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b36d64df | 1 | /* Control flow graph manipulation code for GNU compiler. |
3aea1f79 | 2 | Copyright (C) 1987-2014 Free Software Foundation, Inc. |
b36d64df | 3 | |
4 | This file is part of GCC. | |
5 | ||
6 | GCC is free software; you can redistribute it and/or modify it under | |
7 | the terms of the GNU General Public License as published by the Free | |
8c4c00c1 | 8 | Software Foundation; either version 3, or (at your option) any later |
b36d64df | 9 | version. |
10 | ||
11 | GCC is distributed in the hope that it will be useful, but WITHOUT ANY | |
12 | WARRANTY; without even the implied warranty of MERCHANTABILITY or | |
13 | FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License | |
14 | for more details. | |
15 | ||
16 | You should have received a copy of the GNU General Public License | |
8c4c00c1 | 17 | along with GCC; see the file COPYING3. If not see |
18 | <http://www.gnu.org/licenses/>. */ | |
b36d64df | 19 | |
5cc577b6 | 20 | /* This file contains low level functions to manipulate the CFG and analyze it |
21 | that are aware of the RTL intermediate language. | |
b36d64df | 22 | |
23 | Available functionality: | |
c60fa3a7 | 24 | - Basic CFG/RTL manipulation API documented in cfghooks.h |
5cc577b6 | 25 | - CFG-aware instruction chain manipulation |
b36d64df | 26 | delete_insn, delete_insn_chain |
c60fa3a7 | 27 | - Edge splitting and committing to edges |
28 | insert_insn_on_edge, commit_edge_insertions | |
29 | - CFG updating after insn simplification | |
30 | purge_dead_edges, purge_all_dead_edges | |
54f21e20 | 31 | - CFG fixing after coarse manipulation |
32 | fixup_abnormal_edges | |
c60fa3a7 | 33 | |
34 | Functions not supposed for generic use: | |
5cc577b6 | 35 | - Infrastructure to determine quickly basic block for insn |
b36d64df | 36 | compute_bb_for_insn, update_bb_for_insn, set_block_for_insn, |
5cc577b6 | 37 | - Edge redirection with updating and optimizing of insn chain |
c60fa3a7 | 38 | block_label, tidy_fallthru_edge, force_nonfallthru */ |
b36d64df | 39 | \f |
40 | #include "config.h" | |
41 | #include "system.h" | |
805e22b2 | 42 | #include "coretypes.h" |
43 | #include "tm.h" | |
b36d64df | 44 | #include "tree.h" |
b36d64df | 45 | #include "hard-reg-set.h" |
46 | #include "basic-block.h" | |
aa78dca5 | 47 | #include "bb-reorder.h" |
b36d64df | 48 | #include "regs.h" |
49 | #include "flags.h" | |
b36d64df | 50 | #include "function.h" |
51 | #include "except.h" | |
d7091a76 | 52 | #include "rtl-error.h" |
b36d64df | 53 | #include "tm_p.h" |
54 | #include "obstack.h" | |
225e5f6f | 55 | #include "insn-attr.h" |
26fb1781 | 56 | #include "insn-config.h" |
804e497b | 57 | #include "expr.h" |
065efcb1 | 58 | #include "target.h" |
218e3e4e | 59 | #include "common/common-target.h" |
c50ae675 | 60 | #include "cfgloop.h" |
e0dde8f8 | 61 | #include "ggc.h" |
77fce4cd | 62 | #include "tree-pass.h" |
3072d30e | 63 | #include "df.h" |
b36d64df | 64 | |
23a070f3 | 65 | /* Holds the interesting leading and trailing notes for the function. |
66 | Only applicable if the CFG is in cfglayout mode. */ | |
67 | static GTY(()) rtx cfg_layout_function_footer; | |
68 | static GTY(()) rtx cfg_layout_function_header; | |
69 | ||
70 | static rtx skip_insns_after_block (basic_block); | |
71 | static void record_effective_endpoints (void); | |
72 | static rtx label_for_bb (basic_block); | |
73 | static void fixup_reorder_chain (void); | |
74 | ||
75 | void verify_insn_chain (void); | |
76 | static void fixup_fallthru_exit_predecessor (void); | |
5493cb9a | 77 | static int can_delete_note_p (const_rtx); |
78 | static int can_delete_label_p (const_rtx); | |
4c9e08a4 | 79 | static basic_block rtl_split_edge (edge); |
5f5d4cd1 | 80 | static bool rtl_move_block_after (basic_block, basic_block); |
4c9e08a4 | 81 | static int rtl_verify_flow_info (void); |
5f5d4cd1 | 82 | static basic_block cfg_layout_split_block (basic_block, void *); |
4ee9c684 | 83 | static edge cfg_layout_redirect_edge_and_branch (edge, basic_block); |
4c9e08a4 | 84 | static basic_block cfg_layout_redirect_edge_and_branch_force (edge, basic_block); |
85 | static void cfg_layout_delete_block (basic_block); | |
86 | static void rtl_delete_block (basic_block); | |
87 | static basic_block rtl_redirect_edge_and_branch_force (edge, basic_block); | |
4ee9c684 | 88 | static edge rtl_redirect_edge_and_branch (edge, basic_block); |
5f5d4cd1 | 89 | static basic_block rtl_split_block (basic_block, void *); |
5147ec07 | 90 | static void rtl_dump_bb (FILE *, basic_block, int, int); |
4c9e08a4 | 91 | static int rtl_verify_flow_info_1 (void); |
5f5d4cd1 | 92 | static void rtl_make_forwarder_block (edge); |
b36d64df | 93 | \f |
94 | /* Return true if NOTE is not one of the ones that must be kept paired, | |
5cc577b6 | 95 | so that we may simply delete it. */ |
b36d64df | 96 | |
97 | static int | |
5493cb9a | 98 | can_delete_note_p (const_rtx note) |
b36d64df | 99 | { |
25e880b1 | 100 | switch (NOTE_KIND (note)) |
101 | { | |
102 | case NOTE_INSN_DELETED: | |
103 | case NOTE_INSN_BASIC_BLOCK: | |
104 | case NOTE_INSN_EPILOGUE_BEG: | |
105 | return true; | |
106 | ||
107 | default: | |
108 | return false; | |
109 | } | |
b36d64df | 110 | } |
111 | ||
112 | /* True if a given label can be deleted. */ | |
113 | ||
114 | static int | |
5493cb9a | 115 | can_delete_label_p (const_rtx label) |
b36d64df | 116 | { |
5cc577b6 | 117 | return (!LABEL_PRESERVE_P (label) |
118 | /* User declared labels must be preserved. */ | |
119 | && LABEL_NAME (label) == 0 | |
2f138c1c | 120 | && !in_expr_list_p (forced_labels, label)); |
b36d64df | 121 | } |
122 | ||
a2b85e40 | 123 | /* Delete INSN by patching it out. */ |
b36d64df | 124 | |
a2b85e40 | 125 | void |
4c9e08a4 | 126 | delete_insn (rtx insn) |
b36d64df | 127 | { |
b36d64df | 128 | rtx note; |
129 | bool really_delete = true; | |
130 | ||
6d7dc5b9 | 131 | if (LABEL_P (insn)) |
b36d64df | 132 | { |
133 | /* Some labels can't be directly removed from the INSN chain, as they | |
a0c938f0 | 134 | might be references via variables, constant pool etc. |
135 | Convert them to the special NOTE_INSN_DELETED_LABEL note. */ | |
b36d64df | 136 | if (! can_delete_label_p (insn)) |
137 | { | |
138 | const char *name = LABEL_NAME (insn); | |
6de7acd5 | 139 | basic_block bb = BLOCK_FOR_INSN (insn); |
a2b85e40 | 140 | rtx bb_note = NEXT_INSN (insn); |
b36d64df | 141 | |
142 | really_delete = false; | |
143 | PUT_CODE (insn, NOTE); | |
ad4583d9 | 144 | NOTE_KIND (insn) = NOTE_INSN_DELETED_LABEL; |
7bd3dcc4 | 145 | NOTE_DELETED_LABEL_NAME (insn) = name; |
a2b85e40 | 146 | |
fb848efb | 147 | /* If the note following the label starts a basic block, and the |
6de7acd5 | 148 | label is a member of the same basic block, interchange the two. */ |
fb848efb | 149 | if (bb_note != NULL_RTX |
150 | && NOTE_INSN_BASIC_BLOCK_P (bb_note) | |
6de7acd5 | 151 | && bb != NULL |
152 | && bb == BLOCK_FOR_INSN (bb_note)) | |
a2b85e40 | 153 | { |
154 | reorder_insns_nobb (insn, insn, bb_note); | |
155 | BB_HEAD (bb) = bb_note; | |
156 | if (BB_END (bb) == bb_note) | |
157 | BB_END (bb) = insn; | |
158 | } | |
b36d64df | 159 | } |
5cc577b6 | 160 | |
b36d64df | 161 | remove_node_from_expr_list (insn, &nonlocal_goto_handler_labels); |
162 | } | |
163 | ||
164 | if (really_delete) | |
165 | { | |
e172357f | 166 | /* If this insn has already been deleted, something is very wrong. */ |
cc636d56 | 167 | gcc_assert (!INSN_DELETED_P (insn)); |
93ff53d3 | 168 | if (INSN_P (insn)) |
169 | df_insn_delete (insn); | |
b36d64df | 170 | remove_insn (insn); |
171 | INSN_DELETED_P (insn) = 1; | |
172 | } | |
173 | ||
174 | /* If deleting a jump, decrement the use count of the label. Deleting | |
175 | the label itself should happen in the normal course of block merging. */ | |
19d2fe05 | 176 | if (JUMP_P (insn)) |
242dafee | 177 | { |
19d2fe05 | 178 | if (JUMP_LABEL (insn) |
179 | && LABEL_P (JUMP_LABEL (insn))) | |
180 | LABEL_NUSES (JUMP_LABEL (insn))--; | |
181 | ||
182 | /* If there are more targets, remove them too. */ | |
183 | while ((note | |
184 | = find_reg_note (insn, REG_LABEL_TARGET, NULL_RTX)) != NULL_RTX | |
6d7dc5b9 | 185 | && LABEL_P (XEXP (note, 0))) |
242dafee | 186 | { |
187 | LABEL_NUSES (XEXP (note, 0))--; | |
188 | remove_note (insn, note); | |
189 | } | |
190 | } | |
b36d64df | 191 | |
19d2fe05 | 192 | /* Also if deleting any insn that references a label as an operand. */ |
193 | while ((note = find_reg_note (insn, REG_LABEL_OPERAND, NULL_RTX)) != NULL_RTX | |
194 | && LABEL_P (XEXP (note, 0))) | |
195 | { | |
196 | LABEL_NUSES (XEXP (note, 0))--; | |
197 | remove_note (insn, note); | |
198 | } | |
199 | ||
971ba038 | 200 | if (JUMP_TABLE_DATA_P (insn)) |
b36d64df | 201 | { |
202 | rtx pat = PATTERN (insn); | |
203 | int diff_vec_p = GET_CODE (PATTERN (insn)) == ADDR_DIFF_VEC; | |
204 | int len = XVECLEN (pat, diff_vec_p); | |
205 | int i; | |
206 | ||
207 | for (i = 0; i < len; i++) | |
fd0d7f8c | 208 | { |
209 | rtx label = XEXP (XVECEXP (pat, diff_vec_p, i), 0); | |
210 | ||
211 | /* When deleting code in bulk (e.g. removing many unreachable | |
212 | blocks) we can delete a label that's a target of the vector | |
213 | before deleting the vector itself. */ | |
6d7dc5b9 | 214 | if (!NOTE_P (label)) |
fd0d7f8c | 215 | LABEL_NUSES (label)--; |
216 | } | |
b36d64df | 217 | } |
b36d64df | 218 | } |
219 | ||
fb20d6fa | 220 | /* Like delete_insn but also purge dead edges from BB. */ |
ebc94641 | 221 | |
a2b85e40 | 222 | void |
4c9e08a4 | 223 | delete_insn_and_edges (rtx insn) |
fb20d6fa | 224 | { |
fb20d6fa | 225 | bool purge = false; |
226 | ||
ab87d1bc | 227 | if (INSN_P (insn) |
fb20d6fa | 228 | && BLOCK_FOR_INSN (insn) |
5496dbfc | 229 | && BB_END (BLOCK_FOR_INSN (insn)) == insn) |
fb20d6fa | 230 | purge = true; |
a2b85e40 | 231 | delete_insn (insn); |
fb20d6fa | 232 | if (purge) |
233 | purge_dead_edges (BLOCK_FOR_INSN (insn)); | |
fb20d6fa | 234 | } |
235 | ||
b36d64df | 236 | /* Unlink a chain of insns between START and FINISH, leaving notes |
39257eb5 | 237 | that must be paired. If CLEAR_BB is true, we set bb field for |
238 | insns that cannot be removed to NULL. */ | |
b36d64df | 239 | |
240 | void | |
39257eb5 | 241 | delete_insn_chain (rtx start, rtx finish, bool clear_bb) |
b36d64df | 242 | { |
a2b85e40 | 243 | rtx prev, current; |
b36d64df | 244 | |
5cc577b6 | 245 | /* Unchain the insns one by one. It would be quicker to delete all of these |
246 | with a single unchaining, rather than one at a time, but we need to keep | |
247 | the NOTE's. */ | |
a2b85e40 | 248 | current = finish; |
b36d64df | 249 | while (1) |
250 | { | |
a2b85e40 | 251 | prev = PREV_INSN (current); |
252 | if (NOTE_P (current) && !can_delete_note_p (current)) | |
b36d64df | 253 | ; |
254 | else | |
a2b85e40 | 255 | delete_insn (current); |
b36d64df | 256 | |
a2b85e40 | 257 | if (clear_bb && !INSN_DELETED_P (current)) |
258 | set_block_for_insn (current, NULL); | |
39257eb5 | 259 | |
a2b85e40 | 260 | if (current == start) |
b36d64df | 261 | break; |
a2b85e40 | 262 | current = prev; |
b36d64df | 263 | } |
264 | } | |
265 | \f | |
5cc577b6 | 266 | /* Create a new basic block consisting of the instructions between HEAD and END |
267 | inclusive. This function is designed to allow fast BB construction - reuses | |
268 | the note and basic block struct in BB_NOTE, if any and do not grow | |
269 | BASIC_BLOCK chain and should be used directly only by CFG construction code. | |
270 | END can be NULL in to create new empty basic block before HEAD. Both END | |
7fa55aef | 271 | and HEAD can be NULL to create basic block at the end of INSN chain. |
272 | AFTER is the basic block we should be put after. */ | |
b36d64df | 273 | |
274 | basic_block | |
4c9e08a4 | 275 | create_basic_block_structure (rtx head, rtx end, rtx bb_note, basic_block after) |
b36d64df | 276 | { |
277 | basic_block bb; | |
278 | ||
279 | if (bb_note | |
b36d64df | 280 | && (bb = NOTE_BASIC_BLOCK (bb_note)) != NULL |
281 | && bb->aux == NULL) | |
282 | { | |
283 | /* If we found an existing note, thread it back onto the chain. */ | |
284 | ||
285 | rtx after; | |
286 | ||
6d7dc5b9 | 287 | if (LABEL_P (head)) |
b36d64df | 288 | after = head; |
289 | else | |
290 | { | |
291 | after = PREV_INSN (head); | |
292 | head = bb_note; | |
293 | } | |
294 | ||
295 | if (after != bb_note && NEXT_INSN (after) != bb_note) | |
ab87d1bc | 296 | reorder_insns_nobb (bb_note, bb_note, after); |
b36d64df | 297 | } |
298 | else | |
299 | { | |
300 | /* Otherwise we must create a note and a basic block structure. */ | |
301 | ||
302 | bb = alloc_block (); | |
303 | ||
e0dde8f8 | 304 | init_rtl_bb_info (bb); |
b36d64df | 305 | if (!head && !end) |
5cc577b6 | 306 | head = end = bb_note |
307 | = emit_note_after (NOTE_INSN_BASIC_BLOCK, get_last_insn ()); | |
6d7dc5b9 | 308 | else if (LABEL_P (head) && end) |
b36d64df | 309 | { |
310 | bb_note = emit_note_after (NOTE_INSN_BASIC_BLOCK, head); | |
311 | if (head == end) | |
312 | end = bb_note; | |
313 | } | |
314 | else | |
315 | { | |
316 | bb_note = emit_note_before (NOTE_INSN_BASIC_BLOCK, head); | |
317 | head = bb_note; | |
318 | if (!end) | |
319 | end = head; | |
320 | } | |
5cc577b6 | 321 | |
b36d64df | 322 | NOTE_BASIC_BLOCK (bb_note) = bb; |
323 | } | |
324 | ||
325 | /* Always include the bb note in the block. */ | |
326 | if (NEXT_INSN (end) == bb_note) | |
327 | end = bb_note; | |
328 | ||
5496dbfc | 329 | BB_HEAD (bb) = head; |
330 | BB_END (bb) = end; | |
fe672ac0 | 331 | bb->index = last_basic_block_for_fn (cfun)++; |
e0dde8f8 | 332 | bb->flags = BB_NEW | BB_RTL; |
7fa55aef | 333 | link_block (bb, after); |
f64d2ca4 | 334 | SET_BASIC_BLOCK_FOR_FN (cfun, bb->index, bb); |
3072d30e | 335 | df_bb_refs_record (bb->index, false); |
ab87d1bc | 336 | update_bb_for_insn (bb); |
7562ed74 | 337 | BB_SET_PARTITION (bb, BB_UNPARTITIONED); |
b36d64df | 338 | |
339 | /* Tag the block so that we know it has been used when considering | |
340 | other basic block notes. */ | |
341 | bb->aux = bb; | |
342 | ||
343 | return bb; | |
344 | } | |
345 | ||
5cc577b6 | 346 | /* Create new basic block consisting of instructions in between HEAD and END |
0a55d497 | 347 | and place it to the BB chain after block AFTER. END can be NULL to |
348 | create a new empty basic block before HEAD. Both END and HEAD can be | |
349 | NULL to create basic block at the end of INSN chain. */ | |
b36d64df | 350 | |
c60fa3a7 | 351 | static basic_block |
352 | rtl_create_basic_block (void *headp, void *endp, basic_block after) | |
b36d64df | 353 | { |
f780cc25 | 354 | rtx head = (rtx) headp, end = (rtx) endp; |
b36d64df | 355 | basic_block bb; |
b3d6de89 | 356 | |
743ff5bb | 357 | /* Grow the basic block array if needed. */ |
fe672ac0 | 358 | if ((size_t) last_basic_block_for_fn (cfun) |
359 | >= basic_block_info_for_fn (cfun)->length ()) | |
743ff5bb | 360 | { |
fe672ac0 | 361 | size_t new_size = |
362 | (last_basic_block_for_fn (cfun) | |
363 | + (last_basic_block_for_fn (cfun) + 3) / 4); | |
9ca41bd1 | 364 | vec_safe_grow_cleared (basic_block_info_for_fn (cfun), new_size); |
743ff5bb | 365 | } |
b3d6de89 | 366 | |
a28770e1 | 367 | n_basic_blocks_for_fn (cfun)++; |
b36d64df | 368 | |
f23d9a22 | 369 | bb = create_basic_block_structure (head, end, NULL, after); |
b36d64df | 370 | bb->aux = NULL; |
371 | return bb; | |
372 | } | |
c60fa3a7 | 373 | |
374 | static basic_block | |
375 | cfg_layout_create_basic_block (void *head, void *end, basic_block after) | |
376 | { | |
377 | basic_block newbb = rtl_create_basic_block (head, end, after); | |
378 | ||
c60fa3a7 | 379 | return newbb; |
380 | } | |
b36d64df | 381 | \f |
382 | /* Delete the insns in a (non-live) block. We physically delete every | |
383 | non-deleted-note insn, and update the flow graph appropriately. | |
384 | ||
385 | Return nonzero if we deleted an exception handler. */ | |
386 | ||
387 | /* ??? Preserving all such notes strikes me as wrong. It would be nice | |
388 | to post-process the stream to remove empty blocks, loops, ranges, etc. */ | |
389 | ||
5f704f9f | 390 | static void |
4c9e08a4 | 391 | rtl_delete_block (basic_block b) |
b36d64df | 392 | { |
5d65a39c | 393 | rtx insn, end; |
b36d64df | 394 | |
395 | /* If the head of this block is a CODE_LABEL, then it might be the | |
57548910 | 396 | label for an exception handler which can't be reached. We need |
397 | to remove the label from the exception_handler_label list. */ | |
5496dbfc | 398 | insn = BB_HEAD (b); |
b36d64df | 399 | |
5d65a39c | 400 | end = get_last_bb_insn (b); |
b36d64df | 401 | |
402 | /* Selectively delete the entire chain. */ | |
5496dbfc | 403 | BB_HEAD (b) = NULL; |
39257eb5 | 404 | delete_insn_chain (insn, end, true); |
405 | ||
3072d30e | 406 | |
407 | if (dump_file) | |
408 | fprintf (dump_file, "deleting block %d\n", b->index); | |
409 | df_bb_delete (b->index); | |
b36d64df | 410 | } |
411 | \f | |
f23d9a22 | 412 | /* Records the basic block struct in BLOCK_FOR_INSN for every insn. */ |
b36d64df | 413 | |
414 | void | |
4c9e08a4 | 415 | compute_bb_for_insn (void) |
b36d64df | 416 | { |
4c26117a | 417 | basic_block bb; |
b36d64df | 418 | |
fc00614f | 419 | FOR_EACH_BB_FN (bb, cfun) |
b36d64df | 420 | { |
5496dbfc | 421 | rtx end = BB_END (bb); |
5cc577b6 | 422 | rtx insn; |
b36d64df | 423 | |
5496dbfc | 424 | for (insn = BB_HEAD (bb); ; insn = NEXT_INSN (insn)) |
b36d64df | 425 | { |
ab87d1bc | 426 | BLOCK_FOR_INSN (insn) = bb; |
b36d64df | 427 | if (insn == end) |
428 | break; | |
b36d64df | 429 | } |
430 | } | |
431 | } | |
432 | ||
433 | /* Release the basic_block_for_insn array. */ | |
434 | ||
2a1990e9 | 435 | unsigned int |
4c9e08a4 | 436 | free_bb_for_insn (void) |
b36d64df | 437 | { |
ab87d1bc | 438 | rtx insn; |
439 | for (insn = get_insns (); insn; insn = NEXT_INSN (insn)) | |
6d7dc5b9 | 440 | if (!BARRIER_P (insn)) |
ab87d1bc | 441 | BLOCK_FOR_INSN (insn) = NULL; |
2a1990e9 | 442 | return 0; |
b36d64df | 443 | } |
444 | ||
cbe8bda8 | 445 | namespace { |
446 | ||
447 | const pass_data pass_data_free_cfg = | |
448 | { | |
449 | RTL_PASS, /* type */ | |
450 | "*free_cfg", /* name */ | |
451 | OPTGROUP_NONE, /* optinfo_flags */ | |
cbe8bda8 | 452 | true, /* has_execute */ |
453 | TV_NONE, /* tv_id */ | |
454 | 0, /* properties_required */ | |
455 | 0, /* properties_provided */ | |
456 | PROP_cfg, /* properties_destroyed */ | |
457 | 0, /* todo_flags_start */ | |
458 | 0, /* todo_flags_finish */ | |
77fce4cd | 459 | }; |
460 | ||
cbe8bda8 | 461 | class pass_free_cfg : public rtl_opt_pass |
462 | { | |
463 | public: | |
9af5ce0c | 464 | pass_free_cfg (gcc::context *ctxt) |
465 | : rtl_opt_pass (pass_data_free_cfg, ctxt) | |
cbe8bda8 | 466 | {} |
467 | ||
468 | /* opt_pass methods: */ | |
65b0537f | 469 | virtual unsigned int execute (function *); |
cbe8bda8 | 470 | |
471 | }; // class pass_free_cfg | |
472 | ||
65b0537f | 473 | unsigned int |
474 | pass_free_cfg::execute (function *) | |
475 | { | |
476 | #ifdef DELAY_SLOTS | |
477 | /* The resource.c machinery uses DF but the CFG isn't guaranteed to be | |
478 | valid at that point so it would be too late to call df_analyze. */ | |
479 | if (optimize > 0 && flag_delayed_branch) | |
480 | { | |
481 | df_note_add_problem (); | |
482 | df_analyze (); | |
483 | } | |
484 | #endif | |
485 | ||
486 | if (crtl->has_bb_partition) | |
487 | insert_section_boundary_note (); | |
488 | ||
489 | free_bb_for_insn (); | |
490 | return 0; | |
491 | } | |
492 | ||
cbe8bda8 | 493 | } // anon namespace |
494 | ||
495 | rtl_opt_pass * | |
496 | make_pass_free_cfg (gcc::context *ctxt) | |
497 | { | |
498 | return new pass_free_cfg (ctxt); | |
499 | } | |
500 | ||
a0fee14a | 501 | /* Return RTX to emit after when we want to emit code on the entry of function. */ |
502 | rtx | |
503 | entry_of_function (void) | |
504 | { | |
a28770e1 | 505 | return (n_basic_blocks_for_fn (cfun) > NUM_FIXED_BLOCKS ? |
34154e27 | 506 | BB_HEAD (ENTRY_BLOCK_PTR_FOR_FN (cfun)->next_bb) : get_insns ()); |
a0fee14a | 507 | } |
508 | ||
aa02fa19 | 509 | /* Emit INSN at the entry point of the function, ensuring that it is only |
510 | executed once per function. */ | |
511 | void | |
512 | emit_insn_at_entry (rtx insn) | |
513 | { | |
34154e27 | 514 | edge_iterator ei = ei_start (ENTRY_BLOCK_PTR_FOR_FN (cfun)->succs); |
aa02fa19 | 515 | edge e = ei_safe_edge (ei); |
1db61145 | 516 | gcc_assert (e->flags & EDGE_FALLTHRU); |
aa02fa19 | 517 | |
518 | insert_insn_on_edge (insn, e); | |
519 | commit_edge_insertions (); | |
520 | } | |
521 | ||
f41d4683 | 522 | /* Update BLOCK_FOR_INSN of insns between BEGIN and END |
48e1416a | 523 | (or BARRIER if found) and notify df of the bb change. |
f41d4683 | 524 | The insn chain range is inclusive |
525 | (i.e. both BEGIN and END will be updated. */ | |
b36d64df | 526 | |
f41d4683 | 527 | static void |
528 | update_bb_for_insn_chain (rtx begin, rtx end, basic_block bb) | |
b36d64df | 529 | { |
530 | rtx insn; | |
531 | ||
f41d4683 | 532 | end = NEXT_INSN (end); |
533 | for (insn = begin; insn != end; insn = NEXT_INSN (insn)) | |
a2bdd643 | 534 | if (!BARRIER_P (insn)) |
535 | df_insn_change_bb (insn, bb); | |
b36d64df | 536 | } |
f41d4683 | 537 | |
538 | /* Update BLOCK_FOR_INSN of insns in BB to BB, | |
539 | and notify df of the change. */ | |
540 | ||
541 | void | |
542 | update_bb_for_insn (basic_block bb) | |
543 | { | |
544 | update_bb_for_insn_chain (BB_HEAD (bb), BB_END (bb), bb); | |
545 | } | |
546 | ||
4a020a8c | 547 | \f |
548 | /* Like active_insn_p, except keep the return value clobber around | |
549 | even after reload. */ | |
550 | ||
551 | static bool | |
552 | flow_active_insn_p (const_rtx insn) | |
553 | { | |
554 | if (active_insn_p (insn)) | |
555 | return true; | |
556 | ||
557 | /* A clobber of the function return value exists for buggy | |
558 | programs that fail to return a value. Its effect is to | |
559 | keep the return value from being live across the entire | |
560 | function. If we allow it to be skipped, we introduce the | |
561 | possibility for register lifetime confusion. */ | |
562 | if (GET_CODE (PATTERN (insn)) == CLOBBER | |
563 | && REG_P (XEXP (PATTERN (insn), 0)) | |
564 | && REG_FUNCTION_VALUE_P (XEXP (PATTERN (insn), 0))) | |
565 | return true; | |
566 | ||
567 | return false; | |
568 | } | |
569 | ||
570 | /* Return true if the block has no effect and only forwards control flow to | |
571 | its single destination. */ | |
4a020a8c | 572 | |
573 | bool | |
bbdfcf34 | 574 | contains_no_active_insn_p (const_basic_block bb) |
4a020a8c | 575 | { |
576 | rtx insn; | |
577 | ||
34154e27 | 578 | if (bb == EXIT_BLOCK_PTR_FOR_FN (cfun) || bb == ENTRY_BLOCK_PTR_FOR_FN (cfun) |
4a020a8c | 579 | || !single_succ_p (bb)) |
580 | return false; | |
581 | ||
bbdfcf34 | 582 | for (insn = BB_HEAD (bb); insn != BB_END (bb); insn = NEXT_INSN (insn)) |
583 | if (INSN_P (insn) && flow_active_insn_p (insn)) | |
584 | return false; | |
585 | ||
586 | return (!INSN_P (insn) | |
587 | || (JUMP_P (insn) && simplejump_p (insn)) | |
588 | || !flow_active_insn_p (insn)); | |
589 | } | |
590 | ||
591 | /* Likewise, but protect loop latches, headers and preheaders. */ | |
592 | /* FIXME: Make this a cfg hook. */ | |
593 | ||
594 | bool | |
595 | forwarder_block_p (const_basic_block bb) | |
596 | { | |
597 | if (!contains_no_active_insn_p (bb)) | |
598 | return false; | |
599 | ||
4a020a8c | 600 | /* Protect loop latches, headers and preheaders. */ |
601 | if (current_loops) | |
602 | { | |
603 | basic_block dest; | |
604 | if (bb->loop_father->header == bb) | |
605 | return false; | |
606 | dest = EDGE_SUCC (bb, 0)->dest; | |
607 | if (dest->loop_father->header == dest) | |
608 | return false; | |
609 | } | |
610 | ||
bbdfcf34 | 611 | return true; |
4a020a8c | 612 | } |
613 | ||
614 | /* Return nonzero if we can reach target from src by falling through. */ | |
cd316116 | 615 | /* FIXME: Make this a cfg hook, the result is only valid in cfgrtl mode. */ |
4a020a8c | 616 | |
617 | bool | |
618 | can_fallthru (basic_block src, basic_block target) | |
619 | { | |
620 | rtx insn = BB_END (src); | |
621 | rtx insn2; | |
622 | edge e; | |
623 | edge_iterator ei; | |
624 | ||
34154e27 | 625 | if (target == EXIT_BLOCK_PTR_FOR_FN (cfun)) |
4a020a8c | 626 | return true; |
627 | if (src->next_bb != target) | |
cd316116 | 628 | return false; |
629 | ||
630 | /* ??? Later we may add code to move jump tables offline. */ | |
631 | if (tablejump_p (insn, NULL, NULL)) | |
