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fa49fd0f RK |
1 | /* Common subexpression elimination library for GNU compiler. |
2 | Copyright (C) 1987, 1988, 1989, 1992, 1993, 1994, 1995, 1996, 1997, 1998, | |
0de3e43f | 3 | 1999, 2000, 2001, 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010 |
8dd5516b | 4 | Free Software Foundation, Inc. |
fa49fd0f | 5 | |
1322177d | 6 | This file is part of GCC. |
fa49fd0f | 7 | |
1322177d LB |
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 | |
9dcd6f09 | 10 | Software Foundation; either version 3, or (at your option) any later |
1322177d | 11 | version. |
fa49fd0f | 12 | |
1322177d LB |
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. | |
fa49fd0f RK |
17 | |
18 | You should have received a copy of the GNU General Public License | |
9dcd6f09 NC |
19 | along with GCC; see the file COPYING3. If not see |
20 | <http://www.gnu.org/licenses/>. */ | |
fa49fd0f RK |
21 | |
22 | #include "config.h" | |
23 | #include "system.h" | |
4977bab6 ZW |
24 | #include "coretypes.h" |
25 | #include "tm.h" | |
fa49fd0f RK |
26 | |
27 | #include "rtl.h" | |
28 | #include "tm_p.h" | |
29 | #include "regs.h" | |
30 | #include "hard-reg-set.h" | |
31 | #include "flags.h" | |
fa49fd0f RK |
32 | #include "insn-config.h" |
33 | #include "recog.h" | |
34 | #include "function.h" | |
78528714 | 35 | #include "emit-rtl.h" |
718f9c0f | 36 | #include "diagnostic-core.h" |
fa49fd0f RK |
37 | #include "toplev.h" |
38 | #include "output.h" | |
39 | #include "ggc.h" | |
fa49fd0f | 40 | #include "hashtab.h" |
b5b8b0ac | 41 | #include "tree-pass.h" |
fa49fd0f | 42 | #include "cselib.h" |
c65ecebc | 43 | #include "params.h" |
6a59927d | 44 | #include "alloc-pool.h" |
29c1846b | 45 | #include "target.h" |
7a8cba34 | 46 | #include "bitmap.h" |
fa49fd0f | 47 | |
463301c3 | 48 | static bool cselib_record_memory; |
457eeaae | 49 | static bool cselib_preserve_constants; |
7080f735 AJ |
50 | static int entry_and_rtx_equal_p (const void *, const void *); |
51 | static hashval_t get_value_hash (const void *); | |
52 | static struct elt_list *new_elt_list (struct elt_list *, cselib_val *); | |
53 | static struct elt_loc_list *new_elt_loc_list (struct elt_loc_list *, rtx); | |
54 | static void unchain_one_value (cselib_val *); | |
55 | static void unchain_one_elt_list (struct elt_list **); | |
56 | static void unchain_one_elt_loc_list (struct elt_loc_list **); | |
7080f735 AJ |
57 | static int discard_useless_locs (void **, void *); |
58 | static int discard_useless_values (void **, void *); | |
59 | static void remove_useless_values (void); | |
29c1846b | 60 | static unsigned int cselib_hash_rtx (rtx, int); |
b5b8b0ac | 61 | static cselib_val *new_cselib_val (unsigned int, enum machine_mode, rtx); |
7080f735 AJ |
62 | static void add_mem_for_addr (cselib_val *, cselib_val *, rtx); |
63 | static cselib_val *cselib_lookup_mem (rtx, int); | |
64 | static void cselib_invalidate_regno (unsigned int, enum machine_mode); | |
7080f735 | 65 | static void cselib_invalidate_mem (rtx); |
7080f735 AJ |
66 | static void cselib_record_set (rtx, cselib_val *, cselib_val *); |
67 | static void cselib_record_sets (rtx); | |
fa49fd0f | 68 | |
b5b8b0ac AO |
69 | struct expand_value_data |
70 | { | |
71 | bitmap regs_active; | |
72 | cselib_expand_callback callback; | |
73 | void *callback_arg; | |
864ddef7 | 74 | bool dummy; |
b5b8b0ac AO |
75 | }; |
76 | ||
77 | static rtx cselib_expand_value_rtx_1 (rtx, struct expand_value_data *, int); | |
78 | ||
fa49fd0f RK |
79 | /* There are three ways in which cselib can look up an rtx: |
80 | - for a REG, the reg_values table (which is indexed by regno) is used | |
81 | - for a MEM, we recursively look up its address and then follow the | |
82 | addr_list of that value | |
83 | - for everything else, we compute a hash value and go through the hash | |
84 | table. Since different rtx's can still have the same hash value, | |
85 | this involves walking the table entries for a given value and comparing | |
86 | the locations of the entries with the rtx we are looking up. */ | |
87 | ||
88 | /* A table that enables us to look up elts by their value. */ | |
7c514720 | 89 | static htab_t cselib_hash_table; |
fa49fd0f RK |
90 | |
91 | /* This is a global so we don't have to pass this through every function. | |
92 | It is used in new_elt_loc_list to set SETTING_INSN. */ | |
93 | static rtx cselib_current_insn; | |
94 | ||
5440c0e7 AO |
95 | /* The unique id that the next create value will take. */ |
96 | static unsigned int next_uid; | |
fa49fd0f RK |
97 | |
98 | /* The number of registers we had when the varrays were last resized. */ | |
99 | static unsigned int cselib_nregs; | |
100 | ||
5847e8da AO |
101 | /* Count values without known locations, or with only locations that |
102 | wouldn't have been known except for debug insns. Whenever this | |
103 | grows too big, we remove these useless values from the table. | |
104 | ||
105 | Counting values with only debug values is a bit tricky. We don't | |
106 | want to increment n_useless_values when we create a value for a | |
107 | debug insn, for this would get n_useless_values out of sync, but we | |
108 | want increment it if all locs in the list that were ever referenced | |
109 | in nondebug insns are removed from the list. | |
110 | ||
111 | In the general case, once we do that, we'd have to stop accepting | |
112 | nondebug expressions in the loc list, to avoid having two values | |
113 | equivalent that, without debug insns, would have been made into | |
114 | separate values. However, because debug insns never introduce | |
115 | equivalences themselves (no assignments), the only means for | |
116 | growing loc lists is through nondebug assignments. If the locs | |
117 | also happen to be referenced in debug insns, it will work just fine. | |
118 | ||
119 | A consequence of this is that there's at most one debug-only loc in | |
120 | each loc list. If we keep it in the first entry, testing whether | |
121 | we have a debug-only loc list takes O(1). | |
122 | ||
123 | Furthermore, since any additional entry in a loc list containing a | |
124 | debug loc would have to come from an assignment (nondebug) that | |
125 | references both the initial debug loc and the newly-equivalent loc, | |
126 | the initial debug loc would be promoted to a nondebug loc, and the | |
127 | loc list would not contain debug locs any more. | |
128 | ||
129 | So the only case we have to be careful with in order to keep | |
130 | n_useless_values in sync between debug and nondebug compilations is | |
131 | to avoid incrementing n_useless_values when removing the single loc | |
132 | from a value that turns out to not appear outside debug values. We | |
133 | increment n_useless_debug_values instead, and leave such values | |
134 | alone until, for other reasons, we garbage-collect useless | |
135 | values. */ | |
fa49fd0f | 136 | static int n_useless_values; |
5847e8da AO |
137 | static int n_useless_debug_values; |
138 | ||
139 | /* Count values whose locs have been taken exclusively from debug | |
140 | insns for the entire life of the value. */ | |
141 | static int n_debug_values; | |
fa49fd0f RK |
142 | |
143 | /* Number of useless values before we remove them from the hash table. */ | |
144 | #define MAX_USELESS_VALUES 32 | |
145 | ||
60fa6660 AO |
146 | /* This table maps from register number to values. It does not |
147 | contain pointers to cselib_val structures, but rather elt_lists. | |
148 | The purpose is to be able to refer to the same register in | |
149 | different modes. The first element of the list defines the mode in | |
150 | which the register was set; if the mode is unknown or the value is | |
151 | no longer valid in that mode, ELT will be NULL for the first | |
152 | element. */ | |
5211d65a KH |
153 | static struct elt_list **reg_values; |
154 | static unsigned int reg_values_size; | |
6790d1ab | 155 | #define REG_VALUES(i) reg_values[i] |
fa49fd0f | 156 | |
31825e57 | 157 | /* The largest number of hard regs used by any entry added to the |
eb232f4e | 158 | REG_VALUES table. Cleared on each cselib_clear_table() invocation. */ |
31825e57 DM |
159 | static unsigned int max_value_regs; |
160 | ||
fa49fd0f | 161 | /* Here the set of indices I with REG_VALUES(I) != 0 is saved. This is used |
eb232f4e | 162 | in cselib_clear_table() for fast emptying. */ |
6790d1ab JH |
163 | static unsigned int *used_regs; |
164 | static unsigned int n_used_regs; | |
fa49fd0f RK |
165 | |
166 | /* We pass this to cselib_invalidate_mem to invalidate all of | |
167 | memory for a non-const call instruction. */ | |
e2500fed | 168 | static GTY(()) rtx callmem; |
fa49fd0f | 169 | |
fa49fd0f RK |
170 | /* Set by discard_useless_locs if it deleted the last location of any |
171 | value. */ | |
172 | static int values_became_useless; | |
7101fb18 JH |
173 | |
174 | /* Used as stop element of the containing_mem list so we can check | |
175 | presence in the list by checking the next pointer. */ | |
176 | static cselib_val dummy_val; | |
177 | ||
457eeaae JJ |
178 | /* If non-NULL, value of the eliminated arg_pointer_rtx or frame_pointer_rtx |
179 | that is constant through the whole function and should never be | |
180 | eliminated. */ | |
181 | static cselib_val *cfa_base_preserved_val; | |
9de9cbaf | 182 | static unsigned int cfa_base_preserved_regno; |
457eeaae | 183 | |
7080f735 | 184 | /* Used to list all values that contain memory reference. |
7101fb18 JH |
185 | May or may not contain the useless values - the list is compacted |
186 | each time memory is invalidated. */ | |
187 | static cselib_val *first_containing_mem = &dummy_val; | |
23bd7a93 | 188 | static alloc_pool elt_loc_list_pool, elt_list_pool, cselib_val_pool, value_pool; |
6fb5fa3c DB |
189 | |
190 | /* If nonnull, cselib will call this function before freeing useless | |
191 | VALUEs. A VALUE is deemed useless if its "locs" field is null. */ | |
192 | void (*cselib_discard_hook) (cselib_val *); | |
b5b8b0ac AO |
193 | |
194 | /* If nonnull, cselib will call this function before recording sets or | |
195 | even clobbering outputs of INSN. All the recorded sets will be | |
196 | represented in the array sets[n_sets]. new_val_min can be used to | |
197 | tell whether values present in sets are introduced by this | |
198 | instruction. */ | |
199 | void (*cselib_record_sets_hook) (rtx insn, struct cselib_set *sets, | |
200 | int n_sets); | |
201 | ||
202 | #define PRESERVED_VALUE_P(RTX) \ | |
203 | (RTL_FLAG_CHECK1("PRESERVED_VALUE_P", (RTX), VALUE)->unchanging) | |
b5b8b0ac | 204 | |
fa49fd0f RK |
205 | \f |
206 | ||
207 | /* Allocate a struct elt_list and fill in its two elements with the | |
208 | arguments. */ | |
209 | ||
6a59927d | 210 | static inline struct elt_list * |
7080f735 | 211 | new_elt_list (struct elt_list *next, cselib_val *elt) |
fa49fd0f | 212 | { |
6a59927d | 213 | struct elt_list *el; |
f883e0a7 | 214 | el = (struct elt_list *) pool_alloc (elt_list_pool); |
fa49fd0f RK |
215 | el->next = next; |
216 | el->elt = elt; | |
217 | return el; | |
218 | } | |
219 | ||
220 | /* Allocate a struct elt_loc_list and fill in its two elements with the | |
