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4ee9c684 | 1 | /* Conditional constant propagation pass for the GNU compiler. |
d353bf18 | 2 | Copyright (C) 2000-2015 Free Software Foundation, Inc. |
4ee9c684 | 3 | Adapted from original RTL SSA-CCP by Daniel Berlin <dberlin@dberlin.org> |
4 | Adapted to GIMPLE trees by Diego Novillo <dnovillo@redhat.com> | |
5 | ||
6 | This file is part of GCC. | |
48e1416a | 7 | |
4ee9c684 | 8 | GCC is free software; you can redistribute it and/or modify it |
9 | under the terms of the GNU General Public License as published by the | |
8c4c00c1 | 10 | Free Software Foundation; either version 3, or (at your option) any |
4ee9c684 | 11 | later version. |
48e1416a | 12 | |
4ee9c684 | 13 | GCC is distributed in the hope that it will be useful, but WITHOUT |
14 | ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or | |
15 | FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License | |
16 | for more details. | |
48e1416a | 17 | |
4ee9c684 | 18 | You should have received a copy of the GNU General Public License |
8c4c00c1 | 19 | along with GCC; see the file COPYING3. If not see |
20 | <http://www.gnu.org/licenses/>. */ | |
4ee9c684 | 21 | |
88dbf20f | 22 | /* Conditional constant propagation (CCP) is based on the SSA |
23 | propagation engine (tree-ssa-propagate.c). Constant assignments of | |
24 | the form VAR = CST are propagated from the assignments into uses of | |
25 | VAR, which in turn may generate new constants. The simulation uses | |
26 | a four level lattice to keep track of constant values associated | |
27 | with SSA names. Given an SSA name V_i, it may take one of the | |
28 | following values: | |
29 | ||
bfa30570 | 30 | UNINITIALIZED -> the initial state of the value. This value |
31 | is replaced with a correct initial value | |
32 | the first time the value is used, so the | |
33 | rest of the pass does not need to care about | |
34 | it. Using this value simplifies initialization | |
35 | of the pass, and prevents us from needlessly | |
36 | scanning statements that are never reached. | |
88dbf20f | 37 | |
38 | UNDEFINED -> V_i is a local variable whose definition | |
39 | has not been processed yet. Therefore we | |
40 | don't yet know if its value is a constant | |
41 | or not. | |
42 | ||
43 | CONSTANT -> V_i has been found to hold a constant | |
44 | value C. | |
45 | ||
46 | VARYING -> V_i cannot take a constant value, or if it | |
47 | does, it is not possible to determine it | |
48 | at compile time. | |
49 | ||
50 | The core of SSA-CCP is in ccp_visit_stmt and ccp_visit_phi_node: | |
51 | ||
52 | 1- In ccp_visit_stmt, we are interested in assignments whose RHS | |
53 | evaluates into a constant and conditional jumps whose predicate | |
54 | evaluates into a boolean true or false. When an assignment of | |
55 | the form V_i = CONST is found, V_i's lattice value is set to | |
56 | CONSTANT and CONST is associated with it. This causes the | |
57 | propagation engine to add all the SSA edges coming out the | |
58 | assignment into the worklists, so that statements that use V_i | |
59 | can be visited. | |
60 | ||
61 | If the statement is a conditional with a constant predicate, we | |
62 | mark the outgoing edges as executable or not executable | |
63 | depending on the predicate's value. This is then used when | |
64 | visiting PHI nodes to know when a PHI argument can be ignored. | |
48e1416a | 65 | |
88dbf20f | 66 | |
67 | 2- In ccp_visit_phi_node, if all the PHI arguments evaluate to the | |
68 | same constant C, then the LHS of the PHI is set to C. This | |
69 | evaluation is known as the "meet operation". Since one of the | |
70 | goals of this evaluation is to optimistically return constant | |
71 | values as often as possible, it uses two main short cuts: | |
72 | ||
73 | - If an argument is flowing in through a non-executable edge, it | |
74 | is ignored. This is useful in cases like this: | |
75 | ||
76 | if (PRED) | |
77 | a_9 = 3; | |
78 | else | |
79 | a_10 = 100; | |
80 | a_11 = PHI (a_9, a_10) | |
81 | ||
82 | If PRED is known to always evaluate to false, then we can | |
83 | assume that a_11 will always take its value from a_10, meaning | |
84 | that instead of consider it VARYING (a_9 and a_10 have | |
85 | different values), we can consider it CONSTANT 100. | |
86 | ||
87 | - If an argument has an UNDEFINED value, then it does not affect | |
88 | the outcome of the meet operation. If a variable V_i has an | |
89 | UNDEFINED value, it means that either its defining statement | |
90 | hasn't been visited yet or V_i has no defining statement, in | |
91 | which case the original symbol 'V' is being used | |
92 | uninitialized. Since 'V' is a local variable, the compiler | |
93 | may assume any initial value for it. | |
94 | ||
95 | ||
96 | After propagation, every variable V_i that ends up with a lattice | |
97 | value of CONSTANT will have the associated constant value in the | |
98 | array CONST_VAL[i].VALUE. That is fed into substitute_and_fold for | |
99 | final substitution and folding. | |
100 | ||
e913b5cd | 101 | This algorithm uses wide-ints at the max precision of the target. |
102 | This means that, with one uninteresting exception, variables with | |
103 | UNSIGNED types never go to VARYING because the bits above the | |
104 | precision of the type of the variable are always zero. The | |
105 | uninteresting case is a variable of UNSIGNED type that has the | |
106 | maximum precision of the target. Such variables can go to VARYING, | |
107 | but this causes no loss of infomation since these variables will | |
108 | never be extended. | |
109 | ||
4ee9c684 | 110 | References: |
111 | ||
112 | Constant propagation with conditional branches, | |
113 | Wegman and Zadeck, ACM TOPLAS 13(2):181-210. | |
114 | ||
115 | Building an Optimizing Compiler, | |
116 | Robert Morgan, Butterworth-Heinemann, 1998, Section 8.9. | |
117 | ||
118 | Advanced Compiler Design and Implementation, | |
119 | Steven Muchnick, Morgan Kaufmann, 1997, Section 12.6 */ | |
120 | ||
121 | #include "config.h" | |
122 | #include "system.h" | |
123 | #include "coretypes.h" | |
9ef16211 | 124 | #include "backend.h" |
4ee9c684 | 125 | #include "tree.h" |
9ef16211 | 126 | #include "gimple.h" |
127 | #include "hard-reg-set.h" | |
128 | #include "ssa.h" | |
129 | #include "alias.h" | |
b20a8bb4 | 130 | #include "fold-const.h" |
9ed99284 | 131 | #include "stor-layout.h" |
41511585 | 132 | #include "flags.h" |
4ee9c684 | 133 | #include "tm_p.h" |
ce084dfc | 134 | #include "gimple-pretty-print.h" |
bc61cadb | 135 | #include "internal-fn.h" |
136 | #include "gimple-fold.h" | |
137 | #include "tree-eh.h" | |
a8783bee | 138 | #include "gimplify.h" |
dcf1a1ec | 139 | #include "gimple-iterator.h" |
073c1fd5 | 140 | #include "tree-cfg.h" |
4ee9c684 | 141 | #include "tree-pass.h" |
41511585 | 142 | #include "tree-ssa-propagate.h" |
5a4b7e1e | 143 | #include "value-prof.h" |
41511585 | 144 | #include "langhooks.h" |
8782adcf | 145 | #include "target.h" |
0b205f4c | 146 | #include "diagnostic-core.h" |
43fb76c1 | 147 | #include "dbgcnt.h" |
9a65cc0a | 148 | #include "params.h" |
e913b5cd | 149 | #include "wide-int-print.h" |
f7715905 | 150 | #include "builtins.h" |
058a1b7a | 151 | #include "tree-chkp.h" |
4ee9c684 | 152 | |
2dc10fae | 153 | |
4ee9c684 | 154 | /* Possible lattice values. */ |
155 | typedef enum | |
156 | { | |
bfa30570 | 157 | UNINITIALIZED, |
4ee9c684 | 158 | UNDEFINED, |
159 | CONSTANT, | |
160 | VARYING | |
88dbf20f | 161 | } ccp_lattice_t; |
4ee9c684 | 162 | |
9908fe4d | 163 | struct ccp_prop_value_t { |
14f101cf | 164 | /* Lattice value. */ |
165 | ccp_lattice_t lattice_val; | |
166 | ||
167 | /* Propagated value. */ | |
168 | tree value; | |
b7e55469 | 169 | |
e913b5cd | 170 | /* Mask that applies to the propagated value during CCP. For X |
171 | with a CONSTANT lattice value X & ~mask == value & ~mask. The | |
172 | zero bits in the mask cover constant values. The ones mean no | |
173 | information. */ | |
5de9d3ed | 174 | widest_int mask; |
14f101cf | 175 | }; |
176 | ||
88dbf20f | 177 | /* Array of propagated constant values. After propagation, |
178 | CONST_VAL[I].VALUE holds the constant value for SSA_NAME(I). If | |
179 | the constant is held in an SSA name representing a memory store | |
4fb5e5ca | 180 | (i.e., a VDEF), CONST_VAL[I].MEM_REF will contain the actual |
181 | memory reference used to store (i.e., the LHS of the assignment | |
182 | doing the store). */ | |
9908fe4d | 183 | static ccp_prop_value_t *const_val; |
285df01b | 184 | static unsigned n_const_val; |
4ee9c684 | 185 | |
9908fe4d | 186 | static void canonicalize_value (ccp_prop_value_t *); |
6688f8ec | 187 | static bool ccp_fold_stmt (gimple_stmt_iterator *); |
27de3d43 | 188 | static void ccp_lattice_meet (ccp_prop_value_t *, ccp_prop_value_t *); |
4af351a8 | 189 | |
88dbf20f | 190 | /* Dump constant propagation value VAL to file OUTF prefixed by PREFIX. */ |
01406fc0 | 191 | |
192 | static void | |
9908fe4d | 193 | dump_lattice_value (FILE *outf, const char *prefix, ccp_prop_value_t val) |
01406fc0 | 194 | { |
41511585 | 195 | switch (val.lattice_val) |
01406fc0 | 196 | { |
88dbf20f | 197 | case UNINITIALIZED: |
198 | fprintf (outf, "%sUNINITIALIZED", prefix); | |
199 | break; | |
41511585 | 200 | case UNDEFINED: |
201 | fprintf (outf, "%sUNDEFINED", prefix); | |
202 | break; | |
203 | case VARYING: | |
204 | fprintf (outf, "%sVARYING", prefix); | |
205 | break; | |
41511585 | 206 | case CONSTANT: |
b7e55469 | 207 | if (TREE_CODE (val.value) != INTEGER_CST |
796b6678 | 208 | || val.mask == 0) |
16ab4e97 | 209 | { |
210 | fprintf (outf, "%sCONSTANT ", prefix); | |
211 | print_generic_expr (outf, val.value, dump_flags); | |
212 | } | |
b7e55469 | 213 | else |
214 | { | |
28e557ef | 215 | widest_int cval = wi::bit_and_not (wi::to_widest (val.value), |
216 | val.mask); | |
e913b5cd | 217 | fprintf (outf, "%sCONSTANT ", prefix); |
218 | print_hex (cval, outf); | |
219 | fprintf (outf, " ("); | |
220 | print_hex (val.mask, outf); | |
221 | fprintf (outf, ")"); | |
b7e55469 | 222 | } |
41511585 | 223 | break; |
224 | default: | |
8c0963c4 | 225 | gcc_unreachable (); |
41511585 | 226 | } |
01406fc0 | 227 | } |
4ee9c684 | 228 | |
4ee9c684 | 229 | |
88dbf20f | 230 | /* Print lattice value VAL to stderr. */ |
231 | ||
9908fe4d | 232 | void debug_lattice_value (ccp_prop_value_t val); |
88dbf20f | 233 | |
4b987fac | 234 | DEBUG_FUNCTION void |
9908fe4d | 235 | debug_lattice_value (ccp_prop_value_t val) |
88dbf20f | 236 | { |
237 | dump_lattice_value (stderr, "", val); | |
238 | fprintf (stderr, "\n"); | |
239 | } | |
4ee9c684 | 240 | |
9c1be15e | 241 | /* Extend NONZERO_BITS to a full mask, with the upper bits being set. */ |
242 | ||
243 | static widest_int | |
244 | extend_mask (const wide_int &nonzero_bits) | |
245 | { | |
246 | return (wi::mask <widest_int> (wi::get_precision (nonzero_bits), true) | |
247 | | widest_int::from (nonzero_bits, UNSIGNED)); | |
248 | } | |
4ee9c684 | 249 | |
88dbf20f | 250 | /* Compute a default value for variable VAR and store it in the |
251 | CONST_VAL array. The following rules are used to get default | |
252 | values: | |
01406fc0 | 253 | |
88dbf20f | 254 | 1- Global and static variables that are declared constant are |
255 | considered CONSTANT. | |
256 | ||
257 | 2- Any other value is considered UNDEFINED. This is useful when | |
41511585 | 258 | considering PHI nodes. PHI arguments that are undefined do not |
259 | change the constant value of the PHI node, which allows for more | |
88dbf20f | 260 | constants to be propagated. |
4ee9c684 | 261 | |
8883e700 | 262 | 3- Variables defined by statements other than assignments and PHI |
88dbf20f | 263 | nodes are considered VARYING. |
4ee9c684 | 264 | |
8883e700 | 265 | 4- Initial values of variables that are not GIMPLE registers are |
bfa30570 | 266 | considered VARYING. */ |
4ee9c684 | 267 | |
9908fe4d | 268 | static ccp_prop_value_t |
88dbf20f | 269 | get_default_value (tree var) |
270 | { | |
9908fe4d | 271 | ccp_prop_value_t val = { UNINITIALIZED, NULL_TREE, 0 }; |
8edeb88b | 272 | gimple stmt; |
273 | ||
274 | stmt = SSA_NAME_DEF_STMT (var); | |
275 | ||
276 | if (gimple_nop_p (stmt)) | |
4ee9c684 | 277 | { |
8edeb88b | 278 | /* Variables defined by an empty statement are those used |
279 | before being initialized. If VAR is a local variable, we | |
280 | can assume initially that it is UNDEFINED, otherwise we must | |
281 | consider it VARYING. */ | |
7c782c9b | 282 | if (!virtual_operand_p (var) |
283 | && TREE_CODE (SSA_NAME_VAR (var)) == VAR_DECL) | |
8edeb88b | 284 | val.lattice_val = UNDEFINED; |
285 | else | |
b7e55469 | 286 | { |
287 | val.lattice_val = VARYING; | |
e913b5cd | 288 | val.mask = -1; |
fc08b993 | 289 | if (flag_tree_bit_ccp) |
290 | { | |
9c1be15e | 291 | wide_int nonzero_bits = get_nonzero_bits (var); |
292 | if (nonzero_bits != -1) | |
fc08b993 | 293 | { |
294 | val.lattice_val = CONSTANT; | |
295 | val.value = build_zero_cst (TREE_TYPE (var)); | |
9c1be15e | 296 | val.mask = extend_mask (nonzero_bits); |
fc08b993 | 297 | } |
298 | } | |
b7e55469 | 299 | } |
4ee9c684 | 300 | } |
b45b214a | 301 | else if (is_gimple_assign (stmt)) |
41511585 | 302 | { |
8edeb88b | 303 | tree cst; |
304 | if (gimple_assign_single_p (stmt) | |
305 | && DECL_P (gimple_assign_rhs1 (stmt)) | |
306 | && (cst = get_symbol_constant_value (gimple_assign_rhs1 (stmt)))) | |
88dbf20f | 307 | { |
8edeb88b | 308 | val.lattice_val = CONSTANT; |
309 | val.value = cst; | |
88dbf20f | 310 | } |
311 | else | |
b45b214a | 312 | { |
313 | /* Any other variable defined by an assignment is considered | |
314 | UNDEFINED. */ | |
315 | val.lattice_val = UNDEFINED; | |
316 | } | |
317 | } | |
318 | else if ((is_gimple_call (stmt) | |
319 | && gimple_call_lhs (stmt) != NULL_TREE) | |
320 | || gimple_code (stmt) == GIMPLE_PHI) | |
321 | { | |
322 | /* A variable defined by a call or a PHI node is considered | |
323 | UNDEFINED. */ | |
324 | val.lattice_val = UNDEFINED; | |
8edeb88b | 325 | } |
326 | else | |
327 | { | |
328 | /* Otherwise, VAR will never take on a constant value. */ | |
329 | val.lattice_val = VARYING; | |
e913b5cd | 330 | val.mask = -1; |
