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6de9cd9a | 1 | /* Conditional constant propagation pass for the GNU compiler. |
66647d44 | 2 | Copyright (C) 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009 |
1e052c19 | 3 | Free Software Foundation, Inc. |
6de9cd9a DN |
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. | |
8 | ||
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 | |
9dcd6f09 | 11 | Free Software Foundation; either version 3, or (at your option) any |
6de9cd9a DN |
12 | later version. |
13 | ||
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. | |
18 | ||
19 | You should have received a copy of the GNU General Public License | |
9dcd6f09 NC |
20 | along with GCC; see the file COPYING3. If not see |
21 | <http://www.gnu.org/licenses/>. */ | |
6de9cd9a | 22 | |
0bca51f0 DN |
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 | ||
106dec71 ZD |
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. | |
0bca51f0 DN |
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. | |
66 | ||
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 | |
38635499 DN |
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, | |
0bca51f0 | 138 | |
38635499 | 139 | # a_5 = VDEF <a_4> |
0bca51f0 DN |
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 | ||
106dec71 ZD |
149 | Note that the initial value of virtual operands is VARYING, not |
150 | UNDEFINED. Consider, for instance global variables: | |
0bca51f0 DN |
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 | |
106dec71 | 168 | would erroneously optimize the above into 'return 3;'. |
0bca51f0 DN |
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. | |
6de9cd9a DN |
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" | |
6de9cd9a | 192 | #include "tree.h" |
750628d8 | 193 | #include "flags.h" |
6de9cd9a DN |
194 | #include "rtl.h" |
195 | #include "tm_p.h" | |
750628d8 | 196 | #include "ggc.h" |
6de9cd9a | 197 | #include "basic-block.h" |
750628d8 | 198 | #include "output.h" |
750628d8 DN |
199 | #include "expr.h" |
200 | #include "function.h" | |
6de9cd9a | 201 | #include "diagnostic.h" |
750628d8 | 202 | #include "timevar.h" |
6de9cd9a | 203 | #include "tree-dump.h" |
750628d8 | 204 | #include "tree-flow.h" |
6de9cd9a | 205 | #include "tree-pass.h" |
750628d8 | 206 | #include "tree-ssa-propagate.h" |
53a8f709 | 207 | #include "value-prof.h" |
750628d8 | 208 | #include "langhooks.h" |
ae3df618 | 209 | #include "target.h" |
6ac01510 | 210 | #include "toplev.h" |
74fe548b | 211 | #include "dbgcnt.h" |
6de9cd9a DN |
212 | |
213 | ||
214 | /* Possible lattice values. */ | |
215 | typedef enum | |
216 | { | |
106dec71 | 217 | UNINITIALIZED, |
6de9cd9a DN |
218 | UNDEFINED, |
219 | CONSTANT, | |
220 | VARYING | |
0bca51f0 | 221 | } ccp_lattice_t; |
6de9cd9a | 222 | |
0bca51f0 DN |
223 | /* Array of propagated constant values. After propagation, |
224 | CONST_VAL[I].VALUE holds the constant value for SSA_NAME(I). If | |
225 | the constant is held in an SSA name representing a memory store | |
38635499 DN |
226 | (i.e., a VDEF), CONST_VAL[I].MEM_REF will contain the actual |
227 | memory reference used to store (i.e., the LHS of the assignment | |
228 | doing the store). */ | |
404f4351 | 229 | static prop_value_t *const_val; |
6de9cd9a | 230 | |
0bca51f0 | 231 | /* Dump constant propagation value VAL to file OUTF prefixed by PREFIX. */ |
95eec0d6 DB |
232 | |
233 | static void | |
0bca51f0 | 234 | dump_lattice_value (FILE *outf, const char *prefix, prop_value_t val) |
95eec0d6 | 235 | { |
750628d8 | 236 | switch (val.lattice_val) |
95eec0d6 | 237 | { |
0bca51f0 DN |
238 | case UNINITIALIZED: |
239 | fprintf (outf, "%sUNINITIALIZED", prefix); | |
240 | break; | |
750628d8 DN |
241 | case UNDEFINED: |
242 | fprintf (outf, "%sUNDEFINED", prefix); | |
243 | break; | |
244 | case VARYING: | |
245 | fprintf (outf, "%sVARYING", prefix); | |
246 | break; | |
750628d8 DN |
247 | case CONSTANT: |
248 | fprintf (outf, "%sCONSTANT ", prefix); | |
0bca51f0 | 249 | print_generic_expr (outf, val.value, dump_flags); |
750628d8 DN |
250 | break; |
251 | default: | |
1e128c5f | 252 | gcc_unreachable (); |
750628d8 | 253 | } |
95eec0d6 | 254 | } |
6de9cd9a | 255 | |
6de9cd9a | 256 | |
0bca51f0 DN |
257 | /* Print lattice value VAL to stderr. */ |
258 | ||
259 | void debug_lattice_value (prop_value_t val); | |
260 | ||
261 | void | |
262 | debug_lattice_value (prop_value_t val) | |
263 | { | |
264 | dump_lattice_value (stderr, "", val); | |
265 | fprintf (stderr, "\n"); | |
266 | } | |
6de9cd9a | 267 | |
6de9cd9a | 268 | |
726a989a | 269 | |
fc9962ee ZD |
270 | /* If SYM is a constant variable with known value, return the value. |
271 | NULL_TREE is returned otherwise. */ | |
272 | ||
ed97ddc6 | 273 | tree |
fc9962ee ZD |
274 | get_symbol_constant_value (tree sym) |
275 | { | |
276 | if (TREE_STATIC (sym) | |
5006671f | 277 | && TREE_READONLY (sym)) |
fc9962ee ZD |
278 | { |
279 | tree val = DECL_INITIAL (sym); | |
62bc00e2 RG |
280 | if (val) |
281 | { | |
282 | STRIP_USELESS_TYPE_CONVERSION (val); | |
283 | if (is_gimple_min_invariant (val)) | |
75ccc1e7 RG |
284 | { |
285 | if (TREE_CODE (val) == ADDR_EXPR) | |
286 | { | |
287 | tree base = get_base_address (TREE_OPERAND (val, 0)); | |
288 | if (base && TREE_CODE (base) == VAR_DECL) | |
289 | add_referenced_var (base); | |
290 | } | |
291 | return val; | |
292 | } | |
62bc00e2 | 293 | } |
b0940154 | 294 | /* Variables declared 'const' without an initializer |
fa10beec | 295 | have zero as the initializer if they may not be |
ed97ddc6 | 296 | overridden at link or run time. */ |
b0940154 | 297 | if (!val |
98b80692 | 298 | && !DECL_EXTERNAL (sym) |
ed97ddc6 | 299 | && targetm.binds_local_p (sym) |
b0940154 AP |
300 | && (INTEGRAL_TYPE_P (TREE_TYPE (sym)) |
301 | || SCALAR_FLOAT_TYPE_P (TREE_TYPE (sym)))) | |
98b80692 | 302 | return fold_convert (TREE_TYPE (sym), integer_zero_node); |
fc9962ee ZD |
303 | } |
304 | ||
305 | return NULL_TREE; | |
306 | } | |
688e936d | 307 | |
0bca51f0 DN |
308 | /* Compute a default value for variable VAR and store it in the |
309 | CONST_VAL array. The following rules are used to get default | |
310 | values: | |
95eec0d6 | 311 | |
0bca51f0 DN |
312 | 1- Global and static variables that are declared constant are |
313 | considered CONSTANT. | |
314 | ||
315 | 2- Any other value is considered UNDEFINED. This is useful when | |
750628d8 DN |
316 | considering PHI nodes. PHI arguments that are undefined do not |
317 | change the constant value of the PHI node, which allows for more | |
0bca51f0 | 318 | constants to be propagated. |
6de9cd9a | 319 | |
caf55296 | 320 | 3- Variables defined by statements other than assignments and PHI |
0bca51f0 | 321 | nodes are considered VARYING. |
6de9cd9a | 322 | |
caf55296 | 323 | 4- Initial values of variables that are not GIMPLE registers are |
106dec71 | 324 | considered VARYING. */ |
6de9cd9a | 325 | |
0bca51f0 DN |
326 | static prop_value_t |
327 | get_default_value (tree var) | |
328 | { | |
329 | tree sym = SSA_NAME_VAR (var); | |
dce2b2f6 | 330 | prop_value_t val = { UNINITIALIZED, NULL_TREE }; |
e8114fba RG |
331 | gimple stmt; |
332 | ||
333 | stmt = SSA_NAME_DEF_STMT (var); | |
334 | ||
335 | if (gimple_nop_p (stmt)) | |
6de9cd9a | 336 | { |
e8114fba RG |
337 | /* Variables defined by an empty statement are those used |
338 | before being initialized. If VAR is a local variable, we | |
339 | can assume initially that it is UNDEFINED, otherwise we must | |
340 | consider it VARYING. */ | |
341 | if (is_gimple_reg (sym) && TREE_CODE (sym) != PARM_DECL) | |
342 | val.lattice_val = UNDEFINED; | |
343 | else | |
344 | val.lattice_val = VARYING; | |
6de9cd9a | 345 | } |
e8114fba RG |
346 | else if (is_gimple_assign (stmt) |
347 | /* Value-returning GIMPLE_CALL statements assign to | |
348 | a variable, and are treated similarly to GIMPLE_ASSIGN. */ | |
349 | || (is_gimple_call (stmt) | |
350 | && gimple_call_lhs (stmt) != NULL_TREE) | |
351 | || gimple_code (stmt) == GIMPLE_PHI) | |
750628d8 | 352 | { |
e8114fba RG |
353 | tree cst; |
354 | if (gimple_assign_single_p (stmt) | |
355 | && DECL_P (gimple_assign_rhs1 (stmt)) | |
356 | && (cst = get_symbol_constant_value (gimple_assign_rhs1 (stmt)))) | |
0bca51f0 | 357 | { |
e8114fba RG |
358 | val.lattice_val = CONSTANT; |
359 | val.value = cst; | |
0bca51f0 DN |
360 | } |
361 | else | |
e8114fba RG |
362 | /* Any other variable defined by an assignment or a PHI node |
363 | is considered UNDEFINED. */ | |
364 | val.lattice_val = UNDEFINED; | |
365 | } | |
366 | else | |
367 | { | |
368 | /* Otherwise, VAR will never take on a constant value. */ | |
369 | val.lattice_val = VARYING; | |
750628d8 | 370 | } |
6de9cd9a | 371 | |
750628d8 DN |
372 | return val; |
373 | } | |
6de9cd9a | 374 | |
6de9cd9a | 375 | |
106dec71 | 376 | /* Get the constant value associated with variable VAR. */ |
6de9cd9a | 377 | |
106dec71 ZD |
378 | static inline prop_value_t * |
379 | get_value (tree var) | |
0bca51f0 | 380 | { |
ed97ddc6 | 381 | prop_value_t *val; |
106dec71 | 382 | |
ed97ddc6 RG |
383 | if (const_val == NULL) |
384 | return NULL; | |
385 | ||
386 | val = &const_val[SSA_NAME_VERSION (var)]; | |
106dec71 | 387 | if (val->lattice_val == UNINITIALIZED) |
6de9cd9a DN |
388 | *val = get_default_value (var); |
389 | ||
390 | return val; | |
391 | } | |
392 | ||
106dec71 ZD |
393 | /* Sets the value associated with VAR to VARYING. */ |
394 | ||
395 | static inline void | |
396 | set_value_varying (tree var) | |
397 | { | |
398 | prop_value_t *val = &const_val[SSA_NAME_VERSION (var)]; | |
399 | ||
400 | val->lattice_val = VARYING; | |
401 | val->value = NULL_TREE; | |
106dec71 | 402 | } |
6de9cd9a | 403 | |
fbb5445b L |
404 | /* For float types, modify the value of VAL to make ccp work correctly |
405 | for non-standard values (-0, NaN): | |
406 | ||
407 | If HONOR_SIGNED_ZEROS is false, and VAL = -0, we canonicalize it to 0. | |
408 | If HONOR_NANS is false, and VAL is NaN, we canonicalize it to UNDEFINED. | |
409 | This is to fix the following problem (see PR 29921): Suppose we have | |
410 | ||
411 | x = 0.0 * y | |
412 | ||
413 | and we set value of y to NaN. This causes value of x to be set to NaN. | |
414 | When we later determine that y is in fact VARYING, fold uses the fact | |
415 | that HONOR_NANS is false, and we try to change the value of x to 0, | |
416 | causing an ICE. With HONOR_NANS being false, the real appearance of | |
417 | NaN would cause undefined behavior, though, so claiming that y (and x) | |
418 | are UNDEFINED initially is correct. */ | |
419 | ||
420 | static void | |
421 | canonicalize_float_value (prop_value_t *val) | |
422 | { | |
423 | enum machine_mode mode; | |
424 | tree type; | |
425 | REAL_VALUE_TYPE d; | |
426 | ||
427 | if (val->lattice_val != CONSTANT | |
428 | || TREE_CODE (val->value) != REAL_CST) | |
429 | return; | |
430 | ||
431 | d = TREE_REAL_CST (val->value); | |
432 | type = TREE_TYPE (val->value); | |
433 | mode = TYPE_MODE (type); | |
434 | ||
435 | if (!HONOR_SIGNED_ZEROS (mode) | |
436 | && REAL_VALUE_MINUS_ZERO (d)) | |
437 | { | |
438 | val->value = build_real (type, dconst0); | |
439 | return; | |
440 | } | |
441 | ||
442 | if (!HONOR_NANS (mode) | |
443 | && REAL_VALUE_ISNAN (d)) | |
444 | { | |
445 | val->lattice_val = UNDEFINED; | |
446 | val->value = NULL; | |
fbb5445b L |
447 | return; |
448 | } | |
449 | } | |
450 | ||
0bca51f0 DN |
451 | /* Set the value for variable VAR to NEW_VAL. Return true if the new |
452 | value is different from VAR's previous value. */ | |
6de9cd9a | 453 | |
750628d8 | 454 | static bool |
0bca51f0 | 455 | set_lattice_value (tree var, prop_value_t new_val) |
6de9cd9a | 456 | { |
106dec71 | 457 | prop_value_t *old_val = get_value (var); |
0bca51f0 | 458 | |
fbb5445b L |
459 | canonicalize_float_value (&new_val); |
460 | ||
0bca51f0 | 461 | /* Lattice transitions must always be monotonically increasing in |
106dec71 ZD |
462 | value. If *OLD_VAL and NEW_VAL are the same, return false to |
463 | inform the caller that this was a non-transition. */ | |
464 | ||
fc9962ee | 465 | gcc_assert (old_val->lattice_val < new_val.lattice_val |
0bca51f0 | 466 | || (old_val->lattice_val == new_val.lattice_val |
fc9962ee | 467 | && ((!old_val->value && !new_val.value) |
dce2b2f6 | 468 | || operand_equal_p (old_val->value, new_val.value, 0)))); |
0bca51f0 DN |
469 | |
470 | if (old_val->lattice_val != new_val.lattice_val) | |
6de9cd9a | 471 | { |
750628d8 DN |
472 | if (dump_file && (dump_flags & TDF_DETAILS)) |
473 | { | |
0bca51f0 | 474 | dump_lattice_value (dump_file, "Lattice value changed to ", new_val); |
106dec71 | 475 | fprintf (dump_file, ". Adding SSA edges to worklist.\n"); |
750628d8 DN |
476 | } |
477 | ||
0bca51f0 DN |
478 | *old_val = new_val; |
479 | ||
106dec71 ZD |
480 | gcc_assert (new_val.lattice_val != UNDEFINED); |
481 | return true; | |
6de9cd9a | 482 | } |
750628d8 DN |
483 | |
484 | return false; | |
6de9cd9a DN |
485 | } |
486 | ||
487 | ||
0bca51f0 | 488 | /* Return the likely CCP lattice value for STMT. |
6de9cd9a | 489 | |
750628d8 | 490 | If STMT has no operands, then return CONSTANT. |
6de9cd9a | 491 | |
7f879c96 RG |
492 | Else if undefinedness of operands of STMT cause its value to be |
493 | undefined, then return UNDEFINED. | |
6de9cd9a | 494 | |
750628d8 | 495 | Else if any operands of STMT are constants, then return CONSTANT. |
6de9cd9a | 496 | |
750628d8 | 497 | Else return VARYING. */ |
6de9cd9a | 498 | |
0bca51f0 | 499 | static ccp_lattice_t |
726a989a | 500 | likely_value (gimple stmt) |
750628d8 | 501 | { |
7f879c96 | 502 | bool has_constant_operand, has_undefined_operand, all_undefined_operands; |
750628d8 DN |
503 | tree use; |
504 | ssa_op_iter iter; | |
e8114fba | 505 | unsigned i; |
6de9cd9a | 506 | |
e0c68ce9 | 507 | enum gimple_code code = gimple_code (stmt); |
726a989a RB |
508 | |
509 | /* This function appears to be called only for assignments, calls, | |
510 | conditionals, and switches, due to the logic in visit_stmt. */ | |
511 | gcc_assert (code == GIMPLE_ASSIGN | |
512 | || code == GIMPLE_CALL | |
513 | || code == GIMPLE_COND | |
514 | || code == GIMPLE_SWITCH); | |
0bca51f0 DN |
515 | |
516 | /* If the statement has volatile operands, it won't fold to a | |
517 | constant value. */ | |
726a989a | 518 | if (gimple_has_volatile_ops (stmt)) |
0bca51f0 DN |
519 | return VARYING; |
520 | ||
726a989a | 521 | /* Arrive here for more complex cases. */ |
106dec71 | 522 | has_constant_operand = false; |
7f879c96 RG |
523 | has_undefined_operand = false; |
524 | all_undefined_operands = true; | |
e8114fba | 525 | FOR_EACH_SSA_TREE_OPERAND (use, stmt, iter, SSA_OP_USE) |
750628d8 | 526 | { |
106dec71 | 527 | prop_value_t *val = get_value (use); |
750628d8 | 528 | |
106dec71 | 529 | if (val->lattice_val == UNDEFINED) |
7f879c96 RG |
530 | has_undefined_operand = true; |
531 | else | |
532 | all_undefined_operands = false; | |
0bca51f0 | 533 | |
750628d8 | 534 | if (val->lattice_val == CONSTANT) |
106dec71 | 535 | has_constant_operand = true; |
6de9cd9a | 536 | } |
750628d8 | 537 | |
5006671f RG |
538 | /* There may be constants in regular rhs operands. For calls we |
539 | have to ignore lhs, fndecl and static chain, otherwise only | |
540 | the lhs. */ | |
541 | for (i = (is_gimple_call (stmt) ? 2 : 0) + gimple_has_lhs (stmt); | |
e8114fba RG |
542 | i < gimple_num_ops (stmt); ++i) |
543 | { | |
544 | tree op = gimple_op (stmt, i); | |
545 | if (!op || TREE_CODE (op) == SSA_NAME) | |
546 | continue; | |
547 | if (is_gimple_min_invariant (op)) | |
548 | has_constant_operand = true; | |
549 | } | |
550 | ||
7f879c96 RG |
551 | /* If the operation combines operands like COMPLEX_EXPR make sure to |
552 | not mark the result UNDEFINED if only one part of the result is | |
553 | undefined. */ | |
726a989a | 554 | if (has_undefined_operand && all_undefined_operands) |
7f879c96 | 555 | return UNDEFINED; |
726a989a | 556 | else if (code == GIMPLE_ASSIGN && has_undefined_operand) |
