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4ee9c684 | 1 | /* Conditional constant propagation pass for the GNU compiler. |
f1717362 | 2 | Copyright (C) 2000-2016 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" |
7c29e30e | 125 | #include "target.h" |
4ee9c684 | 126 | #include "tree.h" |
9ef16211 | 127 | #include "gimple.h" |
7c29e30e | 128 | #include "tree-pass.h" |
9ef16211 | 129 | #include "ssa.h" |
7c29e30e | 130 | #include "gimple-pretty-print.h" |
b20a8bb4 | 131 | #include "fold-const.h" |
bc61cadb | 132 | #include "gimple-fold.h" |
133 | #include "tree-eh.h" | |
a8783bee | 134 | #include "gimplify.h" |
dcf1a1ec | 135 | #include "gimple-iterator.h" |
073c1fd5 | 136 | #include "tree-cfg.h" |
41511585 | 137 | #include "tree-ssa-propagate.h" |
43fb76c1 | 138 | #include "dbgcnt.h" |
9a65cc0a | 139 | #include "params.h" |
f7715905 | 140 | #include "builtins.h" |
058a1b7a | 141 | #include "tree-chkp.h" |
e2588447 | 142 | #include "cfgloop.h" |
9c1a31e4 | 143 | #include "stor-layout.h" |
144 | #include "optabs-query.h" | |
a54071b2 | 145 | #include "tree-ssa-ccp.h" |
2dc10fae | 146 | |
4ee9c684 | 147 | /* Possible lattice values. */ |
148 | typedef enum | |
149 | { | |
bfa30570 | 150 | UNINITIALIZED, |
4ee9c684 | 151 | UNDEFINED, |
152 | CONSTANT, | |
153 | VARYING | |
88dbf20f | 154 | } ccp_lattice_t; |
4ee9c684 | 155 | |
9908fe4d | 156 | struct ccp_prop_value_t { |
14f101cf | 157 | /* Lattice value. */ |
158 | ccp_lattice_t lattice_val; | |
159 | ||
160 | /* Propagated value. */ | |
161 | tree value; | |
b7e55469 | 162 | |
e913b5cd | 163 | /* Mask that applies to the propagated value during CCP. For X |
164 | with a CONSTANT lattice value X & ~mask == value & ~mask. The | |
165 | zero bits in the mask cover constant values. The ones mean no | |
166 | information. */ | |
5de9d3ed | 167 | widest_int mask; |
14f101cf | 168 | }; |
169 | ||
88dbf20f | 170 | /* Array of propagated constant values. After propagation, |
171 | CONST_VAL[I].VALUE holds the constant value for SSA_NAME(I). If | |
172 | the constant is held in an SSA name representing a memory store | |
4fb5e5ca | 173 | (i.e., a VDEF), CONST_VAL[I].MEM_REF will contain the actual |
174 | memory reference used to store (i.e., the LHS of the assignment | |
175 | doing the store). */ | |
9908fe4d | 176 | static ccp_prop_value_t *const_val; |
285df01b | 177 | static unsigned n_const_val; |
4ee9c684 | 178 | |
9908fe4d | 179 | static void canonicalize_value (ccp_prop_value_t *); |
6688f8ec | 180 | static bool ccp_fold_stmt (gimple_stmt_iterator *); |
27de3d43 | 181 | static void ccp_lattice_meet (ccp_prop_value_t *, ccp_prop_value_t *); |
4af351a8 | 182 | |
88dbf20f | 183 | /* Dump constant propagation value VAL to file OUTF prefixed by PREFIX. */ |
01406fc0 | 184 | |
185 | static void | |
9908fe4d | 186 | dump_lattice_value (FILE *outf, const char *prefix, ccp_prop_value_t val) |
01406fc0 | 187 | { |
41511585 | 188 | switch (val.lattice_val) |
01406fc0 | 189 | { |
88dbf20f | 190 | case UNINITIALIZED: |
191 | fprintf (outf, "%sUNINITIALIZED", prefix); | |
192 | break; | |
41511585 | 193 | case UNDEFINED: |
194 | fprintf (outf, "%sUNDEFINED", prefix); | |
195 | break; | |
196 | case VARYING: | |
197 | fprintf (outf, "%sVARYING", prefix); | |
198 | break; | |
41511585 | 199 | case CONSTANT: |
b7e55469 | 200 | if (TREE_CODE (val.value) != INTEGER_CST |
796b6678 | 201 | || val.mask == 0) |
16ab4e97 | 202 | { |
203 | fprintf (outf, "%sCONSTANT ", prefix); | |
204 | print_generic_expr (outf, val.value, dump_flags); | |
205 | } | |
b7e55469 | 206 | else |
207 | { | |
28e557ef | 208 | widest_int cval = wi::bit_and_not (wi::to_widest (val.value), |
209 | val.mask); | |
e913b5cd | 210 | fprintf (outf, "%sCONSTANT ", prefix); |
211 | print_hex (cval, outf); | |
212 | fprintf (outf, " ("); | |
213 | print_hex (val.mask, outf); | |
214 | fprintf (outf, ")"); | |
b7e55469 | 215 | } |
41511585 | 216 | break; |
217 | default: | |
8c0963c4 | 218 | gcc_unreachable (); |
41511585 | 219 | } |
01406fc0 | 220 | } |
4ee9c684 | 221 | |
4ee9c684 | 222 | |
88dbf20f | 223 | /* Print lattice value VAL to stderr. */ |
224 | ||
9908fe4d | 225 | void debug_lattice_value (ccp_prop_value_t val); |
88dbf20f | 226 | |
4b987fac | 227 | DEBUG_FUNCTION void |
9908fe4d | 228 | debug_lattice_value (ccp_prop_value_t val) |
88dbf20f | 229 | { |
230 | dump_lattice_value (stderr, "", val); | |
231 | fprintf (stderr, "\n"); | |
232 | } | |
4ee9c684 | 233 | |
9a93e2f7 | 234 | /* Extend NONZERO_BITS to a full mask, based on sgn. */ |
9c1be15e | 235 | |
236 | static widest_int | |
9a93e2f7 | 237 | extend_mask (const wide_int &nonzero_bits, signop sgn) |
9c1be15e | 238 | { |
9a93e2f7 | 239 | return widest_int::from (nonzero_bits, sgn); |
9c1be15e | 240 | } |
4ee9c684 | 241 | |
88dbf20f | 242 | /* Compute a default value for variable VAR and store it in the |
243 | CONST_VAL array. The following rules are used to get default | |
244 | values: | |
01406fc0 | 245 | |
88dbf20f | 246 | 1- Global and static variables that are declared constant are |
247 | considered CONSTANT. | |
248 | ||
249 | 2- Any other value is considered UNDEFINED. This is useful when | |
41511585 | 250 | considering PHI nodes. PHI arguments that are undefined do not |
251 | change the constant value of the PHI node, which allows for more | |
88dbf20f | 252 | constants to be propagated. |
4ee9c684 | 253 | |
8883e700 | 254 | 3- Variables defined by statements other than assignments and PHI |
88dbf20f | 255 | nodes are considered VARYING. |
4ee9c684 | 256 | |
8883e700 | 257 | 4- Initial values of variables that are not GIMPLE registers are |
bfa30570 | 258 | considered VARYING. */ |
4ee9c684 | 259 | |
9908fe4d | 260 | static ccp_prop_value_t |
88dbf20f | 261 | get_default_value (tree var) |
262 | { | |
9908fe4d | 263 | ccp_prop_value_t val = { UNINITIALIZED, NULL_TREE, 0 }; |
42acab1c | 264 | gimple *stmt; |
8edeb88b | 265 | |
266 | stmt = SSA_NAME_DEF_STMT (var); | |
267 | ||
268 | if (gimple_nop_p (stmt)) | |
4ee9c684 | 269 | { |
8edeb88b | 270 | /* Variables defined by an empty statement are those used |
271 | before being initialized. If VAR is a local variable, we | |
272 | can assume initially that it is UNDEFINED, otherwise we must | |
273 | consider it VARYING. */ | |
7c782c9b | 274 | if (!virtual_operand_p (var) |
9ae1b28a | 275 | && SSA_NAME_VAR (var) |
7c782c9b | 276 | && TREE_CODE (SSA_NAME_VAR (var)) == VAR_DECL) |
8edeb88b | 277 | val.lattice_val = UNDEFINED; |
278 | else | |
b7e55469 | 279 | { |
280 | val.lattice_val = VARYING; | |
e913b5cd | 281 | val.mask = -1; |
fc08b993 | 282 | if (flag_tree_bit_ccp) |
283 | { | |
9c1be15e | 284 | wide_int nonzero_bits = get_nonzero_bits (var); |
285 | if (nonzero_bits != -1) | |
fc08b993 | 286 | { |
287 | val.lattice_val = CONSTANT; | |
288 | val.value = build_zero_cst (TREE_TYPE (var)); | |
9a93e2f7 | 289 | val.mask = extend_mask (nonzero_bits, TYPE_SIGN (TREE_TYPE (var))); |
fc08b993 | 290 | } |
291 | } | |
b7e55469 | 292 | } |
4ee9c684 | 293 | } |
b45b214a | 294 | else if (is_gimple_assign (stmt)) |
41511585 | 295 | { |
8edeb88b | 296 | tree cst; |
297 | if (gimple_assign_single_p (stmt) | |
298 | && DECL_P (gimple_assign_rhs1 (stmt)) | |
299 | && (cst = get_symbol_constant_value (gimple_assign_rhs1 (stmt)))) | |
88dbf20f | 300 | { |
8edeb88b | 301 | val.lattice_val = CONSTANT; |
302 | val.value = cst; | |
88dbf20f | 303 | } |
304 | else | |
b45b214a | 305 | { |
306 | /* Any other variable defined by an assignment is considered | |
307 | UNDEFINED. */ | |
308 | val.lattice_val = UNDEFINED; | |
309 | } | |
310 | } | |
311 | else if ((is_gimple_call (stmt) | |
312 | && gimple_call_lhs (stmt) != NULL_TREE) | |
313 | || gimple_code (stmt) == GIMPLE_PHI) | |
314 | { | |
315 | /* A variable defined by a call or a PHI node is considered | |
316 | UNDEFINED. */ | |
317 | val.lattice_val = UNDEFINED; | |
8edeb88b | 318 | } |
319 | else | |
320 | { | |
321 | /* Otherwise, VAR will never take on a constant value. */ | |
322 | val.lattice_val = VARYING; | |
e913b5cd | 323 | val.mask = -1; |
41511585 | 324 | } |
4ee9c684 | 325 | |
41511585 | 326 | return val; |
327 | } | |
4ee9c684 | 328 | |
4ee9c684 | 329 | |
bfa30570 | 330 | /* Get the constant value associated with variable VAR. */ |
4ee9c684 | 331 | |
9908fe4d | 332 | static inline ccp_prop_value_t * |
bfa30570 | 333 | get_value (tree var) |
88dbf20f | 334 | { |
9908fe4d | 335 | ccp_prop_value_t *val; |
bfa30570 | 336 | |
285df01b | 337 | if (const_val == NULL |
338 | || SSA_NAME_VERSION (var) >= n_const_val) | |
e004838d | 339 | return NULL; |
340 | ||
341 | val = &const_val[SSA_NAME_VERSION (var)]; | |
bfa30570 | 342 | if (val->lattice_val == UNINITIALIZED) |
4ee9c684 | 343 | *val = get_default_value (var); |
344 | ||
f5faab84 | 345 | canonicalize_value (val); |
4af351a8 | 346 | |
4ee9c684 | 347 | return val; |
348 | } | |
349 | ||
15d138c9 | 350 | /* Return the constant tree value associated with VAR. */ |
351 | ||
352 | static inline tree | |
353 | get_constant_value (tree var) | |
354 | { | |
9908fe4d | 355 | ccp_prop_value_t *val; |
98d92e3c | 356 | if (TREE_CODE (var) != SSA_NAME) |
357 | { | |
358 | if (is_gimple_min_invariant (var)) | |
359 | return var; | |
360 | return NULL_TREE; | |
361 | } | |
362 | val = get_value (var); | |
b7e55469 | 363 | if (val |
364 | && val->lattice_val == CONSTANT | |
365 | && (TREE_CODE (val->value) != INTEGER_CST | |
796b6678 | 366 | || val->mask == 0)) |
15d138c9 | 367 | return val->value; |
368 | return NULL_TREE; | |
369 | } | |
370 | ||
bfa30570 | 371 | /* Sets the value associated with VAR to VARYING. */ |
372 | ||
373 | static inline void | |
374 | set_value_varying (tree var) | |
375 | { | |
9908fe4d | 376 | ccp_prop_value_t *val = &const_val[SSA_NAME_VERSION (var)]; |
bfa30570 | 377 | |
378 | val->lattice_val = VARYING; | |
379 | val->value = NULL_TREE; | |
e913b5cd | 380 | val->mask = -1; |
bfa30570 | 381 | } |
4ee9c684 | 382 | |
0001b944 | 383 | /* For integer constants, make sure to drop TREE_OVERFLOW. */ |
b31eb493 | 384 | |
385 | static void | |
9908fe4d | 386 | canonicalize_value (ccp_prop_value_t *val) |
b31eb493 | 387 | { |
f5faab84 | 388 | if (val->lattice_val != CONSTANT) |
389 | return; | |
390 | ||
391 | if (TREE_OVERFLOW_P (val->value)) | |
392 | val->value = drop_tree_overflow (val->value); | |
b31eb493 | 393 | } |
394 | ||
b7e55469 | 395 | /* Return whether the lattice transition is valid. */ |
396 | ||
397 | static bool | |
9908fe4d | 398 | valid_lattice_transition (ccp_prop_value_t old_val, ccp_prop_value_t new_val) |
b7e55469 | 399 | { |
400 | /* Lattice transitions must always be monotonically increasing in | |
401 | value. */ | |
402 | if (old_val.lattice_val < new_val.lattice_val) | |
403 | return true; | |
404 | ||
405 | if (old_val.lattice_val != new_val.lattice_val) | |
406 | return false; | |
407 | ||
408 | if (!old_val.value && !new_val.value) | |
409 | return true; | |
410 | ||
411 | /* Now both lattice values are CONSTANT. */ | |
412 | ||
fc6cc27b | 413 | /* Allow arbitrary copy changes as we might look through PHI <a_1, ...> |
414 | when only a single copy edge is executable. */ | |
415 | if (TREE_CODE (old_val.value) == SSA_NAME | |
416 | && TREE_CODE (new_val.value) == SSA_NAME) | |
417 | return true; | |
418 | ||
419 | /* Allow transitioning from a constant to a copy. */ | |
420 | if (is_gimple_min_invariant (old_val.value) | |
421 | && TREE_CODE (new_val.value) == SSA_NAME) | |
422 | return true; | |
423 | ||
43c92e0a | 424 | /* Allow transitioning from PHI <&x, not executable> == &x |
425 | to PHI <&x, &y> == common alignment. */ | |
b7e55469 | 426 | if (TREE_CODE (old_val.value) != INTEGER_CST |
427 | && TREE_CODE (new_val.value) == INTEGER_CST) | |
428 | return true; | |
429 | ||
430 | /* Bit-lattices have to agree in the still valid bits. */ | |
431 | if (TREE_CODE (old_val.value) == INTEGER_CST | |
432 | && TREE_CODE (new_val.value) == INTEGER_CST) | |
5de9d3ed | 433 | return (wi::bit_and_not (wi::to_widest (old_val.value), new_val.mask) |
434 | == wi::bit_and_not (wi::to_widest (new_val.value), new_val.mask)); | |
b7e55469 | 435 | |
436 | /* Otherwise constant values have to agree. */ | |
0001b944 | 437 | if (operand_equal_p (old_val.value, new_val.value, 0)) |
438 | return true; | |
439 | ||
440 | /* At least the kinds and types should agree now. */ | |
441 | if (TREE_CODE (old_val.value) != TREE_CODE (new_val.value) | |
442 | || !types_compatible_p (TREE_TYPE (old_val.value), | |
443 | TREE_TYPE (new_val.value))) | |
444 | return false; | |
445 | ||
446 | /* For floats and !HONOR_NANS allow transitions from (partial) NaN | |
447 | to non-NaN. */ | |
448 | tree type = TREE_TYPE (new_val.value); | |
449 | if (SCALAR_FLOAT_TYPE_P (type) | |
93633022 | 450 | && !HONOR_NANS (type)) |
0001b944 | 451 | { |
452 | if (REAL_VALUE_ISNAN (TREE_REAL_CST (old_val.value))) | |
453 | return true; | |
454 | } | |
455 | else if (VECTOR_FLOAT_TYPE_P (type) | |
93633022 | 456 | && !HONOR_NANS (type)) |
0001b944 | 457 | { |
458 | for (unsigned i = 0; i < VECTOR_CST_NELTS (old_val.value); ++i) | |
459 | if (!REAL_VALUE_ISNAN | |
460 | (TREE_REAL_CST (VECTOR_CST_ELT (old_val.value, i))) | |
461 | && !operand_equal_p (VECTOR_CST_ELT (old_val.value, i), | |
462 | VECTOR_CST_ELT (new_val.value, i), 0)) | |
463 | return false; | |
464 | return true; | |
465 | } | |
466 | else if (COMPLEX_FLOAT_TYPE_P (type) | |
93633022 | 467 | && !HONOR_NANS (type)) |
0001b944 | 468 | { |
469 | if (!REAL_VALUE_ISNAN (TREE_REAL_CST (TREE_REALPART (old_val.value))) | |
470 | && !operand_equal_p (TREE_REALPART (old_val.value), | |
471 | TREE_REALPART (new_val.value), 0)) | |
472 | return false; | |
473 | if (!REAL_VALUE_ISNAN (TREE_REAL_CST (TREE_IMAGPART (old_val.value))) | |
474 | && !operand_equal_p (TREE_IMAGPART (old_val.value), | |
475 | TREE_IMAGPART (new_val.value), 0)) | |
476 | return false; | |
477 | return true; | |
478 | } | |
479 | return false; | |
b7e55469 | 480 | } |
481 | ||
88dbf20f | 482 | /* Set the value for variable VAR to NEW_VAL. Return true if the new |
483 | value is different from VAR's previous value. */ | |
4ee9c684 | 484 | |
41511585 | 485 | static bool |
27de3d43 | 486 | set_lattice_value (tree var, ccp_prop_value_t *new_val) |
4ee9c684 | 487 | { |
6d0bf6d6 | 488 | /* We can deal with old UNINITIALIZED values just fine here. */ |
9908fe4d | 489 | ccp_prop_value_t *old_val = &const_val[SSA_NAME_VERSION (var)]; |
88dbf20f | 490 | |
27de3d43 | 491 | canonicalize_value (new_val); |
b31eb493 | 492 | |
b7e55469 | 493 | /* We have to be careful to not go up the bitwise lattice |
27de3d43 | 494 | represented by the mask. Instead of dropping to VARYING |
495 | use the meet operator to retain a conservative value. | |
496 | Missed optimizations like PR65851 makes this necessary. | |
497 | It also ensures we converge to a stable lattice solution. */ | |
498 | if (new_val->lattice_val == CONSTANT | |
b7e55469 | 499 | && old_val->lattice_val == CONSTANT |
27de3d43 | 500 | && TREE_CODE (new_val->value) != SSA_NAME) |
