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8b57bfeb | 1 | /* String length optimization |
85ec4feb | 2 | Copyright (C) 2011-2018 Free Software Foundation, Inc. |
8b57bfeb JJ |
3 | Contributed by Jakub Jelinek <jakub@redhat.com> |
4 | ||
5 | This file is part of GCC. | |
6 | ||
7 | GCC is free software; you can redistribute it and/or modify | |
8 | it under the terms of the GNU General Public License as published by | |
9 | the Free Software Foundation; either version 3, or (at your option) | |
10 | any later version. | |
11 | ||
12 | GCC is distributed in the hope that it will be useful, | |
13 | but WITHOUT ANY WARRANTY; without even the implied warranty of | |
14 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
15 | GNU General Public License 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" | |
c7131fb2 | 24 | #include "backend.h" |
957060b5 | 25 | #include "rtl.h" |
4d648807 | 26 | #include "tree.h" |
c7131fb2 | 27 | #include "gimple.h" |
957060b5 AM |
28 | #include "alloc-pool.h" |
29 | #include "tree-pass.h" | |
c7131fb2 | 30 | #include "ssa.h" |
957060b5 AM |
31 | #include "cgraph.h" |
32 | #include "gimple-pretty-print.h" | |
cc8bea0a | 33 | #include "gimple-ssa-warn-restrict.h" |
40e23961 | 34 | #include "fold-const.h" |
d8a2d370 | 35 | #include "stor-layout.h" |
2fb9a547 AM |
36 | #include "gimple-fold.h" |
37 | #include "tree-eh.h" | |
45b0be94 | 38 | #include "gimplify.h" |
5be5c238 | 39 | #include "gimple-iterator.h" |
18f429e2 | 40 | #include "gimplify-me.h" |
d8a2d370 | 41 | #include "expr.h" |
fa9544ab | 42 | #include "tree-cfg.h" |
442b4905 | 43 | #include "tree-dfa.h" |
8b57bfeb | 44 | #include "domwalk.h" |
025d57f0 | 45 | #include "tree-ssa-alias.h" |
8b57bfeb | 46 | #include "tree-ssa-propagate.h" |
5d0d5d68 | 47 | #include "tree-ssa-strlen.h" |
8b57bfeb | 48 | #include "params.h" |
f5fc4a04 | 49 | #include "ipa-chkp.h" |
910ee068 | 50 | #include "tree-hash-traits.h" |
36b85e43 | 51 | #include "builtins.h" |
e0bd6c9f | 52 | #include "target.h" |
025d57f0 MS |
53 | #include "diagnostic-core.h" |
54 | #include "diagnostic.h" | |
55 | #include "intl.h" | |
56 | #include "attribs.h" | |
6a33d0ff | 57 | #include "calls.h" |
8b57bfeb JJ |
58 | |
59 | /* A vector indexed by SSA_NAME_VERSION. 0 means unknown, positive value | |
60 | is an index into strinfo vector, negative value stands for | |
61 | string length of a string literal (~strlen). */ | |
9771b263 | 62 | static vec<int> ssa_ver_to_stridx; |
8b57bfeb JJ |
63 | |
64 | /* Number of currently active string indexes plus one. */ | |
65 | static int max_stridx; | |
66 | ||
67 | /* String information record. */ | |
526ceb68 | 68 | struct strinfo |
8b57bfeb | 69 | { |
e3f9a279 RS |
70 | /* Number of leading characters that are known to be nonzero. This is |
71 | also the length of the string if FULL_STRING_P. | |
72 | ||
73 | The values in a list of related string pointers must be consistent; | |
74 | that is, if strinfo B comes X bytes after strinfo A, it must be | |
75 | the case that A->nonzero_chars == X + B->nonzero_chars. */ | |
76 | tree nonzero_chars; | |
8b57bfeb JJ |
77 | /* Any of the corresponding pointers for querying alias oracle. */ |
78 | tree ptr; | |
862088aa RS |
79 | /* This is used for two things: |
80 | ||
81 | - To record the statement that should be used for delayed length | |
82 | computations. We maintain the invariant that all related strinfos | |
83 | have delayed lengths or none do. | |
84 | ||
85 | - To record the malloc or calloc call that produced this result. */ | |
355fe088 | 86 | gimple *stmt; |
8b57bfeb JJ |
87 | /* Pointer to '\0' if known, if NULL, it can be computed as |
88 | ptr + length. */ | |
89 | tree endptr; | |
90 | /* Reference count. Any changes to strinfo entry possibly shared | |
91 | with dominating basic blocks need unshare_strinfo first, except | |
92 | for dont_invalidate which affects only the immediately next | |
93 | maybe_invalidate. */ | |
94 | int refcount; | |
95 | /* Copy of index. get_strinfo (si->idx) should return si; */ | |
96 | int idx; | |
97 | /* These 3 fields are for chaining related string pointers together. | |
98 | E.g. for | |
99 | bl = strlen (b); dl = strlen (d); strcpy (a, b); c = a + bl; | |
100 | strcpy (c, d); e = c + dl; | |
101 | strinfo(a) -> strinfo(c) -> strinfo(e) | |
102 | All have ->first field equal to strinfo(a)->idx and are doubly | |
103 | chained through prev/next fields. The later strinfos are required | |
104 | to point into the same string with zero or more bytes after | |
105 | the previous pointer and all bytes in between the two pointers | |
106 | must be non-zero. Functions like strcpy or memcpy are supposed | |
107 | to adjust all previous strinfo lengths, but not following strinfo | |
108 | lengths (those are uncertain, usually invalidated during | |
109 | maybe_invalidate, except when the alias oracle knows better). | |
110 | Functions like strcat on the other side adjust the whole | |
111 | related strinfo chain. | |
112 | They are updated lazily, so to use the chain the same first fields | |
113 | and si->prev->next == si->idx needs to be verified. */ | |
114 | int first; | |
115 | int next; | |
116 | int prev; | |
117 | /* A flag whether the string is known to be written in the current | |
118 | function. */ | |
119 | bool writable; | |
120 | /* A flag for the next maybe_invalidate that this strinfo shouldn't | |
121 | be invalidated. Always cleared by maybe_invalidate. */ | |
122 | bool dont_invalidate; | |
e3f9a279 RS |
123 | /* True if the string is known to be nul-terminated after NONZERO_CHARS |
124 | characters. False is useful when detecting strings that are built | |
125 | up via successive memcpys. */ | |
126 | bool full_string_p; | |
526ceb68 | 127 | }; |
8b57bfeb JJ |
128 | |
129 | /* Pool for allocating strinfo_struct entries. */ | |
526ceb68 | 130 | static object_allocator<strinfo> strinfo_pool ("strinfo pool"); |
8b57bfeb JJ |
131 | |
132 | /* Vector mapping positive string indexes to strinfo, for the | |
133 | current basic block. The first pointer in the vector is special, | |
134 | it is either NULL, meaning the vector isn't shared, or it is | |
135 | a basic block pointer to the owner basic_block if shared. | |
136 | If some other bb wants to modify the vector, the vector needs | |
137 | to be unshared first, and only the owner bb is supposed to free it. */ | |
526ceb68 | 138 | static vec<strinfo *, va_heap, vl_embed> *stridx_to_strinfo; |
8b57bfeb JJ |
139 | |
140 | /* One OFFSET->IDX mapping. */ | |
141 | struct stridxlist | |
142 | { | |
143 | struct stridxlist *next; | |
144 | HOST_WIDE_INT offset; | |
145 | int idx; | |
146 | }; | |
147 | ||
148 | /* Hash table entry, mapping a DECL to a chain of OFFSET->IDX mappings. */ | |
149 | struct decl_stridxlist_map | |
150 | { | |
151 | struct tree_map_base base; | |
152 | struct stridxlist list; | |
153 | }; | |
154 | ||
155 | /* Hash table for mapping decls to a chained list of offset -> idx | |
156 | mappings. */ | |
fb5c464a | 157 | static hash_map<tree_decl_hash, stridxlist> *decl_to_stridxlist_htab; |
8b57bfeb | 158 | |
6a33d0ff MS |
159 | /* Hash table mapping strlen calls to stridx instances describing |
160 | the calls' arguments. Non-null only when warn_stringop_truncation | |
161 | is non-zero. */ | |
025d57f0 | 162 | typedef std::pair<int, location_t> stridx_strlenloc; |
6a33d0ff | 163 | static hash_map<tree, stridx_strlenloc> *strlen_to_stridx; |
025d57f0 | 164 | |
8b57bfeb JJ |
165 | /* Obstack for struct stridxlist and struct decl_stridxlist_map. */ |
166 | static struct obstack stridx_obstack; | |
167 | ||
168 | /* Last memcpy statement if it could be adjusted if the trailing | |
169 | '\0' written is immediately overwritten, or | |
170 | *x = '\0' store that could be removed if it is immediately overwritten. */ | |
171 | struct laststmt_struct | |
172 | { | |
355fe088 | 173 | gimple *stmt; |
8b57bfeb JJ |
174 | tree len; |
175 | int stridx; | |
176 | } laststmt; | |
177 | ||
e3f9a279 | 178 | static int get_stridx_plus_constant (strinfo *, unsigned HOST_WIDE_INT, tree); |
cc8bea0a | 179 | static void handle_builtin_stxncpy (built_in_function, gimple_stmt_iterator *); |
e3f9a279 RS |
180 | |
181 | /* Return: | |
182 | ||
183 | - 1 if SI is known to start with more than OFF nonzero characters. | |
184 | ||
185 | - 0 if SI is known to start with OFF nonzero characters, | |
186 | but is not known to start with more. | |
187 | ||
188 | - -1 if SI might not start with OFF nonzero characters. */ | |
189 | ||
190 | static inline int | |
191 | compare_nonzero_chars (strinfo *si, unsigned HOST_WIDE_INT off) | |
192 | { | |
193 | if (si->nonzero_chars | |
194 | && TREE_CODE (si->nonzero_chars) == INTEGER_CST) | |
195 | return compare_tree_int (si->nonzero_chars, off); | |
196 | else | |
197 | return -1; | |
198 | } | |
199 | ||
200 | /* Return true if SI is known to be a zero-length string. */ | |
201 | ||
202 | static inline bool | |
203 | zero_length_string_p (strinfo *si) | |
204 | { | |
205 | return si->full_string_p && integer_zerop (si->nonzero_chars); | |
206 | } | |
204a913b JJ |
207 | |
208 | /* Return strinfo vector entry IDX. */ | |
209 | ||
526ceb68 | 210 | static inline strinfo * |
204a913b JJ |
211 | get_strinfo (int idx) |
212 | { | |
213 | if (vec_safe_length (stridx_to_strinfo) <= (unsigned int) idx) | |
214 | return NULL; | |
215 | return (*stridx_to_strinfo)[idx]; | |
216 | } | |
217 | ||
bde63fde RS |
218 | /* Get the next strinfo in the chain after SI, or null if none. */ |
219 | ||
220 | static inline strinfo * | |
221 | get_next_strinfo (strinfo *si) | |
222 | { | |
223 | if (si->next == 0) | |
224 | return NULL; | |
225 | strinfo *nextsi = get_strinfo (si->next); | |
226 | if (nextsi == NULL || nextsi->first != si->first || nextsi->prev != si->idx) | |
227 | return NULL; | |
228 | return nextsi; | |
229 | } | |
230 | ||
e3f9a279 RS |
231 | /* Helper function for get_stridx. Return the strinfo index of the address |
232 | of EXP, which is available in PTR if nonnull. If OFFSET_OUT, it is | |
233 | OK to return the index for some X <= &EXP and store &EXP - X in | |
234 | *OFFSET_OUT. */ | |
8b57bfeb JJ |
235 | |
236 | static int | |
e3f9a279 | 237 | get_addr_stridx (tree exp, tree ptr, unsigned HOST_WIDE_INT *offset_out) |
8b57bfeb JJ |
238 | { |
239 | HOST_WIDE_INT off; | |
5f3cd7c3 | 240 | struct stridxlist *list, *last = NULL; |
8b57bfeb JJ |
241 | tree base; |
242 | ||
c203e8a7 | 243 | if (!decl_to_stridxlist_htab) |
8b57bfeb JJ |
244 | return 0; |
245 | ||
a90c8804 RS |
246 | poly_int64 poff; |
247 | base = get_addr_base_and_unit_offset (exp, &poff); | |
248 | if (base == NULL || !DECL_P (base) || !poff.is_constant (&off)) | |
8b57bfeb JJ |
249 | return 0; |
250 | ||
1eb68d2d TS |
251 | list = decl_to_stridxlist_htab->get (base); |
252 | if (list == NULL) | |
8b57bfeb JJ |
253 | return 0; |
254 | ||
8b57bfeb JJ |
255 | do |
256 | { | |
257 | if (list->offset == off) | |
e3f9a279 RS |
258 | { |
259 | if (offset_out) | |
260 | *offset_out = 0; | |
261 | return list->idx; | |
262 | } | |
5f3cd7c3 JJ |
263 | if (list->offset > off) |
264 | return 0; | |
265 | last = list; | |
8b57bfeb JJ |
266 | list = list->next; |
267 | } | |
268 | while (list); | |
5f3cd7c3 | 269 | |
e3f9a279 | 270 | if ((offset_out || ptr) && last && last->idx > 0) |
5f3cd7c3 | 271 | { |
e3f9a279 RS |
272 | unsigned HOST_WIDE_INT rel_off |
273 | = (unsigned HOST_WIDE_INT) off - last->offset; | |
5f3cd7c3 | 274 | strinfo *si = get_strinfo (last->idx); |
e3f9a279 RS |
275 | if (si && compare_nonzero_chars (si, rel_off) >= 0) |
276 | { | |
277 | if (offset_out) | |
278 | { | |
279 | *offset_out = rel_off; | |
280 | return last->idx; | |
281 | } | |
282 | else | |
283 | return get_stridx_plus_constant (si, rel_off, ptr); | |
284 | } | |
5f3cd7c3 | 285 | } |
8b57bfeb JJ |
286 | return 0; |
287 | } | |
288 | ||
289 | /* Return string index for EXP. */ | |
290 | ||
291 | static int | |
292 | get_stridx (tree exp) | |
293 | { | |
b3c3685a | 294 | tree s, o; |
8b57bfeb JJ |
295 | |
296 | if (TREE_CODE (exp) == SSA_NAME) | |
204a913b JJ |
297 | { |
298 | if (ssa_ver_to_stridx[SSA_NAME_VERSION (exp)]) | |
299 | return ssa_ver_to_stridx[SSA_NAME_VERSION (exp)]; | |
300 | int i; | |
301 | tree e = exp; | |
302 | HOST_WIDE_INT off = 0; | |
303 | for (i = 0; i < 5; i++) | |
304 | { | |
355fe088 | 305 | gimple *def_stmt = SSA_NAME_DEF_STMT (e); |
204a913b JJ |
306 | if (!is_gimple_assign (def_stmt) |
307 | || gimple_assign_rhs_code (def_stmt) != POINTER_PLUS_EXPR) | |
308 | return 0; | |
309 | tree rhs1 = gimple_assign_rhs1 (def_stmt); | |
310 | tree rhs2 = gimple_assign_rhs2 (def_stmt); | |
311 | if (TREE_CODE (rhs1) != SSA_NAME | |
312 | || !tree_fits_shwi_p (rhs2)) | |
313 | return 0; | |
314 | HOST_WIDE_INT this_off = tree_to_shwi (rhs2); | |
315 | if (this_off < 0) | |
316 | return 0; | |
317 | off = (unsigned HOST_WIDE_INT) off + this_off; | |
318 | if (off < 0) | |
319 | return 0; | |
320 | if (ssa_ver_to_stridx[SSA_NAME_VERSION (rhs1)]) | |
321 | { | |
526ceb68 | 322 | strinfo *si |
204a913b | 323 | = get_strinfo (ssa_ver_to_stridx[SSA_NAME_VERSION (rhs1)]); |
e3f9a279 | 324 | if (si && compare_nonzero_chars (si, off) >= 0) |
204a913b JJ |
325 | return get_stridx_plus_constant (si, off, exp); |
326 | } | |
327 | e = rhs1; | |
328 | } | |
329 | return 0; | |
330 | } | |
8b57bfeb JJ |
331 | |
332 | if (TREE_CODE (exp) == ADDR_EXPR) | |
333 | { | |
e3f9a279 | 334 | int idx = get_addr_stridx (TREE_OPERAND (exp, 0), exp, NULL); |
8b57bfeb JJ |
335 | if (idx != 0) |
336 | return idx; | |
337 | } | |
338 | ||
b3c3685a JJ |
339 | s = string_constant (exp, &o); |
340 | if (s != NULL_TREE | |
9541ffee | 341 | && (o == NULL_TREE || tree_fits_shwi_p (o)) |
b3c3685a | 342 | && TREE_STRING_LENGTH (s) > 0) |
8b57bfeb | 343 | { |
9439e9a1 | 344 | HOST_WIDE_INT offset = o ? tree_to_shwi (o) : 0; |
b3c3685a JJ |
345 | const char *p = TREE_STRING_POINTER (s); |
346 | int max = TREE_STRING_LENGTH (s) - 1; | |
347 | ||
348 | if (p[max] == '\0' && offset >= 0 && offset <= max) | |
349 | return ~(int) strlen (p + offset); | |
8b57bfeb JJ |
350 | } |
351 | return 0; | |
352 | } | |
353 | ||
354 | /* Return true if strinfo vector is shared with the immediate dominator. */ | |
355 | ||
356 | static inline bool | |
357 | strinfo_shared (void) | |
358 | { | |
9771b263 DN |
359 | return vec_safe_length (stridx_to_strinfo) |
360 | && (*stridx_to_strinfo)[0] != NULL; | |
8b57bfeb JJ |
361 | } |
362 | ||
363 | /* Unshare strinfo vector that is shared with the immediate dominator. */ | |
364 | ||
365 | static void | |
366 | unshare_strinfo_vec (void) | |
367 | { | |
526ceb68 | 368 | strinfo *si; |
8b57bfeb JJ |
369 | unsigned int i = 0; |
370 | ||
371 | gcc_assert (strinfo_shared ()); | |
9771b263 DN |
372 | stridx_to_strinfo = vec_safe_copy (stridx_to_strinfo); |
373 | for (i = 1; vec_safe_iterate (stridx_to_strinfo, i, &si); ++i) | |
8b57bfeb JJ |
374 | if (si != NULL) |
375 | si->refcount++; | |
9771b263 | 376 | (*stridx_to_strinfo)[0] = NULL; |
8b57bfeb JJ |
377 | } |
378 | ||
379 | /* Attempt to create a string index for exp, ADDR_EXPR's operand. | |
380 | Return a pointer to the location where the string index can | |
381 | be stored (if 0) or is stored, or NULL if this can't be tracked. */ | |
382 | ||
383 | static int * | |
384 | addr_stridxptr (tree exp) | |
385 | { | |
8b57bfeb JJ |
386 | HOST_WIDE_INT off; |
387 | ||
a90c8804 RS |
388 | poly_int64 poff; |
389 | tree base = get_addr_base_and_unit_offset (exp, &poff); | |
390 | if (base == NULL_TREE || !DECL_P (base) || !poff.is_constant (&off)) | |
8b57bfeb JJ |
391 | return NULL; |
392 | ||
c203e8a7 | 393 | if (!decl_to_stridxlist_htab) |
8b57bfeb | 394 | { |
1eb68d2d | 395 | decl_to_stridxlist_htab |
fb5c464a | 396 | = new hash_map<tree_decl_hash, stridxlist> (64); |
8b57bfeb JJ |
397 | gcc_obstack_init (&stridx_obstack); |
398 | } | |
1eb68d2d TS |
399 | |
400 | bool existed; | |
401 | stridxlist *list = &decl_to_stridxlist_htab->get_or_insert (base, &existed); | |
402 | if (existed) | |
8b57bfeb JJ |
403 | { |
404 | int i; | |
5f3cd7c3 JJ |
405 | stridxlist *before = NULL; |
406 | for (i = 0; i < 32; i++) | |
8b57bfeb JJ |
407 | { |
408 | if (list->offset == off) | |
409 | return &list->idx; | |
5f3cd7c3 JJ |
410 | if (list->offset > off && before == NULL) |
411 | before = list; | |
8b57bfeb JJ |
412 | if (list->next == NULL) |
413 | break; | |
5f3cd7c3 | 414 | list = list->next; |
8b57bfeb | 415 | } |
5f3cd7c3 | 416 | if (i == 32) |
8b57bfeb | 417 | return NULL; |
5f3cd7c3 JJ |
418 | if (before) |
419 | { | |
420 | list = before; | |
421 | before = XOBNEW (&stridx_obstack, struct stridxlist); | |
422 | *before = *list; | |
423 | list->next = before; | |
424 | list->offset = off; | |
425 | list->idx = 0; | |
426 | return &list->idx; | |
427 | } | |
8b57bfeb JJ |
428 | list->next = XOBNEW (&stridx_obstack, struct stridxlist); |
429 | list = list->next; | |
430 | } | |
1eb68d2d | 431 | |
8b57bfeb JJ |
432 | list->next = NULL; |
433 | list->offset = off; | |
434 | list->idx = 0; | |
435 | return &list->idx; | |
436 | } | |
437 | ||
438 | /* Create a new string index, or return 0 if reached limit. */ | |
439 | ||
440 | static int | |