41511585 | 331 | } |
4ee9c684 | 332 | |
41511585 | 333 | return val; |
334 | } | |
4ee9c684 | 335 | |
4ee9c684 | 336 | |
bfa30570 | 337 | /* Get the constant value associated with variable VAR. */ |
4ee9c684 | 338 | |
9908fe4d | 339 | static inline ccp_prop_value_t * |
bfa30570 | 340 | get_value (tree var) |
88dbf20f | 341 | { |
9908fe4d | 342 | ccp_prop_value_t *val; |
bfa30570 | 343 | |
285df01b | 344 | if (const_val == NULL |
345 | || SSA_NAME_VERSION (var) >= n_const_val) | |
e004838d | 346 | return NULL; |
347 | ||
348 | val = &const_val[SSA_NAME_VERSION (var)]; | |
bfa30570 | 349 | if (val->lattice_val == UNINITIALIZED) |
4ee9c684 | 350 | *val = get_default_value (var); |
351 | ||
f5faab84 | 352 | canonicalize_value (val); |
4af351a8 | 353 | |
4ee9c684 | 354 | return val; |
355 | } | |
356 | ||
15d138c9 | 357 | /* Return the constant tree value associated with VAR. */ |
358 | ||
359 | static inline tree | |
360 | get_constant_value (tree var) | |
361 | { | |
9908fe4d | 362 | ccp_prop_value_t *val; |
98d92e3c | 363 | if (TREE_CODE (var) != SSA_NAME) |
364 | { | |
365 | if (is_gimple_min_invariant (var)) | |
366 | return var; | |
367 | return NULL_TREE; | |
368 | } | |
369 | val = get_value (var); | |
b7e55469 | 370 | if (val |
371 | && val->lattice_val == CONSTANT | |
372 | && (TREE_CODE (val->value) != INTEGER_CST | |
796b6678 | 373 | || val->mask == 0)) |
15d138c9 | 374 | return val->value; |
375 | return NULL_TREE; | |
376 | } | |
377 | ||
bfa30570 | 378 | /* Sets the value associated with VAR to VARYING. */ |
379 | ||
380 | static inline void | |
381 | set_value_varying (tree var) | |
382 | { | |
9908fe4d | 383 | ccp_prop_value_t *val = &const_val[SSA_NAME_VERSION (var)]; |
bfa30570 | 384 | |
385 | val->lattice_val = VARYING; | |
386 | val->value = NULL_TREE; | |
e913b5cd | 387 | val->mask = -1; |
bfa30570 | 388 | } |
4ee9c684 | 389 | |
0001b944 | 390 | /* For integer constants, make sure to drop TREE_OVERFLOW. */ |
b31eb493 | 391 | |
392 | static void | |
9908fe4d | 393 | canonicalize_value (ccp_prop_value_t *val) |
b31eb493 | 394 | { |
f5faab84 | 395 | if (val->lattice_val != CONSTANT) |
396 | return; | |
397 | ||
398 | if (TREE_OVERFLOW_P (val->value)) | |
399 | val->value = drop_tree_overflow (val->value); | |
b31eb493 | 400 | } |
401 | ||
b7e55469 | 402 | /* Return whether the lattice transition is valid. */ |
403 | ||
404 | static bool | |
9908fe4d | 405 | valid_lattice_transition (ccp_prop_value_t old_val, ccp_prop_value_t new_val) |
b7e55469 | 406 | { |
407 | /* Lattice transitions must always be monotonically increasing in | |
408 | value. */ | |
409 | if (old_val.lattice_val < new_val.lattice_val) | |
410 | return true; | |
411 | ||
412 | if (old_val.lattice_val != new_val.lattice_val) | |
413 | return false; | |
414 | ||
415 | if (!old_val.value && !new_val.value) | |
416 | return true; | |
417 | ||
418 | /* Now both lattice values are CONSTANT. */ | |
419 | ||
fc6cc27b | 420 | /* Allow arbitrary copy changes as we might look through PHI <a_1, ...> |
421 | when only a single copy edge is executable. */ | |
422 | if (TREE_CODE (old_val.value) == SSA_NAME | |
423 | && TREE_CODE (new_val.value) == SSA_NAME) | |
424 | return true; | |
425 | ||
426 | /* Allow transitioning from a constant to a copy. */ | |
427 | if (is_gimple_min_invariant (old_val.value) | |
428 | && TREE_CODE (new_val.value) == SSA_NAME) | |
429 | return true; | |
430 | ||
43c92e0a | 431 | /* Allow transitioning from PHI <&x, not executable> == &x |
432 | to PHI <&x, &y> == common alignment. */ | |
b7e55469 | 433 | if (TREE_CODE (old_val.value) != INTEGER_CST |
434 | && TREE_CODE (new_val.value) == INTEGER_CST) | |
435 | return true; | |
436 | ||
437 | /* Bit-lattices have to agree in the still valid bits. */ | |
438 | if (TREE_CODE (old_val.value) == INTEGER_CST | |
439 | && TREE_CODE (new_val.value) == INTEGER_CST) | |
5de9d3ed | 440 | return (wi::bit_and_not (wi::to_widest (old_val.value), new_val.mask) |
441 | == wi::bit_and_not (wi::to_widest (new_val.value), new_val.mask)); | |
b7e55469 | 442 | |
443 | /* Otherwise constant values have to agree. */ | |
0001b944 | 444 | if (operand_equal_p (old_val.value, new_val.value, 0)) |
445 | return true; | |
446 | ||
447 | /* At least the kinds and types should agree now. */ | |
448 | if (TREE_CODE (old_val.value) != TREE_CODE (new_val.value) | |
449 | || !types_compatible_p (TREE_TYPE (old_val.value), | |
450 | TREE_TYPE (new_val.value))) | |
451 | return false; | |
452 | ||
453 | /* For floats and !HONOR_NANS allow transitions from (partial) NaN | |
454 | to non-NaN. */ | |
455 | tree type = TREE_TYPE (new_val.value); | |
456 | if (SCALAR_FLOAT_TYPE_P (type) | |
93633022 | 457 | && !HONOR_NANS (type)) |
0001b944 | 458 | { |
459 | if (REAL_VALUE_ISNAN (TREE_REAL_CST (old_val.value))) | |
460 | return true; | |
461 | } | |
462 | else if (VECTOR_FLOAT_TYPE_P (type) | |
93633022 | 463 | && !HONOR_NANS (type)) |
0001b944 | 464 | { |
465 | for (unsigned i = 0; i < VECTOR_CST_NELTS (old_val.value); ++i) | |
466 | if (!REAL_VALUE_ISNAN | |
467 | (TREE_REAL_CST (VECTOR_CST_ELT (old_val.value, i))) | |
468 | && !operand_equal_p (VECTOR_CST_ELT (old_val.value, i), | |
469 | VECTOR_CST_ELT (new_val.value, i), 0)) | |
470 | return false; | |
471 | return true; | |
472 | } | |
473 | else if (COMPLEX_FLOAT_TYPE_P (type) | |
93633022 | 474 | && !HONOR_NANS (type)) |
0001b944 | 475 | { |
476 | if (!REAL_VALUE_ISNAN (TREE_REAL_CST (TREE_REALPART (old_val.value))) | |
477 | && !operand_equal_p (TREE_REALPART (old_val.value), | |
478 | TREE_REALPART (new_val.value), 0)) | |
479 | return false; | |
480 | if (!REAL_VALUE_ISNAN (TREE_REAL_CST (TREE_IMAGPART (old_val.value))) | |
481 | && !operand_equal_p (TREE_IMAGPART (old_val.value), | |
482 | TREE_IMAGPART (new_val.value), 0)) | |
483 | return false; | |
484 | return true; | |
485 | } | |
486 | return false; | |
b7e55469 | 487 | } |
488 | ||
88dbf20f | 489 | /* Set the value for variable VAR to NEW_VAL. Return true if the new |
490 | value is different from VAR's previous value. */ | |
4ee9c684 | 491 | |
41511585 | 492 | static bool |
27de3d43 | 493 | set_lattice_value (tree var, ccp_prop_value_t *new_val) |
4ee9c684 | 494 | { |
6d0bf6d6 | 495 | /* We can deal with old UNINITIALIZED values just fine here. */ |
9908fe4d | 496 | ccp_prop_value_t *old_val = &const_val[SSA_NAME_VERSION (var)]; |
88dbf20f | 497 | |
27de3d43 | 498 | canonicalize_value (new_val); |
b31eb493 | 499 | |
b7e55469 | 500 | /* We have to be careful to not go up the bitwise lattice |
27de3d43 | 501 | represented by the mask. Instead of dropping to VARYING |
502 | use the meet operator to retain a conservative value. | |
503 | Missed optimizations like PR65851 makes this necessary. | |
504 | It also ensures we converge to a stable lattice solution. */ | |
505 | if (new_val->lattice_val == CONSTANT | |
b7e55469 | 506 | && old_val->lattice_val == CONSTANT |
27de3d43 | 507 | && TREE_CODE (new_val->value) != SSA_NAME) |
508 | ccp_lattice_meet (new_val, old_val); | |
bfa30570 | 509 | |
27de3d43 | 510 | gcc_checking_assert (valid_lattice_transition (*old_val, *new_val)); |
88dbf20f | 511 | |
b7e55469 | 512 | /* If *OLD_VAL and NEW_VAL are the same, return false to inform the |
513 | caller that this was a non-transition. */ | |
27de3d43 | 514 | if (old_val->lattice_val != new_val->lattice_val |
515 | || (new_val->lattice_val == CONSTANT | |
516 | && (TREE_CODE (new_val->value) != TREE_CODE (old_val->value) | |
517 | || (TREE_CODE (new_val->value) == INTEGER_CST | |
518 | && (new_val->mask != old_val->mask | |
bc1d3d97 | 519 | || (wi::bit_and_not (wi::to_widest (old_val->value), |
27de3d43 | 520 | new_val->mask) |
521 | != wi::bit_and_not (wi::to_widest (new_val->value), | |
522 | new_val->mask)))) | |
523 | || (TREE_CODE (new_val->value) != INTEGER_CST | |
524 | && !operand_equal_p (new_val->value, old_val->value, 0))))) | |
4ee9c684 | 525 | { |
b7e55469 | 526 | /* ??? We would like to delay creation of INTEGER_CSTs from |
527 | partially constants here. */ | |
528 | ||
41511585 | 529 | if (dump_file && (dump_flags & TDF_DETAILS)) |
530 | { | |
27de3d43 | 531 | dump_lattice_value (dump_file, "Lattice value changed to ", *new_val); |
bfa30570 | 532 | fprintf (dump_file, ". Adding SSA edges to worklist.\n"); |
41511585 | 533 | } |
534 | ||
27de3d43 | 535 | *old_val = *new_val; |
88dbf20f | 536 | |
27de3d43 | 537 | gcc_assert (new_val->lattice_val != UNINITIALIZED); |
bfa30570 | 538 | return true; |
4ee9c684 | 539 | } |
41511585 | 540 | |
541 | return false; | |
4ee9c684 | 542 | } |
543 | ||
9908fe4d | 544 | static ccp_prop_value_t get_value_for_expr (tree, bool); |
545 | static ccp_prop_value_t bit_value_binop (enum tree_code, tree, tree, tree); | |
5de9d3ed | 546 | static void bit_value_binop_1 (enum tree_code, tree, widest_int *, widest_int *, |
10c3fe8d | 547 | tree, const widest_int &, const widest_int &, |
548 | tree, const widest_int &, const widest_int &); | |
b7e55469 | 549 | |
5de9d3ed | 550 | /* Return a widest_int that can be used for bitwise simplifications |
b7e55469 | 551 | from VAL. */ |
552 | ||
5de9d3ed | 553 | static widest_int |
9908fe4d | 554 | value_to_wide_int (ccp_prop_value_t val) |
b7e55469 | 555 | { |
556 | if (val.value | |
557 | && TREE_CODE (val.value) == INTEGER_CST) | |
5de9d3ed | 558 | return wi::to_widest (val.value); |
e913b5cd | 559 | |
560 | return 0; | |
b7e55469 | 561 | } |
562 | ||
563 | /* Return the value for the address expression EXPR based on alignment | |
564 | information. */ | |
6d0bf6d6 | 565 | |
9908fe4d | 566 | static ccp_prop_value_t |
b7e55469 | 567 | get_value_from_alignment (tree expr) |
568 | { | |
f8abb542 | 569 | tree type = TREE_TYPE (expr); |
9908fe4d | 570 | ccp_prop_value_t val; |
f8abb542 | 571 | unsigned HOST_WIDE_INT bitpos; |
572 | unsigned int align; | |
b7e55469 | 573 | |
574 | gcc_assert (TREE_CODE (expr) == ADDR_EXPR); | |
575 | ||
59da1bcd | 576 | get_pointer_alignment_1 (expr, &align, &bitpos); |
cf8f0e63 | 577 | val.mask = (POINTER_TYPE_P (type) || TYPE_UNSIGNED (type) |
5de9d3ed | 578 | ? wi::mask <widest_int> (TYPE_PRECISION (type), false) |
e913b5cd | 579 | : -1).and_not (align / BITS_PER_UNIT - 1); |
c90d2c17 | 580 | val.lattice_val |
581 | = wi::sext (val.mask, TYPE_PRECISION (type)) == -1 ? VARYING : CONSTANT; | |
f8abb542 | 582 | if (val.lattice_val == CONSTANT) |
796b6678 | 583 | val.value = build_int_cstu (type, bitpos / BITS_PER_UNIT); |
b7e55469 | 584 | else |
f8abb542 | 585 | val.value = NULL_TREE; |
b7e55469 | 586 | |
587 | return val; | |
588 | } | |
589 | ||
590 | /* Return the value for the tree operand EXPR. If FOR_BITS_P is true | |
591 | return constant bits extracted from alignment information for | |
592 | invariant addresses. */ | |
593 | ||
9908fe4d | 594 | static ccp_prop_value_t |
b7e55469 | 595 | get_value_for_expr (tree expr, bool for_bits_p) |
6d0bf6d6 | 596 | { |
9908fe4d | 597 | ccp_prop_value_t val; |
6d0bf6d6 | 598 | |
599 | if (TREE_CODE (expr) == SSA_NAME) | |
b7e55469 | 600 | { |
601 | val = *get_value (expr); | |
602 | if (for_bits_p | |
603 | && val.lattice_val == CONSTANT | |
604 | && TREE_CODE (val.value) == ADDR_EXPR) | |
605 | val = get_value_from_alignment (val.value); | |
bc1d3d97 | 606 | /* Fall back to a copy value. */ |
607 | if (!for_bits_p | |
608 | && val.lattice_val == VARYING | |
609 | && !SSA_NAME_OCCURS_IN_ABNORMAL_PHI (expr)) | |
610 | { | |
611 | val.lattice_val = CONSTANT; | |
612 | val.value = expr; | |
613 | val.mask = -1; | |
614 | } | |
b7e55469 | 615 | } |
616 | else if (is_gimple_min_invariant (expr) | |
617 | && (!for_bits_p || TREE_CODE (expr) != ADDR_EXPR)) | |
6d0bf6d6 | 618 | { |
619 | val.lattice_val = CONSTANT; | |
620 | val.value = expr; | |
e913b5cd | 621 | val.mask = 0; |
f5faab84 | 622 | canonicalize_value (&val); |
6d0bf6d6 | 623 | } |
b7e55469 | 624 | else if (TREE_CODE (expr) == ADDR_EXPR) |
625 | val = get_value_from_alignment (expr); | |
6d0bf6d6 | 626 | else |
627 | { | |
628 | val.lattice_val = VARYING; | |
09b2913a | 629 | val.mask = -1; |
6d0bf6d6 | 630 | val.value = NULL_TREE; |
631 | } | |
6d0bf6d6 | 632 | return val; |
633 | } | |
634 | ||
88dbf20f | 635 | /* Return the likely CCP lattice value for STMT. |
4ee9c684 | 636 | |
41511585 | 637 | If STMT has no operands, then return CONSTANT. |
4ee9c684 | 638 | |
d61b9af3 | 639 | Else if undefinedness of operands of STMT cause its value to be |
640 | undefined, then return UNDEFINED. | |
4ee9c684 | 641 | |
41511585 | 642 | Else if any operands of STMT are constants, then return CONSTANT. |
4ee9c684 | 643 | |
41511585 | 644 | Else return VARYING. */ |
4ee9c684 | 645 | |
88dbf20f | 646 | static ccp_lattice_t |
75a70cf9 | 647 | likely_value (gimple stmt) |
41511585 | 648 | { |
d61b9af3 | 649 | bool has_constant_operand, has_undefined_operand, all_undefined_operands; |
a8a0d56e | 650 | bool has_nsa_operand; |
41511585 | 651 | tree use; |
652 | ssa_op_iter iter; | |
8edeb88b | 653 | unsigned i; |
4ee9c684 | 654 | |
590c3166 | 655 | enum gimple_code code = gimple_code (stmt); |
75a70cf9 | 656 | |
657 | /* This function appears to be called only for assignments, calls, | |
658 | conditionals, and switches, due to the logic in visit_stmt. */ | |
659 | gcc_assert (code == GIMPLE_ASSIGN | |
660 | || code == GIMPLE_CALL | |
661 | || code == GIMPLE_COND | |
662 | || code == GIMPLE_SWITCH); | |
88dbf20f | 663 | |
664 | /* If the statement has volatile operands, it won't fold to a | |
665 | constant value. */ | |
75a70cf9 | 666 | if (gimple_has_volatile_ops (stmt)) |
88dbf20f | 667 | return VARYING; |
668 | ||
75a70cf9 | 669 | /* Arrive here for more complex cases. */ |
bfa30570 | 670 | has_constant_operand = false; |
d61b9af3 | 671 | has_undefined_operand = false; |
672 | all_undefined_operands = true; | |
a8a0d56e | 673 | has_nsa_operand = false; |
8edeb88b | 674 | FOR_EACH_SSA_TREE_OPERAND (use, stmt, iter, SSA_OP_USE) |
41511585 | 675 | { |
9908fe4d | 676 | ccp_prop_value_t *val = get_value (use); |
41511585 | 677 | |
bfa30570 | 678 | if (val->lattice_val == UNDEFINED) |
d61b9af3 | 679 | has_undefined_operand = true; |
680 | else | |
681 | all_undefined_operands = false; | |
88dbf20f | 682 | |
41511585 | 683 | if (val->lattice_val == CONSTANT) |
