re PR tree-optimization/66299 (more optimize opportunity)
[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
30 real_zerop real_onep real_minus_onep
31 CONSTANT_CLASS_P
32 tree_expr_nonnegative_p)
33
34 /* Operator lists. */
35 (define_operator_list tcc_comparison
36 lt le eq ne ge gt unordered ordered unlt unle ungt unge uneq ltgt)
37 (define_operator_list inverted_tcc_comparison
38 ge gt ne eq lt le ordered unordered ge gt le lt ltgt uneq)
39 (define_operator_list inverted_tcc_comparison_with_nans
40 unge ungt ne eq unlt unle ordered unordered ge gt le lt ltgt uneq)
41 (define_operator_list swapped_tcc_comparison
42 gt ge eq ne le lt unordered ordered ungt unge unlt unle uneq ltgt)
43
44
45 /* Simplifications of operations with one constant operand and
46 simplifications to constants or single values. */
47
48 (for op (plus pointer_plus minus bit_ior bit_xor)
49 (simplify
50 (op @0 integer_zerop)
51 (non_lvalue @0)))
52
53 /* 0 +p index -> (type)index */
54 (simplify
55 (pointer_plus integer_zerop @1)
56 (non_lvalue (convert @1)))
57
58 /* See if ARG1 is zero and X + ARG1 reduces to X.
59 Likewise if the operands are reversed. */
60 (simplify
61 (plus:c @0 real_zerop@1)
62 (if (fold_real_zero_addition_p (type, @1, 0))
63 (non_lvalue @0)))
64
65 /* See if ARG1 is zero and X - ARG1 reduces to X. */
66 (simplify
67 (minus @0 real_zerop@1)
68 (if (fold_real_zero_addition_p (type, @1, 1))
69 (non_lvalue @0)))
70
71 /* Simplify x - x.
72 This is unsafe for certain floats even in non-IEEE formats.
73 In IEEE, it is unsafe because it does wrong for NaNs.
74 Also note that operand_equal_p is always false if an operand
75 is volatile. */
76 (simplify
77 (minus @0 @0)
78 (if (!FLOAT_TYPE_P (type) || !HONOR_NANS (type))
79 { build_zero_cst (type); }))
80
81 (simplify
82 (mult @0 integer_zerop@1)
83 @1)
84
85 /* Maybe fold x * 0 to 0. The expressions aren't the same
86 when x is NaN, since x * 0 is also NaN. Nor are they the
87 same in modes with signed zeros, since multiplying a
88 negative value by 0 gives -0, not +0. */
89 (simplify
90 (mult @0 real_zerop@1)
91 (if (!HONOR_NANS (type) && !HONOR_SIGNED_ZEROS (element_mode (type)))
92 @1))
93
94 /* In IEEE floating point, x*1 is not equivalent to x for snans.
95 Likewise for complex arithmetic with signed zeros. */
96 (simplify
97 (mult @0 real_onep)
98 (if (!HONOR_SNANS (element_mode (type))
99 && (!HONOR_SIGNED_ZEROS (element_mode (type))
100 || !COMPLEX_FLOAT_TYPE_P (type)))
101 (non_lvalue @0)))
102
103 /* Transform x * -1.0 into -x. */
104 (simplify
105 (mult @0 real_minus_onep)
106 (if (!HONOR_SNANS (element_mode (type))
107 && (!HONOR_SIGNED_ZEROS (element_mode (type))
108 || !COMPLEX_FLOAT_TYPE_P (type)))
109 (negate @0)))
110
111 /* Make sure to preserve divisions by zero. This is the reason why
112 we don't simplify x / x to 1 or 0 / x to 0. */
113 (for op (mult trunc_div ceil_div floor_div round_div exact_div)
114 (simplify
115 (op @0 integer_onep)
116 (non_lvalue @0)))
117
118 /* X / -1 is -X. */
119 (for div (trunc_div ceil_div floor_div round_div exact_div)
120 (simplify
121 (div @0 integer_minus_onep@1)
122 (if (!TYPE_UNSIGNED (type))
123 (negate @0))))
124
125 /* For unsigned integral types, FLOOR_DIV_EXPR is the same as
126 TRUNC_DIV_EXPR. Rewrite into the latter in this case. */
127 (simplify
128 (floor_div @0 @1)
129 (if ((INTEGRAL_TYPE_P (type) || VECTOR_INTEGER_TYPE_P (type))
130 && TYPE_UNSIGNED (type))
131 (trunc_div @0 @1)))
132
133 /* Combine two successive divisions. Note that combining ceil_div
134 and floor_div is trickier and combining round_div even more so. */
135 (for div (trunc_div exact_div)
136 (simplify
137 (div (div @0 INTEGER_CST@1) INTEGER_CST@2)
138 (with {
139 bool overflow_p;
140 wide_int mul = wi::mul (@1, @2, TYPE_SIGN (type), &overflow_p);
141 }
142 (if (!overflow_p)
143 (div @0 { wide_int_to_tree (type, mul); }))
144 (if (overflow_p
145 && (TYPE_UNSIGNED (type)
146 || mul != wi::min_value (TYPE_PRECISION (type), SIGNED)))
147 { build_zero_cst (type); }))))
148
149 /* Optimize A / A to 1.0 if we don't care about
150 NaNs or Infinities. */
151 (simplify
152 (rdiv @0 @0)
153 (if (FLOAT_TYPE_P (type)
154 && ! HONOR_NANS (type)
155 && ! HONOR_INFINITIES (element_mode (type)))
156 { build_one_cst (type); }))
157
158 /* Optimize -A / A to -1.0 if we don't care about
159 NaNs or Infinities. */
160 (simplify
161 (rdiv:c @0 (negate @0))
162 (if (FLOAT_TYPE_P (type)
163 && ! HONOR_NANS (type)
164 && ! HONOR_INFINITIES (element_mode (type)))
165 { build_minus_one_cst (type); }))
166
167 /* In IEEE floating point, x/1 is not equivalent to x for snans. */
168 (simplify
169 (rdiv @0 real_onep)
170 (if (!HONOR_SNANS (element_mode (type)))
171 (non_lvalue @0)))
172
173 /* In IEEE floating point, x/-1 is not equivalent to -x for snans. */
174 (simplify
175 (rdiv @0 real_minus_onep)
176 (if (!HONOR_SNANS (element_mode (type)))
177 (negate @0)))
178
179 /* If ARG1 is a constant, we can convert this to a multiply by the
180 reciprocal. This does not have the same rounding properties,
181 so only do this if -freciprocal-math. We can actually
