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Commit | Line | Data |
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08df6c0d AO |
1 | /* Infrastructure for tracking user variable locations and values |
2 | throughout compilation. | |
a5544970 | 3 | Copyright (C) 2010-2019 Free Software Foundation, Inc. |
08df6c0d AO |
4 | Contributed by Alexandre Oliva <aoliva@redhat.com>. |
5 | ||
6 | This file is part of GCC. | |
7 | ||
8 | GCC is free software; you can redistribute it and/or modify it under | |
9 | the terms of the GNU General Public License as published by the Free | |
10 | Software Foundation; either version 3, or (at your option) any later | |
11 | version. | |
12 | ||
13 | GCC is distributed in the hope that it will be useful, but WITHOUT ANY | |
14 | WARRANTY; without even the implied warranty of MERCHANTABILITY or | |
15 | FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License | |
16 | for more details. | |
17 | ||
18 | You should have received a copy of the GNU General Public License | |
19 | along with GCC; see the file COPYING3. If not see | |
20 | <http://www.gnu.org/licenses/>. */ | |
21 | ||
22 | #include "config.h" | |
23 | #include "system.h" | |
24 | #include "coretypes.h" | |
c7131fb2 | 25 | #include "backend.h" |
08df6c0d | 26 | #include "rtl.h" |
c7131fb2 | 27 | #include "df.h" |
08df6c0d | 28 | #include "valtrack.h" |
08df6c0d | 29 | #include "regs.h" |
4d0cdd0c | 30 | #include "memmodel.h" |
08df6c0d | 31 | #include "emit-rtl.h" |
53cfcb2e | 32 | #include "rtl-iter.h" |
08df6c0d | 33 | |
e90c56c6 JJ |
34 | /* gen_lowpart_no_emit hook implementation for DEBUG_INSNs. In DEBUG_INSNs, |
35 | all lowpart SUBREGs are valid, despite what the machine requires for | |
36 | instructions. */ | |
37 | ||
38 | static rtx | |
ef4bddc2 | 39 | gen_lowpart_for_debug (machine_mode mode, rtx x) |
e90c56c6 JJ |
40 | { |
41 | rtx result = gen_lowpart_if_possible (mode, x); | |
42 | if (result) | |
43 | return result; | |
44 | ||
45 | if (GET_MODE (x) != VOIDmode) | |
46 | return gen_rtx_raw_SUBREG (mode, x, | |
47 | subreg_lowpart_offset (mode, GET_MODE (x))); | |
48 | ||
49 | return NULL_RTX; | |
50 | } | |
51 | ||
08df6c0d AO |
52 | /* Replace auto-increment addressing modes with explicit operations to access |
53 | the same addresses without modifying the corresponding registers. */ | |
54 | ||
08df6c0d | 55 | static rtx |
ef4bddc2 | 56 | cleanup_auto_inc_dec (rtx src, machine_mode mem_mode ATTRIBUTE_UNUSED) |
08df6c0d AO |
57 | { |
58 | rtx x = src; | |
760edf20 | 59 | |
08df6c0d AO |
60 | const RTX_CODE code = GET_CODE (x); |
61 | int i; | |
62 | const char *fmt; | |
63 | ||
64 | switch (code) | |
65 | { | |
66 | case REG: | |
d8116890 | 67 | CASE_CONST_ANY: |
08df6c0d AO |
68 | case SYMBOL_REF: |
69 | case CODE_LABEL: | |
70 | case PC: | |
71 | case CC0: | |
72 | case SCRATCH: | |
73 | /* SCRATCH must be shared because they represent distinct values. */ | |
74 | return x; | |
75 | case CLOBBER: | |
c5c5ba89 JH |
76 | /* Share clobbers of hard registers (like cc0), but do not share pseudo reg |
77 | clobbers or clobbers of hard registers that originated as pseudos. | |
78 | This is needed to allow safe register renaming. */ | |
79 | if (REG_P (XEXP (x, 0)) && REGNO (XEXP (x, 0)) < FIRST_PSEUDO_REGISTER | |
80 | && ORIGINAL_REGNO (XEXP (x, 0)) == REGNO (XEXP (x, 0))) | |
08df6c0d AO |
81 | return x; |
82 | break; | |
83 | ||
84 | case CONST: | |
85 | if (shared_const_p (x)) | |
86 | return x; | |
87 | break; | |
88 | ||
89 | case MEM: | |
90 | mem_mode = GET_MODE (x); | |
91 | break; | |
92 | ||
93 | case PRE_INC: | |
94 | case PRE_DEC: | |
cf098191 RS |
95 | { |