bfa30570 | 684 | has_constant_operand = true; |
a8a0d56e | 685 | |
686 | if (SSA_NAME_IS_DEFAULT_DEF (use) | |
687 | || !prop_simulate_again_p (SSA_NAME_DEF_STMT (use))) | |
688 | has_nsa_operand = true; | |
4ee9c684 | 689 | } |
41511585 | 690 | |
dd277d48 | 691 | /* There may be constants in regular rhs operands. For calls we |
692 | have to ignore lhs, fndecl and static chain, otherwise only | |
693 | the lhs. */ | |
694 | for (i = (is_gimple_call (stmt) ? 2 : 0) + gimple_has_lhs (stmt); | |
8edeb88b | 695 | i < gimple_num_ops (stmt); ++i) |
696 | { | |
697 | tree op = gimple_op (stmt, i); | |
698 | if (!op || TREE_CODE (op) == SSA_NAME) | |
699 | continue; | |
700 | if (is_gimple_min_invariant (op)) | |
701 | has_constant_operand = true; | |
702 | } | |
703 | ||
87c0a9fc | 704 | if (has_constant_operand) |
705 | all_undefined_operands = false; | |
706 | ||
3d483a94 | 707 | if (has_undefined_operand |
708 | && code == GIMPLE_CALL | |
709 | && gimple_call_internal_p (stmt)) | |
710 | switch (gimple_call_internal_fn (stmt)) | |
711 | { | |
712 | /* These 3 builtins use the first argument just as a magic | |
713 | way how to find out a decl uid. */ | |
714 | case IFN_GOMP_SIMD_LANE: | |
715 | case IFN_GOMP_SIMD_VF: | |
716 | case IFN_GOMP_SIMD_LAST_LANE: | |
717 | has_undefined_operand = false; | |
718 | break; | |
719 | default: | |
720 | break; | |
721 | } | |
722 | ||
d61b9af3 | 723 | /* If the operation combines operands like COMPLEX_EXPR make sure to |
724 | not mark the result UNDEFINED if only one part of the result is | |
725 | undefined. */ | |
75a70cf9 | 726 | if (has_undefined_operand && all_undefined_operands) |
d61b9af3 | 727 | return UNDEFINED; |
75a70cf9 | 728 | else if (code == GIMPLE_ASSIGN && has_undefined_operand) |
d61b9af3 | 729 | { |
75a70cf9 | 730 | switch (gimple_assign_rhs_code (stmt)) |
d61b9af3 | 731 | { |
732 | /* Unary operators are handled with all_undefined_operands. */ | |
733 | case PLUS_EXPR: | |
734 | case MINUS_EXPR: | |
d61b9af3 | 735 | case POINTER_PLUS_EXPR: |
d61b9af3 | 736 | /* Not MIN_EXPR, MAX_EXPR. One VARYING operand may be selected. |
737 | Not bitwise operators, one VARYING operand may specify the | |
738 | result completely. Not logical operators for the same reason. | |
05a936a0 | 739 | Not COMPLEX_EXPR as one VARYING operand makes the result partly |
740 | not UNDEFINED. Not *DIV_EXPR, comparisons and shifts because | |
741 | the undefined operand may be promoted. */ | |
d61b9af3 | 742 | return UNDEFINED; |
743 | ||
43c92e0a | 744 | case ADDR_EXPR: |
745 | /* If any part of an address is UNDEFINED, like the index | |
746 | of an ARRAY_EXPR, then treat the result as UNDEFINED. */ | |
747 | return UNDEFINED; | |
748 | ||
d61b9af3 | 749 | default: |
750 | ; | |
751 | } | |
752 | } | |
753 | /* If there was an UNDEFINED operand but the result may be not UNDEFINED | |
c91fedc5 | 754 | fall back to CONSTANT. During iteration UNDEFINED may still drop |
755 | to CONSTANT. */ | |
d61b9af3 | 756 | if (has_undefined_operand) |
c91fedc5 | 757 | return CONSTANT; |
d61b9af3 | 758 | |
8edeb88b | 759 | /* We do not consider virtual operands here -- load from read-only |
760 | memory may have only VARYING virtual operands, but still be | |
a8a0d56e | 761 | constant. Also we can combine the stmt with definitions from |
762 | operands whose definitions are not simulated again. */ | |
bfa30570 | 763 | if (has_constant_operand |
a8a0d56e | 764 | || has_nsa_operand |
8edeb88b | 765 | || gimple_references_memory_p (stmt)) |
88dbf20f | 766 | return CONSTANT; |
767 | ||
bfa30570 | 768 | return VARYING; |
4ee9c684 | 769 | } |
770 | ||
bfa30570 | 771 | /* Returns true if STMT cannot be constant. */ |
772 | ||
773 | static bool | |
75a70cf9 | 774 | surely_varying_stmt_p (gimple stmt) |
bfa30570 | 775 | { |
776 | /* If the statement has operands that we cannot handle, it cannot be | |
777 | constant. */ | |
75a70cf9 | 778 | if (gimple_has_volatile_ops (stmt)) |
bfa30570 | 779 | return true; |
780 | ||
f257af64 | 781 | /* If it is a call and does not return a value or is not a |
237e78b1 | 782 | builtin and not an indirect call or a call to function with |
783 | assume_aligned/alloc_align attribute, it is varying. */ | |
75a70cf9 | 784 | if (is_gimple_call (stmt)) |
f257af64 | 785 | { |
237e78b1 | 786 | tree fndecl, fntype = gimple_call_fntype (stmt); |
f257af64 | 787 | if (!gimple_call_lhs (stmt) |
788 | || ((fndecl = gimple_call_fndecl (stmt)) != NULL_TREE | |
237e78b1 | 789 | && !DECL_BUILT_IN (fndecl) |
790 | && !lookup_attribute ("assume_aligned", | |
791 | TYPE_ATTRIBUTES (fntype)) | |
792 | && !lookup_attribute ("alloc_align", | |
793 | TYPE_ATTRIBUTES (fntype)))) | |
f257af64 | 794 | return true; |
795 | } | |
bfa30570 | 796 | |
8edeb88b | 797 | /* Any other store operation is not interesting. */ |
dd277d48 | 798 | else if (gimple_vdef (stmt)) |
8edeb88b | 799 | return true; |
800 | ||
bfa30570 | 801 | /* Anything other than assignments and conditional jumps are not |
802 | interesting for CCP. */ | |
75a70cf9 | 803 | if (gimple_code (stmt) != GIMPLE_ASSIGN |
f257af64 | 804 | && gimple_code (stmt) != GIMPLE_COND |
805 | && gimple_code (stmt) != GIMPLE_SWITCH | |
806 | && gimple_code (stmt) != GIMPLE_CALL) | |
bfa30570 | 807 | return true; |
808 | ||
809 | return false; | |
810 | } | |
4ee9c684 | 811 | |
41511585 | 812 | /* Initialize local data structures for CCP. */ |
4ee9c684 | 813 | |
814 | static void | |
41511585 | 815 | ccp_initialize (void) |
4ee9c684 | 816 | { |
41511585 | 817 | basic_block bb; |
4ee9c684 | 818 | |
285df01b | 819 | n_const_val = num_ssa_names; |
9908fe4d | 820 | const_val = XCNEWVEC (ccp_prop_value_t, n_const_val); |
4ee9c684 | 821 | |
41511585 | 822 | /* Initialize simulation flags for PHI nodes and statements. */ |
fc00614f | 823 | FOR_EACH_BB_FN (bb, cfun) |
4ee9c684 | 824 | { |
75a70cf9 | 825 | gimple_stmt_iterator i; |
4ee9c684 | 826 | |
75a70cf9 | 827 | for (i = gsi_start_bb (bb); !gsi_end_p (i); gsi_next (&i)) |
41511585 | 828 | { |
75a70cf9 | 829 | gimple stmt = gsi_stmt (i); |
2193544e | 830 | bool is_varying; |
831 | ||
832 | /* If the statement is a control insn, then we do not | |
833 | want to avoid simulating the statement once. Failure | |
834 | to do so means that those edges will never get added. */ | |
835 | if (stmt_ends_bb_p (stmt)) | |
836 | is_varying = false; | |
837 | else | |
838 | is_varying = surely_varying_stmt_p (stmt); | |
4ee9c684 | 839 | |
bfa30570 | 840 | if (is_varying) |
41511585 | 841 | { |
88dbf20f | 842 | tree def; |
843 | ssa_op_iter iter; | |
844 | ||
845 | /* If the statement will not produce a constant, mark | |
846 | all its outputs VARYING. */ | |
847 | FOR_EACH_SSA_TREE_OPERAND (def, stmt, iter, SSA_OP_ALL_DEFS) | |
8edeb88b | 848 | set_value_varying (def); |
41511585 | 849 | } |
75a70cf9 | 850 | prop_set_simulate_again (stmt, !is_varying); |
41511585 | 851 | } |
4ee9c684 | 852 | } |
853 | ||
75a70cf9 | 854 | /* Now process PHI nodes. We never clear the simulate_again flag on |
855 | phi nodes, since we do not know which edges are executable yet, | |
856 | except for phi nodes for virtual operands when we do not do store ccp. */ | |
fc00614f | 857 | FOR_EACH_BB_FN (bb, cfun) |
4ee9c684 | 858 | { |
1a91d914 | 859 | gphi_iterator i; |
41511585 | 860 | |
75a70cf9 | 861 | for (i = gsi_start_phis (bb); !gsi_end_p (i); gsi_next (&i)) |
862 | { | |
1a91d914 | 863 | gphi *phi = i.phi (); |
75a70cf9 | 864 | |
7c782c9b | 865 | if (virtual_operand_p (gimple_phi_result (phi))) |
75a70cf9 | 866 | prop_set_simulate_again (phi, false); |
bfa30570 | 867 | else |
75a70cf9 | 868 | prop_set_simulate_again (phi, true); |
41511585 | 869 | } |
4ee9c684 | 870 | } |
41511585 | 871 | } |
4ee9c684 | 872 | |
43fb76c1 | 873 | /* Debug count support. Reset the values of ssa names |
874 | VARYING when the total number ssa names analyzed is | |
875 | beyond the debug count specified. */ | |
876 | ||
877 | static void | |
878 | do_dbg_cnt (void) | |
879 | { | |
880 | unsigned i; | |
881 | for (i = 0; i < num_ssa_names; i++) | |
882 | { | |
883 | if (!dbg_cnt (ccp)) | |
884 | { | |
885 | const_val[i].lattice_val = VARYING; | |
e913b5cd | 886 | const_val[i].mask = -1; |
43fb76c1 | 887 | const_val[i].value = NULL_TREE; |
888 | } | |
889 | } | |
890 | } | |
891 | ||
4ee9c684 | 892 | |
88dbf20f | 893 | /* Do final substitution of propagated values, cleanup the flowgraph and |
48e1416a | 894 | free allocated storage. |
4ee9c684 | 895 | |
33a34f1e | 896 | Return TRUE when something was optimized. */ |
897 | ||
898 | static bool | |
88dbf20f | 899 | ccp_finalize (void) |
4ee9c684 | 900 | { |
43fb76c1 | 901 | bool something_changed; |
153c3b50 | 902 | unsigned i; |
43fb76c1 | 903 | |
904 | do_dbg_cnt (); | |
153c3b50 | 905 | |
906 | /* Derive alignment and misalignment information from partially | |
fc08b993 | 907 | constant pointers in the lattice or nonzero bits from partially |
908 | constant integers. */ | |
153c3b50 | 909 | for (i = 1; i < num_ssa_names; ++i) |
910 | { | |
911 | tree name = ssa_name (i); | |
9908fe4d | 912 | ccp_prop_value_t *val; |
153c3b50 | 913 | unsigned int tem, align; |
914 | ||
915 | if (!name | |
fc08b993 | 916 | || (!POINTER_TYPE_P (TREE_TYPE (name)) |
917 | && (!INTEGRAL_TYPE_P (TREE_TYPE (name)) | |
918 | /* Don't record nonzero bits before IPA to avoid | |
919 | using too much memory. */ | |
920 | || first_pass_instance))) | |
153c3b50 | 921 | continue; |
922 | ||
923 | val = get_value (name); | |
924 | if (val->lattice_val != CONSTANT | |
925 | || TREE_CODE (val->value) != INTEGER_CST) | |
926 | continue; | |
927 | ||
fc08b993 | 928 | if (POINTER_TYPE_P (TREE_TYPE (name))) |
929 | { | |
930 | /* Trailing mask bits specify the alignment, trailing value | |
931 | bits the misalignment. */ | |
aeb682a2 | 932 | tem = val->mask.to_uhwi (); |
fc08b993 | 933 | align = (tem & -tem); |
934 | if (align > 1) | |
935 | set_ptr_info_alignment (get_ptr_info (name), align, | |
f9ae6f95 | 936 | (TREE_INT_CST_LOW (val->value) |
fc08b993 | 937 | & (align - 1))); |
938 | } | |
939 | else | |
940 | { | |
9c1be15e | 941 | unsigned int precision = TYPE_PRECISION (TREE_TYPE (val->value)); |
942 | wide_int nonzero_bits = wide_int::from (val->mask, precision, | |
943 | UNSIGNED) | val->value; | |
fc08b993 | 944 | nonzero_bits &= get_nonzero_bits (name); |
945 | set_nonzero_bits (name, nonzero_bits); | |
946 | } | |
153c3b50 | 947 | } |
948 | ||
88dbf20f | 949 | /* Perform substitutions based on the known constant values. */ |
14f101cf | 950 | something_changed = substitute_and_fold (get_constant_value, |
951 | ccp_fold_stmt, true); | |
4ee9c684 | 952 | |
88dbf20f | 953 | free (const_val); |
e004838d | 954 | const_val = NULL; |
33a34f1e | 955 | return something_changed;; |
4ee9c684 | 956 | } |
957 | ||
958 | ||
88dbf20f | 959 | /* Compute the meet operator between *VAL1 and *VAL2. Store the result |
960 | in VAL1. | |
961 | ||
962 | any M UNDEFINED = any | |
88dbf20f | 963 | any M VARYING = VARYING |
964 | Ci M Cj = Ci if (i == j) | |
965 | Ci M Cj = VARYING if (i != j) | |
bfa30570 | 966 | */ |
4ee9c684 | 967 | |
968 | static void | |
27de3d43 | 969 | ccp_lattice_meet (ccp_prop_value_t *val1, ccp_prop_value_t *val2) |
4ee9c684 | 970 | { |
fc6cc27b | 971 | if (val1->lattice_val == UNDEFINED |
972 | /* For UNDEFINED M SSA we can't always SSA because its definition | |
973 | may not dominate the PHI node. Doing optimistic copy propagation | |
974 | also causes a lot of gcc.dg/uninit-pred*.c FAILs. */ | |
975 | && (val2->lattice_val != CONSTANT | |
976 | || TREE_CODE (val2->value) != SSA_NAME)) | |
4ee9c684 | 977 | { |
88dbf20f | 978 | /* UNDEFINED M any = any */ |
979 | *val1 = *val2; | |
41511585 | 980 | } |
fc6cc27b | 981 | else if (val2->lattice_val == UNDEFINED |
982 | /* See above. */ | |
983 | && (val1->lattice_val != CONSTANT | |
984 | || TREE_CODE (val1->value) != SSA_NAME)) | |
92481a4d | 985 | { |
88dbf20f | 986 | /* any M UNDEFINED = any |
987 | Nothing to do. VAL1 already contains the value we want. */ | |
988 | ; | |
92481a4d | 989 | } |
88dbf20f | 990 | else if (val1->lattice_val == VARYING |
991 | || val2->lattice_val == VARYING) | |
41511585 | 992 | { |
88dbf20f | 993 | /* any M VARYING = VARYING. */ |
994 | val1->lattice_val = VARYING; | |
e913b5cd | 995 | val1->mask = -1; |
88dbf20f | 996 | val1->value = NULL_TREE; |
41511585 | 997 | } |
b7e55469 | 998 | else if (val1->lattice_val == CONSTANT |
999 | && val2->lattice_val == CONSTANT | |
1000 | && TREE_CODE (val1->value) == INTEGER_CST | |
1001 | && TREE_CODE (val2->value) == INTEGER_CST) | |
1002 | { | |
1003 | /* Ci M Cj = Ci if (i == j) | |
1004 | Ci M Cj = VARYING if (i != j) | |
1005 | ||
1006 | For INTEGER_CSTs mask unequal bits. If no equal bits remain, | |
1007 | drop to varying. */ | |
e913b5cd | 1008 | val1->mask = (val1->mask | val2->mask |
5de9d3ed | 1009 | | (wi::to_widest (val1->value) |
1010 | ^ wi::to_widest (val2->value))); | |
c90d2c17 | 1011 | if (wi::sext (val1->mask, TYPE_PRECISION (TREE_TYPE (val1->value))) == -1) |
b7e55469 | 1012 | { |
1013 | val1->lattice_val = VARYING; | |
1014 | val1->value = NULL_TREE; | |
1015 | } | |
1016 | } | |
88dbf20f | 1017 | else if (val1->lattice_val == CONSTANT |
1018 | && val2->lattice_val == CONSTANT | |
27de3d43 | 1019 | && operand_equal_p (val1->value, val2->value, 0)) |
41511585 | 1020 | { |
88dbf20f | 1021 | /* Ci M Cj = Ci if (i == j) |
1022 | Ci M Cj = VARYING if (i != j) | |
1023 | ||
b7e55469 | 1024 | VAL1 already contains the value we want for equivalent values. */ |
1025 | } | |
1026 | else if (val1->lattice_val == CONSTANT | |
1027 | && val2->lattice_val == CONSTANT | |
1028 | && (TREE_CODE (val1->value) == ADDR_EXPR | |
1029 | || TREE_CODE (val2->value) == ADDR_EXPR)) | |
1030 | { | |
1031 | /* When not equal addresses are involved try meeting for | |
1032 | alignment. */ | |
9908fe4d | 1033 | ccp_prop_value_t tem = *val2; |
b7e55469 | 1034 | if (TREE_CODE (val1->value) == ADDR_EXPR) |
1035 | *val1 = get_value_for_expr (val1->value, true); | |
1036 | if (TREE_CODE (val2->value) == ADDR_EXPR) | |
1037 | tem = get_value_for_expr (val2->value, true); | |
27de3d43 | 1038 | ccp_lattice_meet (val1, &tem); |
41511585 | 1039 | } |
1040 | else | |
