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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. | |
99dee823 | 3 | Copyright (C) 2010-2021 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: | |
08df6c0d AO |
71 | case SCRATCH: |
72 | /* SCRATCH must be shared because they represent distinct values. */ | |
73 | return x; | |
74 | case CLOBBER: | |
bd1cd0d0 | 75 | /* Share clobbers of hard registers, but do not share pseudo reg |
c5c5ba89 JH |
76 | clobbers or clobbers of hard registers that originated as pseudos. |
77 | This is needed to allow safe register renaming. */ | |
78 | if (REG_P (XEXP (x, 0)) && REGNO (XEXP (x, 0)) < FIRST_PSEUDO_REGISTER | |
79 | && ORIGINAL_REGNO (XEXP (x, 0)) == REGNO (XEXP (x, 0))) | |
08df6c0d AO |
80 | return x; |
81 | break; | |
82 | ||
83 | case CONST: | |
84 | if (shared_const_p (x)) | |
85 | return x; | |
86 | break; | |
87 | ||
88 | case MEM: | |
89 | mem_mode = GET_MODE (x); | |
90 | break; | |
91 | ||
92 | case PRE_INC: | |
93 | case PRE_DEC: | |
cf098191 RS |
94 | { |
95 | gcc_assert (mem_mode != VOIDmode && mem_mode != BLKmode); | |
96 | poly_int64 offset = GET_MODE_SIZE (mem_mode); | |
97 | if (code == PRE_DEC) | |
98 | offset = -offset; | |
99 | return gen_rtx_PLUS (GET_MODE (x), | |
100 | cleanup_auto_inc_dec (XEXP (x, 0), mem_mode), | |
101 | gen_int_mode (offset, GET_MODE (x))); | |
102 | } | |
08df6c0d AO |
103 | |
104 | case POST_INC: | |
105 | case POST_DEC: | |
106 | case PRE_MODIFY: | |
107 | case POST_MODIFY: | |
108 | return cleanup_auto_inc_dec (code == PRE_MODIFY | |
109 | ? XEXP (x, 1) : XEXP (x, 0), | |
110 | mem_mode); | |
111 | ||
112 | default: | |
113 | break; | |
114 | } | |
115 | ||
116 | /* Copy the various flags, fields, and other information. We assume | |
117 | that all fields need copying, and then clear the fields that should | |
118 | not be copied. That is the sensible default behavior, and forces | |
119 | us to explicitly document why we are *not* copying a flag. */ | |
120 | x = shallow_copy_rtx (x); | |
121 | ||
08df6c0d AO |
122 | /* We do not copy FRAME_RELATED for INSNs. */ |
123 | if (INSN_P (x)) | |
124 | RTX_FLAG (x, frame_related) = 0; | |
125 | ||
126 | fmt = GET_RTX_FORMAT (code); | |
127 | for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--) | |
128 | if (fmt[i] == 'e') | |
129 | XEXP (x, i) = cleanup_auto_inc_dec (XEXP (x, i), mem_mode); | |
130 | else if (fmt[i] == 'E' || fmt[i] == 'V') | |
131 | { | |
132 | int j; | |
133 | XVEC (x, i) = rtvec_alloc (XVECLEN (x, i)); | |
134 | for (j = 0; j < XVECLEN (x, i); j++) | |
135 | XVECEXP (x, i, j) | |
136 | = cleanup_auto_inc_dec (XVECEXP (src, i, j), mem_mode); | |
137 | } | |
138 | ||
139 | return x; | |
140 | } | |
08df6c0d AO |
141 | |
142 | /* Auxiliary data structure for propagate_for_debug_stmt. */ | |
143 | ||
144 | struct rtx_subst_pair | |
145 | { | |
146 | rtx to; | |
147 | bool adjusted; | |
53cfcb2e | 148 | rtx_insn *insn; |
08df6c0d AO |
149 | }; |
150 | ||
151 | /* DATA points to an rtx_subst_pair. Return the value that should be | |
152 | substituted. */ | |
153 | ||
154 | static rtx | |
155 | propagate_for_debug_subst (rtx from, const_rtx old_rtx, void *data) | |
156 | { | |
157 | struct rtx_subst_pair *pair = (struct rtx_subst_pair *)data; | |
158 | ||
159 | if (!rtx_equal_p (from, old_rtx)) | |
160 | return NULL_RTX; | |