501 | ccp_lattice_meet (new_val, old_val); | |
bfa30570 | 502 | |
27de3d43 | 503 | gcc_checking_assert (valid_lattice_transition (*old_val, *new_val)); |
88dbf20f | 504 | |
b7e55469 | 505 | /* If *OLD_VAL and NEW_VAL are the same, return false to inform the |
506 | caller that this was a non-transition. */ | |
27de3d43 | 507 | if (old_val->lattice_val != new_val->lattice_val |
508 | || (new_val->lattice_val == CONSTANT | |
509 | && (TREE_CODE (new_val->value) != TREE_CODE (old_val->value) | |
510 | || (TREE_CODE (new_val->value) == INTEGER_CST | |
511 | && (new_val->mask != old_val->mask | |
bc1d3d97 | 512 | || (wi::bit_and_not (wi::to_widest (old_val->value), |
27de3d43 | 513 | new_val->mask) |
514 | != wi::bit_and_not (wi::to_widest (new_val->value), | |
515 | new_val->mask)))) | |
516 | || (TREE_CODE (new_val->value) != INTEGER_CST | |
517 | && !operand_equal_p (new_val->value, old_val->value, 0))))) | |
4ee9c684 | 518 | { |
b7e55469 | 519 | /* ??? We would like to delay creation of INTEGER_CSTs from |
520 | partially constants here. */ | |
521 | ||
41511585 | 522 | if (dump_file && (dump_flags & TDF_DETAILS)) |
523 | { | |
27de3d43 | 524 | dump_lattice_value (dump_file, "Lattice value changed to ", *new_val); |
bfa30570 | 525 | fprintf (dump_file, ". Adding SSA edges to worklist.\n"); |
41511585 | 526 | } |
527 | ||
27de3d43 | 528 | *old_val = *new_val; |
88dbf20f | 529 | |
27de3d43 | 530 | gcc_assert (new_val->lattice_val != UNINITIALIZED); |
bfa30570 | 531 | return true; |
4ee9c684 | 532 | } |
41511585 | 533 | |
534 | return false; | |
4ee9c684 | 535 | } |
536 | ||
9908fe4d | 537 | static ccp_prop_value_t get_value_for_expr (tree, bool); |
538 | static ccp_prop_value_t bit_value_binop (enum tree_code, tree, tree, tree); | |
a54071b2 | 539 | void bit_value_binop (enum tree_code, signop, int, widest_int *, widest_int *, |
540 | signop, int, const widest_int &, const widest_int &, | |
541 | signop, int, const widest_int &, const widest_int &); | |
b7e55469 | 542 | |
5de9d3ed | 543 | /* Return a widest_int that can be used for bitwise simplifications |
b7e55469 | 544 | from VAL. */ |
545 | ||
5de9d3ed | 546 | static widest_int |
9908fe4d | 547 | value_to_wide_int (ccp_prop_value_t val) |
b7e55469 | 548 | { |
549 | if (val.value | |
550 | && TREE_CODE (val.value) == INTEGER_CST) | |
5de9d3ed | 551 | return wi::to_widest (val.value); |
e913b5cd | 552 | |
553 | return 0; | |
b7e55469 | 554 | } |
555 | ||
556 | /* Return the value for the address expression EXPR based on alignment | |
557 | information. */ | |
6d0bf6d6 | 558 | |
9908fe4d | 559 | static ccp_prop_value_t |
b7e55469 | 560 | get_value_from_alignment (tree expr) |
561 | { | |
f8abb542 | 562 | tree type = TREE_TYPE (expr); |
9908fe4d | 563 | ccp_prop_value_t val; |
f8abb542 | 564 | unsigned HOST_WIDE_INT bitpos; |
565 | unsigned int align; | |
b7e55469 | 566 | |
567 | gcc_assert (TREE_CODE (expr) == ADDR_EXPR); | |
568 | ||
59da1bcd | 569 | get_pointer_alignment_1 (expr, &align, &bitpos); |
cf8f0e63 | 570 | val.mask = (POINTER_TYPE_P (type) || TYPE_UNSIGNED (type) |
5de9d3ed | 571 | ? wi::mask <widest_int> (TYPE_PRECISION (type), false) |
e913b5cd | 572 | : -1).and_not (align / BITS_PER_UNIT - 1); |
c90d2c17 | 573 | val.lattice_val |
574 | = wi::sext (val.mask, TYPE_PRECISION (type)) == -1 ? VARYING : CONSTANT; | |
f8abb542 | 575 | if (val.lattice_val == CONSTANT) |
796b6678 | 576 | val.value = build_int_cstu (type, bitpos / BITS_PER_UNIT); |
b7e55469 | 577 | else |
f8abb542 | 578 | val.value = NULL_TREE; |
b7e55469 | 579 | |
580 | return val; | |
581 | } | |
582 | ||
583 | /* Return the value for the tree operand EXPR. If FOR_BITS_P is true | |
584 | return constant bits extracted from alignment information for | |
585 | invariant addresses. */ | |
586 | ||
9908fe4d | 587 | static ccp_prop_value_t |
b7e55469 | 588 | get_value_for_expr (tree expr, bool for_bits_p) |
6d0bf6d6 | 589 | { |
9908fe4d | 590 | ccp_prop_value_t val; |
6d0bf6d6 | 591 | |
592 | if (TREE_CODE (expr) == SSA_NAME) | |
b7e55469 | 593 | { |
1941149a | 594 | ccp_prop_value_t *val_ = get_value (expr); |
595 | if (val_) | |
596 | val = *val_; | |
597 | else | |
598 | { | |
599 | val.lattice_val = VARYING; | |
600 | val.value = NULL_TREE; | |
601 | val.mask = -1; | |
602 | } | |
b7e55469 | 603 | if (for_bits_p |
604 | && val.lattice_val == CONSTANT | |
605 | && TREE_CODE (val.value) == ADDR_EXPR) | |
606 | val = get_value_from_alignment (val.value); | |
bc1d3d97 | 607 | /* Fall back to a copy value. */ |
608 | if (!for_bits_p | |
609 | && val.lattice_val == VARYING | |
610 | && !SSA_NAME_OCCURS_IN_ABNORMAL_PHI (expr)) | |
611 | { | |
612 | val.lattice_val = CONSTANT; | |
613 | val.value = expr; | |
614 | val.mask = -1; | |
615 | } | |
b7e55469 | 616 | } |
617 | else if (is_gimple_min_invariant (expr) | |
618 | && (!for_bits_p || TREE_CODE (expr) != ADDR_EXPR)) | |
6d0bf6d6 | 619 | { |
620 | val.lattice_val = CONSTANT; | |
621 | val.value = expr; | |
e913b5cd | 622 | val.mask = 0; |
f5faab84 | 623 | canonicalize_value (&val); |
6d0bf6d6 | 624 | } |
b7e55469 | 625 | else if (TREE_CODE (expr) == ADDR_EXPR) |
626 | val = get_value_from_alignment (expr); | |
6d0bf6d6 | 627 | else |
628 | { | |
629 | val.lattice_val = VARYING; | |
09b2913a | 630 | val.mask = -1; |
6d0bf6d6 | 631 | val.value = NULL_TREE; |
632 | } | |
911a6ef1 | 633 | |
634 | if (val.lattice_val == VARYING | |
635 | && TYPE_UNSIGNED (TREE_TYPE (expr))) | |
636 | val.mask = wi::zext (val.mask, TYPE_PRECISION (TREE_TYPE (expr))); | |
637 | ||
6d0bf6d6 | 638 | return val; |
639 | } | |
640 | ||
88dbf20f | 641 | /* Return the likely CCP lattice value for STMT. |
4ee9c684 | 642 | |
41511585 | 643 | If STMT has no operands, then return CONSTANT. |
4ee9c684 | 644 | |
d61b9af3 | 645 | Else if undefinedness of operands of STMT cause its value to be |
646 | undefined, then return UNDEFINED. | |
4ee9c684 | 647 | |
41511585 | 648 | Else if any operands of STMT are constants, then return CONSTANT. |
4ee9c684 | 649 | |
41511585 | 650 | Else return VARYING. */ |
4ee9c684 | 651 | |
88dbf20f | 652 | static ccp_lattice_t |
42acab1c | 653 | likely_value (gimple *stmt) |
41511585 | 654 | { |
d61b9af3 | 655 | bool has_constant_operand, has_undefined_operand, all_undefined_operands; |
a8a0d56e | 656 | bool has_nsa_operand; |
41511585 | 657 | tree use; |
658 | ssa_op_iter iter; | |
8edeb88b | 659 | unsigned i; |
4ee9c684 | 660 | |
590c3166 | 661 | enum gimple_code code = gimple_code (stmt); |
75a70cf9 | 662 | |
663 | /* This function appears to be called only for assignments, calls, | |
664 | conditionals, and switches, due to the logic in visit_stmt. */ | |
665 | gcc_assert (code == GIMPLE_ASSIGN | |
666 | || code == GIMPLE_CALL | |
667 | || code == GIMPLE_COND | |
668 | || code == GIMPLE_SWITCH); | |
88dbf20f | 669 | |
670 | /* If the statement has volatile operands, it won't fold to a | |
671 | constant value. */ | |
75a70cf9 | 672 | if (gimple_has_volatile_ops (stmt)) |
88dbf20f | 673 | return VARYING; |
674 | ||
75a70cf9 | 675 | /* Arrive here for more complex cases. */ |
bfa30570 | 676 | has_constant_operand = false; |
d61b9af3 | 677 | has_undefined_operand = false; |
678 | all_undefined_operands = true; | |
a8a0d56e | 679 | has_nsa_operand = false; |
8edeb88b | 680 | FOR_EACH_SSA_TREE_OPERAND (use, stmt, iter, SSA_OP_USE) |
41511585 | 681 | { |
9908fe4d | 682 | ccp_prop_value_t *val = get_value (use); |
41511585 | 683 | |
1941149a | 684 | if (val && val->lattice_val == UNDEFINED) |
d61b9af3 | 685 | has_undefined_operand = true; |
686 | else | |
687 | all_undefined_operands = false; | |
88dbf20f | 688 | |
1941149a | 689 | if (val && val->lattice_val == CONSTANT) |
bfa30570 | 690 | has_constant_operand = true; |
a8a0d56e | 691 | |
692 | if (SSA_NAME_IS_DEFAULT_DEF (use) | |
693 | || !prop_simulate_again_p (SSA_NAME_DEF_STMT (use))) | |
694 | has_nsa_operand = true; | |
4ee9c684 | 695 | } |
41511585 | 696 | |
dd277d48 | 697 | /* There may be constants in regular rhs operands. For calls we |
698 | have to ignore lhs, fndecl and static chain, otherwise only | |
699 | the lhs. */ | |
700 | for (i = (is_gimple_call (stmt) ? 2 : 0) + gimple_has_lhs (stmt); | |
8edeb88b | 701 | i < gimple_num_ops (stmt); ++i) |
702 | { | |
703 | tree op = gimple_op (stmt, i); | |
704 | if (!op || TREE_CODE (op) == SSA_NAME) | |
705 | continue; | |
706 | if (is_gimple_min_invariant (op)) | |
707 | has_constant_operand = true; | |
708 | } | |
709 | ||
87c0a9fc | 710 | if (has_constant_operand) |
711 | all_undefined_operands = false; | |
712 | ||
3d483a94 | 713 | if (has_undefined_operand |
714 | && code == GIMPLE_CALL | |
715 | && gimple_call_internal_p (stmt)) | |
716 | switch (gimple_call_internal_fn (stmt)) | |
717 | { | |
718 | /* These 3 builtins use the first argument just as a magic | |
719 | way how to find out a decl uid. */ | |
720 | case IFN_GOMP_SIMD_LANE: | |
721 | case IFN_GOMP_SIMD_VF: | |
722 | case IFN_GOMP_SIMD_LAST_LANE: | |
723 | has_undefined_operand = false; | |
724 | break; | |
725 | default: | |
726 | break; | |
727 | } | |
728 | ||
d61b9af3 | 729 | /* If the operation combines operands like COMPLEX_EXPR make sure to |
730 | not mark the result UNDEFINED if only one part of the result is | |
731 | undefined. */ | |
75a70cf9 | 732 | if (has_undefined_operand && all_undefined_operands) |
d61b9af3 | 733 | return UNDEFINED; |
75a70cf9 | 734 | else if (code == GIMPLE_ASSIGN && has_undefined_operand) |
d61b9af3 | 735 | { |
75a70cf9 | 736 | switch (gimple_assign_rhs_code (stmt)) |
d61b9af3 | 737 | { |
738 | /* Unary operators are handled with all_undefined_operands. */ | |
739 | case PLUS_EXPR: | |
740 | case MINUS_EXPR: | |
d61b9af3 | 741 | case POINTER_PLUS_EXPR: |
d61b9af3 | 742 | /* Not MIN_EXPR, MAX_EXPR. One VARYING operand may be selected. |
743 | Not bitwise operators, one VARYING operand may specify the | |
744 | result completely. Not logical operators for the same reason. | |
05a936a0 | 745 | Not COMPLEX_EXPR as one VARYING operand makes the result partly |
746 | not UNDEFINED. Not *DIV_EXPR, comparisons and shifts because | |
747 | the undefined operand may be promoted. */ | |
d61b9af3 | 748 | return UNDEFINED; |
749 | ||
43c92e0a | 750 | case ADDR_EXPR: |
751 | /* If any part of an address is UNDEFINED, like the index | |
752 | of an ARRAY_EXPR, then treat the result as UNDEFINED. */ | |
753 | return UNDEFINED; | |
754 | ||
d61b9af3 | 755 | default: |
756 | ; | |
757 | } | |
758 | } | |
759 | /* If there was an UNDEFINED operand but the result may be not UNDEFINED | |
c91fedc5 | 760 | fall back to CONSTANT. During iteration UNDEFINED may still drop |
761 | to CONSTANT. */ | |
d61b9af3 | 762 | if (has_undefined_operand) |
c91fedc5 | 763 | return CONSTANT; |
d61b9af3 | 764 | |
8edeb88b | 765 | /* We do not consider virtual operands here -- load from read-only |
766 | memory may have only VARYING virtual operands, but still be | |
a8a0d56e | 767 | constant. Also we can combine the stmt with definitions from |
768 | operands whose definitions are not simulated again. */ | |
bfa30570 | 769 | if (has_constant_operand |
a8a0d56e | 770 | || has_nsa_operand |
8edeb88b | 771 | || gimple_references_memory_p (stmt)) |
88dbf20f | 772 | return CONSTANT; |
773 | ||
bfa30570 | 774 | return VARYING; |
4ee9c684 | 775 | } |
776 | ||
bfa30570 | 777 | /* Returns true if STMT cannot be constant. */ |
778 | ||
779 | static bool | |
42acab1c | 780 | surely_varying_stmt_p (gimple *stmt) |
bfa30570 | 781 | { |
782 | /* If the statement has operands that we cannot handle, it cannot be | |
783 | constant. */ | |
75a70cf9 | 784 | if (gimple_has_volatile_ops (stmt)) |
bfa30570 | 785 | return true; |
786 | ||
f257af64 | 787 | /* If it is a call and does not return a value or is not a |
237e78b1 | 788 | builtin and not an indirect call or a call to function with |
789 | assume_aligned/alloc_align attribute, it is varying. */ | |
75a70cf9 | 790 | if (is_gimple_call (stmt)) |
f257af64 | 791 | { |
237e78b1 | 792 | tree fndecl, fntype = gimple_call_fntype (stmt); |
f257af64 | 793 | if (!gimple_call_lhs (stmt) |
794 | || ((fndecl = gimple_call_fndecl (stmt)) != NULL_TREE | |
237e78b1 | 795 | && !DECL_BUILT_IN (fndecl) |
796 | && !lookup_attribute ("assume_aligned", | |
797 | TYPE_ATTRIBUTES (fntype)) | |
798 | && !lookup_attribute ("alloc_align", | |
799 | TYPE_ATTRIBUTES (fntype)))) | |
f257af64 | 800 | return true; |
801 | } | |
bfa30570 | 802 | |
8edeb88b | 803 | /* Any other store operation is not interesting. */ |
dd277d48 | 804 | else if (gimple_vdef (stmt)) |
8edeb88b | 805 | return true; |
806 | ||
bfa30570 | 807 | /* Anything other than assignments and conditional jumps are not |
808 | interesting for CCP. */ | |
75a70cf9 | 809 | if (gimple_code (stmt) != GIMPLE_ASSIGN |
f257af64 | 810 | && gimple_code (stmt) != GIMPLE_COND |
811 | && gimple_code (stmt) != GIMPLE_SWITCH | |
812 | && gimple_code (stmt) != GIMPLE_CALL) | |
bfa30570 | 813 | return true; |
814 | ||
815 | return false; | |
816 | } | |
4ee9c684 | 817 | |
41511585 | 818 | /* Initialize local data structures for CCP. */ |
4ee9c684 | 819 | |
820 | static void | |
41511585 | 821 | ccp_initialize (void) |
4ee9c684 | 822 | { |
41511585 | 823 | basic_block bb; |
4ee9c684 | 824 | |
285df01b | 825 | n_const_val = num_ssa_names; |
9908fe4d | 826 | const_val = XCNEWVEC (ccp_prop_value_t, n_const_val); |
4ee9c684 | 827 | |
41511585 | 828 | /* Initialize simulation flags for PHI nodes and statements. */ |
fc00614f | 829 | FOR_EACH_BB_FN (bb, cfun) |
4ee9c684 | 830 | { |
75a70cf9 | 831 | gimple_stmt_iterator i; |
4ee9c684 | 832 | |
75a70cf9 | 833 | for (i = gsi_start_bb (bb); !gsi_end_p (i); gsi_next (&i)) |
41511585 | 834 | { |
42acab1c | 835 | gimple *stmt = gsi_stmt (i); |
2193544e | 836 | bool is_varying; |
837 | ||
838 | /* If the statement is a control insn, then we do not | |
839 | want to avoid simulating the statement once. Failure | |
840 | to do so means that those edges will never get added. */ | |
841 | if (stmt_ends_bb_p (stmt)) | |
842 | is_varying = false; | |
843 | else | |
844 | is_varying = surely_varying_stmt_p (stmt); | |
4ee9c684 | 845 | |
bfa30570 | 846 | if (is_varying) |
41511585 | 847 | { |
88dbf20f | 848 | tree def; |
849 | ssa_op_iter iter; | |
850 | ||
851 | /* If the statement will not produce a constant, mark | |
852 | all its outputs VARYING. */ | |
853 | FOR_EACH_SSA_TREE_OPERAND (def, stmt, iter, SSA_OP_ALL_DEFS) | |
8edeb88b | 854 | set_value_varying (def); |
41511585 | 855 | } |
75a70cf9 | 856 | prop_set_simulate_again (stmt, !is_varying); |
41511585 | 857 | } |
4ee9c684 | 858 | } |
859 | ||
75a70cf9 | 860 | /* Now process PHI nodes. We never clear the simulate_again flag on |
861 | phi nodes, since we do not know which edges are executable yet, | |
862 | except for phi nodes for virtual operands when we do not do store ccp. */ | |
fc00614f | 863 | FOR_EACH_BB_FN (bb, cfun) |
4ee9c684 | 864 | { |
1a91d914 | 865 | gphi_iterator i; |
41511585 | 866 | |
75a70cf9 | 867 | for (i = gsi_start_phis (bb); !gsi_end_p (i); gsi_next (&i)) |
