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e011eba9 | 1 | /* Allocation for dataflow support routines. |
3072d30e | 2 | Copyright (C) 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007 |
e011eba9 | 3 | Free Software Foundation, Inc. |
4 | Originally contributed by Michael P. Hayes | |
5 | (m.hayes@elec.canterbury.ac.nz, mhayes@redhat.com) | |
6 | Major rewrite contributed by Danny Berlin (dberlin@dberlin.org) | |
7 | and Kenneth Zadeck (zadeck@naturalbridge.com). | |
8 | ||
9 | This file is part of GCC. | |
10 | ||
11 | GCC is free software; you can redistribute it and/or modify it under | |
12 | the terms of the GNU General Public License as published by the Free | |
8c4c00c1 | 13 | Software Foundation; either version 3, or (at your option) any later |
e011eba9 | 14 | version. |
15 | ||
16 | GCC is distributed in the hope that it will be useful, but WITHOUT ANY | |
17 | WARRANTY; without even the implied warranty of MERCHANTABILITY or | |
18 | FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License | |
19 | for more details. | |
20 | ||
21 | You should have received a copy of the GNU General Public License | |
8c4c00c1 | 22 | along with GCC; see the file COPYING3. If not see |
23 | <http://www.gnu.org/licenses/>. */ | |
e011eba9 | 24 | |
25 | /* | |
26 | OVERVIEW: | |
27 | ||
28 | The files in this collection (df*.c,df.h) provide a general framework | |
29 | for solving dataflow problems. The global dataflow is performed using | |
30 | a good implementation of iterative dataflow analysis. | |
31 | ||
32 | The file df-problems.c provides problem instance for the most common | |
33 | dataflow problems: reaching defs, upward exposed uses, live variables, | |
34 | uninitialized variables, def-use chains, and use-def chains. However, | |
35 | the interface allows other dataflow problems to be defined as well. | |
36 | ||
3072d30e | 37 | Dataflow analysis is available in most of the rtl backend (the parts |
38 | between pass_df_initialize and pass_df_finish). It is quite likely | |
39 | that these boundaries will be expanded in the future. The only | |
40 | requirement is that there be a correct control flow graph. | |
e011eba9 | 41 | |
3072d30e | 42 | There are three variations of the live variable problem that are |
43 | available whenever dataflow is available. The LR problem finds the | |
44 | areas that can reach a use of a variable, the UR problems finds the | |
45 | areas tha can be reached from a definition of a variable. The LIVE | |
46 | problem finds the intersection of these two areas. | |
e011eba9 | 47 | |
3072d30e | 48 | There are several optional problems. These can be enabled when they |
49 | are needed and disabled when they are not needed. | |
e011eba9 | 50 | |
3072d30e | 51 | Dataflow problems are generally solved in three layers. The bottom |
52 | layer is called scanning where a data structure is built for each rtl | |
53 | insn that describes the set of defs and uses of that insn. Scanning | |
54 | is generally kept up to date, i.e. as the insns changes, the scanned | |
55 | version of that insn changes also. There are various mechanisms for | |
56 | making this happen and are described in the INCREMENTAL SCANNING | |
57 | section. | |
e011eba9 | 58 | |
3072d30e | 59 | In the middle layer, basic blocks are scanned to produce transfer |
60 | functions which describe the effects of that block on the a global | |
61 | dataflow solution. The transfer functions are only rebuilt if the | |
62 | some instruction within the block has changed. | |
e011eba9 | 63 | |
3072d30e | 64 | The top layer is the dataflow solution itself. The dataflow solution |
bef304b8 | 65 | is computed by using an efficient iterative solver and the transfer |
3072d30e | 66 | functions. The dataflow solution must be recomputed whenever the |
67 | control changes or if one of the transfer function changes. | |
e011eba9 | 68 | |
69 | ||
3072d30e | 70 | USAGE: |
e011eba9 | 71 | |
3072d30e | 72 | Here is an example of using the dataflow routines. |
e011eba9 | 73 | |
84da8954 | 74 | df_[chain,live,note,rd]_add_problem (flags); |
e011eba9 | 75 | |
3072d30e | 76 | df_set_blocks (blocks); |
e011eba9 | 77 | |
3072d30e | 78 | df_analyze (); |
e011eba9 | 79 | |
3072d30e | 80 | df_dump (stderr); |
e011eba9 | 81 | |
314966f4 | 82 | df_finish_pass (false); |
e011eba9 | 83 | |
84da8954 | 84 | DF_[chain,live,note,rd]_ADD_PROBLEM adds a problem, defined by an |
3072d30e | 85 | instance to struct df_problem, to the set of problems solved in this |
86 | instance of df. All calls to add a problem for a given instance of df | |
87 | must occur before the first call to DF_ANALYZE. | |
e011eba9 | 88 | |
89 | Problems can be dependent on other problems. For instance, solving | |
ed7bb01a | 90 | def-use or use-def chains is dependent on solving reaching |
334ec2d8 | 91 | definitions. As long as these dependencies are listed in the problem |
e011eba9 | 92 | definition, the order of adding the problems is not material. |
93 | Otherwise, the problems will be solved in the order of calls to | |
94 | df_add_problem. Note that it is not necessary to have a problem. In | |
95 | that case, df will just be used to do the scanning. | |
96 | ||
97 | ||
98 | ||
99 | DF_SET_BLOCKS is an optional call used to define a region of the | |
100 | function on which the analysis will be performed. The normal case is | |
101 | to analyze the entire function and no call to df_set_blocks is made. | |
3072d30e | 102 | DF_SET_BLOCKS only effects the blocks that are effected when computing |
103 | the transfer functions and final solution. The insn level information | |
104 | is always kept up to date. | |
e011eba9 | 105 | |
106 | When a subset is given, the analysis behaves as if the function only | |
107 | contains those blocks and any edges that occur directly between the | |
108 | blocks in the set. Care should be taken to call df_set_blocks right | |
334ec2d8 | 109 | before the call to analyze in order to eliminate the possibility that |
e011eba9 | 110 | optimizations that reorder blocks invalidate the bitvector. |
111 | ||
3072d30e | 112 | DF_ANALYZE causes all of the defined problems to be (re)solved. When |
113 | DF_ANALYZE is completes, the IN and OUT sets for each basic block | |
114 | contain the computer information. The DF_*_BB_INFO macros can be used | |
a3de79f9 | 115 | to access these bitvectors. All deferred rescannings are down before |
bef304b8 | 116 | the transfer functions are recomputed. |
e011eba9 | 117 | |
118 | DF_DUMP can then be called to dump the information produce to some | |
3072d30e | 119 | file. This calls DF_DUMP_START, to print the information that is not |