161 | if (!pair->adjusted) | |
162 | { | |
163 | pair->adjusted = true; | |
08df6c0d | 164 | pair->to = cleanup_auto_inc_dec (pair->to, VOIDmode); |
08df6c0d | 165 | pair->to = make_compound_operation (pair->to, SET); |
53cfcb2e JJ |
166 | /* Avoid propagation from growing DEBUG_INSN expressions too much. */ |
167 | int cnt = 0; | |
168 | subrtx_iterator::array_type array; | |
169 | FOR_EACH_SUBRTX (iter, array, pair->to, ALL) | |
170 | if (REG_P (*iter) && ++cnt > 1) | |
171 | { | |
172 | rtx dval = make_debug_expr_from_rtl (old_rtx); | |
aaa49b45 JJ |
173 | rtx to = pair->to; |
174 | if (volatile_insn_p (to)) | |
175 | to = gen_rtx_UNKNOWN_VAR_LOC (); | |
53cfcb2e JJ |
176 | /* Emit a debug bind insn. */ |
177 | rtx bind | |
178 | = gen_rtx_VAR_LOCATION (GET_MODE (old_rtx), | |
aaa49b45 | 179 | DEBUG_EXPR_TREE_DECL (dval), to, |
53cfcb2e JJ |
180 | VAR_INIT_STATUS_INITIALIZED); |
181 | rtx_insn *bind_insn = emit_debug_insn_before (bind, pair->insn); | |
182 | df_insn_rescan (bind_insn); | |
183 | pair->to = dval; | |
184 | break; | |
185 | } | |
08df6c0d AO |
186 | return pair->to; |
187 | } | |
188 | return copy_rtx (pair->to); | |
189 | } | |
190 | ||
191 | /* Replace all the occurrences of DEST with SRC in DEBUG_INSNs between INSN | |
192 | and LAST, not including INSN, but including LAST. Also stop at the end | |
193 | of THIS_BASIC_BLOCK. */ | |
194 | ||
195 | void | |
dc01c3d1 | 196 | propagate_for_debug (rtx_insn *insn, rtx_insn *last, rtx dest, rtx src, |
08df6c0d AO |
197 | basic_block this_basic_block) |
198 | { | |
b2908ba6 DM |
199 | rtx_insn *next, *end = NEXT_INSN (BB_END (this_basic_block)); |
200 | rtx loc; | |
ef4bddc2 | 201 | rtx (*saved_rtl_hook_no_emit) (machine_mode, rtx); |
08df6c0d AO |
202 | |
203 | struct rtx_subst_pair p; | |
204 | p.to = src; | |
205 | p.adjusted = false; | |
53cfcb2e | 206 | p.insn = NEXT_INSN (insn); |
08df6c0d AO |
207 | |
208 | next = NEXT_INSN (insn); | |
209 | last = NEXT_INSN (last); | |
e90c56c6 JJ |
210 | saved_rtl_hook_no_emit = rtl_hooks.gen_lowpart_no_emit; |
211 | rtl_hooks.gen_lowpart_no_emit = gen_lowpart_for_debug; | |
08df6c0d AO |
212 | while (next != last && next != end) |
213 | { | |
214 | insn = next; | |
215 | next = NEXT_INSN (insn); | |
36f52e8f | 216 | if (DEBUG_BIND_INSN_P (insn)) |
08df6c0d AO |
217 | { |
218 | loc = simplify_replace_fn_rtx (INSN_VAR_LOCATION_LOC (insn), | |
219 | dest, propagate_for_debug_subst, &p); | |
220 | if (loc == INSN_VAR_LOCATION_LOC (insn)) | |
221 | continue; | |
aaa49b45 JJ |
222 | if (volatile_insn_p (loc)) |
223 | loc = gen_rtx_UNKNOWN_VAR_LOC (); | |
08df6c0d AO |
224 | INSN_VAR_LOCATION_LOC (insn) = loc; |
225 | df_insn_rescan (insn); | |
226 | } | |
227 | } | |
e90c56c6 | 228 | rtl_hooks.gen_lowpart_no_emit = saved_rtl_hook_no_emit; |
08df6c0d AO |
229 | } |
230 | ||
231 | /* Initialize DEBUG to an empty list, and clear USED, if given. */ | |
e9f950ba AO |
232 | |
233 | void | |
234 | dead_debug_global_init (struct dead_debug_global *debug, bitmap used) | |
235 | { | |
236 | debug->used = used; | |
c203e8a7 | 237 | debug->htab = NULL; |
e9f950ba AO |
238 | if (used) |
239 | bitmap_clear (used); | |
240 | } | |
241 | ||
242 | /* Initialize DEBUG to an empty list, and clear USED, if given. Link | |
243 | back to GLOBAL, if given, and bring in used bits from it. */ | |
