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4ee9c684 | 1 | /* Exception handling semantics and decomposition for trees. |
d353bf18 | 2 | Copyright (C) 2003-2015 Free Software Foundation, Inc. |
4ee9c684 | 3 | |
4 | This file is part of GCC. | |
5 | ||
6 | GCC is free software; you can redistribute it and/or modify | |
7 | it under the terms of the GNU General Public License as published by | |
8c4c00c1 | 8 | the Free Software Foundation; either version 3, or (at your option) |
4ee9c684 | 9 | any later version. |
10 | ||
11 | GCC is distributed in the hope that it will be useful, | |
12 | but WITHOUT ANY WARRANTY; without even the implied warranty of | |
13 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
14 | GNU General Public License for more details. | |
15 | ||
16 | You should have received a copy of the GNU General Public License | |
8c4c00c1 | 17 | along with GCC; see the file COPYING3. If not see |
18 | <http://www.gnu.org/licenses/>. */ | |
4ee9c684 | 19 | |
20 | #include "config.h" | |
21 | #include "system.h" | |
22 | #include "coretypes.h" | |
23 | #include "tm.h" | |
b20a8bb4 | 24 | #include "alias.h" |
25 | #include "symtab.h" | |
4ee9c684 | 26 | #include "tree.h" |
b20a8bb4 | 27 | #include "fold-const.h" |
a3020f2f | 28 | #include "hard-reg-set.h" |
4ee9c684 | 29 | #include "function.h" |
d53441c8 | 30 | #include "rtl.h" |
31 | #include "flags.h" | |
d53441c8 | 32 | #include "insn-config.h" |
33 | #include "expmed.h" | |
34 | #include "dojump.h" | |
35 | #include "explow.h" | |
36 | #include "calls.h" | |
37 | #include "emit-rtl.h" | |
38 | #include "varasm.h" | |
39 | #include "stmt.h" | |
40 | #include "expr.h" | |
4ee9c684 | 41 | #include "except.h" |
94ea8568 | 42 | #include "predict.h" |
43 | #include "dominance.h" | |
44 | #include "cfg.h" | |
45 | #include "cfganal.h" | |
46 | #include "cfgcleanup.h" | |
bc61cadb | 47 | #include "basic-block.h" |
48 | #include "tree-ssa-alias.h" | |
49 | #include "internal-fn.h" | |
50 | #include "tree-eh.h" | |
51 | #include "gimple-expr.h" | |
073c1fd5 | 52 | #include "gimple.h" |
dcf1a1ec | 53 | #include "gimple-iterator.h" |
073c1fd5 | 54 | #include "gimple-ssa.h" |
55 | #include "cgraph.h" | |
56 | #include "tree-cfg.h" | |
57 | #include "tree-phinodes.h" | |
58 | #include "ssa-iterators.h" | |
9ed99284 | 59 | #include "stringpool.h" |
073c1fd5 | 60 | #include "tree-ssanames.h" |
61 | #include "tree-into-ssa.h" | |
69ee5dbb | 62 | #include "tree-ssa.h" |
4ee9c684 | 63 | #include "tree-inline.h" |
4ee9c684 | 64 | #include "tree-pass.h" |
4ee9c684 | 65 | #include "langhooks.h" |
0b205f4c | 66 | #include "diagnostic-core.h" |
e38def9c | 67 | #include "target.h" |
79f958cb | 68 | #include "cfgloop.h" |
424a4a92 | 69 | #include "gimple-low.h" |
75a70cf9 | 70 | |
71 | /* In some instances a tree and a gimple need to be stored in a same table, | |
72 | i.e. in hash tables. This is a structure to do this. */ | |
73 | typedef union {tree *tp; tree t; gimple g;} treemple; | |
4ee9c684 | 74 | |
4ee9c684 | 75 | /* Misc functions used in this file. */ |
76 | ||
e38def9c | 77 | /* Remember and lookup EH landing pad data for arbitrary statements. |
4ee9c684 | 78 | Really this means any statement that could_throw_p. We could |
79 | stuff this information into the stmt_ann data structure, but: | |
80 | ||
81 | (1) We absolutely rely on this information being kept until | |
82 | we get to rtl. Once we're done with lowering here, if we lose | |
83 | the information there's no way to recover it! | |
84 | ||
ac13e8d9 | 85 | (2) There are many more statements that *cannot* throw as |
4ee9c684 | 86 | compared to those that can. We should be saving some amount |
87 | of space by only allocating memory for those that can throw. */ | |
88 | ||
e38def9c | 89 | /* Add statement T in function IFUN to landing pad NUM. */ |
75a70cf9 | 90 | |
4e57e76d | 91 | static void |
e38def9c | 92 | add_stmt_to_eh_lp_fn (struct function *ifun, gimple t, int num) |
4ee9c684 | 93 | { |
e38def9c | 94 | gcc_assert (num != 0); |
4ee9c684 | 95 | |
0de999f1 | 96 | if (!get_eh_throw_stmt_table (ifun)) |
8f359205 | 97 | set_eh_throw_stmt_table (ifun, hash_map<gimple, int>::create_ggc (31)); |
0de999f1 | 98 | |
8f359205 | 99 | gcc_assert (!get_eh_throw_stmt_table (ifun)->put (t, num)); |
4ee9c684 | 100 | } |
35c15734 | 101 | |
e38def9c | 102 | /* Add statement T in the current function (cfun) to EH landing pad NUM. */ |
75a70cf9 | 103 | |
b3f1469f | 104 | void |
e38def9c | 105 | add_stmt_to_eh_lp (gimple t, int num) |
b3f1469f | 106 | { |
e38def9c | 107 | add_stmt_to_eh_lp_fn (cfun, t, num); |
108 | } | |
109 | ||
110 | /* Add statement T to the single EH landing pad in REGION. */ | |
111 | ||
112 | static void | |
113 | record_stmt_eh_region (eh_region region, gimple t) | |
114 | { | |
115 | if (region == NULL) | |
116 | return; | |
117 | if (region->type == ERT_MUST_NOT_THROW) | |
118 | add_stmt_to_eh_lp_fn (cfun, t, -region->index); | |
119 | else | |
120 | { | |
121 | eh_landing_pad lp = region->landing_pads; | |
122 | if (lp == NULL) | |
123 | lp = gen_eh_landing_pad (region); | |
124 | else | |
125 | gcc_assert (lp->next_lp == NULL); | |
126 | add_stmt_to_eh_lp_fn (cfun, t, lp->index); | |
127 | } | |
b3f1469f | 128 | } |
129 | ||
75a70cf9 | 130 | |
e38def9c | 131 | /* Remove statement T in function IFUN from its EH landing pad. */ |
75a70cf9 | 132 | |
35c15734 | 133 | bool |
e38def9c | 134 | remove_stmt_from_eh_lp_fn (struct function *ifun, gimple t) |
35c15734 | 135 | { |
b3f1469f | 136 | if (!get_eh_throw_stmt_table (ifun)) |
35c15734 | 137 | return false; |
138 | ||
8f359205 | 139 | if (!get_eh_throw_stmt_table (ifun)->get (t)) |
35c15734 | 140 | return false; |
8f359205 | 141 | |
142 | get_eh_throw_stmt_table (ifun)->remove (t); | |
143 | return true; | |
35c15734 | 144 | } |
145 | ||
75a70cf9 | 146 | |
e38def9c | 147 | /* Remove statement T in the current function (cfun) from its |
148 | EH landing pad. */ | |
75a70cf9 | 149 | |
b3f1469f | 150 | bool |
e38def9c | 151 | remove_stmt_from_eh_lp (gimple t) |
b3f1469f | 152 | { |
e38def9c | 153 | return remove_stmt_from_eh_lp_fn (cfun, t); |
b3f1469f | 154 | } |
155 | ||
75a70cf9 | 156 | /* Determine if statement T is inside an EH region in function IFUN. |
e38def9c | 157 | Positive numbers indicate a landing pad index; negative numbers |
158 | indicate a MUST_NOT_THROW region index; zero indicates that the | |
159 | statement is not recorded in the region table. */ | |
75a70cf9 | 160 | |
4ee9c684 | 161 | int |
e38def9c | 162 | lookup_stmt_eh_lp_fn (struct function *ifun, gimple t) |
4ee9c684 | 163 | { |
e38def9c | 164 | if (ifun->eh->throw_stmt_table == NULL) |
165 | return 0; | |
4ee9c684 | 166 | |
8f359205 | 167 | int *lp_nr = ifun->eh->throw_stmt_table->get (t); |
168 | return lp_nr ? *lp_nr : 0; | |
4ee9c684 | 169 | } |
170 | ||
e38def9c | 171 | /* Likewise, but always use the current function. */ |
75a70cf9 | 172 | |
b3f1469f | 173 | int |
e38def9c | 174 | lookup_stmt_eh_lp (gimple t) |
b3f1469f | 175 | { |
176 | /* We can get called from initialized data when -fnon-call-exceptions | |
177 | is on; prevent crash. */ | |
178 | if (!cfun) | |
e38def9c | 179 | return 0; |
180 | return lookup_stmt_eh_lp_fn (cfun, t); | |
b3f1469f | 181 | } |
4ee9c684 | 182 | |
75a70cf9 | 183 | /* First pass of EH node decomposition. Build up a tree of GIMPLE_TRY_FINALLY |
4ee9c684 | 184 | nodes and LABEL_DECL nodes. We will use this during the second phase to |
185 | determine if a goto leaves the body of a TRY_FINALLY_EXPR node. */ | |
186 | ||
187 | struct finally_tree_node | |
188 | { | |
75a70cf9 | 189 | /* When storing a GIMPLE_TRY, we have to record a gimple. However |
190 | when deciding whether a GOTO to a certain LABEL_DECL (which is a | |
191 | tree) leaves the TRY block, its necessary to record a tree in | |
192 | this field. Thus a treemple is used. */ | |
e38def9c | 193 | treemple child; |
1a91d914 | 194 | gtry *parent; |
4ee9c684 | 195 | }; |
196 | ||
d9dd21a8 | 197 | /* Hashtable helpers. */ |
198 | ||
298e7f9a | 199 | struct finally_tree_hasher : free_ptr_hash <finally_tree_node> |
d9dd21a8 | 200 | { |
9969c043 | 201 | static inline hashval_t hash (const finally_tree_node *); |
202 | static inline bool equal (const finally_tree_node *, | |
203 | const finally_tree_node *); | |
d9dd21a8 | 204 | }; |
205 | ||
206 | inline hashval_t | |
9969c043 | 207 | finally_tree_hasher::hash (const finally_tree_node *v) |
d9dd21a8 | 208 | { |
209 | return (intptr_t)v->child.t >> 4; | |
210 | } | |
211 | ||
212 | inline bool | |
9969c043 | 213 | finally_tree_hasher::equal (const finally_tree_node *v, |
214 | const finally_tree_node *c) | |
d9dd21a8 | 215 | { |
216 | return v->child.t == c->child.t; | |
217 | } | |
218 | ||
4ee9c684 | 219 | /* Note that this table is *not* marked GTY. It is short-lived. */ |
c1f445d2 | 220 | static hash_table<finally_tree_hasher> *finally_tree; |
4ee9c684 | 221 | |
222 | static void | |
1a91d914 | 223 | record_in_finally_tree (treemple child, gtry *parent) |
4ee9c684 | 224 | { |
225 | struct finally_tree_node *n; | |
d9dd21a8 | 226 | finally_tree_node **slot; |
4ee9c684 | 227 | |
680a19b9 | 228 | n = XNEW (struct finally_tree_node); |
4ee9c684 | 229 | n->child = child; |
230 | n->parent = parent; | |
231 | ||
c1f445d2 | 232 | slot = finally_tree->find_slot (n, INSERT); |
8c0963c4 | 233 | gcc_assert (!*slot); |
4ee9c684 | 234 | *slot = n; |
235 | } | |
236 | ||
237 | static void | |
1a91d914 | 238 | collect_finally_tree (gimple stmt, gtry *region); |
75a70cf9 | 239 | |
e38def9c | 240 | /* Go through the gimple sequence. Works with collect_finally_tree to |
75a70cf9 | 241 | record all GIMPLE_LABEL and GIMPLE_TRY statements. */ |
242 | ||
243 | static void | |
1a91d914 | 244 | collect_finally_tree_1 (gimple_seq seq, gtry *region) |
4ee9c684 | 245 | { |
75a70cf9 | 246 | gimple_stmt_iterator gsi; |
4ee9c684 | 247 | |
75a70cf9 | 248 | for (gsi = gsi_start (seq); !gsi_end_p (gsi); gsi_next (&gsi)) |
249 | collect_finally_tree (gsi_stmt (gsi), region); | |
250 | } | |
4ee9c684 | 251 | |
75a70cf9 | 252 | static void |
1a91d914 | 253 | collect_finally_tree (gimple stmt, gtry *region) |
75a70cf9 | 254 | { |
255 | treemple temp; | |
256 | ||
257 | switch (gimple_code (stmt)) | |
258 | { | |
259 | case GIMPLE_LABEL: | |
1a91d914 | 260 | temp.t = gimple_label_label (as_a <glabel *> (stmt)); |
75a70cf9 | 261 | record_in_finally_tree (temp, region); |
262 | break; | |
4ee9c684 | 263 | |
75a70cf9 | 264 | case GIMPLE_TRY: |
265 | if (gimple_try_kind (stmt) == GIMPLE_TRY_FINALLY) | |
266 | { | |
267 | temp.g = stmt; | |
268 | record_in_finally_tree (temp, region); | |
1a91d914 | 269 | collect_finally_tree_1 (gimple_try_eval (stmt), |
270 | as_a <gtry *> (stmt)); | |
75a70cf9 | 271 | collect_finally_tree_1 (gimple_try_cleanup (stmt), region); |
272 | } | |
273 | else if (gimple_try_kind (stmt) == GIMPLE_TRY_CATCH) | |
274 | { | |
275 | collect_finally_tree_1 (gimple_try_eval (stmt), region); | |
276 | collect_finally_tree_1 (gimple_try_cleanup (stmt), region); | |
277 | } | |
278 | break; | |
4ee9c684 | 279 | |
75a70cf9 | 280 | case GIMPLE_CATCH: |
1a91d914 | 281 | collect_finally_tree_1 (gimple_catch_handler ( |
282 | as_a <gcatch *> (stmt)), | |
283 | region); | |
75a70cf9 | 284 | break; |
4ee9c684 | 285 | |
75a70cf9 | 286 | case GIMPLE_EH_FILTER: |
287 | collect_finally_tree_1 (gimple_eh_filter_failure (stmt), region); | |
4ee9c684 | 288 | break; |
289 | ||
4c0315d0 | 290 | case GIMPLE_EH_ELSE: |
1a91d914 | 291 | { |
292 | geh_else *eh_else_stmt = as_a <geh_else *> (stmt); | |
293 | collect_finally_tree_1 (gimple_eh_else_n_body (eh_else_stmt), region); | |
294 | collect_finally_tree_1 (gimple_eh_else_e_body (eh_else_stmt), region); | |
295 | } | |
4c0315d0 | 296 | break; |
297 | ||
4ee9c684 | 298 | default: |
299 | /* A type, a decl, or some kind of statement that we're not | |
300 | interested in. Don't walk them. */ | |
301 | break; | |
302 | } | |
303 | } | |
304 | ||
75a70cf9 | 305 | |
4ee9c684 | 306 | /* Use the finally tree to determine if a jump from START to TARGET |
307 | would leave the try_finally node that START lives in. */ | |
308 | ||
309 | static bool | |
75a70cf9 | 310 | outside_finally_tree (treemple start, gimple target) |
4ee9c684 | 311 | { |
312 | struct finally_tree_node n, *p; | |
313 | ||
314 | do | |
315 | { | |
316 | n.child = start; | |
c1f445d2 | 317 | p = finally_tree->find (&n); |
4ee9c684 | 318 | if (!p) |
319 | return true; | |
75a70cf9 | 320 | start.g = p->parent; |
4ee9c684 | 321 | } |
75a70cf9 | 322 | while (start.g != target); |
4ee9c684 | 323 | |
324 | return false; | |
325 | } | |
75a70cf9 | 326 | |
327 | /* Second pass of EH node decomposition. Actually transform the GIMPLE_TRY | |
328 | nodes into a set of gotos, magic labels, and eh regions. | |
4ee9c684 | 329 | The eh region creation is straight-forward, but frobbing all the gotos |
330 | and such into shape isn't. */ | |
331 | ||
48e1416a | 332 | /* The sequence into which we record all EH stuff. This will be |
e38def9c | 333 | placed at the end of the function when we're all done. */ |
334 | static gimple_seq eh_seq; | |
335 | ||
336 | /* Record whether an EH region contains something that can throw, | |
337 | indexed by EH region number. */ | |
55d6d4e4 | 338 | static bitmap eh_region_may_contain_throw_map; |
e38def9c | 339 | |
0b09525f | 340 | /* The GOTO_QUEUE is is an array of GIMPLE_GOTO and GIMPLE_RETURN |
341 | statements that are seen to escape this GIMPLE_TRY_FINALLY node. | |
342 | The idea is to record a gimple statement for everything except for | |
343 | the conditionals, which get their labels recorded. Since labels are | |
344 | of type 'tree', we need this node to store both gimple and tree | |
345 | objects. REPL_STMT is the sequence used to replace the goto/return | |
346 | statement. CONT_STMT is used to store the statement that allows | |
347 | the return/goto to jump to the original destination. */ | |
348 | ||
349 | struct goto_queue_node | |
350 | { | |
351 | treemple stmt; | |
d7ebacec | 352 | location_t location; |
0b09525f | 353 | gimple_seq repl_stmt; |
354 | gimple cont_stmt; | |
355 | int index; | |
356 | /* This is used when index >= 0 to indicate that stmt is a label (as | |
357 | opposed to a goto stmt). */ | |
358 | int is_label; | |
359 | }; | |
360 | ||
4ee9c684 | 361 | /* State of the world while lowering. */ |
362 | ||
363 | struct leh_state | |
364 | { | |
ac13e8d9 | 365 | /* What's "current" while constructing the eh region tree. These |
4ee9c684 | 366 | correspond to variables of the same name in cfun->eh, which we |
367 | don't have easy access to. */ | |
e38def9c | 368 | eh_region cur_region; |
369 | ||
370 | /* What's "current" for the purposes of __builtin_eh_pointer. For | |
371 | a CATCH, this is the associated TRY. For an EH_FILTER, this is | |
372 | the associated ALLOWED_EXCEPTIONS, etc. */ | |
373 | eh_region ehp_region; | |
4ee9c684 | 374 | |
375 | /* Processing of TRY_FINALLY requires a bit more state. This is | |
376 | split out into a separate structure so that we don't have to | |
377 | copy so much when processing other nodes. */ | |
378 | struct leh_tf_state *tf; | |
379 | }; | |
380 | ||
381 | struct leh_tf_state | |
382 | { | |
75a70cf9 | 383 | /* Pointer to the GIMPLE_TRY_FINALLY node under discussion. The |
384 | try_finally_expr is the original GIMPLE_TRY_FINALLY. We need to retain | |
385 | this so that outside_finally_tree can reliably reference the tree used | |
386 | in the collect_finally_tree data structures. */ | |
1a91d914 | 387 | gtry *try_finally_expr; |
388 | gtry *top_p; | |
e38def9c | 389 | |
75a70cf9 | 390 | /* While lowering a top_p usually it is expanded into multiple statements, |
391 | thus we need the following field to store them. */ | |
392 | gimple_seq top_p_seq; | |
4ee9c684 | 393 | |
394 | /* The state outside this try_finally node. */ | |
395 | struct leh_state *outer; | |
396 | ||
397 | /* The exception region created for it. */ | |
e38def9c | 398 | eh_region region; |
4ee9c684 | 399 | |
0b09525f | 400 | /* The goto queue. */ |
401 | struct goto_queue_node *goto_queue; | |
4ee9c684 | 402 | size_t goto_queue_size; |
403 | size_t goto_queue_active; | |
404 | ||
f0b5f617 | 405 | /* Pointer map to help in searching goto_queue when it is large. */ |
06ecf488 | 406 | hash_map<gimple, goto_queue_node *> *goto_queue_map; |
46699809 | 407 | |
4ee9c684 | 408 | /* The set of unique labels seen as entries in the goto queue. */ |
f1f41a6c | 409 | vec<tree> dest_array; |
4ee9c684 | 410 | |
411 | /* A label to be added at the end of the completed transformed | |
412 | sequence. It will be set if may_fallthru was true *at one time*, | |
413 | though subsequent transformations may have cleared that flag. */ | |
414 | tree fallthru_label; | |
415 | ||
4ee9c684 | 416 | /* True if it is possible to fall out the bottom of the try block. |
417 | Cleared if the fallthru is converted to a goto. */ | |
418 | bool may_fallthru; | |
419 | ||
75a70cf9 | 420 | /* True if any entry in goto_queue is a GIMPLE_RETURN. */ |
4ee9c684 | 421 | bool may_return; |
422 | ||
423 | /* True if the finally block can receive an exception edge. | |
424 | Cleared if the exception case is handled by code duplication. */ | |
425 | bool may_throw; | |
426 | }; | |
427 | ||
1a91d914 | 428 | static gimple_seq lower_eh_must_not_throw (struct leh_state *, gtry *); |
4ee9c684 | 429 | |
4ee9c684 | 430 | /* Search for STMT in the goto queue. Return the replacement, |
431 | or null if the statement isn't in the queue. */ | |
432 | ||
46699809 | 433 | #define LARGE_GOTO_QUEUE 20 |
434 | ||
e3a19533 | 435 | static void lower_eh_constructs_1 (struct leh_state *state, gimple_seq *seq); |
75a70cf9 | 436 | |
437 | static gimple_seq | |
438 | find_goto_replacement (struct leh_tf_state *tf, treemple stmt) | |
4ee9c684 | 439 | { |
46699809 | 440 | unsigned int i; |
46699809 | 441 | |
442 | if (tf->goto_queue_active < LARGE_GOTO_QUEUE) | |
443 | { | |
444 | for (i = 0; i < tf->goto_queue_active; i++) | |
75a70cf9 | 445 | if ( tf->goto_queue[i].stmt.g == stmt.g) |
46699809 | 446 | return tf->goto_queue[i].repl_stmt; |
447 | return NULL; | |
448 | } | |
449 | ||
450 | /* If we have a large number of entries in the goto_queue, create a | |
451 | pointer map and use that for searching. */ | |
452 | ||
453 | if (!tf->goto_queue_map) | |
454 | { | |
06ecf488 | 455 | tf->goto_queue_map = new hash_map<gimple, goto_queue_node *>; |
46699809 | 456 | for (i = 0; i < tf->goto_queue_active; i++) |
457 | { | |
06ecf488 | 458 | bool existed = tf->goto_queue_map->put (tf->goto_queue[i].stmt.g, |
459 | &tf->goto_queue[i]); | |
460 | gcc_assert (!existed); | |
46699809 | 461 | } |
462 | } | |
463 | ||
06ecf488 | 464 | goto_queue_node **slot = tf->goto_queue_map->get (stmt.g); |
46699809 | 465 | if (slot != NULL) |
06ecf488 | 466 | return ((*slot)->repl_stmt); |
46699809 | 467 | |
468 | return NULL; | |
4ee9c684 | 469 | } |
470 | ||
471 | /* A subroutine of replace_goto_queue_1. Handles the sub-clauses of a | |
75a70cf9 | 472 | lowered GIMPLE_COND. If, by chance, the replacement is a simple goto, |
4ee9c684 | 473 | then we can just splat it in, otherwise we add the new stmts immediately |
75a70cf9 | 474 | after the GIMPLE_COND and redirect. */ |
4ee9c684 | 475 | |
476 | static void | |
477 | replace_goto_queue_cond_clause (tree *tp, struct leh_tf_state *tf, | |
75a70cf9 | 478 | gimple_stmt_iterator *gsi) |
4ee9c684 | 479 | { |
75a70cf9 | 480 | tree label; |
f4e36c33 | 481 | gimple_seq new_seq; |
75a70cf9 | 482 | treemple temp; |
e60a6f7b | 483 | location_t loc = gimple_location (gsi_stmt (*gsi)); |
4ee9c684 | 484 | |
75a70cf9 | 485 | temp.tp = tp; |
f4e36c33 | 486 | new_seq = find_goto_replacement (tf, temp); |
487 | if (!new_seq) | |
4ee9c684 | 488 | return; |
489 | ||
f4e36c33 | 490 | if (gimple_seq_singleton_p (new_seq) |
491 | && gimple_code (gimple_seq_first_stmt (new_seq)) == GIMPLE_GOTO) | |
4ee9c684 | 492 | { |
f4e36c33 | 493 | *tp = gimple_goto_dest (gimple_seq_first_stmt (new_seq)); |
4ee9c684 | 494 | return; |
495 | } | |
496 | ||
e60a6f7b | 497 | label = create_artificial_label (loc); |
75a70cf9 | 498 | /* Set the new label for the GIMPLE_COND */ |
499 | *tp = label; | |
4ee9c684 | 500 | |
75a70cf9 | 501 | gsi_insert_after (gsi, gimple_build_label (label), GSI_CONTINUE_LINKING); |
f4e36c33 | 502 | gsi_insert_seq_after (gsi, gimple_seq_copy (new_seq), GSI_CONTINUE_LINKING); |
4ee9c684 | 503 | } |
504 | ||
ac13e8d9 | 505 | /* The real work of replace_goto_queue. Returns with TSI updated to |
4ee9c684 | 506 | point to the next statement. */ |
507 | ||
e3a19533 | 508 | static void replace_goto_queue_stmt_list (gimple_seq *, struct leh_tf_state *); |
4ee9c684 | 509 | |
510 | static void | |
75a70cf9 | 511 | replace_goto_queue_1 (gimple stmt, struct leh_tf_state *tf, |
512 | gimple_stmt_iterator *gsi) | |
4ee9c684 | 513 | { |
75a70cf9 | 514 | gimple_seq seq; |
515 | treemple temp; | |
516 | temp.g = NULL; | |
517 | ||
518 | switch (gimple_code (stmt)) | |
4ee9c684 | 519 | { |
75a70cf9 | 520 | case GIMPLE_GOTO: |
521 | case GIMPLE_RETURN: | |
522 | temp.g = stmt; | |
523 | seq = find_goto_replacement (tf, temp); | |
524 | if (seq) | |
4ee9c684 | 525 | { |
75a70cf9 | 526 | gsi_insert_seq_before (gsi, gimple_seq_copy (seq), GSI_SAME_STMT); |
527 | gsi_remove (gsi, false); | |
4ee9c684 | 528 | return; |
529 | } | |
530 | break; | |
531 | ||
75a70cf9 | 532 | case GIMPLE_COND: |
533 | replace_goto_queue_cond_clause (gimple_op_ptr (stmt, 2), tf, gsi); | |
534 | replace_goto_queue_cond_clause (gimple_op_ptr (stmt, 3), tf, gsi); | |
4ee9c684 | 535 | break; |
536 | ||
75a70cf9 | 537 | case GIMPLE_TRY: |
e3a19533 | 538 | replace_goto_queue_stmt_list (gimple_try_eval_ptr (stmt), tf); |
539 | replace_goto_queue_stmt_list (gimple_try_cleanup_ptr (stmt), tf); | |
4ee9c684 | 540 | break; |
75a70cf9 | 541 | case GIMPLE_CATCH: |
1a91d914 | 542 | replace_goto_queue_stmt_list (gimple_catch_handler_ptr ( |
543 | as_a <gcatch *> (stmt)), | |
544 | tf); | |
4ee9c684 | 545 | break; |
75a70cf9 | 546 | case GIMPLE_EH_FILTER: |
e3a19533 | 547 | replace_goto_queue_stmt_list (gimple_eh_filter_failure_ptr (stmt), tf); |
4ee9c684 | 548 | break; |
4c0315d0 | 549 | case GIMPLE_EH_ELSE: |
1a91d914 | 550 | { |
551 | geh_else *eh_else_stmt = as_a <geh_else *> (stmt); | |
552 | replace_goto_queue_stmt_list (gimple_eh_else_n_body_ptr (eh_else_stmt), | |
553 | tf); | |
554 | replace_goto_queue_stmt_list (gimple_eh_else_e_body_ptr (eh_else_stmt), | |
555 | tf); | |
556 | } | |
4c0315d0 | 557 | break; |
4ee9c684 | 558 | |
4ee9c684 | 559 | default: |
560 | /* These won't have gotos in them. */ | |
561 | break; | |
562 | } | |
563 | ||
75a70cf9 | 564 | gsi_next (gsi); |
4ee9c684 | 565 | } |
566 | ||
75a70cf9 | 567 | /* A subroutine of replace_goto_queue. Handles GIMPLE_SEQ. */ |
4ee9c684 | 568 | |
569 | static void | |
e3a19533 | 570 | replace_goto_queue_stmt_list (gimple_seq *seq, struct leh_tf_state *tf) |
4ee9c684 | 571 | { |
e3a19533 | 572 | gimple_stmt_iterator gsi = gsi_start (*seq); |
75a70cf9 | 573 | |
574 | while (!gsi_end_p (gsi)) | |
575 | replace_goto_queue_1 (gsi_stmt (gsi), tf, &gsi); | |
4ee9c684 | 576 | } |
577 | ||
578 | /* Replace all goto queue members. */ | |
