re PR middle-end/25529 ((unsigned * 2)/2 is not changed into unsigned &0x7FFFFFFF)
[gcc.git] / gcc / match.pd
1 /* Match-and-simplify patterns for shared GENERIC and GIMPLE folding.
2 This file is consumed by genmatch which produces gimple-match.c
3 and generic-match.c from it.
4
5 Copyright (C) 2014-2015 Free Software Foundation, Inc.
6 Contributed by Richard Biener <rguenther@suse.de>
7 and Prathamesh Kulkarni <bilbotheelffriend@gmail.com>
8
9 This file is part of GCC.
10
11 GCC is free software; you can redistribute it and/or modify it under
12 the terms of the GNU General Public License as published by the Free
13 Software Foundation; either version 3, or (at your option) any later
14 version.
15
16 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
17 WARRANTY; without even the implied warranty of MERCHANTABILITY or
18 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
19 for more details.
20
21 You should have received a copy of the GNU General Public License
22 along with GCC; see the file COPYING3. If not see
23 <http://www.gnu.org/licenses/>. */
24
25
26 /* Generic tree predicates we inherit. */
27 (define_predicates
28 integer_onep integer_zerop integer_all_onesp integer_minus_onep
29 integer_each_onep integer_truep integer_nonzerop
30 real_zerop real_onep real_minus_onep
31 CONSTANT_CLASS_P
32 tree_expr_nonnegative_p
33 integer_pow2p
34 HONOR_NANS)
35
36 /* Operator lists. */
37 (define_operator_list tcc_comparison
38 lt le eq ne ge gt unordered ordered unlt unle ungt unge uneq ltgt)
39 (define_operator_list inverted_tcc_comparison
40 ge gt ne eq lt le ordered unordered ge gt le lt ltgt uneq)
41 (define_operator_list inverted_tcc_comparison_with_nans
42 unge ungt ne eq unlt unle ordered unordered ge gt le lt ltgt uneq)
43 (define_operator_list swapped_tcc_comparison
44 gt ge eq ne le lt unordered ordered ungt unge unlt unle uneq ltgt)
45 (define_operator_list simple_comparison lt le eq ne ge gt)
46 (define_operator_list swapped_simple_comparison gt ge eq ne le lt)
47
48 (define_operator_list LOG BUILT_IN_LOGF BUILT_IN_LOG BUILT_IN_LOGL)
49 (define_operator_list EXP BUILT_IN_EXPF BUILT_IN_EXP BUILT_IN_EXPL)
50 (define_operator_list LOG2 BUILT_IN_LOG2F BUILT_IN_LOG2 BUILT_IN_LOG2L)
51 (define_operator_list EXP2 BUILT_IN_EXP2F BUILT_IN_EXP2 BUILT_IN_EXP2L)
52 (define_operator_list LOG10 BUILT_IN_LOG10F BUILT_IN_LOG10 BUILT_IN_LOG10L)
53 (define_operator_list EXP10 BUILT_IN_EXP10F BUILT_IN_EXP10 BUILT_IN_EXP10L)
54 (define_operator_list POW BUILT_IN_POWF BUILT_IN_POW BUILT_IN_POWL)
55 (define_operator_list POW10 BUILT_IN_POW10F BUILT_IN_POW10 BUILT_IN_POW10L)
56 (define_operator_list SQRT BUILT_IN_SQRTF BUILT_IN_SQRT BUILT_IN_SQRTL)
57 (define_operator_list CBRT BUILT_IN_CBRTF BUILT_IN_CBRT BUILT_IN_CBRTL)
58
59
60 /* Simplifications of operations with one constant operand and
61 simplifications to constants or single values. */
62
63 (for op (plus pointer_plus minus bit_ior bit_xor)
64 (simplify
65 (op @0 integer_zerop)
66 (non_lvalue @0)))
67
68 /* 0 +p index -> (type)index */
69 (simplify
70 (pointer_plus integer_zerop @1)
71 (non_lvalue (convert @1)))
72
73 /* See if ARG1 is zero and X + ARG1 reduces to X.
74 Likewise if the operands are reversed. */
75 (simplify
76 (plus:c @0 real_zerop@1)
77 (if (fold_real_zero_addition_p (type, @1, 0))
78 (non_lvalue @0)))
79
80 /* See if ARG1 is zero and X - ARG1 reduces to X. */
81 (simplify
82 (minus @0 real_zerop@1)
83 (if (fold_real_zero_addition_p (type, @1, 1))
84 (non_lvalue @0)))
85
86 /* Simplify x - x.
87 This is unsafe for certain floats even in non-IEEE formats.
88 In IEEE, it is unsafe because it does wrong for NaNs.
89 Also note that operand_equal_p is always false if an operand
90 is volatile. */
91 (simplify
92 (minus @0 @0)
93 (if (!FLOAT_TYPE_P (type) || !HONOR_NANS (type))
94 { build_zero_cst (type); }))
95
96 (simplify
97 (mult @0 integer_zerop@1)
98 @1)
99
100 /* Maybe fold x * 0 to 0. The expressions aren't the same
101 when x is NaN, since x * 0 is also NaN. Nor are they the
102 same in modes with signed zeros, since multiplying a
103 negative value by 0 gives -0, not +0. */
104 (simplify
105 (mult @0 real_zerop@1)
106 (if (!HONOR_NANS (type) && !HONOR_SIGNED_ZEROS (type))
107 @1))
108
109 /* In IEEE floating point, x*1 is not equivalent to x for snans.
110 Likewise for complex arithmetic with signed zeros. */
111 (simplify
112 (mult @0 real_onep)
113 (if (!HONOR_SNANS (type)
114 && (!HONOR_SIGNED_ZEROS (type)
115 || !COMPLEX_FLOAT_TYPE_P (type)))
116 (non_lvalue @0)))
117
118 /* Transform x * -1.0 into -x. */
119 (simplify
120 (mult @0 real_minus_onep)
121 (if (!HONOR_SNANS (type)
122 && (!HONOR_SIGNED_ZEROS (type)
123 || !COMPLEX_FLOAT_TYPE_P (type)))
124 (negate @0)))
125
126 /* Make sure to preserve divisions by zero. This is the reason why
127 we don't simplify x / x to 1 or 0 / x to 0. */
128 (for op (mult trunc_div ceil_div floor_div round_div exact_div)
129 (simplify
130 (op @0 integer_onep)
131 (non_lvalue @0)))
132
133 /* X / -1 is -X. */
134 (for div (trunc_div ceil_div floor_div round_div exact_div)
135 (simplify
136 (div @0 integer_minus_onep@1)
137 (if (!TYPE_UNSIGNED (type))
138 (negate @0))))
139
140 /* For unsigned integral types, FLOOR_DIV_EXPR is the same as
141 TRUNC_DIV_EXPR. Rewrite into the latter in this case. */
142 (simplify
143 (floor_div @0 @1)
144 (if ((INTEGRAL_TYPE_P (type) || VECTOR_INTEGER_TYPE_P (type))
145 && TYPE_UNSIGNED (type))
146 (trunc_div @0 @1)))
147
148 /* Combine two successive divisions. Note that combining ceil_div
149 and floor_div is trickier and combining round_div even more so. */
150 (for div (trunc_div exact_div)
151 (simplify
152 (div (div @0 INTEGER_CST@1) INTEGER_CST@2)
153 (with {
154 bool overflow_p;
155 wide_int mul = wi::mul (@1, @2, TYPE_SIGN (type), &overflow_p);
156 }
157 (if (!overflow_p)
158 (div @0 { wide_int_to_tree (type, mul); })
159 (if (TYPE_UNSIGNED (type)
160 || mul != wi::min_value (TYPE_PRECISION (type), SIGNED))
161 { build_zero_cst (type); })))))
162
163 /* Optimize A / A to 1.0 if we don't care about
164 NaNs or Infinities. */
165 (simplify
166 (rdiv @0 @0)
167 (if (FLOAT_TYPE_P (type)
168 && ! HONOR_NANS (type)
169 && ! HONOR_INFINITIES (type))
170 { build_one_cst (type); }))
171
172 /* Optimize -A / A to -1.0 if we don't care about
173 NaNs or Infinities. */
174 (simplify
175 (rdiv:c @0 (negate @0))
176 (if (FLOAT_TYPE_P (type)
177 && ! HONOR_NANS (type)
178 && ! HONOR_INFINITIES (type))
179 { build_minus_one_cst (type); }))
180
181 /* In IEEE floating point, x/1 is not equivalent to x for snans. */
182 (simplify
183 (rdiv @0 real_onep)
184 (if (!HONOR_SNANS (type))
185 (non_lvalue @0)))
186
187 /* In IEEE floating point, x/-1 is not equivalent to -x for snans. */
188 (simplify
189 (rdiv @0 real_minus_onep)
190 (if (!HONOR_SNANS (type))
191 (negate @0)))
192
193 /* If ARG1 is a constant, we can convert this to a multiply by the
194 reciprocal. This does not have the same rounding properties,
195 so only do this if -freciprocal-math. We can actually
196 always safely do it if ARG1 is a power of two, but it's hard to
197 tell if it is or not in a portable manner. */
198 (for cst (REAL_CST COMPLEX_CST VECTOR_CST)
199 (simplify
200 (rdiv @0 cst@1)
201 (if (optimize)
202 (if (flag_reciprocal_math
203 && !real_zerop (@1))
204 (with
205 { tree tem = const_binop (RDIV_EXPR, type, build_one_cst (type), @1); }
206 (if (tem)
207 (mult @0 { tem; } )))
208 (if (cst != COMPLEX_CST)
209 (with { tree inverse = exact_inverse (type, @1); }
210 (if (inverse)
211 (mult @0 { inverse; } ))))))))
212
213 /* Same applies to modulo operations, but fold is inconsistent here
214 and simplifies 0 % x to 0, only preserving literal 0 % 0. */
215 (for mod (ceil_mod floor_mod round_mod trunc_mod)
216 /* 0 % X is always zero. */
217 (simplify
218 (mod integer_zerop@0 @1)
219 /* But not for 0 % 0 so that we can get the proper warnings and errors. */
220 (if (!integer_zerop (@1))
221 @0))
222 /* X % 1 is always zero. */
223 (simplify
224 (mod @0 integer_onep)
225 { build_zero_cst (type); })
226 /* X % -1 is zero. */
227 (simplify
228 (mod @0 integer_minus_onep@1)
229 (if (!TYPE_UNSIGNED (type))
230 { build_zero_cst (type); }))
231 /* (X % Y) % Y is just X % Y. */
232 (simplify
233 (mod (mod@2 @0 @1) @1)
234 @2)
235 /* From extract_muldiv_1: (X * C1) % C2 is zero if C1 is a multiple of C2. */
236 (simplify
237 (mod (mult @0 INTEGER_CST@1) INTEGER_CST@2)
238 (if (ANY_INTEGRAL_TYPE_P (type)
239 && TYPE_OVERFLOW_UNDEFINED (type)
240 && wi::multiple_of_p (@1, @2, TYPE_SIGN (type)))
241 { build_zero_cst (type); })))
242
243 /* X % -C is the same as X % C. */
244 (simplify
245 (trunc_mod @0 INTEGER_CST@1)
246 (if (TYPE_SIGN (type) == SIGNED
247 && !TREE_OVERFLOW (@1)
248 && wi::neg_p (@1)
249 && !TYPE_OVERFLOW_TRAPS (type)
250 /* Avoid this transformation if C is INT_MIN, i.e. C == -C. */
251 && !sign_bit_p (@1, @1))
252 (trunc_mod @0 (negate @1))))
253
254 /* X % -Y is the same as X % Y. */
255 (simplify
256 (trunc_mod @0 (convert? (negate @1)))
257 (if (!TYPE_UNSIGNED (type)
258 && !TYPE_OVERFLOW_TRAPS (type)
259 && tree_nop_conversion_p (type, TREE_TYPE (@1)))
260 (trunc_mod @0 (convert @1))))
261
262 /* X - (X / Y) * Y is the same as X % Y. */
263 (simplify
264 (minus (convert1? @0) (convert2? (mult (trunc_div @0 @1) @1)))
265 (if (INTEGRAL_TYPE_P (type) || VECTOR_INTEGER_TYPE_P (type))
266 (trunc_mod (convert @0) (convert @1))))
267
268 /* Optimize TRUNC_MOD_EXPR by a power of two into a BIT_AND_EXPR,
269 i.e. "X % C" into "X & (C - 1)", if X and C are positive.