441 | new_stridx (tree exp) | |
442 | { | |
443 | int idx; | |
444 | if (max_stridx >= PARAM_VALUE (PARAM_MAX_TRACKED_STRLENS)) | |
445 | return 0; | |
446 | if (TREE_CODE (exp) == SSA_NAME) | |
447 | { | |
448 | if (SSA_NAME_OCCURS_IN_ABNORMAL_PHI (exp)) | |
449 | return 0; | |
450 | idx = max_stridx++; | |
9771b263 | 451 | ssa_ver_to_stridx[SSA_NAME_VERSION (exp)] = idx; |
8b57bfeb JJ |
452 | return idx; |
453 | } | |
454 | if (TREE_CODE (exp) == ADDR_EXPR) | |
455 | { | |
456 | int *pidx = addr_stridxptr (TREE_OPERAND (exp, 0)); | |
457 | if (pidx != NULL) | |
458 | { | |
459 | gcc_assert (*pidx == 0); | |
460 | *pidx = max_stridx++; | |
461 | return *pidx; | |
462 | } | |
463 | } | |
464 | return 0; | |
465 | } | |
466 | ||
467 | /* Like new_stridx, but for ADDR_EXPR's operand instead. */ | |
468 | ||
469 | static int | |
470 | new_addr_stridx (tree exp) | |
471 | { | |
472 | int *pidx; | |
473 | if (max_stridx >= PARAM_VALUE (PARAM_MAX_TRACKED_STRLENS)) | |
474 | return 0; | |
475 | pidx = addr_stridxptr (exp); | |
476 | if (pidx != NULL) | |
477 | { | |
478 | gcc_assert (*pidx == 0); | |
479 | *pidx = max_stridx++; | |
480 | return *pidx; | |
481 | } | |
482 | return 0; | |
483 | } | |
484 | ||
485 | /* Create a new strinfo. */ | |
486 | ||
526ceb68 | 487 | static strinfo * |
e3f9a279 | 488 | new_strinfo (tree ptr, int idx, tree nonzero_chars, bool full_string_p) |
8b57bfeb | 489 | { |
526ceb68 | 490 | strinfo *si = strinfo_pool.allocate (); |
e3f9a279 | 491 | si->nonzero_chars = nonzero_chars; |
8b57bfeb JJ |
492 | si->ptr = ptr; |
493 | si->stmt = NULL; | |
494 | si->endptr = NULL_TREE; | |
495 | si->refcount = 1; | |
496 | si->idx = idx; | |
497 | si->first = 0; | |
498 | si->prev = 0; | |
499 | si->next = 0; | |
500 | si->writable = false; | |
501 | si->dont_invalidate = false; | |
e3f9a279 | 502 | si->full_string_p = full_string_p; |
8b57bfeb JJ |
503 | return si; |
504 | } | |
505 | ||
506 | /* Decrease strinfo refcount and free it if not referenced anymore. */ | |
507 | ||
508 | static inline void | |
526ceb68 | 509 | free_strinfo (strinfo *si) |
8b57bfeb JJ |
510 | { |
511 | if (si && --si->refcount == 0) | |
33e7d32e | 512 | strinfo_pool.remove (si); |
8b57bfeb JJ |
513 | } |
514 | ||
8b57bfeb JJ |
515 | /* Set strinfo in the vector entry IDX to SI. */ |
516 | ||
517 | static inline void | |
526ceb68 | 518 | set_strinfo (int idx, strinfo *si) |
8b57bfeb | 519 | { |
9771b263 | 520 | if (vec_safe_length (stridx_to_strinfo) && (*stridx_to_strinfo)[0]) |
8b57bfeb | 521 | unshare_strinfo_vec (); |
9771b263 DN |
522 | if (vec_safe_length (stridx_to_strinfo) <= (unsigned int) idx) |
523 | vec_safe_grow_cleared (stridx_to_strinfo, idx + 1); | |
524 | (*stridx_to_strinfo)[idx] = si; | |
8b57bfeb JJ |
525 | } |
526 | ||
862088aa RS |
527 | /* Return the first strinfo in the related strinfo chain |
528 | if all strinfos in between belong to the chain, otherwise NULL. */ | |
529 | ||
530 | static strinfo * | |
531 | verify_related_strinfos (strinfo *origsi) | |
532 | { | |
533 | strinfo *si = origsi, *psi; | |
534 | ||
535 | if (origsi->first == 0) | |
536 | return NULL; | |
537 | for (; si->prev; si = psi) | |
538 | { | |
539 | if (si->first != origsi->first) | |
540 | return NULL; | |
541 | psi = get_strinfo (si->prev); | |
542 | if (psi == NULL) | |
543 | return NULL; | |
544 | if (psi->next != si->idx) | |
545 | return NULL; | |
546 | } | |
547 | if (si->idx != si->first) | |
548 | return NULL; | |
549 | return si; | |
550 | } | |
551 | ||
552 | /* Set SI's endptr to ENDPTR and compute its length based on SI->ptr. | |
553 | Use LOC for folding. */ | |
554 | ||
555 | static void | |
556 | set_endptr_and_length (location_t loc, strinfo *si, tree endptr) | |
557 | { | |
558 | si->endptr = endptr; | |
559 | si->stmt = NULL; | |
560 | tree start_as_size = fold_convert_loc (loc, size_type_node, si->ptr); | |
561 | tree end_as_size = fold_convert_loc (loc, size_type_node, endptr); | |
e3f9a279 RS |
562 | si->nonzero_chars = fold_build2_loc (loc, MINUS_EXPR, size_type_node, |
563 | end_as_size, start_as_size); | |
564 | si->full_string_p = true; | |
862088aa RS |
565 | } |
566 | ||
8b57bfeb JJ |
567 | /* Return string length, or NULL if it can't be computed. */ |
568 | ||
569 | static tree | |
526ceb68 | 570 | get_string_length (strinfo *si) |
8b57bfeb | 571 | { |
e3f9a279 RS |
572 | if (si->nonzero_chars) |
573 | return si->full_string_p ? si->nonzero_chars : NULL; | |
8b57bfeb JJ |
574 | |
575 | if (si->stmt) | |
576 | { | |
355fe088 | 577 | gimple *stmt = si->stmt, *lenstmt; |
f5fc4a04 | 578 | bool with_bounds = gimple_call_with_bounds_p (stmt); |
83d5977e | 579 | tree callee, lhs, fn, tem; |
8b57bfeb JJ |
580 | location_t loc; |
581 | gimple_stmt_iterator gsi; | |
582 | ||
583 | gcc_assert (is_gimple_call (stmt)); | |
584 | callee = gimple_call_fndecl (stmt); | |
585 | gcc_assert (callee && DECL_BUILT_IN_CLASS (callee) == BUILT_IN_NORMAL); | |
586 | lhs = gimple_call_lhs (stmt); | |
8b57bfeb JJ |
587 | /* unshare_strinfo is intentionally not called here. The (delayed) |
588 | transformation of strcpy or strcat into stpcpy is done at the place | |
589 | of the former strcpy/strcat call and so can affect all the strinfos | |
590 | with the same stmt. If they were unshared before and transformation | |
591 | has been already done, the handling of BUILT_IN_STPCPY{,_CHK} should | |
592 | just compute the right length. */ | |
593 | switch (DECL_FUNCTION_CODE (callee)) | |
594 | { | |
595 | case BUILT_IN_STRCAT: | |
596 | case BUILT_IN_STRCAT_CHK: | |
f5fc4a04 IE |
597 | case BUILT_IN_STRCAT_CHKP: |
598 | case BUILT_IN_STRCAT_CHK_CHKP: | |
8b57bfeb | 599 | gsi = gsi_for_stmt (stmt); |
e79983f4 | 600 | fn = builtin_decl_implicit (BUILT_IN_STRLEN); |
8b57bfeb | 601 | gcc_assert (lhs == NULL_TREE); |
8b57bfeb | 602 | tem = unshare_expr (gimple_call_arg (stmt, 0)); |
f5fc4a04 IE |
603 | if (with_bounds) |
604 | { | |
605 | lenstmt = gimple_build_call (chkp_maybe_create_clone (fn)->decl, | |
606 | 2, tem, gimple_call_arg (stmt, 1)); | |
607 | gimple_call_set_with_bounds (lenstmt, true); | |
608 | } | |
609 | else | |
610 | lenstmt = gimple_build_call (fn, 1, tem); | |
83d5977e | 611 | lhs = make_ssa_name (TREE_TYPE (TREE_TYPE (fn)), lenstmt); |
8b57bfeb JJ |
612 | gimple_call_set_lhs (lenstmt, lhs); |
613 | gimple_set_vuse (lenstmt, gimple_vuse (stmt)); | |
614 | gsi_insert_before (&gsi, lenstmt, GSI_SAME_STMT); | |
8b57bfeb | 615 | tem = gimple_call_arg (stmt, 0); |
33960e2e TG |
616 | if (!ptrofftype_p (TREE_TYPE (lhs))) |
617 | { | |
618 | lhs = convert_to_ptrofftype (lhs); | |
619 | lhs = force_gimple_operand_gsi (&gsi, lhs, true, NULL_TREE, | |
620 | true, GSI_SAME_STMT); | |
621 | } | |
0d0e4a03 JJ |
622 | lenstmt = gimple_build_assign |
623 | (make_ssa_name (TREE_TYPE (gimple_call_arg (stmt, 0))), | |
624 | POINTER_PLUS_EXPR,tem, lhs); | |
8b57bfeb JJ |
625 | gsi_insert_before (&gsi, lenstmt, GSI_SAME_STMT); |
626 | gimple_call_set_arg (stmt, 0, gimple_assign_lhs (lenstmt)); | |
627 | lhs = NULL_TREE; | |
628 | /* FALLTHRU */ | |
629 | case BUILT_IN_STRCPY: | |
630 | case BUILT_IN_STRCPY_CHK: | |
f5fc4a04 IE |
631 | case BUILT_IN_STRCPY_CHKP: |
632 | case BUILT_IN_STRCPY_CHK_CHKP: | |
1e762c6a | 633 | gcc_assert (builtin_decl_implicit_p (BUILT_IN_STPCPY)); |
f5fc4a04 | 634 | if (gimple_call_num_args (stmt) == (with_bounds ? 4 : 2)) |
e79983f4 | 635 | fn = builtin_decl_implicit (BUILT_IN_STPCPY); |
8b57bfeb | 636 | else |
e79983f4 | 637 | fn = builtin_decl_explicit (BUILT_IN_STPCPY_CHK); |
f5fc4a04 IE |
638 | if (with_bounds) |
639 | fn = chkp_maybe_create_clone (fn)->decl; | |
8b57bfeb JJ |
640 | gcc_assert (lhs == NULL_TREE); |
641 | if (dump_file && (dump_flags & TDF_DETAILS) != 0) | |
642 | { | |
643 | fprintf (dump_file, "Optimizing: "); | |
644 | print_gimple_stmt (dump_file, stmt, 0, TDF_SLIM); | |
645 | } | |
646 | gimple_call_set_fndecl (stmt, fn); | |
83d5977e | 647 | lhs = make_ssa_name (TREE_TYPE (TREE_TYPE (fn)), stmt); |
8b57bfeb JJ |
648 | gimple_call_set_lhs (stmt, lhs); |
649 | update_stmt (stmt); | |
650 | if (dump_file && (dump_flags & TDF_DETAILS) != 0) | |
651 | { | |
652 | fprintf (dump_file, "into: "); | |
653 | print_gimple_stmt (dump_file, stmt, 0, TDF_SLIM); | |
654 | } | |
655 | /* FALLTHRU */ | |
656 | case BUILT_IN_STPCPY: | |
657 | case BUILT_IN_STPCPY_CHK: | |
f5fc4a04 IE |
658 | case BUILT_IN_STPCPY_CHKP: |
659 | case BUILT_IN_STPCPY_CHK_CHKP: | |
8b57bfeb JJ |
660 | gcc_assert (lhs != NULL_TREE); |
661 | loc = gimple_location (stmt); | |
862088aa RS |
662 | set_endptr_and_length (loc, si, lhs); |
663 | for (strinfo *chainsi = verify_related_strinfos (si); | |
664 | chainsi != NULL; | |
665 | chainsi = get_next_strinfo (chainsi)) | |
e3f9a279 | 666 | if (chainsi->nonzero_chars == NULL) |
862088aa | 667 | set_endptr_and_length (loc, chainsi, lhs); |
8b57bfeb | 668 | break; |
24314386 MG |
669 | case BUILT_IN_MALLOC: |
670 | break; | |
e3f9a279 | 671 | /* BUILT_IN_CALLOC always has si->nonzero_chars set. */ |
8b57bfeb JJ |
672 | default: |
673 | gcc_unreachable (); | |
674 | break; | |
675 | } | |
676 | } | |
677 | ||
e3f9a279 | 678 | return si->nonzero_chars; |
8b57bfeb JJ |
679 | } |
680 | ||
681 | /* Invalidate string length information for strings whose length | |
682 | might change due to stores in stmt. */ | |
683 | ||
684 | static bool | |
355fe088 | 685 | maybe_invalidate (gimple *stmt) |
8b57bfeb | 686 | { |
526ceb68 | 687 | strinfo *si; |
8b57bfeb JJ |
688 | unsigned int i; |
689 | bool nonempty = false; | |
690 | ||
9771b263 | 691 | for (i = 1; vec_safe_iterate (stridx_to_strinfo, i, &si); ++i) |
8b57bfeb JJ |
692 | if (si != NULL) |
693 | { | |
694 | if (!si->dont_invalidate) | |
695 | { | |
696 | ao_ref r; | |
e3f9a279 | 697 | /* Do not use si->nonzero_chars. */ |
8b57bfeb JJ |
698 | ao_ref_init_from_ptr_and_size (&r, si->ptr, NULL_TREE); |
699 | if (stmt_may_clobber_ref_p_1 (stmt, &r)) | |
700 | { | |
701 | set_strinfo (i, NULL); | |
702 | free_strinfo (si); | |
703 | continue; | |
704 | } | |
705 | } | |
706 | si->dont_invalidate = false; | |
707 | nonempty = true; | |
708 | } | |
709 | return nonempty; | |
710 | } | |
711 | ||
204a913b | 712 | /* Unshare strinfo record SI, if it has refcount > 1 or |
8b57bfeb JJ |
713 | if stridx_to_strinfo vector is shared with some other |
714 | bbs. */ | |
715 | ||
526ceb68 TS |
716 | static strinfo * |
717 | unshare_strinfo (strinfo *si) | |
8b57bfeb | 718 | { |
526ceb68 | 719 | strinfo *nsi; |
8b57bfeb JJ |
720 | |
721 | if (si->refcount == 1 && !strinfo_shared ()) | |
722 | return si; | |
723 | ||
e3f9a279 | 724 | nsi = new_strinfo (si->ptr, si->idx, si->nonzero_chars, si->full_string_p); |
8b57bfeb JJ |
725 | nsi->stmt = si->stmt; |
726 | nsi->endptr = si->endptr; | |
727 | nsi->first = si->first; | |
728 | nsi->prev = si->prev; | |
729 | nsi->next = si->next; | |
730 | nsi->writable = si->writable; | |
731 | set_strinfo (si->idx, nsi); | |
732 | free_strinfo (si); | |
733 | return nsi; | |
734 | } | |
735 | ||
204a913b JJ |
736 | /* Attempt to create a new strinfo for BASESI + OFF, or find existing |
737 | strinfo if there is any. Return it's idx, or 0 if no strinfo has | |
738 | been created. */ | |
739 | ||
740 | static int | |
e3f9a279 RS |
741 | get_stridx_plus_constant (strinfo *basesi, unsigned HOST_WIDE_INT off, |
742 | tree ptr) | |
204a913b | 743 | { |
5f3cd7c3 | 744 | if (TREE_CODE (ptr) == SSA_NAME && SSA_NAME_OCCURS_IN_ABNORMAL_PHI (ptr)) |
204a913b JJ |
745 | return 0; |
746 | ||
e3f9a279 RS |
747 | if (compare_nonzero_chars (basesi, off) < 0 |
748 | || !tree_fits_uhwi_p (basesi->nonzero_chars)) | |
204a913b JJ |
749 | return 0; |
750 | ||
e3f9a279 RS |
751 | unsigned HOST_WIDE_INT nonzero_chars |
752 | = tree_to_uhwi (basesi->nonzero_chars) - off; | |
526ceb68 | 753 | strinfo *si = basesi, *chainsi; |
204a913b JJ |
754 | if (si->first || si->prev || si->next) |
755 | si = verify_related_strinfos (basesi); | |
756 | if (si == NULL | |
e3f9a279 RS |
757 | || si->nonzero_chars == NULL_TREE |
758 | || TREE_CODE (si->nonzero_chars) != INTEGER_CST) | |
204a913b JJ |
759 | return 0; |
760 | ||
5f3cd7c3 JJ |
761 | if (TREE_CODE (ptr) == SSA_NAME |
762 | && ssa_ver_to_stridx.length () <= SSA_NAME_VERSION (ptr)) | |
204a913b JJ |
763 | ssa_ver_to_stridx.safe_grow_cleared (num_ssa_names); |
764 | ||
e3f9a279 | 765 | gcc_checking_assert (compare_tree_int (si->nonzero_chars, off) != -1); |
204a913b JJ |
766 | for (chainsi = si; chainsi->next; chainsi = si) |
767 | { | |
bde63fde | 768 | si = get_next_strinfo (chainsi); |
204a913b | 769 | if (si == NULL |
e3f9a279 RS |
770 | || si->nonzero_chars == NULL_TREE |
771 | || TREE_CODE (si->nonzero_chars) != INTEGER_CST) | |
204a913b | 772 | break; |
e3f9a279 | 773 | int r = compare_tree_int (si->nonzero_chars, nonzero_chars); |
204a913b JJ |
774 | if (r != 1) |
775 | { | |
776 | if (r == 0) | |
777 | { | |
55a0f21a JJ |
778 | if (TREE_CODE (ptr) == SSA_NAME) |
779 | ssa_ver_to_stridx[SSA_NAME_VERSION (ptr)] = si->idx; | |
780 | else | |
781 | { | |
782 | int *pidx = addr_stridxptr (TREE_OPERAND (ptr, 0)); | |
783 | if (pidx != NULL && *pidx == 0) | |
784 | *pidx = si->idx; | |
785 | } | |
204a913b JJ |
786 | return si->idx; |
787 | } | |
788 | break; | |
789 | } | |
790 | } | |
791 | ||
792 | int idx = new_stridx (ptr); | |
793 | if (idx == 0) | |
794 | return 0; | |
e3f9a279 RS |
795 | si = new_strinfo (ptr, idx, build_int_cst (size_type_node, nonzero_chars), |
796 | basesi->full_string_p); | |
204a913b JJ |
797 | set_strinfo (idx, si); |
798 | if (chainsi->next) | |
799 | { | |
526ceb68 | 800 | strinfo *nextsi = unshare_strinfo (get_strinfo (chainsi->next)); |
204a913b JJ |
801 | si->next = nextsi->idx; |
802 | nextsi->prev = idx; | |
803 | } | |
804 | chainsi = unshare_strinfo (chainsi); | |
805 | if (chainsi->first == 0) | |
806 | chainsi->first = chainsi->idx; | |
807 | chainsi->next = idx; | |
e3f9a279 | 808 | if (chainsi->endptr == NULL_TREE && zero_length_string_p (si)) |
204a913b JJ |
809 | chainsi->endptr = ptr; |
810 | si->endptr = chainsi->endptr; | |
811 | si->prev = chainsi->idx; | |
812 | si->first = chainsi->first; | |
813 | si->writable = chainsi->writable; | |
814 | return si->idx; | |
815 | } | |
816 | ||
8b57bfeb JJ |
817 | /* Note that PTR, a pointer SSA_NAME initialized in the current stmt, points |
818 | to a zero-length string and if possible chain it to a related strinfo | |
819 | chain whose part is or might be CHAINSI. */ | |
820 | ||
526ceb68 TS |
821 | static strinfo * |
822 | zero_length_string (tree ptr, strinfo *chainsi) | |
8b57bfeb | 823 | { |
526ceb68 | 824 | strinfo *si; |
8b57bfeb | 825 | int idx; |
204a913b JJ |
826 | if (ssa_ver_to_stridx.length () <= SSA_NAME_VERSION (ptr)) |
827 | ssa_ver_to_stridx.safe_grow_cleared (num_ssa_names); | |
8b57bfeb | 828 | gcc_checking_assert (TREE_CODE (ptr) == SSA_NAME |
204a913b | 829 | && ssa_ver_to_stridx[SSA_NAME_VERSION (ptr)] == 0); |
8b57bfeb JJ |
830 | |
831 | if (SSA_NAME_OCCURS_IN_ABNORMAL_PHI (ptr)) | |
832 | return NULL; | |
833 | if (chainsi != NULL) | |
834 | { | |
835 | si = verify_related_strinfos (chainsi); | |
836 | if (si) | |
837 | { | |
bde63fde | 838 | do |
8b57bfeb | 839 | { |
862088aa | 840 | /* We shouldn't mix delayed and non-delayed lengths. */ |
e3f9a279 | 841 | gcc_assert (si->full_string_p); |
bde63fde | 842 | if (si->endptr == NULL_TREE) |
8b57bfeb | 843 | { |
bde63fde RS |
844 | si = unshare_strinfo (si); |
845 | si->endptr = ptr; | |
8b57bfeb | 846 | } |
bde63fde RS |
847 | chainsi = si; |
848 | si = get_next_strinfo (si); | |
8b57bfeb | 849 | } |
bde63fde | 850 | while (si != NULL); |
e3f9a279 | 851 | if (zero_length_string_p (chainsi)) |
8b57bfeb JJ |
852 | { |
853 | if (chainsi->next) | |
854 | { | |
855 | chainsi = unshare_strinfo (chainsi); | |
856 | chainsi->next = 0; | |
857 | } | |
9771b263 | 858 | ssa_ver_to_stridx[SSA_NAME_VERSION (ptr)] = chainsi->idx; |
8b57bfeb JJ |
859 | return chainsi; |
860 | } | |
861 | } | |
862088aa | 862 | else |
8b57bfeb | 863 | { |
862088aa | 864 | /* We shouldn't mix delayed and non-delayed lengths. */ |
e3f9a279 | 865 | gcc_assert (chainsi->full_string_p); |
862088aa RS |
866 | if (chainsi->first || chainsi->prev || chainsi->next) |
867 | { | |
868 | chainsi = unshare_strinfo (chainsi); | |
869 | chainsi->first = 0; | |
870 | chainsi->prev = 0; | |
871 | chainsi->next = 0; | |
872 | } | |
8b57bfeb JJ |
873 | } |
874 | } | |
875 | idx = new_stridx (ptr); | |
876 | if (idx == 0) | |
877 | return NULL; | |
e3f9a279 | 878 | si = new_strinfo (ptr, idx, build_int_cst (size_type_node, 0), true); |
8b57bfeb JJ |
879 | set_strinfo (idx, si); |
880 | si->endptr = ptr; | |
881 | if (chainsi != NULL) | |
882 | { | |
883 | chainsi = unshare_strinfo (chainsi); | |
884 | if (chainsi->first == 0) | |
885 | chainsi->first = chainsi->idx; | |
886 | chainsi->next = idx; | |
93a90db6 AK |
887 | if (chainsi->endptr == NULL_TREE) |
888 | chainsi->endptr = ptr; | |
8b57bfeb JJ |
889 | si->prev = chainsi->idx; |
890 | si->first = chainsi->first; | |
891 | si->writable = chainsi->writable; | |
892 | } | |
893 | return si; | |
894 | } | |
895 | ||
e3f9a279 RS |
896 | /* For strinfo ORIGSI whose length has been just updated, adjust other |
