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cbdd87d4 | 1 | /* Statement simplification on GIMPLE. |
d1e082c2 | 2 | Copyright (C) 2010-2013 Free Software Foundation, Inc. |
cbdd87d4 RG |
3 | Split out from tree-ssa-ccp.c. |
4 | ||
5 | This file is part of GCC. | |
6 | ||
7 | GCC is free software; you can redistribute it and/or modify it | |
8 | under the terms of the GNU General Public License as published by the | |
9 | Free Software Foundation; either version 3, or (at your option) any | |
10 | later version. | |
11 | ||
12 | GCC is distributed in the hope that it will be useful, but WITHOUT | |
13 | ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or | |
14 | FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License | |
15 | for more details. | |
16 | ||
17 | You should have received a copy of the GNU General Public License | |
18 | along with GCC; see the file COPYING3. If not see | |
19 | <http://www.gnu.org/licenses/>. */ | |
20 | ||
21 | #include "config.h" | |
22 | #include "system.h" | |
23 | #include "coretypes.h" | |
24 | #include "tm.h" | |
25 | #include "tree.h" | |
26 | #include "flags.h" | |
cbdd87d4 | 27 | #include "function.h" |
7ee2468b | 28 | #include "dumpfile.h" |
442b4905 AM |
29 | #include "bitmap.h" |
30 | #include "gimple.h" | |
31 | #include "gimple-ssa.h" | |
32 | #include "tree-ssanames.h" | |
33 | #include "tree-into-ssa.h" | |
34 | #include "tree-dfa.h" | |
7a300452 | 35 | #include "tree-ssa.h" |
cbdd87d4 | 36 | #include "tree-ssa-propagate.h" |
cbdd87d4 | 37 | #include "target.h" |
450ad0cd JH |
38 | #include "ipa-utils.h" |
39 | #include "gimple-pretty-print.h" | |
4484a35a | 40 | #include "tree-ssa-address.h" |
cbdd87d4 | 41 | |
b3b9f3d0 | 42 | /* Return true when DECL can be referenced from current unit. |
c44c2088 JH |
43 | FROM_DECL (if non-null) specify constructor of variable DECL was taken from. |
44 | We can get declarations that are not possible to reference for various | |
45 | reasons: | |
1389294c | 46 | |
1389294c JH |
47 | 1) When analyzing C++ virtual tables. |
48 | C++ virtual tables do have known constructors even | |
49 | when they are keyed to other compilation unit. | |
50 | Those tables can contain pointers to methods and vars | |
51 | in other units. Those methods have both STATIC and EXTERNAL | |
52 | set. | |
53 | 2) In WHOPR mode devirtualization might lead to reference | |
54 | to method that was partitioned elsehwere. | |
55 | In this case we have static VAR_DECL or FUNCTION_DECL | |
56 | that has no corresponding callgraph/varpool node | |
b3b9f3d0 JH |
57 | declaring the body. |
58 | 3) COMDAT functions referred by external vtables that | |
3e89949e | 59 | we devirtualize only during final compilation stage. |
b3b9f3d0 JH |
60 | At this time we already decided that we will not output |
61 | the function body and thus we can't reference the symbol | |
62 | directly. */ | |
63 | ||
1389294c | 64 | static bool |
c44c2088 | 65 | can_refer_decl_in_current_unit_p (tree decl, tree from_decl) |
1389294c JH |
66 | { |
67 | struct varpool_node *vnode; | |
68 | struct cgraph_node *node; | |
5e20cdc9 | 69 | symtab_node *snode; |
c44c2088 | 70 | |
1632a686 JH |
71 | if (DECL_ABSTRACT (decl)) |
72 | return false; | |
73 | ||
74 | /* We are concerned only about static/external vars and functions. */ | |
75 | if ((!TREE_STATIC (decl) && !DECL_EXTERNAL (decl)) | |
76 | || (TREE_CODE (decl) != VAR_DECL && TREE_CODE (decl) != FUNCTION_DECL)) | |
77 | return true; | |
78 | ||
79 | /* Static objects can be referred only if they was not optimized out yet. */ | |
80 | if (!TREE_PUBLIC (decl) && !DECL_EXTERNAL (decl)) | |
81 | { | |
82 | snode = symtab_get_node (decl); | |
83 | if (!snode) | |
84 | return false; | |
85 | node = dyn_cast <cgraph_node> (snode); | |
86 | return !node || !node->global.inlined_to; | |
87 | } | |
88 | ||
6da8be89 | 89 | /* We will later output the initializer, so we can refer to it. |
c44c2088 JH |
90 | So we are concerned only when DECL comes from initializer of |
91 | external var. */ | |
92 | if (!from_decl | |
93 | || TREE_CODE (from_decl) != VAR_DECL | |
94 | || !DECL_EXTERNAL (from_decl) | |
6da8be89 | 95 | || (flag_ltrans |
67348ccc | 96 | && symtab_get_node (from_decl)->in_other_partition)) |
c44c2088 | 97 | return true; |
c44c2088 JH |
98 | /* We are folding reference from external vtable. The vtable may reffer |
99 | to a symbol keyed to other compilation unit. The other compilation | |
100 | unit may be in separate DSO and the symbol may be hidden. */ | |
101 | if (DECL_VISIBILITY_SPECIFIED (decl) | |
102 | && DECL_EXTERNAL (decl) | |
67348ccc | 103 | && (!(snode = symtab_get_node (decl)) || !snode->in_other_partition)) |
c44c2088 | 104 | return false; |
b3b9f3d0 JH |
105 | /* When function is public, we always can introduce new reference. |
106 | Exception are the COMDAT functions where introducing a direct | |
107 | reference imply need to include function body in the curren tunit. */ | |
108 | if (TREE_PUBLIC (decl) && !DECL_COMDAT (decl)) | |
109 | return true; | |
110 | /* We are not at ltrans stage; so don't worry about WHOPR. | |
111 | Also when still gimplifying all referred comdat functions will be | |
2e9bb6ba | 112 | produced. |
c44c2088 JH |
113 | |
114 | As observed in PR20991 for already optimized out comdat virtual functions | |
073a8998 | 115 | it may be tempting to not necessarily give up because the copy will be |
c44c2088 JH |
116 | output elsewhere when corresponding vtable is output. |
117 | This is however not possible - ABI specify that COMDATs are output in | |
118 | units where they are used and when the other unit was compiled with LTO | |
119 | it is possible that vtable was kept public while the function itself | |
120 | was privatized. */ | |
b3b9f3d0 JH |
121 | if (!flag_ltrans && (!DECL_COMDAT (decl) || !cgraph_function_flags_ready)) |
122 | return true; | |
c44c2088 JH |
123 | |
124 | /* OK we are seeing either COMDAT or static variable. In this case we must | |
125 | check that the definition is still around so we can refer it. */ | |
1389294c JH |
126 | if (TREE_CODE (decl) == FUNCTION_DECL) |
127 | { | |
128 | node = cgraph_get_node (decl); | |
b3b9f3d0 JH |
129 | /* Check that we still have function body and that we didn't took |
130 | the decision to eliminate offline copy of the function yet. | |
131 | The second is important when devirtualization happens during final | |
132 | compilation stage when making a new reference no longer makes callee | |
133 | to be compiled. */ | |
67348ccc | 134 | if (!node || !node->definition || node->global.inlined_to) |
c44c2088 JH |
135 | { |
136 | gcc_checking_assert (!TREE_ASM_WRITTEN (decl)); | |
137 | return false; | |
138 | } | |
1389294c JH |
139 | } |
140 | else if (TREE_CODE (decl) == VAR_DECL) | |
141 | { | |
142 | vnode = varpool_get_node (decl); | |
67348ccc | 143 | if (!vnode || !vnode->definition) |
c44c2088 JH |
144 | { |
145 | gcc_checking_assert (!TREE_ASM_WRITTEN (decl)); | |
146 | return false; | |
147 | } | |
1389294c | 148 | } |
b3b9f3d0 | 149 | return true; |
1389294c JH |
150 | } |
151 | ||
0038d4e0 | 152 | /* CVAL is value taken from DECL_INITIAL of variable. Try to transform it into |
c44c2088 JH |
153 | acceptable form for is_gimple_min_invariant. |
154 | FROM_DECL (if non-NULL) specify variable whose constructor contains CVAL. */ | |
17f39a39 JH |
155 | |
156 | tree | |
c44c2088 | 157 | canonicalize_constructor_val (tree cval, tree from_decl) |
17f39a39 | 158 | { |
50619002 EB |
159 | tree orig_cval = cval; |
160 | STRIP_NOPS (cval); | |
315f5f1b RG |
161 | if (TREE_CODE (cval) == POINTER_PLUS_EXPR |
162 | && TREE_CODE (TREE_OPERAND (cval, 1)) == INTEGER_CST) | |
17f39a39 | 163 | { |
315f5f1b RG |
164 | tree ptr = TREE_OPERAND (cval, 0); |
165 | if (is_gimple_min_invariant (ptr)) | |
166 | cval = build1_loc (EXPR_LOCATION (cval), | |
167 | ADDR_EXPR, TREE_TYPE (ptr), | |
168 | fold_build2 (MEM_REF, TREE_TYPE (TREE_TYPE (ptr)), | |
169 | ptr, | |
170 | fold_convert (ptr_type_node, | |
171 | TREE_OPERAND (cval, 1)))); | |
17f39a39 JH |
172 | } |
173 | if (TREE_CODE (cval) == ADDR_EXPR) | |
174 | { | |
5a27a197 RG |
175 | tree base = NULL_TREE; |
176 | if (TREE_CODE (TREE_OPERAND (cval, 0)) == COMPOUND_LITERAL_EXPR) | |
ca5f4331 MM |
177 | { |
178 | base = COMPOUND_LITERAL_EXPR_DECL (TREE_OPERAND (cval, 0)); | |
179 | if (base) | |
180 | TREE_OPERAND (cval, 0) = base; | |
181 | } | |
5a27a197 RG |
182 | else |
183 | base = get_base_address (TREE_OPERAND (cval, 0)); | |
7501ca28 RG |
184 | if (!base) |
185 | return NULL_TREE; | |
b3b9f3d0 | 186 | |
7501ca28 RG |
187 | if ((TREE_CODE (base) == VAR_DECL |
188 | || TREE_CODE (base) == FUNCTION_DECL) | |
c44c2088 | 189 | && !can_refer_decl_in_current_unit_p (base, from_decl)) |
1389294c | 190 | return NULL_TREE; |
7501ca28 | 191 | if (TREE_CODE (base) == VAR_DECL) |
46eb666a | 192 | TREE_ADDRESSABLE (base) = 1; |
7501ca28 RG |
193 | else if (TREE_CODE (base) == FUNCTION_DECL) |
194 | { | |
195 | /* Make sure we create a cgraph node for functions we'll reference. | |
196 | They can be non-existent if the reference comes from an entry | |
197 | of an external vtable for example. */ | |
66e6b990 | 198 | cgraph_get_create_real_symbol_node (base); |
7501ca28 | 199 | } |
0038d4e0 | 200 | /* Fixup types in global initializers. */ |
73aef89e RG |
201 | if (TREE_TYPE (TREE_TYPE (cval)) != TREE_TYPE (TREE_OPERAND (cval, 0))) |
202 | cval = build_fold_addr_expr (TREE_OPERAND (cval, 0)); | |
50619002 EB |
203 | |
204 | if (!useless_type_conversion_p (TREE_TYPE (orig_cval), TREE_TYPE (cval))) | |
205 | cval = fold_convert (TREE_TYPE (orig_cval), cval); | |
206 | return cval; | |
17f39a39 | 207 | } |
846abd0d RB |
208 | if (TREE_OVERFLOW_P (cval)) |
209 | return drop_tree_overflow (cval); | |
50619002 | 210 | return orig_cval; |
17f39a39 | 211 | } |
cbdd87d4 RG |
212 | |
213 | /* If SYM is a constant variable with known value, return the value. | |
214 | NULL_TREE is returned otherwise. */ | |
215 | ||
216 | tree | |
217 | get_symbol_constant_value (tree sym) | |
218 | { | |
6a6dac52 JH |
219 | tree val = ctor_for_folding (sym); |
220 | if (val != error_mark_node) | |
cbdd87d4 | 221 | { |
cbdd87d4 RG |
222 | if (val) |
223 | { | |
9d60be38 | 224 | val = canonicalize_constructor_val (unshare_expr (val), sym); |
1389294c | 225 | if (val && is_gimple_min_invariant (val)) |
17f39a39 | 226 | return val; |
1389294c JH |
227 | else |
228 | return NULL_TREE; | |
cbdd87d4 RG |
229 | } |
230 | /* Variables declared 'const' without an initializer | |
231 | have zero as the initializer if they may not be | |
232 | overridden at link or run time. */ | |
233 | if (!val | |
cbdd87d4 RG |
234 | && (INTEGRAL_TYPE_P (TREE_TYPE (sym)) |
235 | || SCALAR_FLOAT_TYPE_P (TREE_TYPE (sym)))) | |
e8160c9a | 236 | return build_zero_cst (TREE_TYPE (sym)); |
cbdd87d4 RG |
237 | } |
238 | ||
239 | return NULL_TREE; | |
240 | } | |
241 | ||
242 | ||
cbdd87d4 RG |
243 | |
244 | /* Subroutine of fold_stmt. We perform several simplifications of the | |
245 | memory reference tree EXPR and make sure to re-gimplify them properly | |
246 | after propagation of constant addresses. IS_LHS is true if the | |
247 | reference is supposed to be an lvalue. */ | |
248 | ||
249 | static tree | |
250 | maybe_fold_reference (tree expr, bool is_lhs) | |
251 | { | |
252 | tree *t = &expr; | |
17f39a39 | 253 | tree result; |
cbdd87d4 | 254 | |
f0eddb90 RG |
255 | if ((TREE_CODE (expr) == VIEW_CONVERT_EXPR |
256 | || TREE_CODE (expr) == REALPART_EXPR | |
257 | || TREE_CODE (expr) == IMAGPART_EXPR) | |
258 | && CONSTANT_CLASS_P (TREE_OPERAND (expr, 0))) | |
259 | return fold_unary_loc (EXPR_LOCATION (expr), | |
260 | TREE_CODE (expr), | |
261 | TREE_TYPE (expr), | |
262 | TREE_OPERAND (expr, 0)); | |
263 | else if (TREE_CODE (expr) == BIT_FIELD_REF | |
264 | && CONSTANT_CLASS_P (TREE_OPERAND (expr, 0))) | |
265 | return fold_ternary_loc (EXPR_LOCATION (expr), | |
266 | TREE_CODE (expr), | |
267 | TREE_TYPE (expr), | |
268 | TREE_OPERAND (expr, 0), | |
269 | TREE_OPERAND (expr, 1), | |
270 | TREE_OPERAND (expr, 2)); | |
271 | ||
272 | while (handled_component_p (*t)) | |
273 | t = &TREE_OPERAND (*t, 0); | |
cbdd87d4 | 274 | |
f0eddb90 RG |
275 | /* Canonicalize MEM_REFs invariant address operand. Do this first |
276 | to avoid feeding non-canonical MEM_REFs elsewhere. */ | |
277 | if (TREE_CODE (*t) == MEM_REF | |
278 | && !is_gimple_mem_ref_addr (TREE_OPERAND (*t, 0))) | |
cbdd87d4 | 279 | { |
f0eddb90 RG |
280 | bool volatile_p = TREE_THIS_VOLATILE (*t); |
281 | tree tem = fold_binary (MEM_REF, TREE_TYPE (*t), | |
282 | TREE_OPERAND (*t, 0), | |
283 | TREE_OPERAND (*t, 1)); | |
284 | if (tem) | |
285 | { | |
286 | TREE_THIS_VOLATILE (tem) = volatile_p; | |
287 | *t = tem; | |
288 | tem = maybe_fold_reference (expr, is_lhs); | |
289 | if (tem) | |
290 | return tem; | |
291 | return expr; | |
292 | } | |
cbdd87d4 RG |
293 | } |
294 | ||
f0eddb90 RG |
295 | if (!is_lhs |
296 | && (result = fold_const_aggregate_ref (expr)) | |
297 | && is_gimple_min_invariant (result)) | |
298 | return result; | |
cbdd87d4 | 299 | |
70f34814 RG |
300 | /* Fold back MEM_REFs to reference trees. */ |
301 | if (TREE_CODE (*t) == MEM_REF | |
302 | && TREE_CODE (TREE_OPERAND (*t, 0)) == ADDR_EXPR | |
303 | && integer_zerop (TREE_OPERAND (*t, 1)) | |
304 | && (TREE_THIS_VOLATILE (*t) | |
305 | == TREE_THIS_VOLATILE (TREE_OPERAND (TREE_OPERAND (*t, 0), 0))) | |
306 | && !TYPE_REF_CAN_ALIAS_ALL (TREE_TYPE (TREE_OPERAND (*t, 1))) | |
307 | && (TYPE_MAIN_VARIANT (TREE_TYPE (*t)) | |
308 | == TYPE_MAIN_VARIANT (TREE_TYPE (TREE_TYPE (TREE_OPERAND (*t, 1))))) | |
309 | /* We have to look out here to not drop a required conversion | |
310 | from the rhs to the lhs if is_lhs, but we don't have the | |
311 | rhs here to verify that. Thus require strict type | |
312 | compatibility. */ | |
313 | && types_compatible_p (TREE_TYPE (*t), | |
314 | TREE_TYPE (TREE_OPERAND | |
f0eddb90 | 315 | (TREE_OPERAND (*t, 0), 0)))) |
cbdd87d4 | 316 | { |
70f34814 RG |
317 | tree tem; |
318 | *t = TREE_OPERAND (TREE_OPERAND (*t, 0), 0); | |
319 | tem = maybe_fold_reference (expr, is_lhs); | |
320 | if (tem) | |
321 | return tem; | |
322 | return expr; | |
323 | } | |
4d948885 RG |
324 | else if (TREE_CODE (*t) == TARGET_MEM_REF) |
325 | { | |
326 | tree tem = maybe_fold_tmr (*t); | |
327 | if (tem) | |
328 | { | |
329 | *t = tem; | |
330 | tem = maybe_fold_reference (expr, is_lhs); | |
331 | if (tem) | |
332 | return tem; | |
333 | return expr; | |
334 | } | |
335 | } | |
cbdd87d4 RG |
336 | |
337 | return NULL_TREE; | |
338 | } | |
339 | ||
340 | ||
341 | /* Attempt to fold an assignment statement pointed-to by SI. Returns a | |
342 | replacement rhs for the statement or NULL_TREE if no simplification | |
343 | could be made. It is assumed that the operands have been previously | |
344 | folded. */ | |
345 | ||
346 | static tree | |
347 | fold_gimple_assign (gimple_stmt_iterator *si) | |
348 | { | |
349 | gimple stmt = gsi_stmt (*si); | |
350 | enum tree_code subcode = gimple_assign_rhs_code (stmt); | |
351 | location_t loc = gimple_location (stmt); | |
352 | ||
353 | tree result = NULL_TREE; | |
354 | ||
355 | switch (get_gimple_rhs_class (subcode)) | |
356 | { | |
357 | case GIMPLE_SINGLE_RHS: | |
358 | { | |
359 | tree rhs = gimple_assign_rhs1 (stmt); | |
360 | ||
4e71066d | 361 | if (REFERENCE_CLASS_P (rhs)) |
cbdd87d4 RG |
362 | return maybe_fold_reference (rhs, false); |
363 | ||
364 | else if (TREE_CODE (rhs) == ADDR_EXPR) | |
365 | { | |
70f34814 RG |
366 | tree ref = TREE_OPERAND (rhs, 0); |
367 | tree tem = maybe_fold_reference (ref, true); | |
368 | if (tem | |
369 | && TREE_CODE (tem) == MEM_REF | |
370 | && integer_zerop (TREE_OPERAND (tem, 1))) | |
371 | result = fold_convert (TREE_TYPE (rhs), TREE_OPERAND (tem, 0)); | |
372 | else if (tem) | |
cbdd87d4 RG |
373 | result = fold_convert (TREE_TYPE (rhs), |
374 | build_fold_addr_expr_loc (loc, tem)); | |
70f34814 RG |
375 | else if (TREE_CODE (ref) == MEM_REF |
376 | && integer_zerop (TREE_OPERAND (ref, 1))) | |
377 | result = fold_convert (TREE_TYPE (rhs), TREE_OPERAND (ref, 0)); | |
cbdd87d4 RG |
378 | } |
379 | ||
380 | else if (TREE_CODE (rhs) == CONSTRUCTOR | |
381 | && TREE_CODE (TREE_TYPE (rhs)) == VECTOR_TYPE | |
382 | && (CONSTRUCTOR_NELTS (rhs) | |
383 | == TYPE_VECTOR_SUBPARTS (TREE_TYPE (rhs)))) | |
384 | { | |
385 | /* Fold a constant vector CONSTRUCTOR to VECTOR_CST. */ | |
386 | unsigned i; | |
387 | tree val; | |
388 | ||
389 | FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (rhs), i, val) | |
390 | if (TREE_CODE (val) != INTEGER_CST | |
391 | && TREE_CODE (val) != REAL_CST | |
392 | && TREE_CODE (val) != FIXED_CST) | |
393 | return NULL_TREE; | |
394 | ||
395 | return build_vector_from_ctor (TREE_TYPE (rhs), | |
396 | CONSTRUCTOR_ELTS (rhs)); | |
397 | } | |
398 | ||
399 | else if (DECL_P (rhs)) | |