7f879c96 | 557 | { |
726a989a | 558 | switch (gimple_assign_rhs_code (stmt)) |
7f879c96 RG |
559 | { |
560 | /* Unary operators are handled with all_undefined_operands. */ | |
561 | case PLUS_EXPR: | |
562 | case MINUS_EXPR: | |
7f879c96 | 563 | case POINTER_PLUS_EXPR: |
7f879c96 RG |
564 | /* Not MIN_EXPR, MAX_EXPR. One VARYING operand may be selected. |
565 | Not bitwise operators, one VARYING operand may specify the | |
566 | result completely. Not logical operators for the same reason. | |
0cedb9e9 RG |
567 | Not COMPLEX_EXPR as one VARYING operand makes the result partly |
568 | not UNDEFINED. Not *DIV_EXPR, comparisons and shifts because | |
569 | the undefined operand may be promoted. */ | |
7f879c96 RG |
570 | return UNDEFINED; |
571 | ||
572 | default: | |
573 | ; | |
574 | } | |
575 | } | |
576 | /* If there was an UNDEFINED operand but the result may be not UNDEFINED | |
577 | fall back to VARYING even if there were CONSTANT operands. */ | |
578 | if (has_undefined_operand) | |
579 | return VARYING; | |
580 | ||
e8114fba RG |
581 | /* We do not consider virtual operands here -- load from read-only |
582 | memory may have only VARYING virtual operands, but still be | |
583 | constant. */ | |
106dec71 | 584 | if (has_constant_operand |
e8114fba | 585 | || gimple_references_memory_p (stmt)) |
0bca51f0 DN |
586 | return CONSTANT; |
587 | ||
106dec71 | 588 | return VARYING; |
6de9cd9a DN |
589 | } |
590 | ||
106dec71 ZD |
591 | /* Returns true if STMT cannot be constant. */ |
592 | ||
593 | static bool | |
726a989a | 594 | surely_varying_stmt_p (gimple stmt) |
106dec71 ZD |
595 | { |
596 | /* If the statement has operands that we cannot handle, it cannot be | |
597 | constant. */ | |
726a989a | 598 | if (gimple_has_volatile_ops (stmt)) |
106dec71 ZD |
599 | return true; |
600 | ||
174ef36d RG |
601 | /* If it is a call and does not return a value or is not a |
602 | builtin and not an indirect call, it is varying. */ | |
726a989a | 603 | if (is_gimple_call (stmt)) |
174ef36d RG |
604 | { |
605 | tree fndecl; | |
606 | if (!gimple_call_lhs (stmt) | |
607 | || ((fndecl = gimple_call_fndecl (stmt)) != NULL_TREE | |
99f536cc | 608 | && !DECL_BUILT_IN (fndecl))) |
174ef36d RG |
609 | return true; |
610 | } | |
106dec71 | 611 | |
e8114fba | 612 | /* Any other store operation is not interesting. */ |
5006671f | 613 | else if (gimple_vdef (stmt)) |
e8114fba RG |
614 | return true; |
615 | ||
106dec71 ZD |
616 | /* Anything other than assignments and conditional jumps are not |
617 | interesting for CCP. */ | |
726a989a | 618 | if (gimple_code (stmt) != GIMPLE_ASSIGN |
174ef36d RG |
619 | && gimple_code (stmt) != GIMPLE_COND |
620 | && gimple_code (stmt) != GIMPLE_SWITCH | |
621 | && gimple_code (stmt) != GIMPLE_CALL) | |
106dec71 ZD |
622 | return true; |
623 | ||
624 | return false; | |
625 | } | |
6de9cd9a | 626 | |
750628d8 | 627 | /* Initialize local data structures for CCP. */ |
6de9cd9a DN |
628 | |
629 | static void | |
750628d8 | 630 | ccp_initialize (void) |
6de9cd9a | 631 | { |
750628d8 | 632 | basic_block bb; |
6de9cd9a | 633 | |
b9eae1a9 | 634 | const_val = XCNEWVEC (prop_value_t, num_ssa_names); |
6de9cd9a | 635 | |
750628d8 DN |
636 | /* Initialize simulation flags for PHI nodes and statements. */ |
637 | FOR_EACH_BB (bb) | |
6de9cd9a | 638 | { |
726a989a | 639 | gimple_stmt_iterator i; |
6de9cd9a | 640 | |
726a989a | 641 | for (i = gsi_start_bb (bb); !gsi_end_p (i); gsi_next (&i)) |
750628d8 | 642 | { |
726a989a | 643 | gimple stmt = gsi_stmt (i); |
106dec71 | 644 | bool is_varying = surely_varying_stmt_p (stmt); |
6de9cd9a | 645 | |
106dec71 | 646 | if (is_varying) |
750628d8 | 647 | { |
0bca51f0 DN |
648 | tree def; |
649 | ssa_op_iter iter; | |
650 | ||
651 | /* If the statement will not produce a constant, mark | |
652 | all its outputs VARYING. */ | |
653 | FOR_EACH_SSA_TREE_OPERAND (def, stmt, iter, SSA_OP_ALL_DEFS) | |
e8114fba | 654 | set_value_varying (def); |
750628d8 | 655 | } |
726a989a | 656 | prop_set_simulate_again (stmt, !is_varying); |
750628d8 | 657 | } |
6de9cd9a DN |
658 | } |
659 | ||
726a989a RB |
660 | /* Now process PHI nodes. We never clear the simulate_again flag on |
661 | phi nodes, since we do not know which edges are executable yet, | |
662 | except for phi nodes for virtual operands when we do not do store ccp. */ | |
750628d8 | 663 | FOR_EACH_BB (bb) |
6de9cd9a | 664 | { |
726a989a | 665 | gimple_stmt_iterator i; |
750628d8 | 666 | |
726a989a RB |
667 | for (i = gsi_start_phis (bb); !gsi_end_p (i); gsi_next (&i)) |
668 | { | |
669 | gimple phi = gsi_stmt (i); | |
670 | ||
dce2b2f6 | 671 | if (!is_gimple_reg (gimple_phi_result (phi))) |
726a989a | 672 | prop_set_simulate_again (phi, false); |
106dec71 | 673 | else |
726a989a | 674 | prop_set_simulate_again (phi, true); |
750628d8 | 675 | } |
6de9cd9a | 676 | } |
750628d8 | 677 | } |
6de9cd9a | 678 | |
74fe548b XDL |
679 | /* Debug count support. Reset the values of ssa names |
680 | VARYING when the total number ssa names analyzed is | |
681 | beyond the debug count specified. */ | |
682 | ||
683 | static void | |
684 | do_dbg_cnt (void) | |
685 | { | |
686 | unsigned i; | |
687 | for (i = 0; i < num_ssa_names; i++) | |
688 | { | |
689 | if (!dbg_cnt (ccp)) | |
690 | { | |
691 | const_val[i].lattice_val = VARYING; | |
692 | const_val[i].value = NULL_TREE; | |
693 | } | |
694 | } | |
695 | } | |
696 | ||
6de9cd9a | 697 | |
0bca51f0 | 698 | /* Do final substitution of propagated values, cleanup the flowgraph and |
3253eafb | 699 | free allocated storage. |
6de9cd9a | 700 | |
3253eafb JH |
701 | Return TRUE when something was optimized. */ |
702 | ||
703 | static bool | |
0bca51f0 | 704 | ccp_finalize (void) |
6de9cd9a | 705 | { |
74fe548b XDL |
706 | bool something_changed; |
707 | ||
708 | do_dbg_cnt (); | |
0bca51f0 | 709 | /* Perform substitutions based on the known constant values. */ |
74fe548b | 710 | something_changed = substitute_and_fold (const_val, false); |
6de9cd9a | 711 | |
0bca51f0 | 712 | free (const_val); |
ed97ddc6 | 713 | const_val = NULL; |
3253eafb | 714 | return something_changed;; |
6de9cd9a DN |
715 | } |
716 | ||
717 | ||
0bca51f0 DN |
718 | /* Compute the meet operator between *VAL1 and *VAL2. Store the result |
719 | in VAL1. | |
720 | ||
721 | any M UNDEFINED = any | |
0bca51f0 DN |
722 | any M VARYING = VARYING |
723 | Ci M Cj = Ci if (i == j) | |
724 | Ci M Cj = VARYING if (i != j) | |
106dec71 | 725 | */ |
6de9cd9a DN |
726 | |
727 | static void | |
0bca51f0 | 728 | ccp_lattice_meet (prop_value_t *val1, prop_value_t *val2) |
6de9cd9a | 729 | { |
0bca51f0 | 730 | if (val1->lattice_val == UNDEFINED) |
6de9cd9a | 731 | { |
0bca51f0 DN |
732 | /* UNDEFINED M any = any */ |
733 | *val1 = *val2; | |
750628d8 | 734 | } |
0bca51f0 | 735 | else if (val2->lattice_val == UNDEFINED) |
195da47b | 736 | { |
0bca51f0 DN |
737 | /* any M UNDEFINED = any |
738 | Nothing to do. VAL1 already contains the value we want. */ | |
739 | ; | |
195da47b | 740 | } |
0bca51f0 DN |
741 | else if (val1->lattice_val == VARYING |
742 | || val2->lattice_val == VARYING) | |
750628d8 | 743 | { |
0bca51f0 DN |
744 | /* any M VARYING = VARYING. */ |
745 | val1->lattice_val = VARYING; | |
746 | val1->value = NULL_TREE; | |
750628d8 | 747 | } |
0bca51f0 DN |
748 | else if (val1->lattice_val == CONSTANT |
749 | && val2->lattice_val == CONSTANT | |
dce2b2f6 | 750 | && simple_cst_equal (val1->value, val2->value) == 1) |
750628d8 | 751 | { |
0bca51f0 DN |
752 | /* Ci M Cj = Ci if (i == j) |
753 | Ci M Cj = VARYING if (i != j) | |
754 | ||
755 | If these two values come from memory stores, make sure that | |
756 | they come from the same memory reference. */ | |
757 | val1->lattice_val = CONSTANT; | |
758 | val1->value = val1->value; | |
750628d8 DN |
759 | } |
760 | else | |
761 | { | |
0bca51f0 DN |
762 | /* Any other combination is VARYING. */ |
763 | val1->lattice_val = VARYING; | |
764 | val1->value = NULL_TREE; | |
750628d8 | 765 | } |
6de9cd9a DN |
766 | } |
767 | ||
768 | ||
750628d8 DN |
769 | /* Loop through the PHI_NODE's parameters for BLOCK and compare their |
770 | lattice values to determine PHI_NODE's lattice value. The value of a | |
0bca51f0 | 771 | PHI node is determined calling ccp_lattice_meet with all the arguments |
750628d8 | 772 | of the PHI node that are incoming via executable edges. */ |
6de9cd9a | 773 | |
750628d8 | 774 | static enum ssa_prop_result |
726a989a | 775 | ccp_visit_phi_node (gimple phi) |
6de9cd9a | 776 | { |
726a989a | 777 | unsigned i; |
0bca51f0 | 778 | prop_value_t *old_val, new_val; |
6de9cd9a | 779 | |
750628d8 | 780 | if (dump_file && (dump_flags & TDF_DETAILS)) |
6de9cd9a | 781 | { |
750628d8 | 782 | fprintf (dump_file, "\nVisiting PHI node: "); |
726a989a | 783 | print_gimple_stmt (dump_file, phi, 0, dump_flags); |
6de9cd9a | 784 | } |
6de9cd9a | 785 | |
726a989a | 786 | old_val = get_value (gimple_phi_result (phi)); |
750628d8 DN |
787 | switch (old_val->lattice_val) |
788 | { | |
789 | case VARYING: | |
0bca51f0 | 790 | return SSA_PROP_VARYING; |
6de9cd9a | 791 | |
750628d8 DN |
792 | case CONSTANT: |
793 | new_val = *old_val; | |
794 | break; | |
6de9cd9a | 795 | |
750628d8 | 796 | case UNDEFINED: |
750628d8 | 797 | new_val.lattice_val = UNDEFINED; |
0bca51f0 | 798 | new_val.value = NULL_TREE; |
750628d8 | 799 | break; |
6de9cd9a | 800 | |
750628d8 | 801 | default: |
1e128c5f | 802 | gcc_unreachable (); |
750628d8 | 803 | } |
6de9cd9a | 804 | |
726a989a | 805 | for (i = 0; i < gimple_phi_num_args (phi); i++) |
750628d8 | 806 | { |
0bca51f0 DN |
807 | /* Compute the meet operator over all the PHI arguments flowing |
808 | through executable edges. */ | |
726a989a | 809 | edge e = gimple_phi_arg_edge (phi, i); |
6de9cd9a | 810 | |
750628d8 DN |
811 | if (dump_file && (dump_flags & TDF_DETAILS)) |
812 | { | |
813 | fprintf (dump_file, | |
814 | "\n Argument #%d (%d -> %d %sexecutable)\n", | |
815 | i, e->src->index, e->dest->index, | |
816 | (e->flags & EDGE_EXECUTABLE) ? "" : "not "); | |
817 | } | |
818 | ||
819 | /* If the incoming edge is executable, Compute the meet operator for | |
820 | the existing value of the PHI node and the current PHI argument. */ | |
821 | if (e->flags & EDGE_EXECUTABLE) | |
822 | { | |
726a989a | 823 | tree arg = gimple_phi_arg (phi, i)->def; |
0bca51f0 | 824 | prop_value_t arg_val; |
6de9cd9a | 825 | |
0bca51f0 | 826 | if (is_gimple_min_invariant (arg)) |
750628d8 | 827 | { |
0bca51f0 DN |
828 | arg_val.lattice_val = CONSTANT; |
829 | arg_val.value = arg; | |
750628d8 DN |
830 | } |
831 | else | |
106dec71 | 832 | arg_val = *(get_value (arg)); |
6de9cd9a | 833 | |
0bca51f0 | 834 | ccp_lattice_meet (&new_val, &arg_val); |
6de9cd9a | 835 | |
750628d8 DN |
836 | if (dump_file && (dump_flags & TDF_DETAILS)) |
837 | { | |
838 | fprintf (dump_file, "\t"); | |
0bca51f0 DN |
839 | print_generic_expr (dump_file, arg, dump_flags); |
840 | dump_lattice_value (dump_file, "\tValue: ", arg_val); | |
750628d8 DN |
841 | fprintf (dump_file, "\n"); |
842 | } | |
6de9cd9a | 843 | |
750628d8 DN |
844 | if (new_val.lattice_val == VARYING) |
845 | break; | |
846 | } | |
847 | } | |
6de9cd9a DN |
848 | |
849 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
750628d8 DN |
850 | { |
851 | dump_lattice_value (dump_file, "\n PHI node value: ", new_val); | |
852 | fprintf (dump_file, "\n\n"); | |
853 | } | |
854 | ||
106dec71 | 855 | /* Make the transition to the new value. */ |
726a989a | 856 | if (set_lattice_value (gimple_phi_result (phi), new_val)) |
750628d8 DN |
857 | { |
858 | if (new_val.lattice_val == VARYING) | |
859 | return SSA_PROP_VARYING; | |
860 | else | |
861 | return SSA_PROP_INTERESTING; | |
862 | } | |
863 | else | |
864 | return SSA_PROP_NOT_INTERESTING; | |
6de9cd9a DN |
865 | } |
866 | ||
f7c0ffb4 RG |
867 | /* Return true if we may propagate the address expression ADDR into the |
868 | dereference DEREF and cancel them. */ | |
869 | ||
870 | bool | |
871 | may_propagate_address_into_dereference (tree addr, tree deref) | |
872 | { | |
873 | gcc_assert (INDIRECT_REF_P (deref) | |
874 | && TREE_CODE (addr) == ADDR_EXPR); | |
875 | ||
03375368 JJ |
876 | /* Don't propagate if ADDR's operand has incomplete type. */ |
877 | if (!COMPLETE_TYPE_P (TREE_TYPE (TREE_OPERAND (addr, 0)))) | |
878 | return false; | |
879 | ||
f7c0ffb4 RG |
880 | /* If the address is invariant then we do not need to preserve restrict |
881 | qualifications. But we do need to preserve volatile qualifiers until | |
882 | we can annotate the folded dereference itself properly. */ | |
883 | if (is_gimple_min_invariant (addr) | |
884 | && (!TREE_THIS_VOLATILE (deref) | |
885 | || TYPE_VOLATILE (TREE_TYPE (addr)))) | |
886 | return useless_type_conversion_p (TREE_TYPE (deref), | |
887 | TREE_TYPE (TREE_OPERAND (addr, 0))); | |
888 | ||
889 | /* Else both the address substitution and the folding must result in | |
890 | a valid useless type conversion sequence. */ | |
891 | return (useless_type_conversion_p (TREE_TYPE (TREE_OPERAND (deref, 0)), | |
892 | TREE_TYPE (addr)) | |
893 | && useless_type_conversion_p (TREE_TYPE (deref), | |
894 | TREE_TYPE (TREE_OPERAND (addr, 0)))); | |
895 | } | |
6de9cd9a | 896 | |
750628d8 DN |
897 | /* CCP specific front-end to the non-destructive constant folding |
898 | routines. | |
6de9cd9a DN |
899 | |
900 | Attempt to simplify the RHS of STMT knowing that one or more | |
901 | operands are constants. | |
902 | ||
903 | If simplification is possible, return the simplified RHS, | |
726a989a | 904 | otherwise return the original RHS or NULL_TREE. */ |
6de9cd9a DN |
905 | |
906 | static tree | |
726a989a | 907 | ccp_fold (gimple stmt) |
6de9cd9a | 908 | { |
726a989a | 909 | switch (gimple_code (stmt)) |
0bca51f0 | 910 | { |
726a989a RB |
911 | case GIMPLE_ASSIGN: |
912 | { | |
913 | enum tree_code subcode = gimple_assign_rhs_code (stmt); | |
914 | ||
915 | switch (get_gimple_rhs_class (subcode)) | |
916 | { | |
917 | case GIMPLE_SINGLE_RHS: | |
918 | { | |
919 | tree rhs = gimple_assign_rhs1 (stmt); | |
920 | enum tree_code_class kind = TREE_CODE_CLASS (subcode); | |
921 | ||
922 | if (TREE_CODE (rhs) == SSA_NAME) | |
923 | { | |
924 | /* If the RHS is an SSA_NAME, return its known constant value, | |
925 | if any. */ | |
926 | return get_value (rhs)->value; | |
927 | } | |
928 | /* Handle propagating invariant addresses into address operations. | |
929 | The folding we do here matches that in tree-ssa-forwprop.c. */ | |
930 | else if (TREE_CODE (rhs) == ADDR_EXPR) | |
931 | { | |
932 | tree *base; | |
933 | base = &TREE_OPERAND (rhs, 0); | |
934 | while (handled_component_p (*base)) | |
935 | base = &TREE_OPERAND (*base, 0); | |
936 | if (TREE_CODE (*base) == INDIRECT_REF | |
937 | && TREE_CODE (TREE_OPERAND (*base, 0)) == SSA_NAME) | |
938 | { | |
939 | prop_value_t *val = get_value (TREE_OPERAND (*base, 0)); | |
940 | if (val->lattice_val == CONSTANT | |
941 | && TREE_CODE (val->value) == ADDR_EXPR | |
f7c0ffb4 RG |
942 | && may_propagate_address_into_dereference |
943 | (val->value, *base)) | |
726a989a RB |
944 | { |
945 | /* We need to return a new tree, not modify the IL | |
946 | or share parts of it. So play some tricks to | |
947 | avoid manually building it. */ | |
948 | tree ret, save = *base; | |
949 | *base = TREE_OPERAND (val->value, 0); | |
950 | ret = unshare_expr (rhs); | |
951 | recompute_tree_invariant_for_addr_expr (ret); | |
952 | *base = save; | |
953 | return ret; | |
954 | } | |
955 | } | |
956 | } | |
6de9cd9a | 957 | |
726a989a | 958 | if (kind == tcc_reference) |
c76a1f18 | 959 | { |
4bad83f5 RG |
960 | if ((TREE_CODE (rhs) == VIEW_CONVERT_EXPR |
961 | || TREE_CODE (rhs) == REALPART_EXPR | |
962 | || TREE_CODE (rhs) == IMAGPART_EXPR) | |
c76a1f18 RG |
963 | && TREE_CODE (TREE_OPERAND (rhs, 0)) == SSA_NAME) |
964 | { | |
965 | prop_value_t *val = get_value (TREE_OPERAND (rhs, 0)); | |
966 | if (val->lattice_val == CONSTANT) | |
4bad83f5 | 967 | return fold_unary (TREE_CODE (rhs), |