897 | related strinfos so that they match the new ORIGSI. This involves: | |
898 | ||
899 | - adding ADJ to the nonzero_chars fields | |
900 | - copying full_string_p from the new ORIGSI. */ | |
8b57bfeb JJ |
901 | |
902 | static void | |
526ceb68 | 903 | adjust_related_strinfos (location_t loc, strinfo *origsi, tree adj) |
8b57bfeb | 904 | { |
526ceb68 | 905 | strinfo *si = verify_related_strinfos (origsi); |
8b57bfeb JJ |
906 | |
907 | if (si == NULL) | |
908 | return; | |
909 | ||
910 | while (1) | |
911 | { | |
526ceb68 | 912 | strinfo *nsi; |
8b57bfeb JJ |
913 | |
914 | if (si != origsi) | |
915 | { | |
916 | tree tem; | |
917 | ||
918 | si = unshare_strinfo (si); | |
862088aa RS |
919 | /* We shouldn't see delayed lengths here; the caller must have |
920 | calculated the old length in order to calculate the | |
921 | adjustment. */ | |
e3f9a279 RS |
922 | gcc_assert (si->nonzero_chars); |
923 | tem = fold_convert_loc (loc, TREE_TYPE (si->nonzero_chars), adj); | |
924 | si->nonzero_chars = fold_build2_loc (loc, PLUS_EXPR, | |
925 | TREE_TYPE (si->nonzero_chars), | |
926 | si->nonzero_chars, tem); | |
927 | si->full_string_p = origsi->full_string_p; | |
93a90db6 | 928 | |
8b57bfeb JJ |
929 | si->endptr = NULL_TREE; |
930 | si->dont_invalidate = true; | |
931 | } | |
bde63fde RS |
932 | nsi = get_next_strinfo (si); |
933 | if (nsi == NULL) | |
8b57bfeb JJ |
934 | return; |
935 | si = nsi; | |
936 | } | |
937 | } | |
938 | ||
939 | /* Find if there are other SSA_NAME pointers equal to PTR | |
940 | for which we don't track their string lengths yet. If so, use | |
941 | IDX for them. */ | |
942 | ||
943 | static void | |
944 | find_equal_ptrs (tree ptr, int idx) | |
945 | { | |
946 | if (TREE_CODE (ptr) != SSA_NAME) | |
947 | return; | |
948 | while (1) | |
949 | { | |
355fe088 | 950 | gimple *stmt = SSA_NAME_DEF_STMT (ptr); |
8b57bfeb JJ |
951 | if (!is_gimple_assign (stmt)) |
952 | return; | |
953 | ptr = gimple_assign_rhs1 (stmt); | |
954 | switch (gimple_assign_rhs_code (stmt)) | |
955 | { | |
956 | case SSA_NAME: | |
957 | break; | |
97246d78 JJ |
958 | CASE_CONVERT: |
959 | if (!POINTER_TYPE_P (TREE_TYPE (ptr))) | |
960 | return; | |
961 | if (TREE_CODE (ptr) == SSA_NAME) | |
962 | break; | |
963 | if (TREE_CODE (ptr) != ADDR_EXPR) | |
964 | return; | |
965 | /* FALLTHRU */ | |
8b57bfeb JJ |
966 | case ADDR_EXPR: |
967 | { | |
968 | int *pidx = addr_stridxptr (TREE_OPERAND (ptr, 0)); | |
969 | if (pidx != NULL && *pidx == 0) | |
970 | *pidx = idx; | |
971 | return; | |
972 | } | |
8b57bfeb JJ |
973 | default: |
974 | return; | |
975 | } | |
976 | ||
977 | /* We might find an endptr created in this pass. Grow the | |
978 | vector in that case. */ | |
9771b263 DN |
979 | if (ssa_ver_to_stridx.length () <= SSA_NAME_VERSION (ptr)) |
980 | ssa_ver_to_stridx.safe_grow_cleared (num_ssa_names); | |
8b57bfeb | 981 | |
9771b263 | 982 | if (ssa_ver_to_stridx[SSA_NAME_VERSION (ptr)] != 0) |
8b57bfeb | 983 | return; |
9771b263 | 984 | ssa_ver_to_stridx[SSA_NAME_VERSION (ptr)] = idx; |
8b57bfeb JJ |
985 | } |
986 | } | |
987 | ||
0ad84f34 JJ |
988 | /* Return true if STMT is a call to a builtin function with the right |
989 | arguments and attributes that should be considered for optimization | |
990 | by this pass. */ | |
991 | ||
992 | static bool | |
993 | valid_builtin_call (gimple *stmt) | |
994 | { | |
995 | if (!gimple_call_builtin_p (stmt, BUILT_IN_NORMAL)) | |
996 | return false; | |
997 | ||
998 | tree callee = gimple_call_fndecl (stmt); | |
999 | switch (DECL_FUNCTION_CODE (callee)) | |
1000 | { | |
1001 | case BUILT_IN_MEMCMP: | |
1002 | case BUILT_IN_MEMCMP_EQ: | |
1003 | case BUILT_IN_STRCHR: | |
1004 | case BUILT_IN_STRCHR_CHKP: | |
1005 | case BUILT_IN_STRLEN: | |
1006 | case BUILT_IN_STRLEN_CHKP: | |
1007 | /* The above functions should be pure. Punt if they aren't. */ | |
1008 | if (gimple_vdef (stmt) || gimple_vuse (stmt) == NULL_TREE) | |
1009 | return false; | |
1010 | break; | |
1011 | ||
1012 | case BUILT_IN_CALLOC: | |
1013 | case BUILT_IN_MALLOC: | |
1014 | case BUILT_IN_MEMCPY: | |
1015 | case BUILT_IN_MEMCPY_CHK: | |
1016 | case BUILT_IN_MEMCPY_CHKP: | |
1017 | case BUILT_IN_MEMCPY_CHK_CHKP: | |
1018 | case BUILT_IN_MEMPCPY: | |
1019 | case BUILT_IN_MEMPCPY_CHK: | |
1020 | case BUILT_IN_MEMPCPY_CHKP: | |
1021 | case BUILT_IN_MEMPCPY_CHK_CHKP: | |
1022 | case BUILT_IN_MEMSET: | |
1023 | case BUILT_IN_STPCPY: | |
1024 | case BUILT_IN_STPCPY_CHK: | |
1025 | case BUILT_IN_STPCPY_CHKP: | |
1026 | case BUILT_IN_STPCPY_CHK_CHKP: | |
1027 | case BUILT_IN_STRCAT: | |
1028 | case BUILT_IN_STRCAT_CHK: | |
1029 | case BUILT_IN_STRCAT_CHKP: | |
1030 | case BUILT_IN_STRCAT_CHK_CHKP: | |
1031 | case BUILT_IN_STRCPY: | |
1032 | case BUILT_IN_STRCPY_CHK: | |
1033 | case BUILT_IN_STRCPY_CHKP: | |
1034 | case BUILT_IN_STRCPY_CHK_CHKP: | |
1035 | /* The above functions should be neither const nor pure. Punt if they | |
1036 | aren't. */ | |
1037 | if (gimple_vdef (stmt) == NULL_TREE || gimple_vuse (stmt) == NULL_TREE) | |
1038 | return false; | |
1039 | break; | |
1040 | ||
1041 | default: | |
1042 | break; | |
1043 | } | |
1044 | ||
1045 | return true; | |
1046 | } | |
1047 | ||
8b57bfeb JJ |
1048 | /* If the last .MEM setter statement before STMT is |
1049 | memcpy (x, y, strlen (y) + 1), the only .MEM use of it is STMT | |
1050 | and STMT is known to overwrite x[strlen (x)], adjust the last memcpy to | |
1051 | just memcpy (x, y, strlen (y)). SI must be the zero length | |
1052 | strinfo. */ | |
1053 | ||
1054 | static void | |
526ceb68 | 1055 | adjust_last_stmt (strinfo *si, gimple *stmt, bool is_strcat) |
8b57bfeb JJ |
1056 | { |
1057 | tree vuse, callee, len; | |
1058 | struct laststmt_struct last = laststmt; | |
526ceb68 | 1059 | strinfo *lastsi, *firstsi; |
f5fc4a04 | 1060 | unsigned len_arg_no = 2; |
8b57bfeb JJ |
1061 | |
1062 | laststmt.stmt = NULL; | |
1063 | laststmt.len = NULL_TREE; | |
1064 | laststmt.stridx = 0; | |
1065 | ||
1066 | if (last.stmt == NULL) | |
1067 | return; | |
1068 | ||
1069 | vuse = gimple_vuse (stmt); | |
1070 | if (vuse == NULL_TREE | |
1071 | || SSA_NAME_DEF_STMT (vuse) != last.stmt | |
1072 | || !has_single_use (vuse)) | |
1073 | return; | |
1074 | ||
1075 | gcc_assert (last.stridx > 0); | |
1076 | lastsi = get_strinfo (last.stridx); | |
1077 | if (lastsi == NULL) | |
1078 | return; | |
1079 | ||
1080 | if (lastsi != si) | |
1081 | { | |
1082 | if (lastsi->first == 0 || lastsi->first != si->first) | |
1083 | return; | |
1084 | ||
1085 | firstsi = verify_related_strinfos (si); | |
1086 | if (firstsi == NULL) | |
1087 | return; | |
1088 | while (firstsi != lastsi) | |
1089 | { | |
bde63fde RS |
1090 | firstsi = get_next_strinfo (firstsi); |
1091 | if (firstsi == NULL) | |
8b57bfeb | 1092 | return; |
8b57bfeb JJ |
1093 | } |
1094 | } | |
1095 | ||
e3f9a279 RS |
1096 | if (!is_strcat && !zero_length_string_p (si)) |
1097 | return; | |
8b57bfeb JJ |
1098 | |
1099 | if (is_gimple_assign (last.stmt)) | |
1100 | { | |
1101 | gimple_stmt_iterator gsi; | |
1102 | ||
1103 | if (!integer_zerop (gimple_assign_rhs1 (last.stmt))) | |
1104 | return; | |
1105 | if (stmt_could_throw_p (last.stmt)) | |
1106 | return; | |
1107 | gsi = gsi_for_stmt (last.stmt); | |
1108 | unlink_stmt_vdef (last.stmt); | |
1109 | release_defs (last.stmt); | |
1110 | gsi_remove (&gsi, true); | |
1111 | return; | |
1112 | } | |
1113 | ||
0ad84f34 | 1114 | if (!valid_builtin_call (last.stmt)) |
8b57bfeb JJ |
1115 | return; |
1116 | ||
3626621a | 1117 | callee = gimple_call_fndecl (last.stmt); |
8b57bfeb JJ |
1118 | switch (DECL_FUNCTION_CODE (callee)) |
1119 | { | |
1120 | case BUILT_IN_MEMCPY: | |
1121 | case BUILT_IN_MEMCPY_CHK: | |
1122 | break; | |
f5fc4a04 IE |
1123 | case BUILT_IN_MEMCPY_CHKP: |
1124 | case BUILT_IN_MEMCPY_CHK_CHKP: | |
1125 | len_arg_no = 4; | |
1126 | break; | |
8b57bfeb JJ |
1127 | default: |
1128 | return; | |
1129 | } | |
1130 | ||
f5fc4a04 | 1131 | len = gimple_call_arg (last.stmt, len_arg_no); |
cc269bb6 | 1132 | if (tree_fits_uhwi_p (len)) |
8b57bfeb | 1133 | { |
cc269bb6 | 1134 | if (!tree_fits_uhwi_p (last.len) |
8b57bfeb | 1135 | || integer_zerop (len) |
7d362f6c | 1136 | || tree_to_uhwi (len) != tree_to_uhwi (last.len) + 1) |
8b57bfeb JJ |
1137 | return; |
1138 | /* Don't adjust the length if it is divisible by 4, it is more efficient | |
1139 | to store the extra '\0' in that case. */ | |
7d362f6c | 1140 | if ((tree_to_uhwi (len) & 3) == 0) |
8b57bfeb JJ |
1141 | return; |
1142 | } | |
1143 | else if (TREE_CODE (len) == SSA_NAME) | |
1144 | { | |
355fe088 | 1145 | gimple *def_stmt = SSA_NAME_DEF_STMT (len); |
8b57bfeb JJ |
1146 | if (!is_gimple_assign (def_stmt) |
1147 | || gimple_assign_rhs_code (def_stmt) != PLUS_EXPR | |
1148 | || gimple_assign_rhs1 (def_stmt) != last.len | |
1149 | || !integer_onep (gimple_assign_rhs2 (def_stmt))) | |
1150 | return; | |
1151 | } | |
1152 | else | |
1153 | return; | |
1154 | ||
f5fc4a04 | 1155 | gimple_call_set_arg (last.stmt, len_arg_no, last.len); |
8b57bfeb JJ |
1156 | update_stmt (last.stmt); |
1157 | } | |
1158 | ||
06199618 MS |
1159 | /* For an LHS that is an SSA_NAME and for strlen() argument SRC, set |
1160 | LHS range info to [0, N] if SRC refers to a character array A[N] | |
1161 | with unknown length bounded by N. */ | |
1162 | ||
1163 | static void | |
1164 | maybe_set_strlen_range (tree lhs, tree src) | |
1165 | { | |
1166 | if (TREE_CODE (lhs) != SSA_NAME) | |
1167 | return; | |
1168 | ||
1169 | if (TREE_CODE (src) == SSA_NAME) | |
1170 | { | |
1171 | gimple *def = SSA_NAME_DEF_STMT (src); | |
1172 | if (is_gimple_assign (def) | |
1173 | && gimple_assign_rhs_code (def) == ADDR_EXPR) | |
1174 | src = gimple_assign_rhs1 (def); | |
1175 | } | |
1176 | ||
1177 | if (TREE_CODE (src) != ADDR_EXPR) | |
1178 | return; | |
1179 | ||
1180 | /* The last array member of a struct can be bigger than its size | |
1181 | suggests if it's treated as a poor-man's flexible array member. */ | |
1182 | src = TREE_OPERAND (src, 0); | |
1183 | if (TREE_CODE (TREE_TYPE (src)) != ARRAY_TYPE | |
1184 | || array_at_struct_end_p (src)) | |
1185 | return; | |
1186 | ||
1187 | tree type = TREE_TYPE (src); | |
1188 | if (tree dom = TYPE_DOMAIN (type)) | |
1189 | if (tree maxval = TYPE_MAX_VALUE (dom)) | |
1190 | { | |
1191 | wide_int max = wi::to_wide (maxval); | |
1192 | wide_int min = wi::zero (max.get_precision ()); | |
1193 | set_range_info (lhs, VR_RANGE, min, max); | |
1194 | } | |
1195 | } | |
1196 | ||
8b57bfeb JJ |
1197 | /* Handle a strlen call. If strlen of the argument is known, replace |
1198 | the strlen call with the known value, otherwise remember that strlen | |
1199 | of the argument is stored in the lhs SSA_NAME. */ | |
1200 | ||
1201 | static void | |
1202 | handle_builtin_strlen (gimple_stmt_iterator *gsi) | |
1203 | { | |
1204 | int idx; | |
1205 | tree src; | |
355fe088 | 1206 | gimple *stmt = gsi_stmt (*gsi); |
8b57bfeb JJ |
1207 | tree lhs = gimple_call_lhs (stmt); |
1208 | ||
1209 | if (lhs == NULL_TREE) | |
1210 | return; | |
1211 | ||
1212 | src = gimple_call_arg (stmt, 0); | |
1213 | idx = get_stridx (src); | |
1214 | if (idx) | |
1215 | { | |
526ceb68 | 1216 | strinfo *si = NULL; |
8b57bfeb JJ |
1217 | tree rhs; |
1218 | ||
1219 | if (idx < 0) | |
1220 | rhs = build_int_cst (TREE_TYPE (lhs), ~idx); | |
1221 | else | |
1222 | { | |
1223 | rhs = NULL_TREE; | |
1224 | si = get_strinfo (idx); | |
1225 | if (si != NULL) | |
1226 | rhs = get_string_length (si); | |
1227 | } | |
1228 | if (rhs != NULL_TREE) | |
1229 | { | |
1230 | if (dump_file && (dump_flags & TDF_DETAILS) != 0) | |
1231 | { | |
1232 | fprintf (dump_file, "Optimizing: "); | |
1233 | print_gimple_stmt (dump_file, stmt, 0, TDF_SLIM); | |
1234 | } | |
1235 | rhs = unshare_expr (rhs); | |
1236 | if (!useless_type_conversion_p (TREE_TYPE (lhs), TREE_TYPE (rhs))) | |
1237 | rhs = fold_convert_loc (gimple_location (stmt), | |
1238 | TREE_TYPE (lhs), rhs); | |
1239 | if (!update_call_from_tree (gsi, rhs)) | |
1240 | gimplify_and_update_call_from_tree (gsi, rhs); | |
1241 | stmt = gsi_stmt (*gsi); | |
1242 | update_stmt (stmt); | |
1243 | if (dump_file && (dump_flags & TDF_DETAILS) != 0) | |
1244 | { | |
1245 | fprintf (dump_file, "into: "); | |
1246 | print_gimple_stmt (dump_file, stmt, 0, TDF_SLIM); | |
1247 | } | |
1248 | if (si != NULL | |
e3f9a279 RS |
1249 | && TREE_CODE (si->nonzero_chars) != SSA_NAME |
1250 | && TREE_CODE (si->nonzero_chars) != INTEGER_CST | |
8b57bfeb JJ |
1251 | && !SSA_NAME_OCCURS_IN_ABNORMAL_PHI (lhs)) |
1252 | { | |
1253 | si = unshare_strinfo (si); | |
e3f9a279 RS |
1254 | si->nonzero_chars = lhs; |
1255 | gcc_assert (si->full_string_p); | |
8b57bfeb | 1256 | } |
025d57f0 | 1257 | |
6a33d0ff MS |
1258 | if (strlen_to_stridx) |
1259 | { | |
1260 | location_t loc = gimple_location (stmt); | |
1261 | strlen_to_stridx->put (lhs, stridx_strlenloc (idx, loc)); | |
1262 | } | |
8b57bfeb JJ |
1263 | return; |
1264 | } | |
1265 | } | |
1266 | if (SSA_NAME_OCCURS_IN_ABNORMAL_PHI (lhs)) | |
1267 | return; | |
1268 | if (idx == 0) | |
1269 | idx = new_stridx (src); | |
e3f9a279 RS |
1270 | else |
1271 | { | |
1272 | strinfo *si = get_strinfo (idx); | |
1273 | if (si != NULL) | |
1274 | { | |
1275 | if (!si->full_string_p && !si->stmt) | |
1276 | { | |
1277 | /* Until now we only had a lower bound on the string length. | |
1278 | Install LHS as the actual length. */ | |
1279 | si = unshare_strinfo (si); | |
1aad7106 | 1280 | tree old = si->nonzero_chars; |
e3f9a279 RS |
1281 | si->nonzero_chars = lhs; |
1282 | si->full_string_p = true; | |
1aad7106 RS |
1283 | if (TREE_CODE (old) == INTEGER_CST) |
1284 | { | |
1285 | location_t loc = gimple_location (stmt); | |
1286 | old = fold_convert_loc (loc, TREE_TYPE (lhs), old); | |
1287 | tree adj = fold_build2_loc (loc, MINUS_EXPR, | |
1288 | TREE_TYPE (lhs), lhs, old); | |
1289 | adjust_related_strinfos (loc, si, adj); | |
1290 | } | |
1291 | else | |
1292 | { | |
1293 | si->first = 0; | |
1294 | si->prev = 0; | |
1295 | si->next = 0; | |
1296 | } | |
e3f9a279 RS |
1297 | } |
1298 | return; | |
1299 | } | |
1300 | } | |
8b57bfeb JJ |
1301 | if (idx) |
1302 | { | |
e3f9a279 | 1303 | strinfo *si = new_strinfo (src, idx, lhs, true); |
8b57bfeb JJ |
1304 | set_strinfo (idx, si); |
1305 | find_equal_ptrs (src, idx); | |
025d57f0 | 1306 | |
06199618 MS |
1307 | /* For SRC that is an array of N elements, set LHS's range |
1308 | to [0, N]. */ | |
1309 | maybe_set_strlen_range (lhs, src); | |
1310 | ||
6a33d0ff MS |
1311 | if (strlen_to_stridx) |
1312 | { | |
1313 | location_t loc = gimple_location (stmt); | |
1314 | strlen_to_stridx->put (lhs, stridx_strlenloc (idx, loc)); | |
1315 | } | |
8b57bfeb JJ |
1316 | } |
1317 | } | |
1318 | ||
1319 | /* Handle a strchr call. If strlen of the first argument is known, replace | |
1320 | the strchr (x, 0) call with the endptr or x + strlen, otherwise remember | |
1321 | that lhs of the call is endptr and strlen of the argument is endptr - x. */ | |
1322 | ||
1323 | static void | |
1324 | handle_builtin_strchr (gimple_stmt_iterator *gsi) | |
1325 | { | |
1326 | int idx; | |
1327 | tree src; | |
355fe088 | 1328 | gimple *stmt = gsi_stmt (*gsi); |
8b57bfeb | 1329 | tree lhs = gimple_call_lhs (stmt); |
f5fc4a04 | 1330 | bool with_bounds = gimple_call_with_bounds_p (stmt); |
8b57bfeb JJ |
1331 | |
1332 | if (lhs == NULL_TREE) | |
1333 | return; | |
1334 | ||
f5fc4a04 | 1335 | if (!integer_zerop (gimple_call_arg (stmt, with_bounds ? 2 : 1))) |
8b57bfeb JJ |
1336 | return; |
1337 | ||
1338 | src = gimple_call_arg (stmt, 0); | |
1339 | idx = get_stridx (src); | |
1340 | if (idx) | |
1341 | { | |
526ceb68 | 1342 | strinfo *si = NULL; |
8b57bfeb JJ |
1343 | tree rhs; |
1344 | ||
1345 | if (idx < 0) | |
1346 | rhs = build_int_cst (size_type_node, ~idx); | |
1347 | else | |
1348 | { | |
1349 | rhs = NULL_TREE; | |
1350 | si = get_strinfo (idx); | |
1351 | if (si != NULL) | |
1352 | rhs = get_string_length (si); | |
1353 | } | |
1354 | if (rhs != NULL_TREE) | |
1355 | { | |
1356 | location_t loc = gimple_location (stmt); | |
1357 | ||
1358 | if (dump_file && (dump_flags & TDF_DETAILS) != 0) | |
1359 | { | |
1360 | fprintf (dump_file, "Optimizing: "); | |
1361 | print_gimple_stmt (dump_file, stmt, 0, TDF_SLIM); | |
1362 | } | |
1363 | if (si != NULL && si->endptr != NULL_TREE) | |
1364 | { | |
1365 | rhs = unshare_expr (si->endptr); | |
1366 | if (!useless_type_conversion_p (TREE_TYPE (lhs), | |
1367 | TREE_TYPE (rhs))) | |
1368 | rhs = fold_convert_loc (loc, TREE_TYPE (lhs), rhs); | |
1369 | } | |
1370 | else | |
1371 | { | |
1372 | rhs = fold_convert_loc (loc, sizetype, unshare_expr (rhs)); | |
1373 | rhs = fold_build2_loc (loc, POINTER_PLUS_EXPR, | |
1374 | TREE_TYPE (src), src, rhs); | |
1375 | if (!useless_type_conversion_p (TREE_TYPE (lhs), | |
1376 | TREE_TYPE (rhs))) | |
1377 | rhs = fold_convert_loc (loc, TREE_TYPE (lhs), rhs); | |
1378 | } | |
1379 | if (!update_call_from_tree (gsi, rhs)) | |
1380 | gimplify_and_update_call_from_tree (gsi, rhs); | |
1381 | stmt = gsi_stmt (*gsi); | |
1382 | update_stmt (stmt); | |
1383 | if (dump_file && (dump_flags & TDF_DETAILS) != 0) | |
1384 | { | |
1385 | fprintf (dump_file, "into: "); | |
1386 | print_gimple_stmt (dump_file, stmt, 0, TDF_SLIM); | |
1387 | } | |