579 | ||
580 | static void | |
581 | replace_goto_queue (struct leh_tf_state *tf) | |
582 | { | |
82a8c0dd | 583 | if (tf->goto_queue_active == 0) |
584 | return; | |
e3a19533 | 585 | replace_goto_queue_stmt_list (&tf->top_p_seq, tf); |
586 | replace_goto_queue_stmt_list (&eh_seq, tf); | |
4ee9c684 | 587 | } |
588 | ||
75a70cf9 | 589 | /* Add a new record to the goto queue contained in TF. NEW_STMT is the |
590 | data to be added, IS_LABEL indicates whether NEW_STMT is a label or | |
591 | a gimple return. */ | |
4ee9c684 | 592 | |
593 | static void | |
75a70cf9 | 594 | record_in_goto_queue (struct leh_tf_state *tf, |
595 | treemple new_stmt, | |
596 | int index, | |
d7ebacec | 597 | bool is_label, |
598 | location_t location) | |
4ee9c684 | 599 | { |
4ee9c684 | 600 | size_t active, size; |
75a70cf9 | 601 | struct goto_queue_node *q; |
4ee9c684 | 602 | |
46699809 | 603 | gcc_assert (!tf->goto_queue_map); |
604 | ||
4ee9c684 | 605 | active = tf->goto_queue_active; |
606 | size = tf->goto_queue_size; | |
607 | if (active >= size) | |
608 | { | |
609 | size = (size ? size * 2 : 32); | |
610 | tf->goto_queue_size = size; | |
611 | tf->goto_queue | |
680a19b9 | 612 | = XRESIZEVEC (struct goto_queue_node, tf->goto_queue, size); |
4ee9c684 | 613 | } |
614 | ||
615 | q = &tf->goto_queue[active]; | |
616 | tf->goto_queue_active = active + 1; | |
ac13e8d9 | 617 | |
4ee9c684 | 618 | memset (q, 0, sizeof (*q)); |
75a70cf9 | 619 | q->stmt = new_stmt; |
4ee9c684 | 620 | q->index = index; |
d7ebacec | 621 | q->location = location; |
75a70cf9 | 622 | q->is_label = is_label; |
623 | } | |
624 | ||
625 | /* Record the LABEL label in the goto queue contained in TF. | |
626 | TF is not null. */ | |
627 | ||
628 | static void | |
d7ebacec | 629 | record_in_goto_queue_label (struct leh_tf_state *tf, treemple stmt, tree label, |
630 | location_t location) | |
75a70cf9 | 631 | { |
632 | int index; | |
633 | treemple temp, new_stmt; | |
634 | ||
635 | if (!label) | |
636 | return; | |
637 | ||
638 | /* Computed and non-local gotos do not get processed. Given | |
639 | their nature we can neither tell whether we've escaped the | |
640 | finally block nor redirect them if we knew. */ | |
641 | if (TREE_CODE (label) != LABEL_DECL) | |
642 | return; | |
643 | ||
644 | /* No need to record gotos that don't leave the try block. */ | |
645 | temp.t = label; | |
646 | if (!outside_finally_tree (temp, tf->try_finally_expr)) | |
647 | return; | |
648 | ||
f1f41a6c | 649 | if (! tf->dest_array.exists ()) |
75a70cf9 | 650 | { |
f1f41a6c | 651 | tf->dest_array.create (10); |
652 | tf->dest_array.quick_push (label); | |
75a70cf9 | 653 | index = 0; |
654 | } | |
655 | else | |
656 | { | |
f1f41a6c | 657 | int n = tf->dest_array.length (); |
75a70cf9 | 658 | for (index = 0; index < n; ++index) |
f1f41a6c | 659 | if (tf->dest_array[index] == label) |
75a70cf9 | 660 | break; |
661 | if (index == n) | |
f1f41a6c | 662 | tf->dest_array.safe_push (label); |
75a70cf9 | 663 | } |
664 | ||
665 | /* In the case of a GOTO we want to record the destination label, | |
666 | since with a GIMPLE_COND we have an easy access to the then/else | |
667 | labels. */ | |
668 | new_stmt = stmt; | |
d7ebacec | 669 | record_in_goto_queue (tf, new_stmt, index, true, location); |
75a70cf9 | 670 | } |
671 | ||
672 | /* For any GIMPLE_GOTO or GIMPLE_RETURN, decide whether it leaves a try_finally | |
673 | node, and if so record that fact in the goto queue associated with that | |
674 | try_finally node. */ | |
675 | ||
676 | static void | |
677 | maybe_record_in_goto_queue (struct leh_state *state, gimple stmt) | |
678 | { | |
679 | struct leh_tf_state *tf = state->tf; | |
680 | treemple new_stmt; | |
681 | ||
682 | if (!tf) | |
683 | return; | |
684 | ||
685 | switch (gimple_code (stmt)) | |
686 | { | |
687 | case GIMPLE_COND: | |
1a91d914 | 688 | { |
689 | gcond *cond_stmt = as_a <gcond *> (stmt); | |
690 | new_stmt.tp = gimple_op_ptr (cond_stmt, 2); | |
691 | record_in_goto_queue_label (tf, new_stmt, | |
692 | gimple_cond_true_label (cond_stmt), | |
693 | EXPR_LOCATION (*new_stmt.tp)); | |
694 | new_stmt.tp = gimple_op_ptr (cond_stmt, 3); | |
695 | record_in_goto_queue_label (tf, new_stmt, | |
696 | gimple_cond_false_label (cond_stmt), | |
697 | EXPR_LOCATION (*new_stmt.tp)); | |
698 | } | |
75a70cf9 | 699 | break; |
700 | case GIMPLE_GOTO: | |
701 | new_stmt.g = stmt; | |
d7ebacec | 702 | record_in_goto_queue_label (tf, new_stmt, gimple_goto_dest (stmt), |
703 | gimple_location (stmt)); | |
75a70cf9 | 704 | break; |
705 | ||
706 | case GIMPLE_RETURN: | |
707 | tf->may_return = true; | |
708 | new_stmt.g = stmt; | |
d7ebacec | 709 | record_in_goto_queue (tf, new_stmt, -1, false, gimple_location (stmt)); |
75a70cf9 | 710 | break; |
711 | ||
712 | default: | |
713 | gcc_unreachable (); | |
714 | } | |
4ee9c684 | 715 | } |
716 | ||
75a70cf9 | 717 | |
4ee9c684 | 718 | #ifdef ENABLE_CHECKING |
75a70cf9 | 719 | /* We do not process GIMPLE_SWITCHes for now. As long as the original source |
4ee9c684 | 720 | was in fact structured, and we've not yet done jump threading, then none |
75a70cf9 | 721 | of the labels will leave outer GIMPLE_TRY_FINALLY nodes. Verify this. */ |
4ee9c684 | 722 | |
723 | static void | |
1a91d914 | 724 | verify_norecord_switch_expr (struct leh_state *state, |
725 | gswitch *switch_expr) | |
4ee9c684 | 726 | { |
727 | struct leh_tf_state *tf = state->tf; | |
728 | size_t i, n; | |
4ee9c684 | 729 | |
730 | if (!tf) | |
731 | return; | |
732 | ||
75a70cf9 | 733 | n = gimple_switch_num_labels (switch_expr); |
4ee9c684 | 734 | |
735 | for (i = 0; i < n; ++i) | |
736 | { | |
75a70cf9 | 737 | treemple temp; |
738 | tree lab = CASE_LABEL (gimple_switch_label (switch_expr, i)); | |
739 | temp.t = lab; | |
740 | gcc_assert (!outside_finally_tree (temp, tf->try_finally_expr)); | |
4ee9c684 | 741 | } |
742 | } | |
743 | #else | |
744 | #define verify_norecord_switch_expr(state, switch_expr) | |
745 | #endif | |
746 | ||
9a14ac4f | 747 | /* Redirect a RETURN_EXPR pointed to by Q to FINLAB. If MOD is |
748 | non-null, insert it before the new branch. */ | |
4ee9c684 | 749 | |
750 | static void | |
9a14ac4f | 751 | do_return_redirection (struct goto_queue_node *q, tree finlab, gimple_seq mod) |
4ee9c684 | 752 | { |
75a70cf9 | 753 | gimple x; |
754 | ||
9a14ac4f | 755 | /* In the case of a return, the queue node must be a gimple statement. */ |
75a70cf9 | 756 | gcc_assert (!q->is_label); |
757 | ||
9a14ac4f | 758 | /* Note that the return value may have already been computed, e.g., |
4ee9c684 | 759 | |
9a14ac4f | 760 | int x; |
761 | int foo (void) | |
4ee9c684 | 762 | { |
9a14ac4f | 763 | x = 0; |
764 | try { | |
765 | return x; | |
766 | } finally { | |
767 | x++; | |
768 | } | |
4ee9c684 | 769 | } |
9a14ac4f | 770 | |
771 | should return 0, not 1. We don't have to do anything to make | |
772 | this happens because the return value has been placed in the | |
773 | RESULT_DECL already. */ | |
774 | ||
775 | q->cont_stmt = q->stmt.g; | |
75a70cf9 | 776 | |
4ee9c684 | 777 | if (mod) |
75a70cf9 | 778 | gimple_seq_add_seq (&q->repl_stmt, mod); |
4ee9c684 | 779 | |
75a70cf9 | 780 | x = gimple_build_goto (finlab); |
ed4d69dc | 781 | gimple_set_location (x, q->location); |
75a70cf9 | 782 | gimple_seq_add_stmt (&q->repl_stmt, x); |
4ee9c684 | 783 | } |
784 | ||
75a70cf9 | 785 | /* Similar, but easier, for GIMPLE_GOTO. */ |
4ee9c684 | 786 | |
787 | static void | |
75a70cf9 | 788 | do_goto_redirection (struct goto_queue_node *q, tree finlab, gimple_seq mod, |
789 | struct leh_tf_state *tf) | |
4ee9c684 | 790 | { |
1a91d914 | 791 | ggoto *x; |
75a70cf9 | 792 | |
793 | gcc_assert (q->is_label); | |
75a70cf9 | 794 | |
f1f41a6c | 795 | q->cont_stmt = gimple_build_goto (tf->dest_array[q->index]); |
4ee9c684 | 796 | |
4ee9c684 | 797 | if (mod) |
75a70cf9 | 798 | gimple_seq_add_seq (&q->repl_stmt, mod); |
4ee9c684 | 799 | |
75a70cf9 | 800 | x = gimple_build_goto (finlab); |
ed4d69dc | 801 | gimple_set_location (x, q->location); |
75a70cf9 | 802 | gimple_seq_add_stmt (&q->repl_stmt, x); |
4ee9c684 | 803 | } |
804 | ||
e38def9c | 805 | /* Emit a standard landing pad sequence into SEQ for REGION. */ |
806 | ||
807 | static void | |
808 | emit_post_landing_pad (gimple_seq *seq, eh_region region) | |
809 | { | |
810 | eh_landing_pad lp = region->landing_pads; | |
1a91d914 | 811 | glabel *x; |
e38def9c | 812 | |
813 | if (lp == NULL) | |
814 | lp = gen_eh_landing_pad (region); | |
815 | ||
816 | lp->post_landing_pad = create_artificial_label (UNKNOWN_LOCATION); | |
817 | EH_LANDING_PAD_NR (lp->post_landing_pad) = lp->index; | |
818 | ||
819 | x = gimple_build_label (lp->post_landing_pad); | |
820 | gimple_seq_add_stmt (seq, x); | |
821 | } | |
822 | ||
823 | /* Emit a RESX statement into SEQ for REGION. */ | |
824 | ||
825 | static void | |
826 | emit_resx (gimple_seq *seq, eh_region region) | |
827 | { | |
1a91d914 | 828 | gresx *x = gimple_build_resx (region->index); |
e38def9c | 829 | gimple_seq_add_stmt (seq, x); |
830 | if (region->outer) | |
831 | record_stmt_eh_region (region->outer, x); | |
832 | } | |
833 | ||
834 | /* Emit an EH_DISPATCH statement into SEQ for REGION. */ | |
835 | ||
836 | static void | |
837 | emit_eh_dispatch (gimple_seq *seq, eh_region region) | |
838 | { | |
1a91d914 | 839 | geh_dispatch *x = gimple_build_eh_dispatch (region->index); |
e38def9c | 840 | gimple_seq_add_stmt (seq, x); |
841 | } | |
842 | ||
843 | /* Note that the current EH region may contain a throw, or a | |
844 | call to a function which itself may contain a throw. */ | |
845 | ||
846 | static void | |
847 | note_eh_region_may_contain_throw (eh_region region) | |
848 | { | |
6ef9bbe0 | 849 | while (bitmap_set_bit (eh_region_may_contain_throw_map, region->index)) |
e38def9c | 850 | { |
39efead8 | 851 | if (region->type == ERT_MUST_NOT_THROW) |
852 | break; | |
e38def9c | 853 | region = region->outer; |
854 | if (region == NULL) | |
855 | break; | |
856 | } | |
857 | } | |
858 | ||
55d6d4e4 | 859 | /* Check if REGION has been marked as containing a throw. If REGION is |
860 | NULL, this predicate is false. */ | |
861 | ||
862 | static inline bool | |
863 | eh_region_may_contain_throw (eh_region r) | |
864 | { | |
865 | return r && bitmap_bit_p (eh_region_may_contain_throw_map, r->index); | |
866 | } | |
867 | ||
4ee9c684 | 868 | /* We want to transform |
869 | try { body; } catch { stuff; } | |
870 | to | |
4422041b | 871 | normal_sequence: |
e38def9c | 872 | body; |
873 | over: | |
4422041b | 874 | eh_sequence: |
e38def9c | 875 | landing_pad: |
876 | stuff; | |
877 | goto over; | |
878 | ||
879 | TP is a GIMPLE_TRY node. REGION is the region whose post_landing_pad | |
4ee9c684 | 880 | should be placed before the second operand, or NULL. OVER is |
881 | an existing label that should be put at the exit, or NULL. */ | |
882 | ||
75a70cf9 | 883 | static gimple_seq |
1a91d914 | 884 | frob_into_branch_around (gtry *tp, eh_region region, tree over) |
4ee9c684 | 885 | { |
75a70cf9 | 886 | gimple x; |
887 | gimple_seq cleanup, result; | |
e60a6f7b | 888 | location_t loc = gimple_location (tp); |
4ee9c684 | 889 | |
75a70cf9 | 890 | cleanup = gimple_try_cleanup (tp); |
891 | result = gimple_try_eval (tp); | |
4ee9c684 | 892 | |
e38def9c | 893 | if (region) |
894 | emit_post_landing_pad (&eh_seq, region); | |
895 | ||
896 | if (gimple_seq_may_fallthru (cleanup)) | |
4ee9c684 | 897 | { |
898 | if (!over) | |
e60a6f7b | 899 | over = create_artificial_label (loc); |
75a70cf9 | 900 | x = gimple_build_goto (over); |
ed4d69dc | 901 | gimple_set_location (x, loc); |
e38def9c | 902 | gimple_seq_add_stmt (&cleanup, x); |
4ee9c684 | 903 | } |
e38def9c | 904 | gimple_seq_add_seq (&eh_seq, cleanup); |
4ee9c684 | 905 | |
906 | if (over) | |
907 | { | |
75a70cf9 | 908 | x = gimple_build_label (over); |
909 | gimple_seq_add_stmt (&result, x); | |
4ee9c684 | 910 | } |
75a70cf9 | 911 | return result; |
4ee9c684 | 912 | } |
913 | ||
914 | /* A subroutine of lower_try_finally. Duplicate the tree rooted at T. | |
915 | Make sure to record all new labels found. */ | |
916 | ||
75a70cf9 | 917 | static gimple_seq |
d7ebacec | 918 | lower_try_finally_dup_block (gimple_seq seq, struct leh_state *outer_state, |
919 | location_t loc) | |
4ee9c684 | 920 | { |
1a91d914 | 921 | gtry *region = NULL; |
75a70cf9 | 922 | gimple_seq new_seq; |
d7ebacec | 923 | gimple_stmt_iterator gsi; |
4ee9c684 | 924 | |
75a70cf9 | 925 | new_seq = copy_gimple_seq_and_replace_locals (seq); |
4ee9c684 | 926 | |
d7ebacec | 927 | for (gsi = gsi_start (new_seq); !gsi_end_p (gsi); gsi_next (&gsi)) |
cc9f317f | 928 | { |
929 | gimple stmt = gsi_stmt (gsi); | |
8e7408e3 | 930 | if (LOCATION_LOCUS (gimple_location (stmt)) == UNKNOWN_LOCATION) |
cc9f317f | 931 | { |
932 | tree block = gimple_block (stmt); | |
933 | gimple_set_location (stmt, loc); | |
934 | gimple_set_block (stmt, block); | |
935 | } | |
936 | } | |
d7ebacec | 937 | |
4ee9c684 | 938 | if (outer_state->tf) |
939 | region = outer_state->tf->try_finally_expr; | |
75a70cf9 | 940 | collect_finally_tree_1 (new_seq, region); |
4ee9c684 | 941 | |
75a70cf9 | 942 | return new_seq; |
4ee9c684 | 943 | } |
944 | ||
945 | /* A subroutine of lower_try_finally. Create a fallthru label for | |
946 | the given try_finally state. The only tricky bit here is that | |
947 | we have to make sure to record the label in our outer context. */ | |
948 | ||
949 | static tree | |
950 | lower_try_finally_fallthru_label (struct leh_tf_state *tf) | |
951 | { | |
952 | tree label = tf->fallthru_label; | |
75a70cf9 | 953 | treemple temp; |
954 | ||
4ee9c684 | 955 | if (!label) |
956 | { | |
e60a6f7b | 957 | label = create_artificial_label (gimple_location (tf->try_finally_expr)); |
4ee9c684 | 958 | tf->fallthru_label = label; |
959 | if (tf->outer->tf) | |
75a70cf9 | 960 | { |
961 | temp.t = label; | |
962 | record_in_finally_tree (temp, tf->outer->tf->try_finally_expr); | |
963 | } | |
4ee9c684 | 964 | } |
965 | return label; | |
966 | } | |
967 | ||
4c0315d0 | 968 | /* A subroutine of lower_try_finally. If FINALLY consits of a |
969 | GIMPLE_EH_ELSE node, return it. */ | |
970 | ||
1a91d914 | 971 | static inline geh_else * |
4c0315d0 | 972 | get_eh_else (gimple_seq finally) |
973 | { | |
974 | gimple x = gimple_seq_first_stmt (finally); | |
975 | if (gimple_code (x) == GIMPLE_EH_ELSE) | |
976 | { | |
977 | gcc_assert (gimple_seq_singleton_p (finally)); | |
1a91d914 | 978 | return as_a <geh_else *> (x); |
4c0315d0 | 979 | } |
980 | return NULL; | |
981 | } | |
982 | ||
596981c8 | 983 | /* A subroutine of lower_try_finally. If the eh_protect_cleanup_actions |
984 | langhook returns non-null, then the language requires that the exception | |
985 | path out of a try_finally be treated specially. To wit: the code within | |
986 | the finally block may not itself throw an exception. We have two choices | |
987 | here. First we can duplicate the finally block and wrap it in a | |
988 | must_not_throw region. Second, we can generate code like | |
4ee9c684 | 989 | |
990 | try { | |
991 | finally_block; | |
992 | } catch { | |
993 | if (fintmp == eh_edge) | |
994 | protect_cleanup_actions; | |
995 | } | |
996 | ||
997 | where "fintmp" is the temporary used in the switch statement generation | |
998 | alternative considered below. For the nonce, we always choose the first | |
ac13e8d9 | 999 | option. |
4ee9c684 | 1000 | |
822e391f | 1001 | THIS_STATE may be null if this is a try-cleanup, not a try-finally. */ |
4ee9c684 | 1002 | |
1003 | static void | |
1004 | honor_protect_cleanup_actions (struct leh_state *outer_state, | |
1005 | struct leh_state *this_state, | |
1006 | struct leh_tf_state *tf) | |
1007 | { | |
e38def9c | 1008 | tree protect_cleanup_actions; |
75a70cf9 | 1009 | gimple_stmt_iterator gsi; |
4ee9c684 | 1010 | bool finally_may_fallthru; |
75a70cf9 | 1011 | gimple_seq finally; |
1a91d914 | 1012 | gimple x; |
1013 | geh_mnt *eh_mnt; | |
1014 | gtry *try_stmt; | |
1015 | geh_else *eh_else; | |
4ee9c684 | 1016 | |
1017 | /* First check for nothing to do. */ | |
596981c8 | 1018 | if (lang_hooks.eh_protect_cleanup_actions == NULL) |
e38def9c | 1019 | return; |
596981c8 | 1020 | protect_cleanup_actions = lang_hooks.eh_protect_cleanup_actions (); |
e38def9c | 1021 | if (protect_cleanup_actions == NULL) |
1022 | return; | |
4ee9c684 | 1023 | |
75a70cf9 | 1024 | finally = gimple_try_cleanup (tf->top_p); |
4c0315d0 | 1025 | eh_else = get_eh_else (finally); |
4ee9c684 | 1026 | |
1027 | /* Duplicate the FINALLY block. Only need to do this for try-finally, | |
4c0315d0 | 1028 | and not for cleanups. If we've got an EH_ELSE, extract it now. */ |
1029 | if (eh_else) | |
1030 | { | |
1031 | finally = gimple_eh_else_e_body (eh_else); | |
1032 | gimple_try_set_cleanup (tf->top_p, gimple_eh_else_n_body (eh_else)); | |
1033 | } | |
1034 | else if (this_state) | |
d7ebacec | 1035 | finally = lower_try_finally_dup_block (finally, outer_state, |
5169661d | 1036 | gimple_location (tf->try_finally_expr)); |
4c0315d0 | 1037 | finally_may_fallthru = gimple_seq_may_fallthru (finally); |
4ee9c684 | 1038 | |
0bc060a4 | 1039 | /* If this cleanup consists of a TRY_CATCH_EXPR with TRY_CATCH_IS_CLEANUP |
1040 | set, the handler of the TRY_CATCH_EXPR is another cleanup which ought | |
1041 | to be in an enclosing scope, but needs to be implemented at this level | |
1042 | to avoid a nesting violation (see wrap_temporary_cleanups in | |
1043 | cp/decl.c). Since it's logically at an outer level, we should call | |
1044 | terminate before we get to it, so strip it away before adding the | |
1045 | MUST_NOT_THROW filter. */ | |
75a70cf9 | 1046 | gsi = gsi_start (finally); |
1047 | x = gsi_stmt (gsi); | |
e38def9c | 1048 | if (gimple_code (x) == GIMPLE_TRY |
75a70cf9 | 1049 | && gimple_try_kind (x) == GIMPLE_TRY_CATCH |
1050 | && gimple_try_catch_is_cleanup (x)) | |
0bc060a4 | 1051 | { |
75a70cf9 | 1052 | gsi_insert_seq_before (&gsi, gimple_try_eval (x), GSI_SAME_STMT); |
1053 | gsi_remove (&gsi, false); | |
0bc060a4 | 1054 | } |
1055 | ||
4ee9c684 | 1056 | /* Wrap the block with protect_cleanup_actions as the action. */ |
1a91d914 | 1057 | eh_mnt = gimple_build_eh_must_not_throw (protect_cleanup_actions); |
1058 | try_stmt = gimple_build_try (finally, gimple_seq_alloc_with_stmt (eh_mnt), | |
1059 | GIMPLE_TRY_CATCH); | |
1060 | finally = lower_eh_must_not_throw (outer_state, try_stmt); | |
e38def9c | 1061 | |
1062 | /* Drop all of this into the exception sequence. */ | |
1063 | emit_post_landing_pad (&eh_seq, tf->region); | |
1064 | gimple_seq_add_seq (&eh_seq, finally); | |
1065 | if (finally_may_fallthru) | |
1066 | emit_resx (&eh_seq, tf->region); | |
4ee9c684 | 1067 | |
1068 | /* Having now been handled, EH isn't to be considered with | |
1069 | the rest of the outgoing edges. */ | |
1070 | tf->may_throw = false; | |
1071 | } | |
1072 | ||
1073 | /* A subroutine of lower_try_finally. We have determined that there is | |
1074 | no fallthru edge out of the finally block. This means that there is | |
1075 | no outgoing edge corresponding to any incoming edge. Restructure the | |
1076 | try_finally node for this special case. */ | |
1077 | ||
1078 | static void | |
75a70cf9 | 1079 | lower_try_finally_nofallthru (struct leh_state *state, |
1080 | struct leh_tf_state *tf) | |
4ee9c684 | 1081 | { |
9a14ac4f | 1082 | tree lab; |
1a91d914 | 1083 | gimple x; |
1084 | geh_else *eh_else; | |
75a70cf9 | 1085 | gimple_seq finally; |
4ee9c684 | 1086 | struct goto_queue_node *q, *qe; |
1087 | ||
e38def9c | 1088 | lab = create_artificial_label (gimple_location (tf->try_finally_expr)); |
4ee9c684 | 1089 | |
75a70cf9 | 1090 | /* We expect that tf->top_p is a GIMPLE_TRY. */ |
1091 | finally = gimple_try_cleanup (tf->top_p); | |
1092 | tf->top_p_seq = gimple_try_eval (tf->top_p); | |
4ee9c684 | 1093 | |
75a70cf9 | 1094 | x = gimple_build_label (lab); |
1095 | gimple_seq_add_stmt (&tf->top_p_seq, x); | |
4ee9c684 | 1096 | |
4ee9c684 | 1097 | q = tf->goto_queue; |
1098 | qe = q + tf->goto_queue_active; | |
1099 | for (; q < qe; ++q) | |
1100 | if (q->index < 0) | |
9a14ac4f | 1101 | do_return_redirection (q, lab, NULL); |
4ee9c684 | 1102 | else |
75a70cf9 | 1103 | do_goto_redirection (q, lab, NULL, tf); |
4ee9c684 | 1104 | |
1105 | replace_goto_queue (tf); | |
1106 | ||
4c0315d0 | 1107 | /* Emit the finally block into the stream. Lower EH_ELSE at this time. */ |
1108 | eh_else = get_eh_else (finally); | |
1109 | if (eh_else) | |
1110 | { | |
1111 | finally = gimple_eh_else_n_body (eh_else); | |
e3a19533 | 1112 | lower_eh_constructs_1 (state, &finally); |
4c0315d0 | 1113 | gimple_seq_add_seq (&tf->top_p_seq, finally); |
e38def9c | 1114 | |
4c0315d0 | 1115 | if (tf->may_throw) |
1116 | { | |
1117 | finally = gimple_eh_else_e_body (eh_else); | |
e3a19533 | 1118 | lower_eh_constructs_1 (state, &finally); |
4c0315d0 | 1119 | |
1120 | emit_post_landing_pad (&eh_seq, tf->region); | |
1121 | gimple_seq_add_seq (&eh_seq, finally); | |
1122 | } | |
1123 | } | |
1124 | else | |
e38def9c | 1125 | { |
e3a19533 | 1126 | lower_eh_constructs_1 (state, &finally); |
4c0315d0 | 1127 | gimple_seq_add_seq (&tf->top_p_seq, finally); |
e38def9c | 1128 | |
4c0315d0 | 1129 | if (tf->may_throw) |
1130 | { | |
1131 | emit_post_landing_pad (&eh_seq, tf->region); | |
1132 | ||
1133 | x = gimple_build_goto (lab); | |
ed4d69dc | 1134 | gimple_set_location (x, gimple_location (tf->try_finally_expr)); |
4c0315d0 | 1135 | gimple_seq_add_stmt (&eh_seq, x); |
1136 | } | |
e38def9c | 1137 | } |
4ee9c684 | 1138 | } |
1139 | ||
1140 | /* A subroutine of lower_try_finally. We have determined that there is | |
1141 | exactly one destination of the finally block. Restructure the | |
1142 | try_finally node for this special case. */ | |
1143 | ||
1144 | static void | |
1145 | lower_try_finally_onedest (struct leh_state *state, struct leh_tf_state *tf) | |
1146 | { | |
1147 | struct goto_queue_node *q, *qe; | |
1a91d914 | 1148 | geh_else *eh_else; |
1149 | glabel *label_stmt; | |
75a70cf9 | 1150 | gimple x; |
1151 | gimple_seq finally; | |
ae117ec5 | 1152 | gimple_stmt_iterator gsi; |
75a70cf9 | 1153 | tree finally_label; |
e60a6f7b | 1154 | location_t loc = gimple_location (tf->try_finally_expr); |
4ee9c684 | 1155 | |
75a70cf9 | 1156 | finally = gimple_try_cleanup (tf->top_p); |
1157 | tf->top_p_seq = gimple_try_eval (tf->top_p); | |
4ee9c684 | 1158 | |
4c0315d0 | 1159 | /* Since there's only one destination, and the destination edge can only |
1160 | either be EH or non-EH, that implies that all of our incoming edges | |
1161 | are of the same type. Therefore we can lower EH_ELSE immediately. */ | |
1a91d914 | 1162 | eh_else = get_eh_else (finally); |
1163 | if (eh_else) | |
4c0315d0 | 1164 | { |
1165 | if (tf->may_throw) | |
1a91d914 | 1166 | finally = gimple_eh_else_e_body (eh_else); |
4c0315d0 | 1167 | else |
1a91d914 | 1168 | finally = gimple_eh_else_n_body (eh_else); |
4c0315d0 | 1169 | } |
1170 | ||
e3a19533 | 1171 | lower_eh_constructs_1 (state, &finally); |
4ee9c684 | 1172 | |
ae117ec5 | 1173 | for (gsi = gsi_start (finally); !gsi_end_p (gsi); gsi_next (&gsi)) |
1174 | { | |
1175 | gimple stmt = gsi_stmt (gsi); | |
1176 | if (LOCATION_LOCUS (gimple_location (stmt)) == UNKNOWN_LOCATION) | |
1177 | { | |
