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ca6c03ca | 1 | /* Control flow graph manipulation code for GNU compiler. |
d1e082c2 | 2 | Copyright (C) 1987-2013 Free Software Foundation, Inc. |
ca6c03ca JH |
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 | |
9dcd6f09 | 8 | Software Foundation; either version 3, or (at your option) any later |
ca6c03ca JH |
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 | |
9dcd6f09 NC |
17 | along with GCC; see the file COPYING3. If not see |
18 | <http://www.gnu.org/licenses/>. */ | |
ca6c03ca | 19 | |
5f0d2358 RK |
20 | /* This file contains low level functions to manipulate the CFG and analyze it |
21 | that are aware of the RTL intermediate language. | |
ca6c03ca JH |
22 | |
23 | Available functionality: | |
bc35512f | 24 | - Basic CFG/RTL manipulation API documented in cfghooks.h |
5f0d2358 | 25 | - CFG-aware instruction chain manipulation |
ca6c03ca | 26 | delete_insn, delete_insn_chain |
bc35512f JH |
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 | |
ba5e9aca EB |
31 | - CFG fixing after coarse manipulation |
32 | fixup_abnormal_edges | |
bc35512f JH |
33 | |
34 | Functions not supposed for generic use: | |
5f0d2358 | 35 | - Infrastructure to determine quickly basic block for insn |
ca6c03ca | 36 | compute_bb_for_insn, update_bb_for_insn, set_block_for_insn, |
5f0d2358 | 37 | - Edge redirection with updating and optimizing of insn chain |
bc35512f | 38 | block_label, tidy_fallthru_edge, force_nonfallthru */ |
ca6c03ca JH |
39 | \f |
40 | #include "config.h" | |
41 | #include "system.h" | |
4977bab6 ZW |
42 | #include "coretypes.h" |
43 | #include "tm.h" | |
ca6c03ca | 44 | #include "tree.h" |
ca6c03ca JH |
45 | #include "hard-reg-set.h" |
46 | #include "basic-block.h" | |
3371a64f | 47 | #include "bb-reorder.h" |
ca6c03ca JH |
48 | #include "regs.h" |
49 | #include "flags.h" | |
ca6c03ca JH |
50 | #include "function.h" |
51 | #include "except.h" | |
0cbd9993 | 52 | #include "rtl-error.h" |
ca6c03ca JH |
53 | #include "tm_p.h" |
54 | #include "obstack.h" | |
2a34bece | 55 | #include "insn-attr.h" |
0a2ed1f1 | 56 | #include "insn-config.h" |
ff25ef99 | 57 | #include "expr.h" |
9fb32434 | 58 | #include "target.h" |
677f3fa8 | 59 | #include "common/common-target.h" |
1cb7dfc3 | 60 | #include "cfgloop.h" |
5e2d947c | 61 | #include "ggc.h" |
ef330312 | 62 | #include "tree-pass.h" |
6fb5fa3c | 63 | #include "df.h" |
ca6c03ca | 64 | |
78bde837 SB |
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); | |
9678086d KG |
77 | static int can_delete_note_p (const_rtx); |
78 | static int can_delete_label_p (const_rtx); | |
d329e058 | 79 | static basic_block rtl_split_edge (edge); |
f470c378 | 80 | static bool rtl_move_block_after (basic_block, basic_block); |
d329e058 | 81 | static int rtl_verify_flow_info (void); |
f470c378 | 82 | static basic_block cfg_layout_split_block (basic_block, void *); |
6de9cd9a | 83 | static edge cfg_layout_redirect_edge_and_branch (edge, basic_block); |
d329e058 AJ |
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); | |
6de9cd9a | 88 | static edge rtl_redirect_edge_and_branch (edge, basic_block); |
f470c378 | 89 | static basic_block rtl_split_block (basic_block, void *); |
a315c44c | 90 | static void rtl_dump_bb (FILE *, basic_block, int, int); |
d329e058 | 91 | static int rtl_verify_flow_info_1 (void); |
f470c378 | 92 | static void rtl_make_forwarder_block (edge); |
ca6c03ca JH |
93 | \f |
94 | /* Return true if NOTE is not one of the ones that must be kept paired, | |
5f0d2358 | 95 | so that we may simply delete it. */ |
ca6c03ca JH |
96 | |
97 | static int | |
9678086d | 98 | can_delete_note_p (const_rtx note) |
ca6c03ca | 99 | { |
cd9c1ca8 RH |
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 | } | |
ca6c03ca JH |
110 | } |
111 | ||
112 | /* True if a given label can be deleted. */ | |
113 | ||
114 | static int | |
9678086d | 115 | can_delete_label_p (const_rtx label) |
ca6c03ca | 116 | { |
5f0d2358 RK |
117 | return (!LABEL_PRESERVE_P (label) |
118 | /* User declared labels must be preserved. */ | |
119 | && LABEL_NAME (label) == 0 | |
610d2478 | 120 | && !in_expr_list_p (forced_labels, label)); |
ca6c03ca JH |
121 | } |
122 | ||
03fbe718 | 123 | /* Delete INSN by patching it out. */ |
ca6c03ca | 124 | |
03fbe718 | 125 | void |
d329e058 | 126 | delete_insn (rtx insn) |
ca6c03ca | 127 | { |
ca6c03ca JH |
128 | rtx note; |
129 | bool really_delete = true; | |
130 | ||
4b4bf941 | 131 | if (LABEL_P (insn)) |
ca6c03ca JH |
132 | { |
133 | /* Some labels can't be directly removed from the INSN chain, as they | |
c22cacf3 MS |
134 | might be references via variables, constant pool etc. |
135 | Convert them to the special NOTE_INSN_DELETED_LABEL note. */ | |
ca6c03ca JH |
136 | if (! can_delete_label_p (insn)) |
137 | { | |
138 | const char *name = LABEL_NAME (insn); | |
5e5df392 | 139 | basic_block bb = BLOCK_FOR_INSN (insn); |
03fbe718 | 140 | rtx bb_note = NEXT_INSN (insn); |
ca6c03ca JH |
141 | |
142 | really_delete = false; | |
143 | PUT_CODE (insn, NOTE); | |
a38e7aa5 | 144 | NOTE_KIND (insn) = NOTE_INSN_DELETED_LABEL; |
6773e15f | 145 | NOTE_DELETED_LABEL_NAME (insn) = name; |
03fbe718 | 146 | |
0f33baa9 | 147 | /* If the note following the label starts a basic block, and the |
5e5df392 | 148 | label is a member of the same basic block, interchange the two. */ |
0f33baa9 TV |
149 | if (bb_note != NULL_RTX |
150 | && NOTE_INSN_BASIC_BLOCK_P (bb_note) | |
5e5df392 TV |
151 | && bb != NULL |
152 | && bb == BLOCK_FOR_INSN (bb_note)) | |
03fbe718 TV |
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 | } | |
ca6c03ca | 159 | } |
5f0d2358 | 160 | |
ca6c03ca JH |
161 | remove_node_from_expr_list (insn, &nonlocal_goto_handler_labels); |
162 | } | |
163 | ||
164 | if (really_delete) | |
165 | { | |
cda94cbb | 166 | /* If this insn has already been deleted, something is very wrong. */ |
341c100f | 167 | gcc_assert (!INSN_DELETED_P (insn)); |
1f397f45 SB |
168 | if (INSN_P (insn)) |
169 | df_insn_delete (insn); | |
ca6c03ca JH |
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. */ | |
cf7c4aa6 | 176 | if (JUMP_P (insn)) |
9295a326 | 177 | { |
cf7c4aa6 HPN |
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 | |
4b4bf941 | 185 | && LABEL_P (XEXP (note, 0))) |
9295a326 JZ |
186 | { |
187 | LABEL_NUSES (XEXP (note, 0))--; | |
188 | remove_note (insn, note); | |
189 | } | |
190 | } | |
ca6c03ca | 191 | |
cf7c4aa6 HPN |
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 | ||
481683e1 | 200 | if (JUMP_TABLE_DATA_P (insn)) |
ca6c03ca JH |
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++) | |
a124fcda RH |
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. */ | |
4b4bf941 | 214 | if (!NOTE_P (label)) |
a124fcda RH |
215 | LABEL_NUSES (label)--; |
216 | } | |
ca6c03ca | 217 | } |
ca6c03ca JH |
218 | } |
219 | ||
3dec4024 | 220 | /* Like delete_insn but also purge dead edges from BB. */ |
9ed7b221 | 221 | |
03fbe718 | 222 | void |
d329e058 | 223 | delete_insn_and_edges (rtx insn) |
3dec4024 | 224 | { |
3dec4024 JH |
225 | bool purge = false; |
226 | ||
ba4f7968 | 227 | if (INSN_P (insn) |
3dec4024 | 228 | && BLOCK_FOR_INSN (insn) |
a813c111 | 229 | && BB_END (BLOCK_FOR_INSN (insn)) == insn) |
3dec4024 | 230 | purge = true; |
03fbe718 | 231 | delete_insn (insn); |
3dec4024 JH |
232 | if (purge) |
233 | purge_dead_edges (BLOCK_FOR_INSN (insn)); | |
3dec4024 JH |
234 | } |
235 | ||
ca6c03ca | 236 | /* Unlink a chain of insns between START and FINISH, leaving notes |
a7b87f73 ZD |
237 | that must be paired. If CLEAR_BB is true, we set bb field for |
238 | insns that cannot be removed to NULL. */ | |
ca6c03ca JH |
239 | |
240 | void | |
a7b87f73 | 241 | delete_insn_chain (rtx start, rtx finish, bool clear_bb) |
ca6c03ca | 242 | { |
03fbe718 | 243 | rtx prev, current; |
ca6c03ca | 244 | |
5f0d2358 RK |
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. */ | |
03fbe718 | 248 | current = finish; |
ca6c03ca JH |
249 | while (1) |
250 | { | |
03fbe718 TV |
251 | prev = PREV_INSN (current); |
252 | if (NOTE_P (current) && !can_delete_note_p (current)) | |
ca6c03ca JH |
253 | ; |
254 | else | |
03fbe718 | 255 | delete_insn (current); |
ca6c03ca | 256 | |
03fbe718 TV |
257 | if (clear_bb && !INSN_DELETED_P (current)) |
258 | set_block_for_insn (current, NULL); | |
a7b87f73 | 259 | |
03fbe718 | 260 | if (current == start) |
ca6c03ca | 261 | break; |
03fbe718 | 262 | current = prev; |
ca6c03ca JH |
263 | } |
264 | } | |
265 | \f | |
5f0d2358 RK |
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 | |
918ed612 ZD |
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. */ | |
ca6c03ca JH |
273 | |
274 | basic_block | |
d329e058 | 275 | create_basic_block_structure (rtx head, rtx end, rtx bb_note, basic_block after) |
ca6c03ca JH |
276 | { |
277 | basic_block bb; | |
278 | ||
279 | if (bb_note | |
ca6c03ca JH |
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 | ||
4b4bf941 | 287 | if (LABEL_P (head)) |
ca6c03ca JH |
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) | |
ba4f7968 | 296 | reorder_insns_nobb (bb_note, bb_note, after); |
ca6c03ca JH |
297 | } |
298 | else | |
299 | { | |
300 | /* Otherwise we must create a note and a basic block structure. */ | |
301 | ||
302 | bb = alloc_block (); | |
303 | ||
5e2d947c | 304 | init_rtl_bb_info (bb); |
ca6c03ca | 305 | if (!head && !end) |
5f0d2358 RK |
306 | head = end = bb_note |
307 | = emit_note_after (NOTE_INSN_BASIC_BLOCK, get_last_insn ()); | |
4b4bf941 | 308 | else if (LABEL_P (head) && end) |
ca6c03ca JH |
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 | } | |
5f0d2358 | 321 | |
ca6c03ca JH |
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 | ||
a813c111 SB |
329 | BB_HEAD (bb) = head; |
330 | BB_END (bb) = end; | |
8b1c6fd7 | 331 | bb->index = last_basic_block_for_fn (cfun)++; |
5e2d947c | 332 | bb->flags = BB_NEW | BB_RTL; |
918ed612 | 333 | link_block (bb, after); |
557c4b49 | 334 | SET_BASIC_BLOCK_FOR_FN (cfun, bb->index, bb); |
6fb5fa3c | 335 | df_bb_refs_record (bb->index, false); |
ba4f7968 | 336 | update_bb_for_insn (bb); |
076c7ab8 | 337 | BB_SET_PARTITION (bb, BB_UNPARTITIONED); |
ca6c03ca JH |
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 | ||
5f0d2358 | 346 | /* Create new basic block consisting of instructions in between HEAD and END |
ffe14686 AM |
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. */ | |
ca6c03ca | 350 | |
bc35512f JH |
351 | static basic_block |
352 | rtl_create_basic_block (void *headp, void *endp, basic_block after) | |
ca6c03ca | 353 | { |
ae50c0cb | 354 | rtx head = (rtx) headp, end = (rtx) endp; |
ca6c03ca | 355 | basic_block bb; |
0b17ab2f | 356 | |
7eca0767 | 357 | /* Grow the basic block array if needed. */ |
8b1c6fd7 DM |
358 | if ((size_t) last_basic_block_for_fn (cfun) |
359 | >= basic_block_info_for_fn (cfun)->length ()) | |
7eca0767 | 360 | { |
8b1c6fd7 DM |
361 | size_t new_size = |
362 | (last_basic_block_for_fn (cfun) | |
363 | + (last_basic_block_for_fn (cfun) + 3) / 4); | |
c5f05f68 | 364 | vec_safe_grow_cleared (basic_block_info_for_fn (cfun), new_size); |
7eca0767 | 365 | } |
0b17ab2f | 366 | |
0cae8d31 | 367 | n_basic_blocks_for_fn (cfun)++; |
ca6c03ca | 368 | |
852c6ec7 | 369 | bb = create_basic_block_structure (head, end, NULL, after); |
ca6c03ca JH |
370 | bb->aux = NULL; |
371 | return bb; | |
372 | } | |
bc35512f JH |
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 | ||
bc35512f JH |
379 | return newbb; |
380 | } | |
ca6c03ca JH |
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 | ||
f0fda11c | 390 | static void |
d329e058 | 391 | rtl_delete_block (basic_block b) |
ca6c03ca | 392 | { |
96370780 | 393 | rtx insn, end; |
ca6c03ca JH |
394 | |
395 | /* If the head of this block is a CODE_LABEL, then it might be the | |
f39e46ba SB |
396 | label for an exception handler which can't be reached. We need |
397 | to remove the label from the exception_handler_label list. */ | |
a813c111 | 398 | insn = BB_HEAD (b); |
ca6c03ca | 399 | |
96370780 | 400 | end = get_last_bb_insn (b); |
ca6c03ca JH |
401 | |
402 | /* Selectively delete the entire chain. */ | |
a813c111 | 403 | BB_HEAD (b) = NULL; |
a7b87f73 ZD |
404 | delete_insn_chain (insn, end, true); |
405 | ||
6fb5fa3c DB |
406 | |
407 | if (dump_file) | |
408 | fprintf (dump_file, "deleting block %d\n", b->index); | |
409 | df_bb_delete (b->index); | |
ca6c03ca JH |
410 | } |
411 | \f | |
852c6ec7 | 412 | /* Records the basic block struct in BLOCK_FOR_INSN for every insn. */ |
ca6c03ca JH |
413 | |
414 | void | |
d329e058 | 415 | compute_bb_for_insn (void) |
ca6c03ca | 416 | { |
e0082a72 | 417 | basic_block bb; |
ca6c03ca | 418 | |
11cd3bed | 419 | FOR_EACH_BB_FN (bb, cfun) |
ca6c03ca | 420 | { |
a813c111 | 421 | rtx end = BB_END (bb); |
5f0d2358 | 422 | rtx insn; |
ca6c03ca | 423 | |
a813c111 | 424 | for (insn = BB_HEAD (bb); ; insn = NEXT_INSN (insn)) |
ca6c03ca | 425 | { |
ba4f7968 | 426 | BLOCK_FOR_INSN (insn) = bb; |
ca6c03ca JH |
427 | if (insn == end) |
428 | break; | |
ca6c03ca JH |
429 | } |
430 | } | |
431 | } | |
432 | ||
433 | /* Release the basic_block_for_insn array. */ | |
434 | ||
c2924966 | 435 | unsigned int |
d329e058 | 436 | free_bb_for_insn (void) |
ca6c03ca | 437 | { |
ba4f7968 JH |
438 | rtx insn; |
439 | for (insn = get_insns (); insn; insn = NEXT_INSN (insn)) | |
4b4bf941 | 440 | if (!BARRIER_P (insn)) |
ba4f7968 | 441 | BLOCK_FOR_INSN (insn) = NULL; |
c2924966 | 442 | return 0; |
ca6c03ca JH |
443 | } |
444 | ||
2a34bece EB |
445 | static unsigned int |
446 | rest_of_pass_free_cfg (void) | |
447 | { | |
448 | #ifdef DELAY_SLOTS | |
449 | /* The resource.c machinery uses DF but the CFG isn't guaranteed to be | |
450 | valid at that point so it would be too late to call df_analyze. */ | |
451 | if (optimize > 0 && flag_delayed_branch) | |
ad78b8a6 EB |
452 | { |
453 | df_note_add_problem (); | |
454 | df_analyze (); | |
455 | } | |
2a34bece EB |
456 | #endif |
457 | ||
3371a64f TJ |
458 | if (crtl->has_bb_partition) |
459 | insert_section_boundary_note (); | |
460 | ||
2a34bece EB |
461 | free_bb_for_insn (); |
462 | return 0; | |
463 | } | |
464 | ||
27a4cd48 DM |
465 | namespace { |
466 | ||
467 | const pass_data pass_data_free_cfg = | |
468 | { | |
469 | RTL_PASS, /* type */ | |
470 | "*free_cfg", /* name */ | |
471 | OPTGROUP_NONE, /* optinfo_flags */ | |
472 | false, /* has_gate */ | |
473 | true, /* has_execute */ | |
474 | TV_NONE, /* tv_id */ | |
475 | 0, /* properties_required */ | |
476 | 0, /* properties_provided */ | |
477 | PROP_cfg, /* properties_destroyed */ | |
478 | 0, /* todo_flags_start */ | |
479 | 0, /* todo_flags_finish */ | |
ef330312 PB |
480 | }; |
481 | ||
27a4cd48 DM |
482 | class pass_free_cfg : public rtl_opt_pass |
483 | { | |
484 | public: | |
c3284718 RS |
485 | pass_free_cfg (gcc::context *ctxt) |
486 | : rtl_opt_pass (pass_data_free_cfg, ctxt) | |
27a4cd48 DM |
487 | {} |
488 | ||
489 | /* opt_pass methods: */ | |
490 | unsigned int execute () { return rest_of_pass_free_cfg (); } | |
491 | ||
492 | }; // class pass_free_cfg | |
493 | ||
494 | } // anon namespace | |
495 | ||
496 | rtl_opt_pass * | |
497 | make_pass_free_cfg (gcc::context *ctxt) | |
498 | { | |
499 | return new pass_free_cfg (ctxt); | |
500 | } | |
501 | ||
91278841 AP |
502 | /* Return RTX to emit after when we want to emit code on the entry of function. */ |
503 | rtx | |
504 | entry_of_function (void) | |
505 | { | |
0cae8d31 | 506 | return (n_basic_blocks_for_fn (cfun) > NUM_FIXED_BLOCKS ? |
fefa31b5 | 507 | BB_HEAD (ENTRY_BLOCK_PTR_FOR_FN (cfun)->next_bb) : get_insns ()); |
91278841 AP |
508 | } |
509 | ||
11b904a1 BS |
510 | /* Emit INSN at the entry point of the function, ensuring that it is only |
511 | executed once per function. */ | |
512 | void | |
513 | emit_insn_at_entry (rtx insn) | |
514 | { | |
fefa31b5 | 515 | edge_iterator ei = ei_start (ENTRY_BLOCK_PTR_FOR_FN (cfun)->succs); |
11b904a1 | 516 | edge e = ei_safe_edge (ei); |
5419bc7f | 517 | gcc_assert (e->flags & EDGE_FALLTHRU); |
11b904a1 BS |
518 | |
519 | insert_insn_on_edge (insn, e); | |
520 | commit_edge_insertions (); | |
521 | } | |
522 | ||
6c3d0e31 | 523 | /* Update BLOCK_FOR_INSN of insns between BEGIN and END |
b8698a0f | 524 | (or BARRIER if found) and notify df of the bb change. |
6c3d0e31 SP |
525 | The insn chain range is inclusive |
526 | (i.e. both BEGIN and END will be updated. */ | |
ca6c03ca | 527 | |
6c3d0e31 SP |
528 | static void |
529 | update_bb_for_insn_chain (rtx begin, rtx end, basic_block bb) | |
ca6c03ca JH |
530 | { |
531 | rtx insn; | |
532 | ||
6c3d0e31 SP |
533 | end = NEXT_INSN (end); |
534 | for (insn = begin; insn != end; insn = NEXT_INSN (insn)) | |
63642d5a AO |
535 | if (!BARRIER_P (insn)) |
536 | df_insn_change_bb (insn, bb); | |
ca6c03ca | 537 | } |
6c3d0e31 SP |
538 | |
539 | /* Update BLOCK_FOR_INSN of insns in BB to BB, | |
540 | and notify df of the change. */ | |
541 | ||
542 | void | |
543 | update_bb_for_insn (basic_block bb) | |
544 | { | |
545 | update_bb_for_insn_chain (BB_HEAD (bb), BB_END (bb), bb); | |
546 | } | |
547 | ||
532aafad SB |
548 | \f |
549 | /* Like active_insn_p, except keep the return value clobber around | |
550 | even after reload. */ | |
551 | ||
552 | static bool | |
553 | flow_active_insn_p (const_rtx insn) | |
554 | { | |
555 | if (active_insn_p (insn)) | |
556 | return true; | |
557 | ||
558 | /* A clobber of the function return value exists for buggy | |
559 | programs that fail to return a value. Its effect is to | |
560 | keep the return value from being live across the entire | |
561 | function. If we allow it to be skipped, we introduce the | |
562 | possibility for register lifetime confusion. */ | |
563 | if (GET_CODE (PATTERN (insn)) == CLOBBER | |
564 | && REG_P (XEXP (PATTERN (insn), 0)) | |
565 | && REG_FUNCTION_VALUE_P (XEXP (PATTERN (insn), 0))) | |
566 | return true; | |
567 | ||
568 | return false; | |
569 | } | |
570 | ||
571 | /* Return true if the block has no effect and only forwards control flow to | |
572 | its single destination. */ | |
532aafad SB |
573 | |
574 | bool | |
2407343c | 575 | contains_no_active_insn_p (const_basic_block bb) |
532aafad SB |
576 | { |
577 | rtx insn; | |
578 | ||
fefa31b5 | 579 | if (bb == EXIT_BLOCK_PTR_FOR_FN (cfun) || bb == ENTRY_BLOCK_PTR_FOR_FN (cfun) |
532aafad SB |
580 | || !single_succ_p (bb)) |
581 | return false; | |
582 | ||
2407343c JR |
583 | for (insn = BB_HEAD (bb); insn != BB_END (bb); insn = NEXT_INSN (insn)) |
584 | if (INSN_P (insn) && flow_active_insn_p (insn)) | |
585 | return false; | |
586 | ||
587 | return (!INSN_P (insn) | |
588 | || (JUMP_P (insn) && simplejump_p (insn)) | |
589 | || !flow_active_insn_p (insn)); | |
590 | } | |
591 | ||
592 | /* Likewise, but protect loop latches, headers and preheaders. */ | |
593 | /* FIXME: Make this a cfg hook. */ | |
594 | ||
595 | bool | |
596 | forwarder_block_p (const_basic_block bb) | |
597 | { | |
598 | if (!contains_no_active_insn_p (bb)) | |
599 | return false; | |
600 | ||
532aafad SB |
601 | /* Protect loop latches, headers and preheaders. */ |
602 | if (current_loops) | |
603 | { | |
604 | basic_block dest; | |
605 | if (bb->loop_father->header == bb) | |
606 | return false; | |
607 | dest = EDGE_SUCC (bb, 0)->dest; | |
608 | if (dest->loop_father->header == dest) | |
609 | return false; | |
610 | } | |
611 | ||
2407343c | 612 | return true; |
532aafad SB |
613 | } |
614 | ||
615 | /* Return nonzero if we can reach target from src by falling through. */ | |
d7b6661b | 616 | /* FIXME: Make this a cfg hook, the result is only valid in cfgrtl mode. */ |
532aafad SB |
617 | |
618 | bool | |
619 | can_fallthru (basic_block src, basic_block target) | |
620 | { | |
621 | rtx insn = BB_END (src); | |
622 | rtx insn2; | |
623 | edge e; | |
624 | edge_iterator ei; | |
625 | ||
fefa31b5 | 626 | if (target == EXIT_BLOCK_PTR_FOR_FN (cfun)) |
532aafad SB |
627 | return true; |
628 | if (src->next_bb != target) | |
d7b6661b SB |
629 | return false; |
630 | ||
631 | /* ??? Later we may add code to move jump tables offline. */ | |
632 | if (tablejump_p (insn, NULL, NULL)) | |
633 | return false; | |
634 | ||
532aafad | 635 | FOR_EACH_EDGE (e, ei, src->succs) |
fefa31b5 | 636 | if (e->dest == EXIT_BLOCK_PTR_FOR_FN (cfun) |
532aafad | 637 | && e->flags & EDGE_FALLTHRU) |
d7b6661b | 638 | return false; |
532aafad SB |
639 | |
640 | insn2 = BB_HEAD (target); | |
d7b6661b | 641 | if (!active_insn_p (insn2)) |
532aafad SB |
642 | insn2 = next_active_insn (insn2); |
643 | ||
532aafad SB |
644 | return next_active_insn (insn) == insn2; |
645 | } | |
646 | ||
647 | /* Return nonzero if we could reach target from src by falling through, | |
648 | if the target was made adjacent. If we already have a fall-through | |
649 | edge to the exit block, we can't do that. */ | |
650 | static bool | |
651 | could_fall_through (basic_block src, basic_block target) | |
652 | { | |
653 | edge e; | |
654 | edge_iterator ei; | |
655 | ||
fefa31b5 | 656 | if (target == EXIT_BLOCK_PTR_FOR_FN (cfun)) |
532aafad SB |
657 | return true; |
658 | FOR_EACH_EDGE (e, ei, src->succs) | |
fefa31b5 | 659 | if (e->dest == EXIT_BLOCK_PTR_FOR_FN (cfun) |
532aafad SB |
660 | && e->flags & EDGE_FALLTHRU) |
661 | return 0; | |
662 | return true; | |
663 | } | |
ca6c03ca | 664 | \f |
ef2be249 RS |
665 | /* Return the NOTE_INSN_BASIC_BLOCK of BB. */ |
666 | rtx | |
667 | bb_note (basic_block bb) | |
668 | { | |
669 | rtx note; | |
670 | ||
671 | note = BB_HEAD (bb); | |
672 | if (LABEL_P (note)) | |
673 | note = NEXT_INSN (note); | |
674 | ||
675 | gcc_assert (NOTE_INSN_BASIC_BLOCK_P (note)); | |
676 | return note; | |
677 | } | |
678 | ||
6fb5fa3c DB |
679 | /* Return the INSN immediately following the NOTE_INSN_BASIC_BLOCK |
680 | note associated with the BLOCK. */ | |
681 | ||
682 | static rtx | |
683 | first_insn_after_basic_block_note (basic_block block) | |
684 | { | |
685 | rtx insn; | |
686 | ||
687 | /* Get the first instruction in the block. */ | |
688 | insn = BB_HEAD (block); | |
689 | ||
690 | if (insn == NULL_RTX) | |
691 | return NULL_RTX; | |
692 | if (LABEL_P (insn)) | |
693 | insn = NEXT_INSN (insn); | |
694 | gcc_assert (NOTE_INSN_BASIC_BLOCK_P (insn)); | |
695 | ||
696 | return NEXT_INSN (insn); | |
697 | } | |
698 | ||
f470c378 ZD |
699 | /* Creates a new basic block just after basic block B by splitting |
700 | everything after specified instruction I. */ | |
ca6c03ca | 701 | |
f470c378 | 702 | static basic_block |
d329e058 | 703 | rtl_split_block (basic_block bb, void *insnp) |
ca6c03ca JH |
704 | { |
705 | basic_block new_bb; | |
ae50c0cb | 706 | rtx insn = (rtx) insnp; |
f470c378 | 707 | edge e; |
628f6a4e | 708 | edge_iterator ei; |
ca6c03ca | 709 | |
f470c378 ZD |
710 | if (!insn) |
711 | { | |
712 | insn = first_insn_after_basic_block_note (bb); | |
713 | ||
714 | if (insn) | |
b5b8b0ac AO |
715 | { |
716 | rtx next = insn; | |
717 | ||
718 | insn = PREV_INSN (insn); | |
719 | ||
720 | /* If the block contains only debug insns, insn would have | |
721 | been NULL in a non-debug compilation, and then we'd end | |
722 | up emitting a DELETED note. For -fcompare-debug | |
723 | stability, emit the note too. */ | |
724 | if (insn != BB_END (bb) | |
725 | && DEBUG_INSN_P (next) | |
726 | && DEBUG_INSN_P (BB_END (bb))) | |
727 | { | |
728 | while (next != BB_END (bb) && DEBUG_INSN_P (next)) | |
729 | next = NEXT_INSN (next); | |
730 | ||
731 | if (next == BB_END (bb)) | |
732 | emit_note_after (NOTE_INSN_DELETED, next); | |
733 | } | |
734 | } | |
f470c378 ZD |
735 | else |
736 | insn = get_last_insn (); | |
737 | } | |
738 | ||
739 | /* We probably should check type of the insn so that we do not create | |
740 | inconsistent cfg. It is checked in verify_flow_info anyway, so do not | |
741 | bother. */ | |
742 | if (insn == BB_END (bb)) | |
743 | emit_note_after (NOTE_INSN_DELETED, insn); | |
ca6c03ca JH |
744 | |
745 | /* Create the new basic block. */ | |
a813c111 | 746 | new_bb = create_basic_block (NEXT_INSN (insn), BB_END (bb), bb); |
076c7ab8 | 747 | BB_COPY_PARTITION (new_bb, bb); |
a813c111 | 748 | BB_END (bb) = insn; |
ca6c03ca JH |
749 | |
