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ca6c03ca | 1 | /* Control flow graph manipulation code for GNU compiler. |
a945c346 | 2 | Copyright (C) 1987-2024 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 | 27 | - Edge splitting and committing to edges |
2b4efc5d | 28 | insert_insn_on_edge, prepend_insn_to_edge, commit_edge_insertions |
bc35512f JH |
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 | 42 | #include "coretypes.h" |
c7131fb2 | 43 | #include "backend.h" |
957060b5 | 44 | #include "target.h" |
c7131fb2 | 45 | #include "rtl.h" |
957060b5 AM |
46 | #include "tree.h" |
47 | #include "cfghooks.h" | |
c7131fb2 | 48 | #include "df.h" |
957060b5 | 49 | #include "insn-config.h" |
4d0cdd0c | 50 | #include "memmodel.h" |
957060b5 | 51 | #include "emit-rtl.h" |
60393bbc AM |
52 | #include "cfgrtl.h" |
53 | #include "cfganal.h" | |
54 | #include "cfgbuild.h" | |
55 | #include "cfgcleanup.h" | |
60393bbc | 56 | #include "bb-reorder.h" |
0cbd9993 | 57 | #include "rtl-error.h" |
2a34bece | 58 | #include "insn-attr.h" |
36566b39 | 59 | #include "dojump.h" |
ff25ef99 | 60 | #include "expr.h" |
1cb7dfc3 | 61 | #include "cfgloop.h" |
ef330312 | 62 | #include "tree-pass.h" |
013a8899 | 63 | #include "print-rtl.h" |
d6a05b49 RB |
64 | #include "rtl-iter.h" |
65 | #include "gimplify.h" | |
d1471457 JH |
66 | #include "profile.h" |
67 | #include "sreal.h" | |
ca6c03ca | 68 | |
0ecf545c MS |
69 | /* Disable warnings about missing quoting in GCC diagnostics. */ |
70 | #if __GNUC__ >= 10 | |
71 | # pragma GCC diagnostic push | |
72 | # pragma GCC diagnostic ignored "-Wformat-diag" | |
73 | #endif | |
74 | ||
78bde837 SB |
75 | /* Holds the interesting leading and trailing notes for the function. |
76 | Only applicable if the CFG is in cfglayout mode. */ | |
1130d5e3 | 77 | static GTY(()) rtx_insn *cfg_layout_function_footer; |
9152e0aa | 78 | static GTY(()) rtx_insn *cfg_layout_function_header; |
78bde837 | 79 | |
8879d71c | 80 | static rtx_insn *skip_insns_after_block (basic_block); |
78bde837 | 81 | static void record_effective_endpoints (void); |
78bde837 SB |
82 | static void fixup_reorder_chain (void); |
83 | ||
84 | void verify_insn_chain (void); | |
85 | static void fixup_fallthru_exit_predecessor (void); | |
47bd5598 UB |
86 | static bool can_delete_note_p (const rtx_note *); |
87 | static bool can_delete_label_p (const rtx_code_label *); | |
d329e058 | 88 | static basic_block rtl_split_edge (edge); |
f470c378 | 89 | static bool rtl_move_block_after (basic_block, basic_block); |
47bd5598 | 90 | static bool rtl_verify_flow_info (void); |
f470c378 | 91 | static basic_block cfg_layout_split_block (basic_block, void *); |
6de9cd9a | 92 | static edge cfg_layout_redirect_edge_and_branch (edge, basic_block); |
d329e058 AJ |
93 | static basic_block cfg_layout_redirect_edge_and_branch_force (edge, basic_block); |
94 | static void cfg_layout_delete_block (basic_block); | |
95 | static void rtl_delete_block (basic_block); | |
96 | static basic_block rtl_redirect_edge_and_branch_force (edge, basic_block); | |
6de9cd9a | 97 | static edge rtl_redirect_edge_and_branch (edge, basic_block); |
f470c378 | 98 | static basic_block rtl_split_block (basic_block, void *); |
1a817418 | 99 | static void rtl_dump_bb (FILE *, basic_block, int, dump_flags_t); |
47bd5598 | 100 | static bool rtl_verify_flow_info_1 (void); |
f470c378 | 101 | static void rtl_make_forwarder_block (edge); |
4380d5ae | 102 | static bool rtl_bb_info_initialized_p (basic_block bb); |
ca6c03ca JH |
103 | \f |
104 | /* Return true if NOTE is not one of the ones that must be kept paired, | |
5f0d2358 | 105 | so that we may simply delete it. */ |
ca6c03ca | 106 | |
47bd5598 | 107 | static bool |
8879d71c | 108 | can_delete_note_p (const rtx_note *note) |
ca6c03ca | 109 | { |
cd9c1ca8 RH |
110 | switch (NOTE_KIND (note)) |
111 | { | |
112 | case NOTE_INSN_DELETED: | |
113 | case NOTE_INSN_BASIC_BLOCK: | |
114 | case NOTE_INSN_EPILOGUE_BEG: | |
115 | return true; | |
116 | ||
117 | default: | |
118 | return false; | |
119 | } | |
ca6c03ca JH |
120 | } |
121 | ||
122 | /* True if a given label can be deleted. */ | |
123 | ||
47bd5598 | 124 | static bool |
8879d71c | 125 | can_delete_label_p (const rtx_code_label *label) |
ca6c03ca | 126 | { |
5f0d2358 RK |
127 | return (!LABEL_PRESERVE_P (label) |
128 | /* User declared labels must be preserved. */ | |
129 | && LABEL_NAME (label) == 0 | |
6f7eba34 TS |
130 | && !vec_safe_contains<rtx_insn *> (forced_labels, |
131 | const_cast<rtx_code_label *> (label))); | |
ca6c03ca JH |
132 | } |
133 | ||
03fbe718 | 134 | /* Delete INSN by patching it out. */ |
ca6c03ca | 135 | |
03fbe718 | 136 | void |
a29f6a2b | 137 | delete_insn (rtx_insn *insn) |
ca6c03ca | 138 | { |
ca6c03ca JH |
139 | rtx note; |
140 | bool really_delete = true; | |
141 | ||
4b4bf941 | 142 | if (LABEL_P (insn)) |
ca6c03ca JH |
143 | { |
144 | /* Some labels can't be directly removed from the INSN chain, as they | |
c22cacf3 MS |
145 | might be references via variables, constant pool etc. |
146 | Convert them to the special NOTE_INSN_DELETED_LABEL note. */ | |
8879d71c | 147 | if (! can_delete_label_p (as_a <rtx_code_label *> (insn))) |
ca6c03ca JH |
148 | { |
149 | const char *name = LABEL_NAME (insn); | |
5e5df392 | 150 | basic_block bb = BLOCK_FOR_INSN (insn); |
8879d71c | 151 | rtx_insn *bb_note = NEXT_INSN (insn); |
ca6c03ca JH |
152 | |
153 | really_delete = false; | |
154 | PUT_CODE (insn, NOTE); | |
a38e7aa5 | 155 | NOTE_KIND (insn) = NOTE_INSN_DELETED_LABEL; |
6773e15f | 156 | NOTE_DELETED_LABEL_NAME (insn) = name; |
03fbe718 | 157 | |
0f33baa9 | 158 | /* If the note following the label starts a basic block, and the |
5e5df392 | 159 | label is a member of the same basic block, interchange the two. */ |
0f33baa9 TV |
160 | if (bb_note != NULL_RTX |
161 | && NOTE_INSN_BASIC_BLOCK_P (bb_note) | |
5e5df392 TV |
162 | && bb != NULL |
163 | && bb == BLOCK_FOR_INSN (bb_note)) | |
03fbe718 TV |
164 | { |
165 | reorder_insns_nobb (insn, insn, bb_note); | |
1130d5e3 | 166 | BB_HEAD (bb) = bb_note; |
03fbe718 | 167 | if (BB_END (bb) == bb_note) |
1130d5e3 | 168 | BB_END (bb) = insn; |
03fbe718 | 169 | } |
ca6c03ca | 170 | } |
5f0d2358 | 171 | |
b5241a5a | 172 | remove_node_from_insn_list (insn, &nonlocal_goto_handler_labels); |
ca6c03ca JH |
173 | } |
174 | ||
175 | if (really_delete) | |
176 | { | |
cda94cbb | 177 | /* If this insn has already been deleted, something is very wrong. */ |
4654c0cf | 178 | gcc_assert (!insn->deleted ()); |
1f397f45 SB |
179 | if (INSN_P (insn)) |
180 | df_insn_delete (insn); | |
ca6c03ca | 181 | remove_insn (insn); |
4654c0cf | 182 | insn->set_deleted (); |
ca6c03ca JH |
183 | } |
184 | ||
185 | /* If deleting a jump, decrement the use count of the label. Deleting | |
186 | the label itself should happen in the normal course of block merging. */ | |
cf7c4aa6 | 187 | if (JUMP_P (insn)) |
9295a326 | 188 | { |
cf7c4aa6 HPN |
189 | if (JUMP_LABEL (insn) |
190 | && LABEL_P (JUMP_LABEL (insn))) | |
191 | LABEL_NUSES (JUMP_LABEL (insn))--; | |
192 | ||
193 | /* If there are more targets, remove them too. */ | |
194 | while ((note | |
195 | = find_reg_note (insn, REG_LABEL_TARGET, NULL_RTX)) != NULL_RTX | |
4b4bf941 | 196 | && LABEL_P (XEXP (note, 0))) |
9295a326 JZ |
197 | { |
198 | LABEL_NUSES (XEXP (note, 0))--; | |
199 | remove_note (insn, note); | |
200 | } | |
201 | } | |
ca6c03ca | 202 | |
cf7c4aa6 HPN |
203 | /* Also if deleting any insn that references a label as an operand. */ |
204 | while ((note = find_reg_note (insn, REG_LABEL_OPERAND, NULL_RTX)) != NULL_RTX | |
205 | && LABEL_P (XEXP (note, 0))) | |
206 | { | |
207 | LABEL_NUSES (XEXP (note, 0))--; | |
208 | remove_note (insn, note); | |
209 | } | |
210 | ||
95c43227 | 211 | if (rtx_jump_table_data *table = dyn_cast <rtx_jump_table_data *> (insn)) |
ca6c03ca | 212 | { |
95c43227 DM |
213 | rtvec vec = table->get_labels (); |
214 | int len = GET_NUM_ELEM (vec); | |
ca6c03ca JH |
215 | int i; |
216 | ||
217 | for (i = 0; i < len; i++) | |
a124fcda | 218 | { |
95c43227 | 219 | rtx label = XEXP (RTVEC_ELT (vec, i), 0); |
a124fcda RH |
220 | |
221 | /* When deleting code in bulk (e.g. removing many unreachable | |
222 | blocks) we can delete a label that's a target of the vector | |
223 | before deleting the vector itself. */ | |
4b4bf941 | 224 | if (!NOTE_P (label)) |
a124fcda RH |
225 | LABEL_NUSES (label)--; |
226 | } | |
ca6c03ca | 227 | } |
ca6c03ca JH |
228 | } |
229 | ||
98ccd1d7 IE |
230 | /* Like delete_insn but also purge dead edges from BB. |
231 | Return true if any edges are eliminated. */ | |
9ed7b221 | 232 | |
98ccd1d7 | 233 | bool |
373fc786 | 234 | delete_insn_and_edges (rtx_insn *insn) |
3dec4024 | 235 | { |
3dec4024 JH |
236 | bool purge = false; |
237 | ||
37a8220f | 238 | if (NONDEBUG_INSN_P (insn) && BLOCK_FOR_INSN (insn)) |
c41884a0 JJ |
239 | { |
240 | basic_block bb = BLOCK_FOR_INSN (insn); | |
241 | if (BB_END (bb) == insn) | |
242 | purge = true; | |
243 | else if (DEBUG_INSN_P (BB_END (bb))) | |
244 | for (rtx_insn *dinsn = NEXT_INSN (insn); | |
245 | DEBUG_INSN_P (dinsn); dinsn = NEXT_INSN (dinsn)) | |
246 | if (BB_END (bb) == dinsn) | |
247 | { | |
248 | purge = true; | |
249 | break; | |
250 | } | |
251 | } | |
03fbe718 | 252 | delete_insn (insn); |
3dec4024 | 253 | if (purge) |
98ccd1d7 IE |
254 | return purge_dead_edges (BLOCK_FOR_INSN (insn)); |
255 | return false; | |
3dec4024 JH |
256 | } |
257 | ||
ca6c03ca | 258 | /* Unlink a chain of insns between START and FINISH, leaving notes |
a7b87f73 ZD |
259 | that must be paired. If CLEAR_BB is true, we set bb field for |
260 | insns that cannot be removed to NULL. */ | |
ca6c03ca JH |
261 | |
262 | void | |
2d93cd20 | 263 | delete_insn_chain (rtx start, rtx_insn *finish, bool clear_bb) |
ca6c03ca | 264 | { |
5f0d2358 RK |
265 | /* Unchain the insns one by one. It would be quicker to delete all of these |
266 | with a single unchaining, rather than one at a time, but we need to keep | |
267 | the NOTE's. */ | |
2d93cd20 | 268 | rtx_insn *current = finish; |
ca6c03ca JH |
269 | while (1) |
270 | { | |
2d93cd20 | 271 | rtx_insn *prev = PREV_INSN (current); |
8879d71c | 272 | if (NOTE_P (current) && !can_delete_note_p (as_a <rtx_note *> (current))) |
ca6c03ca JH |
273 | ; |
274 | else | |
03fbe718 | 275 | delete_insn (current); |
ca6c03ca | 276 | |
4654c0cf | 277 | if (clear_bb && !current->deleted ()) |
03fbe718 | 278 | set_block_for_insn (current, NULL); |
a7b87f73 | 279 | |
03fbe718 | 280 | if (current == start) |
ca6c03ca | 281 | break; |
03fbe718 | 282 | current = prev; |
ca6c03ca JH |
283 | } |
284 | } | |
285 | \f | |
5f0d2358 RK |
286 | /* Create a new basic block consisting of the instructions between HEAD and END |
287 | inclusive. This function is designed to allow fast BB construction - reuses | |
288 | the note and basic block struct in BB_NOTE, if any and do not grow | |
289 | BASIC_BLOCK chain and should be used directly only by CFG construction code. | |
290 | END can be NULL in to create new empty basic block before HEAD. Both END | |
918ed612 ZD |
291 | and HEAD can be NULL to create basic block at the end of INSN chain. |
292 | AFTER is the basic block we should be put after. */ | |
ca6c03ca JH |
293 | |
294 | basic_block | |
e00022e9 | 295 | create_basic_block_structure (rtx_insn *head, rtx_insn *end, rtx_note *bb_note, |
66e8df53 | 296 | basic_block after) |
ca6c03ca JH |
297 | { |
298 | basic_block bb; | |
299 | ||
300 | if (bb_note | |
ca6c03ca JH |
301 | && (bb = NOTE_BASIC_BLOCK (bb_note)) != NULL |
302 | && bb->aux == NULL) | |
303 | { | |
304 | /* If we found an existing note, thread it back onto the chain. */ | |
305 | ||
fee3e72c | 306 | rtx_insn *after; |
ca6c03ca | 307 | |
4b4bf941 | 308 | if (LABEL_P (head)) |
ca6c03ca JH |
309 | after = head; |
310 | else | |
311 | { | |
312 | after = PREV_INSN (head); | |
313 | head = bb_note; | |
314 | } | |
315 | ||
316 | if (after != bb_note && NEXT_INSN (after) != bb_note) | |
ba4f7968 | 317 | reorder_insns_nobb (bb_note, bb_note, after); |
ca6c03ca JH |
318 | } |
319 | else | |
320 | { | |
321 | /* Otherwise we must create a note and a basic block structure. */ | |
322 | ||
323 | bb = alloc_block (); | |
324 | ||
5e2d947c | 325 | init_rtl_bb_info (bb); |
ca6c03ca | 326 | if (!head && !end) |
5f0d2358 RK |
327 | head = end = bb_note |
328 | = emit_note_after (NOTE_INSN_BASIC_BLOCK, get_last_insn ()); | |
4b4bf941 | 329 | else if (LABEL_P (head) && end) |
ca6c03ca JH |
330 | { |
331 | bb_note = emit_note_after (NOTE_INSN_BASIC_BLOCK, head); | |
332 | if (head == end) | |
333 | end = bb_note; | |
334 | } | |
335 | else | |
336 | { | |
337 | bb_note = emit_note_before (NOTE_INSN_BASIC_BLOCK, head); | |
338 | head = bb_note; | |
339 | if (!end) | |
340 | end = head; | |
341 | } | |
5f0d2358 | 342 | |
ca6c03ca JH |
343 | NOTE_BASIC_BLOCK (bb_note) = bb; |
344 | } | |
345 | ||
346 | /* Always include the bb note in the block. */ | |
347 | if (NEXT_INSN (end) == bb_note) | |
348 | end = bb_note; | |
349 | ||
1130d5e3 DM |
350 | BB_HEAD (bb) = head; |
351 | BB_END (bb) = end; | |
8b1c6fd7 | 352 | bb->index = last_basic_block_for_fn (cfun)++; |
5e2d947c | 353 | bb->flags = BB_NEW | BB_RTL; |
918ed612 | 354 | link_block (bb, after); |
557c4b49 | 355 | SET_BASIC_BLOCK_FOR_FN (cfun, bb->index, bb); |
6fb5fa3c | 356 | df_bb_refs_record (bb->index, false); |
ba4f7968 | 357 | update_bb_for_insn (bb); |
076c7ab8 | 358 | BB_SET_PARTITION (bb, BB_UNPARTITIONED); |
ca6c03ca JH |
359 | |
360 | /* Tag the block so that we know it has been used when considering | |
361 | other basic block notes. */ | |
362 | bb->aux = bb; | |
363 | ||
364 | return bb; | |
365 | } | |
366 | ||
5f0d2358 | 367 | /* Create new basic block consisting of instructions in between HEAD and END |
ffe14686 AM |
368 | and place it to the BB chain after block AFTER. END can be NULL to |
369 | create a new empty basic block before HEAD. Both END and HEAD can be | |
370 | NULL to create basic block at the end of INSN chain. */ | |
ca6c03ca | 371 | |
bc35512f JH |
372 | static basic_block |
373 | rtl_create_basic_block (void *headp, void *endp, basic_block after) | |
ca6c03ca | 374 | { |
e00022e9 DM |
375 | rtx_insn *head = (rtx_insn *) headp; |
376 | rtx_insn *end = (rtx_insn *) endp; | |
ca6c03ca | 377 | basic_block bb; |
0b17ab2f | 378 | |
7eca0767 | 379 | /* Grow the basic block array if needed. */ |
8b1c6fd7 DM |
380 | if ((size_t) last_basic_block_for_fn (cfun) |
381 | >= basic_block_info_for_fn (cfun)->length ()) | |
a292e31d ML |
382 | vec_safe_grow_cleared (basic_block_info_for_fn (cfun), |
383 | last_basic_block_for_fn (cfun) + 1); | |
0b17ab2f | 384 | |
0cae8d31 | 385 | n_basic_blocks_for_fn (cfun)++; |
ca6c03ca | 386 | |
852c6ec7 | 387 | bb = create_basic_block_structure (head, end, NULL, after); |
ca6c03ca JH |
388 | bb->aux = NULL; |
389 | return bb; | |
390 | } | |
bc35512f JH |
391 | |
392 | static basic_block | |
393 | cfg_layout_create_basic_block (void *head, void *end, basic_block after) | |
394 | { | |
395 | basic_block newbb = rtl_create_basic_block (head, end, after); | |
396 | ||
bc35512f JH |
397 | return newbb; |
398 | } | |
ca6c03ca JH |
399 | \f |
400 | /* Delete the insns in a (non-live) block. We physically delete every | |
401 | non-deleted-note insn, and update the flow graph appropriately. | |
402 | ||
403 | Return nonzero if we deleted an exception handler. */ | |
404 | ||
405 | /* ??? Preserving all such notes strikes me as wrong. It would be nice | |
406 | to post-process the stream to remove empty blocks, loops, ranges, etc. */ | |
407 | ||
f0fda11c | 408 | static void |
d329e058 | 409 | rtl_delete_block (basic_block b) |
ca6c03ca | 410 | { |
8879d71c | 411 | rtx_insn *insn, *end; |
ca6c03ca JH |
412 | |
413 | /* If the head of this block is a CODE_LABEL, then it might be the | |
f39e46ba SB |
414 | label for an exception handler which can't be reached. We need |
415 | to remove the label from the exception_handler_label list. */ | |
a813c111 | 416 | insn = BB_HEAD (b); |
ca6c03ca | 417 | |
96370780 | 418 | end = get_last_bb_insn (b); |
ca6c03ca JH |
419 | |
420 | /* Selectively delete the entire chain. */ | |
1130d5e3 | 421 | BB_HEAD (b) = NULL; |
a7b87f73 ZD |
422 | delete_insn_chain (insn, end, true); |
423 | ||
6fb5fa3c DB |
424 | |
425 | if (dump_file) | |
426 | fprintf (dump_file, "deleting block %d\n", b->index); | |
427 | df_bb_delete (b->index); | |
ca6c03ca JH |
428 | } |
429 | \f | |
852c6ec7 | 430 | /* Records the basic block struct in BLOCK_FOR_INSN for every insn. */ |
ca6c03ca JH |
431 | |
432 | void | |
d329e058 | 433 | compute_bb_for_insn (void) |
ca6c03ca | 434 | { |
e0082a72 | 435 | basic_block bb; |
ca6c03ca | 436 | |
11cd3bed | 437 | FOR_EACH_BB_FN (bb, cfun) |
ca6c03ca | 438 | { |
8879d71c DM |
439 | rtx_insn *end = BB_END (bb); |
440 | rtx_insn *insn; | |
ca6c03ca | 441 | |
a813c111 | 442 | for (insn = BB_HEAD (bb); ; insn = NEXT_INSN (insn)) |
ca6c03ca | 443 | { |
ba4f7968 | 444 | BLOCK_FOR_INSN (insn) = bb; |
ca6c03ca JH |
445 | if (insn == end) |
446 | break; | |
ca6c03ca JH |
447 | } |
448 | } | |
449 | } | |
450 | ||
451 | /* Release the basic_block_for_insn array. */ | |
452 | ||
47bd5598 | 453 | void |
d329e058 | 454 | free_bb_for_insn (void) |
ca6c03ca | 455 | { |
8879d71c | 456 | rtx_insn *insn; |
ba4f7968 | 457 | for (insn = get_insns (); insn; insn = NEXT_INSN (insn)) |
4b4bf941 | 458 | if (!BARRIER_P (insn)) |
ba4f7968 | 459 | BLOCK_FOR_INSN (insn) = NULL; |
ca6c03ca JH |
460 | } |
461 | ||
27a4cd48 DM |
462 | namespace { |
463 | ||
464 | const pass_data pass_data_free_cfg = | |
465 | { | |
466 | RTL_PASS, /* type */ | |
467 | "*free_cfg", /* name */ | |
468 | OPTGROUP_NONE, /* optinfo_flags */ | |
27a4cd48 DM |
469 | TV_NONE, /* tv_id */ |
470 | 0, /* properties_required */ | |
471 | 0, /* properties_provided */ | |
472 | PROP_cfg, /* properties_destroyed */ | |
473 | 0, /* todo_flags_start */ | |
474 | 0, /* todo_flags_finish */ | |
ef330312 PB |
475 | }; |
476 | ||
27a4cd48 DM |
477 | class pass_free_cfg : public rtl_opt_pass |
478 | { | |
479 | public: | |
c3284718 RS |
480 | pass_free_cfg (gcc::context *ctxt) |
481 | : rtl_opt_pass (pass_data_free_cfg, ctxt) | |
27a4cd48 DM |
482 | {} |
483 | ||
484 | /* opt_pass methods: */ | |
725793af | 485 | unsigned int execute (function *) final override; |
27a4cd48 DM |
486 | |
487 | }; // class pass_free_cfg | |
488 | ||
be55bfe6 TS |
489 | unsigned int |
490 | pass_free_cfg::execute (function *) | |
491 | { | |
e53b6e56 | 492 | /* The resource.cc machinery uses DF but the CFG isn't guaranteed to be |
be55bfe6 | 493 | valid at that point so it would be too late to call df_analyze. */ |
e90bedf5 | 494 | if (DELAY_SLOTS && optimize > 0 && flag_delayed_branch) |
be55bfe6 TS |
495 | { |
496 | df_note_add_problem (); | |
497 | df_analyze (); | |
498 | } | |
be55bfe6 TS |
499 | |
500 | if (crtl->has_bb_partition) | |
501 | insert_section_boundary_note (); | |
502 | ||
503 | free_bb_for_insn (); | |
504 | return 0; | |
505 | } | |
506 | ||
27a4cd48 DM |
507 | } // anon namespace |
508 | ||
509 | rtl_opt_pass * | |
510 | make_pass_free_cfg (gcc::context *ctxt) | |
511 | { | |
512 | return new pass_free_cfg (ctxt); | |
513 | } | |
514 | ||
91278841 | 515 | /* Return RTX to emit after when we want to emit code on the entry of function. */ |
8a2e8325 | 516 | rtx_insn * |
91278841 AP |
517 | entry_of_function (void) |
518 | { | |
0cae8d31 | 519 | return (n_basic_blocks_for_fn (cfun) > NUM_FIXED_BLOCKS ? |
fefa31b5 | 520 | BB_HEAD (ENTRY_BLOCK_PTR_FOR_FN (cfun)->next_bb) : get_insns ()); |
91278841 AP |
521 | } |
522 | ||
11b904a1 BS |
523 | /* Emit INSN at the entry point of the function, ensuring that it is only |
524 | executed once per function. */ | |
525 | void | |
526 | emit_insn_at_entry (rtx insn) | |
527 | { | |
fefa31b5 | 528 | edge_iterator ei = ei_start (ENTRY_BLOCK_PTR_FOR_FN (cfun)->succs); |
11b904a1 | 529 | edge e = ei_safe_edge (ei); |
5419bc7f | 530 | gcc_assert (e->flags & EDGE_FALLTHRU); |
11b904a1 BS |
531 | |
532 | insert_insn_on_edge (insn, e); | |
533 | commit_edge_insertions (); | |
534 | } | |
535 | ||
6c3d0e31 | 536 | /* Update BLOCK_FOR_INSN of insns between BEGIN and END |
b8698a0f | 537 | (or BARRIER if found) and notify df of the bb change. |
6c3d0e31 SP |
538 | The insn chain range is inclusive |
539 | (i.e. both BEGIN and END will be updated. */ | |
ca6c03ca | 540 | |
6c3d0e31 | 541 | static void |
8879d71c | 542 | update_bb_for_insn_chain (rtx_insn *begin, rtx_insn *end, basic_block bb) |
ca6c03ca | 543 | { |
8879d71c | 544 | rtx_insn *insn; |
ca6c03ca | 545 | |
6c3d0e31 SP |
546 | end = NEXT_INSN (end); |
547 | for (insn = begin; insn != end; insn = NEXT_INSN (insn)) | |
63642d5a AO |
548 | if (!BARRIER_P (insn)) |
549 | df_insn_change_bb (insn, bb); | |
ca6c03ca | 550 | } |
6c3d0e31 SP |
551 | |
552 | /* Update BLOCK_FOR_INSN of insns in BB to BB, | |
553 | and notify df of the change. */ | |
554 | ||
555 | void | |
556 | update_bb_for_insn (basic_block bb) | |
557 | { | |
558 | update_bb_for_insn_chain (BB_HEAD (bb), BB_END (bb), bb); | |
559 | } | |
560 | ||
532aafad | 561 | \f |
1008df90 | 562 | /* Like active_insn_p, except keep the return value use or clobber around |
532aafad SB |
563 | even after reload. */ |
564 | ||
565 | static bool | |
8879d71c | 566 | flow_active_insn_p (const rtx_insn *insn) |
532aafad SB |
567 | { |
568 | if (active_insn_p (insn)) | |
569 | return true; | |
570 | ||
571 | /* A clobber of the function return value exists for buggy | |
572 | programs that fail to return a value. Its effect is to | |
573 | keep the return value from being live across the entire | |
574 | function. If we allow it to be skipped, we introduce the | |
1008df90 JJ |
575 | possibility for register lifetime confusion. |
576 | Similarly, keep a USE of the function return value, otherwise | |
577 | the USE is dropped and we could fail to thread jump if USE | |
578 | appears on some paths and not on others, see PR90257. */ | |
579 | if ((GET_CODE (PATTERN (insn)) == CLOBBER | |
580 | || GET_CODE (PATTERN (insn)) == USE) | |
532aafad SB |
581 | && REG_P (XEXP (PATTERN (insn), 0)) |
582 | && REG_FUNCTION_VALUE_P (XEXP (PATTERN (insn), 0))) | |
583 | return true; | |
584 | ||
585 | return false; | |
586 | } | |
587 | ||
588 | /* Return true if the block has no effect and only forwards control flow to | |
589 | its single destination. */ | |
532aafad SB |
590 | |
591 | bool | |
2407343c | 592 | contains_no_active_insn_p (const_basic_block bb) |
532aafad | 593 | { |
8879d71c | 594 | rtx_insn *insn; |
532aafad | 595 | |
4833f561 JJ |
596 | if (bb == EXIT_BLOCK_PTR_FOR_FN (cfun) |
597 | || bb == ENTRY_BLOCK_PTR_FOR_FN (cfun) | |
598 | || !single_succ_p (bb) | |
599 | || (single_succ_edge (bb)->flags & EDGE_FAKE) != 0) | |
532aafad SB |
600 | return false; |
601 | ||
2407343c JR |
602 | for (insn = BB_HEAD (bb); insn != BB_END (bb); insn = NEXT_INSN (insn)) |
603 | if (INSN_P (insn) && flow_active_insn_p (insn)) | |
604 | return false; | |
605 | ||
606 | return (!INSN_P (insn) | |
607 | || (JUMP_P (insn) && simplejump_p (insn)) | |
608 | || !flow_active_insn_p (insn)); | |
609 | } | |
610 | ||
611 | /* Likewise, but protect loop latches, headers and preheaders. */ | |
612 | /* FIXME: Make this a cfg hook. */ | |
613 | ||
614 | bool | |
615 | forwarder_block_p (const_basic_block bb) | |
616 | { | |
617 | if (!contains_no_active_insn_p (bb)) | |
618 | return false; | |
619 | ||
532aafad SB |
620 | /* Protect loop latches, headers and preheaders. */ |
621 | if (current_loops) | |
622 | { | |
623 | basic_block dest; | |
624 | if (bb->loop_father->header == bb) | |
625 | return false; | |
626 | dest = EDGE_SUCC (bb, 0)->dest; | |
627 | if (dest->loop_father->header == dest) | |
628 | return false; | |
629 | } | |
630 | ||
2407343c | 631 | return true; |
532aafad SB |
632 | } |
633 | ||
634 | /* Return nonzero if we can reach target from src by falling through. */ | |
d7b6661b | 635 | /* FIXME: Make this a cfg hook, the result is only valid in cfgrtl mode. */ |
532aafad SB |
636 | |
637 | bool | |
638 | can_fallthru (basic_block src, basic_block target) | |
639 | { | |
8879d71c DM |
640 | rtx_insn *insn = BB_END (src); |
641 | rtx_insn *insn2; | |
532aafad SB |
642 | edge e; |
643 | edge_iterator ei; | |
644 | ||
fefa31b5 | 645 | if (target == EXIT_BLOCK_PTR_FOR_FN (cfun)) |
532aafad SB |
646 | return true; |
647 | if (src->next_bb != target) | |
d7b6661b SB |
648 | return false; |
649 | ||
650 | /* ??? Later we may add code to move jump tables offline. */ | |
651 | if (tablejump_p (insn, NULL, NULL)) | |
652 | return false; | |
653 | ||
532aafad | 654 | FOR_EACH_EDGE (e, ei, src->succs) |
fefa31b5 | 655 | if (e->dest == EXIT_BLOCK_PTR_FOR_FN (cfun) |
532aafad | 656 | && e->flags & EDGE_FALLTHRU) |
d7b6661b | 657 | return false; |
532aafad SB |
658 | |
659 | insn2 = BB_HEAD (target); | |
d7b6661b | 660 | if (!active_insn_p (insn2)) |
532aafad SB |
661 | insn2 = next_active_insn (insn2); |
662 | ||
532aafad SB |
663 | return next_active_insn (insn) == insn2; |
664 | } | |
665 | ||
666 | /* Return nonzero if we could reach target from src by falling through, | |
667 | if the target was made adjacent. If we already have a fall-through | |
668 | edge to the exit block, we can't do that. */ | |
669 | static bool | |
670 | could_fall_through (basic_block src, basic_block target) | |
671 | { | |
672 | edge e; | |
673 | edge_iterator ei; | |
674 | ||
fefa31b5 | 675 | if (target == EXIT_BLOCK_PTR_FOR_FN (cfun)) |
532aafad SB |
676 | return true; |
677 | FOR_EACH_EDGE (e, ei, src->succs) | |
fefa31b5 | 678 | if (e->dest == EXIT_BLOCK_PTR_FOR_FN (cfun) |
532aafad SB |
679 | && e->flags & EDGE_FALLTHRU) |
680 | return 0; | |
681 | return true; | |
682 | } | |
ca6c03ca | 683 | \f |
ef2be249 | 684 | /* Return the NOTE_INSN_BASIC_BLOCK of BB. */ |
ed270997 | 685 | rtx_note * |
ef2be249 RS |
686 | bb_note (basic_block bb) |
687 | { | |
8879d71c | 688 | rtx_insn *note; |
ef2be249 RS |
689 | |
690 | note = BB_HEAD (bb); | |
691 | if (LABEL_P (note)) | |
692 | note = NEXT_INSN (note); | |
693 | ||
694 | gcc_assert (NOTE_INSN_BASIC_BLOCK_P (note)); | |
ed270997 | 695 | return as_a <rtx_note *> (note); |
ef2be249 RS |
696 | } |
697 | ||
6fb5fa3c DB |
698 | /* Return the INSN immediately following the NOTE_INSN_BASIC_BLOCK |
699 | note associated with the BLOCK. */ | |
700 | ||
8879d71c | 701 | static rtx_insn * |
6fb5fa3c DB |
702 | first_insn_after_basic_block_note (basic_block block) |
703 | { | |
8879d71c | 704 | rtx_insn *insn; |
6fb5fa3c DB |
705 | |
706 | /* Get the first instruction in the block. */ | |
707 | insn = BB_HEAD (block); | |
708 | ||
709 | if (insn == NULL_RTX) | |
8879d71c | 710 | return NULL; |
6fb5fa3c DB |
711 | if (LABEL_P (insn)) |
712 | insn = NEXT_INSN (insn); | |
713 | gcc_assert (NOTE_INSN_BASIC_BLOCK_P (insn)); | |
714 | ||
715 | return NEXT_INSN (insn); | |
716 | } | |
717 | ||
2b9c63a2 FY |
718 | /* Creates a new basic block just after basic block BB by splitting |
719 | everything after specified instruction INSNP. */ | |
ca6c03ca | 720 | |
f470c378 | 721 | static basic_block |