632 | return false; | |
633 | ||
4a020a8c | 634 | FOR_EACH_EDGE (e, ei, src->succs) |
34154e27 | 635 | if (e->dest == EXIT_BLOCK_PTR_FOR_FN (cfun) |
4a020a8c | 636 | && e->flags & EDGE_FALLTHRU) |
cd316116 | 637 | return false; |
4a020a8c | 638 | |
639 | insn2 = BB_HEAD (target); | |
cd316116 | 640 | if (!active_insn_p (insn2)) |
4a020a8c | 641 | insn2 = next_active_insn (insn2); |
642 | ||
4a020a8c | 643 | return next_active_insn (insn) == insn2; |
644 | } | |
645 | ||
646 | /* Return nonzero if we could reach target from src by falling through, | |
647 | if the target was made adjacent. If we already have a fall-through | |
648 | edge to the exit block, we can't do that. */ | |
649 | static bool | |
650 | could_fall_through (basic_block src, basic_block target) | |
651 | { | |
652 | edge e; | |
653 | edge_iterator ei; | |
654 | ||
34154e27 | 655 | if (target == EXIT_BLOCK_PTR_FOR_FN (cfun)) |
4a020a8c | 656 | return true; |
657 | FOR_EACH_EDGE (e, ei, src->succs) | |
34154e27 | 658 | if (e->dest == EXIT_BLOCK_PTR_FOR_FN (cfun) |
4a020a8c | 659 | && e->flags & EDGE_FALLTHRU) |
660 | return 0; | |
661 | return true; | |
662 | } | |
b36d64df | 663 | \f |
018f0595 | 664 | /* Return the NOTE_INSN_BASIC_BLOCK of BB. */ |
665 | rtx | |
666 | bb_note (basic_block bb) | |
667 | { | |
668 | rtx note; | |
669 | ||
670 | note = BB_HEAD (bb); | |
671 | if (LABEL_P (note)) | |
672 | note = NEXT_INSN (note); | |
673 | ||
674 | gcc_assert (NOTE_INSN_BASIC_BLOCK_P (note)); | |
675 | return note; | |
676 | } | |
677 | ||
3072d30e | 678 | /* Return the INSN immediately following the NOTE_INSN_BASIC_BLOCK |
679 | note associated with the BLOCK. */ | |
680 | ||
681 | static rtx | |
682 | first_insn_after_basic_block_note (basic_block block) | |
683 | { | |
684 | rtx insn; | |
685 | ||
686 | /* Get the first instruction in the block. */ | |
687 | insn = BB_HEAD (block); | |
688 | ||
689 | if (insn == NULL_RTX) | |
690 | return NULL_RTX; | |
691 | if (LABEL_P (insn)) | |
692 | insn = NEXT_INSN (insn); | |
693 | gcc_assert (NOTE_INSN_BASIC_BLOCK_P (insn)); | |
694 | ||
695 | return NEXT_INSN (insn); | |
696 | } | |
697 | ||
5f5d4cd1 | 698 | /* Creates a new basic block just after basic block B by splitting |
699 | everything after specified instruction I. */ | |
b36d64df | 700 | |
5f5d4cd1 | 701 | static basic_block |
4c9e08a4 | 702 | rtl_split_block (basic_block bb, void *insnp) |
b36d64df | 703 | { |
704 | basic_block new_bb; | |
f780cc25 | 705 | rtx insn = (rtx) insnp; |
5f5d4cd1 | 706 | edge e; |
cd665a06 | 707 | edge_iterator ei; |
b36d64df | 708 | |
5f5d4cd1 | 709 | if (!insn) |
710 | { | |
711 | insn = first_insn_after_basic_block_note (bb); | |
712 | ||
713 | if (insn) | |
9845d120 | 714 | { |
715 | rtx next = insn; | |
716 | ||
717 | insn = PREV_INSN (insn); | |
718 | ||
719 | /* If the block contains only debug insns, insn would have | |
720 | been NULL in a non-debug compilation, and then we'd end | |
721 | up emitting a DELETED note. For -fcompare-debug | |
722 | stability, emit the note too. */ | |
723 | if (insn != BB_END (bb) | |
724 | && DEBUG_INSN_P (next) | |
725 | && DEBUG_INSN_P (BB_END (bb))) | |
726 | { | |
727 | while (next != BB_END (bb) && DEBUG_INSN_P (next)) | |
728 | next = NEXT_INSN (next); | |
729 | ||
730 | if (next == BB_END (bb)) | |
731 | emit_note_after (NOTE_INSN_DELETED, next); | |
732 | } | |
733 | } | |
5f5d4cd1 | 734 | else |
735 | insn = get_last_insn (); | |
736 | } | |
737 | ||
738 | /* We probably should check type of the insn so that we do not create | |
739 | inconsistent cfg. It is checked in verify_flow_info anyway, so do not | |
740 | bother. */ | |
741 | if (insn == BB_END (bb)) | |
742 | emit_note_after (NOTE_INSN_DELETED, insn); | |
b36d64df | 743 | |
744 | /* Create the new basic block. */ | |
5496dbfc | 745 | new_bb = create_basic_block (NEXT_INSN (insn), BB_END (bb), bb); |
7562ed74 | 746 | BB_COPY_PARTITION (new_bb, bb); |
5496dbfc | 747 | BB_END (bb) = insn; |
b36d64df | 748 | |
749 | /* Redirect the outgoing edges. */ | |
cd665a06 | 750 | new_bb->succs = bb->succs; |
751 | bb->succs = NULL; | |
752 | FOR_EACH_EDGE (e, ei, new_bb->succs) | |
b36d64df | 753 | e->src = new_bb; |
754 | ||
3072d30e | 755 | /* The new block starts off being dirty. */ |
756 | df_set_bb_dirty (bb); | |
5f5d4cd1 | 757 | return new_bb; |
c60fa3a7 | 758 | } |
759 | ||
8ddad41d | 760 | /* Return true if the single edge between blocks A and B is the only place |
761 | in RTL which holds some unique locus. */ | |
762 | ||
763 | static bool | |
764 | unique_locus_on_edge_between_p (basic_block a, basic_block b) | |
765 | { | |
5169661d | 766 | const location_t goto_locus = EDGE_SUCC (a, 0)->goto_locus; |
8ddad41d | 767 | rtx insn, end; |
768 | ||
8e7408e3 | 769 | if (LOCATION_LOCUS (goto_locus) == UNKNOWN_LOCATION) |
8ddad41d | 770 | return false; |
771 | ||
772 | /* First scan block A backward. */ | |
773 | insn = BB_END (a); | |
774 | end = PREV_INSN (BB_HEAD (a)); | |
5169661d | 775 | while (insn != end && (!NONDEBUG_INSN_P (insn) || !INSN_HAS_LOCATION (insn))) |
8ddad41d | 776 | insn = PREV_INSN (insn); |
777 | ||
5169661d | 778 | if (insn != end && INSN_LOCATION (insn) == goto_locus) |
8ddad41d | 779 | return false; |
780 | ||
781 | /* Then scan block B forward. */ | |
782 | insn = BB_HEAD (b); | |
783 | if (insn) | |
784 | { | |
785 | end = NEXT_INSN (BB_END (b)); | |
786 | while (insn != end && !NONDEBUG_INSN_P (insn)) | |
787 | insn = NEXT_INSN (insn); | |
788 | ||
5169661d | 789 | if (insn != end && INSN_HAS_LOCATION (insn) |
790 | && INSN_LOCATION (insn) == goto_locus) | |
8ddad41d | 791 | return false; |
792 | } | |
793 | ||
794 | return true; | |
795 | } | |
796 | ||
797 | /* If the single edge between blocks A and B is the only place in RTL which | |
798 | holds some unique locus, emit a nop with that locus between the blocks. */ | |
799 | ||
800 | static void | |
801 | emit_nop_for_unique_locus_between (basic_block a, basic_block b) | |
802 | { | |
803 | if (!unique_locus_on_edge_between_p (a, b)) | |
804 | return; | |
805 | ||
806 | BB_END (a) = emit_insn_after_noloc (gen_nop (), BB_END (a), a); | |
5169661d | 807 | INSN_LOCATION (BB_END (a)) = EDGE_SUCC (a, 0)->goto_locus; |
8ddad41d | 808 | } |
809 | ||
b36d64df | 810 | /* Blocks A and B are to be merged into a single block A. The insns |
c60fa3a7 | 811 | are already contiguous. */ |
b36d64df | 812 | |
c60fa3a7 | 813 | static void |
814 | rtl_merge_blocks (basic_block a, basic_block b) | |
b36d64df | 815 | { |
5496dbfc | 816 | rtx b_head = BB_HEAD (b), b_end = BB_END (b), a_end = BB_END (a); |
b36d64df | 817 | rtx del_first = NULL_RTX, del_last = NULL_RTX; |
9845d120 | 818 | rtx b_debug_start = b_end, b_debug_end = b_end; |
18b762f0 | 819 | bool forwarder_p = (b->flags & BB_FORWARDER_BLOCK) != 0; |
b36d64df | 820 | int b_empty = 0; |
821 | ||
3072d30e | 822 | if (dump_file) |
18b762f0 | 823 | fprintf (dump_file, "Merging block %d into block %d...\n", b->index, |
824 | a->index); | |
3072d30e | 825 | |
9845d120 | 826 | while (DEBUG_INSN_P (b_end)) |
827 | b_end = PREV_INSN (b_debug_start = b_end); | |
828 | ||
b36d64df | 829 | /* If there was a CODE_LABEL beginning B, delete it. */ |
6d7dc5b9 | 830 | if (LABEL_P (b_head)) |
b36d64df | 831 | { |
832 | /* Detect basic blocks with nothing but a label. This can happen | |
833 | in particular at the end of a function. */ | |
834 | if (b_head == b_end) | |
835 | b_empty = 1; | |
5cc577b6 | 836 | |
b36d64df | 837 | del_first = del_last = b_head; |
838 | b_head = NEXT_INSN (b_head); | |
839 | } | |
840 | ||
5cc577b6 | 841 | /* Delete the basic block note and handle blocks containing just that |
842 | note. */ | |
b36d64df | 843 | if (NOTE_INSN_BASIC_BLOCK_P (b_head)) |
844 | { | |
845 | if (b_head == b_end) | |
846 | b_empty = 1; | |
847 | if (! del_last) | |
848 | del_first = b_head; | |
5cc577b6 | 849 | |
b36d64df | 850 | del_last = b_head; |
851 | b_head = NEXT_INSN (b_head); | |
852 | } | |
853 | ||
854 | /* If there was a jump out of A, delete it. */ | |
6d7dc5b9 | 855 | if (JUMP_P (a_end)) |
b36d64df | 856 | { |
857 | rtx prev; | |
858 | ||
859 | for (prev = PREV_INSN (a_end); ; prev = PREV_INSN (prev)) | |
6d7dc5b9 | 860 | if (!NOTE_P (prev) |
ad4583d9 | 861 | || NOTE_INSN_BASIC_BLOCK_P (prev) |
5496dbfc | 862 | || prev == BB_HEAD (a)) |
b36d64df | 863 | break; |
864 | ||
865 | del_first = a_end; | |
866 | ||
867 | #ifdef HAVE_cc0 | |
868 | /* If this was a conditional jump, we need to also delete | |
869 | the insn that set cc0. */ | |
870 | if (only_sets_cc0_p (prev)) | |
871 | { | |
872 | rtx tmp = prev; | |
5cc577b6 | 873 | |
b36d64df | 874 | prev = prev_nonnote_insn (prev); |
875 | if (!prev) | |
5496dbfc | 876 | prev = BB_HEAD (a); |
b36d64df | 877 | del_first = tmp; |
878 | } | |
879 | #endif | |
880 | ||
881 | a_end = PREV_INSN (del_first); | |
882 | } | |
6d7dc5b9 | 883 | else if (BARRIER_P (NEXT_INSN (a_end))) |
b36d64df | 884 | del_first = NEXT_INSN (a_end); |
885 | ||
b36d64df | 886 | /* Delete everything marked above as well as crap that might be |
887 | hanging out between the two blocks. */ | |
8ddad41d | 888 | BB_END (a) = a_end; |
889 | BB_HEAD (b) = b_empty ? NULL_RTX : b_head; | |
39257eb5 | 890 | delete_insn_chain (del_first, del_last, true); |
b36d64df | 891 | |
36ebb5b6 | 892 | /* When not optimizing and the edge is the only place in RTL which holds |
8ddad41d | 893 | some unique locus, emit a nop with that locus in between. */ |
894 | if (!optimize) | |
895 | { | |
896 | emit_nop_for_unique_locus_between (a, b); | |
897 | a_end = BB_END (a); | |
898 | } | |
899 | ||
b36d64df | 900 | /* Reassociate the insns of B with A. */ |
901 | if (!b_empty) | |
902 | { | |
9845d120 | 903 | update_bb_for_insn_chain (a_end, b_debug_end, a); |
5cc577b6 | 904 | |
8ddad41d | 905 | BB_END (a) = b_debug_end; |
906 | BB_HEAD (b) = NULL_RTX; | |
9845d120 | 907 | } |
908 | else if (b_end != b_debug_end) | |
909 | { | |
910 | /* Move any deleted labels and other notes between the end of A | |
911 | and the debug insns that make up B after the debug insns, | |
912 | bringing the debug insns into A while keeping the notes after | |
913 | the end of A. */ | |
914 | if (NEXT_INSN (a_end) != b_debug_start) | |
915 | reorder_insns_nobb (NEXT_INSN (a_end), PREV_INSN (b_debug_start), | |
916 | b_debug_end); | |
917 | update_bb_for_insn_chain (b_debug_start, b_debug_end, a); | |
8ddad41d | 918 | BB_END (a) = b_debug_end; |
b36d64df | 919 | } |
5cc577b6 | 920 | |
3072d30e | 921 | df_bb_delete (b->index); |
18b762f0 | 922 | |
923 | /* If B was a forwarder block, propagate the locus on the edge. */ | |
81ad108c | 924 | if (forwarder_p |
925 | && LOCATION_LOCUS (EDGE_SUCC (b, 0)->goto_locus) == UNKNOWN_LOCATION) | |
18b762f0 | 926 | EDGE_SUCC (b, 0)->goto_locus = EDGE_SUCC (a, 0)->goto_locus; |
927 | ||
928 | if (dump_file) | |
929 | fprintf (dump_file, "Merged blocks %d and %d.\n", a->index, b->index); | |
b36d64df | 930 | } |
c60fa3a7 | 931 | |
3072d30e | 932 | |
c60fa3a7 | 933 | /* Return true when block A and B can be merged. */ |
5493cb9a | 934 | |
47aaf6e6 | 935 | static bool |
936 | rtl_can_merge_blocks (basic_block a, basic_block b) | |
c60fa3a7 | 937 | { |
4f18499c | 938 | /* If we are partitioning hot/cold basic blocks, we don't want to |
939 | mess up unconditional or indirect jumps that cross between hot | |
7562ed74 | 940 | and cold sections. |
941 | ||
1118aef7 | 942 | Basic block partitioning may result in some jumps that appear to |
a0c938f0 | 943 | be optimizable (or blocks that appear to be mergeable), but which really |
944 | must be left untouched (they are required to make it safely across | |
945 | partition boundaries). See the comments at the top of | |
1118aef7 | 946 | bb-reorder.c:partition_hot_cold_basic_blocks for complete details. */ |
7562ed74 | 947 | |
1897b881 | 948 | if (BB_PARTITION (a) != BB_PARTITION (b)) |
7562ed74 | 949 | return false; |
4f18499c | 950 | |
79f958cb | 951 | /* Protect the loop latches. */ |
952 | if (current_loops && b->loop_father->latch == b) | |
953 | return false; | |
954 | ||
c60fa3a7 | 955 | /* There must be exactly one edge in between the blocks. */ |
ea091dfd | 956 | return (single_succ_p (a) |
957 | && single_succ (a) == b | |
958 | && single_pred_p (b) | |
cd665a06 | 959 | && a != b |
c60fa3a7 | 960 | /* Must be simple edge. */ |
ea091dfd | 961 | && !(single_succ_edge (a)->flags & EDGE_COMPLEX) |
c60fa3a7 | 962 | && a->next_bb == b |
34154e27 | 963 | && a != ENTRY_BLOCK_PTR_FOR_FN (cfun) |
964 | && b != EXIT_BLOCK_PTR_FOR_FN (cfun) | |
c60fa3a7 | 965 | /* If the jump insn has side effects, |
966 | we can't kill the edge. */ | |
6d7dc5b9 | 967 | && (!JUMP_P (BB_END (a)) |
18f811c9 | 968 | || (reload_completed |
5496dbfc | 969 | ? simplejump_p (BB_END (a)) : onlyjump_p (BB_END (a))))); |
c60fa3a7 | 970 | } |
b36d64df | 971 | \f |
5cc577b6 | 972 | /* Return the label in the head of basic block BLOCK. Create one if it doesn't |
973 | exist. */ | |
b36d64df | 974 | |
975 | rtx | |
4c9e08a4 | 976 | block_label (basic_block block) |
b36d64df | 977 | { |
34154e27 | 978 | if (block == EXIT_BLOCK_PTR_FOR_FN (cfun)) |
b36d64df | 979 | return NULL_RTX; |
5cc577b6 | 980 | |
6d7dc5b9 | 981 | if (!LABEL_P (BB_HEAD (block))) |
b36d64df | 982 | { |
5496dbfc | 983 | BB_HEAD (block) = emit_label_before (gen_label_rtx (), BB_HEAD (block)); |
b36d64df | 984 | } |
5cc577b6 | 985 | |
5496dbfc | 986 | return BB_HEAD (block); |
b36d64df | 987 | } |
988 | ||
989 | /* Attempt to perform edge redirection by replacing possibly complex jump | |
5cc577b6 | 990 | instruction by unconditional jump or removing jump completely. This can |
991 | apply only if all edges now point to the same block. The parameters and | |
992 | return values are equivalent to redirect_edge_and_branch. */ | |
b36d64df | 993 | |
4ee9c684 | 994 | edge |
c60fa3a7 | 995 | try_redirect_by_replacing_jump (edge e, basic_block target, bool in_cfglayout) |
b36d64df | 996 | { |
997 | basic_block src = e->src; | |
5496dbfc | 998 | rtx insn = BB_END (src), kill_from; |
b19beda9 | 999 | rtx set; |
b36d64df | 1000 | int fallthru = 0; |
4f18499c | 1001 | |
1002 | /* If we are partitioning hot/cold basic blocks, we don't want to | |
1003 | mess up unconditional or indirect jumps that cross between hot | |
1118aef7 | 1004 | and cold sections. |
1005 | ||
1006 | Basic block partitioning may result in some jumps that appear to | |
a0c938f0 | 1007 | be optimizable (or blocks that appear to be mergeable), but which really |
1008 | must be left untouched (they are required to make it safely across | |
1009 | partition boundaries). See the comments at the top of | |
1118aef7 | 1010 | bb-reorder.c:partition_hot_cold_basic_blocks for complete details. */ |
a0c938f0 | 1011 | |
aa78dca5 | 1012 | if (BB_PARTITION (src) != BB_PARTITION (target)) |
53f8294f | 1013 | return NULL; |
4f18499c | 1014 | |
34f05bfa | 1015 | /* We can replace or remove a complex jump only when we have exactly |
1016 | two edges. Also, if we have exactly one outgoing edge, we can | |
1017 | redirect that. */ | |
1018 | if (EDGE_COUNT (src->succs) >= 3 | |
1019 | /* Verify that all targets will be TARGET. Specifically, the | |
1020 | edge that is not E must also go to TARGET. */ | |
1021 | || (EDGE_COUNT (src->succs) == 2 | |
1022 | && EDGE_SUCC (src, EDGE_SUCC (src, 0) == e)->dest != target)) | |
1023 | return NULL; | |
5cc577b6 | 1024 | |
34f05bfa | 1025 | if (!onlyjump_p (insn)) |
4ee9c684 | 1026 | return NULL; |
e5562ab8 | 1027 | if ((!optimize || reload_completed) && tablejump_p (insn, NULL, NULL)) |
4ee9c684 | 1028 | return NULL; |
b36d64df | 1029 | |
1030 | /* Avoid removing branch with side effects. */ | |
1031 | set = single_set (insn); | |
1032 | if (!set || side_effects_p (set)) | |
4ee9c684 | 1033 | return NULL; |
b36d64df | 1034 | |
1035 | /* In case we zap a conditional jump, we'll need to kill | |
1036 | the cc0 setter too. */ | |
1037 | kill_from = insn; | |
1038 | #ifdef HAVE_cc0 | |
3d5a3e76 | 1039 | if (reg_mentioned_p (cc0_rtx, PATTERN (insn)) |
1040 | && only_sets_cc0_p (PREV_INSN (insn))) | |
b36d64df | 1041 | kill_from = PREV_INSN (insn); |
1042 | #endif | |
1043 | ||
1044 | /* See if we can create the fallthru edge. */ | |
c60fa3a7 | 1045 | if (in_cfglayout || can_fallthru (src, target)) |
b36d64df | 1046 | { |
450d042a | 1047 | if (dump_file) |
1048 | fprintf (dump_file, "Removing jump %i.\n", INSN_UID (insn)); | |
b36d64df | 1049 | fallthru = 1; |
1050 | ||
4a82352a | 1051 | /* Selectively unlink whole insn chain. */ |
c60fa3a7 | 1052 | if (in_cfglayout) |
1053 | { | |
43e94e51 | 1054 | rtx insn = BB_FOOTER (src); |
c60fa3a7 | 1055 | |
39257eb5 | 1056 | delete_insn_chain (kill_from, BB_END (src), false); |
c60fa3a7 | 1057 | |
1058 | /* Remove barriers but keep jumptables. */ | |
1059 | while (insn) | |
1060 | { | |
6d7dc5b9 | 1061 | if (BARRIER_P (insn)) |
c60fa3a7 | 1062 | { |
1063 | if (PREV_INSN (insn)) | |
1064 | NEXT_INSN (PREV_INSN (insn)) = NEXT_INSN (insn); | |
1065 | else | |
43e94e51 | 1066 | BB_FOOTER (src) = NEXT_INSN (insn); |
c60fa3a7 | 1067 | if (NEXT_INSN (insn)) |
1068 | PREV_INSN (NEXT_INSN (insn)) = PREV_INSN (insn); | |
1069 | } | |
6d7dc5b9 | 1070 | if (LABEL_P (insn)) |
c60fa3a7 | 1071 | break; |
1072 | insn = NEXT_INSN (insn); | |
1073 | } | |
1074 | } | |
1075 | else | |
39257eb5 | 1076 | delete_insn_chain (kill_from, PREV_INSN (BB_HEAD (target)), |
1077 | false); | |
b36d64df | 1078 | } |
5cc577b6 | 1079 | |
b36d64df | 1080 | /* If this already is simplejump, redirect it. */ |
1081 | else if (simplejump_p (insn)) | |
1082 | { | |
1083 | if (e->dest == target) | |
4ee9c684 | 1084 | return NULL; |
450d042a | 1085 | if (dump_file) |
1086 | fprintf (dump_file, "Redirecting jump %i from %i to %i.\n", | |
b3d6de89 | 1087 | INSN_UID (insn), e->dest->index, target->index); |
8963581a | 1088 | if (!redirect_jump (insn, block_label (target), 0)) |
1089 | { | |
34154e27 | 1090 | gcc_assert (target == EXIT_BLOCK_PTR_FOR_FN (cfun)); |
cc636d56 | 1091 | return NULL; |
8963581a | 1092 | } |
b36d64df | 1093 | } |
5cc577b6 | 1094 | |
8963581a | 1095 | /* Cannot do anything for target exit block. */ |
34154e27 | 1096 | else if (target == EXIT_BLOCK_PTR_FOR_FN (cfun)) |
4ee9c684 | 1097 | return NULL; |
8963581a | 1098 | |
b36d64df | 1099 | /* Or replace possibly complicated jump insn by simple jump insn. */ |
1100 | else | |
1101 | { | |
1102 | rtx target_label = block_label (target); | |
669f9131 | 1103 | rtx barrier, label, table; |
b36d64df | 1104 | |
0891f67c | 1105 | emit_jump_insn_after_noloc (gen_jump (target_label), insn); |
5496dbfc | 1106 | JUMP_LABEL (BB_END (src)) = target_label; |
b36d64df | 1107 | LABEL_NUSES (target_label)++; |
450d042a | 1108 | if (dump_file) |
1109 | fprintf (dump_file, "Replacing insn %i by jump %i\n", | |
5496dbfc | 1110 | INSN_UID (insn), INSN_UID (BB_END (src))); |
b36d64df | 1111 | |
1ed8ccdb | 1112 | |
201f6961 | 1113 | delete_insn_chain (kill_from, insn, false); |
1114 | ||
1ed8ccdb | 1115 | /* Recognize a tablejump that we are converting to a |
1116 | simple jump and remove its associated CODE_LABEL | |
1117 | and ADDR_VEC or ADDR_DIFF_VEC. */ | |
201f6961 | 1118 | if (tablejump_p (insn, &label, &table)) |
1119 | delete_insn_chain (label, table, false); | |
669f9131 | 1120 | |
5496dbfc | 1121 | barrier = next_nonnote_insn (BB_END (src)); |
6d7dc5b9 | 1122 | if (!barrier || !BARRIER_P (barrier)) |
5496dbfc | 1123 | emit_barrier_after (BB_END (src)); |
1824678b | 1124 | else |
1125 | { | |
5496dbfc | 1126 | if (barrier != NEXT_INSN (BB_END (src))) |
1824678b | 1127 | { |
1128 | /* Move the jump before barrier so that the notes | |
1129 | which originally were or were created before jump table are | |
1130 | inside the basic block. */ | |
5496dbfc | 1131 | rtx new_insn = BB_END (src); |
1824678b | 1132 | |
f41d4683 | 1133 | update_bb_for_insn_chain (NEXT_INSN (BB_END (src)), |
1134 | PREV_INSN (barrier), src); | |
1824678b | 1135 | |
1136 | NEXT_INSN (PREV_INSN (new_insn)) = NEXT_INSN (new_insn); | |
1137 | PREV_INSN (NEXT_INSN (new_insn)) = PREV_INSN (new_insn); | |
1138 | ||
1139 | NEXT_INSN (new_insn) = barrier; | |
1140 | NEXT_INSN (PREV_INSN (barrier)) = new_insn; | |
1141 | ||
1142 | PREV_INSN (new_insn) = PREV_INSN (barrier); | |
1143 | PREV_INSN (barrier) = new_insn; | |
1144 | } | |
1145 | } | |
b36d64df | 1146 | } |
1147 | ||
1148 | /* Keep only one edge out and set proper flags. */ | |
ea091dfd | 1149 | if (!single_succ_p (src)) |
cd665a06 | 1150 | remove_edge (e); |
ea091dfd | 1151 | gcc_assert (single_succ_p (src)); |
cd665a06 | 1152 | |
ea091dfd | 1153 | e = single_succ_edge (src); |
b36d64df | 1154 | if (fallthru) |
1155 | e->flags = EDGE_FALLTHRU; | |
1156 | else | |
1157 | e->flags = 0; | |
5cc577b6 | 1158 | |
b36d64df | 1159 | e->probability = REG_BR_PROB_BASE; |
1160 | e->count = src->count; | |
1161 | ||
b36d64df | 1162 | if (e->dest != target) |
1163 | redirect_edge_succ (e, target); | |
4ee9c684 | 1164 | return e; |
b36d64df | 1165 | } |
1166 | ||
a8dd994c | 1167 | /* Subroutine of redirect_branch_edge that tries to patch the jump |
1168 | instruction INSN so that it reaches block NEW. Do this | |
1169 | only when it originally reached block OLD. Return true if this | |
1170 | worked or the original target wasn't OLD, return false if redirection | |
1171 | doesn't work. */ | |
1172 | ||
1173 | static bool | |
1174 | patch_jump_insn (rtx insn, rtx old_label, basic_block new_bb) | |
b36d64df | 1175 | { |
1176 | rtx tmp; | |
b36d64df | 1177 | /* Recognize a tablejump and adjust all matching cases. */ |
b19beda9 | 1178 | if (tablejump_p (insn, NULL, &tmp)) |
b36d64df | 1179 | { |
1180 | rtvec vec; | |
1181 | int j; | |
a8dd994c | 1182 | rtx new_label = block_label (new_bb); |
b36d64df | 1183 | |
34154e27 | 1184 | if (new_bb == EXIT_BLOCK_PTR_FOR_FN (cfun)) |
a8dd994c | 1185 | return false; |
b36d64df | 1186 | if (GET_CODE (PATTERN (tmp)) == ADDR_VEC) |
1187 | vec = XVEC (PATTERN (tmp), 0); | |
1188 | else | |
1189 | vec = XVEC (PATTERN (tmp), 1); | |
1190 | ||
1191 | for (j = GET_NUM_ELEM (vec) - 1; j >= 0; --j) | |
1192 | if (XEXP (RTVEC_ELT (vec, j), 0) == old_label) | |
1193 | { | |
1194 | RTVEC_ELT (vec, j) = gen_rtx_LABEL_REF (Pmode, new_label); | |
1195 | --LABEL_NUSES (old_label); | |
1196 | ++LABEL_NUSES (new_label); | |
1197 | } | |
1198 | ||
2358393e | 1199 | /* Handle casesi dispatch insns. */ |
b36d64df | 1200 | if ((tmp = single_set (insn)) != NULL |
1201 | && SET_DEST (tmp) == pc_rtx | |
1202 | && GET_CODE (SET_SRC (tmp)) == IF_THEN_ELSE | |
1203 | && GET_CODE (XEXP (SET_SRC (tmp), 2)) == LABEL_REF | |
1204 | && XEXP (XEXP (SET_SRC (tmp), 2), 0) == old_label) | |
1205 | { | |
514b43f8 | 1206 | XEXP (SET_SRC (tmp), 2) = gen_rtx_LABEL_REF (Pmode, |
b36d64df | 1207 | new_label); |
1208 | --LABEL_NUSES (old_label); | |
1209 | ++LABEL_NUSES (new_label); | |
1210 | } | |
1211 | } | |
78f55ca8 | 1212 | else if ((tmp = extract_asm_operands (PATTERN (insn))) != NULL) |
1213 | { | |
1214 | int i, n = ASM_OPERANDS_LABEL_LENGTH (tmp); | |
1215 | rtx new_label, note; | |
1216 | ||
34154e27 | 1217 | if (new_bb == EXIT_BLOCK_PTR_FOR_FN (cfun)) |
78f55ca8 | 1218 | return false; |
1219 | new_label = block_label (new_bb); | |
1220 | ||
1221 | for (i = 0; i < n; ++i) | |
1222 | { | |
1223 | rtx old_ref = ASM_OPERANDS_LABEL (tmp, i); | |
1224 | gcc_assert (GET_CODE (old_ref) == LABEL_REF); | |
1225 | if (XEXP (old_ref, 0) == old_label) | |
1226 | { | |
1227 | ASM_OPERANDS_LABEL (tmp, i) | |
1228 | = gen_rtx_LABEL_REF (Pmode, new_label); | |
1229 | --LABEL_NUSES (old_label); | |
1230 | ++LABEL_NUSES (new_label); | |
1231 | } | |
1232 | } | |
1233 | ||
1234 | if (JUMP_LABEL (insn) == old_label) | |
1235 | { | |
1236 | JUMP_LABEL (insn) = new_label; | |
1237 | note = find_reg_note (insn, REG_LABEL_TARGET, new_label); | |
1238 | if (note) | |
1239 | remove_note (insn, note); | |
1240 | } | |
1241 | else | |
1242 | { | |
1243 | note = find_reg_note (insn, REG_LABEL_TARGET, old_label); | |
1244 | if (note) | |
1245 | remove_note (insn, note); | |
1246 | if (JUMP_LABEL (insn) != new_label | |
1247 | && !find_reg_note (insn, REG_LABEL_TARGET, new_label)) | |
1248 | add_reg_note (insn, REG_LABEL_TARGET, new_label); | |
1249 | } | |
dcb172b4 | 1250 | while ((note = find_reg_note (insn, REG_LABEL_OPERAND, old_label)) |
1251 | != NULL_RTX) | |
1252 | XEXP (note, 0) = new_label; | |
78f55ca8 | 1253 | } |
b36d64df | 1254 | else |
1255 | { | |
1256 | /* ?? We may play the games with moving the named labels from | |