1041 | { | |
88dbf20f | 1042 | /* Any other combination is VARYING. */ |
1043 | val1->lattice_val = VARYING; | |
e913b5cd | 1044 | val1->mask = -1; |
88dbf20f | 1045 | val1->value = NULL_TREE; |
41511585 | 1046 | } |
4ee9c684 | 1047 | } |
1048 | ||
1049 | ||
41511585 | 1050 | /* Loop through the PHI_NODE's parameters for BLOCK and compare their |
1051 | lattice values to determine PHI_NODE's lattice value. The value of a | |
88dbf20f | 1052 | PHI node is determined calling ccp_lattice_meet with all the arguments |
41511585 | 1053 | of the PHI node that are incoming via executable edges. */ |
4ee9c684 | 1054 | |
41511585 | 1055 | static enum ssa_prop_result |
1a91d914 | 1056 | ccp_visit_phi_node (gphi *phi) |
4ee9c684 | 1057 | { |
75a70cf9 | 1058 | unsigned i; |
bc1d3d97 | 1059 | ccp_prop_value_t new_val; |
4ee9c684 | 1060 | |
41511585 | 1061 | if (dump_file && (dump_flags & TDF_DETAILS)) |
4ee9c684 | 1062 | { |
41511585 | 1063 | fprintf (dump_file, "\nVisiting PHI node: "); |
75a70cf9 | 1064 | print_gimple_stmt (dump_file, phi, 0, dump_flags); |
4ee9c684 | 1065 | } |
4ee9c684 | 1066 | |
bc1d3d97 | 1067 | new_val.lattice_val = UNDEFINED; |
1068 | new_val.value = NULL_TREE; | |
1069 | new_val.mask = 0; | |
4ee9c684 | 1070 | |
bc1d3d97 | 1071 | bool first = true; |
83c60000 | 1072 | bool non_exec_edge = false; |
75a70cf9 | 1073 | for (i = 0; i < gimple_phi_num_args (phi); i++) |
41511585 | 1074 | { |
88dbf20f | 1075 | /* Compute the meet operator over all the PHI arguments flowing |
1076 | through executable edges. */ | |
75a70cf9 | 1077 | edge e = gimple_phi_arg_edge (phi, i); |
4ee9c684 | 1078 | |
41511585 | 1079 | if (dump_file && (dump_flags & TDF_DETAILS)) |
1080 | { | |
1081 | fprintf (dump_file, | |
1082 | "\n Argument #%d (%d -> %d %sexecutable)\n", | |
1083 | i, e->src->index, e->dest->index, | |
1084 | (e->flags & EDGE_EXECUTABLE) ? "" : "not "); | |
1085 | } | |
1086 | ||
1087 | /* If the incoming edge is executable, Compute the meet operator for | |
1088 | the existing value of the PHI node and the current PHI argument. */ | |
1089 | if (e->flags & EDGE_EXECUTABLE) | |
1090 | { | |
75a70cf9 | 1091 | tree arg = gimple_phi_arg (phi, i)->def; |
9908fe4d | 1092 | ccp_prop_value_t arg_val = get_value_for_expr (arg, false); |
4ee9c684 | 1093 | |
bc1d3d97 | 1094 | if (first) |
1095 | { | |
1096 | new_val = arg_val; | |
1097 | first = false; | |
1098 | } | |
1099 | else | |
27de3d43 | 1100 | ccp_lattice_meet (&new_val, &arg_val); |
4ee9c684 | 1101 | |
41511585 | 1102 | if (dump_file && (dump_flags & TDF_DETAILS)) |
1103 | { | |
1104 | fprintf (dump_file, "\t"); | |
88dbf20f | 1105 | print_generic_expr (dump_file, arg, dump_flags); |
1106 | dump_lattice_value (dump_file, "\tValue: ", arg_val); | |
41511585 | 1107 | fprintf (dump_file, "\n"); |
1108 | } | |
4ee9c684 | 1109 | |
41511585 | 1110 | if (new_val.lattice_val == VARYING) |
1111 | break; | |
1112 | } | |
83c60000 | 1113 | else |
1114 | non_exec_edge = true; | |
1115 | } | |
1116 | ||
1117 | /* In case there were non-executable edges and the value is a copy | |
1118 | make sure its definition dominates the PHI node. */ | |
1119 | if (non_exec_edge | |
1120 | && new_val.lattice_val == CONSTANT | |
1121 | && TREE_CODE (new_val.value) == SSA_NAME | |
1122 | && ! SSA_NAME_IS_DEFAULT_DEF (new_val.value) | |
1123 | && ! dominated_by_p (CDI_DOMINATORS, gimple_bb (phi), | |
1124 | gimple_bb (SSA_NAME_DEF_STMT (new_val.value)))) | |
1125 | { | |
1126 | new_val.lattice_val = VARYING; | |
1127 | new_val.value = NULL_TREE; | |
1128 | new_val.mask = -1; | |
41511585 | 1129 | } |
4ee9c684 | 1130 | |
1131 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
41511585 | 1132 | { |
1133 | dump_lattice_value (dump_file, "\n PHI node value: ", new_val); | |
1134 | fprintf (dump_file, "\n\n"); | |
1135 | } | |
1136 | ||
bfa30570 | 1137 | /* Make the transition to the new value. */ |
27de3d43 | 1138 | if (set_lattice_value (gimple_phi_result (phi), &new_val)) |
41511585 | 1139 | { |
1140 | if (new_val.lattice_val == VARYING) | |
1141 | return SSA_PROP_VARYING; | |
1142 | else | |
1143 | return SSA_PROP_INTERESTING; | |
1144 | } | |
1145 | else | |
1146 | return SSA_PROP_NOT_INTERESTING; | |
4ee9c684 | 1147 | } |
1148 | ||
15d138c9 | 1149 | /* Return the constant value for OP or OP otherwise. */ |
00f4f705 | 1150 | |
1151 | static tree | |
15d138c9 | 1152 | valueize_op (tree op) |
00f4f705 | 1153 | { |
00f4f705 | 1154 | if (TREE_CODE (op) == SSA_NAME) |
1155 | { | |
15d138c9 | 1156 | tree tem = get_constant_value (op); |
1157 | if (tem) | |
1158 | return tem; | |
00f4f705 | 1159 | } |
1160 | return op; | |
1161 | } | |
1162 | ||
4e1b3545 | 1163 | /* Return the constant value for OP, but signal to not follow SSA |
1164 | edges if the definition may be simulated again. */ | |
1165 | ||
1166 | static tree | |
1167 | valueize_op_1 (tree op) | |
1168 | { | |
1169 | if (TREE_CODE (op) == SSA_NAME) | |
1170 | { | |
4e1b3545 | 1171 | /* If the definition may be simulated again we cannot follow |
1172 | this SSA edge as the SSA propagator does not necessarily | |
1173 | re-visit the use. */ | |
1174 | gimple def_stmt = SSA_NAME_DEF_STMT (op); | |
2160d5ba | 1175 | if (!gimple_nop_p (def_stmt) |
1176 | && prop_simulate_again_p (def_stmt)) | |
4e1b3545 | 1177 | return NULL_TREE; |
bc8fa068 | 1178 | tree tem = get_constant_value (op); |
1179 | if (tem) | |
1180 | return tem; | |
4e1b3545 | 1181 | } |
1182 | return op; | |
1183 | } | |
1184 | ||
41511585 | 1185 | /* CCP specific front-end to the non-destructive constant folding |
1186 | routines. | |
4ee9c684 | 1187 | |
1188 | Attempt to simplify the RHS of STMT knowing that one or more | |
1189 | operands are constants. | |
1190 | ||
1191 | If simplification is possible, return the simplified RHS, | |
75a70cf9 | 1192 | otherwise return the original RHS or NULL_TREE. */ |
4ee9c684 | 1193 | |
1194 | static tree | |
75a70cf9 | 1195 | ccp_fold (gimple stmt) |
4ee9c684 | 1196 | { |
389dd41b | 1197 | location_t loc = gimple_location (stmt); |
75a70cf9 | 1198 | switch (gimple_code (stmt)) |
88dbf20f | 1199 | { |
75a70cf9 | 1200 | case GIMPLE_COND: |
1201 | { | |
1202 | /* Handle comparison operators that can appear in GIMPLE form. */ | |
15d138c9 | 1203 | tree op0 = valueize_op (gimple_cond_lhs (stmt)); |
1204 | tree op1 = valueize_op (gimple_cond_rhs (stmt)); | |
75a70cf9 | 1205 | enum tree_code code = gimple_cond_code (stmt); |
389dd41b | 1206 | return fold_binary_loc (loc, code, boolean_type_node, op0, op1); |
75a70cf9 | 1207 | } |
4ee9c684 | 1208 | |
75a70cf9 | 1209 | case GIMPLE_SWITCH: |
1210 | { | |
15d138c9 | 1211 | /* Return the constant switch index. */ |
1a91d914 | 1212 | return valueize_op (gimple_switch_index (as_a <gswitch *> (stmt))); |
75a70cf9 | 1213 | } |
912f109f | 1214 | |
1d0b727d | 1215 | case GIMPLE_ASSIGN: |
1216 | case GIMPLE_CALL: | |
4e1b3545 | 1217 | return gimple_fold_stmt_to_constant_1 (stmt, |
1218 | valueize_op, valueize_op_1); | |
04236c3a | 1219 | |
8782adcf | 1220 | default: |
1d0b727d | 1221 | gcc_unreachable (); |
8782adcf | 1222 | } |
8782adcf | 1223 | } |
75a70cf9 | 1224 | |
b7e55469 | 1225 | /* Apply the operation CODE in type TYPE to the value, mask pair |
1226 | RVAL and RMASK representing a value of type RTYPE and set | |
1227 | the value, mask pair *VAL and *MASK to the result. */ | |
1228 | ||
1229 | static void | |
1230 | bit_value_unop_1 (enum tree_code code, tree type, | |
5de9d3ed | 1231 | widest_int *val, widest_int *mask, |
1232 | tree rtype, const widest_int &rval, const widest_int &rmask) | |
b7e55469 | 1233 | { |
1234 | switch (code) | |
1235 | { | |
1236 | case BIT_NOT_EXPR: | |
1237 | *mask = rmask; | |
cf8f0e63 | 1238 | *val = ~rval; |
b7e55469 | 1239 | break; |
1240 | ||
1241 | case NEGATE_EXPR: | |
1242 | { | |
5de9d3ed | 1243 | widest_int temv, temm; |
b7e55469 | 1244 | /* Return ~rval + 1. */ |
1245 | bit_value_unop_1 (BIT_NOT_EXPR, type, &temv, &temm, type, rval, rmask); | |
1246 | bit_value_binop_1 (PLUS_EXPR, type, val, mask, | |
e913b5cd | 1247 | type, temv, temm, type, 1, 0); |
b7e55469 | 1248 | break; |
1249 | } | |
1250 | ||
1251 | CASE_CONVERT: | |
1252 | { | |
e913b5cd | 1253 | signop sgn; |
b7e55469 | 1254 | |
1255 | /* First extend mask and value according to the original type. */ | |
e913b5cd | 1256 | sgn = TYPE_SIGN (rtype); |
796b6678 | 1257 | *mask = wi::ext (rmask, TYPE_PRECISION (rtype), sgn); |
1258 | *val = wi::ext (rval, TYPE_PRECISION (rtype), sgn); | |
b7e55469 | 1259 | |
1260 | /* Then extend mask and value according to the target type. */ | |
e913b5cd | 1261 | sgn = TYPE_SIGN (type); |
796b6678 | 1262 | *mask = wi::ext (*mask, TYPE_PRECISION (type), sgn); |
1263 | *val = wi::ext (*val, TYPE_PRECISION (type), sgn); | |
b7e55469 | 1264 | break; |
1265 | } | |
1266 | ||
1267 | default: | |
e913b5cd | 1268 | *mask = -1; |
b7e55469 | 1269 | break; |
1270 | } | |
1271 | } | |
1272 | ||
1273 | /* Apply the operation CODE in type TYPE to the value, mask pairs | |
1274 | R1VAL, R1MASK and R2VAL, R2MASK representing a values of type R1TYPE | |
1275 | and R2TYPE and set the value, mask pair *VAL and *MASK to the result. */ | |
1276 | ||
1277 | static void | |
1278 | bit_value_binop_1 (enum tree_code code, tree type, | |
5de9d3ed | 1279 | widest_int *val, widest_int *mask, |
10c3fe8d | 1280 | tree r1type, const widest_int &r1val, |
1281 | const widest_int &r1mask, tree r2type, | |
1282 | const widest_int &r2val, const widest_int &r2mask) | |
b7e55469 | 1283 | { |
e913b5cd | 1284 | signop sgn = TYPE_SIGN (type); |
1285 | int width = TYPE_PRECISION (type); | |
10c3fe8d | 1286 | bool swap_p = false; |
e913b5cd | 1287 | |
1288 | /* Assume we'll get a constant result. Use an initial non varying | |
1289 | value, we fall back to varying in the end if necessary. */ | |
1290 | *mask = -1; | |
1291 | ||
b7e55469 | 1292 | switch (code) |
1293 | { | |
1294 | case BIT_AND_EXPR: | |
1295 | /* The mask is constant where there is a known not | |
1296 | set bit, (m1 | m2) & ((v1 | m1) & (v2 | m2)) */ | |
cf8f0e63 | 1297 | *mask = (r1mask | r2mask) & (r1val | r1mask) & (r2val | r2mask); |
1298 | *val = r1val & r2val; | |
b7e55469 | 1299 | break; |
1300 | ||
1301 | case BIT_IOR_EXPR: | |
1302 | /* The mask is constant where there is a known | |
1303 | set bit, (m1 | m2) & ~((v1 & ~m1) | (v2 & ~m2)). */ | |
cf8f0e63 | 1304 | *mask = (r1mask | r2mask) |
1305 | .and_not (r1val.and_not (r1mask) | r2val.and_not (r2mask)); | |
1306 | *val = r1val | r2val; | |
b7e55469 | 1307 | break; |
1308 | ||
1309 | case BIT_XOR_EXPR: | |
1310 | /* m1 | m2 */ | |
cf8f0e63 | 1311 | *mask = r1mask | r2mask; |
1312 | *val = r1val ^ r2val; | |
b7e55469 | 1313 | break; |
1314 | ||
1315 | case LROTATE_EXPR: | |
1316 | case RROTATE_EXPR: | |
796b6678 | 1317 | if (r2mask == 0) |
b7e55469 | 1318 | { |
28e557ef | 1319 | widest_int shift = r2val; |
796b6678 | 1320 | if (shift == 0) |
e913b5cd | 1321 | { |
1322 | *mask = r1mask; | |
1323 | *val = r1val; | |
1324 | } | |
ddb1be65 | 1325 | else |
e913b5cd | 1326 | { |
796b6678 | 1327 | if (wi::neg_p (shift)) |
e913b5cd | 1328 | { |
1329 | shift = -shift; | |
1330 | if (code == RROTATE_EXPR) | |
1331 | code = LROTATE_EXPR; | |
1332 | else | |
1333 | code = RROTATE_EXPR; | |
1334 | } | |
1335 | if (code == RROTATE_EXPR) | |
1336 | { | |
796b6678 | 1337 | *mask = wi::rrotate (r1mask, shift, width); |
1338 | *val = wi::rrotate (r1val, shift, width); | |
e913b5cd | 1339 | } |
1340 | else | |
1341 | { | |
796b6678 | 1342 | *mask = wi::lrotate (r1mask, shift, width); |
1343 | *val = wi::lrotate (r1val, shift, width); | |
e913b5cd | 1344 | } |
1345 | } | |
b7e55469 | 1346 | } |
1347 | break; | |
1348 | ||
1349 | case LSHIFT_EXPR: | |
1350 | case RSHIFT_EXPR: | |
1351 | /* ??? We can handle partially known shift counts if we know | |
1352 | its sign. That way we can tell that (x << (y | 8)) & 255 | |
1353 | is zero. */ | |
796b6678 | 1354 | if (r2mask == 0) |
b7e55469 | 1355 | { |
28e557ef | 1356 | widest_int shift = r2val; |
796b6678 | 1357 | if (shift == 0) |
b7e55469 | 1358 | { |
1359 | *mask = r1mask; | |
1360 | *val = r1val; | |
1361 | } | |
ddb1be65 | 1362 | else |
e913b5cd | 1363 | { |
796b6678 | 1364 | if (wi::neg_p (shift)) |
e913b5cd | 1365 | { |
1366 | shift = -shift; | |
1367 | if (code == RSHIFT_EXPR) | |
1368 | code = LSHIFT_EXPR; | |
1369 | else | |
1370 | code = RSHIFT_EXPR; | |
1371 | } | |
1372 | if (code == RSHIFT_EXPR) | |
1373 | { | |
45639915 | 1374 | *mask = wi::rshift (wi::ext (r1mask, width, sgn), shift, sgn); |
1375 | *val = wi::rshift (wi::ext (r1val, width, sgn), shift, sgn); | |
e913b5cd | 1376 | } |
1377 | else | |
1378 | { | |
45639915 | 1379 | *mask = wi::ext (wi::lshift (r1mask, shift), width, sgn); |
1380 | *val = wi::ext (wi::lshift (r1val, shift), width, sgn); | |
e913b5cd | 1381 | } |
1382 | } | |
b7e55469 | 1383 | } |
1384 | break; | |
1385 | ||
1386 | case PLUS_EXPR: | |
1387 | case POINTER_PLUS_EXPR: | |
1388 | { | |
b7e55469 | 1389 | /* Do the addition with unknown bits set to zero, to give carry-ins of |
1390 | zero wherever possible. */ | |
ab2c1de8 | 1391 | widest_int lo = r1val.and_not (r1mask) + r2val.and_not (r2mask); |
796b6678 | 1392 | lo = wi::ext (lo, width, sgn); |
b7e55469 | 1393 | /* Do the addition with unknown bits set to one, to give carry-ins of |
1394 | one wherever possible. */ | |
ab2c1de8 | 1395 | widest_int hi = (r1val | r1mask) + (r2val | r2mask); |
796b6678 | 1396 | hi = wi::ext (hi, width, sgn); |
b7e55469 | 1397 | /* Each bit in the result is known if (a) the corresponding bits in |
1398 | both inputs are known, and (b) the carry-in to that bit position | |
1399 | is known. We can check condition (b) by seeing if we got the same | |
1400 | result with minimised carries as with maximised carries. */ | |
cf8f0e63 | 1401 | *mask = r1mask | r2mask | (lo ^ hi); |
796b6678 | 1402 | *mask = wi::ext (*mask, width, sgn); |
b7e55469 | 1403 | /* It shouldn't matter whether we choose lo or hi here. */ |
1404 | *val = lo; | |
1405 | break; | |
1406 | } | |
1407 | ||
1408 | case MINUS_EXPR: | |
1409 | { | |
5de9d3ed | 1410 | widest_int temv, temm; |
b7e55469 | 1411 | bit_value_unop_1 (NEGATE_EXPR, r2type, &temv, &temm, |
1412 | r2type, r2val, r2mask); | |