96 | gcc_assert (mem_mode != VOIDmode && mem_mode != BLKmode); | |
97 | poly_int64 offset = GET_MODE_SIZE (mem_mode); | |
98 | if (code == PRE_DEC) | |
99 | offset = -offset; | |
100 | return gen_rtx_PLUS (GET_MODE (x), | |
101 | cleanup_auto_inc_dec (XEXP (x, 0), mem_mode), | |
102 | gen_int_mode (offset, GET_MODE (x))); | |
103 | } | |
08df6c0d AO |
104 | |
105 | case POST_INC: | |
106 | case POST_DEC: | |
107 | case PRE_MODIFY: | |
108 | case POST_MODIFY: | |
109 | return cleanup_auto_inc_dec (code == PRE_MODIFY | |
110 | ? XEXP (x, 1) : XEXP (x, 0), | |
111 | mem_mode); | |
112 | ||
113 | default: | |
114 | break; | |
115 | } | |
116 | ||
117 | /* Copy the various flags, fields, and other information. We assume | |
118 | that all fields need copying, and then clear the fields that should | |
119 | not be copied. That is the sensible default behavior, and forces | |
120 | us to explicitly document why we are *not* copying a flag. */ | |
121 | x = shallow_copy_rtx (x); | |
122 | ||
08df6c0d AO |
123 | /* We do not copy FRAME_RELATED for INSNs. */ |
124 | if (INSN_P (x)) | |
125 | RTX_FLAG (x, frame_related) = 0; | |
126 | ||
127 | fmt = GET_RTX_FORMAT (code); | |
128 | for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--) | |
129 | if (fmt[i] == 'e') | |
130 | XEXP (x, i) = cleanup_auto_inc_dec (XEXP (x, i), mem_mode); | |
131 | else if (fmt[i] == 'E' || fmt[i] == 'V') | |
132 | { | |
133 | int j; | |
134 | XVEC (x, i) = rtvec_alloc (XVECLEN (x, i)); | |
135 | for (j = 0; j < XVECLEN (x, i); j++) | |
136 | XVECEXP (x, i, j) | |
137 | = cleanup_auto_inc_dec (XVECEXP (src, i, j), mem_mode); | |
138 | } | |
139 | ||
140 | return x; | |
141 | } | |
08df6c0d AO |
142 | |
143 | /* Auxiliary data structure for propagate_for_debug_stmt. */ | |
144 | ||
145 | struct rtx_subst_pair | |
146 | { | |
147 | rtx to; | |
148 | bool adjusted; | |
53cfcb2e | 149 | rtx_insn *insn; |
08df6c0d AO |
150 | }; |
151 | ||
152 | /* DATA points to an rtx_subst_pair. Return the value that should be | |
153 | substituted. */ | |
154 | ||
155 | static rtx | |
156 | propagate_for_debug_subst (rtx from, const_rtx old_rtx, void *data) | |
157 | { | |
158 | struct rtx_subst_pair *pair = (struct rtx_subst_pair *)data; | |
159 | ||
160 | if (!rtx_equal_p (from, old_rtx)) | |
161 | return NULL_RTX; | |
162 | if (!pair->adjusted) | |
163 | { | |
164 | pair->adjusted = true; | |
08df6c0d | 165 | pair->to = cleanup_auto_inc_dec (pair->to, VOIDmode); |
08df6c0d | 166 | pair->to = make_compound_operation (pair->to, SET); |
53cfcb2e JJ |
167 | /* Avoid propagation from growing DEBUG_INSN expressions too much. */ |
168 | int cnt = 0; | |
169 | subrtx_iterator::array_type array; | |
170 | FOR_EACH_SUBRTX (iter, array, pair->to, ALL) | |
171 | if (REG_P (*iter) && ++cnt > 1) | |
172 | { | |
173 | rtx dval = make_debug_expr_from_rtl (old_rtx); | |
aaa49b45 JJ |
174 | rtx to = pair->to; |
175 | if (volatile_insn_p (to)) | |
176 | to = gen_rtx_UNKNOWN_VAR_LOC (); | |
53cfcb2e JJ |
177 | /* Emit a debug bind insn. */ |
178 | rtx bind | |
179 | = gen_rtx_VAR_LOCATION (GET_MODE (old_rtx), | |
aaa49b45 | 180 | DEBUG_EXPR_TREE_DECL (dval), to, |
53cfcb2e JJ |
181 | VAR_INIT_STATUS_INITIALIZED); |
182 | rtx_insn *bind_insn = emit_debug_insn_before (bind, pair->insn); | |
183 | df_insn_rescan (bind_insn); | |
184 | pair->to = dval; | |
185 | break; | |
186 | } | |
08df6c0d AO |
187 | return pair->to; |
188 | } | |
189 | return copy_rtx (pair->to); | |
190 | } | |
191 | ||
192 | /* Replace all the occurrences of DEST with SRC in DEBUG_INSNs between INSN | |
193 | and LAST, not including INSN, but including LAST. Also stop at the end | |
194 | of THIS_BASIC_BLOCK. */ | |
