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6de9cd9a | 1 | /* Control flow functions for trees. |
56e84019 RH |
2 | Copyright (C) 2001, 2002, 2003, 2004, 2005, 2006 |
3 | Free Software Foundation, Inc. | |
6de9cd9a DN |
4 | Contributed by Diego Novillo <dnovillo@redhat.com> |
5 | ||
6 | This file is part of GCC. | |
7 | ||
8 | GCC is free software; you can redistribute it and/or modify | |
9 | it under the terms of the GNU General Public License as published by | |
10 | the Free Software Foundation; either version 2, or (at your option) | |
11 | any later version. | |
12 | ||
13 | GCC is distributed in the hope that it will be useful, | |
14 | but WITHOUT ANY WARRANTY; without even the implied warranty of | |
15 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
16 | GNU General Public License for more details. | |
17 | ||
18 | You should have received a copy of the GNU General Public License | |
19 | along with GCC; see the file COPYING. If not, write to | |
366ccddb KC |
20 | the Free Software Foundation, 51 Franklin Street, Fifth Floor, |
21 | Boston, MA 02110-1301, USA. */ | |
6de9cd9a DN |
22 | |
23 | #include "config.h" | |
24 | #include "system.h" | |
25 | #include "coretypes.h" | |
26 | #include "tm.h" | |
27 | #include "tree.h" | |
28 | #include "rtl.h" | |
29 | #include "tm_p.h" | |
30 | #include "hard-reg-set.h" | |
31 | #include "basic-block.h" | |
32 | #include "output.h" | |
6de9cd9a DN |
33 | #include "flags.h" |
34 | #include "function.h" | |
35 | #include "expr.h" | |
36 | #include "ggc.h" | |
37 | #include "langhooks.h" | |
38 | #include "diagnostic.h" | |
39 | #include "tree-flow.h" | |
40 | #include "timevar.h" | |
41 | #include "tree-dump.h" | |
42 | #include "tree-pass.h" | |
43 | #include "toplev.h" | |
44 | #include "except.h" | |
45 | #include "cfgloop.h" | |
42759f1e | 46 | #include "cfglayout.h" |
92b6dff3 | 47 | #include "hashtab.h" |
9af0df6b | 48 | #include "tree-ssa-propagate.h" |
6de9cd9a DN |
49 | |
50 | /* This file contains functions for building the Control Flow Graph (CFG) | |
51 | for a function tree. */ | |
52 | ||
53 | /* Local declarations. */ | |
54 | ||
55 | /* Initial capacity for the basic block array. */ | |
56 | static const int initial_cfg_capacity = 20; | |
57 | ||
d6be0d7f JL |
58 | /* This hash table allows us to efficiently lookup all CASE_LABEL_EXPRs |
59 | which use a particular edge. The CASE_LABEL_EXPRs are chained together | |
60 | via their TREE_CHAIN field, which we clear after we're done with the | |
61 | hash table to prevent problems with duplication of SWITCH_EXPRs. | |
92b6dff3 | 62 | |
d6be0d7f JL |
63 | Access to this list of CASE_LABEL_EXPRs allows us to efficiently |
64 | update the case vector in response to edge redirections. | |
92b6dff3 | 65 | |
d6be0d7f JL |
66 | Right now this table is set up and torn down at key points in the |
67 | compilation process. It would be nice if we could make the table | |
68 | more persistent. The key is getting notification of changes to | |
69 | the CFG (particularly edge removal, creation and redirection). */ | |
70 | ||
71 | struct edge_to_cases_elt | |
92b6dff3 JL |
72 | { |
73 | /* The edge itself. Necessary for hashing and equality tests. */ | |
74 | edge e; | |
75 | ||
d6be0d7f JL |
76 | /* The case labels associated with this edge. We link these up via |
77 | their TREE_CHAIN field, then we wipe out the TREE_CHAIN fields | |
78 | when we destroy the hash table. This prevents problems when copying | |
79 | SWITCH_EXPRs. */ | |
80 | tree case_labels; | |
92b6dff3 JL |
81 | }; |
82 | ||
d6be0d7f | 83 | static htab_t edge_to_cases; |
92b6dff3 | 84 | |
6de9cd9a DN |
85 | /* CFG statistics. */ |
86 | struct cfg_stats_d | |
87 | { | |
88 | long num_merged_labels; | |
89 | }; | |
90 | ||
91 | static struct cfg_stats_d cfg_stats; | |
92 | ||
93 | /* Nonzero if we found a computed goto while building basic blocks. */ | |
94 | static bool found_computed_goto; | |
95 | ||
96 | /* Basic blocks and flowgraphs. */ | |
97 | static basic_block create_bb (void *, void *, basic_block); | |
6de9cd9a DN |
98 | static void make_blocks (tree); |
99 | static void factor_computed_gotos (void); | |
6de9cd9a DN |
100 | |
101 | /* Edges. */ | |
102 | static void make_edges (void); | |
6de9cd9a DN |
103 | static void make_cond_expr_edges (basic_block); |
104 | static void make_switch_expr_edges (basic_block); | |
105 | static void make_goto_expr_edges (basic_block); | |
106 | static edge tree_redirect_edge_and_branch (edge, basic_block); | |
107 | static edge tree_try_redirect_by_replacing_jump (edge, basic_block); | |
c2924966 | 108 | static unsigned int split_critical_edges (void); |
6de9cd9a DN |
109 | |
110 | /* Various helpers. */ | |
111 | static inline bool stmt_starts_bb_p (tree, tree); | |
112 | static int tree_verify_flow_info (void); | |
113 | static void tree_make_forwarder_block (edge); | |
6de9cd9a | 114 | static void tree_cfg2vcg (FILE *); |
0a4fe58f | 115 | static inline void change_bb_for_stmt (tree t, basic_block bb); |
6de9cd9a DN |
116 | |
117 | /* Flowgraph optimization and cleanup. */ | |
118 | static void tree_merge_blocks (basic_block, basic_block); | |
119 | static bool tree_can_merge_blocks_p (basic_block, basic_block); | |
120 | static void remove_bb (basic_block); | |
be477406 | 121 | static edge find_taken_edge_computed_goto (basic_block, tree); |
6de9cd9a DN |
122 | static edge find_taken_edge_cond_expr (basic_block, tree); |
123 | static edge find_taken_edge_switch_expr (basic_block, tree); | |
124 | static tree find_case_label_for_value (tree, tree); | |
6de9cd9a | 125 | |
a930a4ef JH |
126 | void |
127 | init_empty_tree_cfg (void) | |
128 | { | |
129 | /* Initialize the basic block array. */ | |
130 | init_flow (); | |
131 | profile_status = PROFILE_ABSENT; | |
24bd1a0b DB |
132 | n_basic_blocks = NUM_FIXED_BLOCKS; |
133 | last_basic_block = NUM_FIXED_BLOCKS; | |
68f9b844 KH |
134 | basic_block_info = VEC_alloc (basic_block, gc, initial_cfg_capacity); |
135 | VEC_safe_grow (basic_block, gc, basic_block_info, initial_cfg_capacity); | |
136 | memset (VEC_address (basic_block, basic_block_info), 0, | |
137 | sizeof (basic_block) * initial_cfg_capacity); | |
a930a4ef JH |
138 | |
139 | /* Build a mapping of labels to their associated blocks. */ | |
e597f337 KH |
140 | label_to_block_map = VEC_alloc (basic_block, gc, initial_cfg_capacity); |
141 | VEC_safe_grow (basic_block, gc, label_to_block_map, initial_cfg_capacity); | |
142 | memset (VEC_address (basic_block, label_to_block_map), | |
143 | 0, sizeof (basic_block) * initial_cfg_capacity); | |
a930a4ef | 144 | |
68f9b844 KH |
145 | SET_BASIC_BLOCK (ENTRY_BLOCK, ENTRY_BLOCK_PTR); |
146 | SET_BASIC_BLOCK (EXIT_BLOCK, EXIT_BLOCK_PTR); | |
a930a4ef JH |
147 | ENTRY_BLOCK_PTR->next_bb = EXIT_BLOCK_PTR; |
148 | EXIT_BLOCK_PTR->prev_bb = ENTRY_BLOCK_PTR; | |
a930a4ef | 149 | } |
6de9cd9a DN |
150 | |
151 | /*--------------------------------------------------------------------------- | |
152 | Create basic blocks | |
153 | ---------------------------------------------------------------------------*/ | |
154 | ||
155 | /* Entry point to the CFG builder for trees. TP points to the list of | |
156 | statements to be added to the flowgraph. */ | |
157 | ||
158 | static void | |
159 | build_tree_cfg (tree *tp) | |
160 | { | |
161 | /* Register specific tree functions. */ | |
162 | tree_register_cfg_hooks (); | |
163 | ||
6de9cd9a DN |
164 | memset ((void *) &cfg_stats, 0, sizeof (cfg_stats)); |
165 | ||
a930a4ef | 166 | init_empty_tree_cfg (); |
6de9cd9a DN |
167 | |
168 | found_computed_goto = 0; | |
169 | make_blocks (*tp); | |
170 | ||
171 | /* Computed gotos are hell to deal with, especially if there are | |
172 | lots of them with a large number of destinations. So we factor | |
173 | them to a common computed goto location before we build the | |
174 | edge list. After we convert back to normal form, we will un-factor | |
175 | the computed gotos since factoring introduces an unwanted jump. */ | |
176 | if (found_computed_goto) | |
177 | factor_computed_gotos (); | |
178 | ||
f0b698c1 | 179 | /* Make sure there is always at least one block, even if it's empty. */ |
24bd1a0b | 180 | if (n_basic_blocks == NUM_FIXED_BLOCKS) |
6de9cd9a DN |
181 | create_empty_bb (ENTRY_BLOCK_PTR); |
182 | ||
6de9cd9a | 183 | /* Adjust the size of the array. */ |
68f9b844 KH |
184 | if (VEC_length (basic_block, basic_block_info) < (size_t) n_basic_blocks) |
185 | { | |
186 | size_t old_size = VEC_length (basic_block, basic_block_info); | |
187 | basic_block *p; | |
188 | VEC_safe_grow (basic_block, gc, basic_block_info, n_basic_blocks); | |
189 | p = VEC_address (basic_block, basic_block_info); | |
190 | memset (&p[old_size], 0, | |
191 | sizeof (basic_block) * (n_basic_blocks - old_size)); | |
192 | } | |
6de9cd9a | 193 | |
f667741c SB |
194 | /* To speed up statement iterator walks, we first purge dead labels. */ |
195 | cleanup_dead_labels (); | |
196 | ||
197 | /* Group case nodes to reduce the number of edges. | |
198 | We do this after cleaning up dead labels because otherwise we miss | |
199 | a lot of obvious case merging opportunities. */ | |
200 | group_case_labels (); | |
201 | ||
6de9cd9a DN |
202 | /* Create the edges of the flowgraph. */ |
203 | make_edges (); | |
204 | ||
205 | /* Debugging dumps. */ | |
206 | ||
207 | /* Write the flowgraph to a VCG file. */ | |
208 | { | |
209 | int local_dump_flags; | |
10d22567 ZD |
210 | FILE *vcg_file = dump_begin (TDI_vcg, &local_dump_flags); |
211 | if (vcg_file) | |
6de9cd9a | 212 | { |
10d22567 ZD |
213 | tree_cfg2vcg (vcg_file); |
214 | dump_end (TDI_vcg, vcg_file); | |
6de9cd9a DN |
215 | } |
216 | } | |
217 | ||
81cfbbc2 JH |
218 | #ifdef ENABLE_CHECKING |
219 | verify_stmts (); | |
220 | #endif | |
221 | ||
6de9cd9a DN |
222 | /* Dump a textual representation of the flowgraph. */ |
223 | if (dump_file) | |
224 | dump_tree_cfg (dump_file, dump_flags); | |
225 | } | |
226 | ||
c2924966 | 227 | static unsigned int |
6de9cd9a DN |
228 | execute_build_cfg (void) |
229 | { | |
230 | build_tree_cfg (&DECL_SAVED_TREE (current_function_decl)); | |
c2924966 | 231 | return 0; |
6de9cd9a DN |
232 | } |
233 | ||
234 | struct tree_opt_pass pass_build_cfg = | |
235 | { | |
236 | "cfg", /* name */ | |
237 | NULL, /* gate */ | |
238 | execute_build_cfg, /* execute */ | |
239 | NULL, /* sub */ | |
240 | NULL, /* next */ | |
241 | 0, /* static_pass_number */ | |
242 | TV_TREE_CFG, /* tv_id */ | |
243 | PROP_gimple_leh, /* properties_required */ | |
244 | PROP_cfg, /* properties_provided */ | |
245 | 0, /* properties_destroyed */ | |
246 | 0, /* todo_flags_start */ | |
9f8628ba PB |
247 | TODO_verify_stmts, /* todo_flags_finish */ |
248 | 0 /* letter */ | |
6de9cd9a DN |
249 | }; |
250 | ||
6531d1be | 251 | /* Search the CFG for any computed gotos. If found, factor them to a |
6de9cd9a | 252 | common computed goto site. Also record the location of that site so |
6531d1be | 253 | that we can un-factor the gotos after we have converted back to |
6de9cd9a DN |
254 | normal form. */ |
255 | ||
256 | static void | |
257 | factor_computed_gotos (void) | |
258 | { | |
259 | basic_block bb; | |
260 | tree factored_label_decl = NULL; | |
261 | tree var = NULL; | |
262 | tree factored_computed_goto_label = NULL; | |
263 | tree factored_computed_goto = NULL; | |
264 | ||
265 | /* We know there are one or more computed gotos in this function. | |
266 | Examine the last statement in each basic block to see if the block | |
267 | ends with a computed goto. */ | |
6531d1be | 268 | |
6de9cd9a DN |
269 | FOR_EACH_BB (bb) |
270 | { | |
271 | block_stmt_iterator bsi = bsi_last (bb); | |
272 | tree last; | |
273 | ||
274 | if (bsi_end_p (bsi)) | |
275 | continue; | |
276 | last = bsi_stmt (bsi); | |
277 | ||
278 | /* Ignore the computed goto we create when we factor the original | |
279 | computed gotos. */ | |
280 | if (last == factored_computed_goto) | |
281 | continue; | |
282 | ||
283 | /* If the last statement is a computed goto, factor it. */ | |
284 | if (computed_goto_p (last)) | |
285 | { | |
286 | tree assignment; | |
287 | ||
288 | /* The first time we find a computed goto we need to create | |
289 | the factored goto block and the variable each original | |
290 | computed goto will use for their goto destination. */ | |
291 | if (! factored_computed_goto) | |
292 | { | |
293 | basic_block new_bb = create_empty_bb (bb); | |
294 | block_stmt_iterator new_bsi = bsi_start (new_bb); | |
295 | ||
296 | /* Create the destination of the factored goto. Each original | |
297 | computed goto will put its desired destination into this | |
298 | variable and jump to the label we create immediately | |
299 | below. */ | |
300 | var = create_tmp_var (ptr_type_node, "gotovar"); | |
301 | ||
302 | /* Build a label for the new block which will contain the | |
303 | factored computed goto. */ | |
304 | factored_label_decl = create_artificial_label (); | |
305 | factored_computed_goto_label | |
306 | = build1 (LABEL_EXPR, void_type_node, factored_label_decl); | |
307 | bsi_insert_after (&new_bsi, factored_computed_goto_label, | |
308 | BSI_NEW_STMT); | |
309 | ||
310 | /* Build our new computed goto. */ | |
311 | factored_computed_goto = build1 (GOTO_EXPR, void_type_node, var); | |
312 | bsi_insert_after (&new_bsi, factored_computed_goto, | |
313 | BSI_NEW_STMT); | |
314 | } | |
315 | ||
316 | /* Copy the original computed goto's destination into VAR. */ | |
07beea0d AH |
317 | assignment = build2_gimple (GIMPLE_MODIFY_STMT, |
318 | var, GOTO_DESTINATION (last)); | |
6de9cd9a DN |
319 | bsi_insert_before (&bsi, assignment, BSI_SAME_STMT); |
320 | ||
321 | /* And re-vector the computed goto to the new destination. */ | |
322 | GOTO_DESTINATION (last) = factored_label_decl; | |
323 | } | |
324 | } | |
325 | } | |
326 | ||
327 | ||
6de9cd9a DN |
328 | /* Build a flowgraph for the statement_list STMT_LIST. */ |
329 | ||
330 | static void | |
331 | make_blocks (tree stmt_list) | |
332 | { | |
333 | tree_stmt_iterator i = tsi_start (stmt_list); | |
334 | tree stmt = NULL; | |
335 | bool start_new_block = true; | |
336 | bool first_stmt_of_list = true; | |
337 | basic_block bb = ENTRY_BLOCK_PTR; | |
338 | ||
339 | while (!tsi_end_p (i)) | |
340 | { | |
341 | tree prev_stmt; | |
342 | ||
343 | prev_stmt = stmt; | |
344 | stmt = tsi_stmt (i); | |
345 | ||
346 | /* If the statement starts a new basic block or if we have determined | |
347 | in a previous pass that we need to create a new block for STMT, do | |
348 | so now. */ | |
349 | if (start_new_block || stmt_starts_bb_p (stmt, prev_stmt)) | |
350 | { | |
351 | if (!first_stmt_of_list) | |
352 | stmt_list = tsi_split_statement_list_before (&i); | |
353 | bb = create_basic_block (stmt_list, NULL, bb); | |
354 | start_new_block = false; | |
355 | } | |
356 | ||
357 | /* Now add STMT to BB and create the subgraphs for special statement | |
358 | codes. */ | |
359 | set_bb_for_stmt (stmt, bb); | |
360 | ||
361 | if (computed_goto_p (stmt)) | |
362 | found_computed_goto = true; | |
363 | ||
364 | /* If STMT is a basic block terminator, set START_NEW_BLOCK for the | |
365 | next iteration. */ | |
366 | if (stmt_ends_bb_p (stmt)) | |
367 | start_new_block = true; | |
368 | ||
369 | tsi_next (&i); | |
370 | first_stmt_of_list = false; | |
371 | } | |
372 | } | |
373 | ||
374 | ||
375 | /* Create and return a new empty basic block after bb AFTER. */ | |
376 | ||
377 | static basic_block | |
378 | create_bb (void *h, void *e, basic_block after) | |
379 | { | |
380 | basic_block bb; | |
381 | ||
1e128c5f | 382 | gcc_assert (!e); |
6de9cd9a | 383 | |
27fd69fa KH |
384 | /* Create and initialize a new basic block. Since alloc_block uses |
385 | ggc_alloc_cleared to allocate a basic block, we do not have to | |
386 | clear the newly allocated basic block here. */ | |
6de9cd9a | 387 | bb = alloc_block (); |
6de9cd9a DN |
388 | |
389 | bb->index = last_basic_block; | |
390 | bb->flags = BB_NEW; | |
858904db | 391 | bb->stmt_list = h ? (tree) h : alloc_stmt_list (); |
6de9cd9a DN |
392 | |
393 | /* Add the new block to the linked list of blocks. */ | |
394 | link_block (bb, after); | |
395 | ||
396 | /* Grow the basic block array if needed. */ | |
68f9b844 | 397 | if ((size_t) last_basic_block == VEC_length (basic_block, basic_block_info)) |
6de9cd9a | 398 | { |
68f9b844 | 399 | size_t old_size = VEC_length (basic_block, basic_block_info); |
6de9cd9a | 400 | size_t new_size = last_basic_block + (last_basic_block + 3) / 4; |
68f9b844 KH |
401 | basic_block *p; |
402 | VEC_safe_grow (basic_block, gc, basic_block_info, new_size); | |
403 | p = VEC_address (basic_block, basic_block_info); | |
404 | memset (&p[old_size], 0, sizeof (basic_block) * (new_size - old_size)); | |
6de9cd9a DN |
405 | } |
406 | ||
407 | /* Add the newly created block to the array. */ | |
68f9b844 | 408 | SET_BASIC_BLOCK (last_basic_block, bb); |
6de9cd9a | 409 | |
6de9cd9a DN |
410 | n_basic_blocks++; |
411 | last_basic_block++; | |
412 | ||
6de9cd9a DN |
413 | return bb; |
414 | } | |
415 | ||
416 | ||
417 | /*--------------------------------------------------------------------------- | |
418 | Edge creation | |
419 | ---------------------------------------------------------------------------*/ | |
420 | ||
fca01525 KH |
421 | /* Fold COND_EXPR_COND of each COND_EXPR. */ |
422 | ||
e21aff8a | 423 | void |
fca01525 KH |
424 | fold_cond_expr_cond (void) |
425 | { | |
426 | basic_block bb; | |
427 | ||
428 | FOR_EACH_BB (bb) | |
429 | { | |
430 | tree stmt = last_stmt (bb); | |
431 | ||
432 | if (stmt | |
433 | && TREE_CODE (stmt) == COND_EXPR) | |
434 | { | |
435 | tree cond = fold (COND_EXPR_COND (stmt)); | |
436 | if (integer_zerop (cond)) | |
4bafe847 | 437 | COND_EXPR_COND (stmt) = boolean_false_node; |
fca01525 | 438 | else if (integer_onep (cond)) |
4bafe847 | 439 | COND_EXPR_COND (stmt) = boolean_true_node; |
fca01525 KH |
440 | } |
441 | } | |
442 | } | |
443 | ||
6de9cd9a DN |
444 | /* Join all the blocks in the flowgraph. */ |
445 | ||
446 | static void | |
447 | make_edges (void) | |
448 | { | |
449 | basic_block bb; | |
bed575d5 | 450 | struct omp_region *cur_region = NULL; |
6de9cd9a DN |
451 | |
452 | /* Create an edge from entry to the first block with executable | |
453 | statements in it. */ | |
24bd1a0b | 454 | make_edge (ENTRY_BLOCK_PTR, BASIC_BLOCK (NUM_FIXED_BLOCKS), EDGE_FALLTHRU); |
6de9cd9a | 455 | |
adb35797 | 456 | /* Traverse the basic block array placing edges. */ |
6de9cd9a DN |
457 | FOR_EACH_BB (bb) |
458 | { | |
6de9cd9a | 459 | tree last = last_stmt (bb); |
56e84019 | 460 | bool fallthru; |
6de9cd9a | 461 | |
56e84019 | 462 | if (last) |
6de9cd9a | 463 | { |
bed575d5 RS |
464 | enum tree_code code = TREE_CODE (last); |
465 | switch (code) | |
56e84019 RH |
466 | { |
467 | case GOTO_EXPR: | |
468 | make_goto_expr_edges (bb); | |
469 | fallthru = false; | |
470 | break; | |
471 | case RETURN_EXPR: | |
472 | make_edge (bb, EXIT_BLOCK_PTR, 0); | |
473 | fallthru = false; | |
474 | break; | |
475 | case COND_EXPR: | |
476 | make_cond_expr_edges (bb); | |
477 | fallthru = false; | |
478 | break; | |
479 | case SWITCH_EXPR: | |
480 | make_switch_expr_edges (bb); | |
481 | fallthru = false; | |
482 | break; | |
483 | case RESX_EXPR: | |
484 | make_eh_edges (last); | |
485 | fallthru = false; | |
486 | break; | |
487 | ||
488 | case CALL_EXPR: | |
489 | /* If this function receives a nonlocal goto, then we need to | |
490 | make edges from this call site to all the nonlocal goto | |
491 | handlers. */ | |
4f6c2131 EB |
492 | if (tree_can_make_abnormal_goto (last)) |
493 | make_abnormal_goto_edges (bb, true); | |
6de9cd9a | 494 | |
56e84019 RH |
495 | /* If this statement has reachable exception handlers, then |
496 | create abnormal edges to them. */ | |
497 | make_eh_edges (last); | |
498 | ||
499 | /* Some calls are known not to return. */ | |
500 | fallthru = !(call_expr_flags (last) & ECF_NORETURN); | |
501 | break; | |
502 | ||
503 | case MODIFY_EXPR: | |
07beea0d AH |
504 | gcc_unreachable (); |
505 | ||
506 | case GIMPLE_MODIFY_STMT: | |
56e84019 RH |
507 | if (is_ctrl_altering_stmt (last)) |
508 | { | |
07beea0d AH |
509 | /* A GIMPLE_MODIFY_STMT may have a CALL_EXPR on its RHS and |
510 | the CALL_EXPR may have an abnormal edge. Search the RHS | |
511 | for this case and create any required edges. */ | |
4f6c2131 EB |
512 | if (tree_can_make_abnormal_goto (last)) |
513 | make_abnormal_goto_edges (bb, true); | |
56e84019 RH |
514 | |
515 | make_eh_edges (last); | |
516 | } | |
517 | fallthru = true; | |
518 | break; | |
519 | ||
520 | case OMP_PARALLEL: | |
521 | case OMP_FOR: | |
522 | case OMP_SINGLE: | |
523 | case OMP_MASTER: | |
524 | case OMP_ORDERED: | |
525 | case OMP_CRITICAL: | |
526 | case OMP_SECTION: | |
bed575d5 | 527 | cur_region = new_omp_region (bb, code, cur_region); |
56e84019 RH |
528 | fallthru = true; |
529 | break; | |
530 | ||
7e2df4a1 | 531 | case OMP_SECTIONS: |
bed575d5 | 532 | cur_region = new_omp_region (bb, code, cur_region); |
7e2df4a1 | 533 | fallthru = false; |
777f7f9a RH |
534 | break; |
535 | ||
bed575d5 RS |
536 | case OMP_RETURN: |
537 | /* In the case of an OMP_SECTION, the edge will go somewhere | |
538 | other than the next block. This will be created later. */ | |
539 | cur_region->exit = bb; | |
540 | fallthru = cur_region->type != OMP_SECTION; | |
541 | cur_region = cur_region->outer; | |
542 | break; | |
543 | ||
544 | case OMP_CONTINUE: | |
545 | cur_region->cont = bb; | |
546 | switch (cur_region->type) | |
547 | { | |
548 | case OMP_FOR: | |
549 | /* ??? Technically there should be a some sort of loopback | |
550 | edge here, but it goes to a block that doesn't exist yet, | |
551 | and without it, updating the ssa form would be a real | |
552 | bear. Fortunately, we don't yet do ssa before expanding | |
553 | these nodes. */ | |
554 | break; | |
555 | ||
556 | case OMP_SECTIONS: | |
557 | /* Wire up the edges into and out of the nested sections. */ | |
558 | /* ??? Similarly wrt loopback. */ | |
559 | { | |
560 | struct omp_region *i; | |
561 | for (i = cur_region->inner; i ; i = i->next) | |
562 | { | |
563 | gcc_assert (i->type == OMP_SECTION); | |
564 | make_edge (cur_region->entry, i->entry, 0); | |
565 | make_edge (i->exit, bb, EDGE_FALLTHRU); | |
566 | } | |
567 | } | |
568 | break; | |
6531d1be | 569 | |
bed575d5 RS |
570 | default: |
571 | gcc_unreachable (); | |
572 | } | |
573 | fallthru = true; | |
574 | break; | |
575 | ||
56e84019 RH |
576 | default: |
577 | gcc_assert (!stmt_ends_bb_p (last)); | |
578 | fallthru = true; | |
579 | } | |
6de9cd9a | 580 | } |
56e84019 RH |
581 | else |
582 | fallthru = true; | |
6de9cd9a | 583 | |
56e84019 | 584 | if (fallthru) |
6de9cd9a DN |
585 | make_edge (bb, bb->next_bb, EDGE_FALLTHRU); |
586 | } | |
587 | ||
bed575d5 RS |
588 | if (root_omp_region) |
589 | free_omp_regions (); | |
590 | ||
fca01525 KH |
591 | /* Fold COND_EXPR_COND of each COND_EXPR. */ |
592 | fold_cond_expr_cond (); | |
593 | ||
6de9cd9a DN |
594 | /* Clean up the graph and warn for unreachable code. */ |
595 | cleanup_tree_cfg (); | |
596 | } | |
597 | ||
598 | ||
6de9cd9a DN |
599 | /* Create the edges for a COND_EXPR starting at block BB. |
600 | At this point, both clauses must contain only simple gotos. */ | |
601 | ||
602 | static void | |
603 | make_cond_expr_edges (basic_block bb) | |
604 | { | |
605 | tree entry = last_stmt (bb); | |
606 | basic_block then_bb, else_bb; | |
607 | tree then_label, else_label; | |
d783b2a2 | 608 | edge e; |
6de9cd9a | 609 | |
1e128c5f GB |
610 | gcc_assert (entry); |
611 | gcc_assert (TREE_CODE (entry) == COND_EXPR); | |
6de9cd9a DN |
612 | |
613 | /* Entry basic blocks for each component. */ | |
614 | then_label = GOTO_DESTINATION (COND_EXPR_THEN (entry)); | |
615 | else_label = GOTO_DESTINATION (COND_EXPR_ELSE (entry)); | |
616 | then_bb = label_to_block (then_label); | |
617 | else_bb = label_to_block (else_label); | |
618 | ||
d783b2a2 JH |
619 | e = make_edge (bb, then_bb, EDGE_TRUE_VALUE); |
620 | #ifdef USE_MAPPED_LOCATION | |
621 | e->goto_locus = EXPR_LOCATION (COND_EXPR_THEN (entry)); | |
622 | #else | |
623 | e->goto_locus = EXPR_LOCUS (COND_EXPR_THEN (entry)); | |
624 | #endif | |
625 | e = make_edge (bb, else_bb, EDGE_FALSE_VALUE); | |
626 | if (e) | |
627 | { | |
628 | #ifdef USE_MAPPED_LOCATION | |
629 | e->goto_locus = EXPR_LOCATION (COND_EXPR_ELSE (entry)); | |
630 | #else | |
631 | e->goto_locus = EXPR_LOCUS (COND_EXPR_ELSE (entry)); | |
632 | #endif | |
633 | } | |
6de9cd9a DN |
634 | } |
635 | ||
d6be0d7f | 636 | /* Hashing routine for EDGE_TO_CASES. */ |
92b6dff3 JL |
637 | |
638 | static hashval_t | |
d6be0d7f | 639 | edge_to_cases_hash (const void *p) |
92b6dff3 | 640 | { |
d6be0d7f | 641 | edge e = ((struct edge_to_cases_elt *)p)->e; |
92b6dff3 JL |
642 | |
643 | /* Hash on the edge itself (which is a pointer). */ | |
644 | return htab_hash_pointer (e); | |
645 | } | |
646 | ||
d6be0d7f | 647 | /* Equality routine for EDGE_TO_CASES, edges are unique, so testing |
92b6dff3 JL |
648 | for equality is just a pointer comparison. */ |
649 | ||
650 | static int | |
d6be0d7f | 651 | edge_to_cases_eq (const void *p1, const void *p2) |
92b6dff3 | 652 | { |
d6be0d7f JL |
653 | edge e1 = ((struct edge_to_cases_elt *)p1)->e; |
654 | edge e2 = ((struct edge_to_cases_elt *)p2)->e; | |
92b6dff3 JL |
655 | |
656 | return e1 == e2; | |
657 | } | |
658 | ||
d6be0d7f JL |
659 | /* Called for each element in the hash table (P) as we delete the |
660 | edge to cases hash table. | |
661 | ||
6531d1be | 662 | Clear all the TREE_CHAINs to prevent problems with copying of |
d6be0d7f JL |
663 | SWITCH_EXPRs and structure sharing rules, then free the hash table |
664 | element. */ | |
665 | ||
666 | static void | |
667 | edge_to_cases_cleanup (void *p) | |
668 | { | |
858904db | 669 | struct edge_to_cases_elt *elt = (struct edge_to_cases_elt *) p; |
d6be0d7f JL |
670 | tree t, next; |
671 | ||
672 | for (t = elt->case_labels; t; t = next) | |
673 | { | |
674 | next = TREE_CHAIN (t); | |
675 | TREE_CHAIN (t) = NULL; | |
676 | } | |
677 | free (p); | |
678 | } | |
679 | ||
680 | /* Start recording information mapping edges to case labels. */ | |
681 | ||
c9784e6d | 682 | void |
d6be0d7f JL |
683 | start_recording_case_labels (void) |
684 | { | |
685 | gcc_assert (edge_to_cases == NULL); | |
686 | ||
687 | edge_to_cases = htab_create (37, | |
688 | edge_to_cases_hash, | |
689 | edge_to_cases_eq, | |
690 | edge_to_cases_cleanup); | |
691 | } | |
692 | ||
693 | /* Return nonzero if we are recording information for case labels. */ | |
694 | ||
695 | static bool | |
696 | recording_case_labels_p (void) | |
697 | { | |
698 | return (edge_to_cases != NULL); | |
699 | } | |
700 | ||
701 | /* Stop recording information mapping edges to case labels and | |
702 | remove any information we have recorded. */ | |
c9784e6d | 703 | void |
d6be0d7f JL |