1178 | tree block = gimple_block (stmt); | |
1179 | gimple_set_location (stmt, gimple_location (tf->try_finally_expr)); | |
1180 | gimple_set_block (stmt, block); | |
1181 | } | |
1182 | } | |
1183 | ||
4ee9c684 | 1184 | if (tf->may_throw) |
1185 | { | |
1186 | /* Only reachable via the exception edge. Add the given label to | |
1187 | the head of the FINALLY block. Append a RESX at the end. */ | |
e38def9c | 1188 | emit_post_landing_pad (&eh_seq, tf->region); |
1189 | gimple_seq_add_seq (&eh_seq, finally); | |
1190 | emit_resx (&eh_seq, tf->region); | |
4ee9c684 | 1191 | return; |
1192 | } | |
1193 | ||
1194 | if (tf->may_fallthru) | |
1195 | { | |
1196 | /* Only reachable via the fallthru edge. Do nothing but let | |
1197 | the two blocks run together; we'll fall out the bottom. */ | |
75a70cf9 | 1198 | gimple_seq_add_seq (&tf->top_p_seq, finally); |
4ee9c684 | 1199 | return; |
1200 | } | |
1201 | ||
e60a6f7b | 1202 | finally_label = create_artificial_label (loc); |
1a91d914 | 1203 | label_stmt = gimple_build_label (finally_label); |
1204 | gimple_seq_add_stmt (&tf->top_p_seq, label_stmt); | |
4ee9c684 | 1205 | |
75a70cf9 | 1206 | gimple_seq_add_seq (&tf->top_p_seq, finally); |
4ee9c684 | 1207 | |
1208 | q = tf->goto_queue; | |
1209 | qe = q + tf->goto_queue_active; | |
1210 | ||
1211 | if (tf->may_return) | |
1212 | { | |
1213 | /* Reachable by return expressions only. Redirect them. */ | |
4ee9c684 | 1214 | for (; q < qe; ++q) |
9a14ac4f | 1215 | do_return_redirection (q, finally_label, NULL); |
4ee9c684 | 1216 | replace_goto_queue (tf); |
1217 | } | |
1218 | else | |
1219 | { | |
1220 | /* Reachable by goto expressions only. Redirect them. */ | |
1221 | for (; q < qe; ++q) | |
75a70cf9 | 1222 | do_goto_redirection (q, finally_label, NULL, tf); |
4ee9c684 | 1223 | replace_goto_queue (tf); |
ac13e8d9 | 1224 | |
f1f41a6c | 1225 | if (tf->dest_array[0] == tf->fallthru_label) |
4ee9c684 | 1226 | { |
1227 | /* Reachable by goto to fallthru label only. Redirect it | |
1228 | to the new label (already created, sadly), and do not | |
1229 | emit the final branch out, or the fallthru label. */ | |
1230 | tf->fallthru_label = NULL; | |
1231 | return; | |
1232 | } | |
1233 | } | |
1234 | ||
75a70cf9 | 1235 | /* Place the original return/goto to the original destination |
1236 | immediately after the finally block. */ | |
1237 | x = tf->goto_queue[0].cont_stmt; | |
1238 | gimple_seq_add_stmt (&tf->top_p_seq, x); | |
1239 | maybe_record_in_goto_queue (state, x); | |
4ee9c684 | 1240 | } |
1241 | ||
1242 | /* A subroutine of lower_try_finally. There are multiple edges incoming | |
1243 | and outgoing from the finally block. Implement this by duplicating the | |
1244 | finally block for every destination. */ | |
1245 | ||
1246 | static void | |
1247 | lower_try_finally_copy (struct leh_state *state, struct leh_tf_state *tf) | |
1248 | { | |
75a70cf9 | 1249 | gimple_seq finally; |
1250 | gimple_seq new_stmt; | |
1251 | gimple_seq seq; | |
1a91d914 | 1252 | gimple x; |
1253 | geh_else *eh_else; | |
75a70cf9 | 1254 | tree tmp; |
e60a6f7b | 1255 | location_t tf_loc = gimple_location (tf->try_finally_expr); |
4ee9c684 | 1256 | |
75a70cf9 | 1257 | finally = gimple_try_cleanup (tf->top_p); |
4c0315d0 | 1258 | |
1259 | /* Notice EH_ELSE, and simplify some of the remaining code | |
1260 | by considering FINALLY to be the normal return path only. */ | |
1261 | eh_else = get_eh_else (finally); | |
1262 | if (eh_else) | |
1263 | finally = gimple_eh_else_n_body (eh_else); | |
1264 | ||
75a70cf9 | 1265 | tf->top_p_seq = gimple_try_eval (tf->top_p); |
1266 | new_stmt = NULL; | |
4ee9c684 | 1267 | |
1268 | if (tf->may_fallthru) | |
1269 | { | |
d7ebacec | 1270 | seq = lower_try_finally_dup_block (finally, state, tf_loc); |
e3a19533 | 1271 | lower_eh_constructs_1 (state, &seq); |
75a70cf9 | 1272 | gimple_seq_add_seq (&new_stmt, seq); |
4ee9c684 | 1273 | |
75a70cf9 | 1274 | tmp = lower_try_finally_fallthru_label (tf); |
1275 | x = gimple_build_goto (tmp); | |
ed4d69dc | 1276 | gimple_set_location (x, tf_loc); |
75a70cf9 | 1277 | gimple_seq_add_stmt (&new_stmt, x); |
4ee9c684 | 1278 | } |
1279 | ||
1280 | if (tf->may_throw) | |
1281 | { | |
4c0315d0 | 1282 | /* We don't need to copy the EH path of EH_ELSE, |
1283 | since it is only emitted once. */ | |
1284 | if (eh_else) | |
1285 | seq = gimple_eh_else_e_body (eh_else); | |
1286 | else | |
d7ebacec | 1287 | seq = lower_try_finally_dup_block (finally, state, tf_loc); |
e3a19533 | 1288 | lower_eh_constructs_1 (state, &seq); |
4ee9c684 | 1289 | |
2fabdfdf | 1290 | emit_post_landing_pad (&eh_seq, tf->region); |
1291 | gimple_seq_add_seq (&eh_seq, seq); | |
e38def9c | 1292 | emit_resx (&eh_seq, tf->region); |
4ee9c684 | 1293 | } |
1294 | ||
1295 | if (tf->goto_queue) | |
1296 | { | |
1297 | struct goto_queue_node *q, *qe; | |
22347b24 | 1298 | int return_index, index; |
680a19b9 | 1299 | struct labels_s |
22347b24 | 1300 | { |
1301 | struct goto_queue_node *q; | |
1302 | tree label; | |
1303 | } *labels; | |
4ee9c684 | 1304 | |
f1f41a6c | 1305 | return_index = tf->dest_array.length (); |
680a19b9 | 1306 | labels = XCNEWVEC (struct labels_s, return_index + 1); |
4ee9c684 | 1307 | |
1308 | q = tf->goto_queue; | |
1309 | qe = q + tf->goto_queue_active; | |
1310 | for (; q < qe; q++) | |
1311 | { | |
22347b24 | 1312 | index = q->index < 0 ? return_index : q->index; |
1313 | ||
1314 | if (!labels[index].q) | |
1315 | labels[index].q = q; | |
1316 | } | |
1317 | ||
1318 | for (index = 0; index < return_index + 1; index++) | |
1319 | { | |
1320 | tree lab; | |
1321 | ||
1322 | q = labels[index].q; | |
1323 | if (! q) | |
1324 | continue; | |
1325 | ||
e60a6f7b | 1326 | lab = labels[index].label |
1327 | = create_artificial_label (tf_loc); | |
4ee9c684 | 1328 | |
1329 | if (index == return_index) | |
9a14ac4f | 1330 | do_return_redirection (q, lab, NULL); |
4ee9c684 | 1331 | else |
75a70cf9 | 1332 | do_goto_redirection (q, lab, NULL, tf); |
4ee9c684 | 1333 | |
75a70cf9 | 1334 | x = gimple_build_label (lab); |
1335 | gimple_seq_add_stmt (&new_stmt, x); | |
4ee9c684 | 1336 | |
d7ebacec | 1337 | seq = lower_try_finally_dup_block (finally, state, q->location); |
e3a19533 | 1338 | lower_eh_constructs_1 (state, &seq); |
75a70cf9 | 1339 | gimple_seq_add_seq (&new_stmt, seq); |
4ee9c684 | 1340 | |
75a70cf9 | 1341 | gimple_seq_add_stmt (&new_stmt, q->cont_stmt); |
22347b24 | 1342 | maybe_record_in_goto_queue (state, q->cont_stmt); |
4ee9c684 | 1343 | } |
22347b24 | 1344 | |
1345 | for (q = tf->goto_queue; q < qe; q++) | |
1346 | { | |
1347 | tree lab; | |
1348 | ||
1349 | index = q->index < 0 ? return_index : q->index; | |
1350 | ||
1351 | if (labels[index].q == q) | |
1352 | continue; | |
1353 | ||
1354 | lab = labels[index].label; | |
1355 | ||
1356 | if (index == return_index) | |
9a14ac4f | 1357 | do_return_redirection (q, lab, NULL); |
22347b24 | 1358 | else |
75a70cf9 | 1359 | do_goto_redirection (q, lab, NULL, tf); |
22347b24 | 1360 | } |
e38def9c | 1361 | |
4ee9c684 | 1362 | replace_goto_queue (tf); |
1363 | free (labels); | |
1364 | } | |
1365 | ||
1366 | /* Need to link new stmts after running replace_goto_queue due | |
1367 | to not wanting to process the same goto stmts twice. */ | |
75a70cf9 | 1368 | gimple_seq_add_seq (&tf->top_p_seq, new_stmt); |
4ee9c684 | 1369 | } |
1370 | ||
1371 | /* A subroutine of lower_try_finally. There are multiple edges incoming | |
1372 | and outgoing from the finally block. Implement this by instrumenting | |
1373 | each incoming edge and creating a switch statement at the end of the | |
1374 | finally block that branches to the appropriate destination. */ | |
1375 | ||
1376 | static void | |
1377 | lower_try_finally_switch (struct leh_state *state, struct leh_tf_state *tf) | |
1378 | { | |
1379 | struct goto_queue_node *q, *qe; | |
75a70cf9 | 1380 | tree finally_tmp, finally_label; |
4ee9c684 | 1381 | int return_index, eh_index, fallthru_index; |
1382 | int nlabels, ndests, j, last_case_index; | |
75a70cf9 | 1383 | tree last_case; |
f1f41a6c | 1384 | vec<tree> case_label_vec; |
e3a19533 | 1385 | gimple_seq switch_body = NULL; |
1a91d914 | 1386 | gimple x; |
1387 | geh_else *eh_else; | |
75a70cf9 | 1388 | tree tmp; |
1389 | gimple switch_stmt; | |
1390 | gimple_seq finally; | |
06ecf488 | 1391 | hash_map<tree, gimple> *cont_map = NULL; |
e60a6f7b | 1392 | /* The location of the TRY_FINALLY stmt. */ |
0b35068b | 1393 | location_t tf_loc = gimple_location (tf->try_finally_expr); |
e60a6f7b | 1394 | /* The location of the finally block. */ |
1395 | location_t finally_loc; | |
75a70cf9 | 1396 | |
4c0315d0 | 1397 | finally = gimple_try_cleanup (tf->top_p); |
1398 | eh_else = get_eh_else (finally); | |
4ee9c684 | 1399 | |
1400 | /* Mash the TRY block to the head of the chain. */ | |
75a70cf9 | 1401 | tf->top_p_seq = gimple_try_eval (tf->top_p); |
4ee9c684 | 1402 | |
e60a6f7b | 1403 | /* The location of the finally is either the last stmt in the finally |
1404 | block or the location of the TRY_FINALLY itself. */ | |
a6217c59 | 1405 | x = gimple_seq_last_stmt (finally); |
1406 | finally_loc = x ? gimple_location (x) : tf_loc; | |
e60a6f7b | 1407 | |
4ee9c684 | 1408 | /* Prepare for switch statement generation. */ |
f1f41a6c | 1409 | nlabels = tf->dest_array.length (); |
4ee9c684 | 1410 | return_index = nlabels; |
1411 | eh_index = return_index + tf->may_return; | |
4c0315d0 | 1412 | fallthru_index = eh_index + (tf->may_throw && !eh_else); |
4ee9c684 | 1413 | ndests = fallthru_index + tf->may_fallthru; |
1414 | ||
1415 | finally_tmp = create_tmp_var (integer_type_node, "finally_tmp"); | |
e60a6f7b | 1416 | finally_label = create_artificial_label (finally_loc); |
4ee9c684 | 1417 | |
f1f41a6c | 1418 | /* We use vec::quick_push on case_label_vec throughout this function, |
75a70cf9 | 1419 | since we know the size in advance and allocate precisely as muce |
1420 | space as needed. */ | |
f1f41a6c | 1421 | case_label_vec.create (ndests); |
4ee9c684 | 1422 | last_case = NULL; |
1423 | last_case_index = 0; | |
1424 | ||
1425 | /* Begin inserting code for getting to the finally block. Things | |
1426 | are done in this order to correspond to the sequence the code is | |
9d75589a | 1427 | laid out. */ |
4ee9c684 | 1428 | |
1429 | if (tf->may_fallthru) | |
1430 | { | |
e38def9c | 1431 | x = gimple_build_assign (finally_tmp, |
bad12c62 | 1432 | build_int_cst (integer_type_node, |
1433 | fallthru_index)); | |
75a70cf9 | 1434 | gimple_seq_add_stmt (&tf->top_p_seq, x); |
4ee9c684 | 1435 | |
b6e3dd65 | 1436 | tmp = build_int_cst (integer_type_node, fallthru_index); |
1437 | last_case = build_case_label (tmp, NULL, | |
1438 | create_artificial_label (tf_loc)); | |
f1f41a6c | 1439 | case_label_vec.quick_push (last_case); |
4ee9c684 | 1440 | last_case_index++; |
1441 | ||
75a70cf9 | 1442 | x = gimple_build_label (CASE_LABEL (last_case)); |
1443 | gimple_seq_add_stmt (&switch_body, x); | |
4ee9c684 | 1444 | |
75a70cf9 | 1445 | tmp = lower_try_finally_fallthru_label (tf); |
1446 | x = gimple_build_goto (tmp); | |
ed4d69dc | 1447 | gimple_set_location (x, tf_loc); |
75a70cf9 | 1448 | gimple_seq_add_stmt (&switch_body, x); |
4ee9c684 | 1449 | } |
1450 | ||
4c0315d0 | 1451 | /* For EH_ELSE, emit the exception path (plus resx) now, then |
1452 | subsequently we only need consider the normal path. */ | |
1453 | if (eh_else) | |
1454 | { | |
1455 | if (tf->may_throw) | |
1456 | { | |
1457 | finally = gimple_eh_else_e_body (eh_else); | |
e3a19533 | 1458 | lower_eh_constructs_1 (state, &finally); |
4c0315d0 | 1459 | |
1460 | emit_post_landing_pad (&eh_seq, tf->region); | |
1461 | gimple_seq_add_seq (&eh_seq, finally); | |
1462 | emit_resx (&eh_seq, tf->region); | |
1463 | } | |
1464 | ||
1465 | finally = gimple_eh_else_n_body (eh_else); | |
1466 | } | |
1467 | else if (tf->may_throw) | |
4ee9c684 | 1468 | { |
e38def9c | 1469 | emit_post_landing_pad (&eh_seq, tf->region); |
4ee9c684 | 1470 | |
e38def9c | 1471 | x = gimple_build_assign (finally_tmp, |
bad12c62 | 1472 | build_int_cst (integer_type_node, eh_index)); |
e38def9c | 1473 | gimple_seq_add_stmt (&eh_seq, x); |
1474 | ||
1475 | x = gimple_build_goto (finally_label); | |
ed4d69dc | 1476 | gimple_set_location (x, tf_loc); |
e38def9c | 1477 | gimple_seq_add_stmt (&eh_seq, x); |
4ee9c684 | 1478 | |
b6e3dd65 | 1479 | tmp = build_int_cst (integer_type_node, eh_index); |
1480 | last_case = build_case_label (tmp, NULL, | |
1481 | create_artificial_label (tf_loc)); | |
f1f41a6c | 1482 | case_label_vec.quick_push (last_case); |
4ee9c684 | 1483 | last_case_index++; |
1484 | ||
75a70cf9 | 1485 | x = gimple_build_label (CASE_LABEL (last_case)); |
e38def9c | 1486 | gimple_seq_add_stmt (&eh_seq, x); |
1487 | emit_resx (&eh_seq, tf->region); | |
4ee9c684 | 1488 | } |
1489 | ||
75a70cf9 | 1490 | x = gimple_build_label (finally_label); |
1491 | gimple_seq_add_stmt (&tf->top_p_seq, x); | |
4ee9c684 | 1492 | |
9ae6e329 | 1493 | lower_eh_constructs_1 (state, &finally); |
75a70cf9 | 1494 | gimple_seq_add_seq (&tf->top_p_seq, finally); |
4ee9c684 | 1495 | |
1496 | /* Redirect each incoming goto edge. */ | |
1497 | q = tf->goto_queue; | |
1498 | qe = q + tf->goto_queue_active; | |
1499 | j = last_case_index + tf->may_return; | |
75a70cf9 | 1500 | /* Prepare the assignments to finally_tmp that are executed upon the |
1501 | entrance through a particular edge. */ | |
4ee9c684 | 1502 | for (; q < qe; ++q) |
1503 | { | |
e3a19533 | 1504 | gimple_seq mod = NULL; |
75a70cf9 | 1505 | int switch_id; |
1506 | unsigned int case_index; | |
1507 | ||
4ee9c684 | 1508 | if (q->index < 0) |
1509 | { | |
75a70cf9 | 1510 | x = gimple_build_assign (finally_tmp, |
bad12c62 | 1511 | build_int_cst (integer_type_node, |
1512 | return_index)); | |
75a70cf9 | 1513 | gimple_seq_add_stmt (&mod, x); |
9a14ac4f | 1514 | do_return_redirection (q, finally_label, mod); |
4ee9c684 | 1515 | switch_id = return_index; |
1516 | } | |
1517 | else | |
1518 | { | |
75a70cf9 | 1519 | x = gimple_build_assign (finally_tmp, |
bad12c62 | 1520 | build_int_cst (integer_type_node, q->index)); |
75a70cf9 | 1521 | gimple_seq_add_stmt (&mod, x); |
1522 | do_goto_redirection (q, finally_label, mod, tf); | |
4ee9c684 | 1523 | switch_id = q->index; |
1524 | } | |
1525 | ||
1526 | case_index = j + q->index; | |
f1f41a6c | 1527 | if (case_label_vec.length () <= case_index || !case_label_vec[case_index]) |
75a70cf9 | 1528 | { |
1529 | tree case_lab; | |
b6e3dd65 | 1530 | tmp = build_int_cst (integer_type_node, switch_id); |
1531 | case_lab = build_case_label (tmp, NULL, | |
1532 | create_artificial_label (tf_loc)); | |
75a70cf9 | 1533 | /* We store the cont_stmt in the pointer map, so that we can recover |
75a2cdc8 | 1534 | it in the loop below. */ |
75a70cf9 | 1535 | if (!cont_map) |
06ecf488 | 1536 | cont_map = new hash_map<tree, gimple>; |
1537 | cont_map->put (case_lab, q->cont_stmt); | |
f1f41a6c | 1538 | case_label_vec.quick_push (case_lab); |
75a70cf9 | 1539 | } |
22347b24 | 1540 | } |
1541 | for (j = last_case_index; j < last_case_index + nlabels; j++) | |
1542 | { | |
75a70cf9 | 1543 | gimple cont_stmt; |
22347b24 | 1544 | |
f1f41a6c | 1545 | last_case = case_label_vec[j]; |
22347b24 | 1546 | |
1547 | gcc_assert (last_case); | |
75a70cf9 | 1548 | gcc_assert (cont_map); |
22347b24 | 1549 | |
06ecf488 | 1550 | cont_stmt = *cont_map->get (last_case); |
22347b24 | 1551 | |
75a2cdc8 | 1552 | x = gimple_build_label (CASE_LABEL (last_case)); |
75a70cf9 | 1553 | gimple_seq_add_stmt (&switch_body, x); |
1554 | gimple_seq_add_stmt (&switch_body, cont_stmt); | |
22347b24 | 1555 | maybe_record_in_goto_queue (state, cont_stmt); |
4ee9c684 | 1556 | } |
75a70cf9 | 1557 | if (cont_map) |
06ecf488 | 1558 | delete cont_map; |
75a70cf9 | 1559 | |
4ee9c684 | 1560 | replace_goto_queue (tf); |
4ee9c684 | 1561 | |
da41aa8e | 1562 | /* Make sure that the last case is the default label, as one is required. |
1563 | Then sort the labels, which is also required in GIMPLE. */ | |
4ee9c684 | 1564 | CASE_LOW (last_case) = NULL; |
71b65939 | 1565 | tree tem = case_label_vec.pop (); |
1566 | gcc_assert (tem == last_case); | |
da41aa8e | 1567 | sort_case_labels (case_label_vec); |
4ee9c684 | 1568 | |
75a70cf9 | 1569 | /* Build the switch statement, setting last_case to be the default |
1570 | label. */ | |
49a70175 | 1571 | switch_stmt = gimple_build_switch (finally_tmp, last_case, |
1572 | case_label_vec); | |
e60a6f7b | 1573 | gimple_set_location (switch_stmt, finally_loc); |
75a70cf9 | 1574 | |
1575 | /* Need to link SWITCH_STMT after running replace_goto_queue | |
1576 | due to not wanting to process the same goto stmts twice. */ | |
1577 | gimple_seq_add_stmt (&tf->top_p_seq, switch_stmt); | |
1578 | gimple_seq_add_seq (&tf->top_p_seq, switch_body); | |
4ee9c684 | 1579 | } |
1580 | ||
1581 | /* Decide whether or not we are going to duplicate the finally block. | |
1582 | There are several considerations. | |
1583 | ||
1584 | First, if this is Java, then the finally block contains code | |
1585 | written by the user. It has line numbers associated with it, | |
1586 | so duplicating the block means it's difficult to set a breakpoint. | |
1587 | Since controlling code generation via -g is verboten, we simply | |
1588 | never duplicate code without optimization. | |
1589 | ||
1590 | Second, we'd like to prevent egregious code growth. One way to | |
1591 | do this is to estimate the size of the finally block, multiply | |
1592 | that by the number of copies we'd need to make, and compare against | |
1593 | the estimate of the size of the switch machinery we'd have to add. */ | |
1594 | ||
1595 | static bool | |
4c0315d0 | 1596 | decide_copy_try_finally (int ndests, bool may_throw, gimple_seq finally) |
4ee9c684 | 1597 | { |
1598 | int f_estimate, sw_estimate; | |
1a91d914 | 1599 | geh_else *eh_else; |
4c0315d0 | 1600 | |
1601 | /* If there's an EH_ELSE involved, the exception path is separate | |
1602 | and really doesn't come into play for this computation. */ | |
1603 | eh_else = get_eh_else (finally); | |
1604 | if (eh_else) | |
1605 | { | |
1606 | ndests -= may_throw; | |
1607 | finally = gimple_eh_else_n_body (eh_else); | |
1608 | } | |
4ee9c684 | 1609 | |
1610 | if (!optimize) | |
83480f35 | 1611 | { |
1612 | gimple_stmt_iterator gsi; | |
1613 | ||
1614 | if (ndests == 1) | |
1615 | return true; | |
1616 | ||
1617 | for (gsi = gsi_start (finally); !gsi_end_p (gsi); gsi_next (&gsi)) | |
1618 | { | |
1619 | gimple stmt = gsi_stmt (gsi); | |
1620 | if (!is_gimple_debug (stmt) && !gimple_clobber_p (stmt)) | |
1621 | return false; | |
1622 | } | |
1623 | return true; | |
1624 | } | |
4ee9c684 | 1625 | |
1626 | /* Finally estimate N times, plus N gotos. */ | |
75a70cf9 | 1627 | f_estimate = count_insns_seq (finally, &eni_size_weights); |
4ee9c684 | 1628 | f_estimate = (f_estimate + 1) * ndests; |
1629 | ||
1630 | /* Switch statement (cost 10), N variable assignments, N gotos. */ | |
1631 | sw_estimate = 10 + 2 * ndests; | |
1632 | ||
1633 | /* Optimize for size clearly wants our best guess. */ | |
0bfd8d5c | 1634 | if (optimize_function_for_size_p (cfun)) |
4ee9c684 | 1635 | return f_estimate < sw_estimate; |
1636 | ||
1637 | /* ??? These numbers are completely made up so far. */ | |
1638 | if (optimize > 1) | |
72c90b15 | 1639 | return f_estimate < 100 || f_estimate < sw_estimate * 2; |
4ee9c684 | 1640 | else |
72c90b15 | 1641 | return f_estimate < 40 || f_estimate * 2 < sw_estimate * 3; |
4ee9c684 | 1642 | } |
1643 | ||
f340b9ff | 1644 | /* REG is the enclosing region for a possible cleanup region, or the region |
1645 | itself. Returns TRUE if such a region would be unreachable. | |
1646 | ||
1647 | Cleanup regions within a must-not-throw region aren't actually reachable | |
1648 | even if there are throwing stmts within them, because the personality | |
1649 | routine will call terminate before unwinding. */ | |
1650 | ||
1651 | static bool | |
1652 | cleanup_is_dead_in (eh_region reg) | |
1653 | { | |
1654 | while (reg && reg->type == ERT_CLEANUP) | |
1655 | reg = reg->outer; | |
1656 | return (reg && reg->type == ERT_MUST_NOT_THROW); | |
1657 | } | |
75a70cf9 | 1658 | |
1659 | /* A subroutine of lower_eh_constructs_1. Lower a GIMPLE_TRY_FINALLY nodes | |
4ee9c684 | 1660 | to a sequence of labels and blocks, plus the exception region trees |
ac13e8d9 | 1661 | that record all the magic. This is complicated by the need to |
4ee9c684 | 1662 | arrange for the FINALLY block to be executed on all exits. */ |
1663 | ||
75a70cf9 | 1664 | static gimple_seq |
1a91d914 | 1665 | lower_try_finally (struct leh_state *state, gtry *tp) |
4ee9c684 | 1666 | { |
1667 | struct leh_tf_state this_tf; | |
1668 | struct leh_state this_state; | |
1669 | int ndests; | |
fa5d8988 | 1670 | gimple_seq old_eh_seq; |
4ee9c684 | 1671 | |
1672 | /* Process the try block. */ | |
1673 | ||
1674 | memset (&this_tf, 0, sizeof (this_tf)); | |
75a70cf9 | 1675 | this_tf.try_finally_expr = tp; |
4ee9c684 | 1676 | this_tf.top_p = tp; |
1677 | this_tf.outer = state; | |
4e57e76d | 1678 | if (using_eh_for_cleanups_p () && !cleanup_is_dead_in (state->cur_region)) |
f340b9ff | 1679 | { |
1680 | this_tf.region = gen_eh_region_cleanup (state->cur_region); | |
1681 | this_state.cur_region = this_tf.region; | |
1682 | } | |
4ee9c684 | 1683 | else |
f340b9ff | 1684 | { |
1685 | this_tf.region = NULL; | |
1686 | this_state.cur_region = state->cur_region; | |
1687 | } | |
4ee9c684 | 1688 | |
e38def9c | 1689 | this_state.ehp_region = state->ehp_region; |
4ee9c684 | 1690 | this_state.tf = &this_tf; |
1691 | ||
fa5d8988 | 1692 | old_eh_seq = eh_seq; |
1693 | eh_seq = NULL; | |
1694 | ||
e3a19533 | 1695 | lower_eh_constructs_1 (&this_state, gimple_try_eval_ptr (tp)); |
4ee9c684 | 1696 | |
1697 | /* Determine if the try block is escaped through the bottom. */ | |
75a70cf9 | 1698 | this_tf.may_fallthru = gimple_seq_may_fallthru (gimple_try_eval (tp)); |
4ee9c684 | 1699 | |
1700 | /* Determine if any exceptions are possible within the try block. */ | |
f340b9ff | 1701 | if (this_tf.region) |
55d6d4e4 | 1702 | this_tf.may_throw = eh_region_may_contain_throw (this_tf.region); |
4ee9c684 | 1703 | if (this_tf.may_throw) |
e38def9c | 1704 | honor_protect_cleanup_actions (state, &this_state, &this_tf); |
4ee9c684 | 1705 | |
4ee9c684 | 1706 | /* Determine how many edges (still) reach the finally block. Or rather, |
1707 | how many destinations are reached by the finally block. Use this to | |
1708 | determine how we process the finally block itself. */ | |
1709 | ||
f1f41a6c | 1710 | ndests = this_tf.dest_array.length (); |
4ee9c684 | 1711 | ndests += this_tf.may_fallthru; |
1712 | ndests += this_tf.may_return; | |
1713 | ndests += this_tf.may_throw; | |
1714 | ||
1715 | /* If the FINALLY block is not reachable, dike it out. */ | |
1716 | if (ndests == 0) | |
75a70cf9 | 1717 | { |
1718 | gimple_seq_add_seq (&this_tf.top_p_seq, gimple_try_eval (tp)); | |
1719 | gimple_try_set_cleanup (tp, NULL); | |
1720 | } | |
4ee9c684 | 1721 | /* If the finally block doesn't fall through, then any destination |
1722 | we might try to impose there isn't reached either. There may be | |
1723 | some minor amount of cleanup and redirection still needed. */ | |
75a70cf9 | 1724 | else if (!gimple_seq_may_fallthru (gimple_try_cleanup (tp))) |