195 | ||
196 | void | |
dc01c3d1 | 197 | propagate_for_debug (rtx_insn *insn, rtx_insn *last, rtx dest, rtx src, |
08df6c0d AO |
198 | basic_block this_basic_block) |
199 | { | |
b2908ba6 DM |
200 | rtx_insn *next, *end = NEXT_INSN (BB_END (this_basic_block)); |
201 | rtx loc; | |
ef4bddc2 | 202 | rtx (*saved_rtl_hook_no_emit) (machine_mode, rtx); |
08df6c0d AO |
203 | |
204 | struct rtx_subst_pair p; | |
205 | p.to = src; | |
206 | p.adjusted = false; | |
53cfcb2e | 207 | p.insn = NEXT_INSN (insn); |
08df6c0d AO |
208 | |
209 | next = NEXT_INSN (insn); | |
210 | last = NEXT_INSN (last); | |
e90c56c6 JJ |
211 | saved_rtl_hook_no_emit = rtl_hooks.gen_lowpart_no_emit; |
212 | rtl_hooks.gen_lowpart_no_emit = gen_lowpart_for_debug; | |
08df6c0d AO |
213 | while (next != last && next != end) |
214 | { | |
215 | insn = next; | |
216 | next = NEXT_INSN (insn); | |
36f52e8f | 217 | if (DEBUG_BIND_INSN_P (insn)) |
08df6c0d AO |
218 | { |
219 | loc = simplify_replace_fn_rtx (INSN_VAR_LOCATION_LOC (insn), | |
220 | dest, propagate_for_debug_subst, &p); | |
221 | if (loc == INSN_VAR_LOCATION_LOC (insn)) | |
222 | continue; | |
aaa49b45 JJ |
223 | if (volatile_insn_p (loc)) |
224 | loc = gen_rtx_UNKNOWN_VAR_LOC (); | |
08df6c0d AO |
225 | INSN_VAR_LOCATION_LOC (insn) = loc; |
226 | df_insn_rescan (insn); | |
227 | } | |
228 | } | |
e90c56c6 | 229 | rtl_hooks.gen_lowpart_no_emit = saved_rtl_hook_no_emit; |
08df6c0d AO |
230 | } |
231 | ||
232 | /* Initialize DEBUG to an empty list, and clear USED, if given. */ | |
e9f950ba AO |
233 | |
234 | void | |
235 | dead_debug_global_init (struct dead_debug_global *debug, bitmap used) | |
236 | { | |
237 | debug->used = used; | |
c203e8a7 | 238 | debug->htab = NULL; |
e9f950ba AO |
239 | if (used) |
240 | bitmap_clear (used); | |
241 | } | |
242 | ||
243 | /* Initialize DEBUG to an empty list, and clear USED, if given. Link | |
244 | back to GLOBAL, if given, and bring in used bits from it. */ | |
245 | ||
08df6c0d | 246 | void |
e9f950ba AO |
247 | dead_debug_local_init (struct dead_debug_local *debug, bitmap used, |
248 | struct dead_debug_global *global) | |
08df6c0d | 249 | { |
e9f950ba AO |
250 | if (!used && global && global->used) |
251 | used = BITMAP_ALLOC (NULL); | |
252 | ||
08df6c0d | 253 | debug->head = NULL; |
e9f950ba | 254 | debug->global = global; |
08df6c0d AO |
255 | debug->used = used; |
256 | debug->to_rescan = NULL; | |
e9f950ba | 257 | |
08df6c0d | 258 | if (used) |
e9f950ba AO |
259 | { |
260 | if (global && global->used) | |
261 | bitmap_copy (used, global->used); | |
262 | else | |
263 | bitmap_clear (used); | |
264 | } | |
265 | } | |
266 | ||
267 | /* Locate the entry for REG in GLOBAL->htab. */ | |
268 | ||
269 | static dead_debug_global_entry * | |
270 | dead_debug_global_find (struct dead_debug_global *global, rtx reg) | |
271 | { | |
272 | dead_debug_global_entry temp_entry; | |
273 | temp_entry.reg = reg; | |
274 | ||
c203e8a7 | 275 | dead_debug_global_entry *entry = global->htab->find (&temp_entry); |
e9f950ba | 276 | gcc_checking_assert (entry && entry->reg == temp_entry.reg); |
e9f950ba AO |
277 | |
278 | return entry; | |
279 | } | |
280 | ||
281 | /* Insert an entry mapping REG to DTEMP in GLOBAL->htab. */ | |
282 | ||
0e45ec20 | 283 | static dead_debug_global_entry * |
e9f950ba AO |
284 | dead_debug_global_insert (struct dead_debug_global *global, rtx reg, rtx dtemp) |
285 | { | |
286 | dead_debug_global_entry temp_entry; | |
287 | temp_entry.reg = reg; | |
288 | temp_entry.dtemp = dtemp; | |
289 | ||
c203e8a7 TS |
290 | if (!global->htab) |
291 | global->htab = new hash_table<dead_debug_hash_descr> (31); | |
e9f950ba | 292 | |