270 Also optimize A % (C << N) where C is a power of 2,
271 to A & ((C << N) - 1). */
272 (match (power_of_two_cand @1)
273 INTEGER_CST@1)
274 (match (power_of_two_cand @1)
275 (lshift INTEGER_CST@1 @2))
276 (for mod (trunc_mod floor_mod)
277 (simplify
278 (mod @0 (convert?@3 (power_of_two_cand@1 @2)))
279 (if ((TYPE_UNSIGNED (type)
280 || tree_expr_nonnegative_p (@0))
281 && tree_nop_conversion_p (type, TREE_TYPE (@3))
282 && integer_pow2p (@2) && tree_int_cst_sgn (@2) > 0)
283 (bit_and @0 (convert (minus @1 { build_int_cst (TREE_TYPE (@1), 1); }))))))
284
285 /* Simplify (unsigned t * 2)/2 -> unsigned t & 0x7FFFFFFF. */
286 (simplify
287 (trunc_div (mult @0 integer_pow2p@1) @1)
288 (if (TYPE_UNSIGNED (TREE_TYPE (@0)))
289 (bit_and @0 { wide_int_to_tree
290 (type, wi::mask (TYPE_PRECISION (type) - wi::exact_log2 (@1),
291 false, TYPE_PRECISION (type))); })))
292
293 /* Simplify (unsigned t / 2) * 2 -> unsigned t & ~1. */
294 (simplify
295 (mult (trunc_div @0 integer_pow2p@1) @1)
296 (if (TYPE_UNSIGNED (TREE_TYPE (@0)))
297 (bit_and @0 (negate @1))))
298
299 /* Simplify (t * 2) / 2) -> t. */
300 (for div (trunc_div ceil_div floor_div round_div exact_div)
301 (simplify
302 (div (mult @0 @1) @1)
303 (if (ANY_INTEGRAL_TYPE_P (type)
304 && TYPE_OVERFLOW_UNDEFINED (type))
305 @0)))
306
307 /* X % Y is smaller than Y. */
308 (for cmp (lt ge)
309 (simplify
310 (cmp (trunc_mod @0 @1) @1)
311 (if (TYPE_UNSIGNED (TREE_TYPE (@0)))
312 { constant_boolean_node (cmp == LT_EXPR, type); })))
313 (for cmp (gt le)
314 (simplify
315 (cmp @1 (trunc_mod @0 @1))
316 (if (TYPE_UNSIGNED (TREE_TYPE (@0)))
317 { constant_boolean_node (cmp == GT_EXPR, type); })))
318
319 /* x | ~0 -> ~0 */
320 (simplify
321 (bit_ior @0 integer_all_onesp@1)
322 @1)
323
324 /* x & 0 -> 0 */
325 (simplify
326 (bit_and @0 integer_zerop@1)
327 @1)
328
329 /* ~x | x -> -1 */
330 /* ~x ^ x -> -1 */
331 /* ~x + x -> -1 */
332 (for op (bit_ior bit_xor plus)
333 (simplify
334 (op:c (convert? @0) (convert? (bit_not @0)))
335 (convert { build_all_ones_cst (TREE_TYPE (@0)); })))
336
337 /* x ^ x -> 0 */
338 (simplify
339 (bit_xor @0 @0)
340 { build_zero_cst (type); })
341
342 /* Canonicalize X ^ ~0 to ~X. */
343 (simplify
344 (bit_xor @0 integer_all_onesp@1)
345 (bit_not @0))
346
347 /* x & ~0 -> x */
348 (simplify
349 (bit_and @0 integer_all_onesp)
350 (non_lvalue @0))
351
352 /* x & x -> x, x | x -> x */
353 (for bitop (bit_and bit_ior)
354 (simplify
355 (bitop @0 @0)
356 (non_lvalue @0)))
357
358 /* x + (x & 1) -> (x + 1) & ~1 */
359 (simplify
360 (plus:c @0 (bit_and:s @0 integer_onep@1))
361 (bit_and (plus @0 @1) (bit_not @1)))
362
363 /* x & ~(x & y) -> x & ~y */
364 /* x | ~(x | y) -> x | ~y */
365 (for bitop (bit_and bit_ior)
366 (simplify
367 (bitop:c @0 (bit_not (bitop:cs @0 @1)))
368 (bitop @0 (bit_not @1))))
369
370 /* (x | y) & ~x -> y & ~x */
371 /* (x & y) | ~x -> y | ~x */
372 (for bitop (bit_and bit_ior)
373 rbitop (bit_ior bit_and)
374 (simplify
375 (bitop:c (rbitop:c @0 @1) (bit_not@2 @0))
376 (bitop @1 @2)))
377
378 /* (x & y) ^ (x | y) -> x ^ y */
379 (simplify
380 (bit_xor:c (bit_and @0 @1) (bit_ior @0 @1))
381 (bit_xor @0 @1))
382
383 /* (x ^ y) ^ (x | y) -> x & y */
384 (simplify
385 (bit_xor:c (bit_xor @0 @1) (bit_ior @0 @1))
386 (bit_and @0 @1))
387
388 /* (x & y) + (x ^ y) -> x | y */
389 /* (x & y) | (x ^ y) -> x | y */
390 /* (x & y) ^ (x ^ y) -> x | y */
391 (for op (plus bit_ior bit_xor)
392 (simplify
393 (op:c (bit_and @0 @1) (bit_xor @0 @1))
394 (bit_ior @0 @1)))
395
396 /* (x & y) + (x | y) -> x + y */
397 (simplify
398 (plus:c (bit_and @0 @1) (bit_ior @0 @1))
399 (plus @0 @1))
400
401 /* (x + y) - (x | y) -> x & y */
402 (simplify
403 (minus (plus @0 @1) (bit_ior @0 @1))
404 (if (!TYPE_OVERFLOW_SANITIZED (type) && !TYPE_OVERFLOW_TRAPS (type)
405 && !TYPE_SATURATING (type))
406 (bit_and @0 @1)))
407
408 /* (x + y) - (x & y) -> x | y */
409 (simplify
410 (minus (plus @0 @1) (bit_and @0 @1))
411 (if (!TYPE_OVERFLOW_SANITIZED (type) && !TYPE_OVERFLOW_TRAPS (type)
412 && !TYPE_SATURATING (type))
413 (bit_ior @0 @1)))
414
415 /* (x | y) - (x ^ y) -> x & y */
416 (simplify
417 (minus (bit_ior @0 @1) (bit_xor @0 @1))
418 (bit_and @0 @1))
419
420 /* (x | y) - (x & y) -> x ^ y */
421 (simplify
422 (minus (bit_ior @0 @1) (bit_and @0 @1))
423 (bit_xor @0 @1))
424
425 /* (x | y) & ~(x & y) -> x ^ y */
426 (simplify
427 (bit_and:c (bit_ior @0 @1) (bit_not (bit_and @0 @1)))
428 (bit_xor @0 @1))
429
430 /* (x | y) & (~x ^ y) -> x & y */
431 (simplify
432 (bit_and:c (bit_ior:c @0 @1) (bit_xor:c @1 (bit_not @0)))
433 (bit_and @0 @1))
434
435 /* ~x & ~y -> ~(x | y)
436 ~x | ~y -> ~(x & y) */
437 (for op (bit_and bit_ior)
438 rop (bit_ior bit_and)
439 (simplify
440 (op (convert1? (bit_not @0)) (convert2? (bit_not @1)))
441 (if (tree_nop_conversion_p (type, TREE_TYPE (@0))
442 && tree_nop_conversion_p (type, TREE_TYPE (@1)))
443 (bit_not (rop (convert @0) (convert @1))))))
444
445 /* If we are XORing or adding two BIT_AND_EXPR's, both of which are and'ing
446 with a constant, and the two constants have no bits in common,
447 we should treat this as a BIT_IOR_EXPR since this may produce more
448 simplifications. */
449 (for op (bit_xor plus)
450 (simplify
451 (op (convert1? (bit_and@4 @0 INTEGER_CST@1))
452 (convert2? (bit_and@5 @2 INTEGER_CST@3)))
453 (if (tree_nop_conversion_p (type, TREE_TYPE (@0))
454 && tree_nop_conversion_p (type, TREE_TYPE (@2))
455 && wi::bit_and (@1, @3) == 0)
456 (bit_ior (convert @4) (convert @5)))))
457
458 /* (X | Y) ^ X -> Y & ~ X*/
459 (simplify
460 (bit_xor:c (convert? (bit_ior:c @0 @1)) (convert? @0))
461 (if (tree_nop_conversion_p (type, TREE_TYPE (@0)))
462 (convert (bit_and @1 (bit_not @0)))))
463
464 /* Convert ~X ^ ~Y to X ^ Y. */
465 (simplify
466 (bit_xor (convert1? (bit_not @0)) (convert2? (bit_not @1)))
467 (if (tree_nop_conversion_p (type, TREE_TYPE (@0))
468 && tree_nop_conversion_p (type, TREE_TYPE (@1)))
469 (bit_xor (convert @0) (convert @1))))
470
471 /* Convert ~X ^ C to X ^ ~C. */
472 (simplify
473 (bit_xor (convert? (bit_not @0)) INTEGER_CST@1)
474 (if (tree_nop_conversion_p (type, TREE_TYPE (@0)))
475 (bit_xor (convert @0) (bit_not @1))))
476
477 /* Fold (X & Y) ^ Y as ~X & Y. */
478 (simplify
479 (bit_xor:c (bit_and:c @0 @1) @1)
480 (bit_and (bit_not @0) @1))
481
482 /* Given a bit-wise operation CODE applied to ARG0 and ARG1, see if both
483 operands are another bit-wise operation with a common input. If so,
484 distribute the bit operations to save an operation and possibly two if
485 constants are involved. For example, convert
486 (A | B) & (A | C) into A | (B & C)
487 Further simplification will occur if B and C are constants. */
488 (for op (bit_and bit_ior)
489 rop (bit_ior bit_and)
490 (simplify
491 (op (convert? (rop:c @0 @1)) (convert? (rop @0 @2)))
492 (if (tree_nop_conversion_p (type, TREE_TYPE (@0)))
493 (rop (convert @0) (op (convert @1) (convert @2))))))
494
495
496 (simplify
497 (abs (abs@1 @0))
498 @1)
499 (simplify
500 (abs (negate @0))
501 (abs @0))
502 (simplify
503 (abs tree_expr_nonnegative_p@0)
504 @0)
505
506 /* A few cases of fold-const.c negate_expr_p predicate. */
507 (match negate_expr_p
508 INTEGER_CST
509 (if ((INTEGRAL_TYPE_P (type)
510 && TYPE_OVERFLOW_WRAPS (type))
511 || (!TYPE_OVERFLOW_SANITIZED (type)
512 && may_negate_without_overflow_p (t)))))
513 (match negate_expr_p
514 FIXED_CST)
515 (match negate_expr_p
516 (negate @0)
517 (if (!TYPE_OVERFLOW_SANITIZED (type))))
518 (match negate_expr_p
519 REAL_CST
520 (if (REAL_VALUE_NEGATIVE (TREE_REAL_CST (t)))))
521 /* VECTOR_CST handling of non-wrapping types would recurse in unsupported
522 ways. */
523 (match negate_expr_p
524 VECTOR_CST
525 (if (FLOAT_TYPE_P (TREE_TYPE (type)) || TYPE_OVERFLOW_WRAPS (type))))
526
527 /* -(A + B) -> (-B) - A. */
528 (simplify
529 (negate (plus:c @0 negate_expr_p@1))
530 (if (!HONOR_SIGN_DEPENDENT_ROUNDING (element_mode (type))
531 && !HONOR_SIGNED_ZEROS (element_mode (type)))
532 (minus (negate @1) @0)))
533
534 /* A - B -> A + (-B) if B is easily negatable. */
535 (simplify
536 (minus @0 negate_expr_p@1)
537 (if (!FIXED_POINT_TYPE_P (type))
538 (plus @0 (negate @1))))
539
540 /* Try to fold (type) X op CST -> (type) (X op ((type-x) CST))
541 when profitable.
542 For bitwise binary operations apply operand conversions to the
543 binary operation result instead of to the operands. This allows
544 to combine successive conversions and bitwise binary operations.
545 We combine the above two cases by using a conditional convert. */
546 (for bitop (bit_and bit_ior bit_xor)
547 (simplify
548 (bitop (convert @0) (convert? @1))
549 (if (((TREE_CODE (@1) == INTEGER_CST
550 && INTEGRAL_TYPE_P (TREE_TYPE (@0))
551 && int_fits_type_p (@1, TREE_TYPE (@0)))
552 || types_match (@0, @1))
553 /* ??? This transform conflicts with fold-const.c doing
554 Convert (T)(x & c) into (T)x & (T)c, if c is an integer
555 constants (if x has signed type, the sign bit cannot be set
556 in c). This folds extension into the BIT_AND_EXPR.