182 always safely do it if ARG1 is a power of two, but it's hard to
183 tell if it is or not in a portable manner. */
184 (for cst (REAL_CST COMPLEX_CST VECTOR_CST)
185 (simplify
186 (rdiv @0 cst@1)
187 (if (optimize)
188 (if (flag_reciprocal_math
189 && !real_zerop (@1))
190 (with
191 { tree tem = const_binop (RDIV_EXPR, type, build_one_cst (type), @1); }
192 (if (tem)
193 (mult @0 { tem; } ))))
194 (if (cst != COMPLEX_CST)
195 (with { tree inverse = exact_inverse (type, @1); }
196 (if (inverse)
197 (mult @0 { inverse; } )))))))
198
199 /* Same applies to modulo operations, but fold is inconsistent here
200 and simplifies 0 % x to 0, only preserving literal 0 % 0. */
201 (for mod (ceil_mod floor_mod round_mod trunc_mod)
202 /* 0 % X is always zero. */
203 (simplify
204 (mod integer_zerop@0 @1)
205 /* But not for 0 % 0 so that we can get the proper warnings and errors. */
206 (if (!integer_zerop (@1))
207 @0))
208 /* X % 1 is always zero. */
209 (simplify
210 (mod @0 integer_onep)
211 { build_zero_cst (type); })
212 /* X % -1 is zero. */
213 (simplify
214 (mod @0 integer_minus_onep@1)
215 (if (!TYPE_UNSIGNED (type))
216 { build_zero_cst (type); }))
217 /* (X % Y) % Y is just X % Y. */
218 (simplify
219 (mod (mod@2 @0 @1) @1)
220 @2))
221
222 /* X % -C is the same as X % C. */
223 (simplify
224 (trunc_mod @0 INTEGER_CST@1)
225 (if (TYPE_SIGN (type) == SIGNED
226 && !TREE_OVERFLOW (@1)
227 && wi::neg_p (@1)
228 && !TYPE_OVERFLOW_TRAPS (type)
229 /* Avoid this transformation if C is INT_MIN, i.e. C == -C. */
230 && !sign_bit_p (@1, @1))
231 (trunc_mod @0 (negate @1))))
232
233 /* X % -Y is the same as X % Y. */
234 (simplify
235 (trunc_mod @0 (convert? (negate @1)))
236 (if (!TYPE_UNSIGNED (type)
237 && !TYPE_OVERFLOW_TRAPS (type)
238 && tree_nop_conversion_p (type, TREE_TYPE (@1)))
239 (trunc_mod @0 (convert @1))))
240
241 /* Optimize TRUNC_MOD_EXPR by a power of two into a BIT_AND_EXPR,
242 i.e. "X % C" into "X & (C - 1)", if X and C are positive.
243 Also optimize A % (C << N) where C is a power of 2,
244 to A & ((C << N) - 1). */
245 (match (power_of_two_cand @1)
246 INTEGER_CST@1)
247 (match (power_of_two_cand @1)
248 (lshift INTEGER_CST@1 @2))
249 (for mod (trunc_mod floor_mod)
250 (simplify
251 (mod @0 (convert?@3 (power_of_two_cand@1 @2)))
252 (if ((TYPE_UNSIGNED (type)
253 || tree_expr_nonnegative_p (@0))
254 && tree_nop_conversion_p (type, TREE_TYPE (@3))
255 && integer_pow2p (@2) && tree_int_cst_sgn (@2) > 0)
256 (bit_and @0 (convert (minus @1 { build_int_cst (TREE_TYPE (@1), 1); }))))))
257
258 /* X % Y is smaller than Y. */
259 (for cmp (lt ge)
260 (simplify
261 (cmp (trunc_mod @0 @1) @1)
262 (if (TYPE_UNSIGNED (TREE_TYPE (@0)))
263 { constant_boolean_node (cmp == LT_EXPR, type); })))
264 (for cmp (gt le)
265 (simplify
266 (cmp @1 (trunc_mod @0 @1))
267 (if (TYPE_UNSIGNED (TREE_TYPE (@0)))
268 { constant_boolean_node (cmp == GT_EXPR, type); })))
269
270 /* x | ~0 -> ~0 */
271 (simplify
272 (bit_ior @0 integer_all_onesp@1)
273 @1)
274
275 /* x & 0 -> 0 */
276 (simplify
277 (bit_and @0 integer_zerop@1)
278 @1)
279
280 /* x ^ x -> 0 */
281 (simplify
282 (bit_xor @0 @0)
283 { build_zero_cst (type); })
284
285 /* Canonicalize X ^ ~0 to ~X. */
286 (simplify
287 (bit_xor @0 integer_all_onesp@1)
288 (bit_not @0))
289
290 /* x & ~0 -> x */
291 (simplify
292 (bit_and @0 integer_all_onesp)
293 (non_lvalue @0))
294
295 /* x & x -> x, x | x -> x */
296 (for bitop (bit_and bit_ior)
297 (simplify
298 (bitop @0 @0)
299 (non_lvalue @0)))
300
301 /* x + (x & 1) -> (x + 1) & ~1 */
302 (simplify
303 (plus:c @0 (bit_and@2 @0 integer_onep@1))
304 (if (TREE_CODE (@2) != SSA_NAME || has_single_use (@2))
305 (bit_and (plus @0 @1) (bit_not @1))))
306
307 /* x & ~(x & y) -> x & ~y */
308 /* x | ~(x | y) -> x | ~y */
309 (for bitop (bit_and bit_ior)
310 (simplify
311 (bitop:c @0 (bit_not (bitop:c@2 @0 @1)))
312 (if (TREE_CODE (@2) != SSA_NAME || has_single_use (@2))
313 (bitop @0 (bit_not @1)))))
314
315 /* (x | y) & ~x -> y & ~x */
316 /* (x & y) | ~x -> y | ~x */
317 (for bitop (bit_and bit_ior)
318 rbitop (bit_ior bit_and)
319 (simplify
320 (bitop:c (rbitop:c @0 @1) (bit_not@2 @0))
321 (bitop @1 @2)))
322
323 (simplify
324 (abs (negate @0))
325 (abs @0))
326 (simplify
327 (abs tree_expr_nonnegative_p@0)
328 @0)
329
330
331 /* Try to fold (type) X op CST -> (type) (X op ((type-x) CST))
332 when profitable.
333 For bitwise binary operations apply operand conversions to the
334 binary operation result instead of to the operands. This allows
335 to combine successive conversions and bitwise binary operations.
336 We combine the above two cases by using a conditional convert. */
337 (for bitop (bit_and bit_ior bit_xor)
338 (simplify
339 (bitop (convert @0) (convert? @1))
340 (if (((TREE_CODE (@1) == INTEGER_CST
341 && INTEGRAL_TYPE_P (TREE_TYPE (@0))
342 && int_fits_type_p (@1, TREE_TYPE (@0)))
343 || types_match (@0, @1))
344 /* ??? This transform conflicts with fold-const.c doing
345 Convert (T)(x & c) into (T)x & (T)c, if c is an integer
346 constants (if x has signed type, the sign bit cannot be set
347 in c). This folds extension into the BIT_AND_EXPR.