1388 | if (si != NULL | |
1389 | && si->endptr == NULL_TREE | |
1390 | && !SSA_NAME_OCCURS_IN_ABNORMAL_PHI (lhs)) | |
1391 | { | |
1392 | si = unshare_strinfo (si); | |
1393 | si->endptr = lhs; | |
1394 | } | |
1395 | zero_length_string (lhs, si); | |
1396 | return; | |
1397 | } | |
1398 | } | |
1399 | if (SSA_NAME_OCCURS_IN_ABNORMAL_PHI (lhs)) | |
1400 | return; | |
1401 | if (TREE_CODE (src) != SSA_NAME || !SSA_NAME_OCCURS_IN_ABNORMAL_PHI (src)) | |
1402 | { | |
1403 | if (idx == 0) | |
1404 | idx = new_stridx (src); | |
1405 | else if (get_strinfo (idx) != NULL) | |
1406 | { | |
1407 | zero_length_string (lhs, NULL); | |
1408 | return; | |
1409 | } | |
1410 | if (idx) | |
1411 | { | |
1412 | location_t loc = gimple_location (stmt); | |
1413 | tree lhsu = fold_convert_loc (loc, size_type_node, lhs); | |
1414 | tree srcu = fold_convert_loc (loc, size_type_node, src); | |
1415 | tree length = fold_build2_loc (loc, MINUS_EXPR, | |
1416 | size_type_node, lhsu, srcu); | |
e3f9a279 | 1417 | strinfo *si = new_strinfo (src, idx, length, true); |
8b57bfeb JJ |
1418 | si->endptr = lhs; |
1419 | set_strinfo (idx, si); | |
1420 | find_equal_ptrs (src, idx); | |
1421 | zero_length_string (lhs, si); | |
1422 | } | |
1423 | } | |
1424 | else | |
1425 | zero_length_string (lhs, NULL); | |
1426 | } | |
1427 | ||
1428 | /* Handle a strcpy-like ({st{r,p}cpy,__st{r,p}cpy_chk}) call. | |
1429 | If strlen of the second argument is known, strlen of the first argument | |
1430 | is the same after this call. Furthermore, attempt to convert it to | |
1431 | memcpy. */ | |
1432 | ||
1433 | static void | |
1434 | handle_builtin_strcpy (enum built_in_function bcode, gimple_stmt_iterator *gsi) | |
1435 | { | |
1436 | int idx, didx; | |
cc8bea0a | 1437 | tree src, dst, srclen, len, lhs, type, fn, oldlen; |
8b57bfeb | 1438 | bool success; |
355fe088 | 1439 | gimple *stmt = gsi_stmt (*gsi); |
526ceb68 | 1440 | strinfo *si, *dsi, *olddsi, *zsi; |
8b57bfeb | 1441 | location_t loc; |
f5fc4a04 | 1442 | bool with_bounds = gimple_call_with_bounds_p (stmt); |
8b57bfeb | 1443 | |
f5fc4a04 | 1444 | src = gimple_call_arg (stmt, with_bounds ? 2 : 1); |
8b57bfeb JJ |
1445 | dst = gimple_call_arg (stmt, 0); |
1446 | lhs = gimple_call_lhs (stmt); | |
1447 | idx = get_stridx (src); | |
1448 | si = NULL; | |
1449 | if (idx > 0) | |
1450 | si = get_strinfo (idx); | |
1451 | ||
1452 | didx = get_stridx (dst); | |
1453 | olddsi = NULL; | |
1454 | oldlen = NULL_TREE; | |
1455 | if (didx > 0) | |
1456 | olddsi = get_strinfo (didx); | |
1457 | else if (didx < 0) | |
1458 | return; | |
1459 | ||
1460 | if (olddsi != NULL) | |
1461 | adjust_last_stmt (olddsi, stmt, false); | |
1462 | ||
1463 | srclen = NULL_TREE; | |
1464 | if (si != NULL) | |
1465 | srclen = get_string_length (si); | |
1466 | else if (idx < 0) | |
1467 | srclen = build_int_cst (size_type_node, ~idx); | |
1468 | ||
1469 | loc = gimple_location (stmt); | |
1470 | if (srclen == NULL_TREE) | |
1471 | switch (bcode) | |
1472 | { | |
1473 | case BUILT_IN_STRCPY: | |
1474 | case BUILT_IN_STRCPY_CHK: | |
f5fc4a04 IE |
1475 | case BUILT_IN_STRCPY_CHKP: |
1476 | case BUILT_IN_STRCPY_CHK_CHKP: | |
e79983f4 | 1477 | if (lhs != NULL_TREE || !builtin_decl_implicit_p (BUILT_IN_STPCPY)) |
8b57bfeb JJ |
1478 | return; |
1479 | break; | |
1480 | case BUILT_IN_STPCPY: | |
1481 | case BUILT_IN_STPCPY_CHK: | |
f5fc4a04 IE |
1482 | case BUILT_IN_STPCPY_CHKP: |
1483 | case BUILT_IN_STPCPY_CHK_CHKP: | |
8b57bfeb JJ |
1484 | if (lhs == NULL_TREE) |
1485 | return; | |
1486 | else | |
1487 | { | |
1488 | tree lhsuint = fold_convert_loc (loc, size_type_node, lhs); | |
1489 | srclen = fold_convert_loc (loc, size_type_node, dst); | |
1490 | srclen = fold_build2_loc (loc, MINUS_EXPR, size_type_node, | |
1491 | lhsuint, srclen); | |
1492 | } | |
1493 | break; | |
1494 | default: | |
1495 | gcc_unreachable (); | |
1496 | } | |
1497 | ||
1498 | if (didx == 0) | |
1499 | { | |
1500 | didx = new_stridx (dst); | |
1501 | if (didx == 0) | |
1502 | return; | |
1503 | } | |
1504 | if (olddsi != NULL) | |
1505 | { | |
e3f9a279 | 1506 | oldlen = olddsi->nonzero_chars; |
8b57bfeb | 1507 | dsi = unshare_strinfo (olddsi); |
e3f9a279 RS |
1508 | dsi->nonzero_chars = srclen; |
1509 | dsi->full_string_p = (srclen != NULL_TREE); | |
8b57bfeb JJ |
1510 | /* Break the chain, so adjust_related_strinfo on later pointers in |
1511 | the chain won't adjust this one anymore. */ | |
1512 | dsi->next = 0; | |
1513 | dsi->stmt = NULL; | |
1514 | dsi->endptr = NULL_TREE; | |
1515 | } | |
1516 | else | |
1517 | { | |
e3f9a279 | 1518 | dsi = new_strinfo (dst, didx, srclen, srclen != NULL_TREE); |
8b57bfeb JJ |
1519 | set_strinfo (didx, dsi); |
1520 | find_equal_ptrs (dst, didx); | |
1521 | } | |
1522 | dsi->writable = true; | |
1523 | dsi->dont_invalidate = true; | |
1524 | ||
e3f9a279 | 1525 | if (dsi->nonzero_chars == NULL_TREE) |
8b57bfeb | 1526 | { |
526ceb68 | 1527 | strinfo *chainsi; |
93a90db6 | 1528 | |
8b57bfeb JJ |
1529 | /* If string length of src is unknown, use delayed length |
1530 | computation. If string lenth of dst will be needed, it | |
1531 | can be computed by transforming this strcpy call into | |
1532 | stpcpy and subtracting dst from the return value. */ | |
93a90db6 AK |
1533 | |
1534 | /* Look for earlier strings whose length could be determined if | |
1535 | this strcpy is turned into an stpcpy. */ | |
1536 | ||
1537 | if (dsi->prev != 0 && (chainsi = verify_related_strinfos (dsi)) != NULL) | |
1538 | { | |
1539 | for (; chainsi && chainsi != dsi; chainsi = get_strinfo (chainsi->next)) | |
1540 | { | |
1541 | /* When setting a stmt for delayed length computation | |
1542 | prevent all strinfos through dsi from being | |
1543 | invalidated. */ | |
1544 | chainsi = unshare_strinfo (chainsi); | |
1545 | chainsi->stmt = stmt; | |
e3f9a279 RS |
1546 | chainsi->nonzero_chars = NULL_TREE; |
1547 | chainsi->full_string_p = false; | |
93a90db6 AK |
1548 | chainsi->endptr = NULL_TREE; |
1549 | chainsi->dont_invalidate = true; | |
1550 | } | |
1551 | } | |
8b57bfeb | 1552 | dsi->stmt = stmt; |
cc8bea0a MS |
1553 | |
1554 | /* Try to detect overlap before returning. This catches cases | |
1555 | like strcpy (d, d + n) where n is non-constant whose range | |
1556 | is such that (n <= strlen (d) holds). | |
1557 | ||
1558 | OLDDSI->NONZERO_chars may have been reset by this point with | |
1559 | oldlen holding it original value. */ | |
1560 | if (olddsi && oldlen) | |
1561 | { | |
1562 | /* Add 1 for the terminating NUL. */ | |
1563 | tree type = TREE_TYPE (oldlen); | |
1564 | oldlen = fold_build2 (PLUS_EXPR, type, oldlen, | |
1565 | build_int_cst (type, 1)); | |
1566 | check_bounds_or_overlap (as_a <gcall *>(stmt), olddsi->ptr, src, | |
1567 | oldlen, NULL_TREE); | |
1568 | } | |
1569 | ||
8b57bfeb JJ |
1570 | return; |
1571 | } | |
1572 | ||
1573 | if (olddsi != NULL) | |
1574 | { | |
1575 | tree adj = NULL_TREE; | |
1576 | if (oldlen == NULL_TREE) | |
1577 | ; | |
1578 | else if (integer_zerop (oldlen)) | |
1579 | adj = srclen; | |
1580 | else if (TREE_CODE (oldlen) == INTEGER_CST | |
1581 | || TREE_CODE (srclen) == INTEGER_CST) | |
1582 | adj = fold_build2_loc (loc, MINUS_EXPR, | |
1583 | TREE_TYPE (srclen), srclen, | |
1584 | fold_convert_loc (loc, TREE_TYPE (srclen), | |
1585 | oldlen)); | |
1586 | if (adj != NULL_TREE) | |
1587 | adjust_related_strinfos (loc, dsi, adj); | |
1588 | else | |
1589 | dsi->prev = 0; | |
1590 | } | |
1591 | /* strcpy src may not overlap dst, so src doesn't need to be | |
1592 | invalidated either. */ | |
1593 | if (si != NULL) | |
1594 | si->dont_invalidate = true; | |
1595 | ||
1596 | fn = NULL_TREE; | |
1597 | zsi = NULL; | |
1598 | switch (bcode) | |
1599 | { | |
1600 | case BUILT_IN_STRCPY: | |
f5fc4a04 | 1601 | case BUILT_IN_STRCPY_CHKP: |
e79983f4 | 1602 | fn = builtin_decl_implicit (BUILT_IN_MEMCPY); |
8b57bfeb | 1603 | if (lhs) |
9771b263 | 1604 | ssa_ver_to_stridx[SSA_NAME_VERSION (lhs)] = didx; |
8b57bfeb JJ |
1605 | break; |
1606 | case BUILT_IN_STRCPY_CHK: | |
f5fc4a04 | 1607 | case BUILT_IN_STRCPY_CHK_CHKP: |
e79983f4 | 1608 | fn = builtin_decl_explicit (BUILT_IN_MEMCPY_CHK); |
8b57bfeb | 1609 | if (lhs) |
9771b263 | 1610 | ssa_ver_to_stridx[SSA_NAME_VERSION (lhs)] = didx; |
8b57bfeb JJ |
1611 | break; |
1612 | case BUILT_IN_STPCPY: | |
f5fc4a04 | 1613 | case BUILT_IN_STPCPY_CHKP: |
8b57bfeb JJ |
1614 | /* This would need adjustment of the lhs (subtract one), |
1615 | or detection that the trailing '\0' doesn't need to be | |
1616 | written, if it will be immediately overwritten. | |
e79983f4 | 1617 | fn = builtin_decl_explicit (BUILT_IN_MEMPCPY); */ |
8b57bfeb JJ |
1618 | if (lhs) |
1619 | { | |
1620 | dsi->endptr = lhs; | |
1621 | zsi = zero_length_string (lhs, dsi); | |
1622 | } | |
1623 | break; | |
1624 | case BUILT_IN_STPCPY_CHK: | |
f5fc4a04 | 1625 | case BUILT_IN_STPCPY_CHK_CHKP: |
8b57bfeb JJ |
1626 | /* This would need adjustment of the lhs (subtract one), |
1627 | or detection that the trailing '\0' doesn't need to be | |
1628 | written, if it will be immediately overwritten. | |
e79983f4 | 1629 | fn = builtin_decl_explicit (BUILT_IN_MEMPCPY_CHK); */ |
8b57bfeb JJ |
1630 | if (lhs) |
1631 | { | |
1632 | dsi->endptr = lhs; | |
1633 | zsi = zero_length_string (lhs, dsi); | |
1634 | } | |
1635 | break; | |
1636 | default: | |
1637 | gcc_unreachable (); | |
1638 | } | |
1639 | if (zsi != NULL) | |
1640 | zsi->dont_invalidate = true; | |
1641 | ||
cc8bea0a MS |
1642 | if (fn) |
1643 | { | |
1644 | tree args = TYPE_ARG_TYPES (TREE_TYPE (fn)); | |
1645 | type = TREE_VALUE (TREE_CHAIN (TREE_CHAIN (args))); | |
1646 | } | |
1647 | else | |
1648 | type = size_type_node; | |
8b57bfeb JJ |
1649 | |
1650 | len = fold_convert_loc (loc, type, unshare_expr (srclen)); | |
1651 | len = fold_build2_loc (loc, PLUS_EXPR, type, len, build_int_cst (type, 1)); | |
cc8bea0a MS |
1652 | |
1653 | /* Set the no-warning bit on the transformed statement? */ | |
1654 | bool set_no_warning = false; | |
1655 | ||
1656 | if (const strinfo *chksi = olddsi ? olddsi : dsi) | |
1657 | if (si | |
1658 | && !check_bounds_or_overlap (as_a <gcall *>(stmt), chksi->ptr, si->ptr, | |
1659 | NULL_TREE, len)) | |
1660 | { | |
1661 | gimple_set_no_warning (stmt, true); | |
1662 | set_no_warning = true; | |
1663 | } | |
1664 | ||
1665 | if (fn == NULL_TREE) | |
1666 | return; | |
1667 | ||
8b57bfeb JJ |
1668 | len = force_gimple_operand_gsi (gsi, len, true, NULL_TREE, true, |
1669 | GSI_SAME_STMT); | |
1670 | if (dump_file && (dump_flags & TDF_DETAILS) != 0) | |
1671 | { | |
1672 | fprintf (dump_file, "Optimizing: "); | |
1673 | print_gimple_stmt (dump_file, stmt, 0, TDF_SLIM); | |
1674 | } | |
f5fc4a04 IE |
1675 | if (with_bounds) |
1676 | { | |
1677 | fn = chkp_maybe_create_clone (fn)->decl; | |
1678 | if (gimple_call_num_args (stmt) == 4) | |
1679 | success = update_gimple_call (gsi, fn, 5, dst, | |
1680 | gimple_call_arg (stmt, 1), | |
1681 | src, | |
1682 | gimple_call_arg (stmt, 3), | |
1683 | len); | |
1684 | else | |
1685 | success = update_gimple_call (gsi, fn, 6, dst, | |
1686 | gimple_call_arg (stmt, 1), | |
1687 | src, | |
1688 | gimple_call_arg (stmt, 3), | |
1689 | len, | |
1690 | gimple_call_arg (stmt, 4)); | |
1691 | } | |
8b57bfeb | 1692 | else |
f5fc4a04 IE |
1693 | if (gimple_call_num_args (stmt) == 2) |
1694 | success = update_gimple_call (gsi, fn, 3, dst, src, len); | |
1695 | else | |
1696 | success = update_gimple_call (gsi, fn, 4, dst, src, len, | |
1697 | gimple_call_arg (stmt, 2)); | |
8b57bfeb JJ |
1698 | if (success) |
1699 | { | |
1700 | stmt = gsi_stmt (*gsi); | |
f5fc4a04 | 1701 | gimple_call_set_with_bounds (stmt, with_bounds); |
8b57bfeb JJ |
1702 | update_stmt (stmt); |
1703 | if (dump_file && (dump_flags & TDF_DETAILS) != 0) | |
1704 | { | |
1705 | fprintf (dump_file, "into: "); | |
1706 | print_gimple_stmt (dump_file, stmt, 0, TDF_SLIM); | |
1707 | } | |
1708 | /* Allow adjust_last_stmt to decrease this memcpy's size. */ | |
1709 | laststmt.stmt = stmt; | |
1710 | laststmt.len = srclen; | |
1711 | laststmt.stridx = dsi->idx; | |
1712 | } | |
1713 | else if (dump_file && (dump_flags & TDF_DETAILS) != 0) | |
1714 | fprintf (dump_file, "not possible.\n"); | |
cc8bea0a MS |
1715 | |
1716 | if (set_no_warning) | |
1717 | gimple_set_no_warning (stmt, true); | |
1718 | } | |
1719 | ||
1720 | /* Check the size argument to the built-in forms of stpncpy and strncpy | |
1721 | for out-of-bounds offsets or overlapping access, and to see if the | |
1722 | size argument is derived from a call to strlen() on the source argument, | |
1723 | and if so, issue an appropriate warning. */ | |
1724 | ||
1725 | static void | |
1726 | handle_builtin_strncat (built_in_function bcode, gimple_stmt_iterator *gsi) | |
1727 | { | |
1728 | /* Same as stxncpy(). */ | |
1729 | handle_builtin_stxncpy (bcode, gsi); | |
8b57bfeb JJ |
1730 | } |
1731 | ||
025d57f0 MS |
1732 | /* Return true if LEN depends on a call to strlen(SRC) in an interesting |
1733 | way. LEN can either be an integer expression, or a pointer (to char). | |
1734 | When it is the latter (such as in recursive calls to self) is is | |
1735 | assumed to be the argument in some call to strlen() whose relationship | |
1736 | to SRC is being ascertained. */ | |
1737 | ||
1738 | static bool | |
1739 | is_strlen_related_p (tree src, tree len) | |
1740 | { | |
1741 | if (TREE_CODE (TREE_TYPE (len)) == POINTER_TYPE | |
1742 | && operand_equal_p (src, len, 0)) | |
1743 | return true; | |
1744 | ||
1745 | if (TREE_CODE (len) != SSA_NAME) | |
1746 | return false; | |
1747 | ||
1748 | gimple *def_stmt = SSA_NAME_DEF_STMT (len); | |
1749 | if (!def_stmt) | |
1750 | return false; | |
1751 | ||
1752 | if (is_gimple_call (def_stmt)) | |
1753 | { | |
1754 | tree func = gimple_call_fndecl (def_stmt); | |
1755 | if (!valid_builtin_call (def_stmt) | |
1756 | || DECL_FUNCTION_CODE (func) != BUILT_IN_STRLEN) | |
1757 | return false; | |
1758 | ||
1759 | tree arg = gimple_call_arg (def_stmt, 0); | |
1760 | return is_strlen_related_p (src, arg); | |
1761 | } | |
1762 | ||
1763 | if (!is_gimple_assign (def_stmt)) | |
1764 | return false; | |
1765 | ||
1766 | tree_code code = gimple_assign_rhs_code (def_stmt); | |
1767 | tree rhs1 = gimple_assign_rhs1 (def_stmt); | |
1768 | tree rhstype = TREE_TYPE (rhs1); | |
1769 | ||
1770 | if ((TREE_CODE (rhstype) == POINTER_TYPE && code == POINTER_PLUS_EXPR) | |
1771 | || (INTEGRAL_TYPE_P (rhstype) | |
1772 | && (code == BIT_AND_EXPR | |
1773 | || code == NOP_EXPR))) | |
1774 | { | |
1775 | /* Pointer plus (an integer) and integer cast or truncation are | |
1776 | considered among the (potentially) related expressions to strlen. | |
1777 | Others are not. */ | |
1778 | return is_strlen_related_p (src, rhs1); | |
1779 | } | |
1780 | ||
1781 | return false; | |
1782 | } | |
1783 | ||
5d0d5d68 MS |
1784 | /* Called by handle_builtin_stxncpy and by gimple_fold_builtin_strncpy |
1785 | in gimple-fold.c. | |
1786 | Check to see if the specified bound is a) equal to the size of | |
1787 | the destination DST and if so, b) if it's immediately followed by | |
1788 | DST[CNT - 1] = '\0'. If a) holds and b) does not, warn. Otherwise, | |
1789 | do nothing. Return true if diagnostic has been issued. | |
025d57f0 MS |
1790 | |
1791 | The purpose is to diagnose calls to strncpy and stpncpy that do | |
1792 | not nul-terminate the copy while allowing for the idiom where | |
1793 | such a call is immediately followed by setting the last element | |
1794 | to nul, as in: | |
1795 | char a[32]; | |
1796 | strncpy (a, s, sizeof a); | |
1797 | a[sizeof a - 1] = '\0'; | |
1798 | */ | |
1799 | ||
5d0d5d68 | 1800 | bool |
025d57f0 MS |
1801 | maybe_diag_stxncpy_trunc (gimple_stmt_iterator gsi, tree src, tree cnt) |
1802 | { | |
025d57f0 | 1803 | gimple *stmt = gsi_stmt (gsi); |
e9b9fa4c MS |
1804 | if (gimple_no_warning_p (stmt)) |
1805 | return false; | |
025d57f0 MS |
1806 | |
1807 | wide_int cntrange[2]; | |
1808 | ||
1809 | if (TREE_CODE (cnt) == INTEGER_CST) | |
1810 | cntrange[0] = cntrange[1] = wi::to_wide (cnt); | |
1811 | else if (TREE_CODE (cnt) == SSA_NAME) | |
1812 | { | |
1813 | enum value_range_type rng = get_range_info (cnt, cntrange, cntrange + 1); | |
1814 | if (rng == VR_RANGE) | |
1815 | ; | |
1816 | else if (rng == VR_ANTI_RANGE) | |
1817 | { | |
1818 | wide_int maxobjsize = wi::to_wide (TYPE_MAX_VALUE (ptrdiff_type_node)); | |
1819 | ||
1820 | if (wi::ltu_p (cntrange[1], maxobjsize)) | |
1821 | { | |
1822 | cntrange[0] = cntrange[1] + 1; | |
1823 | cntrange[1] = maxobjsize; | |
1824 | } | |
1825 | else | |
1826 | { | |
1827 | cntrange[1] = cntrange[0] - 1; | |
1828 | cntrange[0] = wi::zero (TYPE_PRECISION (TREE_TYPE (cnt))); | |
1829 | } | |
1830 | } | |
1831 | else | |
1832 | return false; | |
1833 | } | |
1834 | else | |
1835 | return false; | |
1836 | ||
1837 | /* Negative value is the constant string length. If it's less than | |
5d0d5d68 MS |
1838 | the lower bound there is no truncation. Avoid calling get_stridx() |
1839 | when ssa_ver_to_stridx is empty. That implies the caller isn't | |
1840 | running under the control of this pass and ssa_ver_to_stridx hasn't | |
1841 | been created yet. */ | |
1842 | int sidx = ssa_ver_to_stridx.length () ? get_stridx (src) : 0; | |