750 | /* Redirect the outgoing edges. */ | |
628f6a4e BE |
751 | new_bb->succs = bb->succs; |
752 | bb->succs = NULL; | |
753 | FOR_EACH_EDGE (e, ei, new_bb->succs) | |
ca6c03ca JH |
754 | e->src = new_bb; |
755 | ||
6fb5fa3c DB |
756 | /* The new block starts off being dirty. */ |
757 | df_set_bb_dirty (bb); | |
f470c378 | 758 | return new_bb; |
bc35512f JH |
759 | } |
760 | ||
9be94227 EB |
761 | /* Return true if the single edge between blocks A and B is the only place |
762 | in RTL which holds some unique locus. */ | |
763 | ||
764 | static bool | |
765 | unique_locus_on_edge_between_p (basic_block a, basic_block b) | |
766 | { | |
5368224f | 767 | const location_t goto_locus = EDGE_SUCC (a, 0)->goto_locus; |
9be94227 EB |
768 | rtx insn, end; |
769 | ||
2f13f2de | 770 | if (LOCATION_LOCUS (goto_locus) == UNKNOWN_LOCATION) |
9be94227 EB |
771 | return false; |
772 | ||
773 | /* First scan block A backward. */ | |
774 | insn = BB_END (a); | |
775 | end = PREV_INSN (BB_HEAD (a)); | |
5368224f | 776 | while (insn != end && (!NONDEBUG_INSN_P (insn) || !INSN_HAS_LOCATION (insn))) |
9be94227 EB |
777 | insn = PREV_INSN (insn); |
778 | ||
5368224f | 779 | if (insn != end && INSN_LOCATION (insn) == goto_locus) |
9be94227 EB |
780 | return false; |
781 | ||
782 | /* Then scan block B forward. */ | |
783 | insn = BB_HEAD (b); | |
784 | if (insn) | |
785 | { | |
786 | end = NEXT_INSN (BB_END (b)); | |
787 | while (insn != end && !NONDEBUG_INSN_P (insn)) | |
788 | insn = NEXT_INSN (insn); | |
789 | ||
5368224f DC |
790 | if (insn != end && INSN_HAS_LOCATION (insn) |
791 | && INSN_LOCATION (insn) == goto_locus) | |
9be94227 EB |
792 | return false; |
793 | } | |
794 | ||
795 | return true; | |
796 | } | |
797 | ||
798 | /* If the single edge between blocks A and B is the only place in RTL which | |
799 | holds some unique locus, emit a nop with that locus between the blocks. */ | |
800 | ||
801 | static void | |
802 | emit_nop_for_unique_locus_between (basic_block a, basic_block b) | |
803 | { | |
804 | if (!unique_locus_on_edge_between_p (a, b)) | |
805 | return; | |
806 | ||
807 | BB_END (a) = emit_insn_after_noloc (gen_nop (), BB_END (a), a); | |
5368224f | 808 | INSN_LOCATION (BB_END (a)) = EDGE_SUCC (a, 0)->goto_locus; |
9be94227 EB |
809 | } |
810 | ||
ca6c03ca | 811 | /* Blocks A and B are to be merged into a single block A. The insns |
bc35512f | 812 | are already contiguous. */ |
ca6c03ca | 813 | |
bc35512f JH |
814 | static void |
815 | rtl_merge_blocks (basic_block a, basic_block b) | |
ca6c03ca | 816 | { |
a813c111 | 817 | rtx b_head = BB_HEAD (b), b_end = BB_END (b), a_end = BB_END (a); |
ca6c03ca | 818 | rtx del_first = NULL_RTX, del_last = NULL_RTX; |
b5b8b0ac | 819 | rtx b_debug_start = b_end, b_debug_end = b_end; |
50a36e42 | 820 | bool forwarder_p = (b->flags & BB_FORWARDER_BLOCK) != 0; |
ca6c03ca JH |
821 | int b_empty = 0; |
822 | ||
6fb5fa3c | 823 | if (dump_file) |
50a36e42 EB |
824 | fprintf (dump_file, "Merging block %d into block %d...\n", b->index, |
825 | a->index); | |
6fb5fa3c | 826 | |
b5b8b0ac AO |
827 | while (DEBUG_INSN_P (b_end)) |
828 | b_end = PREV_INSN (b_debug_start = b_end); | |
829 | ||
ca6c03ca | 830 | /* If there was a CODE_LABEL beginning B, delete it. */ |
4b4bf941 | 831 | if (LABEL_P (b_head)) |
ca6c03ca JH |
832 | { |
833 | /* Detect basic blocks with nothing but a label. This can happen | |
834 | in particular at the end of a function. */ | |
835 | if (b_head == b_end) | |
836 | b_empty = 1; | |
5f0d2358 | 837 | |
ca6c03ca JH |
838 | del_first = del_last = b_head; |
839 | b_head = NEXT_INSN (b_head); | |
840 | } | |
841 | ||
5f0d2358 RK |
842 | /* Delete the basic block note and handle blocks containing just that |
843 | note. */ | |
ca6c03ca JH |
844 | if (NOTE_INSN_BASIC_BLOCK_P (b_head)) |
845 | { | |
846 | if (b_head == b_end) | |
847 | b_empty = 1; | |
848 | if (! del_last) | |
849 | del_first = b_head; | |
5f0d2358 | 850 | |
ca6c03ca JH |
851 | del_last = b_head; |
852 | b_head = NEXT_INSN (b_head); | |
853 | } | |
854 | ||
855 | /* If there was a jump out of A, delete it. */ | |
4b4bf941 | 856 | if (JUMP_P (a_end)) |
ca6c03ca JH |
857 | { |
858 | rtx prev; | |
859 | ||
860 | for (prev = PREV_INSN (a_end); ; prev = PREV_INSN (prev)) | |
4b4bf941 | 861 | if (!NOTE_P (prev) |
a38e7aa5 | 862 | || NOTE_INSN_BASIC_BLOCK_P (prev) |
a813c111 | 863 | || prev == BB_HEAD (a)) |
ca6c03ca JH |
864 | break; |
865 | ||
866 | del_first = a_end; | |
867 | ||
868 | #ifdef HAVE_cc0 | |
869 | /* If this was a conditional jump, we need to also delete | |
870 | the insn that set cc0. */ | |
871 | if (only_sets_cc0_p (prev)) | |
872 | { | |
873 | rtx tmp = prev; | |
5f0d2358 | 874 | |
ca6c03ca JH |
875 | prev = prev_nonnote_insn (prev); |
876 | if (!prev) | |
a813c111 | 877 | prev = BB_HEAD (a); |
ca6c03ca JH |
878 | del_first = tmp; |
879 | } | |
880 | #endif | |
881 | ||
882 | a_end = PREV_INSN (del_first); | |
883 | } | |
4b4bf941 | 884 | else if (BARRIER_P (NEXT_INSN (a_end))) |
ca6c03ca JH |
885 | del_first = NEXT_INSN (a_end); |
886 | ||
ca6c03ca JH |
887 | /* Delete everything marked above as well as crap that might be |
888 | hanging out between the two blocks. */ | |
9be94227 EB |
889 | BB_END (a) = a_end; |
890 | BB_HEAD (b) = b_empty ? NULL_RTX : b_head; | |
a7b87f73 | 891 | delete_insn_chain (del_first, del_last, true); |
ca6c03ca | 892 | |
9be94227 EB |
893 | /* When not optimizing CFG and the edge is the only place in RTL which holds |
894 | some unique locus, emit a nop with that locus in between. */ | |
895 | if (!optimize) | |
896 | { | |
897 | emit_nop_for_unique_locus_between (a, b); | |
898 | a_end = BB_END (a); | |
899 | } | |
900 | ||
ca6c03ca JH |
901 | /* Reassociate the insns of B with A. */ |
902 | if (!b_empty) | |
903 | { | |
b5b8b0ac | 904 | update_bb_for_insn_chain (a_end, b_debug_end, a); |
5f0d2358 | 905 | |
9be94227 EB |
906 | BB_END (a) = b_debug_end; |
907 | BB_HEAD (b) = NULL_RTX; | |
b5b8b0ac AO |
908 | } |
909 | else if (b_end != b_debug_end) | |
910 | { | |
911 | /* Move any deleted labels and other notes between the end of A | |
912 | and the debug insns that make up B after the debug insns, | |
913 | bringing the debug insns into A while keeping the notes after | |
914 | the end of A. */ | |
915 | if (NEXT_INSN (a_end) != b_debug_start) | |
916 | reorder_insns_nobb (NEXT_INSN (a_end), PREV_INSN (b_debug_start), | |
917 | b_debug_end); | |
918 | update_bb_for_insn_chain (b_debug_start, b_debug_end, a); | |
9be94227 | 919 | BB_END (a) = b_debug_end; |
ca6c03ca | 920 | } |
5f0d2358 | 921 | |
6fb5fa3c | 922 | df_bb_delete (b->index); |
50a36e42 EB |
923 | |
924 | /* If B was a forwarder block, propagate the locus on the edge. */ | |
fbc68f2a DC |
925 | if (forwarder_p |
926 | && LOCATION_LOCUS (EDGE_SUCC (b, 0)->goto_locus) == UNKNOWN_LOCATION) | |
50a36e42 EB |
927 | EDGE_SUCC (b, 0)->goto_locus = EDGE_SUCC (a, 0)->goto_locus; |
928 | ||
929 | if (dump_file) | |
930 | fprintf (dump_file, "Merged blocks %d and %d.\n", a->index, b->index); | |
ca6c03ca | 931 | } |
bc35512f | 932 | |
6fb5fa3c | 933 | |
bc35512f | 934 | /* Return true when block A and B can be merged. */ |
9678086d | 935 | |
b48d0358 DN |
936 | static bool |
937 | rtl_can_merge_blocks (basic_block a, basic_block b) | |
bc35512f | 938 | { |
750054a2 CT |
939 | /* If we are partitioning hot/cold basic blocks, we don't want to |
940 | mess up unconditional or indirect jumps that cross between hot | |
076c7ab8 ZW |
941 | and cold sections. |
942 | ||
8e8d5162 | 943 | Basic block partitioning may result in some jumps that appear to |
c22cacf3 MS |
944 | be optimizable (or blocks that appear to be mergeable), but which really |
945 | must be left untouched (they are required to make it safely across | |
946 | partition boundaries). See the comments at the top of | |
8e8d5162 | 947 | bb-reorder.c:partition_hot_cold_basic_blocks for complete details. */ |
076c7ab8 | 948 | |
87c8b4be | 949 | if (BB_PARTITION (a) != BB_PARTITION (b)) |
076c7ab8 | 950 | return false; |
750054a2 | 951 | |
7d776ee2 RG |
952 | /* Protect the loop latches. */ |
953 | if (current_loops && b->loop_father->latch == b) | |
954 | return false; | |
955 | ||
bc35512f | 956 | /* There must be exactly one edge in between the blocks. */ |
c5cbcccf ZD |
957 | return (single_succ_p (a) |
958 | && single_succ (a) == b | |
959 | && single_pred_p (b) | |
628f6a4e | 960 | && a != b |
bc35512f | 961 | /* Must be simple edge. */ |
c5cbcccf | 962 | && !(single_succ_edge (a)->flags & EDGE_COMPLEX) |
bc35512f | 963 | && a->next_bb == b |
fefa31b5 DM |
964 | && a != ENTRY_BLOCK_PTR_FOR_FN (cfun) |
965 | && b != EXIT_BLOCK_PTR_FOR_FN (cfun) | |
bc35512f JH |
966 | /* If the jump insn has side effects, |
967 | we can't kill the edge. */ | |
4b4bf941 | 968 | && (!JUMP_P (BB_END (a)) |
e24e7211 | 969 | || (reload_completed |
a813c111 | 970 | ? simplejump_p (BB_END (a)) : onlyjump_p (BB_END (a))))); |
bc35512f | 971 | } |
ca6c03ca | 972 | \f |
5f0d2358 RK |
973 | /* Return the label in the head of basic block BLOCK. Create one if it doesn't |
974 | exist. */ | |
ca6c03ca JH |
975 | |
976 | rtx | |
d329e058 | 977 | block_label (basic_block block) |
ca6c03ca | 978 | { |
fefa31b5 | 979 | if (block == EXIT_BLOCK_PTR_FOR_FN (cfun)) |
ca6c03ca | 980 | return NULL_RTX; |
5f0d2358 | 981 | |
4b4bf941 | 982 | if (!LABEL_P (BB_HEAD (block))) |
ca6c03ca | 983 | { |
a813c111 | 984 | BB_HEAD (block) = emit_label_before (gen_label_rtx (), BB_HEAD (block)); |
ca6c03ca | 985 | } |
5f0d2358 | 986 | |
a813c111 | 987 | return BB_HEAD (block); |
ca6c03ca JH |
988 | } |
989 | ||
990 | /* Attempt to perform edge redirection by replacing possibly complex jump | |
5f0d2358 RK |
991 | instruction by unconditional jump or removing jump completely. This can |
992 | apply only if all edges now point to the same block. The parameters and | |
993 | return values are equivalent to redirect_edge_and_branch. */ | |
ca6c03ca | 994 | |
6de9cd9a | 995 | edge |
bc35512f | 996 | try_redirect_by_replacing_jump (edge e, basic_block target, bool in_cfglayout) |
ca6c03ca JH |
997 | { |
998 | basic_block src = e->src; | |
a813c111 | 999 | rtx insn = BB_END (src), kill_from; |
e1233a7d | 1000 | rtx set; |
ca6c03ca | 1001 | int fallthru = 0; |
750054a2 CT |
1002 | |
1003 | /* If we are partitioning hot/cold basic blocks, we don't want to | |
1004 | mess up unconditional or indirect jumps that cross between hot | |
8e8d5162 CT |
1005 | and cold sections. |
1006 | ||
1007 | Basic block partitioning may result in some jumps that appear to | |
c22cacf3 MS |
1008 | be optimizable (or blocks that appear to be mergeable), but which really |
1009 | must be left untouched (they are required to make it safely across | |
1010 | partition boundaries). See the comments at the top of | |
8e8d5162 | 1011 | bb-reorder.c:partition_hot_cold_basic_blocks for complete details. */ |
c22cacf3 | 1012 | |
3371a64f | 1013 | if (BB_PARTITION (src) != BB_PARTITION (target)) |
9cf84a3c | 1014 | return NULL; |
750054a2 | 1015 | |
6a66a8a7 KH |
1016 | /* We can replace or remove a complex jump only when we have exactly |
1017 | two edges. Also, if we have exactly one outgoing edge, we can | |
1018 | redirect that. */ | |
1019 | if (EDGE_COUNT (src->succs) >= 3 | |
1020 | /* Verify that all targets will be TARGET. Specifically, the | |
1021 | edge that is not E must also go to TARGET. */ | |
1022 | || (EDGE_COUNT (src->succs) == 2 | |
1023 | && EDGE_SUCC (src, EDGE_SUCC (src, 0) == e)->dest != target)) | |
1024 | return NULL; | |
5f0d2358 | 1025 | |
6a66a8a7 | 1026 | if (!onlyjump_p (insn)) |
6de9cd9a | 1027 | return NULL; |
3348b696 | 1028 | if ((!optimize || reload_completed) && tablejump_p (insn, NULL, NULL)) |
6de9cd9a | 1029 | return NULL; |
ca6c03ca JH |
1030 | |
1031 | /* Avoid removing branch with side effects. */ | |
1032 | set = single_set (insn); | |
1033 | if (!set || side_effects_p (set)) | |
6de9cd9a | 1034 | return NULL; |
ca6c03ca JH |
1035 | |
1036 | /* In case we zap a conditional jump, we'll need to kill | |
1037 | the cc0 setter too. */ | |
1038 | kill_from = insn; | |
1039 | #ifdef HAVE_cc0 | |
9caea4a7 RS |
1040 | if (reg_mentioned_p (cc0_rtx, PATTERN (insn)) |
1041 | && only_sets_cc0_p (PREV_INSN (insn))) | |
ca6c03ca JH |
1042 | kill_from = PREV_INSN (insn); |
1043 | #endif | |
1044 | ||
1045 | /* See if we can create the fallthru edge. */ | |
bc35512f | 1046 | if (in_cfglayout || can_fallthru (src, target)) |
ca6c03ca | 1047 | { |
c263766c RH |
1048 | if (dump_file) |
1049 | fprintf (dump_file, "Removing jump %i.\n", INSN_UID (insn)); | |
ca6c03ca JH |
1050 | fallthru = 1; |
1051 | ||
eaec9b3d | 1052 | /* Selectively unlink whole insn chain. */ |
bc35512f JH |
1053 | if (in_cfglayout) |
1054 | { | |
bcc708fc | 1055 | rtx insn = BB_FOOTER (src); |
bc35512f | 1056 | |
a7b87f73 | 1057 | delete_insn_chain (kill_from, BB_END (src), false); |
bc35512f JH |
1058 | |
1059 | /* Remove barriers but keep jumptables. */ | |
1060 | while (insn) | |
1061 | { | |
4b4bf941 | 1062 | if (BARRIER_P (insn)) |
bc35512f JH |
1063 | { |
1064 | if (PREV_INSN (insn)) | |
1065 | NEXT_INSN (PREV_INSN (insn)) = NEXT_INSN (insn); | |
1066 | else | |
bcc708fc | 1067 | BB_FOOTER (src) = NEXT_INSN (insn); |
bc35512f JH |
1068 | if (NEXT_INSN (insn)) |
1069 | PREV_INSN (NEXT_INSN (insn)) = PREV_INSN (insn); | |
1070 | } | |
4b4bf941 | 1071 | if (LABEL_P (insn)) |
bc35512f JH |
1072 | break; |
1073 | insn = NEXT_INSN (insn); | |
1074 | } | |
1075 | } | |
1076 | else | |
a7b87f73 ZD |
1077 | delete_insn_chain (kill_from, PREV_INSN (BB_HEAD (target)), |
1078 | false); | |
ca6c03ca | 1079 | } |
5f0d2358 | 1080 | |
ca6c03ca JH |
1081 | /* If this already is simplejump, redirect it. */ |
1082 | else if (simplejump_p (insn)) | |
1083 | { | |
1084 | if (e->dest == target) | |
6de9cd9a | 1085 | return NULL; |
c263766c RH |
1086 | if (dump_file) |
1087 | fprintf (dump_file, "Redirecting jump %i from %i to %i.\n", | |
0b17ab2f | 1088 | INSN_UID (insn), e->dest->index, target->index); |
6ee3c8e4 JJ |
1089 | if (!redirect_jump (insn, block_label (target), 0)) |
1090 | { | |
fefa31b5 | 1091 | gcc_assert (target == EXIT_BLOCK_PTR_FOR_FN (cfun)); |
341c100f | 1092 | return NULL; |
6ee3c8e4 | 1093 | } |
ca6c03ca | 1094 | } |
5f0d2358 | 1095 | |
6ee3c8e4 | 1096 | /* Cannot do anything for target exit block. */ |
fefa31b5 | 1097 | else if (target == EXIT_BLOCK_PTR_FOR_FN (cfun)) |
6de9cd9a | 1098 | return NULL; |
6ee3c8e4 | 1099 | |
ca6c03ca JH |
1100 | /* Or replace possibly complicated jump insn by simple jump insn. */ |
1101 | else | |
1102 | { | |
1103 | rtx target_label = block_label (target); | |
eb5b8ad4 | 1104 | rtx barrier, label, table; |
ca6c03ca | 1105 | |
a7102479 | 1106 | emit_jump_insn_after_noloc (gen_jump (target_label), insn); |
a813c111 | 1107 | JUMP_LABEL (BB_END (src)) = target_label; |
ca6c03ca | 1108 | LABEL_NUSES (target_label)++; |
c263766c RH |
1109 | if (dump_file) |
1110 | fprintf (dump_file, "Replacing insn %i by jump %i\n", | |
a813c111 | 1111 | INSN_UID (insn), INSN_UID (BB_END (src))); |
ca6c03ca | 1112 | |
4da2eb6b | 1113 | |
ba4807a0 LB |
1114 | delete_insn_chain (kill_from, insn, false); |
1115 | ||
4da2eb6b RH |
1116 | /* Recognize a tablejump that we are converting to a |
1117 | simple jump and remove its associated CODE_LABEL | |
1118 | and ADDR_VEC or ADDR_DIFF_VEC. */ | |
ba4807a0 LB |
1119 | if (tablejump_p (insn, &label, &table)) |
1120 | delete_insn_chain (label, table, false); | |
eb5b8ad4 | 1121 | |
a813c111 | 1122 | barrier = next_nonnote_insn (BB_END (src)); |
4b4bf941 | 1123 | if (!barrier || !BARRIER_P (barrier)) |
a813c111 | 1124 | emit_barrier_after (BB_END (src)); |
5d693491 JZ |
1125 | else |
1126 | { | |
a813c111 | 1127 | if (barrier != NEXT_INSN (BB_END (src))) |
5d693491 JZ |
1128 | { |
1129 | /* Move the jump before barrier so that the notes | |
1130 | which originally were or were created before jump table are | |
1131 | inside the basic block. */ | |
a813c111 | 1132 | rtx new_insn = BB_END (src); |
5d693491 | 1133 | |
6c3d0e31 SP |
1134 | update_bb_for_insn_chain (NEXT_INSN (BB_END (src)), |
1135 | PREV_INSN (barrier), src); | |
5d693491 JZ |
1136 | |
1137 | NEXT_INSN (PREV_INSN (new_insn)) = NEXT_INSN (new_insn); | |
1138 | PREV_INSN (NEXT_INSN (new_insn)) = PREV_INSN (new_insn); | |
1139 | ||
1140 | NEXT_INSN (new_insn) = barrier; | |
1141 | NEXT_INSN (PREV_INSN (barrier)) = new_insn; | |
1142 | ||
1143 | PREV_INSN (new_insn) = PREV_INSN (barrier); | |
1144 | PREV_INSN (barrier) = new_insn; | |
1145 | } | |
1146 | } | |
ca6c03ca JH |
1147 | } |
1148 | ||
1149 | /* Keep only one edge out and set proper flags. */ | |
c5cbcccf | 1150 | if (!single_succ_p (src)) |
628f6a4e | 1151 | remove_edge (e); |
c5cbcccf | 1152 | gcc_assert (single_succ_p (src)); |
628f6a4e | 1153 | |
c5cbcccf | 1154 | e = single_succ_edge (src); |
ca6c03ca JH |
1155 | if (fallthru) |
1156 | e->flags = EDGE_FALLTHRU; | |
1157 | else | |
1158 | e->flags = 0; | |
5f0d2358 | 1159 | |
ca6c03ca JH |
1160 | e->probability = REG_BR_PROB_BASE; |
1161 | e->count = src->count; | |
1162 | ||
ca6c03ca JH |
1163 | if (e->dest != target) |
1164 | redirect_edge_succ (e, target); | |
6de9cd9a | 1165 | return e; |
ca6c03ca JH |
1166 | } |
1167 | ||
4e3825db MM |
1168 | /* Subroutine of redirect_branch_edge that tries to patch the jump |
1169 | instruction INSN so that it reaches block NEW. Do this | |
1170 | only when it originally reached block OLD. Return true if this | |
1171 | worked or the original target wasn't OLD, return false if redirection | |
1172 | doesn't work. */ | |
1173 | ||
1174 | static bool | |
1175 | patch_jump_insn (rtx insn, rtx old_label, basic_block new_bb) | |
ca6c03ca JH |
1176 | { |
1177 | rtx tmp; | |
ca6c03ca | 1178 | /* Recognize a tablejump and adjust all matching cases. */ |
e1233a7d | 1179 | if (tablejump_p (insn, NULL, &tmp)) |
ca6c03ca JH |
1180 | { |
1181 | rtvec vec; | |
1182 | int j; | |
4e3825db | 1183 | rtx new_label = block_label (new_bb); |
ca6c03ca | 1184 | |
fefa31b5 | 1185 | if (new_bb == EXIT_BLOCK_PTR_FOR_FN (cfun)) |
4e3825db | 1186 | return false; |
ca6c03ca JH |
1187 | if (GET_CODE (PATTERN (tmp)) == ADDR_VEC) |
1188 | vec = XVEC (PATTERN (tmp), 0); | |
1189 | else | |
1190 | vec = XVEC (PATTERN (tmp), 1); | |
1191 | ||
1192 | for (j = GET_NUM_ELEM (vec) - 1; j >= 0; --j) | |
1193 | if (XEXP (RTVEC_ELT (vec, j), 0) == old_label) | |
1194 | { | |
1195 | RTVEC_ELT (vec, j) = gen_rtx_LABEL_REF (Pmode, new_label); | |
1196 | --LABEL_NUSES (old_label); | |
1197 | ++LABEL_NUSES (new_label); | |
1198 | } | |
1199 | ||
f9da5064 | 1200 | /* Handle casesi dispatch insns. */ |
ca6c03ca JH |
1201 | if ((tmp = single_set (insn)) != NULL |
1202 | && SET_DEST (tmp) == pc_rtx | |
1203 | && GET_CODE (SET_SRC (tmp)) == IF_THEN_ELSE | |
1204 | && GET_CODE (XEXP (SET_SRC (tmp), 2)) == LABEL_REF | |
1205 | && XEXP (XEXP (SET_SRC (tmp), 2), 0) == old_label) | |
1206 | { | |
4c33cb26 | 1207 | XEXP (SET_SRC (tmp), 2) = gen_rtx_LABEL_REF (Pmode, |
ca6c03ca JH |
1208 | new_label); |
1209 | --LABEL_NUSES (old_label); | |
1210 | ++LABEL_NUSES (new_label); | |
1211 | } | |
1212 | } | |
1c384bf1 RH |
1213 | else if ((tmp = extract_asm_operands (PATTERN (insn))) != NULL) |
1214 | { | |
1215 | int i, n = ASM_OPERANDS_LABEL_LENGTH (tmp); | |
1216 | rtx new_label, note; | |
1217 | ||
fefa31b5 | 1218 | if (new_bb == EXIT_BLOCK_PTR_FOR_FN (cfun)) |
1c384bf1 RH |
1219 | return false; |
1220 | new_label = block_label (new_bb); | |
1221 | ||
1222 | for (i = 0; i < n; ++i) | |
1223 | { | |
1224 | rtx old_ref = ASM_OPERANDS_LABEL (tmp, i); | |
1225 | gcc_assert (GET_CODE (old_ref) == LABEL_REF); | |
1226 | if (XEXP (old_ref, 0) == old_label) | |
1227 | { | |
1228 | ASM_OPERANDS_LABEL (tmp, i) | |
1229 | = gen_rtx_LABEL_REF (Pmode, new_label); | |
1230 | --LABEL_NUSES (old_label); | |
1231 | ++LABEL_NUSES (new_label); | |
1232 | } | |
1233 | } | |
1234 | ||
1235 | if (JUMP_LABEL (insn) == old_label) | |
1236 | { | |
1237 | JUMP_LABEL (insn) = new_label; | |
1238 | note = find_reg_note (insn, REG_LABEL_TARGET, new_label); | |
1239 | if (note) | |
1240 | remove_note (insn, note); | |
1241 | } | |
1242 | else | |
1243 | { | |
1244 | note = find_reg_note (insn, REG_LABEL_TARGET, old_label); | |
1245 | if (note) | |
1246 | remove_note (insn, note); | |
1247 | if (JUMP_LABEL (insn) != new_label | |
1248 | && !find_reg_note (insn, REG_LABEL_TARGET, new_label)) | |
1249 | add_reg_note (insn, REG_LABEL_TARGET, new_label); | |
1250 | } | |
3b5fda81 JJ |
1251 | while ((note = find_reg_note (insn, REG_LABEL_OPERAND, old_label)) |
1252 | != NULL_RTX) | |
1253 | XEXP (note, 0) = new_label; | |
1c384bf1 | 1254 | } |
ca6c03ca JH |
1255 | else |
1256 | { | |
1257 | /* ?? We may play the games with moving the named labels from | |
1258 | one basic block to the other in case only one computed_jump is | |
1259 | available. */ | |
5f0d2358 RK |
1260 | if (computed_jump_p (insn) |
1261 | /* A return instruction can't be redirected. */ | |
1262 | || returnjump_p (insn)) | |
4e3825db | 1263 | return false; |
6ee3c8e4 | 1264 | |
4e3825db | 1265 | if (!currently_expanding_to_rtl || JUMP_LABEL (insn) == old_label) |
6ee3c8e4 | 1266 | { |
4e3825db MM |
1267 | /* If the insn doesn't go where we think, we're confused. */ |
1268 | gcc_assert (JUMP_LABEL (insn) == old_label); | |
1269 | ||
1270 | /* If the substitution doesn't succeed, die. This can happen | |
1271 | if the back end emitted unrecognizable instructions or if | |
1272 | target is exit block on some arches. */ | |
1273 | if (!redirect_jump (insn, block_label (new_bb), 0)) | |
1274 | { | |
fefa31b5 | 1275 | gcc_assert (new_bb == EXIT_BLOCK_PTR_FOR_FN (cfun)); |
4e3825db MM |
1276 | return false; |
1277 | } | |
6ee3c8e4 | 1278 | } |
ca6c03ca | 1279 | } |
4e3825db MM |
1280 | return true; |
1281 | } | |
1282 | ||
1283 | ||
1284 | /* Redirect edge representing branch of (un)conditional jump or tablejump, | |
1285 | NULL on failure */ | |
1286 | static edge | |
1287 | redirect_branch_edge (edge e, basic_block target) | |
1288 | { | |
1289 | rtx old_label = BB_HEAD (e->dest); | |
1290 | basic_block src = e->src; | |
1291 | rtx insn = BB_END (src); | |
1292 | ||
1293 | /* We can only redirect non-fallthru edges of jump insn. */ | |
1294 | if (e->flags & EDGE_FALLTHRU) | |
1295 | return NULL; | |
1296 | else if (!JUMP_P (insn) && !currently_expanding_to_rtl) | |
1297 | return NULL; | |
1298 | ||
1299 | if (!currently_expanding_to_rtl) | |
1300 | { | |
1301 | if (!patch_jump_insn (insn, old_label, target)) | |
1302 | return NULL; | |
1303 | } | |
1304 | else | |
1305 | /* When expanding this BB might actually contain multiple | |
1306 | jumps (i.e. not yet split by find_many_sub_basic_blocks). | |
1307 | Redirect all of those that match our label. */ | |
0f346928 | 1308 | FOR_BB_INSNS (src, insn) |
4e3825db MM |
1309 | if (JUMP_P (insn) && !patch_jump_insn (insn, old_label, target)) |
1310 | return NULL; | |
ca6c03ca | 1311 | |
c263766c RH |
1312 | if (dump_file) |
1313 | fprintf (dump_file, "Edge %i->%i redirected to %i\n", | |
0b17ab2f | 1314 | e->src->index, e->dest->index, target->index); |
5f0d2358 | 1315 | |
ca6c03ca | 1316 | if (e->dest != target) |
6de9cd9a | 1317 | e = redirect_edge_succ_nodup (e, target); |
6fb5fa3c | 1318 | |
6de9cd9a | 1319 | return e; |
bc35512f JH |
1320 | } |
1321 | ||
3371a64f TJ |
1322 | /* Called when edge E has been redirected to a new destination, |
1323 | in order to update the region crossing flag on the edge and | |
1324 | jump. */ | |
1325 | ||
1326 | static void | |
1327 | fixup_partition_crossing (edge e) | |
1328 | { | |
1329 | rtx note; | |
1330 | ||
fefa31b5 DM |
1331 | if (e->src == ENTRY_BLOCK_PTR_FOR_FN (cfun) || e->dest |
1332 | == EXIT_BLOCK_PTR_FOR_FN (cfun)) | |
3371a64f TJ |
1333 | return; |
1334 | /* If we redirected an existing edge, it may already be marked | |
1335 | crossing, even though the new src is missing a reg crossing note. | |
1336 | But make sure reg crossing note doesn't already exist before | |
1337 | inserting. */ | |
1338 | if (BB_PARTITION (e->src) != BB_PARTITION (e->dest)) | |
1339 | { | |
1340 | e->flags |= EDGE_CROSSING; | |