c203e8a7 TS |
293 | dead_debug_global_entry **slot = global->htab->find_slot (&temp_entry, |
294 | INSERT); | |
e9f950ba AO |
295 | gcc_checking_assert (!*slot); |
296 | *slot = XNEW (dead_debug_global_entry); | |
297 | **slot = temp_entry; | |
0e45ec20 | 298 | return *slot; |
e9f950ba AO |
299 | } |
300 | ||
301 | /* If UREGNO, referenced by USE, is a pseudo marked as used in GLOBAL, | |
026c3cfd | 302 | replace it with a USE of the debug temp recorded for it, and |
e9f950ba AO |
303 | return TRUE. Otherwise, just return FALSE. |
304 | ||
305 | If PTO_RESCAN is given, instead of rescanning modified INSNs right | |
306 | away, add their UIDs to the bitmap, allocating one of *PTO_RESCAN | |
307 | is NULL. */ | |
308 | ||
309 | static bool | |
310 | dead_debug_global_replace_temp (struct dead_debug_global *global, | |
311 | df_ref use, unsigned int uregno, | |
312 | bitmap *pto_rescan) | |
313 | { | |
314 | if (!global || uregno < FIRST_PSEUDO_REGISTER | |
315 | || !global->used | |
0e45ec20 AO |
316 | || !REG_P (*DF_REF_REAL_LOC (use)) |
317 | || REGNO (*DF_REF_REAL_LOC (use)) != uregno | |
e9f950ba AO |
318 | || !bitmap_bit_p (global->used, uregno)) |
319 | return false; | |
320 | ||
e9f950ba AO |
321 | dead_debug_global_entry *entry |
322 | = dead_debug_global_find (global, *DF_REF_REAL_LOC (use)); | |
323 | gcc_checking_assert (GET_CODE (entry->reg) == REG | |
324 | && REGNO (entry->reg) == uregno); | |
325 | ||
0e45ec20 AO |
326 | if (!entry->dtemp) |
327 | return true; | |
328 | ||
e9f950ba AO |
329 | *DF_REF_REAL_LOC (use) = entry->dtemp; |
330 | if (!pto_rescan) | |
331 | df_insn_rescan (DF_REF_INSN (use)); | |
332 | else | |
333 | { | |
334 | if (!*pto_rescan) | |
335 | *pto_rescan = BITMAP_ALLOC (NULL); | |
336 | bitmap_set_bit (*pto_rescan, INSN_UID (DF_REF_INSN (use))); | |
337 | } | |
338 | ||
339 | return true; | |
08df6c0d AO |
340 | } |
341 | ||
342 | /* Reset all debug uses in HEAD, and clear DEBUG->to_rescan bits of | |
343 | each reset insn. DEBUG is not otherwise modified. If HEAD is | |
344 | DEBUG->head, DEBUG->head will be set to NULL at the end. | |
345 | Otherwise, entries from DEBUG->head that pertain to reset insns | |
346 | will be removed, and only then rescanned. */ | |
347 | ||
348 | static void | |
e9f950ba AO |
349 | dead_debug_reset_uses (struct dead_debug_local *debug, |
350 | struct dead_debug_use *head) | |
08df6c0d AO |
351 | { |
352 | bool got_head = (debug->head == head); | |
353 | bitmap rescan; | |
354 | struct dead_debug_use **tailp = &debug->head; | |
355 | struct dead_debug_use *cur; | |
356 | bitmap_iterator bi; | |
357 | unsigned int uid; | |
358 | ||
359 | if (got_head) | |
360 | rescan = NULL; | |
361 | else | |
362 | rescan = BITMAP_ALLOC (NULL); | |
363 | ||
364 | while (head) | |
365 | { | |
366 | struct dead_debug_use *next = head->next; | |
1cbcd833 | 367 | rtx_insn *insn; |
08df6c0d AO |
368 | |
369 | insn = DF_REF_INSN (head->use); | |
370 | if (!next || DF_REF_INSN (next->use) != insn) | |
371 | { | |
372 | INSN_VAR_LOCATION_LOC (insn) = gen_rtx_UNKNOWN_VAR_LOC (); | |
373 | if (got_head) | |
374 | df_insn_rescan_debug_internal (insn); | |
375 | else | |
376 | bitmap_set_bit (rescan, INSN_UID (insn)); | |
377 | if (debug->to_rescan) | |
378 | bitmap_clear_bit (debug->to_rescan, INSN_UID (insn)); | |
379 | } | |
380 | XDELETE (head); | |
381 | head = next; | |
382 | } | |
383 | ||
384 | if (got_head) | |
385 | { | |
386 | debug->head = NULL; | |
387 | return; | |
388 | } | |
389 | ||
390 | while ((cur = *tailp)) | |
391 | if (bitmap_bit_p (rescan, INSN_UID (DF_REF_INSN (cur->use)))) | |
392 | { | |
393 | *tailp = cur->next; | |
394 | XDELETE (cur); | |