244 | ||
08df6c0d | 245 | void |
e9f950ba AO |
246 | dead_debug_local_init (struct dead_debug_local *debug, bitmap used, |
247 | struct dead_debug_global *global) | |
08df6c0d | 248 | { |
e9f950ba AO |
249 | if (!used && global && global->used) |
250 | used = BITMAP_ALLOC (NULL); | |
251 | ||
08df6c0d | 252 | debug->head = NULL; |
e9f950ba | 253 | debug->global = global; |
08df6c0d AO |
254 | debug->used = used; |
255 | debug->to_rescan = NULL; | |
e9f950ba | 256 | |
08df6c0d | 257 | if (used) |
e9f950ba AO |
258 | { |
259 | if (global && global->used) | |
260 | bitmap_copy (used, global->used); | |
261 | else | |
262 | bitmap_clear (used); | |
263 | } | |
264 | } | |
265 | ||
266 | /* Locate the entry for REG in GLOBAL->htab. */ | |
267 | ||
268 | static dead_debug_global_entry * | |
269 | dead_debug_global_find (struct dead_debug_global *global, rtx reg) | |
270 | { | |
271 | dead_debug_global_entry temp_entry; | |
272 | temp_entry.reg = reg; | |
273 | ||
c203e8a7 | 274 | dead_debug_global_entry *entry = global->htab->find (&temp_entry); |
e9f950ba | 275 | gcc_checking_assert (entry && entry->reg == temp_entry.reg); |
e9f950ba AO |
276 | |
277 | return entry; | |
278 | } | |
279 | ||
280 | /* Insert an entry mapping REG to DTEMP in GLOBAL->htab. */ | |
281 | ||
0e45ec20 | 282 | static dead_debug_global_entry * |
e9f950ba AO |
283 | dead_debug_global_insert (struct dead_debug_global *global, rtx reg, rtx dtemp) |
284 | { | |
285 | dead_debug_global_entry temp_entry; | |
286 | temp_entry.reg = reg; | |
287 | temp_entry.dtemp = dtemp; | |
288 | ||
c203e8a7 TS |
289 | if (!global->htab) |
290 | global->htab = new hash_table<dead_debug_hash_descr> (31); | |
e9f950ba | 291 | |
c203e8a7 TS |
292 | dead_debug_global_entry **slot = global->htab->find_slot (&temp_entry, |
293 | INSERT); | |
e9f950ba AO |
294 | gcc_checking_assert (!*slot); |
295 | *slot = XNEW (dead_debug_global_entry); | |
296 | **slot = temp_entry; | |
0e45ec20 | 297 | return *slot; |
e9f950ba AO |
298 | } |
299 | ||
300 | /* If UREGNO, referenced by USE, is a pseudo marked as used in GLOBAL, | |
026c3cfd | 301 | replace it with a USE of the debug temp recorded for it, and |
e9f950ba AO |
302 | return TRUE. Otherwise, just return FALSE. |
303 | ||
304 | If PTO_RESCAN is given, instead of rescanning modified INSNs right | |
305 | away, add their UIDs to the bitmap, allocating one of *PTO_RESCAN | |
306 | is NULL. */ | |
307 | ||
308 | static bool | |
309 | dead_debug_global_replace_temp (struct dead_debug_global *global, | |
310 | df_ref use, unsigned int uregno, | |
311 | bitmap *pto_rescan) | |
312 | { | |
313 | if (!global || uregno < FIRST_PSEUDO_REGISTER | |
314 | || !global->used | |
0e45ec20 AO |
315 | || !REG_P (*DF_REF_REAL_LOC (use)) |
316 | || REGNO (*DF_REF_REAL_LOC (use)) != uregno | |
e9f950ba AO |
317 | || !bitmap_bit_p (global->used, uregno)) |
318 | return false; | |
319 | ||
e9f950ba AO |
320 | dead_debug_global_entry *entry |
321 | = dead_debug_global_find (global, *DF_REF_REAL_LOC (use)); | |
322 | gcc_checking_assert (GET_CODE (entry->reg) == REG | |
323 | && REGNO (entry->reg) == uregno); | |
324 | ||
0e45ec20 AO |
325 | if (!entry->dtemp) |
326 | return true; | |
327 | ||
e9f950ba AO |
328 | *DF_REF_REAL_LOC (use) = entry->dtemp; |
329 | if (!pto_rescan) | |
330 | df_insn_rescan (DF_REF_INSN (use)); | |
