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6fb5fa3c | 1 | /* RTL dead store elimination. |
cbe34bb5 | 2 | Copyright (C) 2005-2017 Free Software Foundation, Inc. |
6fb5fa3c DB |
3 | |
4 | Contributed by Richard Sandiford <rsandifor@codesourcery.com> | |
5 | and Kenneth Zadeck <zadeck@naturalbridge.com> | |
6 | ||
7 | This file is part of GCC. | |
8 | ||
9 | GCC is free software; you can redistribute it and/or modify it under | |
10 | the terms of the GNU General Public License as published by the Free | |
9dcd6f09 | 11 | Software Foundation; either version 3, or (at your option) any later |
6fb5fa3c DB |
12 | version. |
13 | ||
14 | GCC is distributed in the hope that it will be useful, but WITHOUT ANY | |
15 | WARRANTY; without even the implied warranty of MERCHANTABILITY or | |
16 | FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License | |
17 | for more details. | |
18 | ||
19 | You should have received a copy of the GNU General Public License | |
9dcd6f09 NC |
20 | along with GCC; see the file COPYING3. If not see |
21 | <http://www.gnu.org/licenses/>. */ | |
6fb5fa3c DB |
22 | |
23 | #undef BASELINE | |
24 | ||
25 | #include "config.h" | |
26 | #include "system.h" | |
27 | #include "coretypes.h" | |
c7131fb2 | 28 | #include "backend.h" |
957060b5 AM |
29 | #include "target.h" |
30 | #include "rtl.h" | |
c7131fb2 AM |
31 | #include "tree.h" |
32 | #include "gimple.h" | |
957060b5 | 33 | #include "predict.h" |
c7131fb2 | 34 | #include "df.h" |
4d0cdd0c | 35 | #include "memmodel.h" |
957060b5 AM |
36 | #include "tm_p.h" |
37 | #include "gimple-ssa.h" | |
38 | #include "expmed.h" | |
39 | #include "optabs.h" | |
957060b5 AM |
40 | #include "emit-rtl.h" |
41 | #include "recog.h" | |
40e23961 | 42 | #include "alias.h" |
d8a2d370 | 43 | #include "stor-layout.h" |
60393bbc | 44 | #include "cfgrtl.h" |
6fb5fa3c | 45 | #include "cselib.h" |
6fb5fa3c | 46 | #include "tree-pass.h" |
36566b39 | 47 | #include "explow.h" |
6fb5fa3c | 48 | #include "expr.h" |
6fb5fa3c | 49 | #include "dbgcnt.h" |
dabd47e7 | 50 | #include "params.h" |
d7111da8 | 51 | #include "rtl-iter.h" |
6c5ed3f1 | 52 | #include "cfgcleanup.h" |
6fb5fa3c DB |
53 | |
54 | /* This file contains three techniques for performing Dead Store | |
b8698a0f | 55 | Elimination (dse). |
6fb5fa3c DB |
56 | |
57 | * The first technique performs dse locally on any base address. It | |
58 | is based on the cselib which is a local value numbering technique. | |
59 | This technique is local to a basic block but deals with a fairly | |
60 | general addresses. | |
b8698a0f | 61 | |
6fb5fa3c DB |
62 | * The second technique performs dse globally but is restricted to |
63 | base addresses that are either constant or are relative to the | |
64 | frame_pointer. | |
65 | ||
66 | * The third technique, (which is only done after register allocation) | |
026c3cfd | 67 | processes the spill slots. This differs from the second |
6fb5fa3c DB |
68 | technique because it takes advantage of the fact that spilling is |
69 | completely free from the effects of aliasing. | |
70 | ||
71 | Logically, dse is a backwards dataflow problem. A store can be | |
72 | deleted if it if cannot be reached in the backward direction by any | |
73 | use of the value being stored. However, the local technique uses a | |
74 | forwards scan of the basic block because cselib requires that the | |
75 | block be processed in that order. | |
76 | ||
77 | The pass is logically broken into 7 steps: | |
78 | ||
79 | 0) Initialization. | |
80 | ||
81 | 1) The local algorithm, as well as scanning the insns for the two | |
82 | global algorithms. | |
83 | ||
84 | 2) Analysis to see if the global algs are necessary. In the case | |
85 | of stores base on a constant address, there must be at least two | |
86 | stores to that address, to make it possible to delete some of the | |
87 | stores. In the case of stores off of the frame or spill related | |
88 | stores, only one store to an address is necessary because those | |
89 | stores die at the end of the function. | |
90 | ||
b8698a0f | 91 | 3) Set up the global dataflow equations based on processing the |
6fb5fa3c DB |
92 | info parsed in the first step. |
93 | ||
94 | 4) Solve the dataflow equations. | |
95 | ||
96 | 5) Delete the insns that the global analysis has indicated are | |
97 | unnecessary. | |
98 | ||
073a8998 | 99 | 6) Delete insns that store the same value as preceding store |
8dd5516b JJ |
100 | where the earlier store couldn't be eliminated. |
101 | ||
102 | 7) Cleanup. | |
6fb5fa3c DB |
103 | |
104 | This step uses cselib and canon_rtx to build the largest expression | |
105 | possible for each address. This pass is a forwards pass through | |
106 | each basic block. From the point of view of the global technique, | |
107 | the first pass could examine a block in either direction. The | |
0d52bcc1 | 108 | forwards ordering is to accommodate cselib. |
6fb5fa3c | 109 | |
5ef0b50d | 110 | We make a simplifying assumption: addresses fall into four broad |
6fb5fa3c DB |
111 | categories: |
112 | ||
113 | 1) base has rtx_varies_p == false, offset is constant. | |
114 | 2) base has rtx_varies_p == false, offset variable. | |
115 | 3) base has rtx_varies_p == true, offset constant. | |
116 | 4) base has rtx_varies_p == true, offset variable. | |
117 | ||
118 | The local passes are able to process all 4 kinds of addresses. The | |
5ef0b50d | 119 | global pass only handles 1). |
6fb5fa3c DB |
120 | |
121 | The global problem is formulated as follows: | |
122 | ||
123 | A store, S1, to address A, where A is not relative to the stack | |
124 | frame, can be eliminated if all paths from S1 to the end of the | |
5ef0b50d | 125 | function contain another store to A before a read to A. |
6fb5fa3c DB |
126 | |
127 | If the address A is relative to the stack frame, a store S2 to A | |
5ef0b50d | 128 | can be eliminated if there are no paths from S2 that reach the |
6fb5fa3c | 129 | end of the function that read A before another store to A. In |
5ef0b50d | 130 | this case S2 can be deleted if there are paths from S2 to the |
6fb5fa3c DB |
131 | end of the function that have no reads or writes to A. This |
132 | second case allows stores to the stack frame to be deleted that | |
133 | would otherwise die when the function returns. This cannot be | |
134 | done if stores_off_frame_dead_at_return is not true. See the doc | |
135 | for that variable for when this variable is false. | |
136 | ||
137 | The global problem is formulated as a backwards set union | |
138 | dataflow problem where the stores are the gens and reads are the | |
139 | kills. Set union problems are rare and require some special | |
140 | handling given our representation of bitmaps. A straightforward | |
5ef0b50d | 141 | implementation requires a lot of bitmaps filled with 1s. |
6fb5fa3c DB |
142 | These are expensive and cumbersome in our bitmap formulation so |
143 | care has been taken to avoid large vectors filled with 1s. See | |
144 | the comments in bb_info and in the dataflow confluence functions | |
b8698a0f | 145 | for details. |
6fb5fa3c DB |
146 | |
147 | There are two places for further enhancements to this algorithm: | |
b8698a0f | 148 | |
6fb5fa3c DB |
149 | 1) The original dse which was embedded in a pass called flow also |
150 | did local address forwarding. For example in | |
151 | ||
152 | A <- r100 | |
153 | ... <- A | |
154 | ||
155 | flow would replace the right hand side of the second insn with a | |
6ed3da00 | 156 | reference to r100. Most of the information is available to add this |
6fb5fa3c DB |
157 | to this pass. It has not done it because it is a lot of work in |
158 | the case that either r100 is assigned to between the first and | |
159 | second insn and/or the second insn is a load of part of the value | |
160 | stored by the first insn. | |
161 | ||
162 | insn 5 in gcc.c-torture/compile/990203-1.c simple case. | |
163 | insn 15 in gcc.c-torture/execute/20001017-2.c simple case. | |
164 | insn 25 in gcc.c-torture/execute/20001026-1.c simple case. | |
165 | insn 44 in gcc.c-torture/execute/20010910-1.c simple case. | |
166 | ||
167 | 2) The cleaning up of spill code is quite profitable. It currently | |
168 | depends on reading tea leaves and chicken entrails left by reload. | |
169 | This pass depends on reload creating a singleton alias set for each | |
170 | spill slot and telling the next dse pass which of these alias sets | |
171 | are the singletons. Rather than analyze the addresses of the | |
172 | spills, dse's spill processing just does analysis of the loads and | |
173 | stores that use those alias sets. There are three cases where this | |
174 | falls short: | |
175 | ||
176 | a) Reload sometimes creates the slot for one mode of access, and | |
177 | then inserts loads and/or stores for a smaller mode. In this | |
178 | case, the current code just punts on the slot. The proper thing | |
179 | to do is to back out and use one bit vector position for each | |
180 | byte of the entity associated with the slot. This depends on | |
181 | KNOWING that reload always generates the accesses for each of the | |
182 | bytes in some canonical (read that easy to understand several | |
183 | passes after reload happens) way. | |
184 | ||
185 | b) Reload sometimes decides that spill slot it allocated was not | |
186 | large enough for the mode and goes back and allocates more slots | |
187 | with the same mode and alias set. The backout in this case is a | |
188 | little more graceful than (a). In this case the slot is unmarked | |
189 | as being a spill slot and if final address comes out to be based | |
b8698a0f | 190 | off the frame pointer, the global algorithm handles this slot. |
6fb5fa3c DB |
191 | |
192 | c) For any pass that may prespill, there is currently no | |
193 | mechanism to tell the dse pass that the slot being used has the | |
194 | special properties that reload uses. It may be that all that is | |
0d52bcc1 | 195 | required is to have those passes make the same calls that reload |
6fb5fa3c DB |
196 | does, assuming that the alias sets can be manipulated in the same |
197 | way. */ | |
198 | ||
199 | /* There are limits to the size of constant offsets we model for the | |
200 | global problem. There are certainly test cases, that exceed this | |
201 | limit, however, it is unlikely that there are important programs | |
202 | that really have constant offsets this size. */ | |
203 | #define MAX_OFFSET (64 * 1024) | |
204 | ||
3f9b14ff SB |
205 | /* Obstack for the DSE dataflow bitmaps. We don't want to put these |
206 | on the default obstack because these bitmaps can grow quite large | |
207 | (~2GB for the small (!) test case of PR54146) and we'll hold on to | |
208 | all that memory until the end of the compiler run. | |
209 | As a bonus, delete_tree_live_info can destroy all the bitmaps by just | |
210 | releasing the whole obstack. */ | |
211 | static bitmap_obstack dse_bitmap_obstack; | |
212 | ||
213 | /* Obstack for other data. As for above: Kinda nice to be able to | |
214 | throw it all away at the end in one big sweep. */ | |
215 | static struct obstack dse_obstack; | |
216 | ||
217 | /* Scratch bitmap for cselib's cselib_expand_value_rtx. */ | |
6fb5fa3c | 218 | static bitmap scratch = NULL; |
3f9b14ff | 219 | |
da6603c6 | 220 | struct insn_info_type; |
6fb5fa3c DB |
221 | |
222 | /* This structure holds information about a candidate store. */ | |
b8698a0f | 223 | struct store_info |
6fb5fa3c DB |
224 | { |
225 | ||
226 | /* False means this is a clobber. */ | |
227 | bool is_set; | |
228 | ||
8dd5516b JJ |
229 | /* False if a single HOST_WIDE_INT bitmap is used for positions_needed. */ |
230 | bool is_large; | |
231 | ||
6fb5fa3c DB |
232 | /* The id of the mem group of the base address. If rtx_varies_p is |
233 | true, this is -1. Otherwise, it is the index into the group | |
234 | table. */ | |
235 | int group_id; | |
b8698a0f | 236 | |
6fb5fa3c DB |
237 | /* This is the cselib value. */ |
238 | cselib_val *cse_base; | |
239 | ||
240 | /* This canonized mem. */ | |
241 | rtx mem; | |
242 | ||
6216f94e | 243 | /* Canonized MEM address for use by canon_true_dependence. */ |
6fb5fa3c DB |
244 | rtx mem_addr; |
245 | ||
6fb5fa3c DB |
246 | /* The offset of the first and byte before the last byte associated |
247 | with the operation. */ | |
8dd5516b JJ |
248 | HOST_WIDE_INT begin, end; |
249 | ||
250 | union | |
251 | { | |
252 | /* A bitmask as wide as the number of bytes in the word that | |
253 | contains a 1 if the byte may be needed. The store is unused if | |
254 | all of the bits are 0. This is used if IS_LARGE is false. */ | |
255 | unsigned HOST_WIDE_INT small_bitmask; | |
256 | ||
257 | struct | |
258 | { | |
259 | /* A bitmap with one bit per byte. Cleared bit means the position | |
260 | is needed. Used if IS_LARGE is false. */ | |
dc491a25 | 261 | bitmap bmap; |
6fb5fa3c | 262 | |
8dd5516b JJ |
263 | /* Number of set bits (i.e. unneeded bytes) in BITMAP. If it is |
264 | equal to END - BEGIN, the whole store is unused. */ | |
265 | int count; | |
266 | } large; | |
267 | } positions_needed; | |
6fb5fa3c DB |
268 | |
269 | /* The next store info for this insn. */ | |
270 | struct store_info *next; | |
271 | ||
272 | /* The right hand side of the store. This is used if there is a | |
273 | subsequent reload of the mems address somewhere later in the | |
274 | basic block. */ | |
8dd5516b JJ |
275 | rtx rhs; |
276 | ||
277 | /* If rhs is or holds a constant, this contains that constant, | |
278 | otherwise NULL. */ | |
279 | rtx const_rhs; | |
280 | ||
281 | /* Set if this store stores the same constant value as REDUNDANT_REASON | |
282 | insn stored. These aren't eliminated early, because doing that | |
283 | might prevent the earlier larger store to be eliminated. */ | |
da6603c6 | 284 | struct insn_info_type *redundant_reason; |
6fb5fa3c DB |
285 | }; |
286 | ||
4fe663b0 L |
287 | /* Return a bitmask with the first N low bits set. */ |
288 | ||
289 | static unsigned HOST_WIDE_INT | |
290 | lowpart_bitmask (int n) | |
291 | { | |
dd4786fe | 292 | unsigned HOST_WIDE_INT mask = HOST_WIDE_INT_M1U; |
4fe663b0 L |
293 | return mask >> (HOST_BITS_PER_WIDE_INT - n); |
294 | } | |
295 | ||
fcb87c50 | 296 | static object_allocator<store_info> cse_store_info_pool ("cse_store_info_pool"); |
da6603c6 | 297 | |
fcb87c50 | 298 | static object_allocator<store_info> rtx_store_info_pool ("rtx_store_info_pool"); |
6fb5fa3c DB |
299 | |
300 | /* This structure holds information about a load. These are only | |
301 | built for rtx bases. */ | |
da6603c6 | 302 | struct read_info_type |
6fb5fa3c DB |
303 | { |
304 | /* The id of the mem group of the base address. */ | |
305 | int group_id; | |
306 | ||
6fb5fa3c DB |
307 | /* The offset of the first and byte after the last byte associated |
308 | with the operation. If begin == end == 0, the read did not have | |
309 | a constant offset. */ | |
310 | int begin, end; | |
311 | ||
312 | /* The mem being read. */ | |
313 | rtx mem; | |
314 | ||
315 | /* The next read_info for this insn. */ | |
da6603c6 | 316 | struct read_info_type *next; |
6fb5fa3c | 317 | }; |
da6603c6 | 318 | typedef struct read_info_type *read_info_t; |
6fb5fa3c | 319 | |
fcb87c50 | 320 | static object_allocator<read_info_type> read_info_type_pool ("read_info_pool"); |
6fb5fa3c DB |
321 | |
322 | /* One of these records is created for each insn. */ | |
323 | ||
da6603c6 | 324 | struct insn_info_type |
6fb5fa3c DB |
325 | { |
326 | /* Set true if the insn contains a store but the insn itself cannot | |
327 | be deleted. This is set if the insn is a parallel and there is | |
328 | more than one non dead output or if the insn is in some way | |
329 | volatile. */ | |
330 | bool cannot_delete; | |
331 | ||
332 | /* This field is only used by the global algorithm. It is set true | |
333 | if the insn contains any read of mem except for a (1). This is | |
334 | also set if the insn is a call or has a clobber mem. If the insn | |
335 | contains a wild read, the use_rec will be null. */ | |
336 | bool wild_read; | |
337 | ||
d26c7090 ER |
338 | /* This is true only for CALL instructions which could potentially read |
339 | any non-frame memory location. This field is used by the global | |
340 | algorithm. */ | |
341 | bool non_frame_wild_read; | |
342 | ||
50f0f366 EB |
343 | /* This field is only used for the processing of const functions. |
344 | These functions cannot read memory, but they can read the stack | |
64520bdc EB |
345 | because that is where they may get their parms. We need to be |
346 | this conservative because, like the store motion pass, we don't | |
347 | consider CALL_INSN_FUNCTION_USAGE when processing call insns. | |
348 | Moreover, we need to distinguish two cases: | |
349 | 1. Before reload (register elimination), the stores related to | |
350 | outgoing arguments are stack pointer based and thus deemed | |
351 | of non-constant base in this pass. This requires special | |
352 | handling but also means that the frame pointer based stores | |
353 | need not be killed upon encountering a const function call. | |
354 | 2. After reload, the stores related to outgoing arguments can be | |
355 | either stack pointer or hard frame pointer based. This means | |
356 | that we have no other choice than also killing all the frame | |
357 | pointer based stores upon encountering a const function call. | |
57534689 JJ |
358 | This field is set after reload for const function calls and before |
359 | reload for const tail function calls on targets where arg pointer | |
360 | is the frame pointer. Having this set is less severe than a wild | |
361 | read, it just means that all the frame related stores are killed | |
362 | rather than all the stores. */ | |
64520bdc EB |
363 | bool frame_read; |
364 | ||
365 | /* This field is only used for the processing of const functions. | |