d329e058 | 722 | rtl_split_block (basic_block bb, void *insnp) |
ca6c03ca JH |
723 | { |
724 | basic_block new_bb; | |
8879d71c | 725 | rtx_insn *insn = (rtx_insn *) insnp; |
f470c378 | 726 | edge e; |
628f6a4e | 727 | edge_iterator ei; |
ca6c03ca | 728 | |
f470c378 ZD |
729 | if (!insn) |
730 | { | |
731 | insn = first_insn_after_basic_block_note (bb); | |
732 | ||
733 | if (insn) | |
b5b8b0ac | 734 | { |
8879d71c | 735 | rtx_insn *next = insn; |
b5b8b0ac AO |
736 | |
737 | insn = PREV_INSN (insn); | |
738 | ||
739 | /* If the block contains only debug insns, insn would have | |
740 | been NULL in a non-debug compilation, and then we'd end | |
741 | up emitting a DELETED note. For -fcompare-debug | |
742 | stability, emit the note too. */ | |
743 | if (insn != BB_END (bb) | |
744 | && DEBUG_INSN_P (next) | |
745 | && DEBUG_INSN_P (BB_END (bb))) | |
746 | { | |
747 | while (next != BB_END (bb) && DEBUG_INSN_P (next)) | |
748 | next = NEXT_INSN (next); | |
749 | ||
750 | if (next == BB_END (bb)) | |
751 | emit_note_after (NOTE_INSN_DELETED, next); | |
752 | } | |
753 | } | |
f470c378 ZD |
754 | else |
755 | insn = get_last_insn (); | |
756 | } | |
757 | ||
758 | /* We probably should check type of the insn so that we do not create | |
759 | inconsistent cfg. It is checked in verify_flow_info anyway, so do not | |
760 | bother. */ | |
761 | if (insn == BB_END (bb)) | |
762 | emit_note_after (NOTE_INSN_DELETED, insn); | |
ca6c03ca JH |
763 | |
764 | /* Create the new basic block. */ | |
a813c111 | 765 | new_bb = create_basic_block (NEXT_INSN (insn), BB_END (bb), bb); |
076c7ab8 | 766 | BB_COPY_PARTITION (new_bb, bb); |
1130d5e3 | 767 | BB_END (bb) = insn; |
ca6c03ca JH |
768 | |
769 | /* Redirect the outgoing edges. */ | |
628f6a4e BE |
770 | new_bb->succs = bb->succs; |
771 | bb->succs = NULL; | |
772 | FOR_EACH_EDGE (e, ei, new_bb->succs) | |
ca6c03ca JH |
773 | e->src = new_bb; |
774 | ||
6fb5fa3c DB |
775 | /* The new block starts off being dirty. */ |
776 | df_set_bb_dirty (bb); | |
f470c378 | 777 | return new_bb; |
bc35512f JH |
778 | } |
779 | ||
430dca62 JJ |
780 | /* Return true if LOC1 and LOC2 are equivalent for |
781 | unique_locus_on_edge_between_p purposes. */ | |
782 | ||
783 | static bool | |
784 | loc_equal (location_t loc1, location_t loc2) | |
785 | { | |
786 | if (loc1 == loc2) | |
787 | return true; | |
788 | ||
789 | expanded_location loce1 = expand_location (loc1); | |
790 | expanded_location loce2 = expand_location (loc2); | |
791 | ||
792 | if (loce1.line != loce2.line | |
793 | || loce1.column != loce2.column | |
794 | || loce1.data != loce2.data) | |
795 | return false; | |
796 | if (loce1.file == loce2.file) | |
797 | return true; | |
798 | return (loce1.file != NULL | |
799 | && loce2.file != NULL | |
800 | && filename_cmp (loce1.file, loce2.file) == 0); | |
801 | } | |
802 | ||
9be94227 EB |
803 | /* Return true if the single edge between blocks A and B is the only place |
804 | in RTL which holds some unique locus. */ | |
805 | ||
806 | static bool | |
807 | unique_locus_on_edge_between_p (basic_block a, basic_block b) | |
808 | { | |
5368224f | 809 | const location_t goto_locus = EDGE_SUCC (a, 0)->goto_locus; |
8879d71c | 810 | rtx_insn *insn, *end; |
9be94227 | 811 | |
2f13f2de | 812 | if (LOCATION_LOCUS (goto_locus) == UNKNOWN_LOCATION) |
9be94227 EB |
813 | return false; |
814 | ||
815 | /* First scan block A backward. */ | |
816 | insn = BB_END (a); | |
817 | end = PREV_INSN (BB_HEAD (a)); | |
5368224f | 818 | while (insn != end && (!NONDEBUG_INSN_P (insn) || !INSN_HAS_LOCATION (insn))) |
9be94227 EB |
819 | insn = PREV_INSN (insn); |
820 | ||
430dca62 | 821 | if (insn != end && loc_equal (INSN_LOCATION (insn), goto_locus)) |
9be94227 EB |
822 | return false; |
823 | ||
824 | /* Then scan block B forward. */ | |
825 | insn = BB_HEAD (b); | |
826 | if (insn) | |
827 | { | |
828 | end = NEXT_INSN (BB_END (b)); | |
829 | while (insn != end && !NONDEBUG_INSN_P (insn)) | |
830 | insn = NEXT_INSN (insn); | |
831 | ||
5368224f | 832 | if (insn != end && INSN_HAS_LOCATION (insn) |
430dca62 | 833 | && loc_equal (INSN_LOCATION (insn), goto_locus)) |
9be94227 EB |
834 | return false; |
835 | } | |
836 | ||
837 | return true; | |
838 | } | |
839 | ||
840 | /* If the single edge between blocks A and B is the only place in RTL which | |
841 | holds some unique locus, emit a nop with that locus between the blocks. */ | |
842 | ||
843 | static void | |
844 | emit_nop_for_unique_locus_between (basic_block a, basic_block b) | |
845 | { | |
846 | if (!unique_locus_on_edge_between_p (a, b)) | |
847 | return; | |
848 | ||
1130d5e3 | 849 | BB_END (a) = emit_insn_after_noloc (gen_nop (), BB_END (a), a); |
5368224f | 850 | INSN_LOCATION (BB_END (a)) = EDGE_SUCC (a, 0)->goto_locus; |
9be94227 EB |
851 | } |
852 | ||
ca6c03ca | 853 | /* Blocks A and B are to be merged into a single block A. The insns |
bc35512f | 854 | are already contiguous. */ |
ca6c03ca | 855 | |
bc35512f JH |
856 | static void |
857 | rtl_merge_blocks (basic_block a, basic_block b) | |
ca6c03ca | 858 | { |
7792f13c EB |
859 | /* If B is a forwarder block whose outgoing edge has no location, we'll |
860 | propagate the locus of the edge between A and B onto it. */ | |
861 | const bool forward_edge_locus | |
862 | = (b->flags & BB_FORWARDER_BLOCK) != 0 | |
863 | && LOCATION_LOCUS (EDGE_SUCC (b, 0)->goto_locus) == UNKNOWN_LOCATION; | |
8879d71c DM |
864 | rtx_insn *b_head = BB_HEAD (b), *b_end = BB_END (b), *a_end = BB_END (a); |
865 | rtx_insn *del_first = NULL, *del_last = NULL; | |
866 | rtx_insn *b_debug_start = b_end, *b_debug_end = b_end; | |
47bd5598 | 867 | bool b_empty = false; |
ca6c03ca | 868 | |
6fb5fa3c | 869 | if (dump_file) |
50a36e42 EB |
870 | fprintf (dump_file, "Merging block %d into block %d...\n", b->index, |
871 | a->index); | |
6fb5fa3c | 872 | |
b5b8b0ac AO |
873 | while (DEBUG_INSN_P (b_end)) |
874 | b_end = PREV_INSN (b_debug_start = b_end); | |
875 | ||
ca6c03ca | 876 | /* If there was a CODE_LABEL beginning B, delete it. */ |
4b4bf941 | 877 | if (LABEL_P (b_head)) |
ca6c03ca JH |
878 | { |
879 | /* Detect basic blocks with nothing but a label. This can happen | |
880 | in particular at the end of a function. */ | |
881 | if (b_head == b_end) | |
47bd5598 | 882 | b_empty = true; |
5f0d2358 | 883 | |
ca6c03ca JH |
884 | del_first = del_last = b_head; |
885 | b_head = NEXT_INSN (b_head); | |
886 | } | |
887 | ||
5f0d2358 RK |
888 | /* Delete the basic block note and handle blocks containing just that |
889 | note. */ | |
ca6c03ca JH |
890 | if (NOTE_INSN_BASIC_BLOCK_P (b_head)) |
891 | { | |
892 | if (b_head == b_end) | |
47bd5598 | 893 | b_empty = true; |
ca6c03ca JH |
894 | if (! del_last) |
895 | del_first = b_head; | |
5f0d2358 | 896 | |
ca6c03ca JH |
897 | del_last = b_head; |
898 | b_head = NEXT_INSN (b_head); | |
899 | } | |
900 | ||
901 | /* If there was a jump out of A, delete it. */ | |
4b4bf941 | 902 | if (JUMP_P (a_end)) |
ca6c03ca | 903 | { |
8879d71c | 904 | rtx_insn *prev; |
ca6c03ca JH |
905 | |
906 | for (prev = PREV_INSN (a_end); ; prev = PREV_INSN (prev)) | |
4b4bf941 | 907 | if (!NOTE_P (prev) |
a38e7aa5 | 908 | || NOTE_INSN_BASIC_BLOCK_P (prev) |
a813c111 | 909 | || prev == BB_HEAD (a)) |
ca6c03ca JH |
910 | break; |
911 | ||
912 | del_first = a_end; | |
913 | ||
ca6c03ca JH |
914 | a_end = PREV_INSN (del_first); |
915 | } | |
4b4bf941 | 916 | else if (BARRIER_P (NEXT_INSN (a_end))) |
ca6c03ca JH |
917 | del_first = NEXT_INSN (a_end); |
918 | ||
ca6c03ca JH |
919 | /* Delete everything marked above as well as crap that might be |
920 | hanging out between the two blocks. */ | |
1130d5e3 DM |
921 | BB_END (a) = a_end; |
922 | BB_HEAD (b) = b_empty ? NULL : b_head; | |
a7b87f73 | 923 | delete_insn_chain (del_first, del_last, true); |
ca6c03ca | 924 | |
7792f13c EB |
925 | /* If not optimizing, preserve the locus of the single edge between |
926 | blocks A and B if necessary by emitting a nop. */ | |
927 | if (!optimize | |
928 | && !forward_edge_locus | |
929 | && !DECL_IGNORED_P (current_function_decl)) | |
9be94227 EB |
930 | { |
931 | emit_nop_for_unique_locus_between (a, b); | |
932 | a_end = BB_END (a); | |
933 | } | |
934 | ||
ca6c03ca JH |
935 | /* Reassociate the insns of B with A. */ |
936 | if (!b_empty) | |
937 | { | |
b5b8b0ac | 938 | update_bb_for_insn_chain (a_end, b_debug_end, a); |
5f0d2358 | 939 | |
1130d5e3 DM |
940 | BB_END (a) = b_debug_end; |
941 | BB_HEAD (b) = NULL; | |
b5b8b0ac AO |
942 | } |
943 | else if (b_end != b_debug_end) | |
944 | { | |
945 | /* Move any deleted labels and other notes between the end of A | |
946 | and the debug insns that make up B after the debug insns, | |
947 | bringing the debug insns into A while keeping the notes after | |
948 | the end of A. */ | |
949 | if (NEXT_INSN (a_end) != b_debug_start) | |
950 | reorder_insns_nobb (NEXT_INSN (a_end), PREV_INSN (b_debug_start), | |
951 | b_debug_end); | |
952 | update_bb_for_insn_chain (b_debug_start, b_debug_end, a); | |
1130d5e3 | 953 | BB_END (a) = b_debug_end; |
ca6c03ca | 954 | } |
5f0d2358 | 955 | |
6fb5fa3c | 956 | df_bb_delete (b->index); |
50a36e42 | 957 | |
7792f13c | 958 | if (forward_edge_locus) |
50a36e42 EB |
959 | EDGE_SUCC (b, 0)->goto_locus = EDGE_SUCC (a, 0)->goto_locus; |
960 | ||
961 | if (dump_file) | |
962 | fprintf (dump_file, "Merged blocks %d and %d.\n", a->index, b->index); | |
ca6c03ca | 963 | } |
bc35512f | 964 | |
6fb5fa3c | 965 | |
bc35512f | 966 | /* Return true when block A and B can be merged. */ |
9678086d | 967 | |
b48d0358 DN |
968 | static bool |
969 | rtl_can_merge_blocks (basic_block a, basic_block b) | |
bc35512f | 970 | { |
750054a2 CT |
971 | /* If we are partitioning hot/cold basic blocks, we don't want to |
972 | mess up unconditional or indirect jumps that cross between hot | |
076c7ab8 ZW |
973 | and cold sections. |
974 | ||
8e8d5162 | 975 | Basic block partitioning may result in some jumps that appear to |
c22cacf3 MS |
976 | be optimizable (or blocks that appear to be mergeable), but which really |
977 | must be left untouched (they are required to make it safely across | |
978 | partition boundaries). See the comments at the top of | |
e53b6e56 | 979 | bb-reorder.cc:partition_hot_cold_basic_blocks for complete details. */ |
076c7ab8 | 980 | |
87c8b4be | 981 | if (BB_PARTITION (a) != BB_PARTITION (b)) |
076c7ab8 | 982 | return false; |
750054a2 | 983 | |
7d776ee2 RG |
984 | /* Protect the loop latches. */ |
985 | if (current_loops && b->loop_father->latch == b) | |
986 | return false; | |
987 | ||
bc35512f | 988 | /* There must be exactly one edge in between the blocks. */ |
c5cbcccf ZD |
989 | return (single_succ_p (a) |
990 | && single_succ (a) == b | |
991 | && single_pred_p (b) | |
628f6a4e | 992 | && a != b |
bc35512f | 993 | /* Must be simple edge. */ |
c5cbcccf | 994 | && !(single_succ_edge (a)->flags & EDGE_COMPLEX) |
bc35512f | 995 | && a->next_bb == b |
fefa31b5 DM |
996 | && a != ENTRY_BLOCK_PTR_FOR_FN (cfun) |
997 | && b != EXIT_BLOCK_PTR_FOR_FN (cfun) | |
bc35512f JH |
998 | /* If the jump insn has side effects, |
999 | we can't kill the edge. */ | |
4b4bf941 | 1000 | && (!JUMP_P (BB_END (a)) |
e24e7211 | 1001 | || (reload_completed |
a813c111 | 1002 | ? simplejump_p (BB_END (a)) : onlyjump_p (BB_END (a))))); |
bc35512f | 1003 | } |
ca6c03ca | 1004 | \f |
5f0d2358 RK |
1005 | /* Return the label in the head of basic block BLOCK. Create one if it doesn't |
1006 | exist. */ | |
ca6c03ca | 1007 | |
1476d1bd | 1008 | rtx_code_label * |
d329e058 | 1009 | block_label (basic_block block) |
ca6c03ca | 1010 | { |
fefa31b5 | 1011 | if (block == EXIT_BLOCK_PTR_FOR_FN (cfun)) |
1476d1bd | 1012 | return NULL; |
5f0d2358 | 1013 | |
4b4bf941 | 1014 | if (!LABEL_P (BB_HEAD (block))) |
ca6c03ca | 1015 | { |
1130d5e3 | 1016 | BB_HEAD (block) = emit_label_before (gen_label_rtx (), BB_HEAD (block)); |
ca6c03ca | 1017 | } |
5f0d2358 | 1018 | |
1476d1bd | 1019 | return as_a <rtx_code_label *> (BB_HEAD (block)); |
ca6c03ca JH |
1020 | } |
1021 | ||
91c50487 ML |
1022 | /* Remove all barriers from BB_FOOTER of a BB. */ |
1023 | ||
1024 | static void | |
1025 | remove_barriers_from_footer (basic_block bb) | |
1026 | { | |
1027 | rtx_insn *insn = BB_FOOTER (bb); | |
1028 | ||
1029 | /* Remove barriers but keep jumptables. */ | |
1030 | while (insn) | |
1031 | { | |
1032 | if (BARRIER_P (insn)) | |
1033 | { | |
1034 | if (PREV_INSN (insn)) | |
1035 | SET_NEXT_INSN (PREV_INSN (insn)) = NEXT_INSN (insn); | |
1036 | else | |
1037 | BB_FOOTER (bb) = NEXT_INSN (insn); | |
1038 | if (NEXT_INSN (insn)) | |
1039 | SET_PREV_INSN (NEXT_INSN (insn)) = PREV_INSN (insn); | |
1040 | } | |
1041 | if (LABEL_P (insn)) | |
1042 | return; | |
1043 | insn = NEXT_INSN (insn); | |
1044 | } | |
1045 | } | |
1046 | ||
ca6c03ca | 1047 | /* Attempt to perform edge redirection by replacing possibly complex jump |
5f0d2358 RK |
1048 | instruction by unconditional jump or removing jump completely. This can |
1049 | apply only if all edges now point to the same block. The parameters and | |
1050 | return values are equivalent to redirect_edge_and_branch. */ | |
ca6c03ca | 1051 | |
6de9cd9a | 1052 | edge |
bc35512f | 1053 | try_redirect_by_replacing_jump (edge e, basic_block target, bool in_cfglayout) |
ca6c03ca JH |
1054 | { |
1055 | basic_block src = e->src; | |
bd1cd0d0 | 1056 | rtx_insn *insn = BB_END (src); |
e1233a7d | 1057 | rtx set; |
47bd5598 | 1058 | bool fallthru = false; |
750054a2 CT |
1059 | |
1060 | /* If we are partitioning hot/cold basic blocks, we don't want to | |
1061 | mess up unconditional or indirect jumps that cross between hot | |
8e8d5162 CT |
1062 | and cold sections. |
1063 | ||
1064 | Basic block partitioning may result in some jumps that appear to | |
c22cacf3 MS |
1065 | be optimizable (or blocks that appear to be mergeable), but which really |
1066 | must be left untouched (they are required to make it safely across | |
1067 | partition boundaries). See the comments at the top of | |
e53b6e56 | 1068 | bb-reorder.cc:partition_hot_cold_basic_blocks for complete details. */ |
c22cacf3 | 1069 | |
3371a64f | 1070 | if (BB_PARTITION (src) != BB_PARTITION (target)) |
9cf84a3c | 1071 | return NULL; |
750054a2 | 1072 | |
6a66a8a7 KH |
1073 | /* We can replace or remove a complex jump only when we have exactly |
1074 | two edges. Also, if we have exactly one outgoing edge, we can | |
1075 | redirect that. */ | |
1076 | if (EDGE_COUNT (src->succs) >= 3 | |
1077 | /* Verify that all targets will be TARGET. Specifically, the | |
1078 | edge that is not E must also go to TARGET. */ | |
1079 | || (EDGE_COUNT (src->succs) == 2 | |
1080 | && EDGE_SUCC (src, EDGE_SUCC (src, 0) == e)->dest != target)) | |
1081 | return NULL; | |
5f0d2358 | 1082 | |
6a66a8a7 | 1083 | if (!onlyjump_p (insn)) |
6de9cd9a | 1084 | return NULL; |
3348b696 | 1085 | if ((!optimize || reload_completed) && tablejump_p (insn, NULL, NULL)) |
6de9cd9a | 1086 | return NULL; |
ca6c03ca JH |
1087 | |
1088 | /* Avoid removing branch with side effects. */ | |
1089 | set = single_set (insn); | |
1090 | if (!set || side_effects_p (set)) | |
6de9cd9a | 1091 | return NULL; |
ca6c03ca | 1092 | |
ca6c03ca | 1093 | /* See if we can create the fallthru edge. */ |
bc35512f | 1094 | if (in_cfglayout || can_fallthru (src, target)) |
ca6c03ca | 1095 | { |
c263766c RH |
1096 | if (dump_file) |
1097 | fprintf (dump_file, "Removing jump %i.\n", INSN_UID (insn)); | |
47bd5598 | 1098 | fallthru = true; |
ca6c03ca | 1099 | |
eaec9b3d | 1100 | /* Selectively unlink whole insn chain. */ |
bc35512f JH |
1101 | if (in_cfglayout) |
1102 | { | |
bd1cd0d0 | 1103 | delete_insn_chain (insn, BB_END (src), false); |
91c50487 | 1104 | remove_barriers_from_footer (src); |
bc35512f JH |
1105 | } |
1106 | else | |
bd1cd0d0 | 1107 | delete_insn_chain (insn, PREV_INSN (BB_HEAD (target)), false); |
ca6c03ca | 1108 | } |
5f0d2358 | 1109 | |
ca6c03ca JH |
1110 | /* If this already is simplejump, redirect it. */ |
1111 | else if (simplejump_p (insn)) | |
1112 | { | |
1113 | if (e->dest == target) | |
6de9cd9a | 1114 | return NULL; |
c263766c RH |
1115 | if (dump_file) |
1116 | fprintf (dump_file, "Redirecting jump %i from %i to %i.\n", | |
0b17ab2f | 1117 | INSN_UID (insn), e->dest->index, target->index); |
1476d1bd MM |
1118 | if (!redirect_jump (as_a <rtx_jump_insn *> (insn), |
1119 | block_label (target), 0)) | |
6ee3c8e4 | 1120 | { |
fefa31b5 | 1121 | gcc_assert (target == EXIT_BLOCK_PTR_FOR_FN (cfun)); |
341c100f | 1122 | return NULL; |
6ee3c8e4 | 1123 | } |
ca6c03ca | 1124 | } |
5f0d2358 | 1125 | |
6ee3c8e4 | 1126 | /* Cannot do anything for target exit block. */ |
fefa31b5 | 1127 | else if (target == EXIT_BLOCK_PTR_FOR_FN (cfun)) |
6de9cd9a | 1128 | return NULL; |
6ee3c8e4 | 1129 | |
ca6c03ca JH |
1130 | /* Or replace possibly complicated jump insn by simple jump insn. */ |
1131 | else | |
1132 | { | |
e67d1102 | 1133 | rtx_code_label *target_label = block_label (target); |
8879d71c | 1134 | rtx_insn *barrier; |
dfe08bc4 | 1135 | rtx_insn *label; |
8942ee0f | 1136 | rtx_jump_table_data *table; |
ca6c03ca | 1137 | |
ec4a505f | 1138 | emit_jump_insn_after_noloc (targetm.gen_jump (target_label), insn); |
a813c111 | 1139 | JUMP_LABEL (BB_END (src)) = target_label; |
ca6c03ca | 1140 | LABEL_NUSES (target_label)++; |
c263766c RH |
1141 | if (dump_file) |
1142 | fprintf (dump_file, "Replacing insn %i by jump %i\n", | |
a813c111 | 1143 | INSN_UID (insn), INSN_UID (BB_END (src))); |
ca6c03ca | 1144 | |
4da2eb6b | 1145 | |
bd1cd0d0 | 1146 | delete_insn_chain (insn, insn, false); |
ba4807a0 | 1147 | |
4da2eb6b RH |
1148 | /* Recognize a tablejump that we are converting to a |
1149 | simple jump and remove its associated CODE_LABEL | |
1150 | and ADDR_VEC or ADDR_DIFF_VEC. */ | |
ba4807a0 LB |
1151 | if (tablejump_p (insn, &label, &table)) |
1152 | delete_insn_chain (label, table, false); | |
eb5b8ad4 | 1153 | |
65f4b875 | 1154 | barrier = next_nonnote_nondebug_insn (BB_END (src)); |
4b4bf941 | 1155 | if (!barrier || !BARRIER_P (barrier)) |
a813c111 | 1156 | emit_barrier_after (BB_END (src)); |
5d693491 JZ |
1157 | else |
1158 | { | |
a813c111 | 1159 | if (barrier != NEXT_INSN (BB_END (src))) |
5d693491 JZ |
1160 | { |
1161 | /* Move the jump before barrier so that the notes | |
1162 | which originally were or were created before jump table are | |
1163 | inside the basic block. */ | |
8879d71c | 1164 | rtx_insn *new_insn = BB_END (src); |
5d693491 | 1165 | |
6c3d0e31 SP |
1166 | update_bb_for_insn_chain (NEXT_INSN (BB_END (src)), |
1167 | PREV_INSN (barrier), src); | |
5d693491 | 1168 | |
0f82e5c9 DM |
1169 | SET_NEXT_INSN (PREV_INSN (new_insn)) = NEXT_INSN (new_insn); |
1170 | SET_PREV_INSN (NEXT_INSN (new_insn)) = PREV_INSN (new_insn); | |
5d693491 | 1171 | |
0f82e5c9 DM |
1172 | SET_NEXT_INSN (new_insn) = barrier; |
1173 | SET_NEXT_INSN (PREV_INSN (barrier)) = new_insn; | |
5d693491 | 1174 | |
0f82e5c9 DM |
1175 | SET_PREV_INSN (new_insn) = PREV_INSN (barrier); |
1176 | SET_PREV_INSN (barrier) = new_insn; | |
5d693491 JZ |
1177 | } |
1178 | } | |
ca6c03ca JH |
1179 | } |
1180 | ||
1181 | /* Keep only one edge out and set proper flags. */ | |
c5cbcccf | 1182 | if (!single_succ_p (src)) |
628f6a4e | 1183 | remove_edge (e); |
c5cbcccf | 1184 | gcc_assert (single_succ_p (src)); |
628f6a4e | 1185 | |
c5cbcccf | 1186 | e = single_succ_edge (src); |
ca6c03ca JH |
1187 | if (fallthru) |
1188 | e->flags = EDGE_FALLTHRU; | |
1189 | else | |
1190 | e->flags = 0; | |
5f0d2358 | 1191 | |
357067f2 | 1192 | e->probability = profile_probability::always (); |
ca6c03ca | 1193 | |
ca6c03ca JH |
1194 | if (e->dest != target) |
1195 | redirect_edge_succ (e, target); | |
6de9cd9a | 1196 | return e; |
ca6c03ca JH |
1197 | } |
1198 | ||
4e3825db MM |
1199 | /* Subroutine of redirect_branch_edge that tries to patch the jump |
1200 | instruction INSN so that it reaches block NEW. Do this | |
1201 | only when it originally reached block OLD. Return true if this | |
1202 | worked or the original target wasn't OLD, return false if redirection | |
1203 | doesn't work. */ | |
1204 | ||
1205 | static bool | |
8879d71c | 1206 | patch_jump_insn (rtx_insn *insn, rtx_insn *old_label, basic_block new_bb) |
ca6c03ca | 1207 | { |
8942ee0f | 1208 | rtx_jump_table_data *table; |
ca6c03ca | 1209 | rtx tmp; |
ca6c03ca | 1210 | /* Recognize a tablejump and adjust all matching cases. */ |
8942ee0f | 1211 | if (tablejump_p (insn, NULL, &table)) |
ca6c03ca JH |
1212 | { |
1213 | rtvec vec; | |
1214 | int j; | |
e67d1102 | 1215 | rtx_code_label *new_label = block_label (new_bb); |
ca6c03ca | 1216 | |
fefa31b5 | 1217 | if (new_bb == EXIT_BLOCK_PTR_FOR_FN (cfun)) |
4e3825db | 1218 | return false; |
95c43227 | 1219 | vec = table->get_labels (); |
ca6c03ca JH |
1220 | |
1221 | for (j = GET_NUM_ELEM (vec) - 1; j >= 0; --j) | |
1222 | if (XEXP (RTVEC_ELT (vec, j), 0) == old_label) | |
1223 | { | |
1224 | RTVEC_ELT (vec, j) = gen_rtx_LABEL_REF (Pmode, new_label); | |
1225 | --LABEL_NUSES (old_label); | |
1226 | ++LABEL_NUSES (new_label); | |
1227 | } | |
1228 | ||
f9da5064 | 1229 | /* Handle casesi dispatch insns. */ |
3010ee55 | 1230 | if ((tmp = tablejump_casesi_pattern (insn)) != NULL_RTX |
04a121a7 | 1231 | && label_ref_label (XEXP (SET_SRC (tmp), 2)) == old_label) |
ca6c03ca | 1232 | { |
4c33cb26 | 1233 | XEXP (SET_SRC (tmp), 2) = gen_rtx_LABEL_REF (Pmode, |
ca6c03ca JH |
1234 | new_label); |
1235 | --LABEL_NUSES (old_label); | |
1236 | ++LABEL_NUSES (new_label); | |
1237 | } | |
1238 | } | |
1c384bf1 RH |
1239 | else if ((tmp = extract_asm_operands (PATTERN (insn))) != NULL) |
1240 | { | |
1241 | int i, n = ASM_OPERANDS_LABEL_LENGTH (tmp); | |
e67d1102 | 1242 | rtx note; |
1c384bf1 | 1243 | |
fefa31b5 | 1244 | if (new_bb == EXIT_BLOCK_PTR_FOR_FN (cfun)) |
1c384bf1 | 1245 | return false; |
e67d1102 | 1246 | rtx_code_label *new_label = block_label (new_bb); |
1c384bf1 RH |
1247 | |
1248 | for (i = 0; i < n; ++i) | |
1249 | { | |
1250 | rtx old_ref = ASM_OPERANDS_LABEL (tmp, i); | |
1251 | gcc_assert (GET_CODE (old_ref) == LABEL_REF); | |
1252 | if (XEXP (old_ref, 0) == old_label) | |
1253 | { | |
1254 | ASM_OPERANDS_LABEL (tmp, i) | |
1255 | = gen_rtx_LABEL_REF (Pmode, new_label); | |
1256 | --LABEL_NUSES (old_label); | |
1257 | ++LABEL_NUSES (new_label); | |
1258 | } | |
1259 | } | |
1260 | ||
1261 | if (JUMP_LABEL (insn) == old_label) | |
1262 | { | |
1263 | JUMP_LABEL (insn) = new_label; | |
1264 | note = find_reg_note (insn, REG_LABEL_TARGET, new_label); | |
1265 | if (note) | |
1266 | remove_note (insn, note); | |
1267 | } | |
1268 | else | |
1269 | { | |
1270 | note = find_reg_note (insn, REG_LABEL_TARGET, old_label); | |
1271 | if (note) | |
1272 | remove_note (insn, note); | |
1273 | if (JUMP_LABEL (insn) != new_label | |
1274 | && !find_reg_note (insn, REG_LABEL_TARGET, new_label)) | |
1275 | add_reg_note (insn, REG_LABEL_TARGET, new_label); | |
1276 | } | |
3b5fda81 JJ |
1277 | while ((note = find_reg_note (insn, REG_LABEL_OPERAND, old_label)) |
1278 | != NULL_RTX) | |
1279 | XEXP (note, 0) = new_label; | |
1c384bf1 | 1280 | } |
ca6c03ca JH |
1281 | else |
1282 | { | |
1283 | /* ?? We may play the games with moving the named labels from | |
1284 | one basic block to the other in case only one computed_jump is | |
1285 | available. */ | |
5f0d2358 RK |
1286 | if (computed_jump_p (insn) |
1287 | /* A return instruction can't be redirected. */ | |
1288 | || returnjump_p (insn)) | |
4e3825db | 1289 | return false; |
6ee3c8e4 | 1290 | |
4e3825db | 1291 | if (!currently_expanding_to_rtl || JUMP_LABEL (insn) == old_label) |
6ee3c8e4 | 1292 | { |
4e3825db MM |
1293 | /* If the insn doesn't go where we think, we're confused. */ |
1294 | gcc_assert (JUMP_LABEL (insn) == old_label); | |
1295 | ||
1296 | /* If the substitution doesn't succeed, die. This can happen | |
1297 | if the back end emitted unrecognizable instructions or if | |
a09ad347 JJ |
1298 | target is exit block on some arches. Or for crossing |
1299 | jumps. */ | |
1476d1bd MM |
1300 | if (!redirect_jump (as_a <rtx_jump_insn *> (insn), |
1301 | block_label (new_bb), 0)) | |
4e3825db | 1302 | { |
a09ad347 JJ |
1303 | gcc_assert (new_bb == EXIT_BLOCK_PTR_FOR_FN (cfun) |
1304 | || CROSSING_JUMP_P (insn)); | |
4e3825db MM |
1305 | return false; |
1306 | } | |
6ee3c8e4 | 1307 | } |
ca6c03ca | 1308 | } |
4e3825db MM |
1309 | return true; |
1310 | } | |
1311 | ||
1312 | ||
1313 | /* Redirect edge representing branch of (un)conditional jump or tablejump, | |
1314 | NULL on failure */ | |
1315 | static edge | |
1316 | redirect_branch_edge (edge e, basic_block target) | |
1317 | { | |
8879d71c | 1318 | rtx_insn *old_label = BB_HEAD (e->dest); |
4e3825db | 1319 | basic_block src = e->src; |
8879d71c | 1320 | rtx_insn *insn = BB_END (src); |
4e3825db MM |
1321 | |
1322 | /* We can only redirect non-fallthru edges of jump insn. */ | |
1323 | if (e->flags & EDGE_FALLTHRU) | |
1324 | return NULL; | |
1325 | else if (!JUMP_P (insn) && !currently_expanding_to_rtl) | |
1326 | return NULL; | |
1327 | ||
1328 | if (!currently_expanding_to_rtl) | |
1329 | { | |
1476d1bd | 1330 | if (!patch_jump_insn (as_a <rtx_jump_insn *> (insn), old_label, target)) |
4e3825db MM |
1331 | return NULL; |
1332 | } | |
1333 | else | |
1334 | /* When expanding this BB might actually contain multiple | |
1335 | jumps (i.e. not yet split by find_many_sub_basic_blocks). | |
1336 | Redirect all of those that match our label. */ | |
0f346928 | 1337 | FOR_BB_INSNS (src, insn) |
1476d1bd MM |
1338 | if (JUMP_P (insn) && !patch_jump_insn (as_a <rtx_jump_insn *> (insn), |
1339 | old_label, target)) | |
4e3825db | 1340 | return NULL; |
ca6c03ca | 1341 | |
c263766c RH |
1342 | if (dump_file) |
1343 | fprintf (dump_file, "Edge %i->%i redirected to %i\n", | |
0b17ab2f | 1344 | e->src->index, e->dest->index, target->index); |
5f0d2358 | 1345 | |
ca6c03ca | 1346 | if (e->dest != target) |
6de9cd9a | 1347 | e = redirect_edge_succ_nodup (e, target); |
6fb5fa3c | 1348 | |
6de9cd9a | 1349 | return e; |
bc35512f JH |
1350 | } |
1351 | ||
3371a64f TJ |
1352 | /* Called when edge E has been redirected to a new destination, |
1353 | in order to update the region crossing flag on the edge and | |
1354 | jump. */ | |
1355 | ||
1356 | static void | |
1357 | fixup_partition_crossing (edge e) | |
1358 | { | |
fefa31b5 DM |
1359 | if (e->src == ENTRY_BLOCK_PTR_FOR_FN (cfun) || e->dest |
1360 | == EXIT_BLOCK_PTR_FOR_FN (cfun)) | |
3371a64f TJ |
1361 | return; |
1362 | /* If we redirected an existing edge, it may already be marked | |
1363 | crossing, even though the new src is missing a reg crossing note. | |
1364 | But make sure reg crossing note doesn't already exist before | |
1365 | inserting. */ | |
1366 | if (BB_PARTITION (e->src) != BB_PARTITION (e->dest)) | |
1367 | { | |
1368 | e->flags |= EDGE_CROSSING; | |
52af3804 | 1369 | if (JUMP_P (BB_END (e->src))) |
339ba33b | 1370 | CROSSING_JUMP_P (BB_END (e->src)) = 1; |
3371a64f TJ |
1371 | } |
1372 | else if (BB_PARTITION (e->src) == BB_PARTITION (e->dest)) | |
1373 | { | |
1374 | e->flags &= ~EDGE_CROSSING; | |
1375 | /* Remove the section crossing note from jump at end of | |