9d60be38 | 400 | return get_symbol_constant_value (rhs); |
cbdd87d4 RG |
401 | |
402 | /* If we couldn't fold the RHS, hand over to the generic | |
403 | fold routines. */ | |
404 | if (result == NULL_TREE) | |
405 | result = fold (rhs); | |
406 | ||
407 | /* Strip away useless type conversions. Both the NON_LVALUE_EXPR | |
408 | that may have been added by fold, and "useless" type | |
409 | conversions that might now be apparent due to propagation. */ | |
410 | STRIP_USELESS_TYPE_CONVERSION (result); | |
411 | ||
412 | if (result != rhs && valid_gimple_rhs_p (result)) | |
413 | return result; | |
414 | ||
415 | return NULL_TREE; | |
416 | } | |
417 | break; | |
418 | ||
419 | case GIMPLE_UNARY_RHS: | |
420 | { | |
421 | tree rhs = gimple_assign_rhs1 (stmt); | |
422 | ||
423 | result = fold_unary_loc (loc, subcode, gimple_expr_type (stmt), rhs); | |
424 | if (result) | |
425 | { | |
426 | /* If the operation was a conversion do _not_ mark a | |
427 | resulting constant with TREE_OVERFLOW if the original | |
428 | constant was not. These conversions have implementation | |
429 | defined behavior and retaining the TREE_OVERFLOW flag | |
430 | here would confuse later passes such as VRP. */ | |
431 | if (CONVERT_EXPR_CODE_P (subcode) | |
432 | && TREE_CODE (result) == INTEGER_CST | |
433 | && TREE_CODE (rhs) == INTEGER_CST) | |
434 | TREE_OVERFLOW (result) = TREE_OVERFLOW (rhs); | |
435 | ||
436 | STRIP_USELESS_TYPE_CONVERSION (result); | |
437 | if (valid_gimple_rhs_p (result)) | |
438 | return result; | |
439 | } | |
cbdd87d4 RG |
440 | } |
441 | break; | |
442 | ||
443 | case GIMPLE_BINARY_RHS: | |
9b80d091 KT |
444 | /* Try to canonicalize for boolean-typed X the comparisons |
445 | X == 0, X == 1, X != 0, and X != 1. */ | |
315f5f1b RG |
446 | if (gimple_assign_rhs_code (stmt) == EQ_EXPR |
447 | || gimple_assign_rhs_code (stmt) == NE_EXPR) | |
9b80d091 KT |
448 | { |
449 | tree lhs = gimple_assign_lhs (stmt); | |
450 | tree op1 = gimple_assign_rhs1 (stmt); | |
451 | tree op2 = gimple_assign_rhs2 (stmt); | |
452 | tree type = TREE_TYPE (op1); | |
453 | ||
454 | /* Check whether the comparison operands are of the same boolean | |
455 | type as the result type is. | |
456 | Check that second operand is an integer-constant with value | |
457 | one or zero. */ | |
458 | if (TREE_CODE (op2) == INTEGER_CST | |
459 | && (integer_zerop (op2) || integer_onep (op2)) | |
460 | && useless_type_conversion_p (TREE_TYPE (lhs), type)) | |
461 | { | |
462 | enum tree_code cmp_code = gimple_assign_rhs_code (stmt); | |
463 | bool is_logical_not = false; | |
464 | ||
465 | /* X == 0 and X != 1 is a logical-not.of X | |
466 | X == 1 and X != 0 is X */ | |
467 | if ((cmp_code == EQ_EXPR && integer_zerop (op2)) | |
468 | || (cmp_code == NE_EXPR && integer_onep (op2))) | |
469 | is_logical_not = true; | |
470 | ||
471 | if (is_logical_not == false) | |
472 | result = op1; | |
473 | /* Only for one-bit precision typed X the transformation | |
474 | !X -> ~X is valied. */ | |
475 | else if (TYPE_PRECISION (type) == 1) | |
476 | result = build1_loc (gimple_location (stmt), BIT_NOT_EXPR, | |
477 | type, op1); | |
478 | /* Otherwise we use !X -> X ^ 1. */ | |
479 | else | |
480 | result = build2_loc (gimple_location (stmt), BIT_XOR_EXPR, | |
481 | type, op1, build_int_cst (type, 1)); | |
482 | ||
483 | } | |
484 | } | |
cbdd87d4 RG |
485 | |
486 | if (!result) | |
487 | result = fold_binary_loc (loc, subcode, | |
5fbcc0ed RG |
488 | TREE_TYPE (gimple_assign_lhs (stmt)), |
489 | gimple_assign_rhs1 (stmt), | |
490 | gimple_assign_rhs2 (stmt)); | |
cbdd87d4 RG |
491 | |
492 | if (result) | |
493 | { | |
494 | STRIP_USELESS_TYPE_CONVERSION (result); | |
495 | if (valid_gimple_rhs_p (result)) | |
496 | return result; | |
cbdd87d4 RG |
497 | } |
498 | break; | |
499 | ||
0354c0c7 | 500 | case GIMPLE_TERNARY_RHS: |
4e71066d RG |
501 | /* Try to fold a conditional expression. */ |
502 | if (gimple_assign_rhs_code (stmt) == COND_EXPR) | |
503 | { | |
504 | tree op0 = gimple_assign_rhs1 (stmt); | |
505 | tree tem; | |
506 | bool set = false; | |
507 | location_t cond_loc = gimple_location (stmt); | |
508 | ||
509 | if (COMPARISON_CLASS_P (op0)) | |
510 | { | |
511 | fold_defer_overflow_warnings (); | |
512 | tem = fold_binary_loc (cond_loc, | |
513 | TREE_CODE (op0), TREE_TYPE (op0), | |
514 | TREE_OPERAND (op0, 0), | |
515 | TREE_OPERAND (op0, 1)); | |
516 | /* This is actually a conditional expression, not a GIMPLE | |
517 | conditional statement, however, the valid_gimple_rhs_p | |
518 | test still applies. */ | |
519 | set = (tem && is_gimple_condexpr (tem) | |
520 | && valid_gimple_rhs_p (tem)); | |
521 | fold_undefer_overflow_warnings (set, stmt, 0); | |
522 | } | |
523 | else if (is_gimple_min_invariant (op0)) | |
524 | { | |
525 | tem = op0; | |
526 | set = true; | |
527 | } | |
528 | else | |
529 | return NULL_TREE; | |
530 | ||
531 | if (set) | |
532 | result = fold_build3_loc (cond_loc, COND_EXPR, | |
533 | TREE_TYPE (gimple_assign_lhs (stmt)), tem, | |
534 | gimple_assign_rhs2 (stmt), | |
535 | gimple_assign_rhs3 (stmt)); | |
536 | } | |
537 | ||
538 | if (!result) | |
539 | result = fold_ternary_loc (loc, subcode, | |
540 | TREE_TYPE (gimple_assign_lhs (stmt)), | |
541 | gimple_assign_rhs1 (stmt), | |
542 | gimple_assign_rhs2 (stmt), | |
543 | gimple_assign_rhs3 (stmt)); | |
0354c0c7 BS |
544 | |
545 | if (result) | |
546 | { | |
547 | STRIP_USELESS_TYPE_CONVERSION (result); | |
548 | if (valid_gimple_rhs_p (result)) | |
549 | return result; | |
0354c0c7 BS |
550 | } |
551 | break; | |
552 | ||
cbdd87d4 RG |
553 | case GIMPLE_INVALID_RHS: |
554 | gcc_unreachable (); | |
555 | } | |
556 | ||
557 | return NULL_TREE; | |
558 | } | |
559 | ||
560 | /* Attempt to fold a conditional statement. Return true if any changes were | |
561 | made. We only attempt to fold the condition expression, and do not perform | |
562 | any transformation that would require alteration of the cfg. It is | |
563 | assumed that the operands have been previously folded. */ | |
564 | ||
565 | static bool | |
566 | fold_gimple_cond (gimple stmt) | |
567 | { | |
568 | tree result = fold_binary_loc (gimple_location (stmt), | |
569 | gimple_cond_code (stmt), | |
570 | boolean_type_node, | |
571 | gimple_cond_lhs (stmt), | |
572 | gimple_cond_rhs (stmt)); | |
573 | ||
574 | if (result) | |
575 | { | |
576 | STRIP_USELESS_TYPE_CONVERSION (result); | |
577 | if (is_gimple_condexpr (result) && valid_gimple_rhs_p (result)) | |
578 | { | |
579 | gimple_cond_set_condition_from_tree (stmt, result); | |
580 | return true; | |
581 | } | |
582 | } | |
583 | ||
584 | return false; | |
585 | } | |
586 | ||
587 | /* Convert EXPR into a GIMPLE value suitable for substitution on the | |
588 | RHS of an assignment. Insert the necessary statements before | |
589 | iterator *SI_P. The statement at *SI_P, which must be a GIMPLE_CALL | |
590 | is replaced. If the call is expected to produces a result, then it | |
591 | is replaced by an assignment of the new RHS to the result variable. | |
592 | If the result is to be ignored, then the call is replaced by a | |
fe2ef088 MM |
593 | GIMPLE_NOP. A proper VDEF chain is retained by making the first |
594 | VUSE and the last VDEF of the whole sequence be the same as the replaced | |
595 | statement and using new SSA names for stores in between. */ | |
cbdd87d4 RG |
596 | |
597 | void | |
598 | gimplify_and_update_call_from_tree (gimple_stmt_iterator *si_p, tree expr) | |
599 | { | |
600 | tree lhs; | |
cbdd87d4 RG |
601 | gimple stmt, new_stmt; |
602 | gimple_stmt_iterator i; | |
355a7673 | 603 | gimple_seq stmts = NULL; |
cbdd87d4 | 604 | struct gimplify_ctx gctx; |
e256dfce | 605 | gimple laststore; |
fe2ef088 | 606 | tree reaching_vuse; |
cbdd87d4 RG |
607 | |
608 | stmt = gsi_stmt (*si_p); | |
609 | ||
610 | gcc_assert (is_gimple_call (stmt)); | |
611 | ||
cbdd87d4 | 612 | push_gimplify_context (&gctx); |
21860814 | 613 | gctx.into_ssa = gimple_in_ssa_p (cfun); |
cbdd87d4 | 614 | |
e256dfce | 615 | lhs = gimple_call_lhs (stmt); |
cbdd87d4 | 616 | if (lhs == NULL_TREE) |
6e572326 RG |
617 | { |
618 | gimplify_and_add (expr, &stmts); | |
619 | /* We can end up with folding a memcpy of an empty class assignment | |
620 | which gets optimized away by C++ gimplification. */ | |
621 | if (gimple_seq_empty_p (stmts)) | |
622 | { | |
9fdc58de | 623 | pop_gimplify_context (NULL); |
6e572326 RG |
624 | if (gimple_in_ssa_p (cfun)) |
625 | { | |
626 | unlink_stmt_vdef (stmt); | |
627 | release_defs (stmt); | |
628 | } | |
77d19c72 | 629 | gsi_replace (si_p, gimple_build_nop (), true); |
6e572326 RG |
630 | return; |
631 | } | |
632 | } | |
cbdd87d4 | 633 | else |
e256dfce RG |
634 | { |
635 | tree tmp = get_initialized_tmp_var (expr, &stmts, NULL); | |
636 | new_stmt = gimple_build_assign (lhs, tmp); | |
637 | i = gsi_last (stmts); | |
638 | gsi_insert_after_without_update (&i, new_stmt, | |
639 | GSI_CONTINUE_LINKING); | |
640 | } | |
cbdd87d4 RG |
641 | |
642 | pop_gimplify_context (NULL); | |
643 | ||
644 | if (gimple_has_location (stmt)) | |
645 | annotate_all_with_location (stmts, gimple_location (stmt)); | |
646 | ||
e256dfce RG |
647 | /* First iterate over the replacement statements backward, assigning |
648 | virtual operands to their defining statements. */ | |
649 | laststore = NULL; | |
650 | for (i = gsi_last (stmts); !gsi_end_p (i); gsi_prev (&i)) | |
651 | { | |
652 | new_stmt = gsi_stmt (i); | |
949e47e5 JJ |
653 | if ((gimple_assign_single_p (new_stmt) |
654 | && !is_gimple_reg (gimple_assign_lhs (new_stmt))) | |
655 | || (is_gimple_call (new_stmt) | |
656 | && (gimple_call_flags (new_stmt) | |
657 | & (ECF_NOVOPS | ECF_PURE | ECF_CONST | ECF_NORETURN)) == 0)) | |
e256dfce RG |
658 | { |
659 | tree vdef; | |
660 | if (!laststore) | |
661 | vdef = gimple_vdef (stmt); | |
662 | else | |
663 | vdef = make_ssa_name (gimple_vop (cfun), new_stmt); | |
664 | gimple_set_vdef (new_stmt, vdef); | |
52f26be4 | 665 | if (vdef && TREE_CODE (vdef) == SSA_NAME) |
e256dfce RG |
666 | SSA_NAME_DEF_STMT (vdef) = new_stmt; |
667 | laststore = new_stmt; | |
668 | } | |
669 | } | |
670 | ||
671 | /* Second iterate over the statements forward, assigning virtual | |
672 | operands to their uses. */ | |
e256dfce | 673 | reaching_vuse = gimple_vuse (stmt); |
cbdd87d4 RG |
674 | for (i = gsi_start (stmts); !gsi_end_p (i); gsi_next (&i)) |
675 | { | |
cbdd87d4 | 676 | new_stmt = gsi_stmt (i); |
a24ac460 RG |
677 | /* If the new statement possibly has a VUSE, update it with exact SSA |
678 | name we know will reach this one. */ | |
679 | if (gimple_has_mem_ops (new_stmt)) | |
e256dfce RG |
680 | gimple_set_vuse (new_stmt, reaching_vuse); |
681 | gimple_set_modified (new_stmt, true); | |
682 | if (gimple_vdef (new_stmt)) | |
683 | reaching_vuse = gimple_vdef (new_stmt); | |
cbdd87d4 RG |
684 | } |
685 | ||
e256dfce RG |
686 | /* If the new sequence does not do a store release the virtual |
687 | definition of the original statement. */ | |
688 | if (reaching_vuse | |
689 | && reaching_vuse == gimple_vuse (stmt)) | |
cbdd87d4 | 690 | { |
e256dfce RG |
691 | tree vdef = gimple_vdef (stmt); |
692 | if (vdef | |
693 | && TREE_CODE (vdef) == SSA_NAME) | |
fe2ef088 MM |
694 | { |
695 | unlink_stmt_vdef (stmt); | |
e256dfce | 696 | release_ssa_name (vdef); |
8a1561bc | 697 | } |
cbdd87d4 RG |
698 | } |
699 | ||
355a7673 MM |
700 | /* Finally replace the original statement with the sequence. */ |
701 | gsi_replace_with_seq (si_p, stmts, false); | |
cbdd87d4 RG |
702 | } |
703 | ||
704 | /* Return the string length, maximum string length or maximum value of | |
705 | ARG in LENGTH. | |
706 | If ARG is an SSA name variable, follow its use-def chains. If LENGTH | |
707 | is not NULL and, for TYPE == 0, its value is not equal to the length | |
708 | we determine or if we are unable to determine the length or value, | |
709 | return false. VISITED is a bitmap of visited variables. | |
710 | TYPE is 0 if string length should be returned, 1 for maximum string | |
711 | length and 2 for maximum value ARG can have. */ | |
712 | ||
713 | static bool | |
714 | get_maxval_strlen (tree arg, tree *length, bitmap visited, int type) | |
715 | { | |
716 | tree var, val; | |
717 | gimple def_stmt; | |
718 | ||
719 | if (TREE_CODE (arg) != SSA_NAME) | |
720 | { | |
cbdd87d4 | 721 | /* We can end up with &(*iftmp_1)[0] here as well, so handle it. */ |
763dc99d AP |
722 | if (TREE_CODE (arg) == ADDR_EXPR |
723 | && TREE_CODE (TREE_OPERAND (arg, 0)) == ARRAY_REF | |
724 | && integer_zerop (TREE_OPERAND (TREE_OPERAND (arg, 0), 1))) | |
cbdd87d4 RG |
725 | { |
726 | tree aop0 = TREE_OPERAND (TREE_OPERAND (arg, 0), 0); | |
727 | if (TREE_CODE (aop0) == INDIRECT_REF | |
728 | && TREE_CODE (TREE_OPERAND (aop0, 0)) == SSA_NAME) | |
729 | return get_maxval_strlen (TREE_OPERAND (aop0, 0), | |
730 | length, visited, type); | |
731 | } | |
732 | ||
733 | if (type == 2) | |
734 | { | |
735 | val = arg; | |
736 | if (TREE_CODE (val) != INTEGER_CST | |
737 | || tree_int_cst_sgn (val) < 0) | |
738 | return false; | |
739 | } | |
740 | else | |
741 | val = c_strlen (arg, 1); | |
742 | if (!val) | |
743 | return false; | |
744 | ||
745 | if (*length) | |
746 | { | |
747 | if (type > 0) | |
748 | { | |
749 | if (TREE_CODE (*length) != INTEGER_CST | |
750 | || TREE_CODE (val) != INTEGER_CST) | |
751 | return false; | |
752 | ||
753 | if (tree_int_cst_lt (*length, val)) | |
754 | *length = val; | |
755 | return true; | |
756 | } | |
757 | else if (simple_cst_equal (val, *length) != 1) | |
758 | return false; | |
759 | } | |
760 | ||
761 | *length = val; | |
762 | return true; | |
763 | } | |
764 | ||
491e0b9b RG |
765 | /* If ARG is registered for SSA update we cannot look at its defining |
766 | statement. */ | |
767 | if (name_registered_for_update_p (arg)) | |
768 | return false; | |
769 | ||
cbdd87d4 | 770 | /* If we were already here, break the infinite cycle. */ |
fcaa4ca4 | 771 | if (!bitmap_set_bit (visited, SSA_NAME_VERSION (arg))) |
cbdd87d4 | 772 | return true; |
cbdd87d4 RG |
773 | |
774 | var = arg; | |
775 | def_stmt = SSA_NAME_DEF_STMT (var); | |
776 | ||
777 | switch (gimple_code (def_stmt)) | |
778 | { | |
779 | case GIMPLE_ASSIGN: | |
780 | /* The RHS of the statement defining VAR must either have a | |
781 | constant length or come from another SSA_NAME with a constant | |
782 | length. */ | |
783 | if (gimple_assign_single_p (def_stmt) | |
784 | || gimple_assign_unary_nop_p (def_stmt)) | |
785 | { | |
786 | tree rhs = gimple_assign_rhs1 (def_stmt); | |
787 | return get_maxval_strlen (rhs, length, visited, type); | |
788 | } | |
763dc99d AP |
789 | else if (gimple_assign_rhs_code (def_stmt) == COND_EXPR) |
790 | { | |
791 | tree op2 = gimple_assign_rhs2 (def_stmt); | |
792 | tree op3 = gimple_assign_rhs3 (def_stmt); | |
793 | return get_maxval_strlen (op2, length, visited, type) | |
794 | && get_maxval_strlen (op3, length, visited, type); | |
795 | } | |
cbdd87d4 RG |
796 | return false; |
797 | ||
798 | case GIMPLE_PHI: | |
799 | { | |
800 | /* All the arguments of the PHI node must have the same constant | |
801 | length. */ | |
802 | unsigned i; | |
803 | ||
804 | for (i = 0; i < gimple_phi_num_args (def_stmt); i++) | |
805 | { | |
806 | tree arg = gimple_phi_arg (def_stmt, i)->def; | |
807 | ||
808 | /* If this PHI has itself as an argument, we cannot | |
809 | determine the string length of this argument. However, | |
810 | if we can find a constant string length for the other | |
811 | PHI args then we can still be sure that this is a | |
812 | constant string length. So be optimistic and just | |
813 | continue with the next argument. */ | |
814 | if (arg == gimple_phi_result (def_stmt)) | |
815 | continue; | |
816 | ||
817 | if (!get_maxval_strlen (arg, length, visited, type)) | |
818 | return false; | |
819 | } | |
820 | } | |
821 | return true; | |
822 | ||
823 | default: | |
824 | return false; | |
825 | } | |
826 | } | |
827 | ||
828 | ||
829 | /* Fold builtin call in statement STMT. Returns a simplified tree. | |
830 | We may return a non-constant expression, including another call | |
831 | to a different function and with different arguments, e.g., | |
832 | substituting memcpy for strcpy when the string length is known. | |
833 | Note that some builtins expand into inline code that may not | |
834 | be valid in GIMPLE. Callers must take care. */ | |
835 | ||
836 | tree | |
837 | gimple_fold_builtin (gimple stmt) | |
838 | { | |
839 | tree result, val[3]; | |
840 | tree callee, a; | |
841 | int arg_idx, type; | |
842 | bitmap visited; | |
843 | bool ignore; | |
844 | int nargs; | |
845 | location_t loc = gimple_location (stmt); | |
846 | ||
847 | gcc_assert (is_gimple_call (stmt)); | |
848 | ||
849 | ignore = (gimple_call_lhs (stmt) == NULL); | |
850 | ||
851 | /* First try the generic builtin folder. If that succeeds, return the | |
852 | result directly. */ | |
