be further optimized. */
11512 if ((code == LSHIFT_EXPR || code == RSHIFT_EXPR)
11513 && TREE_CODE (arg0) == BIT_AND_EXPR
11514 && TREE_CODE (arg1) == INTEGER_CST
11515 && TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST)
11517 tree mask = fold_build2 (code, type,
11518 fold_convert (type, TREE_OPERAND (arg0, 1)),
11520 tree shift = fold_build2 (code, type,
11521 fold_convert (type, TREE_OPERAND (arg0, 0)),
11523 tem = fold_binary (BIT_AND_EXPR, type, shift, mask);
11531 if (operand_equal_p (arg0, arg1, 0))
11532 return omit_one_operand (type, arg0, arg1);
11533 if (INTEGRAL_TYPE_P (type)
11534 && operand_equal_p (arg1, TYPE_MIN_VALUE (type), OEP_ONLY_CONST))
11535 return omit_one_operand (type, arg1, arg0);
11536 tem = fold_minmax (MIN_EXPR, type, arg0, arg1);
11542 if (operand_equal_p (arg0, arg1, 0))
11543 return omit_one_operand (type, arg0, arg1);
11544 if (INTEGRAL_TYPE_P (type)
11545 && TYPE_MAX_VALUE (type)
11546 && operand_equal_p (arg1, TYPE_MAX_VALUE (type), OEP_ONLY_CONST))
11547 return omit_one_operand (type, arg1, arg0);
11548 tem = fold_minmax (MAX_EXPR, type, arg0, arg1);
11553 case TRUTH_ANDIF_EXPR:
11554 /* Note that the operands of this must be ints
11555 and their values must be 0 or 1.
11556 ("true" is a fixed value perhaps depending on the language.) */
11557 /* If first arg is constant zero, return it. */
11558 if (integer_zerop (arg0))
11559 return fold_convert (type, arg0);
11560 case TRUTH_AND_EXPR:
11561 /* If either arg is constant true, drop it. */
11562 if (TREE_CODE (arg0) == INTEGER_CST && ! integer_zerop (arg0))
11563 return non_lvalue (fold_convert (type, arg1));
11564 if (TREE_CODE (arg1) == INTEGER_CST && ! integer_zerop (arg1)
11565 /* Preserve sequence points. */
11566 && (code != TRUTH_ANDIF_EXPR || ! TREE_SIDE_EFFECTS (arg0)))
11567 return non_lvalue (fold_convert (type, arg0));
11568 /* If second arg is constant zero, result is zero, but first arg
11569 must be evaluated. */
11570 if (integer_zerop (arg1))
11571 return omit_one_operand (type, arg1, arg0);
11572 /* Likewise for first arg, but note that only the TRUTH_AND_EXPR
11573 case will be handled here. */
11574 if (integer_zerop (arg0))
11575 return omit_one_operand (type, arg0, arg1);
11577 /* !X && X is always false. */
11578 if (TREE_CODE (arg0) == TRUTH_NOT_EXPR
11579 && operand_equal_p (TREE_OPERAND (arg0, 0), arg1, 0))
11580 return omit_one_operand (type, integer_zero_node, arg1);
11581 /* X && !X is always false. */
11582 if (TREE_CODE (arg1) == TRUTH_NOT_EXPR
11583 && operand_equal_p (arg0, TREE_OPERAND (arg1, 0), 0))
11584 return omit_one_operand (type, integer_zero_node, arg0);
11586 /* A < X && A + 1 > Y ==> A < X && A >= Y. Normally A + 1 > Y
11587 means A >= Y && A != MAX, but in this case we know that
11590 if (!TREE_SIDE_EFFECTS (arg0)
11591 && !TREE_SIDE_EFFECTS (arg1))
11593 tem = fold_to_nonsharp_ineq_using_bound (arg0, arg1);
11594 if (tem && !operand_equal_p (tem, arg0, 0))
11595 return fold_build2 (code, type, tem, arg1);
11597 tem = fold_to_nonsharp_ineq_using_bound (arg1, arg0);
11598 if (tem && !operand_equal_p (tem, arg1, 0))
11599 return fold_build2 (code, type, arg0, tem);
11603 /* We only do these simplifications if we are optimizing. */
11607 /* Check for things like (A || B) && (A || C). We can convert this
11608 to A || (B && C). Note that either operator can be any of the four
11609 truth and/or operations and the transformation will still be
11610 valid. Also note that we only care about order for the
11611 ANDIF and ORIF operators. If B contains side effects, this
11612 might change the truth-value of A. */
11613 if (TREE_CODE (arg0) == TREE_CODE (arg1)
11614 && (TREE_CODE (arg0) == TRUTH_ANDIF_EXPR
11615 || TREE_CODE (arg0) == TRUTH_ORIF_EXPR
11616 || TREE_CODE (arg0) == TRUTH_AND_EXPR
11617 || TREE_CODE (arg0) == TRUTH_OR_EXPR)
11618 && ! TREE_SIDE_EFFECTS (TREE_OPERAND (arg0, 1)))
11620 tree a00 = TREE_OPERAND (arg0, 0);
11621 tree a01 = TREE_OPERAND (arg0, 1);
11622 tree a10 = TREE_OPERAND (arg1, 0);
11623 tree a11 = TREE_OPERAND (arg1, 1);
11624 int commutative = ((TREE_CODE (arg0) == TRUTH_OR_EXPR
11625 || TREE_CODE (arg0) == TRUTH_AND_EXPR)
11626 && (code == TRUTH_AND_EXPR
11627 || code == TRUTH_OR_EXPR));
11629 if (operand_equal_p (a00, a10, 0))
11630 return fold_build2 (TREE_CODE (arg0), type, a00,
11631 fold_build2 (code, type, a01, a11));
11632 else if (commutative && operand_equal_p (a00, a11, 0))
11633 return fold_build2 (TREE_CODE (arg0), type, a00,
11634 fold_build2 (code, type, a01, a10));
11635 else if (commutative && operand_equal_p (a01, a10, 0))
11636 return fold_build2 (TREE_CODE (arg0), type, a01,
11637 fold_build2 (code, type, a00, a11));
11639 /* This case if tricky because we must either have commutative
11640 operators or else A10 must not have side-effects. */
11642 else if ((commutative || ! TREE_SIDE_EFFECTS (a10))
11643 && operand_equal_p (a01, a11, 0))
11644 return fold_build2 (TREE_CODE (arg0), type,
11645 fold_build2 (code, type, a00, a10),
11649 /* See if we can build a range comparison. */
11650 if (0 != (tem = fold_range_test (code, type, op0, op1)))
11653 /* Check for the possibility of merging component references. If our
11654 lhs is another similar operation, try to merge its rhs with our
11655 rhs. Then try to merge our lhs and rhs. */
11656 if (TREE_CODE (arg0) == code
11657 && 0 != (tem = fold_truthop (code, type,
11658 TREE_OPERAND (arg0, 1), arg1)))
11659 return fold_build2 (code, type, TREE_OPERAND (arg0, 0), tem);
11661 if ((tem = fold_truthop (code, type, arg0, arg1)) != 0)
11666 case TRUTH_ORIF_EXPR:
11667 /* Note that the operands of this must be ints
11668 and their values must be 0 or true.
11669 ("true" is a fixed value perhaps depending on the language.) */
11670 /* If first arg is constant true, return it. */
11671 if (TREE_CODE (arg0) == INTEGER_CST && ! integer_zerop (arg0))
11672 return fold_convert (type, arg0);
11673 case TRUTH_OR_EXPR:
11674 /* If either arg is constant zero, drop it. */
11675 if (TREE_CODE (arg0) == INTEGER_CST && integer_zerop (arg0))
11676 return non_lvalue (fold_convert (type, arg1));
11677 if (TREE_CODE (arg1) == INTEGER_CST && integer_zerop (arg1)
11678 /* Preserve sequence points. */
11679 && (code != TRUTH_ORIF_EXPR || ! TREE_SIDE_EFFECTS (arg0)))
11680 return non_lvalue (fold_convert (type, arg0));
11681 /* If second arg is constant true, result is true, but we must
11682 evaluate first arg. */
11683 if (TREE_CODE (arg1) == INTEGER_CST && ! integer_zerop (arg1))
11684 return omit_one_operand (type, arg1, arg0);
11685 /* Likewise for first arg, but note this only occurs here for
11687 if (TREE_CODE (arg0) == INTEGER_CST && ! integer_zerop (arg0))
11688 return omit_one_operand (type, arg0, arg1);
11690 /* !X || X is always true. */
11691 if (TREE_CODE (arg0) == TRUTH_NOT_EXPR
11692 && operand_equal_p (TREE_OPERAND (arg0, 0), arg1, 0))
11693 return omit_one_operand (type, integer_one_node, arg1);
11694 /* X || !X is always true. */
11695 if (TREE_CODE (arg1) == TRUTH_NOT_EXPR
11696 && operand_equal_p (arg0, TREE_OPERAND (arg1, 0), 0))
11697 return omit_one_operand (type, integer_one_node, arg0);
11701 case TRUTH_XOR_EXPR:
11702 /* If the second arg is constant zero, drop it. */
11703 if (integer_zerop (arg1))
11704 return non_lvalue (fold_convert (type, arg0));
11705 /* If the second arg is constant true, this is a logical inversion. */
11706 if (integer_onep (arg1))
11708 /* Only call invert_truthvalue if operand is a truth value. */
11709 if (TREE_CODE (TREE_TYPE (arg0)) != BOOLEAN_TYPE)
11710 tem = fold_build1 (TRUTH_NOT_EXPR, TREE_TYPE (arg0), arg0);
11712 tem = invert_truthvalue (arg0);
11713 return non_lvalue (fold_convert (type, tem));
11715 /* Identical arguments cancel to zero. */
11716 if (operand_equal_p (arg0, arg1, 0))
11717 return omit_one_operand (type, integer_zero_node, arg0);
11719 /* !X ^ X is always true. */
11720 if (TREE_CODE (arg0) == TRUTH_NOT_EXPR
11721 && operand_equal_p (TREE_OPERAND (arg0, 0), arg1, 0))
11722 return omit_one_operand (type, integer_one_node, arg1);
11724 /* X ^ !X is always true. */
11725 if (TREE_CODE (arg1) == TRUTH_NOT_EXPR
11726 && operand_equal_p (arg0, TREE_OPERAND (arg1, 0), 0))
11727 return omit_one_operand (type, integer_one_node, arg0);
11733 tem = fold_comparison (code, type, op0, op1);
11734 if (tem != NULL_TREE)
11737 /* bool_var != 0 becomes bool_var. */
11738 if (TREE_CODE (TREE_TYPE (arg0)) == BOOLEAN_TYPE && integer_zerop (arg1)
11739 && code == NE_EXPR)
11740 return non_lvalue (fold_convert (type, arg0));
11742 /* bool_var == 1 becomes bool_var. */
11743 if (TREE_CODE (TREE_TYPE (arg0)) == BOOLEAN_TYPE && integer_onep (arg1)
11744 && code == EQ_EXPR)
11745 return non_lvalue (fold_convert (type, arg0));
11747 /* bool_var != 1 becomes !bool_var. */
11748 if (TREE_CODE (TREE_TYPE (arg0)) == BOOLEAN_TYPE && integer_onep (arg1)
11749 && code == NE_EXPR)
11750 return fold_build1 (TRUTH_NOT_EXPR, type, fold_convert (type, arg0));
11752 /* bool_var == 0 becomes !bool_var. */
11753 if (TREE_CODE (TREE_TYPE (arg0)) == BOOLEAN_TYPE && integer_zerop (arg1)
11754 && code == EQ_EXPR)
11755 return fold_build1 (TRUTH_NOT_EXPR, type, fold_convert (type, arg0));
11757 /* If this is an equality comparison of the address of two non-weak,
11758 unaliased symbols neither of which are extern (since we do not
11759 have access to attributes for externs), then we know the result. */
11760 if (TREE_CODE (arg0) == ADDR_EXPR
11761 && VAR_OR_FUNCTION_DECL_P (TREE_OPERAND (arg0, 0))
11762 && ! DECL_WEAK (TREE_OPERAND (arg0, 0))
11763 && ! lookup_attribute ("alias",
11764 DECL_ATTRIBUTES (TREE_OPERAND (arg0, 0)))
11765 && ! DECL_EXTERNAL (TREE_OPERAND (arg0, 0))
11766 && TREE_CODE (arg1) == ADDR_EXPR
11767 && VAR_OR_FUNCTION_DECL_P (TREE_OPERAND (arg1, 0))
11768 && ! DECL_WEAK (TREE_OPERAND (arg1, 0))
11769 && ! lookup_attribute ("alias",
11770 DECL_ATTRIBUTES (TREE_OPERAND (arg1, 0)))
11771 && ! DECL_EXTERNAL (TREE_OPERAND (arg1, 0)))
11773 /* We know that we're looking at the address of two
11774 non-weak, unaliased, static _DECL nodes.
11776 It is both wasteful and incorrect to call operand_equal_p
11777 to compare the two ADDR_EXPR nodes. It is wasteful in that
11778 all we need to do is test pointer equality for the arguments
11779 to the two ADDR_EXPR nodes. It is incorrect to use
11780 operand_equal_p as that function is NOT equivalent to a
11781 C equality test. It can in fact return false for two
11782 objects which would test as equal using the C equality
11784 bool equal = TREE_OPERAND (arg0, 0) == TREE_OPERAND (arg1, 0);
11785 return constant_boolean_node (equal
11786 ? code == EQ_EXPR : code != EQ_EXPR,
11790 /* If this is an EQ or NE comparison of a constant with a PLUS_EXPR or
11791 a MINUS_EXPR of a constant, we can convert it into a comparison with
11792 a revised constant as long as no overflow occurs. */
11793 if (TREE_CODE (arg1) == INTEGER_CST
11794 && (TREE_CODE (arg0) == PLUS_EXPR
11795 || TREE_CODE (arg0) == MINUS_EXPR)
11796 && TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST
11797 && 0 != (tem = const_binop (TREE_CODE (arg0) == PLUS_EXPR
11798 ? MINUS_EXPR : PLUS_EXPR,
11799 fold_convert (TREE_TYPE (arg0), arg1),
11800 TREE_OPERAND (arg0, 1), 0))
11801 && !TREE_OVERFLOW (tem))
11802 return fold_build2 (code, type, TREE_OPERAND (arg0, 0), tem);
11804 /* Similarly for a NEGATE_EXPR. */
11805 if (TREE_CODE (arg0) == NEGATE_EXPR
11806 && TREE_CODE (arg1) == INTEGER_CST
11807 && 0 != (tem = negate_expr (arg1))
11808 && TREE_CODE (tem) == INTEGER_CST
11809 && !TREE_OVERFLOW (tem))
11810 return fold_build2 (code, type, TREE_OPERAND (arg0, 0), tem);
11812 /* Similarly for a BIT_XOR_EXPR; X ^ C1 == C2 is X == (C1 ^ C2). */
11813 if (TREE_CODE (arg0) == BIT_XOR_EXPR
11814 && TREE_CODE (arg1) == INTEGER_CST
11815 && TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST)
11816 return fold_build2 (code, type, TREE_OPERAND (arg0, 0),
11817 fold_build2 (BIT_XOR_EXPR, TREE_TYPE (arg0),
11818 fold_convert (TREE_TYPE (arg0), arg1),
11819 TREE_OPERAND (arg0, 1)));
11821 /* Transform comparisons of the form X +- C CMP X. */
11822 if ((TREE_CODE (arg0) == PLUS_EXPR || TREE_CODE (arg0) == MINUS_EXPR)
11823 && operand_equal_p (TREE_OPERAND (arg0, 0), arg1, 0)
11824 && TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST
11825 && (INTEGRAL_TYPE_P (TREE_TYPE (arg0))
11826 || POINTER_TYPE_P (TREE_TYPE (arg0))))
11828 tree cst = TREE_OPERAND (arg0, 1);
11830 if (code == EQ_EXPR
11831 && !integer_zerop (cst))
11832 return omit_two_operands (type, boolean_false_node,
11833 TREE_OPERAND (arg0, 0), arg1);
11835 return omit_two_operands (type, boolean_true_node,
11836 TREE_OPERAND (arg0, 0), arg1);
11839 /* If we have X - Y == 0, we can convert that to X == Y and similarly
11840 for !=. Don't do this for ordered comparisons due to overflow. */
11841 if (TREE_CODE (arg0) == MINUS_EXPR
11842 && integer_zerop (arg1))
11843 return fold_build2 (code, type,
11844 TREE_OPERAND (arg0, 0), TREE_OPERAND (arg0, 1));
11846 /* Convert ABS_EXPR<x> == 0 or ABS_EXPR<x> != 0 to x == 0 or x != 0. */
11847 if (TREE_CODE (arg0) == ABS_EXPR
11848 && (integer_zerop (arg1) || real_zerop (arg1)))
11849 return fold_build2 (code, type, TREE_OPERAND (arg0, 0), arg1);
11851 /* If this is an EQ or NE comparison with zero and ARG0 is
11852 (1 << foo) & bar, convert it to (bar >> foo) & 1. Both require
11853 two operations, but the latter can be done in one less insn
11854 on machines that have only two-operand insns or on which a
11855 constant cannot be the first operand. */
11856 if (TREE_CODE (arg0) == BIT_AND_EXPR
11857 && integer_zerop (arg1))
11859 tree arg00 = TREE_OPERAND (arg0, 0);
11860 tree arg01 = TREE_OPERAND (arg0, 1);
11861 if (TREE_CODE (arg00) == LSHIFT_EXPR
11862 && integer_onep (TREE_OPERAND (arg00, 0)))
11864 tree tem = fold_build2 (RSHIFT_EXPR, TREE_TYPE (arg00),
11865 arg01, TREE_OPERAND (arg00, 1));
11866 tem = fold_build2 (BIT_AND_EXPR, TREE_TYPE (arg0), tem,
11867 build_int_cst (TREE_TYPE (arg0), 1));
11868 return fold_build2 (code, type,
11869 fold_convert (TREE_TYPE (arg1), tem), arg1);
11871 else if (TREE_CODE (arg01) == LSHIFT_EXPR
11872 && integer_onep (TREE_OPERAND (arg01, 0)))
11874 tree tem = fold_build2 (RSHIFT_EXPR, TREE_TYPE (arg01),
11875 arg00, TREE_OPERAND (arg01, 1));
11876 tem = fold_build2 (BIT_AND_EXPR, TREE_TYPE (arg0), tem,
11877 build_int_cst (TREE_TYPE (arg0), 1));
11878 return fold_build2 (code, type,
11879 fold_convert (TREE_TYPE (arg1), tem), arg1);
11883 /* If this is an NE or EQ comparison of zero against the result of a
11884 signed MOD operation whose second operand is a power of 2, make
11885 the MOD operation unsigned since it is simpler and equivalent. */
11886 if (integer_zerop (arg1)
11887 && !TYPE_UNSIGNED (TREE_TYPE (arg0))
11888 && (TREE_CODE (arg0) == TRUNC_MOD_EXPR
11889 || TREE_CODE (arg0) == CEIL_MOD_EXPR
11890 || TREE_CODE (arg0) == FLOOR_MOD_EXPR
11891 || TREE_CODE (arg0) == ROUND_MOD_EXPR)
11892 && integer_pow2p (TREE_OPERAND (arg0, 1)))
11894 tree newtype = unsigned_type_for (TREE_TYPE (arg0));
11895 tree newmod = fold_build2 (TREE_CODE (arg0), newtype,
11896 fold_convert (newtype,
11897 TREE_OPERAND (arg0, 0)),
11898 fold_convert (newtype,
11899 TREE_OPERAND (arg0, 1)));
11901 return fold_build2 (code, type, newmod,
11902 fold_convert (newtype, arg1));