1376 | src if it exists, and if no other successors are | |
1377 | still crossing. */ | |
339ba33b | 1378 | if (JUMP_P (BB_END (e->src)) && CROSSING_JUMP_P (BB_END (e->src))) |
3371a64f TJ |
1379 | { |
1380 | bool has_crossing_succ = false; | |
1381 | edge e2; | |
1382 | edge_iterator ei; | |
1383 | FOR_EACH_EDGE (e2, ei, e->src->succs) | |
1384 | { | |
1385 | has_crossing_succ |= (e2->flags & EDGE_CROSSING); | |
1386 | if (has_crossing_succ) | |
1387 | break; | |
1388 | } | |
1389 | if (!has_crossing_succ) | |
339ba33b | 1390 | CROSSING_JUMP_P (BB_END (e->src)) = 0; |
3371a64f TJ |
1391 | } |
1392 | } | |
1393 | } | |
1394 | ||
600b5b1d TJ |
1395 | /* Called when block BB has been reassigned to the cold partition, |
1396 | because it is now dominated by another cold block, | |
1397 | to ensure that the region crossing attributes are updated. */ | |
1398 | ||
1399 | static void | |
1400 | fixup_new_cold_bb (basic_block bb) | |
1401 | { | |
1402 | edge e; | |
1403 | edge_iterator ei; | |
1404 | ||
1405 | /* This is called when a hot bb is found to now be dominated | |
1406 | by a cold bb and therefore needs to become cold. Therefore, | |
1407 | its preds will no longer be region crossing. Any non-dominating | |
1408 | preds that were previously hot would also have become cold | |
1409 | in the caller for the same region. Any preds that were previously | |
1410 | region-crossing will be adjusted in fixup_partition_crossing. */ | |
1411 | FOR_EACH_EDGE (e, ei, bb->preds) | |
1412 | { | |
1413 | fixup_partition_crossing (e); | |
1414 | } | |
1415 | ||
1416 | /* Possibly need to make bb's successor edges region crossing, | |
1417 | or remove stale region crossing. */ | |
1418 | FOR_EACH_EDGE (e, ei, bb->succs) | |
1419 | { | |
1420 | /* We can't have fall-through edges across partition boundaries. | |
1421 | Note that force_nonfallthru will do any necessary partition | |
1422 | boundary fixup by calling fixup_partition_crossing itself. */ | |
1423 | if ((e->flags & EDGE_FALLTHRU) | |
1424 | && BB_PARTITION (bb) != BB_PARTITION (e->dest) | |
fefa31b5 | 1425 | && e->dest != EXIT_BLOCK_PTR_FOR_FN (cfun)) |
600b5b1d TJ |
1426 | force_nonfallthru (e); |
1427 | else | |
1428 | fixup_partition_crossing (e); | |
1429 | } | |
1430 | } | |
1431 | ||
bc35512f JH |
1432 | /* Attempt to change code to redirect edge E to TARGET. Don't do that on |
1433 | expense of adding new instructions or reordering basic blocks. | |
1434 | ||
1435 | Function can be also called with edge destination equivalent to the TARGET. | |
1436 | Then it should try the simplifications and do nothing if none is possible. | |
1437 | ||
6de9cd9a DN |
1438 | Return edge representing the branch if transformation succeeded. Return NULL |
1439 | on failure. | |
1440 | We still return NULL in case E already destinated TARGET and we didn't | |
1441 | managed to simplify instruction stream. */ | |
bc35512f | 1442 | |
6de9cd9a | 1443 | static edge |
5671bf27 | 1444 | rtl_redirect_edge_and_branch (edge e, basic_block target) |
bc35512f | 1445 | { |
6de9cd9a | 1446 | edge ret; |
f345f21a | 1447 | basic_block src = e->src; |
3371a64f | 1448 | basic_block dest = e->dest; |
f345f21a | 1449 | |
bc35512f | 1450 | if (e->flags & (EDGE_ABNORMAL_CALL | EDGE_EH)) |
6de9cd9a | 1451 | return NULL; |
bc35512f | 1452 | |
3371a64f | 1453 | if (dest == target) |
6de9cd9a | 1454 | return e; |
3348b696 | 1455 | |
6de9cd9a | 1456 | if ((ret = try_redirect_by_replacing_jump (e, target, false)) != NULL) |
f345f21a | 1457 | { |
6fb5fa3c | 1458 | df_set_bb_dirty (src); |
3371a64f | 1459 | fixup_partition_crossing (ret); |
6de9cd9a | 1460 | return ret; |
f345f21a | 1461 | } |
bc35512f | 1462 | |
6de9cd9a DN |
1463 | ret = redirect_branch_edge (e, target); |
1464 | if (!ret) | |
1465 | return NULL; | |
5f0d2358 | 1466 | |
6fb5fa3c | 1467 | df_set_bb_dirty (src); |
3371a64f | 1468 | fixup_partition_crossing (ret); |
6de9cd9a | 1469 | return ret; |
ca6c03ca JH |
1470 | } |
1471 | ||
3371a64f TJ |
1472 | /* Emit a barrier after BB, into the footer if we are in CFGLAYOUT mode. */ |
1473 | ||
1474 | void | |
1475 | emit_barrier_after_bb (basic_block bb) | |
1476 | { | |
cd459bf8 | 1477 | rtx_barrier *barrier = emit_barrier_after (BB_END (bb)); |
c3284718 | 1478 | gcc_assert (current_ir_type () == IR_RTL_CFGRTL |
3371a64f TJ |
1479 | || current_ir_type () == IR_RTL_CFGLAYOUT); |
1480 | if (current_ir_type () == IR_RTL_CFGLAYOUT) | |
0fb3402f RX |
1481 | { |
1482 | rtx_insn *insn = unlink_insn_chain (barrier, barrier); | |
1483 | ||
1484 | if (BB_FOOTER (bb)) | |
1485 | { | |
1486 | rtx_insn *footer_tail = BB_FOOTER (bb); | |
1487 | ||
1488 | while (NEXT_INSN (footer_tail)) | |
1489 | footer_tail = NEXT_INSN (footer_tail); | |
1490 | if (!BARRIER_P (footer_tail)) | |
1491 | { | |
1492 | SET_NEXT_INSN (footer_tail) = insn; | |
1493 | SET_PREV_INSN (insn) = footer_tail; | |
1494 | } | |
1495 | } | |
1496 | else | |
1497 | BB_FOOTER (bb) = insn; | |
1498 | } | |
3371a64f TJ |
1499 | } |
1500 | ||
4fe9b91c | 1501 | /* Like force_nonfallthru below, but additionally performs redirection |
26898771 BS |
1502 | Used by redirect_edge_and_branch_force. JUMP_LABEL is used only |
1503 | when redirecting to the EXIT_BLOCK, it is either ret_rtx or | |
1504 | simple_return_rtx, indicating which kind of returnjump to create. | |
1505 | It should be NULL otherwise. */ | |
ca6c03ca | 1506 | |
dc0ff1c8 | 1507 | basic_block |
26898771 | 1508 | force_nonfallthru_and_redirect (edge e, basic_block target, rtx jump_label) |
ca6c03ca | 1509 | { |
a3716585 | 1510 | basic_block jump_block, new_bb = NULL, src = e->src; |
ca6c03ca JH |
1511 | rtx note; |
1512 | edge new_edge; | |
a3716585 | 1513 | int abnormal_edge_flags = 0; |
a3e6a37b | 1514 | bool asm_goto_edge = false; |
7241571e | 1515 | int loc; |
ca6c03ca | 1516 | |
cb9a1d9b JH |
1517 | /* In the case the last instruction is conditional jump to the next |
1518 | instruction, first redirect the jump itself and then continue | |
b20b352b | 1519 | by creating a basic block afterwards to redirect fallthru edge. */ |
fefa31b5 DM |
1520 | if (e->src != ENTRY_BLOCK_PTR_FOR_FN (cfun) |
1521 | && e->dest != EXIT_BLOCK_PTR_FOR_FN (cfun) | |
a813c111 | 1522 | && any_condjump_p (BB_END (e->src)) |
a813c111 | 1523 | && JUMP_LABEL (BB_END (e->src)) == BB_HEAD (e->dest)) |
cb9a1d9b JH |
1524 | { |
1525 | rtx note; | |
58e6ae30 | 1526 | edge b = unchecked_make_edge (e->src, target, 0); |
341c100f | 1527 | bool redirected; |
cb9a1d9b | 1528 | |
1476d1bd MM |
1529 | redirected = redirect_jump (as_a <rtx_jump_insn *> (BB_END (e->src)), |
1530 | block_label (target), 0); | |
341c100f | 1531 | gcc_assert (redirected); |
c22cacf3 | 1532 | |
a813c111 | 1533 | note = find_reg_note (BB_END (e->src), REG_BR_PROB, NULL_RTX); |
cb9a1d9b JH |
1534 | if (note) |
1535 | { | |
e5af9ddd | 1536 | int prob = XINT (note, 0); |
cb9a1d9b | 1537 | |
5fa396ad | 1538 | b->probability = profile_probability::from_reg_br_prob_note (prob); |
cb9a1d9b | 1539 | e->probability -= e->probability; |
cb9a1d9b JH |
1540 | } |
1541 | } | |
1542 | ||
ca6c03ca | 1543 | if (e->flags & EDGE_ABNORMAL) |
a3716585 JH |
1544 | { |
1545 | /* Irritating special case - fallthru edge to the same block as abnormal | |
1546 | edge. | |
1547 | We can't redirect abnormal edge, but we still can split the fallthru | |
d329e058 | 1548 | one and create separate abnormal edge to original destination. |
a3716585 | 1549 | This allows bb-reorder to make such edge non-fallthru. */ |
341c100f | 1550 | gcc_assert (e->dest == target); |
ee44c28d SB |
1551 | abnormal_edge_flags = e->flags & ~EDGE_FALLTHRU; |
1552 | e->flags &= EDGE_FALLTHRU; | |
a3716585 | 1553 | } |
341c100f | 1554 | else |
24c545ff | 1555 | { |
341c100f | 1556 | gcc_assert (e->flags & EDGE_FALLTHRU); |
fefa31b5 | 1557 | if (e->src == ENTRY_BLOCK_PTR_FOR_FN (cfun)) |
341c100f NS |
1558 | { |
1559 | /* We can't redirect the entry block. Create an empty block | |
628f6a4e BE |
1560 | at the start of the function which we use to add the new |
1561 | jump. */ | |
1562 | edge tmp; | |
1563 | edge_iterator ei; | |
1564 | bool found = false; | |
c22cacf3 | 1565 | |
fefa31b5 DM |
1566 | basic_block bb = create_basic_block (BB_HEAD (e->dest), NULL, |
1567 | ENTRY_BLOCK_PTR_FOR_FN (cfun)); | |
e7a74006 | 1568 | bb->count = ENTRY_BLOCK_PTR_FOR_FN (cfun)->count; |
c22cacf3 | 1569 | |
63e1159c JJ |
1570 | /* Make sure new block ends up in correct hot/cold section. */ |
1571 | BB_COPY_PARTITION (bb, e->dest); | |
1572 | ||
341c100f NS |
1573 | /* Change the existing edge's source to be the new block, and add |
1574 | a new edge from the entry block to the new block. */ | |
1575 | e->src = bb; | |
fefa31b5 DM |
1576 | for (ei = ei_start (ENTRY_BLOCK_PTR_FOR_FN (cfun)->succs); |
1577 | (tmp = ei_safe_edge (ei)); ) | |
628f6a4e BE |
1578 | { |
1579 | if (tmp == e) | |
1580 | { | |
fefa31b5 | 1581 | ENTRY_BLOCK_PTR_FOR_FN (cfun)->succs->unordered_remove (ei.index); |
628f6a4e BE |
1582 | found = true; |
1583 | break; | |
1584 | } | |
1585 | else | |
1586 | ei_next (&ei); | |
1587 | } | |
c22cacf3 | 1588 | |
628f6a4e | 1589 | gcc_assert (found); |
c22cacf3 | 1590 | |
9771b263 | 1591 | vec_safe_push (bb->succs, e); |
fefa31b5 DM |
1592 | make_single_succ_edge (ENTRY_BLOCK_PTR_FOR_FN (cfun), bb, |
1593 | EDGE_FALLTHRU); | |
341c100f | 1594 | } |
24c545ff BS |
1595 | } |
1596 | ||
a3e6a37b | 1597 | /* If e->src ends with asm goto, see if any of the ASM_OPERANDS_LABELs |
891ca07d | 1598 | don't point to the target or fallthru label. */ |
a3e6a37b | 1599 | if (JUMP_P (BB_END (e->src)) |
fefa31b5 | 1600 | && target != EXIT_BLOCK_PTR_FOR_FN (cfun) |
a3e6a37b JJ |
1601 | && (e->flags & EDGE_FALLTHRU) |
1602 | && (note = extract_asm_operands (PATTERN (BB_END (e->src))))) | |
ca6c03ca | 1603 | { |
a3e6a37b | 1604 | int i, n = ASM_OPERANDS_LABEL_LENGTH (note); |
5d68b7e6 | 1605 | bool adjust_jump_target = false; |
a3e6a37b JJ |
1606 | |
1607 | for (i = 0; i < n; ++i) | |
891ca07d JJ |
1608 | { |
1609 | if (XEXP (ASM_OPERANDS_LABEL (note, i), 0) == BB_HEAD (e->dest)) | |
5d68b7e6 JJ |
1610 | { |
1611 | LABEL_NUSES (XEXP (ASM_OPERANDS_LABEL (note, i), 0))--; | |
1612 | XEXP (ASM_OPERANDS_LABEL (note, i), 0) = block_label (target); | |
1613 | LABEL_NUSES (XEXP (ASM_OPERANDS_LABEL (note, i), 0))++; | |
1614 | adjust_jump_target = true; | |
1615 | } | |
891ca07d | 1616 | if (XEXP (ASM_OPERANDS_LABEL (note, i), 0) == BB_HEAD (target)) |
a3e6a37b | 1617 | asm_goto_edge = true; |
891ca07d | 1618 | } |
5d68b7e6 JJ |
1619 | if (adjust_jump_target) |
1620 | { | |
8879d71c DM |
1621 | rtx_insn *insn = BB_END (e->src); |
1622 | rtx note; | |
1623 | rtx_insn *old_label = BB_HEAD (e->dest); | |
1624 | rtx_insn *new_label = BB_HEAD (target); | |
5d68b7e6 JJ |
1625 | |
1626 | if (JUMP_LABEL (insn) == old_label) | |
1627 | { | |
1628 | JUMP_LABEL (insn) = new_label; | |
1629 | note = find_reg_note (insn, REG_LABEL_TARGET, new_label); | |
1630 | if (note) | |
1631 | remove_note (insn, note); | |
1632 | } | |
1633 | else | |
1634 | { | |
1635 | note = find_reg_note (insn, REG_LABEL_TARGET, old_label); | |
1636 | if (note) | |
1637 | remove_note (insn, note); | |
1638 | if (JUMP_LABEL (insn) != new_label | |
1639 | && !find_reg_note (insn, REG_LABEL_TARGET, new_label)) | |
1640 | add_reg_note (insn, REG_LABEL_TARGET, new_label); | |
1641 | } | |
1642 | while ((note = find_reg_note (insn, REG_LABEL_OPERAND, old_label)) | |
1643 | != NULL_RTX) | |
1644 | XEXP (note, 0) = new_label; | |
1645 | } | |
a3e6a37b JJ |
1646 | } |
1647 | ||
1648 | if (EDGE_COUNT (e->src->succs) >= 2 || abnormal_edge_flags || asm_goto_edge) | |
1649 | { | |
dc01c3d1 | 1650 | rtx_insn *new_head; |
ef30ab83 | 1651 | profile_count count = e->count (); |
357067f2 | 1652 | profile_probability probability = e->probability; |
ca6c03ca | 1653 | /* Create the new structures. */ |
31a78298 | 1654 | |
79019985 RH |
1655 | /* If the old block ended with a tablejump, skip its table |
1656 | by searching forward from there. Otherwise start searching | |
1657 | forward from the last instruction of the old block. */ | |
8942ee0f DM |
1658 | rtx_jump_table_data *table; |
1659 | if (tablejump_p (BB_END (e->src), NULL, &table)) | |
dc01c3d1 | 1660 | new_head = table; |
8942ee0f | 1661 | else |
dc01c3d1 DM |
1662 | new_head = BB_END (e->src); |
1663 | new_head = NEXT_INSN (new_head); | |
31a78298 | 1664 | |
dc01c3d1 | 1665 | jump_block = create_basic_block (new_head, NULL, e->src); |
a3e6a37b | 1666 | jump_block->count = count; |
ca6c03ca | 1667 | |
750054a2 CT |
1668 | /* Make sure new block ends up in correct hot/cold section. */ |
1669 | ||
076c7ab8 | 1670 | BB_COPY_PARTITION (jump_block, e->src); |
c22cacf3 | 1671 | |
ca6c03ca JH |
1672 | /* Wire edge in. */ |
1673 | new_edge = make_edge (e->src, jump_block, EDGE_FALLTHRU); | |
a3e6a37b | 1674 | new_edge->probability = probability; |
ca6c03ca JH |
1675 | |
1676 | /* Redirect old edge. */ | |
1677 | redirect_edge_pred (e, jump_block); | |
357067f2 | 1678 | e->probability = profile_probability::always (); |
ca6c03ca | 1679 | |
3371a64f TJ |
1680 | /* If e->src was previously region crossing, it no longer is |
1681 | and the reg crossing note should be removed. */ | |
1682 | fixup_partition_crossing (new_edge); | |
1683 | ||
a3e6a37b JJ |
1684 | /* If asm goto has any label refs to target's label, |
1685 | add also edge from asm goto bb to target. */ | |
1686 | if (asm_goto_edge) | |
1687 | { | |
9f55aee9 ML |
1688 | new_edge->probability /= 2; |
1689 | jump_block->count /= 2; | |
3995f3a2 JH |
1690 | edge new_edge2 = make_edge (new_edge->src, target, |
1691 | e->flags & ~EDGE_FALLTHRU); | |
1692 | new_edge2->probability = probability - new_edge->probability; | |
a3e6a37b JJ |
1693 | } |
1694 | ||
ca6c03ca JH |
1695 | new_bb = jump_block; |
1696 | } | |
1697 | else | |
1698 | jump_block = e->src; | |
5f0d2358 | 1699 | |
2f13f2de | 1700 | loc = e->goto_locus; |
ca6c03ca | 1701 | e->flags &= ~EDGE_FALLTHRU; |
fefa31b5 | 1702 | if (target == EXIT_BLOCK_PTR_FOR_FN (cfun)) |
ca6c03ca | 1703 | { |
26898771 | 1704 | if (jump_label == ret_rtx) |
4bccb39e RS |
1705 | emit_jump_insn_after_setloc (targetm.gen_return (), |
1706 | BB_END (jump_block), loc); | |
26898771 BS |
1707 | else |
1708 | { | |
1709 | gcc_assert (jump_label == simple_return_rtx); | |
4bccb39e | 1710 | emit_jump_insn_after_setloc (targetm.gen_simple_return (), |
26898771 | 1711 | BB_END (jump_block), loc); |
26898771 | 1712 | } |
387748de | 1713 | set_return_jump_label (BB_END (jump_block)); |
ca6c03ca JH |
1714 | } |
1715 | else | |
1716 | { | |
e67d1102 | 1717 | rtx_code_label *label = block_label (target); |
ec4a505f RS |
1718 | emit_jump_insn_after_setloc (targetm.gen_jump (label), |
1719 | BB_END (jump_block), loc); | |
a813c111 | 1720 | JUMP_LABEL (BB_END (jump_block)) = label; |
ca6c03ca JH |
1721 | LABEL_NUSES (label)++; |
1722 | } | |
5f0d2358 | 1723 | |
3371a64f TJ |
1724 | /* We might be in cfg layout mode, and if so, the following routine will |
1725 | insert the barrier correctly. */ | |
1726 | emit_barrier_after_bb (jump_block); | |
ca6c03ca JH |
1727 | redirect_edge_succ_nodup (e, target); |
1728 | ||
a3716585 JH |
1729 | if (abnormal_edge_flags) |
1730 | make_edge (src, target, abnormal_edge_flags); | |
1731 | ||
b8698a0f | 1732 | df_mark_solutions_dirty (); |
3371a64f | 1733 | fixup_partition_crossing (e); |
ca6c03ca JH |
1734 | return new_bb; |
1735 | } | |
1736 | ||
1737 | /* Edge E is assumed to be fallthru edge. Emit needed jump instruction | |
1738 | (and possibly create new basic block) to make edge non-fallthru. | |
1739 | Return newly created BB or NULL if none. */ | |
5f0d2358 | 1740 | |
cf103ca4 EB |
1741 | static basic_block |
1742 | rtl_force_nonfallthru (edge e) | |
ca6c03ca | 1743 | { |
26898771 | 1744 | return force_nonfallthru_and_redirect (e, e->dest, NULL_RTX); |
ca6c03ca JH |
1745 | } |
1746 | ||
1747 | /* Redirect edge even at the expense of creating new jump insn or | |
1748 | basic block. Return new basic block if created, NULL otherwise. | |
41806d92 | 1749 | Conversion must be possible. */ |
ca6c03ca | 1750 | |
9ee634e3 | 1751 | static basic_block |
d329e058 | 1752 | rtl_redirect_edge_and_branch_force (edge e, basic_block target) |
ca6c03ca | 1753 | { |
5f0d2358 RK |
1754 | if (redirect_edge_and_branch (e, target) |
1755 | || e->dest == target) | |
ca6c03ca JH |
1756 | return NULL; |
1757 | ||
1758 | /* In case the edge redirection failed, try to force it to be non-fallthru | |
1759 | and redirect newly created simplejump. */ | |
6fb5fa3c | 1760 | df_set_bb_dirty (e->src); |
26898771 | 1761 | return force_nonfallthru_and_redirect (e, target, NULL_RTX); |
ca6c03ca JH |
1762 | } |
1763 | ||
1764 | /* The given edge should potentially be a fallthru edge. If that is in | |
1765 | fact true, delete the jump and barriers that are in the way. */ | |
1766 | ||
f470c378 ZD |
1767 | static void |
1768 | rtl_tidy_fallthru_edge (edge e) | |
ca6c03ca | 1769 | { |
8879d71c | 1770 | rtx_insn *q; |
f470c378 ZD |
1771 | basic_block b = e->src, c = b->next_bb; |
1772 | ||
ca6c03ca JH |
1773 | /* ??? In a late-running flow pass, other folks may have deleted basic |
1774 | blocks by nopping out blocks, leaving multiple BARRIERs between here | |
0fa2e4df | 1775 | and the target label. They ought to be chastised and fixed. |
ca6c03ca JH |
1776 | |
1777 | We can also wind up with a sequence of undeletable labels between | |
1778 | one block and the next. | |
1779 | ||
1780 | So search through a sequence of barriers, labels, and notes for | |
1781 | the head of block C and assert that we really do fall through. */ | |
1782 | ||
a813c111 | 1783 | for (q = NEXT_INSN (BB_END (b)); q != BB_HEAD (c); q = NEXT_INSN (q)) |
65f4b875 | 1784 | if (NONDEBUG_INSN_P (q)) |
9c0a0632 | 1785 | return; |
ca6c03ca JH |
1786 | |
1787 | /* Remove what will soon cease being the jump insn from the source block. | |
1788 | If block B consisted only of this single jump, turn it into a deleted | |
1789 | note. */ | |
a813c111 | 1790 | q = BB_END (b); |
4b4bf941 | 1791 | if (JUMP_P (q) |
ca6c03ca JH |
1792 | && onlyjump_p (q) |
1793 | && (any_uncondjump_p (q) | |
c5cbcccf | 1794 | || single_succ_p (b))) |
ca6c03ca | 1795 | { |
dfe08bc4 | 1796 | rtx_insn *label; |
adfac8df JJ |
1797 | rtx_jump_table_data *table; |
1798 | ||
1799 | if (tablejump_p (q, &label, &table)) | |
1800 | { | |
1801 | /* The label is likely mentioned in some instruction before | |
1802 | the tablejump and might not be DCEd, so turn it into | |
1803 | a note instead and move before the tablejump that is going to | |
1804 | be deleted. */ | |
1805 | const char *name = LABEL_NAME (label); | |
1806 | PUT_CODE (label, NOTE); | |
1807 | NOTE_KIND (label) = NOTE_INSN_DELETED_LABEL; | |
1808 | NOTE_DELETED_LABEL_NAME (label) = name; | |
dfe08bc4 | 1809 | reorder_insns (label, label, PREV_INSN (q)); |
adfac8df JJ |
1810 | delete_insn (table); |
1811 | } | |
1812 | ||
ca6c03ca | 1813 | q = PREV_INSN (q); |
ca6c03ca | 1814 | } |
b34f29a1 JJ |
1815 | /* Unconditional jumps with side-effects (i.e. which we can't just delete |
1816 | together with the barrier) should never have a fallthru edge. */ | |
1817 | else if (JUMP_P (q) && any_uncondjump_p (q)) | |
1818 | return; | |
ca6c03ca JH |
1819 | |
1820 | /* Selectively unlink the sequence. */ | |
a813c111 | 1821 | if (q != PREV_INSN (BB_HEAD (c))) |
a7b87f73 | 1822 | delete_insn_chain (NEXT_INSN (q), PREV_INSN (BB_HEAD (c)), false); |
ca6c03ca JH |
1823 | |
1824 | e->flags |= EDGE_FALLTHRU; | |
1825 | } | |
ca6c03ca | 1826 | \f |
f470c378 ZD |
1827 | /* Should move basic block BB after basic block AFTER. NIY. */ |
1828 | ||
1829 | static bool | |
1830 | rtl_move_block_after (basic_block bb ATTRIBUTE_UNUSED, | |
1831 | basic_block after ATTRIBUTE_UNUSED) | |
1832 | { | |
1833 | return false; | |
1834 | } | |
1835 | ||
3371a64f TJ |
1836 | /* Locate the last bb in the same partition as START_BB. */ |
1837 | ||
1838 | static basic_block | |
1839 | last_bb_in_partition (basic_block start_bb) | |
1840 | { | |
1841 | basic_block bb; | |
fefa31b5 | 1842 | FOR_BB_BETWEEN (bb, start_bb, EXIT_BLOCK_PTR_FOR_FN (cfun), next_bb) |
3371a64f TJ |
1843 | { |
1844 | if (BB_PARTITION (start_bb) != BB_PARTITION (bb->next_bb)) | |
1845 | return bb; | |
1846 | } | |
6626665f | 1847 | /* Return bb before the exit block. */ |
3371a64f TJ |
1848 | return bb->prev_bb; |
1849 | } | |
1850 | ||
ca6c03ca | 1851 | /* Split a (typically critical) edge. Return the new block. |
41806d92 | 1852 | The edge must not be abnormal. |
ca6c03ca JH |
1853 | |
1854 | ??? The code generally expects to be called on critical edges. | |
1855 | The case of a block ending in an unconditional jump to a | |
1856 | block with multiple predecessors is not handled optimally. */ | |
1857 | ||
8ce33230 | 1858 | static basic_block |
d329e058 | 1859 | rtl_split_edge (edge edge_in) |
ca6c03ca | 1860 | { |
3371a64f | 1861 | basic_block bb, new_bb; |
8879d71c | 1862 | rtx_insn *before; |
ca6c03ca JH |
1863 | |
1864 | /* Abnormal edges cannot be split. */ | |
341c100f | 1865 | gcc_assert (!(edge_in->flags & EDGE_ABNORMAL)); |
ca6c03ca JH |
1866 | |
1867 | /* We are going to place the new block in front of edge destination. | |
eaec9b3d | 1868 | Avoid existence of fallthru predecessors. */ |
ca6c03ca JH |
1869 | if ((edge_in->flags & EDGE_FALLTHRU) == 0) |
1870 | { | |
0fd4b31d | 1871 | edge e = find_fallthru_edge (edge_in->dest->preds); |
ca6c03ca JH |
1872 | |
1873 | if (e) | |
1874 | force_nonfallthru (e); | |
1875 | } | |
1876 | ||
96e82e0a | 1877 | /* Create the basic block note. */ |
fefa31b5 | 1878 | if (edge_in->dest != EXIT_BLOCK_PTR_FOR_FN (cfun)) |
a813c111 | 1879 | before = BB_HEAD (edge_in->dest); |
ca6c03ca | 1880 | else |
8879d71c | 1881 | before = NULL; |
ca6c03ca | 1882 | |
623a66fa | 1883 | /* If this is a fall through edge to the exit block, the blocks might be |
ffe14686 | 1884 | not adjacent, and the right place is after the source. */ |
fefa31b5 DM |
1885 | if ((edge_in->flags & EDGE_FALLTHRU) |
1886 | && edge_in->dest == EXIT_BLOCK_PTR_FOR_FN (cfun)) | |
623a66fa R |
1887 | { |
1888 | before = NEXT_INSN (BB_END (edge_in->src)); | |
623a66fa | 1889 | bb = create_basic_block (before, NULL, edge_in->src); |
076c7ab8 | 1890 | BB_COPY_PARTITION (bb, edge_in->src); |
623a66fa R |
1891 | } |
1892 | else | |
9fb32434 | 1893 | { |
fefa31b5 | 1894 | if (edge_in->src == ENTRY_BLOCK_PTR_FOR_FN (cfun)) |
3371a64f TJ |
1895 | { |
1896 | bb = create_basic_block (before, NULL, edge_in->dest->prev_bb); | |
1897 | BB_COPY_PARTITION (bb, edge_in->dest); | |
1898 | } | |
1899 | else | |
1900 | { | |
1901 | basic_block after = edge_in->dest->prev_bb; | |
1902 | /* If this is post-bb reordering, and the edge crosses a partition | |
1903 | boundary, the new block needs to be inserted in the bb chain | |
1904 | at the end of the src partition (since we put the new bb into | |
1905 | that partition, see below). Otherwise we may end up creating | |
1906 | an extra partition crossing in the chain, which is illegal. | |
1907 | It can't go after the src, because src may have a fall-through | |
1908 | to a different block. */ | |
1909 | if (crtl->bb_reorder_complete | |
1910 | && (edge_in->flags & EDGE_CROSSING)) | |
1911 | { | |
1912 | after = last_bb_in_partition (edge_in->src); | |
b3a3ae09 | 1913 | before = get_last_bb_insn (after); |
3371a64f TJ |
1914 | /* The instruction following the last bb in partition should |
1915 | be a barrier, since it cannot end in a fall-through. */ | |
1916 | gcc_checking_assert (BARRIER_P (before)); | |
1917 | before = NEXT_INSN (before); | |
1918 | } | |
1919 | bb = create_basic_block (before, NULL, after); | |
1920 | /* Put the split bb into the src partition, to avoid creating | |
1921 | a situation where a cold bb dominates a hot bb, in the case | |
1922 | where src is cold and dest is hot. The src will dominate | |
1923 | the new bb (whereas it might not have dominated dest). */ | |
1924 | BB_COPY_PARTITION (bb, edge_in->src); | |
1925 | } | |
9fb32434 | 1926 | } |
ca6c03ca | 1927 | |
4977bab6 | 1928 | make_single_succ_edge (bb, edge_in->dest, EDGE_FALLTHRU); |
ca6c03ca | 1929 | |
3371a64f TJ |
1930 | /* Can't allow a region crossing edge to be fallthrough. */ |
1931 | if (BB_PARTITION (bb) != BB_PARTITION (edge_in->dest) | |
fefa31b5 | 1932 | && edge_in->dest != EXIT_BLOCK_PTR_FOR_FN (cfun)) |
3371a64f TJ |
1933 | { |
1934 | new_bb = force_nonfallthru (single_succ_edge (bb)); | |
1935 | gcc_assert (!new_bb); | |
1936 | } | |
1937 | ||
4d6922ee | 1938 | /* For non-fallthru edges, we must adjust the predecessor's |
ca6c03ca JH |
1939 | jump instruction to target our new block. */ |
1940 | if ((edge_in->flags & EDGE_FALLTHRU) == 0) | |
1941 | { | |
341c100f NS |
1942 | edge redirected = redirect_edge_and_branch (edge_in, bb); |
1943 | gcc_assert (redirected); | |
ca6c03ca JH |
1944 | } |
1945 | else | |
3b5fda81 | 1946 | { |
fefa31b5 | 1947 | if (edge_in->src != ENTRY_BLOCK_PTR_FOR_FN (cfun)) |
3b5fda81 JJ |
1948 | { |
1949 | /* For asm goto even splitting of fallthru edge might | |
1950 | need insn patching, as other labels might point to the | |
1951 | old label. */ | |
8879d71c | 1952 | rtx_insn *last = BB_END (edge_in->src); |
3b5fda81 JJ |
1953 | if (last |
1954 | && JUMP_P (last) | |
fefa31b5 | 1955 | && edge_in->dest != EXIT_BLOCK_PTR_FOR_FN (cfun) |
81e63b63 SB |
1956 | && (extract_asm_operands (PATTERN (last)) |
1957 | || JUMP_LABEL (last) == before) | |
3b5fda81 JJ |
1958 | && patch_jump_insn (last, before, bb)) |
1959 | df_set_bb_dirty (edge_in->src); | |
1960 | } | |
1961 | redirect_edge_succ (edge_in, bb); | |
1962 | } | |
ca6c03ca JH |
1963 | |
1964 | return bb; | |
1965 | } | |
1966 | ||
1967 | /* Queue instructions for insertion on an edge between two basic blocks. | |
1968 | The new instructions and basic blocks (if any) will not appear in the | |
2b4efc5d JJ |
1969 | CFG until commit_edge_insertions is called. If there are already |
1970 | queued instructions on the edge, PATTERN is appended to them. */ | |
ca6c03ca JH |
1971 | |
1972 | void | |
d329e058 | 1973 | insert_insn_on_edge (rtx pattern, edge e) |
ca6c03ca JH |
1974 | { |
1975 | /* We cannot insert instructions on an abnormal critical edge. | |
1976 | It will be easier to find the culprit if we die now. */ | |
341c100f | 1977 | gcc_assert (!((e->flags & EDGE_ABNORMAL) && EDGE_CRITICAL_P (e))); |
ca6c03ca | 1978 | |
6de9cd9a | 1979 | if (e->insns.r == NULL_RTX) |
ca6c03ca JH |
1980 | start_sequence (); |
1981 | else | |
6de9cd9a | 1982 | push_to_sequence (e->insns.r); |
ca6c03ca JH |
1983 | |
1984 | emit_insn (pattern); | |
1985 | ||
6de9cd9a | 1986 | e->insns.r = get_insns (); |
ca6c03ca JH |
1987 | end_sequence (); |
1988 | } | |
1989 | ||
2b4efc5d JJ |
1990 | /* Like insert_insn_on_edge, but if there are already queued instructions |
1991 | on the edge, PATTERN is prepended to them. */ | |
1992 | ||
1993 | void | |
1994 | prepend_insn_to_edge (rtx pattern, edge e) | |
1995 | { | |
1996 | /* We cannot insert instructions on an abnormal critical edge. | |
1997 | It will be easier to find the culprit if we die now. */ | |