120 | basic block specific, and then calls DF_DUMP_TOP and DF_DUMP_BOTTOM | |
121 | for each block to print the basic specific information. These parts | |
122 | can all be called separately as part of a larger dump function. | |
123 | ||
124 | ||
125 | DF_FINISH_PASS causes df_remove_problem to be called on all of the | |
126 | optional problems. It also causes any insns whose scanning has been | |
a3de79f9 | 127 | deferred to be rescanned as well as clears all of the changeable flags. |
3072d30e | 128 | Setting the pass manager TODO_df_finish flag causes this function to |
129 | be run. However, the pass manager will call df_finish_pass AFTER the | |
130 | pass dumping has been done, so if you want to see the results of the | |
131 | optional problems in the pass dumps, use the TODO flag rather than | |
132 | calling the function yourself. | |
133 | ||
134 | INCREMENTAL SCANNING | |
135 | ||
136 | There are four ways of doing the incremental scanning: | |
137 | ||
138 | 1) Immediate rescanning - Calls to df_insn_rescan, df_notes_rescan, | |
139 | df_bb_delete, df_insn_change_bb have been added to most of | |
140 | the low level service functions that maintain the cfg and change | |
141 | rtl. Calling and of these routines many cause some number of insns | |
142 | to be rescanned. | |
143 | ||
144 | For most modern rtl passes, this is certainly the easiest way to | |
145 | manage rescanning the insns. This technique also has the advantage | |
146 | that the scanning information is always correct and can be relied | |
4a7e4fcc | 147 | upon even after changes have been made to the instructions. This |
3072d30e | 148 | technique is contra indicated in several cases: |
149 | ||
150 | a) If def-use chains OR use-def chains (but not both) are built, | |
151 | using this is SIMPLY WRONG. The problem is that when a ref is | |
152 | deleted that is the target of an edge, there is not enough | |
153 | information to efficiently find the source of the edge and | |
154 | delete the edge. This leaves a dangling reference that may | |
155 | cause problems. | |
156 | ||
157 | b) If def-use chains AND use-def chains are built, this may | |
158 | produce unexpected results. The problem is that the incremental | |
159 | scanning of an insn does not know how to repair the chains that | |
160 | point into an insn when the insn changes. So the incremental | |
161 | scanning just deletes the chains that enter and exit the insn | |
162 | being changed. The dangling reference issue in (a) is not a | |
163 | problem here, but if the pass is depending on the chains being | |
164 | maintained after insns have been modified, this technique will | |
165 | not do the correct thing. | |
166 | ||
167 | c) If the pass modifies insns several times, this incremental | |
168 | updating may be expensive. | |
169 | ||
170 | d) If the pass modifies all of the insns, as does register | |
171 | allocation, it is simply better to rescan the entire function. | |
172 | ||
173 | e) If the pass uses either non-standard or ancient techniques to | |
174 | modify insns, automatic detection of the insns that need to be | |
175 | rescanned may be impractical. Cse and regrename fall into this | |
176 | category. | |
177 | ||
bef304b8 | 178 | 2) Deferred rescanning - Calls to df_insn_rescan, df_notes_rescan, and |
3072d30e | 179 | df_insn_delete do not immediately change the insn but instead make |
180 | a note that the insn needs to be rescanned. The next call to | |
181 | df_analyze, df_finish_pass, or df_process_deferred_rescans will | |
182 | cause all of the pending rescans to be processed. | |
183 | ||
184 | This is the technique of choice if either 1a, 1b, or 1c are issues | |
185 | in the pass. In the case of 1a or 1b, a call to df_remove_problem | |
186 | (df_chain) should be made before the next call to df_analyze or | |
187 | df_process_deferred_rescans. | |
188 | ||
189 | To enable this mode, call df_set_flags (DF_DEFER_INSN_RESCAN). | |
190 | (This mode can be cleared by calling df_clear_flags | |
a3de79f9 | 191 | (DF_DEFER_INSN_RESCAN) but this does not cause the deferred insns to |
3072d30e | 192 | be rescanned. |
193 | ||
194 | 3) Total rescanning - In this mode the rescanning is disabled. | |
195 | However, the df information associated with deleted insn is delete | |
196 | at the time the insn is deleted. At the end of the pass, a call | |
197 | must be made to df_insn_rescan_all. This method is used by the | |
198 | register allocator since it generally changes each insn multiple | |
199 | times (once for each ref) and does not need to make use of the | |
200 | updated scanning information. | |
201 | ||
202 | It is also currently used by two older passes (cse, and regrename) | |
203 | which change insns in hard to track ways. It is hoped that this | |
204 | will be fixed soon since this it is expensive to rescan all of the | |
205 | insns when only a small number of them have really changed. | |
206 | ||
207 | 4) Do it yourself - In this mechanism, the pass updates the insns | |
6dfdc153 | 208 | itself using the low level df primitives. Currently no pass does |
3072d30e | 209 | this, but it has the advantage that it is quite efficient given |
210 | that the pass generally has exact knowledge of what it is changing. | |
211 | ||
212 | DATA STRUCTURES | |
e011eba9 | 213 | |
214 | Scanning produces a `struct df_ref' data structure (ref) is allocated | |
215 | for every register reference (def or use) and this records the insn | |
216 | and bb the ref is found within. The refs are linked together in | |
217 | chains of uses and defs for each insn and for each register. Each ref | |
218 | also has a chain field that links all the use refs for a def or all | |
219 | the def refs for a use. This is used to create use-def or def-use | |
220 | chains. | |
221 | ||
222 | Different optimizations have different needs. Ultimately, only | |
223 | register allocation and schedulers should be using the bitmaps | |
224 | produced for the live register and uninitialized register problems. | |
225 | The rest of the backend should be upgraded to using and maintaining | |
226 | the linked information such as def use or use def chains. | |
227 | ||
228 | ||
e011eba9 | 229 | PHILOSOPHY: |
230 | ||
231 | While incremental bitmaps are not worthwhile to maintain, incremental | |
232 | chains may be perfectly reasonable. The fastest way to build chains | |
233 | from scratch or after significant modifications is to build reaching | |
234 | definitions (RD) and build the chains from this. | |
235 | ||
236 | However, general algorithms for maintaining use-def or def-use chains | |
237 | are not practical. The amount of work to recompute the chain any | |