11905 /* Fold ((X >> C1) & C2) == 0 and ((X >> C1) & C2) != 0 where
11906 C1 is a valid shift constant, and C2 is a power of two, i.e.
11908 if (TREE_CODE (arg0) == BIT_AND_EXPR
11909 && TREE_CODE (TREE_OPERAND (arg0, 0)) == RSHIFT_EXPR
11910 && TREE_CODE (TREE_OPERAND (TREE_OPERAND (arg0, 0), 1))
11912 && integer_pow2p (TREE_OPERAND (arg0, 1))
11913 && integer_zerop (arg1))
11915 tree itype = TREE_TYPE (arg0);
11916 unsigned HOST_WIDE_INT prec = TYPE_PRECISION (itype);
11917 tree arg001 = TREE_OPERAND (TREE_OPERAND (arg0, 0), 1);
11919 /* Check for a valid shift count. */
11920 if (TREE_INT_CST_HIGH (arg001) == 0
11921 && TREE_INT_CST_LOW (arg001) < prec)
11923 tree arg01 = TREE_OPERAND (arg0, 1);
11924 tree arg000 = TREE_OPERAND (TREE_OPERAND (arg0, 0), 0);
11925 unsigned HOST_WIDE_INT log2 = tree_log2 (arg01);
11926 /* If (C2 << C1) doesn't overflow, then ((X >> C1) & C2) != 0
11927 can be rewritten as (X & (C2 << C1)) != 0. */
11928 if ((log2 + TREE_INT_CST_LOW (arg001)) < prec)
11930 tem = fold_build2 (LSHIFT_EXPR, itype, arg01, arg001);
11931 tem = fold_build2 (BIT_AND_EXPR, itype, arg000, tem);
11932 return fold_build2 (code, type, tem, arg1);
11934 /* Otherwise, for signed (arithmetic) shifts,
11935 ((X >> C1) & C2) != 0 is rewritten as X < 0, and
11936 ((X >> C1) & C2) == 0 is rewritten as X >= 0. */
11937 else if (!TYPE_UNSIGNED (itype))
11938 return fold_build2 (code == EQ_EXPR ? GE_EXPR : LT_EXPR, type,
11939 arg000, build_int_cst (itype, 0));
11940 /* Otherwise, of unsigned (logical) shifts,
11941 ((X >> C1) & C2) != 0 is rewritten as (X,false), and
11942 ((X >> C1) & C2) == 0 is rewritten as (X,true). */
11944 return omit_one_operand (type,
11945 code == EQ_EXPR ? integer_one_node
11946 : integer_zero_node,
11951 /* If this is an NE comparison of zero with an AND of one, remove the
11952 comparison since the AND will give the correct value. */
11953 if (code == NE_EXPR
11954 && integer_zerop (arg1)
11955 && TREE_CODE (arg0) == BIT_AND_EXPR
11956 && integer_onep (TREE_OPERAND (arg0, 1)))
11957 return fold_convert (type, arg0);
11959 /* If we have (A & C) == C where C is a power of 2, convert this into
11960 (A & C) != 0. Similarly for NE_EXPR. */
11961 if (TREE_CODE (arg0) == BIT_AND_EXPR
11962 && integer_pow2p (TREE_OPERAND (arg0, 1))
11963 && operand_equal_p (TREE_OPERAND (arg0, 1), arg1, 0))
11964 return fold_build2 (code == EQ_EXPR ? NE_EXPR : EQ_EXPR, type,
11965 arg0, fold_convert (TREE_TYPE (arg0),
11966 integer_zero_node));
11968 /* If we have (A & C) != 0 or (A & C) == 0 and C is the sign
11969 bit, then fold the expression into A < 0 or A >= 0. */
11970 tem = fold_single_bit_test_into_sign_test (code, arg0, arg1, type);
11974 /* If we have (A & C) == D where D & ~C != 0, convert this into 0.
11975 Similarly for NE_EXPR. */
11976 if (TREE_CODE (arg0) == BIT_AND_EXPR
11977 && TREE_CODE (arg1) == INTEGER_CST
11978 && TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST)
11980 tree notc = fold_build1 (BIT_NOT_EXPR,
11981 TREE_TYPE (TREE_OPERAND (arg0, 1)),
11982 TREE_OPERAND (arg0, 1));
11983 tree dandnotc = fold_build2 (BIT_AND_EXPR, TREE_TYPE (arg0),
11985 tree rslt = code == EQ_EXPR ? integer_zero_node : integer_one_node;
11986 if (integer_nonzerop (dandnotc))
11987 return omit_one_operand (type, rslt, arg0);
11990 /* If we have (A | C) == D where C & ~D != 0, convert this into 0.
11991 Similarly for NE_EXPR. */
11992 if (TREE_CODE (arg0) == BIT_IOR_EXPR
11993 && TREE_CODE (arg1) == INTEGER_CST
11994 && TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST)
11996 tree notd = fold_build1 (BIT_NOT_EXPR, TREE_TYPE (arg1), arg1);
11997 tree candnotd = fold_build2 (BIT_AND_EXPR, TREE_TYPE (arg0),
11998 TREE_OPERAND (arg0, 1), notd);
11999 tree rslt = code == EQ_EXPR ? integer_zero_node : integer_one_node;
12000 if (integer_nonzerop (candnotd))
12001 return omit_one_operand (type, rslt, arg0);
12004 /* Optimize comparisons of strlen vs zero to a compare of the
12005 first character of the string vs zero. To wit,
12006 strlen(ptr) == 0 => *ptr == 0
12007 strlen(ptr) != 0 => *ptr != 0
12008 Other cases should reduce to one of these two (or a constant)
12009 due to the return value of strlen being unsigned. */
12010 if (TREE_CODE (arg0) == CALL_EXPR
12011 && integer_zerop (arg1))
12013 tree fndecl = get_callee_fndecl (arg0);
12016 && DECL_BUILT_IN_CLASS (fndecl) == BUILT_IN_NORMAL
12017 && DECL_FUNCTION_CODE (fndecl) == BUILT_IN_STRLEN
12018 && call_expr_nargs (arg0) == 1
12019 && TREE_CODE (TREE_TYPE (CALL_EXPR_ARG (arg0, 0))) == POINTER_TYPE)
12021 tree iref = build_fold_indirect_ref (CALL_EXPR_ARG (arg0, 0));
12022 return fold_build2 (code, type, iref,
12023 build_int_cst (TREE_TYPE (iref), 0));
12027 /* Fold (X >> C) != 0 into X < 0 if C is one less than the width
12028 of X. Similarly fold (X >> C) == 0 into X >= 0. */
12029 if (TREE_CODE (arg0) == RSHIFT_EXPR
12030 && integer_zerop (arg1)
12031 && TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST)
12033 tree arg00 = TREE_OPERAND (arg0, 0);
12034 tree arg01 = TREE_OPERAND (arg0, 1);
12035 tree itype = TREE_TYPE (arg00);
12036 if (TREE_INT_CST_HIGH (arg01) == 0
12037 && TREE_INT_CST_LOW (arg01)
12038 == (unsigned HOST_WIDE_INT) (TYPE_PRECISION (itype) - 1))
12040 if (TYPE_UNSIGNED (itype))
12042 itype = signed_type_for (itype);
12043 arg00 = fold_convert (itype, arg00);
12045 return fold_build2 (code == EQ_EXPR ? GE_EXPR : LT_EXPR,
12046 type, arg00, build_int_cst (itype, 0));
12050 /* (X ^ Y) == 0 becomes X == Y, and (X ^ Y) != 0 becomes X != Y. */
12051 if (integer_zerop (arg1)
12052 && TREE_CODE (arg0) == BIT_XOR_EXPR)
12053 return fold_build2 (code, type, TREE_OPERAND (arg0, 0),
12054 TREE_OPERAND (arg0, 1));
12056 /* (X ^ Y) == Y becomes X == 0. We know that Y has no side-effects. */
12057 if (TREE_CODE (arg0) == BIT_XOR_EXPR
12058 && operand_equal_p (TREE_OPERAND (arg0, 1), arg1, 0))
12059 return fold_build2 (code, type, TREE_OPERAND (arg0, 0),
12060 build_int_cst (TREE_TYPE (arg1), 0));
12061 /* Likewise (X ^ Y) == X becomes Y == 0. X has no side-effects. */
12062 if (TREE_CODE (arg0) == BIT_XOR_EXPR
12063 && operand_equal_p (TREE_OPERAND (arg0, 0), arg1, 0)
12064 && reorder_operands_p (TREE_OPERAND (arg0, 1), arg1))
12065 return fold_build2 (code, type, TREE_OPERAND (arg0, 1),
12066 build_int_cst (TREE_TYPE (arg1), 0));
12068 /* (X ^ C1) op C2 can be rewritten as X op (C1 ^ C2). */
12069 if (TREE_CODE (arg0) == BIT_XOR_EXPR
12070 && TREE_CODE (arg1) == INTEGER_CST
12071 && TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST)
12072 return fold_build2 (code, type, TREE_OPERAND (arg0, 0),
12073 fold_build2 (BIT_XOR_EXPR, TREE_TYPE (arg1),
12074 TREE_OPERAND (arg0, 1), arg1));
12076 /* Fold (~X & C) == 0 into (X & C) != 0 and (~X & C) != 0 into
12077 (X & C) == 0 when C is a single bit. */
12078 if (TREE_CODE (arg0) == BIT_AND_EXPR
12079 && TREE_CODE (TREE_OPERAND (arg0, 0)) == BIT_NOT_EXPR
12080 && integer_zerop (arg1)
12081 && integer_pow2p (TREE_OPERAND (arg0, 1)))
12083 tem = fold_build2 (BIT_AND_EXPR, TREE_TYPE (arg0),
12084 TREE_OPERAND (TREE_OPERAND (arg0, 0), 0),
12085 TREE_OPERAND (arg0, 1));
12086 return fold_build2 (code == EQ_EXPR ? NE_EXPR : EQ_EXPR,
12090 /* Fold ((X & C) ^ C) eq/ne 0 into (X & C) ne/eq 0, when the
12091 constant C is a power of two, i.e. a single bit. */
12092 if (TREE_CODE (arg0) == BIT_XOR_EXPR
12093 && TREE_CODE (TREE_OPERAND (arg0, 0)) == BIT_AND_EXPR
12094 && integer_zerop (arg1)
12095 && integer_pow2p (TREE_OPERAND (arg0, 1))
12096 && operand_equal_p (TREE_OPERAND (TREE_OPERAND (arg0, 0), 1),
12097 TREE_OPERAND (arg0, 1), OEP_ONLY_CONST))
12099 tree arg00 = TREE_OPERAND (arg0, 0);
12100 return fold_build2 (code == EQ_EXPR ? NE_EXPR : EQ_EXPR, type,
12101 arg00, build_int_cst (TREE_TYPE (arg00), 0));
12104 /* Likewise, fold ((X ^ C) & C) eq/ne 0 into (X & C) ne/eq 0,
12105 when is C is a power of two, i.e. a single bit. */
12106 if (TREE_CODE (arg0) == BIT_AND_EXPR
12107 && TREE_CODE (TREE_OPERAND (arg0, 0)) == BIT_XOR_EXPR
12108 && integer_zerop (arg1)
12109 && integer_pow2p (TREE_OPERAND (arg0, 1))
12110 && operand_equal_p (TREE_OPERAND (TREE_OPERAND (arg0, 0), 1),
12111 TREE_OPERAND (arg0, 1), OEP_ONLY_CONST))
12113 tree arg000 = TREE_OPERAND (TREE_OPERAND (arg0, 0), 0);
12114 tem = fold_build2 (BIT_AND_EXPR, TREE_TYPE (arg000),
12115 arg000, TREE_OPERAND (arg0, 1));
12116 return fold_build2 (code == EQ_EXPR ? NE_EXPR : EQ_EXPR, type,
12117 tem, build_int_cst (TREE_TYPE (tem), 0));
12120 if (integer_zerop (arg1)
12121 && tree_expr_nonzero_p (arg0))
12123 tree res = constant_boolean_node (code==NE_EXPR, type);
12124 return omit_one_operand (type, res, arg0);
12127 /* Fold -X op -Y as X op Y, where op is eq/ne. */
12128 if (TREE_CODE (arg0) == NEGATE_EXPR
12129 && TREE_CODE (arg1) == NEGATE_EXPR)
12130 return fold_build2 (code, type,
12131 TREE_OPERAND (arg0, 0),
12132 TREE_OPERAND (arg1, 0));
12134 /* Fold (X & C) op (Y & C) as (X ^ Y) & C op 0", and symmetries. */
12135 if (TREE_CODE (arg0) == BIT_AND_EXPR
12136 && TREE_CODE (arg1) == BIT_AND_EXPR)
12138 tree arg00 = TREE_OPERAND (arg0, 0);
12139 tree arg01 = TREE_OPERAND (arg0, 1);
12140 tree arg10 = TREE_OPERAND (arg1, 0);
12141 tree arg11 = TREE_OPERAND (arg1, 1);
12142 tree itype = TREE_TYPE (arg0);
12144 if (operand_equal_p (arg01, arg11, 0))
12145 return fold_build2 (code, type,
12146 fold_build2 (BIT_AND_EXPR, itype,
12147 fold_build2 (BIT_XOR_EXPR, itype,
12150 build_int_cst (itype, 0));
12152 if (operand_equal_p (arg01, arg10, 0))
12153 return fold_build2 (code, type,
12154 fold_build2 (BIT_AND_EXPR, itype,
12155 fold_build2 (BIT_XOR_EXPR, itype,
12158 build_int_cst (itype, 0));
12160 if (operand_equal_p (arg00, arg11, 0))
12161 return fold_build2 (code, type,
12162 fold_build2 (BIT_AND_EXPR, itype,
12163 fold_build2 (BIT_XOR_EXPR, itype,
12166 build_int_cst (itype, 0));
12168 if (operand_equal_p (arg00, arg10, 0))
12169 return fold_build2 (code, type,
12170 fold_build2 (BIT_AND_EXPR, itype,
12171 fold_build2 (BIT_XOR_EXPR, itype,
12174 build_int_cst (itype, 0));
12177 if (TREE_CODE (arg0) == BIT_XOR_EXPR
12178 && TREE_CODE (arg1) == BIT_XOR_EXPR)
12180 tree arg00 = TREE_OPERAND (arg0, 0);
12181 tree arg01 = TREE_OPERAND (arg0, 1);
12182 tree arg10 = TREE_OPERAND (arg1, 0);
12183 tree arg11 = TREE_OPERAND (arg1, 1);
12184 tree itype = TREE_TYPE (arg0);
12186 /* Optimize (X ^ Z) op (Y ^ Z) as X op Y, and symmetries.