1413 | bit_value_binop_1 (PLUS_EXPR, type, val, mask, | |
1414 | r1type, r1val, r1mask, | |
1415 | r2type, temv, temm); | |
1416 | break; | |
1417 | } | |
1418 | ||
1419 | case MULT_EXPR: | |
1420 | { | |
1421 | /* Just track trailing zeros in both operands and transfer | |
1422 | them to the other. */ | |
796b6678 | 1423 | int r1tz = wi::ctz (r1val | r1mask); |
1424 | int r2tz = wi::ctz (r2val | r2mask); | |
e913b5cd | 1425 | if (r1tz + r2tz >= width) |
b7e55469 | 1426 | { |
e913b5cd | 1427 | *mask = 0; |
1428 | *val = 0; | |
b7e55469 | 1429 | } |
1430 | else if (r1tz + r2tz > 0) | |
1431 | { | |
5de9d3ed | 1432 | *mask = wi::ext (wi::mask <widest_int> (r1tz + r2tz, true), |
796b6678 | 1433 | width, sgn); |
e913b5cd | 1434 | *val = 0; |
b7e55469 | 1435 | } |
1436 | break; | |
1437 | } | |
1438 | ||
1439 | case EQ_EXPR: | |
1440 | case NE_EXPR: | |
1441 | { | |
5de9d3ed | 1442 | widest_int m = r1mask | r2mask; |
cf8f0e63 | 1443 | if (r1val.and_not (m) != r2val.and_not (m)) |
b7e55469 | 1444 | { |
e913b5cd | 1445 | *mask = 0; |
1446 | *val = ((code == EQ_EXPR) ? 0 : 1); | |
b7e55469 | 1447 | } |
1448 | else | |
1449 | { | |
1450 | /* We know the result of a comparison is always one or zero. */ | |
e913b5cd | 1451 | *mask = 1; |
1452 | *val = 0; | |
b7e55469 | 1453 | } |
1454 | break; | |
1455 | } | |
1456 | ||
1457 | case GE_EXPR: | |
1458 | case GT_EXPR: | |
10c3fe8d | 1459 | swap_p = true; |
1460 | code = swap_tree_comparison (code); | |
1461 | /* Fall through. */ | |
b7e55469 | 1462 | case LT_EXPR: |
1463 | case LE_EXPR: | |
1464 | { | |
1465 | int minmax, maxmin; | |
e913b5cd | 1466 | |
10c3fe8d | 1467 | const widest_int &o1val = swap_p ? r2val : r1val; |
1468 | const widest_int &o1mask = swap_p ? r2mask : r1mask; | |
1469 | const widest_int &o2val = swap_p ? r1val : r2val; | |
1470 | const widest_int &o2mask = swap_p ? r1mask : r2mask; | |
1471 | ||
b7e55469 | 1472 | /* If the most significant bits are not known we know nothing. */ |
796b6678 | 1473 | if (wi::neg_p (o1mask) || wi::neg_p (o2mask)) |
b7e55469 | 1474 | break; |
1475 | ||
90c0f5b7 | 1476 | /* For comparisons the signedness is in the comparison operands. */ |
e913b5cd | 1477 | sgn = TYPE_SIGN (r1type); |
90c0f5b7 | 1478 | |
b7e55469 | 1479 | /* If we know the most significant bits we know the values |
1480 | value ranges by means of treating varying bits as zero | |
1481 | or one. Do a cross comparison of the max/min pairs. */ | |
796b6678 | 1482 | maxmin = wi::cmp (o1val | o1mask, o2val.and_not (o2mask), sgn); |
1483 | minmax = wi::cmp (o1val.and_not (o1mask), o2val | o2mask, sgn); | |
e913b5cd | 1484 | if (maxmin < 0) /* o1 is less than o2. */ |
b7e55469 | 1485 | { |
e913b5cd | 1486 | *mask = 0; |
1487 | *val = 1; | |
b7e55469 | 1488 | } |
e913b5cd | 1489 | else if (minmax > 0) /* o1 is not less or equal to o2. */ |
b7e55469 | 1490 | { |
e913b5cd | 1491 | *mask = 0; |
1492 | *val = 0; | |
b7e55469 | 1493 | } |
e913b5cd | 1494 | else if (maxmin == minmax) /* o1 and o2 are equal. */ |
b7e55469 | 1495 | { |
1496 | /* This probably should never happen as we'd have | |
1497 | folded the thing during fully constant value folding. */ | |
e913b5cd | 1498 | *mask = 0; |
1499 | *val = (code == LE_EXPR ? 1 : 0); | |
b7e55469 | 1500 | } |
1501 | else | |
1502 | { | |
1503 | /* We know the result of a comparison is always one or zero. */ | |
e913b5cd | 1504 | *mask = 1; |
1505 | *val = 0; | |
b7e55469 | 1506 | } |
1507 | break; | |
1508 | } | |
1509 | ||
1510 | default:; | |
1511 | } | |
1512 | } | |
1513 | ||
1514 | /* Return the propagation value when applying the operation CODE to | |
1515 | the value RHS yielding type TYPE. */ | |
1516 | ||
9908fe4d | 1517 | static ccp_prop_value_t |
b7e55469 | 1518 | bit_value_unop (enum tree_code code, tree type, tree rhs) |
1519 | { | |
9908fe4d | 1520 | ccp_prop_value_t rval = get_value_for_expr (rhs, true); |
5de9d3ed | 1521 | widest_int value, mask; |
9908fe4d | 1522 | ccp_prop_value_t val; |
c91fedc5 | 1523 | |
1524 | if (rval.lattice_val == UNDEFINED) | |
1525 | return rval; | |
1526 | ||
b7e55469 | 1527 | gcc_assert ((rval.lattice_val == CONSTANT |
1528 | && TREE_CODE (rval.value) == INTEGER_CST) | |
c90d2c17 | 1529 | || wi::sext (rval.mask, TYPE_PRECISION (TREE_TYPE (rhs))) == -1); |
b7e55469 | 1530 | bit_value_unop_1 (code, type, &value, &mask, |
e913b5cd | 1531 | TREE_TYPE (rhs), value_to_wide_int (rval), rval.mask); |
c90d2c17 | 1532 | if (wi::sext (mask, TYPE_PRECISION (type)) != -1) |
b7e55469 | 1533 | { |
1534 | val.lattice_val = CONSTANT; | |
1535 | val.mask = mask; | |
1536 | /* ??? Delay building trees here. */ | |
e913b5cd | 1537 | val.value = wide_int_to_tree (type, value); |
b7e55469 | 1538 | } |
1539 | else | |
1540 | { | |
1541 | val.lattice_val = VARYING; | |
1542 | val.value = NULL_TREE; | |
e913b5cd | 1543 | val.mask = -1; |
b7e55469 | 1544 | } |
1545 | return val; | |
1546 | } | |
1547 | ||
1548 | /* Return the propagation value when applying the operation CODE to | |
1549 | the values RHS1 and RHS2 yielding type TYPE. */ | |
1550 | ||
9908fe4d | 1551 | static ccp_prop_value_t |
b7e55469 | 1552 | bit_value_binop (enum tree_code code, tree type, tree rhs1, tree rhs2) |
1553 | { | |
9908fe4d | 1554 | ccp_prop_value_t r1val = get_value_for_expr (rhs1, true); |
1555 | ccp_prop_value_t r2val = get_value_for_expr (rhs2, true); | |
5de9d3ed | 1556 | widest_int value, mask; |
9908fe4d | 1557 | ccp_prop_value_t val; |
c91fedc5 | 1558 | |
1559 | if (r1val.lattice_val == UNDEFINED | |
1560 | || r2val.lattice_val == UNDEFINED) | |
1561 | { | |
1562 | val.lattice_val = VARYING; | |
1563 | val.value = NULL_TREE; | |
e913b5cd | 1564 | val.mask = -1; |
c91fedc5 | 1565 | return val; |
1566 | } | |
1567 | ||
b7e55469 | 1568 | gcc_assert ((r1val.lattice_val == CONSTANT |
1569 | && TREE_CODE (r1val.value) == INTEGER_CST) | |
c90d2c17 | 1570 | || wi::sext (r1val.mask, |
1571 | TYPE_PRECISION (TREE_TYPE (rhs1))) == -1); | |
b7e55469 | 1572 | gcc_assert ((r2val.lattice_val == CONSTANT |
1573 | && TREE_CODE (r2val.value) == INTEGER_CST) | |
c90d2c17 | 1574 | || wi::sext (r2val.mask, |
1575 | TYPE_PRECISION (TREE_TYPE (rhs2))) == -1); | |
b7e55469 | 1576 | bit_value_binop_1 (code, type, &value, &mask, |
e913b5cd | 1577 | TREE_TYPE (rhs1), value_to_wide_int (r1val), r1val.mask, |
1578 | TREE_TYPE (rhs2), value_to_wide_int (r2val), r2val.mask); | |
c90d2c17 | 1579 | if (wi::sext (mask, TYPE_PRECISION (type)) != -1) |
b7e55469 | 1580 | { |
1581 | val.lattice_val = CONSTANT; | |
1582 | val.mask = mask; | |
1583 | /* ??? Delay building trees here. */ | |
e913b5cd | 1584 | val.value = wide_int_to_tree (type, value); |
b7e55469 | 1585 | } |
1586 | else | |
1587 | { | |
1588 | val.lattice_val = VARYING; | |
1589 | val.value = NULL_TREE; | |
e913b5cd | 1590 | val.mask = -1; |
b7e55469 | 1591 | } |
1592 | return val; | |
1593 | } | |
1594 | ||
237e78b1 | 1595 | /* Return the propagation value for __builtin_assume_aligned |
1596 | and functions with assume_aligned or alloc_aligned attribute. | |
1597 | For __builtin_assume_aligned, ATTR is NULL_TREE, | |
1598 | for assume_aligned attribute ATTR is non-NULL and ALLOC_ALIGNED | |
1599 | is false, for alloc_aligned attribute ATTR is non-NULL and | |
1600 | ALLOC_ALIGNED is true. */ | |
fca0886c | 1601 | |
9908fe4d | 1602 | static ccp_prop_value_t |
1603 | bit_value_assume_aligned (gimple stmt, tree attr, ccp_prop_value_t ptrval, | |
237e78b1 | 1604 | bool alloc_aligned) |
fca0886c | 1605 | { |
237e78b1 | 1606 | tree align, misalign = NULL_TREE, type; |
fca0886c | 1607 | unsigned HOST_WIDE_INT aligni, misaligni = 0; |
9908fe4d | 1608 | ccp_prop_value_t alignval; |
5de9d3ed | 1609 | widest_int value, mask; |
9908fe4d | 1610 | ccp_prop_value_t val; |
e913b5cd | 1611 | |
237e78b1 | 1612 | if (attr == NULL_TREE) |
1613 | { | |
1614 | tree ptr = gimple_call_arg (stmt, 0); | |
1615 | type = TREE_TYPE (ptr); | |
1616 | ptrval = get_value_for_expr (ptr, true); | |
1617 | } | |
1618 | else | |
1619 | { | |
1620 | tree lhs = gimple_call_lhs (stmt); | |
1621 | type = TREE_TYPE (lhs); | |
1622 | } | |
1623 | ||
fca0886c | 1624 | if (ptrval.lattice_val == UNDEFINED) |
1625 | return ptrval; | |
1626 | gcc_assert ((ptrval.lattice_val == CONSTANT | |
1627 | && TREE_CODE (ptrval.value) == INTEGER_CST) | |
c90d2c17 | 1628 | || wi::sext (ptrval.mask, TYPE_PRECISION (type)) == -1); |
237e78b1 | 1629 | if (attr == NULL_TREE) |
fca0886c | 1630 | { |
237e78b1 | 1631 | /* Get aligni and misaligni from __builtin_assume_aligned. */ |
1632 | align = gimple_call_arg (stmt, 1); | |
1633 | if (!tree_fits_uhwi_p (align)) | |
fca0886c | 1634 | return ptrval; |
237e78b1 | 1635 | aligni = tree_to_uhwi (align); |
1636 | if (gimple_call_num_args (stmt) > 2) | |
1637 | { | |
1638 | misalign = gimple_call_arg (stmt, 2); | |
1639 | if (!tree_fits_uhwi_p (misalign)) | |
1640 | return ptrval; | |
1641 | misaligni = tree_to_uhwi (misalign); | |
1642 | } | |
1643 | } | |
1644 | else | |
fca0886c | 1645 | { |
237e78b1 | 1646 | /* Get aligni and misaligni from assume_aligned or |
1647 | alloc_align attributes. */ | |
1648 | if (TREE_VALUE (attr) == NULL_TREE) | |
fca0886c | 1649 | return ptrval; |
237e78b1 | 1650 | attr = TREE_VALUE (attr); |
1651 | align = TREE_VALUE (attr); | |
1652 | if (!tree_fits_uhwi_p (align)) | |
fca0886c | 1653 | return ptrval; |
237e78b1 | 1654 | aligni = tree_to_uhwi (align); |
1655 | if (alloc_aligned) | |
1656 | { | |
1657 | if (aligni == 0 || aligni > gimple_call_num_args (stmt)) | |
1658 | return ptrval; | |
1659 | align = gimple_call_arg (stmt, aligni - 1); | |
1660 | if (!tree_fits_uhwi_p (align)) | |
1661 | return ptrval; | |
1662 | aligni = tree_to_uhwi (align); | |
1663 | } | |
1664 | else if (TREE_CHAIN (attr) && TREE_VALUE (TREE_CHAIN (attr))) | |
1665 | { | |
1666 | misalign = TREE_VALUE (TREE_CHAIN (attr)); | |
1667 | if (!tree_fits_uhwi_p (misalign)) | |
1668 | return ptrval; | |
1669 | misaligni = tree_to_uhwi (misalign); | |
1670 | } | |
fca0886c | 1671 | } |
237e78b1 | 1672 | if (aligni <= 1 || (aligni & (aligni - 1)) != 0 || misaligni >= aligni) |
1673 | return ptrval; | |
1674 | ||
fca0886c | 1675 | align = build_int_cst_type (type, -aligni); |
1676 | alignval = get_value_for_expr (align, true); | |
1677 | bit_value_binop_1 (BIT_AND_EXPR, type, &value, &mask, | |
e913b5cd | 1678 | type, value_to_wide_int (ptrval), ptrval.mask, |
1679 | type, value_to_wide_int (alignval), alignval.mask); | |
c90d2c17 | 1680 | if (wi::sext (mask, TYPE_PRECISION (type)) != -1) |
fca0886c | 1681 | { |
1682 | val.lattice_val = CONSTANT; | |
1683 | val.mask = mask; | |
e913b5cd | 1684 | gcc_assert ((mask.to_uhwi () & (aligni - 1)) == 0); |
1685 | gcc_assert ((value.to_uhwi () & (aligni - 1)) == 0); | |
1686 | value |= misaligni; | |
fca0886c | 1687 | /* ??? Delay building trees here. */ |
e913b5cd | 1688 | val.value = wide_int_to_tree (type, value); |
fca0886c | 1689 | } |
1690 | else | |
1691 | { | |
1692 | val.lattice_val = VARYING; | |
1693 | val.value = NULL_TREE; | |
e913b5cd | 1694 | val.mask = -1; |
fca0886c | 1695 | } |
1696 | return val; | |
1697 | } | |
1698 | ||
75a70cf9 | 1699 | /* Evaluate statement STMT. |
1700 | Valid only for assignments, calls, conditionals, and switches. */ | |
4ee9c684 | 1701 | |
9908fe4d | 1702 | static ccp_prop_value_t |
75a70cf9 | 1703 | evaluate_stmt (gimple stmt) |
4ee9c684 | 1704 | { |
9908fe4d | 1705 | ccp_prop_value_t val; |
4f61cce6 | 1706 | tree simplified = NULL_TREE; |
88dbf20f | 1707 | ccp_lattice_t likelyvalue = likely_value (stmt); |
b7e55469 | 1708 | bool is_constant = false; |
581bf1c2 | 1709 | unsigned int align; |
88dbf20f | 1710 | |
b7e55469 | 1711 | if (dump_file && (dump_flags & TDF_DETAILS)) |
1712 | { | |
1713 | fprintf (dump_file, "which is likely "); | |
1714 | switch (likelyvalue) | |
1715 | { | |
1716 | case CONSTANT: | |
1717 | fprintf (dump_file, "CONSTANT"); | |
1718 | break; | |
1719 | case UNDEFINED: | |
1720 | fprintf (dump_file, "UNDEFINED"); | |
1721 | break; | |
1722 | case VARYING: | |
1723 | fprintf (dump_file, "VARYING"); | |
1724 | break; | |
1725 | default:; | |
1726 | } | |
1727 | fprintf (dump_file, "\n"); | |
1728 | } | |
add6ee5e | 1729 | |
4ee9c684 | 1730 | /* If the statement is likely to have a CONSTANT result, then try |
1731 | to fold the statement to determine the constant value. */ | |
75a70cf9 | 1732 | /* FIXME. This is the only place that we call ccp_fold. |
1733 | Since likely_value never returns CONSTANT for calls, we will | |
1734 | not attempt to fold them, including builtins that may profit. */ | |
4ee9c684 | 1735 | if (likelyvalue == CONSTANT) |
b7e55469 | 1736 | { |
1737 | fold_defer_overflow_warnings (); | |
1738 | simplified = ccp_fold (stmt); | |
27de3d43 | 1739 | if (simplified && TREE_CODE (simplified) == SSA_NAME) |
1740 | { | |
1741 | val = *get_value (simplified); | |
1742 | if (val.lattice_val != VARYING) | |
1743 | { | |
1744 | fold_undefer_overflow_warnings (true, stmt, 0); | |
1745 | return val; | |
1746 | } | |
1747 | } | |
b7e55469 | 1748 | is_constant = simplified && is_gimple_min_invariant (simplified); |
1749 | fold_undefer_overflow_warnings (is_constant, stmt, 0); | |
1750 | if (is_constant) | |
1751 | { | |
1752 | /* The statement produced a constant value. */ | |
1753 | val.lattice_val = CONSTANT; | |
1754 | val.value = simplified; | |
e913b5cd | 1755 | val.mask = 0; |
27de3d43 | 1756 | return val; |
b7e55469 | 1757 | } |
1758 | } | |
4ee9c684 | 1759 | /* If the statement is likely to have a VARYING result, then do not |
1760 | bother folding the statement. */ | |
04236c3a | 1761 | else if (likelyvalue == VARYING) |
75a70cf9 | 1762 | { |
590c3166 | 1763 | enum gimple_code code = gimple_code (stmt); |
75a70cf9 | 1764 | if (code == GIMPLE_ASSIGN) |
1765 | { | |
1766 | enum tree_code subcode = gimple_assign_rhs_code (stmt); | |
48e1416a | 1767 | |
75a70cf9 | 1768 | /* Other cases cannot satisfy is_gimple_min_invariant |
1769 | without folding. */ | |
1770 | if (get_gimple_rhs_class (subcode) == GIMPLE_SINGLE_RHS) | |
1771 | simplified = gimple_assign_rhs1 (stmt); | |
1772 | } | |
1773 | else if (code == GIMPLE_SWITCH) | |
1a91d914 | 1774 | simplified = gimple_switch_index (as_a <gswitch *> (stmt)); |
75a70cf9 | 1775 | else |
