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4ee9c684 | 1 | /* Conditional constant propagation pass for the GNU compiler. |
87c0a9fc | 2 | Copyright (C) 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009, |
3 | 2010 Free Software Foundation, Inc. | |
4ee9c684 | 4 | Adapted from original RTL SSA-CCP by Daniel Berlin <dberlin@dberlin.org> |
5 | Adapted to GIMPLE trees by Diego Novillo <dnovillo@redhat.com> | |
6 | ||
7 | This file is part of GCC. | |
48e1416a | 8 | |
4ee9c684 | 9 | GCC is free software; you can redistribute it and/or modify it |
10 | under the terms of the GNU General Public License as published by the | |
8c4c00c1 | 11 | Free Software Foundation; either version 3, or (at your option) any |
4ee9c684 | 12 | later version. |
48e1416a | 13 | |
4ee9c684 | 14 | GCC is distributed in the hope that it will be useful, but WITHOUT |
15 | ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or | |
16 | FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License | |
17 | for more details. | |
48e1416a | 18 | |
4ee9c684 | 19 | You should have received a copy of the GNU General Public License |
8c4c00c1 | 20 | along with GCC; see the file COPYING3. If not see |
21 | <http://www.gnu.org/licenses/>. */ | |
4ee9c684 | 22 | |
88dbf20f | 23 | /* Conditional constant propagation (CCP) is based on the SSA |
24 | propagation engine (tree-ssa-propagate.c). Constant assignments of | |
25 | the form VAR = CST are propagated from the assignments into uses of | |
26 | VAR, which in turn may generate new constants. The simulation uses | |
27 | a four level lattice to keep track of constant values associated | |
28 | with SSA names. Given an SSA name V_i, it may take one of the | |
29 | following values: | |
30 | ||
bfa30570 | 31 | UNINITIALIZED -> the initial state of the value. This value |
32 | is replaced with a correct initial value | |
33 | the first time the value is used, so the | |
34 | rest of the pass does not need to care about | |
35 | it. Using this value simplifies initialization | |
36 | of the pass, and prevents us from needlessly | |
37 | scanning statements that are never reached. | |
88dbf20f | 38 | |
39 | UNDEFINED -> V_i is a local variable whose definition | |
40 | has not been processed yet. Therefore we | |
41 | don't yet know if its value is a constant | |
42 | or not. | |
43 | ||
44 | CONSTANT -> V_i has been found to hold a constant | |
45 | value C. | |
46 | ||
47 | VARYING -> V_i cannot take a constant value, or if it | |
48 | does, it is not possible to determine it | |
49 | at compile time. | |
50 | ||
51 | The core of SSA-CCP is in ccp_visit_stmt and ccp_visit_phi_node: | |
52 | ||
53 | 1- In ccp_visit_stmt, we are interested in assignments whose RHS | |
54 | evaluates into a constant and conditional jumps whose predicate | |
55 | evaluates into a boolean true or false. When an assignment of | |
56 | the form V_i = CONST is found, V_i's lattice value is set to | |
57 | CONSTANT and CONST is associated with it. This causes the | |
58 | propagation engine to add all the SSA edges coming out the | |
59 | assignment into the worklists, so that statements that use V_i | |
60 | can be visited. | |
61 | ||
62 | If the statement is a conditional with a constant predicate, we | |
63 | mark the outgoing edges as executable or not executable | |
64 | depending on the predicate's value. This is then used when | |
65 | visiting PHI nodes to know when a PHI argument can be ignored. | |
48e1416a | 66 | |
88dbf20f | 67 | |
68 | 2- In ccp_visit_phi_node, if all the PHI arguments evaluate to the | |
69 | same constant C, then the LHS of the PHI is set to C. This | |
70 | evaluation is known as the "meet operation". Since one of the | |
71 | goals of this evaluation is to optimistically return constant | |
72 | values as often as possible, it uses two main short cuts: | |
73 | ||
74 | - If an argument is flowing in through a non-executable edge, it | |
75 | is ignored. This is useful in cases like this: | |
76 | ||
77 | if (PRED) | |
78 | a_9 = 3; | |
79 | else | |
80 | a_10 = 100; | |
81 | a_11 = PHI (a_9, a_10) | |
82 | ||
83 | If PRED is known to always evaluate to false, then we can | |
84 | assume that a_11 will always take its value from a_10, meaning | |
85 | that instead of consider it VARYING (a_9 and a_10 have | |
86 | different values), we can consider it CONSTANT 100. | |
87 | ||
88 | - If an argument has an UNDEFINED value, then it does not affect | |
89 | the outcome of the meet operation. If a variable V_i has an | |
90 | UNDEFINED value, it means that either its defining statement | |
91 | hasn't been visited yet or V_i has no defining statement, in | |
92 | which case the original symbol 'V' is being used | |
93 | uninitialized. Since 'V' is a local variable, the compiler | |
94 | may assume any initial value for it. | |
95 | ||
96 | ||
97 | After propagation, every variable V_i that ends up with a lattice | |
98 | value of CONSTANT will have the associated constant value in the | |
99 | array CONST_VAL[i].VALUE. That is fed into substitute_and_fold for | |
100 | final substitution and folding. | |
101 | ||
102 | ||
103 | Constant propagation in stores and loads (STORE-CCP) | |
104 | ---------------------------------------------------- | |
105 | ||
106 | While CCP has all the logic to propagate constants in GIMPLE | |
107 | registers, it is missing the ability to associate constants with | |
108 | stores and loads (i.e., pointer dereferences, structures and | |
109 | global/aliased variables). We don't keep loads and stores in | |
110 | SSA, but we do build a factored use-def web for them (in the | |
111 | virtual operands). | |
112 | ||
113 | For instance, consider the following code fragment: | |
114 | ||
115 | struct A a; | |
116 | const int B = 42; | |
117 | ||
118 | void foo (int i) | |
119 | { | |
120 | if (i > 10) | |
121 | a.a = 42; | |
122 | else | |
123 | { | |
124 | a.b = 21; | |
125 | a.a = a.b + 21; | |
126 | } | |
127 | ||
128 | if (a.a != B) | |
129 | never_executed (); | |
130 | } | |
131 | ||
132 | We should be able to deduce that the predicate 'a.a != B' is always | |
133 | false. To achieve this, we associate constant values to the SSA | |
4fb5e5ca | 134 | names in the VDEF operands for each store. Additionally, |
135 | since we also glob partial loads/stores with the base symbol, we | |
136 | also keep track of the memory reference where the constant value | |
137 | was stored (in the MEM_REF field of PROP_VALUE_T). For instance, | |
88dbf20f | 138 | |
4fb5e5ca | 139 | # a_5 = VDEF <a_4> |
88dbf20f | 140 | a.a = 2; |
141 | ||
142 | # VUSE <a_5> | |
143 | x_3 = a.b; | |
144 | ||
145 | In the example above, CCP will associate value '2' with 'a_5', but | |
146 | it would be wrong to replace the load from 'a.b' with '2', because | |
147 | '2' had been stored into a.a. | |
148 | ||
bfa30570 | 149 | Note that the initial value of virtual operands is VARYING, not |
150 | UNDEFINED. Consider, for instance global variables: | |
88dbf20f | 151 | |
152 | int A; | |
153 | ||
154 | foo (int i) | |
155 | { | |
156 | if (i_3 > 10) | |
157 | A_4 = 3; | |
158 | # A_5 = PHI (A_4, A_2); | |
159 | ||
160 | # VUSE <A_5> | |
161 | A.0_6 = A; | |
162 | ||
163 | return A.0_6; | |
164 | } | |
165 | ||
166 | The value of A_2 cannot be assumed to be UNDEFINED, as it may have | |
167 | been defined outside of foo. If we were to assume it UNDEFINED, we | |
bfa30570 | 168 | would erroneously optimize the above into 'return 3;'. |
88dbf20f | 169 | |
170 | Though STORE-CCP is not too expensive, it does have to do more work | |
171 | than regular CCP, so it is only enabled at -O2. Both regular CCP | |
172 | and STORE-CCP use the exact same algorithm. The only distinction | |
173 | is that when doing STORE-CCP, the boolean variable DO_STORE_CCP is | |
174 | set to true. This affects the evaluation of statements and PHI | |
175 | nodes. | |
4ee9c684 | 176 | |
177 | References: | |
178 | ||
179 | Constant propagation with conditional branches, | |
180 | Wegman and Zadeck, ACM TOPLAS 13(2):181-210. | |
181 | ||
182 | Building an Optimizing Compiler, | |
183 | Robert Morgan, Butterworth-Heinemann, 1998, Section 8.9. | |
184 | ||
185 | Advanced Compiler Design and Implementation, | |
186 | Steven Muchnick, Morgan Kaufmann, 1997, Section 12.6 */ | |
187 | ||
188 | #include "config.h" | |
189 | #include "system.h" | |
190 | #include "coretypes.h" | |
191 | #include "tm.h" | |
4ee9c684 | 192 | #include "tree.h" |
41511585 | 193 | #include "flags.h" |
4ee9c684 | 194 | #include "tm_p.h" |
4ee9c684 | 195 | #include "basic-block.h" |
41511585 | 196 | #include "output.h" |
41511585 | 197 | #include "function.h" |
ce084dfc | 198 | #include "tree-pretty-print.h" |
199 | #include "gimple-pretty-print.h" | |
41511585 | 200 | #include "timevar.h" |
4ee9c684 | 201 | #include "tree-dump.h" |
41511585 | 202 | #include "tree-flow.h" |
4ee9c684 | 203 | #include "tree-pass.h" |
41511585 | 204 | #include "tree-ssa-propagate.h" |
5a4b7e1e | 205 | #include "value-prof.h" |
41511585 | 206 | #include "langhooks.h" |
8782adcf | 207 | #include "target.h" |
add6ee5e | 208 | #include "toplev.h" |
43fb76c1 | 209 | #include "dbgcnt.h" |
4ee9c684 | 210 | |
211 | ||
212 | /* Possible lattice values. */ | |
213 | typedef enum | |
214 | { | |
bfa30570 | 215 | UNINITIALIZED, |
4ee9c684 | 216 | UNDEFINED, |
217 | CONSTANT, | |
218 | VARYING | |
88dbf20f | 219 | } ccp_lattice_t; |
4ee9c684 | 220 | |
88dbf20f | 221 | /* Array of propagated constant values. After propagation, |
222 | CONST_VAL[I].VALUE holds the constant value for SSA_NAME(I). If | |
223 | the constant is held in an SSA name representing a memory store | |