c76a1f18 RG |
968 | TREE_TYPE (rhs), val->value); |
969 | } | |
e8114fba RG |
970 | else if (TREE_CODE (rhs) == INDIRECT_REF |
971 | && TREE_CODE (TREE_OPERAND (rhs, 0)) == SSA_NAME) | |
972 | { | |
973 | prop_value_t *val = get_value (TREE_OPERAND (rhs, 0)); | |
974 | if (val->lattice_val == CONSTANT | |
975 | && TREE_CODE (val->value) == ADDR_EXPR | |
976 | && useless_type_conversion_p (TREE_TYPE (rhs), | |
977 | TREE_TYPE (TREE_TYPE (val->value)))) | |
978 | rhs = TREE_OPERAND (val->value, 0); | |
979 | } | |
c76a1f18 RG |
980 | return fold_const_aggregate_ref (rhs); |
981 | } | |
726a989a RB |
982 | else if (kind == tcc_declaration) |
983 | return get_symbol_constant_value (rhs); | |
984 | return rhs; | |
985 | } | |
986 | ||
987 | case GIMPLE_UNARY_RHS: | |
988 | { | |
989 | /* Handle unary operators that can appear in GIMPLE form. | |
990 | Note that we know the single operand must be a constant, | |
991 | so this should almost always return a simplified RHS. */ | |
992 | tree lhs = gimple_assign_lhs (stmt); | |
993 | tree op0 = gimple_assign_rhs1 (stmt); | |
994 | ||
995 | /* Simplify the operand down to a constant. */ | |
996 | if (TREE_CODE (op0) == SSA_NAME) | |
997 | { | |
998 | prop_value_t *val = get_value (op0); | |
999 | if (val->lattice_val == CONSTANT) | |
1000 | op0 = get_value (op0)->value; | |
1001 | } | |
1002 | ||
1003 | /* Conversions are useless for CCP purposes if they are | |
1004 | value-preserving. Thus the restrictions that | |
1005 | useless_type_conversion_p places for pointer type conversions | |
1006 | do not apply here. Substitution later will only substitute to | |
1007 | allowed places. */ | |
1a87cf0c | 1008 | if (CONVERT_EXPR_CODE_P (subcode) |
99f536cc RG |
1009 | && POINTER_TYPE_P (TREE_TYPE (lhs)) |
1010 | && POINTER_TYPE_P (TREE_TYPE (op0)) | |
1011 | /* Do not allow differences in volatile qualification | |
1012 | as this might get us confused as to whether a | |
1013 | propagation destination statement is volatile | |
1014 | or not. See PR36988. */ | |
1015 | && (TYPE_VOLATILE (TREE_TYPE (TREE_TYPE (lhs))) | |
1016 | == TYPE_VOLATILE (TREE_TYPE (TREE_TYPE (op0))))) | |
1017 | { | |
1018 | tree tem; | |
1019 | /* Still try to generate a constant of correct type. */ | |
1020 | if (!useless_type_conversion_p (TREE_TYPE (lhs), | |
1021 | TREE_TYPE (op0)) | |
1022 | && ((tem = maybe_fold_offset_to_address | |
1023 | (op0, integer_zero_node, TREE_TYPE (lhs))) | |
1024 | != NULL_TREE)) | |
1025 | return tem; | |
1026 | return op0; | |
1027 | } | |
726a989a | 1028 | |
9bacafeb PB |
1029 | return fold_unary_ignore_overflow (subcode, |
1030 | gimple_expr_type (stmt), op0); | |
ff8b183b | 1031 | } |
726a989a RB |
1032 | |
1033 | case GIMPLE_BINARY_RHS: | |
1034 | { | |
1035 | /* Handle binary operators that can appear in GIMPLE form. */ | |
1036 | tree op0 = gimple_assign_rhs1 (stmt); | |
1037 | tree op1 = gimple_assign_rhs2 (stmt); | |
1038 | ||
1039 | /* Simplify the operands down to constants when appropriate. */ | |
1040 | if (TREE_CODE (op0) == SSA_NAME) | |
1041 | { | |
1042 | prop_value_t *val = get_value (op0); | |
1043 | if (val->lattice_val == CONSTANT) | |
1044 | op0 = val->value; | |
1045 | } | |
1046 | ||
1047 | if (TREE_CODE (op1) == SSA_NAME) | |
1048 | { | |
1049 | prop_value_t *val = get_value (op1); | |
1050 | if (val->lattice_val == CONSTANT) | |
1051 | op1 = val->value; | |
1052 | } | |
1053 | ||
99f536cc RG |
1054 | /* Fold &foo + CST into an invariant reference if possible. */ |
1055 | if (gimple_assign_rhs_code (stmt) == POINTER_PLUS_EXPR | |
1056 | && TREE_CODE (op0) == ADDR_EXPR | |
1057 | && TREE_CODE (op1) == INTEGER_CST) | |
1058 | { | |
1059 | tree lhs = gimple_assign_lhs (stmt); | |
1060 | tree tem = maybe_fold_offset_to_address (op0, op1, | |
1061 | TREE_TYPE (lhs)); | |
1062 | if (tem != NULL_TREE) | |
1063 | return tem; | |
1064 | } | |
1065 | ||
726a989a RB |
1066 | return fold_binary (subcode, gimple_expr_type (stmt), op0, op1); |
1067 | } | |
1068 | ||
1069 | default: | |
1070 | gcc_unreachable (); | |
1071 | } | |
1072 | } | |
1073 | break; | |
6de9cd9a | 1074 | |
726a989a | 1075 | case GIMPLE_CALL: |
174ef36d RG |
1076 | { |
1077 | tree fn = gimple_call_fn (stmt); | |
1078 | prop_value_t *val; | |
1079 | ||
1080 | if (TREE_CODE (fn) == SSA_NAME) | |
1081 | { | |
1082 | val = get_value (fn); | |
1083 | if (val->lattice_val == CONSTANT) | |
1084 | fn = val->value; | |
1085 | } | |
1086 | if (TREE_CODE (fn) == ADDR_EXPR | |
a135b1c4 | 1087 | && TREE_CODE (TREE_OPERAND (fn, 0)) == FUNCTION_DECL |
174ef36d RG |
1088 | && DECL_BUILT_IN (TREE_OPERAND (fn, 0))) |
1089 | { | |
1090 | tree *args = XALLOCAVEC (tree, gimple_call_num_args (stmt)); | |
1091 | tree call, retval; | |
1092 | unsigned i; | |
1093 | for (i = 0; i < gimple_call_num_args (stmt); ++i) | |
1094 | { | |
1095 | args[i] = gimple_call_arg (stmt, i); | |
1096 | if (TREE_CODE (args[i]) == SSA_NAME) | |
1097 | { | |
1098 | val = get_value (args[i]); | |
1099 | if (val->lattice_val == CONSTANT) | |
1100 | args[i] = val->value; | |
1101 | } | |
1102 | } | |
1103 | call = build_call_array (gimple_call_return_type (stmt), | |
1104 | fn, gimple_call_num_args (stmt), args); | |
1105 | retval = fold_call_expr (call, false); | |
1106 | if (retval) | |
1107 | /* fold_call_expr wraps the result inside a NOP_EXPR. */ | |
1108 | STRIP_NOPS (retval); | |
1109 | return retval; | |
1110 | } | |
1111 | return NULL_TREE; | |
1112 | } | |
6de9cd9a | 1113 | |
726a989a RB |
1114 | case GIMPLE_COND: |
1115 | { | |
1116 | /* Handle comparison operators that can appear in GIMPLE form. */ | |
1117 | tree op0 = gimple_cond_lhs (stmt); | |
1118 | tree op1 = gimple_cond_rhs (stmt); | |
1119 | enum tree_code code = gimple_cond_code (stmt); | |
1120 | ||
1121 | /* Simplify the operands down to constants when appropriate. */ | |
1122 | if (TREE_CODE (op0) == SSA_NAME) | |
1123 | { | |
1124 | prop_value_t *val = get_value (op0); | |
1125 | if (val->lattice_val == CONSTANT) | |
1126 | op0 = val->value; | |
1127 | } | |
1128 | ||
1129 | if (TREE_CODE (op1) == SSA_NAME) | |
1130 | { | |
1131 | prop_value_t *val = get_value (op1); | |
1132 | if (val->lattice_val == CONSTANT) | |
1133 | op1 = val->value; | |
1134 | } | |
1135 | ||
1136 | return fold_binary (code, boolean_type_node, op0, op1); | |
1137 | } | |
6de9cd9a | 1138 | |
726a989a RB |
1139 | case GIMPLE_SWITCH: |
1140 | { | |
1141 | tree rhs = gimple_switch_index (stmt); | |
87e1e42b | 1142 | |
726a989a RB |
1143 | if (TREE_CODE (rhs) == SSA_NAME) |
1144 | { | |
1145 | /* If the RHS is an SSA_NAME, return its known constant value, | |
1146 | if any. */ | |
1147 | return get_value (rhs)->value; | |
1148 | } | |
87e1e42b | 1149 | |
726a989a RB |
1150 | return rhs; |
1151 | } | |
00d382a8 | 1152 | |
726a989a RB |
1153 | default: |
1154 | gcc_unreachable (); | |
6de9cd9a | 1155 | } |
6de9cd9a DN |
1156 | } |
1157 | ||
1158 | ||
ae3df618 SB |
1159 | /* Return the tree representing the element referenced by T if T is an |
1160 | ARRAY_REF or COMPONENT_REF into constant aggregates. Return | |
1161 | NULL_TREE otherwise. */ | |
1162 | ||
ed97ddc6 | 1163 | tree |
ae3df618 SB |
1164 | fold_const_aggregate_ref (tree t) |
1165 | { | |
1166 | prop_value_t *value; | |
4038c495 GB |
1167 | tree base, ctor, idx, field; |
1168 | unsigned HOST_WIDE_INT cnt; | |
1169 | tree cfield, cval; | |
ae3df618 | 1170 | |
e8114fba RG |
1171 | if (TREE_CODE_CLASS (TREE_CODE (t)) == tcc_declaration) |
1172 | return get_symbol_constant_value (t); | |
1173 | ||
ae3df618 SB |
1174 | switch (TREE_CODE (t)) |
1175 | { | |
1176 | case ARRAY_REF: | |
1177 | /* Get a CONSTRUCTOR. If BASE is a VAR_DECL, get its | |
1178 | DECL_INITIAL. If BASE is a nested reference into another | |
1179 | ARRAY_REF or COMPONENT_REF, make a recursive call to resolve | |
1180 | the inner reference. */ | |
1181 | base = TREE_OPERAND (t, 0); | |
1182 | switch (TREE_CODE (base)) | |
1183 | { | |
1184 | case VAR_DECL: | |
1185 | if (!TREE_READONLY (base) | |
1186 | || TREE_CODE (TREE_TYPE (base)) != ARRAY_TYPE | |
1187 | || !targetm.binds_local_p (base)) | |
1188 | return NULL_TREE; | |
1189 | ||
1190 | ctor = DECL_INITIAL (base); | |
1191 | break; | |
1192 | ||
1193 | case ARRAY_REF: | |
1194 | case COMPONENT_REF: | |
1195 | ctor = fold_const_aggregate_ref (base); | |
1196 | break; | |
1197 | ||
87e1e42b RG |
1198 | case STRING_CST: |
1199 | case CONSTRUCTOR: | |
1200 | ctor = base; | |
1201 | break; | |
1202 | ||
ae3df618 SB |
1203 | default: |
1204 | return NULL_TREE; | |
1205 | } | |
1206 | ||
1207 | if (ctor == NULL_TREE | |
faaf1436 RG |
1208 | || (TREE_CODE (ctor) != CONSTRUCTOR |
1209 | && TREE_CODE (ctor) != STRING_CST) | |
ae3df618 SB |
1210 | || !TREE_STATIC (ctor)) |
1211 | return NULL_TREE; | |
1212 | ||
1213 | /* Get the index. If we have an SSA_NAME, try to resolve it | |
1214 | with the current lattice value for the SSA_NAME. */ | |
1215 | idx = TREE_OPERAND (t, 1); | |
1216 | switch (TREE_CODE (idx)) | |
1217 | { | |
1218 | case SSA_NAME: | |
106dec71 | 1219 | if ((value = get_value (idx)) |
ae3df618 SB |
1220 | && value->lattice_val == CONSTANT |
1221 | && TREE_CODE (value->value) == INTEGER_CST) | |
1222 | idx = value->value; | |
1223 | else | |
1224 | return NULL_TREE; | |
1225 | break; | |
1226 | ||
1227 | case INTEGER_CST: | |
1228 | break; | |
1229 | ||
1230 | default: | |
1231 | return NULL_TREE; | |
1232 | } | |
1233 | ||
faaf1436 RG |
1234 | /* Fold read from constant string. */ |
1235 | if (TREE_CODE (ctor) == STRING_CST) | |
1236 | { | |
1237 | if ((TYPE_MODE (TREE_TYPE (t)) | |
1238 | == TYPE_MODE (TREE_TYPE (TREE_TYPE (ctor)))) | |
1239 | && (GET_MODE_CLASS (TYPE_MODE (TREE_TYPE (TREE_TYPE (ctor)))) | |
1240 | == MODE_INT) | |
1241 | && GET_MODE_SIZE (TYPE_MODE (TREE_TYPE (TREE_TYPE (ctor)))) == 1 | |
1242 | && compare_tree_int (idx, TREE_STRING_LENGTH (ctor)) < 0) | |
0c4d4efb DJ |
1243 | return build_int_cst_type (TREE_TYPE (t), |
1244 | (TREE_STRING_POINTER (ctor) | |
1245 | [TREE_INT_CST_LOW (idx)])); | |
faaf1436 RG |
1246 | return NULL_TREE; |
1247 | } | |
1248 | ||
ae3df618 | 1249 | /* Whoo-hoo! I'll fold ya baby. Yeah! */ |
4038c495 GB |
1250 | FOR_EACH_CONSTRUCTOR_ELT (CONSTRUCTOR_ELTS (ctor), cnt, cfield, cval) |
1251 | if (tree_int_cst_equal (cfield, idx)) | |
62bc00e2 RG |
1252 | { |
1253 | STRIP_USELESS_TYPE_CONVERSION (cval); | |
75ccc1e7 RG |
1254 | if (TREE_CODE (cval) == ADDR_EXPR) |
1255 | { | |
1256 | tree base = get_base_address (TREE_OPERAND (cval, 0)); | |
1257 | if (base && TREE_CODE (base) == VAR_DECL) | |
1258 | add_referenced_var (base); | |
1259 | } | |
62bc00e2 RG |
1260 | return cval; |
1261 | } | |
ae3df618 SB |
1262 | break; |
1263 | ||
1264 | case COMPONENT_REF: | |
1265 | /* Get a CONSTRUCTOR. If BASE is a VAR_DECL, get its | |
1266 | DECL_INITIAL. If BASE is a nested reference into another | |
1267 | ARRAY_REF or COMPONENT_REF, make a recursive call to resolve | |
1268 | the inner reference. */ | |
1269 | base = TREE_OPERAND (t, 0); | |
1270 | switch (TREE_CODE (base)) | |
1271 | { | |
1272 | case VAR_DECL: | |
1273 | if (!TREE_READONLY (base) | |
1274 | || TREE_CODE (TREE_TYPE (base)) != RECORD_TYPE | |
1275 | || !targetm.binds_local_p (base)) | |
1276 | return NULL_TREE; | |
1277 | ||
1278 | ctor = DECL_INITIAL (base); | |
1279 | break; | |
1280 | ||
1281 | case ARRAY_REF: | |
1282 | case COMPONENT_REF: | |
1283 | ctor = fold_const_aggregate_ref (base); | |
1284 | break; | |
1285 | ||
1286 | default: | |
1287 | return NULL_TREE; | |
1288 | } | |
1289 | ||
1290 | if (ctor == NULL_TREE | |
1291 | || TREE_CODE (ctor) != CONSTRUCTOR | |
1292 | || !TREE_STATIC (ctor)) | |
1293 | return NULL_TREE; | |
1294 | ||
1295 | field = TREE_OPERAND (t, 1); | |
1296 | ||
4038c495 GB |
1297 | FOR_EACH_CONSTRUCTOR_ELT (CONSTRUCTOR_ELTS (ctor), cnt, cfield, cval) |
1298 | if (cfield == field | |
ae3df618 | 1299 | /* FIXME: Handle bit-fields. */ |
4038c495 | 1300 | && ! DECL_BIT_FIELD (cfield)) |
62bc00e2 RG |
1301 | { |
1302 | STRIP_USELESS_TYPE_CONVERSION (cval); | |
75ccc1e7 RG |
1303 | if (TREE_CODE (cval) == ADDR_EXPR) |
1304 | { | |
1305 | tree base = get_base_address (TREE_OPERAND (cval, 0)); | |
1306 | if (base && TREE_CODE (base) == VAR_DECL) | |
1307 | add_referenced_var (base); | |
1308 | } | |
62bc00e2 RG |
1309 | return cval; |
1310 | } | |
ae3df618 SB |
1311 | break; |
1312 | ||
1ebd8d9a SB |
1313 | case REALPART_EXPR: |
1314 | case IMAGPART_EXPR: | |
1315 | { | |
1316 | tree c = fold_const_aggregate_ref (TREE_OPERAND (t, 0)); | |
1317 | if (c && TREE_CODE (c) == COMPLEX_CST) | |
1318 | return fold_build1 (TREE_CODE (t), TREE_TYPE (t), c); | |
1319 | break; | |
1320 | } | |
87e1e42b RG |
1321 | |
1322 | case INDIRECT_REF: | |
1323 | { | |
1324 | tree base = TREE_OPERAND (t, 0); | |
1325 | if (TREE_CODE (base) == SSA_NAME | |
1326 | && (value = get_value (base)) | |
1327 | && value->lattice_val == CONSTANT | |
1328 | && TREE_CODE (value->value) == ADDR_EXPR) | |
1329 | return fold_const_aggregate_ref (TREE_OPERAND (value->value, 0)); | |
1330 | break; | |
1331 | } | |
1332 | ||
ae3df618 SB |
1333 | default: |
1334 | break; | |
1335 | } | |
1336 | ||
1337 | return NULL_TREE; | |
1338 | } | |
726a989a RB |
1339 | |
1340 | /* Evaluate statement STMT. | |
1341 | Valid only for assignments, calls, conditionals, and switches. */ | |
6de9cd9a | 1342 | |
0bca51f0 | 1343 | static prop_value_t |
726a989a | 1344 | evaluate_stmt (gimple stmt) |
6de9cd9a | 1345 | { |
0bca51f0 | 1346 | prop_value_t val; |
faaf1436 | 1347 | tree simplified = NULL_TREE; |
0bca51f0 | 1348 | ccp_lattice_t likelyvalue = likely_value (stmt); |
6ac01510 | 1349 | bool is_constant; |
0bca51f0 | 1350 | |
6ac01510 ILT |
1351 | fold_defer_overflow_warnings (); |
1352 | ||
6de9cd9a DN |
1353 | /* If the statement is likely to have a CONSTANT result, then try |
1354 | to fold the statement to determine the constant value. */ | |
726a989a RB |
1355 | /* FIXME. This is the only place that we call ccp_fold. |
1356 | Since likely_value never returns CONSTANT for calls, we will | |
1357 | not attempt to fold them, including builtins that may profit. */ | |
6de9cd9a DN |
1358 | if (likelyvalue == CONSTANT) |
1359 | simplified = ccp_fold (stmt); | |
1360 | /* If the statement is likely to have a VARYING result, then do not | |
1361 | bother folding the statement. */ | |
87e1e42b | 1362 | else if (likelyvalue == VARYING) |
726a989a | 1363 | { |
e0c68ce9 | 1364 | enum gimple_code code = gimple_code (stmt); |
726a989a RB |
1365 | if (code == GIMPLE_ASSIGN) |
1366 | { | |
1367 | enum tree_code subcode = gimple_assign_rhs_code (stmt); | |
1368 | ||
1369 | /* Other cases cannot satisfy is_gimple_min_invariant | |
1370 | without folding. */ | |
1371 | if (get_gimple_rhs_class (subcode) == GIMPLE_SINGLE_RHS) | |
1372 | simplified = gimple_assign_rhs1 (stmt); | |
1373 | } | |
1374 | else if (code == GIMPLE_SWITCH) | |
1375 | simplified = gimple_switch_index (stmt); | |
1376 | else | |
1377 | /* These cannot satisfy is_gimple_min_invariant without folding. */ | |
1378 | gcc_assert (code == GIMPLE_CALL || code == GIMPLE_COND); | |
1379 | } | |
6de9cd9a | 1380 | |
6ac01510 ILT |
1381 | is_constant = simplified && is_gimple_min_invariant (simplified); |
1382 | ||
1383 | fold_undefer_overflow_warnings (is_constant, stmt, 0); | |
1384 | ||
00d382a8 RG |
1385 | if (dump_file && (dump_flags & TDF_DETAILS)) |
1386 | { | |
1387 | fprintf (dump_file, "which is likely "); | |
1388 | switch (likelyvalue) | |
1389 | { | |
1390 | case CONSTANT: | |
1391 | fprintf (dump_file, "CONSTANT"); | |
1392 | break; | |
1393 | case UNDEFINED: | |
1394 | fprintf (dump_file, "UNDEFINED"); | |
1395 | break; | |
1396 | case VARYING: | |
1397 | fprintf (dump_file, "VARYING"); | |
1398 | break; | |
1399 | default:; | |
1400 | } | |
1401 | fprintf (dump_file, "\n"); | |
1402 | } | |
1403 | ||
6ac01510 | 1404 | if (is_constant) |
6de9cd9a DN |
1405 | { |
1406 | /* The statement produced a constant value. */ | |