1341 | note = find_reg_note (BB_END (e->src), REG_CROSSING_JUMP, NULL_RTX); | |
1342 | if (JUMP_P (BB_END (e->src)) | |
1343 | && !note) | |
1344 | add_reg_note (BB_END (e->src), REG_CROSSING_JUMP, NULL_RTX); | |
1345 | } | |
1346 | else if (BB_PARTITION (e->src) == BB_PARTITION (e->dest)) | |
1347 | { | |
1348 | e->flags &= ~EDGE_CROSSING; | |
1349 | /* Remove the section crossing note from jump at end of | |
1350 | src if it exists, and if no other successors are | |
1351 | still crossing. */ | |
1352 | note = find_reg_note (BB_END (e->src), REG_CROSSING_JUMP, NULL_RTX); | |
1353 | if (note) | |
1354 | { | |
1355 | bool has_crossing_succ = false; | |
1356 | edge e2; | |
1357 | edge_iterator ei; | |
1358 | FOR_EACH_EDGE (e2, ei, e->src->succs) | |
1359 | { | |
1360 | has_crossing_succ |= (e2->flags & EDGE_CROSSING); | |
1361 | if (has_crossing_succ) | |
1362 | break; | |
1363 | } | |
1364 | if (!has_crossing_succ) | |
1365 | remove_note (BB_END (e->src), note); | |
1366 | } | |
1367 | } | |
1368 | } | |
1369 | ||
600b5b1d TJ |
1370 | /* Called when block BB has been reassigned to the cold partition, |
1371 | because it is now dominated by another cold block, | |
1372 | to ensure that the region crossing attributes are updated. */ | |
1373 | ||
1374 | static void | |
1375 | fixup_new_cold_bb (basic_block bb) | |
1376 | { | |
1377 | edge e; | |
1378 | edge_iterator ei; | |
1379 | ||
1380 | /* This is called when a hot bb is found to now be dominated | |
1381 | by a cold bb and therefore needs to become cold. Therefore, | |
1382 | its preds will no longer be region crossing. Any non-dominating | |
1383 | preds that were previously hot would also have become cold | |
1384 | in the caller for the same region. Any preds that were previously | |
1385 | region-crossing will be adjusted in fixup_partition_crossing. */ | |
1386 | FOR_EACH_EDGE (e, ei, bb->preds) | |
1387 | { | |
1388 | fixup_partition_crossing (e); | |
1389 | } | |
1390 | ||
1391 | /* Possibly need to make bb's successor edges region crossing, | |
1392 | or remove stale region crossing. */ | |
1393 | FOR_EACH_EDGE (e, ei, bb->succs) | |
1394 | { | |
1395 | /* We can't have fall-through edges across partition boundaries. | |
1396 | Note that force_nonfallthru will do any necessary partition | |
1397 | boundary fixup by calling fixup_partition_crossing itself. */ | |
1398 | if ((e->flags & EDGE_FALLTHRU) | |
1399 | && BB_PARTITION (bb) != BB_PARTITION (e->dest) | |
fefa31b5 | 1400 | && e->dest != EXIT_BLOCK_PTR_FOR_FN (cfun)) |
600b5b1d TJ |
1401 | force_nonfallthru (e); |
1402 | else | |
1403 | fixup_partition_crossing (e); | |
1404 | } | |
1405 | } | |
1406 | ||
bc35512f JH |
1407 | /* Attempt to change code to redirect edge E to TARGET. Don't do that on |
1408 | expense of adding new instructions or reordering basic blocks. | |
1409 | ||
1410 | Function can be also called with edge destination equivalent to the TARGET. | |
1411 | Then it should try the simplifications and do nothing if none is possible. | |
1412 | ||
6de9cd9a DN |
1413 | Return edge representing the branch if transformation succeeded. Return NULL |
1414 | on failure. | |
1415 | We still return NULL in case E already destinated TARGET and we didn't | |
1416 | managed to simplify instruction stream. */ | |
bc35512f | 1417 | |
6de9cd9a | 1418 | static edge |
5671bf27 | 1419 | rtl_redirect_edge_and_branch (edge e, basic_block target) |
bc35512f | 1420 | { |
6de9cd9a | 1421 | edge ret; |
f345f21a | 1422 | basic_block src = e->src; |
3371a64f | 1423 | basic_block dest = e->dest; |
f345f21a | 1424 | |
bc35512f | 1425 | if (e->flags & (EDGE_ABNORMAL_CALL | EDGE_EH)) |
6de9cd9a | 1426 | return NULL; |
bc35512f | 1427 | |
3371a64f | 1428 | if (dest == target) |
6de9cd9a | 1429 | return e; |
3348b696 | 1430 | |
6de9cd9a | 1431 | if ((ret = try_redirect_by_replacing_jump (e, target, false)) != NULL) |
f345f21a | 1432 | { |
6fb5fa3c | 1433 | df_set_bb_dirty (src); |
3371a64f | 1434 | fixup_partition_crossing (ret); |
6de9cd9a | 1435 | return ret; |
f345f21a | 1436 | } |
bc35512f | 1437 | |
6de9cd9a DN |
1438 | ret = redirect_branch_edge (e, target); |
1439 | if (!ret) | |
1440 | return NULL; | |
5f0d2358 | 1441 | |
6fb5fa3c | 1442 | df_set_bb_dirty (src); |
3371a64f | 1443 | fixup_partition_crossing (ret); |
6de9cd9a | 1444 | return ret; |
ca6c03ca JH |
1445 | } |
1446 | ||
3371a64f TJ |
1447 | /* Emit a barrier after BB, into the footer if we are in CFGLAYOUT mode. */ |
1448 | ||
1449 | void | |
1450 | emit_barrier_after_bb (basic_block bb) | |
1451 | { | |
1452 | rtx barrier = emit_barrier_after (BB_END (bb)); | |
c3284718 | 1453 | gcc_assert (current_ir_type () == IR_RTL_CFGRTL |
3371a64f TJ |
1454 | || current_ir_type () == IR_RTL_CFGLAYOUT); |
1455 | if (current_ir_type () == IR_RTL_CFGLAYOUT) | |
1456 | BB_FOOTER (bb) = unlink_insn_chain (barrier, barrier); | |
1457 | } | |
1458 | ||
4fe9b91c | 1459 | /* Like force_nonfallthru below, but additionally performs redirection |
26898771 BS |
1460 | Used by redirect_edge_and_branch_force. JUMP_LABEL is used only |
1461 | when redirecting to the EXIT_BLOCK, it is either ret_rtx or | |
1462 | simple_return_rtx, indicating which kind of returnjump to create. | |
1463 | It should be NULL otherwise. */ | |
ca6c03ca | 1464 | |
dc0ff1c8 | 1465 | basic_block |
26898771 | 1466 | force_nonfallthru_and_redirect (edge e, basic_block target, rtx jump_label) |
ca6c03ca | 1467 | { |
a3716585 | 1468 | basic_block jump_block, new_bb = NULL, src = e->src; |
ca6c03ca JH |
1469 | rtx note; |
1470 | edge new_edge; | |
a3716585 | 1471 | int abnormal_edge_flags = 0; |
a3e6a37b | 1472 | bool asm_goto_edge = false; |
7241571e | 1473 | int loc; |
ca6c03ca | 1474 | |
cb9a1d9b JH |
1475 | /* In the case the last instruction is conditional jump to the next |
1476 | instruction, first redirect the jump itself and then continue | |
b20b352b | 1477 | by creating a basic block afterwards to redirect fallthru edge. */ |
fefa31b5 DM |
1478 | if (e->src != ENTRY_BLOCK_PTR_FOR_FN (cfun) |
1479 | && e->dest != EXIT_BLOCK_PTR_FOR_FN (cfun) | |
a813c111 | 1480 | && any_condjump_p (BB_END (e->src)) |
a813c111 | 1481 | && JUMP_LABEL (BB_END (e->src)) == BB_HEAD (e->dest)) |
cb9a1d9b JH |
1482 | { |
1483 | rtx note; | |
58e6ae30 | 1484 | edge b = unchecked_make_edge (e->src, target, 0); |
341c100f | 1485 | bool redirected; |
cb9a1d9b | 1486 | |
341c100f NS |
1487 | redirected = redirect_jump (BB_END (e->src), block_label (target), 0); |
1488 | gcc_assert (redirected); | |
c22cacf3 | 1489 | |
a813c111 | 1490 | note = find_reg_note (BB_END (e->src), REG_BR_PROB, NULL_RTX); |
cb9a1d9b JH |
1491 | if (note) |
1492 | { | |
e5af9ddd | 1493 | int prob = XINT (note, 0); |
cb9a1d9b JH |
1494 | |
1495 | b->probability = prob; | |
8ddb5a29 | 1496 | /* Update this to use GCOV_COMPUTE_SCALE. */ |
cb9a1d9b JH |
1497 | b->count = e->count * prob / REG_BR_PROB_BASE; |
1498 | e->probability -= e->probability; | |
1499 | e->count -= b->count; | |
1500 | if (e->probability < 0) | |
1501 | e->probability = 0; | |
1502 | if (e->count < 0) | |
1503 | e->count = 0; | |
1504 | } | |
1505 | } | |
1506 | ||
ca6c03ca | 1507 | if (e->flags & EDGE_ABNORMAL) |
a3716585 JH |
1508 | { |
1509 | /* Irritating special case - fallthru edge to the same block as abnormal | |
1510 | edge. | |
1511 | We can't redirect abnormal edge, but we still can split the fallthru | |
d329e058 | 1512 | one and create separate abnormal edge to original destination. |
a3716585 | 1513 | This allows bb-reorder to make such edge non-fallthru. */ |
341c100f | 1514 | gcc_assert (e->dest == target); |
ee44c28d SB |
1515 | abnormal_edge_flags = e->flags & ~EDGE_FALLTHRU; |
1516 | e->flags &= EDGE_FALLTHRU; | |
a3716585 | 1517 | } |
341c100f | 1518 | else |
24c545ff | 1519 | { |
341c100f | 1520 | gcc_assert (e->flags & EDGE_FALLTHRU); |
fefa31b5 | 1521 | if (e->src == ENTRY_BLOCK_PTR_FOR_FN (cfun)) |
341c100f NS |
1522 | { |
1523 | /* We can't redirect the entry block. Create an empty block | |
628f6a4e BE |
1524 | at the start of the function which we use to add the new |
1525 | jump. */ | |
1526 | edge tmp; | |
1527 | edge_iterator ei; | |
1528 | bool found = false; | |
c22cacf3 | 1529 | |
fefa31b5 DM |
1530 | basic_block bb = create_basic_block (BB_HEAD (e->dest), NULL, |
1531 | ENTRY_BLOCK_PTR_FOR_FN (cfun)); | |
c22cacf3 | 1532 | |
341c100f NS |
1533 | /* Change the existing edge's source to be the new block, and add |
1534 | a new edge from the entry block to the new block. */ | |
1535 | e->src = bb; | |
fefa31b5 DM |
1536 | for (ei = ei_start (ENTRY_BLOCK_PTR_FOR_FN (cfun)->succs); |
1537 | (tmp = ei_safe_edge (ei)); ) | |
628f6a4e BE |
1538 | { |
1539 | if (tmp == e) | |
1540 | { | |
fefa31b5 | 1541 | ENTRY_BLOCK_PTR_FOR_FN (cfun)->succs->unordered_remove (ei.index); |
628f6a4e BE |
1542 | found = true; |
1543 | break; | |
1544 | } | |
1545 | else | |
1546 | ei_next (&ei); | |
1547 | } | |
c22cacf3 | 1548 | |
628f6a4e | 1549 | gcc_assert (found); |
c22cacf3 | 1550 | |
9771b263 | 1551 | vec_safe_push (bb->succs, e); |
fefa31b5 DM |
1552 | make_single_succ_edge (ENTRY_BLOCK_PTR_FOR_FN (cfun), bb, |
1553 | EDGE_FALLTHRU); | |
341c100f | 1554 | } |
24c545ff BS |
1555 | } |
1556 | ||
a3e6a37b | 1557 | /* If e->src ends with asm goto, see if any of the ASM_OPERANDS_LABELs |
891ca07d | 1558 | don't point to the target or fallthru label. */ |
a3e6a37b | 1559 | if (JUMP_P (BB_END (e->src)) |
fefa31b5 | 1560 | && target != EXIT_BLOCK_PTR_FOR_FN (cfun) |
a3e6a37b JJ |
1561 | && (e->flags & EDGE_FALLTHRU) |
1562 | && (note = extract_asm_operands (PATTERN (BB_END (e->src))))) | |
ca6c03ca | 1563 | { |
a3e6a37b | 1564 | int i, n = ASM_OPERANDS_LABEL_LENGTH (note); |
5d68b7e6 | 1565 | bool adjust_jump_target = false; |
a3e6a37b JJ |
1566 | |
1567 | for (i = 0; i < n; ++i) | |
891ca07d JJ |
1568 | { |
1569 | if (XEXP (ASM_OPERANDS_LABEL (note, i), 0) == BB_HEAD (e->dest)) | |
5d68b7e6 JJ |
1570 | { |
1571 | LABEL_NUSES (XEXP (ASM_OPERANDS_LABEL (note, i), 0))--; | |
1572 | XEXP (ASM_OPERANDS_LABEL (note, i), 0) = block_label (target); | |
1573 | LABEL_NUSES (XEXP (ASM_OPERANDS_LABEL (note, i), 0))++; | |
1574 | adjust_jump_target = true; | |
1575 | } | |
891ca07d | 1576 | if (XEXP (ASM_OPERANDS_LABEL (note, i), 0) == BB_HEAD (target)) |
a3e6a37b | 1577 | asm_goto_edge = true; |
891ca07d | 1578 | } |
5d68b7e6 JJ |
1579 | if (adjust_jump_target) |
1580 | { | |
1581 | rtx insn = BB_END (e->src), note; | |
1582 | rtx old_label = BB_HEAD (e->dest); | |
1583 | rtx new_label = BB_HEAD (target); | |
1584 | ||
1585 | if (JUMP_LABEL (insn) == old_label) | |
1586 | { | |
1587 | JUMP_LABEL (insn) = new_label; | |
1588 | note = find_reg_note (insn, REG_LABEL_TARGET, new_label); | |
1589 | if (note) | |
1590 | remove_note (insn, note); | |
1591 | } | |
1592 | else | |
1593 | { | |
1594 | note = find_reg_note (insn, REG_LABEL_TARGET, old_label); | |
1595 | if (note) | |
1596 | remove_note (insn, note); | |
1597 | if (JUMP_LABEL (insn) != new_label | |
1598 | && !find_reg_note (insn, REG_LABEL_TARGET, new_label)) | |
1599 | add_reg_note (insn, REG_LABEL_TARGET, new_label); | |
1600 | } | |
1601 | while ((note = find_reg_note (insn, REG_LABEL_OPERAND, old_label)) | |
1602 | != NULL_RTX) | |
1603 | XEXP (note, 0) = new_label; | |
1604 | } | |
a3e6a37b JJ |
1605 | } |
1606 | ||
1607 | if (EDGE_COUNT (e->src->succs) >= 2 || abnormal_edge_flags || asm_goto_edge) | |
1608 | { | |
1609 | gcov_type count = e->count; | |
1610 | int probability = e->probability; | |
ca6c03ca | 1611 | /* Create the new structures. */ |
31a78298 | 1612 | |
79019985 RH |
1613 | /* If the old block ended with a tablejump, skip its table |
1614 | by searching forward from there. Otherwise start searching | |
1615 | forward from the last instruction of the old block. */ | |
a813c111 SB |
1616 | if (!tablejump_p (BB_END (e->src), NULL, ¬e)) |
1617 | note = BB_END (e->src); | |
31a78298 RH |
1618 | note = NEXT_INSN (note); |
1619 | ||
31a78298 | 1620 | jump_block = create_basic_block (note, NULL, e->src); |
a3e6a37b | 1621 | jump_block->count = count; |
ca6c03ca | 1622 | jump_block->frequency = EDGE_FREQUENCY (e); |
ca6c03ca | 1623 | |
750054a2 CT |
1624 | /* Make sure new block ends up in correct hot/cold section. */ |
1625 | ||
076c7ab8 | 1626 | BB_COPY_PARTITION (jump_block, e->src); |
c22cacf3 | 1627 | |
ca6c03ca JH |
1628 | /* Wire edge in. */ |
1629 | new_edge = make_edge (e->src, jump_block, EDGE_FALLTHRU); | |
a3e6a37b JJ |
1630 | new_edge->probability = probability; |
1631 | new_edge->count = count; | |
ca6c03ca JH |
1632 | |
1633 | /* Redirect old edge. */ | |
1634 | redirect_edge_pred (e, jump_block); | |
1635 | e->probability = REG_BR_PROB_BASE; | |
1636 | ||
3371a64f TJ |
1637 | /* If e->src was previously region crossing, it no longer is |
1638 | and the reg crossing note should be removed. */ | |
1639 | fixup_partition_crossing (new_edge); | |
1640 | ||
a3e6a37b JJ |
1641 | /* If asm goto has any label refs to target's label, |
1642 | add also edge from asm goto bb to target. */ | |
1643 | if (asm_goto_edge) | |
1644 | { | |
1645 | new_edge->probability /= 2; | |
1646 | new_edge->count /= 2; | |
1647 | jump_block->count /= 2; | |
1648 | jump_block->frequency /= 2; | |
1649 | new_edge = make_edge (new_edge->src, target, | |
1650 | e->flags & ~EDGE_FALLTHRU); | |
1651 | new_edge->probability = probability - probability / 2; | |
1652 | new_edge->count = count - count / 2; | |
1653 | } | |
1654 | ||
ca6c03ca JH |
1655 | new_bb = jump_block; |
1656 | } | |
1657 | else | |
1658 | jump_block = e->src; | |
5f0d2358 | 1659 | |
2f13f2de | 1660 | loc = e->goto_locus; |
ca6c03ca | 1661 | e->flags &= ~EDGE_FALLTHRU; |
fefa31b5 | 1662 | if (target == EXIT_BLOCK_PTR_FOR_FN (cfun)) |
ca6c03ca | 1663 | { |
26898771 BS |
1664 | if (jump_label == ret_rtx) |
1665 | { | |
cf22ce3c | 1666 | #ifdef HAVE_return |
26898771 | 1667 | emit_jump_insn_after_setloc (gen_return (), BB_END (jump_block), loc); |
cf22ce3c | 1668 | #else |
26898771 | 1669 | gcc_unreachable (); |
cf22ce3c | 1670 | #endif |
26898771 BS |
1671 | } |
1672 | else | |
1673 | { | |
1674 | gcc_assert (jump_label == simple_return_rtx); | |
1675 | #ifdef HAVE_simple_return | |
1676 | emit_jump_insn_after_setloc (gen_simple_return (), | |
1677 | BB_END (jump_block), loc); | |
1678 | #else | |
1679 | gcc_unreachable (); | |
1680 | #endif | |
1681 | } | |
387748de | 1682 | set_return_jump_label (BB_END (jump_block)); |
ca6c03ca JH |
1683 | } |
1684 | else | |
1685 | { | |
1686 | rtx label = block_label (target); | |
7241571e | 1687 | emit_jump_insn_after_setloc (gen_jump (label), BB_END (jump_block), loc); |
a813c111 | 1688 | JUMP_LABEL (BB_END (jump_block)) = label; |
ca6c03ca JH |
1689 | LABEL_NUSES (label)++; |
1690 | } | |
5f0d2358 | 1691 | |
3371a64f TJ |
1692 | /* We might be in cfg layout mode, and if so, the following routine will |
1693 | insert the barrier correctly. */ | |
1694 | emit_barrier_after_bb (jump_block); | |
ca6c03ca JH |
1695 | redirect_edge_succ_nodup (e, target); |
1696 | ||
a3716585 JH |
1697 | if (abnormal_edge_flags) |
1698 | make_edge (src, target, abnormal_edge_flags); | |
1699 | ||
b8698a0f | 1700 | df_mark_solutions_dirty (); |
3371a64f | 1701 | fixup_partition_crossing (e); |
ca6c03ca JH |
1702 | return new_bb; |
1703 | } | |
1704 | ||
1705 | /* Edge E is assumed to be fallthru edge. Emit needed jump instruction | |
1706 | (and possibly create new basic block) to make edge non-fallthru. | |
1707 | Return newly created BB or NULL if none. */ | |
5f0d2358 | 1708 | |
cf103ca4 EB |
1709 | static basic_block |
1710 | rtl_force_nonfallthru (edge e) | |
ca6c03ca | 1711 | { |
26898771 | 1712 | return force_nonfallthru_and_redirect (e, e->dest, NULL_RTX); |
ca6c03ca JH |
1713 | } |
1714 | ||
1715 | /* Redirect edge even at the expense of creating new jump insn or | |
1716 | basic block. Return new basic block if created, NULL otherwise. | |
41806d92 | 1717 | Conversion must be possible. */ |
ca6c03ca | 1718 | |
9ee634e3 | 1719 | static basic_block |
d329e058 | 1720 | rtl_redirect_edge_and_branch_force (edge e, basic_block target) |
ca6c03ca | 1721 | { |
5f0d2358 RK |
1722 | if (redirect_edge_and_branch (e, target) |
1723 | || e->dest == target) | |
ca6c03ca JH |
1724 | return NULL; |
1725 | ||
1726 | /* In case the edge redirection failed, try to force it to be non-fallthru | |
1727 | and redirect newly created simplejump. */ | |
6fb5fa3c | 1728 | df_set_bb_dirty (e->src); |
26898771 | 1729 | return force_nonfallthru_and_redirect (e, target, NULL_RTX); |
ca6c03ca JH |
1730 | } |
1731 | ||
1732 | /* The given edge should potentially be a fallthru edge. If that is in | |
1733 | fact true, delete the jump and barriers that are in the way. */ | |
1734 | ||
f470c378 ZD |
1735 | static void |
1736 | rtl_tidy_fallthru_edge (edge e) | |
ca6c03ca JH |
1737 | { |
1738 | rtx q; | |
f470c378 ZD |
1739 | basic_block b = e->src, c = b->next_bb; |
1740 | ||
ca6c03ca JH |
1741 | /* ??? In a late-running flow pass, other folks may have deleted basic |
1742 | blocks by nopping out blocks, leaving multiple BARRIERs between here | |
0fa2e4df | 1743 | and the target label. They ought to be chastised and fixed. |
ca6c03ca JH |
1744 | |
1745 | We can also wind up with a sequence of undeletable labels between | |
1746 | one block and the next. | |
1747 | ||
1748 | So search through a sequence of barriers, labels, and notes for | |
1749 | the head of block C and assert that we really do fall through. */ | |
1750 | ||
a813c111 | 1751 | for (q = NEXT_INSN (BB_END (b)); q != BB_HEAD (c); q = NEXT_INSN (q)) |
9c0a0632 RH |
1752 | if (INSN_P (q)) |
1753 | return; | |
ca6c03ca JH |
1754 | |
1755 | /* Remove what will soon cease being the jump insn from the source block. | |
1756 | If block B consisted only of this single jump, turn it into a deleted | |
1757 | note. */ | |
a813c111 | 1758 | q = BB_END (b); |
4b4bf941 | 1759 | if (JUMP_P (q) |
ca6c03ca JH |
1760 | && onlyjump_p (q) |
1761 | && (any_uncondjump_p (q) | |
c5cbcccf | 1762 | || single_succ_p (b))) |
ca6c03ca JH |
1763 | { |
1764 | #ifdef HAVE_cc0 | |
1765 | /* If this was a conditional jump, we need to also delete | |
1766 | the insn that set cc0. */ | |
1767 | if (any_condjump_p (q) && only_sets_cc0_p (PREV_INSN (q))) | |
1768 | q = PREV_INSN (q); | |
1769 | #endif | |
1770 | ||
1771 | q = PREV_INSN (q); | |
ca6c03ca JH |
1772 | } |
1773 | ||
1774 | /* Selectively unlink the sequence. */ | |
a813c111 | 1775 | if (q != PREV_INSN (BB_HEAD (c))) |
a7b87f73 | 1776 | delete_insn_chain (NEXT_INSN (q), PREV_INSN (BB_HEAD (c)), false); |
ca6c03ca JH |
1777 | |
1778 | e->flags |= EDGE_FALLTHRU; | |
1779 | } | |
ca6c03ca | 1780 | \f |
f470c378 ZD |
1781 | /* Should move basic block BB after basic block AFTER. NIY. */ |
1782 | ||
1783 | static bool | |
1784 | rtl_move_block_after (basic_block bb ATTRIBUTE_UNUSED, | |
1785 | basic_block after ATTRIBUTE_UNUSED) | |
1786 | { | |
1787 | return false; | |
1788 | } | |
1789 | ||
3371a64f TJ |
1790 | /* Locate the last bb in the same partition as START_BB. */ |
1791 | ||
1792 | static basic_block | |
1793 | last_bb_in_partition (basic_block start_bb) | |
1794 | { | |
1795 | basic_block bb; | |
fefa31b5 | 1796 | FOR_BB_BETWEEN (bb, start_bb, EXIT_BLOCK_PTR_FOR_FN (cfun), next_bb) |
3371a64f TJ |
1797 | { |
1798 | if (BB_PARTITION (start_bb) != BB_PARTITION (bb->next_bb)) | |
1799 | return bb; | |
1800 | } | |
6626665f | 1801 | /* Return bb before the exit block. */ |
3371a64f TJ |
1802 | return bb->prev_bb; |
1803 | } | |
1804 | ||
ca6c03ca | 1805 | /* Split a (typically critical) edge. Return the new block. |
41806d92 | 1806 | The edge must not be abnormal. |
ca6c03ca JH |
1807 | |
1808 | ??? The code generally expects to be called on critical edges. | |
1809 | The case of a block ending in an unconditional jump to a | |
1810 | block with multiple predecessors is not handled optimally. */ | |
1811 | ||
8ce33230 | 1812 | static basic_block |
d329e058 | 1813 | rtl_split_edge (edge edge_in) |
ca6c03ca | 1814 | { |
3371a64f | 1815 | basic_block bb, new_bb; |
ca6c03ca JH |
1816 | rtx before; |
1817 | ||
1818 | /* Abnormal edges cannot be split. */ | |
341c100f | 1819 | gcc_assert (!(edge_in->flags & EDGE_ABNORMAL)); |
ca6c03ca JH |
1820 | |
1821 | /* We are going to place the new block in front of edge destination. | |
eaec9b3d | 1822 | Avoid existence of fallthru predecessors. */ |
ca6c03ca JH |
1823 | if ((edge_in->flags & EDGE_FALLTHRU) == 0) |
1824 | { | |
0fd4b31d | 1825 | edge e = find_fallthru_edge (edge_in->dest->preds); |
ca6c03ca JH |
1826 | |
1827 | if (e) | |
1828 | force_nonfallthru (e); | |
1829 | } | |
1830 | ||
96e82e0a | 1831 | /* Create the basic block note. */ |
fefa31b5 | 1832 | if (edge_in->dest != EXIT_BLOCK_PTR_FOR_FN (cfun)) |
a813c111 | 1833 | before = BB_HEAD (edge_in->dest); |
ca6c03ca JH |
1834 | else |
1835 | before = NULL_RTX; | |
1836 | ||
623a66fa | 1837 | /* If this is a fall through edge to the exit block, the blocks might be |
ffe14686 | 1838 | not adjacent, and the right place is after the source. */ |
fefa31b5 DM |
1839 | if ((edge_in->flags & EDGE_FALLTHRU) |
1840 | && edge_in->dest == EXIT_BLOCK_PTR_FOR_FN (cfun)) | |
623a66fa R |
1841 | { |
1842 | before = NEXT_INSN (BB_END (edge_in->src)); | |
623a66fa | 1843 | bb = create_basic_block (before, NULL, edge_in->src); |
076c7ab8 | 1844 | BB_COPY_PARTITION (bb, edge_in->src); |
623a66fa R |
1845 | } |
1846 | else | |
9fb32434 | 1847 | { |
fefa31b5 | 1848 | if (edge_in->src == ENTRY_BLOCK_PTR_FOR_FN (cfun)) |
3371a64f TJ |
1849 | { |
1850 | bb = create_basic_block (before, NULL, edge_in->dest->prev_bb); | |
1851 | BB_COPY_PARTITION (bb, edge_in->dest); | |
1852 | } | |
1853 | else | |
1854 | { | |
1855 | basic_block after = edge_in->dest->prev_bb; | |
1856 | /* If this is post-bb reordering, and the edge crosses a partition | |
1857 | boundary, the new block needs to be inserted in the bb chain | |
1858 | at the end of the src partition (since we put the new bb into | |
1859 | that partition, see below). Otherwise we may end up creating | |
1860 | an extra partition crossing in the chain, which is illegal. | |
1861 | It can't go after the src, because src may have a fall-through | |
1862 | to a different block. */ | |
1863 | if (crtl->bb_reorder_complete | |
1864 | && (edge_in->flags & EDGE_CROSSING)) | |
1865 | { | |
1866 | after = last_bb_in_partition (edge_in->src); | |
1867 | before = NEXT_INSN (BB_END (after)); | |
1868 | /* The instruction following the last bb in partition should | |
1869 | be a barrier, since it cannot end in a fall-through. */ | |
1870 | gcc_checking_assert (BARRIER_P (before)); | |
1871 | before = NEXT_INSN (before); | |
1872 | } | |
1873 | bb = create_basic_block (before, NULL, after); | |
1874 | /* Put the split bb into the src partition, to avoid creating | |
1875 | a situation where a cold bb dominates a hot bb, in the case | |
1876 | where src is cold and dest is hot. The src will dominate | |
1877 | the new bb (whereas it might not have dominated dest). */ | |
1878 | BB_COPY_PARTITION (bb, edge_in->src); | |
1879 | } | |
9fb32434 | 1880 | } |
ca6c03ca | 1881 | |
4977bab6 | 1882 | make_single_succ_edge (bb, edge_in->dest, EDGE_FALLTHRU); |
ca6c03ca | 1883 | |
3371a64f TJ |
1884 | /* Can't allow a region crossing edge to be fallthrough. */ |
1885 | if (BB_PARTITION (bb) != BB_PARTITION (edge_in->dest) | |
fefa31b5 | 1886 | && edge_in->dest != EXIT_BLOCK_PTR_FOR_FN (cfun)) |
3371a64f TJ |
1887 | { |
1888 | new_bb = force_nonfallthru (single_succ_edge (bb)); | |
1889 | gcc_assert (!new_bb); | |
1890 | } | |
1891 | ||
4d6922ee | 1892 | /* For non-fallthru edges, we must adjust the predecessor's |
ca6c03ca JH |
1893 | jump instruction to target our new block. */ |
1894 | if ((edge_in->flags & EDGE_FALLTHRU) == 0) | |
1895 | { | |
341c100f NS |
1896 | edge redirected = redirect_edge_and_branch (edge_in, bb); |
1897 | gcc_assert (redirected); | |
ca6c03ca JH |
1898 | } |
1899 | else | |
3b5fda81 | 1900 | { |
fefa31b5 | 1901 | if (edge_in->src != ENTRY_BLOCK_PTR_FOR_FN (cfun)) |
3b5fda81 JJ |
1902 | { |
1903 | /* For asm goto even splitting of fallthru edge might | |