221 | arguments. */ | |
222 | ||
6a59927d | 223 | static inline struct elt_loc_list * |
7080f735 | 224 | new_elt_loc_list (struct elt_loc_list *next, rtx loc) |
fa49fd0f | 225 | { |
6a59927d | 226 | struct elt_loc_list *el; |
f883e0a7 | 227 | el = (struct elt_loc_list *) pool_alloc (elt_loc_list_pool); |
fa49fd0f RK |
228 | el->next = next; |
229 | el->loc = loc; | |
230 | el->setting_insn = cselib_current_insn; | |
5847e8da AO |
231 | gcc_assert (!next || !next->setting_insn |
232 | || !DEBUG_INSN_P (next->setting_insn)); | |
233 | ||
234 | /* If we're creating the first loc in a debug insn context, we've | |
235 | just created a debug value. Count it. */ | |
236 | if (!next && cselib_current_insn && DEBUG_INSN_P (cselib_current_insn)) | |
237 | n_debug_values++; | |
238 | ||
fa49fd0f RK |
239 | return el; |
240 | } | |
241 | ||
5847e8da AO |
242 | /* Promote loc L to a nondebug cselib_current_insn if L is marked as |
243 | originating from a debug insn, maintaining the debug values | |
244 | count. */ | |
245 | ||
246 | static inline void | |
247 | promote_debug_loc (struct elt_loc_list *l) | |
248 | { | |
249 | if (l->setting_insn && DEBUG_INSN_P (l->setting_insn) | |
250 | && (!cselib_current_insn || !DEBUG_INSN_P (cselib_current_insn))) | |
251 | { | |
252 | n_debug_values--; | |
253 | l->setting_insn = cselib_current_insn; | |
254 | gcc_assert (!l->next); | |
255 | } | |
256 | } | |
257 | ||
fa49fd0f RK |
258 | /* The elt_list at *PL is no longer needed. Unchain it and free its |
259 | storage. */ | |
260 | ||
6a59927d | 261 | static inline void |
7080f735 | 262 | unchain_one_elt_list (struct elt_list **pl) |
fa49fd0f RK |
263 | { |
264 | struct elt_list *l = *pl; | |
265 | ||
266 | *pl = l->next; | |
6a59927d | 267 | pool_free (elt_list_pool, l); |
fa49fd0f RK |
268 | } |
269 | ||
270 | /* Likewise for elt_loc_lists. */ | |
271 | ||
272 | static void | |
7080f735 | 273 | unchain_one_elt_loc_list (struct elt_loc_list **pl) |
fa49fd0f RK |
274 | { |
275 | struct elt_loc_list *l = *pl; | |
276 | ||
277 | *pl = l->next; | |
6a59927d | 278 | pool_free (elt_loc_list_pool, l); |
fa49fd0f RK |
279 | } |
280 | ||
281 | /* Likewise for cselib_vals. This also frees the addr_list associated with | |
282 | V. */ | |
283 | ||
284 | static void | |
7080f735 | 285 | unchain_one_value (cselib_val *v) |
fa49fd0f RK |
286 | { |
287 | while (v->addr_list) | |
288 | unchain_one_elt_list (&v->addr_list); | |
289 | ||
6a59927d | 290 | pool_free (cselib_val_pool, v); |
fa49fd0f RK |
291 | } |
292 | ||
293 | /* Remove all entries from the hash table. Also used during | |
b5b8b0ac | 294 | initialization. */ |
fa49fd0f | 295 | |
eb232f4e SB |
296 | void |
297 | cselib_clear_table (void) | |
b5b8b0ac | 298 | { |
5440c0e7 | 299 | cselib_reset_table (1); |
b5b8b0ac AO |
300 | } |
301 | ||
457eeaae JJ |
302 | /* Remove from hash table all VALUEs except constants. */ |
303 | ||
304 | static int | |
305 | preserve_only_constants (void **x, void *info ATTRIBUTE_UNUSED) | |
306 | { | |
307 | cselib_val *v = (cselib_val *)*x; | |
308 | ||
309 | if (v->locs != NULL | |
310 | && v->locs->next == NULL) | |
311 | { | |
312 | if (CONSTANT_P (v->locs->loc) | |
313 | && (GET_CODE (v->locs->loc) != CONST | |
314 | || !references_value_p (v->locs->loc, 0))) | |
315 | return 1; | |
316 | if (cfa_base_preserved_val) | |
317 | { | |
318 | if (v == cfa_base_preserved_val) | |
319 | return 1; | |
320 | if (GET_CODE (v->locs->loc) == PLUS | |
321 | && CONST_INT_P (XEXP (v->locs->loc, 1)) | |
322 | && XEXP (v->locs->loc, 0) == cfa_base_preserved_val->val_rtx) | |
323 | return 1; | |
324 | } | |
325 | } | |
326 | ||
327 | htab_clear_slot (cselib_hash_table, x); | |
328 | return 1; | |
329 | } | |
330 | ||
b5b8b0ac AO |
331 | /* Remove all entries from the hash table, arranging for the next |
332 | value to be numbered NUM. */ | |
333 | ||
334 | void | |
5440c0e7 | 335 | cselib_reset_table (unsigned int num) |
fa49fd0f RK |
336 | { |
337 | unsigned int i; | |
338 | ||
31825e57 DM |
339 | max_value_regs = 0; |
340 | ||
457eeaae JJ |
341 | if (cfa_base_preserved_val) |
342 | { | |
9de9cbaf | 343 | unsigned int regno = cfa_base_preserved_regno; |
457eeaae JJ |
344 | unsigned int new_used_regs = 0; |
345 | for (i = 0; i < n_used_regs; i++) | |
346 | if (used_regs[i] == regno) | |
347 | { | |
348 | new_used_regs = 1; | |
349 | continue; | |
350 | } | |
351 | else | |
352 | REG_VALUES (used_regs[i]) = 0; | |
353 | gcc_assert (new_used_regs == 1); | |
354 | n_used_regs = new_used_regs; | |
355 | used_regs[0] = regno; | |
356 | max_value_regs | |
357 | = hard_regno_nregs[regno][GET_MODE (cfa_base_preserved_val->locs->loc)]; | |
358 | } | |
359 | else | |
360 | { | |
361 | for (i = 0; i < n_used_regs; i++) | |
362 | REG_VALUES (used_regs[i]) = 0; | |
363 | n_used_regs = 0; | |
364 | } | |
fa49fd0f | 365 | |
457eeaae JJ |
366 | if (cselib_preserve_constants) |
367 | htab_traverse (cselib_hash_table, preserve_only_constants, NULL); | |
368 | else | |
369 | htab_empty (cselib_hash_table); | |
fa49fd0f | 370 | |
fa49fd0f | 371 | n_useless_values = 0; |
5847e8da AO |
372 | n_useless_debug_values = 0; |
373 | n_debug_values = 0; | |
fa49fd0f | 374 | |
5440c0e7 | 375 | next_uid = num; |
7101fb18 JH |
376 | |
377 | first_containing_mem = &dummy_val; | |
fa49fd0f RK |
378 | } |
379 | ||
b5b8b0ac AO |
380 | /* Return the number of the next value that will be generated. */ |
381 | ||
382 | unsigned int | |
5440c0e7 | 383 | cselib_get_next_uid (void) |
b5b8b0ac | 384 | { |
5440c0e7 | 385 | return next_uid; |
b5b8b0ac AO |
386 | } |
387 | ||
fa49fd0f RK |
388 | /* The equality test for our hash table. The first argument ENTRY is a table |
389 | element (i.e. a cselib_val), while the second arg X is an rtx. We know | |
390 | that all callers of htab_find_slot_with_hash will wrap CONST_INTs into a | |
391 | CONST of an appropriate mode. */ | |
392 | ||
393 | static int | |
7080f735 | 394 | entry_and_rtx_equal_p (const void *entry, const void *x_arg) |
fa49fd0f RK |
395 | { |
396 | struct elt_loc_list *l; | |
e5cfc29f | 397 | const cselib_val *const v = (const cselib_val *) entry; |
f883e0a7 | 398 | rtx x = CONST_CAST_RTX ((const_rtx)x_arg); |
fa49fd0f RK |
399 | enum machine_mode mode = GET_MODE (x); |
400 | ||
481683e1 | 401 | gcc_assert (!CONST_INT_P (x) && GET_CODE (x) != CONST_FIXED |
341c100f | 402 | && (mode != VOIDmode || GET_CODE (x) != CONST_DOUBLE)); |
b8698a0f | 403 | |
757bbef8 | 404 | if (mode != GET_MODE (v->val_rtx)) |
fa49fd0f RK |
405 | return 0; |
406 | ||
407 | /* Unwrap X if necessary. */ | |
408 | if (GET_CODE (x) == CONST | |
481683e1 | 409 | && (CONST_INT_P (XEXP (x, 0)) |
091a3ac7 | 410 | || GET_CODE (XEXP (x, 0)) == CONST_FIXED |
fa49fd0f RK |
411 | || GET_CODE (XEXP (x, 0)) == CONST_DOUBLE)) |
412 | x = XEXP (x, 0); | |
7080f735 | 413 | |
fa49fd0f RK |
414 | /* We don't guarantee that distinct rtx's have different hash values, |
415 | so we need to do a comparison. */ | |
416 | for (l = v->locs; l; l = l->next) | |
417 | if (rtx_equal_for_cselib_p (l->loc, x)) | |
5847e8da AO |
418 | { |
419 | promote_debug_loc (l); | |
420 | return 1; | |
421 | } | |
fa49fd0f RK |
422 | |
423 | return 0; | |
424 | } | |
425 | ||
426 | /* The hash function for our hash table. The value is always computed with | |
0516f6fe SB |
427 | cselib_hash_rtx when adding an element; this function just extracts the |
428 | hash value from a cselib_val structure. */ | |
fa49fd0f | 429 | |
fb7e6024 | 430 | static hashval_t |
7080f735 | 431 | get_value_hash (const void *entry) |
fa49fd0f | 432 | { |
4f588890 | 433 | const cselib_val *const v = (const cselib_val *) entry; |
5440c0e7 | 434 | return v->hash; |
fa49fd0f RK |
435 | } |
436 | ||
437 | /* Return true if X contains a VALUE rtx. If ONLY_USELESS is set, we | |
438 | only return true for values which point to a cselib_val whose value | |
439 | element has been set to zero, which implies the cselib_val will be | |
440 | removed. */ | |
441 | ||
442 | int | |
4f588890 | 443 | references_value_p (const_rtx x, int only_useless) |
fa49fd0f | 444 | { |
4f588890 | 445 | const enum rtx_code code = GET_CODE (x); |
fa49fd0f RK |
446 | const char *fmt = GET_RTX_FORMAT (code); |
447 | int i, j; | |
448 | ||
449 | if (GET_CODE (x) == VALUE | |
450 | && (! only_useless || CSELIB_VAL_PTR (x)->locs == 0)) | |
451 | return 1; | |
452 | ||
453 | for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--) | |
454 | { | |
455 | if (fmt[i] == 'e' && references_value_p (XEXP (x, i), only_useless)) | |
456 | return 1; | |
457 | else if (fmt[i] == 'E') | |
458 | for (j = 0; j < XVECLEN (x, i); j++) | |
459 | if (references_value_p (XVECEXP (x, i, j), only_useless)) | |
460 | return 1; | |
461 | } | |
462 | ||
463 | return 0; | |
464 | } | |
465 | ||
466 | /* For all locations found in X, delete locations that reference useless | |
467 | values (i.e. values without any location). Called through | |
468 | htab_traverse. */ | |
469 | ||
470 | static int | |
7080f735 | 471 | discard_useless_locs (void **x, void *info ATTRIBUTE_UNUSED) |
fa49fd0f RK |
472 | { |
473 | cselib_val *v = (cselib_val *)*x; | |
474 | struct elt_loc_list **p = &v->locs; | |
5847e8da AO |
475 | bool had_locs = v->locs != NULL; |
476 | rtx setting_insn = v->locs ? v->locs->setting_insn : NULL; | |
fa49fd0f RK |
477 | |
478 | while (*p) | |
479 | { | |
480 | if (references_value_p ((*p)->loc, 1)) | |
481 | unchain_one_elt_loc_list (p); | |
482 | else | |
483 | p = &(*p)->next; | |
484 | } | |
485 | ||
b5b8b0ac | 486 | if (had_locs && v->locs == 0 && !PRESERVED_VALUE_P (v->val_rtx)) |
fa49fd0f | 487 | { |
5847e8da AO |
488 | if (setting_insn && DEBUG_INSN_P (setting_insn)) |
489 | n_useless_debug_values++; | |
490 | else | |
491 | n_useless_values++; | |
fa49fd0f RK |
492 | values_became_useless = 1; |
493 | } | |
494 | return 1; | |
495 | } | |
496 | ||
497 | /* If X is a value with no locations, remove it from the hashtable. */ | |
498 | ||
499 | static int | |
7080f735 | 500 | discard_useless_values (void **x, void *info ATTRIBUTE_UNUSED) |
fa49fd0f RK |
501 | { |
502 | cselib_val *v = (cselib_val *)*x; | |
503 | ||
b5b8b0ac | 504 | if (v->locs == 0 && !PRESERVED_VALUE_P (v->val_rtx)) |
fa49fd0f | 505 | { |
6fb5fa3c DB |
506 | if (cselib_discard_hook) |
507 | cselib_discard_hook (v); | |
508 | ||
757bbef8 | 509 | CSELIB_VAL_PTR (v->val_rtx) = NULL; |
7c514720 | 510 | htab_clear_slot (cselib_hash_table, x); |
fa49fd0f RK |
511 | unchain_one_value (v); |
512 | n_useless_values--; | |
513 | } | |
514 | ||
515 | return 1; | |
516 | } | |
517 | ||
518 | /* Clean out useless values (i.e. those which no longer have locations | |
519 | associated with them) from the hash table. */ | |
520 | ||
521 | static void | |
7080f735 | 522 | remove_useless_values (void) |
fa49fd0f | 523 | { |
7101fb18 | 524 | cselib_val **p, *v; |
5847e8da | 525 | |
fa49fd0f RK |
526 | /* First pass: eliminate locations that reference the value. That in |
527 | turn can make more values useless. */ | |
528 | do | |
529 | { | |
530 | values_became_useless = 0; | |
7c514720 | 531 | htab_traverse (cselib_hash_table, discard_useless_locs, 0); |
fa49fd0f RK |
532 | } |
533 | while (values_became_useless); | |