1998 | gcc_assert (!((e->flags & EDGE_ABNORMAL) && EDGE_CRITICAL_P (e))); | |
1999 | ||
2000 | start_sequence (); | |
2001 | ||
2002 | emit_insn (pattern); | |
2003 | emit_insn (e->insns.r); | |
2004 | ||
2005 | e->insns.r = get_insns (); | |
2006 | end_sequence (); | |
2007 | } | |
2008 | ||
ca6c03ca JH |
2009 | /* Update the CFG for the instructions queued on edge E. */ |
2010 | ||
4e3825db | 2011 | void |
2ac66157 | 2012 | commit_one_edge_insertion (edge e) |
ca6c03ca | 2013 | { |
8879d71c | 2014 | rtx_insn *before = NULL, *after = NULL, *insns, *tmp, *last; |
898c90c0 | 2015 | basic_block bb; |
ca6c03ca JH |
2016 | |
2017 | /* Pull the insns off the edge now since the edge might go away. */ | |
3ffa95c2 DM |
2018 | insns = e->insns.r; |
2019 | e->insns.r = NULL; | |
ca6c03ca | 2020 | |
4f7d4a2c RS |
2021 | /* Allow the sequence to contain internal jumps, such as a memcpy loop |
2022 | or an allocation loop. If such a sequence is emitted during RTL | |
2023 | expansion, we'll create the appropriate basic blocks later, | |
2024 | at the end of the pass. But if such a sequence is emitted after | |
2025 | initial expansion, we'll need to find the subblocks ourselves. */ | |
2026 | bool contains_jump = false; | |
2027 | if (!currently_expanding_to_rtl) | |
2028 | for (rtx_insn *insn = insns; insn; insn = NEXT_INSN (insn)) | |
2029 | if (JUMP_P (insn)) | |
2030 | { | |
2031 | rebuild_jump_labels_chain (insns); | |
2032 | contains_jump = true; | |
2033 | break; | |
2034 | } | |
2035 | ||
898c90c0 EB |
2036 | /* Figure out where to put these insns. If the destination has |
2037 | one predecessor, insert there. Except for the exit block. */ | |
fefa31b5 | 2038 | if (single_pred_p (e->dest) && e->dest != EXIT_BLOCK_PTR_FOR_FN (cfun)) |
ca6c03ca | 2039 | { |
898c90c0 EB |
2040 | bb = e->dest; |
2041 | ||
2042 | /* Get the location correct wrt a code label, and "nice" wrt | |
2043 | a basic block note, and before everything else. */ | |
2044 | tmp = BB_HEAD (bb); | |
2045 | if (LABEL_P (tmp)) | |
2046 | tmp = NEXT_INSN (tmp); | |
2047 | if (NOTE_INSN_BASIC_BLOCK_P (tmp)) | |
2048 | tmp = NEXT_INSN (tmp); | |
2049 | if (tmp == BB_HEAD (bb)) | |
2050 | before = tmp; | |
2051 | else if (tmp) | |
2052 | after = PREV_INSN (tmp); | |
2053 | else | |
2054 | after = get_last_insn (); | |
2055 | } | |
3dec4024 | 2056 | |
898c90c0 | 2057 | /* If the source has one successor and the edge is not abnormal, |
a1d50386 JJ |
2058 | insert there. Except for the entry block. |
2059 | Don't do this if the predecessor ends in a jump other than | |
2060 | unconditional simple jump. E.g. for asm goto that points all | |
2061 | its labels at the fallthru basic block, we can't insert instructions | |
2062 | before the asm goto, as the asm goto can have various of side effects, | |
2063 | and can't emit instructions after the asm goto, as it must end | |
2064 | the basic block. */ | |
898c90c0 EB |
2065 | else if ((e->flags & EDGE_ABNORMAL) == 0 |
2066 | && single_succ_p (e->src) | |
fefa31b5 | 2067 | && e->src != ENTRY_BLOCK_PTR_FOR_FN (cfun) |
a1d50386 JJ |
2068 | && (!JUMP_P (BB_END (e->src)) |
2069 | || simplejump_p (BB_END (e->src)))) | |
898c90c0 EB |
2070 | { |
2071 | bb = e->src; | |
3dec4024 | 2072 | |
898c90c0 EB |
2073 | /* It is possible to have a non-simple jump here. Consider a target |
2074 | where some forms of unconditional jumps clobber a register. This | |
2075 | happens on the fr30 for example. | |
ca6c03ca | 2076 | |
898c90c0 EB |
2077 | We know this block has a single successor, so we can just emit |
2078 | the queued insns before the jump. */ | |
2079 | if (JUMP_P (BB_END (bb))) | |
2080 | before = BB_END (bb); | |
3dec4024 JH |
2081 | else |
2082 | { | |
898c90c0 EB |
2083 | /* We'd better be fallthru, or we've lost track of what's what. */ |
2084 | gcc_assert (e->flags & EDGE_FALLTHRU); | |
750054a2 | 2085 | |
898c90c0 | 2086 | after = BB_END (bb); |
ca6c03ca JH |
2087 | } |
2088 | } | |
2089 | ||
898c90c0 EB |
2090 | /* Otherwise we must split the edge. */ |
2091 | else | |
2092 | { | |
2093 | bb = split_edge (e); | |
3371a64f TJ |
2094 | |
2095 | /* If E crossed a partition boundary, we needed to make bb end in | |
2096 | a region-crossing jump, even though it was originally fallthru. */ | |
2097 | if (JUMP_P (BB_END (bb))) | |
2098 | before = BB_END (bb); | |
2099 | else | |
2100 | after = BB_END (bb); | |
898c90c0 EB |
2101 | } |
2102 | ||
2103 | /* Now that we've found the spot, do the insertion. */ | |
ca6c03ca JH |
2104 | if (before) |
2105 | { | |
6fb5fa3c | 2106 | emit_insn_before_noloc (insns, before, bb); |
ca6c03ca JH |
2107 | last = prev_nonnote_insn (before); |
2108 | } | |
2109 | else | |
6fb5fa3c | 2110 | last = emit_insn_after_noloc (insns, after, bb); |
ca6c03ca JH |
2111 | |
2112 | if (returnjump_p (last)) | |
2113 | { | |
2114 | /* ??? Remove all outgoing edges from BB and add one for EXIT. | |
c22cacf3 MS |
2115 | This is not currently a problem because this only happens |
2116 | for the (single) epilogue, which already has a fallthru edge | |
2117 | to EXIT. */ | |
ca6c03ca | 2118 | |
c5cbcccf | 2119 | e = single_succ_edge (bb); |
fefa31b5 | 2120 | gcc_assert (e->dest == EXIT_BLOCK_PTR_FOR_FN (cfun) |
c5cbcccf | 2121 | && single_succ_p (bb) && (e->flags & EDGE_FALLTHRU)); |
ca6c03ca | 2122 | |
5f0d2358 | 2123 | e->flags &= ~EDGE_FALLTHRU; |
ca6c03ca | 2124 | emit_barrier_after (last); |
0b17ab2f | 2125 | |
ca6c03ca JH |
2126 | if (before) |
2127 | delete_insn (before); | |
2128 | } | |
341c100f | 2129 | else |
4f7d4a2c RS |
2130 | /* Sequences inserted after RTL expansion are expected to be SESE, |
2131 | with only internal branches allowed. If the sequence jumps outside | |
2132 | itself then we do not know how to add the associated edges here. */ | |
672db38c | 2133 | gcc_assert (!JUMP_P (last) || currently_expanding_to_rtl); |
4f7d4a2c RS |
2134 | |
2135 | if (contains_jump) | |
2136 | find_sub_basic_blocks (bb); | |
ca6c03ca JH |
2137 | } |
2138 | ||
2139 | /* Update the CFG for all queued instructions. */ | |
2140 | ||
2141 | void | |
d329e058 | 2142 | commit_edge_insertions (void) |
ca6c03ca | 2143 | { |
ca6c03ca JH |
2144 | basic_block bb; |
2145 | ||
600b5b1d TJ |
2146 | /* Optimization passes that invoke this routine can cause hot blocks |
2147 | previously reached by both hot and cold blocks to become dominated only | |
2148 | by cold blocks. This will cause the verification below to fail, | |
2149 | and lead to now cold code in the hot section. In some cases this | |
2150 | may only be visible after newly unreachable blocks are deleted, | |
2151 | which will be done by fixup_partitions. */ | |
2152 | fixup_partitions (); | |
2153 | ||
82cea5e8 EB |
2154 | if (!currently_expanding_to_rtl) |
2155 | checking_verify_flow_info (); | |
ca6c03ca | 2156 | |
fefa31b5 DM |
2157 | FOR_BB_BETWEEN (bb, ENTRY_BLOCK_PTR_FOR_FN (cfun), |
2158 | EXIT_BLOCK_PTR_FOR_FN (cfun), next_bb) | |
ca6c03ca | 2159 | { |
628f6a4e BE |
2160 | edge e; |
2161 | edge_iterator ei; | |
ca6c03ca | 2162 | |
628f6a4e BE |
2163 | FOR_EACH_EDGE (e, ei, bb->succs) |
2164 | if (e->insns.r) | |
fe51b129 EB |
2165 | { |
2166 | if (currently_expanding_to_rtl) | |
2167 | rebuild_jump_labels_chain (e->insns.r); | |
2168 | commit_one_edge_insertion (e); | |
2169 | } | |
3dec4024 | 2170 | } |
ca6c03ca JH |
2171 | } |
2172 | \f | |
6fb5fa3c | 2173 | |
f470c378 | 2174 | /* Print out RTL-specific basic block information (live information |
a315c44c SB |
2175 | at start and end with TDF_DETAILS). FLAGS are the TDF_* masks |
2176 | documented in dumpfile.h. */ | |
ca6c03ca | 2177 | |
10e9fecc | 2178 | static void |
1a817418 | 2179 | rtl_dump_bb (FILE *outf, basic_block bb, int indent, dump_flags_t flags) |
ca6c03ca | 2180 | { |
f470c378 | 2181 | char *s_indent; |
ca6c03ca | 2182 | |
ae50c0cb | 2183 | s_indent = (char *) alloca ((size_t) indent + 1); |
400e39e3 | 2184 | memset (s_indent, ' ', (size_t) indent); |
f470c378 | 2185 | s_indent[indent] = '\0'; |
b8698a0f | 2186 | |
a315c44c | 2187 | if (df && (flags & TDF_DETAILS)) |
6fb5fa3c DB |
2188 | { |
2189 | df_dump_top (bb, outf); | |
2190 | putc ('\n', outf); | |
2191 | } | |
ca6c03ca | 2192 | |
4380d5ae IL |
2193 | if (bb->index != ENTRY_BLOCK && bb->index != EXIT_BLOCK |
2194 | && rtl_bb_info_initialized_p (bb)) | |
9fcaf059 SB |
2195 | { |
2196 | rtx_insn *last = BB_END (bb); | |
2197 | if (last) | |
2198 | last = NEXT_INSN (last); | |
2199 | for (rtx_insn *insn = BB_HEAD (bb); insn != last; insn = NEXT_INSN (insn)) | |
2200 | { | |
2201 | if (flags & TDF_DETAILS) | |
2202 | df_dump_insn_top (insn, outf); | |
2203 | if (! (flags & TDF_SLIM)) | |
2204 | print_rtl_single (outf, insn); | |
2205 | else | |
2206 | dump_insn_slim (outf, insn); | |
2207 | if (flags & TDF_DETAILS) | |
2208 | df_dump_insn_bottom (insn, outf); | |
2209 | } | |
2210 | } | |
a315c44c SB |
2211 | |
2212 | if (df && (flags & TDF_DETAILS)) | |
6fb5fa3c DB |
2213 | { |
2214 | df_dump_bottom (bb, outf); | |
2215 | putc ('\n', outf); | |
2216 | } | |
2217 | ||
ca6c03ca JH |
2218 | } |
2219 | \f | |
c4669594 SB |
2220 | /* Like dump_function_to_file, but for RTL. Print out dataflow information |
2221 | for the start of each basic block. FLAGS are the TDF_* masks documented | |
2222 | in dumpfile.h. */ | |
ca6c03ca JH |
2223 | |
2224 | void | |
1a817418 | 2225 | print_rtl_with_bb (FILE *outf, const rtx_insn *rtx_first, dump_flags_t flags) |
ca6c03ca | 2226 | { |
b2908ba6 | 2227 | const rtx_insn *tmp_rtx; |
ca6c03ca JH |
2228 | if (rtx_first == 0) |
2229 | fprintf (outf, "(nil)\n"); | |
2230 | else | |
2231 | { | |
ca6c03ca JH |
2232 | enum bb_state { NOT_IN_BB, IN_ONE_BB, IN_MULTIPLE_BB }; |
2233 | int max_uid = get_max_uid (); | |
5ed6ace5 MD |
2234 | basic_block *start = XCNEWVEC (basic_block, max_uid); |
2235 | basic_block *end = XCNEWVEC (basic_block, max_uid); | |
2236 | enum bb_state *in_bb_p = XCNEWVEC (enum bb_state, max_uid); | |
e0082a72 ZD |
2237 | basic_block bb; |
2238 | ||
c4669594 SB |
2239 | /* After freeing the CFG, we still have BLOCK_FOR_INSN set on most |
2240 | insns, but the CFG is not maintained so the basic block info | |
2241 | is not reliable. Therefore it's omitted from the dumps. */ | |
2242 | if (! (cfun->curr_properties & PROP_cfg)) | |
2243 | flags &= ~TDF_BLOCKS; | |
2244 | ||
6fb5fa3c DB |
2245 | if (df) |
2246 | df_dump_start (outf); | |
2247 | ||
33627377 | 2248 | if (cfun->curr_properties & PROP_cfg) |
ca6c03ca | 2249 | { |
4f42035e | 2250 | FOR_EACH_BB_REVERSE_FN (bb, cfun) |
ca6c03ca | 2251 | { |
8879d71c | 2252 | rtx_insn *x; |
c4669594 SB |
2253 | |
2254 | start[INSN_UID (BB_HEAD (bb))] = bb; | |
2255 | end[INSN_UID (BB_END (bb))] = bb; | |
33627377 | 2256 | if (flags & TDF_BLOCKS) |
c4669594 | 2257 | { |
33627377 KL |
2258 | for (x = BB_HEAD (bb); x != NULL_RTX; x = NEXT_INSN (x)) |
2259 | { | |
2260 | enum bb_state state = IN_MULTIPLE_BB; | |
5f0d2358 | 2261 | |
33627377 KL |
2262 | if (in_bb_p[INSN_UID (x)] == NOT_IN_BB) |
2263 | state = IN_ONE_BB; | |
2264 | in_bb_p[INSN_UID (x)] = state; | |
ca6c03ca | 2265 | |
33627377 KL |
2266 | if (x == BB_END (bb)) |
2267 | break; | |
2268 | } | |
c4669594 | 2269 | } |
ca6c03ca JH |
2270 | } |
2271 | } | |
2272 | ||
01512446 | 2273 | for (tmp_rtx = rtx_first; tmp_rtx != NULL; tmp_rtx = NEXT_INSN (tmp_rtx)) |
ca6c03ca | 2274 | { |
c4669594 SB |
2275 | if (flags & TDF_BLOCKS) |
2276 | { | |
2277 | bb = start[INSN_UID (tmp_rtx)]; | |
2278 | if (bb != NULL) | |
2279 | { | |
9d9573d5 | 2280 | dump_bb_info (outf, bb, 0, dump_flags, true, false); |
c4669594 SB |
2281 | if (df && (flags & TDF_DETAILS)) |
2282 | df_dump_top (bb, outf); | |
2283 | } | |
ca6c03ca | 2284 | |
c4669594 SB |
2285 | if (in_bb_p[INSN_UID (tmp_rtx)] == NOT_IN_BB |
2286 | && !NOTE_P (tmp_rtx) | |
2287 | && !BARRIER_P (tmp_rtx)) | |
2288 | fprintf (outf, ";; Insn is not within a basic block\n"); | |
2289 | else if (in_bb_p[INSN_UID (tmp_rtx)] == IN_MULTIPLE_BB) | |
2290 | fprintf (outf, ";; Insn is in multiple basic blocks\n"); | |
2291 | } | |
ca6c03ca | 2292 | |
7b19209f SB |
2293 | if (flags & TDF_DETAILS) |
2294 | df_dump_insn_top (tmp_rtx, outf); | |
a315c44c SB |
2295 | if (! (flags & TDF_SLIM)) |
2296 | print_rtl_single (outf, tmp_rtx); | |
2297 | else | |
2298 | dump_insn_slim (outf, tmp_rtx); | |
7b19209f SB |
2299 | if (flags & TDF_DETAILS) |
2300 | df_dump_insn_bottom (tmp_rtx, outf); | |
ca6c03ca | 2301 | |
33627377 KL |
2302 | bb = end[INSN_UID (tmp_rtx)]; |
2303 | if (bb != NULL) | |
c4669594 | 2304 | { |
33627377 | 2305 | if (flags & TDF_BLOCKS) |
c4669594 | 2306 | { |
9d9573d5 | 2307 | dump_bb_info (outf, bb, 0, dump_flags, false, true); |
c4669594 SB |
2308 | if (df && (flags & TDF_DETAILS)) |
2309 | df_dump_bottom (bb, outf); | |
1b03a96d | 2310 | putc ('\n', outf); |
c4669594 | 2311 | } |
33627377 KL |
2312 | /* Emit a hint if the fallthrough target of current basic block |
2313 | isn't the one placed right next. */ | |
2314 | else if (EDGE_COUNT (bb->succs) > 0) | |
2315 | { | |
2316 | gcc_assert (BB_END (bb) == tmp_rtx); | |
2317 | const rtx_insn *ninsn = NEXT_INSN (tmp_rtx); | |
2318 | /* Bypass intervening deleted-insn notes and debug insns. */ | |
2319 | while (ninsn | |
2320 | && !NONDEBUG_INSN_P (ninsn) | |
2321 | && !start[INSN_UID (ninsn)]) | |
2322 | ninsn = NEXT_INSN (ninsn); | |
2323 | edge e = find_fallthru_edge (bb->succs); | |
2324 | if (e && ninsn) | |
2325 | { | |
2326 | basic_block dest = e->dest; | |
2327 | if (start[INSN_UID (ninsn)] != dest) | |
2328 | fprintf (outf, "%s ; pc falls through to BB %d\n", | |
2329 | print_rtx_head, dest->index); | |
2330 | } | |
2331 | } | |
c4669594 | 2332 | } |
ca6c03ca JH |
2333 | } |
2334 | ||
2335 | free (start); | |
2336 | free (end); | |
2337 | free (in_bb_p); | |
2338 | } | |
ca6c03ca JH |
2339 | } |
2340 | \f | |
532aafad SB |
2341 | /* Update the branch probability of BB if a REG_BR_PROB is present. */ |
2342 | ||
b446e5a2 | 2343 | void |
d329e058 | 2344 | update_br_prob_note (basic_block bb) |
b446e5a2 JH |
2345 | { |
2346 | rtx note; | |
a813c111 | 2347 | note = find_reg_note (BB_END (bb), REG_BR_PROB, NULL_RTX); |
e7a74006 JH |
2348 | if (!JUMP_P (BB_END (bb)) || !BRANCH_EDGE (bb)->probability.initialized_p ()) |
2349 | { | |
2350 | if (note) | |
2351 | { | |
2352 | rtx *note_link, this_rtx; | |
2353 | ||
2354 | note_link = ®_NOTES (BB_END (bb)); | |
2355 | for (this_rtx = *note_link; this_rtx; this_rtx = XEXP (this_rtx, 1)) | |
2356 | if (this_rtx == note) | |
2357 | { | |
2358 | *note_link = XEXP (this_rtx, 1); | |
2359 | break; | |
2360 | } | |
2361 | } | |
2362 | return; | |
2363 | } | |
357067f2 | 2364 | if (!note |
5fa396ad | 2365 | || XINT (note, 0) == BRANCH_EDGE (bb)->probability.to_reg_br_prob_note ()) |
b446e5a2 | 2366 | return; |
5fa396ad | 2367 | XINT (note, 0) = BRANCH_EDGE (bb)->probability.to_reg_br_prob_note (); |
b446e5a2 | 2368 | } |
96370780 MK |
2369 | |
2370 | /* Get the last insn associated with block BB (that includes barriers and | |
2371 | tablejumps after BB). */ | |
636eb204 | 2372 | rtx_insn * |
96370780 MK |
2373 | get_last_bb_insn (basic_block bb) |
2374 | { | |
8942ee0f | 2375 | rtx_jump_table_data *table; |
636eb204 DM |
2376 | rtx_insn *tmp; |
2377 | rtx_insn *end = BB_END (bb); | |
96370780 MK |
2378 | |
2379 | /* Include any jump table following the basic block. */ | |
8942ee0f DM |
2380 | if (tablejump_p (end, NULL, &table)) |
2381 | end = table; | |
96370780 MK |
2382 | |
2383 | /* Include any barriers that may follow the basic block. */ | |
f40dd646 | 2384 | tmp = next_nonnote_nondebug_insn_bb (end); |
96370780 MK |
2385 | while (tmp && BARRIER_P (tmp)) |
2386 | { | |
2387 | end = tmp; | |
f40dd646 | 2388 | tmp = next_nonnote_nondebug_insn_bb (end); |
96370780 MK |
2389 | } |
2390 | ||
2391 | return end; | |
2392 | } | |
af205f67 | 2393 | |
d9af4fea JH |
2394 | /* Add all BBs reachable from entry via hot paths into the SET. */ |
2395 | ||
2396 | void | |
2397 | find_bbs_reachable_by_hot_paths (hash_set<basic_block> *set) | |
2398 | { | |
2399 | auto_vec<basic_block, 64> worklist; | |
2400 | ||
2401 | set->add (ENTRY_BLOCK_PTR_FOR_FN (cfun)); | |
2402 | worklist.safe_push (ENTRY_BLOCK_PTR_FOR_FN (cfun)); | |
2403 | ||
2404 | while (worklist.length () > 0) | |
2405 | { | |
2406 | basic_block bb = worklist.pop (); | |
2407 | edge_iterator ei; | |
2408 | edge e; | |
2409 | ||
2410 | FOR_EACH_EDGE (e, ei, bb->succs) | |
2411 | if (BB_PARTITION (e->dest) != BB_COLD_PARTITION | |
2412 | && !set->add (e->dest)) | |
2413 | worklist.safe_push (e->dest); | |
2414 | } | |
2415 | } | |
2416 | ||
600b5b1d TJ |
2417 | /* Sanity check partition hotness to ensure that basic blocks in |
2418 | the cold partition don't dominate basic blocks in the hot partition. | |
2419 | If FLAG_ONLY is true, report violations as errors. Otherwise | |
2420 | re-mark the dominated blocks as cold, since this is run after | |
2421 | cfg optimizations that may make hot blocks previously reached | |
2422 | by both hot and cold blocks now only reachable along cold paths. */ | |
2423 | ||
72932511 | 2424 | static auto_vec<basic_block> |
600b5b1d TJ |
2425 | find_partition_fixes (bool flag_only) |
2426 | { | |
2427 | basic_block bb; | |
72932511 | 2428 | auto_vec<basic_block> bbs_to_fix; |
d9af4fea | 2429 | hash_set<basic_block> set; |
600b5b1d TJ |
2430 | |
2431 | /* Callers check this. */ | |
2432 | gcc_checking_assert (crtl->has_bb_partition); | |
2433 | ||
d9af4fea | 2434 | find_bbs_reachable_by_hot_paths (&set); |
600b5b1d | 2435 | |
d9af4fea JH |
2436 | FOR_EACH_BB_FN (bb, cfun) |
2437 | if (!set.contains (bb) | |
2438 | && BB_PARTITION (bb) != BB_COLD_PARTITION) | |
2439 | { | |
2440 | if (flag_only) | |
2441 | error ("non-cold basic block %d reachable only " | |
2442 | "by paths crossing the cold partition", bb->index); | |
2443 | else | |
2444 | BB_SET_PARTITION (bb, BB_COLD_PARTITION); | |
2445 | bbs_to_fix.safe_push (bb); | |
d9af4fea | 2446 | } |
600b5b1d TJ |
2447 | |
2448 | return bbs_to_fix; | |
2449 | } | |
2450 | ||
2451 | /* Perform cleanup on the hot/cold bb partitioning after optimization | |
2452 | passes that modify the cfg. */ | |
2453 | ||
2454 | void | |
2455 | fixup_partitions (void) | |
2456 | { | |
600b5b1d TJ |
2457 | if (!crtl->has_bb_partition) |
2458 | return; | |
2459 | ||
2460 | /* Delete any blocks that became unreachable and weren't | |
2461 | already cleaned up, for example during edge forwarding | |
2462 | and convert_jumps_to_returns. This will expose more | |
2463 | opportunities for fixing the partition boundaries here. | |
2464 | Also, the calculation of the dominance graph during verification | |
2465 | will assert if there are unreachable nodes. */ | |
2466 | delete_unreachable_blocks (); | |
2467 | ||
2468 | /* If there are partitions, do a sanity check on them: A basic block in | |
2469 | a cold partition cannot dominate a basic block in a hot partition. | |
2470 | Fixup any that now violate this requirement, as a result of edge | |
2471 | forwarding and unreachable block deletion. */ | |
72932511 | 2472 | auto_vec<basic_block> bbs_to_fix = find_partition_fixes (false); |
600b5b1d TJ |
2473 | |
2474 | /* Do the partition fixup after all necessary blocks have been converted to | |
2475 | cold, so that we only update the region crossings the minimum number of | |
2476 | places, which can require forcing edges to be non fallthru. */ | |
4ad5b191 | 2477 | if (! bbs_to_fix.is_empty ()) |
600b5b1d | 2478 | { |
4ad5b191 JJ |
2479 | do |
2480 | { | |
2481 | basic_block bb = bbs_to_fix.pop (); | |
2482 | fixup_new_cold_bb (bb); | |
2483 | } | |
2484 | while (! bbs_to_fix.is_empty ()); | |
2485 | ||
2486 | /* Fix up hot cold block grouping if needed. */ | |
2487 | if (crtl->bb_reorder_complete && current_ir_type () == IR_RTL_CFGRTL) | |
2488 | { | |
2489 | basic_block bb, first = NULL, second = NULL; | |
2490 | int current_partition = BB_UNPARTITIONED; | |
2491 | ||
2492 | FOR_EACH_BB_FN (bb, cfun) | |
2493 | { | |
2494 | if (current_partition != BB_UNPARTITIONED | |
2495 | && BB_PARTITION (bb) != current_partition) | |
2496 | { | |
2497 | if (first == NULL) | |
2498 | first = bb; | |
2499 | else if (second == NULL) | |
2500 | second = bb; | |
2501 | else | |
2502 | { | |
2503 | /* If we switch partitions for the 3rd, 5th etc. time, | |
2504 | move bbs first (inclusive) .. second (exclusive) right | |
2505 | before bb. */ | |
2506 | basic_block prev_first = first->prev_bb; | |
2507 | basic_block prev_second = second->prev_bb; | |
2508 | basic_block prev_bb = bb->prev_bb; | |
2509 | prev_first->next_bb = second; | |
2510 | second->prev_bb = prev_first; | |
2511 | prev_second->next_bb = bb; | |
2512 | bb->prev_bb = prev_second; | |
2513 | prev_bb->next_bb = first; | |
2514 | first->prev_bb = prev_bb; | |
2515 | rtx_insn *prev_first_insn = PREV_INSN (BB_HEAD (first)); | |
2516 | rtx_insn *prev_second_insn | |
2517 | = PREV_INSN (BB_HEAD (second)); | |
2518 | rtx_insn *prev_bb_insn = PREV_INSN (BB_HEAD (bb)); | |
2519 | SET_NEXT_INSN (prev_first_insn) = BB_HEAD (second); | |
2520 | SET_PREV_INSN (BB_HEAD (second)) = prev_first_insn; | |
2521 | SET_NEXT_INSN (prev_second_insn) = BB_HEAD (bb); | |
2522 | SET_PREV_INSN (BB_HEAD (bb)) = prev_second_insn; | |
2523 | SET_NEXT_INSN (prev_bb_insn) = BB_HEAD (first); | |
2524 | SET_PREV_INSN (BB_HEAD (first)) = prev_bb_insn; | |
2525 | second = NULL; | |
2526 | } | |
2527 | } | |
2528 | current_partition = BB_PARTITION (bb); | |
2529 | } | |
2530 | gcc_assert (!second); | |
2531 | } | |
600b5b1d TJ |
2532 | } |
2533 | } | |
2534 | ||
af205f67 TJ |
2535 | /* Verify, in the basic block chain, that there is at most one switch |
2536 | between hot/cold partitions. This condition will not be true until | |
2537 | after reorder_basic_blocks is called. */ | |
2538 | ||
47bd5598 | 2539 | static bool |
af205f67 TJ |
2540 | verify_hot_cold_block_grouping (void) |
2541 | { | |
2542 | basic_block bb; | |
47bd5598 | 2543 | bool err = false; |
af205f67 TJ |
2544 | bool switched_sections = false; |
2545 | int current_partition = BB_UNPARTITIONED; | |
2546 | ||
3371a64f TJ |
2547 | /* Even after bb reordering is complete, we go into cfglayout mode |
2548 | again (in compgoto). Ensure we don't call this before going back | |
2549 | into linearized RTL when any layout fixes would have been committed. */ | |
2550 | if (!crtl->bb_reorder_complete | |
c3284718 | 2551 | || current_ir_type () != IR_RTL_CFGRTL) |
251a41b9 | 2552 | return err; |
af205f67 | 2553 | |
11cd3bed | 2554 | FOR_EACH_BB_FN (bb, cfun) |
af205f67 TJ |
2555 | { |
2556 | if (current_partition != BB_UNPARTITIONED | |
2557 | && BB_PARTITION (bb) != current_partition) | |
2558 | { | |
2559 | if (switched_sections) | |
2560 | { | |
2561 | error ("multiple hot/cold transitions found (bb %i)", | |
2562 | bb->index); | |
47bd5598 | 2563 | err = true; |
af205f67 TJ |
2564 | } |
2565 | else | |
2566 | switched_sections = true; | |
2567 | ||
2568 | if (!crtl->has_bb_partition) | |
2569 | error ("partition found but function partition flag not set"); | |
2570 | } | |
2571 | current_partition = BB_PARTITION (bb); | |
2572 | } | |
2573 | ||
251a41b9 | 2574 | return err; |
af205f67 | 2575 | } |
b446e5a2 | 2576 | \f |
ca6c03ca | 2577 | |
251a41b9 TJ |
2578 | /* Perform several checks on the edges out of each block, such as |
2579 | the consistency of the branch probabilities, the correctness | |
2580 | of hot/cold partition crossing edges, and the number of expected | |
600b5b1d TJ |
2581 | successor edges. Also verify that the dominance relationship |
2582 | between hot/cold blocks is sane. */ | |
f470c378 | 2583 | |
47bd5598 | 2584 | static bool |
251a41b9 | 2585 | rtl_verify_edges (void) |
ca6c03ca | 2586 | { |
47bd5598 | 2587 | bool err = false; |
94eb5ddb | 2588 | basic_block bb; |
ca6c03ca | 2589 | |
4f42035e | 2590 | FOR_EACH_BB_REVERSE_FN (bb, cfun) |
ca6c03ca | 2591 | { |
f99ffaa3 EB |
2592 | int n_fallthru = 0, n_branch = 0, n_abnormal_call = 0, n_sibcall = 0; |
2593 | int n_eh = 0, n_abnormal = 0; | |
3cf54412 | 2594 | edge e, fallthru = NULL; |
628f6a4e | 2595 | edge_iterator ei; |
251a41b9 | 2596 | rtx note; |
3371a64f | 2597 | bool has_crossing_edge = false; |
ca6c03ca | 2598 | |
2085a21f | 2599 | if (JUMP_P (BB_END (bb)) |
a813c111 | 2600 | && (note = find_reg_note (BB_END (bb), REG_BR_PROB, NULL_RTX)) |
628f6a4e | 2601 | && EDGE_COUNT (bb->succs) >= 2 |
a813c111 | 2602 | && any_condjump_p (BB_END (bb))) |
5a1a3e5e | 2603 | { |
357067f2 JH |
2604 | if (!BRANCH_EDGE (bb)->probability.initialized_p ()) |
2605 | { | |
a4c57f86 | 2606 | if (profile_status_for_fn (cfun) != PROFILE_ABSENT) |
357067f2 | 2607 | { |
a4c57f86 JH |
2608 | error ("verify_flow_info: " |
2609 | "REG_BR_PROB is set but cfg probability is not"); | |
47bd5598 | 2610 | err = true; |
357067f2 JH |
2611 | } |
2612 | } | |
2613 | else if (XINT (note, 0) | |
5fa396ad | 2614 | != BRANCH_EDGE (bb)->probability.to_reg_br_prob_note () |
357067f2 | 2615 | && profile_status_for_fn (cfun) != PROFILE_ABSENT) |
5a1a3e5e | 2616 | { |
e5af9ddd | 2617 | error ("verify_flow_info: REG_BR_PROB does not match cfg %i %i", |
357067f2 | 2618 | XINT (note, 0), |
5fa396ad | 2619 | BRANCH_EDGE (bb)->probability.to_reg_br_prob_note ()); |
47bd5598 | 2620 | err = true; |
5a1a3e5e JH |
2621 | } |
2622 | } | |
251a41b9 | 2623 | |
628f6a4e | 2624 | FOR_EACH_EDGE (e, ei, bb->succs) |
ca6c03ca | 2625 | { |
0be7e7a6 RH |
2626 | bool is_crossing; |
2627 | ||
ca6c03ca | 2628 | if (e->flags & EDGE_FALLTHRU) |
0be7e7a6 RH |
2629 | n_fallthru++, fallthru = e; |
2630 | ||
2631 | is_crossing = (BB_PARTITION (e->src) != BB_PARTITION (e->dest) | |
fefa31b5 DM |
2632 | && e->src != ENTRY_BLOCK_PTR_FOR_FN (cfun) |
2633 | && e->dest != EXIT_BLOCK_PTR_FOR_FN (cfun)); | |
3371a64f | 2634 | has_crossing_edge |= is_crossing; |
0be7e7a6 | 2635 | if (e->flags & EDGE_CROSSING) |
750054a2 | 2636 | { |
0be7e7a6 RH |
2637 | if (!is_crossing) |
2638 | { | |
2639 | error ("EDGE_CROSSING incorrectly set across same section"); | |
47bd5598 | 2640 | err = true; |
0be7e7a6 RH |
2641 | } |
2642 | if (e->flags & EDGE_FALLTHRU) | |
2643 | { | |
f99ffaa3 | 2644 | error ("fallthru edge crosses section boundary in bb %i", |
750054a2 | 2645 | e->src->index); |
47bd5598 | 2646 | err = true; |
750054a2 | 2647 | } |
0be7e7a6 RH |
2648 | if (e->flags & EDGE_EH) |
2649 | { | |
f99ffaa3 | 2650 | error ("EH edge crosses section boundary in bb %i", |
0be7e7a6 | 2651 | e->src->index); |
47bd5598 | 2652 | err = true; |
0be7e7a6 | 2653 | } |
339ba33b | 2654 | if (JUMP_P (BB_END (bb)) && !CROSSING_JUMP_P (BB_END (bb))) |
3371a64f TJ |
2655 | { |
2656 | error ("No region crossing jump at section boundary in bb %i", | |
2657 | bb->index); | |
47bd5598 | 2658 | err = true; |
3371a64f | 2659 | } |
0be7e7a6 RH |
2660 | } |
2661 | else if (is_crossing) | |
2662 | { | |
2663 | error ("EDGE_CROSSING missing across section boundary"); | |
47bd5598 | 2664 | err = true; |
750054a2 | 2665 | } |
3dec4024 | 2666 | |
65f43cdf ZD |
2667 | if ((e->flags & ~(EDGE_DFS_BACK |
2668 | | EDGE_CAN_FALLTHRU | |
2669 | | EDGE_IRREDUCIBLE_LOOP | |
9beb1c84 | 2670 | | EDGE_LOOP_EXIT |
7e872b90 JJ |
2671 | | EDGE_CROSSING |
2672 | | EDGE_PRESERVE)) == 0) | |