331 | else | |
332 | { | |
333 | if (!*pto_rescan) | |
334 | *pto_rescan = BITMAP_ALLOC (NULL); | |
335 | bitmap_set_bit (*pto_rescan, INSN_UID (DF_REF_INSN (use))); | |
336 | } | |
337 | ||
338 | return true; | |
08df6c0d AO |
339 | } |
340 | ||
341 | /* Reset all debug uses in HEAD, and clear DEBUG->to_rescan bits of | |
342 | each reset insn. DEBUG is not otherwise modified. If HEAD is | |
343 | DEBUG->head, DEBUG->head will be set to NULL at the end. | |
344 | Otherwise, entries from DEBUG->head that pertain to reset insns | |
345 | will be removed, and only then rescanned. */ | |
346 | ||
347 | static void | |
e9f950ba AO |
348 | dead_debug_reset_uses (struct dead_debug_local *debug, |
349 | struct dead_debug_use *head) | |
08df6c0d AO |
350 | { |
351 | bool got_head = (debug->head == head); | |
352 | bitmap rescan; | |
353 | struct dead_debug_use **tailp = &debug->head; | |
354 | struct dead_debug_use *cur; | |
355 | bitmap_iterator bi; | |
356 | unsigned int uid; | |
357 | ||
358 | if (got_head) | |
359 | rescan = NULL; | |
360 | else | |
361 | rescan = BITMAP_ALLOC (NULL); | |
362 | ||
363 | while (head) | |
364 | { | |
365 | struct dead_debug_use *next = head->next; | |
1cbcd833 | 366 | rtx_insn *insn; |
08df6c0d AO |
367 | |
368 | insn = DF_REF_INSN (head->use); | |
369 | if (!next || DF_REF_INSN (next->use) != insn) | |
370 | { | |
371 | INSN_VAR_LOCATION_LOC (insn) = gen_rtx_UNKNOWN_VAR_LOC (); | |
372 | if (got_head) | |
373 | df_insn_rescan_debug_internal (insn); | |
374 | else | |
375 | bitmap_set_bit (rescan, INSN_UID (insn)); | |
376 | if (debug->to_rescan) | |
377 | bitmap_clear_bit (debug->to_rescan, INSN_UID (insn)); | |
378 | } | |
379 | XDELETE (head); | |
380 | head = next; | |
381 | } | |
382 | ||
383 | if (got_head) | |
384 | { | |
385 | debug->head = NULL; | |
386 | return; | |
387 | } | |
388 | ||
389 | while ((cur = *tailp)) | |
390 | if (bitmap_bit_p (rescan, INSN_UID (DF_REF_INSN (cur->use)))) | |
391 | { | |
392 | *tailp = cur->next; | |
393 | XDELETE (cur); | |
394 | } | |
395 | else | |
396 | tailp = &cur->next; | |
397 | ||
398 | EXECUTE_IF_SET_IN_BITMAP (rescan, 0, uid, bi) | |
399 | { | |
400 | struct df_insn_info *insn_info = DF_INSN_UID_SAFE_GET (uid); | |
401 | if (insn_info) | |
402 | df_insn_rescan_debug_internal (insn_info->insn); | |
403 | } | |
404 | ||
405 | BITMAP_FREE (rescan); | |
406 | } | |
407 | ||
e9f950ba AO |
408 | /* Promote pending local uses of pseudos in DEBUG to global |
409 | substitutions. Uses of non-pseudos are left alone for | |
410 | resetting. */ | |
411 | ||
412 | static void | |
413 | dead_debug_promote_uses (struct dead_debug_local *debug) | |
414 | { | |
415 | for (struct dead_debug_use *head = debug->head, **headp = &debug->head; | |
416 | head; head = *headp) | |
417 | { | |
418 | rtx reg = *DF_REF_REAL_LOC (head->use); | |
0e45ec20 AO |
419 | df_ref ref; |
420 | dead_debug_global_entry *entry; | |
e9f950ba AO |
421 | |
422 | if (GET_CODE (reg) != REG | |
423 | || REGNO (reg) < FIRST_PSEUDO_REGISTER) | |
424 | { | |
425 | headp = &head->next; | |
426 | continue; | |
427 | } | |
428 | ||
429 | if (!debug->global->used) | |
430 | debug->global->used = BITMAP_ALLOC (NULL); | |
431 | ||
f39b1a1a AO |
432 | bool added = bitmap_set_bit (debug->global->used, REGNO (reg)); |
433 | gcc_checking_assert (added); | |