534 | ||
535 | /* Second pass: actually remove the values. */ | |
fa49fd0f | 536 | |
7101fb18 JH |
537 | p = &first_containing_mem; |
538 | for (v = *p; v != &dummy_val; v = v->next_containing_mem) | |
539 | if (v->locs) | |
540 | { | |
541 | *p = v; | |
542 | p = &(*p)->next_containing_mem; | |
543 | } | |
544 | *p = &dummy_val; | |
545 | ||
5847e8da AO |
546 | n_useless_values += n_useless_debug_values; |
547 | n_debug_values -= n_useless_debug_values; | |
548 | n_useless_debug_values = 0; | |
549 | ||
7c514720 | 550 | htab_traverse (cselib_hash_table, discard_useless_values, 0); |
3e2a0bd2 | 551 | |
341c100f | 552 | gcc_assert (!n_useless_values); |
fa49fd0f RK |
553 | } |
554 | ||
b5b8b0ac AO |
555 | /* Arrange for a value to not be removed from the hash table even if |
556 | it becomes useless. */ | |
557 | ||
558 | void | |
559 | cselib_preserve_value (cselib_val *v) | |
560 | { | |
561 | PRESERVED_VALUE_P (v->val_rtx) = 1; | |
562 | } | |
563 | ||
564 | /* Test whether a value is preserved. */ | |
565 | ||
566 | bool | |
567 | cselib_preserved_value_p (cselib_val *v) | |
568 | { | |
569 | return PRESERVED_VALUE_P (v->val_rtx); | |
570 | } | |
571 | ||
457eeaae JJ |
572 | /* Arrange for a REG value to be assumed constant through the whole function, |
573 | never invalidated and preserved across cselib_reset_table calls. */ | |
574 | ||
575 | void | |
9de9cbaf | 576 | cselib_preserve_cfa_base_value (cselib_val *v, unsigned int regno) |
457eeaae JJ |
577 | { |
578 | if (cselib_preserve_constants | |
579 | && v->locs | |
580 | && REG_P (v->locs->loc)) | |
9de9cbaf JJ |
581 | { |
582 | cfa_base_preserved_val = v; | |
583 | cfa_base_preserved_regno = regno; | |
584 | } | |
457eeaae JJ |
585 | } |
586 | ||
b5b8b0ac AO |
587 | /* Clean all non-constant expressions in the hash table, but retain |
588 | their values. */ | |
589 | ||
590 | void | |
0de3e43f | 591 | cselib_preserve_only_values (void) |
b5b8b0ac AO |
592 | { |
593 | int i; | |
594 | ||
b5b8b0ac AO |
595 | for (i = 0; i < FIRST_PSEUDO_REGISTER; i++) |
596 | cselib_invalidate_regno (i, reg_raw_mode[i]); | |
597 | ||
598 | cselib_invalidate_mem (callmem); | |
599 | ||
600 | remove_useless_values (); | |
601 | ||
602 | gcc_assert (first_containing_mem == &dummy_val); | |
603 | } | |
604 | ||
60fa6660 AO |
605 | /* Return the mode in which a register was last set. If X is not a |
606 | register, return its mode. If the mode in which the register was | |
607 | set is not known, or the value was already clobbered, return | |
608 | VOIDmode. */ | |
609 | ||
610 | enum machine_mode | |
4f588890 | 611 | cselib_reg_set_mode (const_rtx x) |
60fa6660 | 612 | { |
f8cfc6aa | 613 | if (!REG_P (x)) |
60fa6660 AO |
614 | return GET_MODE (x); |
615 | ||
616 | if (REG_VALUES (REGNO (x)) == NULL | |
617 | || REG_VALUES (REGNO (x))->elt == NULL) | |
618 | return VOIDmode; | |
619 | ||
757bbef8 | 620 | return GET_MODE (REG_VALUES (REGNO (x))->elt->val_rtx); |
60fa6660 AO |
621 | } |
622 | ||
fa49fd0f RK |
623 | /* Return nonzero if we can prove that X and Y contain the same value, taking |
624 | our gathered information into account. */ | |
625 | ||
626 | int | |
7080f735 | 627 | rtx_equal_for_cselib_p (rtx x, rtx y) |
fa49fd0f RK |
628 | { |
629 | enum rtx_code code; | |
630 | const char *fmt; | |
631 | int i; | |
7080f735 | 632 | |
f8cfc6aa | 633 | if (REG_P (x) || MEM_P (x)) |
fa49fd0f RK |
634 | { |
635 | cselib_val *e = cselib_lookup (x, GET_MODE (x), 0); | |
636 | ||
637 | if (e) | |
757bbef8 | 638 | x = e->val_rtx; |
fa49fd0f RK |
639 | } |
640 | ||
f8cfc6aa | 641 | if (REG_P (y) || MEM_P (y)) |
fa49fd0f RK |
642 | { |
643 | cselib_val *e = cselib_lookup (y, GET_MODE (y), 0); | |
644 | ||
645 | if (e) | |
757bbef8 | 646 | y = e->val_rtx; |
fa49fd0f RK |
647 | } |
648 | ||
649 | if (x == y) | |
650 | return 1; | |
651 | ||
652 | if (GET_CODE (x) == VALUE && GET_CODE (y) == VALUE) | |
653 | return CSELIB_VAL_PTR (x) == CSELIB_VAL_PTR (y); | |
654 | ||
655 | if (GET_CODE (x) == VALUE) | |
656 | { | |
657 | cselib_val *e = CSELIB_VAL_PTR (x); | |
658 | struct elt_loc_list *l; | |
659 | ||
660 | for (l = e->locs; l; l = l->next) | |
661 | { | |
662 | rtx t = l->loc; | |
663 | ||
664 | /* Avoid infinite recursion. */ | |
3c0cb5de | 665 | if (REG_P (t) || MEM_P (t)) |
fa49fd0f RK |
666 | continue; |
667 | else if (rtx_equal_for_cselib_p (t, y)) | |
668 | return 1; | |
669 | } | |
7080f735 | 670 | |
fa49fd0f RK |
671 | return 0; |
672 | } | |
673 | ||
674 | if (GET_CODE (y) == VALUE) | |
675 | { | |
676 | cselib_val *e = CSELIB_VAL_PTR (y); | |
677 | struct elt_loc_list *l; | |
678 | ||
679 | for (l = e->locs; l; l = l->next) | |
680 | { | |
681 | rtx t = l->loc; | |
682 | ||
3c0cb5de | 683 | if (REG_P (t) || MEM_P (t)) |
fa49fd0f RK |
684 | continue; |
685 | else if (rtx_equal_for_cselib_p (x, t)) | |
686 | return 1; | |
687 | } | |
7080f735 | 688 | |
fa49fd0f RK |
689 | return 0; |
690 | } | |
691 | ||
692 | if (GET_CODE (x) != GET_CODE (y) || GET_MODE (x) != GET_MODE (y)) | |
693 | return 0; | |
694 | ||
37cf6116 RH |
695 | /* These won't be handled correctly by the code below. */ |
696 | switch (GET_CODE (x)) | |
697 | { | |
698 | case CONST_DOUBLE: | |
091a3ac7 | 699 | case CONST_FIXED: |
0ca5af51 | 700 | case DEBUG_EXPR: |
37cf6116 RH |
701 | return 0; |
702 | ||
703 | case LABEL_REF: | |
704 | return XEXP (x, 0) == XEXP (y, 0); | |
705 | ||
706 | default: | |
707 | break; | |
708 | } | |
7080f735 | 709 | |
fa49fd0f RK |
710 | code = GET_CODE (x); |
711 | fmt = GET_RTX_FORMAT (code); | |
712 | ||
713 | for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--) | |
714 | { | |
715 | int j; | |
716 | ||
717 | switch (fmt[i]) | |
718 | { | |
719 | case 'w': | |
720 | if (XWINT (x, i) != XWINT (y, i)) | |
721 | return 0; | |
722 | break; | |
723 | ||
724 | case 'n': | |
725 | case 'i': | |
726 | if (XINT (x, i) != XINT (y, i)) | |
727 | return 0; | |
728 | break; | |
729 | ||
730 | case 'V': | |
731 | case 'E': | |
732 | /* Two vectors must have the same length. */ | |
733 | if (XVECLEN (x, i) != XVECLEN (y, i)) | |
734 | return 0; | |
735 | ||
736 | /* And the corresponding elements must match. */ | |
737 | for (j = 0; j < XVECLEN (x, i); j++) | |
738 | if (! rtx_equal_for_cselib_p (XVECEXP (x, i, j), | |
739 | XVECEXP (y, i, j))) | |
740 | return 0; | |
741 | break; | |
742 | ||
743 | case 'e': | |
29c1846b R |
744 | if (i == 1 |
745 | && targetm.commutative_p (x, UNKNOWN) | |
746 | && rtx_equal_for_cselib_p (XEXP (x, 1), XEXP (y, 0)) | |
747 | && rtx_equal_for_cselib_p (XEXP (x, 0), XEXP (y, 1))) | |
748 | return 1; | |
fa49fd0f RK |
749 | if (! rtx_equal_for_cselib_p (XEXP (x, i), XEXP (y, i))) |
750 | return 0; | |
751 | break; | |
752 | ||
753 | case 'S': | |
754 | case 's': | |
755 | if (strcmp (XSTR (x, i), XSTR (y, i))) | |
756 | return 0; | |
757 | break; | |
758 | ||
759 | case 'u': | |
760 | /* These are just backpointers, so they don't matter. */ | |
761 | break; | |
762 | ||
763 | case '0': | |
764 | case 't': | |
765 | break; | |
766 | ||
767 | /* It is believed that rtx's at this level will never | |
768 | contain anything but integers and other rtx's, | |
769 | except for within LABEL_REFs and SYMBOL_REFs. */ | |
770 | default: | |
341c100f | 771 | gcc_unreachable (); |
fa49fd0f RK |
772 | } |
773 | } | |
774 | return 1; | |
775 | } | |
776 | ||
3af4ba41 RS |
777 | /* We need to pass down the mode of constants through the hash table |
778 | functions. For that purpose, wrap them in a CONST of the appropriate | |
779 | mode. */ | |
780 | static rtx | |
781 | wrap_constant (enum machine_mode mode, rtx x) | |
782 | { | |
783 | if (!CONST_INT_P (x) && GET_CODE (x) != CONST_FIXED | |
784 | && (GET_CODE (x) != CONST_DOUBLE || GET_MODE (x) != VOIDmode)) | |
785 | return x; | |
786 | gcc_assert (mode != VOIDmode); | |
787 | return gen_rtx_CONST (mode, x); | |
788 | } | |
789 | ||
fa49fd0f RK |
790 | /* Hash an rtx. Return 0 if we couldn't hash the rtx. |
791 | For registers and memory locations, we look up their cselib_val structure | |
792 | and return its VALUE element. | |
793 | Possible reasons for return 0 are: the object is volatile, or we couldn't | |
794 | find a register or memory location in the table and CREATE is zero. If | |
795 | CREATE is nonzero, table elts are created for regs and mem. | |
29c1846b R |
796 | N.B. this hash function returns the same hash value for RTXes that |
797 | differ only in the order of operands, thus it is suitable for comparisons | |
798 | that take commutativity into account. | |
799 | If we wanted to also support associative rules, we'd have to use a different | |
800 | strategy to avoid returning spurious 0, e.g. return ~(~0U >> 1) . | |
801 | We used to have a MODE argument for hashing for CONST_INTs, but that | |
802 | didn't make sense, since it caused spurious hash differences between | |
803 | (set (reg:SI 1) (const_int)) | |
804 | (plus:SI (reg:SI 2) (reg:SI 1)) | |
805 | and | |
806 | (plus:SI (reg:SI 2) (const_int)) | |
807 | If the mode is important in any context, it must be checked specifically | |
808 | in a comparison anyway, since relying on hash differences is unsafe. */ | |
fa49fd0f RK |
809 | |
810 | static unsigned int | |
29c1846b | 811 | cselib_hash_rtx (rtx x, int create) |
fa49fd0f RK |
812 | { |
813 | cselib_val *e; | |
814 | int i, j; | |
815 | enum rtx_code code; | |
816 | const char *fmt; | |
817 | unsigned int hash = 0; | |
818 | ||
fa49fd0f RK |
819 | code = GET_CODE (x); |
820 | hash += (unsigned) code + (unsigned) GET_MODE (x); | |
821 | ||
822 | switch (code) | |
823 | { | |
824 | case MEM: | |
825 | case REG: | |
826 | e = cselib_lookup (x, GET_MODE (x), create); | |
827 | if (! e) | |
828 | return 0; | |
829 | ||
5440c0e7 | 830 | return e->hash; |
fa49fd0f | 831 | |
0ca5af51 | 832 | case DEBUG_EXPR: |
e4fb38bd JJ |
833 | hash += ((unsigned) DEBUG_EXPR << 7) |
834 | + DEBUG_TEMP_UID (DEBUG_EXPR_TREE_DECL (x)); | |
0ca5af51 AO |
835 | return hash ? hash : (unsigned int) DEBUG_EXPR; |
836 | ||
fa49fd0f | 837 | case CONST_INT: |
29c1846b | 838 | hash += ((unsigned) CONST_INT << 7) + INTVAL (x); |
dc76f41c | 839 | return hash ? hash : (unsigned int) CONST_INT; |
fa49fd0f RK |
840 | |
841 | case CONST_DOUBLE: | |
842 | /* This is like the general case, except that it only counts | |
843 | the integers representing the constant. */ | |
844 | hash += (unsigned) code + (unsigned) GET_MODE (x); | |
845 | if (GET_MODE (x) != VOIDmode) | |
46b33600 | 846 | hash += real_hash (CONST_DOUBLE_REAL_VALUE (x)); |
fa49fd0f RK |
847 | else |
848 | hash += ((unsigned) CONST_DOUBLE_LOW (x) | |
849 | + (unsigned) CONST_DOUBLE_HIGH (x)); | |
dc76f41c | 850 | return hash ? hash : (unsigned int) CONST_DOUBLE; |
fa49fd0f | 851 | |
091a3ac7 CF |
852 | case CONST_FIXED: |
853 | hash += (unsigned int) code + (unsigned int) GET_MODE (x); | |
854 | hash += fixed_hash (CONST_FIXED_VALUE (x)); | |
855 | return hash ? hash : (unsigned int) CONST_FIXED; | |
856 | ||
69ef87e2 AH |
857 | case CONST_VECTOR: |
858 | { | |
859 | int units; | |
860 | rtx elt; | |
861 | ||
862 | units = CONST_VECTOR_NUNITS (x); | |
863 | ||
864 | for (i = 0; i < units; ++i) | |
865 | { | |
866 | elt = CONST_VECTOR_ELT (x, i); | |