4fb5e5ca | 224 | (i.e., a VDEF), CONST_VAL[I].MEM_REF will contain the actual |
225 | memory reference used to store (i.e., the LHS of the assignment | |
226 | doing the store). */ | |
20140406 | 227 | static prop_value_t *const_val; |
4ee9c684 | 228 | |
4af351a8 | 229 | static void canonicalize_float_value (prop_value_t *); |
6688f8ec | 230 | static bool ccp_fold_stmt (gimple_stmt_iterator *); |
4af351a8 | 231 | |
88dbf20f | 232 | /* Dump constant propagation value VAL to file OUTF prefixed by PREFIX. */ |
01406fc0 | 233 | |
234 | static void | |
88dbf20f | 235 | dump_lattice_value (FILE *outf, const char *prefix, prop_value_t val) |
01406fc0 | 236 | { |
41511585 | 237 | switch (val.lattice_val) |
01406fc0 | 238 | { |
88dbf20f | 239 | case UNINITIALIZED: |
240 | fprintf (outf, "%sUNINITIALIZED", prefix); | |
241 | break; | |
41511585 | 242 | case UNDEFINED: |
243 | fprintf (outf, "%sUNDEFINED", prefix); | |
244 | break; | |
245 | case VARYING: | |
246 | fprintf (outf, "%sVARYING", prefix); | |
247 | break; | |
41511585 | 248 | case CONSTANT: |
249 | fprintf (outf, "%sCONSTANT ", prefix); | |
88dbf20f | 250 | print_generic_expr (outf, val.value, dump_flags); |
41511585 | 251 | break; |
252 | default: | |
8c0963c4 | 253 | gcc_unreachable (); |
41511585 | 254 | } |
01406fc0 | 255 | } |
4ee9c684 | 256 | |
4ee9c684 | 257 | |
88dbf20f | 258 | /* Print lattice value VAL to stderr. */ |
259 | ||
260 | void debug_lattice_value (prop_value_t val); | |
261 | ||
4b987fac | 262 | DEBUG_FUNCTION void |
88dbf20f | 263 | debug_lattice_value (prop_value_t val) |
264 | { | |
265 | dump_lattice_value (stderr, "", val); | |
266 | fprintf (stderr, "\n"); | |
267 | } | |
4ee9c684 | 268 | |
4ee9c684 | 269 | |
88dbf20f | 270 | /* Compute a default value for variable VAR and store it in the |
271 | CONST_VAL array. The following rules are used to get default | |
272 | values: | |
01406fc0 | 273 | |
88dbf20f | 274 | 1- Global and static variables that are declared constant are |
275 | considered CONSTANT. | |
276 | ||
277 | 2- Any other value is considered UNDEFINED. This is useful when | |
41511585 | 278 | considering PHI nodes. PHI arguments that are undefined do not |
279 | change the constant value of the PHI node, which allows for more | |
88dbf20f | 280 | constants to be propagated. |
4ee9c684 | 281 | |
8883e700 | 282 | 3- Variables defined by statements other than assignments and PHI |
88dbf20f | 283 | nodes are considered VARYING. |
4ee9c684 | 284 | |
8883e700 | 285 | 4- Initial values of variables that are not GIMPLE registers are |
bfa30570 | 286 | considered VARYING. */ |
4ee9c684 | 287 | |
88dbf20f | 288 | static prop_value_t |
289 | get_default_value (tree var) | |
290 | { | |
291 | tree sym = SSA_NAME_VAR (var); | |
61207d43 | 292 | prop_value_t val = { UNINITIALIZED, NULL_TREE }; |
8edeb88b | 293 | gimple stmt; |
294 | ||
295 | stmt = SSA_NAME_DEF_STMT (var); | |
296 | ||
297 | if (gimple_nop_p (stmt)) | |
4ee9c684 | 298 | { |
8edeb88b | 299 | /* Variables defined by an empty statement are those used |
300 | before being initialized. If VAR is a local variable, we | |
301 | can assume initially that it is UNDEFINED, otherwise we must | |
302 | consider it VARYING. */ | |
303 | if (is_gimple_reg (sym) && TREE_CODE (sym) != PARM_DECL) | |
304 | val.lattice_val = UNDEFINED; | |
305 | else | |
306 | val.lattice_val = VARYING; | |
4ee9c684 | 307 | } |
8edeb88b | 308 | else if (is_gimple_assign (stmt) |
309 | /* Value-returning GIMPLE_CALL statements assign to | |
310 | a variable, and are treated similarly to GIMPLE_ASSIGN. */ | |
311 | || (is_gimple_call (stmt) | |
312 | && gimple_call_lhs (stmt) != NULL_TREE) | |
313 | || gimple_code (stmt) == GIMPLE_PHI) | |
41511585 | 314 | { |
8edeb88b | 315 | tree cst; |
316 | if (gimple_assign_single_p (stmt) | |
317 | && DECL_P (gimple_assign_rhs1 (stmt)) | |
318 | && (cst = get_symbol_constant_value (gimple_assign_rhs1 (stmt)))) | |
88dbf20f | 319 | { |
8edeb88b | 320 | val.lattice_val = CONSTANT; |
321 | val.value = cst; | |
88dbf20f | 322 | } |
323 | else | |
8edeb88b | 324 | /* Any other variable defined by an assignment or a PHI node |
325 | is considered UNDEFINED. */ | |
326 | val.lattice_val = UNDEFINED; | |
327 | } | |
328 | else | |
329 | { | |
330 | /* Otherwise, VAR will never take on a constant value. */ | |
331 | val.lattice_val = VARYING; | |
41511585 | 332 | } |
4ee9c684 | 333 | |
41511585 | 334 | return val; |
335 | } | |
4ee9c684 | 336 | |
4ee9c684 | 337 | |
bfa30570 | 338 | /* Get the constant value associated with variable VAR. */ |
4ee9c684 | 339 | |
bfa30570 | 340 | static inline prop_value_t * |
341 | get_value (tree var) | |
88dbf20f | 342 | { |
e004838d | 343 | prop_value_t *val; |
bfa30570 | 344 | |
e004838d | 345 | if (const_val == NULL) |
346 | return NULL; | |
347 | ||
348 | val = &const_val[SSA_NAME_VERSION (var)]; | |
bfa30570 | 349 | if (val->lattice_val == UNINITIALIZED) |
4ee9c684 | 350 | *val = get_default_value (var); |
351 | ||
4af351a8 | 352 | canonicalize_float_value (val); |
353 | ||
4ee9c684 | 354 | return val; |
355 | } | |
356 | ||
bfa30570 | 357 | /* Sets the value associated with VAR to VARYING. */ |
358 | ||
359 | static inline void | |
360 | set_value_varying (tree var) | |
361 | { | |
362 | prop_value_t *val = &const_val[SSA_NAME_VERSION (var)]; | |
363 | ||
364 | val->lattice_val = VARYING; | |
365 | val->value = NULL_TREE; | |
bfa30570 | 366 | } |
4ee9c684 | 367 | |
b31eb493 | 368 | /* For float types, modify the value of VAL to make ccp work correctly |
369 | for non-standard values (-0, NaN): | |
370 | ||
371 | If HONOR_SIGNED_ZEROS is false, and VAL = -0, we canonicalize it to 0. | |
372 | If HONOR_NANS is false, and VAL is NaN, we canonicalize it to UNDEFINED. | |
373 | This is to fix the following problem (see PR 29921): Suppose we have | |
374 | ||
375 | x = 0.0 * y | |
376 | ||
377 | and we set value of y to NaN. This causes value of x to be set to NaN. | |
378 | When we later determine that y is in fact VARYING, fold uses the fact | |
379 | that HONOR_NANS is false, and we try to change the value of x to 0, | |
380 | causing an ICE. With HONOR_NANS being false, the real appearance of | |
381 | NaN would cause undefined behavior, though, so claiming that y (and x) | |
382 | are UNDEFINED initially is correct. */ | |
383 | ||
384 | static void | |
385 | canonicalize_float_value (prop_value_t *val) | |
386 | { | |
387 | enum machine_mode mode; | |
388 | tree type; | |
389 | REAL_VALUE_TYPE d; | |
390 | ||
391 | if (val->lattice_val != CONSTANT | |
392 | || TREE_CODE (val->value) != REAL_CST) | |
393 | return; | |
394 | ||
395 | d = TREE_REAL_CST (val->value); | |
396 | type = TREE_TYPE (val->value); | |
397 | mode = TYPE_MODE (type); | |
398 | ||
399 | if (!HONOR_SIGNED_ZEROS (mode) | |
400 | && REAL_VALUE_MINUS_ZERO (d)) | |
401 | { | |
402 | val->value = build_real (type, dconst0); | |
403 | return; | |
404 | } | |
405 | ||
406 | if (!HONOR_NANS (mode) | |
407 | && REAL_VALUE_ISNAN (d)) | |
408 | { | |
409 | val->lattice_val = UNDEFINED; | |
410 | val->value = NULL; | |
b31eb493 | 411 | return; |
412 | } | |
413 | } | |
414 | ||
88dbf20f | 415 | /* Set the value for variable VAR to NEW_VAL. Return true if the new |
416 | value is different from VAR's previous value. */ | |
4ee9c684 | 417 | |
41511585 | 418 | static bool |
88dbf20f | 419 | set_lattice_value (tree var, prop_value_t new_val) |
4ee9c684 | 420 | { |
bfa30570 | 421 | prop_value_t *old_val = get_value (var); |
88dbf20f | 422 | |
b31eb493 | 423 | canonicalize_float_value (&new_val); |
424 | ||
88dbf20f | 425 | /* Lattice transitions must always be monotonically increasing in |
bfa30570 | 426 | value. If *OLD_VAL and NEW_VAL are the same, return false to |
427 | inform the caller that this was a non-transition. */ | |
428 | ||
aecfc21d | 429 | gcc_assert (old_val->lattice_val < new_val.lattice_val |
88dbf20f | 430 | || (old_val->lattice_val == new_val.lattice_val |
aecfc21d | 431 | && ((!old_val->value && !new_val.value) |
61207d43 | 432 | || operand_equal_p (old_val->value, new_val.value, 0)))); |
88dbf20f | 433 | |
434 | if (old_val->lattice_val != new_val.lattice_val) | |
4ee9c684 | 435 | { |
41511585 | 436 | if (dump_file && (dump_flags & TDF_DETAILS)) |
437 | { | |
88dbf20f | 438 | dump_lattice_value (dump_file, "Lattice value changed to ", new_val); |
bfa30570 | 439 | fprintf (dump_file, ". Adding SSA edges to worklist.\n"); |
41511585 | 440 | } |
441 | ||
88dbf20f | 442 | *old_val = new_val; |
443 | ||
bfa30570 | 444 | gcc_assert (new_val.lattice_val != UNDEFINED); |
445 | return true; | |
4ee9c684 | 446 | } |
41511585 | 447 | |
448 | return false; | |
4ee9c684 | 449 | } |
450 | ||
451 | ||
88dbf20f | 452 | /* Return the likely CCP lattice value for STMT. |
4ee9c684 | 453 | |
41511585 | 454 | If STMT has no operands, then return CONSTANT. |
4ee9c684 | 455 | |
d61b9af3 | 456 | Else if undefinedness of operands of STMT cause its value to be |
457 | undefined, then return UNDEFINED. | |
4ee9c684 | 458 | |
41511585 | 459 | Else if any operands of STMT are constants, then return CONSTANT. |
4ee9c684 | 460 | |
41511585 | 461 | Else return VARYING. */ |
4ee9c684 | 462 | |
88dbf20f | 463 | static ccp_lattice_t |
75a70cf9 | 464 | likely_value (gimple stmt) |
41511585 | 465 | { |
d61b9af3 | 466 | bool has_constant_operand, has_undefined_operand, all_undefined_operands; |
41511585 | 467 | tree use; |
468 | ssa_op_iter iter; | |
8edeb88b | 469 | unsigned i; |
4ee9c684 | 470 | |
590c3166 | 471 | enum gimple_code code = gimple_code (stmt); |
75a70cf9 | 472 | |
473 | /* This function appears to be called only for assignments, calls, | |