704 | end_recording_case_labels (void) |
705 | { | |
706 | htab_delete (edge_to_cases); | |
707 | edge_to_cases = NULL; | |
708 | } | |
709 | ||
92b6dff3 JL |
710 | /* Record that CASE_LABEL (a CASE_LABEL_EXPR) references edge E. */ |
711 | ||
712 | static void | |
713 | record_switch_edge (edge e, tree case_label) | |
714 | { | |
d6be0d7f | 715 | struct edge_to_cases_elt *elt; |
92b6dff3 JL |
716 | void **slot; |
717 | ||
718 | /* Build a hash table element so we can see if E is already | |
719 | in the table. */ | |
858904db | 720 | elt = XNEW (struct edge_to_cases_elt); |
92b6dff3 | 721 | elt->e = e; |
d6be0d7f | 722 | elt->case_labels = case_label; |
92b6dff3 | 723 | |
d6be0d7f | 724 | slot = htab_find_slot (edge_to_cases, elt, INSERT); |
92b6dff3 JL |
725 | |
726 | if (*slot == NULL) | |
727 | { | |
728 | /* E was not in the hash table. Install E into the hash table. */ | |
729 | *slot = (void *)elt; | |
730 | } | |
731 | else | |
732 | { | |
733 | /* E was already in the hash table. Free ELT as we do not need it | |
734 | anymore. */ | |
735 | free (elt); | |
736 | ||
737 | /* Get the entry stored in the hash table. */ | |
d6be0d7f | 738 | elt = (struct edge_to_cases_elt *) *slot; |
92b6dff3 | 739 | |
d6be0d7f JL |
740 | /* Add it to the chain of CASE_LABEL_EXPRs referencing E. */ |
741 | TREE_CHAIN (case_label) = elt->case_labels; | |
742 | elt->case_labels = case_label; | |
92b6dff3 JL |
743 | } |
744 | } | |
745 | ||
d6be0d7f JL |
746 | /* If we are inside a {start,end}_recording_cases block, then return |
747 | a chain of CASE_LABEL_EXPRs from T which reference E. | |
748 | ||
749 | Otherwise return NULL. */ | |
92b6dff3 JL |
750 | |
751 | static tree | |
d6be0d7f | 752 | get_cases_for_edge (edge e, tree t) |
92b6dff3 | 753 | { |
d6be0d7f | 754 | struct edge_to_cases_elt elt, *elt_p; |
92b6dff3 | 755 | void **slot; |
d6be0d7f JL |
756 | size_t i, n; |
757 | tree vec; | |
92b6dff3 | 758 | |
d6be0d7f JL |
759 | /* If we are not recording cases, then we do not have CASE_LABEL_EXPR |
760 | chains available. Return NULL so the caller can detect this case. */ | |
761 | if (!recording_case_labels_p ()) | |
762 | return NULL; | |
6531d1be | 763 | |
d6be0d7f | 764 | restart: |
92b6dff3 | 765 | elt.e = e; |
d6be0d7f JL |
766 | elt.case_labels = NULL; |
767 | slot = htab_find_slot (edge_to_cases, &elt, NO_INSERT); | |
92b6dff3 JL |
768 | |
769 | if (slot) | |
770 | { | |
d6be0d7f JL |
771 | elt_p = (struct edge_to_cases_elt *)*slot; |
772 | return elt_p->case_labels; | |
92b6dff3 JL |
773 | } |
774 | ||
d6be0d7f JL |
775 | /* If we did not find E in the hash table, then this must be the first |
776 | time we have been queried for information about E & T. Add all the | |
777 | elements from T to the hash table then perform the query again. */ | |
92b6dff3 | 778 | |
d6be0d7f | 779 | vec = SWITCH_LABELS (t); |
92b6dff3 | 780 | n = TREE_VEC_LENGTH (vec); |
92b6dff3 JL |
781 | for (i = 0; i < n; i++) |
782 | { | |
d6be0d7f JL |
783 | tree lab = CASE_LABEL (TREE_VEC_ELT (vec, i)); |
784 | basic_block label_bb = label_to_block (lab); | |
785 | record_switch_edge (find_edge (e->src, label_bb), TREE_VEC_ELT (vec, i)); | |
92b6dff3 | 786 | } |
d6be0d7f | 787 | goto restart; |
92b6dff3 | 788 | } |
6de9cd9a DN |
789 | |
790 | /* Create the edges for a SWITCH_EXPR starting at block BB. | |
791 | At this point, the switch body has been lowered and the | |
792 | SWITCH_LABELS filled in, so this is in effect a multi-way branch. */ | |
793 | ||
794 | static void | |
795 | make_switch_expr_edges (basic_block bb) | |
796 | { | |
797 | tree entry = last_stmt (bb); | |
798 | size_t i, n; | |
799 | tree vec; | |
800 | ||
801 | vec = SWITCH_LABELS (entry); | |
802 | n = TREE_VEC_LENGTH (vec); | |
803 | ||
804 | for (i = 0; i < n; ++i) | |
805 | { | |
806 | tree lab = CASE_LABEL (TREE_VEC_ELT (vec, i)); | |
807 | basic_block label_bb = label_to_block (lab); | |
d6be0d7f | 808 | make_edge (bb, label_bb, 0); |
6de9cd9a DN |
809 | } |
810 | } | |
811 | ||
812 | ||
813 | /* Return the basic block holding label DEST. */ | |
814 | ||
815 | basic_block | |
997de8ed | 816 | label_to_block_fn (struct function *ifun, tree dest) |
6de9cd9a | 817 | { |
242229bb JH |
818 | int uid = LABEL_DECL_UID (dest); |
819 | ||
f0b698c1 KH |
820 | /* We would die hard when faced by an undefined label. Emit a label to |
821 | the very first basic block. This will hopefully make even the dataflow | |
242229bb JH |
822 | and undefined variable warnings quite right. */ |
823 | if ((errorcount || sorrycount) && uid < 0) | |
824 | { | |
6531d1be | 825 | block_stmt_iterator bsi = |
24bd1a0b | 826 | bsi_start (BASIC_BLOCK (NUM_FIXED_BLOCKS)); |
242229bb JH |
827 | tree stmt; |
828 | ||
829 | stmt = build1 (LABEL_EXPR, void_type_node, dest); | |
830 | bsi_insert_before (&bsi, stmt, BSI_NEW_STMT); | |
831 | uid = LABEL_DECL_UID (dest); | |
832 | } | |
e597f337 KH |
833 | if (VEC_length (basic_block, ifun->cfg->x_label_to_block_map) |
834 | <= (unsigned int) uid) | |
98f464e0 | 835 | return NULL; |
e597f337 | 836 | return VEC_index (basic_block, ifun->cfg->x_label_to_block_map, uid); |
6de9cd9a DN |
837 | } |
838 | ||
4f6c2131 EB |
839 | /* Create edges for an abnormal goto statement at block BB. If FOR_CALL |
840 | is true, the source statement is a CALL_EXPR instead of a GOTO_EXPR. */ | |
841 | ||
842 | void | |
843 | make_abnormal_goto_edges (basic_block bb, bool for_call) | |
844 | { | |
845 | basic_block target_bb; | |
846 | block_stmt_iterator bsi; | |
847 | ||
848 | FOR_EACH_BB (target_bb) | |
849 | for (bsi = bsi_start (target_bb); !bsi_end_p (bsi); bsi_next (&bsi)) | |
850 | { | |
851 | tree target = bsi_stmt (bsi); | |
852 | ||
853 | if (TREE_CODE (target) != LABEL_EXPR) | |
854 | break; | |
855 | ||
856 | target = LABEL_EXPR_LABEL (target); | |
857 | ||
858 | /* Make an edge to every label block that has been marked as a | |
859 | potential target for a computed goto or a non-local goto. */ | |
860 | if ((FORCED_LABEL (target) && !for_call) | |
861 | || (DECL_NONLOCAL (target) && for_call)) | |
862 | { | |
863 | make_edge (bb, target_bb, EDGE_ABNORMAL); | |
864 | break; | |
865 | } | |
866 | } | |
867 | } | |
868 | ||
6de9cd9a DN |
869 | /* Create edges for a goto statement at block BB. */ |
870 | ||
871 | static void | |
872 | make_goto_expr_edges (basic_block bb) | |
873 | { | |
6de9cd9a | 874 | block_stmt_iterator last = bsi_last (bb); |
4f6c2131 | 875 | tree goto_t = bsi_stmt (last); |
6de9cd9a | 876 | |
4f6c2131 EB |
877 | /* A simple GOTO creates normal edges. */ |
878 | if (simple_goto_p (goto_t)) | |
6de9cd9a | 879 | { |
7d3bf067 | 880 | tree dest = GOTO_DESTINATION (goto_t); |
4f6c2131 | 881 | edge e = make_edge (bb, label_to_block (dest), EDGE_FALLTHRU); |
9506ac2b | 882 | #ifdef USE_MAPPED_LOCATION |
4f6c2131 | 883 | e->goto_locus = EXPR_LOCATION (goto_t); |
9506ac2b | 884 | #else |
4f6c2131 | 885 | e->goto_locus = EXPR_LOCUS (goto_t); |
9506ac2b | 886 | #endif |
4f6c2131 EB |
887 | bsi_remove (&last, true); |
888 | return; | |
6de9cd9a DN |
889 | } |
890 | ||
4f6c2131 EB |
891 | /* A computed GOTO creates abnormal edges. */ |
892 | make_abnormal_goto_edges (bb, false); | |
6de9cd9a DN |
893 | } |
894 | ||
895 | ||
896 | /*--------------------------------------------------------------------------- | |
897 | Flowgraph analysis | |
898 | ---------------------------------------------------------------------------*/ | |
899 | ||
f698d217 SB |
900 | /* Cleanup useless labels in basic blocks. This is something we wish |
901 | to do early because it allows us to group case labels before creating | |
902 | the edges for the CFG, and it speeds up block statement iterators in | |
903 | all passes later on. | |
904 | We only run this pass once, running it more than once is probably not | |
905 | profitable. */ | |
906 | ||
907 | /* A map from basic block index to the leading label of that block. */ | |
908 | static tree *label_for_bb; | |
909 | ||
910 | /* Callback for for_each_eh_region. Helper for cleanup_dead_labels. */ | |
911 | static void | |
912 | update_eh_label (struct eh_region *region) | |
913 | { | |
914 | tree old_label = get_eh_region_tree_label (region); | |
915 | if (old_label) | |
916 | { | |
165b54c3 SB |
917 | tree new_label; |
918 | basic_block bb = label_to_block (old_label); | |
919 | ||
920 | /* ??? After optimizing, there may be EH regions with labels | |
921 | that have already been removed from the function body, so | |
922 | there is no basic block for them. */ | |
923 | if (! bb) | |
924 | return; | |
925 | ||
926 | new_label = label_for_bb[bb->index]; | |
f698d217 SB |
927 | set_eh_region_tree_label (region, new_label); |
928 | } | |
929 | } | |
930 | ||
242229bb JH |
931 | /* Given LABEL return the first label in the same basic block. */ |
932 | static tree | |
933 | main_block_label (tree label) | |
934 | { | |
935 | basic_block bb = label_to_block (label); | |
936 | ||
937 | /* label_to_block possibly inserted undefined label into the chain. */ | |
938 | if (!label_for_bb[bb->index]) | |
939 | label_for_bb[bb->index] = label; | |
940 | return label_for_bb[bb->index]; | |
941 | } | |
942 | ||
b986ebf3 | 943 | /* Cleanup redundant labels. This is a three-step process: |
f698d217 SB |
944 | 1) Find the leading label for each block. |
945 | 2) Redirect all references to labels to the leading labels. | |
946 | 3) Cleanup all useless labels. */ | |
6de9cd9a | 947 | |
165b54c3 | 948 | void |
6de9cd9a DN |
949 | cleanup_dead_labels (void) |
950 | { | |
951 | basic_block bb; | |
858904db | 952 | label_for_bb = XCNEWVEC (tree, last_basic_block); |
6de9cd9a DN |
953 | |
954 | /* Find a suitable label for each block. We use the first user-defined | |
f0b698c1 | 955 | label if there is one, or otherwise just the first label we see. */ |
6de9cd9a DN |
956 | FOR_EACH_BB (bb) |
957 | { | |
958 | block_stmt_iterator i; | |
959 | ||
960 | for (i = bsi_start (bb); !bsi_end_p (i); bsi_next (&i)) | |
961 | { | |
962 | tree label, stmt = bsi_stmt (i); | |
963 | ||
964 | if (TREE_CODE (stmt) != LABEL_EXPR) | |
965 | break; | |
966 | ||
967 | label = LABEL_EXPR_LABEL (stmt); | |
968 | ||
969 | /* If we have not yet seen a label for the current block, | |
970 | remember this one and see if there are more labels. */ | |
971 | if (! label_for_bb[bb->index]) | |
972 | { | |
973 | label_for_bb[bb->index] = label; | |
974 | continue; | |
975 | } | |
976 | ||
977 | /* If we did see a label for the current block already, but it | |
978 | is an artificially created label, replace it if the current | |
979 | label is a user defined label. */ | |
980 | if (! DECL_ARTIFICIAL (label) | |
981 | && DECL_ARTIFICIAL (label_for_bb[bb->index])) | |
982 | { | |
983 | label_for_bb[bb->index] = label; | |
984 | break; | |
985 | } | |
986 | } | |
987 | } | |
988 | ||
f698d217 SB |
989 | /* Now redirect all jumps/branches to the selected label. |
990 | First do so for each block ending in a control statement. */ | |
6de9cd9a DN |
991 | FOR_EACH_BB (bb) |
992 | { | |
993 | tree stmt = last_stmt (bb); | |
994 | if (!stmt) | |
995 | continue; | |
996 | ||
997 | switch (TREE_CODE (stmt)) | |
998 | { | |
999 | case COND_EXPR: | |
1000 | { | |
1001 | tree true_branch, false_branch; | |
6de9cd9a DN |
1002 | |
1003 | true_branch = COND_EXPR_THEN (stmt); | |
1004 | false_branch = COND_EXPR_ELSE (stmt); | |
6de9cd9a | 1005 | |
242229bb JH |
1006 | GOTO_DESTINATION (true_branch) |
1007 | = main_block_label (GOTO_DESTINATION (true_branch)); | |
1008 | GOTO_DESTINATION (false_branch) | |
1009 | = main_block_label (GOTO_DESTINATION (false_branch)); | |
6de9cd9a DN |
1010 | |
1011 | break; | |
1012 | } | |
6531d1be | 1013 | |
6de9cd9a DN |
1014 | case SWITCH_EXPR: |
1015 | { | |
1016 | size_t i; | |
1017 | tree vec = SWITCH_LABELS (stmt); | |
1018 | size_t n = TREE_VEC_LENGTH (vec); | |
6531d1be | 1019 | |
6de9cd9a DN |
1020 | /* Replace all destination labels. */ |
1021 | for (i = 0; i < n; ++i) | |
92b6dff3 JL |
1022 | { |
1023 | tree elt = TREE_VEC_ELT (vec, i); | |
1024 | tree label = main_block_label (CASE_LABEL (elt)); | |
d6be0d7f | 1025 | CASE_LABEL (elt) = label; |
92b6dff3 | 1026 | } |
6de9cd9a DN |
1027 | break; |
1028 | } | |
1029 | ||
f667741c SB |
1030 | /* We have to handle GOTO_EXPRs until they're removed, and we don't |
1031 | remove them until after we've created the CFG edges. */ | |
1032 | case GOTO_EXPR: | |
242229bb JH |
1033 | if (! computed_goto_p (stmt)) |
1034 | { | |
1035 | GOTO_DESTINATION (stmt) | |
1036 | = main_block_label (GOTO_DESTINATION (stmt)); | |
1037 | break; | |
1038 | } | |
f667741c | 1039 | |
6de9cd9a DN |
1040 | default: |
1041 | break; | |
1042 | } | |
1043 | } | |
1044 | ||
f698d217 SB |
1045 | for_each_eh_region (update_eh_label); |
1046 | ||
6de9cd9a | 1047 | /* Finally, purge dead labels. All user-defined labels and labels that |
cea0f4f1 AP |
1048 | can be the target of non-local gotos and labels which have their |
1049 | address taken are preserved. */ | |
6de9cd9a DN |
1050 | FOR_EACH_BB (bb) |
1051 | { | |
1052 | block_stmt_iterator i; | |
1053 | tree label_for_this_bb = label_for_bb[bb->index]; | |
1054 | ||
1055 | if (! label_for_this_bb) | |
1056 | continue; | |
1057 | ||
1058 | for (i = bsi_start (bb); !bsi_end_p (i); ) | |
1059 | { | |
1060 | tree label, stmt = bsi_stmt (i); | |
1061 | ||
1062 | if (TREE_CODE (stmt) != LABEL_EXPR) | |
1063 | break; | |
1064 | ||
1065 | label = LABEL_EXPR_LABEL (stmt); | |
1066 | ||
1067 | if (label == label_for_this_bb | |
1068 | || ! DECL_ARTIFICIAL (label) | |
cea0f4f1 AP |
1069 | || DECL_NONLOCAL (label) |
1070 | || FORCED_LABEL (label)) | |
6de9cd9a DN |
1071 | bsi_next (&i); |
1072 | else | |
736432ee | 1073 | bsi_remove (&i, true); |
6de9cd9a DN |
1074 | } |
1075 | } | |
1076 | ||
1077 | free (label_for_bb); | |
1078 | } | |
1079 | ||
f667741c SB |
1080 | /* Look for blocks ending in a multiway branch (a SWITCH_EXPR in GIMPLE), |
1081 | and scan the sorted vector of cases. Combine the ones jumping to the | |
1082 | same label. | |
1083 | Eg. three separate entries 1: 2: 3: become one entry 1..3: */ | |
1084 | ||
165b54c3 | 1085 | void |
f667741c SB |
1086 | group_case_labels (void) |
1087 | { | |
1088 | basic_block bb; | |
1089 | ||
1090 | FOR_EACH_BB (bb) | |
1091 | { | |
1092 | tree stmt = last_stmt (bb); | |
1093 | if (stmt && TREE_CODE (stmt) == SWITCH_EXPR) | |
1094 | { | |
1095 | tree labels = SWITCH_LABELS (stmt); | |
1096 | int old_size = TREE_VEC_LENGTH (labels); | |
1097 | int i, j, new_size = old_size; | |
29c4d22b | 1098 | tree default_case = TREE_VEC_ELT (labels, old_size - 1); |
6531d1be | 1099 | tree default_label; |
29c4d22b | 1100 | |
66efeafc | 1101 | /* The default label is always the last case in a switch |
29c4d22b AP |
1102 | statement after gimplification. */ |
1103 | default_label = CASE_LABEL (default_case); | |
f667741c SB |
1104 | |
1105 | /* Look for possible opportunities to merge cases. | |
1106 | Ignore the last element of the label vector because it | |
1107 | must be the default case. */ | |
1108 | i = 0; | |
d717e500 | 1109 | while (i < old_size - 1) |
f667741c | 1110 | { |
ed9cef22 | 1111 | tree base_case, base_label, base_high; |
f667741c SB |
1112 | base_case = TREE_VEC_ELT (labels, i); |
1113 | ||
1e128c5f | 1114 | gcc_assert (base_case); |
f667741c | 1115 | base_label = CASE_LABEL (base_case); |
31e9eea2 SB |
1116 | |
1117 | /* Discard cases that have the same destination as the | |
1118 | default case. */ | |
1119 | if (base_label == default_label) | |
1120 | { | |
1121 | TREE_VEC_ELT (labels, i) = NULL_TREE; | |
1122 | i++; | |
29c4d22b | 1123 | new_size--; |
31e9eea2 SB |
1124 | continue; |
1125 | } | |
1126 | ||
f667741c SB |
1127 | base_high = CASE_HIGH (base_case) ? |
1128 | CASE_HIGH (base_case) : CASE_LOW (base_case); | |
d717e500 | 1129 | i++; |
f667741c SB |
1130 | /* Try to merge case labels. Break out when we reach the end |
1131 | of the label vector or when we cannot merge the next case | |
1132 | label with the current one. */ | |
d717e500 | 1133 | while (i < old_size - 1) |
f667741c | 1134 | { |
d717e500 | 1135 | tree merge_case = TREE_VEC_ELT (labels, i); |
f667741c SB |
1136 | tree merge_label = CASE_LABEL (merge_case); |
1137 | tree t = int_const_binop (PLUS_EXPR, base_high, | |
1138 | integer_one_node, 1); | |
1139 | ||
1140 | /* Merge the cases if they jump to the same place, | |
1141 | and their ranges are consecutive. */ | |
1142 | if (merge_label == base_label | |
1143 | && tree_int_cst_equal (CASE_LOW (merge_case), t)) | |
1144 | { | |
1145 | base_high = CASE_HIGH (merge_case) ? | |
1146 | CASE_HIGH (merge_case) : CASE_LOW (merge_case); | |
1147 | CASE_HIGH (base_case) = base_high; | |
1148 | TREE_VEC_ELT (labels, i) = NULL_TREE; | |
1149 | new_size--; | |
d717e500 | 1150 | i++; |
f667741c SB |
1151 | } |
1152 | else | |
1153 | break; | |
1154 | } | |
1155 | } | |
1156 | ||
1157 | /* Compress the case labels in the label vector, and adjust the | |
1158 | length of the vector. */ | |
1159 | for (i = 0, j = 0; i < new_size; i++) | |
1160 | { | |
1161 | while (! TREE_VEC_ELT (labels, j)) | |
1162 | j++; | |
1163 | TREE_VEC_ELT (labels, i) = TREE_VEC_ELT (labels, j++); | |
1164 | } | |
1165 | TREE_VEC_LENGTH (labels) = new_size; | |
1166 | } | |
1167 | } | |
1168 | } | |
6de9cd9a DN |
1169 | |
1170 | /* Checks whether we can merge block B into block A. */ | |
1171 | ||
1172 | static bool | |
1173 | tree_can_merge_blocks_p (basic_block a, basic_block b) | |
1174 | { | |
1175 | tree stmt; | |
1176 | block_stmt_iterator bsi; | |
38965eb2 | 1177 | tree phi; |
6de9cd9a | 1178 | |
c5cbcccf | 1179 | if (!single_succ_p (a)) |
6de9cd9a DN |
1180 | return false; |
1181 | ||
c5cbcccf | 1182 | if (single_succ_edge (a)->flags & EDGE_ABNORMAL) |
6de9cd9a DN |
1183 | return false; |
1184 | ||
c5cbcccf | 1185 | if (single_succ (a) != b) |
6de9cd9a DN |
1186 | return false; |
1187 | ||
c5cbcccf | 1188 | if (!single_pred_p (b)) |
6de9cd9a DN |
1189 | return false; |
1190 | ||
26e75214 KH |
1191 | if (b == EXIT_BLOCK_PTR) |
1192 | return false; | |
6531d1be | 1193 | |
6de9cd9a DN |
1194 | /* If A ends by a statement causing exceptions or something similar, we |
1195 | cannot merge the blocks. */ | |
1196 | stmt = last_stmt (a); | |
1197 | if (stmt && stmt_ends_bb_p (stmt)) | |
1198 | return false; | |
1199 | ||
1200 | /* Do not allow a block with only a non-local label to be merged. */ | |
1201 | if (stmt && TREE_CODE (stmt) == LABEL_EXPR | |
1202 | && DECL_NONLOCAL (LABEL_EXPR_LABEL (stmt))) | |
1203 | return false; | |
1204 | ||
38965eb2 | 1205 | /* It must be possible to eliminate all phi nodes in B. If ssa form |
8f8bb1d2 ZD |
1206 | is not up-to-date, we cannot eliminate any phis; however, if only |
1207 | some symbols as whole are marked for renaming, this is not a problem, | |
1208 | as phi nodes for those symbols are irrelevant in updating anyway. */ | |
38965eb2 ZD |
1209 | phi = phi_nodes (b); |
1210 | if (phi) | |
1211 | { | |
8f8bb1d2 | 1212 | if (name_mappings_registered_p ()) |
38965eb2 ZD |
1213 | return false; |
1214 | ||
1215 | for (; phi; phi = PHI_CHAIN (phi)) | |
1216 | if (!is_gimple_reg (PHI_RESULT (phi)) | |
1217 | && !may_propagate_copy (PHI_RESULT (phi), PHI_ARG_DEF (phi, 0))) | |
1218 | return false; | |
1219 | } | |
6de9cd9a DN |
1220 | |
1221 | /* Do not remove user labels. */ | |
1222 | for (bsi = bsi_start (b); !bsi_end_p (bsi); bsi_next (&bsi)) | |
1223 | { | |
1224 | stmt = bsi_stmt (bsi); | |
1225 | if (TREE_CODE (stmt) != LABEL_EXPR) | |
1226 | break; | |
1227 | if (!DECL_ARTIFICIAL (LABEL_EXPR_LABEL (stmt))) | |
1228 | return false; | |
1229 | } | |
1230 | ||
2b271002 ZD |
1231 | /* Protect the loop latches. */ |
1232 | if (current_loops | |
1233 | && b->loop_father->latch == b) | |
1234 | return false; | |
1235 | ||
6de9cd9a DN |
1236 | return true; |
1237 | } | |
1238 | ||
38965eb2 ZD |
1239 | /* Replaces all uses of NAME by VAL. */ |
1240 | ||
684aaf29 | 1241 | void |
38965eb2 ZD |
1242 | replace_uses_by (tree name, tree val) |
1243 | { | |
1244 | imm_use_iterator imm_iter; | |
1245 | use_operand_p use; | |
1246 | tree stmt; | |
1247 | edge e; | |
38965eb2 | 1248 | |
6c00f606 | 1249 | FOR_EACH_IMM_USE_STMT (stmt, imm_iter, name) |
38965eb2 | 1250 | { |
cfaab3a9 DN |
1251 | if (TREE_CODE (stmt) != PHI_NODE) |
1252 | push_stmt_changes (&stmt); | |
1253 | ||
6c00f606 AM |
1254 | FOR_EACH_IMM_USE_ON_STMT (use, imm_iter) |
1255 | { | |
1256 | replace_exp (use, val); | |
38965eb2 | 1257 | |
6c00f606 | 1258 | if (TREE_CODE (stmt) == PHI_NODE) |
38965eb2 | 1259 | { |
6c00f606 AM |
1260 | e = PHI_ARG_EDGE (stmt, PHI_ARG_INDEX_FROM_USE (use)); |
1261 | if (e->flags & EDGE_ABNORMAL) | |
1262 | { | |
1263 | /* This can only occur for virtual operands, since | |
1264 | for the real ones SSA_NAME_OCCURS_IN_ABNORMAL_PHI (name)) | |
1265 | would prevent replacement. */ | |
1266 | gcc_assert (!is_gimple_reg (name)); | |
1267 | SSA_NAME_OCCURS_IN_ABNORMAL_PHI (val) = 1; | |
1268 | } | |
38965eb2 ZD |
1269 | } |
1270 | } | |
cfaab3a9 | 1271 | |
6c00f606 AM |
1272 | if (TREE_CODE (stmt) != PHI_NODE) |
1273 | { | |
1274 | tree rhs; | |
9af0df6b | 1275 | |
6c00f606 | 1276 | fold_stmt_inplace (stmt); |
cfaab3a9 DN |
1277 | |
1278 | /* FIXME. This should go in pop_stmt_changes. */ | |
6c00f606 AM |
1279 | rhs = get_rhs (stmt); |
1280 | if (TREE_CODE (rhs) == ADDR_EXPR) | |
1281 | recompute_tree_invariant_for_addr_expr (rhs); | |
9af0df6b | 1282 | |
6c00f606 | 1283 | maybe_clean_or_replace_eh_stmt (stmt, stmt); |
cfaab3a9 DN |
1284 | |
1285 | pop_stmt_changes (&stmt); | |
6c00f606 | 1286 | } |
38965eb2 | 1287 | } |
6531d1be | 1288 | |
cfaab3a9 | 1289 | gcc_assert (zero_imm_uses_p (name)); |
d5ab5675 ZD |
1290 | |
1291 | /* Also update the trees stored in loop structures. */ | |
1292 | if (current_loops) | |
1293 | { | |
1294 | struct loop *loop; | |
42fd6772 | 1295 | loop_iterator li; |
d5ab5675 | 1296 | |
42fd6772 | 1297 | FOR_EACH_LOOP (li, loop, 0) |
d5ab5675 | 1298 | { |
42fd6772 | 1299 | substitute_in_loop_info (loop, name, val); |
d5ab5675 ZD |
1300 | } |
1301 | } | |
38965eb2 | 1302 | } |
6de9cd9a DN |
1303 | |
1304 | /* Merge block B into block A. */ | |
1305 | ||
1306 | static void | |
1307 | tree_merge_blocks (basic_block a, basic_block b) | |
1308 | { | |
1309 | block_stmt_iterator bsi; | |
1310 | tree_stmt_iterator last; | |
38965eb2 | 1311 | tree phi; |
6de9cd9a DN |
1312 | |
1313 | if (dump_file) | |
1314 | fprintf (dump_file, "Merging blocks %d and %d\n", a->index, b->index); | |
1315 | ||
c4f548b8 DN |
1316 | /* Remove all single-valued PHI nodes from block B of the form |
1317 | V_i = PHI <V_j> by propagating V_j to all the uses of V_i. */ | |
38965eb2 ZD |
1318 | bsi = bsi_last (a); |
1319 | for (phi = phi_nodes (b); phi; phi = phi_nodes (b)) | |
1320 | { | |
1321 | tree def = PHI_RESULT (phi), use = PHI_ARG_DEF (phi, 0); | |
1322 | tree copy; | |
d7f0e25c ZD |
1323 | bool may_replace_uses = may_propagate_copy (def, use); |
1324 | ||
1325 | /* In case we have loops to care about, do not propagate arguments of | |
1326 | loop closed ssa phi nodes. */ | |
1327 | if (current_loops | |
1328 | && is_gimple_reg (def) | |
1329 | && TREE_CODE (use) == SSA_NAME | |
1330 | && a->loop_father != b->loop_father) | |
1331 | may_replace_uses = false; | |
1332 | ||
1333 | if (!may_replace_uses) | |
38965eb2 ZD |
1334 | { |
1335 | gcc_assert (is_gimple_reg (def)); | |
1336 | ||
128a79fb | 1337 | /* Note that just emitting the copies is fine -- there is no problem |
38965eb2 ZD |
1338 | with ordering of phi nodes. This is because A is the single |
1339 | predecessor of B, therefore results of the phi nodes cannot | |
1340 | appear as arguments of the phi nodes. */ | |
07beea0d | 1341 | copy = build2_gimple (GIMPLE_MODIFY_STMT, def, use); |
38965eb2 | 1342 | bsi_insert_after (&bsi, copy, BSI_NEW_STMT); |
38965eb2 ZD |
1343 | SSA_NAME_DEF_STMT (def) = copy; |
1344 | } | |
1345 | else | |
1346 | replace_uses_by (def, use); | |
c4f548b8 | 1347 | |
9b3b55a1 | 1348 | remove_phi_node (phi, NULL, false); |
38965eb2 ZD |
1349 | } |
1350 | ||
6de9cd9a DN |
1351 | /* Ensure that B follows A. */ |
1352 | move_block_after (b, a); | |
1353 | ||
c5cbcccf | 1354 | gcc_assert (single_succ_edge (a)->flags & EDGE_FALLTHRU); |
1e128c5f | 1355 | gcc_assert (!last_stmt (a) || !stmt_ends_bb_p (last_stmt (a))); |
6de9cd9a DN |
1356 | |
1357 | /* Remove labels from B and set bb_for_stmt to A for other statements. */ | |
1358 | for (bsi = bsi_start (b); !bsi_end_p (bsi);) | |
1359 | { | |
1360 | if (TREE_CODE (bsi_stmt (bsi)) == LABEL_EXPR) | |
be477406 JL |
1361 | { |
1362 | tree label = bsi_stmt (bsi); | |
1363 | ||
736432ee | 1364 | bsi_remove (&bsi, false); |
be477406 JL |
1365 | /* Now that we can thread computed gotos, we might have |
1366 | a situation where we have a forced label in block B | |
1367 | However, the label at the start of block B might still be | |
1368 | used in other ways (think about the runtime checking for | |
1369 | Fortran assigned gotos). So we can not just delete the | |
1370 | label. Instead we move the label to the start of block A. */ | |
1371 | if (FORCED_LABEL (LABEL_EXPR_LABEL (label))) | |
1372 | { | |
1373 | block_stmt_iterator dest_bsi = bsi_start (a); | |
1374 | bsi_insert_before (&dest_bsi, label, BSI_NEW_STMT); | |
1375 | } | |
1376 | } | |
6de9cd9a DN |
1377 | else |
1378 | { | |
0a4fe58f | 1379 | change_bb_for_stmt (bsi_stmt (bsi), a); |
6de9cd9a DN |
1380 | bsi_next (&bsi); |
1381 | } | |
1382 | } | |
1383 | ||
1384 | /* Merge the chains. */ | |
1385 | last = tsi_last (a->stmt_list); | |
1386 | tsi_link_after (&last, b->stmt_list, TSI_NEW_STMT); | |
1387 | b->stmt_list = NULL; | |
1388 | } | |
1389 | ||
1390 | ||
bc23502b PB |
1391 | /* Return the one of two successors of BB that is not reachable by a |
1392 | reached by a complex edge, if there is one. Else, return BB. We use | |
1393 | this in optimizations that use post-dominators for their heuristics, | |
1394 | to catch the cases in C++ where function calls are involved. */ | |
6531d1be | 1395 | |
bc23502b | 1396 | basic_block |
6531d1be | 1397 | single_noncomplex_succ (basic_block bb) |
bc23502b PB |
1398 | { |
1399 | edge e0, e1; | |
1400 | if (EDGE_COUNT (bb->succs) != 2) | |
1401 | return bb; | |
6531d1be | 1402 | |
bc23502b PB |
1403 | e0 = EDGE_SUCC (bb, 0); |
1404 | e1 = EDGE_SUCC (bb, 1); | |
1405 | if (e0->flags & EDGE_COMPLEX) | |
1406 | return e1->dest; | |
1407 | if (e1->flags & EDGE_COMPLEX) | |
1408 | return e0->dest; | |
6531d1be | 1409 | |
bc23502b | 1410 | return bb; |
6531d1be | 1411 | } |
bc23502b PB |
1412 | |
1413 | ||
6de9cd9a DN |
1414 | /* Walk the function tree removing unnecessary statements. |
1415 | ||
1416 | * Empty statement nodes are removed | |
1417 | ||
1418 | * Unnecessary TRY_FINALLY and TRY_CATCH blocks are removed | |
1419 | ||
1420 | * Unnecessary COND_EXPRs are removed | |
1421 | ||
1422 | * Some unnecessary BIND_EXPRs are removed | |
1423 | ||