4ee9c684 | 1725 | lower_try_finally_nofallthru (state, &this_tf); |
1726 | ||
1727 | /* We can easily special-case redirection to a single destination. */ | |
1728 | else if (ndests == 1) | |
1729 | lower_try_finally_onedest (state, &this_tf); | |
4c0315d0 | 1730 | else if (decide_copy_try_finally (ndests, this_tf.may_throw, |
1731 | gimple_try_cleanup (tp))) | |
4ee9c684 | 1732 | lower_try_finally_copy (state, &this_tf); |
1733 | else | |
1734 | lower_try_finally_switch (state, &this_tf); | |
1735 | ||
1736 | /* If someone requested we add a label at the end of the transformed | |
1737 | block, do so. */ | |
1738 | if (this_tf.fallthru_label) | |
1739 | { | |
75a70cf9 | 1740 | /* This must be reached only if ndests == 0. */ |
1741 | gimple x = gimple_build_label (this_tf.fallthru_label); | |
1742 | gimple_seq_add_stmt (&this_tf.top_p_seq, x); | |
4ee9c684 | 1743 | } |
1744 | ||
f1f41a6c | 1745 | this_tf.dest_array.release (); |
dd045aee | 1746 | free (this_tf.goto_queue); |
46699809 | 1747 | if (this_tf.goto_queue_map) |
06ecf488 | 1748 | delete this_tf.goto_queue_map; |
75a70cf9 | 1749 | |
fa5d8988 | 1750 | /* If there was an old (aka outer) eh_seq, append the current eh_seq. |
1751 | If there was no old eh_seq, then the append is trivially already done. */ | |
1752 | if (old_eh_seq) | |
1753 | { | |
1754 | if (eh_seq == NULL) | |
1755 | eh_seq = old_eh_seq; | |
1756 | else | |
1757 | { | |
1758 | gimple_seq new_eh_seq = eh_seq; | |
1759 | eh_seq = old_eh_seq; | |
9af5ce0c | 1760 | gimple_seq_add_seq (&eh_seq, new_eh_seq); |
fa5d8988 | 1761 | } |
1762 | } | |
1763 | ||
75a70cf9 | 1764 | return this_tf.top_p_seq; |
4ee9c684 | 1765 | } |
1766 | ||
75a70cf9 | 1767 | /* A subroutine of lower_eh_constructs_1. Lower a GIMPLE_TRY_CATCH with a |
1768 | list of GIMPLE_CATCH to a sequence of labels and blocks, plus the | |
1769 | exception region trees that records all the magic. */ | |
4ee9c684 | 1770 | |
75a70cf9 | 1771 | static gimple_seq |
1a91d914 | 1772 | lower_catch (struct leh_state *state, gtry *tp) |
4ee9c684 | 1773 | { |
55d6d4e4 | 1774 | eh_region try_region = NULL; |
1775 | struct leh_state this_state = *state; | |
75a70cf9 | 1776 | gimple_stmt_iterator gsi; |
4ee9c684 | 1777 | tree out_label; |
e3a19533 | 1778 | gimple_seq new_seq, cleanup; |
e38def9c | 1779 | gimple x; |
e60a6f7b | 1780 | location_t try_catch_loc = gimple_location (tp); |
4ee9c684 | 1781 | |
55d6d4e4 | 1782 | if (flag_exceptions) |
1783 | { | |
1784 | try_region = gen_eh_region_try (state->cur_region); | |
1785 | this_state.cur_region = try_region; | |
1786 | } | |
4ee9c684 | 1787 | |
e3a19533 | 1788 | lower_eh_constructs_1 (&this_state, gimple_try_eval_ptr (tp)); |
4ee9c684 | 1789 | |
55d6d4e4 | 1790 | if (!eh_region_may_contain_throw (try_region)) |
e38def9c | 1791 | return gimple_try_eval (tp); |
1792 | ||
1793 | new_seq = NULL; | |
1794 | emit_eh_dispatch (&new_seq, try_region); | |
1795 | emit_resx (&new_seq, try_region); | |
1796 | ||
1797 | this_state.cur_region = state->cur_region; | |
1798 | this_state.ehp_region = try_region; | |
4ee9c684 | 1799 | |
4422041b | 1800 | /* Add eh_seq from lowering EH in the cleanup sequence after the cleanup |
1801 | itself, so that e.g. for coverage purposes the nested cleanups don't | |
1802 | appear before the cleanup body. See PR64634 for details. */ | |
1803 | gimple_seq old_eh_seq = eh_seq; | |
1804 | eh_seq = NULL; | |
1805 | ||
4ee9c684 | 1806 | out_label = NULL; |
e3a19533 | 1807 | cleanup = gimple_try_cleanup (tp); |
1808 | for (gsi = gsi_start (cleanup); | |
e38def9c | 1809 | !gsi_end_p (gsi); |
1810 | gsi_next (&gsi)) | |
4ee9c684 | 1811 | { |
e38def9c | 1812 | eh_catch c; |
1a91d914 | 1813 | gcatch *catch_stmt; |
e38def9c | 1814 | gimple_seq handler; |
4ee9c684 | 1815 | |
1a91d914 | 1816 | catch_stmt = as_a <gcatch *> (gsi_stmt (gsi)); |
1817 | c = gen_eh_region_catch (try_region, gimple_catch_types (catch_stmt)); | |
4ee9c684 | 1818 | |
1a91d914 | 1819 | handler = gimple_catch_handler (catch_stmt); |
e3a19533 | 1820 | lower_eh_constructs_1 (&this_state, &handler); |
4ee9c684 | 1821 | |
e38def9c | 1822 | c->label = create_artificial_label (UNKNOWN_LOCATION); |
1823 | x = gimple_build_label (c->label); | |
1824 | gimple_seq_add_stmt (&new_seq, x); | |
4ee9c684 | 1825 | |
e38def9c | 1826 | gimple_seq_add_seq (&new_seq, handler); |
4ee9c684 | 1827 | |
e38def9c | 1828 | if (gimple_seq_may_fallthru (new_seq)) |
4ee9c684 | 1829 | { |
1830 | if (!out_label) | |
e60a6f7b | 1831 | out_label = create_artificial_label (try_catch_loc); |
4ee9c684 | 1832 | |
75a70cf9 | 1833 | x = gimple_build_goto (out_label); |
e38def9c | 1834 | gimple_seq_add_stmt (&new_seq, x); |
4ee9c684 | 1835 | } |
3ded67b5 | 1836 | if (!c->type_list) |
1837 | break; | |
4ee9c684 | 1838 | } |
1839 | ||
e38def9c | 1840 | gimple_try_set_cleanup (tp, new_seq); |
1841 | ||
4422041b | 1842 | gimple_seq new_eh_seq = eh_seq; |
1843 | eh_seq = old_eh_seq; | |
1844 | gimple_seq ret_seq = frob_into_branch_around (tp, try_region, out_label); | |
1845 | gimple_seq_add_seq (&eh_seq, new_eh_seq); | |
1846 | return ret_seq; | |
4ee9c684 | 1847 | } |
1848 | ||
75a70cf9 | 1849 | /* A subroutine of lower_eh_constructs_1. Lower a GIMPLE_TRY with a |
1850 | GIMPLE_EH_FILTER to a sequence of labels and blocks, plus the exception | |
4ee9c684 | 1851 | region trees that record all the magic. */ |
1852 | ||
75a70cf9 | 1853 | static gimple_seq |
1a91d914 | 1854 | lower_eh_filter (struct leh_state *state, gtry *tp) |
4ee9c684 | 1855 | { |
55d6d4e4 | 1856 | struct leh_state this_state = *state; |
1857 | eh_region this_region = NULL; | |
e38def9c | 1858 | gimple inner, x; |
1859 | gimple_seq new_seq; | |
ac13e8d9 | 1860 | |
75a70cf9 | 1861 | inner = gimple_seq_first_stmt (gimple_try_cleanup (tp)); |
1862 | ||
55d6d4e4 | 1863 | if (flag_exceptions) |
1864 | { | |
1865 | this_region = gen_eh_region_allowed (state->cur_region, | |
1866 | gimple_eh_filter_types (inner)); | |
1867 | this_state.cur_region = this_region; | |
1868 | } | |
ac13e8d9 | 1869 | |
e3a19533 | 1870 | lower_eh_constructs_1 (&this_state, gimple_try_eval_ptr (tp)); |
4ee9c684 | 1871 | |
55d6d4e4 | 1872 | if (!eh_region_may_contain_throw (this_region)) |
e38def9c | 1873 | return gimple_try_eval (tp); |
1874 | ||
1875 | new_seq = NULL; | |
1876 | this_state.cur_region = state->cur_region; | |
1877 | this_state.ehp_region = this_region; | |
1878 | ||
1879 | emit_eh_dispatch (&new_seq, this_region); | |
1880 | emit_resx (&new_seq, this_region); | |
1881 | ||
1882 | this_region->u.allowed.label = create_artificial_label (UNKNOWN_LOCATION); | |
1883 | x = gimple_build_label (this_region->u.allowed.label); | |
1884 | gimple_seq_add_stmt (&new_seq, x); | |
1885 | ||
e3a19533 | 1886 | lower_eh_constructs_1 (&this_state, gimple_eh_filter_failure_ptr (inner)); |
e38def9c | 1887 | gimple_seq_add_seq (&new_seq, gimple_eh_filter_failure (inner)); |
1888 | ||
1889 | gimple_try_set_cleanup (tp, new_seq); | |
4ee9c684 | 1890 | |
e38def9c | 1891 | return frob_into_branch_around (tp, this_region, NULL); |
1892 | } | |
1893 | ||
1894 | /* A subroutine of lower_eh_constructs_1. Lower a GIMPLE_TRY with | |
1895 | an GIMPLE_EH_MUST_NOT_THROW to a sequence of labels and blocks, | |
1896 | plus the exception region trees that record all the magic. */ | |
1897 | ||
1898 | static gimple_seq | |
1a91d914 | 1899 | lower_eh_must_not_throw (struct leh_state *state, gtry *tp) |
e38def9c | 1900 | { |
55d6d4e4 | 1901 | struct leh_state this_state = *state; |
e38def9c | 1902 | |
55d6d4e4 | 1903 | if (flag_exceptions) |
1904 | { | |
1905 | gimple inner = gimple_seq_first_stmt (gimple_try_cleanup (tp)); | |
1906 | eh_region this_region; | |
e38def9c | 1907 | |
55d6d4e4 | 1908 | this_region = gen_eh_region_must_not_throw (state->cur_region); |
1909 | this_region->u.must_not_throw.failure_decl | |
1a91d914 | 1910 | = gimple_eh_must_not_throw_fndecl ( |
1911 | as_a <geh_mnt *> (inner)); | |
0565e0b5 | 1912 | this_region->u.must_not_throw.failure_loc |
1913 | = LOCATION_LOCUS (gimple_location (tp)); | |
e38def9c | 1914 | |
55d6d4e4 | 1915 | /* In order to get mangling applied to this decl, we must mark it |
1916 | used now. Otherwise, pass_ipa_free_lang_data won't think it | |
1917 | needs to happen. */ | |
1918 | TREE_USED (this_region->u.must_not_throw.failure_decl) = 1; | |
e38def9c | 1919 | |
55d6d4e4 | 1920 | this_state.cur_region = this_region; |
1921 | } | |
4ee9c684 | 1922 | |
e3a19533 | 1923 | lower_eh_constructs_1 (&this_state, gimple_try_eval_ptr (tp)); |
4ee9c684 | 1924 | |
e38def9c | 1925 | return gimple_try_eval (tp); |
4ee9c684 | 1926 | } |
1927 | ||
1928 | /* Implement a cleanup expression. This is similar to try-finally, | |
1929 | except that we only execute the cleanup block for exception edges. */ | |
1930 | ||
75a70cf9 | 1931 | static gimple_seq |
1a91d914 | 1932 | lower_cleanup (struct leh_state *state, gtry *tp) |
4ee9c684 | 1933 | { |
55d6d4e4 | 1934 | struct leh_state this_state = *state; |
1935 | eh_region this_region = NULL; | |
4ee9c684 | 1936 | struct leh_tf_state fake_tf; |
75a70cf9 | 1937 | gimple_seq result; |
f340b9ff | 1938 | bool cleanup_dead = cleanup_is_dead_in (state->cur_region); |
4ee9c684 | 1939 | |
f340b9ff | 1940 | if (flag_exceptions && !cleanup_dead) |
4ee9c684 | 1941 | { |
55d6d4e4 | 1942 | this_region = gen_eh_region_cleanup (state->cur_region); |
1943 | this_state.cur_region = this_region; | |
4ee9c684 | 1944 | } |
1945 | ||
e3a19533 | 1946 | lower_eh_constructs_1 (&this_state, gimple_try_eval_ptr (tp)); |
4ee9c684 | 1947 | |
f340b9ff | 1948 | if (cleanup_dead || !eh_region_may_contain_throw (this_region)) |
e38def9c | 1949 | return gimple_try_eval (tp); |
4ee9c684 | 1950 | |
1951 | /* Build enough of a try-finally state so that we can reuse | |
1952 | honor_protect_cleanup_actions. */ | |
1953 | memset (&fake_tf, 0, sizeof (fake_tf)); | |
e60a6f7b | 1954 | fake_tf.top_p = fake_tf.try_finally_expr = tp; |
4ee9c684 | 1955 | fake_tf.outer = state; |
1956 | fake_tf.region = this_region; | |
75a70cf9 | 1957 | fake_tf.may_fallthru = gimple_seq_may_fallthru (gimple_try_eval (tp)); |
4ee9c684 | 1958 | fake_tf.may_throw = true; |
1959 | ||
4ee9c684 | 1960 | honor_protect_cleanup_actions (state, NULL, &fake_tf); |
1961 | ||
1962 | if (fake_tf.may_throw) | |
1963 | { | |
1964 | /* In this case honor_protect_cleanup_actions had nothing to do, | |
1965 | and we should process this normally. */ | |
e3a19533 | 1966 | lower_eh_constructs_1 (state, gimple_try_cleanup_ptr (tp)); |
e38def9c | 1967 | result = frob_into_branch_around (tp, this_region, |
1968 | fake_tf.fallthru_label); | |
4ee9c684 | 1969 | } |
1970 | else | |
1971 | { | |
1972 | /* In this case honor_protect_cleanup_actions did nearly all of | |
1973 | the work. All we have left is to append the fallthru_label. */ | |
1974 | ||
75a70cf9 | 1975 | result = gimple_try_eval (tp); |
4ee9c684 | 1976 | if (fake_tf.fallthru_label) |
1977 | { | |
75a70cf9 | 1978 | gimple x = gimple_build_label (fake_tf.fallthru_label); |
1979 | gimple_seq_add_stmt (&result, x); | |
4ee9c684 | 1980 | } |
1981 | } | |
75a70cf9 | 1982 | return result; |
4ee9c684 | 1983 | } |
1984 | ||
e38def9c | 1985 | /* Main loop for lowering eh constructs. Also moves gsi to the next |
75a70cf9 | 1986 | statement. */ |
4ee9c684 | 1987 | |
1988 | static void | |
75a70cf9 | 1989 | lower_eh_constructs_2 (struct leh_state *state, gimple_stmt_iterator *gsi) |
4ee9c684 | 1990 | { |
75a70cf9 | 1991 | gimple_seq replace; |
1992 | gimple x; | |
1993 | gimple stmt = gsi_stmt (*gsi); | |
4ee9c684 | 1994 | |
75a70cf9 | 1995 | switch (gimple_code (stmt)) |
4ee9c684 | 1996 | { |
75a70cf9 | 1997 | case GIMPLE_CALL: |
e38def9c | 1998 | { |
1999 | tree fndecl = gimple_call_fndecl (stmt); | |
2000 | tree rhs, lhs; | |
2001 | ||
2002 | if (fndecl && DECL_BUILT_IN_CLASS (fndecl) == BUILT_IN_NORMAL) | |
2003 | switch (DECL_FUNCTION_CODE (fndecl)) | |
2004 | { | |
2005 | case BUILT_IN_EH_POINTER: | |
2006 | /* The front end may have generated a call to | |
2007 | __builtin_eh_pointer (0) within a catch region. Replace | |
2008 | this zero argument with the current catch region number. */ | |
2009 | if (state->ehp_region) | |
2010 | { | |
bad12c62 | 2011 | tree nr = build_int_cst (integer_type_node, |
2012 | state->ehp_region->index); | |
e38def9c | 2013 | gimple_call_set_arg (stmt, 0, nr); |
2014 | } | |
2015 | else | |
2016 | { | |
2017 | /* The user has dome something silly. Remove it. */ | |
2512209b | 2018 | rhs = null_pointer_node; |
e38def9c | 2019 | goto do_replace; |
2020 | } | |
2021 | break; | |
2022 | ||
2023 | case BUILT_IN_EH_FILTER: | |
2024 | /* ??? This should never appear, but since it's a builtin it | |
2025 | is accessible to abuse by users. Just remove it and | |
2026 | replace the use with the arbitrary value zero. */ | |
2027 | rhs = build_int_cst (TREE_TYPE (TREE_TYPE (fndecl)), 0); | |
2028 | do_replace: | |
2029 | lhs = gimple_call_lhs (stmt); | |
2030 | x = gimple_build_assign (lhs, rhs); | |
2031 | gsi_insert_before (gsi, x, GSI_SAME_STMT); | |
2032 | /* FALLTHRU */ | |
2033 | ||
2034 | case BUILT_IN_EH_COPY_VALUES: | |
2035 | /* Likewise this should not appear. Remove it. */ | |
2036 | gsi_remove (gsi, true); | |
2037 | return; | |
2038 | ||
2039 | default: | |
2040 | break; | |
2041 | } | |
2042 | } | |
2043 | /* FALLTHRU */ | |
2044 | ||
75a70cf9 | 2045 | case GIMPLE_ASSIGN: |
47f11e84 | 2046 | /* If the stmt can throw use a new temporary for the assignment |
2047 | to a LHS. This makes sure the old value of the LHS is | |
fa916956 | 2048 | available on the EH edge. Only do so for statements that |
9d75589a | 2049 | potentially fall through (no noreturn calls e.g.), otherwise |
fa916956 | 2050 | this new assignment might create fake fallthru regions. */ |
47f11e84 | 2051 | if (stmt_could_throw_p (stmt) |
2052 | && gimple_has_lhs (stmt) | |
fa916956 | 2053 | && gimple_stmt_may_fallthru (stmt) |
47f11e84 | 2054 | && !tree_could_throw_p (gimple_get_lhs (stmt)) |
2055 | && is_gimple_reg_type (TREE_TYPE (gimple_get_lhs (stmt)))) | |
2056 | { | |
2057 | tree lhs = gimple_get_lhs (stmt); | |
f9e245b2 | 2058 | tree tmp = create_tmp_var (TREE_TYPE (lhs)); |
47f11e84 | 2059 | gimple s = gimple_build_assign (lhs, tmp); |
2060 | gimple_set_location (s, gimple_location (stmt)); | |
2061 | gimple_set_block (s, gimple_block (stmt)); | |
2062 | gimple_set_lhs (stmt, tmp); | |
2063 | if (TREE_CODE (TREE_TYPE (tmp)) == COMPLEX_TYPE | |
2064 | || TREE_CODE (TREE_TYPE (tmp)) == VECTOR_TYPE) | |
2065 | DECL_GIMPLE_REG_P (tmp) = 1; | |
2066 | gsi_insert_after (gsi, s, GSI_SAME_STMT); | |
2067 | } | |
4ee9c684 | 2068 | /* Look for things that can throw exceptions, and record them. */ |
75a70cf9 | 2069 | if (state->cur_region && stmt_could_throw_p (stmt)) |
4ee9c684 | 2070 | { |
75a70cf9 | 2071 | record_stmt_eh_region (state->cur_region, stmt); |
4ee9c684 | 2072 | note_eh_region_may_contain_throw (state->cur_region); |
4ee9c684 | 2073 | } |
2074 | break; | |
2075 | ||
75a70cf9 | 2076 | case GIMPLE_COND: |
2077 | case GIMPLE_GOTO: | |
2078 | case GIMPLE_RETURN: | |
2079 | maybe_record_in_goto_queue (state, stmt); | |
4ee9c684 | 2080 | break; |
2081 | ||
75a70cf9 | 2082 | case GIMPLE_SWITCH: |
1a91d914 | 2083 | verify_norecord_switch_expr (state, as_a <gswitch *> (stmt)); |
4ee9c684 | 2084 | break; |
2085 | ||
75a70cf9 | 2086 | case GIMPLE_TRY: |
1a91d914 | 2087 | { |
2088 | gtry *try_stmt = as_a <gtry *> (stmt); | |
2089 | if (gimple_try_kind (try_stmt) == GIMPLE_TRY_FINALLY) | |
2090 | replace = lower_try_finally (state, try_stmt); | |
2091 | else | |
2092 | { | |
2093 | x = gimple_seq_first_stmt (gimple_try_cleanup (try_stmt)); | |
2094 | if (!x) | |
c90b5d40 | 2095 | { |
1a91d914 | 2096 | replace = gimple_try_eval (try_stmt); |
2097 | lower_eh_constructs_1 (state, &replace); | |
2098 | } | |
2099 | else | |
2100 | switch (gimple_code (x)) | |
2101 | { | |
c90b5d40 | 2102 | case GIMPLE_CATCH: |
1a91d914 | 2103 | replace = lower_catch (state, try_stmt); |
2104 | break; | |
c90b5d40 | 2105 | case GIMPLE_EH_FILTER: |
1a91d914 | 2106 | replace = lower_eh_filter (state, try_stmt); |
2107 | break; | |
c90b5d40 | 2108 | case GIMPLE_EH_MUST_NOT_THROW: |
1a91d914 | 2109 | replace = lower_eh_must_not_throw (state, try_stmt); |
2110 | break; | |
4c0315d0 | 2111 | case GIMPLE_EH_ELSE: |
1a91d914 | 2112 | /* This code is only valid with GIMPLE_TRY_FINALLY. */ |
2113 | gcc_unreachable (); | |
c90b5d40 | 2114 | default: |
1a91d914 | 2115 | replace = lower_cleanup (state, try_stmt); |
2116 | break; | |
2117 | } | |
2118 | } | |
2119 | } | |
75a70cf9 | 2120 | |
2121 | /* Remove the old stmt and insert the transformed sequence | |
2122 | instead. */ | |
2123 | gsi_insert_seq_before (gsi, replace, GSI_SAME_STMT); | |
2124 | gsi_remove (gsi, true); | |
2125 | ||
2126 | /* Return since we don't want gsi_next () */ | |
2127 | return; | |
4ee9c684 | 2128 | |
4c0315d0 | 2129 | case GIMPLE_EH_ELSE: |
2130 | /* We should be eliminating this in lower_try_finally et al. */ | |
2131 | gcc_unreachable (); | |
2132 | ||
4ee9c684 | 2133 | default: |
2134 | /* A type, a decl, or some kind of statement that we're not | |
2135 | interested in. Don't walk them. */ | |
2136 | break; | |
2137 | } | |
75a70cf9 | 2138 | |
2139 | gsi_next (gsi); | |
2140 | } | |
2141 | ||
2142 | /* A helper to unwrap a gimple_seq and feed stmts to lower_eh_constructs_2. */ | |
2143 | ||
2144 | static void | |
e3a19533 | 2145 | lower_eh_constructs_1 (struct leh_state *state, gimple_seq *pseq) |
75a70cf9 | 2146 | { |
2147 | gimple_stmt_iterator gsi; | |
e3a19533 | 2148 | for (gsi = gsi_start (*pseq); !gsi_end_p (gsi);) |
75a70cf9 | 2149 | lower_eh_constructs_2 (state, &gsi); |
4ee9c684 | 2150 | } |
2151 | ||
65b0537f | 2152 | namespace { |
2153 | ||
2154 | const pass_data pass_data_lower_eh = | |
2155 | { | |
2156 | GIMPLE_PASS, /* type */ | |
2157 | "eh", /* name */ | |
2158 | OPTGROUP_NONE, /* optinfo_flags */ | |
65b0537f | 2159 | TV_TREE_EH, /* tv_id */ |
2160 | PROP_gimple_lcf, /* properties_required */ | |
2161 | PROP_gimple_leh, /* properties_provided */ | |
2162 | 0, /* properties_destroyed */ | |
2163 | 0, /* todo_flags_start */ | |
2164 | 0, /* todo_flags_finish */ | |
2165 | }; | |
2166 | ||
2167 | class pass_lower_eh : public gimple_opt_pass | |
2168 | { | |
2169 | public: | |
2170 | pass_lower_eh (gcc::context *ctxt) | |
2171 | : gimple_opt_pass (pass_data_lower_eh, ctxt) | |
2172 | {} | |
2173 | ||
2174 | /* opt_pass methods: */ | |
2175 | virtual unsigned int execute (function *); | |
2176 | ||
2177 | }; // class pass_lower_eh | |
2178 | ||
2179 | unsigned int | |
2180 | pass_lower_eh::execute (function *fun) | |
4ee9c684 | 2181 | { |
2182 | struct leh_state null_state; | |
e38def9c | 2183 | gimple_seq bodyp; |
75a70cf9 | 2184 | |
e38def9c | 2185 | bodyp = gimple_body (current_function_decl); |
2186 | if (bodyp == NULL) | |
2187 | return 0; | |
4ee9c684 | 2188 | |
c1f445d2 | 2189 | finally_tree = new hash_table<finally_tree_hasher> (31); |
55d6d4e4 | 2190 | eh_region_may_contain_throw_map = BITMAP_ALLOC (NULL); |
e38def9c | 2191 | memset (&null_state, 0, sizeof (null_state)); |
4ee9c684 | 2192 | |
75a70cf9 | 2193 | collect_finally_tree_1 (bodyp, NULL); |
e3a19533 | 2194 | lower_eh_constructs_1 (&null_state, &bodyp); |
2195 | gimple_set_body (current_function_decl, bodyp); | |
4ee9c684 | 2196 | |
e38def9c | 2197 | /* We assume there's a return statement, or something, at the end of |
2198 | the function, and thus ploping the EH sequence afterward won't | |
2199 | change anything. */ | |
2200 | gcc_assert (!gimple_seq_may_fallthru (bodyp)); | |
2201 | gimple_seq_add_seq (&bodyp, eh_seq); | |
2202 | ||
2203 | /* We assume that since BODYP already existed, adding EH_SEQ to it | |
2204 | didn't change its value, and we don't have to re-set the function. */ | |
2205 | gcc_assert (bodyp == gimple_body (current_function_decl)); | |
4ee9c684 | 2206 | |
c1f445d2 | 2207 | delete finally_tree; |
2208 | finally_tree = NULL; | |
55d6d4e4 | 2209 | BITMAP_FREE (eh_region_may_contain_throw_map); |
e38def9c | 2210 | eh_seq = NULL; |
58d82cd0 | 2211 | |
2212 | /* If this function needs a language specific EH personality routine | |
2213 | and the frontend didn't already set one do so now. */ | |
65b0537f | 2214 | if (function_needs_eh_personality (fun) == eh_personality_lang |
58d82cd0 | 2215 | && !DECL_FUNCTION_PERSONALITY (current_function_decl)) |
2216 | DECL_FUNCTION_PERSONALITY (current_function_decl) | |
2217 | = lang_hooks.eh_personality (); | |
2218 | ||
2a1990e9 | 2219 | return 0; |
4ee9c684 | 2220 | } |
2221 | ||
cbe8bda8 | 2222 | } // anon namespace |
2223 | ||
2224 | gimple_opt_pass * | |
2225 | make_pass_lower_eh (gcc::context *ctxt) | |
2226 | { | |
2227 | return new pass_lower_eh (ctxt); | |
2228 | } | |
4ee9c684 | 2229 | \f |
e38def9c | 2230 | /* Create the multiple edges from an EH_DISPATCH statement to all of |
2231 | the possible handlers for its EH region. Return true if there's | |
2232 | no fallthru edge; false if there is. */ | |
4ee9c684 | 2233 | |
e38def9c | 2234 | bool |
1a91d914 | 2235 | make_eh_dispatch_edges (geh_dispatch *stmt) |
4ee9c684 | 2236 | { |
e38def9c | 2237 | eh_region r; |
2238 | eh_catch c; | |
4ee9c684 | 2239 | basic_block src, dst; |
2240 | ||
e38def9c | 2241 | r = get_eh_region_from_number (gimple_eh_dispatch_region (stmt)); |
75a70cf9 | 2242 | src = gimple_bb (stmt); |
4ee9c684 | 2243 | |
e38def9c | 2244 | switch (r->type) |
2245 | { | |
2246 | case ERT_TRY: | |
2247 | for (c = r->u.eh_try.first_catch; c ; c = c->next_catch) | |
2248 | { | |
2249 | dst = label_to_block (c->label); | |
2250 | make_edge (src, dst, 0); | |
ac13e8d9 | 2251 | |
e38def9c | 2252 | /* A catch-all handler doesn't have a fallthru. */ |
2253 | if (c->type_list == NULL) | |
2254 | return false; | |
2255 | } | |
2256 | break; | |
a5bfef5b | 2257 | |
e38def9c | 2258 | case ERT_ALLOWED_EXCEPTIONS: |
2259 | dst = label_to_block (r->u.allowed.label); | |
2260 | make_edge (src, dst, 0); | |
2261 | break; | |
2262 | ||
2263 | default: | |
2264 | gcc_unreachable (); | |
2265 | } | |
2266 | ||
2267 | return true; | |
a5bfef5b | 2268 | } |
2269 | ||
e38def9c | 2270 | /* Create the single EH edge from STMT to its nearest landing pad, |
2271 | if there is such a landing pad within the current function. */ | |
2272 | ||
4ee9c684 | 2273 | void |
75a70cf9 | 2274 | make_eh_edges (gimple stmt) |
4ee9c684 | 2275 | { |
e38def9c | 2276 | basic_block src, dst; |
2277 | eh_landing_pad lp; | |
2278 | int lp_nr; | |
4ee9c684 | 2279 | |
e38def9c | 2280 | lp_nr = lookup_stmt_eh_lp (stmt); |
2281 | if (lp_nr <= 0) | |
2282 | return; | |
4ee9c684 | 2283 | |
e38def9c | 2284 | lp = get_eh_landing_pad_from_number (lp_nr); |
2285 | gcc_assert (lp != NULL); | |
d6d5ab2d | 2286 | |
e38def9c | 2287 | src = gimple_bb (stmt); |
2288 | dst = label_to_block (lp->post_landing_pad); | |
2289 | make_edge (src, dst, EDGE_EH); | |
4ee9c684 | 2290 | } |
2291 | ||
e38def9c | 2292 | /* Do the work in redirecting EDGE_IN to NEW_BB within the EH region tree; |
2293 | do not actually perform the final edge redirection. | |
927a6b6b | 2294 | |
e38def9c | 2295 | CHANGE_REGION is true when we're being called from cleanup_empty_eh and |