395 | } | |
396 | else | |
397 | tailp = &cur->next; | |
398 | ||
399 | EXECUTE_IF_SET_IN_BITMAP (rescan, 0, uid, bi) | |
400 | { | |
401 | struct df_insn_info *insn_info = DF_INSN_UID_SAFE_GET (uid); | |
402 | if (insn_info) | |
403 | df_insn_rescan_debug_internal (insn_info->insn); | |
404 | } | |
405 | ||
406 | BITMAP_FREE (rescan); | |
407 | } | |
408 | ||
e9f950ba AO |
409 | /* Promote pending local uses of pseudos in DEBUG to global |
410 | substitutions. Uses of non-pseudos are left alone for | |
411 | resetting. */ | |
412 | ||
413 | static void | |
414 | dead_debug_promote_uses (struct dead_debug_local *debug) | |
415 | { | |
416 | for (struct dead_debug_use *head = debug->head, **headp = &debug->head; | |
417 | head; head = *headp) | |
418 | { | |
419 | rtx reg = *DF_REF_REAL_LOC (head->use); | |
0e45ec20 AO |
420 | df_ref ref; |
421 | dead_debug_global_entry *entry; | |
e9f950ba AO |
422 | |
423 | if (GET_CODE (reg) != REG | |
424 | || REGNO (reg) < FIRST_PSEUDO_REGISTER) | |
425 | { | |
426 | headp = &head->next; | |
427 | continue; | |
428 | } | |
429 | ||
430 | if (!debug->global->used) | |
431 | debug->global->used = BITMAP_ALLOC (NULL); | |
432 | ||
f39b1a1a AO |
433 | bool added = bitmap_set_bit (debug->global->used, REGNO (reg)); |
434 | gcc_checking_assert (added); | |
435 | ||
436 | entry = dead_debug_global_insert (debug->global, reg, | |
437 | make_debug_expr_from_rtl (reg)); | |
e9f950ba | 438 | |
0e45ec20 AO |
439 | gcc_checking_assert (entry->dtemp); |
440 | ||
441 | /* Tentatively remove the USE from the list. */ | |
e9f950ba | 442 | *headp = head->next; |
0e45ec20 AO |
443 | |
444 | if (!debug->to_rescan) | |
445 | debug->to_rescan = BITMAP_ALLOC (NULL); | |
446 | ||
447 | for (ref = DF_REG_USE_CHAIN (REGNO (reg)); ref; | |
448 | ref = DF_REF_NEXT_REG (ref)) | |
449 | if (DEBUG_INSN_P (DF_REF_INSN (ref))) | |
450 | { | |
451 | if (!dead_debug_global_replace_temp (debug->global, ref, | |
452 | REGNO (reg), | |
453 | &debug->to_rescan)) | |
454 | { | |
1cbcd833 | 455 | rtx_insn *insn = DF_REF_INSN (ref); |
0e45ec20 AO |
456 | INSN_VAR_LOCATION_LOC (insn) = gen_rtx_UNKNOWN_VAR_LOC (); |
457 | bitmap_set_bit (debug->to_rescan, INSN_UID (insn)); | |
458 | } | |
459 | } | |
460 | ||
461 | for (ref = DF_REG_DEF_CHAIN (REGNO (reg)); ref; | |
462 | ref = DF_REF_NEXT_REG (ref)) | |
463 | if (!dead_debug_insert_temp (debug, REGNO (reg), DF_REF_INSN (ref), | |
464 | DEBUG_TEMP_BEFORE_WITH_VALUE)) | |
465 | { | |
466 | rtx bind; | |
467 | bind = gen_rtx_VAR_LOCATION (GET_MODE (reg), | |
468 | DEBUG_EXPR_TREE_DECL (entry->dtemp), | |
469 | gen_rtx_UNKNOWN_VAR_LOC (), | |
470 | VAR_INIT_STATUS_INITIALIZED); | |
1cbcd833 | 471 | rtx_insn *insn = emit_debug_insn_before (bind, DF_REF_INSN (ref)); |
0e45ec20 AO |
472 | bitmap_set_bit (debug->to_rescan, INSN_UID (insn)); |
473 | } | |
474 | ||
475 | entry->dtemp = NULL; | |
e9f950ba AO |
476 | XDELETE (head); |
477 | } | |
478 | } | |
479 | ||
08df6c0d AO |
480 | /* Reset all debug insns with pending uses. Release the bitmap in it, |
481 | unless it is USED. USED must be the same bitmap passed to | |
e9f950ba AO |
482 | dead_debug_local_init. */ |
483 | ||
08df6c0d | 484 | void |
e9f950ba | 485 | dead_debug_local_finish (struct dead_debug_local *debug, bitmap used) |
08df6c0d | 486 | { |
e9f950ba AO |
487 | if (debug->global) |
488 | dead_debug_promote_uses (debug); | |
489 | ||
0e45ec20 AO |
490 | if (debug->used != used) |
491 | BITMAP_FREE (debug->used); | |
492 | ||
08df6c0d AO |
493 | dead_debug_reset_uses (debug, debug->head); |
494 | ||
495 | if (debug->to_rescan) | |
496 | { | |
497 | bitmap_iterator bi; | |
498 | unsigned int uid; | |