1407 | val.lattice_val = CONSTANT; | |
0bca51f0 | 1408 | val.value = simplified; |
6de9cd9a DN |
1409 | } |
1410 | else | |
1411 | { | |
1412 | /* The statement produced a nonconstant value. If the statement | |
0bca51f0 DN |
1413 | had UNDEFINED operands, then the result of the statement |
1414 | should be UNDEFINED. Otherwise, the statement is VARYING. */ | |
106dec71 | 1415 | if (likelyvalue == UNDEFINED) |
a318e3ac SB |
1416 | val.lattice_val = likelyvalue; |
1417 | else | |
1418 | val.lattice_val = VARYING; | |
1419 | ||
0bca51f0 | 1420 | val.value = NULL_TREE; |
6de9cd9a | 1421 | } |
750628d8 DN |
1422 | |
1423 | return val; | |
6de9cd9a DN |
1424 | } |
1425 | ||
750628d8 | 1426 | /* Visit the assignment statement STMT. Set the value of its LHS to the |
0bca51f0 DN |
1427 | value computed by the RHS and store LHS in *OUTPUT_P. If STMT |
1428 | creates virtual definitions, set the value of each new name to that | |
726a989a RB |
1429 | of the RHS (if we can derive a constant out of the RHS). |
1430 | Value-returning call statements also perform an assignment, and | |
1431 | are handled here. */ | |
6de9cd9a | 1432 | |
750628d8 | 1433 | static enum ssa_prop_result |
726a989a | 1434 | visit_assignment (gimple stmt, tree *output_p) |
6de9cd9a | 1435 | { |
0bca51f0 | 1436 | prop_value_t val; |
0bca51f0 | 1437 | enum ssa_prop_result retval; |
6de9cd9a | 1438 | |
726a989a | 1439 | tree lhs = gimple_get_lhs (stmt); |
6de9cd9a | 1440 | |
726a989a RB |
1441 | gcc_assert (gimple_code (stmt) != GIMPLE_CALL |
1442 | || gimple_call_lhs (stmt) != NULL_TREE); | |
1443 | ||
1444 | if (gimple_assign_copy_p (stmt)) | |
750628d8 | 1445 | { |
726a989a | 1446 | tree rhs = gimple_assign_rhs1 (stmt); |
0bca51f0 | 1447 | |
726a989a RB |
1448 | if (TREE_CODE (rhs) == SSA_NAME) |
1449 | { | |
1450 | /* For a simple copy operation, we copy the lattice values. */ | |
1451 | prop_value_t *nval = get_value (rhs); | |
1452 | val = *nval; | |
1453 | } | |
0bca51f0 | 1454 | else |
726a989a | 1455 | val = evaluate_stmt (stmt); |
750628d8 DN |
1456 | } |
1457 | else | |
726a989a RB |
1458 | /* Evaluate the statement, which could be |
1459 | either a GIMPLE_ASSIGN or a GIMPLE_CALL. */ | |
87e1e42b | 1460 | val = evaluate_stmt (stmt); |
6de9cd9a | 1461 | |
0bca51f0 | 1462 | retval = SSA_PROP_NOT_INTERESTING; |
6de9cd9a | 1463 | |
750628d8 | 1464 | /* Set the lattice value of the statement's output. */ |
0bca51f0 | 1465 | if (TREE_CODE (lhs) == SSA_NAME) |
6de9cd9a | 1466 | { |
0bca51f0 DN |
1467 | /* If STMT is an assignment to an SSA_NAME, we only have one |
1468 | value to set. */ | |
1469 | if (set_lattice_value (lhs, val)) | |
1470 | { | |
1471 | *output_p = lhs; | |
1472 | if (val.lattice_val == VARYING) | |
1473 | retval = SSA_PROP_VARYING; | |
1474 | else | |
1475 | retval = SSA_PROP_INTERESTING; | |
1476 | } | |
6de9cd9a | 1477 | } |
0bca51f0 DN |
1478 | |
1479 | return retval; | |
6de9cd9a DN |
1480 | } |
1481 | ||
6de9cd9a | 1482 | |
750628d8 DN |
1483 | /* Visit the conditional statement STMT. Return SSA_PROP_INTERESTING |
1484 | if it can determine which edge will be taken. Otherwise, return | |
1485 | SSA_PROP_VARYING. */ | |
1486 | ||
1487 | static enum ssa_prop_result | |
726a989a | 1488 | visit_cond_stmt (gimple stmt, edge *taken_edge_p) |
6de9cd9a | 1489 | { |
0bca51f0 | 1490 | prop_value_t val; |
750628d8 DN |
1491 | basic_block block; |
1492 | ||
726a989a | 1493 | block = gimple_bb (stmt); |
750628d8 DN |
1494 | val = evaluate_stmt (stmt); |
1495 | ||
1496 | /* Find which edge out of the conditional block will be taken and add it | |
1497 | to the worklist. If no single edge can be determined statically, | |
1498 | return SSA_PROP_VARYING to feed all the outgoing edges to the | |
1499 | propagation engine. */ | |
0bca51f0 | 1500 | *taken_edge_p = val.value ? find_taken_edge (block, val.value) : 0; |
750628d8 DN |
1501 | if (*taken_edge_p) |
1502 | return SSA_PROP_INTERESTING; | |
1503 | else | |
1504 | return SSA_PROP_VARYING; | |
6de9cd9a DN |
1505 | } |
1506 | ||
6de9cd9a | 1507 | |
750628d8 DN |
1508 | /* Evaluate statement STMT. If the statement produces an output value and |
1509 | its evaluation changes the lattice value of its output, return | |
1510 | SSA_PROP_INTERESTING and set *OUTPUT_P to the SSA_NAME holding the | |
1511 | output value. | |
1512 | ||
1513 | If STMT is a conditional branch and we can determine its truth | |
1514 | value, set *TAKEN_EDGE_P accordingly. If STMT produces a varying | |
1515 | value, return SSA_PROP_VARYING. */ | |
6de9cd9a | 1516 | |
750628d8 | 1517 | static enum ssa_prop_result |
726a989a | 1518 | ccp_visit_stmt (gimple stmt, edge *taken_edge_p, tree *output_p) |
750628d8 | 1519 | { |
750628d8 DN |
1520 | tree def; |
1521 | ssa_op_iter iter; | |
6de9cd9a | 1522 | |
750628d8 | 1523 | if (dump_file && (dump_flags & TDF_DETAILS)) |
6de9cd9a | 1524 | { |
0bca51f0 | 1525 | fprintf (dump_file, "\nVisiting statement:\n"); |
726a989a | 1526 | print_gimple_stmt (dump_file, stmt, 0, dump_flags); |
6de9cd9a | 1527 | } |
6de9cd9a | 1528 | |
726a989a | 1529 | switch (gimple_code (stmt)) |
6de9cd9a | 1530 | { |
726a989a RB |
1531 | case GIMPLE_ASSIGN: |
1532 | /* If the statement is an assignment that produces a single | |
1533 | output value, evaluate its RHS to see if the lattice value of | |
1534 | its output has changed. */ | |
1535 | return visit_assignment (stmt, output_p); | |
1536 | ||
1537 | case GIMPLE_CALL: | |
1538 | /* A value-returning call also performs an assignment. */ | |
1539 | if (gimple_call_lhs (stmt) != NULL_TREE) | |
1540 | return visit_assignment (stmt, output_p); | |
1541 | break; | |
1542 | ||
1543 | case GIMPLE_COND: | |
1544 | case GIMPLE_SWITCH: | |
1545 | /* If STMT is a conditional branch, see if we can determine | |
1546 | which branch will be taken. */ | |
1547 | /* FIXME. It appears that we should be able to optimize | |
1548 | computed GOTOs here as well. */ | |
1549 | return visit_cond_stmt (stmt, taken_edge_p); | |
1550 | ||
1551 | default: | |
1552 | break; | |
6de9cd9a | 1553 | } |
6de9cd9a | 1554 | |
750628d8 DN |
1555 | /* Any other kind of statement is not interesting for constant |
1556 | propagation and, therefore, not worth simulating. */ | |
750628d8 DN |
1557 | if (dump_file && (dump_flags & TDF_DETAILS)) |
1558 | fprintf (dump_file, "No interesting values produced. Marked VARYING.\n"); | |
6de9cd9a | 1559 | |
750628d8 DN |
1560 | /* Definitions made by statements other than assignments to |
1561 | SSA_NAMEs represent unknown modifications to their outputs. | |
1562 | Mark them VARYING. */ | |
0bca51f0 DN |
1563 | FOR_EACH_SSA_TREE_OPERAND (def, stmt, iter, SSA_OP_ALL_DEFS) |
1564 | { | |
dce2b2f6 | 1565 | prop_value_t v = { VARYING, NULL_TREE }; |
0bca51f0 DN |
1566 | set_lattice_value (def, v); |
1567 | } | |
6de9cd9a | 1568 | |
750628d8 DN |
1569 | return SSA_PROP_VARYING; |
1570 | } | |
6de9cd9a | 1571 | |
6de9cd9a | 1572 | |
0bca51f0 | 1573 | /* Main entry point for SSA Conditional Constant Propagation. */ |
750628d8 | 1574 | |
3253eafb | 1575 | static unsigned int |
dce2b2f6 | 1576 | do_ssa_ccp (void) |
750628d8 DN |
1577 | { |
1578 | ccp_initialize (); | |
1579 | ssa_propagate (ccp_visit_stmt, ccp_visit_phi_node); | |
3253eafb | 1580 | if (ccp_finalize ()) |
706ca88e | 1581 | return (TODO_cleanup_cfg | TODO_update_ssa | TODO_remove_unused_locals); |
3253eafb JH |
1582 | else |
1583 | return 0; | |
6de9cd9a DN |
1584 | } |
1585 | ||
173b818d BB |
1586 | |
1587 | static bool | |
750628d8 | 1588 | gate_ccp (void) |
173b818d | 1589 | { |
750628d8 | 1590 | return flag_tree_ccp != 0; |
173b818d BB |
1591 | } |
1592 | ||
6de9cd9a | 1593 | |
8ddbbcae | 1594 | struct gimple_opt_pass pass_ccp = |
750628d8 | 1595 | { |
8ddbbcae JH |
1596 | { |
1597 | GIMPLE_PASS, | |
750628d8 DN |
1598 | "ccp", /* name */ |
1599 | gate_ccp, /* gate */ | |
0bca51f0 | 1600 | do_ssa_ccp, /* execute */ |
750628d8 DN |
1601 | NULL, /* sub */ |
1602 | NULL, /* next */ | |
1603 | 0, /* static_pass_number */ | |
1604 | TV_TREE_CCP, /* tv_id */ | |
7faade0f | 1605 | PROP_cfg | PROP_ssa, /* properties_required */ |
750628d8 | 1606 | 0, /* properties_provided */ |
ae07b463 | 1607 | 0, /* properties_destroyed */ |
750628d8 | 1608 | 0, /* todo_flags_start */ |
3253eafb | 1609 | TODO_dump_func | TODO_verify_ssa |
8ddbbcae JH |
1610 | | TODO_verify_stmts | TODO_ggc_collect/* todo_flags_finish */ |
1611 | } | |
750628d8 | 1612 | }; |
6de9cd9a | 1613 | |
6de9cd9a | 1614 | |
6de9cd9a DN |
1615 | /* A subroutine of fold_stmt_r. Attempts to fold *(A+O) to A[X]. |
1616 | BASE is an array type. OFFSET is a byte displacement. ORIG_TYPE | |
9cf737f8 | 1617 | is the desired result type. */ |
6de9cd9a DN |
1618 | |
1619 | static tree | |
1fd89060 RG |
1620 | maybe_fold_offset_to_array_ref (tree base, tree offset, tree orig_type, |
1621 | bool allow_negative_idx) | |
6de9cd9a | 1622 | { |
891fc5e9 | 1623 | tree min_idx, idx, idx_type, elt_offset = integer_zero_node; |
44de5aeb | 1624 | tree array_type, elt_type, elt_size; |
3097760b | 1625 | tree domain_type; |
44de5aeb RK |
1626 | |
1627 | /* If BASE is an ARRAY_REF, we can pick up another offset (this time | |
1628 | measured in units of the size of elements type) from that ARRAY_REF). | |
1629 | We can't do anything if either is variable. | |
1630 | ||
1631 | The case we handle here is *(&A[N]+O). */ | |
1632 | if (TREE_CODE (base) == ARRAY_REF) | |
1633 | { | |
1634 | tree low_bound = array_ref_low_bound (base); | |
1635 | ||
1636 | elt_offset = TREE_OPERAND (base, 1); | |
1637 | if (TREE_CODE (low_bound) != INTEGER_CST | |
1638 | || TREE_CODE (elt_offset) != INTEGER_CST) | |
1639 | return NULL_TREE; | |
1640 | ||
1641 | elt_offset = int_const_binop (MINUS_EXPR, elt_offset, low_bound, 0); | |
1642 | base = TREE_OPERAND (base, 0); | |
1643 | } | |
6de9cd9a DN |
1644 | |
1645 | /* Ignore stupid user tricks of indexing non-array variables. */ | |
1646 | array_type = TREE_TYPE (base); | |
1647 | if (TREE_CODE (array_type) != ARRAY_TYPE) | |
1648 | return NULL_TREE; | |
1649 | elt_type = TREE_TYPE (array_type); | |
f4088621 | 1650 | if (!useless_type_conversion_p (orig_type, elt_type)) |
6de9cd9a | 1651 | return NULL_TREE; |
891fc5e9 RG |
1652 | |
1653 | /* Use signed size type for intermediate computation on the index. */ | |
1654 | idx_type = signed_type_for (size_type_node); | |
1655 | ||
44de5aeb RK |
1656 | /* If OFFSET and ELT_OFFSET are zero, we don't care about the size of the |
1657 | element type (so we can use the alignment if it's not constant). | |
1658 | Otherwise, compute the offset as an index by using a division. If the | |
1659 | division isn't exact, then don't do anything. */ | |
6de9cd9a | 1660 | elt_size = TYPE_SIZE_UNIT (elt_type); |
fe9821b8 JH |
1661 | if (!elt_size) |
1662 | return NULL; | |
44de5aeb RK |
1663 | if (integer_zerop (offset)) |
1664 | { | |
1665 | if (TREE_CODE (elt_size) != INTEGER_CST) | |
1666 | elt_size = size_int (TYPE_ALIGN (elt_type)); | |
6de9cd9a | 1667 | |
891fc5e9 | 1668 | idx = build_int_cst (idx_type, 0); |
44de5aeb RK |
1669 | } |
1670 | else | |
1671 | { | |
1672 | unsigned HOST_WIDE_INT lquo, lrem; | |
1673 | HOST_WIDE_INT hquo, hrem; | |
891fc5e9 | 1674 | double_int soffset; |
44de5aeb | 1675 | |
891fc5e9 RG |
1676 | /* The final array offset should be signed, so we need |
1677 | to sign-extend the (possibly pointer) offset here | |
1678 | and use signed division. */ | |
1679 | soffset = double_int_sext (tree_to_double_int (offset), | |
1680 | TYPE_PRECISION (TREE_TYPE (offset))); | |
44de5aeb | 1681 | if (TREE_CODE (elt_size) != INTEGER_CST |
891fc5e9 RG |
1682 | || div_and_round_double (TRUNC_DIV_EXPR, 0, |
1683 | soffset.low, soffset.high, | |
44de5aeb RK |
1684 | TREE_INT_CST_LOW (elt_size), |
1685 | TREE_INT_CST_HIGH (elt_size), | |
1686 | &lquo, &hquo, &lrem, &hrem) | |
1687 | || lrem || hrem) | |
1688 | return NULL_TREE; | |
6de9cd9a | 1689 | |
891fc5e9 | 1690 | idx = build_int_cst_wide (idx_type, lquo, hquo); |
44de5aeb RK |
1691 | } |
1692 | ||
1693 | /* Assume the low bound is zero. If there is a domain type, get the | |
1694 | low bound, if any, convert the index into that type, and add the | |
1695 | low bound. */ | |
891fc5e9 | 1696 | min_idx = build_int_cst (idx_type, 0); |
3097760b JH |
1697 | domain_type = TYPE_DOMAIN (array_type); |
1698 | if (domain_type) | |
6de9cd9a | 1699 | { |
3097760b | 1700 | idx_type = domain_type; |
891fc5e9 RG |
1701 | if (TYPE_MIN_VALUE (idx_type)) |
1702 | min_idx = TYPE_MIN_VALUE (idx_type); | |
44de5aeb | 1703 | else |
891fc5e9 | 1704 | min_idx = fold_convert (idx_type, min_idx); |
44de5aeb RK |
1705 | |
1706 | if (TREE_CODE (min_idx) != INTEGER_CST) | |
1707 | return NULL_TREE; | |
1708 | ||
891fc5e9 | 1709 | elt_offset = fold_convert (idx_type, elt_offset); |
6de9cd9a DN |
1710 | } |
1711 | ||
44de5aeb RK |
1712 | if (!integer_zerop (min_idx)) |
1713 | idx = int_const_binop (PLUS_EXPR, idx, min_idx, 0); | |
1714 | if (!integer_zerop (elt_offset)) | |
1715 | idx = int_const_binop (PLUS_EXPR, idx, elt_offset, 0); | |
1716 | ||
891fc5e9 RG |
1717 | /* Make sure to possibly truncate late after offsetting. */ |
1718 | idx = fold_convert (idx_type, idx); | |
1719 | ||
3097760b | 1720 | /* We don't want to construct access past array bounds. For example |
1fd89060 RG |
1721 | char *(c[4]); |
1722 | c[3][2]; | |
1723 | should not be simplified into (*c)[14] or tree-vrp will | |
1724 | give false warnings. The same is true for | |
1725 | struct A { long x; char d[0]; } *a; | |
1726 | (char *)a - 4; | |
1727 | which should be not folded to &a->d[-8]. */ | |
1728 | if (domain_type | |
1729 | && TYPE_MAX_VALUE (domain_type) | |
3097760b JH |
1730 | && TREE_CODE (TYPE_MAX_VALUE (domain_type)) == INTEGER_CST) |
1731 | { | |
1732 | tree up_bound = TYPE_MAX_VALUE (domain_type); | |
1733 | ||
1734 | if (tree_int_cst_lt (up_bound, idx) | |
1735 | /* Accesses after the end of arrays of size 0 (gcc | |
1736 | extension) and 1 are likely intentional ("struct | |
1737 | hack"). */ | |
1738 | && compare_tree_int (up_bound, 1) > 0) | |
1739 | return NULL_TREE; | |
1740 | } | |
1fd89060 RG |
1741 | if (domain_type |
1742 | && TYPE_MIN_VALUE (domain_type)) | |
1743 | { | |
1744 | if (!allow_negative_idx | |
1745 | && TREE_CODE (TYPE_MIN_VALUE (domain_type)) == INTEGER_CST | |
1746 | && tree_int_cst_lt (idx, TYPE_MIN_VALUE (domain_type))) | |
1747 | return NULL_TREE; | |
1748 | } | |
1749 | else if (!allow_negative_idx | |
1750 | && compare_tree_int (idx, 0) < 0) | |
1751 | return NULL_TREE; | |
3097760b | 1752 | |
04d86531 | 1753 | return build4 (ARRAY_REF, elt_type, base, idx, NULL_TREE, NULL_TREE); |
6de9cd9a DN |
1754 | } |
1755 | ||
750628d8 | 1756 | |
fe9821b8 | 1757 | /* Attempt to fold *(S+O) to S.X. |
6de9cd9a DN |
1758 | BASE is a record type. OFFSET is a byte displacement. ORIG_TYPE |
1759 | is the desired result type. */ | |
6de9cd9a | 1760 | |
fe9821b8 | 1761 | static tree |
6de9cd9a DN |
1762 | maybe_fold_offset_to_component_ref (tree record_type, tree base, tree offset, |
1763 | tree orig_type, bool base_is_ptr) | |
1764 | { | |
f34fa464 | 1765 | tree f, t, field_type, tail_array_field, field_offset; |
6e6e19cb JH |
1766 | tree ret; |
1767 | tree new_base; | |
6de9cd9a DN |
1768 | |
1769 | if (TREE_CODE (record_type) != RECORD_TYPE | |
1770 | && TREE_CODE (record_type) != UNION_TYPE | |
1771 | && TREE_CODE (record_type) != QUAL_UNION_TYPE) | |
1772 | return NULL_TREE; | |
1773 | ||
1774 | /* Short-circuit silly cases. */ | |
f4088621 | 1775 | if (useless_type_conversion_p (record_type, orig_type)) |
6de9cd9a DN |
1776 | return NULL_TREE; |
1777 | ||
1778 | tail_array_field = NULL_TREE; | |
1779 | for (f = TYPE_FIELDS (record_type); f ; f = TREE_CHAIN (f)) | |
1780 | { | |
1781 | int cmp; | |
1782 | ||
1783 | if (TREE_CODE (f) != FIELD_DECL) | |
1784 | continue; | |
1785 | if (DECL_BIT_FIELD (f)) | |
1786 | continue; | |
f34fa464 | 1787 | |
fe9821b8 JH |
1788 | if (!DECL_FIELD_OFFSET (f)) |
1789 | continue; | |
f34fa464 ZD |