238 | chain after an arbitrary change is large. However, with a modest | |
239 | amount of work it is generally possible to have the application that | |
240 | uses the chains keep them up to date. The high level knowledge of | |
241 | what is really happening is essential to crafting efficient | |
242 | incremental algorithms. | |
243 | ||
244 | As for the bit vector problems, there is no interface to give a set of | |
245 | blocks over with to resolve the iteration. In general, restarting a | |
246 | dataflow iteration is difficult and expensive. Again, the best way to | |
554f2707 | 247 | keep the dataflow information up to data (if this is really what is |
e011eba9 | 248 | needed) it to formulate a problem specific solution. |
249 | ||
250 | There are fine grained calls for creating and deleting references from | |
251 | instructions in df-scan.c. However, these are not currently connected | |
252 | to the engine that resolves the dataflow equations. | |
253 | ||
254 | ||
255 | DATA STRUCTURES: | |
256 | ||
257 | The basic object is a DF_REF (reference) and this may either be a | |
258 | DEF (definition) or a USE of a register. | |
259 | ||
260 | These are linked into a variety of lists; namely reg-def, reg-use, | |
261 | insn-def, insn-use, def-use, and use-def lists. For example, the | |
262 | reg-def lists contain all the locations that define a given register | |
263 | while the insn-use lists contain all the locations that use a | |
264 | register. | |
265 | ||
266 | Note that the reg-def and reg-use chains are generally short for | |
267 | pseudos and long for the hard registers. | |
268 | ||
3072d30e | 269 | ACCESSING INSNS: |
270 | ||
271 | 1) The df insn information is kept in the insns array. This array is | |
272 | indexed by insn uid. | |
273 | ||
274 | 2) Each insn has three sets of refs: They are linked into one of three | |
275 | lists: the insn's defs list (accessed by the DF_INSN_DEFS or | |
276 | DF_INSN_UID_DEFS macros), the insn's uses list (accessed by the | |
277 | DF_INSN_USES or DF_INSN_UID_USES macros) or the insn's eq_uses list | |
278 | (accessed by the DF_INSN_EQ_USES or DF_INSN_UID_EQ_USES macros). | |
279 | The latter list are the list of references in REG_EQUAL or | |
280 | REG_EQUIV notes. These macros produce a ref (or NULL), the rest of | |
281 | the list can be obtained by traversal of the NEXT_REF field | |
282 | (accessed by the DF_REF_NEXT_REF macro.) There is no significance | |
283 | to the ordering of the uses or refs in an instruction. | |
284 | ||
285 | 3) Each insn has a logical uid field (LUID). When properly set, this | |
286 | is an integer that numbers each insn in the basic block, in order from | |
287 | the start of the block. The numbers are only correct after a call to | |
288 | df_analyse. They will rot after insns are added deleted or moved | |
289 | around. | |
290 | ||
e011eba9 | 291 | ACCESSING REFS: |
292 | ||
293 | There are 4 ways to obtain access to refs: | |
294 | ||
295 | 1) References are divided into two categories, REAL and ARTIFICIAL. | |
296 | ||
3072d30e | 297 | REAL refs are associated with instructions. |
e011eba9 | 298 | |
299 | ARTIFICIAL refs are associated with basic blocks. The heads of | |
3072d30e | 300 | these lists can be accessed by calling df_get_artificial_defs or |
301 | df_get_artificial_uses for the particular basic block. | |
e011eba9 | 302 | |
fcf2ad9f | 303 | Artificial defs and uses occur both at the beginning and ends of blocks. |
304 | ||
305 | For blocks that area at the destination of eh edges, the | |
306 | artificial uses and defs occur at the beginning. The defs relate | |
307 | to the registers specified in EH_RETURN_DATA_REGNO and the uses | |
308 | relate to the registers specified in ED_USES. Logically these | |
309 | defs and uses should really occur along the eh edge, but there is | |
310 | no convenient way to do this. Artificial edges that occur at the | |
311 | beginning of the block have the DF_REF_AT_TOP flag set. | |
312 | ||
313 | Artificial uses occur at the end of all blocks. These arise from | |
314 | the hard registers that are always live, such as the stack | |
315 | register and are put there to keep the code from forgetting about | |
316 | them. | |
317 | ||
334ec2d8 | 318 | Artificial defs occur at the end of the entry block. These arise |
fcf2ad9f | 319 | from registers that are live at entry to the function. |
e011eba9 | 320 | |
3072d30e | 321 | 2) There are three types of refs: defs, uses and eq_uses. (Eq_uses are |
322 | uses that appear inside a REG_EQUAL or REG_EQUIV note.) | |
e011eba9 | 323 | |
3072d30e | 324 | All of the eq_uses, uses and defs associated with each pseudo or |
325 | hard register may be linked in a bidirectional chain. These are | |
326 | called reg-use or reg_def chains. If the changeable flag | |
327 | DF_EQ_NOTES is set when the chains are built, the eq_uses will be | |
328 | treated like uses. If it is not set they are ignored. | |
329 | ||
330 | The first use, eq_use or def for a register can be obtained using | |
331 | the DF_REG_USE_CHAIN, DF_REG_EQ_USE_CHAIN or DF_REG_DEF_CHAIN | |
332 | macros. Subsequent uses for the same regno can be obtained by | |
333 | following the next_reg field of the ref. The number of elements in | |
334 | each of the chains can be found by using the DF_REG_USE_COUNT, | |
335 | DF_REG_EQ_USE_COUNT or DF_REG_DEF_COUNT macros. | |
e011eba9 | 336 | |
337 | In previous versions of this code, these chains were ordered. It | |
338 | has not been practical to continue this practice. | |
339 | ||
340 | 3) If def-use or use-def chains are built, these can be traversed to | |
3072d30e | 341 | get to other refs. If the flag DF_EQ_NOTES has been set, the chains |
342 | include the eq_uses. Otherwise these are ignored when building the | |
343 | chains. | |
e011eba9 | 344 | |
345 | 4) An array of all of the uses (and an array of all of the defs) can | |
3072d30e | 346 | |
e011eba9 | 347 | be built. These arrays are indexed by the value in the id |
348 | structure. These arrays are only lazily kept up to date, and that | |
349 | process can be expensive. To have these arrays built, call | |
3072d30e | 350 | df_reorganize_defs or df_reorganize_uses. If the flag DF_EQ_NOTES |
351 | has been set the array will contain the eq_uses. Otherwise these | |
352 | are ignored when building the array and assigning the ids. Note | |
353 | that the values in the id field of a ref may change across calls to | |
354 | df_analyze or df_reorganize_defs or df_reorganize_uses. | |
e011eba9 | 355 | |
356 | If the only use of this array is to find all of the refs, it is | |