868 | { | |
1a91d914 | 869 | gphi *phi = i.phi (); |
75a70cf9 | 870 | |
7c782c9b | 871 | if (virtual_operand_p (gimple_phi_result (phi))) |
75a70cf9 | 872 | prop_set_simulate_again (phi, false); |
bfa30570 | 873 | else |
75a70cf9 | 874 | prop_set_simulate_again (phi, true); |
41511585 | 875 | } |
4ee9c684 | 876 | } |
41511585 | 877 | } |
4ee9c684 | 878 | |
43fb76c1 | 879 | /* Debug count support. Reset the values of ssa names |
880 | VARYING when the total number ssa names analyzed is | |
881 | beyond the debug count specified. */ | |
882 | ||
883 | static void | |
884 | do_dbg_cnt (void) | |
885 | { | |
886 | unsigned i; | |
887 | for (i = 0; i < num_ssa_names; i++) | |
888 | { | |
889 | if (!dbg_cnt (ccp)) | |
890 | { | |
891 | const_val[i].lattice_val = VARYING; | |
e913b5cd | 892 | const_val[i].mask = -1; |
43fb76c1 | 893 | const_val[i].value = NULL_TREE; |
894 | } | |
895 | } | |
896 | } | |
897 | ||
4ee9c684 | 898 | |
88dbf20f | 899 | /* Do final substitution of propagated values, cleanup the flowgraph and |
d0322b7d | 900 | free allocated storage. If NONZERO_P, record nonzero bits. |
4ee9c684 | 901 | |
33a34f1e | 902 | Return TRUE when something was optimized. */ |
903 | ||
904 | static bool | |
a54071b2 | 905 | ccp_finalize (bool nonzero_p) |
4ee9c684 | 906 | { |
43fb76c1 | 907 | bool something_changed; |
153c3b50 | 908 | unsigned i; |
f211616e | 909 | tree name; |
43fb76c1 | 910 | |
911 | do_dbg_cnt (); | |
153c3b50 | 912 | |
913 | /* Derive alignment and misalignment information from partially | |
fc08b993 | 914 | constant pointers in the lattice or nonzero bits from partially |
915 | constant integers. */ | |
f211616e | 916 | FOR_EACH_SSA_NAME (i, name, cfun) |
153c3b50 | 917 | { |
9908fe4d | 918 | ccp_prop_value_t *val; |
153c3b50 | 919 | unsigned int tem, align; |
920 | ||
f211616e | 921 | if (!POINTER_TYPE_P (TREE_TYPE (name)) |
922 | && (!INTEGRAL_TYPE_P (TREE_TYPE (name)) | |
923 | /* Don't record nonzero bits before IPA to avoid | |
924 | using too much memory. */ | |
925 | || !nonzero_p)) | |
153c3b50 | 926 | continue; |
927 | ||
928 | val = get_value (name); | |
929 | if (val->lattice_val != CONSTANT | |
a54071b2 | 930 | || TREE_CODE (val->value) != INTEGER_CST |
931 | || val->mask == 0) | |
153c3b50 | 932 | continue; |
933 | ||
fc08b993 | 934 | if (POINTER_TYPE_P (TREE_TYPE (name))) |
935 | { | |
936 | /* Trailing mask bits specify the alignment, trailing value | |
937 | bits the misalignment. */ | |
aeb682a2 | 938 | tem = val->mask.to_uhwi (); |
ac29ece2 | 939 | align = least_bit_hwi (tem); |
fc08b993 | 940 | if (align > 1) |
941 | set_ptr_info_alignment (get_ptr_info (name), align, | |
f9ae6f95 | 942 | (TREE_INT_CST_LOW (val->value) |
fc08b993 | 943 | & (align - 1))); |
944 | } | |
945 | else | |
946 | { | |
9c1be15e | 947 | unsigned int precision = TYPE_PRECISION (TREE_TYPE (val->value)); |
948 | wide_int nonzero_bits = wide_int::from (val->mask, precision, | |
949 | UNSIGNED) | val->value; | |
fc08b993 | 950 | nonzero_bits &= get_nonzero_bits (name); |
951 | set_nonzero_bits (name, nonzero_bits); | |
952 | } | |
153c3b50 | 953 | } |
954 | ||
88dbf20f | 955 | /* Perform substitutions based on the known constant values. */ |
14f101cf | 956 | something_changed = substitute_and_fold (get_constant_value, |
957 | ccp_fold_stmt, true); | |
4ee9c684 | 958 | |
88dbf20f | 959 | free (const_val); |
e004838d | 960 | const_val = NULL; |
33a34f1e | 961 | return something_changed;; |
4ee9c684 | 962 | } |
963 | ||
964 | ||
88dbf20f | 965 | /* Compute the meet operator between *VAL1 and *VAL2. Store the result |
966 | in VAL1. | |
967 | ||
968 | any M UNDEFINED = any | |
88dbf20f | 969 | any M VARYING = VARYING |
970 | Ci M Cj = Ci if (i == j) | |
971 | Ci M Cj = VARYING if (i != j) | |
bfa30570 | 972 | */ |
4ee9c684 | 973 | |
974 | static void | |
27de3d43 | 975 | ccp_lattice_meet (ccp_prop_value_t *val1, ccp_prop_value_t *val2) |
4ee9c684 | 976 | { |
fc6cc27b | 977 | if (val1->lattice_val == UNDEFINED |
978 | /* For UNDEFINED M SSA we can't always SSA because its definition | |
979 | may not dominate the PHI node. Doing optimistic copy propagation | |
980 | also causes a lot of gcc.dg/uninit-pred*.c FAILs. */ | |
981 | && (val2->lattice_val != CONSTANT | |
982 | || TREE_CODE (val2->value) != SSA_NAME)) | |
4ee9c684 | 983 | { |
88dbf20f | 984 | /* UNDEFINED M any = any */ |
985 | *val1 = *val2; | |
41511585 | 986 | } |
fc6cc27b | 987 | else if (val2->lattice_val == UNDEFINED |
988 | /* See above. */ | |
989 | && (val1->lattice_val != CONSTANT | |
990 | || TREE_CODE (val1->value) != SSA_NAME)) | |
92481a4d | 991 | { |
88dbf20f | 992 | /* any M UNDEFINED = any |
993 | Nothing to do. VAL1 already contains the value we want. */ | |
994 | ; | |
92481a4d | 995 | } |
88dbf20f | 996 | else if (val1->lattice_val == VARYING |
997 | || val2->lattice_val == VARYING) | |
41511585 | 998 | { |
88dbf20f | 999 | /* any M VARYING = VARYING. */ |
1000 | val1->lattice_val = VARYING; | |
e913b5cd | 1001 | val1->mask = -1; |
88dbf20f | 1002 | val1->value = NULL_TREE; |
41511585 | 1003 | } |
b7e55469 | 1004 | else if (val1->lattice_val == CONSTANT |
1005 | && val2->lattice_val == CONSTANT | |
1006 | && TREE_CODE (val1->value) == INTEGER_CST | |
1007 | && TREE_CODE (val2->value) == INTEGER_CST) | |
1008 | { | |
1009 | /* Ci M Cj = Ci if (i == j) | |
1010 | Ci M Cj = VARYING if (i != j) | |
1011 | ||
1012 | For INTEGER_CSTs mask unequal bits. If no equal bits remain, | |
1013 | drop to varying. */ | |
e913b5cd | 1014 | val1->mask = (val1->mask | val2->mask |
5de9d3ed | 1015 | | (wi::to_widest (val1->value) |
1016 | ^ wi::to_widest (val2->value))); | |
c90d2c17 | 1017 | if (wi::sext (val1->mask, TYPE_PRECISION (TREE_TYPE (val1->value))) == -1) |
b7e55469 | 1018 | { |
1019 | val1->lattice_val = VARYING; | |
1020 | val1->value = NULL_TREE; | |
1021 | } | |
1022 | } | |
88dbf20f | 1023 | else if (val1->lattice_val == CONSTANT |
1024 | && val2->lattice_val == CONSTANT | |
27de3d43 | 1025 | && operand_equal_p (val1->value, val2->value, 0)) |
41511585 | 1026 | { |
88dbf20f | 1027 | /* Ci M Cj = Ci if (i == j) |
1028 | Ci M Cj = VARYING if (i != j) | |
1029 | ||
b7e55469 | 1030 | VAL1 already contains the value we want for equivalent values. */ |
1031 | } | |
1032 | else if (val1->lattice_val == CONSTANT | |
1033 | && val2->lattice_val == CONSTANT | |
1034 | && (TREE_CODE (val1->value) == ADDR_EXPR | |
1035 | || TREE_CODE (val2->value) == ADDR_EXPR)) | |
1036 | { | |
1037 | /* When not equal addresses are involved try meeting for | |
1038 | alignment. */ | |
9908fe4d | 1039 | ccp_prop_value_t tem = *val2; |
b7e55469 | 1040 | if (TREE_CODE (val1->value) == ADDR_EXPR) |
1041 | *val1 = get_value_for_expr (val1->value, true); | |
1042 | if (TREE_CODE (val2->value) == ADDR_EXPR) | |
1043 | tem = get_value_for_expr (val2->value, true); | |
27de3d43 | 1044 | ccp_lattice_meet (val1, &tem); |
41511585 | 1045 | } |
1046 | else | |
1047 | { | |
88dbf20f | 1048 | /* Any other combination is VARYING. */ |
1049 | val1->lattice_val = VARYING; | |
e913b5cd | 1050 | val1->mask = -1; |
88dbf20f | 1051 | val1->value = NULL_TREE; |
41511585 | 1052 | } |
4ee9c684 | 1053 | } |
1054 | ||
1055 | ||
41511585 | 1056 | /* Loop through the PHI_NODE's parameters for BLOCK and compare their |
1057 | lattice values to determine PHI_NODE's lattice value. The value of a | |
88dbf20f | 1058 | PHI node is determined calling ccp_lattice_meet with all the arguments |
41511585 | 1059 | of the PHI node that are incoming via executable edges. */ |
4ee9c684 | 1060 | |
41511585 | 1061 | static enum ssa_prop_result |
1a91d914 | 1062 | ccp_visit_phi_node (gphi *phi) |
4ee9c684 | 1063 | { |
75a70cf9 | 1064 | unsigned i; |
bc1d3d97 | 1065 | ccp_prop_value_t new_val; |
4ee9c684 | 1066 | |
41511585 | 1067 | if (dump_file && (dump_flags & TDF_DETAILS)) |
4ee9c684 | 1068 | { |
41511585 | 1069 | fprintf (dump_file, "\nVisiting PHI node: "); |
75a70cf9 | 1070 | print_gimple_stmt (dump_file, phi, 0, dump_flags); |
4ee9c684 | 1071 | } |
4ee9c684 | 1072 | |
bc1d3d97 | 1073 | new_val.lattice_val = UNDEFINED; |
1074 | new_val.value = NULL_TREE; | |
1075 | new_val.mask = 0; | |
4ee9c684 | 1076 | |
bc1d3d97 | 1077 | bool first = true; |
83c60000 | 1078 | bool non_exec_edge = false; |
75a70cf9 | 1079 | for (i = 0; i < gimple_phi_num_args (phi); i++) |
41511585 | 1080 | { |
88dbf20f | 1081 | /* Compute the meet operator over all the PHI arguments flowing |
1082 | through executable edges. */ | |
75a70cf9 | 1083 | edge e = gimple_phi_arg_edge (phi, i); |
4ee9c684 | 1084 | |
41511585 | 1085 | if (dump_file && (dump_flags & TDF_DETAILS)) |
1086 | { | |
1087 | fprintf (dump_file, | |
1088 | "\n Argument #%d (%d -> %d %sexecutable)\n", | |
1089 | i, e->src->index, e->dest->index, | |
1090 | (e->flags & EDGE_EXECUTABLE) ? "" : "not "); | |
1091 | } | |
1092 | ||
1093 | /* If the incoming edge is executable, Compute the meet operator for | |
1094 | the existing value of the PHI node and the current PHI argument. */ | |
1095 | if (e->flags & EDGE_EXECUTABLE) | |
1096 | { | |
75a70cf9 | 1097 | tree arg = gimple_phi_arg (phi, i)->def; |
9908fe4d | 1098 | ccp_prop_value_t arg_val = get_value_for_expr (arg, false); |
4ee9c684 | 1099 | |
bc1d3d97 | 1100 | if (first) |
1101 | { | |
1102 | new_val = arg_val; | |
1103 | first = false; | |
1104 | } | |
1105 | else | |
27de3d43 | 1106 | ccp_lattice_meet (&new_val, &arg_val); |
4ee9c684 | 1107 | |
41511585 | 1108 | if (dump_file && (dump_flags & TDF_DETAILS)) |
1109 | { | |
1110 | fprintf (dump_file, "\t"); | |
88dbf20f | 1111 | print_generic_expr (dump_file, arg, dump_flags); |
1112 | dump_lattice_value (dump_file, "\tValue: ", arg_val); | |
41511585 | 1113 | fprintf (dump_file, "\n"); |
1114 | } | |
4ee9c684 | 1115 | |
41511585 | 1116 | if (new_val.lattice_val == VARYING) |
1117 | break; | |
1118 | } | |
83c60000 | 1119 | else |
1120 | non_exec_edge = true; | |
1121 | } | |
1122 | ||
1123 | /* In case there were non-executable edges and the value is a copy | |
1124 | make sure its definition dominates the PHI node. */ | |
1125 | if (non_exec_edge | |
1126 | && new_val.lattice_val == CONSTANT | |
1127 | && TREE_CODE (new_val.value) == SSA_NAME | |
1128 | && ! SSA_NAME_IS_DEFAULT_DEF (new_val.value) | |
1129 | && ! dominated_by_p (CDI_DOMINATORS, gimple_bb (phi), | |
1130 | gimple_bb (SSA_NAME_DEF_STMT (new_val.value)))) | |
1131 | { | |
1132 | new_val.lattice_val = VARYING; | |
1133 | new_val.value = NULL_TREE; | |
1134 | new_val.mask = -1; | |
41511585 | 1135 | } |
4ee9c684 | 1136 | |
1137 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
41511585 | 1138 | { |
1139 | dump_lattice_value (dump_file, "\n PHI node value: ", new_val); | |
1140 | fprintf (dump_file, "\n\n"); | |
1141 | } | |
1142 | ||
bfa30570 | 1143 | /* Make the transition to the new value. */ |
27de3d43 | 1144 | if (set_lattice_value (gimple_phi_result (phi), &new_val)) |
41511585 | 1145 | { |
1146 | if (new_val.lattice_val == VARYING) | |
1147 | return SSA_PROP_VARYING; | |
1148 | else | |
1149 | return SSA_PROP_INTERESTING; | |
1150 | } | |
1151 | else | |
1152 | return SSA_PROP_NOT_INTERESTING; | |
4ee9c684 | 1153 | } |
1154 | ||
15d138c9 | 1155 | /* Return the constant value for OP or OP otherwise. */ |
00f4f705 | 1156 | |
1157 | static tree | |
15d138c9 | 1158 | valueize_op (tree op) |
00f4f705 | 1159 | { |
00f4f705 | 1160 | if (TREE_CODE (op) == SSA_NAME) |
1161 | { | |
15d138c9 | 1162 | tree tem = get_constant_value (op); |
1163 | if (tem) | |
1164 | return tem; | |
00f4f705 | 1165 | } |
1166 | return op; | |
1167 | } | |
1168 | ||
4e1b3545 | 1169 | /* Return the constant value for OP, but signal to not follow SSA |
1170 | edges if the definition may be simulated again. */ | |
1171 | ||
1172 | static tree | |
1173 | valueize_op_1 (tree op) | |
1174 | { | |
1175 | if (TREE_CODE (op) == SSA_NAME) | |
1176 | { | |
4e1b3545 | 1177 | /* If the definition may be simulated again we cannot follow |
1178 | this SSA edge as the SSA propagator does not necessarily | |
1179 | re-visit the use. */ | |
42acab1c | 1180 | gimple *def_stmt = SSA_NAME_DEF_STMT (op); |
2160d5ba | 1181 | if (!gimple_nop_p (def_stmt) |
1182 | && prop_simulate_again_p (def_stmt)) | |
4e1b3545 | 1183 | return NULL_TREE; |
bc8fa068 | 1184 | tree tem = get_constant_value (op); |
1185 | if (tem) | |
1186 | return tem; | |
4e1b3545 | 1187 | } |
1188 | return op; | |
1189 | } | |
1190 | ||
41511585 | 1191 | /* CCP specific front-end to the non-destructive constant folding |
1192 | routines. | |
4ee9c684 | 1193 | |
1194 | Attempt to simplify the RHS of STMT knowing that one or more | |
1195 | operands are constants. | |
1196 | ||
1197 | If simplification is possible, return the simplified RHS, | |
75a70cf9 | 1198 | otherwise return the original RHS or NULL_TREE. */ |
4ee9c684 | 1199 | |
1200 | static tree | |
42acab1c | 1201 | ccp_fold (gimple *stmt) |
4ee9c684 | 1202 | { |
389dd41b | 1203 | location_t loc = gimple_location (stmt); |
75a70cf9 | 1204 | switch (gimple_code (stmt)) |
88dbf20f | 1205 | { |
75a70cf9 | 1206 | case GIMPLE_COND: |
1207 | { | |
1208 | /* Handle comparison operators that can appear in GIMPLE form. */ | |
15d138c9 | 1209 | tree op0 = valueize_op (gimple_cond_lhs (stmt)); |
1210 | tree op1 = valueize_op (gimple_cond_rhs (stmt)); | |
75a70cf9 | 1211 | enum tree_code code = gimple_cond_code (stmt); |
389dd41b | 1212 | return fold_binary_loc (loc, code, boolean_type_node, op0, op1); |
75a70cf9 | 1213 | } |
4ee9c684 | 1214 | |
75a70cf9 | 1215 | case GIMPLE_SWITCH: |
1216 | { | |
15d138c9 | 1217 | /* Return the constant switch index. */ |
1a91d914 | 1218 | return valueize_op (gimple_switch_index (as_a <gswitch *> (stmt))); |
75a70cf9 | 1219 | } |
912f109f | 1220 | |
1d0b727d | 1221 | case GIMPLE_ASSIGN: |
1222 | case GIMPLE_CALL: | |
4e1b3545 | 1223 | return gimple_fold_stmt_to_constant_1 (stmt, |
1224 | valueize_op, valueize_op_1); | |
04236c3a | 1225 | |
8782adcf | 1226 | default: |
1d0b727d | 1227 | gcc_unreachable (); |
8782adcf | 1228 | } |
8782adcf | 1229 | } |
75a70cf9 | 1230 | |
b7e55469 | 1231 | /* Apply the operation CODE in type TYPE to the value, mask pair |
1232 | RVAL and RMASK representing a value of type RTYPE and set | |
1233 | the value, mask pair *VAL and *MASK to the result. */ | |
1234 | ||
a54071b2 | 1235 | void |
1236 | bit_value_unop (enum tree_code code, signop type_sgn, int type_precision, | |
1237 | widest_int *val, widest_int *mask, | |
1238 | signop rtype_sgn, int rtype_precision, | |
1239 | const widest_int &rval, const widest_int &rmask) | |
b7e55469 | 1240 | { |
1241 | switch (code) | |
1242 | { | |
1243 | case BIT_NOT_EXPR: | |
1244 | *mask = rmask; | |
cf8f0e63 | 1245 | *val = ~rval; |
b7e55469 | 1246 | break; |
1247 | ||
1248 | case NEGATE_EXPR: | |
1249 | { | |
5de9d3ed | 1250 | widest_int temv, temm; |
b7e55469 | 1251 | /* Return ~rval + 1. */ |
a54071b2 | 1252 | bit_value_unop (BIT_NOT_EXPR, type_sgn, type_precision, &temv, &temm, |
1253 | type_sgn, type_precision, rval, rmask); | |
1254 | bit_value_binop (PLUS_EXPR, type_sgn, type_precision, val, mask, | |