1424 | Clearly more work could be done. The trick is doing the analysis | |
1425 | and removal fast enough to be a net improvement in compile times. | |
1426 | ||
1427 | Note that when we remove a control structure such as a COND_EXPR | |
1428 | BIND_EXPR, or TRY block, we will need to repeat this optimization pass | |
1429 | to ensure we eliminate all the useless code. */ | |
1430 | ||
1431 | struct rus_data | |
1432 | { | |
1433 | tree *last_goto; | |
1434 | bool repeat; | |
1435 | bool may_throw; | |
1436 | bool may_branch; | |
1437 | bool has_label; | |
1438 | }; | |
1439 | ||
1440 | static void remove_useless_stmts_1 (tree *, struct rus_data *); | |
1441 | ||
1442 | static bool | |
1443 | remove_useless_stmts_warn_notreached (tree stmt) | |
1444 | { | |
9506ac2b | 1445 | if (EXPR_HAS_LOCATION (stmt)) |
6de9cd9a | 1446 | { |
9506ac2b | 1447 | location_t loc = EXPR_LOCATION (stmt); |
43e05e45 SB |
1448 | if (LOCATION_LINE (loc) > 0) |
1449 | { | |
d4ee4d25 | 1450 | warning (0, "%Hwill never be executed", &loc); |
43e05e45 SB |
1451 | return true; |
1452 | } | |
6de9cd9a DN |
1453 | } |
1454 | ||
1455 | switch (TREE_CODE (stmt)) | |
1456 | { | |
1457 | case STATEMENT_LIST: | |
1458 | { | |
1459 | tree_stmt_iterator i; | |
1460 | for (i = tsi_start (stmt); !tsi_end_p (i); tsi_next (&i)) | |
1461 | if (remove_useless_stmts_warn_notreached (tsi_stmt (i))) | |
1462 | return true; | |
1463 | } | |
1464 | break; | |
1465 | ||
1466 | case COND_EXPR: | |
1467 | if (remove_useless_stmts_warn_notreached (COND_EXPR_COND (stmt))) | |
1468 | return true; | |
1469 | if (remove_useless_stmts_warn_notreached (COND_EXPR_THEN (stmt))) | |
1470 | return true; | |
1471 | if (remove_useless_stmts_warn_notreached (COND_EXPR_ELSE (stmt))) | |
1472 | return true; | |
1473 | break; | |
1474 | ||
1475 | case TRY_FINALLY_EXPR: | |
1476 | case TRY_CATCH_EXPR: | |
1477 | if (remove_useless_stmts_warn_notreached (TREE_OPERAND (stmt, 0))) | |
1478 | return true; | |
1479 | if (remove_useless_stmts_warn_notreached (TREE_OPERAND (stmt, 1))) | |
1480 | return true; | |
1481 | break; | |
1482 | ||
1483 | case CATCH_EXPR: | |
1484 | return remove_useless_stmts_warn_notreached (CATCH_BODY (stmt)); | |
1485 | case EH_FILTER_EXPR: | |
1486 | return remove_useless_stmts_warn_notreached (EH_FILTER_FAILURE (stmt)); | |
1487 | case BIND_EXPR: | |
1488 | return remove_useless_stmts_warn_notreached (BIND_EXPR_BLOCK (stmt)); | |
1489 | ||
1490 | default: | |
1491 | /* Not a live container. */ | |
1492 | break; | |
1493 | } | |
1494 | ||
1495 | return false; | |
1496 | } | |
1497 | ||
1498 | static void | |
1499 | remove_useless_stmts_cond (tree *stmt_p, struct rus_data *data) | |
1500 | { | |
1501 | tree then_clause, else_clause, cond; | |
1502 | bool save_has_label, then_has_label, else_has_label; | |
1503 | ||
1504 | save_has_label = data->has_label; | |
1505 | data->has_label = false; | |
1506 | data->last_goto = NULL; | |
1507 | ||
1508 | remove_useless_stmts_1 (&COND_EXPR_THEN (*stmt_p), data); | |
1509 | ||
1510 | then_has_label = data->has_label; | |
1511 | data->has_label = false; | |
1512 | data->last_goto = NULL; | |
1513 | ||
1514 | remove_useless_stmts_1 (&COND_EXPR_ELSE (*stmt_p), data); | |
1515 | ||
1516 | else_has_label = data->has_label; | |
1517 | data->has_label = save_has_label | then_has_label | else_has_label; | |
1518 | ||
6de9cd9a DN |
1519 | then_clause = COND_EXPR_THEN (*stmt_p); |
1520 | else_clause = COND_EXPR_ELSE (*stmt_p); | |
18faa5da | 1521 | cond = fold (COND_EXPR_COND (*stmt_p)); |
6de9cd9a DN |
1522 | |
1523 | /* If neither arm does anything at all, we can remove the whole IF. */ | |
1524 | if (!TREE_SIDE_EFFECTS (then_clause) && !TREE_SIDE_EFFECTS (else_clause)) | |
1525 | { | |
1526 | *stmt_p = build_empty_stmt (); | |
1527 | data->repeat = true; | |
1528 | } | |
1529 | ||
1530 | /* If there are no reachable statements in an arm, then we can | |
1531 | zap the entire conditional. */ | |
1532 | else if (integer_nonzerop (cond) && !else_has_label) | |
1533 | { | |
1534 | if (warn_notreached) | |
1535 | remove_useless_stmts_warn_notreached (else_clause); | |
1536 | *stmt_p = then_clause; | |
1537 | data->repeat = true; | |
1538 | } | |
1539 | else if (integer_zerop (cond) && !then_has_label) | |
1540 | { | |
1541 | if (warn_notreached) | |
1542 | remove_useless_stmts_warn_notreached (then_clause); | |
1543 | *stmt_p = else_clause; | |
1544 | data->repeat = true; | |
1545 | } | |
1546 | ||
1547 | /* Check a couple of simple things on then/else with single stmts. */ | |
1548 | else | |
1549 | { | |
1550 | tree then_stmt = expr_only (then_clause); | |
1551 | tree else_stmt = expr_only (else_clause); | |
1552 | ||
1553 | /* Notice branches to a common destination. */ | |
1554 | if (then_stmt && else_stmt | |
1555 | && TREE_CODE (then_stmt) == GOTO_EXPR | |
1556 | && TREE_CODE (else_stmt) == GOTO_EXPR | |
1557 | && (GOTO_DESTINATION (then_stmt) == GOTO_DESTINATION (else_stmt))) | |
1558 | { | |
1559 | *stmt_p = then_stmt; | |
1560 | data->repeat = true; | |
1561 | } | |
1562 | ||
1563 | /* If the THEN/ELSE clause merely assigns a value to a variable or | |
1564 | parameter which is already known to contain that value, then | |
1565 | remove the useless THEN/ELSE clause. */ | |
1566 | else if (TREE_CODE (cond) == VAR_DECL || TREE_CODE (cond) == PARM_DECL) | |
1567 | { | |
1568 | if (else_stmt | |
07beea0d AH |
1569 | && TREE_CODE (else_stmt) == GIMPLE_MODIFY_STMT |
1570 | && GIMPLE_STMT_OPERAND (else_stmt, 0) == cond | |
1571 | && integer_zerop (GIMPLE_STMT_OPERAND (else_stmt, 1))) | |
6de9cd9a DN |
1572 | COND_EXPR_ELSE (*stmt_p) = alloc_stmt_list (); |
1573 | } | |
1574 | else if ((TREE_CODE (cond) == EQ_EXPR || TREE_CODE (cond) == NE_EXPR) | |
1575 | && (TREE_CODE (TREE_OPERAND (cond, 0)) == VAR_DECL | |
1576 | || TREE_CODE (TREE_OPERAND (cond, 0)) == PARM_DECL) | |
1577 | && TREE_CONSTANT (TREE_OPERAND (cond, 1))) | |
1578 | { | |
1579 | tree stmt = (TREE_CODE (cond) == EQ_EXPR | |
1580 | ? then_stmt : else_stmt); | |
1581 | tree *location = (TREE_CODE (cond) == EQ_EXPR | |
1582 | ? &COND_EXPR_THEN (*stmt_p) | |
1583 | : &COND_EXPR_ELSE (*stmt_p)); | |
1584 | ||
1585 | if (stmt | |
07beea0d AH |
1586 | && TREE_CODE (stmt) == GIMPLE_MODIFY_STMT |
1587 | && GIMPLE_STMT_OPERAND (stmt, 0) == TREE_OPERAND (cond, 0) | |
1588 | && GIMPLE_STMT_OPERAND (stmt, 1) == TREE_OPERAND (cond, 1)) | |
6de9cd9a DN |
1589 | *location = alloc_stmt_list (); |
1590 | } | |
1591 | } | |
1592 | ||
1593 | /* Protect GOTOs in the arm of COND_EXPRs from being removed. They | |
1594 | would be re-introduced during lowering. */ | |
1595 | data->last_goto = NULL; | |
1596 | } | |
1597 | ||
1598 | ||
1599 | static void | |
1600 | remove_useless_stmts_tf (tree *stmt_p, struct rus_data *data) | |
1601 | { | |
1602 | bool save_may_branch, save_may_throw; | |
1603 | bool this_may_branch, this_may_throw; | |
1604 | ||
1605 | /* Collect may_branch and may_throw information for the body only. */ | |
1606 | save_may_branch = data->may_branch; | |
1607 | save_may_throw = data->may_throw; | |
1608 | data->may_branch = false; | |
1609 | data->may_throw = false; | |
1610 | data->last_goto = NULL; | |
1611 | ||
1612 | remove_useless_stmts_1 (&TREE_OPERAND (*stmt_p, 0), data); | |
1613 | ||
1614 | this_may_branch = data->may_branch; | |
1615 | this_may_throw = data->may_throw; | |
1616 | data->may_branch |= save_may_branch; | |
1617 | data->may_throw |= save_may_throw; | |
1618 | data->last_goto = NULL; | |
1619 | ||
1620 | remove_useless_stmts_1 (&TREE_OPERAND (*stmt_p, 1), data); | |
1621 | ||
1622 | /* If the body is empty, then we can emit the FINALLY block without | |
1623 | the enclosing TRY_FINALLY_EXPR. */ | |
1624 | if (!TREE_SIDE_EFFECTS (TREE_OPERAND (*stmt_p, 0))) | |
1625 | { | |
1626 | *stmt_p = TREE_OPERAND (*stmt_p, 1); | |
1627 | data->repeat = true; | |
1628 | } | |
1629 | ||
1630 | /* If the handler is empty, then we can emit the TRY block without | |
1631 | the enclosing TRY_FINALLY_EXPR. */ | |
1632 | else if (!TREE_SIDE_EFFECTS (TREE_OPERAND (*stmt_p, 1))) | |
1633 | { | |
1634 | *stmt_p = TREE_OPERAND (*stmt_p, 0); | |
1635 | data->repeat = true; | |
1636 | } | |
1637 | ||
1638 | /* If the body neither throws, nor branches, then we can safely | |
1639 | string the TRY and FINALLY blocks together. */ | |
1640 | else if (!this_may_branch && !this_may_throw) | |
1641 | { | |
1642 | tree stmt = *stmt_p; | |
1643 | *stmt_p = TREE_OPERAND (stmt, 0); | |
1644 | append_to_statement_list (TREE_OPERAND (stmt, 1), stmt_p); | |
1645 | data->repeat = true; | |
1646 | } | |
1647 | } | |
1648 | ||
1649 | ||
1650 | static void | |
1651 | remove_useless_stmts_tc (tree *stmt_p, struct rus_data *data) | |
1652 | { | |
1653 | bool save_may_throw, this_may_throw; | |
1654 | tree_stmt_iterator i; | |
1655 | tree stmt; | |
1656 | ||
1657 | /* Collect may_throw information for the body only. */ | |
1658 | save_may_throw = data->may_throw; | |
1659 | data->may_throw = false; | |
1660 | data->last_goto = NULL; | |
1661 | ||
1662 | remove_useless_stmts_1 (&TREE_OPERAND (*stmt_p, 0), data); | |
1663 | ||
1664 | this_may_throw = data->may_throw; | |
1665 | data->may_throw = save_may_throw; | |
1666 | ||
1667 | /* If the body cannot throw, then we can drop the entire TRY_CATCH_EXPR. */ | |
1668 | if (!this_may_throw) | |
1669 | { | |
1670 | if (warn_notreached) | |
1671 | remove_useless_stmts_warn_notreached (TREE_OPERAND (*stmt_p, 1)); | |
1672 | *stmt_p = TREE_OPERAND (*stmt_p, 0); | |
1673 | data->repeat = true; | |
1674 | return; | |
1675 | } | |
1676 | ||
1677 | /* Process the catch clause specially. We may be able to tell that | |
1678 | no exceptions propagate past this point. */ | |
1679 | ||
1680 | this_may_throw = true; | |
1681 | i = tsi_start (TREE_OPERAND (*stmt_p, 1)); | |
1682 | stmt = tsi_stmt (i); | |
1683 | data->last_goto = NULL; | |
1684 | ||
1685 | switch (TREE_CODE (stmt)) | |
1686 | { | |
1687 | case CATCH_EXPR: | |
1688 | for (; !tsi_end_p (i); tsi_next (&i)) | |
1689 | { | |
1690 | stmt = tsi_stmt (i); | |
1691 | /* If we catch all exceptions, then the body does not | |
1692 | propagate exceptions past this point. */ | |
1693 | if (CATCH_TYPES (stmt) == NULL) | |
1694 | this_may_throw = false; | |
1695 | data->last_goto = NULL; | |
1696 | remove_useless_stmts_1 (&CATCH_BODY (stmt), data); | |
1697 | } | |
1698 | break; | |
1699 | ||
1700 | case EH_FILTER_EXPR: | |
1701 | if (EH_FILTER_MUST_NOT_THROW (stmt)) | |
1702 | this_may_throw = false; | |
1703 | else if (EH_FILTER_TYPES (stmt) == NULL) | |
1704 | this_may_throw = false; | |
1705 | remove_useless_stmts_1 (&EH_FILTER_FAILURE (stmt), data); | |
1706 | break; | |
1707 | ||
1708 | default: | |
1709 | /* Otherwise this is a cleanup. */ | |
1710 | remove_useless_stmts_1 (&TREE_OPERAND (*stmt_p, 1), data); | |
1711 | ||
1712 | /* If the cleanup is empty, then we can emit the TRY block without | |
1713 | the enclosing TRY_CATCH_EXPR. */ | |
1714 | if (!TREE_SIDE_EFFECTS (TREE_OPERAND (*stmt_p, 1))) | |
1715 | { | |
1716 | *stmt_p = TREE_OPERAND (*stmt_p, 0); | |
1717 | data->repeat = true; | |
1718 | } | |
1719 | break; | |
1720 | } | |
1721 | data->may_throw |= this_may_throw; | |
1722 | } | |
1723 | ||
1724 | ||
1725 | static void | |
1726 | remove_useless_stmts_bind (tree *stmt_p, struct rus_data *data) | |
1727 | { | |
1728 | tree block; | |
1729 | ||
1730 | /* First remove anything underneath the BIND_EXPR. */ | |
1731 | remove_useless_stmts_1 (&BIND_EXPR_BODY (*stmt_p), data); | |
1732 | ||
1733 | /* If the BIND_EXPR has no variables, then we can pull everything | |
1734 | up one level and remove the BIND_EXPR, unless this is the toplevel | |
1735 | BIND_EXPR for the current function or an inlined function. | |
1736 | ||
1737 | When this situation occurs we will want to apply this | |
1738 | optimization again. */ | |
1739 | block = BIND_EXPR_BLOCK (*stmt_p); | |
1740 | if (BIND_EXPR_VARS (*stmt_p) == NULL_TREE | |
1741 | && *stmt_p != DECL_SAVED_TREE (current_function_decl) | |
1742 | && (! block | |
1743 | || ! BLOCK_ABSTRACT_ORIGIN (block) | |
1744 | || (TREE_CODE (BLOCK_ABSTRACT_ORIGIN (block)) | |
1745 | != FUNCTION_DECL))) | |
1746 | { | |
1747 | *stmt_p = BIND_EXPR_BODY (*stmt_p); | |
1748 | data->repeat = true; | |
1749 | } | |
1750 | } | |
1751 | ||
1752 | ||
1753 | static void | |
1754 | remove_useless_stmts_goto (tree *stmt_p, struct rus_data *data) | |
1755 | { | |
1756 | tree dest = GOTO_DESTINATION (*stmt_p); | |
1757 | ||
1758 | data->may_branch = true; | |
1759 | data->last_goto = NULL; | |
1760 | ||
1761 | /* Record the last goto expr, so that we can delete it if unnecessary. */ | |
1762 | if (TREE_CODE (dest) == LABEL_DECL) | |
1763 | data->last_goto = stmt_p; | |
1764 | } | |
1765 | ||
1766 | ||
1767 | static void | |
1768 | remove_useless_stmts_label (tree *stmt_p, struct rus_data *data) | |
1769 | { | |
1770 | tree label = LABEL_EXPR_LABEL (*stmt_p); | |
1771 | ||
1772 | data->has_label = true; | |
1773 | ||
1774 | /* We do want to jump across non-local label receiver code. */ | |
1775 | if (DECL_NONLOCAL (label)) | |
1776 | data->last_goto = NULL; | |
1777 | ||
1778 | else if (data->last_goto && GOTO_DESTINATION (*data->last_goto) == label) | |
1779 | { | |
1780 | *data->last_goto = build_empty_stmt (); | |
1781 | data->repeat = true; | |
1782 | } | |
1783 | ||
1784 | /* ??? Add something here to delete unused labels. */ | |
1785 | } | |
1786 | ||
1787 | ||
1788 | /* If the function is "const" or "pure", then clear TREE_SIDE_EFFECTS on its | |
1789 | decl. This allows us to eliminate redundant or useless | |
6531d1be | 1790 | calls to "const" functions. |
6de9cd9a DN |
1791 | |
1792 | Gimplifier already does the same operation, but we may notice functions | |
1793 | being const and pure once their calls has been gimplified, so we need | |
1794 | to update the flag. */ | |
1795 | ||
1796 | static void | |
1797 | update_call_expr_flags (tree call) | |
1798 | { | |
1799 | tree decl = get_callee_fndecl (call); | |
1800 | if (!decl) | |
1801 | return; | |
1802 | if (call_expr_flags (call) & (ECF_CONST | ECF_PURE)) | |
1803 | TREE_SIDE_EFFECTS (call) = 0; | |
1804 | if (TREE_NOTHROW (decl)) | |
1805 | TREE_NOTHROW (call) = 1; | |
1806 | } | |
1807 | ||
1808 | ||
1809 | /* T is CALL_EXPR. Set current_function_calls_* flags. */ | |
1810 | ||
1811 | void | |
1812 | notice_special_calls (tree t) | |
1813 | { | |
1814 | int flags = call_expr_flags (t); | |
1815 | ||
1816 | if (flags & ECF_MAY_BE_ALLOCA) | |
1817 | current_function_calls_alloca = true; | |
1818 | if (flags & ECF_RETURNS_TWICE) | |
1819 | current_function_calls_setjmp = true; | |
1820 | } | |
1821 | ||
1822 | ||
1823 | /* Clear flags set by notice_special_calls. Used by dead code removal | |
1824 | to update the flags. */ | |
1825 | ||
1826 | void | |
1827 | clear_special_calls (void) | |
1828 | { | |
1829 | current_function_calls_alloca = false; | |
1830 | current_function_calls_setjmp = false; | |
1831 | } | |
1832 | ||
1833 | ||
1834 | static void | |
1835 | remove_useless_stmts_1 (tree *tp, struct rus_data *data) | |
1836 | { | |
cd709752 | 1837 | tree t = *tp, op; |
6de9cd9a DN |
1838 | |
1839 | switch (TREE_CODE (t)) | |
1840 | { | |
1841 | case COND_EXPR: | |
1842 | remove_useless_stmts_cond (tp, data); | |
1843 | break; | |
1844 | ||
1845 | case TRY_FINALLY_EXPR: | |
1846 | remove_useless_stmts_tf (tp, data); | |
1847 | break; | |
1848 | ||
1849 | case TRY_CATCH_EXPR: | |
1850 | remove_useless_stmts_tc (tp, data); | |
1851 | break; | |
1852 | ||
1853 | case BIND_EXPR: | |
1854 | remove_useless_stmts_bind (tp, data); | |
1855 | break; | |
1856 | ||
1857 | case GOTO_EXPR: | |
1858 | remove_useless_stmts_goto (tp, data); | |
1859 | break; | |
1860 | ||
1861 | case LABEL_EXPR: | |
1862 | remove_useless_stmts_label (tp, data); | |
1863 | break; | |
1864 | ||
1865 | case RETURN_EXPR: | |
53e782e5 | 1866 | fold_stmt (tp); |
6de9cd9a DN |
1867 | data->last_goto = NULL; |
1868 | data->may_branch = true; | |
1869 | break; | |
1870 | ||
1871 | case CALL_EXPR: | |
53e782e5 | 1872 | fold_stmt (tp); |
6de9cd9a DN |
1873 | data->last_goto = NULL; |
1874 | notice_special_calls (t); | |
1875 | update_call_expr_flags (t); | |
1876 | if (tree_could_throw_p (t)) | |
1877 | data->may_throw = true; | |
1878 | break; | |
1879 | ||
1880 | case MODIFY_EXPR: | |
07beea0d AH |
1881 | gcc_unreachable (); |
1882 | ||
1883 | case GIMPLE_MODIFY_STMT: | |
6de9cd9a | 1884 | data->last_goto = NULL; |
53e782e5 | 1885 | fold_stmt (tp); |
cd709752 RH |
1886 | op = get_call_expr_in (t); |
1887 | if (op) | |
6de9cd9a | 1888 | { |
cd709752 RH |
1889 | update_call_expr_flags (op); |
1890 | notice_special_calls (op); | |
6de9cd9a DN |
1891 | } |
1892 | if (tree_could_throw_p (t)) | |
1893 | data->may_throw = true; | |
1894 | break; | |
1895 | ||
1896 | case STATEMENT_LIST: | |
1897 | { | |
1898 | tree_stmt_iterator i = tsi_start (t); | |
1899 | while (!tsi_end_p (i)) | |
1900 | { | |
1901 | t = tsi_stmt (i); | |
1902 | if (IS_EMPTY_STMT (t)) | |
1903 | { | |
1904 | tsi_delink (&i); | |
1905 | continue; | |
1906 | } | |
6531d1be | 1907 | |
6de9cd9a DN |
1908 | remove_useless_stmts_1 (tsi_stmt_ptr (i), data); |
1909 | ||
1910 | t = tsi_stmt (i); | |
1911 | if (TREE_CODE (t) == STATEMENT_LIST) | |
1912 | { | |
1913 | tsi_link_before (&i, t, TSI_SAME_STMT); | |
1914 | tsi_delink (&i); | |
1915 | } | |
1916 | else | |
1917 | tsi_next (&i); | |
1918 | } | |
1919 | } | |
1920 | break; | |
8e14584d | 1921 | case ASM_EXPR: |
53e782e5 AP |
1922 | fold_stmt (tp); |
1923 | data->last_goto = NULL; | |
1924 | break; | |
6de9cd9a DN |
1925 | |
1926 | default: | |
1927 | data->last_goto = NULL; | |
1928 | break; | |
1929 | } | |
1930 | } | |
1931 | ||
c2924966 | 1932 | static unsigned int |
6de9cd9a DN |
1933 | remove_useless_stmts (void) |
1934 | { | |
1935 | struct rus_data data; | |
1936 | ||
1937 | clear_special_calls (); | |
1938 | ||
1939 | do | |
1940 | { | |
1941 | memset (&data, 0, sizeof (data)); | |
1942 | remove_useless_stmts_1 (&DECL_SAVED_TREE (current_function_decl), &data); | |
1943 | } | |
1944 | while (data.repeat); | |
c2924966 | 1945 | return 0; |
6de9cd9a DN |
1946 | } |
1947 | ||
1948 | ||
6531d1be | 1949 | struct tree_opt_pass pass_remove_useless_stmts = |
6de9cd9a DN |
1950 | { |
1951 | "useless", /* name */ | |
1952 | NULL, /* gate */ | |
1953 | remove_useless_stmts, /* execute */ | |
1954 | NULL, /* sub */ | |
1955 | NULL, /* next */ | |
1956 | 0, /* static_pass_number */ | |
1957 | 0, /* tv_id */ | |
9e5a3e6c RH |
1958 | PROP_gimple_any, /* properties_required */ |
1959 | 0, /* properties_provided */ | |
6de9cd9a DN |
1960 | 0, /* properties_destroyed */ |
1961 | 0, /* todo_flags_start */ | |
9f8628ba PB |
1962 | TODO_dump_func, /* todo_flags_finish */ |
1963 | 0 /* letter */ | |
6de9cd9a DN |
1964 | }; |
1965 | ||
6de9cd9a DN |
1966 | /* Remove PHI nodes associated with basic block BB and all edges out of BB. */ |
1967 | ||
1968 | static void | |
1969 | remove_phi_nodes_and_edges_for_unreachable_block (basic_block bb) | |
1970 | { | |
1971 | tree phi; | |
1972 | ||
1973 | /* Since this block is no longer reachable, we can just delete all | |
1974 | of its PHI nodes. */ | |
1975 | phi = phi_nodes (bb); | |
1976 | while (phi) | |
1977 | { | |
17192884 | 1978 | tree next = PHI_CHAIN (phi); |
9b3b55a1 | 1979 | remove_phi_node (phi, NULL_TREE, true); |
6de9cd9a DN |
1980 | phi = next; |
1981 | } | |
1982 | ||
1983 | /* Remove edges to BB's successors. */ | |
628f6a4e | 1984 | while (EDGE_COUNT (bb->succs) > 0) |
d0d2cc21 | 1985 | remove_edge (EDGE_SUCC (bb, 0)); |
6de9cd9a DN |
1986 | } |
1987 | ||
1988 | ||
1989 | /* Remove statements of basic block BB. */ | |
1990 | ||
1991 | static void | |
1992 | remove_bb (basic_block bb) | |
1993 | { | |
1994 | block_stmt_iterator i; | |
dbce1570 PB |
1995 | #ifdef USE_MAPPED_LOCATION |
1996 | source_location loc = UNKNOWN_LOCATION; | |
1997 | #else | |
9506ac2b | 1998 | source_locus loc = 0; |
dbce1570 | 1999 | #endif |
6de9cd9a DN |
2000 | |
2001 | if (dump_file) | |
2002 | { | |
2003 | fprintf (dump_file, "Removing basic block %d\n", bb->index); | |
2004 | if (dump_flags & TDF_DETAILS) | |
2005 | { | |
2006 | dump_bb (bb, dump_file, 0); | |
2007 | fprintf (dump_file, "\n"); | |
2008 | } | |
2009 | } | |
2010 | ||
2b271002 ZD |
2011 | if (current_loops) |
2012 | { | |
2013 | struct loop *loop = bb->loop_father; | |
2014 | ||
598ec7bd ZD |
2015 | /* If a loop gets removed, clean up the information associated |
2016 | with it. */ | |
2b271002 ZD |
2017 | if (loop->latch == bb |
2018 | || loop->header == bb) | |
598ec7bd | 2019 | free_numbers_of_iterations_estimates_loop (loop); |
2b271002 ZD |
2020 | } |
2021 | ||
6de9cd9a | 2022 | /* Remove all the instructions in the block. */ |
77568960 | 2023 | for (i = bsi_start (bb); !bsi_end_p (i);) |
6de9cd9a DN |
2024 | { |
2025 | tree stmt = bsi_stmt (i); | |
77568960 | 2026 | if (TREE_CODE (stmt) == LABEL_EXPR |
bb1ecfe8 RH |
2027 | && (FORCED_LABEL (LABEL_EXPR_LABEL (stmt)) |
2028 | || DECL_NONLOCAL (LABEL_EXPR_LABEL (stmt)))) | |
77568960 | 2029 | { |
bb1ecfe8 RH |
2030 | basic_block new_bb; |
2031 | block_stmt_iterator new_bsi; | |
2032 | ||
2033 | /* A non-reachable non-local label may still be referenced. | |
2034 | But it no longer needs to carry the extra semantics of | |
2035 | non-locality. */ | |
2036 | if (DECL_NONLOCAL (LABEL_EXPR_LABEL (stmt))) | |
2037 | { | |
2038 | DECL_NONLOCAL (LABEL_EXPR_LABEL (stmt)) = 0; | |
2039 | FORCED_LABEL (LABEL_EXPR_LABEL (stmt)) = 1; | |
2040 | } | |
6531d1be | 2041 | |
bb1ecfe8 RH |
2042 | new_bb = bb->prev_bb; |
2043 | new_bsi = bsi_start (new_bb); | |
736432ee | 2044 | bsi_remove (&i, false); |
ef0b4f28 | 2045 | bsi_insert_before (&new_bsi, stmt, BSI_NEW_STMT); |
77568960 AP |
2046 | } |
2047 | else | |
2048 | { | |
1ff54bfb KH |
2049 | /* Release SSA definitions if we are in SSA. Note that we |
2050 | may be called when not in SSA. For example, | |
2051 | final_cleanup calls this function via | |
2052 | cleanup_tree_cfg. */ | |
5cd4ec7f | 2053 | if (gimple_in_ssa_p (cfun)) |
1ff54bfb | 2054 | release_defs (stmt); |
6de9cd9a | 2055 | |
736432ee | 2056 | bsi_remove (&i, true); |
77568960 | 2057 | } |
6de9cd9a DN |
2058 | |
2059 | /* Don't warn for removed gotos. Gotos are often removed due to | |
2060 | jump threading, thus resulting in bogus warnings. Not great, | |
2061 | since this way we lose warnings for gotos in the original | |
2062 | program that are indeed unreachable. */ | |
9506ac2b | 2063 | if (TREE_CODE (stmt) != GOTO_EXPR && EXPR_HAS_LOCATION (stmt) && !loc) |
43e05e45 | 2064 | { |
9506ac2b | 2065 | #ifdef USE_MAPPED_LOCATION |
dbce1570 PB |
2066 | if (EXPR_HAS_LOCATION (stmt)) |
2067 | loc = EXPR_LOCATION (stmt); | |
9506ac2b | 2068 | #else |
dbce1570 | 2069 | source_locus t; |
43e05e45 | 2070 | t = EXPR_LOCUS (stmt); |
43e05e45 SB |
2071 | if (t && LOCATION_LINE (*t) > 0) |
2072 | loc = t; | |
dbce1570 | 2073 | #endif |
43e05e45 | 2074 | } |
6de9cd9a DN |
2075 | } |
2076 | ||
2077 | /* If requested, give a warning that the first statement in the | |
2078 | block is unreachable. We walk statements backwards in the | |
2079 | loop above, so the last statement we process is the first statement | |
2080 | in the block. */ | |
9506ac2b | 2081 | #ifdef USE_MAPPED_LOCATION |
44c21c7f DD |
2082 | if (loc > BUILTINS_LOCATION) |
2083 | warning (OPT_Wunreachable_code, "%Hwill never be executed", &loc); | |
9506ac2b | 2084 | #else |
44c21c7f DD |
2085 | if (loc) |
2086 | warning (OPT_Wunreachable_code, "%Hwill never be executed", loc); | |
9506ac2b | 2087 | #endif |
6de9cd9a DN |
2088 | |
2089 | remove_phi_nodes_and_edges_for_unreachable_block (bb); | |
2090 | } | |
2091 | ||
6de9cd9a | 2092 | |
35920270 KH |
2093 | /* Given a basic block BB ending with COND_EXPR or SWITCH_EXPR, and a |
2094 | predicate VAL, return the edge that will be taken out of the block. | |
2095 | If VAL does not match a unique edge, NULL is returned. */ | |
6de9cd9a DN |
2096 | |
2097 | edge | |
2098 | find_taken_edge (basic_block bb, tree val) | |
2099 | { | |
2100 | tree stmt; | |
2101 | ||
2102 | stmt = last_stmt (bb); | |
2103 | ||
1e128c5f GB |
2104 | gcc_assert (stmt); |
2105 | gcc_assert (is_ctrl_stmt (stmt)); | |
65f4323d | 2106 | gcc_assert (val); |
6de9cd9a | 2107 | |
be477406 | 2108 | if (! is_gimple_min_invariant (val)) |
6de9cd9a DN |
2109 | return NULL; |
2110 | ||
2111 | if (TREE_CODE (stmt) == COND_EXPR) | |
2112 | return find_taken_edge_cond_expr (bb, val); | |
2113 | ||
2114 | if (TREE_CODE (stmt) == SWITCH_EXPR) | |
2115 | return find_taken_edge_switch_expr (bb, val); | |
2116 | ||
be477406 JL |
2117 | if (computed_goto_p (stmt)) |
2118 | return find_taken_edge_computed_goto (bb, TREE_OPERAND( val, 0)); | |
2119 | ||
35920270 | 2120 | gcc_unreachable (); |
6de9cd9a DN |
2121 | } |
2122 | ||
be477406 JL |
2123 | /* Given a constant value VAL and the entry block BB to a GOTO_EXPR |
2124 | statement, determine which of the outgoing edges will be taken out of the | |
2125 | block. Return NULL if either edge may be taken. */ | |
2126 | ||
2127 | static edge | |
2128 | find_taken_edge_computed_goto (basic_block bb, tree val) | |
2129 | { | |
2130 | basic_block dest; | |
2131 | edge e = NULL; | |
2132 | ||
2133 | dest = label_to_block (val); | |
2134 | if (dest) | |
2135 | { | |
2136 | e = find_edge (bb, dest); | |
2137 | gcc_assert (e != NULL); | |
2138 | } | |
2139 | ||
2140 | return e; | |
2141 | } | |
6de9cd9a DN |
2142 | |
2143 | /* Given a constant value VAL and the entry block BB to a COND_EXPR | |
2144 | statement, determine which of the two edges will be taken out of the | |
2145 | block. Return NULL if either edge may be taken. */ | |
2146 | ||
2147 | static edge | |
2148 | find_taken_edge_cond_expr (basic_block bb, tree val) | |
2149 | { | |
2150 | edge true_edge, false_edge; | |
2151 | ||
2152 | extract_true_false_edges_from_block (bb, &true_edge, &false_edge); | |
6531d1be | 2153 | |
f1b19062 ZD |
2154 | gcc_assert (TREE_CODE (val) == INTEGER_CST); |
2155 | return (zero_p (val) ? false_edge : true_edge); | |
6de9cd9a DN |
2156 | } |
2157 | ||
fca01525 | 2158 | /* Given an INTEGER_CST VAL and the entry block BB to a SWITCH_EXPR |
6de9cd9a DN |
2159 | statement, determine which edge will be taken out of the block. Return |
2160 | NULL if any edge may be taken. */ | |
2161 | ||
2162 | static edge | |
2163 | find_taken_edge_switch_expr (basic_block bb, tree val) | |
2164 | { | |
2165 | tree switch_expr, taken_case; | |
2166 | basic_block dest_bb; | |
2167 | edge e; | |
2168 | ||
6de9cd9a DN |
2169 | switch_expr = last_stmt (bb); |
2170 | taken_case = find_case_label_for_value (switch_expr, val); | |
2171 | dest_bb = label_to_block (CASE_LABEL (taken_case)); | |
2172 | ||
2173 | e = find_edge (bb, dest_bb); | |
1e128c5f | 2174 | gcc_assert (e); |
6de9cd9a DN |
2175 | return e; |
2176 | } | |
2177 | ||
2178 | ||
f667741c SB |