1790 | field_offset = byte_position (f); |
1791 | if (TREE_CODE (field_offset) != INTEGER_CST) | |
6de9cd9a DN |
1792 | continue; |
1793 | ||
1794 | /* ??? Java creates "interesting" fields for representing base classes. | |
1795 | They have no name, and have no context. With no context, we get into | |
1796 | trouble with nonoverlapping_component_refs_p. Skip them. */ | |
1797 | if (!DECL_FIELD_CONTEXT (f)) | |
1798 | continue; | |
1799 | ||
1800 | /* The previous array field isn't at the end. */ | |
1801 | tail_array_field = NULL_TREE; | |
1802 | ||
1803 | /* Check to see if this offset overlaps with the field. */ | |
f34fa464 | 1804 | cmp = tree_int_cst_compare (field_offset, offset); |
6de9cd9a DN |
1805 | if (cmp > 0) |
1806 | continue; | |
1807 | ||
1808 | field_type = TREE_TYPE (f); | |
6de9cd9a DN |
1809 | |
1810 | /* Here we exactly match the offset being checked. If the types match, | |
1811 | then we can return that field. */ | |
53dba802 | 1812 | if (cmp == 0 |
f4088621 | 1813 | && useless_type_conversion_p (orig_type, field_type)) |
6de9cd9a DN |
1814 | { |
1815 | if (base_is_ptr) | |
1816 | base = build1 (INDIRECT_REF, record_type, base); | |
b4257cfc | 1817 | t = build3 (COMPONENT_REF, field_type, base, f, NULL_TREE); |
6de9cd9a DN |
1818 | return t; |
1819 | } | |
53dba802 ZD |
1820 | |
1821 | /* Don't care about offsets into the middle of scalars. */ | |
1822 | if (!AGGREGATE_TYPE_P (field_type)) | |
1823 | continue; | |
6de9cd9a | 1824 | |
53dba802 ZD |
1825 | /* Check for array at the end of the struct. This is often |
1826 | used as for flexible array members. We should be able to | |
1827 | turn this into an array access anyway. */ | |
1828 | if (TREE_CODE (field_type) == ARRAY_TYPE) | |
1829 | tail_array_field = f; | |
1830 | ||
1831 | /* Check the end of the field against the offset. */ | |
1832 | if (!DECL_SIZE_UNIT (f) | |
1833 | || TREE_CODE (DECL_SIZE_UNIT (f)) != INTEGER_CST) | |
1834 | continue; | |
1835 | t = int_const_binop (MINUS_EXPR, offset, field_offset, 1); | |
1836 | if (!tree_int_cst_lt (t, DECL_SIZE_UNIT (f))) | |
1837 | continue; | |
6de9cd9a | 1838 | |
53dba802 ZD |
1839 | /* If we matched, then set offset to the displacement into |
1840 | this field. */ | |
6e6e19cb JH |
1841 | if (base_is_ptr) |
1842 | new_base = build1 (INDIRECT_REF, record_type, base); | |
1843 | else | |
1844 | new_base = base; | |
1845 | new_base = build3 (COMPONENT_REF, field_type, new_base, f, NULL_TREE); | |
1846 | ||
1847 | /* Recurse to possibly find the match. */ | |
1fd89060 RG |
1848 | ret = maybe_fold_offset_to_array_ref (new_base, t, orig_type, |
1849 | f == TYPE_FIELDS (record_type)); | |
6e6e19cb JH |
1850 | if (ret) |
1851 | return ret; | |
1852 | ret = maybe_fold_offset_to_component_ref (field_type, new_base, t, | |
1853 | orig_type, false); | |
1854 | if (ret) | |
1855 | return ret; | |
6de9cd9a DN |
1856 | } |
1857 | ||
1858 | if (!tail_array_field) | |
1859 | return NULL_TREE; | |
1860 | ||
1861 | f = tail_array_field; | |
1862 | field_type = TREE_TYPE (f); | |
53dba802 | 1863 | offset = int_const_binop (MINUS_EXPR, offset, byte_position (f), 1); |
6de9cd9a | 1864 | |
6de9cd9a | 1865 | /* If we get here, we've got an aggregate field, and a possibly |
1ea7e6ad | 1866 | nonzero offset into them. Recurse and hope for a valid match. */ |
6de9cd9a DN |
1867 | if (base_is_ptr) |
1868 | base = build1 (INDIRECT_REF, record_type, base); | |
b4257cfc | 1869 | base = build3 (COMPONENT_REF, field_type, base, f, NULL_TREE); |
6de9cd9a | 1870 | |
1fd89060 RG |
1871 | t = maybe_fold_offset_to_array_ref (base, offset, orig_type, |
1872 | f == TYPE_FIELDS (record_type)); | |
6de9cd9a DN |
1873 | if (t) |
1874 | return t; | |
1875 | return maybe_fold_offset_to_component_ref (field_type, base, offset, | |
1876 | orig_type, false); | |
1877 | } | |
1878 | ||
fe9821b8 JH |
1879 | /* Attempt to express (ORIG_TYPE)BASE+OFFSET as BASE->field_of_orig_type |
1880 | or BASE[index] or by combination of those. | |
1881 | ||
1882 | Before attempting the conversion strip off existing ADDR_EXPRs and | |
1883 | handled component refs. */ | |
1884 | ||
1885 | tree | |
1886 | maybe_fold_offset_to_reference (tree base, tree offset, tree orig_type) | |
1887 | { | |
1888 | tree ret; | |
1889 | tree type; | |
1890 | bool base_is_ptr = true; | |
1891 | ||
1892 | STRIP_NOPS (base); | |
1893 | if (TREE_CODE (base) == ADDR_EXPR) | |
1894 | { | |
1895 | base_is_ptr = false; | |
1896 | ||
1897 | base = TREE_OPERAND (base, 0); | |
1898 | ||
1899 | /* Handle case where existing COMPONENT_REF pick e.g. wrong field of union, | |
1900 | so it needs to be removed and new COMPONENT_REF constructed. | |
1901 | The wrong COMPONENT_REF are often constructed by folding the | |
1902 | (type *)&object within the expression (type *)&object+offset */ | |
99f536cc | 1903 | if (handled_component_p (base)) |
fe9821b8 JH |
1904 | { |
1905 | HOST_WIDE_INT sub_offset, size, maxsize; | |
1906 | tree newbase; | |
1907 | newbase = get_ref_base_and_extent (base, &sub_offset, | |
1908 | &size, &maxsize); | |
1909 | gcc_assert (newbase); | |
99f536cc | 1910 | if (size == maxsize |
a214f4d6 | 1911 | && size != -1 |
99f536cc | 1912 | && !(sub_offset & (BITS_PER_UNIT - 1))) |
fe9821b8 JH |
1913 | { |
1914 | base = newbase; | |
1915 | if (sub_offset) | |
1916 | offset = int_const_binop (PLUS_EXPR, offset, | |
1917 | build_int_cst (TREE_TYPE (offset), | |
1918 | sub_offset / BITS_PER_UNIT), 1); | |
1919 | } | |
1920 | } | |
f4088621 | 1921 | if (useless_type_conversion_p (orig_type, TREE_TYPE (base)) |
fe9821b8 JH |
1922 | && integer_zerop (offset)) |
1923 | return base; | |
1924 | type = TREE_TYPE (base); | |
1925 | } | |
1926 | else | |
1927 | { | |
1928 | base_is_ptr = true; | |
1929 | if (!POINTER_TYPE_P (TREE_TYPE (base))) | |
1930 | return NULL_TREE; | |
1931 | type = TREE_TYPE (TREE_TYPE (base)); | |
1932 | } | |
1933 | ret = maybe_fold_offset_to_component_ref (type, base, offset, | |
1934 | orig_type, base_is_ptr); | |
1935 | if (!ret) | |
1936 | { | |
1937 | if (base_is_ptr) | |
1938 | base = build1 (INDIRECT_REF, type, base); | |
1fd89060 | 1939 | ret = maybe_fold_offset_to_array_ref (base, offset, orig_type, true); |
fe9821b8 JH |
1940 | } |
1941 | return ret; | |
1942 | } | |
750628d8 | 1943 | |
99f536cc RG |
1944 | /* Attempt to express (ORIG_TYPE)&BASE+OFFSET as &BASE->field_of_orig_type |
1945 | or &BASE[index] or by combination of those. | |
1946 | ||
1947 | Before attempting the conversion strip off existing component refs. */ | |
1948 | ||
1949 | tree | |
1950 | maybe_fold_offset_to_address (tree addr, tree offset, tree orig_type) | |
1951 | { | |
1952 | tree t; | |
1953 | ||
1954 | gcc_assert (POINTER_TYPE_P (TREE_TYPE (addr)) | |
1955 | && POINTER_TYPE_P (orig_type)); | |
1956 | ||
1957 | t = maybe_fold_offset_to_reference (addr, offset, TREE_TYPE (orig_type)); | |
1958 | if (t != NULL_TREE) | |
1959 | { | |
1960 | tree orig = addr; | |
1961 | tree ptr_type; | |
1962 | ||
1963 | /* For __builtin_object_size to function correctly we need to | |
1964 | make sure not to fold address arithmetic so that we change | |
1965 | reference from one array to another. This would happen for | |
1966 | example for | |
1967 | ||
1968 | struct X { char s1[10]; char s2[10] } s; | |
1969 | char *foo (void) { return &s.s2[-4]; } | |
1970 | ||
1971 | where we need to avoid generating &s.s1[6]. As the C and | |
1972 | C++ frontends create different initial trees | |
1973 | (char *) &s.s1 + -4 vs. &s.s1[-4] we have to do some | |
1974 | sophisticated comparisons here. Note that checking for the | |
1975 | condition after the fact is easier than trying to avoid doing | |
1976 | the folding. */ | |
1977 | STRIP_NOPS (orig); | |
1978 | if (TREE_CODE (orig) == ADDR_EXPR) | |
1979 | orig = TREE_OPERAND (orig, 0); | |
1980 | if ((TREE_CODE (orig) == ARRAY_REF | |
1981 | || (TREE_CODE (orig) == COMPONENT_REF | |
1982 | && TREE_CODE (TREE_TYPE (TREE_OPERAND (orig, 1))) == ARRAY_TYPE)) | |
1983 | && (TREE_CODE (t) == ARRAY_REF | |
f07049c8 | 1984 | || TREE_CODE (t) == COMPONENT_REF) |
99f536cc RG |
1985 | && !operand_equal_p (TREE_CODE (orig) == ARRAY_REF |
1986 | ? TREE_OPERAND (orig, 0) : orig, | |
1987 | TREE_CODE (t) == ARRAY_REF | |
1988 | ? TREE_OPERAND (t, 0) : t, 0)) | |
1989 | return NULL_TREE; | |
1990 | ||
1991 | ptr_type = build_pointer_type (TREE_TYPE (t)); | |
1992 | if (!useless_type_conversion_p (orig_type, ptr_type)) | |
1993 | return NULL_TREE; | |
1994 | return build_fold_addr_expr_with_type (t, ptr_type); | |
1995 | } | |
1996 | ||
1997 | return NULL_TREE; | |
1998 | } | |
1999 | ||
6de9cd9a DN |
2000 | /* A subroutine of fold_stmt_r. Attempt to simplify *(BASE+OFFSET). |
2001 | Return the simplified expression, or NULL if nothing could be done. */ | |
2002 | ||
2003 | static tree | |
2004 | maybe_fold_stmt_indirect (tree expr, tree base, tree offset) | |
2005 | { | |
2006 | tree t; | |
cbf8d355 | 2007 | bool volatile_p = TREE_THIS_VOLATILE (expr); |
6de9cd9a DN |
2008 | |
2009 | /* We may well have constructed a double-nested PLUS_EXPR via multiple | |
2010 | substitutions. Fold that down to one. Remove NON_LVALUE_EXPRs that | |
2011 | are sometimes added. */ | |
2012 | base = fold (base); | |
ff7c8597 | 2013 | STRIP_TYPE_NOPS (base); |
6de9cd9a DN |
2014 | TREE_OPERAND (expr, 0) = base; |
2015 | ||
2016 | /* One possibility is that the address reduces to a string constant. */ | |
2017 | t = fold_read_from_constant_string (expr); | |
2018 | if (t) | |
2019 | return t; | |
2020 | ||
5be014d5 AP |
2021 | /* Add in any offset from a POINTER_PLUS_EXPR. */ |
2022 | if (TREE_CODE (base) == POINTER_PLUS_EXPR) | |
6de9cd9a DN |
2023 | { |
2024 | tree offset2; | |
2025 | ||
2026 | offset2 = TREE_OPERAND (base, 1); | |
2027 | if (TREE_CODE (offset2) != INTEGER_CST) | |
2028 | return NULL_TREE; | |
2029 | base = TREE_OPERAND (base, 0); | |
2030 | ||
5be014d5 AP |
2031 | offset = fold_convert (sizetype, |
2032 | int_const_binop (PLUS_EXPR, offset, offset2, 1)); | |
6de9cd9a DN |
2033 | } |
2034 | ||
2035 | if (TREE_CODE (base) == ADDR_EXPR) | |
2036 | { | |
fe9821b8 JH |
2037 | tree base_addr = base; |
2038 | ||
6de9cd9a DN |
2039 | /* Strip the ADDR_EXPR. */ |
2040 | base = TREE_OPERAND (base, 0); | |
2041 | ||
0534fa56 RH |
2042 | /* Fold away CONST_DECL to its value, if the type is scalar. */ |
2043 | if (TREE_CODE (base) == CONST_DECL | |
1b738915 | 2044 | && is_gimple_min_invariant (DECL_INITIAL (base))) |
0534fa56 RH |
2045 | return DECL_INITIAL (base); |
2046 | ||
6de9cd9a | 2047 | /* Try folding *(&B+O) to B.X. */ |
fe9821b8 JH |
2048 | t = maybe_fold_offset_to_reference (base_addr, offset, |
2049 | TREE_TYPE (expr)); | |
6de9cd9a | 2050 | if (t) |
cbf8d355 | 2051 | { |
e2104f59 RG |
2052 | /* Preserve volatileness of the original expression. |
2053 | We can end up with a plain decl here which is shared | |
2054 | and we shouldn't mess with its flags. */ | |
2055 | if (!SSA_VAR_P (t)) | |
2056 | TREE_THIS_VOLATILE (t) = volatile_p; | |
cbf8d355 RG |
2057 | return t; |
2058 | } | |
6de9cd9a DN |
2059 | } |
2060 | else | |
2061 | { | |
2062 | /* We can get here for out-of-range string constant accesses, | |
2063 | such as "_"[3]. Bail out of the entire substitution search | |
2064 | and arrange for the entire statement to be replaced by a | |
aabcd309 | 2065 | call to __builtin_trap. In all likelihood this will all be |
6de9cd9a DN |
2066 | constant-folded away, but in the meantime we can't leave with |
2067 | something that get_expr_operands can't understand. */ | |
2068 | ||
2069 | t = base; | |
2070 | STRIP_NOPS (t); | |
2071 | if (TREE_CODE (t) == ADDR_EXPR | |
2072 | && TREE_CODE (TREE_OPERAND (t, 0)) == STRING_CST) | |
2073 | { | |
2074 | /* FIXME: Except that this causes problems elsewhere with dead | |
0e61db61 | 2075 | code not being deleted, and we die in the rtl expanders |
6de9cd9a DN |
2076 | because we failed to remove some ssa_name. In the meantime, |
2077 | just return zero. */ | |
2078 | /* FIXME2: This condition should be signaled by | |
2079 | fold_read_from_constant_string directly, rather than | |
2080 | re-checking for it here. */ | |
2081 | return integer_zero_node; | |
2082 | } | |
2083 | ||
2084 | /* Try folding *(B+O) to B->X. Still an improvement. */ | |
2085 | if (POINTER_TYPE_P (TREE_TYPE (base))) | |
2086 | { | |
fe9821b8 JH |
2087 | t = maybe_fold_offset_to_reference (base, offset, |
2088 | TREE_TYPE (expr)); | |
6de9cd9a DN |
2089 | if (t) |
2090 | return t; | |
2091 | } | |
2092 | } | |
2093 | ||
2094 | /* Otherwise we had an offset that we could not simplify. */ | |
2095 | return NULL_TREE; | |
2096 | } | |
2097 | ||
750628d8 | 2098 | |
726a989a | 2099 | /* A quaint feature extant in our address arithmetic is that there |
6de9cd9a DN |
2100 | can be hidden type changes here. The type of the result need |
2101 | not be the same as the type of the input pointer. | |
2102 | ||
2103 | What we're after here is an expression of the form | |
2104 | (T *)(&array + const) | |
726a989a RB |
2105 | where array is OP0, const is OP1, RES_TYPE is T and |
2106 | the cast doesn't actually exist, but is implicit in the | |
5be014d5 | 2107 | type of the POINTER_PLUS_EXPR. We'd like to turn this into |
6de9cd9a DN |
2108 | &array[x] |
2109 | which may be able to propagate further. */ | |
2110 | ||
726a989a RB |
2111 | tree |
2112 | maybe_fold_stmt_addition (tree res_type, tree op0, tree op1) | |
6de9cd9a | 2113 | { |
6de9cd9a DN |
2114 | tree ptd_type; |
2115 | tree t; | |
6de9cd9a | 2116 | |
6de9cd9a DN |
2117 | /* The first operand should be an ADDR_EXPR. */ |
2118 | if (TREE_CODE (op0) != ADDR_EXPR) | |
2119 | return NULL_TREE; | |
2120 | op0 = TREE_OPERAND (op0, 0); | |
2121 | ||
f76968e6 RG |
2122 | /* It had better be a constant. */ |
2123 | if (TREE_CODE (op1) != INTEGER_CST) | |
2124 | { | |
2125 | /* Or op0 should now be A[0] and the non-constant offset defined | |
2126 | via a multiplication by the array element size. */ | |
2127 | if (TREE_CODE (op0) == ARRAY_REF | |
2128 | && integer_zerop (TREE_OPERAND (op0, 1)) | |
2129 | && TREE_CODE (op1) == SSA_NAME | |
2130 | && host_integerp (TYPE_SIZE_UNIT (TREE_TYPE (op0)), 1)) | |
2131 | { | |
2132 | gimple offset_def = SSA_NAME_DEF_STMT (op1); | |
2133 | if (!is_gimple_assign (offset_def)) | |
2134 | return NULL_TREE; | |
2135 | ||
2136 | if (gimple_assign_rhs_code (offset_def) == MULT_EXPR | |
2137 | && TREE_CODE (gimple_assign_rhs2 (offset_def)) == INTEGER_CST | |
2138 | && tree_int_cst_equal (gimple_assign_rhs2 (offset_def), | |
2139 | TYPE_SIZE_UNIT (TREE_TYPE (op0)))) | |
2140 | return build1 (ADDR_EXPR, res_type, | |
2141 | build4 (ARRAY_REF, TREE_TYPE (op0), | |
2142 | TREE_OPERAND (op0, 0), | |
2143 | gimple_assign_rhs1 (offset_def), | |
2144 | TREE_OPERAND (op0, 2), | |
2145 | TREE_OPERAND (op0, 3))); | |
2146 | else if (integer_onep (TYPE_SIZE_UNIT (TREE_TYPE (op0))) | |
2147 | && gimple_assign_rhs_code (offset_def) != MULT_EXPR) | |
2148 | return build1 (ADDR_EXPR, res_type, | |
2149 | build4 (ARRAY_REF, TREE_TYPE (op0), | |
2150 | TREE_OPERAND (op0, 0), | |
2151 | op1, | |
2152 | TREE_OPERAND (op0, 2), | |
2153 | TREE_OPERAND (op0, 3))); | |
2154 | } | |
2155 | return NULL_TREE; | |
2156 | } | |
2157 | ||
6de9cd9a DN |
2158 | /* If the first operand is an ARRAY_REF, expand it so that we can fold |
2159 | the offset into it. */ | |
2160 | while (TREE_CODE (op0) == ARRAY_REF) | |
2161 | { | |
2162 | tree array_obj = TREE_OPERAND (op0, 0); | |
2163 | tree array_idx = TREE_OPERAND (op0, 1); | |
2164 | tree elt_type = TREE_TYPE (op0); | |
2165 | tree elt_size = TYPE_SIZE_UNIT (elt_type); | |
2166 | tree min_idx; | |
2167 | ||
2168 | if (TREE_CODE (array_idx) != INTEGER_CST) | |
2169 | break; | |
2170 | if (TREE_CODE (elt_size) != INTEGER_CST) | |
2171 | break; | |
2172 | ||
2173 | /* Un-bias the index by the min index of the array type. */ | |
2174 | min_idx = TYPE_DOMAIN (TREE_TYPE (array_obj)); | |
2175 | if (min_idx) | |
2176 | { | |