557 Restrict it to GIMPLE to avoid endless recursions. */
558 && (bitop != BIT_AND_EXPR || GIMPLE)
559 && (/* That's a good idea if the conversion widens the operand, thus
560 after hoisting the conversion the operation will be narrower. */
561 TYPE_PRECISION (TREE_TYPE (@0)) < TYPE_PRECISION (type)
562 /* It's also a good idea if the conversion is to a non-integer
563 mode. */
564 || GET_MODE_CLASS (TYPE_MODE (type)) != MODE_INT
565 /* Or if the precision of TO is not the same as the precision
566 of its mode. */
567 || TYPE_PRECISION (type) != GET_MODE_PRECISION (TYPE_MODE (type))))
568 (convert (bitop @0 (convert @1))))))
569
570 (for bitop (bit_and bit_ior)
571 rbitop (bit_ior bit_and)
572 /* (x | y) & x -> x */
573 /* (x & y) | x -> x */
574 (simplify
575 (bitop:c (rbitop:c @0 @1) @0)
576 @0)
577 /* (~x | y) & x -> x & y */
578 /* (~x & y) | x -> x | y */
579 (simplify
580 (bitop:c (rbitop:c (bit_not @0) @1) @0)
581 (bitop @0 @1)))
582
583 /* Simplify (A & B) OP0 (C & B) to (A OP0 C) & B. */
584 (for bitop (bit_and bit_ior bit_xor)
585 (simplify
586 (bitop (bit_and:c @0 @1) (bit_and @2 @1))
587 (bit_and (bitop @0 @2) @1)))
588
589 /* (x | CST1) & CST2 -> (x & CST2) | (CST1 & CST2) */
590 (simplify
591 (bit_and (bit_ior @0 CONSTANT_CLASS_P@1) CONSTANT_CLASS_P@2)
592 (bit_ior (bit_and @0 @2) (bit_and @1 @2)))
593
594 /* Combine successive equal operations with constants. */
595 (for bitop (bit_and bit_ior bit_xor)
596 (simplify
597 (bitop (bitop @0 CONSTANT_CLASS_P@1) CONSTANT_CLASS_P@2)
598 (bitop @0 (bitop @1 @2))))
599
600 /* Try simple folding for X op !X, and X op X with the help
601 of the truth_valued_p and logical_inverted_value predicates. */
602 (match truth_valued_p
603 @0
604 (if (INTEGRAL_TYPE_P (type) && TYPE_PRECISION (type) == 1)))
605 (for op (tcc_comparison truth_and truth_andif truth_or truth_orif truth_xor)
606 (match truth_valued_p
607 (op @0 @1)))
608 (match truth_valued_p
609 (truth_not @0))
610
611 (match (logical_inverted_value @0)
612 (bit_not truth_valued_p@0))
613 (match (logical_inverted_value @0)
614 (eq @0 integer_zerop))
615 (match (logical_inverted_value @0)
616 (ne truth_valued_p@0 integer_truep))
617 (match (logical_inverted_value @0)
618 (bit_xor truth_valued_p@0 integer_truep))
619
620 /* X & !X -> 0. */
621 (simplify
622 (bit_and:c @0 (logical_inverted_value @0))
623 { build_zero_cst (type); })
624 /* X | !X and X ^ !X -> 1, , if X is truth-valued. */
625 (for op (bit_ior bit_xor)
626 (simplify
627 (op:c truth_valued_p@0 (logical_inverted_value @0))
628 { constant_boolean_node (true, type); }))
629 /* X ==/!= !X is false/true. */
630 (for op (eq ne)
631 (simplify
632 (op:c truth_valued_p@0 (logical_inverted_value @0))
633 { constant_boolean_node (op == NE_EXPR ? true : false, type); }))
634
635 /* If arg1 and arg2 are booleans (or any single bit type)
636 then try to simplify:
637
638 (~X & Y) -> X < Y
639 (X & ~Y) -> Y < X
640 (~X | Y) -> X <= Y
641 (X | ~Y) -> Y <= X
642
643 But only do this if our result feeds into a comparison as
644 this transformation is not always a win, particularly on
645 targets with and-not instructions.
646 -> simplify_bitwise_binary_boolean */
647 (simplify
648 (ne (bit_and:c (bit_not @0) @1) integer_zerop)
649 (if (INTEGRAL_TYPE_P (TREE_TYPE (@1))
650 && TYPE_PRECISION (TREE_TYPE (@1)) == 1)
651 (lt @0 @1)))
652 (simplify
653 (ne (bit_ior:c (bit_not @0) @1) integer_zerop)
654 (if (INTEGRAL_TYPE_P (TREE_TYPE (@1))
655 && TYPE_PRECISION (TREE_TYPE (@1)) == 1)
656 (le @0 @1)))
657
658 /* ~~x -> x */
659 (simplify
660 (bit_not (bit_not @0))
661 @0)
662
663 /* Convert ~ (-A) to A - 1. */
664 (simplify
665 (bit_not (convert? (negate @0)))
666 (if (tree_nop_conversion_p (type, TREE_TYPE (@0)))
667 (convert (minus @0 { build_each_one_cst (TREE_TYPE (@0)); }))))
668
669 /* Convert ~ (A - 1) or ~ (A + -1) to -A. */
670 (simplify
671 (bit_not (convert? (minus @0 integer_each_onep)))
672 (if (tree_nop_conversion_p (type, TREE_TYPE (@0)))
673 (convert (negate @0))))
674 (simplify
675 (bit_not (convert? (plus @0 integer_all_onesp)))
676 (if (tree_nop_conversion_p (type, TREE_TYPE (@0)))
677 (convert (negate @0))))
678
679 /* Part of convert ~(X ^ Y) to ~X ^ Y or X ^ ~Y if ~X or ~Y simplify. */
680 (simplify
681 (bit_not (convert? (bit_xor @0 INTEGER_CST@1)))
682 (if (tree_nop_conversion_p (type, TREE_TYPE (@0)))
683 (convert (bit_xor @0 (bit_not @1)))))
684 (simplify
685 (bit_not (convert? (bit_xor:c (bit_not @0) @1)))
686 (if (tree_nop_conversion_p (type, TREE_TYPE (@0)))
687 (convert (bit_xor @0 @1))))
688
689 /* (x & ~m) | (y & m) -> ((x ^ y) & m) ^ x */
690 (simplify
691 (bit_ior:c (bit_and:cs @0 (bit_not @2)) (bit_and:cs @1 @2))
692 (bit_xor (bit_and (bit_xor @0 @1) @2) @0))
693
694 /* Fold A - (A & B) into ~B & A. */
695 (simplify
696 (minus (convert? @0) (convert?:s (bit_and:cs @0 @1)))
697 (if (tree_nop_conversion_p (type, TREE_TYPE (@0))
698 && tree_nop_conversion_p (type, TREE_TYPE (@1)))
699 (convert (bit_and (bit_not @1) @0))))
700
701 /* Associate (p +p off1) +p off2 as (p +p (off1 + off2)). */
702 (simplify
703 (pointer_plus (pointer_plus:s @0 @1) @3)
704 (pointer_plus @0 (plus @1 @3)))
705
706 /* Pattern match
707 tem1 = (long) ptr1;
708 tem2 = (long) ptr2;
709 tem3 = tem2 - tem1;
710 tem4 = (unsigned long) tem3;
711 tem5 = ptr1 + tem4;
712 and produce
713 tem5 = ptr2; */
714 (simplify
715 (pointer_plus @0 (convert?@2 (minus@3 (convert @1) (convert @0))))
716 /* Conditionally look through a sign-changing conversion. */
717 (if (TYPE_PRECISION (TREE_TYPE (@2)) == TYPE_PRECISION (TREE_TYPE (@3))
718 && ((GIMPLE && useless_type_conversion_p (type, TREE_TYPE (@1)))
719 || (GENERIC && type == TREE_TYPE (@1))))
720 @1))
721
722 /* Pattern match
723 tem = (sizetype) ptr;
724 tem = tem & algn;
725 tem = -tem;
726 ... = ptr p+ tem;
727 and produce the simpler and easier to analyze with respect to alignment
728 ... = ptr & ~algn; */
729 (simplify
730 (pointer_plus @0 (negate (bit_and (convert @0) INTEGER_CST@1)))
731 (with { tree algn = wide_int_to_tree (TREE_TYPE (@0), wi::bit_not (@1)); }
732 (bit_and @0 { algn; })))
733
734 /* Try folding difference of addresses. */
735 (simplify
736 (minus (convert ADDR_EXPR@0) (convert @1))
737 (if (tree_nop_conversion_p (type, TREE_TYPE (@0)))
738 (with { HOST_WIDE_INT diff; }
739 (if (ptr_difference_const (@0, @1, &diff))
740 { build_int_cst_type (type, diff); }))))
741 (simplify
742 (minus (convert @0) (convert ADDR_EXPR@1))
743 (if (tree_nop_conversion_p (type, TREE_TYPE (@0)))
744 (with { HOST_WIDE_INT diff; }
745 (if (ptr_difference_const (@0, @1, &diff))
746 { build_int_cst_type (type, diff); }))))
747
748 /* If arg0 is derived from the address of an object or function, we may
749 be able to fold this expression using the object or function's
750 alignment. */
751 (simplify
752 (bit_and (convert? @0) INTEGER_CST@1)
753 (if (POINTER_TYPE_P (TREE_TYPE (@0))
754 && tree_nop_conversion_p (type, TREE_TYPE (@0)))
755 (with
756 {
757 unsigned int align;
758 unsigned HOST_WIDE_INT bitpos;
759 get_pointer_alignment_1 (@0, &align, &bitpos);
760 }
761 (if (wi::ltu_p (@1, align / BITS_PER_UNIT))
762 { wide_int_to_tree (type, wi::bit_and (@1, bitpos / BITS_PER_UNIT)); }))))
763
764
765 /* We can't reassociate at all for saturating types. */
766 (if (!TYPE_SATURATING (type))
767
768 /* Contract negates. */
769 /* A + (-B) -> A - B */
770 (simplify
771 (plus:c (convert1? @0) (convert2? (negate @1)))
772 /* Apply STRIP_NOPS on @0 and the negate. */
773 (if (tree_nop_conversion_p (type, TREE_TYPE (@0))
774 && tree_nop_conversion_p (type, TREE_TYPE (@1))
775 && !TYPE_OVERFLOW_SANITIZED (type))
776 (minus (convert @0) (convert @1))))
777 /* A - (-B) -> A + B */
778 (simplify
779 (minus (convert1? @0) (convert2? (negate @1)))
780 (if (tree_nop_conversion_p (type, TREE_TYPE (@0))
781 && tree_nop_conversion_p (type, TREE_TYPE (@1))
782 && !TYPE_OVERFLOW_SANITIZED (type))
783 (plus (convert @0) (convert @1))))
784 /* -(-A) -> A */
785 (simplify
786 (negate (convert? (negate @1)))
787 (if (tree_nop_conversion_p (type, TREE_TYPE (@1))
788 && !TYPE_OVERFLOW_SANITIZED (type))
789 (convert @1)))
790
791 /* We can't reassociate floating-point unless -fassociative-math
792 or fixed-point plus or minus because of saturation to +-Inf. */
793 (if ((!FLOAT_TYPE_P (type) || flag_associative_math)
794 && !FIXED_POINT_TYPE_P (type))
795
796 /* Match patterns that allow contracting a plus-minus pair
797 irrespective of overflow issues. */
798 /* (A +- B) - A -> +- B */
799 /* (A +- B) -+ B -> A */
800 /* A - (A +- B) -> -+ B */
801 /* A +- (B -+ A) -> +- B */
802 (simplify
803 (minus (plus:c @0 @1) @0)
804 @1)
805 (simplify
806 (minus (minus @0 @1) @0)
807 (negate @1))
808 (simplify
809 (plus:c (minus @0 @1) @1)
810 @0)
811 (simplify
812 (minus @0 (plus:c @0 @1))
813 (negate @1))
814 (simplify
815 (minus @0 (minus @0 @1))
816 @1)
817
818 /* (A +- CST) +- CST -> A + CST */
819 (for outer_op (plus minus)
820 (for inner_op (plus minus)
821 (simplify
822 (outer_op (inner_op @0 CONSTANT_CLASS_P@1) CONSTANT_CLASS_P@2)
823 /* If the constant operation overflows we cannot do the transform
824 as we would introduce undefined overflow, for example
825 with (a - 1) + INT_MIN. */
826 (with { tree cst = fold_binary (outer_op == inner_op
827 ? PLUS_EXPR : MINUS_EXPR, type, @1, @2); }
828 (if (cst && !TREE_OVERFLOW (cst))
829 (inner_op @0 { cst; } ))))))
830
831 /* (CST - A) +- CST -> CST - A */
832 (for outer_op (plus minus)
833 (simplify
834 (outer_op (minus CONSTANT_CLASS_P@1 @0) CONSTANT_CLASS_P@2)
835 (with { tree cst = fold_binary (outer_op, type, @1, @2); }
836 (if (cst && !TREE_OVERFLOW (cst))
837 (minus { cst; } @0)))))
838
839 /* ~A + A -> -1 */
840 (simplify
841 (plus:c (bit_not @0) @0)
842 (if (!TYPE_OVERFLOW_TRAPS (type))
843 { build_all_ones_cst (type); }))
844
845 /* ~A + 1 -> -A */
846 (simplify
847 (plus (convert? (bit_not @0)) integer_each_onep)
848 (if (tree_nop_conversion_p (type, TREE_TYPE (@0)))
849 (negate (convert @0))))
850
851 /* -A - 1 -> ~A */
852 (simplify
853 (minus (convert? (negate @0)) integer_each_onep)
854 (if (!TYPE_OVERFLOW_TRAPS (type)
855 && tree_nop_conversion_p (type, TREE_TYPE (@0)))
856 (bit_not (convert @0))))
857
858 /* -1 - A -> ~A */
859 (simplify
860 (minus integer_all_onesp @0)
861 (bit_not @0))
862
863 /* (T)(P + A) - (T)P -> (T) A */
864 (for add (plus pointer_plus)
865 (simplify
866 (minus (convert (add @0 @1))
867 (convert @0))
868 (if (element_precision (type) <= element_precision (TREE_TYPE (@1))
869 /* For integer types, if A has a smaller type
870 than T the result depends on the possible
871 overflow in P + A.