2296 | we intend to change the destination EH region as well; this means | |
2297 | EH_LANDING_PAD_NR must already be set on the destination block label. | |
2298 | If false, we're being called from generic cfg manipulation code and we | |
2299 | should preserve our place within the region tree. */ | |
2300 | ||
2301 | static void | |
2302 | redirect_eh_edge_1 (edge edge_in, basic_block new_bb, bool change_region) | |
927a6b6b | 2303 | { |
e38def9c | 2304 | eh_landing_pad old_lp, new_lp; |
2305 | basic_block old_bb; | |
2306 | gimple throw_stmt; | |
2307 | int old_lp_nr, new_lp_nr; | |
2308 | tree old_label, new_label; | |
2309 | edge_iterator ei; | |
2310 | edge e; | |
2311 | ||
2312 | old_bb = edge_in->dest; | |
2313 | old_label = gimple_block_label (old_bb); | |
2314 | old_lp_nr = EH_LANDING_PAD_NR (old_label); | |
2315 | gcc_assert (old_lp_nr > 0); | |
2316 | old_lp = get_eh_landing_pad_from_number (old_lp_nr); | |
2317 | ||
2318 | throw_stmt = last_stmt (edge_in->src); | |
2319 | gcc_assert (lookup_stmt_eh_lp (throw_stmt) == old_lp_nr); | |
2320 | ||
2321 | new_label = gimple_block_label (new_bb); | |
927a6b6b | 2322 | |
e38def9c | 2323 | /* Look for an existing region that might be using NEW_BB already. */ |
2324 | new_lp_nr = EH_LANDING_PAD_NR (new_label); | |
2325 | if (new_lp_nr) | |
927a6b6b | 2326 | { |
e38def9c | 2327 | new_lp = get_eh_landing_pad_from_number (new_lp_nr); |
2328 | gcc_assert (new_lp); | |
48e1416a | 2329 | |
e38def9c | 2330 | /* Unless CHANGE_REGION is true, the new and old landing pad |
2331 | had better be associated with the same EH region. */ | |
2332 | gcc_assert (change_region || new_lp->region == old_lp->region); | |
927a6b6b | 2333 | } |
2334 | else | |
2335 | { | |
e38def9c | 2336 | new_lp = NULL; |
2337 | gcc_assert (!change_region); | |
927a6b6b | 2338 | } |
2339 | ||
e38def9c | 2340 | /* Notice when we redirect the last EH edge away from OLD_BB. */ |
2341 | FOR_EACH_EDGE (e, ei, old_bb->preds) | |
2342 | if (e != edge_in && (e->flags & EDGE_EH)) | |
2343 | break; | |
b4ba5e9d | 2344 | |
e38def9c | 2345 | if (new_lp) |
b4ba5e9d | 2346 | { |
e38def9c | 2347 | /* NEW_LP already exists. If there are still edges into OLD_LP, |
2348 | there's nothing to do with the EH tree. If there are no more | |
2349 | edges into OLD_LP, then we want to remove OLD_LP as it is unused. | |
2350 | If CHANGE_REGION is true, then our caller is expecting to remove | |
2351 | the landing pad. */ | |
2352 | if (e == NULL && !change_region) | |
2353 | remove_eh_landing_pad (old_lp); | |
b4ba5e9d | 2354 | } |
e38def9c | 2355 | else |
b4ba5e9d | 2356 | { |
e38def9c | 2357 | /* No correct landing pad exists. If there are no more edges |
2358 | into OLD_LP, then we can simply re-use the existing landing pad. | |
2359 | Otherwise, we have to create a new landing pad. */ | |
2360 | if (e == NULL) | |
2361 | { | |
2362 | EH_LANDING_PAD_NR (old_lp->post_landing_pad) = 0; | |
2363 | new_lp = old_lp; | |
2364 | } | |
2365 | else | |
2366 | new_lp = gen_eh_landing_pad (old_lp->region); | |
2367 | new_lp->post_landing_pad = new_label; | |
2368 | EH_LANDING_PAD_NR (new_label) = new_lp->index; | |
b4ba5e9d | 2369 | } |
e38def9c | 2370 | |
2371 | /* Maybe move the throwing statement to the new region. */ | |
2372 | if (old_lp != new_lp) | |
b4ba5e9d | 2373 | { |
e38def9c | 2374 | remove_stmt_from_eh_lp (throw_stmt); |
2375 | add_stmt_to_eh_lp (throw_stmt, new_lp->index); | |
b4ba5e9d | 2376 | } |
b4ba5e9d | 2377 | } |
2378 | ||
e38def9c | 2379 | /* Redirect EH edge E to NEW_BB. */ |
75a70cf9 | 2380 | |
e38def9c | 2381 | edge |
2382 | redirect_eh_edge (edge edge_in, basic_block new_bb) | |
b4ba5e9d | 2383 | { |
e38def9c | 2384 | redirect_eh_edge_1 (edge_in, new_bb, false); |
2385 | return ssa_redirect_edge (edge_in, new_bb); | |
2386 | } | |
b4ba5e9d | 2387 | |
e38def9c | 2388 | /* This is a subroutine of gimple_redirect_edge_and_branch. Update the |
2389 | labels for redirecting a non-fallthru EH_DISPATCH edge E to NEW_BB. | |
2390 | The actual edge update will happen in the caller. */ | |
b4ba5e9d | 2391 | |
e38def9c | 2392 | void |
1a91d914 | 2393 | redirect_eh_dispatch_edge (geh_dispatch *stmt, edge e, basic_block new_bb) |
e38def9c | 2394 | { |
2395 | tree new_lab = gimple_block_label (new_bb); | |
2396 | bool any_changed = false; | |
2397 | basic_block old_bb; | |
2398 | eh_region r; | |
2399 | eh_catch c; | |
2400 | ||
2401 | r = get_eh_region_from_number (gimple_eh_dispatch_region (stmt)); | |
2402 | switch (r->type) | |
b4ba5e9d | 2403 | { |
e38def9c | 2404 | case ERT_TRY: |
2405 | for (c = r->u.eh_try.first_catch; c ; c = c->next_catch) | |
b4ba5e9d | 2406 | { |
e38def9c | 2407 | old_bb = label_to_block (c->label); |
2408 | if (old_bb == e->dest) | |
2409 | { | |
2410 | c->label = new_lab; | |
2411 | any_changed = true; | |
2412 | } | |
b4ba5e9d | 2413 | } |
e38def9c | 2414 | break; |
2415 | ||
2416 | case ERT_ALLOWED_EXCEPTIONS: | |
2417 | old_bb = label_to_block (r->u.allowed.label); | |
2418 | gcc_assert (old_bb == e->dest); | |
2419 | r->u.allowed.label = new_lab; | |
2420 | any_changed = true; | |
2421 | break; | |
2422 | ||
2423 | default: | |
2424 | gcc_unreachable (); | |
b4ba5e9d | 2425 | } |
75a70cf9 | 2426 | |
e38def9c | 2427 | gcc_assert (any_changed); |
b4ba5e9d | 2428 | } |
4ee9c684 | 2429 | \f |
75a70cf9 | 2430 | /* Helper function for operation_could_trap_p and stmt_could_throw_p. */ |
2431 | ||
2ac47fdf | 2432 | bool |
75a70cf9 | 2433 | operation_could_trap_helper_p (enum tree_code op, |
2434 | bool fp_operation, | |
2435 | bool honor_trapv, | |
2436 | bool honor_nans, | |
2437 | bool honor_snans, | |
2438 | tree divisor, | |
2439 | bool *handled) | |
2440 | { | |
2441 | *handled = true; | |
2442 | switch (op) | |
2443 | { | |
2444 | case TRUNC_DIV_EXPR: | |
2445 | case CEIL_DIV_EXPR: | |
2446 | case FLOOR_DIV_EXPR: | |
2447 | case ROUND_DIV_EXPR: | |
2448 | case EXACT_DIV_EXPR: | |
2449 | case CEIL_MOD_EXPR: | |
2450 | case FLOOR_MOD_EXPR: | |
2451 | case ROUND_MOD_EXPR: | |
2452 | case TRUNC_MOD_EXPR: | |
2453 | case RDIV_EXPR: | |
2454 | if (honor_snans || honor_trapv) | |
2455 | return true; | |
2456 | if (fp_operation) | |
2457 | return flag_trapping_math; | |
2458 | if (!TREE_CONSTANT (divisor) || integer_zerop (divisor)) | |
2459 | return true; | |
2460 | return false; | |
2461 | ||
2462 | case LT_EXPR: | |
2463 | case LE_EXPR: | |
2464 | case GT_EXPR: | |
2465 | case GE_EXPR: | |
2466 | case LTGT_EXPR: | |
2467 | /* Some floating point comparisons may trap. */ | |
2468 | return honor_nans; | |
2469 | ||
2470 | case EQ_EXPR: | |
2471 | case NE_EXPR: | |
2472 | case UNORDERED_EXPR: | |
2473 | case ORDERED_EXPR: | |
2474 | case UNLT_EXPR: | |
2475 | case UNLE_EXPR: | |
2476 | case UNGT_EXPR: | |
2477 | case UNGE_EXPR: | |
2478 | case UNEQ_EXPR: | |
2479 | return honor_snans; | |
2480 | ||
75a70cf9 | 2481 | case NEGATE_EXPR: |
2482 | case ABS_EXPR: | |
2483 | case CONJ_EXPR: | |
2484 | /* These operations don't trap with floating point. */ | |
2485 | if (honor_trapv) | |
2486 | return true; | |
2487 | return false; | |
2488 | ||
2489 | case PLUS_EXPR: | |
2490 | case MINUS_EXPR: | |
2491 | case MULT_EXPR: | |
2492 | /* Any floating arithmetic may trap. */ | |
2493 | if (fp_operation && flag_trapping_math) | |
2494 | return true; | |
2495 | if (honor_trapv) | |
2496 | return true; | |
2497 | return false; | |
2498 | ||
aa9d6f35 | 2499 | case COMPLEX_EXPR: |
2500 | case CONSTRUCTOR: | |
2501 | /* Constructing an object cannot trap. */ | |
2502 | return false; | |
2503 | ||
75a70cf9 | 2504 | default: |
2505 | /* Any floating arithmetic may trap. */ | |
2506 | if (fp_operation && flag_trapping_math) | |
2507 | return true; | |
2508 | ||
2509 | *handled = false; | |
2510 | return false; | |
2511 | } | |
2512 | } | |
2513 | ||
2514 | /* Return true if operation OP may trap. FP_OPERATION is true if OP is applied | |
2515 | on floating-point values. HONOR_TRAPV is true if OP is applied on integer | |
2516 | type operands that may trap. If OP is a division operator, DIVISOR contains | |
2517 | the value of the divisor. */ | |
2518 | ||
2519 | bool | |
2520 | operation_could_trap_p (enum tree_code op, bool fp_operation, bool honor_trapv, | |
2521 | tree divisor) | |
2522 | { | |
2523 | bool honor_nans = (fp_operation && flag_trapping_math | |
2524 | && !flag_finite_math_only); | |
2525 | bool honor_snans = fp_operation && flag_signaling_nans != 0; | |
2526 | bool handled; | |
2527 | ||
2528 | if (TREE_CODE_CLASS (op) != tcc_comparison | |
2529 | && TREE_CODE_CLASS (op) != tcc_unary | |
2530 | && TREE_CODE_CLASS (op) != tcc_binary) | |
2531 | return false; | |
2532 | ||
2533 | return operation_could_trap_helper_p (op, fp_operation, honor_trapv, | |
2534 | honor_nans, honor_snans, divisor, | |
2535 | &handled); | |
2536 | } | |
2537 | ||
0e80b01d | 2538 | |
2539 | /* Returns true if it is possible to prove that the index of | |
2540 | an array access REF (an ARRAY_REF expression) falls into the | |
2541 | array bounds. */ | |
2542 | ||
2543 | static bool | |
2544 | in_array_bounds_p (tree ref) | |
2545 | { | |
2546 | tree idx = TREE_OPERAND (ref, 1); | |
2547 | tree min, max; | |
2548 | ||
2549 | if (TREE_CODE (idx) != INTEGER_CST) | |
2550 | return false; | |
2551 | ||
2552 | min = array_ref_low_bound (ref); | |
2553 | max = array_ref_up_bound (ref); | |
2554 | if (!min | |
2555 | || !max | |
2556 | || TREE_CODE (min) != INTEGER_CST | |
2557 | || TREE_CODE (max) != INTEGER_CST) | |
2558 | return false; | |
2559 | ||
2560 | if (tree_int_cst_lt (idx, min) | |
2561 | || tree_int_cst_lt (max, idx)) | |
2562 | return false; | |
2563 | ||
2564 | return true; | |
2565 | } | |
2566 | ||
2567 | /* Returns true if it is possible to prove that the range of | |
2568 | an array access REF (an ARRAY_RANGE_REF expression) falls | |
2569 | into the array bounds. */ | |
2570 | ||
2571 | static bool | |
2572 | range_in_array_bounds_p (tree ref) | |
2573 | { | |
2574 | tree domain_type = TYPE_DOMAIN (TREE_TYPE (ref)); | |
2575 | tree range_min, range_max, min, max; | |
2576 | ||
2577 | range_min = TYPE_MIN_VALUE (domain_type); | |
2578 | range_max = TYPE_MAX_VALUE (domain_type); | |
2579 | if (!range_min | |
2580 | || !range_max | |
2581 | || TREE_CODE (range_min) != INTEGER_CST | |
2582 | || TREE_CODE (range_max) != INTEGER_CST) | |
2583 | return false; | |
2584 | ||
2585 | min = array_ref_low_bound (ref); | |
2586 | max = array_ref_up_bound (ref); | |
2587 | if (!min | |
2588 | || !max | |
2589 | || TREE_CODE (min) != INTEGER_CST | |
2590 | || TREE_CODE (max) != INTEGER_CST) | |
2591 | return false; | |
2592 | ||
2593 | if (tree_int_cst_lt (range_min, min) | |
2594 | || tree_int_cst_lt (max, range_max)) | |
2595 | return false; | |
2596 | ||
2597 | return true; | |
2598 | } | |
2599 | ||
75a70cf9 | 2600 | /* Return true if EXPR can trap, as in dereferencing an invalid pointer |
35c15734 | 2601 | location or floating point arithmetic. C.f. the rtl version, may_trap_p. |
2602 | This routine expects only GIMPLE lhs or rhs input. */ | |
4ee9c684 | 2603 | |
2604 | bool | |
2605 | tree_could_trap_p (tree expr) | |
2606 | { | |
75a70cf9 | 2607 | enum tree_code code; |
35c15734 | 2608 | bool fp_operation = false; |
db97ad41 | 2609 | bool honor_trapv = false; |
75a70cf9 | 2610 | tree t, base, div = NULL_TREE; |
4ee9c684 | 2611 | |
75a70cf9 | 2612 | if (!expr) |
2613 | return false; | |
e38def9c | 2614 | |
75a70cf9 | 2615 | code = TREE_CODE (expr); |
2616 | t = TREE_TYPE (expr); | |
2617 | ||
2618 | if (t) | |
35c15734 | 2619 | { |
7076cb5d | 2620 | if (COMPARISON_CLASS_P (expr)) |
2621 | fp_operation = FLOAT_TYPE_P (TREE_TYPE (TREE_OPERAND (expr, 0))); | |
2622 | else | |
2623 | fp_operation = FLOAT_TYPE_P (t); | |
75a70cf9 | 2624 | honor_trapv = INTEGRAL_TYPE_P (t) && TYPE_OVERFLOW_TRAPS (t); |
35c15734 | 2625 | } |
2626 | ||
75a70cf9 | 2627 | if (TREE_CODE_CLASS (code) == tcc_binary) |
2628 | div = TREE_OPERAND (expr, 1); | |
2629 | if (operation_could_trap_p (code, fp_operation, honor_trapv, div)) | |
2630 | return true; | |
2631 | ||
80f06481 | 2632 | restart: |
4ee9c684 | 2633 | switch (code) |
2634 | { | |
4ee9c684 | 2635 | case COMPONENT_REF: |
2636 | case REALPART_EXPR: | |
2637 | case IMAGPART_EXPR: | |
2638 | case BIT_FIELD_REF: | |
26d2ad79 | 2639 | case VIEW_CONVERT_EXPR: |
80f06481 | 2640 | case WITH_SIZE_EXPR: |
2641 | expr = TREE_OPERAND (expr, 0); | |
2642 | code = TREE_CODE (expr); | |
2643 | goto restart; | |
7d23383d | 2644 | |
2645 | case ARRAY_RANGE_REF: | |
2100c228 | 2646 | base = TREE_OPERAND (expr, 0); |
2647 | if (tree_could_trap_p (base)) | |
7d23383d | 2648 | return true; |
2100c228 | 2649 | if (TREE_THIS_NOTRAP (expr)) |
2650 | return false; | |
2100c228 | 2651 | return !range_in_array_bounds_p (expr); |
7d23383d | 2652 | |
2653 | case ARRAY_REF: | |
2654 | base = TREE_OPERAND (expr, 0); | |
7d23383d | 2655 | if (tree_could_trap_p (base)) |
2656 | return true; | |
7d23383d | 2657 | if (TREE_THIS_NOTRAP (expr)) |
2658 | return false; | |
7d23383d | 2659 | return !in_array_bounds_p (expr); |
4ee9c684 | 2660 | |
cdf2f9e4 | 2661 | case TARGET_MEM_REF: |
182cf5a9 | 2662 | case MEM_REF: |
cdf2f9e4 | 2663 | if (TREE_CODE (TREE_OPERAND (expr, 0)) == ADDR_EXPR |
2664 | && tree_could_trap_p (TREE_OPERAND (TREE_OPERAND (expr, 0), 0))) | |
2665 | return true; | |
2666 | if (TREE_THIS_NOTRAP (expr)) | |
182cf5a9 | 2667 | return false; |
cdf2f9e4 | 2668 | /* We cannot prove that the access is in-bounds when we have |
2669 | variable-index TARGET_MEM_REFs. */ | |
2670 | if (code == TARGET_MEM_REF | |
2671 | && (TMR_INDEX (expr) || TMR_INDEX2 (expr))) | |
2672 | return true; | |
2673 | if (TREE_CODE (TREE_OPERAND (expr, 0)) == ADDR_EXPR) | |
2674 | { | |
2675 | tree base = TREE_OPERAND (TREE_OPERAND (expr, 0), 0); | |
7f646368 | 2676 | offset_int off = mem_ref_offset (expr); |
2677 | if (wi::neg_p (off, SIGNED)) | |
cdf2f9e4 | 2678 | return true; |
2679 | if (TREE_CODE (base) == STRING_CST) | |
7f646368 | 2680 | return wi::leu_p (TREE_STRING_LENGTH (base), off); |
cdf2f9e4 | 2681 | else if (DECL_SIZE_UNIT (base) == NULL_TREE |
2682 | || TREE_CODE (DECL_SIZE_UNIT (base)) != INTEGER_CST | |
7f646368 | 2683 | || wi::leu_p (wi::to_offset (DECL_SIZE_UNIT (base)), off)) |
cdf2f9e4 | 2684 | return true; |
2685 | /* Now we are sure the first byte of the access is inside | |
2686 | the object. */ | |
2687 | return false; | |
2688 | } | |
2689 | return true; | |
2690 | ||
4ee9c684 | 2691 | case INDIRECT_REF: |
35c15734 | 2692 | return !TREE_THIS_NOTRAP (expr); |
2693 | ||
2694 | case ASM_EXPR: | |
2695 | return TREE_THIS_VOLATILE (expr); | |
010d0641 | 2696 | |
75a70cf9 | 2697 | case CALL_EXPR: |
2698 | t = get_callee_fndecl (expr); | |
2699 | /* Assume that calls to weak functions may trap. */ | |
7e49f1a1 | 2700 | if (!t || !DECL_P (t)) |
35c15734 | 2701 | return true; |
7e49f1a1 | 2702 | if (DECL_WEAK (t)) |
2703 | return tree_could_trap_p (t); | |
2704 | return false; | |
2705 | ||
2706 | case FUNCTION_DECL: | |
2707 | /* Assume that accesses to weak functions may trap, unless we know | |
2708 | they are certainly defined in current TU or in some other | |
2709 | LTO partition. */ | |
9427cf46 | 2710 | if (DECL_WEAK (expr) && !DECL_COMDAT (expr) && DECL_EXTERNAL (expr)) |
7e49f1a1 | 2711 | { |
9427cf46 | 2712 | cgraph_node *node = cgraph_node::get (expr); |
2713 | if (node) | |
2714 | node = node->function_symbol (); | |
2715 | return !(node && node->in_other_partition); | |
7e49f1a1 | 2716 | } |
2717 | return false; | |
2718 | ||
2719 | case VAR_DECL: | |
2720 | /* Assume that accesses to weak vars may trap, unless we know | |
2721 | they are certainly defined in current TU or in some other | |
2722 | LTO partition. */ | |
9427cf46 | 2723 | if (DECL_WEAK (expr) && !DECL_COMDAT (expr) && DECL_EXTERNAL (expr)) |
7e49f1a1 | 2724 | { |
9427cf46 | 2725 | varpool_node *node = varpool_node::get (expr); |
2726 | if (node) | |
2727 | node = node->ultimate_alias_target (); | |
2728 | return !(node && node->in_other_partition); | |
7e49f1a1 | 2729 | } |
35c15734 | 2730 | return false; |
2731 | ||
75a70cf9 | 2732 | default: |
2733 | return false; | |
2734 | } | |
2735 | } | |
35c15734 | 2736 | |
35c15734 | 2737 | |
75a70cf9 | 2738 | /* Helper for stmt_could_throw_p. Return true if STMT (assumed to be a |
2739 | an assignment or a conditional) may throw. */ | |
35c15734 | 2740 | |
75a70cf9 | 2741 | static bool |
2742 | stmt_could_throw_1_p (gimple stmt) | |
2743 | { | |
2744 | enum tree_code code = gimple_expr_code (stmt); | |
2745 | bool honor_nans = false; | |
2746 | bool honor_snans = false; | |
2747 | bool fp_operation = false; | |
2748 | bool honor_trapv = false; | |
2749 | tree t; | |
2750 | size_t i; | |
2751 | bool handled, ret; | |
db97ad41 | 2752 | |
75a70cf9 | 2753 | if (TREE_CODE_CLASS (code) == tcc_comparison |
2754 | || TREE_CODE_CLASS (code) == tcc_unary | |
2755 | || TREE_CODE_CLASS (code) == tcc_binary) | |
2756 | { | |
25f48be0 | 2757 | if (is_gimple_assign (stmt) |
2758 | && TREE_CODE_CLASS (code) == tcc_comparison) | |
2759 | t = TREE_TYPE (gimple_assign_rhs1 (stmt)); | |
2760 | else if (gimple_code (stmt) == GIMPLE_COND) | |
2761 | t = TREE_TYPE (gimple_cond_lhs (stmt)); | |
2762 | else | |
2763 | t = gimple_expr_type (stmt); | |
75a70cf9 | 2764 | fp_operation = FLOAT_TYPE_P (t); |
2765 | if (fp_operation) | |
2766 | { | |
2767 | honor_nans = flag_trapping_math && !flag_finite_math_only; | |
2768 | honor_snans = flag_signaling_nans != 0; | |
2769 | } | |
2770 | else if (INTEGRAL_TYPE_P (t) && TYPE_OVERFLOW_TRAPS (t)) | |
2771 | honor_trapv = true; | |
2772 | } | |
2773 | ||
2774 | /* Check if the main expression may trap. */ | |
2775 | t = is_gimple_assign (stmt) ? gimple_assign_rhs2 (stmt) : NULL; | |
2776 | ret = operation_could_trap_helper_p (code, fp_operation, honor_trapv, | |
2777 | honor_nans, honor_snans, t, | |
2778 | &handled); | |
2779 | if (handled) | |
2780 | return ret; | |
2781 | ||
2782 | /* If the expression does not trap, see if any of the individual operands may | |
2783 | trap. */ | |
2784 | for (i = 0; i < gimple_num_ops (stmt); i++) | |
2785 | if (tree_could_trap_p (gimple_op (stmt, i))) | |
2786 | return true; | |
2787 | ||
2788 | return false; | |
2789 | } | |
2790 | ||
2791 | ||
2792 | /* Return true if statement STMT could throw an exception. */ | |
2793 | ||
2794 | bool | |
2795 | stmt_could_throw_p (gimple stmt) | |
2796 | { | |
75a70cf9 | 2797 | if (!flag_exceptions) |
2798 | return false; | |
2799 | ||
2800 | /* The only statements that can throw an exception are assignments, | |
e38def9c | 2801 | conditionals, calls, resx, and asms. */ |
2802 | switch (gimple_code (stmt)) | |
2803 | { | |
2804 | case GIMPLE_RESX: | |
2805 | return true; | |
75a70cf9 | 2806 | |
e38def9c | 2807 | case GIMPLE_CALL: |
1a91d914 | 2808 | return !gimple_call_nothrow_p (as_a <gcall *> (stmt)); |
75a70cf9 | 2809 | |
e38def9c | 2810 | case GIMPLE_ASSIGN: |
2811 | case GIMPLE_COND: | |
cbeb677e | 2812 | if (!cfun->can_throw_non_call_exceptions) |
e38def9c | 2813 | return false; |
2814 | return stmt_could_throw_1_p (stmt); | |
75a70cf9 | 2815 | |
e38def9c | 2816 | case GIMPLE_ASM: |
cbeb677e | 2817 | if (!cfun->can_throw_non_call_exceptions) |
e38def9c | 2818 | return false; |
1a91d914 | 2819 | return gimple_asm_volatile_p (as_a <gasm *> (stmt)); |
e38def9c | 2820 | |
2821 | default: | |
2822 | return false; | |
2823 | } | |
4ee9c684 | 2824 | } |
2825 | ||
75a70cf9 | 2826 | |
2827 | /* Return true if expression T could throw an exception. */ | |
2828 | ||
4ee9c684 | 2829 | bool |
2830 | tree_could_throw_p (tree t) | |
2831 | { | |
2832 | if (!flag_exceptions) | |
2833 | return false; | |
75a70cf9 | 2834 | if (TREE_CODE (t) == MODIFY_EXPR) |
4ee9c684 | 2835 | { |
cbeb677e | 2836 | if (cfun->can_throw_non_call_exceptions |
e38def9c | 2837 | && tree_could_trap_p (TREE_OPERAND (t, 0))) |
2838 | return true; | |
75a70cf9 | 2839 | t = TREE_OPERAND (t, 1); |
4ee9c684 | 2840 | } |
2841 | ||
80f06481 | 2842 | if (TREE_CODE (t) == WITH_SIZE_EXPR) |
2843 | t = TREE_OPERAND (t, 0); | |
4ee9c684 | 2844 | if (TREE_CODE (t) == CALL_EXPR) |
2845 | return (call_expr_flags (t) & ECF_NOTHROW) == 0; | |
cbeb677e | 2846 | if (cfun->can_throw_non_call_exceptions) |
3864ad30 | 2847 | return tree_could_trap_p (t); |
4ee9c684 | 2848 | return false; |
2849 | } | |
2850 | ||
b5cebd44 | 2851 | /* Return true if STMT can throw an exception that is not caught within |
2852 | the current function (CFUN). */ | |
2853 | ||
2854 | bool | |
2855 | stmt_can_throw_external (gimple stmt) | |
2856 | { | |
e38def9c | 2857 | int lp_nr; |
b5cebd44 | 2858 | |
2859 | if (!stmt_could_throw_p (stmt)) | |
2860 | return false; | |
2861 | ||
e38def9c | 2862 | lp_nr = lookup_stmt_eh_lp (stmt); |
2863 | return lp_nr == 0; | |
b5cebd44 | 2864 | } |
75a70cf9 | 2865 | |
2866 | /* Return true if STMT can throw an exception that is caught within | |
2867 | the current function (CFUN). */ | |
2868 | ||
4ee9c684 | 2869 | bool |
75a70cf9 | 2870 | stmt_can_throw_internal (gimple stmt) |
4ee9c684 | 2871 | { |
e38def9c | 2872 | int lp_nr; |
75a70cf9 | 2873 | |
e38def9c | 2874 | if (!stmt_could_throw_p (stmt)) |
4ee9c684 | 2875 | return false; |
75a70cf9 | 2876 | |
e38def9c | 2877 | lp_nr = lookup_stmt_eh_lp (stmt); |
2878 | return lp_nr > 0; | |
2879 | } | |
2880 | ||
2881 | /* Given a statement STMT in IFUN, if STMT can no longer throw, then | |
2882 | remove any entry it might have from the EH table. Return true if | |
2883 | any change was made. */ | |
2884 | ||
2885 | bool | |
2886 | maybe_clean_eh_stmt_fn (struct function *ifun, gimple stmt) | |
2887 | { | |
2888 | if (stmt_could_throw_p (stmt)) | |
2889 | return false; | |
2890 | return remove_stmt_from_eh_lp_fn (ifun, stmt); | |
4ee9c684 | 2891 | } |
2892 | ||
e38def9c | 2893 | /* Likewise, but always use the current function. */ |
2894 | ||
2895 | bool | |
2896 | maybe_clean_eh_stmt (gimple stmt) | |
2897 | { | |
2898 | return maybe_clean_eh_stmt_fn (cfun, stmt); | |
2899 | } | |
4ee9c684 | 2900 | |
4c27dd45 | 2901 | /* Given a statement OLD_STMT and a new statement NEW_STMT that has replaced |
2902 | OLD_STMT in the function, remove OLD_STMT from the EH table and put NEW_STMT | |
2903 | in the table if it should be in there. Return TRUE if a replacement was | |
2904 | done that my require an EH edge purge. */ | |
2905 | ||
e38def9c | 2906 | bool |
2907 | maybe_clean_or_replace_eh_stmt (gimple old_stmt, gimple new_stmt) | |
35c15734 | 2908 | { |
e38def9c | 2909 | int lp_nr = lookup_stmt_eh_lp (old_stmt); |
4c27dd45 | 2910 | |
e38def9c | 2911 | if (lp_nr != 0) |
4c27dd45 | 2912 | { |
75a70cf9 | 2913 | bool new_stmt_could_throw = stmt_could_throw_p (new_stmt); |
4c27dd45 | 2914 | |
2915 | if (new_stmt == old_stmt && new_stmt_could_throw) | |
2916 | return false; | |
2917 | ||
e38def9c | 2918 | remove_stmt_from_eh_lp (old_stmt); |
4c27dd45 | 2919 | if (new_stmt_could_throw) |
2920 | { | |
e38def9c | 2921 | add_stmt_to_eh_lp (new_stmt, lp_nr); |
4c27dd45 | 2922 | return false; |
2923 | } | |
2924 | else | |
2925 | return true; | |
2926 | } | |
2927 | ||
35c15734 | 2928 | return false; |
2929 | } | |
e38def9c | 2930 | |
9d75589a | 2931 | /* Given a statement OLD_STMT in OLD_FUN and a duplicate statement NEW_STMT |