29c1846b | 867 | hash += cselib_hash_rtx (elt, 0); |
69ef87e2 AH |
868 | } |
869 | ||
870 | return hash; | |
871 | } | |
872 | ||
fa49fd0f RK |
873 | /* Assume there is only one rtx object for any given label. */ |
874 | case LABEL_REF: | |
4c6669c2 RS |
875 | /* We don't hash on the address of the CODE_LABEL to avoid bootstrap |
876 | differences and differences between each stage's debugging dumps. */ | |
877 | hash += (((unsigned int) LABEL_REF << 7) | |
878 | + CODE_LABEL_NUMBER (XEXP (x, 0))); | |
dc76f41c | 879 | return hash ? hash : (unsigned int) LABEL_REF; |
fa49fd0f RK |
880 | |
881 | case SYMBOL_REF: | |
4c6669c2 RS |
882 | { |
883 | /* Don't hash on the symbol's address to avoid bootstrap differences. | |
884 | Different hash values may cause expressions to be recorded in | |
885 | different orders and thus different registers to be used in the | |
886 | final assembler. This also avoids differences in the dump files | |
887 | between various stages. */ | |
888 | unsigned int h = 0; | |
889 | const unsigned char *p = (const unsigned char *) XSTR (x, 0); | |
890 | ||
891 | while (*p) | |
892 | h += (h << 7) + *p++; /* ??? revisit */ | |
893 | ||
894 | hash += ((unsigned int) SYMBOL_REF << 7) + h; | |
895 | return hash ? hash : (unsigned int) SYMBOL_REF; | |
896 | } | |
fa49fd0f RK |
897 | |
898 | case PRE_DEC: | |
899 | case PRE_INC: | |
900 | case POST_DEC: | |
901 | case POST_INC: | |
902 | case POST_MODIFY: | |
903 | case PRE_MODIFY: | |
904 | case PC: | |
905 | case CC0: | |
906 | case CALL: | |
907 | case UNSPEC_VOLATILE: | |
908 | return 0; | |
909 | ||
910 | case ASM_OPERANDS: | |
911 | if (MEM_VOLATILE_P (x)) | |
912 | return 0; | |
913 | ||
914 | break; | |
7080f735 | 915 | |
fa49fd0f RK |
916 | default: |
917 | break; | |
918 | } | |
919 | ||
920 | i = GET_RTX_LENGTH (code) - 1; | |
921 | fmt = GET_RTX_FORMAT (code); | |
922 | for (; i >= 0; i--) | |
923 | { | |
341c100f | 924 | switch (fmt[i]) |
fa49fd0f | 925 | { |
341c100f | 926 | case 'e': |
fa49fd0f | 927 | { |
341c100f | 928 | rtx tem = XEXP (x, i); |
29c1846b | 929 | unsigned int tem_hash = cselib_hash_rtx (tem, create); |
b8698a0f | 930 | |
fa49fd0f RK |
931 | if (tem_hash == 0) |
932 | return 0; | |
b8698a0f | 933 | |
fa49fd0f RK |
934 | hash += tem_hash; |
935 | } | |
341c100f NS |
936 | break; |
937 | case 'E': | |
938 | for (j = 0; j < XVECLEN (x, i); j++) | |
939 | { | |
940 | unsigned int tem_hash | |
29c1846b | 941 | = cselib_hash_rtx (XVECEXP (x, i, j), create); |
b8698a0f | 942 | |
341c100f NS |
943 | if (tem_hash == 0) |
944 | return 0; | |
b8698a0f | 945 | |
341c100f NS |
946 | hash += tem_hash; |
947 | } | |
948 | break; | |
fa49fd0f | 949 | |
341c100f NS |
950 | case 's': |
951 | { | |
952 | const unsigned char *p = (const unsigned char *) XSTR (x, i); | |
b8698a0f | 953 | |
341c100f NS |
954 | if (p) |
955 | while (*p) | |
956 | hash += *p++; | |
957 | break; | |
958 | } | |
b8698a0f | 959 | |
341c100f NS |
960 | case 'i': |
961 | hash += XINT (x, i); | |
962 | break; | |
963 | ||
964 | case '0': | |
965 | case 't': | |
966 | /* unused */ | |
967 | break; | |
b8698a0f | 968 | |
341c100f NS |
969 | default: |
970 | gcc_unreachable (); | |
fa49fd0f | 971 | } |
fa49fd0f RK |
972 | } |
973 | ||
dc76f41c | 974 | return hash ? hash : 1 + (unsigned int) GET_CODE (x); |
fa49fd0f RK |
975 | } |
976 | ||
977 | /* Create a new value structure for VALUE and initialize it. The mode of the | |
978 | value is MODE. */ | |
979 | ||
6a59927d | 980 | static inline cselib_val * |
5440c0e7 | 981 | new_cselib_val (unsigned int hash, enum machine_mode mode, rtx x) |
fa49fd0f | 982 | { |
f883e0a7 | 983 | cselib_val *e = (cselib_val *) pool_alloc (cselib_val_pool); |
fa49fd0f | 984 | |
5440c0e7 AO |
985 | gcc_assert (hash); |
986 | gcc_assert (next_uid); | |
fa49fd0f | 987 | |
5440c0e7 AO |
988 | e->hash = hash; |
989 | e->uid = next_uid++; | |
d67fb775 SB |
990 | /* We use an alloc pool to allocate this RTL construct because it |
991 | accounts for about 8% of the overall memory usage. We know | |
992 | precisely when we can have VALUE RTXen (when cselib is active) | |
daa956d0 | 993 | so we don't need to put them in garbage collected memory. |
d67fb775 | 994 | ??? Why should a VALUE be an RTX in the first place? */ |
f883e0a7 | 995 | e->val_rtx = (rtx) pool_alloc (value_pool); |
757bbef8 SB |
996 | memset (e->val_rtx, 0, RTX_HDR_SIZE); |
997 | PUT_CODE (e->val_rtx, VALUE); | |
998 | PUT_MODE (e->val_rtx, mode); | |
999 | CSELIB_VAL_PTR (e->val_rtx) = e; | |
fa49fd0f RK |
1000 | e->addr_list = 0; |
1001 | e->locs = 0; | |
7101fb18 | 1002 | e->next_containing_mem = 0; |
b5b8b0ac AO |
1003 | |
1004 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
1005 | { | |
5440c0e7 | 1006 | fprintf (dump_file, "cselib value %u:%u ", e->uid, hash); |
b5b8b0ac AO |
1007 | if (flag_dump_noaddr || flag_dump_unnumbered) |
1008 | fputs ("# ", dump_file); | |
1009 | else | |
1010 | fprintf (dump_file, "%p ", (void*)e); | |
1011 | print_rtl_single (dump_file, x); | |
1012 | fputc ('\n', dump_file); | |
1013 | } | |
1014 | ||
fa49fd0f RK |
1015 | return e; |
1016 | } | |
1017 | ||
1018 | /* ADDR_ELT is a value that is used as address. MEM_ELT is the value that | |
1019 | contains the data at this address. X is a MEM that represents the | |
1020 | value. Update the two value structures to represent this situation. */ | |
1021 | ||
1022 | static void | |
7080f735 | 1023 | add_mem_for_addr (cselib_val *addr_elt, cselib_val *mem_elt, rtx x) |
fa49fd0f | 1024 | { |
fa49fd0f RK |
1025 | struct elt_loc_list *l; |
1026 | ||
1027 | /* Avoid duplicates. */ | |
1028 | for (l = mem_elt->locs; l; l = l->next) | |
3c0cb5de | 1029 | if (MEM_P (l->loc) |
fa49fd0f | 1030 | && CSELIB_VAL_PTR (XEXP (l->loc, 0)) == addr_elt) |
5847e8da AO |
1031 | { |
1032 | promote_debug_loc (l); | |
1033 | return; | |
1034 | } | |
fa49fd0f | 1035 | |
fa49fd0f | 1036 | addr_elt->addr_list = new_elt_list (addr_elt->addr_list, mem_elt); |
f1ec5147 RK |
1037 | mem_elt->locs |
1038 | = new_elt_loc_list (mem_elt->locs, | |
757bbef8 | 1039 | replace_equiv_address_nv (x, addr_elt->val_rtx)); |
7101fb18 JH |
1040 | if (mem_elt->next_containing_mem == NULL) |
1041 | { | |
1042 | mem_elt->next_containing_mem = first_containing_mem; | |
1043 | first_containing_mem = mem_elt; | |
1044 | } | |
fa49fd0f RK |
1045 | } |
1046 | ||
1047 | /* Subroutine of cselib_lookup. Return a value for X, which is a MEM rtx. | |
1048 | If CREATE, make a new one if we haven't seen it before. */ | |
1049 | ||
1050 | static cselib_val * | |
7080f735 | 1051 | cselib_lookup_mem (rtx x, int create) |
fa49fd0f RK |
1052 | { |
1053 | enum machine_mode mode = GET_MODE (x); | |
1054 | void **slot; | |
1055 | cselib_val *addr; | |
1056 | cselib_val *mem_elt; | |
1057 | struct elt_list *l; | |
1058 | ||
1059 | if (MEM_VOLATILE_P (x) || mode == BLKmode | |
463301c3 | 1060 | || !cselib_record_memory |
fa49fd0f RK |
1061 | || (FLOAT_MODE_P (mode) && flag_float_store)) |
1062 | return 0; | |
1063 | ||
1064 | /* Look up the value for the address. */ | |
1065 | addr = cselib_lookup (XEXP (x, 0), mode, create); | |
1066 | if (! addr) | |
1067 | return 0; | |
1068 | ||
1069 | /* Find a value that describes a value of our mode at that address. */ | |
1070 | for (l = addr->addr_list; l; l = l->next) | |
757bbef8 | 1071 | if (GET_MODE (l->elt->val_rtx) == mode) |
5847e8da AO |
1072 | { |
1073 | promote_debug_loc (l->elt->locs); | |
1074 | return l->elt; | |
1075 | } | |
fa49fd0f RK |
1076 | |
1077 | if (! create) | |
1078 | return 0; | |
1079 | ||
5440c0e7 | 1080 | mem_elt = new_cselib_val (next_uid, mode, x); |
fa49fd0f | 1081 | add_mem_for_addr (addr, mem_elt, x); |
7c514720 | 1082 | slot = htab_find_slot_with_hash (cselib_hash_table, wrap_constant (mode, x), |
5440c0e7 | 1083 | mem_elt->hash, INSERT); |
fa49fd0f RK |
1084 | *slot = mem_elt; |
1085 | return mem_elt; | |
1086 | } | |
1087 | ||
6fb5fa3c DB |
1088 | /* Search thru the possible substitutions in P. We prefer a non reg |
1089 | substitution because this allows us to expand the tree further. If | |
1090 | we find, just a reg, take the lowest regno. There may be several | |
1091 | non-reg results, we just take the first one because they will all | |
1092 | expand to the same place. */ | |
1093 | ||
b8698a0f | 1094 | static rtx |
b5b8b0ac AO |
1095 | expand_loc (struct elt_loc_list *p, struct expand_value_data *evd, |
1096 | int max_depth) | |
6fb5fa3c DB |
1097 | { |
1098 | rtx reg_result = NULL; | |
1099 | unsigned int regno = UINT_MAX; | |
1100 | struct elt_loc_list *p_in = p; | |
1101 | ||
1102 | for (; p; p = p -> next) | |
1103 | { | |
1104 | /* Avoid infinite recursion trying to expand a reg into a | |
1105 | the same reg. */ | |
b8698a0f L |
1106 | if ((REG_P (p->loc)) |
1107 | && (REGNO (p->loc) < regno) | |
b5b8b0ac | 1108 | && !bitmap_bit_p (evd->regs_active, REGNO (p->loc))) |
6fb5fa3c DB |
1109 | { |
1110 | reg_result = p->loc; | |
1111 | regno = REGNO (p->loc); | |
1112 | } | |
1113 | /* Avoid infinite recursion and do not try to expand the | |
1114 | value. */ | |
b8698a0f | 1115 | else if (GET_CODE (p->loc) == VALUE |
6fb5fa3c DB |
1116 | && CSELIB_VAL_PTR (p->loc)->locs == p_in) |
1117 | continue; | |
1118 | else if (!REG_P (p->loc)) | |
1119 | { | |
8dd5516b | 1120 | rtx result, note; |
b5b8b0ac | 1121 | if (dump_file && (dump_flags & TDF_DETAILS)) |
6fb5fa3c DB |
1122 | { |
1123 | print_inline_rtx (dump_file, p->loc, 0); | |
1124 | fprintf (dump_file, "\n"); | |
1125 | } | |
8dd5516b JJ |
1126 | if (GET_CODE (p->loc) == LO_SUM |
1127 | && GET_CODE (XEXP (p->loc, 1)) == SYMBOL_REF | |
1128 | && p->setting_insn | |
1129 | && (note = find_reg_note (p->setting_insn, REG_EQUAL, NULL_RTX)) | |
1130 | && XEXP (note, 0) == XEXP (p->loc, 1)) | |
1131 | return XEXP (p->loc, 1); | |
b5b8b0ac | 1132 | result = cselib_expand_value_rtx_1 (p->loc, evd, max_depth - 1); |
6fb5fa3c DB |
1133 | if (result) |
1134 | return result; | |
1135 | } | |
b8698a0f | 1136 | |
6fb5fa3c | 1137 | } |
b8698a0f | 1138 | |
6fb5fa3c DB |
1139 | if (regno != UINT_MAX) |
1140 | { | |
1141 | rtx result; | |
b5b8b0ac | 1142 | if (dump_file && (dump_flags & TDF_DETAILS)) |
6fb5fa3c DB |
1143 | fprintf (dump_file, "r%d\n", regno); |
1144 | ||
b5b8b0ac | 1145 | result = cselib_expand_value_rtx_1 (reg_result, evd, max_depth - 1); |
6fb5fa3c DB |
1146 | if (result) |
1147 | return result; | |
1148 | } | |
1149 | ||
b5b8b0ac | 1150 | if (dump_file && (dump_flags & TDF_DETAILS)) |
6fb5fa3c DB |
1151 | { |
1152 | if (reg_result) | |
1153 | { | |
1154 | print_inline_rtx (dump_file, reg_result, 0); | |
1155 | fprintf (dump_file, "\n"); | |
1156 | } | |
b8698a0f | 1157 | else |
6fb5fa3c DB |
1158 | fprintf (dump_file, "NULL\n"); |
1159 | } | |
1160 | return reg_result; | |
1161 | } | |
1162 | ||
1163 | ||
1164 | /* Forward substitute and expand an expression out to its roots. | |
1165 | This is the opposite of common subexpression. Because local value | |
1166 | numbering is such a weak optimization, the expanded expression is | |
1167 | pretty much unique (not from a pointer equals point of view but | |
b8698a0f | 1168 | from a tree shape point of view. |
6fb5fa3c DB |
1169 | |