872 E.g. T=size_t, A=(unsigned)429497295, P>0.
873 However, if an overflow in P + A would cause
874 undefined behavior, we can assume that there
875 is no overflow. */
876 || (INTEGRAL_TYPE_P (TREE_TYPE (@0))
877 && TYPE_OVERFLOW_UNDEFINED (TREE_TYPE (@0)))
878 /* For pointer types, if the conversion of A to the
879 final type requires a sign- or zero-extension,
880 then we have to punt - it is not defined which
881 one is correct. */
882 || (POINTER_TYPE_P (TREE_TYPE (@0))
883 && TREE_CODE (@1) == INTEGER_CST
884 && tree_int_cst_sign_bit (@1) == 0))
885 (convert @1))))))
886
887
888 /* Simplifications of MIN_EXPR and MAX_EXPR. */
889
890 (for minmax (min max)
891 (simplify
892 (minmax @0 @0)
893 @0))
894 (simplify
895 (min @0 @1)
896 (if (INTEGRAL_TYPE_P (type)
897 && TYPE_MIN_VALUE (type)
898 && operand_equal_p (@1, TYPE_MIN_VALUE (type), OEP_ONLY_CONST))
899 @1))
900 (simplify
901 (max @0 @1)
902 (if (INTEGRAL_TYPE_P (type)
903 && TYPE_MAX_VALUE (type)
904 && operand_equal_p (@1, TYPE_MAX_VALUE (type), OEP_ONLY_CONST))
905 @1))
906
907
908 /* Simplifications of shift and rotates. */
909
910 (for rotate (lrotate rrotate)
911 (simplify
912 (rotate integer_all_onesp@0 @1)
913 @0))
914
915 /* Optimize -1 >> x for arithmetic right shifts. */
916 (simplify
917 (rshift integer_all_onesp@0 @1)
918 (if (!TYPE_UNSIGNED (type)
919 && tree_expr_nonnegative_p (@1))
920 @0))
921
922 (for shiftrotate (lrotate rrotate lshift rshift)
923 (simplify
924 (shiftrotate @0 integer_zerop)
925 (non_lvalue @0))
926 (simplify
927 (shiftrotate integer_zerop@0 @1)
928 @0)
929 /* Prefer vector1 << scalar to vector1 << vector2
930 if vector2 is uniform. */
931 (for vec (VECTOR_CST CONSTRUCTOR)
932 (simplify
933 (shiftrotate @0 vec@1)
934 (with { tree tem = uniform_vector_p (@1); }
935 (if (tem)
936 (shiftrotate @0 { tem; }))))))
937
938 /* Rewrite an LROTATE_EXPR by a constant into an
939 RROTATE_EXPR by a new constant. */
940 (simplify
941 (lrotate @0 INTEGER_CST@1)
942 (rrotate @0 { fold_binary (MINUS_EXPR, TREE_TYPE (@1),
943 build_int_cst (TREE_TYPE (@1),
944 element_precision (type)), @1); }))
945
946 /* Turn (a OP c1) OP c2 into a OP (c1+c2). */
947 (for op (lrotate rrotate rshift lshift)
948 (simplify
949 (op (op @0 INTEGER_CST@1) INTEGER_CST@2)
950 (with { unsigned int prec = element_precision (type); }
951 (if (wi::ge_p (@1, 0, TYPE_SIGN (TREE_TYPE (@1)))
952 && wi::lt_p (@1, prec, TYPE_SIGN (TREE_TYPE (@1)))
953 && wi::ge_p (@2, 0, TYPE_SIGN (TREE_TYPE (@2)))
954 && wi::lt_p (@2, prec, TYPE_SIGN (TREE_TYPE (@2))))
955 (with { unsigned int low = wi::add (@1, @2).to_uhwi (); }
956 /* Deal with a OP (c1 + c2) being undefined but (a OP c1) OP c2
957 being well defined. */
958 (if (low >= prec)
959 (if (op == LROTATE_EXPR || op == RROTATE_EXPR)
960 (op @0 { build_int_cst (TREE_TYPE (@1), low % prec); })
961 (if (TYPE_UNSIGNED (type) || op == LSHIFT_EXPR)
962 { build_zero_cst (type); }
963 (op @0 { build_int_cst (TREE_TYPE (@1), prec - 1); })))
964 (op @0 { build_int_cst (TREE_TYPE (@1), low); })))))))
965
966
967 /* ((1 << A) & 1) != 0 -> A == 0
968 ((1 << A) & 1) == 0 -> A != 0 */
969 (for cmp (ne eq)
970 icmp (eq ne)
971 (simplify
972 (cmp (bit_and (lshift integer_onep @0) integer_onep) integer_zerop)
973 (icmp @0 { build_zero_cst (TREE_TYPE (@0)); })))
974
975 /* (CST1 << A) == CST2 -> A == ctz (CST2) - ctz (CST1)
976 (CST1 << A) != CST2 -> A != ctz (CST2) - ctz (CST1)
977 if CST2 != 0. */
978 (for cmp (ne eq)
979 (simplify
980 (cmp (lshift INTEGER_CST@0 @1) INTEGER_CST@2)
981 (with { int cand = wi::ctz (@2) - wi::ctz (@0); }
982 (if (cand < 0
983 || (!integer_zerop (@2)
984 && wi::ne_p (wi::lshift (@0, cand), @2)))
985 { constant_boolean_node (cmp == NE_EXPR, type); }
986 (if (!integer_zerop (@2)
987 && wi::eq_p (wi::lshift (@0, cand), @2))
988 (cmp @1 { build_int_cst (TREE_TYPE (@1), cand); }))))))
989
990 /* Fold (X << C1) & C2 into (X << C1) & (C2 | ((1 << C1) - 1))
991 (X >> C1) & C2 into (X >> C1) & (C2 | ~((type) -1 >> C1))
992 if the new mask might be further optimized. */
993 (for shift (lshift rshift)
994 (simplify
995 (bit_and (convert?:s@4 (shift:s@5 (convert1?@3 @0) INTEGER_CST@1))
996 INTEGER_CST@2)
997 (if (tree_nop_conversion_p (TREE_TYPE (@4), TREE_TYPE (@5))
998 && TYPE_PRECISION (type) <= HOST_BITS_PER_WIDE_INT
999 && tree_fits_uhwi_p (@1)
1000 && tree_to_uhwi (@1) > 0
1001 && tree_to_uhwi (@1) < TYPE_PRECISION (type))
1002 (with
1003 {
1004 unsigned int shiftc = tree_to_uhwi (@1);
1005 unsigned HOST_WIDE_INT mask = TREE_INT_CST_LOW (@2);
1006 unsigned HOST_WIDE_INT newmask, zerobits = 0;
1007 tree shift_type = TREE_TYPE (@3);
1008 unsigned int prec;
1009
1010 if (shift == LSHIFT_EXPR)
1011 zerobits = ((((unsigned HOST_WIDE_INT) 1) << shiftc) - 1);
1012 else if (shift == RSHIFT_EXPR
1013 && (TYPE_PRECISION (shift_type)
1014 == GET_MODE_PRECISION (TYPE_MODE (shift_type))))
1015 {
1016 prec = TYPE_PRECISION (TREE_TYPE (@3));
1017 tree arg00 = @0;
1018 /* See if more bits can be proven as zero because of
1019 zero extension. */
1020 if (@3 != @0
1021 && TYPE_UNSIGNED (TREE_TYPE (@0)))
1022 {
1023 tree inner_type = TREE_TYPE (@0);
1024 if ((TYPE_PRECISION (inner_type)
1025 == GET_MODE_PRECISION (TYPE_MODE (inner_type)))
1026 && TYPE_PRECISION (inner_type) < prec)
1027 {
1028 prec = TYPE_PRECISION (inner_type);
1029 /* See if we can shorten the right shift. */
1030 if (shiftc < prec)
1031 shift_type = inner_type;
1032 /* Otherwise X >> C1 is all zeros, so we'll optimize
1033 it into (X, 0) later on by making sure zerobits
1034 is all ones. */
1035 }
1036 }
1037 zerobits = ~(unsigned HOST_WIDE_INT) 0;
1038 if (shiftc < prec)
1039 {
1040 zerobits >>= HOST_BITS_PER_WIDE_INT - shiftc;
1041 zerobits <<= prec - shiftc;
1042 }
1043 /* For arithmetic shift if sign bit could be set, zerobits
1044 can contain actually sign bits, so no transformation is
1045 possible, unless MASK masks them all away. In that
1046 case the shift needs to be converted into logical shift. */
1047 if (!TYPE_UNSIGNED (TREE_TYPE (@3))
1048 && prec == TYPE_PRECISION (TREE_TYPE (@3)))
1049 {
1050 if ((mask & zerobits) == 0)
1051 shift_type = unsigned_type_for (TREE_TYPE (@3));
1052 else
1053 zerobits = 0;
1054 }
1055 }
1056 }
1057 /* ((X << 16) & 0xff00) is (X, 0). */
1058 (if ((mask & zerobits) == mask)
1059 { build_int_cst (type, 0); }
1060 (with { newmask = mask | zerobits; }
1061 (if (newmask != mask && (newmask & (newmask + 1)) == 0)
1062 (with
1063 {
1064 /* Only do the transformation if NEWMASK is some integer
1065 mode's mask. */
1066 for (prec = BITS_PER_UNIT;
1067 prec < HOST_BITS_PER_WIDE_INT; prec <<= 1)
1068 if (newmask == (((unsigned HOST_WIDE_INT) 1) << prec) - 1)
1069 break;
1070 }
1071 (if (prec < HOST_BITS_PER_WIDE_INT
1072 || newmask == ~(unsigned HOST_WIDE_INT) 0)
1073 (with
1074 { tree newmaskt = build_int_cst_type (TREE_TYPE (@2), newmask); }
1075 (if (!tree_int_cst_equal (newmaskt, @2))
1076 (if (shift_type != TREE_TYPE (@3))
1077 (bit_and (convert (shift:shift_type (convert @3) @1)) { newmaskt; })
1078 (bit_and @4 { newmaskt; })))))))))))))
1079
1080 /* Fold (X & C2) << C1 into (X << C1) & (C2 << C1)
1081 (X & C2) >> C1 into (X >> C1) & (C2 >> C1). */
1082 (for shift (lshift rshift)
1083 (simplify
1084 (shift (convert?:s (bit_and:s @0 INTEGER_CST@2)) INTEGER_CST@1)
1085 (if (tree_nop_conversion_p (type, TREE_TYPE (@0)))
1086 (with { tree mask = int_const_binop (shift, fold_convert (type, @2), @1); }
1087 (bit_and (shift (convert @0) @1) { mask; })))))
1088
1089
1090 /* Simplifications of conversions. */
1091
1092 /* Basic strip-useless-type-conversions / strip_nops. */
1093 (for cvt (convert view_convert float fix_trunc)
1094 (simplify
1095 (cvt @0)
1096 (if ((GIMPLE && useless_type_conversion_p (type, TREE_TYPE (@0)))
1097 || (GENERIC && type == TREE_TYPE (@0)))
1098 @0)))
1099
1100 /* Contract view-conversions. */
1101 (simplify
1102 (view_convert (view_convert @0))
1103 (view_convert @0))
1104
1105 /* For integral conversions with the same precision or pointer
1106 conversions use a NOP_EXPR instead. */
1107 (simplify
1108 (view_convert @0)
1109 (if ((INTEGRAL_TYPE_P (type) || POINTER_TYPE_P (type))
1110 && (INTEGRAL_TYPE_P (TREE_TYPE (@0)) || POINTER_TYPE_P (TREE_TYPE (@0)))
1111 && TYPE_PRECISION (type) == TYPE_PRECISION (TREE_TYPE (@0)))
1112 (convert @0)))
1113
1114 /* Strip inner integral conversions that do not change precision or size. */
1115 (simplify
1116 (view_convert (convert@0 @1))
1117 (if ((INTEGRAL_TYPE_P (TREE_TYPE (@0)) || POINTER_TYPE_P (TREE_TYPE (@0)))
1118 && (INTEGRAL_TYPE_P (TREE_TYPE (@1)) || POINTER_TYPE_P (TREE_TYPE (@1)))
1119 && (TYPE_PRECISION (TREE_TYPE (@0)) == TYPE_PRECISION (TREE_TYPE (@1)))
1120 && (TYPE_SIZE (TREE_TYPE (@0)) == TYPE_SIZE (TREE_TYPE (@1))))
1121 (view_convert @1)))
1122
1123 /* Re-association barriers around constants and other re-association
1124 barriers can be removed. */
1125 (simplify
1126 (paren CONSTANT_CLASS_P@0)
1127 @0)
1128 (simplify
1129 (paren (paren@1 @0))
1130 @1)
1131
1132 /* Handle cases of two conversions in a row. */
1133 (for ocvt (convert float fix_trunc)
1134 (for icvt (convert float)
1135 (simplify
1136 (ocvt (icvt@1 @0))
1137 (with
1138 {
1139 tree inside_type = TREE_TYPE (@0);
1140 tree inter_type = TREE_TYPE (@1);
1141 int inside_int = INTEGRAL_TYPE_P (inside_type);
1142 int inside_ptr = POINTER_TYPE_P (inside_type);
1143 int inside_float = FLOAT_TYPE_P (inside_type);
1144 int inside_vec = VECTOR_TYPE_P (inside_type);
1145 unsigned int inside_prec = TYPE_PRECISION (inside_type);
1146 int inside_unsignedp = TYPE_UNSIGNED (inside_type);
1147 int inter_int = INTEGRAL_TYPE_P (inter_type);
1148 int inter_ptr = POINTER_TYPE_P (inter_type);
1149 int inter_float = FLOAT_TYPE_P (inter_type);
1150 int inter_vec = VECTOR_TYPE_P (inter_type);
1151 unsigned int inter_prec = TYPE_PRECISION (inter_type);
1152 int inter_unsignedp = TYPE_UNSIGNED (inter_type);