e38def9c | 2932 | in NEW_FUN, copy the EH table data from OLD_STMT to NEW_STMT. The MAP |
2933 | operand is the return value of duplicate_eh_regions. */ | |
2934 | ||
2935 | bool | |
2936 | maybe_duplicate_eh_stmt_fn (struct function *new_fun, gimple new_stmt, | |
2937 | struct function *old_fun, gimple old_stmt, | |
06ecf488 | 2938 | hash_map<void *, void *> *map, |
2939 | int default_lp_nr) | |
e38def9c | 2940 | { |
2941 | int old_lp_nr, new_lp_nr; | |
e38def9c | 2942 | |
2943 | if (!stmt_could_throw_p (new_stmt)) | |
2944 | return false; | |
2945 | ||
2946 | old_lp_nr = lookup_stmt_eh_lp_fn (old_fun, old_stmt); | |
2947 | if (old_lp_nr == 0) | |
2948 | { | |
2949 | if (default_lp_nr == 0) | |
2950 | return false; | |
2951 | new_lp_nr = default_lp_nr; | |
2952 | } | |
2953 | else if (old_lp_nr > 0) | |
2954 | { | |
2955 | eh_landing_pad old_lp, new_lp; | |
2956 | ||
f1f41a6c | 2957 | old_lp = (*old_fun->eh->lp_array)[old_lp_nr]; |
06ecf488 | 2958 | new_lp = static_cast<eh_landing_pad> (*map->get (old_lp)); |
e38def9c | 2959 | new_lp_nr = new_lp->index; |
2960 | } | |
2961 | else | |
2962 | { | |
2963 | eh_region old_r, new_r; | |
2964 | ||
f1f41a6c | 2965 | old_r = (*old_fun->eh->region_array)[-old_lp_nr]; |
06ecf488 | 2966 | new_r = static_cast<eh_region> (*map->get (old_r)); |
e38def9c | 2967 | new_lp_nr = -new_r->index; |
2968 | } | |
2969 | ||
2970 | add_stmt_to_eh_lp_fn (new_fun, new_stmt, new_lp_nr); | |
2971 | return true; | |
2972 | } | |
2973 | ||
2974 | /* Similar, but both OLD_STMT and NEW_STMT are within the current function, | |
2975 | and thus no remapping is required. */ | |
2976 | ||
2977 | bool | |
2978 | maybe_duplicate_eh_stmt (gimple new_stmt, gimple old_stmt) | |
2979 | { | |
2980 | int lp_nr; | |
2981 | ||
2982 | if (!stmt_could_throw_p (new_stmt)) | |
2983 | return false; | |
2984 | ||
2985 | lp_nr = lookup_stmt_eh_lp (old_stmt); | |
2986 | if (lp_nr == 0) | |
2987 | return false; | |
2988 | ||
2989 | add_stmt_to_eh_lp (new_stmt, lp_nr); | |
2990 | return true; | |
2991 | } | |
4888ab9a | 2992 | \f |
75a70cf9 | 2993 | /* Returns TRUE if oneh and twoh are exception handlers (gimple_try_cleanup of |
2994 | GIMPLE_TRY) that are similar enough to be considered the same. Currently | |
2995 | this only handles handlers consisting of a single call, as that's the | |
2996 | important case for C++: a destructor call for a particular object showing | |
2997 | up in multiple handlers. */ | |
4888ab9a | 2998 | |
2999 | static bool | |
75a70cf9 | 3000 | same_handler_p (gimple_seq oneh, gimple_seq twoh) |
4888ab9a | 3001 | { |
75a70cf9 | 3002 | gimple_stmt_iterator gsi; |
3003 | gimple ones, twos; | |
3004 | unsigned int ai; | |
4888ab9a | 3005 | |
75a70cf9 | 3006 | gsi = gsi_start (oneh); |
3007 | if (!gsi_one_before_end_p (gsi)) | |
4888ab9a | 3008 | return false; |
75a70cf9 | 3009 | ones = gsi_stmt (gsi); |
4888ab9a | 3010 | |
75a70cf9 | 3011 | gsi = gsi_start (twoh); |
3012 | if (!gsi_one_before_end_p (gsi)) | |
4888ab9a | 3013 | return false; |
75a70cf9 | 3014 | twos = gsi_stmt (gsi); |
3015 | ||
3016 | if (!is_gimple_call (ones) | |
3017 | || !is_gimple_call (twos) | |
3018 | || gimple_call_lhs (ones) | |
3019 | || gimple_call_lhs (twos) | |
3020 | || gimple_call_chain (ones) | |
3021 | || gimple_call_chain (twos) | |
fb049fba | 3022 | || !gimple_call_same_target_p (ones, twos) |
75a70cf9 | 3023 | || gimple_call_num_args (ones) != gimple_call_num_args (twos)) |
4888ab9a | 3024 | return false; |
3025 | ||
75a70cf9 | 3026 | for (ai = 0; ai < gimple_call_num_args (ones); ++ai) |
3027 | if (!operand_equal_p (gimple_call_arg (ones, ai), | |
e38def9c | 3028 | gimple_call_arg (twos, ai), 0)) |
4888ab9a | 3029 | return false; |
3030 | ||
3031 | return true; | |
3032 | } | |
3033 | ||
3034 | /* Optimize | |
3035 | try { A() } finally { try { ~B() } catch { ~A() } } | |
3036 | try { ... } finally { ~A() } | |
3037 | into | |
3038 | try { A() } catch { ~B() } | |
3039 | try { ~B() ... } finally { ~A() } | |
3040 | ||
3041 | This occurs frequently in C++, where A is a local variable and B is a | |
3042 | temporary used in the initializer for A. */ | |
3043 | ||
3044 | static void | |
1a91d914 | 3045 | optimize_double_finally (gtry *one, gtry *two) |
4888ab9a | 3046 | { |
75a70cf9 | 3047 | gimple oneh; |
3048 | gimple_stmt_iterator gsi; | |
e3a19533 | 3049 | gimple_seq cleanup; |
4888ab9a | 3050 | |
e3a19533 | 3051 | cleanup = gimple_try_cleanup (one); |
3052 | gsi = gsi_start (cleanup); | |
75a70cf9 | 3053 | if (!gsi_one_before_end_p (gsi)) |
4888ab9a | 3054 | return; |
3055 | ||
75a70cf9 | 3056 | oneh = gsi_stmt (gsi); |
3057 | if (gimple_code (oneh) != GIMPLE_TRY | |
3058 | || gimple_try_kind (oneh) != GIMPLE_TRY_CATCH) | |
4888ab9a | 3059 | return; |
3060 | ||
75a70cf9 | 3061 | if (same_handler_p (gimple_try_cleanup (oneh), gimple_try_cleanup (two))) |
4888ab9a | 3062 | { |
75a70cf9 | 3063 | gimple_seq seq = gimple_try_eval (oneh); |
4888ab9a | 3064 | |
75a70cf9 | 3065 | gimple_try_set_cleanup (one, seq); |
3066 | gimple_try_set_kind (one, GIMPLE_TRY_CATCH); | |
3067 | seq = copy_gimple_seq_and_replace_locals (seq); | |
3068 | gimple_seq_add_seq (&seq, gimple_try_eval (two)); | |
3069 | gimple_try_set_eval (two, seq); | |
4888ab9a | 3070 | } |
3071 | } | |
3072 | ||
3073 | /* Perform EH refactoring optimizations that are simpler to do when code | |
c7684b8e | 3074 | flow has been lowered but EH structures haven't. */ |
4888ab9a | 3075 | |
3076 | static void | |
75a70cf9 | 3077 | refactor_eh_r (gimple_seq seq) |
4888ab9a | 3078 | { |
75a70cf9 | 3079 | gimple_stmt_iterator gsi; |
3080 | gimple one, two; | |
4888ab9a | 3081 | |
75a70cf9 | 3082 | one = NULL; |
3083 | two = NULL; | |
3084 | gsi = gsi_start (seq); | |
3085 | while (1) | |
3086 | { | |
3087 | one = two; | |
3088 | if (gsi_end_p (gsi)) | |
3089 | two = NULL; | |
3090 | else | |
3091 | two = gsi_stmt (gsi); | |
1a91d914 | 3092 | if (one && two) |
3093 | if (gtry *try_one = dyn_cast <gtry *> (one)) | |
3094 | if (gtry *try_two = dyn_cast <gtry *> (two)) | |
3095 | if (gimple_try_kind (try_one) == GIMPLE_TRY_FINALLY | |
3096 | && gimple_try_kind (try_two) == GIMPLE_TRY_FINALLY) | |
3097 | optimize_double_finally (try_one, try_two); | |
75a70cf9 | 3098 | if (one) |
3099 | switch (gimple_code (one)) | |
4888ab9a | 3100 | { |
75a70cf9 | 3101 | case GIMPLE_TRY: |
3102 | refactor_eh_r (gimple_try_eval (one)); | |
3103 | refactor_eh_r (gimple_try_cleanup (one)); | |
3104 | break; | |
3105 | case GIMPLE_CATCH: | |
1a91d914 | 3106 | refactor_eh_r (gimple_catch_handler (as_a <gcatch *> (one))); |
75a70cf9 | 3107 | break; |
3108 | case GIMPLE_EH_FILTER: | |
3109 | refactor_eh_r (gimple_eh_filter_failure (one)); | |
3110 | break; | |
4c0315d0 | 3111 | case GIMPLE_EH_ELSE: |
1a91d914 | 3112 | { |
3113 | geh_else *eh_else_stmt = as_a <geh_else *> (one); | |
3114 | refactor_eh_r (gimple_eh_else_n_body (eh_else_stmt)); | |
3115 | refactor_eh_r (gimple_eh_else_e_body (eh_else_stmt)); | |
3116 | } | |
4c0315d0 | 3117 | break; |
75a70cf9 | 3118 | default: |
3119 | break; | |
4888ab9a | 3120 | } |
75a70cf9 | 3121 | if (two) |
3122 | gsi_next (&gsi); | |
3123 | else | |
3124 | break; | |
4888ab9a | 3125 | } |
3126 | } | |
3127 | ||
cbe8bda8 | 3128 | namespace { |
3129 | ||
3130 | const pass_data pass_data_refactor_eh = | |
4888ab9a | 3131 | { |
cbe8bda8 | 3132 | GIMPLE_PASS, /* type */ |
3133 | "ehopt", /* name */ | |
3134 | OPTGROUP_NONE, /* optinfo_flags */ | |
cbe8bda8 | 3135 | TV_TREE_EH, /* tv_id */ |
3136 | PROP_gimple_lcf, /* properties_required */ | |
3137 | 0, /* properties_provided */ | |
3138 | 0, /* properties_destroyed */ | |
3139 | 0, /* todo_flags_start */ | |
3140 | 0, /* todo_flags_finish */ | |
4888ab9a | 3141 | }; |
cbe8bda8 | 3142 | |
3143 | class pass_refactor_eh : public gimple_opt_pass | |
3144 | { | |
3145 | public: | |
9af5ce0c | 3146 | pass_refactor_eh (gcc::context *ctxt) |
3147 | : gimple_opt_pass (pass_data_refactor_eh, ctxt) | |
cbe8bda8 | 3148 | {} |
3149 | ||
3150 | /* opt_pass methods: */ | |
31315c24 | 3151 | virtual bool gate (function *) { return flag_exceptions != 0; } |
65b0537f | 3152 | virtual unsigned int execute (function *) |
3153 | { | |
3154 | refactor_eh_r (gimple_body (current_function_decl)); | |
3155 | return 0; | |
3156 | } | |
cbe8bda8 | 3157 | |
3158 | }; // class pass_refactor_eh | |
3159 | ||
3160 | } // anon namespace | |
3161 | ||
3162 | gimple_opt_pass * | |
3163 | make_pass_refactor_eh (gcc::context *ctxt) | |
3164 | { | |
3165 | return new pass_refactor_eh (ctxt); | |
3166 | } | |
e38def9c | 3167 | \f |
3168 | /* At the end of gimple optimization, we can lower RESX. */ | |
4c5fcca6 | 3169 | |
e38def9c | 3170 | static bool |
1a91d914 | 3171 | lower_resx (basic_block bb, gresx *stmt, |
3172 | hash_map<eh_region, tree> *mnt_map) | |
4c5fcca6 | 3173 | { |
e38def9c | 3174 | int lp_nr; |
3175 | eh_region src_r, dst_r; | |
3176 | gimple_stmt_iterator gsi; | |
3177 | gimple x; | |
3178 | tree fn, src_nr; | |
3179 | bool ret = false; | |
4c5fcca6 | 3180 | |
e38def9c | 3181 | lp_nr = lookup_stmt_eh_lp (stmt); |
3182 | if (lp_nr != 0) | |
3183 | dst_r = get_eh_region_from_lp_number (lp_nr); | |
3184 | else | |
3185 | dst_r = NULL; | |
4c5fcca6 | 3186 | |
e38def9c | 3187 | src_r = get_eh_region_from_number (gimple_resx_region (stmt)); |
e38def9c | 3188 | gsi = gsi_last_bb (bb); |
4c5fcca6 | 3189 | |
395fc2bb | 3190 | if (src_r == NULL) |
3191 | { | |
3192 | /* We can wind up with no source region when pass_cleanup_eh shows | |
3193 | that there are no entries into an eh region and deletes it, but | |
3194 | then the block that contains the resx isn't removed. This can | |
3195 | happen without optimization when the switch statement created by | |
3196 | lower_try_finally_switch isn't simplified to remove the eh case. | |
3197 | ||
3198 | Resolve this by expanding the resx node to an abort. */ | |
3199 | ||
b9a16870 | 3200 | fn = builtin_decl_implicit (BUILT_IN_TRAP); |
395fc2bb | 3201 | x = gimple_build_call (fn, 0); |
3202 | gsi_insert_before (&gsi, x, GSI_SAME_STMT); | |
3203 | ||
3204 | while (EDGE_COUNT (bb->succs) > 0) | |
3205 | remove_edge (EDGE_SUCC (bb, 0)); | |
3206 | } | |
3207 | else if (dst_r) | |
e38def9c | 3208 | { |
3209 | /* When we have a destination region, we resolve this by copying | |
3210 | the excptr and filter values into place, and changing the edge | |
3211 | to immediately after the landing pad. */ | |
3212 | edge e; | |
4c5fcca6 | 3213 | |
e38def9c | 3214 | if (lp_nr < 0) |
3215 | { | |
3216 | basic_block new_bb; | |
e38def9c | 3217 | tree lab; |
3d1eacdb | 3218 | |
e38def9c | 3219 | /* We are resuming into a MUST_NOT_CALL region. Expand a call to |
3220 | the failure decl into a new block, if needed. */ | |
3221 | gcc_assert (dst_r->type == ERT_MUST_NOT_THROW); | |
4c5fcca6 | 3222 | |
06ecf488 | 3223 | tree *slot = mnt_map->get (dst_r); |
e38def9c | 3224 | if (slot == NULL) |
3225 | { | |
3226 | gimple_stmt_iterator gsi2; | |
4c5fcca6 | 3227 | |
e38def9c | 3228 | new_bb = create_empty_bb (bb); |
b3083327 | 3229 | add_bb_to_loop (new_bb, bb->loop_father); |
e38def9c | 3230 | lab = gimple_block_label (new_bb); |
3231 | gsi2 = gsi_start_bb (new_bb); | |
4c5fcca6 | 3232 | |
e38def9c | 3233 | fn = dst_r->u.must_not_throw.failure_decl; |
3234 | x = gimple_build_call (fn, 0); | |
3235 | gimple_set_location (x, dst_r->u.must_not_throw.failure_loc); | |
3236 | gsi_insert_after (&gsi2, x, GSI_CONTINUE_LINKING); | |
3bd82487 | 3237 | |
06ecf488 | 3238 | mnt_map->put (dst_r, lab); |
e38def9c | 3239 | } |
3240 | else | |
3241 | { | |
06ecf488 | 3242 | lab = *slot; |
e38def9c | 3243 | new_bb = label_to_block (lab); |
3244 | } | |
4c5fcca6 | 3245 | |
e38def9c | 3246 | gcc_assert (EDGE_COUNT (bb->succs) == 0); |
3247 | e = make_edge (bb, new_bb, EDGE_FALLTHRU); | |
3248 | e->count = bb->count; | |
3249 | e->probability = REG_BR_PROB_BASE; | |
3250 | } | |
3251 | else | |
3252 | { | |
3253 | edge_iterator ei; | |
bad12c62 | 3254 | tree dst_nr = build_int_cst (integer_type_node, dst_r->index); |
4c5fcca6 | 3255 | |
b9a16870 | 3256 | fn = builtin_decl_implicit (BUILT_IN_EH_COPY_VALUES); |
bad12c62 | 3257 | src_nr = build_int_cst (integer_type_node, src_r->index); |
e38def9c | 3258 | x = gimple_build_call (fn, 2, dst_nr, src_nr); |
3259 | gsi_insert_before (&gsi, x, GSI_SAME_STMT); | |
4c5fcca6 | 3260 | |
e38def9c | 3261 | /* Update the flags for the outgoing edge. */ |
3262 | e = single_succ_edge (bb); | |
3263 | gcc_assert (e->flags & EDGE_EH); | |
3264 | e->flags = (e->flags & ~EDGE_EH) | EDGE_FALLTHRU; | |
4c5fcca6 | 3265 | |
e38def9c | 3266 | /* If there are no more EH users of the landing pad, delete it. */ |
3267 | FOR_EACH_EDGE (e, ei, e->dest->preds) | |
3268 | if (e->flags & EDGE_EH) | |
3269 | break; | |
3270 | if (e == NULL) | |
3271 | { | |
3272 | eh_landing_pad lp = get_eh_landing_pad_from_number (lp_nr); | |
3273 | remove_eh_landing_pad (lp); | |
3274 | } | |
3275 | } | |
4c5fcca6 | 3276 | |
e38def9c | 3277 | ret = true; |
3278 | } | |
3279 | else | |
3280 | { | |
3281 | tree var; | |
4c5fcca6 | 3282 | |
e38def9c | 3283 | /* When we don't have a destination region, this exception escapes |
3284 | up the call chain. We resolve this by generating a call to the | |
3285 | _Unwind_Resume library function. */ | |
4c5fcca6 | 3286 | |
471eff36 | 3287 | /* The ARM EABI redefines _Unwind_Resume as __cxa_end_cleanup |
e38def9c | 3288 | with no arguments for C++ and Java. Check for that. */ |
471eff36 | 3289 | if (src_r->use_cxa_end_cleanup) |
3290 | { | |
b9a16870 | 3291 | fn = builtin_decl_implicit (BUILT_IN_CXA_END_CLEANUP); |
471eff36 | 3292 | x = gimple_build_call (fn, 0); |
3293 | gsi_insert_before (&gsi, x, GSI_SAME_STMT); | |
3294 | } | |
3295 | else | |
3bd82487 | 3296 | { |
b9a16870 | 3297 | fn = builtin_decl_implicit (BUILT_IN_EH_POINTER); |
bad12c62 | 3298 | src_nr = build_int_cst (integer_type_node, src_r->index); |
e38def9c | 3299 | x = gimple_build_call (fn, 1, src_nr); |
f9e245b2 | 3300 | var = create_tmp_var (ptr_type_node); |
e38def9c | 3301 | var = make_ssa_name (var, x); |
3302 | gimple_call_set_lhs (x, var); | |
3303 | gsi_insert_before (&gsi, x, GSI_SAME_STMT); | |
3304 | ||
b9a16870 | 3305 | fn = builtin_decl_implicit (BUILT_IN_UNWIND_RESUME); |
e38def9c | 3306 | x = gimple_build_call (fn, 1, var); |
3307 | gsi_insert_before (&gsi, x, GSI_SAME_STMT); | |
3bd82487 | 3308 | } |
4c5fcca6 | 3309 | |
e38def9c | 3310 | gcc_assert (EDGE_COUNT (bb->succs) == 0); |
3bd82487 | 3311 | } |
3d1eacdb | 3312 | |
e38def9c | 3313 | gsi_remove (&gsi, true); |
3314 | ||
3315 | return ret; | |
3bd82487 | 3316 | } |
3317 | ||
cbe8bda8 | 3318 | namespace { |
3319 | ||
3320 | const pass_data pass_data_lower_resx = | |
3bd82487 | 3321 | { |
cbe8bda8 | 3322 | GIMPLE_PASS, /* type */ |
3323 | "resx", /* name */ | |
3324 | OPTGROUP_NONE, /* optinfo_flags */ | |
cbe8bda8 | 3325 | TV_TREE_EH, /* tv_id */ |
3326 | PROP_gimple_lcf, /* properties_required */ | |
3327 | 0, /* properties_provided */ | |
3328 | 0, /* properties_destroyed */ | |
3329 | 0, /* todo_flags_start */ | |
8b88439e | 3330 | 0, /* todo_flags_finish */ |
3bd82487 | 3331 | }; |
3332 | ||
cbe8bda8 | 3333 | class pass_lower_resx : public gimple_opt_pass |
3334 | { | |
3335 | public: | |
9af5ce0c | 3336 | pass_lower_resx (gcc::context *ctxt) |
3337 | : gimple_opt_pass (pass_data_lower_resx, ctxt) | |
cbe8bda8 | 3338 | {} |
3339 | ||
3340 | /* opt_pass methods: */ | |
31315c24 | 3341 | virtual bool gate (function *) { return flag_exceptions != 0; } |
65b0537f | 3342 | virtual unsigned int execute (function *); |
cbe8bda8 | 3343 | |
3344 | }; // class pass_lower_resx | |
3345 | ||
65b0537f | 3346 | unsigned |
3347 | pass_lower_resx::execute (function *fun) | |
e38def9c | 3348 | { |
3349 | basic_block bb; | |
e38def9c | 3350 | bool dominance_invalidated = false; |
3351 | bool any_rewritten = false; | |
3bd82487 | 3352 | |
06ecf488 | 3353 | hash_map<eh_region, tree> mnt_map; |
3bd82487 | 3354 | |
65b0537f | 3355 | FOR_EACH_BB_FN (bb, fun) |
e38def9c | 3356 | { |
3357 | gimple last = last_stmt (bb); | |
3358 | if (last && is_gimple_resx (last)) | |
3359 | { | |
1a91d914 | 3360 | dominance_invalidated |= |
3361 | lower_resx (bb, as_a <gresx *> (last), &mnt_map); | |
e38def9c | 3362 | any_rewritten = true; |
3363 | } | |
3364 | } | |
3365 | ||
e38def9c | 3366 | if (dominance_invalidated) |
3367 | { | |
3368 | free_dominance_info (CDI_DOMINATORS); | |
3369 | free_dominance_info (CDI_POST_DOMINATORS); | |
3bd82487 | 3370 | } |
4c5fcca6 | 3371 | |
e38def9c | 3372 | return any_rewritten ? TODO_update_ssa_only_virtuals : 0; |
3373 | } | |
4c5fcca6 | 3374 | |
cbe8bda8 | 3375 | } // anon namespace |
3376 | ||
3377 | gimple_opt_pass * | |
3378 | make_pass_lower_resx (gcc::context *ctxt) | |
3379 | { | |
3380 | return new pass_lower_resx (ctxt); | |
3381 | } | |
3382 | ||
1227a337 | 3383 | /* Try to optimize var = {v} {CLOBBER} stmts followed just by |
3384 | external throw. */ | |
3385 | ||
3386 | static void | |
3387 | optimize_clobbers (basic_block bb) | |
3388 | { | |
3389 | gimple_stmt_iterator gsi = gsi_last_bb (bb); | |
896a0c42 | 3390 | bool any_clobbers = false; |
3391 | bool seen_stack_restore = false; | |
3392 | edge_iterator ei; | |
3393 | edge e; | |
3394 | ||
3395 | /* Only optimize anything if the bb contains at least one clobber, | |
3396 | ends with resx (checked by caller), optionally contains some | |
3397 | debug stmts or labels, or at most one __builtin_stack_restore | |
3398 | call, and has an incoming EH edge. */ | |
d1d905ee | 3399 | for (gsi_prev (&gsi); !gsi_end_p (gsi); gsi_prev (&gsi)) |
1227a337 | 3400 | { |
3401 | gimple stmt = gsi_stmt (gsi); | |
3402 | if (is_gimple_debug (stmt)) | |
d1d905ee | 3403 | continue; |
896a0c42 | 3404 | if (gimple_clobber_p (stmt)) |
3405 | { | |
3406 | any_clobbers = true; | |
3407 | continue; | |
3408 | } | |
3409 | if (!seen_stack_restore | |
3410 | && gimple_call_builtin_p (stmt, BUILT_IN_STACK_RESTORE)) | |
3411 | { | |
3412 | seen_stack_restore = true; | |
3413 | continue; | |
3414 | } | |
3415 | if (gimple_code (stmt) == GIMPLE_LABEL) | |
3416 | break; | |
3417 | return; | |
3418 | } | |
3419 | if (!any_clobbers) | |
3420 | return; | |
3421 | FOR_EACH_EDGE (e, ei, bb->preds) | |
3422 | if (e->flags & EDGE_EH) | |
3423 | break; | |
3424 | if (e == NULL) | |
3425 | return; | |
3426 | gsi = gsi_last_bb (bb); | |
3427 | for (gsi_prev (&gsi); !gsi_end_p (gsi); gsi_prev (&gsi)) | |
3428 | { | |
3429 | gimple stmt = gsi_stmt (gsi); | |
3430 | if (!gimple_clobber_p (stmt)) | |
3431 | continue; | |
1227a337 | 3432 | unlink_stmt_vdef (stmt); |
3433 | gsi_remove (&gsi, true); | |
3434 | release_defs (stmt); | |
3435 | } | |
3436 | } | |
e38def9c | 3437 | |
07428872 | 3438 | /* Try to sink var = {v} {CLOBBER} stmts followed just by |
3439 | internal throw to successor BB. */ | |
3440 | ||
3441 | static int | |
3442 | sink_clobbers (basic_block bb) | |
3443 | { | |
3444 | edge e; | |
3445 | edge_iterator ei; | |
3446 | gimple_stmt_iterator gsi, dgsi; | |
3447 | basic_block succbb; | |
3448 | bool any_clobbers = false; | |
8aacb2c5 | 3449 | unsigned todo = 0; |
07428872 | 3450 | |
3451 | /* Only optimize if BB has a single EH successor and | |
3452 | all predecessor edges are EH too. */ | |
3453 | if (!single_succ_p (bb) | |
3454 | || (single_succ_edge (bb)->flags & EDGE_EH) == 0) | |
3455 | return 0; | |
3456 | ||
3457 | FOR_EACH_EDGE (e, ei, bb->preds) | |
3458 | { | |
3459 | if ((e->flags & EDGE_EH) == 0) | |
3460 | return 0; | |
3461 | } | |
3462 | ||
3463 | /* And BB contains only CLOBBER stmts before the final | |
3464 | RESX. */ | |
3465 | gsi = gsi_last_bb (bb); | |
3466 | for (gsi_prev (&gsi); !gsi_end_p (gsi); gsi_prev (&gsi)) | |
3467 | { | |
3468 | gimple stmt = gsi_stmt (gsi); | |
3469 | if (is_gimple_debug (stmt)) | |
3470 | continue; | |
3471 | if (gimple_code (stmt) == GIMPLE_LABEL) | |
3472 | break; | |
896a0c42 | 3473 | if (!gimple_clobber_p (stmt)) |
07428872 | 3474 | return 0; |
3475 | any_clobbers = true; | |
3476 | } | |
3477 | if (!any_clobbers) | |
3478 | return 0; | |
3479 | ||
0ba38440 | 3480 | edge succe = single_succ_edge (bb); |
3481 | succbb = succe->dest; | |
3482 | ||
3483 | /* See if there is a virtual PHI node to take an updated virtual | |
3484 | operand from. */ | |
1a91d914 | 3485 | gphi *vphi = NULL; |
0ba38440 | 3486 | tree vuse = NULL_TREE; |
1a91d914 | 3487 | for (gphi_iterator gpi = gsi_start_phis (succbb); |
3488 | !gsi_end_p (gpi); gsi_next (&gpi)) | |
0ba38440 | 3489 | { |
1a91d914 | 3490 | tree res = gimple_phi_result (gpi.phi ()); |
0ba38440 | 3491 | if (virtual_operand_p (res)) |
3492 | { | |
1a91d914 | 3493 | vphi = gpi.phi (); |
0ba38440 | 3494 | vuse = res; |
3495 | break; | |
3496 | } | |
3497 | } | |
3498 | ||
07428872 | 3499 | dgsi = gsi_after_labels (succbb); |
3500 | gsi = gsi_last_bb (bb); | |
3501 | for (gsi_prev (&gsi); !gsi_end_p (gsi); gsi_prev (&gsi)) | |
3502 | { | |
3503 | gimple stmt = gsi_stmt (gsi); | |
896a0c42 | 3504 | tree lhs; |
07428872 | 3505 | if (is_gimple_debug (stmt)) |
3506 | continue; | |
3507 | if (gimple_code (stmt) == GIMPLE_LABEL) | |
3508 | break; | |
896a0c42 | 3509 | lhs = gimple_assign_lhs (stmt); |
3510 | /* Unfortunately we don't have dominance info updated at this | |
3511 | point, so checking if | |
3512 | dominated_by_p (CDI_DOMINATORS, succbb, | |
3513 | gimple_bb (SSA_NAME_DEF_STMT (TREE_OPERAND (lhs, 0))) | |
3514 | would be too costly. Thus, avoid sinking any clobbers that | |
3515 | refer to non-(D) SSA_NAMEs. */ | |
3516 | if (TREE_CODE (lhs) == MEM_REF | |
3517 | && TREE_CODE (TREE_OPERAND (lhs, 0)) == SSA_NAME | |
3518 | && !SSA_NAME_IS_DEFAULT_DEF (TREE_OPERAND (lhs, 0))) | |
3519 | { | |
0ba38440 | 3520 | unlink_stmt_vdef (stmt); |
896a0c42 | 3521 | gsi_remove (&gsi, true); |
3522 | release_defs (stmt); | |
3523 | continue; | |
3524 | } | |
0ba38440 | 3525 | |
3526 | /* As we do not change stmt order when sinking across a | |
3527 | forwarder edge we can keep virtual operands in place. */ | |
07428872 | 3528 | gsi_remove (&gsi, false); |
0ba38440 | 3529 | gsi_insert_before (&dgsi, stmt, GSI_NEW_STMT); |
3530 | ||
3531 | /* But adjust virtual operands if we sunk across a PHI node. */ | |
3532 | if (vuse) | |
3533 | { | |
3534 | gimple use_stmt; | |
3535 | imm_use_iterator iter; | |
3536 | use_operand_p use_p; | |
3537 | FOR_EACH_IMM_USE_STMT (use_stmt, iter, vuse) | |
3538 | FOR_EACH_IMM_USE_ON_STMT (use_p, iter) | |
3539 | SET_USE (use_p, gimple_vdef (stmt)); | |
587a19f1 | 3540 | if (SSA_NAME_OCCURS_IN_ABNORMAL_PHI (vuse)) |
3541 | { | |
3542 | SSA_NAME_OCCURS_IN_ABNORMAL_PHI (gimple_vdef (stmt)) = 1; | |
3543 | SSA_NAME_OCCURS_IN_ABNORMAL_PHI (vuse) = 0; | |
3544 | } | |
0ba38440 | 3545 | /* Adjust the incoming virtual operand. */ |
3546 | SET_USE (PHI_ARG_DEF_PTR_FROM_EDGE (vphi, succe), gimple_vuse (stmt)); | |
3547 | SET_USE (gimple_vuse_op (stmt), vuse); | |
3548 | } | |
8aacb2c5 | 3549 | /* If there isn't a single predecessor but no virtual PHI node |
3550 | arrange for virtual operands to be renamed. */ | |
3551 | else if (gimple_vuse_op (stmt) != NULL_USE_OPERAND_P | |
3552 | && !single_pred_p (succbb)) | |
3553 | { | |
3554 | /* In this case there will be no use of the VDEF of this stmt. | |