357 | better to traverse all of the registers and then traverse all of | |
358 | reg-use or reg-def chains. | |
359 | ||
e011eba9 | 360 | NOTES: |
361 | ||
362 | Embedded addressing side-effects, such as POST_INC or PRE_INC, generate | |
363 | both a use and a def. These are both marked read/write to show that they | |
364 | are dependent. For example, (set (reg 40) (mem (post_inc (reg 42)))) | |
365 | will generate a use of reg 42 followed by a def of reg 42 (both marked | |
366 | read/write). Similarly, (set (reg 40) (mem (pre_dec (reg 41)))) | |
367 | generates a use of reg 41 then a def of reg 41 (both marked read/write), | |
368 | even though reg 41 is decremented before it is used for the memory | |
369 | address in this second example. | |
370 | ||
371 | A set to a REG inside a ZERO_EXTRACT, or a set to a non-paradoxical SUBREG | |
372 | for which the number of word_mode units covered by the outer mode is | |
373 | smaller than that covered by the inner mode, invokes a read-modify-write. | |
374 | operation. We generate both a use and a def and again mark them | |
375 | read/write. | |
376 | ||
377 | Paradoxical subreg writes do not leave a trace of the old content, so they | |
378 | are write-only operations. | |
379 | */ | |
380 | ||
381 | ||
382 | #include "config.h" | |
383 | #include "system.h" | |
384 | #include "coretypes.h" | |
385 | #include "tm.h" | |
386 | #include "rtl.h" | |
387 | #include "tm_p.h" | |
388 | #include "insn-config.h" | |
389 | #include "recog.h" | |
390 | #include "function.h" | |
391 | #include "regs.h" | |
392 | #include "output.h" | |
393 | #include "alloc-pool.h" | |
394 | #include "flags.h" | |
395 | #include "hard-reg-set.h" | |
396 | #include "basic-block.h" | |
397 | #include "sbitmap.h" | |
398 | #include "bitmap.h" | |
399 | #include "timevar.h" | |
400 | #include "df.h" | |
401 | #include "tree-pass.h" | |
402 | ||
3e6933a8 | 403 | static void *df_get_bb_info (struct dataflow *, unsigned int); |
f64e6a69 | 404 | static void df_set_bb_info (struct dataflow *, unsigned int, void *); |
3072d30e | 405 | #ifdef DF_DEBUG_CFG |
406 | static void df_set_clean_cfg (void); | |
407 | #endif | |
e011eba9 | 408 | |
3072d30e | 409 | /* An obstack for bitmap not related to specific dataflow problems. |
410 | This obstack should e.g. be used for bitmaps with a short life time | |
411 | such as temporary bitmaps. */ | |
e011eba9 | 412 | |
3072d30e | 413 | bitmap_obstack df_bitmap_obstack; |
e011eba9 | 414 | |
e011eba9 | 415 | |
3072d30e | 416 | /*---------------------------------------------------------------------------- |
417 | Functions to create, destroy and manipulate an instance of df. | |
418 | ----------------------------------------------------------------------------*/ | |
419 | ||
420 | struct df *df; | |
e011eba9 | 421 | |
3072d30e | 422 | /* Add PROBLEM (and any dependent problems) to the DF instance. */ |
e011eba9 | 423 | |
3072d30e | 424 | void |
425 | df_add_problem (struct df_problem *problem) | |
e011eba9 | 426 | { |
427 | struct dataflow *dflow; | |
3072d30e | 428 | int i; |
e011eba9 | 429 | |
430 | /* First try to add the dependent problem. */ | |
3072d30e | 431 | if (problem->dependent_problem) |
432 | df_add_problem (problem->dependent_problem); | |
e011eba9 | 433 | |
434 | /* Check to see if this problem has already been defined. If it | |
435 | has, just return that instance, if not, add it to the end of the | |
436 | vector. */ | |
437 | dflow = df->problems_by_index[problem->id]; | |
438 | if (dflow) | |
3072d30e | 439 | return; |
e011eba9 | 440 | |
441 | /* Make a new one and add it to the end. */ | |
4c36ffe6 | 442 | dflow = XCNEW (struct dataflow); |
e011eba9 | 443 | dflow->problem = problem; |
3072d30e | 444 | dflow->computed = false; |
445 | dflow->solutions_dirty = true; | |
e011eba9 | 446 | df->problems_by_index[dflow->problem->id] = dflow; |
447 | ||
3072d30e | 448 | /* Keep the defined problems ordered by index. This solves the |
449 | problem that RI will use the information from UREC if UREC has | |
450 | been defined, or from LIVE if LIVE is defined and otherwise LR. | |
451 | However for this to work, the computation of RI must be pushed | |
452 | after which ever of those problems is defined, but we do not | |
453 | require any of those except for LR to have actually been | |
454 | defined. */ | |
455 | df->num_problems_defined++; | |
456 | for (i = df->num_problems_defined - 2; i >= 0; i--) | |
457 | { | |
458 | if (problem->id < df->problems_in_order[i]->problem->id) | |
459 | df->problems_in_order[i+1] = df->problems_in_order[i]; | |
460 | else | |
461 | { | |
462 | df->problems_in_order[i+1] = dflow; | |
463 | return; | |
464 | } | |
465 | } | |
466 | df->problems_in_order[0] = dflow; | |
e011eba9 | 467 | } |
468 | ||
469 | ||
3e6933a8 | 470 | /* Set the MASK flags in the DFLOW problem. The old flags are |
471 | returned. If a flag is not allowed to be changed this will fail if | |
472 | checking is enabled. */ | |
3072d30e | 473 | enum df_changeable_flags |
474 | df_set_flags (enum df_changeable_flags changeable_flags) | |
3e6933a8 | 475 | { |
3072d30e | 476 | enum df_changeable_flags old_flags = df->changeable_flags; |
477 | df->changeable_flags |= changeable_flags; | |
3e6933a8 | 478 | return old_flags; |
479 | } | |
480 | ||
3072d30e | 481 | |
3e6933a8 | 482 | /* Clear the MASK flags in the DFLOW problem. The old flags are |
483 | returned. If a flag is not allowed to be changed this will fail if | |
484 | checking is enabled. */ | |
3072d30e | 485 | enum df_changeable_flags |
486 | df_clear_flags (enum df_changeable_flags changeable_flags) | |
3e6933a8 | 487 | { |
3072d30e | 488 | enum df_changeable_flags old_flags = df->changeable_flags; |
489 | df->changeable_flags &= ~changeable_flags; | |
3e6933a8 | 490 | return old_flags; |
491 | } | |
492 | ||
3072d30e | 493 | |
e011eba9 | 494 | /* Set the blocks that are to be considered for analysis. If this is |
495 | not called or is called with null, the entire function in | |
496 | analyzed. */ | |
497 | ||
498 | void | |
3072d30e | 499 | df_set_blocks (bitmap blocks) |
e011eba9 | 500 | { |
501 | if (blocks) | |
502 | { | |
3072d30e | 503 | if (dump_file) |
504 | bitmap_print (dump_file, blocks, "setting blocks to analyze ", "\n"); | |
d0802b39 | 505 | if (df->blocks_to_analyze) |
506 | { | |
deb2741b | 507 | /* This block is called to change the focus from one subset |
508 | to another. */ | |
d0802b39 | 509 | int p; |
3072d30e | 510 | bitmap diff = BITMAP_ALLOC (&df_bitmap_obstack); |
d0802b39 | 511 | bitmap_and_compl (diff, df->blocks_to_analyze, blocks); |
deb2741b | 512 | for (p = 0; p < df->num_problems_defined; p++) |
d0802b39 | 513 | { |