1257 | one basic block to the other in case only one computed_jump is | |
1258 | available. */ | |
5cc577b6 | 1259 | if (computed_jump_p (insn) |
1260 | /* A return instruction can't be redirected. */ | |
1261 | || returnjump_p (insn)) | |
a8dd994c | 1262 | return false; |
8963581a | 1263 | |
a8dd994c | 1264 | if (!currently_expanding_to_rtl || JUMP_LABEL (insn) == old_label) |
8963581a | 1265 | { |
a8dd994c | 1266 | /* If the insn doesn't go where we think, we're confused. */ |
1267 | gcc_assert (JUMP_LABEL (insn) == old_label); | |
1268 | ||
1269 | /* If the substitution doesn't succeed, die. This can happen | |
1270 | if the back end emitted unrecognizable instructions or if | |
1271 | target is exit block on some arches. */ | |
1272 | if (!redirect_jump (insn, block_label (new_bb), 0)) | |
1273 | { | |
34154e27 | 1274 | gcc_assert (new_bb == EXIT_BLOCK_PTR_FOR_FN (cfun)); |
a8dd994c | 1275 | return false; |
1276 | } | |
8963581a | 1277 | } |
b36d64df | 1278 | } |
a8dd994c | 1279 | return true; |
1280 | } | |
1281 | ||
1282 | ||
1283 | /* Redirect edge representing branch of (un)conditional jump or tablejump, | |
1284 | NULL on failure */ | |
1285 | static edge | |
1286 | redirect_branch_edge (edge e, basic_block target) | |
1287 | { | |
1288 | rtx old_label = BB_HEAD (e->dest); | |
1289 | basic_block src = e->src; | |
1290 | rtx insn = BB_END (src); | |
1291 | ||
1292 | /* We can only redirect non-fallthru edges of jump insn. */ | |
1293 | if (e->flags & EDGE_FALLTHRU) | |
1294 | return NULL; | |
1295 | else if (!JUMP_P (insn) && !currently_expanding_to_rtl) | |
1296 | return NULL; | |
1297 | ||
1298 | if (!currently_expanding_to_rtl) | |
1299 | { | |
1300 | if (!patch_jump_insn (insn, old_label, target)) | |
1301 | return NULL; | |
1302 | } | |
1303 | else | |
1304 | /* When expanding this BB might actually contain multiple | |
1305 | jumps (i.e. not yet split by find_many_sub_basic_blocks). | |
1306 | Redirect all of those that match our label. */ | |
50b15e04 | 1307 | FOR_BB_INSNS (src, insn) |
a8dd994c | 1308 | if (JUMP_P (insn) && !patch_jump_insn (insn, old_label, target)) |
1309 | return NULL; | |
b36d64df | 1310 | |
450d042a | 1311 | if (dump_file) |
1312 | fprintf (dump_file, "Edge %i->%i redirected to %i\n", | |
b3d6de89 | 1313 | e->src->index, e->dest->index, target->index); |
5cc577b6 | 1314 | |
b36d64df | 1315 | if (e->dest != target) |
4ee9c684 | 1316 | e = redirect_edge_succ_nodup (e, target); |
3072d30e | 1317 | |
4ee9c684 | 1318 | return e; |
c60fa3a7 | 1319 | } |
1320 | ||
aa78dca5 | 1321 | /* Called when edge E has been redirected to a new destination, |
1322 | in order to update the region crossing flag on the edge and | |
1323 | jump. */ | |
1324 | ||
1325 | static void | |
1326 | fixup_partition_crossing (edge e) | |
1327 | { | |
1328 | rtx note; | |
1329 | ||
34154e27 | 1330 | if (e->src == ENTRY_BLOCK_PTR_FOR_FN (cfun) || e->dest |
1331 | == EXIT_BLOCK_PTR_FOR_FN (cfun)) | |
aa78dca5 | 1332 | return; |
1333 | /* If we redirected an existing edge, it may already be marked | |
1334 | crossing, even though the new src is missing a reg crossing note. | |
1335 | But make sure reg crossing note doesn't already exist before | |
1336 | inserting. */ | |
1337 | if (BB_PARTITION (e->src) != BB_PARTITION (e->dest)) | |
1338 | { | |
1339 | e->flags |= EDGE_CROSSING; | |
1340 | note = find_reg_note (BB_END (e->src), REG_CROSSING_JUMP, NULL_RTX); | |
1341 | if (JUMP_P (BB_END (e->src)) | |
1342 | && !note) | |
1343 | add_reg_note (BB_END (e->src), REG_CROSSING_JUMP, NULL_RTX); | |
1344 | } | |
1345 | else if (BB_PARTITION (e->src) == BB_PARTITION (e->dest)) | |
1346 | { | |
1347 | e->flags &= ~EDGE_CROSSING; | |
1348 | /* Remove the section crossing note from jump at end of | |
1349 | src if it exists, and if no other successors are | |
1350 | still crossing. */ | |
1351 | note = find_reg_note (BB_END (e->src), REG_CROSSING_JUMP, NULL_RTX); | |
1352 | if (note) | |
1353 | { | |
1354 | bool has_crossing_succ = false; | |
1355 | edge e2; | |
1356 | edge_iterator ei; | |
1357 | FOR_EACH_EDGE (e2, ei, e->src->succs) | |
1358 | { | |
1359 | has_crossing_succ |= (e2->flags & EDGE_CROSSING); | |
1360 | if (has_crossing_succ) | |
1361 | break; | |
1362 | } | |
1363 | if (!has_crossing_succ) | |
1364 | remove_note (BB_END (e->src), note); | |
1365 | } | |
1366 | } | |
1367 | } | |
1368 | ||
80adc5a6 | 1369 | /* Called when block BB has been reassigned to the cold partition, |
1370 | because it is now dominated by another cold block, | |
1371 | to ensure that the region crossing attributes are updated. */ | |
1372 | ||
1373 | static void | |
1374 | fixup_new_cold_bb (basic_block bb) | |
1375 | { | |
1376 | edge e; | |
1377 | edge_iterator ei; | |
1378 | ||
1379 | /* This is called when a hot bb is found to now be dominated | |
1380 | by a cold bb and therefore needs to become cold. Therefore, | |
1381 | its preds will no longer be region crossing. Any non-dominating | |
1382 | preds that were previously hot would also have become cold | |
1383 | in the caller for the same region. Any preds that were previously | |
1384 | region-crossing will be adjusted in fixup_partition_crossing. */ | |
1385 | FOR_EACH_EDGE (e, ei, bb->preds) | |
1386 | { | |
1387 | fixup_partition_crossing (e); | |
1388 | } | |
1389 | ||
1390 | /* Possibly need to make bb's successor edges region crossing, | |
1391 | or remove stale region crossing. */ | |
1392 | FOR_EACH_EDGE (e, ei, bb->succs) | |
1393 | { | |
1394 | /* We can't have fall-through edges across partition boundaries. | |
1395 | Note that force_nonfallthru will do any necessary partition | |
1396 | boundary fixup by calling fixup_partition_crossing itself. */ | |
1397 | if ((e->flags & EDGE_FALLTHRU) | |
1398 | && BB_PARTITION (bb) != BB_PARTITION (e->dest) | |
34154e27 | 1399 | && e->dest != EXIT_BLOCK_PTR_FOR_FN (cfun)) |
80adc5a6 | 1400 | force_nonfallthru (e); |
1401 | else | |
1402 | fixup_partition_crossing (e); | |
1403 | } | |
1404 | } | |
1405 | ||
c60fa3a7 | 1406 | /* Attempt to change code to redirect edge E to TARGET. Don't do that on |
1407 | expense of adding new instructions or reordering basic blocks. | |
1408 | ||
1409 | Function can be also called with edge destination equivalent to the TARGET. | |
1410 | Then it should try the simplifications and do nothing if none is possible. | |
1411 | ||
4ee9c684 | 1412 | Return edge representing the branch if transformation succeeded. Return NULL |
1413 | on failure. | |
1414 | We still return NULL in case E already destinated TARGET and we didn't | |
1415 | managed to simplify instruction stream. */ | |
c60fa3a7 | 1416 | |
4ee9c684 | 1417 | static edge |
f82b06e0 | 1418 | rtl_redirect_edge_and_branch (edge e, basic_block target) |
c60fa3a7 | 1419 | { |
4ee9c684 | 1420 | edge ret; |
adee86a0 | 1421 | basic_block src = e->src; |
aa78dca5 | 1422 | basic_block dest = e->dest; |
adee86a0 | 1423 | |
c60fa3a7 | 1424 | if (e->flags & (EDGE_ABNORMAL_CALL | EDGE_EH)) |
4ee9c684 | 1425 | return NULL; |
c60fa3a7 | 1426 | |
aa78dca5 | 1427 | if (dest == target) |
4ee9c684 | 1428 | return e; |
e5562ab8 | 1429 | |
4ee9c684 | 1430 | if ((ret = try_redirect_by_replacing_jump (e, target, false)) != NULL) |
adee86a0 | 1431 | { |
3072d30e | 1432 | df_set_bb_dirty (src); |
aa78dca5 | 1433 | fixup_partition_crossing (ret); |
4ee9c684 | 1434 | return ret; |
adee86a0 | 1435 | } |
c60fa3a7 | 1436 | |
4ee9c684 | 1437 | ret = redirect_branch_edge (e, target); |
1438 | if (!ret) | |
1439 | return NULL; | |
5cc577b6 | 1440 | |
3072d30e | 1441 | df_set_bb_dirty (src); |
aa78dca5 | 1442 | fixup_partition_crossing (ret); |
4ee9c684 | 1443 | return ret; |
b36d64df | 1444 | } |
1445 | ||
aa78dca5 | 1446 | /* Emit a barrier after BB, into the footer if we are in CFGLAYOUT mode. */ |
1447 | ||
1448 | void | |
1449 | emit_barrier_after_bb (basic_block bb) | |
1450 | { | |
1451 | rtx barrier = emit_barrier_after (BB_END (bb)); | |
9af5ce0c | 1452 | gcc_assert (current_ir_type () == IR_RTL_CFGRTL |
aa78dca5 | 1453 | || current_ir_type () == IR_RTL_CFGLAYOUT); |
1454 | if (current_ir_type () == IR_RTL_CFGLAYOUT) | |
1455 | BB_FOOTER (bb) = unlink_insn_chain (barrier, barrier); | |
1456 | } | |
1457 | ||
20dd417a | 1458 | /* Like force_nonfallthru below, but additionally performs redirection |
9cb2517e | 1459 | Used by redirect_edge_and_branch_force. JUMP_LABEL is used only |
1460 | when redirecting to the EXIT_BLOCK, it is either ret_rtx or | |
1461 | simple_return_rtx, indicating which kind of returnjump to create. | |
1462 | It should be NULL otherwise. */ | |
b36d64df | 1463 | |
4115ac36 | 1464 | basic_block |
9cb2517e | 1465 | force_nonfallthru_and_redirect (edge e, basic_block target, rtx jump_label) |
b36d64df | 1466 | { |
498d173d | 1467 | basic_block jump_block, new_bb = NULL, src = e->src; |
b36d64df | 1468 | rtx note; |
1469 | edge new_edge; | |
498d173d | 1470 | int abnormal_edge_flags = 0; |
d7ff3ab6 | 1471 | bool asm_goto_edge = false; |
9c388755 | 1472 | int loc; |
b36d64df | 1473 | |
accd6c44 | 1474 | /* In the case the last instruction is conditional jump to the next |
1475 | instruction, first redirect the jump itself and then continue | |
df07c3ae | 1476 | by creating a basic block afterwards to redirect fallthru edge. */ |
34154e27 | 1477 | if (e->src != ENTRY_BLOCK_PTR_FOR_FN (cfun) |
1478 | && e->dest != EXIT_BLOCK_PTR_FOR_FN (cfun) | |
5496dbfc | 1479 | && any_condjump_p (BB_END (e->src)) |
5496dbfc | 1480 | && JUMP_LABEL (BB_END (e->src)) == BB_HEAD (e->dest)) |
accd6c44 | 1481 | { |
1482 | rtx note; | |
d9aa52be | 1483 | edge b = unchecked_make_edge (e->src, target, 0); |
cc636d56 | 1484 | bool redirected; |
accd6c44 | 1485 | |
cc636d56 | 1486 | redirected = redirect_jump (BB_END (e->src), block_label (target), 0); |
1487 | gcc_assert (redirected); | |
a0c938f0 | 1488 | |
5496dbfc | 1489 | note = find_reg_note (BB_END (e->src), REG_BR_PROB, NULL_RTX); |
accd6c44 | 1490 | if (note) |
1491 | { | |
9eb946de | 1492 | int prob = XINT (note, 0); |
accd6c44 | 1493 | |
1494 | b->probability = prob; | |
f9d4b7f4 | 1495 | /* Update this to use GCOV_COMPUTE_SCALE. */ |
accd6c44 | 1496 | b->count = e->count * prob / REG_BR_PROB_BASE; |
1497 | e->probability -= e->probability; | |
1498 | e->count -= b->count; | |
1499 | if (e->probability < 0) | |
1500 | e->probability = 0; | |
1501 | if (e->count < 0) | |
1502 | e->count = 0; | |
1503 | } | |
1504 | } | |
1505 | ||
b36d64df | 1506 | if (e->flags & EDGE_ABNORMAL) |
498d173d | 1507 | { |
1508 | /* Irritating special case - fallthru edge to the same block as abnormal | |
1509 | edge. | |
1510 | We can't redirect abnormal edge, but we still can split the fallthru | |
4c9e08a4 | 1511 | one and create separate abnormal edge to original destination. |
498d173d | 1512 | This allows bb-reorder to make such edge non-fallthru. */ |
cc636d56 | 1513 | gcc_assert (e->dest == target); |
4ecbba1a | 1514 | abnormal_edge_flags = e->flags & ~EDGE_FALLTHRU; |
1515 | e->flags &= EDGE_FALLTHRU; | |
498d173d | 1516 | } |
cc636d56 | 1517 | else |
76cc9616 | 1518 | { |
cc636d56 | 1519 | gcc_assert (e->flags & EDGE_FALLTHRU); |
34154e27 | 1520 | if (e->src == ENTRY_BLOCK_PTR_FOR_FN (cfun)) |
cc636d56 | 1521 | { |
1522 | /* We can't redirect the entry block. Create an empty block | |
cd665a06 | 1523 | at the start of the function which we use to add the new |
1524 | jump. */ | |
1525 | edge tmp; | |
1526 | edge_iterator ei; | |
1527 | bool found = false; | |
a0c938f0 | 1528 | |
34154e27 | 1529 | basic_block bb = create_basic_block (BB_HEAD (e->dest), NULL, |
1530 | ENTRY_BLOCK_PTR_FOR_FN (cfun)); | |
a0c938f0 | 1531 | |
cc636d56 | 1532 | /* Change the existing edge's source to be the new block, and add |
1533 | a new edge from the entry block to the new block. */ | |
1534 | e->src = bb; | |
34154e27 | 1535 | for (ei = ei_start (ENTRY_BLOCK_PTR_FOR_FN (cfun)->succs); |
1536 | (tmp = ei_safe_edge (ei)); ) | |
cd665a06 | 1537 | { |
1538 | if (tmp == e) | |
1539 | { | |
34154e27 | 1540 | ENTRY_BLOCK_PTR_FOR_FN (cfun)->succs->unordered_remove (ei.index); |
cd665a06 | 1541 | found = true; |
1542 | break; | |
1543 | } | |
1544 | else | |
1545 | ei_next (&ei); | |
1546 | } | |
a0c938f0 | 1547 | |
cd665a06 | 1548 | gcc_assert (found); |
a0c938f0 | 1549 | |
f1f41a6c | 1550 | vec_safe_push (bb->succs, e); |
34154e27 | 1551 | make_single_succ_edge (ENTRY_BLOCK_PTR_FOR_FN (cfun), bb, |
1552 | EDGE_FALLTHRU); | |
cc636d56 | 1553 | } |
76cc9616 | 1554 | } |
1555 | ||
d7ff3ab6 | 1556 | /* If e->src ends with asm goto, see if any of the ASM_OPERANDS_LABELs |
92f67f6e | 1557 | don't point to the target or fallthru label. */ |
d7ff3ab6 | 1558 | if (JUMP_P (BB_END (e->src)) |
34154e27 | 1559 | && target != EXIT_BLOCK_PTR_FOR_FN (cfun) |
d7ff3ab6 | 1560 | && (e->flags & EDGE_FALLTHRU) |
1561 | && (note = extract_asm_operands (PATTERN (BB_END (e->src))))) | |
b36d64df | 1562 | { |
d7ff3ab6 | 1563 | int i, n = ASM_OPERANDS_LABEL_LENGTH (note); |
ca632883 | 1564 | bool adjust_jump_target = false; |
d7ff3ab6 | 1565 | |
1566 | for (i = 0; i < n; ++i) | |
92f67f6e | 1567 | { |
1568 | if (XEXP (ASM_OPERANDS_LABEL (note, i), 0) == BB_HEAD (e->dest)) | |
ca632883 | 1569 | { |
1570 | LABEL_NUSES (XEXP (ASM_OPERANDS_LABEL (note, i), 0))--; | |
1571 | XEXP (ASM_OPERANDS_LABEL (note, i), 0) = block_label (target); | |
1572 | LABEL_NUSES (XEXP (ASM_OPERANDS_LABEL (note, i), 0))++; | |
1573 | adjust_jump_target = true; | |
1574 | } | |
92f67f6e | 1575 | if (XEXP (ASM_OPERANDS_LABEL (note, i), 0) == BB_HEAD (target)) |
d7ff3ab6 | 1576 | asm_goto_edge = true; |
92f67f6e | 1577 | } |
ca632883 | 1578 | if (adjust_jump_target) |
1579 | { | |
1580 | rtx insn = BB_END (e->src), note; | |
1581 | rtx old_label = BB_HEAD (e->dest); | |
1582 | rtx new_label = BB_HEAD (target); | |
1583 | ||
1584 | if (JUMP_LABEL (insn) == old_label) | |
1585 | { | |
1586 | JUMP_LABEL (insn) = new_label; | |
1587 | note = find_reg_note (insn, REG_LABEL_TARGET, new_label); | |
1588 | if (note) | |
1589 | remove_note (insn, note); | |
1590 | } | |
1591 | else | |
1592 | { | |
1593 | note = find_reg_note (insn, REG_LABEL_TARGET, old_label); | |
1594 | if (note) | |
1595 | remove_note (insn, note); | |
1596 | if (JUMP_LABEL (insn) != new_label | |
1597 | && !find_reg_note (insn, REG_LABEL_TARGET, new_label)) | |
1598 | add_reg_note (insn, REG_LABEL_TARGET, new_label); | |
1599 | } | |
1600 | while ((note = find_reg_note (insn, REG_LABEL_OPERAND, old_label)) | |
1601 | != NULL_RTX) | |
1602 | XEXP (note, 0) = new_label; | |
1603 | } | |
d7ff3ab6 | 1604 | } |
1605 | ||
1606 | if (EDGE_COUNT (e->src->succs) >= 2 || abnormal_edge_flags || asm_goto_edge) | |
1607 | { | |
1608 | gcov_type count = e->count; | |
1609 | int probability = e->probability; | |
b36d64df | 1610 | /* Create the new structures. */ |
3160014e | 1611 | |
7a1fee99 | 1612 | /* If the old block ended with a tablejump, skip its table |
1613 | by searching forward from there. Otherwise start searching | |
1614 | forward from the last instruction of the old block. */ | |
5496dbfc | 1615 | if (!tablejump_p (BB_END (e->src), NULL, ¬e)) |
1616 | note = BB_END (e->src); | |
3160014e | 1617 | note = NEXT_INSN (note); |
1618 | ||
3160014e | 1619 | jump_block = create_basic_block (note, NULL, e->src); |
d7ff3ab6 | 1620 | jump_block->count = count; |
b36d64df | 1621 | jump_block->frequency = EDGE_FREQUENCY (e); |
b36d64df | 1622 | |
4f18499c | 1623 | /* Make sure new block ends up in correct hot/cold section. */ |
1624 | ||
7562ed74 | 1625 | BB_COPY_PARTITION (jump_block, e->src); |
a0c938f0 | 1626 | |
b36d64df | 1627 | /* Wire edge in. */ |
1628 | new_edge = make_edge (e->src, jump_block, EDGE_FALLTHRU); | |
d7ff3ab6 | 1629 | new_edge->probability = probability; |
1630 | new_edge->count = count; | |
b36d64df | 1631 | |
1632 | /* Redirect old edge. */ | |
1633 | redirect_edge_pred (e, jump_block); | |
1634 | e->probability = REG_BR_PROB_BASE; | |
1635 | ||
aa78dca5 | 1636 | /* If e->src was previously region crossing, it no longer is |
1637 | and the reg crossing note should be removed. */ | |
1638 | fixup_partition_crossing (new_edge); | |
1639 | ||
d7ff3ab6 | 1640 | /* If asm goto has any label refs to target's label, |
1641 | add also edge from asm goto bb to target. */ | |
1642 | if (asm_goto_edge) | |
1643 | { | |
1644 | new_edge->probability /= 2; | |
1645 | new_edge->count /= 2; | |
1646 | jump_block->count /= 2; | |
1647 | jump_block->frequency /= 2; | |
1648 | new_edge = make_edge (new_edge->src, target, | |
1649 | e->flags & ~EDGE_FALLTHRU); | |
1650 | new_edge->probability = probability - probability / 2; | |
1651 | new_edge->count = count - count / 2; | |
1652 | } | |
1653 | ||
b36d64df | 1654 | new_bb = jump_block; |
1655 | } | |
1656 | else | |
1657 | jump_block = e->src; | |
5cc577b6 | 1658 | |
8e7408e3 | 1659 | loc = e->goto_locus; |
b36d64df | 1660 | e->flags &= ~EDGE_FALLTHRU; |
34154e27 | 1661 | if (target == EXIT_BLOCK_PTR_FOR_FN (cfun)) |
b36d64df | 1662 | { |
9cb2517e | 1663 | if (jump_label == ret_rtx) |
1664 | { | |
38c95e2f | 1665 | #ifdef HAVE_return |
9cb2517e | 1666 | emit_jump_insn_after_setloc (gen_return (), BB_END (jump_block), loc); |
38c95e2f | 1667 | #else |
9cb2517e | 1668 | gcc_unreachable (); |
38c95e2f | 1669 | #endif |
9cb2517e | 1670 | } |
1671 | else | |
1672 | { | |
1673 | gcc_assert (jump_label == simple_return_rtx); | |
1674 | #ifdef HAVE_simple_return | |
1675 | emit_jump_insn_after_setloc (gen_simple_return (), | |
1676 | BB_END (jump_block), loc); | |
1677 | #else | |
1678 | gcc_unreachable (); | |
1679 | #endif | |
1680 | } | |
31a53363 | 1681 | set_return_jump_label (BB_END (jump_block)); |
b36d64df | 1682 | } |
1683 | else | |
1684 | { | |
1685 | rtx label = block_label (target); | |
9c388755 | 1686 | emit_jump_insn_after_setloc (gen_jump (label), BB_END (jump_block), loc); |
5496dbfc | 1687 | JUMP_LABEL (BB_END (jump_block)) = label; |
b36d64df | 1688 | LABEL_NUSES (label)++; |
1689 | } | |
5cc577b6 | 1690 | |
aa78dca5 | 1691 | /* We might be in cfg layout mode, and if so, the following routine will |
1692 | insert the barrier correctly. */ | |
1693 | emit_barrier_after_bb (jump_block); | |
b36d64df | 1694 | redirect_edge_succ_nodup (e, target); |
1695 | ||
498d173d | 1696 | if (abnormal_edge_flags) |
1697 | make_edge (src, target, abnormal_edge_flags); | |
1698 | ||
48e1416a | 1699 | df_mark_solutions_dirty (); |
aa78dca5 | 1700 | fixup_partition_crossing (e); |
b36d64df | 1701 | return new_bb; |
1702 | } | |
1703 | ||
1704 | /* Edge E is assumed to be fallthru edge. Emit needed jump instruction | |
1705 | (and possibly create new basic block) to make edge non-fallthru. | |
1706 | Return newly created BB or NULL if none. */ | |
5cc577b6 | 1707 | |
202bbc06 | 1708 | static basic_block |
1709 | rtl_force_nonfallthru (edge e) | |
b36d64df | 1710 | { |
9cb2517e | 1711 | return force_nonfallthru_and_redirect (e, e->dest, NULL_RTX); |
b36d64df | 1712 | } |
1713 | ||
1714 | /* Redirect edge even at the expense of creating new jump insn or | |
1715 | basic block. Return new basic block if created, NULL otherwise. | |
a53ff4c1 | 1716 | Conversion must be possible. */ |
b36d64df | 1717 | |
1026363d | 1718 | static basic_block |
4c9e08a4 | 1719 | rtl_redirect_edge_and_branch_force (edge e, basic_block target) |
b36d64df | 1720 | { |
5cc577b6 | 1721 | if (redirect_edge_and_branch (e, target) |
1722 | || e->dest == target) | |
b36d64df | 1723 | return NULL; |
1724 | ||
1725 | /* In case the edge redirection failed, try to force it to be non-fallthru | |
1726 | and redirect newly created simplejump. */ | |
3072d30e | 1727 | df_set_bb_dirty (e->src); |
9cb2517e | 1728 | return force_nonfallthru_and_redirect (e, target, NULL_RTX); |
b36d64df | 1729 | } |
1730 | ||
1731 | /* The given edge should potentially be a fallthru edge. If that is in | |
1732 | fact true, delete the jump and barriers that are in the way. */ | |
1733 | ||
5f5d4cd1 | 1734 | static void |
1735 | rtl_tidy_fallthru_edge (edge e) | |
b36d64df | 1736 | { |
1737 | rtx q; | |
5f5d4cd1 | 1738 | basic_block b = e->src, c = b->next_bb; |
1739 | ||
b36d64df | 1740 | /* ??? In a late-running flow pass, other folks may have deleted basic |
1741 | blocks by nopping out blocks, leaving multiple BARRIERs between here | |
442e3cb9 | 1742 | and the target label. They ought to be chastised and fixed. |
b36d64df | 1743 | |
1744 | We can also wind up with a sequence of undeletable labels between | |
1745 | one block and the next. | |
1746 | ||
1747 | So search through a sequence of barriers, labels, and notes for | |
1748 | the head of block C and assert that we really do fall through. */ | |
1749 | ||
5496dbfc | 1750 | for (q = NEXT_INSN (BB_END (b)); q != BB_HEAD (c); q = NEXT_INSN (q)) |
ac25a327 | 1751 | if (INSN_P (q)) |
1752 | return; | |
b36d64df | 1753 | |
1754 | /* Remove what will soon cease being the jump insn from the source block. | |
1755 | If block B consisted only of this single jump, turn it into a deleted | |
1756 | note. */ | |
5496dbfc | 1757 | q = BB_END (b); |
6d7dc5b9 | 1758 | if (JUMP_P (q) |
b36d64df | 1759 | && onlyjump_p (q) |
1760 | && (any_uncondjump_p (q) | |
ea091dfd | 1761 | || single_succ_p (b))) |
b36d64df | 1762 | { |
1763 | #ifdef HAVE_cc0 | |
1764 | /* If this was a conditional jump, we need to also delete | |
1765 | the insn that set cc0. */ | |
1766 | if (any_condjump_p (q) && only_sets_cc0_p (PREV_INSN (q))) | |
1767 | q = PREV_INSN (q); | |
1768 | #endif | |
1769 | ||
1770 | q = PREV_INSN (q); | |
b36d64df | 1771 | } |
1772 | ||
1773 | /* Selectively unlink the sequence. */ | |
5496dbfc | 1774 | if (q != PREV_INSN (BB_HEAD (c))) |
39257eb5 | 1775 | delete_insn_chain (NEXT_INSN (q), PREV_INSN (BB_HEAD (c)), false); |
b36d64df | 1776 | |
1777 | e->flags |= EDGE_FALLTHRU; | |
1778 | } | |
b36d64df | 1779 | \f |
5f5d4cd1 | 1780 | /* Should move basic block BB after basic block AFTER. NIY. */ |
1781 | ||
1782 | static bool | |
1783 | rtl_move_block_after (basic_block bb ATTRIBUTE_UNUSED, | |
1784 | basic_block after ATTRIBUTE_UNUSED) | |
1785 | { | |
1786 | return false; | |
1787 | } | |
1788 | ||
aa78dca5 | 1789 | /* Locate the last bb in the same partition as START_BB. */ |
1790 | ||
1791 | static basic_block | |
1792 | last_bb_in_partition (basic_block start_bb) | |
1793 | { | |
1794 | basic_block bb; | |
34154e27 | 1795 | FOR_BB_BETWEEN (bb, start_bb, EXIT_BLOCK_PTR_FOR_FN (cfun), next_bb) |
aa78dca5 | 1796 | { |
1797 | if (BB_PARTITION (start_bb) != BB_PARTITION (bb->next_bb)) | |
1798 | return bb; | |
1799 | } | |
efee62d1 | 1800 | /* Return bb before the exit block. */ |
aa78dca5 | 1801 | return bb->prev_bb; |
1802 | } | |
1803 | ||
b36d64df | 1804 | /* Split a (typically critical) edge. Return the new block. |
a53ff4c1 | 1805 | The edge must not be abnormal. |
b36d64df | 1806 | |
1807 | ??? The code generally expects to be called on critical edges. | |
1808 | The case of a block ending in an unconditional jump to a | |
1809 | block with multiple predecessors is not handled optimally. */ | |
1810 | ||
9140e457 | 1811 | static basic_block |
4c9e08a4 | 1812 | rtl_split_edge (edge edge_in) |
b36d64df | 1813 | { |
aa78dca5 | 1814 | basic_block bb, new_bb; |
b36d64df | 1815 | rtx before; |
1816 | ||
1817 | /* Abnormal edges cannot be split. */ | |
cc636d56 | 1818 | gcc_assert (!(edge_in->flags & EDGE_ABNORMAL)); |
b36d64df | 1819 | |
1820 | /* We are going to place the new block in front of edge destination. | |
4a82352a | 1821 | Avoid existence of fallthru predecessors. */ |
b36d64df | 1822 | if ((edge_in->flags & EDGE_FALLTHRU) == 0) |
1823 | { | |
7f58c05e | 1824 | edge e = find_fallthru_edge (edge_in->dest->preds); |
b36d64df | 1825 | |
1826 | if (e) | |
1827 | force_nonfallthru (e); | |
1828 | } | |
1829 | ||
588aadb7 | 1830 | /* Create the basic block note. */ |
34154e27 | 1831 | if (edge_in->dest != EXIT_BLOCK_PTR_FOR_FN (cfun)) |
5496dbfc | 1832 | before = BB_HEAD (edge_in->dest); |
b36d64df | 1833 | else |
1834 | before = NULL_RTX; | |
1835 | ||
9bb8a4af | 1836 | /* If this is a fall through edge to the exit block, the blocks might be |
0a55d497 | 1837 | not adjacent, and the right place is after the source. */ |
34154e27 | 1838 | if ((edge_in->flags & EDGE_FALLTHRU) |
1839 | && edge_in->dest == EXIT_BLOCK_PTR_FOR_FN (cfun)) | |
9bb8a4af | 1840 | { |
1841 | before = NEXT_INSN (BB_END (edge_in->src)); | |
9bb8a4af | 1842 | bb = create_basic_block (before, NULL, edge_in->src); |