366 | It is set if the insn may contain a stack pointer based store. */ | |
50f0f366 | 367 | bool stack_pointer_based; |
6fb5fa3c DB |
368 | |
369 | /* This is true if any of the sets within the store contains a | |
370 | cselib base. Such stores can only be deleted by the local | |
371 | algorithm. */ | |
372 | bool contains_cselib_groups; | |
373 | ||
374 | /* The insn. */ | |
dd60a84c | 375 | rtx_insn *insn; |
6fb5fa3c DB |
376 | |
377 | /* The list of mem sets or mem clobbers that are contained in this | |
378 | insn. If the insn is deletable, it contains only one mem set. | |
379 | But it could also contain clobbers. Insns that contain more than | |
380 | one mem set are not deletable, but each of those mems are here in | |
6ed3da00 | 381 | order to provide info to delete other insns. */ |
fd6daec9 | 382 | store_info *store_rec; |
6fb5fa3c DB |
383 | |
384 | /* The linked list of mem uses in this insn. Only the reads from | |
385 | rtx bases are listed here. The reads to cselib bases are | |
386 | completely processed during the first scan and so are never | |
387 | created. */ | |
388 | read_info_t read_rec; | |
389 | ||
9e582b1d JR |
390 | /* The live fixed registers. We assume only fixed registers can |
391 | cause trouble by being clobbered from an expanded pattern; | |
392 | storing only the live fixed registers (rather than all registers) | |
393 | means less memory needs to be allocated / copied for the individual | |
394 | stores. */ | |
395 | regset fixed_regs_live; | |
396 | ||
6fb5fa3c | 397 | /* The prev insn in the basic block. */ |
da6603c6 | 398 | struct insn_info_type * prev_insn; |
6fb5fa3c DB |
399 | |
400 | /* The linked list of insns that are in consideration for removal in | |
073a8998 | 401 | the forwards pass through the basic block. This pointer may be |
6fb5fa3c | 402 | trash as it is not cleared when a wild read occurs. The only |
fa10beec | 403 | time it is guaranteed to be correct is when the traversal starts |
6fb5fa3c | 404 | at active_local_stores. */ |
da6603c6 | 405 | struct insn_info_type * next_local_store; |
6fb5fa3c | 406 | }; |
da6603c6 | 407 | typedef struct insn_info_type *insn_info_t; |
6fb5fa3c | 408 | |
fcb87c50 | 409 | static object_allocator<insn_info_type> insn_info_type_pool ("insn_info_pool"); |
6fb5fa3c DB |
410 | |
411 | /* The linked list of stores that are under consideration in this | |
b8698a0f | 412 | basic block. */ |
6fb5fa3c | 413 | static insn_info_t active_local_stores; |
dabd47e7 | 414 | static int active_local_stores_len; |
6fb5fa3c | 415 | |
da6603c6 | 416 | struct dse_bb_info_type |
6fb5fa3c | 417 | { |
6fb5fa3c DB |
418 | /* Pointer to the insn info for the last insn in the block. These |
419 | are linked so this is how all of the insns are reached. During | |
420 | scanning this is the current insn being scanned. */ | |
421 | insn_info_t last_insn; | |
422 | ||
423 | /* The info for the global dataflow problem. */ | |
424 | ||
425 | ||
426 | /* This is set if the transfer function should and in the wild_read | |
427 | bitmap before applying the kill and gen sets. That vector knocks | |
428 | out most of the bits in the bitmap and thus speeds up the | |
429 | operations. */ | |
430 | bool apply_wild_read; | |
431 | ||
02b47899 KZ |
432 | /* The following 4 bitvectors hold information about which positions |
433 | of which stores are live or dead. They are indexed by | |
434 | get_bitmap_index. */ | |
435 | ||
6fb5fa3c DB |
436 | /* The set of store positions that exist in this block before a wild read. */ |
437 | bitmap gen; | |
b8698a0f | 438 | |
6fb5fa3c DB |
439 | /* The set of load positions that exist in this block above the |
440 | same position of a store. */ | |
441 | bitmap kill; | |
442 | ||
443 | /* The set of stores that reach the top of the block without being | |
444 | killed by a read. | |
445 | ||
446 | Do not represent the in if it is all ones. Note that this is | |
447 | what the bitvector should logically be initialized to for a set | |
448 | intersection problem. However, like the kill set, this is too | |
449 | expensive. So initially, the in set will only be created for the | |
450 | exit block and any block that contains a wild read. */ | |
451 | bitmap in; | |
452 | ||
453 | /* The set of stores that reach the bottom of the block from it's | |
454 | successors. | |
455 | ||
456 | Do not represent the in if it is all ones. Note that this is | |
457 | what the bitvector should logically be initialized to for a set | |
458 | intersection problem. However, like the kill and in set, this is | |
459 | too expensive. So what is done is that the confluence operator | |
460 | just initializes the vector from one of the out sets of the | |
461 | successors of the block. */ | |
462 | bitmap out; | |
02b47899 KZ |
463 | |
464 | /* The following bitvector is indexed by the reg number. It | |
465 | contains the set of regs that are live at the current instruction | |
466 | being processed. While it contains info for all of the | |
9e582b1d JR |
467 | registers, only the hard registers are actually examined. It is used |
468 | to assure that shift and/or add sequences that are inserted do not | |
073a8998 | 469 | accidentally clobber live hard regs. */ |
02b47899 | 470 | bitmap regs_live; |
6fb5fa3c DB |
471 | }; |
472 | ||
da6603c6 | 473 | typedef struct dse_bb_info_type *bb_info_t; |
fb0b2914 ML |
474 | |
475 | static object_allocator<dse_bb_info_type> dse_bb_info_type_pool | |
fcb87c50 | 476 | ("bb_info_pool"); |
6fb5fa3c DB |
477 | |
478 | /* Table to hold all bb_infos. */ | |
479 | static bb_info_t *bb_table; | |
480 | ||
481 | /* There is a group_info for each rtx base that is used to reference | |
482 | memory. There are also not many of the rtx bases because they are | |
483 | very limited in scope. */ | |
484 | ||
b8698a0f | 485 | struct group_info |
6fb5fa3c DB |
486 | { |
487 | /* The actual base of the address. */ | |
488 | rtx rtx_base; | |
489 | ||
490 | /* The sequential id of the base. This allows us to have a | |
491 | canonical ordering of these that is not based on addresses. */ | |
492 | int id; | |
493 | ||
8f5929e1 JJ |
494 | /* True if there are any positions that are to be processed |
495 | globally. */ | |
496 | bool process_globally; | |
497 | ||
498 | /* True if the base of this group is either the frame_pointer or | |
499 | hard_frame_pointer. */ | |
500 | bool frame_related; | |
501 | ||
d32f725a OH |
502 | /* A mem wrapped around the base pointer for the group in order to do |
503 | read dependency. It must be given BLKmode in order to encompass all | |
504 | the possible offsets from the base. */ | |
6fb5fa3c | 505 | rtx base_mem; |
b8698a0f | 506 | |
6216f94e JJ |
507 | /* Canonized version of base_mem's address. */ |
508 | rtx canon_base_addr; | |
6fb5fa3c DB |
509 | |
510 | /* These two sets of two bitmaps are used to keep track of how many | |
6ed3da00 | 511 | stores are actually referencing that position from this base. We |
6fb5fa3c | 512 | only do this for rtx bases as this will be used to assign |
6ed3da00 | 513 | positions in the bitmaps for the global problem. Bit N is set in |
6fb5fa3c DB |
514 | store1 on the first store for offset N. Bit N is set in store2 |
515 | for the second store to offset N. This is all we need since we | |
516 | only care about offsets that have two or more stores for them. | |
517 | ||
518 | The "_n" suffix is for offsets less than 0 and the "_p" suffix is | |
519 | for 0 and greater offsets. | |
520 | ||
521 | There is one special case here, for stores into the stack frame, | |
522 | we will or store1 into store2 before deciding which stores look | |
523 | at globally. This is because stores to the stack frame that have | |
524 | no other reads before the end of the function can also be | |
525 | deleted. */ | |
526 | bitmap store1_n, store1_p, store2_n, store2_p; | |
527 | ||
d26c7090 ER |
528 | /* These bitmaps keep track of offsets in this group escape this function. |
529 | An offset escapes if it corresponds to a named variable whose | |
530 | addressable flag is set. */ | |
531 | bitmap escaped_n, escaped_p; | |
532 | ||
6ed3da00 | 533 | /* The positions in this bitmap have the same assignments as the in, |
6fb5fa3c | 534 | out, gen and kill bitmaps. This bitmap is all zeros except for |
6ed3da00 | 535 | the positions that are occupied by stores for this group. */ |
6fb5fa3c DB |
536 | bitmap group_kill; |
537 | ||
6fb5fa3c | 538 | /* The offset_map is used to map the offsets from this base into |
6ed3da00 | 539 | positions in the global bitmaps. It is only created after all of |
6fb5fa3c DB |
540 | the all of stores have been scanned and we know which ones we |
541 | care about. */ | |
b8698a0f L |
542 | int *offset_map_n, *offset_map_p; |
543 | int offset_map_size_n, offset_map_size_p; | |
6fb5fa3c | 544 | }; |
da6603c6 | 545 | |
fcb87c50 | 546 | static object_allocator<group_info> group_info_pool ("rtx_group_info_pool"); |
6fb5fa3c | 547 | |
6fb5fa3c DB |
548 | /* Index into the rtx_group_vec. */ |
549 | static int rtx_group_next_id; | |
550 | ||
6fb5fa3c | 551 | |
fd6daec9 | 552 | static vec<group_info *> rtx_group_vec; |
6fb5fa3c DB |
553 | |
554 | ||
555 | /* This structure holds the set of changes that are being deferred | |
556 | when removing read operation. See replace_read. */ | |
b8698a0f | 557 | struct deferred_change |
6fb5fa3c DB |
558 | { |
559 | ||
560 | /* The mem that is being replaced. */ | |
561 | rtx *loc; | |
562 | ||
563 | /* The reg it is being replaced with. */ | |
564 | rtx reg; | |
565 | ||
566 | struct deferred_change *next; | |
567 | }; | |
568 | ||
fb0b2914 | 569 | static object_allocator<deferred_change> deferred_change_pool |
fcb87c50 | 570 | ("deferred_change_pool"); |
6fb5fa3c | 571 | |
fd6daec9 | 572 | static deferred_change *deferred_change_list = NULL; |
6fb5fa3c | 573 | |
e3b5732b | 574 | /* This is true except if cfun->stdarg -- i.e. we cannot do |
9dd9bf80 | 575 | this for vararg functions because they play games with the frame. */ |
6fb5fa3c DB |
576 | static bool stores_off_frame_dead_at_return; |
577 | ||
578 | /* Counter for stats. */ | |
b8698a0f L |
579 | static int globally_deleted; |
580 | static int locally_deleted; | |
b8698a0f | 581 | |
6fb5fa3c DB |
582 | static bitmap all_blocks; |
583 | ||
d26c7090 ER |
584 | /* Locations that are killed by calls in the global phase. */ |
585 | static bitmap kill_on_calls; | |
586 | ||
6fb5fa3c DB |
587 | /* The number of bits used in the global bitmaps. */ |
588 | static unsigned int current_position; | |
6fb5fa3c DB |
589 | \f |
590 | /*---------------------------------------------------------------------------- | |
591 | Zeroth step. | |
592 | ||
b8698a0f | 593 | Initialization. |
6fb5fa3c DB |
594 | ----------------------------------------------------------------------------*/ |
595 | ||
6fb5fa3c | 596 | |
6fb5fa3c DB |
597 | /* Hashtable callbacks for maintaining the "bases" field of |
598 | store_group_info, given that the addresses are function invariants. */ | |
599 | ||
8d67ee55 | 600 | struct invariant_group_base_hasher : nofree_ptr_hash <group_info> |
703c8606 | 601 | { |
67f58944 TS |
602 | static inline hashval_t hash (const group_info *); |
603 | static inline bool equal (const group_info *, const group_info *); | |
703c8606 LC |
604 | }; |
605 | ||
606 | inline bool | |
67f58944 TS |
607 | invariant_group_base_hasher::equal (const group_info *gi1, |
608 | const group_info *gi2) | |
6fb5fa3c | 609 | { |
6fb5fa3c DB |
610 | return rtx_equal_p (gi1->rtx_base, gi2->rtx_base); |
611 | } | |
612 | ||
703c8606 | 613 | inline hashval_t |
67f58944 | 614 | invariant_group_base_hasher::hash (const group_info *gi) |
6fb5fa3c | 615 | { |
6fb5fa3c DB |
616 | int do_not_record; |
617 | return hash_rtx (gi->rtx_base, Pmode, &do_not_record, NULL, false); | |
618 | } | |
619 | ||
703c8606 | 620 | /* Tables of group_info structures, hashed by base value. */ |
c203e8a7 | 621 | static hash_table<invariant_group_base_hasher> *rtx_group_table; |
703c8606 | 622 | |
6fb5fa3c DB |
623 | |
624 | /* Get the GROUP for BASE. Add a new group if it is not there. */ | |
625 | ||
fd6daec9 | 626 | static group_info * |
6fb5fa3c DB |
627 | get_group_info (rtx base) |
628 | { | |
b8698a0f | 629 | struct group_info tmp_gi; |
fd6daec9 | 630 | group_info *gi; |
703c8606 | 631 | group_info **slot; |
6fb5fa3c | 632 | |
ac6929b5 RB |
633 | gcc_assert (base != NULL_RTX); |
634 | ||
635 | /* Find the store_base_info structure for BASE, creating a new one | |
636 | if necessary. */ | |
637 | tmp_gi.rtx_base = base; | |
638 | slot = rtx_group_table->find_slot (&tmp_gi, INSERT); | |
639 | gi = *slot; | |
6fb5fa3c DB |
640 | |
641 | if (gi == NULL) | |
642 | { | |
fb0b2914 | 643 | *slot = gi = group_info_pool.allocate (); |
6fb5fa3c DB |
644 | gi->rtx_base = base; |
645 | gi->id = rtx_group_next_id++; | |
d32f725a | 646 | gi->base_mem = gen_rtx_MEM (BLKmode, base); |
6216f94e | 647 | gi->canon_base_addr = canon_rtx (base); |
3f9b14ff SB |
648 | gi->store1_n = BITMAP_ALLOC (&dse_bitmap_obstack); |
649 | gi->store1_p = BITMAP_ALLOC (&dse_bitmap_obstack); | |
650 | gi->store2_n = BITMAP_ALLOC (&dse_bitmap_obstack); | |
651 | gi->store2_p = BITMAP_ALLOC (&dse_bitmap_obstack); | |
652 | gi->escaped_p = BITMAP_ALLOC (&dse_bitmap_obstack); | |
653 | gi->escaped_n = BITMAP_ALLOC (&dse_bitmap_obstack); | |
654 | gi->group_kill = BITMAP_ALLOC (&dse_bitmap_obstack); | |
6fb5fa3c | 655 | gi->process_globally = false; |
b8698a0f | 656 | gi->frame_related = |
6fb5fa3c DB |
657 | (base == frame_pointer_rtx) || (base == hard_frame_pointer_rtx); |
658 | gi->offset_map_size_n = 0; | |
659 | gi->offset_map_size_p = 0; | |
660 | gi->offset_map_n = NULL; | |
661 | gi->offset_map_p = NULL; | |
9771b263 | 662 | rtx_group_vec.safe_push (gi); |
6fb5fa3c DB |
663 | } |
664 | ||
665 | return gi; | |
666 | } | |
667 | ||
668 | ||
669 | /* Initialization of data structures. */ | |
670 | ||
671 | static void | |
672 | dse_step0 (void) | |
673 | { | |
674 | locally_deleted = 0; | |
675 | globally_deleted = 0; | |
6fb5fa3c | 676 | |
3f9b14ff SB |
677 | bitmap_obstack_initialize (&dse_bitmap_obstack); |
678 | gcc_obstack_init (&dse_obstack); | |
679 | ||
680 | scratch = BITMAP_ALLOC (®_obstack); | |
681 | kill_on_calls = BITMAP_ALLOC (&dse_bitmap_obstack); | |
6fb5fa3c | 682 | |
6fb5fa3c | 683 | |
c203e8a7 | 684 | rtx_group_table = new hash_table<invariant_group_base_hasher> (11); |
6fb5fa3c | 685 | |
8b1c6fd7 | 686 | bb_table = XNEWVEC (bb_info_t, last_basic_block_for_fn (cfun)); |
6fb5fa3c DB |
687 | rtx_group_next_id = 0; |
688 | ||
e3b5732b | 689 | stores_off_frame_dead_at_return = !cfun->stdarg; |
6fb5fa3c DB |
690 | |
691 | init_alias_analysis (); | |
6fb5fa3c DB |
692 | } |
693 | ||
694 | ||
695 | \f | |
696 | /*---------------------------------------------------------------------------- | |
697 | First step. | |
698 | ||
699 | Scan all of the insns. Any random ordering of the blocks is fine. | |
0d52bcc1 | 700 | Each block is scanned in forward order to accommodate cselib which |
6fb5fa3c DB |
701 | is used to remove stores with non-constant bases. |
702 | ----------------------------------------------------------------------------*/ | |
703 | ||
704 | /* Delete all of the store_info recs from INSN_INFO. */ | |
705 | ||
b8698a0f | 706 | static void |
6fb5fa3c DB |
707 | free_store_info (insn_info_t insn_info) |
708 | { | |
fd6daec9 TS |
709 | store_info *cur = insn_info->store_rec; |
710 | while (cur) | |
6fb5fa3c | 711 | { |
fd6daec9 TS |
712 | store_info *next = cur->next; |
713 | if (cur->is_large) | |
714 | BITMAP_FREE (cur->positions_needed.large.bmap); | |
715 | if (cur->cse_base) | |
716 | cse_store_info_pool.remove (cur); | |
6fb5fa3c | 717 | else |
fd6daec9 TS |
718 | rtx_store_info_pool.remove (cur); |
719 | cur = next; | |
6fb5fa3c DB |
720 | } |
721 | ||
722 | insn_info->cannot_delete = true; | |
723 | insn_info->contains_cselib_groups = false; | |
724 | insn_info->store_rec = NULL; | |
725 | } | |
726 | ||
a79683d5 | 727 | struct note_add_store_info |
9e582b1d | 728 | { |
dc01c3d1 | 729 | rtx_insn *first, *current; |
9e582b1d JR |
730 | regset fixed_regs_live; |
731 | bool failure; | |
a79683d5 | 732 | }; |
9e582b1d JR |
733 | |
734 | /* Callback for emit_inc_dec_insn_before via note_stores. | |
735 | Check if a register is clobbered which is live afterwards. */ | |
736 | ||
737 | static void | |
738 | note_add_store (rtx loc, const_rtx expr ATTRIBUTE_UNUSED, void *data) | |
739 | { | |
dc01c3d1 | 740 | rtx_insn *insn; |
9e582b1d | 741 | note_add_store_info *info = (note_add_store_info *) data; |
9e582b1d JR |
742 | |
743 | if (!REG_P (loc)) | |
744 | return; | |
745 | ||
746 | /* If this register is referenced by the current or an earlier insn, | |
747 | that's OK. E.g. this applies to the register that is being incremented | |
748 | with this addition. */ | |
749 | for (insn = info->first; | |
750 | insn != NEXT_INSN (info->current); | |
751 | insn = NEXT_INSN (insn)) | |
752 | if (reg_referenced_p (loc, PATTERN (insn))) | |
753 | return; | |
754 | ||
755 | /* If we come here, we have a clobber of a register that's only OK | |
756 | if that register is not live. If we don't have liveness information | |
757 | available, fail now. */ | |
758 | if (!info->fixed_regs_live) | |
759 | { | |
53d1bae9 | 760 | info->failure = true; |
9e582b1d JR |
761 | return; |
762 | } | |
763 | /* Now check if this is a live fixed register. */ | |
53d1bae9 RS |
764 | unsigned int end_regno = END_REGNO (loc); |
765 | for (unsigned int regno = REGNO (loc); regno < end_regno; ++regno) | |
766 | if (REGNO_REG_SET_P (info->fixed_regs_live, regno)) | |
767 | info->failure = true; | |
9e582b1d JR |
768 | } |
769 | ||
4deef538 AO |
770 | /* Callback for for_each_inc_dec that emits an INSN that sets DEST to |
771 | SRC + SRCOFF before insn ARG. */ | |
6fb5fa3c DB |