3dec4024 JH |
2673 | n_branch++; |
2674 | ||
2675 | if (e->flags & EDGE_ABNORMAL_CALL) | |
f99ffaa3 EB |
2676 | n_abnormal_call++; |
2677 | ||
2678 | if (e->flags & EDGE_SIBCALL) | |
2679 | n_sibcall++; | |
3dec4024 JH |
2680 | |
2681 | if (e->flags & EDGE_EH) | |
2682 | n_eh++; | |
f99ffaa3 EB |
2683 | |
2684 | if (e->flags & EDGE_ABNORMAL) | |
3dec4024 | 2685 | n_abnormal++; |
ca6c03ca | 2686 | } |
5f0d2358 | 2687 | |
d53e8ef4 JJ |
2688 | if (!has_crossing_edge |
2689 | && JUMP_P (BB_END (bb)) | |
2690 | && CROSSING_JUMP_P (BB_END (bb))) | |
2691 | { | |
2692 | print_rtl_with_bb (stderr, get_insns (), TDF_BLOCKS | TDF_DETAILS); | |
2693 | error ("Region crossing jump across same section in bb %i", | |
2694 | bb->index); | |
47bd5598 | 2695 | err = true; |
d53e8ef4 | 2696 | } |
3371a64f | 2697 | |
1d65f45c | 2698 | if (n_eh && !find_reg_note (BB_END (bb), REG_EH_REGION, NULL_RTX)) |
3dec4024 | 2699 | { |
f99ffaa3 | 2700 | error ("missing REG_EH_REGION note at the end of bb %i", bb->index); |
47bd5598 | 2701 | err = true; |
3dec4024 | 2702 | } |
1d65f45c RH |
2703 | if (n_eh > 1) |
2704 | { | |
f99ffaa3 | 2705 | error ("too many exception handling edges in bb %i", bb->index); |
47bd5598 | 2706 | err = true; |
1d65f45c | 2707 | } |
3dec4024 | 2708 | if (n_branch |
4b4bf941 | 2709 | && (!JUMP_P (BB_END (bb)) |
a813c111 SB |
2710 | || (n_branch > 1 && (any_uncondjump_p (BB_END (bb)) |
2711 | || any_condjump_p (BB_END (bb)))))) | |
3dec4024 | 2712 | { |
ab532386 | 2713 | error ("too many outgoing branch edges from bb %i", bb->index); |
47bd5598 | 2714 | err = true; |
3dec4024 | 2715 | } |
a813c111 | 2716 | if (n_fallthru && any_uncondjump_p (BB_END (bb))) |
3dec4024 | 2717 | { |
f99ffaa3 | 2718 | error ("fallthru edge after unconditional jump in bb %i", bb->index); |
47bd5598 | 2719 | err = true; |
3dec4024 | 2720 | } |
a813c111 | 2721 | if (n_branch != 1 && any_uncondjump_p (BB_END (bb))) |
3dec4024 | 2722 | { |
f99ffaa3 EB |
2723 | error ("wrong number of branch edges after unconditional jump" |
2724 | " in bb %i", bb->index); | |
47bd5598 | 2725 | err = true; |
3dec4024 | 2726 | } |
a813c111 | 2727 | if (n_branch != 1 && any_condjump_p (BB_END (bb)) |
c11fd0b2 | 2728 | && JUMP_LABEL (BB_END (bb)) != BB_HEAD (fallthru->dest)) |
3dec4024 | 2729 | { |
f99ffaa3 EB |
2730 | error ("wrong amount of branch edges after conditional jump" |
2731 | " in bb %i", bb->index); | |
47bd5598 | 2732 | err = true; |
f99ffaa3 EB |
2733 | } |
2734 | if (n_abnormal_call && !CALL_P (BB_END (bb))) | |
2735 | { | |
2736 | error ("abnormal call edges for non-call insn in bb %i", bb->index); | |
47bd5598 | 2737 | err = true; |
3dec4024 | 2738 | } |
f99ffaa3 | 2739 | if (n_sibcall && !CALL_P (BB_END (bb))) |
3dec4024 | 2740 | { |
f99ffaa3 | 2741 | error ("sibcall edges for non-call insn in bb %i", bb->index); |
47bd5598 | 2742 | err = true; |
3dec4024 | 2743 | } |
f99ffaa3 EB |
2744 | if (n_abnormal > n_eh |
2745 | && !(CALL_P (BB_END (bb)) | |
2746 | && n_abnormal == n_abnormal_call + n_sibcall) | |
4b4bf941 | 2747 | && (!JUMP_P (BB_END (bb)) |
a813c111 SB |
2748 | || any_condjump_p (BB_END (bb)) |
2749 | || any_uncondjump_p (BB_END (bb)))) | |
3dec4024 | 2750 | { |
ab532386 | 2751 | error ("abnormal edges for no purpose in bb %i", bb->index); |
47bd5598 | 2752 | err = true; |
3dec4024 | 2753 | } |
d53e8ef4 JJ |
2754 | |
2755 | int has_eh = -1; | |
2756 | FOR_EACH_EDGE (e, ei, bb->preds) | |
2757 | { | |
2758 | if (has_eh == -1) | |
2759 | has_eh = (e->flags & EDGE_EH); | |
2760 | if ((e->flags & EDGE_EH) == has_eh) | |
2761 | continue; | |
2762 | error ("EH incoming edge mixed with non-EH incoming edges " | |
2763 | "in bb %i", bb->index); | |
47bd5598 | 2764 | err = true; |
d53e8ef4 JJ |
2765 | break; |
2766 | } | |
251a41b9 | 2767 | } |
f87c27b4 | 2768 | |
600b5b1d TJ |
2769 | /* If there are partitions, do a sanity check on them: A basic block in |
2770 | a cold partition cannot dominate a basic block in a hot partition. */ | |
3211aea2 JH |
2771 | if (crtl->has_bb_partition && !err |
2772 | && current_ir_type () == IR_RTL_CFGLAYOUT) | |
600b5b1d | 2773 | { |
72932511 | 2774 | auto_vec<basic_block> bbs_to_fix = find_partition_fixes (true); |
600b5b1d TJ |
2775 | err = !bbs_to_fix.is_empty (); |
2776 | } | |
2777 | ||
251a41b9 TJ |
2778 | /* Clean up. */ |
2779 | return err; | |
2780 | } | |
5f0d2358 | 2781 | |
251a41b9 TJ |
2782 | /* Checks on the instructions within blocks. Currently checks that each |
2783 | block starts with a basic block note, and that basic block notes and | |
2784 | control flow jumps are not found in the middle of the block. */ | |
ca6c03ca | 2785 | |
47bd5598 | 2786 | static bool |
251a41b9 TJ |
2787 | rtl_verify_bb_insns (void) |
2788 | { | |
8879d71c | 2789 | rtx_insn *x; |
47bd5598 | 2790 | bool err = false; |
251a41b9 TJ |
2791 | basic_block bb; |
2792 | ||
4f42035e | 2793 | FOR_EACH_BB_REVERSE_FN (bb, cfun) |
251a41b9 TJ |
2794 | { |
2795 | /* Now check the header of basic | |
c22cacf3 | 2796 | block. It ought to contain optional CODE_LABEL followed |
ca6c03ca | 2797 | by NOTE_BASIC_BLOCK. */ |
a813c111 | 2798 | x = BB_HEAD (bb); |
4b4bf941 | 2799 | if (LABEL_P (x)) |
ca6c03ca | 2800 | { |
a813c111 | 2801 | if (BB_END (bb) == x) |
ca6c03ca JH |
2802 | { |
2803 | error ("NOTE_INSN_BASIC_BLOCK is missing for block %d", | |
0b17ab2f | 2804 | bb->index); |
47bd5598 | 2805 | err = true; |
ca6c03ca | 2806 | } |
5f0d2358 | 2807 | |
ca6c03ca JH |
2808 | x = NEXT_INSN (x); |
2809 | } | |
5f0d2358 | 2810 | |
ca6c03ca JH |
2811 | if (!NOTE_INSN_BASIC_BLOCK_P (x) || NOTE_BASIC_BLOCK (x) != bb) |
2812 | { | |
2813 | error ("NOTE_INSN_BASIC_BLOCK is missing for block %d", | |
0b17ab2f | 2814 | bb->index); |
47bd5598 | 2815 | err = true; |
ca6c03ca JH |
2816 | } |
2817 | ||
a813c111 | 2818 | if (BB_END (bb) == x) |
49243025 | 2819 | /* Do checks for empty blocks here. */ |
5f0d2358 | 2820 | ; |
ca6c03ca | 2821 | else |
5f0d2358 RK |
2822 | for (x = NEXT_INSN (x); x; x = NEXT_INSN (x)) |
2823 | { | |
2824 | if (NOTE_INSN_BASIC_BLOCK_P (x)) | |
2825 | { | |
2826 | error ("NOTE_INSN_BASIC_BLOCK %d in middle of basic block %d", | |
0b17ab2f | 2827 | INSN_UID (x), bb->index); |
47bd5598 | 2828 | err = true; |
5f0d2358 RK |
2829 | } |
2830 | ||
a813c111 | 2831 | if (x == BB_END (bb)) |
5f0d2358 | 2832 | break; |
ca6c03ca | 2833 | |
83fd323c | 2834 | if (control_flow_insn_p (x)) |
5f0d2358 | 2835 | { |
0b17ab2f | 2836 | error ("in basic block %d:", bb->index); |
5f0d2358 RK |
2837 | fatal_insn ("flow control insn inside a basic block", x); |
2838 | } | |
2839 | } | |
ca6c03ca JH |
2840 | } |
2841 | ||
251a41b9 TJ |
2842 | /* Clean up. */ |
2843 | return err; | |
2844 | } | |
2845 | ||
2846 | /* Verify that block pointers for instructions in basic blocks, headers and | |
2847 | footers are set appropriately. */ | |
2848 | ||
47bd5598 | 2849 | static bool |
251a41b9 TJ |
2850 | rtl_verify_bb_pointers (void) |
2851 | { | |
47bd5598 | 2852 | bool err = false; |
251a41b9 TJ |
2853 | basic_block bb; |
2854 | ||
2855 | /* Check the general integrity of the basic blocks. */ | |
4f42035e | 2856 | FOR_EACH_BB_REVERSE_FN (bb, cfun) |
251a41b9 | 2857 | { |
8879d71c | 2858 | rtx_insn *insn; |
251a41b9 TJ |
2859 | |
2860 | if (!(bb->flags & BB_RTL)) | |
2861 | { | |
2862 | error ("BB_RTL flag not set for block %d", bb->index); | |
47bd5598 | 2863 | err = true; |
251a41b9 TJ |
2864 | } |
2865 | ||
2866 | FOR_BB_INSNS (bb, insn) | |
2867 | if (BLOCK_FOR_INSN (insn) != bb) | |
2868 | { | |
2869 | error ("insn %d basic block pointer is %d, should be %d", | |
2870 | INSN_UID (insn), | |
2871 | BLOCK_FOR_INSN (insn) ? BLOCK_FOR_INSN (insn)->index : 0, | |
2872 | bb->index); | |
47bd5598 | 2873 | err = true; |
251a41b9 TJ |
2874 | } |
2875 | ||
2876 | for (insn = BB_HEADER (bb); insn; insn = NEXT_INSN (insn)) | |
2877 | if (!BARRIER_P (insn) | |
2878 | && BLOCK_FOR_INSN (insn) != NULL) | |
2879 | { | |
2880 | error ("insn %d in header of bb %d has non-NULL basic block", | |
2881 | INSN_UID (insn), bb->index); | |
47bd5598 | 2882 | err = true; |
251a41b9 TJ |
2883 | } |
2884 | for (insn = BB_FOOTER (bb); insn; insn = NEXT_INSN (insn)) | |
2885 | if (!BARRIER_P (insn) | |
2886 | && BLOCK_FOR_INSN (insn) != NULL) | |
2887 | { | |
2888 | error ("insn %d in footer of bb %d has non-NULL basic block", | |
2889 | INSN_UID (insn), bb->index); | |
47bd5598 | 2890 | err = true; |
251a41b9 TJ |
2891 | } |
2892 | } | |
af205f67 | 2893 | |
10e9fecc | 2894 | /* Clean up. */ |
10e9fecc JH |
2895 | return err; |
2896 | } | |
5f0d2358 | 2897 | |
10e9fecc JH |
2898 | /* Verify the CFG and RTL consistency common for both underlying RTL and |
2899 | cfglayout RTL. | |
5f0d2358 | 2900 | |
10e9fecc | 2901 | Currently it does following checks: |
251a41b9 TJ |
2902 | |
2903 | - overlapping of basic blocks | |
2904 | - insns with wrong BLOCK_FOR_INSN pointers | |
2905 | - headers of basic blocks (the NOTE_INSN_BASIC_BLOCK note) | |
2906 | - tails of basic blocks (ensure that boundary is necessary) | |
2907 | - scans body of the basic block for JUMP_INSN, CODE_LABEL | |
2908 | and NOTE_INSN_BASIC_BLOCK | |
2909 | - verify that no fall_thru edge crosses hot/cold partition boundaries | |
2910 | - verify that there are no pending RTL branch predictions | |
600b5b1d | 2911 | - verify that hot blocks are not dominated by cold blocks |
251a41b9 TJ |
2912 | |
2913 | In future it can be extended check a lot of other stuff as well | |
2914 | (reachability of basic blocks, life information, etc. etc.). */ | |
9eab6785 | 2915 | |
47bd5598 | 2916 | static bool |
251a41b9 TJ |
2917 | rtl_verify_flow_info_1 (void) |
2918 | { | |
47bd5598 | 2919 | bool err = false; |
251a41b9 | 2920 | |
47bd5598 UB |
2921 | if (rtl_verify_bb_pointers ()) |
2922 | err = true; | |
251a41b9 | 2923 | |
47bd5598 UB |
2924 | if (rtl_verify_bb_insns ()) |
2925 | err = true; | |
251a41b9 | 2926 | |
47bd5598 UB |
2927 | if (rtl_verify_edges ()) |
2928 | err = true; | |
251a41b9 | 2929 | |
251a41b9 TJ |
2930 | return err; |
2931 | } | |
2932 | ||
2933 | /* Walk the instruction chain and verify that bb head/end pointers | |
2934 | are correct, and that instructions are in exactly one bb and have | |
2935 | correct block pointers. */ | |
2936 | ||
47bd5598 | 2937 | static bool |
251a41b9 | 2938 | rtl_verify_bb_insn_chain (void) |
10e9fecc JH |
2939 | { |
2940 | basic_block bb; | |
47bd5598 | 2941 | bool err = false; |
8879d71c DM |
2942 | rtx_insn *x; |
2943 | rtx_insn *last_head = get_last_insn (); | |
9eab6785 | 2944 | basic_block *bb_info; |
9eab6785 SB |
2945 | const int max_uid = get_max_uid (); |
2946 | ||
2947 | bb_info = XCNEWVEC (basic_block, max_uid); | |
ca6c03ca | 2948 | |
4f42035e | 2949 | FOR_EACH_BB_REVERSE_FN (bb, cfun) |
10e9fecc | 2950 | { |
8879d71c DM |
2951 | rtx_insn *head = BB_HEAD (bb); |
2952 | rtx_insn *end = BB_END (bb); | |
628f6a4e | 2953 | |
9eab6785 | 2954 | for (x = last_head; x != NULL_RTX; x = PREV_INSN (x)) |
a7b87f73 ZD |
2955 | { |
2956 | /* Verify the end of the basic block is in the INSN chain. */ | |
2957 | if (x == end) | |
2958 | break; | |
2959 | ||
251a41b9 TJ |
2960 | /* And that the code outside of basic blocks has NULL bb field. */ |
2961 | if (!BARRIER_P (x) | |
2962 | && BLOCK_FOR_INSN (x) != NULL) | |
2963 | { | |
2964 | error ("insn %d outside of basic blocks has non-NULL bb field", | |
2965 | INSN_UID (x)); | |
47bd5598 | 2966 | err = true; |
251a41b9 | 2967 | } |
a7b87f73 | 2968 | } |
9eab6785 SB |
2969 | |
2970 | if (!x) | |
2971 | { | |
2972 | error ("end insn %d for block %d not found in the insn stream", | |
2973 | INSN_UID (end), bb->index); | |
47bd5598 | 2974 | err = true; |
9eab6785 SB |
2975 | } |
2976 | ||
2977 | /* Work backwards from the end to the head of the basic block | |
2978 | to verify the head is in the RTL chain. */ | |
2979 | for (; x != NULL_RTX; x = PREV_INSN (x)) | |
a00d11f0 | 2980 | { |
9eab6785 SB |
2981 | /* While walking over the insn chain, verify insns appear |
2982 | in only one basic block. */ | |
2983 | if (bb_info[INSN_UID (x)] != NULL) | |
2984 | { | |
2985 | error ("insn %d is in multiple basic blocks (%d and %d)", | |
2986 | INSN_UID (x), bb->index, bb_info[INSN_UID (x)]->index); | |
47bd5598 | 2987 | err = true; |
9eab6785 SB |
2988 | } |
2989 | ||
2990 | bb_info[INSN_UID (x)] = bb; | |
2991 | ||
2992 | if (x == head) | |
2993 | break; | |
2994 | } | |
2995 | if (!x) | |
2996 | { | |
2997 | error ("head insn %d for block %d not found in the insn stream", | |
2998 | INSN_UID (head), bb->index); | |
47bd5598 | 2999 | err = true; |
a00d11f0 JH |
3000 | } |
3001 | ||
a7b87f73 | 3002 | last_head = PREV_INSN (x); |
251a41b9 TJ |
3003 | } |
3004 | ||
3005 | for (x = last_head; x != NULL_RTX; x = PREV_INSN (x)) | |
3006 | { | |
3007 | /* Check that the code before the first basic block has NULL | |
3008 | bb field. */ | |
3009 | if (!BARRIER_P (x) | |
3010 | && BLOCK_FOR_INSN (x) != NULL) | |
3011 | { | |
3012 | error ("insn %d outside of basic blocks has non-NULL bb field", | |
3013 | INSN_UID (x)); | |
47bd5598 | 3014 | err = true; |
251a41b9 TJ |
3015 | } |
3016 | } | |
3017 | free (bb_info); | |
3018 | ||
3019 | return err; | |
3020 | } | |
3021 | ||
3022 | /* Verify that fallthru edges point to adjacent blocks in layout order and | |
3023 | that barriers exist after non-fallthru blocks. */ | |
3024 | ||
47bd5598 | 3025 | static bool |
251a41b9 TJ |
3026 | rtl_verify_fallthru (void) |
3027 | { | |
3028 | basic_block bb; | |
47bd5598 | 3029 | bool err = false; |
251a41b9 | 3030 | |
4f42035e | 3031 | FOR_EACH_BB_REVERSE_FN (bb, cfun) |
251a41b9 TJ |
3032 | { |
3033 | edge e; | |
9eab6785 | 3034 | |
0fd4b31d | 3035 | e = find_fallthru_edge (bb->succs); |
10e9fecc JH |
3036 | if (!e) |
3037 | { | |
8879d71c | 3038 | rtx_insn *insn; |
10e9fecc JH |
3039 | |
3040 | /* Ensure existence of barrier in BB with no fallthru edges. */ | |
468059bc DD |
3041 | for (insn = NEXT_INSN (BB_END (bb)); ; insn = NEXT_INSN (insn)) |
3042 | { | |
3043 | if (!insn || NOTE_INSN_BASIC_BLOCK_P (insn)) | |
10e9fecc JH |
3044 | { |
3045 | error ("missing barrier after block %i", bb->index); | |
47bd5598 | 3046 | err = true; |
10e9fecc JH |
3047 | break; |
3048 | } | |
468059bc DD |
3049 | if (BARRIER_P (insn)) |
3050 | break; | |
3051 | } | |
10e9fecc | 3052 | } |
fefa31b5 DM |
3053 | else if (e->src != ENTRY_BLOCK_PTR_FOR_FN (cfun) |
3054 | && e->dest != EXIT_BLOCK_PTR_FOR_FN (cfun)) | |
c22cacf3 | 3055 | { |
8879d71c | 3056 | rtx_insn *insn; |
10e9fecc JH |
3057 | |
3058 | if (e->src->next_bb != e->dest) | |
3059 | { | |
3060 | error | |
3061 | ("verify_flow_info: Incorrect blocks for fallthru %i->%i", | |
3062 | e->src->index, e->dest->index); | |
47bd5598 | 3063 | err = true; |
10e9fecc JH |
3064 | } |
3065 | else | |
a813c111 | 3066 | for (insn = NEXT_INSN (BB_END (e->src)); insn != BB_HEAD (e->dest); |
10e9fecc | 3067 | insn = NEXT_INSN (insn)) |
65f4b875 | 3068 | if (BARRIER_P (insn) || NONDEBUG_INSN_P (insn)) |
10e9fecc JH |
3069 | { |
3070 | error ("verify_flow_info: Incorrect fallthru %i->%i", | |
3071 | e->src->index, e->dest->index); | |
8addb0b1 RB |
3072 | error ("wrong insn in the fallthru edge"); |
3073 | debug_rtx (insn); | |
47bd5598 | 3074 | err = true; |
10e9fecc | 3075 | } |
c22cacf3 | 3076 | } |
10e9fecc | 3077 | } |
ca6c03ca | 3078 | |
251a41b9 TJ |
3079 | return err; |
3080 | } | |
3081 | ||
3082 | /* Verify that blocks are laid out in consecutive order. While walking the | |
3083 | instructions, verify that all expected instructions are inside the basic | |
3084 | blocks, and that all returns are followed by barriers. */ | |
3085 | ||
47bd5598 | 3086 | static bool |
251a41b9 TJ |
3087 | rtl_verify_bb_layout (void) |
3088 | { | |
3089 | basic_block bb; | |
47bd5598 | 3090 | bool err = false; |
65f4b875 | 3091 | rtx_insn *x, *y; |
251a41b9 | 3092 | int num_bb_notes; |
8879d71c | 3093 | rtx_insn * const rtx_first = get_insns (); |
fefa31b5 | 3094 | basic_block last_bb_seen = ENTRY_BLOCK_PTR_FOR_FN (cfun), curr_bb = NULL; |
9eab6785 | 3095 | |
ca6c03ca | 3096 | num_bb_notes = 0; |
e0082a72 | 3097 | |
5f0d2358 | 3098 | for (x = rtx_first; x; x = NEXT_INSN (x)) |
ca6c03ca JH |
3099 | { |
3100 | if (NOTE_INSN_BASIC_BLOCK_P (x)) | |
3101 | { | |
bf77398c | 3102 | bb = NOTE_BASIC_BLOCK (x); |
5f0d2358 | 3103 | |
ca6c03ca | 3104 | num_bb_notes++; |
e0082a72 | 3105 | if (bb != last_bb_seen->next_bb) |
10e9fecc | 3106 | internal_error ("basic blocks not laid down consecutively"); |
ca6c03ca | 3107 | |
10e9fecc | 3108 | curr_bb = last_bb_seen = bb; |
ca6c03ca JH |
3109 | } |
3110 | ||
10e9fecc | 3111 | if (!curr_bb) |
ca6c03ca JH |
3112 | { |
3113 | switch (GET_CODE (x)) | |
3114 | { | |
3115 | case BARRIER: | |
3116 | case NOTE: | |
3117 | break; | |
3118 | ||
3119 | case CODE_LABEL: | |
39718607 | 3120 | /* An ADDR_VEC is placed outside any basic block. */ |
ca6c03ca | 3121 | if (NEXT_INSN (x) |
481683e1 | 3122 | && JUMP_TABLE_DATA_P (NEXT_INSN (x))) |
5f0d2358 | 3123 | x = NEXT_INSN (x); |
ca6c03ca JH |
3124 | |
3125 | /* But in any case, non-deletable labels can appear anywhere. */ | |
3126 | break; | |
3127 | ||
3128 | default: | |
1f978f5f | 3129 | fatal_insn ("insn outside basic block", x); |
ca6c03ca JH |
3130 | } |
3131 | } | |
3132 | ||
26cae194 | 3133 | if (JUMP_P (x) |
ca6c03ca | 3134 | && returnjump_p (x) && ! condjump_p (x) |
65f4b875 AO |
3135 | && ! ((y = next_nonnote_nondebug_insn (x)) |
3136 | && BARRIER_P (y))) | |
1f978f5f | 3137 | fatal_insn ("return not followed by barrier", x); |
251a41b9 | 3138 | |
a813c111 | 3139 | if (curr_bb && x == BB_END (curr_bb)) |
10e9fecc | 3140 | curr_bb = NULL; |
ca6c03ca JH |
3141 | } |
3142 | ||
0cae8d31 | 3143 | if (num_bb_notes != n_basic_blocks_for_fn (cfun) - NUM_FIXED_BLOCKS) |
ca6c03ca | 3144 | internal_error |
0b17ab2f | 3145 | ("number of bb notes in insn chain (%d) != n_basic_blocks (%d)", |
0cae8d31 | 3146 | num_bb_notes, n_basic_blocks_for_fn (cfun)); |
ca6c03ca | 3147 | |
10e9fecc | 3148 | return err; |
ca6c03ca | 3149 | } |
251a41b9 TJ |
3150 | |
3151 | /* Verify the CFG and RTL consistency common for both underlying RTL and | |
3152 | cfglayout RTL, plus consistency checks specific to linearized RTL mode. | |
3153 | ||
3154 | Currently it does following checks: | |
3155 | - all checks of rtl_verify_flow_info_1 | |
3156 | - test head/end pointers | |
3157 | - check that blocks are laid out in consecutive order | |
3158 | - check that all insns are in the basic blocks | |
3159 | (except the switch handling code, barriers and notes) | |
3160 | - check that all returns are followed by barriers | |
600b5b1d TJ |
3161 | - check that all fallthru edge points to the adjacent blocks |
3162 | - verify that there is a single hot/cold partition boundary after bbro */ | |
251a41b9 | 3163 | |
47bd5598 | 3164 | static bool |
251a41b9 TJ |
3165 | rtl_verify_flow_info (void) |
3166 | { | |
47bd5598 | 3167 | bool err = false; |
251a41b9 | 3168 | |
47bd5598 UB |
3169 | if (rtl_verify_flow_info_1 ()) |
3170 | err = true; | |
251a41b9 | 3171 | |
47bd5598 UB |
3172 | if (rtl_verify_bb_insn_chain ()) |
3173 | err = true; | |
251a41b9 | 3174 | |
47bd5598 UB |
3175 | if (rtl_verify_fallthru ()) |
3176 | err = true; | |
251a41b9 | 3177 | |
47bd5598 UB |
3178 | if (rtl_verify_bb_layout ()) |
3179 | err = true; | |
251a41b9 | 3180 | |
47bd5598 UB |
3181 | if (verify_hot_cold_block_grouping ()) |
3182 | err = true; | |
3371a64f | 3183 | |
251a41b9 TJ |
3184 | return err; |
3185 | } | |
ca6c03ca | 3186 | \f |
eaec9b3d | 3187 | /* Assume that the preceding pass has possibly eliminated jump instructions |
ca6c03ca JH |
3188 | or converted the unconditional jumps. Eliminate the edges from CFG. |
3189 | Return true if any edges are eliminated. */ | |
3190 | ||
3191 | bool | |
d329e058 | 3192 | purge_dead_edges (basic_block bb) |
ca6c03ca | 3193 | { |
628f6a4e | 3194 | edge e; |
8879d71c DM |
3195 | rtx_insn *insn = BB_END (bb); |
3196 | rtx note; | |
ca6c03ca | 3197 | bool purged = false; |
628f6a4e BE |
3198 | bool found; |
3199 | edge_iterator ei; | |
ca6c03ca | 3200 | |
18edc195 | 3201 | if ((DEBUG_INSN_P (insn) || NOTE_P (insn)) && insn != BB_HEAD (bb)) |
b5b8b0ac AO |
3202 | do |
3203 | insn = PREV_INSN (insn); | |
3204 | while ((DEBUG_INSN_P (insn) || NOTE_P (insn)) && insn != BB_HEAD (bb)); | |
3205 | ||
70da1d03 | 3206 | /* If this instruction cannot trap, remove REG_EH_REGION notes. */ |
4b4bf941 | 3207 | if (NONJUMP_INSN_P (insn) |
70da1d03 JH |
3208 | && (note = find_reg_note (insn, REG_EH_REGION, NULL))) |
3209 | { | |
3210 | rtx eqnote; | |
3211 | ||
3212 | if (! may_trap_p (PATTERN (insn)) | |
3213 | || ((eqnote = find_reg_equal_equiv_note (insn)) | |
3214 | && ! may_trap_p (XEXP (eqnote, 0)))) | |
3215 | remove_note (insn, note); | |
3216 | } | |
3217 | ||
546c093e | 3218 | /* Cleanup abnormal edges caused by exceptions or non-local gotos. */ |
628f6a4e | 3219 | for (ei = ei_start (bb->succs); (e = ei_safe_edge (ei)); ) |
546c093e | 3220 | { |
1d65f45c RH |
3221 | bool remove = false; |
3222 | ||
e5f9a909 JW |
3223 | /* There are three types of edges we need to handle correctly here: EH |
3224 | edges, abnormal call EH edges, and abnormal call non-EH edges. The | |
3225 | latter can appear when nonlocal gotos are used. */ | |
1d65f45c | 3226 | if (e->flags & EDGE_ABNORMAL_CALL) |
546c093e | 3227 | { |
1d65f45c RH |
3228 | if (!CALL_P (insn)) |
3229 | remove = true; | |
3230 | else if (can_nonlocal_goto (insn)) | |
3231 | ; | |
3232 | else if ((e->flags & EDGE_EH) && can_throw_internal (insn)) | |
3233 | ; | |
0a35513e AH |
3234 | else if (flag_tm && find_reg_note (insn, REG_TM, NULL)) |
3235 | ; | |
1d65f45c RH |
3236 | else |
3237 | remove = true; | |
546c093e | 3238 | } |
1d65f45c RH |
3239 | else if (e->flags & EDGE_EH) |
3240 | remove = !can_throw_internal (insn); | |
3241 | ||
3242 | if (remove) | |
546c093e | 3243 | { |
1d65f45c RH |
3244 | remove_edge (e); |
3245 | df_set_bb_dirty (bb); | |
3246 | purged = true; | |
546c093e RH |
3247 | } |
3248 | else | |
1d65f45c | 3249 | ei_next (&ei); |
546c093e | 3250 | } |
5f0d2358 | 3251 | |
4b4bf941 | 3252 | if (JUMP_P (insn)) |
ca6c03ca JH |
3253 | { |
3254 | rtx note; | |
3255 | edge b,f; | |
628f6a4e | 3256 | edge_iterator ei; |
5f0d2358 | 3257 | |
ca6c03ca JH |
3258 | /* We do care only about conditional jumps and simplejumps. */ |
3259 | if (!any_condjump_p (insn) | |
3260 | && !returnjump_p (insn) | |
3261 | && !simplejump_p (insn)) | |
c51d95ec | 3262 | return purged; |
5f0d2358 | 3263 | |
5a1a3e5e JH |
3264 | /* Branch probability/prediction notes are defined only for |
3265 | condjumps. We've possibly turned condjump into simplejump. */ | |
3266 | if (simplejump_p (insn)) | |
3267 | { | |
3268 | note = find_reg_note (insn, REG_BR_PROB, NULL); | |
3269 | if (note) | |
3270 | remove_note (insn, note); | |
3271 | while ((note = find_reg_note (insn, REG_BR_PRED, NULL))) | |
3272 | remove_note (insn, note); | |
3273 | } | |
3274 | ||
628f6a4e | 3275 | for (ei = ei_start (bb->succs); (e = ei_safe_edge (ei)); ) |
ca6c03ca | 3276 | { |
7fcd7218 JH |
3277 | /* Avoid abnormal flags to leak from computed jumps turned |
3278 | into simplejumps. */ | |
f87c27b4 | 3279 | |
0e1638d4 | 3280 | e->flags &= ~EDGE_ABNORMAL; |
7fcd7218 | 3281 | |
5a566bed MM |
3282 | /* See if this edge is one we should keep. */ |
3283 | if ((e->flags & EDGE_FALLTHRU) && any_condjump_p (insn)) | |
3284 | /* A conditional jump can fall through into the next | |
3285 | block, so we should keep the edge. */ | |
628f6a4e BE |
3286 | { |
3287 | ei_next (&ei); | |
3288 | continue; | |
3289 | } | |
fefa31b5 | 3290 | else if (e->dest != EXIT_BLOCK_PTR_FOR_FN (cfun) |
a813c111 | 3291 | && BB_HEAD (e->dest) == JUMP_LABEL (insn)) |
5a566bed MM |
3292 | /* If the destination block is the target of the jump, |
3293 | keep the edge. */ | |
628f6a4e BE |
3294 | { |
3295 | ei_next (&ei); | |
3296 | continue; | |
3297 | } | |
fefa31b5 DM |
3298 | else if (e->dest == EXIT_BLOCK_PTR_FOR_FN (cfun) |
3299 | && returnjump_p (insn)) | |
5a566bed MM |
3300 | /* If the destination block is the exit block, and this |
3301 | instruction is a return, then keep the edge. */ | |
628f6a4e BE |
3302 | { |
3303 | ei_next (&ei); | |
3304 | continue; | |
3305 | } | |
5a566bed MM |
3306 | else if ((e->flags & EDGE_EH) && can_throw_internal (insn)) |
3307 | /* Keep the edges that correspond to exceptions thrown by | |
0b75beaa EB |
3308 | this instruction and rematerialize the EDGE_ABNORMAL |
3309 | flag we just cleared above. */ | |
3310 | { | |
3311 | e->flags |= EDGE_ABNORMAL; | |
628f6a4e | 3312 | ei_next (&ei); |
0b75beaa EB |
3313 | continue; |
3314 | } | |
5f0d2358 | 3315 | |
5a566bed | 3316 | /* We do not need this edge. */ |
6fb5fa3c | 3317 | df_set_bb_dirty (bb); |
ca6c03ca JH |
3318 | purged = true; |
3319 | remove_edge (e); | |
3320 | } | |
5f0d2358 | 3321 | |
628f6a4e | 3322 | if (EDGE_COUNT (bb->succs) == 0 || !purged) |
c51d95ec | 3323 | return purged; |
5f0d2358 | 3324 | |
c263766c RH |
3325 | if (dump_file) |
3326 | fprintf (dump_file, "Purged edges from bb %i\n", bb->index); | |
5f0d2358 | 3327 | |
ca6c03ca JH |
3328 | if (!optimize) |
3329 | return purged; | |
3330 | ||
3331 | /* Redistribute probabilities. */ | |
c5cbcccf | 3332 | if (single_succ_p (bb)) |
ca6c03ca | 3333 | { |
357067f2 | 3334 | single_succ_edge (bb)->probability = profile_probability::always (); |
f87c27b4 | 3335 | } |
ca6c03ca JH |
3336 | else |
3337 | { | |
3338 | note = find_reg_note (insn, REG_BR_PROB, NULL); | |
3339 | if (!note) | |
3340 | return purged; | |
5f0d2358 | 3341 | |
ca6c03ca JH |
3342 | b = BRANCH_EDGE (bb); |
3343 | f = FALLTHRU_EDGE (bb); | |
5fa396ad | 3344 | b->probability = profile_probability::from_reg_br_prob_note |
357067f2 | 3345 | (XINT (note, 0)); |
5fa396ad | 3346 | f->probability = b->probability.invert (); |
ca6c03ca | 3347 | } |
5f0d2358 | 3348 | |
ca6c03ca JH |
3349 | return purged; |
3350 | } | |
4b4bf941 | 3351 | else if (CALL_P (insn) && SIBLING_CALL_P (insn)) |
1722c2c8 RH |
3352 | { |
3353 | /* First, there should not be any EH or ABCALL edges resulting | |
3354 | from non-local gotos and the like. If there were, we shouldn't | |
3355 | have created the sibcall in the first place. Second, there | |
3356 | should of course never have been a fallthru edge. */ | |
c5cbcccf ZD |
3357 | gcc_assert (single_succ_p (bb)); |
3358 | gcc_assert (single_succ_edge (bb)->flags | |
3359 | == (EDGE_SIBCALL | EDGE_ABNORMAL)); | |
1722c2c8 | 3360 | |
47bd5598 | 3361 | return false; |
1722c2c8 | 3362 | } |
ca6c03ca | 3363 | |
ca6c03ca JH |
3364 | /* If we don't see a jump insn, we don't know exactly why the block would |
3365 | have been broken at this point. Look for a simple, non-fallthru edge, | |
3366 | as these are only created by conditional branches. If we find such an | |
3367 | edge we know that there used to be a jump here and can then safely | |
3368 | remove all non-fallthru edges. */ | |
628f6a4e BE |
3369 | found = false; |
3370 | FOR_EACH_EDGE (e, ei, bb->succs) | |
3371 | if (! (e->flags & (EDGE_COMPLEX | EDGE_FALLTHRU))) | |
3372 | { | |
3373 | found = true; | |
3374 | break; | |
3375 | } | |
5f0d2358 | 3376 | |