474 | conditionals, and switches, due to the logic in visit_stmt. */ | |
475 | gcc_assert (code == GIMPLE_ASSIGN | |
476 | || code == GIMPLE_CALL | |
477 | || code == GIMPLE_COND | |
478 | || code == GIMPLE_SWITCH); | |
88dbf20f | 479 | |
480 | /* If the statement has volatile operands, it won't fold to a | |
481 | constant value. */ | |
75a70cf9 | 482 | if (gimple_has_volatile_ops (stmt)) |
88dbf20f | 483 | return VARYING; |
484 | ||
75a70cf9 | 485 | /* Arrive here for more complex cases. */ |
bfa30570 | 486 | has_constant_operand = false; |
d61b9af3 | 487 | has_undefined_operand = false; |
488 | all_undefined_operands = true; | |
8edeb88b | 489 | FOR_EACH_SSA_TREE_OPERAND (use, stmt, iter, SSA_OP_USE) |
41511585 | 490 | { |
bfa30570 | 491 | prop_value_t *val = get_value (use); |
41511585 | 492 | |
bfa30570 | 493 | if (val->lattice_val == UNDEFINED) |
d61b9af3 | 494 | has_undefined_operand = true; |
495 | else | |
496 | all_undefined_operands = false; | |
88dbf20f | 497 | |
41511585 | 498 | if (val->lattice_val == CONSTANT) |
bfa30570 | 499 | has_constant_operand = true; |
4ee9c684 | 500 | } |
41511585 | 501 | |
dd277d48 | 502 | /* There may be constants in regular rhs operands. For calls we |
503 | have to ignore lhs, fndecl and static chain, otherwise only | |
504 | the lhs. */ | |
505 | for (i = (is_gimple_call (stmt) ? 2 : 0) + gimple_has_lhs (stmt); | |
8edeb88b | 506 | i < gimple_num_ops (stmt); ++i) |
507 | { | |
508 | tree op = gimple_op (stmt, i); | |
509 | if (!op || TREE_CODE (op) == SSA_NAME) | |
510 | continue; | |
511 | if (is_gimple_min_invariant (op)) | |
512 | has_constant_operand = true; | |
513 | } | |
514 | ||
87c0a9fc | 515 | if (has_constant_operand) |
516 | all_undefined_operands = false; | |
517 | ||
d61b9af3 | 518 | /* If the operation combines operands like COMPLEX_EXPR make sure to |
519 | not mark the result UNDEFINED if only one part of the result is | |
520 | undefined. */ | |
75a70cf9 | 521 | if (has_undefined_operand && all_undefined_operands) |
d61b9af3 | 522 | return UNDEFINED; |
75a70cf9 | 523 | else if (code == GIMPLE_ASSIGN && has_undefined_operand) |
d61b9af3 | 524 | { |
75a70cf9 | 525 | switch (gimple_assign_rhs_code (stmt)) |
d61b9af3 | 526 | { |
527 | /* Unary operators are handled with all_undefined_operands. */ | |
528 | case PLUS_EXPR: | |
529 | case MINUS_EXPR: | |
d61b9af3 | 530 | case POINTER_PLUS_EXPR: |
d61b9af3 | 531 | /* Not MIN_EXPR, MAX_EXPR. One VARYING operand may be selected. |
532 | Not bitwise operators, one VARYING operand may specify the | |
533 | result completely. Not logical operators for the same reason. | |
05a936a0 | 534 | Not COMPLEX_EXPR as one VARYING operand makes the result partly |
535 | not UNDEFINED. Not *DIV_EXPR, comparisons and shifts because | |
536 | the undefined operand may be promoted. */ | |
d61b9af3 | 537 | return UNDEFINED; |
538 | ||
539 | default: | |
540 | ; | |
541 | } | |
542 | } | |
543 | /* If there was an UNDEFINED operand but the result may be not UNDEFINED | |
544 | fall back to VARYING even if there were CONSTANT operands. */ | |
545 | if (has_undefined_operand) | |
546 | return VARYING; | |
547 | ||
8edeb88b | 548 | /* We do not consider virtual operands here -- load from read-only |
549 | memory may have only VARYING virtual operands, but still be | |
550 | constant. */ | |
bfa30570 | 551 | if (has_constant_operand |
8edeb88b | 552 | || gimple_references_memory_p (stmt)) |
88dbf20f | 553 | return CONSTANT; |
554 | ||
bfa30570 | 555 | return VARYING; |
4ee9c684 | 556 | } |
557 | ||
bfa30570 | 558 | /* Returns true if STMT cannot be constant. */ |
559 | ||
560 | static bool | |
75a70cf9 | 561 | surely_varying_stmt_p (gimple stmt) |
bfa30570 | 562 | { |
563 | /* If the statement has operands that we cannot handle, it cannot be | |
564 | constant. */ | |
75a70cf9 | 565 | if (gimple_has_volatile_ops (stmt)) |
bfa30570 | 566 | return true; |
567 | ||
f257af64 | 568 | /* If it is a call and does not return a value or is not a |
569 | builtin and not an indirect call, it is varying. */ | |
75a70cf9 | 570 | if (is_gimple_call (stmt)) |
f257af64 | 571 | { |
572 | tree fndecl; | |
573 | if (!gimple_call_lhs (stmt) | |
574 | || ((fndecl = gimple_call_fndecl (stmt)) != NULL_TREE | |
5768aeb3 | 575 | && !DECL_BUILT_IN (fndecl))) |
f257af64 | 576 | return true; |
577 | } | |
bfa30570 | 578 | |
8edeb88b | 579 | /* Any other store operation is not interesting. */ |
dd277d48 | 580 | else if (gimple_vdef (stmt)) |
8edeb88b | 581 | return true; |
582 | ||
bfa30570 | 583 | /* Anything other than assignments and conditional jumps are not |
584 | interesting for CCP. */ | |
75a70cf9 | 585 | if (gimple_code (stmt) != GIMPLE_ASSIGN |
f257af64 | 586 | && gimple_code (stmt) != GIMPLE_COND |
587 | && gimple_code (stmt) != GIMPLE_SWITCH | |
588 | && gimple_code (stmt) != GIMPLE_CALL) | |
bfa30570 | 589 | return true; |
590 | ||
591 | return false; | |
592 | } | |
4ee9c684 | 593 | |
41511585 | 594 | /* Initialize local data structures for CCP. */ |
4ee9c684 | 595 | |
596 | static void | |
41511585 | 597 | ccp_initialize (void) |
4ee9c684 | 598 | { |
41511585 | 599 | basic_block bb; |
4ee9c684 | 600 | |
43959b95 | 601 | const_val = XCNEWVEC (prop_value_t, num_ssa_names); |
4ee9c684 | 602 | |
41511585 | 603 | /* Initialize simulation flags for PHI nodes and statements. */ |
604 | FOR_EACH_BB (bb) | |
4ee9c684 | 605 | { |
75a70cf9 | 606 | gimple_stmt_iterator i; |
4ee9c684 | 607 | |
75a70cf9 | 608 | for (i = gsi_start_bb (bb); !gsi_end_p (i); gsi_next (&i)) |
41511585 | 609 | { |
75a70cf9 | 610 | gimple stmt = gsi_stmt (i); |
2193544e | 611 | bool is_varying; |
612 | ||
613 | /* If the statement is a control insn, then we do not | |
614 | want to avoid simulating the statement once. Failure | |
615 | to do so means that those edges will never get added. */ | |
616 | if (stmt_ends_bb_p (stmt)) | |
617 | is_varying = false; | |
618 | else | |
619 | is_varying = surely_varying_stmt_p (stmt); | |
4ee9c684 | 620 | |
bfa30570 | 621 | if (is_varying) |
41511585 | 622 | { |
88dbf20f | 623 | tree def; |
624 | ssa_op_iter iter; | |
625 | ||
626 | /* If the statement will not produce a constant, mark | |
627 | all its outputs VARYING. */ | |
628 | FOR_EACH_SSA_TREE_OPERAND (def, stmt, iter, SSA_OP_ALL_DEFS) | |
8edeb88b | 629 | set_value_varying (def); |
41511585 | 630 | } |
75a70cf9 | 631 | prop_set_simulate_again (stmt, !is_varying); |
41511585 | 632 | } |
4ee9c684 | 633 | } |
634 | ||
75a70cf9 | 635 | /* Now process PHI nodes. We never clear the simulate_again flag on |
636 | phi nodes, since we do not know which edges are executable yet, | |
637 | except for phi nodes for virtual operands when we do not do store ccp. */ | |
41511585 | 638 | FOR_EACH_BB (bb) |
4ee9c684 | 639 | { |
75a70cf9 | 640 | gimple_stmt_iterator i; |
41511585 | 641 | |
75a70cf9 | 642 | for (i = gsi_start_phis (bb); !gsi_end_p (i); gsi_next (&i)) |
643 | { | |
644 | gimple phi = gsi_stmt (i); | |
645 | ||
61207d43 | 646 | if (!is_gimple_reg (gimple_phi_result (phi))) |
75a70cf9 | 647 | prop_set_simulate_again (phi, false); |
bfa30570 | 648 | else |
75a70cf9 | 649 | prop_set_simulate_again (phi, true); |
41511585 | 650 | } |
4ee9c684 | 651 | } |
41511585 | 652 | } |
4ee9c684 | 653 | |
43fb76c1 | 654 | /* Debug count support. Reset the values of ssa names |
655 | VARYING when the total number ssa names analyzed is | |
656 | beyond the debug count specified. */ | |
657 | ||
658 | static void | |
659 | do_dbg_cnt (void) | |
660 | { | |
661 | unsigned i; | |
662 | for (i = 0; i < num_ssa_names; i++) | |
663 | { | |
664 | if (!dbg_cnt (ccp)) | |
665 | { | |
666 | const_val[i].lattice_val = VARYING; | |
667 | const_val[i].value = NULL_TREE; | |
668 | } | |
669 | } | |
670 | } | |
671 | ||
4ee9c684 | 672 | |
88dbf20f | 673 | /* Do final substitution of propagated values, cleanup the flowgraph and |
48e1416a | 674 | free allocated storage. |
4ee9c684 | 675 | |
33a34f1e | 676 | Return TRUE when something was optimized. */ |
677 | ||
678 | static bool | |
88dbf20f | 679 | ccp_finalize (void) |
4ee9c684 | 680 | { |
43fb76c1 | 681 | bool something_changed; |
682 | ||
683 | do_dbg_cnt (); | |
88dbf20f | 684 | /* Perform substitutions based on the known constant values. */ |
6688f8ec | 685 | something_changed = substitute_and_fold (const_val, ccp_fold_stmt); |
4ee9c684 | 686 | |
88dbf20f | 687 | free (const_val); |
e004838d | 688 | const_val = NULL; |
33a34f1e | 689 | return something_changed;; |
4ee9c684 | 690 | } |
691 | ||
692 | ||
88dbf20f | 693 | /* Compute the meet operator between *VAL1 and *VAL2. Store the result |
694 | in VAL1. | |
695 | ||
696 | any M UNDEFINED = any | |
88dbf20f | 697 | any M VARYING = VARYING |
698 | Ci M Cj = Ci if (i == j) | |
699 | Ci M Cj = VARYING if (i != j) | |
bfa30570 | 700 | */ |
4ee9c684 | 701 | |
702 | static void | |
88dbf20f | 703 | ccp_lattice_meet (prop_value_t *val1, prop_value_t *val2) |
4ee9c684 | 704 | { |
88dbf20f | 705 | if (val1->lattice_val == UNDEFINED) |
4ee9c684 | 706 | { |
88dbf20f | 707 | /* UNDEFINED M any = any */ |
708 | *val1 = *val2; | |
41511585 | 709 | } |
88dbf20f | 710 | else if (val2->lattice_val == UNDEFINED) |
92481a4d | 711 | { |
88dbf20f | 712 | /* any M UNDEFINED = any |
713 | Nothing to do. VAL1 already contains the value we want. */ | |
714 | ; | |
92481a4d | 715 | } |
88dbf20f | 716 | else if (val1->lattice_val == VARYING |
717 | || val2->lattice_val == VARYING) | |
41511585 | 718 | { |
88dbf20f | 719 | /* any M VARYING = VARYING. */ |
720 | val1->lattice_val = VARYING; | |
721 | val1->value = NULL_TREE; | |
41511585 | 722 | } |
88dbf20f | 723 | else if (val1->lattice_val == CONSTANT |
724 | && val2->lattice_val == CONSTANT | |