772 | |
773 | static int | |
4deef538 AO |
774 | emit_inc_dec_insn_before (rtx mem ATTRIBUTE_UNUSED, |
775 | rtx op ATTRIBUTE_UNUSED, | |
776 | rtx dest, rtx src, rtx srcoff, void *arg) | |
6fb5fa3c | 777 | { |
9e582b1d | 778 | insn_info_t insn_info = (insn_info_t) arg; |
dc01c3d1 | 779 | rtx_insn *insn = insn_info->insn, *new_insn, *cur; |
9e582b1d | 780 | note_add_store_info info; |
b8698a0f | 781 | |
4deef538 AO |
782 | /* We can reuse all operands without copying, because we are about |
783 | to delete the insn that contained it. */ | |
9e582b1d | 784 | if (srcoff) |
ed079c4b JJ |
785 | { |
786 | start_sequence (); | |
787 | emit_insn (gen_add3_insn (dest, src, srcoff)); | |
788 | new_insn = get_insns (); | |
789 | end_sequence (); | |
790 | } | |
9e582b1d | 791 | else |
1476d1bd | 792 | new_insn = gen_move_insn (dest, src); |
9e582b1d JR |
793 | info.first = new_insn; |
794 | info.fixed_regs_live = insn_info->fixed_regs_live; | |
795 | info.failure = false; | |
796 | for (cur = new_insn; cur; cur = NEXT_INSN (cur)) | |
797 | { | |
798 | info.current = cur; | |
799 | note_stores (PATTERN (cur), note_add_store, &info); | |
800 | } | |
6fb5fa3c | 801 | |
9e582b1d JR |
802 | /* If a failure was flagged above, return 1 so that for_each_inc_dec will |
803 | return it immediately, communicating the failure to its caller. */ | |
804 | if (info.failure) | |
805 | return 1; | |
806 | ||
807 | emit_insn_before (new_insn, insn); | |
6fb5fa3c | 808 | |
8d8e205b | 809 | return 0; |
6fb5fa3c DB |
810 | } |
811 | ||
9e582b1d JR |
812 | /* Before we delete INSN_INFO->INSN, make sure that the auto inc/dec, if it |
813 | is there, is split into a separate insn. | |
814 | Return true on success (or if there was nothing to do), false on failure. */ | |
6fb5fa3c | 815 | |
9e582b1d JR |
816 | static bool |
817 | check_for_inc_dec_1 (insn_info_t insn_info) | |
6fb5fa3c | 818 | { |
dd60a84c | 819 | rtx_insn *insn = insn_info->insn; |
6fb5fa3c DB |
820 | rtx note = find_reg_note (insn, REG_INC, NULL_RTX); |
821 | if (note) | |
8d8e205b RS |
822 | return for_each_inc_dec (PATTERN (insn), emit_inc_dec_insn_before, |
823 | insn_info) == 0; | |
9e582b1d | 824 | return true; |
6fb5fa3c DB |
825 | } |
826 | ||
827 | ||
9e582b1d JR |
828 | /* Entry point for postreload. If you work on reload_cse, or you need this |
829 | anywhere else, consider if you can provide register liveness information | |
830 | and add a parameter to this function so that it can be passed down in | |
831 | insn_info.fixed_regs_live. */ | |
832 | bool | |
dd60a84c | 833 | check_for_inc_dec (rtx_insn *insn) |
9e582b1d | 834 | { |
da6603c6 | 835 | insn_info_type insn_info; |
9e582b1d JR |
836 | rtx note; |
837 | ||
838 | insn_info.insn = insn; | |
839 | insn_info.fixed_regs_live = NULL; | |
840 | note = find_reg_note (insn, REG_INC, NULL_RTX); | |
841 | if (note) | |
8d8e205b RS |
842 | return for_each_inc_dec (PATTERN (insn), emit_inc_dec_insn_before, |
843 | &insn_info) == 0; | |
9e582b1d JR |
844 | return true; |
845 | } | |
846 | ||
b8698a0f | 847 | /* Delete the insn and free all of the fields inside INSN_INFO. */ |
6fb5fa3c DB |
848 | |
849 | static void | |
850 | delete_dead_store_insn (insn_info_t insn_info) | |
851 | { | |
852 | read_info_t read_info; | |
853 | ||
854 | if (!dbg_cnt (dse)) | |
855 | return; | |
856 | ||
9e582b1d JR |
857 | if (!check_for_inc_dec_1 (insn_info)) |
858 | return; | |
456610d3 | 859 | if (dump_file && (dump_flags & TDF_DETAILS)) |
ac6929b5 RB |
860 | fprintf (dump_file, "Locally deleting insn %d\n", |
861 | INSN_UID (insn_info->insn)); | |
6fb5fa3c DB |
862 | |
863 | free_store_info (insn_info); | |
864 | read_info = insn_info->read_rec; | |
b8698a0f | 865 | |
6fb5fa3c DB |
866 | while (read_info) |
867 | { | |
868 | read_info_t next = read_info->next; | |
fb0b2914 | 869 | read_info_type_pool.remove (read_info); |
6fb5fa3c DB |
870 | read_info = next; |
871 | } | |
872 | insn_info->read_rec = NULL; | |
873 | ||
874 | delete_insn (insn_info->insn); | |
875 | locally_deleted++; | |
876 | insn_info->insn = NULL; | |
877 | ||
878 | insn_info->wild_read = false; | |
879 | } | |
880 | ||
88d8330d EB |
881 | /* Return whether DECL, a local variable, can possibly escape the current |
882 | function scope. */ | |
883 | ||
884 | static bool | |
885 | local_variable_can_escape (tree decl) | |
886 | { | |
887 | if (TREE_ADDRESSABLE (decl)) | |
888 | return true; | |
889 | ||
890 | /* If this is a partitioned variable, we need to consider all the variables | |
891 | in the partition. This is necessary because a store into one of them can | |
892 | be replaced with a store into another and this may not change the outcome | |
893 | of the escape analysis. */ | |
894 | if (cfun->gimple_df->decls_to_pointers != NULL) | |
895 | { | |
39c8aaa4 | 896 | tree *namep = cfun->gimple_df->decls_to_pointers->get (decl); |
88d8330d | 897 | if (namep) |
39c8aaa4 | 898 | return TREE_ADDRESSABLE (*namep); |
88d8330d EB |
899 | } |
900 | ||
901 | return false; | |
902 | } | |
903 | ||
904 | /* Return whether EXPR can possibly escape the current function scope. */ | |
905 | ||
d26c7090 ER |
906 | static bool |
907 | can_escape (tree expr) | |
908 | { | |
909 | tree base; | |
910 | if (!expr) | |
911 | return true; | |
912 | base = get_base_address (expr); | |
913 | if (DECL_P (base) | |
88d8330d | 914 | && !may_be_aliased (base) |
8813a647 | 915 | && !(VAR_P (base) |
88d8330d EB |
916 | && !DECL_EXTERNAL (base) |
917 | && !TREE_STATIC (base) | |
918 | && local_variable_can_escape (base))) | |
d26c7090 ER |
919 | return false; |
920 | return true; | |
921 | } | |
6fb5fa3c DB |
922 | |
923 | /* Set the store* bitmaps offset_map_size* fields in GROUP based on | |
924 | OFFSET and WIDTH. */ | |
925 | ||
926 | static void | |
fd6daec9 | 927 | set_usage_bits (group_info *group, HOST_WIDE_INT offset, HOST_WIDE_INT width, |
d26c7090 | 928 | tree expr) |
6fb5fa3c DB |
929 | { |
930 | HOST_WIDE_INT i; | |
d26c7090 | 931 | bool expr_escapes = can_escape (expr); |
8dd5516b | 932 | if (offset > -MAX_OFFSET && offset + width < MAX_OFFSET) |
6fb5fa3c DB |
933 | for (i=offset; i<offset+width; i++) |
934 | { | |
935 | bitmap store1; | |
936 | bitmap store2; | |
d26c7090 | 937 | bitmap escaped; |
6fb5fa3c DB |
938 | int ai; |
939 | if (i < 0) | |
940 | { | |
941 | store1 = group->store1_n; | |
942 | store2 = group->store2_n; | |
d26c7090 | 943 | escaped = group->escaped_n; |
6fb5fa3c DB |
944 | ai = -i; |
945 | } | |
946 | else | |
947 | { | |
948 | store1 = group->store1_p; | |
949 | store2 = group->store2_p; | |
d26c7090 | 950 | escaped = group->escaped_p; |
6fb5fa3c DB |
951 | ai = i; |
952 | } | |
b8698a0f | 953 | |
fcaa4ca4 | 954 | if (!bitmap_set_bit (store1, ai)) |
6fb5fa3c | 955 | bitmap_set_bit (store2, ai); |
b8698a0f | 956 | else |
6fb5fa3c | 957 | { |
6fb5fa3c DB |
958 | if (i < 0) |
959 | { | |
960 | if (group->offset_map_size_n < ai) | |
961 | group->offset_map_size_n = ai; | |
962 | } | |
963 | else | |
964 | { | |
965 | if (group->offset_map_size_p < ai) | |
966 | group->offset_map_size_p = ai; | |
967 | } | |
968 | } | |
d26c7090 ER |
969 | if (expr_escapes) |
970 | bitmap_set_bit (escaped, ai); | |
6fb5fa3c DB |
971 | } |
972 | } | |
973 | ||
d26c7090 ER |
974 | static void |
975 | reset_active_stores (void) | |
976 | { | |
977 | active_local_stores = NULL; | |
978 | active_local_stores_len = 0; | |
979 | } | |
6fb5fa3c | 980 | |
d26c7090 | 981 | /* Free all READ_REC of the LAST_INSN of BB_INFO. */ |
6fb5fa3c DB |
982 | |
983 | static void | |
d26c7090 | 984 | free_read_records (bb_info_t bb_info) |
6fb5fa3c DB |
985 | { |
986 | insn_info_t insn_info = bb_info->last_insn; | |
987 | read_info_t *ptr = &insn_info->read_rec; | |
6fb5fa3c DB |
988 | while (*ptr) |
989 | { | |
990 | read_info_t next = (*ptr)->next; | |
ac6929b5 RB |
991 | read_info_type_pool.remove (*ptr); |
992 | *ptr = next; | |
6fb5fa3c | 993 | } |
d26c7090 ER |
994 | } |
995 | ||
996 | /* Set the BB_INFO so that the last insn is marked as a wild read. */ | |
997 | ||
998 | static void | |
999 | add_wild_read (bb_info_t bb_info) | |
1000 | { | |
1001 | insn_info_t insn_info = bb_info->last_insn; | |
6fb5fa3c | 1002 | insn_info->wild_read = true; |
d26c7090 ER |
1003 | free_read_records (bb_info); |
1004 | reset_active_stores (); | |
6fb5fa3c DB |
1005 | } |
1006 | ||
d26c7090 ER |
1007 | /* Set the BB_INFO so that the last insn is marked as a wild read of |
1008 | non-frame locations. */ | |
1009 | ||
1010 | static void | |
1011 | add_non_frame_wild_read (bb_info_t bb_info) | |
1012 | { | |
1013 | insn_info_t insn_info = bb_info->last_insn; | |
1014 | insn_info->non_frame_wild_read = true; | |
1015 | free_read_records (bb_info); | |
1016 | reset_active_stores (); | |
1017 | } | |
6fb5fa3c | 1018 | |
50f0f366 EB |
1019 | /* Return true if X is a constant or one of the registers that behave |
1020 | as a constant over the life of a function. This is equivalent to | |
1021 | !rtx_varies_p for memory addresses. */ | |
6fb5fa3c DB |
1022 | |
1023 | static bool | |
1024 | const_or_frame_p (rtx x) | |
1025 | { | |
d8116890 KZ |
1026 | if (CONSTANT_P (x)) |
1027 | return true; | |
1028 | ||
1029 | if (GET_CODE (x) == REG) | |
6fb5fa3c | 1030 | { |
6fb5fa3c DB |
1031 | /* Note that we have to test for the actual rtx used for the frame |
1032 | and arg pointers and not just the register number in case we have | |
1033 | eliminated the frame and/or arg pointer and are using it | |
1034 | for pseudos. */ | |
1035 | if (x == frame_pointer_rtx || x == hard_frame_pointer_rtx | |
1036 | /* The arg pointer varies if it is not a fixed register. */ | |
1037 | || (x == arg_pointer_rtx && fixed_regs[ARG_POINTER_REGNUM]) | |
1038 | || x == pic_offset_table_rtx) | |
1039 | return true; | |
1040 | return false; | |
6fb5fa3c | 1041 | } |
da6603c6 | 1042 | |
d8116890 | 1043 | return false; |
6fb5fa3c DB |
1044 | } |
1045 | ||
b8698a0f L |
1046 | /* Take all reasonable action to put the address of MEM into the form |
1047 | that we can do analysis on. | |
6fb5fa3c DB |
1048 | |
1049 | The gold standard is to get the address into the form: address + | |
1050 | OFFSET where address is something that rtx_varies_p considers a | |
1051 | constant. When we can get the address in this form, we can do | |
1052 | global analysis on it. Note that for constant bases, address is | |
1053 | not actually returned, only the group_id. The address can be | |
1054 | obtained from that. | |
1055 | ||
1056 | If that fails, we try cselib to get a value we can at least use | |
b8698a0f L |
1057 | locally. If that fails we return false. |
1058 | ||
6fb5fa3c DB |
1059 | The GROUP_ID is set to -1 for cselib bases and the index of the |
1060 | group for non_varying bases. | |
1061 | ||
1062 | FOR_READ is true if this is a mem read and false if not. */ | |
1063 | ||
1064 | static bool | |
1065 | canon_address (rtx mem, | |
6fb5fa3c | 1066 | int *group_id, |
b8698a0f | 1067 | HOST_WIDE_INT *offset, |
6fb5fa3c DB |
1068 | cselib_val **base) |
1069 | { | |
ef4bddc2 | 1070 | machine_mode address_mode = get_address_mode (mem); |
6fb5fa3c DB |
1071 | rtx mem_address = XEXP (mem, 0); |
1072 | rtx expanded_address, address; | |
403c7520 JJ |
1073 | int expanded; |
1074 | ||
4deef538 | 1075 | cselib_lookup (mem_address, address_mode, 1, GET_MODE (mem)); |
6fb5fa3c | 1076 | |
456610d3 | 1077 | if (dump_file && (dump_flags & TDF_DETAILS)) |
6fb5fa3c DB |
1078 | { |
1079 | fprintf (dump_file, " mem: "); | |
1080 | print_inline_rtx (dump_file, mem_address, 0); | |
1081 | fprintf (dump_file, "\n"); | |
1082 | } | |
1083 | ||
403c7520 JJ |
1084 | /* First see if just canon_rtx (mem_address) is const or frame, |
1085 | if not, try cselib_expand_value_rtx and call canon_rtx on that. */ | |
1086 | address = NULL_RTX; | |
1087 | for (expanded = 0; expanded < 2; expanded++) | |
1088 | { | |
1089 | if (expanded) | |
1090 | { | |
1091 | /* Use cselib to replace all of the reg references with the full | |
b8698a0f | 1092 | expression. This will take care of the case where we have |
6fb5fa3c | 1093 | |
403c7520 JJ |
1094 | r_x = base + offset; |
1095 | val = *r_x; | |
b8698a0f L |
1096 | |
1097 | by making it into | |
6fb5fa3c | 1098 | |
403c7520 | 1099 | val = *(base + offset); */ |
6fb5fa3c | 1100 | |
403c7520 JJ |
1101 | expanded_address = cselib_expand_value_rtx (mem_address, |
1102 | scratch, 5); | |
6fb5fa3c | 1103 | |
403c7520 JJ |
1104 | /* If this fails, just go with the address from first |
1105 | iteration. */ | |
1106 | if (!expanded_address) | |
1107 | break; | |
1108 | } | |
1109 | else | |
1110 | expanded_address = mem_address; | |
6fb5fa3c | 1111 | |
403c7520 JJ |
1112 | /* Split the address into canonical BASE + OFFSET terms. */ |
1113 | address = canon_rtx (expanded_address); | |
6fb5fa3c | 1114 | |
403c7520 | 1115 | *offset = 0; |
6fb5fa3c | 1116 | |
456610d3 | 1117 | if (dump_file && (dump_flags & TDF_DETAILS)) |
403c7520 JJ |
1118 | { |
1119 | if (expanded) | |
1120 | { | |
1121 | fprintf (dump_file, "\n after cselib_expand address: "); | |
1122 | print_inline_rtx (dump_file, expanded_address, 0); | |
1123 | fprintf (dump_file, "\n"); | |
1124 | } | |
6fb5fa3c | 1125 | |
403c7520 JJ |
1126 | fprintf (dump_file, "\n after canon_rtx address: "); |
1127 | print_inline_rtx (dump_file, address, 0); | |
1128 | fprintf (dump_file, "\n"); | |
1129 | } | |
6fb5fa3c | 1130 | |
403c7520 JJ |
1131 | if (GET_CODE (address) == CONST) |
1132 | address = XEXP (address, 0); | |
6fb5fa3c | 1133 | |
403c7520 JJ |
1134 | if (GET_CODE (address) == PLUS |
1135 | && CONST_INT_P (XEXP (address, 1))) | |
1136 | { | |
1137 | *offset = INTVAL (XEXP (address, 1)); | |
1138 | address = XEXP (address, 0); | |
1139 | } | |
6fb5fa3c | 1140 | |
09e881c9 BE |
1141 | if (ADDR_SPACE_GENERIC_P (MEM_ADDR_SPACE (mem)) |
1142 | && const_or_frame_p (address)) | |
6fb5fa3c | 1143 | { |
fd6daec9 | 1144 | group_info *group = get_group_info (address); |
403c7520 | 1145 | |
456610d3 | 1146 | if (dump_file && (dump_flags & TDF_DETAILS)) |
403c7520 JJ |
1147 | fprintf (dump_file, " gid=%d offset=%d \n", |
1148 | group->id, (int)*offset); | |
1149 | *base = NULL; | |
1150 | *group_id = group->id; | |
1151 | return true; | |
6fb5fa3c | 1152 | } |
403c7520 JJ |
1153 | } |
1154 | ||
4deef538 | 1155 | *base = cselib_lookup (address, address_mode, true, GET_MODE (mem)); |
403c7520 JJ |
1156 | *group_id = -1; |
1157 | ||
1158 | if (*base == NULL) | |
1159 | { | |
456610d3 | 1160 | if (dump_file && (dump_flags & TDF_DETAILS)) |
403c7520 JJ |
1161 | fprintf (dump_file, " no cselib val - should be a wild read.\n"); |
1162 | return false; | |
6fb5fa3c | 1163 | } |
456610d3 | 1164 | if (dump_file && (dump_flags & TDF_DETAILS)) |
5440c0e7 AO |
1165 | fprintf (dump_file, " varying cselib base=%u:%u offset = %d\n", |
1166 | (*base)->uid, (*base)->hash, (int)*offset); | |
6fb5fa3c DB |
1167 | return true; |
1168 | } | |
1169 | ||
1170 | ||
1171 | /* Clear the rhs field from the active_local_stores array. */ | |
1172 | ||
1173 | static void | |
1174 | clear_rhs_from_active_local_stores (void) | |
1175 | { | |
1176 | insn_info_t ptr = active_local_stores; | |
1177 | ||
1178 | while (ptr) | |
1179 | { | |
fd6daec9 | 1180 | store_info *store_info = ptr->store_rec; |
6fb5fa3c DB |
1181 | /* Skip the clobbers. */ |
1182 | while (!store_info->is_set) | |
1183 | store_info = store_info->next; | |
1184 | ||
1185 | store_info->rhs = NULL; | |
8dd5516b | 1186 | store_info->const_rhs = NULL; |
6fb5fa3c DB |
1187 | |
1188 | ptr = ptr->next_local_store; | |
1189 | } | |
1190 | } | |
1191 | ||
1192 | ||
8dd5516b JJ |
1193 | /* Mark byte POS bytes from the beginning of store S_INFO as unneeded. */ |
1194 | ||
1195 | static inline void | |
fd6daec9 | 1196 | set_position_unneeded (store_info *s_info, int pos) |
8dd5516b JJ |
1197 | { |
1198 | if (__builtin_expect (s_info->is_large, false)) | |
1199 | { | |
fcaa4ca4 NF |
1200 | if (bitmap_set_bit (s_info->positions_needed.large.bmap, pos)) |
1201 | s_info->positions_needed.large.count++; | |
8dd5516b JJ |
1202 | } |
1203 | else | |
1204 | s_info->positions_needed.small_bitmask | |
fecfbfa4 | 1205 | &= ~(HOST_WIDE_INT_1U << pos); |
8dd5516b JJ |
1206 | } |
1207 | ||
1208 | /* Mark the whole store S_INFO as unneeded. */ | |
1209 | ||
1210 | static inline void | |
fd6daec9 | 1211 | set_all_positions_unneeded (store_info *s_info) |
8dd5516b JJ |
1212 | { |
1213 | if (__builtin_expect (s_info->is_large, false)) | |
1214 | { | |
1215 | int pos, end = s_info->end - s_info->begin; | |
1216 | for (pos = 0; pos < end; pos++) | |
dc491a25 | 1217 | bitmap_set_bit (s_info->positions_needed.large.bmap, pos); |
8dd5516b JJ |
1218 | s_info->positions_needed.large.count = end; |
1219 | } | |
1220 | else | |
07e96250 | 1221 | s_info->positions_needed.small_bitmask = HOST_WIDE_INT_0U; |
8dd5516b JJ |
1222 | } |
1223 | ||
1224 | /* Return TRUE if any bytes from S_INFO store are needed. */ | |
1225 | ||
1226 | static inline bool | |
fd6daec9 | 1227 | any_positions_needed_p (store_info *s_info) |
8dd5516b JJ |
1228 | { |
1229 | if (__builtin_expect (s_info->is_large, false)) | |
1230 | return (s_info->positions_needed.large.count | |
1231 | < s_info->end - s_info->begin); | |
1232 | else | |
07e96250 | 1233 | return (s_info->positions_needed.small_bitmask != HOST_WIDE_INT_0U); |
8dd5516b JJ |
1234 | } |
1235 | ||
1236 | /* Return TRUE if all bytes START through START+WIDTH-1 from S_INFO | |
1237 | store are needed. */ | |
1238 | ||
1239 | static inline bool | |
fd6daec9 | 1240 | all_positions_needed_p (store_info *s_info, int start, int width) |
8dd5516b JJ |
1241 | { |
1242 | if (__builtin_expect (s_info->is_large, false)) | |
1243 | { | |
1244 | int end = start + width; | |
1245 | while (start < end) | |
dc491a25 | 1246 | if (bitmap_bit_p (s_info->positions_needed.large.bmap, start++)) |
8dd5516b JJ |
1247 | return false; |
1248 | return true; | |