853 | result = fold_call_stmt (stmt, ignore); | |
854 | if (result) | |
855 | { | |
856 | if (ignore) | |
857 | STRIP_NOPS (result); | |
858 | return result; | |
859 | } | |
860 | ||
861 | /* Ignore MD builtins. */ | |
862 | callee = gimple_call_fndecl (stmt); | |
863 | if (DECL_BUILT_IN_CLASS (callee) == BUILT_IN_MD) | |
864 | return NULL_TREE; | |
865 | ||
e7f9dae0 JJ |
866 | /* Give up for always_inline inline builtins until they are |
867 | inlined. */ | |
868 | if (avoid_folding_inline_builtin (callee)) | |
869 | return NULL_TREE; | |
870 | ||
cbdd87d4 RG |
871 | /* If the builtin could not be folded, and it has no argument list, |
872 | we're done. */ | |
873 | nargs = gimple_call_num_args (stmt); | |
874 | if (nargs == 0) | |
875 | return NULL_TREE; | |
876 | ||
877 | /* Limit the work only for builtins we know how to simplify. */ | |
878 | switch (DECL_FUNCTION_CODE (callee)) | |
879 | { | |
880 | case BUILT_IN_STRLEN: | |
881 | case BUILT_IN_FPUTS: | |
882 | case BUILT_IN_FPUTS_UNLOCKED: | |
883 | arg_idx = 0; | |
884 | type = 0; | |
885 | break; | |
886 | case BUILT_IN_STRCPY: | |
887 | case BUILT_IN_STRNCPY: | |
888 | arg_idx = 1; | |
889 | type = 0; | |
890 | break; | |
891 | case BUILT_IN_MEMCPY_CHK: | |
892 | case BUILT_IN_MEMPCPY_CHK: | |
893 | case BUILT_IN_MEMMOVE_CHK: | |
894 | case BUILT_IN_MEMSET_CHK: | |
895 | case BUILT_IN_STRNCPY_CHK: | |
f3fc9b80 | 896 | case BUILT_IN_STPNCPY_CHK: |
cbdd87d4 RG |
897 | arg_idx = 2; |
898 | type = 2; | |
899 | break; | |
900 | case BUILT_IN_STRCPY_CHK: | |
901 | case BUILT_IN_STPCPY_CHK: | |
902 | arg_idx = 1; | |
903 | type = 1; | |
904 | break; | |
905 | case BUILT_IN_SNPRINTF_CHK: | |
906 | case BUILT_IN_VSNPRINTF_CHK: | |
907 | arg_idx = 1; | |
908 | type = 2; | |
909 | break; | |
910 | default: | |
911 | return NULL_TREE; | |
912 | } | |
913 | ||
914 | if (arg_idx >= nargs) | |
915 | return NULL_TREE; | |
916 | ||
917 | /* Try to use the dataflow information gathered by the CCP process. */ | |
918 | visited = BITMAP_ALLOC (NULL); | |
919 | bitmap_clear (visited); | |
920 | ||
921 | memset (val, 0, sizeof (val)); | |
922 | a = gimple_call_arg (stmt, arg_idx); | |
923 | if (!get_maxval_strlen (a, &val[arg_idx], visited, type)) | |
924 | val[arg_idx] = NULL_TREE; | |
925 | ||
926 | BITMAP_FREE (visited); | |
927 | ||
928 | result = NULL_TREE; | |
929 | switch (DECL_FUNCTION_CODE (callee)) | |
930 | { | |
931 | case BUILT_IN_STRLEN: | |
932 | if (val[0] && nargs == 1) | |
933 | { | |
934 | tree new_val = | |
935 | fold_convert (TREE_TYPE (gimple_call_lhs (stmt)), val[0]); | |
936 | ||
937 | /* If the result is not a valid gimple value, or not a cast | |
6e4da084 | 938 | of a valid gimple value, then we cannot use the result. */ |
cbdd87d4 | 939 | if (is_gimple_val (new_val) |
3dbe9454 | 940 | || (CONVERT_EXPR_P (new_val) |
cbdd87d4 RG |
941 | && is_gimple_val (TREE_OPERAND (new_val, 0)))) |
942 | return new_val; | |
943 | } | |
944 | break; | |
945 | ||
946 | case BUILT_IN_STRCPY: | |
947 | if (val[1] && is_gimple_val (val[1]) && nargs == 2) | |
948 | result = fold_builtin_strcpy (loc, callee, | |
949 | gimple_call_arg (stmt, 0), | |
950 | gimple_call_arg (stmt, 1), | |
951 | val[1]); | |
952 | break; | |
953 | ||
954 | case BUILT_IN_STRNCPY: | |
955 | if (val[1] && is_gimple_val (val[1]) && nargs == 3) | |
956 | result = fold_builtin_strncpy (loc, callee, | |
957 | gimple_call_arg (stmt, 0), | |
958 | gimple_call_arg (stmt, 1), | |
959 | gimple_call_arg (stmt, 2), | |
960 | val[1]); | |
961 | break; | |
962 | ||
963 | case BUILT_IN_FPUTS: | |
964 | if (nargs == 2) | |
965 | result = fold_builtin_fputs (loc, gimple_call_arg (stmt, 0), | |
966 | gimple_call_arg (stmt, 1), | |
967 | ignore, false, val[0]); | |
968 | break; | |
969 | ||
970 | case BUILT_IN_FPUTS_UNLOCKED: | |
971 | if (nargs == 2) | |
972 | result = fold_builtin_fputs (loc, gimple_call_arg (stmt, 0), | |
973 | gimple_call_arg (stmt, 1), | |
974 | ignore, true, val[0]); | |
975 | break; | |
976 | ||
977 | case BUILT_IN_MEMCPY_CHK: | |
978 | case BUILT_IN_MEMPCPY_CHK: | |
979 | case BUILT_IN_MEMMOVE_CHK: | |
980 | case BUILT_IN_MEMSET_CHK: | |
981 | if (val[2] && is_gimple_val (val[2]) && nargs == 4) | |
982 | result = fold_builtin_memory_chk (loc, callee, | |
983 | gimple_call_arg (stmt, 0), | |
984 | gimple_call_arg (stmt, 1), | |
985 | gimple_call_arg (stmt, 2), | |
986 | gimple_call_arg (stmt, 3), | |
987 | val[2], ignore, | |
988 | DECL_FUNCTION_CODE (callee)); | |
989 | break; | |
990 | ||
991 | case BUILT_IN_STRCPY_CHK: | |
992 | case BUILT_IN_STPCPY_CHK: | |
993 | if (val[1] && is_gimple_val (val[1]) && nargs == 3) | |
994 | result = fold_builtin_stxcpy_chk (loc, callee, | |
995 | gimple_call_arg (stmt, 0), | |
996 | gimple_call_arg (stmt, 1), | |
997 | gimple_call_arg (stmt, 2), | |
998 | val[1], ignore, | |
999 | DECL_FUNCTION_CODE (callee)); | |
1000 | break; | |
1001 | ||
1002 | case BUILT_IN_STRNCPY_CHK: | |
f3fc9b80 | 1003 | case BUILT_IN_STPNCPY_CHK: |
cbdd87d4 | 1004 | if (val[2] && is_gimple_val (val[2]) && nargs == 4) |
f3fc9b80 | 1005 | result = fold_builtin_stxncpy_chk (loc, gimple_call_arg (stmt, 0), |
cbdd87d4 RG |
1006 | gimple_call_arg (stmt, 1), |
1007 | gimple_call_arg (stmt, 2), | |
1008 | gimple_call_arg (stmt, 3), | |
f3fc9b80 RG |
1009 | val[2], ignore, |
1010 | DECL_FUNCTION_CODE (callee)); | |
cbdd87d4 RG |
1011 | break; |
1012 | ||
1013 | case BUILT_IN_SNPRINTF_CHK: | |
1014 | case BUILT_IN_VSNPRINTF_CHK: | |
1015 | if (val[1] && is_gimple_val (val[1])) | |
1016 | result = gimple_fold_builtin_snprintf_chk (stmt, val[1], | |
1017 | DECL_FUNCTION_CODE (callee)); | |
1018 | break; | |
1019 | ||
1020 | default: | |
1021 | gcc_unreachable (); | |
1022 | } | |
1023 | ||
1024 | if (result && ignore) | |
1025 | result = fold_ignored_result (result); | |
1026 | return result; | |
1027 | } | |
1028 | ||
1ae6fe9b | 1029 | |
49c471e3 MJ |
1030 | /* Return a binfo to be used for devirtualization of calls based on an object |
1031 | represented by a declaration (i.e. a global or automatically allocated one) | |
1032 | or NULL if it cannot be found or is not safe. CST is expected to be an | |
1033 | ADDR_EXPR of such object or the function will return NULL. Currently it is | |
c49bdb2e JH |
1034 | safe to use such binfo only if it has no base binfo (i.e. no ancestors) |
1035 | EXPECTED_TYPE is type of the class virtual belongs to. */ | |
49c471e3 MJ |
1036 | |
1037 | tree | |
c49bdb2e | 1038 | gimple_extract_devirt_binfo_from_cst (tree cst, tree expected_type) |
49c471e3 MJ |
1039 | { |
1040 | HOST_WIDE_INT offset, size, max_size; | |
c49bdb2e | 1041 | tree base, type, binfo; |
49c471e3 MJ |
1042 | bool last_artificial = false; |
1043 | ||
1044 | if (!flag_devirtualize | |
1045 | || TREE_CODE (cst) != ADDR_EXPR | |
1046 | || TREE_CODE (TREE_TYPE (TREE_TYPE (cst))) != RECORD_TYPE) | |
1047 | return NULL_TREE; | |
1048 | ||
1049 | cst = TREE_OPERAND (cst, 0); | |
49c471e3 MJ |
1050 | base = get_ref_base_and_extent (cst, &offset, &size, &max_size); |
1051 | type = TREE_TYPE (base); | |
1052 | if (!DECL_P (base) | |
1053 | || max_size == -1 | |
1054 | || max_size != size | |
1055 | || TREE_CODE (type) != RECORD_TYPE) | |
1056 | return NULL_TREE; | |
1057 | ||
1058 | /* Find the sub-object the constant actually refers to and mark whether it is | |
1059 | an artificial one (as opposed to a user-defined one). */ | |
1060 | while (true) | |
1061 | { | |
1062 | HOST_WIDE_INT pos, size; | |
1063 | tree fld; | |
1064 | ||
d84db1ed | 1065 | if (types_same_for_odr (type, expected_type)) |
49c471e3 MJ |
1066 | break; |
1067 | if (offset < 0) | |
1068 | return NULL_TREE; | |
1069 | ||
1070 | for (fld = TYPE_FIELDS (type); fld; fld = DECL_CHAIN (fld)) | |
1071 | { | |
1072 | if (TREE_CODE (fld) != FIELD_DECL) | |
1073 | continue; | |
1074 | ||
1075 | pos = int_bit_position (fld); | |
1076 | size = tree_low_cst (DECL_SIZE (fld), 1); | |
1077 | if (pos <= offset && (pos + size) > offset) | |
1078 | break; | |
1079 | } | |
1080 | if (!fld || TREE_CODE (TREE_TYPE (fld)) != RECORD_TYPE) | |
1081 | return NULL_TREE; | |
1082 | ||
1083 | last_artificial = DECL_ARTIFICIAL (fld); | |
1084 | type = TREE_TYPE (fld); | |
1085 | offset -= pos; | |
1086 | } | |
073a8998 | 1087 | /* Artificial sub-objects are ancestors, we do not want to use them for |
49c471e3 MJ |
1088 | devirtualization, at least not here. */ |
1089 | if (last_artificial) | |
1090 | return NULL_TREE; | |
1091 | binfo = TYPE_BINFO (type); | |
1092 | if (!binfo || BINFO_N_BASE_BINFOS (binfo) > 0) | |
1093 | return NULL_TREE; | |
1094 | else | |
1095 | return binfo; | |
1096 | } | |
1097 | ||
cbdd87d4 RG |
1098 | /* Attempt to fold a call statement referenced by the statement iterator GSI. |
1099 | The statement may be replaced by another statement, e.g., if the call | |
1100 | simplifies to a constant value. Return true if any changes were made. | |
1101 | It is assumed that the operands have been previously folded. */ | |
1102 | ||
e021c122 | 1103 | static bool |
ceeffab0 | 1104 | gimple_fold_call (gimple_stmt_iterator *gsi, bool inplace) |
cbdd87d4 RG |
1105 | { |
1106 | gimple stmt = gsi_stmt (*gsi); | |
3b45a007 | 1107 | tree callee; |
e021c122 RG |
1108 | bool changed = false; |
1109 | unsigned i; | |
cbdd87d4 | 1110 | |
e021c122 RG |
1111 | /* Fold *& in call arguments. */ |
1112 | for (i = 0; i < gimple_call_num_args (stmt); ++i) | |
1113 | if (REFERENCE_CLASS_P (gimple_call_arg (stmt, i))) | |
1114 | { | |
1115 | tree tmp = maybe_fold_reference (gimple_call_arg (stmt, i), false); | |
1116 | if (tmp) | |
1117 | { | |
1118 | gimple_call_set_arg (stmt, i, tmp); | |
1119 | changed = true; | |
1120 | } | |
1121 | } | |
3b45a007 RG |
1122 | |
1123 | /* Check for virtual calls that became direct calls. */ | |
1124 | callee = gimple_call_fn (stmt); | |
25583c4f | 1125 | if (callee && TREE_CODE (callee) == OBJ_TYPE_REF) |
3b45a007 | 1126 | { |
49c471e3 MJ |
1127 | if (gimple_call_addr_fndecl (OBJ_TYPE_REF_EXPR (callee)) != NULL_TREE) |
1128 | { | |
450ad0cd JH |
1129 | if (dump_file && virtual_method_call_p (callee) |
1130 | && !possible_polymorphic_call_target_p | |
1131 | (callee, cgraph_get_node (gimple_call_addr_fndecl | |
1132 | (OBJ_TYPE_REF_EXPR (callee))))) | |
1133 | { | |
1134 | fprintf (dump_file, | |
1135 | "Type inheritnace inconsistent devirtualization of "); | |
1136 | print_gimple_stmt (dump_file, stmt, 0, TDF_SLIM); | |
1137 | fprintf (dump_file, " to "); | |
1138 | print_generic_expr (dump_file, callee, TDF_SLIM); | |
1139 | fprintf (dump_file, "\n"); | |
1140 | } | |
1141 | ||
49c471e3 | 1142 | gimple_call_set_fn (stmt, OBJ_TYPE_REF_EXPR (callee)); |
e021c122 RG |
1143 | changed = true; |
1144 | } | |
1d5755ef | 1145 | else if (virtual_method_call_p (callee)) |
e021c122 RG |
1146 | { |
1147 | tree obj = OBJ_TYPE_REF_OBJECT (callee); | |
c49bdb2e JH |
1148 | tree binfo = gimple_extract_devirt_binfo_from_cst |
1149 | (obj, obj_type_ref_class (callee)); | |
e021c122 RG |
1150 | if (binfo) |
1151 | { | |
1152 | HOST_WIDE_INT token | |
1153 | = TREE_INT_CST_LOW (OBJ_TYPE_REF_TOKEN (callee)); | |
1154 | tree fndecl = gimple_get_virt_method_for_binfo (token, binfo); | |
1155 | if (fndecl) | |
1156 | { | |
450ad0cd JH |
1157 | #ifdef ENABLE_CHECKING |
1158 | gcc_assert (possible_polymorphic_call_target_p | |
1159 | (callee, cgraph_get_node (fndecl))); | |
1160 | ||
1161 | #endif | |
e021c122 RG |
1162 | gimple_call_set_fndecl (stmt, fndecl); |
1163 | changed = true; | |
1164 | } | |
1165 | } | |
49c471e3 | 1166 | } |
e021c122 | 1167 | } |
49c471e3 | 1168 | |
e021c122 RG |
1169 | if (inplace) |
1170 | return changed; | |
1171 | ||
1172 | /* Check for builtins that CCP can handle using information not | |
1173 | available in the generic fold routines. */ | |
89faf322 | 1174 | callee = gimple_call_fndecl (stmt); |
e021c122 RG |
1175 | if (callee && DECL_BUILT_IN (callee)) |
1176 | { | |
1177 | tree result = gimple_fold_builtin (stmt); | |
f6dbed32 | 1178 | if (result) |
e021c122 RG |
1179 | { |
1180 | if (!update_call_from_tree (gsi, result)) | |
1181 | gimplify_and_update_call_from_tree (gsi, result); | |
1182 | changed = true; | |
1183 | } | |
ea679d55 JG |
1184 | else if (DECL_BUILT_IN_CLASS (callee) == BUILT_IN_MD) |
1185 | changed |= targetm.gimple_fold_builtin (gsi); | |
3b45a007 RG |
1186 | } |
1187 | ||
e021c122 | 1188 | return changed; |
cbdd87d4 RG |
1189 | } |
1190 | ||
1191 | /* Worker for both fold_stmt and fold_stmt_inplace. The INPLACE argument | |
1192 | distinguishes both cases. */ | |
1193 | ||
1194 | static bool | |
1195 | fold_stmt_1 (gimple_stmt_iterator *gsi, bool inplace) | |
1196 | { | |
1197 | bool changed = false; | |
1198 | gimple stmt = gsi_stmt (*gsi); | |
1199 | unsigned i; | |
1200 | ||
1201 | /* Fold the main computation performed by the statement. */ | |
1202 | switch (gimple_code (stmt)) | |
1203 | { | |
1204 | case GIMPLE_ASSIGN: | |
1205 | { | |
1206 | unsigned old_num_ops = gimple_num_ops (stmt); | |
5fbcc0ed | 1207 | enum tree_code subcode = gimple_assign_rhs_code (stmt); |
cbdd87d4 | 1208 | tree lhs = gimple_assign_lhs (stmt); |
5fbcc0ed RG |
1209 | tree new_rhs; |
1210 | /* First canonicalize operand order. This avoids building new | |
1211 | trees if this is the only thing fold would later do. */ | |
1212 | if ((commutative_tree_code (subcode) | |
1213 | || commutative_ternary_tree_code (subcode)) | |
1214 | && tree_swap_operands_p (gimple_assign_rhs1 (stmt), | |
1215 | gimple_assign_rhs2 (stmt), false)) | |
1216 | { | |
1217 | tree tem = gimple_assign_rhs1 (stmt); | |
1218 | gimple_assign_set_rhs1 (stmt, gimple_assign_rhs2 (stmt)); | |
1219 | gimple_assign_set_rhs2 (stmt, tem); | |
1220 | changed = true; | |
1221 | } | |
1222 | new_rhs = fold_gimple_assign (gsi); | |
cbdd87d4 RG |
1223 | if (new_rhs |
1224 | && !useless_type_conversion_p (TREE_TYPE (lhs), | |
1225 | TREE_TYPE (new_rhs))) | |
1226 | new_rhs = fold_convert (TREE_TYPE (lhs), new_rhs); | |
1227 | if (new_rhs | |
1228 | && (!inplace | |
1229 | || get_gimple_rhs_num_ops (TREE_CODE (new_rhs)) < old_num_ops)) | |
1230 | { | |
1231 | gimple_assign_set_rhs_from_tree (gsi, new_rhs); | |
1232 | changed = true; | |
1233 | } | |
1234 | break; | |
1235 | } | |
1236 | ||
1237 | case GIMPLE_COND: | |
1238 | changed |= fold_gimple_cond (stmt); | |
1239 | break; | |
1240 | ||
1241 | case GIMPLE_CALL: | |
ceeffab0 | 1242 | changed |= gimple_fold_call (gsi, inplace); |
cbdd87d4 RG |
1243 | break; |
1244 | ||
1245 | case GIMPLE_ASM: | |
1246 | /* Fold *& in asm operands. */ | |
38384150 JJ |
1247 | { |
1248 | size_t noutputs; | |
1249 | const char **oconstraints; | |
1250 | const char *constraint; | |
1251 | bool allows_mem, allows_reg; | |
1252 | ||
1253 | noutputs = gimple_asm_noutputs (stmt); | |
1254 | oconstraints = XALLOCAVEC (const char *, noutputs); | |
1255 | ||
1256 | for (i = 0; i < gimple_asm_noutputs (stmt); ++i) | |
1257 | { | |
1258 | tree link = gimple_asm_output_op (stmt, i); | |
1259 | tree op = TREE_VALUE (link); | |
1260 | oconstraints[i] | |
1261 | = TREE_STRING_POINTER (TREE_VALUE (TREE_PURPOSE (link))); | |
1262 | if (REFERENCE_CLASS_P (op) | |
1263 | && (op = maybe_fold_reference (op, true)) != NULL_TREE) | |
1264 | { | |
1265 | TREE_VALUE (link) = op; | |
1266 | changed = true; | |
1267 | } | |
1268 | } | |
1269 | for (i = 0; i < gimple_asm_ninputs (stmt); ++i) | |
1270 | { | |
1271 | tree link = gimple_asm_input_op (stmt, i); | |
1272 | tree op = TREE_VALUE (link); | |
1273 | constraint | |
1274 | = TREE_STRING_POINTER (TREE_VALUE (TREE_PURPOSE (link))); | |
1275 | parse_input_constraint (&constraint, 0, 0, noutputs, 0, | |
1276 | oconstraints, &allows_mem, &allows_reg); | |
1277 | if (REFERENCE_CLASS_P (op) | |
1278 | && (op = maybe_fold_reference (op, !allows_reg && allows_mem)) | |
1279 | != NULL_TREE) | |
1280 | { | |
1281 | TREE_VALUE (link) = op; | |
1282 | changed = true; | |
1283 | } | |
1284 | } | |
1285 | } | |
cbdd87d4 RG |
1286 | break; |
1287 | ||
bd422c4a RG |
1288 | case GIMPLE_DEBUG: |
1289 | if (gimple_debug_bind_p (stmt)) | |
1290 | { | |
1291 | tree val = gimple_debug_bind_get_value (stmt); | |
1292 | if (val | |
1293 | && REFERENCE_CLASS_P (val)) | |
1294 | { | |
1295 | tree tem = maybe_fold_reference (val, false); | |
1296 | if (tem) | |
1297 | { | |
1298 | gimple_debug_bind_set_value (stmt, tem); | |
1299 | changed = true; | |
1300 | } | |
1301 | } | |
3e888a5e RG |
1302 | else if (val |
1303 | && TREE_CODE (val) == ADDR_EXPR) | |
1304 | { | |
1305 | tree ref = TREE_OPERAND (val, 0); | |
1306 | tree tem = maybe_fold_reference (ref, false); | |
1307 | if (tem) | |
1308 | { | |
1309 | tem = build_fold_addr_expr_with_type (tem, TREE_TYPE (val)); | |
1310 | gimple_debug_bind_set_value (stmt, tem); | |
1311 | changed = true; | |
1312 | } | |
1313 | } | |
bd422c4a RG |
1314 | } |
1315 | break; | |
1316 | ||
cbdd87d4 RG |
1317 | default:; |
1318 | } | |
1319 | ||
1320 | stmt = gsi_stmt (*gsi); | |
1321 | ||
37376165 RB |