1255 | type_sgn, type_precision, temv, temm, | |
1256 | type_sgn, type_precision, 1, 0); | |
b7e55469 | 1257 | break; |
1258 | } | |
1259 | ||
1260 | CASE_CONVERT: | |
1261 | { | |
b7e55469 | 1262 | /* First extend mask and value according to the original type. */ |
a54071b2 | 1263 | *mask = wi::ext (rmask, rtype_precision, rtype_sgn); |
1264 | *val = wi::ext (rval, rtype_precision, rtype_sgn); | |
b7e55469 | 1265 | |
1266 | /* Then extend mask and value according to the target type. */ | |
a54071b2 | 1267 | *mask = wi::ext (*mask, type_precision, type_sgn); |
1268 | *val = wi::ext (*val, type_precision, type_sgn); | |
b7e55469 | 1269 | break; |
1270 | } | |
1271 | ||
1272 | default: | |
e913b5cd | 1273 | *mask = -1; |
b7e55469 | 1274 | break; |
1275 | } | |
1276 | } | |
1277 | ||
1278 | /* Apply the operation CODE in type TYPE to the value, mask pairs | |
1279 | R1VAL, R1MASK and R2VAL, R2MASK representing a values of type R1TYPE | |
1280 | and R2TYPE and set the value, mask pair *VAL and *MASK to the result. */ | |
1281 | ||
a54071b2 | 1282 | void |
1283 | bit_value_binop (enum tree_code code, signop sgn, int width, | |
1284 | widest_int *val, widest_int *mask, | |
1285 | signop r1type_sgn, int r1type_precision, | |
1286 | const widest_int &r1val, const widest_int &r1mask, | |
1287 | signop r2type_sgn, int r2type_precision, | |
1288 | const widest_int &r2val, const widest_int &r2mask) | |
b7e55469 | 1289 | { |
10c3fe8d | 1290 | bool swap_p = false; |
e913b5cd | 1291 | |
1292 | /* Assume we'll get a constant result. Use an initial non varying | |
1293 | value, we fall back to varying in the end if necessary. */ | |
1294 | *mask = -1; | |
1295 | ||
b7e55469 | 1296 | switch (code) |
1297 | { | |
1298 | case BIT_AND_EXPR: | |
1299 | /* The mask is constant where there is a known not | |
1300 | set bit, (m1 | m2) & ((v1 | m1) & (v2 | m2)) */ | |
cf8f0e63 | 1301 | *mask = (r1mask | r2mask) & (r1val | r1mask) & (r2val | r2mask); |
1302 | *val = r1val & r2val; | |
b7e55469 | 1303 | break; |
1304 | ||
1305 | case BIT_IOR_EXPR: | |
1306 | /* The mask is constant where there is a known | |
1307 | set bit, (m1 | m2) & ~((v1 & ~m1) | (v2 & ~m2)). */ | |
cf8f0e63 | 1308 | *mask = (r1mask | r2mask) |
1309 | .and_not (r1val.and_not (r1mask) | r2val.and_not (r2mask)); | |
1310 | *val = r1val | r2val; | |
b7e55469 | 1311 | break; |
1312 | ||
1313 | case BIT_XOR_EXPR: | |
1314 | /* m1 | m2 */ | |
cf8f0e63 | 1315 | *mask = r1mask | r2mask; |
1316 | *val = r1val ^ r2val; | |
b7e55469 | 1317 | break; |
1318 | ||
1319 | case LROTATE_EXPR: | |
1320 | case RROTATE_EXPR: | |
796b6678 | 1321 | if (r2mask == 0) |
b7e55469 | 1322 | { |
28e557ef | 1323 | widest_int shift = r2val; |
796b6678 | 1324 | if (shift == 0) |
e913b5cd | 1325 | { |
1326 | *mask = r1mask; | |
1327 | *val = r1val; | |
1328 | } | |
ddb1be65 | 1329 | else |
e913b5cd | 1330 | { |
796b6678 | 1331 | if (wi::neg_p (shift)) |
e913b5cd | 1332 | { |
1333 | shift = -shift; | |
1334 | if (code == RROTATE_EXPR) | |
1335 | code = LROTATE_EXPR; | |
1336 | else | |
1337 | code = RROTATE_EXPR; | |
1338 | } | |
1339 | if (code == RROTATE_EXPR) | |
1340 | { | |
796b6678 | 1341 | *mask = wi::rrotate (r1mask, shift, width); |
1342 | *val = wi::rrotate (r1val, shift, width); | |
e913b5cd | 1343 | } |
1344 | else | |
1345 | { | |
796b6678 | 1346 | *mask = wi::lrotate (r1mask, shift, width); |
1347 | *val = wi::lrotate (r1val, shift, width); | |
e913b5cd | 1348 | } |
1349 | } | |
b7e55469 | 1350 | } |
1351 | break; | |
1352 | ||
1353 | case LSHIFT_EXPR: | |
1354 | case RSHIFT_EXPR: | |
1355 | /* ??? We can handle partially known shift counts if we know | |
1356 | its sign. That way we can tell that (x << (y | 8)) & 255 | |
1357 | is zero. */ | |
796b6678 | 1358 | if (r2mask == 0) |
b7e55469 | 1359 | { |
28e557ef | 1360 | widest_int shift = r2val; |
796b6678 | 1361 | if (shift == 0) |
b7e55469 | 1362 | { |
1363 | *mask = r1mask; | |
1364 | *val = r1val; | |
1365 | } | |
ddb1be65 | 1366 | else |
e913b5cd | 1367 | { |
796b6678 | 1368 | if (wi::neg_p (shift)) |
e913b5cd | 1369 | { |
1370 | shift = -shift; | |
1371 | if (code == RSHIFT_EXPR) | |
1372 | code = LSHIFT_EXPR; | |
1373 | else | |
1374 | code = RSHIFT_EXPR; | |
1375 | } | |
1376 | if (code == RSHIFT_EXPR) | |
1377 | { | |
45639915 | 1378 | *mask = wi::rshift (wi::ext (r1mask, width, sgn), shift, sgn); |
1379 | *val = wi::rshift (wi::ext (r1val, width, sgn), shift, sgn); | |
e913b5cd | 1380 | } |
1381 | else | |
1382 | { | |
9fdc1ed4 | 1383 | *mask = wi::ext (r1mask << shift, width, sgn); |
1384 | *val = wi::ext (r1val << shift, width, sgn); | |
e913b5cd | 1385 | } |
1386 | } | |
b7e55469 | 1387 | } |
1388 | break; | |
1389 | ||
1390 | case PLUS_EXPR: | |
1391 | case POINTER_PLUS_EXPR: | |
1392 | { | |
b7e55469 | 1393 | /* Do the addition with unknown bits set to zero, to give carry-ins of |
1394 | zero wherever possible. */ | |
ab2c1de8 | 1395 | widest_int lo = r1val.and_not (r1mask) + r2val.and_not (r2mask); |
796b6678 | 1396 | lo = wi::ext (lo, width, sgn); |
b7e55469 | 1397 | /* Do the addition with unknown bits set to one, to give carry-ins of |
1398 | one wherever possible. */ | |
ab2c1de8 | 1399 | widest_int hi = (r1val | r1mask) + (r2val | r2mask); |
796b6678 | 1400 | hi = wi::ext (hi, width, sgn); |
b7e55469 | 1401 | /* Each bit in the result is known if (a) the corresponding bits in |
1402 | both inputs are known, and (b) the carry-in to that bit position | |
1403 | is known. We can check condition (b) by seeing if we got the same | |
1404 | result with minimised carries as with maximised carries. */ | |
cf8f0e63 | 1405 | *mask = r1mask | r2mask | (lo ^ hi); |
796b6678 | 1406 | *mask = wi::ext (*mask, width, sgn); |
b7e55469 | 1407 | /* It shouldn't matter whether we choose lo or hi here. */ |
1408 | *val = lo; | |
1409 | break; | |
1410 | } | |
1411 | ||
1412 | case MINUS_EXPR: | |
1413 | { | |
5de9d3ed | 1414 | widest_int temv, temm; |
a54071b2 | 1415 | bit_value_unop (NEGATE_EXPR, r2type_sgn, r2type_precision, &temv, &temm, |
1416 | r2type_sgn, r2type_precision, r2val, r2mask); | |
1417 | bit_value_binop (PLUS_EXPR, sgn, width, val, mask, | |
1418 | r1type_sgn, r1type_precision, r1val, r1mask, | |
1419 | r2type_sgn, r2type_precision, temv, temm); | |
b7e55469 | 1420 | break; |
1421 | } | |
1422 | ||
1423 | case MULT_EXPR: | |
1424 | { | |
1425 | /* Just track trailing zeros in both operands and transfer | |
1426 | them to the other. */ | |
796b6678 | 1427 | int r1tz = wi::ctz (r1val | r1mask); |
1428 | int r2tz = wi::ctz (r2val | r2mask); | |
e913b5cd | 1429 | if (r1tz + r2tz >= width) |
b7e55469 | 1430 | { |
e913b5cd | 1431 | *mask = 0; |
1432 | *val = 0; | |
b7e55469 | 1433 | } |
1434 | else if (r1tz + r2tz > 0) | |
1435 | { | |
5de9d3ed | 1436 | *mask = wi::ext (wi::mask <widest_int> (r1tz + r2tz, true), |
796b6678 | 1437 | width, sgn); |
e913b5cd | 1438 | *val = 0; |
b7e55469 | 1439 | } |
1440 | break; | |
1441 | } | |
1442 | ||
1443 | case EQ_EXPR: | |
1444 | case NE_EXPR: | |
1445 | { | |
5de9d3ed | 1446 | widest_int m = r1mask | r2mask; |
cf8f0e63 | 1447 | if (r1val.and_not (m) != r2val.and_not (m)) |
b7e55469 | 1448 | { |
e913b5cd | 1449 | *mask = 0; |
1450 | *val = ((code == EQ_EXPR) ? 0 : 1); | |
b7e55469 | 1451 | } |
1452 | else | |
1453 | { | |
1454 | /* We know the result of a comparison is always one or zero. */ | |
e913b5cd | 1455 | *mask = 1; |
1456 | *val = 0; | |
b7e55469 | 1457 | } |
1458 | break; | |
1459 | } | |
1460 | ||
1461 | case GE_EXPR: | |
1462 | case GT_EXPR: | |
10c3fe8d | 1463 | swap_p = true; |
1464 | code = swap_tree_comparison (code); | |
1465 | /* Fall through. */ | |
b7e55469 | 1466 | case LT_EXPR: |
1467 | case LE_EXPR: | |
1468 | { | |
1469 | int minmax, maxmin; | |
e913b5cd | 1470 | |
10c3fe8d | 1471 | const widest_int &o1val = swap_p ? r2val : r1val; |
1472 | const widest_int &o1mask = swap_p ? r2mask : r1mask; | |
1473 | const widest_int &o2val = swap_p ? r1val : r2val; | |
1474 | const widest_int &o2mask = swap_p ? r1mask : r2mask; | |
1475 | ||
b7e55469 | 1476 | /* If the most significant bits are not known we know nothing. */ |
796b6678 | 1477 | if (wi::neg_p (o1mask) || wi::neg_p (o2mask)) |
b7e55469 | 1478 | break; |
1479 | ||
90c0f5b7 | 1480 | /* For comparisons the signedness is in the comparison operands. */ |
a54071b2 | 1481 | sgn = r1type_sgn; |
90c0f5b7 | 1482 | |
b7e55469 | 1483 | /* If we know the most significant bits we know the values |
1484 | value ranges by means of treating varying bits as zero | |
1485 | or one. Do a cross comparison of the max/min pairs. */ | |
796b6678 | 1486 | maxmin = wi::cmp (o1val | o1mask, o2val.and_not (o2mask), sgn); |
1487 | minmax = wi::cmp (o1val.and_not (o1mask), o2val | o2mask, sgn); | |
e913b5cd | 1488 | if (maxmin < 0) /* o1 is less than o2. */ |
b7e55469 | 1489 | { |
e913b5cd | 1490 | *mask = 0; |
1491 | *val = 1; | |
b7e55469 | 1492 | } |
e913b5cd | 1493 | else if (minmax > 0) /* o1 is not less or equal to o2. */ |
b7e55469 | 1494 | { |
e913b5cd | 1495 | *mask = 0; |
1496 | *val = 0; | |
b7e55469 | 1497 | } |
e913b5cd | 1498 | else if (maxmin == minmax) /* o1 and o2 are equal. */ |
b7e55469 | 1499 | { |
1500 | /* This probably should never happen as we'd have | |
1501 | folded the thing during fully constant value folding. */ | |
e913b5cd | 1502 | *mask = 0; |
1503 | *val = (code == LE_EXPR ? 1 : 0); | |
b7e55469 | 1504 | } |
1505 | else | |
1506 | { | |
1507 | /* We know the result of a comparison is always one or zero. */ | |
e913b5cd | 1508 | *mask = 1; |
1509 | *val = 0; | |
b7e55469 | 1510 | } |
1511 | break; | |
1512 | } | |
1513 | ||
1514 | default:; | |
1515 | } | |
1516 | } | |
1517 | ||
1518 | /* Return the propagation value when applying the operation CODE to | |
1519 | the value RHS yielding type TYPE. */ | |
1520 | ||
9908fe4d | 1521 | static ccp_prop_value_t |
b7e55469 | 1522 | bit_value_unop (enum tree_code code, tree type, tree rhs) |
1523 | { | |
9908fe4d | 1524 | ccp_prop_value_t rval = get_value_for_expr (rhs, true); |
5de9d3ed | 1525 | widest_int value, mask; |
9908fe4d | 1526 | ccp_prop_value_t val; |
c91fedc5 | 1527 | |
1528 | if (rval.lattice_val == UNDEFINED) | |
1529 | return rval; | |
1530 | ||
b7e55469 | 1531 | gcc_assert ((rval.lattice_val == CONSTANT |
1532 | && TREE_CODE (rval.value) == INTEGER_CST) | |
c90d2c17 | 1533 | || wi::sext (rval.mask, TYPE_PRECISION (TREE_TYPE (rhs))) == -1); |
a54071b2 | 1534 | bit_value_unop (code, TYPE_SIGN (type), TYPE_PRECISION (type), &value, &mask, |
1535 | TYPE_SIGN (TREE_TYPE (rhs)), TYPE_PRECISION (TREE_TYPE (rhs)), | |
1536 | value_to_wide_int (rval), rval.mask); | |
c90d2c17 | 1537 | if (wi::sext (mask, TYPE_PRECISION (type)) != -1) |
b7e55469 | 1538 | { |
1539 | val.lattice_val = CONSTANT; | |
1540 | val.mask = mask; | |
1541 | /* ??? Delay building trees here. */ | |
e913b5cd | 1542 | val.value = wide_int_to_tree (type, value); |
b7e55469 | 1543 | } |
1544 | else | |
1545 | { | |
1546 | val.lattice_val = VARYING; | |
1547 | val.value = NULL_TREE; | |
e913b5cd | 1548 | val.mask = -1; |
b7e55469 | 1549 | } |
1550 | return val; | |
1551 | } | |
1552 | ||
1553 | /* Return the propagation value when applying the operation CODE to | |
1554 | the values RHS1 and RHS2 yielding type TYPE. */ | |
1555 | ||
9908fe4d | 1556 | static ccp_prop_value_t |
b7e55469 | 1557 | bit_value_binop (enum tree_code code, tree type, tree rhs1, tree rhs2) |
1558 | { | |
9908fe4d | 1559 | ccp_prop_value_t r1val = get_value_for_expr (rhs1, true); |
1560 | ccp_prop_value_t r2val = get_value_for_expr (rhs2, true); | |
5de9d3ed | 1561 | widest_int value, mask; |
9908fe4d | 1562 | ccp_prop_value_t val; |
c91fedc5 | 1563 | |
1564 | if (r1val.lattice_val == UNDEFINED | |
1565 | || r2val.lattice_val == UNDEFINED) | |
1566 | { | |
1567 | val.lattice_val = VARYING; | |
1568 | val.value = NULL_TREE; | |
e913b5cd | 1569 | val.mask = -1; |
c91fedc5 | 1570 | return val; |
1571 | } | |
1572 | ||
b7e55469 | 1573 | gcc_assert ((r1val.lattice_val == CONSTANT |
1574 | && TREE_CODE (r1val.value) == INTEGER_CST) | |
c90d2c17 | 1575 | || wi::sext (r1val.mask, |
1576 | TYPE_PRECISION (TREE_TYPE (rhs1))) == -1); | |
b7e55469 | 1577 | gcc_assert ((r2val.lattice_val == CONSTANT |
1578 | && TREE_CODE (r2val.value) == INTEGER_CST) | |
c90d2c17 | 1579 | || wi::sext (r2val.mask, |
1580 | TYPE_PRECISION (TREE_TYPE (rhs2))) == -1); | |
a54071b2 | 1581 | bit_value_binop (code, TYPE_SIGN (type), TYPE_PRECISION (type), &value, &mask, |
1582 | TYPE_SIGN (TREE_TYPE (rhs1)), TYPE_PRECISION (TREE_TYPE (rhs1)), | |
1583 | value_to_wide_int (r1val), r1val.mask, | |
1584 | TYPE_SIGN (TREE_TYPE (rhs2)), TYPE_PRECISION (TREE_TYPE (rhs2)), | |
1585 | value_to_wide_int (r2val), r2val.mask); | |
1586 | ||
c90d2c17 | 1587 | if (wi::sext (mask, TYPE_PRECISION (type)) != -1) |
b7e55469 | 1588 | { |
1589 | val.lattice_val = CONSTANT; | |
1590 | val.mask = mask; | |
1591 | /* ??? Delay building trees here. */ | |
e913b5cd | 1592 | val.value = wide_int_to_tree (type, value); |
b7e55469 | 1593 | } |
1594 | else | |
1595 | { | |
1596 | val.lattice_val = VARYING; | |
1597 | val.value = NULL_TREE; | |
e913b5cd | 1598 | val.mask = -1; |
b7e55469 | 1599 | } |
1600 | return val; | |
1601 | } | |
1602 | ||
237e78b1 | 1603 | /* Return the propagation value for __builtin_assume_aligned |
1604 | and functions with assume_aligned or alloc_aligned attribute. | |
1605 | For __builtin_assume_aligned, ATTR is NULL_TREE, | |
1606 | for assume_aligned attribute ATTR is non-NULL and ALLOC_ALIGNED | |
1607 | is false, for alloc_aligned attribute ATTR is non-NULL and | |
1608 | ALLOC_ALIGNED is true. */ | |
fca0886c | 1609 | |
9908fe4d | 1610 | static ccp_prop_value_t |
42acab1c | 1611 | bit_value_assume_aligned (gimple *stmt, tree attr, ccp_prop_value_t ptrval, |
237e78b1 | 1612 | bool alloc_aligned) |
fca0886c | 1613 | { |
237e78b1 | 1614 | tree align, misalign = NULL_TREE, type; |
fca0886c | 1615 | unsigned HOST_WIDE_INT aligni, misaligni = 0; |
9908fe4d | 1616 | ccp_prop_value_t alignval; |
5de9d3ed | 1617 | widest_int value, mask; |
9908fe4d | 1618 | ccp_prop_value_t val; |
e913b5cd | 1619 | |
237e78b1 | 1620 | if (attr == NULL_TREE) |
1621 | { | |
1622 | tree ptr = gimple_call_arg (stmt, 0); | |
1623 | type = TREE_TYPE (ptr); | |
1624 | ptrval = get_value_for_expr (ptr, true); | |
1625 | } | |
1626 | else | |
1627 | { | |
1628 | tree lhs = gimple_call_lhs (stmt); | |
1629 | type = TREE_TYPE (lhs); | |
1630 | } | |
1631 | ||
fca0886c | 1632 | if (ptrval.lattice_val == UNDEFINED) |
1633 | return ptrval; | |
1634 | gcc_assert ((ptrval.lattice_val == CONSTANT | |
1635 | && TREE_CODE (ptrval.value) == INTEGER_CST) | |
c90d2c17 | 1636 | || wi::sext (ptrval.mask, TYPE_PRECISION (type)) == -1); |
237e78b1 | 1637 | if (attr == NULL_TREE) |
fca0886c | 1638 | { |
237e78b1 | 1639 | /* Get aligni and misaligni from __builtin_assume_aligned. */ |
1640 | align = gimple_call_arg (stmt, 1); | |
1641 | if (!tree_fits_uhwi_p (align)) | |
fca0886c | 1642 | return ptrval; |