1904 | need insn patching, as other labels might point to the | |
1905 | old label. */ | |
1906 | rtx last = BB_END (edge_in->src); | |
1907 | if (last | |
1908 | && JUMP_P (last) | |
fefa31b5 | 1909 | && edge_in->dest != EXIT_BLOCK_PTR_FOR_FN (cfun) |
3b5fda81 JJ |
1910 | && extract_asm_operands (PATTERN (last)) != NULL_RTX |
1911 | && patch_jump_insn (last, before, bb)) | |
1912 | df_set_bb_dirty (edge_in->src); | |
1913 | } | |
1914 | redirect_edge_succ (edge_in, bb); | |
1915 | } | |
ca6c03ca JH |
1916 | |
1917 | return bb; | |
1918 | } | |
1919 | ||
1920 | /* Queue instructions for insertion on an edge between two basic blocks. | |
1921 | The new instructions and basic blocks (if any) will not appear in the | |
1922 | CFG until commit_edge_insertions is called. */ | |
1923 | ||
1924 | void | |
d329e058 | 1925 | insert_insn_on_edge (rtx pattern, edge e) |
ca6c03ca JH |
1926 | { |
1927 | /* We cannot insert instructions on an abnormal critical edge. | |
1928 | It will be easier to find the culprit if we die now. */ | |
341c100f | 1929 | gcc_assert (!((e->flags & EDGE_ABNORMAL) && EDGE_CRITICAL_P (e))); |
ca6c03ca | 1930 | |
6de9cd9a | 1931 | if (e->insns.r == NULL_RTX) |
ca6c03ca JH |
1932 | start_sequence (); |
1933 | else | |
6de9cd9a | 1934 | push_to_sequence (e->insns.r); |
ca6c03ca JH |
1935 | |
1936 | emit_insn (pattern); | |
1937 | ||
6de9cd9a | 1938 | e->insns.r = get_insns (); |
ca6c03ca JH |
1939 | end_sequence (); |
1940 | } | |
1941 | ||
1942 | /* Update the CFG for the instructions queued on edge E. */ | |
1943 | ||
4e3825db | 1944 | void |
2ac66157 | 1945 | commit_one_edge_insertion (edge e) |
ca6c03ca JH |
1946 | { |
1947 | rtx before = NULL_RTX, after = NULL_RTX, insns, tmp, last; | |
898c90c0 | 1948 | basic_block bb; |
ca6c03ca JH |
1949 | |
1950 | /* Pull the insns off the edge now since the edge might go away. */ | |
6de9cd9a DN |
1951 | insns = e->insns.r; |
1952 | e->insns.r = NULL_RTX; | |
ca6c03ca | 1953 | |
898c90c0 EB |
1954 | /* Figure out where to put these insns. If the destination has |
1955 | one predecessor, insert there. Except for the exit block. */ | |
fefa31b5 | 1956 | if (single_pred_p (e->dest) && e->dest != EXIT_BLOCK_PTR_FOR_FN (cfun)) |
ca6c03ca | 1957 | { |
898c90c0 EB |
1958 | bb = e->dest; |
1959 | ||
1960 | /* Get the location correct wrt a code label, and "nice" wrt | |
1961 | a basic block note, and before everything else. */ | |
1962 | tmp = BB_HEAD (bb); | |
1963 | if (LABEL_P (tmp)) | |
1964 | tmp = NEXT_INSN (tmp); | |
1965 | if (NOTE_INSN_BASIC_BLOCK_P (tmp)) | |
1966 | tmp = NEXT_INSN (tmp); | |
1967 | if (tmp == BB_HEAD (bb)) | |
1968 | before = tmp; | |
1969 | else if (tmp) | |
1970 | after = PREV_INSN (tmp); | |
1971 | else | |
1972 | after = get_last_insn (); | |
1973 | } | |
3dec4024 | 1974 | |
898c90c0 | 1975 | /* If the source has one successor and the edge is not abnormal, |
a1d50386 JJ |
1976 | insert there. Except for the entry block. |
1977 | Don't do this if the predecessor ends in a jump other than | |
1978 | unconditional simple jump. E.g. for asm goto that points all | |
1979 | its labels at the fallthru basic block, we can't insert instructions | |
1980 | before the asm goto, as the asm goto can have various of side effects, | |
1981 | and can't emit instructions after the asm goto, as it must end | |
1982 | the basic block. */ | |
898c90c0 EB |
1983 | else if ((e->flags & EDGE_ABNORMAL) == 0 |
1984 | && single_succ_p (e->src) | |
fefa31b5 | 1985 | && e->src != ENTRY_BLOCK_PTR_FOR_FN (cfun) |
a1d50386 JJ |
1986 | && (!JUMP_P (BB_END (e->src)) |
1987 | || simplejump_p (BB_END (e->src)))) | |
898c90c0 EB |
1988 | { |
1989 | bb = e->src; | |
3dec4024 | 1990 | |
898c90c0 EB |
1991 | /* It is possible to have a non-simple jump here. Consider a target |
1992 | where some forms of unconditional jumps clobber a register. This | |
1993 | happens on the fr30 for example. | |
ca6c03ca | 1994 | |
898c90c0 EB |
1995 | We know this block has a single successor, so we can just emit |
1996 | the queued insns before the jump. */ | |
1997 | if (JUMP_P (BB_END (bb))) | |
1998 | before = BB_END (bb); | |
3dec4024 JH |
1999 | else |
2000 | { | |
898c90c0 EB |
2001 | /* We'd better be fallthru, or we've lost track of what's what. */ |
2002 | gcc_assert (e->flags & EDGE_FALLTHRU); | |
750054a2 | 2003 | |
898c90c0 | 2004 | after = BB_END (bb); |
ca6c03ca JH |
2005 | } |
2006 | } | |
2007 | ||
898c90c0 EB |
2008 | /* Otherwise we must split the edge. */ |
2009 | else | |
2010 | { | |
2011 | bb = split_edge (e); | |
3371a64f TJ |
2012 | |
2013 | /* If E crossed a partition boundary, we needed to make bb end in | |
2014 | a region-crossing jump, even though it was originally fallthru. */ | |
2015 | if (JUMP_P (BB_END (bb))) | |
2016 | before = BB_END (bb); | |
2017 | else | |
2018 | after = BB_END (bb); | |
898c90c0 EB |
2019 | } |
2020 | ||
2021 | /* Now that we've found the spot, do the insertion. */ | |
ca6c03ca JH |
2022 | if (before) |
2023 | { | |
6fb5fa3c | 2024 | emit_insn_before_noloc (insns, before, bb); |
ca6c03ca JH |
2025 | last = prev_nonnote_insn (before); |
2026 | } | |
2027 | else | |
6fb5fa3c | 2028 | last = emit_insn_after_noloc (insns, after, bb); |
ca6c03ca JH |
2029 | |
2030 | if (returnjump_p (last)) | |
2031 | { | |
2032 | /* ??? Remove all outgoing edges from BB and add one for EXIT. | |
c22cacf3 MS |
2033 | This is not currently a problem because this only happens |
2034 | for the (single) epilogue, which already has a fallthru edge | |
2035 | to EXIT. */ | |
ca6c03ca | 2036 | |
c5cbcccf | 2037 | e = single_succ_edge (bb); |
fefa31b5 | 2038 | gcc_assert (e->dest == EXIT_BLOCK_PTR_FOR_FN (cfun) |
c5cbcccf | 2039 | && single_succ_p (bb) && (e->flags & EDGE_FALLTHRU)); |
ca6c03ca | 2040 | |
5f0d2358 | 2041 | e->flags &= ~EDGE_FALLTHRU; |
ca6c03ca | 2042 | emit_barrier_after (last); |
0b17ab2f | 2043 | |
ca6c03ca JH |
2044 | if (before) |
2045 | delete_insn (before); | |
2046 | } | |
341c100f NS |
2047 | else |
2048 | gcc_assert (!JUMP_P (last)); | |
ca6c03ca JH |
2049 | } |
2050 | ||
2051 | /* Update the CFG for all queued instructions. */ | |
2052 | ||
2053 | void | |
d329e058 | 2054 | commit_edge_insertions (void) |
ca6c03ca | 2055 | { |
ca6c03ca JH |
2056 | basic_block bb; |
2057 | ||
600b5b1d TJ |
2058 | /* Optimization passes that invoke this routine can cause hot blocks |
2059 | previously reached by both hot and cold blocks to become dominated only | |
2060 | by cold blocks. This will cause the verification below to fail, | |
2061 | and lead to now cold code in the hot section. In some cases this | |
2062 | may only be visible after newly unreachable blocks are deleted, | |
2063 | which will be done by fixup_partitions. */ | |
2064 | fixup_partitions (); | |
2065 | ||
ca6c03ca JH |
2066 | #ifdef ENABLE_CHECKING |
2067 | verify_flow_info (); | |
2068 | #endif | |
2069 | ||
fefa31b5 DM |
2070 | FOR_BB_BETWEEN (bb, ENTRY_BLOCK_PTR_FOR_FN (cfun), |
2071 | EXIT_BLOCK_PTR_FOR_FN (cfun), next_bb) | |
ca6c03ca | 2072 | { |
628f6a4e BE |
2073 | edge e; |
2074 | edge_iterator ei; | |
ca6c03ca | 2075 | |
628f6a4e BE |
2076 | FOR_EACH_EDGE (e, ei, bb->succs) |
2077 | if (e->insns.r) | |
cf103ca4 | 2078 | commit_one_edge_insertion (e); |
3dec4024 | 2079 | } |
ca6c03ca JH |
2080 | } |
2081 | \f | |
6fb5fa3c | 2082 | |
f470c378 | 2083 | /* Print out RTL-specific basic block information (live information |
a315c44c SB |
2084 | at start and end with TDF_DETAILS). FLAGS are the TDF_* masks |
2085 | documented in dumpfile.h. */ | |
ca6c03ca | 2086 | |
10e9fecc | 2087 | static void |
a315c44c | 2088 | rtl_dump_bb (FILE *outf, basic_block bb, int indent, int flags) |
ca6c03ca JH |
2089 | { |
2090 | rtx insn; | |
2091 | rtx last; | |
f470c378 | 2092 | char *s_indent; |
ca6c03ca | 2093 | |
ae50c0cb | 2094 | s_indent = (char *) alloca ((size_t) indent + 1); |
400e39e3 | 2095 | memset (s_indent, ' ', (size_t) indent); |
f470c378 | 2096 | s_indent[indent] = '\0'; |
b8698a0f | 2097 | |
a315c44c | 2098 | if (df && (flags & TDF_DETAILS)) |
6fb5fa3c DB |
2099 | { |
2100 | df_dump_top (bb, outf); | |
2101 | putc ('\n', outf); | |
2102 | } | |
ca6c03ca | 2103 | |
68cc3174 EB |
2104 | if (bb->index != ENTRY_BLOCK && bb->index != EXIT_BLOCK) |
2105 | for (insn = BB_HEAD (bb), last = NEXT_INSN (BB_END (bb)); insn != last; | |
2106 | insn = NEXT_INSN (insn)) | |
a315c44c | 2107 | { |
7b19209f SB |
2108 | if (flags & TDF_DETAILS) |
2109 | df_dump_insn_top (insn, outf); | |
a315c44c SB |
2110 | if (! (flags & TDF_SLIM)) |
2111 | print_rtl_single (outf, insn); | |
2112 | else | |
2113 | dump_insn_slim (outf, insn); | |
7b19209f SB |
2114 | if (flags & TDF_DETAILS) |
2115 | df_dump_insn_bottom (insn, outf); | |
a315c44c SB |
2116 | } |
2117 | ||
2118 | if (df && (flags & TDF_DETAILS)) | |
6fb5fa3c DB |
2119 | { |
2120 | df_dump_bottom (bb, outf); | |
2121 | putc ('\n', outf); | |
2122 | } | |
2123 | ||
ca6c03ca JH |
2124 | } |
2125 | \f | |
c4669594 SB |
2126 | /* Like dump_function_to_file, but for RTL. Print out dataflow information |
2127 | for the start of each basic block. FLAGS are the TDF_* masks documented | |
2128 | in dumpfile.h. */ | |
ca6c03ca JH |
2129 | |
2130 | void | |
a315c44c | 2131 | print_rtl_with_bb (FILE *outf, const_rtx rtx_first, int flags) |
ca6c03ca | 2132 | { |
22ea9ec0 | 2133 | const_rtx tmp_rtx; |
ca6c03ca JH |
2134 | if (rtx_first == 0) |
2135 | fprintf (outf, "(nil)\n"); | |
2136 | else | |
2137 | { | |
ca6c03ca JH |
2138 | enum bb_state { NOT_IN_BB, IN_ONE_BB, IN_MULTIPLE_BB }; |
2139 | int max_uid = get_max_uid (); | |
5ed6ace5 MD |
2140 | basic_block *start = XCNEWVEC (basic_block, max_uid); |
2141 | basic_block *end = XCNEWVEC (basic_block, max_uid); | |
2142 | enum bb_state *in_bb_p = XCNEWVEC (enum bb_state, max_uid); | |
e0082a72 ZD |
2143 | basic_block bb; |
2144 | ||
c4669594 SB |
2145 | /* After freeing the CFG, we still have BLOCK_FOR_INSN set on most |
2146 | insns, but the CFG is not maintained so the basic block info | |
2147 | is not reliable. Therefore it's omitted from the dumps. */ | |
2148 | if (! (cfun->curr_properties & PROP_cfg)) | |
2149 | flags &= ~TDF_BLOCKS; | |
2150 | ||
6fb5fa3c DB |
2151 | if (df) |
2152 | df_dump_start (outf); | |
2153 | ||
c4669594 | 2154 | if (flags & TDF_BLOCKS) |
ca6c03ca | 2155 | { |
4f42035e | 2156 | FOR_EACH_BB_REVERSE_FN (bb, cfun) |
ca6c03ca | 2157 | { |
c4669594 SB |
2158 | rtx x; |
2159 | ||
2160 | start[INSN_UID (BB_HEAD (bb))] = bb; | |
2161 | end[INSN_UID (BB_END (bb))] = bb; | |
2162 | for (x = BB_HEAD (bb); x != NULL_RTX; x = NEXT_INSN (x)) | |
2163 | { | |
2164 | enum bb_state state = IN_MULTIPLE_BB; | |
5f0d2358 | 2165 | |
c4669594 SB |
2166 | if (in_bb_p[INSN_UID (x)] == NOT_IN_BB) |
2167 | state = IN_ONE_BB; | |
2168 | in_bb_p[INSN_UID (x)] = state; | |
ca6c03ca | 2169 | |
c4669594 SB |
2170 | if (x == BB_END (bb)) |
2171 | break; | |
2172 | } | |
ca6c03ca JH |
2173 | } |
2174 | } | |
2175 | ||
2176 | for (tmp_rtx = rtx_first; NULL != tmp_rtx; tmp_rtx = NEXT_INSN (tmp_rtx)) | |
2177 | { | |
c4669594 SB |
2178 | if (flags & TDF_BLOCKS) |
2179 | { | |
2180 | bb = start[INSN_UID (tmp_rtx)]; | |
2181 | if (bb != NULL) | |
2182 | { | |
2183 | dump_bb_info (outf, bb, 0, dump_flags | TDF_COMMENT, true, false); | |
2184 | if (df && (flags & TDF_DETAILS)) | |
2185 | df_dump_top (bb, outf); | |
2186 | } | |
ca6c03ca | 2187 | |
c4669594 SB |
2188 | if (in_bb_p[INSN_UID (tmp_rtx)] == NOT_IN_BB |
2189 | && !NOTE_P (tmp_rtx) | |
2190 | && !BARRIER_P (tmp_rtx)) | |
2191 | fprintf (outf, ";; Insn is not within a basic block\n"); | |
2192 | else if (in_bb_p[INSN_UID (tmp_rtx)] == IN_MULTIPLE_BB) | |
2193 | fprintf (outf, ";; Insn is in multiple basic blocks\n"); | |
2194 | } | |
ca6c03ca | 2195 | |
7b19209f SB |
2196 | if (flags & TDF_DETAILS) |
2197 | df_dump_insn_top (tmp_rtx, outf); | |
a315c44c SB |
2198 | if (! (flags & TDF_SLIM)) |
2199 | print_rtl_single (outf, tmp_rtx); | |
2200 | else | |
2201 | dump_insn_slim (outf, tmp_rtx); | |
7b19209f SB |
2202 | if (flags & TDF_DETAILS) |
2203 | df_dump_insn_bottom (tmp_rtx, outf); | |
ca6c03ca | 2204 | |
c4669594 SB |
2205 | if (flags & TDF_BLOCKS) |
2206 | { | |
2207 | bb = end[INSN_UID (tmp_rtx)]; | |
2208 | if (bb != NULL) | |
2209 | { | |
2210 | dump_bb_info (outf, bb, 0, dump_flags | TDF_COMMENT, false, true); | |
2211 | if (df && (flags & TDF_DETAILS)) | |
2212 | df_dump_bottom (bb, outf); | |
1b03a96d | 2213 | putc ('\n', outf); |
c4669594 SB |
2214 | } |
2215 | } | |
ca6c03ca JH |
2216 | } |
2217 | ||
2218 | free (start); | |
2219 | free (end); | |
2220 | free (in_bb_p); | |
2221 | } | |
ca6c03ca JH |
2222 | } |
2223 | \f | |
532aafad SB |
2224 | /* Update the branch probability of BB if a REG_BR_PROB is present. */ |
2225 | ||
b446e5a2 | 2226 | void |
d329e058 | 2227 | update_br_prob_note (basic_block bb) |
b446e5a2 JH |
2228 | { |
2229 | rtx note; | |
4b4bf941 | 2230 | if (!JUMP_P (BB_END (bb))) |
b446e5a2 | 2231 | return; |
a813c111 | 2232 | note = find_reg_note (BB_END (bb), REG_BR_PROB, NULL_RTX); |
e5af9ddd | 2233 | if (!note || XINT (note, 0) == BRANCH_EDGE (bb)->probability) |
b446e5a2 | 2234 | return; |
e5af9ddd | 2235 | XINT (note, 0) = BRANCH_EDGE (bb)->probability; |
b446e5a2 | 2236 | } |
96370780 MK |
2237 | |
2238 | /* Get the last insn associated with block BB (that includes barriers and | |
2239 | tablejumps after BB). */ | |
2240 | rtx | |
2241 | get_last_bb_insn (basic_block bb) | |
2242 | { | |
2243 | rtx tmp; | |
2244 | rtx end = BB_END (bb); | |
2245 | ||
2246 | /* Include any jump table following the basic block. */ | |
2247 | if (tablejump_p (end, NULL, &tmp)) | |
2248 | end = tmp; | |
2249 | ||
2250 | /* Include any barriers that may follow the basic block. */ | |
1e211590 | 2251 | tmp = next_nonnote_insn_bb (end); |
96370780 MK |
2252 | while (tmp && BARRIER_P (tmp)) |
2253 | { | |
2254 | end = tmp; | |
1e211590 | 2255 | tmp = next_nonnote_insn_bb (end); |
96370780 MK |
2256 | } |
2257 | ||
2258 | return end; | |
2259 | } | |
af205f67 | 2260 | |
600b5b1d TJ |
2261 | /* Sanity check partition hotness to ensure that basic blocks in |
2262 | the cold partition don't dominate basic blocks in the hot partition. | |
2263 | If FLAG_ONLY is true, report violations as errors. Otherwise | |
2264 | re-mark the dominated blocks as cold, since this is run after | |
2265 | cfg optimizations that may make hot blocks previously reached | |
2266 | by both hot and cold blocks now only reachable along cold paths. */ | |
2267 | ||
2268 | static vec<basic_block> | |
2269 | find_partition_fixes (bool flag_only) | |
2270 | { | |
2271 | basic_block bb; | |
2272 | vec<basic_block> bbs_in_cold_partition = vNULL; | |
2273 | vec<basic_block> bbs_to_fix = vNULL; | |
2274 | ||
2275 | /* Callers check this. */ | |
2276 | gcc_checking_assert (crtl->has_bb_partition); | |
2277 | ||
11cd3bed | 2278 | FOR_EACH_BB_FN (bb, cfun) |
600b5b1d TJ |
2279 | if ((BB_PARTITION (bb) == BB_COLD_PARTITION)) |
2280 | bbs_in_cold_partition.safe_push (bb); | |
2281 | ||
2282 | if (bbs_in_cold_partition.is_empty ()) | |
2283 | return vNULL; | |
2284 | ||
2285 | bool dom_calculated_here = !dom_info_available_p (CDI_DOMINATORS); | |
2286 | ||
2287 | if (dom_calculated_here) | |
2288 | calculate_dominance_info (CDI_DOMINATORS); | |
2289 | ||
2290 | while (! bbs_in_cold_partition.is_empty ()) | |
2291 | { | |
2292 | bb = bbs_in_cold_partition.pop (); | |
2293 | /* Any blocks dominated by a block in the cold section | |
2294 | must also be cold. */ | |
2295 | basic_block son; | |
2296 | for (son = first_dom_son (CDI_DOMINATORS, bb); | |
2297 | son; | |
2298 | son = next_dom_son (CDI_DOMINATORS, son)) | |
2299 | { | |
2300 | /* If son is not yet cold, then mark it cold here and | |
2301 | enqueue it for further processing. */ | |
2302 | if ((BB_PARTITION (son) != BB_COLD_PARTITION)) | |
2303 | { | |
2304 | if (flag_only) | |
2305 | error ("non-cold basic block %d dominated " | |
2306 | "by a block in the cold partition (%d)", son->index, bb->index); | |
2307 | else | |
2308 | BB_SET_PARTITION (son, BB_COLD_PARTITION); | |
2309 | bbs_to_fix.safe_push (son); | |
2310 | bbs_in_cold_partition.safe_push (son); | |
2311 | } | |
2312 | } | |
2313 | } | |
2314 | ||
2315 | if (dom_calculated_here) | |
2316 | free_dominance_info (CDI_DOMINATORS); | |
2317 | ||
2318 | return bbs_to_fix; | |
2319 | } | |
2320 | ||
2321 | /* Perform cleanup on the hot/cold bb partitioning after optimization | |
2322 | passes that modify the cfg. */ | |
2323 | ||
2324 | void | |
2325 | fixup_partitions (void) | |
2326 | { | |
2327 | basic_block bb; | |
2328 | ||
2329 | if (!crtl->has_bb_partition) | |
2330 | return; | |
2331 | ||
2332 | /* Delete any blocks that became unreachable and weren't | |
2333 | already cleaned up, for example during edge forwarding | |
2334 | and convert_jumps_to_returns. This will expose more | |
2335 | opportunities for fixing the partition boundaries here. | |
2336 | Also, the calculation of the dominance graph during verification | |
2337 | will assert if there are unreachable nodes. */ | |
2338 | delete_unreachable_blocks (); | |
2339 | ||
2340 | /* If there are partitions, do a sanity check on them: A basic block in | |
2341 | a cold partition cannot dominate a basic block in a hot partition. | |
2342 | Fixup any that now violate this requirement, as a result of edge | |
2343 | forwarding and unreachable block deletion. */ | |
2344 | vec<basic_block> bbs_to_fix = find_partition_fixes (false); | |
2345 | ||
2346 | /* Do the partition fixup after all necessary blocks have been converted to | |
2347 | cold, so that we only update the region crossings the minimum number of | |
2348 | places, which can require forcing edges to be non fallthru. */ | |
2349 | while (! bbs_to_fix.is_empty ()) | |
2350 | { | |
2351 | bb = bbs_to_fix.pop (); | |
2352 | fixup_new_cold_bb (bb); | |
2353 | } | |
2354 | } | |
2355 | ||
af205f67 TJ |
2356 | /* Verify, in the basic block chain, that there is at most one switch |
2357 | between hot/cold partitions. This condition will not be true until | |
2358 | after reorder_basic_blocks is called. */ | |
2359 | ||
251a41b9 | 2360 | static int |
af205f67 TJ |
2361 | verify_hot_cold_block_grouping (void) |
2362 | { | |
2363 | basic_block bb; | |
2364 | int err = 0; | |
2365 | bool switched_sections = false; | |
2366 | int current_partition = BB_UNPARTITIONED; | |
2367 | ||
3371a64f TJ |
2368 | /* Even after bb reordering is complete, we go into cfglayout mode |
2369 | again (in compgoto). Ensure we don't call this before going back | |
2370 | into linearized RTL when any layout fixes would have been committed. */ | |
2371 | if (!crtl->bb_reorder_complete | |
c3284718 | 2372 | || current_ir_type () != IR_RTL_CFGRTL) |
251a41b9 | 2373 | return err; |
af205f67 | 2374 | |
11cd3bed | 2375 | FOR_EACH_BB_FN (bb, cfun) |
af205f67 TJ |
2376 | { |
2377 | if (current_partition != BB_UNPARTITIONED | |
2378 | && BB_PARTITION (bb) != current_partition) | |
2379 | { | |
2380 | if (switched_sections) | |
2381 | { | |
2382 | error ("multiple hot/cold transitions found (bb %i)", | |
2383 | bb->index); | |
2384 | err = 1; | |
2385 | } | |
2386 | else | |
2387 | switched_sections = true; | |
2388 | ||
2389 | if (!crtl->has_bb_partition) | |
2390 | error ("partition found but function partition flag not set"); | |
2391 | } | |
2392 | current_partition = BB_PARTITION (bb); | |
2393 | } | |
2394 | ||
251a41b9 | 2395 | return err; |
af205f67 | 2396 | } |
b446e5a2 | 2397 | \f |
ca6c03ca | 2398 | |
251a41b9 TJ |
2399 | /* Perform several checks on the edges out of each block, such as |
2400 | the consistency of the branch probabilities, the correctness | |
2401 | of hot/cold partition crossing edges, and the number of expected | |
600b5b1d TJ |
2402 | successor edges. Also verify that the dominance relationship |
2403 | between hot/cold blocks is sane. */ | |
f470c378 | 2404 | |
10e9fecc | 2405 | static int |
251a41b9 | 2406 | rtl_verify_edges (void) |
ca6c03ca | 2407 | { |
10e9fecc | 2408 | int err = 0; |
94eb5ddb | 2409 | basic_block bb; |
ca6c03ca | 2410 | |
4f42035e | 2411 | FOR_EACH_BB_REVERSE_FN (bb, cfun) |
ca6c03ca | 2412 | { |
f99ffaa3 EB |
2413 | int n_fallthru = 0, n_branch = 0, n_abnormal_call = 0, n_sibcall = 0; |
2414 | int n_eh = 0, n_abnormal = 0; | |
3cf54412 | 2415 | edge e, fallthru = NULL; |
628f6a4e | 2416 | edge_iterator ei; |
251a41b9 | 2417 | rtx note; |
3371a64f | 2418 | bool has_crossing_edge = false; |
ca6c03ca | 2419 | |
2085a21f | 2420 | if (JUMP_P (BB_END (bb)) |
a813c111 | 2421 | && (note = find_reg_note (BB_END (bb), REG_BR_PROB, NULL_RTX)) |
628f6a4e | 2422 | && EDGE_COUNT (bb->succs) >= 2 |
a813c111 | 2423 | && any_condjump_p (BB_END (bb))) |
5a1a3e5e | 2424 | { |
e5af9ddd | 2425 | if (XINT (note, 0) != BRANCH_EDGE (bb)->probability |
0a6a6ac9 | 2426 | && profile_status_for_fn (cfun) != PROFILE_ABSENT) |
5a1a3e5e | 2427 | { |
e5af9ddd RS |
2428 | error ("verify_flow_info: REG_BR_PROB does not match cfg %i %i", |
2429 | XINT (note, 0), BRANCH_EDGE (bb)->probability); | |
5a1a3e5e JH |
2430 | err = 1; |
2431 | } | |
2432 | } | |
251a41b9 | 2433 | |
628f6a4e | 2434 | FOR_EACH_EDGE (e, ei, bb->succs) |
ca6c03ca | 2435 | { |
0be7e7a6 RH |
2436 | bool is_crossing; |
2437 | ||
ca6c03ca | 2438 | if (e->flags & EDGE_FALLTHRU) |
0be7e7a6 RH |
2439 | n_fallthru++, fallthru = e; |
2440 | ||
2441 | is_crossing = (BB_PARTITION (e->src) != BB_PARTITION (e->dest) | |
fefa31b5 DM |
2442 | && e->src != ENTRY_BLOCK_PTR_FOR_FN (cfun) |
2443 | && e->dest != EXIT_BLOCK_PTR_FOR_FN (cfun)); | |
3371a64f | 2444 | has_crossing_edge |= is_crossing; |
0be7e7a6 | 2445 | if (e->flags & EDGE_CROSSING) |
750054a2 | 2446 | { |
0be7e7a6 RH |
2447 | if (!is_crossing) |
2448 | { | |
2449 | error ("EDGE_CROSSING incorrectly set across same section"); | |
2450 | err = 1; | |
2451 | } | |
2452 | if (e->flags & EDGE_FALLTHRU) | |
2453 | { | |
f99ffaa3 | 2454 | error ("fallthru edge crosses section boundary in bb %i", |
750054a2 CT |
2455 | e->src->index); |
2456 | err = 1; | |
2457 | } | |
0be7e7a6 RH |
2458 | if (e->flags & EDGE_EH) |
2459 | { | |
f99ffaa3 | 2460 | error ("EH edge crosses section boundary in bb %i", |
0be7e7a6 RH |
2461 | e->src->index); |
2462 | err = 1; | |
2463 | } | |
3371a64f TJ |
2464 | if (JUMP_P (BB_END (bb)) |
2465 | && !find_reg_note (BB_END (bb), REG_CROSSING_JUMP, NULL_RTX)) | |
2466 | { | |
2467 | error ("No region crossing jump at section boundary in bb %i", | |
2468 | bb->index); | |
2469 | err = 1; | |
2470 | } | |
0be7e7a6 RH |
2471 | } |
2472 | else if (is_crossing) | |
2473 | { | |
2474 | error ("EDGE_CROSSING missing across section boundary"); | |
2475 | err = 1; | |
750054a2 | 2476 | } |
3dec4024 | 2477 | |
65f43cdf ZD |
2478 | if ((e->flags & ~(EDGE_DFS_BACK |
2479 | | EDGE_CAN_FALLTHRU | |
2480 | | EDGE_IRREDUCIBLE_LOOP | |
9beb1c84 | 2481 | | EDGE_LOOP_EXIT |
7e872b90 JJ |
2482 | | EDGE_CROSSING |
2483 | | EDGE_PRESERVE)) == 0) | |
3dec4024 JH |
2484 | n_branch++; |
2485 | ||
2486 | if (e->flags & EDGE_ABNORMAL_CALL) | |
f99ffaa3 EB |
2487 | n_abnormal_call++; |
2488 | ||
2489 | if (e->flags & EDGE_SIBCALL) | |
2490 | n_sibcall++; | |
3dec4024 JH |
2491 | |
2492 | if (e->flags & EDGE_EH) | |
2493 | n_eh++; | |
f99ffaa3 EB |
2494 | |
2495 | if (e->flags & EDGE_ABNORMAL) | |
3dec4024 | 2496 | n_abnormal++; |
ca6c03ca | 2497 | } |
5f0d2358 | 2498 | |
3371a64f TJ |
2499 | if (!has_crossing_edge |
2500 | && find_reg_note (BB_END (bb), REG_CROSSING_JUMP, NULL_RTX)) | |
2501 | { | |
2502 | print_rtl_with_bb (stderr, get_insns (), TDF_RTL | TDF_BLOCKS | TDF_DETAILS); | |
2503 | error ("Region crossing jump across same section in bb %i", | |
2504 | bb->index); | |
2505 | err = 1; | |
2506 | } | |
2507 | ||
1d65f45c | 2508 | if (n_eh && !find_reg_note (BB_END (bb), REG_EH_REGION, NULL_RTX)) |
3dec4024 | 2509 | { |
f99ffaa3 | 2510 | error ("missing REG_EH_REGION note at the end of bb %i", bb->index); |
3dec4024 JH |
2511 | err = 1; |
2512 | } | |
1d65f45c RH |
2513 | if (n_eh > 1) |
2514 | { | |
f99ffaa3 | 2515 | error ("too many exception handling edges in bb %i", bb->index); |
1d65f45c RH |
2516 | err = 1; |
2517 | } | |
3dec4024 | 2518 | if (n_branch |