1322 | /* Fold *& on the lhs. */ |
1323 | if (gimple_has_lhs (stmt)) | |
cbdd87d4 RG |
1324 | { |
1325 | tree lhs = gimple_get_lhs (stmt); | |
1326 | if (lhs && REFERENCE_CLASS_P (lhs)) | |
1327 | { | |
1328 | tree new_lhs = maybe_fold_reference (lhs, true); | |
1329 | if (new_lhs) | |
1330 | { | |
1331 | gimple_set_lhs (stmt, new_lhs); | |
1332 | changed = true; | |
1333 | } | |
1334 | } | |
1335 | } | |
1336 | ||
1337 | return changed; | |
1338 | } | |
1339 | ||
1340 | /* Fold the statement pointed to by GSI. In some cases, this function may | |
1341 | replace the whole statement with a new one. Returns true iff folding | |
1342 | makes any changes. | |
1343 | The statement pointed to by GSI should be in valid gimple form but may | |
1344 | be in unfolded state as resulting from for example constant propagation | |
1345 | which can produce *&x = 0. */ | |
1346 | ||
1347 | bool | |
1348 | fold_stmt (gimple_stmt_iterator *gsi) | |
1349 | { | |
1350 | return fold_stmt_1 (gsi, false); | |
1351 | } | |
1352 | ||
59401b92 | 1353 | /* Perform the minimal folding on statement *GSI. Only operations like |
cbdd87d4 RG |
1354 | *&x created by constant propagation are handled. The statement cannot |
1355 | be replaced with a new one. Return true if the statement was | |
1356 | changed, false otherwise. | |
59401b92 | 1357 | The statement *GSI should be in valid gimple form but may |
cbdd87d4 RG |
1358 | be in unfolded state as resulting from for example constant propagation |
1359 | which can produce *&x = 0. */ | |
1360 | ||
1361 | bool | |
59401b92 | 1362 | fold_stmt_inplace (gimple_stmt_iterator *gsi) |
cbdd87d4 | 1363 | { |
59401b92 RG |
1364 | gimple stmt = gsi_stmt (*gsi); |
1365 | bool changed = fold_stmt_1 (gsi, true); | |
1366 | gcc_assert (gsi_stmt (*gsi) == stmt); | |
cbdd87d4 RG |
1367 | return changed; |
1368 | } | |
1369 | ||
e89065a1 SL |
1370 | /* Canonicalize and possibly invert the boolean EXPR; return NULL_TREE |
1371 | if EXPR is null or we don't know how. | |
1372 | If non-null, the result always has boolean type. */ | |
1373 | ||
1374 | static tree | |
1375 | canonicalize_bool (tree expr, bool invert) | |
1376 | { | |
1377 | if (!expr) | |
1378 | return NULL_TREE; | |
1379 | else if (invert) | |
1380 | { | |
1381 | if (integer_nonzerop (expr)) | |
1382 | return boolean_false_node; | |
1383 | else if (integer_zerop (expr)) | |
1384 | return boolean_true_node; | |
1385 | else if (TREE_CODE (expr) == SSA_NAME) | |
1386 | return fold_build2 (EQ_EXPR, boolean_type_node, expr, | |
1387 | build_int_cst (TREE_TYPE (expr), 0)); | |
1388 | else if (TREE_CODE_CLASS (TREE_CODE (expr)) == tcc_comparison) | |
1389 | return fold_build2 (invert_tree_comparison (TREE_CODE (expr), false), | |
1390 | boolean_type_node, | |
1391 | TREE_OPERAND (expr, 0), | |
1392 | TREE_OPERAND (expr, 1)); | |
1393 | else | |
1394 | return NULL_TREE; | |
1395 | } | |
1396 | else | |
1397 | { | |
1398 | if (TREE_CODE (TREE_TYPE (expr)) == BOOLEAN_TYPE) | |
1399 | return expr; | |
1400 | if (integer_nonzerop (expr)) | |
1401 | return boolean_true_node; | |
1402 | else if (integer_zerop (expr)) | |
1403 | return boolean_false_node; | |
1404 | else if (TREE_CODE (expr) == SSA_NAME) | |
1405 | return fold_build2 (NE_EXPR, boolean_type_node, expr, | |
1406 | build_int_cst (TREE_TYPE (expr), 0)); | |
1407 | else if (TREE_CODE_CLASS (TREE_CODE (expr)) == tcc_comparison) | |
1408 | return fold_build2 (TREE_CODE (expr), | |
1409 | boolean_type_node, | |
1410 | TREE_OPERAND (expr, 0), | |
1411 | TREE_OPERAND (expr, 1)); | |
1412 | else | |
1413 | return NULL_TREE; | |
1414 | } | |
1415 | } | |
1416 | ||
1417 | /* Check to see if a boolean expression EXPR is logically equivalent to the | |
1418 | comparison (OP1 CODE OP2). Check for various identities involving | |
1419 | SSA_NAMEs. */ | |
1420 | ||
1421 | static bool | |
1422 | same_bool_comparison_p (const_tree expr, enum tree_code code, | |
1423 | const_tree op1, const_tree op2) | |
1424 | { | |
1425 | gimple s; | |
1426 | ||
1427 | /* The obvious case. */ | |
1428 | if (TREE_CODE (expr) == code | |
1429 | && operand_equal_p (TREE_OPERAND (expr, 0), op1, 0) | |
1430 | && operand_equal_p (TREE_OPERAND (expr, 1), op2, 0)) | |
1431 | return true; | |
1432 | ||
1433 | /* Check for comparing (name, name != 0) and the case where expr | |
1434 | is an SSA_NAME with a definition matching the comparison. */ | |
1435 | if (TREE_CODE (expr) == SSA_NAME | |
1436 | && TREE_CODE (TREE_TYPE (expr)) == BOOLEAN_TYPE) | |
1437 | { | |
1438 | if (operand_equal_p (expr, op1, 0)) | |
1439 | return ((code == NE_EXPR && integer_zerop (op2)) | |
1440 | || (code == EQ_EXPR && integer_nonzerop (op2))); | |
1441 | s = SSA_NAME_DEF_STMT (expr); | |
1442 | if (is_gimple_assign (s) | |
1443 | && gimple_assign_rhs_code (s) == code | |
1444 | && operand_equal_p (gimple_assign_rhs1 (s), op1, 0) | |
1445 | && operand_equal_p (gimple_assign_rhs2 (s), op2, 0)) | |
1446 | return true; | |
1447 | } | |
1448 | ||
1449 | /* If op1 is of the form (name != 0) or (name == 0), and the definition | |
1450 | of name is a comparison, recurse. */ | |
1451 | if (TREE_CODE (op1) == SSA_NAME | |
1452 | && TREE_CODE (TREE_TYPE (op1)) == BOOLEAN_TYPE) | |
1453 | { | |
1454 | s = SSA_NAME_DEF_STMT (op1); | |
1455 | if (is_gimple_assign (s) | |
1456 | && TREE_CODE_CLASS (gimple_assign_rhs_code (s)) == tcc_comparison) | |
1457 | { | |
1458 | enum tree_code c = gimple_assign_rhs_code (s); | |
1459 | if ((c == NE_EXPR && integer_zerop (op2)) | |
1460 | || (c == EQ_EXPR && integer_nonzerop (op2))) | |
1461 | return same_bool_comparison_p (expr, c, | |
1462 | gimple_assign_rhs1 (s), | |
1463 | gimple_assign_rhs2 (s)); | |
1464 | if ((c == EQ_EXPR && integer_zerop (op2)) | |
1465 | || (c == NE_EXPR && integer_nonzerop (op2))) | |
1466 | return same_bool_comparison_p (expr, | |
1467 | invert_tree_comparison (c, false), | |
1468 | gimple_assign_rhs1 (s), | |
1469 | gimple_assign_rhs2 (s)); | |
1470 | } | |
1471 | } | |
1472 | return false; | |
1473 | } | |
1474 | ||
1475 | /* Check to see if two boolean expressions OP1 and OP2 are logically | |
1476 | equivalent. */ | |
1477 | ||
1478 | static bool | |
1479 | same_bool_result_p (const_tree op1, const_tree op2) | |
1480 | { | |
1481 | /* Simple cases first. */ | |
1482 | if (operand_equal_p (op1, op2, 0)) | |
1483 | return true; | |
1484 | ||
1485 | /* Check the cases where at least one of the operands is a comparison. | |
1486 | These are a bit smarter than operand_equal_p in that they apply some | |
1487 | identifies on SSA_NAMEs. */ | |
1488 | if (TREE_CODE_CLASS (TREE_CODE (op2)) == tcc_comparison | |
1489 | && same_bool_comparison_p (op1, TREE_CODE (op2), | |
1490 | TREE_OPERAND (op2, 0), | |
1491 | TREE_OPERAND (op2, 1))) | |
1492 | return true; | |
1493 | if (TREE_CODE_CLASS (TREE_CODE (op1)) == tcc_comparison | |
1494 | && same_bool_comparison_p (op2, TREE_CODE (op1), | |
1495 | TREE_OPERAND (op1, 0), | |
1496 | TREE_OPERAND (op1, 1))) | |
1497 | return true; | |
1498 | ||
1499 | /* Default case. */ | |
1500 | return false; | |
1501 | } | |
1502 | ||
1503 | /* Forward declarations for some mutually recursive functions. */ | |
1504 | ||
1505 | static tree | |
1506 | and_comparisons_1 (enum tree_code code1, tree op1a, tree op1b, | |
1507 | enum tree_code code2, tree op2a, tree op2b); | |
1508 | static tree | |
1509 | and_var_with_comparison (tree var, bool invert, | |
1510 | enum tree_code code2, tree op2a, tree op2b); | |
1511 | static tree | |
1512 | and_var_with_comparison_1 (gimple stmt, | |
1513 | enum tree_code code2, tree op2a, tree op2b); | |
1514 | static tree | |
1515 | or_comparisons_1 (enum tree_code code1, tree op1a, tree op1b, | |
1516 | enum tree_code code2, tree op2a, tree op2b); | |
1517 | static tree | |
1518 | or_var_with_comparison (tree var, bool invert, | |
1519 | enum tree_code code2, tree op2a, tree op2b); | |
1520 | static tree | |
1521 | or_var_with_comparison_1 (gimple stmt, | |
1522 | enum tree_code code2, tree op2a, tree op2b); | |
1523 | ||
1524 | /* Helper function for and_comparisons_1: try to simplify the AND of the | |
1525 | ssa variable VAR with the comparison specified by (OP2A CODE2 OP2B). | |
1526 | If INVERT is true, invert the value of the VAR before doing the AND. | |
1527 | Return NULL_EXPR if we can't simplify this to a single expression. */ | |
1528 | ||
1529 | static tree | |
1530 | and_var_with_comparison (tree var, bool invert, | |
1531 | enum tree_code code2, tree op2a, tree op2b) | |
1532 | { | |
1533 | tree t; | |
1534 | gimple stmt = SSA_NAME_DEF_STMT (var); | |
1535 | ||
1536 | /* We can only deal with variables whose definitions are assignments. */ | |
1537 | if (!is_gimple_assign (stmt)) | |
1538 | return NULL_TREE; | |
1539 | ||
1540 | /* If we have an inverted comparison, apply DeMorgan's law and rewrite | |
1541 | !var AND (op2a code2 op2b) => !(var OR !(op2a code2 op2b)) | |
1542 | Then we only have to consider the simpler non-inverted cases. */ | |
1543 | if (invert) | |
1544 | t = or_var_with_comparison_1 (stmt, | |
1545 | invert_tree_comparison (code2, false), | |
1546 | op2a, op2b); | |
1547 | else | |
1548 | t = and_var_with_comparison_1 (stmt, code2, op2a, op2b); | |
1549 | return canonicalize_bool (t, invert); | |
1550 | } | |
1551 | ||
1552 | /* Try to simplify the AND of the ssa variable defined by the assignment | |
1553 | STMT with the comparison specified by (OP2A CODE2 OP2B). | |
1554 | Return NULL_EXPR if we can't simplify this to a single expression. */ | |
1555 | ||
1556 | static tree | |
1557 | and_var_with_comparison_1 (gimple stmt, | |
1558 | enum tree_code code2, tree op2a, tree op2b) | |
1559 | { | |
1560 | tree var = gimple_assign_lhs (stmt); | |
1561 | tree true_test_var = NULL_TREE; | |
1562 | tree false_test_var = NULL_TREE; | |
1563 | enum tree_code innercode = gimple_assign_rhs_code (stmt); | |
1564 | ||
1565 | /* Check for identities like (var AND (var == 0)) => false. */ | |
1566 | if (TREE_CODE (op2a) == SSA_NAME | |
1567 | && TREE_CODE (TREE_TYPE (var)) == BOOLEAN_TYPE) | |
1568 | { | |
1569 | if ((code2 == NE_EXPR && integer_zerop (op2b)) | |
1570 | || (code2 == EQ_EXPR && integer_nonzerop (op2b))) | |
1571 | { | |
1572 | true_test_var = op2a; | |
1573 | if (var == true_test_var) | |
1574 | return var; | |
1575 | } | |
1576 | else if ((code2 == EQ_EXPR && integer_zerop (op2b)) | |
1577 | || (code2 == NE_EXPR && integer_nonzerop (op2b))) | |
1578 | { | |
1579 | false_test_var = op2a; | |
1580 | if (var == false_test_var) | |
1581 | return boolean_false_node; | |
1582 | } | |
1583 | } | |
1584 | ||
1585 | /* If the definition is a comparison, recurse on it. */ | |
1586 | if (TREE_CODE_CLASS (innercode) == tcc_comparison) | |
1587 | { | |
1588 | tree t = and_comparisons_1 (innercode, | |
1589 | gimple_assign_rhs1 (stmt), | |
1590 | gimple_assign_rhs2 (stmt), | |
1591 | code2, | |
1592 | op2a, | |
1593 | op2b); | |
1594 | if (t) | |
1595 | return t; | |
1596 | } | |
1597 | ||
1598 | /* If the definition is an AND or OR expression, we may be able to | |
1599 | simplify by reassociating. */ | |
eb9820c0 KT |
1600 | if (TREE_CODE (TREE_TYPE (var)) == BOOLEAN_TYPE |
1601 | && (innercode == BIT_AND_EXPR || innercode == BIT_IOR_EXPR)) | |
e89065a1 SL |
1602 | { |
1603 | tree inner1 = gimple_assign_rhs1 (stmt); | |
1604 | tree inner2 = gimple_assign_rhs2 (stmt); | |
1605 | gimple s; | |
1606 | tree t; | |
1607 | tree partial = NULL_TREE; | |
eb9820c0 | 1608 | bool is_and = (innercode == BIT_AND_EXPR); |
e89065a1 SL |
1609 | |
1610 | /* Check for boolean identities that don't require recursive examination | |
1611 | of inner1/inner2: | |
1612 | inner1 AND (inner1 AND inner2) => inner1 AND inner2 => var | |
1613 | inner1 AND (inner1 OR inner2) => inner1 | |
1614 | !inner1 AND (inner1 AND inner2) => false | |
1615 | !inner1 AND (inner1 OR inner2) => !inner1 AND inner2 | |
1616 | Likewise for similar cases involving inner2. */ | |
1617 | if (inner1 == true_test_var) | |
1618 | return (is_and ? var : inner1); | |
1619 | else if (inner2 == true_test_var) | |
1620 | return (is_and ? var : inner2); | |
1621 | else if (inner1 == false_test_var) | |
1622 | return (is_and | |
1623 | ? boolean_false_node | |
1624 | : and_var_with_comparison (inner2, false, code2, op2a, op2b)); | |
1625 | else if (inner2 == false_test_var) | |
1626 | return (is_and | |
1627 | ? boolean_false_node | |
1628 | : and_var_with_comparison (inner1, false, code2, op2a, op2b)); | |
1629 | ||
1630 | /* Next, redistribute/reassociate the AND across the inner tests. | |
1631 | Compute the first partial result, (inner1 AND (op2a code op2b)) */ | |
1632 | if (TREE_CODE (inner1) == SSA_NAME | |
1633 | && is_gimple_assign (s = SSA_NAME_DEF_STMT (inner1)) | |
1634 | && TREE_CODE_CLASS (gimple_assign_rhs_code (s)) == tcc_comparison | |
1635 | && (t = maybe_fold_and_comparisons (gimple_assign_rhs_code (s), | |
1636 | gimple_assign_rhs1 (s), | |
1637 | gimple_assign_rhs2 (s), | |
1638 | code2, op2a, op2b))) | |
1639 | { | |
1640 | /* Handle the AND case, where we are reassociating: | |
1641 | (inner1 AND inner2) AND (op2a code2 op2b) | |
1642 | => (t AND inner2) | |
1643 | If the partial result t is a constant, we win. Otherwise | |
1644 | continue on to try reassociating with the other inner test. */ | |
1645 | if (is_and) | |
1646 | { | |
1647 | if (integer_onep (t)) | |
1648 | return inner2; | |
1649 | else if (integer_zerop (t)) | |
1650 | return boolean_false_node; | |
1651 | } | |
1652 | ||
1653 | /* Handle the OR case, where we are redistributing: | |
1654 | (inner1 OR inner2) AND (op2a code2 op2b) | |
1655 | => (t OR (inner2 AND (op2a code2 op2b))) */ | |
8236c8eb JJ |
1656 | else if (integer_onep (t)) |
1657 | return boolean_true_node; | |
1658 | ||
1659 | /* Save partial result for later. */ | |
1660 | partial = t; | |
e89065a1 SL |
1661 | } |
1662 | ||
1663 | /* Compute the second partial result, (inner2 AND (op2a code op2b)) */ | |
1664 | if (TREE_CODE (inner2) == SSA_NAME | |
1665 | && is_gimple_assign (s = SSA_NAME_DEF_STMT (inner2)) | |
1666 | && TREE_CODE_CLASS (gimple_assign_rhs_code (s)) == tcc_comparison | |
1667 | && (t = maybe_fold_and_comparisons (gimple_assign_rhs_code (s), | |
1668 | gimple_assign_rhs1 (s), | |
1669 | gimple_assign_rhs2 (s), | |
1670 | code2, op2a, op2b))) | |
1671 | { | |
1672 | /* Handle the AND case, where we are reassociating: | |
1673 | (inner1 AND inner2) AND (op2a code2 op2b) | |
1674 | => (inner1 AND t) */ | |
1675 | if (is_and) | |
1676 | { | |
1677 | if (integer_onep (t)) | |
1678 | return inner1; | |
1679 | else if (integer_zerop (t)) | |
1680 | return boolean_false_node; | |
8236c8eb JJ |
1681 | /* If both are the same, we can apply the identity |
1682 | (x AND x) == x. */ | |
1683 | else if (partial && same_bool_result_p (t, partial)) | |
1684 | return t; | |
e89065a1 SL |
1685 | } |
1686 | ||
1687 | /* Handle the OR case. where we are redistributing: | |
1688 | (inner1 OR inner2) AND (op2a code2 op2b) | |
1689 | => (t OR (inner1 AND (op2a code2 op2b))) | |
1690 | => (t OR partial) */ | |
1691 | else | |
1692 | { | |
1693 | if (integer_onep (t)) | |
1694 | return boolean_true_node; | |
1695 | else if (partial) | |
1696 | { | |
1697 | /* We already got a simplification for the other | |
1698 | operand to the redistributed OR expression. The | |
1699 | interesting case is when at least one is false. | |
1700 | Or, if both are the same, we can apply the identity | |
1701 | (x OR x) == x. */ | |
1702 | if (integer_zerop (partial)) | |
1703 | return t; | |
1704 | else if (integer_zerop (t)) | |
1705 | return partial; | |
1706 | else if (same_bool_result_p (t, partial)) | |
1707 | return t; | |
1708 | } | |
1709 | } | |
1710 | } | |
1711 | } | |
1712 | return NULL_TREE; | |
1713 | } | |
1714 | ||
1715 | /* Try to simplify the AND of two comparisons defined by | |
1716 | (OP1A CODE1 OP1B) and (OP2A CODE2 OP2B), respectively. | |
1717 | If this can be done without constructing an intermediate value, | |
1718 | return the resulting tree; otherwise NULL_TREE is returned. | |
1719 | This function is deliberately asymmetric as it recurses on SSA_DEFs | |
1720 | in the first comparison but not the second. */ | |
1721 | ||
1722 | static tree | |
1723 | and_comparisons_1 (enum tree_code code1, tree op1a, tree op1b, | |
1724 | enum tree_code code2, tree op2a, tree op2b) | |
1725 | { | |
ae22ac3c | 1726 | tree truth_type = truth_type_for (TREE_TYPE (op1a)); |
31ed6226 | 1727 | |
e89065a1 SL |
1728 | /* First check for ((x CODE1 y) AND (x CODE2 y)). */ |
1729 | if (operand_equal_p (op1a, op2a, 0) | |
1730 | && operand_equal_p (op1b, op2b, 0)) | |
1731 | { | |
eb9820c0 | 1732 | /* Result will be either NULL_TREE, or a combined comparison. */ |
e89065a1 SL |
1733 | tree t = combine_comparisons (UNKNOWN_LOCATION, |
1734 | TRUTH_ANDIF_EXPR, code1, code2, | |
31ed6226 | 1735 | truth_type, op1a, op1b); |
e89065a1 SL |
1736 | if (t) |