61207d43 | 725 | && simple_cst_equal (val1->value, val2->value) == 1) |
41511585 | 726 | { |
88dbf20f | 727 | /* Ci M Cj = Ci if (i == j) |
728 | Ci M Cj = VARYING if (i != j) | |
729 | ||
730 | If these two values come from memory stores, make sure that | |
731 | they come from the same memory reference. */ | |
732 | val1->lattice_val = CONSTANT; | |
733 | val1->value = val1->value; | |
41511585 | 734 | } |
735 | else | |
736 | { | |
88dbf20f | 737 | /* Any other combination is VARYING. */ |
738 | val1->lattice_val = VARYING; | |
739 | val1->value = NULL_TREE; | |
41511585 | 740 | } |
4ee9c684 | 741 | } |
742 | ||
743 | ||
41511585 | 744 | /* Loop through the PHI_NODE's parameters for BLOCK and compare their |
745 | lattice values to determine PHI_NODE's lattice value. The value of a | |
88dbf20f | 746 | PHI node is determined calling ccp_lattice_meet with all the arguments |
41511585 | 747 | of the PHI node that are incoming via executable edges. */ |
4ee9c684 | 748 | |
41511585 | 749 | static enum ssa_prop_result |
75a70cf9 | 750 | ccp_visit_phi_node (gimple phi) |
4ee9c684 | 751 | { |
75a70cf9 | 752 | unsigned i; |
88dbf20f | 753 | prop_value_t *old_val, new_val; |
4ee9c684 | 754 | |
41511585 | 755 | if (dump_file && (dump_flags & TDF_DETAILS)) |
4ee9c684 | 756 | { |
41511585 | 757 | fprintf (dump_file, "\nVisiting PHI node: "); |
75a70cf9 | 758 | print_gimple_stmt (dump_file, phi, 0, dump_flags); |
4ee9c684 | 759 | } |
4ee9c684 | 760 | |
75a70cf9 | 761 | old_val = get_value (gimple_phi_result (phi)); |
41511585 | 762 | switch (old_val->lattice_val) |
763 | { | |
764 | case VARYING: | |
88dbf20f | 765 | return SSA_PROP_VARYING; |
4ee9c684 | 766 | |
41511585 | 767 | case CONSTANT: |
768 | new_val = *old_val; | |
769 | break; | |
4ee9c684 | 770 | |
41511585 | 771 | case UNDEFINED: |
41511585 | 772 | new_val.lattice_val = UNDEFINED; |
88dbf20f | 773 | new_val.value = NULL_TREE; |
41511585 | 774 | break; |
4ee9c684 | 775 | |
41511585 | 776 | default: |
8c0963c4 | 777 | gcc_unreachable (); |
41511585 | 778 | } |
4ee9c684 | 779 | |
75a70cf9 | 780 | for (i = 0; i < gimple_phi_num_args (phi); i++) |
41511585 | 781 | { |
88dbf20f | 782 | /* Compute the meet operator over all the PHI arguments flowing |
783 | through executable edges. */ | |
75a70cf9 | 784 | edge e = gimple_phi_arg_edge (phi, i); |
4ee9c684 | 785 | |
41511585 | 786 | if (dump_file && (dump_flags & TDF_DETAILS)) |
787 | { | |
788 | fprintf (dump_file, | |
789 | "\n Argument #%d (%d -> %d %sexecutable)\n", | |
790 | i, e->src->index, e->dest->index, | |
791 | (e->flags & EDGE_EXECUTABLE) ? "" : "not "); | |
792 | } | |
793 | ||
794 | /* If the incoming edge is executable, Compute the meet operator for | |
795 | the existing value of the PHI node and the current PHI argument. */ | |
796 | if (e->flags & EDGE_EXECUTABLE) | |
797 | { | |
75a70cf9 | 798 | tree arg = gimple_phi_arg (phi, i)->def; |
88dbf20f | 799 | prop_value_t arg_val; |
4ee9c684 | 800 | |
88dbf20f | 801 | if (is_gimple_min_invariant (arg)) |
41511585 | 802 | { |
88dbf20f | 803 | arg_val.lattice_val = CONSTANT; |
804 | arg_val.value = arg; | |
41511585 | 805 | } |
806 | else | |
bfa30570 | 807 | arg_val = *(get_value (arg)); |
4ee9c684 | 808 | |
88dbf20f | 809 | ccp_lattice_meet (&new_val, &arg_val); |
4ee9c684 | 810 | |
41511585 | 811 | if (dump_file && (dump_flags & TDF_DETAILS)) |
812 | { | |
813 | fprintf (dump_file, "\t"); | |
88dbf20f | 814 | print_generic_expr (dump_file, arg, dump_flags); |
815 | dump_lattice_value (dump_file, "\tValue: ", arg_val); | |
41511585 | 816 | fprintf (dump_file, "\n"); |
817 | } | |
4ee9c684 | 818 | |
41511585 | 819 | if (new_val.lattice_val == VARYING) |
820 | break; | |
821 | } | |
822 | } | |
4ee9c684 | 823 | |
824 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
41511585 | 825 | { |
826 | dump_lattice_value (dump_file, "\n PHI node value: ", new_val); | |
827 | fprintf (dump_file, "\n\n"); | |
828 | } | |
829 | ||
bfa30570 | 830 | /* Make the transition to the new value. */ |
75a70cf9 | 831 | if (set_lattice_value (gimple_phi_result (phi), new_val)) |
41511585 | 832 | { |
833 | if (new_val.lattice_val == VARYING) | |
834 | return SSA_PROP_VARYING; | |
835 | else | |
836 | return SSA_PROP_INTERESTING; | |
837 | } | |
838 | else | |
839 | return SSA_PROP_NOT_INTERESTING; | |
4ee9c684 | 840 | } |
841 | ||
41511585 | 842 | /* CCP specific front-end to the non-destructive constant folding |
843 | routines. | |
4ee9c684 | 844 | |
845 | Attempt to simplify the RHS of STMT knowing that one or more | |
846 | operands are constants. | |
847 | ||
848 | If simplification is possible, return the simplified RHS, | |
75a70cf9 | 849 | otherwise return the original RHS or NULL_TREE. */ |
4ee9c684 | 850 | |
851 | static tree | |
75a70cf9 | 852 | ccp_fold (gimple stmt) |
4ee9c684 | 853 | { |
389dd41b | 854 | location_t loc = gimple_location (stmt); |
75a70cf9 | 855 | switch (gimple_code (stmt)) |
88dbf20f | 856 | { |
75a70cf9 | 857 | case GIMPLE_ASSIGN: |
858 | { | |
859 | enum tree_code subcode = gimple_assign_rhs_code (stmt); | |
860 | ||
861 | switch (get_gimple_rhs_class (subcode)) | |
862 | { | |
863 | case GIMPLE_SINGLE_RHS: | |
864 | { | |
865 | tree rhs = gimple_assign_rhs1 (stmt); | |
866 | enum tree_code_class kind = TREE_CODE_CLASS (subcode); | |
867 | ||
868 | if (TREE_CODE (rhs) == SSA_NAME) | |
869 | { | |
870 | /* If the RHS is an SSA_NAME, return its known constant value, | |
871 | if any. */ | |
872 | return get_value (rhs)->value; | |
873 | } | |
874 | /* Handle propagating invariant addresses into address operations. | |
875 | The folding we do here matches that in tree-ssa-forwprop.c. */ | |
876 | else if (TREE_CODE (rhs) == ADDR_EXPR) | |
877 | { | |
878 | tree *base; | |
879 | base = &TREE_OPERAND (rhs, 0); | |
880 | while (handled_component_p (*base)) | |
881 | base = &TREE_OPERAND (*base, 0); | |
882 | if (TREE_CODE (*base) == INDIRECT_REF | |
883 | && TREE_CODE (TREE_OPERAND (*base, 0)) == SSA_NAME) | |
884 | { | |
885 | prop_value_t *val = get_value (TREE_OPERAND (*base, 0)); | |
886 | if (val->lattice_val == CONSTANT | |
887 | && TREE_CODE (val->value) == ADDR_EXPR | |
fb8ed03f | 888 | && may_propagate_address_into_dereference |
889 | (val->value, *base)) | |
75a70cf9 | 890 | { |
891 | /* We need to return a new tree, not modify the IL | |
892 | or share parts of it. So play some tricks to | |
893 | avoid manually building it. */ | |
894 | tree ret, save = *base; | |
895 | *base = TREE_OPERAND (val->value, 0); | |
896 | ret = unshare_expr (rhs); | |
897 | recompute_tree_invariant_for_addr_expr (ret); | |
898 | *base = save; | |
899 | return ret; | |
900 | } | |
901 | } | |
902 | } | |
388a0bc7 | 903 | else if (TREE_CODE (rhs) == CONSTRUCTOR |
904 | && TREE_CODE (TREE_TYPE (rhs)) == VECTOR_TYPE | |
905 | && (CONSTRUCTOR_NELTS (rhs) | |
906 | == TYPE_VECTOR_SUBPARTS (TREE_TYPE (rhs)))) | |
907 | { | |
908 | unsigned i; | |
909 | tree val, list; | |
910 | ||
911 | list = NULL_TREE; | |
912 | FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (rhs), i, val) | |
913 | { | |
914 | if (TREE_CODE (val) == SSA_NAME | |
915 | && get_value (val)->lattice_val == CONSTANT) | |
916 | val = get_value (val)->value; | |
917 | if (TREE_CODE (val) == INTEGER_CST | |
918 | || TREE_CODE (val) == REAL_CST | |
919 | || TREE_CODE (val) == FIXED_CST) | |
920 | list = tree_cons (NULL_TREE, val, list); | |
921 | else | |
922 | return NULL_TREE; | |
923 | } | |
924 | ||
925 | return build_vector (TREE_TYPE (rhs), nreverse (list)); | |
926 | } | |
4ee9c684 | 927 | |
75a70cf9 | 928 | if (kind == tcc_reference) |
3e4be816 | 929 | { |
0fefde02 | 930 | if ((TREE_CODE (rhs) == VIEW_CONVERT_EXPR |
931 | || TREE_CODE (rhs) == REALPART_EXPR | |
932 | || TREE_CODE (rhs) == IMAGPART_EXPR) | |
3e4be816 | 933 | && TREE_CODE (TREE_OPERAND (rhs, 0)) == SSA_NAME) |
934 | { | |
935 | prop_value_t *val = get_value (TREE_OPERAND (rhs, 0)); | |
936 | if (val->lattice_val == CONSTANT) | |
389dd41b | 937 | return fold_unary_loc (EXPR_LOCATION (rhs), |
938 | TREE_CODE (rhs), | |
3e4be816 | 939 | TREE_TYPE (rhs), val->value); |
940 | } | |
8edeb88b | 941 | else if (TREE_CODE (rhs) == INDIRECT_REF |
942 | && TREE_CODE (TREE_OPERAND (rhs, 0)) == SSA_NAME) | |
943 | { | |
944 | prop_value_t *val = get_value (TREE_OPERAND (rhs, 0)); | |
945 | if (val->lattice_val == CONSTANT | |
946 | && TREE_CODE (val->value) == ADDR_EXPR | |
947 | && useless_type_conversion_p (TREE_TYPE (rhs), | |
948 | TREE_TYPE (TREE_TYPE (val->value)))) | |
949 | rhs = TREE_OPERAND (val->value, 0); | |
950 | } | |
3e4be816 | 951 | return fold_const_aggregate_ref (rhs); |
952 | } | |
75a70cf9 | 953 | else if (kind == tcc_declaration) |
954 | return get_symbol_constant_value (rhs); | |
955 | return rhs; | |
956 | } | |
48e1416a | 957 | |
75a70cf9 | 958 | case GIMPLE_UNARY_RHS: |
959 | { | |
960 | /* Handle unary operators that can appear in GIMPLE form. | |
961 | Note that we know the single operand must be a constant, | |
962 | so this should almost always return a simplified RHS. */ | |
963 | tree lhs = gimple_assign_lhs (stmt); | |
964 | tree op0 = gimple_assign_rhs1 (stmt); | |
965 | ||
966 | /* Simplify the operand down to a constant. */ | |
967 | if (TREE_CODE (op0) == SSA_NAME) | |
968 | { | |
969 | prop_value_t *val = get_value (op0); | |
970 | if (val->lattice_val == CONSTANT) | |
971 | op0 = get_value (op0)->value; | |
972 | } | |
973 | ||
974 | /* Conversions are useless for CCP purposes if they are | |
975 | value-preserving. Thus the restrictions that | |
976 | useless_type_conversion_p places for pointer type conversions | |
977 | do not apply here. Substitution later will only substitute to | |