2179 | /* Return the CASE_LABEL_EXPR that SWITCH_EXPR will take for VAL. |
2180 | We can make optimal use here of the fact that the case labels are | |
2181 | sorted: We can do a binary search for a case matching VAL. */ | |
6de9cd9a DN |
2182 | |
2183 | static tree | |
2184 | find_case_label_for_value (tree switch_expr, tree val) | |
2185 | { | |
2186 | tree vec = SWITCH_LABELS (switch_expr); | |
f667741c SB |
2187 | size_t low, high, n = TREE_VEC_LENGTH (vec); |
2188 | tree default_case = TREE_VEC_ELT (vec, n - 1); | |
6de9cd9a | 2189 | |
f667741c | 2190 | for (low = -1, high = n - 1; high - low > 1; ) |
6de9cd9a | 2191 | { |
f667741c | 2192 | size_t i = (high + low) / 2; |
6de9cd9a | 2193 | tree t = TREE_VEC_ELT (vec, i); |
f667741c SB |
2194 | int cmp; |
2195 | ||
2196 | /* Cache the result of comparing CASE_LOW and val. */ | |
2197 | cmp = tree_int_cst_compare (CASE_LOW (t), val); | |
6de9cd9a | 2198 | |
f667741c SB |
2199 | if (cmp > 0) |
2200 | high = i; | |
2201 | else | |
2202 | low = i; | |
2203 | ||
2204 | if (CASE_HIGH (t) == NULL) | |
6de9cd9a | 2205 | { |
f667741c SB |
2206 | /* A singe-valued case label. */ |
2207 | if (cmp == 0) | |
6de9cd9a DN |
2208 | return t; |
2209 | } | |
2210 | else | |
2211 | { | |
2212 | /* A case range. We can only handle integer ranges. */ | |
f667741c | 2213 | if (cmp <= 0 && tree_int_cst_compare (CASE_HIGH (t), val) >= 0) |
6de9cd9a DN |
2214 | return t; |
2215 | } | |
2216 | } | |
2217 | ||
6de9cd9a DN |
2218 | return default_case; |
2219 | } | |
2220 | ||
2221 | ||
6de9cd9a DN |
2222 | |
2223 | ||
6de9cd9a DN |
2224 | /*--------------------------------------------------------------------------- |
2225 | Debugging functions | |
2226 | ---------------------------------------------------------------------------*/ | |
2227 | ||
2228 | /* Dump tree-specific information of block BB to file OUTF. */ | |
2229 | ||
2230 | void | |
2231 | tree_dump_bb (basic_block bb, FILE *outf, int indent) | |
2232 | { | |
38635499 | 2233 | dump_generic_bb (outf, bb, indent, TDF_VOPS|TDF_MEMSYMS); |
6de9cd9a DN |
2234 | } |
2235 | ||
2236 | ||
2237 | /* Dump a basic block on stderr. */ | |
2238 | ||
2239 | void | |
2240 | debug_tree_bb (basic_block bb) | |
2241 | { | |
2242 | dump_bb (bb, stderr, 0); | |
2243 | } | |
2244 | ||
2245 | ||
2246 | /* Dump basic block with index N on stderr. */ | |
2247 | ||
2248 | basic_block | |
2249 | debug_tree_bb_n (int n) | |
2250 | { | |
2251 | debug_tree_bb (BASIC_BLOCK (n)); | |
2252 | return BASIC_BLOCK (n); | |
6531d1be | 2253 | } |
6de9cd9a DN |
2254 | |
2255 | ||
2256 | /* Dump the CFG on stderr. | |
2257 | ||
2258 | FLAGS are the same used by the tree dumping functions | |
6531d1be | 2259 | (see TDF_* in tree-pass.h). */ |
6de9cd9a DN |
2260 | |
2261 | void | |
2262 | debug_tree_cfg (int flags) | |
2263 | { | |
2264 | dump_tree_cfg (stderr, flags); | |
2265 | } | |
2266 | ||
2267 | ||
2268 | /* Dump the program showing basic block boundaries on the given FILE. | |
2269 | ||
2270 | FLAGS are the same used by the tree dumping functions (see TDF_* in | |
2271 | tree.h). */ | |
2272 | ||
2273 | void | |
2274 | dump_tree_cfg (FILE *file, int flags) | |
2275 | { | |
2276 | if (flags & TDF_DETAILS) | |
2277 | { | |
2278 | const char *funcname | |
673fda6b | 2279 | = lang_hooks.decl_printable_name (current_function_decl, 2); |
6de9cd9a DN |
2280 | |
2281 | fputc ('\n', file); | |
2282 | fprintf (file, ";; Function %s\n\n", funcname); | |
2283 | fprintf (file, ";; \n%d basic blocks, %d edges, last basic block %d.\n\n", | |
2284 | n_basic_blocks, n_edges, last_basic_block); | |
2285 | ||
2286 | brief_dump_cfg (file); | |
2287 | fprintf (file, "\n"); | |
2288 | } | |
2289 | ||
2290 | if (flags & TDF_STATS) | |
2291 | dump_cfg_stats (file); | |
2292 | ||
2293 | dump_function_to_file (current_function_decl, file, flags | TDF_BLOCKS); | |
2294 | } | |
2295 | ||
2296 | ||
2297 | /* Dump CFG statistics on FILE. */ | |
2298 | ||
2299 | void | |
2300 | dump_cfg_stats (FILE *file) | |
2301 | { | |
2302 | static long max_num_merged_labels = 0; | |
2303 | unsigned long size, total = 0; | |
7b0cab99 | 2304 | long num_edges; |
6de9cd9a DN |
2305 | basic_block bb; |
2306 | const char * const fmt_str = "%-30s%-13s%12s\n"; | |
f7fda749 | 2307 | const char * const fmt_str_1 = "%-30s%13d%11lu%c\n"; |
cac50d94 | 2308 | const char * const fmt_str_2 = "%-30s%13ld%11lu%c\n"; |
6de9cd9a DN |
2309 | const char * const fmt_str_3 = "%-43s%11lu%c\n"; |
2310 | const char *funcname | |
673fda6b | 2311 | = lang_hooks.decl_printable_name (current_function_decl, 2); |
6de9cd9a DN |
2312 | |
2313 | ||
2314 | fprintf (file, "\nCFG Statistics for %s\n\n", funcname); | |
2315 | ||
2316 | fprintf (file, "---------------------------------------------------------\n"); | |
2317 | fprintf (file, fmt_str, "", " Number of ", "Memory"); | |
2318 | fprintf (file, fmt_str, "", " instances ", "used "); | |
2319 | fprintf (file, "---------------------------------------------------------\n"); | |
2320 | ||
2321 | size = n_basic_blocks * sizeof (struct basic_block_def); | |
2322 | total += size; | |
f7fda749 RH |
2323 | fprintf (file, fmt_str_1, "Basic blocks", n_basic_blocks, |
2324 | SCALE (size), LABEL (size)); | |
6de9cd9a | 2325 | |
7b0cab99 | 2326 | num_edges = 0; |
6de9cd9a | 2327 | FOR_EACH_BB (bb) |
7b0cab99 JH |
2328 | num_edges += EDGE_COUNT (bb->succs); |
2329 | size = num_edges * sizeof (struct edge_def); | |
6de9cd9a | 2330 | total += size; |
cac50d94 | 2331 | fprintf (file, fmt_str_2, "Edges", num_edges, SCALE (size), LABEL (size)); |
6de9cd9a | 2332 | |
6de9cd9a DN |
2333 | fprintf (file, "---------------------------------------------------------\n"); |
2334 | fprintf (file, fmt_str_3, "Total memory used by CFG data", SCALE (total), | |
2335 | LABEL (total)); | |
2336 | fprintf (file, "---------------------------------------------------------\n"); | |
2337 | fprintf (file, "\n"); | |
2338 | ||
2339 | if (cfg_stats.num_merged_labels > max_num_merged_labels) | |
2340 | max_num_merged_labels = cfg_stats.num_merged_labels; | |
2341 | ||
2342 | fprintf (file, "Coalesced label blocks: %ld (Max so far: %ld)\n", | |
2343 | cfg_stats.num_merged_labels, max_num_merged_labels); | |
2344 | ||
2345 | fprintf (file, "\n"); | |
2346 | } | |
2347 | ||
2348 | ||
2349 | /* Dump CFG statistics on stderr. Keep extern so that it's always | |
2350 | linked in the final executable. */ | |
2351 | ||
2352 | void | |
2353 | debug_cfg_stats (void) | |
2354 | { | |
2355 | dump_cfg_stats (stderr); | |
2356 | } | |
2357 | ||
2358 | ||
2359 | /* Dump the flowgraph to a .vcg FILE. */ | |
2360 | ||
2361 | static void | |
2362 | tree_cfg2vcg (FILE *file) | |
2363 | { | |
2364 | edge e; | |
628f6a4e | 2365 | edge_iterator ei; |
6de9cd9a DN |
2366 | basic_block bb; |
2367 | const char *funcname | |
673fda6b | 2368 | = lang_hooks.decl_printable_name (current_function_decl, 2); |
6de9cd9a DN |
2369 | |
2370 | /* Write the file header. */ | |
2371 | fprintf (file, "graph: { title: \"%s\"\n", funcname); | |
2372 | fprintf (file, "node: { title: \"ENTRY\" label: \"ENTRY\" }\n"); | |
2373 | fprintf (file, "node: { title: \"EXIT\" label: \"EXIT\" }\n"); | |
2374 | ||
2375 | /* Write blocks and edges. */ | |
628f6a4e | 2376 | FOR_EACH_EDGE (e, ei, ENTRY_BLOCK_PTR->succs) |
6de9cd9a DN |
2377 | { |
2378 | fprintf (file, "edge: { sourcename: \"ENTRY\" targetname: \"%d\"", | |
2379 | e->dest->index); | |
2380 | ||
2381 | if (e->flags & EDGE_FAKE) | |
2382 | fprintf (file, " linestyle: dotted priority: 10"); | |
2383 | else | |
2384 | fprintf (file, " linestyle: solid priority: 100"); | |
2385 | ||
2386 | fprintf (file, " }\n"); | |
2387 | } | |
2388 | fputc ('\n', file); | |
2389 | ||
2390 | FOR_EACH_BB (bb) | |
2391 | { | |
2392 | enum tree_code head_code, end_code; | |
2393 | const char *head_name, *end_name; | |
2394 | int head_line = 0; | |
2395 | int end_line = 0; | |
2396 | tree first = first_stmt (bb); | |
2397 | tree last = last_stmt (bb); | |
2398 | ||
2399 | if (first) | |
2400 | { | |
2401 | head_code = TREE_CODE (first); | |
2402 | head_name = tree_code_name[head_code]; | |
2403 | head_line = get_lineno (first); | |
2404 | } | |
2405 | else | |
2406 | head_name = "no-statement"; | |
2407 | ||
2408 | if (last) | |
2409 | { | |
2410 | end_code = TREE_CODE (last); | |
2411 | end_name = tree_code_name[end_code]; | |
2412 | end_line = get_lineno (last); | |
2413 | } | |
2414 | else | |
2415 | end_name = "no-statement"; | |
2416 | ||
2417 | fprintf (file, "node: { title: \"%d\" label: \"#%d\\n%s (%d)\\n%s (%d)\"}\n", | |
2418 | bb->index, bb->index, head_name, head_line, end_name, | |
2419 | end_line); | |
2420 | ||
628f6a4e | 2421 | FOR_EACH_EDGE (e, ei, bb->succs) |
6de9cd9a DN |
2422 | { |
2423 | if (e->dest == EXIT_BLOCK_PTR) | |
2424 | fprintf (file, "edge: { sourcename: \"%d\" targetname: \"EXIT\"", bb->index); | |
2425 | else | |
2426 | fprintf (file, "edge: { sourcename: \"%d\" targetname: \"%d\"", bb->index, e->dest->index); | |
2427 | ||
2428 | if (e->flags & EDGE_FAKE) | |
2429 | fprintf (file, " priority: 10 linestyle: dotted"); | |
2430 | else | |
2431 | fprintf (file, " priority: 100 linestyle: solid"); | |
2432 | ||
2433 | fprintf (file, " }\n"); | |
2434 | } | |
2435 | ||
2436 | if (bb->next_bb != EXIT_BLOCK_PTR) | |
2437 | fputc ('\n', file); | |
2438 | } | |
2439 | ||
2440 | fputs ("}\n\n", file); | |
2441 | } | |
2442 | ||
2443 | ||
2444 | ||
2445 | /*--------------------------------------------------------------------------- | |
2446 | Miscellaneous helpers | |
2447 | ---------------------------------------------------------------------------*/ | |
2448 | ||
2449 | /* Return true if T represents a stmt that always transfers control. */ | |
2450 | ||
2451 | bool | |
2452 | is_ctrl_stmt (tree t) | |
2453 | { | |
2454 | return (TREE_CODE (t) == COND_EXPR | |
2455 | || TREE_CODE (t) == SWITCH_EXPR | |
2456 | || TREE_CODE (t) == GOTO_EXPR | |
2457 | || TREE_CODE (t) == RETURN_EXPR | |
2458 | || TREE_CODE (t) == RESX_EXPR); | |
2459 | } | |
2460 | ||
2461 | ||
2462 | /* Return true if T is a statement that may alter the flow of control | |
2463 | (e.g., a call to a non-returning function). */ | |
2464 | ||
2465 | bool | |
2466 | is_ctrl_altering_stmt (tree t) | |
2467 | { | |
cd709752 | 2468 | tree call; |
6de9cd9a | 2469 | |
1e128c5f | 2470 | gcc_assert (t); |
cd709752 RH |
2471 | call = get_call_expr_in (t); |
2472 | if (call) | |
6de9cd9a | 2473 | { |
6de9cd9a DN |
2474 | /* A non-pure/const CALL_EXPR alters flow control if the current |
2475 | function has nonlocal labels. */ | |
cd709752 | 2476 | if (TREE_SIDE_EFFECTS (call) && current_function_has_nonlocal_label) |
6de9cd9a DN |
2477 | return true; |
2478 | ||
2479 | /* A CALL_EXPR also alters control flow if it does not return. */ | |
6e14af16 | 2480 | if (call_expr_flags (call) & ECF_NORETURN) |
6de9cd9a | 2481 | return true; |
6de9cd9a DN |
2482 | } |
2483 | ||
50674e96 | 2484 | /* OpenMP directives alter control flow. */ |
bed575d5 | 2485 | if (OMP_DIRECTIVE_P (t)) |
50674e96 DN |
2486 | return true; |
2487 | ||
6de9cd9a DN |
2488 | /* If a statement can throw, it alters control flow. */ |
2489 | return tree_can_throw_internal (t); | |
2490 | } | |
2491 | ||
2492 | ||
2493 | /* Return true if T is a computed goto. */ | |
2494 | ||
2495 | bool | |
2496 | computed_goto_p (tree t) | |
2497 | { | |
2498 | return (TREE_CODE (t) == GOTO_EXPR | |
2499 | && TREE_CODE (GOTO_DESTINATION (t)) != LABEL_DECL); | |
2500 | } | |
2501 | ||
2502 | ||
4f6c2131 | 2503 | /* Return true if T is a simple local goto. */ |
6de9cd9a DN |
2504 | |
2505 | bool | |
4f6c2131 | 2506 | simple_goto_p (tree t) |
6de9cd9a | 2507 | { |
4f6c2131 EB |
2508 | return (TREE_CODE (t) == GOTO_EXPR |
2509 | && TREE_CODE (GOTO_DESTINATION (t)) == LABEL_DECL); | |
2510 | } | |
2511 | ||
2512 | ||
2513 | /* Return true if T can make an abnormal transfer of control flow. | |
2514 | Transfers of control flow associated with EH are excluded. */ | |
2515 | ||
2516 | bool | |
2517 | tree_can_make_abnormal_goto (tree t) | |
2518 | { | |
2519 | if (computed_goto_p (t)) | |
2520 | return true; | |
07beea0d AH |
2521 | if (TREE_CODE (t) == GIMPLE_MODIFY_STMT) |
2522 | t = GIMPLE_STMT_OPERAND (t, 1); | |
4f6c2131 EB |
2523 | if (TREE_CODE (t) == WITH_SIZE_EXPR) |
2524 | t = TREE_OPERAND (t, 0); | |
2525 | if (TREE_CODE (t) == CALL_EXPR) | |
2526 | return TREE_SIDE_EFFECTS (t) && current_function_has_nonlocal_label; | |
2527 | return false; | |
6de9cd9a DN |
2528 | } |
2529 | ||
2530 | ||
2531 | /* Return true if T should start a new basic block. PREV_T is the | |
2532 | statement preceding T. It is used when T is a label or a case label. | |
2533 | Labels should only start a new basic block if their previous statement | |
2534 | wasn't a label. Otherwise, sequence of labels would generate | |
2535 | unnecessary basic blocks that only contain a single label. */ | |
2536 | ||
2537 | static inline bool | |
2538 | stmt_starts_bb_p (tree t, tree prev_t) | |
2539 | { | |
6de9cd9a DN |
2540 | if (t == NULL_TREE) |
2541 | return false; | |
2542 | ||
2543 | /* LABEL_EXPRs start a new basic block only if the preceding | |
2544 | statement wasn't a label of the same type. This prevents the | |
2545 | creation of consecutive blocks that have nothing but a single | |
2546 | label. */ | |
229cc11f | 2547 | if (TREE_CODE (t) == LABEL_EXPR) |
6de9cd9a DN |
2548 | { |
2549 | /* Nonlocal and computed GOTO targets always start a new block. */ | |
229cc11f KH |
2550 | if (DECL_NONLOCAL (LABEL_EXPR_LABEL (t)) |
2551 | || FORCED_LABEL (LABEL_EXPR_LABEL (t))) | |
6de9cd9a DN |
2552 | return true; |
2553 | ||
229cc11f | 2554 | if (prev_t && TREE_CODE (prev_t) == LABEL_EXPR) |
6de9cd9a DN |
2555 | { |
2556 | if (DECL_NONLOCAL (LABEL_EXPR_LABEL (prev_t))) | |
2557 | return true; | |
2558 | ||
2559 | cfg_stats.num_merged_labels++; | |
2560 | return false; | |
2561 | } | |
2562 | else | |
2563 | return true; | |
2564 | } | |
2565 | ||
2566 | return false; | |
2567 | } | |
2568 | ||
2569 | ||
2570 | /* Return true if T should end a basic block. */ | |
2571 | ||
2572 | bool | |
2573 | stmt_ends_bb_p (tree t) | |
2574 | { | |
2575 | return is_ctrl_stmt (t) || is_ctrl_altering_stmt (t); | |
2576 | } | |
2577 | ||
2578 | ||
2579 | /* Add gotos that used to be represented implicitly in the CFG. */ | |
2580 | ||
2581 | void | |
2582 | disband_implicit_edges (void) | |
2583 | { | |
2584 | basic_block bb; | |
2585 | block_stmt_iterator last; | |
2586 | edge e; | |
628f6a4e | 2587 | edge_iterator ei; |
eb4e1c01 | 2588 | tree stmt, label; |
6de9cd9a DN |
2589 | |
2590 | FOR_EACH_BB (bb) | |
2591 | { | |
2592 | last = bsi_last (bb); | |
2593 | stmt = last_stmt (bb); | |
2594 | ||
2595 | if (stmt && TREE_CODE (stmt) == COND_EXPR) | |
2596 | { | |
2597 | /* Remove superfluous gotos from COND_EXPR branches. Moved | |
2598 | from cfg_remove_useless_stmts here since it violates the | |
2599 | invariants for tree--cfg correspondence and thus fits better | |
2600 | here where we do it anyway. */ | |
9ff3d2de JL |
2601 | e = find_edge (bb, bb->next_bb); |
2602 | if (e) | |
6de9cd9a | 2603 | { |
6de9cd9a DN |
2604 | if (e->flags & EDGE_TRUE_VALUE) |
2605 | COND_EXPR_THEN (stmt) = build_empty_stmt (); | |
2606 | else if (e->flags & EDGE_FALSE_VALUE) | |
2607 | COND_EXPR_ELSE (stmt) = build_empty_stmt (); | |
2608 | else | |
1e128c5f | 2609 | gcc_unreachable (); |
6de9cd9a DN |
2610 | e->flags |= EDGE_FALLTHRU; |
2611 | } | |
2612 | ||
2613 | continue; | |
2614 | } | |
2615 | ||
2616 | if (stmt && TREE_CODE (stmt) == RETURN_EXPR) | |
2617 | { | |
2618 | /* Remove the RETURN_EXPR if we may fall though to the exit | |
2619 | instead. */ | |
c5cbcccf ZD |
2620 | gcc_assert (single_succ_p (bb)); |
2621 | gcc_assert (single_succ (bb) == EXIT_BLOCK_PTR); | |
6de9cd9a DN |
2622 | |
2623 | if (bb->next_bb == EXIT_BLOCK_PTR | |
2624 | && !TREE_OPERAND (stmt, 0)) | |
2625 | { | |
736432ee | 2626 | bsi_remove (&last, true); |
c5cbcccf | 2627 | single_succ_edge (bb)->flags |= EDGE_FALLTHRU; |
6de9cd9a DN |
2628 | } |
2629 | continue; | |
2630 | } | |
2631 | ||
2632 | /* There can be no fallthru edge if the last statement is a control | |
2633 | one. */ | |
2634 | if (stmt && is_ctrl_stmt (stmt)) | |
2635 | continue; | |
2636 | ||
2637 | /* Find a fallthru edge and emit the goto if necessary. */ | |
628f6a4e | 2638 | FOR_EACH_EDGE (e, ei, bb->succs) |
6de9cd9a DN |
2639 | if (e->flags & EDGE_FALLTHRU) |
2640 | break; | |
2641 | ||
62b857ea | 2642 | if (!e || e->dest == bb->next_bb) |
6de9cd9a DN |
2643 | continue; |
2644 | ||
1e128c5f | 2645 | gcc_assert (e->dest != EXIT_BLOCK_PTR); |
6de9cd9a DN |
2646 | label = tree_block_label (e->dest); |
2647 | ||
62b857ea | 2648 | stmt = build1 (GOTO_EXPR, void_type_node, label); |
9506ac2b PB |
2649 | #ifdef USE_MAPPED_LOCATION |
2650 | SET_EXPR_LOCATION (stmt, e->goto_locus); | |
2651 | #else | |
62b857ea | 2652 | SET_EXPR_LOCUS (stmt, e->goto_locus); |
9506ac2b | 2653 | #endif |
62b857ea | 2654 | bsi_insert_after (&last, stmt, BSI_NEW_STMT); |
6de9cd9a DN |
2655 | e->flags &= ~EDGE_FALLTHRU; |
2656 | } | |
2657 | } | |
2658 | ||
242229bb | 2659 | /* Remove block annotations and other datastructures. */ |
6de9cd9a DN |
2660 | |
2661 | void | |
242229bb | 2662 | delete_tree_cfg_annotations (void) |
6de9cd9a | 2663 | { |
6de9cd9a | 2664 | label_to_block_map = NULL; |
6de9cd9a DN |
2665 | } |
2666 | ||
2667 | ||
2668 | /* Return the first statement in basic block BB. */ | |
2669 | ||
2670 | tree | |
2671 | first_stmt (basic_block bb) | |
2672 | { | |
2673 | block_stmt_iterator i = bsi_start (bb); | |
2674 | return !bsi_end_p (i) ? bsi_stmt (i) : NULL_TREE; | |
2675 | } | |
2676 | ||
2677 | ||
2678 | /* Return the last statement in basic block BB. */ | |
2679 | ||
2680 | tree | |
2681 | last_stmt (basic_block bb) | |
2682 | { | |
2683 | block_stmt_iterator b = bsi_last (bb); | |
2684 | return !bsi_end_p (b) ? bsi_stmt (b) : NULL_TREE; | |
2685 | } | |
2686 | ||
2687 | ||
2688 | /* Return a pointer to the last statement in block BB. */ | |
2689 | ||
2690 | tree * | |
2691 | last_stmt_ptr (basic_block bb) | |
2692 | { | |
2693 | block_stmt_iterator last = bsi_last (bb); | |
2694 | return !bsi_end_p (last) ? bsi_stmt_ptr (last) : NULL; | |
2695 | } | |
2696 | ||
2697 | ||
2698 | /* Return the last statement of an otherwise empty block. Return NULL | |
2699 | if the block is totally empty, or if it contains more than one | |
2700 | statement. */ | |
2701 | ||
2702 | tree | |
2703 | last_and_only_stmt (basic_block bb) | |
2704 | { | |
2705 | block_stmt_iterator i = bsi_last (bb); | |
2706 | tree last, prev; | |
2707 | ||
2708 | if (bsi_end_p (i)) | |
2709 | return NULL_TREE; | |
2710 | ||
2711 | last = bsi_stmt (i); | |
2712 | bsi_prev (&i); | |
2713 | if (bsi_end_p (i)) | |
2714 | return last; | |
2715 | ||
2716 | /* Empty statements should no longer appear in the instruction stream. | |
2717 | Everything that might have appeared before should be deleted by | |
2718 | remove_useless_stmts, and the optimizers should just bsi_remove | |
2719 | instead of smashing with build_empty_stmt. | |
2720 | ||
2721 | Thus the only thing that should appear here in a block containing | |
2722 | one executable statement is a label. */ | |
2723 | prev = bsi_stmt (i); | |
2724 | if (TREE_CODE (prev) == LABEL_EXPR) | |
2725 | return last; | |
2726 | else | |
2727 | return NULL_TREE; | |
2728 | } | |
2729 | ||
2730 | ||
2731 | /* Mark BB as the basic block holding statement T. */ | |
2732 | ||
2733 | void | |
2734 | set_bb_for_stmt (tree t, basic_block bb) | |
2735 | { | |
30d396e3 ZD |
2736 | if (TREE_CODE (t) == PHI_NODE) |
2737 | PHI_BB (t) = bb; | |
2738 | else if (TREE_CODE (t) == STATEMENT_LIST) | |
6de9cd9a DN |
2739 | { |
2740 | tree_stmt_iterator i; | |
2741 | for (i = tsi_start (t); !tsi_end_p (i); tsi_next (&i)) | |
2742 | set_bb_for_stmt (tsi_stmt (i), bb); | |
2743 | } | |
2744 | else | |
2745 | { | |
2746 | stmt_ann_t ann = get_stmt_ann (t); | |
2747 | ann->bb = bb; | |
2748 | ||
50674e96 DN |
2749 | /* If the statement is a label, add the label to block-to-labels map |
2750 | so that we can speed up edge creation for GOTO_EXPRs. */ | |
2751 | if (TREE_CODE (t) == LABEL_EXPR) | |
6de9cd9a DN |
2752 | { |
2753 | int uid; | |
2754 | ||
2755 | t = LABEL_EXPR_LABEL (t); | |
2756 | uid = LABEL_DECL_UID (t); | |
2757 | if (uid == -1) | |
2758 | { | |
e597f337 | 2759 | unsigned old_len = VEC_length (basic_block, label_to_block_map); |
6de9cd9a | 2760 | LABEL_DECL_UID (t) = uid = cfun->last_label_uid++; |
e597f337 KH |
2761 | if (old_len <= (unsigned) uid) |
2762 | { | |
2763 | basic_block *addr; | |
2764 | unsigned new_len = 3 * uid / 2; | |
2765 | ||
2766 | VEC_safe_grow (basic_block, gc, label_to_block_map, | |
2767 | new_len); | |
2768 | addr = VEC_address (basic_block, label_to_block_map); | |
2769 | memset (&addr[old_len], | |
2770 | 0, sizeof (basic_block) * (new_len - old_len)); | |
2771 | } | |
6de9cd9a DN |
2772 | } |
2773 | else | |
1e128c5f GB |
2774 | /* We're moving an existing label. Make sure that we've |
2775 | removed it from the old block. */ | |
e597f337 KH |
2776 | gcc_assert (!bb |
2777 | || !VEC_index (basic_block, label_to_block_map, uid)); | |
2778 | VEC_replace (basic_block, label_to_block_map, uid, bb); | |
6de9cd9a DN |
2779 | } |
2780 | } | |
2781 | } | |
2782 | ||
0a4fe58f JH |
2783 | /* Faster version of set_bb_for_stmt that assume that statement is being moved |
2784 | from one basic block to another. | |
2785 | For BB splitting we can run into quadratic case, so performance is quite | |
de1e45c3 | 2786 | important and knowing that the tables are big enough, change_bb_for_stmt |
0a4fe58f JH |
2787 | can inline as leaf function. */ |
2788 | static inline void | |
2789 | change_bb_for_stmt (tree t, basic_block bb) | |
2790 | { | |
2791 | get_stmt_ann (t)->bb = bb; | |
2792 | if (TREE_CODE (t) == LABEL_EXPR) | |
2793 | VEC_replace (basic_block, label_to_block_map, | |
2794 | LABEL_DECL_UID (LABEL_EXPR_LABEL (t)), bb); | |
2795 | } | |
2796 | ||
8b11a64c ZD |
2797 | /* Finds iterator for STMT. */ |
2798 | ||
2799 | extern block_stmt_iterator | |
1a1804c2 | 2800 | bsi_for_stmt (tree stmt) |
8b11a64c ZD |
2801 | { |
2802 | block_stmt_iterator bsi; | |
2803 | ||
2804 | for (bsi = bsi_start (bb_for_stmt (stmt)); !bsi_end_p (bsi); bsi_next (&bsi)) | |
2805 | if (bsi_stmt (bsi) == stmt) | |
2806 | return bsi; | |
2807 | ||
1e128c5f | 2808 | gcc_unreachable (); |
8b11a64c | 2809 | } |
6de9cd9a | 2810 | |
f430bae8 AM |
2811 | /* Mark statement T as modified, and update it. */ |
2812 | static inline void | |
2813 | update_modified_stmts (tree t) | |
2814 | { | |
2815 | if (TREE_CODE (t) == STATEMENT_LIST) | |
2816 | { | |
2817 | tree_stmt_iterator i; | |
2818 | tree stmt; | |
2819 | for (i = tsi_start (t); !tsi_end_p (i); tsi_next (&i)) | |
2820 | { | |
2821 | stmt = tsi_stmt (i); | |
2822 | update_stmt_if_modified (stmt); | |
2823 | } | |
2824 | } | |
2825 | else | |
2826 | update_stmt_if_modified (t); | |
2827 | } | |
2828 | ||
6de9cd9a DN |
2829 | /* Insert statement (or statement list) T before the statement |
2830 | pointed-to by iterator I. M specifies how to update iterator I | |
2831 | after insertion (see enum bsi_iterator_update). */ | |
2832 | ||
2833 | void | |
2834 | bsi_insert_before (block_stmt_iterator *i, tree t, enum bsi_iterator_update m) | |
2835 | { | |
2836 | set_bb_for_stmt (t, i->bb); | |
f430bae8 | 2837 | update_modified_stmts (t); |
6de9cd9a DN |
2838 | tsi_link_before (&i->tsi, t, m); |
2839 | } | |
2840 | ||
2841 | ||
2842 | /* Insert statement (or statement list) T after the statement | |
2843 | pointed-to by iterator I. M specifies how to update iterator I | |
2844 | after insertion (see enum bsi_iterator_update). */ | |
2845 | ||
2846 | void | |
2847 | bsi_insert_after (block_stmt_iterator *i, tree t, enum bsi_iterator_update m) | |
2848 | { | |
2849 | set_bb_for_stmt (t, i->bb); | |
f430bae8 | 2850 | update_modified_stmts (t); |
6de9cd9a DN |
2851 | tsi_link_after (&i->tsi, t, m); |
2852 | } | |
2853 | ||
2854 | ||
2855 | /* Remove the statement pointed to by iterator I. The iterator is updated | |
6531d1be | 2856 | to the next statement. |
736432ee JL |
2857 | |
2858 | When REMOVE_EH_INFO is true we remove the statement pointed to by | |
2859 | iterator I from the EH tables. Otherwise we do not modify the EH | |
2860 | tables. | |
2861 | ||
2862 | Generally, REMOVE_EH_INFO should be true when the statement is going to | |
2863 | be removed from the IL and not reinserted elsewhere. */ | |
6de9cd9a DN |
2864 | |
2865 | void | |
736432ee | 2866 | bsi_remove (block_stmt_iterator *i, bool remove_eh_info) |
6de9cd9a DN |
2867 | { |
2868 | tree t = bsi_stmt (*i); | |
2869 | set_bb_for_stmt (t, NULL); | |
f430bae8 | 2870 | delink_stmt_imm_use (t); |
6de9cd9a | 2871 | tsi_delink (&i->tsi); |
f430bae8 | 2872 | mark_stmt_modified (t); |
736432ee JL |
2873 | if (remove_eh_info) |
2874 | remove_stmt_from_eh_region (t); | |
6de9cd9a DN |
2875 | } |
2876 | ||
2877 | ||
2878 | /* Move the statement at FROM so it comes right after the statement at TO. */ | |
2879 | ||
6531d1be | 2880 | void |
6de9cd9a DN |
2881 | bsi_move_after (block_stmt_iterator *from, block_stmt_iterator *to) |
2882 | { | |
2883 | tree stmt = bsi_stmt (*from); | |
736432ee | 2884 | bsi_remove (from, false); |
6de9cd9a | 2885 | bsi_insert_after (to, stmt, BSI_SAME_STMT); |
6531d1be | 2886 | } |
6de9cd9a DN |
2887 | |
2888 | ||
2889 | /* Move the statement at FROM so it comes right before the statement at TO. */ | |
2890 | ||
6531d1be | 2891 | void |
6de9cd9a DN |
2892 | bsi_move_before (block_stmt_iterator *from, block_stmt_iterator *to) |
2893 | { | |
2894 | tree stmt = bsi_stmt (*from); | |
736432ee | 2895 | bsi_remove (from, false); |
6de9cd9a DN |
2896 | bsi_insert_before (to, stmt, BSI_SAME_STMT); |
2897 | } | |
2898 | ||
2899 | ||
2900 | /* Move the statement at FROM to the end of basic block BB. */ | |
2901 | ||
2902 | void | |
2903 | bsi_move_to_bb_end (block_stmt_iterator *from, basic_block bb) | |
2904 | { | |
2905 | block_stmt_iterator last = bsi_last (bb); | |
6531d1be | 2906 | |
6de9cd9a DN |
2907 | /* Have to check bsi_end_p because it could be an empty block. */ |
2908 | if (!bsi_end_p (last) && is_ctrl_stmt (bsi_stmt (last))) | |
2909 | bsi_move_before (from, &last); | |
2910 | else | |
2911 | bsi_move_after (from, &last); | |
2912 | } | |
2913 | ||
2914 | ||
2915 | /* Replace the contents of the statement pointed to by iterator BSI | |
736432ee JL |
2916 | with STMT. If UPDATE_EH_INFO is true, the exception handling |
2917 | information of the original statement is moved to the new statement. */ | |
6de9cd9a DN |
2918 | |
2919 | void | |
736432ee | 2920 | bsi_replace (const block_stmt_iterator *bsi, tree stmt, bool update_eh_info) |
6de9cd9a DN |
2921 | { |
2922 | int eh_region; | |
2923 | tree orig_stmt = bsi_stmt (*bsi); | |
2924 | ||
2925 | SET_EXPR_LOCUS (stmt, EXPR_LOCUS (orig_stmt)); | |