7562ed74 | 1843 | BB_COPY_PARTITION (bb, edge_in->src); |
9bb8a4af | 1844 | } |
1845 | else | |
065efcb1 | 1846 | { |
34154e27 | 1847 | if (edge_in->src == ENTRY_BLOCK_PTR_FOR_FN (cfun)) |
aa78dca5 | 1848 | { |
1849 | bb = create_basic_block (before, NULL, edge_in->dest->prev_bb); | |
1850 | BB_COPY_PARTITION (bb, edge_in->dest); | |
1851 | } | |
1852 | else | |
1853 | { | |
1854 | basic_block after = edge_in->dest->prev_bb; | |
1855 | /* If this is post-bb reordering, and the edge crosses a partition | |
1856 | boundary, the new block needs to be inserted in the bb chain | |
1857 | at the end of the src partition (since we put the new bb into | |
1858 | that partition, see below). Otherwise we may end up creating | |
1859 | an extra partition crossing in the chain, which is illegal. | |
1860 | It can't go after the src, because src may have a fall-through | |
1861 | to a different block. */ | |
1862 | if (crtl->bb_reorder_complete | |
1863 | && (edge_in->flags & EDGE_CROSSING)) | |
1864 | { | |
1865 | after = last_bb_in_partition (edge_in->src); | |
1866 | before = NEXT_INSN (BB_END (after)); | |
1867 | /* The instruction following the last bb in partition should | |
1868 | be a barrier, since it cannot end in a fall-through. */ | |
1869 | gcc_checking_assert (BARRIER_P (before)); | |
1870 | before = NEXT_INSN (before); | |
1871 | } | |
1872 | bb = create_basic_block (before, NULL, after); | |
1873 | /* Put the split bb into the src partition, to avoid creating | |
1874 | a situation where a cold bb dominates a hot bb, in the case | |
1875 | where src is cold and dest is hot. The src will dominate | |
1876 | the new bb (whereas it might not have dominated dest). */ | |
1877 | BB_COPY_PARTITION (bb, edge_in->src); | |
1878 | } | |
065efcb1 | 1879 | } |
b36d64df | 1880 | |
805e22b2 | 1881 | make_single_succ_edge (bb, edge_in->dest, EDGE_FALLTHRU); |
b36d64df | 1882 | |
aa78dca5 | 1883 | /* Can't allow a region crossing edge to be fallthrough. */ |
1884 | if (BB_PARTITION (bb) != BB_PARTITION (edge_in->dest) | |
34154e27 | 1885 | && edge_in->dest != EXIT_BLOCK_PTR_FOR_FN (cfun)) |
aa78dca5 | 1886 | { |
1887 | new_bb = force_nonfallthru (single_succ_edge (bb)); | |
1888 | gcc_assert (!new_bb); | |
1889 | } | |
1890 | ||
917bbcab | 1891 | /* For non-fallthru edges, we must adjust the predecessor's |
b36d64df | 1892 | jump instruction to target our new block. */ |
1893 | if ((edge_in->flags & EDGE_FALLTHRU) == 0) | |
1894 | { | |
cc636d56 | 1895 | edge redirected = redirect_edge_and_branch (edge_in, bb); |
1896 | gcc_assert (redirected); | |
b36d64df | 1897 | } |
1898 | else | |
dcb172b4 | 1899 | { |
34154e27 | 1900 | if (edge_in->src != ENTRY_BLOCK_PTR_FOR_FN (cfun)) |
dcb172b4 | 1901 | { |
1902 | /* For asm goto even splitting of fallthru edge might | |
1903 | need insn patching, as other labels might point to the | |
1904 | old label. */ | |
1905 | rtx last = BB_END (edge_in->src); | |
1906 | if (last | |
1907 | && JUMP_P (last) | |
34154e27 | 1908 | && edge_in->dest != EXIT_BLOCK_PTR_FOR_FN (cfun) |
dcb172b4 | 1909 | && extract_asm_operands (PATTERN (last)) != NULL_RTX |
1910 | && patch_jump_insn (last, before, bb)) | |
1911 | df_set_bb_dirty (edge_in->src); | |
1912 | } | |
1913 | redirect_edge_succ (edge_in, bb); | |
1914 | } | |
b36d64df | 1915 | |
1916 | return bb; | |
1917 | } | |
1918 | ||
1919 | /* Queue instructions for insertion on an edge between two basic blocks. | |
1920 | The new instructions and basic blocks (if any) will not appear in the | |
1921 | CFG until commit_edge_insertions is called. */ | |
1922 | ||
1923 | void | |
4c9e08a4 | 1924 | insert_insn_on_edge (rtx pattern, edge e) |
b36d64df | 1925 | { |
1926 | /* We cannot insert instructions on an abnormal critical edge. | |
1927 | It will be easier to find the culprit if we die now. */ | |
cc636d56 | 1928 | gcc_assert (!((e->flags & EDGE_ABNORMAL) && EDGE_CRITICAL_P (e))); |
b36d64df | 1929 | |
4ee9c684 | 1930 | if (e->insns.r == NULL_RTX) |
b36d64df | 1931 | start_sequence (); |
1932 | else | |
4ee9c684 | 1933 | push_to_sequence (e->insns.r); |
b36d64df | 1934 | |
1935 | emit_insn (pattern); | |
1936 | ||
4ee9c684 | 1937 | e->insns.r = get_insns (); |
b36d64df | 1938 | end_sequence (); |
1939 | } | |
1940 | ||
1941 | /* Update the CFG for the instructions queued on edge E. */ | |
1942 | ||
a8dd994c | 1943 | void |
ca462ec0 | 1944 | commit_one_edge_insertion (edge e) |
b36d64df | 1945 | { |
1946 | rtx before = NULL_RTX, after = NULL_RTX, insns, tmp, last; | |
53105d88 | 1947 | basic_block bb; |
b36d64df | 1948 | |
1949 | /* Pull the insns off the edge now since the edge might go away. */ | |
4ee9c684 | 1950 | insns = e->insns.r; |
1951 | e->insns.r = NULL_RTX; | |
b36d64df | 1952 | |
53105d88 | 1953 | /* Figure out where to put these insns. If the destination has |
1954 | one predecessor, insert there. Except for the exit block. */ | |
34154e27 | 1955 | if (single_pred_p (e->dest) && e->dest != EXIT_BLOCK_PTR_FOR_FN (cfun)) |
b36d64df | 1956 | { |
53105d88 | 1957 | bb = e->dest; |
1958 | ||
1959 | /* Get the location correct wrt a code label, and "nice" wrt | |
1960 | a basic block note, and before everything else. */ | |
1961 | tmp = BB_HEAD (bb); | |
1962 | if (LABEL_P (tmp)) | |
1963 | tmp = NEXT_INSN (tmp); | |
1964 | if (NOTE_INSN_BASIC_BLOCK_P (tmp)) | |
1965 | tmp = NEXT_INSN (tmp); | |
1966 | if (tmp == BB_HEAD (bb)) | |
1967 | before = tmp; | |
1968 | else if (tmp) | |
1969 | after = PREV_INSN (tmp); | |
1970 | else | |
1971 | after = get_last_insn (); | |
1972 | } | |
fb20d6fa | 1973 | |
53105d88 | 1974 | /* If the source has one successor and the edge is not abnormal, |
8315fc61 | 1975 | insert there. Except for the entry block. |
1976 | Don't do this if the predecessor ends in a jump other than | |
1977 | unconditional simple jump. E.g. for asm goto that points all | |
1978 | its labels at the fallthru basic block, we can't insert instructions | |
1979 | before the asm goto, as the asm goto can have various of side effects, | |
1980 | and can't emit instructions after the asm goto, as it must end | |
1981 | the basic block. */ | |
53105d88 | 1982 | else if ((e->flags & EDGE_ABNORMAL) == 0 |
1983 | && single_succ_p (e->src) | |
34154e27 | 1984 | && e->src != ENTRY_BLOCK_PTR_FOR_FN (cfun) |
8315fc61 | 1985 | && (!JUMP_P (BB_END (e->src)) |
1986 | || simplejump_p (BB_END (e->src)))) | |
53105d88 | 1987 | { |
1988 | bb = e->src; | |
fb20d6fa | 1989 | |
53105d88 | 1990 | /* It is possible to have a non-simple jump here. Consider a target |
1991 | where some forms of unconditional jumps clobber a register. This | |
1992 | happens on the fr30 for example. | |
b36d64df | 1993 | |
53105d88 | 1994 | We know this block has a single successor, so we can just emit |
1995 | the queued insns before the jump. */ | |
1996 | if (JUMP_P (BB_END (bb))) | |
1997 | before = BB_END (bb); | |
fb20d6fa | 1998 | else |
1999 | { | |
53105d88 | 2000 | /* We'd better be fallthru, or we've lost track of what's what. */ |
2001 | gcc_assert (e->flags & EDGE_FALLTHRU); | |
4f18499c | 2002 | |
53105d88 | 2003 | after = BB_END (bb); |
b36d64df | 2004 | } |
2005 | } | |
2006 | ||
53105d88 | 2007 | /* Otherwise we must split the edge. */ |
2008 | else | |
2009 | { | |
2010 | bb = split_edge (e); | |
aa78dca5 | 2011 | |
2012 | /* If E crossed a partition boundary, we needed to make bb end in | |
2013 | a region-crossing jump, even though it was originally fallthru. */ | |
2014 | if (JUMP_P (BB_END (bb))) | |
2015 | before = BB_END (bb); | |
2016 | else | |
2017 | after = BB_END (bb); | |
53105d88 | 2018 | } |
2019 | ||
2020 | /* Now that we've found the spot, do the insertion. */ | |
b36d64df | 2021 | if (before) |
2022 | { | |
3072d30e | 2023 | emit_insn_before_noloc (insns, before, bb); |
b36d64df | 2024 | last = prev_nonnote_insn (before); |
2025 | } | |
2026 | else | |
3072d30e | 2027 | last = emit_insn_after_noloc (insns, after, bb); |
b36d64df | 2028 | |
2029 | if (returnjump_p (last)) | |
2030 | { | |
2031 | /* ??? Remove all outgoing edges from BB and add one for EXIT. | |
a0c938f0 | 2032 | This is not currently a problem because this only happens |
2033 | for the (single) epilogue, which already has a fallthru edge | |
2034 | to EXIT. */ | |
b36d64df | 2035 | |
ea091dfd | 2036 | e = single_succ_edge (bb); |
34154e27 | 2037 | gcc_assert (e->dest == EXIT_BLOCK_PTR_FOR_FN (cfun) |
ea091dfd | 2038 | && single_succ_p (bb) && (e->flags & EDGE_FALLTHRU)); |
b36d64df | 2039 | |
5cc577b6 | 2040 | e->flags &= ~EDGE_FALLTHRU; |
b36d64df | 2041 | emit_barrier_after (last); |
b3d6de89 | 2042 | |
b36d64df | 2043 | if (before) |
2044 | delete_insn (before); | |
2045 | } | |
cc636d56 | 2046 | else |
2047 | gcc_assert (!JUMP_P (last)); | |
b36d64df | 2048 | } |
2049 | ||
2050 | /* Update the CFG for all queued instructions. */ | |
2051 | ||
2052 | void | |
4c9e08a4 | 2053 | commit_edge_insertions (void) |
b36d64df | 2054 | { |
b36d64df | 2055 | basic_block bb; |
2056 | ||
80adc5a6 | 2057 | /* Optimization passes that invoke this routine can cause hot blocks |
2058 | previously reached by both hot and cold blocks to become dominated only | |
2059 | by cold blocks. This will cause the verification below to fail, | |
2060 | and lead to now cold code in the hot section. In some cases this | |
2061 | may only be visible after newly unreachable blocks are deleted, | |
2062 | which will be done by fixup_partitions. */ | |
2063 | fixup_partitions (); | |
2064 | ||
b36d64df | 2065 | #ifdef ENABLE_CHECKING |
2066 | verify_flow_info (); | |
2067 | #endif | |
2068 | ||
34154e27 | 2069 | FOR_BB_BETWEEN (bb, ENTRY_BLOCK_PTR_FOR_FN (cfun), |
2070 | EXIT_BLOCK_PTR_FOR_FN (cfun), next_bb) | |
b36d64df | 2071 | { |
cd665a06 | 2072 | edge e; |
2073 | edge_iterator ei; | |
b36d64df | 2074 | |
cd665a06 | 2075 | FOR_EACH_EDGE (e, ei, bb->succs) |
2076 | if (e->insns.r) | |
202bbc06 | 2077 | commit_one_edge_insertion (e); |
fb20d6fa | 2078 | } |
b36d64df | 2079 | } |
2080 | \f | |
3072d30e | 2081 | |
5f5d4cd1 | 2082 | /* Print out RTL-specific basic block information (live information |
5147ec07 | 2083 | at start and end with TDF_DETAILS). FLAGS are the TDF_* masks |
2084 | documented in dumpfile.h. */ | |
b36d64df | 2085 | |
028f8cc7 | 2086 | static void |
5147ec07 | 2087 | rtl_dump_bb (FILE *outf, basic_block bb, int indent, int flags) |
b36d64df | 2088 | { |
2089 | rtx insn; | |
2090 | rtx last; | |
5f5d4cd1 | 2091 | char *s_indent; |
b36d64df | 2092 | |
f780cc25 | 2093 | s_indent = (char *) alloca ((size_t) indent + 1); |
4acc30e5 | 2094 | memset (s_indent, ' ', (size_t) indent); |
5f5d4cd1 | 2095 | s_indent[indent] = '\0'; |
48e1416a | 2096 | |
5147ec07 | 2097 | if (df && (flags & TDF_DETAILS)) |
3072d30e | 2098 | { |
2099 | df_dump_top (bb, outf); | |
2100 | putc ('\n', outf); | |
2101 | } | |
b36d64df | 2102 | |
4c2112a3 | 2103 | if (bb->index != ENTRY_BLOCK && bb->index != EXIT_BLOCK) |
2104 | for (insn = BB_HEAD (bb), last = NEXT_INSN (BB_END (bb)); insn != last; | |
2105 | insn = NEXT_INSN (insn)) | |
5147ec07 | 2106 | { |
ea9538fb | 2107 | if (flags & TDF_DETAILS) |
2108 | df_dump_insn_top (insn, outf); | |
5147ec07 | 2109 | if (! (flags & TDF_SLIM)) |
2110 | print_rtl_single (outf, insn); | |
2111 | else | |
2112 | dump_insn_slim (outf, insn); | |
ea9538fb | 2113 | if (flags & TDF_DETAILS) |
2114 | df_dump_insn_bottom (insn, outf); | |
5147ec07 | 2115 | } |
2116 | ||
2117 | if (df && (flags & TDF_DETAILS)) | |
3072d30e | 2118 | { |
2119 | df_dump_bottom (bb, outf); | |
2120 | putc ('\n', outf); | |
2121 | } | |
2122 | ||
b36d64df | 2123 | } |
2124 | \f | |
bec2cf98 | 2125 | /* Like dump_function_to_file, but for RTL. Print out dataflow information |
2126 | for the start of each basic block. FLAGS are the TDF_* masks documented | |
2127 | in dumpfile.h. */ | |
b36d64df | 2128 | |
2129 | void | |
5147ec07 | 2130 | print_rtl_with_bb (FILE *outf, const_rtx rtx_first, int flags) |
b36d64df | 2131 | { |
1f1872fd | 2132 | const_rtx tmp_rtx; |
b36d64df | 2133 | if (rtx_first == 0) |
2134 | fprintf (outf, "(nil)\n"); | |
2135 | else | |
2136 | { | |
b36d64df | 2137 | enum bb_state { NOT_IN_BB, IN_ONE_BB, IN_MULTIPLE_BB }; |
2138 | int max_uid = get_max_uid (); | |
4c36ffe6 | 2139 | basic_block *start = XCNEWVEC (basic_block, max_uid); |
2140 | basic_block *end = XCNEWVEC (basic_block, max_uid); | |
2141 | enum bb_state *in_bb_p = XCNEWVEC (enum bb_state, max_uid); | |
4c26117a | 2142 | basic_block bb; |
2143 | ||
bec2cf98 | 2144 | /* After freeing the CFG, we still have BLOCK_FOR_INSN set on most |
2145 | insns, but the CFG is not maintained so the basic block info | |
2146 | is not reliable. Therefore it's omitted from the dumps. */ | |
2147 | if (! (cfun->curr_properties & PROP_cfg)) | |
2148 | flags &= ~TDF_BLOCKS; | |
2149 | ||
3072d30e | 2150 | if (df) |
2151 | df_dump_start (outf); | |
2152 | ||
bec2cf98 | 2153 | if (flags & TDF_BLOCKS) |
b36d64df | 2154 | { |
7a46197b | 2155 | FOR_EACH_BB_REVERSE_FN (bb, cfun) |
b36d64df | 2156 | { |
bec2cf98 | 2157 | rtx x; |
2158 | ||
2159 | start[INSN_UID (BB_HEAD (bb))] = bb; | |
2160 | end[INSN_UID (BB_END (bb))] = bb; | |
2161 | for (x = BB_HEAD (bb); x != NULL_RTX; x = NEXT_INSN (x)) | |
2162 | { | |
2163 | enum bb_state state = IN_MULTIPLE_BB; | |
5cc577b6 | 2164 | |
bec2cf98 | 2165 | if (in_bb_p[INSN_UID (x)] == NOT_IN_BB) |
2166 | state = IN_ONE_BB; | |
2167 | in_bb_p[INSN_UID (x)] = state; | |
b36d64df | 2168 | |
bec2cf98 | 2169 | if (x == BB_END (bb)) |
2170 | break; | |
2171 | } | |
b36d64df | 2172 | } |
2173 | } | |
2174 | ||
2175 | for (tmp_rtx = rtx_first; NULL != tmp_rtx; tmp_rtx = NEXT_INSN (tmp_rtx)) | |
2176 | { | |
bec2cf98 | 2177 | if (flags & TDF_BLOCKS) |
2178 | { | |
2179 | bb = start[INSN_UID (tmp_rtx)]; | |
2180 | if (bb != NULL) | |
2181 | { | |
2182 | dump_bb_info (outf, bb, 0, dump_flags | TDF_COMMENT, true, false); | |
2183 | if (df && (flags & TDF_DETAILS)) | |
2184 | df_dump_top (bb, outf); | |
2185 | } | |
b36d64df | 2186 | |
bec2cf98 | 2187 | if (in_bb_p[INSN_UID (tmp_rtx)] == NOT_IN_BB |
2188 | && !NOTE_P (tmp_rtx) | |
2189 | && !BARRIER_P (tmp_rtx)) | |
2190 | fprintf (outf, ";; Insn is not within a basic block\n"); | |
2191 | else if (in_bb_p[INSN_UID (tmp_rtx)] == IN_MULTIPLE_BB) | |
2192 | fprintf (outf, ";; Insn is in multiple basic blocks\n"); | |
2193 | } | |
b36d64df | 2194 | |
ea9538fb | 2195 | if (flags & TDF_DETAILS) |
2196 | df_dump_insn_top (tmp_rtx, outf); | |
5147ec07 | 2197 | if (! (flags & TDF_SLIM)) |
2198 | print_rtl_single (outf, tmp_rtx); | |
2199 | else | |
2200 | dump_insn_slim (outf, tmp_rtx); | |
ea9538fb | 2201 | if (flags & TDF_DETAILS) |
2202 | df_dump_insn_bottom (tmp_rtx, outf); | |
b36d64df | 2203 | |
bec2cf98 | 2204 | if (flags & TDF_BLOCKS) |
2205 | { | |
2206 | bb = end[INSN_UID (tmp_rtx)]; | |
2207 | if (bb != NULL) | |
2208 | { | |
2209 | dump_bb_info (outf, bb, 0, dump_flags | TDF_COMMENT, false, true); | |
2210 | if (df && (flags & TDF_DETAILS)) | |
2211 | df_dump_bottom (bb, outf); | |
a30975d4 | 2212 | putc ('\n', outf); |
bec2cf98 | 2213 | } |
2214 | } | |
b36d64df | 2215 | } |
2216 | ||
2217 | free (start); | |
2218 | free (end); | |
2219 | free (in_bb_p); | |
2220 | } | |
b36d64df | 2221 | } |
2222 | \f | |
4a020a8c | 2223 | /* Update the branch probability of BB if a REG_BR_PROB is present. */ |
2224 | ||
f884e43f | 2225 | void |
4c9e08a4 | 2226 | update_br_prob_note (basic_block bb) |
f884e43f | 2227 | { |
2228 | rtx note; | |
6d7dc5b9 | 2229 | if (!JUMP_P (BB_END (bb))) |
f884e43f | 2230 | return; |
5496dbfc | 2231 | note = find_reg_note (BB_END (bb), REG_BR_PROB, NULL_RTX); |
9eb946de | 2232 | if (!note || XINT (note, 0) == BRANCH_EDGE (bb)->probability) |
f884e43f | 2233 | return; |
9eb946de | 2234 | XINT (note, 0) = BRANCH_EDGE (bb)->probability; |
f884e43f | 2235 | } |
5d65a39c | 2236 | |
2237 | /* Get the last insn associated with block BB (that includes barriers and | |
2238 | tablejumps after BB). */ | |
2239 | rtx | |
2240 | get_last_bb_insn (basic_block bb) | |
2241 | { | |
2242 | rtx tmp; | |
2243 | rtx end = BB_END (bb); | |
2244 | ||
2245 | /* Include any jump table following the basic block. */ | |
2246 | if (tablejump_p (end, NULL, &tmp)) | |
2247 | end = tmp; | |
2248 | ||
2249 | /* Include any barriers that may follow the basic block. */ | |
c4d13c5c | 2250 | tmp = next_nonnote_insn_bb (end); |
5d65a39c | 2251 | while (tmp && BARRIER_P (tmp)) |
2252 | { | |
2253 | end = tmp; | |
c4d13c5c | 2254 | tmp = next_nonnote_insn_bb (end); |
5d65a39c | 2255 | } |
2256 | ||
2257 | return end; | |
2258 | } | |
812ca88e | 2259 | |
80adc5a6 | 2260 | /* Sanity check partition hotness to ensure that basic blocks in |
2261 | Â the cold partition don't dominate basic blocks in the hot partition. | |
2262 | If FLAG_ONLY is true, report violations as errors. Otherwise | |
2263 | re-mark the dominated blocks as cold, since this is run after | |
2264 | cfg optimizations that may make hot blocks previously reached | |
2265 | by both hot and cold blocks now only reachable along cold paths. */ | |
2266 | ||
2267 | static vec<basic_block> | |
2268 | find_partition_fixes (bool flag_only) | |
2269 | { | |
2270 | basic_block bb; | |
2271 | vec<basic_block> bbs_in_cold_partition = vNULL; | |
2272 | vec<basic_block> bbs_to_fix = vNULL; | |
2273 | ||
2274 | /* Callers check this. */ | |
2275 | gcc_checking_assert (crtl->has_bb_partition); | |
2276 | ||
fc00614f | 2277 | FOR_EACH_BB_FN (bb, cfun) |
80adc5a6 | 2278 | if ((BB_PARTITION (bb) == BB_COLD_PARTITION)) |
2279 | bbs_in_cold_partition.safe_push (bb); | |
2280 | ||
2281 | if (bbs_in_cold_partition.is_empty ()) | |
2282 | return vNULL; | |
2283 | ||
2284 | bool dom_calculated_here = !dom_info_available_p (CDI_DOMINATORS); | |
2285 | ||
2286 | if (dom_calculated_here) | |
2287 | calculate_dominance_info (CDI_DOMINATORS); | |
2288 | ||
2289 | while (! bbs_in_cold_partition.is_empty ()) | |
2290 | { | |
2291 | bb = bbs_in_cold_partition.pop (); | |
2292 | /* Any blocks dominated by a block in the cold section | |
2293 | must also be cold. */ | |
2294 | basic_block son; | |
2295 | for (son = first_dom_son (CDI_DOMINATORS, bb); | |
2296 | son; | |
2297 | son = next_dom_son (CDI_DOMINATORS, son)) | |
2298 | { | |
2299 | /* If son is not yet cold, then mark it cold here and | |
2300 | enqueue it for further processing. */ | |
2301 | if ((BB_PARTITION (son) != BB_COLD_PARTITION)) | |
2302 | { | |
2303 | if (flag_only) | |
2304 | error ("non-cold basic block %d dominated " | |
2305 | "by a block in the cold partition (%d)", son->index, bb->index); | |
2306 | else | |
2307 | BB_SET_PARTITION (son, BB_COLD_PARTITION); | |
2308 | bbs_to_fix.safe_push (son); | |
2309 | bbs_in_cold_partition.safe_push (son); | |
2310 | } | |
2311 | } | |
2312 | } | |
2313 | ||
2314 | if (dom_calculated_here) | |
2315 | free_dominance_info (CDI_DOMINATORS); | |
2316 | ||
2317 | return bbs_to_fix; | |
2318 | } | |
2319 | ||
2320 | /* Perform cleanup on the hot/cold bb partitioning after optimization | |
2321 | passes that modify the cfg. */ | |
2322 | ||
2323 | void | |
2324 | fixup_partitions (void) | |
2325 | { | |
2326 | basic_block bb; | |
2327 | ||
2328 | if (!crtl->has_bb_partition) | |
2329 | return; | |
2330 | ||
2331 | /* Delete any blocks that became unreachable and weren't | |
2332 | already cleaned up, for example during edge forwarding | |
2333 | and convert_jumps_to_returns. This will expose more | |
2334 | opportunities for fixing the partition boundaries here. | |
2335 | Also, the calculation of the dominance graph during verification | |
2336 | will assert if there are unreachable nodes. */ | |
2337 | delete_unreachable_blocks (); | |
2338 | ||
2339 | /* If there are partitions, do a sanity check on them: A basic block in | |
2340 | Â a cold partition cannot dominate a basic block in a hot partition. | |
2341 | Fixup any that now violate this requirement, as a result of edge | |
2342 | forwarding and unreachable block deletion. Â */ | |
2343 | vec<basic_block> bbs_to_fix = find_partition_fixes (false); | |
2344 | ||
2345 | /* Do the partition fixup after all necessary blocks have been converted to | |
2346 | cold, so that we only update the region crossings the minimum number of | |
2347 | places, which can require forcing edges to be non fallthru. */ | |
2348 | while (! bbs_to_fix.is_empty ()) | |
2349 | { | |
2350 | bb = bbs_to_fix.pop (); | |
2351 | fixup_new_cold_bb (bb); | |
2352 | } | |
2353 | } | |
2354 | ||
812ca88e | 2355 | /* Verify, in the basic block chain, that there is at most one switch |
2356 | between hot/cold partitions. This condition will not be true until | |
2357 | after reorder_basic_blocks is called. */ | |
2358 | ||
4bf32a77 | 2359 | static int |
812ca88e | 2360 | verify_hot_cold_block_grouping (void) |
2361 | { | |
2362 | basic_block bb; | |
2363 | int err = 0; | |
2364 | bool switched_sections = false; | |
2365 | int current_partition = BB_UNPARTITIONED; | |
2366 | ||
aa78dca5 | 2367 | /* Even after bb reordering is complete, we go into cfglayout mode |
2368 | again (in compgoto). Ensure we don't call this before going back | |
2369 | into linearized RTL when any layout fixes would have been committed. */ | |
2370 | if (!crtl->bb_reorder_complete | |
9af5ce0c | 2371 | || current_ir_type () != IR_RTL_CFGRTL) |
4bf32a77 | 2372 | return err; |
812ca88e | 2373 | |
fc00614f | 2374 | FOR_EACH_BB_FN (bb, cfun) |
812ca88e | 2375 | { |
2376 | if (current_partition != BB_UNPARTITIONED | |
2377 | && BB_PARTITION (bb) != current_partition) | |
2378 | { | |
2379 | if (switched_sections) | |
2380 | { | |
2381 | error ("multiple hot/cold transitions found (bb %i)", | |
2382 | bb->index); | |
2383 | err = 1; | |
2384 | } | |
2385 | else | |
2386 | switched_sections = true; | |
2387 | ||
2388 | if (!crtl->has_bb_partition) | |
2389 | error ("partition found but function partition flag not set"); | |
2390 | } | |
2391 | current_partition = BB_PARTITION (bb); | |
2392 | } | |
2393 | ||
4bf32a77 | 2394 | return err; |
812ca88e | 2395 | } |
f884e43f | 2396 | \f |
b36d64df | 2397 | |
4bf32a77 | 2398 | /* Perform several checks on the edges out of each block, such as |
2399 | the consistency of the branch probabilities, the correctness | |
2400 | of hot/cold partition crossing edges, and the number of expected | |
80adc5a6 | 2401 | successor edges. Also verify that the dominance relationship |
2402 | between hot/cold blocks is sane. */ | |
5f5d4cd1 | 2403 | |
028f8cc7 | 2404 | static int |
4bf32a77 | 2405 | rtl_verify_edges (void) |
b36d64df | 2406 | { |
028f8cc7 | 2407 | int err = 0; |
d207f783 | 2408 | basic_block bb; |
b36d64df | 2409 | |
7a46197b | 2410 | FOR_EACH_BB_REVERSE_FN (bb, cfun) |
b36d64df | 2411 | { |
103dfb10 | 2412 | int n_fallthru = 0, n_branch = 0, n_abnormal_call = 0, n_sibcall = 0; |
2413 | int n_eh = 0, n_abnormal = 0; | |
e6261ab0 | 2414 | edge e, fallthru = NULL; |
cd665a06 | 2415 | edge_iterator ei; |
4bf32a77 | 2416 | rtx note; |
aa78dca5 | 2417 | bool has_crossing_edge = false; |
b36d64df | 2418 | |
e6d1500f | 2419 | if (JUMP_P (BB_END (bb)) |
5496dbfc | 2420 | && (note = find_reg_note (BB_END (bb), REG_BR_PROB, NULL_RTX)) |
cd665a06 | 2421 | && EDGE_COUNT (bb->succs) >= 2 |
5496dbfc | 2422 | && any_condjump_p (BB_END (bb))) |
a2e42321 | 2423 | { |
9eb946de | 2424 | if (XINT (note, 0) != BRANCH_EDGE (bb)->probability |
f26d8580 | 2425 | && profile_status_for_fn (cfun) != PROFILE_ABSENT) |
a2e42321 | 2426 | { |
9eb946de | 2427 | error ("verify_flow_info: REG_BR_PROB does not match cfg %i %i", |
2428 | XINT (note, 0), BRANCH_EDGE (bb)->probability); | |
a2e42321 | 2429 | err = 1; |
2430 | } | |
2431 | } | |
4bf32a77 | 2432 | |
cd665a06 | 2433 | FOR_EACH_EDGE (e, ei, bb->succs) |
b36d64df | 2434 | { |
f59cbcbf | 2435 | bool is_crossing; |
2436 | ||
b36d64df | 2437 | if (e->flags & EDGE_FALLTHRU) |
f59cbcbf | 2438 | n_fallthru++, fallthru = e; |
2439 | ||
2440 | is_crossing = (BB_PARTITION (e->src) != BB_PARTITION (e->dest) | |
34154e27 | 2441 | && e->src != ENTRY_BLOCK_PTR_FOR_FN (cfun) |
2442 | && e->dest != EXIT_BLOCK_PTR_FOR_FN (cfun)); | |
aa78dca5 | 2443 | has_crossing_edge |= is_crossing; |
f59cbcbf | 2444 | if (e->flags & EDGE_CROSSING) |
4f18499c | 2445 | { |
f59cbcbf | 2446 | if (!is_crossing) |
2447 | { | |
2448 | error ("EDGE_CROSSING incorrectly set across same section"); | |
2449 | err = 1; | |
2450 | } | |
2451 | if (e->flags & EDGE_FALLTHRU) | |
2452 | { | |