628f6a4e | 3377 | if (!found) |
ca6c03ca | 3378 | return purged; |
5f0d2358 | 3379 | |
2afa8dce DB |
3380 | /* Remove all but the fake and fallthru edges. The fake edge may be |
3381 | the only successor for this block in the case of noreturn | |
3382 | calls. */ | |
628f6a4e | 3383 | for (ei = ei_start (bb->succs); (e = ei_safe_edge (ei)); ) |
ca6c03ca | 3384 | { |
2afa8dce | 3385 | if (!(e->flags & (EDGE_FALLTHRU | EDGE_FAKE))) |
c51d95ec | 3386 | { |
6fb5fa3c | 3387 | df_set_bb_dirty (bb); |
c51d95ec JH |
3388 | remove_edge (e); |
3389 | purged = true; | |
3390 | } | |
628f6a4e BE |
3391 | else |
3392 | ei_next (&ei); | |
ca6c03ca | 3393 | } |
5f0d2358 | 3394 | |
c5cbcccf | 3395 | gcc_assert (single_succ_p (bb)); |
5f0d2358 | 3396 | |
357067f2 | 3397 | single_succ_edge (bb)->probability = profile_probability::always (); |
ca6c03ca | 3398 | |
c263766c RH |
3399 | if (dump_file) |
3400 | fprintf (dump_file, "Purged non-fallthru edges from bb %i\n", | |
0b17ab2f | 3401 | bb->index); |
ca6c03ca JH |
3402 | return purged; |
3403 | } | |
3404 | ||
5f0d2358 RK |
3405 | /* Search all basic blocks for potentially dead edges and purge them. Return |
3406 | true if some edge has been eliminated. */ | |
ca6c03ca JH |
3407 | |
3408 | bool | |
25cd19de | 3409 | purge_all_dead_edges (void) |
ca6c03ca | 3410 | { |
47bd5598 | 3411 | bool purged = false; |
e0082a72 | 3412 | basic_block bb; |
473fb060 | 3413 | |
11cd3bed | 3414 | FOR_EACH_BB_FN (bb, cfun) |
47bd5598 UB |
3415 | if (purge_dead_edges (bb)) |
3416 | purged = true; | |
5f0d2358 | 3417 | |
ca6c03ca JH |
3418 | return purged; |
3419 | } | |
9ee634e3 | 3420 | |
ba5e9aca EB |
3421 | /* This is used by a few passes that emit some instructions after abnormal |
3422 | calls, moving the basic block's end, while they in fact do want to emit | |
3423 | them on the fallthru edge. Look for abnormal call edges, find backward | |
3424 | the call in the block and insert the instructions on the edge instead. | |
3425 | ||
3426 | Similarly, handle instructions throwing exceptions internally. | |
3427 | ||
3428 | Return true when instructions have been found and inserted on edges. */ | |
3429 | ||
3430 | bool | |
3431 | fixup_abnormal_edges (void) | |
3432 | { | |
3433 | bool inserted = false; | |
3434 | basic_block bb; | |
3435 | ||
11cd3bed | 3436 | FOR_EACH_BB_FN (bb, cfun) |
ba5e9aca EB |
3437 | { |
3438 | edge e; | |
3439 | edge_iterator ei; | |
3440 | ||
3441 | /* Look for cases we are interested in - calls or instructions causing | |
3442 | exceptions. */ | |
3443 | FOR_EACH_EDGE (e, ei, bb->succs) | |
3444 | if ((e->flags & EDGE_ABNORMAL_CALL) | |
3445 | || ((e->flags & (EDGE_ABNORMAL | EDGE_EH)) | |
3446 | == (EDGE_ABNORMAL | EDGE_EH))) | |
3447 | break; | |
3448 | ||
3449 | if (e && !CALL_P (BB_END (bb)) && !can_throw_internal (BB_END (bb))) | |
3450 | { | |
8879d71c | 3451 | rtx_insn *insn; |
ba5e9aca EB |
3452 | |
3453 | /* Get past the new insns generated. Allow notes, as the insns | |
3454 | may be already deleted. */ | |
3455 | insn = BB_END (bb); | |
3456 | while ((NONJUMP_INSN_P (insn) || NOTE_P (insn)) | |
3457 | && !can_throw_internal (insn) | |
3458 | && insn != BB_HEAD (bb)) | |
3459 | insn = PREV_INSN (insn); | |
3460 | ||
3461 | if (CALL_P (insn) || can_throw_internal (insn)) | |
3462 | { | |
8879d71c | 3463 | rtx_insn *stop, *next; |
ba5e9aca EB |
3464 | |
3465 | e = find_fallthru_edge (bb->succs); | |
3466 | ||
3467 | stop = NEXT_INSN (BB_END (bb)); | |
1130d5e3 | 3468 | BB_END (bb) = insn; |
ba5e9aca EB |
3469 | |
3470 | for (insn = NEXT_INSN (insn); insn != stop; insn = next) | |
3471 | { | |
3472 | next = NEXT_INSN (insn); | |
3473 | if (INSN_P (insn)) | |
3474 | { | |
3475 | delete_insn (insn); | |
3476 | ||
3477 | /* Sometimes there's still the return value USE. | |
3478 | If it's placed after a trapping call (i.e. that | |
3479 | call is the last insn anyway), we have no fallthru | |
3480 | edge. Simply delete this use and don't try to insert | |
3df45f17 JJ |
3481 | on the non-existent edge. |
3482 | Similarly, sometimes a call that can throw is | |
3483 | followed in the source with __builtin_unreachable (), | |
3484 | meaning that there is UB if the call returns rather | |
3485 | than throws. If there weren't any instructions | |
3486 | following such calls before, supposedly even the ones | |
3487 | we've deleted aren't significant and can be | |
3488 | removed. */ | |
3489 | if (e) | |
ba5e9aca EB |
3490 | { |
3491 | /* We're not deleting it, we're moving it. */ | |
4654c0cf | 3492 | insn->set_undeleted (); |
0f82e5c9 DM |
3493 | SET_PREV_INSN (insn) = NULL_RTX; |
3494 | SET_NEXT_INSN (insn) = NULL_RTX; | |
ba5e9aca EB |
3495 | |
3496 | insert_insn_on_edge (insn, e); | |
3497 | inserted = true; | |
3498 | } | |
3499 | } | |
3500 | else if (!BARRIER_P (insn)) | |
3501 | set_block_for_insn (insn, NULL); | |
3502 | } | |
3503 | } | |
3504 | ||
3505 | /* It may be that we don't find any trapping insn. In this | |
3506 | case we discovered quite late that the insn that had been | |
3507 | marked as can_throw_internal in fact couldn't trap at all. | |
3508 | So we should in fact delete the EH edges out of the block. */ | |
3509 | else | |
3510 | purge_dead_edges (bb); | |
3511 | } | |
3512 | } | |
3513 | ||
3514 | return inserted; | |
3515 | } | |
78bde837 | 3516 | \f |
21335c48 RS |
3517 | /* Delete the unconditional jump INSN and adjust the CFG correspondingly. |
3518 | Note that the INSN should be deleted *after* removing dead edges, so | |
3519 | that the kept edge is the fallthrough edge for a (set (pc) (pc)) | |
3520 | but not for a (set (pc) (label_ref FOO)). */ | |
3521 | ||
3522 | void | |
3523 | update_cfg_for_uncondjump (rtx_insn *insn) | |
3524 | { | |
3525 | basic_block bb = BLOCK_FOR_INSN (insn); | |
3526 | gcc_assert (BB_END (bb) == insn); | |
3527 | ||
3528 | purge_dead_edges (bb); | |
3529 | ||
3530 | if (current_ir_type () != IR_RTL_CFGLAYOUT) | |
3531 | { | |
3532 | if (!find_fallthru_edge (bb->succs)) | |
3533 | { | |
3534 | auto barrier = next_nonnote_nondebug_insn (insn); | |
3535 | if (!barrier || !BARRIER_P (barrier)) | |
3536 | emit_barrier_after (insn); | |
3537 | } | |
3538 | return; | |
3539 | } | |
3540 | ||
3541 | delete_insn (insn); | |
3542 | if (EDGE_COUNT (bb->succs) == 1) | |
3543 | { | |
3544 | rtx_insn *insn; | |
3545 | ||
3546 | single_succ_edge (bb)->flags |= EDGE_FALLTHRU; | |
3547 | ||
3548 | /* Remove barriers from the footer if there are any. */ | |
3549 | for (insn = BB_FOOTER (bb); insn; insn = NEXT_INSN (insn)) | |
3550 | if (BARRIER_P (insn)) | |
3551 | { | |
3552 | if (PREV_INSN (insn)) | |
3553 | SET_NEXT_INSN (PREV_INSN (insn)) = NEXT_INSN (insn); | |
3554 | else | |
3555 | BB_FOOTER (bb) = NEXT_INSN (insn); | |
3556 | if (NEXT_INSN (insn)) | |
3557 | SET_PREV_INSN (NEXT_INSN (insn)) = PREV_INSN (insn); | |
3558 | } | |
3559 | else if (LABEL_P (insn)) | |
3560 | break; | |
3561 | } | |
3562 | } | |
3563 | \f | |
78bde837 SB |
3564 | /* Cut the insns from FIRST to LAST out of the insns stream. */ |
3565 | ||
a90c614a | 3566 | rtx_insn * |
9152e0aa | 3567 | unlink_insn_chain (rtx_insn *first, rtx_insn *last) |
78bde837 | 3568 | { |
a90c614a DM |
3569 | rtx_insn *prevfirst = PREV_INSN (first); |
3570 | rtx_insn *nextlast = NEXT_INSN (last); | |
78bde837 | 3571 | |
0f82e5c9 DM |
3572 | SET_PREV_INSN (first) = NULL; |
3573 | SET_NEXT_INSN (last) = NULL; | |
78bde837 | 3574 | if (prevfirst) |
0f82e5c9 | 3575 | SET_NEXT_INSN (prevfirst) = nextlast; |
78bde837 | 3576 | if (nextlast) |
0f82e5c9 | 3577 | SET_PREV_INSN (nextlast) = prevfirst; |
78bde837 SB |
3578 | else |
3579 | set_last_insn (prevfirst); | |
3580 | if (!prevfirst) | |
3581 | set_first_insn (nextlast); | |
9152e0aa | 3582 | return first; |
78bde837 SB |
3583 | } |
3584 | \f | |
3585 | /* Skip over inter-block insns occurring after BB which are typically | |
3586 | associated with BB (e.g., barriers). If there are any such insns, | |
3587 | we return the last one. Otherwise, we return the end of BB. */ | |
3588 | ||
8879d71c | 3589 | static rtx_insn * |
78bde837 SB |
3590 | skip_insns_after_block (basic_block bb) |
3591 | { | |
8879d71c | 3592 | rtx_insn *insn, *last_insn, *next_head, *prev; |
78bde837 | 3593 | |
8879d71c | 3594 | next_head = NULL; |
fefa31b5 | 3595 | if (bb->next_bb != EXIT_BLOCK_PTR_FOR_FN (cfun)) |
78bde837 SB |
3596 | next_head = BB_HEAD (bb->next_bb); |
3597 | ||
3598 | for (last_insn = insn = BB_END (bb); (insn = NEXT_INSN (insn)) != 0; ) | |
3599 | { | |
3600 | if (insn == next_head) | |
3601 | break; | |
3602 | ||
3603 | switch (GET_CODE (insn)) | |
3604 | { | |
3605 | case BARRIER: | |
3606 | last_insn = insn; | |
3607 | continue; | |
3608 | ||
3609 | case NOTE: | |
2acbc4eb RB |
3610 | gcc_assert (NOTE_KIND (insn) != NOTE_INSN_BLOCK_END); |
3611 | continue; | |
78bde837 SB |
3612 | |
3613 | case CODE_LABEL: | |
3614 | if (NEXT_INSN (insn) | |
3615 | && JUMP_TABLE_DATA_P (NEXT_INSN (insn))) | |
3616 | { | |
3617 | insn = NEXT_INSN (insn); | |
3618 | last_insn = insn; | |
3619 | continue; | |
3620 | } | |
3621 | break; | |
3622 | ||
3623 | default: | |
3624 | break; | |
3625 | } | |
3626 | ||
3627 | break; | |
3628 | } | |
3629 | ||
3630 | /* It is possible to hit contradictory sequence. For instance: | |
3631 | ||
3632 | jump_insn | |
3633 | NOTE_INSN_BLOCK_BEG | |
3634 | barrier | |
3635 | ||
3636 | Where barrier belongs to jump_insn, but the note does not. This can be | |
3637 | created by removing the basic block originally following | |
3638 | NOTE_INSN_BLOCK_BEG. In such case reorder the notes. */ | |
3639 | ||
3640 | for (insn = last_insn; insn != BB_END (bb); insn = prev) | |
3641 | { | |
3642 | prev = PREV_INSN (insn); | |
3643 | if (NOTE_P (insn)) | |
3644 | switch (NOTE_KIND (insn)) | |
3645 | { | |
3646 | case NOTE_INSN_BLOCK_END: | |
3647 | gcc_unreachable (); | |
3648 | break; | |
3649 | case NOTE_INSN_DELETED: | |
3650 | case NOTE_INSN_DELETED_LABEL: | |
3651 | case NOTE_INSN_DELETED_DEBUG_LABEL: | |
3652 | continue; | |
3653 | default: | |
3654 | reorder_insns (insn, insn, last_insn); | |
3655 | } | |
3656 | } | |
3657 | ||
3658 | return last_insn; | |
3659 | } | |
3660 | ||
3661 | /* Locate or create a label for a given basic block. */ | |
3662 | ||
e67d1102 | 3663 | static rtx_insn * |
78bde837 SB |
3664 | label_for_bb (basic_block bb) |
3665 | { | |
e67d1102 | 3666 | rtx_insn *label = BB_HEAD (bb); |
78bde837 SB |
3667 | |
3668 | if (!LABEL_P (label)) | |
3669 | { | |
3670 | if (dump_file) | |
3671 | fprintf (dump_file, "Emitting label for block %d\n", bb->index); | |
3672 | ||
3673 | label = block_label (bb); | |
3674 | } | |
3675 | ||
3676 | return label; | |
3677 | } | |
3678 | ||
3679 | /* Locate the effective beginning and end of the insn chain for each | |
3680 | block, as defined by skip_insns_after_block above. */ | |
3681 | ||
3682 | static void | |
3683 | record_effective_endpoints (void) | |
3684 | { | |
8879d71c | 3685 | rtx_insn *next_insn; |
78bde837 | 3686 | basic_block bb; |
8879d71c | 3687 | rtx_insn *insn; |
78bde837 SB |
3688 | |
3689 | for (insn = get_insns (); | |
3690 | insn | |
3691 | && NOTE_P (insn) | |
3692 | && NOTE_KIND (insn) != NOTE_INSN_BASIC_BLOCK; | |
3693 | insn = NEXT_INSN (insn)) | |
3694 | continue; | |
3695 | /* No basic blocks at all? */ | |
3696 | gcc_assert (insn); | |
3697 | ||
3698 | if (PREV_INSN (insn)) | |
3699 | cfg_layout_function_header = | |
3700 | unlink_insn_chain (get_insns (), PREV_INSN (insn)); | |
3701 | else | |
9152e0aa | 3702 | cfg_layout_function_header = NULL; |
78bde837 SB |
3703 | |
3704 | next_insn = get_insns (); | |
11cd3bed | 3705 | FOR_EACH_BB_FN (bb, cfun) |
78bde837 | 3706 | { |
8879d71c | 3707 | rtx_insn *end; |
78bde837 SB |
3708 | |
3709 | if (PREV_INSN (BB_HEAD (bb)) && next_insn != BB_HEAD (bb)) | |
1130d5e3 | 3710 | BB_HEADER (bb) = unlink_insn_chain (next_insn, |
190bea87 | 3711 | PREV_INSN (BB_HEAD (bb))); |
78bde837 SB |
3712 | end = skip_insns_after_block (bb); |
3713 | if (NEXT_INSN (BB_END (bb)) && BB_END (bb) != end) | |
d8ce2eae | 3714 | BB_FOOTER (bb) = unlink_insn_chain (NEXT_INSN (BB_END (bb)), end); |
78bde837 SB |
3715 | next_insn = NEXT_INSN (BB_END (bb)); |
3716 | } | |
3717 | ||
3718 | cfg_layout_function_footer = next_insn; | |
3719 | if (cfg_layout_function_footer) | |
3720 | cfg_layout_function_footer = unlink_insn_chain (cfg_layout_function_footer, get_last_insn ()); | |
3721 | } | |
3722 | \f | |
27a4cd48 DM |
3723 | namespace { |
3724 | ||
3725 | const pass_data pass_data_into_cfg_layout_mode = | |
3726 | { | |
3727 | RTL_PASS, /* type */ | |
3728 | "into_cfglayout", /* name */ | |
3729 | OPTGROUP_NONE, /* optinfo_flags */ | |
27a4cd48 DM |
3730 | TV_CFG, /* tv_id */ |
3731 | 0, /* properties_required */ | |
3732 | PROP_cfglayout, /* properties_provided */ | |
3733 | 0, /* properties_destroyed */ | |
3734 | 0, /* todo_flags_start */ | |
3735 | 0, /* todo_flags_finish */ | |
78bde837 SB |
3736 | }; |
3737 | ||
27a4cd48 DM |
3738 | class pass_into_cfg_layout_mode : public rtl_opt_pass |
3739 | { | |
3740 | public: | |
c3284718 RS |
3741 | pass_into_cfg_layout_mode (gcc::context *ctxt) |
3742 | : rtl_opt_pass (pass_data_into_cfg_layout_mode, ctxt) | |
27a4cd48 DM |
3743 | {} |
3744 | ||
3745 | /* opt_pass methods: */ | |
725793af | 3746 | unsigned int execute (function *) final override |
be55bfe6 TS |
3747 | { |
3748 | cfg_layout_initialize (0); | |
3749 | return 0; | |
3750 | } | |
27a4cd48 DM |
3751 | |
3752 | }; // class pass_into_cfg_layout_mode | |
3753 | ||
3754 | } // anon namespace | |
3755 | ||
3756 | rtl_opt_pass * | |
3757 | make_pass_into_cfg_layout_mode (gcc::context *ctxt) | |
3758 | { | |
3759 | return new pass_into_cfg_layout_mode (ctxt); | |
3760 | } | |
3761 | ||
3762 | namespace { | |
3763 | ||
3764 | const pass_data pass_data_outof_cfg_layout_mode = | |
3765 | { | |
3766 | RTL_PASS, /* type */ | |
3767 | "outof_cfglayout", /* name */ | |
3768 | OPTGROUP_NONE, /* optinfo_flags */ | |
27a4cd48 DM |
3769 | TV_CFG, /* tv_id */ |
3770 | 0, /* properties_required */ | |
3771 | 0, /* properties_provided */ | |
3772 | PROP_cfglayout, /* properties_destroyed */ | |
3773 | 0, /* todo_flags_start */ | |
3774 | 0, /* todo_flags_finish */ | |
78bde837 | 3775 | }; |
27a4cd48 DM |
3776 | |
3777 | class pass_outof_cfg_layout_mode : public rtl_opt_pass | |
3778 | { | |
3779 | public: | |
c3284718 RS |
3780 | pass_outof_cfg_layout_mode (gcc::context *ctxt) |
3781 | : rtl_opt_pass (pass_data_outof_cfg_layout_mode, ctxt) | |
27a4cd48 DM |
3782 | {} |
3783 | ||
3784 | /* opt_pass methods: */ | |
725793af | 3785 | unsigned int execute (function *) final override; |
27a4cd48 DM |
3786 | |
3787 | }; // class pass_outof_cfg_layout_mode | |
3788 | ||
be55bfe6 TS |
3789 | unsigned int |
3790 | pass_outof_cfg_layout_mode::execute (function *fun) | |
3791 | { | |
3792 | basic_block bb; | |
3793 | ||
3794 | FOR_EACH_BB_FN (bb, fun) | |
3795 | if (bb->next_bb != EXIT_BLOCK_PTR_FOR_FN (fun)) | |
3796 | bb->aux = bb->next_bb; | |
3797 | ||
3798 | cfg_layout_finalize (); | |
3799 | ||
3800 | return 0; | |
3801 | } | |
3802 | ||
27a4cd48 DM |
3803 | } // anon namespace |
3804 | ||
3805 | rtl_opt_pass * | |
3806 | make_pass_outof_cfg_layout_mode (gcc::context *ctxt) | |
3807 | { | |
3808 | return new pass_outof_cfg_layout_mode (ctxt); | |
3809 | } | |
78bde837 SB |
3810 | \f |
3811 | ||
3812 | /* Link the basic blocks in the correct order, compacting the basic | |
3813 | block queue while at it. If STAY_IN_CFGLAYOUT_MODE is false, this | |
3814 | function also clears the basic block header and footer fields. | |
3815 | ||
3816 | This function is usually called after a pass (e.g. tracer) finishes | |
3817 | some transformations while in cfglayout mode. The required sequence | |
3818 | of the basic blocks is in a linked list along the bb->aux field. | |
3819 | This functions re-links the basic block prev_bb and next_bb pointers | |
532aafad SB |
3820 | accordingly, and it compacts and renumbers the blocks. |
3821 | ||
3822 | FIXME: This currently works only for RTL, but the only RTL-specific | |
3823 | bits are the STAY_IN_CFGLAYOUT_MODE bits. The tracer pass was moved | |
3824 | to GIMPLE a long time ago, but it doesn't relink the basic block | |
3825 | chain. It could do that (to give better initial RTL) if this function | |
e53b6e56 | 3826 | is made IR-agnostic (and moved to cfganal.cc or cfg.cc while at it). */ |
78bde837 SB |
3827 | |
3828 | void | |
3829 | relink_block_chain (bool stay_in_cfglayout_mode) | |
3830 | { | |
3831 | basic_block bb, prev_bb; | |
3832 | int index; | |
3833 | ||
3834 | /* Maybe dump the re-ordered sequence. */ | |
3835 | if (dump_file) | |
3836 | { | |
3837 | fprintf (dump_file, "Reordered sequence:\n"); | |
fefa31b5 DM |
3838 | for (bb = ENTRY_BLOCK_PTR_FOR_FN (cfun)->next_bb, index = |
3839 | NUM_FIXED_BLOCKS; | |
78bde837 SB |
3840 | bb; |
3841 | bb = (basic_block) bb->aux, index++) | |
3842 | { | |
3843 | fprintf (dump_file, " %i ", index); | |
3844 | if (get_bb_original (bb)) | |
f3b4eae6 | 3845 | fprintf (dump_file, "duplicate of %i\n", |
78bde837 SB |
3846 | get_bb_original (bb)->index); |
3847 | else if (forwarder_block_p (bb) | |
3848 | && !LABEL_P (BB_HEAD (bb))) | |
f3b4eae6 | 3849 | fprintf (dump_file, "compensation\n"); |
78bde837 | 3850 | else |
f3b4eae6 | 3851 | fprintf (dump_file, "bb %i\n", bb->index); |
78bde837 SB |
3852 | } |
3853 | } | |
3854 | ||
3855 | /* Now reorder the blocks. */ | |
fefa31b5 DM |
3856 | prev_bb = ENTRY_BLOCK_PTR_FOR_FN (cfun); |
3857 | bb = ENTRY_BLOCK_PTR_FOR_FN (cfun)->next_bb; | |
78bde837 SB |
3858 | for (; bb; prev_bb = bb, bb = (basic_block) bb->aux) |
3859 | { | |
3860 | bb->prev_bb = prev_bb; | |
3861 | prev_bb->next_bb = bb; | |
3862 | } | |
fefa31b5 DM |
3863 | prev_bb->next_bb = EXIT_BLOCK_PTR_FOR_FN (cfun); |
3864 | EXIT_BLOCK_PTR_FOR_FN (cfun)->prev_bb = prev_bb; | |
78bde837 SB |
3865 | |
3866 | /* Then, clean up the aux fields. */ | |
04a90bec | 3867 | FOR_ALL_BB_FN (bb, cfun) |
78bde837 SB |
3868 | { |
3869 | bb->aux = NULL; | |
3870 | if (!stay_in_cfglayout_mode) | |
1130d5e3 | 3871 | BB_HEADER (bb) = BB_FOOTER (bb) = NULL; |
78bde837 SB |
3872 | } |
3873 | ||
3874 | /* Maybe reset the original copy tables, they are not valid anymore | |
3875 | when we renumber the basic blocks in compact_blocks. If we are | |
3876 | are going out of cfglayout mode, don't re-allocate the tables. */ | |
c2e84327 DM |
3877 | if (original_copy_tables_initialized_p ()) |
3878 | free_original_copy_tables (); | |
78bde837 SB |
3879 | if (stay_in_cfglayout_mode) |
3880 | initialize_original_copy_tables (); | |
3881 | ||
3882 | /* Finally, put basic_block_info in the new order. */ | |
3883 | compact_blocks (); | |
3884 | } | |
3885 | \f | |
3886 | ||
3887 | /* Given a reorder chain, rearrange the code to match. */ | |
3888 | ||
3889 | static void | |
3890 | fixup_reorder_chain (void) | |
3891 | { | |
3892 | basic_block bb; | |
9152e0aa | 3893 | rtx_insn *insn = NULL; |
78bde837 SB |
3894 | |
3895 | if (cfg_layout_function_header) | |
3896 | { | |
3897 | set_first_insn (cfg_layout_function_header); | |
3898 | insn = cfg_layout_function_header; | |
3899 | while (NEXT_INSN (insn)) | |
3900 | insn = NEXT_INSN (insn); | |
3901 | } | |
3902 | ||
3903 | /* First do the bulk reordering -- rechain the blocks without regard to | |
3904 | the needed changes to jumps and labels. */ | |
3905 | ||
fefa31b5 DM |
3906 | for (bb = ENTRY_BLOCK_PTR_FOR_FN (cfun)->next_bb; bb; bb = (basic_block) |
3907 | bb->aux) | |
78bde837 SB |
3908 | { |
3909 | if (BB_HEADER (bb)) | |
3910 | { | |
3911 | if (insn) | |
0f82e5c9 | 3912 | SET_NEXT_INSN (insn) = BB_HEADER (bb); |
78bde837 SB |
3913 | else |
3914 | set_first_insn (BB_HEADER (bb)); | |
0f82e5c9 | 3915 | SET_PREV_INSN (BB_HEADER (bb)) = insn; |
78bde837 SB |
3916 | insn = BB_HEADER (bb); |
3917 | while (NEXT_INSN (insn)) | |
3918 | insn = NEXT_INSN (insn); | |
3919 | } | |
3920 | if (insn) | |
0f82e5c9 | 3921 | SET_NEXT_INSN (insn) = BB_HEAD (bb); |
78bde837 SB |
3922 | else |
3923 | set_first_insn (BB_HEAD (bb)); | |
0f82e5c9 | 3924 | SET_PREV_INSN (BB_HEAD (bb)) = insn; |
78bde837 SB |
3925 | insn = BB_END (bb); |
3926 | if (BB_FOOTER (bb)) | |
3927 | { | |
0f82e5c9 DM |
3928 | SET_NEXT_INSN (insn) = BB_FOOTER (bb); |
3929 | SET_PREV_INSN (BB_FOOTER (bb)) = insn; | |
78bde837 SB |
3930 | while (NEXT_INSN (insn)) |
3931 | insn = NEXT_INSN (insn); | |
3932 | } | |
3933 | } | |
3934 | ||
0f82e5c9 | 3935 | SET_NEXT_INSN (insn) = cfg_layout_function_footer; |
78bde837 | 3936 | if (cfg_layout_function_footer) |
0f82e5c9 | 3937 | SET_PREV_INSN (cfg_layout_function_footer) = insn; |
78bde837 SB |
3938 | |
3939 | while (NEXT_INSN (insn)) | |
3940 | insn = NEXT_INSN (insn); | |
3941 | ||
3942 | set_last_insn (insn); | |
b2b29377 MM |
3943 | if (flag_checking) |
3944 | verify_insn_chain (); | |
78bde837 SB |
3945 | |
3946 | /* Now add jumps and labels as needed to match the blocks new | |
29f3fd5b | 3947 | outgoing edges. */ |
78bde837 | 3948 | |
1b74b5cb | 3949 | bool remove_unreachable_blocks = false; |
29f3fd5b SB |
3950 | for (bb = ENTRY_BLOCK_PTR_FOR_FN (cfun)->next_bb; bb ; bb = (basic_block) |
3951 | bb->aux) | |
78bde837 SB |
3952 | { |
3953 | edge e_fall, e_taken, e; | |
8879d71c | 3954 | rtx_insn *bb_end_insn; |
78bde837 | 3955 | rtx ret_label = NULL_RTX; |
3371a64f | 3956 | basic_block nb; |
78bde837 | 3957 | edge_iterator ei; |
4fb639a7 | 3958 | bool asm_goto = false; |
78bde837 SB |
3959 | |
3960 | if (EDGE_COUNT (bb->succs) == 0) | |
3961 | continue; | |
3962 | ||
3963 | /* Find the old fallthru edge, and another non-EH edge for | |
3964 | a taken jump. */ | |
3965 | e_taken = e_fall = NULL; | |
3966 | ||
3967 | FOR_EACH_EDGE (e, ei, bb->succs) | |
3968 | if (e->flags & EDGE_FALLTHRU) | |
3969 | e_fall = e; | |
3970 | else if (! (e->flags & EDGE_EH)) | |
3971 | e_taken = e; | |
3972 | ||
3973 | bb_end_insn = BB_END (bb); | |
1476d1bd | 3974 | if (rtx_jump_insn *bb_end_jump = dyn_cast <rtx_jump_insn *> (bb_end_insn)) |
78bde837 | 3975 | { |
1476d1bd MM |
3976 | ret_label = JUMP_LABEL (bb_end_jump); |
3977 | if (any_condjump_p (bb_end_jump)) | |
78bde837 SB |
3978 | { |
3979 | /* This might happen if the conditional jump has side | |
3980 | effects and could therefore not be optimized away. | |
3981 | Make the basic block to end with a barrier in order | |
3982 | to prevent rtl_verify_flow_info from complaining. */ | |
3983 | if (!e_fall) | |
3984 | { | |
1476d1bd MM |
3985 | gcc_assert (!onlyjump_p (bb_end_jump) |
3986 | || returnjump_p (bb_end_jump) | |
91af97c3 | 3987 | || (e_taken->flags & EDGE_CROSSING)); |
1476d1bd | 3988 | emit_barrier_after (bb_end_jump); |
78bde837 SB |
3989 | continue; |
3990 | } | |
3991 | ||
3992 | /* If the old fallthru is still next, nothing to do. */ | |
3993 | if (bb->aux == e_fall->dest | |
fefa31b5 | 3994 | || e_fall->dest == EXIT_BLOCK_PTR_FOR_FN (cfun)) |
78bde837 SB |
3995 | continue; |
3996 | ||
3997 | /* The degenerated case of conditional jump jumping to the next | |
3998 | instruction can happen for jumps with side effects. We need | |
3999 | to construct a forwarder block and this will be done just | |
4000 | fine by force_nonfallthru below. */ | |
4001 | if (!e_taken) | |
4002 | ; | |
4003 | ||
4004 | /* There is another special case: if *neither* block is next, | |
4005 | such as happens at the very end of a function, then we'll | |
4006 | need to add a new unconditional jump. Choose the taken | |
4007 | edge based on known or assumed probability. */ | |
4008 | else if (bb->aux != e_taken->dest) | |
4009 | { | |
1476d1bd | 4010 | rtx note = find_reg_note (bb_end_jump, REG_BR_PROB, 0); |
78bde837 SB |
4011 | |
4012 | if (note | |
5fa396ad JH |
4013 | && profile_probability::from_reg_br_prob_note |
4014 | (XINT (note, 0)) < profile_probability::even () | |
1476d1bd | 4015 | && invert_jump (bb_end_jump, |
fefa31b5 DM |
4016 | (e_fall->dest |
4017 | == EXIT_BLOCK_PTR_FOR_FN (cfun) | |
78bde837 SB |
4018 | ? NULL_RTX |
4019 | : label_for_bb (e_fall->dest)), 0)) | |
4020 | { | |
4021 | e_fall->flags &= ~EDGE_FALLTHRU; | |
4022 | gcc_checking_assert (could_fall_through | |
4023 | (e_taken->src, e_taken->dest)); | |
4024 | e_taken->flags |= EDGE_FALLTHRU; | |
4025 | update_br_prob_note (bb); | |
4026 | e = e_fall, e_fall = e_taken, e_taken = e; | |
4027 | } | |
4028 | } | |
4029 | ||
4030 | /* If the "jumping" edge is a crossing edge, and the fall | |
4031 | through edge is non-crossing, leave things as they are. */ | |
4032 | else if ((e_taken->flags & EDGE_CROSSING) | |
4033 | && !(e_fall->flags & EDGE_CROSSING)) | |
4034 | continue; | |
4035 | ||
4036 | /* Otherwise we can try to invert the jump. This will | |
4037 | basically never fail, however, keep up the pretense. */ | |
1476d1bd | 4038 | else if (invert_jump (bb_end_jump, |
fefa31b5 DM |
4039 | (e_fall->dest |
4040 | == EXIT_BLOCK_PTR_FOR_FN (cfun) | |
78bde837 SB |
4041 | ? NULL_RTX |
4042 | : label_for_bb (e_fall->dest)), 0)) | |
4043 | { | |
4044 | e_fall->flags &= ~EDGE_FALLTHRU; | |
4045 | gcc_checking_assert (could_fall_through | |
4046 | (e_taken->src, e_taken->dest)); | |
4047 | e_taken->flags |= EDGE_FALLTHRU; | |
4048 | update_br_prob_note (bb); | |
4049 | if (LABEL_NUSES (ret_label) == 0 | |
4050 | && single_pred_p (e_taken->dest)) | |
a29f6a2b | 4051 | delete_insn (as_a<rtx_insn *> (ret_label)); |
78bde837 SB |
4052 | continue; |
4053 | } | |
4054 | } | |
4055 | else if (extract_asm_operands (PATTERN (bb_end_insn)) != NULL) | |
4056 | { | |
4057 | /* If the old fallthru is still next or if | |
4058 | asm goto doesn't have a fallthru (e.g. when followed by | |
4059 | __builtin_unreachable ()), nothing to do. */ | |
4060 | if (! e_fall | |
4061 | || bb->aux == e_fall->dest | |
fefa31b5 | 4062 | || e_fall->dest == EXIT_BLOCK_PTR_FOR_FN (cfun)) |
78bde837 SB |
4063 | continue; |
4064 | ||
4fb639a7 JJ |
4065 | /* Otherwise we'll have to use the fallthru fixup below. |
4066 | But avoid redirecting asm goto to EXIT. */ | |
4067 | asm_goto = true; | |
78bde837 SB |
4068 | } |
4069 | else | |
4070 | { | |
4071 | /* Otherwise we have some return, switch or computed | |
4072 | jump. In the 99% case, there should not have been a | |
4073 | fallthru edge. */ | |
4074 | gcc_assert (returnjump_p (bb_end_insn) || !e_fall); | |
4075 | continue; | |
4076 | } | |
4077 | } | |
4078 | else | |
4079 | { | |
4080 | /* No fallthru implies a noreturn function with EH edges, or | |
4081 | something similarly bizarre. In any case, we don't need to | |
4082 | do anything. */ | |
4083 | if (! e_fall) | |
4084 | continue; | |
4085 | ||
4086 | /* If the fallthru block is still next, nothing to do. */ | |
4087 | if (bb->aux == e_fall->dest) | |
4088 | continue; | |
4089 | ||
4090 | /* A fallthru to exit block. */ | |
fefa31b5 | 4091 | if (e_fall->dest == EXIT_BLOCK_PTR_FOR_FN (cfun)) |
78bde837 SB |
4092 | continue; |
4093 | } | |
4094 | ||
1b74b5cb JL |
4095 | /* If E_FALL->dest is just a return block, then we can emit a |
4096 | return rather than a jump to the return block. */ | |
4097 | rtx_insn *ret, *use; | |
4098 | basic_block dest; | |
4fb639a7 JJ |
4099 | if (!asm_goto |