1153 int final_int = INTEGRAL_TYPE_P (type);
1154 int final_ptr = POINTER_TYPE_P (type);
1155 int final_float = FLOAT_TYPE_P (type);
1156 int final_vec = VECTOR_TYPE_P (type);
1157 unsigned int final_prec = TYPE_PRECISION (type);
1158 int final_unsignedp = TYPE_UNSIGNED (type);
1159 }
1160 (switch
1161 /* In addition to the cases of two conversions in a row
1162 handled below, if we are converting something to its own
1163 type via an object of identical or wider precision, neither
1164 conversion is needed. */
1165 (if (((GIMPLE && useless_type_conversion_p (type, inside_type))
1166 || (GENERIC
1167 && TYPE_MAIN_VARIANT (type) == TYPE_MAIN_VARIANT (inside_type)))
1168 && (((inter_int || inter_ptr) && final_int)
1169 || (inter_float && final_float))
1170 && inter_prec >= final_prec)
1171 (ocvt @0))
1172
1173 /* Likewise, if the intermediate and initial types are either both
1174 float or both integer, we don't need the middle conversion if the
1175 former is wider than the latter and doesn't change the signedness
1176 (for integers). Avoid this if the final type is a pointer since
1177 then we sometimes need the middle conversion. Likewise if the
1178 final type has a precision not equal to the size of its mode. */
1179 (if (((inter_int && inside_int) || (inter_float && inside_float))
1180 && (final_int || final_float)
1181 && inter_prec >= inside_prec
1182 && (inter_float || inter_unsignedp == inside_unsignedp)
1183 && ! (final_prec != GET_MODE_PRECISION (TYPE_MODE (type))
1184 && TYPE_MODE (type) == TYPE_MODE (inter_type)))
1185 (ocvt @0))
1186
1187 /* If we have a sign-extension of a zero-extended value, we can
1188 replace that by a single zero-extension. Likewise if the
1189 final conversion does not change precision we can drop the
1190 intermediate conversion. */
1191 (if (inside_int && inter_int && final_int
1192 && ((inside_prec < inter_prec && inter_prec < final_prec
1193 && inside_unsignedp && !inter_unsignedp)
1194 || final_prec == inter_prec))
1195 (ocvt @0))
1196
1197 /* Two conversions in a row are not needed unless:
1198 - some conversion is floating-point (overstrict for now), or
1199 - some conversion is a vector (overstrict for now), or
1200 - the intermediate type is narrower than both initial and
1201 final, or
1202 - the intermediate type and innermost type differ in signedness,
1203 and the outermost type is wider than the intermediate, or
1204 - the initial type is a pointer type and the precisions of the
1205 intermediate and final types differ, or
1206 - the final type is a pointer type and the precisions of the
1207 initial and intermediate types differ. */
1208 (if (! inside_float && ! inter_float && ! final_float
1209 && ! inside_vec && ! inter_vec && ! final_vec
1210 && (inter_prec >= inside_prec || inter_prec >= final_prec)
1211 && ! (inside_int && inter_int
1212 && inter_unsignedp != inside_unsignedp
1213 && inter_prec < final_prec)
1214 && ((inter_unsignedp && inter_prec > inside_prec)
1215 == (final_unsignedp && final_prec > inter_prec))
1216 && ! (inside_ptr && inter_prec != final_prec)
1217 && ! (final_ptr && inside_prec != inter_prec)
1218 && ! (final_prec != GET_MODE_PRECISION (TYPE_MODE (type))
1219 && TYPE_MODE (type) == TYPE_MODE (inter_type)))
1220 (ocvt @0))
1221
1222 /* A truncation to an unsigned type (a zero-extension) should be
1223 canonicalized as bitwise and of a mask. */
1224 (if (final_int && inter_int && inside_int
1225 && final_prec == inside_prec
1226 && final_prec > inter_prec
1227 && inter_unsignedp)
1228 (convert (bit_and @0 { wide_int_to_tree
1229 (inside_type,
1230 wi::mask (inter_prec, false,
1231 TYPE_PRECISION (inside_type))); })))
1232
1233 /* If we are converting an integer to a floating-point that can
1234 represent it exactly and back to an integer, we can skip the
1235 floating-point conversion. */
1236 (if (GIMPLE /* PR66211 */
1237 && inside_int && inter_float && final_int &&
1238 (unsigned) significand_size (TYPE_MODE (inter_type))
1239 >= inside_prec - !inside_unsignedp)
1240 (convert @0)))))))
1241
1242 /* If we have a narrowing conversion to an integral type that is fed by a
1243 BIT_AND_EXPR, we might be able to remove the BIT_AND_EXPR if it merely
1244 masks off bits outside the final type (and nothing else). */
1245 (simplify
1246 (convert (bit_and @0 INTEGER_CST@1))
1247 (if (INTEGRAL_TYPE_P (type)
1248 && INTEGRAL_TYPE_P (TREE_TYPE (@0))
1249 && TYPE_PRECISION (type) <= TYPE_PRECISION (TREE_TYPE (@0))
1250 && operand_equal_p (@1, build_low_bits_mask (TREE_TYPE (@1),
1251 TYPE_PRECISION (type)), 0))
1252 (convert @0)))
1253
1254
1255 /* (X /[ex] A) * A -> X. */
1256 (simplify
1257 (mult (convert? (exact_div @0 @1)) @1)
1258 /* Look through a sign-changing conversion. */
1259 (convert @0))
1260
1261 /* Canonicalization of binary operations. */
1262
1263 /* Convert X + -C into X - C. */
1264 (simplify
1265 (plus @0 REAL_CST@1)
1266 (if (REAL_VALUE_NEGATIVE (TREE_REAL_CST (@1)))
1267 (with { tree tem = fold_unary (NEGATE_EXPR, type, @1); }
1268 (if (!TREE_OVERFLOW (tem) || !flag_trapping_math)
1269 (minus @0 { tem; })))))
1270
1271 /* Convert x+x into x*2.0. */
1272 (simplify
1273 (plus @0 @0)
1274 (if (SCALAR_FLOAT_TYPE_P (type))
1275 (mult @0 { build_real (type, dconst2); })))
1276
1277 (simplify
1278 (minus integer_zerop @1)
1279 (negate @1))
1280
1281 /* (ARG0 - ARG1) is the same as (-ARG1 + ARG0). So check whether
1282 ARG0 is zero and X + ARG0 reduces to X, since that would mean
1283 (-ARG1 + ARG0) reduces to -ARG1. */
1284 (simplify
1285 (minus real_zerop@0 @1)
1286 (if (fold_real_zero_addition_p (type, @0, 0))
1287 (negate @1)))
1288
1289 /* Transform x * -1 into -x. */
1290 (simplify
1291 (mult @0 integer_minus_onep)
1292 (negate @0))
1293
1294 /* COMPLEX_EXPR and REALPART/IMAGPART_EXPR cancellations. */
1295 (simplify
1296 (complex (realpart @0) (imagpart @0))
1297 @0)
1298 (simplify
1299 (realpart (complex @0 @1))
1300 @0)
1301 (simplify
1302 (imagpart (complex @0 @1))
1303 @1)
1304
1305
1306 /* BSWAP simplifications, transforms checked by gcc.dg/builtin-bswap-8.c. */
1307 (for bswap (BUILT_IN_BSWAP16 BUILT_IN_BSWAP32 BUILT_IN_BSWAP64)
1308 (simplify
1309 (bswap (bswap @0))
1310 @0)
1311 (simplify
1312 (bswap (bit_not (bswap @0)))
1313 (bit_not @0))
1314 (for bitop (bit_xor bit_ior bit_and)
1315 (simplify
1316 (bswap (bitop:c (bswap @0) @1))
1317 (bitop @0 (bswap @1)))))
1318
1319
1320 /* Combine COND_EXPRs and VEC_COND_EXPRs. */
1321
1322 /* Simplify constant conditions.
1323 Only optimize constant conditions when the selected branch
1324 has the same type as the COND_EXPR. This avoids optimizing
1325 away "c ? x : throw", where the throw has a void type.
1326 Note that we cannot throw away the fold-const.c variant nor
1327 this one as we depend on doing this transform before possibly
1328 A ? B : B -> B triggers and the fold-const.c one can optimize
1329 0 ? A : B to B even if A has side-effects. Something
1330 genmatch cannot handle. */
1331 (simplify
1332 (cond INTEGER_CST@0 @1 @2)
1333 (if (integer_zerop (@0))
1334 (if (!VOID_TYPE_P (TREE_TYPE (@2)) || VOID_TYPE_P (type))
1335 @2)
1336 (if (!VOID_TYPE_P (TREE_TYPE (@1)) || VOID_TYPE_P (type))
1337 @1)))
1338 (simplify
1339 (vec_cond VECTOR_CST@0 @1 @2)
1340 (if (integer_all_onesp (@0))
1341 @1
1342 (if (integer_zerop (@0))
1343 @2)))
1344
1345 (for cnd (cond vec_cond)
1346 /* A ? B : (A ? X : C) -> A ? B : C. */
1347 (simplify
1348 (cnd @0 (cnd @0 @1 @2) @3)
1349 (cnd @0 @1 @3))
1350 (simplify
1351 (cnd @0 @1 (cnd @0 @2 @3))
1352 (cnd @0 @1 @3))
1353
1354 /* A ? B : B -> B. */
1355 (simplify
1356 (cnd @0 @1 @1)
1357 @1)
1358
1359 /* !A ? B : C -> A ? C : B. */
1360 (simplify
1361 (cnd (logical_inverted_value truth_valued_p@0) @1 @2)
1362 (cnd @0 @2 @1)))
1363
1364 /* A + (B vcmp C ? 1 : 0) -> A - (B vcmp C), since vector comparisons
1365 return all-1 or all-0 results. */
1366 /* ??? We could instead convert all instances of the vec_cond to negate,
1367 but that isn't necessarily a win on its own. */
1368 (simplify
1369 (plus:c @3 (view_convert? (vec_cond @0 integer_each_onep@1 integer_zerop@2)))
1370 (if (VECTOR_TYPE_P (type)
1371 && TYPE_VECTOR_SUBPARTS (type) == TYPE_VECTOR_SUBPARTS (TREE_TYPE (@0))
1372 && (TYPE_MODE (TREE_TYPE (type))
1373 == TYPE_MODE (TREE_TYPE (TREE_TYPE (@0)))))
1374 (minus @3 (view_convert @0))))
1375
1376 /* ... likewise A - (B vcmp C ? 1 : 0) -> A + (B vcmp C). */
1377 (simplify
1378 (minus @3 (view_convert? (vec_cond @0 integer_each_onep@1 integer_zerop@2)))
1379 (if (VECTOR_TYPE_P (type)
1380 && TYPE_VECTOR_SUBPARTS (type) == TYPE_VECTOR_SUBPARTS (TREE_TYPE (@0))
1381 && (TYPE_MODE (TREE_TYPE (type))
1382 == TYPE_MODE (TREE_TYPE (TREE_TYPE (@0)))))
1383 (plus @3 (view_convert @0))))
1384
1385
1386 /* Simplifications of comparisons. */
1387
1388 /* See if we can reduce the magnitude of a constant involved in a
1389 comparison by changing the comparison code. This is a canonicalization
1390 formerly done by maybe_canonicalize_comparison_1. */
1391 (for cmp (le gt)
1392 acmp (lt ge)
1393 (simplify
1394 (cmp @0 INTEGER_CST@1)
1395 (if (tree_int_cst_sgn (@1) == -1)
1396 (acmp @0 { wide_int_to_tree (TREE_TYPE (@1), wi::add (@1, 1)); }))))
1397 (for cmp (ge lt)
1398 acmp (gt le)
1399 (simplify
1400 (cmp @0 INTEGER_CST@1)
1401 (if (tree_int_cst_sgn (@1) == 1)
1402 (acmp @0 { wide_int_to_tree (TREE_TYPE (@1), wi::sub (@1, 1)); }))))
1403
1404
1405 /* We can simplify a logical negation of a comparison to the
1406 inverted comparison. As we cannot compute an expression
1407 operator using invert_tree_comparison we have to simulate
1408 that with expression code iteration. */
1409 (for cmp (tcc_comparison)
1410 icmp (inverted_tcc_comparison)
1411 ncmp (inverted_tcc_comparison_with_nans)
1412 /* Ideally we'd like to combine the following two patterns
1413 and handle some more cases by using
1414 (logical_inverted_value (cmp @0 @1))
1415 here but for that genmatch would need to "inline" that.