2926 | set_bb_for_stmt (stmt, bsi->bb); | |
2927 | ||
2928 | /* Preserve EH region information from the original statement, if | |
2929 | requested by the caller. */ | |
736432ee | 2930 | if (update_eh_info) |
6de9cd9a DN |
2931 | { |
2932 | eh_region = lookup_stmt_eh_region (orig_stmt); | |
2933 | if (eh_region >= 0) | |
59bb84ef | 2934 | { |
736432ee | 2935 | remove_stmt_from_eh_region (orig_stmt); |
59bb84ef JL |
2936 | add_stmt_to_eh_region (stmt, eh_region); |
2937 | } | |
6de9cd9a DN |
2938 | } |
2939 | ||
b1ca239f | 2940 | delink_stmt_imm_use (orig_stmt); |
6de9cd9a | 2941 | *bsi_stmt_ptr (*bsi) = stmt; |
f430bae8 AM |
2942 | mark_stmt_modified (stmt); |
2943 | update_modified_stmts (stmt); | |
6de9cd9a DN |
2944 | } |
2945 | ||
2946 | ||
2947 | /* Insert the statement pointed-to by BSI into edge E. Every attempt | |
2948 | is made to place the statement in an existing basic block, but | |
2949 | sometimes that isn't possible. When it isn't possible, the edge is | |
2950 | split and the statement is added to the new block. | |
2951 | ||
2952 | In all cases, the returned *BSI points to the correct location. The | |
2953 | return value is true if insertion should be done after the location, | |
82b85a85 ZD |
2954 | or false if it should be done before the location. If new basic block |
2955 | has to be created, it is stored in *NEW_BB. */ | |
6de9cd9a DN |
2956 | |
2957 | static bool | |
82b85a85 ZD |
2958 | tree_find_edge_insert_loc (edge e, block_stmt_iterator *bsi, |
2959 | basic_block *new_bb) | |
6de9cd9a DN |
2960 | { |
2961 | basic_block dest, src; | |
2962 | tree tmp; | |
2963 | ||
2964 | dest = e->dest; | |
2965 | restart: | |
2966 | ||
2967 | /* If the destination has one predecessor which has no PHI nodes, | |
6531d1be | 2968 | insert there. Except for the exit block. |
6de9cd9a DN |
2969 | |
2970 | The requirement for no PHI nodes could be relaxed. Basically we | |
2971 | would have to examine the PHIs to prove that none of them used | |
e28d0cfb | 2972 | the value set by the statement we want to insert on E. That |
6de9cd9a | 2973 | hardly seems worth the effort. */ |
c5cbcccf | 2974 | if (single_pred_p (dest) |
6de9cd9a DN |
2975 | && ! phi_nodes (dest) |
2976 | && dest != EXIT_BLOCK_PTR) | |
2977 | { | |
2978 | *bsi = bsi_start (dest); | |
2979 | if (bsi_end_p (*bsi)) | |
2980 | return true; | |
2981 | ||
2982 | /* Make sure we insert after any leading labels. */ | |
2983 | tmp = bsi_stmt (*bsi); | |
2984 | while (TREE_CODE (tmp) == LABEL_EXPR) | |
2985 | { | |
2986 | bsi_next (bsi); | |
2987 | if (bsi_end_p (*bsi)) | |
2988 | break; | |
2989 | tmp = bsi_stmt (*bsi); | |
2990 | } | |
2991 | ||
2992 | if (bsi_end_p (*bsi)) | |
2993 | { | |
2994 | *bsi = bsi_last (dest); | |
2995 | return true; | |
2996 | } | |
2997 | else | |
2998 | return false; | |
2999 | } | |
3000 | ||
3001 | /* If the source has one successor, the edge is not abnormal and | |
3002 | the last statement does not end a basic block, insert there. | |
3003 | Except for the entry block. */ | |
3004 | src = e->src; | |
3005 | if ((e->flags & EDGE_ABNORMAL) == 0 | |
c5cbcccf | 3006 | && single_succ_p (src) |
6de9cd9a DN |
3007 | && src != ENTRY_BLOCK_PTR) |
3008 | { | |
3009 | *bsi = bsi_last (src); | |
3010 | if (bsi_end_p (*bsi)) | |
3011 | return true; | |
3012 | ||
3013 | tmp = bsi_stmt (*bsi); | |
3014 | if (!stmt_ends_bb_p (tmp)) | |
3015 | return true; | |
ce068299 JH |
3016 | |
3017 | /* Insert code just before returning the value. We may need to decompose | |
3018 | the return in the case it contains non-trivial operand. */ | |
3019 | if (TREE_CODE (tmp) == RETURN_EXPR) | |
3020 | { | |
3021 | tree op = TREE_OPERAND (tmp, 0); | |
7802250d | 3022 | if (op && !is_gimple_val (op)) |
ce068299 | 3023 | { |
07beea0d | 3024 | gcc_assert (TREE_CODE (op) == GIMPLE_MODIFY_STMT); |
ce068299 | 3025 | bsi_insert_before (bsi, op, BSI_NEW_STMT); |
07beea0d | 3026 | TREE_OPERAND (tmp, 0) = GIMPLE_STMT_OPERAND (op, 0); |
ce068299 JH |
3027 | } |
3028 | bsi_prev (bsi); | |
3029 | return true; | |
3030 | } | |
6de9cd9a DN |
3031 | } |
3032 | ||
3033 | /* Otherwise, create a new basic block, and split this edge. */ | |
3034 | dest = split_edge (e); | |
82b85a85 ZD |
3035 | if (new_bb) |
3036 | *new_bb = dest; | |
c5cbcccf | 3037 | e = single_pred_edge (dest); |
6de9cd9a DN |
3038 | goto restart; |
3039 | } | |
3040 | ||
3041 | ||
3042 | /* This routine will commit all pending edge insertions, creating any new | |
8e731e4e | 3043 | basic blocks which are necessary. */ |
6de9cd9a DN |
3044 | |
3045 | void | |
8e731e4e | 3046 | bsi_commit_edge_inserts (void) |
6de9cd9a DN |
3047 | { |
3048 | basic_block bb; | |
3049 | edge e; | |
628f6a4e | 3050 | edge_iterator ei; |
6de9cd9a | 3051 | |
c5cbcccf | 3052 | bsi_commit_one_edge_insert (single_succ_edge (ENTRY_BLOCK_PTR), NULL); |
6de9cd9a DN |
3053 | |
3054 | FOR_EACH_BB (bb) | |
628f6a4e | 3055 | FOR_EACH_EDGE (e, ei, bb->succs) |
edfaf675 | 3056 | bsi_commit_one_edge_insert (e, NULL); |
6de9cd9a DN |
3057 | } |
3058 | ||
3059 | ||
edfaf675 AM |
3060 | /* Commit insertions pending at edge E. If a new block is created, set NEW_BB |
3061 | to this block, otherwise set it to NULL. */ | |
6de9cd9a | 3062 | |
edfaf675 AM |
3063 | void |
3064 | bsi_commit_one_edge_insert (edge e, basic_block *new_bb) | |
6de9cd9a | 3065 | { |
edfaf675 AM |
3066 | if (new_bb) |
3067 | *new_bb = NULL; | |
6de9cd9a DN |
3068 | if (PENDING_STMT (e)) |
3069 | { | |
3070 | block_stmt_iterator bsi; | |
3071 | tree stmt = PENDING_STMT (e); | |
3072 | ||
3073 | PENDING_STMT (e) = NULL_TREE; | |
3074 | ||
edfaf675 | 3075 | if (tree_find_edge_insert_loc (e, &bsi, new_bb)) |
6de9cd9a DN |
3076 | bsi_insert_after (&bsi, stmt, BSI_NEW_STMT); |
3077 | else | |
3078 | bsi_insert_before (&bsi, stmt, BSI_NEW_STMT); | |
3079 | } | |
3080 | } | |
3081 | ||
3082 | ||
3083 | /* Add STMT to the pending list of edge E. No actual insertion is | |
3084 | made until a call to bsi_commit_edge_inserts () is made. */ | |
3085 | ||
3086 | void | |
3087 | bsi_insert_on_edge (edge e, tree stmt) | |
3088 | { | |
3089 | append_to_statement_list (stmt, &PENDING_STMT (e)); | |
3090 | } | |
3091 | ||
adb35797 KH |
3092 | /* Similar to bsi_insert_on_edge+bsi_commit_edge_inserts. If a new |
3093 | block has to be created, it is returned. */ | |
82b85a85 ZD |
3094 | |
3095 | basic_block | |
3096 | bsi_insert_on_edge_immediate (edge e, tree stmt) | |
3097 | { | |
3098 | block_stmt_iterator bsi; | |
3099 | basic_block new_bb = NULL; | |
3100 | ||
1e128c5f | 3101 | gcc_assert (!PENDING_STMT (e)); |
82b85a85 ZD |
3102 | |
3103 | if (tree_find_edge_insert_loc (e, &bsi, &new_bb)) | |
3104 | bsi_insert_after (&bsi, stmt, BSI_NEW_STMT); | |
3105 | else | |
3106 | bsi_insert_before (&bsi, stmt, BSI_NEW_STMT); | |
3107 | ||
3108 | return new_bb; | |
3109 | } | |
6de9cd9a | 3110 | |
6de9cd9a DN |
3111 | /*--------------------------------------------------------------------------- |
3112 | Tree specific functions for CFG manipulation | |
3113 | ---------------------------------------------------------------------------*/ | |
3114 | ||
4f7db7f7 KH |
3115 | /* Reinstall those PHI arguments queued in OLD_EDGE to NEW_EDGE. */ |
3116 | ||
3117 | static void | |
3118 | reinstall_phi_args (edge new_edge, edge old_edge) | |
3119 | { | |
3120 | tree var, phi; | |
3121 | ||
3122 | if (!PENDING_STMT (old_edge)) | |
3123 | return; | |
6531d1be | 3124 | |
4f7db7f7 KH |
3125 | for (var = PENDING_STMT (old_edge), phi = phi_nodes (new_edge->dest); |
3126 | var && phi; | |
3127 | var = TREE_CHAIN (var), phi = PHI_CHAIN (phi)) | |
3128 | { | |
3129 | tree result = TREE_PURPOSE (var); | |
3130 | tree arg = TREE_VALUE (var); | |
3131 | ||
3132 | gcc_assert (result == PHI_RESULT (phi)); | |
3133 | ||
d2e398df | 3134 | add_phi_arg (phi, arg, new_edge); |
4f7db7f7 KH |
3135 | } |
3136 | ||
3137 | PENDING_STMT (old_edge) = NULL; | |
3138 | } | |
3139 | ||
2a8a8292 | 3140 | /* Returns the basic block after which the new basic block created |
b9a66240 ZD |
3141 | by splitting edge EDGE_IN should be placed. Tries to keep the new block |
3142 | near its "logical" location. This is of most help to humans looking | |
3143 | at debugging dumps. */ | |
3144 | ||
3145 | static basic_block | |
3146 | split_edge_bb_loc (edge edge_in) | |
3147 | { | |
3148 | basic_block dest = edge_in->dest; | |
3149 | ||
3150 | if (dest->prev_bb && find_edge (dest->prev_bb, dest)) | |
3151 | return edge_in->src; | |
3152 | else | |
3153 | return dest->prev_bb; | |
3154 | } | |
3155 | ||
6de9cd9a DN |
3156 | /* Split a (typically critical) edge EDGE_IN. Return the new block. |
3157 | Abort on abnormal edges. */ | |
3158 | ||
3159 | static basic_block | |
3160 | tree_split_edge (edge edge_in) | |
3161 | { | |
4741d956 | 3162 | basic_block new_bb, after_bb, dest; |
6de9cd9a | 3163 | edge new_edge, e; |
6de9cd9a DN |
3164 | |
3165 | /* Abnormal edges cannot be split. */ | |
1e128c5f | 3166 | gcc_assert (!(edge_in->flags & EDGE_ABNORMAL)); |
6de9cd9a | 3167 | |
6de9cd9a DN |
3168 | dest = edge_in->dest; |
3169 | ||
b9a66240 | 3170 | after_bb = split_edge_bb_loc (edge_in); |
6de9cd9a DN |
3171 | |
3172 | new_bb = create_empty_bb (after_bb); | |
b829f3fa JH |
3173 | new_bb->frequency = EDGE_FREQUENCY (edge_in); |
3174 | new_bb->count = edge_in->count; | |
6de9cd9a | 3175 | new_edge = make_edge (new_bb, dest, EDGE_FALLTHRU); |
b829f3fa JH |
3176 | new_edge->probability = REG_BR_PROB_BASE; |
3177 | new_edge->count = edge_in->count; | |
6de9cd9a | 3178 | |
1e128c5f GB |
3179 | e = redirect_edge_and_branch (edge_in, new_bb); |
3180 | gcc_assert (e); | |
4f7db7f7 | 3181 | reinstall_phi_args (new_edge, e); |
6de9cd9a DN |
3182 | |
3183 | return new_bb; | |
3184 | } | |
3185 | ||
3186 | ||
3187 | /* Return true when BB has label LABEL in it. */ | |
3188 | ||
3189 | static bool | |
3190 | has_label_p (basic_block bb, tree label) | |
3191 | { | |
3192 | block_stmt_iterator bsi; | |
3193 | ||
3194 | for (bsi = bsi_start (bb); !bsi_end_p (bsi); bsi_next (&bsi)) | |
3195 | { | |
3196 | tree stmt = bsi_stmt (bsi); | |
3197 | ||
3198 | if (TREE_CODE (stmt) != LABEL_EXPR) | |
3199 | return false; | |
3200 | if (LABEL_EXPR_LABEL (stmt) == label) | |
3201 | return true; | |
3202 | } | |
3203 | return false; | |
3204 | } | |
3205 | ||
3206 | ||
3207 | /* Callback for walk_tree, check that all elements with address taken are | |
7a442a1d SB |
3208 | properly noticed as such. The DATA is an int* that is 1 if TP was seen |
3209 | inside a PHI node. */ | |
6de9cd9a DN |
3210 | |
3211 | static tree | |
2fbe90f2 | 3212 | verify_expr (tree *tp, int *walk_subtrees, void *data ATTRIBUTE_UNUSED) |
6de9cd9a DN |
3213 | { |
3214 | tree t = *tp, x; | |
7a442a1d | 3215 | bool in_phi = (data != NULL); |
6de9cd9a DN |
3216 | |
3217 | if (TYPE_P (t)) | |
3218 | *walk_subtrees = 0; | |
6531d1be | 3219 | |
e8ca4159 | 3220 | /* Check operand N for being valid GIMPLE and give error MSG if not. */ |
2fbe90f2 | 3221 | #define CHECK_OP(N, MSG) \ |
e8ca4159 | 3222 | do { if (!is_gimple_val (TREE_OPERAND (t, N))) \ |
2fbe90f2 | 3223 | { error (MSG); return TREE_OPERAND (t, N); }} while (0) |
6de9cd9a DN |
3224 | |
3225 | switch (TREE_CODE (t)) | |
3226 | { | |
3227 | case SSA_NAME: | |
3228 | if (SSA_NAME_IN_FREE_LIST (t)) | |
3229 | { | |
3230 | error ("SSA name in freelist but still referenced"); | |
3231 | return *tp; | |
3232 | } | |
3233 | break; | |
3234 | ||
0bca51f0 DN |
3235 | case ASSERT_EXPR: |
3236 | x = fold (ASSERT_EXPR_COND (t)); | |
3237 | if (x == boolean_false_node) | |
3238 | { | |
3239 | error ("ASSERT_EXPR with an always-false condition"); | |
3240 | return *tp; | |
3241 | } | |
3242 | break; | |
3243 | ||
6de9cd9a | 3244 | case MODIFY_EXPR: |
07beea0d AH |
3245 | gcc_unreachable (); |
3246 | ||
3247 | case GIMPLE_MODIFY_STMT: | |
3248 | x = GIMPLE_STMT_OPERAND (t, 0); | |
6de9cd9a DN |
3249 | if (TREE_CODE (x) == BIT_FIELD_REF |
3250 | && is_gimple_reg (TREE_OPERAND (x, 0))) | |
3251 | { | |
3252 | error ("GIMPLE register modified with BIT_FIELD_REF"); | |
2fbe90f2 | 3253 | return t; |
6de9cd9a DN |
3254 | } |
3255 | break; | |
3256 | ||
3257 | case ADDR_EXPR: | |
81fc3052 DB |
3258 | { |
3259 | bool old_invariant; | |
3260 | bool old_constant; | |
3261 | bool old_side_effects; | |
3262 | bool new_invariant; | |
3263 | bool new_constant; | |
3264 | bool new_side_effects; | |
3265 | ||
3266 | /* ??? tree-ssa-alias.c may have overlooked dead PHI nodes, missing | |
3267 | dead PHIs that take the address of something. But if the PHI | |
3268 | result is dead, the fact that it takes the address of anything | |
3269 | is irrelevant. Because we can not tell from here if a PHI result | |
3270 | is dead, we just skip this check for PHIs altogether. This means | |
3271 | we may be missing "valid" checks, but what can you do? | |
3272 | This was PR19217. */ | |
3273 | if (in_phi) | |
3274 | break; | |
7a442a1d | 3275 | |
81fc3052 DB |
3276 | old_invariant = TREE_INVARIANT (t); |
3277 | old_constant = TREE_CONSTANT (t); | |
3278 | old_side_effects = TREE_SIDE_EFFECTS (t); | |
3279 | ||
127203ac | 3280 | recompute_tree_invariant_for_addr_expr (t); |
81fc3052 DB |
3281 | new_invariant = TREE_INVARIANT (t); |
3282 | new_side_effects = TREE_SIDE_EFFECTS (t); | |
3283 | new_constant = TREE_CONSTANT (t); | |
3284 | ||
3285 | if (old_invariant != new_invariant) | |
3286 | { | |
3287 | error ("invariant not recomputed when ADDR_EXPR changed"); | |
3288 | return t; | |
3289 | } | |
3290 | ||
3291 | if (old_constant != new_constant) | |
3292 | { | |
3293 | error ("constant not recomputed when ADDR_EXPR changed"); | |
3294 | return t; | |
3295 | } | |
3296 | if (old_side_effects != new_side_effects) | |
3297 | { | |
3298 | error ("side effects not recomputed when ADDR_EXPR changed"); | |
3299 | return t; | |
3300 | } | |
3301 | ||
3302 | /* Skip any references (they will be checked when we recurse down the | |
3303 | tree) and ensure that any variable used as a prefix is marked | |
3304 | addressable. */ | |
3305 | for (x = TREE_OPERAND (t, 0); | |
3306 | handled_component_p (x); | |
3307 | x = TREE_OPERAND (x, 0)) | |
3308 | ; | |
3309 | ||
3310 | if (TREE_CODE (x) != VAR_DECL && TREE_CODE (x) != PARM_DECL) | |
3311 | return NULL; | |
3312 | if (!TREE_ADDRESSABLE (x)) | |
3313 | { | |
3314 | error ("address taken, but ADDRESSABLE bit not set"); | |
3315 | return x; | |
3316 | } | |
3317 | break; | |
3318 | } | |
6de9cd9a DN |
3319 | |
3320 | case COND_EXPR: | |
a6234684 | 3321 | x = COND_EXPR_COND (t); |
6de9cd9a DN |
3322 | if (TREE_CODE (TREE_TYPE (x)) != BOOLEAN_TYPE) |
3323 | { | |
3324 | error ("non-boolean used in condition"); | |
3325 | return x; | |
3326 | } | |
9c691961 AP |
3327 | if (!is_gimple_condexpr (x)) |
3328 | { | |
ab532386 | 3329 | error ("invalid conditional operand"); |
9c691961 AP |
3330 | return x; |
3331 | } | |
6de9cd9a DN |
3332 | break; |
3333 | ||
3334 | case NOP_EXPR: | |
3335 | case CONVERT_EXPR: | |
3336 | case FIX_TRUNC_EXPR: | |
6de9cd9a DN |
3337 | case FLOAT_EXPR: |
3338 | case NEGATE_EXPR: | |
3339 | case ABS_EXPR: | |
3340 | case BIT_NOT_EXPR: | |
3341 | case NON_LVALUE_EXPR: | |
3342 | case TRUTH_NOT_EXPR: | |
ab532386 | 3343 | CHECK_OP (0, "invalid operand to unary operator"); |
6de9cd9a DN |
3344 | break; |
3345 | ||
3346 | case REALPART_EXPR: | |
3347 | case IMAGPART_EXPR: | |
2fbe90f2 RK |
3348 | case COMPONENT_REF: |
3349 | case ARRAY_REF: | |
3350 | case ARRAY_RANGE_REF: | |
3351 | case BIT_FIELD_REF: | |
3352 | case VIEW_CONVERT_EXPR: | |
3353 | /* We have a nest of references. Verify that each of the operands | |
3354 | that determine where to reference is either a constant or a variable, | |
3355 | verify that the base is valid, and then show we've already checked | |
3356 | the subtrees. */ | |
afe84921 | 3357 | while (handled_component_p (t)) |
2fbe90f2 RK |
3358 | { |
3359 | if (TREE_CODE (t) == COMPONENT_REF && TREE_OPERAND (t, 2)) | |
ab532386 | 3360 | CHECK_OP (2, "invalid COMPONENT_REF offset operator"); |
2fbe90f2 RK |
3361 | else if (TREE_CODE (t) == ARRAY_REF |
3362 | || TREE_CODE (t) == ARRAY_RANGE_REF) | |
3363 | { | |
ab532386 | 3364 | CHECK_OP (1, "invalid array index"); |
2fbe90f2 | 3365 | if (TREE_OPERAND (t, 2)) |
ab532386 | 3366 | CHECK_OP (2, "invalid array lower bound"); |
2fbe90f2 | 3367 | if (TREE_OPERAND (t, 3)) |
ab532386 | 3368 | CHECK_OP (3, "invalid array stride"); |
2fbe90f2 RK |
3369 | } |
3370 | else if (TREE_CODE (t) == BIT_FIELD_REF) | |
3371 | { | |
ab532386 JM |
3372 | CHECK_OP (1, "invalid operand to BIT_FIELD_REF"); |
3373 | CHECK_OP (2, "invalid operand to BIT_FIELD_REF"); | |
2fbe90f2 RK |
3374 | } |
3375 | ||
3376 | t = TREE_OPERAND (t, 0); | |
3377 | } | |
3378 | ||
6615c446 | 3379 | if (!CONSTANT_CLASS_P (t) && !is_gimple_lvalue (t)) |
2fbe90f2 | 3380 | { |
ab532386 | 3381 | error ("invalid reference prefix"); |
2fbe90f2 RK |
3382 | return t; |
3383 | } | |
3384 | *walk_subtrees = 0; | |
6de9cd9a DN |
3385 | break; |
3386 | ||
3387 | case LT_EXPR: | |
3388 | case LE_EXPR: | |
3389 | case GT_EXPR: | |
3390 | case GE_EXPR: | |
3391 | case EQ_EXPR: | |
3392 | case NE_EXPR: | |
3393 | case UNORDERED_EXPR: | |
3394 | case ORDERED_EXPR: | |
3395 | case UNLT_EXPR: | |
3396 | case UNLE_EXPR: | |
3397 | case UNGT_EXPR: | |
3398 | case UNGE_EXPR: | |
3399 | case UNEQ_EXPR: | |
d1a7edaf | 3400 | case LTGT_EXPR: |
6de9cd9a DN |
3401 | case PLUS_EXPR: |
3402 | case MINUS_EXPR: | |
3403 | case MULT_EXPR: | |
3404 | case TRUNC_DIV_EXPR: | |
3405 | case CEIL_DIV_EXPR: | |
3406 | case FLOOR_DIV_EXPR: | |
3407 | case ROUND_DIV_EXPR: | |
3408 | case TRUNC_MOD_EXPR: | |
3409 | case CEIL_MOD_EXPR: | |
3410 | case FLOOR_MOD_EXPR: | |
3411 | case ROUND_MOD_EXPR: | |
3412 | case RDIV_EXPR: | |
3413 | case EXACT_DIV_EXPR: | |
3414 | case MIN_EXPR: | |
3415 | case MAX_EXPR: | |
3416 | case LSHIFT_EXPR: | |
3417 | case RSHIFT_EXPR: | |
3418 | case LROTATE_EXPR: | |
3419 | case RROTATE_EXPR: | |
3420 | case BIT_IOR_EXPR: | |
3421 | case BIT_XOR_EXPR: | |
3422 | case BIT_AND_EXPR: | |
ab532386 JM |
3423 | CHECK_OP (0, "invalid operand to binary operator"); |
3424 | CHECK_OP (1, "invalid operand to binary operator"); | |
6de9cd9a DN |
3425 | break; |
3426 | ||
84816907 JM |
3427 | case CONSTRUCTOR: |
3428 | if (TREE_CONSTANT (t) && TREE_CODE (TREE_TYPE (t)) == VECTOR_TYPE) | |
3429 | *walk_subtrees = 0; | |
3430 | break; | |
3431 | ||
6de9cd9a DN |
3432 | default: |
3433 | break; | |
3434 | } | |
3435 | return NULL; | |
2fbe90f2 RK |
3436 | |
3437 | #undef CHECK_OP | |
6de9cd9a DN |
3438 | } |
3439 | ||
3440 | ||
3441 | /* Verify STMT, return true if STMT is not in GIMPLE form. | |
3442 | TODO: Implement type checking. */ | |
3443 | ||
3444 | static bool | |
1eaba2f2 | 3445 | verify_stmt (tree stmt, bool last_in_block) |
6de9cd9a DN |
3446 | { |
3447 | tree addr; | |
3448 | ||
50674e96 DN |
3449 | if (OMP_DIRECTIVE_P (stmt)) |
3450 | { | |
3451 | /* OpenMP directives are validated by the FE and never operated | |
3452 | on by the optimizers. Furthermore, OMP_FOR may contain | |
3453 | non-gimple expressions when the main index variable has had | |
3454 | its address taken. This does not affect the loop itself | |
3455 | because the header of an OMP_FOR is merely used to determine | |
3456 | how to setup the parallel iteration. */ | |
3457 | return false; | |
3458 | } | |
3459 | ||
6de9cd9a DN |
3460 | if (!is_gimple_stmt (stmt)) |
3461 | { | |
ab532386 | 3462 | error ("is not a valid GIMPLE statement"); |
1eaba2f2 | 3463 | goto fail; |
6de9cd9a DN |
3464 | } |
3465 | ||
3466 | addr = walk_tree (&stmt, verify_expr, NULL, NULL); | |
3467 | if (addr) | |
3468 | { | |
3469 | debug_generic_stmt (addr); | |
3470 | return true; | |
3471 | } | |
3472 | ||
1eaba2f2 RH |
3473 | /* If the statement is marked as part of an EH region, then it is |
3474 | expected that the statement could throw. Verify that when we | |
3475 | have optimizations that simplify statements such that we prove | |
3476 | that they cannot throw, that we update other data structures | |
3477 | to match. */ | |
3478 | if (lookup_stmt_eh_region (stmt) >= 0) | |
3479 | { | |
3480 | if (!tree_could_throw_p (stmt)) | |
3481 | { | |
ab532386 | 3482 | error ("statement marked for throw, but doesn%'t"); |
1eaba2f2 RH |
3483 | goto fail; |
3484 | } | |
3485 | if (!last_in_block && tree_can_throw_internal (stmt)) | |
3486 | { | |
ab532386 | 3487 | error ("statement marked for throw in middle of block"); |
1eaba2f2 RH |
3488 | goto fail; |
3489 | } | |
3490 | } | |
3491 | ||
6de9cd9a | 3492 | return false; |
1eaba2f2 RH |
3493 | |
3494 | fail: | |
3495 | debug_generic_stmt (stmt); | |
3496 | return true; | |
6de9cd9a DN |
3497 | } |
3498 | ||
3499 | ||
3500 | /* Return true when the T can be shared. */ | |
3501 | ||
3502 | static bool | |
3503 | tree_node_can_be_shared (tree t) | |
3504 | { | |
6615c446 | 3505 | if (IS_TYPE_OR_DECL_P (t) |
6de9cd9a | 3506 | || is_gimple_min_invariant (t) |
5e23162d | 3507 | || TREE_CODE (t) == SSA_NAME |
953ff289 DN |
3508 | || t == error_mark_node |
3509 | || TREE_CODE (t) == IDENTIFIER_NODE) | |
6de9cd9a DN |
3510 | return true; |
3511 | ||
92b6dff3 JL |
3512 | if (TREE_CODE (t) == CASE_LABEL_EXPR) |
3513 | return true; | |
3514 | ||
44de5aeb | 3515 | while (((TREE_CODE (t) == ARRAY_REF || TREE_CODE (t) == ARRAY_RANGE_REF) |
953ff289 DN |
3516 | && is_gimple_min_invariant (TREE_OPERAND (t, 1))) |
3517 | || TREE_CODE (t) == COMPONENT_REF | |
3518 | || TREE_CODE (t) == REALPART_EXPR | |
3519 | || TREE_CODE (t) == IMAGPART_EXPR) | |
6de9cd9a DN |
3520 | t = TREE_OPERAND (t, 0); |
3521 | ||
3522 | if (DECL_P (t)) | |
3523 | return true; | |
3524 | ||
3525 | return false; | |
3526 | } | |
3527 | ||
3528 | ||
3529 | /* Called via walk_trees. Verify tree sharing. */ | |
3530 | ||
3531 | static tree | |
3532 | verify_node_sharing (tree * tp, int *walk_subtrees, void *data) | |
3533 | { | |
3534 | htab_t htab = (htab_t) data; | |
3535 | void **slot; | |
3536 | ||
3537 | if (tree_node_can_be_shared (*tp)) | |
3538 | { | |
3539 | *walk_subtrees = false; | |
3540 | return NULL; | |
3541 | } | |
3542 | ||
3543 | slot = htab_find_slot (htab, *tp, INSERT); | |
3544 | if (*slot) | |
858904db | 3545 | return (tree) *slot; |
6de9cd9a DN |
3546 | *slot = *tp; |
3547 | ||
3548 | return NULL; | |
3549 | } | |
3550 | ||
3551 | ||
07beea0d AH |
3552 | /* Helper function for verify_gimple_tuples. */ |
3553 | ||
3554 | static tree | |
3555 | verify_gimple_tuples_1 (tree *tp, int *walk_subtrees ATTRIBUTE_UNUSED, | |
3556 | void *data ATTRIBUTE_UNUSED) | |
3557 | { | |
3558 | switch (TREE_CODE (*tp)) | |
3559 | { | |
3560 | case MODIFY_EXPR: | |
3561 | error ("unexpected non-tuple"); | |
3562 | debug_tree (*tp); | |
3563 | gcc_unreachable (); | |
3564 | return NULL_TREE; | |
3565 | ||
3566 | default: | |
3567 | return NULL_TREE; | |
3568 | } | |
3569 | } | |
3570 | ||
3571 | /* Verify that there are no trees that should have been converted to | |
3572 | gimple tuples. Return true if T contains a node that should have | |
3573 | been converted to a gimple tuple, but hasn't. */ | |
3574 | ||
3575 | static bool | |
3576 | verify_gimple_tuples (tree t) | |
3577 | { | |
3578 | return walk_tree (&t, verify_gimple_tuples_1, NULL, NULL) != NULL; | |
3579 | } | |
3580 | ||
6de9cd9a DN |
3581 | /* Verify the GIMPLE statement chain. */ |
3582 | ||
3583 | void | |
3584 | verify_stmts (void) | |
3585 | { | |
3586 | basic_block bb; | |
3587 | block_stmt_iterator bsi; | |
3588 | bool err = false; | |
3589 | htab_t htab; | |
3590 | tree addr; | |
3591 | ||
3592 | timevar_push (TV_TREE_STMT_VERIFY); | |
3593 | htab = htab_create (37, htab_hash_pointer, htab_eq_pointer, NULL); | |
3594 | ||
3595 | FOR_EACH_BB (bb) | |
3596 | { | |
3597 | tree phi; | |
3598 | int i; | |
3599 | ||
17192884 | 3600 | for (phi = phi_nodes (bb); phi; phi = PHI_CHAIN (phi)) |
6de9cd9a DN |
3601 | { |
3602 | int phi_num_args = PHI_NUM_ARGS (phi); | |
3603 | ||
8de1fc1b KH |
3604 | if (bb_for_stmt (phi) != bb) |
3605 | { | |
ab532386 | 3606 | error ("bb_for_stmt (phi) is set to a wrong basic block"); |
8de1fc1b KH |
3607 | err |= true; |
3608 | } | |
3609 | ||
6de9cd9a DN |
3610 | for (i = 0; i < phi_num_args; i++) |
3611 | { | |
3612 | tree t = PHI_ARG_DEF (phi, i); | |
3613 | tree addr; | |
3614 | ||
3615 | /* Addressable variables do have SSA_NAMEs but they | |
3616 | are not considered gimple values. */ | |
3617 | if (TREE_CODE (t) != SSA_NAME | |
3618 | && TREE_CODE (t) != FUNCTION_DECL | |
3619 | && !is_gimple_val (t)) | |
3620 | { | |
3621 | error ("PHI def is not a GIMPLE value"); | |
3622 | debug_generic_stmt (phi); | |
3623 | debug_generic_stmt (t); | |
3624 | err |= true; | |
3625 | } | |
3626 | ||
7a442a1d | 3627 | addr = walk_tree (&t, verify_expr, (void *) 1, NULL); |
6de9cd9a DN |
3628 | if (addr) |
3629 | { | |
3630 | debug_generic_stmt (addr); | |
3631 | err |= true; | |
3632 | } | |
3633 | ||
3634 | addr = walk_tree (&t, verify_node_sharing, htab, NULL); | |
3635 | if (addr) | |
3636 | { | |
ab532386 | 3637 | error ("incorrect sharing of tree nodes"); |
6de9cd9a DN |
3638 | debug_generic_stmt (phi); |
3639 | debug_generic_stmt (addr); | |
3640 | err |= true; | |
3641 | } | |
3642 | } | |
3643 | } | |
3644 | ||
1eaba2f2 | 3645 | for (bsi = bsi_start (bb); !bsi_end_p (bsi); ) |
6de9cd9a DN |
3646 | { |
3647 | tree stmt = bsi_stmt (bsi); | |
8de1fc1b | 3648 | |
07beea0d AH |
3649 | err |= verify_gimple_tuples (stmt); |
3650 | ||
8de1fc1b KH |
3651 | if (bb_for_stmt (stmt) != bb) |
3652 | { | |
ab532386 | 3653 | error ("bb_for_stmt (stmt) is set to a wrong basic block"); |
8de1fc1b KH |
3654 | err |= true; |
3655 | } | |
3656 | ||
1eaba2f2 RH |
3657 | bsi_next (&bsi); |
3658 | err |= verify_stmt (stmt, bsi_end_p (bsi)); | |
6de9cd9a DN |
3659 | addr = walk_tree (&stmt, verify_node_sharing, htab, NULL); |
3660 | if (addr) | |
3661 | { | |
ab532386 | 3662 | error ("incorrect sharing of tree nodes"); |
6de9cd9a DN |
3663 | debug_generic_stmt (stmt); |
3664 | debug_generic_stmt (addr); | |
3665 | err |= true; | |
3666 | } | |
3667 | } | |
3668 | } | |
3669 | ||
3670 | if (err) | |
ab532386 | 3671 | internal_error ("verify_stmts failed"); |
6de9cd9a DN |
3672 | |
3673 | htab_delete (htab); | |
3674 | timevar_pop (TV_TREE_STMT_VERIFY); | |
3675 | } | |
3676 | ||
3677 | ||
3678 | /* Verifies that the flow information is OK. */ | |
3679 | ||
3680 | static int | |
3681 | tree_verify_flow_info (void) | |
3682 | { | |
3683 | int err = 0; | |
3684 | basic_block bb; | |
3685 | block_stmt_iterator bsi; | |
3686 | tree stmt; | |
3687 | edge e; | |
628f6a4e | 3688 | edge_iterator ei; |
6de9cd9a DN |
3689 | |
3690 | if (ENTRY_BLOCK_PTR->stmt_list) | |
3691 | { | |
ab532386 | 3692 | error ("ENTRY_BLOCK has a statement list associated with it"); |
6de9cd9a DN |
3693 | err = 1; |
3694 | } | |
3695 | ||
3696 | if (EXIT_BLOCK_PTR->stmt_list) | |
3697 | { | |
ab532386 | 3698 | error ("EXIT_BLOCK has a statement list associated with it"); |