348 Restrict it to GIMPLE to avoid endless recursions. */
349 && (bitop != BIT_AND_EXPR || GIMPLE)
350 && (/* That's a good idea if the conversion widens the operand, thus
351 after hoisting the conversion the operation will be narrower. */
352 TYPE_PRECISION (TREE_TYPE (@0)) < TYPE_PRECISION (type)
353 /* It's also a good idea if the conversion is to a non-integer
354 mode. */
355 || GET_MODE_CLASS (TYPE_MODE (type)) != MODE_INT
356 /* Or if the precision of TO is not the same as the precision
357 of its mode. */
358 || TYPE_PRECISION (type) != GET_MODE_PRECISION (TYPE_MODE (type))))
359 (convert (bitop @0 (convert @1))))))
360
361 /* Simplify (A & B) OP0 (C & B) to (A OP0 C) & B. */
362 (for bitop (bit_and bit_ior bit_xor)
363 (simplify
364 (bitop (bit_and:c @0 @1) (bit_and @2 @1))
365 (bit_and (bitop @0 @2) @1)))
366
367 /* (x | CST1) & CST2 -> (x & CST2) | (CST1 & CST2) */
368 (simplify
369 (bit_and (bit_ior @0 CONSTANT_CLASS_P@1) CONSTANT_CLASS_P@2)
370 (bit_ior (bit_and @0 @2) (bit_and @1 @2)))
371
372 /* Combine successive equal operations with constants. */
373 (for bitop (bit_and bit_ior bit_xor)
374 (simplify
375 (bitop (bitop @0 CONSTANT_CLASS_P@1) CONSTANT_CLASS_P@2)
376 (bitop @0 (bitop @1 @2))))
377
378 /* Try simple folding for X op !X, and X op X with the help
379 of the truth_valued_p and logical_inverted_value predicates. */
380 (match truth_valued_p
381 @0
382 (if (INTEGRAL_TYPE_P (type) && TYPE_PRECISION (type) == 1)))
383 (for op (tcc_comparison truth_and truth_andif truth_or truth_orif truth_xor)
384 (match truth_valued_p
385 (op @0 @1)))
386 (match truth_valued_p
387 (truth_not @0))
388
389 (match (logical_inverted_value @0)
390 (bit_not truth_valued_p@0))
391 (match (logical_inverted_value @0)
392 (eq @0 integer_zerop))
393 (match (logical_inverted_value @0)
394 (ne truth_valued_p@0 integer_truep))
395 (match (logical_inverted_value @0)
396 (bit_xor truth_valued_p@0 integer_truep))
397
398 /* X & !X -> 0. */
399 (simplify
400 (bit_and:c @0 (logical_inverted_value @0))
401 { build_zero_cst (type); })
402 /* X | !X and X ^ !X -> 1, , if X is truth-valued. */
403 (for op (bit_ior bit_xor)
404 (simplify
405 (op:c truth_valued_p@0 (logical_inverted_value @0))
406 { constant_boolean_node (true, type); }))
407
408 (for bitop (bit_and bit_ior)
409 rbitop (bit_ior bit_and)
410 /* (x | y) & x -> x */
411 /* (x & y) | x -> x */
412 (simplify
413 (bitop:c (rbitop:c @0 @1) @0)
414 @0)
415 /* (~x | y) & x -> x & y */
416 /* (~x & y) | x -> x | y */
417 (simplify
418 (bitop:c (rbitop:c (bit_not @0) @1) @0)
419 (bitop @0 @1)))
420
421 /* If arg1 and arg2 are booleans (or any single bit type)
422 then try to simplify:
423
424 (~X & Y) -> X < Y
425 (X & ~Y) -> Y < X
426 (~X | Y) -> X <= Y
427 (X | ~Y) -> Y <= X
428
429 But only do this if our result feeds into a comparison as
430 this transformation is not always a win, particularly on
431 targets with and-not instructions.
432 -> simplify_bitwise_binary_boolean */
433 (simplify
434 (ne (bit_and:c (bit_not @0) @1) integer_zerop)
435 (if (INTEGRAL_TYPE_P (TREE_TYPE (@1))
436 && TYPE_PRECISION (TREE_TYPE (@1)) == 1)
437 (lt @0 @1)))
438 (simplify
439 (ne (bit_ior:c (bit_not @0) @1) integer_zerop)
440 (if (INTEGRAL_TYPE_P (TREE_TYPE (@1))
441 && TYPE_PRECISION (TREE_TYPE (@1)) == 1)
442 (le @0 @1)))
443
444 /* ~~x -> x */
445 (simplify
446 (bit_not (bit_not @0))
447 @0)
448
449 /* (x & ~m) | (y & m) -> ((x ^ y) & m) ^ x */
450 (simplify
451 (bit_ior:c (bit_and:c@3 @0 (bit_not @2)) (bit_and:c@4 @1 @2))
452 (if ((TREE_CODE (@3) != SSA_NAME || has_single_use (@3))
453 && (TREE_CODE (@4) != SSA_NAME || has_single_use (@4)))
454 (bit_xor (bit_and (bit_xor @0 @1) @2) @0)))
455
456
457 /* Associate (p +p off1) +p off2 as (p +p (off1 + off2)). */
458 (simplify
459 (pointer_plus (pointer_plus@2 @0 @1) @3)
460 (if (TREE_CODE (@2) != SSA_NAME || has_single_use (@2))
461 (pointer_plus @0 (plus @1 @3))))
462
463 /* Pattern match
464 tem1 = (long) ptr1;
465 tem2 = (long) ptr2;
466 tem3 = tem2 - tem1;
467 tem4 = (unsigned long) tem3;
468 tem5 = ptr1 + tem4;
469 and produce
470 tem5 = ptr2; */