434 | ||
435 | entry = dead_debug_global_insert (debug->global, reg, | |
436 | make_debug_expr_from_rtl (reg)); | |
e9f950ba | 437 | |
0e45ec20 AO |
438 | gcc_checking_assert (entry->dtemp); |
439 | ||
440 | /* Tentatively remove the USE from the list. */ | |
e9f950ba | 441 | *headp = head->next; |
0e45ec20 AO |
442 | |
443 | if (!debug->to_rescan) | |
444 | debug->to_rescan = BITMAP_ALLOC (NULL); | |
445 | ||
446 | for (ref = DF_REG_USE_CHAIN (REGNO (reg)); ref; | |
447 | ref = DF_REF_NEXT_REG (ref)) | |
448 | if (DEBUG_INSN_P (DF_REF_INSN (ref))) | |
449 | { | |
450 | if (!dead_debug_global_replace_temp (debug->global, ref, | |
451 | REGNO (reg), | |
452 | &debug->to_rescan)) | |
453 | { | |
1cbcd833 | 454 | rtx_insn *insn = DF_REF_INSN (ref); |
0e45ec20 AO |
455 | INSN_VAR_LOCATION_LOC (insn) = gen_rtx_UNKNOWN_VAR_LOC (); |
456 | bitmap_set_bit (debug->to_rescan, INSN_UID (insn)); | |
457 | } | |
458 | } | |
459 | ||
460 | for (ref = DF_REG_DEF_CHAIN (REGNO (reg)); ref; | |
461 | ref = DF_REF_NEXT_REG (ref)) | |
462 | if (!dead_debug_insert_temp (debug, REGNO (reg), DF_REF_INSN (ref), | |
463 | DEBUG_TEMP_BEFORE_WITH_VALUE)) | |
464 | { | |
465 | rtx bind; | |
466 | bind = gen_rtx_VAR_LOCATION (GET_MODE (reg), | |
467 | DEBUG_EXPR_TREE_DECL (entry->dtemp), | |
468 | gen_rtx_UNKNOWN_VAR_LOC (), | |
469 | VAR_INIT_STATUS_INITIALIZED); | |
1cbcd833 | 470 | rtx_insn *insn = emit_debug_insn_before (bind, DF_REF_INSN (ref)); |
0e45ec20 AO |
471 | bitmap_set_bit (debug->to_rescan, INSN_UID (insn)); |
472 | } | |
473 | ||
474 | entry->dtemp = NULL; | |
e9f950ba AO |
475 | XDELETE (head); |
476 | } | |
477 | } | |
478 | ||
08df6c0d AO |
479 | /* Reset all debug insns with pending uses. Release the bitmap in it, |
480 | unless it is USED. USED must be the same bitmap passed to | |
e9f950ba AO |
481 | dead_debug_local_init. */ |
482 | ||
08df6c0d | 483 | void |
e9f950ba | 484 | dead_debug_local_finish (struct dead_debug_local *debug, bitmap used) |
08df6c0d | 485 | { |
e9f950ba AO |
486 | if (debug->global) |
487 | dead_debug_promote_uses (debug); | |
488 | ||
0e45ec20 AO |
489 | if (debug->used != used) |
490 | BITMAP_FREE (debug->used); | |
491 | ||
08df6c0d AO |
492 | dead_debug_reset_uses (debug, debug->head); |
493 | ||
494 | if (debug->to_rescan) | |
495 | { | |
496 | bitmap_iterator bi; | |
497 | unsigned int uid; | |
498 | ||
499 | EXECUTE_IF_SET_IN_BITMAP (debug->to_rescan, 0, uid, bi) | |
500 | { | |
501 | struct df_insn_info *insn_info = DF_INSN_UID_SAFE_GET (uid); | |
502 | if (insn_info) | |
503 | df_insn_rescan (insn_info->insn); | |
504 | } | |
505 | BITMAP_FREE (debug->to_rescan); | |
506 | } | |
507 | } | |
508 | ||
e9f950ba AO |
509 | /* Release GLOBAL->used unless it is the same as USED. Release the |
510 | mapping hash table if it was initialized. */ | |
511 | ||
512 | void | |
513 | dead_debug_global_finish (struct dead_debug_global *global, bitmap used) | |
514 | { | |
515 | if (global->used != used) | |
516 | BITMAP_FREE (global->used); | |
517 | ||
c203e8a7 TS |
518 | delete global->htab; |
519 | global->htab = NULL; | |
e9f950ba AO |
520 | } |
521 | ||
522 | /* Add USE to DEBUG, or substitute it right away if it's a pseudo in | |
523 | the global substitution list. USE must be a dead reference to | |
524 | UREGNO in a debug insn. Create a bitmap for DEBUG as needed. */ | |