12187 operand_equal_p guarantees no side-effects so we don't need
12188 to use omit_one_operand on Z. */
12189 if (operand_equal_p (arg01, arg11, 0))
12190 return fold_build2 (code, type, arg00, arg10);
12191 if (operand_equal_p (arg01, arg10, 0))
12192 return fold_build2 (code, type, arg00, arg11);
12193 if (operand_equal_p (arg00, arg11, 0))
12194 return fold_build2 (code, type, arg01, arg10);
12195 if (operand_equal_p (arg00, arg10, 0))
12196 return fold_build2 (code, type, arg01, arg11);
12198 /* Optimize (X ^ C1) op (Y ^ C2) as (X ^ (C1 ^ C2)) op Y. */
12199 if (TREE_CODE (arg01) == INTEGER_CST
12200 && TREE_CODE (arg11) == INTEGER_CST)
12201 return fold_build2 (code, type,
12202 fold_build2 (BIT_XOR_EXPR, itype, arg00,
12203 fold_build2 (BIT_XOR_EXPR, itype,
12208 /* Attempt to simplify equality/inequality comparisons of complex
12209 values. Only lower the comparison if the result is known or
12210 can be simplified to a single scalar comparison. */
12211 if ((TREE_CODE (arg0) == COMPLEX_EXPR
12212 || TREE_CODE (arg0) == COMPLEX_CST)
12213 && (TREE_CODE (arg1) == COMPLEX_EXPR
12214 || TREE_CODE (arg1) == COMPLEX_CST))
12216 tree real0, imag0, real1, imag1;
12219 if (TREE_CODE (arg0) == COMPLEX_EXPR)
12221 real0 = TREE_OPERAND (arg0, 0);
12222 imag0 = TREE_OPERAND (arg0, 1);
12226 real0 = TREE_REALPART (arg0);
12227 imag0 = TREE_IMAGPART (arg0);
12230 if (TREE_CODE (arg1) == COMPLEX_EXPR)
12232 real1 = TREE_OPERAND (arg1, 0);
12233 imag1 = TREE_OPERAND (arg1, 1);
12237 real1 = TREE_REALPART (arg1);
12238 imag1 = TREE_IMAGPART (arg1);
12241 rcond = fold_binary (code, type, real0, real1);
12242 if (rcond && TREE_CODE (rcond) == INTEGER_CST)
12244 if (integer_zerop (rcond))
12246 if (code == EQ_EXPR)
12247 return omit_two_operands (type, boolean_false_node,
12249 return fold_build2 (NE_EXPR, type, imag0, imag1);
12253 if (code == NE_EXPR)
12254 return omit_two_operands (type, boolean_true_node,
12256 return fold_build2 (EQ_EXPR, type, imag0, imag1);
12260 icond = fold_binary (code, type, imag0, imag1);
12261 if (icond && TREE_CODE (icond) == INTEGER_CST)
12263 if (integer_zerop (icond))
12265 if (code == EQ_EXPR)
12266 return omit_two_operands (type, boolean_false_node,
12268 return fold_build2 (NE_EXPR, type, real0, real1);
12272 if (code == NE_EXPR)
12273 return omit_two_operands (type, boolean_true_node,
12275 return fold_build2 (EQ_EXPR, type, real0, real1);
12286 tem = fold_comparison (code, type, op0, op1);
12287 if (tem != NULL_TREE)
12290 /* Transform comparisons of the form X +- C CMP X. */
12291 if ((TREE_CODE (arg0) == PLUS_EXPR || TREE_CODE (arg0) == MINUS_EXPR)
12292 && operand_equal_p (TREE_OPERAND (arg0, 0), arg1, 0)
12293 && ((TREE_CODE (TREE_OPERAND (arg0, 1)) == REAL_CST
12294 && !HONOR_SNANS (TYPE_MODE (TREE_TYPE (arg0))))
12295 || (TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST
12296 && TYPE_OVERFLOW_UNDEFINED (TREE_TYPE (arg1)))))
12298 tree arg01 = TREE_OPERAND (arg0, 1);
12299 enum tree_code code0 = TREE_CODE (arg0);
12302 if (TREE_CODE (arg01) == REAL_CST)
12303 is_positive = REAL_VALUE_NEGATIVE (TREE_REAL_CST (arg01)) ? -1 : 1;
12305 is_positive = tree_int_cst_sgn (arg01);
12307 /* (X - c) > X becomes false. */
12308 if (code == GT_EXPR
12309 && ((code0 == MINUS_EXPR && is_positive >= 0)
12310 || (code0 == PLUS_EXPR && is_positive <= 0)))
12312 if (TREE_CODE (arg01) == INTEGER_CST
12313 && TYPE_OVERFLOW_UNDEFINED (TREE_TYPE (arg1)))
12314 fold_overflow_warning (("assuming signed overflow does not "
12315 "occur when assuming that (X - c) > X "
12316 "is always false"),
12317 WARN_STRICT_OVERFLOW_ALL);
12318 return constant_boolean_node (0, type);
12321 /* Likewise (X + c) < X becomes false. */
12322 if (code == LT_EXPR
12323 && ((code0 == PLUS_EXPR && is_positive >= 0)
12324 || (code0 == MINUS_EXPR && is_positive <= 0)))
12326 if (TREE_CODE (arg01) == INTEGER_CST
12327 && TYPE_OVERFLOW_UNDEFINED (TREE_TYPE (arg1)))
12328 fold_overflow_warning (("assuming signed overflow does not "
12329 "occur when assuming that "
12330 "(X + c) < X is always false"),
12331 WARN_STRICT_OVERFLOW_ALL);
12332 return constant_boolean_node (0, type);
12335 /* Convert (X - c) <= X to true. */
12336 if (!HONOR_NANS (TYPE_MODE (TREE_TYPE (arg1)))
12338 && ((code0 == MINUS_EXPR && is_positive >= 0)
12339 || (code0 == PLUS_EXPR && is_positive <= 0)))
12341 if (TREE_CODE (arg01) == INTEGER_CST
12342 && TYPE_OVERFLOW_UNDEFINED (TREE_TYPE (arg1)))
12343 fold_overflow_warning (("assuming signed overflow does not "
12344 "occur when assuming that "
12345 "(X - c) <= X is always true"),
12346 WARN_STRICT_OVERFLOW_ALL);
12347 return constant_boolean_node (1, type);
12350 /* Convert (X + c) >= X to true. */
12351 if (!HONOR_NANS (TYPE_MODE (TREE_TYPE (arg1)))
12353 && ((code0 == PLUS_EXPR && is_positive >= 0)
12354 || (code0 == MINUS_EXPR && is_positive <= 0)))
12356 if (TREE_CODE (arg01) == INTEGER_CST
12357 && TYPE_OVERFLOW_UNDEFINED (TREE_TYPE (arg1)))
12358 fold_overflow_warning (("assuming signed overflow does not "
12359 "occur when assuming that "
12360 "(X + c) >= X is always true"),
12361 WARN_STRICT_OVERFLOW_ALL);
12362 return constant_boolean_node (1, type);
12365 if (TREE_CODE (arg01) == INTEGER_CST)
12367 /* Convert X + c > X and X - c < X to true for integers. */
12368 if (code == GT_EXPR
12369 && ((code0 == PLUS_EXPR && is_positive > 0)
12370 || (code0 == MINUS_EXPR && is_positive < 0)))
12372 if (TYPE_OVERFLOW_UNDEFINED (TREE_TYPE (arg1)))
12373 fold_overflow_warning (("assuming signed overflow does "
12374 "not occur when assuming that "
12375 "(X + c) > X is always true"),
12376 WARN_STRICT_OVERFLOW_ALL);
12377 return constant_boolean_node (1, type);
12380 if (code == LT_EXPR
12381 && ((code0 == MINUS_EXPR && is_positive > 0)
12382 || (code0 == PLUS_EXPR && is_positive < 0)))
12384 if (TYPE_OVERFLOW_UNDEFINED (TREE_TYPE (arg1)))
12385 fold_overflow_warning (("assuming signed overflow does "
12386 "not occur when assuming that "
12387 "(X - c) < X is always true"),
12388 WARN_STRICT_OVERFLOW_ALL);
12389 return constant_boolean_node (1, type);
12392 /* Convert X + c <= X and X - c >= X to false for integers. */
12393 if (code == LE_EXPR
12394 && ((code0 == PLUS_EXPR && is_positive > 0)
12395 || (code0 == MINUS_EXPR && is_positive < 0)))
12397 if (TYPE_OVERFLOW_UNDEFINED (TREE_TYPE (arg1)))
12398 fold_overflow_warning (("assuming signed overflow does "
12399 "not occur when assuming that "
12400 "(X + c) <= X is always false"),
12401 WARN_STRICT_OVERFLOW_ALL);
12402 return constant_boolean_node (0, type);
12405 if (code == GE_EXPR
12406 && ((code0 == MINUS_EXPR && is_positive > 0)
12407 || (code0 == PLUS_EXPR && is_positive < 0)))
12409 if (TYPE_OVERFLOW_UNDEFINED (TREE_TYPE (arg1)))
12410 fold_overflow_warning (("assuming signed overflow does "
12411 "not occur when assuming that "
12412 "(X - c) >= X is always false"),
12413 WARN_STRICT_OVERFLOW_ALL);
12414 return constant_boolean_node (0, type);
12419 /* Change X >= C to X > (C - 1) and X < C to X <= (C - 1) if C > 0.
12420 This transformation affects the cases which are handled in later
12421 optimizations involving comparisons with non-negative constants. */
12422 if (TREE_CODE (arg1) == INTEGER_CST
12423 && TREE_CODE (arg0) != INTEGER_CST
12424 && tree_int_cst_sgn (arg1) > 0)
12426 if (code == GE_EXPR)
12428 arg1 = const_binop (MINUS_EXPR, arg1,
12429 build_int_cst (TREE_TYPE (arg1), 1), 0);
12430 return fold_build2 (GT_EXPR, type, arg0,
12431 fold_convert (TREE_TYPE (arg0), arg1));
12433 if (code == LT_EXPR)
12435 arg1 = const_binop (MINUS_EXPR, arg1,
12436 build_int_cst (TREE_TYPE (arg1), 1), 0);
12437 return fold_build2 (LE_EXPR, type, arg0,
12438 fold_convert (TREE_TYPE (arg0), arg1));
12442 /* Comparisons with the highest or lowest possible integer of
12443 the specified precision will have known values. */
12445 tree arg1_type = TREE_TYPE (arg1);
12446 unsigned int width = TYPE_PRECISION (arg1_type);
12448 if (TREE_CODE (arg1) == INTEGER_CST
12449 && !TREE_OVERFLOW (arg1)
12450 && width <= 2 * HOST_BITS_PER_WIDE_INT
12451 && (INTEGRAL_TYPE_P (arg1_type) || POINTER_TYPE_P (arg1_type)))
12453 HOST_WIDE_INT signed_max_hi;
12454 unsigned HOST_WIDE_INT signed_max_lo;
12455 unsigned HOST_WIDE_INT max_hi, max_lo, min_hi, min_lo;
12457 if (width <= HOST_BITS_PER_WIDE_INT)
12459 signed_max_lo = ((unsigned HOST_WIDE_INT) 1 << (width - 1))
12464 if (TYPE_UNSIGNED (arg1_type))
12466 max_lo = ((unsigned HOST_WIDE_INT) 2 << (width - 1)) - 1;
12472 max_lo = signed_max_lo;
12473 min_lo = ((unsigned HOST_WIDE_INT) -1 << (width - 1));
12479 width -= HOST_BITS_PER_WIDE_INT;
12480 signed_max_lo = -1;
12481 signed_max_hi = ((unsigned HOST_WIDE_INT) 1 << (width - 1))
12486 if (TYPE_UNSIGNED (arg1_type))
12488 max_hi = ((unsigned HOST_WIDE_INT) 2 << (width - 1)) - 1;
12493 max_hi = signed_max_hi;
12494 min_hi = ((unsigned HOST_WIDE_INT) -1 << (width - 1));
12498 if ((unsigned HOST_WIDE_INT) TREE_INT_CST_HIGH (arg1) == max_hi
12499 && TREE_INT_CST_LOW (arg1) == max_lo)
12503 return omit_one_operand (type, integer_zero_node, arg0);
12506 return fold_build2 (EQ_EXPR, type, op0, op1);
12509 return omit_one_operand (type, integer_one_node, arg0);
12512 return fold_build2 (NE_EXPR, type, op0, op1);
12514 /* The GE_EXPR and LT_EXPR cases above are not normally
12515 reached because of previous transformations. */
12520 else if ((unsigned HOST_WIDE_INT) TREE_INT_CST_HIGH (arg1)
12522 && TREE_INT_CST_LOW (arg1) == max_lo - 1)
12526 arg1 = const_binop (PLUS_EXPR, arg1,
12527 build_int_cst (TREE_TYPE (arg1), 1), 0);
12528 return fold_build2 (EQ_EXPR, type,
12529 fold_convert (TREE_TYPE (arg1), arg0),
12532 arg1 = const_binop (PLUS_EXPR, arg1,
12533 build_int_cst (TREE_TYPE (arg1), 1), 0);
12534 return fold_build2 (NE_EXPR, type,
12535 fold_convert (TREE_TYPE (arg1), arg0),
12540 else if ((unsigned HOST_WIDE_INT) TREE_INT_CST_HIGH (arg1)
12542 && TREE_INT_CST_LOW (arg1) == min_lo)
12546 return omit_one_operand (type, integer_zero_node, arg0);
12549 return fold_build2 (EQ_EXPR, type, op0, op1);
12552 return omit_one_operand (type, integer_one_node, arg0);
12555 return fold_build2 (NE_EXPR, type, op0, op1);
12560 else if ((unsigned HOST_WIDE_INT) TREE_INT_CST_HIGH (arg1)
12562 && TREE_INT_CST_LOW (arg1) == min_lo + 1)
12566 arg1 = const_binop (MINUS_EXPR, arg1, integer_one_node, 0);
12567 return fold_build2 (NE_EXPR, type,
12568 fold_convert (TREE_TYPE (arg1), arg0),
12571 arg1 = const_binop (MINUS_EXPR, arg1, integer_one_node, 0);
12572 return fold_build2 (EQ_EXPR, type,
12573 fold_convert (TREE_TYPE (arg1), arg0),
12579 else if (TREE_INT_CST_HIGH (arg1) == signed_max_hi
12580 && TREE_INT_CST_LOW (arg1) == signed_max_lo
12581 && TYPE_UNSIGNED (arg1_type)
12582 /* We will flip the signedness of the comparison operator
12583 associated with the mode of arg1, so the sign bit is
12584 specified by this mode. Check that arg1 is the signed
12585 max associated with this sign bit. */
12586 && width == GET_MODE_BITSIZE (TYPE_MODE (arg1_type))
12587 /* signed_type does not work on pointer types. */
12588 && INTEGRAL_TYPE_P (arg1_type))
12590 /* The following case also applies to X < signed_max+1
12591 and X >= signed_max+1 because previous transformations. */
12592 if (code == LE_EXPR || code == GT_EXPR)
12595 st = signed_type_for (TREE_TYPE (arg1));
12596 return fold_build2 (code == LE_EXPR ? GE_EXPR : LT_EXPR,
12597 type, fold_convert (st, arg0),
12598 build_int_cst (st, 0));
12604 /* If we are comparing an ABS_EXPR with a constant, we can
12605 convert all the cases into explicit comparisons, but they may
12606 well not be faster than doing the ABS and one comparison.
12607 But ABS (X) <= C is a range comparison, which becomes a subtraction
12608 and a comparison, and is probably faster. */
12609 if (code == LE_EXPR
12610 && TREE_CODE (arg1) == INTEGER_CST
12611 && TREE_CODE (arg0) == ABS_EXPR
12612 && ! TREE_SIDE_EFFECTS (arg0)
12613 && (0 != (tem = negate_expr (arg1)))
12614 && TREE_CODE (tem) == INTEGER_CST
12615 && !TREE_OVERFLOW (tem))
12616 return fold_build2 (TRUTH_ANDIF_EXPR, type,
12617 build2 (GE_EXPR, type,
12618 TREE_OPERAND (arg0, 0), tem),
12619 build2 (LE_EXPR, type,
12620 TREE_OPERAND (arg0, 0), arg1));
12622 /* Convert ABS_EXPR<x> >= 0 to true. */
12623 strict_overflow_p = false;
12624 if (code == GE_EXPR
12625 && (integer_zerop (arg1)
12626 || (! HONOR_NANS (TYPE_MODE (TREE_TYPE (arg0)))
12627 && real_zerop (arg1)))
12628 && tree_expr_nonnegative_warnv_p (arg0, &strict_overflow_p))
12630 if (strict_overflow_p)
12631 fold_overflow_warning (("assuming signed overflow does not occur "
12632 "when simplifying comparison of "
12633 "absolute value and zero"),
12634 WARN_STRICT_OVERFLOW_CONDITIONAL);
12635 return omit_one_operand (type, integer_one_node, arg0);
12638 /* Convert ABS_EXPR<x> < 0 to false. */
12639 strict_overflow_p = false;
12640 if (code == LT_EXPR
12641 && (integer_zerop (arg1) || real_zerop (arg1))
12642 && tree_expr_nonnegative_warnv_p (arg0, &strict_overflow_p))
12644 if (strict_overflow_p)
12645 fold_overflow_warning (("assuming signed overflow does not occur "
12646 "when simplifying comparison of "
12647 "absolute value and zero"),
12648 WARN_STRICT_OVERFLOW_CONDITIONAL);
12649 return omit_one_operand (type, integer_zero_node, arg0);
12652 /* If X is unsigned, convert X < (1 << Y) into X >> Y == 0
12653 and similarly for >= into !=. */
12654 if ((code == LT_EXPR || code == GE_EXPR)
12655 && TYPE_UNSIGNED (TREE_TYPE (arg0))
12656 && TREE_CODE (arg1) == LSHIFT_EXPR
12657 && integer_onep (TREE_OPERAND (arg1, 0)))
12658 return build2 (code == LT_EXPR ? EQ_EXPR : NE_EXPR, type,
12659 build2 (RSHIFT_EXPR, TREE_TYPE (arg0), arg0,
12660 TREE_OPERAND (arg1, 1)),
12661 build_int_cst (TREE_TYPE (arg0), 0));
12663 if ((code == LT_EXPR || code == GE_EXPR)
12664 && TYPE_UNSIGNED (TREE_TYPE (arg0))
12665 && (TREE_CODE (arg1) == NOP_EXPR
12666 || TREE_CODE (arg1) == CONVERT_EXPR)
12667 && TREE_CODE (TREE_OPERAND (arg1, 0)) == LSHIFT_EXPR
12668 && integer_onep (TREE_OPERAND (TREE_OPERAND (arg1, 0), 0)))
12670 build2 (code == LT_EXPR ? EQ_EXPR : NE_EXPR, type,
12671 fold_convert (TREE_TYPE (arg0),
12672 build2 (RSHIFT_EXPR, TREE_TYPE (arg0), arg0,
12673 TREE_OPERAND (TREE_OPERAND (arg1, 0),
12675 build_int_cst (TREE_TYPE (arg0), 0));
12679 case UNORDERED_EXPR:
12687 if (TREE_CODE (arg0) == REAL_CST && TREE_CODE (arg1) == REAL_CST)
12689 t1 = fold_relational_const (code, type, arg0, arg1);
12690 if (t1 != NULL_TREE)
12694 /* If the first operand is NaN, the result is constant. */
12695 if (TREE_CODE (arg0) == REAL_CST
12696 && REAL_VALUE_ISNAN (TREE_REAL_CST (arg0))
12697 && (code != LTGT_EXPR || ! flag_trapping_math))
12699 t1 = (code == ORDERED_EXPR || code == LTGT_EXPR)
12700 ? integer_zero_node
12701 : integer_one_node;
12702 return omit_one_operand (type, t1, arg1);
12705 /* If the second operand is NaN, the result is constant. */
12706 if (TREE_CODE (arg1) == REAL_CST
12707 && REAL_VALUE_ISNAN (TREE_REAL_CST (arg1))
12708 && (code != LTGT_EXPR || ! flag_trapping_math))
12710 t1 = (code == ORDERED_EXPR || code == LTGT_EXPR)
12711 ? integer_zero_node
12712 : integer_one_node;
12713 return omit_one_operand (type, t1, arg0);
12716 /* Simplify unordered comparison of something with itself. */
12717 if ((code == UNLE_EXPR || code == UNGE_EXPR || code == UNEQ_EXPR)
12718 && operand_equal_p (arg0, arg1, 0))
12719 return constant_boolean_node (1, type);
12721 if (code == LTGT_EXPR
12722 && !flag_trapping_math
12723 && operand_equal_p (arg0, arg1, 0))
12724 return constant_boolean_node (0, type);
12726 /* Fold (double)float1 CMP (double)float2 into float1 CMP float2. */
12728 tree targ0 = strip_float_extensions (arg0);
12729 tree targ1 = strip_float_extensions (arg1);
12730 tree newtype = TREE_TYPE (targ0);
12732 if (TYPE_PRECISION (TREE_TYPE (targ1)) > TYPE_PRECISION (newtype))
12733 newtype = TREE_TYPE (targ1);
12735 if (TYPE_PRECISION (newtype) < TYPE_PRECISION (TREE_TYPE (arg0)))
12736 return fold_build2 (code, type, fold_convert (newtype, targ0),
12737 fold_convert (newtype, targ1));
12742 case COMPOUND_EXPR:
12743 /* When pedantic, a compound expression can be neither an lvalue
12744 nor an integer constant expression. */
12745 if (TREE_SIDE_EFFECTS (arg0) || TREE_CONSTANT (arg1))
12747 /* Don't let (0, 0) be null pointer constant. */
12748 tem = integer_zerop (arg1) ? build1 (NOP_EXPR, type, arg1)
12749 : fold_convert (type, arg1);
12750 return pedantic_non_lvalue (tem);
12753 if ((TREE_CODE (arg0) == REAL_CST
12754 && TREE_CODE (arg1) == REAL_CST)
12755 || (TREE_CODE (arg0) == INTEGER_CST
12756 && TREE_CODE (arg1) == INTEGER_CST))
12757 return build_complex (type, arg0, arg1);
12761 /* An ASSERT_EXPR should never be passed to fold_binary. */
12762 gcc_unreachable ();
12766 } /* switch (code) */
12769 /* Callback for walk_tree, looking for LABEL_EXPR.