514 | struct dataflow *dflow = df->problems_in_order[p]; | |
deb2741b | 515 | if (dflow->optional_p && dflow->problem->reset_fun) |
3072d30e | 516 | dflow->problem->reset_fun (df->blocks_to_analyze); |
deb2741b | 517 | else if (dflow->problem->free_blocks_on_set_blocks) |
d0802b39 | 518 | { |
519 | bitmap_iterator bi; | |
520 | unsigned int bb_index; | |
521 | ||
522 | EXECUTE_IF_SET_IN_BITMAP (diff, 0, bb_index, bi) | |
523 | { | |
524 | basic_block bb = BASIC_BLOCK (bb_index); | |
f64e6a69 | 525 | if (bb) |
526 | { | |
3072d30e | 527 | void *bb_info = df_get_bb_info (dflow, bb_index); |
528 | if (bb_info) | |
529 | { | |
530 | dflow->problem->free_bb_fun (bb, bb_info); | |
531 | df_set_bb_info (dflow, bb_index, NULL); | |
532 | } | |
f64e6a69 | 533 | } |
d0802b39 | 534 | } |
535 | } | |
536 | } | |
537 | ||
538 | BITMAP_FREE (diff); | |
539 | } | |
540 | else | |
f64e6a69 | 541 | { |
deb2741b | 542 | /* This block of code is executed to change the focus from |
543 | the entire function to a subset. */ | |
544 | bitmap blocks_to_reset = NULL; | |
545 | int p; | |
546 | for (p = 0; p < df->num_problems_defined; p++) | |
f64e6a69 | 547 | { |
deb2741b | 548 | struct dataflow *dflow = df->problems_in_order[p]; |
549 | if (dflow->optional_p && dflow->problem->reset_fun) | |
f64e6a69 | 550 | { |
deb2741b | 551 | if (!blocks_to_reset) |
f64e6a69 | 552 | { |
deb2741b | 553 | basic_block bb; |
554 | blocks_to_reset = | |
555 | BITMAP_ALLOC (&df_bitmap_obstack); | |
556 | FOR_ALL_BB(bb) | |
f64e6a69 | 557 | { |
deb2741b | 558 | bitmap_set_bit (blocks_to_reset, bb->index); |
f64e6a69 | 559 | } |
f64e6a69 | 560 | } |
deb2741b | 561 | dflow->problem->reset_fun (blocks_to_reset); |
f64e6a69 | 562 | } |
f64e6a69 | 563 | } |
deb2741b | 564 | if (blocks_to_reset) |
565 | BITMAP_FREE (blocks_to_reset); | |
566 | ||
3072d30e | 567 | df->blocks_to_analyze = BITMAP_ALLOC (&df_bitmap_obstack); |
f64e6a69 | 568 | } |
e011eba9 | 569 | bitmap_copy (df->blocks_to_analyze, blocks); |
3072d30e | 570 | df->analyze_subset = true; |
e011eba9 | 571 | } |
572 | else | |
573 | { | |
deb2741b | 574 | /* This block is executed to reset the focus to the entire |
575 | function. */ | |
3072d30e | 576 | if (dump_file) |
deb2741b | 577 | fprintf (dump_file, "clearing blocks_to_analyze\n"); |
e011eba9 | 578 | if (df->blocks_to_analyze) |
579 | { | |
580 | BITMAP_FREE (df->blocks_to_analyze); | |
581 | df->blocks_to_analyze = NULL; | |
582 | } | |
3072d30e | 583 | df->analyze_subset = false; |
e011eba9 | 584 | } |
3072d30e | 585 | |
586 | /* Setting the blocks causes the refs to be unorganized since only | |
587 | the refs in the blocks are seen. */ | |
588 | df_maybe_reorganize_def_refs (DF_REF_ORDER_NO_TABLE); | |
589 | df_maybe_reorganize_use_refs (DF_REF_ORDER_NO_TABLE); | |
590 | df_mark_solutions_dirty (); | |
e011eba9 | 591 | } |
592 | ||
593 | ||
3072d30e | 594 | /* Delete a DFLOW problem (and any problems that depend on this |
595 | problem). */ | |
3e6933a8 | 596 | |
597 | void | |
3072d30e | 598 | df_remove_problem (struct dataflow *dflow) |
3e6933a8 | 599 | { |
3072d30e | 600 | struct df_problem *problem; |
3e6933a8 | 601 | int i; |
3072d30e | 602 | |
603 | if (!dflow) | |
604 | return; | |
605 | ||
606 | problem = dflow->problem; | |
607 | gcc_assert (problem->remove_problem_fun); | |
608 | ||
3072d30e | 609 | /* Delete any problems that depended on this problem first. */ |
deb2741b | 610 | for (i = 0; i < df->num_problems_defined; i++) |
3072d30e | 611 | if (df->problems_in_order[i]->problem->dependent_problem == problem) |
612 | df_remove_problem (df->problems_in_order[i]); | |
613 | ||
614 | /* Now remove this problem. */ | |
deb2741b | 615 | for (i = 0; i < df->num_problems_defined; i++) |
3072d30e | 616 | if (df->problems_in_order[i] == dflow) |
617 | { | |
618 | int j; | |
619 | for (j = i + 1; j < df->num_problems_defined; j++) | |
620 | df->problems_in_order[j-1] = df->problems_in_order[j]; | |
621 | df->problems_in_order[j] = NULL; | |
622 | df->num_problems_defined--; | |
623 | break; | |
624 | } | |
625 | ||
626 | (problem->remove_problem_fun) (); | |
627 | df->problems_by_index[problem->id] = NULL; | |
628 | } | |
629 | ||
630 | ||
84da8954 | 631 | /* Remove all of the problems that are not permanent. Scanning, LR |
632 | and (at -O2 or higher) LIVE are permanent, the rest are removable. | |
633 | Also clear all of the changeable_flags. */ | |
3072d30e | 634 | |
635 | void | |
314966f4 | 636 | df_finish_pass (bool verify ATTRIBUTE_UNUSED) |
3072d30e | 637 | { |
638 | int i; | |
639 | int removed = 0; | |
640 | ||
5ccba2dc | 641 | #ifdef ENABLE_DF_CHECKING |
3072d30e | 642 | enum df_changeable_flags saved_flags; |
643 | #endif | |
644 | ||
645 | if (!df) | |
646 | return; | |
647 | ||
648 | df_maybe_reorganize_def_refs (DF_REF_ORDER_NO_TABLE); | |
649 | df_maybe_reorganize_use_refs (DF_REF_ORDER_NO_TABLE); | |
650 | ||
5ccba2dc | 651 | #ifdef ENABLE_DF_CHECKING |
3072d30e | 652 | saved_flags = df->changeable_flags; |
653 | #endif | |
654 | ||
deb2741b | 655 | for (i = 0; i < df->num_problems_defined; i++) |
3e6933a8 | 656 | { |
657 | struct dataflow *dflow = df->problems_in_order[i]; | |
3072d30e | 658 | struct df_problem *problem = dflow->problem; |
659 | ||
deb2741b | 660 | if (dflow->optional_p) |
661 | { | |
662 | gcc_assert (problem->remove_problem_fun); | |
663 | (problem->remove_problem_fun) (); | |
664 | df->problems_in_order[i] = NULL; | |
665 | df->problems_by_index[problem->id] = NULL; | |
666 | removed++; | |
667 | } | |
3072d30e | 668 | } |
669 | df->num_problems_defined -= removed; | |
670 | ||
671 | /* Clear all of the flags. */ | |
672 | df->changeable_flags = 0; | |
673 | df_process_deferred_rescans (); | |
674 | ||
675 | /* Set the focus back to the whole function. */ | |
676 | if (df->blocks_to_analyze) | |
677 | { | |
678 | BITMAP_FREE (df->blocks_to_analyze); | |
679 | df->blocks_to_analyze = NULL; | |
680 | df_mark_solutions_dirty (); | |
681 | df->analyze_subset = false; | |
3e6933a8 | 682 | } |
3072d30e | 683 | |
5ccba2dc | 684 | #ifdef ENABLE_DF_CHECKING |
3072d30e | 685 | /* Verification will fail in DF_NO_INSN_RESCAN. */ |
686 | if (!(saved_flags & DF_NO_INSN_RESCAN)) | |
687 | { | |
688 | df_lr_verify_transfer_functions (); | |
689 | if (df_live) | |
690 | df_live_verify_transfer_functions (); | |
691 | } | |
692 | ||
693 | #ifdef DF_DEBUG_CFG | |
694 | df_set_clean_cfg (); | |
695 | #endif | |
696 | #endif | |
314966f4 | 697 | |
698 | #ifdef ENABLE_CHECKING | |
699 | if (verify) | |
700 | df->changeable_flags |= DF_VERIFY_SCHEDULED; | |
701 | #endif | |
3072d30e | 702 | } |
703 | ||
704 | ||
705 | /* Set up the dataflow instance for the entire back end. */ | |