3555 | ??? Unless this is a secondary opportunity and we have not | |
3556 | removed unreachable blocks yet, so we cannot assert this. | |
3557 | Which also means we will end up renaming too many times. */ | |
3558 | SET_USE (gimple_vuse_op (stmt), gimple_vop (cfun)); | |
3559 | mark_virtual_operands_for_renaming (cfun); | |
3560 | todo |= TODO_update_ssa_only_virtuals; | |
3561 | } | |
07428872 | 3562 | } |
3563 | ||
8aacb2c5 | 3564 | return todo; |
07428872 | 3565 | } |
3566 | ||
778f5bdd | 3567 | /* At the end of inlining, we can lower EH_DISPATCH. Return true when |
3568 | we have found some duplicate labels and removed some edges. */ | |
3bd82487 | 3569 | |
778f5bdd | 3570 | static bool |
1a91d914 | 3571 | lower_eh_dispatch (basic_block src, geh_dispatch *stmt) |
3bd82487 | 3572 | { |
e38def9c | 3573 | gimple_stmt_iterator gsi; |
3574 | int region_nr; | |
3575 | eh_region r; | |
3576 | tree filter, fn; | |
3577 | gimple x; | |
778f5bdd | 3578 | bool redirected = false; |
3bd82487 | 3579 | |
e38def9c | 3580 | region_nr = gimple_eh_dispatch_region (stmt); |
3581 | r = get_eh_region_from_number (region_nr); | |
3bd82487 | 3582 | |
e38def9c | 3583 | gsi = gsi_last_bb (src); |
3bd82487 | 3584 | |
e38def9c | 3585 | switch (r->type) |
3bd82487 | 3586 | { |
e38def9c | 3587 | case ERT_TRY: |
3588 | { | |
c2078b80 | 3589 | auto_vec<tree> labels; |
e38def9c | 3590 | tree default_label = NULL; |
3591 | eh_catch c; | |
3592 | edge_iterator ei; | |
3593 | edge e; | |
431205b7 | 3594 | hash_set<tree> seen_values; |
e38def9c | 3595 | |
3596 | /* Collect the labels for a switch. Zero the post_landing_pad | |
3597 | field becase we'll no longer have anything keeping these labels | |
9d75589a | 3598 | in existence and the optimizer will be free to merge these |
e38def9c | 3599 | blocks at will. */ |
3600 | for (c = r->u.eh_try.first_catch; c ; c = c->next_catch) | |
3601 | { | |
3602 | tree tp_node, flt_node, lab = c->label; | |
778f5bdd | 3603 | bool have_label = false; |
3bd82487 | 3604 | |
e38def9c | 3605 | c->label = NULL; |
3606 | tp_node = c->type_list; | |
3607 | flt_node = c->filter_list; | |
3608 | ||
3609 | if (tp_node == NULL) | |
3610 | { | |
3611 | default_label = lab; | |
3612 | break; | |
3613 | } | |
3614 | do | |
3615 | { | |
778f5bdd | 3616 | /* Filter out duplicate labels that arise when this handler |
3617 | is shadowed by an earlier one. When no labels are | |
3618 | attached to the handler anymore, we remove | |
3619 | the corresponding edge and then we delete unreachable | |
3620 | blocks at the end of this pass. */ | |
431205b7 | 3621 | if (! seen_values.contains (TREE_VALUE (flt_node))) |
778f5bdd | 3622 | { |
b6e3dd65 | 3623 | tree t = build_case_label (TREE_VALUE (flt_node), |
3624 | NULL, lab); | |
f1f41a6c | 3625 | labels.safe_push (t); |
431205b7 | 3626 | seen_values.add (TREE_VALUE (flt_node)); |
778f5bdd | 3627 | have_label = true; |
3628 | } | |
e38def9c | 3629 | |
3630 | tp_node = TREE_CHAIN (tp_node); | |
3631 | flt_node = TREE_CHAIN (flt_node); | |
3632 | } | |
3633 | while (tp_node); | |
778f5bdd | 3634 | if (! have_label) |
3635 | { | |
3636 | remove_edge (find_edge (src, label_to_block (lab))); | |
3637 | redirected = true; | |
3638 | } | |
e38def9c | 3639 | } |
3640 | ||
3641 | /* Clean up the edge flags. */ | |
3642 | FOR_EACH_EDGE (e, ei, src->succs) | |
3643 | { | |
3644 | if (e->flags & EDGE_FALLTHRU) | |
3645 | { | |
3646 | /* If there was no catch-all, use the fallthru edge. */ | |
3647 | if (default_label == NULL) | |
3648 | default_label = gimple_block_label (e->dest); | |
3649 | e->flags &= ~EDGE_FALLTHRU; | |
3650 | } | |
3651 | } | |
3652 | gcc_assert (default_label != NULL); | |
3653 | ||
3654 | /* Don't generate a switch if there's only a default case. | |
3655 | This is common in the form of try { A; } catch (...) { B; }. */ | |
f1f41a6c | 3656 | if (!labels.exists ()) |
e38def9c | 3657 | { |
3658 | e = single_succ_edge (src); | |
3659 | e->flags |= EDGE_FALLTHRU; | |
3660 | } | |
3661 | else | |
3662 | { | |
b9a16870 | 3663 | fn = builtin_decl_implicit (BUILT_IN_EH_FILTER); |
bad12c62 | 3664 | x = gimple_build_call (fn, 1, build_int_cst (integer_type_node, |
3665 | region_nr)); | |
f9e245b2 | 3666 | filter = create_tmp_var (TREE_TYPE (TREE_TYPE (fn))); |
e38def9c | 3667 | filter = make_ssa_name (filter, x); |
3668 | gimple_call_set_lhs (x, filter); | |
3669 | gsi_insert_before (&gsi, x, GSI_SAME_STMT); | |
3670 | ||
3671 | /* Turn the default label into a default case. */ | |
b6e3dd65 | 3672 | default_label = build_case_label (NULL, NULL, default_label); |
e38def9c | 3673 | sort_case_labels (labels); |
3674 | ||
49a70175 | 3675 | x = gimple_build_switch (filter, default_label, labels); |
e38def9c | 3676 | gsi_insert_before (&gsi, x, GSI_SAME_STMT); |
e38def9c | 3677 | } |
3678 | } | |
3679 | break; | |
3680 | ||
3681 | case ERT_ALLOWED_EXCEPTIONS: | |
3682 | { | |
3683 | edge b_e = BRANCH_EDGE (src); | |
3684 | edge f_e = FALLTHRU_EDGE (src); | |
3685 | ||
b9a16870 | 3686 | fn = builtin_decl_implicit (BUILT_IN_EH_FILTER); |
bad12c62 | 3687 | x = gimple_build_call (fn, 1, build_int_cst (integer_type_node, |
3688 | region_nr)); | |
f9e245b2 | 3689 | filter = create_tmp_var (TREE_TYPE (TREE_TYPE (fn))); |
e38def9c | 3690 | filter = make_ssa_name (filter, x); |
3691 | gimple_call_set_lhs (x, filter); | |
3692 | gsi_insert_before (&gsi, x, GSI_SAME_STMT); | |
3693 | ||
3694 | r->u.allowed.label = NULL; | |
3695 | x = gimple_build_cond (EQ_EXPR, filter, | |
3696 | build_int_cst (TREE_TYPE (filter), | |
3697 | r->u.allowed.filter), | |
3698 | NULL_TREE, NULL_TREE); | |
3699 | gsi_insert_before (&gsi, x, GSI_SAME_STMT); | |
3700 | ||
3701 | b_e->flags = b_e->flags | EDGE_TRUE_VALUE; | |
3702 | f_e->flags = (f_e->flags & ~EDGE_FALLTHRU) | EDGE_FALSE_VALUE; | |
3703 | } | |
3704 | break; | |
3705 | ||
3706 | default: | |
3707 | gcc_unreachable (); | |
3bd82487 | 3708 | } |
e38def9c | 3709 | |
3710 | /* Replace the EH_DISPATCH with the SWITCH or COND generated above. */ | |
3711 | gsi_remove (&gsi, true); | |
778f5bdd | 3712 | return redirected; |
3bd82487 | 3713 | } |
3714 | ||
65b0537f | 3715 | namespace { |
3716 | ||
3717 | const pass_data pass_data_lower_eh_dispatch = | |
3718 | { | |
3719 | GIMPLE_PASS, /* type */ | |
3720 | "ehdisp", /* name */ | |
3721 | OPTGROUP_NONE, /* optinfo_flags */ | |
65b0537f | 3722 | TV_TREE_EH, /* tv_id */ |
3723 | PROP_gimple_lcf, /* properties_required */ | |
3724 | 0, /* properties_provided */ | |
3725 | 0, /* properties_destroyed */ | |
3726 | 0, /* todo_flags_start */ | |
8b88439e | 3727 | 0, /* todo_flags_finish */ |
65b0537f | 3728 | }; |
3729 | ||
3730 | class pass_lower_eh_dispatch : public gimple_opt_pass | |
3731 | { | |
3732 | public: | |
3733 | pass_lower_eh_dispatch (gcc::context *ctxt) | |
3734 | : gimple_opt_pass (pass_data_lower_eh_dispatch, ctxt) | |
3735 | {} | |
3736 | ||
3737 | /* opt_pass methods: */ | |
3738 | virtual bool gate (function *fun) { return fun->eh->region_tree != NULL; } | |
3739 | virtual unsigned int execute (function *); | |
3740 | ||
3741 | }; // class pass_lower_eh_dispatch | |
3742 | ||
3743 | unsigned | |
3744 | pass_lower_eh_dispatch::execute (function *fun) | |
e38def9c | 3745 | { |
3746 | basic_block bb; | |
07428872 | 3747 | int flags = 0; |
778f5bdd | 3748 | bool redirected = false; |
3bd82487 | 3749 | |
e38def9c | 3750 | assign_filter_values (); |
3d1eacdb | 3751 | |
65b0537f | 3752 | FOR_EACH_BB_FN (bb, fun) |
e38def9c | 3753 | { |
3754 | gimple last = last_stmt (bb); | |
1227a337 | 3755 | if (last == NULL) |
3756 | continue; | |
3757 | if (gimple_code (last) == GIMPLE_EH_DISPATCH) | |
e38def9c | 3758 | { |
1a91d914 | 3759 | redirected |= lower_eh_dispatch (bb, |
3760 | as_a <geh_dispatch *> (last)); | |
07428872 | 3761 | flags |= TODO_update_ssa_only_virtuals; |
3762 | } | |
3763 | else if (gimple_code (last) == GIMPLE_RESX) | |
3764 | { | |
3765 | if (stmt_can_throw_external (last)) | |
3766 | optimize_clobbers (bb); | |
3767 | else | |
3768 | flags |= sink_clobbers (bb); | |
e38def9c | 3769 | } |
3770 | } | |
3771 | ||
778f5bdd | 3772 | if (redirected) |
3773 | delete_unreachable_blocks (); | |
07428872 | 3774 | return flags; |
e38def9c | 3775 | } |
3776 | ||
cbe8bda8 | 3777 | } // anon namespace |
3778 | ||
3779 | gimple_opt_pass * | |
3780 | make_pass_lower_eh_dispatch (gcc::context *ctxt) | |
3781 | { | |
3782 | return new pass_lower_eh_dispatch (ctxt); | |
3783 | } | |
e38def9c | 3784 | \f |
390f4a4b | 3785 | /* Walk statements, see what regions and, optionally, landing pads |
3786 | are really referenced. | |
3787 | ||
3788 | Returns in R_REACHABLEP an sbitmap with bits set for reachable regions, | |
3789 | and in LP_REACHABLE an sbitmap with bits set for reachable landing pads. | |
3790 | ||
3791 | Passing NULL for LP_REACHABLE is valid, in this case only reachable | |
3792 | regions are marked. | |
3793 | ||
3794 | The caller is responsible for freeing the returned sbitmaps. */ | |
e38def9c | 3795 | |
3796 | static void | |
390f4a4b | 3797 | mark_reachable_handlers (sbitmap *r_reachablep, sbitmap *lp_reachablep) |
e38def9c | 3798 | { |
3799 | sbitmap r_reachable, lp_reachable; | |
e38def9c | 3800 | basic_block bb; |
390f4a4b | 3801 | bool mark_landing_pads = (lp_reachablep != NULL); |
3802 | gcc_checking_assert (r_reachablep != NULL); | |
3bd82487 | 3803 | |
f1f41a6c | 3804 | r_reachable = sbitmap_alloc (cfun->eh->region_array->length ()); |
53c5d9d4 | 3805 | bitmap_clear (r_reachable); |
390f4a4b | 3806 | *r_reachablep = r_reachable; |
3807 | ||
3808 | if (mark_landing_pads) | |
3809 | { | |
3810 | lp_reachable = sbitmap_alloc (cfun->eh->lp_array->length ()); | |
3811 | bitmap_clear (lp_reachable); | |
3812 | *lp_reachablep = lp_reachable; | |
3813 | } | |
3814 | else | |
3815 | lp_reachable = NULL; | |
3bd82487 | 3816 | |
fc00614f | 3817 | FOR_EACH_BB_FN (bb, cfun) |
3bd82487 | 3818 | { |
d0ac3b8a | 3819 | gimple_stmt_iterator gsi; |
e38def9c | 3820 | |
3821 | for (gsi = gsi_start_bb (bb); !gsi_end_p (gsi); gsi_next (&gsi)) | |
3822 | { | |
3823 | gimple stmt = gsi_stmt (gsi); | |
e38def9c | 3824 | |
390f4a4b | 3825 | if (mark_landing_pads) |
e38def9c | 3826 | { |
390f4a4b | 3827 | int lp_nr = lookup_stmt_eh_lp (stmt); |
3828 | ||
3829 | /* Negative LP numbers are MUST_NOT_THROW regions which | |
3830 | are not considered BB enders. */ | |
3831 | if (lp_nr < 0) | |
3832 | bitmap_set_bit (r_reachable, -lp_nr); | |
3833 | ||
3834 | /* Positive LP numbers are real landing pads, and BB enders. */ | |
3835 | else if (lp_nr > 0) | |
3836 | { | |
3837 | gcc_assert (gsi_one_before_end_p (gsi)); | |
3838 | eh_region region = get_eh_region_from_lp_number (lp_nr); | |
3839 | bitmap_set_bit (r_reachable, region->index); | |
3840 | bitmap_set_bit (lp_reachable, lp_nr); | |
3841 | } | |
e38def9c | 3842 | } |
4e392ca1 | 3843 | |
3844 | /* Avoid removing regions referenced from RESX/EH_DISPATCH. */ | |
3845 | switch (gimple_code (stmt)) | |
3846 | { | |
3847 | case GIMPLE_RESX: | |
1a91d914 | 3848 | bitmap_set_bit (r_reachable, |
3849 | gimple_resx_region (as_a <gresx *> (stmt))); | |
4e392ca1 | 3850 | break; |
3851 | case GIMPLE_EH_DISPATCH: | |
1a91d914 | 3852 | bitmap_set_bit (r_reachable, |
3853 | gimple_eh_dispatch_region ( | |
3854 | as_a <geh_dispatch *> (stmt))); | |
4e392ca1 | 3855 | break; |
9eb0aee3 | 3856 | case GIMPLE_CALL: |
3857 | if (gimple_call_builtin_p (stmt, BUILT_IN_EH_COPY_VALUES)) | |
3858 | for (int i = 0; i < 2; ++i) | |
3859 | { | |
3860 | tree rt = gimple_call_arg (stmt, i); | |
3861 | HOST_WIDE_INT ri = tree_to_shwi (rt); | |
3862 | ||
3863 | gcc_assert (ri = (int)ri); | |
3864 | bitmap_set_bit (r_reachable, ri); | |
3865 | } | |
3866 | break; | |
4e392ca1 | 3867 | default: |
3868 | break; | |
3869 | } | |
e38def9c | 3870 | } |
3bd82487 | 3871 | } |
390f4a4b | 3872 | } |
3873 | ||
3874 | /* Remove unreachable handlers and unreachable landing pads. */ | |
3875 | ||
3876 | static void | |
3877 | remove_unreachable_handlers (void) | |
3878 | { | |
3879 | sbitmap r_reachable, lp_reachable; | |
3880 | eh_region region; | |
3881 | eh_landing_pad lp; | |
3882 | unsigned i; | |
3883 | ||
3884 | mark_reachable_handlers (&r_reachable, &lp_reachable); | |
e38def9c | 3885 | |
3886 | if (dump_file) | |
3bd82487 | 3887 | { |
e38def9c | 3888 | fprintf (dump_file, "Before removal of unreachable regions:\n"); |
3889 | dump_eh_tree (dump_file, cfun); | |
3890 | fprintf (dump_file, "Reachable regions: "); | |
53c5d9d4 | 3891 | dump_bitmap_file (dump_file, r_reachable); |
e38def9c | 3892 | fprintf (dump_file, "Reachable landing pads: "); |
53c5d9d4 | 3893 | dump_bitmap_file (dump_file, lp_reachable); |
3bd82487 | 3894 | } |
3895 | ||
390f4a4b | 3896 | if (dump_file) |
3897 | { | |
3898 | FOR_EACH_VEC_SAFE_ELT (cfun->eh->region_array, i, region) | |
3899 | if (region && !bitmap_bit_p (r_reachable, region->index)) | |
3900 | fprintf (dump_file, | |
3901 | "Removing unreachable region %d\n", | |
3902 | region->index); | |
3903 | } | |
3904 | ||
3905 | remove_unreachable_eh_regions (r_reachable); | |
3bd82487 | 3906 | |
390f4a4b | 3907 | FOR_EACH_VEC_SAFE_ELT (cfun->eh->lp_array, i, lp) |
3908 | if (lp && !bitmap_bit_p (lp_reachable, lp->index)) | |
e38def9c | 3909 | { |
3910 | if (dump_file) | |
390f4a4b | 3911 | fprintf (dump_file, |
3912 | "Removing unreachable landing pad %d\n", | |
3913 | lp->index); | |
e38def9c | 3914 | remove_eh_landing_pad (lp); |
3915 | } | |
48e1416a | 3916 | |
e38def9c | 3917 | if (dump_file) |
3bd82487 | 3918 | { |
e38def9c | 3919 | fprintf (dump_file, "\n\nAfter removal of unreachable regions:\n"); |
3920 | dump_eh_tree (dump_file, cfun); | |
3921 | fprintf (dump_file, "\n\n"); | |
3bd82487 | 3922 | } |
3923 | ||
e38def9c | 3924 | sbitmap_free (r_reachable); |
3925 | sbitmap_free (lp_reachable); | |
3926 | ||
3927 | #ifdef ENABLE_CHECKING | |
3928 | verify_eh_tree (cfun); | |
3929 | #endif | |
3930 | } | |
3931 | ||
b00b0dc4 | 3932 | /* Remove unreachable handlers if any landing pads have been removed after |
3933 | last ehcleanup pass (due to gimple_purge_dead_eh_edges). */ | |
3934 | ||
3935 | void | |
3936 | maybe_remove_unreachable_handlers (void) | |
3937 | { | |
3938 | eh_landing_pad lp; | |
390f4a4b | 3939 | unsigned i; |
b00b0dc4 | 3940 | |
3941 | if (cfun->eh == NULL) | |
3942 | return; | |
390f4a4b | 3943 | |
3944 | FOR_EACH_VEC_SAFE_ELT (cfun->eh->lp_array, i, lp) | |
b00b0dc4 | 3945 | if (lp && lp->post_landing_pad) |
3946 | { | |
3947 | if (label_to_block (lp->post_landing_pad) == NULL) | |
3948 | { | |
3949 | remove_unreachable_handlers (); | |
3950 | return; | |
3951 | } | |
3952 | } | |
3953 | } | |
3954 | ||
e38def9c | 3955 | /* Remove regions that do not have landing pads. This assumes |
3956 | that remove_unreachable_handlers has already been run, and | |
390f4a4b | 3957 | that we've just manipulated the landing pads since then. |
3958 | ||
3959 | Preserve regions with landing pads and regions that prevent | |
3960 | exceptions from propagating further, even if these regions | |
3961 | are not reachable. */ | |
e38def9c | 3962 | |
3963 | static void | |
3964 | remove_unreachable_handlers_no_lp (void) | |
3965 | { | |
390f4a4b | 3966 | eh_region region; |
4b393c71 | 3967 | sbitmap r_reachable; |
390f4a4b | 3968 | unsigned i; |
4b393c71 | 3969 | |
390f4a4b | 3970 | mark_reachable_handlers (&r_reachable, /*lp_reachablep=*/NULL); |
4b393c71 | 3971 | |
390f4a4b | 3972 | FOR_EACH_VEC_SAFE_ELT (cfun->eh->region_array, i, region) |
4b393c71 | 3973 | { |
390f4a4b | 3974 | if (! region) |
3975 | continue; | |
3976 | ||
3977 | if (region->landing_pads != NULL | |
3978 | || region->type == ERT_MUST_NOT_THROW) | |
3979 | bitmap_set_bit (r_reachable, region->index); | |
3980 | ||
3981 | if (dump_file | |
3982 | && !bitmap_bit_p (r_reachable, region->index)) | |
3983 | fprintf (dump_file, | |
3984 | "Removing unreachable region %d\n", | |
3985 | region->index); | |
4b393c71 | 3986 | } |
e38def9c | 3987 | |
390f4a4b | 3988 | remove_unreachable_eh_regions (r_reachable); |
4b393c71 | 3989 | |
3990 | sbitmap_free (r_reachable); | |
3bd82487 | 3991 | } |
3992 | ||
e38def9c | 3993 | /* Undo critical edge splitting on an EH landing pad. Earlier, we |
3994 | optimisticaly split all sorts of edges, including EH edges. The | |
3995 | optimization passes in between may not have needed them; if not, | |
3996 | we should undo the split. | |
3997 | ||
3998 | Recognize this case by having one EH edge incoming to the BB and | |
3999 | one normal edge outgoing; BB should be empty apart from the | |
4000 | post_landing_pad label. | |
4001 | ||
4002 | Note that this is slightly different from the empty handler case | |
4003 | handled by cleanup_empty_eh, in that the actual handler may yet | |
4004 | have actual code but the landing pad has been separated from the | |
4005 | handler. As such, cleanup_empty_eh relies on this transformation | |
4006 | having been done first. */ | |
4c5fcca6 | 4007 | |
4008 | static bool | |
e38def9c | 4009 | unsplit_eh (eh_landing_pad lp) |
4c5fcca6 | 4010 | { |
e38def9c | 4011 | basic_block bb = label_to_block (lp->post_landing_pad); |
4012 | gimple_stmt_iterator gsi; | |
4013 | edge e_in, e_out; | |
4014 | ||
4015 | /* Quickly check the edge counts on BB for singularity. */ | |
896a0c42 | 4016 | if (!single_pred_p (bb) || !single_succ_p (bb)) |
e38def9c | 4017 | return false; |
896a0c42 | 4018 | e_in = single_pred_edge (bb); |
4019 | e_out = single_succ_edge (bb); | |
4c5fcca6 | 4020 | |
e38def9c | 4021 | /* Input edge must be EH and output edge must be normal. */ |
4022 | if ((e_in->flags & EDGE_EH) == 0 || (e_out->flags & EDGE_EH) != 0) | |
4023 | return false; | |
4024 | ||
0b76e49c | 4025 | /* The block must be empty except for the labels and debug insns. */ |
4026 | gsi = gsi_after_labels (bb); | |
4027 | if (!gsi_end_p (gsi) && is_gimple_debug (gsi_stmt (gsi))) | |
4028 | gsi_next_nondebug (&gsi); | |
4029 | if (!gsi_end_p (gsi)) | |
e38def9c | 4030 | return false; |
4031 | ||
4032 | /* The destination block must not already have a landing pad | |
4033 | for a different region. */ | |
4034 | for (gsi = gsi_start_bb (e_out->dest); !gsi_end_p (gsi); gsi_next (&gsi)) | |
4c5fcca6 | 4035 | { |
1a91d914 | 4036 | glabel *label_stmt = dyn_cast <glabel *> (gsi_stmt (gsi)); |
e38def9c | 4037 | tree lab; |
4038 | int lp_nr; | |
4c5fcca6 | 4039 | |
1a91d914 | 4040 | if (!label_stmt) |
e38def9c | 4041 | break; |
1a91d914 | 4042 | lab = gimple_label_label (label_stmt); |
e38def9c | 4043 | lp_nr = EH_LANDING_PAD_NR (lab); |
4044 | if (lp_nr && get_eh_region_from_lp_number (lp_nr) != lp->region) | |
4045 | return false; | |
4046 | } | |
4c5fcca6 | 4047 | |
e9d5f86f | 4048 | /* The new destination block must not already be a destination of |
4049 | the source block, lest we merge fallthru and eh edges and get | |
4050 | all sorts of confused. */ | |
4051 | if (find_edge (e_in->src, e_out->dest)) | |
4052 | return false; | |
4053 | ||
c57e3b9d | 4054 | /* ??? We can get degenerate phis due to cfg cleanups. I would have |
4055 | thought this should have been cleaned up by a phicprop pass, but | |
4056 | that doesn't appear to handle virtuals. Propagate by hand. */ | |
4057 | if (!gimple_seq_empty_p (phi_nodes (bb))) | |
4058 | { | |
1a91d914 | 4059 | for (gphi_iterator gpi = gsi_start_phis (bb); !gsi_end_p (gpi); ) |
c57e3b9d | 4060 | { |
1a91d914 | 4061 | gimple use_stmt; |
4062 | gphi *phi = gpi.phi (); | |
c57e3b9d | 4063 | tree lhs = gimple_phi_result (phi); |
4064 | tree rhs = gimple_phi_arg_def (phi, 0); | |
4065 | use_operand_p use_p; | |
4066 | imm_use_iterator iter; | |
4067 | ||
4068 | FOR_EACH_IMM_USE_STMT (use_stmt, iter, lhs) | |
4069 | { | |
4070 | FOR_EACH_IMM_USE_ON_STMT (use_p, iter) | |
4071 | SET_USE (use_p, rhs); | |
4072 | } | |
4073 | ||
4074 | if (SSA_NAME_OCCURS_IN_ABNORMAL_PHI (lhs)) | |
4075 | SSA_NAME_OCCURS_IN_ABNORMAL_PHI (rhs) = 1; | |
4076 | ||
1a91d914 | 4077 | remove_phi_node (&gpi, true); |
c57e3b9d | 4078 | } |
4079 | } | |
3d1eacdb | 4080 | |
e38def9c | 4081 | if (dump_file && (dump_flags & TDF_DETAILS)) |
4082 | fprintf (dump_file, "Unsplit EH landing pad %d to block %i.\n", | |
4083 | lp->index, e_out->dest->index); | |
4084 | ||
4085 | /* Redirect the edge. Since redirect_eh_edge_1 expects to be moving | |
4086 | a successor edge, humor it. But do the real CFG change with the | |
4087 | predecessor of E_OUT in order to preserve the ordering of arguments | |
4088 | to the PHI nodes in E_OUT->DEST. */ | |
4089 | redirect_eh_edge_1 (e_in, e_out->dest, false); | |
4090 | redirect_edge_pred (e_out, e_in->src); | |
4091 | e_out->flags = e_in->flags; | |
4092 | e_out->probability = e_in->probability; | |
4093 | e_out->count = e_in->count; | |
4094 | remove_edge (e_in); | |
3d1eacdb | 4095 | |
e38def9c | 4096 | return true; |
4097 | } | |
3d1eacdb | 4098 | |
e38def9c | 4099 | /* Examine each landing pad block and see if it matches unsplit_eh. */ |
3d1eacdb | 4100 | |
e38def9c | 4101 | static bool |
4102 | unsplit_all_eh (void) | |
4103 | { | |
4104 | bool changed = false; | |
4105 | eh_landing_pad lp; | |
4106 | int i; | |
3d1eacdb | 4107 | |
f1f41a6c | 4108 | for (i = 1; vec_safe_iterate (cfun->eh->lp_array, i, &lp); ++i) |
e38def9c | 4109 | if (lp) |
4110 | changed |= unsplit_eh (lp); | |
4111 | ||
4112 | return changed; | |
4113 | } | |
4114 | ||
4115 | /* A subroutine of cleanup_empty_eh. Redirect all EH edges incoming | |
4116 | to OLD_BB to NEW_BB; return true on success, false on failure. | |
4117 | ||
4118 | OLD_BB_OUT is the edge into NEW_BB from OLD_BB, so if we miss any | |
4119 | PHI variables from OLD_BB we can pick them up from OLD_BB_OUT. | |
4120 | Virtual PHIs may be deleted and marked for renaming. */ | |
4121 | ||
4122 | static bool | |
4123 | cleanup_empty_eh_merge_phis (basic_block new_bb, basic_block old_bb, | |
c57e3b9d | 4124 | edge old_bb_out, bool change_region) |
e38def9c | 4125 | { |
1a91d914 | 4126 | gphi_iterator ngsi, ogsi; |
e38def9c | 4127 | edge_iterator ei; |
4128 | edge e; | |
e38def9c | 4129 | bitmap ophi_handled; |
4130 | ||
19bcc424 | 4131 | /* The destination block must not be a regular successor for any |
4132 | of the preds of the landing pad. Thus, avoid turning | |
4133 | <..> | |
4134 | | \ EH | |
4135 | | <..> | |
4136 | | / | |
4137 | <..> | |
4138 | into | |
4139 | <..> | |
4140 | | | EH | |
4141 | <..> | |
4142 | which CFG verification would choke on. See PR45172 and PR51089. */ | |
4143 | FOR_EACH_EDGE (e, ei, old_bb->preds) | |
4144 | if (find_edge (e->src, new_bb)) | |
4145 | return false; | |
4146 | ||
e38def9c | 4147 | FOR_EACH_EDGE (e, ei, old_bb->preds) |
4148 | redirect_edge_var_map_clear (e); | |
4149 | ||
4150 | ophi_handled = BITMAP_ALLOC (NULL); | |
e38def9c | 4151 | |
4152 | /* First, iterate through the PHIs on NEW_BB and set up the edge_var_map | |
4153 | for the edges we're going to move. */ | |
4154 | for (ngsi = gsi_start_phis (new_bb); !gsi_end_p (ngsi); gsi_next (&ngsi)) | |
4155 | { | |
1a91d914 | 4156 | gphi *ophi, *nphi = ngsi.phi (); |
e38def9c | 4157 | tree nresult, nop; |
4158 | ||
4159 | nresult = gimple_phi_result (nphi); | |
4160 | nop = gimple_phi_arg_def (nphi, old_bb_out->dest_idx); | |
4161 | ||
4162 | /* Find the corresponding PHI in OLD_BB so we can forward-propagate | |