1249 | } | |
1250 | else | |
1251 | { | |
1252 | unsigned HOST_WIDE_INT mask = lowpart_bitmask (width) << start; | |
1253 | return (s_info->positions_needed.small_bitmask & mask) == mask; | |
1254 | } | |
1255 | } | |
1256 | ||
1257 | ||
fd6daec9 | 1258 | static rtx get_stored_val (store_info *, machine_mode, HOST_WIDE_INT, |
8dd5516b JJ |
1259 | HOST_WIDE_INT, basic_block, bool); |
1260 | ||
1261 | ||
6fb5fa3c DB |
1262 | /* BODY is an instruction pattern that belongs to INSN. Return 1 if |
1263 | there is a candidate store, after adding it to the appropriate | |
1264 | local store group if so. */ | |
1265 | ||
1266 | static int | |
1267 | record_store (rtx body, bb_info_t bb_info) | |
1268 | { | |
6216f94e | 1269 | rtx mem, rhs, const_rhs, mem_addr; |
6fb5fa3c DB |
1270 | HOST_WIDE_INT offset = 0; |
1271 | HOST_WIDE_INT width = 0; | |
6fb5fa3c | 1272 | insn_info_t insn_info = bb_info->last_insn; |
fd6daec9 | 1273 | store_info *store_info = NULL; |
6fb5fa3c DB |
1274 | int group_id; |
1275 | cselib_val *base = NULL; | |
8dd5516b | 1276 | insn_info_t ptr, last, redundant_reason; |
6fb5fa3c DB |
1277 | bool store_is_unused; |
1278 | ||
1279 | if (GET_CODE (body) != SET && GET_CODE (body) != CLOBBER) | |
1280 | return 0; | |
1281 | ||
8dd5516b JJ |
1282 | mem = SET_DEST (body); |
1283 | ||
6fb5fa3c DB |
1284 | /* If this is not used, then this cannot be used to keep the insn |
1285 | from being deleted. On the other hand, it does provide something | |
1286 | that can be used to prove that another store is dead. */ | |
1287 | store_is_unused | |
8dd5516b | 1288 | = (find_reg_note (insn_info->insn, REG_UNUSED, mem) != NULL); |
6fb5fa3c DB |
1289 | |
1290 | /* Check whether that value is a suitable memory location. */ | |
6fb5fa3c DB |
1291 | if (!MEM_P (mem)) |
1292 | { | |
1293 | /* If the set or clobber is unused, then it does not effect our | |
1294 | ability to get rid of the entire insn. */ | |
1295 | if (!store_is_unused) | |
1296 | insn_info->cannot_delete = true; | |
1297 | return 0; | |
1298 | } | |
1299 | ||
1300 | /* At this point we know mem is a mem. */ | |
1301 | if (GET_MODE (mem) == BLKmode) | |
1302 | { | |
1303 | if (GET_CODE (XEXP (mem, 0)) == SCRATCH) | |
1304 | { | |
456610d3 | 1305 | if (dump_file && (dump_flags & TDF_DETAILS)) |
6fb5fa3c DB |
1306 | fprintf (dump_file, " adding wild read for (clobber (mem:BLK (scratch))\n"); |
1307 | add_wild_read (bb_info); | |
1308 | insn_info->cannot_delete = true; | |
8dd5516b | 1309 | return 0; |
6fb5fa3c | 1310 | } |
8dd5516b JJ |
1311 | /* Handle (set (mem:BLK (addr) [... S36 ...]) (const_int 0)) |
1312 | as memset (addr, 0, 36); */ | |
f5541398 RS |
1313 | else if (!MEM_SIZE_KNOWN_P (mem) |
1314 | || MEM_SIZE (mem) <= 0 | |
1315 | || MEM_SIZE (mem) > MAX_OFFSET | |
8dd5516b | 1316 | || GET_CODE (body) != SET |
8dd5516b | 1317 | || !CONST_INT_P (SET_SRC (body))) |
6fb5fa3c | 1318 | { |
8dd5516b JJ |
1319 | if (!store_is_unused) |
1320 | { | |
1321 | /* If the set or clobber is unused, then it does not effect our | |
1322 | ability to get rid of the entire insn. */ | |
1323 | insn_info->cannot_delete = true; | |
1324 | clear_rhs_from_active_local_stores (); | |
1325 | } | |
1326 | return 0; | |
6fb5fa3c | 1327 | } |
6fb5fa3c DB |
1328 | } |
1329 | ||
1330 | /* We can still process a volatile mem, we just cannot delete it. */ | |
1331 | if (MEM_VOLATILE_P (mem)) | |
8dd5516b | 1332 | insn_info->cannot_delete = true; |
6fb5fa3c | 1333 | |
ac6929b5 | 1334 | if (!canon_address (mem, &group_id, &offset, &base)) |
6fb5fa3c DB |
1335 | { |
1336 | clear_rhs_from_active_local_stores (); | |
1337 | return 0; | |
1338 | } | |
1339 | ||
8dd5516b | 1340 | if (GET_MODE (mem) == BLKmode) |
f5541398 | 1341 | width = MEM_SIZE (mem); |
8dd5516b | 1342 | else |
6f557e0e | 1343 | width = GET_MODE_SIZE (GET_MODE (mem)); |
6fb5fa3c | 1344 | |
ac6929b5 | 1345 | if (group_id >= 0) |
6fb5fa3c DB |
1346 | { |
1347 | /* In the restrictive case where the base is a constant or the | |
1348 | frame pointer we can do global analysis. */ | |
b8698a0f | 1349 | |
fd6daec9 | 1350 | group_info *group |
9771b263 | 1351 | = rtx_group_vec[group_id]; |
d26c7090 | 1352 | tree expr = MEM_EXPR (mem); |
b8698a0f | 1353 | |
da6603c6 | 1354 | store_info = rtx_store_info_pool.allocate (); |
d26c7090 | 1355 | set_usage_bits (group, offset, width, expr); |
6fb5fa3c | 1356 | |
456610d3 | 1357 | if (dump_file && (dump_flags & TDF_DETAILS)) |
6fb5fa3c DB |
1358 | fprintf (dump_file, " processing const base store gid=%d[%d..%d)\n", |
1359 | group_id, (int)offset, (int)(offset+width)); | |
1360 | } | |
1361 | else | |
1362 | { | |
9e412ca3 | 1363 | if (may_be_sp_based_p (XEXP (mem, 0))) |
50f0f366 | 1364 | insn_info->stack_pointer_based = true; |
6fb5fa3c | 1365 | insn_info->contains_cselib_groups = true; |
50f0f366 | 1366 | |
da6603c6 | 1367 | store_info = cse_store_info_pool.allocate (); |
6fb5fa3c DB |
1368 | group_id = -1; |
1369 | ||
456610d3 | 1370 | if (dump_file && (dump_flags & TDF_DETAILS)) |
6fb5fa3c DB |
1371 | fprintf (dump_file, " processing cselib store [%d..%d)\n", |
1372 | (int)offset, (int)(offset+width)); | |
1373 | } | |
1374 | ||
8dd5516b JJ |
1375 | const_rhs = rhs = NULL_RTX; |
1376 | if (GET_CODE (body) == SET | |
1377 | /* No place to keep the value after ra. */ | |
1378 | && !reload_completed | |
1379 | && (REG_P (SET_SRC (body)) | |
1380 | || GET_CODE (SET_SRC (body)) == SUBREG | |
1381 | || CONSTANT_P (SET_SRC (body))) | |
1382 | && !MEM_VOLATILE_P (mem) | |
1383 | /* Sometimes the store and reload is used for truncation and | |
1384 | rounding. */ | |
1385 | && !(FLOAT_MODE_P (GET_MODE (mem)) && (flag_float_store))) | |
1386 | { | |
1387 | rhs = SET_SRC (body); | |
1388 | if (CONSTANT_P (rhs)) | |
1389 | const_rhs = rhs; | |
1390 | else if (body == PATTERN (insn_info->insn)) | |
1391 | { | |
1392 | rtx tem = find_reg_note (insn_info->insn, REG_EQUAL, NULL_RTX); | |
1393 | if (tem && CONSTANT_P (XEXP (tem, 0))) | |
1394 | const_rhs = XEXP (tem, 0); | |
1395 | } | |
1396 | if (const_rhs == NULL_RTX && REG_P (rhs)) | |
1397 | { | |
1398 | rtx tem = cselib_expand_value_rtx (rhs, scratch, 5); | |
1399 | ||
1400 | if (tem && CONSTANT_P (tem)) | |
1401 | const_rhs = tem; | |
1402 | } | |
1403 | } | |
1404 | ||
6fb5fa3c DB |
1405 | /* Check to see if this stores causes some other stores to be |
1406 | dead. */ | |
1407 | ptr = active_local_stores; | |
1408 | last = NULL; | |
8dd5516b | 1409 | redundant_reason = NULL; |
6216f94e | 1410 | mem = canon_rtx (mem); |
ac6929b5 RB |
1411 | |
1412 | if (group_id < 0) | |
1413 | mem_addr = base->val_rtx; | |
6216f94e JJ |
1414 | else |
1415 | { | |
ac6929b5 RB |
1416 | group_info *group = rtx_group_vec[group_id]; |
1417 | mem_addr = group->canon_base_addr; | |
6216f94e | 1418 | } |
ac6929b5 RB |
1419 | if (offset) |
1420 | mem_addr = plus_constant (get_address_mode (mem), mem_addr, offset); | |
6fb5fa3c DB |
1421 | |
1422 | while (ptr) | |
1423 | { | |
1424 | insn_info_t next = ptr->next_local_store; | |
fd6daec9 | 1425 | struct store_info *s_info = ptr->store_rec; |
60564289 | 1426 | bool del = true; |
6fb5fa3c DB |
1427 | |
1428 | /* Skip the clobbers. We delete the active insn if this insn | |
6ed3da00 | 1429 | shadows the set. To have been put on the active list, it |
6fb5fa3c DB |
1430 | has exactly on set. */ |
1431 | while (!s_info->is_set) | |
1432 | s_info = s_info->next; | |
1433 | ||
ac6929b5 | 1434 | if (s_info->group_id == group_id && s_info->cse_base == base) |
6fb5fa3c DB |
1435 | { |
1436 | HOST_WIDE_INT i; | |
456610d3 | 1437 | if (dump_file && (dump_flags & TDF_DETAILS)) |
6fb5fa3c | 1438 | fprintf (dump_file, " trying store in insn=%d gid=%d[%d..%d)\n", |
b8698a0f | 1439 | INSN_UID (ptr->insn), s_info->group_id, |
6fb5fa3c | 1440 | (int)s_info->begin, (int)s_info->end); |
8dd5516b JJ |
1441 | |
1442 | /* Even if PTR won't be eliminated as unneeded, if both | |
1443 | PTR and this insn store the same constant value, we might | |
1444 | eliminate this insn instead. */ | |
1445 | if (s_info->const_rhs | |
1446 | && const_rhs | |
1447 | && offset >= s_info->begin | |
1448 | && offset + width <= s_info->end | |
1449 | && all_positions_needed_p (s_info, offset - s_info->begin, | |
1450 | width)) | |
1451 | { | |
1452 | if (GET_MODE (mem) == BLKmode) | |
1453 | { | |
1454 | if (GET_MODE (s_info->mem) == BLKmode | |
1455 | && s_info->const_rhs == const_rhs) | |
1456 | redundant_reason = ptr; | |
1457 | } | |
1458 | else if (s_info->const_rhs == const0_rtx | |
1459 | && const_rhs == const0_rtx) | |
1460 | redundant_reason = ptr; | |
1461 | else | |
1462 | { | |
1463 | rtx val; | |
1464 | start_sequence (); | |
1465 | val = get_stored_val (s_info, GET_MODE (mem), | |
1466 | offset, offset + width, | |
1467 | BLOCK_FOR_INSN (insn_info->insn), | |
1468 | true); | |
1469 | if (get_insns () != NULL) | |
1470 | val = NULL_RTX; | |
1471 | end_sequence (); | |
1472 | if (val && rtx_equal_p (val, const_rhs)) | |
1473 | redundant_reason = ptr; | |
1474 | } | |
1475 | } | |
1476 | ||
1477 | for (i = MAX (offset, s_info->begin); | |
1478 | i < offset + width && i < s_info->end; | |
1479 | i++) | |
1480 | set_position_unneeded (s_info, i - s_info->begin); | |
6fb5fa3c DB |
1481 | } |
1482 | else if (s_info->rhs) | |
1483 | /* Need to see if it is possible for this store to overwrite | |
1484 | the value of store_info. If it is, set the rhs to NULL to | |
1485 | keep it from being used to remove a load. */ | |
1486 | { | |
43b9f499 RB |
1487 | if (canon_output_dependence (s_info->mem, true, |
1488 | mem, GET_MODE (mem), | |
1489 | mem_addr)) | |
8dd5516b JJ |
1490 | { |
1491 | s_info->rhs = NULL; | |
1492 | s_info->const_rhs = NULL; | |
1493 | } | |
6fb5fa3c | 1494 | } |
6216f94e | 1495 | |
6fb5fa3c DB |
1496 | /* An insn can be deleted if every position of every one of |
1497 | its s_infos is zero. */ | |
1b6fa860 | 1498 | if (any_positions_needed_p (s_info)) |
60564289 | 1499 | del = false; |
8dd5516b | 1500 | |
60564289 | 1501 | if (del) |
6fb5fa3c DB |
1502 | { |
1503 | insn_info_t insn_to_delete = ptr; | |
b8698a0f | 1504 | |
dabd47e7 | 1505 | active_local_stores_len--; |
6fb5fa3c DB |
1506 | if (last) |
1507 | last->next_local_store = ptr->next_local_store; | |
1508 | else | |
1509 | active_local_stores = ptr->next_local_store; | |
b8698a0f | 1510 | |
1b6fa860 JJ |
1511 | if (!insn_to_delete->cannot_delete) |
1512 | delete_dead_store_insn (insn_to_delete); | |
6fb5fa3c DB |
1513 | } |
1514 | else | |
1515 | last = ptr; | |
b8698a0f | 1516 | |
6fb5fa3c DB |
1517 | ptr = next; |
1518 | } | |
b8698a0f | 1519 | |
6fb5fa3c DB |
1520 | /* Finish filling in the store_info. */ |
1521 | store_info->next = insn_info->store_rec; | |
1522 | insn_info->store_rec = store_info; | |
6216f94e | 1523 | store_info->mem = mem; |
6216f94e | 1524 | store_info->mem_addr = mem_addr; |
6fb5fa3c | 1525 | store_info->cse_base = base; |
8dd5516b JJ |
1526 | if (width > HOST_BITS_PER_WIDE_INT) |
1527 | { | |
1528 | store_info->is_large = true; | |
1529 | store_info->positions_needed.large.count = 0; | |
3f9b14ff | 1530 | store_info->positions_needed.large.bmap = BITMAP_ALLOC (&dse_bitmap_obstack); |
8dd5516b JJ |
1531 | } |
1532 | else | |
1533 | { | |
1534 | store_info->is_large = false; | |
1535 | store_info->positions_needed.small_bitmask = lowpart_bitmask (width); | |
1536 | } | |
6fb5fa3c DB |
1537 | store_info->group_id = group_id; |
1538 | store_info->begin = offset; | |
1539 | store_info->end = offset + width; | |
1540 | store_info->is_set = GET_CODE (body) == SET; | |
8dd5516b JJ |
1541 | store_info->rhs = rhs; |
1542 | store_info->const_rhs = const_rhs; | |
1543 | store_info->redundant_reason = redundant_reason; | |
6fb5fa3c | 1544 | |
6fb5fa3c DB |
1545 | /* If this is a clobber, we return 0. We will only be able to |
1546 | delete this insn if there is only one store USED store, but we | |
1547 | can use the clobber to delete other stores earlier. */ | |
1548 | return store_info->is_set ? 1 : 0; | |
1549 | } | |
1550 | ||
1551 | ||
1552 | static void | |
1553 | dump_insn_info (const char * start, insn_info_t insn_info) | |
1554 | { | |
b8698a0f | 1555 | fprintf (dump_file, "%s insn=%d %s\n", start, |
6fb5fa3c DB |
1556 | INSN_UID (insn_info->insn), |
1557 | insn_info->store_rec ? "has store" : "naked"); | |
1558 | } | |
1559 | ||
1560 | ||
8660aaae EC |
1561 | /* If the modes are different and the value's source and target do not |
1562 | line up, we need to extract the value from lower part of the rhs of | |
1563 | the store, shift it, and then put it into a form that can be shoved | |
1564 | into the read_insn. This function generates a right SHIFT of a | |
1565 | value that is at least ACCESS_SIZE bytes wide of READ_MODE. The | |
1566 | shift sequence is returned or NULL if we failed to find a | |
1567 | shift. */ | |
1568 | ||
1569 | static rtx | |
18b526e8 | 1570 | find_shift_sequence (int access_size, |
fd6daec9 | 1571 | store_info *store_info, |
ef4bddc2 | 1572 | machine_mode read_mode, |
8dd5516b | 1573 | int shift, bool speed, bool require_cst) |
8660aaae | 1574 | { |
ef4bddc2 | 1575 | machine_mode store_mode = GET_MODE (store_info->mem); |
f67f4dff | 1576 | scalar_int_mode new_mode; |
18b526e8 | 1577 | rtx read_reg = NULL; |
8660aaae EC |
1578 | |
1579 | /* Some machines like the x86 have shift insns for each size of | |
1580 | operand. Other machines like the ppc or the ia-64 may only have | |
1581 | shift insns that shift values within 32 or 64 bit registers. | |
1582 | This loop tries to find the smallest shift insn that will right | |
1583 | justify the value we want to read but is available in one insn on | |
1584 | the machine. */ | |
1585 | ||
f67f4dff RS |
1586 | opt_scalar_int_mode new_mode_iter; |
1587 | FOR_EACH_MODE_FROM (new_mode_iter, | |
1588 | smallest_int_mode_for_size (access_size * BITS_PER_UNIT)) | |
8660aaae | 1589 | { |
dc01c3d1 DM |
1590 | rtx target, new_reg, new_lhs; |
1591 | rtx_insn *shift_seq, *insn; | |
d898d29b | 1592 | int cost; |
348eea5f | 1593 | |
f67f4dff | 1594 | new_mode = new_mode_iter.require (); |
c94843d2 RS |
1595 | if (GET_MODE_BITSIZE (new_mode) > BITS_PER_WORD) |
1596 | break; | |
1597 | ||
72a2609f JJ |
1598 | /* If a constant was stored into memory, try to simplify it here, |
1599 | otherwise the cost of the shift might preclude this optimization | |
1600 | e.g. at -Os, even when no actual shift will be needed. */ | |
8dd5516b | 1601 | if (store_info->const_rhs) |
72a2609f JJ |
1602 | { |
1603 | unsigned int byte = subreg_lowpart_offset (new_mode, store_mode); | |
8dd5516b JJ |
1604 | rtx ret = simplify_subreg (new_mode, store_info->const_rhs, |
1605 | store_mode, byte); | |
72a2609f JJ |
1606 | if (ret && CONSTANT_P (ret)) |
1607 | { | |
1608 | ret = simplify_const_binary_operation (LSHIFTRT, new_mode, | |
1609 | ret, GEN_INT (shift)); | |
1610 | if (ret && CONSTANT_P (ret)) | |
1611 | { | |
1612 | byte = subreg_lowpart_offset (read_mode, new_mode); | |
1613 | ret = simplify_subreg (read_mode, ret, new_mode, byte); | |
1614 | if (ret && CONSTANT_P (ret) | |
e548c9df AM |
1615 | && (set_src_cost (ret, read_mode, speed) |
1616 | <= COSTS_N_INSNS (1))) | |
72a2609f JJ |
1617 | return ret; |
1618 | } | |
1619 | } | |
1620 | } | |
1621 | ||
8dd5516b JJ |
1622 | if (require_cst) |
1623 | return NULL_RTX; | |
1624 | ||
18b526e8 RS |
1625 | /* Try a wider mode if truncating the store mode to NEW_MODE |
1626 | requires a real instruction. */ | |
1627 | if (GET_MODE_BITSIZE (new_mode) < GET_MODE_BITSIZE (store_mode) | |
d0edd768 | 1628 | && !TRULY_NOOP_TRUNCATION_MODES_P (new_mode, store_mode)) |
348eea5f RS |
1629 | continue; |
1630 | ||
18b526e8 RS |
1631 | /* Also try a wider mode if the necessary punning is either not |
1632 | desirable or not possible. */ | |
1633 | if (!CONSTANT_P (store_info->rhs) | |
99e1629f | 1634 | && !targetm.modes_tieable_p (new_mode, store_mode)) |
18b526e8 | 1635 | continue; |
18b526e8 | 1636 | |
348eea5f | 1637 | new_reg = gen_reg_rtx (new_mode); |
8660aaae EC |
1638 | |
1639 | start_sequence (); | |
1640 | ||
1641 | /* In theory we could also check for an ashr. Ian Taylor knows | |
1642 | of one dsp where the cost of these two was not the same. But | |
1643 | this really is a rare case anyway. */ | |
1644 | target = expand_binop (new_mode, lshr_optab, new_reg, | |
1645 | GEN_INT (shift), new_reg, 1, OPTAB_DIRECT); | |
1646 | ||
c6f3019a RS |
1647 | shift_seq = get_insns (); |
1648 | end_sequence (); | |
8660aaae | 1649 | |
c6f3019a RS |
1650 | if (target != new_reg || shift_seq == NULL) |
1651 | continue; | |
1652 | ||
1653 | cost = 0; | |
1654 | for (insn = shift_seq; insn != NULL_RTX; insn = NEXT_INSN (insn)) | |
1655 | if (INSN_P (insn)) | |
d09e78e8 | 1656 | cost += insn_cost (insn, speed); |
c6f3019a RS |
1657 | |
1658 | /* The computation up to here is essentially independent | |
1659 | of the arguments and could be precomputed. It may | |
1660 | not be worth doing so. We could precompute if | |
1661 | worthwhile or at least cache the results. The result | |
06acf7d0 RS |
1662 | technically depends on both SHIFT and ACCESS_SIZE, |
1663 | but in practice the answer will depend only on ACCESS_SIZE. */ | |
c6f3019a RS |
1664 | |
1665 | if (cost > COSTS_N_INSNS (1)) | |
1666 | continue; | |
1667 | ||
d898d29b JJ |
1668 | new_lhs = extract_low_bits (new_mode, store_mode, |
1669 | copy_rtx (store_info->rhs)); | |
1670 | if (new_lhs == NULL_RTX) | |
1671 | continue; | |
1672 | ||
c6f3019a RS |
1673 | /* We found an acceptable shift. Generate a move to |
1674 | take the value from the store and put it into the | |
1675 | shift pseudo, then shift it, then generate another | |
1676 | move to put in into the target of the read. */ | |
18b526e8 | 1677 | emit_move_insn (new_reg, new_lhs); |
c6f3019a | 1678 | emit_insn (shift_seq); |
18b526e8 | 1679 | read_reg = extract_low_bits (read_mode, new_mode, new_reg); |