237e78b1 | 1643 | aligni = tree_to_uhwi (align); |
1644 | if (gimple_call_num_args (stmt) > 2) | |
1645 | { | |
1646 | misalign = gimple_call_arg (stmt, 2); | |
1647 | if (!tree_fits_uhwi_p (misalign)) | |
1648 | return ptrval; | |
1649 | misaligni = tree_to_uhwi (misalign); | |
1650 | } | |
1651 | } | |
1652 | else | |
fca0886c | 1653 | { |
237e78b1 | 1654 | /* Get aligni and misaligni from assume_aligned or |
1655 | alloc_align attributes. */ | |
1656 | if (TREE_VALUE (attr) == NULL_TREE) | |
fca0886c | 1657 | return ptrval; |
237e78b1 | 1658 | attr = TREE_VALUE (attr); |
1659 | align = TREE_VALUE (attr); | |
1660 | if (!tree_fits_uhwi_p (align)) | |
fca0886c | 1661 | return ptrval; |
237e78b1 | 1662 | aligni = tree_to_uhwi (align); |
1663 | if (alloc_aligned) | |
1664 | { | |
1665 | if (aligni == 0 || aligni > gimple_call_num_args (stmt)) | |
1666 | return ptrval; | |
1667 | align = gimple_call_arg (stmt, aligni - 1); | |
1668 | if (!tree_fits_uhwi_p (align)) | |
1669 | return ptrval; | |
1670 | aligni = tree_to_uhwi (align); | |
1671 | } | |
1672 | else if (TREE_CHAIN (attr) && TREE_VALUE (TREE_CHAIN (attr))) | |
1673 | { | |
1674 | misalign = TREE_VALUE (TREE_CHAIN (attr)); | |
1675 | if (!tree_fits_uhwi_p (misalign)) | |
1676 | return ptrval; | |
1677 | misaligni = tree_to_uhwi (misalign); | |
1678 | } | |
fca0886c | 1679 | } |
237e78b1 | 1680 | if (aligni <= 1 || (aligni & (aligni - 1)) != 0 || misaligni >= aligni) |
1681 | return ptrval; | |
1682 | ||
fca0886c | 1683 | align = build_int_cst_type (type, -aligni); |
1684 | alignval = get_value_for_expr (align, true); | |
a54071b2 | 1685 | bit_value_binop (BIT_AND_EXPR, TYPE_SIGN (type), TYPE_PRECISION (type), &value, &mask, |
1686 | TYPE_SIGN (type), TYPE_PRECISION (type), value_to_wide_int (ptrval), ptrval.mask, | |
1687 | TYPE_SIGN (type), TYPE_PRECISION (type), value_to_wide_int (alignval), alignval.mask); | |
1688 | ||
c90d2c17 | 1689 | if (wi::sext (mask, TYPE_PRECISION (type)) != -1) |
fca0886c | 1690 | { |
1691 | val.lattice_val = CONSTANT; | |
1692 | val.mask = mask; | |
e913b5cd | 1693 | gcc_assert ((mask.to_uhwi () & (aligni - 1)) == 0); |
1694 | gcc_assert ((value.to_uhwi () & (aligni - 1)) == 0); | |
1695 | value |= misaligni; | |
fca0886c | 1696 | /* ??? Delay building trees here. */ |
e913b5cd | 1697 | val.value = wide_int_to_tree (type, value); |
fca0886c | 1698 | } |
1699 | else | |
1700 | { | |
1701 | val.lattice_val = VARYING; | |
1702 | val.value = NULL_TREE; | |
e913b5cd | 1703 | val.mask = -1; |
fca0886c | 1704 | } |
1705 | return val; | |
1706 | } | |
1707 | ||
75a70cf9 | 1708 | /* Evaluate statement STMT. |
1709 | Valid only for assignments, calls, conditionals, and switches. */ | |
4ee9c684 | 1710 | |
9908fe4d | 1711 | static ccp_prop_value_t |
42acab1c | 1712 | evaluate_stmt (gimple *stmt) |
4ee9c684 | 1713 | { |
9908fe4d | 1714 | ccp_prop_value_t val; |
4f61cce6 | 1715 | tree simplified = NULL_TREE; |
88dbf20f | 1716 | ccp_lattice_t likelyvalue = likely_value (stmt); |
b7e55469 | 1717 | bool is_constant = false; |
581bf1c2 | 1718 | unsigned int align; |
88dbf20f | 1719 | |
b7e55469 | 1720 | if (dump_file && (dump_flags & TDF_DETAILS)) |
1721 | { | |
1722 | fprintf (dump_file, "which is likely "); | |
1723 | switch (likelyvalue) | |
1724 | { | |
1725 | case CONSTANT: | |
1726 | fprintf (dump_file, "CONSTANT"); | |
1727 | break; | |
1728 | case UNDEFINED: | |
1729 | fprintf (dump_file, "UNDEFINED"); | |
1730 | break; | |
1731 | case VARYING: | |
1732 | fprintf (dump_file, "VARYING"); | |
1733 | break; | |
1734 | default:; | |
1735 | } | |
1736 | fprintf (dump_file, "\n"); | |
1737 | } | |
add6ee5e | 1738 | |
4ee9c684 | 1739 | /* If the statement is likely to have a CONSTANT result, then try |
1740 | to fold the statement to determine the constant value. */ | |
75a70cf9 | 1741 | /* FIXME. This is the only place that we call ccp_fold. |
1742 | Since likely_value never returns CONSTANT for calls, we will | |
1743 | not attempt to fold them, including builtins that may profit. */ | |
4ee9c684 | 1744 | if (likelyvalue == CONSTANT) |
b7e55469 | 1745 | { |
1746 | fold_defer_overflow_warnings (); | |
1747 | simplified = ccp_fold (stmt); | |
27de3d43 | 1748 | if (simplified && TREE_CODE (simplified) == SSA_NAME) |
1749 | { | |
1941149a | 1750 | ccp_prop_value_t *val = get_value (simplified); |
1751 | if (val && val->lattice_val != VARYING) | |
27de3d43 | 1752 | { |
1753 | fold_undefer_overflow_warnings (true, stmt, 0); | |
1941149a | 1754 | return *val; |
27de3d43 | 1755 | } |
1756 | } | |
b7e55469 | 1757 | is_constant = simplified && is_gimple_min_invariant (simplified); |
1758 | fold_undefer_overflow_warnings (is_constant, stmt, 0); | |
1759 | if (is_constant) | |
1760 | { | |
1761 | /* The statement produced a constant value. */ | |
1762 | val.lattice_val = CONSTANT; | |
1763 | val.value = simplified; | |
e913b5cd | 1764 | val.mask = 0; |
27de3d43 | 1765 | return val; |
b7e55469 | 1766 | } |
1767 | } | |
4ee9c684 | 1768 | /* If the statement is likely to have a VARYING result, then do not |
1769 | bother folding the statement. */ | |
04236c3a | 1770 | else if (likelyvalue == VARYING) |
75a70cf9 | 1771 | { |
590c3166 | 1772 | enum gimple_code code = gimple_code (stmt); |
75a70cf9 | 1773 | if (code == GIMPLE_ASSIGN) |
1774 | { | |
1775 | enum tree_code subcode = gimple_assign_rhs_code (stmt); | |
48e1416a | 1776 | |
75a70cf9 | 1777 | /* Other cases cannot satisfy is_gimple_min_invariant |
1778 | without folding. */ | |
1779 | if (get_gimple_rhs_class (subcode) == GIMPLE_SINGLE_RHS) | |
1780 | simplified = gimple_assign_rhs1 (stmt); | |
1781 | } | |
1782 | else if (code == GIMPLE_SWITCH) | |
1a91d914 | 1783 | simplified = gimple_switch_index (as_a <gswitch *> (stmt)); |
75a70cf9 | 1784 | else |
a65c4d64 | 1785 | /* These cannot satisfy is_gimple_min_invariant without folding. */ |
1786 | gcc_assert (code == GIMPLE_CALL || code == GIMPLE_COND); | |
b7e55469 | 1787 | is_constant = simplified && is_gimple_min_invariant (simplified); |
1788 | if (is_constant) | |
1789 | { | |
1790 | /* The statement produced a constant value. */ | |
1791 | val.lattice_val = CONSTANT; | |
1792 | val.value = simplified; | |
e913b5cd | 1793 | val.mask = 0; |
b7e55469 | 1794 | } |
75a70cf9 | 1795 | } |
4c9206f2 | 1796 | /* If the statement result is likely UNDEFINED, make it so. */ |
1797 | else if (likelyvalue == UNDEFINED) | |
1798 | { | |
1799 | val.lattice_val = UNDEFINED; | |
1800 | val.value = NULL_TREE; | |
1801 | val.mask = 0; | |
1802 | return val; | |
1803 | } | |
4ee9c684 | 1804 | |
b7e55469 | 1805 | /* Resort to simplification for bitwise tracking. */ |
1806 | if (flag_tree_bit_ccp | |
db48deb0 | 1807 | && (likelyvalue == CONSTANT || is_gimple_call (stmt) |
1808 | || (gimple_assign_single_p (stmt) | |
1809 | && gimple_assign_rhs_code (stmt) == ADDR_EXPR)) | |
b7e55469 | 1810 | && !is_constant) |
912f109f | 1811 | { |
b7e55469 | 1812 | enum gimple_code code = gimple_code (stmt); |
1813 | val.lattice_val = VARYING; | |
1814 | val.value = NULL_TREE; | |
e913b5cd | 1815 | val.mask = -1; |
b7e55469 | 1816 | if (code == GIMPLE_ASSIGN) |
912f109f | 1817 | { |
b7e55469 | 1818 | enum tree_code subcode = gimple_assign_rhs_code (stmt); |
1819 | tree rhs1 = gimple_assign_rhs1 (stmt); | |
c0a4b664 | 1820 | tree lhs = gimple_assign_lhs (stmt); |
1821 | if ((INTEGRAL_TYPE_P (TREE_TYPE (lhs)) | |
1822 | || POINTER_TYPE_P (TREE_TYPE (lhs))) | |
1823 | && (INTEGRAL_TYPE_P (TREE_TYPE (rhs1)) | |
1824 | || POINTER_TYPE_P (TREE_TYPE (rhs1)))) | |
1825 | switch (get_gimple_rhs_class (subcode)) | |
1826 | { | |
1827 | case GIMPLE_SINGLE_RHS: | |
1828 | val = get_value_for_expr (rhs1, true); | |
1829 | break; | |
1830 | ||
1831 | case GIMPLE_UNARY_RHS: | |
1832 | val = bit_value_unop (subcode, TREE_TYPE (lhs), rhs1); | |
1833 | break; | |
1834 | ||
1835 | case GIMPLE_BINARY_RHS: | |
1836 | val = bit_value_binop (subcode, TREE_TYPE (lhs), rhs1, | |
1837 | gimple_assign_rhs2 (stmt)); | |
1838 | break; | |
1839 | ||
1840 | default:; | |
1841 | } | |
912f109f | 1842 | } |
b7e55469 | 1843 | else if (code == GIMPLE_COND) |
1844 | { | |
1845 | enum tree_code code = gimple_cond_code (stmt); | |
1846 | tree rhs1 = gimple_cond_lhs (stmt); | |
1847 | tree rhs2 = gimple_cond_rhs (stmt); | |
1848 | if (INTEGRAL_TYPE_P (TREE_TYPE (rhs1)) | |
1849 | || POINTER_TYPE_P (TREE_TYPE (rhs1))) | |
1850 | val = bit_value_binop (code, TREE_TYPE (rhs1), rhs1, rhs2); | |
1851 | } | |
0b4f0116 | 1852 | else if (gimple_call_builtin_p (stmt, BUILT_IN_NORMAL)) |
153c3b50 | 1853 | { |
0b4f0116 | 1854 | tree fndecl = gimple_call_fndecl (stmt); |
153c3b50 | 1855 | switch (DECL_FUNCTION_CODE (fndecl)) |
1856 | { | |
1857 | case BUILT_IN_MALLOC: | |
1858 | case BUILT_IN_REALLOC: | |
1859 | case BUILT_IN_CALLOC: | |
939514e9 | 1860 | case BUILT_IN_STRDUP: |
1861 | case BUILT_IN_STRNDUP: | |
153c3b50 | 1862 | val.lattice_val = CONSTANT; |
1863 | val.value = build_int_cst (TREE_TYPE (gimple_get_lhs (stmt)), 0); | |
796b6678 | 1864 | val.mask = ~((HOST_WIDE_INT) MALLOC_ABI_ALIGNMENT |
1865 | / BITS_PER_UNIT - 1); | |
153c3b50 | 1866 | break; |
1867 | ||
1868 | case BUILT_IN_ALLOCA: | |
581bf1c2 | 1869 | case BUILT_IN_ALLOCA_WITH_ALIGN: |
1870 | align = (DECL_FUNCTION_CODE (fndecl) == BUILT_IN_ALLOCA_WITH_ALIGN | |
f9ae6f95 | 1871 | ? TREE_INT_CST_LOW (gimple_call_arg (stmt, 1)) |
581bf1c2 | 1872 | : BIGGEST_ALIGNMENT); |
153c3b50 | 1873 | val.lattice_val = CONSTANT; |
1874 | val.value = build_int_cst (TREE_TYPE (gimple_get_lhs (stmt)), 0); | |
796b6678 | 1875 | val.mask = ~((HOST_WIDE_INT) align / BITS_PER_UNIT - 1); |
153c3b50 | 1876 | break; |
1877 | ||
939514e9 | 1878 | /* These builtins return their first argument, unmodified. */ |
1879 | case BUILT_IN_MEMCPY: | |
1880 | case BUILT_IN_MEMMOVE: | |
1881 | case BUILT_IN_MEMSET: | |
1882 | case BUILT_IN_STRCPY: | |
1883 | case BUILT_IN_STRNCPY: | |
1884 | case BUILT_IN_MEMCPY_CHK: | |
1885 | case BUILT_IN_MEMMOVE_CHK: | |
1886 | case BUILT_IN_MEMSET_CHK: | |
1887 | case BUILT_IN_STRCPY_CHK: | |
1888 | case BUILT_IN_STRNCPY_CHK: | |
1889 | val = get_value_for_expr (gimple_call_arg (stmt, 0), true); | |
1890 | break; | |
1891 | ||
fca0886c | 1892 | case BUILT_IN_ASSUME_ALIGNED: |
237e78b1 | 1893 | val = bit_value_assume_aligned (stmt, NULL_TREE, val, false); |
fca0886c | 1894 | break; |
1895 | ||
060fc206 | 1896 | case BUILT_IN_ALIGNED_ALLOC: |
1897 | { | |
1898 | tree align = get_constant_value (gimple_call_arg (stmt, 0)); | |
1899 | if (align | |
1900 | && tree_fits_uhwi_p (align)) | |
1901 | { | |
1902 | unsigned HOST_WIDE_INT aligni = tree_to_uhwi (align); | |
1903 | if (aligni > 1 | |
1904 | /* align must be power-of-two */ | |
1905 | && (aligni & (aligni - 1)) == 0) | |
1906 | { | |
1907 | val.lattice_val = CONSTANT; | |
1908 | val.value = build_int_cst (ptr_type_node, 0); | |
cd89b631 | 1909 | val.mask = -aligni; |
060fc206 | 1910 | } |
1911 | } | |
1912 | break; | |
1913 | } | |
1914 | ||
153c3b50 | 1915 | default:; |
1916 | } | |
1917 | } | |
237e78b1 | 1918 | if (is_gimple_call (stmt) && gimple_call_lhs (stmt)) |
1919 | { | |
1920 | tree fntype = gimple_call_fntype (stmt); | |
1921 | if (fntype) | |
1922 | { | |
1923 | tree attrs = lookup_attribute ("assume_aligned", | |
1924 | TYPE_ATTRIBUTES (fntype)); | |
1925 | if (attrs) | |
1926 | val = bit_value_assume_aligned (stmt, attrs, val, false); | |
1927 | attrs = lookup_attribute ("alloc_align", | |
1928 | TYPE_ATTRIBUTES (fntype)); | |
1929 | if (attrs) | |
1930 | val = bit_value_assume_aligned (stmt, attrs, val, true); | |
1931 | } | |
1932 | } | |
b7e55469 | 1933 | is_constant = (val.lattice_val == CONSTANT); |
912f109f | 1934 | } |
1935 | ||
fc08b993 | 1936 | if (flag_tree_bit_ccp |
1937 | && ((is_constant && TREE_CODE (val.value) == INTEGER_CST) | |
4c9206f2 | 1938 | || !is_constant) |
fc08b993 | 1939 | && gimple_get_lhs (stmt) |
1940 | && TREE_CODE (gimple_get_lhs (stmt)) == SSA_NAME) | |
1941 | { | |
1942 | tree lhs = gimple_get_lhs (stmt); | |
9c1be15e | 1943 | wide_int nonzero_bits = get_nonzero_bits (lhs); |
1944 | if (nonzero_bits != -1) | |
fc08b993 | 1945 | { |
1946 | if (!is_constant) | |
1947 | { | |
1948 | val.lattice_val = CONSTANT; | |
1949 | val.value = build_zero_cst (TREE_TYPE (lhs)); | |
9a93e2f7 | 1950 | val.mask = extend_mask (nonzero_bits, TYPE_SIGN (TREE_TYPE (lhs))); |
fc08b993 | 1951 | is_constant = true; |
1952 | } | |
1953 | else | |
1954 | { | |
9c1be15e | 1955 | if (wi::bit_and_not (val.value, nonzero_bits) != 0) |
aeb682a2 | 1956 | val.value = wide_int_to_tree (TREE_TYPE (lhs), |
9c1be15e | 1957 | nonzero_bits & val.value); |
aeb682a2 | 1958 | if (nonzero_bits == 0) |
1959 | val.mask = 0; | |
fc08b993 | 1960 | else |
9a93e2f7 | 1961 | val.mask = val.mask & extend_mask (nonzero_bits, |
1962 | TYPE_SIGN (TREE_TYPE (lhs))); | |
fc08b993 | 1963 | } |
1964 | } | |
1965 | } | |
1966 | ||
4c9206f2 | 1967 | /* The statement produced a nonconstant value. */ |
b7e55469 | 1968 | if (!is_constant) |
4ee9c684 | 1969 | { |
fc6cc27b | 1970 | /* The statement produced a copy. */ |
1971 | if (simplified && TREE_CODE (simplified) == SSA_NAME | |
1972 | && !SSA_NAME_OCCURS_IN_ABNORMAL_PHI (simplified)) | |
1973 | { | |
1974 | val.lattice_val = CONSTANT; | |
1975 | val.value = simplified; | |
1976 | val.mask = -1; | |
1977 | } | |
1978 | /* The statement is VARYING. */ | |
1979 | else | |
1980 | { | |
1981 | val.lattice_val = VARYING; | |
1982 | val.value = NULL_TREE; | |
1983 | val.mask = -1; | |
1984 | } | |
4ee9c684 | 1985 | } |
41511585 | 1986 | |
1987 | return val; | |
4ee9c684 | 1988 | } |
1989 | ||
42acab1c | 1990 | typedef hash_table<nofree_ptr_hash<gimple> > gimple_htab; |
2b15d2ba | 1991 | |
582a80ed | 1992 | /* Given a BUILT_IN_STACK_SAVE value SAVED_VAL, insert a clobber of VAR before |
1993 | each matching BUILT_IN_STACK_RESTORE. Mark visited phis in VISITED. */ | |
1994 | ||
1995 | static void | |
2b15d2ba | 1996 | insert_clobber_before_stack_restore (tree saved_val, tree var, |
c1f445d2 | 1997 | gimple_htab **visited) |
582a80ed | 1998 | { |
42acab1c | 1999 | gimple *stmt; |
1a91d914 | 2000 | gassign *clobber_stmt; |
582a80ed | 2001 | tree clobber; |
2002 | imm_use_iterator iter; | |
2003 | gimple_stmt_iterator i; | |
42acab1c | 2004 | gimple **slot; |
582a80ed | 2005 | |
2006 | FOR_EACH_IMM_USE_STMT (stmt, iter, saved_val) | |
2007 | if (gimple_call_builtin_p (stmt, BUILT_IN_STACK_RESTORE)) | |
2008 | { | |
f1f41a6c | 2009 | clobber = build_constructor (TREE_TYPE (var), |
2010 | NULL); | |
582a80ed | 2011 | TREE_THIS_VOLATILE (clobber) = 1; |
2012 | clobber_stmt = gimple_build_assign (var, clobber); | |
2013 | ||
2014 | i = gsi_for_stmt (stmt); | |
2015 | gsi_insert_before (&i, clobber_stmt, GSI_SAME_STMT); | |
2016 | } | |
2017 | else if (gimple_code (stmt) == GIMPLE_PHI) | |
2018 | { | |
c1f445d2 | 2019 | if (!*visited) |
2020 | *visited = new gimple_htab (10); | |
582a80ed | 2021 | |
c1f445d2 | 2022 | slot = (*visited)->find_slot (stmt, INSERT); |
582a80ed | 2023 | if (*slot != NULL) |
2024 | continue; | |
2025 | ||
2026 | *slot = stmt; | |