6de9cd9a DN |
3699 | err = 1; |
3700 | } | |
3701 | ||
628f6a4e | 3702 | FOR_EACH_EDGE (e, ei, EXIT_BLOCK_PTR->preds) |
6de9cd9a DN |
3703 | if (e->flags & EDGE_FALLTHRU) |
3704 | { | |
ab532386 | 3705 | error ("fallthru to exit from bb %d", e->src->index); |
6de9cd9a DN |
3706 | err = 1; |
3707 | } | |
3708 | ||
3709 | FOR_EACH_BB (bb) | |
3710 | { | |
3711 | bool found_ctrl_stmt = false; | |
3712 | ||
548414c6 KH |
3713 | stmt = NULL_TREE; |
3714 | ||
6de9cd9a DN |
3715 | /* Skip labels on the start of basic block. */ |
3716 | for (bsi = bsi_start (bb); !bsi_end_p (bsi); bsi_next (&bsi)) | |
3717 | { | |
548414c6 KH |
3718 | tree prev_stmt = stmt; |
3719 | ||
3720 | stmt = bsi_stmt (bsi); | |
3721 | ||
3722 | if (TREE_CODE (stmt) != LABEL_EXPR) | |
6de9cd9a DN |
3723 | break; |
3724 | ||
548414c6 KH |
3725 | if (prev_stmt && DECL_NONLOCAL (LABEL_EXPR_LABEL (stmt))) |
3726 | { | |
953ff289 DN |
3727 | error ("nonlocal label "); |
3728 | print_generic_expr (stderr, LABEL_EXPR_LABEL (stmt), 0); | |
3729 | fprintf (stderr, " is not first in a sequence of labels in bb %d", | |
3730 | bb->index); | |
548414c6 KH |
3731 | err = 1; |
3732 | } | |
3733 | ||
3734 | if (label_to_block (LABEL_EXPR_LABEL (stmt)) != bb) | |
6de9cd9a | 3735 | { |
953ff289 DN |
3736 | error ("label "); |
3737 | print_generic_expr (stderr, LABEL_EXPR_LABEL (stmt), 0); | |
3738 | fprintf (stderr, " to block does not match in bb %d", | |
3739 | bb->index); | |
6de9cd9a DN |
3740 | err = 1; |
3741 | } | |
3742 | ||
548414c6 | 3743 | if (decl_function_context (LABEL_EXPR_LABEL (stmt)) |
6de9cd9a DN |
3744 | != current_function_decl) |
3745 | { | |
953ff289 DN |
3746 | error ("label "); |
3747 | print_generic_expr (stderr, LABEL_EXPR_LABEL (stmt), 0); | |
3748 | fprintf (stderr, " has incorrect context in bb %d", | |
3749 | bb->index); | |
6de9cd9a DN |
3750 | err = 1; |
3751 | } | |
3752 | } | |
3753 | ||
3754 | /* Verify that body of basic block BB is free of control flow. */ | |
3755 | for (; !bsi_end_p (bsi); bsi_next (&bsi)) | |
3756 | { | |
3757 | tree stmt = bsi_stmt (bsi); | |
3758 | ||
3759 | if (found_ctrl_stmt) | |
3760 | { | |
ab532386 | 3761 | error ("control flow in the middle of basic block %d", |
6de9cd9a DN |
3762 | bb->index); |
3763 | err = 1; | |
3764 | } | |
3765 | ||
3766 | if (stmt_ends_bb_p (stmt)) | |
3767 | found_ctrl_stmt = true; | |
3768 | ||
3769 | if (TREE_CODE (stmt) == LABEL_EXPR) | |
3770 | { | |
953ff289 DN |
3771 | error ("label "); |
3772 | print_generic_expr (stderr, LABEL_EXPR_LABEL (stmt), 0); | |
3773 | fprintf (stderr, " in the middle of basic block %d", bb->index); | |
6de9cd9a DN |
3774 | err = 1; |
3775 | } | |
3776 | } | |
953ff289 | 3777 | |
6de9cd9a DN |
3778 | bsi = bsi_last (bb); |
3779 | if (bsi_end_p (bsi)) | |
3780 | continue; | |
3781 | ||
3782 | stmt = bsi_stmt (bsi); | |
3783 | ||
cc7220fd JH |
3784 | err |= verify_eh_edges (stmt); |
3785 | ||
6de9cd9a DN |
3786 | if (is_ctrl_stmt (stmt)) |
3787 | { | |
628f6a4e | 3788 | FOR_EACH_EDGE (e, ei, bb->succs) |
6de9cd9a DN |
3789 | if (e->flags & EDGE_FALLTHRU) |
3790 | { | |
ab532386 | 3791 | error ("fallthru edge after a control statement in bb %d", |
6de9cd9a DN |
3792 | bb->index); |
3793 | err = 1; | |
3794 | } | |
3795 | } | |
3796 | ||
36b24193 ZD |
3797 | if (TREE_CODE (stmt) != COND_EXPR) |
3798 | { | |
3799 | /* Verify that there are no edges with EDGE_TRUE/FALSE_FLAG set | |
3800 | after anything else but if statement. */ | |
3801 | FOR_EACH_EDGE (e, ei, bb->succs) | |
3802 | if (e->flags & (EDGE_TRUE_VALUE | EDGE_FALSE_VALUE)) | |
3803 | { | |
3804 | error ("true/false edge after a non-COND_EXPR in bb %d", | |
3805 | bb->index); | |
3806 | err = 1; | |
3807 | } | |
3808 | } | |
3809 | ||
6de9cd9a DN |
3810 | switch (TREE_CODE (stmt)) |
3811 | { | |
3812 | case COND_EXPR: | |
3813 | { | |
3814 | edge true_edge; | |
3815 | edge false_edge; | |
3816 | if (TREE_CODE (COND_EXPR_THEN (stmt)) != GOTO_EXPR | |
3817 | || TREE_CODE (COND_EXPR_ELSE (stmt)) != GOTO_EXPR) | |
3818 | { | |
ab532386 | 3819 | error ("structured COND_EXPR at the end of bb %d", bb->index); |
6de9cd9a DN |
3820 | err = 1; |
3821 | } | |
3822 | ||
3823 | extract_true_false_edges_from_block (bb, &true_edge, &false_edge); | |
3824 | ||
3825 | if (!true_edge || !false_edge | |
3826 | || !(true_edge->flags & EDGE_TRUE_VALUE) | |
3827 | || !(false_edge->flags & EDGE_FALSE_VALUE) | |
3828 | || (true_edge->flags & (EDGE_FALLTHRU | EDGE_ABNORMAL)) | |
3829 | || (false_edge->flags & (EDGE_FALLTHRU | EDGE_ABNORMAL)) | |
628f6a4e | 3830 | || EDGE_COUNT (bb->succs) >= 3) |
6de9cd9a | 3831 | { |
ab532386 | 3832 | error ("wrong outgoing edge flags at end of bb %d", |
6de9cd9a DN |
3833 | bb->index); |
3834 | err = 1; | |
3835 | } | |
3836 | ||
3837 | if (!has_label_p (true_edge->dest, | |
3838 | GOTO_DESTINATION (COND_EXPR_THEN (stmt)))) | |
3839 | { | |
ab532386 | 3840 | error ("%<then%> label does not match edge at end of bb %d", |
6de9cd9a DN |
3841 | bb->index); |
3842 | err = 1; | |
3843 | } | |
3844 | ||
3845 | if (!has_label_p (false_edge->dest, | |
3846 | GOTO_DESTINATION (COND_EXPR_ELSE (stmt)))) | |
3847 | { | |
ab532386 | 3848 | error ("%<else%> label does not match edge at end of bb %d", |
6de9cd9a DN |
3849 | bb->index); |
3850 | err = 1; | |
3851 | } | |
3852 | } | |
3853 | break; | |
3854 | ||
3855 | case GOTO_EXPR: | |
3856 | if (simple_goto_p (stmt)) | |
3857 | { | |
ab532386 | 3858 | error ("explicit goto at end of bb %d", bb->index); |
6531d1be | 3859 | err = 1; |
6de9cd9a DN |
3860 | } |
3861 | else | |
3862 | { | |
6531d1be | 3863 | /* FIXME. We should double check that the labels in the |
6de9cd9a | 3864 | destination blocks have their address taken. */ |
628f6a4e | 3865 | FOR_EACH_EDGE (e, ei, bb->succs) |
6de9cd9a DN |
3866 | if ((e->flags & (EDGE_FALLTHRU | EDGE_TRUE_VALUE |
3867 | | EDGE_FALSE_VALUE)) | |
3868 | || !(e->flags & EDGE_ABNORMAL)) | |
3869 | { | |
ab532386 | 3870 | error ("wrong outgoing edge flags at end of bb %d", |
6de9cd9a DN |
3871 | bb->index); |
3872 | err = 1; | |
3873 | } | |
3874 | } | |
3875 | break; | |
3876 | ||
3877 | case RETURN_EXPR: | |
c5cbcccf ZD |
3878 | if (!single_succ_p (bb) |
3879 | || (single_succ_edge (bb)->flags | |
3880 | & (EDGE_FALLTHRU | EDGE_ABNORMAL | |
3881 | | EDGE_TRUE_VALUE | EDGE_FALSE_VALUE))) | |
6de9cd9a | 3882 | { |
ab532386 | 3883 | error ("wrong outgoing edge flags at end of bb %d", bb->index); |
6de9cd9a DN |
3884 | err = 1; |
3885 | } | |
c5cbcccf | 3886 | if (single_succ (bb) != EXIT_BLOCK_PTR) |
6de9cd9a | 3887 | { |
ab532386 | 3888 | error ("return edge does not point to exit in bb %d", |
6de9cd9a DN |
3889 | bb->index); |
3890 | err = 1; | |
3891 | } | |
3892 | break; | |
3893 | ||
3894 | case SWITCH_EXPR: | |
3895 | { | |
7853504d | 3896 | tree prev; |
6de9cd9a DN |
3897 | edge e; |
3898 | size_t i, n; | |
3899 | tree vec; | |
3900 | ||
3901 | vec = SWITCH_LABELS (stmt); | |
3902 | n = TREE_VEC_LENGTH (vec); | |
3903 | ||
3904 | /* Mark all the destination basic blocks. */ | |
3905 | for (i = 0; i < n; ++i) | |
3906 | { | |
3907 | tree lab = CASE_LABEL (TREE_VEC_ELT (vec, i)); | |
3908 | basic_block label_bb = label_to_block (lab); | |
3909 | ||
1e128c5f | 3910 | gcc_assert (!label_bb->aux || label_bb->aux == (void *)1); |
6de9cd9a DN |
3911 | label_bb->aux = (void *)1; |
3912 | } | |
3913 | ||
7853504d SB |
3914 | /* Verify that the case labels are sorted. */ |
3915 | prev = TREE_VEC_ELT (vec, 0); | |
3916 | for (i = 1; i < n - 1; ++i) | |
3917 | { | |
3918 | tree c = TREE_VEC_ELT (vec, i); | |
3919 | if (! CASE_LOW (c)) | |
3920 | { | |
ab532386 | 3921 | error ("found default case not at end of case vector"); |
7853504d SB |
3922 | err = 1; |
3923 | continue; | |
3924 | } | |
3925 | if (! tree_int_cst_lt (CASE_LOW (prev), CASE_LOW (c))) | |
3926 | { | |
953ff289 | 3927 | error ("case labels not sorted: "); |
7853504d SB |
3928 | print_generic_expr (stderr, prev, 0); |
3929 | fprintf (stderr," is greater than "); | |
3930 | print_generic_expr (stderr, c, 0); | |
3931 | fprintf (stderr," but comes before it.\n"); | |
3932 | err = 1; | |
3933 | } | |
3934 | prev = c; | |
3935 | } | |
3936 | if (CASE_LOW (TREE_VEC_ELT (vec, n - 1))) | |
3937 | { | |
ab532386 | 3938 | error ("no default case found at end of case vector"); |
7853504d SB |
3939 | err = 1; |
3940 | } | |
3941 | ||
628f6a4e | 3942 | FOR_EACH_EDGE (e, ei, bb->succs) |
6de9cd9a DN |
3943 | { |
3944 | if (!e->dest->aux) | |
3945 | { | |
ab532386 | 3946 | error ("extra outgoing edge %d->%d", |
6de9cd9a DN |
3947 | bb->index, e->dest->index); |
3948 | err = 1; | |
3949 | } | |
3950 | e->dest->aux = (void *)2; | |
3951 | if ((e->flags & (EDGE_FALLTHRU | EDGE_ABNORMAL | |
3952 | | EDGE_TRUE_VALUE | EDGE_FALSE_VALUE))) | |
3953 | { | |
ab532386 | 3954 | error ("wrong outgoing edge flags at end of bb %d", |
6de9cd9a DN |
3955 | bb->index); |
3956 | err = 1; | |
3957 | } | |
3958 | } | |
3959 | ||
3960 | /* Check that we have all of them. */ | |
3961 | for (i = 0; i < n; ++i) | |
3962 | { | |
3963 | tree lab = CASE_LABEL (TREE_VEC_ELT (vec, i)); | |
3964 | basic_block label_bb = label_to_block (lab); | |
3965 | ||
3966 | if (label_bb->aux != (void *)2) | |
3967 | { | |
ab532386 | 3968 | error ("missing edge %i->%i", |
6de9cd9a DN |
3969 | bb->index, label_bb->index); |
3970 | err = 1; | |
3971 | } | |
3972 | } | |
3973 | ||
628f6a4e | 3974 | FOR_EACH_EDGE (e, ei, bb->succs) |
6de9cd9a DN |
3975 | e->dest->aux = (void *)0; |
3976 | } | |
3977 | ||
3978 | default: ; | |
3979 | } | |
3980 | } | |
3981 | ||
3982 | if (dom_computed[CDI_DOMINATORS] >= DOM_NO_FAST_QUERY) | |
3983 | verify_dominators (CDI_DOMINATORS); | |
3984 | ||
3985 | return err; | |
3986 | } | |
3987 | ||
3988 | ||
f0b698c1 | 3989 | /* Updates phi nodes after creating a forwarder block joined |
6de9cd9a DN |
3990 | by edge FALLTHRU. */ |
3991 | ||
3992 | static void | |
3993 | tree_make_forwarder_block (edge fallthru) | |
3994 | { | |
3995 | edge e; | |
628f6a4e | 3996 | edge_iterator ei; |
6de9cd9a | 3997 | basic_block dummy, bb; |
5ae71719 | 3998 | tree phi, new_phi, var; |
6de9cd9a DN |
3999 | |
4000 | dummy = fallthru->src; | |
4001 | bb = fallthru->dest; | |
4002 | ||
c5cbcccf | 4003 | if (single_pred_p (bb)) |
6de9cd9a DN |
4004 | return; |
4005 | ||
cfaab3a9 | 4006 | /* If we redirected a branch we must create new PHI nodes at the |
6de9cd9a | 4007 | start of BB. */ |
17192884 | 4008 | for (phi = phi_nodes (dummy); phi; phi = PHI_CHAIN (phi)) |
6de9cd9a DN |
4009 | { |
4010 | var = PHI_RESULT (phi); | |
4011 | new_phi = create_phi_node (var, bb); | |
4012 | SSA_NAME_DEF_STMT (var) = new_phi; | |
d00ad49b | 4013 | SET_PHI_RESULT (phi, make_ssa_name (SSA_NAME_VAR (var), phi)); |
d2e398df | 4014 | add_phi_arg (new_phi, PHI_RESULT (phi), fallthru); |
6de9cd9a DN |
4015 | } |
4016 | ||
17192884 | 4017 | /* Ensure that the PHI node chain is in the same order. */ |
5ae71719 | 4018 | set_phi_nodes (bb, phi_reverse (phi_nodes (bb))); |
6de9cd9a DN |
4019 | |
4020 | /* Add the arguments we have stored on edges. */ | |
628f6a4e | 4021 | FOR_EACH_EDGE (e, ei, bb->preds) |
6de9cd9a DN |
4022 | { |
4023 | if (e == fallthru) | |
4024 | continue; | |
4025 | ||
71882046 | 4026 | flush_pending_stmts (e); |
6de9cd9a DN |
4027 | } |
4028 | } | |
4029 | ||
4030 | ||
6de9cd9a DN |
4031 | /* Return a non-special label in the head of basic block BLOCK. |
4032 | Create one if it doesn't exist. */ | |
4033 | ||
d7621d3c | 4034 | tree |
6de9cd9a DN |
4035 | tree_block_label (basic_block bb) |
4036 | { | |
4037 | block_stmt_iterator i, s = bsi_start (bb); | |
4038 | bool first = true; | |
4039 | tree label, stmt; | |
4040 | ||
4041 | for (i = s; !bsi_end_p (i); first = false, bsi_next (&i)) | |
4042 | { | |
4043 | stmt = bsi_stmt (i); | |
4044 | if (TREE_CODE (stmt) != LABEL_EXPR) | |
4045 | break; | |
4046 | label = LABEL_EXPR_LABEL (stmt); | |
4047 | if (!DECL_NONLOCAL (label)) | |
4048 | { | |
4049 | if (!first) | |
4050 | bsi_move_before (&i, &s); | |
4051 | return label; | |
4052 | } | |
4053 | } | |
4054 | ||
4055 | label = create_artificial_label (); | |
4056 | stmt = build1 (LABEL_EXPR, void_type_node, label); | |
4057 | bsi_insert_before (&s, stmt, BSI_NEW_STMT); | |
4058 | return label; | |
4059 | } | |
4060 | ||
4061 | ||
4062 | /* Attempt to perform edge redirection by replacing a possibly complex | |
4063 | jump instruction by a goto or by removing the jump completely. | |
4064 | This can apply only if all edges now point to the same block. The | |
4065 | parameters and return values are equivalent to | |
4066 | redirect_edge_and_branch. */ | |
4067 | ||
4068 | static edge | |
4069 | tree_try_redirect_by_replacing_jump (edge e, basic_block target) | |
4070 | { | |
4071 | basic_block src = e->src; | |
6de9cd9a DN |
4072 | block_stmt_iterator b; |
4073 | tree stmt; | |
6de9cd9a | 4074 | |
07b43a87 KH |
4075 | /* We can replace or remove a complex jump only when we have exactly |
4076 | two edges. */ | |
4077 | if (EDGE_COUNT (src->succs) != 2 | |
4078 | /* Verify that all targets will be TARGET. Specifically, the | |
4079 | edge that is not E must also go to TARGET. */ | |
4080 | || EDGE_SUCC (src, EDGE_SUCC (src, 0) == e)->dest != target) | |
6de9cd9a DN |
4081 | return NULL; |
4082 | ||
4083 | b = bsi_last (src); | |
4084 | if (bsi_end_p (b)) | |
4085 | return NULL; | |
4086 | stmt = bsi_stmt (b); | |
4087 | ||
4088 | if (TREE_CODE (stmt) == COND_EXPR | |
4089 | || TREE_CODE (stmt) == SWITCH_EXPR) | |
4090 | { | |
736432ee | 4091 | bsi_remove (&b, true); |
6de9cd9a DN |
4092 | e = ssa_redirect_edge (e, target); |
4093 | e->flags = EDGE_FALLTHRU; | |
4094 | return e; | |
4095 | } | |
4096 | ||
4097 | return NULL; | |
4098 | } | |
4099 | ||
4100 | ||
4101 | /* Redirect E to DEST. Return NULL on failure. Otherwise, return the | |
4102 | edge representing the redirected branch. */ | |
4103 | ||
4104 | static edge | |
4105 | tree_redirect_edge_and_branch (edge e, basic_block dest) | |
4106 | { | |
4107 | basic_block bb = e->src; | |
4108 | block_stmt_iterator bsi; | |
4109 | edge ret; | |
4110 | tree label, stmt; | |
4111 | ||
4f6c2131 | 4112 | if (e->flags & EDGE_ABNORMAL) |
6de9cd9a DN |
4113 | return NULL; |
4114 | ||
6531d1be | 4115 | if (e->src != ENTRY_BLOCK_PTR |
6de9cd9a DN |
4116 | && (ret = tree_try_redirect_by_replacing_jump (e, dest))) |
4117 | return ret; | |
4118 | ||
4119 | if (e->dest == dest) | |
4120 | return NULL; | |
4121 | ||
4122 | label = tree_block_label (dest); | |
4123 | ||
4124 | bsi = bsi_last (bb); | |
4125 | stmt = bsi_end_p (bsi) ? NULL : bsi_stmt (bsi); | |
4126 | ||
4127 | switch (stmt ? TREE_CODE (stmt) : ERROR_MARK) | |
4128 | { | |
4129 | case COND_EXPR: | |
4130 | stmt = (e->flags & EDGE_TRUE_VALUE | |
4131 | ? COND_EXPR_THEN (stmt) | |
4132 | : COND_EXPR_ELSE (stmt)); | |
4133 | GOTO_DESTINATION (stmt) = label; | |
4134 | break; | |
4135 | ||
4136 | case GOTO_EXPR: | |
4137 | /* No non-abnormal edges should lead from a non-simple goto, and | |
4138 | simple ones should be represented implicitly. */ | |
1e128c5f | 4139 | gcc_unreachable (); |
6de9cd9a DN |
4140 | |
4141 | case SWITCH_EXPR: | |
4142 | { | |
d6be0d7f | 4143 | tree cases = get_cases_for_edge (e, stmt); |
6de9cd9a | 4144 | |
d6be0d7f JL |
4145 | /* If we have a list of cases associated with E, then use it |
4146 | as it's a lot faster than walking the entire case vector. */ | |
4147 | if (cases) | |
6de9cd9a | 4148 | { |
4edbbd3f | 4149 | edge e2 = find_edge (e->src, dest); |
d6be0d7f JL |
4150 | tree last, first; |
4151 | ||
4152 | first = cases; | |
4153 | while (cases) | |
4154 | { | |
4155 | last = cases; | |
4156 | CASE_LABEL (cases) = label; | |
4157 | cases = TREE_CHAIN (cases); | |
4158 | } | |
4159 | ||
4160 | /* If there was already an edge in the CFG, then we need | |
4161 | to move all the cases associated with E to E2. */ | |
4162 | if (e2) | |
4163 | { | |
4164 | tree cases2 = get_cases_for_edge (e2, stmt); | |
4165 | ||
4166 | TREE_CHAIN (last) = TREE_CHAIN (cases2); | |
4167 | TREE_CHAIN (cases2) = first; | |
4168 | } | |
6de9cd9a | 4169 | } |
92b6dff3 JL |
4170 | else |
4171 | { | |
d6be0d7f JL |
4172 | tree vec = SWITCH_LABELS (stmt); |
4173 | size_t i, n = TREE_VEC_LENGTH (vec); | |
4174 | ||
4175 | for (i = 0; i < n; i++) | |
4176 | { | |
4177 | tree elt = TREE_VEC_ELT (vec, i); | |
4178 | ||
4179 | if (label_to_block (CASE_LABEL (elt)) == e->dest) | |
4180 | CASE_LABEL (elt) = label; | |
4181 | } | |
92b6dff3 | 4182 | } |
d6be0d7f | 4183 | |
92b6dff3 | 4184 | break; |
6de9cd9a | 4185 | } |
6de9cd9a DN |
4186 | |
4187 | case RETURN_EXPR: | |
736432ee | 4188 | bsi_remove (&bsi, true); |
6de9cd9a DN |
4189 | e->flags |= EDGE_FALLTHRU; |
4190 | break; | |
4191 | ||
4192 | default: | |
4193 | /* Otherwise it must be a fallthru edge, and we don't need to | |
4194 | do anything besides redirecting it. */ | |
1e128c5f | 4195 | gcc_assert (e->flags & EDGE_FALLTHRU); |
6de9cd9a DN |
4196 | break; |
4197 | } | |
4198 | ||
4199 | /* Update/insert PHI nodes as necessary. */ | |
4200 | ||
4201 | /* Now update the edges in the CFG. */ | |
4202 | e = ssa_redirect_edge (e, dest); | |
4203 | ||
4204 | return e; | |
4205 | } | |
4206 | ||
4207 | ||
4208 | /* Simple wrapper, as we can always redirect fallthru edges. */ | |
4209 | ||
4210 | static basic_block | |
4211 | tree_redirect_edge_and_branch_force (edge e, basic_block dest) | |
4212 | { | |
4213 | e = tree_redirect_edge_and_branch (e, dest); | |
1e128c5f | 4214 | gcc_assert (e); |
6de9cd9a DN |
4215 | |
4216 | return NULL; | |
4217 | } | |
4218 | ||
4219 | ||
4220 | /* Splits basic block BB after statement STMT (but at least after the | |
4221 | labels). If STMT is NULL, BB is split just after the labels. */ | |
4222 | ||
4223 | static basic_block | |
4224 | tree_split_block (basic_block bb, void *stmt) | |
4225 | { | |
597ae074 JH |
4226 | block_stmt_iterator bsi; |
4227 | tree_stmt_iterator tsi_tgt; | |
6de9cd9a DN |
4228 | tree act; |
4229 | basic_block new_bb; | |
4230 | edge e; | |
628f6a4e | 4231 | edge_iterator ei; |
6de9cd9a DN |
4232 | |
4233 | new_bb = create_empty_bb (bb); | |
4234 | ||
4235 | /* Redirect the outgoing edges. */ | |
628f6a4e BE |
4236 | new_bb->succs = bb->succs; |
4237 | bb->succs = NULL; | |
4238 | FOR_EACH_EDGE (e, ei, new_bb->succs) | |
6de9cd9a DN |
4239 | e->src = new_bb; |
4240 | ||
4241 | if (stmt && TREE_CODE ((tree) stmt) == LABEL_EXPR) | |
4242 | stmt = NULL; | |
4243 | ||
4244 | /* Move everything from BSI to the new basic block. */ | |
4245 | for (bsi = bsi_start (bb); !bsi_end_p (bsi); bsi_next (&bsi)) | |
4246 | { | |
4247 | act = bsi_stmt (bsi); | |
4248 | if (TREE_CODE (act) == LABEL_EXPR) | |
4249 | continue; | |
4250 | ||
4251 | if (!stmt) | |
4252 | break; | |
4253 | ||
4254 | if (stmt == act) | |
4255 | { | |
4256 | bsi_next (&bsi); | |
4257 | break; | |
4258 | } | |
4259 | } | |
4260 | ||
597ae074 JH |
4261 | if (bsi_end_p (bsi)) |
4262 | return new_bb; | |
4263 | ||
4264 | /* Split the statement list - avoid re-creating new containers as this | |
4265 | brings ugly quadratic memory consumption in the inliner. | |
4266 | (We are still quadratic since we need to update stmt BB pointers, | |
4267 | sadly.) */ | |
4268 | new_bb->stmt_list = tsi_split_statement_list_before (&bsi.tsi); | |
4269 | for (tsi_tgt = tsi_start (new_bb->stmt_list); | |
4270 | !tsi_end_p (tsi_tgt); tsi_next (&tsi_tgt)) | |
0a4fe58f | 4271 | change_bb_for_stmt (tsi_stmt (tsi_tgt), new_bb); |
6de9cd9a DN |
4272 | |
4273 | return new_bb; | |
4274 | } | |
4275 | ||
4276 | ||
4277 | /* Moves basic block BB after block AFTER. */ | |
4278 | ||
4279 | static bool | |
4280 | tree_move_block_after (basic_block bb, basic_block after) | |
4281 | { | |
4282 | if (bb->prev_bb == after) | |
4283 | return true; | |
4284 | ||
4285 | unlink_block (bb); | |
4286 | link_block (bb, after); | |
4287 | ||
4288 | return true; | |
4289 | } | |
4290 | ||
4291 | ||
4292 | /* Return true if basic_block can be duplicated. */ | |
4293 | ||
4294 | static bool | |
4295 | tree_can_duplicate_bb_p (basic_block bb ATTRIBUTE_UNUSED) | |
4296 | { | |
4297 | return true; | |
4298 | } | |
4299 | ||
84d65814 | 4300 | |
6de9cd9a DN |
4301 | /* Create a duplicate of the basic block BB. NOTE: This does not |
4302 | preserve SSA form. */ | |
4303 | ||
4304 | static basic_block | |
4305 | tree_duplicate_bb (basic_block bb) | |
4306 | { | |
4307 | basic_block new_bb; | |
4308 | block_stmt_iterator bsi, bsi_tgt; | |
84d65814 | 4309 | tree phi; |
6de9cd9a DN |
4310 | |
4311 | new_bb = create_empty_bb (EXIT_BLOCK_PTR->prev_bb); | |
b0382c67 | 4312 | |
84d65814 DN |
4313 | /* Copy the PHI nodes. We ignore PHI node arguments here because |
4314 | the incoming edges have not been setup yet. */ | |
bb29d951 | 4315 | for (phi = phi_nodes (bb); phi; phi = PHI_CHAIN (phi)) |
b0382c67 | 4316 | { |
84d65814 DN |
4317 | tree copy = create_phi_node (PHI_RESULT (phi), new_bb); |
4318 | create_new_def_for (PHI_RESULT (copy), copy, PHI_RESULT_PTR (copy)); | |
b0382c67 | 4319 | } |
84d65814 DN |
4320 | |
4321 | /* Keep the chain of PHI nodes in the same order so that they can be | |
4322 | updated by ssa_redirect_edge. */ | |
5ae71719 | 4323 | set_phi_nodes (new_bb, phi_reverse (phi_nodes (new_bb))); |
b0382c67 | 4324 | |
6de9cd9a DN |
4325 | bsi_tgt = bsi_start (new_bb); |
4326 | for (bsi = bsi_start (bb); !bsi_end_p (bsi); bsi_next (&bsi)) | |
4327 | { | |
84d65814 DN |
4328 | def_operand_p def_p; |
4329 | ssa_op_iter op_iter; | |
4330 | tree stmt, copy; | |
cc7220fd | 4331 | int region; |
6de9cd9a | 4332 | |
84d65814 | 4333 | stmt = bsi_stmt (bsi); |
6de9cd9a DN |
4334 | if (TREE_CODE (stmt) == LABEL_EXPR) |
4335 | continue; | |
4336 | ||
84d65814 DN |
4337 | /* Create a new copy of STMT and duplicate STMT's virtual |
4338 | operands. */ | |
5f240ec4 | 4339 | copy = unshare_expr (stmt); |
5f240ec4 | 4340 | bsi_insert_after (&bsi_tgt, copy, BSI_NEW_STMT); |
84d65814 | 4341 | copy_virtual_operands (copy, stmt); |
cc7220fd JH |
4342 | region = lookup_stmt_eh_region (stmt); |
4343 | if (region >= 0) | |
4344 | add_stmt_to_eh_region (copy, region); | |
84d65814 DN |
4345 | |
4346 | /* Create new names for all the definitions created by COPY and | |
4347 | add replacement mappings for each new name. */ | |
4348 | FOR_EACH_SSA_DEF_OPERAND (def_p, copy, op_iter, SSA_OP_ALL_DEFS) | |
4349 | create_new_def_for (DEF_FROM_PTR (def_p), copy, def_p); | |
6de9cd9a DN |
4350 | } |
4351 | ||
4352 | return new_bb; | |
4353 | } | |
4354 | ||
84d65814 | 4355 | |
42759f1e ZD |
4356 | /* Basic block BB_COPY was created by code duplication. Add phi node |
4357 | arguments for edges going out of BB_COPY. The blocks that were | |
6580ee77 | 4358 | duplicated have BB_DUPLICATED set. */ |
42759f1e ZD |
4359 | |
4360 | void | |
4361 | add_phi_args_after_copy_bb (basic_block bb_copy) | |
4362 | { | |
4363 | basic_block bb, dest; | |
4364 | edge e, e_copy; | |
628f6a4e | 4365 | edge_iterator ei; |
42759f1e | 4366 | tree phi, phi_copy, phi_next, def; |
6531d1be | 4367 | |
6580ee77 | 4368 | bb = get_bb_original (bb_copy); |
42759f1e | 4369 | |
628f6a4e | 4370 | FOR_EACH_EDGE (e_copy, ei, bb_copy->succs) |
42759f1e ZD |
4371 | { |
4372 | if (!phi_nodes (e_copy->dest)) | |
4373 | continue; | |
4374 | ||
6580ee77 JH |
4375 | if (e_copy->dest->flags & BB_DUPLICATED) |
4376 | dest = get_bb_original (e_copy->dest); | |
42759f1e ZD |
4377 | else |
4378 | dest = e_copy->dest; | |
4379 | ||
4380 | e = find_edge (bb, dest); | |
4381 | if (!e) | |
4382 | { | |
4383 | /* During loop unrolling the target of the latch edge is copied. | |
4384 | In this case we are not looking for edge to dest, but to | |
4385 | duplicated block whose original was dest. */ | |
628f6a4e | 4386 | FOR_EACH_EDGE (e, ei, bb->succs) |
6580ee77 JH |
4387 | if ((e->dest->flags & BB_DUPLICATED) |
4388 | && get_bb_original (e->dest) == dest) | |
42759f1e ZD |
4389 | break; |
4390 | ||
4391 | gcc_assert (e != NULL); | |
4392 | } | |
4393 | ||
4394 | for (phi = phi_nodes (e->dest), phi_copy = phi_nodes (e_copy->dest); | |
4395 | phi; | |
eaf0dc02 | 4396 | phi = phi_next, phi_copy = PHI_CHAIN (phi_copy)) |
42759f1e | 4397 | { |
eaf0dc02 | 4398 | phi_next = PHI_CHAIN (phi); |
42759f1e | 4399 | def = PHI_ARG_DEF_FROM_EDGE (phi, e); |
d2e398df | 4400 | add_phi_arg (phi_copy, def, e_copy); |
42759f1e ZD |
4401 | } |
4402 | } | |
4403 | } | |
4404 | ||
4405 | /* Blocks in REGION_COPY array of length N_REGION were created by | |
4406 | duplication of basic blocks. Add phi node arguments for edges | |
4407 | going from these blocks. */ | |
4408 | ||
4409 | void | |
4410 | add_phi_args_after_copy (basic_block *region_copy, unsigned n_region) | |
4411 | { | |
4412 | unsigned i; | |
4413 | ||
4414 | for (i = 0; i < n_region; i++) | |
6580ee77 | 4415 | region_copy[i]->flags |= BB_DUPLICATED; |
42759f1e ZD |
4416 | |
4417 | for (i = 0; i < n_region; i++) | |
4418 | add_phi_args_after_copy_bb (region_copy[i]); | |
4419 | ||
4420 | for (i = 0; i < n_region; i++) | |
6580ee77 | 4421 | region_copy[i]->flags &= ~BB_DUPLICATED; |
42759f1e ZD |
4422 | } |
4423 | ||
42759f1e ZD |
4424 | /* Duplicates a REGION (set of N_REGION basic blocks) with just a single |
4425 | important exit edge EXIT. By important we mean that no SSA name defined | |
4426 | inside region is live over the other exit edges of the region. All entry | |
4427 | edges to the region must go to ENTRY->dest. The edge ENTRY is redirected | |
4428 | to the duplicate of the region. SSA form, dominance and loop information | |
4429 | is updated. The new basic blocks are stored to REGION_COPY in the same | |
4430 | order as they had in REGION, provided that REGION_COPY is not NULL. | |
4431 | The function returns false if it is unable to copy the region, | |
4432 | true otherwise. */ | |
4433 | ||
4434 | bool | |
4435 | tree_duplicate_sese_region (edge entry, edge exit, | |
4436 | basic_block *region, unsigned n_region, | |
4437 | basic_block *region_copy) | |
4438 | { | |
84d65814 | 4439 | unsigned i, n_doms; |
42759f1e ZD |
4440 | bool free_region_copy = false, copying_header = false; |
4441 | struct loop *loop = entry->dest->loop_father; | |
4442 | edge exit_copy; | |
42759f1e | 4443 | basic_block *doms; |
42759f1e | 4444 | edge redirected; |
09bac500 JH |
4445 | int total_freq = 0, entry_freq = 0; |
4446 | gcov_type total_count = 0, entry_count = 0; | |
42759f1e ZD |
4447 | |
4448 | if (!can_copy_bbs_p (region, n_region)) | |
4449 | return false; | |
4450 | ||
4451 | /* Some sanity checking. Note that we do not check for all possible | |
4452 | missuses of the functions. I.e. if you ask to copy something weird, | |
4453 | it will work, but the state of structures probably will not be | |
4454 | correct. */ | |
42759f1e ZD |
4455 | for (i = 0; i < n_region; i++) |
4456 | { | |
4457 | /* We do not handle subloops, i.e. all the blocks must belong to the | |
4458 | same loop. */ | |