978 | allowed places. */ | |
d9659041 | 979 | if (CONVERT_EXPR_CODE_P (subcode) |
5768aeb3 | 980 | && POINTER_TYPE_P (TREE_TYPE (lhs)) |
981 | && POINTER_TYPE_P (TREE_TYPE (op0)) | |
982 | /* Do not allow differences in volatile qualification | |
983 | as this might get us confused as to whether a | |
984 | propagation destination statement is volatile | |
985 | or not. See PR36988. */ | |
986 | && (TYPE_VOLATILE (TREE_TYPE (TREE_TYPE (lhs))) | |
987 | == TYPE_VOLATILE (TREE_TYPE (TREE_TYPE (op0))))) | |
988 | { | |
989 | tree tem; | |
990 | /* Still try to generate a constant of correct type. */ | |
991 | if (!useless_type_conversion_p (TREE_TYPE (lhs), | |
992 | TREE_TYPE (op0)) | |
993 | && ((tem = maybe_fold_offset_to_address | |
389dd41b | 994 | (loc, |
e60a6f7b | 995 | op0, integer_zero_node, TREE_TYPE (lhs))) |
5768aeb3 | 996 | != NULL_TREE)) |
997 | return tem; | |
998 | return op0; | |
999 | } | |
75a70cf9 | 1000 | |
48e1416a | 1001 | return |
389dd41b | 1002 | fold_unary_ignore_overflow_loc (loc, subcode, |
1003 | gimple_expr_type (stmt), op0); | |
f1fb2997 | 1004 | } |
75a70cf9 | 1005 | |
1006 | case GIMPLE_BINARY_RHS: | |
1007 | { | |
1008 | /* Handle binary operators that can appear in GIMPLE form. */ | |
1009 | tree op0 = gimple_assign_rhs1 (stmt); | |
1010 | tree op1 = gimple_assign_rhs2 (stmt); | |
1011 | ||
1012 | /* Simplify the operands down to constants when appropriate. */ | |
1013 | if (TREE_CODE (op0) == SSA_NAME) | |
1014 | { | |
1015 | prop_value_t *val = get_value (op0); | |
1016 | if (val->lattice_val == CONSTANT) | |
1017 | op0 = val->value; | |
1018 | } | |
1019 | ||
1020 | if (TREE_CODE (op1) == SSA_NAME) | |
1021 | { | |
1022 | prop_value_t *val = get_value (op1); | |
1023 | if (val->lattice_val == CONSTANT) | |
1024 | op1 = val->value; | |
1025 | } | |
1026 | ||
5768aeb3 | 1027 | /* Fold &foo + CST into an invariant reference if possible. */ |
1028 | if (gimple_assign_rhs_code (stmt) == POINTER_PLUS_EXPR | |
1029 | && TREE_CODE (op0) == ADDR_EXPR | |
1030 | && TREE_CODE (op1) == INTEGER_CST) | |
1031 | { | |
e60a6f7b | 1032 | tree tem = maybe_fold_offset_to_address |
4c0d4e21 | 1033 | (loc, op0, op1, TREE_TYPE (op0)); |
5768aeb3 | 1034 | if (tem != NULL_TREE) |
1035 | return tem; | |
1036 | } | |
1037 | ||
389dd41b | 1038 | return fold_binary_loc (loc, subcode, |
1039 | gimple_expr_type (stmt), op0, op1); | |
75a70cf9 | 1040 | } |
1041 | ||
1042 | default: | |
1043 | gcc_unreachable (); | |
1044 | } | |
1045 | } | |
1046 | break; | |
4ee9c684 | 1047 | |
75a70cf9 | 1048 | case GIMPLE_CALL: |
f257af64 | 1049 | { |
1050 | tree fn = gimple_call_fn (stmt); | |
1051 | prop_value_t *val; | |
1052 | ||
1053 | if (TREE_CODE (fn) == SSA_NAME) | |
1054 | { | |
1055 | val = get_value (fn); | |
1056 | if (val->lattice_val == CONSTANT) | |
1057 | fn = val->value; | |
1058 | } | |
1059 | if (TREE_CODE (fn) == ADDR_EXPR | |
8ef4f124 | 1060 | && TREE_CODE (TREE_OPERAND (fn, 0)) == FUNCTION_DECL |
f257af64 | 1061 | && DECL_BUILT_IN (TREE_OPERAND (fn, 0))) |
1062 | { | |
1063 | tree *args = XALLOCAVEC (tree, gimple_call_num_args (stmt)); | |
1064 | tree call, retval; | |
1065 | unsigned i; | |
1066 | for (i = 0; i < gimple_call_num_args (stmt); ++i) | |
1067 | { | |
1068 | args[i] = gimple_call_arg (stmt, i); | |
1069 | if (TREE_CODE (args[i]) == SSA_NAME) | |
1070 | { | |
1071 | val = get_value (args[i]); | |
1072 | if (val->lattice_val == CONSTANT) | |
1073 | args[i] = val->value; | |
1074 | } | |
1075 | } | |
389dd41b | 1076 | call = build_call_array_loc (loc, |
1077 | gimple_call_return_type (stmt), | |
1078 | fn, gimple_call_num_args (stmt), args); | |
1079 | retval = fold_call_expr (EXPR_LOCATION (call), call, false); | |
f257af64 | 1080 | if (retval) |
1081 | /* fold_call_expr wraps the result inside a NOP_EXPR. */ | |
1082 | STRIP_NOPS (retval); | |
1083 | return retval; | |
1084 | } | |
1085 | return NULL_TREE; | |
1086 | } | |
4ee9c684 | 1087 | |
75a70cf9 | 1088 | case GIMPLE_COND: |
1089 | { | |
1090 | /* Handle comparison operators that can appear in GIMPLE form. */ | |
1091 | tree op0 = gimple_cond_lhs (stmt); | |
1092 | tree op1 = gimple_cond_rhs (stmt); | |
1093 | enum tree_code code = gimple_cond_code (stmt); | |
1094 | ||
1095 | /* Simplify the operands down to constants when appropriate. */ | |
1096 | if (TREE_CODE (op0) == SSA_NAME) | |
1097 | { | |
1098 | prop_value_t *val = get_value (op0); | |
1099 | if (val->lattice_val == CONSTANT) | |
1100 | op0 = val->value; | |
1101 | } | |
1102 | ||
1103 | if (TREE_CODE (op1) == SSA_NAME) | |
1104 | { | |
1105 | prop_value_t *val = get_value (op1); | |
1106 | if (val->lattice_val == CONSTANT) | |
1107 | op1 = val->value; | |
1108 | } | |
1109 | ||
389dd41b | 1110 | return fold_binary_loc (loc, code, boolean_type_node, op0, op1); |
75a70cf9 | 1111 | } |
4ee9c684 | 1112 | |
75a70cf9 | 1113 | case GIMPLE_SWITCH: |
1114 | { | |
1115 | tree rhs = gimple_switch_index (stmt); | |
04236c3a | 1116 | |
75a70cf9 | 1117 | if (TREE_CODE (rhs) == SSA_NAME) |
1118 | { | |
1119 | /* If the RHS is an SSA_NAME, return its known constant value, | |
1120 | if any. */ | |
1121 | return get_value (rhs)->value; | |
1122 | } | |
04236c3a | 1123 | |
75a70cf9 | 1124 | return rhs; |
1125 | } | |
912f109f | 1126 | |
75a70cf9 | 1127 | default: |
1128 | gcc_unreachable (); | |
4ee9c684 | 1129 | } |
4ee9c684 | 1130 | } |
1131 | ||
1132 | ||
8782adcf | 1133 | /* Return the tree representing the element referenced by T if T is an |
1134 | ARRAY_REF or COMPONENT_REF into constant aggregates. Return | |
1135 | NULL_TREE otherwise. */ | |
1136 | ||
e004838d | 1137 | tree |
8782adcf | 1138 | fold_const_aggregate_ref (tree t) |
1139 | { | |
1140 | prop_value_t *value; | |
c75b4594 | 1141 | tree base, ctor, idx, field; |
1142 | unsigned HOST_WIDE_INT cnt; | |
1143 | tree cfield, cval; | |
8782adcf | 1144 | |
8edeb88b | 1145 | if (TREE_CODE_CLASS (TREE_CODE (t)) == tcc_declaration) |
1146 | return get_symbol_constant_value (t); | |
1147 | ||
8782adcf | 1148 | switch (TREE_CODE (t)) |
1149 | { | |
1150 | case ARRAY_REF: | |
1151 | /* Get a CONSTRUCTOR. If BASE is a VAR_DECL, get its | |
1152 | DECL_INITIAL. If BASE is a nested reference into another | |
1153 | ARRAY_REF or COMPONENT_REF, make a recursive call to resolve | |
1154 | the inner reference. */ | |
1155 | base = TREE_OPERAND (t, 0); | |
1156 | switch (TREE_CODE (base)) | |
1157 | { | |
1158 | case VAR_DECL: | |
1159 | if (!TREE_READONLY (base) | |
1160 | || TREE_CODE (TREE_TYPE (base)) != ARRAY_TYPE | |
1161 | || !targetm.binds_local_p (base)) | |
1162 | return NULL_TREE; | |
1163 | ||
1164 | ctor = DECL_INITIAL (base); | |
1165 | break; | |
1166 | ||
1167 | case ARRAY_REF: | |
1168 | case COMPONENT_REF: | |
1169 | ctor = fold_const_aggregate_ref (base); | |
1170 | break; | |
1171 | ||
04236c3a | 1172 | case STRING_CST: |
1173 | case CONSTRUCTOR: | |
1174 | ctor = base; | |
1175 | break; | |
1176 | ||
8782adcf | 1177 | default: |
1178 | return NULL_TREE; | |
1179 | } | |
1180 | ||
1181 | if (ctor == NULL_TREE | |
4f61cce6 | 1182 | || (TREE_CODE (ctor) != CONSTRUCTOR |
1183 | && TREE_CODE (ctor) != STRING_CST) | |
8782adcf | 1184 | || !TREE_STATIC (ctor)) |
1185 | return NULL_TREE; | |
1186 | ||
1187 | /* Get the index. If we have an SSA_NAME, try to resolve it | |
1188 | with the current lattice value for the SSA_NAME. */ | |
1189 | idx = TREE_OPERAND (t, 1); | |
1190 | switch (TREE_CODE (idx)) | |
1191 | { | |
1192 | case SSA_NAME: | |
bfa30570 | 1193 | if ((value = get_value (idx)) |
8782adcf | 1194 | && value->lattice_val == CONSTANT |
1195 | && TREE_CODE (value->value) == INTEGER_CST) | |
1196 | idx = value->value; | |
1197 | else | |
1198 | return NULL_TREE; | |
1199 | break; | |
1200 | ||
1201 | case INTEGER_CST: | |
1202 | break; | |
1203 | ||
1204 | default: | |
1205 | return NULL_TREE; | |
1206 | } | |
1207 | ||
4f61cce6 | 1208 | /* Fold read from constant string. */ |
1209 | if (TREE_CODE (ctor) == STRING_CST) | |
1210 | { | |
1211 | if ((TYPE_MODE (TREE_TYPE (t)) | |
1212 | == TYPE_MODE (TREE_TYPE (TREE_TYPE (ctor)))) | |
1213 | && (GET_MODE_CLASS (TYPE_MODE (TREE_TYPE (TREE_TYPE (ctor)))) | |
1214 | == MODE_INT) | |
1215 | && GET_MODE_SIZE (TYPE_MODE (TREE_TYPE (TREE_TYPE (ctor)))) == 1 | |
1216 | && compare_tree_int (idx, TREE_STRING_LENGTH (ctor)) < 0) | |
7b050b7b | 1217 | return build_int_cst_type (TREE_TYPE (t), |
1218 | (TREE_STRING_POINTER (ctor) | |
1219 | [TREE_INT_CST_LOW (idx)])); | |
4f61cce6 | 1220 | return NULL_TREE; |
1221 | } | |
1222 | ||
8782adcf | 1223 | /* Whoo-hoo! I'll fold ya baby. Yeah! */ |
c75b4594 | 1224 | FOR_EACH_CONSTRUCTOR_ELT (CONSTRUCTOR_ELTS (ctor), cnt, cfield, cval) |
1225 | if (tree_int_cst_equal (cfield, idx)) | |
590d65aa | 1226 | { |
6872bf3c | 1227 | STRIP_NOPS (cval); |
3a44a278 | 1228 | if (TREE_CODE (cval) == ADDR_EXPR) |
1229 | { | |
1230 | tree base = get_base_address (TREE_OPERAND (cval, 0)); | |
1231 | if (base && TREE_CODE (base) == VAR_DECL) | |
1232 | add_referenced_var (base); | |
1233 | } | |
590d65aa | 1234 | return cval; |
1235 | } | |
8782adcf | 1236 | break; |
1237 | ||
1238 | case COMPONENT_REF: | |
1239 | /* Get a CONSTRUCTOR. If BASE is a VAR_DECL, get its | |
1240 | DECL_INITIAL. If BASE is a nested reference into another | |
1241 | ARRAY_REF or COMPONENT_REF, make a recursive call to resolve | |
1242 | the inner reference. */ | |
1243 | base = TREE_OPERAND (t, 0); | |
1244 | switch (TREE_CODE (base)) | |
1245 | { | |
1246 | case VAR_DECL: | |
1247 | if (!TREE_READONLY (base) | |
1248 | || TREE_CODE (TREE_TYPE (base)) != RECORD_TYPE | |
1249 | || !targetm.binds_local_p (base)) | |
1250 | return NULL_TREE; | |
1251 | ||