c6f3019a | 1680 | break; |
8660aaae EC |
1681 | } |
1682 | ||
18b526e8 | 1683 | return read_reg; |
8660aaae EC |
1684 | } |
1685 | ||
1686 | ||
02b47899 KZ |
1687 | /* Call back for note_stores to find the hard regs set or clobbered by |
1688 | insn. Data is a bitmap of the hardregs set so far. */ | |
1689 | ||
1690 | static void | |
1691 | look_for_hardregs (rtx x, const_rtx pat ATTRIBUTE_UNUSED, void *data) | |
1692 | { | |
1693 | bitmap regs_set = (bitmap) data; | |
1694 | ||
1695 | if (REG_P (x) | |
f773c2bd | 1696 | && HARD_REGISTER_P (x)) |
dc8afb70 | 1697 | bitmap_set_range (regs_set, REGNO (x), REG_NREGS (x)); |
02b47899 KZ |
1698 | } |
1699 | ||
8dd5516b JJ |
1700 | /* Helper function for replace_read and record_store. |
1701 | Attempt to return a value stored in STORE_INFO, from READ_BEGIN | |
1702 | to one before READ_END bytes read in READ_MODE. Return NULL | |
1703 | if not successful. If REQUIRE_CST is true, return always constant. */ | |
1704 | ||
1705 | static rtx | |
fd6daec9 | 1706 | get_stored_val (store_info *store_info, machine_mode read_mode, |
8dd5516b JJ |
1707 | HOST_WIDE_INT read_begin, HOST_WIDE_INT read_end, |
1708 | basic_block bb, bool require_cst) | |
1709 | { | |
ef4bddc2 | 1710 | machine_mode store_mode = GET_MODE (store_info->mem); |
8dd5516b JJ |
1711 | int shift; |
1712 | int access_size; /* In bytes. */ | |
1713 | rtx read_reg; | |
1714 | ||
1715 | /* To get here the read is within the boundaries of the write so | |
1716 | shift will never be negative. Start out with the shift being in | |
1717 | bytes. */ | |
1718 | if (store_mode == BLKmode) | |
1719 | shift = 0; | |
1720 | else if (BYTES_BIG_ENDIAN) | |
1721 | shift = store_info->end - read_end; | |
1722 | else | |
1723 | shift = read_begin - store_info->begin; | |
1724 | ||
1725 | access_size = shift + GET_MODE_SIZE (read_mode); | |
1726 | ||
1727 | /* From now on it is bits. */ | |
1728 | shift *= BITS_PER_UNIT; | |
1729 | ||
1730 | if (shift) | |
1731 | read_reg = find_shift_sequence (access_size, store_info, read_mode, shift, | |
1732 | optimize_bb_for_speed_p (bb), | |
1733 | require_cst); | |
1734 | else if (store_mode == BLKmode) | |
1735 | { | |
1736 | /* The store is a memset (addr, const_val, const_size). */ | |
1737 | gcc_assert (CONST_INT_P (store_info->rhs)); | |
304b9962 RS |
1738 | scalar_int_mode int_store_mode; |
1739 | if (!int_mode_for_mode (read_mode).exists (&int_store_mode)) | |
8dd5516b JJ |
1740 | read_reg = NULL_RTX; |
1741 | else if (store_info->rhs == const0_rtx) | |
304b9962 RS |
1742 | read_reg = extract_low_bits (read_mode, int_store_mode, const0_rtx); |
1743 | else if (GET_MODE_BITSIZE (int_store_mode) > HOST_BITS_PER_WIDE_INT | |
8dd5516b JJ |
1744 | || BITS_PER_UNIT >= HOST_BITS_PER_WIDE_INT) |
1745 | read_reg = NULL_RTX; | |
1746 | else | |
1747 | { | |
1748 | unsigned HOST_WIDE_INT c | |
1749 | = INTVAL (store_info->rhs) | |
fecfbfa4 | 1750 | & ((HOST_WIDE_INT_1 << BITS_PER_UNIT) - 1); |
8dd5516b JJ |
1751 | int shift = BITS_PER_UNIT; |
1752 | while (shift < HOST_BITS_PER_WIDE_INT) | |
1753 | { | |
1754 | c |= (c << shift); | |
1755 | shift <<= 1; | |
1756 | } | |
304b9962 RS |
1757 | read_reg = gen_int_mode (c, int_store_mode); |
1758 | read_reg = extract_low_bits (read_mode, int_store_mode, read_reg); | |
8dd5516b JJ |
1759 | } |
1760 | } | |
1761 | else if (store_info->const_rhs | |
1762 | && (require_cst | |
1763 | || GET_MODE_CLASS (read_mode) != GET_MODE_CLASS (store_mode))) | |
1764 | read_reg = extract_low_bits (read_mode, store_mode, | |
1765 | copy_rtx (store_info->const_rhs)); | |
1766 | else | |
1767 | read_reg = extract_low_bits (read_mode, store_mode, | |
1768 | copy_rtx (store_info->rhs)); | |
1769 | if (require_cst && read_reg && !CONSTANT_P (read_reg)) | |
1770 | read_reg = NULL_RTX; | |
1771 | return read_reg; | |
1772 | } | |
02b47899 | 1773 | |
6fb5fa3c DB |
1774 | /* Take a sequence of: |
1775 | A <- r1 | |
1776 | ... | |
1777 | ... <- A | |
1778 | ||
b8698a0f | 1779 | and change it into |
6fb5fa3c DB |
1780 | r2 <- r1 |
1781 | A <- r1 | |
1782 | ... | |
1783 | ... <- r2 | |
1784 | ||
8660aaae EC |
1785 | or |
1786 | ||
1787 | r3 <- extract (r1) | |
1788 | r3 <- r3 >> shift | |
1789 | r2 <- extract (r3) | |
1790 | ... <- r2 | |
1791 | ||
1792 | or | |
1793 | ||
1794 | r2 <- extract (r1) | |
1795 | ... <- r2 | |
1796 | ||
1797 | Depending on the alignment and the mode of the store and | |
1798 | subsequent load. | |
1799 | ||
1800 | ||
1801 | The STORE_INFO and STORE_INSN are for the store and READ_INFO | |
6fb5fa3c DB |
1802 | and READ_INSN are for the read. Return true if the replacement |
1803 | went ok. */ | |
1804 | ||
1805 | static bool | |
fd6daec9 | 1806 | replace_read (store_info *store_info, insn_info_t store_insn, |
8dd5516b JJ |
1807 | read_info_t read_info, insn_info_t read_insn, rtx *loc, |
1808 | bitmap regs_live) | |
6fb5fa3c | 1809 | { |
ef4bddc2 RS |
1810 | machine_mode store_mode = GET_MODE (store_info->mem); |
1811 | machine_mode read_mode = GET_MODE (read_info->mem); | |
dc01c3d1 DM |
1812 | rtx_insn *insns, *this_insn; |
1813 | rtx read_reg; | |
8dd5516b | 1814 | basic_block bb; |
8660aaae | 1815 | |
6fb5fa3c DB |
1816 | if (!dbg_cnt (dse)) |
1817 | return false; | |
1818 | ||
18b526e8 RS |
1819 | /* Create a sequence of instructions to set up the read register. |
1820 | This sequence goes immediately before the store and its result | |
1821 | is read by the load. | |
1822 | ||
1823 | We need to keep this in perspective. We are replacing a read | |
8660aaae EC |
1824 | with a sequence of insns, but the read will almost certainly be |
1825 | in cache, so it is not going to be an expensive one. Thus, we | |
1826 | are not willing to do a multi insn shift or worse a subroutine | |
1827 | call to get rid of the read. */ | |
456610d3 | 1828 | if (dump_file && (dump_flags & TDF_DETAILS)) |
18b526e8 RS |
1829 | fprintf (dump_file, "trying to replace %smode load in insn %d" |
1830 | " from %smode store in insn %d\n", | |
1831 | GET_MODE_NAME (read_mode), INSN_UID (read_insn->insn), | |
1832 | GET_MODE_NAME (store_mode), INSN_UID (store_insn->insn)); | |
1833 | start_sequence (); | |
8dd5516b JJ |
1834 | bb = BLOCK_FOR_INSN (read_insn->insn); |
1835 | read_reg = get_stored_val (store_info, | |
1836 | read_mode, read_info->begin, read_info->end, | |
1837 | bb, false); | |
18b526e8 | 1838 | if (read_reg == NULL_RTX) |
8660aaae | 1839 | { |
18b526e8 | 1840 | end_sequence (); |
456610d3 | 1841 | if (dump_file && (dump_flags & TDF_DETAILS)) |
18b526e8 RS |
1842 | fprintf (dump_file, " -- could not extract bits of stored value\n"); |
1843 | return false; | |
8660aaae | 1844 | } |
18b526e8 RS |
1845 | /* Force the value into a new register so that it won't be clobbered |
1846 | between the store and the load. */ | |
1847 | read_reg = copy_to_mode_reg (read_mode, read_reg); | |
1848 | insns = get_insns (); | |
1849 | end_sequence (); | |
8660aaae | 1850 | |
02b47899 KZ |
1851 | if (insns != NULL_RTX) |
1852 | { | |
1853 | /* Now we have to scan the set of new instructions to see if the | |
1854 | sequence contains and sets of hardregs that happened to be | |
1855 | live at this point. For instance, this can happen if one of | |
1856 | the insns sets the CC and the CC happened to be live at that | |
1857 | point. This does occasionally happen, see PR 37922. */ | |
3f9b14ff | 1858 | bitmap regs_set = BITMAP_ALLOC (®_obstack); |
02b47899 KZ |
1859 | |
1860 | for (this_insn = insns; this_insn != NULL_RTX; this_insn = NEXT_INSN (this_insn)) | |
1861 | note_stores (PATTERN (this_insn), look_for_hardregs, regs_set); | |
b8698a0f | 1862 | |
02b47899 KZ |
1863 | bitmap_and_into (regs_set, regs_live); |
1864 | if (!bitmap_empty_p (regs_set)) | |
1865 | { | |
456610d3 | 1866 | if (dump_file && (dump_flags & TDF_DETAILS)) |
02b47899 | 1867 | { |
b8698a0f | 1868 | fprintf (dump_file, |
02b47899 KZ |
1869 | "abandoning replacement because sequence clobbers live hardregs:"); |
1870 | df_print_regset (dump_file, regs_set); | |
1871 | } | |
b8698a0f | 1872 | |
02b47899 KZ |
1873 | BITMAP_FREE (regs_set); |
1874 | return false; | |
1875 | } | |
1876 | BITMAP_FREE (regs_set); | |
1877 | } | |
1878 | ||
8660aaae | 1879 | if (validate_change (read_insn->insn, loc, read_reg, 0)) |
6fb5fa3c | 1880 | { |
fd6daec9 | 1881 | deferred_change *change = deferred_change_pool.allocate (); |
b8698a0f | 1882 | |
8660aaae EC |
1883 | /* Insert this right before the store insn where it will be safe |
1884 | from later insns that might change it before the read. */ | |
1885 | emit_insn_before (insns, store_insn->insn); | |
b8698a0f | 1886 | |
8660aaae EC |
1887 | /* And now for the kludge part: cselib croaks if you just |
1888 | return at this point. There are two reasons for this: | |
b8698a0f | 1889 | |
8660aaae EC |
1890 | 1) Cselib has an idea of how many pseudos there are and |
1891 | that does not include the new ones we just added. | |
b8698a0f | 1892 | |
8660aaae EC |
1893 | 2) Cselib does not know about the move insn we added |
1894 | above the store_info, and there is no way to tell it | |
1895 | about it, because it has "moved on". | |
b8698a0f | 1896 | |
8660aaae EC |
1897 | Problem (1) is fixable with a certain amount of engineering. |
1898 | Problem (2) is requires starting the bb from scratch. This | |
1899 | could be expensive. | |
b8698a0f | 1900 | |
8660aaae EC |
1901 | So we are just going to have to lie. The move/extraction |
1902 | insns are not really an issue, cselib did not see them. But | |
1903 | the use of the new pseudo read_insn is a real problem because | |
1904 | cselib has not scanned this insn. The way that we solve this | |
1905 | problem is that we are just going to put the mem back for now | |
1906 | and when we are finished with the block, we undo this. We | |
1907 | keep a table of mems to get rid of. At the end of the basic | |
1908 | block we can put them back. */ | |
b8698a0f | 1909 | |
8660aaae | 1910 | *loc = read_info->mem; |
da6603c6 ML |
1911 | change->next = deferred_change_list; |
1912 | deferred_change_list = change; | |
1913 | change->loc = loc; | |
1914 | change->reg = read_reg; | |
b8698a0f | 1915 | |
8660aaae EC |
1916 | /* Get rid of the read_info, from the point of view of the |
1917 | rest of dse, play like this read never happened. */ | |
1918 | read_insn->read_rec = read_info->next; | |
fb0b2914 | 1919 | read_info_type_pool.remove (read_info); |
456610d3 | 1920 | if (dump_file && (dump_flags & TDF_DETAILS)) |
18b526e8 RS |
1921 | { |
1922 | fprintf (dump_file, " -- replaced the loaded MEM with "); | |
1923 | print_simple_rtl (dump_file, read_reg); | |
1924 | fprintf (dump_file, "\n"); | |
1925 | } | |
8660aaae | 1926 | return true; |
6fb5fa3c | 1927 | } |
b8698a0f | 1928 | else |
6fb5fa3c | 1929 | { |
456610d3 | 1930 | if (dump_file && (dump_flags & TDF_DETAILS)) |
18b526e8 RS |
1931 | { |
1932 | fprintf (dump_file, " -- replacing the loaded MEM with "); | |
1933 | print_simple_rtl (dump_file, read_reg); | |
1934 | fprintf (dump_file, " led to an invalid instruction\n"); | |
1935 | } | |
6fb5fa3c DB |
1936 | return false; |
1937 | } | |
1938 | } | |
1939 | ||
d7111da8 RS |
1940 | /* Check the address of MEM *LOC and kill any appropriate stores that may |
1941 | be active. */ | |
6fb5fa3c | 1942 | |
d7111da8 RS |
1943 | static void |
1944 | check_mem_read_rtx (rtx *loc, bb_info_t bb_info) | |
6fb5fa3c | 1945 | { |
6216f94e | 1946 | rtx mem = *loc, mem_addr; |
6fb5fa3c DB |
1947 | insn_info_t insn_info; |
1948 | HOST_WIDE_INT offset = 0; | |
1949 | HOST_WIDE_INT width = 0; | |
b8698a0f | 1950 | cselib_val *base = NULL; |
6fb5fa3c DB |
1951 | int group_id; |
1952 | read_info_t read_info; | |
1953 | ||
6fb5fa3c DB |
1954 | insn_info = bb_info->last_insn; |
1955 | ||
1956 | if ((MEM_ALIAS_SET (mem) == ALIAS_SET_MEMORY_BARRIER) | |
1957 | || (MEM_VOLATILE_P (mem))) | |
1958 | { | |
456610d3 | 1959 | if (dump_file && (dump_flags & TDF_DETAILS)) |
6fb5fa3c DB |
1960 | fprintf (dump_file, " adding wild read, volatile or barrier.\n"); |
1961 | add_wild_read (bb_info); | |
1962 | insn_info->cannot_delete = true; | |
d7111da8 | 1963 | return; |
6fb5fa3c DB |
1964 | } |
1965 | ||
1966 | /* If it is reading readonly mem, then there can be no conflict with | |
1967 | another write. */ | |
1968 | if (MEM_READONLY_P (mem)) | |
d7111da8 | 1969 | return; |
6fb5fa3c | 1970 | |
ac6929b5 | 1971 | if (!canon_address (mem, &group_id, &offset, &base)) |
6fb5fa3c | 1972 | { |
456610d3 | 1973 | if (dump_file && (dump_flags & TDF_DETAILS)) |
6fb5fa3c DB |
1974 | fprintf (dump_file, " adding wild read, canon_address failure.\n"); |
1975 | add_wild_read (bb_info); | |
d7111da8 | 1976 | return; |
6fb5fa3c DB |
1977 | } |
1978 | ||
1979 | if (GET_MODE (mem) == BLKmode) | |
1980 | width = -1; | |
1981 | else | |
1982 | width = GET_MODE_SIZE (GET_MODE (mem)); | |
1983 | ||
938f9248 ML |
1984 | if (offset > HOST_WIDE_INT_MAX - width) |
1985 | { | |
1986 | clear_rhs_from_active_local_stores (); | |
1987 | return; | |
1988 | } | |
1989 | ||
fb0b2914 | 1990 | read_info = read_info_type_pool.allocate (); |
6fb5fa3c DB |
1991 | read_info->group_id = group_id; |
1992 | read_info->mem = mem; | |
6fb5fa3c DB |
1993 | read_info->begin = offset; |
1994 | read_info->end = offset + width; | |
1995 | read_info->next = insn_info->read_rec; | |
1996 | insn_info->read_rec = read_info; | |
ac6929b5 RB |
1997 | if (group_id < 0) |
1998 | mem_addr = base->val_rtx; | |
6216f94e JJ |
1999 | else |
2000 | { | |
ac6929b5 RB |
2001 | group_info *group = rtx_group_vec[group_id]; |
2002 | mem_addr = group->canon_base_addr; | |
6216f94e | 2003 | } |
ac6929b5 RB |
2004 | if (offset) |
2005 | mem_addr = plus_constant (get_address_mode (mem), mem_addr, offset); | |
6fb5fa3c | 2006 | |
ac6929b5 | 2007 | if (group_id >= 0) |
6fb5fa3c DB |
2008 | { |
2009 | /* This is the restricted case where the base is a constant or | |
2010 | the frame pointer and offset is a constant. */ | |
2011 | insn_info_t i_ptr = active_local_stores; | |
2012 | insn_info_t last = NULL; | |
b8698a0f | 2013 | |
456610d3 | 2014 | if (dump_file && (dump_flags & TDF_DETAILS)) |
6fb5fa3c DB |
2015 | { |
2016 | if (width == -1) | |
2017 | fprintf (dump_file, " processing const load gid=%d[BLK]\n", | |
2018 | group_id); | |
2019 | else | |
2020 | fprintf (dump_file, " processing const load gid=%d[%d..%d)\n", | |
2021 | group_id, (int)offset, (int)(offset+width)); | |
2022 | } | |
2023 | ||
2024 | while (i_ptr) | |
2025 | { | |
2026 | bool remove = false; | |
fd6daec9 | 2027 | store_info *store_info = i_ptr->store_rec; |
b8698a0f | 2028 | |
6fb5fa3c DB |
2029 | /* Skip the clobbers. */ |
2030 | while (!store_info->is_set) | |
2031 | store_info = store_info->next; | |
b8698a0f | 2032 | |
6fb5fa3c DB |
2033 | /* There are three cases here. */ |
2034 | if (store_info->group_id < 0) | |
2035 | /* We have a cselib store followed by a read from a | |
2036 | const base. */ | |
b8698a0f L |
2037 | remove |
2038 | = canon_true_dependence (store_info->mem, | |
6fb5fa3c DB |
2039 | GET_MODE (store_info->mem), |
2040 | store_info->mem_addr, | |
53d9622b | 2041 | mem, mem_addr); |
b8698a0f | 2042 | |
6fb5fa3c DB |
2043 | else if (group_id == store_info->group_id) |
2044 | { | |
2045 | /* This is a block mode load. We may get lucky and | |
2046 | canon_true_dependence may save the day. */ | |
2047 | if (width == -1) | |
b8698a0f L |
2048 | remove |
2049 | = canon_true_dependence (store_info->mem, | |
6fb5fa3c DB |
2050 | GET_MODE (store_info->mem), |
2051 | store_info->mem_addr, | |
53d9622b | 2052 | mem, mem_addr); |
b8698a0f | 2053 | |
6fb5fa3c DB |
2054 | /* If this read is just reading back something that we just |
2055 | stored, rewrite the read. */ | |
b8698a0f | 2056 | else |
6fb5fa3c DB |
2057 | { |
2058 | if (store_info->rhs | |
8dd5516b JJ |
2059 | && offset >= store_info->begin |
2060 | && offset + width <= store_info->end | |
2061 | && all_positions_needed_p (store_info, | |
2062 | offset - store_info->begin, | |
2063 | width) | |
2064 | && replace_read (store_info, i_ptr, read_info, | |
2065 | insn_info, loc, bb_info->regs_live)) | |
d7111da8 | 2066 | return; |
8dd5516b | 2067 | |
6fb5fa3c DB |
2068 | /* The bases are the same, just see if the offsets |
2069 | overlap. */ | |
b8698a0f | 2070 | if ((offset < store_info->end) |
6fb5fa3c DB |
2071 | && (offset + width > store_info->begin)) |
2072 | remove = true; | |
2073 | } | |
2074 | } | |
b8698a0f L |
2075 | |
2076 | /* else | |
6fb5fa3c DB |
2077 | The else case that is missing here is that the |
2078 | bases are constant but different. There is nothing | |
2079 | to do here because there is no overlap. */ | |
b8698a0f | 2080 | |
6fb5fa3c DB |
2081 | if (remove) |
2082 | { | |
456610d3 | 2083 | if (dump_file && (dump_flags & TDF_DETAILS)) |
6fb5fa3c DB |
2084 | dump_insn_info ("removing from active", i_ptr); |
2085 | ||
dabd47e7 | 2086 | active_local_stores_len--; |
6fb5fa3c DB |
2087 | if (last) |
2088 | last->next_local_store = i_ptr->next_local_store; | |
2089 | else | |
2090 | active_local_stores = i_ptr->next_local_store; | |
2091 | } | |
2092 | else | |
2093 | last = i_ptr; | |
2094 | i_ptr = i_ptr->next_local_store; | |
2095 | } | |
2096 | } | |
b8698a0f | 2097 | else |
6fb5fa3c DB |
2098 | { |
2099 | insn_info_t i_ptr = active_local_stores; | |
2100 | insn_info_t last = NULL; | |
456610d3 | 2101 | if (dump_file && (dump_flags & TDF_DETAILS)) |
6fb5fa3c DB |
2102 | { |
2103 | fprintf (dump_file, " processing cselib load mem:"); | |
2104 | print_inline_rtx (dump_file, mem, 0); | |
2105 | fprintf (dump_file, "\n"); | |
2106 | } | |
2107 | ||
2108 | while (i_ptr) | |
2109 | { | |
2110 | bool remove = false; | |
fd6daec9 | 2111 | store_info *store_info = i_ptr->store_rec; |
b8698a0f | 2112 | |
456610d3 | 2113 | if (dump_file && (dump_flags & TDF_DETAILS)) |
6fb5fa3c DB |
2114 | fprintf (dump_file, " processing cselib load against insn %d\n", |