471 (simplify
472 (pointer_plus @0 (convert?@2 (minus@3 (convert @1) (convert @0))))
473 /* Conditionally look through a sign-changing conversion. */
474 (if (TYPE_PRECISION (TREE_TYPE (@2)) == TYPE_PRECISION (TREE_TYPE (@3))
475 && ((GIMPLE && useless_type_conversion_p (type, TREE_TYPE (@1)))
476 || (GENERIC && type == TREE_TYPE (@1))))
477 @1))
478
479 /* Pattern match
480 tem = (sizetype) ptr;
481 tem = tem & algn;
482 tem = -tem;
483 ... = ptr p+ tem;
484 and produce the simpler and easier to analyze with respect to alignment
485 ... = ptr & ~algn; */
486 (simplify
487 (pointer_plus @0 (negate (bit_and (convert @0) INTEGER_CST@1)))
488 (with { tree algn = wide_int_to_tree (TREE_TYPE (@0), wi::bit_not (@1)); }
489 (bit_and @0 { algn; })))
490
491
492 /* We can't reassociate at all for saturating types. */
493 (if (!TYPE_SATURATING (type))
494
495 /* Contract negates. */
496 /* A + (-B) -> A - B */
497 (simplify
498 (plus:c (convert1? @0) (convert2? (negate @1)))
499 /* Apply STRIP_NOPS on @0 and the negate. */
500 (if (tree_nop_conversion_p (type, TREE_TYPE (@0))
501 && tree_nop_conversion_p (type, TREE_TYPE (@1))
502 && !TYPE_OVERFLOW_SANITIZED (type))
503 (minus (convert @0) (convert @1))))
504 /* A - (-B) -> A + B */
505 (simplify
506 (minus (convert1? @0) (convert2? (negate @1)))
507 (if (tree_nop_conversion_p (type, TREE_TYPE (@0))
508 && tree_nop_conversion_p (type, TREE_TYPE (@1))
509 && !TYPE_OVERFLOW_SANITIZED (type))
510 (plus (convert @0) (convert @1))))
511 /* -(-A) -> A */
512 (simplify
513 (negate (convert? (negate @1)))
514 (if (tree_nop_conversion_p (type, TREE_TYPE (@1))
515 && !TYPE_OVERFLOW_SANITIZED (type))
516 (convert @1)))
517
518 /* We can't reassociate floating-point or fixed-point plus or minus
519 because of saturation to +-Inf. */
520 (if (!FLOAT_TYPE_P (type) && !FIXED_POINT_TYPE_P (type))
521
522 /* Match patterns that allow contracting a plus-minus pair
523 irrespective of overflow issues. */
524 /* (A +- B) - A -> +- B */
525 /* (A +- B) -+ B -> A */
526 /* A - (A +- B) -> -+ B */
527 /* A +- (B -+ A) -> +- B */
528 (simplify
529 (minus (plus:c @0 @1) @0)
530 @1)
531 (simplify
532 (minus (minus @0 @1) @0)
533 (negate @1))
534 (simplify
535 (plus:c (minus @0 @1) @1)
536 @0)
537 (simplify
538 (minus @0 (plus:c @0 @1))
539 (negate @1))
540 (simplify
541 (minus @0 (minus @0 @1))
542 @1)
543
544 /* (A +- CST) +- CST -> A + CST */
545 (for outer_op (plus minus)
546 (for inner_op (plus minus)
547 (simplify
548 (outer_op (inner_op @0 CONSTANT_CLASS_P@1) CONSTANT_CLASS_P@2)
549 /* If the constant operation overflows we cannot do the transform
550 as we would introduce undefined overflow, for example
551 with (a - 1) + INT_MIN. */
552 (with { tree cst = fold_binary (outer_op == inner_op
553 ? PLUS_EXPR : MINUS_EXPR, type, @1, @2); }
554 (if (cst && !TREE_OVERFLOW (cst))
555 (inner_op @0 { cst; } ))))))
556
557 /* (CST - A) +- CST -> CST - A */
558 (for outer_op (plus minus)
559 (simplify
560 (outer_op (minus CONSTANT_CLASS_P@1 @0) CONSTANT_CLASS_P@2)
561 (with { tree cst = fold_binary (outer_op, type, @1, @2); }
562 (if (cst && !TREE_OVERFLOW (cst))
563 (minus { cst; } @0)))))
564
565 /* ~A + A -> -1 */
566 (simplify
567 (plus:c (bit_not @0) @0)
568 (if (!TYPE_OVERFLOW_TRAPS (type))
569 { build_all_ones_cst (type); }))
570
571 /* ~A + 1 -> -A */
572 (simplify
573 (plus (convert? (bit_not @0)) integer_each_onep)
574 (if (tree_nop_conversion_p (type, TREE_TYPE (@0)))
575 (negate (convert @0))))
576
577 /* -A - 1 -> ~A */
578 (simplify
579 (minus (convert? (negate @0)) integer_each_onep)
580 (if (!TYPE_OVERFLOW_TRAPS (type)
581 && tree_nop_conversion_p (type, TREE_TYPE (@0)))
582 (bit_not (convert @0))))
583
584 /* -1 - A -> ~A */
585 (simplify
586 (minus integer_all_onesp @0)
587 (bit_not @0))
588
589 /* (T)(P + A) - (T)P -> (T) A */
590 (for add (plus pointer_plus)
591 (simplify
592 (minus (convert (add @0 @1))
593 (convert @0))
594 (if (element_precision (type) <= element_precision (TREE_TYPE (@1))
595 /* For integer types, if A has a smaller type
596 than T the result depends on the possible
597 overflow in P + A.