1252 | ctor = DECL_INITIAL (base); | |
1253 | break; | |
1254 | ||
1255 | case ARRAY_REF: | |
1256 | case COMPONENT_REF: | |
1257 | ctor = fold_const_aggregate_ref (base); | |
1258 | break; | |
1259 | ||
1260 | default: | |
1261 | return NULL_TREE; | |
1262 | } | |
1263 | ||
1264 | if (ctor == NULL_TREE | |
1265 | || TREE_CODE (ctor) != CONSTRUCTOR | |
1266 | || !TREE_STATIC (ctor)) | |
1267 | return NULL_TREE; | |
1268 | ||
1269 | field = TREE_OPERAND (t, 1); | |
1270 | ||
c75b4594 | 1271 | FOR_EACH_CONSTRUCTOR_ELT (CONSTRUCTOR_ELTS (ctor), cnt, cfield, cval) |
1272 | if (cfield == field | |
8782adcf | 1273 | /* FIXME: Handle bit-fields. */ |
c75b4594 | 1274 | && ! DECL_BIT_FIELD (cfield)) |
590d65aa | 1275 | { |
6872bf3c | 1276 | STRIP_NOPS (cval); |
3a44a278 | 1277 | if (TREE_CODE (cval) == ADDR_EXPR) |
1278 | { | |
1279 | tree base = get_base_address (TREE_OPERAND (cval, 0)); | |
1280 | if (base && TREE_CODE (base) == VAR_DECL) | |
1281 | add_referenced_var (base); | |
1282 | } | |
590d65aa | 1283 | return cval; |
1284 | } | |
8782adcf | 1285 | break; |
1286 | ||
908cb59d | 1287 | case REALPART_EXPR: |
1288 | case IMAGPART_EXPR: | |
1289 | { | |
1290 | tree c = fold_const_aggregate_ref (TREE_OPERAND (t, 0)); | |
1291 | if (c && TREE_CODE (c) == COMPLEX_CST) | |
389dd41b | 1292 | return fold_build1_loc (EXPR_LOCATION (t), |
1293 | TREE_CODE (t), TREE_TYPE (t), c); | |
908cb59d | 1294 | break; |
1295 | } | |
04236c3a | 1296 | |
1297 | case INDIRECT_REF: | |
1298 | { | |
1299 | tree base = TREE_OPERAND (t, 0); | |
1300 | if (TREE_CODE (base) == SSA_NAME | |
1301 | && (value = get_value (base)) | |
1302 | && value->lattice_val == CONSTANT | |
65c463fd | 1303 | && TREE_CODE (value->value) == ADDR_EXPR |
1304 | && useless_type_conversion_p (TREE_TYPE (t), | |
1305 | TREE_TYPE (TREE_TYPE (value->value)))) | |
04236c3a | 1306 | return fold_const_aggregate_ref (TREE_OPERAND (value->value, 0)); |
1307 | break; | |
1308 | } | |
1309 | ||
8782adcf | 1310 | default: |
1311 | break; | |
1312 | } | |
1313 | ||
1314 | return NULL_TREE; | |
1315 | } | |
75a70cf9 | 1316 | |
1317 | /* Evaluate statement STMT. | |
1318 | Valid only for assignments, calls, conditionals, and switches. */ | |
4ee9c684 | 1319 | |
88dbf20f | 1320 | static prop_value_t |
75a70cf9 | 1321 | evaluate_stmt (gimple stmt) |
4ee9c684 | 1322 | { |
88dbf20f | 1323 | prop_value_t val; |
4f61cce6 | 1324 | tree simplified = NULL_TREE; |
88dbf20f | 1325 | ccp_lattice_t likelyvalue = likely_value (stmt); |
add6ee5e | 1326 | bool is_constant; |
88dbf20f | 1327 | |
add6ee5e | 1328 | fold_defer_overflow_warnings (); |
1329 | ||
4ee9c684 | 1330 | /* If the statement is likely to have a CONSTANT result, then try |
1331 | to fold the statement to determine the constant value. */ | |
75a70cf9 | 1332 | /* FIXME. This is the only place that we call ccp_fold. |
1333 | Since likely_value never returns CONSTANT for calls, we will | |
1334 | not attempt to fold them, including builtins that may profit. */ | |
4ee9c684 | 1335 | if (likelyvalue == CONSTANT) |
1336 | simplified = ccp_fold (stmt); | |
1337 | /* If the statement is likely to have a VARYING result, then do not | |
1338 | bother folding the statement. */ | |
04236c3a | 1339 | else if (likelyvalue == VARYING) |
75a70cf9 | 1340 | { |
590c3166 | 1341 | enum gimple_code code = gimple_code (stmt); |
75a70cf9 | 1342 | if (code == GIMPLE_ASSIGN) |
1343 | { | |
1344 | enum tree_code subcode = gimple_assign_rhs_code (stmt); | |
48e1416a | 1345 | |
75a70cf9 | 1346 | /* Other cases cannot satisfy is_gimple_min_invariant |
1347 | without folding. */ | |
1348 | if (get_gimple_rhs_class (subcode) == GIMPLE_SINGLE_RHS) | |
1349 | simplified = gimple_assign_rhs1 (stmt); | |
1350 | } | |
1351 | else if (code == GIMPLE_SWITCH) | |
1352 | simplified = gimple_switch_index (stmt); | |
1353 | else | |
a65c4d64 | 1354 | /* These cannot satisfy is_gimple_min_invariant without folding. */ |
1355 | gcc_assert (code == GIMPLE_CALL || code == GIMPLE_COND); | |
75a70cf9 | 1356 | } |
4ee9c684 | 1357 | |
add6ee5e | 1358 | is_constant = simplified && is_gimple_min_invariant (simplified); |
1359 | ||
1360 | fold_undefer_overflow_warnings (is_constant, stmt, 0); | |
1361 | ||
912f109f | 1362 | if (dump_file && (dump_flags & TDF_DETAILS)) |
1363 | { | |
1364 | fprintf (dump_file, "which is likely "); | |
1365 | switch (likelyvalue) | |
1366 | { | |
1367 | case CONSTANT: | |
1368 | fprintf (dump_file, "CONSTANT"); | |
1369 | break; | |
1370 | case UNDEFINED: | |
1371 | fprintf (dump_file, "UNDEFINED"); | |
1372 | break; | |
1373 | case VARYING: | |
1374 | fprintf (dump_file, "VARYING"); | |
1375 | break; | |
1376 | default:; | |
1377 | } | |
1378 | fprintf (dump_file, "\n"); | |
1379 | } | |
1380 | ||
add6ee5e | 1381 | if (is_constant) |
4ee9c684 | 1382 | { |
1383 | /* The statement produced a constant value. */ | |
1384 | val.lattice_val = CONSTANT; | |
88dbf20f | 1385 | val.value = simplified; |
4ee9c684 | 1386 | } |
1387 | else | |
1388 | { | |
1389 | /* The statement produced a nonconstant value. If the statement | |
88dbf20f | 1390 | had UNDEFINED operands, then the result of the statement |
1391 | should be UNDEFINED. Otherwise, the statement is VARYING. */ | |
bfa30570 | 1392 | if (likelyvalue == UNDEFINED) |
b765fa12 | 1393 | val.lattice_val = likelyvalue; |
1394 | else | |
1395 | val.lattice_val = VARYING; | |
1396 | ||
88dbf20f | 1397 | val.value = NULL_TREE; |
4ee9c684 | 1398 | } |
41511585 | 1399 | |
1400 | return val; | |
4ee9c684 | 1401 | } |
1402 | ||
6688f8ec | 1403 | /* Fold the stmt at *GSI with CCP specific information that propagating |
1404 | and regular folding does not catch. */ | |
1405 | ||
1406 | static bool | |
1407 | ccp_fold_stmt (gimple_stmt_iterator *gsi) | |
1408 | { | |
1409 | gimple stmt = gsi_stmt (*gsi); | |
6688f8ec | 1410 | |
94144e68 | 1411 | switch (gimple_code (stmt)) |
1412 | { | |
1413 | case GIMPLE_COND: | |
1414 | { | |
1415 | prop_value_t val; | |
1416 | /* Statement evaluation will handle type mismatches in constants | |
1417 | more gracefully than the final propagation. This allows us to | |
1418 | fold more conditionals here. */ | |
1419 | val = evaluate_stmt (stmt); | |
1420 | if (val.lattice_val != CONSTANT | |
1421 | || TREE_CODE (val.value) != INTEGER_CST) | |
1422 | return false; | |
1423 | ||
1424 | if (integer_zerop (val.value)) | |
1425 | gimple_cond_make_false (stmt); | |
1426 | else | |
1427 | gimple_cond_make_true (stmt); | |
6688f8ec | 1428 | |
94144e68 | 1429 | return true; |
1430 | } | |
6688f8ec | 1431 | |
94144e68 | 1432 | case GIMPLE_CALL: |
1433 | { | |
1434 | tree lhs = gimple_call_lhs (stmt); | |
1435 | prop_value_t *val; | |
1436 | tree argt; | |
1437 | bool changed = false; | |
1438 | unsigned i; | |
1439 | ||
1440 | /* If the call was folded into a constant make sure it goes | |
1441 | away even if we cannot propagate into all uses because of | |
1442 | type issues. */ | |
1443 | if (lhs | |
1444 | && TREE_CODE (lhs) == SSA_NAME | |
1445 | && (val = get_value (lhs)) | |
1446 | && val->lattice_val == CONSTANT) | |
1447 | { | |
338cce8f | 1448 | tree new_rhs = unshare_expr (val->value); |
1449 | bool res; | |
94144e68 | 1450 | if (!useless_type_conversion_p (TREE_TYPE (lhs), |
1451 | TREE_TYPE (new_rhs))) | |
1452 | new_rhs = fold_convert (TREE_TYPE (lhs), new_rhs); | |
338cce8f | 1453 | res = update_call_from_tree (gsi, new_rhs); |
1454 | gcc_assert (res); | |
94144e68 | 1455 | return true; |
1456 | } | |
1457 | ||
1458 | /* Propagate into the call arguments. Compared to replace_uses_in | |
1459 | this can use the argument slot types for type verification | |
1460 | instead of the current argument type. We also can safely | |
1461 | drop qualifiers here as we are dealing with constants anyway. */ | |
1462 | argt = TYPE_ARG_TYPES (TREE_TYPE (TREE_TYPE (gimple_call_fn (stmt)))); | |
1463 | for (i = 0; i < gimple_call_num_args (stmt) && argt; | |
1464 | ++i, argt = TREE_CHAIN (argt)) | |
1465 | { | |
1466 | tree arg = gimple_call_arg (stmt, i); | |
1467 | if (TREE_CODE (arg) == SSA_NAME | |
1468 | && (val = get_value (arg)) | |
1469 | && val->lattice_val == CONSTANT | |
1470 | && useless_type_conversion_p | |
1471 | (TYPE_MAIN_VARIANT (TREE_VALUE (argt)), | |
1472 | TYPE_MAIN_VARIANT (TREE_TYPE (val->value)))) | |
1473 | { | |
338cce8f | 1474 | gimple_call_set_arg (stmt, i, unshare_expr (val->value)); |
94144e68 | 1475 | changed = true; |
1476 | } | |
1477 | } | |
1478 | ||
1479 | return changed; | |
1480 | } | |
6688f8ec | 1481 | |
6872bf3c | 1482 | case GIMPLE_ASSIGN: |
1483 | { | |
1484 | tree lhs = gimple_assign_lhs (stmt); | |
1485 | prop_value_t *val; | |
1486 | ||
1487 | /* If we have a load that turned out to be constant replace it | |
1488 | as we cannot propagate into all uses in all cases. */ | |
1489 | if (gimple_assign_single_p (stmt) | |
1490 | && TREE_CODE (lhs) == SSA_NAME | |
1491 | && (val = get_value (lhs)) | |
1492 | && val->lattice_val == CONSTANT) | |
1493 | { | |
1494 | tree rhs = unshare_expr (val->value); | |
1495 | if (!useless_type_conversion_p (TREE_TYPE (lhs), TREE_TYPE (rhs))) | |
1496 | rhs = fold_convert (TREE_TYPE (lhs), rhs); | |
1497 | gimple_assign_set_rhs_from_tree (gsi, rhs); | |
1498 | return true; | |
1499 | } | |
1500 | ||
1501 | return false; | |
1502 | } | |
1503 | ||
94144e68 | 1504 | default: |
1505 | return false; | |
1506 | } | |
6688f8ec | 1507 | } |
1508 | ||
41511585 | 1509 | /* Visit the assignment statement STMT. Set the value of its LHS to the |
88dbf20f | 1510 | value computed by the RHS and store LHS in *OUTPUT_P. If STMT |
1511 | creates virtual definitions, set the value of each new name to that | |