12770 Returns tree TP if it is LABEL_EXPR. Otherwise it returns NULL_TREE.
12771 Do not check the sub-tree of GOTO_EXPR. */
12774 contains_label_1 (tree *tp,
12775 int *walk_subtrees,
12776 void *data ATTRIBUTE_UNUSED)
12778 switch (TREE_CODE (*tp))
12783 *walk_subtrees = 0;
12790 /* Checks whether the sub-tree ST contains a label LABEL_EXPR which is
12791 accessible from outside the sub-tree. Returns NULL_TREE if no
12792 addressable label is found. */
12795 contains_label_p (tree st)
12797 return (walk_tree (&st, contains_label_1 , NULL, NULL) != NULL_TREE);
12800 /* Fold a ternary expression of code CODE and type TYPE with operands
12801 OP0, OP1, and OP2. Return the folded expression if folding is
12802 successful. Otherwise, return NULL_TREE. */
12805 fold_ternary (enum tree_code code, tree type, tree op0, tree op1, tree op2)
12808 tree arg0 = NULL_TREE, arg1 = NULL_TREE;
12809 enum tree_code_class kind = TREE_CODE_CLASS (code);
12811 gcc_assert (IS_EXPR_CODE_CLASS (kind)
12812 && TREE_CODE_LENGTH (code) == 3);
12814 /* Strip any conversions that don't change the mode. This is safe
12815 for every expression, except for a comparison expression because
12816 its signedness is derived from its operands. So, in the latter
12817 case, only strip conversions that don't change the signedness.
12819 Note that this is done as an internal manipulation within the
12820 constant folder, in order to find the simplest representation of
12821 the arguments so that their form can be studied. In any cases,
12822 the appropriate type conversions should be put back in the tree
12823 that will get out of the constant folder. */
12838 case COMPONENT_REF:
12839 if (TREE_CODE (arg0) == CONSTRUCTOR
12840 && ! type_contains_placeholder_p (TREE_TYPE (arg0)))
12842 unsigned HOST_WIDE_INT idx;
12844 FOR_EACH_CONSTRUCTOR_ELT (CONSTRUCTOR_ELTS (arg0), idx, field, value)
12851 /* Pedantic ANSI C says that a conditional expression is never an lvalue,
12852 so all simple results must be passed through pedantic_non_lvalue. */
12853 if (TREE_CODE (arg0) == INTEGER_CST)
12855 tree unused_op = integer_zerop (arg0) ? op1 : op2;
12856 tem = integer_zerop (arg0) ? op2 : op1;
12857 /* Only optimize constant conditions when the selected branch
12858 has the same type as the COND_EXPR. This avoids optimizing
12859 away "c ? x : throw", where the throw has a void type.
12860 Avoid throwing away that operand which contains label. */
12861 if ((!TREE_SIDE_EFFECTS (unused_op)
12862 || !contains_label_p (unused_op))
12863 && (! VOID_TYPE_P (TREE_TYPE (tem))
12864 || VOID_TYPE_P (type)))
12865 return pedantic_non_lvalue (tem);
12868 if (operand_equal_p (arg1, op2, 0))
12869 return pedantic_omit_one_operand (type, arg1, arg0);
12871 /* If we have A op B ? A : C, we may be able to convert this to a
12872 simpler expression, depending on the operation and the values
12873 of B and C. Signed zeros prevent all of these transformations,
12874 for reasons given above each one.
12876 Also try swapping the arguments and inverting the conditional. */
12877 if (COMPARISON_CLASS_P (arg0)
12878 && operand_equal_for_comparison_p (TREE_OPERAND (arg0, 0),
12879 arg1, TREE_OPERAND (arg0, 1))
12880 && !HONOR_SIGNED_ZEROS (TYPE_MODE (TREE_TYPE (arg1))))
12882 tem = fold_cond_expr_with_comparison (type, arg0, op1, op2);
12887 if (COMPARISON_CLASS_P (arg0)
12888 && operand_equal_for_comparison_p (TREE_OPERAND (arg0, 0),
12890 TREE_OPERAND (arg0, 1))
12891 && !HONOR_SIGNED_ZEROS (TYPE_MODE (TREE_TYPE (op2))))
12893 tem = fold_truth_not_expr (arg0);
12894 if (tem && COMPARISON_CLASS_P (tem))
12896 tem = fold_cond_expr_with_comparison (type, tem, op2, op1);
12902 /* If the second operand is simpler than the third, swap them
12903 since that produces better jump optimization results. */
12904 if (truth_value_p (TREE_CODE (arg0))
12905 && tree_swap_operands_p (op1, op2, false))
12907 /* See if this can be inverted. If it can't, possibly because
12908 it was a floating-point inequality comparison, don't do
12910 tem = fold_truth_not_expr (arg0);
12912 return fold_build3 (code, type, tem, op2, op1);
12915 /* Convert A ? 1 : 0 to simply A. */
12916 if (integer_onep (op1)
12917 && integer_zerop (op2)
12918 /* If we try to convert OP0 to our type, the
12919 call to fold will try to move the conversion inside
12920 a COND, which will recurse. In that case, the COND_EXPR
12921 is probably the best choice, so leave it alone. */
12922 && type == TREE_TYPE (arg0))
12923 return pedantic_non_lvalue (arg0);
12925 /* Convert A ? 0 : 1 to !A. This prefers the use of NOT_EXPR
12926 over COND_EXPR in cases such as floating point comparisons. */
12927 if (integer_zerop (op1)
12928 && integer_onep (op2)
12929 && truth_value_p (TREE_CODE (arg0)))
12930 return pedantic_non_lvalue (fold_convert (type,
12931 invert_truthvalue (arg0)));
12933 /* A < 0 ? <sign bit of A> : 0 is simply (A & <sign bit of A>). */
12934 if (TREE_CODE (arg0) == LT_EXPR
12935 && integer_zerop (TREE_OPERAND (arg0, 1))
12936 && integer_zerop (op2)
12937 && (tem = sign_bit_p (TREE_OPERAND (arg0, 0), arg1)))
12939 /* sign_bit_p only checks ARG1 bits within A's precision.
12940 If <sign bit of A> has wider type than A, bits outside
12941 of A's precision in <sign bit of A> need to be checked.
12942 If they are all 0, this optimization needs to be done
12943 in unsigned A's type, if they are all 1 in signed A's type,
12944 otherwise this can't be done. */
12945 if (TYPE_PRECISION (TREE_TYPE (tem))
12946 < TYPE_PRECISION (TREE_TYPE (arg1))
12947 && TYPE_PRECISION (TREE_TYPE (tem))
12948 < TYPE_PRECISION (type))
12950 unsigned HOST_WIDE_INT mask_lo;
12951 HOST_WIDE_INT mask_hi;
12952 int inner_width, outer_width;
12955 inner_width = TYPE_PRECISION (TREE_TYPE (tem));
12956 outer_width = TYPE_PRECISION (TREE_TYPE (arg1));
12957 if (outer_width > TYPE_PRECISION (type))
12958 outer_width = TYPE_PRECISION (type);
12960 if (outer_width > HOST_BITS_PER_WIDE_INT)
12962 mask_hi = ((unsigned HOST_WIDE_INT) -1
12963 >> (2 * HOST_BITS_PER_WIDE_INT - outer_width));
12969 mask_lo = ((unsigned HOST_WIDE_INT) -1
12970 >> (HOST_BITS_PER_WIDE_INT - outer_width));
12972 if (inner_width > HOST_BITS_PER_WIDE_INT)
12974 mask_hi &= ~((unsigned HOST_WIDE_INT) -1
12975 >> (HOST_BITS_PER_WIDE_INT - inner_width));
12979 mask_lo &= ~((unsigned HOST_WIDE_INT) -1
12980 >> (HOST_BITS_PER_WIDE_INT - inner_width));
12982 if ((TREE_INT_CST_HIGH (arg1) & mask_hi) == mask_hi
12983 && (TREE_INT_CST_LOW (arg1) & mask_lo) == mask_lo)
12985 tem_type = signed_type_for (TREE_TYPE (tem));
12986 tem = fold_convert (tem_type, tem);
12988 else if ((TREE_INT_CST_HIGH (arg1) & mask_hi) == 0
12989 && (TREE_INT_CST_LOW (arg1) & mask_lo) == 0)
12991 tem_type = unsigned_type_for (TREE_TYPE (tem));
12992 tem = fold_convert (tem_type, tem);
12999 return fold_convert (type,
13000 fold_build2 (BIT_AND_EXPR,
13001 TREE_TYPE (tem), tem,
13002 fold_convert (TREE_TYPE (tem),
13006 /* (A >> N) & 1 ? (1 << N) : 0 is simply A & (1 << N). A & 1 was
13007 already handled above. */
13008 if (TREE_CODE (arg0) == BIT_AND_EXPR
13009 && integer_onep (TREE_OPERAND (arg0, 1))
13010 && integer_zerop (op2)
13011 && integer_pow2p (arg1))
13013 tree tem = TREE_OPERAND (arg0, 0);
13015 if (TREE_CODE (tem) == RSHIFT_EXPR
13016 && TREE_CODE (TREE_OPERAND (tem, 1)) == INTEGER_CST
13017 && (unsigned HOST_WIDE_INT) tree_log2 (arg1) ==
13018 TREE_INT_CST_LOW (TREE_OPERAND (tem, 1)))
13019 return fold_build2 (BIT_AND_EXPR, type,
13020 TREE_OPERAND (tem, 0), arg1);
13023 /* A & N ? N : 0 is simply A & N if N is a power of two. This
13024 is probably obsolete because the first operand should be a
13025 truth value (that's why we have the two cases above), but let's
13026 leave it in until we can confirm this for all front-ends. */
13027 if (integer_zerop (op2)
13028 && TREE_CODE (arg0) == NE_EXPR
13029 && integer_zerop (TREE_OPERAND (arg0, 1))
13030 && integer_pow2p (arg1)
13031 && TREE_CODE (TREE_OPERAND (arg0, 0)) == BIT_AND_EXPR
13032 && operand_equal_p (TREE_OPERAND (TREE_OPERAND (arg0, 0), 1),
13033 arg1, OEP_ONLY_CONST))
13034 return pedantic_non_lvalue (fold_convert (type,
13035 TREE_OPERAND (arg0, 0)));
13037 /* Convert A ? B : 0 into A && B if A and B are truth values. */
13038 if (integer_zerop (op2)
13039 && truth_value_p (TREE_CODE (arg0))
13040 && truth_value_p (TREE_CODE (arg1)))
13041 return fold_build2 (TRUTH_ANDIF_EXPR, type,
13042 fold_convert (type, arg0),
13045 /* Convert A ? B : 1 into !A || B if A and B are truth values. */
13046 if (integer_onep (op2)
13047 && truth_value_p (TREE_CODE (arg0))
13048 && truth_value_p (TREE_CODE (arg1)))
13050 /* Only perform transformation if ARG0 is easily inverted. */
13051 tem = fold_truth_not_expr (arg0);
13053 return fold_build2 (TRUTH_ORIF_EXPR, type,
13054 fold_convert (type, tem),
13058 /* Convert A ? 0 : B into !A && B if A and B are truth values. */
13059 if (integer_zerop (arg1)
13060 && truth_value_p (TREE_CODE (arg0))
13061 && truth_value_p (TREE_CODE (op2)))
13063 /* Only perform transformation if ARG0 is easily inverted. */
13064 tem = fold_truth_not_expr (arg0);
13066 return fold_build2 (TRUTH_ANDIF_EXPR, type,
13067 fold_convert (type, tem),
13071 /* Convert A ? 1 : B into A || B if A and B are truth values. */
13072 if (integer_onep (arg1)
13073 && truth_value_p (TREE_CODE (arg0))
13074 && truth_value_p (TREE_CODE (op2)))
13075 return fold_build2 (TRUTH_ORIF_EXPR, type,
13076 fold_convert (type, arg0),
13082 /* CALL_EXPRs used to be ternary exprs. Catch any mistaken uses
13083 of fold_ternary on them. */
13084 gcc_unreachable ();
13086 case BIT_FIELD_REF:
13087 if ((TREE_CODE (arg0) == VECTOR_CST
13088 || (TREE_CODE (arg0) == CONSTRUCTOR && TREE_CONSTANT (arg0)))
13089 && type == TREE_TYPE (TREE_TYPE (arg0)))
13091 unsigned HOST_WIDE_INT width = tree_low_cst (arg1, 1);
13092 unsigned HOST_WIDE_INT idx = tree_low_cst (op2, 1);
13095 && simple_cst_equal (arg1, TYPE_SIZE (type)) == 1
13096 && (idx % width) == 0
13097 && (idx = idx / width)
13098 < TYPE_VECTOR_SUBPARTS (TREE_TYPE (arg0)))
13100 tree elements = NULL_TREE;
13102 if (TREE_CODE (arg0) == VECTOR_CST)
13103 elements = TREE_VECTOR_CST_ELTS (arg0);
13106 unsigned HOST_WIDE_INT idx;
13109 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (arg0), idx, value)
13110 elements = tree_cons (NULL_TREE, value, elements);
13112 while (idx-- > 0 && elements)
13113 elements = TREE_CHAIN (elements);
13115 return TREE_VALUE (elements);
13117 return fold_convert (type, integer_zero_node);
13124 } /* switch (code) */
13127 /* Perform constant folding and related simplification of EXPR.
13128 The related simplifications include x*1 => x, x*0 => 0, etc.,
13129 and application of the associative law.
13130 NOP_EXPR conversions may be removed freely (as long as we
13131 are careful not to change the type of the overall expression).