598 E.g. T=size_t, A=(unsigned)429497295, P>0.
599 However, if an overflow in P + A would cause
600 undefined behavior, we can assume that there
601 is no overflow. */
602 || (INTEGRAL_TYPE_P (TREE_TYPE (@0))
603 && TYPE_OVERFLOW_UNDEFINED (TREE_TYPE (@0)))
604 /* For pointer types, if the conversion of A to the
605 final type requires a sign- or zero-extension,
606 then we have to punt - it is not defined which
607 one is correct. */
608 || (POINTER_TYPE_P (TREE_TYPE (@0))
609 && TREE_CODE (@1) == INTEGER_CST
610 && tree_int_cst_sign_bit (@1) == 0))
611 (convert @1))))))
612
613
614 /* Simplifications of MIN_EXPR and MAX_EXPR. */
615
616 (for minmax (min max)
617 (simplify
618 (minmax @0 @0)
619 @0))
620 (simplify
621 (min @0 @1)
622 (if (INTEGRAL_TYPE_P (type)
623 && TYPE_MIN_VALUE (type)
624 && operand_equal_p (@1, TYPE_MIN_VALUE (type), OEP_ONLY_CONST))
625 @1))
626 (simplify
627 (max @0 @1)
628 (if (INTEGRAL_TYPE_P (type)
629 && TYPE_MAX_VALUE (type)
630 && operand_equal_p (@1, TYPE_MAX_VALUE (type), OEP_ONLY_CONST))
631 @1))
632
633
634 /* Simplifications of shift and rotates. */
635
636 (for rotate (lrotate rrotate)
637 (simplify
638 (rotate integer_all_onesp@0 @1)
639 @0))
640
641 /* Optimize -1 >> x for arithmetic right shifts. */
642 (simplify
643 (rshift integer_all_onesp@0 @1)
644 (if (!TYPE_UNSIGNED (type)
645 && tree_expr_nonnegative_p (@1))
646 @0))
647
648 (for shiftrotate (lrotate rrotate lshift rshift)
649 (simplify
650 (shiftrotate @0 integer_zerop)
651 (non_lvalue @0))
652 (simplify
653 (shiftrotate integer_zerop@0 @1)
654 @0)
655 /* Prefer vector1 << scalar to vector1 << vector2
656 if vector2 is uniform. */
657 (for vec (VECTOR_CST CONSTRUCTOR)
658 (simplify
659 (shiftrotate @0 vec@1)
660 (with { tree tem = uniform_vector_p (@1); }
661 (if (tem)
662 (shiftrotate @0 { tem; }))))))
663
664 /* Rewrite an LROTATE_EXPR by a constant into an
665 RROTATE_EXPR by a new constant. */
666 (simplify
667 (lrotate @0 INTEGER_CST@1)
668 (rrotate @0 { fold_binary (MINUS_EXPR, TREE_TYPE (@1),
669 build_int_cst (TREE_TYPE (@1),
670 element_precision (type)), @1); }))
671
672 /* ((1 << A) & 1) != 0 -> A == 0
673 ((1 << A) & 1) == 0 -> A != 0 */
674 (for cmp (ne eq)
675 icmp (eq ne)
676 (simplify
677 (cmp (bit_and (lshift integer_onep @0) integer_onep) integer_zerop)
678 (icmp @0 { build_zero_cst (TREE_TYPE (@0)); })))
679
680 /* (CST1 << A) == CST2 -> A == ctz (CST2) - ctz (CST1)
681 (CST1 << A) != CST2 -> A != ctz (CST2) - ctz (CST1)
682 if CST2 != 0. */
683 (for cmp (ne eq)
684 (simplify
685 (cmp (lshift INTEGER_CST@0 @1) INTEGER_CST@2)
686 (with { int cand = wi::ctz (@2) - wi::ctz (@0); }
687 (if (cand < 0
688 || (!integer_zerop (@2)
689 && wi::ne_p (wi::lshift (@0, cand), @2)))
690 { constant_boolean_node (cmp == NE_EXPR, type); })
691 (if (!integer_zerop (@2)
692 && wi::eq_p (wi::lshift (@0, cand), @2))
693 (cmp @1 { build_int_cst (TREE_TYPE (@1), cand); })))))
694
695 /* Simplifications of conversions. */
696
697 /* Basic strip-useless-type-conversions / strip_nops. */
698 (for cvt (convert view_convert float fix_trunc)
699 (simplify
700 (cvt @0)
701 (if ((GIMPLE && useless_type_conversion_p (type, TREE_TYPE (@0)))
702 || (GENERIC && type == TREE_TYPE (@0)))
703 @0)))
704
705 /* Contract view-conversions. */
706 (simplify
707 (view_convert (view_convert @0))
708 (view_convert @0))
709
710 /* For integral conversions with the same precision or pointer
711 conversions use a NOP_EXPR instead. */
712 (simplify
713 (view_convert @0)
714 (if ((INTEGRAL_TYPE_P (type) || POINTER_TYPE_P (type))
715 && (INTEGRAL_TYPE_P (TREE_TYPE (@0)) || POINTER_TYPE_P (TREE_TYPE (@0)))
716 && TYPE_PRECISION (type) == TYPE_PRECISION (TREE_TYPE (@0)))
717 (convert @0)))
718
719 /* Strip inner integral conversions that do not change precision or size. */
720 (simplify
721 (view_convert (convert@0 @1))
722 (if ((INTEGRAL_TYPE_P (TREE_TYPE (@0)) || POINTER_TYPE_P (TREE_TYPE (@0)))
723 && (INTEGRAL_TYPE_P (TREE_TYPE (@1)) || POINTER_TYPE_P (TREE_TYPE (@1)))
724 && (TYPE_PRECISION (TREE_TYPE (@0)) == TYPE_PRECISION (TREE_TYPE (@1)))
725 && (TYPE_SIZE (TREE_TYPE (@0)) == TYPE_SIZE (TREE_TYPE (@1))))
726 (view_convert @1)))
727
728 /* Re-association barriers around constants and other re-association
729 barriers can be removed. */
730 (simplify
731 (paren CONSTANT_CLASS_P@0)
732 @0)
733 (simplify
734 (paren (paren@1 @0))
735 @1)
736
737 /* Handle cases of two conversions in a row. */
738 (for ocvt (convert float fix_trunc)
739 (for icvt (convert float)
740 (simplify
741 (ocvt (icvt@1 @0))
742 (with
743 {
744 tree inside_type = TREE_TYPE (@0);
745 tree inter_type = TREE_TYPE (@1);
746 int inside_int = INTEGRAL_TYPE_P (inside_type);
747 int inside_ptr = POINTER_TYPE_P (inside_type);
748 int inside_float = FLOAT_TYPE_P (inside_type);
749 int inside_vec = VECTOR_TYPE_P (inside_type);
750 unsigned int inside_prec = TYPE_PRECISION (inside_type);
751 int inside_unsignedp = TYPE_UNSIGNED (inside_type);
752 int inter_int = INTEGRAL_TYPE_P (inter_type);
753 int inter_ptr = POINTER_TYPE_P (inter_type);
754 int inter_float = FLOAT_TYPE_P (inter_type);
755 int inter_vec = VECTOR_TYPE_P (inter_type);
756 unsigned int inter_prec = TYPE_PRECISION (inter_type);
757 int inter_unsignedp = TYPE_UNSIGNED (inter_type);
758 int final_int = INTEGRAL_TYPE_P (type);
759 int final_ptr = POINTER_TYPE_P (type);
760 int final_float = FLOAT_TYPE_P (type);
761 int final_vec = VECTOR_TYPE_P (type);
762 unsigned int final_prec = TYPE_PRECISION (type);
763 int final_unsignedp = TYPE_UNSIGNED (type);
764 }
765 /* In addition to the cases of two conversions in a row
766 handled below, if we are converting something to its own
767 type via an object of identical or wider precision, neither
768 conversion is needed. */
769 (if (((GIMPLE && useless_type_conversion_p (type, inside_type))
770 || (GENERIC