103dfb10 | 2453 | error ("fallthru edge crosses section boundary in bb %i", |
4f18499c | 2454 | e->src->index); |
2455 | err = 1; | |
2456 | } | |
f59cbcbf | 2457 | if (e->flags & EDGE_EH) |
2458 | { | |
103dfb10 | 2459 | error ("EH edge crosses section boundary in bb %i", |
f59cbcbf | 2460 | e->src->index); |
2461 | err = 1; | |
2462 | } | |
aa78dca5 | 2463 | if (JUMP_P (BB_END (bb)) |
2464 | && !find_reg_note (BB_END (bb), REG_CROSSING_JUMP, NULL_RTX)) | |
2465 | { | |
2466 | error ("No region crossing jump at section boundary in bb %i", | |
2467 | bb->index); | |
2468 | err = 1; | |
2469 | } | |
f59cbcbf | 2470 | } |
2471 | else if (is_crossing) | |
2472 | { | |
2473 | error ("EDGE_CROSSING missing across section boundary"); | |
2474 | err = 1; | |
4f18499c | 2475 | } |
fb20d6fa | 2476 | |
7f42fe24 | 2477 | if ((e->flags & ~(EDGE_DFS_BACK |
2478 | | EDGE_CAN_FALLTHRU | |
2479 | | EDGE_IRREDUCIBLE_LOOP | |
f50b5bd0 | 2480 | | EDGE_LOOP_EXIT |
acc48fa6 | 2481 | | EDGE_CROSSING |
2482 | | EDGE_PRESERVE)) == 0) | |
fb20d6fa | 2483 | n_branch++; |
2484 | ||
2485 | if (e->flags & EDGE_ABNORMAL_CALL) | |
103dfb10 | 2486 | n_abnormal_call++; |
2487 | ||
2488 | if (e->flags & EDGE_SIBCALL) | |
2489 | n_sibcall++; | |
fb20d6fa | 2490 | |
2491 | if (e->flags & EDGE_EH) | |
2492 | n_eh++; | |
103dfb10 | 2493 | |
2494 | if (e->flags & EDGE_ABNORMAL) | |
fb20d6fa | 2495 | n_abnormal++; |
b36d64df | 2496 | } |
5cc577b6 | 2497 | |
aa78dca5 | 2498 | if (!has_crossing_edge |
2499 | && find_reg_note (BB_END (bb), REG_CROSSING_JUMP, NULL_RTX)) | |
2500 | { | |
2501 | print_rtl_with_bb (stderr, get_insns (), TDF_RTL | TDF_BLOCKS | TDF_DETAILS); | |
2502 | error ("Region crossing jump across same section in bb %i", | |
2503 | bb->index); | |
2504 | err = 1; | |
2505 | } | |
2506 | ||
e38def9c | 2507 | if (n_eh && !find_reg_note (BB_END (bb), REG_EH_REGION, NULL_RTX)) |
fb20d6fa | 2508 | { |
103dfb10 | 2509 | error ("missing REG_EH_REGION note at the end of bb %i", bb->index); |
fb20d6fa | 2510 | err = 1; |
2511 | } | |
e38def9c | 2512 | if (n_eh > 1) |
2513 | { | |
103dfb10 | 2514 | error ("too many exception handling edges in bb %i", bb->index); |
e38def9c | 2515 | err = 1; |
2516 | } | |
fb20d6fa | 2517 | if (n_branch |
6d7dc5b9 | 2518 | && (!JUMP_P (BB_END (bb)) |
5496dbfc | 2519 | || (n_branch > 1 && (any_uncondjump_p (BB_END (bb)) |
2520 | || any_condjump_p (BB_END (bb)))))) | |
fb20d6fa | 2521 | { |
0a81f5a0 | 2522 | error ("too many outgoing branch edges from bb %i", bb->index); |
fb20d6fa | 2523 | err = 1; |
2524 | } | |
5496dbfc | 2525 | if (n_fallthru && any_uncondjump_p (BB_END (bb))) |
fb20d6fa | 2526 | { |
103dfb10 | 2527 | error ("fallthru edge after unconditional jump in bb %i", bb->index); |
fb20d6fa | 2528 | err = 1; |
2529 | } | |
5496dbfc | 2530 | if (n_branch != 1 && any_uncondjump_p (BB_END (bb))) |
fb20d6fa | 2531 | { |
103dfb10 | 2532 | error ("wrong number of branch edges after unconditional jump" |
2533 | " in bb %i", bb->index); | |
fb20d6fa | 2534 | err = 1; |
2535 | } | |
5496dbfc | 2536 | if (n_branch != 1 && any_condjump_p (BB_END (bb)) |
8345ac1a | 2537 | && JUMP_LABEL (BB_END (bb)) != BB_HEAD (fallthru->dest)) |
fb20d6fa | 2538 | { |
103dfb10 | 2539 | error ("wrong amount of branch edges after conditional jump" |
2540 | " in bb %i", bb->index); | |
2541 | err = 1; | |
2542 | } | |
2543 | if (n_abnormal_call && !CALL_P (BB_END (bb))) | |
2544 | { | |
2545 | error ("abnormal call edges for non-call insn in bb %i", bb->index); | |
fb20d6fa | 2546 | err = 1; |
2547 | } | |
103dfb10 | 2548 | if (n_sibcall && !CALL_P (BB_END (bb))) |
fb20d6fa | 2549 | { |
103dfb10 | 2550 | error ("sibcall edges for non-call insn in bb %i", bb->index); |
fb20d6fa | 2551 | err = 1; |
2552 | } | |
103dfb10 | 2553 | if (n_abnormal > n_eh |
2554 | && !(CALL_P (BB_END (bb)) | |
2555 | && n_abnormal == n_abnormal_call + n_sibcall) | |
6d7dc5b9 | 2556 | && (!JUMP_P (BB_END (bb)) |
5496dbfc | 2557 | || any_condjump_p (BB_END (bb)) |
2558 | || any_uncondjump_p (BB_END (bb)))) | |
fb20d6fa | 2559 | { |
0a81f5a0 | 2560 | error ("abnormal edges for no purpose in bb %i", bb->index); |
fb20d6fa | 2561 | err = 1; |
2562 | } | |
4bf32a77 | 2563 | } |
db34a109 | 2564 | |
80adc5a6 | 2565 | /* If there are partitions, do a sanity check on them: A basic block in |
2566 | Â a cold partition cannot dominate a basic block in a hot partition. Â */ | |
2567 | if (crtl->has_bb_partition && !err) | |
2568 | { | |
2569 | vec<basic_block> bbs_to_fix = find_partition_fixes (true); | |
2570 | err = !bbs_to_fix.is_empty (); | |
2571 | } | |
2572 | ||
4bf32a77 | 2573 | /* Clean up. */ |
2574 | return err; | |
2575 | } | |
5cc577b6 | 2576 | |
4bf32a77 | 2577 | /* Checks on the instructions within blocks. Currently checks that each |
2578 | block starts with a basic block note, and that basic block notes and | |
2579 | control flow jumps are not found in the middle of the block. */ | |
b36d64df | 2580 | |
4bf32a77 | 2581 | static int |
2582 | rtl_verify_bb_insns (void) | |
2583 | { | |
2584 | rtx x; | |
2585 | int err = 0; | |
2586 | basic_block bb; | |
2587 | ||
7a46197b | 2588 | FOR_EACH_BB_REVERSE_FN (bb, cfun) |
4bf32a77 | 2589 | { |
2590 | /* Now check the header of basic | |
a0c938f0 | 2591 | block. It ought to contain optional CODE_LABEL followed |
b36d64df | 2592 | by NOTE_BASIC_BLOCK. */ |
5496dbfc | 2593 | x = BB_HEAD (bb); |
6d7dc5b9 | 2594 | if (LABEL_P (x)) |
b36d64df | 2595 | { |
5496dbfc | 2596 | if (BB_END (bb) == x) |
b36d64df | 2597 | { |
2598 | error ("NOTE_INSN_BASIC_BLOCK is missing for block %d", | |
b3d6de89 | 2599 | bb->index); |
b36d64df | 2600 | err = 1; |
2601 | } | |
5cc577b6 | 2602 | |
b36d64df | 2603 | x = NEXT_INSN (x); |
2604 | } | |
5cc577b6 | 2605 | |
b36d64df | 2606 | if (!NOTE_INSN_BASIC_BLOCK_P (x) || NOTE_BASIC_BLOCK (x) != bb) |
2607 | { | |
2608 | error ("NOTE_INSN_BASIC_BLOCK is missing for block %d", | |
b3d6de89 | 2609 | bb->index); |
b36d64df | 2610 | err = 1; |
2611 | } | |
2612 | ||
5496dbfc | 2613 | if (BB_END (bb) == x) |
f3e2a363 | 2614 | /* Do checks for empty blocks here. */ |
5cc577b6 | 2615 | ; |
b36d64df | 2616 | else |
5cc577b6 | 2617 | for (x = NEXT_INSN (x); x; x = NEXT_INSN (x)) |
2618 | { | |
2619 | if (NOTE_INSN_BASIC_BLOCK_P (x)) | |
2620 | { | |
2621 | error ("NOTE_INSN_BASIC_BLOCK %d in middle of basic block %d", | |
b3d6de89 | 2622 | INSN_UID (x), bb->index); |
5cc577b6 | 2623 | err = 1; |
2624 | } | |
2625 | ||
5496dbfc | 2626 | if (x == BB_END (bb)) |
5cc577b6 | 2627 | break; |
b36d64df | 2628 | |
aaf52ffb | 2629 | if (control_flow_insn_p (x)) |
5cc577b6 | 2630 | { |
b3d6de89 | 2631 | error ("in basic block %d:", bb->index); |
5cc577b6 | 2632 | fatal_insn ("flow control insn inside a basic block", x); |
2633 | } | |
2634 | } | |
b36d64df | 2635 | } |
2636 | ||
4bf32a77 | 2637 | /* Clean up. */ |
2638 | return err; | |
2639 | } | |
2640 | ||
2641 | /* Verify that block pointers for instructions in basic blocks, headers and | |
2642 | footers are set appropriately. */ | |
2643 | ||
2644 | static int | |
2645 | rtl_verify_bb_pointers (void) | |
2646 | { | |
2647 | int err = 0; | |
2648 | basic_block bb; | |
2649 | ||
2650 | /* Check the general integrity of the basic blocks. */ | |
7a46197b | 2651 | FOR_EACH_BB_REVERSE_FN (bb, cfun) |
4bf32a77 | 2652 | { |
2653 | rtx insn; | |
2654 | ||
2655 | if (!(bb->flags & BB_RTL)) | |
2656 | { | |
2657 | error ("BB_RTL flag not set for block %d", bb->index); | |
2658 | err = 1; | |
2659 | } | |
2660 | ||
2661 | FOR_BB_INSNS (bb, insn) | |
2662 | if (BLOCK_FOR_INSN (insn) != bb) | |
2663 | { | |
2664 | error ("insn %d basic block pointer is %d, should be %d", | |
2665 | INSN_UID (insn), | |
2666 | BLOCK_FOR_INSN (insn) ? BLOCK_FOR_INSN (insn)->index : 0, | |
2667 | bb->index); | |
2668 | err = 1; | |
2669 | } | |
2670 | ||
2671 | for (insn = BB_HEADER (bb); insn; insn = NEXT_INSN (insn)) | |
2672 | if (!BARRIER_P (insn) | |
2673 | && BLOCK_FOR_INSN (insn) != NULL) | |
2674 | { | |
2675 | error ("insn %d in header of bb %d has non-NULL basic block", | |
2676 | INSN_UID (insn), bb->index); | |
2677 | err = 1; | |
2678 | } | |
2679 | for (insn = BB_FOOTER (bb); insn; insn = NEXT_INSN (insn)) | |
2680 | if (!BARRIER_P (insn) | |
2681 | && BLOCK_FOR_INSN (insn) != NULL) | |
2682 | { | |
2683 | error ("insn %d in footer of bb %d has non-NULL basic block", | |
2684 | INSN_UID (insn), bb->index); | |
2685 | err = 1; | |
2686 | } | |
2687 | } | |
812ca88e | 2688 | |
028f8cc7 | 2689 | /* Clean up. */ |
028f8cc7 | 2690 | return err; |
2691 | } | |
5cc577b6 | 2692 | |
028f8cc7 | 2693 | /* Verify the CFG and RTL consistency common for both underlying RTL and |
2694 | cfglayout RTL. | |
5cc577b6 | 2695 | |
028f8cc7 | 2696 | Currently it does following checks: |
4bf32a77 | 2697 | |
2698 | - overlapping of basic blocks | |
2699 | - insns with wrong BLOCK_FOR_INSN pointers | |
2700 | - headers of basic blocks (the NOTE_INSN_BASIC_BLOCK note) | |
2701 | - tails of basic blocks (ensure that boundary is necessary) | |
2702 | - scans body of the basic block for JUMP_INSN, CODE_LABEL | |
2703 | and NOTE_INSN_BASIC_BLOCK | |
2704 | - verify that no fall_thru edge crosses hot/cold partition boundaries | |
2705 | - verify that there are no pending RTL branch predictions | |
80adc5a6 | 2706 | - verify that hot blocks are not dominated by cold blocks |
4bf32a77 | 2707 | |
2708 | In future it can be extended check a lot of other stuff as well | |
2709 | (reachability of basic blocks, life information, etc. etc.). */ | |
fcde5c9e | 2710 | |
028f8cc7 | 2711 | static int |
4bf32a77 | 2712 | rtl_verify_flow_info_1 (void) |
2713 | { | |
2714 | int err = 0; | |
2715 | ||
2716 | err |= rtl_verify_bb_pointers (); | |
2717 | ||
2718 | err |= rtl_verify_bb_insns (); | |
2719 | ||
2720 | err |= rtl_verify_edges (); | |
2721 | ||
4bf32a77 | 2722 | return err; |
2723 | } | |
2724 | ||
2725 | /* Walk the instruction chain and verify that bb head/end pointers | |
2726 | are correct, and that instructions are in exactly one bb and have | |
2727 | correct block pointers. */ | |
2728 | ||
2729 | static int | |
2730 | rtl_verify_bb_insn_chain (void) | |
028f8cc7 | 2731 | { |
2732 | basic_block bb; | |
4bf32a77 | 2733 | int err = 0; |
028f8cc7 | 2734 | rtx x; |
fcde5c9e | 2735 | rtx last_head = get_last_insn (); |
2736 | basic_block *bb_info; | |
fcde5c9e | 2737 | const int max_uid = get_max_uid (); |
2738 | ||
2739 | bb_info = XCNEWVEC (basic_block, max_uid); | |
b36d64df | 2740 | |
7a46197b | 2741 | FOR_EACH_BB_REVERSE_FN (bb, cfun) |
028f8cc7 | 2742 | { |
fcde5c9e | 2743 | rtx head = BB_HEAD (bb); |
2744 | rtx end = BB_END (bb); | |
cd665a06 | 2745 | |
fcde5c9e | 2746 | for (x = last_head; x != NULL_RTX; x = PREV_INSN (x)) |
39257eb5 | 2747 | { |
2748 | /* Verify the end of the basic block is in the INSN chain. */ | |
2749 | if (x == end) | |
2750 | break; | |
2751 | ||
4bf32a77 | 2752 | /* And that the code outside of basic blocks has NULL bb field. */ |
2753 | if (!BARRIER_P (x) | |
2754 | && BLOCK_FOR_INSN (x) != NULL) | |
2755 | { | |
2756 | error ("insn %d outside of basic blocks has non-NULL bb field", | |
2757 | INSN_UID (x)); | |
2758 | err = 1; | |
2759 | } | |
39257eb5 | 2760 | } |
fcde5c9e | 2761 | |
2762 | if (!x) | |
2763 | { | |
2764 | error ("end insn %d for block %d not found in the insn stream", | |
2765 | INSN_UID (end), bb->index); | |
2766 | err = 1; | |
2767 | } | |
2768 | ||
2769 | /* Work backwards from the end to the head of the basic block | |
2770 | to verify the head is in the RTL chain. */ | |
2771 | for (; x != NULL_RTX; x = PREV_INSN (x)) | |
d5043f32 | 2772 | { |
fcde5c9e | 2773 | /* While walking over the insn chain, verify insns appear |
2774 | in only one basic block. */ | |
2775 | if (bb_info[INSN_UID (x)] != NULL) | |
2776 | { | |
2777 | error ("insn %d is in multiple basic blocks (%d and %d)", | |
2778 | INSN_UID (x), bb->index, bb_info[INSN_UID (x)]->index); | |
2779 | err = 1; | |
2780 | } | |
2781 | ||
2782 | bb_info[INSN_UID (x)] = bb; | |
2783 | ||
2784 | if (x == head) | |
2785 | break; | |
2786 | } | |
2787 | if (!x) | |
2788 | { | |
2789 | error ("head insn %d for block %d not found in the insn stream", | |
2790 | INSN_UID (head), bb->index); | |
d5043f32 | 2791 | err = 1; |
2792 | } | |
2793 | ||
39257eb5 | 2794 | last_head = PREV_INSN (x); |
4bf32a77 | 2795 | } |
2796 | ||
2797 | for (x = last_head; x != NULL_RTX; x = PREV_INSN (x)) | |
2798 | { | |
2799 | /* Check that the code before the first basic block has NULL | |
2800 | bb field. */ | |
2801 | if (!BARRIER_P (x) | |
2802 | && BLOCK_FOR_INSN (x) != NULL) | |
2803 | { | |
2804 | error ("insn %d outside of basic blocks has non-NULL bb field", | |
2805 | INSN_UID (x)); | |
2806 | err = 1; | |
2807 | } | |
2808 | } | |
2809 | free (bb_info); | |
2810 | ||
2811 | return err; | |
2812 | } | |
2813 | ||
2814 | /* Verify that fallthru edges point to adjacent blocks in layout order and | |
2815 | that barriers exist after non-fallthru blocks. */ | |
2816 | ||
2817 | static int | |
2818 | rtl_verify_fallthru (void) | |
2819 | { | |
2820 | basic_block bb; | |
2821 | int err = 0; | |
2822 | ||
7a46197b | 2823 | FOR_EACH_BB_REVERSE_FN (bb, cfun) |
4bf32a77 | 2824 | { |
2825 | edge e; | |
fcde5c9e | 2826 | |
7f58c05e | 2827 | e = find_fallthru_edge (bb->succs); |
028f8cc7 | 2828 | if (!e) |
2829 | { | |
2830 | rtx insn; | |
2831 | ||
2832 | /* Ensure existence of barrier in BB with no fallthru edges. */ | |
d2b48f0c | 2833 | for (insn = NEXT_INSN (BB_END (bb)); ; insn = NEXT_INSN (insn)) |
2834 | { | |
2835 | if (!insn || NOTE_INSN_BASIC_BLOCK_P (insn)) | |
028f8cc7 | 2836 | { |
2837 | error ("missing barrier after block %i", bb->index); | |
2838 | err = 1; | |
2839 | break; | |
2840 | } | |
d2b48f0c | 2841 | if (BARRIER_P (insn)) |
2842 | break; | |
2843 | } | |
028f8cc7 | 2844 | } |
34154e27 | 2845 | else if (e->src != ENTRY_BLOCK_PTR_FOR_FN (cfun) |
2846 | && e->dest != EXIT_BLOCK_PTR_FOR_FN (cfun)) | |
a0c938f0 | 2847 | { |
028f8cc7 | 2848 | rtx insn; |
2849 | ||
2850 | if (e->src->next_bb != e->dest) | |
2851 | { | |
2852 | error | |
2853 | ("verify_flow_info: Incorrect blocks for fallthru %i->%i", | |
2854 | e->src->index, e->dest->index); | |
2855 | err = 1; | |
2856 | } | |
2857 | else | |
5496dbfc | 2858 | for (insn = NEXT_INSN (BB_END (e->src)); insn != BB_HEAD (e->dest); |
028f8cc7 | 2859 | insn = NEXT_INSN (insn)) |
ac7d3688 | 2860 | if (BARRIER_P (insn) || INSN_P (insn)) |
028f8cc7 | 2861 | { |
2862 | error ("verify_flow_info: Incorrect fallthru %i->%i", | |
2863 | e->src->index, e->dest->index); | |
2864 | fatal_insn ("wrong insn in the fallthru edge", insn); | |
2865 | err = 1; | |
2866 | } | |
a0c938f0 | 2867 | } |
028f8cc7 | 2868 | } |
b36d64df | 2869 | |
4bf32a77 | 2870 | return err; |
2871 | } | |
2872 | ||
2873 | /* Verify that blocks are laid out in consecutive order. While walking the | |
2874 | instructions, verify that all expected instructions are inside the basic | |
2875 | blocks, and that all returns are followed by barriers. */ | |
2876 | ||
2877 | static int | |
2878 | rtl_verify_bb_layout (void) | |
2879 | { | |
2880 | basic_block bb; | |
2881 | int err = 0; | |
2882 | rtx x; | |
2883 | int num_bb_notes; | |
2884 | const rtx rtx_first = get_insns (); | |
34154e27 | 2885 | basic_block last_bb_seen = ENTRY_BLOCK_PTR_FOR_FN (cfun), curr_bb = NULL; |
fcde5c9e | 2886 | |
b36d64df | 2887 | num_bb_notes = 0; |
34154e27 | 2888 | last_bb_seen = ENTRY_BLOCK_PTR_FOR_FN (cfun); |
4c26117a | 2889 | |
5cc577b6 | 2890 | for (x = rtx_first; x; x = NEXT_INSN (x)) |
b36d64df | 2891 | { |
2892 | if (NOTE_INSN_BASIC_BLOCK_P (x)) | |
2893 | { | |
3c0a32c9 | 2894 | bb = NOTE_BASIC_BLOCK (x); |
5cc577b6 | 2895 | |
b36d64df | 2896 | num_bb_notes++; |
4c26117a | 2897 | if (bb != last_bb_seen->next_bb) |
028f8cc7 | 2898 | internal_error ("basic blocks not laid down consecutively"); |
b36d64df | 2899 | |
028f8cc7 | 2900 | curr_bb = last_bb_seen = bb; |
b36d64df | 2901 | } |
2902 | ||
028f8cc7 | 2903 | if (!curr_bb) |
b36d64df | 2904 | { |
2905 | switch (GET_CODE (x)) | |
2906 | { | |
2907 | case BARRIER: | |
2908 | case NOTE: | |
2909 | break; | |
2910 | ||
2911 | case CODE_LABEL: | |
91f71fa3 | 2912 | /* An ADDR_VEC is placed outside any basic block. */ |
b36d64df | 2913 | if (NEXT_INSN (x) |
971ba038 | 2914 | && JUMP_TABLE_DATA_P (NEXT_INSN (x))) |
5cc577b6 | 2915 | x = NEXT_INSN (x); |
b36d64df | 2916 | |
2917 | /* But in any case, non-deletable labels can appear anywhere. */ | |
2918 | break; | |
2919 | ||
2920 | default: | |
cb8bacb6 | 2921 | fatal_insn ("insn outside basic block", x); |
b36d64df | 2922 | } |
2923 | } | |
2924 | ||
345f9e8c | 2925 | if (JUMP_P (x) |
b36d64df | 2926 | && returnjump_p (x) && ! condjump_p (x) |
8fcc0f14 | 2927 | && ! (next_nonnote_insn (x) && BARRIER_P (next_nonnote_insn (x)))) |
cb8bacb6 | 2928 | fatal_insn ("return not followed by barrier", x); |
4bf32a77 | 2929 | |
5496dbfc | 2930 | if (curr_bb && x == BB_END (curr_bb)) |
028f8cc7 | 2931 | curr_bb = NULL; |
b36d64df | 2932 | } |
2933 | ||
a28770e1 | 2934 | if (num_bb_notes != n_basic_blocks_for_fn (cfun) - NUM_FIXED_BLOCKS) |
b36d64df | 2935 | internal_error |
b3d6de89 | 2936 | ("number of bb notes in insn chain (%d) != n_basic_blocks (%d)", |
a28770e1 | 2937 | num_bb_notes, n_basic_blocks_for_fn (cfun)); |
b36d64df | 2938 | |
028f8cc7 | 2939 | return err; |
b36d64df | 2940 | } |
4bf32a77 | 2941 | |
2942 | /* Verify the CFG and RTL consistency common for both underlying RTL and | |
2943 | cfglayout RTL, plus consistency checks specific to linearized RTL mode. | |
2944 | ||
2945 | Currently it does following checks: | |
2946 | - all checks of rtl_verify_flow_info_1 | |
2947 | - test head/end pointers | |
2948 | - check that blocks are laid out in consecutive order | |
2949 | - check that all insns are in the basic blocks | |
2950 | (except the switch handling code, barriers and notes) | |
2951 | - check that all returns are followed by barriers | |
80adc5a6 | 2952 | - check that all fallthru edge points to the adjacent blocks |
2953 | - verify that there is a single hot/cold partition boundary after bbro */ | |
4bf32a77 | 2954 | |
2955 | static int | |
2956 | rtl_verify_flow_info (void) | |
2957 | { | |
2958 | int err = 0; | |
2959 | ||
2960 | err |= rtl_verify_flow_info_1 (); | |
2961 | ||
2962 | err |= rtl_verify_bb_insn_chain (); | |
2963 | ||
2964 | err |= rtl_verify_fallthru (); | |
2965 | ||
2966 | err |= rtl_verify_bb_layout (); | |
2967 | ||
aa78dca5 | 2968 | err |= verify_hot_cold_block_grouping (); |
2969 | ||
4bf32a77 | 2970 | return err; |
2971 | } | |
b36d64df | 2972 | \f |
4a82352a | 2973 | /* Assume that the preceding pass has possibly eliminated jump instructions |
b36d64df | 2974 | or converted the unconditional jumps. Eliminate the edges from CFG. |
2975 | Return true if any edges are eliminated. */ | |
2976 | ||
2977 | bool | |
4c9e08a4 | 2978 | purge_dead_edges (basic_block bb) |
b36d64df | 2979 | { |
cd665a06 | 2980 | edge e; |
5496dbfc | 2981 | rtx insn = BB_END (bb), note; |
b36d64df | 2982 | bool purged = false; |
cd665a06 | 2983 | bool found; |
2984 | edge_iterator ei; | |
b36d64df | 2985 | |
9845d120 | 2986 | if (DEBUG_INSN_P (insn) && insn != BB_HEAD (bb)) |
2987 | do | |
2988 | insn = PREV_INSN (insn); | |
2989 | while ((DEBUG_INSN_P (insn) || NOTE_P (insn)) && insn != BB_HEAD (bb)); | |
2990 | ||
11808932 | 2991 | /* If this instruction cannot trap, remove REG_EH_REGION notes. */ |
6d7dc5b9 | 2992 | if (NONJUMP_INSN_P (insn) |
11808932 | 2993 | && (note = find_reg_note (insn, REG_EH_REGION, NULL))) |
2994 | { | |
2995 | rtx eqnote; | |
2996 | ||
2997 | if (! may_trap_p (PATTERN (insn)) | |
2998 | || ((eqnote = find_reg_equal_equiv_note (insn)) | |
2999 | && ! may_trap_p (XEXP (eqnote, 0)))) | |
3000 | remove_note (insn, note); | |
3001 | } | |
3002 | ||
f178f44b | 3003 | /* Cleanup abnormal edges caused by exceptions or non-local gotos. */ |
cd665a06 | 3004 | for (ei = ei_start (bb->succs); (e = ei_safe_edge (ei)); ) |
f178f44b | 3005 | { |
e38def9c | 3006 | bool remove = false; |
3007 | ||
04166d08 | 3008 | /* There are three types of edges we need to handle correctly here: EH |
3009 | edges, abnormal call EH edges, and abnormal call non-EH edges. The | |
3010 | latter can appear when nonlocal gotos are used. */ | |
e38def9c | 3011 | if (e->flags & EDGE_ABNORMAL_CALL) |
f178f44b | 3012 | { |
e38def9c | 3013 | if (!CALL_P (insn)) |
3014 | remove = true; | |
3015 | else if (can_nonlocal_goto (insn)) | |
3016 | ; | |
3017 | else if ((e->flags & EDGE_EH) && can_throw_internal (insn)) | |
3018 | ; | |
4c0315d0 | 3019 | else if (flag_tm && find_reg_note (insn, REG_TM, NULL)) |
3020 | ; | |
e38def9c | 3021 | else |
3022 | remove = true; | |
f178f44b | 3023 | } |
e38def9c | 3024 | else if (e->flags & EDGE_EH) |
3025 | remove = !can_throw_internal (insn); | |
3026 | ||
3027 | if (remove) | |
f178f44b | 3028 | { |
e38def9c | 3029 | remove_edge (e); |
3030 | df_set_bb_dirty (bb); | |
3031 | purged = true; | |
f178f44b | 3032 | } |
3033 | else | |
e38def9c | 3034 | ei_next (&ei); |
f178f44b | 3035 | } |
5cc577b6 | 3036 | |
6d7dc5b9 | 3037 | if (JUMP_P (insn)) |
b36d64df | 3038 | { |
3039 | rtx note; | |
3040 | edge b,f; | |
cd665a06 | 3041 | edge_iterator ei; |
5cc577b6 | 3042 | |
b36d64df | 3043 | /* We do care only about conditional jumps and simplejumps. */ |
3044 | if (!any_condjump_p (insn) | |
3045 | && !returnjump_p (insn) | |
3046 | && !simplejump_p (insn)) | |
461eeb14 | 3047 | return purged; |
5cc577b6 | 3048 | |
a2e42321 | 3049 | /* Branch probability/prediction notes are defined only for |
3050 | condjumps. We've possibly turned condjump into simplejump. */ | |
3051 | if (simplejump_p (insn)) | |
3052 | { | |
3053 | note = find_reg_note (insn, REG_BR_PROB, NULL); | |
3054 | if (note) | |
3055 | remove_note (insn, note); | |
3056 | while ((note = find_reg_note (insn, REG_BR_PRED, NULL))) | |
3057 | remove_note (insn, note); | |
3058 | } | |
3059 | ||
cd665a06 | 3060 | for (ei = ei_start (bb->succs); (e = ei_safe_edge (ei)); ) |
b36d64df | 3061 | { |
4270b4b9 | 3062 | /* Avoid abnormal flags to leak from computed jumps turned |
3063 | into simplejumps. */ | |
db34a109 | 3064 | |
a0fb7382 | 3065 | e->flags &= ~EDGE_ABNORMAL; |
4270b4b9 | 3066 | |
14abf923 | 3067 | /* See if this edge is one we should keep. */ |
3068 | if ((e->flags & EDGE_FALLTHRU) && any_condjump_p (insn)) | |
3069 | /* A conditional jump can fall through into the next | |
3070 | block, so we should keep the edge. */ | |
cd665a06 | 3071 | { |
3072 | ei_next (&ei); | |
3073 | continue; | |
3074 | } | |
34154e27 | 3075 | else if (e->dest != EXIT_BLOCK_PTR_FOR_FN (cfun) |
5496dbfc | 3076 | && BB_HEAD (e->dest) == JUMP_LABEL (insn)) |
14abf923 | 3077 | /* If the destination block is the target of the jump, |
3078 | keep the edge. */ | |
cd665a06 | 3079 | { |
3080 | ei_next (&ei); | |
3081 | continue; | |
3082 | } | |
34154e27 | 3083 | else if (e->dest == EXIT_BLOCK_PTR_FOR_FN (cfun) |
3084 | && returnjump_p (insn)) | |
14abf923 | 3085 | /* If the destination block is the exit block, and this |
3086 | instruction is a return, then keep the edge. */ | |
cd665a06 | 3087 | { |
3088 | ei_next (&ei); | |
3089 | continue; | |
3090 | } | |
14abf923 | 3091 | else if ((e->flags & EDGE_EH) && can_throw_internal (insn)) |
3092 | /* Keep the edges that correspond to exceptions thrown by | |
1b64239d | 3093 | this instruction and rematerialize the EDGE_ABNORMAL |
3094 | flag we just cleared above. */ | |
3095 | { | |
3096 | e->flags |= EDGE_ABNORMAL; | |
cd665a06 | 3097 | ei_next (&ei); |
1b64239d | 3098 | continue; |
3099 | } | |
5cc577b6 | 3100 | |
14abf923 | 3101 | /* We do not need this edge. */ |
3072d30e | 3102 | df_set_bb_dirty (bb); |
b36d64df | 3103 | purged = true; |
3104 | remove_edge (e); | |
3105 | } | |
5cc577b6 | 3106 | |
cd665a06 | 3107 | if (EDGE_COUNT (bb->succs) == 0 || !purged) |
461eeb14 | 3108 | return purged; |
5cc577b6 | 3109 | |
450d042a | 3110 | if (dump_file) |
3111 | fprintf (dump_file, "Purged edges from bb %i\n", bb->index); | |
5cc577b6 | 3112 | |
b36d64df | 3113 | if (!optimize) |
3114 | return purged; | |
3115 | ||
3116 | /* Redistribute probabilities. */ | |
ea091dfd | 3117 | if (single_succ_p (bb)) |
b36d64df | 3118 | { |
ea091dfd | 3119 | single_succ_edge (bb)->probability = REG_BR_PROB_BASE; |
3120 | single_succ_edge (bb)->count = bb->count; | |
db34a109 | 3121 | } |
b36d64df | 3122 | else |
3123 | { | |