525 | ||
08df6c0d | 526 | void |
e9f950ba | 527 | dead_debug_add (struct dead_debug_local *debug, df_ref use, unsigned int uregno) |
08df6c0d | 528 | { |
e9f950ba AO |
529 | if (dead_debug_global_replace_temp (debug->global, use, uregno, |
530 | &debug->to_rescan)) | |
531 | return; | |
532 | ||
08df6c0d AO |
533 | struct dead_debug_use *newddu = XNEW (struct dead_debug_use); |
534 | ||
535 | newddu->use = use; | |
536 | newddu->next = debug->head; | |
537 | debug->head = newddu; | |
538 | ||
539 | if (!debug->used) | |
540 | debug->used = BITMAP_ALLOC (NULL); | |
541 | ||
542 | /* ??? If we dealt with split multi-registers below, we should set | |
543 | all registers for the used mode in case of hardware | |
544 | registers. */ | |
545 | bitmap_set_bit (debug->used, uregno); | |
546 | } | |
547 | ||
e488c24e JJ |
548 | /* Like lowpart_subreg, but if a subreg is not valid for machine, force |
549 | it anyway - for use in debug insns. */ | |
550 | ||
551 | static rtx | |
552 | debug_lowpart_subreg (machine_mode outer_mode, rtx expr, | |
553 | machine_mode inner_mode) | |
554 | { | |
555 | if (inner_mode == VOIDmode) | |
556 | inner_mode = GET_MODE (expr); | |
91914e56 | 557 | poly_int64 offset = subreg_lowpart_offset (outer_mode, inner_mode); |
e488c24e JJ |
558 | rtx ret = simplify_gen_subreg (outer_mode, expr, inner_mode, offset); |
559 | if (ret) | |
560 | return ret; | |
561 | return gen_rtx_raw_SUBREG (outer_mode, expr, offset); | |
562 | } | |
563 | ||
08df6c0d | 564 | /* If UREGNO is referenced by any entry in DEBUG, emit a debug insn |
e9f950ba AO |
565 | before or after INSN (depending on WHERE), that binds a (possibly |
566 | global) debug temp to the widest-mode use of UREGNO, if WHERE is | |
567 | *_WITH_REG, or the value stored in UREGNO by INSN otherwise, and | |
568 | replace all uses of UREGNO in DEBUG with uses of the debug temp. | |
569 | INSN must be where UREGNO dies, if WHERE is *_BEFORE_*, or where it | |
570 | is set otherwise. Return the number of debug insns emitted. */ | |
571 | ||
08df6c0d | 572 | int |
e9f950ba | 573 | dead_debug_insert_temp (struct dead_debug_local *debug, unsigned int uregno, |
f38a26e5 | 574 | rtx_insn *insn, enum debug_temp_where where) |
08df6c0d AO |
575 | { |
576 | struct dead_debug_use **tailp = &debug->head; | |
577 | struct dead_debug_use *cur; | |
578 | struct dead_debug_use *uses = NULL; | |
579 | struct dead_debug_use **usesp = &uses; | |
e9f950ba | 580 | rtx reg = NULL_RTX; |
08df6c0d | 581 | rtx breg; |
e9f950ba | 582 | rtx dval = NULL_RTX; |
08df6c0d | 583 | rtx bind; |
e9f950ba | 584 | bool global; |
08df6c0d | 585 | |
e9f950ba AO |
586 | if (!debug->used) |
587 | return 0; | |
588 | ||
589 | global = (debug->global && debug->global->used | |
590 | && bitmap_bit_p (debug->global->used, uregno)); | |
591 | ||
592 | if (!global && !bitmap_clear_bit (debug->used, uregno)) | |
08df6c0d AO |
593 | return 0; |
594 | ||
595 | /* Move all uses of uregno from debug->head to uses, setting mode to | |
596 | the widest referenced mode. */ | |
597 | while ((cur = *tailp)) | |
598 | { | |
599 | if (DF_REF_REGNO (cur->use) == uregno) | |
600 | { | |
d540153b JJ |
601 | /* If this loc has been changed e.g. to debug_expr already |
602 | as part of a multi-register use, just drop it. */ | |
603 | if (!REG_P (*DF_REF_REAL_LOC (cur->use))) | |