2177 | min_idx = TYPE_MIN_VALUE (min_idx); | |
2178 | if (min_idx) | |
2179 | { | |
44de5aeb RK |
2180 | if (TREE_CODE (min_idx) != INTEGER_CST) |
2181 | break; | |
2182 | ||
b6f65e3c | 2183 | array_idx = fold_convert (TREE_TYPE (min_idx), array_idx); |
6de9cd9a DN |
2184 | if (!integer_zerop (min_idx)) |
2185 | array_idx = int_const_binop (MINUS_EXPR, array_idx, | |
2186 | min_idx, 0); | |
2187 | } | |
2188 | } | |
2189 | ||
2190 | /* Convert the index to a byte offset. */ | |
b6f65e3c | 2191 | array_idx = fold_convert (sizetype, array_idx); |
6de9cd9a DN |
2192 | array_idx = int_const_binop (MULT_EXPR, array_idx, elt_size, 0); |
2193 | ||
2194 | /* Update the operands for the next round, or for folding. */ | |
5be014d5 | 2195 | op1 = int_const_binop (PLUS_EXPR, |
6de9cd9a | 2196 | array_idx, op1, 0); |
6de9cd9a DN |
2197 | op0 = array_obj; |
2198 | } | |
2199 | ||
726a989a | 2200 | ptd_type = TREE_TYPE (res_type); |
c4e5b5a8 RG |
2201 | /* If we want a pointer to void, reconstruct the reference from the |
2202 | array element type. A pointer to that can be trivially converted | |
2203 | to void *. This happens as we fold (void *)(ptr p+ off). */ | |
2204 | if (VOID_TYPE_P (ptd_type) | |
2205 | && TREE_CODE (TREE_TYPE (op0)) == ARRAY_TYPE) | |
2206 | ptd_type = TREE_TYPE (TREE_TYPE (op0)); | |
6de9cd9a DN |
2207 | |
2208 | /* At which point we can try some of the same things as for indirects. */ | |
1fd89060 | 2209 | t = maybe_fold_offset_to_array_ref (op0, op1, ptd_type, true); |
6de9cd9a DN |
2210 | if (!t) |
2211 | t = maybe_fold_offset_to_component_ref (TREE_TYPE (op0), op0, op1, | |
2212 | ptd_type, false); | |
2213 | if (t) | |
726a989a | 2214 | t = build1 (ADDR_EXPR, res_type, t); |
6de9cd9a DN |
2215 | |
2216 | return t; | |
2217 | } | |
2218 | ||
622f91ba JL |
2219 | /* For passing state through walk_tree into fold_stmt_r and its |
2220 | children. */ | |
2221 | ||
2222 | struct fold_stmt_r_data | |
2223 | { | |
726a989a | 2224 | gimple stmt; |
6ac01510 ILT |
2225 | bool *changed_p; |
2226 | bool *inside_addr_expr_p; | |
622f91ba JL |
2227 | }; |
2228 | ||
6de9cd9a DN |
2229 | /* Subroutine of fold_stmt called via walk_tree. We perform several |
2230 | simplifications of EXPR_P, mostly having to do with pointer arithmetic. */ | |
2231 | ||
2232 | static tree | |
2233 | fold_stmt_r (tree *expr_p, int *walk_subtrees, void *data) | |
2234 | { | |
726a989a RB |
2235 | struct walk_stmt_info *wi = (struct walk_stmt_info *) data; |
2236 | struct fold_stmt_r_data *fold_stmt_r_data; | |
2237 | bool *inside_addr_expr_p; | |
2238 | bool *changed_p; | |
6de9cd9a | 2239 | tree expr = *expr_p, t; |
6aaa4013 | 2240 | bool volatile_p = TREE_THIS_VOLATILE (expr); |
6de9cd9a | 2241 | |
726a989a RB |
2242 | fold_stmt_r_data = (struct fold_stmt_r_data *) wi->info; |
2243 | inside_addr_expr_p = fold_stmt_r_data->inside_addr_expr_p; | |
2244 | changed_p = fold_stmt_r_data->changed_p; | |
2245 | ||
6de9cd9a DN |
2246 | /* ??? It'd be nice if walk_tree had a pre-order option. */ |
2247 | switch (TREE_CODE (expr)) | |
2248 | { | |
2249 | case INDIRECT_REF: | |
2250 | t = walk_tree (&TREE_OPERAND (expr, 0), fold_stmt_r, data, NULL); | |
2251 | if (t) | |
2252 | return t; | |
2253 | *walk_subtrees = 0; | |
2254 | ||
2255 | t = maybe_fold_stmt_indirect (expr, TREE_OPERAND (expr, 0), | |
2256 | integer_zero_node); | |
bab4e8fb JJ |
2257 | /* Avoid folding *"abc" = 5 into 'a' = 5. */ |
2258 | if (wi->is_lhs && t && TREE_CODE (t) == INTEGER_CST) | |
2259 | t = NULL_TREE; | |
16ac8575 RG |
2260 | if (!t |
2261 | && TREE_CODE (TREE_OPERAND (expr, 0)) == ADDR_EXPR) | |
2262 | /* If we had a good reason for propagating the address here, | |
2263 | make sure we end up with valid gimple. See PR34989. */ | |
2264 | t = TREE_OPERAND (TREE_OPERAND (expr, 0), 0); | |
6de9cd9a DN |
2265 | break; |
2266 | ||
fe9821b8 JH |
2267 | case NOP_EXPR: |
2268 | t = walk_tree (&TREE_OPERAND (expr, 0), fold_stmt_r, data, NULL); | |
2269 | if (t) | |
2270 | return t; | |
2271 | *walk_subtrees = 0; | |
2272 | ||
2273 | if (POINTER_TYPE_P (TREE_TYPE (expr)) | |
129a37fc | 2274 | && POINTER_TYPE_P (TREE_TYPE (TREE_TYPE (expr))) |
fe9821b8 | 2275 | && POINTER_TYPE_P (TREE_TYPE (TREE_OPERAND (expr, 0))) |
99f536cc RG |
2276 | && (t = maybe_fold_offset_to_address (TREE_OPERAND (expr, 0), |
2277 | integer_zero_node, | |
2278 | TREE_TYPE (TREE_TYPE (expr))))) | |
2279 | return t; | |
fe9821b8 JH |
2280 | break; |
2281 | ||
622f91ba | 2282 | /* ??? Could handle more ARRAY_REFs here, as a variant of INDIRECT_REF. |
6de9cd9a DN |
2283 | We'd only want to bother decomposing an existing ARRAY_REF if |
2284 | the base array is found to have another offset contained within. | |
2285 | Otherwise we'd be wasting time. */ | |
622f91ba JL |
2286 | case ARRAY_REF: |
2287 | /* If we are not processing expressions found within an | |
bab4e8fb JJ |
2288 | ADDR_EXPR, then we can fold constant array references. |
2289 | Don't fold on LHS either, to avoid folding "abc"[0] = 5 | |
2290 | into 'a' = 5. */ | |
2291 | if (!*inside_addr_expr_p && !wi->is_lhs) | |
622f91ba JL |
2292 | t = fold_read_from_constant_string (expr); |
2293 | else | |
2294 | t = NULL; | |
2295 | break; | |
6de9cd9a DN |
2296 | |
2297 | case ADDR_EXPR: | |
622f91ba | 2298 | *inside_addr_expr_p = true; |
6de9cd9a | 2299 | t = walk_tree (&TREE_OPERAND (expr, 0), fold_stmt_r, data, NULL); |
622f91ba | 2300 | *inside_addr_expr_p = false; |
6de9cd9a DN |
2301 | if (t) |
2302 | return t; | |
2303 | *walk_subtrees = 0; | |
2304 | ||
51eed280 PB |
2305 | /* Make sure the value is properly considered constant, and so gets |
2306 | propagated as expected. */ | |
6de9cd9a | 2307 | if (*changed_p) |
127203ac | 2308 | recompute_tree_invariant_for_addr_expr (expr); |
6de9cd9a DN |
2309 | return NULL_TREE; |
2310 | ||
6de9cd9a DN |
2311 | case COMPONENT_REF: |
2312 | t = walk_tree (&TREE_OPERAND (expr, 0), fold_stmt_r, data, NULL); | |
2313 | if (t) | |
2314 | return t; | |
2315 | *walk_subtrees = 0; | |
2316 | ||
fa27426e RH |
2317 | /* Make sure the FIELD_DECL is actually a field in the type on the lhs. |
2318 | We've already checked that the records are compatible, so we should | |
2319 | come up with a set of compatible fields. */ | |
2320 | { | |
2321 | tree expr_record = TREE_TYPE (TREE_OPERAND (expr, 0)); | |
2322 | tree expr_field = TREE_OPERAND (expr, 1); | |
2323 | ||
2324 | if (DECL_FIELD_CONTEXT (expr_field) != TYPE_MAIN_VARIANT (expr_record)) | |
2325 | { | |
2326 | expr_field = find_compatible_field (expr_record, expr_field); | |
2327 | TREE_OPERAND (expr, 1) = expr_field; | |
2328 | } | |
2329 | } | |
6de9cd9a DN |
2330 | break; |
2331 | ||
ac182688 ZD |
2332 | case TARGET_MEM_REF: |
2333 | t = maybe_fold_tmr (expr); | |
2334 | break; | |
2335 | ||
726a989a RB |
2336 | case POINTER_PLUS_EXPR: |
2337 | t = walk_tree (&TREE_OPERAND (expr, 0), fold_stmt_r, data, NULL); | |
2338 | if (t) | |
2339 | return t; | |
2340 | t = walk_tree (&TREE_OPERAND (expr, 1), fold_stmt_r, data, NULL); | |
2341 | if (t) | |
2342 | return t; | |
2343 | *walk_subtrees = 0; | |
2344 | ||
2345 | t = maybe_fold_stmt_addition (TREE_TYPE (expr), | |
2346 | TREE_OPERAND (expr, 0), | |
2347 | TREE_OPERAND (expr, 1)); | |
2348 | break; | |
2349 | ||
f393e7f5 RG |
2350 | case COND_EXPR: |
2351 | if (COMPARISON_CLASS_P (TREE_OPERAND (expr, 0))) | |
2352 | { | |
2353 | tree op0 = TREE_OPERAND (expr, 0); | |
6ac01510 ILT |
2354 | tree tem; |
2355 | bool set; | |
2356 | ||
2357 | fold_defer_overflow_warnings (); | |
2358 | tem = fold_binary (TREE_CODE (op0), TREE_TYPE (op0), | |
2359 | TREE_OPERAND (op0, 0), | |
2360 | TREE_OPERAND (op0, 1)); | |
726a989a RB |
2361 | /* This is actually a conditional expression, not a GIMPLE |
2362 | conditional statement, however, the valid_gimple_rhs_p | |
2363 | test still applies. */ | |
2364 | set = tem && is_gimple_condexpr (tem) && valid_gimple_rhs_p (tem); | |
6ac01510 ILT |
2365 | fold_undefer_overflow_warnings (set, fold_stmt_r_data->stmt, 0); |
2366 | if (set) | |
5cdc4a26 | 2367 | { |
726a989a RB |
2368 | COND_EXPR_COND (expr) = tem; |
2369 | t = expr; | |
5cdc4a26 RS |
2370 | break; |
2371 | } | |
f393e7f5 | 2372 | } |
5cdc4a26 | 2373 | return NULL_TREE; |
f393e7f5 | 2374 | |
6de9cd9a DN |
2375 | default: |
2376 | return NULL_TREE; | |
2377 | } | |
2378 | ||
2379 | if (t) | |
2380 | { | |
e2104f59 RG |
2381 | /* Preserve volatileness of the original expression. |
2382 | We can end up with a plain decl here which is shared | |
2383 | and we shouldn't mess with its flags. */ | |
2384 | if (!SSA_VAR_P (t)) | |
2385 | TREE_THIS_VOLATILE (t) = volatile_p; | |
6de9cd9a DN |
2386 | *expr_p = t; |
2387 | *changed_p = true; | |
2388 | } | |
2389 | ||
2390 | return NULL_TREE; | |
2391 | } | |
2392 | ||
10a0d495 JJ |
2393 | /* Return the string length, maximum string length or maximum value of |
2394 | ARG in LENGTH. | |
2395 | If ARG is an SSA name variable, follow its use-def chains. If LENGTH | |
2396 | is not NULL and, for TYPE == 0, its value is not equal to the length | |
2397 | we determine or if we are unable to determine the length or value, | |
2398 | return false. VISITED is a bitmap of visited variables. | |
2399 | TYPE is 0 if string length should be returned, 1 for maximum string | |
2400 | length and 2 for maximum value ARG can have. */ | |
6de9cd9a | 2401 | |
06a9b53f | 2402 | static bool |
10a0d495 | 2403 | get_maxval_strlen (tree arg, tree *length, bitmap visited, int type) |
6de9cd9a | 2404 | { |
726a989a RB |
2405 | tree var, val; |
2406 | gimple def_stmt; | |
750628d8 DN |
2407 | |
2408 | if (TREE_CODE (arg) != SSA_NAME) | |
06a9b53f | 2409 | { |
f255541f RC |
2410 | if (TREE_CODE (arg) == COND_EXPR) |
2411 | return get_maxval_strlen (COND_EXPR_THEN (arg), length, visited, type) | |
2412 | && get_maxval_strlen (COND_EXPR_ELSE (arg), length, visited, type); | |
c4e5b5a8 RG |
2413 | /* We can end up with &(*iftmp_1)[0] here as well, so handle it. */ |
2414 | else if (TREE_CODE (arg) == ADDR_EXPR | |
2415 | && TREE_CODE (TREE_OPERAND (arg, 0)) == ARRAY_REF | |
2416 | && integer_zerop (TREE_OPERAND (TREE_OPERAND (arg, 0), 1))) | |
2417 | { | |
2418 | tree aop0 = TREE_OPERAND (TREE_OPERAND (arg, 0), 0); | |
2419 | if (TREE_CODE (aop0) == INDIRECT_REF | |
2420 | && TREE_CODE (TREE_OPERAND (aop0, 0)) == SSA_NAME) | |
2421 | return get_maxval_strlen (TREE_OPERAND (aop0, 0), | |
2422 | length, visited, type); | |
2423 | } | |
f255541f | 2424 | |
10a0d495 JJ |
2425 | if (type == 2) |
2426 | { | |
2427 | val = arg; | |
2428 | if (TREE_CODE (val) != INTEGER_CST | |
2429 | || tree_int_cst_sgn (val) < 0) | |
2430 | return false; | |
2431 | } | |
2432 | else | |
2433 | val = c_strlen (arg, 1); | |
750628d8 | 2434 | if (!val) |
06a9b53f | 2435 | return false; |
cd709752 | 2436 | |
10a0d495 JJ |
2437 | if (*length) |
2438 | { | |
2439 | if (type > 0) | |
2440 | { | |
2441 | if (TREE_CODE (*length) != INTEGER_CST | |
2442 | || TREE_CODE (val) != INTEGER_CST) | |
2443 | return false; | |
2444 | ||
2445 | if (tree_int_cst_lt (*length, val)) | |
2446 | *length = val; | |
2447 | return true; | |
2448 | } | |
2449 | else if (simple_cst_equal (val, *length) != 1) | |
2450 | return false; | |
2451 | } | |
6de9cd9a | 2452 | |
750628d8 DN |
2453 | *length = val; |
2454 | return true; | |
6de9cd9a | 2455 | } |
06a9b53f | 2456 | |
750628d8 DN |
2457 | /* If we were already here, break the infinite cycle. */ |
2458 | if (bitmap_bit_p (visited, SSA_NAME_VERSION (arg))) | |
2459 | return true; | |
2460 | bitmap_set_bit (visited, SSA_NAME_VERSION (arg)); | |
2461 | ||
2462 | var = arg; | |
2463 | def_stmt = SSA_NAME_DEF_STMT (var); | |
6de9cd9a | 2464 | |
726a989a RB |
2465 | switch (gimple_code (def_stmt)) |
2466 | { | |
2467 | case GIMPLE_ASSIGN: | |
2468 | /* The RHS of the statement defining VAR must either have a | |
2469 | constant length or come from another SSA_NAME with a constant | |
2470 | length. */ | |
2471 | if (gimple_assign_single_p (def_stmt) | |
2472 | || gimple_assign_unary_nop_p (def_stmt)) | |
2473 | { | |
2474 | tree rhs = gimple_assign_rhs1 (def_stmt); | |
2475 | return get_maxval_strlen (rhs, length, visited, type); | |
2476 | } | |
2477 | return false; | |
2478 | ||
2479 | case GIMPLE_PHI: | |
750628d8 DN |
2480 | { |
2481 | /* All the arguments of the PHI node must have the same constant | |
2482 | length. */ | |
726a989a RB |
2483 | unsigned i; |
2484 | ||
2485 | for (i = 0; i < gimple_phi_num_args (def_stmt); i++) | |
2486 | { | |
2487 | tree arg = gimple_phi_arg (def_stmt, i)->def; | |
2488 | ||
2489 | /* If this PHI has itself as an argument, we cannot | |
2490 | determine the string length of this argument. However, | |
2491 | if we can find a constant string length for the other | |
2492 | PHI args then we can still be sure that this is a | |
2493 | constant string length. So be optimistic and just | |
2494 | continue with the next argument. */ | |
2495 | if (arg == gimple_phi_result (def_stmt)) | |
2496 | continue; | |
2497 | ||
2498 | if (!get_maxval_strlen (arg, length, visited, type)) | |
2499 | return false; | |
2500 | } | |
2501 | } | |
2502 | return true; | |
6de9cd9a | 2503 | |
750628d8 | 2504 | default: |
726a989a | 2505 | return false; |
6de9cd9a | 2506 | } |
6de9cd9a DN |
2507 | } |
2508 | ||
2509 | ||
726a989a RB |
2510 | /* Fold builtin call in statement STMT. Returns a simplified tree. |
2511 | We may return a non-constant expression, including another call | |
2512 | to a different function and with different arguments, e.g., | |
2513 | substituting memcpy for strcpy when the string length is known. | |
2514 | Note that some builtins expand into inline code that may not | |
2515 | be valid in GIMPLE. Callers must take care. */ | |
6de9cd9a DN |
2516 | |
2517 | static tree | |
726a989a | 2518 | ccp_fold_builtin (gimple stmt) |
6de9cd9a | 2519 | { |
10a0d495 | 2520 | tree result, val[3]; |
5039610b | 2521 | tree callee, a; |
d9cc481a | 2522 | int arg_idx, type; |
a32e70c3 RS |
2523 | bitmap visited; |
2524 | bool ignore; | |
5039610b | 2525 | int nargs; |
6de9cd9a | 2526 | |
726a989a RB |
2527 | gcc_assert (is_gimple_call (stmt)); |
2528 | ||
2529 | ignore = (gimple_call_lhs (stmt) == NULL); | |
6de9cd9a DN |
2530 | |
2531 | /* First try the generic builtin folder. If that succeeds, return the | |
2532 | result directly. */ | |
726a989a | 2533 | result = fold_call_stmt (stmt, ignore); |
6de9cd9a | 2534 | if (result) |
10a0d495 JJ |
2535 | { |
2536 | if (ignore) | |
2537 | STRIP_NOPS (result); | |
2538 | return result; | |
2539 | } | |
a32e70c3 RS |
2540 | |
2541 | /* Ignore MD builtins. */ | |
726a989a | 2542 | callee = gimple_call_fndecl (stmt); |
a32e70c3 RS |
2543 | if (DECL_BUILT_IN_CLASS (callee) == BUILT_IN_MD) |
2544 | return NULL_TREE; | |
6de9cd9a DN |
2545 | |
2546 | /* If the builtin could not be folded, and it has no argument list, | |
2547 | we're done. */ | |
726a989a | 2548 | nargs = gimple_call_num_args (stmt); |
5039610b | 2549 | if (nargs == 0) |
6de9cd9a DN |
2550 | return NULL_TREE; |
2551 | ||
2552 | /* Limit the work only for builtins we know how to simplify. */ | |
2553 | switch (DECL_FUNCTION_CODE (callee)) | |
2554 | { | |
2555 | case BUILT_IN_STRLEN: | |
2556 | case BUILT_IN_FPUTS: | |
2557 | case BUILT_IN_FPUTS_UNLOCKED: | |
d9cc481a | 2558 | arg_idx = 0; |
10a0d495 | 2559 | type = 0; |
6de9cd9a DN |
2560 | break; |
2561 | case BUILT_IN_STRCPY: | |
2562 | case BUILT_IN_STRNCPY: | |
d9cc481a | 2563 | arg_idx = 1; |
10a0d495 JJ |
2564 | type = 0; |
2565 | break; | |
2566 | case BUILT_IN_MEMCPY_CHK: | |
2567 | case BUILT_IN_MEMPCPY_CHK: | |
2568 | case BUILT_IN_MEMMOVE_CHK: | |
2569 | case BUILT_IN_MEMSET_CHK: | |
2570 | case BUILT_IN_STRNCPY_CHK: | |
d9cc481a | 2571 | arg_idx = 2; |
10a0d495 JJ |
2572 | type = 2; |
2573 | break; | |
2574 | case BUILT_IN_STRCPY_CHK: | |
2575 | case BUILT_IN_STPCPY_CHK: | |
d9cc481a | 2576 | arg_idx = 1; |
10a0d495 JJ |
2577 | type = 1; |
2578 | break; | |
2579 | case BUILT_IN_SNPRINTF_CHK: | |