3124 | note = find_reg_note (insn, REG_BR_PROB, NULL); | |
3125 | if (!note) | |
3126 | return purged; | |
5cc577b6 | 3127 | |
b36d64df | 3128 | b = BRANCH_EDGE (bb); |
3129 | f = FALLTHRU_EDGE (bb); | |
9eb946de | 3130 | b->probability = XINT (note, 0); |
b36d64df | 3131 | f->probability = REG_BR_PROB_BASE - b->probability; |
f9d4b7f4 | 3132 | /* Update these to use GCOV_COMPUTE_SCALE. */ |
b36d64df | 3133 | b->count = bb->count * b->probability / REG_BR_PROB_BASE; |
3134 | f->count = bb->count * f->probability / REG_BR_PROB_BASE; | |
3135 | } | |
5cc577b6 | 3136 | |
b36d64df | 3137 | return purged; |
3138 | } | |
6d7dc5b9 | 3139 | else if (CALL_P (insn) && SIBLING_CALL_P (insn)) |
bf4311e9 | 3140 | { |
3141 | /* First, there should not be any EH or ABCALL edges resulting | |
3142 | from non-local gotos and the like. If there were, we shouldn't | |
3143 | have created the sibcall in the first place. Second, there | |
3144 | should of course never have been a fallthru edge. */ | |
ea091dfd | 3145 | gcc_assert (single_succ_p (bb)); |
3146 | gcc_assert (single_succ_edge (bb)->flags | |
3147 | == (EDGE_SIBCALL | EDGE_ABNORMAL)); | |
bf4311e9 | 3148 | |
3149 | return 0; | |
3150 | } | |
b36d64df | 3151 | |
b36d64df | 3152 | /* If we don't see a jump insn, we don't know exactly why the block would |
3153 | have been broken at this point. Look for a simple, non-fallthru edge, | |
3154 | as these are only created by conditional branches. If we find such an | |
3155 | edge we know that there used to be a jump here and can then safely | |
3156 | remove all non-fallthru edges. */ | |
cd665a06 | 3157 | found = false; |
3158 | FOR_EACH_EDGE (e, ei, bb->succs) | |
3159 | if (! (e->flags & (EDGE_COMPLEX | EDGE_FALLTHRU))) | |
3160 | { | |
3161 | found = true; | |
3162 | break; | |
3163 | } | |
5cc577b6 | 3164 | |
cd665a06 | 3165 | if (!found) |
b36d64df | 3166 | return purged; |
5cc577b6 | 3167 | |
6e81a369 | 3168 | /* Remove all but the fake and fallthru edges. The fake edge may be |
3169 | the only successor for this block in the case of noreturn | |
3170 | calls. */ | |
cd665a06 | 3171 | for (ei = ei_start (bb->succs); (e = ei_safe_edge (ei)); ) |
b36d64df | 3172 | { |
6e81a369 | 3173 | if (!(e->flags & (EDGE_FALLTHRU | EDGE_FAKE))) |
461eeb14 | 3174 | { |
3072d30e | 3175 | df_set_bb_dirty (bb); |
461eeb14 | 3176 | remove_edge (e); |
3177 | purged = true; | |
3178 | } | |
cd665a06 | 3179 | else |
3180 | ei_next (&ei); | |
b36d64df | 3181 | } |
5cc577b6 | 3182 | |
ea091dfd | 3183 | gcc_assert (single_succ_p (bb)); |
5cc577b6 | 3184 | |
ea091dfd | 3185 | single_succ_edge (bb)->probability = REG_BR_PROB_BASE; |
3186 | single_succ_edge (bb)->count = bb->count; | |
b36d64df | 3187 | |
450d042a | 3188 | if (dump_file) |
3189 | fprintf (dump_file, "Purged non-fallthru edges from bb %i\n", | |
b3d6de89 | 3190 | bb->index); |
b36d64df | 3191 | return purged; |
3192 | } | |
3193 | ||
5cc577b6 | 3194 | /* Search all basic blocks for potentially dead edges and purge them. Return |
3195 | true if some edge has been eliminated. */ | |
b36d64df | 3196 | |
3197 | bool | |
94ee50e8 | 3198 | purge_all_dead_edges (void) |
b36d64df | 3199 | { |
4c26117a | 3200 | int purged = false; |
4c26117a | 3201 | basic_block bb; |
0922c912 | 3202 | |
fc00614f | 3203 | FOR_EACH_BB_FN (bb, cfun) |
0922c912 | 3204 | { |
4c26117a | 3205 | bool purged_here = purge_dead_edges (bb); |
5cc577b6 | 3206 | |
0922c912 | 3207 | purged |= purged_here; |
0922c912 | 3208 | } |
5cc577b6 | 3209 | |
b36d64df | 3210 | return purged; |
3211 | } | |
1026363d | 3212 | |
54f21e20 | 3213 | /* This is used by a few passes that emit some instructions after abnormal |
3214 | calls, moving the basic block's end, while they in fact do want to emit | |
3215 | them on the fallthru edge. Look for abnormal call edges, find backward | |
3216 | the call in the block and insert the instructions on the edge instead. | |
3217 | ||
3218 | Similarly, handle instructions throwing exceptions internally. | |
3219 | ||
3220 | Return true when instructions have been found and inserted on edges. */ | |
3221 | ||
3222 | bool | |
3223 | fixup_abnormal_edges (void) | |
3224 | { | |
3225 | bool inserted = false; | |
3226 | basic_block bb; | |
3227 | ||
fc00614f | 3228 | FOR_EACH_BB_FN (bb, cfun) |
54f21e20 | 3229 | { |
3230 | edge e; | |
3231 | edge_iterator ei; | |
3232 | ||
3233 | /* Look for cases we are interested in - calls or instructions causing | |
3234 | exceptions. */ | |
3235 | FOR_EACH_EDGE (e, ei, bb->succs) | |
3236 | if ((e->flags & EDGE_ABNORMAL_CALL) | |
3237 | || ((e->flags & (EDGE_ABNORMAL | EDGE_EH)) | |
3238 | == (EDGE_ABNORMAL | EDGE_EH))) | |
3239 | break; | |
3240 | ||
3241 | if (e && !CALL_P (BB_END (bb)) && !can_throw_internal (BB_END (bb))) | |
3242 | { | |
3243 | rtx insn; | |
3244 | ||
3245 | /* Get past the new insns generated. Allow notes, as the insns | |
3246 | may be already deleted. */ | |
3247 | insn = BB_END (bb); | |
3248 | while ((NONJUMP_INSN_P (insn) || NOTE_P (insn)) | |
3249 | && !can_throw_internal (insn) | |
3250 | && insn != BB_HEAD (bb)) | |
3251 | insn = PREV_INSN (insn); | |
3252 | ||
3253 | if (CALL_P (insn) || can_throw_internal (insn)) | |
3254 | { | |
3255 | rtx stop, next; | |
3256 | ||
3257 | e = find_fallthru_edge (bb->succs); | |
3258 | ||
3259 | stop = NEXT_INSN (BB_END (bb)); | |
3260 | BB_END (bb) = insn; | |
3261 | ||
3262 | for (insn = NEXT_INSN (insn); insn != stop; insn = next) | |
3263 | { | |
3264 | next = NEXT_INSN (insn); | |
3265 | if (INSN_P (insn)) | |
3266 | { | |
3267 | delete_insn (insn); | |
3268 | ||
3269 | /* Sometimes there's still the return value USE. | |
3270 | If it's placed after a trapping call (i.e. that | |
3271 | call is the last insn anyway), we have no fallthru | |
3272 | edge. Simply delete this use and don't try to insert | |
3273 | on the non-existent edge. */ | |
3274 | if (GET_CODE (PATTERN (insn)) != USE) | |
3275 | { | |
3276 | /* We're not deleting it, we're moving it. */ | |
3277 | INSN_DELETED_P (insn) = 0; | |
3278 | PREV_INSN (insn) = NULL_RTX; | |
3279 | NEXT_INSN (insn) = NULL_RTX; | |
3280 | ||
3281 | insert_insn_on_edge (insn, e); | |
3282 | inserted = true; | |
3283 | } | |
3284 | } | |
3285 | else if (!BARRIER_P (insn)) | |
3286 | set_block_for_insn (insn, NULL); | |
3287 | } | |
3288 | } | |
3289 | ||
3290 | /* It may be that we don't find any trapping insn. In this | |
3291 | case we discovered quite late that the insn that had been | |
3292 | marked as can_throw_internal in fact couldn't trap at all. | |
3293 | So we should in fact delete the EH edges out of the block. */ | |
3294 | else | |
3295 | purge_dead_edges (bb); | |
3296 | } | |
3297 | } | |
3298 | ||
3299 | return inserted; | |
3300 | } | |
23a070f3 | 3301 | \f |
3302 | /* Cut the insns from FIRST to LAST out of the insns stream. */ | |
3303 | ||
3304 | rtx | |
3305 | unlink_insn_chain (rtx first, rtx last) | |
3306 | { | |
3307 | rtx prevfirst = PREV_INSN (first); | |
3308 | rtx nextlast = NEXT_INSN (last); | |
3309 | ||
3310 | PREV_INSN (first) = NULL; | |
3311 | NEXT_INSN (last) = NULL; | |
3312 | if (prevfirst) | |
3313 | NEXT_INSN (prevfirst) = nextlast; | |
3314 | if (nextlast) | |
3315 | PREV_INSN (nextlast) = prevfirst; | |
3316 | else | |
3317 | set_last_insn (prevfirst); | |
3318 | if (!prevfirst) | |
3319 | set_first_insn (nextlast); | |
3320 | return first; | |
3321 | } | |
3322 | \f | |
3323 | /* Skip over inter-block insns occurring after BB which are typically | |
3324 | associated with BB (e.g., barriers). If there are any such insns, | |
3325 | we return the last one. Otherwise, we return the end of BB. */ | |
3326 | ||
3327 | static rtx | |
3328 | skip_insns_after_block (basic_block bb) | |
3329 | { | |
3330 | rtx insn, last_insn, next_head, prev; | |
3331 | ||
3332 | next_head = NULL_RTX; | |
34154e27 | 3333 | if (bb->next_bb != EXIT_BLOCK_PTR_FOR_FN (cfun)) |
23a070f3 | 3334 | next_head = BB_HEAD (bb->next_bb); |
3335 | ||
3336 | for (last_insn = insn = BB_END (bb); (insn = NEXT_INSN (insn)) != 0; ) | |
3337 | { | |
3338 | if (insn == next_head) | |
3339 | break; | |
3340 | ||
3341 | switch (GET_CODE (insn)) | |
3342 | { | |
3343 | case BARRIER: | |
3344 | last_insn = insn; | |
3345 | continue; | |
3346 | ||
3347 | case NOTE: | |
3348 | switch (NOTE_KIND (insn)) | |
3349 | { | |
3350 | case NOTE_INSN_BLOCK_END: | |
3351 | gcc_unreachable (); | |
3352 | continue; | |
3353 | default: | |
3354 | continue; | |
3355 | break; | |
3356 | } | |
3357 | break; | |
3358 | ||
3359 | case CODE_LABEL: | |
3360 | if (NEXT_INSN (insn) | |
3361 | && JUMP_TABLE_DATA_P (NEXT_INSN (insn))) | |
3362 | { | |
3363 | insn = NEXT_INSN (insn); | |
3364 | last_insn = insn; | |
3365 | continue; | |
3366 | } | |
3367 | break; | |
3368 | ||
3369 | default: | |
3370 | break; | |
3371 | } | |
3372 | ||
3373 | break; | |
3374 | } | |
3375 | ||
3376 | /* It is possible to hit contradictory sequence. For instance: | |
3377 | ||
3378 | jump_insn | |
3379 | NOTE_INSN_BLOCK_BEG | |
3380 | barrier | |
3381 | ||
3382 | Where barrier belongs to jump_insn, but the note does not. This can be | |
3383 | created by removing the basic block originally following | |
3384 | NOTE_INSN_BLOCK_BEG. In such case reorder the notes. */ | |
3385 | ||
3386 | for (insn = last_insn; insn != BB_END (bb); insn = prev) | |
3387 | { | |
3388 | prev = PREV_INSN (insn); | |
3389 | if (NOTE_P (insn)) | |
3390 | switch (NOTE_KIND (insn)) | |
3391 | { | |
3392 | case NOTE_INSN_BLOCK_END: | |
3393 | gcc_unreachable (); | |
3394 | break; | |
3395 | case NOTE_INSN_DELETED: | |
3396 | case NOTE_INSN_DELETED_LABEL: | |
3397 | case NOTE_INSN_DELETED_DEBUG_LABEL: | |
3398 | continue; | |
3399 | default: | |
3400 | reorder_insns (insn, insn, last_insn); | |
3401 | } | |
3402 | } | |
3403 | ||
3404 | return last_insn; | |
3405 | } | |
3406 | ||
3407 | /* Locate or create a label for a given basic block. */ | |
3408 | ||
3409 | static rtx | |
3410 | label_for_bb (basic_block bb) | |
3411 | { | |
3412 | rtx label = BB_HEAD (bb); | |
3413 | ||
3414 | if (!LABEL_P (label)) | |
3415 | { | |
3416 | if (dump_file) | |
3417 | fprintf (dump_file, "Emitting label for block %d\n", bb->index); | |
3418 | ||
3419 | label = block_label (bb); | |
3420 | } | |
3421 | ||
3422 | return label; | |
3423 | } | |
3424 | ||
3425 | /* Locate the effective beginning and end of the insn chain for each | |
3426 | block, as defined by skip_insns_after_block above. */ | |
3427 | ||
3428 | static void | |
3429 | record_effective_endpoints (void) | |
3430 | { | |
3431 | rtx next_insn; | |
3432 | basic_block bb; | |
3433 | rtx insn; | |
3434 | ||
3435 | for (insn = get_insns (); | |
3436 | insn | |
3437 | && NOTE_P (insn) | |
3438 | && NOTE_KIND (insn) != NOTE_INSN_BASIC_BLOCK; | |
3439 | insn = NEXT_INSN (insn)) | |
3440 | continue; | |
3441 | /* No basic blocks at all? */ | |
3442 | gcc_assert (insn); | |
3443 | ||
3444 | if (PREV_INSN (insn)) | |
3445 | cfg_layout_function_header = | |
3446 | unlink_insn_chain (get_insns (), PREV_INSN (insn)); | |
3447 | else | |
3448 | cfg_layout_function_header = NULL_RTX; | |
3449 | ||
3450 | next_insn = get_insns (); | |
fc00614f | 3451 | FOR_EACH_BB_FN (bb, cfun) |
23a070f3 | 3452 | { |
3453 | rtx end; | |
3454 | ||
3455 | if (PREV_INSN (BB_HEAD (bb)) && next_insn != BB_HEAD (bb)) | |
3456 | BB_HEADER (bb) = unlink_insn_chain (next_insn, | |
3457 | PREV_INSN (BB_HEAD (bb))); | |
3458 | end = skip_insns_after_block (bb); | |
3459 | if (NEXT_INSN (BB_END (bb)) && BB_END (bb) != end) | |
3460 | BB_FOOTER (bb) = unlink_insn_chain (NEXT_INSN (BB_END (bb)), end); | |
3461 | next_insn = NEXT_INSN (BB_END (bb)); | |
3462 | } | |
3463 | ||
3464 | cfg_layout_function_footer = next_insn; | |
3465 | if (cfg_layout_function_footer) | |
3466 | cfg_layout_function_footer = unlink_insn_chain (cfg_layout_function_footer, get_last_insn ()); | |
3467 | } | |
3468 | \f | |
cbe8bda8 | 3469 | namespace { |
3470 | ||
3471 | const pass_data pass_data_into_cfg_layout_mode = | |
3472 | { | |
3473 | RTL_PASS, /* type */ | |
3474 | "into_cfglayout", /* name */ | |
3475 | OPTGROUP_NONE, /* optinfo_flags */ | |
cbe8bda8 | 3476 | true, /* has_execute */ |
3477 | TV_CFG, /* tv_id */ | |
3478 | 0, /* properties_required */ | |
3479 | PROP_cfglayout, /* properties_provided */ | |
3480 | 0, /* properties_destroyed */ | |
3481 | 0, /* todo_flags_start */ | |
3482 | 0, /* todo_flags_finish */ | |
23a070f3 | 3483 | }; |
3484 | ||
cbe8bda8 | 3485 | class pass_into_cfg_layout_mode : public rtl_opt_pass |
3486 | { | |
3487 | public: | |
9af5ce0c | 3488 | pass_into_cfg_layout_mode (gcc::context *ctxt) |
3489 | : rtl_opt_pass (pass_data_into_cfg_layout_mode, ctxt) | |
cbe8bda8 | 3490 | {} |
3491 | ||
3492 | /* opt_pass methods: */ | |
65b0537f | 3493 | virtual unsigned int execute (function *) |
3494 | { | |
3495 | cfg_layout_initialize (0); | |
3496 | return 0; | |
3497 | } | |
cbe8bda8 | 3498 | |
3499 | }; // class pass_into_cfg_layout_mode | |
3500 | ||
3501 | } // anon namespace | |
3502 | ||
3503 | rtl_opt_pass * | |
3504 | make_pass_into_cfg_layout_mode (gcc::context *ctxt) | |
3505 | { | |
3506 | return new pass_into_cfg_layout_mode (ctxt); | |
3507 | } | |
3508 | ||
3509 | namespace { | |
3510 | ||
3511 | const pass_data pass_data_outof_cfg_layout_mode = | |
3512 | { | |
3513 | RTL_PASS, /* type */ | |
3514 | "outof_cfglayout", /* name */ | |
3515 | OPTGROUP_NONE, /* optinfo_flags */ | |
cbe8bda8 | 3516 | true, /* has_execute */ |
3517 | TV_CFG, /* tv_id */ | |
3518 | 0, /* properties_required */ | |
3519 | 0, /* properties_provided */ | |
3520 | PROP_cfglayout, /* properties_destroyed */ | |
3521 | 0, /* todo_flags_start */ | |
3522 | 0, /* todo_flags_finish */ | |
23a070f3 | 3523 | }; |
cbe8bda8 | 3524 | |
3525 | class pass_outof_cfg_layout_mode : public rtl_opt_pass | |
3526 | { | |
3527 | public: | |
9af5ce0c | 3528 | pass_outof_cfg_layout_mode (gcc::context *ctxt) |
3529 | : rtl_opt_pass (pass_data_outof_cfg_layout_mode, ctxt) | |
cbe8bda8 | 3530 | {} |
3531 | ||
3532 | /* opt_pass methods: */ | |
65b0537f | 3533 | virtual unsigned int execute (function *); |
cbe8bda8 | 3534 | |
3535 | }; // class pass_outof_cfg_layout_mode | |
3536 | ||
65b0537f | 3537 | unsigned int |
3538 | pass_outof_cfg_layout_mode::execute (function *fun) | |
3539 | { | |
3540 | basic_block bb; | |
3541 | ||
3542 | FOR_EACH_BB_FN (bb, fun) | |
3543 | if (bb->next_bb != EXIT_BLOCK_PTR_FOR_FN (fun)) | |
3544 | bb->aux = bb->next_bb; | |
3545 | ||
3546 | cfg_layout_finalize (); | |
3547 | ||
3548 | return 0; | |
3549 | } | |
3550 | ||
cbe8bda8 | 3551 | } // anon namespace |
3552 | ||
3553 | rtl_opt_pass * | |
3554 | make_pass_outof_cfg_layout_mode (gcc::context *ctxt) | |
3555 | { | |
3556 | return new pass_outof_cfg_layout_mode (ctxt); | |
3557 | } | |
23a070f3 | 3558 | \f |
3559 | ||
3560 | /* Link the basic blocks in the correct order, compacting the basic | |
3561 | block queue while at it. If STAY_IN_CFGLAYOUT_MODE is false, this | |
3562 | function also clears the basic block header and footer fields. | |
3563 | ||
3564 | This function is usually called after a pass (e.g. tracer) finishes | |
3565 | some transformations while in cfglayout mode. The required sequence | |
3566 | of the basic blocks is in a linked list along the bb->aux field. | |
3567 | This functions re-links the basic block prev_bb and next_bb pointers | |
4a020a8c | 3568 | accordingly, and it compacts and renumbers the blocks. |
3569 | ||
3570 | FIXME: This currently works only for RTL, but the only RTL-specific | |
3571 | bits are the STAY_IN_CFGLAYOUT_MODE bits. The tracer pass was moved | |
3572 | to GIMPLE a long time ago, but it doesn't relink the basic block | |
3573 | chain. It could do that (to give better initial RTL) if this function | |
3574 | is made IR-agnostic (and moved to cfganal.c or cfg.c while at it). */ | |
23a070f3 | 3575 | |
3576 | void | |
3577 | relink_block_chain (bool stay_in_cfglayout_mode) | |
3578 | { | |
3579 | basic_block bb, prev_bb; | |
3580 | int index; | |
3581 | ||
3582 | /* Maybe dump the re-ordered sequence. */ | |
3583 | if (dump_file) | |
3584 | { | |
3585 | fprintf (dump_file, "Reordered sequence:\n"); | |
34154e27 | 3586 | for (bb = ENTRY_BLOCK_PTR_FOR_FN (cfun)->next_bb, index = |
3587 | NUM_FIXED_BLOCKS; | |
23a070f3 | 3588 | bb; |
3589 | bb = (basic_block) bb->aux, index++) | |
3590 | { | |
3591 | fprintf (dump_file, " %i ", index); | |
3592 | if (get_bb_original (bb)) | |
3593 | fprintf (dump_file, "duplicate of %i ", | |
3594 | get_bb_original (bb)->index); | |
3595 | else if (forwarder_block_p (bb) | |
3596 | && !LABEL_P (BB_HEAD (bb))) | |
3597 | fprintf (dump_file, "compensation "); | |
3598 | else | |
3599 | fprintf (dump_file, "bb %i ", bb->index); | |
3600 | fprintf (dump_file, " [%i]\n", bb->frequency); | |
3601 | } | |
3602 | } | |
3603 | ||
3604 | /* Now reorder the blocks. */ | |
34154e27 | 3605 | prev_bb = ENTRY_BLOCK_PTR_FOR_FN (cfun); |
3606 | bb = ENTRY_BLOCK_PTR_FOR_FN (cfun)->next_bb; | |
23a070f3 | 3607 | for (; bb; prev_bb = bb, bb = (basic_block) bb->aux) |
3608 | { | |
3609 | bb->prev_bb = prev_bb; | |
3610 | prev_bb->next_bb = bb; | |
3611 | } | |
34154e27 | 3612 | prev_bb->next_bb = EXIT_BLOCK_PTR_FOR_FN (cfun); |
3613 | EXIT_BLOCK_PTR_FOR_FN (cfun)->prev_bb = prev_bb; | |
23a070f3 | 3614 | |
3615 | /* Then, clean up the aux fields. */ | |
ed7d889a | 3616 | FOR_ALL_BB_FN (bb, cfun) |
23a070f3 | 3617 | { |
3618 | bb->aux = NULL; | |
3619 | if (!stay_in_cfglayout_mode) | |
3620 | BB_HEADER (bb) = BB_FOOTER (bb) = NULL; | |
3621 | } | |
3622 | ||
3623 | /* Maybe reset the original copy tables, they are not valid anymore | |
3624 | when we renumber the basic blocks in compact_blocks. If we are | |
3625 | are going out of cfglayout mode, don't re-allocate the tables. */ | |
3626 | free_original_copy_tables (); | |
3627 | if (stay_in_cfglayout_mode) | |
3628 | initialize_original_copy_tables (); | |
3629 | ||
3630 | /* Finally, put basic_block_info in the new order. */ | |
3631 | compact_blocks (); | |
3632 | } | |
3633 | \f | |
3634 | ||
3635 | /* Given a reorder chain, rearrange the code to match. */ | |
3636 | ||
3637 | static void | |
3638 | fixup_reorder_chain (void) | |
3639 | { | |
3640 | basic_block bb; | |
3641 | rtx insn = NULL; | |
3642 | ||
3643 | if (cfg_layout_function_header) | |
3644 | { | |
3645 | set_first_insn (cfg_layout_function_header); | |
3646 | insn = cfg_layout_function_header; | |
3647 | while (NEXT_INSN (insn)) | |
3648 | insn = NEXT_INSN (insn); | |
3649 | } | |
3650 | ||
3651 | /* First do the bulk reordering -- rechain the blocks without regard to | |
3652 | the needed changes to jumps and labels. */ | |
3653 | ||
34154e27 | 3654 | for (bb = ENTRY_BLOCK_PTR_FOR_FN (cfun)->next_bb; bb; bb = (basic_block) |
3655 | bb->aux) | |
23a070f3 | 3656 | { |
3657 | if (BB_HEADER (bb)) | |
3658 | { | |
3659 | if (insn) | |
3660 | NEXT_INSN (insn) = BB_HEADER (bb); | |
3661 | else | |
3662 | set_first_insn (BB_HEADER (bb)); | |
3663 | PREV_INSN (BB_HEADER (bb)) = insn; | |
3664 | insn = BB_HEADER (bb); | |
3665 | while (NEXT_INSN (insn)) | |
3666 | insn = NEXT_INSN (insn); | |
3667 | } | |
3668 | if (insn) | |
3669 | NEXT_INSN (insn) = BB_HEAD (bb); | |
3670 | else | |
3671 | set_first_insn (BB_HEAD (bb)); | |
3672 | PREV_INSN (BB_HEAD (bb)) = insn; | |
3673 | insn = BB_END (bb); | |
3674 | if (BB_FOOTER (bb)) | |
3675 | { | |
3676 | NEXT_INSN (insn) = BB_FOOTER (bb); | |
3677 | PREV_INSN (BB_FOOTER (bb)) = insn; | |
3678 | while (NEXT_INSN (insn)) | |
3679 | insn = NEXT_INSN (insn); | |
3680 | } | |
3681 | } | |
3682 | ||
3683 | NEXT_INSN (insn) = cfg_layout_function_footer; | |
3684 | if (cfg_layout_function_footer) | |
3685 | PREV_INSN (cfg_layout_function_footer) = insn; | |
3686 | ||
3687 | while (NEXT_INSN (insn)) | |
3688 | insn = NEXT_INSN (insn); | |
3689 | ||
3690 | set_last_insn (insn); | |
3691 | #ifdef ENABLE_CHECKING | |
3692 | verify_insn_chain (); | |
3693 | #endif | |
3694 | ||
3695 | /* Now add jumps and labels as needed to match the blocks new | |
c38b28e7 | 3696 | outgoing edges. */ |
23a070f3 | 3697 | |
c38b28e7 | 3698 | for (bb = ENTRY_BLOCK_PTR_FOR_FN (cfun)->next_bb; bb ; bb = (basic_block) |
3699 | bb->aux) | |
23a070f3 | 3700 | { |
3701 | edge e_fall, e_taken, e; | |
3702 | rtx bb_end_insn; | |
3703 | rtx ret_label = NULL_RTX; | |
aa78dca5 | 3704 | basic_block nb; |
23a070f3 | 3705 | edge_iterator ei; |
3706 | ||
3707 | if (EDGE_COUNT (bb->succs) == 0) | |
3708 | continue; | |
3709 | ||
3710 | /* Find the old fallthru edge, and another non-EH edge for | |
3711 | a taken jump. */ | |
3712 | e_taken = e_fall = NULL; | |
3713 | ||
3714 | FOR_EACH_EDGE (e, ei, bb->succs) | |
3715 | if (e->flags & EDGE_FALLTHRU) | |
3716 | e_fall = e; | |
3717 | else if (! (e->flags & EDGE_EH)) | |
3718 | e_taken = e; | |
3719 | ||
3720 | bb_end_insn = BB_END (bb); | |
3721 | if (JUMP_P (bb_end_insn)) | |
3722 | { | |
3723 | ret_label = JUMP_LABEL (bb_end_insn); | |
3724 | if (any_condjump_p (bb_end_insn)) | |
3725 | { | |
3726 | /* This might happen if the conditional jump has side | |
3727 | effects and could therefore not be optimized away. | |
3728 | Make the basic block to end with a barrier in order | |
3729 | to prevent rtl_verify_flow_info from complaining. */ | |
3730 | if (!e_fall) | |
3731 | { | |
3732 | gcc_assert (!onlyjump_p (bb_end_insn) | |
3b649e5d | 3733 | || returnjump_p (bb_end_insn) |
3734 | || (e_taken->flags & EDGE_CROSSING)); | |
91f71fa3 | 3735 | emit_barrier_after (bb_end_insn); |
23a070f3 | 3736 | continue; |
3737 | } | |
3738 | ||
3739 | /* If the old fallthru is still next, nothing to do. */ | |
3740 | if (bb->aux == e_fall->dest | |
34154e27 | 3741 | || e_fall->dest == EXIT_BLOCK_PTR_FOR_FN (cfun)) |
23a070f3 | 3742 | continue; |
3743 | ||
3744 | /* The degenerated case of conditional jump jumping to the next | |
3745 | instruction can happen for jumps with side effects. We need | |
3746 | to construct a forwarder block and this will be done just | |
3747 | fine by force_nonfallthru below. */ | |
3748 | if (!e_taken) | |
3749 | ; | |
3750 | ||
3751 | /* There is another special case: if *neither* block is next, | |
3752 | such as happens at the very end of a function, then we'll | |
3753 | need to add a new unconditional jump. Choose the taken | |
3754 | edge based on known or assumed probability. */ | |
3755 | else if (bb->aux != e_taken->dest) | |
3756 | { | |
3757 | rtx note = find_reg_note (bb_end_insn, REG_BR_PROB, 0); | |
3758 | ||
3759 | if (note | |
9eb946de | 3760 | && XINT (note, 0) < REG_BR_PROB_BASE / 2 |
23a070f3 | 3761 | && invert_jump (bb_end_insn, |
34154e27 | 3762 | (e_fall->dest |
3763 | == EXIT_BLOCK_PTR_FOR_FN (cfun) | |
23a070f3 | 3764 | ? NULL_RTX |
3765 | : label_for_bb (e_fall->dest)), 0)) | |
3766 | { | |
3767 | e_fall->flags &= ~EDGE_FALLTHRU; | |
3768 | gcc_checking_assert (could_fall_through | |
3769 | (e_taken->src, e_taken->dest)); | |
3770 | e_taken->flags |= EDGE_FALLTHRU; | |
3771 | update_br_prob_note (bb); | |
3772 | e = e_fall, e_fall = e_taken, e_taken = e; | |
3773 | } | |
3774 | } | |
3775 | ||
3776 | /* If the "jumping" edge is a crossing edge, and the fall | |
3777 | through edge is non-crossing, leave things as they are. */ | |
3778 | else if ((e_taken->flags & EDGE_CROSSING) | |
3779 | && !(e_fall->flags & EDGE_CROSSING)) | |
3780 | continue; | |
3781 | ||
3782 | /* Otherwise we can try to invert the jump. This will | |
3783 | basically never fail, however, keep up the pretense. */ | |
3784 | else if (invert_jump (bb_end_insn, | |
34154e27 | 3785 | (e_fall->dest |
3786 | == EXIT_BLOCK_PTR_FOR_FN (cfun) | |
23a070f3 | 3787 | ? NULL_RTX |
3788 | : label_for_bb (e_fall->dest)), 0)) | |
3789 | { | |
3790 | e_fall->flags &= ~EDGE_FALLTHRU; | |
3791 | gcc_checking_assert (could_fall_through | |
3792 | (e_taken->src, e_taken->dest)); | |
3793 | e_taken->flags |= EDGE_FALLTHRU; | |
3794 | update_br_prob_note (bb); | |
3795 | if (LABEL_NUSES (ret_label) == 0 | |
3796 | && single_pred_p (e_taken->dest)) | |
3797 | delete_insn (ret_label); | |
3798 | continue; | |
3799 | } | |
3800 | } | |
3801 | else if (extract_asm_operands (PATTERN (bb_end_insn)) != NULL) | |
3802 | { | |
3803 | /* If the old fallthru is still next or if | |
3804 | asm goto doesn't have a fallthru (e.g. when followed by | |
3805 | __builtin_unreachable ()), nothing to do. */ | |
3806 | if (! e_fall | |
3807 | || bb->aux == e_fall->dest | |
34154e27 | 3808 | || e_fall->dest == EXIT_BLOCK_PTR_FOR_FN (cfun)) |