a65c4d64 | 1776 | /* These cannot satisfy is_gimple_min_invariant without folding. */ |
1777 | gcc_assert (code == GIMPLE_CALL || code == GIMPLE_COND); | |
b7e55469 | 1778 | is_constant = simplified && is_gimple_min_invariant (simplified); |
1779 | if (is_constant) | |
1780 | { | |
1781 | /* The statement produced a constant value. */ | |
1782 | val.lattice_val = CONSTANT; | |
1783 | val.value = simplified; | |
e913b5cd | 1784 | val.mask = 0; |
b7e55469 | 1785 | } |
75a70cf9 | 1786 | } |
4c9206f2 | 1787 | /* If the statement result is likely UNDEFINED, make it so. */ |
1788 | else if (likelyvalue == UNDEFINED) | |
1789 | { | |
1790 | val.lattice_val = UNDEFINED; | |
1791 | val.value = NULL_TREE; | |
1792 | val.mask = 0; | |
1793 | return val; | |
1794 | } | |
4ee9c684 | 1795 | |
b7e55469 | 1796 | /* Resort to simplification for bitwise tracking. */ |
1797 | if (flag_tree_bit_ccp | |
db48deb0 | 1798 | && (likelyvalue == CONSTANT || is_gimple_call (stmt) |
1799 | || (gimple_assign_single_p (stmt) | |
1800 | && gimple_assign_rhs_code (stmt) == ADDR_EXPR)) | |
b7e55469 | 1801 | && !is_constant) |
912f109f | 1802 | { |
b7e55469 | 1803 | enum gimple_code code = gimple_code (stmt); |
1804 | val.lattice_val = VARYING; | |
1805 | val.value = NULL_TREE; | |
e913b5cd | 1806 | val.mask = -1; |
b7e55469 | 1807 | if (code == GIMPLE_ASSIGN) |
912f109f | 1808 | { |
b7e55469 | 1809 | enum tree_code subcode = gimple_assign_rhs_code (stmt); |
1810 | tree rhs1 = gimple_assign_rhs1 (stmt); | |
c0a4b664 | 1811 | tree lhs = gimple_assign_lhs (stmt); |
1812 | if ((INTEGRAL_TYPE_P (TREE_TYPE (lhs)) | |
1813 | || POINTER_TYPE_P (TREE_TYPE (lhs))) | |
1814 | && (INTEGRAL_TYPE_P (TREE_TYPE (rhs1)) | |
1815 | || POINTER_TYPE_P (TREE_TYPE (rhs1)))) | |
1816 | switch (get_gimple_rhs_class (subcode)) | |
1817 | { | |
1818 | case GIMPLE_SINGLE_RHS: | |
1819 | val = get_value_for_expr (rhs1, true); | |
1820 | break; | |
1821 | ||
1822 | case GIMPLE_UNARY_RHS: | |
1823 | val = bit_value_unop (subcode, TREE_TYPE (lhs), rhs1); | |
1824 | break; | |
1825 | ||
1826 | case GIMPLE_BINARY_RHS: | |
1827 | val = bit_value_binop (subcode, TREE_TYPE (lhs), rhs1, | |
1828 | gimple_assign_rhs2 (stmt)); | |
1829 | break; | |
1830 | ||
1831 | default:; | |
1832 | } | |
912f109f | 1833 | } |
b7e55469 | 1834 | else if (code == GIMPLE_COND) |
1835 | { | |
1836 | enum tree_code code = gimple_cond_code (stmt); | |
1837 | tree rhs1 = gimple_cond_lhs (stmt); | |
1838 | tree rhs2 = gimple_cond_rhs (stmt); | |
1839 | if (INTEGRAL_TYPE_P (TREE_TYPE (rhs1)) | |
1840 | || POINTER_TYPE_P (TREE_TYPE (rhs1))) | |
1841 | val = bit_value_binop (code, TREE_TYPE (rhs1), rhs1, rhs2); | |
1842 | } | |
0b4f0116 | 1843 | else if (gimple_call_builtin_p (stmt, BUILT_IN_NORMAL)) |
153c3b50 | 1844 | { |
0b4f0116 | 1845 | tree fndecl = gimple_call_fndecl (stmt); |
153c3b50 | 1846 | switch (DECL_FUNCTION_CODE (fndecl)) |
1847 | { | |
1848 | case BUILT_IN_MALLOC: | |
1849 | case BUILT_IN_REALLOC: | |
1850 | case BUILT_IN_CALLOC: | |
939514e9 | 1851 | case BUILT_IN_STRDUP: |
1852 | case BUILT_IN_STRNDUP: | |
153c3b50 | 1853 | val.lattice_val = CONSTANT; |
1854 | val.value = build_int_cst (TREE_TYPE (gimple_get_lhs (stmt)), 0); | |
796b6678 | 1855 | val.mask = ~((HOST_WIDE_INT) MALLOC_ABI_ALIGNMENT |
1856 | / BITS_PER_UNIT - 1); | |
153c3b50 | 1857 | break; |
1858 | ||
1859 | case BUILT_IN_ALLOCA: | |
581bf1c2 | 1860 | case BUILT_IN_ALLOCA_WITH_ALIGN: |
1861 | align = (DECL_FUNCTION_CODE (fndecl) == BUILT_IN_ALLOCA_WITH_ALIGN | |
f9ae6f95 | 1862 | ? TREE_INT_CST_LOW (gimple_call_arg (stmt, 1)) |
581bf1c2 | 1863 | : BIGGEST_ALIGNMENT); |
153c3b50 | 1864 | val.lattice_val = CONSTANT; |
1865 | val.value = build_int_cst (TREE_TYPE (gimple_get_lhs (stmt)), 0); | |
796b6678 | 1866 | val.mask = ~((HOST_WIDE_INT) align / BITS_PER_UNIT - 1); |
153c3b50 | 1867 | break; |
1868 | ||
939514e9 | 1869 | /* These builtins return their first argument, unmodified. */ |
1870 | case BUILT_IN_MEMCPY: | |
1871 | case BUILT_IN_MEMMOVE: | |
1872 | case BUILT_IN_MEMSET: | |
1873 | case BUILT_IN_STRCPY: | |
1874 | case BUILT_IN_STRNCPY: | |
1875 | case BUILT_IN_MEMCPY_CHK: | |
1876 | case BUILT_IN_MEMMOVE_CHK: | |
1877 | case BUILT_IN_MEMSET_CHK: | |
1878 | case BUILT_IN_STRCPY_CHK: | |
1879 | case BUILT_IN_STRNCPY_CHK: | |
1880 | val = get_value_for_expr (gimple_call_arg (stmt, 0), true); | |
1881 | break; | |
1882 | ||
fca0886c | 1883 | case BUILT_IN_ASSUME_ALIGNED: |
237e78b1 | 1884 | val = bit_value_assume_aligned (stmt, NULL_TREE, val, false); |
fca0886c | 1885 | break; |
1886 | ||
060fc206 | 1887 | case BUILT_IN_ALIGNED_ALLOC: |
1888 | { | |
1889 | tree align = get_constant_value (gimple_call_arg (stmt, 0)); | |
1890 | if (align | |
1891 | && tree_fits_uhwi_p (align)) | |
1892 | { | |
1893 | unsigned HOST_WIDE_INT aligni = tree_to_uhwi (align); | |
1894 | if (aligni > 1 | |
1895 | /* align must be power-of-two */ | |
1896 | && (aligni & (aligni - 1)) == 0) | |
1897 | { | |
1898 | val.lattice_val = CONSTANT; | |
1899 | val.value = build_int_cst (ptr_type_node, 0); | |
cd89b631 | 1900 | val.mask = -aligni; |
060fc206 | 1901 | } |
1902 | } | |
1903 | break; | |
1904 | } | |
1905 | ||
153c3b50 | 1906 | default:; |
1907 | } | |
1908 | } | |
237e78b1 | 1909 | if (is_gimple_call (stmt) && gimple_call_lhs (stmt)) |
1910 | { | |
1911 | tree fntype = gimple_call_fntype (stmt); | |
1912 | if (fntype) | |
1913 | { | |
1914 | tree attrs = lookup_attribute ("assume_aligned", | |
1915 | TYPE_ATTRIBUTES (fntype)); | |
1916 | if (attrs) | |
1917 | val = bit_value_assume_aligned (stmt, attrs, val, false); | |
1918 | attrs = lookup_attribute ("alloc_align", | |
1919 | TYPE_ATTRIBUTES (fntype)); | |
1920 | if (attrs) | |
1921 | val = bit_value_assume_aligned (stmt, attrs, val, true); | |
1922 | } | |
1923 | } | |
b7e55469 | 1924 | is_constant = (val.lattice_val == CONSTANT); |
912f109f | 1925 | } |
1926 | ||
fc08b993 | 1927 | if (flag_tree_bit_ccp |
1928 | && ((is_constant && TREE_CODE (val.value) == INTEGER_CST) | |
4c9206f2 | 1929 | || !is_constant) |
fc08b993 | 1930 | && gimple_get_lhs (stmt) |
1931 | && TREE_CODE (gimple_get_lhs (stmt)) == SSA_NAME) | |
1932 | { | |
1933 | tree lhs = gimple_get_lhs (stmt); | |
9c1be15e | 1934 | wide_int nonzero_bits = get_nonzero_bits (lhs); |
1935 | if (nonzero_bits != -1) | |
fc08b993 | 1936 | { |
1937 | if (!is_constant) | |
1938 | { | |
1939 | val.lattice_val = CONSTANT; | |
1940 | val.value = build_zero_cst (TREE_TYPE (lhs)); | |
9c1be15e | 1941 | val.mask = extend_mask (nonzero_bits); |
fc08b993 | 1942 | is_constant = true; |
1943 | } | |
1944 | else | |
1945 | { | |
9c1be15e | 1946 | if (wi::bit_and_not (val.value, nonzero_bits) != 0) |
aeb682a2 | 1947 | val.value = wide_int_to_tree (TREE_TYPE (lhs), |
9c1be15e | 1948 | nonzero_bits & val.value); |
aeb682a2 | 1949 | if (nonzero_bits == 0) |
1950 | val.mask = 0; | |
fc08b993 | 1951 | else |
09b2913a | 1952 | val.mask = val.mask & extend_mask (nonzero_bits); |
fc08b993 | 1953 | } |
1954 | } | |
1955 | } | |
1956 | ||
4c9206f2 | 1957 | /* The statement produced a nonconstant value. */ |
b7e55469 | 1958 | if (!is_constant) |
4ee9c684 | 1959 | { |
fc6cc27b | 1960 | /* The statement produced a copy. */ |
1961 | if (simplified && TREE_CODE (simplified) == SSA_NAME | |
1962 | && !SSA_NAME_OCCURS_IN_ABNORMAL_PHI (simplified)) | |
1963 | { | |
1964 | val.lattice_val = CONSTANT; | |
1965 | val.value = simplified; | |
1966 | val.mask = -1; | |
1967 | } | |
1968 | /* The statement is VARYING. */ | |
1969 | else | |
1970 | { | |
1971 | val.lattice_val = VARYING; | |
1972 | val.value = NULL_TREE; | |
1973 | val.mask = -1; | |
1974 | } | |
4ee9c684 | 1975 | } |
41511585 | 1976 | |
1977 | return val; | |
4ee9c684 | 1978 | } |
1979 | ||
770ff93b | 1980 | typedef hash_table<nofree_ptr_hash<gimple_statement_base> > gimple_htab; |
2b15d2ba | 1981 | |
582a80ed | 1982 | /* Given a BUILT_IN_STACK_SAVE value SAVED_VAL, insert a clobber of VAR before |
1983 | each matching BUILT_IN_STACK_RESTORE. Mark visited phis in VISITED. */ | |
1984 | ||
1985 | static void | |
2b15d2ba | 1986 | insert_clobber_before_stack_restore (tree saved_val, tree var, |
c1f445d2 | 1987 | gimple_htab **visited) |
582a80ed | 1988 | { |
1a91d914 | 1989 | gimple stmt; |
1990 | gassign *clobber_stmt; | |
582a80ed | 1991 | tree clobber; |
1992 | imm_use_iterator iter; | |
1993 | gimple_stmt_iterator i; | |
1994 | gimple *slot; | |
1995 | ||
1996 | FOR_EACH_IMM_USE_STMT (stmt, iter, saved_val) | |
1997 | if (gimple_call_builtin_p (stmt, BUILT_IN_STACK_RESTORE)) | |
1998 | { | |
f1f41a6c | 1999 | clobber = build_constructor (TREE_TYPE (var), |
2000 | NULL); | |
582a80ed | 2001 | TREE_THIS_VOLATILE (clobber) = 1; |
2002 | clobber_stmt = gimple_build_assign (var, clobber); | |
2003 | ||
2004 | i = gsi_for_stmt (stmt); | |
2005 | gsi_insert_before (&i, clobber_stmt, GSI_SAME_STMT); | |
2006 | } | |
2007 | else if (gimple_code (stmt) == GIMPLE_PHI) | |
2008 | { | |
c1f445d2 | 2009 | if (!*visited) |
2010 | *visited = new gimple_htab (10); | |
582a80ed | 2011 | |
c1f445d2 | 2012 | slot = (*visited)->find_slot (stmt, INSERT); |
582a80ed | 2013 | if (*slot != NULL) |
2014 | continue; | |
2015 | ||
2016 | *slot = stmt; | |
2017 | insert_clobber_before_stack_restore (gimple_phi_result (stmt), var, | |
2018 | visited); | |
2019 | } | |
42eed683 | 2020 | else if (gimple_assign_ssa_name_copy_p (stmt)) |
2021 | insert_clobber_before_stack_restore (gimple_assign_lhs (stmt), var, | |
2022 | visited); | |
058a1b7a | 2023 | else if (chkp_gimple_call_builtin_p (stmt, BUILT_IN_CHKP_BNDRET)) |
2024 | continue; | |
582a80ed | 2025 | else |
2026 | gcc_assert (is_gimple_debug (stmt)); | |
2027 | } | |
2028 | ||
2029 | /* Advance the iterator to the previous non-debug gimple statement in the same | |
2030 | or dominating basic block. */ | |
2031 | ||
2032 | static inline void | |
2033 | gsi_prev_dom_bb_nondebug (gimple_stmt_iterator *i) | |
2034 | { | |
2035 | basic_block dom; | |
2036 | ||
2037 | gsi_prev_nondebug (i); | |
2038 | while (gsi_end_p (*i)) | |
2039 | { | |
2040 | dom = get_immediate_dominator (CDI_DOMINATORS, i->bb); | |
34154e27 | 2041 | if (dom == NULL || dom == ENTRY_BLOCK_PTR_FOR_FN (cfun)) |
582a80ed | 2042 | return; |
2043 | ||
2044 | *i = gsi_last_bb (dom); | |
2045 | } | |
2046 | } | |
2047 | ||
2048 | /* Find a BUILT_IN_STACK_SAVE dominating gsi_stmt (I), and insert | |
1543f720 | 2049 | a clobber of VAR before each matching BUILT_IN_STACK_RESTORE. |
2050 | ||
2051 | It is possible that BUILT_IN_STACK_SAVE cannot be find in a dominator when a | |
2052 | previous pass (such as DOM) duplicated it along multiple paths to a BB. In | |
2053 | that case the function gives up without inserting the clobbers. */ | |
582a80ed | 2054 | |
2055 | static void | |
2056 | insert_clobbers_for_var (gimple_stmt_iterator i, tree var) | |
2057 | { | |
582a80ed | 2058 | gimple stmt; |
2059 | tree saved_val; | |
c1f445d2 | 2060 | gimple_htab *visited = NULL; |
582a80ed | 2061 | |
1543f720 | 2062 | for (; !gsi_end_p (i); gsi_prev_dom_bb_nondebug (&i)) |
582a80ed | 2063 | { |
2064 | stmt = gsi_stmt (i); | |
2065 | ||
2066 | if (!gimple_call_builtin_p (stmt, BUILT_IN_STACK_SAVE)) | |
2067 | continue; | |
582a80ed | 2068 | |
2069 | saved_val = gimple_call_lhs (stmt); | |
2070 | if (saved_val == NULL_TREE) | |
2071 | continue; | |
2072 | ||
2073 | insert_clobber_before_stack_restore (saved_val, var, &visited); | |
2074 | break; | |
2075 | } | |
2076 | ||
c1f445d2 | 2077 | delete visited; |
582a80ed | 2078 | } |
2079 | ||
581bf1c2 | 2080 | /* Detects a __builtin_alloca_with_align with constant size argument. Declares |
2081 | fixed-size array and returns the address, if found, otherwise returns | |
2082 | NULL_TREE. */ | |
9a65cc0a | 2083 | |
2084 | static tree | |
581bf1c2 | 2085 | fold_builtin_alloca_with_align (gimple stmt) |
9a65cc0a | 2086 | { |
2087 | unsigned HOST_WIDE_INT size, threshold, n_elem; | |
2088 | tree lhs, arg, block, var, elem_type, array_type; | |
9a65cc0a | 2089 | |
2090 | /* Get lhs. */ | |
2091 | lhs = gimple_call_lhs (stmt); | |
2092 | if (lhs == NULL_TREE) | |
2093 | return NULL_TREE; | |
2094 | ||
2095 | /* Detect constant argument. */ | |
2096 | arg = get_constant_value (gimple_call_arg (stmt, 0)); | |
6e93d308 | 2097 | if (arg == NULL_TREE |
2098 | || TREE_CODE (arg) != INTEGER_CST | |
e913b5cd | 2099 | || !tree_fits_uhwi_p (arg)) |
9a65cc0a | 2100 | return NULL_TREE; |
6e93d308 | 2101 | |
8c53c46c | 2102 | size = tree_to_uhwi (arg); |
9a65cc0a | 2103 | |
581bf1c2 | 2104 | /* Heuristic: don't fold large allocas. */ |
9a65cc0a | 2105 | threshold = (unsigned HOST_WIDE_INT)PARAM_VALUE (PARAM_LARGE_STACK_FRAME); |
581bf1c2 | 2106 | /* In case the alloca is located at function entry, it has the same lifetime |
2107 | as a declared array, so we allow a larger size. */ | |
9a65cc0a | 2108 | block = gimple_block (stmt); |
2109 | if (!(cfun->after_inlining | |
2110 | && TREE_CODE (BLOCK_SUPERCONTEXT (block)) == FUNCTION_DECL)) | |
2111 | threshold /= 10; | |
2112 | if (size > threshold) | |
2113 | return NULL_TREE; | |
2114 | ||
2115 | /* Declare array. */ | |
2116 | elem_type = build_nonstandard_integer_type (BITS_PER_UNIT, 1); | |
2117 | n_elem = size * 8 / BITS_PER_UNIT; | |
9a65cc0a | 2118 | array_type = build_array_type_nelts (elem_type, n_elem); |
f9e245b2 | 2119 | var = create_tmp_var (array_type); |
f9ae6f95 | 2120 | DECL_ALIGN (var) = TREE_INT_CST_LOW (gimple_call_arg (stmt, 1)); |
3d4a0a4b | 2121 | { |
2122 | struct ptr_info_def *pi = SSA_NAME_PTR_INFO (lhs); | |
2123 | if (pi != NULL && !pi->pt.anything) | |
2124 | { | |
2125 | bool singleton_p; | |
2126 | unsigned uid; | |
2127 | singleton_p = pt_solution_singleton_p (&pi->pt, &uid); | |
2128 | gcc_assert (singleton_p); | |
2129 | SET_DECL_PT_UID (var, uid); | |
2130 | } | |
2131 | } | |
9a65cc0a | 2132 | |
2133 | /* Fold alloca to the address of the array. */ | |
2134 | return fold_convert (TREE_TYPE (lhs), build_fold_addr_expr (var)); | |
2135 | } | |
2136 | ||
6688f8ec | 2137 | /* Fold the stmt at *GSI with CCP specific information that propagating |
2138 | and regular folding does not catch. */ | |
2139 | ||
2140 | static bool | |
2141 | ccp_fold_stmt (gimple_stmt_iterator *gsi) | |
2142 | { | |