75a70cf9 | 1512 | of the RHS (if we can derive a constant out of the RHS). |
1513 | Value-returning call statements also perform an assignment, and | |
1514 | are handled here. */ | |
4ee9c684 | 1515 | |
41511585 | 1516 | static enum ssa_prop_result |
75a70cf9 | 1517 | visit_assignment (gimple stmt, tree *output_p) |
4ee9c684 | 1518 | { |
88dbf20f | 1519 | prop_value_t val; |
88dbf20f | 1520 | enum ssa_prop_result retval; |
4ee9c684 | 1521 | |
75a70cf9 | 1522 | tree lhs = gimple_get_lhs (stmt); |
4ee9c684 | 1523 | |
75a70cf9 | 1524 | gcc_assert (gimple_code (stmt) != GIMPLE_CALL |
1525 | || gimple_call_lhs (stmt) != NULL_TREE); | |
1526 | ||
1527 | if (gimple_assign_copy_p (stmt)) | |
41511585 | 1528 | { |
75a70cf9 | 1529 | tree rhs = gimple_assign_rhs1 (stmt); |
88dbf20f | 1530 | |
75a70cf9 | 1531 | if (TREE_CODE (rhs) == SSA_NAME) |
1532 | { | |
1533 | /* For a simple copy operation, we copy the lattice values. */ | |
1534 | prop_value_t *nval = get_value (rhs); | |
1535 | val = *nval; | |
1536 | } | |
88dbf20f | 1537 | else |
75a70cf9 | 1538 | val = evaluate_stmt (stmt); |
41511585 | 1539 | } |
1540 | else | |
75a70cf9 | 1541 | /* Evaluate the statement, which could be |
1542 | either a GIMPLE_ASSIGN or a GIMPLE_CALL. */ | |
04236c3a | 1543 | val = evaluate_stmt (stmt); |
4ee9c684 | 1544 | |
88dbf20f | 1545 | retval = SSA_PROP_NOT_INTERESTING; |
4ee9c684 | 1546 | |
41511585 | 1547 | /* Set the lattice value of the statement's output. */ |
88dbf20f | 1548 | if (TREE_CODE (lhs) == SSA_NAME) |
4ee9c684 | 1549 | { |
88dbf20f | 1550 | /* If STMT is an assignment to an SSA_NAME, we only have one |
1551 | value to set. */ | |
1552 | if (set_lattice_value (lhs, val)) | |
1553 | { | |
1554 | *output_p = lhs; | |
1555 | if (val.lattice_val == VARYING) | |
1556 | retval = SSA_PROP_VARYING; | |
1557 | else | |
1558 | retval = SSA_PROP_INTERESTING; | |
1559 | } | |
4ee9c684 | 1560 | } |
88dbf20f | 1561 | |
1562 | return retval; | |
4ee9c684 | 1563 | } |
1564 | ||
4ee9c684 | 1565 | |
41511585 | 1566 | /* Visit the conditional statement STMT. Return SSA_PROP_INTERESTING |
1567 | if it can determine which edge will be taken. Otherwise, return | |
1568 | SSA_PROP_VARYING. */ | |
1569 | ||
1570 | static enum ssa_prop_result | |
75a70cf9 | 1571 | visit_cond_stmt (gimple stmt, edge *taken_edge_p) |
4ee9c684 | 1572 | { |
88dbf20f | 1573 | prop_value_t val; |
41511585 | 1574 | basic_block block; |
1575 | ||
75a70cf9 | 1576 | block = gimple_bb (stmt); |
41511585 | 1577 | val = evaluate_stmt (stmt); |
1578 | ||
1579 | /* Find which edge out of the conditional block will be taken and add it | |
1580 | to the worklist. If no single edge can be determined statically, | |
1581 | return SSA_PROP_VARYING to feed all the outgoing edges to the | |
1582 | propagation engine. */ | |
88dbf20f | 1583 | *taken_edge_p = val.value ? find_taken_edge (block, val.value) : 0; |
41511585 | 1584 | if (*taken_edge_p) |
1585 | return SSA_PROP_INTERESTING; | |
1586 | else | |
1587 | return SSA_PROP_VARYING; | |
4ee9c684 | 1588 | } |
1589 | ||
4ee9c684 | 1590 | |
41511585 | 1591 | /* Evaluate statement STMT. If the statement produces an output value and |
1592 | its evaluation changes the lattice value of its output, return | |
1593 | SSA_PROP_INTERESTING and set *OUTPUT_P to the SSA_NAME holding the | |
1594 | output value. | |
48e1416a | 1595 | |
41511585 | 1596 | If STMT is a conditional branch and we can determine its truth |
1597 | value, set *TAKEN_EDGE_P accordingly. If STMT produces a varying | |
1598 | value, return SSA_PROP_VARYING. */ | |
4ee9c684 | 1599 | |
41511585 | 1600 | static enum ssa_prop_result |
75a70cf9 | 1601 | ccp_visit_stmt (gimple stmt, edge *taken_edge_p, tree *output_p) |
41511585 | 1602 | { |
41511585 | 1603 | tree def; |
1604 | ssa_op_iter iter; | |
4ee9c684 | 1605 | |
41511585 | 1606 | if (dump_file && (dump_flags & TDF_DETAILS)) |
4ee9c684 | 1607 | { |
88dbf20f | 1608 | fprintf (dump_file, "\nVisiting statement:\n"); |
75a70cf9 | 1609 | print_gimple_stmt (dump_file, stmt, 0, dump_flags); |
4ee9c684 | 1610 | } |
4ee9c684 | 1611 | |
75a70cf9 | 1612 | switch (gimple_code (stmt)) |
4ee9c684 | 1613 | { |
75a70cf9 | 1614 | case GIMPLE_ASSIGN: |
1615 | /* If the statement is an assignment that produces a single | |
1616 | output value, evaluate its RHS to see if the lattice value of | |
1617 | its output has changed. */ | |
1618 | return visit_assignment (stmt, output_p); | |
1619 | ||
1620 | case GIMPLE_CALL: | |
1621 | /* A value-returning call also performs an assignment. */ | |
1622 | if (gimple_call_lhs (stmt) != NULL_TREE) | |
1623 | return visit_assignment (stmt, output_p); | |
1624 | break; | |
1625 | ||
1626 | case GIMPLE_COND: | |
1627 | case GIMPLE_SWITCH: | |
1628 | /* If STMT is a conditional branch, see if we can determine | |
1629 | which branch will be taken. */ | |
1630 | /* FIXME. It appears that we should be able to optimize | |
1631 | computed GOTOs here as well. */ | |
1632 | return visit_cond_stmt (stmt, taken_edge_p); | |
1633 | ||
1634 | default: | |
1635 | break; | |
4ee9c684 | 1636 | } |
4ee9c684 | 1637 | |
41511585 | 1638 | /* Any other kind of statement is not interesting for constant |
1639 | propagation and, therefore, not worth simulating. */ | |
41511585 | 1640 | if (dump_file && (dump_flags & TDF_DETAILS)) |
1641 | fprintf (dump_file, "No interesting values produced. Marked VARYING.\n"); | |
4ee9c684 | 1642 | |
41511585 | 1643 | /* Definitions made by statements other than assignments to |
1644 | SSA_NAMEs represent unknown modifications to their outputs. | |
1645 | Mark them VARYING. */ | |
88dbf20f | 1646 | FOR_EACH_SSA_TREE_OPERAND (def, stmt, iter, SSA_OP_ALL_DEFS) |
1647 | { | |
61207d43 | 1648 | prop_value_t v = { VARYING, NULL_TREE }; |
88dbf20f | 1649 | set_lattice_value (def, v); |
1650 | } | |
4ee9c684 | 1651 | |
41511585 | 1652 | return SSA_PROP_VARYING; |
1653 | } | |
4ee9c684 | 1654 | |
4ee9c684 | 1655 | |
88dbf20f | 1656 | /* Main entry point for SSA Conditional Constant Propagation. */ |
41511585 | 1657 | |
33a34f1e | 1658 | static unsigned int |
61207d43 | 1659 | do_ssa_ccp (void) |
41511585 | 1660 | { |
1661 | ccp_initialize (); | |
1662 | ssa_propagate (ccp_visit_stmt, ccp_visit_phi_node); | |
33a34f1e | 1663 | if (ccp_finalize ()) |
eb9161e7 | 1664 | return (TODO_cleanup_cfg | TODO_update_ssa | TODO_remove_unused_locals); |
33a34f1e | 1665 | else |
1666 | return 0; | |
4ee9c684 | 1667 | } |
1668 | ||
5664499b | 1669 | |
1670 | static bool | |
41511585 | 1671 | gate_ccp (void) |
5664499b | 1672 | { |
41511585 | 1673 | return flag_tree_ccp != 0; |
5664499b | 1674 | } |
1675 | ||
4ee9c684 | 1676 | |
48e1416a | 1677 | struct gimple_opt_pass pass_ccp = |
41511585 | 1678 | { |
20099e35 | 1679 | { |
1680 | GIMPLE_PASS, | |
41511585 | 1681 | "ccp", /* name */ |
1682 | gate_ccp, /* gate */ | |
88dbf20f | 1683 | do_ssa_ccp, /* execute */ |
41511585 | 1684 | NULL, /* sub */ |
1685 | NULL, /* next */ | |
1686 | 0, /* static_pass_number */ | |
1687 | TV_TREE_CCP, /* tv_id */ | |
49290934 | 1688 | PROP_cfg | PROP_ssa, /* properties_required */ |
41511585 | 1689 | 0, /* properties_provided */ |
b6246c40 | 1690 | 0, /* properties_destroyed */ |
41511585 | 1691 | 0, /* todo_flags_start */ |
33a34f1e | 1692 | TODO_dump_func | TODO_verify_ssa |
20099e35 | 1693 | | TODO_verify_stmts | TODO_ggc_collect/* todo_flags_finish */ |
1694 | } | |
41511585 | 1695 | }; |
4ee9c684 | 1696 | |
4ee9c684 | 1697 | |
75a70cf9 | 1698 | |
bdd0e199 | 1699 | /* Try to optimize out __builtin_stack_restore. Optimize it out |
1700 | if there is another __builtin_stack_restore in the same basic | |
1701 | block and no calls or ASM_EXPRs are in between, or if this block's | |
1702 | only outgoing edge is to EXIT_BLOCK and there are no calls or | |
1703 | ASM_EXPRs after this __builtin_stack_restore. */ | |
1704 | ||
1705 | static tree | |
75a70cf9 | 1706 | optimize_stack_restore (gimple_stmt_iterator i) |
bdd0e199 | 1707 | { |
6ea999da | 1708 | tree callee; |
1709 | gimple stmt; | |
75a70cf9 | 1710 | |
1711 | basic_block bb = gsi_bb (i); | |
1712 | gimple call = gsi_stmt (i); | |
bdd0e199 | 1713 | |
75a70cf9 | 1714 | if (gimple_code (call) != GIMPLE_CALL |
1715 | || gimple_call_num_args (call) != 1 | |
1716 | || TREE_CODE (gimple_call_arg (call, 0)) != SSA_NAME | |
1717 | || !POINTER_TYPE_P (TREE_TYPE (gimple_call_arg (call, 0)))) | |
bdd0e199 | 1718 | return NULL_TREE; |
1719 | ||
75a70cf9 | 1720 | for (gsi_next (&i); !gsi_end_p (i); gsi_next (&i)) |
bdd0e199 | 1721 | { |
75a70cf9 | 1722 | stmt = gsi_stmt (i); |
1723 | if (gimple_code (stmt) == GIMPLE_ASM) | |
bdd0e199 | 1724 | return NULL_TREE; |
75a70cf9 | 1725 | if (gimple_code (stmt) != GIMPLE_CALL) |
bdd0e199 | 1726 | continue; |
1727 | ||
75a70cf9 | 1728 | callee = gimple_call_fndecl (stmt); |
c40a6f90 | 1729 | if (!callee |
1730 | || DECL_BUILT_IN_CLASS (callee) != BUILT_IN_NORMAL | |
1731 | /* All regular builtins are ok, just obviously not alloca. */ | |
1732 | || DECL_FUNCTION_CODE (callee) == BUILT_IN_ALLOCA) | |
bdd0e199 | 1733 | return NULL_TREE; |
1734 | ||
1735 | if (DECL_FUNCTION_CODE (callee) == BUILT_IN_STACK_RESTORE) | |
6ea999da | 1736 | goto second_stack_restore; |
bdd0e199 | 1737 | } |
1738 | ||
6ea999da | 1739 | if (!gsi_end_p (i)) |
bdd0e199 | 1740 | return NULL_TREE; |
1741 | ||
6ea999da | 1742 | /* Allow one successor of the exit block, or zero successors. */ |
1743 | switch (EDGE_COUNT (bb->succs)) | |
1744 | { | |
1745 | case 0: | |
1746 | break; | |
1747 | case 1: | |
1748 | if (single_succ_edge (bb)->dest != EXIT_BLOCK_PTR) | |
1749 | return NULL_TREE; | |
1750 | break; | |
1751 | default: | |
1752 | return NULL_TREE; | |
1753 | } | |