1170 | This function returns NULL if the expansion fails. The expansion | |
1171 | will fail if there is no value number for one of the operands or if | |
1172 | one of the operands has been overwritten between the current insn | |
1173 | and the beginning of the basic block. For instance x has no | |
1174 | expansion in: | |
1175 | ||
1176 | r1 <- r1 + 3 | |
1177 | x <- r1 + 8 | |
1178 | ||
1179 | REGS_ACTIVE is a scratch bitmap that should be clear when passing in. | |
1180 | It is clear on return. */ | |
1181 | ||
1182 | rtx | |
1183 | cselib_expand_value_rtx (rtx orig, bitmap regs_active, int max_depth) | |
b5b8b0ac AO |
1184 | { |
1185 | struct expand_value_data evd; | |
1186 | ||
1187 | evd.regs_active = regs_active; | |
1188 | evd.callback = NULL; | |
1189 | evd.callback_arg = NULL; | |
864ddef7 | 1190 | evd.dummy = false; |
b5b8b0ac AO |
1191 | |
1192 | return cselib_expand_value_rtx_1 (orig, &evd, max_depth); | |
1193 | } | |
1194 | ||
1195 | /* Same as cselib_expand_value_rtx, but using a callback to try to | |
0b7e34d7 AO |
1196 | resolve some expressions. The CB function should return ORIG if it |
1197 | can't or does not want to deal with a certain RTX. Any other | |
1198 | return value, including NULL, will be used as the expansion for | |
1199 | VALUE, without any further changes. */ | |
b5b8b0ac AO |
1200 | |
1201 | rtx | |
1202 | cselib_expand_value_rtx_cb (rtx orig, bitmap regs_active, int max_depth, | |
1203 | cselib_expand_callback cb, void *data) | |
1204 | { | |
1205 | struct expand_value_data evd; | |
1206 | ||
1207 | evd.regs_active = regs_active; | |
1208 | evd.callback = cb; | |
1209 | evd.callback_arg = data; | |
864ddef7 | 1210 | evd.dummy = false; |
b5b8b0ac AO |
1211 | |
1212 | return cselib_expand_value_rtx_1 (orig, &evd, max_depth); | |
1213 | } | |
1214 | ||
864ddef7 JJ |
1215 | /* Similar to cselib_expand_value_rtx_cb, but no rtxs are actually copied |
1216 | or simplified. Useful to find out whether cselib_expand_value_rtx_cb | |
1217 | would return NULL or non-NULL, without allocating new rtx. */ | |
1218 | ||
1219 | bool | |
1220 | cselib_dummy_expand_value_rtx_cb (rtx orig, bitmap regs_active, int max_depth, | |
1221 | cselib_expand_callback cb, void *data) | |
1222 | { | |
1223 | struct expand_value_data evd; | |
1224 | ||
1225 | evd.regs_active = regs_active; | |
1226 | evd.callback = cb; | |
1227 | evd.callback_arg = data; | |
1228 | evd.dummy = true; | |
1229 | ||
1230 | return cselib_expand_value_rtx_1 (orig, &evd, max_depth) != NULL; | |
1231 | } | |
1232 | ||
0b7e34d7 AO |
1233 | /* Internal implementation of cselib_expand_value_rtx and |
1234 | cselib_expand_value_rtx_cb. */ | |
1235 | ||
b5b8b0ac AO |
1236 | static rtx |
1237 | cselib_expand_value_rtx_1 (rtx orig, struct expand_value_data *evd, | |
1238 | int max_depth) | |
6fb5fa3c DB |
1239 | { |
1240 | rtx copy, scopy; | |
1241 | int i, j; | |
1242 | RTX_CODE code; | |
1243 | const char *format_ptr; | |
8dd5516b | 1244 | enum machine_mode mode; |
6fb5fa3c DB |
1245 | |
1246 | code = GET_CODE (orig); | |
1247 | ||
1248 | /* For the context of dse, if we end up expand into a huge tree, we | |
1249 | will not have a useful address, so we might as well just give up | |
1250 | quickly. */ | |
1251 | if (max_depth <= 0) | |
1252 | return NULL; | |
1253 | ||
1254 | switch (code) | |
1255 | { | |
1256 | case REG: | |
1257 | { | |
1258 | struct elt_list *l = REG_VALUES (REGNO (orig)); | |
1259 | ||
1260 | if (l && l->elt == NULL) | |
1261 | l = l->next; | |
1262 | for (; l; l = l->next) | |
1263 | if (GET_MODE (l->elt->val_rtx) == GET_MODE (orig)) | |
1264 | { | |
1265 | rtx result; | |
1266 | int regno = REGNO (orig); | |
b8698a0f | 1267 | |
6fb5fa3c | 1268 | /* The only thing that we are not willing to do (this |
6ed3da00 | 1269 | is requirement of dse and if others potential uses |
6fb5fa3c DB |
1270 | need this function we should add a parm to control |
1271 | it) is that we will not substitute the | |
1272 | STACK_POINTER_REGNUM, FRAME_POINTER or the | |
1273 | HARD_FRAME_POINTER. | |
1274 | ||
cea618ac | 1275 | These expansions confuses the code that notices that |
6fb5fa3c DB |
1276 | stores into the frame go dead at the end of the |
1277 | function and that the frame is not effected by calls | |
1278 | to subroutines. If you allow the | |
1279 | STACK_POINTER_REGNUM substitution, then dse will | |
1280 | think that parameter pushing also goes dead which is | |
1281 | wrong. If you allow the FRAME_POINTER or the | |
1282 | HARD_FRAME_POINTER then you lose the opportunity to | |
1283 | make the frame assumptions. */ | |
1284 | if (regno == STACK_POINTER_REGNUM | |
1285 | || regno == FRAME_POINTER_REGNUM | |
1286 | || regno == HARD_FRAME_POINTER_REGNUM) | |
1287 | return orig; | |
1288 | ||
b5b8b0ac | 1289 | bitmap_set_bit (evd->regs_active, regno); |
6fb5fa3c | 1290 | |
b5b8b0ac | 1291 | if (dump_file && (dump_flags & TDF_DETAILS)) |
6fb5fa3c DB |
1292 | fprintf (dump_file, "expanding: r%d into: ", regno); |
1293 | ||
b5b8b0ac AO |
1294 | result = expand_loc (l->elt->locs, evd, max_depth); |
1295 | bitmap_clear_bit (evd->regs_active, regno); | |
6fb5fa3c DB |
1296 | |
1297 | if (result) | |
1298 | return result; | |
b8698a0f | 1299 | else |
6fb5fa3c DB |
1300 | return orig; |
1301 | } | |
1302 | } | |
b8698a0f | 1303 | |
6fb5fa3c DB |
1304 | case CONST_INT: |
1305 | case CONST_DOUBLE: | |
1306 | case CONST_VECTOR: | |
1307 | case SYMBOL_REF: | |
1308 | case CODE_LABEL: | |
1309 | case PC: | |
1310 | case CC0: | |
1311 | case SCRATCH: | |
1312 | /* SCRATCH must be shared because they represent distinct values. */ | |
1313 | return orig; | |
1314 | case CLOBBER: | |
1315 | if (REG_P (XEXP (orig, 0)) && HARD_REGISTER_NUM_P (REGNO (XEXP (orig, 0)))) | |
1316 | return orig; | |
1317 | break; | |
1318 | ||
1319 | case CONST: | |
1320 | if (shared_const_p (orig)) | |
1321 | return orig; | |
1322 | break; | |
1323 | ||
8dd5516b | 1324 | case SUBREG: |
6fb5fa3c | 1325 | { |
0b7e34d7 AO |
1326 | rtx subreg; |
1327 | ||
1328 | if (evd->callback) | |
1329 | { | |
1330 | subreg = evd->callback (orig, evd->regs_active, max_depth, | |
1331 | evd->callback_arg); | |
1332 | if (subreg != orig) | |
1333 | return subreg; | |
1334 | } | |
1335 | ||
1336 | subreg = cselib_expand_value_rtx_1 (SUBREG_REG (orig), evd, | |
1337 | max_depth - 1); | |
8dd5516b JJ |
1338 | if (!subreg) |
1339 | return NULL; | |
1340 | scopy = simplify_gen_subreg (GET_MODE (orig), subreg, | |
1341 | GET_MODE (SUBREG_REG (orig)), | |
1342 | SUBREG_BYTE (orig)); | |
0b7e34d7 AO |
1343 | if (scopy == NULL |
1344 | || (GET_CODE (scopy) == SUBREG | |
1345 | && !REG_P (SUBREG_REG (scopy)) | |
1346 | && !MEM_P (SUBREG_REG (scopy)))) | |
1347 | return NULL; | |
1348 | ||
8dd5516b | 1349 | return scopy; |
6fb5fa3c | 1350 | } |
8dd5516b JJ |
1351 | |
1352 | case VALUE: | |
b5b8b0ac AO |
1353 | { |
1354 | rtx result; | |
0b7e34d7 | 1355 | |
b5b8b0ac AO |
1356 | if (dump_file && (dump_flags & TDF_DETAILS)) |
1357 | { | |
1358 | fputs ("\nexpanding ", dump_file); | |
1359 | print_rtl_single (dump_file, orig); | |
1360 | fputs (" into...", dump_file); | |
1361 | } | |
8dd5516b | 1362 | |
0b7e34d7 | 1363 | if (evd->callback) |
b5b8b0ac AO |
1364 | { |
1365 | result = evd->callback (orig, evd->regs_active, max_depth, | |
1366 | evd->callback_arg); | |
0b7e34d7 AO |
1367 | |
1368 | if (result != orig) | |
1369 | return result; | |
b5b8b0ac | 1370 | } |
8dd5516b | 1371 | |
0b7e34d7 | 1372 | result = expand_loc (CSELIB_VAL_PTR (orig)->locs, evd, max_depth); |
b5b8b0ac AO |
1373 | return result; |
1374 | } | |
0ca5af51 AO |
1375 | |
1376 | case DEBUG_EXPR: | |
1377 | if (evd->callback) | |
1378 | return evd->callback (orig, evd->regs_active, max_depth, | |
1379 | evd->callback_arg); | |
1380 | return orig; | |
1381 | ||
6fb5fa3c DB |
1382 | default: |
1383 | break; | |
1384 | } | |
1385 | ||
1386 | /* Copy the various flags, fields, and other information. We assume | |
1387 | that all fields need copying, and then clear the fields that should | |
1388 | not be copied. That is the sensible default behavior, and forces | |
1389 | us to explicitly document why we are *not* copying a flag. */ | |
864ddef7 JJ |
1390 | if (evd->dummy) |
1391 | copy = NULL; | |
1392 | else | |
1393 | copy = shallow_copy_rtx (orig); | |
6fb5fa3c | 1394 | |
8dd5516b | 1395 | format_ptr = GET_RTX_FORMAT (code); |
6fb5fa3c | 1396 | |
8dd5516b | 1397 | for (i = 0; i < GET_RTX_LENGTH (code); i++) |
6fb5fa3c DB |
1398 | switch (*format_ptr++) |
1399 | { | |
1400 | case 'e': | |
1401 | if (XEXP (orig, i) != NULL) | |
1402 | { | |
b5b8b0ac AO |
1403 | rtx result = cselib_expand_value_rtx_1 (XEXP (orig, i), evd, |
1404 | max_depth - 1); | |
6fb5fa3c DB |
1405 | if (!result) |
1406 | return NULL; | |
864ddef7 JJ |
1407 | if (copy) |
1408 | XEXP (copy, i) = result; | |
6fb5fa3c DB |
1409 | } |
1410 | break; | |
1411 | ||
1412 | case 'E': | |
1413 | case 'V': | |
1414 | if (XVEC (orig, i) != NULL) | |
1415 | { | |
864ddef7 JJ |
1416 | if (copy) |
1417 | XVEC (copy, i) = rtvec_alloc (XVECLEN (orig, i)); | |
1418 | for (j = 0; j < XVECLEN (orig, i); j++) | |
6fb5fa3c | 1419 | { |
b5b8b0ac AO |
1420 | rtx result = cselib_expand_value_rtx_1 (XVECEXP (orig, i, j), |
1421 | evd, max_depth - 1); | |
6fb5fa3c DB |
1422 | if (!result) |
1423 | return NULL; | |
864ddef7 JJ |
1424 | if (copy) |
1425 | XVECEXP (copy, i, j) = result; | |
6fb5fa3c DB |
1426 | } |
1427 | } | |
1428 | break; | |
1429 | ||
1430 | case 't': | |
1431 | case 'w': | |
1432 | case 'i': | |
1433 | case 's': | |
1434 | case 'S': | |
1435 | case 'T': | |
1436 | case 'u': | |
1437 | case 'B': | |
1438 | case '0': | |
1439 | /* These are left unchanged. */ | |
1440 | break; | |
1441 | ||
1442 | default: | |
1443 | gcc_unreachable (); | |
1444 | } | |
1445 | ||
864ddef7 JJ |
1446 | if (evd->dummy) |
1447 | return orig; | |
1448 | ||
8dd5516b JJ |
1449 | mode = GET_MODE (copy); |
1450 | /* If an operand has been simplified into CONST_INT, which doesn't | |
1451 | have a mode and the mode isn't derivable from whole rtx's mode, | |
1452 | try simplify_*_operation first with mode from original's operand | |
1453 | and as a fallback wrap CONST_INT into gen_rtx_CONST. */ | |
1454 | scopy = copy; | |
1455 | switch (GET_RTX_CLASS (code)) | |
1456 | { | |
1457 | case RTX_UNARY: | |
1458 | if (CONST_INT_P (XEXP (copy, 0)) | |
1459 | && GET_MODE (XEXP (orig, 0)) != VOIDmode) | |
1460 | { | |
1461 | scopy = simplify_unary_operation (code, mode, XEXP (copy, 0), | |
1462 | GET_MODE (XEXP (orig, 0))); | |
1463 | if (scopy) | |
1464 | return scopy; | |
1465 | } | |
1466 | break; | |
1467 | case RTX_COMM_ARITH: | |
1468 | case RTX_BIN_ARITH: | |
1469 | /* These expressions can derive operand modes from the whole rtx's mode. */ | |
1470 | break; | |
1471 | case RTX_TERNARY: | |
1472 | case RTX_BITFIELD_OPS: | |
1473 | if (CONST_INT_P (XEXP (copy, 0)) | |
1474 | && GET_MODE (XEXP (orig, 0)) != VOIDmode) | |
1475 | { | |
1476 | scopy = simplify_ternary_operation (code, mode, | |
1477 | GET_MODE (XEXP (orig, 0)), | |
1478 | XEXP (copy, 0), XEXP (copy, 1), | |
1479 | XEXP (copy, 2)); | |
1480 | if (scopy) | |
1481 | return scopy; | |
1482 | } | |
1483 | break; | |