706 | ||
707 | static unsigned int | |
708 | rest_of_handle_df_initialize (void) | |
709 | { | |
710 | gcc_assert (!df); | |
711 | df = XCNEW (struct df); | |
712 | df->changeable_flags = 0; | |
713 | ||
714 | bitmap_obstack_initialize (&df_bitmap_obstack); | |
715 | ||
716 | /* Set this to a conservative value. Stack_ptr_mod will compute it | |
717 | correctly later. */ | |
718 | current_function_sp_is_unchanging = 0; | |
719 | ||
720 | df_scan_add_problem (); | |
721 | df_scan_alloc (NULL); | |
722 | ||
723 | /* These three problems are permanent. */ | |
724 | df_lr_add_problem (); | |
deb2741b | 725 | if (optimize > 1) |
3072d30e | 726 | df_live_add_problem (); |
727 | ||
728 | df->postorder = XNEWVEC (int, last_basic_block); | |
729 | df->postorder_inverted = XNEWVEC (int, last_basic_block); | |
730 | df->n_blocks = post_order_compute (df->postorder, true, true); | |
731 | df->n_blocks_inverted = inverted_post_order_compute (df->postorder_inverted); | |
732 | gcc_assert (df->n_blocks == df->n_blocks_inverted); | |
733 | ||
734 | df->hard_regs_live_count = XNEWVEC (unsigned int, FIRST_PSEUDO_REGISTER); | |
735 | memset (df->hard_regs_live_count, 0, | |
736 | sizeof (unsigned int) * FIRST_PSEUDO_REGISTER); | |
737 | ||
738 | df_hard_reg_init (); | |
739 | /* After reload, some ports add certain bits to regs_ever_live so | |
740 | this cannot be reset. */ | |
741 | df_compute_regs_ever_live (true); | |
742 | df_scan_blocks (); | |
743 | df_compute_regs_ever_live (false); | |
744 | return 0; | |
745 | } | |
746 | ||
747 | ||
748 | static bool | |
749 | gate_opt (void) | |
750 | { | |
751 | return optimize > 0; | |
3e6933a8 | 752 | } |
753 | ||
754 | ||
3072d30e | 755 | struct tree_opt_pass pass_df_initialize_opt = |
756 | { | |
757 | "dfinit", /* name */ | |
758 | gate_opt, /* gate */ | |
759 | rest_of_handle_df_initialize, /* execute */ | |
760 | NULL, /* sub */ | |
761 | NULL, /* next */ | |
762 | 0, /* static_pass_number */ | |
763 | 0, /* tv_id */ | |
764 | 0, /* properties_required */ | |
765 | 0, /* properties_provided */ | |
766 | 0, /* properties_destroyed */ | |
767 | 0, /* todo_flags_start */ | |
768 | 0, /* todo_flags_finish */ | |
769 | 'z' /* letter */ | |
770 | }; | |
771 | ||
772 | ||
773 | static bool | |
774 | gate_no_opt (void) | |
775 | { | |
776 | return optimize == 0; | |
777 | } | |
778 | ||
779 | ||
780 | struct tree_opt_pass pass_df_initialize_no_opt = | |
781 | { | |
782 | "dfinit", /* name */ | |
783 | gate_no_opt, /* gate */ | |
784 | rest_of_handle_df_initialize, /* execute */ | |
785 | NULL, /* sub */ | |
786 | NULL, /* next */ | |
787 | 0, /* static_pass_number */ | |
788 | 0, /* tv_id */ | |
789 | 0, /* properties_required */ | |
790 | 0, /* properties_provided */ | |
791 | 0, /* properties_destroyed */ | |
792 | 0, /* todo_flags_start */ | |
793 | 0, /* todo_flags_finish */ | |
794 | 'z' /* letter */ | |
795 | }; | |
796 | ||
797 | ||
e011eba9 | 798 | /* Free all the dataflow info and the DF structure. This should be |
799 | called from the df_finish macro which also NULLs the parm. */ | |
800 | ||
3072d30e | 801 | static unsigned int |
802 | rest_of_handle_df_finish (void) | |
e011eba9 | 803 | { |
804 | int i; | |
805 | ||
3072d30e | 806 | gcc_assert (df); |
807 | ||
e011eba9 | 808 | for (i = 0; i < df->num_problems_defined; i++) |
3072d30e | 809 | { |
810 | struct dataflow *dflow = df->problems_in_order[i]; | |
811 | dflow->problem->free_fun (); | |
812 | } | |
e011eba9 | 813 | |
3072d30e | 814 | if (df->postorder) |
815 | free (df->postorder); | |
816 | if (df->postorder_inverted) | |
817 | free (df->postorder_inverted); | |
818 | free (df->hard_regs_live_count); | |
e011eba9 | 819 | free (df); |
3072d30e | 820 | df = NULL; |
821 | ||
822 | bitmap_obstack_release (&df_bitmap_obstack); | |
823 | return 0; | |
e011eba9 | 824 | } |
825 | ||
3072d30e | 826 | |
827 | struct tree_opt_pass pass_df_finish = | |
828 | { | |
829 | "dfinish", /* name */ | |
830 | NULL, /* gate */ | |
831 | rest_of_handle_df_finish, /* execute */ | |
832 | NULL, /* sub */ | |
833 | NULL, /* next */ | |
834 | 0, /* static_pass_number */ | |
835 | 0, /* tv_id */ | |
836 | 0, /* properties_required */ | |
837 | 0, /* properties_provided */ | |
838 | 0, /* properties_destroyed */ | |
839 | 0, /* todo_flags_start */ | |
840 | 0, /* todo_flags_finish */ | |
841 | 'z' /* letter */ | |
842 | }; | |
843 | ||
844 | ||
845 | ||
846 | ||
e011eba9 | 847 | \f |
848 | /*---------------------------------------------------------------------------- | |
849 | The general data flow analysis engine. | |
850 | ----------------------------------------------------------------------------*/ | |
851 | ||
852 | ||
3072d30e | 853 | /* Helper function for df_worklist_dataflow. |
854 | Propagate the dataflow forward. | |
855 | Given a BB_INDEX, do the dataflow propagation | |
856 | and set bits on for successors in PENDING | |
857 | if the out set of the dataflow has changed. */ | |
e011eba9 | 858 | |
859 | static void | |
3072d30e | 860 | df_worklist_propagate_forward (struct dataflow *dataflow, |
861 | unsigned bb_index, | |
862 | unsigned *bbindex_to_postorder, | |
863 | bitmap pending, | |
864 | sbitmap considered) | |
e011eba9 | 865 | { |
e011eba9 | 866 | edge e; |
867 | edge_iterator ei; | |
3072d30e | 868 | basic_block bb = BASIC_BLOCK (bb_index); |
e011eba9 | 869 | |
3072d30e | 870 | /* Calculate <conf_op> of incoming edges. */ |
e011eba9 | 871 | if (EDGE_COUNT (bb->preds) > 0) |
872 | FOR_EACH_EDGE (e, ei, bb->preds) | |
3072d30e | 873 | { |
874 | if (TEST_BIT (considered, e->src->index)) | |
875 | dataflow->problem->con_fun_n (e); | |
876 | } | |
1c1a6437 | 877 | else if (dataflow->problem->con_fun_0) |
3072d30e | 878 | dataflow->problem->con_fun_0 (bb); |
879 | ||
880 | if (dataflow->problem->trans_fun (bb_index)) | |
e011eba9 | 881 | { |
3072d30e | 882 | /* The out set of this block has changed. |
883 | Propagate to the outgoing blocks. */ | |
884 | FOR_EACH_EDGE (e, ei, bb->succs) | |
885 | { | |
886 | unsigned ob_index = e->dest->index; | |
887 | ||
888 | if (TEST_BIT (considered, ob_index)) | |
889 | bitmap_set_bit (pending, bbindex_to_postorder[ob_index]); | |
890 | } | |
e011eba9 | 891 | } |
892 | } | |
893 | ||
3072d30e | 894 | |
895 | /* Helper function for df_worklist_dataflow. | |
896 | Propagate the dataflow backward. */ | |
897 | ||
e011eba9 | 898 | static void |
3072d30e | 899 | df_worklist_propagate_backward (struct dataflow *dataflow, |
900 | unsigned bb_index, | |
901 | unsigned *bbindex_to_postorder, | |
902 | bitmap pending, | |
903 | sbitmap considered) | |
e011eba9 | 904 | { |
e011eba9 | 905 | edge e; |
906 | edge_iterator ei; | |