13132 We cannot simplify through a CONVERT_EXPR, FIX_EXPR or FLOAT_EXPR,
13133 but we can constant-fold them if they have constant operands. */
13135 #ifdef ENABLE_FOLD_CHECKING
13136 # define fold(x) fold_1 (x)
13137 static tree fold_1 (tree);
13143 const tree t = expr;
13144 enum tree_code code = TREE_CODE (t);
13145 enum tree_code_class kind = TREE_CODE_CLASS (code);
13148 /* Return right away if a constant. */
13149 if (kind == tcc_constant)
13152 /* CALL_EXPR-like objects with variable numbers of operands are
13153 treated specially. */
13154 if (kind == tcc_vl_exp)
13156 if (code == CALL_EXPR)
13158 tem = fold_call_expr (expr, false);
13159 return tem ? tem : expr;
13164 if (IS_EXPR_CODE_CLASS (kind)
13165 || IS_GIMPLE_STMT_CODE_CLASS (kind))
13167 tree type = TREE_TYPE (t);
13168 tree op0, op1, op2;
13170 switch (TREE_CODE_LENGTH (code))
13173 op0 = TREE_OPERAND (t, 0);
13174 tem = fold_unary (code, type, op0);
13175 return tem ? tem : expr;
13177 op0 = TREE_OPERAND (t, 0);
13178 op1 = TREE_OPERAND (t, 1);
13179 tem = fold_binary (code, type, op0, op1);
13180 return tem ? tem : expr;
13182 op0 = TREE_OPERAND (t, 0);
13183 op1 = TREE_OPERAND (t, 1);
13184 op2 = TREE_OPERAND (t, 2);
13185 tem = fold_ternary (code, type, op0, op1, op2);
13186 return tem ? tem : expr;
13196 tree op0 = TREE_OPERAND (t, 0);
13197 tree op1 = TREE_OPERAND (t, 1);
13199 if (TREE_CODE (op1) == INTEGER_CST
13200 && TREE_CODE (op0) == CONSTRUCTOR
13201 && ! type_contains_placeholder_p (TREE_TYPE (op0)))
13203 VEC(constructor_elt,gc) *elts = CONSTRUCTOR_ELTS (op0);
13204 unsigned HOST_WIDE_INT end = VEC_length (constructor_elt, elts);
13205 unsigned HOST_WIDE_INT begin = 0;
13207 /* Find a matching index by means of a binary search. */
13208 while (begin != end)
13210 unsigned HOST_WIDE_INT middle = (begin + end) / 2;
13211 tree index = VEC_index (constructor_elt, elts, middle)->index;
13213 if (TREE_CODE (index) == INTEGER_CST
13214 && tree_int_cst_lt (index, op1))
13215 begin = middle + 1;
13216 else if (TREE_CODE (index) == INTEGER_CST
13217 && tree_int_cst_lt (op1, index))
13219 else if (TREE_CODE (index) == RANGE_EXPR
13220 && tree_int_cst_lt (TREE_OPERAND (index, 1), op1))
13221 begin = middle + 1;
13222 else if (TREE_CODE (index) == RANGE_EXPR
13223 && tree_int_cst_lt (op1, TREE_OPERAND (index, 0)))
13226 return VEC_index (constructor_elt, elts, middle)->value;
13234 return fold (DECL_INITIAL (t));
13238 } /* switch (code) */
13241 #ifdef ENABLE_FOLD_CHECKING
13244 static void fold_checksum_tree (const_tree, struct md5_ctx *, htab_t);
13245 static void fold_check_failed (const_tree, const_tree);
13246 void print_fold_checksum (const_tree);
13248 /* When --enable-checking=fold, compute a digest of expr before
13249 and after actual fold call to see if fold did not accidentally
13250 change original expr. */
13256 struct md5_ctx ctx;
13257 unsigned char checksum_before[16], checksum_after[16];
13260 ht = htab_create (32, htab_hash_pointer, htab_eq_pointer, NULL);
13261 md5_init_ctx (&ctx);
13262 fold_checksum_tree (expr, &ctx, ht);
13263 md5_finish_ctx (&ctx, checksum_before);
13266 ret = fold_1 (expr);
13268 md5_init_ctx (&ctx);
13269 fold_checksum_tree (expr, &ctx, ht);
13270 md5_finish_ctx (&ctx, checksum_after);
13273 if (memcmp (checksum_before, checksum_after, 16))
13274 fold_check_failed (expr, ret);
13280 print_fold_checksum (const_tree expr)
13282 struct md5_ctx ctx;
13283 unsigned char checksum[16], cnt;
13286 ht = htab_create (32, htab_hash_pointer, htab_eq_pointer, NULL);
13287 md5_init_ctx (&ctx);
13288 fold_checksum_tree (expr, &ctx, ht);
13289 md5_finish_ctx (&ctx, checksum);
13291 for (cnt = 0; cnt < 16; ++cnt)
13292 fprintf (stderr, "%02x", checksum[cnt]);
13293 putc ('\n', stderr);
13297 fold_check_failed (const_tree expr ATTRIBUTE_UNUSED, const_tree ret ATTRIBUTE_UNUSED)
13299 internal_error ("fold check: original tree changed by fold");
13303 fold_checksum_tree (const_tree expr, struct md5_ctx *ctx, htab_t ht)
13306 enum tree_code code;
13307 struct tree_function_decl buf;
13312 gcc_assert ((sizeof (struct tree_exp) + 5 * sizeof (tree)
13313 <= sizeof (struct tree_function_decl))
13314 && sizeof (struct tree_type) <= sizeof (struct tree_function_decl));
13317 slot = (const void **) htab_find_slot (ht, expr, INSERT);
13321 code = TREE_CODE (expr);
13322 if (TREE_CODE_CLASS (code) == tcc_declaration
13323 && DECL_ASSEMBLER_NAME_SET_P (expr))
13325 /* Allow DECL_ASSEMBLER_NAME to be modified. */
13326 memcpy ((char *) &buf, expr, tree_size (expr));
13327 SET_DECL_ASSEMBLER_NAME ((tree)&buf, NULL);
13328 expr = (tree) &buf;
13330 else if (TREE_CODE_CLASS (code) == tcc_type
13331 && (TYPE_POINTER_TO (expr) || TYPE_REFERENCE_TO (expr)
13332 || TYPE_CACHED_VALUES_P (expr)
13333 || TYPE_CONTAINS_PLACEHOLDER_INTERNAL (expr)))
13335 /* Allow these fields to be modified. */
13337 memcpy ((char *) &buf, expr, tree_size (expr));
13338 expr = tmp = (tree) &buf;
13339 TYPE_CONTAINS_PLACEHOLDER_INTERNAL (tmp) = 0;
13340 TYPE_POINTER_TO (tmp) = NULL;
13341 TYPE_REFERENCE_TO (tmp) = NULL;
13342 if (TYPE_CACHED_VALUES_P (tmp))
13344 TYPE_CACHED_VALUES_P (tmp) = 0;
13345 TYPE_CACHED_VALUES (tmp) = NULL;
13348 md5_process_bytes (expr, tree_size (expr), ctx);
13349 fold_checksum_tree (TREE_TYPE (expr), ctx, ht);
13350 if (TREE_CODE_CLASS (code) != tcc_type
13351 && TREE_CODE_CLASS (code) != tcc_declaration
13352 && code != TREE_LIST
13353 && code != SSA_NAME)
13354 fold_checksum_tree (TREE_CHAIN (expr), ctx, ht);
13355 switch (TREE_CODE_CLASS (code))
13361 md5_process_bytes (TREE_STRING_POINTER (expr),
13362 TREE_STRING_LENGTH (expr), ctx);
13365 fold_checksum_tree (TREE_REALPART (expr), ctx, ht);
13366 fold_checksum_tree (TREE_IMAGPART (expr), ctx, ht);
13369 fold_checksum_tree (TREE_VECTOR_CST_ELTS (expr), ctx, ht);
13375 case tcc_exceptional:
13379 fold_checksum_tree (TREE_PURPOSE (expr), ctx, ht);
13380 fold_checksum_tree (TREE_VALUE (expr), ctx, ht);
13381 expr = TREE_CHAIN (expr);
13382 goto recursive_label;
13385 for (i = 0; i < TREE_VEC_LENGTH (expr); ++i)
13386 fold_checksum_tree (TREE_VEC_ELT (expr, i), ctx, ht);
13392 case tcc_expression:
13393 case tcc_reference:
13394 case tcc_comparison:
13397 case tcc_statement:
13399 len = TREE_OPERAND_LENGTH (expr);
13400 for (i = 0; i < len; ++i)
13401 fold_checksum_tree (TREE_OPERAND (expr, i), ctx, ht);
13403 case tcc_declaration:
13404 fold_checksum_tree (DECL_NAME (expr), ctx, ht);
13405 fold_checksum_tree (DECL_CONTEXT (expr), ctx, ht);
13406 if (CODE_CONTAINS_STRUCT (TREE_CODE (expr), TS_DECL_COMMON))
13408 fold_checksum_tree (DECL_SIZE (expr), ctx, ht);
13409 fold_checksum_tree (DECL_SIZE_UNIT (expr), ctx, ht);
13410 fold_checksum_tree (DECL_INITIAL (expr), ctx, ht);
13411 fold_checksum_tree (DECL_ABSTRACT_ORIGIN (expr), ctx, ht);
13412 fold_checksum_tree (DECL_ATTRIBUTES (expr), ctx, ht);
13414 if (CODE_CONTAINS_STRUCT (TREE_CODE (expr), TS_DECL_WITH_VIS))
13415 fold_checksum_tree (DECL_SECTION_NAME (expr), ctx, ht);
13417 if (CODE_CONTAINS_STRUCT (TREE_CODE (expr), TS_DECL_NON_COMMON))
13419 fold_checksum_tree (DECL_VINDEX (expr), ctx, ht);
13420 fold_checksum_tree (DECL_RESULT_FLD (expr), ctx, ht);
13421 fold_checksum_tree (DECL_ARGUMENT_FLD (expr), ctx, ht);
13425 if (TREE_CODE (expr) == ENUMERAL_TYPE)
13426 fold_checksum_tree (TYPE_VALUES (expr), ctx, ht);
13427 fold_checksum_tree (TYPE_SIZE (expr), ctx, ht);
13428 fold_checksum_tree (TYPE_SIZE_UNIT (expr), ctx, ht);
13429 fold_checksum_tree (TYPE_ATTRIBUTES (expr), ctx, ht);
13430 fold_checksum_tree (TYPE_NAME (expr), ctx, ht);
13431 if (INTEGRAL_TYPE_P (expr)
13432 || SCALAR_FLOAT_TYPE_P (expr))
13434 fold_checksum_tree (TYPE_MIN_VALUE (expr), ctx, ht);
13435 fold_checksum_tree (TYPE_MAX_VALUE (expr), ctx, ht);
13437 fold_checksum_tree (TYPE_MAIN_VARIANT (expr), ctx, ht);
13438 if (TREE_CODE (expr) == RECORD_TYPE
13439 || TREE_CODE (expr) == UNION_TYPE
13440 || TREE_CODE (expr) == QUAL_UNION_TYPE)
13441 fold_checksum_tree (TYPE_BINFO (expr), ctx, ht);
13442 fold_checksum_tree (TYPE_CONTEXT (expr), ctx, ht);
13449 /* Helper function for outputting the checksum of a tree T. When
13450 debugging with gdb, you can "define mynext" to be "next" followed
13451 by "call debug_fold_checksum (op0)", then just trace down till the
13455 debug_fold_checksum (const_tree t)
13458 unsigned char checksum[16];
13459 struct md5_ctx ctx;
13460 htab_t ht = htab_create (32, htab_hash_pointer, htab_eq_pointer, NULL);
13462 md5_init_ctx (&ctx);
13463 fold_checksum_tree (t, &ctx, ht);
13464 md5_finish_ctx (&ctx, checksum);
13467 for (i = 0; i < 16; i++)
13468 fprintf (stderr, "%d ", checksum[i]);
13470 fprintf (stderr, "\n");
13475 /* Fold a unary tree expression with code CODE of type TYPE with an
13476 operand OP0. Return a folded expression if successful. Otherwise,
13477 return a tree expression with code CODE of type TYPE with an
13481 fold_build1_stat (enum tree_code code, tree type, tree op0 MEM_STAT_DECL)
13484 #ifdef ENABLE_FOLD_CHECKING
13485 unsigned char checksum_before[16], checksum_after[16];
13486 struct md5_ctx ctx;
13489 ht = htab_create (32, htab_hash_pointer, htab_eq_pointer, NULL);
13490 md5_init_ctx (&ctx);
13491 fold_checksum_tree (op0, &ctx, ht);
13492 md5_finish_ctx (&ctx, checksum_before);
13496 tem = fold_unary (code, type, op0);
13498 tem = build1_stat (code, type, op0 PASS_MEM_STAT);
13500 #ifdef ENABLE_FOLD_CHECKING
13501 md5_init_ctx (&ctx);
13502 fold_checksum_tree (op0, &ctx, ht);
13503 md5_finish_ctx (&ctx, checksum_after);
13506 if (memcmp (checksum_before, checksum_after, 16))
13507 fold_check_failed (op0, tem);
13512 /* Fold a binary tree expression with code CODE of type TYPE with
13513 operands OP0 and OP1. Return a folded expression if successful.
13514 Otherwise, return a tree expression with code CODE of type TYPE
13515 with operands OP0 and OP1. */
13518 fold_build2_stat (enum tree_code code, tree type, tree op0, tree op1
13522 #ifdef ENABLE_FOLD_CHECKING
13523 unsigned char checksum_before_op0[16],
13524 checksum_before_op1[16],
13525 checksum_after_op0[16],
13526 checksum_after_op1[16];
13527 struct md5_ctx ctx;
13530 ht = htab_create (32, htab_hash_pointer, htab_eq_pointer, NULL);
13531 md5_init_ctx (&ctx);
13532 fold_checksum_tree (op0, &ctx, ht);
13533 md5_finish_ctx (&ctx, checksum_before_op0);
13536 md5_init_ctx (&ctx);
13537 fold_checksum_tree (op1, &ctx, ht);
13538 md5_finish_ctx (&ctx, checksum_before_op1);
13542 tem = fold_binary (code, type, op0, op1);
13544 tem = build2_stat (code, type, op0, op1 PASS_MEM_STAT);
13546 #ifdef ENABLE_FOLD_CHECKING
13547 md5_init_ctx (&ctx);
13548 fold_checksum_tree (op0, &ctx, ht);
13549 md5_finish_ctx (&ctx, checksum_after_op0);
13552 if (memcmp (checksum_before_op0, checksum_after_op0, 16))
13553 fold_check_failed (op0, tem);
13555 md5_init_ctx (&ctx);
13556 fold_checksum_tree (op1, &ctx, ht);
13557 md5_finish_ctx (&ctx, checksum_after_op1);
13560 if (memcmp (checksum_before_op1, checksum_after_op1, 16))
13561 fold_check_failed (op1, tem);
13566 /* Fold a ternary tree expression with code CODE of type TYPE with
13567 operands OP0, OP1, and OP2. Return a folded expression if
13568 successful. Otherwise, return a tree expression with code CODE of
13569 type TYPE with operands OP0, OP1, and OP2. */
13572 fold_build3_stat (enum tree_code code, tree type, tree op0, tree op1, tree op2
13576 #ifdef ENABLE_FOLD_CHECKING
13577 unsigned char checksum_before_op0[16],
13578 checksum_before_op1[16],
13579 checksum_before_op2[16],
13580 checksum_after_op0[16],
13581 checksum_after_op1[16],
13582 checksum_after_op2[16];
13583 struct md5_ctx ctx;
13586 ht = htab_create (32, htab_hash_pointer, htab_eq_pointer, NULL);
13587 md5_init_ctx (&ctx);
13588 fold_checksum_tree (op0, &ctx, ht);
13589 md5_finish_ctx (&ctx, checksum_before_op0);
13592 md5_init_ctx (&ctx);
13593 fold_checksum_tree (op1, &ctx, ht);
13594 md5_finish_ctx (&ctx, checksum_before_op1);
13597 md5_init_ctx (&ctx);
13598 fold_checksum_tree (op2, &ctx, ht);
13599 md5_finish_ctx (&ctx, checksum_before_op2);
13603 gcc_assert (TREE_CODE_CLASS (code) != tcc_vl_exp);
13604 tem = fold_ternary (code, type, op0, op1, op2);
13606 tem = build3_stat (code, type, op0, op1, op2 PASS_MEM_STAT);
13608 #ifdef ENABLE_FOLD_CHECKING
13609 md5_init_ctx (&ctx);
13610 fold_checksum_tree (op0, &ctx, ht);
13611 md5_finish_ctx (&ctx, checksum_after_op0);
13614 if (memcmp (checksum_before_op0, checksum_after_op0, 16))
13615 fold_check_failed (op0, tem);
13617 md5_init_ctx (&ctx);
13618 fold_checksum_tree (op1, &ctx, ht);
13619 md5_finish_ctx (&ctx, checksum_after_op1);
13622 if (memcmp (checksum_before_op1, checksum_after_op1, 16))
13623 fold_check_failed (op1, tem);
13625 md5_init_ctx (&ctx);
13626 fold_checksum_tree (op2, &ctx, ht);
13627 md5_finish_ctx (&ctx, checksum_after_op2);
13630 if (memcmp (checksum_before_op2, checksum_after_op2, 16))
13631 fold_check_failed (op2, tem);
13636 /* Fold a CALL_EXPR expression of type TYPE with operands FN and NARGS
13637 arguments in ARGARRAY, and a null static chain.
13638 Return a folded expression if successful. Otherwise, return a CALL_EXPR
13639 of type TYPE from the given operands as constructed by build_call_array. */
13642 fold_build_call_array (tree type, tree fn, int nargs, tree *argarray)
13645 #ifdef ENABLE_FOLD_CHECKING
13646 unsigned char checksum_before_fn[16],
13647 checksum_before_arglist[16],
13648 checksum_after_fn[16],
13649 checksum_after_arglist[16];
13650 struct md5_ctx ctx;
13654 ht = htab_create (32, htab_hash_pointer, htab_eq_pointer, NULL);
13655 md5_init_ctx (&ctx);
13656 fold_checksum_tree (fn, &ctx, ht);
13657 md5_finish_ctx (&ctx, checksum_before_fn);
13660 md5_init_ctx (&ctx);
13661 for (i = 0; i < nargs; i++)
13662 fold_checksum_tree (argarray[i], &ctx, ht);
13663 md5_finish_ctx (&ctx, checksum_before_arglist);
13667 tem = fold_builtin_call_array (type, fn, nargs, argarray);
13669 #ifdef ENABLE_FOLD_CHECKING
13670 md5_init_ctx (&ctx);
13671 fold_checksum_tree (fn, &ctx, ht);
13672 md5_finish_ctx (&ctx, checksum_after_fn);
13675 if (memcmp (checksum_before_fn, checksum_after_fn, 16))
13676 fold_check_failed (fn, tem);
13678 md5_init_ctx (&ctx);
13679 for (i = 0; i < nargs; i++)
13680 fold_checksum_tree (argarray[i], &ctx, ht);
13681 md5_finish_ctx (&ctx, checksum_after_arglist);
13684 if (memcmp (checksum_before_arglist, checksum_after_arglist, 16))
13685 fold_check_failed (NULL_TREE, tem);
13690 /* Perform constant folding and related simplification of initializer
13691 expression EXPR. These behave identically to "fold_buildN" but ignore
13692 potential run-time traps and exceptions that fold must preserve. */
13694 #define START_FOLD_INIT \
13695 int saved_signaling_nans = flag_signaling_nans;\
13696 int saved_trapping_math = flag_trapping_math;\
13697 int saved_rounding_math = flag_rounding_math;\
13698 int saved_trapv = flag_trapv;\
13699 int saved_folding_initializer = folding_initializer;\
13700 flag_signaling_nans = 0;\
13701 flag_trapping_math = 0;\
13702 flag_rounding_math = 0;\
13704 folding_initializer = 1;
13706 #define END_FOLD_INIT \
13707 flag_signaling_nans = saved_signaling_nans;\
13708 flag_trapping_math = saved_trapping_math;\
13709 flag_rounding_math = saved_rounding_math;\
13710 flag_trapv = saved_trapv;\
13711 folding_initializer = saved_folding_initializer;
13714 fold_build1_initializer (enum tree_code code, tree type, tree op)
13719 result = fold_build1 (code, type, op);
13726 fold_build2_initializer (enum tree_code code, tree type, tree op0, tree op1)
13731 result = fold_build2 (code, type, op0, op1);
13738 fold_build3_initializer (enum tree_code code, tree type, tree op0, tree op1,
13744 result = fold_build3 (code, type, op0, op1, op2);
13751 fold_build_call_array_initializer (tree type, tree fn,
13752 int nargs, tree *argarray)
13757 result = fold_build_call_array (type, fn, nargs, argarray);
13763 #undef START_FOLD_INIT
13764 #undef END_FOLD_INIT
13766 /* Determine if first argument is a multiple of second argument. Return 0 if
13767 it is not, or we cannot easily determined it to be.
13769 An example of the sort of thing we care about (at this point; this routine
13770 could surely be made more general, and expanded to do what the *_DIV_EXPR's
13771 fold cases do now) is discovering that
13773 SAVE_EXPR (I) * SAVE_EXPR (J * 8)
13779 when we know that the two SAVE_EXPR (J * 8) nodes are the same node.