1484 | case RTX_COMPARE: | |
1485 | case RTX_COMM_COMPARE: | |
1486 | if (CONST_INT_P (XEXP (copy, 0)) | |
1487 | && GET_MODE (XEXP (copy, 1)) == VOIDmode | |
1488 | && (GET_MODE (XEXP (orig, 0)) != VOIDmode | |
1489 | || GET_MODE (XEXP (orig, 1)) != VOIDmode)) | |
1490 | { | |
1491 | scopy = simplify_relational_operation (code, mode, | |
1492 | (GET_MODE (XEXP (orig, 0)) | |
1493 | != VOIDmode) | |
1494 | ? GET_MODE (XEXP (orig, 0)) | |
1495 | : GET_MODE (XEXP (orig, 1)), | |
1496 | XEXP (copy, 0), | |
1497 | XEXP (copy, 1)); | |
1498 | if (scopy) | |
1499 | return scopy; | |
1500 | } | |
1501 | break; | |
1502 | default: | |
1503 | break; | |
1504 | } | |
6fb5fa3c DB |
1505 | scopy = simplify_rtx (copy); |
1506 | if (scopy) | |
3af4ba41 | 1507 | return scopy; |
6fb5fa3c DB |
1508 | return copy; |
1509 | } | |
1510 | ||
fa49fd0f RK |
1511 | /* Walk rtx X and replace all occurrences of REG and MEM subexpressions |
1512 | with VALUE expressions. This way, it becomes independent of changes | |
1513 | to registers and memory. | |
1514 | X isn't actually modified; if modifications are needed, new rtl is | |
1515 | allocated. However, the return value can share rtl with X. */ | |
1516 | ||
91700444 | 1517 | rtx |
7080f735 | 1518 | cselib_subst_to_values (rtx x) |
fa49fd0f RK |
1519 | { |
1520 | enum rtx_code code = GET_CODE (x); | |
1521 | const char *fmt = GET_RTX_FORMAT (code); | |
1522 | cselib_val *e; | |
1523 | struct elt_list *l; | |
1524 | rtx copy = x; | |
1525 | int i; | |
1526 | ||
1527 | switch (code) | |
1528 | { | |
1529 | case REG: | |
60fa6660 AO |
1530 | l = REG_VALUES (REGNO (x)); |
1531 | if (l && l->elt == NULL) | |
1532 | l = l->next; | |
1533 | for (; l; l = l->next) | |
757bbef8 SB |
1534 | if (GET_MODE (l->elt->val_rtx) == GET_MODE (x)) |
1535 | return l->elt->val_rtx; | |
fa49fd0f | 1536 | |
341c100f | 1537 | gcc_unreachable (); |
fa49fd0f RK |
1538 | |
1539 | case MEM: | |
1540 | e = cselib_lookup_mem (x, 0); | |
1541 | if (! e) | |
91700444 BS |
1542 | { |
1543 | /* This happens for autoincrements. Assign a value that doesn't | |
1544 | match any other. */ | |
5440c0e7 | 1545 | e = new_cselib_val (next_uid, GET_MODE (x), x); |
91700444 | 1546 | } |
757bbef8 | 1547 | return e->val_rtx; |
fa49fd0f | 1548 | |
fa49fd0f | 1549 | case CONST_DOUBLE: |
69ef87e2 | 1550 | case CONST_VECTOR: |
fa49fd0f | 1551 | case CONST_INT: |
091a3ac7 | 1552 | case CONST_FIXED: |
fa49fd0f RK |
1553 | return x; |
1554 | ||
91700444 BS |
1555 | case POST_INC: |
1556 | case PRE_INC: | |
1557 | case POST_DEC: | |
1558 | case PRE_DEC: | |
1559 | case POST_MODIFY: | |
1560 | case PRE_MODIFY: | |
5440c0e7 | 1561 | e = new_cselib_val (next_uid, GET_MODE (x), x); |
757bbef8 | 1562 | return e->val_rtx; |
7080f735 | 1563 | |
fa49fd0f RK |
1564 | default: |
1565 | break; | |
1566 | } | |
1567 | ||
1568 | for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--) | |
1569 | { | |
1570 | if (fmt[i] == 'e') | |
1571 | { | |
1572 | rtx t = cselib_subst_to_values (XEXP (x, i)); | |
1573 | ||
bd7960b1 RS |
1574 | if (t != XEXP (x, i)) |
1575 | { | |
1576 | if (x == copy) | |
1577 | copy = shallow_copy_rtx (x); | |
1578 | XEXP (copy, i) = t; | |
1579 | } | |
fa49fd0f RK |
1580 | } |
1581 | else if (fmt[i] == 'E') | |
1582 | { | |
bd7960b1 | 1583 | int j; |
fa49fd0f RK |
1584 | |
1585 | for (j = 0; j < XVECLEN (x, i); j++) | |
1586 | { | |
1587 | rtx t = cselib_subst_to_values (XVECEXP (x, i, j)); | |
1588 | ||
bd7960b1 | 1589 | if (t != XVECEXP (x, i, j)) |
fa49fd0f | 1590 | { |
bd7960b1 RS |
1591 | if (XVEC (x, i) == XVEC (copy, i)) |
1592 | { | |
1593 | if (x == copy) | |
1594 | copy = shallow_copy_rtx (x); | |
1595 | XVEC (copy, i) = shallow_copy_rtvec (XVEC (x, i)); | |
1596 | } | |
1597 | XVECEXP (copy, i, j) = t; | |
fa49fd0f | 1598 | } |
fa49fd0f RK |
1599 | } |
1600 | } | |
1601 | } | |
1602 | ||
1603 | return copy; | |
1604 | } | |
1605 | ||
1606 | /* Look up the rtl expression X in our tables and return the value it has. | |
1607 | If CREATE is zero, we return NULL if we don't know the value. Otherwise, | |
1608 | we create a new one if possible, using mode MODE if X doesn't have a mode | |
1609 | (i.e. because it's a constant). */ | |
1610 | ||
5847e8da AO |
1611 | static cselib_val * |
1612 | cselib_lookup_1 (rtx x, enum machine_mode mode, int create) | |
fa49fd0f RK |
1613 | { |
1614 | void **slot; | |
1615 | cselib_val *e; | |
1616 | unsigned int hashval; | |
1617 | ||
1618 | if (GET_MODE (x) != VOIDmode) | |
1619 | mode = GET_MODE (x); | |
1620 | ||
1621 | if (GET_CODE (x) == VALUE) | |
1622 | return CSELIB_VAL_PTR (x); | |
1623 | ||
f8cfc6aa | 1624 | if (REG_P (x)) |
fa49fd0f RK |
1625 | { |
1626 | struct elt_list *l; | |
1627 | unsigned int i = REGNO (x); | |
1628 | ||
60fa6660 AO |
1629 | l = REG_VALUES (i); |
1630 | if (l && l->elt == NULL) | |
1631 | l = l->next; | |
1632 | for (; l; l = l->next) | |
757bbef8 | 1633 | if (mode == GET_MODE (l->elt->val_rtx)) |
5847e8da AO |
1634 | { |
1635 | promote_debug_loc (l->elt->locs); | |
1636 | return l->elt; | |
1637 | } | |
fa49fd0f RK |
1638 | |
1639 | if (! create) | |
5847e8da | 1640 | return 0; |
fa49fd0f | 1641 | |
31825e57 DM |
1642 | if (i < FIRST_PSEUDO_REGISTER) |
1643 | { | |
66fd46b6 | 1644 | unsigned int n = hard_regno_nregs[i][mode]; |
31825e57 DM |
1645 | |
1646 | if (n > max_value_regs) | |
1647 | max_value_regs = n; | |
1648 | } | |
1649 | ||
5440c0e7 | 1650 | e = new_cselib_val (next_uid, GET_MODE (x), x); |
fa49fd0f RK |
1651 | e->locs = new_elt_loc_list (e->locs, x); |
1652 | if (REG_VALUES (i) == 0) | |
60fa6660 AO |
1653 | { |
1654 | /* Maintain the invariant that the first entry of | |
1655 | REG_VALUES, if present, must be the value used to set the | |
1656 | register, or NULL. */ | |
6790d1ab | 1657 | used_regs[n_used_regs++] = i; |
60fa6660 AO |
1658 | REG_VALUES (i) = new_elt_list (REG_VALUES (i), NULL); |
1659 | } | |
1660 | REG_VALUES (i)->next = new_elt_list (REG_VALUES (i)->next, e); | |
5440c0e7 | 1661 | slot = htab_find_slot_with_hash (cselib_hash_table, x, e->hash, INSERT); |
fa49fd0f | 1662 | *slot = e; |
5847e8da | 1663 | return e; |
fa49fd0f RK |
1664 | } |
1665 | ||
3c0cb5de | 1666 | if (MEM_P (x)) |
5847e8da | 1667 | return cselib_lookup_mem (x, create); |
fa49fd0f | 1668 | |
29c1846b | 1669 | hashval = cselib_hash_rtx (x, create); |
fa49fd0f RK |
1670 | /* Can't even create if hashing is not possible. */ |
1671 | if (! hashval) | |
5847e8da | 1672 | return 0; |
fa49fd0f | 1673 | |
7c514720 | 1674 | slot = htab_find_slot_with_hash (cselib_hash_table, wrap_constant (mode, x), |
fa49fd0f RK |
1675 | hashval, create ? INSERT : NO_INSERT); |
1676 | if (slot == 0) | |
5847e8da | 1677 | return 0; |
fa49fd0f RK |
1678 | |
1679 | e = (cselib_val *) *slot; | |
1680 | if (e) | |
5847e8da | 1681 | return e; |
fa49fd0f | 1682 | |
b5b8b0ac | 1683 | e = new_cselib_val (hashval, mode, x); |
fa49fd0f RK |
1684 | |
1685 | /* We have to fill the slot before calling cselib_subst_to_values: | |
1686 | the hash table is inconsistent until we do so, and | |
1687 | cselib_subst_to_values will need to do lookups. */ | |
1688 | *slot = (void *) e; | |
1689 | e->locs = new_elt_loc_list (e->locs, cselib_subst_to_values (x)); | |
5847e8da AO |
1690 | return e; |
1691 | } | |
1692 | ||
1693 | /* Wrapper for cselib_lookup, that indicates X is in INSN. */ | |
1694 | ||
1695 | cselib_val * | |
1696 | cselib_lookup_from_insn (rtx x, enum machine_mode mode, | |
1697 | int create, rtx insn) | |
1698 | { | |
1699 | cselib_val *ret; | |
1700 | ||
1701 | gcc_assert (!cselib_current_insn); | |
1702 | cselib_current_insn = insn; | |
1703 | ||
1704 | ret = cselib_lookup (x, mode, create); | |
1705 | ||
1706 | cselib_current_insn = NULL; | |
1707 | ||
1708 | return ret; | |
1709 | } | |
1710 | ||
1711 | /* Wrapper for cselib_lookup_1, that logs the lookup result and | |
1712 | maintains invariants related with debug insns. */ | |
1713 | ||
1714 | cselib_val * | |
1715 | cselib_lookup (rtx x, enum machine_mode mode, int create) | |
1716 | { | |
1717 | cselib_val *ret = cselib_lookup_1 (x, mode, create); | |
1718 | ||
1719 | /* ??? Should we return NULL if we're not to create an entry, the | |
1720 | found loc is a debug loc and cselib_current_insn is not DEBUG? | |
1721 | If so, we should also avoid converting val to non-DEBUG; probably | |
1722 | easiest setting cselib_current_insn to NULL before the call | |
1723 | above. */ | |
1724 | ||
1725 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
1726 | { | |
1727 | fputs ("cselib lookup ", dump_file); | |
1728 | print_inline_rtx (dump_file, x, 2); | |
1729 | fprintf (dump_file, " => %u:%u\n", | |
1730 | ret ? ret->uid : 0, | |
1731 | ret ? ret->hash : 0); | |
1732 | } | |
1733 | ||
1734 | return ret; | |
fa49fd0f RK |
1735 | } |
1736 | ||
1737 | /* Invalidate any entries in reg_values that overlap REGNO. This is called | |
1738 | if REGNO is changing. MODE is the mode of the assignment to REGNO, which | |
1739 | is used to determine how many hard registers are being changed. If MODE | |
1740 | is VOIDmode, then only REGNO is being changed; this is used when | |
1741 | invalidating call clobbered registers across a call. */ | |
1742 | ||
1743 | static void | |
7080f735 | 1744 | cselib_invalidate_regno (unsigned int regno, enum machine_mode mode) |
fa49fd0f RK |
1745 | { |
1746 | unsigned int endregno; | |
1747 | unsigned int i; | |
1748 | ||
1749 | /* If we see pseudos after reload, something is _wrong_. */ | |
341c100f NS |
1750 | gcc_assert (!reload_completed || regno < FIRST_PSEUDO_REGISTER |
1751 | || reg_renumber[regno] < 0); | |
fa49fd0f RK |
1752 | |
1753 | /* Determine the range of registers that must be invalidated. For | |
1754 | pseudos, only REGNO is affected. For hard regs, we must take MODE | |
1755 | into account, and we must also invalidate lower register numbers | |
1756 | if they contain values that overlap REGNO. */ | |
291aac59 | 1757 | if (regno < FIRST_PSEUDO_REGISTER) |
31825e57 | 1758 | { |
341c100f | 1759 | gcc_assert (mode != VOIDmode); |
7080f735 | 1760 | |
31825e57 DM |
1761 | if (regno < max_value_regs) |
1762 | i = 0; | |
1763 | else | |
1764 | i = regno - max_value_regs; | |
fa49fd0f | 1765 | |
09e18274 | 1766 | endregno = end_hard_regno (mode, regno); |
31825e57 DM |
1767 | } |
1768 | else | |
1769 | { | |
1770 | i = regno; | |
1771 | endregno = regno + 1; | |
1772 | } | |
1773 | ||
1774 | for (; i < endregno; i++) | |
fa49fd0f RK |
1775 | { |
1776 | struct elt_list **l = ®_VALUES (i); | |
1777 | ||
1778 | /* Go through all known values for this reg; if it overlaps the range | |
1779 | we're invalidating, remove the value. */ | |
1780 | while (*l) | |
1781 | { | |
1782 | cselib_val *v = (*l)->elt; | |
5847e8da AO |
1783 | bool had_locs; |
1784 | rtx setting_insn; | |
fa49fd0f RK |
1785 | struct elt_loc_list **p; |
1786 | unsigned int this_last = i; | |
1787 | ||
60fa6660 | 1788 | if (i < FIRST_PSEUDO_REGISTER && v != NULL) |
09e18274 | 1789 | this_last = end_hard_regno (GET_MODE (v->val_rtx), i) - 1; |
fa49fd0f | 1790 | |
9de9cbaf JJ |
1791 | if (this_last < regno || v == NULL |
1792 | || (v == cfa_base_preserved_val | |
1793 | && i == cfa_base_preserved_regno)) | |