604 | { | |
605 | *tailp = cur->next; | |
606 | XDELETE (cur); | |
607 | continue; | |
608 | } | |
08df6c0d AO |
609 | *usesp = cur; |
610 | usesp = &cur->next; | |
611 | *tailp = cur->next; | |
612 | cur->next = NULL; | |
73a699ae RS |
613 | /* "may" rather than "must" because we want (for example) |
614 | N V4SFs to win over plain V4SF even though N might be 1. */ | |
615 | rtx candidate = *DF_REF_REAL_LOC (cur->use); | |
08df6c0d | 616 | if (!reg |
73a699ae RS |
617 | || maybe_lt (GET_MODE_BITSIZE (GET_MODE (reg)), |
618 | GET_MODE_BITSIZE (GET_MODE (candidate)))) | |
619 | reg = candidate; | |
08df6c0d AO |
620 | } |
621 | else | |
622 | tailp = &(*tailp)->next; | |
623 | } | |
624 | ||
625 | /* We may have dangling bits in debug->used for registers that were part | |
626 | of a multi-register use, one component of which has been reset. */ | |
627 | if (reg == NULL) | |
628 | { | |
629 | gcc_checking_assert (!uses); | |
e9f950ba AO |
630 | if (!global) |
631 | return 0; | |
632 | } | |
633 | ||
634 | if (global) | |
635 | { | |
636 | if (!reg) | |
637 | reg = regno_reg_rtx[uregno]; | |
638 | dead_debug_global_entry *entry | |
639 | = dead_debug_global_find (debug->global, reg); | |
640 | gcc_checking_assert (entry->reg == reg); | |
641 | dval = entry->dtemp; | |
0e45ec20 AO |
642 | if (!dval) |
643 | return 0; | |
08df6c0d AO |
644 | } |
645 | ||
e9f950ba | 646 | gcc_checking_assert (uses || global); |
08df6c0d AO |
647 | |
648 | breg = reg; | |
649 | /* Recover the expression INSN stores in REG. */ | |
650 | if (where == DEBUG_TEMP_BEFORE_WITH_VALUE) | |
651 | { | |
652 | rtx set = single_set (insn); | |
653 | rtx dest, src; | |
654 | ||
655 | if (set) | |
656 | { | |
657 | dest = SET_DEST (set); | |
658 | src = SET_SRC (set); | |
2689fcc8 AO |
659 | /* Reset uses if the REG-setting insn is a CALL. Asm in |
660 | DEBUG_INSN is never useful, we can't emit debug info for | |
661 | that. And for volatile_insn_p, it is actually harmful - | |
662 | DEBUG_INSNs shouldn't have any side-effects. */ | |
663 | if (GET_CODE (src) == CALL || GET_CODE (src) == ASM_OPERANDS | |
664 | || volatile_insn_p (src)) | |
aaa49b45 | 665 | set = NULL_RTX; |
08df6c0d AO |
666 | } |
667 | ||
668 | /* ??? Should we try to extract it from a PARALLEL? */ | |
669 | if (!set) | |
670 | breg = NULL; | |
671 | /* Cool, it's the same REG, we can use SRC. */ | |
672 | else if (dest == reg) | |
e7206ab1 | 673 | breg = cleanup_auto_inc_dec (src, VOIDmode); |
08df6c0d AO |
674 | else if (REG_P (dest)) |
675 | { | |
676 | /* Hmm... Something's fishy, we should be setting REG here. */ | |
677 | if (REGNO (dest) != REGNO (reg)) | |
678 | breg = NULL; | |
679 | /* If we're not overwriting all the hardware registers that | |
680 | setting REG in its mode would, we won't know what to bind | |
681 | the debug temp to. ??? We could bind the debug_expr to a | |
682 | CONCAT or PARALLEL with the split multi-registers, and | |
683 | replace them as we found the corresponding sets. */ | |
dc8afb70 | 684 | else if (REG_NREGS (reg) != REG_NREGS (dest)) |
08df6c0d AO |
685 | breg = NULL; |
686 | /* Ok, it's the same (hardware) REG, but with a different | |
687 | mode, so SUBREG it. */ | |
688 | else | |
e488c24e JJ |
689 | breg = debug_lowpart_subreg (GET_MODE (reg), |
690 | cleanup_auto_inc_dec (src, VOIDmode), | |