2580 | case BUILT_IN_VSNPRINTF_CHK: | |
d9cc481a | 2581 | arg_idx = 1; |
10a0d495 | 2582 | type = 2; |
6de9cd9a DN |
2583 | break; |
2584 | default: | |
2585 | return NULL_TREE; | |
2586 | } | |
2587 | ||
f6ab27bb JJ |
2588 | if (arg_idx >= nargs) |
2589 | return NULL_TREE; | |
2590 | ||
6de9cd9a | 2591 | /* Try to use the dataflow information gathered by the CCP process. */ |
8bdbfff5 | 2592 | visited = BITMAP_ALLOC (NULL); |
d9cc481a | 2593 | bitmap_clear (visited); |
6de9cd9a | 2594 | |
10a0d495 | 2595 | memset (val, 0, sizeof (val)); |
d9cc481a AN |
2596 | a = gimple_call_arg (stmt, arg_idx); |
2597 | if (!get_maxval_strlen (a, &val[arg_idx], visited, type)) | |
2598 | val[arg_idx] = NULL_TREE; | |
6de9cd9a | 2599 | |
8bdbfff5 | 2600 | BITMAP_FREE (visited); |
6de9cd9a | 2601 | |
a32e70c3 | 2602 | result = NULL_TREE; |
6de9cd9a DN |
2603 | switch (DECL_FUNCTION_CODE (callee)) |
2604 | { | |
2605 | case BUILT_IN_STRLEN: | |
f6ab27bb | 2606 | if (val[0] && nargs == 1) |
6de9cd9a | 2607 | { |
726a989a RB |
2608 | tree new_val = |
2609 | fold_convert (TREE_TYPE (gimple_call_lhs (stmt)), val[0]); | |
6de9cd9a DN |
2610 | |
2611 | /* If the result is not a valid gimple value, or not a cast | |
2612 | of a valid gimple value, then we can not use the result. */ | |
c22940cd TN |
2613 | if (is_gimple_val (new_val) |
2614 | || (is_gimple_cast (new_val) | |
2615 | && is_gimple_val (TREE_OPERAND (new_val, 0)))) | |
2616 | return new_val; | |
6de9cd9a | 2617 | } |
a32e70c3 RS |
2618 | break; |
2619 | ||
6de9cd9a | 2620 | case BUILT_IN_STRCPY: |
5039610b SL |
2621 | if (val[1] && is_gimple_val (val[1]) && nargs == 2) |
2622 | result = fold_builtin_strcpy (callee, | |
726a989a RB |
2623 | gimple_call_arg (stmt, 0), |
2624 | gimple_call_arg (stmt, 1), | |
5039610b | 2625 | val[1]); |
a32e70c3 RS |
2626 | break; |
2627 | ||
6de9cd9a | 2628 | case BUILT_IN_STRNCPY: |
5039610b SL |
2629 | if (val[1] && is_gimple_val (val[1]) && nargs == 3) |
2630 | result = fold_builtin_strncpy (callee, | |
726a989a RB |
2631 | gimple_call_arg (stmt, 0), |
2632 | gimple_call_arg (stmt, 1), | |
2633 | gimple_call_arg (stmt, 2), | |
5039610b | 2634 | val[1]); |
a32e70c3 RS |
2635 | break; |
2636 | ||
6de9cd9a | 2637 | case BUILT_IN_FPUTS: |
f6ab27bb JJ |
2638 | if (nargs == 2) |
2639 | result = fold_builtin_fputs (gimple_call_arg (stmt, 0), | |
2640 | gimple_call_arg (stmt, 1), | |
2641 | ignore, false, val[0]); | |
a32e70c3 RS |
2642 | break; |
2643 | ||
6de9cd9a | 2644 | case BUILT_IN_FPUTS_UNLOCKED: |
f6ab27bb JJ |
2645 | if (nargs == 2) |
2646 | result = fold_builtin_fputs (gimple_call_arg (stmt, 0), | |
2647 | gimple_call_arg (stmt, 1), | |
2648 | ignore, true, val[0]); | |
10a0d495 JJ |
2649 | break; |
2650 | ||
2651 | case BUILT_IN_MEMCPY_CHK: | |
2652 | case BUILT_IN_MEMPCPY_CHK: | |
2653 | case BUILT_IN_MEMMOVE_CHK: | |
2654 | case BUILT_IN_MEMSET_CHK: | |
f6ab27bb | 2655 | if (val[2] && is_gimple_val (val[2]) && nargs == 4) |
5039610b | 2656 | result = fold_builtin_memory_chk (callee, |
726a989a RB |
2657 | gimple_call_arg (stmt, 0), |
2658 | gimple_call_arg (stmt, 1), | |
2659 | gimple_call_arg (stmt, 2), | |
2660 | gimple_call_arg (stmt, 3), | |
5039610b | 2661 | val[2], ignore, |
10a0d495 JJ |
2662 | DECL_FUNCTION_CODE (callee)); |
2663 | break; | |
2664 | ||
2665 | case BUILT_IN_STRCPY_CHK: | |
2666 | case BUILT_IN_STPCPY_CHK: | |
f6ab27bb | 2667 | if (val[1] && is_gimple_val (val[1]) && nargs == 3) |
5039610b | 2668 | result = fold_builtin_stxcpy_chk (callee, |
726a989a RB |
2669 | gimple_call_arg (stmt, 0), |
2670 | gimple_call_arg (stmt, 1), | |
2671 | gimple_call_arg (stmt, 2), | |
5039610b | 2672 | val[1], ignore, |
10a0d495 JJ |
2673 | DECL_FUNCTION_CODE (callee)); |
2674 | break; | |
2675 | ||
2676 | case BUILT_IN_STRNCPY_CHK: | |
f6ab27bb | 2677 | if (val[2] && is_gimple_val (val[2]) && nargs == 4) |
726a989a RB |
2678 | result = fold_builtin_strncpy_chk (gimple_call_arg (stmt, 0), |
2679 | gimple_call_arg (stmt, 1), | |
2680 | gimple_call_arg (stmt, 2), | |
2681 | gimple_call_arg (stmt, 3), | |
5039610b | 2682 | val[2]); |
10a0d495 JJ |
2683 | break; |
2684 | ||
2685 | case BUILT_IN_SNPRINTF_CHK: | |
2686 | case BUILT_IN_VSNPRINTF_CHK: | |
2687 | if (val[1] && is_gimple_val (val[1])) | |
726a989a RB |
2688 | result = gimple_fold_builtin_snprintf_chk (stmt, val[1], |
2689 | DECL_FUNCTION_CODE (callee)); | |
a32e70c3 | 2690 | break; |
6de9cd9a DN |
2691 | |
2692 | default: | |
1e128c5f | 2693 | gcc_unreachable (); |
6de9cd9a DN |
2694 | } |
2695 | ||
a32e70c3 | 2696 | if (result && ignore) |
9675412f | 2697 | result = fold_ignored_result (result); |
a32e70c3 | 2698 | return result; |
6de9cd9a DN |
2699 | } |
2700 | ||
726a989a RB |
2701 | /* Attempt to fold an assignment statement pointed-to by SI. Returns a |
2702 | replacement rhs for the statement or NULL_TREE if no simplification | |
2703 | could be made. It is assumed that the operands have been previously | |
2704 | folded. */ | |
2705 | ||
2706 | static tree | |
2707 | fold_gimple_assign (gimple_stmt_iterator *si) | |
2708 | { | |
2709 | gimple stmt = gsi_stmt (*si); | |
2710 | enum tree_code subcode = gimple_assign_rhs_code (stmt); | |
2711 | ||
2712 | tree result = NULL; | |
2713 | ||
2714 | switch (get_gimple_rhs_class (subcode)) | |
2715 | { | |
2716 | case GIMPLE_SINGLE_RHS: | |
2717 | { | |
2718 | tree rhs = gimple_assign_rhs1 (stmt); | |
2719 | ||
2720 | /* Try to fold a conditional expression. */ | |
2721 | if (TREE_CODE (rhs) == COND_EXPR) | |
2722 | { | |
2723 | tree temp = fold (COND_EXPR_COND (rhs)); | |
2724 | if (temp != COND_EXPR_COND (rhs)) | |
2725 | result = fold_build3 (COND_EXPR, TREE_TYPE (rhs), temp, | |
2726 | COND_EXPR_THEN (rhs), COND_EXPR_ELSE (rhs)); | |
2727 | } | |
2728 | ||
2729 | /* If we couldn't fold the RHS, hand over to the generic | |
2730 | fold routines. */ | |
2731 | if (result == NULL_TREE) | |
2732 | result = fold (rhs); | |
2733 | ||
2734 | /* Strip away useless type conversions. Both the NON_LVALUE_EXPR | |
2735 | that may have been added by fold, and "useless" type | |
2736 | conversions that might now be apparent due to propagation. */ | |
2737 | STRIP_USELESS_TYPE_CONVERSION (result); | |
2738 | ||
2739 | if (result != rhs && valid_gimple_rhs_p (result)) | |
2740 | return result; | |
2741 | else | |
2742 | /* It is possible that fold_stmt_r simplified the RHS. | |
2743 | Make sure that the subcode of this statement still | |
2744 | reflects the principal operator of the rhs operand. */ | |
2745 | return rhs; | |
2746 | } | |
2747 | break; | |
2748 | ||
2749 | case GIMPLE_UNARY_RHS: | |
ff8b183b RG |
2750 | { |
2751 | tree rhs = gimple_assign_rhs1 (stmt); | |
726a989a | 2752 | |
ff8b183b RG |
2753 | result = fold_unary (subcode, gimple_expr_type (stmt), rhs); |
2754 | if (result) | |
2755 | { | |
2756 | /* If the operation was a conversion do _not_ mark a | |
2757 | resulting constant with TREE_OVERFLOW if the original | |
2758 | constant was not. These conversions have implementation | |
2759 | defined behavior and retaining the TREE_OVERFLOW flag | |
2760 | here would confuse later passes such as VRP. */ | |
2761 | if (CONVERT_EXPR_CODE_P (subcode) | |
2762 | && TREE_CODE (result) == INTEGER_CST | |
2763 | && TREE_CODE (rhs) == INTEGER_CST) | |
2764 | TREE_OVERFLOW (result) = TREE_OVERFLOW (rhs); | |
2765 | ||
2766 | STRIP_USELESS_TYPE_CONVERSION (result); | |
2767 | if (valid_gimple_rhs_p (result)) | |
2768 | return result; | |
2769 | } | |
2770 | else if (CONVERT_EXPR_CODE_P (subcode) | |
2771 | && POINTER_TYPE_P (gimple_expr_type (stmt)) | |
2772 | && POINTER_TYPE_P (TREE_TYPE (gimple_assign_rhs1 (stmt)))) | |
2773 | { | |
2774 | tree type = gimple_expr_type (stmt); | |
2775 | tree t = maybe_fold_offset_to_address (gimple_assign_rhs1 (stmt), | |
2776 | integer_zero_node, type); | |
2777 | if (t) | |
2778 | return t; | |
2779 | } | |
2780 | } | |
726a989a RB |
2781 | break; |
2782 | ||
2783 | case GIMPLE_BINARY_RHS: | |
2784 | /* Try to fold pointer addition. */ | |
2785 | if (gimple_assign_rhs_code (stmt) == POINTER_PLUS_EXPR) | |
66e8b99c RG |
2786 | { |
2787 | tree type = TREE_TYPE (gimple_assign_rhs1 (stmt)); | |
2788 | if (TREE_CODE (TREE_TYPE (type)) == ARRAY_TYPE) | |
2789 | { | |
2790 | type = build_pointer_type (TREE_TYPE (TREE_TYPE (type))); | |
2791 | if (!useless_type_conversion_p | |
2792 | (TREE_TYPE (gimple_assign_lhs (stmt)), type)) | |
2793 | type = TREE_TYPE (gimple_assign_rhs1 (stmt)); | |
2794 | } | |
2795 | result = maybe_fold_stmt_addition (type, | |
2796 | gimple_assign_rhs1 (stmt), | |
2797 | gimple_assign_rhs2 (stmt)); | |
2798 | } | |
726a989a RB |
2799 | |
2800 | if (!result) | |
2801 | result = fold_binary (subcode, | |
2802 | TREE_TYPE (gimple_assign_lhs (stmt)), | |
2803 | gimple_assign_rhs1 (stmt), | |
2804 | gimple_assign_rhs2 (stmt)); | |
2805 | ||
2806 | if (result) | |
2807 | { | |
2808 | STRIP_USELESS_TYPE_CONVERSION (result); | |
2809 | if (valid_gimple_rhs_p (result)) | |
2810 | return result; | |
001003c2 PB |
2811 | |
2812 | /* Fold might have produced non-GIMPLE, so if we trust it blindly | |
2813 | we lose canonicalization opportunities. Do not go again | |
2814 | through fold here though, or the same non-GIMPLE will be | |
2815 | produced. */ | |
2816 | if (commutative_tree_code (subcode) | |
2817 | && tree_swap_operands_p (gimple_assign_rhs1 (stmt), | |
2818 | gimple_assign_rhs2 (stmt), false)) | |
2819 | return build2 (subcode, TREE_TYPE (gimple_assign_lhs (stmt)), | |
2820 | gimple_assign_rhs2 (stmt), | |
2821 | gimple_assign_rhs1 (stmt)); | |
726a989a RB |
2822 | } |
2823 | break; | |
2824 | ||
2825 | case GIMPLE_INVALID_RHS: | |
2826 | gcc_unreachable (); | |
2827 | } | |
2828 | ||
2829 | return NULL_TREE; | |
2830 | } | |
2831 | ||
2832 | /* Attempt to fold a conditional statement. Return true if any changes were | |
2833 | made. We only attempt to fold the condition expression, and do not perform | |
2834 | any transformation that would require alteration of the cfg. It is | |
2835 | assumed that the operands have been previously folded. */ | |
2836 | ||
2837 | static bool | |
2838 | fold_gimple_cond (gimple stmt) | |
2839 | { | |
2840 | tree result = fold_binary (gimple_cond_code (stmt), | |
2841 | boolean_type_node, | |
2842 | gimple_cond_lhs (stmt), | |
2843 | gimple_cond_rhs (stmt)); | |
2844 | ||
2845 | if (result) | |
2846 | { | |
2847 | STRIP_USELESS_TYPE_CONVERSION (result); | |
2848 | if (is_gimple_condexpr (result) && valid_gimple_rhs_p (result)) | |
2849 | { | |
2850 | gimple_cond_set_condition_from_tree (stmt, result); | |
2851 | return true; | |
2852 | } | |
2853 | } | |
2854 | ||
2855 | return false; | |
2856 | } | |
2857 | ||
2858 | ||
2859 | /* Attempt to fold a call statement referenced by the statement iterator GSI. | |
2860 | The statement may be replaced by another statement, e.g., if the call | |
2861 | simplifies to a constant value. Return true if any changes were made. | |
2862 | It is assumed that the operands have been previously folded. */ | |
2863 | ||
2864 | static bool | |
2865 | fold_gimple_call (gimple_stmt_iterator *gsi) | |
2866 | { | |
2867 | gimple stmt = gsi_stmt (*gsi); | |
2868 | ||
2869 | tree callee = gimple_call_fndecl (stmt); | |
2870 | ||
2871 | /* Check for builtins that CCP can handle using information not | |
2872 | available in the generic fold routines. */ | |
2873 | if (callee && DECL_BUILT_IN (callee)) | |
2874 | { | |
2875 | tree result = ccp_fold_builtin (stmt); | |
2876 | ||
2877 | if (result) | |
2878 | return update_call_from_tree (gsi, result); | |
2879 | } | |
2880 | else | |
2881 | { | |
2882 | /* Check for resolvable OBJ_TYPE_REF. The only sorts we can resolve | |
2883 | here are when we've propagated the address of a decl into the | |
2884 | object slot. */ | |
2885 | /* ??? Should perhaps do this in fold proper. However, doing it | |
2886 | there requires that we create a new CALL_EXPR, and that requires | |
2887 | copying EH region info to the new node. Easier to just do it | |
2888 | here where we can just smash the call operand. */ | |
2889 | /* ??? Is there a good reason not to do this in fold_stmt_inplace? */ | |
2890 | callee = gimple_call_fn (stmt); | |
2891 | if (TREE_CODE (callee) == OBJ_TYPE_REF | |
2892 | && lang_hooks.fold_obj_type_ref | |
2893 | && TREE_CODE (OBJ_TYPE_REF_OBJECT (callee)) == ADDR_EXPR | |
2894 | && DECL_P (TREE_OPERAND | |
2895 | (OBJ_TYPE_REF_OBJECT (callee), 0))) | |
2896 | { | |
2897 | tree t; | |
2898 | ||
2899 | /* ??? Caution: Broken ADDR_EXPR semantics means that | |
2900 | looking at the type of the operand of the addr_expr | |
2901 | can yield an array type. See silly exception in | |
2902 | check_pointer_types_r. */ | |
2903 | t = TREE_TYPE (TREE_TYPE (OBJ_TYPE_REF_OBJECT (callee))); | |
2904 | t = lang_hooks.fold_obj_type_ref (callee, t); | |
2905 | if (t) | |
2906 | { | |
2907 | gimple_call_set_fn (stmt, t); | |
2908 | return true; | |
2909 | } | |
2910 | } | |
2911 | } | |
2912 | ||
2913 | return false; | |
2914 | } | |
6de9cd9a | 2915 | |
726a989a | 2916 | /* Fold the statement pointed to by GSI. In some cases, this function may |
750628d8 DN |
2917 | replace the whole statement with a new one. Returns true iff folding |
2918 | makes any changes. */ | |
6de9cd9a | 2919 | |
750628d8 | 2920 | bool |
726a989a | 2921 | fold_stmt (gimple_stmt_iterator *gsi) |
6de9cd9a | 2922 | { |
726a989a | 2923 | tree res; |
622f91ba | 2924 | struct fold_stmt_r_data fold_stmt_r_data; |
726a989a RB |
2925 | struct walk_stmt_info wi; |
2926 | ||
750628d8 | 2927 | bool changed = false; |
622f91ba JL |
2928 | bool inside_addr_expr = false; |
2929 | ||
726a989a | 2930 | gimple stmt = gsi_stmt (*gsi); |
6ac01510 ILT |
2931 | |
2932 | fold_stmt_r_data.stmt = stmt; | |
622f91ba JL |
2933 | fold_stmt_r_data.changed_p = &changed; |
2934 | fold_stmt_r_data.inside_addr_expr_p = &inside_addr_expr; | |
6de9cd9a | 2935 | |
726a989a RB |
2936 | memset (&wi, 0, sizeof (wi)); |
2937 | wi.info = &fold_stmt_r_data; | |
6de9cd9a | 2938 | |
726a989a RB |
2939 | /* Fold the individual operands. |
2940 | For example, fold instances of *&VAR into VAR, etc. */ | |
2941 | res = walk_gimple_op (stmt, fold_stmt_r, &wi); | |
2942 | gcc_assert (!res); | |
6de9cd9a | 2943 | |
726a989a RB |
2944 | /* Fold the main computation performed by the statement. */ |
2945 | switch (gimple_code (stmt)) | |
6de9cd9a | 2946 | { |
726a989a RB |
2947 | case GIMPLE_ASSIGN: |
2948 | { | |
2949 | tree new_rhs = fold_gimple_assign (gsi); | |
2950 | if (new_rhs != NULL_TREE) | |
2951 | { | |
2952 | gimple_assign_set_rhs_from_tree (gsi, new_rhs); | |
2953 | changed = true; | |
2954 | } | |
2955 | stmt = gsi_stmt (*gsi); | |
2956 | break; | |
2957 | } | |
2958 | case GIMPLE_COND: | |
2959 | changed |= fold_gimple_cond (stmt); | |
2960 | break; | |
2961 | case GIMPLE_CALL: | |
2962 | /* The entire statement may be replaced in this case. */ | |
2963 | changed |= fold_gimple_call (gsi); | |
2964 | break; | |
1809ff6b | 2965 | |
726a989a RB |
2966 | default: |
2967 | return changed; | |
2968 | break; | |
f255541f | 2969 | } |
6de9cd9a | 2970 | |
750628d8 | 2971 | return changed; |
6de9cd9a DN |
2972 | } |
2973 | ||
38965eb2 ZD |
2974 | /* Perform the minimal folding on statement STMT. Only operations like |
2975 | *&x created by constant propagation are handled. The statement cannot | |
726a989a RB |
2976 | be replaced with a new one. Return true if the statement was |
2977 | changed, false otherwise. */ | |
38965eb2 ZD |
2978 | |
2979 | bool | |
726a989a | 2980 | fold_stmt_inplace (gimple stmt) |
38965eb2 | 2981 | { |
726a989a | 2982 | tree res; |
622f91ba | 2983 | struct fold_stmt_r_data fold_stmt_r_data; |
726a989a RB |
2984 | struct walk_stmt_info wi; |
2985 | gimple_stmt_iterator si; | |
2986 | ||
38965eb2 | 2987 | bool changed = false; |
622f91ba JL |
2988 | bool inside_addr_expr = false; |
2989 | ||
6ac01510 | 2990 | fold_stmt_r_data.stmt = stmt; |
622f91ba JL |
2991 | fold_stmt_r_data.changed_p = &changed; |