fa49fd0f RK |
1794 | { |
1795 | l = &(*l)->next; | |
1796 | continue; | |
1797 | } | |
1798 | ||
1799 | /* We have an overlap. */ | |
60fa6660 AO |
1800 | if (*l == REG_VALUES (i)) |
1801 | { | |
1802 | /* Maintain the invariant that the first entry of | |
1803 | REG_VALUES, if present, must be the value used to set | |
1804 | the register, or NULL. This is also nice because | |
1805 | then we won't push the same regno onto user_regs | |
1806 | multiple times. */ | |
1807 | (*l)->elt = NULL; | |
1808 | l = &(*l)->next; | |
1809 | } | |
1810 | else | |
1811 | unchain_one_elt_list (l); | |
fa49fd0f | 1812 | |
5847e8da AO |
1813 | had_locs = v->locs != NULL; |
1814 | setting_insn = v->locs ? v->locs->setting_insn : NULL; | |
1815 | ||
fa49fd0f RK |
1816 | /* Now, we clear the mapping from value to reg. It must exist, so |
1817 | this code will crash intentionally if it doesn't. */ | |
1818 | for (p = &v->locs; ; p = &(*p)->next) | |
1819 | { | |
1820 | rtx x = (*p)->loc; | |
1821 | ||
f8cfc6aa | 1822 | if (REG_P (x) && REGNO (x) == i) |
fa49fd0f RK |
1823 | { |
1824 | unchain_one_elt_loc_list (p); | |
1825 | break; | |
1826 | } | |
1827 | } | |
5847e8da AO |
1828 | |
1829 | if (had_locs && v->locs == 0 && !PRESERVED_VALUE_P (v->val_rtx)) | |
1830 | { | |
1831 | if (setting_insn && DEBUG_INSN_P (setting_insn)) | |
1832 | n_useless_debug_values++; | |
1833 | else | |
1834 | n_useless_values++; | |
1835 | } | |
fa49fd0f RK |
1836 | } |
1837 | } | |
1838 | } | |
9ddb66ca JH |
1839 | \f |
1840 | /* Return 1 if X has a value that can vary even between two | |
1841 | executions of the program. 0 means X can be compared reliably | |
1842 | against certain constants or near-constants. */ | |
fa49fd0f | 1843 | |
4f588890 KG |
1844 | static bool |
1845 | cselib_rtx_varies_p (const_rtx x ATTRIBUTE_UNUSED, bool from_alias ATTRIBUTE_UNUSED) | |
fa49fd0f | 1846 | { |
9ddb66ca JH |
1847 | /* We actually don't need to verify very hard. This is because |
1848 | if X has actually changed, we invalidate the memory anyway, | |
1849 | so assume that all common memory addresses are | |
1850 | invariant. */ | |
fa49fd0f RK |
1851 | return 0; |
1852 | } | |
1853 | ||
7101fb18 JH |
1854 | /* Invalidate any locations in the table which are changed because of a |
1855 | store to MEM_RTX. If this is called because of a non-const call | |
1856 | instruction, MEM_RTX is (mem:BLK const0_rtx). */ | |
fa49fd0f | 1857 | |
7101fb18 | 1858 | static void |
7080f735 | 1859 | cselib_invalidate_mem (rtx mem_rtx) |
fa49fd0f | 1860 | { |
7101fb18 | 1861 | cselib_val **vp, *v, *next; |
c65ecebc | 1862 | int num_mems = 0; |
9ddb66ca JH |
1863 | rtx mem_addr; |
1864 | ||
1865 | mem_addr = canon_rtx (get_addr (XEXP (mem_rtx, 0))); | |
1866 | mem_rtx = canon_rtx (mem_rtx); | |
fa49fd0f | 1867 | |
7101fb18 JH |
1868 | vp = &first_containing_mem; |
1869 | for (v = *vp; v != &dummy_val; v = next) | |
fa49fd0f | 1870 | { |
7101fb18 JH |
1871 | bool has_mem = false; |
1872 | struct elt_loc_list **p = &v->locs; | |
5847e8da AO |
1873 | bool had_locs = v->locs != NULL; |
1874 | rtx setting_insn = v->locs ? v->locs->setting_insn : NULL; | |
fa49fd0f | 1875 | |
7101fb18 | 1876 | while (*p) |
fa49fd0f | 1877 | { |
7101fb18 JH |
1878 | rtx x = (*p)->loc; |
1879 | cselib_val *addr; | |
1880 | struct elt_list **mem_chain; | |
1881 | ||
1882 | /* MEMs may occur in locations only at the top level; below | |
1883 | that every MEM or REG is substituted by its VALUE. */ | |
3c0cb5de | 1884 | if (!MEM_P (x)) |
fa49fd0f | 1885 | { |
7101fb18 JH |
1886 | p = &(*p)->next; |
1887 | continue; | |
1888 | } | |
c65ecebc | 1889 | if (num_mems < PARAM_VALUE (PARAM_MAX_CSELIB_MEMORY_LOCATIONS) |
9ddb66ca | 1890 | && ! canon_true_dependence (mem_rtx, GET_MODE (mem_rtx), mem_addr, |
6216f94e | 1891 | x, NULL_RTX, cselib_rtx_varies_p)) |
7101fb18 JH |
1892 | { |
1893 | has_mem = true; | |
c65ecebc | 1894 | num_mems++; |
7101fb18 JH |
1895 | p = &(*p)->next; |
1896 | continue; | |
fa49fd0f RK |
1897 | } |
1898 | ||
7101fb18 JH |
1899 | /* This one overlaps. */ |
1900 | /* We must have a mapping from this MEM's address to the | |
1901 | value (E). Remove that, too. */ | |
1902 | addr = cselib_lookup (XEXP (x, 0), VOIDmode, 0); | |
1903 | mem_chain = &addr->addr_list; | |
1904 | for (;;) | |
1905 | { | |
1906 | if ((*mem_chain)->elt == v) | |
1907 | { | |
1908 | unchain_one_elt_list (mem_chain); | |
1909 | break; | |
1910 | } | |
fa49fd0f | 1911 | |
7101fb18 JH |
1912 | mem_chain = &(*mem_chain)->next; |
1913 | } | |
fa49fd0f | 1914 | |
7101fb18 JH |
1915 | unchain_one_elt_loc_list (p); |
1916 | } | |
fa49fd0f | 1917 | |
b5b8b0ac | 1918 | if (had_locs && v->locs == 0 && !PRESERVED_VALUE_P (v->val_rtx)) |
5847e8da AO |
1919 | { |
1920 | if (setting_insn && DEBUG_INSN_P (setting_insn)) | |
1921 | n_useless_debug_values++; | |
1922 | else | |
1923 | n_useless_values++; | |
1924 | } | |
fa49fd0f | 1925 | |
7101fb18 JH |
1926 | next = v->next_containing_mem; |
1927 | if (has_mem) | |
1928 | { | |
1929 | *vp = v; | |
1930 | vp = &(*vp)->next_containing_mem; | |
1931 | } | |
1932 | else | |
1933 | v->next_containing_mem = NULL; | |
1934 | } | |
1935 | *vp = &dummy_val; | |
fa49fd0f RK |
1936 | } |
1937 | ||
0d87c765 | 1938 | /* Invalidate DEST, which is being assigned to or clobbered. */ |
fa49fd0f | 1939 | |
0d87c765 RH |
1940 | void |
1941 | cselib_invalidate_rtx (rtx dest) | |
fa49fd0f | 1942 | { |
46d096a3 SB |
1943 | while (GET_CODE (dest) == SUBREG |
1944 | || GET_CODE (dest) == ZERO_EXTRACT | |
1945 | || GET_CODE (dest) == STRICT_LOW_PART) | |
fa49fd0f RK |
1946 | dest = XEXP (dest, 0); |
1947 | ||
f8cfc6aa | 1948 | if (REG_P (dest)) |
fa49fd0f | 1949 | cselib_invalidate_regno (REGNO (dest), GET_MODE (dest)); |
3c0cb5de | 1950 | else if (MEM_P (dest)) |
fa49fd0f RK |
1951 | cselib_invalidate_mem (dest); |
1952 | ||
1953 | /* Some machines don't define AUTO_INC_DEC, but they still use push | |
1954 | instructions. We need to catch that case here in order to | |
1955 | invalidate the stack pointer correctly. Note that invalidating | |
1956 | the stack pointer is different from invalidating DEST. */ | |
1957 | if (push_operand (dest, GET_MODE (dest))) | |
0d87c765 RH |
1958 | cselib_invalidate_rtx (stack_pointer_rtx); |
1959 | } | |
1960 | ||
1961 | /* A wrapper for cselib_invalidate_rtx to be called via note_stores. */ | |
1962 | ||
1963 | static void | |
7bc980e1 | 1964 | cselib_invalidate_rtx_note_stores (rtx dest, const_rtx ignore ATTRIBUTE_UNUSED, |
0d87c765 RH |
1965 | void *data ATTRIBUTE_UNUSED) |
1966 | { | |
1967 | cselib_invalidate_rtx (dest); | |
fa49fd0f RK |
1968 | } |
1969 | ||
1970 | /* Record the result of a SET instruction. DEST is being set; the source | |
1971 | contains the value described by SRC_ELT. If DEST is a MEM, DEST_ADDR_ELT | |
1972 | describes its address. */ | |
1973 | ||
1974 | static void | |
7080f735 | 1975 | cselib_record_set (rtx dest, cselib_val *src_elt, cselib_val *dest_addr_elt) |
fa49fd0f | 1976 | { |
f8cfc6aa | 1977 | int dreg = REG_P (dest) ? (int) REGNO (dest) : -1; |
fa49fd0f RK |
1978 | |
1979 | if (src_elt == 0 || side_effects_p (dest)) | |
1980 | return; | |
1981 | ||
1982 | if (dreg >= 0) | |
1983 | { | |
31825e57 DM |
1984 | if (dreg < FIRST_PSEUDO_REGISTER) |
1985 | { | |
66fd46b6 | 1986 | unsigned int n = hard_regno_nregs[dreg][GET_MODE (dest)]; |
31825e57 DM |
1987 | |
1988 | if (n > max_value_regs) | |
1989 | max_value_regs = n; | |
1990 | } | |
1991 | ||
60fa6660 AO |
1992 | if (REG_VALUES (dreg) == 0) |
1993 | { | |
6790d1ab | 1994 | used_regs[n_used_regs++] = dreg; |
60fa6660 AO |
1995 | REG_VALUES (dreg) = new_elt_list (REG_VALUES (dreg), src_elt); |
1996 | } | |
1997 | else | |
1998 | { | |
341c100f NS |
1999 | /* The register should have been invalidated. */ |
2000 | gcc_assert (REG_VALUES (dreg)->elt == 0); | |
2001 | REG_VALUES (dreg)->elt = src_elt; | |
60fa6660 AO |
2002 | } |
2003 | ||
b5b8b0ac | 2004 | if (src_elt->locs == 0 && !PRESERVED_VALUE_P (src_elt->val_rtx)) |
fa49fd0f RK |
2005 | n_useless_values--; |
2006 | src_elt->locs = new_elt_loc_list (src_elt->locs, dest); | |
2007 | } | |
3c0cb5de | 2008 | else if (MEM_P (dest) && dest_addr_elt != 0 |
463301c3 | 2009 | && cselib_record_memory) |
fa49fd0f | 2010 | { |
b5b8b0ac | 2011 | if (src_elt->locs == 0 && !PRESERVED_VALUE_P (src_elt->val_rtx)) |
fa49fd0f RK |
2012 | n_useless_values--; |
2013 | add_mem_for_addr (dest_addr_elt, src_elt, dest); | |
2014 | } | |
2015 | } | |
2016 | ||
fa49fd0f RK |
2017 | /* There is no good way to determine how many elements there can be |
2018 | in a PARALLEL. Since it's fairly cheap, use a really large number. */ | |
2019 | #define MAX_SETS (FIRST_PSEUDO_REGISTER * 2) | |
2020 | ||
2021 | /* Record the effects of any sets in INSN. */ | |
2022 | static void | |
7080f735 | 2023 | cselib_record_sets (rtx insn) |
fa49fd0f RK |
2024 | { |
2025 | int n_sets = 0; | |
2026 | int i; | |
b5b8b0ac | 2027 | struct cselib_set sets[MAX_SETS]; |
fa49fd0f | 2028 | rtx body = PATTERN (insn); |
b7933c21 | 2029 | rtx cond = 0; |
fa49fd0f RK |
2030 | |
2031 | body = PATTERN (insn); | |
b7933c21 BS |
2032 | if (GET_CODE (body) == COND_EXEC) |
2033 | { | |
2034 | cond = COND_EXEC_TEST (body); | |
2035 | body = COND_EXEC_CODE (body); | |
2036 | } | |
2037 | ||
fa49fd0f RK |
2038 | /* Find all sets. */ |
2039 | if (GET_CODE (body) == SET) | |
2040 | { | |
2041 | sets[0].src = SET_SRC (body); | |
2042 | sets[0].dest = SET_DEST (body); | |
2043 | n_sets = 1; | |
2044 | } | |
2045 | else if (GET_CODE (body) == PARALLEL) | |
2046 | { | |
2047 | /* Look through the PARALLEL and record the values being | |
2048 | set, if possible. Also handle any CLOBBERs. */ | |
2049 | for (i = XVECLEN (body, 0) - 1; i >= 0; --i) | |
2050 | { | |
2051 | rtx x = XVECEXP (body, 0, i); | |
2052 | ||
2053 | if (GET_CODE (x) == SET) | |
2054 | { | |
2055 | sets[n_sets].src = SET_SRC (x); | |
2056 | sets[n_sets].dest = SET_DEST (x); | |
2057 | n_sets++; | |
2058 | } | |
2059 | } | |
2060 | } | |
2061 | ||
8dd5516b JJ |
2062 | if (n_sets == 1 |
2063 | && MEM_P (sets[0].src) | |
2064 | && !cselib_record_memory | |
2065 | && MEM_READONLY_P (sets[0].src)) | |
2066 | { | |
2067 | rtx note = find_reg_equal_equiv_note (insn); | |
2068 | ||
2069 | if (note && CONSTANT_P (XEXP (note, 0))) | |
2070 | sets[0].src = XEXP (note, 0); | |
2071 | } | |
2072 | ||
fa49fd0f RK |
2073 | /* Look up the values that are read. Do this before invalidating the |
2074 | locations that are written. */ | |
2075 | for (i = 0; i < n_sets; i++) | |
2076 | { | |
2077 | rtx dest = sets[i].dest; | |
2078 | ||
2079 | /* A STRICT_LOW_PART can be ignored; we'll record the equivalence for | |
2080 | the low part after invalidating any knowledge about larger modes. */ | |
2081 | if (GET_CODE (sets[i].dest) == STRICT_LOW_PART) | |
2082 | sets[i].dest = dest = XEXP (dest, 0); | |
2083 | ||
2084 | /* We don't know how to record anything but REG or MEM. */ | |
f8cfc6aa | 2085 | if (REG_P (dest) |
3c0cb5de | 2086 | || (MEM_P (dest) && cselib_record_memory)) |
fa49fd0f | 2087 | { |
b7933c21 BS |
2088 | rtx src = sets[i].src; |
2089 | if (cond) | |
be9ed5d5 | 2090 | src = gen_rtx_IF_THEN_ELSE (GET_MODE (dest), cond, src, dest); |