1737 | return t; | |
1738 | } | |
1739 | ||
1740 | /* Likewise the swapped case of the above. */ | |
1741 | if (operand_equal_p (op1a, op2b, 0) | |
1742 | && operand_equal_p (op1b, op2a, 0)) | |
1743 | { | |
eb9820c0 | 1744 | /* Result will be either NULL_TREE, or a combined comparison. */ |
e89065a1 SL |
1745 | tree t = combine_comparisons (UNKNOWN_LOCATION, |
1746 | TRUTH_ANDIF_EXPR, code1, | |
1747 | swap_tree_comparison (code2), | |
31ed6226 | 1748 | truth_type, op1a, op1b); |
e89065a1 SL |
1749 | if (t) |
1750 | return t; | |
1751 | } | |
1752 | ||
1753 | /* If both comparisons are of the same value against constants, we might | |
1754 | be able to merge them. */ | |
1755 | if (operand_equal_p (op1a, op2a, 0) | |
1756 | && TREE_CODE (op1b) == INTEGER_CST | |
1757 | && TREE_CODE (op2b) == INTEGER_CST) | |
1758 | { | |
1759 | int cmp = tree_int_cst_compare (op1b, op2b); | |
1760 | ||
1761 | /* If we have (op1a == op1b), we should either be able to | |
1762 | return that or FALSE, depending on whether the constant op1b | |
1763 | also satisfies the other comparison against op2b. */ | |
1764 | if (code1 == EQ_EXPR) | |
1765 | { | |
1766 | bool done = true; | |
1767 | bool val; | |
1768 | switch (code2) | |
1769 | { | |
1770 | case EQ_EXPR: val = (cmp == 0); break; | |
1771 | case NE_EXPR: val = (cmp != 0); break; | |
1772 | case LT_EXPR: val = (cmp < 0); break; | |
1773 | case GT_EXPR: val = (cmp > 0); break; | |
1774 | case LE_EXPR: val = (cmp <= 0); break; | |
1775 | case GE_EXPR: val = (cmp >= 0); break; | |
1776 | default: done = false; | |
1777 | } | |
1778 | if (done) | |
1779 | { | |
1780 | if (val) | |
1781 | return fold_build2 (code1, boolean_type_node, op1a, op1b); | |
1782 | else | |
1783 | return boolean_false_node; | |
1784 | } | |
1785 | } | |
1786 | /* Likewise if the second comparison is an == comparison. */ | |
1787 | else if (code2 == EQ_EXPR) | |
1788 | { | |
1789 | bool done = true; | |
1790 | bool val; | |
1791 | switch (code1) | |
1792 | { | |
1793 | case EQ_EXPR: val = (cmp == 0); break; | |
1794 | case NE_EXPR: val = (cmp != 0); break; | |
1795 | case LT_EXPR: val = (cmp > 0); break; | |
1796 | case GT_EXPR: val = (cmp < 0); break; | |
1797 | case LE_EXPR: val = (cmp >= 0); break; | |
1798 | case GE_EXPR: val = (cmp <= 0); break; | |
1799 | default: done = false; | |
1800 | } | |
1801 | if (done) | |
1802 | { | |
1803 | if (val) | |
1804 | return fold_build2 (code2, boolean_type_node, op2a, op2b); | |
1805 | else | |
1806 | return boolean_false_node; | |
1807 | } | |
1808 | } | |
1809 | ||
1810 | /* Same business with inequality tests. */ | |
1811 | else if (code1 == NE_EXPR) | |
1812 | { | |
1813 | bool val; | |
1814 | switch (code2) | |
1815 | { | |
1816 | case EQ_EXPR: val = (cmp != 0); break; | |
1817 | case NE_EXPR: val = (cmp == 0); break; | |
1818 | case LT_EXPR: val = (cmp >= 0); break; | |
1819 | case GT_EXPR: val = (cmp <= 0); break; | |
1820 | case LE_EXPR: val = (cmp > 0); break; | |
1821 | case GE_EXPR: val = (cmp < 0); break; | |
1822 | default: | |
1823 | val = false; | |
1824 | } | |
1825 | if (val) | |
1826 | return fold_build2 (code2, boolean_type_node, op2a, op2b); | |
1827 | } | |
1828 | else if (code2 == NE_EXPR) | |
1829 | { | |
1830 | bool val; | |
1831 | switch (code1) | |
1832 | { | |
1833 | case EQ_EXPR: val = (cmp == 0); break; | |
1834 | case NE_EXPR: val = (cmp != 0); break; | |
1835 | case LT_EXPR: val = (cmp <= 0); break; | |
1836 | case GT_EXPR: val = (cmp >= 0); break; | |
1837 | case LE_EXPR: val = (cmp < 0); break; | |
1838 | case GE_EXPR: val = (cmp > 0); break; | |
1839 | default: | |
1840 | val = false; | |
1841 | } | |
1842 | if (val) | |
1843 | return fold_build2 (code1, boolean_type_node, op1a, op1b); | |
1844 | } | |
1845 | ||
1846 | /* Chose the more restrictive of two < or <= comparisons. */ | |
1847 | else if ((code1 == LT_EXPR || code1 == LE_EXPR) | |
1848 | && (code2 == LT_EXPR || code2 == LE_EXPR)) | |
1849 | { | |
1850 | if ((cmp < 0) || (cmp == 0 && code1 == LT_EXPR)) | |
1851 | return fold_build2 (code1, boolean_type_node, op1a, op1b); | |
1852 | else | |
1853 | return fold_build2 (code2, boolean_type_node, op2a, op2b); | |
1854 | } | |
1855 | ||
1856 | /* Likewise chose the more restrictive of two > or >= comparisons. */ | |
1857 | else if ((code1 == GT_EXPR || code1 == GE_EXPR) | |
1858 | && (code2 == GT_EXPR || code2 == GE_EXPR)) | |
1859 | { | |
1860 | if ((cmp > 0) || (cmp == 0 && code1 == GT_EXPR)) | |
1861 | return fold_build2 (code1, boolean_type_node, op1a, op1b); | |
1862 | else | |
1863 | return fold_build2 (code2, boolean_type_node, op2a, op2b); | |
1864 | } | |
1865 | ||
1866 | /* Check for singleton ranges. */ | |
1867 | else if (cmp == 0 | |
1868 | && ((code1 == LE_EXPR && code2 == GE_EXPR) | |
1869 | || (code1 == GE_EXPR && code2 == LE_EXPR))) | |
1870 | return fold_build2 (EQ_EXPR, boolean_type_node, op1a, op2b); | |
1871 | ||
1872 | /* Check for disjoint ranges. */ | |
1873 | else if (cmp <= 0 | |
1874 | && (code1 == LT_EXPR || code1 == LE_EXPR) | |
1875 | && (code2 == GT_EXPR || code2 == GE_EXPR)) | |
1876 | return boolean_false_node; | |
1877 | else if (cmp >= 0 | |
1878 | && (code1 == GT_EXPR || code1 == GE_EXPR) | |
1879 | && (code2 == LT_EXPR || code2 == LE_EXPR)) | |
1880 | return boolean_false_node; | |
1881 | } | |
1882 | ||
1883 | /* Perhaps the first comparison is (NAME != 0) or (NAME == 1) where | |
1884 | NAME's definition is a truth value. See if there are any simplifications | |
1885 | that can be done against the NAME's definition. */ | |
1886 | if (TREE_CODE (op1a) == SSA_NAME | |
1887 | && (code1 == NE_EXPR || code1 == EQ_EXPR) | |
1888 | && (integer_zerop (op1b) || integer_onep (op1b))) | |
1889 | { | |
1890 | bool invert = ((code1 == EQ_EXPR && integer_zerop (op1b)) | |
1891 | || (code1 == NE_EXPR && integer_onep (op1b))); | |
1892 | gimple stmt = SSA_NAME_DEF_STMT (op1a); | |
1893 | switch (gimple_code (stmt)) | |
1894 | { | |
1895 | case GIMPLE_ASSIGN: | |
1896 | /* Try to simplify by copy-propagating the definition. */ | |
1897 | return and_var_with_comparison (op1a, invert, code2, op2a, op2b); | |
1898 | ||
1899 | case GIMPLE_PHI: | |
1900 | /* If every argument to the PHI produces the same result when | |
1901 | ANDed with the second comparison, we win. | |
1902 | Do not do this unless the type is bool since we need a bool | |
1903 | result here anyway. */ | |
1904 | if (TREE_CODE (TREE_TYPE (op1a)) == BOOLEAN_TYPE) | |
1905 | { | |
1906 | tree result = NULL_TREE; | |
1907 | unsigned i; | |
1908 | for (i = 0; i < gimple_phi_num_args (stmt); i++) | |
1909 | { | |
1910 | tree arg = gimple_phi_arg_def (stmt, i); | |
1911 | ||
1912 | /* If this PHI has itself as an argument, ignore it. | |
1913 | If all the other args produce the same result, | |
1914 | we're still OK. */ | |
1915 | if (arg == gimple_phi_result (stmt)) | |
1916 | continue; | |
1917 | else if (TREE_CODE (arg) == INTEGER_CST) | |
1918 | { | |
1919 | if (invert ? integer_nonzerop (arg) : integer_zerop (arg)) | |
1920 | { | |
1921 | if (!result) | |
1922 | result = boolean_false_node; | |
1923 | else if (!integer_zerop (result)) | |
1924 | return NULL_TREE; | |
1925 | } | |
1926 | else if (!result) | |
1927 | result = fold_build2 (code2, boolean_type_node, | |
1928 | op2a, op2b); | |
1929 | else if (!same_bool_comparison_p (result, | |
1930 | code2, op2a, op2b)) | |
1931 | return NULL_TREE; | |
1932 | } | |
0e8b84ec JJ |
1933 | else if (TREE_CODE (arg) == SSA_NAME |
1934 | && !SSA_NAME_IS_DEFAULT_DEF (arg)) | |
e89065a1 | 1935 | { |
6c66f733 JJ |
1936 | tree temp; |
1937 | gimple def_stmt = SSA_NAME_DEF_STMT (arg); | |
1938 | /* In simple cases we can look through PHI nodes, | |
1939 | but we have to be careful with loops. | |
1940 | See PR49073. */ | |
1941 | if (! dom_info_available_p (CDI_DOMINATORS) | |
1942 | || gimple_bb (def_stmt) == gimple_bb (stmt) | |
1943 | || dominated_by_p (CDI_DOMINATORS, | |
1944 | gimple_bb (def_stmt), | |
1945 | gimple_bb (stmt))) | |
1946 | return NULL_TREE; | |
1947 | temp = and_var_with_comparison (arg, invert, code2, | |
1948 | op2a, op2b); | |
e89065a1 SL |
1949 | if (!temp) |
1950 | return NULL_TREE; | |
1951 | else if (!result) | |
1952 | result = temp; | |
1953 | else if (!same_bool_result_p (result, temp)) | |
1954 | return NULL_TREE; | |
1955 | } | |
1956 | else | |
1957 | return NULL_TREE; | |
1958 | } | |
1959 | return result; | |
1960 | } | |
1961 | ||
1962 | default: | |
1963 | break; | |
1964 | } | |
1965 | } | |
1966 | return NULL_TREE; | |
1967 | } | |
1968 | ||
1969 | /* Try to simplify the AND of two comparisons, specified by | |
1970 | (OP1A CODE1 OP1B) and (OP2B CODE2 OP2B), respectively. | |
1971 | If this can be simplified to a single expression (without requiring | |
1972 | introducing more SSA variables to hold intermediate values), | |
1973 | return the resulting tree. Otherwise return NULL_TREE. | |
1974 | If the result expression is non-null, it has boolean type. */ | |
1975 | ||
1976 | tree | |
1977 | maybe_fold_and_comparisons (enum tree_code code1, tree op1a, tree op1b, | |
1978 | enum tree_code code2, tree op2a, tree op2b) | |
1979 | { | |
1980 | tree t = and_comparisons_1 (code1, op1a, op1b, code2, op2a, op2b); | |
1981 | if (t) | |
1982 | return t; | |
1983 | else | |
1984 | return and_comparisons_1 (code2, op2a, op2b, code1, op1a, op1b); | |
1985 | } | |
1986 | ||
1987 | /* Helper function for or_comparisons_1: try to simplify the OR of the | |
1988 | ssa variable VAR with the comparison specified by (OP2A CODE2 OP2B). | |
1989 | If INVERT is true, invert the value of VAR before doing the OR. | |
1990 | Return NULL_EXPR if we can't simplify this to a single expression. */ | |
1991 | ||
1992 | static tree | |
1993 | or_var_with_comparison (tree var, bool invert, | |
1994 | enum tree_code code2, tree op2a, tree op2b) | |
1995 | { | |
1996 | tree t; | |
1997 | gimple stmt = SSA_NAME_DEF_STMT (var); | |
1998 | ||
1999 | /* We can only deal with variables whose definitions are assignments. */ | |
2000 | if (!is_gimple_assign (stmt)) | |
2001 | return NULL_TREE; | |
2002 | ||
2003 | /* If we have an inverted comparison, apply DeMorgan's law and rewrite | |
2004 | !var OR (op2a code2 op2b) => !(var AND !(op2a code2 op2b)) | |
2005 | Then we only have to consider the simpler non-inverted cases. */ | |
2006 | if (invert) | |
2007 | t = and_var_with_comparison_1 (stmt, | |
2008 | invert_tree_comparison (code2, false), | |
2009 | op2a, op2b); | |
2010 | else | |
2011 | t = or_var_with_comparison_1 (stmt, code2, op2a, op2b); | |
2012 | return canonicalize_bool (t, invert); | |
2013 | } | |
2014 | ||
2015 | /* Try to simplify the OR of the ssa variable defined by the assignment | |
2016 | STMT with the comparison specified by (OP2A CODE2 OP2B). | |
2017 | Return NULL_EXPR if we can't simplify this to a single expression. */ | |
2018 | ||
2019 | static tree | |
2020 | or_var_with_comparison_1 (gimple stmt, | |
2021 | enum tree_code code2, tree op2a, tree op2b) | |
2022 | { | |
2023 | tree var = gimple_assign_lhs (stmt); | |
2024 | tree true_test_var = NULL_TREE; | |
2025 | tree false_test_var = NULL_TREE; | |
2026 | enum tree_code innercode = gimple_assign_rhs_code (stmt); | |
2027 | ||
2028 | /* Check for identities like (var OR (var != 0)) => true . */ | |
2029 | if (TREE_CODE (op2a) == SSA_NAME | |
2030 | && TREE_CODE (TREE_TYPE (var)) == BOOLEAN_TYPE) | |
2031 | { | |
2032 | if ((code2 == NE_EXPR && integer_zerop (op2b)) | |
2033 | || (code2 == EQ_EXPR && integer_nonzerop (op2b))) | |
2034 | { | |
2035 | true_test_var = op2a; | |
2036 | if (var == true_test_var) | |
2037 | return var; | |
2038 | } | |
2039 | else if ((code2 == EQ_EXPR && integer_zerop (op2b)) | |
2040 | || (code2 == NE_EXPR && integer_nonzerop (op2b))) | |
2041 | { | |
2042 | false_test_var = op2a; | |
2043 | if (var == false_test_var) | |
2044 | return boolean_true_node; | |
2045 | } | |
2046 | } | |
2047 | ||
2048 | /* If the definition is a comparison, recurse on it. */ | |
2049 | if (TREE_CODE_CLASS (innercode) == tcc_comparison) | |
2050 | { | |
2051 | tree t = or_comparisons_1 (innercode, | |
2052 | gimple_assign_rhs1 (stmt), | |
2053 | gimple_assign_rhs2 (stmt), | |
2054 | code2, | |
2055 | op2a, | |
2056 | op2b); | |
2057 | if (t) | |
2058 | return t; | |
2059 | } | |
2060 | ||
2061 | /* If the definition is an AND or OR expression, we may be able to | |
2062 | simplify by reassociating. */ | |
eb9820c0 KT |
2063 | if (TREE_CODE (TREE_TYPE (var)) == BOOLEAN_TYPE |
2064 | && (innercode == BIT_AND_EXPR || innercode == BIT_IOR_EXPR)) | |
e89065a1 SL |
2065 | { |
2066 | tree inner1 = gimple_assign_rhs1 (stmt); | |
2067 | tree inner2 = gimple_assign_rhs2 (stmt); | |
2068 | gimple s; | |
2069 | tree t; | |
2070 | tree partial = NULL_TREE; | |
eb9820c0 | 2071 | bool is_or = (innercode == BIT_IOR_EXPR); |
e89065a1 SL |
2072 | |
2073 | /* Check for boolean identities that don't require recursive examination | |
2074 | of inner1/inner2: | |
2075 | inner1 OR (inner1 OR inner2) => inner1 OR inner2 => var | |
2076 | inner1 OR (inner1 AND inner2) => inner1 | |
2077 | !inner1 OR (inner1 OR inner2) => true | |
2078 | !inner1 OR (inner1 AND inner2) => !inner1 OR inner2 | |
2079 | */ | |
2080 | if (inner1 == true_test_var) | |
2081 | return (is_or ? var : inner1); | |
2082 | else if (inner2 == true_test_var) | |
2083 | return (is_or ? var : inner2); | |
2084 | else if (inner1 == false_test_var) | |
2085 | return (is_or | |
2086 | ? boolean_true_node | |
2087 | : or_var_with_comparison (inner2, false, code2, op2a, op2b)); | |
2088 | else if (inner2 == false_test_var) | |
2089 | return (is_or | |
2090 | ? boolean_true_node | |
2091 | : or_var_with_comparison (inner1, false, code2, op2a, op2b)); | |
2092 | ||
2093 | /* Next, redistribute/reassociate the OR across the inner tests. | |
2094 | Compute the first partial result, (inner1 OR (op2a code op2b)) */ | |
2095 | if (TREE_CODE (inner1) == SSA_NAME | |
2096 | && is_gimple_assign (s = SSA_NAME_DEF_STMT (inner1)) | |
2097 | && TREE_CODE_CLASS (gimple_assign_rhs_code (s)) == tcc_comparison | |
2098 | && (t = maybe_fold_or_comparisons (gimple_assign_rhs_code (s), | |
2099 | gimple_assign_rhs1 (s), | |
2100 | gimple_assign_rhs2 (s), | |
2101 | code2, op2a, op2b))) | |
2102 | { | |
2103 | /* Handle the OR case, where we are reassociating: | |
2104 | (inner1 OR inner2) OR (op2a code2 op2b) | |
2105 | => (t OR inner2) | |
2106 | If the partial result t is a constant, we win. Otherwise | |
2107 | continue on to try reassociating with the other inner test. */ | |
8236c8eb | 2108 | if (is_or) |
e89065a1 SL |
2109 | { |
2110 | if (integer_onep (t)) | |
2111 | return boolean_true_node; | |
2112 | else if (integer_zerop (t)) | |
2113 | return inner2; | |
2114 | } | |
2115 | ||
2116 | /* Handle the AND case, where we are redistributing: | |
2117 | (inner1 AND inner2) OR (op2a code2 op2b) | |
2118 | => (t AND (inner2 OR (op2a code op2b))) */ | |
8236c8eb JJ |
2119 | else if (integer_zerop (t)) |
2120 | return boolean_false_node; | |
2121 | ||
2122 | /* Save partial result for later. */ | |
2123 | partial = t; | |
e89065a1 SL |
2124 | } |
2125 | ||
2126 | /* Compute the second partial result, (inner2 OR (op2a code op2b)) */ | |
2127 | if (TREE_CODE (inner2) == SSA_NAME | |
2128 | && is_gimple_assign (s = SSA_NAME_DEF_STMT (inner2)) | |
2129 | && TREE_CODE_CLASS (gimple_assign_rhs_code (s)) == tcc_comparison | |
2130 | && (t = maybe_fold_or_comparisons (gimple_assign_rhs_code (s), | |
2131 | gimple_assign_rhs1 (s), | |
2132 | gimple_assign_rhs2 (s), | |
2133 | code2, op2a, op2b))) | |
2134 | { | |
2135 | /* Handle the OR case, where we are reassociating: | |
2136 | (inner1 OR inner2) OR (op2a code2 op2b) | |
8236c8eb JJ |
2137 | => (inner1 OR t) |
2138 | => (t OR partial) */ | |
2139 | if (is_or) | |
e89065a1 SL |
2140 | { |
2141 | if (integer_zerop (t)) | |
2142 | return inner1; | |
2143 | else if (integer_onep (t)) | |
2144 | return boolean_true_node; | |
8236c8eb JJ |
2145 | /* If both are the same, we can apply the identity |
2146 | (x OR x) == x. */ | |
2147 | else if (partial && same_bool_result_p (t, partial)) | |
2148 | return t; | |
e89065a1 SL |
2149 | } |
2150 | ||
2151 | /* Handle the AND case, where we are redistributing: | |
2152 | (inner1 AND inner2) OR (op2a code2 op2b) | |
2153 | => (t AND (inner1 OR (op2a code2 op2b))) | |
2154 | => (t AND partial) */ | |
2155 | else | |
2156 | { | |
2157 | if (integer_zerop (t)) | |
2158 | return boolean_false_node; | |
2159 | else if (partial) | |
2160 | { | |
2161 | /* We already got a simplification for the other | |
2162 | operand to the redistributed AND expression. The | |
2163 | interesting case is when at least one is true. | |
2164 | Or, if both are the same, we can apply the identity | |
8236c8eb | 2165 | (x AND x) == x. */ |
e89065a1 SL |
2166 | if (integer_onep (partial)) |
2167 | return t; | |
2168 | else if (integer_onep (t)) | |