4459 | if (region[i]->loop_father != loop) | |
4460 | return false; | |
4461 | ||
4462 | if (region[i] != entry->dest | |
4463 | && region[i] == loop->header) | |
4464 | return false; | |
4465 | } | |
4466 | ||
4467 | loop->copy = loop; | |
4468 | ||
4469 | /* In case the function is used for loop header copying (which is the primary | |
4470 | use), ensure that EXIT and its copy will be new latch and entry edges. */ | |
4471 | if (loop->header == entry->dest) | |
4472 | { | |
4473 | copying_header = true; | |
4474 | loop->copy = loop->outer; | |
4475 | ||
4476 | if (!dominated_by_p (CDI_DOMINATORS, loop->latch, exit->src)) | |
4477 | return false; | |
4478 | ||
4479 | for (i = 0; i < n_region; i++) | |
4480 | if (region[i] != exit->src | |
4481 | && dominated_by_p (CDI_DOMINATORS, region[i], exit->src)) | |
4482 | return false; | |
4483 | } | |
4484 | ||
4485 | if (!region_copy) | |
4486 | { | |
858904db | 4487 | region_copy = XNEWVEC (basic_block, n_region); |
42759f1e ZD |
4488 | free_region_copy = true; |
4489 | } | |
4490 | ||
84d65814 | 4491 | gcc_assert (!need_ssa_update_p ()); |
42759f1e | 4492 | |
5deaef19 | 4493 | /* Record blocks outside the region that are dominated by something |
42759f1e | 4494 | inside. */ |
858904db | 4495 | doms = XNEWVEC (basic_block, n_basic_blocks); |
6580ee77 JH |
4496 | initialize_original_copy_tables (); |
4497 | ||
42759f1e ZD |
4498 | n_doms = get_dominated_by_region (CDI_DOMINATORS, region, n_region, doms); |
4499 | ||
09bac500 JH |
4500 | if (entry->dest->count) |
4501 | { | |
4502 | total_count = entry->dest->count; | |
4503 | entry_count = entry->count; | |
4504 | /* Fix up corner cases, to avoid division by zero or creation of negative | |
4505 | frequencies. */ | |
4506 | if (entry_count > total_count) | |
4507 | entry_count = total_count; | |
4508 | } | |
4509 | else | |
4510 | { | |
4511 | total_freq = entry->dest->frequency; | |
4512 | entry_freq = EDGE_FREQUENCY (entry); | |
4513 | /* Fix up corner cases, to avoid division by zero or creation of negative | |
4514 | frequencies. */ | |
4515 | if (total_freq == 0) | |
4516 | total_freq = 1; | |
4517 | else if (entry_freq > total_freq) | |
4518 | entry_freq = total_freq; | |
4519 | } | |
5deaef19 | 4520 | |
b9a66240 ZD |
4521 | copy_bbs (region, n_region, region_copy, &exit, 1, &exit_copy, loop, |
4522 | split_edge_bb_loc (entry)); | |
09bac500 JH |
4523 | if (total_count) |
4524 | { | |
4525 | scale_bbs_frequencies_gcov_type (region, n_region, | |
4526 | total_count - entry_count, | |
4527 | total_count); | |
4528 | scale_bbs_frequencies_gcov_type (region_copy, n_region, entry_count, | |
6531d1be | 4529 | total_count); |
09bac500 JH |
4530 | } |
4531 | else | |
4532 | { | |
4533 | scale_bbs_frequencies_int (region, n_region, total_freq - entry_freq, | |
4534 | total_freq); | |
4535 | scale_bbs_frequencies_int (region_copy, n_region, entry_freq, total_freq); | |
4536 | } | |
42759f1e ZD |
4537 | |
4538 | if (copying_header) | |
4539 | { | |
4540 | loop->header = exit->dest; | |
4541 | loop->latch = exit->src; | |
4542 | } | |
4543 | ||
4544 | /* Redirect the entry and add the phi node arguments. */ | |
6580ee77 | 4545 | redirected = redirect_edge_and_branch (entry, get_bb_copy (entry->dest)); |
42759f1e | 4546 | gcc_assert (redirected != NULL); |
71882046 | 4547 | flush_pending_stmts (entry); |
42759f1e ZD |
4548 | |
4549 | /* Concerning updating of dominators: We must recount dominators | |
84d65814 DN |
4550 | for entry block and its copy. Anything that is outside of the |
4551 | region, but was dominated by something inside needs recounting as | |
4552 | well. */ | |
42759f1e | 4553 | set_immediate_dominator (CDI_DOMINATORS, entry->dest, entry->src); |
6580ee77 | 4554 | doms[n_doms++] = get_bb_original (entry->dest); |
42759f1e ZD |
4555 | iterate_fix_dominators (CDI_DOMINATORS, doms, n_doms); |
4556 | free (doms); | |
4557 | ||
84d65814 | 4558 | /* Add the other PHI node arguments. */ |
42759f1e ZD |
4559 | add_phi_args_after_copy (region_copy, n_region); |
4560 | ||
84d65814 DN |
4561 | /* Update the SSA web. */ |
4562 | update_ssa (TODO_update_ssa); | |
42759f1e ZD |
4563 | |
4564 | if (free_region_copy) | |
4565 | free (region_copy); | |
4566 | ||
6580ee77 | 4567 | free_original_copy_tables (); |
42759f1e ZD |
4568 | return true; |
4569 | } | |
6de9cd9a | 4570 | |
50674e96 DN |
4571 | /* |
4572 | DEF_VEC_P(basic_block); | |
4573 | DEF_VEC_ALLOC_P(basic_block,heap); | |
4574 | */ | |
4575 | ||
4576 | /* Add all the blocks dominated by ENTRY to the array BBS_P. Stop | |
4577 | adding blocks when the dominator traversal reaches EXIT. This | |
4578 | function silently assumes that ENTRY strictly dominates EXIT. */ | |
4579 | ||
4580 | static void | |
4581 | gather_blocks_in_sese_region (basic_block entry, basic_block exit, | |
4582 | VEC(basic_block,heap) **bbs_p) | |
4583 | { | |
4584 | basic_block son; | |
4585 | ||
4586 | for (son = first_dom_son (CDI_DOMINATORS, entry); | |
4587 | son; | |
4588 | son = next_dom_son (CDI_DOMINATORS, son)) | |
4589 | { | |
4590 | VEC_safe_push (basic_block, heap, *bbs_p, son); | |
4591 | if (son != exit) | |
4592 | gather_blocks_in_sese_region (son, exit, bbs_p); | |
4593 | } | |
4594 | } | |
4595 | ||
4596 | ||
4597 | struct move_stmt_d | |
4598 | { | |
4599 | tree block; | |
4600 | tree from_context; | |
4601 | tree to_context; | |
4602 | bitmap vars_to_remove; | |
fad41cd7 | 4603 | htab_t new_label_map; |
50674e96 DN |
4604 | bool remap_decls_p; |
4605 | }; | |
4606 | ||
4607 | /* Helper for move_block_to_fn. Set TREE_BLOCK in every expression | |
4608 | contained in *TP and change the DECL_CONTEXT of every local | |
4609 | variable referenced in *TP. */ | |
4610 | ||
4611 | static tree | |
fad41cd7 | 4612 | move_stmt_r (tree *tp, int *walk_subtrees, void *data) |
50674e96 DN |
4613 | { |
4614 | struct move_stmt_d *p = (struct move_stmt_d *) data; | |
fad41cd7 | 4615 | tree t = *tp; |
50674e96 | 4616 | |
07beea0d AH |
4617 | if (p->block |
4618 | && (EXPR_P (t) || GIMPLE_STMT_P (t))) | |
fad41cd7 | 4619 | TREE_BLOCK (t) = p->block; |
50674e96 | 4620 | |
bed575d5 RS |
4621 | if (OMP_DIRECTIVE_P (t) |
4622 | && TREE_CODE (t) != OMP_RETURN | |
4623 | && TREE_CODE (t) != OMP_CONTINUE) | |
50674e96 DN |
4624 | { |
4625 | /* Do not remap variables inside OMP directives. Variables | |
4626 | referenced in clauses and directive header belong to the | |
4627 | parent function and should not be moved into the child | |
4628 | function. */ | |
fad41cd7 | 4629 | bool save_remap_decls_p = p->remap_decls_p; |
50674e96 | 4630 | p->remap_decls_p = false; |
fad41cd7 RH |
4631 | *walk_subtrees = 0; |
4632 | ||
4633 | walk_tree (&OMP_BODY (t), move_stmt_r, p, NULL); | |
50674e96 | 4634 | |
fad41cd7 RH |
4635 | p->remap_decls_p = save_remap_decls_p; |
4636 | } | |
4637 | else if (DECL_P (t) && DECL_CONTEXT (t) == p->from_context) | |
50674e96 | 4638 | { |
fad41cd7 RH |
4639 | if (TREE_CODE (t) == LABEL_DECL) |
4640 | { | |
4641 | if (p->new_label_map) | |
4642 | { | |
4643 | struct tree_map in, *out; | |
4644 | in.from = t; | |
4645 | out = htab_find_with_hash (p->new_label_map, &in, DECL_UID (t)); | |
4646 | if (out) | |
4647 | *tp = t = out->to; | |
4648 | } | |
50674e96 | 4649 | |
fad41cd7 RH |
4650 | DECL_CONTEXT (t) = p->to_context; |
4651 | } | |
4652 | else if (p->remap_decls_p) | |
50674e96 | 4653 | { |
fad41cd7 | 4654 | DECL_CONTEXT (t) = p->to_context; |
50674e96 | 4655 | |
fad41cd7 RH |
4656 | if (TREE_CODE (t) == VAR_DECL) |
4657 | { | |
4658 | struct function *f = DECL_STRUCT_FUNCTION (p->to_context); | |
4659 | f->unexpanded_var_list | |
4660 | = tree_cons (0, t, f->unexpanded_var_list); | |
4661 | ||
4662 | /* Mark T to be removed from the original function, | |
4663 | otherwise it will be given a DECL_RTL when the | |
4664 | original function is expanded. */ | |
4665 | bitmap_set_bit (p->vars_to_remove, DECL_UID (t)); | |
4666 | } | |
50674e96 DN |
4667 | } |
4668 | } | |
fad41cd7 RH |
4669 | else if (TYPE_P (t)) |
4670 | *walk_subtrees = 0; | |
50674e96 DN |
4671 | |
4672 | return NULL_TREE; | |
4673 | } | |
4674 | ||
4675 | ||
4676 | /* Move basic block BB from function CFUN to function DEST_FN. The | |
4677 | block is moved out of the original linked list and placed after | |
4678 | block AFTER in the new list. Also, the block is removed from the | |
4679 | original array of blocks and placed in DEST_FN's array of blocks. | |
4680 | If UPDATE_EDGE_COUNT_P is true, the edge counts on both CFGs is | |
4681 | updated to reflect the moved edges. | |
6531d1be | 4682 | |
50674e96 DN |
4683 | On exit, local variables that need to be removed from |
4684 | CFUN->UNEXPANDED_VAR_LIST will have been added to VARS_TO_REMOVE. */ | |
4685 | ||
4686 | static void | |
4687 | move_block_to_fn (struct function *dest_cfun, basic_block bb, | |
4688 | basic_block after, bool update_edge_count_p, | |
fad41cd7 | 4689 | bitmap vars_to_remove, htab_t new_label_map, int eh_offset) |
50674e96 DN |
4690 | { |
4691 | struct control_flow_graph *cfg; | |
4692 | edge_iterator ei; | |
4693 | edge e; | |
4694 | block_stmt_iterator si; | |
4695 | struct move_stmt_d d; | |
728b26bb DN |
4696 | unsigned old_len, new_len; |
4697 | basic_block *addr; | |
50674e96 DN |
4698 | |
4699 | /* Link BB to the new linked list. */ | |
4700 | move_block_after (bb, after); | |
4701 | ||
4702 | /* Update the edge count in the corresponding flowgraphs. */ | |
4703 | if (update_edge_count_p) | |
4704 | FOR_EACH_EDGE (e, ei, bb->succs) | |
4705 | { | |
4706 | cfun->cfg->x_n_edges--; | |
4707 | dest_cfun->cfg->x_n_edges++; | |
4708 | } | |
4709 | ||
4710 | /* Remove BB from the original basic block array. */ | |
4711 | VEC_replace (basic_block, cfun->cfg->x_basic_block_info, bb->index, NULL); | |
4712 | cfun->cfg->x_n_basic_blocks--; | |
4713 | ||
4714 | /* Grow DEST_CFUN's basic block array if needed. */ | |
4715 | cfg = dest_cfun->cfg; | |
4716 | cfg->x_n_basic_blocks++; | |
4717 | if (bb->index > cfg->x_last_basic_block) | |
4718 | cfg->x_last_basic_block = bb->index; | |
4719 | ||
728b26bb DN |
4720 | old_len = VEC_length (basic_block, cfg->x_basic_block_info); |
4721 | if ((unsigned) cfg->x_last_basic_block >= old_len) | |
50674e96 | 4722 | { |
728b26bb DN |
4723 | new_len = cfg->x_last_basic_block + (cfg->x_last_basic_block + 3) / 4; |
4724 | VEC_safe_grow (basic_block, gc, cfg->x_basic_block_info, new_len); | |
4725 | addr = VEC_address (basic_block, cfg->x_basic_block_info); | |
4726 | memset (&addr[old_len], 0, sizeof (basic_block) * (new_len - old_len)); | |
50674e96 DN |
4727 | } |
4728 | ||
4729 | VEC_replace (basic_block, cfg->x_basic_block_info, | |
4730 | cfg->x_last_basic_block, bb); | |
4731 | ||
4732 | /* The statements in BB need to be associated with a new TREE_BLOCK. | |
4733 | Labels need to be associated with a new label-to-block map. */ | |
4734 | memset (&d, 0, sizeof (d)); | |
4735 | d.vars_to_remove = vars_to_remove; | |
4736 | ||
4737 | for (si = bsi_start (bb); !bsi_end_p (si); bsi_next (&si)) | |
4738 | { | |
4739 | tree stmt = bsi_stmt (si); | |
fad41cd7 | 4740 | int region; |
50674e96 DN |
4741 | |
4742 | d.from_context = cfun->decl; | |
4743 | d.to_context = dest_cfun->decl; | |
4744 | d.remap_decls_p = true; | |
fad41cd7 | 4745 | d.new_label_map = new_label_map; |
50674e96 DN |
4746 | if (TREE_BLOCK (stmt)) |
4747 | d.block = DECL_INITIAL (dest_cfun->decl); | |
4748 | ||
4749 | walk_tree (&stmt, move_stmt_r, &d, NULL); | |
4750 | ||
4751 | if (TREE_CODE (stmt) == LABEL_EXPR) | |
4752 | { | |
50674e96 DN |
4753 | tree label = LABEL_EXPR_LABEL (stmt); |
4754 | int uid = LABEL_DECL_UID (label); | |
4755 | ||
4756 | gcc_assert (uid > -1); | |
4757 | ||
4758 | old_len = VEC_length (basic_block, cfg->x_label_to_block_map); | |
4759 | if (old_len <= (unsigned) uid) | |
4760 | { | |
728b26bb | 4761 | new_len = 3 * uid / 2; |
50674e96 DN |
4762 | VEC_safe_grow (basic_block, gc, cfg->x_label_to_block_map, |
4763 | new_len); | |
4764 | addr = VEC_address (basic_block, cfg->x_label_to_block_map); | |
4765 | memset (&addr[old_len], 0, | |
4766 | sizeof (basic_block) * (new_len - old_len)); | |
4767 | } | |
4768 | ||
4769 | VEC_replace (basic_block, cfg->x_label_to_block_map, uid, bb); | |
4770 | VEC_replace (basic_block, cfun->cfg->x_label_to_block_map, uid, NULL); | |
4771 | ||
4772 | gcc_assert (DECL_CONTEXT (label) == dest_cfun->decl); | |
4773 | ||
4774 | if (uid >= dest_cfun->last_label_uid) | |
4775 | dest_cfun->last_label_uid = uid + 1; | |
4776 | } | |
fad41cd7 RH |
4777 | else if (TREE_CODE (stmt) == RESX_EXPR && eh_offset != 0) |
4778 | TREE_OPERAND (stmt, 0) = | |
4779 | build_int_cst (NULL_TREE, | |
4780 | TREE_INT_CST_LOW (TREE_OPERAND (stmt, 0)) | |
4781 | + eh_offset); | |
4782 | ||
4783 | region = lookup_stmt_eh_region (stmt); | |
4784 | if (region >= 0) | |
4785 | { | |
4786 | add_stmt_to_eh_region_fn (dest_cfun, stmt, region + eh_offset); | |
4787 | remove_stmt_from_eh_region (stmt); | |
4788 | } | |
4789 | } | |
4790 | } | |
4791 | ||
4792 | /* Examine the statements in BB (which is in SRC_CFUN); find and return | |
4793 | the outermost EH region. Use REGION as the incoming base EH region. */ | |
4794 | ||
4795 | static int | |
4796 | find_outermost_region_in_block (struct function *src_cfun, | |
4797 | basic_block bb, int region) | |
4798 | { | |
4799 | block_stmt_iterator si; | |
6531d1be | 4800 | |
fad41cd7 RH |
4801 | for (si = bsi_start (bb); !bsi_end_p (si); bsi_next (&si)) |
4802 | { | |
4803 | tree stmt = bsi_stmt (si); | |
4804 | int stmt_region; | |
1799e5d5 | 4805 | |
07ed51c9 JJ |
4806 | if (TREE_CODE (stmt) == RESX_EXPR) |
4807 | stmt_region = TREE_INT_CST_LOW (TREE_OPERAND (stmt, 0)); | |
4808 | else | |
4809 | stmt_region = lookup_stmt_eh_region_fn (src_cfun, stmt); | |
7e2df4a1 JJ |
4810 | if (stmt_region > 0) |
4811 | { | |
4812 | if (region < 0) | |
4813 | region = stmt_region; | |
4814 | else if (stmt_region != region) | |
4815 | { | |
4816 | region = eh_region_outermost (src_cfun, stmt_region, region); | |
4817 | gcc_assert (region != -1); | |
4818 | } | |
4819 | } | |
50674e96 | 4820 | } |
fad41cd7 RH |
4821 | |
4822 | return region; | |
50674e96 DN |
4823 | } |
4824 | ||
fad41cd7 RH |
4825 | static tree |
4826 | new_label_mapper (tree decl, void *data) | |
4827 | { | |
4828 | htab_t hash = (htab_t) data; | |
4829 | struct tree_map *m; | |
4830 | void **slot; | |
4831 | ||
4832 | gcc_assert (TREE_CODE (decl) == LABEL_DECL); | |
4833 | ||
4834 | m = xmalloc (sizeof (struct tree_map)); | |
4835 | m->hash = DECL_UID (decl); | |
4836 | m->from = decl; | |
4837 | m->to = create_artificial_label (); | |
4838 | LABEL_DECL_UID (m->to) = LABEL_DECL_UID (decl); | |
4839 | ||
4840 | slot = htab_find_slot_with_hash (hash, m, m->hash, INSERT); | |
4841 | gcc_assert (*slot == NULL); | |
4842 | ||
4843 | *slot = m; | |
4844 | ||
4845 | return m->to; | |
4846 | } | |
50674e96 DN |
4847 | |
4848 | /* Move a single-entry, single-exit region delimited by ENTRY_BB and | |
4849 | EXIT_BB to function DEST_CFUN. The whole region is replaced by a | |
4850 | single basic block in the original CFG and the new basic block is | |
4851 | returned. DEST_CFUN must not have a CFG yet. | |
4852 | ||
4853 | Note that the region need not be a pure SESE region. Blocks inside | |
4854 | the region may contain calls to abort/exit. The only restriction | |
4855 | is that ENTRY_BB should be the only entry point and it must | |
4856 | dominate EXIT_BB. | |
4857 | ||
4858 | All local variables referenced in the region are assumed to be in | |
4859 | the corresponding BLOCK_VARS and unexpanded variable lists | |
4860 | associated with DEST_CFUN. */ | |
4861 | ||
4862 | basic_block | |
4863 | move_sese_region_to_fn (struct function *dest_cfun, basic_block entry_bb, | |
4864 | basic_block exit_bb) | |
4865 | { | |
4866 | VEC(basic_block,heap) *bbs; | |
4867 | basic_block after, bb, *entry_pred, *exit_succ; | |
4868 | struct function *saved_cfun; | |
fad41cd7 | 4869 | int *entry_flag, *exit_flag, eh_offset; |
50674e96 DN |
4870 | unsigned i, num_entry_edges, num_exit_edges; |
4871 | edge e; | |
4872 | edge_iterator ei; | |
4873 | bitmap vars_to_remove; | |
fad41cd7 | 4874 | htab_t new_label_map; |
50674e96 DN |
4875 | |
4876 | saved_cfun = cfun; | |
4877 | ||
4878 | /* Collect all the blocks in the region. Manually add ENTRY_BB | |
4879 | because it won't be added by dfs_enumerate_from. */ | |
4880 | calculate_dominance_info (CDI_DOMINATORS); | |
4881 | ||
4882 | /* If ENTRY does not strictly dominate EXIT, this cannot be an SESE | |
4883 | region. */ | |
4884 | gcc_assert (entry_bb != exit_bb | |
2aee3e57 JJ |
4885 | && (!exit_bb |
4886 | || dominated_by_p (CDI_DOMINATORS, exit_bb, entry_bb))); | |
50674e96 DN |
4887 | |
4888 | bbs = NULL; | |
4889 | VEC_safe_push (basic_block, heap, bbs, entry_bb); | |
4890 | gather_blocks_in_sese_region (entry_bb, exit_bb, &bbs); | |
4891 | ||
4892 | /* Detach ENTRY_BB and EXIT_BB from CFUN->CFG. We need to remember | |
4893 | the predecessor edges to ENTRY_BB and the successor edges to | |
4894 | EXIT_BB so that we can re-attach them to the new basic block that | |
4895 | will replace the region. */ | |
4896 | num_entry_edges = EDGE_COUNT (entry_bb->preds); | |
4897 | entry_pred = (basic_block *) xcalloc (num_entry_edges, sizeof (basic_block)); | |
4898 | entry_flag = (int *) xcalloc (num_entry_edges, sizeof (int)); | |
4899 | i = 0; | |
4900 | for (ei = ei_start (entry_bb->preds); (e = ei_safe_edge (ei)) != NULL;) | |
4901 | { | |
4902 | entry_flag[i] = e->flags; | |
4903 | entry_pred[i++] = e->src; | |
4904 | remove_edge (e); | |
4905 | } | |
4906 | ||
2aee3e57 | 4907 | if (exit_bb) |
50674e96 | 4908 | { |
2aee3e57 JJ |
4909 | num_exit_edges = EDGE_COUNT (exit_bb->succs); |
4910 | exit_succ = (basic_block *) xcalloc (num_exit_edges, | |
4911 | sizeof (basic_block)); | |
4912 | exit_flag = (int *) xcalloc (num_exit_edges, sizeof (int)); | |
4913 | i = 0; | |
4914 | for (ei = ei_start (exit_bb->succs); (e = ei_safe_edge (ei)) != NULL;) | |
4915 | { | |
4916 | exit_flag[i] = e->flags; | |
4917 | exit_succ[i++] = e->dest; | |
4918 | remove_edge (e); | |
4919 | } | |
4920 | } | |
4921 | else | |
4922 | { | |
4923 | num_exit_edges = 0; | |
4924 | exit_succ = NULL; | |
4925 | exit_flag = NULL; | |
50674e96 DN |
4926 | } |
4927 | ||
4928 | /* Switch context to the child function to initialize DEST_FN's CFG. */ | |
4929 | gcc_assert (dest_cfun->cfg == NULL); | |
4930 | cfun = dest_cfun; | |
fad41cd7 | 4931 | |
50674e96 | 4932 | init_empty_tree_cfg (); |
fad41cd7 RH |
4933 | |
4934 | /* Initialize EH information for the new function. */ | |
4935 | eh_offset = 0; | |
4936 | new_label_map = NULL; | |
4937 | if (saved_cfun->eh) | |
4938 | { | |
4939 | int region = -1; | |
4940 | ||
4941 | for (i = 0; VEC_iterate (basic_block, bbs, i, bb); i++) | |
4942 | region = find_outermost_region_in_block (saved_cfun, bb, region); | |
4943 | ||
4944 | init_eh_for_function (); | |
4945 | if (region != -1) | |
4946 | { | |
4947 | new_label_map = htab_create (17, tree_map_hash, tree_map_eq, free); | |
4948 | eh_offset = duplicate_eh_regions (saved_cfun, new_label_mapper, | |
4949 | new_label_map, region, 0); | |
4950 | } | |
4951 | } | |
4952 | ||
50674e96 DN |
4953 | cfun = saved_cfun; |
4954 | ||
4955 | /* Move blocks from BBS into DEST_CFUN. */ | |
4956 | gcc_assert (VEC_length (basic_block, bbs) >= 2); | |
4957 | after = dest_cfun->cfg->x_entry_block_ptr; | |
4958 | vars_to_remove = BITMAP_ALLOC (NULL); | |
4959 | for (i = 0; VEC_iterate (basic_block, bbs, i, bb); i++) | |
4960 | { | |
4961 | /* No need to update edge counts on the last block. It has | |
4962 | already been updated earlier when we detached the region from | |
4963 | the original CFG. */ | |
fad41cd7 RH |
4964 | move_block_to_fn (dest_cfun, bb, after, bb != exit_bb, vars_to_remove, |
4965 | new_label_map, eh_offset); | |
50674e96 DN |
4966 | after = bb; |
4967 | } | |
4968 | ||
fad41cd7 RH |
4969 | if (new_label_map) |
4970 | htab_delete (new_label_map); | |
4971 | ||
50674e96 DN |
4972 | /* Remove the variables marked in VARS_TO_REMOVE from |
4973 | CFUN->UNEXPANDED_VAR_LIST. Otherwise, they will be given a | |
4974 | DECL_RTL in the context of CFUN. */ | |
4975 | if (!bitmap_empty_p (vars_to_remove)) | |
4976 | { | |
4977 | tree *p; | |
4978 | ||
4979 | for (p = &cfun->unexpanded_var_list; *p; ) | |
4980 | { | |
4981 | tree var = TREE_VALUE (*p); | |
4982 | if (bitmap_bit_p (vars_to_remove, DECL_UID (var))) | |
4983 | { | |
4984 | *p = TREE_CHAIN (*p); | |
4985 | continue; | |
4986 | } | |
4987 | ||
4988 | p = &TREE_CHAIN (*p); | |
4989 | } | |
4990 | } | |
4991 | ||
4992 | BITMAP_FREE (vars_to_remove); | |
4993 | ||
4994 | /* Rewire the entry and exit blocks. The successor to the entry | |
4995 | block turns into the successor of DEST_FN's ENTRY_BLOCK_PTR in | |
4996 | the child function. Similarly, the predecessor of DEST_FN's | |
4997 | EXIT_BLOCK_PTR turns into the predecessor of EXIT_BLOCK_PTR. We | |
4998 | need to switch CFUN between DEST_CFUN and SAVED_CFUN so that the | |
4999 | various CFG manipulation function get to the right CFG. | |
5000 | ||
5001 | FIXME, this is silly. The CFG ought to become a parameter to | |
5002 | these helpers. */ | |
5003 | cfun = dest_cfun; | |
5004 | make_edge (ENTRY_BLOCK_PTR, entry_bb, EDGE_FALLTHRU); | |
2aee3e57 JJ |
5005 | if (exit_bb) |
5006 | make_edge (exit_bb, EXIT_BLOCK_PTR, 0); | |
50674e96 DN |
5007 | cfun = saved_cfun; |
5008 | ||
5009 | /* Back in the original function, the SESE region has disappeared, | |
5010 | create a new basic block in its place. */ | |
5011 | bb = create_empty_bb (entry_pred[0]); | |
5012 | for (i = 0; i < num_entry_edges; i++) | |
5013 | make_edge (entry_pred[i], bb, entry_flag[i]); | |
5014 | ||
5015 | for (i = 0; i < num_exit_edges; i++) | |
5016 | make_edge (bb, exit_succ[i], exit_flag[i]); | |
5017 | ||
2aee3e57 JJ |
5018 | if (exit_bb) |
5019 | { | |
5020 | free (exit_flag); | |
5021 | free (exit_succ); | |
5022 | } | |
50674e96 DN |
5023 | free (entry_flag); |
5024 | free (entry_pred); | |
50674e96 DN |
5025 | free_dominance_info (CDI_DOMINATORS); |
5026 | free_dominance_info (CDI_POST_DOMINATORS); | |
5027 | VEC_free (basic_block, heap, bbs); | |
5028 | ||
5029 | return bb; | |
5030 | } | |
5031 | ||
84d65814 | 5032 | |
6de9cd9a DN |
5033 | /* Dump FUNCTION_DECL FN to file FILE using FLAGS (see TDF_* in tree.h) */ |
5034 | ||
5035 | void | |
5036 | dump_function_to_file (tree fn, FILE *file, int flags) | |
5037 | { | |
5038 | tree arg, vars, var; | |
5039 | bool ignore_topmost_bind = false, any_var = false; | |
5040 | basic_block bb; | |
5041 | tree chain; | |
953ff289 | 5042 | struct function *saved_cfun; |
6531d1be | 5043 | |
673fda6b | 5044 | fprintf (file, "%s (", lang_hooks.decl_printable_name (fn, 2)); |
6de9cd9a DN |
5045 | |
5046 | arg = DECL_ARGUMENTS (fn); | |
5047 | while (arg) | |
5048 | { | |
5049 | print_generic_expr (file, arg, dump_flags); | |
5050 | if (TREE_CHAIN (arg)) | |
5051 | fprintf (file, ", "); | |
5052 | arg = TREE_CHAIN (arg); | |
5053 | } | |
5054 | fprintf (file, ")\n"); | |
5055 | ||
cc7220fd JH |
5056 | if (flags & TDF_DETAILS) |
5057 | dump_eh_tree (file, DECL_STRUCT_FUNCTION (fn)); | |
6de9cd9a DN |
5058 | if (flags & TDF_RAW) |
5059 | { | |
5060 | dump_node (fn, TDF_SLIM | flags, file); | |
5061 | return; | |
5062 | } | |
5063 | ||
953ff289 DN |
5064 | /* Switch CFUN to point to FN. */ |
5065 | saved_cfun = cfun; | |
5066 | cfun = DECL_STRUCT_FUNCTION (fn); | |
5067 | ||
6de9cd9a DN |
5068 | /* When GIMPLE is lowered, the variables are no longer available in |
5069 | BIND_EXPRs, so display them separately. */ | |
32a87d45 | 5070 | if (cfun && cfun->decl == fn && cfun->unexpanded_var_list) |
6de9cd9a DN |
5071 | { |
5072 | ignore_topmost_bind = true; | |
5073 | ||
5074 | fprintf (file, "{\n"); | |
5075 | for (vars = cfun->unexpanded_var_list; vars; vars = TREE_CHAIN (vars)) | |
5076 | { | |
5077 | var = TREE_VALUE (vars); | |
5078 | ||
5079 | print_generic_decl (file, var, flags); | |
5080 | fprintf (file, "\n"); | |
5081 | ||
5082 | any_var = true; | |
5083 | } | |
5084 | } | |
5085 | ||
32a87d45 | 5086 | if (cfun && cfun->decl == fn && cfun->cfg && basic_block_info) |
6de9cd9a DN |
5087 | { |
5088 | /* Make a CFG based dump. */ | |
878f99d2 | 5089 | check_bb_profile (ENTRY_BLOCK_PTR, file); |
6de9cd9a DN |
5090 | if (!ignore_topmost_bind) |
5091 | fprintf (file, "{\n"); | |
5092 | ||
5093 | if (any_var && n_basic_blocks) | |
5094 | fprintf (file, "\n"); | |
5095 | ||
5096 | FOR_EACH_BB (bb) | |
5097 | dump_generic_bb (file, bb, 2, flags); | |
6531d1be | 5098 | |
6de9cd9a | 5099 | fprintf (file, "}\n"); |
878f99d2 | 5100 | check_bb_profile (EXIT_BLOCK_PTR, file); |
6de9cd9a DN |
5101 | } |
5102 | else | |
5103 | { | |
5104 | int indent; | |
5105 | ||
5106 | /* Make a tree based dump. */ | |
5107 | chain = DECL_SAVED_TREE (fn); | |
5108 | ||
953ff289 | 5109 | if (chain && TREE_CODE (chain) == BIND_EXPR) |
6de9cd9a DN |
5110 | { |
5111 | if (ignore_topmost_bind) | |
5112 | { | |
5113 | chain = BIND_EXPR_BODY (chain); | |
5114 | indent = 2; | |
5115 | } | |
5116 | else | |
5117 | indent = 0; | |
5118 | } | |
5119 | else | |
5120 | { | |
5121 | if (!ignore_topmost_bind) | |
5122 | fprintf (file, "{\n"); | |
5123 | indent = 2; | |
5124 | } | |
5125 | ||
5126 | if (any_var) | |
5127 | fprintf (file, "\n"); | |
5128 | ||
5129 | print_generic_stmt_indented (file, chain, flags, indent); | |
5130 | if (ignore_topmost_bind) | |
5131 | fprintf (file, "}\n"); | |
5132 | } | |
5133 | ||
5134 | fprintf (file, "\n\n"); | |
953ff289 DN |
5135 | |
5136 | /* Restore CFUN. */ | |
5137 | cfun = saved_cfun; | |
5138 | } | |
5139 | ||
5140 | ||
5141 | /* Dump FUNCTION_DECL FN to stderr using FLAGS (see TDF_* in tree.h) */ | |
5142 | ||
5143 | void | |
5144 | debug_function (tree fn, int flags) | |
5145 | { | |
5146 | dump_function_to_file (fn, stderr, flags); | |
6de9cd9a DN |
5147 | } |
5148 | ||
5149 | ||
5150 | /* Pretty print of the loops intermediate representation. */ | |
5151 | static void print_loop (FILE *, struct loop *, int); | |
628f6a4e BE |
5152 | static void print_pred_bbs (FILE *, basic_block bb); |
5153 | static void print_succ_bbs (FILE *, basic_block bb); | |
6de9cd9a DN |
5154 | |
5155 | ||
d7770457 | 5156 | /* Print on FILE the indexes for the predecessors of basic_block BB. */ |
6de9cd9a DN |
5157 | |
5158 | static void | |
628f6a4e | 5159 | print_pred_bbs (FILE *file, basic_block bb) |
6de9cd9a | 5160 | { |
628f6a4e BE |
5161 | edge e; |
5162 | edge_iterator ei; | |
5163 | ||
5164 | FOR_EACH_EDGE (e, ei, bb->preds) | |
d7770457 | 5165 | fprintf (file, "bb_%d ", e->src->index); |
6de9cd9a DN |
5166 | } |
5167 | ||
5168 | ||
d7770457 | 5169 | /* Print on FILE the indexes for the successors of basic_block BB. */ |
6de9cd9a DN |
5170 | |
5171 | static void | |
628f6a4e | 5172 | print_succ_bbs (FILE *file, basic_block bb) |
6de9cd9a | 5173 | { |
628f6a4e BE |