4100 | && bb_is_just_return (e_fall->dest, &ret, &use) | |
5da546d7 JL |
4101 | && ((PATTERN (ret) == simple_return_rtx && targetm.have_simple_return ()) |
4102 | || (PATTERN (ret) == ret_rtx && targetm.have_return ()))) | |
1b74b5cb JL |
4103 | { |
4104 | ret_label = PATTERN (ret); | |
4105 | dest = EXIT_BLOCK_PTR_FOR_FN (cfun); | |
4106 | ||
db24bdc7 | 4107 | e_fall->flags &= ~EDGE_CROSSING; |
1b74b5cb JL |
4108 | /* E_FALL->dest might become unreachable as a result of |
4109 | replacing the jump with a return. So arrange to remove | |
4110 | unreachable blocks. */ | |
4111 | remove_unreachable_blocks = true; | |
4112 | } | |
4113 | else | |
4114 | { | |
4115 | dest = e_fall->dest; | |
4116 | } | |
4117 | ||
78bde837 SB |
4118 | /* We got here if we need to add a new jump insn. |
4119 | Note force_nonfallthru can delete E_FALL and thus we have to | |
4120 | save E_FALL->src prior to the call to force_nonfallthru. */ | |
1b74b5cb | 4121 | nb = force_nonfallthru_and_redirect (e_fall, dest, ret_label); |
78bde837 SB |
4122 | if (nb) |
4123 | { | |
4124 | nb->aux = bb->aux; | |
4125 | bb->aux = nb; | |
4126 | /* Don't process this new block. */ | |
4127 | bb = nb; | |
78bde837 SB |
4128 | } |
4129 | } | |
4130 | ||
4131 | relink_block_chain (/*stay_in_cfglayout_mode=*/false); | |
4132 | ||
29f3fd5b | 4133 | /* Annoying special case - jump around dead jumptables left in the code. */ |
11cd3bed | 4134 | FOR_EACH_BB_FN (bb, cfun) |
78bde837 SB |
4135 | { |
4136 | edge e = find_fallthru_edge (bb->succs); | |
4137 | ||
29f3fd5b SB |
4138 | if (e && !can_fallthru (e->src, e->dest)) |
4139 | force_nonfallthru (e); | |
78bde837 SB |
4140 | } |
4141 | ||
7792f13c EB |
4142 | /* Ensure goto_locus from edges has some instructions with that locus in RTL |
4143 | when not optimizing. */ | |
4144 | if (!optimize && !DECL_IGNORED_P (current_function_decl)) | |
11cd3bed | 4145 | FOR_EACH_BB_FN (bb, cfun) |
78bde837 SB |
4146 | { |
4147 | edge e; | |
4148 | edge_iterator ei; | |
4149 | ||
4150 | FOR_EACH_EDGE (e, ei, bb->succs) | |
2f13f2de | 4151 | if (LOCATION_LOCUS (e->goto_locus) != UNKNOWN_LOCATION |
5368224f | 4152 | && !(e->flags & EDGE_ABNORMAL)) |
78bde837 SB |
4153 | { |
4154 | edge e2; | |
4155 | edge_iterator ei2; | |
4156 | basic_block dest, nb; | |
8879d71c | 4157 | rtx_insn *end; |
78bde837 SB |
4158 | |
4159 | insn = BB_END (e->src); | |
4160 | end = PREV_INSN (BB_HEAD (e->src)); | |
4161 | while (insn != end | |
5368224f | 4162 | && (!NONDEBUG_INSN_P (insn) || !INSN_HAS_LOCATION (insn))) |
78bde837 SB |
4163 | insn = PREV_INSN (insn); |
4164 | if (insn != end | |
2e1b0036 | 4165 | && loc_equal (INSN_LOCATION (insn), e->goto_locus)) |
78bde837 SB |
4166 | continue; |
4167 | if (simplejump_p (BB_END (e->src)) | |
5368224f | 4168 | && !INSN_HAS_LOCATION (BB_END (e->src))) |
78bde837 | 4169 | { |
5368224f | 4170 | INSN_LOCATION (BB_END (e->src)) = e->goto_locus; |
78bde837 SB |
4171 | continue; |
4172 | } | |
4173 | dest = e->dest; | |
fefa31b5 | 4174 | if (dest == EXIT_BLOCK_PTR_FOR_FN (cfun)) |
78bde837 SB |
4175 | { |
4176 | /* Non-fallthru edges to the exit block cannot be split. */ | |
4177 | if (!(e->flags & EDGE_FALLTHRU)) | |
4178 | continue; | |
4179 | } | |
4180 | else | |
4181 | { | |
4182 | insn = BB_HEAD (dest); | |
4183 | end = NEXT_INSN (BB_END (dest)); | |
4184 | while (insn != end && !NONDEBUG_INSN_P (insn)) | |
4185 | insn = NEXT_INSN (insn); | |
5368224f | 4186 | if (insn != end && INSN_HAS_LOCATION (insn) |
2e1b0036 | 4187 | && loc_equal (INSN_LOCATION (insn), e->goto_locus)) |
78bde837 SB |
4188 | continue; |
4189 | } | |
4190 | nb = split_edge (e); | |
4191 | if (!INSN_P (BB_END (nb))) | |
1130d5e3 | 4192 | BB_END (nb) = emit_insn_after_noloc (gen_nop (), BB_END (nb), |
190bea87 | 4193 | nb); |
5368224f | 4194 | INSN_LOCATION (BB_END (nb)) = e->goto_locus; |
78bde837 SB |
4195 | |
4196 | /* If there are other incoming edges to the destination block | |
4197 | with the same goto locus, redirect them to the new block as | |
4198 | well, this can prevent other such blocks from being created | |
4199 | in subsequent iterations of the loop. */ | |
4200 | for (ei2 = ei_start (dest->preds); (e2 = ei_safe_edge (ei2)); ) | |
2f13f2de | 4201 | if (LOCATION_LOCUS (e2->goto_locus) != UNKNOWN_LOCATION |
78bde837 | 4202 | && !(e2->flags & (EDGE_ABNORMAL | EDGE_FALLTHRU)) |
5368224f | 4203 | && e->goto_locus == e2->goto_locus) |
78bde837 SB |
4204 | redirect_edge_and_branch (e2, nb); |
4205 | else | |
4206 | ei_next (&ei2); | |
4207 | } | |
4208 | } | |
1b74b5cb JL |
4209 | |
4210 | /* Replacing a jump with a return may have exposed an unreachable | |
4211 | block. Conditionally remove them if such transformations were | |
4212 | made. */ | |
4213 | if (remove_unreachable_blocks) | |
4214 | delete_unreachable_blocks (); | |
78bde837 SB |
4215 | } |
4216 | \f | |
4217 | /* Perform sanity checks on the insn chain. | |
4218 | 1. Check that next/prev pointers are consistent in both the forward and | |
4219 | reverse direction. | |
4220 | 2. Count insns in chain, going both directions, and check if equal. | |
4221 | 3. Check that get_last_insn () returns the actual end of chain. */ | |
4222 | ||
4223 | DEBUG_FUNCTION void | |
4224 | verify_insn_chain (void) | |
4225 | { | |
8879d71c | 4226 | rtx_insn *x, *prevx, *nextx; |
78bde837 SB |
4227 | int insn_cnt1, insn_cnt2; |
4228 | ||
4229 | for (prevx = NULL, insn_cnt1 = 1, x = get_insns (); | |
4230 | x != 0; | |
4231 | prevx = x, insn_cnt1++, x = NEXT_INSN (x)) | |
4232 | gcc_assert (PREV_INSN (x) == prevx); | |
4233 | ||
4234 | gcc_assert (prevx == get_last_insn ()); | |
4235 | ||
4236 | for (nextx = NULL, insn_cnt2 = 1, x = get_last_insn (); | |
4237 | x != 0; | |
4238 | nextx = x, insn_cnt2++, x = PREV_INSN (x)) | |
4239 | gcc_assert (NEXT_INSN (x) == nextx); | |
4240 | ||
4241 | gcc_assert (insn_cnt1 == insn_cnt2); | |
4242 | } | |
4243 | \f | |
4244 | /* If we have assembler epilogues, the block falling through to exit must | |
4245 | be the last one in the reordered chain when we reach final. Ensure | |
4246 | that this condition is met. */ | |
4247 | static void | |
4248 | fixup_fallthru_exit_predecessor (void) | |
4249 | { | |
4250 | edge e; | |
4251 | basic_block bb = NULL; | |
4252 | ||
4253 | /* This transformation is not valid before reload, because we might | |
4254 | separate a call from the instruction that copies the return | |
4255 | value. */ | |
4256 | gcc_assert (reload_completed); | |
4257 | ||
fefa31b5 | 4258 | e = find_fallthru_edge (EXIT_BLOCK_PTR_FOR_FN (cfun)->preds); |
78bde837 SB |
4259 | if (e) |
4260 | bb = e->src; | |
4261 | ||
4262 | if (bb && bb->aux) | |
4263 | { | |
fefa31b5 | 4264 | basic_block c = ENTRY_BLOCK_PTR_FOR_FN (cfun)->next_bb; |
78bde837 SB |
4265 | |
4266 | /* If the very first block is the one with the fall-through exit | |
4267 | edge, we have to split that block. */ | |
4268 | if (c == bb) | |
4269 | { | |
c4d281b2 | 4270 | bb = split_block_after_labels (bb)->dest; |
78bde837 SB |
4271 | bb->aux = c->aux; |
4272 | c->aux = bb; | |
d8ce2eae DM |
4273 | BB_FOOTER (bb) = BB_FOOTER (c); |
4274 | BB_FOOTER (c) = NULL; | |
78bde837 SB |
4275 | } |
4276 | ||
4277 | while (c->aux != bb) | |
4278 | c = (basic_block) c->aux; | |
4279 | ||
4280 | c->aux = bb->aux; | |
4281 | while (c->aux) | |
4282 | c = (basic_block) c->aux; | |
4283 | ||
4284 | c->aux = bb; | |
4285 | bb->aux = NULL; | |
4286 | } | |
4287 | } | |
4288 | ||
4289 | /* In case there are more than one fallthru predecessors of exit, force that | |
4290 | there is only one. */ | |
4291 | ||
4292 | static void | |
4293 | force_one_exit_fallthru (void) | |
4294 | { | |
4295 | edge e, predecessor = NULL; | |
4296 | bool more = false; | |
4297 | edge_iterator ei; | |
4298 | basic_block forwarder, bb; | |
4299 | ||
fefa31b5 | 4300 | FOR_EACH_EDGE (e, ei, EXIT_BLOCK_PTR_FOR_FN (cfun)->preds) |
78bde837 SB |
4301 | if (e->flags & EDGE_FALLTHRU) |
4302 | { | |
4303 | if (predecessor == NULL) | |
4304 | predecessor = e; | |
4305 | else | |
4306 | { | |
4307 | more = true; | |
4308 | break; | |
4309 | } | |
4310 | } | |
4311 | ||
4312 | if (!more) | |
4313 | return; | |
4314 | ||
4315 | /* Exit has several fallthru predecessors. Create a forwarder block for | |
4316 | them. */ | |
4317 | forwarder = split_edge (predecessor); | |
fefa31b5 DM |
4318 | for (ei = ei_start (EXIT_BLOCK_PTR_FOR_FN (cfun)->preds); |
4319 | (e = ei_safe_edge (ei)); ) | |
78bde837 SB |
4320 | { |
4321 | if (e->src == forwarder | |
4322 | || !(e->flags & EDGE_FALLTHRU)) | |
4323 | ei_next (&ei); | |
4324 | else | |
4325 | redirect_edge_and_branch_force (e, forwarder); | |
4326 | } | |
4327 | ||
4328 | /* Fix up the chain of blocks -- make FORWARDER immediately precede the | |
4329 | exit block. */ | |
11cd3bed | 4330 | FOR_EACH_BB_FN (bb, cfun) |
78bde837 SB |
4331 | { |
4332 | if (bb->aux == NULL && bb != forwarder) | |
4333 | { | |
4334 | bb->aux = forwarder; | |
4335 | break; | |
4336 | } | |
4337 | } | |
4338 | } | |
4339 | \f | |
4340 | /* Return true in case it is possible to duplicate the basic block BB. */ | |
4341 | ||
4342 | static bool | |
4343 | cfg_layout_can_duplicate_bb_p (const_basic_block bb) | |
4344 | { | |
4345 | /* Do not attempt to duplicate tablejumps, as we need to unshare | |
4346 | the dispatch table. This is difficult to do, as the instructions | |
4347 | computing jump destination may be hoisted outside the basic block. */ | |
4348 | if (tablejump_p (BB_END (bb), NULL, NULL)) | |
4349 | return false; | |
4350 | ||
4351 | /* Do not duplicate blocks containing insns that can't be copied. */ | |
4352 | if (targetm.cannot_copy_insn_p) | |
4353 | { | |
8879d71c | 4354 | rtx_insn *insn = BB_HEAD (bb); |
78bde837 SB |
4355 | while (1) |
4356 | { | |
4357 | if (INSN_P (insn) && targetm.cannot_copy_insn_p (insn)) | |
4358 | return false; | |
4359 | if (insn == BB_END (bb)) | |
4360 | break; | |
4361 | insn = NEXT_INSN (insn); | |
4362 | } | |
4363 | } | |
4364 | ||
4365 | return true; | |
4366 | } | |
4367 | ||
a90c614a | 4368 | rtx_insn * |
d6a05b49 RB |
4369 | duplicate_insn_chain (rtx_insn *from, rtx_insn *to, |
4370 | class loop *loop, copy_bb_data *id) | |
78bde837 | 4371 | { |
5d34b050 | 4372 | rtx_insn *insn, *next, *copy; |
66e8df53 | 4373 | rtx_note *last; |
78bde837 SB |
4374 | |
4375 | /* Avoid updating of boundaries of previous basic block. The | |
4376 | note will get removed from insn stream in fixup. */ | |
4377 | last = emit_note (NOTE_INSN_DELETED); | |
4378 | ||
4379 | /* Create copy at the end of INSN chain. The chain will | |
4380 | be reordered later. */ | |
4381 | for (insn = from; insn != NEXT_INSN (to); insn = NEXT_INSN (insn)) | |
4382 | { | |
4383 | switch (GET_CODE (insn)) | |
4384 | { | |
4385 | case DEBUG_INSN: | |
4386 | /* Don't duplicate label debug insns. */ | |
65f4b875 AO |
4387 | if (DEBUG_BIND_INSN_P (insn) |
4388 | && TREE_CODE (INSN_VAR_LOCATION_DECL (insn)) == LABEL_DECL) | |
78bde837 SB |
4389 | break; |
4390 | /* FALLTHRU */ | |
4391 | case INSN: | |
4392 | case CALL_INSN: | |
4393 | case JUMP_INSN: | |
78bde837 SB |
4394 | copy = emit_copy_of_insn_after (insn, get_last_insn ()); |
4395 | if (JUMP_P (insn) && JUMP_LABEL (insn) != NULL_RTX | |
4396 | && ANY_RETURN_P (JUMP_LABEL (insn))) | |
4397 | JUMP_LABEL (copy) = JUMP_LABEL (insn); | |
4398 | maybe_copy_prologue_epilogue_insn (insn, copy); | |
d6a05b49 RB |
4399 | /* If requested remap dependence info of cliques brought in |
4400 | via inlining. */ | |
4401 | if (id) | |
4402 | { | |
4403 | subrtx_iterator::array_type array; | |
4404 | FOR_EACH_SUBRTX (iter, array, PATTERN (insn), ALL) | |
4405 | if (MEM_P (*iter) && MEM_EXPR (*iter)) | |
4406 | { | |
4407 | tree op = MEM_EXPR (*iter); | |
4408 | if (TREE_CODE (op) == WITH_SIZE_EXPR) | |
4409 | op = TREE_OPERAND (op, 0); | |
4410 | while (handled_component_p (op)) | |
4411 | op = TREE_OPERAND (op, 0); | |
4412 | if ((TREE_CODE (op) == MEM_REF | |
4413 | || TREE_CODE (op) == TARGET_MEM_REF) | |
4414 | && MR_DEPENDENCE_CLIQUE (op) > 1 | |
4415 | && (!loop | |
4416 | || (MR_DEPENDENCE_CLIQUE (op) | |
4417 | != loop->owned_clique))) | |
4418 | { | |
4419 | if (!id->dependence_map) | |
4420 | id->dependence_map = new hash_map<dependence_hash, | |
4421 | unsigned short>; | |
4422 | bool existed; | |
4423 | unsigned short &newc = id->dependence_map->get_or_insert | |
4424 | (MR_DEPENDENCE_CLIQUE (op), &existed); | |
4425 | if (!existed) | |
4426 | { | |
4427 | gcc_assert | |
4428 | (MR_DEPENDENCE_CLIQUE (op) <= cfun->last_clique); | |
0c2ea80a | 4429 | newc = get_new_clique (cfun); |
d6a05b49 RB |
4430 | } |
4431 | /* We cannot adjust MR_DEPENDENCE_CLIQUE in-place | |
4432 | since MEM_EXPR is shared so make a copy and | |
4433 | walk to the subtree again. */ | |
4434 | tree new_expr = unshare_expr (MEM_EXPR (*iter)); | |
4435 | if (TREE_CODE (new_expr) == WITH_SIZE_EXPR) | |
4436 | new_expr = TREE_OPERAND (new_expr, 0); | |
4437 | while (handled_component_p (new_expr)) | |
4438 | new_expr = TREE_OPERAND (new_expr, 0); | |
4439 | MR_DEPENDENCE_CLIQUE (new_expr) = newc; | |
4440 | set_mem_expr (const_cast <rtx> (*iter), new_expr); | |
4441 | } | |
4442 | } | |
4443 | } | |
78bde837 SB |
4444 | break; |
4445 | ||
39718607 SB |
4446 | case JUMP_TABLE_DATA: |
4447 | /* Avoid copying of dispatch tables. We never duplicate | |
4448 | tablejumps, so this can hit only in case the table got | |
4449 | moved far from original jump. | |
4450 | Avoid copying following barrier as well if any | |
4451 | (and debug insns in between). */ | |
4452 | for (next = NEXT_INSN (insn); | |
4453 | next != NEXT_INSN (to); | |
4454 | next = NEXT_INSN (next)) | |
4455 | if (!DEBUG_INSN_P (next)) | |
4456 | break; | |
4457 | if (next != NEXT_INSN (to) && BARRIER_P (next)) | |
4458 | insn = next; | |
4459 | break; | |
4460 | ||
78bde837 SB |
4461 | case CODE_LABEL: |
4462 | break; | |
4463 | ||
4464 | case BARRIER: | |
4465 | emit_barrier (); | |
4466 | break; | |
4467 | ||
4468 | case NOTE: | |
4469 | switch (NOTE_KIND (insn)) | |
4470 | { | |
4471 | /* In case prologue is empty and function contain label | |
4472 | in first BB, we may want to copy the block. */ | |
4473 | case NOTE_INSN_PROLOGUE_END: | |
4474 | ||
4475 | case NOTE_INSN_DELETED: | |
4476 | case NOTE_INSN_DELETED_LABEL: | |
4477 | case NOTE_INSN_DELETED_DEBUG_LABEL: | |
4478 | /* No problem to strip these. */ | |
4479 | case NOTE_INSN_FUNCTION_BEG: | |
4480 | /* There is always just single entry to function. */ | |
4481 | case NOTE_INSN_BASIC_BLOCK: | |
3371a64f TJ |
4482 | /* We should only switch text sections once. */ |
4483 | case NOTE_INSN_SWITCH_TEXT_SECTIONS: | |
78bde837 SB |
4484 | break; |
4485 | ||
4486 | case NOTE_INSN_EPILOGUE_BEG: | |
d33606c3 | 4487 | case NOTE_INSN_UPDATE_SJLJ_CONTEXT: |
66e8df53 | 4488 | emit_note_copy (as_a <rtx_note *> (insn)); |
78bde837 SB |
4489 | break; |
4490 | ||
4491 | default: | |
4492 | /* All other notes should have already been eliminated. */ | |
4493 | gcc_unreachable (); | |
4494 | } | |
4495 | break; | |
4496 | default: | |
4497 | gcc_unreachable (); | |
4498 | } | |
4499 | } | |
4500 | insn = NEXT_INSN (last); | |
4501 | delete_insn (last); | |
5d34b050 | 4502 | return insn; |
78bde837 SB |
4503 | } |
4504 | ||
4505 | /* Create a duplicate of the basic block BB. */ | |
4506 | ||
4507 | static basic_block | |
d6a05b49 | 4508 | cfg_layout_duplicate_bb (basic_block bb, copy_bb_data *id) |
78bde837 | 4509 | { |
8879d71c | 4510 | rtx_insn *insn; |
78bde837 SB |
4511 | basic_block new_bb; |
4512 | ||
d6a05b49 RB |
4513 | class loop *loop = (id && current_loops) ? bb->loop_father : NULL; |
4514 | ||
4515 | insn = duplicate_insn_chain (BB_HEAD (bb), BB_END (bb), loop, id); | |
78bde837 SB |
4516 | new_bb = create_basic_block (insn, |
4517 | insn ? get_last_insn () : NULL, | |
fefa31b5 | 4518 | EXIT_BLOCK_PTR_FOR_FN (cfun)->prev_bb); |
78bde837 SB |
4519 | |
4520 | BB_COPY_PARTITION (new_bb, bb); | |
4521 | if (BB_HEADER (bb)) | |
4522 | { | |
4523 | insn = BB_HEADER (bb); | |
4524 | while (NEXT_INSN (insn)) | |
4525 | insn = NEXT_INSN (insn); | |
d6a05b49 | 4526 | insn = duplicate_insn_chain (BB_HEADER (bb), insn, loop, id); |
78bde837 | 4527 | if (insn) |
1130d5e3 | 4528 | BB_HEADER (new_bb) = unlink_insn_chain (insn, get_last_insn ()); |
78bde837 SB |
4529 | } |
4530 | ||
4531 | if (BB_FOOTER (bb)) | |
4532 | { | |
4533 | insn = BB_FOOTER (bb); | |
4534 | while (NEXT_INSN (insn)) | |
4535 | insn = NEXT_INSN (insn); | |
d6a05b49 | 4536 | insn = duplicate_insn_chain (BB_FOOTER (bb), insn, loop, id); |
78bde837 | 4537 | if (insn) |
d8ce2eae | 4538 | BB_FOOTER (new_bb) = unlink_insn_chain (insn, get_last_insn ()); |
78bde837 SB |
4539 | } |
4540 | ||
4541 | return new_bb; | |
4542 | } | |
4543 | ||
4544 | \f | |
4545 | /* Main entry point to this module - initialize the datastructures for | |
4546 | CFG layout changes. It keeps LOOPS up-to-date if not null. | |
4547 | ||
4548 | FLAGS is a set of additional flags to pass to cleanup_cfg(). */ | |
4549 | ||
4550 | void | |
1a817418 | 4551 | cfg_layout_initialize (int flags) |
78bde837 | 4552 | { |
b5241a5a | 4553 | rtx_insn_list *x; |
78bde837 SB |
4554 | basic_block bb; |
4555 | ||
8a9e6b45 BS |
4556 | /* Once bb partitioning is complete, cfg layout mode should not be |
4557 | re-entered. Entering cfg layout mode may require fixups. As an | |
4558 | example, if edge forwarding performed when optimizing the cfg | |
4559 | layout required moving a block from the hot to the cold | |
4560 | section. This would create an illegal partitioning unless some | |
4561 | manual fixup was performed. */ | |
0b6bc904 | 4562 | gcc_assert (!crtl->bb_reorder_complete || !crtl->has_bb_partition); |
4ca19309 | 4563 | |
78bde837 SB |
4564 | initialize_original_copy_tables (); |
4565 | ||
4566 | cfg_layout_rtl_register_cfg_hooks (); | |
4567 | ||
4568 | record_effective_endpoints (); | |
4569 | ||
4570 | /* Make sure that the targets of non local gotos are marked. */ | |
2382940b | 4571 | for (x = nonlocal_goto_handler_labels; x; x = x->next ()) |
78bde837 | 4572 | { |
b5241a5a | 4573 | bb = BLOCK_FOR_INSN (x->insn ()); |
78bde837 SB |
4574 | bb->flags |= BB_NON_LOCAL_GOTO_TARGET; |
4575 | } | |
4576 | ||
4577 | cleanup_cfg (CLEANUP_CFGLAYOUT | flags); | |
4578 | } | |
4579 | ||
4580 | /* Splits superblocks. */ | |
4581 | void | |
4582 | break_superblocks (void) | |
4583 | { | |
78bde837 SB |
4584 | bool need = false; |
4585 | basic_block bb; | |
4586 | ||
7ba9e72d | 4587 | auto_sbitmap superblocks (last_basic_block_for_fn (cfun)); |
f61e445a | 4588 | bitmap_clear (superblocks); |
78bde837 | 4589 | |
11cd3bed | 4590 | FOR_EACH_BB_FN (bb, cfun) |
78bde837 SB |
4591 | if (bb->flags & BB_SUPERBLOCK) |
4592 | { | |
4593 | bb->flags &= ~BB_SUPERBLOCK; | |
d7c028c0 | 4594 | bitmap_set_bit (superblocks, bb->index); |
78bde837 SB |
4595 | need = true; |
4596 | } | |
4597 | ||
4598 | if (need) | |
4599 | { | |
4600 | rebuild_jump_labels (get_insns ()); | |
4601 | find_many_sub_basic_blocks (superblocks); | |
4602 | } | |
78bde837 SB |
4603 | } |
4604 | ||
4605 | /* Finalize the changes: reorder insn list according to the sequence specified | |
29f3fd5b | 4606 | by aux pointers, enter compensation code, rebuild scope forest. */ |
78bde837 SB |
4607 | |
4608 | void | |
4609 | cfg_layout_finalize (void) | |
4610 | { | |
63da5ff6 | 4611 | free_dominance_info (CDI_DOMINATORS); |
78bde837 SB |
4612 | force_one_exit_fallthru (); |
4613 | rtl_register_cfg_hooks (); | |
e86a9946 | 4614 | if (reload_completed && !targetm.have_epilogue ()) |
78bde837 SB |
4615 | fixup_fallthru_exit_predecessor (); |
4616 | fixup_reorder_chain (); | |
4617 | ||
29f3fd5b SB |
4618 | rebuild_jump_labels (get_insns ()); |
4619 | delete_dead_jumptables (); | |
4620 | ||
b2b29377 MM |
4621 | if (flag_checking) |
4622 | verify_insn_chain (); | |
4623 | checking_verify_flow_info (); | |
78bde837 SB |
4624 | } |
4625 | ||
ba5e9aca | 4626 | |
9ee634e3 | 4627 | /* Same as split_block but update cfg_layout structures. */ |
f470c378 ZD |
4628 | |
4629 | static basic_block | |
d329e058 | 4630 | cfg_layout_split_block (basic_block bb, void *insnp) |
9ee634e3 | 4631 | { |
ae50c0cb | 4632 | rtx insn = (rtx) insnp; |
f470c378 | 4633 | basic_block new_bb = rtl_split_block (bb, insn); |
9ee634e3 | 4634 | |
d8ce2eae DM |
4635 | BB_FOOTER (new_bb) = BB_FOOTER (bb); |
4636 | BB_FOOTER (bb) = NULL; | |
9ee634e3 | 4637 | |
f470c378 | 4638 | return new_bb; |
9ee634e3 JH |
4639 | } |
4640 | ||
9ee634e3 | 4641 | /* Redirect Edge to DEST. */ |
6de9cd9a | 4642 | static edge |
d329e058 | 4643 | cfg_layout_redirect_edge_and_branch (edge e, basic_block dest) |
9ee634e3 JH |
4644 | { |
4645 | basic_block src = e->src; | |
6de9cd9a | 4646 | edge ret; |
9ee634e3 | 4647 | |
bc35512f | 4648 | if (e->flags & (EDGE_ABNORMAL_CALL | EDGE_EH)) |
6de9cd9a | 4649 | return NULL; |
bc35512f | 4650 | |
3348b696 | 4651 | if (e->dest == dest) |
6de9cd9a | 4652 | return e; |
bc35512f | 4653 | |
687d5dfe JH |
4654 | if (e->flags & EDGE_CROSSING |
4655 | && BB_PARTITION (e->src) == BB_PARTITION (dest) | |
4656 | && simplejump_p (BB_END (src))) | |
4657 | { | |
4658 | if (dump_file) | |
4659 | fprintf (dump_file, | |
4660 | "Removing crossing jump while redirecting edge form %i to %i\n", | |
4661 | e->src->index, dest->index); | |
4662 | delete_insn (BB_END (src)); | |
91c50487 | 4663 | remove_barriers_from_footer (src); |
687d5dfe JH |
4664 | e->flags |= EDGE_FALLTHRU; |
4665 | } | |
4666 | ||
fefa31b5 | 4667 | if (e->src != ENTRY_BLOCK_PTR_FOR_FN (cfun) |
6de9cd9a | 4668 | && (ret = try_redirect_by_replacing_jump (e, dest, true))) |
f345f21a | 4669 | { |
6fb5fa3c | 4670 | df_set_bb_dirty (src); |
6de9cd9a | 4671 | return ret; |
f345f21a | 4672 | } |
bc35512f | 4673 | |
fefa31b5 | 4674 | if (e->src == ENTRY_BLOCK_PTR_FOR_FN (cfun) |
bc35512f JH |
4675 | && (e->flags & EDGE_FALLTHRU) && !(e->flags & EDGE_COMPLEX)) |
4676 | { | |
c263766c RH |
4677 | if (dump_file) |
4678 | fprintf (dump_file, "Redirecting entry edge from bb %i to %i\n", | |
bc35512f JH |
4679 | e->src->index, dest->index); |
4680 | ||
6fb5fa3c | 4681 | df_set_bb_dirty (e->src); |
bc35512f | 4682 | redirect_edge_succ (e, dest); |
6de9cd9a | 4683 | return e; |
bc35512f JH |
4684 | } |
4685 | ||
9ee634e3 JH |
4686 | /* Redirect_edge_and_branch may decide to turn branch into fallthru edge |
4687 | in the case the basic block appears to be in sequence. Avoid this | |
4688 | transformation. */ | |
4689 | ||
9ee634e3 JH |
4690 | if (e->flags & EDGE_FALLTHRU) |
4691 | { | |
4692 | /* Redirect any branch edges unified with the fallthru one. */ | |
4b4bf941 | 4693 | if (JUMP_P (BB_END (src)) |
432f982f JH |
4694 | && label_is_jump_target_p (BB_HEAD (e->dest), |
4695 | BB_END (src))) | |
9ee634e3 | 4696 | { |
341c100f | 4697 | edge redirected; |
c22cacf3 | 4698 | |
c263766c RH |
4699 | if (dump_file) |
4700 | fprintf (dump_file, "Fallthru edge unified with branch " | |
432f982f JH |
4701 | "%i->%i redirected to %i\n", |
4702 | e->src->index, e->dest->index, dest->index); | |
4703 | e->flags &= ~EDGE_FALLTHRU; | |
341c100f NS |
4704 | redirected = redirect_branch_edge (e, dest); |
4705 | gcc_assert (redirected); | |
0c617be4 JL |
4706 | redirected->flags |= EDGE_FALLTHRU; |
4707 | df_set_bb_dirty (redirected->src); | |
4708 | return redirected; | |
9ee634e3 JH |
4709 | } |
4710 | /* In case we are redirecting fallthru edge to the branch edge | |
c22cacf3 | 4711 | of conditional jump, remove it. */ |
628f6a4e | 4712 | if (EDGE_COUNT (src->succs) == 2) |
9ee634e3 | 4713 | { |
03101c6f KH |
4714 | /* Find the edge that is different from E. */ |
4715 | edge s = EDGE_SUCC (src, EDGE_SUCC (src, 0) == e); | |
628f6a4e | 4716 | |
9ee634e3 | 4717 | if (s->dest == dest |
a813c111 SB |
4718 | && any_condjump_p (BB_END (src)) |
4719 | && onlyjump_p (BB_END (src))) | |
4720 | delete_insn (BB_END (src)); | |
9ee634e3 | 4721 | } |
c263766c | 4722 | if (dump_file) |
dc764d10 | 4723 | fprintf (dump_file, "Redirecting fallthru edge %i->%i to %i\n", |
bc35512f | 4724 | e->src->index, e->dest->index, dest->index); |
0c617be4 | 4725 | ret = redirect_edge_succ_nodup (e, dest); |
9ee634e3 JH |
4726 | } |
4727 | else | |
bc35512f | 4728 | ret = redirect_branch_edge (e, dest); |
9ee634e3 | 4729 | |
a09ad347 JJ |
4730 | if (!ret) |
4731 | return NULL; | |
4732 | ||
687d5dfe | 4733 | fixup_partition_crossing (ret); |
9ee634e3 | 4734 | /* We don't want simplejumps in the insn stream during cfglayout. */ |
687d5dfe | 4735 | gcc_assert (!simplejump_p (BB_END (src)) || CROSSING_JUMP_P (BB_END (src))); |
9ee634e3 | 4736 | |
6fb5fa3c | 4737 | df_set_bb_dirty (src); |
9ee634e3 JH |
4738 | return ret; |
4739 | } | |
4740 | ||
4741 | /* Simple wrapper as we always can redirect fallthru edges. */ | |
4742 | static basic_block | |
d329e058 | 4743 | cfg_layout_redirect_edge_and_branch_force (edge e, basic_block dest) |
9ee634e3 | 4744 | { |
341c100f NS |
4745 | edge redirected = cfg_layout_redirect_edge_and_branch (e, dest); |
4746 | ||
4747 | gcc_assert (redirected); | |
9ee634e3 JH |
4748 | return NULL; |
4749 | } | |
4750 | ||
f470c378 ZD |
4751 | /* Same as delete_basic_block but update cfg_layout structures. */ |
4752 | ||
9ee634e3 | 4753 | static void |
d329e058 | 4754 | cfg_layout_delete_block (basic_block bb) |
9ee634e3 | 4755 | { |
8879d71c | 4756 | rtx_insn *insn, *next, *prev = PREV_INSN (BB_HEAD (bb)), *remaints; |
1130d5e3 | 4757 | rtx_insn **to; |
9ee634e3 | 4758 | |
bcc708fc | 4759 | if (BB_HEADER (bb)) |
9ee634e3 | 4760 | { |
a813c111 | 4761 | next = BB_HEAD (bb); |
9ee634e3 | 4762 | if (prev) |
0f82e5c9 | 4763 | SET_NEXT_INSN (prev) = BB_HEADER (bb); |
9ee634e3 | 4764 | else |
bcc708fc | 4765 | set_first_insn (BB_HEADER (bb)); |
0f82e5c9 | 4766 | SET_PREV_INSN (BB_HEADER (bb)) = prev; |
bcc708fc | 4767 | insn = BB_HEADER (bb); |
9ee634e3 JH |
4768 | while (NEXT_INSN (insn)) |
4769 | insn = NEXT_INSN (insn); | |
0f82e5c9 DM |
4770 | SET_NEXT_INSN (insn) = next; |
4771 | SET_PREV_INSN (next) = insn; | |
9ee634e3 | 4772 | } |
a813c111 | 4773 | next = NEXT_INSN (BB_END (bb)); |
bcc708fc | 4774 | if (BB_FOOTER (bb)) |
9ee634e3 | 4775 | { |
bcc708fc | 4776 | insn = BB_FOOTER (bb); |
bc35512f JH |
4777 | while (insn) |
4778 | { | |
4b4bf941 | 4779 | if (BARRIER_P (insn)) |
bc35512f JH |
4780 | { |
4781 | if (PREV_INSN (insn)) | |
0f82e5c9 | 4782 | SET_NEXT_INSN (PREV_INSN (insn)) = NEXT_INSN (insn); |
bc35512f | 4783 | else |
d8ce2eae | 4784 | BB_FOOTER (bb) = NEXT_INSN (insn); |
bc35512f | 4785 | if (NEXT_INSN (insn)) |
0f82e5c9 | 4786 | SET_PREV_INSN (NEXT_INSN (insn)) = PREV_INSN (insn); |
bc35512f | 4787 | } |
4b4bf941 | 4788 | if (LABEL_P (insn)) |
bc35512f JH |
4789 | break; |
4790 | insn = NEXT_INSN (insn); | |
4791 | } | |
bcc708fc | 4792 | if (BB_FOOTER (bb)) |
bc35512f | 4793 | { |
a813c111 | 4794 | insn = BB_END (bb); |
0f82e5c9 DM |
4795 | SET_NEXT_INSN (insn) = BB_FOOTER (bb); |
4796 | SET_PREV_INSN (BB_FOOTER (bb)) = insn; | |
bc35512f JH |
4797 | while (NEXT_INSN (insn)) |
4798 | insn = NEXT_INSN (insn); | |
0f82e5c9 | 4799 | SET_NEXT_INSN (insn) = next; |
bc35512f | 4800 | if (next) |
0f82e5c9 | 4801 | SET_PREV_INSN (next) = insn; |