1416 For now implement what forward_propagate_comparison did. */
1417 (simplify
1418 (bit_not (cmp @0 @1))
1419 (if (VECTOR_TYPE_P (type)
1420 || (INTEGRAL_TYPE_P (type) && TYPE_PRECISION (type) == 1))
1421 /* Comparison inversion may be impossible for trapping math,
1422 invert_tree_comparison will tell us. But we can't use
1423 a computed operator in the replacement tree thus we have
1424 to play the trick below. */
1425 (with { enum tree_code ic = invert_tree_comparison
1426 (cmp, HONOR_NANS (@0)); }
1427 (if (ic == icmp)
1428 (icmp @0 @1)
1429 (if (ic == ncmp)
1430 (ncmp @0 @1))))))
1431 (simplify
1432 (bit_xor (cmp @0 @1) integer_truep)
1433 (with { enum tree_code ic = invert_tree_comparison
1434 (cmp, HONOR_NANS (@0)); }
1435 (if (ic == icmp)
1436 (icmp @0 @1)
1437 (if (ic == ncmp)
1438 (ncmp @0 @1))))))
1439
1440 /* Transform comparisons of the form X - Y CMP 0 to X CMP Y.
1441 ??? The transformation is valid for the other operators if overflow
1442 is undefined for the type, but performing it here badly interacts
1443 with the transformation in fold_cond_expr_with_comparison which
1444 attempts to synthetize ABS_EXPR. */
1445 (for cmp (eq ne)
1446 (simplify
1447 (cmp (minus@2 @0 @1) integer_zerop)
1448 (if (single_use (@2))
1449 (cmp @0 @1))))
1450
1451 /* Transform comparisons of the form X * C1 CMP 0 to X CMP 0 in the
1452 signed arithmetic case. That form is created by the compiler
1453 often enough for folding it to be of value. One example is in
1454 computing loop trip counts after Operator Strength Reduction. */
1455 (for cmp (simple_comparison)
1456 scmp (swapped_simple_comparison)
1457 (simplify
1458 (cmp (mult @0 INTEGER_CST@1) integer_zerop@2)
1459 /* Handle unfolded multiplication by zero. */
1460 (if (integer_zerop (@1))
1461 (cmp @1 @2)
1462 (if (ANY_INTEGRAL_TYPE_P (TREE_TYPE (@0))
1463 && TYPE_OVERFLOW_UNDEFINED (TREE_TYPE (@0)))
1464 /* If @1 is negative we swap the sense of the comparison. */
1465 (if (tree_int_cst_sgn (@1) < 0)
1466 (scmp @0 @2)
1467 (cmp @0 @2))))))
1468
1469 /* Simplify comparison of something with itself. For IEEE
1470 floating-point, we can only do some of these simplifications. */
1471 (simplify
1472 (eq @0 @0)
1473 (if (! FLOAT_TYPE_P (TREE_TYPE (@0))
1474 || ! HONOR_NANS (TYPE_MODE (TREE_TYPE (@0))))
1475 { constant_boolean_node (true, type); }))
1476 (for cmp (ge le)
1477 (simplify
1478 (cmp @0 @0)
1479 (eq @0 @0)))
1480 (for cmp (ne gt lt)
1481 (simplify
1482 (cmp @0 @0)
1483 (if (cmp != NE_EXPR
1484 || ! FLOAT_TYPE_P (TREE_TYPE (@0))
1485 || ! HONOR_NANS (TYPE_MODE (TREE_TYPE (@0))))
1486 { constant_boolean_node (false, type); })))
1487 (for cmp (unle unge uneq)
1488 (simplify
1489 (cmp @0 @0)
1490 { constant_boolean_node (true, type); }))
1491 (simplify
1492 (ltgt @0 @0)
1493 (if (!flag_trapping_math)
1494 { constant_boolean_node (false, type); }))
1495
1496 /* Fold ~X op ~Y as Y op X. */
1497 (for cmp (simple_comparison)
1498 (simplify
1499 (cmp (bit_not @0) (bit_not @1))
1500 (cmp @1 @0)))
1501
1502 /* Fold ~X op C as X op' ~C, where op' is the swapped comparison. */
1503 (for cmp (simple_comparison)
1504 scmp (swapped_simple_comparison)
1505 (simplify
1506 (cmp (bit_not @0) CONSTANT_CLASS_P@1)
1507 (if (TREE_CODE (@1) == INTEGER_CST || TREE_CODE (@1) == VECTOR_CST)
1508 (scmp @0 (bit_not @1)))))
1509
1510 (for cmp (simple_comparison)
1511 /* Fold (double)float1 CMP (double)float2 into float1 CMP float2. */
1512 (simplify
1513 (cmp (convert@2 @0) (convert? @1))
1514 (if (FLOAT_TYPE_P (TREE_TYPE (@0))
1515 && (DECIMAL_FLOAT_TYPE_P (TREE_TYPE (@2))
1516 == DECIMAL_FLOAT_TYPE_P (TREE_TYPE (@0)))
1517 && (DECIMAL_FLOAT_TYPE_P (TREE_TYPE (@2))
1518 == DECIMAL_FLOAT_TYPE_P (TREE_TYPE (@1))))
1519 (with
1520 {
1521 tree type1 = TREE_TYPE (@1);
1522 if (TREE_CODE (@1) == REAL_CST && !DECIMAL_FLOAT_TYPE_P (type1))
1523 {
1524 REAL_VALUE_TYPE orig = TREE_REAL_CST (@1);
1525 if (TYPE_PRECISION (type1) > TYPE_PRECISION (float_type_node)
1526 && exact_real_truncate (TYPE_MODE (float_type_node), &orig))
1527 type1 = float_type_node;
1528 if (TYPE_PRECISION (type1) > TYPE_PRECISION (double_type_node)
1529 && exact_real_truncate (TYPE_MODE (double_type_node), &orig))
1530 type1 = double_type_node;
1531 }
1532 tree newtype
1533 = (TYPE_PRECISION (TREE_TYPE (@0)) > TYPE_PRECISION (type1)
1534 ? TREE_TYPE (@0) : type1);
1535 }
1536 (if (TYPE_PRECISION (TREE_TYPE (@2)) > TYPE_PRECISION (newtype))
1537 (cmp (convert:newtype @0) (convert:newtype @1))))))
1538
1539 (simplify
1540 (cmp @0 REAL_CST@1)
1541 /* IEEE doesn't distinguish +0 and -0 in comparisons. */
1542 (switch
1543 /* a CMP (-0) -> a CMP 0 */
1544 (if (REAL_VALUE_MINUS_ZERO (TREE_REAL_CST (@1)))
1545 (cmp @0 { build_real (TREE_TYPE (@1), dconst0); }))
1546 /* x != NaN is always true, other ops are always false. */
1547 (if (REAL_VALUE_ISNAN (TREE_REAL_CST (@1))
1548 && ! HONOR_SNANS (@1))
1549 { constant_boolean_node (cmp == NE_EXPR, type); })
1550 /* Fold comparisons against infinity. */
1551 (if (REAL_VALUE_ISINF (TREE_REAL_CST (@1))
1552 && MODE_HAS_INFINITIES (TYPE_MODE (TREE_TYPE (@1))))
1553 (with
1554 {
1555 REAL_VALUE_TYPE max;
1556 enum tree_code code = cmp;
1557 bool neg = REAL_VALUE_NEGATIVE (TREE_REAL_CST (@1));
1558 if (neg)
1559 code = swap_tree_comparison (code);
1560 }
1561 (switch
1562 /* x > +Inf is always false, if with ignore sNANs. */
1563 (if (code == GT_EXPR
1564 && ! HONOR_SNANS (@0))
1565 { constant_boolean_node (false, type); })
1566 (if (code == LE_EXPR)
1567 /* x <= +Inf is always true, if we don't case about NaNs. */
1568 (if (! HONOR_NANS (@0))
1569 { constant_boolean_node (true, type); }
1570 /* x <= +Inf is the same as x == x, i.e. isfinite(x). */
1571 (eq @0 @0)))
1572 /* x == +Inf and x >= +Inf are always equal to x > DBL_MAX. */
1573 (if (code == EQ_EXPR || code == GE_EXPR)
1574 (with { real_maxval (&max, neg, TYPE_MODE (TREE_TYPE (@0))); }
1575 (if (neg)
1576 (lt @0 { build_real (TREE_TYPE (@0), max); })
1577 (gt @0 { build_real (TREE_TYPE (@0), max); }))))
1578 /* x < +Inf is always equal to x <= DBL_MAX. */
1579 (if (code == LT_EXPR)
1580 (with { real_maxval (&max, neg, TYPE_MODE (TREE_TYPE (@0))); }
1581 (if (neg)
1582 (ge @0 { build_real (TREE_TYPE (@0), max); })
1583 (le @0 { build_real (TREE_TYPE (@0), max); }))))
1584 /* x != +Inf is always equal to !(x > DBL_MAX). */
1585 (if (code == NE_EXPR)
1586 (with { real_maxval (&max, neg, TYPE_MODE (TREE_TYPE (@0))); }
1587 (if (! HONOR_NANS (@0))
1588 (if (neg)
1589 (ge @0 { build_real (TREE_TYPE (@0), max); })
1590 (le @0 { build_real (TREE_TYPE (@0), max); }))
1591 (if (neg)
1592 (bit_xor (lt @0 { build_real (TREE_TYPE (@0), max); })
1593 { build_one_cst (type); })
1594 (bit_xor (gt @0 { build_real (TREE_TYPE (@0), max); })
1595 { build_one_cst (type); }))))))))))
1596
1597 /* If this is a comparison of a real constant with a PLUS_EXPR
1598 or a MINUS_EXPR of a real constant, we can convert it into a
1599 comparison with a revised real constant as long as no overflow
1600 occurs when unsafe_math_optimizations are enabled. */
1601 (if (flag_unsafe_math_optimizations)
1602 (for op (plus minus)
1603 (simplify
1604 (cmp (op @0 REAL_CST@1) REAL_CST@2)
1605 (with
1606 {
1607 tree tem = const_binop (op == PLUS_EXPR ? MINUS_EXPR : PLUS_EXPR,
1608 TREE_TYPE (@1), @2, @1);
1609 }
1610 (if (tem && !TREE_OVERFLOW (tem))
1611 (cmp @0 { tem; }))))))
1612
1613 /* Likewise, we can simplify a comparison of a real constant with
1614 a MINUS_EXPR whose first operand is also a real constant, i.e.