3072d30e | 907 | basic_block bb = BASIC_BLOCK (bb_index); |
e011eba9 | 908 | |
3072d30e | 909 | /* Calculate <conf_op> of incoming edges. */ |
e011eba9 | 910 | if (EDGE_COUNT (bb->succs) > 0) |
3072d30e | 911 | FOR_EACH_EDGE (e, ei, bb->succs) |
e011eba9 | 912 | { |
3072d30e | 913 | if (TEST_BIT (considered, e->dest->index)) |
914 | dataflow->problem->con_fun_n (e); | |
e011eba9 | 915 | } |
1c1a6437 | 916 | else if (dataflow->problem->con_fun_0) |
3072d30e | 917 | dataflow->problem->con_fun_0 (bb); |
e011eba9 | 918 | |
3072d30e | 919 | if (dataflow->problem->trans_fun (bb_index)) |
e011eba9 | 920 | { |
3072d30e | 921 | /* The out set of this block has changed. |
922 | Propagate to the outgoing blocks. */ | |
923 | FOR_EACH_EDGE (e, ei, bb->preds) | |
924 | { | |
925 | unsigned ob_index = e->src->index; | |
926 | ||
927 | if (TEST_BIT (considered, ob_index)) | |
928 | bitmap_set_bit (pending, bbindex_to_postorder[ob_index]); | |
929 | } | |
e011eba9 | 930 | } |
931 | } | |
932 | ||
933 | ||
3072d30e | 934 | /* Worklist-based dataflow solver. It uses sbitmap as a worklist, |
935 | with "n"-th bit representing the n-th block in the reverse-postorder order. | |
936 | This is so-called over-eager algorithm where it propagates | |
937 | changes on demand. This algorithm may visit blocks more than | |
938 | iterative method if there are deeply nested loops. | |
939 | Worklist algorithm works better than iterative algorithm | |
940 | for CFGs with no nested loops. | |
941 | In practice, the measurement shows worklist algorithm beats | |
942 | iterative algorithm by some margin overall. | |
943 | Note that this is slightly different from the traditional textbook worklist solver, | |
944 | in that the worklist is effectively sorted by the reverse postorder. | |
945 | For CFGs with no nested loops, this is optimal. */ | |
e011eba9 | 946 | |
3072d30e | 947 | void |
948 | df_worklist_dataflow (struct dataflow *dataflow, | |
949 | bitmap blocks_to_consider, | |
950 | int *blocks_in_postorder, | |
951 | int n_blocks) | |
e011eba9 | 952 | { |
3072d30e | 953 | bitmap pending = BITMAP_ALLOC (&df_bitmap_obstack); |
e011eba9 | 954 | sbitmap considered = sbitmap_alloc (last_basic_block); |
955 | bitmap_iterator bi; | |
3072d30e | 956 | unsigned int *bbindex_to_postorder; |
957 | int i; | |
958 | unsigned int index; | |
959 | enum df_flow_dir dir = dataflow->problem->dir; | |
e011eba9 | 960 | |
3072d30e | 961 | gcc_assert (dir != DF_NONE); |
e011eba9 | 962 | |
3072d30e | 963 | /* BBINDEX_TO_POSTORDER maps the bb->index to the reverse postorder. */ |
964 | bbindex_to_postorder = | |
965 | (unsigned int *)xmalloc (last_basic_block * sizeof (unsigned int)); | |
e011eba9 | 966 | |
3072d30e | 967 | /* Initialize the array to an out-of-bound value. */ |
968 | for (i = 0; i < last_basic_block; i++) | |
969 | bbindex_to_postorder[i] = last_basic_block; | |
3e6933a8 | 970 | |
3072d30e | 971 | /* Initialize the considered map. */ |
972 | sbitmap_zero (considered); | |
973 | EXECUTE_IF_SET_IN_BITMAP (blocks_to_consider, 0, index, bi) | |
e011eba9 | 974 | { |
3072d30e | 975 | SET_BIT (considered, index); |
e011eba9 | 976 | } |
977 | ||
3072d30e | 978 | /* Initialize the mapping of block index to postorder. */ |
e011eba9 | 979 | for (i = 0; i < n_blocks; i++) |
980 | { | |
3072d30e | 981 | bbindex_to_postorder[blocks_in_postorder[i]] = i; |
982 | /* Add all blocks to the worklist. */ | |
983 | bitmap_set_bit (pending, i); | |
984 | } | |
e011eba9 | 985 | |
3072d30e | 986 | if (dataflow->problem->init_fun) |
987 | dataflow->problem->init_fun (blocks_to_consider); | |
e011eba9 | 988 | |
3072d30e | 989 | while (!bitmap_empty_p (pending)) |
e011eba9 | 990 | { |
3072d30e | 991 | unsigned bb_index; |
e011eba9 | 992 | |
3072d30e | 993 | index = bitmap_first_set_bit (pending); |
994 | bitmap_clear_bit (pending, index); | |
e011eba9 | 995 | |
3072d30e | 996 | bb_index = blocks_in_postorder[index]; |
e011eba9 | 997 | |
3072d30e | 998 | if (dir == DF_FORWARD) |
999 | df_worklist_propagate_forward (dataflow, bb_index, | |
1000 | bbindex_to_postorder, | |
1001 | pending, considered); | |
1002 | else | |
1003 | df_worklist_propagate_backward (dataflow, bb_index, | |
1004 | bbindex_to_postorder, | |
1005 | pending, considered); | |
e011eba9 | 1006 | } |
1007 | ||
3072d30e | 1008 | BITMAP_FREE (pending); |
e011eba9 | 1009 | sbitmap_free (considered); |
3072d30e | 1010 | free (bbindex_to_postorder); |
e011eba9 | 1011 | } |
1012 | ||
1013 | ||
1014 | /* Remove the entries not in BLOCKS from the LIST of length LEN, preserving | |
1015 | the order of the remaining entries. Returns the length of the resulting | |
1016 | list. */ | |
1017 | ||
1018 | static unsigned | |
1019 | df_prune_to_subcfg (int list[], unsigned len, bitmap blocks) | |
1020 | { | |
1021 | unsigned act, last; | |
1022 | ||
1023 | for (act = 0, last = 0; act < len; act++) | |
1024 | if (bitmap_bit_p (blocks, list[act])) | |
1025 | list[last++] = list[act]; | |
1026 | ||
1027 | return last; | |
1028 | } | |
1029 | ||
1030 | ||
1031 | /* Execute dataflow analysis on a single dataflow problem. | |
1032 | ||
e011eba9 | 1033 | BLOCKS_TO_CONSIDER are the blocks whose solution can either be |
1034 | examined or will be computed. For calls from DF_ANALYZE, this is | |
3072d30e | 1035 | the set of blocks that has been passed to DF_SET_BLOCKS. |
e011eba9 | 1036 | */ |
1037 | ||
3e6933a8 | 1038 | void |
e011eba9 | 1039 | df_analyze_problem (struct dataflow *dflow, |
1040 | bitmap blocks_to_consider, | |
3072d30e | 1041 | int *postorder, int n_blocks) |
e011eba9 | 1042 | { |
3072d30e | 1043 | timevar_push (dflow->problem->tv_id); |
1044 | ||
5ccba2dc | 1045 | #ifdef ENABLE_DF_CHECKING |
3072d30e | 1046 | if (dflow->problem->verify_start_fun) |
1047 | dflow->problem->verify_start_fun (); | |
1048 | #endif | |
1049 | ||
e011eba9 | 1050 | /* (Re)Allocate the datastructures necessary to solve the problem. */ |
1c1a6437 | 1051 | if (dflow->problem->alloc_fun) |
3072d30e | 1052 | dflow->problem->alloc_fun (blocks_to_consider); |
e011eba9 | 1053 | |
3072d30e | 1054 | /* Set up the problem and compute the local information. */ |
1c1a6437 | 1055 | if (dflow->problem->local_compute_fun) |
3072d30e | 1056 | dflow->problem->local_compute_fun (blocks_to_consider); |
e011eba9 | 1057 | |
1058 | /* Solve the equations. */ | |
1c1a6437 | 1059 | if (dflow->problem->dataflow_fun) |
3072d30e | 1060 | dflow->problem->dataflow_fun (dflow, blocks_to_consider, |
1061 | postorder, n_blocks); | |
e011eba9 | 1062 | |
1063 | /* Massage the solution. */ | |
1c1a6437 | 1064 | if (dflow->problem->finalize_fun) |
3072d30e | 1065 | dflow->problem->finalize_fun (blocks_to_consider); |
1066 | ||