771 && TYPE_MAIN_VARIANT (type) == TYPE_MAIN_VARIANT (inside_type)))
772 && (((inter_int || inter_ptr) && final_int)
773 || (inter_float && final_float))
774 && inter_prec >= final_prec)
775 (ocvt @0))
776
777 /* Likewise, if the intermediate and initial types are either both
778 float or both integer, we don't need the middle conversion if the
779 former is wider than the latter and doesn't change the signedness
780 (for integers). Avoid this if the final type is a pointer since
781 then we sometimes need the middle conversion. Likewise if the
782 final type has a precision not equal to the size of its mode. */
783 (if (((inter_int && inside_int) || (inter_float && inside_float))
784 && (final_int || final_float)
785 && inter_prec >= inside_prec
786 && (inter_float || inter_unsignedp == inside_unsignedp)
787 && ! (final_prec != GET_MODE_PRECISION (TYPE_MODE (type))
788 && TYPE_MODE (type) == TYPE_MODE (inter_type)))
789 (ocvt @0))
790
791 /* If we have a sign-extension of a zero-extended value, we can
792 replace that by a single zero-extension. Likewise if the
793 final conversion does not change precision we can drop the
794 intermediate conversion. */
795 (if (inside_int && inter_int && final_int
796 && ((inside_prec < inter_prec && inter_prec < final_prec
797 && inside_unsignedp && !inter_unsignedp)
798 || final_prec == inter_prec))
799 (ocvt @0))
800
801 /* Two conversions in a row are not needed unless:
802 - some conversion is floating-point (overstrict for now), or
803 - some conversion is a vector (overstrict for now), or
804 - the intermediate type is narrower than both initial and
805 final, or
806 - the intermediate type and innermost type differ in signedness,
807 and the outermost type is wider than the intermediate, or
808 - the initial type is a pointer type and the precisions of the
809 intermediate and final types differ, or
810 - the final type is a pointer type and the precisions of the
811 initial and intermediate types differ. */
812 (if (! inside_float && ! inter_float && ! final_float
813 && ! inside_vec && ! inter_vec && ! final_vec
814 && (inter_prec >= inside_prec || inter_prec >= final_prec)
815 && ! (inside_int && inter_int
816 && inter_unsignedp != inside_unsignedp
817 && inter_prec < final_prec)
818 && ((inter_unsignedp && inter_prec > inside_prec)
819 == (final_unsignedp && final_prec > inter_prec))
820 && ! (inside_ptr && inter_prec != final_prec)
821 && ! (final_ptr && inside_prec != inter_prec)
822 && ! (final_prec != GET_MODE_PRECISION (TYPE_MODE (type))
823 && TYPE_MODE (type) == TYPE_MODE (inter_type)))
824 (ocvt @0))
825
826 /* A truncation to an unsigned type (a zero-extension) should be
827 canonicalized as bitwise and of a mask. */
828 (if (final_int && inter_int && inside_int
829 && final_prec == inside_prec
830 && final_prec > inter_prec
831 && inter_unsignedp)
832 (convert (bit_and @0 { wide_int_to_tree
833 (inside_type,
834 wi::mask (inter_prec, false,
835 TYPE_PRECISION (inside_type))); })))
836
837 /* If we are converting an integer to a floating-point that can
838 represent it exactly and back to an integer, we can skip the
839 floating-point conversion. */
840 (if (GIMPLE /* PR66211 */
841 && inside_int && inter_float && final_int &&
842 (unsigned) significand_size (TYPE_MODE (inter_type))
843 >= inside_prec - !inside_unsignedp)
844 (convert @0))))))
845
846 /* If we have a narrowing conversion to an integral type that is fed by a
847 BIT_AND_EXPR, we might be able to remove the BIT_AND_EXPR if it merely
848 masks off bits outside the final type (and nothing else). */
849 (simplify
850 (convert (bit_and @0 INTEGER_CST@1))
851 (if (INTEGRAL_TYPE_P (type)
852 && INTEGRAL_TYPE_P (TREE_TYPE (@0))
853 && TYPE_PRECISION (type) <= TYPE_PRECISION (TREE_TYPE (@0))
854 && operand_equal_p (@1, build_low_bits_mask (TREE_TYPE (@1),
855 TYPE_PRECISION (type)), 0))
856 (convert @0)))
857
858
859 /* (X /[ex] A) * A -> X. */
860 (simplify
861 (mult (convert? (exact_div @0 @1)) @1)
862 /* Look through a sign-changing conversion. */
863 (convert @0))
864
865 /* Canonicalization of binary operations. */
866
867 /* Convert X + -C into X - C. */
868 (simplify
869 (plus @0 REAL_CST@1)
870 (if (REAL_VALUE_NEGATIVE (TREE_REAL_CST (@1)))
871 (with { tree tem = fold_unary (NEGATE_EXPR, type, @1); }
872 (if (!TREE_OVERFLOW (tem) || !flag_trapping_math)
873 (minus @0 { tem; })))))
874
875 /* Convert x+x into x*2.0. */
876 (simplify
877 (plus @0 @0)
878 (if (SCALAR_FLOAT_TYPE_P (type))
879 (mult @0 { build_real (type, dconst2); })))
880
881 (simplify
882 (minus integer_zerop @1)
883 (negate @1))
884
885 /* (ARG0 - ARG1) is the same as (-ARG1 + ARG0). So check whether
886 ARG0 is zero and X + ARG0 reduces to X, since that would mean
887 (-ARG1 + ARG0) reduces to -ARG1. */
888 (simplify
889 (minus real_zerop@0 @1)
890 (if (fold_real_zero_addition_p (type, @0, 0))
891 (negate @1)))
892
893 /* Transform x * -1 into -x. */
894 (simplify
895 (mult @0 integer_minus_onep)
896 (negate @0))
897
898 /* COMPLEX_EXPR and REALPART/IMAGPART_EXPR cancellations. */
899 (simplify
900 (complex (realpart @0) (imagpart @0))
901 @0)
902 (simplify
903 (realpart (complex @0 @1))
904 @0)
905 (simplify
906 (imagpart (complex @0 @1))
907 @1)
908
909
910 /* BSWAP simplifications, transforms checked by gcc.dg/builtin-bswap-8.c. */
911 (for bswap (BUILT_IN_BSWAP16 BUILT_IN_BSWAP32 BUILT_IN_BSWAP64)
912 (simplify
913 (bswap (bswap @0))
914 @0)
915 (simplify
916 (bswap (bit_not (bswap @0)))
917 (bit_not @0))
918 (for bitop (bit_xor bit_ior bit_and)
919 (simplify
920 (bswap (bitop:c (bswap @0) @1))
921 (bitop @0 (bswap @1)))))
922
923
924 /* Combine COND_EXPRs and VEC_COND_EXPRs. */
925
926 /* Simplify constant conditions.
927 Only optimize constant conditions when the selected branch
928 has the same type as the COND_EXPR. This avoids optimizing
929 away "c ? x : throw", where the throw has a void type.