2027 | insert_clobber_before_stack_restore (gimple_phi_result (stmt), var, | |
2028 | visited); | |
2029 | } | |
42eed683 | 2030 | else if (gimple_assign_ssa_name_copy_p (stmt)) |
2031 | insert_clobber_before_stack_restore (gimple_assign_lhs (stmt), var, | |
2032 | visited); | |
058a1b7a | 2033 | else if (chkp_gimple_call_builtin_p (stmt, BUILT_IN_CHKP_BNDRET)) |
2034 | continue; | |
582a80ed | 2035 | else |
2036 | gcc_assert (is_gimple_debug (stmt)); | |
2037 | } | |
2038 | ||
2039 | /* Advance the iterator to the previous non-debug gimple statement in the same | |
2040 | or dominating basic block. */ | |
2041 | ||
2042 | static inline void | |
2043 | gsi_prev_dom_bb_nondebug (gimple_stmt_iterator *i) | |
2044 | { | |
2045 | basic_block dom; | |
2046 | ||
2047 | gsi_prev_nondebug (i); | |
2048 | while (gsi_end_p (*i)) | |
2049 | { | |
2050 | dom = get_immediate_dominator (CDI_DOMINATORS, i->bb); | |
34154e27 | 2051 | if (dom == NULL || dom == ENTRY_BLOCK_PTR_FOR_FN (cfun)) |
582a80ed | 2052 | return; |
2053 | ||
2054 | *i = gsi_last_bb (dom); | |
2055 | } | |
2056 | } | |
2057 | ||
2058 | /* Find a BUILT_IN_STACK_SAVE dominating gsi_stmt (I), and insert | |
1543f720 | 2059 | a clobber of VAR before each matching BUILT_IN_STACK_RESTORE. |
2060 | ||
2061 | It is possible that BUILT_IN_STACK_SAVE cannot be find in a dominator when a | |
2062 | previous pass (such as DOM) duplicated it along multiple paths to a BB. In | |
2063 | that case the function gives up without inserting the clobbers. */ | |
582a80ed | 2064 | |
2065 | static void | |
2066 | insert_clobbers_for_var (gimple_stmt_iterator i, tree var) | |
2067 | { | |
42acab1c | 2068 | gimple *stmt; |
582a80ed | 2069 | tree saved_val; |
c1f445d2 | 2070 | gimple_htab *visited = NULL; |
582a80ed | 2071 | |
1543f720 | 2072 | for (; !gsi_end_p (i); gsi_prev_dom_bb_nondebug (&i)) |
582a80ed | 2073 | { |
2074 | stmt = gsi_stmt (i); | |
2075 | ||
2076 | if (!gimple_call_builtin_p (stmt, BUILT_IN_STACK_SAVE)) | |
2077 | continue; | |
582a80ed | 2078 | |
2079 | saved_val = gimple_call_lhs (stmt); | |
2080 | if (saved_val == NULL_TREE) | |
2081 | continue; | |
2082 | ||
2083 | insert_clobber_before_stack_restore (saved_val, var, &visited); | |
2084 | break; | |
2085 | } | |
2086 | ||
c1f445d2 | 2087 | delete visited; |
582a80ed | 2088 | } |
2089 | ||
581bf1c2 | 2090 | /* Detects a __builtin_alloca_with_align with constant size argument. Declares |
2091 | fixed-size array and returns the address, if found, otherwise returns | |
2092 | NULL_TREE. */ | |
9a65cc0a | 2093 | |
2094 | static tree | |
42acab1c | 2095 | fold_builtin_alloca_with_align (gimple *stmt) |
9a65cc0a | 2096 | { |
2097 | unsigned HOST_WIDE_INT size, threshold, n_elem; | |
2098 | tree lhs, arg, block, var, elem_type, array_type; | |
9a65cc0a | 2099 | |
2100 | /* Get lhs. */ | |
2101 | lhs = gimple_call_lhs (stmt); | |
2102 | if (lhs == NULL_TREE) | |
2103 | return NULL_TREE; | |
2104 | ||
2105 | /* Detect constant argument. */ | |
2106 | arg = get_constant_value (gimple_call_arg (stmt, 0)); | |
6e93d308 | 2107 | if (arg == NULL_TREE |
2108 | || TREE_CODE (arg) != INTEGER_CST | |
e913b5cd | 2109 | || !tree_fits_uhwi_p (arg)) |
9a65cc0a | 2110 | return NULL_TREE; |
6e93d308 | 2111 | |
8c53c46c | 2112 | size = tree_to_uhwi (arg); |
9a65cc0a | 2113 | |
581bf1c2 | 2114 | /* Heuristic: don't fold large allocas. */ |
9a65cc0a | 2115 | threshold = (unsigned HOST_WIDE_INT)PARAM_VALUE (PARAM_LARGE_STACK_FRAME); |
581bf1c2 | 2116 | /* In case the alloca is located at function entry, it has the same lifetime |
2117 | as a declared array, so we allow a larger size. */ | |
9a65cc0a | 2118 | block = gimple_block (stmt); |
2119 | if (!(cfun->after_inlining | |
14df71e4 | 2120 | && block |
9a65cc0a | 2121 | && TREE_CODE (BLOCK_SUPERCONTEXT (block)) == FUNCTION_DECL)) |
2122 | threshold /= 10; | |
2123 | if (size > threshold) | |
2124 | return NULL_TREE; | |
2125 | ||
2126 | /* Declare array. */ | |
2127 | elem_type = build_nonstandard_integer_type (BITS_PER_UNIT, 1); | |
2128 | n_elem = size * 8 / BITS_PER_UNIT; | |
9a65cc0a | 2129 | array_type = build_array_type_nelts (elem_type, n_elem); |
f9e245b2 | 2130 | var = create_tmp_var (array_type); |
5d4b30ea | 2131 | SET_DECL_ALIGN (var, TREE_INT_CST_LOW (gimple_call_arg (stmt, 1))); |
3d4a0a4b | 2132 | { |
2133 | struct ptr_info_def *pi = SSA_NAME_PTR_INFO (lhs); | |
2134 | if (pi != NULL && !pi->pt.anything) | |
2135 | { | |
2136 | bool singleton_p; | |
2137 | unsigned uid; | |
5b48910f | 2138 | singleton_p = pt_solution_singleton_or_null_p (&pi->pt, &uid); |
3d4a0a4b | 2139 | gcc_assert (singleton_p); |
2140 | SET_DECL_PT_UID (var, uid); | |
2141 | } | |
2142 | } | |
9a65cc0a | 2143 | |
2144 | /* Fold alloca to the address of the array. */ | |
2145 | return fold_convert (TREE_TYPE (lhs), build_fold_addr_expr (var)); | |
2146 | } | |
2147 | ||
6688f8ec | 2148 | /* Fold the stmt at *GSI with CCP specific information that propagating |
2149 | and regular folding does not catch. */ | |
2150 | ||
2151 | static bool | |
2152 | ccp_fold_stmt (gimple_stmt_iterator *gsi) | |
2153 | { | |
42acab1c | 2154 | gimple *stmt = gsi_stmt (*gsi); |
6688f8ec | 2155 | |
94144e68 | 2156 | switch (gimple_code (stmt)) |
2157 | { | |
2158 | case GIMPLE_COND: | |
2159 | { | |
1a91d914 | 2160 | gcond *cond_stmt = as_a <gcond *> (stmt); |
9908fe4d | 2161 | ccp_prop_value_t val; |
94144e68 | 2162 | /* Statement evaluation will handle type mismatches in constants |
2163 | more gracefully than the final propagation. This allows us to | |
2164 | fold more conditionals here. */ | |
2165 | val = evaluate_stmt (stmt); | |
2166 | if (val.lattice_val != CONSTANT | |
796b6678 | 2167 | || val.mask != 0) |
94144e68 | 2168 | return false; |
2169 | ||
b7e55469 | 2170 | if (dump_file) |
2171 | { | |
2172 | fprintf (dump_file, "Folding predicate "); | |
2173 | print_gimple_expr (dump_file, stmt, 0, 0); | |
2174 | fprintf (dump_file, " to "); | |
2175 | print_generic_expr (dump_file, val.value, 0); | |
2176 | fprintf (dump_file, "\n"); | |
2177 | } | |
2178 | ||
94144e68 | 2179 | if (integer_zerop (val.value)) |
1a91d914 | 2180 | gimple_cond_make_false (cond_stmt); |
94144e68 | 2181 | else |
1a91d914 | 2182 | gimple_cond_make_true (cond_stmt); |
6688f8ec | 2183 | |
94144e68 | 2184 | return true; |
2185 | } | |
6688f8ec | 2186 | |
94144e68 | 2187 | case GIMPLE_CALL: |
2188 | { | |
2189 | tree lhs = gimple_call_lhs (stmt); | |
3064bb7b | 2190 | int flags = gimple_call_flags (stmt); |
15d138c9 | 2191 | tree val; |
94144e68 | 2192 | tree argt; |
2193 | bool changed = false; | |
2194 | unsigned i; | |
2195 | ||
2196 | /* If the call was folded into a constant make sure it goes | |
2197 | away even if we cannot propagate into all uses because of | |
2198 | type issues. */ | |
2199 | if (lhs | |
2200 | && TREE_CODE (lhs) == SSA_NAME | |
3064bb7b | 2201 | && (val = get_constant_value (lhs)) |
2202 | /* Don't optimize away calls that have side-effects. */ | |
2203 | && (flags & (ECF_CONST|ECF_PURE)) != 0 | |
2204 | && (flags & ECF_LOOPING_CONST_OR_PURE) == 0) | |
94144e68 | 2205 | { |
15d138c9 | 2206 | tree new_rhs = unshare_expr (val); |
338cce8f | 2207 | bool res; |
94144e68 | 2208 | if (!useless_type_conversion_p (TREE_TYPE (lhs), |
2209 | TREE_TYPE (new_rhs))) | |
2210 | new_rhs = fold_convert (TREE_TYPE (lhs), new_rhs); | |
338cce8f | 2211 | res = update_call_from_tree (gsi, new_rhs); |
2212 | gcc_assert (res); | |
94144e68 | 2213 | return true; |
2214 | } | |
2215 | ||
fb049fba | 2216 | /* Internal calls provide no argument types, so the extra laxity |
2217 | for normal calls does not apply. */ | |
2218 | if (gimple_call_internal_p (stmt)) | |
2219 | return false; | |
2220 | ||
581bf1c2 | 2221 | /* The heuristic of fold_builtin_alloca_with_align differs before and |
2222 | after inlining, so we don't require the arg to be changed into a | |
2223 | constant for folding, but just to be constant. */ | |
2224 | if (gimple_call_builtin_p (stmt, BUILT_IN_ALLOCA_WITH_ALIGN)) | |
9a65cc0a | 2225 | { |
581bf1c2 | 2226 | tree new_rhs = fold_builtin_alloca_with_align (stmt); |
6e93d308 | 2227 | if (new_rhs) |
2228 | { | |
2229 | bool res = update_call_from_tree (gsi, new_rhs); | |
582a80ed | 2230 | tree var = TREE_OPERAND (TREE_OPERAND (new_rhs, 0),0); |
6e93d308 | 2231 | gcc_assert (res); |
582a80ed | 2232 | insert_clobbers_for_var (*gsi, var); |
6e93d308 | 2233 | return true; |
2234 | } | |
9a65cc0a | 2235 | } |
2236 | ||
94144e68 | 2237 | /* Propagate into the call arguments. Compared to replace_uses_in |
2238 | this can use the argument slot types for type verification | |
2239 | instead of the current argument type. We also can safely | |
2240 | drop qualifiers here as we are dealing with constants anyway. */ | |
2de00a2d | 2241 | argt = TYPE_ARG_TYPES (gimple_call_fntype (stmt)); |
94144e68 | 2242 | for (i = 0; i < gimple_call_num_args (stmt) && argt; |
2243 | ++i, argt = TREE_CHAIN (argt)) | |
2244 | { | |
2245 | tree arg = gimple_call_arg (stmt, i); | |
2246 | if (TREE_CODE (arg) == SSA_NAME | |
15d138c9 | 2247 | && (val = get_constant_value (arg)) |
94144e68 | 2248 | && useless_type_conversion_p |
2249 | (TYPE_MAIN_VARIANT (TREE_VALUE (argt)), | |
15d138c9 | 2250 | TYPE_MAIN_VARIANT (TREE_TYPE (val)))) |
94144e68 | 2251 | { |
15d138c9 | 2252 | gimple_call_set_arg (stmt, i, unshare_expr (val)); |
94144e68 | 2253 | changed = true; |
2254 | } | |
2255 | } | |
e16f4c39 | 2256 | |
94144e68 | 2257 | return changed; |
2258 | } | |
6688f8ec | 2259 | |
6872bf3c | 2260 | case GIMPLE_ASSIGN: |
2261 | { | |
2262 | tree lhs = gimple_assign_lhs (stmt); | |
15d138c9 | 2263 | tree val; |
6872bf3c | 2264 | |
2265 | /* If we have a load that turned out to be constant replace it | |
2266 | as we cannot propagate into all uses in all cases. */ | |
2267 | if (gimple_assign_single_p (stmt) | |
2268 | && TREE_CODE (lhs) == SSA_NAME | |
15d138c9 | 2269 | && (val = get_constant_value (lhs))) |
6872bf3c | 2270 | { |
15d138c9 | 2271 | tree rhs = unshare_expr (val); |
6872bf3c | 2272 | if (!useless_type_conversion_p (TREE_TYPE (lhs), TREE_TYPE (rhs))) |
182cf5a9 | 2273 | rhs = fold_build1 (VIEW_CONVERT_EXPR, TREE_TYPE (lhs), rhs); |
6872bf3c | 2274 | gimple_assign_set_rhs_from_tree (gsi, rhs); |
2275 | return true; | |
2276 | } | |
2277 | ||
2278 | return false; | |
2279 | } | |
2280 | ||
94144e68 | 2281 | default: |
2282 | return false; | |
2283 | } | |
6688f8ec | 2284 | } |
2285 | ||
41511585 | 2286 | /* Visit the assignment statement STMT. Set the value of its LHS to the |
88dbf20f | 2287 | value computed by the RHS and store LHS in *OUTPUT_P. If STMT |
2288 | creates virtual definitions, set the value of each new name to that | |
75a70cf9 | 2289 | of the RHS (if we can derive a constant out of the RHS). |
2290 | Value-returning call statements also perform an assignment, and | |
2291 | are handled here. */ | |
4ee9c684 | 2292 | |
41511585 | 2293 | static enum ssa_prop_result |
42acab1c | 2294 | visit_assignment (gimple *stmt, tree *output_p) |
4ee9c684 | 2295 | { |
9908fe4d | 2296 | ccp_prop_value_t val; |
fc6cc27b | 2297 | enum ssa_prop_result retval = SSA_PROP_NOT_INTERESTING; |
4ee9c684 | 2298 | |
75a70cf9 | 2299 | tree lhs = gimple_get_lhs (stmt); |
88dbf20f | 2300 | if (TREE_CODE (lhs) == SSA_NAME) |
4ee9c684 | 2301 | { |
fc6cc27b | 2302 | /* Evaluate the statement, which could be |
2303 | either a GIMPLE_ASSIGN or a GIMPLE_CALL. */ | |
2304 | val = evaluate_stmt (stmt); | |
2305 | ||
88dbf20f | 2306 | /* If STMT is an assignment to an SSA_NAME, we only have one |
2307 | value to set. */ | |
27de3d43 | 2308 | if (set_lattice_value (lhs, &val)) |
88dbf20f | 2309 | { |
2310 | *output_p = lhs; | |
2311 | if (val.lattice_val == VARYING) | |
2312 | retval = SSA_PROP_VARYING; | |
2313 | else | |
2314 | retval = SSA_PROP_INTERESTING; | |
2315 | } | |
4ee9c684 | 2316 | } |
88dbf20f | 2317 | |
2318 | return retval; | |
4ee9c684 | 2319 | } |
2320 | ||
4ee9c684 | 2321 | |
41511585 | 2322 | /* Visit the conditional statement STMT. Return SSA_PROP_INTERESTING |
2323 | if it can determine which edge will be taken. Otherwise, return | |
2324 | SSA_PROP_VARYING. */ | |
2325 | ||
2326 | static enum ssa_prop_result | |
42acab1c | 2327 | visit_cond_stmt (gimple *stmt, edge *taken_edge_p) |
4ee9c684 | 2328 | { |
9908fe4d | 2329 | ccp_prop_value_t val; |
41511585 | 2330 | basic_block block; |
2331 | ||
75a70cf9 | 2332 | block = gimple_bb (stmt); |
41511585 | 2333 | val = evaluate_stmt (stmt); |
b7e55469 | 2334 | if (val.lattice_val != CONSTANT |
796b6678 | 2335 | || val.mask != 0) |
b7e55469 | 2336 | return SSA_PROP_VARYING; |
41511585 | 2337 | |
2338 | /* Find which edge out of the conditional block will be taken and add it | |
2339 | to the worklist. If no single edge can be determined statically, | |
2340 | return SSA_PROP_VARYING to feed all the outgoing edges to the | |
2341 | propagation engine. */ | |
b7e55469 | 2342 | *taken_edge_p = find_taken_edge (block, val.value); |
41511585 | 2343 | if (*taken_edge_p) |
2344 | return SSA_PROP_INTERESTING; | |
2345 | else | |
2346 | return SSA_PROP_VARYING; | |
4ee9c684 | 2347 | } |
2348 | ||
4ee9c684 | 2349 | |
41511585 | 2350 | /* Evaluate statement STMT. If the statement produces an output value and |
2351 | its evaluation changes the lattice value of its output, return | |
2352 | SSA_PROP_INTERESTING and set *OUTPUT_P to the SSA_NAME holding the | |
2353 | output value. | |
48e1416a | 2354 | |
41511585 | 2355 | If STMT is a conditional branch and we can determine its truth |
2356 | value, set *TAKEN_EDGE_P accordingly. If STMT produces a varying | |
2357 | value, return SSA_PROP_VARYING. */ | |
4ee9c684 | 2358 | |
41511585 | 2359 | static enum ssa_prop_result |
42acab1c | 2360 | ccp_visit_stmt (gimple *stmt, edge *taken_edge_p, tree *output_p) |
41511585 | 2361 | { |
41511585 | 2362 | tree def; |
2363 | ssa_op_iter iter; | |
4ee9c684 | 2364 | |
41511585 | 2365 | if (dump_file && (dump_flags & TDF_DETAILS)) |
4ee9c684 | 2366 | { |
88dbf20f | 2367 | fprintf (dump_file, "\nVisiting statement:\n"); |
75a70cf9 | 2368 | print_gimple_stmt (dump_file, stmt, 0, dump_flags); |
4ee9c684 | 2369 | } |
4ee9c684 | 2370 | |
75a70cf9 | 2371 | switch (gimple_code (stmt)) |
4ee9c684 | 2372 | { |
75a70cf9 | 2373 | case GIMPLE_ASSIGN: |
2374 | /* If the statement is an assignment that produces a single | |
2375 | output value, evaluate its RHS to see if the lattice value of | |
2376 | its output has changed. */ | |
2377 | return visit_assignment (stmt, output_p); | |
2378 | ||
2379 | case GIMPLE_CALL: | |
2380 | /* A value-returning call also performs an assignment. */ | |
2381 | if (gimple_call_lhs (stmt) != NULL_TREE) | |
2382 | return visit_assignment (stmt, output_p); | |
2383 | break; | |
2384 | ||
2385 | case GIMPLE_COND: | |
2386 | case GIMPLE_SWITCH: | |
2387 | /* If STMT is a conditional branch, see if we can determine | |
2388 | which branch will be taken. */ | |
2389 | /* FIXME. It appears that we should be able to optimize | |
2390 | computed GOTOs here as well. */ | |