13781 This code also handles discovering that
13783 SAVE_EXPR (I) * SAVE_EXPR (J * 8)
13785 is a multiple of 8 so we don't have to worry about dealing with a
13786 possible remainder.
13788 Note that we *look* inside a SAVE_EXPR only to determine how it was
13789 calculated; it is not safe for fold to do much of anything else with the
13790 internals of a SAVE_EXPR, since it cannot know when it will be evaluated
13791 at run time. For example, the latter example above *cannot* be implemented
13792 as SAVE_EXPR (I) * J or any variant thereof, since the value of J at
13793 evaluation time of the original SAVE_EXPR is not necessarily the same at
13794 the time the new expression is evaluated. The only optimization of this
13795 sort that would be valid is changing
13797 SAVE_EXPR (I) * SAVE_EXPR (SAVE_EXPR (J) * 8)
13801 SAVE_EXPR (I) * SAVE_EXPR (J)
13803 (where the same SAVE_EXPR (J) is used in the original and the
13804 transformed version). */
13807 multiple_of_p (tree type, const_tree top, const_tree bottom)
13809 if (operand_equal_p (top, bottom, 0))
13812 if (TREE_CODE (type) != INTEGER_TYPE)
13815 switch (TREE_CODE (top))
13818 /* Bitwise and provides a power of two multiple. If the mask is
13819 a multiple of BOTTOM then TOP is a multiple of BOTTOM. */
13820 if (!integer_pow2p (bottom))
13825 return (multiple_of_p (type, TREE_OPERAND (top, 0), bottom)
13826 || multiple_of_p (type, TREE_OPERAND (top, 1), bottom));
13830 return (multiple_of_p (type, TREE_OPERAND (top, 0), bottom)
13831 && multiple_of_p (type, TREE_OPERAND (top, 1), bottom));
13834 if (TREE_CODE (TREE_OPERAND (top, 1)) == INTEGER_CST)
13838 op1 = TREE_OPERAND (top, 1);
13839 /* const_binop may not detect overflow correctly,
13840 so check for it explicitly here. */
13841 if (TYPE_PRECISION (TREE_TYPE (size_one_node))
13842 > TREE_INT_CST_LOW (op1)
13843 && TREE_INT_CST_HIGH (op1) == 0
13844 && 0 != (t1 = fold_convert (type,
13845 const_binop (LSHIFT_EXPR,
13848 && !TREE_OVERFLOW (t1))
13849 return multiple_of_p (type, t1, bottom);
13854 /* Can't handle conversions from non-integral or wider integral type. */
13855 if ((TREE_CODE (TREE_TYPE (TREE_OPERAND (top, 0))) != INTEGER_TYPE)
13856 || (TYPE_PRECISION (type)
13857 < TYPE_PRECISION (TREE_TYPE (TREE_OPERAND (top, 0)))))
13860 /* .. fall through ... */
13863 return multiple_of_p (type, TREE_OPERAND (top, 0), bottom);
13866 if (TREE_CODE (bottom) != INTEGER_CST
13867 || integer_zerop (bottom)
13868 || (TYPE_UNSIGNED (type)
13869 && (tree_int_cst_sgn (top) < 0
13870 || tree_int_cst_sgn (bottom) < 0)))
13872 return integer_zerop (int_const_binop (TRUNC_MOD_EXPR,
13880 /* Return true if CODE or TYPE is known to be non-negative. */
13883 tree_simple_nonnegative_warnv_p (enum tree_code code, tree type)
13885 if ((TYPE_PRECISION (type) != 1 || TYPE_UNSIGNED (type))
13886 && truth_value_p (code))
13887 /* Truth values evaluate to 0 or 1, which is nonnegative unless we
13888 have a signed:1 type (where the value is -1 and 0). */
13893 /* Return true if (CODE OP0) is known to be non-negative. If the return
13894 value is based on the assumption that signed overflow is undefined,
13895 set *STRICT_OVERFLOW_P to true; otherwise, don't change
13896 *STRICT_OVERFLOW_P. */
13899 tree_unary_nonnegative_warnv_p (enum tree_code code, tree type, tree op0,
13900 bool *strict_overflow_p)
13902 if (TYPE_UNSIGNED (type))
13908 /* We can't return 1 if flag_wrapv is set because
13909 ABS_EXPR<INT_MIN> = INT_MIN. */
13910 if (!INTEGRAL_TYPE_P (type))
13912 if (TYPE_OVERFLOW_UNDEFINED (type))
13914 *strict_overflow_p = true;
13919 case NON_LVALUE_EXPR:
13921 case FIX_TRUNC_EXPR:
13922 return tree_expr_nonnegative_warnv_p (op0,
13923 strict_overflow_p);
13927 tree inner_type = TREE_TYPE (op0);
13928 tree outer_type = type;
13930 if (TREE_CODE (outer_type) == REAL_TYPE)
13932 if (TREE_CODE (inner_type) == REAL_TYPE)
13933 return tree_expr_nonnegative_warnv_p (op0,
13934 strict_overflow_p);
13935 if (TREE_CODE (inner_type) == INTEGER_TYPE)
13937 if (TYPE_UNSIGNED (inner_type))
13939 return tree_expr_nonnegative_warnv_p (op0,
13940 strict_overflow_p);
13943 else if (TREE_CODE (outer_type) == INTEGER_TYPE)
13945 if (TREE_CODE (inner_type) == REAL_TYPE)
13946 return tree_expr_nonnegative_warnv_p (op0,
13947 strict_overflow_p);
13948 if (TREE_CODE (inner_type) == INTEGER_TYPE)
13949 return TYPE_PRECISION (inner_type) < TYPE_PRECISION (outer_type)
13950 && TYPE_UNSIGNED (inner_type);
13956 return tree_simple_nonnegative_warnv_p (code, type);
13959 /* We don't know sign of `t', so be conservative and return false. */
13963 /* Return true if (CODE OP0 OP1) is known to be non-negative. If the return
13964 value is based on the assumption that signed overflow is undefined,
13965 set *STRICT_OVERFLOW_P to true; otherwise, don't change
13966 *STRICT_OVERFLOW_P. */
13969 tree_binary_nonnegative_warnv_p (enum tree_code code, tree type, tree op0,
13970 tree op1, bool *strict_overflow_p)
13972 if (TYPE_UNSIGNED (type))
13977 case POINTER_PLUS_EXPR:
13979 if (FLOAT_TYPE_P (type))
13980 return (tree_expr_nonnegative_warnv_p (op0,
13982 && tree_expr_nonnegative_warnv_p (op1,
13983 strict_overflow_p));
13985 /* zero_extend(x) + zero_extend(y) is non-negative if x and y are
13986 both unsigned and at least 2 bits shorter than the result. */
13987 if (TREE_CODE (type) == INTEGER_TYPE
13988 && TREE_CODE (op0) == NOP_EXPR
13989 && TREE_CODE (op1) == NOP_EXPR)
13991 tree inner1 = TREE_TYPE (TREE_OPERAND (op0, 0));
13992 tree inner2 = TREE_TYPE (TREE_OPERAND (op1, 0));
13993 if (TREE_CODE (inner1) == INTEGER_TYPE && TYPE_UNSIGNED (inner1)
13994 && TREE_CODE (inner2) == INTEGER_TYPE && TYPE_UNSIGNED (inner2))
13996 unsigned int prec = MAX (TYPE_PRECISION (inner1),
13997 TYPE_PRECISION (inner2)) + 1;
13998 return prec < TYPE_PRECISION (type);
14004 if (FLOAT_TYPE_P (type))
14006 /* x * x for floating point x is always non-negative. */
14007 if (operand_equal_p (op0, op1, 0))
14009 return (tree_expr_nonnegative_warnv_p (op0,
14011 && tree_expr_nonnegative_warnv_p (op1,
14012 strict_overflow_p));
14015 /* zero_extend(x) * zero_extend(y) is non-negative if x and y are
14016 both unsigned and their total bits is shorter than the result. */
14017 if (TREE_CODE (type) == INTEGER_TYPE
14018 && TREE_CODE (op0) == NOP_EXPR
14019 && TREE_CODE (op1) == NOP_EXPR)
14021 tree inner1 = TREE_TYPE (TREE_OPERAND (op0, 0));
14022 tree inner2 = TREE_TYPE (TREE_OPERAND (op1, 0));
14023 if (TREE_CODE (inner1) == INTEGER_TYPE && TYPE_UNSIGNED (inner1)
14024 && TREE_CODE (inner2) == INTEGER_TYPE && TYPE_UNSIGNED (inner2))
14025 return TYPE_PRECISION (inner1) + TYPE_PRECISION (inner2)
14026 < TYPE_PRECISION (type);
14032 return (tree_expr_nonnegative_warnv_p (op0,
14034 || tree_expr_nonnegative_warnv_p (op1,
14035 strict_overflow_p));
14041 case TRUNC_DIV_EXPR:
14042 case CEIL_DIV_EXPR:
14043 case FLOOR_DIV_EXPR:
14044 case ROUND_DIV_EXPR:
14045 return (tree_expr_nonnegative_warnv_p (op0,
14047 && tree_expr_nonnegative_warnv_p (op1,
14048 strict_overflow_p));
14050 case TRUNC_MOD_EXPR:
14051 case CEIL_MOD_EXPR:
14052 case FLOOR_MOD_EXPR:
14053 case ROUND_MOD_EXPR:
14054 return tree_expr_nonnegative_warnv_p (op0,
14055 strict_overflow_p);
14057 return tree_simple_nonnegative_warnv_p (code, type);
14060 /* We don't know sign of `t', so be conservative and return false. */
14064 /* Return true if T is known to be non-negative. If the return
14065 value is based on the assumption that signed overflow is undefined,
14066 set *STRICT_OVERFLOW_P to true; otherwise, don't change
14067 *STRICT_OVERFLOW_P. */
14070 tree_single_nonnegative_warnv_p (tree t, bool *strict_overflow_p)
14072 if (TYPE_UNSIGNED (TREE_TYPE (t)))
14075 switch (TREE_CODE (t))
14078 /* Query VRP to see if it has recorded any information about
14079 the range of this object. */
14080 return ssa_name_nonnegative_p (t);
14083 return tree_int_cst_sgn (t) >= 0;
14086 return ! REAL_VALUE_NEGATIVE (TREE_REAL_CST (t));
14089 return ! FIXED_VALUE_NEGATIVE (TREE_FIXED_CST (t));
14092 return (tree_expr_nonnegative_warnv_p (TREE_OPERAND (t, 1),
14094 && tree_expr_nonnegative_warnv_p (TREE_OPERAND (t, 2),
14095 strict_overflow_p));
14097 return tree_simple_nonnegative_warnv_p (TREE_CODE (t),
14100 /* We don't know sign of `t', so be conservative and return false. */
14104 /* Return true if T is known to be non-negative. If the return
14105 value is based on the assumption that signed overflow is undefined,
14106 set *STRICT_OVERFLOW_P to true; otherwise, don't change
14107 *STRICT_OVERFLOW_P. */
14110 tree_call_nonnegative_warnv_p (enum tree_code code, tree type, tree fndecl,
14111 tree arg0, tree arg1, bool *strict_overflow_p)
14113 if (fndecl && DECL_BUILT_IN_CLASS (fndecl) == BUILT_IN_NORMAL)
14114 switch (DECL_FUNCTION_CODE (fndecl))
14116 CASE_FLT_FN (BUILT_IN_ACOS):
14117 CASE_FLT_FN (BUILT_IN_ACOSH):
14118 CASE_FLT_FN (BUILT_IN_CABS):
14119 CASE_FLT_FN (BUILT_IN_COSH):
14120 CASE_FLT_FN (BUILT_IN_ERFC):
14121 CASE_FLT_FN (BUILT_IN_EXP):
14122 CASE_FLT_FN (BUILT_IN_EXP10):
14123 CASE_FLT_FN (BUILT_IN_EXP2):
14124 CASE_FLT_FN (BUILT_IN_FABS):
14125 CASE_FLT_FN (BUILT_IN_FDIM):
14126 CASE_FLT_FN (BUILT_IN_HYPOT):
14127 CASE_FLT_FN (BUILT_IN_POW10):
14128 CASE_INT_FN (BUILT_IN_FFS):
14129 CASE_INT_FN (BUILT_IN_PARITY):
14130 CASE_INT_FN (BUILT_IN_POPCOUNT):
14131 case BUILT_IN_BSWAP32:
14132 case BUILT_IN_BSWAP64:
14136 CASE_FLT_FN (BUILT_IN_SQRT):
14137 /* sqrt(-0.0) is -0.0. */
14138 if (!HONOR_SIGNED_ZEROS (TYPE_MODE (type)))
14140 return tree_expr_nonnegative_warnv_p (arg0,
14141 strict_overflow_p);
14143 CASE_FLT_FN (BUILT_IN_ASINH):
14144 CASE_FLT_FN (BUILT_IN_ATAN):
14145 CASE_FLT_FN (BUILT_IN_ATANH):
14146 CASE_FLT_FN (BUILT_IN_CBRT):
14147 CASE_FLT_FN (BUILT_IN_CEIL):
14148 CASE_FLT_FN (BUILT_IN_ERF):
14149 CASE_FLT_FN (BUILT_IN_EXPM1):
14150 CASE_FLT_FN (BUILT_IN_FLOOR):
14151 CASE_FLT_FN (BUILT_IN_FMOD):
14152 CASE_FLT_FN (BUILT_IN_FREXP):
14153 CASE_FLT_FN (BUILT_IN_LCEIL):
14154 CASE_FLT_FN (BUILT_IN_LDEXP):
14155 CASE_FLT_FN (BUILT_IN_LFLOOR):
14156 CASE_FLT_FN (BUILT_IN_LLCEIL):
14157 CASE_FLT_FN (BUILT_IN_LLFLOOR):
14158 CASE_FLT_FN (BUILT_IN_LLRINT):
14159 CASE_FLT_FN (BUILT_IN_LLROUND):
14160 CASE_FLT_FN (BUILT_IN_LRINT):
14161 CASE_FLT_FN (BUILT_IN_LROUND):
14162 CASE_FLT_FN (BUILT_IN_MODF):
14163 CASE_FLT_FN (BUILT_IN_NEARBYINT):
14164 CASE_FLT_FN (BUILT_IN_RINT):
14165 CASE_FLT_FN (BUILT_IN_ROUND):
14166 CASE_FLT_FN (BUILT_IN_SCALB):
14167 CASE_FLT_FN (BUILT_IN_SCALBLN):
14168 CASE_FLT_FN (BUILT_IN_SCALBN):
14169 CASE_FLT_FN (BUILT_IN_SIGNBIT):
14170 CASE_FLT_FN (BUILT_IN_SIGNIFICAND):
14171 CASE_FLT_FN (BUILT_IN_SINH):
14172 CASE_FLT_FN (BUILT_IN_TANH):
14173 CASE_FLT_FN (BUILT_IN_TRUNC):
14174 /* True if the 1st argument is nonnegative. */
14175 return tree_expr_nonnegative_warnv_p (arg0,
14176 strict_overflow_p);
14178 CASE_FLT_FN (BUILT_IN_FMAX):
14179 /* True if the 1st OR 2nd arguments are nonnegative. */
14180 return (tree_expr_nonnegative_warnv_p (arg0,
14182 || (tree_expr_nonnegative_warnv_p (arg1,
14183 strict_overflow_p)));
14185 CASE_FLT_FN (BUILT_IN_FMIN):
14186 /* True if the 1st AND 2nd arguments are nonnegative. */
14187 return (tree_expr_nonnegative_warnv_p (arg0,
14189 && (tree_expr_nonnegative_warnv_p (arg1,
14190 strict_overflow_p)));
14192 CASE_FLT_FN (BUILT_IN_COPYSIGN):
14193 /* True if the 2nd argument is nonnegative. */
14194 return tree_expr_nonnegative_warnv_p (arg1,
14195 strict_overflow_p);
14197 CASE_FLT_FN (BUILT_IN_POWI):
14198 /* True if the 1st argument is nonnegative or the second
14199 argument is an even integer. */
14200 if (TREE_CODE (arg1) == INTEGER_CST
14201 && (TREE_INT_CST_LOW (arg1) & 1) == 0)
14203 return tree_expr_nonnegative_warnv_p (arg0,
14204 strict_overflow_p);
14206 CASE_FLT_FN (BUILT_IN_POW):
14207 /* True if the 1st argument is nonnegative or the second
14208 argument is an even integer valued real. */
14209 if (TREE_CODE (arg1) == REAL_CST)
14214 c = TREE_REAL_CST (arg1);
14215 n = real_to_integer (&c);
14218 REAL_VALUE_TYPE cint;
14219 real_from_integer (&cint, VOIDmode, n,
14220 n < 0 ? -1 : 0, 0);
14221 if (real_identical (&c, &cint))
14225 return tree_expr_nonnegative_warnv_p (arg0,
14226 strict_overflow_p);
14231 return tree_simple_nonnegative_warnv_p (code,
14235 /* Return true if T is known to be non-negative. If the return
14236 value is based on the assumption that signed overflow is undefined,
14237 set *STRICT_OVERFLOW_P to true; otherwise, don't change
14238 *STRICT_OVERFLOW_P. */
14241 tree_invalid_nonnegative_warnv_p (tree t, bool *strict_overflow_p)
14243 enum tree_code code = TREE_CODE (t);
14244 if (TYPE_UNSIGNED (TREE_TYPE (t)))
14251 tree temp = TARGET_EXPR_SLOT (t);
14252 t = TARGET_EXPR_INITIAL (t);
14254 /* If the initializer is non-void, then it's a normal expression
14255 that will be assigned to the slot. */
14256 if (!VOID_TYPE_P (t))
14257 return tree_expr_nonnegative_warnv_p (t, strict_overflow_p);
14259 /* Otherwise, the initializer sets the slot in some way. One common
14260 way is an assignment statement at the end of the initializer. */
14263 if (TREE_CODE (t) == BIND_EXPR)
14264 t = expr_last (BIND_EXPR_BODY (t));
14265 else if (TREE_CODE (t) == TRY_FINALLY_EXPR
14266 || TREE_CODE (t) == TRY_CATCH_EXPR)
14267 t = expr_last (TREE_OPERAND (t, 0));
14268 else if (TREE_CODE (t) == STATEMENT_LIST)
14273 if ((TREE_CODE (t) == MODIFY_EXPR
14274 || TREE_CODE (t) == GIMPLE_MODIFY_STMT)
14275 && GENERIC_TREE_OPERAND (t, 0) == temp)
14276 return tree_expr_nonnegative_warnv_p (GENERIC_TREE_OPERAND (t, 1),
14277 strict_overflow_p);
14284 tree arg0 = call_expr_nargs (t) > 0 ? CALL_EXPR_ARG (t, 0) : NULL_TREE;
14285 tree arg1 = call_expr_nargs (t) > 1 ? CALL_EXPR_ARG (t, 1) : NULL_TREE;
14287 return tree_call_nonnegative_warnv_p (TREE_CODE (t),
14289 get_callee_fndecl (t),
14292 strict_overflow_p);
14294 case COMPOUND_EXPR:
14296 case GIMPLE_MODIFY_STMT:
14297 return tree_expr_nonnegative_warnv_p (GENERIC_TREE_OPERAND (t, 1),
14298 strict_overflow_p);
14300 return tree_expr_nonnegative_warnv_p (expr_last (TREE_OPERAND (t, 1)),
14301 strict_overflow_p);
14303 return tree_expr_nonnegative_warnv_p (TREE_OPERAND (t, 0),
14304 strict_overflow_p);
14307 return tree_simple_nonnegative_warnv_p (TREE_CODE (t),
14311 /* We don't know sign of `t', so be conservative and return false. */
14315 /* Return true if T is known to be non-negative. If the return
14316 value is based on the assumption that signed overflow is undefined,
14317 set *STRICT_OVERFLOW_P to true; otherwise, don't change
14318 *STRICT_OVERFLOW_P. */
14321 tree_expr_nonnegative_warnv_p (tree t, bool *strict_overflow_p)
14323 enum tree_code code;
14324 if (t == error_mark_node)
14327 code = TREE_CODE (t);
14328 switch (TREE_CODE_CLASS (code))
14331 case tcc_comparison:
14332 return tree_binary_nonnegative_warnv_p (TREE_CODE (t),
14334 TREE_OPERAND (t, 0),
14335 TREE_OPERAND (t, 1),
14336 strict_overflow_p);
14339 return tree_unary_nonnegative_warnv_p (TREE_CODE (t),
14341 TREE_OPERAND (t, 0),
14342 strict_overflow_p);
14345 case tcc_declaration:
14346 case tcc_reference:
14347 return tree_single_nonnegative_warnv_p (t, strict_overflow_p);
14355 case TRUTH_AND_EXPR:
14356 case TRUTH_OR_EXPR:
14357 case TRUTH_XOR_EXPR:
14358 return tree_binary_nonnegative_warnv_p (TREE_CODE (t),
14360 TREE_OPERAND (t, 0),
14361 TREE_OPERAND (t, 1),
14362 strict_overflow_p);
14363 case TRUTH_NOT_EXPR:
14364 return tree_unary_nonnegative_warnv_p (TREE_CODE (t),
14366 TREE_OPERAND (t, 0),
14367 strict_overflow_p);
14374 case WITH_SIZE_EXPR:
14378 return tree_single_nonnegative_warnv_p (t, strict_overflow_p);
14381 return tree_invalid_nonnegative_warnv_p (t, strict_overflow_p);
14385 /* Return true if `t' is known to be non-negative. Handle warnings
14386 about undefined signed overflow. */
14389 tree_expr_nonnegative_p (tree t)
14391 bool ret, strict_overflow_p;
14393 strict_overflow_p = false;
14394 ret = tree_expr_nonnegative_warnv_p (t, &strict_overflow_p);
14395 if (strict_overflow_p)
14396 fold_overflow_warning (("assuming signed overflow does not occur when "
14397 "determining that expression is always "
14399 WARN_STRICT_OVERFLOW_MISC);
14404 /* Return true when (CODE OP0) is an address and is known to be nonzero.