025d57f0 MS |
1843 | if (sidx < 0 && wi::gtu_p (cntrange[0], ~sidx)) |
1844 | return false; | |
1845 | ||
1846 | tree dst = gimple_call_arg (stmt, 0); | |
025d57f0 MS |
1847 | tree dstdecl = dst; |
1848 | if (TREE_CODE (dstdecl) == ADDR_EXPR) | |
1849 | dstdecl = TREE_OPERAND (dstdecl, 0); | |
1850 | ||
6a33d0ff MS |
1851 | /* If the destination refers to a an array/pointer declared nonstring |
1852 | return early. */ | |
1853 | tree ref = NULL_TREE; | |
1854 | if (get_attr_nonstring_decl (dstdecl, &ref)) | |
1855 | return false; | |
025d57f0 MS |
1856 | |
1857 | /* Look for dst[i] = '\0'; after the stxncpy() call and if found | |
1858 | avoid the truncation warning. */ | |
b25e5572 | 1859 | gsi_next_nondebug (&gsi); |
025d57f0 | 1860 | gimple *next_stmt = gsi_stmt (gsi); |
a76acaed MS |
1861 | if (!next_stmt) |
1862 | { | |
1863 | /* When there is no statement in the same basic block check | |
1864 | the immediate successor block. */ | |
1865 | if (basic_block bb = gimple_bb (stmt)) | |
1866 | { | |
1867 | if (single_succ_p (bb)) | |
1868 | { | |
1869 | /* For simplicity, ignore blocks with multiple outgoing | |
1870 | edges for now and only consider successor blocks along | |
1871 | normal edges. */ | |
1872 | edge e = EDGE_SUCC (bb, 0); | |
1873 | if (!(e->flags & EDGE_ABNORMAL)) | |
1874 | { | |
1875 | gsi = gsi_start_bb (e->dest); | |
1876 | next_stmt = gsi_stmt (gsi); | |
1877 | if (next_stmt && is_gimple_debug (next_stmt)) | |
1878 | { | |
1879 | gsi_next_nondebug (&gsi); | |
1880 | next_stmt = gsi_stmt (gsi); | |
1881 | } | |
1882 | } | |
1883 | } | |
1884 | } | |
1885 | } | |
025d57f0 | 1886 | |
a76acaed | 1887 | if (next_stmt && is_gimple_assign (next_stmt)) |
025d57f0 | 1888 | { |
025d57f0 | 1889 | tree lhs = gimple_assign_lhs (next_stmt); |
6a33d0ff MS |
1890 | tree_code code = TREE_CODE (lhs); |
1891 | if (code == ARRAY_REF || code == MEM_REF) | |
1892 | lhs = TREE_OPERAND (lhs, 0); | |
1893 | ||
1894 | tree func = gimple_call_fndecl (stmt); | |
1895 | if (DECL_FUNCTION_CODE (func) == BUILT_IN_STPNCPY) | |
1896 | { | |
1897 | tree ret = gimple_call_lhs (stmt); | |
1898 | if (ret && operand_equal_p (ret, lhs, 0)) | |
1899 | return false; | |
1900 | } | |
1901 | ||
1902 | /* Determine the base address and offset of the reference, | |
1903 | ignoring the innermost array index. */ | |
1904 | if (TREE_CODE (ref) == ARRAY_REF) | |
1905 | ref = TREE_OPERAND (ref, 0); | |
1906 | ||
a90c8804 | 1907 | poly_int64 dstoff; |
6a33d0ff MS |
1908 | tree dstbase = get_addr_base_and_unit_offset (ref, &dstoff); |
1909 | ||
a90c8804 | 1910 | poly_int64 lhsoff; |
6a33d0ff MS |
1911 | tree lhsbase = get_addr_base_and_unit_offset (lhs, &lhsoff); |
1912 | if (lhsbase | |
44e60df3 | 1913 | && dstbase |
a90c8804 | 1914 | && known_eq (dstoff, lhsoff) |
6a33d0ff | 1915 | && operand_equal_p (dstbase, lhsbase, 0)) |
025d57f0 MS |
1916 | return false; |
1917 | } | |
1918 | ||
1919 | int prec = TYPE_PRECISION (TREE_TYPE (cnt)); | |
1920 | wide_int lenrange[2]; | |
1921 | if (strinfo *sisrc = sidx > 0 ? get_strinfo (sidx) : NULL) | |
1922 | { | |
1923 | lenrange[0] = (sisrc->nonzero_chars | |
1924 | && TREE_CODE (sisrc->nonzero_chars) == INTEGER_CST | |
1925 | ? wi::to_wide (sisrc->nonzero_chars) | |
1926 | : wi::zero (prec)); | |
1927 | lenrange[1] = lenrange[0]; | |
1928 | } | |
1929 | else if (sidx < 0) | |
1930 | lenrange[0] = lenrange[1] = wi::shwi (~sidx, prec); | |
1931 | else | |
1932 | { | |
1933 | tree range[2]; | |
1934 | get_range_strlen (src, range); | |
c6ba596b MP |
1935 | if (range[0] != NULL_TREE |
1936 | && TREE_CODE (range[0]) == INTEGER_CST | |
1937 | && range[1] != NULL_TREE | |
1938 | && TREE_CODE (range[1]) == INTEGER_CST) | |
025d57f0 MS |
1939 | { |
1940 | lenrange[0] = wi::to_wide (range[0], prec); | |
1941 | lenrange[1] = wi::to_wide (range[1], prec); | |
1942 | } | |
1943 | else | |
1944 | { | |
1945 | lenrange[0] = wi::shwi (0, prec); | |
1946 | lenrange[1] = wi::shwi (-1, prec); | |
1947 | } | |
1948 | } | |
1949 | ||
1950 | location_t callloc = gimple_location (stmt); | |
1951 | tree func = gimple_call_fndecl (stmt); | |
1952 | ||
1953 | if (lenrange[0] != 0 || !wi::neg_p (lenrange[1])) | |
1954 | { | |
1955 | /* If the longest source string is shorter than the lower bound | |
1956 | of the specified count the copy is definitely nul-terminated. */ | |
1957 | if (wi::ltu_p (lenrange[1], cntrange[0])) | |
1958 | return false; | |
1959 | ||
1960 | if (wi::neg_p (lenrange[1])) | |
1961 | { | |
1962 | /* The length of one of the strings is unknown but at least | |
1963 | one has non-zero length and that length is stored in | |
1964 | LENRANGE[1]. Swap the bounds to force a "may be truncated" | |
1965 | warning below. */ | |
1966 | lenrange[1] = lenrange[0]; | |
1967 | lenrange[0] = wi::shwi (0, prec); | |
1968 | } | |
1969 | ||
5d0d5d68 MS |
1970 | gcall *call = as_a <gcall *> (stmt); |
1971 | ||
1972 | if (lenrange[0] == cntrange[1] && cntrange[0] == cntrange[1]) | |
1c89478a MS |
1973 | return warning_n (callloc, OPT_Wstringop_truncation, |
1974 | cntrange[0].to_uhwi (), | |
1975 | "%G%qD output truncated before terminating " | |
1976 | "nul copying %E byte from a string of the " | |
1977 | "same length", | |
1978 | "%G%qD output truncated before terminating nul " | |
1979 | "copying %E bytes from a string of the same " | |
1980 | "length", | |
1981 | call, func, cnt); | |
5d0d5d68 | 1982 | else if (wi::geu_p (lenrange[0], cntrange[1])) |
025d57f0 MS |
1983 | { |
1984 | /* The shortest string is longer than the upper bound of | |
1985 | the count so the truncation is certain. */ | |
1986 | if (cntrange[0] == cntrange[1]) | |
1c89478a MS |
1987 | return warning_n (callloc, OPT_Wstringop_truncation, |
1988 | cntrange[0].to_uhwi (), | |
1989 | "%G%qD output truncated copying %E byte " | |
1990 | "from a string of length %wu", | |
1991 | "%G%qD output truncated copying %E bytes " | |
1992 | "from a string of length %wu", | |
1993 | call, func, cnt, lenrange[0].to_uhwi ()); | |
025d57f0 MS |
1994 | |
1995 | return warning_at (callloc, OPT_Wstringop_truncation, | |
5d0d5d68 | 1996 | "%G%qD output truncated copying between %wu " |
025d57f0 | 1997 | "and %wu bytes from a string of length %wu", |
5d0d5d68 | 1998 | call, func, cntrange[0].to_uhwi (), |
025d57f0 MS |
1999 | cntrange[1].to_uhwi (), lenrange[0].to_uhwi ()); |
2000 | } | |
2001 | else if (wi::geu_p (lenrange[1], cntrange[1])) | |
2002 | { | |
2003 | /* The longest string is longer than the upper bound of | |
2004 | the count so the truncation is possible. */ | |
2005 | if (cntrange[0] == cntrange[1]) | |
1c89478a MS |
2006 | return warning_n (callloc, OPT_Wstringop_truncation, |
2007 | cntrange[0].to_uhwi (), | |
2008 | "%G%qD output may be truncated copying %E " | |
2009 | "byte from a string of length %wu", | |
2010 | "%G%qD output may be truncated copying %E " | |
2011 | "bytes from a string of length %wu", | |
2012 | call, func, cnt, lenrange[1].to_uhwi ()); | |
025d57f0 MS |
2013 | |
2014 | return warning_at (callloc, OPT_Wstringop_truncation, | |
5d0d5d68 | 2015 | "%G%qD output may be truncated copying between %wu " |
025d57f0 | 2016 | "and %wu bytes from a string of length %wu", |
5d0d5d68 | 2017 | call, func, cntrange[0].to_uhwi (), |
025d57f0 MS |
2018 | cntrange[1].to_uhwi (), lenrange[1].to_uhwi ()); |
2019 | } | |
2020 | ||
2021 | if (cntrange[0] != cntrange[1] | |
2022 | && wi::leu_p (cntrange[0], lenrange[0]) | |
2023 | && wi::leu_p (cntrange[1], lenrange[0] + 1)) | |
2024 | { | |
2025 | /* If the source (including the terminating nul) is longer than | |
2026 | the lower bound of the specified count but shorter than the | |
2027 | upper bound the copy may (but need not) be truncated. */ | |
2028 | return warning_at (callloc, OPT_Wstringop_truncation, | |
5d0d5d68 MS |
2029 | "%G%qD output may be truncated copying between " |
2030 | "%wu and %wu bytes from a string of length %wu", | |
2031 | call, func, cntrange[0].to_uhwi (), | |
025d57f0 MS |
2032 | cntrange[1].to_uhwi (), lenrange[0].to_uhwi ()); |
2033 | } | |
2034 | } | |
2035 | ||
2036 | if (tree dstsize = compute_objsize (dst, 1)) | |
2037 | { | |
2038 | /* The source length is uknown. Try to determine the destination | |
2039 | size and see if it matches the specified bound. If not, bail. | |
2040 | Otherwise go on to see if it should be diagnosed for possible | |
2041 | truncation. */ | |
2042 | if (!dstsize) | |
2043 | return false; | |
2044 | ||
2045 | if (wi::to_wide (dstsize) != cntrange[1]) | |
2046 | return false; | |
2047 | ||
2048 | if (cntrange[0] == cntrange[1]) | |
2049 | return warning_at (callloc, OPT_Wstringop_truncation, | |
5d0d5d68 MS |
2050 | "%G%qD specified bound %E equals destination size", |
2051 | as_a <gcall *> (stmt), func, cnt); | |
025d57f0 MS |
2052 | } |
2053 | ||
2054 | return false; | |
2055 | } | |
2056 | ||
cc8bea0a MS |
2057 | /* Check the arguments to the built-in forms of stpncpy and strncpy for |
2058 | out-of-bounds offsets or overlapping access, and to see if the size | |
2059 | is derived from calling strlen() on the source argument, and if so, | |
2060 | issue the appropriate warning. */ | |
025d57f0 MS |
2061 | |
2062 | static void | |
2063 | handle_builtin_stxncpy (built_in_function, gimple_stmt_iterator *gsi) | |
2064 | { | |
6a33d0ff MS |
2065 | if (!strlen_to_stridx) |
2066 | return; | |
2067 | ||
025d57f0 MS |
2068 | gimple *stmt = gsi_stmt (*gsi); |
2069 | ||
2070 | bool with_bounds = gimple_call_with_bounds_p (stmt); | |
2071 | ||
cc8bea0a | 2072 | tree dst = gimple_call_arg (stmt, with_bounds ? 1 : 0); |
025d57f0 MS |
2073 | tree src = gimple_call_arg (stmt, with_bounds ? 2 : 1); |
2074 | tree len = gimple_call_arg (stmt, with_bounds ? 3 : 2); | |
cc8bea0a MS |
2075 | tree dstsize = NULL_TREE, srcsize = NULL_TREE; |
2076 | ||
2077 | int didx = get_stridx (dst); | |
2078 | if (strinfo *sidst = didx > 0 ? get_strinfo (didx) : NULL) | |
2079 | { | |
2080 | /* Compute the size of the destination string including the NUL. */ | |
2081 | if (sidst->nonzero_chars) | |
2082 | { | |
2083 | tree type = TREE_TYPE (sidst->nonzero_chars); | |
2084 | dstsize = fold_build2 (PLUS_EXPR, type, sidst->nonzero_chars, | |
2085 | build_int_cst (type, 1)); | |
2086 | } | |
2087 | dst = sidst->ptr; | |
2088 | } | |
2089 | ||
2090 | int sidx = get_stridx (src); | |
2091 | strinfo *sisrc = sidx > 0 ? get_strinfo (sidx) : NULL; | |
2092 | if (sisrc) | |
2093 | { | |
2094 | /* strncat() and strncpy() can modify the source string by writing | |
2095 | over the terminating nul so SISRC->DONT_INVALIDATE must be left | |
2096 | clear. */ | |
2097 | ||
2098 | /* Compute the size of the source string including the NUL. */ | |
2099 | if (sisrc->nonzero_chars) | |
2100 | { | |
2101 | tree type = TREE_TYPE (sisrc->nonzero_chars); | |
2102 | srcsize = fold_build2 (PLUS_EXPR, type, sisrc->nonzero_chars, | |
2103 | build_int_cst (type, 1)); | |
2104 | } | |
2105 | ||
2106 | src = sisrc->ptr; | |
2107 | } | |
2108 | else | |
2109 | srcsize = NULL_TREE; | |
2110 | ||
2111 | if (!check_bounds_or_overlap (as_a <gcall *>(stmt), dst, src, | |
2112 | dstsize, srcsize)) | |
2113 | { | |
2114 | gimple_set_no_warning (stmt, true); | |
2115 | return; | |
2116 | } | |
025d57f0 MS |
2117 | |
2118 | /* If the length argument was computed from strlen(S) for some string | |
2119 | S retrieve the strinfo index for the string (PSS->FIRST) alonng with | |
2120 | the location of the strlen() call (PSS->SECOND). */ | |
6a33d0ff | 2121 | stridx_strlenloc *pss = strlen_to_stridx->get (len); |
025d57f0 MS |
2122 | if (!pss || pss->first <= 0) |
2123 | { | |
2124 | if (maybe_diag_stxncpy_trunc (*gsi, src, len)) | |
2125 | gimple_set_no_warning (stmt, true); | |
2126 | ||
2127 | return; | |
2128 | } | |
2129 | ||
025d57f0 MS |
2130 | /* Retrieve the strinfo data for the string S that LEN was computed |
2131 | from as some function F of strlen (S) (i.e., LEN need not be equal | |
2132 | to strlen(S)). */ | |
2133 | strinfo *silen = get_strinfo (pss->first); | |
2134 | ||
2135 | location_t callloc = gimple_location (stmt); | |
2136 | ||
2137 | tree func = gimple_call_fndecl (stmt); | |
2138 | ||
2139 | bool warned = false; | |
2140 | ||
2141 | /* When -Wstringop-truncation is set, try to determine truncation | |
2142 | before diagnosing possible overflow. Truncation is implied by | |
2143 | the LEN argument being equal to strlen(SRC), regardless of | |
2144 | whether its value is known. Otherwise, issue the more generic | |
2145 | -Wstringop-overflow which triggers for LEN arguments that in | |
2146 | any meaningful way depend on strlen(SRC). */ | |
6a33d0ff MS |
2147 | if (sisrc == silen |
2148 | && is_strlen_related_p (src, len) | |
2149 | && warning_at (callloc, OPT_Wstringop_truncation, | |
5d0d5d68 | 2150 | "%G%qD output truncated before terminating nul " |
6a33d0ff | 2151 | "copying as many bytes from a string as its length", |
5d0d5d68 | 2152 | as_a <gcall *>(stmt), func)) |
6a33d0ff | 2153 | warned = true; |
025d57f0 MS |
2154 | else if (silen && is_strlen_related_p (src, silen->ptr)) |
2155 | warned = warning_at (callloc, OPT_Wstringop_overflow_, | |
5d0d5d68 MS |
2156 | "%G%qD specified bound depends on the length " |
2157 | "of the source argument", | |
2158 | as_a <gcall *>(stmt), func); | |
025d57f0 MS |
2159 | if (warned) |
2160 | { | |
2161 | location_t strlenloc = pss->second; | |
2162 | if (strlenloc != UNKNOWN_LOCATION && strlenloc != callloc) | |
2163 | inform (strlenloc, "length computed here"); | |
2164 | } | |
2165 | } | |
2166 | ||
8b57bfeb JJ |
2167 | /* Handle a memcpy-like ({mem{,p}cpy,__mem{,p}cpy_chk}) call. |
2168 | If strlen of the second argument is known and length of the third argument | |
2169 | is that plus one, strlen of the first argument is the same after this | |
2170 | call. */ | |
2171 | ||
2172 | static void | |
2173 | handle_builtin_memcpy (enum built_in_function bcode, gimple_stmt_iterator *gsi) | |
2174 | { | |
2175 | int idx, didx; | |
2176 | tree src, dst, len, lhs, oldlen, newlen; | |
355fe088 | 2177 | gimple *stmt = gsi_stmt (*gsi); |
526ceb68 | 2178 | strinfo *si, *dsi, *olddsi; |
f5fc4a04 | 2179 | bool with_bounds = gimple_call_with_bounds_p (stmt); |
8b57bfeb | 2180 | |
f5fc4a04 IE |
2181 | len = gimple_call_arg (stmt, with_bounds ? 4 : 2); |
2182 | src = gimple_call_arg (stmt, with_bounds ? 2 : 1); | |
8b57bfeb JJ |
2183 | dst = gimple_call_arg (stmt, 0); |
2184 | idx = get_stridx (src); | |
2185 | if (idx == 0) | |
2186 | return; | |
2187 | ||
2188 | didx = get_stridx (dst); | |
2189 | olddsi = NULL; | |
2190 | if (didx > 0) | |
2191 | olddsi = get_strinfo (didx); | |
2192 | else if (didx < 0) | |
2193 | return; | |
2194 | ||
2195 | if (olddsi != NULL | |
cc269bb6 | 2196 | && tree_fits_uhwi_p (len) |
8b57bfeb JJ |
2197 | && !integer_zerop (len)) |
2198 | adjust_last_stmt (olddsi, stmt, false); | |
2199 | ||
e3f9a279 | 2200 | bool full_string_p; |
8b57bfeb JJ |
2201 | if (idx > 0) |
2202 | { | |
355fe088 | 2203 | gimple *def_stmt; |
8b57bfeb | 2204 | |
e3f9a279 RS |
2205 | /* Handle memcpy (x, y, l) where l's relationship with strlen (y) |
2206 | is known. */ | |
8b57bfeb | 2207 | si = get_strinfo (idx); |
e3f9a279 | 2208 | if (si == NULL || si->nonzero_chars == NULL_TREE) |
8b57bfeb | 2209 | return; |
e3f9a279 RS |
2210 | if (TREE_CODE (len) == INTEGER_CST |
2211 | && TREE_CODE (si->nonzero_chars) == INTEGER_CST) | |
2212 | { | |
2213 | if (tree_int_cst_le (len, si->nonzero_chars)) | |
2214 | { | |
2215 | /* Copying LEN nonzero characters, where LEN is constant. */ | |
2216 | newlen = len; | |
2217 | full_string_p = false; | |
2218 | } | |
2219 | else | |
2220 | { | |
2221 | /* Copying the whole of the analyzed part of SI. */ | |
2222 | newlen = si->nonzero_chars; | |
2223 | full_string_p = si->full_string_p; | |
2224 | } | |
2225 | } | |
2226 | else | |
2227 | { | |
2228 | if (!si->full_string_p) | |
2229 | return; | |
2230 | if (TREE_CODE (len) != SSA_NAME) | |
2231 | return; | |
2232 | def_stmt = SSA_NAME_DEF_STMT (len); | |
2233 | if (!is_gimple_assign (def_stmt) | |
2234 | || gimple_assign_rhs_code (def_stmt) != PLUS_EXPR | |
2235 | || gimple_assign_rhs1 (def_stmt) != si->nonzero_chars | |
2236 | || !integer_onep (gimple_assign_rhs2 (def_stmt))) | |
2237 | return; | |
2238 | /* Copying variable-length string SI (and no more). */ | |
2239 | newlen = si->nonzero_chars; | |
2240 | full_string_p = true; | |
2241 | } | |
8b57bfeb JJ |
2242 | } |
2243 | else | |
2244 | { | |
2245 | si = NULL; | |
2246 | /* Handle memcpy (x, "abcd", 5) or | |
2247 | memcpy (x, "abc\0uvw", 7). */ | |
e3f9a279 | 2248 | if (!tree_fits_uhwi_p (len)) |
8b57bfeb | 2249 | return; |
e3f9a279 RS |
2250 | |
2251 | unsigned HOST_WIDE_INT clen = tree_to_uhwi (len); | |
2252 | unsigned HOST_WIDE_INT nonzero_chars = ~idx; | |
2253 | newlen = build_int_cst (size_type_node, MIN (nonzero_chars, clen)); | |
2254 | full_string_p = clen > nonzero_chars; | |
8b57bfeb JJ |
2255 | } |
2256 | ||
2257 | if (olddsi != NULL && TREE_CODE (len) == SSA_NAME) | |
2258 | adjust_last_stmt (olddsi, stmt, false); | |
2259 | ||
2260 | if (didx == 0) | |
2261 | { | |
2262 | didx = new_stridx (dst); | |
2263 | if (didx == 0) | |
2264 | return; | |
2265 | } | |
8b57bfeb JJ |