4b4bf941 | 2519 | && (!JUMP_P (BB_END (bb)) |
a813c111 SB |
2520 | || (n_branch > 1 && (any_uncondjump_p (BB_END (bb)) |
2521 | || any_condjump_p (BB_END (bb)))))) | |
3dec4024 | 2522 | { |
ab532386 | 2523 | error ("too many outgoing branch edges from bb %i", bb->index); |
3dec4024 JH |
2524 | err = 1; |
2525 | } | |
a813c111 | 2526 | if (n_fallthru && any_uncondjump_p (BB_END (bb))) |
3dec4024 | 2527 | { |
f99ffaa3 | 2528 | error ("fallthru edge after unconditional jump in bb %i", bb->index); |
3dec4024 JH |
2529 | err = 1; |
2530 | } | |
a813c111 | 2531 | if (n_branch != 1 && any_uncondjump_p (BB_END (bb))) |
3dec4024 | 2532 | { |
f99ffaa3 EB |
2533 | error ("wrong number of branch edges after unconditional jump" |
2534 | " in bb %i", bb->index); | |
3dec4024 JH |
2535 | err = 1; |
2536 | } | |
a813c111 | 2537 | if (n_branch != 1 && any_condjump_p (BB_END (bb)) |
c11fd0b2 | 2538 | && JUMP_LABEL (BB_END (bb)) != BB_HEAD (fallthru->dest)) |
3dec4024 | 2539 | { |
f99ffaa3 EB |
2540 | error ("wrong amount of branch edges after conditional jump" |
2541 | " in bb %i", bb->index); | |
2542 | err = 1; | |
2543 | } | |
2544 | if (n_abnormal_call && !CALL_P (BB_END (bb))) | |
2545 | { | |
2546 | error ("abnormal call edges for non-call insn in bb %i", bb->index); | |
3dec4024 JH |
2547 | err = 1; |
2548 | } | |
f99ffaa3 | 2549 | if (n_sibcall && !CALL_P (BB_END (bb))) |
3dec4024 | 2550 | { |
f99ffaa3 | 2551 | error ("sibcall edges for non-call insn in bb %i", bb->index); |
3dec4024 JH |
2552 | err = 1; |
2553 | } | |
f99ffaa3 EB |
2554 | if (n_abnormal > n_eh |
2555 | && !(CALL_P (BB_END (bb)) | |
2556 | && n_abnormal == n_abnormal_call + n_sibcall) | |
4b4bf941 | 2557 | && (!JUMP_P (BB_END (bb)) |
a813c111 SB |
2558 | || any_condjump_p (BB_END (bb)) |
2559 | || any_uncondjump_p (BB_END (bb)))) | |
3dec4024 | 2560 | { |
ab532386 | 2561 | error ("abnormal edges for no purpose in bb %i", bb->index); |
3dec4024 JH |
2562 | err = 1; |
2563 | } | |
251a41b9 | 2564 | } |
f87c27b4 | 2565 | |
600b5b1d TJ |
2566 | /* If there are partitions, do a sanity check on them: A basic block in |
2567 | a cold partition cannot dominate a basic block in a hot partition. */ | |
2568 | if (crtl->has_bb_partition && !err) | |
2569 | { | |
2570 | vec<basic_block> bbs_to_fix = find_partition_fixes (true); | |
2571 | err = !bbs_to_fix.is_empty (); | |
2572 | } | |
2573 | ||
251a41b9 TJ |
2574 | /* Clean up. */ |
2575 | return err; | |
2576 | } | |
5f0d2358 | 2577 | |
251a41b9 TJ |
2578 | /* Checks on the instructions within blocks. Currently checks that each |
2579 | block starts with a basic block note, and that basic block notes and | |
2580 | control flow jumps are not found in the middle of the block. */ | |
ca6c03ca | 2581 | |
251a41b9 TJ |
2582 | static int |
2583 | rtl_verify_bb_insns (void) | |
2584 | { | |
2585 | rtx x; | |
2586 | int err = 0; | |
2587 | basic_block bb; | |
2588 | ||
4f42035e | 2589 | FOR_EACH_BB_REVERSE_FN (bb, cfun) |
251a41b9 TJ |
2590 | { |
2591 | /* Now check the header of basic | |
c22cacf3 | 2592 | block. It ought to contain optional CODE_LABEL followed |
ca6c03ca | 2593 | by NOTE_BASIC_BLOCK. */ |
a813c111 | 2594 | x = BB_HEAD (bb); |
4b4bf941 | 2595 | if (LABEL_P (x)) |
ca6c03ca | 2596 | { |
a813c111 | 2597 | if (BB_END (bb) == x) |
ca6c03ca JH |
2598 | { |
2599 | error ("NOTE_INSN_BASIC_BLOCK is missing for block %d", | |
0b17ab2f | 2600 | bb->index); |
ca6c03ca JH |
2601 | err = 1; |
2602 | } | |
5f0d2358 | 2603 | |
ca6c03ca JH |
2604 | x = NEXT_INSN (x); |
2605 | } | |
5f0d2358 | 2606 | |
ca6c03ca JH |
2607 | if (!NOTE_INSN_BASIC_BLOCK_P (x) || NOTE_BASIC_BLOCK (x) != bb) |
2608 | { | |
2609 | error ("NOTE_INSN_BASIC_BLOCK is missing for block %d", | |
0b17ab2f | 2610 | bb->index); |
ca6c03ca JH |
2611 | err = 1; |
2612 | } | |
2613 | ||
a813c111 | 2614 | if (BB_END (bb) == x) |
49243025 | 2615 | /* Do checks for empty blocks here. */ |
5f0d2358 | 2616 | ; |
ca6c03ca | 2617 | else |
5f0d2358 RK |
2618 | for (x = NEXT_INSN (x); x; x = NEXT_INSN (x)) |
2619 | { | |
2620 | if (NOTE_INSN_BASIC_BLOCK_P (x)) | |
2621 | { | |
2622 | error ("NOTE_INSN_BASIC_BLOCK %d in middle of basic block %d", | |
0b17ab2f | 2623 | INSN_UID (x), bb->index); |
5f0d2358 RK |
2624 | err = 1; |
2625 | } | |
2626 | ||
a813c111 | 2627 | if (x == BB_END (bb)) |
5f0d2358 | 2628 | break; |
ca6c03ca | 2629 | |
83fd323c | 2630 | if (control_flow_insn_p (x)) |
5f0d2358 | 2631 | { |
0b17ab2f | 2632 | error ("in basic block %d:", bb->index); |
5f0d2358 RK |
2633 | fatal_insn ("flow control insn inside a basic block", x); |
2634 | } | |
2635 | } | |
ca6c03ca JH |
2636 | } |
2637 | ||
251a41b9 TJ |
2638 | /* Clean up. */ |
2639 | return err; | |
2640 | } | |
2641 | ||
2642 | /* Verify that block pointers for instructions in basic blocks, headers and | |
2643 | footers are set appropriately. */ | |
2644 | ||
2645 | static int | |
2646 | rtl_verify_bb_pointers (void) | |
2647 | { | |
2648 | int err = 0; | |
2649 | basic_block bb; | |
2650 | ||
2651 | /* Check the general integrity of the basic blocks. */ | |
4f42035e | 2652 | FOR_EACH_BB_REVERSE_FN (bb, cfun) |
251a41b9 TJ |
2653 | { |
2654 | rtx insn; | |
2655 | ||
2656 | if (!(bb->flags & BB_RTL)) | |
2657 | { | |
2658 | error ("BB_RTL flag not set for block %d", bb->index); | |
2659 | err = 1; | |
2660 | } | |
2661 | ||
2662 | FOR_BB_INSNS (bb, insn) | |
2663 | if (BLOCK_FOR_INSN (insn) != bb) | |
2664 | { | |
2665 | error ("insn %d basic block pointer is %d, should be %d", | |
2666 | INSN_UID (insn), | |
2667 | BLOCK_FOR_INSN (insn) ? BLOCK_FOR_INSN (insn)->index : 0, | |
2668 | bb->index); | |
2669 | err = 1; | |
2670 | } | |
2671 | ||
2672 | for (insn = BB_HEADER (bb); insn; insn = NEXT_INSN (insn)) | |
2673 | if (!BARRIER_P (insn) | |
2674 | && BLOCK_FOR_INSN (insn) != NULL) | |
2675 | { | |
2676 | error ("insn %d in header of bb %d has non-NULL basic block", | |
2677 | INSN_UID (insn), bb->index); | |
2678 | err = 1; | |
2679 | } | |
2680 | for (insn = BB_FOOTER (bb); insn; insn = NEXT_INSN (insn)) | |
2681 | if (!BARRIER_P (insn) | |
2682 | && BLOCK_FOR_INSN (insn) != NULL) | |
2683 | { | |
2684 | error ("insn %d in footer of bb %d has non-NULL basic block", | |
2685 | INSN_UID (insn), bb->index); | |
2686 | err = 1; | |
2687 | } | |
2688 | } | |
af205f67 | 2689 | |
10e9fecc | 2690 | /* Clean up. */ |
10e9fecc JH |
2691 | return err; |
2692 | } | |
5f0d2358 | 2693 | |
10e9fecc JH |
2694 | /* Verify the CFG and RTL consistency common for both underlying RTL and |
2695 | cfglayout RTL. | |
5f0d2358 | 2696 | |
10e9fecc | 2697 | Currently it does following checks: |
251a41b9 TJ |
2698 | |
2699 | - overlapping of basic blocks | |
2700 | - insns with wrong BLOCK_FOR_INSN pointers | |
2701 | - headers of basic blocks (the NOTE_INSN_BASIC_BLOCK note) | |
2702 | - tails of basic blocks (ensure that boundary is necessary) | |
2703 | - scans body of the basic block for JUMP_INSN, CODE_LABEL | |
2704 | and NOTE_INSN_BASIC_BLOCK | |
2705 | - verify that no fall_thru edge crosses hot/cold partition boundaries | |
2706 | - verify that there are no pending RTL branch predictions | |
600b5b1d | 2707 | - verify that hot blocks are not dominated by cold blocks |
251a41b9 TJ |
2708 | |
2709 | In future it can be extended check a lot of other stuff as well | |
2710 | (reachability of basic blocks, life information, etc. etc.). */ | |
9eab6785 | 2711 | |
10e9fecc | 2712 | static int |
251a41b9 TJ |
2713 | rtl_verify_flow_info_1 (void) |
2714 | { | |
2715 | int err = 0; | |
2716 | ||
2717 | err |= rtl_verify_bb_pointers (); | |
2718 | ||
2719 | err |= rtl_verify_bb_insns (); | |
2720 | ||
2721 | err |= rtl_verify_edges (); | |
2722 | ||
251a41b9 TJ |
2723 | return err; |
2724 | } | |
2725 | ||
2726 | /* Walk the instruction chain and verify that bb head/end pointers | |
2727 | are correct, and that instructions are in exactly one bb and have | |
2728 | correct block pointers. */ | |
2729 | ||
2730 | static int | |
2731 | rtl_verify_bb_insn_chain (void) | |
10e9fecc JH |
2732 | { |
2733 | basic_block bb; | |
251a41b9 | 2734 | int err = 0; |
10e9fecc | 2735 | rtx x; |
9eab6785 SB |
2736 | rtx last_head = get_last_insn (); |
2737 | basic_block *bb_info; | |
9eab6785 SB |
2738 | const int max_uid = get_max_uid (); |
2739 | ||
2740 | bb_info = XCNEWVEC (basic_block, max_uid); | |
ca6c03ca | 2741 | |
4f42035e | 2742 | FOR_EACH_BB_REVERSE_FN (bb, cfun) |
10e9fecc | 2743 | { |
9eab6785 SB |
2744 | rtx head = BB_HEAD (bb); |
2745 | rtx end = BB_END (bb); | |
628f6a4e | 2746 | |
9eab6785 | 2747 | for (x = last_head; x != NULL_RTX; x = PREV_INSN (x)) |
a7b87f73 ZD |
2748 | { |
2749 | /* Verify the end of the basic block is in the INSN chain. */ | |
2750 | if (x == end) | |
2751 | break; | |
2752 | ||
251a41b9 TJ |
2753 | /* And that the code outside of basic blocks has NULL bb field. */ |
2754 | if (!BARRIER_P (x) | |
2755 | && BLOCK_FOR_INSN (x) != NULL) | |
2756 | { | |
2757 | error ("insn %d outside of basic blocks has non-NULL bb field", | |
2758 | INSN_UID (x)); | |
2759 | err = 1; | |
2760 | } | |
a7b87f73 | 2761 | } |
9eab6785 SB |
2762 | |
2763 | if (!x) | |
2764 | { | |
2765 | error ("end insn %d for block %d not found in the insn stream", | |
2766 | INSN_UID (end), bb->index); | |
2767 | err = 1; | |
2768 | } | |
2769 | ||
2770 | /* Work backwards from the end to the head of the basic block | |
2771 | to verify the head is in the RTL chain. */ | |
2772 | for (; x != NULL_RTX; x = PREV_INSN (x)) | |
a00d11f0 | 2773 | { |
9eab6785 SB |
2774 | /* While walking over the insn chain, verify insns appear |
2775 | in only one basic block. */ | |
2776 | if (bb_info[INSN_UID (x)] != NULL) | |
2777 | { | |
2778 | error ("insn %d is in multiple basic blocks (%d and %d)", | |
2779 | INSN_UID (x), bb->index, bb_info[INSN_UID (x)]->index); | |
2780 | err = 1; | |
2781 | } | |
2782 | ||
2783 | bb_info[INSN_UID (x)] = bb; | |
2784 | ||
2785 | if (x == head) | |
2786 | break; | |
2787 | } | |
2788 | if (!x) | |
2789 | { | |
2790 | error ("head insn %d for block %d not found in the insn stream", | |
2791 | INSN_UID (head), bb->index); | |
a00d11f0 JH |
2792 | err = 1; |
2793 | } | |
2794 | ||
a7b87f73 | 2795 | last_head = PREV_INSN (x); |
251a41b9 TJ |
2796 | } |
2797 | ||
2798 | for (x = last_head; x != NULL_RTX; x = PREV_INSN (x)) | |
2799 | { | |
2800 | /* Check that the code before the first basic block has NULL | |
2801 | bb field. */ | |
2802 | if (!BARRIER_P (x) | |
2803 | && BLOCK_FOR_INSN (x) != NULL) | |
2804 | { | |
2805 | error ("insn %d outside of basic blocks has non-NULL bb field", | |
2806 | INSN_UID (x)); | |
2807 | err = 1; | |
2808 | } | |
2809 | } | |
2810 | free (bb_info); | |
2811 | ||
2812 | return err; | |
2813 | } | |
2814 | ||
2815 | /* Verify that fallthru edges point to adjacent blocks in layout order and | |
2816 | that barriers exist after non-fallthru blocks. */ | |
2817 | ||
2818 | static int | |
2819 | rtl_verify_fallthru (void) | |
2820 | { | |
2821 | basic_block bb; | |
2822 | int err = 0; | |
2823 | ||
4f42035e | 2824 | FOR_EACH_BB_REVERSE_FN (bb, cfun) |
251a41b9 TJ |
2825 | { |
2826 | edge e; | |
9eab6785 | 2827 | |
0fd4b31d | 2828 | e = find_fallthru_edge (bb->succs); |
10e9fecc JH |
2829 | if (!e) |
2830 | { | |
2831 | rtx insn; | |
2832 | ||
2833 | /* Ensure existence of barrier in BB with no fallthru edges. */ | |
468059bc DD |
2834 | for (insn = NEXT_INSN (BB_END (bb)); ; insn = NEXT_INSN (insn)) |
2835 | { | |
2836 | if (!insn || NOTE_INSN_BASIC_BLOCK_P (insn)) | |
10e9fecc JH |
2837 | { |
2838 | error ("missing barrier after block %i", bb->index); | |
2839 | err = 1; | |
2840 | break; | |
2841 | } | |
468059bc DD |
2842 | if (BARRIER_P (insn)) |
2843 | break; | |
2844 | } | |
10e9fecc | 2845 | } |
fefa31b5 DM |
2846 | else if (e->src != ENTRY_BLOCK_PTR_FOR_FN (cfun) |
2847 | && e->dest != EXIT_BLOCK_PTR_FOR_FN (cfun)) | |
c22cacf3 | 2848 | { |
10e9fecc JH |
2849 | rtx insn; |
2850 | ||
2851 | if (e->src->next_bb != e->dest) | |
2852 | { | |
2853 | error | |
2854 | ("verify_flow_info: Incorrect blocks for fallthru %i->%i", | |
2855 | e->src->index, e->dest->index); | |
2856 | err = 1; | |
2857 | } | |
2858 | else | |
a813c111 | 2859 | for (insn = NEXT_INSN (BB_END (e->src)); insn != BB_HEAD (e->dest); |
10e9fecc | 2860 | insn = NEXT_INSN (insn)) |
6be85b25 | 2861 | if (BARRIER_P (insn) || INSN_P (insn)) |
10e9fecc JH |
2862 | { |
2863 | error ("verify_flow_info: Incorrect fallthru %i->%i", | |
2864 | e->src->index, e->dest->index); | |
2865 | fatal_insn ("wrong insn in the fallthru edge", insn); | |
2866 | err = 1; | |
2867 | } | |
c22cacf3 | 2868 | } |
10e9fecc | 2869 | } |
ca6c03ca | 2870 | |
251a41b9 TJ |
2871 | return err; |
2872 | } | |
2873 | ||
2874 | /* Verify that blocks are laid out in consecutive order. While walking the | |
2875 | instructions, verify that all expected instructions are inside the basic | |
2876 | blocks, and that all returns are followed by barriers. */ | |
2877 | ||
2878 | static int | |
2879 | rtl_verify_bb_layout (void) | |
2880 | { | |
2881 | basic_block bb; | |
2882 | int err = 0; | |
2883 | rtx x; | |
2884 | int num_bb_notes; | |
2885 | const rtx rtx_first = get_insns (); | |
fefa31b5 | 2886 | basic_block last_bb_seen = ENTRY_BLOCK_PTR_FOR_FN (cfun), curr_bb = NULL; |
9eab6785 | 2887 | |
ca6c03ca | 2888 | num_bb_notes = 0; |
fefa31b5 | 2889 | last_bb_seen = ENTRY_BLOCK_PTR_FOR_FN (cfun); |
e0082a72 | 2890 | |
5f0d2358 | 2891 | for (x = rtx_first; x; x = NEXT_INSN (x)) |
ca6c03ca JH |
2892 | { |
2893 | if (NOTE_INSN_BASIC_BLOCK_P (x)) | |
2894 | { | |
bf77398c | 2895 | bb = NOTE_BASIC_BLOCK (x); |
5f0d2358 | 2896 | |
ca6c03ca | 2897 | num_bb_notes++; |
e0082a72 | 2898 | if (bb != last_bb_seen->next_bb) |
10e9fecc | 2899 | internal_error ("basic blocks not laid down consecutively"); |
ca6c03ca | 2900 | |
10e9fecc | 2901 | curr_bb = last_bb_seen = bb; |
ca6c03ca JH |
2902 | } |
2903 | ||
10e9fecc | 2904 | if (!curr_bb) |
ca6c03ca JH |
2905 | { |
2906 | switch (GET_CODE (x)) | |
2907 | { | |
2908 | case BARRIER: | |
2909 | case NOTE: | |
2910 | break; | |
2911 | ||
2912 | case CODE_LABEL: | |
39718607 | 2913 | /* An ADDR_VEC is placed outside any basic block. */ |
ca6c03ca | 2914 | if (NEXT_INSN (x) |
481683e1 | 2915 | && JUMP_TABLE_DATA_P (NEXT_INSN (x))) |
5f0d2358 | 2916 | x = NEXT_INSN (x); |
ca6c03ca JH |
2917 | |
2918 | /* But in any case, non-deletable labels can appear anywhere. */ | |
2919 | break; | |
2920 | ||
2921 | default: | |
1f978f5f | 2922 | fatal_insn ("insn outside basic block", x); |
ca6c03ca JH |
2923 | } |
2924 | } | |
2925 | ||
26cae194 | 2926 | if (JUMP_P (x) |
ca6c03ca | 2927 | && returnjump_p (x) && ! condjump_p (x) |
15eb3a2e | 2928 | && ! (next_nonnote_insn (x) && BARRIER_P (next_nonnote_insn (x)))) |
1f978f5f | 2929 | fatal_insn ("return not followed by barrier", x); |
251a41b9 | 2930 | |
a813c111 | 2931 | if (curr_bb && x == BB_END (curr_bb)) |
10e9fecc | 2932 | curr_bb = NULL; |
ca6c03ca JH |
2933 | } |
2934 | ||
0cae8d31 | 2935 | if (num_bb_notes != n_basic_blocks_for_fn (cfun) - NUM_FIXED_BLOCKS) |
ca6c03ca | 2936 | internal_error |
0b17ab2f | 2937 | ("number of bb notes in insn chain (%d) != n_basic_blocks (%d)", |
0cae8d31 | 2938 | num_bb_notes, n_basic_blocks_for_fn (cfun)); |
ca6c03ca | 2939 | |
10e9fecc | 2940 | return err; |
ca6c03ca | 2941 | } |
251a41b9 TJ |
2942 | |
2943 | /* Verify the CFG and RTL consistency common for both underlying RTL and | |
2944 | cfglayout RTL, plus consistency checks specific to linearized RTL mode. | |
2945 | ||
2946 | Currently it does following checks: | |
2947 | - all checks of rtl_verify_flow_info_1 | |
2948 | - test head/end pointers | |
2949 | - check that blocks are laid out in consecutive order | |
2950 | - check that all insns are in the basic blocks | |
2951 | (except the switch handling code, barriers and notes) | |
2952 | - check that all returns are followed by barriers | |
600b5b1d TJ |
2953 | - check that all fallthru edge points to the adjacent blocks |
2954 | - verify that there is a single hot/cold partition boundary after bbro */ | |
251a41b9 TJ |
2955 | |
2956 | static int | |
2957 | rtl_verify_flow_info (void) | |
2958 | { | |
2959 | int err = 0; | |
2960 | ||
2961 | err |= rtl_verify_flow_info_1 (); | |
2962 | ||
2963 | err |= rtl_verify_bb_insn_chain (); | |
2964 | ||
2965 | err |= rtl_verify_fallthru (); | |
2966 | ||
2967 | err |= rtl_verify_bb_layout (); | |
2968 | ||
3371a64f TJ |
2969 | err |= verify_hot_cold_block_grouping (); |
2970 | ||
251a41b9 TJ |
2971 | return err; |
2972 | } | |
ca6c03ca | 2973 | \f |
eaec9b3d | 2974 | /* Assume that the preceding pass has possibly eliminated jump instructions |
ca6c03ca JH |
2975 | or converted the unconditional jumps. Eliminate the edges from CFG. |
2976 | Return true if any edges are eliminated. */ | |
2977 | ||
2978 | bool | |
d329e058 | 2979 | purge_dead_edges (basic_block bb) |
ca6c03ca | 2980 | { |
628f6a4e | 2981 | edge e; |
a813c111 | 2982 | rtx insn = BB_END (bb), note; |
ca6c03ca | 2983 | bool purged = false; |
628f6a4e BE |
2984 | bool found; |
2985 | edge_iterator ei; | |
ca6c03ca | 2986 | |
b5b8b0ac AO |
2987 | if (DEBUG_INSN_P (insn) && insn != BB_HEAD (bb)) |
2988 | do | |
2989 | insn = PREV_INSN (insn); | |
2990 | while ((DEBUG_INSN_P (insn) || NOTE_P (insn)) && insn != BB_HEAD (bb)); | |
2991 | ||
70da1d03 | 2992 | /* If this instruction cannot trap, remove REG_EH_REGION notes. */ |
4b4bf941 | 2993 | if (NONJUMP_INSN_P (insn) |
70da1d03 JH |
2994 | && (note = find_reg_note (insn, REG_EH_REGION, NULL))) |
2995 | { | |
2996 | rtx eqnote; | |
2997 | ||
2998 | if (! may_trap_p (PATTERN (insn)) | |
2999 | || ((eqnote = find_reg_equal_equiv_note (insn)) | |
3000 | && ! may_trap_p (XEXP (eqnote, 0)))) | |
3001 | remove_note (insn, note); | |
3002 | } | |
3003 | ||
546c093e | 3004 | /* Cleanup abnormal edges caused by exceptions or non-local gotos. */ |
628f6a4e | 3005 | for (ei = ei_start (bb->succs); (e = ei_safe_edge (ei)); ) |
546c093e | 3006 | { |
1d65f45c RH |
3007 | bool remove = false; |
3008 | ||
e5f9a909 JW |
3009 | /* There are three types of edges we need to handle correctly here: EH |
3010 | edges, abnormal call EH edges, and abnormal call non-EH edges. The | |
3011 | latter can appear when nonlocal gotos are used. */ | |
1d65f45c | 3012 | if (e->flags & EDGE_ABNORMAL_CALL) |
546c093e | 3013 | { |
1d65f45c RH |
3014 | if (!CALL_P (insn)) |
3015 | remove = true; | |
3016 | else if (can_nonlocal_goto (insn)) | |
3017 | ; | |
3018 | else if ((e->flags & EDGE_EH) && can_throw_internal (insn)) | |
3019 | ; | |
0a35513e AH |
3020 | else if (flag_tm && find_reg_note (insn, REG_TM, NULL)) |
3021 | ; | |
1d65f45c RH |
3022 | else |
3023 | remove = true; | |
546c093e | 3024 | } |
1d65f45c RH |
3025 | else if (e->flags & EDGE_EH) |
3026 | remove = !can_throw_internal (insn); | |
3027 | ||
3028 | if (remove) | |
546c093e | 3029 | { |
1d65f45c RH |
3030 | remove_edge (e); |
3031 | df_set_bb_dirty (bb); | |
3032 | purged = true; | |
546c093e RH |
3033 | } |
3034 | else | |
1d65f45c | 3035 | ei_next (&ei); |
546c093e | 3036 | } |
5f0d2358 | 3037 | |
4b4bf941 | 3038 | if (JUMP_P (insn)) |
ca6c03ca JH |
3039 | { |
3040 | rtx note; | |
3041 | edge b,f; | |
628f6a4e | 3042 | edge_iterator ei; |
5f0d2358 | 3043 | |
ca6c03ca JH |
3044 | /* We do care only about conditional jumps and simplejumps. */ |
3045 | if (!any_condjump_p (insn) | |
3046 | && !returnjump_p (insn) | |
3047 | && !simplejump_p (insn)) | |
c51d95ec | 3048 | return purged; |
5f0d2358 | 3049 | |
5a1a3e5e JH |
3050 | /* Branch probability/prediction notes are defined only for |
3051 | condjumps. We've possibly turned condjump into simplejump. */ | |
3052 | if (simplejump_p (insn)) | |
3053 | { | |
3054 | note = find_reg_note (insn, REG_BR_PROB, NULL); | |
3055 | if (note) | |
3056 | remove_note (insn, note); | |
3057 | while ((note = find_reg_note (insn, REG_BR_PRED, NULL))) | |
3058 | remove_note (insn, note); | |
3059 | } | |
3060 | ||
628f6a4e | 3061 | for (ei = ei_start (bb->succs); (e = ei_safe_edge (ei)); ) |
ca6c03ca | 3062 | { |
7fcd7218 JH |
3063 | /* Avoid abnormal flags to leak from computed jumps turned |
3064 | into simplejumps. */ | |
f87c27b4 | 3065 | |
0e1638d4 | 3066 | e->flags &= ~EDGE_ABNORMAL; |
7fcd7218 | 3067 | |
5a566bed MM |
3068 | /* See if this edge is one we should keep. */ |
3069 | if ((e->flags & EDGE_FALLTHRU) && any_condjump_p (insn)) | |
3070 | /* A conditional jump can fall through into the next | |
3071 | block, so we should keep the edge. */ | |
628f6a4e BE |
3072 | { |
3073 | ei_next (&ei); | |
3074 | continue; | |
3075 | } | |
fefa31b5 | 3076 | else if (e->dest != EXIT_BLOCK_PTR_FOR_FN (cfun) |
a813c111 | 3077 | && BB_HEAD (e->dest) == JUMP_LABEL (insn)) |
5a566bed MM |
3078 | /* If the destination block is the target of the jump, |
3079 | keep the edge. */ | |
628f6a4e BE |
3080 | { |
3081 | ei_next (&ei); | |
3082 | continue; | |
3083 | } | |
fefa31b5 DM |
3084 | else if (e->dest == EXIT_BLOCK_PTR_FOR_FN (cfun) |
3085 | && returnjump_p (insn)) | |
5a566bed MM |
3086 | /* If the destination block is the exit block, and this |
3087 | instruction is a return, then keep the edge. */ | |
628f6a4e BE |
3088 | { |
3089 | ei_next (&ei); | |
3090 | continue; | |
3091 | } | |
5a566bed MM |
3092 | else if ((e->flags & EDGE_EH) && can_throw_internal (insn)) |
3093 | /* Keep the edges that correspond to exceptions thrown by | |
0b75beaa EB |
3094 | this instruction and rematerialize the EDGE_ABNORMAL |
3095 | flag we just cleared above. */ | |
3096 | { | |
3097 | e->flags |= EDGE_ABNORMAL; | |
628f6a4e | 3098 | ei_next (&ei); |
0b75beaa EB |
3099 | continue; |
3100 | } | |
5f0d2358 | 3101 | |
5a566bed | 3102 | /* We do not need this edge. */ |
6fb5fa3c | 3103 | df_set_bb_dirty (bb); |
ca6c03ca JH |
3104 | purged = true; |
3105 | remove_edge (e); | |
3106 | } | |
5f0d2358 | 3107 | |
628f6a4e | 3108 | if (EDGE_COUNT (bb->succs) == 0 || !purged) |
c51d95ec | 3109 | return purged; |
5f0d2358 | 3110 | |
c263766c RH |
3111 | if (dump_file) |
3112 | fprintf (dump_file, "Purged edges from bb %i\n", bb->index); | |
5f0d2358 | 3113 | |
ca6c03ca JH |
3114 | if (!optimize) |
3115 | return purged; | |
3116 | ||
3117 | /* Redistribute probabilities. */ | |
c5cbcccf | 3118 | if (single_succ_p (bb)) |
ca6c03ca | 3119 | { |
c5cbcccf ZD |
3120 | single_succ_edge (bb)->probability = REG_BR_PROB_BASE; |
3121 | single_succ_edge (bb)->count = bb->count; | |
f87c27b4 | 3122 | } |
ca6c03ca JH |
3123 | else |
3124 | { | |
3125 | note = find_reg_note (insn, REG_BR_PROB, NULL); | |
3126 | if (!note) | |
3127 | return purged; | |
5f0d2358 | 3128 | |
ca6c03ca JH |
3129 | b = BRANCH_EDGE (bb); |
3130 | f = FALLTHRU_EDGE (bb); | |
e5af9ddd | 3131 | b->probability = XINT (note, 0); |
ca6c03ca | 3132 | f->probability = REG_BR_PROB_BASE - b->probability; |
8ddb5a29 | 3133 | /* Update these to use GCOV_COMPUTE_SCALE. */ |
ca6c03ca JH |
3134 | b->count = bb->count * b->probability / REG_BR_PROB_BASE; |
3135 | f->count = bb->count * f->probability / REG_BR_PROB_BASE; | |
3136 | } | |
5f0d2358 | 3137 | |
ca6c03ca JH |
3138 | return purged; |
3139 | } | |
4b4bf941 | 3140 | else if (CALL_P (insn) && SIBLING_CALL_P (insn)) |
1722c2c8 RH |
3141 | { |
3142 | /* First, there should not be any EH or ABCALL edges resulting | |
3143 | from non-local gotos and the like. If there were, we shouldn't | |
3144 | have created the sibcall in the first place. Second, there | |
3145 | should of course never have been a fallthru edge. */ | |
c5cbcccf ZD |
3146 | gcc_assert (single_succ_p (bb)); |
3147 | gcc_assert (single_succ_edge (bb)->flags | |
3148 | == (EDGE_SIBCALL | EDGE_ABNORMAL)); | |
1722c2c8 RH |
3149 | |
3150 | return 0; | |
3151 | } | |
ca6c03ca | 3152 | |
ca6c03ca JH |
3153 | /* If we don't see a jump insn, we don't know exactly why the block would |
3154 | have been broken at this point. Look for a simple, non-fallthru edge, | |
3155 | as these are only created by conditional branches. If we find such an | |
3156 | edge we know that there used to be a jump here and can then safely | |
3157 | remove all non-fallthru edges. */ | |
628f6a4e BE |
3158 | found = false; |