691 | GET_MODE (dest)); | |
08df6c0d AO |
692 | } |
693 | else if (GET_CODE (dest) == SUBREG) | |
694 | { | |
695 | /* We should be setting REG here. Lose. */ | |
696 | if (REGNO (SUBREG_REG (dest)) != REGNO (reg)) | |
697 | breg = NULL; | |
698 | /* Lose if we're setting something other than the lowpart of | |
699 | REG. */ | |
700 | else if (!subreg_lowpart_p (dest)) | |
701 | breg = NULL; | |
702 | /* If we're not overwriting all the hardware registers that | |
703 | setting REG in its mode would, we won't know what to bind | |
704 | the debug temp to. */ | |
705 | else if (REGNO (reg) < FIRST_PSEUDO_REGISTER | |
dc8afb70 | 706 | && (REG_NREGS (reg) |
ad474626 | 707 | != hard_regno_nregs (REGNO (reg), GET_MODE (dest)))) |
08df6c0d AO |
708 | breg = NULL; |
709 | /* Yay, we can use SRC, just adjust its mode. */ | |
710 | else | |
e488c24e JJ |
711 | breg = debug_lowpart_subreg (GET_MODE (reg), |
712 | cleanup_auto_inc_dec (src, VOIDmode), | |
713 | GET_MODE (dest)); | |
08df6c0d AO |
714 | } |
715 | /* Oh well, we're out of luck. */ | |
716 | else | |
717 | breg = NULL; | |
718 | ||
719 | /* We couldn't figure out the value stored in REG, so reset all | |
720 | of its pending debug uses. */ | |
721 | if (!breg) | |
722 | { | |
723 | dead_debug_reset_uses (debug, uses); | |
724 | return 0; | |
725 | } | |
726 | } | |
727 | ||
728 | /* If there's a single (debug) use of an otherwise unused REG, and | |
729 | the debug use is not part of a larger expression, then it | |
730 | probably doesn't make sense to introduce a new debug temp. */ | |
731 | if (where == DEBUG_TEMP_AFTER_WITH_REG && !uses->next) | |
732 | { | |
1cbcd833 | 733 | rtx_insn *next = DF_REF_INSN (uses->use); |
08df6c0d AO |
734 | |
735 | if (DEBUG_INSN_P (next) && reg == INSN_VAR_LOCATION_LOC (next)) | |
736 | { | |
737 | XDELETE (uses); | |
738 | return 0; | |
739 | } | |
740 | } | |
741 | ||
e9f950ba AO |
742 | if (!global) |
743 | /* Create DEBUG_EXPR (and DEBUG_EXPR_DECL). */ | |
744 | dval = make_debug_expr_from_rtl (reg); | |
08df6c0d AO |
745 | |
746 | /* Emit a debug bind insn before the insn in which reg dies. */ | |
747 | bind = gen_rtx_VAR_LOCATION (GET_MODE (reg), | |
748 | DEBUG_EXPR_TREE_DECL (dval), breg, | |
749 | VAR_INIT_STATUS_INITIALIZED); | |
750 | ||
85d87497 JJ |
751 | if (where == DEBUG_TEMP_AFTER_WITH_REG |
752 | || where == DEBUG_TEMP_AFTER_WITH_REG_FORCE) | |
08df6c0d AO |
753 | bind = emit_debug_insn_after (bind, insn); |
754 | else | |
755 | bind = emit_debug_insn_before (bind, insn); | |
36290bb4 AO |
756 | if (debug->to_rescan == NULL) |
757 | debug->to_rescan = BITMAP_ALLOC (NULL); | |
758 | bitmap_set_bit (debug->to_rescan, INSN_UID (bind)); | |
08df6c0d AO |
759 | |
760 | /* Adjust all uses. */ | |
761 | while ((cur = uses)) | |
762 | { | |
763 | if (GET_MODE (*DF_REF_REAL_LOC (cur->use)) == GET_MODE (reg)) | |
764 | *DF_REF_REAL_LOC (cur->use) = dval; | |
765 | else | |
766 | *DF_REF_REAL_LOC (cur->use) | |
e488c24e JJ |
767 | = debug_lowpart_subreg (GET_MODE (*DF_REF_REAL_LOC (cur->use)), dval, |
768 | GET_MODE (dval)); | |
08df6c0d | 769 | /* ??? Should we simplify subreg of subreg? */ |
08df6c0d AO |
770 | bitmap_set_bit (debug->to_rescan, INSN_UID (DF_REF_INSN (cur->use))); |
771 | uses = cur->next; | |
772 | XDELETE (cur); | |
773 | } | |
774 | ||
775 | return 1; | |
776 | } |