1615 (c1 - x) < c2 becomes x > c1-c2. Reordering is allowed on
1616 floating-point types only if -fassociative-math is set. */
1617 (if (flag_associative_math)
1618 (simplify
1619 (cmp (minus REAL_CST@0 @1) REAL_CST@2)
1620 (with { tree tem = const_binop (MINUS_EXPR, TREE_TYPE (@1), @0, @2); }
1621 (if (tem && !TREE_OVERFLOW (tem))
1622 (cmp { tem; } @1)))))
1623
1624 /* Fold comparisons against built-in math functions. */
1625 (if (flag_unsafe_math_optimizations
1626 && ! flag_errno_math)
1627 (for sq (SQRT)
1628 (simplify
1629 (cmp (sq @0) REAL_CST@1)
1630 (switch
1631 (if (REAL_VALUE_NEGATIVE (TREE_REAL_CST (@1)))
1632 (switch
1633 /* sqrt(x) < y is always false, if y is negative. */
1634 (if (cmp == EQ_EXPR || cmp == LT_EXPR || cmp == LE_EXPR)
1635 { constant_boolean_node (false, type); })
1636 /* sqrt(x) > y is always true, if y is negative and we
1637 don't care about NaNs, i.e. negative values of x. */
1638 (if (cmp == NE_EXPR || !HONOR_NANS (@0))
1639 { constant_boolean_node (true, type); })
1640 /* sqrt(x) > y is the same as x >= 0, if y is negative. */
1641 (ge @0 { build_real (TREE_TYPE (@0), dconst0); })))
1642 (if (cmp == GT_EXPR || cmp == GE_EXPR)
1643 (with
1644 {
1645 REAL_VALUE_TYPE c2;
1646 REAL_ARITHMETIC (c2, MULT_EXPR,
1647 TREE_REAL_CST (@1), TREE_REAL_CST (@1));
1648 real_convert (&c2, TYPE_MODE (TREE_TYPE (@0)), &c2);
1649 }
1650 (if (REAL_VALUE_ISINF (c2))
1651 /* sqrt(x) > y is x == +Inf, when y is very large. */
1652 (if (HONOR_INFINITIES (@0))
1653 (eq @0 { build_real (TREE_TYPE (@0), c2); })
1654 { constant_boolean_node (false, type); })
1655 /* sqrt(x) > c is the same as x > c*c. */
1656 (cmp @0 { build_real (TREE_TYPE (@0), c2); }))))
1657 (if (cmp == LT_EXPR || cmp == LE_EXPR)
1658 (with
1659 {
1660 REAL_VALUE_TYPE c2;
1661 REAL_ARITHMETIC (c2, MULT_EXPR,
1662 TREE_REAL_CST (@1), TREE_REAL_CST (@1));
1663 real_convert (&c2, TYPE_MODE (TREE_TYPE (@0)), &c2);
1664 }
1665 (if (REAL_VALUE_ISINF (c2))
1666 (switch
1667 /* sqrt(x) < y is always true, when y is a very large
1668 value and we don't care about NaNs or Infinities. */
1669 (if (! HONOR_NANS (@0) && ! HONOR_INFINITIES (@0))
1670 { constant_boolean_node (true, type); })
1671 /* sqrt(x) < y is x != +Inf when y is very large and we
1672 don't care about NaNs. */
1673 (if (! HONOR_NANS (@0))
1674 (ne @0 { build_real (TREE_TYPE (@0), c2); }))
1675 /* sqrt(x) < y is x >= 0 when y is very large and we
1676 don't care about Infinities. */
1677 (if (! HONOR_INFINITIES (@0))
1678 (ge @0 { build_real (TREE_TYPE (@0), dconst0); }))
1679 /* sqrt(x) < y is x >= 0 && x != +Inf, when y is large. */
1680 (if (GENERIC)
1681 (truth_andif
1682 (ge @0 { build_real (TREE_TYPE (@0), dconst0); })
1683 (ne @0 { build_real (TREE_TYPE (@0), c2); }))))
1684 /* sqrt(x) < c is the same as x < c*c, if we ignore NaNs. */
1685 (if (! HONOR_NANS (@0))
1686 (cmp @0 { build_real (TREE_TYPE (@0), c2); })
1687 /* sqrt(x) < c is the same as x >= 0 && x < c*c. */
1688 (if (GENERIC)
1689 (truth_andif
1690 (ge @0 { build_real (TREE_TYPE (@0), dconst0); })
1691 (cmp @0 { build_real (TREE_TYPE (@0), c2); }))))))))))))
1692
1693 /* Unordered tests if either argument is a NaN. */
1694 (simplify
1695 (bit_ior (unordered @0 @0) (unordered @1 @1))
1696 (if (types_match (@0, @1))
1697 (unordered @0 @1)))
1698 (simplify
1699 (bit_and (ordered @0 @0) (ordered @1 @1))
1700 (if (types_match (@0, @1))
1701 (ordered @0 @1)))
1702 (simplify
1703 (bit_ior:c (unordered @0 @0) (unordered:c@2 @0 @1))
1704 @2)
1705 (simplify
1706 (bit_and:c (ordered @0 @0) (ordered:c@2 @0 @1))
1707 @2)
1708
1709 /* -A CMP -B -> B CMP A. */
1710 (for cmp (tcc_comparison)
1711 scmp (swapped_tcc_comparison)
1712 (simplify
1713 (cmp (negate @0) (negate @1))
1714 (if (FLOAT_TYPE_P (TREE_TYPE (@0))
1715 || (ANY_INTEGRAL_TYPE_P (TREE_TYPE (@0))
1716 && TYPE_OVERFLOW_UNDEFINED (TREE_TYPE (@0))))
1717 (scmp @0 @1)))
1718 (simplify
1719 (cmp (negate @0) CONSTANT_CLASS_P@1)
1720 (if (FLOAT_TYPE_P (TREE_TYPE (@0))
1721 || (ANY_INTEGRAL_TYPE_P (TREE_TYPE (@0))
1722 && TYPE_OVERFLOW_UNDEFINED (TREE_TYPE (@0))))
1723 (with { tree tem = fold_unary (NEGATE_EXPR, TREE_TYPE (@0), @1); }
1724 (if (tem && !TREE_OVERFLOW (tem))
1725 (scmp @0 { tem; }))))))
1726
1727 /* From fold_sign_changed_comparison and fold_widened_comparison. */
1728 (for cmp (simple_comparison)
1729 (simplify
1730 (cmp (convert@0 @00) (convert?@1 @10))
1731 (if (TREE_CODE (TREE_TYPE (@0)) == INTEGER_TYPE
1732 /* Disable this optimization if we're casting a function pointer
1733 type on targets that require function pointer canonicalization. */
1734 && !(targetm.have_canonicalize_funcptr_for_compare ()
1735 && TREE_CODE (TREE_TYPE (@00)) == POINTER_TYPE
1736 && TREE_CODE (TREE_TYPE (TREE_TYPE (@00))) == FUNCTION_TYPE)
1737 && single_use (@0))
1738 (if (TYPE_PRECISION (TREE_TYPE (@00)) == TYPE_PRECISION (TREE_TYPE (@0))
1739 && (TREE_CODE (@10) == INTEGER_CST
1740 || (@1 != @10 && types_match (TREE_TYPE (@10), TREE_TYPE (@00))))
1741 && (TYPE_UNSIGNED (TREE_TYPE (@00)) == TYPE_UNSIGNED (TREE_TYPE (@0))
1742 || cmp == NE_EXPR
1743 || cmp == EQ_EXPR)
1744 && (POINTER_TYPE_P (TREE_TYPE (@00)) == POINTER_TYPE_P (TREE_TYPE (@0))))
1745 /* ??? The special-casing of INTEGER_CST conversion was in the original
1746 code and here to avoid a spurious overflow flag on the resulting
1747 constant which fold_convert produces. */
1748 (if (TREE_CODE (@1) == INTEGER_CST)
1749 (cmp @00 { force_fit_type (TREE_TYPE (@00), wi::to_widest (@1), 0,
1750 TREE_OVERFLOW (@1)); })
1751 (cmp @00 (convert @1)))
1752
1753 (if (TYPE_PRECISION (TREE_TYPE (@0)) > TYPE_PRECISION (TREE_TYPE (@00)))
1754 /* If possible, express the comparison in the shorter mode. */
1755 (if ((cmp == EQ_EXPR || cmp == NE_EXPR
1756 || TYPE_UNSIGNED (TREE_TYPE (@0)) == TYPE_UNSIGNED (TREE_TYPE (@00)))
1757 && (types_match (TREE_TYPE (@10), TREE_TYPE (@00))
1758 || ((TYPE_PRECISION (TREE_TYPE (@00))
1759 >= TYPE_PRECISION (TREE_TYPE (@10)))
1760 && (TYPE_UNSIGNED (TREE_TYPE (@00))
1761 == TYPE_UNSIGNED (TREE_TYPE (@10))))
1762 || (TREE_CODE (@10) == INTEGER_CST
1763 && (TREE_CODE (TREE_TYPE (@00)) == INTEGER_TYPE
1764 || TREE_CODE (TREE_TYPE (@00)) == BOOLEAN_TYPE)
1765 && int_fits_type_p (@10, TREE_TYPE (@00)))))
1766 (cmp @00 (convert @10))
1767 (if (TREE_CODE (@10) == INTEGER_CST
1768 && TREE_CODE (TREE_TYPE (@00)) == INTEGER_TYPE
1769 && !int_fits_type_p (@10, TREE_TYPE (@00)))
1770 (with
1771 {
1772 tree min = lower_bound_in_type (TREE_TYPE (@10), TREE_TYPE (@00));
1773 tree max = upper_bound_in_type (TREE_TYPE (@10), TREE_TYPE (@00));
1774 bool above = integer_nonzerop (const_binop (LT_EXPR, type, max, @10));
1775 bool below = integer_nonzerop (const_binop (LT_EXPR, type, @10, min));
1776 }
1777 (if (above || below)
1778 (if (cmp == EQ_EXPR || cmp == NE_EXPR)
1779 { constant_boolean_node (cmp == EQ_EXPR ? false : true, type); }
1780 (if (cmp == LT_EXPR || cmp == LE_EXPR)
1781 { constant_boolean_node (above ? true : false, type); }
1782 (if (cmp == GT_EXPR || cmp == GE_EXPR)
1783 { constant_boolean_node (above ? false : true, type); }))))))))))))
1784
1785 (for cmp (eq ne)
1786 /* A local variable can never be pointed to by
1787 the default SSA name of an incoming parameter.
1788 SSA names are canonicalized to 2nd place. */
1789 (simplify
1790 (cmp addr@0 SSA_NAME@1)
1791 (if (SSA_NAME_IS_DEFAULT_DEF (@1)
1792 && TREE_CODE (SSA_NAME_VAR (@1)) == PARM_DECL)
1793 (with { tree base = get_base_address (TREE_OPERAND (@0, 0)); }
1794 (if (TREE_CODE (base) == VAR_DECL
1795 && auto_var_in_fn_p (base, current_function_decl))
1796 (if (cmp == NE_EXPR)
1797 { constant_boolean_node (true, type); }
1798 { constant_boolean_node (false, type); }))))))
1799
1800 /* Equality compare simplifications from fold_binary */
1801 (for cmp (eq ne)
1802
1803 /* If we have (A | C) == D where C & ~D != 0, convert this into 0.
1804 Similarly for NE_EXPR. */
1805 (simplify
1806 (cmp (convert?@3 (bit_ior @0 INTEGER_CST@1)) INTEGER_CST@2)
1807 (if (tree_nop_conversion_p (TREE_TYPE (@3), TREE_TYPE (@0))
1808 && wi::bit_and_not (@1, @2) != 0)
1809 { constant_boolean_node (cmp == NE_EXPR, type); }))
1810
1811 /* (X ^ Y) == 0 becomes X == Y, and (X ^ Y) != 0 becomes X != Y. */
1812 (simplify
1813 (cmp (bit_xor @0 @1) integer_zerop)
1814 (cmp @0 @1))
1815
1816 /* (X ^ Y) == Y becomes X == 0.
1817 Likewise (X ^ Y) == X becomes Y == 0. */
1818 (simplify
1819 (cmp:c (bit_xor:c @0 @1) @0)
1820 (cmp @1 { build_zero_cst (TREE_TYPE (@1)); }))
1821
1822 /* (X ^ C1) op C2 can be rewritten as X op (C1 ^ C2). */
1823 (simplify
1824 (cmp (convert?@3 (bit_xor @0 INTEGER_CST@1)) INTEGER_CST@2)
1825 (if (tree_nop_conversion_p (TREE_TYPE (@3), TREE_TYPE (@0)))
1826 (cmp @0 (bit_xor @1 (convert @2)))))
1827
1828 (simplify
1829 (cmp (convert? addr@0) integer_zerop)
1830 (if (tree_single_nonzero_warnv_p (@0, NULL))
1831 { constant_boolean_node (cmp == NE_EXPR, type); })))
1832
1833 /* When the addresses are not directly of decls compare base and offset.