499 | ||
500 | EXECUTE_IF_SET_IN_BITMAP (debug->to_rescan, 0, uid, bi) | |
501 | { | |
502 | struct df_insn_info *insn_info = DF_INSN_UID_SAFE_GET (uid); | |
503 | if (insn_info) | |
504 | df_insn_rescan (insn_info->insn); | |
505 | } | |
506 | BITMAP_FREE (debug->to_rescan); | |
507 | } | |
508 | } | |
509 | ||
e9f950ba AO |
510 | /* Release GLOBAL->used unless it is the same as USED. Release the |
511 | mapping hash table if it was initialized. */ | |
512 | ||
513 | void | |
514 | dead_debug_global_finish (struct dead_debug_global *global, bitmap used) | |
515 | { | |
516 | if (global->used != used) | |
517 | BITMAP_FREE (global->used); | |
518 | ||
c203e8a7 TS |
519 | delete global->htab; |
520 | global->htab = NULL; | |
e9f950ba AO |
521 | } |
522 | ||
523 | /* Add USE to DEBUG, or substitute it right away if it's a pseudo in | |
524 | the global substitution list. USE must be a dead reference to | |
525 | UREGNO in a debug insn. Create a bitmap for DEBUG as needed. */ | |
526 | ||
08df6c0d | 527 | void |
e9f950ba | 528 | dead_debug_add (struct dead_debug_local *debug, df_ref use, unsigned int uregno) |
08df6c0d | 529 | { |
e9f950ba AO |
530 | if (dead_debug_global_replace_temp (debug->global, use, uregno, |
531 | &debug->to_rescan)) | |
532 | return; | |
533 | ||
08df6c0d AO |
534 | struct dead_debug_use *newddu = XNEW (struct dead_debug_use); |
535 | ||
536 | newddu->use = use; | |
537 | newddu->next = debug->head; | |
538 | debug->head = newddu; | |
539 | ||
540 | if (!debug->used) | |
541 | debug->used = BITMAP_ALLOC (NULL); | |
542 | ||
543 | /* ??? If we dealt with split multi-registers below, we should set | |
544 | all registers for the used mode in case of hardware | |
545 | registers. */ | |
546 | bitmap_set_bit (debug->used, uregno); | |
547 | } | |
548 | ||
e488c24e JJ |
549 | /* Like lowpart_subreg, but if a subreg is not valid for machine, force |
550 | it anyway - for use in debug insns. */ | |
551 | ||
552 | static rtx | |
553 | debug_lowpart_subreg (machine_mode outer_mode, rtx expr, | |
554 | machine_mode inner_mode) | |
555 | { | |
556 | if (inner_mode == VOIDmode) | |
557 | inner_mode = GET_MODE (expr); | |
91914e56 | 558 | poly_int64 offset = subreg_lowpart_offset (outer_mode, inner_mode); |
e488c24e JJ |
559 | rtx ret = simplify_gen_subreg (outer_mode, expr, inner_mode, offset); |
560 | if (ret) | |
561 | return ret; | |
562 | return gen_rtx_raw_SUBREG (outer_mode, expr, offset); | |
563 | } | |
564 | ||
08df6c0d | 565 | /* If UREGNO is referenced by any entry in DEBUG, emit a debug insn |
e9f950ba AO |
566 | before or after INSN (depending on WHERE), that binds a (possibly |
567 | global) debug temp to the widest-mode use of UREGNO, if WHERE is | |
568 | *_WITH_REG, or the value stored in UREGNO by INSN otherwise, and | |
569 | replace all uses of UREGNO in DEBUG with uses of the debug temp. | |
570 | INSN must be where UREGNO dies, if WHERE is *_BEFORE_*, or where it | |
571 | is set otherwise. Return the number of debug insns emitted. */ | |
572 | ||
08df6c0d | 573 | int |
e9f950ba | 574 | dead_debug_insert_temp (struct dead_debug_local *debug, unsigned int uregno, |
f38a26e5 | 575 | rtx_insn *insn, enum debug_temp_where where) |
08df6c0d AO |
576 | { |
577 | struct dead_debug_use **tailp = &debug->head; | |
578 | struct dead_debug_use *cur; | |
579 | struct dead_debug_use *uses = NULL; | |
580 | struct dead_debug_use **usesp = &uses; | |
e9f950ba | 581 | rtx reg = NULL_RTX; |
08df6c0d | 582 | rtx breg; |
e9f950ba | 583 | rtx dval = NULL_RTX; |
08df6c0d | 584 | rtx bind; |
e9f950ba | 585 | bool global; |
08df6c0d | 586 | |
e9f950ba AO |
587 | if (!debug->used) |
588 | return 0; | |