14405 For floating point we further ensure that T is not denormal.
14406 Similar logic is present in nonzero_address in rtlanal.h.
14408 If the return value is based on the assumption that signed overflow
14409 is undefined, set *STRICT_OVERFLOW_P to true; otherwise, don't
14410 change *STRICT_OVERFLOW_P. */
14413 tree_unary_nonzero_warnv_p (enum tree_code code, tree type, tree op0,
14414 bool *strict_overflow_p)
14419 return tree_expr_nonzero_warnv_p (op0,
14420 strict_overflow_p);
14424 tree inner_type = TREE_TYPE (op0);
14425 tree outer_type = type;
14427 return (TYPE_PRECISION (outer_type) >= TYPE_PRECISION (inner_type)
14428 && tree_expr_nonzero_warnv_p (op0,
14429 strict_overflow_p));
14433 case NON_LVALUE_EXPR:
14434 return tree_expr_nonzero_warnv_p (op0,
14435 strict_overflow_p);
14444 /* Return true when (CODE OP0 OP1) is an address and is known to be nonzero.
14445 For floating point we further ensure that T is not denormal.
14446 Similar logic is present in nonzero_address in rtlanal.h.
14448 If the return value is based on the assumption that signed overflow
14449 is undefined, set *STRICT_OVERFLOW_P to true; otherwise, don't
14450 change *STRICT_OVERFLOW_P. */
14453 tree_binary_nonzero_warnv_p (enum tree_code code,
14456 tree op1, bool *strict_overflow_p)
14458 bool sub_strict_overflow_p;
14461 case POINTER_PLUS_EXPR:
14463 if (TYPE_OVERFLOW_UNDEFINED (type))
14465 /* With the presence of negative values it is hard
14466 to say something. */
14467 sub_strict_overflow_p = false;
14468 if (!tree_expr_nonnegative_warnv_p (op0,
14469 &sub_strict_overflow_p)
14470 || !tree_expr_nonnegative_warnv_p (op1,
14471 &sub_strict_overflow_p))
14473 /* One of operands must be positive and the other non-negative. */
14474 /* We don't set *STRICT_OVERFLOW_P here: even if this value
14475 overflows, on a twos-complement machine the sum of two
14476 nonnegative numbers can never be zero. */
14477 return (tree_expr_nonzero_warnv_p (op0,
14479 || tree_expr_nonzero_warnv_p (op1,
14480 strict_overflow_p));
14485 if (TYPE_OVERFLOW_UNDEFINED (type))
14487 if (tree_expr_nonzero_warnv_p (op0,
14489 && tree_expr_nonzero_warnv_p (op1,
14490 strict_overflow_p))
14492 *strict_overflow_p = true;
14499 sub_strict_overflow_p = false;
14500 if (tree_expr_nonzero_warnv_p (op0,
14501 &sub_strict_overflow_p)
14502 && tree_expr_nonzero_warnv_p (op1,
14503 &sub_strict_overflow_p))
14505 if (sub_strict_overflow_p)
14506 *strict_overflow_p = true;
14511 sub_strict_overflow_p = false;
14512 if (tree_expr_nonzero_warnv_p (op0,
14513 &sub_strict_overflow_p))
14515 if (sub_strict_overflow_p)
14516 *strict_overflow_p = true;
14518 /* When both operands are nonzero, then MAX must be too. */
14519 if (tree_expr_nonzero_warnv_p (op1,
14520 strict_overflow_p))
14523 /* MAX where operand 0 is positive is positive. */
14524 return tree_expr_nonnegative_warnv_p (op0,
14525 strict_overflow_p);
14527 /* MAX where operand 1 is positive is positive. */
14528 else if (tree_expr_nonzero_warnv_p (op1,
14529 &sub_strict_overflow_p)
14530 && tree_expr_nonnegative_warnv_p (op1,
14531 &sub_strict_overflow_p))
14533 if (sub_strict_overflow_p)
14534 *strict_overflow_p = true;
14540 return (tree_expr_nonzero_warnv_p (op1,
14542 || tree_expr_nonzero_warnv_p (op0,
14543 strict_overflow_p));
14552 /* Return true when T is an address and is known to be nonzero.
14553 For floating point we further ensure that T is not denormal.
14554 Similar logic is present in nonzero_address in rtlanal.h.
14556 If the return value is based on the assumption that signed overflow
14557 is undefined, set *STRICT_OVERFLOW_P to true; otherwise, don't
14558 change *STRICT_OVERFLOW_P. */
14561 tree_single_nonzero_warnv_p (tree t, bool *strict_overflow_p)
14563 bool sub_strict_overflow_p;
14564 switch (TREE_CODE (t))
14567 /* Query VRP to see if it has recorded any information about
14568 the range of this object. */
14569 return ssa_name_nonzero_p (t);
14572 return !integer_zerop (t);
14576 tree base = get_base_address (TREE_OPERAND (t, 0));
14581 /* Weak declarations may link to NULL. */
14582 if (VAR_OR_FUNCTION_DECL_P (base))
14583 return !DECL_WEAK (base);
14585 /* Constants are never weak. */
14586 if (CONSTANT_CLASS_P (base))
14593 sub_strict_overflow_p = false;
14594 if (tree_expr_nonzero_warnv_p (TREE_OPERAND (t, 1),
14595 &sub_strict_overflow_p)
14596 && tree_expr_nonzero_warnv_p (TREE_OPERAND (t, 2),
14597 &sub_strict_overflow_p))
14599 if (sub_strict_overflow_p)
14600 *strict_overflow_p = true;
14611 /* Return true when T is an address and is known to be nonzero.
14612 For floating point we further ensure that T is not denormal.
14613 Similar logic is present in nonzero_address in rtlanal.h.
14615 If the return value is based on the assumption that signed overflow
14616 is undefined, set *STRICT_OVERFLOW_P to true; otherwise, don't
14617 change *STRICT_OVERFLOW_P. */
14620 tree_expr_nonzero_warnv_p (tree t, bool *strict_overflow_p)
14622 tree type = TREE_TYPE (t);
14623 enum tree_code code;
14625 /* Doing something useful for floating point would need more work. */
14626 if (!INTEGRAL_TYPE_P (type) && !POINTER_TYPE_P (type))
14629 code = TREE_CODE (t);
14630 switch (TREE_CODE_CLASS (code))
14633 return tree_unary_nonzero_warnv_p (code, type, TREE_OPERAND (t, 0),
14634 strict_overflow_p);
14636 case tcc_comparison:
14637 return tree_binary_nonzero_warnv_p (code, type,
14638 TREE_OPERAND (t, 0),
14639 TREE_OPERAND (t, 1),
14640 strict_overflow_p);
14642 case tcc_declaration:
14643 case tcc_reference:
14644 return tree_single_nonzero_warnv_p (t, strict_overflow_p);
14652 case TRUTH_NOT_EXPR:
14653 return tree_unary_nonzero_warnv_p (code, type, TREE_OPERAND (t, 0),
14654 strict_overflow_p);
14656 case TRUTH_AND_EXPR:
14657 case TRUTH_OR_EXPR:
14658 case TRUTH_XOR_EXPR:
14659 return tree_binary_nonzero_warnv_p (code, type,
14660 TREE_OPERAND (t, 0),
14661 TREE_OPERAND (t, 1),
14662 strict_overflow_p);
14669 case WITH_SIZE_EXPR:
14673 return tree_single_nonzero_warnv_p (t, strict_overflow_p);
14675 case COMPOUND_EXPR:
14677 case GIMPLE_MODIFY_STMT:
14679 return tree_expr_nonzero_warnv_p (GENERIC_TREE_OPERAND (t, 1),
14680 strict_overflow_p);
14683 return tree_expr_nonzero_warnv_p (TREE_OPERAND (t, 0),
14684 strict_overflow_p);
14687 return alloca_call_p (t);
14695 /* Return true when T is an address and is known to be nonzero.
14696 Handle warnings about undefined signed overflow. */
14699 tree_expr_nonzero_p (tree t)
14701 bool ret, strict_overflow_p;
14703 strict_overflow_p = false;
14704 ret = tree_expr_nonzero_warnv_p (t, &strict_overflow_p);
14705 if (strict_overflow_p)
14706 fold_overflow_warning (("assuming signed overflow does not occur when "
14707 "determining that expression is always "
14709 WARN_STRICT_OVERFLOW_MISC);
14713 /* Given the components of a binary expression CODE, TYPE, OP0 and OP1,
14714 attempt to fold the expression to a constant without modifying TYPE,
14717 If the expression could be simplified to a constant, then return
14718 the constant. If the expression would not be simplified to a
14719 constant, then return NULL_TREE. */
14722 fold_binary_to_constant (enum tree_code code, tree type, tree op0, tree op1)
14724 tree tem = fold_binary (code, type, op0, op1);
14725 return (tem && TREE_CONSTANT (tem)) ? tem : NULL_TREE;
14728 /* Given the components of a unary expression CODE, TYPE and OP0,
14729 attempt to fold the expression to a constant without modifying
14732 If the expression could be simplified to a constant, then return
14733 the constant. If the expression would not be simplified to a
14734 constant, then return NULL_TREE. */
14737 fold_unary_to_constant (enum tree_code code, tree type, tree op0)
14739 tree tem = fold_unary (code, type, op0);
14740 return (tem && TREE_CONSTANT (tem)) ? tem : NULL_TREE;
14743 /* If EXP represents referencing an element in a constant string
14744 (either via pointer arithmetic or array indexing), return the
14745 tree representing the value accessed, otherwise return NULL. */
14748 fold_read_from_constant_string (tree exp)
14750 if ((TREE_CODE (exp) == INDIRECT_REF
14751 || TREE_CODE (exp) == ARRAY_REF)
14752 && TREE_CODE (TREE_TYPE (exp)) == INTEGER_TYPE)
14754 tree exp1 = TREE_OPERAND (exp, 0);
14758 if (TREE_CODE (exp) == INDIRECT_REF)
14759 string = string_constant (exp1, &index);
14762 tree low_bound = array_ref_low_bound (exp);
14763 index = fold_convert (sizetype, TREE_OPERAND (exp, 1));
14765 /* Optimize the special-case of a zero lower bound.
14767 We convert the low_bound to sizetype to avoid some problems
14768 with constant folding. (E.g. suppose the lower bound is 1,
14769 and its mode is QI. Without the conversion,l (ARRAY
14770 +(INDEX-(unsigned char)1)) becomes ((ARRAY+(-(unsigned char)1))
14771 +INDEX), which becomes (ARRAY+255+INDEX). Opps!) */
14772 if (! integer_zerop (low_bound))
14773 index = size_diffop (index, fold_convert (sizetype, low_bound));
14779 && TYPE_MODE (TREE_TYPE (exp)) == TYPE_MODE (TREE_TYPE (TREE_TYPE (string)))
14780 && TREE_CODE (string) == STRING_CST
14781 && TREE_CODE (index) == INTEGER_CST
14782 && compare_tree_int (index, TREE_STRING_LENGTH (string)) < 0
14783 && (GET_MODE_CLASS (TYPE_MODE (TREE_TYPE (TREE_TYPE (string))))
14785 && (GET_MODE_SIZE (TYPE_MODE (TREE_TYPE (TREE_TYPE (string)))) == 1))
14786 return build_int_cst_type (TREE_TYPE (exp),
14787 (TREE_STRING_POINTER (string)
14788 [TREE_INT_CST_LOW (index)]));
14793 /* Return the tree for neg (ARG0) when ARG0 is known to be either
14794 an integer constant, real, or fixed-point constant.
14796 TYPE is the type of the result. */
14799 fold_negate_const (tree arg0, tree type)
14801 tree t = NULL_TREE;
14803 switch (TREE_CODE (arg0))
14807 unsigned HOST_WIDE_INT low;
14808 HOST_WIDE_INT high;
14809 int overflow = neg_double (TREE_INT_CST_LOW (arg0),
14810 TREE_INT_CST_HIGH (arg0),
14812 t = force_fit_type_double (type, low, high, 1,
14813 (overflow | TREE_OVERFLOW (arg0))
14814 && !TYPE_UNSIGNED (type));
14819 t = build_real (type, REAL_VALUE_NEGATE (TREE_REAL_CST (arg0)));
14824 FIXED_VALUE_TYPE f;
14825 bool overflow_p = fixed_arithmetic (&f, NEGATE_EXPR,
14826 &(TREE_FIXED_CST (arg0)), NULL,
14827 TYPE_SATURATING (type));
14828 t = build_fixed (type, f);
14829 /* Propagate overflow flags. */
14830 if (overflow_p | TREE_OVERFLOW (arg0))
14832 TREE_OVERFLOW (t) = 1;
14833 TREE_CONSTANT_OVERFLOW (t) = 1;
14835 else if (TREE_CONSTANT_OVERFLOW (arg0))
14836 TREE_CONSTANT_OVERFLOW (t) = 1;
14841 gcc_unreachable ();
14847 /* Return the tree for abs (ARG0) when ARG0 is known to be either
14848 an integer constant or real constant.