3159 | FOR_EACH_EDGE (e, ei, bb->succs) | |
3160 | if (! (e->flags & (EDGE_COMPLEX | EDGE_FALLTHRU))) | |
3161 | { | |
3162 | found = true; | |
3163 | break; | |
3164 | } | |
5f0d2358 | 3165 | |
628f6a4e | 3166 | if (!found) |
ca6c03ca | 3167 | return purged; |
5f0d2358 | 3168 | |
2afa8dce DB |
3169 | /* Remove all but the fake and fallthru edges. The fake edge may be |
3170 | the only successor for this block in the case of noreturn | |
3171 | calls. */ | |
628f6a4e | 3172 | for (ei = ei_start (bb->succs); (e = ei_safe_edge (ei)); ) |
ca6c03ca | 3173 | { |
2afa8dce | 3174 | if (!(e->flags & (EDGE_FALLTHRU | EDGE_FAKE))) |
c51d95ec | 3175 | { |
6fb5fa3c | 3176 | df_set_bb_dirty (bb); |
c51d95ec JH |
3177 | remove_edge (e); |
3178 | purged = true; | |
3179 | } | |
628f6a4e BE |
3180 | else |
3181 | ei_next (&ei); | |
ca6c03ca | 3182 | } |
5f0d2358 | 3183 | |
c5cbcccf | 3184 | gcc_assert (single_succ_p (bb)); |
5f0d2358 | 3185 | |
c5cbcccf ZD |
3186 | single_succ_edge (bb)->probability = REG_BR_PROB_BASE; |
3187 | single_succ_edge (bb)->count = bb->count; | |
ca6c03ca | 3188 | |
c263766c RH |
3189 | if (dump_file) |
3190 | fprintf (dump_file, "Purged non-fallthru edges from bb %i\n", | |
0b17ab2f | 3191 | bb->index); |
ca6c03ca JH |
3192 | return purged; |
3193 | } | |
3194 | ||
5f0d2358 RK |
3195 | /* Search all basic blocks for potentially dead edges and purge them. Return |
3196 | true if some edge has been eliminated. */ | |
ca6c03ca JH |
3197 | |
3198 | bool | |
25cd19de | 3199 | purge_all_dead_edges (void) |
ca6c03ca | 3200 | { |
e0082a72 | 3201 | int purged = false; |
e0082a72 | 3202 | basic_block bb; |
473fb060 | 3203 | |
11cd3bed | 3204 | FOR_EACH_BB_FN (bb, cfun) |
473fb060 | 3205 | { |
e0082a72 | 3206 | bool purged_here = purge_dead_edges (bb); |
5f0d2358 | 3207 | |
473fb060 | 3208 | purged |= purged_here; |
473fb060 | 3209 | } |
5f0d2358 | 3210 | |
ca6c03ca JH |
3211 | return purged; |
3212 | } | |
9ee634e3 | 3213 | |
ba5e9aca EB |
3214 | /* This is used by a few passes that emit some instructions after abnormal |
3215 | calls, moving the basic block's end, while they in fact do want to emit | |
3216 | them on the fallthru edge. Look for abnormal call edges, find backward | |
3217 | the call in the block and insert the instructions on the edge instead. | |
3218 | ||
3219 | Similarly, handle instructions throwing exceptions internally. | |
3220 | ||
3221 | Return true when instructions have been found and inserted on edges. */ | |
3222 | ||
3223 | bool | |
3224 | fixup_abnormal_edges (void) | |
3225 | { | |
3226 | bool inserted = false; | |
3227 | basic_block bb; | |
3228 | ||
11cd3bed | 3229 | FOR_EACH_BB_FN (bb, cfun) |
ba5e9aca EB |
3230 | { |
3231 | edge e; | |
3232 | edge_iterator ei; | |
3233 | ||
3234 | /* Look for cases we are interested in - calls or instructions causing | |
3235 | exceptions. */ | |
3236 | FOR_EACH_EDGE (e, ei, bb->succs) | |
3237 | if ((e->flags & EDGE_ABNORMAL_CALL) | |
3238 | || ((e->flags & (EDGE_ABNORMAL | EDGE_EH)) | |
3239 | == (EDGE_ABNORMAL | EDGE_EH))) | |
3240 | break; | |
3241 | ||
3242 | if (e && !CALL_P (BB_END (bb)) && !can_throw_internal (BB_END (bb))) | |
3243 | { | |
3244 | rtx insn; | |
3245 | ||
3246 | /* Get past the new insns generated. Allow notes, as the insns | |
3247 | may be already deleted. */ | |
3248 | insn = BB_END (bb); | |
3249 | while ((NONJUMP_INSN_P (insn) || NOTE_P (insn)) | |
3250 | && !can_throw_internal (insn) | |
3251 | && insn != BB_HEAD (bb)) | |
3252 | insn = PREV_INSN (insn); | |
3253 | ||
3254 | if (CALL_P (insn) || can_throw_internal (insn)) | |
3255 | { | |
3256 | rtx stop, next; | |
3257 | ||
3258 | e = find_fallthru_edge (bb->succs); | |
3259 | ||
3260 | stop = NEXT_INSN (BB_END (bb)); | |
3261 | BB_END (bb) = insn; | |
3262 | ||
3263 | for (insn = NEXT_INSN (insn); insn != stop; insn = next) | |
3264 | { | |
3265 | next = NEXT_INSN (insn); | |
3266 | if (INSN_P (insn)) | |
3267 | { | |
3268 | delete_insn (insn); | |
3269 | ||
3270 | /* Sometimes there's still the return value USE. | |
3271 | If it's placed after a trapping call (i.e. that | |
3272 | call is the last insn anyway), we have no fallthru | |
3273 | edge. Simply delete this use and don't try to insert | |
3274 | on the non-existent edge. */ | |
3275 | if (GET_CODE (PATTERN (insn)) != USE) | |
3276 | { | |
3277 | /* We're not deleting it, we're moving it. */ | |
3278 | INSN_DELETED_P (insn) = 0; | |
3279 | PREV_INSN (insn) = NULL_RTX; | |
3280 | NEXT_INSN (insn) = NULL_RTX; | |
3281 | ||
3282 | insert_insn_on_edge (insn, e); | |
3283 | inserted = true; | |
3284 | } | |
3285 | } | |
3286 | else if (!BARRIER_P (insn)) | |
3287 | set_block_for_insn (insn, NULL); | |
3288 | } | |
3289 | } | |
3290 | ||
3291 | /* It may be that we don't find any trapping insn. In this | |
3292 | case we discovered quite late that the insn that had been | |
3293 | marked as can_throw_internal in fact couldn't trap at all. | |
3294 | So we should in fact delete the EH edges out of the block. */ | |
3295 | else | |
3296 | purge_dead_edges (bb); | |
3297 | } | |
3298 | } | |
3299 | ||
3300 | return inserted; | |
3301 | } | |
78bde837 SB |
3302 | \f |
3303 | /* Cut the insns from FIRST to LAST out of the insns stream. */ | |
3304 | ||
3305 | rtx | |
3306 | unlink_insn_chain (rtx first, rtx last) | |
3307 | { | |
3308 | rtx prevfirst = PREV_INSN (first); | |
3309 | rtx nextlast = NEXT_INSN (last); | |
3310 | ||
3311 | PREV_INSN (first) = NULL; | |
3312 | NEXT_INSN (last) = NULL; | |
3313 | if (prevfirst) | |
3314 | NEXT_INSN (prevfirst) = nextlast; | |
3315 | if (nextlast) | |
3316 | PREV_INSN (nextlast) = prevfirst; | |
3317 | else | |
3318 | set_last_insn (prevfirst); | |
3319 | if (!prevfirst) | |
3320 | set_first_insn (nextlast); | |
3321 | return first; | |
3322 | } | |
3323 | \f | |
3324 | /* Skip over inter-block insns occurring after BB which are typically | |
3325 | associated with BB (e.g., barriers). If there are any such insns, | |
3326 | we return the last one. Otherwise, we return the end of BB. */ | |
3327 | ||
3328 | static rtx | |
3329 | skip_insns_after_block (basic_block bb) | |
3330 | { | |
3331 | rtx insn, last_insn, next_head, prev; | |
3332 | ||
3333 | next_head = NULL_RTX; | |
fefa31b5 | 3334 | if (bb->next_bb != EXIT_BLOCK_PTR_FOR_FN (cfun)) |
78bde837 SB |
3335 | next_head = BB_HEAD (bb->next_bb); |
3336 | ||
3337 | for (last_insn = insn = BB_END (bb); (insn = NEXT_INSN (insn)) != 0; ) | |
3338 | { | |
3339 | if (insn == next_head) | |
3340 | break; | |
3341 | ||
3342 | switch (GET_CODE (insn)) | |
3343 | { | |
3344 | case BARRIER: | |
3345 | last_insn = insn; | |
3346 | continue; | |
3347 | ||
3348 | case NOTE: | |
3349 | switch (NOTE_KIND (insn)) | |
3350 | { | |
3351 | case NOTE_INSN_BLOCK_END: | |
3352 | gcc_unreachable (); | |
3353 | continue; | |
3354 | default: | |
3355 | continue; | |
3356 | break; | |
3357 | } | |
3358 | break; | |
3359 | ||
3360 | case CODE_LABEL: | |
3361 | if (NEXT_INSN (insn) | |
3362 | && JUMP_TABLE_DATA_P (NEXT_INSN (insn))) | |
3363 | { | |
3364 | insn = NEXT_INSN (insn); | |
3365 | last_insn = insn; | |
3366 | continue; | |
3367 | } | |
3368 | break; | |
3369 | ||
3370 | default: | |
3371 | break; | |
3372 | } | |
3373 | ||
3374 | break; | |
3375 | } | |
3376 | ||
3377 | /* It is possible to hit contradictory sequence. For instance: | |
3378 | ||
3379 | jump_insn | |
3380 | NOTE_INSN_BLOCK_BEG | |
3381 | barrier | |
3382 | ||
3383 | Where barrier belongs to jump_insn, but the note does not. This can be | |
3384 | created by removing the basic block originally following | |
3385 | NOTE_INSN_BLOCK_BEG. In such case reorder the notes. */ | |
3386 | ||
3387 | for (insn = last_insn; insn != BB_END (bb); insn = prev) | |
3388 | { | |
3389 | prev = PREV_INSN (insn); | |
3390 | if (NOTE_P (insn)) | |
3391 | switch (NOTE_KIND (insn)) | |
3392 | { | |
3393 | case NOTE_INSN_BLOCK_END: | |
3394 | gcc_unreachable (); | |
3395 | break; | |
3396 | case NOTE_INSN_DELETED: | |
3397 | case NOTE_INSN_DELETED_LABEL: | |
3398 | case NOTE_INSN_DELETED_DEBUG_LABEL: | |
3399 | continue; | |
3400 | default: | |
3401 | reorder_insns (insn, insn, last_insn); | |
3402 | } | |
3403 | } | |
3404 | ||
3405 | return last_insn; | |
3406 | } | |
3407 | ||
3408 | /* Locate or create a label for a given basic block. */ | |
3409 | ||
3410 | static rtx | |
3411 | label_for_bb (basic_block bb) | |
3412 | { | |
3413 | rtx label = BB_HEAD (bb); | |
3414 | ||
3415 | if (!LABEL_P (label)) | |
3416 | { | |
3417 | if (dump_file) | |
3418 | fprintf (dump_file, "Emitting label for block %d\n", bb->index); | |
3419 | ||
3420 | label = block_label (bb); | |
3421 | } | |
3422 | ||
3423 | return label; | |
3424 | } | |
3425 | ||
3426 | /* Locate the effective beginning and end of the insn chain for each | |
3427 | block, as defined by skip_insns_after_block above. */ | |
3428 | ||
3429 | static void | |
3430 | record_effective_endpoints (void) | |
3431 | { | |
3432 | rtx next_insn; | |
3433 | basic_block bb; | |
3434 | rtx insn; | |
3435 | ||
3436 | for (insn = get_insns (); | |
3437 | insn | |
3438 | && NOTE_P (insn) | |
3439 | && NOTE_KIND (insn) != NOTE_INSN_BASIC_BLOCK; | |
3440 | insn = NEXT_INSN (insn)) | |
3441 | continue; | |
3442 | /* No basic blocks at all? */ | |
3443 | gcc_assert (insn); | |
3444 | ||
3445 | if (PREV_INSN (insn)) | |
3446 | cfg_layout_function_header = | |
3447 | unlink_insn_chain (get_insns (), PREV_INSN (insn)); | |
3448 | else | |
3449 | cfg_layout_function_header = NULL_RTX; | |
3450 | ||
3451 | next_insn = get_insns (); | |
11cd3bed | 3452 | FOR_EACH_BB_FN (bb, cfun) |
78bde837 SB |
3453 | { |
3454 | rtx end; | |
3455 | ||
3456 | if (PREV_INSN (BB_HEAD (bb)) && next_insn != BB_HEAD (bb)) | |
3457 | BB_HEADER (bb) = unlink_insn_chain (next_insn, | |
3458 | PREV_INSN (BB_HEAD (bb))); | |
3459 | end = skip_insns_after_block (bb); | |
3460 | if (NEXT_INSN (BB_END (bb)) && BB_END (bb) != end) | |
3461 | BB_FOOTER (bb) = unlink_insn_chain (NEXT_INSN (BB_END (bb)), end); | |
3462 | next_insn = NEXT_INSN (BB_END (bb)); | |
3463 | } | |
3464 | ||
3465 | cfg_layout_function_footer = next_insn; | |
3466 | if (cfg_layout_function_footer) | |
3467 | cfg_layout_function_footer = unlink_insn_chain (cfg_layout_function_footer, get_last_insn ()); | |
3468 | } | |
3469 | \f | |
3470 | static unsigned int | |
3471 | into_cfg_layout_mode (void) | |
3472 | { | |
3473 | cfg_layout_initialize (0); | |
3474 | return 0; | |
3475 | } | |
3476 | ||
3477 | static unsigned int | |
3478 | outof_cfg_layout_mode (void) | |
3479 | { | |
3480 | basic_block bb; | |
3481 | ||
11cd3bed | 3482 | FOR_EACH_BB_FN (bb, cfun) |
fefa31b5 | 3483 | if (bb->next_bb != EXIT_BLOCK_PTR_FOR_FN (cfun)) |
78bde837 SB |
3484 | bb->aux = bb->next_bb; |
3485 | ||
3486 | cfg_layout_finalize (); | |
3487 | ||
3488 | return 0; | |
3489 | } | |
3490 | ||
27a4cd48 DM |
3491 | namespace { |
3492 | ||
3493 | const pass_data pass_data_into_cfg_layout_mode = | |
3494 | { | |
3495 | RTL_PASS, /* type */ | |
3496 | "into_cfglayout", /* name */ | |
3497 | OPTGROUP_NONE, /* optinfo_flags */ | |
3498 | false, /* has_gate */ | |
3499 | true, /* has_execute */ | |
3500 | TV_CFG, /* tv_id */ | |
3501 | 0, /* properties_required */ | |
3502 | PROP_cfglayout, /* properties_provided */ | |
3503 | 0, /* properties_destroyed */ | |
3504 | 0, /* todo_flags_start */ | |
3505 | 0, /* todo_flags_finish */ | |
78bde837 SB |
3506 | }; |
3507 | ||
27a4cd48 DM |
3508 | class pass_into_cfg_layout_mode : public rtl_opt_pass |
3509 | { | |
3510 | public: | |
c3284718 RS |
3511 | pass_into_cfg_layout_mode (gcc::context *ctxt) |
3512 | : rtl_opt_pass (pass_data_into_cfg_layout_mode, ctxt) | |
27a4cd48 DM |
3513 | {} |
3514 | ||
3515 | /* opt_pass methods: */ | |
3516 | unsigned int execute () { return into_cfg_layout_mode (); } | |
3517 | ||
3518 | }; // class pass_into_cfg_layout_mode | |
3519 | ||
3520 | } // anon namespace | |
3521 | ||
3522 | rtl_opt_pass * | |
3523 | make_pass_into_cfg_layout_mode (gcc::context *ctxt) | |
3524 | { | |
3525 | return new pass_into_cfg_layout_mode (ctxt); | |
3526 | } | |
3527 | ||
3528 | namespace { | |
3529 | ||
3530 | const pass_data pass_data_outof_cfg_layout_mode = | |
3531 | { | |
3532 | RTL_PASS, /* type */ | |
3533 | "outof_cfglayout", /* name */ | |
3534 | OPTGROUP_NONE, /* optinfo_flags */ | |
3535 | false, /* has_gate */ | |
3536 | true, /* has_execute */ | |
3537 | TV_CFG, /* tv_id */ | |
3538 | 0, /* properties_required */ | |
3539 | 0, /* properties_provided */ | |
3540 | PROP_cfglayout, /* properties_destroyed */ | |
3541 | 0, /* todo_flags_start */ | |
3542 | 0, /* todo_flags_finish */ | |
78bde837 | 3543 | }; |
27a4cd48 DM |
3544 | |
3545 | class pass_outof_cfg_layout_mode : public rtl_opt_pass | |
3546 | { | |
3547 | public: | |
c3284718 RS |
3548 | pass_outof_cfg_layout_mode (gcc::context *ctxt) |
3549 | : rtl_opt_pass (pass_data_outof_cfg_layout_mode, ctxt) | |
27a4cd48 DM |
3550 | {} |
3551 | ||
3552 | /* opt_pass methods: */ | |
3553 | unsigned int execute () { return outof_cfg_layout_mode (); } | |
3554 | ||
3555 | }; // class pass_outof_cfg_layout_mode | |
3556 | ||
3557 | } // anon namespace | |
3558 | ||
3559 | rtl_opt_pass * | |
3560 | make_pass_outof_cfg_layout_mode (gcc::context *ctxt) | |
3561 | { | |
3562 | return new pass_outof_cfg_layout_mode (ctxt); | |
3563 | } | |
78bde837 SB |
3564 | \f |
3565 | ||
3566 | /* Link the basic blocks in the correct order, compacting the basic | |
3567 | block queue while at it. If STAY_IN_CFGLAYOUT_MODE is false, this | |
3568 | function also clears the basic block header and footer fields. | |
3569 | ||
3570 | This function is usually called after a pass (e.g. tracer) finishes | |
3571 | some transformations while in cfglayout mode. The required sequence | |
3572 | of the basic blocks is in a linked list along the bb->aux field. | |
3573 | This functions re-links the basic block prev_bb and next_bb pointers | |
532aafad SB |
3574 | accordingly, and it compacts and renumbers the blocks. |
3575 | ||
3576 | FIXME: This currently works only for RTL, but the only RTL-specific | |
3577 | bits are the STAY_IN_CFGLAYOUT_MODE bits. The tracer pass was moved | |
3578 | to GIMPLE a long time ago, but it doesn't relink the basic block | |
3579 | chain. It could do that (to give better initial RTL) if this function | |
3580 | is made IR-agnostic (and moved to cfganal.c or cfg.c while at it). */ | |
78bde837 SB |
3581 | |
3582 | void | |
3583 | relink_block_chain (bool stay_in_cfglayout_mode) | |
3584 | { | |
3585 | basic_block bb, prev_bb; | |
3586 | int index; | |
3587 | ||
3588 | /* Maybe dump the re-ordered sequence. */ | |
3589 | if (dump_file) | |
3590 | { | |
3591 | fprintf (dump_file, "Reordered sequence:\n"); | |
fefa31b5 DM |
3592 | for (bb = ENTRY_BLOCK_PTR_FOR_FN (cfun)->next_bb, index = |
3593 | NUM_FIXED_BLOCKS; | |
78bde837 SB |
3594 | bb; |
3595 | bb = (basic_block) bb->aux, index++) | |
3596 | { | |
3597 | fprintf (dump_file, " %i ", index); | |
3598 | if (get_bb_original (bb)) | |
3599 | fprintf (dump_file, "duplicate of %i ", | |
3600 | get_bb_original (bb)->index); | |
3601 | else if (forwarder_block_p (bb) | |
3602 | && !LABEL_P (BB_HEAD (bb))) | |
3603 | fprintf (dump_file, "compensation "); | |
3604 | else | |
3605 | fprintf (dump_file, "bb %i ", bb->index); | |
3606 | fprintf (dump_file, " [%i]\n", bb->frequency); | |
3607 | } | |
3608 | } | |
3609 | ||
3610 | /* Now reorder the blocks. */ | |
fefa31b5 DM |
3611 | prev_bb = ENTRY_BLOCK_PTR_FOR_FN (cfun); |
3612 | bb = ENTRY_BLOCK_PTR_FOR_FN (cfun)->next_bb; | |
78bde837 SB |
3613 | for (; bb; prev_bb = bb, bb = (basic_block) bb->aux) |
3614 | { | |
3615 | bb->prev_bb = prev_bb; | |
3616 | prev_bb->next_bb = bb; | |
3617 | } | |
fefa31b5 DM |
3618 | prev_bb->next_bb = EXIT_BLOCK_PTR_FOR_FN (cfun); |
3619 | EXIT_BLOCK_PTR_FOR_FN (cfun)->prev_bb = prev_bb; | |
78bde837 SB |
3620 | |
3621 | /* Then, clean up the aux fields. */ | |
04a90bec | 3622 | FOR_ALL_BB_FN (bb, cfun) |
78bde837 SB |
3623 | { |
3624 | bb->aux = NULL; | |
3625 | if (!stay_in_cfglayout_mode) | |
3626 | BB_HEADER (bb) = BB_FOOTER (bb) = NULL; | |
3627 | } | |
3628 | ||
3629 | /* Maybe reset the original copy tables, they are not valid anymore | |
3630 | when we renumber the basic blocks in compact_blocks. If we are | |
3631 | are going out of cfglayout mode, don't re-allocate the tables. */ | |
3632 | free_original_copy_tables (); | |
3633 | if (stay_in_cfglayout_mode) | |
3634 | initialize_original_copy_tables (); | |
3635 | ||
3636 | /* Finally, put basic_block_info in the new order. */ | |
3637 | compact_blocks (); | |
3638 | } | |
3639 | \f | |
3640 | ||
3641 | /* Given a reorder chain, rearrange the code to match. */ | |
3642 | ||
3643 | static void | |
3644 | fixup_reorder_chain (void) | |
3645 | { | |
3646 | basic_block bb; | |
3647 | rtx insn = NULL; | |
3648 | ||
3649 | if (cfg_layout_function_header) | |
3650 | { | |
3651 | set_first_insn (cfg_layout_function_header); | |
3652 | insn = cfg_layout_function_header; | |
3653 | while (NEXT_INSN (insn)) | |
3654 | insn = NEXT_INSN (insn); | |
3655 | } | |
3656 | ||
3657 | /* First do the bulk reordering -- rechain the blocks without regard to | |
3658 | the needed changes to jumps and labels. */ | |
3659 | ||
fefa31b5 DM |
3660 | for (bb = ENTRY_BLOCK_PTR_FOR_FN (cfun)->next_bb; bb; bb = (basic_block) |
3661 | bb->aux) | |
78bde837 SB |
3662 | { |
3663 | if (BB_HEADER (bb)) | |
3664 | { | |
3665 | if (insn) | |
3666 | NEXT_INSN (insn) = BB_HEADER (bb); | |
3667 | else | |
3668 | set_first_insn (BB_HEADER (bb)); | |
3669 | PREV_INSN (BB_HEADER (bb)) = insn; | |
3670 | insn = BB_HEADER (bb); | |
3671 | while (NEXT_INSN (insn)) | |
3672 | insn = NEXT_INSN (insn); | |
3673 | } | |
3674 | if (insn) | |
3675 | NEXT_INSN (insn) = BB_HEAD (bb); | |
3676 | else | |
3677 | set_first_insn (BB_HEAD (bb)); | |
3678 | PREV_INSN (BB_HEAD (bb)) = insn; | |
3679 | insn = BB_END (bb); | |
3680 | if (BB_FOOTER (bb)) | |
3681 | { | |
3682 | NEXT_INSN (insn) = BB_FOOTER (bb); | |
3683 | PREV_INSN (BB_FOOTER (bb)) = insn; | |
3684 | while (NEXT_INSN (insn)) | |
3685 | insn = NEXT_INSN (insn); | |
3686 | } | |
3687 | } | |
3688 | ||
3689 | NEXT_INSN (insn) = cfg_layout_function_footer; | |
3690 | if (cfg_layout_function_footer) | |
3691 | PREV_INSN (cfg_layout_function_footer) = insn; | |
3692 | ||
3693 | while (NEXT_INSN (insn)) | |
3694 | insn = NEXT_INSN (insn); | |
3695 | ||
3696 | set_last_insn (insn); | |
3697 | #ifdef ENABLE_CHECKING | |
3698 | verify_insn_chain (); | |
3699 | #endif | |
3700 | ||
3701 | /* Now add jumps and labels as needed to match the blocks new | |
29f3fd5b | 3702 | outgoing edges. */ |
78bde837 | 3703 | |
29f3fd5b SB |
3704 | for (bb = ENTRY_BLOCK_PTR_FOR_FN (cfun)->next_bb; bb ; bb = (basic_block) |
3705 | bb->aux) | |
78bde837 SB |
3706 | { |
3707 | edge e_fall, e_taken, e; | |
3708 | rtx bb_end_insn; | |
3709 | rtx ret_label = NULL_RTX; | |
3371a64f | 3710 | basic_block nb; |
78bde837 SB |
3711 | edge_iterator ei; |
3712 | ||
3713 | if (EDGE_COUNT (bb->succs) == 0) | |
3714 | continue; | |
3715 | ||
3716 | /* Find the old fallthru edge, and another non-EH edge for | |
3717 | a taken jump. */ | |
3718 | e_taken = e_fall = NULL; | |
3719 | ||
3720 | FOR_EACH_EDGE (e, ei, bb->succs) | |
3721 | if (e->flags & EDGE_FALLTHRU) | |
3722 | e_fall = e; | |
3723 | else if (! (e->flags & EDGE_EH)) | |
3724 | e_taken = e; | |
3725 | ||
3726 | bb_end_insn = BB_END (bb); | |
3727 | if (JUMP_P (bb_end_insn)) | |
3728 | { | |
3729 | ret_label = JUMP_LABEL (bb_end_insn); | |
3730 | if (any_condjump_p (bb_end_insn)) | |
3731 | { | |
3732 | /* This might happen if the conditional jump has side | |
3733 | effects and could therefore not be optimized away. | |
3734 | Make the basic block to end with a barrier in order | |
3735 | to prevent rtl_verify_flow_info from complaining. */ | |
3736 | if (!e_fall) | |
3737 | { | |
3738 | gcc_assert (!onlyjump_p (bb_end_insn) | |
3739 | || returnjump_p (bb_end_insn)); | |
39718607 | 3740 | emit_barrier_after (bb_end_insn); |
78bde837 SB |
3741 | continue; |
3742 | } | |
3743 | ||
3744 | /* If the old fallthru is still next, nothing to do. */ | |
3745 | if (bb->aux == e_fall->dest | |
fefa31b5 | 3746 | || e_fall->dest == EXIT_BLOCK_PTR_FOR_FN (cfun)) |
78bde837 SB |
3747 | continue; |
3748 | ||
3749 | /* The degenerated case of conditional jump jumping to the next | |
3750 | instruction can happen for jumps with side effects. We need | |
3751 | to construct a forwarder block and this will be done just | |
3752 | fine by force_nonfallthru below. */ | |
3753 | if (!e_taken) | |
3754 | ; | |
3755 | ||
3756 | /* There is another special case: if *neither* block is next, | |
3757 | such as happens at the very end of a function, then we'll | |
3758 | need to add a new unconditional jump. Choose the taken | |
3759 | edge based on known or assumed probability. */ | |
3760 | else if (bb->aux != e_taken->dest) | |
3761 | { | |
3762 | rtx note = find_reg_note (bb_end_insn, REG_BR_PROB, 0); | |
3763 | ||
3764 | if (note | |
e5af9ddd | 3765 | && XINT (note, 0) < REG_BR_PROB_BASE / 2 |
78bde837 | 3766 | && invert_jump (bb_end_insn, |
fefa31b5 DM |
3767 | (e_fall->dest |
3768 | == EXIT_BLOCK_PTR_FOR_FN (cfun) | |
78bde837 SB |
3769 | ? NULL_RTX |
3770 | : label_for_bb (e_fall->dest)), 0)) | |
3771 | { | |
3772 | e_fall->flags &= ~EDGE_FALLTHRU; | |
3773 | gcc_checking_assert (could_fall_through | |
3774 | (e_taken->src, e_taken->dest)); | |
3775 | e_taken->flags |= EDGE_FALLTHRU; | |
3776 | update_br_prob_note (bb); | |
3777 | e = e_fall, e_fall = e_taken, e_taken = e; | |
3778 | } | |
3779 | } | |
3780 | ||
3781 | /* If the "jumping" edge is a crossing edge, and the fall | |
3782 | through edge is non-crossing, leave things as they are. */ | |
3783 | else if ((e_taken->flags & EDGE_CROSSING) | |
3784 | && !(e_fall->flags & EDGE_CROSSING)) | |
3785 | continue; | |
3786 | ||
3787 | /* Otherwise we can try to invert the jump. This will | |
3788 | basically never fail, however, keep up the pretense. */ | |
3789 | else if (invert_jump (bb_end_insn, | |
fefa31b5 DM |
3790 | (e_fall->dest |
3791 | == EXIT_BLOCK_PTR_FOR_FN (cfun) | |
78bde837 SB |
3792 | ? NULL_RTX |
3793 | : label_for_bb (e_fall->dest)), 0)) | |
3794 | { | |
3795 | e_fall->flags &= ~EDGE_FALLTHRU; | |
3796 | gcc_checking_assert (could_fall_through | |
3797 | (e_taken->src, e_taken->dest)); | |
3798 | e_taken->flags |= EDGE_FALLTHRU; | |
3799 | update_br_prob_note (bb); | |
3800 | if (LABEL_NUSES (ret_label) == 0 | |
3801 | && single_pred_p (e_taken->dest)) | |
3802 | delete_insn (ret_label); | |
3803 | continue; | |
3804 | } | |
3805 | } | |
3806 | else if (extract_asm_operands (PATTERN (bb_end_insn)) != NULL) | |
3807 | { | |
3808 | /* If the old fallthru is still next or if | |
3809 | asm goto doesn't have a fallthru (e.g. when followed by | |
3810 | __builtin_unreachable ()), nothing to do. */ | |
3811 | if (! e_fall | |
3812 | || bb->aux == e_fall->dest | |
fefa31b5 | 3813 | || e_fall->dest == EXIT_BLOCK_PTR_FOR_FN (cfun)) |
78bde837 SB |
3814 | continue; |
3815 | ||
3816 | /* Otherwise we'll have to use the fallthru fixup below. */ | |
3817 | } | |
3818 | else | |
3819 | { | |
3820 | /* Otherwise we have some return, switch or computed | |
3821 | jump. In the 99% case, there should not have been a | |
3822 | fallthru edge. */ | |
3823 | gcc_assert (returnjump_p (bb_end_insn) || !e_fall); | |
3824 | continue; | |
3825 | } | |
3826 | } | |
3827 | else | |
3828 | { | |
3829 | /* No fallthru implies a noreturn function with EH edges, or | |
3830 | something similarly bizarre. In any case, we don't need to | |
3831 | do anything. */ | |
3832 | if (! e_fall) | |
3833 | continue; | |
3834 | ||
3835 | /* If the fallthru block is still next, nothing to do. */ | |
3836 | if (bb->aux == e_fall->dest) | |
3837 | continue; | |
3838 | ||
3839 | /* A fallthru to exit block. */ | |
fefa31b5 | 3840 | if (e_fall->dest == EXIT_BLOCK_PTR_FOR_FN (cfun)) |
78bde837 SB |
3841 | continue; |
3842 | } | |
3843 | ||
3844 | /* We got here if we need to add a new jump insn. | |
3845 | Note force_nonfallthru can delete E_FALL and thus we have to | |