2266 | oldlen = NULL_TREE; |
2267 | if (olddsi != NULL) | |
2268 | { | |
2269 | dsi = unshare_strinfo (olddsi); | |
e3f9a279 RS |
2270 | oldlen = olddsi->nonzero_chars; |
2271 | dsi->nonzero_chars = newlen; | |
2272 | dsi->full_string_p = full_string_p; | |
8b57bfeb JJ |
2273 | /* Break the chain, so adjust_related_strinfo on later pointers in |
2274 | the chain won't adjust this one anymore. */ | |
2275 | dsi->next = 0; | |
2276 | dsi->stmt = NULL; | |
2277 | dsi->endptr = NULL_TREE; | |
2278 | } | |
2279 | else | |
2280 | { | |
e3f9a279 | 2281 | dsi = new_strinfo (dst, didx, newlen, full_string_p); |
8b57bfeb JJ |
2282 | set_strinfo (didx, dsi); |
2283 | find_equal_ptrs (dst, didx); | |
2284 | } | |
2285 | dsi->writable = true; | |
2286 | dsi->dont_invalidate = true; | |
2287 | if (olddsi != NULL) | |
2288 | { | |
2289 | tree adj = NULL_TREE; | |
2290 | location_t loc = gimple_location (stmt); | |
2291 | if (oldlen == NULL_TREE) | |
2292 | ; | |
2293 | else if (integer_zerop (oldlen)) | |
e3f9a279 | 2294 | adj = newlen; |
8b57bfeb | 2295 | else if (TREE_CODE (oldlen) == INTEGER_CST |
e3f9a279 RS |
2296 | || TREE_CODE (newlen) == INTEGER_CST) |
2297 | adj = fold_build2_loc (loc, MINUS_EXPR, TREE_TYPE (newlen), newlen, | |
2298 | fold_convert_loc (loc, TREE_TYPE (newlen), | |
8b57bfeb JJ |
2299 | oldlen)); |
2300 | if (adj != NULL_TREE) | |
2301 | adjust_related_strinfos (loc, dsi, adj); | |
2302 | else | |
2303 | dsi->prev = 0; | |
2304 | } | |
2305 | /* memcpy src may not overlap dst, so src doesn't need to be | |
2306 | invalidated either. */ | |
2307 | if (si != NULL) | |
2308 | si->dont_invalidate = true; | |
2309 | ||
e3f9a279 | 2310 | if (full_string_p) |
8b57bfeb | 2311 | { |
e3f9a279 RS |
2312 | lhs = gimple_call_lhs (stmt); |
2313 | switch (bcode) | |
2314 | { | |
2315 | case BUILT_IN_MEMCPY: | |
2316 | case BUILT_IN_MEMCPY_CHK: | |
2317 | case BUILT_IN_MEMCPY_CHKP: | |
2318 | case BUILT_IN_MEMCPY_CHK_CHKP: | |
2319 | /* Allow adjust_last_stmt to decrease this memcpy's size. */ | |
2320 | laststmt.stmt = stmt; | |
2321 | laststmt.len = dsi->nonzero_chars; | |
2322 | laststmt.stridx = dsi->idx; | |
2323 | if (lhs) | |
2324 | ssa_ver_to_stridx[SSA_NAME_VERSION (lhs)] = didx; | |
2325 | break; | |
2326 | case BUILT_IN_MEMPCPY: | |
2327 | case BUILT_IN_MEMPCPY_CHK: | |
2328 | case BUILT_IN_MEMPCPY_CHKP: | |
2329 | case BUILT_IN_MEMPCPY_CHK_CHKP: | |
2330 | break; | |
2331 | default: | |
2332 | gcc_unreachable (); | |
2333 | } | |
8b57bfeb JJ |
2334 | } |
2335 | } | |
2336 | ||
2337 | /* Handle a strcat-like ({strcat,__strcat_chk}) call. | |
2338 | If strlen of the second argument is known, strlen of the first argument | |
2339 | is increased by the length of the second argument. Furthermore, attempt | |
2340 | to convert it to memcpy/strcpy if the length of the first argument | |
2341 | is known. */ | |
2342 | ||
2343 | static void | |
2344 | handle_builtin_strcat (enum built_in_function bcode, gimple_stmt_iterator *gsi) | |
2345 | { | |
2346 | int idx, didx; | |
cc8bea0a | 2347 | tree srclen, args, type, fn, objsz, endptr; |
8b57bfeb | 2348 | bool success; |
355fe088 | 2349 | gimple *stmt = gsi_stmt (*gsi); |
526ceb68 | 2350 | strinfo *si, *dsi; |
cc8bea0a | 2351 | location_t loc = gimple_location (stmt); |
f5fc4a04 | 2352 | bool with_bounds = gimple_call_with_bounds_p (stmt); |
8b57bfeb | 2353 | |
cc8bea0a MS |
2354 | tree src = gimple_call_arg (stmt, with_bounds ? 2 : 1); |
2355 | tree dst = gimple_call_arg (stmt, 0); | |
2356 | ||
2357 | /* Bail if the source is the same as destination. It will be diagnosed | |
2358 | elsewhere. */ | |
2359 | if (operand_equal_p (src, dst, 0)) | |
2360 | return; | |
2361 | ||
2362 | tree lhs = gimple_call_lhs (stmt); | |
8b57bfeb JJ |
2363 | |
2364 | didx = get_stridx (dst); | |
2365 | if (didx < 0) | |
2366 | return; | |
2367 | ||
2368 | dsi = NULL; | |
2369 | if (didx > 0) | |
2370 | dsi = get_strinfo (didx); | |
cc8bea0a MS |
2371 | |
2372 | srclen = NULL_TREE; | |
2373 | si = NULL; | |
2374 | idx = get_stridx (src); | |
2375 | if (idx < 0) | |
2376 | srclen = build_int_cst (size_type_node, ~idx); | |
2377 | else if (idx > 0) | |
2378 | { | |
2379 | si = get_strinfo (idx); | |
2380 | if (si != NULL) | |
2381 | srclen = get_string_length (si); | |
2382 | } | |
2383 | ||
2384 | /* Set the no-warning bit on the transformed statement? */ | |
2385 | bool set_no_warning = false; | |
2386 | ||
8b57bfeb JJ |
2387 | if (dsi == NULL || get_string_length (dsi) == NULL_TREE) |
2388 | { | |
cc8bea0a MS |
2389 | { |
2390 | /* The concatenation always involves copying at least one byte | |
2391 | (the terminating nul), even if the source string is empty. | |
2392 | If the source is unknown assume it's one character long and | |
2393 | used that as both sizes. */ | |
2394 | tree slen = srclen; | |
2395 | if (slen) | |
2396 | { | |
2397 | tree type = TREE_TYPE (slen); | |
2398 | slen = fold_build2 (PLUS_EXPR, type, slen, build_int_cst (type, 1)); | |
2399 | } | |
2400 | ||
2401 | tree sptr = si && si->ptr ? si->ptr : src; | |
2402 | ||
2403 | if (!check_bounds_or_overlap (as_a <gcall *>(stmt), dst, sptr, | |
2404 | NULL_TREE, slen)) | |
2405 | { | |
2406 | gimple_set_no_warning (stmt, true); | |
2407 | set_no_warning = true; | |
2408 | } | |
2409 | } | |
2410 | ||
8b57bfeb | 2411 | /* strcat (p, q) can be transformed into |
cc8bea0a | 2412 | tmp = p + strlen (p); endptr = stpcpy (tmp, q); |
8b57bfeb JJ |
2413 | with length endptr - p if we need to compute the length |
2414 | later on. Don't do this transformation if we don't need | |
2415 | it. */ | |
e79983f4 | 2416 | if (builtin_decl_implicit_p (BUILT_IN_STPCPY) && lhs == NULL_TREE) |
8b57bfeb JJ |
2417 | { |
2418 | if (didx == 0) | |
2419 | { | |
2420 | didx = new_stridx (dst); | |
2421 | if (didx == 0) | |
2422 | return; | |
2423 | } | |
2424 | if (dsi == NULL) | |
2425 | { | |
e3f9a279 | 2426 | dsi = new_strinfo (dst, didx, NULL_TREE, false); |
8b57bfeb JJ |
2427 | set_strinfo (didx, dsi); |
2428 | find_equal_ptrs (dst, didx); | |
2429 | } | |
2430 | else | |
2431 | { | |
2432 | dsi = unshare_strinfo (dsi); | |
e3f9a279 RS |
2433 | dsi->nonzero_chars = NULL_TREE; |
2434 | dsi->full_string_p = false; | |
8b57bfeb JJ |
2435 | dsi->next = 0; |
2436 | dsi->endptr = NULL_TREE; | |
2437 | } | |
2438 | dsi->writable = true; | |
2439 | dsi->stmt = stmt; | |
2440 | dsi->dont_invalidate = true; | |
2441 | } | |
2442 | return; | |
2443 | } | |
2444 | ||
cc8bea0a | 2445 | tree dstlen = dsi->nonzero_chars; |
8b57bfeb JJ |
2446 | endptr = dsi->endptr; |
2447 | ||
2448 | dsi = unshare_strinfo (dsi); | |
2449 | dsi->endptr = NULL_TREE; | |
2450 | dsi->stmt = NULL; | |
2451 | dsi->writable = true; | |
2452 | ||
2453 | if (srclen != NULL_TREE) | |
2454 | { | |
e3f9a279 RS |
2455 | dsi->nonzero_chars = fold_build2_loc (loc, PLUS_EXPR, |
2456 | TREE_TYPE (dsi->nonzero_chars), | |
2457 | dsi->nonzero_chars, srclen); | |
2458 | gcc_assert (dsi->full_string_p); | |
8b57bfeb JJ |
2459 | adjust_related_strinfos (loc, dsi, srclen); |
2460 | dsi->dont_invalidate = true; | |
2461 | } | |
2462 | else | |
2463 | { | |
e3f9a279 RS |
2464 | dsi->nonzero_chars = NULL; |
2465 | dsi->full_string_p = false; | |
e79983f4 | 2466 | if (lhs == NULL_TREE && builtin_decl_implicit_p (BUILT_IN_STPCPY)) |
8b57bfeb JJ |
2467 | dsi->dont_invalidate = true; |
2468 | } | |
2469 | ||
2470 | if (si != NULL) | |
2471 | /* strcat src may not overlap dst, so src doesn't need to be | |
2472 | invalidated either. */ | |
2473 | si->dont_invalidate = true; | |
2474 | ||
2475 | /* For now. Could remove the lhs from the call and add | |
2476 | lhs = dst; afterwards. */ | |
2477 | if (lhs) | |
2478 | return; | |
2479 | ||
2480 | fn = NULL_TREE; | |
2481 | objsz = NULL_TREE; | |
2482 | switch (bcode) | |
2483 | { | |
2484 | case BUILT_IN_STRCAT: | |
f5fc4a04 | 2485 | case BUILT_IN_STRCAT_CHKP: |
8b57bfeb | 2486 | if (srclen != NULL_TREE) |
e79983f4 | 2487 | fn = builtin_decl_implicit (BUILT_IN_MEMCPY); |
8b57bfeb | 2488 | else |
e79983f4 | 2489 | fn = builtin_decl_implicit (BUILT_IN_STRCPY); |
8b57bfeb JJ |
2490 | break; |
2491 | case BUILT_IN_STRCAT_CHK: | |
f5fc4a04 | 2492 | case BUILT_IN_STRCAT_CHK_CHKP: |
8b57bfeb | 2493 | if (srclen != NULL_TREE) |
e79983f4 | 2494 | fn = builtin_decl_explicit (BUILT_IN_MEMCPY_CHK); |
8b57bfeb | 2495 | else |
e79983f4 | 2496 | fn = builtin_decl_explicit (BUILT_IN_STRCPY_CHK); |
f5fc4a04 | 2497 | objsz = gimple_call_arg (stmt, with_bounds ? 4 : 2); |
8b57bfeb JJ |
2498 | break; |
2499 | default: | |
2500 | gcc_unreachable (); | |
2501 | } | |
2502 | ||
2503 | if (fn == NULL_TREE) | |
2504 | return; | |
2505 | ||
cc8bea0a MS |
2506 | if (dsi && dstlen) |
2507 | { | |
2508 | tree type = TREE_TYPE (dstlen); | |
2509 | ||
2510 | /* Compute the size of the source sequence, including the nul. */ | |
2511 | tree srcsize = srclen ? srclen : size_zero_node; | |
2512 | srcsize = fold_build2 (PLUS_EXPR, type, srcsize, build_int_cst (type, 1)); | |
2513 | ||
2514 | tree sptr = si && si->ptr ? si->ptr : src; | |
2515 | ||
2516 | if (!check_bounds_or_overlap (as_a <gcall *>(stmt), dst, sptr, | |
2517 | dstlen, srcsize)) | |
2518 | { | |
2519 | gimple_set_no_warning (stmt, true); | |
2520 | set_no_warning = true; | |
2521 | } | |
2522 | } | |
2523 | ||
2524 | tree len = NULL_TREE; | |
8b57bfeb JJ |
2525 | if (srclen != NULL_TREE) |
2526 | { | |
2527 | args = TYPE_ARG_TYPES (TREE_TYPE (fn)); | |
2528 | type = TREE_VALUE (TREE_CHAIN (TREE_CHAIN (args))); | |
2529 | ||
2530 | len = fold_convert_loc (loc, type, unshare_expr (srclen)); | |
2531 | len = fold_build2_loc (loc, PLUS_EXPR, type, len, | |
2532 | build_int_cst (type, 1)); | |
2533 | len = force_gimple_operand_gsi (gsi, len, true, NULL_TREE, true, | |
2534 | GSI_SAME_STMT); | |
2535 | } | |
2536 | if (endptr) | |
2537 | dst = fold_convert_loc (loc, TREE_TYPE (dst), unshare_expr (endptr)); | |
2538 | else | |
2539 | dst = fold_build2_loc (loc, POINTER_PLUS_EXPR, | |
2540 | TREE_TYPE (dst), unshare_expr (dst), | |
2541 | fold_convert_loc (loc, sizetype, | |
2542 | unshare_expr (dstlen))); | |
2543 | dst = force_gimple_operand_gsi (gsi, dst, true, NULL_TREE, true, | |
2544 | GSI_SAME_STMT); | |
2545 | if (dump_file && (dump_flags & TDF_DETAILS) != 0) | |
2546 | { | |
2547 | fprintf (dump_file, "Optimizing: "); | |
2548 | print_gimple_stmt (dump_file, stmt, 0, TDF_SLIM); | |
2549 | } | |
f5fc4a04 IE |
2550 | if (with_bounds) |
2551 | { | |
2552 | fn = chkp_maybe_create_clone (fn)->decl; | |
2553 | if (srclen != NULL_TREE) | |
2554 | success = update_gimple_call (gsi, fn, 5 + (objsz != NULL_TREE), | |
2555 | dst, | |
2556 | gimple_call_arg (stmt, 1), | |
2557 | src, | |
2558 | gimple_call_arg (stmt, 3), | |
2559 | len, objsz); | |
2560 | else | |
2561 | success = update_gimple_call (gsi, fn, 4 + (objsz != NULL_TREE), | |
2562 | dst, | |
2563 | gimple_call_arg (stmt, 1), | |
2564 | src, | |
2565 | gimple_call_arg (stmt, 3), | |
2566 | objsz); | |
2567 | } | |
8b57bfeb | 2568 | else |
f5fc4a04 IE |
2569 | if (srclen != NULL_TREE) |
2570 | success = update_gimple_call (gsi, fn, 3 + (objsz != NULL_TREE), | |
2571 | dst, src, len, objsz); | |
2572 | else | |
2573 | success = update_gimple_call (gsi, fn, 2 + (objsz != NULL_TREE), | |
2574 | dst, src, objsz); | |
8b57bfeb JJ |
2575 | if (success) |
2576 | { | |
2577 | stmt = gsi_stmt (*gsi); | |
f5fc4a04 | 2578 | gimple_call_set_with_bounds (stmt, with_bounds); |
8b57bfeb JJ |
2579 | update_stmt (stmt); |
2580 | if (dump_file && (dump_flags & TDF_DETAILS) != 0) | |
2581 | { | |
2582 | fprintf (dump_file, "into: "); | |
2583 | print_gimple_stmt (dump_file, stmt, 0, TDF_SLIM); | |
2584 | } | |
2585 | /* If srclen == NULL, note that current string length can be | |
2586 | computed by transforming this strcpy into stpcpy. */ | |
2587 | if (srclen == NULL_TREE && dsi->dont_invalidate) | |
2588 | dsi->stmt = stmt; | |
2589 | adjust_last_stmt (dsi, stmt, true); | |
2590 | if (srclen != NULL_TREE) | |
2591 | { | |
2592 | laststmt.stmt = stmt; | |
2593 | laststmt.len = srclen; | |
2594 | laststmt.stridx = dsi->idx; | |
2595 | } | |
2596 | } | |
2597 | else if (dump_file && (dump_flags & TDF_DETAILS) != 0) | |
2598 | fprintf (dump_file, "not possible.\n"); | |
cc8bea0a MS |
2599 | |
2600 | if (set_no_warning) | |
2601 | gimple_set_no_warning (stmt, true); | |
8b57bfeb JJ |
2602 | } |
2603 | ||
24314386 MG |
2604 | /* Handle a call to malloc or calloc. */ |
2605 | ||
2606 | static void | |
2607 | handle_builtin_malloc (enum built_in_function bcode, gimple_stmt_iterator *gsi) | |
2608 | { | |
355fe088 | 2609 | gimple *stmt = gsi_stmt (*gsi); |
24314386 | 2610 | tree lhs = gimple_call_lhs (stmt); |
a71dcca8 ML |
2611 | if (lhs == NULL_TREE) |
2612 | return; | |
2613 | ||
24314386 MG |
2614 | gcc_assert (get_stridx (lhs) == 0); |
2615 | int idx = new_stridx (lhs); | |
2616 | tree length = NULL_TREE; | |
2617 | if (bcode == BUILT_IN_CALLOC) | |
2618 | length = build_int_cst (size_type_node, 0); | |
e3f9a279 | 2619 | strinfo *si = new_strinfo (lhs, idx, length, length != NULL_TREE); |
24314386 MG |
2620 | if (bcode == BUILT_IN_CALLOC) |
2621 | si->endptr = lhs; | |
2622 | set_strinfo (idx, si); | |
2623 | si->writable = true; | |
2624 | si->stmt = stmt; | |
2625 | si->dont_invalidate = true; | |
2626 | } | |
2627 | ||
2628 | /* Handle a call to memset. | |
2629 | After a call to calloc, memset(,0,) is unnecessary. | |
2630 | memset(malloc(n),0,n) is calloc(n,1). */ | |
2631 | ||
2632 | static bool | |
2633 | handle_builtin_memset (gimple_stmt_iterator *gsi) | |
2634 | { | |
355fe088 | 2635 | gimple *stmt2 = gsi_stmt (*gsi); |
24314386 MG |
2636 | if (!integer_zerop (gimple_call_arg (stmt2, 1))) |
2637 | return true; | |
2638 | tree ptr = gimple_call_arg (stmt2, 0); | |
2639 | int idx1 = get_stridx (ptr); | |
2640 | if (idx1 <= 0) | |
2641 | return true; | |
526ceb68 | 2642 | strinfo *si1 = get_strinfo (idx1); |
24314386 MG |
2643 | if (!si1) |
2644 | return true; | |
355fe088 | 2645 | gimple *stmt1 = si1->stmt; |
24314386 MG |
2646 | if (!stmt1 || !is_gimple_call (stmt1)) |
2647 | return true; | |
2648 | tree callee1 = gimple_call_fndecl (stmt1); | |
0ad84f34 | 2649 | if (!valid_builtin_call (stmt1)) |
24314386 MG |
2650 | return true; |
2651 | enum built_in_function code1 = DECL_FUNCTION_CODE (callee1); | |
2652 | tree size = gimple_call_arg (stmt2, 2); | |
2653 | if (code1 == BUILT_IN_CALLOC) | |
2654 | /* Not touching stmt1 */ ; | |
2655 | else if (code1 == BUILT_IN_MALLOC | |
2656 | && operand_equal_p (gimple_call_arg (stmt1, 0), size, 0)) | |
2657 | { | |
2658 | gimple_stmt_iterator gsi1 = gsi_for_stmt (stmt1); | |
2659 | update_gimple_call (&gsi1, builtin_decl_implicit (BUILT_IN_CALLOC), 2, | |
2660 | size, build_one_cst (size_type_node)); | |
e3f9a279 RS |
2661 | si1->nonzero_chars = build_int_cst (size_type_node, 0); |
2662 | si1->full_string_p = true; | |
20cb2258 | 2663 | si1->stmt = gsi_stmt (gsi1); |
24314386 MG |
2664 | } |
2665 | else | |
2666 | return true; | |
2667 | tree lhs = gimple_call_lhs (stmt2); | |
2668 | unlink_stmt_vdef (stmt2); | |
2669 | if (lhs) | |
2670 | { | |
355fe088 | 2671 | gimple *assign = gimple_build_assign (lhs, ptr); |
24314386 MG |
2672 | gsi_replace (gsi, assign, false); |
2673 | } | |
2674 | else | |
2675 | { | |
2676 | gsi_remove (gsi, true); | |
2677 | release_defs (stmt2); | |
2678 | } | |
2679 | ||
2680 | return false; | |
2681 | } | |
2682 | ||
36b85e43 BS |
2683 | /* Handle a call to memcmp. We try to handle small comparisons by |
2684 | converting them to load and compare, and replacing the call to memcmp | |
2685 | with a __builtin_memcmp_eq call where possible. */ | |
2686 | ||
2687 | static bool | |
2688 | handle_builtin_memcmp (gimple_stmt_iterator *gsi) | |
2689 | { | |
2690 | gcall *stmt2 = as_a <gcall *> (gsi_stmt (*gsi)); | |
2691 | tree res = gimple_call_lhs (stmt2); | |
2692 | tree arg1 = gimple_call_arg (stmt2, 0); | |
2693 | tree arg2 = gimple_call_arg (stmt2, 1); | |
2694 | tree len = gimple_call_arg (stmt2, 2); | |
2695 | unsigned HOST_WIDE_INT leni; | |
2696 | use_operand_p use_p; | |
2697 | imm_use_iterator iter; | |
2698 | ||
2699 | if (!res) | |
2700 | return true; | |
2701 | ||
2702 | FOR_EACH_IMM_USE_FAST (use_p, iter, res) | |
2703 | { | |
2704 | gimple *ustmt = USE_STMT (use_p); | |
2705 | ||
73d73b48 BS |
2706 | if (is_gimple_debug (ustmt)) |
2707 | continue; | |
36b85e43 BS |
2708 | if (gimple_code (ustmt) == GIMPLE_ASSIGN) |
2709 | { | |
2710 | gassign *asgn = as_a <gassign *> (ustmt); | |
2711 | tree_code code = gimple_assign_rhs_code (asgn); | |
2712 | if ((code != EQ_EXPR && code != NE_EXPR) | |
2713 | || !integer_zerop (gimple_assign_rhs2 (asgn))) | |
2714 | return true; | |
2715 | } | |
2716 | else if (gimple_code (ustmt) == GIMPLE_COND) | |
2717 | { | |
2718 | tree_code code = gimple_cond_code (ustmt); | |
2719 | if ((code != EQ_EXPR && code != NE_EXPR) | |
2720 | || !integer_zerop (gimple_cond_rhs (ustmt))) | |
2721 | return true; | |
2722 | } | |
2723 | else | |
2724 | return true; | |
2725 | } | |
2726 | ||
2727 | if (tree_fits_uhwi_p (len) | |
2728 | && (leni = tree_to_uhwi (len)) <= GET_MODE_SIZE (word_mode) | |
146ec50f | 2729 | && pow2p_hwi (leni)) |
36b85e43 BS |
2730 | { |
2731 | leni *= CHAR_TYPE_SIZE; | |