589 | ||
590 | global = (debug->global && debug->global->used | |
591 | && bitmap_bit_p (debug->global->used, uregno)); | |
592 | ||
593 | if (!global && !bitmap_clear_bit (debug->used, uregno)) | |
08df6c0d AO |
594 | return 0; |
595 | ||
596 | /* Move all uses of uregno from debug->head to uses, setting mode to | |
597 | the widest referenced mode. */ | |
598 | while ((cur = *tailp)) | |
599 | { | |
600 | if (DF_REF_REGNO (cur->use) == uregno) | |
601 | { | |
d540153b JJ |
602 | /* If this loc has been changed e.g. to debug_expr already |
603 | as part of a multi-register use, just drop it. */ | |
604 | if (!REG_P (*DF_REF_REAL_LOC (cur->use))) | |
605 | { | |
606 | *tailp = cur->next; | |
607 | XDELETE (cur); | |
608 | continue; | |
609 | } | |
08df6c0d AO |
610 | *usesp = cur; |
611 | usesp = &cur->next; | |
612 | *tailp = cur->next; | |
613 | cur->next = NULL; | |
73a699ae RS |
614 | /* "may" rather than "must" because we want (for example) |
615 | N V4SFs to win over plain V4SF even though N might be 1. */ | |
616 | rtx candidate = *DF_REF_REAL_LOC (cur->use); | |
08df6c0d | 617 | if (!reg |
73a699ae RS |
618 | || maybe_lt (GET_MODE_BITSIZE (GET_MODE (reg)), |
619 | GET_MODE_BITSIZE (GET_MODE (candidate)))) | |
620 | reg = candidate; | |
08df6c0d AO |
621 | } |
622 | else | |
623 | tailp = &(*tailp)->next; | |
624 | } | |
625 | ||
626 | /* We may have dangling bits in debug->used for registers that were part | |
627 | of a multi-register use, one component of which has been reset. */ | |
628 | if (reg == NULL) | |
629 | { | |
630 | gcc_checking_assert (!uses); | |
e9f950ba AO |
631 | if (!global) |
632 | return 0; | |
633 | } | |
634 | ||
635 | if (global) | |
636 | { | |
637 | if (!reg) | |
638 | reg = regno_reg_rtx[uregno]; | |
639 | dead_debug_global_entry *entry | |
640 | = dead_debug_global_find (debug->global, reg); | |
641 | gcc_checking_assert (entry->reg == reg); | |
642 | dval = entry->dtemp; | |
0e45ec20 AO |
643 | if (!dval) |
644 | return 0; | |
08df6c0d AO |
645 | } |
646 | ||
e9f950ba | 647 | gcc_checking_assert (uses || global); |
08df6c0d AO |
648 | |
649 | breg = reg; | |
650 | /* Recover the expression INSN stores in REG. */ | |
651 | if (where == DEBUG_TEMP_BEFORE_WITH_VALUE) | |
652 | { | |
653 | rtx set = single_set (insn); | |
654 | rtx dest, src; | |
655 | ||
656 | if (set) | |
657 | { | |
658 | dest = SET_DEST (set); | |
659 | src = SET_SRC (set); | |
2689fcc8 AO |
660 | /* Reset uses if the REG-setting insn is a CALL. Asm in |
661 | DEBUG_INSN is never useful, we can't emit debug info for | |
662 | that. And for volatile_insn_p, it is actually harmful - | |
663 | DEBUG_INSNs shouldn't have any side-effects. */ | |
664 | if (GET_CODE (src) == CALL || GET_CODE (src) == ASM_OPERANDS | |
665 | || volatile_insn_p (src)) | |
aaa49b45 | 666 | set = NULL_RTX; |
08df6c0d AO |
667 | } |
668 | ||
669 | /* ??? Should we try to extract it from a PARALLEL? */ | |
670 | if (!set) | |
671 | breg = NULL; | |
672 | /* Cool, it's the same REG, we can use SRC. */ | |
673 | else if (dest == reg) | |
e7206ab1 | 674 | breg = cleanup_auto_inc_dec (src, VOIDmode); |
08df6c0d AO |
675 | else if (REG_P (dest)) |
676 | { | |
677 | /* Hmm... Something's fishy, we should be setting REG here. */ | |
678 | if (REGNO (dest) != REGNO (reg)) | |
679 | breg = NULL; | |
680 | /* If we're not overwriting all the hardware registers that | |
681 | setting REG in its mode would, we won't know what to bind | |
682 | the debug temp to. ??? We could bind the debug_expr to a | |
683 | CONCAT or PARALLEL with the split multi-registers, and | |
684 | replace them as we found the corresponding sets. */ | |