3846 | save E_FALL->src prior to the call to force_nonfallthru. */ | |
78bde837 SB |
3847 | nb = force_nonfallthru_and_redirect (e_fall, e_fall->dest, ret_label); |
3848 | if (nb) | |
3849 | { | |
3850 | nb->aux = bb->aux; | |
3851 | bb->aux = nb; | |
3852 | /* Don't process this new block. */ | |
3853 | bb = nb; | |
78bde837 SB |
3854 | } |
3855 | } | |
3856 | ||
3857 | relink_block_chain (/*stay_in_cfglayout_mode=*/false); | |
3858 | ||
29f3fd5b | 3859 | /* Annoying special case - jump around dead jumptables left in the code. */ |
11cd3bed | 3860 | FOR_EACH_BB_FN (bb, cfun) |
78bde837 SB |
3861 | { |
3862 | edge e = find_fallthru_edge (bb->succs); | |
3863 | ||
29f3fd5b SB |
3864 | if (e && !can_fallthru (e->src, e->dest)) |
3865 | force_nonfallthru (e); | |
78bde837 SB |
3866 | } |
3867 | ||
3868 | /* Ensure goto_locus from edges has some instructions with that locus | |
3869 | in RTL. */ | |
3870 | if (!optimize) | |
11cd3bed | 3871 | FOR_EACH_BB_FN (bb, cfun) |
78bde837 SB |
3872 | { |
3873 | edge e; | |
3874 | edge_iterator ei; | |
3875 | ||
3876 | FOR_EACH_EDGE (e, ei, bb->succs) | |
2f13f2de | 3877 | if (LOCATION_LOCUS (e->goto_locus) != UNKNOWN_LOCATION |
5368224f | 3878 | && !(e->flags & EDGE_ABNORMAL)) |
78bde837 SB |
3879 | { |
3880 | edge e2; | |
3881 | edge_iterator ei2; | |
3882 | basic_block dest, nb; | |
3883 | rtx end; | |
3884 | ||
3885 | insn = BB_END (e->src); | |
3886 | end = PREV_INSN (BB_HEAD (e->src)); | |
3887 | while (insn != end | |
5368224f | 3888 | && (!NONDEBUG_INSN_P (insn) || !INSN_HAS_LOCATION (insn))) |
78bde837 SB |
3889 | insn = PREV_INSN (insn); |
3890 | if (insn != end | |
5368224f | 3891 | && INSN_LOCATION (insn) == e->goto_locus) |
78bde837 SB |
3892 | continue; |
3893 | if (simplejump_p (BB_END (e->src)) | |
5368224f | 3894 | && !INSN_HAS_LOCATION (BB_END (e->src))) |
78bde837 | 3895 | { |
5368224f | 3896 | INSN_LOCATION (BB_END (e->src)) = e->goto_locus; |
78bde837 SB |
3897 | continue; |
3898 | } | |
3899 | dest = e->dest; | |
fefa31b5 | 3900 | if (dest == EXIT_BLOCK_PTR_FOR_FN (cfun)) |
78bde837 SB |
3901 | { |
3902 | /* Non-fallthru edges to the exit block cannot be split. */ | |
3903 | if (!(e->flags & EDGE_FALLTHRU)) | |
3904 | continue; | |
3905 | } | |
3906 | else | |
3907 | { | |
3908 | insn = BB_HEAD (dest); | |
3909 | end = NEXT_INSN (BB_END (dest)); | |
3910 | while (insn != end && !NONDEBUG_INSN_P (insn)) | |
3911 | insn = NEXT_INSN (insn); | |
5368224f DC |
3912 | if (insn != end && INSN_HAS_LOCATION (insn) |
3913 | && INSN_LOCATION (insn) == e->goto_locus) | |
78bde837 SB |
3914 | continue; |
3915 | } | |
3916 | nb = split_edge (e); | |
3917 | if (!INSN_P (BB_END (nb))) | |
3918 | BB_END (nb) = emit_insn_after_noloc (gen_nop (), BB_END (nb), | |
3919 | nb); | |
5368224f | 3920 | INSN_LOCATION (BB_END (nb)) = e->goto_locus; |
78bde837 SB |
3921 | |
3922 | /* If there are other incoming edges to the destination block | |
3923 | with the same goto locus, redirect them to the new block as | |
3924 | well, this can prevent other such blocks from being created | |
3925 | in subsequent iterations of the loop. */ | |
3926 | for (ei2 = ei_start (dest->preds); (e2 = ei_safe_edge (ei2)); ) | |
2f13f2de | 3927 | if (LOCATION_LOCUS (e2->goto_locus) != UNKNOWN_LOCATION |
78bde837 | 3928 | && !(e2->flags & (EDGE_ABNORMAL | EDGE_FALLTHRU)) |
5368224f | 3929 | && e->goto_locus == e2->goto_locus) |
78bde837 SB |
3930 | redirect_edge_and_branch (e2, nb); |
3931 | else | |
3932 | ei_next (&ei2); | |
3933 | } | |
3934 | } | |
3935 | } | |
3936 | \f | |
3937 | /* Perform sanity checks on the insn chain. | |
3938 | 1. Check that next/prev pointers are consistent in both the forward and | |
3939 | reverse direction. | |
3940 | 2. Count insns in chain, going both directions, and check if equal. | |
3941 | 3. Check that get_last_insn () returns the actual end of chain. */ | |
3942 | ||
3943 | DEBUG_FUNCTION void | |
3944 | verify_insn_chain (void) | |
3945 | { | |
3946 | rtx x, prevx, nextx; | |
3947 | int insn_cnt1, insn_cnt2; | |
3948 | ||
3949 | for (prevx = NULL, insn_cnt1 = 1, x = get_insns (); | |
3950 | x != 0; | |
3951 | prevx = x, insn_cnt1++, x = NEXT_INSN (x)) | |
3952 | gcc_assert (PREV_INSN (x) == prevx); | |
3953 | ||
3954 | gcc_assert (prevx == get_last_insn ()); | |
3955 | ||
3956 | for (nextx = NULL, insn_cnt2 = 1, x = get_last_insn (); | |
3957 | x != 0; | |
3958 | nextx = x, insn_cnt2++, x = PREV_INSN (x)) | |
3959 | gcc_assert (NEXT_INSN (x) == nextx); | |
3960 | ||
3961 | gcc_assert (insn_cnt1 == insn_cnt2); | |
3962 | } | |
3963 | \f | |
3964 | /* If we have assembler epilogues, the block falling through to exit must | |
3965 | be the last one in the reordered chain when we reach final. Ensure | |
3966 | that this condition is met. */ | |
3967 | static void | |
3968 | fixup_fallthru_exit_predecessor (void) | |
3969 | { | |
3970 | edge e; | |
3971 | basic_block bb = NULL; | |
3972 | ||
3973 | /* This transformation is not valid before reload, because we might | |
3974 | separate a call from the instruction that copies the return | |
3975 | value. */ | |
3976 | gcc_assert (reload_completed); | |
3977 | ||
fefa31b5 | 3978 | e = find_fallthru_edge (EXIT_BLOCK_PTR_FOR_FN (cfun)->preds); |
78bde837 SB |
3979 | if (e) |
3980 | bb = e->src; | |
3981 | ||
3982 | if (bb && bb->aux) | |
3983 | { | |
fefa31b5 | 3984 | basic_block c = ENTRY_BLOCK_PTR_FOR_FN (cfun)->next_bb; |
78bde837 SB |
3985 | |
3986 | /* If the very first block is the one with the fall-through exit | |
3987 | edge, we have to split that block. */ | |
3988 | if (c == bb) | |
3989 | { | |
3990 | bb = split_block (bb, NULL)->dest; | |
3991 | bb->aux = c->aux; | |
3992 | c->aux = bb; | |
3993 | BB_FOOTER (bb) = BB_FOOTER (c); | |
3994 | BB_FOOTER (c) = NULL; | |
3995 | } | |
3996 | ||
3997 | while (c->aux != bb) | |
3998 | c = (basic_block) c->aux; | |
3999 | ||
4000 | c->aux = bb->aux; | |
4001 | while (c->aux) | |
4002 | c = (basic_block) c->aux; | |
4003 | ||
4004 | c->aux = bb; | |
4005 | bb->aux = NULL; | |
4006 | } | |
4007 | } | |
4008 | ||
4009 | /* In case there are more than one fallthru predecessors of exit, force that | |
4010 | there is only one. */ | |
4011 | ||
4012 | static void | |
4013 | force_one_exit_fallthru (void) | |
4014 | { | |
4015 | edge e, predecessor = NULL; | |
4016 | bool more = false; | |
4017 | edge_iterator ei; | |
4018 | basic_block forwarder, bb; | |
4019 | ||
fefa31b5 | 4020 | FOR_EACH_EDGE (e, ei, EXIT_BLOCK_PTR_FOR_FN (cfun)->preds) |
78bde837 SB |
4021 | if (e->flags & EDGE_FALLTHRU) |
4022 | { | |
4023 | if (predecessor == NULL) | |
4024 | predecessor = e; | |
4025 | else | |
4026 | { | |
4027 | more = true; | |
4028 | break; | |
4029 | } | |
4030 | } | |
4031 | ||
4032 | if (!more) | |
4033 | return; | |
4034 | ||
4035 | /* Exit has several fallthru predecessors. Create a forwarder block for | |
4036 | them. */ | |
4037 | forwarder = split_edge (predecessor); | |
fefa31b5 DM |
4038 | for (ei = ei_start (EXIT_BLOCK_PTR_FOR_FN (cfun)->preds); |
4039 | (e = ei_safe_edge (ei)); ) | |
78bde837 SB |
4040 | { |
4041 | if (e->src == forwarder | |
4042 | || !(e->flags & EDGE_FALLTHRU)) | |
4043 | ei_next (&ei); | |
4044 | else | |
4045 | redirect_edge_and_branch_force (e, forwarder); | |
4046 | } | |
4047 | ||
4048 | /* Fix up the chain of blocks -- make FORWARDER immediately precede the | |
4049 | exit block. */ | |
11cd3bed | 4050 | FOR_EACH_BB_FN (bb, cfun) |
78bde837 SB |
4051 | { |
4052 | if (bb->aux == NULL && bb != forwarder) | |
4053 | { | |
4054 | bb->aux = forwarder; | |
4055 | break; | |
4056 | } | |
4057 | } | |
4058 | } | |
4059 | \f | |
4060 | /* Return true in case it is possible to duplicate the basic block BB. */ | |
4061 | ||
4062 | static bool | |
4063 | cfg_layout_can_duplicate_bb_p (const_basic_block bb) | |
4064 | { | |
4065 | /* Do not attempt to duplicate tablejumps, as we need to unshare | |
4066 | the dispatch table. This is difficult to do, as the instructions | |
4067 | computing jump destination may be hoisted outside the basic block. */ | |
4068 | if (tablejump_p (BB_END (bb), NULL, NULL)) | |
4069 | return false; | |
4070 | ||
4071 | /* Do not duplicate blocks containing insns that can't be copied. */ | |
4072 | if (targetm.cannot_copy_insn_p) | |
4073 | { | |
4074 | rtx insn = BB_HEAD (bb); | |
4075 | while (1) | |
4076 | { | |
4077 | if (INSN_P (insn) && targetm.cannot_copy_insn_p (insn)) | |
4078 | return false; | |
4079 | if (insn == BB_END (bb)) | |
4080 | break; | |
4081 | insn = NEXT_INSN (insn); | |
4082 | } | |
4083 | } | |
4084 | ||
4085 | return true; | |
4086 | } | |
4087 | ||
4088 | rtx | |
4089 | duplicate_insn_chain (rtx from, rtx to) | |
4090 | { | |
39718607 | 4091 | rtx insn, next, last, copy; |
78bde837 SB |
4092 | |
4093 | /* Avoid updating of boundaries of previous basic block. The | |
4094 | note will get removed from insn stream in fixup. */ | |
4095 | last = emit_note (NOTE_INSN_DELETED); | |
4096 | ||
4097 | /* Create copy at the end of INSN chain. The chain will | |
4098 | be reordered later. */ | |
4099 | for (insn = from; insn != NEXT_INSN (to); insn = NEXT_INSN (insn)) | |
4100 | { | |
4101 | switch (GET_CODE (insn)) | |
4102 | { | |
4103 | case DEBUG_INSN: | |
4104 | /* Don't duplicate label debug insns. */ | |
4105 | if (TREE_CODE (INSN_VAR_LOCATION_DECL (insn)) == LABEL_DECL) | |
4106 | break; | |
4107 | /* FALLTHRU */ | |
4108 | case INSN: | |
4109 | case CALL_INSN: | |
4110 | case JUMP_INSN: | |
78bde837 SB |
4111 | copy = emit_copy_of_insn_after (insn, get_last_insn ()); |
4112 | if (JUMP_P (insn) && JUMP_LABEL (insn) != NULL_RTX | |
4113 | && ANY_RETURN_P (JUMP_LABEL (insn))) | |
4114 | JUMP_LABEL (copy) = JUMP_LABEL (insn); | |
4115 | maybe_copy_prologue_epilogue_insn (insn, copy); | |
4116 | break; | |
4117 | ||
39718607 SB |
4118 | case JUMP_TABLE_DATA: |
4119 | /* Avoid copying of dispatch tables. We never duplicate | |
4120 | tablejumps, so this can hit only in case the table got | |
4121 | moved far from original jump. | |
4122 | Avoid copying following barrier as well if any | |
4123 | (and debug insns in between). */ | |
4124 | for (next = NEXT_INSN (insn); | |
4125 | next != NEXT_INSN (to); | |
4126 | next = NEXT_INSN (next)) | |
4127 | if (!DEBUG_INSN_P (next)) | |
4128 | break; | |
4129 | if (next != NEXT_INSN (to) && BARRIER_P (next)) | |
4130 | insn = next; | |
4131 | break; | |
4132 | ||
78bde837 SB |
4133 | case CODE_LABEL: |
4134 | break; | |
4135 | ||
4136 | case BARRIER: | |
4137 | emit_barrier (); | |
4138 | break; | |
4139 | ||
4140 | case NOTE: | |
4141 | switch (NOTE_KIND (insn)) | |
4142 | { | |
4143 | /* In case prologue is empty and function contain label | |
4144 | in first BB, we may want to copy the block. */ | |
4145 | case NOTE_INSN_PROLOGUE_END: | |
4146 | ||
4147 | case NOTE_INSN_DELETED: | |
4148 | case NOTE_INSN_DELETED_LABEL: | |
4149 | case NOTE_INSN_DELETED_DEBUG_LABEL: | |
4150 | /* No problem to strip these. */ | |
4151 | case NOTE_INSN_FUNCTION_BEG: | |
4152 | /* There is always just single entry to function. */ | |
4153 | case NOTE_INSN_BASIC_BLOCK: | |
3371a64f TJ |
4154 | /* We should only switch text sections once. */ |
4155 | case NOTE_INSN_SWITCH_TEXT_SECTIONS: | |
78bde837 SB |
4156 | break; |
4157 | ||
4158 | case NOTE_INSN_EPILOGUE_BEG: | |
78bde837 SB |
4159 | emit_note_copy (insn); |
4160 | break; | |
4161 | ||
4162 | default: | |
4163 | /* All other notes should have already been eliminated. */ | |
4164 | gcc_unreachable (); | |
4165 | } | |
4166 | break; | |
4167 | default: | |
4168 | gcc_unreachable (); | |
4169 | } | |
4170 | } | |
4171 | insn = NEXT_INSN (last); | |
4172 | delete_insn (last); | |
4173 | return insn; | |
4174 | } | |
4175 | ||
4176 | /* Create a duplicate of the basic block BB. */ | |
4177 | ||
4178 | static basic_block | |
4179 | cfg_layout_duplicate_bb (basic_block bb) | |
4180 | { | |
4181 | rtx insn; | |
4182 | basic_block new_bb; | |
4183 | ||
4184 | insn = duplicate_insn_chain (BB_HEAD (bb), BB_END (bb)); | |
4185 | new_bb = create_basic_block (insn, | |
4186 | insn ? get_last_insn () : NULL, | |
fefa31b5 | 4187 | EXIT_BLOCK_PTR_FOR_FN (cfun)->prev_bb); |
78bde837 SB |
4188 | |
4189 | BB_COPY_PARTITION (new_bb, bb); | |
4190 | if (BB_HEADER (bb)) | |
4191 | { | |
4192 | insn = BB_HEADER (bb); | |
4193 | while (NEXT_INSN (insn)) | |
4194 | insn = NEXT_INSN (insn); | |
4195 | insn = duplicate_insn_chain (BB_HEADER (bb), insn); | |
4196 | if (insn) | |
4197 | BB_HEADER (new_bb) = unlink_insn_chain (insn, get_last_insn ()); | |
4198 | } | |
4199 | ||
4200 | if (BB_FOOTER (bb)) | |
4201 | { | |
4202 | insn = BB_FOOTER (bb); | |
4203 | while (NEXT_INSN (insn)) | |
4204 | insn = NEXT_INSN (insn); | |
4205 | insn = duplicate_insn_chain (BB_FOOTER (bb), insn); | |
4206 | if (insn) | |
4207 | BB_FOOTER (new_bb) = unlink_insn_chain (insn, get_last_insn ()); | |
4208 | } | |
4209 | ||
4210 | return new_bb; | |
4211 | } | |
4212 | ||
4213 | \f | |
4214 | /* Main entry point to this module - initialize the datastructures for | |
4215 | CFG layout changes. It keeps LOOPS up-to-date if not null. | |
4216 | ||
4217 | FLAGS is a set of additional flags to pass to cleanup_cfg(). */ | |
4218 | ||
4219 | void | |
4220 | cfg_layout_initialize (unsigned int flags) | |
4221 | { | |
4222 | rtx x; | |
4223 | basic_block bb; | |
4224 | ||
4ca19309 TJ |
4225 | /* Once bb reordering is complete, cfg layout mode should not be re-entered. |
4226 | Entering cfg layout mode will perform optimizations on the cfg that | |
4227 | could affect the bb layout negatively or even require fixups. An | |
4228 | example of the latter is if edge forwarding performed when optimizing | |
4229 | the cfg layout required moving a block from the hot to the cold section | |
4230 | under -freorder-blocks-and-partition. This would create an illegal | |
4231 | partitioning unless some manual fixup was performed. */ | |
4232 | gcc_assert (!crtl->bb_reorder_complete); | |
4233 | ||
78bde837 SB |
4234 | initialize_original_copy_tables (); |
4235 | ||
4236 | cfg_layout_rtl_register_cfg_hooks (); | |
4237 | ||
4238 | record_effective_endpoints (); | |
4239 | ||
4240 | /* Make sure that the targets of non local gotos are marked. */ | |
4241 | for (x = nonlocal_goto_handler_labels; x; x = XEXP (x, 1)) | |
4242 | { | |
4243 | bb = BLOCK_FOR_INSN (XEXP (x, 0)); | |
4244 | bb->flags |= BB_NON_LOCAL_GOTO_TARGET; | |
4245 | } | |
4246 | ||
4247 | cleanup_cfg (CLEANUP_CFGLAYOUT | flags); | |
4248 | } | |
4249 | ||
4250 | /* Splits superblocks. */ | |
4251 | void | |
4252 | break_superblocks (void) | |
4253 | { | |
4254 | sbitmap superblocks; | |
4255 | bool need = false; | |
4256 | basic_block bb; | |
4257 | ||
8b1c6fd7 | 4258 | superblocks = sbitmap_alloc (last_basic_block_for_fn (cfun)); |
f61e445a | 4259 | bitmap_clear (superblocks); |
78bde837 | 4260 | |
11cd3bed | 4261 | FOR_EACH_BB_FN (bb, cfun) |
78bde837 SB |
4262 | if (bb->flags & BB_SUPERBLOCK) |
4263 | { | |
4264 | bb->flags &= ~BB_SUPERBLOCK; | |
d7c028c0 | 4265 | bitmap_set_bit (superblocks, bb->index); |
78bde837 SB |
4266 | need = true; |
4267 | } | |
4268 | ||
4269 | if (need) | |
4270 | { | |
4271 | rebuild_jump_labels (get_insns ()); | |
4272 | find_many_sub_basic_blocks (superblocks); | |
4273 | } | |
4274 | ||
4275 | free (superblocks); | |
4276 | } | |
4277 | ||
4278 | /* Finalize the changes: reorder insn list according to the sequence specified | |
29f3fd5b | 4279 | by aux pointers, enter compensation code, rebuild scope forest. */ |
78bde837 SB |
4280 | |
4281 | void | |
4282 | cfg_layout_finalize (void) | |
4283 | { | |
4284 | #ifdef ENABLE_CHECKING | |
4285 | verify_flow_info (); | |
4286 | #endif | |
4287 | force_one_exit_fallthru (); | |
4288 | rtl_register_cfg_hooks (); | |
4289 | if (reload_completed | |
4290 | #ifdef HAVE_epilogue | |
4291 | && !HAVE_epilogue | |
4292 | #endif | |
4293 | ) | |
4294 | fixup_fallthru_exit_predecessor (); | |
4295 | fixup_reorder_chain (); | |
4296 | ||
29f3fd5b SB |
4297 | rebuild_jump_labels (get_insns ()); |
4298 | delete_dead_jumptables (); | |
4299 | ||
78bde837 SB |
4300 | #ifdef ENABLE_CHECKING |
4301 | verify_insn_chain (); | |
4302 | verify_flow_info (); | |
4303 | #endif | |
4304 | } | |
4305 | ||
ba5e9aca | 4306 | |
9ee634e3 | 4307 | /* Same as split_block but update cfg_layout structures. */ |
f470c378 ZD |
4308 | |
4309 | static basic_block | |
d329e058 | 4310 | cfg_layout_split_block (basic_block bb, void *insnp) |
9ee634e3 | 4311 | { |
ae50c0cb | 4312 | rtx insn = (rtx) insnp; |
f470c378 | 4313 | basic_block new_bb = rtl_split_block (bb, insn); |
9ee634e3 | 4314 | |
bcc708fc MM |
4315 | BB_FOOTER (new_bb) = BB_FOOTER (bb); |
4316 | BB_FOOTER (bb) = NULL; | |
9ee634e3 | 4317 | |
f470c378 | 4318 | return new_bb; |
9ee634e3 JH |
4319 | } |
4320 | ||
9ee634e3 | 4321 | /* Redirect Edge to DEST. */ |
6de9cd9a | 4322 | static edge |
d329e058 | 4323 | cfg_layout_redirect_edge_and_branch (edge e, basic_block dest) |
9ee634e3 JH |
4324 | { |
4325 | basic_block src = e->src; | |
6de9cd9a | 4326 | edge ret; |
9ee634e3 | 4327 | |
bc35512f | 4328 | if (e->flags & (EDGE_ABNORMAL_CALL | EDGE_EH)) |
6de9cd9a | 4329 | return NULL; |
bc35512f | 4330 | |
3348b696 | 4331 | if (e->dest == dest) |
6de9cd9a | 4332 | return e; |
bc35512f | 4333 | |
fefa31b5 | 4334 | if (e->src != ENTRY_BLOCK_PTR_FOR_FN (cfun) |
6de9cd9a | 4335 | && (ret = try_redirect_by_replacing_jump (e, dest, true))) |
f345f21a | 4336 | { |
6fb5fa3c | 4337 | df_set_bb_dirty (src); |
6de9cd9a | 4338 | return ret; |
f345f21a | 4339 | } |
bc35512f | 4340 | |
fefa31b5 | 4341 | if (e->src == ENTRY_BLOCK_PTR_FOR_FN (cfun) |
bc35512f JH |
4342 | && (e->flags & EDGE_FALLTHRU) && !(e->flags & EDGE_COMPLEX)) |
4343 | { | |
c263766c RH |
4344 | if (dump_file) |
4345 | fprintf (dump_file, "Redirecting entry edge from bb %i to %i\n", | |
bc35512f JH |
4346 | e->src->index, dest->index); |
4347 | ||
6fb5fa3c | 4348 | df_set_bb_dirty (e->src); |
bc35512f | 4349 | redirect_edge_succ (e, dest); |
6de9cd9a | 4350 | return e; |
bc35512f JH |
4351 | } |
4352 | ||
9ee634e3 JH |
4353 | /* Redirect_edge_and_branch may decide to turn branch into fallthru edge |
4354 | in the case the basic block appears to be in sequence. Avoid this | |
4355 | transformation. */ | |
4356 | ||
9ee634e3 JH |
4357 | if (e->flags & EDGE_FALLTHRU) |
4358 | { | |
4359 | /* Redirect any branch edges unified with the fallthru one. */ | |
4b4bf941 | 4360 | if (JUMP_P (BB_END (src)) |
432f982f JH |
4361 | && label_is_jump_target_p (BB_HEAD (e->dest), |
4362 | BB_END (src))) | |
9ee634e3 | 4363 | { |
341c100f | 4364 | edge redirected; |
c22cacf3 | 4365 | |
c263766c RH |
4366 | if (dump_file) |
4367 | fprintf (dump_file, "Fallthru edge unified with branch " | |
432f982f JH |
4368 | "%i->%i redirected to %i\n", |
4369 | e->src->index, e->dest->index, dest->index); | |
4370 | e->flags &= ~EDGE_FALLTHRU; | |
341c100f NS |
4371 | redirected = redirect_branch_edge (e, dest); |
4372 | gcc_assert (redirected); | |
0c617be4 JL |
4373 | redirected->flags |= EDGE_FALLTHRU; |
4374 | df_set_bb_dirty (redirected->src); | |
4375 | return redirected; | |
9ee634e3 JH |
4376 | } |
4377 | /* In case we are redirecting fallthru edge to the branch edge | |
c22cacf3 | 4378 | of conditional jump, remove it. */ |
628f6a4e | 4379 | if (EDGE_COUNT (src->succs) == 2) |
9ee634e3 | 4380 | { |
03101c6f KH |
4381 | /* Find the edge that is different from E. */ |
4382 | edge s = EDGE_SUCC (src, EDGE_SUCC (src, 0) == e); | |
628f6a4e | 4383 | |
9ee634e3 | 4384 | if (s->dest == dest |
a813c111 SB |
4385 | && any_condjump_p (BB_END (src)) |
4386 | && onlyjump_p (BB_END (src))) | |
4387 | delete_insn (BB_END (src)); | |
9ee634e3 | 4388 | } |
c263766c | 4389 | if (dump_file) |
dc764d10 | 4390 | fprintf (dump_file, "Redirecting fallthru edge %i->%i to %i\n", |
bc35512f | 4391 | e->src->index, e->dest->index, dest->index); |
0c617be4 | 4392 | ret = redirect_edge_succ_nodup (e, dest); |
9ee634e3 JH |
4393 | } |
4394 | else | |
bc35512f | 4395 | ret = redirect_branch_edge (e, dest); |
9ee634e3 JH |
4396 | |
4397 | /* We don't want simplejumps in the insn stream during cfglayout. */ | |
341c100f | 4398 | gcc_assert (!simplejump_p (BB_END (src))); |
9ee634e3 | 4399 | |
6fb5fa3c | 4400 | df_set_bb_dirty (src); |
9ee634e3 JH |
4401 | return ret; |
4402 | } | |
4403 | ||
4404 | /* Simple wrapper as we always can redirect fallthru edges. */ | |
4405 | static basic_block | |
d329e058 | 4406 | cfg_layout_redirect_edge_and_branch_force (edge e, basic_block dest) |
9ee634e3 | 4407 | { |
341c100f NS |
4408 | edge redirected = cfg_layout_redirect_edge_and_branch (e, dest); |
4409 | ||
4410 | gcc_assert (redirected); | |
9ee634e3 JH |
4411 | return NULL; |
4412 | } | |
4413 | ||
f470c378 ZD |
4414 | /* Same as delete_basic_block but update cfg_layout structures. */ |
4415 | ||
9ee634e3 | 4416 | static void |
d329e058 | 4417 | cfg_layout_delete_block (basic_block bb) |
9ee634e3 | 4418 | { |
a813c111 | 4419 | rtx insn, next, prev = PREV_INSN (BB_HEAD (bb)), *to, remaints; |
9ee634e3 | 4420 | |
bcc708fc | 4421 | if (BB_HEADER (bb)) |
9ee634e3 | 4422 | { |
a813c111 | 4423 | next = BB_HEAD (bb); |
9ee634e3 | 4424 | if (prev) |
bcc708fc | 4425 | NEXT_INSN (prev) = BB_HEADER (bb); |
9ee634e3 | 4426 | else |
bcc708fc MM |
4427 | set_first_insn (BB_HEADER (bb)); |
4428 | PREV_INSN (BB_HEADER (bb)) = prev; | |
4429 | insn = BB_HEADER (bb); | |
9ee634e3 JH |
4430 | while (NEXT_INSN (insn)) |
4431 | insn = NEXT_INSN (insn); | |
4432 | NEXT_INSN (insn) = next; | |
4433 | PREV_INSN (next) = insn; | |
4434 | } | |
a813c111 | 4435 | next = NEXT_INSN (BB_END (bb)); |
bcc708fc | 4436 | if (BB_FOOTER (bb)) |
9ee634e3 | 4437 | { |
bcc708fc | 4438 | insn = BB_FOOTER (bb); |
bc35512f JH |
4439 | while (insn) |
4440 | { | |
4b4bf941 | 4441 | if (BARRIER_P (insn)) |
bc35512f JH |
4442 | { |
4443 | if (PREV_INSN (insn)) | |
4444 | NEXT_INSN (PREV_INSN (insn)) = NEXT_INSN (insn); | |
4445 | else | |
bcc708fc | 4446 | BB_FOOTER (bb) = NEXT_INSN (insn); |
bc35512f JH |
4447 | if (NEXT_INSN (insn)) |
4448 | PREV_INSN (NEXT_INSN (insn)) = PREV_INSN (insn); | |
4449 | } | |
4b4bf941 | 4450 | if (LABEL_P (insn)) |
bc35512f JH |
4451 | break; |
4452 | insn = NEXT_INSN (insn); | |
4453 | } | |
bcc708fc | 4454 | if (BB_FOOTER (bb)) |
bc35512f | 4455 | { |
a813c111 | 4456 | insn = BB_END (bb); |
bcc708fc MM |
4457 | NEXT_INSN (insn) = BB_FOOTER (bb); |
4458 | PREV_INSN (BB_FOOTER (bb)) = insn; | |
bc35512f JH |
4459 | while (NEXT_INSN (insn)) |
4460 | insn = NEXT_INSN (insn); | |
4461 | NEXT_INSN (insn) = next; | |
4462 | if (next) | |
4463 | PREV_INSN (next) = insn; | |
4464 | else | |
4465 | set_last_insn (insn); | |
4466 | } | |
9ee634e3 | 4467 | } |
fefa31b5 | 4468 | if (bb->next_bb != EXIT_BLOCK_PTR_FOR_FN (cfun)) |
bcc708fc | 4469 | to = &BB_HEADER (bb->next_bb); |
9ee634e3 JH |
4470 | else |
4471 | to = &cfg_layout_function_footer; | |
997de8ed | 4472 | |
9ee634e3 JH |
4473 | rtl_delete_block (bb); |
4474 | ||
4475 | if (prev) | |
4476 | prev = NEXT_INSN (prev); | |
d329e058 | 4477 | else |
9ee634e3 JH |
4478 | prev = get_insns (); |
4479 | if (next) | |
4480 | next = PREV_INSN (next); | |
d329e058 | 4481 | else |
9ee634e3 JH |
4482 | next = get_last_insn (); |
4483 | ||
4484 | if (next && NEXT_INSN (next) != prev) | |
4485 | { | |
4486 | remaints = unlink_insn_chain (prev, next); | |
4487 | insn = remaints; | |
4488 | while (NEXT_INSN (insn)) | |
4489 | insn = NEXT_INSN (insn); | |
4490 | NEXT_INSN (insn) = *to; | |
4491 | if (*to) | |
4492 | PREV_INSN (*to) = insn; | |
4493 | *to = remaints; | |
4494 | } | |
4495 | } | |
4496 | ||
beb235f8 | 4497 | /* Return true when blocks A and B can be safely merged. */ |
b48d0358 | 4498 | |
bc35512f | 4499 | static bool |
b48d0358 | 4500 | cfg_layout_can_merge_blocks_p (basic_block a, basic_block b) |
bc35512f | 4501 | { |
750054a2 CT |
4502 | /* If we are partitioning hot/cold basic blocks, we don't want to |
4503 | mess up unconditional or indirect jumps that cross between hot | |
076c7ab8 ZW |
4504 | and cold sections. |
4505 | ||
8e8d5162 | 4506 | Basic block partitioning may result in some jumps that appear to |