2115 | INSN_UID (i_ptr->insn)); | |
2116 | ||
2117 | /* Skip the clobbers. */ | |
2118 | while (!store_info->is_set) | |
2119 | store_info = store_info->next; | |
2120 | ||
2121 | /* If this read is just reading back something that we just | |
2122 | stored, rewrite the read. */ | |
2123 | if (store_info->rhs | |
2124 | && store_info->group_id == -1 | |
2125 | && store_info->cse_base == base | |
efc3527a | 2126 | && width != -1 |
8dd5516b JJ |
2127 | && offset >= store_info->begin |
2128 | && offset + width <= store_info->end | |
2129 | && all_positions_needed_p (store_info, | |
2130 | offset - store_info->begin, width) | |
2131 | && replace_read (store_info, i_ptr, read_info, insn_info, loc, | |
2132 | bb_info->regs_live)) | |
d7111da8 | 2133 | return; |
6fb5fa3c | 2134 | |
ac6929b5 RB |
2135 | remove = canon_true_dependence (store_info->mem, |
2136 | GET_MODE (store_info->mem), | |
2137 | store_info->mem_addr, | |
2138 | mem, mem_addr); | |
b8698a0f | 2139 | |
6fb5fa3c DB |
2140 | if (remove) |
2141 | { | |
456610d3 | 2142 | if (dump_file && (dump_flags & TDF_DETAILS)) |
6fb5fa3c | 2143 | dump_insn_info ("removing from active", i_ptr); |
b8698a0f | 2144 | |
dabd47e7 | 2145 | active_local_stores_len--; |
6fb5fa3c DB |
2146 | if (last) |
2147 | last->next_local_store = i_ptr->next_local_store; | |
2148 | else | |
2149 | active_local_stores = i_ptr->next_local_store; | |
2150 | } | |
2151 | else | |
2152 | last = i_ptr; | |
2153 | i_ptr = i_ptr->next_local_store; | |
2154 | } | |
2155 | } | |
6fb5fa3c DB |
2156 | } |
2157 | ||
d7111da8 | 2158 | /* A note_uses callback in which DATA points the INSN_INFO for |
6fb5fa3c DB |
2159 | as check_mem_read_rtx. Nullify the pointer if i_m_r_m_r returns |
2160 | true for any part of *LOC. */ | |
2161 | ||
2162 | static void | |
2163 | check_mem_read_use (rtx *loc, void *data) | |
2164 | { | |
d7111da8 RS |
2165 | subrtx_ptr_iterator::array_type array; |
2166 | FOR_EACH_SUBRTX_PTR (iter, array, loc, NONCONST) | |
2167 | { | |
2168 | rtx *loc = *iter; | |
2169 | if (MEM_P (*loc)) | |
2170 | check_mem_read_rtx (loc, (bb_info_t) data); | |
2171 | } | |
6fb5fa3c DB |
2172 | } |
2173 | ||
8dd5516b JJ |
2174 | |
2175 | /* Get arguments passed to CALL_INSN. Return TRUE if successful. | |
2176 | So far it only handles arguments passed in registers. */ | |
2177 | ||
2178 | static bool | |
2179 | get_call_args (rtx call_insn, tree fn, rtx *args, int nargs) | |
2180 | { | |
d5cc9181 JR |
2181 | CUMULATIVE_ARGS args_so_far_v; |
2182 | cumulative_args_t args_so_far; | |
8dd5516b JJ |
2183 | tree arg; |
2184 | int idx; | |
2185 | ||
d5cc9181 JR |
2186 | INIT_CUMULATIVE_ARGS (args_so_far_v, TREE_TYPE (fn), NULL_RTX, 0, 3); |
2187 | args_so_far = pack_cumulative_args (&args_so_far_v); | |
8dd5516b JJ |
2188 | |
2189 | arg = TYPE_ARG_TYPES (TREE_TYPE (fn)); | |
2190 | for (idx = 0; | |
2191 | arg != void_list_node && idx < nargs; | |
2192 | arg = TREE_CHAIN (arg), idx++) | |
2193 | { | |
b4206259 | 2194 | scalar_int_mode mode; |
3c07301f | 2195 | rtx reg, link, tmp; |
b4206259 RS |
2196 | |
2197 | if (!is_int_mode (TYPE_MODE (TREE_VALUE (arg)), &mode)) | |
2198 | return false; | |
2199 | ||
d5cc9181 | 2200 | reg = targetm.calls.function_arg (args_so_far, mode, NULL_TREE, true); |
b4206259 | 2201 | if (!reg || !REG_P (reg) || GET_MODE (reg) != mode) |
8dd5516b JJ |
2202 | return false; |
2203 | ||
2204 | for (link = CALL_INSN_FUNCTION_USAGE (call_insn); | |
2205 | link; | |
2206 | link = XEXP (link, 1)) | |
2207 | if (GET_CODE (XEXP (link, 0)) == USE) | |
2208 | { | |
b4206259 | 2209 | scalar_int_mode arg_mode; |
8dd5516b JJ |
2210 | args[idx] = XEXP (XEXP (link, 0), 0); |
2211 | if (REG_P (args[idx]) | |
2212 | && REGNO (args[idx]) == REGNO (reg) | |
2213 | && (GET_MODE (args[idx]) == mode | |
b4206259 RS |
2214 | || (is_int_mode (GET_MODE (args[idx]), &arg_mode) |
2215 | && (GET_MODE_SIZE (arg_mode) <= UNITS_PER_WORD) | |
2216 | && (GET_MODE_SIZE (arg_mode) > GET_MODE_SIZE (mode))))) | |
8dd5516b JJ |
2217 | break; |
2218 | } | |
2219 | if (!link) | |
2220 | return false; | |
2221 | ||
2222 | tmp = cselib_expand_value_rtx (args[idx], scratch, 5); | |
2223 | if (GET_MODE (args[idx]) != mode) | |
2224 | { | |
2225 | if (!tmp || !CONST_INT_P (tmp)) | |
2226 | return false; | |
6d26322f | 2227 | tmp = gen_int_mode (INTVAL (tmp), mode); |
8dd5516b JJ |
2228 | } |
2229 | if (tmp) | |
2230 | args[idx] = tmp; | |
2231 | ||
d5cc9181 | 2232 | targetm.calls.function_arg_advance (args_so_far, mode, NULL_TREE, true); |
8dd5516b JJ |
2233 | } |
2234 | if (arg != void_list_node || idx != nargs) | |
2235 | return false; | |
2236 | return true; | |
2237 | } | |
2238 | ||
9e582b1d JR |
2239 | /* Return a bitmap of the fixed registers contained in IN. */ |
2240 | ||
2241 | static bitmap | |
2242 | copy_fixed_regs (const_bitmap in) | |
2243 | { | |
2244 | bitmap ret; | |
2245 | ||
2246 | ret = ALLOC_REG_SET (NULL); | |
2247 | bitmap_and (ret, in, fixed_reg_set_regset); | |
2248 | return ret; | |
2249 | } | |
8dd5516b | 2250 | |
6fb5fa3c DB |
2251 | /* Apply record_store to all candidate stores in INSN. Mark INSN |
2252 | if some part of it is not a candidate store and assigns to a | |
2253 | non-register target. */ | |
2254 | ||
2255 | static void | |
dd60a84c | 2256 | scan_insn (bb_info_t bb_info, rtx_insn *insn) |
6fb5fa3c DB |
2257 | { |
2258 | rtx body; | |
fb0b2914 | 2259 | insn_info_type *insn_info = insn_info_type_pool.allocate (); |
6fb5fa3c | 2260 | int mems_found = 0; |
da6603c6 | 2261 | memset (insn_info, 0, sizeof (struct insn_info_type)); |
6fb5fa3c | 2262 | |
456610d3 | 2263 | if (dump_file && (dump_flags & TDF_DETAILS)) |
6fb5fa3c DB |
2264 | fprintf (dump_file, "\n**scanning insn=%d\n", |
2265 | INSN_UID (insn)); | |
2266 | ||
2267 | insn_info->prev_insn = bb_info->last_insn; | |
2268 | insn_info->insn = insn; | |
2269 | bb_info->last_insn = insn_info; | |
b8698a0f | 2270 | |
b5b8b0ac AO |
2271 | if (DEBUG_INSN_P (insn)) |
2272 | { | |
2273 | insn_info->cannot_delete = true; | |
2274 | return; | |
2275 | } | |
6fb5fa3c | 2276 | |
6fb5fa3c DB |
2277 | /* Look at all of the uses in the insn. */ |
2278 | note_uses (&PATTERN (insn), check_mem_read_use, bb_info); | |
2279 | ||
2280 | if (CALL_P (insn)) | |
2281 | { | |
8dd5516b | 2282 | bool const_call; |
ee516de9 | 2283 | rtx call, sym; |
8dd5516b JJ |
2284 | tree memset_call = NULL_TREE; |
2285 | ||
6fb5fa3c | 2286 | insn_info->cannot_delete = true; |
50f0f366 | 2287 | |
6fb5fa3c | 2288 | /* Const functions cannot do anything bad i.e. read memory, |
50f0f366 | 2289 | however, they can read their parameters which may have |
8dd5516b JJ |
2290 | been pushed onto the stack. |
2291 | memset and bzero don't read memory either. */ | |
2292 | const_call = RTL_CONST_CALL_P (insn); | |
ee516de9 EB |
2293 | if (!const_call |
2294 | && (call = get_call_rtx_from (insn)) | |
2295 | && (sym = XEXP (XEXP (call, 0), 0)) | |
2296 | && GET_CODE (sym) == SYMBOL_REF | |
2297 | && SYMBOL_REF_DECL (sym) | |
2298 | && TREE_CODE (SYMBOL_REF_DECL (sym)) == FUNCTION_DECL | |
2299 | && DECL_BUILT_IN_CLASS (SYMBOL_REF_DECL (sym)) == BUILT_IN_NORMAL | |
2300 | && DECL_FUNCTION_CODE (SYMBOL_REF_DECL (sym)) == BUILT_IN_MEMSET) | |
2301 | memset_call = SYMBOL_REF_DECL (sym); | |
2302 | ||
8dd5516b | 2303 | if (const_call || memset_call) |
6fb5fa3c DB |
2304 | { |
2305 | insn_info_t i_ptr = active_local_stores; | |
2306 | insn_info_t last = NULL; | |
2307 | ||
456610d3 | 2308 | if (dump_file && (dump_flags & TDF_DETAILS)) |
8dd5516b JJ |
2309 | fprintf (dump_file, "%s call %d\n", |
2310 | const_call ? "const" : "memset", INSN_UID (insn)); | |
6fb5fa3c | 2311 | |
64520bdc | 2312 | /* See the head comment of the frame_read field. */ |
57534689 JJ |
2313 | if (reload_completed |
2314 | /* Tail calls are storing their arguments using | |
2315 | arg pointer. If it is a frame pointer on the target, | |
2316 | even before reload we need to kill frame pointer based | |
2317 | stores. */ | |
2318 | || (SIBLING_CALL_P (insn) | |
2319 | && HARD_FRAME_POINTER_IS_ARG_POINTER)) | |
64520bdc EB |
2320 | insn_info->frame_read = true; |
2321 | ||
2322 | /* Loop over the active stores and remove those which are | |
2323 | killed by the const function call. */ | |
6fb5fa3c DB |
2324 | while (i_ptr) |
2325 | { | |
64520bdc EB |
2326 | bool remove_store = false; |
2327 | ||
2328 | /* The stack pointer based stores are always killed. */ | |
50f0f366 | 2329 | if (i_ptr->stack_pointer_based) |
64520bdc EB |
2330 | remove_store = true; |
2331 | ||
2332 | /* If the frame is read, the frame related stores are killed. */ | |
2333 | else if (insn_info->frame_read) | |
2334 | { | |
fd6daec9 | 2335 | store_info *store_info = i_ptr->store_rec; |
64520bdc EB |
2336 | |
2337 | /* Skip the clobbers. */ | |
2338 | while (!store_info->is_set) | |
2339 | store_info = store_info->next; | |
2340 | ||
2341 | if (store_info->group_id >= 0 | |
9771b263 | 2342 | && rtx_group_vec[store_info->group_id]->frame_related) |
64520bdc EB |
2343 | remove_store = true; |
2344 | } | |
2345 | ||
2346 | if (remove_store) | |
6fb5fa3c | 2347 | { |
456610d3 | 2348 | if (dump_file && (dump_flags & TDF_DETAILS)) |
6fb5fa3c | 2349 | dump_insn_info ("removing from active", i_ptr); |
b8698a0f | 2350 | |
dabd47e7 | 2351 | active_local_stores_len--; |
6fb5fa3c DB |
2352 | if (last) |
2353 | last->next_local_store = i_ptr->next_local_store; | |
2354 | else | |
2355 | active_local_stores = i_ptr->next_local_store; | |
2356 | } | |
2357 | else | |
2358 | last = i_ptr; | |
64520bdc | 2359 | |
6fb5fa3c DB |
2360 | i_ptr = i_ptr->next_local_store; |
2361 | } | |
8dd5516b JJ |
2362 | |
2363 | if (memset_call) | |
2364 | { | |
2365 | rtx args[3]; | |
2366 | if (get_call_args (insn, memset_call, args, 3) | |
2367 | && CONST_INT_P (args[1]) | |
2368 | && CONST_INT_P (args[2]) | |
2369 | && INTVAL (args[2]) > 0) | |
2370 | { | |
2371 | rtx mem = gen_rtx_MEM (BLKmode, args[0]); | |
f5541398 | 2372 | set_mem_size (mem, INTVAL (args[2])); |
f7df4a84 | 2373 | body = gen_rtx_SET (mem, args[1]); |
8dd5516b | 2374 | mems_found += record_store (body, bb_info); |
456610d3 | 2375 | if (dump_file && (dump_flags & TDF_DETAILS)) |
8dd5516b JJ |
2376 | fprintf (dump_file, "handling memset as BLKmode store\n"); |
2377 | if (mems_found == 1) | |
2378 | { | |
dabd47e7 JJ |
2379 | if (active_local_stores_len++ |
2380 | >= PARAM_VALUE (PARAM_MAX_DSE_ACTIVE_LOCAL_STORES)) | |
2381 | { | |
2382 | active_local_stores_len = 1; | |
2383 | active_local_stores = NULL; | |
2384 | } | |
9e582b1d JR |
2385 | insn_info->fixed_regs_live |
2386 | = copy_fixed_regs (bb_info->regs_live); | |
8dd5516b JJ |
2387 | insn_info->next_local_store = active_local_stores; |
2388 | active_local_stores = insn_info; | |
2389 | } | |
2390 | } | |
a2ad54a0 JJ |
2391 | else |
2392 | clear_rhs_from_active_local_stores (); | |
8dd5516b | 2393 | } |
6fb5fa3c | 2394 | } |
57534689 JJ |
2395 | else if (SIBLING_CALL_P (insn) && reload_completed) |
2396 | /* Arguments for a sibling call that are pushed to memory are passed | |
2397 | using the incoming argument pointer of the current function. After | |
2398 | reload that might be (and likely is) frame pointer based. */ | |
2399 | add_wild_read (bb_info); | |
50f0f366 | 2400 | else |
d26c7090 ER |
2401 | /* Every other call, including pure functions, may read any memory |
2402 | that is not relative to the frame. */ | |
2403 | add_non_frame_wild_read (bb_info); | |
50f0f366 | 2404 | |
6fb5fa3c DB |
2405 | return; |
2406 | } | |
2407 | ||
2408 | /* Assuming that there are sets in these insns, we cannot delete | |
2409 | them. */ | |
2410 | if ((GET_CODE (PATTERN (insn)) == CLOBBER) | |
0a64eeca | 2411 | || volatile_refs_p (PATTERN (insn)) |
2da02156 | 2412 | || (!cfun->can_delete_dead_exceptions && !insn_nothrow_p (insn)) |
6fb5fa3c DB |
2413 | || (RTX_FRAME_RELATED_P (insn)) |
2414 | || find_reg_note (insn, REG_FRAME_RELATED_EXPR, NULL_RTX)) | |
2415 | insn_info->cannot_delete = true; | |
b8698a0f | 2416 | |
6fb5fa3c DB |
2417 | body = PATTERN (insn); |
2418 | if (GET_CODE (body) == PARALLEL) | |
2419 | { | |
2420 | int i; | |
2421 | for (i = 0; i < XVECLEN (body, 0); i++) | |
2422 | mems_found += record_store (XVECEXP (body, 0, i), bb_info); | |
2423 | } | |
2424 | else | |
2425 | mems_found += record_store (body, bb_info); | |
2426 | ||
456610d3 | 2427 | if (dump_file && (dump_flags & TDF_DETAILS)) |
b8698a0f | 2428 | fprintf (dump_file, "mems_found = %d, cannot_delete = %s\n", |
6fb5fa3c DB |
2429 | mems_found, insn_info->cannot_delete ? "true" : "false"); |
2430 | ||
8dd5516b JJ |
2431 | /* If we found some sets of mems, add it into the active_local_stores so |
2432 | that it can be locally deleted if found dead or used for | |
2433 | replace_read and redundant constant store elimination. Otherwise mark | |
2434 | it as cannot delete. This simplifies the processing later. */ | |
2435 | if (mems_found == 1) | |
6fb5fa3c | 2436 | { |
dabd47e7 JJ |
2437 | if (active_local_stores_len++ |
2438 | >= PARAM_VALUE (PARAM_MAX_DSE_ACTIVE_LOCAL_STORES)) | |
2439 | { | |
2440 | active_local_stores_len = 1; | |
2441 | active_local_stores = NULL; | |
2442 | } | |
9e582b1d | 2443 | insn_info->fixed_regs_live = copy_fixed_regs (bb_info->regs_live); |
6fb5fa3c DB |
2444 | insn_info->next_local_store = active_local_stores; |
2445 | active_local_stores = insn_info; | |
2446 | } | |
2447 | else | |
2448 | insn_info->cannot_delete = true; | |
2449 | } | |
2450 | ||
2451 | ||
2452 | /* Remove BASE from the set of active_local_stores. This is a | |
2453 | callback from cselib that is used to get rid of the stores in | |
2454 | active_local_stores. */ | |
2455 | ||
2456 | static void | |
2457 | remove_useless_values (cselib_val *base) | |
2458 | { | |
2459 | insn_info_t insn_info = active_local_stores; | |
2460 | insn_info_t last = NULL; | |
2461 | ||
2462 | while (insn_info) | |
2463 | { | |
fd6daec9 | 2464 | store_info *store_info = insn_info->store_rec; |
60564289 | 2465 | bool del = false; |
6fb5fa3c DB |
2466 | |
2467 | /* If ANY of the store_infos match the cselib group that is | |
2468 | being deleted, then the insn can not be deleted. */ | |
2469 | while (store_info) | |
2470 | { | |
b8698a0f | 2471 | if ((store_info->group_id == -1) |
6fb5fa3c DB |
2472 | && (store_info->cse_base == base)) |
2473 | { | |
60564289 | 2474 | del = true; |
6fb5fa3c DB |
2475 | break; |
2476 | } | |
2477 | store_info = store_info->next; | |
2478 | } | |
2479 | ||
60564289 | 2480 | if (del) |
6fb5fa3c | 2481 | { |
dabd47e7 | 2482 | active_local_stores_len--; |
6fb5fa3c DB |
2483 | if (last) |
2484 | last->next_local_store = insn_info->next_local_store; | |
2485 | else | |
2486 | active_local_stores = insn_info->next_local_store; | |
2487 | free_store_info (insn_info); | |
2488 | } | |
2489 | else | |
2490 | last = insn_info; | |
b8698a0f | 2491 | |
6fb5fa3c DB |
2492 | insn_info = insn_info->next_local_store; |
2493 | } | |
2494 | } | |
2495 | ||
2496 | ||
2497 | /* Do all of step 1. */ | |
2498 | ||
2499 | static void | |
2500 | dse_step1 (void) | |
2501 | { | |
2502 | basic_block bb; | |
3f9b14ff | 2503 | bitmap regs_live = BITMAP_ALLOC (®_obstack); |
b8698a0f | 2504 | |
457eeaae | 2505 | cselib_init (0); |
6fb5fa3c DB |
2506 | all_blocks = BITMAP_ALLOC (NULL); |
2507 | bitmap_set_bit (all_blocks, ENTRY_BLOCK); | |
2508 | bitmap_set_bit (all_blocks, EXIT_BLOCK); | |
2509 | ||
04a90bec | 2510 | FOR_ALL_BB_FN (bb, cfun) |
6fb5fa3c DB |
2511 | { |
2512 | insn_info_t ptr; | |
fb0b2914 | 2513 | bb_info_t bb_info = dse_bb_info_type_pool.allocate (); |
6fb5fa3c | 2514 | |
da6603c6 | 2515 | memset (bb_info, 0, sizeof (dse_bb_info_type)); |
6fb5fa3c | 2516 | bitmap_set_bit (all_blocks, bb->index); |
02b47899 KZ |
2517 | bb_info->regs_live = regs_live; |
2518 | ||
2519 | bitmap_copy (regs_live, DF_LR_IN (bb)); | |
2520 | df_simulate_initialize_forwards (bb, regs_live); | |
6fb5fa3c DB |
2521 | |
2522 | bb_table[bb->index] = bb_info; | |
2523 | cselib_discard_hook = remove_useless_values; | |
2524 | ||
2525 | if (bb->index >= NUM_FIXED_BLOCKS) | |
2526 | { | |
dd60a84c | 2527 | rtx_insn *insn; |
6fb5fa3c | 2528 | |
6fb5fa3c | 2529 | active_local_stores = NULL; |
dabd47e7 | 2530 | active_local_stores_len = 0; |
6fb5fa3c | 2531 | cselib_clear_table (); |
b8698a0f | 2532 | |
6fb5fa3c DB |
2533 | /* Scan the insns. */ |
2534 | FOR_BB_INSNS (bb, insn) | |
2535 | { | |
2536 | if (INSN_P (insn)) | |
2537 | scan_insn (bb_info, insn); | |
2538 | cselib_process_insn (insn); | |
02b47899 KZ |
2539 | if (INSN_P (insn)) |
2540 | df_simulate_one_insn_forwards (bb, insn, regs_live); | |
6fb5fa3c | 2541 | } |
b8698a0f | 2542 | |
6fb5fa3c DB |
2543 | /* This is something of a hack, because the global algorithm |
2544 | is supposed to take care of the case where stores go dead | |
2545 | at the end of the function. However, the global | |
2546 | algorithm must take a more conservative view of block | |
2547 | mode reads than the local alg does. So to get the case | |
2548 | where you have a store to the frame followed by a non | |
0d52bcc1 | 2549 | overlapping block more read, we look at the active local |
6fb5fa3c DB |
2550 | stores at the end of the function and delete all of the |
2551 | frame and spill based ones. */ | |
2552 | if (stores_off_frame_dead_at_return | |
2553 | && (EDGE_COUNT (bb->succs) == 0 | |
2554 | || (single_succ_p (bb) | |
fefa31b5 | 2555 | && single_succ (bb) == EXIT_BLOCK_PTR_FOR_FN (cfun) |
e3b5732b | 2556 | && ! crtl->calls_eh_return))) |
6fb5fa3c DB |
2557 | { |
2558 | insn_info_t i_ptr = active_local_stores; | |
2559 | while (i_ptr) | |
2560 | { | |
fd6daec9 | 2561 | store_info *store_info = i_ptr->store_rec; |
6fb5fa3c DB |
2562 | |
2563 | /* Skip the clobbers. */ | |
2564 | while (!store_info->is_set) | |
2565 | store_info = store_info->next; | |
ac6929b5 RB |
2566 | if (store_info->group_id >= 0) |
2567 | { | |