2169 | return partial; | |
2170 | else if (same_bool_result_p (t, partial)) | |
8236c8eb | 2171 | return t; |
e89065a1 SL |
2172 | } |
2173 | } | |
2174 | } | |
2175 | } | |
2176 | return NULL_TREE; | |
2177 | } | |
2178 | ||
2179 | /* Try to simplify the OR of two comparisons defined by | |
2180 | (OP1A CODE1 OP1B) and (OP2A CODE2 OP2B), respectively. | |
2181 | If this can be done without constructing an intermediate value, | |
2182 | return the resulting tree; otherwise NULL_TREE is returned. | |
2183 | This function is deliberately asymmetric as it recurses on SSA_DEFs | |
2184 | in the first comparison but not the second. */ | |
2185 | ||
2186 | static tree | |
2187 | or_comparisons_1 (enum tree_code code1, tree op1a, tree op1b, | |
2188 | enum tree_code code2, tree op2a, tree op2b) | |
2189 | { | |
ae22ac3c | 2190 | tree truth_type = truth_type_for (TREE_TYPE (op1a)); |
31ed6226 | 2191 | |
e89065a1 SL |
2192 | /* First check for ((x CODE1 y) OR (x CODE2 y)). */ |
2193 | if (operand_equal_p (op1a, op2a, 0) | |
2194 | && operand_equal_p (op1b, op2b, 0)) | |
2195 | { | |
eb9820c0 | 2196 | /* Result will be either NULL_TREE, or a combined comparison. */ |
e89065a1 SL |
2197 | tree t = combine_comparisons (UNKNOWN_LOCATION, |
2198 | TRUTH_ORIF_EXPR, code1, code2, | |
31ed6226 | 2199 | truth_type, op1a, op1b); |
e89065a1 SL |
2200 | if (t) |
2201 | return t; | |
2202 | } | |
2203 | ||
2204 | /* Likewise the swapped case of the above. */ | |
2205 | if (operand_equal_p (op1a, op2b, 0) | |
2206 | && operand_equal_p (op1b, op2a, 0)) | |
2207 | { | |
eb9820c0 | 2208 | /* Result will be either NULL_TREE, or a combined comparison. */ |
e89065a1 SL |
2209 | tree t = combine_comparisons (UNKNOWN_LOCATION, |
2210 | TRUTH_ORIF_EXPR, code1, | |
2211 | swap_tree_comparison (code2), | |
31ed6226 | 2212 | truth_type, op1a, op1b); |
e89065a1 SL |
2213 | if (t) |
2214 | return t; | |
2215 | } | |
2216 | ||
2217 | /* If both comparisons are of the same value against constants, we might | |
2218 | be able to merge them. */ | |
2219 | if (operand_equal_p (op1a, op2a, 0) | |
2220 | && TREE_CODE (op1b) == INTEGER_CST | |
2221 | && TREE_CODE (op2b) == INTEGER_CST) | |
2222 | { | |
2223 | int cmp = tree_int_cst_compare (op1b, op2b); | |
2224 | ||
2225 | /* If we have (op1a != op1b), we should either be able to | |
2226 | return that or TRUE, depending on whether the constant op1b | |
2227 | also satisfies the other comparison against op2b. */ | |
2228 | if (code1 == NE_EXPR) | |
2229 | { | |
2230 | bool done = true; | |
2231 | bool val; | |
2232 | switch (code2) | |
2233 | { | |
2234 | case EQ_EXPR: val = (cmp == 0); break; | |
2235 | case NE_EXPR: val = (cmp != 0); break; | |
2236 | case LT_EXPR: val = (cmp < 0); break; | |
2237 | case GT_EXPR: val = (cmp > 0); break; | |
2238 | case LE_EXPR: val = (cmp <= 0); break; | |
2239 | case GE_EXPR: val = (cmp >= 0); break; | |
2240 | default: done = false; | |
2241 | } | |
2242 | if (done) | |
2243 | { | |
2244 | if (val) | |
2245 | return boolean_true_node; | |
2246 | else | |
2247 | return fold_build2 (code1, boolean_type_node, op1a, op1b); | |
2248 | } | |
2249 | } | |
2250 | /* Likewise if the second comparison is a != comparison. */ | |
2251 | else if (code2 == NE_EXPR) | |
2252 | { | |
2253 | bool done = true; | |
2254 | bool val; | |
2255 | switch (code1) | |
2256 | { | |
2257 | case EQ_EXPR: val = (cmp == 0); break; | |
2258 | case NE_EXPR: val = (cmp != 0); break; | |
2259 | case LT_EXPR: val = (cmp > 0); break; | |
2260 | case GT_EXPR: val = (cmp < 0); break; | |
2261 | case LE_EXPR: val = (cmp >= 0); break; | |
2262 | case GE_EXPR: val = (cmp <= 0); break; | |
2263 | default: done = false; | |
2264 | } | |
2265 | if (done) | |
2266 | { | |
2267 | if (val) | |
2268 | return boolean_true_node; | |
2269 | else | |
2270 | return fold_build2 (code2, boolean_type_node, op2a, op2b); | |
2271 | } | |
2272 | } | |
2273 | ||
2274 | /* See if an equality test is redundant with the other comparison. */ | |
2275 | else if (code1 == EQ_EXPR) | |
2276 | { | |
2277 | bool val; | |
2278 | switch (code2) | |
2279 | { | |
2280 | case EQ_EXPR: val = (cmp == 0); break; | |
2281 | case NE_EXPR: val = (cmp != 0); break; | |
2282 | case LT_EXPR: val = (cmp < 0); break; | |
2283 | case GT_EXPR: val = (cmp > 0); break; | |
2284 | case LE_EXPR: val = (cmp <= 0); break; | |
2285 | case GE_EXPR: val = (cmp >= 0); break; | |
2286 | default: | |
2287 | val = false; | |
2288 | } | |
2289 | if (val) | |
2290 | return fold_build2 (code2, boolean_type_node, op2a, op2b); | |
2291 | } | |
2292 | else if (code2 == EQ_EXPR) | |
2293 | { | |
2294 | bool val; | |
2295 | switch (code1) | |
2296 | { | |
2297 | case EQ_EXPR: val = (cmp == 0); break; | |
2298 | case NE_EXPR: val = (cmp != 0); break; | |
2299 | case LT_EXPR: val = (cmp > 0); break; | |
2300 | case GT_EXPR: val = (cmp < 0); break; | |
2301 | case LE_EXPR: val = (cmp >= 0); break; | |
2302 | case GE_EXPR: val = (cmp <= 0); break; | |
2303 | default: | |
2304 | val = false; | |
2305 | } | |
2306 | if (val) | |
2307 | return fold_build2 (code1, boolean_type_node, op1a, op1b); | |
2308 | } | |
2309 | ||
2310 | /* Chose the less restrictive of two < or <= comparisons. */ | |
2311 | else if ((code1 == LT_EXPR || code1 == LE_EXPR) | |
2312 | && (code2 == LT_EXPR || code2 == LE_EXPR)) | |
2313 | { | |
2314 | if ((cmp < 0) || (cmp == 0 && code1 == LT_EXPR)) | |
2315 | return fold_build2 (code2, boolean_type_node, op2a, op2b); | |
2316 | else | |
2317 | return fold_build2 (code1, boolean_type_node, op1a, op1b); | |
2318 | } | |
2319 | ||
2320 | /* Likewise chose the less restrictive of two > or >= comparisons. */ | |
2321 | else if ((code1 == GT_EXPR || code1 == GE_EXPR) | |
2322 | && (code2 == GT_EXPR || code2 == GE_EXPR)) | |
2323 | { | |
2324 | if ((cmp > 0) || (cmp == 0 && code1 == GT_EXPR)) | |
2325 | return fold_build2 (code2, boolean_type_node, op2a, op2b); | |
2326 | else | |
2327 | return fold_build2 (code1, boolean_type_node, op1a, op1b); | |
2328 | } | |
2329 | ||
2330 | /* Check for singleton ranges. */ | |
2331 | else if (cmp == 0 | |
2332 | && ((code1 == LT_EXPR && code2 == GT_EXPR) | |
2333 | || (code1 == GT_EXPR && code2 == LT_EXPR))) | |
2334 | return fold_build2 (NE_EXPR, boolean_type_node, op1a, op2b); | |
2335 | ||
2336 | /* Check for less/greater pairs that don't restrict the range at all. */ | |
2337 | else if (cmp >= 0 | |
2338 | && (code1 == LT_EXPR || code1 == LE_EXPR) | |
2339 | && (code2 == GT_EXPR || code2 == GE_EXPR)) | |
2340 | return boolean_true_node; | |
2341 | else if (cmp <= 0 | |
2342 | && (code1 == GT_EXPR || code1 == GE_EXPR) | |
2343 | && (code2 == LT_EXPR || code2 == LE_EXPR)) | |
2344 | return boolean_true_node; | |
2345 | } | |
2346 | ||
2347 | /* Perhaps the first comparison is (NAME != 0) or (NAME == 1) where | |
2348 | NAME's definition is a truth value. See if there are any simplifications | |
2349 | that can be done against the NAME's definition. */ | |
2350 | if (TREE_CODE (op1a) == SSA_NAME | |
2351 | && (code1 == NE_EXPR || code1 == EQ_EXPR) | |
2352 | && (integer_zerop (op1b) || integer_onep (op1b))) | |
2353 | { | |
2354 | bool invert = ((code1 == EQ_EXPR && integer_zerop (op1b)) | |
2355 | || (code1 == NE_EXPR && integer_onep (op1b))); | |
2356 | gimple stmt = SSA_NAME_DEF_STMT (op1a); | |
2357 | switch (gimple_code (stmt)) | |
2358 | { | |
2359 | case GIMPLE_ASSIGN: | |
2360 | /* Try to simplify by copy-propagating the definition. */ | |
2361 | return or_var_with_comparison (op1a, invert, code2, op2a, op2b); | |
2362 | ||
2363 | case GIMPLE_PHI: | |
2364 | /* If every argument to the PHI produces the same result when | |
2365 | ORed with the second comparison, we win. | |
2366 | Do not do this unless the type is bool since we need a bool | |
2367 | result here anyway. */ | |
2368 | if (TREE_CODE (TREE_TYPE (op1a)) == BOOLEAN_TYPE) | |
2369 | { | |
2370 | tree result = NULL_TREE; | |
2371 | unsigned i; | |
2372 | for (i = 0; i < gimple_phi_num_args (stmt); i++) | |
2373 | { | |
2374 | tree arg = gimple_phi_arg_def (stmt, i); | |
2375 | ||
2376 | /* If this PHI has itself as an argument, ignore it. | |
2377 | If all the other args produce the same result, | |
2378 | we're still OK. */ | |
2379 | if (arg == gimple_phi_result (stmt)) | |
2380 | continue; | |
2381 | else if (TREE_CODE (arg) == INTEGER_CST) | |
2382 | { | |
2383 | if (invert ? integer_zerop (arg) : integer_nonzerop (arg)) | |
2384 | { | |
2385 | if (!result) | |
2386 | result = boolean_true_node; | |
2387 | else if (!integer_onep (result)) | |
2388 | return NULL_TREE; | |
2389 | } | |
2390 | else if (!result) | |
2391 | result = fold_build2 (code2, boolean_type_node, | |
2392 | op2a, op2b); | |
2393 | else if (!same_bool_comparison_p (result, | |
2394 | code2, op2a, op2b)) | |
2395 | return NULL_TREE; | |
2396 | } | |
0e8b84ec JJ |
2397 | else if (TREE_CODE (arg) == SSA_NAME |
2398 | && !SSA_NAME_IS_DEFAULT_DEF (arg)) | |
e89065a1 | 2399 | { |
6c66f733 JJ |
2400 | tree temp; |
2401 | gimple def_stmt = SSA_NAME_DEF_STMT (arg); | |
2402 | /* In simple cases we can look through PHI nodes, | |
2403 | but we have to be careful with loops. | |
2404 | See PR49073. */ | |
2405 | if (! dom_info_available_p (CDI_DOMINATORS) | |
2406 | || gimple_bb (def_stmt) == gimple_bb (stmt) | |
2407 | || dominated_by_p (CDI_DOMINATORS, | |
2408 | gimple_bb (def_stmt), | |
2409 | gimple_bb (stmt))) | |
2410 | return NULL_TREE; | |
2411 | temp = or_var_with_comparison (arg, invert, code2, | |
2412 | op2a, op2b); | |
e89065a1 SL |
2413 | if (!temp) |
2414 | return NULL_TREE; | |
2415 | else if (!result) | |
2416 | result = temp; | |
2417 | else if (!same_bool_result_p (result, temp)) | |
2418 | return NULL_TREE; | |
2419 | } | |
2420 | else | |
2421 | return NULL_TREE; | |
2422 | } | |
2423 | return result; | |
2424 | } | |
2425 | ||
2426 | default: | |
2427 | break; | |
2428 | } | |
2429 | } | |
2430 | return NULL_TREE; | |
2431 | } | |
2432 | ||
2433 | /* Try to simplify the OR of two comparisons, specified by | |
2434 | (OP1A CODE1 OP1B) and (OP2B CODE2 OP2B), respectively. | |
2435 | If this can be simplified to a single expression (without requiring | |
2436 | introducing more SSA variables to hold intermediate values), | |
2437 | return the resulting tree. Otherwise return NULL_TREE. | |
2438 | If the result expression is non-null, it has boolean type. */ | |
2439 | ||
2440 | tree | |
2441 | maybe_fold_or_comparisons (enum tree_code code1, tree op1a, tree op1b, | |
2442 | enum tree_code code2, tree op2a, tree op2b) | |
2443 | { | |
2444 | tree t = or_comparisons_1 (code1, op1a, op1b, code2, op2a, op2b); | |
2445 | if (t) | |
2446 | return t; | |
2447 | else | |
2448 | return or_comparisons_1 (code2, op2a, op2b, code1, op1a, op1b); | |
2449 | } | |
cfef45c8 RG |
2450 | |
2451 | ||
2452 | /* Fold STMT to a constant using VALUEIZE to valueize SSA names. | |
2453 | ||
2454 | Either NULL_TREE, a simplified but non-constant or a constant | |
2455 | is returned. | |
2456 | ||
2457 | ??? This should go into a gimple-fold-inline.h file to be eventually | |
2458 | privatized with the single valueize function used in the various TUs | |
2459 | to avoid the indirect function call overhead. */ | |
2460 | ||
2461 | tree | |
2462 | gimple_fold_stmt_to_constant_1 (gimple stmt, tree (*valueize) (tree)) | |
2463 | { | |
2464 | location_t loc = gimple_location (stmt); | |
2465 | switch (gimple_code (stmt)) | |
2466 | { | |
2467 | case GIMPLE_ASSIGN: | |
2468 | { | |
2469 | enum tree_code subcode = gimple_assign_rhs_code (stmt); | |
2470 | ||
2471 | switch (get_gimple_rhs_class (subcode)) | |
2472 | { | |
2473 | case GIMPLE_SINGLE_RHS: | |
2474 | { | |
2475 | tree rhs = gimple_assign_rhs1 (stmt); | |
2476 | enum tree_code_class kind = TREE_CODE_CLASS (subcode); | |
2477 | ||
2478 | if (TREE_CODE (rhs) == SSA_NAME) | |
2479 | { | |
2480 | /* If the RHS is an SSA_NAME, return its known constant value, | |
2481 | if any. */ | |
2482 | return (*valueize) (rhs); | |
2483 | } | |
2484 | /* Handle propagating invariant addresses into address | |
2485 | operations. */ | |
2486 | else if (TREE_CODE (rhs) == ADDR_EXPR | |
2487 | && !is_gimple_min_invariant (rhs)) | |
2488 | { | |
d25c4172 | 2489 | HOST_WIDE_INT offset = 0; |
cfef45c8 RG |
2490 | tree base; |
2491 | base = get_addr_base_and_unit_offset_1 (TREE_OPERAND (rhs, 0), | |
2492 | &offset, | |
2493 | valueize); | |
2494 | if (base | |
2495 | && (CONSTANT_CLASS_P (base) | |
2496 | || decl_address_invariant_p (base))) | |
2497 | return build_invariant_address (TREE_TYPE (rhs), | |
2498 | base, offset); | |
2499 | } | |
2500 | else if (TREE_CODE (rhs) == CONSTRUCTOR | |
2501 | && TREE_CODE (TREE_TYPE (rhs)) == VECTOR_TYPE | |
2502 | && (CONSTRUCTOR_NELTS (rhs) | |
2503 | == TYPE_VECTOR_SUBPARTS (TREE_TYPE (rhs)))) | |
2504 | { | |
2505 | unsigned i; | |
d2a12ae7 | 2506 | tree val, *vec; |
cfef45c8 | 2507 | |
d2a12ae7 RG |
2508 | vec = XALLOCAVEC (tree, |
2509 | TYPE_VECTOR_SUBPARTS (TREE_TYPE (rhs))); | |
cfef45c8 RG |
2510 | FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (rhs), i, val) |
2511 | { | |
2512 | val = (*valueize) (val); | |
2513 | if (TREE_CODE (val) == INTEGER_CST | |
2514 | || TREE_CODE (val) == REAL_CST | |
2515 | || TREE_CODE (val) == FIXED_CST) | |
d2a12ae7 | 2516 | vec[i] = val; |
cfef45c8 RG |
2517 | else |
2518 | return NULL_TREE; | |
2519 | } | |
2520 | ||
d2a12ae7 | 2521 | return build_vector (TREE_TYPE (rhs), vec); |
cfef45c8 RG |
2522 | } |
2523 | ||
2524 | if (kind == tcc_reference) | |
2525 | { | |
2526 | if ((TREE_CODE (rhs) == VIEW_CONVERT_EXPR | |
2527 | || TREE_CODE (rhs) == REALPART_EXPR | |
2528 | || TREE_CODE (rhs) == IMAGPART_EXPR) | |
2529 | && TREE_CODE (TREE_OPERAND (rhs, 0)) == SSA_NAME) | |
2530 | { | |
2531 | tree val = (*valueize) (TREE_OPERAND (rhs, 0)); | |
2532 | return fold_unary_loc (EXPR_LOCATION (rhs), | |
2533 | TREE_CODE (rhs), | |
2534 | TREE_TYPE (rhs), val); | |
2535 | } | |
2536 | else if (TREE_CODE (rhs) == BIT_FIELD_REF | |
2537 | && TREE_CODE (TREE_OPERAND (rhs, 0)) == SSA_NAME) | |
2538 | { | |
2539 | tree val = (*valueize) (TREE_OPERAND (rhs, 0)); | |
2540 | return fold_ternary_loc (EXPR_LOCATION (rhs), | |
2541 | TREE_CODE (rhs), | |
2542 | TREE_TYPE (rhs), val, | |
2543 | TREE_OPERAND (rhs, 1), | |
2544 | TREE_OPERAND (rhs, 2)); | |
2545 | } | |
2546 | else if (TREE_CODE (rhs) == MEM_REF | |
2547 | && TREE_CODE (TREE_OPERAND (rhs, 0)) == SSA_NAME) | |
2548 | { | |
2549 | tree val = (*valueize) (TREE_OPERAND (rhs, 0)); | |
2550 | if (TREE_CODE (val) == ADDR_EXPR | |
2551 | && is_gimple_min_invariant (val)) | |
2552 | { | |
2553 | tree tem = fold_build2 (MEM_REF, TREE_TYPE (rhs), | |
2554 | unshare_expr (val), | |
2555 | TREE_OPERAND (rhs, 1)); | |
2556 | if (tem) | |
2557 | rhs = tem; | |
2558 | } | |
2559 | } | |
2560 | return fold_const_aggregate_ref_1 (rhs, valueize); | |
2561 | } | |
2562 | else if (kind == tcc_declaration) | |
2563 | return get_symbol_constant_value (rhs); | |
2564 | return rhs; | |
2565 | } | |
2566 | ||
2567 | case GIMPLE_UNARY_RHS: | |
2568 | { | |
2569 | /* Handle unary operators that can appear in GIMPLE form. | |
2570 | Note that we know the single operand must be a constant, | |
2571 | so this should almost always return a simplified RHS. */ | |
315f5f1b | 2572 | tree lhs = gimple_assign_lhs (stmt); |
cfef45c8 RG |
2573 | tree op0 = (*valueize) (gimple_assign_rhs1 (stmt)); |
2574 | ||
2575 | /* Conversions are useless for CCP purposes if they are | |
2576 | value-preserving. Thus the restrictions that | |
315f5f1b RG |
2577 | useless_type_conversion_p places for restrict qualification |
2578 | of pointer types should not apply here. | |
2579 | Substitution later will only substitute to allowed places. */ | |
cfef45c8 RG |
2580 | if (CONVERT_EXPR_CODE_P (subcode) |
2581 | && POINTER_TYPE_P (TREE_TYPE (lhs)) | |
315f5f1b | 2582 | && POINTER_TYPE_P (TREE_TYPE (op0)) |
8f420307 EB |
2583 | && TYPE_ADDR_SPACE (TREE_TYPE (lhs)) |
2584 | == TYPE_ADDR_SPACE (TREE_TYPE (op0)) | |
2585 | && TYPE_MODE (TREE_TYPE (lhs)) | |
2586 | == TYPE_MODE (TREE_TYPE (op0))) | |
315f5f1b | 2587 | return op0; |
cfef45c8 RG |
2588 | |
2589 | return | |
2590 | fold_unary_ignore_overflow_loc (loc, subcode, | |
2591 | gimple_expr_type (stmt), op0); | |
2592 | } | |
2593 | ||
2594 | case GIMPLE_BINARY_RHS: | |
2595 | { | |
2596 | /* Handle binary operators that can appear in GIMPLE form. */ | |
2597 | tree op0 = (*valueize) (gimple_assign_rhs1 (stmt)); | |
2598 | tree op1 = (*valueize) (gimple_assign_rhs2 (stmt)); | |
2599 | ||
2600 | /* Translate &x + CST into an invariant form suitable for | |
2601 | further propagation. */ | |
2602 | if (gimple_assign_rhs_code (stmt) == POINTER_PLUS_EXPR | |
2603 | && TREE_CODE (op0) == ADDR_EXPR | |
2604 | && TREE_CODE (op1) == INTEGER_CST) | |
2605 | { | |
2606 | tree off = fold_convert (ptr_type_node, op1); | |
4d59a001 RG |