c22cacf3 MS |
4507 | be optimizable (or blocks that appear to be mergeable), but which really |
4508 | must be left untouched (they are required to make it safely across | |
4509 | partition boundaries). See the comments at the top of | |
8e8d5162 CT |
4510 | bb-reorder.c:partition_hot_cold_basic_blocks for complete details. */ |
4511 | ||
87c8b4be | 4512 | if (BB_PARTITION (a) != BB_PARTITION (b)) |
076c7ab8 | 4513 | return false; |
750054a2 | 4514 | |
7d776ee2 RG |
4515 | /* Protect the loop latches. */ |
4516 | if (current_loops && b->loop_father->latch == b) | |
4517 | return false; | |
4518 | ||
894a84b5 BS |
4519 | /* If we would end up moving B's instructions, make sure it doesn't fall |
4520 | through into the exit block, since we cannot recover from a fallthrough | |
4521 | edge into the exit block occurring in the middle of a function. */ | |
4522 | if (NEXT_INSN (BB_END (a)) != BB_HEAD (b)) | |
4523 | { | |
4524 | edge e = find_fallthru_edge (b->succs); | |
fefa31b5 | 4525 | if (e && e->dest == EXIT_BLOCK_PTR_FOR_FN (cfun)) |
894a84b5 BS |
4526 | return false; |
4527 | } | |
4528 | ||
bc35512f | 4529 | /* There must be exactly one edge in between the blocks. */ |
c5cbcccf ZD |
4530 | return (single_succ_p (a) |
4531 | && single_succ (a) == b | |
4532 | && single_pred_p (b) == 1 | |
628f6a4e | 4533 | && a != b |
bc35512f | 4534 | /* Must be simple edge. */ |
c5cbcccf | 4535 | && !(single_succ_edge (a)->flags & EDGE_COMPLEX) |
fefa31b5 DM |
4536 | && a != ENTRY_BLOCK_PTR_FOR_FN (cfun) |
4537 | && b != EXIT_BLOCK_PTR_FOR_FN (cfun) | |
49ea3702 SB |
4538 | /* If the jump insn has side effects, we can't kill the edge. |
4539 | When not optimizing, try_redirect_by_replacing_jump will | |
4540 | not allow us to redirect an edge by replacing a table jump. */ | |
4b4bf941 | 4541 | && (!JUMP_P (BB_END (a)) |
49ea3702 | 4542 | || ((!optimize || reload_completed) |
a813c111 | 4543 | ? simplejump_p (BB_END (a)) : onlyjump_p (BB_END (a))))); |
bc35512f JH |
4544 | } |
4545 | ||
41806d92 NS |
4546 | /* Merge block A and B. The blocks must be mergeable. */ |
4547 | ||
bc35512f JH |
4548 | static void |
4549 | cfg_layout_merge_blocks (basic_block a, basic_block b) | |
4550 | { | |
50a36e42 | 4551 | bool forwarder_p = (b->flags & BB_FORWARDER_BLOCK) != 0; |
f9df6f16 | 4552 | rtx insn; |
50a36e42 | 4553 | |
77a74ed7 | 4554 | gcc_checking_assert (cfg_layout_can_merge_blocks_p (a, b)); |
bc35512f | 4555 | |
6fb5fa3c | 4556 | if (dump_file) |
50a36e42 EB |
4557 | fprintf (dump_file, "Merging block %d into block %d...\n", b->index, |
4558 | a->index); | |
6fb5fa3c | 4559 | |
bc35512f | 4560 | /* If there was a CODE_LABEL beginning B, delete it. */ |
4b4bf941 | 4561 | if (LABEL_P (BB_HEAD (b))) |
2c97f8e4 | 4562 | { |
2c97f8e4 RH |
4563 | delete_insn (BB_HEAD (b)); |
4564 | } | |
bc35512f JH |
4565 | |
4566 | /* We should have fallthru edge in a, or we can do dummy redirection to get | |
4567 | it cleaned up. */ | |
4b4bf941 | 4568 | if (JUMP_P (BB_END (a))) |
628f6a4e | 4569 | try_redirect_by_replacing_jump (EDGE_SUCC (a, 0), b, true); |
341c100f | 4570 | gcc_assert (!JUMP_P (BB_END (a))); |
bc35512f | 4571 | |
9be94227 | 4572 | /* When not optimizing CFG and the edge is the only place in RTL which holds |
7241571e | 4573 | some unique locus, emit a nop with that locus in between. */ |
9be94227 EB |
4574 | if (!optimize) |
4575 | emit_nop_for_unique_locus_between (a, b); | |
7241571e | 4576 | |
4c8af858 SB |
4577 | /* Move things from b->footer after a->footer. */ |
4578 | if (BB_FOOTER (b)) | |
bc35512f | 4579 | { |
4c8af858 SB |
4580 | if (!BB_FOOTER (a)) |
4581 | BB_FOOTER (a) = BB_FOOTER (b); | |
4582 | else | |
4583 | { | |
4584 | rtx last = BB_FOOTER (a); | |
4585 | ||
4586 | while (NEXT_INSN (last)) | |
4587 | last = NEXT_INSN (last); | |
4588 | NEXT_INSN (last) = BB_FOOTER (b); | |
4589 | PREV_INSN (BB_FOOTER (b)) = last; | |
4590 | } | |
4591 | BB_FOOTER (b) = NULL; | |
4592 | } | |
4593 | ||
4594 | /* Move things from b->header before a->footer. | |
4595 | Note that this may include dead tablejump data, but we don't clean | |
4596 | those up until we go out of cfglayout mode. */ | |
4597 | if (BB_HEADER (b)) | |
4598 | { | |
4599 | if (! BB_FOOTER (a)) | |
4600 | BB_FOOTER (a) = BB_HEADER (b); | |
4601 | else | |
4602 | { | |
4603 | rtx last = BB_HEADER (b); | |
4604 | ||
4605 | while (NEXT_INSN (last)) | |
4606 | last = NEXT_INSN (last); | |
4607 | NEXT_INSN (last) = BB_FOOTER (a); | |
4608 | PREV_INSN (BB_FOOTER (a)) = last; | |
4609 | BB_FOOTER (a) = BB_HEADER (b); | |
4610 | } | |
bcc708fc | 4611 | BB_HEADER (b) = NULL; |
bc35512f JH |
4612 | } |
4613 | ||
4614 | /* In the case basic blocks are not adjacent, move them around. */ | |
a813c111 | 4615 | if (NEXT_INSN (BB_END (a)) != BB_HEAD (b)) |
bc35512f | 4616 | { |
f9df6f16 | 4617 | insn = unlink_insn_chain (BB_HEAD (b), BB_END (b)); |
6c3d0e31 | 4618 | |
f9df6f16 | 4619 | emit_insn_after_noloc (insn, BB_END (a), a); |
bc35512f JH |
4620 | } |
4621 | /* Otherwise just re-associate the instructions. */ | |
4622 | else | |
4623 | { | |
a813c111 | 4624 | insn = BB_HEAD (b); |
a813c111 | 4625 | BB_END (a) = BB_END (b); |
bc35512f JH |
4626 | } |
4627 | ||
f9df6f16 JJ |
4628 | /* emit_insn_after_noloc doesn't call df_insn_change_bb. |
4629 | We need to explicitly call. */ | |
4630 | update_bb_for_insn_chain (insn, BB_END (b), a); | |
4631 | ||
4632 | /* Skip possible DELETED_LABEL insn. */ | |
4633 | if (!NOTE_INSN_BASIC_BLOCK_P (insn)) | |
4634 | insn = NEXT_INSN (insn); | |
4635 | gcc_assert (NOTE_INSN_BASIC_BLOCK_P (insn)); | |
4c8af858 | 4636 | BB_HEAD (b) = BB_END (b) = NULL; |
f9df6f16 JJ |
4637 | delete_insn (insn); |
4638 | ||
6fb5fa3c DB |
4639 | df_bb_delete (b->index); |
4640 | ||
50a36e42 | 4641 | /* If B was a forwarder block, propagate the locus on the edge. */ |
2f13f2de | 4642 | if (forwarder_p |
fbc68f2a | 4643 | && LOCATION_LOCUS (EDGE_SUCC (b, 0)->goto_locus) == UNKNOWN_LOCATION) |
50a36e42 EB |
4644 | EDGE_SUCC (b, 0)->goto_locus = EDGE_SUCC (a, 0)->goto_locus; |
4645 | ||
c263766c | 4646 | if (dump_file) |
50a36e42 | 4647 | fprintf (dump_file, "Merged blocks %d and %d.\n", a->index, b->index); |
bc35512f JH |
4648 | } |
4649 | ||
4650 | /* Split edge E. */ | |
f470c378 | 4651 | |
bc35512f JH |
4652 | static basic_block |
4653 | cfg_layout_split_edge (edge e) | |
4654 | { | |
bc35512f | 4655 | basic_block new_bb = |
fefa31b5 | 4656 | create_basic_block (e->src != ENTRY_BLOCK_PTR_FOR_FN (cfun) |
a813c111 | 4657 | ? NEXT_INSN (BB_END (e->src)) : get_insns (), |
bc35512f JH |
4658 | NULL_RTX, e->src); |
4659 | ||
fefa31b5 | 4660 | if (e->dest == EXIT_BLOCK_PTR_FOR_FN (cfun)) |
3e7eb734 JJ |
4661 | BB_COPY_PARTITION (new_bb, e->src); |
4662 | else | |
4663 | BB_COPY_PARTITION (new_bb, e->dest); | |
a9b2ee88 | 4664 | make_edge (new_bb, e->dest, EDGE_FALLTHRU); |
bc35512f JH |
4665 | redirect_edge_and_branch_force (e, new_bb); |
4666 | ||
4667 | return new_bb; | |
4668 | } | |
4669 | ||
f470c378 ZD |
4670 | /* Do postprocessing after making a forwarder block joined by edge FALLTHRU. */ |
4671 | ||
4672 | static void | |
4673 | rtl_make_forwarder_block (edge fallthru ATTRIBUTE_UNUSED) | |
4674 | { | |
4675 | } | |
4676 | ||
df92c640 SB |
4677 | /* Return true if BB contains only labels or non-executable |
4678 | instructions. */ | |
4679 | ||
4680 | static bool | |
4681 | rtl_block_empty_p (basic_block bb) | |
4682 | { | |
4683 | rtx insn; | |
4684 | ||
fefa31b5 DM |
4685 | if (bb == ENTRY_BLOCK_PTR_FOR_FN (cfun) |
4686 | || bb == EXIT_BLOCK_PTR_FOR_FN (cfun)) | |
df92c640 SB |
4687 | return true; |
4688 | ||
4689 | FOR_BB_INSNS (bb, insn) | |
4690 | if (NONDEBUG_INSN_P (insn) && !any_uncondjump_p (insn)) | |
4691 | return false; | |
4692 | ||
4693 | return true; | |
4694 | } | |
4695 | ||
4696 | /* Split a basic block if it ends with a conditional branch and if | |
4697 | the other part of the block is not empty. */ | |
4698 | ||
4699 | static basic_block | |
4700 | rtl_split_block_before_cond_jump (basic_block bb) | |
4701 | { | |
4702 | rtx insn; | |
4703 | rtx split_point = NULL; | |
4704 | rtx last = NULL; | |
4705 | bool found_code = false; | |
4706 | ||
4707 | FOR_BB_INSNS (bb, insn) | |
4708 | { | |
4709 | if (any_condjump_p (insn)) | |
4710 | split_point = last; | |
4711 | else if (NONDEBUG_INSN_P (insn)) | |
4712 | found_code = true; | |
4713 | last = insn; | |
4714 | } | |
4715 | ||
4716 | /* Did not find everything. */ | |
4717 | if (found_code && split_point) | |
4718 | return split_block (bb, split_point)->dest; | |
4719 | else | |
4720 | return NULL; | |
4721 | } | |
4722 | ||
6de9cd9a DN |
4723 | /* Return 1 if BB ends with a call, possibly followed by some |
4724 | instructions that must stay with the call, 0 otherwise. */ | |
4725 | ||
4726 | static bool | |
b48d0358 | 4727 | rtl_block_ends_with_call_p (basic_block bb) |
6de9cd9a DN |
4728 | { |
4729 | rtx insn = BB_END (bb); | |
4730 | ||
4b4bf941 | 4731 | while (!CALL_P (insn) |
6de9cd9a | 4732 | && insn != BB_HEAD (bb) |
92ddef69 | 4733 | && (keep_with_call_p (insn) |
b5b8b0ac AO |
4734 | || NOTE_P (insn) |
4735 | || DEBUG_INSN_P (insn))) | |
6de9cd9a | 4736 | insn = PREV_INSN (insn); |
4b4bf941 | 4737 | return (CALL_P (insn)); |
6de9cd9a DN |
4738 | } |
4739 | ||
4740 | /* Return 1 if BB ends with a conditional branch, 0 otherwise. */ | |
4741 | ||
4742 | static bool | |
9678086d | 4743 | rtl_block_ends_with_condjump_p (const_basic_block bb) |
6de9cd9a DN |
4744 | { |
4745 | return any_condjump_p (BB_END (bb)); | |
4746 | } | |
4747 | ||
4748 | /* Return true if we need to add fake edge to exit. | |
4749 | Helper function for rtl_flow_call_edges_add. */ | |
4750 | ||
4751 | static bool | |
9678086d | 4752 | need_fake_edge_p (const_rtx insn) |
6de9cd9a DN |
4753 | { |
4754 | if (!INSN_P (insn)) | |
4755 | return false; | |
4756 | ||
4b4bf941 | 4757 | if ((CALL_P (insn) |
6de9cd9a DN |
4758 | && !SIBLING_CALL_P (insn) |
4759 | && !find_reg_note (insn, REG_NORETURN, NULL) | |
becfd6e5 | 4760 | && !(RTL_CONST_OR_PURE_CALL_P (insn)))) |
6de9cd9a DN |
4761 | return true; |
4762 | ||
4763 | return ((GET_CODE (PATTERN (insn)) == ASM_OPERANDS | |
4764 | && MEM_VOLATILE_P (PATTERN (insn))) | |
4765 | || (GET_CODE (PATTERN (insn)) == PARALLEL | |
4766 | && asm_noperands (insn) != -1 | |
4767 | && MEM_VOLATILE_P (XVECEXP (PATTERN (insn), 0, 0))) | |
4768 | || GET_CODE (PATTERN (insn)) == ASM_INPUT); | |
4769 | } | |
4770 | ||
4771 | /* Add fake edges to the function exit for any non constant and non noreturn | |
4772 | calls, volatile inline assembly in the bitmap of blocks specified by | |
4773 | BLOCKS or to the whole CFG if BLOCKS is zero. Return the number of blocks | |
4774 | that were split. | |
4775 | ||
4776 | The goal is to expose cases in which entering a basic block does not imply | |
4777 | that all subsequent instructions must be executed. */ | |
4778 | ||
4779 | static int | |
4780 | rtl_flow_call_edges_add (sbitmap blocks) | |
4781 | { | |
4782 | int i; | |
4783 | int blocks_split = 0; | |
8b1c6fd7 | 4784 | int last_bb = last_basic_block_for_fn (cfun); |
6de9cd9a DN |
4785 | bool check_last_block = false; |
4786 | ||
0cae8d31 | 4787 | if (n_basic_blocks_for_fn (cfun) == NUM_FIXED_BLOCKS) |
6de9cd9a DN |
4788 | return 0; |
4789 | ||
4790 | if (! blocks) | |
4791 | check_last_block = true; | |
4792 | else | |
fefa31b5 DM |
4793 | check_last_block = bitmap_bit_p (blocks, |
4794 | EXIT_BLOCK_PTR_FOR_FN (cfun)->prev_bb->index); | |
6de9cd9a DN |
4795 | |
4796 | /* In the last basic block, before epilogue generation, there will be | |
4797 | a fallthru edge to EXIT. Special care is required if the last insn | |
4798 | of the last basic block is a call because make_edge folds duplicate | |
4799 | edges, which would result in the fallthru edge also being marked | |
4800 | fake, which would result in the fallthru edge being removed by | |
4801 | remove_fake_edges, which would result in an invalid CFG. | |
4802 | ||
4803 | Moreover, we can't elide the outgoing fake edge, since the block | |
4804 | profiler needs to take this into account in order to solve the minimal | |
4805 | spanning tree in the case that the call doesn't return. | |
4806 | ||
4807 | Handle this by adding a dummy instruction in a new last basic block. */ | |
4808 | if (check_last_block) | |
4809 | { | |
fefa31b5 | 4810 | basic_block bb = EXIT_BLOCK_PTR_FOR_FN (cfun)->prev_bb; |
6de9cd9a DN |
4811 | rtx insn = BB_END (bb); |
4812 | ||
4813 | /* Back up past insns that must be kept in the same block as a call. */ | |
4814 | while (insn != BB_HEAD (bb) | |
4815 | && keep_with_call_p (insn)) | |
4816 | insn = PREV_INSN (insn); | |
4817 | ||
4818 | if (need_fake_edge_p (insn)) | |
4819 | { | |
4820 | edge e; | |
4821 | ||
fefa31b5 | 4822 | e = find_edge (bb, EXIT_BLOCK_PTR_FOR_FN (cfun)); |
9ff3d2de JL |
4823 | if (e) |
4824 | { | |
c41c1387 | 4825 | insert_insn_on_edge (gen_use (const0_rtx), e); |
9ff3d2de JL |
4826 | commit_edge_insertions (); |
4827 | } | |
6de9cd9a DN |
4828 | } |
4829 | } | |
4830 | ||
4831 | /* Now add fake edges to the function exit for any non constant | |
4832 | calls since there is no way that we can determine if they will | |
4833 | return or not... */ | |
4834 | ||
24bd1a0b | 4835 | for (i = NUM_FIXED_BLOCKS; i < last_bb; i++) |
6de9cd9a | 4836 | { |
06e28de2 | 4837 | basic_block bb = BASIC_BLOCK_FOR_FN (cfun, i); |
6de9cd9a DN |
4838 | rtx insn; |
4839 | rtx prev_insn; | |
4840 | ||
4841 | if (!bb) | |
4842 | continue; | |
4843 | ||
d7c028c0 | 4844 | if (blocks && !bitmap_bit_p (blocks, i)) |
6de9cd9a DN |
4845 | continue; |
4846 | ||
4847 | for (insn = BB_END (bb); ; insn = prev_insn) | |
4848 | { | |
4849 | prev_insn = PREV_INSN (insn); | |
4850 | if (need_fake_edge_p (insn)) | |
4851 | { | |
4852 | edge e; | |
4853 | rtx split_at_insn = insn; | |
4854 | ||
4855 | /* Don't split the block between a call and an insn that should | |
c22cacf3 | 4856 | remain in the same block as the call. */ |
4b4bf941 | 4857 | if (CALL_P (insn)) |
6de9cd9a DN |
4858 | while (split_at_insn != BB_END (bb) |
4859 | && keep_with_call_p (NEXT_INSN (split_at_insn))) | |
4860 | split_at_insn = NEXT_INSN (split_at_insn); | |
4861 | ||
4862 | /* The handling above of the final block before the epilogue | |
c22cacf3 | 4863 | should be enough to verify that there is no edge to the exit |
6de9cd9a DN |
4864 | block in CFG already. Calling make_edge in such case would |
4865 | cause us to mark that edge as fake and remove it later. */ | |
4866 | ||
4867 | #ifdef ENABLE_CHECKING | |
4868 | if (split_at_insn == BB_END (bb)) | |
628f6a4e | 4869 | { |
fefa31b5 | 4870 | e = find_edge (bb, EXIT_BLOCK_PTR_FOR_FN (cfun)); |
9ff3d2de | 4871 | gcc_assert (e == NULL); |
628f6a4e | 4872 | } |
6de9cd9a DN |
4873 | #endif |
4874 | ||
4875 | /* Note that the following may create a new basic block | |
4876 | and renumber the existing basic blocks. */ | |
4877 | if (split_at_insn != BB_END (bb)) | |
4878 | { | |
4879 | e = split_block (bb, split_at_insn); | |
4880 | if (e) | |
4881 | blocks_split++; | |
4882 | } | |
4883 | ||
fefa31b5 | 4884 | make_edge (bb, EXIT_BLOCK_PTR_FOR_FN (cfun), EDGE_FAKE); |
6de9cd9a DN |
4885 | } |
4886 | ||
4887 | if (insn == BB_HEAD (bb)) | |
4888 | break; | |
4889 | } | |
4890 | } | |
4891 | ||
4892 | if (blocks_split) | |
4893 | verify_flow_info (); | |
4894 | ||
4895 | return blocks_split; | |
4896 | } | |
4897 | ||
1cb7dfc3 | 4898 | /* Add COMP_RTX as a condition at end of COND_BB. FIRST_HEAD is |
315682fb | 4899 | the conditional branch target, SECOND_HEAD should be the fall-thru |
1cb7dfc3 MH |
4900 | there is no need to handle this here the loop versioning code handles |
4901 | this. the reason for SECON_HEAD is that it is needed for condition | |
4902 | in trees, and this should be of the same type since it is a hook. */ | |
4903 | static void | |
4904 | rtl_lv_add_condition_to_bb (basic_block first_head , | |
c22cacf3 MS |
4905 | basic_block second_head ATTRIBUTE_UNUSED, |
4906 | basic_block cond_bb, void *comp_rtx) | |
1cb7dfc3 MH |
4907 | { |
4908 | rtx label, seq, jump; | |
4909 | rtx op0 = XEXP ((rtx)comp_rtx, 0); | |
4910 | rtx op1 = XEXP ((rtx)comp_rtx, 1); | |
4911 | enum rtx_code comp = GET_CODE ((rtx)comp_rtx); | |
4912 | enum machine_mode mode; | |
4913 | ||
4914 | ||
4915 | label = block_label (first_head); | |
4916 | mode = GET_MODE (op0); | |
4917 | if (mode == VOIDmode) | |
4918 | mode = GET_MODE (op1); | |
4919 | ||
4920 | start_sequence (); | |
4921 | op0 = force_operand (op0, NULL_RTX); | |
4922 | op1 = force_operand (op1, NULL_RTX); | |
4923 | do_compare_rtx_and_jump (op0, op1, comp, 0, | |
40e90eac | 4924 | mode, NULL_RTX, NULL_RTX, label, -1); |
1cb7dfc3 MH |
4925 | jump = get_last_insn (); |
4926 | JUMP_LABEL (jump) = label; | |
4927 | LABEL_NUSES (label)++; | |
4928 | seq = get_insns (); | |
4929 | end_sequence (); | |
4930 | ||
4931 | /* Add the new cond , in the new head. */ | |
c3284718 | 4932 | emit_insn_after (seq, BB_END (cond_bb)); |
1cb7dfc3 MH |
4933 | } |
4934 | ||
4935 | ||
4936 | /* Given a block B with unconditional branch at its end, get the | |
4937 | store the return the branch edge and the fall-thru edge in | |
4938 | BRANCH_EDGE and FALLTHRU_EDGE respectively. */ | |
4939 | static void | |
4940 | rtl_extract_cond_bb_edges (basic_block b, edge *branch_edge, | |
4941 | edge *fallthru_edge) | |
4942 | { | |
4943 | edge e = EDGE_SUCC (b, 0); | |
4944 | ||
4945 | if (e->flags & EDGE_FALLTHRU) | |
4946 | { | |
4947 | *fallthru_edge = e; | |
4948 | *branch_edge = EDGE_SUCC (b, 1); | |
4949 | } | |
4950 | else | |
4951 | { | |
4952 | *branch_edge = e; | |
4953 | *fallthru_edge = EDGE_SUCC (b, 1); | |
4954 | } | |
4955 | } | |
4956 | ||
5e2d947c JH |
4957 | void |
4958 | init_rtl_bb_info (basic_block bb) | |
4959 | { | |
bcc708fc MM |
4960 | gcc_assert (!bb->il.x.rtl); |
4961 | bb->il.x.head_ = NULL; | |
4962 | bb->il.x.rtl = ggc_alloc_cleared_rtl_bb_info (); | |
5e2d947c JH |
4963 | } |
4964 | ||
14fa2cc0 ZD |
4965 | /* Returns true if it is possible to remove edge E by redirecting |
4966 | it to the destination of the other edge from E->src. */ | |
4967 | ||
4968 | static bool | |
9678086d | 4969 | rtl_can_remove_branch_p (const_edge e) |
14fa2cc0 | 4970 | { |
9678086d KG |
4971 | const_basic_block src = e->src; |
4972 | const_basic_block target = EDGE_SUCC (src, EDGE_SUCC (src, 0) == e)->dest; | |
4973 | const_rtx insn = BB_END (src), set; | |
14fa2cc0 ZD |
4974 | |
4975 | /* The conditions are taken from try_redirect_by_replacing_jump. */ | |
fefa31b5 | 4976 | if (target == EXIT_BLOCK_PTR_FOR_FN (cfun)) |
14fa2cc0 ZD |
4977 | return false; |
4978 | ||
4979 | if (e->flags & (EDGE_ABNORMAL_CALL | EDGE_EH)) | |
4980 | return false; | |
4981 | ||
3371a64f | 4982 | if (BB_PARTITION (src) != BB_PARTITION (target)) |
14fa2cc0 ZD |
4983 | return false; |
4984 | ||
4985 | if (!onlyjump_p (insn) | |
4986 | || tablejump_p (insn, NULL, NULL)) | |
4987 | return false; | |
4988 | ||
4989 | set = single_set (insn); | |
4990 | if (!set || side_effects_p (set)) | |
4991 | return false; | |
4992 | ||
4993 | return true; | |
4994 | } | |
4995 | ||
ffe14686 AM |
4996 | static basic_block |
4997 | rtl_duplicate_bb (basic_block bb) | |
4998 | { | |
4999 | bb = cfg_layout_duplicate_bb (bb); | |
5000 | bb->aux = NULL; | |
5001 | return bb; | |
5002 | } | |
5003 | ||
aa4723d7 SB |
5004 | /* Do book-keeping of basic block BB for the profile consistency checker. |
5005 | If AFTER_PASS is 0, do pre-pass accounting, or if AFTER_PASS is 1 | |
5006 | then do post-pass accounting. Store the counting in RECORD. */ | |
5007 | static void | |
5008 | rtl_account_profile_record (basic_block bb, int after_pass, | |
5009 | struct profile_record *record) | |
5010 | { | |
5011 | rtx insn; | |
5012 | FOR_BB_INSNS (bb, insn) | |
5013 | if (INSN_P (insn)) | |
5014 | { | |
5015 | record->size[after_pass] | |
5016 | += insn_rtx_cost (PATTERN (insn), false); | |
0a6a6ac9 | 5017 | if (profile_status_for_fn (cfun) == PROFILE_READ) |
aa4723d7 SB |
5018 | record->time[after_pass] |
5019 | += insn_rtx_cost (PATTERN (insn), true) * bb->count; | |
0a6a6ac9 | 5020 | else if (profile_status_for_fn (cfun) == PROFILE_GUESSED) |
aa4723d7 SB |
5021 | record->time[after_pass] |
5022 | += insn_rtx_cost (PATTERN (insn), true) * bb->frequency; | |
5023 | } | |
5024 | } | |
5025 | ||
9ee634e3 JH |
5026 | /* Implementation of CFG manipulation for linearized RTL. */ |
5027 | struct cfg_hooks rtl_cfg_hooks = { | |
f470c378 | 5028 | "rtl", |
9ee634e3 | 5029 | rtl_verify_flow_info, |
10e9fecc | 5030 | rtl_dump_bb, |
2c895bd1 | 5031 | rtl_dump_bb_for_graph, |
bc35512f | 5032 | rtl_create_basic_block, |
9ee634e3 JH |
5033 | rtl_redirect_edge_and_branch, |
5034 | rtl_redirect_edge_and_branch_force, | |
14fa2cc0 | 5035 | rtl_can_remove_branch_p, |
9ee634e3 JH |
5036 | rtl_delete_block, |
5037 | rtl_split_block, | |
f470c378 | 5038 | rtl_move_block_after, |
bc35512f JH |
5039 | rtl_can_merge_blocks, /* can_merge_blocks_p */ |
5040 | rtl_merge_blocks, | |
6de9cd9a DN |
5041 | rtl_predict_edge, |
5042 | rtl_predicted_by_p, | |
ffe14686 AM |
5043 | cfg_layout_can_duplicate_bb_p, |
5044 | rtl_duplicate_bb, | |
f470c378 ZD |
5045 | rtl_split_edge, |
5046 | rtl_make_forwarder_block, | |
6de9cd9a | 5047 | rtl_tidy_fallthru_edge, |
cf103ca4 | 5048 | rtl_force_nonfallthru, |
6de9cd9a DN |
5049 | rtl_block_ends_with_call_p, |
5050 | rtl_block_ends_with_condjump_p, | |
d9d4706f KH |
5051 | rtl_flow_call_edges_add, |
5052 | NULL, /* execute_on_growing_pred */ | |
1cb7dfc3 MH |
5053 | NULL, /* execute_on_shrinking_pred */ |
5054 | NULL, /* duplicate loop for trees */ | |
5055 | NULL, /* lv_add_condition_to_bb */ | |
5056 | NULL, /* lv_adjust_loop_header_phi*/ | |
5057 | NULL, /* extract_cond_bb_edges */ | |
df92c640 SB |
5058 | NULL, /* flush_pending_stmts */ |
5059 | rtl_block_empty_p, /* block_empty_p */ | |
5060 | rtl_split_block_before_cond_jump, /* split_block_before_cond_jump */ | |
aa4723d7 | 5061 | rtl_account_profile_record, |
9ee634e3 JH |
5062 | }; |
5063 | ||
5064 | /* Implementation of CFG manipulation for cfg layout RTL, where | |
5065 | basic block connected via fallthru edges does not have to be adjacent. | |
5066 | This representation will hopefully become the default one in future | |
5067 | version of the compiler. */ | |
6de9cd9a | 5068 | |
9ee634e3 | 5069 | struct cfg_hooks cfg_layout_rtl_cfg_hooks = { |
f470c378 | 5070 | "cfglayout mode", |
bc35512f | 5071 | rtl_verify_flow_info_1, |
10e9fecc | 5072 | rtl_dump_bb, |
2c895bd1 | 5073 | rtl_dump_bb_for_graph, |
bc35512f | 5074 | cfg_layout_create_basic_block, |
9ee634e3 JH |
5075 | cfg_layout_redirect_edge_and_branch, |
5076 | cfg_layout_redirect_edge_and_branch_force, | |
14fa2cc0 | 5077 | rtl_can_remove_branch_p, |
9ee634e3 JH |
5078 | cfg_layout_delete_block, |
5079 | cfg_layout_split_block, | |
f470c378 | 5080 | rtl_move_block_after, |
bc35512f JH |
5081 | cfg_layout_can_merge_blocks_p, |
5082 | cfg_layout_merge_blocks, | |
6de9cd9a DN |
5083 | rtl_predict_edge, |
5084 | rtl_predicted_by_p, | |
5085 | cfg_layout_can_duplicate_bb_p, | |
5086 | cfg_layout_duplicate_bb, | |
f470c378 ZD |
5087 | cfg_layout_split_edge, |
5088 | rtl_make_forwarder_block, | |
cf103ca4 EB |
5089 | NULL, /* tidy_fallthru_edge */ |
5090 | rtl_force_nonfallthru, | |
6de9cd9a DN |
5091 | rtl_block_ends_with_call_p, |
5092 | rtl_block_ends_with_condjump_p, | |
d9d4706f KH |
5093 | rtl_flow_call_edges_add, |
5094 | NULL, /* execute_on_growing_pred */ | |
1cb7dfc3 MH |
5095 | NULL, /* execute_on_shrinking_pred */ |
5096 | duplicate_loop_to_header_edge, /* duplicate loop for trees */ | |
5097 | rtl_lv_add_condition_to_bb, /* lv_add_condition_to_bb */ | |
5098 | NULL, /* lv_adjust_loop_header_phi*/ | |
5099 | rtl_extract_cond_bb_edges, /* extract_cond_bb_edges */ | |
df92c640 SB |
5100 | NULL, /* flush_pending_stmts */ |
5101 | rtl_block_empty_p, /* block_empty_p */ | |
5102 | rtl_split_block_before_cond_jump, /* split_block_before_cond_jump */ | |
aa4723d7 | 5103 | rtl_account_profile_record, |
9ee634e3 | 5104 | }; |
78bde837 SB |
5105 | |
5106 | #include "gt-cfgrtl.h" |