37060e78 | 2091 | sets[i].src_elt = cselib_lookup (src, GET_MODE (dest), 1); |
3c0cb5de | 2092 | if (MEM_P (dest)) |
d4ebfa65 BE |
2093 | { |
2094 | enum machine_mode address_mode | |
2095 | = targetm.addr_space.address_mode (MEM_ADDR_SPACE (dest)); | |
2096 | ||
2097 | sets[i].dest_addr_elt = cselib_lookup (XEXP (dest, 0), | |
2098 | address_mode, 1); | |
2099 | } | |
fa49fd0f RK |
2100 | else |
2101 | sets[i].dest_addr_elt = 0; | |
2102 | } | |
2103 | } | |
2104 | ||
b5b8b0ac AO |
2105 | if (cselib_record_sets_hook) |
2106 | cselib_record_sets_hook (insn, sets, n_sets); | |
2107 | ||
fa49fd0f RK |
2108 | /* Invalidate all locations written by this insn. Note that the elts we |
2109 | looked up in the previous loop aren't affected, just some of their | |
2110 | locations may go away. */ | |
0d87c765 | 2111 | note_stores (body, cselib_invalidate_rtx_note_stores, NULL); |
fa49fd0f | 2112 | |
b7048ab7 RH |
2113 | /* If this is an asm, look for duplicate sets. This can happen when the |
2114 | user uses the same value as an output multiple times. This is valid | |
2115 | if the outputs are not actually used thereafter. Treat this case as | |
2116 | if the value isn't actually set. We do this by smashing the destination | |
2117 | to pc_rtx, so that we won't record the value later. */ | |
2118 | if (n_sets >= 2 && asm_noperands (body) >= 0) | |
2119 | { | |
2120 | for (i = 0; i < n_sets; i++) | |
2121 | { | |
2122 | rtx dest = sets[i].dest; | |
3c0cb5de | 2123 | if (REG_P (dest) || MEM_P (dest)) |
b7048ab7 RH |
2124 | { |
2125 | int j; | |
2126 | for (j = i + 1; j < n_sets; j++) | |
2127 | if (rtx_equal_p (dest, sets[j].dest)) | |
2128 | { | |
2129 | sets[i].dest = pc_rtx; | |
2130 | sets[j].dest = pc_rtx; | |
2131 | } | |
2132 | } | |
2133 | } | |
2134 | } | |
2135 | ||
fa49fd0f RK |
2136 | /* Now enter the equivalences in our tables. */ |
2137 | for (i = 0; i < n_sets; i++) | |
2138 | { | |
2139 | rtx dest = sets[i].dest; | |
f8cfc6aa | 2140 | if (REG_P (dest) |
3c0cb5de | 2141 | || (MEM_P (dest) && cselib_record_memory)) |
fa49fd0f RK |
2142 | cselib_record_set (dest, sets[i].src_elt, sets[i].dest_addr_elt); |
2143 | } | |
2144 | } | |
2145 | ||
2146 | /* Record the effects of INSN. */ | |
2147 | ||
2148 | void | |
7080f735 | 2149 | cselib_process_insn (rtx insn) |
fa49fd0f RK |
2150 | { |
2151 | int i; | |
2152 | rtx x; | |
2153 | ||
2154 | cselib_current_insn = insn; | |
2155 | ||
2156 | /* Forget everything at a CODE_LABEL, a volatile asm, or a setjmp. */ | |
4b4bf941 JQ |
2157 | if (LABEL_P (insn) |
2158 | || (CALL_P (insn) | |
570a98eb | 2159 | && find_reg_note (insn, REG_SETJMP, NULL)) |
4b4bf941 | 2160 | || (NONJUMP_INSN_P (insn) |
fa49fd0f RK |
2161 | && GET_CODE (PATTERN (insn)) == ASM_OPERANDS |
2162 | && MEM_VOLATILE_P (PATTERN (insn)))) | |
2163 | { | |
5440c0e7 | 2164 | cselib_reset_table (next_uid); |
2080bd29 | 2165 | cselib_current_insn = NULL_RTX; |
fa49fd0f RK |
2166 | return; |
2167 | } | |
2168 | ||
2169 | if (! INSN_P (insn)) | |
2170 | { | |
2080bd29 | 2171 | cselib_current_insn = NULL_RTX; |
fa49fd0f RK |
2172 | return; |
2173 | } | |
2174 | ||
2175 | /* If this is a call instruction, forget anything stored in a | |
2176 | call clobbered register, or, if this is not a const call, in | |
2177 | memory. */ | |
4b4bf941 | 2178 | if (CALL_P (insn)) |
fa49fd0f RK |
2179 | { |
2180 | for (i = 0; i < FIRST_PSEUDO_REGISTER; i++) | |
7e42db17 DJ |
2181 | if (call_used_regs[i] |
2182 | || (REG_VALUES (i) && REG_VALUES (i)->elt | |
b8698a0f | 2183 | && HARD_REGNO_CALL_PART_CLOBBERED (i, |
757bbef8 | 2184 | GET_MODE (REG_VALUES (i)->elt->val_rtx)))) |
291aac59 | 2185 | cselib_invalidate_regno (i, reg_raw_mode[i]); |
fa49fd0f | 2186 | |
becfd6e5 KZ |
2187 | /* Since it is not clear how cselib is going to be used, be |
2188 | conservative here and treat looping pure or const functions | |
2189 | as if they were regular functions. */ | |
2190 | if (RTL_LOOPING_CONST_OR_PURE_CALL_P (insn) | |
2191 | || !(RTL_CONST_OR_PURE_CALL_P (insn))) | |
fa49fd0f RK |
2192 | cselib_invalidate_mem (callmem); |
2193 | } | |
2194 | ||
2195 | cselib_record_sets (insn); | |
2196 | ||
2197 | #ifdef AUTO_INC_DEC | |
2198 | /* Clobber any registers which appear in REG_INC notes. We | |
2199 | could keep track of the changes to their values, but it is | |
2200 | unlikely to help. */ | |
2201 | for (x = REG_NOTES (insn); x; x = XEXP (x, 1)) | |
2202 | if (REG_NOTE_KIND (x) == REG_INC) | |
0d87c765 | 2203 | cselib_invalidate_rtx (XEXP (x, 0)); |
fa49fd0f RK |
2204 | #endif |
2205 | ||
2206 | /* Look for any CLOBBERs in CALL_INSN_FUNCTION_USAGE, but only | |
2207 | after we have processed the insn. */ | |
4b4bf941 | 2208 | if (CALL_P (insn)) |
fa49fd0f RK |
2209 | for (x = CALL_INSN_FUNCTION_USAGE (insn); x; x = XEXP (x, 1)) |
2210 | if (GET_CODE (XEXP (x, 0)) == CLOBBER) | |
0d87c765 | 2211 | cselib_invalidate_rtx (XEXP (XEXP (x, 0), 0)); |
fa49fd0f | 2212 | |
2080bd29 | 2213 | cselib_current_insn = NULL_RTX; |
fa49fd0f | 2214 | |
96d0cc81 JH |
2215 | if (n_useless_values > MAX_USELESS_VALUES |
2216 | /* remove_useless_values is linear in the hash table size. Avoid | |
9f5ed61a | 2217 | quadratic behavior for very large hashtables with very few |
96d0cc81 | 2218 | useless elements. */ |
5847e8da AO |
2219 | && ((unsigned int)n_useless_values |
2220 | > (cselib_hash_table->n_elements | |
2221 | - cselib_hash_table->n_deleted | |
2222 | - n_debug_values) / 4)) | |
fa49fd0f RK |
2223 | remove_useless_values (); |
2224 | } | |
2225 | ||
fa49fd0f RK |
2226 | /* Initialize cselib for one pass. The caller must also call |
2227 | init_alias_analysis. */ | |
2228 | ||
2229 | void | |
457eeaae | 2230 | cselib_init (int record_what) |
fa49fd0f | 2231 | { |
b8698a0f | 2232 | elt_list_pool = create_alloc_pool ("elt_list", |
6a59927d | 2233 | sizeof (struct elt_list), 10); |
b8698a0f | 2234 | elt_loc_list_pool = create_alloc_pool ("elt_loc_list", |
6a59927d | 2235 | sizeof (struct elt_loc_list), 10); |
b8698a0f | 2236 | cselib_val_pool = create_alloc_pool ("cselib_val_list", |
6a59927d | 2237 | sizeof (cselib_val), 10); |
aacd3885 | 2238 | value_pool = create_alloc_pool ("value", RTX_CODE_SIZE (VALUE), 100); |
457eeaae JJ |
2239 | cselib_record_memory = record_what & CSELIB_RECORD_MEMORY; |
2240 | cselib_preserve_constants = record_what & CSELIB_PRESERVE_CONSTANTS; | |
ac3768f6 SB |
2241 | |
2242 | /* (mem:BLK (scratch)) is a special mechanism to conflict with everything, | |
2243 | see canon_true_dependence. This is only created once. */ | |
fa49fd0f | 2244 | if (! callmem) |
ac3768f6 | 2245 | callmem = gen_rtx_MEM (BLKmode, gen_rtx_SCRATCH (VOIDmode)); |
fa49fd0f RK |
2246 | |
2247 | cselib_nregs = max_reg_num (); | |
6790d1ab JH |
2248 | |
2249 | /* We preserve reg_values to allow expensive clearing of the whole thing. | |
2250 | Reallocate it however if it happens to be too large. */ | |
2251 | if (!reg_values || reg_values_size < cselib_nregs | |
2252 | || (reg_values_size > 10 && reg_values_size > cselib_nregs * 4)) | |
e2500fed | 2253 | { |
6790d1ab JH |
2254 | if (reg_values) |
2255 | free (reg_values); | |
2256 | /* Some space for newly emit instructions so we don't end up | |
2257 | reallocating in between passes. */ | |
2258 | reg_values_size = cselib_nregs + (63 + cselib_nregs) / 16; | |
5ed6ace5 | 2259 | reg_values = XCNEWVEC (struct elt_list *, reg_values_size); |
e2500fed | 2260 | } |
5ed6ace5 | 2261 | used_regs = XNEWVEC (unsigned int, cselib_nregs); |
6790d1ab | 2262 | n_used_regs = 0; |
7c514720 KH |
2263 | cselib_hash_table = htab_create (31, get_value_hash, |
2264 | entry_and_rtx_equal_p, NULL); | |
5440c0e7 | 2265 | next_uid = 1; |
fa49fd0f RK |
2266 | } |
2267 | ||
2268 | /* Called when the current user is done with cselib. */ | |
2269 | ||
2270 | void | |
7080f735 | 2271 | cselib_finish (void) |
fa49fd0f | 2272 | { |
6fb5fa3c | 2273 | cselib_discard_hook = NULL; |
457eeaae JJ |
2274 | cselib_preserve_constants = false; |
2275 | cfa_base_preserved_val = NULL; | |
9de9cbaf | 2276 | cfa_base_preserved_regno = INVALID_REGNUM; |
6a59927d JH |
2277 | free_alloc_pool (elt_list_pool); |
2278 | free_alloc_pool (elt_loc_list_pool); | |
2279 | free_alloc_pool (cselib_val_pool); | |
23bd7a93 | 2280 | free_alloc_pool (value_pool); |
eb232f4e | 2281 | cselib_clear_table (); |
7c514720 | 2282 | htab_delete (cselib_hash_table); |
0fc0c4c9 | 2283 | free (used_regs); |
e2500fed | 2284 | used_regs = 0; |
7c514720 | 2285 | cselib_hash_table = 0; |
e2500fed | 2286 | n_useless_values = 0; |
5847e8da AO |
2287 | n_useless_debug_values = 0; |
2288 | n_debug_values = 0; | |
5440c0e7 | 2289 | next_uid = 0; |
fa49fd0f | 2290 | } |
e2500fed | 2291 | |
b5b8b0ac AO |
2292 | /* Dump the cselib_val *X to FILE *info. */ |
2293 | ||
2294 | static int | |
2295 | dump_cselib_val (void **x, void *info) | |
2296 | { | |
2297 | cselib_val *v = (cselib_val *)*x; | |
2298 | FILE *out = (FILE *)info; | |
2299 | bool need_lf = true; | |
2300 | ||
2301 | print_inline_rtx (out, v->val_rtx, 0); | |
2302 | ||
2303 | if (v->locs) | |
2304 | { | |
2305 | struct elt_loc_list *l = v->locs; | |
2306 | if (need_lf) | |
2307 | { | |
2308 | fputc ('\n', out); | |
2309 | need_lf = false; | |
2310 | } | |
2311 | fputs (" locs:", out); | |
2312 | do | |
2313 | { | |
2314 | fprintf (out, "\n from insn %i ", | |
2315 | INSN_UID (l->setting_insn)); | |
2316 | print_inline_rtx (out, l->loc, 4); | |
2317 | } | |
2318 | while ((l = l->next)); | |
2319 | fputc ('\n', out); | |
2320 | } | |
2321 | else | |
2322 | { | |
2323 | fputs (" no locs", out); | |
2324 | need_lf = true; | |
2325 | } | |
2326 | ||
2327 | if (v->addr_list) | |
2328 | { | |
2329 | struct elt_list *e = v->addr_list; | |
2330 | if (need_lf) | |
2331 | { | |
2332 | fputc ('\n', out); | |
2333 | need_lf = false; | |
2334 | } | |
2335 | fputs (" addr list:", out); | |
2336 | do | |
2337 | { | |
2338 | fputs ("\n ", out); | |
2339 | print_inline_rtx (out, e->elt->val_rtx, 2); | |
2340 | } | |
2341 | while ((e = e->next)); | |
2342 | fputc ('\n', out); | |
2343 | } | |
2344 | else | |
2345 | { | |
2346 | fputs (" no addrs", out); | |
2347 | need_lf = true; | |
2348 | } | |
2349 | ||
2350 | if (v->next_containing_mem == &dummy_val) | |
2351 | fputs (" last mem\n", out); | |
2352 | else if (v->next_containing_mem) | |
2353 | { | |
2354 | fputs (" next mem ", out); | |
2355 | print_inline_rtx (out, v->next_containing_mem->val_rtx, 2); | |
2356 | fputc ('\n', out); | |
2357 | } | |
2358 | else if (need_lf) | |
2359 | fputc ('\n', out); | |
2360 | ||
2361 | return 1; | |
2362 | } | |
2363 | ||
2364 | /* Dump to OUT everything in the CSELIB table. */ | |
2365 | ||
2366 | void | |
2367 | dump_cselib_table (FILE *out) | |
2368 | { | |
2369 | fprintf (out, "cselib hash table:\n"); | |
2370 | htab_traverse (cselib_hash_table, dump_cselib_val, out); | |
2371 | if (first_containing_mem != &dummy_val) | |
2372 | { | |
2373 | fputs ("first mem ", out); | |
2374 | print_inline_rtx (out, first_containing_mem->val_rtx, 2); | |
2375 | fputc ('\n', out); | |
2376 | } | |
5440c0e7 | 2377 | fprintf (out, "next uid %i\n", next_uid); |
b5b8b0ac AO |
2378 | } |
2379 | ||
e2500fed | 2380 | #include "gt-cselib.h" |