5174 | edge e; |
5175 | edge_iterator ei; | |
5176 | ||
5177 | FOR_EACH_EDGE (e, ei, bb->succs) | |
d7770457 | 5178 | fprintf (file, "bb_%d ", e->dest->index); |
6de9cd9a DN |
5179 | } |
5180 | ||
5181 | ||
5182 | /* Pretty print LOOP on FILE, indented INDENT spaces. */ | |
5183 | ||
5184 | static void | |
5185 | print_loop (FILE *file, struct loop *loop, int indent) | |
5186 | { | |
5187 | char *s_indent; | |
5188 | basic_block bb; | |
6531d1be | 5189 | |
6de9cd9a DN |
5190 | if (loop == NULL) |
5191 | return; | |
5192 | ||
5193 | s_indent = (char *) alloca ((size_t) indent + 1); | |
5194 | memset ((void *) s_indent, ' ', (size_t) indent); | |
5195 | s_indent[indent] = '\0'; | |
5196 | ||
5197 | /* Print the loop's header. */ | |
5198 | fprintf (file, "%sloop_%d\n", s_indent, loop->num); | |
6531d1be | 5199 | |
6de9cd9a DN |
5200 | /* Print the loop's body. */ |
5201 | fprintf (file, "%s{\n", s_indent); | |
5202 | FOR_EACH_BB (bb) | |
5203 | if (bb->loop_father == loop) | |
5204 | { | |
5205 | /* Print the basic_block's header. */ | |
5206 | fprintf (file, "%s bb_%d (preds = {", s_indent, bb->index); | |
628f6a4e | 5207 | print_pred_bbs (file, bb); |
6de9cd9a | 5208 | fprintf (file, "}, succs = {"); |
628f6a4e | 5209 | print_succ_bbs (file, bb); |
6de9cd9a | 5210 | fprintf (file, "})\n"); |
6531d1be | 5211 | |
6de9cd9a DN |
5212 | /* Print the basic_block's body. */ |
5213 | fprintf (file, "%s {\n", s_indent); | |
5214 | tree_dump_bb (bb, file, indent + 4); | |
5215 | fprintf (file, "%s }\n", s_indent); | |
5216 | } | |
6531d1be | 5217 | |
6de9cd9a DN |
5218 | print_loop (file, loop->inner, indent + 2); |
5219 | fprintf (file, "%s}\n", s_indent); | |
5220 | print_loop (file, loop->next, indent); | |
5221 | } | |
5222 | ||
5223 | ||
5224 | /* Follow a CFG edge from the entry point of the program, and on entry | |
5225 | of a loop, pretty print the loop structure on FILE. */ | |
5226 | ||
6531d1be | 5227 | void |
6de9cd9a DN |
5228 | print_loop_ir (FILE *file) |
5229 | { | |
5230 | basic_block bb; | |
6531d1be | 5231 | |
24bd1a0b | 5232 | bb = BASIC_BLOCK (NUM_FIXED_BLOCKS); |
6de9cd9a DN |
5233 | if (bb && bb->loop_father) |
5234 | print_loop (file, bb->loop_father, 0); | |
5235 | } | |
5236 | ||
5237 | ||
5238 | /* Debugging loops structure at tree level. */ | |
5239 | ||
6531d1be | 5240 | void |
6de9cd9a DN |
5241 | debug_loop_ir (void) |
5242 | { | |
5243 | print_loop_ir (stderr); | |
5244 | } | |
5245 | ||
5246 | ||
5247 | /* Return true if BB ends with a call, possibly followed by some | |
5248 | instructions that must stay with the call. Return false, | |
5249 | otherwise. */ | |
5250 | ||
5251 | static bool | |
5252 | tree_block_ends_with_call_p (basic_block bb) | |
5253 | { | |
5254 | block_stmt_iterator bsi = bsi_last (bb); | |
cd709752 | 5255 | return get_call_expr_in (bsi_stmt (bsi)) != NULL; |
6de9cd9a DN |
5256 | } |
5257 | ||
5258 | ||
5259 | /* Return true if BB ends with a conditional branch. Return false, | |
5260 | otherwise. */ | |
5261 | ||
5262 | static bool | |
5263 | tree_block_ends_with_condjump_p (basic_block bb) | |
5264 | { | |
9885da8e ZD |
5265 | tree stmt = last_stmt (bb); |
5266 | return (stmt && TREE_CODE (stmt) == COND_EXPR); | |
6de9cd9a DN |
5267 | } |
5268 | ||
5269 | ||
5270 | /* Return true if we need to add fake edge to exit at statement T. | |
5271 | Helper function for tree_flow_call_edges_add. */ | |
5272 | ||
5273 | static bool | |
5274 | need_fake_edge_p (tree t) | |
5275 | { | |
cd709752 | 5276 | tree call; |
6de9cd9a DN |
5277 | |
5278 | /* NORETURN and LONGJMP calls already have an edge to exit. | |
321cf1f2 | 5279 | CONST and PURE calls do not need one. |
6de9cd9a DN |
5280 | We don't currently check for CONST and PURE here, although |
5281 | it would be a good idea, because those attributes are | |
5282 | figured out from the RTL in mark_constant_function, and | |
5283 | the counter incrementation code from -fprofile-arcs | |
5284 | leads to different results from -fbranch-probabilities. */ | |
cd709752 RH |
5285 | call = get_call_expr_in (t); |
5286 | if (call | |
321cf1f2 | 5287 | && !(call_expr_flags (call) & ECF_NORETURN)) |
6de9cd9a DN |
5288 | return true; |
5289 | ||
5290 | if (TREE_CODE (t) == ASM_EXPR | |
5291 | && (ASM_VOLATILE_P (t) || ASM_INPUT_P (t))) | |
5292 | return true; | |
5293 | ||
5294 | return false; | |
5295 | } | |
5296 | ||
5297 | ||
5298 | /* Add fake edges to the function exit for any non constant and non | |
5299 | noreturn calls, volatile inline assembly in the bitmap of blocks | |
5300 | specified by BLOCKS or to the whole CFG if BLOCKS is zero. Return | |
5301 | the number of blocks that were split. | |
5302 | ||
5303 | The goal is to expose cases in which entering a basic block does | |
5304 | not imply that all subsequent instructions must be executed. */ | |
5305 | ||
5306 | static int | |
5307 | tree_flow_call_edges_add (sbitmap blocks) | |
5308 | { | |
5309 | int i; | |
5310 | int blocks_split = 0; | |
5311 | int last_bb = last_basic_block; | |
5312 | bool check_last_block = false; | |
5313 | ||
24bd1a0b | 5314 | if (n_basic_blocks == NUM_FIXED_BLOCKS) |
6de9cd9a DN |
5315 | return 0; |
5316 | ||
5317 | if (! blocks) | |
5318 | check_last_block = true; | |
5319 | else | |
5320 | check_last_block = TEST_BIT (blocks, EXIT_BLOCK_PTR->prev_bb->index); | |
5321 | ||
5322 | /* In the last basic block, before epilogue generation, there will be | |
5323 | a fallthru edge to EXIT. Special care is required if the last insn | |
5324 | of the last basic block is a call because make_edge folds duplicate | |
5325 | edges, which would result in the fallthru edge also being marked | |
5326 | fake, which would result in the fallthru edge being removed by | |
5327 | remove_fake_edges, which would result in an invalid CFG. | |
5328 | ||
5329 | Moreover, we can't elide the outgoing fake edge, since the block | |
5330 | profiler needs to take this into account in order to solve the minimal | |
5331 | spanning tree in the case that the call doesn't return. | |
5332 | ||
5333 | Handle this by adding a dummy instruction in a new last basic block. */ | |
5334 | if (check_last_block) | |
5335 | { | |
5336 | basic_block bb = EXIT_BLOCK_PTR->prev_bb; | |
5337 | block_stmt_iterator bsi = bsi_last (bb); | |
5338 | tree t = NULL_TREE; | |
5339 | if (!bsi_end_p (bsi)) | |
5340 | t = bsi_stmt (bsi); | |
5341 | ||
6a60530d | 5342 | if (t && need_fake_edge_p (t)) |
6de9cd9a DN |
5343 | { |
5344 | edge e; | |
5345 | ||
9ff3d2de JL |
5346 | e = find_edge (bb, EXIT_BLOCK_PTR); |
5347 | if (e) | |
5348 | { | |
5349 | bsi_insert_on_edge (e, build_empty_stmt ()); | |
5350 | bsi_commit_edge_inserts (); | |
5351 | } | |
6de9cd9a DN |
5352 | } |
5353 | } | |
5354 | ||
5355 | /* Now add fake edges to the function exit for any non constant | |
5356 | calls since there is no way that we can determine if they will | |
5357 | return or not... */ | |
5358 | for (i = 0; i < last_bb; i++) | |
5359 | { | |
5360 | basic_block bb = BASIC_BLOCK (i); | |
5361 | block_stmt_iterator bsi; | |
5362 | tree stmt, last_stmt; | |
5363 | ||
5364 | if (!bb) | |
5365 | continue; | |
5366 | ||
5367 | if (blocks && !TEST_BIT (blocks, i)) | |
5368 | continue; | |
5369 | ||
5370 | bsi = bsi_last (bb); | |
5371 | if (!bsi_end_p (bsi)) | |
5372 | { | |
5373 | last_stmt = bsi_stmt (bsi); | |
5374 | do | |
5375 | { | |
5376 | stmt = bsi_stmt (bsi); | |
5377 | if (need_fake_edge_p (stmt)) | |
5378 | { | |
5379 | edge e; | |
5380 | /* The handling above of the final block before the | |
5381 | epilogue should be enough to verify that there is | |
5382 | no edge to the exit block in CFG already. | |
5383 | Calling make_edge in such case would cause us to | |
5384 | mark that edge as fake and remove it later. */ | |
5385 | #ifdef ENABLE_CHECKING | |
5386 | if (stmt == last_stmt) | |
628f6a4e | 5387 | { |
9ff3d2de JL |
5388 | e = find_edge (bb, EXIT_BLOCK_PTR); |
5389 | gcc_assert (e == NULL); | |
628f6a4e | 5390 | } |
6de9cd9a DN |
5391 | #endif |
5392 | ||
5393 | /* Note that the following may create a new basic block | |
5394 | and renumber the existing basic blocks. */ | |
5395 | if (stmt != last_stmt) | |
5396 | { | |
5397 | e = split_block (bb, stmt); | |
5398 | if (e) | |
5399 | blocks_split++; | |
5400 | } | |
5401 | make_edge (bb, EXIT_BLOCK_PTR, EDGE_FAKE); | |
5402 | } | |
5403 | bsi_prev (&bsi); | |
5404 | } | |
5405 | while (!bsi_end_p (bsi)); | |
5406 | } | |
5407 | } | |
5408 | ||
5409 | if (blocks_split) | |
5410 | verify_flow_info (); | |
5411 | ||
5412 | return blocks_split; | |
5413 | } | |
5414 | ||
4f6c2131 EB |
5415 | /* Purge dead abnormal call edges from basic block BB. */ |
5416 | ||
5417 | bool | |
5418 | tree_purge_dead_abnormal_call_edges (basic_block bb) | |
5419 | { | |
5420 | bool changed = tree_purge_dead_eh_edges (bb); | |
5421 | ||
5422 | if (current_function_has_nonlocal_label) | |
5423 | { | |
5424 | tree stmt = last_stmt (bb); | |
5425 | edge_iterator ei; | |
5426 | edge e; | |
5427 | ||
5428 | if (!(stmt && tree_can_make_abnormal_goto (stmt))) | |
5429 | for (ei = ei_start (bb->succs); (e = ei_safe_edge (ei)); ) | |
5430 | { | |
5431 | if (e->flags & EDGE_ABNORMAL) | |
5432 | { | |
5433 | remove_edge (e); | |
5434 | changed = true; | |
5435 | } | |
5436 | else | |
5437 | ei_next (&ei); | |
5438 | } | |
5439 | ||
5440 | /* See tree_purge_dead_eh_edges below. */ | |
5441 | if (changed) | |
5442 | free_dominance_info (CDI_DOMINATORS); | |
5443 | } | |
5444 | ||
5445 | return changed; | |
5446 | } | |
5447 | ||
5448 | /* Purge dead EH edges from basic block BB. */ | |
5449 | ||
1eaba2f2 RH |
5450 | bool |
5451 | tree_purge_dead_eh_edges (basic_block bb) | |
5452 | { | |
5453 | bool changed = false; | |
628f6a4e BE |
5454 | edge e; |
5455 | edge_iterator ei; | |
1eaba2f2 RH |
5456 | tree stmt = last_stmt (bb); |
5457 | ||
5458 | if (stmt && tree_can_throw_internal (stmt)) | |
5459 | return false; | |
5460 | ||
628f6a4e | 5461 | for (ei = ei_start (bb->succs); (e = ei_safe_edge (ei)); ) |
1eaba2f2 | 5462 | { |
1eaba2f2 RH |
5463 | if (e->flags & EDGE_EH) |
5464 | { | |
d0d2cc21 | 5465 | remove_edge (e); |
1eaba2f2 RH |
5466 | changed = true; |
5467 | } | |
628f6a4e BE |
5468 | else |
5469 | ei_next (&ei); | |
1eaba2f2 RH |
5470 | } |
5471 | ||
69d49802 JJ |
5472 | /* Removal of dead EH edges might change dominators of not |
5473 | just immediate successors. E.g. when bb1 is changed so that | |
5474 | it no longer can throw and bb1->bb3 and bb1->bb4 are dead | |
5475 | eh edges purged by this function in: | |
5476 | 0 | |
5477 | / \ | |
5478 | v v | |
5479 | 1-->2 | |
5480 | / \ | | |
5481 | v v | | |
5482 | 3-->4 | | |
5483 | \ v | |
5484 | --->5 | |
5485 | | | |
5486 | - | |
5487 | idom(bb5) must be recomputed. For now just free the dominance | |
5488 | info. */ | |
5489 | if (changed) | |
5490 | free_dominance_info (CDI_DOMINATORS); | |
5491 | ||
1eaba2f2 RH |
5492 | return changed; |
5493 | } | |
5494 | ||
5495 | bool | |
5496 | tree_purge_all_dead_eh_edges (bitmap blocks) | |
5497 | { | |
5498 | bool changed = false; | |
3cd8c58a | 5499 | unsigned i; |
87c476a2 | 5500 | bitmap_iterator bi; |
1eaba2f2 | 5501 | |
87c476a2 ZD |
5502 | EXECUTE_IF_SET_IN_BITMAP (blocks, 0, i, bi) |
5503 | { | |
5504 | changed |= tree_purge_dead_eh_edges (BASIC_BLOCK (i)); | |
5505 | } | |
1eaba2f2 RH |
5506 | |
5507 | return changed; | |
5508 | } | |
6de9cd9a | 5509 | |
a100ac1e KH |
5510 | /* This function is called whenever a new edge is created or |
5511 | redirected. */ | |
5512 | ||
5513 | static void | |
5514 | tree_execute_on_growing_pred (edge e) | |
5515 | { | |
5516 | basic_block bb = e->dest; | |
5517 | ||
5518 | if (phi_nodes (bb)) | |
5519 | reserve_phi_args_for_new_edge (bb); | |
5520 | } | |
5521 | ||
e51546f8 KH |
5522 | /* This function is called immediately before edge E is removed from |
5523 | the edge vector E->dest->preds. */ | |
5524 | ||
5525 | static void | |
5526 | tree_execute_on_shrinking_pred (edge e) | |
5527 | { | |
5528 | if (phi_nodes (e->dest)) | |
5529 | remove_phi_args (e); | |
5530 | } | |
5531 | ||
1cb7dfc3 MH |
5532 | /*--------------------------------------------------------------------------- |
5533 | Helper functions for Loop versioning | |
5534 | ---------------------------------------------------------------------------*/ | |
5535 | ||
5536 | /* Adjust phi nodes for 'first' basic block. 'second' basic block is a copy | |
5537 | of 'first'. Both of them are dominated by 'new_head' basic block. When | |
5538 | 'new_head' was created by 'second's incoming edge it received phi arguments | |
5539 | on the edge by split_edge(). Later, additional edge 'e' was created to | |
6531d1be BF |
5540 | connect 'new_head' and 'first'. Now this routine adds phi args on this |
5541 | additional edge 'e' that new_head to second edge received as part of edge | |
1cb7dfc3 MH |
5542 | splitting. |
5543 | */ | |
5544 | ||
5545 | static void | |
5546 | tree_lv_adjust_loop_header_phi (basic_block first, basic_block second, | |
5547 | basic_block new_head, edge e) | |
5548 | { | |
5549 | tree phi1, phi2; | |
d0e12fc6 KH |
5550 | edge e2 = find_edge (new_head, second); |
5551 | ||
5552 | /* Because NEW_HEAD has been created by splitting SECOND's incoming | |
5553 | edge, we should always have an edge from NEW_HEAD to SECOND. */ | |
5554 | gcc_assert (e2 != NULL); | |
1cb7dfc3 MH |
5555 | |
5556 | /* Browse all 'second' basic block phi nodes and add phi args to | |
5557 | edge 'e' for 'first' head. PHI args are always in correct order. */ | |
5558 | ||
6531d1be BF |
5559 | for (phi2 = phi_nodes (second), phi1 = phi_nodes (first); |
5560 | phi2 && phi1; | |
1cb7dfc3 MH |
5561 | phi2 = PHI_CHAIN (phi2), phi1 = PHI_CHAIN (phi1)) |
5562 | { | |
d0e12fc6 KH |
5563 | tree def = PHI_ARG_DEF (phi2, e2->dest_idx); |
5564 | add_phi_arg (phi1, def, e); | |
1cb7dfc3 MH |
5565 | } |
5566 | } | |
5567 | ||
6531d1be BF |
5568 | /* Adds a if else statement to COND_BB with condition COND_EXPR. |
5569 | SECOND_HEAD is the destination of the THEN and FIRST_HEAD is | |
1cb7dfc3 MH |
5570 | the destination of the ELSE part. */ |
5571 | static void | |
5572 | tree_lv_add_condition_to_bb (basic_block first_head, basic_block second_head, | |
5573 | basic_block cond_bb, void *cond_e) | |
5574 | { | |
5575 | block_stmt_iterator bsi; | |
5576 | tree goto1 = NULL_TREE; | |
5577 | tree goto2 = NULL_TREE; | |
5578 | tree new_cond_expr = NULL_TREE; | |
5579 | tree cond_expr = (tree) cond_e; | |
5580 | edge e0; | |
5581 | ||
5582 | /* Build new conditional expr */ | |
5583 | goto1 = build1 (GOTO_EXPR, void_type_node, tree_block_label (first_head)); | |
5584 | goto2 = build1 (GOTO_EXPR, void_type_node, tree_block_label (second_head)); | |
5585 | new_cond_expr = build3 (COND_EXPR, void_type_node, cond_expr, goto1, goto2); | |
5586 | ||
6531d1be BF |
5587 | /* Add new cond in cond_bb. */ |
5588 | bsi = bsi_start (cond_bb); | |
1cb7dfc3 MH |
5589 | bsi_insert_after (&bsi, new_cond_expr, BSI_NEW_STMT); |
5590 | /* Adjust edges appropriately to connect new head with first head | |
5591 | as well as second head. */ | |
5592 | e0 = single_succ_edge (cond_bb); | |
5593 | e0->flags &= ~EDGE_FALLTHRU; | |
5594 | e0->flags |= EDGE_FALSE_VALUE; | |
5595 | } | |
5596 | ||
6de9cd9a DN |
5597 | struct cfg_hooks tree_cfg_hooks = { |
5598 | "tree", | |
5599 | tree_verify_flow_info, | |
5600 | tree_dump_bb, /* dump_bb */ | |
5601 | create_bb, /* create_basic_block */ | |
5602 | tree_redirect_edge_and_branch,/* redirect_edge_and_branch */ | |
5603 | tree_redirect_edge_and_branch_force,/* redirect_edge_and_branch_force */ | |
5604 | remove_bb, /* delete_basic_block */ | |
5605 | tree_split_block, /* split_block */ | |
5606 | tree_move_block_after, /* move_block_after */ | |
5607 | tree_can_merge_blocks_p, /* can_merge_blocks_p */ | |
5608 | tree_merge_blocks, /* merge_blocks */ | |
5609 | tree_predict_edge, /* predict_edge */ | |
5610 | tree_predicted_by_p, /* predicted_by_p */ | |
5611 | tree_can_duplicate_bb_p, /* can_duplicate_block_p */ | |
5612 | tree_duplicate_bb, /* duplicate_block */ | |
5613 | tree_split_edge, /* split_edge */ | |
5614 | tree_make_forwarder_block, /* make_forward_block */ | |
5615 | NULL, /* tidy_fallthru_edge */ | |
5616 | tree_block_ends_with_call_p, /* block_ends_with_call_p */ | |
5617 | tree_block_ends_with_condjump_p, /* block_ends_with_condjump_p */ | |
d9d4706f | 5618 | tree_flow_call_edges_add, /* flow_call_edges_add */ |
a100ac1e | 5619 | tree_execute_on_growing_pred, /* execute_on_growing_pred */ |
e51546f8 | 5620 | tree_execute_on_shrinking_pred, /* execute_on_shrinking_pred */ |
1cb7dfc3 MH |
5621 | tree_duplicate_loop_to_header_edge, /* duplicate loop for trees */ |
5622 | tree_lv_add_condition_to_bb, /* lv_add_condition_to_bb */ | |
5623 | tree_lv_adjust_loop_header_phi, /* lv_adjust_loop_header_phi*/ | |
5624 | extract_true_false_edges_from_block, /* extract_cond_bb_edges */ | |
6531d1be | 5625 | flush_pending_stmts /* flush_pending_stmts */ |
6de9cd9a DN |
5626 | }; |
5627 | ||
5628 | ||
5629 | /* Split all critical edges. */ | |
5630 | ||
c2924966 | 5631 | static unsigned int |
6de9cd9a DN |
5632 | split_critical_edges (void) |
5633 | { | |
5634 | basic_block bb; | |
5635 | edge e; | |
628f6a4e | 5636 | edge_iterator ei; |
6de9cd9a | 5637 | |
d6be0d7f JL |
5638 | /* split_edge can redirect edges out of SWITCH_EXPRs, which can get |
5639 | expensive. So we want to enable recording of edge to CASE_LABEL_EXPR | |
5640 | mappings around the calls to split_edge. */ | |
5641 | start_recording_case_labels (); | |
6de9cd9a DN |
5642 | FOR_ALL_BB (bb) |
5643 | { | |
628f6a4e | 5644 | FOR_EACH_EDGE (e, ei, bb->succs) |
6de9cd9a DN |
5645 | if (EDGE_CRITICAL_P (e) && !(e->flags & EDGE_ABNORMAL)) |
5646 | { | |
5647 | split_edge (e); | |
5648 | } | |
5649 | } | |
d6be0d7f | 5650 | end_recording_case_labels (); |
c2924966 | 5651 | return 0; |
6de9cd9a DN |
5652 | } |
5653 | ||
6531d1be | 5654 | struct tree_opt_pass pass_split_crit_edges = |
6de9cd9a | 5655 | { |
5d44aeed | 5656 | "crited", /* name */ |
6de9cd9a DN |
5657 | NULL, /* gate */ |
5658 | split_critical_edges, /* execute */ | |
5659 | NULL, /* sub */ | |
5660 | NULL, /* next */ | |
5661 | 0, /* static_pass_number */ | |
5662 | TV_TREE_SPLIT_EDGES, /* tv_id */ | |
5663 | PROP_cfg, /* properties required */ | |
5664 | PROP_no_crit_edges, /* properties_provided */ | |
5665 | 0, /* properties_destroyed */ | |
5666 | 0, /* todo_flags_start */ | |
9f8628ba PB |
5667 | TODO_dump_func, /* todo_flags_finish */ |
5668 | 0 /* letter */ | |
6de9cd9a | 5669 | }; |
26277d41 PB |
5670 | |
5671 | \f | |
5672 | /* Return EXP if it is a valid GIMPLE rvalue, else gimplify it into | |
5673 | a temporary, make sure and register it to be renamed if necessary, | |
5674 | and finally return the temporary. Put the statements to compute | |
5675 | EXP before the current statement in BSI. */ | |
5676 | ||
5677 | tree | |
5678 | gimplify_val (block_stmt_iterator *bsi, tree type, tree exp) | |
5679 | { | |
5680 | tree t, new_stmt, orig_stmt; | |
5681 | ||
5682 | if (is_gimple_val (exp)) | |
5683 | return exp; | |
5684 | ||
5685 | t = make_rename_temp (type, NULL); | |
07beea0d | 5686 | new_stmt = build2_gimple (GIMPLE_MODIFY_STMT, t, exp); |
26277d41 PB |
5687 | |
5688 | orig_stmt = bsi_stmt (*bsi); | |
5689 | SET_EXPR_LOCUS (new_stmt, EXPR_LOCUS (orig_stmt)); | |
5690 | TREE_BLOCK (new_stmt) = TREE_BLOCK (orig_stmt); | |
5691 | ||
5692 | bsi_insert_before (bsi, new_stmt, BSI_SAME_STMT); | |
5cd4ec7f | 5693 | if (gimple_in_ssa_p (cfun)) |
cfaab3a9 | 5694 | mark_symbols_for_renaming (new_stmt); |
26277d41 PB |
5695 | |
5696 | return t; | |
5697 | } | |
5698 | ||
5699 | /* Build a ternary operation and gimplify it. Emit code before BSI. | |
5700 | Return the gimple_val holding the result. */ | |
5701 | ||
5702 | tree | |
5703 | gimplify_build3 (block_stmt_iterator *bsi, enum tree_code code, | |
5704 | tree type, tree a, tree b, tree c) | |
5705 | { | |
5706 | tree ret; | |
5707 | ||
987b67bc | 5708 | ret = fold_build3 (code, type, a, b, c); |
26277d41 PB |
5709 | STRIP_NOPS (ret); |
5710 | ||
5711 | return gimplify_val (bsi, type, ret); | |
5712 | } | |
5713 | ||
5714 | /* Build a binary operation and gimplify it. Emit code before BSI. | |
5715 | Return the gimple_val holding the result. */ | |
5716 | ||
5717 | tree | |
5718 | gimplify_build2 (block_stmt_iterator *bsi, enum tree_code code, | |
5719 | tree type, tree a, tree b) | |
5720 | { | |
5721 | tree ret; | |
5722 | ||
987b67bc | 5723 | ret = fold_build2 (code, type, a, b); |
26277d41 PB |
5724 | STRIP_NOPS (ret); |
5725 | ||
5726 | return gimplify_val (bsi, type, ret); | |
5727 | } | |
5728 | ||
5729 | /* Build a unary operation and gimplify it. Emit code before BSI. | |
5730 | Return the gimple_val holding the result. */ | |
5731 | ||
5732 | tree | |
5733 | gimplify_build1 (block_stmt_iterator *bsi, enum tree_code code, tree type, | |
5734 | tree a) | |
5735 | { | |
5736 | tree ret; | |
5737 | ||
987b67bc | 5738 | ret = fold_build1 (code, type, a); |
26277d41 PB |
5739 | STRIP_NOPS (ret); |
5740 | ||
5741 | return gimplify_val (bsi, type, ret); | |
5742 | } | |
5743 | ||
5744 | ||
6de9cd9a DN |
5745 | \f |
5746 | /* Emit return warnings. */ | |
5747 | ||
c2924966 | 5748 | static unsigned int |
6de9cd9a DN |
5749 | execute_warn_function_return (void) |
5750 | { | |
9506ac2b PB |
5751 | #ifdef USE_MAPPED_LOCATION |
5752 | source_location location; | |
5753 | #else | |
6de9cd9a | 5754 | location_t *locus; |
9506ac2b | 5755 | #endif |
6de9cd9a DN |
5756 | tree last; |
5757 | edge e; | |
628f6a4e | 5758 | edge_iterator ei; |
6de9cd9a | 5759 | |
6de9cd9a DN |
5760 | /* If we have a path to EXIT, then we do return. */ |
5761 | if (TREE_THIS_VOLATILE (cfun->decl) | |
628f6a4e | 5762 | && EDGE_COUNT (EXIT_BLOCK_PTR->preds) > 0) |
6de9cd9a | 5763 | { |
9506ac2b PB |
5764 | #ifdef USE_MAPPED_LOCATION |
5765 | location = UNKNOWN_LOCATION; | |
5766 | #else | |
6de9cd9a | 5767 | locus = NULL; |
9506ac2b | 5768 | #endif |
628f6a4e | 5769 | FOR_EACH_EDGE (e, ei, EXIT_BLOCK_PTR->preds) |
6de9cd9a DN |
5770 | { |
5771 | last = last_stmt (e->src); | |
5772 | if (TREE_CODE (last) == RETURN_EXPR | |
9506ac2b PB |
5773 | #ifdef USE_MAPPED_LOCATION |
5774 | && (location = EXPR_LOCATION (last)) != UNKNOWN_LOCATION) | |
5775 | #else | |
6de9cd9a | 5776 | && (locus = EXPR_LOCUS (last)) != NULL) |
9506ac2b | 5777 | #endif |
6de9cd9a DN |
5778 | break; |
5779 | } | |
9506ac2b PB |
5780 | #ifdef USE_MAPPED_LOCATION |
5781 | if (location == UNKNOWN_LOCATION) | |
5782 | location = cfun->function_end_locus; | |
d4ee4d25 | 5783 | warning (0, "%H%<noreturn%> function does return", &location); |
9506ac2b | 5784 | #else |
6de9cd9a DN |
5785 | if (!locus) |
5786 | locus = &cfun->function_end_locus; | |
d4ee4d25 | 5787 | warning (0, "%H%<noreturn%> function does return", locus); |
9506ac2b | 5788 | #endif |
6de9cd9a DN |
5789 | } |
5790 | ||
5791 | /* If we see "return;" in some basic block, then we do reach the end | |
5792 | without returning a value. */ | |
5793 | else if (warn_return_type | |
089efaa4 | 5794 | && !TREE_NO_WARNING (cfun->decl) |
628f6a4e | 5795 | && EDGE_COUNT (EXIT_BLOCK_PTR->preds) > 0 |
6de9cd9a DN |
5796 | && !VOID_TYPE_P (TREE_TYPE (TREE_TYPE (cfun->decl)))) |
5797 | { | |
628f6a4e | 5798 | FOR_EACH_EDGE (e, ei, EXIT_BLOCK_PTR->preds) |
6de9cd9a DN |
5799 | { |
5800 | tree last = last_stmt (e->src); | |
5801 | if (TREE_CODE (last) == RETURN_EXPR | |
0c9b182b JJ |
5802 | && TREE_OPERAND (last, 0) == NULL |
5803 | && !TREE_NO_WARNING (last)) | |
6de9cd9a | 5804 | { |
9506ac2b PB |
5805 | #ifdef USE_MAPPED_LOCATION |
5806 | location = EXPR_LOCATION (last); | |
5807 | if (location == UNKNOWN_LOCATION) | |
5808 | location = cfun->function_end_locus; | |
d4ee4d25 | 5809 | warning (0, "%Hcontrol reaches end of non-void function", &location); |
9506ac2b | 5810 | #else |
6de9cd9a DN |
5811 | locus = EXPR_LOCUS (last); |
5812 | if (!locus) | |
5813 | locus = &cfun->function_end_locus; | |
d4ee4d25 | 5814 | warning (0, "%Hcontrol reaches end of non-void function", locus); |
9506ac2b | 5815 | #endif |
089efaa4 | 5816 | TREE_NO_WARNING (cfun->decl) = 1; |
6de9cd9a DN |
5817 | break; |
5818 | } | |
5819 | } | |
5820 | } | |
c2924966 | 5821 | return 0; |
6de9cd9a DN |
5822 | } |
5823 | ||
5824 | ||
5825 | /* Given a basic block B which ends with a conditional and has | |
5826 | precisely two successors, determine which of the edges is taken if | |
5827 | the conditional is true and which is taken if the conditional is | |
5828 | false. Set TRUE_EDGE and FALSE_EDGE appropriately. */ | |
5829 | ||
5830 | void | |
5831 | extract_true_false_edges_from_block (basic_block b, | |
5832 | edge *true_edge, | |
5833 | edge *false_edge) | |
5834 | { | |
628f6a4e | 5835 | edge e = EDGE_SUCC (b, 0); |
6de9cd9a DN |
5836 | |
5837 | if (e->flags & EDGE_TRUE_VALUE) | |
5838 | { | |
5839 | *true_edge = e; | |
628f6a4e | 5840 | *false_edge = EDGE_SUCC (b, 1); |
6de9cd9a DN |
5841 | } |
5842 | else | |
5843 | { | |
5844 | *false_edge = e; | |
628f6a4e | 5845 | *true_edge = EDGE_SUCC (b, 1); |
6de9cd9a DN |
5846 | } |
5847 | } | |
5848 | ||
5849 | struct tree_opt_pass pass_warn_function_return = | |
5850 | { | |
5851 | NULL, /* name */ | |
5852 | NULL, /* gate */ | |
5853 | execute_warn_function_return, /* execute */ | |
5854 | NULL, /* sub */ | |
5855 | NULL, /* next */ | |
5856 | 0, /* static_pass_number */ | |
5857 | 0, /* tv_id */ | |
00bfee6f | 5858 | PROP_cfg, /* properties_required */ |
6de9cd9a DN |
5859 | 0, /* properties_provided */ |
5860 | 0, /* properties_destroyed */ | |
5861 | 0, /* todo_flags_start */ | |
9f8628ba PB |
5862 | 0, /* todo_flags_finish */ |
5863 | 0 /* letter */ | |
6de9cd9a | 5864 | }; |
aa313ed4 JH |
5865 | |
5866 | /* Emit noreturn warnings. */ | |
5867 | ||
c2924966 | 5868 | static unsigned int |
aa313ed4 JH |
5869 | execute_warn_function_noreturn (void) |
5870 | { | |
5871 | if (warn_missing_noreturn | |
5872 | && !TREE_THIS_VOLATILE (cfun->decl) | |
5873 | && EDGE_COUNT (EXIT_BLOCK_PTR->preds) == 0 | |
5874 | && !lang_hooks.function.missing_noreturn_ok_p (cfun->decl)) | |
3176a0c2 DD |
5875 | warning (OPT_Wmissing_noreturn, "%Jfunction might be possible candidate " |
5876 | "for attribute %<noreturn%>", | |
aa313ed4 | 5877 | cfun->decl); |
c2924966 | 5878 | return 0; |
aa313ed4 JH |
5879 | } |
5880 | ||
5881 | struct tree_opt_pass pass_warn_function_noreturn = | |
5882 | { | |
5883 | NULL, /* name */ | |
5884 | NULL, /* gate */ | |
5885 | execute_warn_function_noreturn, /* execute */ | |
5886 | NULL, /* sub */ | |
5887 | NULL, /* next */ | |
5888 | 0, /* static_pass_number */ | |
5889 | 0, /* tv_id */ | |
5890 | PROP_cfg, /* properties_required */ | |
5891 | 0, /* properties_provided */ | |
5892 | 0, /* properties_destroyed */ | |
5893 | 0, /* todo_flags_start */ | |
5894 | 0, /* todo_flags_finish */ | |
5895 | 0 /* letter */ | |
5896 | }; |