2992 | fold_stmt_r_data.inside_addr_expr_p = &inside_addr_expr; | |
38965eb2 | 2993 | |
726a989a RB |
2994 | memset (&wi, 0, sizeof (wi)); |
2995 | wi.info = &fold_stmt_r_data; | |
2996 | ||
2997 | /* Fold the individual operands. | |
2998 | For example, fold instances of *&VAR into VAR, etc. | |
38965eb2 | 2999 | |
726a989a RB |
3000 | It appears that, at one time, maybe_fold_stmt_indirect |
3001 | would cause the walk to return non-null in order to | |
3002 | signal that the entire statement should be replaced with | |
3003 | a call to _builtin_trap. This functionality is currently | |
3004 | disabled, as noted in a FIXME, and cannot be supported here. */ | |
3005 | res = walk_gimple_op (stmt, fold_stmt_r, &wi); | |
3006 | gcc_assert (!res); | |
38965eb2 | 3007 | |
726a989a RB |
3008 | /* Fold the main computation performed by the statement. */ |
3009 | switch (gimple_code (stmt)) | |
3010 | { | |
3011 | case GIMPLE_ASSIGN: | |
3012 | { | |
3013 | unsigned old_num_ops; | |
3014 | tree new_rhs; | |
3015 | old_num_ops = gimple_num_ops (stmt); | |
3016 | si = gsi_for_stmt (stmt); | |
3017 | new_rhs = fold_gimple_assign (&si); | |
3018 | if (new_rhs != NULL_TREE | |
3019 | && get_gimple_rhs_num_ops (TREE_CODE (new_rhs)) < old_num_ops) | |
3020 | { | |
3021 | gimple_assign_set_rhs_from_tree (&si, new_rhs); | |
3022 | changed = true; | |
3023 | } | |
3024 | gcc_assert (gsi_stmt (si) == stmt); | |
3025 | break; | |
3026 | } | |
3027 | case GIMPLE_COND: | |
3028 | changed |= fold_gimple_cond (stmt); | |
3029 | break; | |
38965eb2 | 3030 | |
726a989a RB |
3031 | default: |
3032 | break; | |
3033 | } | |
38965eb2 ZD |
3034 | |
3035 | return changed; | |
3036 | } | |
726a989a | 3037 | |
cb8e078d JJ |
3038 | /* Try to optimize out __builtin_stack_restore. Optimize it out |
3039 | if there is another __builtin_stack_restore in the same basic | |
3040 | block and no calls or ASM_EXPRs are in between, or if this block's | |
3041 | only outgoing edge is to EXIT_BLOCK and there are no calls or | |
3042 | ASM_EXPRs after this __builtin_stack_restore. */ | |
3043 | ||
3044 | static tree | |
726a989a | 3045 | optimize_stack_restore (gimple_stmt_iterator i) |
cb8e078d | 3046 | { |
726a989a RB |
3047 | tree callee, rhs; |
3048 | gimple stmt, stack_save; | |
3049 | gimple_stmt_iterator stack_save_gsi; | |
3050 | ||
3051 | basic_block bb = gsi_bb (i); | |
3052 | gimple call = gsi_stmt (i); | |
cb8e078d | 3053 | |
726a989a RB |
3054 | if (gimple_code (call) != GIMPLE_CALL |
3055 | || gimple_call_num_args (call) != 1 | |
3056 | || TREE_CODE (gimple_call_arg (call, 0)) != SSA_NAME | |
3057 | || !POINTER_TYPE_P (TREE_TYPE (gimple_call_arg (call, 0)))) | |
cb8e078d JJ |
3058 | return NULL_TREE; |
3059 | ||
726a989a | 3060 | for (gsi_next (&i); !gsi_end_p (i); gsi_next (&i)) |
cb8e078d | 3061 | { |
726a989a RB |
3062 | stmt = gsi_stmt (i); |
3063 | if (gimple_code (stmt) == GIMPLE_ASM) | |
cb8e078d | 3064 | return NULL_TREE; |
726a989a | 3065 | if (gimple_code (stmt) != GIMPLE_CALL) |
cb8e078d JJ |
3066 | continue; |
3067 | ||
726a989a | 3068 | callee = gimple_call_fndecl (stmt); |
cb8e078d JJ |
3069 | if (!callee || DECL_BUILT_IN_CLASS (callee) != BUILT_IN_NORMAL) |
3070 | return NULL_TREE; | |
3071 | ||
3072 | if (DECL_FUNCTION_CODE (callee) == BUILT_IN_STACK_RESTORE) | |
3073 | break; | |
3074 | } | |
3075 | ||
726a989a | 3076 | if (gsi_end_p (i) |
cb8e078d JJ |
3077 | && (! single_succ_p (bb) |
3078 | || single_succ_edge (bb)->dest != EXIT_BLOCK_PTR)) | |
3079 | return NULL_TREE; | |
3080 | ||
726a989a RB |
3081 | stack_save = SSA_NAME_DEF_STMT (gimple_call_arg (call, 0)); |
3082 | if (gimple_code (stack_save) != GIMPLE_CALL | |
3083 | || gimple_call_lhs (stack_save) != gimple_call_arg (call, 0) | |
3084 | || stmt_could_throw_p (stack_save) | |
3085 | || !has_single_use (gimple_call_arg (call, 0))) | |
cb8e078d JJ |
3086 | return NULL_TREE; |
3087 | ||
726a989a | 3088 | callee = gimple_call_fndecl (stack_save); |
cb8e078d JJ |
3089 | if (!callee |
3090 | || DECL_BUILT_IN_CLASS (callee) != BUILT_IN_NORMAL | |
3091 | || DECL_FUNCTION_CODE (callee) != BUILT_IN_STACK_SAVE | |
726a989a | 3092 | || gimple_call_num_args (stack_save) != 0) |
cb8e078d JJ |
3093 | return NULL_TREE; |
3094 | ||
726a989a RB |
3095 | stack_save_gsi = gsi_for_stmt (stack_save); |
3096 | push_stmt_changes (gsi_stmt_ptr (&stack_save_gsi)); | |
3097 | rhs = build_int_cst (TREE_TYPE (gimple_call_arg (call, 0)), 0); | |
3098 | if (!update_call_from_tree (&stack_save_gsi, rhs)) | |
cb8e078d | 3099 | { |
726a989a | 3100 | discard_stmt_changes (gsi_stmt_ptr (&stack_save_gsi)); |
cb8e078d JJ |
3101 | return NULL_TREE; |
3102 | } | |
726a989a | 3103 | pop_stmt_changes (gsi_stmt_ptr (&stack_save_gsi)); |
cb8e078d | 3104 | |
726a989a | 3105 | /* No effect, so the statement will be deleted. */ |
cb8e078d JJ |
3106 | return integer_zero_node; |
3107 | } | |
726a989a | 3108 | |
d7bd8aeb JJ |
3109 | /* If va_list type is a simple pointer and nothing special is needed, |
3110 | optimize __builtin_va_start (&ap, 0) into ap = __builtin_next_arg (0), | |
3111 | __builtin_va_end (&ap) out as NOP and __builtin_va_copy into a simple | |
3112 | pointer assignment. */ | |
3113 | ||
3114 | static tree | |
726a989a | 3115 | optimize_stdarg_builtin (gimple call) |
d7bd8aeb | 3116 | { |
35cbb299 | 3117 | tree callee, lhs, rhs, cfun_va_list; |
d7bd8aeb JJ |
3118 | bool va_list_simple_ptr; |
3119 | ||
726a989a | 3120 | if (gimple_code (call) != GIMPLE_CALL) |
d7bd8aeb JJ |
3121 | return NULL_TREE; |
3122 | ||
726a989a | 3123 | callee = gimple_call_fndecl (call); |
35cbb299 KT |
3124 | |
3125 | cfun_va_list = targetm.fn_abi_va_list (callee); | |
3126 | va_list_simple_ptr = POINTER_TYPE_P (cfun_va_list) | |
3127 | && (TREE_TYPE (cfun_va_list) == void_type_node | |
3128 | || TREE_TYPE (cfun_va_list) == char_type_node); | |
3129 | ||
d7bd8aeb JJ |
3130 | switch (DECL_FUNCTION_CODE (callee)) |
3131 | { | |
3132 | case BUILT_IN_VA_START: | |
3133 | if (!va_list_simple_ptr | |
3134 | || targetm.expand_builtin_va_start != NULL | |
726a989a | 3135 | || built_in_decls[BUILT_IN_NEXT_ARG] == NULL) |
d7bd8aeb JJ |
3136 | return NULL_TREE; |
3137 | ||
726a989a | 3138 | if (gimple_call_num_args (call) != 2) |
d7bd8aeb JJ |
3139 | return NULL_TREE; |
3140 | ||
726a989a | 3141 | lhs = gimple_call_arg (call, 0); |
d7bd8aeb JJ |
3142 | if (!POINTER_TYPE_P (TREE_TYPE (lhs)) |
3143 | || TYPE_MAIN_VARIANT (TREE_TYPE (TREE_TYPE (lhs))) | |
35cbb299 | 3144 | != TYPE_MAIN_VARIANT (cfun_va_list)) |
d7bd8aeb | 3145 | return NULL_TREE; |
726a989a | 3146 | |
d7bd8aeb JJ |
3147 | lhs = build_fold_indirect_ref (lhs); |
3148 | rhs = build_call_expr (built_in_decls[BUILT_IN_NEXT_ARG], | |
726a989a | 3149 | 1, integer_zero_node); |
d7bd8aeb JJ |
3150 | rhs = fold_convert (TREE_TYPE (lhs), rhs); |
3151 | return build2 (MODIFY_EXPR, TREE_TYPE (lhs), lhs, rhs); | |
3152 | ||
3153 | case BUILT_IN_VA_COPY: | |
3154 | if (!va_list_simple_ptr) | |
3155 | return NULL_TREE; | |
3156 | ||
726a989a | 3157 | if (gimple_call_num_args (call) != 2) |
d7bd8aeb JJ |
3158 | return NULL_TREE; |
3159 | ||
726a989a | 3160 | lhs = gimple_call_arg (call, 0); |
d7bd8aeb JJ |
3161 | if (!POINTER_TYPE_P (TREE_TYPE (lhs)) |
3162 | || TYPE_MAIN_VARIANT (TREE_TYPE (TREE_TYPE (lhs))) | |
35cbb299 | 3163 | != TYPE_MAIN_VARIANT (cfun_va_list)) |
d7bd8aeb JJ |
3164 | return NULL_TREE; |
3165 | ||
3166 | lhs = build_fold_indirect_ref (lhs); | |
726a989a | 3167 | rhs = gimple_call_arg (call, 1); |
d7bd8aeb | 3168 | if (TYPE_MAIN_VARIANT (TREE_TYPE (rhs)) |
35cbb299 | 3169 | != TYPE_MAIN_VARIANT (cfun_va_list)) |
d7bd8aeb JJ |
3170 | return NULL_TREE; |
3171 | ||
3172 | rhs = fold_convert (TREE_TYPE (lhs), rhs); | |
3173 | return build2 (MODIFY_EXPR, TREE_TYPE (lhs), lhs, rhs); | |
3174 | ||
3175 | case BUILT_IN_VA_END: | |
726a989a | 3176 | /* No effect, so the statement will be deleted. */ |
d7bd8aeb JJ |
3177 | return integer_zero_node; |
3178 | ||
3179 | default: | |
3180 | gcc_unreachable (); | |
3181 | } | |
3182 | } | |
726a989a | 3183 | |
b28b1600 JJ |
3184 | /* Convert EXPR into a GIMPLE value suitable for substitution on the |
3185 | RHS of an assignment. Insert the necessary statements before | |
726a989a RB |
3186 | iterator *SI_P. The statement at *SI_P, which must be a GIMPLE_CALL |
3187 | is replaced. If the call is expected to produces a result, then it | |
3188 | is replaced by an assignment of the new RHS to the result variable. | |
3189 | If the result is to be ignored, then the call is replaced by a | |
3190 | GIMPLE_NOP. */ | |
b28b1600 | 3191 | |
726a989a RB |
3192 | static void |
3193 | gimplify_and_update_call_from_tree (gimple_stmt_iterator *si_p, tree expr) | |
b28b1600 | 3194 | { |
726a989a RB |
3195 | tree lhs; |
3196 | tree tmp = NULL_TREE; /* Silence warning. */ | |
3197 | gimple stmt, new_stmt; | |
3198 | gimple_stmt_iterator i; | |
3199 | gimple_seq stmts = gimple_seq_alloc(); | |
d406b663 | 3200 | struct gimplify_ctx gctx; |
b28b1600 | 3201 | |
726a989a RB |
3202 | stmt = gsi_stmt (*si_p); |
3203 | ||
3204 | gcc_assert (is_gimple_call (stmt)); | |
3205 | ||
3206 | lhs = gimple_call_lhs (stmt); | |
3207 | ||
d406b663 | 3208 | push_gimplify_context (&gctx); |
726a989a RB |
3209 | |
3210 | if (lhs == NULL_TREE) | |
3211 | gimplify_and_add (expr, &stmts); | |
3212 | else | |
2e929cf3 | 3213 | tmp = get_initialized_tmp_var (expr, &stmts, NULL); |
726a989a | 3214 | |
b28b1600 JJ |
3215 | pop_gimplify_context (NULL); |
3216 | ||
726a989a RB |
3217 | if (gimple_has_location (stmt)) |
3218 | annotate_all_with_location (stmts, gimple_location (stmt)); | |
f47c96aa | 3219 | |
b28b1600 | 3220 | /* The replacement can expose previously unreferenced variables. */ |
726a989a RB |
3221 | for (i = gsi_start (stmts); !gsi_end_p (i); gsi_next (&i)) |
3222 | { | |
3223 | new_stmt = gsi_stmt (i); | |
3224 | find_new_referenced_vars (new_stmt); | |
3225 | gsi_insert_before (si_p, new_stmt, GSI_NEW_STMT); | |
3226 | mark_symbols_for_renaming (new_stmt); | |
3227 | gsi_next (si_p); | |
3228 | } | |
3229 | ||
3230 | if (lhs == NULL_TREE) | |
5006671f RG |
3231 | { |
3232 | new_stmt = gimple_build_nop (); | |
3233 | unlink_stmt_vdef (stmt); | |
3234 | release_defs (stmt); | |
3235 | } | |
726a989a | 3236 | else |
b28b1600 | 3237 | { |
726a989a | 3238 | new_stmt = gimple_build_assign (lhs, tmp); |
5006671f RG |
3239 | gimple_set_vuse (new_stmt, gimple_vuse (stmt)); |
3240 | gimple_set_vdef (new_stmt, gimple_vdef (stmt)); | |
726a989a | 3241 | move_ssa_defining_stmt_for_defs (new_stmt, stmt); |
b28b1600 JJ |
3242 | } |
3243 | ||
726a989a RB |
3244 | gimple_set_location (new_stmt, gimple_location (stmt)); |
3245 | gsi_replace (si_p, new_stmt, false); | |
b28b1600 JJ |
3246 | } |
3247 | ||
6de9cd9a DN |
3248 | /* A simple pass that attempts to fold all builtin functions. This pass |
3249 | is run after we've propagated as many constants as we can. */ | |
3250 | ||
c2924966 | 3251 | static unsigned int |
6de9cd9a DN |
3252 | execute_fold_all_builtins (void) |
3253 | { | |
a7d6ba24 | 3254 | bool cfg_changed = false; |
6de9cd9a | 3255 | basic_block bb; |
7b0e48fb DB |
3256 | unsigned int todoflags = 0; |
3257 | ||
6de9cd9a DN |
3258 | FOR_EACH_BB (bb) |
3259 | { | |
726a989a RB |
3260 | gimple_stmt_iterator i; |
3261 | for (i = gsi_start_bb (bb); !gsi_end_p (i); ) | |
6de9cd9a | 3262 | { |
726a989a | 3263 | gimple stmt, old_stmt; |
6de9cd9a | 3264 | tree callee, result; |
10a0d495 | 3265 | enum built_in_function fcode; |
6de9cd9a | 3266 | |
726a989a RB |
3267 | stmt = gsi_stmt (i); |
3268 | ||
3269 | if (gimple_code (stmt) != GIMPLE_CALL) | |
10a0d495 | 3270 | { |
726a989a | 3271 | gsi_next (&i); |
10a0d495 JJ |
3272 | continue; |
3273 | } | |
726a989a | 3274 | callee = gimple_call_fndecl (stmt); |
6de9cd9a | 3275 | if (!callee || DECL_BUILT_IN_CLASS (callee) != BUILT_IN_NORMAL) |
10a0d495 | 3276 | { |
726a989a | 3277 | gsi_next (&i); |
10a0d495 JJ |
3278 | continue; |
3279 | } | |
3280 | fcode = DECL_FUNCTION_CODE (callee); | |
6de9cd9a | 3281 | |
726a989a | 3282 | result = ccp_fold_builtin (stmt); |
53a8f709 UB |
3283 | |
3284 | if (result) | |
726a989a | 3285 | gimple_remove_stmt_histograms (cfun, stmt); |
53a8f709 | 3286 | |
6de9cd9a DN |
3287 | if (!result) |
3288 | switch (DECL_FUNCTION_CODE (callee)) | |
3289 | { | |
3290 | case BUILT_IN_CONSTANT_P: | |
3291 | /* Resolve __builtin_constant_p. If it hasn't been | |
3292 | folded to integer_one_node by now, it's fairly | |
3293 | certain that the value simply isn't constant. */ | |
726a989a | 3294 | result = integer_zero_node; |
6de9cd9a DN |
3295 | break; |
3296 | ||
cb8e078d | 3297 | case BUILT_IN_STACK_RESTORE: |
726a989a | 3298 | result = optimize_stack_restore (i); |
d7bd8aeb JJ |
3299 | if (result) |
3300 | break; | |
726a989a | 3301 | gsi_next (&i); |
d7bd8aeb JJ |
3302 | continue; |
3303 | ||
3304 | case BUILT_IN_VA_START: | |
3305 | case BUILT_IN_VA_END: | |
3306 | case BUILT_IN_VA_COPY: | |
3307 | /* These shouldn't be folded before pass_stdarg. */ | |
726a989a | 3308 | result = optimize_stdarg_builtin (stmt); |
cb8e078d JJ |
3309 | if (result) |
3310 | break; | |
3311 | /* FALLTHRU */ | |
3312 | ||
6de9cd9a | 3313 | default: |
726a989a | 3314 | gsi_next (&i); |
6de9cd9a DN |
3315 | continue; |
3316 | } | |
3317 | ||
3318 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
3319 | { | |
3320 | fprintf (dump_file, "Simplified\n "); | |
726a989a | 3321 | print_gimple_stmt (dump_file, stmt, 0, dump_flags); |
6de9cd9a DN |
3322 | } |
3323 | ||
726a989a RB |
3324 | old_stmt = stmt; |
3325 | push_stmt_changes (gsi_stmt_ptr (&i)); | |
cfaab3a9 | 3326 | |
726a989a | 3327 | if (!update_call_from_tree (&i, result)) |
4bad83f5 RG |
3328 | { |
3329 | gimplify_and_update_call_from_tree (&i, result); | |
3330 | todoflags |= TODO_update_address_taken; | |
3331 | } | |
cfaab3a9 | 3332 | |
726a989a RB |
3333 | stmt = gsi_stmt (i); |
3334 | pop_stmt_changes (gsi_stmt_ptr (&i)); | |
cfaab3a9 | 3335 | |
726a989a RB |
3336 | if (maybe_clean_or_replace_eh_stmt (old_stmt, stmt) |
3337 | && gimple_purge_dead_eh_edges (bb)) | |
a7d6ba24 | 3338 | cfg_changed = true; |
6de9cd9a DN |
3339 | |
3340 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
3341 | { | |
3342 | fprintf (dump_file, "to\n "); | |
726a989a | 3343 | print_gimple_stmt (dump_file, stmt, 0, dump_flags); |
6de9cd9a DN |
3344 | fprintf (dump_file, "\n"); |
3345 | } | |
10a0d495 JJ |
3346 | |
3347 | /* Retry the same statement if it changed into another | |
3348 | builtin, there might be new opportunities now. */ | |
726a989a | 3349 | if (gimple_code (stmt) != GIMPLE_CALL) |
10a0d495 | 3350 | { |
726a989a | 3351 | gsi_next (&i); |
10a0d495 JJ |
3352 | continue; |
3353 | } | |
726a989a | 3354 | callee = gimple_call_fndecl (stmt); |
10a0d495 | 3355 | if (!callee |
726a989a | 3356 | || DECL_BUILT_IN_CLASS (callee) != BUILT_IN_NORMAL |
10a0d495 | 3357 | || DECL_FUNCTION_CODE (callee) == fcode) |
726a989a | 3358 | gsi_next (&i); |
6de9cd9a DN |
3359 | } |
3360 | } | |
7b0e48fb | 3361 | |
a7d6ba24 | 3362 | /* Delete unreachable blocks. */ |
7b0e48fb DB |
3363 | if (cfg_changed) |
3364 | todoflags |= TODO_cleanup_cfg; | |
3365 | ||
3366 | return todoflags; | |
6de9cd9a DN |
3367 | } |
3368 | ||
750628d8 | 3369 | |
8ddbbcae | 3370 | struct gimple_opt_pass pass_fold_builtins = |
6de9cd9a | 3371 | { |
8ddbbcae JH |
3372 | { |
3373 | GIMPLE_PASS, | |
6de9cd9a DN |
3374 | "fab", /* name */ |
3375 | NULL, /* gate */ | |
3376 | execute_fold_all_builtins, /* execute */ | |
3377 | NULL, /* sub */ | |
3378 | NULL, /* next */ | |
3379 | 0, /* static_pass_number */ | |
3380 | 0, /* tv_id */ | |
7faade0f | 3381 | PROP_cfg | PROP_ssa, /* properties_required */ |
6de9cd9a DN |
3382 | 0, /* properties_provided */ |
3383 | 0, /* properties_destroyed */ | |
3384 | 0, /* todo_flags_start */ | |
b28b1600 JJ |
3385 | TODO_dump_func |
3386 | | TODO_verify_ssa | |
8ddbbcae JH |
3387 | | TODO_update_ssa /* todo_flags_finish */ |
3388 | } | |
6de9cd9a | 3389 | }; |