1754 | second_stack_restore: | |
bdd0e199 | 1755 | |
6ea999da | 1756 | /* If there's exactly one use, then zap the call to __builtin_stack_save. |
1757 | If there are multiple uses, then the last one should remove the call. | |
1758 | In any case, whether the call to __builtin_stack_save can be removed | |
1759 | or not is irrelevant to removing the call to __builtin_stack_restore. */ | |
1760 | if (has_single_use (gimple_call_arg (call, 0))) | |
1761 | { | |
1762 | gimple stack_save = SSA_NAME_DEF_STMT (gimple_call_arg (call, 0)); | |
1763 | if (is_gimple_call (stack_save)) | |
1764 | { | |
1765 | callee = gimple_call_fndecl (stack_save); | |
1766 | if (callee | |
1767 | && DECL_BUILT_IN_CLASS (callee) == BUILT_IN_NORMAL | |
1768 | && DECL_FUNCTION_CODE (callee) == BUILT_IN_STACK_SAVE) | |
1769 | { | |
1770 | gimple_stmt_iterator stack_save_gsi; | |
1771 | tree rhs; | |
bdd0e199 | 1772 | |
6ea999da | 1773 | stack_save_gsi = gsi_for_stmt (stack_save); |
1774 | rhs = build_int_cst (TREE_TYPE (gimple_call_arg (call, 0)), 0); | |
1775 | update_call_from_tree (&stack_save_gsi, rhs); | |
1776 | } | |
1777 | } | |
1778 | } | |
bdd0e199 | 1779 | |
75a70cf9 | 1780 | /* No effect, so the statement will be deleted. */ |
bdd0e199 | 1781 | return integer_zero_node; |
1782 | } | |
75a70cf9 | 1783 | |
8a58ed0a | 1784 | /* If va_list type is a simple pointer and nothing special is needed, |
1785 | optimize __builtin_va_start (&ap, 0) into ap = __builtin_next_arg (0), | |
1786 | __builtin_va_end (&ap) out as NOP and __builtin_va_copy into a simple | |
1787 | pointer assignment. */ | |
1788 | ||
1789 | static tree | |
75a70cf9 | 1790 | optimize_stdarg_builtin (gimple call) |
8a58ed0a | 1791 | { |
5f57a8b1 | 1792 | tree callee, lhs, rhs, cfun_va_list; |
8a58ed0a | 1793 | bool va_list_simple_ptr; |
389dd41b | 1794 | location_t loc = gimple_location (call); |
8a58ed0a | 1795 | |
75a70cf9 | 1796 | if (gimple_code (call) != GIMPLE_CALL) |
8a58ed0a | 1797 | return NULL_TREE; |
1798 | ||
75a70cf9 | 1799 | callee = gimple_call_fndecl (call); |
5f57a8b1 | 1800 | |
1801 | cfun_va_list = targetm.fn_abi_va_list (callee); | |
1802 | va_list_simple_ptr = POINTER_TYPE_P (cfun_va_list) | |
1803 | && (TREE_TYPE (cfun_va_list) == void_type_node | |
1804 | || TREE_TYPE (cfun_va_list) == char_type_node); | |
1805 | ||
8a58ed0a | 1806 | switch (DECL_FUNCTION_CODE (callee)) |
1807 | { | |
1808 | case BUILT_IN_VA_START: | |
1809 | if (!va_list_simple_ptr | |
1810 | || targetm.expand_builtin_va_start != NULL | |
75a70cf9 | 1811 | || built_in_decls[BUILT_IN_NEXT_ARG] == NULL) |
8a58ed0a | 1812 | return NULL_TREE; |
1813 | ||
75a70cf9 | 1814 | if (gimple_call_num_args (call) != 2) |
8a58ed0a | 1815 | return NULL_TREE; |
1816 | ||
75a70cf9 | 1817 | lhs = gimple_call_arg (call, 0); |
8a58ed0a | 1818 | if (!POINTER_TYPE_P (TREE_TYPE (lhs)) |
1819 | || TYPE_MAIN_VARIANT (TREE_TYPE (TREE_TYPE (lhs))) | |
5f57a8b1 | 1820 | != TYPE_MAIN_VARIANT (cfun_va_list)) |
8a58ed0a | 1821 | return NULL_TREE; |
48e1416a | 1822 | |
389dd41b | 1823 | lhs = build_fold_indirect_ref_loc (loc, lhs); |
1824 | rhs = build_call_expr_loc (loc, built_in_decls[BUILT_IN_NEXT_ARG], | |
75a70cf9 | 1825 | 1, integer_zero_node); |
389dd41b | 1826 | rhs = fold_convert_loc (loc, TREE_TYPE (lhs), rhs); |
8a58ed0a | 1827 | return build2 (MODIFY_EXPR, TREE_TYPE (lhs), lhs, rhs); |
1828 | ||
1829 | case BUILT_IN_VA_COPY: | |
1830 | if (!va_list_simple_ptr) | |
1831 | return NULL_TREE; | |
1832 | ||
75a70cf9 | 1833 | if (gimple_call_num_args (call) != 2) |
8a58ed0a | 1834 | return NULL_TREE; |
1835 | ||
75a70cf9 | 1836 | lhs = gimple_call_arg (call, 0); |
8a58ed0a | 1837 | if (!POINTER_TYPE_P (TREE_TYPE (lhs)) |
1838 | || TYPE_MAIN_VARIANT (TREE_TYPE (TREE_TYPE (lhs))) | |
5f57a8b1 | 1839 | != TYPE_MAIN_VARIANT (cfun_va_list)) |
8a58ed0a | 1840 | return NULL_TREE; |
1841 | ||
389dd41b | 1842 | lhs = build_fold_indirect_ref_loc (loc, lhs); |
75a70cf9 | 1843 | rhs = gimple_call_arg (call, 1); |
8a58ed0a | 1844 | if (TYPE_MAIN_VARIANT (TREE_TYPE (rhs)) |
5f57a8b1 | 1845 | != TYPE_MAIN_VARIANT (cfun_va_list)) |
8a58ed0a | 1846 | return NULL_TREE; |
1847 | ||
389dd41b | 1848 | rhs = fold_convert_loc (loc, TREE_TYPE (lhs), rhs); |
8a58ed0a | 1849 | return build2 (MODIFY_EXPR, TREE_TYPE (lhs), lhs, rhs); |
1850 | ||
1851 | case BUILT_IN_VA_END: | |
75a70cf9 | 1852 | /* No effect, so the statement will be deleted. */ |
8a58ed0a | 1853 | return integer_zero_node; |
1854 | ||
1855 | default: | |
1856 | gcc_unreachable (); | |
1857 | } | |
1858 | } | |
75a70cf9 | 1859 | |
4ee9c684 | 1860 | /* A simple pass that attempts to fold all builtin functions. This pass |
1861 | is run after we've propagated as many constants as we can. */ | |
1862 | ||
2a1990e9 | 1863 | static unsigned int |
4ee9c684 | 1864 | execute_fold_all_builtins (void) |
1865 | { | |
b36237eb | 1866 | bool cfg_changed = false; |
4ee9c684 | 1867 | basic_block bb; |
b1b7c0c4 | 1868 | unsigned int todoflags = 0; |
48e1416a | 1869 | |
4ee9c684 | 1870 | FOR_EACH_BB (bb) |
1871 | { | |
75a70cf9 | 1872 | gimple_stmt_iterator i; |
1873 | for (i = gsi_start_bb (bb); !gsi_end_p (i); ) | |
4ee9c684 | 1874 | { |
75a70cf9 | 1875 | gimple stmt, old_stmt; |
4ee9c684 | 1876 | tree callee, result; |
0a39fd54 | 1877 | enum built_in_function fcode; |
4ee9c684 | 1878 | |
75a70cf9 | 1879 | stmt = gsi_stmt (i); |
1880 | ||
1881 | if (gimple_code (stmt) != GIMPLE_CALL) | |
0a39fd54 | 1882 | { |
75a70cf9 | 1883 | gsi_next (&i); |
0a39fd54 | 1884 | continue; |
1885 | } | |
75a70cf9 | 1886 | callee = gimple_call_fndecl (stmt); |
4ee9c684 | 1887 | if (!callee || DECL_BUILT_IN_CLASS (callee) != BUILT_IN_NORMAL) |
0a39fd54 | 1888 | { |
75a70cf9 | 1889 | gsi_next (&i); |
0a39fd54 | 1890 | continue; |
1891 | } | |
1892 | fcode = DECL_FUNCTION_CODE (callee); | |
4ee9c684 | 1893 | |
2d18b16d | 1894 | result = gimple_fold_builtin (stmt); |
5a4b7e1e | 1895 | |
1896 | if (result) | |
75a70cf9 | 1897 | gimple_remove_stmt_histograms (cfun, stmt); |
5a4b7e1e | 1898 | |
4ee9c684 | 1899 | if (!result) |
1900 | switch (DECL_FUNCTION_CODE (callee)) | |
1901 | { | |
1902 | case BUILT_IN_CONSTANT_P: | |
1903 | /* Resolve __builtin_constant_p. If it hasn't been | |
1904 | folded to integer_one_node by now, it's fairly | |
1905 | certain that the value simply isn't constant. */ | |
75a70cf9 | 1906 | result = integer_zero_node; |
4ee9c684 | 1907 | break; |
1908 | ||
bdd0e199 | 1909 | case BUILT_IN_STACK_RESTORE: |
75a70cf9 | 1910 | result = optimize_stack_restore (i); |
8a58ed0a | 1911 | if (result) |
1912 | break; | |
75a70cf9 | 1913 | gsi_next (&i); |
8a58ed0a | 1914 | continue; |
1915 | ||
1916 | case BUILT_IN_VA_START: | |
1917 | case BUILT_IN_VA_END: | |
1918 | case BUILT_IN_VA_COPY: | |
1919 | /* These shouldn't be folded before pass_stdarg. */ | |
75a70cf9 | 1920 | result = optimize_stdarg_builtin (stmt); |
bdd0e199 | 1921 | if (result) |
1922 | break; | |
1923 | /* FALLTHRU */ | |
1924 | ||
4ee9c684 | 1925 | default: |
75a70cf9 | 1926 | gsi_next (&i); |
4ee9c684 | 1927 | continue; |
1928 | } | |
1929 | ||
1930 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
1931 | { | |
1932 | fprintf (dump_file, "Simplified\n "); | |
75a70cf9 | 1933 | print_gimple_stmt (dump_file, stmt, 0, dump_flags); |
4ee9c684 | 1934 | } |
1935 | ||
75a70cf9 | 1936 | old_stmt = stmt; |
75a70cf9 | 1937 | if (!update_call_from_tree (&i, result)) |
0fefde02 | 1938 | { |
1939 | gimplify_and_update_call_from_tree (&i, result); | |
1940 | todoflags |= TODO_update_address_taken; | |
1941 | } | |
de6ed584 | 1942 | |
75a70cf9 | 1943 | stmt = gsi_stmt (i); |
4c5fd53c | 1944 | update_stmt (stmt); |
de6ed584 | 1945 | |
75a70cf9 | 1946 | if (maybe_clean_or_replace_eh_stmt (old_stmt, stmt) |
1947 | && gimple_purge_dead_eh_edges (bb)) | |
b36237eb | 1948 | cfg_changed = true; |
4ee9c684 | 1949 | |
1950 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
1951 | { | |
1952 | fprintf (dump_file, "to\n "); | |
75a70cf9 | 1953 | print_gimple_stmt (dump_file, stmt, 0, dump_flags); |
4ee9c684 | 1954 | fprintf (dump_file, "\n"); |
1955 | } | |
0a39fd54 | 1956 | |
1957 | /* Retry the same statement if it changed into another | |
1958 | builtin, there might be new opportunities now. */ | |
75a70cf9 | 1959 | if (gimple_code (stmt) != GIMPLE_CALL) |
0a39fd54 | 1960 | { |
75a70cf9 | 1961 | gsi_next (&i); |
0a39fd54 | 1962 | continue; |
1963 | } | |
75a70cf9 | 1964 | callee = gimple_call_fndecl (stmt); |
0a39fd54 | 1965 | if (!callee |
75a70cf9 | 1966 | || DECL_BUILT_IN_CLASS (callee) != BUILT_IN_NORMAL |
0a39fd54 | 1967 | || DECL_FUNCTION_CODE (callee) == fcode) |
75a70cf9 | 1968 | gsi_next (&i); |
4ee9c684 | 1969 | } |
1970 | } | |
48e1416a | 1971 | |
b36237eb | 1972 | /* Delete unreachable blocks. */ |
b1b7c0c4 | 1973 | if (cfg_changed) |
1974 | todoflags |= TODO_cleanup_cfg; | |
48e1416a | 1975 | |
b1b7c0c4 | 1976 | return todoflags; |
4ee9c684 | 1977 | } |
1978 | ||
41511585 | 1979 | |
48e1416a | 1980 | struct gimple_opt_pass pass_fold_builtins = |
4ee9c684 | 1981 | { |
20099e35 | 1982 | { |
1983 | GIMPLE_PASS, | |
4ee9c684 | 1984 | "fab", /* name */ |
1985 | NULL, /* gate */ | |
1986 | execute_fold_all_builtins, /* execute */ | |
1987 | NULL, /* sub */ | |
1988 | NULL, /* next */ | |
1989 | 0, /* static_pass_number */ | |
0b1615c1 | 1990 | TV_NONE, /* tv_id */ |
49290934 | 1991 | PROP_cfg | PROP_ssa, /* properties_required */ |
4ee9c684 | 1992 | 0, /* properties_provided */ |
1993 | 0, /* properties_destroyed */ | |
1994 | 0, /* todo_flags_start */ | |
909e5ecb | 1995 | TODO_dump_func |
1996 | | TODO_verify_ssa | |
20099e35 | 1997 | | TODO_update_ssa /* todo_flags_finish */ |
1998 | } | |
4ee9c684 | 1999 | }; |