2143 | gimple stmt = gsi_stmt (*gsi); | |
6688f8ec | 2144 | |
94144e68 | 2145 | switch (gimple_code (stmt)) |
2146 | { | |
2147 | case GIMPLE_COND: | |
2148 | { | |
1a91d914 | 2149 | gcond *cond_stmt = as_a <gcond *> (stmt); |
9908fe4d | 2150 | ccp_prop_value_t val; |
94144e68 | 2151 | /* Statement evaluation will handle type mismatches in constants |
2152 | more gracefully than the final propagation. This allows us to | |
2153 | fold more conditionals here. */ | |
2154 | val = evaluate_stmt (stmt); | |
2155 | if (val.lattice_val != CONSTANT | |
796b6678 | 2156 | || val.mask != 0) |
94144e68 | 2157 | return false; |
2158 | ||
b7e55469 | 2159 | if (dump_file) |
2160 | { | |
2161 | fprintf (dump_file, "Folding predicate "); | |
2162 | print_gimple_expr (dump_file, stmt, 0, 0); | |
2163 | fprintf (dump_file, " to "); | |
2164 | print_generic_expr (dump_file, val.value, 0); | |
2165 | fprintf (dump_file, "\n"); | |
2166 | } | |
2167 | ||
94144e68 | 2168 | if (integer_zerop (val.value)) |
1a91d914 | 2169 | gimple_cond_make_false (cond_stmt); |
94144e68 | 2170 | else |
1a91d914 | 2171 | gimple_cond_make_true (cond_stmt); |
6688f8ec | 2172 | |
94144e68 | 2173 | return true; |
2174 | } | |
6688f8ec | 2175 | |
94144e68 | 2176 | case GIMPLE_CALL: |
2177 | { | |
2178 | tree lhs = gimple_call_lhs (stmt); | |
3064bb7b | 2179 | int flags = gimple_call_flags (stmt); |
15d138c9 | 2180 | tree val; |
94144e68 | 2181 | tree argt; |
2182 | bool changed = false; | |
2183 | unsigned i; | |
2184 | ||
2185 | /* If the call was folded into a constant make sure it goes | |
2186 | away even if we cannot propagate into all uses because of | |
2187 | type issues. */ | |
2188 | if (lhs | |
2189 | && TREE_CODE (lhs) == SSA_NAME | |
3064bb7b | 2190 | && (val = get_constant_value (lhs)) |
2191 | /* Don't optimize away calls that have side-effects. */ | |
2192 | && (flags & (ECF_CONST|ECF_PURE)) != 0 | |
2193 | && (flags & ECF_LOOPING_CONST_OR_PURE) == 0) | |
94144e68 | 2194 | { |
15d138c9 | 2195 | tree new_rhs = unshare_expr (val); |
338cce8f | 2196 | bool res; |
94144e68 | 2197 | if (!useless_type_conversion_p (TREE_TYPE (lhs), |
2198 | TREE_TYPE (new_rhs))) | |
2199 | new_rhs = fold_convert (TREE_TYPE (lhs), new_rhs); | |
338cce8f | 2200 | res = update_call_from_tree (gsi, new_rhs); |
2201 | gcc_assert (res); | |
94144e68 | 2202 | return true; |
2203 | } | |
2204 | ||
fb049fba | 2205 | /* Internal calls provide no argument types, so the extra laxity |
2206 | for normal calls does not apply. */ | |
2207 | if (gimple_call_internal_p (stmt)) | |
2208 | return false; | |
2209 | ||
581bf1c2 | 2210 | /* The heuristic of fold_builtin_alloca_with_align differs before and |
2211 | after inlining, so we don't require the arg to be changed into a | |
2212 | constant for folding, but just to be constant. */ | |
2213 | if (gimple_call_builtin_p (stmt, BUILT_IN_ALLOCA_WITH_ALIGN)) | |
9a65cc0a | 2214 | { |
581bf1c2 | 2215 | tree new_rhs = fold_builtin_alloca_with_align (stmt); |
6e93d308 | 2216 | if (new_rhs) |
2217 | { | |
2218 | bool res = update_call_from_tree (gsi, new_rhs); | |
582a80ed | 2219 | tree var = TREE_OPERAND (TREE_OPERAND (new_rhs, 0),0); |
6e93d308 | 2220 | gcc_assert (res); |
582a80ed | 2221 | insert_clobbers_for_var (*gsi, var); |
6e93d308 | 2222 | return true; |
2223 | } | |
9a65cc0a | 2224 | } |
2225 | ||
94144e68 | 2226 | /* Propagate into the call arguments. Compared to replace_uses_in |
2227 | this can use the argument slot types for type verification | |
2228 | instead of the current argument type. We also can safely | |
2229 | drop qualifiers here as we are dealing with constants anyway. */ | |
2de00a2d | 2230 | argt = TYPE_ARG_TYPES (gimple_call_fntype (stmt)); |
94144e68 | 2231 | for (i = 0; i < gimple_call_num_args (stmt) && argt; |
2232 | ++i, argt = TREE_CHAIN (argt)) | |
2233 | { | |
2234 | tree arg = gimple_call_arg (stmt, i); | |
2235 | if (TREE_CODE (arg) == SSA_NAME | |
15d138c9 | 2236 | && (val = get_constant_value (arg)) |
94144e68 | 2237 | && useless_type_conversion_p |
2238 | (TYPE_MAIN_VARIANT (TREE_VALUE (argt)), | |
15d138c9 | 2239 | TYPE_MAIN_VARIANT (TREE_TYPE (val)))) |
94144e68 | 2240 | { |
15d138c9 | 2241 | gimple_call_set_arg (stmt, i, unshare_expr (val)); |
94144e68 | 2242 | changed = true; |
2243 | } | |
2244 | } | |
e16f4c39 | 2245 | |
94144e68 | 2246 | return changed; |
2247 | } | |
6688f8ec | 2248 | |
6872bf3c | 2249 | case GIMPLE_ASSIGN: |
2250 | { | |
2251 | tree lhs = gimple_assign_lhs (stmt); | |
15d138c9 | 2252 | tree val; |
6872bf3c | 2253 | |
2254 | /* If we have a load that turned out to be constant replace it | |
2255 | as we cannot propagate into all uses in all cases. */ | |
2256 | if (gimple_assign_single_p (stmt) | |
2257 | && TREE_CODE (lhs) == SSA_NAME | |
15d138c9 | 2258 | && (val = get_constant_value (lhs))) |
6872bf3c | 2259 | { |
15d138c9 | 2260 | tree rhs = unshare_expr (val); |
6872bf3c | 2261 | if (!useless_type_conversion_p (TREE_TYPE (lhs), TREE_TYPE (rhs))) |
182cf5a9 | 2262 | rhs = fold_build1 (VIEW_CONVERT_EXPR, TREE_TYPE (lhs), rhs); |
6872bf3c | 2263 | gimple_assign_set_rhs_from_tree (gsi, rhs); |
2264 | return true; | |
2265 | } | |
2266 | ||
2267 | return false; | |
2268 | } | |
2269 | ||
94144e68 | 2270 | default: |
2271 | return false; | |
2272 | } | |
6688f8ec | 2273 | } |
2274 | ||
41511585 | 2275 | /* Visit the assignment statement STMT. Set the value of its LHS to the |
88dbf20f | 2276 | value computed by the RHS and store LHS in *OUTPUT_P. If STMT |
2277 | creates virtual definitions, set the value of each new name to that | |
75a70cf9 | 2278 | of the RHS (if we can derive a constant out of the RHS). |
2279 | Value-returning call statements also perform an assignment, and | |
2280 | are handled here. */ | |
4ee9c684 | 2281 | |
41511585 | 2282 | static enum ssa_prop_result |
75a70cf9 | 2283 | visit_assignment (gimple stmt, tree *output_p) |
4ee9c684 | 2284 | { |
9908fe4d | 2285 | ccp_prop_value_t val; |
fc6cc27b | 2286 | enum ssa_prop_result retval = SSA_PROP_NOT_INTERESTING; |
4ee9c684 | 2287 | |
75a70cf9 | 2288 | tree lhs = gimple_get_lhs (stmt); |
88dbf20f | 2289 | if (TREE_CODE (lhs) == SSA_NAME) |
4ee9c684 | 2290 | { |
fc6cc27b | 2291 | /* Evaluate the statement, which could be |
2292 | either a GIMPLE_ASSIGN or a GIMPLE_CALL. */ | |
2293 | val = evaluate_stmt (stmt); | |
2294 | ||
88dbf20f | 2295 | /* If STMT is an assignment to an SSA_NAME, we only have one |
2296 | value to set. */ | |
27de3d43 | 2297 | if (set_lattice_value (lhs, &val)) |
88dbf20f | 2298 | { |
2299 | *output_p = lhs; | |
2300 | if (val.lattice_val == VARYING) | |
2301 | retval = SSA_PROP_VARYING; | |
2302 | else | |
2303 | retval = SSA_PROP_INTERESTING; | |
2304 | } | |
4ee9c684 | 2305 | } |
88dbf20f | 2306 | |
2307 | return retval; | |
4ee9c684 | 2308 | } |
2309 | ||
4ee9c684 | 2310 | |
41511585 | 2311 | /* Visit the conditional statement STMT. Return SSA_PROP_INTERESTING |
2312 | if it can determine which edge will be taken. Otherwise, return | |
2313 | SSA_PROP_VARYING. */ | |
2314 | ||
2315 | static enum ssa_prop_result | |
75a70cf9 | 2316 | visit_cond_stmt (gimple stmt, edge *taken_edge_p) |
4ee9c684 | 2317 | { |
9908fe4d | 2318 | ccp_prop_value_t val; |
41511585 | 2319 | basic_block block; |
2320 | ||
75a70cf9 | 2321 | block = gimple_bb (stmt); |
41511585 | 2322 | val = evaluate_stmt (stmt); |
b7e55469 | 2323 | if (val.lattice_val != CONSTANT |
796b6678 | 2324 | || val.mask != 0) |
b7e55469 | 2325 | return SSA_PROP_VARYING; |
41511585 | 2326 | |
2327 | /* Find which edge out of the conditional block will be taken and add it | |
2328 | to the worklist. If no single edge can be determined statically, | |
2329 | return SSA_PROP_VARYING to feed all the outgoing edges to the | |
2330 | propagation engine. */ | |
b7e55469 | 2331 | *taken_edge_p = find_taken_edge (block, val.value); |
41511585 | 2332 | if (*taken_edge_p) |
2333 | return SSA_PROP_INTERESTING; | |
2334 | else | |
2335 | return SSA_PROP_VARYING; | |
4ee9c684 | 2336 | } |
2337 | ||
4ee9c684 | 2338 | |
41511585 | 2339 | /* Evaluate statement STMT. If the statement produces an output value and |
2340 | its evaluation changes the lattice value of its output, return | |
2341 | SSA_PROP_INTERESTING and set *OUTPUT_P to the SSA_NAME holding the | |
2342 | output value. | |
48e1416a | 2343 | |
41511585 | 2344 | If STMT is a conditional branch and we can determine its truth |
2345 | value, set *TAKEN_EDGE_P accordingly. If STMT produces a varying | |
2346 | value, return SSA_PROP_VARYING. */ | |
4ee9c684 | 2347 | |
41511585 | 2348 | static enum ssa_prop_result |
75a70cf9 | 2349 | ccp_visit_stmt (gimple stmt, edge *taken_edge_p, tree *output_p) |
41511585 | 2350 | { |
41511585 | 2351 | tree def; |
2352 | ssa_op_iter iter; | |
4ee9c684 | 2353 | |
41511585 | 2354 | if (dump_file && (dump_flags & TDF_DETAILS)) |
4ee9c684 | 2355 | { |
88dbf20f | 2356 | fprintf (dump_file, "\nVisiting statement:\n"); |
75a70cf9 | 2357 | print_gimple_stmt (dump_file, stmt, 0, dump_flags); |
4ee9c684 | 2358 | } |
4ee9c684 | 2359 | |
75a70cf9 | 2360 | switch (gimple_code (stmt)) |
4ee9c684 | 2361 | { |
75a70cf9 | 2362 | case GIMPLE_ASSIGN: |
2363 | /* If the statement is an assignment that produces a single | |
2364 | output value, evaluate its RHS to see if the lattice value of | |
2365 | its output has changed. */ | |
2366 | return visit_assignment (stmt, output_p); | |
2367 | ||
2368 | case GIMPLE_CALL: | |
2369 | /* A value-returning call also performs an assignment. */ | |
2370 | if (gimple_call_lhs (stmt) != NULL_TREE) | |
2371 | return visit_assignment (stmt, output_p); | |
2372 | break; | |
2373 | ||
2374 | case GIMPLE_COND: | |
2375 | case GIMPLE_SWITCH: | |
2376 | /* If STMT is a conditional branch, see if we can determine | |
2377 | which branch will be taken. */ | |
2378 | /* FIXME. It appears that we should be able to optimize | |
2379 | computed GOTOs here as well. */ | |
2380 | return visit_cond_stmt (stmt, taken_edge_p); | |
2381 | ||
2382 | default: | |
2383 | break; | |
4ee9c684 | 2384 | } |
4ee9c684 | 2385 | |
41511585 | 2386 | /* Any other kind of statement is not interesting for constant |
2387 | propagation and, therefore, not worth simulating. */ | |
41511585 | 2388 | if (dump_file && (dump_flags & TDF_DETAILS)) |
2389 | fprintf (dump_file, "No interesting values produced. Marked VARYING.\n"); | |
4ee9c684 | 2390 | |
41511585 | 2391 | /* Definitions made by statements other than assignments to |
2392 | SSA_NAMEs represent unknown modifications to their outputs. | |
2393 | Mark them VARYING. */ | |
88dbf20f | 2394 | FOR_EACH_SSA_TREE_OPERAND (def, stmt, iter, SSA_OP_ALL_DEFS) |
27de3d43 | 2395 | set_value_varying (def); |
4ee9c684 | 2396 | |
41511585 | 2397 | return SSA_PROP_VARYING; |
2398 | } | |
4ee9c684 | 2399 | |
4ee9c684 | 2400 | |
88dbf20f | 2401 | /* Main entry point for SSA Conditional Constant Propagation. */ |
41511585 | 2402 | |
33a34f1e | 2403 | static unsigned int |
61207d43 | 2404 | do_ssa_ccp (void) |
41511585 | 2405 | { |
582a80ed | 2406 | unsigned int todo = 0; |
2407 | calculate_dominance_info (CDI_DOMINATORS); | |
41511585 | 2408 | ccp_initialize (); |
2409 | ssa_propagate (ccp_visit_stmt, ccp_visit_phi_node); | |
33a34f1e | 2410 | if (ccp_finalize ()) |
560965e9 | 2411 | todo = (TODO_cleanup_cfg | TODO_update_ssa); |
582a80ed | 2412 | free_dominance_info (CDI_DOMINATORS); |
2413 | return todo; | |
4ee9c684 | 2414 | } |
2415 | ||
5664499b | 2416 | |
cbe8bda8 | 2417 | namespace { |
2418 | ||
2419 | const pass_data pass_data_ccp = | |
41511585 | 2420 | { |
cbe8bda8 | 2421 | GIMPLE_PASS, /* type */ |
2422 | "ccp", /* name */ | |
2423 | OPTGROUP_NONE, /* optinfo_flags */ | |
cbe8bda8 | 2424 | TV_TREE_CCP, /* tv_id */ |
2425 | ( PROP_cfg | PROP_ssa ), /* properties_required */ | |
2426 | 0, /* properties_provided */ | |
2427 | 0, /* properties_destroyed */ | |
2428 | 0, /* todo_flags_start */ | |
8b88439e | 2429 | TODO_update_address_taken, /* todo_flags_finish */ |
41511585 | 2430 | }; |
4ee9c684 | 2431 | |
cbe8bda8 | 2432 | class pass_ccp : public gimple_opt_pass |
2433 | { | |
2434 | public: | |
9af5ce0c | 2435 | pass_ccp (gcc::context *ctxt) |
2436 | : gimple_opt_pass (pass_data_ccp, ctxt) | |
cbe8bda8 | 2437 | {} |
2438 | ||
2439 | /* opt_pass methods: */ | |
ae84f584 | 2440 | opt_pass * clone () { return new pass_ccp (m_ctxt); } |
31315c24 | 2441 | virtual bool gate (function *) { return flag_tree_ccp != 0; } |
65b0537f | 2442 | virtual unsigned int execute (function *) { return do_ssa_ccp (); } |
cbe8bda8 | 2443 | |
2444 | }; // class pass_ccp | |
2445 | ||
2446 | } // anon namespace | |
2447 | ||
2448 | gimple_opt_pass * | |
2449 | make_pass_ccp (gcc::context *ctxt) | |
2450 | { | |
2451 | return new pass_ccp (ctxt); | |
2452 | } | |
2453 | ||
4ee9c684 | 2454 | |
75a70cf9 | 2455 | |
bdd0e199 | 2456 | /* Try to optimize out __builtin_stack_restore. Optimize it out |
2457 | if there is another __builtin_stack_restore in the same basic | |
2458 | block and no calls or ASM_EXPRs are in between, or if this block's | |
2459 | only outgoing edge is to EXIT_BLOCK and there are no calls or | |
2460 | ASM_EXPRs after this __builtin_stack_restore. */ | |
2461 | ||
2462 | static tree | |
75a70cf9 | 2463 | optimize_stack_restore (gimple_stmt_iterator i) |
bdd0e199 | 2464 | { |
6ea999da | 2465 | tree callee; |
2466 | gimple stmt; | |
75a70cf9 | 2467 | |
2468 | basic_block bb = gsi_bb (i); | |
2469 | gimple call = gsi_stmt (i); | |
bdd0e199 | 2470 | |
75a70cf9 | 2471 | if (gimple_code (call) != GIMPLE_CALL |
2472 | || gimple_call_num_args (call) != 1 | |
2473 | || TREE_CODE (gimple_call_arg (call, 0)) != SSA_NAME | |
2474 | || !POINTER_TYPE_P (TREE_TYPE (gimple_call_arg (call, 0)))) | |
bdd0e199 | 2475 | return NULL_TREE; |
2476 | ||
75a70cf9 | 2477 | for (gsi_next (&i); !gsi_end_p (i); gsi_next (&i)) |
bdd0e199 | 2478 | { |
75a70cf9 | 2479 | stmt = gsi_stmt (i); |
2480 | if (gimple_code (stmt) == GIMPLE_ASM) | |
bdd0e199 | 2481 | return NULL_TREE; |
75a70cf9 | 2482 | if (gimple_code (stmt) != GIMPLE_CALL) |
bdd0e199 | 2483 | continue; |
2484 | ||
75a70cf9 | 2485 | callee = gimple_call_fndecl (stmt); |
c40a6f90 | 2486 | if (!callee |
2487 | || DECL_BUILT_IN_CLASS (callee) != BUILT_IN_NORMAL | |