2391 | return visit_cond_stmt (stmt, taken_edge_p); | |
2392 | ||
2393 | default: | |
2394 | break; | |
4ee9c684 | 2395 | } |
4ee9c684 | 2396 | |
41511585 | 2397 | /* Any other kind of statement is not interesting for constant |
2398 | propagation and, therefore, not worth simulating. */ | |
41511585 | 2399 | if (dump_file && (dump_flags & TDF_DETAILS)) |
2400 | fprintf (dump_file, "No interesting values produced. Marked VARYING.\n"); | |
4ee9c684 | 2401 | |
41511585 | 2402 | /* Definitions made by statements other than assignments to |
2403 | SSA_NAMEs represent unknown modifications to their outputs. | |
2404 | Mark them VARYING. */ | |
88dbf20f | 2405 | FOR_EACH_SSA_TREE_OPERAND (def, stmt, iter, SSA_OP_ALL_DEFS) |
27de3d43 | 2406 | set_value_varying (def); |
4ee9c684 | 2407 | |
41511585 | 2408 | return SSA_PROP_VARYING; |
2409 | } | |
4ee9c684 | 2410 | |
4ee9c684 | 2411 | |
d0322b7d | 2412 | /* Main entry point for SSA Conditional Constant Propagation. If NONZERO_P, |
2413 | record nonzero bits. */ | |
41511585 | 2414 | |
33a34f1e | 2415 | static unsigned int |
d0322b7d | 2416 | do_ssa_ccp (bool nonzero_p) |
41511585 | 2417 | { |
582a80ed | 2418 | unsigned int todo = 0; |
2419 | calculate_dominance_info (CDI_DOMINATORS); | |
e2588447 | 2420 | |
41511585 | 2421 | ccp_initialize (); |
2422 | ssa_propagate (ccp_visit_stmt, ccp_visit_phi_node); | |
a54071b2 | 2423 | if (ccp_finalize (nonzero_p || flag_ipa_bit_cp)) |
e2588447 | 2424 | { |
2425 | todo = (TODO_cleanup_cfg | TODO_update_ssa); | |
2426 | ||
2427 | /* ccp_finalize does not preserve loop-closed ssa. */ | |
2428 | loops_state_clear (LOOP_CLOSED_SSA); | |
2429 | } | |
2430 | ||
582a80ed | 2431 | free_dominance_info (CDI_DOMINATORS); |
2432 | return todo; | |
4ee9c684 | 2433 | } |
2434 | ||
5664499b | 2435 | |
cbe8bda8 | 2436 | namespace { |
2437 | ||
2438 | const pass_data pass_data_ccp = | |
41511585 | 2439 | { |
cbe8bda8 | 2440 | GIMPLE_PASS, /* type */ |
2441 | "ccp", /* name */ | |
2442 | OPTGROUP_NONE, /* optinfo_flags */ | |
cbe8bda8 | 2443 | TV_TREE_CCP, /* tv_id */ |
2444 | ( PROP_cfg | PROP_ssa ), /* properties_required */ | |
2445 | 0, /* properties_provided */ | |
2446 | 0, /* properties_destroyed */ | |
2447 | 0, /* todo_flags_start */ | |
8b88439e | 2448 | TODO_update_address_taken, /* todo_flags_finish */ |
41511585 | 2449 | }; |
4ee9c684 | 2450 | |
cbe8bda8 | 2451 | class pass_ccp : public gimple_opt_pass |
2452 | { | |
2453 | public: | |
9af5ce0c | 2454 | pass_ccp (gcc::context *ctxt) |
d0322b7d | 2455 | : gimple_opt_pass (pass_data_ccp, ctxt), nonzero_p (false) |
cbe8bda8 | 2456 | {} |
2457 | ||
2458 | /* opt_pass methods: */ | |
ae84f584 | 2459 | opt_pass * clone () { return new pass_ccp (m_ctxt); } |
d0322b7d | 2460 | void set_pass_param (unsigned int n, bool param) |
2461 | { | |
2462 | gcc_assert (n == 0); | |
2463 | nonzero_p = param; | |
2464 | } | |
31315c24 | 2465 | virtual bool gate (function *) { return flag_tree_ccp != 0; } |
d0322b7d | 2466 | virtual unsigned int execute (function *) { return do_ssa_ccp (nonzero_p); } |
cbe8bda8 | 2467 | |
d0322b7d | 2468 | private: |
2469 | /* Determines whether the pass instance records nonzero bits. */ | |
2470 | bool nonzero_p; | |
cbe8bda8 | 2471 | }; // class pass_ccp |
2472 | ||
2473 | } // anon namespace | |
2474 | ||
2475 | gimple_opt_pass * | |
2476 | make_pass_ccp (gcc::context *ctxt) | |
2477 | { | |
2478 | return new pass_ccp (ctxt); | |
2479 | } | |
2480 | ||
4ee9c684 | 2481 | |
75a70cf9 | 2482 | |
bdd0e199 | 2483 | /* Try to optimize out __builtin_stack_restore. Optimize it out |
2484 | if there is another __builtin_stack_restore in the same basic | |
2485 | block and no calls or ASM_EXPRs are in between, or if this block's | |
2486 | only outgoing edge is to EXIT_BLOCK and there are no calls or | |
2487 | ASM_EXPRs after this __builtin_stack_restore. */ | |
2488 | ||
2489 | static tree | |
75a70cf9 | 2490 | optimize_stack_restore (gimple_stmt_iterator i) |
bdd0e199 | 2491 | { |
6ea999da | 2492 | tree callee; |
42acab1c | 2493 | gimple *stmt; |
75a70cf9 | 2494 | |
2495 | basic_block bb = gsi_bb (i); | |
42acab1c | 2496 | gimple *call = gsi_stmt (i); |
bdd0e199 | 2497 | |
75a70cf9 | 2498 | if (gimple_code (call) != GIMPLE_CALL |
2499 | || gimple_call_num_args (call) != 1 | |
2500 | || TREE_CODE (gimple_call_arg (call, 0)) != SSA_NAME | |
2501 | || !POINTER_TYPE_P (TREE_TYPE (gimple_call_arg (call, 0)))) | |
bdd0e199 | 2502 | return NULL_TREE; |
2503 | ||
75a70cf9 | 2504 | for (gsi_next (&i); !gsi_end_p (i); gsi_next (&i)) |
bdd0e199 | 2505 | { |
75a70cf9 | 2506 | stmt = gsi_stmt (i); |
2507 | if (gimple_code (stmt) == GIMPLE_ASM) | |
bdd0e199 | 2508 | return NULL_TREE; |
75a70cf9 | 2509 | if (gimple_code (stmt) != GIMPLE_CALL) |
bdd0e199 | 2510 | continue; |
2511 | ||
75a70cf9 | 2512 | callee = gimple_call_fndecl (stmt); |
c40a6f90 | 2513 | if (!callee |
2514 | || DECL_BUILT_IN_CLASS (callee) != BUILT_IN_NORMAL | |
2515 | /* All regular builtins are ok, just obviously not alloca. */ | |
581bf1c2 | 2516 | || DECL_FUNCTION_CODE (callee) == BUILT_IN_ALLOCA |
2517 | || DECL_FUNCTION_CODE (callee) == BUILT_IN_ALLOCA_WITH_ALIGN) | |
bdd0e199 | 2518 | return NULL_TREE; |
2519 | ||
2520 | if (DECL_FUNCTION_CODE (callee) == BUILT_IN_STACK_RESTORE) | |
6ea999da | 2521 | goto second_stack_restore; |
bdd0e199 | 2522 | } |
2523 | ||
6ea999da | 2524 | if (!gsi_end_p (i)) |
bdd0e199 | 2525 | return NULL_TREE; |
2526 | ||
6ea999da | 2527 | /* Allow one successor of the exit block, or zero successors. */ |
2528 | switch (EDGE_COUNT (bb->succs)) | |
2529 | { | |
2530 | case 0: | |
2531 | break; | |
2532 | case 1: | |
34154e27 | 2533 | if (single_succ_edge (bb)->dest != EXIT_BLOCK_PTR_FOR_FN (cfun)) |
6ea999da | 2534 | return NULL_TREE; |
2535 | break; | |
2536 | default: | |
2537 | return NULL_TREE; | |
2538 | } | |
2539 | second_stack_restore: | |
bdd0e199 | 2540 | |
6ea999da | 2541 | /* If there's exactly one use, then zap the call to __builtin_stack_save. |
2542 | If there are multiple uses, then the last one should remove the call. | |
2543 | In any case, whether the call to __builtin_stack_save can be removed | |
2544 | or not is irrelevant to removing the call to __builtin_stack_restore. */ | |
2545 | if (has_single_use (gimple_call_arg (call, 0))) | |
2546 | { | |
42acab1c | 2547 | gimple *stack_save = SSA_NAME_DEF_STMT (gimple_call_arg (call, 0)); |
6ea999da | 2548 | if (is_gimple_call (stack_save)) |
2549 | { | |
2550 | callee = gimple_call_fndecl (stack_save); | |
2551 | if (callee | |
2552 | && DECL_BUILT_IN_CLASS (callee) == BUILT_IN_NORMAL | |
2553 | && DECL_FUNCTION_CODE (callee) == BUILT_IN_STACK_SAVE) | |
2554 | { | |
2555 | gimple_stmt_iterator stack_save_gsi; | |
2556 | tree rhs; | |
bdd0e199 | 2557 | |
6ea999da | 2558 | stack_save_gsi = gsi_for_stmt (stack_save); |
2559 | rhs = build_int_cst (TREE_TYPE (gimple_call_arg (call, 0)), 0); | |
2560 | update_call_from_tree (&stack_save_gsi, rhs); | |
2561 | } | |
2562 | } | |
2563 | } | |
bdd0e199 | 2564 | |
75a70cf9 | 2565 | /* No effect, so the statement will be deleted. */ |
bdd0e199 | 2566 | return integer_zero_node; |
2567 | } | |
75a70cf9 | 2568 | |
8a58ed0a | 2569 | /* If va_list type is a simple pointer and nothing special is needed, |
2570 | optimize __builtin_va_start (&ap, 0) into ap = __builtin_next_arg (0), | |
2571 | __builtin_va_end (&ap) out as NOP and __builtin_va_copy into a simple | |
2572 | pointer assignment. */ | |
2573 | ||
2574 | static tree | |
42acab1c | 2575 | optimize_stdarg_builtin (gimple *call) |
8a58ed0a | 2576 | { |
5f57a8b1 | 2577 | tree callee, lhs, rhs, cfun_va_list; |
8a58ed0a | 2578 | bool va_list_simple_ptr; |
389dd41b | 2579 | location_t loc = gimple_location (call); |
8a58ed0a | 2580 | |
75a70cf9 | 2581 | if (gimple_code (call) != GIMPLE_CALL) |
8a58ed0a | 2582 | return NULL_TREE; |
2583 | ||
75a70cf9 | 2584 | callee = gimple_call_fndecl (call); |
5f57a8b1 | 2585 | |
2586 | cfun_va_list = targetm.fn_abi_va_list (callee); | |
2587 | va_list_simple_ptr = POINTER_TYPE_P (cfun_va_list) | |
2588 | && (TREE_TYPE (cfun_va_list) == void_type_node | |
2589 | || TREE_TYPE (cfun_va_list) == char_type_node); | |
2590 | ||
8a58ed0a | 2591 | switch (DECL_FUNCTION_CODE (callee)) |
2592 | { | |
2593 | case BUILT_IN_VA_START: | |
2594 | if (!va_list_simple_ptr | |
2595 | || targetm.expand_builtin_va_start != NULL | |
e7ed5dd7 | 2596 | || !builtin_decl_explicit_p (BUILT_IN_NEXT_ARG)) |
8a58ed0a | 2597 | return NULL_TREE; |
2598 | ||
75a70cf9 | 2599 | if (gimple_call_num_args (call) != 2) |
8a58ed0a | 2600 | return NULL_TREE; |
2601 | ||
75a70cf9 | 2602 | lhs = gimple_call_arg (call, 0); |
8a58ed0a | 2603 | if (!POINTER_TYPE_P (TREE_TYPE (lhs)) |
2604 | || TYPE_MAIN_VARIANT (TREE_TYPE (TREE_TYPE (lhs))) | |
5f57a8b1 | 2605 | != TYPE_MAIN_VARIANT (cfun_va_list)) |
8a58ed0a | 2606 | return NULL_TREE; |
48e1416a | 2607 | |
389dd41b | 2608 | lhs = build_fold_indirect_ref_loc (loc, lhs); |
b9a16870 | 2609 | rhs = build_call_expr_loc (loc, builtin_decl_explicit (BUILT_IN_NEXT_ARG), |
75a70cf9 | 2610 | 1, integer_zero_node); |
389dd41b | 2611 | rhs = fold_convert_loc (loc, TREE_TYPE (lhs), rhs); |
8a58ed0a | 2612 | return build2 (MODIFY_EXPR, TREE_TYPE (lhs), lhs, rhs); |
2613 | ||
2614 | case BUILT_IN_VA_COPY: | |
2615 | if (!va_list_simple_ptr) | |
2616 | return NULL_TREE; | |
2617 | ||
75a70cf9 | 2618 | if (gimple_call_num_args (call) != 2) |
8a58ed0a | 2619 | return NULL_TREE; |
2620 | ||
75a70cf9 | 2621 | lhs = gimple_call_arg (call, 0); |
8a58ed0a | 2622 | if (!POINTER_TYPE_P (TREE_TYPE (lhs)) |
2623 | || TYPE_MAIN_VARIANT (TREE_TYPE (TREE_TYPE (lhs))) | |
5f57a8b1 | 2624 | != TYPE_MAIN_VARIANT (cfun_va_list)) |
8a58ed0a | 2625 | return NULL_TREE; |
2626 | ||
389dd41b | 2627 | lhs = build_fold_indirect_ref_loc (loc, lhs); |
75a70cf9 | 2628 | rhs = gimple_call_arg (call, 1); |
8a58ed0a | 2629 | if (TYPE_MAIN_VARIANT (TREE_TYPE (rhs)) |
5f57a8b1 | 2630 | != TYPE_MAIN_VARIANT (cfun_va_list)) |
8a58ed0a | 2631 | return NULL_TREE; |
2632 | ||
389dd41b | 2633 | rhs = fold_convert_loc (loc, TREE_TYPE (lhs), rhs); |
8a58ed0a | 2634 | return build2 (MODIFY_EXPR, TREE_TYPE (lhs), lhs, rhs); |
2635 | ||
2636 | case BUILT_IN_VA_END: | |
75a70cf9 | 2637 | /* No effect, so the statement will be deleted. */ |
8a58ed0a | 2638 | return integer_zero_node; |
2639 | ||
2640 | default: | |
2641 | gcc_unreachable (); | |
2642 | } | |
2643 | } | |
75a70cf9 | 2644 | |
f87df69a | 2645 | /* Attemp to make the block of __builtin_unreachable I unreachable by changing |
2646 | the incoming jumps. Return true if at least one jump was changed. */ | |
2647 | ||
2648 | static bool | |
2649 | optimize_unreachable (gimple_stmt_iterator i) | |
2650 | { | |
2651 | basic_block bb = gsi_bb (i); | |
2652 | gimple_stmt_iterator gsi; | |
42acab1c | 2653 | gimple *stmt; |
f87df69a | 2654 | edge_iterator ei; |
2655 | edge e; | |
2656 | bool ret; | |
2657 | ||
f6b540af | 2658 | if (flag_sanitize & SANITIZE_UNREACHABLE) |
2659 | return false; | |
2660 | ||
f87df69a | 2661 | for (gsi = gsi_start_bb (bb); !gsi_end_p (gsi); gsi_next (&gsi)) |
2662 | { | |
2663 | stmt = gsi_stmt (gsi); | |
2664 | ||
2665 | if (is_gimple_debug (stmt)) | |
2666 | continue; | |
2667 | ||
1a91d914 | 2668 | if (glabel *label_stmt = dyn_cast <glabel *> (stmt)) |
f87df69a | 2669 | { |
2670 | /* Verify we do not need to preserve the label. */ | |
1a91d914 | 2671 | if (FORCED_LABEL (gimple_label_label (label_stmt))) |
f87df69a | 2672 | return false; |
2673 | ||
2674 | continue; | |
2675 | } | |
2676 | ||
2677 | /* Only handle the case that __builtin_unreachable is the first statement | |
2678 | in the block. We rely on DCE to remove stmts without side-effects | |
2679 | before __builtin_unreachable. */ | |
2680 | if (gsi_stmt (gsi) != gsi_stmt (i)) | |
2681 | return false; | |
2682 | } | |
2683 | ||
2684 | ret = false; | |
2685 | FOR_EACH_EDGE (e, ei, bb->preds) | |
2686 | { | |
2687 | gsi = gsi_last_bb (e->src); | |
522f73a1 | 2688 | if (gsi_end_p (gsi)) |
2689 | continue; | |
f87df69a | 2690 | |
522f73a1 | 2691 | stmt = gsi_stmt (gsi); |
1a91d914 | 2692 | if (gcond *cond_stmt = dyn_cast <gcond *> (stmt)) |
f87df69a | 2693 | { |
2694 | if (e->flags & EDGE_TRUE_VALUE) | |
1a91d914 | 2695 | gimple_cond_make_false (cond_stmt); |
f87df69a | 2696 | else if (e->flags & EDGE_FALSE_VALUE) |
1a91d914 | 2697 | gimple_cond_make_true (cond_stmt); |
f87df69a | 2698 | else |
2699 | gcc_unreachable (); | |
1a91d914 | 2700 | update_stmt (cond_stmt); |
f87df69a | 2701 | } |
2702 | else | |
2703 | { | |
2704 | /* Todo: handle other cases, f.i. switch statement. */ | |
2705 | continue; | |
2706 | } | |
2707 | ||
2708 | ret = true; | |
2709 | } | |
2710 | ||
2711 | return ret; | |
2712 | } | |
2713 | ||
9c1a31e4 | 2714 | /* Optimize |
2715 | mask_2 = 1 << cnt_1; | |
2716 | _4 = __atomic_fetch_or_* (ptr_6, mask_2, _3); | |
2717 | _5 = _4 & mask_2; | |
2718 | to | |
2719 | _4 = ATOMIC_BIT_TEST_AND_SET (ptr_6, cnt_1, 0, _3); | |
2720 | _5 = _4; | |
2721 | If _5 is only used in _5 != 0 or _5 == 0 comparisons, 1 | |
2722 | is passed instead of 0, and the builtin just returns a zero | |
2723 | or 1 value instead of the actual bit. | |
2724 | Similarly for __sync_fetch_and_or_* (without the ", _3" part | |
2725 | in there), and/or if mask_2 is a power of 2 constant. | |
2726 | Similarly for xor instead of or, use ATOMIC_BIT_TEST_AND_COMPLEMENT | |
2727 | in that case. And similarly for and instead of or, except that | |
2728 | the second argument to the builtin needs to be one's complement | |
2729 | of the mask instead of mask. */ | |
2730 | ||
2731 | static void | |
2732 | optimize_atomic_bit_test_and (gimple_stmt_iterator *gsip, | |
2733 | enum internal_fn fn, bool has_model_arg, | |
2734 | bool after) | |
2735 | { | |
2736 | gimple *call = gsi_stmt (*gsip); | |
2737 | tree lhs = gimple_call_lhs (call); | |
2738 | use_operand_p use_p; | |
2739 | gimple *use_stmt; | |
2740 | tree mask, bit; | |
2741 | optab optab; | |
2742 | ||
2743 | if (!flag_inline_atomics | |
2744 | || optimize_debug | |
2745 | || !gimple_call_builtin_p (call, BUILT_IN_NORMAL) | |
2746 | || !lhs | |
2747 | || SSA_NAME_OCCURS_IN_ABNORMAL_PHI (lhs) | |
2748 | || !single_imm_use (lhs, &use_p, &use_stmt) | |
2749 | || !is_gimple_assign (use_stmt) | |
2750 | || gimple_assign_rhs_code (use_stmt) != BIT_AND_EXPR | |
2751 | || !gimple_vdef (call)) | |
2752 | return; | |
2753 | ||
2754 | switch (fn) | |
2755 | { | |
2756 | case IFN_ATOMIC_BIT_TEST_AND_SET: | |
2757 | optab = atomic_bit_test_and_set_optab; | |
2758 | break; | |
2759 | case IFN_ATOMIC_BIT_TEST_AND_COMPLEMENT: | |
2760 | optab = atomic_bit_test_and_complement_optab; | |
2761 | break; | |
2762 | case IFN_ATOMIC_BIT_TEST_AND_RESET: | |
2763 | optab = atomic_bit_test_and_reset_optab; | |
2764 | break; | |
2765 | default: | |
2766 | return; | |
2767 | } | |
2768 | ||
2769 | if (optab_handler (optab, TYPE_MODE (TREE_TYPE (lhs))) == CODE_FOR_nothing) | |
2770 | return; | |
2771 | ||
2772 | mask = gimple_call_arg (call, 1); | |