2568 | group_info *group = rtx_group_vec[store_info->group_id]; | |
2569 | if (group->frame_related && !i_ptr->cannot_delete) | |
2570 | delete_dead_store_insn (i_ptr); | |
2571 | } | |
6fb5fa3c DB |
2572 | |
2573 | i_ptr = i_ptr->next_local_store; | |
2574 | } | |
2575 | } | |
2576 | ||
2577 | /* Get rid of the loads that were discovered in | |
2578 | replace_read. Cselib is finished with this block. */ | |
2579 | while (deferred_change_list) | |
2580 | { | |
fd6daec9 | 2581 | deferred_change *next = deferred_change_list->next; |
6fb5fa3c DB |
2582 | |
2583 | /* There is no reason to validate this change. That was | |
2584 | done earlier. */ | |
2585 | *deferred_change_list->loc = deferred_change_list->reg; | |
fb0b2914 | 2586 | deferred_change_pool.remove (deferred_change_list); |
6fb5fa3c DB |
2587 | deferred_change_list = next; |
2588 | } | |
2589 | ||
2590 | /* Get rid of all of the cselib based store_infos in this | |
2591 | block and mark the containing insns as not being | |
2592 | deletable. */ | |
2593 | ptr = bb_info->last_insn; | |
2594 | while (ptr) | |
2595 | { | |
2596 | if (ptr->contains_cselib_groups) | |
8dd5516b | 2597 | { |
fd6daec9 | 2598 | store_info *s_info = ptr->store_rec; |
8dd5516b JJ |
2599 | while (s_info && !s_info->is_set) |
2600 | s_info = s_info->next; | |
2601 | if (s_info | |
2602 | && s_info->redundant_reason | |
2603 | && s_info->redundant_reason->insn | |
2604 | && !ptr->cannot_delete) | |
2605 | { | |
456610d3 | 2606 | if (dump_file && (dump_flags & TDF_DETAILS)) |
8dd5516b JJ |
2607 | fprintf (dump_file, "Locally deleting insn %d " |
2608 | "because insn %d stores the " | |
2609 | "same value and couldn't be " | |
2610 | "eliminated\n", | |
2611 | INSN_UID (ptr->insn), | |
2612 | INSN_UID (s_info->redundant_reason->insn)); | |
2613 | delete_dead_store_insn (ptr); | |
2614 | } | |
8dd5516b JJ |
2615 | free_store_info (ptr); |
2616 | } | |
2617 | else | |
2618 | { | |
fd6daec9 | 2619 | store_info *s_info; |
8dd5516b JJ |
2620 | |
2621 | /* Free at least positions_needed bitmaps. */ | |
2622 | for (s_info = ptr->store_rec; s_info; s_info = s_info->next) | |
2623 | if (s_info->is_large) | |
2624 | { | |
dc491a25 | 2625 | BITMAP_FREE (s_info->positions_needed.large.bmap); |
8dd5516b JJ |
2626 | s_info->is_large = false; |
2627 | } | |
2628 | } | |
6fb5fa3c DB |
2629 | ptr = ptr->prev_insn; |
2630 | } | |
2631 | ||
da6603c6 | 2632 | cse_store_info_pool.release (); |
6fb5fa3c | 2633 | } |
02b47899 | 2634 | bb_info->regs_live = NULL; |
6fb5fa3c DB |
2635 | } |
2636 | ||
02b47899 | 2637 | BITMAP_FREE (regs_live); |
6fb5fa3c | 2638 | cselib_finish (); |
c203e8a7 | 2639 | rtx_group_table->empty (); |
6fb5fa3c DB |
2640 | } |
2641 | ||
2642 | \f | |
2643 | /*---------------------------------------------------------------------------- | |
2644 | Second step. | |
2645 | ||
2646 | Assign each byte position in the stores that we are going to | |
2647 | analyze globally to a position in the bitmaps. Returns true if | |
6ed3da00 | 2648 | there are any bit positions assigned. |
6fb5fa3c DB |
2649 | ----------------------------------------------------------------------------*/ |
2650 | ||
2651 | static void | |
2652 | dse_step2_init (void) | |
2653 | { | |
2654 | unsigned int i; | |
fd6daec9 | 2655 | group_info *group; |
6fb5fa3c | 2656 | |
9771b263 | 2657 | FOR_EACH_VEC_ELT (rtx_group_vec, i, group) |
6fb5fa3c DB |
2658 | { |
2659 | /* For all non stack related bases, we only consider a store to | |
2660 | be deletable if there are two or more stores for that | |
2661 | position. This is because it takes one store to make the | |
2662 | other store redundant. However, for the stores that are | |
2663 | stack related, we consider them if there is only one store | |
2664 | for the position. We do this because the stack related | |
2665 | stores can be deleted if their is no read between them and | |
2666 | the end of the function. | |
b8698a0f | 2667 | |
6fb5fa3c DB |
2668 | To make this work in the current framework, we take the stack |
2669 | related bases add all of the bits from store1 into store2. | |
2670 | This has the effect of making the eligible even if there is | |
2671 | only one store. */ | |
2672 | ||
2673 | if (stores_off_frame_dead_at_return && group->frame_related) | |
2674 | { | |
2675 | bitmap_ior_into (group->store2_n, group->store1_n); | |
2676 | bitmap_ior_into (group->store2_p, group->store1_p); | |
456610d3 | 2677 | if (dump_file && (dump_flags & TDF_DETAILS)) |
b8698a0f | 2678 | fprintf (dump_file, "group %d is frame related ", i); |
6fb5fa3c DB |
2679 | } |
2680 | ||
2681 | group->offset_map_size_n++; | |
3f9b14ff SB |
2682 | group->offset_map_n = XOBNEWVEC (&dse_obstack, int, |
2683 | group->offset_map_size_n); | |
6fb5fa3c | 2684 | group->offset_map_size_p++; |
3f9b14ff SB |
2685 | group->offset_map_p = XOBNEWVEC (&dse_obstack, int, |
2686 | group->offset_map_size_p); | |
6fb5fa3c | 2687 | group->process_globally = false; |
456610d3 | 2688 | if (dump_file && (dump_flags & TDF_DETAILS)) |
6fb5fa3c | 2689 | { |
b8698a0f | 2690 | fprintf (dump_file, "group %d(%d+%d): ", i, |
6fb5fa3c DB |
2691 | (int)bitmap_count_bits (group->store2_n), |
2692 | (int)bitmap_count_bits (group->store2_p)); | |
2693 | bitmap_print (dump_file, group->store2_n, "n ", " "); | |
2694 | bitmap_print (dump_file, group->store2_p, "p ", "\n"); | |
2695 | } | |
2696 | } | |
2697 | } | |
2698 | ||
2699 | ||
ac6929b5 | 2700 | /* Init the offset tables. */ |
6fb5fa3c DB |
2701 | |
2702 | static bool | |
ac6929b5 | 2703 | dse_step2 (void) |
6fb5fa3c DB |
2704 | { |
2705 | unsigned int i; | |
fd6daec9 | 2706 | group_info *group; |
6fb5fa3c DB |
2707 | /* Position 0 is unused because 0 is used in the maps to mean |
2708 | unused. */ | |
2709 | current_position = 1; | |
9771b263 | 2710 | FOR_EACH_VEC_ELT (rtx_group_vec, i, group) |
6fb5fa3c DB |
2711 | { |
2712 | bitmap_iterator bi; | |
2713 | unsigned int j; | |
2714 | ||
c3284718 RS |
2715 | memset (group->offset_map_n, 0, sizeof (int) * group->offset_map_size_n); |
2716 | memset (group->offset_map_p, 0, sizeof (int) * group->offset_map_size_p); | |
6fb5fa3c DB |
2717 | bitmap_clear (group->group_kill); |
2718 | ||
2719 | EXECUTE_IF_SET_IN_BITMAP (group->store2_n, 0, j, bi) | |
2720 | { | |
2721 | bitmap_set_bit (group->group_kill, current_position); | |
d26c7090 ER |
2722 | if (bitmap_bit_p (group->escaped_n, j)) |
2723 | bitmap_set_bit (kill_on_calls, current_position); | |
6fb5fa3c DB |
2724 | group->offset_map_n[j] = current_position++; |
2725 | group->process_globally = true; | |
2726 | } | |
2727 | EXECUTE_IF_SET_IN_BITMAP (group->store2_p, 0, j, bi) | |
2728 | { | |
b8698a0f | 2729 | bitmap_set_bit (group->group_kill, current_position); |
d26c7090 ER |
2730 | if (bitmap_bit_p (group->escaped_p, j)) |
2731 | bitmap_set_bit (kill_on_calls, current_position); | |
6fb5fa3c DB |
2732 | group->offset_map_p[j] = current_position++; |
2733 | group->process_globally = true; | |
2734 | } | |
2735 | } | |
2736 | return current_position != 1; | |
2737 | } | |
2738 | ||
2739 | ||
6fb5fa3c DB |
2740 | \f |
2741 | /*---------------------------------------------------------------------------- | |
2742 | Third step. | |
b8698a0f | 2743 | |
6fb5fa3c DB |
2744 | Build the bit vectors for the transfer functions. |
2745 | ----------------------------------------------------------------------------*/ | |
2746 | ||
2747 | ||
6fb5fa3c DB |
2748 | /* Look up the bitmap index for OFFSET in GROUP_INFO. If it is not |
2749 | there, return 0. */ | |
2750 | ||
2751 | static int | |
fd6daec9 | 2752 | get_bitmap_index (group_info *group_info, HOST_WIDE_INT offset) |
6fb5fa3c DB |
2753 | { |
2754 | if (offset < 0) | |
2755 | { | |
2756 | HOST_WIDE_INT offset_p = -offset; | |
2757 | if (offset_p >= group_info->offset_map_size_n) | |
2758 | return 0; | |
2759 | return group_info->offset_map_n[offset_p]; | |
2760 | } | |
2761 | else | |
2762 | { | |
2763 | if (offset >= group_info->offset_map_size_p) | |
2764 | return 0; | |
2765 | return group_info->offset_map_p[offset]; | |
2766 | } | |
2767 | } | |
2768 | ||
2769 | ||
2770 | /* Process the STORE_INFOs into the bitmaps into GEN and KILL. KILL | |
2771 | may be NULL. */ | |
2772 | ||
b8698a0f | 2773 | static void |
ac6929b5 | 2774 | scan_stores (store_info *store_info, bitmap gen, bitmap kill) |
6fb5fa3c DB |
2775 | { |
2776 | while (store_info) | |
2777 | { | |
2778 | HOST_WIDE_INT i; | |
fd6daec9 | 2779 | group_info *group_info |
9771b263 | 2780 | = rtx_group_vec[store_info->group_id]; |
6fb5fa3c DB |
2781 | if (group_info->process_globally) |
2782 | for (i = store_info->begin; i < store_info->end; i++) | |
2783 | { | |
2784 | int index = get_bitmap_index (group_info, i); | |
2785 | if (index != 0) | |
2786 | { | |
2787 | bitmap_set_bit (gen, index); | |
2788 | if (kill) | |
2789 | bitmap_clear_bit (kill, index); | |
2790 | } | |
2791 | } | |
2792 | store_info = store_info->next; | |
2793 | } | |
2794 | } | |
2795 | ||
2796 | ||
6fb5fa3c DB |
2797 | /* Process the READ_INFOs into the bitmaps into GEN and KILL. KILL |
2798 | may be NULL. */ | |
2799 | ||
2800 | static void | |
ac6929b5 | 2801 | scan_reads (insn_info_t insn_info, bitmap gen, bitmap kill) |
6fb5fa3c DB |
2802 | { |
2803 | read_info_t read_info = insn_info->read_rec; | |
2804 | int i; | |
fd6daec9 | 2805 | group_info *group; |
6fb5fa3c | 2806 | |
64520bdc EB |
2807 | /* If this insn reads the frame, kill all the frame related stores. */ |
2808 | if (insn_info->frame_read) | |
2809 | { | |
9771b263 | 2810 | FOR_EACH_VEC_ELT (rtx_group_vec, i, group) |
64520bdc EB |
2811 | if (group->process_globally && group->frame_related) |
2812 | { | |
2813 | if (kill) | |
2814 | bitmap_ior_into (kill, group->group_kill); | |
b8698a0f | 2815 | bitmap_and_compl_into (gen, group->group_kill); |
64520bdc EB |
2816 | } |
2817 | } | |
d26c7090 ER |
2818 | if (insn_info->non_frame_wild_read) |
2819 | { | |
2820 | /* Kill all non-frame related stores. Kill all stores of variables that | |
2821 | escape. */ | |
2822 | if (kill) | |
2823 | bitmap_ior_into (kill, kill_on_calls); | |
2824 | bitmap_and_compl_into (gen, kill_on_calls); | |
9771b263 | 2825 | FOR_EACH_VEC_ELT (rtx_group_vec, i, group) |
d26c7090 ER |
2826 | if (group->process_globally && !group->frame_related) |
2827 | { | |
2828 | if (kill) | |
2829 | bitmap_ior_into (kill, group->group_kill); | |
2830 | bitmap_and_compl_into (gen, group->group_kill); | |
2831 | } | |
2832 | } | |
6fb5fa3c DB |
2833 | while (read_info) |
2834 | { | |
9771b263 | 2835 | FOR_EACH_VEC_ELT (rtx_group_vec, i, group) |
6fb5fa3c DB |
2836 | { |
2837 | if (group->process_globally) | |
2838 | { | |
2839 | if (i == read_info->group_id) | |
2840 | { | |
2841 | if (read_info->begin > read_info->end) | |
2842 | { | |
2843 | /* Begin > end for block mode reads. */ | |
2844 | if (kill) | |
2845 | bitmap_ior_into (kill, group->group_kill); | |
2846 | bitmap_and_compl_into (gen, group->group_kill); | |
2847 | } | |
2848 | else | |
2849 | { | |
2850 | /* The groups are the same, just process the | |
2851 | offsets. */ | |
2852 | HOST_WIDE_INT j; | |
2853 | for (j = read_info->begin; j < read_info->end; j++) | |
2854 | { | |
2855 | int index = get_bitmap_index (group, j); | |
2856 | if (index != 0) | |
2857 | { | |
2858 | if (kill) | |
2859 | bitmap_set_bit (kill, index); | |
2860 | bitmap_clear_bit (gen, index); | |
2861 | } | |
2862 | } | |
2863 | } | |
2864 | } | |
2865 | else | |
2866 | { | |
2867 | /* The groups are different, if the alias sets | |
2868 | conflict, clear the entire group. We only need | |
2869 | to apply this test if the read_info is a cselib | |
2870 | read. Anything with a constant base cannot alias | |
2871 | something else with a different constant | |
2872 | base. */ | |
2873 | if ((read_info->group_id < 0) | |
b8698a0f | 2874 | && canon_true_dependence (group->base_mem, |
d32f725a | 2875 | GET_MODE (group->base_mem), |
6216f94e | 2876 | group->canon_base_addr, |
53d9622b | 2877 | read_info->mem, NULL_RTX)) |
6fb5fa3c DB |
2878 | { |
2879 | if (kill) | |
2880 | bitmap_ior_into (kill, group->group_kill); | |
2881 | bitmap_and_compl_into (gen, group->group_kill); | |
2882 | } | |
2883 | } | |
2884 | } | |
2885 | } | |
b8698a0f | 2886 | |
6fb5fa3c DB |
2887 | read_info = read_info->next; |
2888 | } | |
2889 | } | |
2890 | ||
6fb5fa3c DB |
2891 | |
2892 | /* Return the insn in BB_INFO before the first wild read or if there | |
2893 | are no wild reads in the block, return the last insn. */ | |
2894 | ||
2895 | static insn_info_t | |
2896 | find_insn_before_first_wild_read (bb_info_t bb_info) | |
2897 | { | |
2898 | insn_info_t insn_info = bb_info->last_insn; | |
2899 | insn_info_t last_wild_read = NULL; | |
2900 | ||
2901 | while (insn_info) | |
2902 | { | |
2903 | if (insn_info->wild_read) | |
2904 | { | |
2905 | last_wild_read = insn_info->prev_insn; | |
2906 | /* Block starts with wild read. */ | |
2907 | if (!last_wild_read) | |
2908 | return NULL; | |
2909 | } | |
2910 | ||
2911 | insn_info = insn_info->prev_insn; | |
2912 | } | |
2913 | ||
2914 | if (last_wild_read) | |
2915 | return last_wild_read; | |
2916 | else | |
2917 | return bb_info->last_insn; | |
2918 | } | |
2919 | ||
2920 | ||
2921 | /* Scan the insns in BB_INFO starting at PTR and going to the top of | |
2922 | the block in order to build the gen and kill sets for the block. | |
2923 | We start at ptr which may be the last insn in the block or may be | |
2924 | the first insn with a wild read. In the latter case we are able to | |
2925 | skip the rest of the block because it just does not matter: | |
2926 | anything that happens is hidden by the wild read. */ | |
2927 | ||
2928 | static void | |
ac6929b5 | 2929 | dse_step3_scan (basic_block bb) |
6fb5fa3c DB |
2930 | { |
2931 | bb_info_t bb_info = bb_table[bb->index]; | |
2932 | insn_info_t insn_info; | |
2933 | ||
ac6929b5 | 2934 | insn_info = find_insn_before_first_wild_read (bb_info); |
b8698a0f | 2935 | |
6fb5fa3c DB |
2936 | /* In the spill case or in the no_spill case if there is no wild |
2937 | read in the block, we will need a kill set. */ | |
2938 | if (insn_info == bb_info->last_insn) | |
2939 | { | |
2940 | if (bb_info->kill) | |
2941 | bitmap_clear (bb_info->kill); | |
2942 | else | |
3f9b14ff | 2943 | bb_info->kill = BITMAP_ALLOC (&dse_bitmap_obstack); |
6fb5fa3c | 2944 | } |
b8698a0f | 2945 | else |
6fb5fa3c DB |
2946 | if (bb_info->kill) |
2947 | BITMAP_FREE (bb_info->kill); | |
2948 | ||
2949 | while (insn_info) | |
2950 | { | |
2951 | /* There may have been code deleted by the dce pass run before | |
2952 | this phase. */ | |
2953 | if (insn_info->insn && INSN_P (insn_info->insn)) | |
2954 | { | |
ac6929b5 RB |
2955 | scan_stores (insn_info->store_rec, bb_info->gen, bb_info->kill); |
2956 | scan_reads (insn_info, bb_info->gen, bb_info->kill); | |
b8698a0f | 2957 | } |
6fb5fa3c DB |
2958 | |
2959 | insn_info = insn_info->prev_insn; | |
2960 | } | |
2961 | } | |
2962 | ||
2963 | ||
2964 | /* Set the gen set of the exit block, and also any block with no | |
2965 | successors that does not have a wild read. */ | |
2966 | ||
2967 | static void | |
2968 | dse_step3_exit_block_scan (bb_info_t bb_info) | |
2969 | { | |
2970 | /* The gen set is all 0's for the exit block except for the | |
2971 | frame_pointer_group. */ | |
b8698a0f | 2972 | |
6fb5fa3c DB |
2973 | if (stores_off_frame_dead_at_return) |
2974 | { | |
2975 | unsigned int i; | |
fd6daec9 | 2976 | group_info *group; |
b8698a0f | 2977 | |
9771b263 | 2978 | FOR_EACH_VEC_ELT (rtx_group_vec, i, group) |
6fb5fa3c DB |
2979 | { |
2980 | if (group->process_globally && group->frame_related) | |
2981 | bitmap_ior_into (bb_info->gen, group->group_kill); | |
2982 | } | |
2983 | } | |
2984 | } | |
2985 | ||
2986 | ||
2987 | /* Find all of the blocks that are not backwards reachable from the | |
2988 | exit block or any block with no successors (BB). These are the | |
2989 | infinite loops or infinite self loops. These blocks will still | |
2990 | have their bits set in UNREACHABLE_BLOCKS. */ | |
2991 | ||
2992 | static void | |
2993 | mark_reachable_blocks (sbitmap unreachable_blocks, basic_block bb) | |
2994 | { | |
2995 | edge e; | |
2996 | edge_iterator ei; | |
2997 | ||
d7c028c0 | 2998 | if (bitmap_bit_p (unreachable_blocks, bb->index)) |
6fb5fa3c | 2999 | { |
d7c028c0 | 3000 | bitmap_clear_bit (unreachable_blocks, bb->index); |
6fb5fa3c | 3001 | FOR_EACH_EDGE (e, ei, bb->preds) |
b8698a0f | 3002 | { |
6fb5fa3c | 3003 | mark_reachable_blocks (unreachable_blocks, e->src); |
b8698a0f | 3004 | } |
6fb5fa3c DB |
3005 | } |
3006 | } | |
3007 | ||
3008 | /* Build the transfer functions for the function. */ | |
3009 | ||
3010 | static void | |
ac6929b5 | 3011 | dse_step3 () |
6fb5fa3c DB |
3012 | { |
3013 | basic_block bb; | |
6fb5fa3c DB |
3014 | sbitmap_iterator sbi; |
3015 | bitmap all_ones = NULL; | |
3016 | unsigned int i; | |
b8698a0f | 3017 | |
7ba9e72d | 3018 | auto_sbitmap unreachable_blocks (last_basic_block_for_fn (cfun)); |
f61e445a | 3019 | bitmap_ones (unreachable_blocks); |
6fb5fa3c | 3020 | |
04a90bec | 3021 | FOR_ALL_BB_FN (bb, cfun) |
6fb5fa3c DB |
3022 | { |
3023 | bb_info_t bb_info = bb_table[bb->index]; | |
3024 | if (bb_info->gen) | |
3025 | bitmap_clear (bb_info->gen); | |
3026 | else | |
3f9b14ff | 3027 | bb_info->gen = BITMAP_ALLOC (&dse_bitmap_obstack); |
6fb5fa3c DB |
3028 | |
3029 | if (bb->index == ENTRY_BLOCK) | |
3030 | ; | |
3031 | else if (bb->index == EXIT_BLOCK) | |
3032 | dse_step3_exit_block_scan (bb_info); | |
3033 | else | |
ac6929b5 | 3034 | dse_step3_scan (bb); |
6fb5fa3c DB |
3035 | if (EDGE_COUNT (bb->succs) == 0) |
3036 | mark_reachable_blocks (unreachable_blocks, bb); | |
3037 | ||
3038 | /* If this is the second time dataflow is run, delete the old | |
3039 | sets. */ | |
3040 | if (bb_info->in) | |
3041 | BITMAP_FREE (bb_info->in); | |
3042 | if (bb_info->out) | |