930 Note that we cannot throw away the fold-const.c variant nor
931 this one as we depend on doing this transform before possibly
932 A ? B : B -> B triggers and the fold-const.c one can optimize
933 0 ? A : B to B even if A has side-effects. Something
934 genmatch cannot handle. */
935 (simplify
936 (cond INTEGER_CST@0 @1 @2)
937 (if (integer_zerop (@0)
938 && (!VOID_TYPE_P (TREE_TYPE (@2))
939 || VOID_TYPE_P (type)))
940 @2)
941 (if (!integer_zerop (@0)
942 && (!VOID_TYPE_P (TREE_TYPE (@1))
943 || VOID_TYPE_P (type)))
944 @1))
945 (simplify
946 (vec_cond VECTOR_CST@0 @1 @2)
947 (if (integer_all_onesp (@0))
948 @1)
949 (if (integer_zerop (@0))
950 @2))
951
952 (for cnd (cond vec_cond)
953 /* A ? B : (A ? X : C) -> A ? B : C. */
954 (simplify
955 (cnd @0 (cnd @0 @1 @2) @3)
956 (cnd @0 @1 @3))
957 (simplify
958 (cnd @0 @1 (cnd @0 @2 @3))
959 (cnd @0 @1 @3))
960
961 /* A ? B : B -> B. */
962 (simplify
963 (cnd @0 @1 @1)
964 @1)
965
966 /* !A ? B : C -> A ? C : B. */
967 (simplify
968 (cnd (logical_inverted_value truth_valued_p@0) @1 @2)
969 (cnd @0 @2 @1)))
970
971
972 /* Simplifications of comparisons. */
973
974 /* We can simplify a logical negation of a comparison to the
975 inverted comparison. As we cannot compute an expression
976 operator using invert_tree_comparison we have to simulate
977 that with expression code iteration. */
978 (for cmp (tcc_comparison)
979 icmp (inverted_tcc_comparison)
980 ncmp (inverted_tcc_comparison_with_nans)
981 /* Ideally we'd like to combine the following two patterns
982 and handle some more cases by using
983 (logical_inverted_value (cmp @0 @1))
984 here but for that genmatch would need to "inline" that.
985 For now implement what forward_propagate_comparison did. */
986 (simplify
987 (bit_not (cmp @0 @1))
988 (if (VECTOR_TYPE_P (type)
989 || (INTEGRAL_TYPE_P (type) && TYPE_PRECISION (type) == 1))
990 /* Comparison inversion may be impossible for trapping math,
991 invert_tree_comparison will tell us. But we can't use
992 a computed operator in the replacement tree thus we have
993 to play the trick below. */
994 (with { enum tree_code ic = invert_tree_comparison
995 (cmp, HONOR_NANS (@0)); }
996 (if (ic == icmp)
997 (icmp @0 @1))
998 (if (ic == ncmp)
999 (ncmp @0 @1)))))
1000 (simplify
1001 (bit_xor (cmp @0 @1) integer_truep)
1002 (with { enum tree_code ic = invert_tree_comparison
1003 (cmp, HONOR_NANS (@0)); }
1004 (if (ic == icmp)
1005 (icmp @0 @1))
1006 (if (ic == ncmp)
1007 (ncmp @0 @1)))))
1008
1009 /* Unordered tests if either argument is a NaN. */
1010 (simplify
1011 (bit_ior (unordered @0 @0) (unordered @1 @1))
1012 (if (types_match (@0, @1))
1013 (unordered @0 @1)))
1014 (simplify
1015 (bit_and (ordered @0 @0) (ordered @1 @1))
1016 (if (types_match (@0, @1))
1017 (ordered @0 @1)))
1018 (simplify
1019 (bit_ior:c (unordered @0 @0) (unordered:c@2 @0 @1))
1020 @2)
1021 (simplify
1022 (bit_and:c (ordered @0 @0) (ordered:c@2 @0 @1))
1023 @2)
1024
1025 /* -A CMP -B -> B CMP A. */
1026 (for cmp (tcc_comparison)
1027 scmp (swapped_tcc_comparison)
1028 (simplify
1029 (cmp (negate @0) (negate @1))
1030 (if (FLOAT_TYPE_P (TREE_TYPE (@0))
1031 || (ANY_INTEGRAL_TYPE_P (TREE_TYPE (@0))
1032 && TYPE_OVERFLOW_UNDEFINED (TREE_TYPE (@0))))
1033 (scmp @0 @1)))
1034 (simplify
1035 (cmp (negate @0) CONSTANT_CLASS_P@1)
1036 (if (FLOAT_TYPE_P (TREE_TYPE (@0))
1037 || (ANY_INTEGRAL_TYPE_P (TREE_TYPE (@0))
1038 && TYPE_OVERFLOW_UNDEFINED (TREE_TYPE (@0))))
1039 (with { tree tem = fold_unary (NEGATE_EXPR, TREE_TYPE (@0), @1); }
1040 (if (tem && !TREE_OVERFLOW (tem))
1041 (scmp @0 { tem; }))))))
1042
1043 /* Simplification of math builtins. */
1044
1045 (define_operator_list LOG BUILT_IN_LOGF BUILT_IN_LOG BUILT_IN_LOGL)
1046 (define_operator_list EXP BUILT_IN_EXPF BUILT_IN_EXP BUILT_IN_EXPL)
1047 (define_operator_list LOG2 BUILT_IN_LOG2F BUILT_IN_LOG2 BUILT_IN_LOG2L)
1048 (define_operator_list EXP2 BUILT_IN_EXP2F BUILT_IN_EXP2 BUILT_IN_EXP2L)
1049 (define_operator_list LOG10 BUILT_IN_LOG10F BUILT_IN_LOG10 BUILT_IN_LOG10L)
1050 (define_operator_list EXP10 BUILT_IN_EXP10F BUILT_IN_EXP10 BUILT_IN_EXP10L)
1051 (define_operator_list POW BUILT_IN_POWF BUILT_IN_POW BUILT_IN_POWL)
1052 (define_operator_list POW10 BUILT_IN_POW10F BUILT_IN_POW10 BUILT_IN_POW10L)
1053 (define_operator_list SQRT BUILT_IN_SQRTF BUILT_IN_SQRT BUILT_IN_SQRTL)
1054 (define_operator_list CBRT BUILT_IN_CBRTF BUILT_IN_CBRT BUILT_IN_CBRTL)
1055
1056
1057 /* fold_builtin_logarithm */
1058 (if (flag_unsafe_math_optimizations)
1059 /* Special case, optimize logN(expN(x)) = x. */
1060 (for logs (LOG LOG2 LOG10)
1061 exps (EXP EXP2 EXP10)
1062 (simplify
1063 (logs (exps @0))
1064 @0))
1065 /* Optimize logN(func()) for various exponential functions. We
1066 want to determine the value "x" and the power "exponent" in
1067 order to transform logN(x**exponent) into exponent*logN(x). */
1068 (for logs (LOG LOG LOG LOG
1069 LOG2 LOG2 LOG2 LOG2
1070 LOG10 LOG10 LOG10 LOG10)
1071 exps (EXP EXP2 EXP10 POW10)
1072 (simplify
1073 (logs (exps @0))
1074 (with {
1075 tree x;