dc8afb70 | 685 | else if (REG_NREGS (reg) != REG_NREGS (dest)) |
08df6c0d AO |
686 | breg = NULL; |
687 | /* Ok, it's the same (hardware) REG, but with a different | |
688 | mode, so SUBREG it. */ | |
689 | else | |
e488c24e JJ |
690 | breg = debug_lowpart_subreg (GET_MODE (reg), |
691 | cleanup_auto_inc_dec (src, VOIDmode), | |
692 | GET_MODE (dest)); | |
08df6c0d AO |
693 | } |
694 | else if (GET_CODE (dest) == SUBREG) | |
695 | { | |
696 | /* We should be setting REG here. Lose. */ | |
697 | if (REGNO (SUBREG_REG (dest)) != REGNO (reg)) | |
698 | breg = NULL; | |
699 | /* Lose if we're setting something other than the lowpart of | |
700 | REG. */ | |
701 | else if (!subreg_lowpart_p (dest)) | |
702 | breg = NULL; | |
703 | /* If we're not overwriting all the hardware registers that | |
704 | setting REG in its mode would, we won't know what to bind | |
705 | the debug temp to. */ | |
706 | else if (REGNO (reg) < FIRST_PSEUDO_REGISTER | |
dc8afb70 | 707 | && (REG_NREGS (reg) |
ad474626 | 708 | != hard_regno_nregs (REGNO (reg), GET_MODE (dest)))) |
08df6c0d AO |
709 | breg = NULL; |
710 | /* Yay, we can use SRC, just adjust its mode. */ | |
711 | else | |
e488c24e JJ |
712 | breg = debug_lowpart_subreg (GET_MODE (reg), |
713 | cleanup_auto_inc_dec (src, VOIDmode), | |
714 | GET_MODE (dest)); | |
08df6c0d AO |
715 | } |
716 | /* Oh well, we're out of luck. */ | |
717 | else | |
718 | breg = NULL; | |
719 | ||
720 | /* We couldn't figure out the value stored in REG, so reset all | |
721 | of its pending debug uses. */ | |
722 | if (!breg) | |
723 | { | |
724 | dead_debug_reset_uses (debug, uses); | |
725 | return 0; | |
726 | } | |
727 | } | |
728 | ||
729 | /* If there's a single (debug) use of an otherwise unused REG, and | |
730 | the debug use is not part of a larger expression, then it | |
731 | probably doesn't make sense to introduce a new debug temp. */ | |
732 | if (where == DEBUG_TEMP_AFTER_WITH_REG && !uses->next) | |
733 | { | |
1cbcd833 | 734 | rtx_insn *next = DF_REF_INSN (uses->use); |
08df6c0d AO |
735 | |
736 | if (DEBUG_INSN_P (next) && reg == INSN_VAR_LOCATION_LOC (next)) | |
737 | { | |
738 | XDELETE (uses); | |
739 | return 0; | |
740 | } | |
741 | } | |
742 | ||
e9f950ba AO |
743 | if (!global) |
744 | /* Create DEBUG_EXPR (and DEBUG_EXPR_DECL). */ | |
745 | dval = make_debug_expr_from_rtl (reg); | |
08df6c0d AO |
746 | |
747 | /* Emit a debug bind insn before the insn in which reg dies. */ | |
748 | bind = gen_rtx_VAR_LOCATION (GET_MODE (reg), | |
749 | DEBUG_EXPR_TREE_DECL (dval), breg, | |
750 | VAR_INIT_STATUS_INITIALIZED); | |
751 | ||
85d87497 JJ |
752 | if (where == DEBUG_TEMP_AFTER_WITH_REG |
753 | || where == DEBUG_TEMP_AFTER_WITH_REG_FORCE) | |
08df6c0d AO |
754 | bind = emit_debug_insn_after (bind, insn); |
755 | else | |
756 | bind = emit_debug_insn_before (bind, insn); | |
36290bb4 AO |
757 | if (debug->to_rescan == NULL) |
758 | debug->to_rescan = BITMAP_ALLOC (NULL); | |
759 | bitmap_set_bit (debug->to_rescan, INSN_UID (bind)); | |
08df6c0d AO |
760 | |
761 | /* Adjust all uses. */ | |
762 | while ((cur = uses)) | |
763 | { | |
764 | if (GET_MODE (*DF_REF_REAL_LOC (cur->use)) == GET_MODE (reg)) | |
765 | *DF_REF_REAL_LOC (cur->use) = dval; | |
766 | else | |
767 | *DF_REF_REAL_LOC (cur->use) | |
e488c24e JJ |
768 | = debug_lowpart_subreg (GET_MODE (*DF_REF_REAL_LOC (cur->use)), dval, |
769 | GET_MODE (dval)); | |
08df6c0d | 770 | /* ??? Should we simplify subreg of subreg? */ |
08df6c0d AO |
771 | bitmap_set_bit (debug->to_rescan, INSN_UID (DF_REF_INSN (cur->use))); |
772 | uses = cur->next; | |
773 | XDELETE (cur); | |
774 | } | |
775 | ||
776 | return 1; | |
777 | } |