2773 | tree use_lhs = gimple_assign_lhs (use_stmt); | |
2774 | if (!use_lhs) | |
2775 | return; | |
2776 | ||
2777 | if (TREE_CODE (mask) == INTEGER_CST) | |
2778 | { | |
2779 | if (fn == IFN_ATOMIC_BIT_TEST_AND_RESET) | |
2780 | mask = const_unop (BIT_NOT_EXPR, TREE_TYPE (mask), mask); | |
2781 | mask = fold_convert (TREE_TYPE (lhs), mask); | |
2782 | int ibit = tree_log2 (mask); | |
2783 | if (ibit < 0) | |
2784 | return; | |
2785 | bit = build_int_cst (TREE_TYPE (lhs), ibit); | |
2786 | } | |
2787 | else if (TREE_CODE (mask) == SSA_NAME) | |
2788 | { | |
2789 | gimple *g = SSA_NAME_DEF_STMT (mask); | |
2790 | if (fn == IFN_ATOMIC_BIT_TEST_AND_RESET) | |
2791 | { | |
2792 | if (!is_gimple_assign (g) | |
2793 | || gimple_assign_rhs_code (g) != BIT_NOT_EXPR) | |
2794 | return; | |
2795 | mask = gimple_assign_rhs1 (g); | |
2796 | if (TREE_CODE (mask) != SSA_NAME) | |
2797 | return; | |
2798 | g = SSA_NAME_DEF_STMT (mask); | |
2799 | } | |
2800 | if (!is_gimple_assign (g) | |
2801 | || gimple_assign_rhs_code (g) != LSHIFT_EXPR | |
2802 | || !integer_onep (gimple_assign_rhs1 (g))) | |
2803 | return; | |
2804 | bit = gimple_assign_rhs2 (g); | |
2805 | } | |
2806 | else | |
2807 | return; | |
2808 | ||
2809 | if (gimple_assign_rhs1 (use_stmt) == lhs) | |
2810 | { | |
2811 | if (!operand_equal_p (gimple_assign_rhs2 (use_stmt), mask, 0)) | |
2812 | return; | |
2813 | } | |
2814 | else if (gimple_assign_rhs2 (use_stmt) != lhs | |
2815 | || !operand_equal_p (gimple_assign_rhs1 (use_stmt), mask, 0)) | |
2816 | return; | |
2817 | ||
2818 | bool use_bool = true; | |
2819 | bool has_debug_uses = false; | |
2820 | imm_use_iterator iter; | |
2821 | gimple *g; | |
2822 | ||
2823 | if (SSA_NAME_OCCURS_IN_ABNORMAL_PHI (use_lhs)) | |
2824 | use_bool = false; | |
2825 | FOR_EACH_IMM_USE_STMT (g, iter, use_lhs) | |
2826 | { | |
2827 | enum tree_code code = ERROR_MARK; | |
7b645785 | 2828 | tree op0 = NULL_TREE, op1 = NULL_TREE; |
9c1a31e4 | 2829 | if (is_gimple_debug (g)) |
2830 | { | |
2831 | has_debug_uses = true; | |
2832 | continue; | |
2833 | } | |
2834 | else if (is_gimple_assign (g)) | |
2835 | switch (gimple_assign_rhs_code (g)) | |
2836 | { | |
2837 | case COND_EXPR: | |
2838 | op1 = gimple_assign_rhs1 (g); | |
2839 | code = TREE_CODE (op1); | |
2840 | op0 = TREE_OPERAND (op1, 0); | |
2841 | op1 = TREE_OPERAND (op1, 1); | |
2842 | break; | |
2843 | case EQ_EXPR: | |
2844 | case NE_EXPR: | |
2845 | code = gimple_assign_rhs_code (g); | |
2846 | op0 = gimple_assign_rhs1 (g); | |
2847 | op1 = gimple_assign_rhs2 (g); | |
2848 | break; | |
2849 | default: | |
2850 | break; | |
2851 | } | |
2852 | else if (gimple_code (g) == GIMPLE_COND) | |
2853 | { | |
2854 | code = gimple_cond_code (g); | |
2855 | op0 = gimple_cond_lhs (g); | |
2856 | op1 = gimple_cond_rhs (g); | |
2857 | } | |
2858 | ||
2859 | if ((code == EQ_EXPR || code == NE_EXPR) | |
2860 | && op0 == use_lhs | |
2861 | && integer_zerop (op1)) | |
2862 | { | |
2863 | use_operand_p use_p; | |
2864 | int n = 0; | |
2865 | FOR_EACH_IMM_USE_ON_STMT (use_p, iter) | |
2866 | n++; | |
2867 | if (n == 1) | |
2868 | continue; | |
2869 | } | |
2870 | ||
2871 | use_bool = false; | |
2872 | BREAK_FROM_IMM_USE_STMT (iter); | |
2873 | } | |
2874 | ||
2875 | tree new_lhs = make_ssa_name (TREE_TYPE (lhs)); | |
2876 | tree flag = build_int_cst (TREE_TYPE (lhs), use_bool); | |
2877 | if (has_model_arg) | |
2878 | g = gimple_build_call_internal (fn, 4, gimple_call_arg (call, 0), | |
2879 | bit, flag, gimple_call_arg (call, 2)); | |
2880 | else | |
2881 | g = gimple_build_call_internal (fn, 3, gimple_call_arg (call, 0), | |
2882 | bit, flag); | |
2883 | gimple_call_set_lhs (g, new_lhs); | |
2884 | gimple_set_location (g, gimple_location (call)); | |
2885 | gimple_set_vuse (g, gimple_vuse (call)); | |
2886 | gimple_set_vdef (g, gimple_vdef (call)); | |
2887 | SSA_NAME_DEF_STMT (gimple_vdef (call)) = g; | |
2888 | gimple_stmt_iterator gsi = *gsip; | |
2889 | gsi_insert_after (&gsi, g, GSI_NEW_STMT); | |
2890 | if (after) | |
2891 | { | |
2892 | /* The internal function returns the value of the specified bit | |
2893 | before the atomic operation. If we are interested in the value | |
2894 | of the specified bit after the atomic operation (makes only sense | |
2895 | for xor, otherwise the bit content is compile time known), | |
2896 | we need to invert the bit. */ | |
2897 | g = gimple_build_assign (make_ssa_name (TREE_TYPE (lhs)), | |
2898 | BIT_XOR_EXPR, new_lhs, | |
2899 | use_bool ? build_int_cst (TREE_TYPE (lhs), 1) | |
2900 | : mask); | |
2901 | new_lhs = gimple_assign_lhs (g); | |
2902 | gsi_insert_after (&gsi, g, GSI_NEW_STMT); | |
2903 | } | |
2904 | if (use_bool && has_debug_uses) | |
2905 | { | |
2906 | tree temp = make_node (DEBUG_EXPR_DECL); | |
2907 | DECL_ARTIFICIAL (temp) = 1; | |
2908 | TREE_TYPE (temp) = TREE_TYPE (lhs); | |
2909 | DECL_MODE (temp) = TYPE_MODE (TREE_TYPE (lhs)); | |
2910 | tree t = build2 (LSHIFT_EXPR, TREE_TYPE (lhs), new_lhs, bit); | |
2911 | g = gimple_build_debug_bind (temp, t, g); | |
2912 | gsi_insert_after (&gsi, g, GSI_NEW_STMT); | |
2913 | FOR_EACH_IMM_USE_STMT (g, iter, use_lhs) | |
2914 | if (is_gimple_debug (g)) | |
2915 | { | |
2916 | use_operand_p use_p; | |
2917 | FOR_EACH_IMM_USE_ON_STMT (use_p, iter) | |
2918 | SET_USE (use_p, temp); | |
2919 | update_stmt (g); | |
2920 | } | |
2921 | } | |
2922 | SSA_NAME_OCCURS_IN_ABNORMAL_PHI (new_lhs) | |
2923 | = SSA_NAME_OCCURS_IN_ABNORMAL_PHI (use_lhs); | |
2924 | replace_uses_by (use_lhs, new_lhs); | |
2925 | gsi = gsi_for_stmt (use_stmt); | |
2926 | gsi_remove (&gsi, true); | |
2927 | release_defs (use_stmt); | |
2928 | gsi_remove (gsip, true); | |
2929 | release_ssa_name (lhs); | |
2930 | } | |
2931 | ||
4ee9c684 | 2932 | /* A simple pass that attempts to fold all builtin functions. This pass |
2933 | is run after we've propagated as many constants as we can. */ | |
2934 | ||
65b0537f | 2935 | namespace { |
2936 | ||
2937 | const pass_data pass_data_fold_builtins = | |
2938 | { | |
2939 | GIMPLE_PASS, /* type */ | |
2940 | "fab", /* name */ | |
2941 | OPTGROUP_NONE, /* optinfo_flags */ | |
65b0537f | 2942 | TV_NONE, /* tv_id */ |
2943 | ( PROP_cfg | PROP_ssa ), /* properties_required */ | |
2944 | 0, /* properties_provided */ | |
2945 | 0, /* properties_destroyed */ | |
2946 | 0, /* todo_flags_start */ | |
8b88439e | 2947 | TODO_update_ssa, /* todo_flags_finish */ |
65b0537f | 2948 | }; |
2949 | ||
2950 | class pass_fold_builtins : public gimple_opt_pass | |
2951 | { | |
2952 | public: | |
2953 | pass_fold_builtins (gcc::context *ctxt) | |
2954 | : gimple_opt_pass (pass_data_fold_builtins, ctxt) | |
2955 | {} | |
2956 | ||
2957 | /* opt_pass methods: */ | |
2958 | opt_pass * clone () { return new pass_fold_builtins (m_ctxt); } | |
2959 | virtual unsigned int execute (function *); | |
2960 | ||
2961 | }; // class pass_fold_builtins | |
2962 | ||
2963 | unsigned int | |
2964 | pass_fold_builtins::execute (function *fun) | |
4ee9c684 | 2965 | { |
b36237eb | 2966 | bool cfg_changed = false; |
4ee9c684 | 2967 | basic_block bb; |
b1b7c0c4 | 2968 | unsigned int todoflags = 0; |
48e1416a | 2969 | |
65b0537f | 2970 | FOR_EACH_BB_FN (bb, fun) |
4ee9c684 | 2971 | { |
75a70cf9 | 2972 | gimple_stmt_iterator i; |
2973 | for (i = gsi_start_bb (bb); !gsi_end_p (i); ) | |
4ee9c684 | 2974 | { |
42acab1c | 2975 | gimple *stmt, *old_stmt; |
40a3eb84 | 2976 | tree callee; |
0a39fd54 | 2977 | enum built_in_function fcode; |
4ee9c684 | 2978 | |
75a70cf9 | 2979 | stmt = gsi_stmt (i); |
2980 | ||
2981 | if (gimple_code (stmt) != GIMPLE_CALL) | |
0a39fd54 | 2982 | { |
896a0c42 | 2983 | /* Remove all *ssaname_N ={v} {CLOBBER}; stmts, |
2984 | after the last GIMPLE DSE they aren't needed and might | |
2985 | unnecessarily keep the SSA_NAMEs live. */ | |
2986 | if (gimple_clobber_p (stmt)) | |
2987 | { | |
2988 | tree lhs = gimple_assign_lhs (stmt); | |
2989 | if (TREE_CODE (lhs) == MEM_REF | |
2990 | && TREE_CODE (TREE_OPERAND (lhs, 0)) == SSA_NAME) | |
2991 | { | |
2992 | unlink_stmt_vdef (stmt); | |
2993 | gsi_remove (&i, true); | |
2994 | release_defs (stmt); | |
2995 | continue; | |
2996 | } | |
2997 | } | |
75a70cf9 | 2998 | gsi_next (&i); |
0a39fd54 | 2999 | continue; |
3000 | } | |
40a3eb84 | 3001 | |
75a70cf9 | 3002 | callee = gimple_call_fndecl (stmt); |
4ee9c684 | 3003 | if (!callee || DECL_BUILT_IN_CLASS (callee) != BUILT_IN_NORMAL) |
0a39fd54 | 3004 | { |
75a70cf9 | 3005 | gsi_next (&i); |
0a39fd54 | 3006 | continue; |
3007 | } | |
5a4b7e1e | 3008 | |
40a3eb84 | 3009 | fcode = DECL_FUNCTION_CODE (callee); |
3010 | if (fold_stmt (&i)) | |
3011 | ; | |
3012 | else | |
3013 | { | |
3014 | tree result = NULL_TREE; | |
3015 | switch (DECL_FUNCTION_CODE (callee)) | |
3016 | { | |
3017 | case BUILT_IN_CONSTANT_P: | |
3018 | /* Resolve __builtin_constant_p. If it hasn't been | |
3019 | folded to integer_one_node by now, it's fairly | |
3020 | certain that the value simply isn't constant. */ | |
3021 | result = integer_zero_node; | |
3022 | break; | |
5a4b7e1e | 3023 | |
40a3eb84 | 3024 | case BUILT_IN_ASSUME_ALIGNED: |
3025 | /* Remove __builtin_assume_aligned. */ | |
3026 | result = gimple_call_arg (stmt, 0); | |
3027 | break; | |
4ee9c684 | 3028 | |
40a3eb84 | 3029 | case BUILT_IN_STACK_RESTORE: |
3030 | result = optimize_stack_restore (i); | |
3031 | if (result) | |
3032 | break; | |
3033 | gsi_next (&i); | |
3034 | continue; | |
fca0886c | 3035 | |
40a3eb84 | 3036 | case BUILT_IN_UNREACHABLE: |
3037 | if (optimize_unreachable (i)) | |
3038 | cfg_changed = true; | |
8a58ed0a | 3039 | break; |
8a58ed0a | 3040 | |
9c1a31e4 | 3041 | case BUILT_IN_ATOMIC_FETCH_OR_1: |
3042 | case BUILT_IN_ATOMIC_FETCH_OR_2: | |
3043 | case BUILT_IN_ATOMIC_FETCH_OR_4: | |
3044 | case BUILT_IN_ATOMIC_FETCH_OR_8: | |
3045 | case BUILT_IN_ATOMIC_FETCH_OR_16: | |
3046 | optimize_atomic_bit_test_and (&i, | |
3047 | IFN_ATOMIC_BIT_TEST_AND_SET, | |
3048 | true, false); | |
3049 | break; | |
3050 | case BUILT_IN_SYNC_FETCH_AND_OR_1: | |
3051 | case BUILT_IN_SYNC_FETCH_AND_OR_2: | |
3052 | case BUILT_IN_SYNC_FETCH_AND_OR_4: | |
3053 | case BUILT_IN_SYNC_FETCH_AND_OR_8: | |
3054 | case BUILT_IN_SYNC_FETCH_AND_OR_16: | |
3055 | optimize_atomic_bit_test_and (&i, | |
3056 | IFN_ATOMIC_BIT_TEST_AND_SET, | |
3057 | false, false); | |
3058 | break; | |
3059 | ||
3060 | case BUILT_IN_ATOMIC_FETCH_XOR_1: | |
3061 | case BUILT_IN_ATOMIC_FETCH_XOR_2: | |
3062 | case BUILT_IN_ATOMIC_FETCH_XOR_4: | |
3063 | case BUILT_IN_ATOMIC_FETCH_XOR_8: | |
3064 | case BUILT_IN_ATOMIC_FETCH_XOR_16: | |
3065 | optimize_atomic_bit_test_and | |
3066 | (&i, IFN_ATOMIC_BIT_TEST_AND_COMPLEMENT, true, false); | |
3067 | break; | |
3068 | case BUILT_IN_SYNC_FETCH_AND_XOR_1: | |
3069 | case BUILT_IN_SYNC_FETCH_AND_XOR_2: | |
3070 | case BUILT_IN_SYNC_FETCH_AND_XOR_4: | |
3071 | case BUILT_IN_SYNC_FETCH_AND_XOR_8: | |
3072 | case BUILT_IN_SYNC_FETCH_AND_XOR_16: | |
3073 | optimize_atomic_bit_test_and | |
3074 | (&i, IFN_ATOMIC_BIT_TEST_AND_COMPLEMENT, false, false); | |
3075 | break; | |
3076 | ||
3077 | case BUILT_IN_ATOMIC_XOR_FETCH_1: | |
3078 | case BUILT_IN_ATOMIC_XOR_FETCH_2: | |
3079 | case BUILT_IN_ATOMIC_XOR_FETCH_4: | |
3080 | case BUILT_IN_ATOMIC_XOR_FETCH_8: | |
3081 | case BUILT_IN_ATOMIC_XOR_FETCH_16: | |
3082 | optimize_atomic_bit_test_and | |
3083 | (&i, IFN_ATOMIC_BIT_TEST_AND_COMPLEMENT, true, true); | |
3084 | break; | |
3085 | case BUILT_IN_SYNC_XOR_AND_FETCH_1: | |
3086 | case BUILT_IN_SYNC_XOR_AND_FETCH_2: | |
3087 | case BUILT_IN_SYNC_XOR_AND_FETCH_4: | |
3088 | case BUILT_IN_SYNC_XOR_AND_FETCH_8: | |
3089 | case BUILT_IN_SYNC_XOR_AND_FETCH_16: | |
3090 | optimize_atomic_bit_test_and | |
3091 | (&i, IFN_ATOMIC_BIT_TEST_AND_COMPLEMENT, false, true); | |
3092 | break; | |
3093 | ||
3094 | case BUILT_IN_ATOMIC_FETCH_AND_1: | |
3095 | case BUILT_IN_ATOMIC_FETCH_AND_2: | |
3096 | case BUILT_IN_ATOMIC_FETCH_AND_4: | |
3097 | case BUILT_IN_ATOMIC_FETCH_AND_8: | |
3098 | case BUILT_IN_ATOMIC_FETCH_AND_16: | |
3099 | optimize_atomic_bit_test_and (&i, | |
3100 | IFN_ATOMIC_BIT_TEST_AND_RESET, | |
3101 | true, false); | |
3102 | break; | |
3103 | case BUILT_IN_SYNC_FETCH_AND_AND_1: | |
3104 | case BUILT_IN_SYNC_FETCH_AND_AND_2: | |
3105 | case BUILT_IN_SYNC_FETCH_AND_AND_4: | |
3106 | case BUILT_IN_SYNC_FETCH_AND_AND_8: | |
3107 | case BUILT_IN_SYNC_FETCH_AND_AND_16: | |
3108 | optimize_atomic_bit_test_and (&i, | |
3109 | IFN_ATOMIC_BIT_TEST_AND_RESET, | |
3110 | false, false); | |
3111 | break; | |
3112 | ||
40a3eb84 | 3113 | case BUILT_IN_VA_START: |
3114 | case BUILT_IN_VA_END: | |
3115 | case BUILT_IN_VA_COPY: | |
3116 | /* These shouldn't be folded before pass_stdarg. */ | |
3117 | result = optimize_stdarg_builtin (stmt); | |
3118 | if (result) | |
3119 | break; | |
3120 | /* FALLTHRU */ | |
f87df69a | 3121 | |
40a3eb84 | 3122 | default:; |
3123 | } | |
bdd0e199 | 3124 | |
40a3eb84 | 3125 | if (!result) |
3126 | { | |
3127 | gsi_next (&i); | |
3128 | continue; | |
3129 | } | |
4ee9c684 | 3130 | |
40a3eb84 | 3131 | if (!update_call_from_tree (&i, result)) |
3132 | gimplify_and_update_call_from_tree (&i, result); | |
3133 | } | |
3134 | ||
3135 | todoflags |= TODO_update_address_taken; | |
f87df69a | 3136 | |
4ee9c684 | 3137 | if (dump_file && (dump_flags & TDF_DETAILS)) |
3138 | { | |
3139 | fprintf (dump_file, "Simplified\n "); | |
75a70cf9 | 3140 | print_gimple_stmt (dump_file, stmt, 0, dump_flags); |
4ee9c684 | 3141 | } |
3142 | ||
75a70cf9 | 3143 | old_stmt = stmt; |
75a70cf9 | 3144 | stmt = gsi_stmt (i); |
4c5fd53c | 3145 | update_stmt (stmt); |
de6ed584 | 3146 | |
75a70cf9 | 3147 | if (maybe_clean_or_replace_eh_stmt (old_stmt, stmt) |
3148 | && gimple_purge_dead_eh_edges (bb)) | |
b36237eb | 3149 | cfg_changed = true; |
4ee9c684 | 3150 | |
3151 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
3152 | { | |
3153 | fprintf (dump_file, "to\n "); | |
75a70cf9 | 3154 | print_gimple_stmt (dump_file, stmt, 0, dump_flags); |
4ee9c684 | 3155 | fprintf (dump_file, "\n"); |
3156 | } | |
0a39fd54 | 3157 | |
3158 | /* Retry the same statement if it changed into another | |
3159 | builtin, there might be new opportunities now. */ | |
75a70cf9 | 3160 | if (gimple_code (stmt) != GIMPLE_CALL) |
0a39fd54 | 3161 | { |
75a70cf9 | 3162 | gsi_next (&i); |
0a39fd54 | 3163 | continue; |
3164 | } | |
75a70cf9 | 3165 | callee = gimple_call_fndecl (stmt); |
0a39fd54 | 3166 | if (!callee |
75a70cf9 | 3167 | || DECL_BUILT_IN_CLASS (callee) != BUILT_IN_NORMAL |
0a39fd54 | 3168 | || DECL_FUNCTION_CODE (callee) == fcode) |
75a70cf9 | 3169 | gsi_next (&i); |
4ee9c684 | 3170 | } |
3171 | } | |
48e1416a | 3172 | |
b36237eb | 3173 | /* Delete unreachable blocks. */ |
b1b7c0c4 | 3174 | if (cfg_changed) |
3175 | todoflags |= TODO_cleanup_cfg; | |
48e1416a | 3176 | |
b1b7c0c4 | 3177 | return todoflags; |
4ee9c684 | 3178 | } |
3179 | ||
cbe8bda8 | 3180 | } // anon namespace |
3181 | ||
3182 | gimple_opt_pass * | |
3183 | make_pass_fold_builtins (gcc::context *ctxt) | |
3184 | { | |
3185 | return new pass_fold_builtins (ctxt); | |
3186 | } |