1834 This implements some remaining parts of fold_comparison address
1835 comparisons but still no complete part of it. Still it is good
1836 enough to make fold_stmt not regress when not dispatching to fold_binary. */
1837 (for cmp (simple_comparison)
1838 (simplify
1839 (cmp (convert1?@2 addr@0) (convert2? addr@1))
1840 (with
1841 {
1842 HOST_WIDE_INT off0, off1;
1843 tree base0 = get_addr_base_and_unit_offset (TREE_OPERAND (@0, 0), &off0);
1844 tree base1 = get_addr_base_and_unit_offset (TREE_OPERAND (@1, 0), &off1);
1845 if (base0 && TREE_CODE (base0) == MEM_REF)
1846 {
1847 off0 += mem_ref_offset (base0).to_short_addr ();
1848 base0 = TREE_OPERAND (base0, 0);
1849 }
1850 if (base1 && TREE_CODE (base1) == MEM_REF)
1851 {
1852 off1 += mem_ref_offset (base1).to_short_addr ();
1853 base1 = TREE_OPERAND (base1, 0);
1854 }
1855 }
1856 (if (base0 && base1)
1857 (with
1858 {
1859 int equal = 2;
1860 if (decl_in_symtab_p (base0)
1861 && decl_in_symtab_p (base1))
1862 equal = symtab_node::get_create (base0)
1863 ->equal_address_to (symtab_node::get_create (base1));
1864 else if ((DECL_P (base0) || TREE_CODE (base0) == SSA_NAME)
1865 && (DECL_P (base1) || TREE_CODE (base1) == SSA_NAME))
1866 equal = (base0 == base1);
1867 }
1868 (if (equal == 1
1869 && (cmp == EQ_EXPR || cmp == NE_EXPR
1870 /* If the offsets are equal we can ignore overflow. */
1871 || off0 == off1
1872 || POINTER_TYPE_OVERFLOW_UNDEFINED
1873 /* Or if we compare using pointers to decls. */
1874 || (POINTER_TYPE_P (TREE_TYPE (@2))
1875 && DECL_P (base0))))
1876 (switch
1877 (if (cmp == EQ_EXPR)
1878 { constant_boolean_node (off0 == off1, type); })
1879 (if (cmp == NE_EXPR)
1880 { constant_boolean_node (off0 != off1, type); })
1881 (if (cmp == LT_EXPR)
1882 { constant_boolean_node (off0 < off1, type); })
1883 (if (cmp == LE_EXPR)
1884 { constant_boolean_node (off0 <= off1, type); })
1885 (if (cmp == GE_EXPR)
1886 { constant_boolean_node (off0 >= off1, type); })
1887 (if (cmp == GT_EXPR)
1888 { constant_boolean_node (off0 > off1, type); }))
1889 (if (equal == 0
1890 && DECL_P (base0) && DECL_P (base1)
1891 /* If we compare this as integers require equal offset. */
1892 && (!INTEGRAL_TYPE_P (TREE_TYPE (@2))
1893 || off0 == off1))
1894 (switch
1895 (if (cmp == EQ_EXPR)
1896 { constant_boolean_node (false, type); })
1897 (if (cmp == NE_EXPR)
1898 { constant_boolean_node (true, type); })))))))))
1899
1900 /* Non-equality compare simplifications from fold_binary */
1901 (for cmp (lt gt le ge)
1902 /* Comparisons with the highest or lowest possible integer of
1903 the specified precision will have known values. */
1904 (simplify
1905 (cmp (convert?@2 @0) INTEGER_CST@1)
1906 (if ((INTEGRAL_TYPE_P (TREE_TYPE (@1)) || POINTER_TYPE_P (TREE_TYPE (@1)))
1907 && tree_nop_conversion_p (TREE_TYPE (@2), TREE_TYPE (@0)))
1908 (with
1909 {
1910 tree arg1_type = TREE_TYPE (@1);
1911 unsigned int prec = TYPE_PRECISION (arg1_type);
1912 wide_int max = wi::max_value (arg1_type);
1913 wide_int signed_max = wi::max_value (prec, SIGNED);
1914 wide_int min = wi::min_value (arg1_type);
1915 }
1916 (switch
1917 (if (wi::eq_p (@1, max))
1918 (switch
1919 (if (cmp == GT_EXPR)
1920 { constant_boolean_node (false, type); })
1921 (if (cmp == GE_EXPR)
1922 (eq @2 @1))
1923 (if (cmp == LE_EXPR)
1924 { constant_boolean_node (true, type); })
1925 (if (cmp == LT_EXPR)
1926 (ne @2 @1))))
1927 (if (wi::eq_p (@1, min))
1928 (switch
1929 (if (cmp == LT_EXPR)
1930 { constant_boolean_node (false, type); })
1931 (if (cmp == LE_EXPR)
1932 (eq @2 @1))
1933 (if (cmp == GE_EXPR)
1934 { constant_boolean_node (true, type); })
1935 (if (cmp == GT_EXPR)
1936 (ne @2 @1))))
1937 (if (wi::eq_p (@1, max - 1))
1938 (switch
1939 (if (cmp == GT_EXPR)
1940 (eq @2 { wide_int_to_tree (TREE_TYPE (@1), wi::add (@1, 1)); }))
1941 (if (cmp == LE_EXPR)
1942 (ne @2 { wide_int_to_tree (TREE_TYPE (@1), wi::add (@1, 1)); }))))
1943 (if (wi::eq_p (@1, min + 1))
1944 (switch
1945 (if (cmp == GE_EXPR)
1946 (ne @2 { wide_int_to_tree (TREE_TYPE (@1), wi::sub (@1, 1)); }))
1947 (if (cmp == LT_EXPR)
1948 (eq @2 { wide_int_to_tree (TREE_TYPE (@1), wi::sub (@1, 1)); }))))
1949 (if (wi::eq_p (@1, signed_max)
1950 && TYPE_UNSIGNED (arg1_type)
1951 /* We will flip the signedness of the comparison operator
1952 associated with the mode of @1, so the sign bit is
1953 specified by this mode. Check that @1 is the signed
1954 max associated with this sign bit. */
1955 && prec == GET_MODE_PRECISION (TYPE_MODE (arg1_type))
1956 /* signed_type does not work on pointer types. */
1957 && INTEGRAL_TYPE_P (arg1_type))
1958 /* The following case also applies to X < signed_max+1
1959 and X >= signed_max+1 because previous transformations. */
1960 (if (cmp == LE_EXPR || cmp == GT_EXPR)
1961 (with { tree st = signed_type_for (arg1_type); }
1962 (if (cmp == LE_EXPR)
1963 (ge (convert:st @0) { build_zero_cst (st); })
1964 (lt (convert:st @0) { build_zero_cst (st); }))))))))))
1965
1966 (for cmp (unordered ordered unlt unle ungt unge uneq ltgt)
1967 /* If the second operand is NaN, the result is constant. */
1968 (simplify
1969 (cmp @0 REAL_CST@1)
1970 (if (REAL_VALUE_ISNAN (TREE_REAL_CST (@1))
1971 && (cmp != LTGT_EXPR || ! flag_trapping_math))
1972 { constant_boolean_node (cmp == ORDERED_EXPR || cmp == LTGT_EXPR
1973 ? false : true, type); })))
1974
1975 /* bool_var != 0 becomes bool_var. */
1976 (simplify
1977 (ne @0 integer_zerop)
1978 (if (TREE_CODE (TREE_TYPE (@0)) == BOOLEAN_TYPE
1979 && types_match (type, TREE_TYPE (@0)))
1980 (non_lvalue @0)))
1981 /* bool_var == 1 becomes bool_var. */
1982 (simplify
1983 (eq @0 integer_onep)
1984 (if (TREE_CODE (TREE_TYPE (@0)) == BOOLEAN_TYPE
1985 && types_match (type, TREE_TYPE (@0)))
1986 (non_lvalue @0)))
1987 /* Do not handle
1988 bool_var == 0 becomes !bool_var or
1989 bool_var != 1 becomes !bool_var
1990 here because that only is good in assignment context as long
1991 as we require a tcc_comparison in GIMPLE_CONDs where we'd
1992 replace if (x == 0) with tem = ~x; if (tem != 0) which is
1993 clearly less optimal and which we'll transform again in forwprop. */
1994
1995
1996 /* Simplification of math builtins. */
1997
1998 /* fold_builtin_logarithm */
1999 (if (flag_unsafe_math_optimizations)
2000 /* Special case, optimize logN(expN(x)) = x. */
2001 (for logs (LOG LOG2 LOG10)
2002 exps (EXP EXP2 EXP10)
2003 (simplify
2004 (logs (exps @0))
2005 @0))
2006 /* Optimize logN(func()) for various exponential functions. We
2007 want to determine the value "x" and the power "exponent" in
2008 order to transform logN(x**exponent) into exponent*logN(x). */
2009 (for logs (LOG LOG LOG LOG
2010 LOG2 LOG2 LOG2 LOG2
2011 LOG10 LOG10 LOG10 LOG10)
2012 exps (EXP EXP2 EXP10 POW10)
2013 (simplify
2014 (logs (exps @0))
2015 (with {
2016 tree x;
2017 switch (exps)
2018 {
2019 CASE_FLT_FN (BUILT_IN_EXP):
2020 /* Prepare to do logN(exp(exponent) -> exponent*logN(e). */
2021 x = build_real (type, real_value_truncate (TYPE_MODE (type),
2022 dconst_e ()));
2023 break;
2024 CASE_FLT_FN (BUILT_IN_EXP2):
2025 /* Prepare to do logN(exp2(exponent) -> exponent*logN(2). */
2026 x = build_real (type, dconst2);
2027 break;
2028 CASE_FLT_FN (BUILT_IN_EXP10):
2029 CASE_FLT_FN (BUILT_IN_POW10):
2030 /* Prepare to do logN(exp10(exponent) -> exponent*logN(10). */
2031 {
2032 REAL_VALUE_TYPE dconst10;
2033 real_from_integer (&dconst10, VOIDmode, 10, SIGNED);
2034 x = build_real (type, dconst10);
2035 }
2036 break;
2037 default:
2038 gcc_unreachable ();
2039 }
2040 }
2041 (mult (logs { x; }) @0))))
2042 (for logs (LOG LOG
2043 LOG2 LOG2
2044 LOG10 LOG10)
2045 exps (SQRT CBRT)
2046 (simplify
2047 (logs (exps @0))
2048 (with {
2049 tree x;
2050 switch (exps)
2051 {
2052 CASE_FLT_FN (BUILT_IN_SQRT):
2053 /* Prepare to do logN(sqrt(x) -> 0.5*logN(x). */
2054 x = build_real (type, dconsthalf);
2055 break;
2056 CASE_FLT_FN (BUILT_IN_CBRT):
2057 /* Prepare to do logN(cbrt(x) -> (1/3)*logN(x). */
2058 x = build_real (type, real_value_truncate (TYPE_MODE (type),
2059 dconst_third ()));
2060 break;
2061 default:
2062 gcc_unreachable ();
2063 }
2064 }
2065 (mult { x; } (logs @0)))))
2066 /* logN(pow(x,exponent) -> exponent*logN(x). */
2067 (for logs (LOG LOG2 LOG10)
2068 pows (POW)
2069 (simplify
2070 (logs (pows @0 @1))
2071 (mult @1 (logs @0)))))
2072
2073 /* Narrowing of arithmetic and logical operations.
2074
2075 These are conceptually similar to the transformations performed for
2076 the C/C++ front-ends by shorten_binary_op and shorten_compare. Long
2077 term we want to move all that code out of the front-ends into here. */
2078
2079 /* If we have a narrowing conversion of an arithmetic operation where
2080 both operands are widening conversions from the same type as the outer
2081 narrowing conversion. Then convert the innermost operands to a suitable
2082 unsigned type (to avoid introducing undefined behaviour), perform the
2083 operation and convert the result to the desired type. */
2084 (for op (plus minus)
2085 (simplify
2086 (convert (op:s (convert@2 @0) (convert@3 @1)))
2087 (if (INTEGRAL_TYPE_P (type)
2088 /* We check for type compatibility between @0 and @1 below,
2089 so there's no need to check that @1/@3 are integral types. */
2090 && INTEGRAL_TYPE_P (TREE_TYPE (@0))
2091 && INTEGRAL_TYPE_P (TREE_TYPE (@2))
2092 /* The precision of the type of each operand must match the
2093 precision of the mode of each operand, similarly for the
2094 result. */
2095 && (TYPE_PRECISION (TREE_TYPE (@0))
2096 == GET_MODE_PRECISION (TYPE_MODE (TREE_TYPE (@0))))
2097 && (TYPE_PRECISION (TREE_TYPE (@1))
2098 == GET_MODE_PRECISION (TYPE_MODE (TREE_TYPE (@1))))
2099 && TYPE_PRECISION (type) == GET_MODE_PRECISION (TYPE_MODE (type))
2100 /* The inner conversion must be a widening conversion. */
2101 && TYPE_PRECISION (TREE_TYPE (@2)) > TYPE_PRECISION (TREE_TYPE (@0))
2102 && types_match (@0, @1)
2103 && types_match (@0, type))
2104 (if (TYPE_OVERFLOW_WRAPS (TREE_TYPE (@0)))
2105 (convert (op @0 @1))
2106 (with { tree utype = unsigned_type_for (TREE_TYPE (@0)); }
2107 (convert (op (convert:utype @0) (convert:utype @1))))))))
2108
2109 /* This is another case of narrowing, specifically when there's an outer
2110 BIT_AND_EXPR which masks off bits outside the type of the innermost
2111 operands. Like the previous case we have to convert the operands
2112 to unsigned types to avoid introducing undefined behaviour for the
2113 arithmetic operation. */
2114 (for op (minus plus)
2115 (simplify
2116 (bit_and (op:s (convert@2 @0) (convert@3 @1)) INTEGER_CST@4)
2117 (if (INTEGRAL_TYPE_P (type)
2118 /* We check for type compatibility between @0 and @1 below,
2119 so there's no need to check that @1/@3 are integral types. */
2120 && INTEGRAL_TYPE_P (TREE_TYPE (@0))
2121 && INTEGRAL_TYPE_P (TREE_TYPE (@2))
2122 /* The precision of the type of each operand must match the
2123 precision of the mode of each operand, similarly for the
2124 result. */
2125 && (TYPE_PRECISION (TREE_TYPE (@0))
2126 == GET_MODE_PRECISION (TYPE_MODE (TREE_TYPE (@0))))
2127 && (TYPE_PRECISION (TREE_TYPE (@1))
2128 == GET_MODE_PRECISION (TYPE_MODE (TREE_TYPE (@1))))
2129 && TYPE_PRECISION (type) == GET_MODE_PRECISION (TYPE_MODE (type))
2130 /* The inner conversion must be a widening conversion. */
2131 && TYPE_PRECISION (TREE_TYPE (@2)) > TYPE_PRECISION (TREE_TYPE (@0))
2132 && types_match (@0, @1)
2133 && (tree_int_cst_min_precision (@4, TYPE_SIGN (TREE_TYPE (@0)))
2134 <= TYPE_PRECISION (TREE_TYPE (@0)))
2135 && (TYPE_OVERFLOW_WRAPS (TREE_TYPE (@0))
2136 || tree_int_cst_sgn (@4) >= 0))
2137 (if (TYPE_OVERFLOW_WRAPS (TREE_TYPE (@0)))
2138 (with { tree ntype = TREE_TYPE (@0); }
2139 (convert (bit_and (op @0 @1) (convert:ntype @4))))
2140 (with { tree utype = unsigned_type_for (TREE_TYPE (@0)); }
2141 (convert (bit_and (op (convert:utype @0) (convert:utype @1))
2142 (convert:utype @4))))))))