2732 | unsigned align1 = get_pointer_alignment (arg1); | |
2733 | unsigned align2 = get_pointer_alignment (arg2); | |
2734 | unsigned align = MIN (align1, align2); | |
fffbab82 RS |
2735 | scalar_int_mode mode; |
2736 | if (int_mode_for_size (leni, 1).exists (&mode) | |
e0bd6c9f | 2737 | && (align >= leni || !targetm.slow_unaligned_access (mode, align))) |
36b85e43 BS |
2738 | { |
2739 | location_t loc = gimple_location (stmt2); | |
2740 | tree type, off; | |
2741 | type = build_nonstandard_integer_type (leni, 1); | |
73a699ae | 2742 | gcc_assert (known_eq (GET_MODE_BITSIZE (TYPE_MODE (type)), leni)); |
36b85e43 BS |
2743 | tree ptrtype = build_pointer_type_for_mode (char_type_node, |
2744 | ptr_mode, true); | |
2745 | off = build_int_cst (ptrtype, 0); | |
2746 | arg1 = build2_loc (loc, MEM_REF, type, arg1, off); | |
2747 | arg2 = build2_loc (loc, MEM_REF, type, arg2, off); | |
2748 | tree tem1 = fold_const_aggregate_ref (arg1); | |
2749 | if (tem1) | |
2750 | arg1 = tem1; | |
2751 | tree tem2 = fold_const_aggregate_ref (arg2); | |
2752 | if (tem2) | |
2753 | arg2 = tem2; | |
2754 | res = fold_convert_loc (loc, TREE_TYPE (res), | |
2755 | fold_build2_loc (loc, NE_EXPR, | |
2756 | boolean_type_node, | |
2757 | arg1, arg2)); | |
2758 | gimplify_and_update_call_from_tree (gsi, res); | |
2759 | return false; | |
2760 | } | |
2761 | } | |
2762 | ||
2763 | gimple_call_set_fndecl (stmt2, builtin_decl_explicit (BUILT_IN_MEMCMP_EQ)); | |
2764 | return false; | |
2765 | } | |
2766 | ||
8b57bfeb JJ |
2767 | /* Handle a POINTER_PLUS_EXPR statement. |
2768 | For p = "abcd" + 2; compute associated length, or if | |
2769 | p = q + off is pointing to a '\0' character of a string, call | |
2770 | zero_length_string on it. */ | |
2771 | ||
2772 | static void | |
2773 | handle_pointer_plus (gimple_stmt_iterator *gsi) | |
2774 | { | |
355fe088 | 2775 | gimple *stmt = gsi_stmt (*gsi); |
8b57bfeb JJ |
2776 | tree lhs = gimple_assign_lhs (stmt), off; |
2777 | int idx = get_stridx (gimple_assign_rhs1 (stmt)); | |
526ceb68 | 2778 | strinfo *si, *zsi; |
8b57bfeb JJ |
2779 | |
2780 | if (idx == 0) | |
2781 | return; | |
2782 | ||
2783 | if (idx < 0) | |
2784 | { | |
2785 | tree off = gimple_assign_rhs2 (stmt); | |
cc269bb6 | 2786 | if (tree_fits_uhwi_p (off) |
7d362f6c | 2787 | && tree_to_uhwi (off) <= (unsigned HOST_WIDE_INT) ~idx) |
9771b263 | 2788 | ssa_ver_to_stridx[SSA_NAME_VERSION (lhs)] |
ae7e9ddd | 2789 | = ~(~idx - (int) tree_to_uhwi (off)); |
8b57bfeb JJ |
2790 | return; |
2791 | } | |
2792 | ||
2793 | si = get_strinfo (idx); | |
e3f9a279 | 2794 | if (si == NULL || si->nonzero_chars == NULL_TREE) |
8b57bfeb JJ |
2795 | return; |
2796 | ||
2797 | off = gimple_assign_rhs2 (stmt); | |
2798 | zsi = NULL; | |
e3f9a279 | 2799 | if (si->full_string_p && operand_equal_p (si->nonzero_chars, off, 0)) |
8b57bfeb JJ |
2800 | zsi = zero_length_string (lhs, si); |
2801 | else if (TREE_CODE (off) == SSA_NAME) | |
2802 | { | |
355fe088 | 2803 | gimple *def_stmt = SSA_NAME_DEF_STMT (off); |
8b57bfeb | 2804 | if (gimple_assign_single_p (def_stmt) |
e3f9a279 RS |
2805 | && si->full_string_p |
2806 | && operand_equal_p (si->nonzero_chars, | |
2807 | gimple_assign_rhs1 (def_stmt), 0)) | |
8b57bfeb JJ |
2808 | zsi = zero_length_string (lhs, si); |
2809 | } | |
2810 | if (zsi != NULL | |
2811 | && si->endptr != NULL_TREE | |
2812 | && si->endptr != lhs | |
2813 | && TREE_CODE (si->endptr) == SSA_NAME) | |
2814 | { | |
2815 | enum tree_code rhs_code | |
2816 | = useless_type_conversion_p (TREE_TYPE (lhs), TREE_TYPE (si->endptr)) | |
2817 | ? SSA_NAME : NOP_EXPR; | |
00d66391 | 2818 | gimple_assign_set_rhs_with_ops (gsi, rhs_code, si->endptr); |
8b57bfeb JJ |
2819 | gcc_assert (gsi_stmt (*gsi) == stmt); |
2820 | update_stmt (stmt); | |
2821 | } | |
2822 | } | |
2823 | ||
a011292a MS |
2824 | /* If RHS, either directly or indirectly, refers to a string of constant |
2825 | length, return it. Otherwise return a negative value. */ | |
2826 | ||
2827 | static HOST_WIDE_INT | |
2828 | get_string_cst_length (tree rhs) | |
65f2d1ee PK |
2829 | { |
2830 | if (TREE_CODE (rhs) == MEM_REF | |
2831 | && integer_zerop (TREE_OPERAND (rhs, 1))) | |
2832 | { | |
a011292a | 2833 | rhs = TREE_OPERAND (rhs, 0); |
65f2d1ee | 2834 | if (TREE_CODE (rhs) == ADDR_EXPR) |
05ef3173 | 2835 | { |
a011292a MS |
2836 | tree rhs_addr = rhs; |
2837 | ||
05ef3173 MS |
2838 | rhs = TREE_OPERAND (rhs, 0); |
2839 | if (TREE_CODE (rhs) != STRING_CST) | |
2840 | { | |
2841 | int idx = get_stridx (rhs_addr); | |
2842 | if (idx > 0) | |
2843 | { | |
2844 | strinfo *si = get_strinfo (idx); | |
a011292a MS |
2845 | if (si |
2846 | && si->full_string_p | |
2847 | && tree_fits_shwi_p (si->nonzero_chars)) | |
05ef3173 MS |
2848 | return tree_to_shwi (si->nonzero_chars); |
2849 | } | |
2850 | } | |
2851 | } | |
2852 | } | |
2853 | ||
2854 | if (TREE_CODE (rhs) == VAR_DECL | |
2855 | && TREE_READONLY (rhs)) | |
2856 | rhs = DECL_INITIAL (rhs); | |
2857 | ||
2858 | if (rhs && TREE_CODE (rhs) == STRING_CST) | |
a011292a | 2859 | return strlen (TREE_STRING_POINTER (rhs)); |
65f2d1ee | 2860 | |
05ef3173 | 2861 | return -1; |
65f2d1ee PK |
2862 | } |
2863 | ||
8b57bfeb JJ |
2864 | /* Handle a single character store. */ |
2865 | ||
2866 | static bool | |
2867 | handle_char_store (gimple_stmt_iterator *gsi) | |
2868 | { | |
2869 | int idx = -1; | |
526ceb68 | 2870 | strinfo *si = NULL; |
355fe088 | 2871 | gimple *stmt = gsi_stmt (*gsi); |
8b57bfeb | 2872 | tree ssaname = NULL_TREE, lhs = gimple_assign_lhs (stmt); |
e3f9a279 RS |
2873 | tree rhs = gimple_assign_rhs1 (stmt); |
2874 | unsigned HOST_WIDE_INT offset = 0; | |
8b57bfeb JJ |
2875 | |
2876 | if (TREE_CODE (lhs) == MEM_REF | |
2877 | && TREE_CODE (TREE_OPERAND (lhs, 0)) == SSA_NAME) | |
2878 | { | |
e3f9a279 RS |
2879 | tree mem_offset = TREE_OPERAND (lhs, 1); |
2880 | if (tree_fits_uhwi_p (mem_offset)) | |
8b57bfeb | 2881 | { |
e3f9a279 RS |
2882 | /* Get the strinfo for the base, and use it if it starts with at |
2883 | least OFFSET nonzero characters. This is trivially true if | |
2884 | OFFSET is zero. */ | |
2885 | offset = tree_to_uhwi (mem_offset); | |
2886 | idx = get_stridx (TREE_OPERAND (lhs, 0)); | |
2887 | if (idx > 0) | |
2888 | si = get_strinfo (idx); | |
2889 | if (offset == 0) | |
2890 | ssaname = TREE_OPERAND (lhs, 0); | |
2891 | else if (si == NULL || compare_nonzero_chars (si, offset) < 0) | |
2892 | return true; | |
8b57bfeb JJ |
2893 | } |
2894 | } | |
2895 | else | |
e3f9a279 RS |
2896 | { |
2897 | idx = get_addr_stridx (lhs, NULL_TREE, &offset); | |
2898 | if (idx > 0) | |
2899 | si = get_strinfo (idx); | |
2900 | } | |
8b57bfeb | 2901 | |
e3f9a279 RS |
2902 | bool storing_zero_p = initializer_zerop (rhs); |
2903 | bool storing_nonzero_p = (!storing_zero_p | |
2904 | && TREE_CODE (rhs) == INTEGER_CST | |
2905 | && integer_nonzerop (rhs)); | |
a011292a MS |
2906 | /* Set to the length of the string being assigned if known. */ |
2907 | HOST_WIDE_INT rhslen; | |
e3f9a279 RS |
2908 | |
2909 | if (si != NULL) | |
8b57bfeb | 2910 | { |
e3f9a279 RS |
2911 | int cmp = compare_nonzero_chars (si, offset); |
2912 | gcc_assert (offset == 0 || cmp >= 0); | |
2913 | if (storing_zero_p && cmp == 0 && si->full_string_p) | |
8b57bfeb | 2914 | { |
e3f9a279 RS |
2915 | /* When overwriting a '\0' with a '\0', the store can be removed |
2916 | if we know it has been stored in the current function. */ | |
2917 | if (!stmt_could_throw_p (stmt) && si->writable) | |
8b57bfeb | 2918 | { |
e3f9a279 RS |
2919 | unlink_stmt_vdef (stmt); |
2920 | release_defs (stmt); | |
2921 | gsi_remove (gsi, true); | |
2922 | return false; | |
8b57bfeb JJ |
2923 | } |
2924 | else | |
e3f9a279 RS |
2925 | { |
2926 | si->writable = true; | |
2927 | gsi_next (gsi); | |
2928 | return false; | |
2929 | } | |
8b57bfeb | 2930 | } |
e3f9a279 | 2931 | /* If si->nonzero_chars > OFFSET, we aren't overwriting '\0', |
5b115c1f MP |
2932 | and if we aren't storing '\0', we know that the length of the |
2933 | string and any other zero terminated string in memory remains | |
2934 | the same. In that case we move to the next gimple statement and | |
2935 | return to signal the caller that it shouldn't invalidate anything. | |
2936 | ||
2937 | This is benefical for cases like: | |
2938 | ||
2939 | char p[20]; | |
2940 | void foo (char *q) | |
2941 | { | |
2942 | strcpy (p, "foobar"); | |
2943 | size_t len = strlen (p); // This can be optimized into 6 | |
2944 | size_t len2 = strlen (q); // This has to be computed | |
2945 | p[0] = 'X'; | |
2946 | size_t len3 = strlen (p); // This can be optimized into 6 | |
2947 | size_t len4 = strlen (q); // This can be optimized into len2 | |
2948 | bar (len, len2, len3, len4); | |
2949 | } | |
2950 | */ | |
e3f9a279 | 2951 | else if (storing_nonzero_p && cmp > 0) |
5b115c1f MP |
2952 | { |
2953 | gsi_next (gsi); | |
2954 | return false; | |
2955 | } | |
e3f9a279 RS |
2956 | else if (storing_zero_p || storing_nonzero_p || (offset != 0 && cmp > 0)) |
2957 | { | |
2958 | /* When storing_nonzero_p, we know that the string now starts | |
2959 | with OFFSET + 1 nonzero characters, but don't know whether | |
2960 | there's a following nul terminator. | |
2961 | ||
2962 | When storing_zero_p, we know that the string is now OFFSET | |
2963 | characters long. | |
2964 | ||
2965 | Otherwise, we're storing an unknown value at offset OFFSET, | |
2966 | so need to clip the nonzero_chars to OFFSET. */ | |
2967 | location_t loc = gimple_location (stmt); | |
2968 | tree oldlen = si->nonzero_chars; | |
2969 | if (cmp == 0 && si->full_string_p) | |
2970 | /* We're overwriting the nul terminator with a nonzero or | |
2971 | unknown character. If the previous stmt was a memcpy, | |
2972 | its length may be decreased. */ | |
2973 | adjust_last_stmt (si, stmt, false); | |
2974 | si = unshare_strinfo (si); | |
2975 | if (storing_nonzero_p) | |
2976 | si->nonzero_chars = build_int_cst (size_type_node, offset + 1); | |
2977 | else | |
2978 | si->nonzero_chars = build_int_cst (size_type_node, offset); | |
2979 | si->full_string_p = storing_zero_p; | |
2980 | if (storing_zero_p | |
2981 | && ssaname | |
2982 | && !SSA_NAME_OCCURS_IN_ABNORMAL_PHI (ssaname)) | |
2983 | si->endptr = ssaname; | |
2984 | else | |
2985 | si->endptr = NULL; | |
2986 | si->next = 0; | |
2987 | si->stmt = NULL; | |
2988 | si->writable = true; | |
2989 | si->dont_invalidate = true; | |
2990 | if (oldlen) | |
2991 | { | |
2992 | tree adj = fold_build2_loc (loc, MINUS_EXPR, size_type_node, | |
2993 | si->nonzero_chars, oldlen); | |
2994 | adjust_related_strinfos (loc, si, adj); | |
2995 | } | |
2996 | else | |
2997 | si->prev = 0; | |
2998 | } | |
8b57bfeb | 2999 | } |
e3f9a279 | 3000 | else if (idx == 0 && (storing_zero_p || storing_nonzero_p)) |
8b57bfeb JJ |
3001 | { |
3002 | if (ssaname) | |
e3f9a279 | 3003 | idx = new_stridx (ssaname); |
8b57bfeb | 3004 | else |
e3f9a279 RS |
3005 | idx = new_addr_stridx (lhs); |
3006 | if (idx != 0) | |
8b57bfeb | 3007 | { |
e3f9a279 RS |
3008 | tree ptr = (ssaname ? ssaname : build_fold_addr_expr (lhs)); |
3009 | tree len = storing_nonzero_p ? size_one_node : size_zero_node; | |
3010 | si = new_strinfo (ptr, idx, len, storing_zero_p); | |
3011 | set_strinfo (idx, si); | |
3012 | if (storing_zero_p | |
3013 | && ssaname | |
3014 | && !SSA_NAME_OCCURS_IN_ABNORMAL_PHI (ssaname)) | |
3015 | si->endptr = ssaname; | |
3016 | si->dont_invalidate = true; | |
3017 | si->writable = true; | |
8b57bfeb | 3018 | } |
8b57bfeb | 3019 | } |
198fe1bf | 3020 | else if (idx == 0 |
a011292a | 3021 | && (rhslen = get_string_cst_length (gimple_assign_rhs1 (stmt))) >= 0 |
198fe1bf JJ |
3022 | && ssaname == NULL_TREE |
3023 | && TREE_CODE (TREE_TYPE (lhs)) == ARRAY_TYPE) | |
3024 | { | |
198fe1bf | 3025 | HOST_WIDE_INT a = int_size_in_bytes (TREE_TYPE (lhs)); |
05ef3173 | 3026 | if (a > 0 && (unsigned HOST_WIDE_INT) a > (unsigned HOST_WIDE_INT) rhslen) |
198fe1bf JJ |
3027 | { |
3028 | int idx = new_addr_stridx (lhs); | |
3029 | if (idx != 0) | |
3030 | { | |
3031 | si = new_strinfo (build_fold_addr_expr (lhs), idx, | |
05ef3173 | 3032 | build_int_cst (size_type_node, rhslen), true); |
198fe1bf JJ |
3033 | set_strinfo (idx, si); |
3034 | si->dont_invalidate = true; | |
3035 | } | |
3036 | } | |
3037 | } | |
8b57bfeb | 3038 | |
e3f9a279 | 3039 | if (si != NULL && offset == 0 && storing_zero_p) |
8b57bfeb JJ |
3040 | { |
3041 | /* Allow adjust_last_stmt to remove it if the stored '\0' | |
3042 | is immediately overwritten. */ | |
3043 | laststmt.stmt = stmt; | |
3044 | laststmt.len = build_int_cst (size_type_node, 1); | |
3045 | laststmt.stridx = si->idx; | |
3046 | } | |
3047 | return true; | |
3048 | } | |
3049 | ||
f368600f | 3050 | /* Try to fold strstr (s, t) eq/ne s to strncmp (s, t, strlen (t)) eq/ne 0. */ |
3b1970cb PK |
3051 | |
3052 | static void | |
f368600f | 3053 | fold_strstr_to_strncmp (tree rhs1, tree rhs2, gimple *stmt) |
3b1970cb PK |
3054 | { |
3055 | if (TREE_CODE (rhs1) != SSA_NAME | |
3056 | || TREE_CODE (rhs2) != SSA_NAME) | |
3057 | return; | |
3058 | ||
3059 | gimple *call_stmt = NULL; | |
3060 | for (int pass = 0; pass < 2; pass++) | |
3061 | { | |
3062 | gimple *g = SSA_NAME_DEF_STMT (rhs1); | |
3063 | if (gimple_call_builtin_p (g, BUILT_IN_STRSTR) | |
3064 | && has_single_use (rhs1) | |
3065 | && gimple_call_arg (g, 0) == rhs2) | |
3066 | { | |
3067 | call_stmt = g; | |
3068 | break; | |
3069 | } | |
3070 | std::swap (rhs1, rhs2); | |
3071 | } | |
3072 | ||
3073 | if (call_stmt) | |
3074 | { | |
3075 | tree arg0 = gimple_call_arg (call_stmt, 0); | |
3076 | ||
3077 | if (arg0 == rhs2) | |
3078 | { | |
3079 | tree arg1 = gimple_call_arg (call_stmt, 1); | |
3080 | tree arg1_len = NULL_TREE; | |
3081 | int idx = get_stridx (arg1); | |
3082 | ||
3083 | if (idx) | |
3084 | { | |
3085 | if (idx < 0) | |
3086 | arg1_len = build_int_cst (size_type_node, ~idx); | |
3087 | else | |
3088 | { | |
3089 | strinfo *si = get_strinfo (idx); | |
3090 | if (si) | |
3091 | arg1_len = get_string_length (si); | |
3092 | } | |
3093 | } | |
3094 | ||
3095 | if (arg1_len != NULL_TREE) | |
3096 | { | |
3097 | gimple_stmt_iterator gsi = gsi_for_stmt (call_stmt); | |
f368600f | 3098 | tree strncmp_decl = builtin_decl_explicit (BUILT_IN_STRNCMP); |
96863f32 ML |
3099 | |
3100 | if (!is_gimple_val (arg1_len)) | |
3101 | { | |
3102 | tree arg1_len_tmp = make_ssa_name (TREE_TYPE (arg1_len)); | |
3103 | gassign *arg1_stmt = gimple_build_assign (arg1_len_tmp, | |
3104 | arg1_len); | |
3105 | gsi_insert_before (&gsi, arg1_stmt, GSI_SAME_STMT); | |
3106 | arg1_len = arg1_len_tmp; | |
3107 | } | |
3108 | ||
f368600f | 3109 | gcall *strncmp_call = gimple_build_call (strncmp_decl, 3, |
3b1970cb | 3110 | arg0, arg1, arg1_len); |
f368600f ML |
3111 | tree strncmp_lhs = make_ssa_name (integer_type_node); |
3112 | gimple_set_vuse (strncmp_call, gimple_vuse (call_stmt)); | |
3113 | gimple_call_set_lhs (strncmp_call, strncmp_lhs); | |
3b1970cb | 3114 | gsi_remove (&gsi, true); |
f368600f ML |
3115 | gsi_insert_before (&gsi, strncmp_call, GSI_SAME_STMT); |
3116 | tree zero = build_zero_cst (TREE_TYPE (strncmp_lhs)); | |
3b1970cb PK |
3117 | |
3118 | if (is_gimple_assign (stmt)) | |
3119 | { | |
3120 | if (gimple_assign_rhs_code (stmt) == COND_EXPR) | |
3121 | { | |
3122 | tree cond = gimple_assign_rhs1 (stmt); | |
f368600f | 3123 | TREE_OPERAND (cond, 0) = strncmp_lhs; |
3b1970cb PK |
3124 | TREE_OPERAND (cond, 1) = zero; |
3125 | } | |
3126 | else | |
3127 | { | |
f368600f | 3128 | gimple_assign_set_rhs1 (stmt, strncmp_lhs); |
3b1970cb PK |
3129 | gimple_assign_set_rhs2 (stmt, zero); |
3130 | } | |
3131 | } | |
3132 | else | |
3133 | { | |
3134 | gcond *cond = as_a<gcond *> (stmt); | |
f368600f | 3135 | gimple_cond_set_lhs (cond, strncmp_lhs); |
3b1970cb PK |
3136 | gimple_cond_set_rhs (cond, zero); |
3137 | } | |
3138 | update_stmt (stmt); | |
3139 | } | |
3140 | } | |
3141 | } | |
3142 | } | |
3143 | ||
cc8bea0a | 3144 | /* Attempt to check for validity of the performed access a single statement |
fa9544ab ML |
3145 | at *GSI using string length knowledge, and to optimize it. |
3146 | If the given basic block needs clean-up of EH, CLEANUP_EH is set to | |
3147 | true. */ | |
8b57bfeb JJ |
3148 | |
3149 | static bool | |
fa9544ab | 3150 | strlen_check_and_optimize_stmt (gimple_stmt_iterator *gsi, bool *cleanup_eh) |
8b57bfeb | 3151 | { |
355fe088 | 3152 | gimple *stmt = gsi_stmt (*gsi); |
8b57bfeb JJ |
3153 | |
3154 | if (is_gimple_call (stmt)) | |
3155 | { | |
3156 | tree callee = gimple_call_fndecl (stmt); | |
0ad84f34 | 3157 | if (valid_builtin_call (stmt)) |
8b57bfeb JJ |
3158 | switch (DECL_FUNCTION_CODE (callee)) |
3159 | { | |
3160 | case BUILT_IN_STRLEN: | |
f5fc4a04 | 3161 | case BUILT_IN_STRLEN_CHKP: |
8b57bfeb JJ |
3162 | handle_builtin_strlen (gsi); |
3163 | break; | |
3164 | case BUILT_IN_STRCHR: | |
f5fc4a04 | 3165 | case BUILT_IN_STRCHR_CHKP: |
8b57bfeb JJ |
3166 | handle_builtin_strchr (gsi); |
3167 | break; | |
3168 | case BUILT_IN_STRCPY: | |
3169 | case BUILT_IN_STRCPY_CHK: | |
3170 | case BUILT_IN_STPCPY: | |
3171 | case BUILT_IN_STPCPY_CHK: | |
f5fc4a04 IE |
3172 | case BUILT_IN_STRCPY_CHKP: |
3173 | case BUILT_IN_STRCPY_CHK_CHKP: | |
3174 | case BUILT_IN_STPCPY_CHKP: | |