14850 TYPE is the type of the result. */
14853 fold_abs_const (tree arg0, tree type)
14855 tree t = NULL_TREE;
14857 switch (TREE_CODE (arg0))
14860 /* If the value is unsigned, then the absolute value is
14861 the same as the ordinary value. */
14862 if (TYPE_UNSIGNED (type))
14864 /* Similarly, if the value is non-negative. */
14865 else if (INT_CST_LT (integer_minus_one_node, arg0))
14867 /* If the value is negative, then the absolute value is
14871 unsigned HOST_WIDE_INT low;
14872 HOST_WIDE_INT high;
14873 int overflow = neg_double (TREE_INT_CST_LOW (arg0),
14874 TREE_INT_CST_HIGH (arg0),
14876 t = force_fit_type_double (type, low, high, -1,
14877 overflow | TREE_OVERFLOW (arg0));
14882 if (REAL_VALUE_NEGATIVE (TREE_REAL_CST (arg0)))
14883 t = build_real (type, REAL_VALUE_NEGATE (TREE_REAL_CST (arg0)));
14889 gcc_unreachable ();
14895 /* Return the tree for not (ARG0) when ARG0 is known to be an integer
14896 constant. TYPE is the type of the result. */
14899 fold_not_const (tree arg0, tree type)
14901 tree t = NULL_TREE;
14903 gcc_assert (TREE_CODE (arg0) == INTEGER_CST);
14905 t = force_fit_type_double (type, ~TREE_INT_CST_LOW (arg0),
14906 ~TREE_INT_CST_HIGH (arg0), 0,
14907 TREE_OVERFLOW (arg0));
14912 /* Given CODE, a relational operator, the target type, TYPE and two
14913 constant operands OP0 and OP1, return the result of the
14914 relational operation. If the result is not a compile time
14915 constant, then return NULL_TREE. */
14918 fold_relational_const (enum tree_code code, tree type, tree op0, tree op1)
14920 int result, invert;
14922 /* From here on, the only cases we handle are when the result is
14923 known to be a constant. */
14925 if (TREE_CODE (op0) == REAL_CST && TREE_CODE (op1) == REAL_CST)
14927 const REAL_VALUE_TYPE *c0 = TREE_REAL_CST_PTR (op0);
14928 const REAL_VALUE_TYPE *c1 = TREE_REAL_CST_PTR (op1);
14930 /* Handle the cases where either operand is a NaN. */
14931 if (real_isnan (c0) || real_isnan (c1))
14941 case UNORDERED_EXPR:
14955 if (flag_trapping_math)
14961 gcc_unreachable ();
14964 return constant_boolean_node (result, type);
14967 return constant_boolean_node (real_compare (code, c0, c1), type);
14970 if (TREE_CODE (op0) == FIXED_CST && TREE_CODE (op1) == FIXED_CST)
14972 const FIXED_VALUE_TYPE *c0 = TREE_FIXED_CST_PTR (op0);
14973 const FIXED_VALUE_TYPE *c1 = TREE_FIXED_CST_PTR (op1);
14974 return constant_boolean_node (fixed_compare (code, c0, c1), type);
14977 /* Handle equality/inequality of complex constants. */
14978 if (TREE_CODE (op0) == COMPLEX_CST && TREE_CODE (op1) == COMPLEX_CST)
14980 tree rcond = fold_relational_const (code, type,
14981 TREE_REALPART (op0),
14982 TREE_REALPART (op1));
14983 tree icond = fold_relational_const (code, type,
14984 TREE_IMAGPART (op0),
14985 TREE_IMAGPART (op1));
14986 if (code == EQ_EXPR)
14987 return fold_build2 (TRUTH_ANDIF_EXPR, type, rcond, icond);
14988 else if (code == NE_EXPR)
14989 return fold_build2 (TRUTH_ORIF_EXPR, type, rcond, icond);
14994 /* From here on we only handle LT, LE, GT, GE, EQ and NE.
14996 To compute GT, swap the arguments and do LT.
14997 To compute GE, do LT and invert the result.
14998 To compute LE, swap the arguments, do LT and invert the result.
14999 To compute NE, do EQ and invert the result.
15001 Therefore, the code below must handle only EQ and LT. */
15003 if (code == LE_EXPR || code == GT_EXPR)
15008 code = swap_tree_comparison (code);
15011 /* Note that it is safe to invert for real values here because we
15012 have already handled the one case that it matters. */
15015 if (code == NE_EXPR || code == GE_EXPR)
15018 code = invert_tree_comparison (code, false);
15021 /* Compute a result for LT or EQ if args permit;
15022 Otherwise return T. */
15023 if (TREE_CODE (op0) == INTEGER_CST && TREE_CODE (op1) == INTEGER_CST)
15025 if (code == EQ_EXPR)
15026 result = tree_int_cst_equal (op0, op1);
15027 else if (TYPE_UNSIGNED (TREE_TYPE (op0)))
15028 result = INT_CST_LT_UNSIGNED (op0, op1);
15030 result = INT_CST_LT (op0, op1);
15037 return constant_boolean_node (result, type);
15040 /* If necessary, return a CLEANUP_POINT_EXPR for EXPR with the
15041 indicated TYPE. If no CLEANUP_POINT_EXPR is necessary, return EXPR
15045 fold_build_cleanup_point_expr (tree type, tree expr)
15047 /* If the expression does not have side effects then we don't have to wrap
15048 it with a cleanup point expression. */
15049 if (!TREE_SIDE_EFFECTS (expr))
15052 /* If the expression is a return, check to see if the expression inside the
15053 return has no side effects or the right hand side of the modify expression
15054 inside the return. If either don't have side effects set we don't need to
15055 wrap the expression in a cleanup point expression. Note we don't check the
15056 left hand side of the modify because it should always be a return decl. */
15057 if (TREE_CODE (expr) == RETURN_EXPR)
15059 tree op = TREE_OPERAND (expr, 0);
15060 if (!op || !TREE_SIDE_EFFECTS (op))
15062 op = TREE_OPERAND (op, 1);
15063 if (!TREE_SIDE_EFFECTS (op))
15067 return build1 (CLEANUP_POINT_EXPR, type, expr);
15070 /* Given a pointer value OP0 and a type TYPE, return a simplified version
15071 of an indirection through OP0, or NULL_TREE if no simplification is
15075 fold_indirect_ref_1 (tree type, tree op0)
15081 subtype = TREE_TYPE (sub);
15082 if (!POINTER_TYPE_P (subtype))
15085 if (TREE_CODE (sub) == ADDR_EXPR)
15087 tree op = TREE_OPERAND (sub, 0);
15088 tree optype = TREE_TYPE (op);
15089 /* *&CONST_DECL -> to the value of the const decl. */
15090 if (TREE_CODE (op) == CONST_DECL)
15091 return DECL_INITIAL (op);
15092 /* *&p => p; make sure to handle *&"str"[cst] here. */
15093 if (type == optype)
15095 tree fop = fold_read_from_constant_string (op);
15101 /* *(foo *)&fooarray => fooarray[0] */
15102 else if (TREE_CODE (optype) == ARRAY_TYPE
15103 && type == TREE_TYPE (optype))
15105 tree type_domain = TYPE_DOMAIN (optype);
15106 tree min_val = size_zero_node;
15107 if (type_domain && TYPE_MIN_VALUE (type_domain))
15108 min_val = TYPE_MIN_VALUE (type_domain);
15109 return build4 (ARRAY_REF, type, op, min_val, NULL_TREE, NULL_TREE);
15111 /* *(foo *)&complexfoo => __real__ complexfoo */
15112 else if (TREE_CODE (optype) == COMPLEX_TYPE
15113 && type == TREE_TYPE (optype))
15114 return fold_build1 (REALPART_EXPR, type, op);
15115 /* *(foo *)&vectorfoo => BIT_FIELD_REF<vectorfoo,...> */
15116 else if (TREE_CODE (optype) == VECTOR_TYPE
15117 && type == TREE_TYPE (optype))
15119 tree part_width = TYPE_SIZE (type);
15120 tree index = bitsize_int (0);
15121 return fold_build3 (BIT_FIELD_REF, type, op, part_width, index);
15125 /* ((foo*)&vectorfoo)[1] => BIT_FIELD_REF<vectorfoo,...> */
15126 if (TREE_CODE (sub) == POINTER_PLUS_EXPR
15127 && TREE_CODE (TREE_OPERAND (sub, 1)) == INTEGER_CST)
15129 tree op00 = TREE_OPERAND (sub, 0);
15130 tree op01 = TREE_OPERAND (sub, 1);
15134 op00type = TREE_TYPE (op00);
15135 if (TREE_CODE (op00) == ADDR_EXPR
15136 && TREE_CODE (TREE_TYPE (op00type)) == VECTOR_TYPE
15137 && type == TREE_TYPE (TREE_TYPE (op00type)))
15139 HOST_WIDE_INT offset = tree_low_cst (op01, 0);
15140 tree part_width = TYPE_SIZE (type);
15141 unsigned HOST_WIDE_INT part_widthi = tree_low_cst (part_width, 0)/BITS_PER_UNIT;
15142 unsigned HOST_WIDE_INT indexi = offset * BITS_PER_UNIT;
15143 tree index = bitsize_int (indexi);
15145 if (offset/part_widthi <= TYPE_VECTOR_SUBPARTS (TREE_TYPE (op00type)))
15146 return fold_build3 (BIT_FIELD_REF, type, TREE_OPERAND (op00, 0),
15147 part_width, index);
15153 /* ((foo*)&complexfoo)[1] => __imag__ complexfoo */
15154 if (TREE_CODE (sub) == POINTER_PLUS_EXPR
15155 && TREE_CODE (TREE_OPERAND (sub, 1)) == INTEGER_CST)
15157 tree op00 = TREE_OPERAND (sub, 0);
15158 tree op01 = TREE_OPERAND (sub, 1);
15162 op00type = TREE_TYPE (op00);
15163 if (TREE_CODE (op00) == ADDR_EXPR
15164 && TREE_CODE (TREE_TYPE (op00type)) == COMPLEX_TYPE
15165 && type == TREE_TYPE (TREE_TYPE (op00type)))
15167 tree size = TYPE_SIZE_UNIT (type);
15168 if (tree_int_cst_equal (size, op01))
15169 return fold_build1 (IMAGPART_EXPR, type, TREE_OPERAND (op00, 0));
15173 /* *(foo *)fooarrptr => (*fooarrptr)[0] */
15174 if (TREE_CODE (TREE_TYPE (subtype)) == ARRAY_TYPE
15175 && type == TREE_TYPE (TREE_TYPE (subtype)))
15178 tree min_val = size_zero_node;
15179 sub = build_fold_indirect_ref (sub);
15180 type_domain = TYPE_DOMAIN (TREE_TYPE (sub));
15181 if (type_domain && TYPE_MIN_VALUE (type_domain))
15182 min_val = TYPE_MIN_VALUE (type_domain);
15183 return build4 (ARRAY_REF, type, sub, min_val, NULL_TREE, NULL_TREE);
15189 /* Builds an expression for an indirection through T, simplifying some
15193 build_fold_indirect_ref (tree t)
15195 tree type = TREE_TYPE (TREE_TYPE (t));
15196 tree sub = fold_indirect_ref_1 (type, t);
15201 return build1 (INDIRECT_REF, type, t);
15204 /* Given an INDIRECT_REF T, return either T or a simplified version. */
15207 fold_indirect_ref (tree t)
15209 tree sub = fold_indirect_ref_1 (TREE_TYPE (t), TREE_OPERAND (t, 0));
15217 /* Strip non-trapping, non-side-effecting tree nodes from an expression
15218 whose result is ignored. The type of the returned tree need not be
15219 the same as the original expression. */
15222 fold_ignored_result (tree t)
15224 if (!TREE_SIDE_EFFECTS (t))
15225 return integer_zero_node;
15228 switch (TREE_CODE_CLASS (TREE_CODE (t)))
15231 t = TREE_OPERAND (t, 0);
15235 case tcc_comparison:
15236 if (!TREE_SIDE_EFFECTS (TREE_OPERAND (t, 1)))
15237 t = TREE_OPERAND (t, 0);
15238 else if (!TREE_SIDE_EFFECTS (TREE_OPERAND (t, 0)))
15239 t = TREE_OPERAND (t, 1);
15244 case tcc_expression:
15245 switch (TREE_CODE (t))
15247 case COMPOUND_EXPR:
15248 if (TREE_SIDE_EFFECTS (TREE_OPERAND (t, 1)))
15250 t = TREE_OPERAND (t, 0);
15254 if (TREE_SIDE_EFFECTS (TREE_OPERAND (t, 1))
15255 || TREE_SIDE_EFFECTS (TREE_OPERAND (t, 2)))
15257 t = TREE_OPERAND (t, 0);
15270 /* Return the value of VALUE, rounded up to a multiple of DIVISOR.
15271 This can only be applied to objects of a sizetype. */
15274 round_up (tree value, int divisor)
15276 tree div = NULL_TREE;
15278 gcc_assert (divisor > 0);
15282 /* See if VALUE is already a multiple of DIVISOR. If so, we don't
15283 have to do anything. Only do this when we are not given a const,
15284 because in that case, this check is more expensive than just
15286 if (TREE_CODE (value) != INTEGER_CST)
15288 div = build_int_cst (TREE_TYPE (value), divisor);
15290 if (multiple_of_p (TREE_TYPE (value), value, div))
15294 /* If divisor is a power of two, simplify this to bit manipulation. */
15295 if (divisor == (divisor & -divisor))
15297 if (TREE_CODE (value) == INTEGER_CST)
15299 unsigned HOST_WIDE_INT low = TREE_INT_CST_LOW (value);
15300 unsigned HOST_WIDE_INT high;
15303 if ((low & (divisor - 1)) == 0)
15306 overflow_p = TREE_OVERFLOW (value);
15307 high = TREE_INT_CST_HIGH (value);
15308 low &= ~(divisor - 1);
15317 return force_fit_type_double (TREE_TYPE (value), low, high,
15324 t = build_int_cst (TREE_TYPE (value), divisor - 1);
15325 value = size_binop (PLUS_EXPR, value, t);
15326 t = build_int_cst (TREE_TYPE (value), -divisor);
15327 value = size_binop (BIT_AND_EXPR, value, t);
15333 div = build_int_cst (TREE_TYPE (value), divisor);
15334 value = size_binop (CEIL_DIV_EXPR, value, div);
15335 value = size_binop (MULT_EXPR, value, div);
15341 /* Likewise, but round down. */
15344 round_down (tree value, int divisor)
15346 tree div = NULL_TREE;
15348 gcc_assert (divisor > 0);
15352 /* See if VALUE is already a multiple of DIVISOR. If so, we don't
15353 have to do anything. Only do this when we are not given a const,
15354 because in that case, this check is more expensive than just
15356 if (TREE_CODE (value) != INTEGER_CST)
15358 div = build_int_cst (TREE_TYPE (value), divisor);
15360 if (multiple_of_p (TREE_TYPE (value), value, div))
15364 /* If divisor is a power of two, simplify this to bit manipulation. */
15365 if (divisor == (divisor & -divisor))
15369 t = build_int_cst (TREE_TYPE (value), -divisor);
15370 value = size_binop (BIT_AND_EXPR, value, t);
15375 div = build_int_cst (TREE_TYPE (value), divisor);
15376 value = size_binop (FLOOR_DIV_EXPR, value, div);
15377 value = size_binop (MULT_EXPR, value, div);
15383 /* Returns the pointer to the base of the object addressed by EXP and
15384 extracts the information about the offset of the access, storing it
15385 to PBITPOS and POFFSET. */
15388 split_address_to_core_and_offset (tree exp,
15389 HOST_WIDE_INT *pbitpos, tree *poffset)
15392 enum machine_mode mode;
15393 int unsignedp, volatilep;
15394 HOST_WIDE_INT bitsize;
15396 if (TREE_CODE (exp) == ADDR_EXPR)
15398 core = get_inner_reference (TREE_OPERAND (exp, 0), &bitsize, pbitpos,
15399 poffset, &mode, &unsignedp, &volatilep,
15401 core = fold_addr_expr (core);
15407 *poffset = NULL_TREE;
15413 /* Returns true if addresses of E1 and E2 differ by a constant, false
15414 otherwise. If they do, E1 - E2 is stored in *DIFF. */
15417 ptr_difference_const (tree e1, tree e2, HOST_WIDE_INT *diff)
15420 HOST_WIDE_INT bitpos1, bitpos2;
15421 tree toffset1, toffset2, tdiff, type;
15423 core1 = split_address_to_core_and_offset (e1, &bitpos1, &toffset1);
15424 core2 = split_address_to_core_and_offset (e2, &bitpos2, &toffset2);
15426 if (bitpos1 % BITS_PER_UNIT != 0
15427 || bitpos2 % BITS_PER_UNIT != 0
15428 || !operand_equal_p (core1, core2, 0))
15431 if (toffset1 && toffset2)
15433 type = TREE_TYPE (toffset1);
15434 if (type != TREE_TYPE (toffset2))
15435 toffset2 = fold_convert (type, toffset2);
15437 tdiff = fold_build2 (MINUS_EXPR, type, toffset1, toffset2);
15438 if (!cst_and_fits_in_hwi (tdiff))
15441 *diff = int_cst_value (tdiff);
15443 else if (toffset1 || toffset2)
15445 /* If only one of the offsets is non-constant, the difference cannot
15452 *diff += (bitpos1 - bitpos2) / BITS_PER_UNIT;
15456 /* Simplify the floating point expression EXP when the sign of the
15457 result is not significant. Return NULL_TREE if no simplification
15461 fold_strip_sign_ops (tree exp)
15465 switch (TREE_CODE (exp))
15469 arg0 = fold_strip_sign_ops (TREE_OPERAND (exp, 0));
15470 return arg0 ? arg0 : TREE_OPERAND (exp, 0);
15474 if (HONOR_SIGN_DEPENDENT_ROUNDING (TYPE_MODE (TREE_TYPE (exp))))
15476 arg0 = fold_strip_sign_ops (TREE_OPERAND (exp, 0));
15477 arg1 = fold_strip_sign_ops (TREE_OPERAND (exp, 1));
15478 if (arg0 != NULL_TREE || arg1 != NULL_TREE)
15479 return fold_build2 (TREE_CODE (exp), TREE_TYPE (exp),
15480 arg0 ? arg0 : TREE_OPERAND (exp, 0),
15481 arg1 ? arg1 : TREE_OPERAND (exp, 1));
15484 case COMPOUND_EXPR:
15485 arg0 = TREE_OPERAND (exp, 0);
15486 arg1 = fold_strip_sign_ops (TREE_OPERAND (exp, 1));
15488 return fold_build2 (COMPOUND_EXPR, TREE_TYPE (exp), arg0, arg1);
15492 arg0 = fold_strip_sign_ops (TREE_OPERAND (exp, 1));
15493 arg1 = fold_strip_sign_ops (TREE_OPERAND (exp, 2));
15495 return fold_build3 (COND_EXPR, TREE_TYPE (exp), TREE_OPERAND (exp, 0),
15496 arg0 ? arg0 : TREE_OPERAND (exp, 1),
15497 arg1 ? arg1 : TREE_OPERAND (exp, 2));
15502 const enum built_in_function fcode = builtin_mathfn_code (exp);
15505 CASE_FLT_FN (BUILT_IN_COPYSIGN):
15506 /* Strip copysign function call, return the 1st argument. */
15507 arg0 = CALL_EXPR_ARG (exp, 0);
15508 arg1 = CALL_EXPR_ARG (exp, 1);
15509 return omit_one_operand (TREE_TYPE (exp), arg0, arg1);
15512 /* Strip sign ops from the argument of "odd" math functions. */
15513 if (negate_mathfn_p (fcode))
15515 arg0 = fold_strip_sign_ops (CALL_EXPR_ARG (exp, 0));
15517 return build_call_expr (get_callee_fndecl (exp), 1, arg0);