2607 | return build_fold_addr_expr_loc |
2608 | (loc, | |
2609 | fold_build2 (MEM_REF, | |
cfef45c8 RG |
2610 | TREE_TYPE (TREE_TYPE (op0)), |
2611 | unshare_expr (op0), off)); | |
2612 | } | |
2613 | ||
2614 | return fold_binary_loc (loc, subcode, | |
2615 | gimple_expr_type (stmt), op0, op1); | |
2616 | } | |
2617 | ||
2618 | case GIMPLE_TERNARY_RHS: | |
2619 | { | |
2620 | /* Handle ternary operators that can appear in GIMPLE form. */ | |
2621 | tree op0 = (*valueize) (gimple_assign_rhs1 (stmt)); | |
2622 | tree op1 = (*valueize) (gimple_assign_rhs2 (stmt)); | |
2623 | tree op2 = (*valueize) (gimple_assign_rhs3 (stmt)); | |
2624 | ||
d3878abf RG |
2625 | /* Fold embedded expressions in ternary codes. */ |
2626 | if ((subcode == COND_EXPR | |
2627 | || subcode == VEC_COND_EXPR) | |
2628 | && COMPARISON_CLASS_P (op0)) | |
2629 | { | |
2630 | tree op00 = (*valueize) (TREE_OPERAND (op0, 0)); | |
2631 | tree op01 = (*valueize) (TREE_OPERAND (op0, 1)); | |
2632 | tree tem = fold_binary_loc (loc, TREE_CODE (op0), | |
2633 | TREE_TYPE (op0), op00, op01); | |
2634 | if (tem) | |
2635 | op0 = tem; | |
2636 | } | |
2637 | ||
cfef45c8 RG |
2638 | return fold_ternary_loc (loc, subcode, |
2639 | gimple_expr_type (stmt), op0, op1, op2); | |
2640 | } | |
2641 | ||
2642 | default: | |
2643 | gcc_unreachable (); | |
2644 | } | |
2645 | } | |
2646 | ||
2647 | case GIMPLE_CALL: | |
2648 | { | |
25583c4f RS |
2649 | tree fn; |
2650 | ||
2651 | if (gimple_call_internal_p (stmt)) | |
2652 | /* No folding yet for these functions. */ | |
2653 | return NULL_TREE; | |
2654 | ||
2655 | fn = (*valueize) (gimple_call_fn (stmt)); | |
cfef45c8 RG |
2656 | if (TREE_CODE (fn) == ADDR_EXPR |
2657 | && TREE_CODE (TREE_OPERAND (fn, 0)) == FUNCTION_DECL | |
2658 | && DECL_BUILT_IN (TREE_OPERAND (fn, 0))) | |
2659 | { | |
2660 | tree *args = XALLOCAVEC (tree, gimple_call_num_args (stmt)); | |
2661 | tree call, retval; | |
2662 | unsigned i; | |
2663 | for (i = 0; i < gimple_call_num_args (stmt); ++i) | |
2664 | args[i] = (*valueize) (gimple_call_arg (stmt, i)); | |
2665 | call = build_call_array_loc (loc, | |
2666 | gimple_call_return_type (stmt), | |
2667 | fn, gimple_call_num_args (stmt), args); | |
2668 | retval = fold_call_expr (EXPR_LOCATION (call), call, false); | |
2669 | if (retval) | |
2670 | /* fold_call_expr wraps the result inside a NOP_EXPR. */ | |
2671 | STRIP_NOPS (retval); | |
2672 | return retval; | |
2673 | } | |
2674 | return NULL_TREE; | |
2675 | } | |
2676 | ||
2677 | default: | |
2678 | return NULL_TREE; | |
2679 | } | |
2680 | } | |
2681 | ||
2682 | /* Fold STMT to a constant using VALUEIZE to valueize SSA names. | |
2683 | Returns NULL_TREE if folding to a constant is not possible, otherwise | |
2684 | returns a constant according to is_gimple_min_invariant. */ | |
2685 | ||
2686 | tree | |
2687 | gimple_fold_stmt_to_constant (gimple stmt, tree (*valueize) (tree)) | |
2688 | { | |
2689 | tree res = gimple_fold_stmt_to_constant_1 (stmt, valueize); | |
2690 | if (res && is_gimple_min_invariant (res)) | |
2691 | return res; | |
2692 | return NULL_TREE; | |
2693 | } | |
2694 | ||
2695 | ||
2696 | /* The following set of functions are supposed to fold references using | |
2697 | their constant initializers. */ | |
2698 | ||
2699 | static tree fold_ctor_reference (tree type, tree ctor, | |
2700 | unsigned HOST_WIDE_INT offset, | |
c44c2088 | 2701 | unsigned HOST_WIDE_INT size, tree); |
cfef45c8 RG |
2702 | |
2703 | /* See if we can find constructor defining value of BASE. | |
2704 | When we know the consructor with constant offset (such as | |
2705 | base is array[40] and we do know constructor of array), then | |
2706 | BIT_OFFSET is adjusted accordingly. | |
2707 | ||
2708 | As a special case, return error_mark_node when constructor | |
2709 | is not explicitly available, but it is known to be zero | |
2710 | such as 'static const int a;'. */ | |
2711 | static tree | |
2712 | get_base_constructor (tree base, HOST_WIDE_INT *bit_offset, | |
2713 | tree (*valueize)(tree)) | |
2714 | { | |
2715 | HOST_WIDE_INT bit_offset2, size, max_size; | |
2716 | if (TREE_CODE (base) == MEM_REF) | |
2717 | { | |
2718 | if (!integer_zerop (TREE_OPERAND (base, 1))) | |
2719 | { | |
2720 | if (!host_integerp (TREE_OPERAND (base, 1), 0)) | |
2721 | return NULL_TREE; | |
2722 | *bit_offset += (mem_ref_offset (base).low | |
2723 | * BITS_PER_UNIT); | |
2724 | } | |
2725 | ||
2726 | if (valueize | |
2727 | && TREE_CODE (TREE_OPERAND (base, 0)) == SSA_NAME) | |
2728 | base = valueize (TREE_OPERAND (base, 0)); | |
2729 | if (!base || TREE_CODE (base) != ADDR_EXPR) | |
2730 | return NULL_TREE; | |
2731 | base = TREE_OPERAND (base, 0); | |
2732 | } | |
2733 | ||
2734 | /* Get a CONSTRUCTOR. If BASE is a VAR_DECL, get its | |
2735 | DECL_INITIAL. If BASE is a nested reference into another | |
2736 | ARRAY_REF or COMPONENT_REF, make a recursive call to resolve | |
2737 | the inner reference. */ | |
2738 | switch (TREE_CODE (base)) | |
2739 | { | |
2740 | case VAR_DECL: | |
cfef45c8 | 2741 | case CONST_DECL: |
6a6dac52 JH |
2742 | { |
2743 | tree init = ctor_for_folding (base); | |
2744 | ||
688010ba | 2745 | /* Our semantic is exact opposite of ctor_for_folding; |
6a6dac52 JH |
2746 | NULL means unknown, while error_mark_node is 0. */ |
2747 | if (init == error_mark_node) | |
2748 | return NULL_TREE; | |
2749 | if (!init) | |
2750 | return error_mark_node; | |
2751 | return init; | |
2752 | } | |
cfef45c8 RG |
2753 | |
2754 | case ARRAY_REF: | |
2755 | case COMPONENT_REF: | |
2756 | base = get_ref_base_and_extent (base, &bit_offset2, &size, &max_size); | |
2757 | if (max_size == -1 || size != max_size) | |
2758 | return NULL_TREE; | |
2759 | *bit_offset += bit_offset2; | |
2760 | return get_base_constructor (base, bit_offset, valueize); | |
2761 | ||
2762 | case STRING_CST: | |
2763 | case CONSTRUCTOR: | |
2764 | return base; | |
2765 | ||
2766 | default: | |
2767 | return NULL_TREE; | |
2768 | } | |
2769 | } | |
2770 | ||
2771 | /* CTOR is STRING_CST. Fold reference of type TYPE and size SIZE | |
2772 | to the memory at bit OFFSET. | |
2773 | ||
2774 | We do only simple job of folding byte accesses. */ | |
2775 | ||
2776 | static tree | |
2777 | fold_string_cst_ctor_reference (tree type, tree ctor, | |
2778 | unsigned HOST_WIDE_INT offset, | |
2779 | unsigned HOST_WIDE_INT size) | |
2780 | { | |
2781 | if (INTEGRAL_TYPE_P (type) | |
2782 | && (TYPE_MODE (type) | |
2783 | == TYPE_MODE (TREE_TYPE (TREE_TYPE (ctor)))) | |
2784 | && (GET_MODE_CLASS (TYPE_MODE (TREE_TYPE (TREE_TYPE (ctor)))) | |
2785 | == MODE_INT) | |
2786 | && GET_MODE_SIZE (TYPE_MODE (TREE_TYPE (TREE_TYPE (ctor)))) == 1 | |
2787 | && size == BITS_PER_UNIT | |
2788 | && !(offset % BITS_PER_UNIT)) | |
2789 | { | |
2790 | offset /= BITS_PER_UNIT; | |
2791 | if (offset < (unsigned HOST_WIDE_INT) TREE_STRING_LENGTH (ctor)) | |
2792 | return build_int_cst_type (type, (TREE_STRING_POINTER (ctor) | |
2793 | [offset])); | |
2794 | /* Folding | |
2795 | const char a[20]="hello"; | |
2796 | return a[10]; | |
2797 | ||
2798 | might lead to offset greater than string length. In this case we | |
2799 | know value is either initialized to 0 or out of bounds. Return 0 | |
2800 | in both cases. */ | |
2801 | return build_zero_cst (type); | |
2802 | } | |
2803 | return NULL_TREE; | |
2804 | } | |
2805 | ||
2806 | /* CTOR is CONSTRUCTOR of an array type. Fold reference of type TYPE and size | |
2807 | SIZE to the memory at bit OFFSET. */ | |
2808 | ||
2809 | static tree | |
2810 | fold_array_ctor_reference (tree type, tree ctor, | |
2811 | unsigned HOST_WIDE_INT offset, | |
c44c2088 JH |
2812 | unsigned HOST_WIDE_INT size, |
2813 | tree from_decl) | |
cfef45c8 RG |
2814 | { |
2815 | unsigned HOST_WIDE_INT cnt; | |
2816 | tree cfield, cval; | |
2817 | double_int low_bound, elt_size; | |
2818 | double_int index, max_index; | |
2819 | double_int access_index; | |
b48e22b2 | 2820 | tree domain_type = NULL_TREE, index_type = NULL_TREE; |
cfef45c8 RG |
2821 | HOST_WIDE_INT inner_offset; |
2822 | ||
2823 | /* Compute low bound and elt size. */ | |
eb8f1123 RG |
2824 | if (TREE_CODE (TREE_TYPE (ctor)) == ARRAY_TYPE) |
2825 | domain_type = TYPE_DOMAIN (TREE_TYPE (ctor)); | |
cfef45c8 RG |
2826 | if (domain_type && TYPE_MIN_VALUE (domain_type)) |
2827 | { | |
2828 | /* Static constructors for variably sized objects makes no sense. */ | |
2829 | gcc_assert (TREE_CODE (TYPE_MIN_VALUE (domain_type)) == INTEGER_CST); | |
b48e22b2 | 2830 | index_type = TREE_TYPE (TYPE_MIN_VALUE (domain_type)); |
cfef45c8 RG |
2831 | low_bound = tree_to_double_int (TYPE_MIN_VALUE (domain_type)); |
2832 | } | |
2833 | else | |
2834 | low_bound = double_int_zero; | |
2835 | /* Static constructors for variably sized objects makes no sense. */ | |
c3284718 | 2836 | gcc_assert (TREE_CODE (TYPE_SIZE_UNIT (TREE_TYPE (TREE_TYPE (ctor)))) |
cfef45c8 RG |
2837 | == INTEGER_CST); |
2838 | elt_size = | |
2839 | tree_to_double_int (TYPE_SIZE_UNIT (TREE_TYPE (TREE_TYPE (ctor)))); | |
2840 | ||
2841 | ||
2842 | /* We can handle only constantly sized accesses that are known to not | |
2843 | be larger than size of array element. */ | |
2844 | if (!TYPE_SIZE_UNIT (type) | |
2845 | || TREE_CODE (TYPE_SIZE_UNIT (type)) != INTEGER_CST | |
27bcd47c | 2846 | || elt_size.slt (tree_to_double_int (TYPE_SIZE_UNIT (type)))) |
cfef45c8 RG |
2847 | return NULL_TREE; |
2848 | ||
2849 | /* Compute the array index we look for. */ | |
27bcd47c LC |
2850 | access_index = double_int::from_uhwi (offset / BITS_PER_UNIT) |
2851 | .udiv (elt_size, TRUNC_DIV_EXPR); | |
2852 | access_index += low_bound; | |
b48e22b2 | 2853 | if (index_type) |
27bcd47c LC |
2854 | access_index = access_index.ext (TYPE_PRECISION (index_type), |
2855 | TYPE_UNSIGNED (index_type)); | |
cfef45c8 RG |
2856 | |
2857 | /* And offset within the access. */ | |
27bcd47c | 2858 | inner_offset = offset % (elt_size.to_uhwi () * BITS_PER_UNIT); |
cfef45c8 RG |
2859 | |
2860 | /* See if the array field is large enough to span whole access. We do not | |
2861 | care to fold accesses spanning multiple array indexes. */ | |
27bcd47c | 2862 | if (inner_offset + size > elt_size.to_uhwi () * BITS_PER_UNIT) |
cfef45c8 RG |
2863 | return NULL_TREE; |
2864 | ||
27bcd47c | 2865 | index = low_bound - double_int_one; |
b48e22b2 | 2866 | if (index_type) |
27bcd47c | 2867 | index = index.ext (TYPE_PRECISION (index_type), TYPE_UNSIGNED (index_type)); |
b48e22b2 | 2868 | |
cfef45c8 RG |
2869 | FOR_EACH_CONSTRUCTOR_ELT (CONSTRUCTOR_ELTS (ctor), cnt, cfield, cval) |
2870 | { | |
2871 | /* Array constructor might explicitely set index, or specify range | |
2872 | or leave index NULL meaning that it is next index after previous | |
2873 | one. */ | |
2874 | if (cfield) | |
2875 | { | |
2876 | if (TREE_CODE (cfield) == INTEGER_CST) | |
2877 | max_index = index = tree_to_double_int (cfield); | |
2878 | else | |
2879 | { | |
2880 | gcc_assert (TREE_CODE (cfield) == RANGE_EXPR); | |
2881 | index = tree_to_double_int (TREE_OPERAND (cfield, 0)); | |
2882 | max_index = tree_to_double_int (TREE_OPERAND (cfield, 1)); | |
2883 | } | |
2884 | } | |
2885 | else | |
b48e22b2 | 2886 | { |
27bcd47c | 2887 | index += double_int_one; |
b48e22b2 | 2888 | if (index_type) |
27bcd47c LC |
2889 | index = index.ext (TYPE_PRECISION (index_type), |
2890 | TYPE_UNSIGNED (index_type)); | |
b48e22b2 EB |
2891 | max_index = index; |
2892 | } | |
cfef45c8 RG |
2893 | |
2894 | /* Do we have match? */ | |
27bcd47c LC |
2895 | if (access_index.cmp (index, 1) >= 0 |
2896 | && access_index.cmp (max_index, 1) <= 0) | |
c44c2088 JH |
2897 | return fold_ctor_reference (type, cval, inner_offset, size, |
2898 | from_decl); | |
cfef45c8 RG |
2899 | } |
2900 | /* When memory is not explicitely mentioned in constructor, | |
2901 | it is 0 (or out of range). */ | |
2902 | return build_zero_cst (type); | |
2903 | } | |
2904 | ||
2905 | /* CTOR is CONSTRUCTOR of an aggregate or vector. | |
2906 | Fold reference of type TYPE and size SIZE to the memory at bit OFFSET. */ | |
2907 | ||
2908 | static tree | |
2909 | fold_nonarray_ctor_reference (tree type, tree ctor, | |
2910 | unsigned HOST_WIDE_INT offset, | |
c44c2088 JH |
2911 | unsigned HOST_WIDE_INT size, |
2912 | tree from_decl) | |
cfef45c8 RG |
2913 | { |
2914 | unsigned HOST_WIDE_INT cnt; | |
2915 | tree cfield, cval; | |
2916 | ||
2917 | FOR_EACH_CONSTRUCTOR_ELT (CONSTRUCTOR_ELTS (ctor), cnt, cfield, | |
2918 | cval) | |
2919 | { | |
2920 | tree byte_offset = DECL_FIELD_OFFSET (cfield); | |
2921 | tree field_offset = DECL_FIELD_BIT_OFFSET (cfield); | |
2922 | tree field_size = DECL_SIZE (cfield); | |
2923 | double_int bitoffset; | |
2924 | double_int byte_offset_cst = tree_to_double_int (byte_offset); | |
27bcd47c | 2925 | double_int bits_per_unit_cst = double_int::from_uhwi (BITS_PER_UNIT); |
b8b2b009 | 2926 | double_int bitoffset_end, access_end; |
cfef45c8 RG |
2927 | |
2928 | /* Variable sized objects in static constructors makes no sense, | |
2929 | but field_size can be NULL for flexible array members. */ | |
2930 | gcc_assert (TREE_CODE (field_offset) == INTEGER_CST | |
2931 | && TREE_CODE (byte_offset) == INTEGER_CST | |
2932 | && (field_size != NULL_TREE | |
2933 | ? TREE_CODE (field_size) == INTEGER_CST | |
2934 | : TREE_CODE (TREE_TYPE (cfield)) == ARRAY_TYPE)); | |
2935 | ||
2936 | /* Compute bit offset of the field. */ | |
27bcd47c LC |
2937 | bitoffset = tree_to_double_int (field_offset) |
2938 | + byte_offset_cst * bits_per_unit_cst; | |
cfef45c8 RG |
2939 | /* Compute bit offset where the field ends. */ |
2940 | if (field_size != NULL_TREE) | |
27bcd47c | 2941 | bitoffset_end = bitoffset + tree_to_double_int (field_size); |
cfef45c8 RG |
2942 | else |
2943 | bitoffset_end = double_int_zero; | |
2944 | ||
27bcd47c LC |
2945 | access_end = double_int::from_uhwi (offset) |
2946 | + double_int::from_uhwi (size); | |
b8b2b009 JJ |
2947 | |
2948 | /* Is there any overlap between [OFFSET, OFFSET+SIZE) and | |
2949 | [BITOFFSET, BITOFFSET_END)? */ | |
27bcd47c | 2950 | if (access_end.cmp (bitoffset, 0) > 0 |
cfef45c8 | 2951 | && (field_size == NULL_TREE |
27bcd47c | 2952 | || double_int::from_uhwi (offset).slt (bitoffset_end))) |
cfef45c8 | 2953 | { |
27bcd47c | 2954 | double_int inner_offset = double_int::from_uhwi (offset) - bitoffset; |
cfef45c8 RG |
2955 | /* We do have overlap. Now see if field is large enough to |
2956 | cover the access. Give up for accesses spanning multiple | |
2957 | fields. */ | |
27bcd47c | 2958 | if (access_end.cmp (bitoffset_end, 0) > 0) |
cfef45c8 | 2959 | return NULL_TREE; |
27bcd47c | 2960 | if (double_int::from_uhwi (offset).slt (bitoffset)) |
b8b2b009 | 2961 | return NULL_TREE; |
cfef45c8 | 2962 | return fold_ctor_reference (type, cval, |
27bcd47c | 2963 | inner_offset.to_uhwi (), size, |
c44c2088 | 2964 | from_decl); |
cfef45c8 RG |
2965 | } |
2966 | } | |
2967 | /* When memory is not explicitely mentioned in constructor, it is 0. */ | |
2968 | return build_zero_cst (type); | |
2969 | } | |
2970 | ||
2971 | /* CTOR is value initializing memory, fold reference of type TYPE and size SIZE | |
2972 | to the memory at bit OFFSET. */ | |
2973 | ||
2974 | static tree | |
2975 | fold_ctor_reference (tree type, tree ctor, unsigned HOST_WIDE_INT offset, | |
c44c2088 | 2976 | unsigned HOST_WIDE_INT size, tree from_decl) |
cfef45c8 RG |
2977 | { |
2978 | tree ret; | |
2979 | ||
2980 | /* We found the field with exact match. */ | |
2981 | if (useless_type_conversion_p (type, TREE_TYPE (ctor)) | |
2982 | && !offset) | |
9d60be38 | 2983 | return canonicalize_constructor_val (unshare_expr (ctor), from_decl); |
cfef45c8 RG |
2984 | |
2985 | /* We are at the end of walk, see if we can view convert the | |
2986 | result. */ | |
2987 | if (!AGGREGATE_TYPE_P (TREE_TYPE (ctor)) && !offset | |
2988 | /* VIEW_CONVERT_EXPR is defined only for matching sizes. */ | |
2989 | && operand_equal_p (TYPE_SIZE (type), | |
2990 | TYPE_SIZE (TREE_TYPE (ctor)), 0)) | |
2991 | { | |
9d60be38 | 2992 | ret = canonicalize_constructor_val (unshare_expr (ctor), from_decl); |
cfef45c8 RG |
2993 | ret = fold_unary (VIEW_CONVERT_EXPR, type, ret); |
2994 | if (ret) | |
2995 | STRIP_NOPS (ret); | |
2996 | return ret; | |
2997 | } | |
2998 | if (TREE_CODE (ctor) == STRING_CST) | |
2999 | return fold_string_cst_ctor_reference (type, ctor, offset, size); | |
3000 | if (TREE_CODE (ctor) == CONSTRUCTOR) | |
3001 | { | |
3002 | ||
eb8f1123 RG |
3003 | if (TREE_CODE (TREE_TYPE (ctor)) == ARRAY_TYPE |
3004 | || TREE_CODE (TREE_TYPE (ctor)) == VECTOR_TYPE) | |
c44c2088 JH |
3005 | return fold_array_ctor_reference (type, ctor, offset, size, |
3006 | from_decl); | |
cfef45c8 | 3007 | else |
c44c2088 JH |
3008 | return fold_nonarray_ctor_reference (type, ctor, offset, size, |
3009 | from_decl); | |
cfef45c8 RG |
3010 | } |
3011 | ||
3012 | return NULL_TREE; | |
3013 | } | |
3014 | ||
3015 | /* Return the tree representing the element referenced by T if T is an | |