bc35512f JH |
4802 | else |
4803 | set_last_insn (insn); | |
4804 | } | |
9ee634e3 | 4805 | } |
fefa31b5 | 4806 | if (bb->next_bb != EXIT_BLOCK_PTR_FOR_FN (cfun)) |
1130d5e3 | 4807 | to = &BB_HEADER (bb->next_bb); |
9ee634e3 JH |
4808 | else |
4809 | to = &cfg_layout_function_footer; | |
997de8ed | 4810 | |
9ee634e3 JH |
4811 | rtl_delete_block (bb); |
4812 | ||
4813 | if (prev) | |
4814 | prev = NEXT_INSN (prev); | |
d329e058 | 4815 | else |
9ee634e3 JH |
4816 | prev = get_insns (); |
4817 | if (next) | |
4818 | next = PREV_INSN (next); | |
d329e058 | 4819 | else |
9ee634e3 JH |
4820 | next = get_last_insn (); |
4821 | ||
4822 | if (next && NEXT_INSN (next) != prev) | |
4823 | { | |
4824 | remaints = unlink_insn_chain (prev, next); | |
4825 | insn = remaints; | |
4826 | while (NEXT_INSN (insn)) | |
4827 | insn = NEXT_INSN (insn); | |
0f82e5c9 | 4828 | SET_NEXT_INSN (insn) = *to; |
9ee634e3 | 4829 | if (*to) |
0f82e5c9 | 4830 | SET_PREV_INSN (*to) = insn; |
9ee634e3 JH |
4831 | *to = remaints; |
4832 | } | |
4833 | } | |
4834 | ||
beb235f8 | 4835 | /* Return true when blocks A and B can be safely merged. */ |
b48d0358 | 4836 | |
bc35512f | 4837 | static bool |
b48d0358 | 4838 | cfg_layout_can_merge_blocks_p (basic_block a, basic_block b) |
bc35512f | 4839 | { |
750054a2 CT |
4840 | /* If we are partitioning hot/cold basic blocks, we don't want to |
4841 | mess up unconditional or indirect jumps that cross between hot | |
076c7ab8 ZW |
4842 | and cold sections. |
4843 | ||
8e8d5162 | 4844 | Basic block partitioning may result in some jumps that appear to |
c22cacf3 MS |
4845 | be optimizable (or blocks that appear to be mergeable), but which really |
4846 | must be left untouched (they are required to make it safely across | |
4847 | partition boundaries). See the comments at the top of | |
e53b6e56 | 4848 | bb-reorder.cc:partition_hot_cold_basic_blocks for complete details. */ |
8e8d5162 | 4849 | |
87c8b4be | 4850 | if (BB_PARTITION (a) != BB_PARTITION (b)) |
076c7ab8 | 4851 | return false; |
750054a2 | 4852 | |
7d776ee2 RG |
4853 | /* Protect the loop latches. */ |
4854 | if (current_loops && b->loop_father->latch == b) | |
4855 | return false; | |
4856 | ||
894a84b5 BS |
4857 | /* If we would end up moving B's instructions, make sure it doesn't fall |
4858 | through into the exit block, since we cannot recover from a fallthrough | |
4859 | edge into the exit block occurring in the middle of a function. */ | |
4860 | if (NEXT_INSN (BB_END (a)) != BB_HEAD (b)) | |
4861 | { | |
4862 | edge e = find_fallthru_edge (b->succs); | |
fefa31b5 | 4863 | if (e && e->dest == EXIT_BLOCK_PTR_FOR_FN (cfun)) |
894a84b5 BS |
4864 | return false; |
4865 | } | |
4866 | ||
bc35512f | 4867 | /* There must be exactly one edge in between the blocks. */ |
c5cbcccf ZD |
4868 | return (single_succ_p (a) |
4869 | && single_succ (a) == b | |
4870 | && single_pred_p (b) == 1 | |
628f6a4e | 4871 | && a != b |
bc35512f | 4872 | /* Must be simple edge. */ |
c5cbcccf | 4873 | && !(single_succ_edge (a)->flags & EDGE_COMPLEX) |
fefa31b5 DM |
4874 | && a != ENTRY_BLOCK_PTR_FOR_FN (cfun) |
4875 | && b != EXIT_BLOCK_PTR_FOR_FN (cfun) | |
49ea3702 SB |
4876 | /* If the jump insn has side effects, we can't kill the edge. |
4877 | When not optimizing, try_redirect_by_replacing_jump will | |
4878 | not allow us to redirect an edge by replacing a table jump. */ | |
4b4bf941 | 4879 | && (!JUMP_P (BB_END (a)) |
49ea3702 | 4880 | || ((!optimize || reload_completed) |
a813c111 | 4881 | ? simplejump_p (BB_END (a)) : onlyjump_p (BB_END (a))))); |
bc35512f JH |
4882 | } |
4883 | ||
41806d92 NS |
4884 | /* Merge block A and B. The blocks must be mergeable. */ |
4885 | ||
bc35512f JH |
4886 | static void |
4887 | cfg_layout_merge_blocks (basic_block a, basic_block b) | |
4888 | { | |
7792f13c EB |
4889 | /* If B is a forwarder block whose outgoing edge has no location, we'll |
4890 | propagate the locus of the edge between A and B onto it. */ | |
4891 | const bool forward_edge_locus | |
4892 | = (b->flags & BB_FORWARDER_BLOCK) != 0 | |
4893 | && LOCATION_LOCUS (EDGE_SUCC (b, 0)->goto_locus) == UNKNOWN_LOCATION; | |
8879d71c | 4894 | rtx_insn *insn; |
50a36e42 | 4895 | |
77a74ed7 | 4896 | gcc_checking_assert (cfg_layout_can_merge_blocks_p (a, b)); |
bc35512f | 4897 | |
6fb5fa3c | 4898 | if (dump_file) |
50a36e42 EB |
4899 | fprintf (dump_file, "Merging block %d into block %d...\n", b->index, |
4900 | a->index); | |
6fb5fa3c | 4901 | |
bc35512f | 4902 | /* If there was a CODE_LABEL beginning B, delete it. */ |
4b4bf941 | 4903 | if (LABEL_P (BB_HEAD (b))) |
2c97f8e4 | 4904 | { |
2c97f8e4 RH |
4905 | delete_insn (BB_HEAD (b)); |
4906 | } | |
bc35512f JH |
4907 | |
4908 | /* We should have fallthru edge in a, or we can do dummy redirection to get | |
4909 | it cleaned up. */ | |
4b4bf941 | 4910 | if (JUMP_P (BB_END (a))) |
628f6a4e | 4911 | try_redirect_by_replacing_jump (EDGE_SUCC (a, 0), b, true); |
341c100f | 4912 | gcc_assert (!JUMP_P (BB_END (a))); |
bc35512f | 4913 | |
7792f13c EB |
4914 | /* If not optimizing, preserve the locus of the single edge between |
4915 | blocks A and B if necessary by emitting a nop. */ | |
4916 | if (!optimize | |
4917 | && !forward_edge_locus | |
4918 | && !DECL_IGNORED_P (current_function_decl)) | |
9be94227 | 4919 | emit_nop_for_unique_locus_between (a, b); |
7241571e | 4920 | |
4c8af858 SB |
4921 | /* Move things from b->footer after a->footer. */ |
4922 | if (BB_FOOTER (b)) | |
bc35512f | 4923 | { |
4c8af858 | 4924 | if (!BB_FOOTER (a)) |
d8ce2eae | 4925 | BB_FOOTER (a) = BB_FOOTER (b); |
4c8af858 SB |
4926 | else |
4927 | { | |
8879d71c | 4928 | rtx_insn *last = BB_FOOTER (a); |
4c8af858 SB |
4929 | |
4930 | while (NEXT_INSN (last)) | |
4931 | last = NEXT_INSN (last); | |
0f82e5c9 DM |
4932 | SET_NEXT_INSN (last) = BB_FOOTER (b); |
4933 | SET_PREV_INSN (BB_FOOTER (b)) = last; | |
4c8af858 | 4934 | } |
d8ce2eae | 4935 | BB_FOOTER (b) = NULL; |
4c8af858 SB |
4936 | } |
4937 | ||
4938 | /* Move things from b->header before a->footer. | |
4939 | Note that this may include dead tablejump data, but we don't clean | |
4940 | those up until we go out of cfglayout mode. */ | |
4941 | if (BB_HEADER (b)) | |
4942 | { | |
4943 | if (! BB_FOOTER (a)) | |
d8ce2eae | 4944 | BB_FOOTER (a) = BB_HEADER (b); |
4c8af858 SB |
4945 | else |
4946 | { | |
8879d71c | 4947 | rtx_insn *last = BB_HEADER (b); |
4c8af858 SB |
4948 | |
4949 | while (NEXT_INSN (last)) | |
4950 | last = NEXT_INSN (last); | |
0f82e5c9 DM |
4951 | SET_NEXT_INSN (last) = BB_FOOTER (a); |
4952 | SET_PREV_INSN (BB_FOOTER (a)) = last; | |
d8ce2eae | 4953 | BB_FOOTER (a) = BB_HEADER (b); |
4c8af858 | 4954 | } |
1130d5e3 | 4955 | BB_HEADER (b) = NULL; |
bc35512f JH |
4956 | } |
4957 | ||
4958 | /* In the case basic blocks are not adjacent, move them around. */ | |
a813c111 | 4959 | if (NEXT_INSN (BB_END (a)) != BB_HEAD (b)) |
bc35512f | 4960 | { |
f9df6f16 | 4961 | insn = unlink_insn_chain (BB_HEAD (b), BB_END (b)); |
6c3d0e31 | 4962 | |
f9df6f16 | 4963 | emit_insn_after_noloc (insn, BB_END (a), a); |
bc35512f JH |
4964 | } |
4965 | /* Otherwise just re-associate the instructions. */ | |
4966 | else | |
4967 | { | |
a813c111 | 4968 | insn = BB_HEAD (b); |
1130d5e3 | 4969 | BB_END (a) = BB_END (b); |
bc35512f JH |
4970 | } |
4971 | ||
f9df6f16 JJ |
4972 | /* emit_insn_after_noloc doesn't call df_insn_change_bb. |
4973 | We need to explicitly call. */ | |
4974 | update_bb_for_insn_chain (insn, BB_END (b), a); | |
4975 | ||
4976 | /* Skip possible DELETED_LABEL insn. */ | |
4977 | if (!NOTE_INSN_BASIC_BLOCK_P (insn)) | |
4978 | insn = NEXT_INSN (insn); | |
4979 | gcc_assert (NOTE_INSN_BASIC_BLOCK_P (insn)); | |
1130d5e3 | 4980 | BB_HEAD (b) = BB_END (b) = NULL; |
f9df6f16 JJ |
4981 | delete_insn (insn); |
4982 | ||
6fb5fa3c DB |
4983 | df_bb_delete (b->index); |
4984 | ||
7792f13c | 4985 | if (forward_edge_locus) |
50a36e42 EB |
4986 | EDGE_SUCC (b, 0)->goto_locus = EDGE_SUCC (a, 0)->goto_locus; |
4987 | ||
c263766c | 4988 | if (dump_file) |
50a36e42 | 4989 | fprintf (dump_file, "Merged blocks %d and %d.\n", a->index, b->index); |
bc35512f JH |
4990 | } |
4991 | ||
4992 | /* Split edge E. */ | |
f470c378 | 4993 | |
bc35512f JH |
4994 | static basic_block |
4995 | cfg_layout_split_edge (edge e) | |
4996 | { | |
bc35512f | 4997 | basic_block new_bb = |
fefa31b5 | 4998 | create_basic_block (e->src != ENTRY_BLOCK_PTR_FOR_FN (cfun) |
a813c111 | 4999 | ? NEXT_INSN (BB_END (e->src)) : get_insns (), |
bc35512f JH |
5000 | NULL_RTX, e->src); |
5001 | ||
fefa31b5 | 5002 | if (e->dest == EXIT_BLOCK_PTR_FOR_FN (cfun)) |
3e7eb734 JJ |
5003 | BB_COPY_PARTITION (new_bb, e->src); |
5004 | else | |
5005 | BB_COPY_PARTITION (new_bb, e->dest); | |
a9b2ee88 | 5006 | make_edge (new_bb, e->dest, EDGE_FALLTHRU); |
bc35512f JH |
5007 | redirect_edge_and_branch_force (e, new_bb); |
5008 | ||
5009 | return new_bb; | |
5010 | } | |
5011 | ||
f470c378 ZD |
5012 | /* Do postprocessing after making a forwarder block joined by edge FALLTHRU. */ |
5013 | ||
5014 | static void | |
5015 | rtl_make_forwarder_block (edge fallthru ATTRIBUTE_UNUSED) | |
5016 | { | |
5017 | } | |
5018 | ||
df92c640 SB |
5019 | /* Return true if BB contains only labels or non-executable |
5020 | instructions. */ | |
5021 | ||
5022 | static bool | |
5023 | rtl_block_empty_p (basic_block bb) | |
5024 | { | |
8879d71c | 5025 | rtx_insn *insn; |
df92c640 | 5026 | |
fefa31b5 DM |
5027 | if (bb == ENTRY_BLOCK_PTR_FOR_FN (cfun) |
5028 | || bb == EXIT_BLOCK_PTR_FOR_FN (cfun)) | |
df92c640 SB |
5029 | return true; |
5030 | ||
5031 | FOR_BB_INSNS (bb, insn) | |
64880a7c MR |
5032 | if (NONDEBUG_INSN_P (insn) |
5033 | && (!any_uncondjump_p (insn) || !onlyjump_p (insn))) | |
df92c640 SB |
5034 | return false; |
5035 | ||
5036 | return true; | |
5037 | } | |
5038 | ||
5039 | /* Split a basic block if it ends with a conditional branch and if | |
5040 | the other part of the block is not empty. */ | |
5041 | ||
5042 | static basic_block | |
5043 | rtl_split_block_before_cond_jump (basic_block bb) | |
5044 | { | |
8879d71c DM |
5045 | rtx_insn *insn; |
5046 | rtx_insn *split_point = NULL; | |
5047 | rtx_insn *last = NULL; | |
df92c640 SB |
5048 | bool found_code = false; |
5049 | ||
5050 | FOR_BB_INSNS (bb, insn) | |
5051 | { | |
5052 | if (any_condjump_p (insn)) | |
5053 | split_point = last; | |
5054 | else if (NONDEBUG_INSN_P (insn)) | |
5055 | found_code = true; | |
5056 | last = insn; | |
5057 | } | |
5058 | ||
5059 | /* Did not find everything. */ | |
5060 | if (found_code && split_point) | |
5061 | return split_block (bb, split_point)->dest; | |
5062 | else | |
5063 | return NULL; | |
5064 | } | |
5065 | ||
47bd5598 UB |
5066 | /* Return true if BB ends with a call, possibly followed by some |
5067 | instructions that must stay with the call, false otherwise. */ | |
6de9cd9a DN |
5068 | |
5069 | static bool | |
b48d0358 | 5070 | rtl_block_ends_with_call_p (basic_block bb) |
6de9cd9a | 5071 | { |
8879d71c | 5072 | rtx_insn *insn = BB_END (bb); |
6de9cd9a | 5073 | |
4b4bf941 | 5074 | while (!CALL_P (insn) |
6de9cd9a | 5075 | && insn != BB_HEAD (bb) |
92ddef69 | 5076 | && (keep_with_call_p (insn) |
b5b8b0ac AO |
5077 | || NOTE_P (insn) |
5078 | || DEBUG_INSN_P (insn))) | |
6de9cd9a | 5079 | insn = PREV_INSN (insn); |
4b4bf941 | 5080 | return (CALL_P (insn)); |
6de9cd9a DN |
5081 | } |
5082 | ||
47bd5598 | 5083 | /* Return true if BB ends with a conditional branch, false otherwise. */ |
6de9cd9a DN |
5084 | |
5085 | static bool | |
9678086d | 5086 | rtl_block_ends_with_condjump_p (const_basic_block bb) |
6de9cd9a DN |
5087 | { |
5088 | return any_condjump_p (BB_END (bb)); | |
5089 | } | |
5090 | ||
5091 | /* Return true if we need to add fake edge to exit. | |
5092 | Helper function for rtl_flow_call_edges_add. */ | |
5093 | ||
5094 | static bool | |
8879d71c | 5095 | need_fake_edge_p (const rtx_insn *insn) |
6de9cd9a DN |
5096 | { |
5097 | if (!INSN_P (insn)) | |
5098 | return false; | |
5099 | ||
4b4bf941 | 5100 | if ((CALL_P (insn) |
6de9cd9a DN |
5101 | && !SIBLING_CALL_P (insn) |
5102 | && !find_reg_note (insn, REG_NORETURN, NULL) | |
becfd6e5 | 5103 | && !(RTL_CONST_OR_PURE_CALL_P (insn)))) |
6de9cd9a DN |
5104 | return true; |
5105 | ||
5106 | return ((GET_CODE (PATTERN (insn)) == ASM_OPERANDS | |
5107 | && MEM_VOLATILE_P (PATTERN (insn))) | |
5108 | || (GET_CODE (PATTERN (insn)) == PARALLEL | |
5109 | && asm_noperands (insn) != -1 | |
5110 | && MEM_VOLATILE_P (XVECEXP (PATTERN (insn), 0, 0))) | |
5111 | || GET_CODE (PATTERN (insn)) == ASM_INPUT); | |
5112 | } | |
5113 | ||
5114 | /* Add fake edges to the function exit for any non constant and non noreturn | |
5115 | calls, volatile inline assembly in the bitmap of blocks specified by | |
5116 | BLOCKS or to the whole CFG if BLOCKS is zero. Return the number of blocks | |
5117 | that were split. | |
5118 | ||
5119 | The goal is to expose cases in which entering a basic block does not imply | |
5120 | that all subsequent instructions must be executed. */ | |
5121 | ||
5122 | static int | |
5123 | rtl_flow_call_edges_add (sbitmap blocks) | |
5124 | { | |
5125 | int i; | |
5126 | int blocks_split = 0; | |
8b1c6fd7 | 5127 | int last_bb = last_basic_block_for_fn (cfun); |
6de9cd9a DN |
5128 | bool check_last_block = false; |
5129 | ||
0cae8d31 | 5130 | if (n_basic_blocks_for_fn (cfun) == NUM_FIXED_BLOCKS) |
6de9cd9a DN |
5131 | return 0; |
5132 | ||
5133 | if (! blocks) | |
5134 | check_last_block = true; | |
5135 | else | |
fefa31b5 DM |
5136 | check_last_block = bitmap_bit_p (blocks, |
5137 | EXIT_BLOCK_PTR_FOR_FN (cfun)->prev_bb->index); | |
6de9cd9a DN |
5138 | |
5139 | /* In the last basic block, before epilogue generation, there will be | |
5140 | a fallthru edge to EXIT. Special care is required if the last insn | |
5141 | of the last basic block is a call because make_edge folds duplicate | |
5142 | edges, which would result in the fallthru edge also being marked | |
5143 | fake, which would result in the fallthru edge being removed by | |
5144 | remove_fake_edges, which would result in an invalid CFG. | |
5145 | ||
5146 | Moreover, we can't elide the outgoing fake edge, since the block | |
5147 | profiler needs to take this into account in order to solve the minimal | |
5148 | spanning tree in the case that the call doesn't return. | |
5149 | ||
5150 | Handle this by adding a dummy instruction in a new last basic block. */ | |
5151 | if (check_last_block) | |
5152 | { | |
fefa31b5 | 5153 | basic_block bb = EXIT_BLOCK_PTR_FOR_FN (cfun)->prev_bb; |
8879d71c | 5154 | rtx_insn *insn = BB_END (bb); |
6de9cd9a DN |
5155 | |
5156 | /* Back up past insns that must be kept in the same block as a call. */ | |
5157 | while (insn != BB_HEAD (bb) | |
5158 | && keep_with_call_p (insn)) | |
5159 | insn = PREV_INSN (insn); | |
5160 | ||
5161 | if (need_fake_edge_p (insn)) | |
5162 | { | |
5163 | edge e; | |
5164 | ||
fefa31b5 | 5165 | e = find_edge (bb, EXIT_BLOCK_PTR_FOR_FN (cfun)); |
9ff3d2de JL |
5166 | if (e) |
5167 | { | |
c41c1387 | 5168 | insert_insn_on_edge (gen_use (const0_rtx), e); |
9ff3d2de JL |
5169 | commit_edge_insertions (); |
5170 | } | |
6de9cd9a DN |
5171 | } |
5172 | } | |
5173 | ||
5174 | /* Now add fake edges to the function exit for any non constant | |
5175 | calls since there is no way that we can determine if they will | |
5176 | return or not... */ | |
5177 | ||
24bd1a0b | 5178 | for (i = NUM_FIXED_BLOCKS; i < last_bb; i++) |
6de9cd9a | 5179 | { |
06e28de2 | 5180 | basic_block bb = BASIC_BLOCK_FOR_FN (cfun, i); |
8879d71c DM |
5181 | rtx_insn *insn; |
5182 | rtx_insn *prev_insn; | |
6de9cd9a DN |
5183 | |
5184 | if (!bb) | |
5185 | continue; | |
5186 | ||
d7c028c0 | 5187 | if (blocks && !bitmap_bit_p (blocks, i)) |
6de9cd9a DN |
5188 | continue; |
5189 | ||
5190 | for (insn = BB_END (bb); ; insn = prev_insn) | |
5191 | { | |
5192 | prev_insn = PREV_INSN (insn); | |
5193 | if (need_fake_edge_p (insn)) | |
5194 | { | |
5195 | edge e; | |
8879d71c | 5196 | rtx_insn *split_at_insn = insn; |
6de9cd9a DN |
5197 | |
5198 | /* Don't split the block between a call and an insn that should | |
c22cacf3 | 5199 | remain in the same block as the call. */ |
4b4bf941 | 5200 | if (CALL_P (insn)) |
6de9cd9a DN |
5201 | while (split_at_insn != BB_END (bb) |
5202 | && keep_with_call_p (NEXT_INSN (split_at_insn))) | |
5203 | split_at_insn = NEXT_INSN (split_at_insn); | |
5204 | ||
5205 | /* The handling above of the final block before the epilogue | |
c22cacf3 | 5206 | should be enough to verify that there is no edge to the exit |
6de9cd9a DN |
5207 | block in CFG already. Calling make_edge in such case would |
5208 | cause us to mark that edge as fake and remove it later. */ | |
5209 | ||
b2b29377 | 5210 | if (flag_checking && split_at_insn == BB_END (bb)) |
628f6a4e | 5211 | { |
fefa31b5 | 5212 | e = find_edge (bb, EXIT_BLOCK_PTR_FOR_FN (cfun)); |
9ff3d2de | 5213 | gcc_assert (e == NULL); |
628f6a4e | 5214 | } |
6de9cd9a DN |
5215 | |
5216 | /* Note that the following may create a new basic block | |
5217 | and renumber the existing basic blocks. */ | |
5218 | if (split_at_insn != BB_END (bb)) | |
5219 | { | |
5220 | e = split_block (bb, split_at_insn); | |
5221 | if (e) | |
5222 | blocks_split++; | |
5223 | } | |
5224 | ||
36d95aa8 JH |
5225 | edge ne = make_edge (bb, EXIT_BLOCK_PTR_FOR_FN (cfun), EDGE_FAKE); |
5226 | ne->probability = profile_probability::guessed_never (); | |
6de9cd9a DN |
5227 | } |
5228 | ||
5229 | if (insn == BB_HEAD (bb)) | |
5230 | break; | |
5231 | } | |
5232 | } | |
5233 | ||
5234 | if (blocks_split) | |
5235 | verify_flow_info (); | |
5236 | ||
5237 | return blocks_split; | |
5238 | } | |
5239 | ||
1cb7dfc3 | 5240 | /* Add COMP_RTX as a condition at end of COND_BB. FIRST_HEAD is |
315682fb | 5241 | the conditional branch target, SECOND_HEAD should be the fall-thru |
1cb7dfc3 MH |
5242 | there is no need to handle this here the loop versioning code handles |
5243 | this. the reason for SECON_HEAD is that it is needed for condition | |
5244 | in trees, and this should be of the same type since it is a hook. */ | |
5245 | static void | |
5246 | rtl_lv_add_condition_to_bb (basic_block first_head , | |
c22cacf3 MS |
5247 | basic_block second_head ATTRIBUTE_UNUSED, |
5248 | basic_block cond_bb, void *comp_rtx) | |
1cb7dfc3 | 5249 | { |
1476d1bd | 5250 | rtx_code_label *label; |
8879d71c | 5251 | rtx_insn *seq, *jump; |
1cb7dfc3 MH |
5252 | rtx op0 = XEXP ((rtx)comp_rtx, 0); |
5253 | rtx op1 = XEXP ((rtx)comp_rtx, 1); | |
5254 | enum rtx_code comp = GET_CODE ((rtx)comp_rtx); | |
ef4bddc2 | 5255 | machine_mode mode; |
1cb7dfc3 MH |
5256 | |
5257 | ||
5258 | label = block_label (first_head); | |
5259 | mode = GET_MODE (op0); | |
5260 | if (mode == VOIDmode) | |
5261 | mode = GET_MODE (op1); | |
5262 | ||
5263 | start_sequence (); | |
5264 | op0 = force_operand (op0, NULL_RTX); | |
5265 | op1 = force_operand (op1, NULL_RTX); | |
357067f2 JH |
5266 | do_compare_rtx_and_jump (op0, op1, comp, 0, mode, NULL_RTX, NULL, label, |
5267 | profile_probability::uninitialized ()); | |
1cb7dfc3 MH |
5268 | jump = get_last_insn (); |
5269 | JUMP_LABEL (jump) = label; | |
5270 | LABEL_NUSES (label)++; | |
5271 | seq = get_insns (); | |
5272 | end_sequence (); | |
5273 | ||
2b9c63a2 | 5274 | /* Add the new cond, in the new head. */ |
c3284718 | 5275 | emit_insn_after (seq, BB_END (cond_bb)); |
1cb7dfc3 MH |
5276 | } |
5277 | ||
5278 | ||
5279 | /* Given a block B with unconditional branch at its end, get the | |
5280 | store the return the branch edge and the fall-thru edge in | |
5281 | BRANCH_EDGE and FALLTHRU_EDGE respectively. */ | |
5282 | static void | |
5283 | rtl_extract_cond_bb_edges (basic_block b, edge *branch_edge, | |
5284 | edge *fallthru_edge) | |
5285 | { | |
5286 | edge e = EDGE_SUCC (b, 0); | |
5287 | ||
5288 | if (e->flags & EDGE_FALLTHRU) | |
5289 | { | |
5290 | *fallthru_edge = e; | |
5291 | *branch_edge = EDGE_SUCC (b, 1); | |
5292 | } | |
5293 | else | |
5294 | { | |
5295 | *branch_edge = e; | |
5296 | *fallthru_edge = EDGE_SUCC (b, 1); | |
5297 | } | |
5298 | } | |
5299 | ||
5e2d947c JH |
5300 | void |
5301 | init_rtl_bb_info (basic_block bb) | |
5302 | { | |
bcc708fc MM |
5303 | gcc_assert (!bb->il.x.rtl); |
5304 | bb->il.x.head_ = NULL; | |
766090c2 | 5305 | bb->il.x.rtl = ggc_cleared_alloc<rtl_bb_info> (); |
5e2d947c JH |
5306 | } |
5307 | ||
4380d5ae IL |
5308 | static bool |
5309 | rtl_bb_info_initialized_p (basic_block bb) | |
5310 | { | |
5311 | return bb->il.x.rtl; | |
5312 | } | |
5313 | ||
14fa2cc0 ZD |
5314 | /* Returns true if it is possible to remove edge E by redirecting |
5315 | it to the destination of the other edge from E->src. */ | |
5316 | ||
5317 | static bool | |
9678086d | 5318 | rtl_can_remove_branch_p (const_edge e) |
14fa2cc0 | 5319 | { |
9678086d KG |
5320 | const_basic_block src = e->src; |
5321 | const_basic_block target = EDGE_SUCC (src, EDGE_SUCC (src, 0) == e)->dest; | |
8879d71c DM |
5322 | const rtx_insn *insn = BB_END (src); |
5323 | rtx set; | |
14fa2cc0 ZD |
5324 | |
5325 | /* The conditions are taken from try_redirect_by_replacing_jump. */ | |
fefa31b5 | 5326 | if (target == EXIT_BLOCK_PTR_FOR_FN (cfun)) |
14fa2cc0 ZD |
5327 | return false; |
5328 | ||
5329 | if (e->flags & (EDGE_ABNORMAL_CALL | EDGE_EH)) | |
5330 | return false; | |
5331 | ||
3371a64f | 5332 | if (BB_PARTITION (src) != BB_PARTITION (target)) |
14fa2cc0 ZD |
5333 | return false; |
5334 | ||
5335 | if (!onlyjump_p (insn) | |
5336 | || tablejump_p (insn, NULL, NULL)) | |
5337 | return false; | |
5338 | ||
5339 | set = single_set (insn); | |
5340 | if (!set || side_effects_p (set)) | |
5341 | return false; | |
5342 | ||
5343 | return true; | |
5344 | } | |
5345 | ||
ffe14686 | 5346 | static basic_block |
229d576c | 5347 | rtl_duplicate_bb (basic_block bb, copy_bb_data *id) |
ffe14686 | 5348 | { |
229d576c | 5349 | bb = cfg_layout_duplicate_bb (bb, id); |
ffe14686 AM |
5350 | bb->aux = NULL; |
5351 | return bb; | |
5352 | } | |
5353 | ||
aa4723d7 | 5354 | /* Do book-keeping of basic block BB for the profile consistency checker. |
160576e1 | 5355 | Store the counting in RECORD. */ |
aa4723d7 | 5356 | static void |
160576e1 | 5357 | rtl_account_profile_record (basic_block bb, struct profile_record *record) |
aa4723d7 | 5358 | { |
8879d71c | 5359 | rtx_insn *insn; |
aa4723d7 SB |
5360 | FOR_BB_INSNS (bb, insn) |
5361 | if (INSN_P (insn)) | |
5362 | { | |
160576e1 | 5363 | record->size += insn_cost (insn, false); |
d1471457 JH |
5364 | if (profile_info) |
5365 | { | |
5366 | if (ENTRY_BLOCK_PTR_FOR_FN (cfun)->count.ipa ().initialized_p () | |
5367 | && ENTRY_BLOCK_PTR_FOR_FN (cfun)->count.ipa ().nonzero_p () | |
5368 | && bb->count.ipa ().initialized_p ()) | |
5369 | record->time | |
5370 | += insn_cost (insn, true) * bb->count.ipa ().to_gcov_type (); | |
5371 | } | |
5372 | else if (bb->count.initialized_p () | |
5373 | && ENTRY_BLOCK_PTR_FOR_FN (cfun)->count.initialized_p ()) | |
160576e1 | 5374 | record->time |
d1471457 JH |
5375 | += insn_cost (insn, true) |
5376 | * bb->count.to_sreal_scale | |
5377 | (ENTRY_BLOCK_PTR_FOR_FN (cfun)->count).to_double (); | |
5378 | else | |
5379 | record->time += insn_cost (insn, true); | |
aa4723d7 SB |
5380 | } |
5381 | } | |
5382 | ||
9ee634e3 JH |
5383 | /* Implementation of CFG manipulation for linearized RTL. */ |
5384 | struct cfg_hooks rtl_cfg_hooks = { | |
f470c378 | 5385 | "rtl", |
9ee634e3 | 5386 | rtl_verify_flow_info, |
10e9fecc | 5387 | rtl_dump_bb, |
2c895bd1 | 5388 | rtl_dump_bb_for_graph, |
bc35512f | 5389 | rtl_create_basic_block, |
9ee634e3 JH |
5390 | rtl_redirect_edge_and_branch, |
5391 | rtl_redirect_edge_and_branch_force, | |
14fa2cc0 | 5392 | rtl_can_remove_branch_p, |
9ee634e3 JH |
5393 | rtl_delete_block, |
5394 | rtl_split_block, | |
f470c378 | 5395 | rtl_move_block_after, |
bc35512f JH |
5396 | rtl_can_merge_blocks, /* can_merge_blocks_p */ |
5397 | rtl_merge_blocks, | |
6de9cd9a DN |
5398 | rtl_predict_edge, |
5399 | rtl_predicted_by_p, | |
ffe14686 AM |
5400 | cfg_layout_can_duplicate_bb_p, |
5401 | rtl_duplicate_bb, | |
f470c378 ZD |
5402 | rtl_split_edge, |
5403 | rtl_make_forwarder_block, | |
6de9cd9a | 5404 | rtl_tidy_fallthru_edge, |
cf103ca4 | 5405 | rtl_force_nonfallthru, |
6de9cd9a DN |
5406 | rtl_block_ends_with_call_p, |
5407 | rtl_block_ends_with_condjump_p, | |
d9d4706f KH |
5408 | rtl_flow_call_edges_add, |
5409 | NULL, /* execute_on_growing_pred */ | |
1cb7dfc3 MH |
5410 | NULL, /* execute_on_shrinking_pred */ |
5411 | NULL, /* duplicate loop for trees */ | |
5412 | NULL, /* lv_add_condition_to_bb */ | |
5413 | NULL, /* lv_adjust_loop_header_phi*/ | |
5414 | NULL, /* extract_cond_bb_edges */ | |
df92c640 SB |
5415 | NULL, /* flush_pending_stmts */ |
5416 | rtl_block_empty_p, /* block_empty_p */ | |
5417 | rtl_split_block_before_cond_jump, /* split_block_before_cond_jump */ | |
aa4723d7 | 5418 | rtl_account_profile_record, |
9ee634e3 JH |
5419 | }; |
5420 | ||
5421 | /* Implementation of CFG manipulation for cfg layout RTL, where | |
5422 | basic block connected via fallthru edges does not have to be adjacent. | |
5423 | This representation will hopefully become the default one in future | |
5424 | version of the compiler. */ | |
6de9cd9a | 5425 | |
9ee634e3 | 5426 | struct cfg_hooks cfg_layout_rtl_cfg_hooks = { |
f470c378 | 5427 | "cfglayout mode", |
bc35512f | 5428 | rtl_verify_flow_info_1, |
10e9fecc | 5429 | rtl_dump_bb, |
2c895bd1 | 5430 | rtl_dump_bb_for_graph, |
bc35512f | 5431 | cfg_layout_create_basic_block, |
9ee634e3 JH |
5432 | cfg_layout_redirect_edge_and_branch, |
5433 | cfg_layout_redirect_edge_and_branch_force, | |
14fa2cc0 | 5434 | rtl_can_remove_branch_p, |
9ee634e3 JH |
5435 | cfg_layout_delete_block, |
5436 | cfg_layout_split_block, | |
f470c378 | 5437 | rtl_move_block_after, |
bc35512f JH |
5438 | cfg_layout_can_merge_blocks_p, |
5439 | cfg_layout_merge_blocks, | |
6de9cd9a DN |
5440 | rtl_predict_edge, |
5441 | rtl_predicted_by_p, | |
5442 | cfg_layout_can_duplicate_bb_p, | |
5443 | cfg_layout_duplicate_bb, | |
f470c378 ZD |
5444 | cfg_layout_split_edge, |
5445 | rtl_make_forwarder_block, | |
cf103ca4 EB |
5446 | NULL, /* tidy_fallthru_edge */ |
5447 | rtl_force_nonfallthru, | |
6de9cd9a DN |
5448 | rtl_block_ends_with_call_p, |
5449 | rtl_block_ends_with_condjump_p, | |
d9d4706f KH |
5450 | rtl_flow_call_edges_add, |
5451 | NULL, /* execute_on_growing_pred */ | |
1cb7dfc3 | 5452 | NULL, /* execute_on_shrinking_pred */ |
a7d4310a | 5453 | duplicate_loop_body_to_header_edge, /* duplicate loop for rtl */ |
1cb7dfc3 MH |
5454 | rtl_lv_add_condition_to_bb, /* lv_add_condition_to_bb */ |
5455 | NULL, /* lv_adjust_loop_header_phi*/ | |
5456 | rtl_extract_cond_bb_edges, /* extract_cond_bb_edges */ | |
df92c640 SB |
5457 | NULL, /* flush_pending_stmts */ |
5458 | rtl_block_empty_p, /* block_empty_p */ | |
5459 | rtl_split_block_before_cond_jump, /* split_block_before_cond_jump */ | |
aa4723d7 | 5460 | rtl_account_profile_record, |
9ee634e3 | 5461 | }; |
78bde837 SB |
5462 | |
5463 | #include "gt-cfgrtl.h" | |
0ecf545c MS |
5464 | |
5465 | #if __GNUC__ >= 10 | |
5466 | # pragma GCC diagnostic pop | |
5467 | #endif |