23a070f3 | 3809 | continue; |
3810 | ||
3811 | /* Otherwise we'll have to use the fallthru fixup below. */ | |
3812 | } | |
3813 | else | |
3814 | { | |
3815 | /* Otherwise we have some return, switch or computed | |
3816 | jump. In the 99% case, there should not have been a | |
3817 | fallthru edge. */ | |
3818 | gcc_assert (returnjump_p (bb_end_insn) || !e_fall); | |
3819 | continue; | |
3820 | } | |
3821 | } | |
3822 | else | |
3823 | { | |
3824 | /* No fallthru implies a noreturn function with EH edges, or | |
3825 | something similarly bizarre. In any case, we don't need to | |
3826 | do anything. */ | |
3827 | if (! e_fall) | |
3828 | continue; | |
3829 | ||
3830 | /* If the fallthru block is still next, nothing to do. */ | |
3831 | if (bb->aux == e_fall->dest) | |
3832 | continue; | |
3833 | ||
3834 | /* A fallthru to exit block. */ | |
34154e27 | 3835 | if (e_fall->dest == EXIT_BLOCK_PTR_FOR_FN (cfun)) |
23a070f3 | 3836 | continue; |
3837 | } | |
3838 | ||
3839 | /* We got here if we need to add a new jump insn. | |
3840 | Note force_nonfallthru can delete E_FALL and thus we have to | |
3841 | save E_FALL->src prior to the call to force_nonfallthru. */ | |
23a070f3 | 3842 | nb = force_nonfallthru_and_redirect (e_fall, e_fall->dest, ret_label); |
3843 | if (nb) | |
3844 | { | |
3845 | nb->aux = bb->aux; | |
3846 | bb->aux = nb; | |
3847 | /* Don't process this new block. */ | |
3848 | bb = nb; | |
23a070f3 | 3849 | } |
3850 | } | |
3851 | ||
3852 | relink_block_chain (/*stay_in_cfglayout_mode=*/false); | |
3853 | ||
c38b28e7 | 3854 | /* Annoying special case - jump around dead jumptables left in the code. */ |
fc00614f | 3855 | FOR_EACH_BB_FN (bb, cfun) |
23a070f3 | 3856 | { |
3857 | edge e = find_fallthru_edge (bb->succs); | |
3858 | ||
c38b28e7 | 3859 | if (e && !can_fallthru (e->src, e->dest)) |
3860 | force_nonfallthru (e); | |
23a070f3 | 3861 | } |
3862 | ||
3863 | /* Ensure goto_locus from edges has some instructions with that locus | |
3864 | in RTL. */ | |
3865 | if (!optimize) | |
fc00614f | 3866 | FOR_EACH_BB_FN (bb, cfun) |
23a070f3 | 3867 | { |
3868 | edge e; | |
3869 | edge_iterator ei; | |
3870 | ||
3871 | FOR_EACH_EDGE (e, ei, bb->succs) | |
8e7408e3 | 3872 | if (LOCATION_LOCUS (e->goto_locus) != UNKNOWN_LOCATION |
5169661d | 3873 | && !(e->flags & EDGE_ABNORMAL)) |
23a070f3 | 3874 | { |
3875 | edge e2; | |
3876 | edge_iterator ei2; | |
3877 | basic_block dest, nb; | |
3878 | rtx end; | |
3879 | ||
3880 | insn = BB_END (e->src); | |
3881 | end = PREV_INSN (BB_HEAD (e->src)); | |
3882 | while (insn != end | |
5169661d | 3883 | && (!NONDEBUG_INSN_P (insn) || !INSN_HAS_LOCATION (insn))) |
23a070f3 | 3884 | insn = PREV_INSN (insn); |
3885 | if (insn != end | |
5169661d | 3886 | && INSN_LOCATION (insn) == e->goto_locus) |
23a070f3 | 3887 | continue; |
3888 | if (simplejump_p (BB_END (e->src)) | |
5169661d | 3889 | && !INSN_HAS_LOCATION (BB_END (e->src))) |
23a070f3 | 3890 | { |
5169661d | 3891 | INSN_LOCATION (BB_END (e->src)) = e->goto_locus; |
23a070f3 | 3892 | continue; |
3893 | } | |
3894 | dest = e->dest; | |
34154e27 | 3895 | if (dest == EXIT_BLOCK_PTR_FOR_FN (cfun)) |
23a070f3 | 3896 | { |
3897 | /* Non-fallthru edges to the exit block cannot be split. */ | |
3898 | if (!(e->flags & EDGE_FALLTHRU)) | |
3899 | continue; | |
3900 | } | |
3901 | else | |
3902 | { | |
3903 | insn = BB_HEAD (dest); | |
3904 | end = NEXT_INSN (BB_END (dest)); | |
3905 | while (insn != end && !NONDEBUG_INSN_P (insn)) | |
3906 | insn = NEXT_INSN (insn); | |
5169661d | 3907 | if (insn != end && INSN_HAS_LOCATION (insn) |
3908 | && INSN_LOCATION (insn) == e->goto_locus) | |
23a070f3 | 3909 | continue; |
3910 | } | |
3911 | nb = split_edge (e); | |
3912 | if (!INSN_P (BB_END (nb))) | |
3913 | BB_END (nb) = emit_insn_after_noloc (gen_nop (), BB_END (nb), | |
3914 | nb); | |
5169661d | 3915 | INSN_LOCATION (BB_END (nb)) = e->goto_locus; |
23a070f3 | 3916 | |
3917 | /* If there are other incoming edges to the destination block | |
3918 | with the same goto locus, redirect them to the new block as | |
3919 | well, this can prevent other such blocks from being created | |
3920 | in subsequent iterations of the loop. */ | |
3921 | for (ei2 = ei_start (dest->preds); (e2 = ei_safe_edge (ei2)); ) | |
8e7408e3 | 3922 | if (LOCATION_LOCUS (e2->goto_locus) != UNKNOWN_LOCATION |
23a070f3 | 3923 | && !(e2->flags & (EDGE_ABNORMAL | EDGE_FALLTHRU)) |
5169661d | 3924 | && e->goto_locus == e2->goto_locus) |
23a070f3 | 3925 | redirect_edge_and_branch (e2, nb); |
3926 | else | |
3927 | ei_next (&ei2); | |
3928 | } | |
3929 | } | |
3930 | } | |
3931 | \f | |
3932 | /* Perform sanity checks on the insn chain. | |
3933 | 1. Check that next/prev pointers are consistent in both the forward and | |
3934 | reverse direction. | |
3935 | 2. Count insns in chain, going both directions, and check if equal. | |
3936 | 3. Check that get_last_insn () returns the actual end of chain. */ | |
3937 | ||
3938 | DEBUG_FUNCTION void | |
3939 | verify_insn_chain (void) | |
3940 | { | |
3941 | rtx x, prevx, nextx; | |
3942 | int insn_cnt1, insn_cnt2; | |
3943 | ||
3944 | for (prevx = NULL, insn_cnt1 = 1, x = get_insns (); | |
3945 | x != 0; | |
3946 | prevx = x, insn_cnt1++, x = NEXT_INSN (x)) | |
3947 | gcc_assert (PREV_INSN (x) == prevx); | |
3948 | ||
3949 | gcc_assert (prevx == get_last_insn ()); | |
3950 | ||
3951 | for (nextx = NULL, insn_cnt2 = 1, x = get_last_insn (); | |
3952 | x != 0; | |
3953 | nextx = x, insn_cnt2++, x = PREV_INSN (x)) | |
3954 | gcc_assert (NEXT_INSN (x) == nextx); | |
3955 | ||
3956 | gcc_assert (insn_cnt1 == insn_cnt2); | |
3957 | } | |
3958 | \f | |
3959 | /* If we have assembler epilogues, the block falling through to exit must | |
3960 | be the last one in the reordered chain when we reach final. Ensure | |
3961 | that this condition is met. */ | |
3962 | static void | |
3963 | fixup_fallthru_exit_predecessor (void) | |
3964 | { | |
3965 | edge e; | |
3966 | basic_block bb = NULL; | |
3967 | ||
3968 | /* This transformation is not valid before reload, because we might | |
3969 | separate a call from the instruction that copies the return | |
3970 | value. */ | |
3971 | gcc_assert (reload_completed); | |
3972 | ||
34154e27 | 3973 | e = find_fallthru_edge (EXIT_BLOCK_PTR_FOR_FN (cfun)->preds); |
23a070f3 | 3974 | if (e) |
3975 | bb = e->src; | |
3976 | ||
3977 | if (bb && bb->aux) | |
3978 | { | |
34154e27 | 3979 | basic_block c = ENTRY_BLOCK_PTR_FOR_FN (cfun)->next_bb; |
23a070f3 | 3980 | |
3981 | /* If the very first block is the one with the fall-through exit | |
3982 | edge, we have to split that block. */ | |
3983 | if (c == bb) | |
3984 | { | |
3985 | bb = split_block (bb, NULL)->dest; | |
3986 | bb->aux = c->aux; | |
3987 | c->aux = bb; | |
3988 | BB_FOOTER (bb) = BB_FOOTER (c); | |
3989 | BB_FOOTER (c) = NULL; | |
3990 | } | |
3991 | ||
3992 | while (c->aux != bb) | |
3993 | c = (basic_block) c->aux; | |
3994 | ||
3995 | c->aux = bb->aux; | |
3996 | while (c->aux) | |
3997 | c = (basic_block) c->aux; | |
3998 | ||
3999 | c->aux = bb; | |
4000 | bb->aux = NULL; | |
4001 | } | |
4002 | } | |
4003 | ||
4004 | /* In case there are more than one fallthru predecessors of exit, force that | |
4005 | there is only one. */ | |
4006 | ||
4007 | static void | |
4008 | force_one_exit_fallthru (void) | |
4009 | { | |
4010 | edge e, predecessor = NULL; | |
4011 | bool more = false; | |
4012 | edge_iterator ei; | |
4013 | basic_block forwarder, bb; | |
4014 | ||
34154e27 | 4015 | FOR_EACH_EDGE (e, ei, EXIT_BLOCK_PTR_FOR_FN (cfun)->preds) |
23a070f3 | 4016 | if (e->flags & EDGE_FALLTHRU) |
4017 | { | |
4018 | if (predecessor == NULL) | |
4019 | predecessor = e; | |
4020 | else | |
4021 | { | |
4022 | more = true; | |
4023 | break; | |
4024 | } | |
4025 | } | |
4026 | ||
4027 | if (!more) | |
4028 | return; | |
4029 | ||
4030 | /* Exit has several fallthru predecessors. Create a forwarder block for | |
4031 | them. */ | |
4032 | forwarder = split_edge (predecessor); | |
34154e27 | 4033 | for (ei = ei_start (EXIT_BLOCK_PTR_FOR_FN (cfun)->preds); |
4034 | (e = ei_safe_edge (ei)); ) | |
23a070f3 | 4035 | { |
4036 | if (e->src == forwarder | |
4037 | || !(e->flags & EDGE_FALLTHRU)) | |
4038 | ei_next (&ei); | |
4039 | else | |
4040 | redirect_edge_and_branch_force (e, forwarder); | |
4041 | } | |
4042 | ||
4043 | /* Fix up the chain of blocks -- make FORWARDER immediately precede the | |
4044 | exit block. */ | |
fc00614f | 4045 | FOR_EACH_BB_FN (bb, cfun) |
23a070f3 | 4046 | { |
4047 | if (bb->aux == NULL && bb != forwarder) | |
4048 | { | |
4049 | bb->aux = forwarder; | |
4050 | break; | |
4051 | } | |
4052 | } | |
4053 | } | |
4054 | \f | |
4055 | /* Return true in case it is possible to duplicate the basic block BB. */ | |
4056 | ||
4057 | static bool | |
4058 | cfg_layout_can_duplicate_bb_p (const_basic_block bb) | |
4059 | { | |
4060 | /* Do not attempt to duplicate tablejumps, as we need to unshare | |
4061 | the dispatch table. This is difficult to do, as the instructions | |
4062 | computing jump destination may be hoisted outside the basic block. */ | |
4063 | if (tablejump_p (BB_END (bb), NULL, NULL)) | |
4064 | return false; | |
4065 | ||
4066 | /* Do not duplicate blocks containing insns that can't be copied. */ | |
4067 | if (targetm.cannot_copy_insn_p) | |
4068 | { | |
4069 | rtx insn = BB_HEAD (bb); | |
4070 | while (1) | |
4071 | { | |
4072 | if (INSN_P (insn) && targetm.cannot_copy_insn_p (insn)) | |
4073 | return false; | |
4074 | if (insn == BB_END (bb)) | |
4075 | break; | |
4076 | insn = NEXT_INSN (insn); | |
4077 | } | |
4078 | } | |
4079 | ||
4080 | return true; | |
4081 | } | |
4082 | ||
4083 | rtx | |
4084 | duplicate_insn_chain (rtx from, rtx to) | |
4085 | { | |
91f71fa3 | 4086 | rtx insn, next, last, copy; |
23a070f3 | 4087 | |
4088 | /* Avoid updating of boundaries of previous basic block. The | |
4089 | note will get removed from insn stream in fixup. */ | |
4090 | last = emit_note (NOTE_INSN_DELETED); | |
4091 | ||
4092 | /* Create copy at the end of INSN chain. The chain will | |
4093 | be reordered later. */ | |
4094 | for (insn = from; insn != NEXT_INSN (to); insn = NEXT_INSN (insn)) | |
4095 | { | |
4096 | switch (GET_CODE (insn)) | |
4097 | { | |
4098 | case DEBUG_INSN: | |
4099 | /* Don't duplicate label debug insns. */ | |
4100 | if (TREE_CODE (INSN_VAR_LOCATION_DECL (insn)) == LABEL_DECL) | |
4101 | break; | |
4102 | /* FALLTHRU */ | |
4103 | case INSN: | |
4104 | case CALL_INSN: | |
4105 | case JUMP_INSN: | |
23a070f3 | 4106 | copy = emit_copy_of_insn_after (insn, get_last_insn ()); |
4107 | if (JUMP_P (insn) && JUMP_LABEL (insn) != NULL_RTX | |
4108 | && ANY_RETURN_P (JUMP_LABEL (insn))) | |
4109 | JUMP_LABEL (copy) = JUMP_LABEL (insn); | |
4110 | maybe_copy_prologue_epilogue_insn (insn, copy); | |
4111 | break; | |
4112 | ||
91f71fa3 | 4113 | case JUMP_TABLE_DATA: |
4114 | /* Avoid copying of dispatch tables. We never duplicate | |
4115 | tablejumps, so this can hit only in case the table got | |
4116 | moved far from original jump. | |
4117 | Avoid copying following barrier as well if any | |
4118 | (and debug insns in between). */ | |
4119 | for (next = NEXT_INSN (insn); | |
4120 | next != NEXT_INSN (to); | |
4121 | next = NEXT_INSN (next)) | |
4122 | if (!DEBUG_INSN_P (next)) | |
4123 | break; | |
4124 | if (next != NEXT_INSN (to) && BARRIER_P (next)) | |
4125 | insn = next; | |
4126 | break; | |
4127 | ||
23a070f3 | 4128 | case CODE_LABEL: |
4129 | break; | |
4130 | ||
4131 | case BARRIER: | |
4132 | emit_barrier (); | |
4133 | break; | |
4134 | ||
4135 | case NOTE: | |
4136 | switch (NOTE_KIND (insn)) | |
4137 | { | |
4138 | /* In case prologue is empty and function contain label | |
4139 | in first BB, we may want to copy the block. */ | |
4140 | case NOTE_INSN_PROLOGUE_END: | |
4141 | ||
4142 | case NOTE_INSN_DELETED: | |
4143 | case NOTE_INSN_DELETED_LABEL: | |
4144 | case NOTE_INSN_DELETED_DEBUG_LABEL: | |
4145 | /* No problem to strip these. */ | |
4146 | case NOTE_INSN_FUNCTION_BEG: | |
4147 | /* There is always just single entry to function. */ | |
4148 | case NOTE_INSN_BASIC_BLOCK: | |
aa78dca5 | 4149 | /* We should only switch text sections once. */ |
4150 | case NOTE_INSN_SWITCH_TEXT_SECTIONS: | |
23a070f3 | 4151 | break; |
4152 | ||
4153 | case NOTE_INSN_EPILOGUE_BEG: | |
23a070f3 | 4154 | emit_note_copy (insn); |
4155 | break; | |
4156 | ||
4157 | default: | |
4158 | /* All other notes should have already been eliminated. */ | |
4159 | gcc_unreachable (); | |
4160 | } | |
4161 | break; | |
4162 | default: | |
4163 | gcc_unreachable (); | |
4164 | } | |
4165 | } | |
4166 | insn = NEXT_INSN (last); | |
4167 | delete_insn (last); | |
4168 | return insn; | |
4169 | } | |
4170 | ||
4171 | /* Create a duplicate of the basic block BB. */ | |
4172 | ||
4173 | static basic_block | |
4174 | cfg_layout_duplicate_bb (basic_block bb) | |
4175 | { | |
4176 | rtx insn; | |
4177 | basic_block new_bb; | |
4178 | ||
4179 | insn = duplicate_insn_chain (BB_HEAD (bb), BB_END (bb)); | |
4180 | new_bb = create_basic_block (insn, | |
4181 | insn ? get_last_insn () : NULL, | |
34154e27 | 4182 | EXIT_BLOCK_PTR_FOR_FN (cfun)->prev_bb); |
23a070f3 | 4183 | |
4184 | BB_COPY_PARTITION (new_bb, bb); | |
4185 | if (BB_HEADER (bb)) | |
4186 | { | |
4187 | insn = BB_HEADER (bb); | |
4188 | while (NEXT_INSN (insn)) | |
4189 | insn = NEXT_INSN (insn); | |
4190 | insn = duplicate_insn_chain (BB_HEADER (bb), insn); | |
4191 | if (insn) | |
4192 | BB_HEADER (new_bb) = unlink_insn_chain (insn, get_last_insn ()); | |
4193 | } | |
4194 | ||
4195 | if (BB_FOOTER (bb)) | |
4196 | { | |
4197 | insn = BB_FOOTER (bb); | |
4198 | while (NEXT_INSN (insn)) | |
4199 | insn = NEXT_INSN (insn); | |
4200 | insn = duplicate_insn_chain (BB_FOOTER (bb), insn); | |
4201 | if (insn) | |
4202 | BB_FOOTER (new_bb) = unlink_insn_chain (insn, get_last_insn ()); | |
4203 | } | |
4204 | ||
4205 | return new_bb; | |
4206 | } | |
4207 | ||
4208 | \f | |
4209 | /* Main entry point to this module - initialize the datastructures for | |
4210 | CFG layout changes. It keeps LOOPS up-to-date if not null. | |
4211 | ||
4212 | FLAGS is a set of additional flags to pass to cleanup_cfg(). */ | |
4213 | ||
4214 | void | |
4215 | cfg_layout_initialize (unsigned int flags) | |
4216 | { | |
4217 | rtx x; | |
4218 | basic_block bb; | |
4219 | ||
e31c70b9 | 4220 | /* Once bb reordering is complete, cfg layout mode should not be re-entered. |
4221 | Entering cfg layout mode will perform optimizations on the cfg that | |
4222 | could affect the bb layout negatively or even require fixups. An | |
4223 | example of the latter is if edge forwarding performed when optimizing | |
4224 | the cfg layout required moving a block from the hot to the cold section | |
4225 | under -freorder-blocks-and-partition. This would create an illegal | |
4226 | partitioning unless some manual fixup was performed. */ | |
4227 | gcc_assert (!crtl->bb_reorder_complete); | |
4228 | ||
23a070f3 | 4229 | initialize_original_copy_tables (); |
4230 | ||
4231 | cfg_layout_rtl_register_cfg_hooks (); | |
4232 | ||
4233 | record_effective_endpoints (); | |
4234 | ||
4235 | /* Make sure that the targets of non local gotos are marked. */ | |
4236 | for (x = nonlocal_goto_handler_labels; x; x = XEXP (x, 1)) | |
4237 | { | |
4238 | bb = BLOCK_FOR_INSN (XEXP (x, 0)); | |
4239 | bb->flags |= BB_NON_LOCAL_GOTO_TARGET; | |
4240 | } | |
4241 | ||
4242 | cleanup_cfg (CLEANUP_CFGLAYOUT | flags); | |
4243 | } | |
4244 | ||
4245 | /* Splits superblocks. */ | |
4246 | void | |
4247 | break_superblocks (void) | |
4248 | { | |
4249 | sbitmap superblocks; | |
4250 | bool need = false; | |
4251 | basic_block bb; | |
4252 | ||
fe672ac0 | 4253 | superblocks = sbitmap_alloc (last_basic_block_for_fn (cfun)); |
53c5d9d4 | 4254 | bitmap_clear (superblocks); |
23a070f3 | 4255 | |
fc00614f | 4256 | FOR_EACH_BB_FN (bb, cfun) |
23a070f3 | 4257 | if (bb->flags & BB_SUPERBLOCK) |
4258 | { | |
4259 | bb->flags &= ~BB_SUPERBLOCK; | |
08b7917c | 4260 | bitmap_set_bit (superblocks, bb->index); |
23a070f3 | 4261 | need = true; |
4262 | } | |
4263 | ||
4264 | if (need) | |
4265 | { | |
4266 | rebuild_jump_labels (get_insns ()); | |
4267 | find_many_sub_basic_blocks (superblocks); | |
4268 | } | |
4269 | ||
4270 | free (superblocks); | |
4271 | } | |
4272 | ||
4273 | /* Finalize the changes: reorder insn list according to the sequence specified | |
c38b28e7 | 4274 | by aux pointers, enter compensation code, rebuild scope forest. */ |
23a070f3 | 4275 | |
4276 | void | |
4277 | cfg_layout_finalize (void) | |
4278 | { | |
4279 | #ifdef ENABLE_CHECKING | |
4280 | verify_flow_info (); | |
4281 | #endif | |
4282 | force_one_exit_fallthru (); | |
4283 | rtl_register_cfg_hooks (); | |
4284 | if (reload_completed | |
4285 | #ifdef HAVE_epilogue | |
4286 | && !HAVE_epilogue | |
4287 | #endif | |
4288 | ) | |
4289 | fixup_fallthru_exit_predecessor (); | |
4290 | fixup_reorder_chain (); | |
4291 | ||
c38b28e7 | 4292 | rebuild_jump_labels (get_insns ()); |
4293 | delete_dead_jumptables (); | |
4294 | ||
23a070f3 | 4295 | #ifdef ENABLE_CHECKING |
4296 | verify_insn_chain (); | |
4297 | verify_flow_info (); | |
4298 | #endif | |
4299 | } | |
4300 | ||
54f21e20 | 4301 | |
1026363d | 4302 | /* Same as split_block but update cfg_layout structures. */ |
5f5d4cd1 | 4303 | |
4304 | static basic_block | |
4c9e08a4 | 4305 | cfg_layout_split_block (basic_block bb, void *insnp) |
1026363d | 4306 | { |
f780cc25 | 4307 | rtx insn = (rtx) insnp; |
5f5d4cd1 | 4308 | basic_block new_bb = rtl_split_block (bb, insn); |
1026363d | 4309 | |
43e94e51 | 4310 | BB_FOOTER (new_bb) = BB_FOOTER (bb); |
4311 | BB_FOOTER (bb) = NULL; | |
1026363d | 4312 | |
5f5d4cd1 | 4313 | return new_bb; |
1026363d | 4314 | } |
4315 | ||
1026363d | 4316 | /* Redirect Edge to DEST. */ |
4ee9c684 | 4317 | static edge |
4c9e08a4 | 4318 | cfg_layout_redirect_edge_and_branch (edge e, basic_block dest) |
1026363d | 4319 | { |
4320 | basic_block src = e->src; | |
4ee9c684 | 4321 | edge ret; |
1026363d | 4322 | |
c60fa3a7 | 4323 | if (e->flags & (EDGE_ABNORMAL_CALL | EDGE_EH)) |
4ee9c684 | 4324 | return NULL; |
c60fa3a7 | 4325 | |
e5562ab8 | 4326 | if (e->dest == dest) |
4ee9c684 | 4327 | return e; |
c60fa3a7 | 4328 | |
34154e27 | 4329 | if (e->src != ENTRY_BLOCK_PTR_FOR_FN (cfun) |
4ee9c684 | 4330 | && (ret = try_redirect_by_replacing_jump (e, dest, true))) |
adee86a0 | 4331 | { |
3072d30e | 4332 | df_set_bb_dirty (src); |
4ee9c684 | 4333 | return ret; |
adee86a0 | 4334 | } |
c60fa3a7 | 4335 | |
34154e27 | 4336 | if (e->src == ENTRY_BLOCK_PTR_FOR_FN (cfun) |
c60fa3a7 | 4337 | && (e->flags & EDGE_FALLTHRU) && !(e->flags & EDGE_COMPLEX)) |
4338 | { | |
450d042a | 4339 | if (dump_file) |
4340 | fprintf (dump_file, "Redirecting entry edge from bb %i to %i\n", | |
c60fa3a7 | 4341 | e->src->index, dest->index); |
4342 | ||
3072d30e | 4343 | df_set_bb_dirty (e->src); |
c60fa3a7 | 4344 | redirect_edge_succ (e, dest); |
4ee9c684 | 4345 | return e; |
c60fa3a7 | 4346 | } |
4347 | ||
1026363d | 4348 | /* Redirect_edge_and_branch may decide to turn branch into fallthru edge |
4349 | in the case the basic block appears to be in sequence. Avoid this | |
4350 | transformation. */ | |
4351 | ||
1026363d | 4352 | if (e->flags & EDGE_FALLTHRU) |
4353 | { | |
4354 | /* Redirect any branch edges unified with the fallthru one. */ | |
6d7dc5b9 | 4355 | if (JUMP_P (BB_END (src)) |
b9de5542 | 4356 | && label_is_jump_target_p (BB_HEAD (e->dest), |
4357 | BB_END (src))) | |
1026363d | 4358 | { |
cc636d56 | 4359 | edge redirected; |
a0c938f0 | 4360 | |
450d042a | 4361 | if (dump_file) |
4362 | fprintf (dump_file, "Fallthru edge unified with branch " | |
b9de5542 | 4363 | "%i->%i redirected to %i\n", |
4364 | e->src->index, e->dest->index, dest->index); | |
4365 | e->flags &= ~EDGE_FALLTHRU; | |
cc636d56 | 4366 | redirected = redirect_branch_edge (e, dest); |
4367 | gcc_assert (redirected); | |
d5321455 | 4368 | redirected->flags |= EDGE_FALLTHRU; |
4369 | df_set_bb_dirty (redirected->src); | |
4370 | return redirected; | |
1026363d | 4371 | } |
4372 | /* In case we are redirecting fallthru edge to the branch edge | |
a0c938f0 | 4373 | of conditional jump, remove it. */ |
cd665a06 | 4374 | if (EDGE_COUNT (src->succs) == 2) |
1026363d | 4375 | { |
9ea57afb | 4376 | /* Find the edge that is different from E. */ |
4377 | edge s = EDGE_SUCC (src, EDGE_SUCC (src, 0) == e); | |
cd665a06 | 4378 | |
1026363d | 4379 | if (s->dest == dest |
5496dbfc | 4380 | && any_condjump_p (BB_END (src)) |
4381 | && onlyjump_p (BB_END (src))) | |
4382 | delete_insn (BB_END (src)); | |
1026363d | 4383 | } |
450d042a | 4384 | if (dump_file) |
6d31b223 | 4385 | fprintf (dump_file, "Redirecting fallthru edge %i->%i to %i\n", |
c60fa3a7 | 4386 | e->src->index, e->dest->index, dest->index); |
d5321455 | 4387 | ret = redirect_edge_succ_nodup (e, dest); |
1026363d | 4388 | } |
4389 | else | |
c60fa3a7 | 4390 | ret = redirect_branch_edge (e, dest); |
1026363d | 4391 | |
4392 | /* We don't want simplejumps in the insn stream during cfglayout. */ | |
cc636d56 | 4393 | gcc_assert (!simplejump_p (BB_END (src))); |
1026363d | 4394 | |
3072d30e | 4395 | df_set_bb_dirty (src); |
1026363d | 4396 | return ret; |
4397 | } | |
4398 | ||
4399 | /* Simple wrapper as we always can redirect fallthru edges. */ | |
4400 | static basic_block | |
4c9e08a4 | 4401 | cfg_layout_redirect_edge_and_branch_force (edge e, basic_block dest) |
1026363d | 4402 | { |
cc636d56 | 4403 | edge redirected = cfg_layout_redirect_edge_and_branch (e, dest); |
4404 | ||
4405 | gcc_assert (redirected); | |
1026363d | 4406 | return NULL; |
4407 | } | |
4408 | ||
5f5d4cd1 | 4409 | /* Same as delete_basic_block but update cfg_layout structures. */ |
4410 | ||
1026363d | 4411 | static void |
4c9e08a4 | 4412 | cfg_layout_delete_block (basic_block bb) |
1026363d | 4413 | { |
5496dbfc | 4414 | rtx insn, next, prev = PREV_INSN (BB_HEAD (bb)), *to, remaints; |
1026363d | 4415 | |
43e94e51 | 4416 | if (BB_HEADER (bb)) |
1026363d | 4417 | { |
5496dbfc | 4418 | next = BB_HEAD (bb); |
1026363d | 4419 | if (prev) |
43e94e51 | 4420 | NEXT_INSN (prev) = BB_HEADER (bb); |
1026363d | 4421 | else |
43e94e51 | 4422 | set_first_insn (BB_HEADER (bb)); |
4423 | PREV_INSN (BB_HEADER (bb)) = prev; | |
4424 | insn = BB_HEADER (bb); | |
1026363d | 4425 | while (NEXT_INSN (insn)) |
4426 | insn = NEXT_INSN (insn); | |
4427 | NEXT_INSN (insn) = next; | |
4428 | PREV_INSN (next) = insn; | |
4429 | } | |
5496dbfc | 4430 | next = NEXT_INSN (BB_END (bb)); |
43e94e51 | 4431 | if (BB_FOOTER (bb)) |
1026363d | 4432 | { |
43e94e51 | 4433 | insn = BB_FOOTER (bb); |
c60fa3a7 | 4434 | while (insn) |
4435 | { | |
6d7dc5b9 | 4436 | if (BARRIER_P (insn)) |
c60fa3a7 | 4437 | { |
4438 | if (PREV_INSN (insn)) | |
4439 | NEXT_INSN (PREV_INSN (insn)) = NEXT_INSN (insn); | |
4440 | else | |
43e94e51 | 4441 | BB_FOOTER (bb) = NEXT_INSN (insn); |
c60fa3a7 | 4442 | if (NEXT_INSN (insn)) |
4443 | PREV_INSN (NEXT_INSN (insn)) = PREV_INSN (insn); | |
4444 | } | |
6d7dc5b9 | 4445 | if (LABEL_P (insn)) |
c60fa3a7 | 4446 | break; |
4447 | insn = NEXT_INSN (insn); | |
4448 | } | |
43e94e51 | 4449 | if (BB_FOOTER (bb)) |
c60fa3a7 | 4450 | { |
5496dbfc | 4451 | insn = BB_END (bb); |
43e94e51 | 4452 | NEXT_INSN (insn) = BB_FOOTER (bb); |
4453 | PREV_INSN (BB_FOOTER (bb)) = insn; | |
c60fa3a7 | 4454 | while (NEXT_INSN (insn)) |
4455 | insn = NEXT_INSN (insn); | |
4456 | NEXT_INSN (insn) = next; | |
4457 | if (next) | |
4458 | PREV_INSN (next) = insn; | |
4459 | else | |
4460 | set_last_insn (insn); | |
4461 | } | |
1026363d | 4462 | } |
34154e27 | 4463 | if (bb->next_bb != EXIT_BLOCK_PTR_FOR_FN (cfun)) |
43e94e51 | 4464 | to = &BB_HEADER (bb->next_bb); |
1026363d | 4465 | else |
4466 | to = &cfg_layout_function_footer; | |
7a22afab | 4467 | |
1026363d | 4468 | rtl_delete_block (bb); |
4469 | ||
4470 | if (prev) | |
4471 | prev = NEXT_INSN (prev); | |
4c9e08a4 | 4472 | else |
1026363d | 4473 | prev = get_insns (); |
4474 | if (next) | |
4475 | next = PREV_INSN (next); | |
4c9e08a4 | 4476 | else |
1026363d | 4477 | next = get_last_insn (); |
4478 | ||
4479 | if (next && NEXT_INSN (next) != prev) | |
4480 | { | |
4481 | remaints = unlink_insn_chain (prev, next); | |
4482 | insn = remaints; | |
4483 | while (NEXT_INSN (insn)) | |
4484 | insn = NEXT_INSN (insn); | |
4485 | NEXT_INSN (insn) = *to; | |
4486 | if (*to) | |