2488 | /* All regular builtins are ok, just obviously not alloca. */ | |
581bf1c2 | 2489 | || DECL_FUNCTION_CODE (callee) == BUILT_IN_ALLOCA |
2490 | || DECL_FUNCTION_CODE (callee) == BUILT_IN_ALLOCA_WITH_ALIGN) | |
bdd0e199 | 2491 | return NULL_TREE; |
2492 | ||
2493 | if (DECL_FUNCTION_CODE (callee) == BUILT_IN_STACK_RESTORE) | |
6ea999da | 2494 | goto second_stack_restore; |
bdd0e199 | 2495 | } |
2496 | ||
6ea999da | 2497 | if (!gsi_end_p (i)) |
bdd0e199 | 2498 | return NULL_TREE; |
2499 | ||
6ea999da | 2500 | /* Allow one successor of the exit block, or zero successors. */ |
2501 | switch (EDGE_COUNT (bb->succs)) | |
2502 | { | |
2503 | case 0: | |
2504 | break; | |
2505 | case 1: | |
34154e27 | 2506 | if (single_succ_edge (bb)->dest != EXIT_BLOCK_PTR_FOR_FN (cfun)) |
6ea999da | 2507 | return NULL_TREE; |
2508 | break; | |
2509 | default: | |
2510 | return NULL_TREE; | |
2511 | } | |
2512 | second_stack_restore: | |
bdd0e199 | 2513 | |
6ea999da | 2514 | /* If there's exactly one use, then zap the call to __builtin_stack_save. |
2515 | If there are multiple uses, then the last one should remove the call. | |
2516 | In any case, whether the call to __builtin_stack_save can be removed | |
2517 | or not is irrelevant to removing the call to __builtin_stack_restore. */ | |
2518 | if (has_single_use (gimple_call_arg (call, 0))) | |
2519 | { | |
2520 | gimple stack_save = SSA_NAME_DEF_STMT (gimple_call_arg (call, 0)); | |
2521 | if (is_gimple_call (stack_save)) | |
2522 | { | |
2523 | callee = gimple_call_fndecl (stack_save); | |
2524 | if (callee | |
2525 | && DECL_BUILT_IN_CLASS (callee) == BUILT_IN_NORMAL | |
2526 | && DECL_FUNCTION_CODE (callee) == BUILT_IN_STACK_SAVE) | |
2527 | { | |
2528 | gimple_stmt_iterator stack_save_gsi; | |
2529 | tree rhs; | |
bdd0e199 | 2530 | |
6ea999da | 2531 | stack_save_gsi = gsi_for_stmt (stack_save); |
2532 | rhs = build_int_cst (TREE_TYPE (gimple_call_arg (call, 0)), 0); | |
2533 | update_call_from_tree (&stack_save_gsi, rhs); | |
2534 | } | |
2535 | } | |
2536 | } | |
bdd0e199 | 2537 | |
75a70cf9 | 2538 | /* No effect, so the statement will be deleted. */ |
bdd0e199 | 2539 | return integer_zero_node; |
2540 | } | |
75a70cf9 | 2541 | |
8a58ed0a | 2542 | /* If va_list type is a simple pointer and nothing special is needed, |
2543 | optimize __builtin_va_start (&ap, 0) into ap = __builtin_next_arg (0), | |
2544 | __builtin_va_end (&ap) out as NOP and __builtin_va_copy into a simple | |
2545 | pointer assignment. */ | |
2546 | ||
2547 | static tree | |
75a70cf9 | 2548 | optimize_stdarg_builtin (gimple call) |
8a58ed0a | 2549 | { |
5f57a8b1 | 2550 | tree callee, lhs, rhs, cfun_va_list; |
8a58ed0a | 2551 | bool va_list_simple_ptr; |
389dd41b | 2552 | location_t loc = gimple_location (call); |
8a58ed0a | 2553 | |
75a70cf9 | 2554 | if (gimple_code (call) != GIMPLE_CALL) |
8a58ed0a | 2555 | return NULL_TREE; |
2556 | ||
75a70cf9 | 2557 | callee = gimple_call_fndecl (call); |
5f57a8b1 | 2558 | |
2559 | cfun_va_list = targetm.fn_abi_va_list (callee); | |
2560 | va_list_simple_ptr = POINTER_TYPE_P (cfun_va_list) | |
2561 | && (TREE_TYPE (cfun_va_list) == void_type_node | |
2562 | || TREE_TYPE (cfun_va_list) == char_type_node); | |
2563 | ||
8a58ed0a | 2564 | switch (DECL_FUNCTION_CODE (callee)) |
2565 | { | |
2566 | case BUILT_IN_VA_START: | |
2567 | if (!va_list_simple_ptr | |
2568 | || targetm.expand_builtin_va_start != NULL | |
e7ed5dd7 | 2569 | || !builtin_decl_explicit_p (BUILT_IN_NEXT_ARG)) |
8a58ed0a | 2570 | return NULL_TREE; |
2571 | ||
75a70cf9 | 2572 | if (gimple_call_num_args (call) != 2) |
8a58ed0a | 2573 | return NULL_TREE; |
2574 | ||
75a70cf9 | 2575 | lhs = gimple_call_arg (call, 0); |
8a58ed0a | 2576 | if (!POINTER_TYPE_P (TREE_TYPE (lhs)) |
2577 | || TYPE_MAIN_VARIANT (TREE_TYPE (TREE_TYPE (lhs))) | |
5f57a8b1 | 2578 | != TYPE_MAIN_VARIANT (cfun_va_list)) |
8a58ed0a | 2579 | return NULL_TREE; |
48e1416a | 2580 | |
389dd41b | 2581 | lhs = build_fold_indirect_ref_loc (loc, lhs); |
b9a16870 | 2582 | rhs = build_call_expr_loc (loc, builtin_decl_explicit (BUILT_IN_NEXT_ARG), |
75a70cf9 | 2583 | 1, integer_zero_node); |
389dd41b | 2584 | rhs = fold_convert_loc (loc, TREE_TYPE (lhs), rhs); |
8a58ed0a | 2585 | return build2 (MODIFY_EXPR, TREE_TYPE (lhs), lhs, rhs); |
2586 | ||
2587 | case BUILT_IN_VA_COPY: | |
2588 | if (!va_list_simple_ptr) | |
2589 | return NULL_TREE; | |
2590 | ||
75a70cf9 | 2591 | if (gimple_call_num_args (call) != 2) |
8a58ed0a | 2592 | return NULL_TREE; |
2593 | ||
75a70cf9 | 2594 | lhs = gimple_call_arg (call, 0); |
8a58ed0a | 2595 | if (!POINTER_TYPE_P (TREE_TYPE (lhs)) |
2596 | || TYPE_MAIN_VARIANT (TREE_TYPE (TREE_TYPE (lhs))) | |
5f57a8b1 | 2597 | != TYPE_MAIN_VARIANT (cfun_va_list)) |
8a58ed0a | 2598 | return NULL_TREE; |
2599 | ||
389dd41b | 2600 | lhs = build_fold_indirect_ref_loc (loc, lhs); |
75a70cf9 | 2601 | rhs = gimple_call_arg (call, 1); |
8a58ed0a | 2602 | if (TYPE_MAIN_VARIANT (TREE_TYPE (rhs)) |
5f57a8b1 | 2603 | != TYPE_MAIN_VARIANT (cfun_va_list)) |
8a58ed0a | 2604 | return NULL_TREE; |
2605 | ||
389dd41b | 2606 | rhs = fold_convert_loc (loc, TREE_TYPE (lhs), rhs); |
8a58ed0a | 2607 | return build2 (MODIFY_EXPR, TREE_TYPE (lhs), lhs, rhs); |
2608 | ||
2609 | case BUILT_IN_VA_END: | |
75a70cf9 | 2610 | /* No effect, so the statement will be deleted. */ |
8a58ed0a | 2611 | return integer_zero_node; |
2612 | ||
2613 | default: | |
2614 | gcc_unreachable (); | |
2615 | } | |
2616 | } | |
75a70cf9 | 2617 | |
f87df69a | 2618 | /* Attemp to make the block of __builtin_unreachable I unreachable by changing |
2619 | the incoming jumps. Return true if at least one jump was changed. */ | |
2620 | ||
2621 | static bool | |
2622 | optimize_unreachable (gimple_stmt_iterator i) | |
2623 | { | |
2624 | basic_block bb = gsi_bb (i); | |
2625 | gimple_stmt_iterator gsi; | |
2626 | gimple stmt; | |
2627 | edge_iterator ei; | |
2628 | edge e; | |
2629 | bool ret; | |
2630 | ||
f6b540af | 2631 | if (flag_sanitize & SANITIZE_UNREACHABLE) |
2632 | return false; | |
2633 | ||
f87df69a | 2634 | for (gsi = gsi_start_bb (bb); !gsi_end_p (gsi); gsi_next (&gsi)) |
2635 | { | |
2636 | stmt = gsi_stmt (gsi); | |
2637 | ||
2638 | if (is_gimple_debug (stmt)) | |
2639 | continue; | |
2640 | ||
1a91d914 | 2641 | if (glabel *label_stmt = dyn_cast <glabel *> (stmt)) |
f87df69a | 2642 | { |
2643 | /* Verify we do not need to preserve the label. */ | |
1a91d914 | 2644 | if (FORCED_LABEL (gimple_label_label (label_stmt))) |
f87df69a | 2645 | return false; |
2646 | ||
2647 | continue; | |
2648 | } | |
2649 | ||
2650 | /* Only handle the case that __builtin_unreachable is the first statement | |
2651 | in the block. We rely on DCE to remove stmts without side-effects | |
2652 | before __builtin_unreachable. */ | |
2653 | if (gsi_stmt (gsi) != gsi_stmt (i)) | |
2654 | return false; | |
2655 | } | |
2656 | ||
2657 | ret = false; | |
2658 | FOR_EACH_EDGE (e, ei, bb->preds) | |
2659 | { | |
2660 | gsi = gsi_last_bb (e->src); | |
522f73a1 | 2661 | if (gsi_end_p (gsi)) |
2662 | continue; | |
f87df69a | 2663 | |
522f73a1 | 2664 | stmt = gsi_stmt (gsi); |
1a91d914 | 2665 | if (gcond *cond_stmt = dyn_cast <gcond *> (stmt)) |
f87df69a | 2666 | { |
2667 | if (e->flags & EDGE_TRUE_VALUE) | |
1a91d914 | 2668 | gimple_cond_make_false (cond_stmt); |
f87df69a | 2669 | else if (e->flags & EDGE_FALSE_VALUE) |
1a91d914 | 2670 | gimple_cond_make_true (cond_stmt); |
f87df69a | 2671 | else |
2672 | gcc_unreachable (); | |
1a91d914 | 2673 | update_stmt (cond_stmt); |
f87df69a | 2674 | } |
2675 | else | |
2676 | { | |
2677 | /* Todo: handle other cases, f.i. switch statement. */ | |
2678 | continue; | |
2679 | } | |
2680 | ||
2681 | ret = true; | |
2682 | } | |
2683 | ||
2684 | return ret; | |
2685 | } | |
2686 | ||
4ee9c684 | 2687 | /* A simple pass that attempts to fold all builtin functions. This pass |
2688 | is run after we've propagated as many constants as we can. */ | |
2689 | ||
65b0537f | 2690 | namespace { |
2691 | ||
2692 | const pass_data pass_data_fold_builtins = | |
2693 | { | |
2694 | GIMPLE_PASS, /* type */ | |
2695 | "fab", /* name */ | |
2696 | OPTGROUP_NONE, /* optinfo_flags */ | |
65b0537f | 2697 | TV_NONE, /* tv_id */ |
2698 | ( PROP_cfg | PROP_ssa ), /* properties_required */ | |
2699 | 0, /* properties_provided */ | |
2700 | 0, /* properties_destroyed */ | |
2701 | 0, /* todo_flags_start */ | |
8b88439e | 2702 | TODO_update_ssa, /* todo_flags_finish */ |
65b0537f | 2703 | }; |
2704 | ||
2705 | class pass_fold_builtins : public gimple_opt_pass | |
2706 | { | |
2707 | public: | |
2708 | pass_fold_builtins (gcc::context *ctxt) | |
2709 | : gimple_opt_pass (pass_data_fold_builtins, ctxt) | |
2710 | {} | |
2711 | ||
2712 | /* opt_pass methods: */ | |
2713 | opt_pass * clone () { return new pass_fold_builtins (m_ctxt); } | |
2714 | virtual unsigned int execute (function *); | |
2715 | ||
2716 | }; // class pass_fold_builtins | |
2717 | ||
2718 | unsigned int | |
2719 | pass_fold_builtins::execute (function *fun) | |
4ee9c684 | 2720 | { |
b36237eb | 2721 | bool cfg_changed = false; |
4ee9c684 | 2722 | basic_block bb; |
b1b7c0c4 | 2723 | unsigned int todoflags = 0; |
48e1416a | 2724 | |
65b0537f | 2725 | FOR_EACH_BB_FN (bb, fun) |
4ee9c684 | 2726 | { |
75a70cf9 | 2727 | gimple_stmt_iterator i; |
2728 | for (i = gsi_start_bb (bb); !gsi_end_p (i); ) | |
4ee9c684 | 2729 | { |
75a70cf9 | 2730 | gimple stmt, old_stmt; |
40a3eb84 | 2731 | tree callee; |
0a39fd54 | 2732 | enum built_in_function fcode; |
4ee9c684 | 2733 | |
75a70cf9 | 2734 | stmt = gsi_stmt (i); |
2735 | ||
2736 | if (gimple_code (stmt) != GIMPLE_CALL) | |
0a39fd54 | 2737 | { |
896a0c42 | 2738 | /* Remove all *ssaname_N ={v} {CLOBBER}; stmts, |
2739 | after the last GIMPLE DSE they aren't needed and might | |
2740 | unnecessarily keep the SSA_NAMEs live. */ | |
2741 | if (gimple_clobber_p (stmt)) | |
2742 | { | |
2743 | tree lhs = gimple_assign_lhs (stmt); | |
2744 | if (TREE_CODE (lhs) == MEM_REF | |
2745 | && TREE_CODE (TREE_OPERAND (lhs, 0)) == SSA_NAME) | |
2746 | { | |
2747 | unlink_stmt_vdef (stmt); | |
2748 | gsi_remove (&i, true); | |
2749 | release_defs (stmt); | |
2750 | continue; | |
2751 | } | |
2752 | } | |
75a70cf9 | 2753 | gsi_next (&i); |
0a39fd54 | 2754 | continue; |
2755 | } | |
40a3eb84 | 2756 | |
75a70cf9 | 2757 | callee = gimple_call_fndecl (stmt); |
4ee9c684 | 2758 | if (!callee || DECL_BUILT_IN_CLASS (callee) != BUILT_IN_NORMAL) |
0a39fd54 | 2759 | { |
75a70cf9 | 2760 | gsi_next (&i); |
0a39fd54 | 2761 | continue; |
2762 | } | |
5a4b7e1e | 2763 | |
40a3eb84 | 2764 | fcode = DECL_FUNCTION_CODE (callee); |
2765 | if (fold_stmt (&i)) | |
2766 | ; | |
2767 | else | |
2768 | { | |
2769 | tree result = NULL_TREE; | |
2770 | switch (DECL_FUNCTION_CODE (callee)) | |
2771 | { | |
2772 | case BUILT_IN_CONSTANT_P: | |
2773 | /* Resolve __builtin_constant_p. If it hasn't been | |
2774 | folded to integer_one_node by now, it's fairly | |
2775 | certain that the value simply isn't constant. */ | |
2776 | result = integer_zero_node; | |
2777 | break; | |
5a4b7e1e | 2778 | |
40a3eb84 | 2779 | case BUILT_IN_ASSUME_ALIGNED: |
2780 | /* Remove __builtin_assume_aligned. */ | |
2781 | result = gimple_call_arg (stmt, 0); | |
2782 | break; | |
4ee9c684 | 2783 | |
40a3eb84 | 2784 | case BUILT_IN_STACK_RESTORE: |
2785 | result = optimize_stack_restore (i); | |
2786 | if (result) | |
2787 | break; | |
2788 | gsi_next (&i); | |
2789 | continue; | |
fca0886c | 2790 | |
40a3eb84 | 2791 | case BUILT_IN_UNREACHABLE: |
2792 | if (optimize_unreachable (i)) | |
2793 | cfg_changed = true; | |
8a58ed0a | 2794 | break; |
8a58ed0a | 2795 | |
40a3eb84 | 2796 | case BUILT_IN_VA_START: |
2797 | case BUILT_IN_VA_END: | |
2798 | case BUILT_IN_VA_COPY: | |
2799 | /* These shouldn't be folded before pass_stdarg. */ | |
2800 | result = optimize_stdarg_builtin (stmt); | |
2801 | if (result) | |
2802 | break; | |
2803 | /* FALLTHRU */ | |
f87df69a | 2804 | |
40a3eb84 | 2805 | default:; |
2806 | } | |
bdd0e199 | 2807 | |
40a3eb84 | 2808 | if (!result) |
2809 | { | |
2810 | gsi_next (&i); | |
2811 | continue; | |
2812 | } | |
4ee9c684 | 2813 | |
40a3eb84 | 2814 | if (!update_call_from_tree (&i, result)) |
2815 | gimplify_and_update_call_from_tree (&i, result); | |
2816 | } | |
2817 | ||
2818 | todoflags |= TODO_update_address_taken; | |
f87df69a | 2819 | |
4ee9c684 | 2820 | if (dump_file && (dump_flags & TDF_DETAILS)) |
2821 | { | |
2822 | fprintf (dump_file, "Simplified\n "); | |
75a70cf9 | 2823 | print_gimple_stmt (dump_file, stmt, 0, dump_flags); |
4ee9c684 | 2824 | } |
2825 | ||
75a70cf9 | 2826 | old_stmt = stmt; |
75a70cf9 | 2827 | stmt = gsi_stmt (i); |
4c5fd53c | 2828 | update_stmt (stmt); |
de6ed584 | 2829 | |
75a70cf9 | 2830 | if (maybe_clean_or_replace_eh_stmt (old_stmt, stmt) |
2831 | && gimple_purge_dead_eh_edges (bb)) | |
b36237eb | 2832 | cfg_changed = true; |
4ee9c684 | 2833 | |
2834 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
2835 | { | |
2836 | fprintf (dump_file, "to\n "); | |
75a70cf9 | 2837 | print_gimple_stmt (dump_file, stmt, 0, dump_flags); |
4ee9c684 | 2838 | fprintf (dump_file, "\n"); |
2839 | } | |
0a39fd54 | 2840 | |
2841 | /* Retry the same statement if it changed into another | |
2842 | builtin, there might be new opportunities now. */ | |
75a70cf9 | 2843 | if (gimple_code (stmt) != GIMPLE_CALL) |
0a39fd54 | 2844 | { |
75a70cf9 | 2845 | gsi_next (&i); |
0a39fd54 | 2846 | continue; |
2847 | } | |
75a70cf9 | 2848 | callee = gimple_call_fndecl (stmt); |
0a39fd54 | 2849 | if (!callee |
75a70cf9 | 2850 | || DECL_BUILT_IN_CLASS (callee) != BUILT_IN_NORMAL |
0a39fd54 | 2851 | || DECL_FUNCTION_CODE (callee) == fcode) |
75a70cf9 | 2852 | gsi_next (&i); |
4ee9c684 | 2853 | } |
2854 | } | |
48e1416a | 2855 | |
b36237eb | 2856 | /* Delete unreachable blocks. */ |
b1b7c0c4 | 2857 | if (cfg_changed) |
2858 | todoflags |= TODO_cleanup_cfg; | |
48e1416a | 2859 | |
b1b7c0c4 | 2860 | return todoflags; |
4ee9c684 | 2861 | } |
2862 | ||
cbe8bda8 | 2863 | } // anon namespace |
2864 | ||
2865 | gimple_opt_pass * | |
2866 | make_pass_fold_builtins (gcc::context *ctxt) | |
2867 | { | |
2868 | return new pass_fold_builtins (ctxt); | |
2869 | } |