3043 | BITMAP_FREE (bb_info->out); | |
3044 | } | |
3045 | ||
3046 | /* For any block in an infinite loop, we must initialize the out set | |
3047 | to all ones. This could be expensive, but almost never occurs in | |
3048 | practice. However, it is common in regression tests. */ | |
d4ac4ce2 | 3049 | EXECUTE_IF_SET_IN_BITMAP (unreachable_blocks, 0, i, sbi) |
6fb5fa3c DB |
3050 | { |
3051 | if (bitmap_bit_p (all_blocks, i)) | |
3052 | { | |
3053 | bb_info_t bb_info = bb_table[i]; | |
3054 | if (!all_ones) | |
3055 | { | |
3056 | unsigned int j; | |
fd6daec9 | 3057 | group_info *group; |
6fb5fa3c | 3058 | |
3f9b14ff | 3059 | all_ones = BITMAP_ALLOC (&dse_bitmap_obstack); |
9771b263 | 3060 | FOR_EACH_VEC_ELT (rtx_group_vec, j, group) |
6fb5fa3c DB |
3061 | bitmap_ior_into (all_ones, group->group_kill); |
3062 | } | |
3063 | if (!bb_info->out) | |
3064 | { | |
3f9b14ff | 3065 | bb_info->out = BITMAP_ALLOC (&dse_bitmap_obstack); |
6fb5fa3c DB |
3066 | bitmap_copy (bb_info->out, all_ones); |
3067 | } | |
3068 | } | |
3069 | } | |
3070 | ||
3071 | if (all_ones) | |
3072 | BITMAP_FREE (all_ones); | |
6fb5fa3c DB |
3073 | } |
3074 | ||
3075 | ||
3076 | \f | |
3077 | /*---------------------------------------------------------------------------- | |
3078 | Fourth step. | |
3079 | ||
3080 | Solve the bitvector equations. | |
3081 | ----------------------------------------------------------------------------*/ | |
3082 | ||
3083 | ||
3084 | /* Confluence function for blocks with no successors. Create an out | |
3085 | set from the gen set of the exit block. This block logically has | |
3086 | the exit block as a successor. */ | |
3087 | ||
3088 | ||
3089 | ||
3090 | static void | |
3091 | dse_confluence_0 (basic_block bb) | |
3092 | { | |
3093 | bb_info_t bb_info = bb_table[bb->index]; | |
3094 | ||
3095 | if (bb->index == EXIT_BLOCK) | |
3096 | return; | |
3097 | ||
3098 | if (!bb_info->out) | |
3099 | { | |
3f9b14ff | 3100 | bb_info->out = BITMAP_ALLOC (&dse_bitmap_obstack); |
6fb5fa3c DB |
3101 | bitmap_copy (bb_info->out, bb_table[EXIT_BLOCK]->gen); |
3102 | } | |
3103 | } | |
3104 | ||
3105 | /* Propagate the information from the in set of the dest of E to the | |
3106 | out set of the src of E. If the various in or out sets are not | |
3107 | there, that means they are all ones. */ | |
3108 | ||
1a0f3fa1 | 3109 | static bool |
6fb5fa3c DB |
3110 | dse_confluence_n (edge e) |
3111 | { | |
3112 | bb_info_t src_info = bb_table[e->src->index]; | |
3113 | bb_info_t dest_info = bb_table[e->dest->index]; | |
3114 | ||
3115 | if (dest_info->in) | |
3116 | { | |
3117 | if (src_info->out) | |
3118 | bitmap_and_into (src_info->out, dest_info->in); | |
3119 | else | |
3120 | { | |
3f9b14ff | 3121 | src_info->out = BITMAP_ALLOC (&dse_bitmap_obstack); |
6fb5fa3c DB |
3122 | bitmap_copy (src_info->out, dest_info->in); |
3123 | } | |
3124 | } | |
1a0f3fa1 | 3125 | return true; |
6fb5fa3c DB |
3126 | } |
3127 | ||
3128 | ||
3129 | /* Propagate the info from the out to the in set of BB_INDEX's basic | |
b8698a0f | 3130 | block. There are three cases: |
6fb5fa3c DB |
3131 | |
3132 | 1) The block has no kill set. In this case the kill set is all | |
3133 | ones. It does not matter what the out set of the block is, none of | |
3134 | the info can reach the top. The only thing that reaches the top is | |
3135 | the gen set and we just copy the set. | |
3136 | ||
3137 | 2) There is a kill set but no out set and bb has successors. In | |
3138 | this case we just return. Eventually an out set will be created and | |
3139 | it is better to wait than to create a set of ones. | |
3140 | ||
3141 | 3) There is both a kill and out set. We apply the obvious transfer | |
3142 | function. | |
3143 | */ | |
3144 | ||
3145 | static bool | |
3146 | dse_transfer_function (int bb_index) | |
3147 | { | |
3148 | bb_info_t bb_info = bb_table[bb_index]; | |
3149 | ||
3150 | if (bb_info->kill) | |
3151 | { | |
3152 | if (bb_info->out) | |
3153 | { | |
3154 | /* Case 3 above. */ | |
3155 | if (bb_info->in) | |
b8698a0f | 3156 | return bitmap_ior_and_compl (bb_info->in, bb_info->gen, |
6fb5fa3c DB |
3157 | bb_info->out, bb_info->kill); |
3158 | else | |
3159 | { | |
3f9b14ff | 3160 | bb_info->in = BITMAP_ALLOC (&dse_bitmap_obstack); |
b8698a0f | 3161 | bitmap_ior_and_compl (bb_info->in, bb_info->gen, |
6fb5fa3c DB |
3162 | bb_info->out, bb_info->kill); |
3163 | return true; | |
3164 | } | |
3165 | } | |
3166 | else | |
3167 | /* Case 2 above. */ | |
3168 | return false; | |
3169 | } | |
3170 | else | |
3171 | { | |
3172 | /* Case 1 above. If there is already an in set, nothing | |
3173 | happens. */ | |
3174 | if (bb_info->in) | |
3175 | return false; | |
3176 | else | |
3177 | { | |
3f9b14ff | 3178 | bb_info->in = BITMAP_ALLOC (&dse_bitmap_obstack); |
6fb5fa3c DB |
3179 | bitmap_copy (bb_info->in, bb_info->gen); |
3180 | return true; | |
3181 | } | |
3182 | } | |
3183 | } | |
3184 | ||
3185 | /* Solve the dataflow equations. */ | |
3186 | ||
3187 | static void | |
3188 | dse_step4 (void) | |
3189 | { | |
b8698a0f L |
3190 | df_simple_dataflow (DF_BACKWARD, NULL, dse_confluence_0, |
3191 | dse_confluence_n, dse_transfer_function, | |
3192 | all_blocks, df_get_postorder (DF_BACKWARD), | |
6fb5fa3c | 3193 | df_get_n_blocks (DF_BACKWARD)); |
456610d3 | 3194 | if (dump_file && (dump_flags & TDF_DETAILS)) |
6fb5fa3c DB |
3195 | { |
3196 | basic_block bb; | |
3197 | ||
3198 | fprintf (dump_file, "\n\n*** Global dataflow info after analysis.\n"); | |
04a90bec | 3199 | FOR_ALL_BB_FN (bb, cfun) |
6fb5fa3c DB |
3200 | { |
3201 | bb_info_t bb_info = bb_table[bb->index]; | |
3202 | ||
3203 | df_print_bb_index (bb, dump_file); | |
3204 | if (bb_info->in) | |
3205 | bitmap_print (dump_file, bb_info->in, " in: ", "\n"); | |
3206 | else | |
3207 | fprintf (dump_file, " in: *MISSING*\n"); | |
3208 | if (bb_info->gen) | |
3209 | bitmap_print (dump_file, bb_info->gen, " gen: ", "\n"); | |
3210 | else | |
3211 | fprintf (dump_file, " gen: *MISSING*\n"); | |
3212 | if (bb_info->kill) | |
3213 | bitmap_print (dump_file, bb_info->kill, " kill: ", "\n"); | |
3214 | else | |
3215 | fprintf (dump_file, " kill: *MISSING*\n"); | |
3216 | if (bb_info->out) | |
3217 | bitmap_print (dump_file, bb_info->out, " out: ", "\n"); | |
3218 | else | |
3219 | fprintf (dump_file, " out: *MISSING*\n\n"); | |
3220 | } | |
3221 | } | |
3222 | } | |
3223 | ||
3224 | ||
3225 | \f | |
3226 | /*---------------------------------------------------------------------------- | |
3227 | Fifth step. | |
3228 | ||
0d52bcc1 | 3229 | Delete the stores that can only be deleted using the global information. |
6fb5fa3c DB |
3230 | ----------------------------------------------------------------------------*/ |
3231 | ||
3232 | ||
3233 | static void | |
ac6929b5 | 3234 | dse_step5 (void) |
6fb5fa3c DB |
3235 | { |
3236 | basic_block bb; | |
11cd3bed | 3237 | FOR_EACH_BB_FN (bb, cfun) |
6fb5fa3c DB |
3238 | { |
3239 | bb_info_t bb_info = bb_table[bb->index]; | |
3240 | insn_info_t insn_info = bb_info->last_insn; | |
3241 | bitmap v = bb_info->out; | |
3242 | ||
3243 | while (insn_info) | |
3244 | { | |
3245 | bool deleted = false; | |
3246 | if (dump_file && insn_info->insn) | |
3247 | { | |
3248 | fprintf (dump_file, "starting to process insn %d\n", | |
3249 | INSN_UID (insn_info->insn)); | |
3250 | bitmap_print (dump_file, v, " v: ", "\n"); | |
3251 | } | |
3252 | ||
3253 | /* There may have been code deleted by the dce pass run before | |
3254 | this phase. */ | |
b8698a0f | 3255 | if (insn_info->insn |
6fb5fa3c DB |
3256 | && INSN_P (insn_info->insn) |
3257 | && (!insn_info->cannot_delete) | |
3258 | && (!bitmap_empty_p (v))) | |
3259 | { | |
fd6daec9 | 3260 | store_info *store_info = insn_info->store_rec; |
6fb5fa3c DB |
3261 | |
3262 | /* Try to delete the current insn. */ | |
3263 | deleted = true; | |
b8698a0f | 3264 | |
6fb5fa3c DB |
3265 | /* Skip the clobbers. */ |
3266 | while (!store_info->is_set) | |
3267 | store_info = store_info->next; | |
3268 | ||
ac6929b5 RB |
3269 | HOST_WIDE_INT i; |
3270 | group_info *group_info = rtx_group_vec[store_info->group_id]; | |
3271 | ||
3272 | for (i = store_info->begin; i < store_info->end; i++) | |
6fb5fa3c | 3273 | { |
ac6929b5 | 3274 | int index = get_bitmap_index (group_info, i); |
b8698a0f | 3275 | |
ac6929b5 RB |
3276 | if (dump_file && (dump_flags & TDF_DETAILS)) |
3277 | fprintf (dump_file, "i = %d, index = %d\n", (int)i, index); | |
3278 | if (index == 0 || !bitmap_bit_p (v, index)) | |
6fb5fa3c | 3279 | { |
456610d3 | 3280 | if (dump_file && (dump_flags & TDF_DETAILS)) |
ac6929b5 RB |
3281 | fprintf (dump_file, "failing at i = %d\n", (int)i); |
3282 | deleted = false; | |
3283 | break; | |
6fb5fa3c DB |
3284 | } |
3285 | } | |
3286 | if (deleted) | |
3287 | { | |
9e582b1d JR |
3288 | if (dbg_cnt (dse) |
3289 | && check_for_inc_dec_1 (insn_info)) | |
6fb5fa3c | 3290 | { |
6fb5fa3c DB |
3291 | delete_insn (insn_info->insn); |
3292 | insn_info->insn = NULL; | |
3293 | globally_deleted++; | |
3294 | } | |
3295 | } | |
3296 | } | |
3297 | /* We do want to process the local info if the insn was | |
6ed3da00 | 3298 | deleted. For instance, if the insn did a wild read, we |
6fb5fa3c | 3299 | no longer need to trash the info. */ |
b8698a0f | 3300 | if (insn_info->insn |
6fb5fa3c DB |
3301 | && INSN_P (insn_info->insn) |
3302 | && (!deleted)) | |
3303 | { | |
ac6929b5 | 3304 | scan_stores (insn_info->store_rec, v, NULL); |
6fb5fa3c DB |
3305 | if (insn_info->wild_read) |
3306 | { | |
456610d3 | 3307 | if (dump_file && (dump_flags & TDF_DETAILS)) |
6fb5fa3c DB |
3308 | fprintf (dump_file, "wild read\n"); |
3309 | bitmap_clear (v); | |
3310 | } | |
d26c7090 | 3311 | else if (insn_info->read_rec |
a8404b9a JJ |
3312 | || insn_info->non_frame_wild_read |
3313 | || insn_info->frame_read) | |
6fb5fa3c | 3314 | { |
a8404b9a JJ |
3315 | if (dump_file && (dump_flags & TDF_DETAILS)) |
3316 | { | |
3317 | if (!insn_info->non_frame_wild_read | |
3318 | && !insn_info->frame_read) | |
3319 | fprintf (dump_file, "regular read\n"); | |
3320 | if (insn_info->non_frame_wild_read) | |
3321 | fprintf (dump_file, "non-frame wild read\n"); | |
3322 | if (insn_info->frame_read) | |
3323 | fprintf (dump_file, "frame read\n"); | |
3324 | } | |
ac6929b5 | 3325 | scan_reads (insn_info, v, NULL); |
6fb5fa3c DB |
3326 | } |
3327 | } | |
b8698a0f | 3328 | |
6fb5fa3c DB |
3329 | insn_info = insn_info->prev_insn; |
3330 | } | |
3331 | } | |
3332 | } | |
3333 | ||
3334 | ||
6fb5fa3c DB |
3335 | \f |
3336 | /*---------------------------------------------------------------------------- | |
3337 | Sixth step. | |
3338 | ||
8dd5516b JJ |
3339 | Delete stores made redundant by earlier stores (which store the same |
3340 | value) that couldn't be eliminated. | |
3341 | ----------------------------------------------------------------------------*/ | |
3342 | ||
3343 | static void | |
3344 | dse_step6 (void) | |
3345 | { | |
3346 | basic_block bb; | |
3347 | ||
04a90bec | 3348 | FOR_ALL_BB_FN (bb, cfun) |
8dd5516b JJ |
3349 | { |
3350 | bb_info_t bb_info = bb_table[bb->index]; | |
3351 | insn_info_t insn_info = bb_info->last_insn; | |
3352 | ||
3353 | while (insn_info) | |
3354 | { | |
3355 | /* There may have been code deleted by the dce pass run before | |
3356 | this phase. */ | |
3357 | if (insn_info->insn | |
3358 | && INSN_P (insn_info->insn) | |
3359 | && !insn_info->cannot_delete) | |
3360 | { | |
fd6daec9 | 3361 | store_info *s_info = insn_info->store_rec; |
8dd5516b JJ |
3362 | |
3363 | while (s_info && !s_info->is_set) | |
3364 | s_info = s_info->next; | |
3365 | if (s_info | |
3366 | && s_info->redundant_reason | |
3367 | && s_info->redundant_reason->insn | |
3368 | && INSN_P (s_info->redundant_reason->insn)) | |
3369 | { | |
eb92d49a | 3370 | rtx_insn *rinsn = s_info->redundant_reason->insn; |
456610d3 | 3371 | if (dump_file && (dump_flags & TDF_DETAILS)) |
8dd5516b JJ |
3372 | fprintf (dump_file, "Locally deleting insn %d " |
3373 | "because insn %d stores the " | |
3374 | "same value and couldn't be " | |
3375 | "eliminated\n", | |
3376 | INSN_UID (insn_info->insn), | |
3377 | INSN_UID (rinsn)); | |
3378 | delete_dead_store_insn (insn_info); | |
3379 | } | |
3380 | } | |
3381 | insn_info = insn_info->prev_insn; | |
3382 | } | |
3383 | } | |
3384 | } | |
3385 | \f | |
3386 | /*---------------------------------------------------------------------------- | |
3387 | Seventh step. | |
3388 | ||
b8698a0f | 3389 | Destroy everything left standing. |
6fb5fa3c DB |
3390 | ----------------------------------------------------------------------------*/ |
3391 | ||
b8698a0f | 3392 | static void |
3f9b14ff | 3393 | dse_step7 (void) |
6fb5fa3c | 3394 | { |
3f9b14ff SB |
3395 | bitmap_obstack_release (&dse_bitmap_obstack); |
3396 | obstack_free (&dse_obstack, NULL); | |
370f38e8 | 3397 | |
6fb5fa3c DB |
3398 | end_alias_analysis (); |
3399 | free (bb_table); | |
c203e8a7 TS |
3400 | delete rtx_group_table; |
3401 | rtx_group_table = NULL; | |
9771b263 | 3402 | rtx_group_vec.release (); |
6fb5fa3c DB |
3403 | BITMAP_FREE (all_blocks); |
3404 | BITMAP_FREE (scratch); | |
3405 | ||
da6603c6 | 3406 | rtx_store_info_pool.release (); |
fb0b2914 ML |
3407 | read_info_type_pool.release (); |
3408 | insn_info_type_pool.release (); | |
3409 | dse_bb_info_type_pool.release (); | |
3410 | group_info_pool.release (); | |
3411 | deferred_change_pool.release (); | |
6fb5fa3c DB |
3412 | } |
3413 | ||
3414 | ||
6fb5fa3c DB |
3415 | /* ------------------------------------------------------------------------- |
3416 | DSE | |
3417 | ------------------------------------------------------------------------- */ | |
3418 | ||
3419 | /* Callback for running pass_rtl_dse. */ | |
3420 | ||
3421 | static unsigned int | |
3422 | rest_of_handle_dse (void) | |
3423 | { | |
6fb5fa3c DB |
3424 | df_set_flags (DF_DEFER_INSN_RESCAN); |
3425 | ||
02b47899 KZ |
3426 | /* Need the notes since we must track live hardregs in the forwards |
3427 | direction. */ | |
3428 | df_note_add_problem (); | |
3429 | df_analyze (); | |
3430 | ||
6fb5fa3c DB |
3431 | dse_step0 (); |
3432 | dse_step1 (); | |
3433 | dse_step2_init (); | |
ac6929b5 | 3434 | if (dse_step2 ()) |
6fb5fa3c DB |
3435 | { |
3436 | df_set_flags (DF_LR_RUN_DCE); | |
3437 | df_analyze (); | |
456610d3 | 3438 | if (dump_file && (dump_flags & TDF_DETAILS)) |
6fb5fa3c | 3439 | fprintf (dump_file, "doing global processing\n"); |
ac6929b5 | 3440 | dse_step3 (); |
6fb5fa3c | 3441 | dse_step4 (); |
ac6929b5 | 3442 | dse_step5 (); |
6fb5fa3c DB |
3443 | } |
3444 | ||
8dd5516b | 3445 | dse_step6 (); |
3f9b14ff | 3446 | dse_step7 (); |
6fb5fa3c DB |
3447 | |
3448 | if (dump_file) | |
ac6929b5 RB |
3449 | fprintf (dump_file, "dse: local deletions = %d, global deletions = %d\n", |
3450 | locally_deleted, globally_deleted); | |
6c5ed3f1 JJ |
3451 | |
3452 | /* DSE can eliminate potentially-trapping MEMs. | |
3453 | Remove any EH edges associated with them. */ | |
3454 | if ((locally_deleted || globally_deleted) | |
3455 | && cfun->can_throw_non_call_exceptions | |
3456 | && purge_all_dead_edges ()) | |
3457 | cleanup_cfg (0); | |
3458 | ||
6fb5fa3c DB |
3459 | return 0; |
3460 | } | |
3461 | ||
17795822 TS |
3462 | namespace { |
3463 | ||
3464 | const pass_data pass_data_rtl_dse1 = | |
27a4cd48 DM |
3465 | { |
3466 | RTL_PASS, /* type */ | |
3467 | "dse1", /* name */ | |
3468 | OPTGROUP_NONE, /* optinfo_flags */ | |
27a4cd48 DM |
3469 | TV_DSE1, /* tv_id */ |
3470 | 0, /* properties_required */ | |
3471 | 0, /* properties_provided */ | |
3472 | 0, /* properties_destroyed */ | |
3473 | 0, /* todo_flags_start */ | |
3bea341f | 3474 | TODO_df_finish, /* todo_flags_finish */ |
6fb5fa3c DB |
3475 | }; |
3476 | ||
17795822 | 3477 | class pass_rtl_dse1 : public rtl_opt_pass |
27a4cd48 DM |
3478 | { |
3479 | public: | |
c3284718 RS |
3480 | pass_rtl_dse1 (gcc::context *ctxt) |
3481 | : rtl_opt_pass (pass_data_rtl_dse1, ctxt) | |
27a4cd48 DM |
3482 | {} |
3483 | ||
3484 | /* opt_pass methods: */ | |
1a3d085c TS |
3485 | virtual bool gate (function *) |
3486 | { | |
3487 | return optimize > 0 && flag_dse && dbg_cnt (dse1); | |
3488 | } | |
3489 | ||
be55bfe6 | 3490 | virtual unsigned int execute (function *) { return rest_of_handle_dse (); } |
27a4cd48 DM |
3491 | |
3492 | }; // class pass_rtl_dse1 | |
3493 | ||
17795822 TS |
3494 | } // anon namespace |
3495 | ||
27a4cd48 DM |
3496 | rtl_opt_pass * |
3497 | make_pass_rtl_dse1 (gcc::context *ctxt) | |
3498 | { | |
3499 | return new pass_rtl_dse1 (ctxt); | |
3500 | } | |
3501 | ||
17795822 TS |
3502 | namespace { |
3503 | ||
3504 | const pass_data pass_data_rtl_dse2 = | |
27a4cd48 DM |
3505 | { |
3506 | RTL_PASS, /* type */ | |
3507 | "dse2", /* name */ | |
3508 | OPTGROUP_NONE, /* optinfo_flags */ | |
27a4cd48 DM |
3509 | TV_DSE2, /* tv_id */ |
3510 | 0, /* properties_required */ | |
3511 | 0, /* properties_provided */ | |
3512 | 0, /* properties_destroyed */ | |
3513 | 0, /* todo_flags_start */ | |
3bea341f | 3514 | TODO_df_finish, /* todo_flags_finish */ |
6fb5fa3c | 3515 | }; |
27a4cd48 | 3516 | |
17795822 | 3517 | class pass_rtl_dse2 : public rtl_opt_pass |
27a4cd48 DM |
3518 | { |
3519 | public: | |
c3284718 RS |
3520 | pass_rtl_dse2 (gcc::context *ctxt) |
3521 | : rtl_opt_pass (pass_data_rtl_dse2, ctxt) | |
27a4cd48 DM |
3522 | {} |
3523 | ||
3524 | /* opt_pass methods: */ | |
1a3d085c TS |
3525 | virtual bool gate (function *) |
3526 | { | |
3527 | return optimize > 0 && flag_dse && dbg_cnt (dse2); | |
3528 | } | |
3529 | ||
be55bfe6 | 3530 | virtual unsigned int execute (function *) { return rest_of_handle_dse (); } |
27a4cd48 DM |
3531 | |
3532 | }; // class pass_rtl_dse2 | |
3533 | ||
17795822 TS |
3534 | } // anon namespace |
3535 | ||
27a4cd48 DM |
3536 | rtl_opt_pass * |
3537 | make_pass_rtl_dse2 (gcc::context *ctxt) | |
3538 | { | |
3539 | return new pass_rtl_dse2 (ctxt); | |
3540 | } |