4487 | PREV_INSN (*to) = insn; | |
4488 | *to = remaints; | |
4489 | } | |
4490 | } | |
4491 | ||
139c3f48 | 4492 | /* Return true when blocks A and B can be safely merged. */ |
47aaf6e6 | 4493 | |
c60fa3a7 | 4494 | static bool |
47aaf6e6 | 4495 | cfg_layout_can_merge_blocks_p (basic_block a, basic_block b) |
c60fa3a7 | 4496 | { |
4f18499c | 4497 | /* If we are partitioning hot/cold basic blocks, we don't want to |
4498 | mess up unconditional or indirect jumps that cross between hot | |
7562ed74 | 4499 | and cold sections. |
4500 | ||
1118aef7 | 4501 | Basic block partitioning may result in some jumps that appear to |
a0c938f0 | 4502 | be optimizable (or blocks that appear to be mergeable), but which really |
4503 | must be left untouched (they are required to make it safely across | |
4504 | partition boundaries). See the comments at the top of | |
1118aef7 | 4505 | bb-reorder.c:partition_hot_cold_basic_blocks for complete details. */ |
4506 | ||
1897b881 | 4507 | if (BB_PARTITION (a) != BB_PARTITION (b)) |
7562ed74 | 4508 | return false; |
4f18499c | 4509 | |
79f958cb | 4510 | /* Protect the loop latches. */ |
4511 | if (current_loops && b->loop_father->latch == b) | |
4512 | return false; | |
4513 | ||
d945554e | 4514 | /* If we would end up moving B's instructions, make sure it doesn't fall |
4515 | through into the exit block, since we cannot recover from a fallthrough | |
4516 | edge into the exit block occurring in the middle of a function. */ | |
4517 | if (NEXT_INSN (BB_END (a)) != BB_HEAD (b)) | |
4518 | { | |
4519 | edge e = find_fallthru_edge (b->succs); | |
34154e27 | 4520 | if (e && e->dest == EXIT_BLOCK_PTR_FOR_FN (cfun)) |
d945554e | 4521 | return false; |
4522 | } | |
4523 | ||
c60fa3a7 | 4524 | /* There must be exactly one edge in between the blocks. */ |
ea091dfd | 4525 | return (single_succ_p (a) |
4526 | && single_succ (a) == b | |
4527 | && single_pred_p (b) == 1 | |
cd665a06 | 4528 | && a != b |
c60fa3a7 | 4529 | /* Must be simple edge. */ |
ea091dfd | 4530 | && !(single_succ_edge (a)->flags & EDGE_COMPLEX) |
34154e27 | 4531 | && a != ENTRY_BLOCK_PTR_FOR_FN (cfun) |
4532 | && b != EXIT_BLOCK_PTR_FOR_FN (cfun) | |
4aaec180 | 4533 | /* If the jump insn has side effects, we can't kill the edge. |
4534 | When not optimizing, try_redirect_by_replacing_jump will | |
4535 | not allow us to redirect an edge by replacing a table jump. */ | |
6d7dc5b9 | 4536 | && (!JUMP_P (BB_END (a)) |
4aaec180 | 4537 | || ((!optimize || reload_completed) |
5496dbfc | 4538 | ? simplejump_p (BB_END (a)) : onlyjump_p (BB_END (a))))); |
c60fa3a7 | 4539 | } |
4540 | ||
a53ff4c1 | 4541 | /* Merge block A and B. The blocks must be mergeable. */ |
4542 | ||
c60fa3a7 | 4543 | static void |
4544 | cfg_layout_merge_blocks (basic_block a, basic_block b) | |
4545 | { | |
18b762f0 | 4546 | bool forwarder_p = (b->flags & BB_FORWARDER_BLOCK) != 0; |
d4afc00c | 4547 | rtx insn; |
18b762f0 | 4548 | |
1b4345f7 | 4549 | gcc_checking_assert (cfg_layout_can_merge_blocks_p (a, b)); |
c60fa3a7 | 4550 | |
3072d30e | 4551 | if (dump_file) |
18b762f0 | 4552 | fprintf (dump_file, "Merging block %d into block %d...\n", b->index, |
4553 | a->index); | |
3072d30e | 4554 | |
c60fa3a7 | 4555 | /* If there was a CODE_LABEL beginning B, delete it. */ |
6d7dc5b9 | 4556 | if (LABEL_P (BB_HEAD (b))) |
7b07eae7 | 4557 | { |
7b07eae7 | 4558 | delete_insn (BB_HEAD (b)); |
4559 | } | |
c60fa3a7 | 4560 | |
4561 | /* We should have fallthru edge in a, or we can do dummy redirection to get | |
4562 | it cleaned up. */ | |
6d7dc5b9 | 4563 | if (JUMP_P (BB_END (a))) |
cd665a06 | 4564 | try_redirect_by_replacing_jump (EDGE_SUCC (a, 0), b, true); |
cc636d56 | 4565 | gcc_assert (!JUMP_P (BB_END (a))); |
c60fa3a7 | 4566 | |
36ebb5b6 | 4567 | /* When not optimizing and the edge is the only place in RTL which holds |
9c388755 | 4568 | some unique locus, emit a nop with that locus in between. */ |
8ddad41d | 4569 | if (!optimize) |
4570 | emit_nop_for_unique_locus_between (a, b); | |
9c388755 | 4571 | |
eda57d74 | 4572 | /* Move things from b->footer after a->footer. */ |
4573 | if (BB_FOOTER (b)) | |
c60fa3a7 | 4574 | { |
eda57d74 | 4575 | if (!BB_FOOTER (a)) |
4576 | BB_FOOTER (a) = BB_FOOTER (b); | |
4577 | else | |
4578 | { | |
4579 | rtx last = BB_FOOTER (a); | |
4580 | ||
4581 | while (NEXT_INSN (last)) | |
4582 | last = NEXT_INSN (last); | |
4583 | NEXT_INSN (last) = BB_FOOTER (b); | |
4584 | PREV_INSN (BB_FOOTER (b)) = last; | |
4585 | } | |
4586 | BB_FOOTER (b) = NULL; | |
4587 | } | |
4588 | ||
4589 | /* Move things from b->header before a->footer. | |
4590 | Note that this may include dead tablejump data, but we don't clean | |
4591 | those up until we go out of cfglayout mode. */ | |
4592 | if (BB_HEADER (b)) | |
4593 | { | |
4594 | if (! BB_FOOTER (a)) | |
4595 | BB_FOOTER (a) = BB_HEADER (b); | |
4596 | else | |
4597 | { | |
4598 | rtx last = BB_HEADER (b); | |
4599 | ||
4600 | while (NEXT_INSN (last)) | |
4601 | last = NEXT_INSN (last); | |
4602 | NEXT_INSN (last) = BB_FOOTER (a); | |
4603 | PREV_INSN (BB_FOOTER (a)) = last; | |
4604 | BB_FOOTER (a) = BB_HEADER (b); | |
4605 | } | |
43e94e51 | 4606 | BB_HEADER (b) = NULL; |
c60fa3a7 | 4607 | } |
4608 | ||
4609 | /* In the case basic blocks are not adjacent, move them around. */ | |
5496dbfc | 4610 | if (NEXT_INSN (BB_END (a)) != BB_HEAD (b)) |
c60fa3a7 | 4611 | { |
d4afc00c | 4612 | insn = unlink_insn_chain (BB_HEAD (b), BB_END (b)); |
f41d4683 | 4613 | |
d4afc00c | 4614 | emit_insn_after_noloc (insn, BB_END (a), a); |
c60fa3a7 | 4615 | } |
4616 | /* Otherwise just re-associate the instructions. */ | |
4617 | else | |
4618 | { | |
5496dbfc | 4619 | insn = BB_HEAD (b); |
5496dbfc | 4620 | BB_END (a) = BB_END (b); |
c60fa3a7 | 4621 | } |
4622 | ||
d4afc00c | 4623 | /* emit_insn_after_noloc doesn't call df_insn_change_bb. |
4624 | We need to explicitly call. */ | |
4625 | update_bb_for_insn_chain (insn, BB_END (b), a); | |
4626 | ||
4627 | /* Skip possible DELETED_LABEL insn. */ | |
4628 | if (!NOTE_INSN_BASIC_BLOCK_P (insn)) | |
4629 | insn = NEXT_INSN (insn); | |
4630 | gcc_assert (NOTE_INSN_BASIC_BLOCK_P (insn)); | |
eda57d74 | 4631 | BB_HEAD (b) = BB_END (b) = NULL; |
d4afc00c | 4632 | delete_insn (insn); |
4633 | ||
3072d30e | 4634 | df_bb_delete (b->index); |
4635 | ||
18b762f0 | 4636 | /* If B was a forwarder block, propagate the locus on the edge. */ |
8e7408e3 | 4637 | if (forwarder_p |
81ad108c | 4638 | && LOCATION_LOCUS (EDGE_SUCC (b, 0)->goto_locus) == UNKNOWN_LOCATION) |
18b762f0 | 4639 | EDGE_SUCC (b, 0)->goto_locus = EDGE_SUCC (a, 0)->goto_locus; |
4640 | ||
450d042a | 4641 | if (dump_file) |
18b762f0 | 4642 | fprintf (dump_file, "Merged blocks %d and %d.\n", a->index, b->index); |
c60fa3a7 | 4643 | } |
4644 | ||
4645 | /* Split edge E. */ | |
5f5d4cd1 | 4646 | |
c60fa3a7 | 4647 | static basic_block |
4648 | cfg_layout_split_edge (edge e) | |
4649 | { | |
c60fa3a7 | 4650 | basic_block new_bb = |
34154e27 | 4651 | create_basic_block (e->src != ENTRY_BLOCK_PTR_FOR_FN (cfun) |
5496dbfc | 4652 | ? NEXT_INSN (BB_END (e->src)) : get_insns (), |
c60fa3a7 | 4653 | NULL_RTX, e->src); |
4654 | ||
34154e27 | 4655 | if (e->dest == EXIT_BLOCK_PTR_FOR_FN (cfun)) |
e1b2b77c | 4656 | BB_COPY_PARTITION (new_bb, e->src); |
4657 | else | |
4658 | BB_COPY_PARTITION (new_bb, e->dest); | |
3bdc4312 | 4659 | make_edge (new_bb, e->dest, EDGE_FALLTHRU); |
c60fa3a7 | 4660 | redirect_edge_and_branch_force (e, new_bb); |
4661 | ||
4662 | return new_bb; | |
4663 | } | |
4664 | ||
5f5d4cd1 | 4665 | /* Do postprocessing after making a forwarder block joined by edge FALLTHRU. */ |
4666 | ||
4667 | static void | |
4668 | rtl_make_forwarder_block (edge fallthru ATTRIBUTE_UNUSED) | |
4669 | { | |
4670 | } | |
4671 | ||
9631926a | 4672 | /* Return true if BB contains only labels or non-executable |
4673 | instructions. */ | |
4674 | ||
4675 | static bool | |
4676 | rtl_block_empty_p (basic_block bb) | |
4677 | { | |
4678 | rtx insn; | |
4679 | ||
34154e27 | 4680 | if (bb == ENTRY_BLOCK_PTR_FOR_FN (cfun) |
4681 | || bb == EXIT_BLOCK_PTR_FOR_FN (cfun)) | |
9631926a | 4682 | return true; |
4683 | ||
4684 | FOR_BB_INSNS (bb, insn) | |
4685 | if (NONDEBUG_INSN_P (insn) && !any_uncondjump_p (insn)) | |
4686 | return false; | |
4687 | ||
4688 | return true; | |
4689 | } | |
4690 | ||
4691 | /* Split a basic block if it ends with a conditional branch and if | |
4692 | the other part of the block is not empty. */ | |
4693 | ||
4694 | static basic_block | |
4695 | rtl_split_block_before_cond_jump (basic_block bb) | |
4696 | { | |
4697 | rtx insn; | |
4698 | rtx split_point = NULL; | |
4699 | rtx last = NULL; | |
4700 | bool found_code = false; | |
4701 | ||
4702 | FOR_BB_INSNS (bb, insn) | |
4703 | { | |
4704 | if (any_condjump_p (insn)) | |
4705 | split_point = last; | |
4706 | else if (NONDEBUG_INSN_P (insn)) | |
4707 | found_code = true; | |
4708 | last = insn; | |
4709 | } | |
4710 | ||
4711 | /* Did not find everything. */ | |
4712 | if (found_code && split_point) | |
4713 | return split_block (bb, split_point)->dest; | |
4714 | else | |
4715 | return NULL; | |
4716 | } | |
4717 | ||
4ee9c684 | 4718 | /* Return 1 if BB ends with a call, possibly followed by some |
4719 | instructions that must stay with the call, 0 otherwise. */ | |
4720 | ||
4721 | static bool | |
47aaf6e6 | 4722 | rtl_block_ends_with_call_p (basic_block bb) |
4ee9c684 | 4723 | { |
4724 | rtx insn = BB_END (bb); | |
4725 | ||
6d7dc5b9 | 4726 | while (!CALL_P (insn) |
4ee9c684 | 4727 | && insn != BB_HEAD (bb) |
f69dfa18 | 4728 | && (keep_with_call_p (insn) |
9845d120 | 4729 | || NOTE_P (insn) |
4730 | || DEBUG_INSN_P (insn))) | |
4ee9c684 | 4731 | insn = PREV_INSN (insn); |
6d7dc5b9 | 4732 | return (CALL_P (insn)); |
4ee9c684 | 4733 | } |
4734 | ||
4735 | /* Return 1 if BB ends with a conditional branch, 0 otherwise. */ | |
4736 | ||
4737 | static bool | |
5493cb9a | 4738 | rtl_block_ends_with_condjump_p (const_basic_block bb) |
4ee9c684 | 4739 | { |
4740 | return any_condjump_p (BB_END (bb)); | |
4741 | } | |
4742 | ||
4743 | /* Return true if we need to add fake edge to exit. | |
4744 | Helper function for rtl_flow_call_edges_add. */ | |
4745 | ||
4746 | static bool | |
5493cb9a | 4747 | need_fake_edge_p (const_rtx insn) |
4ee9c684 | 4748 | { |
4749 | if (!INSN_P (insn)) | |
4750 | return false; | |
4751 | ||
6d7dc5b9 | 4752 | if ((CALL_P (insn) |
4ee9c684 | 4753 | && !SIBLING_CALL_P (insn) |
4754 | && !find_reg_note (insn, REG_NORETURN, NULL) | |
9c2a0c05 | 4755 | && !(RTL_CONST_OR_PURE_CALL_P (insn)))) |
4ee9c684 | 4756 | return true; |
4757 | ||
4758 | return ((GET_CODE (PATTERN (insn)) == ASM_OPERANDS | |
4759 | && MEM_VOLATILE_P (PATTERN (insn))) | |
4760 | || (GET_CODE (PATTERN (insn)) == PARALLEL | |
4761 | && asm_noperands (insn) != -1 | |
4762 | && MEM_VOLATILE_P (XVECEXP (PATTERN (insn), 0, 0))) | |
4763 | || GET_CODE (PATTERN (insn)) == ASM_INPUT); | |
4764 | } | |
4765 | ||
4766 | /* Add fake edges to the function exit for any non constant and non noreturn | |
4767 | calls, volatile inline assembly in the bitmap of blocks specified by | |
4768 | BLOCKS or to the whole CFG if BLOCKS is zero. Return the number of blocks | |
4769 | that were split. | |
4770 | ||
4771 | The goal is to expose cases in which entering a basic block does not imply | |
4772 | that all subsequent instructions must be executed. */ | |
4773 | ||
4774 | static int | |
4775 | rtl_flow_call_edges_add (sbitmap blocks) | |
4776 | { | |
4777 | int i; | |
4778 | int blocks_split = 0; | |
fe672ac0 | 4779 | int last_bb = last_basic_block_for_fn (cfun); |
4ee9c684 | 4780 | bool check_last_block = false; |
4781 | ||
a28770e1 | 4782 | if (n_basic_blocks_for_fn (cfun) == NUM_FIXED_BLOCKS) |
4ee9c684 | 4783 | return 0; |
4784 | ||
4785 | if (! blocks) | |
4786 | check_last_block = true; | |
4787 | else | |
34154e27 | 4788 | check_last_block = bitmap_bit_p (blocks, |
4789 | EXIT_BLOCK_PTR_FOR_FN (cfun)->prev_bb->index); | |
4ee9c684 | 4790 | |
4791 | /* In the last basic block, before epilogue generation, there will be | |
4792 | a fallthru edge to EXIT. Special care is required if the last insn | |
4793 | of the last basic block is a call because make_edge folds duplicate | |
4794 | edges, which would result in the fallthru edge also being marked | |
4795 | fake, which would result in the fallthru edge being removed by | |
4796 | remove_fake_edges, which would result in an invalid CFG. | |
4797 | ||
4798 | Moreover, we can't elide the outgoing fake edge, since the block | |
4799 | profiler needs to take this into account in order to solve the minimal | |
4800 | spanning tree in the case that the call doesn't return. | |
4801 | ||
4802 | Handle this by adding a dummy instruction in a new last basic block. */ | |
4803 | if (check_last_block) | |
4804 | { | |
34154e27 | 4805 | basic_block bb = EXIT_BLOCK_PTR_FOR_FN (cfun)->prev_bb; |
4ee9c684 | 4806 | rtx insn = BB_END (bb); |
4807 | ||
4808 | /* Back up past insns that must be kept in the same block as a call. */ | |
4809 | while (insn != BB_HEAD (bb) | |
4810 | && keep_with_call_p (insn)) | |
4811 | insn = PREV_INSN (insn); | |
4812 | ||
4813 | if (need_fake_edge_p (insn)) | |
4814 | { | |
4815 | edge e; | |
4816 | ||
34154e27 | 4817 | e = find_edge (bb, EXIT_BLOCK_PTR_FOR_FN (cfun)); |
c6356c17 | 4818 | if (e) |
4819 | { | |
18b42941 | 4820 | insert_insn_on_edge (gen_use (const0_rtx), e); |
c6356c17 | 4821 | commit_edge_insertions (); |
4822 | } | |
4ee9c684 | 4823 | } |
4824 | } | |
4825 | ||
4826 | /* Now add fake edges to the function exit for any non constant | |
4827 | calls since there is no way that we can determine if they will | |
4828 | return or not... */ | |
4829 | ||
4d2e5d52 | 4830 | for (i = NUM_FIXED_BLOCKS; i < last_bb; i++) |
4ee9c684 | 4831 | { |
f5a6b05f | 4832 | basic_block bb = BASIC_BLOCK_FOR_FN (cfun, i); |
4ee9c684 | 4833 | rtx insn; |
4834 | rtx prev_insn; | |
4835 | ||
4836 | if (!bb) | |
4837 | continue; | |
4838 | ||
08b7917c | 4839 | if (blocks && !bitmap_bit_p (blocks, i)) |
4ee9c684 | 4840 | continue; |
4841 | ||
4842 | for (insn = BB_END (bb); ; insn = prev_insn) | |
4843 | { | |
4844 | prev_insn = PREV_INSN (insn); | |
4845 | if (need_fake_edge_p (insn)) | |
4846 | { | |
4847 | edge e; | |
4848 | rtx split_at_insn = insn; | |
4849 | ||
4850 | /* Don't split the block between a call and an insn that should | |
a0c938f0 | 4851 | remain in the same block as the call. */ |
6d7dc5b9 | 4852 | if (CALL_P (insn)) |
4ee9c684 | 4853 | while (split_at_insn != BB_END (bb) |
4854 | && keep_with_call_p (NEXT_INSN (split_at_insn))) | |
4855 | split_at_insn = NEXT_INSN (split_at_insn); | |
4856 | ||
4857 | /* The handling above of the final block before the epilogue | |
a0c938f0 | 4858 | should be enough to verify that there is no edge to the exit |
4ee9c684 | 4859 | block in CFG already. Calling make_edge in such case would |
4860 | cause us to mark that edge as fake and remove it later. */ | |
4861 | ||
4862 | #ifdef ENABLE_CHECKING | |
4863 | if (split_at_insn == BB_END (bb)) | |
cd665a06 | 4864 | { |
34154e27 | 4865 | e = find_edge (bb, EXIT_BLOCK_PTR_FOR_FN (cfun)); |
c6356c17 | 4866 | gcc_assert (e == NULL); |
cd665a06 | 4867 | } |
4ee9c684 | 4868 | #endif |
4869 | ||
4870 | /* Note that the following may create a new basic block | |
4871 | and renumber the existing basic blocks. */ | |
4872 | if (split_at_insn != BB_END (bb)) | |
4873 | { | |
4874 | e = split_block (bb, split_at_insn); | |
4875 | if (e) | |
4876 | blocks_split++; | |
4877 | } | |
4878 | ||
34154e27 | 4879 | make_edge (bb, EXIT_BLOCK_PTR_FOR_FN (cfun), EDGE_FAKE); |
4ee9c684 | 4880 | } |
4881 | ||
4882 | if (insn == BB_HEAD (bb)) | |
4883 | break; | |
4884 | } | |
4885 | } | |
4886 | ||
4887 | if (blocks_split) | |
4888 | verify_flow_info (); | |
4889 | ||
4890 | return blocks_split; | |
4891 | } | |
4892 | ||
c50ae675 | 4893 | /* Add COMP_RTX as a condition at end of COND_BB. FIRST_HEAD is |
d90dbd3e | 4894 | the conditional branch target, SECOND_HEAD should be the fall-thru |
c50ae675 | 4895 | there is no need to handle this here the loop versioning code handles |
4896 | this. the reason for SECON_HEAD is that it is needed for condition | |
4897 | in trees, and this should be of the same type since it is a hook. */ | |
4898 | static void | |
4899 | rtl_lv_add_condition_to_bb (basic_block first_head , | |
a0c938f0 | 4900 | basic_block second_head ATTRIBUTE_UNUSED, |
4901 | basic_block cond_bb, void *comp_rtx) | |
c50ae675 | 4902 | { |
4903 | rtx label, seq, jump; | |
4904 | rtx op0 = XEXP ((rtx)comp_rtx, 0); | |
4905 | rtx op1 = XEXP ((rtx)comp_rtx, 1); | |
4906 | enum rtx_code comp = GET_CODE ((rtx)comp_rtx); | |
4907 | enum machine_mode mode; | |
4908 | ||
4909 | ||
4910 | label = block_label (first_head); | |
4911 | mode = GET_MODE (op0); | |
4912 | if (mode == VOIDmode) | |
4913 | mode = GET_MODE (op1); | |
4914 | ||
4915 | start_sequence (); | |
4916 | op0 = force_operand (op0, NULL_RTX); | |
4917 | op1 = force_operand (op1, NULL_RTX); | |
4918 | do_compare_rtx_and_jump (op0, op1, comp, 0, | |
79ab74cc | 4919 | mode, NULL_RTX, NULL_RTX, label, -1); |
c50ae675 | 4920 | jump = get_last_insn (); |
4921 | JUMP_LABEL (jump) = label; | |
4922 | LABEL_NUSES (label)++; | |
4923 | seq = get_insns (); | |
4924 | end_sequence (); | |
4925 | ||
4926 | /* Add the new cond , in the new head. */ | |
9af5ce0c | 4927 | emit_insn_after (seq, BB_END (cond_bb)); |
c50ae675 | 4928 | } |
4929 | ||
4930 | ||
4931 | /* Given a block B with unconditional branch at its end, get the | |
4932 | store the return the branch edge and the fall-thru edge in | |
4933 | BRANCH_EDGE and FALLTHRU_EDGE respectively. */ | |
4934 | static void | |
4935 | rtl_extract_cond_bb_edges (basic_block b, edge *branch_edge, | |
4936 | edge *fallthru_edge) | |
4937 | { | |
4938 | edge e = EDGE_SUCC (b, 0); | |
4939 | ||
4940 | if (e->flags & EDGE_FALLTHRU) | |
4941 | { | |
4942 | *fallthru_edge = e; | |
4943 | *branch_edge = EDGE_SUCC (b, 1); | |
4944 | } | |
4945 | else | |
4946 | { | |
4947 | *branch_edge = e; | |
4948 | *fallthru_edge = EDGE_SUCC (b, 1); | |
4949 | } | |
4950 | } | |
4951 | ||
e0dde8f8 | 4952 | void |
4953 | init_rtl_bb_info (basic_block bb) | |
4954 | { | |
43e94e51 | 4955 | gcc_assert (!bb->il.x.rtl); |
4956 | bb->il.x.head_ = NULL; | |
25a27413 | 4957 | bb->il.x.rtl = ggc_cleared_alloc<rtl_bb_info> (); |
e0dde8f8 | 4958 | } |
4959 | ||
611d2ac1 | 4960 | /* Returns true if it is possible to remove edge E by redirecting |
4961 | it to the destination of the other edge from E->src. */ | |
4962 | ||
4963 | static bool | |
5493cb9a | 4964 | rtl_can_remove_branch_p (const_edge e) |
611d2ac1 | 4965 | { |
5493cb9a | 4966 | const_basic_block src = e->src; |
4967 | const_basic_block target = EDGE_SUCC (src, EDGE_SUCC (src, 0) == e)->dest; | |
4968 | const_rtx insn = BB_END (src), set; | |
611d2ac1 | 4969 | |
4970 | /* The conditions are taken from try_redirect_by_replacing_jump. */ | |
34154e27 | 4971 | if (target == EXIT_BLOCK_PTR_FOR_FN (cfun)) |
611d2ac1 | 4972 | return false; |
4973 | ||
4974 | if (e->flags & (EDGE_ABNORMAL_CALL | EDGE_EH)) | |
4975 | return false; | |
4976 | ||
aa78dca5 | 4977 | if (BB_PARTITION (src) != BB_PARTITION (target)) |
611d2ac1 | 4978 | return false; |
4979 | ||
4980 | if (!onlyjump_p (insn) | |
4981 | || tablejump_p (insn, NULL, NULL)) | |
4982 | return false; | |
4983 | ||
4984 | set = single_set (insn); | |
4985 | if (!set || side_effects_p (set)) | |
4986 | return false; | |
4987 | ||
4988 | return true; | |
4989 | } | |
4990 | ||
0a55d497 | 4991 | static basic_block |
4992 | rtl_duplicate_bb (basic_block bb) | |
4993 | { | |
4994 | bb = cfg_layout_duplicate_bb (bb); | |
4995 | bb->aux = NULL; | |
4996 | return bb; | |
4997 | } | |
4998 | ||
98193482 | 4999 | /* Do book-keeping of basic block BB for the profile consistency checker. |
5000 | If AFTER_PASS is 0, do pre-pass accounting, or if AFTER_PASS is 1 | |
5001 | then do post-pass accounting. Store the counting in RECORD. */ | |
5002 | static void | |
5003 | rtl_account_profile_record (basic_block bb, int after_pass, | |
5004 | struct profile_record *record) | |
5005 | { | |
5006 | rtx insn; | |
5007 | FOR_BB_INSNS (bb, insn) | |
5008 | if (INSN_P (insn)) | |
5009 | { | |
5010 | record->size[after_pass] | |
5011 | += insn_rtx_cost (PATTERN (insn), false); | |
f26d8580 | 5012 | if (profile_status_for_fn (cfun) == PROFILE_READ) |
98193482 | 5013 | record->time[after_pass] |
5014 | += insn_rtx_cost (PATTERN (insn), true) * bb->count; | |
f26d8580 | 5015 | else if (profile_status_for_fn (cfun) == PROFILE_GUESSED) |
98193482 | 5016 | record->time[after_pass] |
5017 | += insn_rtx_cost (PATTERN (insn), true) * bb->frequency; | |
5018 | } | |
5019 | } | |
5020 | ||
1026363d | 5021 | /* Implementation of CFG manipulation for linearized RTL. */ |
5022 | struct cfg_hooks rtl_cfg_hooks = { | |
5f5d4cd1 | 5023 | "rtl", |
1026363d | 5024 | rtl_verify_flow_info, |
028f8cc7 | 5025 | rtl_dump_bb, |
e079344a | 5026 | rtl_dump_bb_for_graph, |
c60fa3a7 | 5027 | rtl_create_basic_block, |
1026363d | 5028 | rtl_redirect_edge_and_branch, |
5029 | rtl_redirect_edge_and_branch_force, | |
611d2ac1 | 5030 | rtl_can_remove_branch_p, |
1026363d | 5031 | rtl_delete_block, |
5032 | rtl_split_block, | |
5f5d4cd1 | 5033 | rtl_move_block_after, |
c60fa3a7 | 5034 | rtl_can_merge_blocks, /* can_merge_blocks_p */ |
5035 | rtl_merge_blocks, | |
4ee9c684 | 5036 | rtl_predict_edge, |
5037 | rtl_predicted_by_p, | |
0a55d497 | 5038 | cfg_layout_can_duplicate_bb_p, |
5039 | rtl_duplicate_bb, | |
5f5d4cd1 | 5040 | rtl_split_edge, |
5041 | rtl_make_forwarder_block, | |
4ee9c684 | 5042 | rtl_tidy_fallthru_edge, |
202bbc06 | 5043 | rtl_force_nonfallthru, |
4ee9c684 | 5044 | rtl_block_ends_with_call_p, |
5045 | rtl_block_ends_with_condjump_p, | |
26b12c91 | 5046 | rtl_flow_call_edges_add, |
5047 | NULL, /* execute_on_growing_pred */ | |
c50ae675 | 5048 | NULL, /* execute_on_shrinking_pred */ |
5049 | NULL, /* duplicate loop for trees */ | |
5050 | NULL, /* lv_add_condition_to_bb */ | |
5051 | NULL, /* lv_adjust_loop_header_phi*/ | |
5052 | NULL, /* extract_cond_bb_edges */ | |
9631926a | 5053 | NULL, /* flush_pending_stmts */ |
5054 | rtl_block_empty_p, /* block_empty_p */ | |
5055 | rtl_split_block_before_cond_jump, /* split_block_before_cond_jump */ | |
98193482 | 5056 | rtl_account_profile_record, |
1026363d | 5057 | }; |
5058 | ||
5059 | /* Implementation of CFG manipulation for cfg layout RTL, where | |
5060 | basic block connected via fallthru edges does not have to be adjacent. | |
5061 | This representation will hopefully become the default one in future | |
5062 | version of the compiler. */ | |
4ee9c684 | 5063 | |
1026363d | 5064 | struct cfg_hooks cfg_layout_rtl_cfg_hooks = { |
5f5d4cd1 | 5065 | "cfglayout mode", |
c60fa3a7 | 5066 | rtl_verify_flow_info_1, |
028f8cc7 | 5067 | rtl_dump_bb, |
e079344a | 5068 | rtl_dump_bb_for_graph, |
c60fa3a7 | 5069 | cfg_layout_create_basic_block, |
1026363d | 5070 | cfg_layout_redirect_edge_and_branch, |
5071 | cfg_layout_redirect_edge_and_branch_force, | |
611d2ac1 | 5072 | rtl_can_remove_branch_p, |
1026363d | 5073 | cfg_layout_delete_block, |
5074 | cfg_layout_split_block, | |
5f5d4cd1 | 5075 | rtl_move_block_after, |
c60fa3a7 | 5076 | cfg_layout_can_merge_blocks_p, |
5077 | cfg_layout_merge_blocks, | |
4ee9c684 | 5078 | rtl_predict_edge, |
5079 | rtl_predicted_by_p, | |
5080 | cfg_layout_can_duplicate_bb_p, | |
5081 | cfg_layout_duplicate_bb, | |
5f5d4cd1 | 5082 | cfg_layout_split_edge, |
5083 | rtl_make_forwarder_block, | |
202bbc06 | 5084 | NULL, /* tidy_fallthru_edge */ |
5085 | rtl_force_nonfallthru, | |
4ee9c684 | 5086 | rtl_block_ends_with_call_p, |
5087 | rtl_block_ends_with_condjump_p, | |
26b12c91 | 5088 | rtl_flow_call_edges_add, |
5089 | NULL, /* execute_on_growing_pred */ | |
c50ae675 | 5090 | NULL, /* execute_on_shrinking_pred */ |
5091 | duplicate_loop_to_header_edge, /* duplicate loop for trees */ | |
5092 | rtl_lv_add_condition_to_bb, /* lv_add_condition_to_bb */ | |
5093 | NULL, /* lv_adjust_loop_header_phi*/ | |
5094 | rtl_extract_cond_bb_edges, /* extract_cond_bb_edges */ | |
9631926a | 5095 | NULL, /* flush_pending_stmts */ |
5096 | rtl_block_empty_p, /* block_empty_p */ | |
5097 | rtl_split_block_before_cond_jump, /* split_block_before_cond_jump */ | |
98193482 | 5098 | rtl_account_profile_record, |
1026363d | 5099 | }; |
23a070f3 | 5100 | |
5101 | #include "gt-cfgrtl.h" |