3016 | ARRAY_REF or COMPONENT_REF into constant aggregates valuezing SSA | |
3017 | names using VALUEIZE. Return NULL_TREE otherwise. */ | |
3018 | ||
3019 | tree | |
3020 | fold_const_aggregate_ref_1 (tree t, tree (*valueize) (tree)) | |
3021 | { | |
3022 | tree ctor, idx, base; | |
3023 | HOST_WIDE_INT offset, size, max_size; | |
3024 | tree tem; | |
3025 | ||
f8a7df45 RG |
3026 | if (TREE_THIS_VOLATILE (t)) |
3027 | return NULL_TREE; | |
3028 | ||
cfef45c8 RG |
3029 | if (TREE_CODE_CLASS (TREE_CODE (t)) == tcc_declaration) |
3030 | return get_symbol_constant_value (t); | |
3031 | ||
3032 | tem = fold_read_from_constant_string (t); | |
3033 | if (tem) | |
3034 | return tem; | |
3035 | ||
3036 | switch (TREE_CODE (t)) | |
3037 | { | |
3038 | case ARRAY_REF: | |
3039 | case ARRAY_RANGE_REF: | |
3040 | /* Constant indexes are handled well by get_base_constructor. | |
3041 | Only special case variable offsets. | |
3042 | FIXME: This code can't handle nested references with variable indexes | |
3043 | (they will be handled only by iteration of ccp). Perhaps we can bring | |
3044 | get_ref_base_and_extent here and make it use a valueize callback. */ | |
3045 | if (TREE_CODE (TREE_OPERAND (t, 1)) == SSA_NAME | |
3046 | && valueize | |
3047 | && (idx = (*valueize) (TREE_OPERAND (t, 1))) | |
b48e22b2 | 3048 | && TREE_CODE (idx) == INTEGER_CST) |
cfef45c8 RG |
3049 | { |
3050 | tree low_bound, unit_size; | |
b48e22b2 | 3051 | double_int doffset; |
cfef45c8 RG |
3052 | |
3053 | /* If the resulting bit-offset is constant, track it. */ | |
3054 | if ((low_bound = array_ref_low_bound (t), | |
b48e22b2 | 3055 | TREE_CODE (low_bound) == INTEGER_CST) |
cfef45c8 | 3056 | && (unit_size = array_ref_element_size (t), |
b48e22b2 | 3057 | host_integerp (unit_size, 1)) |
27bcd47c LC |
3058 | && (doffset = (TREE_INT_CST (idx) - TREE_INT_CST (low_bound)) |
3059 | .sext (TYPE_PRECISION (TREE_TYPE (idx))), | |
3060 | doffset.fits_shwi ())) | |
cfef45c8 | 3061 | { |
27bcd47c | 3062 | offset = doffset.to_shwi (); |
cfef45c8 RG |
3063 | offset *= TREE_INT_CST_LOW (unit_size); |
3064 | offset *= BITS_PER_UNIT; | |
3065 | ||
3066 | base = TREE_OPERAND (t, 0); | |
3067 | ctor = get_base_constructor (base, &offset, valueize); | |
3068 | /* Empty constructor. Always fold to 0. */ | |
3069 | if (ctor == error_mark_node) | |
3070 | return build_zero_cst (TREE_TYPE (t)); | |
3071 | /* Out of bound array access. Value is undefined, | |
3072 | but don't fold. */ | |
3073 | if (offset < 0) | |
3074 | return NULL_TREE; | |
3075 | /* We can not determine ctor. */ | |
3076 | if (!ctor) | |
3077 | return NULL_TREE; | |
3078 | return fold_ctor_reference (TREE_TYPE (t), ctor, offset, | |
3079 | TREE_INT_CST_LOW (unit_size) | |
c44c2088 JH |
3080 | * BITS_PER_UNIT, |
3081 | base); | |
cfef45c8 RG |
3082 | } |
3083 | } | |
3084 | /* Fallthru. */ | |
3085 | ||
3086 | case COMPONENT_REF: | |
3087 | case BIT_FIELD_REF: | |
3088 | case TARGET_MEM_REF: | |
3089 | case MEM_REF: | |
3090 | base = get_ref_base_and_extent (t, &offset, &size, &max_size); | |
3091 | ctor = get_base_constructor (base, &offset, valueize); | |
3092 | ||
3093 | /* Empty constructor. Always fold to 0. */ | |
3094 | if (ctor == error_mark_node) | |
3095 | return build_zero_cst (TREE_TYPE (t)); | |
3096 | /* We do not know precise address. */ | |
3097 | if (max_size == -1 || max_size != size) | |
3098 | return NULL_TREE; | |
3099 | /* We can not determine ctor. */ | |
3100 | if (!ctor) | |
3101 | return NULL_TREE; | |
3102 | ||
3103 | /* Out of bound array access. Value is undefined, but don't fold. */ | |
3104 | if (offset < 0) | |
3105 | return NULL_TREE; | |
3106 | ||
c44c2088 JH |
3107 | return fold_ctor_reference (TREE_TYPE (t), ctor, offset, size, |
3108 | base); | |
cfef45c8 RG |
3109 | |
3110 | case REALPART_EXPR: | |
3111 | case IMAGPART_EXPR: | |
3112 | { | |
3113 | tree c = fold_const_aggregate_ref_1 (TREE_OPERAND (t, 0), valueize); | |
3114 | if (c && TREE_CODE (c) == COMPLEX_CST) | |
3115 | return fold_build1_loc (EXPR_LOCATION (t), | |
3116 | TREE_CODE (t), TREE_TYPE (t), c); | |
3117 | break; | |
3118 | } | |
3119 | ||
3120 | default: | |
3121 | break; | |
3122 | } | |
3123 | ||
3124 | return NULL_TREE; | |
3125 | } | |
3126 | ||
3127 | tree | |
3128 | fold_const_aggregate_ref (tree t) | |
3129 | { | |
3130 | return fold_const_aggregate_ref_1 (t, NULL); | |
3131 | } | |
06bc3ec7 | 3132 | |
81fa35bd MJ |
3133 | /* Return a declaration of a function which an OBJ_TYPE_REF references. TOKEN |
3134 | is integer form of OBJ_TYPE_REF_TOKEN of the reference expression. | |
3135 | KNOWN_BINFO carries the binfo describing the true type of | |
3136 | OBJ_TYPE_REF_OBJECT(REF). */ | |
3137 | ||
3138 | tree | |
3139 | gimple_get_virt_method_for_binfo (HOST_WIDE_INT token, tree known_binfo) | |
3140 | { | |
3141 | unsigned HOST_WIDE_INT offset, size; | |
2aa3da06 | 3142 | tree v, fn, vtable, init; |
81fa35bd | 3143 | |
c44c2088 | 3144 | vtable = v = BINFO_VTABLE (known_binfo); |
81fa35bd MJ |
3145 | /* If there is no virtual methods table, leave the OBJ_TYPE_REF alone. */ |
3146 | if (!v) | |
3147 | return NULL_TREE; | |
3148 | ||
3149 | if (TREE_CODE (v) == POINTER_PLUS_EXPR) | |
3150 | { | |
3151 | offset = tree_low_cst (TREE_OPERAND (v, 1), 1) * BITS_PER_UNIT; | |
3152 | v = TREE_OPERAND (v, 0); | |
3153 | } | |
3154 | else | |
3155 | offset = 0; | |
3156 | ||
3157 | if (TREE_CODE (v) != ADDR_EXPR) | |
3158 | return NULL_TREE; | |
3159 | v = TREE_OPERAND (v, 0); | |
3160 | ||
3161 | if (TREE_CODE (v) != VAR_DECL | |
2aa3da06 | 3162 | || !DECL_VIRTUAL_P (v)) |
81fa35bd | 3163 | return NULL_TREE; |
2aa3da06 JH |
3164 | init = ctor_for_folding (v); |
3165 | ||
3166 | /* The virtual tables should always be born with constructors. | |
3167 | and we always should assume that they are avaialble for | |
3168 | folding. At the moment we do not stream them in all cases, | |
3169 | but it should never happen that ctor seem unreachable. */ | |
3170 | gcc_assert (init); | |
3171 | if (init == error_mark_node) | |
3172 | { | |
3173 | gcc_assert (in_lto_p); | |
3174 | return NULL_TREE; | |
3175 | } | |
81fa35bd MJ |
3176 | gcc_checking_assert (TREE_CODE (TREE_TYPE (v)) == ARRAY_TYPE); |
3177 | size = tree_low_cst (TYPE_SIZE (TREE_TYPE (TREE_TYPE (v))), 1); | |
3178 | offset += token * size; | |
2aa3da06 | 3179 | fn = fold_ctor_reference (TREE_TYPE (TREE_TYPE (v)), init, |
668b6894 | 3180 | offset, size, v); |
8e8483e6 | 3181 | if (!fn || integer_zerop (fn)) |
81fa35bd MJ |
3182 | return NULL_TREE; |
3183 | gcc_assert (TREE_CODE (fn) == ADDR_EXPR | |
3184 | || TREE_CODE (fn) == FDESC_EXPR); | |
3185 | fn = TREE_OPERAND (fn, 0); | |
3186 | gcc_assert (TREE_CODE (fn) == FUNCTION_DECL); | |
3187 | ||
3188 | /* When cgraph node is missing and function is not public, we cannot | |
3189 | devirtualize. This can happen in WHOPR when the actual method | |
3190 | ends up in other partition, because we found devirtualization | |
3191 | possibility too late. */ | |
c44c2088 | 3192 | if (!can_refer_decl_in_current_unit_p (fn, vtable)) |
81fa35bd MJ |
3193 | return NULL_TREE; |
3194 | ||
7501ca28 RG |
3195 | /* Make sure we create a cgraph node for functions we'll reference. |
3196 | They can be non-existent if the reference comes from an entry | |
3197 | of an external vtable for example. */ | |
3198 | cgraph_get_create_node (fn); | |
3199 | ||
81fa35bd MJ |
3200 | return fn; |
3201 | } | |
3202 | ||
06bc3ec7 BS |
3203 | /* Return true iff VAL is a gimple expression that is known to be |
3204 | non-negative. Restricted to floating-point inputs. */ | |
3205 | ||
3206 | bool | |
3207 | gimple_val_nonnegative_real_p (tree val) | |
3208 | { | |
3209 | gimple def_stmt; | |
3210 | ||
3211 | gcc_assert (val && SCALAR_FLOAT_TYPE_P (TREE_TYPE (val))); | |
3212 | ||
3213 | /* Use existing logic for non-gimple trees. */ | |
3214 | if (tree_expr_nonnegative_p (val)) | |
3215 | return true; | |
3216 | ||
3217 | if (TREE_CODE (val) != SSA_NAME) | |
3218 | return false; | |
3219 | ||
3220 | /* Currently we look only at the immediately defining statement | |
3221 | to make this determination, since recursion on defining | |
3222 | statements of operands can lead to quadratic behavior in the | |
3223 | worst case. This is expected to catch almost all occurrences | |
3224 | in practice. It would be possible to implement limited-depth | |
3225 | recursion if important cases are lost. Alternatively, passes | |
3226 | that need this information (such as the pow/powi lowering code | |
3227 | in the cse_sincos pass) could be revised to provide it through | |
3228 | dataflow propagation. */ | |
3229 | ||
3230 | def_stmt = SSA_NAME_DEF_STMT (val); | |
3231 | ||
3232 | if (is_gimple_assign (def_stmt)) | |
3233 | { | |
3234 | tree op0, op1; | |
3235 | ||
3236 | /* See fold-const.c:tree_expr_nonnegative_p for additional | |
3237 | cases that could be handled with recursion. */ | |
3238 | ||
3239 | switch (gimple_assign_rhs_code (def_stmt)) | |
3240 | { | |
3241 | case ABS_EXPR: | |
3242 | /* Always true for floating-point operands. */ | |
3243 | return true; | |
3244 | ||
3245 | case MULT_EXPR: | |
3246 | /* True if the two operands are identical (since we are | |
3247 | restricted to floating-point inputs). */ | |
3248 | op0 = gimple_assign_rhs1 (def_stmt); | |
3249 | op1 = gimple_assign_rhs2 (def_stmt); | |
3250 | ||
3251 | if (op0 == op1 | |
3252 | || operand_equal_p (op0, op1, 0)) | |
3253 | return true; | |
3254 | ||
3255 | default: | |
3256 | return false; | |
3257 | } | |
3258 | } | |
3259 | else if (is_gimple_call (def_stmt)) | |
3260 | { | |
3261 | tree fndecl = gimple_call_fndecl (def_stmt); | |
3262 | if (fndecl | |
3263 | && DECL_BUILT_IN_CLASS (fndecl) == BUILT_IN_NORMAL) | |
3264 | { | |
3265 | tree arg1; | |
3266 | ||
3267 | switch (DECL_FUNCTION_CODE (fndecl)) | |
3268 | { | |
3269 | CASE_FLT_FN (BUILT_IN_ACOS): | |
3270 | CASE_FLT_FN (BUILT_IN_ACOSH): | |
3271 | CASE_FLT_FN (BUILT_IN_CABS): | |
3272 | CASE_FLT_FN (BUILT_IN_COSH): | |
3273 | CASE_FLT_FN (BUILT_IN_ERFC): | |
3274 | CASE_FLT_FN (BUILT_IN_EXP): | |
3275 | CASE_FLT_FN (BUILT_IN_EXP10): | |
3276 | CASE_FLT_FN (BUILT_IN_EXP2): | |
3277 | CASE_FLT_FN (BUILT_IN_FABS): | |
3278 | CASE_FLT_FN (BUILT_IN_FDIM): | |
3279 | CASE_FLT_FN (BUILT_IN_HYPOT): | |
3280 | CASE_FLT_FN (BUILT_IN_POW10): | |
3281 | return true; | |
3282 | ||
3283 | CASE_FLT_FN (BUILT_IN_SQRT): | |
3284 | /* sqrt(-0.0) is -0.0, and sqrt is not defined over other | |
3285 | nonnegative inputs. */ | |
3286 | if (!HONOR_SIGNED_ZEROS (TYPE_MODE (TREE_TYPE (val)))) | |
3287 | return true; | |
3288 | ||
3289 | break; | |
3290 | ||
3291 | CASE_FLT_FN (BUILT_IN_POWI): | |
3292 | /* True if the second argument is an even integer. */ | |
3293 | arg1 = gimple_call_arg (def_stmt, 1); | |
3294 | ||
3295 | if (TREE_CODE (arg1) == INTEGER_CST | |
3296 | && (TREE_INT_CST_LOW (arg1) & 1) == 0) | |
3297 | return true; | |
3298 | ||
3299 | break; | |
3300 | ||
3301 | CASE_FLT_FN (BUILT_IN_POW): | |
3302 | /* True if the second argument is an even integer-valued | |
3303 | real. */ | |
3304 | arg1 = gimple_call_arg (def_stmt, 1); | |
3305 | ||
3306 | if (TREE_CODE (arg1) == REAL_CST) | |
3307 | { | |
3308 | REAL_VALUE_TYPE c; | |
3309 | HOST_WIDE_INT n; | |
3310 | ||
3311 | c = TREE_REAL_CST (arg1); | |
3312 | n = real_to_integer (&c); | |
3313 | ||
3314 | if ((n & 1) == 0) | |
3315 | { | |
3316 | REAL_VALUE_TYPE cint; | |
3317 | real_from_integer (&cint, VOIDmode, n, n < 0 ? -1 : 0, 0); | |
3318 | if (real_identical (&c, &cint)) | |
3319 | return true; | |
3320 | } | |
3321 | } | |
3322 | ||
3323 | break; | |
3324 | ||
3325 | default: | |
3326 | return false; | |
3327 | } | |
3328 | } | |
3329 | } | |
3330 | ||
3331 | return false; | |
3332 | } | |
b184c8f1 AM |
3333 | |
3334 | /* Given a pointer value OP0, return a simplified version of an | |
3335 | indirection through OP0, or NULL_TREE if no simplification is | |
3336 | possible. Note that the resulting type may be different from | |
3337 | the type pointed to in the sense that it is still compatible | |
3338 | from the langhooks point of view. */ | |
3339 | ||
3340 | tree | |
3341 | gimple_fold_indirect_ref (tree t) | |
3342 | { | |
3343 | tree ptype = TREE_TYPE (t), type = TREE_TYPE (ptype); | |
3344 | tree sub = t; | |
3345 | tree subtype; | |
3346 | ||
3347 | STRIP_NOPS (sub); | |
3348 | subtype = TREE_TYPE (sub); | |
3349 | if (!POINTER_TYPE_P (subtype)) | |
3350 | return NULL_TREE; | |
3351 | ||
3352 | if (TREE_CODE (sub) == ADDR_EXPR) | |
3353 | { | |
3354 | tree op = TREE_OPERAND (sub, 0); | |
3355 | tree optype = TREE_TYPE (op); | |
3356 | /* *&p => p */ | |
3357 | if (useless_type_conversion_p (type, optype)) | |
3358 | return op; | |
3359 | ||
3360 | /* *(foo *)&fooarray => fooarray[0] */ | |
3361 | if (TREE_CODE (optype) == ARRAY_TYPE | |
3362 | && TREE_CODE (TYPE_SIZE (TREE_TYPE (optype))) == INTEGER_CST | |
3363 | && useless_type_conversion_p (type, TREE_TYPE (optype))) | |
3364 | { | |
3365 | tree type_domain = TYPE_DOMAIN (optype); | |
3366 | tree min_val = size_zero_node; | |
3367 | if (type_domain && TYPE_MIN_VALUE (type_domain)) | |
3368 | min_val = TYPE_MIN_VALUE (type_domain); | |
3369 | if (TREE_CODE (min_val) == INTEGER_CST) | |
3370 | return build4 (ARRAY_REF, type, op, min_val, NULL_TREE, NULL_TREE); | |
3371 | } | |
3372 | /* *(foo *)&complexfoo => __real__ complexfoo */ | |
3373 | else if (TREE_CODE (optype) == COMPLEX_TYPE | |
3374 | && useless_type_conversion_p (type, TREE_TYPE (optype))) | |
3375 | return fold_build1 (REALPART_EXPR, type, op); | |
3376 | /* *(foo *)&vectorfoo => BIT_FIELD_REF<vectorfoo,...> */ | |
3377 | else if (TREE_CODE (optype) == VECTOR_TYPE | |
3378 | && useless_type_conversion_p (type, TREE_TYPE (optype))) | |
3379 | { | |
3380 | tree part_width = TYPE_SIZE (type); | |
3381 | tree index = bitsize_int (0); | |
3382 | return fold_build3 (BIT_FIELD_REF, type, op, part_width, index); | |
3383 | } | |
3384 | } | |
3385 | ||
3386 | /* *(p + CST) -> ... */ | |
3387 | if (TREE_CODE (sub) == POINTER_PLUS_EXPR | |
3388 | && TREE_CODE (TREE_OPERAND (sub, 1)) == INTEGER_CST) | |
3389 | { | |
3390 | tree addr = TREE_OPERAND (sub, 0); | |
3391 | tree off = TREE_OPERAND (sub, 1); | |
3392 | tree addrtype; | |
3393 | ||
3394 | STRIP_NOPS (addr); | |
3395 | addrtype = TREE_TYPE (addr); | |
3396 | ||
3397 | /* ((foo*)&vectorfoo)[1] -> BIT_FIELD_REF<vectorfoo,...> */ | |
3398 | if (TREE_CODE (addr) == ADDR_EXPR | |
3399 | && TREE_CODE (TREE_TYPE (addrtype)) == VECTOR_TYPE | |
3400 | && useless_type_conversion_p (type, TREE_TYPE (TREE_TYPE (addrtype))) | |
3401 | && host_integerp (off, 1)) | |
3402 | { | |
3403 | unsigned HOST_WIDE_INT offset = tree_low_cst (off, 1); | |
3404 | tree part_width = TYPE_SIZE (type); | |
3405 | unsigned HOST_WIDE_INT part_widthi | |
3406 | = tree_low_cst (part_width, 0) / BITS_PER_UNIT; | |
3407 | unsigned HOST_WIDE_INT indexi = offset * BITS_PER_UNIT; | |
3408 | tree index = bitsize_int (indexi); | |
3409 | if (offset / part_widthi | |
3410 | <= TYPE_VECTOR_SUBPARTS (TREE_TYPE (addrtype))) | |
3411 | return fold_build3 (BIT_FIELD_REF, type, TREE_OPERAND (addr, 0), | |
3412 | part_width, index); | |
3413 | } | |
3414 | ||
3415 | /* ((foo*)&complexfoo)[1] -> __imag__ complexfoo */ | |
3416 | if (TREE_CODE (addr) == ADDR_EXPR | |
3417 | && TREE_CODE (TREE_TYPE (addrtype)) == COMPLEX_TYPE | |
3418 | && useless_type_conversion_p (type, TREE_TYPE (TREE_TYPE (addrtype)))) | |
3419 | { | |
3420 | tree size = TYPE_SIZE_UNIT (type); | |
3421 | if (tree_int_cst_equal (size, off)) | |
3422 | return fold_build1 (IMAGPART_EXPR, type, TREE_OPERAND (addr, 0)); | |
3423 | } | |
3424 | ||
3425 | /* *(p + CST) -> MEM_REF <p, CST>. */ | |
3426 | if (TREE_CODE (addr) != ADDR_EXPR | |
3427 | || DECL_P (TREE_OPERAND (addr, 0))) | |
3428 | return fold_build2 (MEM_REF, type, | |
3429 | addr, | |
3430 | build_int_cst_wide (ptype, | |
3431 | TREE_INT_CST_LOW (off), | |
3432 | TREE_INT_CST_HIGH (off))); | |
3433 | } | |
3434 | ||
3435 | /* *(foo *)fooarrptr => (*fooarrptr)[0] */ | |
3436 | if (TREE_CODE (TREE_TYPE (subtype)) == ARRAY_TYPE | |
3437 | && TREE_CODE (TYPE_SIZE (TREE_TYPE (TREE_TYPE (subtype)))) == INTEGER_CST | |
3438 | && useless_type_conversion_p (type, TREE_TYPE (TREE_TYPE (subtype)))) | |
3439 | { | |
3440 | tree type_domain; | |
3441 | tree min_val = size_zero_node; | |
3442 | tree osub = sub; | |
3443 | sub = gimple_fold_indirect_ref (sub); | |
3444 | if (! sub) | |
3445 | sub = build1 (INDIRECT_REF, TREE_TYPE (subtype), osub); | |
3446 | type_domain = TYPE_DOMAIN (TREE_TYPE (sub)); | |
3447 | if (type_domain && TYPE_MIN_VALUE (type_domain)) | |
3448 | min_val = TYPE_MIN_VALUE (type_domain); | |
3449 | if (TREE_CODE (min_val) == INTEGER_CST) | |
3450 | return build4 (ARRAY_REF, type, sub, min_val, NULL_TREE, NULL_TREE); | |
3451 | } | |
3452 | ||
3453 | return NULL_TREE; | |
3454 | } |