1076 switch (exps)
1077 {
1078 CASE_FLT_FN (BUILT_IN_EXP):
1079 /* Prepare to do logN(exp(exponent) -> exponent*logN(e). */
1080 x = build_real (type, real_value_truncate (TYPE_MODE (type),
1081 dconst_e ()));
1082 break;
1083 CASE_FLT_FN (BUILT_IN_EXP2):
1084 /* Prepare to do logN(exp2(exponent) -> exponent*logN(2). */
1085 x = build_real (type, dconst2);
1086 break;
1087 CASE_FLT_FN (BUILT_IN_EXP10):
1088 CASE_FLT_FN (BUILT_IN_POW10):
1089 /* Prepare to do logN(exp10(exponent) -> exponent*logN(10). */
1090 {
1091 REAL_VALUE_TYPE dconst10;
1092 real_from_integer (&dconst10, VOIDmode, 10, SIGNED);
1093 x = build_real (type, dconst10);
1094 }
1095 break;
1096 }
1097 }
1098 (mult (logs { x; }) @0))))
1099 (for logs (LOG LOG
1100 LOG2 LOG2
1101 LOG10 LOG10)
1102 exps (SQRT CBRT)
1103 (simplify
1104 (logs (exps @0))
1105 (with {
1106 tree x;
1107 switch (exps)
1108 {
1109 CASE_FLT_FN (BUILT_IN_SQRT):
1110 /* Prepare to do logN(sqrt(x) -> 0.5*logN(x). */
1111 x = build_real (type, dconsthalf);
1112 break;
1113 CASE_FLT_FN (BUILT_IN_CBRT):
1114 /* Prepare to do logN(cbrt(x) -> (1/3)*logN(x). */
1115 x = build_real (type, real_value_truncate (TYPE_MODE (type),
1116 dconst_third ()));
1117 break;
1118 }
1119 }
1120 (mult { x; } (logs @0)))))
1121 /* logN(pow(x,exponent) -> exponent*logN(x). */
1122 (for logs (LOG LOG2 LOG10)
1123 pows (POW)
1124 (simplify
1125 (logs (pows @0 @1))
1126 (mult @1 (logs @0)))))
1127
1128 /* Narrowing of arithmetic and logical operations.
1129
1130 These are conceptually similar to the transformations performed for
1131 the C/C++ front-ends by shorten_binary_op and shorten_compare. Long
1132 term we want to move all that code out of the front-ends into here. */
1133
1134 /* If we have a narrowing conversion of an arithmetic operation where
1135 both operands are widening conversions from the same type as the outer
1136 narrowing conversion. Then convert the innermost operands to a suitable
1137 unsigned type (to avoid introducing undefined behaviour), perform the
1138 operation and convert the result to the desired type. */
1139 (for op (plus minus)
1140 (simplify
1141 (convert (op@4 (convert@2 @0) (convert@3 @1)))
1142 (if (INTEGRAL_TYPE_P (type)
1143 /* We check for type compatibility between @0 and @1 below,
1144 so there's no need to check that @1/@3 are integral types. */
1145 && INTEGRAL_TYPE_P (TREE_TYPE (@0))
1146 && INTEGRAL_TYPE_P (TREE_TYPE (@2))
1147 /* The precision of the type of each operand must match the
1148 precision of the mode of each operand, similarly for the
1149 result. */
1150 && (TYPE_PRECISION (TREE_TYPE (@0))
1151 == GET_MODE_PRECISION (TYPE_MODE (TREE_TYPE (@0))))
1152 && (TYPE_PRECISION (TREE_TYPE (@1))
1153 == GET_MODE_PRECISION (TYPE_MODE (TREE_TYPE (@1))))
1154 && TYPE_PRECISION (type) == GET_MODE_PRECISION (TYPE_MODE (type))
1155 /* The inner conversion must be a widening conversion. */
1156 && TYPE_PRECISION (TREE_TYPE (@2)) > TYPE_PRECISION (TREE_TYPE (@0))
1157 && types_match (@0, @1)
1158 && types_match (@0, type)
1159 && single_use (@4))
1160 (if (TYPE_OVERFLOW_WRAPS (TREE_TYPE (@0)))
1161 (convert (op @0 @1)))
1162 (with { tree utype = unsigned_type_for (TREE_TYPE (@0)); }
1163 (convert (op (convert:utype @0) (convert:utype @1)))))))
1164
1165 /* This is another case of narrowing, specifically when there's an outer
1166 BIT_AND_EXPR which masks off bits outside the type of the innermost
1167 operands. Like the previous case we have to convert the operands
1168 to unsigned types to avoid introducing undefined behaviour for the
1169 arithmetic operation. */
1170 (for op (minus plus)
1171 (simplify
1172 (bit_and (op@5 (convert@2 @0) (convert@3 @1)) INTEGER_CST@4)
1173 (if (INTEGRAL_TYPE_P (type)
1174 /* We check for type compatibility between @0 and @1 below,
1175 so there's no need to check that @1/@3 are integral types. */
1176 && INTEGRAL_TYPE_P (TREE_TYPE (@0))
1177 && INTEGRAL_TYPE_P (TREE_TYPE (@2))
1178 /* The precision of the type of each operand must match the
1179 precision of the mode of each operand, similarly for the
1180 result. */
1181 && (TYPE_PRECISION (TREE_TYPE (@0))
1182 == GET_MODE_PRECISION (TYPE_MODE (TREE_TYPE (@0))))
1183 && (TYPE_PRECISION (TREE_TYPE (@1))
1184 == GET_MODE_PRECISION (TYPE_MODE (TREE_TYPE (@1))))
1185 && TYPE_PRECISION (type) == GET_MODE_PRECISION (TYPE_MODE (type))
1186 /* The inner conversion must be a widening conversion. */
1187 && TYPE_PRECISION (TREE_TYPE (@2)) > TYPE_PRECISION (TREE_TYPE (@0))
1188 && types_match (@0, @1)
1189 && (tree_int_cst_min_precision (@4, TYPE_SIGN (TREE_TYPE (@0)))
1190 <= TYPE_PRECISION (TREE_TYPE (@0)))
1191 && (TYPE_OVERFLOW_WRAPS (TREE_TYPE (@0))
1192 || tree_int_cst_sgn (@4) >= 0)
1193 && single_use (@5))
1194 (if (TYPE_OVERFLOW_WRAPS (TREE_TYPE (@0)))
1195 (with { tree ntype = TREE_TYPE (@0); }
1196 (convert (bit_and (op @0 @1) (convert:ntype @4)))))
1197 (with { tree utype = unsigned_type_for (TREE_TYPE (@0)); }
1198 (convert (bit_and (op (convert:utype @0) (convert:utype @1))
1199 (convert:utype @4)))))))
1200