4163 | the source ssa_name. */ | |
4164 | ophi = NULL; | |
4165 | for (ogsi = gsi_start_phis (old_bb); !gsi_end_p (ogsi); gsi_next (&ogsi)) | |
4166 | { | |
1a91d914 | 4167 | ophi = ogsi.phi (); |
e38def9c | 4168 | if (gimple_phi_result (ophi) == nop) |
4169 | break; | |
4170 | ophi = NULL; | |
927a6b6b | 4171 | } |
3d1eacdb | 4172 | |
e38def9c | 4173 | /* If we did find the corresponding PHI, copy those inputs. */ |
4174 | if (ophi) | |
4c5fcca6 | 4175 | { |
6e21b2e0 | 4176 | /* If NOP is used somewhere else beyond phis in new_bb, give up. */ |
4177 | if (!has_single_use (nop)) | |
4178 | { | |
4179 | imm_use_iterator imm_iter; | |
4180 | use_operand_p use_p; | |
4181 | ||
4182 | FOR_EACH_IMM_USE_FAST (use_p, imm_iter, nop) | |
4183 | { | |
4184 | if (!gimple_debug_bind_p (USE_STMT (use_p)) | |
4185 | && (gimple_code (USE_STMT (use_p)) != GIMPLE_PHI | |
4186 | || gimple_bb (USE_STMT (use_p)) != new_bb)) | |
4187 | goto fail; | |
4188 | } | |
4189 | } | |
e38def9c | 4190 | bitmap_set_bit (ophi_handled, SSA_NAME_VERSION (nop)); |
4191 | FOR_EACH_EDGE (e, ei, old_bb->preds) | |
3d1eacdb | 4192 | { |
e38def9c | 4193 | location_t oloc; |
4194 | tree oop; | |
4195 | ||
4196 | if ((e->flags & EDGE_EH) == 0) | |
4197 | continue; | |
4198 | oop = gimple_phi_arg_def (ophi, e->dest_idx); | |
4199 | oloc = gimple_phi_arg_location (ophi, e->dest_idx); | |
60d535d2 | 4200 | redirect_edge_var_map_add (e, nresult, oop, oloc); |
3d1eacdb | 4201 | } |
e38def9c | 4202 | } |
077b5b8a | 4203 | /* If we didn't find the PHI, if it's a real variable or a VOP, we know |
e38def9c | 4204 | from the fact that OLD_BB is tree_empty_eh_handler_p that the |
4205 | variable is unchanged from input to the block and we can simply | |
4206 | re-use the input to NEW_BB from the OLD_BB_OUT edge. */ | |
4207 | else | |
4208 | { | |
4209 | location_t nloc | |
4210 | = gimple_phi_arg_location (nphi, old_bb_out->dest_idx); | |
4211 | FOR_EACH_EDGE (e, ei, old_bb->preds) | |
60d535d2 | 4212 | redirect_edge_var_map_add (e, nresult, nop, nloc); |
e38def9c | 4213 | } |
4214 | } | |
4215 | ||
4216 | /* Second, verify that all PHIs from OLD_BB have been handled. If not, | |
4217 | we don't know what values from the other edges into NEW_BB to use. */ | |
4218 | for (ogsi = gsi_start_phis (old_bb); !gsi_end_p (ogsi); gsi_next (&ogsi)) | |
4219 | { | |
1a91d914 | 4220 | gphi *ophi = ogsi.phi (); |
e38def9c | 4221 | tree oresult = gimple_phi_result (ophi); |
4222 | if (!bitmap_bit_p (ophi_handled, SSA_NAME_VERSION (oresult))) | |
4223 | goto fail; | |
4224 | } | |
4225 | ||
e38def9c | 4226 | /* Finally, move the edges and update the PHIs. */ |
4227 | for (ei = ei_start (old_bb->preds); (e = ei_safe_edge (ei)); ) | |
4228 | if (e->flags & EDGE_EH) | |
4229 | { | |
3a37f7bd | 4230 | /* ??? CFG manipluation routines do not try to update loop |
4231 | form on edge redirection. Do so manually here for now. */ | |
4232 | /* If we redirect a loop entry or latch edge that will either create | |
4233 | a multiple entry loop or rotate the loop. If the loops merge | |
4234 | we may have created a loop with multiple latches. | |
4235 | All of this isn't easily fixed thus cancel the affected loop | |
4236 | and mark the other loop as possibly having multiple latches. */ | |
b3083327 | 4237 | if (e->dest == e->dest->loop_father->header) |
3a37f7bd | 4238 | { |
d25159cc | 4239 | mark_loop_for_removal (e->dest->loop_father); |
3a37f7bd | 4240 | new_bb->loop_father->latch = NULL; |
d25159cc | 4241 | loops_state_set (LOOPS_MAY_HAVE_MULTIPLE_LATCHES); |
3a37f7bd | 4242 | } |
c57e3b9d | 4243 | redirect_eh_edge_1 (e, new_bb, change_region); |
e38def9c | 4244 | redirect_edge_succ (e, new_bb); |
4245 | flush_pending_stmts (e); | |
4246 | } | |
4247 | else | |
4248 | ei_next (&ei); | |
3bd82487 | 4249 | |
e38def9c | 4250 | BITMAP_FREE (ophi_handled); |
e38def9c | 4251 | return true; |
4252 | ||
4253 | fail: | |
4254 | FOR_EACH_EDGE (e, ei, old_bb->preds) | |
4255 | redirect_edge_var_map_clear (e); | |
4256 | BITMAP_FREE (ophi_handled); | |
e38def9c | 4257 | return false; |
4258 | } | |
4259 | ||
4260 | /* A subroutine of cleanup_empty_eh. Move a landing pad LP from its | |
4261 | old region to NEW_REGION at BB. */ | |
4262 | ||
4263 | static void | |
4264 | cleanup_empty_eh_move_lp (basic_block bb, edge e_out, | |
4265 | eh_landing_pad lp, eh_region new_region) | |
4266 | { | |
4267 | gimple_stmt_iterator gsi; | |
4268 | eh_landing_pad *pp; | |
4269 | ||
4270 | for (pp = &lp->region->landing_pads; *pp != lp; pp = &(*pp)->next_lp) | |
4271 | continue; | |
4272 | *pp = lp->next_lp; | |
4273 | ||
4274 | lp->region = new_region; | |
4275 | lp->next_lp = new_region->landing_pads; | |
4276 | new_region->landing_pads = lp; | |
4277 | ||
4278 | /* Delete the RESX that was matched within the empty handler block. */ | |
4279 | gsi = gsi_last_bb (bb); | |
bc8a8451 | 4280 | unlink_stmt_vdef (gsi_stmt (gsi)); |
e38def9c | 4281 | gsi_remove (&gsi, true); |
4282 | ||
4283 | /* Clean up E_OUT for the fallthru. */ | |
4284 | e_out->flags = (e_out->flags & ~EDGE_EH) | EDGE_FALLTHRU; | |
4285 | e_out->probability = REG_BR_PROB_BASE; | |
4286 | } | |
4287 | ||
4288 | /* A subroutine of cleanup_empty_eh. Handle more complex cases of | |
48e1416a | 4289 | unsplitting than unsplit_eh was prepared to handle, e.g. when |
e38def9c | 4290 | multiple incoming edges and phis are involved. */ |
4291 | ||
4292 | static bool | |
c57e3b9d | 4293 | cleanup_empty_eh_unsplit (basic_block bb, edge e_out, eh_landing_pad lp) |
e38def9c | 4294 | { |
4295 | gimple_stmt_iterator gsi; | |
e38def9c | 4296 | tree lab; |
4297 | ||
4298 | /* We really ought not have totally lost everything following | |
4299 | a landing pad label. Given that BB is empty, there had better | |
4300 | be a successor. */ | |
4301 | gcc_assert (e_out != NULL); | |
4302 | ||
c57e3b9d | 4303 | /* The destination block must not already have a landing pad |
4304 | for a different region. */ | |
e38def9c | 4305 | lab = NULL; |
4306 | for (gsi = gsi_start_bb (e_out->dest); !gsi_end_p (gsi); gsi_next (&gsi)) | |
4307 | { | |
1a91d914 | 4308 | glabel *stmt = dyn_cast <glabel *> (gsi_stmt (gsi)); |
c57e3b9d | 4309 | int lp_nr; |
4310 | ||
1a91d914 | 4311 | if (!stmt) |
e38def9c | 4312 | break; |
4313 | lab = gimple_label_label (stmt); | |
c57e3b9d | 4314 | lp_nr = EH_LANDING_PAD_NR (lab); |
4315 | if (lp_nr && get_eh_region_from_lp_number (lp_nr) != lp->region) | |
4316 | return false; | |
e38def9c | 4317 | } |
e38def9c | 4318 | |
4319 | /* Attempt to move the PHIs into the successor block. */ | |
c57e3b9d | 4320 | if (cleanup_empty_eh_merge_phis (e_out->dest, bb, e_out, false)) |
e38def9c | 4321 | { |
4322 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
4323 | fprintf (dump_file, | |
c57e3b9d | 4324 | "Unsplit EH landing pad %d to block %i " |
4325 | "(via cleanup_empty_eh).\n", | |
4326 | lp->index, e_out->dest->index); | |
e38def9c | 4327 | return true; |
4328 | } | |
4329 | ||
4330 | return false; | |
4331 | } | |
4332 | ||
a9309f85 | 4333 | /* Return true if edge E_FIRST is part of an empty infinite loop |
4334 | or leads to such a loop through a series of single successor | |
4335 | empty bbs. */ | |
4336 | ||
4337 | static bool | |
4338 | infinite_empty_loop_p (edge e_first) | |
4339 | { | |
4340 | bool inf_loop = false; | |
4341 | edge e; | |
4342 | ||
4343 | if (e_first->dest == e_first->src) | |
4344 | return true; | |
4345 | ||
4346 | e_first->src->aux = (void *) 1; | |
4347 | for (e = e_first; single_succ_p (e->dest); e = single_succ_edge (e->dest)) | |
4348 | { | |
4349 | gimple_stmt_iterator gsi; | |
4350 | if (e->dest->aux) | |
4351 | { | |
4352 | inf_loop = true; | |
4353 | break; | |
4354 | } | |
4355 | e->dest->aux = (void *) 1; | |
4356 | gsi = gsi_after_labels (e->dest); | |
4357 | if (!gsi_end_p (gsi) && is_gimple_debug (gsi_stmt (gsi))) | |
4358 | gsi_next_nondebug (&gsi); | |
4359 | if (!gsi_end_p (gsi)) | |
4360 | break; | |
4361 | } | |
4362 | e_first->src->aux = NULL; | |
4363 | for (e = e_first; e->dest->aux; e = single_succ_edge (e->dest)) | |
4364 | e->dest->aux = NULL; | |
4365 | ||
4366 | return inf_loop; | |
4367 | } | |
4368 | ||
e38def9c | 4369 | /* Examine the block associated with LP to determine if it's an empty |
4370 | handler for its EH region. If so, attempt to redirect EH edges to | |
4371 | an outer region. Return true the CFG was updated in any way. This | |
4372 | is similar to jump forwarding, just across EH edges. */ | |
4373 | ||
4374 | static bool | |
4375 | cleanup_empty_eh (eh_landing_pad lp) | |
4376 | { | |
4377 | basic_block bb = label_to_block (lp->post_landing_pad); | |
4378 | gimple_stmt_iterator gsi; | |
4379 | gimple resx; | |
4380 | eh_region new_region; | |
4381 | edge_iterator ei; | |
4382 | edge e, e_out; | |
4383 | bool has_non_eh_pred; | |
b74338cf | 4384 | bool ret = false; |
e38def9c | 4385 | int new_lp_nr; |
4386 | ||
4387 | /* There can be zero or one edges out of BB. This is the quickest test. */ | |
4388 | switch (EDGE_COUNT (bb->succs)) | |
4389 | { | |
4390 | case 0: | |
4391 | e_out = NULL; | |
4392 | break; | |
4393 | case 1: | |
896a0c42 | 4394 | e_out = single_succ_edge (bb); |
e38def9c | 4395 | break; |
4396 | default: | |
4397 | return false; | |
4398 | } | |
b74338cf | 4399 | |
4400 | resx = last_stmt (bb); | |
4401 | if (resx && is_gimple_resx (resx)) | |
4402 | { | |
4403 | if (stmt_can_throw_external (resx)) | |
4404 | optimize_clobbers (bb); | |
4405 | else if (sink_clobbers (bb)) | |
4406 | ret = true; | |
4407 | } | |
4408 | ||
e38def9c | 4409 | gsi = gsi_after_labels (bb); |
4410 | ||
4411 | /* Make sure to skip debug statements. */ | |
4412 | if (!gsi_end_p (gsi) && is_gimple_debug (gsi_stmt (gsi))) | |
4413 | gsi_next_nondebug (&gsi); | |
4414 | ||
4415 | /* If the block is totally empty, look for more unsplitting cases. */ | |
4416 | if (gsi_end_p (gsi)) | |
e54fce5c | 4417 | { |
ae3a21c9 | 4418 | /* For the degenerate case of an infinite loop bail out. |
4419 | If bb has no successors and is totally empty, which can happen e.g. | |
4420 | because of incorrect noreturn attribute, bail out too. */ | |
4421 | if (e_out == NULL | |
4422 | || infinite_empty_loop_p (e_out)) | |
b74338cf | 4423 | return ret; |
e54fce5c | 4424 | |
b74338cf | 4425 | return ret | cleanup_empty_eh_unsplit (bb, e_out, lp); |
e54fce5c | 4426 | } |
e38def9c | 4427 | |
367113ea | 4428 | /* The block should consist only of a single RESX statement, modulo a |
4429 | preceding call to __builtin_stack_restore if there is no outgoing | |
4430 | edge, since the call can be eliminated in this case. */ | |
e38def9c | 4431 | resx = gsi_stmt (gsi); |
367113ea | 4432 | if (!e_out && gimple_call_builtin_p (resx, BUILT_IN_STACK_RESTORE)) |
4433 | { | |
4434 | gsi_next (&gsi); | |
4435 | resx = gsi_stmt (gsi); | |
4436 | } | |
e38def9c | 4437 | if (!is_gimple_resx (resx)) |
b74338cf | 4438 | return ret; |
e38def9c | 4439 | gcc_assert (gsi_one_before_end_p (gsi)); |
4440 | ||
4441 | /* Determine if there are non-EH edges, or resx edges into the handler. */ | |
4442 | has_non_eh_pred = false; | |
4443 | FOR_EACH_EDGE (e, ei, bb->preds) | |
4444 | if (!(e->flags & EDGE_EH)) | |
4445 | has_non_eh_pred = true; | |
4446 | ||
4447 | /* Find the handler that's outer of the empty handler by looking at | |
4448 | where the RESX instruction was vectored. */ | |
4449 | new_lp_nr = lookup_stmt_eh_lp (resx); | |
4450 | new_region = get_eh_region_from_lp_number (new_lp_nr); | |
4451 | ||
4452 | /* If there's no destination region within the current function, | |
4453 | redirection is trivial via removing the throwing statements from | |
4454 | the EH region, removing the EH edges, and allowing the block | |
4455 | to go unreachable. */ | |
4456 | if (new_region == NULL) | |
4457 | { | |
4458 | gcc_assert (e_out == NULL); | |
4459 | for (ei = ei_start (bb->preds); (e = ei_safe_edge (ei)); ) | |
4460 | if (e->flags & EDGE_EH) | |
4461 | { | |
4462 | gimple stmt = last_stmt (e->src); | |
4463 | remove_stmt_from_eh_lp (stmt); | |
4464 | remove_edge (e); | |
4465 | } | |
4466 | else | |
4467 | ei_next (&ei); | |
4468 | goto succeed; | |
4469 | } | |
4470 | ||
4471 | /* If the destination region is a MUST_NOT_THROW, allow the runtime | |
4472 | to handle the abort and allow the blocks to go unreachable. */ | |
4473 | if (new_region->type == ERT_MUST_NOT_THROW) | |
4474 | { | |
4475 | for (ei = ei_start (bb->preds); (e = ei_safe_edge (ei)); ) | |
4476 | if (e->flags & EDGE_EH) | |
4477 | { | |
4478 | gimple stmt = last_stmt (e->src); | |
4479 | remove_stmt_from_eh_lp (stmt); | |
4480 | add_stmt_to_eh_lp (stmt, new_lp_nr); | |
4481 | remove_edge (e); | |
4482 | } | |
4483 | else | |
4484 | ei_next (&ei); | |
4485 | goto succeed; | |
4486 | } | |
4487 | ||
4488 | /* Try to redirect the EH edges and merge the PHIs into the destination | |
4489 | landing pad block. If the merge succeeds, we'll already have redirected | |
4490 | all the EH edges. The handler itself will go unreachable if there were | |
4491 | no normal edges. */ | |
c57e3b9d | 4492 | if (cleanup_empty_eh_merge_phis (e_out->dest, bb, e_out, true)) |
e38def9c | 4493 | goto succeed; |
4494 | ||
4495 | /* Finally, if all input edges are EH edges, then we can (potentially) | |
4496 | reduce the number of transfers from the runtime by moving the landing | |
4497 | pad from the original region to the new region. This is a win when | |
4498 | we remove the last CLEANUP region along a particular exception | |
4499 | propagation path. Since nothing changes except for the region with | |
4500 | which the landing pad is associated, the PHI nodes do not need to be | |
4501 | adjusted at all. */ | |
4502 | if (!has_non_eh_pred) | |
4503 | { | |
4504 | cleanup_empty_eh_move_lp (bb, e_out, lp, new_region); | |
4505 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
4506 | fprintf (dump_file, "Empty EH handler %i moved to EH region %i.\n", | |
4507 | lp->index, new_region->index); | |
4508 | ||
4509 | /* ??? The CFG didn't change, but we may have rendered the | |
4510 | old EH region unreachable. Trigger a cleanup there. */ | |
4c5fcca6 | 4511 | return true; |
4512 | } | |
e38def9c | 4513 | |
b74338cf | 4514 | return ret; |
e38def9c | 4515 | |
4516 | succeed: | |
4517 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
4518 | fprintf (dump_file, "Empty EH handler %i removed.\n", lp->index); | |
4519 | remove_eh_landing_pad (lp); | |
4520 | return true; | |
4c5fcca6 | 4521 | } |
4522 | ||
e38def9c | 4523 | /* Do a post-order traversal of the EH region tree. Examine each |
4524 | post_landing_pad block and see if we can eliminate it as empty. */ | |
4525 | ||
4526 | static bool | |
4527 | cleanup_all_empty_eh (void) | |
4528 | { | |
4529 | bool changed = false; | |
4530 | eh_landing_pad lp; | |
4531 | int i; | |
4532 | ||
f1f41a6c | 4533 | for (i = 1; vec_safe_iterate (cfun->eh->lp_array, i, &lp); ++i) |
e38def9c | 4534 | if (lp) |
4535 | changed |= cleanup_empty_eh (lp); | |
4536 | ||
4537 | return changed; | |
4538 | } | |
4c5fcca6 | 4539 | |
4540 | /* Perform cleanups and lowering of exception handling | |
4541 | 1) cleanups regions with handlers doing nothing are optimized out | |
4542 | 2) MUST_NOT_THROW regions that became dead because of 1) are optimized out | |
4543 | 3) Info about regions that are containing instructions, and regions | |
4544 | reachable via local EH edges is collected | |
c31fb425 | 4545 | 4) Eh tree is pruned for regions no longer necessary. |
e38def9c | 4546 | |
4547 | TODO: Push MUST_NOT_THROW regions to the root of the EH tree. | |
4548 | Unify those that have the same failure decl and locus. | |
4549 | */ | |
4c5fcca6 | 4550 | |
4551 | static unsigned int | |
15100018 | 4552 | execute_cleanup_eh_1 (void) |
4c5fcca6 | 4553 | { |
e38def9c | 4554 | /* Do this first: unsplit_all_eh and cleanup_all_empty_eh can die |
4555 | looking up unreachable landing pads. */ | |
4556 | remove_unreachable_handlers (); | |
4c5fcca6 | 4557 | |
e38def9c | 4558 | /* Watch out for the region tree vanishing due to all unreachable. */ |
6b3688f5 | 4559 | if (cfun->eh->region_tree) |
4c5fcca6 | 4560 | { |
e38def9c | 4561 | bool changed = false; |
4c5fcca6 | 4562 | |
6b3688f5 | 4563 | if (optimize) |
4564 | changed |= unsplit_all_eh (); | |
e38def9c | 4565 | changed |= cleanup_all_empty_eh (); |
4566 | ||
4567 | if (changed) | |
48d5ef93 | 4568 | { |
4569 | free_dominance_info (CDI_DOMINATORS); | |
4570 | free_dominance_info (CDI_POST_DOMINATORS); | |
4c5fcca6 | 4571 | |
e38def9c | 4572 | /* We delayed all basic block deletion, as we may have performed |
4573 | cleanups on EH edges while non-EH edges were still present. */ | |
4574 | delete_unreachable_blocks (); | |
4c5fcca6 | 4575 | |
e38def9c | 4576 | /* We manipulated the landing pads. Remove any region that no |
4577 | longer has a landing pad. */ | |
4578 | remove_unreachable_handlers_no_lp (); | |
4579 | ||
4580 | return TODO_cleanup_cfg | TODO_update_ssa_only_virtuals; | |
4581 | } | |
4c5fcca6 | 4582 | } |
4583 | ||
e38def9c | 4584 | return 0; |
4585 | } | |
4586 | ||
cbe8bda8 | 4587 | namespace { |
4588 | ||
4589 | const pass_data pass_data_cleanup_eh = | |
4590 | { | |
4591 | GIMPLE_PASS, /* type */ | |
4592 | "ehcleanup", /* name */ | |
4593 | OPTGROUP_NONE, /* optinfo_flags */ | |
cbe8bda8 | 4594 | TV_TREE_EH, /* tv_id */ |
4595 | PROP_gimple_lcf, /* properties_required */ | |
4596 | 0, /* properties_provided */ | |
4597 | 0, /* properties_destroyed */ | |
4598 | 0, /* todo_flags_start */ | |
8b88439e | 4599 | 0, /* todo_flags_finish */ |
4c5fcca6 | 4600 | }; |
cbe8bda8 | 4601 | |
4602 | class pass_cleanup_eh : public gimple_opt_pass | |
4603 | { | |
4604 | public: | |
9af5ce0c | 4605 | pass_cleanup_eh (gcc::context *ctxt) |
4606 | : gimple_opt_pass (pass_data_cleanup_eh, ctxt) | |
cbe8bda8 | 4607 | {} |
4608 | ||
4609 | /* opt_pass methods: */ | |
ae84f584 | 4610 | opt_pass * clone () { return new pass_cleanup_eh (m_ctxt); } |
31315c24 | 4611 | virtual bool gate (function *fun) |
4612 | { | |
4613 | return fun->eh != NULL && fun->eh->region_tree != NULL; | |
4614 | } | |
4615 | ||
65b0537f | 4616 | virtual unsigned int execute (function *); |
cbe8bda8 | 4617 | |
4618 | }; // class pass_cleanup_eh | |
4619 | ||
65b0537f | 4620 | unsigned int |
4621 | pass_cleanup_eh::execute (function *fun) | |
4622 | { | |
4623 | int ret = execute_cleanup_eh_1 (); | |
4624 | ||
4625 | /* If the function no longer needs an EH personality routine | |
4626 | clear it. This exposes cross-language inlining opportunities | |
4627 | and avoids references to a never defined personality routine. */ | |
4628 | if (DECL_FUNCTION_PERSONALITY (current_function_decl) | |
4629 | && function_needs_eh_personality (fun) != eh_personality_lang) | |
4630 | DECL_FUNCTION_PERSONALITY (current_function_decl) = NULL_TREE; | |
4631 | ||
4632 | return ret; | |
4633 | } | |
4634 | ||
cbe8bda8 | 4635 | } // anon namespace |
4636 | ||
4637 | gimple_opt_pass * | |
4638 | make_pass_cleanup_eh (gcc::context *ctxt) | |
4639 | { | |
4640 | return new pass_cleanup_eh (ctxt); | |
4641 | } | |
e38def9c | 4642 | \f |
4643 | /* Verify that BB containing STMT as the last statement, has precisely the | |
4644 | edge that make_eh_edges would create. */ | |
4645 | ||
4b987fac | 4646 | DEBUG_FUNCTION bool |
e38def9c | 4647 | verify_eh_edges (gimple stmt) |
4648 | { | |
4649 | basic_block bb = gimple_bb (stmt); | |
4650 | eh_landing_pad lp = NULL; | |
4651 | int lp_nr; | |
4652 | edge_iterator ei; | |
4653 | edge e, eh_edge; | |
4654 | ||
4655 | lp_nr = lookup_stmt_eh_lp (stmt); | |
4656 | if (lp_nr > 0) | |
4657 | lp = get_eh_landing_pad_from_number (lp_nr); | |
4658 | ||
4659 | eh_edge = NULL; | |
4660 | FOR_EACH_EDGE (e, ei, bb->succs) | |
4661 | { | |
4662 | if (e->flags & EDGE_EH) | |
4663 | { | |
4664 | if (eh_edge) | |
4665 | { | |
4666 | error ("BB %i has multiple EH edges", bb->index); | |
4667 | return true; | |
4668 | } | |
4669 | else | |
4670 | eh_edge = e; | |
4671 | } | |
4672 | } | |
4673 | ||
4674 | if (lp == NULL) | |
4675 | { | |
4676 | if (eh_edge) | |
4677 | { | |
4678 | error ("BB %i can not throw but has an EH edge", bb->index); | |
4679 | return true; | |
4680 | } | |
4681 | return false; | |
4682 | } | |
4683 | ||
4684 | if (!stmt_could_throw_p (stmt)) | |
4685 | { | |
4686 | error ("BB %i last statement has incorrectly set lp", bb->index); | |
4687 | return true; | |
4688 | } | |
4689 | ||
4690 | if (eh_edge == NULL) | |
4691 | { | |
4692 | error ("BB %i is missing an EH edge", bb->index); | |
4693 | return true; | |
4694 | } | |
4695 | ||
4696 | if (eh_edge->dest != label_to_block (lp->post_landing_pad)) | |
4697 | { | |
4698 | error ("Incorrect EH edge %i->%i", bb->index, eh_edge->dest->index); | |
4699 | return true; | |
4700 | } | |
4701 | ||
4702 | return false; | |
4703 | } | |
4704 | ||
4705 | /* Similarly, but handle GIMPLE_EH_DISPATCH specifically. */ | |
4706 | ||
4b987fac | 4707 | DEBUG_FUNCTION bool |
1a91d914 | 4708 | verify_eh_dispatch_edge (geh_dispatch *stmt) |
e38def9c | 4709 | { |
4710 | eh_region r; | |
4711 | eh_catch c; | |
4712 | basic_block src, dst; | |
4713 | bool want_fallthru = true; | |
4714 | edge_iterator ei; | |
4715 | edge e, fall_edge; | |
4716 | ||
4717 | r = get_eh_region_from_number (gimple_eh_dispatch_region (stmt)); | |
4718 | src = gimple_bb (stmt); | |
4719 | ||
4720 | FOR_EACH_EDGE (e, ei, src->succs) | |
4721 | gcc_assert (e->aux == NULL); | |
4722 | ||
4723 | switch (r->type) | |
4724 | { | |
4725 | case ERT_TRY: | |
4726 | for (c = r->u.eh_try.first_catch; c ; c = c->next_catch) | |
4727 | { | |
4728 | dst = label_to_block (c->label); | |
4729 | e = find_edge (src, dst); | |
4730 | if (e == NULL) | |
4731 | { | |
4732 | error ("BB %i is missing an edge", src->index); | |
4733 | return true; | |
4734 | } | |
4735 | e->aux = (void *)e; | |
4736 | ||
4737 | /* A catch-all handler doesn't have a fallthru. */ | |
4738 | if (c->type_list == NULL) | |
4739 | { | |
4740 | want_fallthru = false; | |
4741 | break; | |
4742 | } | |
4743 | } | |
4744 | break; | |
4745 | ||
4746 | case ERT_ALLOWED_EXCEPTIONS: | |
4747 | dst = label_to_block (r->u.allowed.label); | |
4748 | e = find_edge (src, dst); | |
4749 | if (e == NULL) | |
4750 | { | |
4751 | error ("BB %i is missing an edge", src->index); | |
4752 | return true; | |
4753 | } | |
4754 | e->aux = (void *)e; | |
4755 | break; | |
4756 | ||
4757 | default: | |
4758 | gcc_unreachable (); | |
4759 | } | |
4760 | ||
4761 | fall_edge = NULL; | |
4762 | FOR_EACH_EDGE (e, ei, src->succs) | |
4763 | { | |
4764 | if (e->flags & EDGE_FALLTHRU) | |
4765 | { | |
4766 | if (fall_edge != NULL) | |
4767 | { | |
4768 | error ("BB %i too many fallthru edges", src->index); | |
4769 | return true; | |
4770 | } | |
4771 | fall_edge = e; | |
4772 | } | |
4773 | else if (e->aux) | |
4774 | e->aux = NULL; | |
4775 | else | |
4776 | { | |
4777 | error ("BB %i has incorrect edge", src->index); | |
4778 | return true; | |
4779 | } | |
4780 | } | |
4781 | if ((fall_edge != NULL) ^ want_fallthru) | |
4782 | { | |
4783 | error ("BB %i has incorrect fallthru edge", src->index); | |
4784 | return true; | |
4785 | } | |
4786 | ||
4787 | return false; | |
4788 | } |