3175 | case BUILT_IN_STPCPY_CHK_CHKP: | |
8b57bfeb JJ |
3176 | handle_builtin_strcpy (DECL_FUNCTION_CODE (callee), gsi); |
3177 | break; | |
025d57f0 MS |
3178 | |
3179 | case BUILT_IN_STRNCAT: | |
3180 | case BUILT_IN_STRNCAT_CHK: | |
3181 | handle_builtin_strncat (DECL_FUNCTION_CODE (callee), gsi); | |
3182 | break; | |
3183 | ||
3184 | case BUILT_IN_STPNCPY: | |
3185 | case BUILT_IN_STPNCPY_CHK: | |
3186 | case BUILT_IN_STRNCPY: | |
3187 | case BUILT_IN_STRNCPY_CHK: | |
3188 | handle_builtin_stxncpy (DECL_FUNCTION_CODE (callee), gsi); | |
3189 | break; | |
3190 | ||
8b57bfeb JJ |
3191 | case BUILT_IN_MEMCPY: |
3192 | case BUILT_IN_MEMCPY_CHK: | |
3193 | case BUILT_IN_MEMPCPY: | |
3194 | case BUILT_IN_MEMPCPY_CHK: | |
f5fc4a04 IE |
3195 | case BUILT_IN_MEMCPY_CHKP: |
3196 | case BUILT_IN_MEMCPY_CHK_CHKP: | |
3197 | case BUILT_IN_MEMPCPY_CHKP: | |
3198 | case BUILT_IN_MEMPCPY_CHK_CHKP: | |
8b57bfeb JJ |
3199 | handle_builtin_memcpy (DECL_FUNCTION_CODE (callee), gsi); |
3200 | break; | |
3201 | case BUILT_IN_STRCAT: | |
3202 | case BUILT_IN_STRCAT_CHK: | |
f5fc4a04 IE |
3203 | case BUILT_IN_STRCAT_CHKP: |
3204 | case BUILT_IN_STRCAT_CHK_CHKP: | |
8b57bfeb JJ |
3205 | handle_builtin_strcat (DECL_FUNCTION_CODE (callee), gsi); |
3206 | break; | |
24314386 MG |
3207 | case BUILT_IN_MALLOC: |
3208 | case BUILT_IN_CALLOC: | |
3209 | handle_builtin_malloc (DECL_FUNCTION_CODE (callee), gsi); | |
3210 | break; | |
3211 | case BUILT_IN_MEMSET: | |
3212 | if (!handle_builtin_memset (gsi)) | |
3213 | return false; | |
3214 | break; | |
36b85e43 BS |
3215 | case BUILT_IN_MEMCMP: |
3216 | if (!handle_builtin_memcmp (gsi)) | |
3217 | return false; | |
3218 | break; | |
8b57bfeb JJ |
3219 | default: |
3220 | break; | |
3221 | } | |
3222 | } | |
5004bd00 | 3223 | else if (is_gimple_assign (stmt) && !gimple_clobber_p (stmt)) |
8b57bfeb JJ |
3224 | { |
3225 | tree lhs = gimple_assign_lhs (stmt); | |
3226 | ||
3227 | if (TREE_CODE (lhs) == SSA_NAME && POINTER_TYPE_P (TREE_TYPE (lhs))) | |
3228 | { | |
3229 | if (gimple_assign_single_p (stmt) | |
3230 | || (gimple_assign_cast_p (stmt) | |
3231 | && POINTER_TYPE_P (TREE_TYPE (gimple_assign_rhs1 (stmt))))) | |
3232 | { | |
3233 | int idx = get_stridx (gimple_assign_rhs1 (stmt)); | |
9771b263 | 3234 | ssa_ver_to_stridx[SSA_NAME_VERSION (lhs)] = idx; |
8b57bfeb JJ |
3235 | } |
3236 | else if (gimple_assign_rhs_code (stmt) == POINTER_PLUS_EXPR) | |
3237 | handle_pointer_plus (gsi); | |
3238 | } | |
3b1970cb PK |
3239 | else if (TREE_CODE (lhs) == SSA_NAME && INTEGRAL_TYPE_P (TREE_TYPE (lhs))) |
3240 | { | |
3241 | enum tree_code code = gimple_assign_rhs_code (stmt); | |
3242 | if (code == COND_EXPR) | |
3243 | { | |
3244 | tree cond = gimple_assign_rhs1 (stmt); | |
3245 | enum tree_code cond_code = TREE_CODE (cond); | |
3246 | ||
3247 | if (cond_code == EQ_EXPR || cond_code == NE_EXPR) | |
f368600f ML |
3248 | fold_strstr_to_strncmp (TREE_OPERAND (cond, 0), |
3249 | TREE_OPERAND (cond, 1), stmt); | |
3b1970cb PK |
3250 | } |
3251 | else if (code == EQ_EXPR || code == NE_EXPR) | |
f368600f ML |
3252 | fold_strstr_to_strncmp (gimple_assign_rhs1 (stmt), |
3253 | gimple_assign_rhs2 (stmt), stmt); | |
f744bfec JJ |
3254 | else if (gimple_assign_load_p (stmt) |
3255 | && TREE_CODE (TREE_TYPE (lhs)) == INTEGER_TYPE | |
3256 | && TYPE_MODE (TREE_TYPE (lhs)) == TYPE_MODE (char_type_node) | |
3257 | && (TYPE_PRECISION (TREE_TYPE (lhs)) | |
3258 | == TYPE_PRECISION (char_type_node)) | |
3259 | && !gimple_has_volatile_ops (stmt)) | |
3260 | { | |
3261 | tree off = integer_zero_node; | |
3262 | unsigned HOST_WIDE_INT coff = 0; | |
ad2a970f | 3263 | int idx = 0; |
f744bfec JJ |
3264 | tree rhs1 = gimple_assign_rhs1 (stmt); |
3265 | if (code == MEM_REF) | |
3266 | { | |
3267 | idx = get_stridx (TREE_OPERAND (rhs1, 0)); | |
ad2a970f JJ |
3268 | if (idx > 0) |
3269 | { | |
3270 | strinfo *si = get_strinfo (idx); | |
3271 | if (si | |
3272 | && si->nonzero_chars | |
3273 | && TREE_CODE (si->nonzero_chars) == INTEGER_CST | |
3274 | && (wi::to_widest (si->nonzero_chars) | |
3275 | >= wi::to_widest (off))) | |
3276 | off = TREE_OPERAND (rhs1, 1); | |
3277 | else | |
3278 | /* This case is not useful. See if get_addr_stridx | |
3279 | returns something usable. */ | |
3280 | idx = 0; | |
3281 | } | |
f744bfec | 3282 | } |
ad2a970f | 3283 | if (idx <= 0) |
f744bfec JJ |
3284 | idx = get_addr_stridx (rhs1, NULL_TREE, &coff); |
3285 | if (idx > 0) | |
3286 | { | |
3287 | strinfo *si = get_strinfo (idx); | |
3288 | if (si | |
3289 | && si->nonzero_chars | |
3290 | && TREE_CODE (si->nonzero_chars) == INTEGER_CST) | |
3291 | { | |
3292 | widest_int w1 = wi::to_widest (si->nonzero_chars); | |
3293 | widest_int w2 = wi::to_widest (off) + coff; | |
3294 | if (w1 == w2 | |
3295 | && si->full_string_p) | |
3296 | { | |
fa9544ab ML |
3297 | if (dump_file && (dump_flags & TDF_DETAILS) != 0) |
3298 | { | |
3299 | fprintf (dump_file, "Optimizing: "); | |
3300 | print_gimple_stmt (dump_file, stmt, 0, TDF_SLIM); | |
3301 | } | |
3302 | ||
f744bfec JJ |
3303 | /* Reading the final '\0' character. */ |
3304 | tree zero = build_int_cst (TREE_TYPE (lhs), 0); | |
3305 | gimple_set_vuse (stmt, NULL_TREE); | |
3306 | gimple_assign_set_rhs_from_tree (gsi, zero); | |
fa9544ab ML |
3307 | *cleanup_eh |
3308 | |= maybe_clean_or_replace_eh_stmt (stmt, | |
3309 | gsi_stmt (*gsi)); | |
3310 | stmt = gsi_stmt (*gsi); | |
3311 | update_stmt (stmt); | |
3312 | ||
3313 | if (dump_file && (dump_flags & TDF_DETAILS) != 0) | |
3314 | { | |
3315 | fprintf (dump_file, "into: "); | |
3316 | print_gimple_stmt (dump_file, stmt, 0, TDF_SLIM); | |
3317 | } | |
f744bfec JJ |
3318 | } |
3319 | else if (w1 > w2) | |
3320 | { | |
3321 | /* Reading a character before the final '\0' | |
3322 | character. Just set the value range to ~[0, 0] | |
3323 | if we don't have anything better. */ | |
3324 | wide_int min, max; | |
3325 | tree type = TREE_TYPE (lhs); | |
3326 | enum value_range_type vr | |
3327 | = get_range_info (lhs, &min, &max); | |
3328 | if (vr == VR_VARYING | |
3329 | || (vr == VR_RANGE | |
3330 | && min == wi::min_value (TYPE_PRECISION (type), | |
3331 | TYPE_SIGN (type)) | |
3332 | && max == wi::max_value (TYPE_PRECISION (type), | |
3333 | TYPE_SIGN (type)))) | |
3334 | set_range_info (lhs, VR_ANTI_RANGE, | |
3335 | wi::zero (TYPE_PRECISION (type)), | |
3336 | wi::zero (TYPE_PRECISION (type))); | |
3337 | } | |
3338 | } | |
3339 | } | |
3340 | } | |
025d57f0 | 3341 | |
6a33d0ff MS |
3342 | if (strlen_to_stridx) |
3343 | { | |
3344 | tree rhs1 = gimple_assign_rhs1 (stmt); | |
3345 | if (stridx_strlenloc *ps = strlen_to_stridx->get (rhs1)) | |
3346 | strlen_to_stridx->put (lhs, stridx_strlenloc (*ps)); | |
3347 | } | |
3b1970cb PK |
3348 | } |
3349 | else if (TREE_CODE (lhs) != SSA_NAME && !TREE_SIDE_EFFECTS (lhs)) | |
8b57bfeb JJ |
3350 | { |
3351 | tree type = TREE_TYPE (lhs); | |
3352 | if (TREE_CODE (type) == ARRAY_TYPE) | |
3353 | type = TREE_TYPE (type); | |
3354 | if (TREE_CODE (type) == INTEGER_TYPE | |
3355 | && TYPE_MODE (type) == TYPE_MODE (char_type_node) | |
3356 | && TYPE_PRECISION (type) == TYPE_PRECISION (char_type_node)) | |
3357 | { | |
3358 | if (! handle_char_store (gsi)) | |
3359 | return false; | |
3360 | } | |
3361 | } | |
3362 | } | |
3b1970cb PK |
3363 | else if (gcond *cond = dyn_cast<gcond *> (stmt)) |
3364 | { | |
3365 | enum tree_code code = gimple_cond_code (cond); | |
3366 | if (code == EQ_EXPR || code == NE_EXPR) | |
f368600f ML |
3367 | fold_strstr_to_strncmp (gimple_cond_lhs (stmt), |
3368 | gimple_cond_rhs (stmt), stmt); | |
3b1970cb | 3369 | } |
8b57bfeb JJ |
3370 | |
3371 | if (gimple_vdef (stmt)) | |
3372 | maybe_invalidate (stmt); | |
3373 | return true; | |
3374 | } | |
3375 | ||
3376 | /* Recursively call maybe_invalidate on stmts that might be executed | |
3377 | in between dombb and current bb and that contain a vdef. Stop when | |
3378 | *count stmts are inspected, or if the whole strinfo vector has | |
3379 | been invalidated. */ | |
3380 | ||
3381 | static void | |
355fe088 | 3382 | do_invalidate (basic_block dombb, gimple *phi, bitmap visited, int *count) |
8b57bfeb JJ |
3383 | { |
3384 | unsigned int i, n = gimple_phi_num_args (phi); | |
3385 | ||
3386 | for (i = 0; i < n; i++) | |
3387 | { | |
3388 | tree vuse = gimple_phi_arg_def (phi, i); | |
355fe088 | 3389 | gimple *stmt = SSA_NAME_DEF_STMT (vuse); |
8b57bfeb JJ |
3390 | basic_block bb = gimple_bb (stmt); |
3391 | if (bb == NULL | |
3392 | || bb == dombb | |
3393 | || !bitmap_set_bit (visited, bb->index) | |
3394 | || !dominated_by_p (CDI_DOMINATORS, bb, dombb)) | |
3395 | continue; | |
3396 | while (1) | |
3397 | { | |
3398 | if (gimple_code (stmt) == GIMPLE_PHI) | |
3399 | { | |
3400 | do_invalidate (dombb, stmt, visited, count); | |
3401 | if (*count == 0) | |
3402 | return; | |
3403 | break; | |
3404 | } | |
3405 | if (--*count == 0) | |
3406 | return; | |
3407 | if (!maybe_invalidate (stmt)) | |
3408 | { | |
3409 | *count = 0; | |
3410 | return; | |
3411 | } | |
3412 | vuse = gimple_vuse (stmt); | |
3413 | stmt = SSA_NAME_DEF_STMT (vuse); | |
3414 | if (gimple_bb (stmt) != bb) | |
3415 | { | |
3416 | bb = gimple_bb (stmt); | |
3417 | if (bb == NULL | |
3418 | || bb == dombb | |
3419 | || !bitmap_set_bit (visited, bb->index) | |
3420 | || !dominated_by_p (CDI_DOMINATORS, bb, dombb)) | |
3421 | break; | |
3422 | } | |
3423 | } | |
3424 | } | |
3425 | } | |
3426 | ||
4d9192b5 TS |
3427 | class strlen_dom_walker : public dom_walker |
3428 | { | |
3429 | public: | |
fa9544ab ML |
3430 | strlen_dom_walker (cdi_direction direction) |
3431 | : dom_walker (direction), m_cleanup_cfg (false) | |
3432 | {} | |
4d9192b5 | 3433 | |
3daacdcd | 3434 | virtual edge before_dom_children (basic_block); |
4d9192b5 | 3435 | virtual void after_dom_children (basic_block); |
fa9544ab ML |
3436 | |
3437 | /* Flag that will trigger TODO_cleanup_cfg to be returned in strlen | |
3438 | execute function. */ | |
3439 | bool m_cleanup_cfg; | |
4d9192b5 TS |
3440 | }; |
3441 | ||
8b57bfeb | 3442 | /* Callback for walk_dominator_tree. Attempt to optimize various |
c7880c8c | 3443 | string ops by remembering string lengths pointed by pointer SSA_NAMEs. */ |
8b57bfeb | 3444 | |
3daacdcd | 3445 | edge |
4d9192b5 | 3446 | strlen_dom_walker::before_dom_children (basic_block bb) |
8b57bfeb | 3447 | { |
8b57bfeb JJ |
3448 | basic_block dombb = get_immediate_dominator (CDI_DOMINATORS, bb); |
3449 | ||
3450 | if (dombb == NULL) | |
3451 | stridx_to_strinfo = NULL; | |
3452 | else | |
3453 | { | |
526ceb68 | 3454 | stridx_to_strinfo = ((vec<strinfo *, va_heap, vl_embed> *) dombb->aux); |
8b57bfeb JJ |
3455 | if (stridx_to_strinfo) |
3456 | { | |
538dd0b7 DM |
3457 | for (gphi_iterator gsi = gsi_start_phis (bb); !gsi_end_p (gsi); |
3458 | gsi_next (&gsi)) | |
8b57bfeb | 3459 | { |
538dd0b7 | 3460 | gphi *phi = gsi.phi (); |
ea057359 | 3461 | if (virtual_operand_p (gimple_phi_result (phi))) |
8b57bfeb JJ |
3462 | { |
3463 | bitmap visited = BITMAP_ALLOC (NULL); | |
3464 | int count_vdef = 100; | |
3465 | do_invalidate (dombb, phi, visited, &count_vdef); | |
3466 | BITMAP_FREE (visited); | |
8b29fd4e JJ |
3467 | if (count_vdef == 0) |
3468 | { | |
3469 | /* If there were too many vdefs in between immediate | |
3470 | dominator and current bb, invalidate everything. | |
3471 | If stridx_to_strinfo has been unshared, we need | |
3472 | to free it, otherwise just set it to NULL. */ | |
3473 | if (!strinfo_shared ()) | |
3474 | { | |
3475 | unsigned int i; | |
526ceb68 | 3476 | strinfo *si; |
8b29fd4e JJ |
3477 | |
3478 | for (i = 1; | |
3479 | vec_safe_iterate (stridx_to_strinfo, i, &si); | |
3480 | ++i) | |
3481 | { | |
3482 | free_strinfo (si); | |
3483 | (*stridx_to_strinfo)[i] = NULL; | |
3484 | } | |
3485 | } | |
3486 | else | |
3487 | stridx_to_strinfo = NULL; | |
3488 | } | |
8b57bfeb JJ |
3489 | break; |
3490 | } | |
3491 | } | |
3492 | } | |
3493 | } | |
3494 | ||
3495 | /* If all PHI arguments have the same string index, the PHI result | |
3496 | has it as well. */ | |
538dd0b7 DM |
3497 | for (gphi_iterator gsi = gsi_start_phis (bb); !gsi_end_p (gsi); |
3498 | gsi_next (&gsi)) | |
8b57bfeb | 3499 | { |
538dd0b7 | 3500 | gphi *phi = gsi.phi (); |
8b57bfeb | 3501 | tree result = gimple_phi_result (phi); |
ea057359 | 3502 | if (!virtual_operand_p (result) && POINTER_TYPE_P (TREE_TYPE (result))) |
8b57bfeb JJ |
3503 | { |
3504 | int idx = get_stridx (gimple_phi_arg_def (phi, 0)); | |
3505 | if (idx != 0) | |
3506 | { | |
3507 | unsigned int i, n = gimple_phi_num_args (phi); | |
3508 | for (i = 1; i < n; i++) | |
3509 | if (idx != get_stridx (gimple_phi_arg_def (phi, i))) | |
3510 | break; | |
3511 | if (i == n) | |
9771b263 | 3512 | ssa_ver_to_stridx[SSA_NAME_VERSION (result)] = idx; |
8b57bfeb JJ |
3513 | } |
3514 | } | |
3515 | } | |
3516 | ||
fa9544ab ML |
3517 | bool cleanup_eh = false; |
3518 | ||
8b57bfeb | 3519 | /* Attempt to optimize individual statements. */ |
538dd0b7 | 3520 | for (gimple_stmt_iterator gsi = gsi_start_bb (bb); !gsi_end_p (gsi); ) |
fa9544ab | 3521 | if (strlen_check_and_optimize_stmt (&gsi, &cleanup_eh)) |
8b57bfeb JJ |
3522 | gsi_next (&gsi); |
3523 | ||
fa9544ab ML |
3524 | if (cleanup_eh && gimple_purge_dead_eh_edges (bb)) |
3525 | m_cleanup_cfg = true; | |
3526 | ||
8b57bfeb | 3527 | bb->aux = stridx_to_strinfo; |
9771b263 | 3528 | if (vec_safe_length (stridx_to_strinfo) && !strinfo_shared ()) |
526ceb68 | 3529 | (*stridx_to_strinfo)[0] = (strinfo *) bb; |
3daacdcd | 3530 | return NULL; |
8b57bfeb JJ |
3531 | } |
3532 | ||
3533 | /* Callback for walk_dominator_tree. Free strinfo vector if it is | |
3534 | owned by the current bb, clear bb->aux. */ | |
3535 | ||
4d9192b5 TS |
3536 | void |
3537 | strlen_dom_walker::after_dom_children (basic_block bb) | |
8b57bfeb JJ |
3538 | { |
3539 | if (bb->aux) | |
3540 | { | |
526ceb68 | 3541 | stridx_to_strinfo = ((vec<strinfo *, va_heap, vl_embed> *) bb->aux); |
9771b263 | 3542 | if (vec_safe_length (stridx_to_strinfo) |
526ceb68 | 3543 | && (*stridx_to_strinfo)[0] == (strinfo *) bb) |
8b57bfeb JJ |
3544 | { |
3545 | unsigned int i; | |
526ceb68 | 3546 | strinfo *si; |
8b57bfeb | 3547 | |
9771b263 | 3548 | for (i = 1; vec_safe_iterate (stridx_to_strinfo, i, &si); ++i) |
8b57bfeb | 3549 | free_strinfo (si); |
9771b263 | 3550 | vec_free (stridx_to_strinfo); |
8b57bfeb JJ |
3551 | } |
3552 | bb->aux = NULL; | |
3553 | } | |
3554 | } | |
3555 | ||
3556 | /* Main entry point. */ | |
3557 | ||
27a4cd48 DM |
3558 | namespace { |
3559 | ||
3560 | const pass_data pass_data_strlen = | |
8b57bfeb | 3561 | { |
27a4cd48 DM |
3562 | GIMPLE_PASS, /* type */ |
3563 | "strlen", /* name */ | |
3564 | OPTGROUP_NONE, /* optinfo_flags */ | |
27a4cd48 DM |
3565 | TV_TREE_STRLEN, /* tv_id */ |
3566 | ( PROP_cfg | PROP_ssa ), /* properties_required */ | |
3567 | 0, /* properties_provided */ | |
3568 | 0, /* properties_destroyed */ | |
3569 | 0, /* todo_flags_start */ | |
3bea341f | 3570 | 0, /* todo_flags_finish */ |
8b57bfeb | 3571 | }; |
27a4cd48 DM |
3572 | |
3573 | class pass_strlen : public gimple_opt_pass | |
3574 | { | |
3575 | public: | |
c3284718 RS |
3576 | pass_strlen (gcc::context *ctxt) |
3577 | : gimple_opt_pass (pass_data_strlen, ctxt) | |
27a4cd48 DM |
3578 | {} |
3579 | ||
3580 | /* opt_pass methods: */ | |
1a3d085c | 3581 | virtual bool gate (function *) { return flag_optimize_strlen != 0; } |
be55bfe6 | 3582 | virtual unsigned int execute (function *); |
27a4cd48 DM |
3583 | |
3584 | }; // class pass_strlen | |
3585 | ||
be55bfe6 TS |
3586 | unsigned int |
3587 | pass_strlen::execute (function *fun) | |
3588 | { | |
6a33d0ff MS |
3589 | gcc_assert (!strlen_to_stridx); |
3590 | if (warn_stringop_overflow || warn_stringop_truncation) | |
3591 | strlen_to_stridx = new hash_map<tree, stridx_strlenloc> (); | |
3592 | ||
be55bfe6 TS |
3593 | ssa_ver_to_stridx.safe_grow_cleared (num_ssa_names); |
3594 | max_stridx = 1; | |
be55bfe6 TS |
3595 | |
3596 | calculate_dominance_info (CDI_DOMINATORS); | |
3597 | ||
3598 | /* String length optimization is implemented as a walk of the dominator | |
3599 | tree and a forward walk of statements within each block. */ | |
fa9544ab ML |
3600 | strlen_dom_walker walker (CDI_DOMINATORS); |
3601 | walker.walk (fun->cfg->x_entry_block_ptr); | |
be55bfe6 TS |
3602 | |
3603 | ssa_ver_to_stridx.release (); | |
33e7d32e | 3604 | strinfo_pool.release (); |
c203e8a7 | 3605 | if (decl_to_stridxlist_htab) |
be55bfe6 TS |
3606 | { |
3607 | obstack_free (&stridx_obstack, NULL); | |
c203e8a7 TS |
3608 | delete decl_to_stridxlist_htab; |
3609 | decl_to_stridxlist_htab = NULL; | |
be55bfe6 TS |
3610 | } |
3611 | laststmt.stmt = NULL; | |
3612 | laststmt.len = NULL_TREE; | |
3613 | laststmt.stridx = 0; | |
3614 | ||
6a33d0ff MS |
3615 | if (strlen_to_stridx) |
3616 | { | |
3617 | strlen_to_stridx->empty (); | |
3618 | delete strlen_to_stridx; | |
3619 | strlen_to_stridx = NULL; | |
3620 | } | |
025d57f0 | 3621 | |
fa9544ab | 3622 | return walker.m_cleanup_cfg ? TODO_cleanup_cfg : 0; |
be55bfe6 TS |
3623 | } |
3624 | ||
27a4cd48 DM |
3625 | } // anon namespace |
3626 | ||
3627 | gimple_opt_pass * | |
3628 | make_pass_strlen (gcc::context *ctxt) | |
3629 | { | |
3630 | return new pass_strlen (ctxt); | |
3631 | } |