5ccba2dc | 1067 | #ifdef ENABLE_DF_CHECKING |
3072d30e | 1068 | if (dflow->problem->verify_end_fun) |
1069 | dflow->problem->verify_end_fun (); | |
1070 | #endif | |
1071 | ||
1072 | timevar_pop (dflow->problem->tv_id); | |
1073 | ||
1074 | dflow->computed = true; | |
e011eba9 | 1075 | } |
1076 | ||
1077 | ||
1078 | /* Analyze dataflow info for the basic blocks specified by the bitmap | |
1079 | BLOCKS, or for the whole CFG if BLOCKS is zero. */ | |
1080 | ||
1081 | void | |
3072d30e | 1082 | df_analyze (void) |
e011eba9 | 1083 | { |
3072d30e | 1084 | bitmap current_all_blocks = BITMAP_ALLOC (&df_bitmap_obstack); |
e011eba9 | 1085 | bool everything; |
3072d30e | 1086 | int i; |
1087 | ||
1088 | if (df->postorder) | |
1089 | free (df->postorder); | |
1090 | if (df->postorder_inverted) | |
1091 | free (df->postorder_inverted); | |
1092 | df->postorder = XNEWVEC (int, last_basic_block); | |
1093 | df->postorder_inverted = XNEWVEC (int, last_basic_block); | |
1094 | df->n_blocks = post_order_compute (df->postorder, true, true); | |
1095 | df->n_blocks_inverted = inverted_post_order_compute (df->postorder_inverted); | |
1096 | ||
1097 | /* These should be the same. */ | |
1098 | gcc_assert (df->n_blocks == df->n_blocks_inverted); | |
1099 | ||
1100 | /* We need to do this before the df_verify_all because this is | |
1101 | not kept incrementally up to date. */ | |
1102 | df_compute_regs_ever_live (false); | |
1103 | df_process_deferred_rescans (); | |
1104 | ||
3072d30e | 1105 | if (dump_file) |
1106 | fprintf (dump_file, "df_analyze called\n"); | |
5ccba2dc | 1107 | |
314966f4 | 1108 | #ifndef ENABLE_DF_CHECKING |
1109 | if (df->changeable_flags & DF_VERIFY_SCHEDULED) | |
1110 | #endif | |
1111 | df_verify (); | |
3072d30e | 1112 | |
1113 | for (i = 0; i < df->n_blocks; i++) | |
1114 | bitmap_set_bit (current_all_blocks, df->postorder[i]); | |
1115 | ||
1116 | #ifdef ENABLE_CHECKING | |
1117 | /* Verify that POSTORDER_INVERTED only contains blocks reachable from | |
1118 | the ENTRY block. */ | |
1119 | for (i = 0; i < df->n_blocks_inverted; i++) | |
1120 | gcc_assert (bitmap_bit_p (current_all_blocks, df->postorder_inverted[i])); | |
1121 | #endif | |
e011eba9 | 1122 | |
1123 | /* Make sure that we have pruned any unreachable blocks from these | |
1124 | sets. */ | |
3072d30e | 1125 | if (df->analyze_subset) |
e011eba9 | 1126 | { |
1127 | everything = false; | |
1128 | bitmap_and_into (df->blocks_to_analyze, current_all_blocks); | |
3072d30e | 1129 | df->n_blocks = df_prune_to_subcfg (df->postorder, |
1130 | df->n_blocks, df->blocks_to_analyze); | |
1131 | df->n_blocks_inverted = df_prune_to_subcfg (df->postorder_inverted, | |
1132 | df->n_blocks_inverted, | |
1133 | df->blocks_to_analyze); | |
e011eba9 | 1134 | BITMAP_FREE (current_all_blocks); |
1135 | } | |
1136 | else | |
1137 | { | |
1138 | everything = true; | |
1139 | df->blocks_to_analyze = current_all_blocks; | |
1140 | current_all_blocks = NULL; | |
1141 | } | |
1142 | ||
1143 | /* Skip over the DF_SCAN problem. */ | |
1144 | for (i = 1; i < df->num_problems_defined; i++) | |
3072d30e | 1145 | { |
1146 | struct dataflow *dflow = df->problems_in_order[i]; | |
1147 | if (dflow->solutions_dirty) | |
1148 | { | |
1149 | if (dflow->problem->dir == DF_FORWARD) | |
1150 | df_analyze_problem (dflow, | |
1151 | df->blocks_to_analyze, | |
1152 | df->postorder_inverted, | |
1153 | df->n_blocks_inverted); | |
1154 | else | |
1155 | df_analyze_problem (dflow, | |
1156 | df->blocks_to_analyze, | |
1157 | df->postorder, | |
1158 | df->n_blocks); | |
1159 | } | |
1160 | } | |
e011eba9 | 1161 | |
1162 | if (everything) | |
1163 | { | |
1164 | BITMAP_FREE (df->blocks_to_analyze); | |
1165 | df->blocks_to_analyze = NULL; | |
1166 | } | |
1167 | ||
3072d30e | 1168 | #ifdef DF_DEBUG_CFG |
1169 | df_set_clean_cfg (); | |
1170 | #endif | |
1171 | } | |
1172 | ||
1173 | ||
1174 | /* Return the number of basic blocks from the last call to df_analyze. */ | |
1175 | ||
1176 | int | |
1177 | df_get_n_blocks (enum df_flow_dir dir) | |
1178 | { | |
1179 | gcc_assert (dir != DF_NONE); | |
1180 | ||
1181 | if (dir == DF_FORWARD) | |
1182 | { | |
1183 | gcc_assert (df->postorder_inverted); | |
1184 | return df->n_blocks_inverted; | |
1185 | } | |
1186 | ||
1187 | gcc_assert (df->postorder); | |
1188 | return df->n_blocks; | |
1189 | } | |
1190 | ||
1191 | ||
1192 | /* Return a pointer to the array of basic blocks in the reverse postorder. | |
1193 | Depending on the direction of the dataflow problem, | |
1194 | it returns either the usual reverse postorder array | |
1195 | or the reverse postorder of inverted traversal. */ | |
1196 | int * | |
1197 | df_get_postorder (enum df_flow_dir dir) | |
1198 | { | |
1199 | gcc_assert (dir != DF_NONE); | |
1200 | ||
1201 | if (dir == DF_FORWARD) | |
1202 | { | |
1203 | gcc_assert (df->postorder_inverted); | |
1204 | return df->postorder_inverted; | |
1205 | } | |
1206 | gcc_assert (df->postorder); | |
1207 | return df->postorder; | |
e011eba9 | 1208 | } |
1209 | ||
3072d30e | 1210 | static struct df_problem user_problem; |
1211 | static struct dataflow user_dflow; | |
e011eba9 | 1212 | |
3072d30e | 1213 | /* Interface for calling iterative dataflow with user defined |
1214 | confluence and transfer functions. All that is necessary is to | |
1215 | supply DIR, a direction, CONF_FUN_0, a confluence function for | |
1216 | blocks with no logical preds (or NULL), CONF_FUN_N, the normal | |
1217 | confluence function, TRANS_FUN, the basic block transfer function, | |
1218 | and BLOCKS, the set of blocks to examine, POSTORDER the blocks in | |
1219 | postorder, and N_BLOCKS, the number of blocks in POSTORDER. */ | |
1220 | ||
1221 | void | |
1222 | df_simple_dataflow (enum df_flow_dir dir, | |
1223 | df_init_function init_fun, | |
1224 | df_confluence_function_0 con_fun_0, | |
1225 | df_confluence_function_n con_fun_n, | |
1226 | df_transfer_function trans_fun, | |
1227 | bitmap blocks, int * postorder, int n_blocks) | |
1228 | { | |
1229 | memset (&user_problem, 0, sizeof (struct df_problem)); | |
1230 | user_problem.dir = dir; | |
1231 | user_problem.init_fun = init_fun; | |
1232 | user_problem.con_fun_0 = con_fun_0; | |
1233 | user_problem.con_fun_n = con_fun_n; | |
1234 | user_problem.trans_fun = trans_fun; | |
1235 | user_dflow.problem = &user_problem; | |
1236 | df_worklist_dataflow (&user_dflow, blocks, postorder, n_blocks); | |
1237 | } | |
1238 | ||
1239 | ||
e011eba9 | 1240 | \f |
1241 | /*---------------------------------------------------------------------------- | |
1242 | Functions to support limited incremental change. | |
1243 | ----------------------------------------------------------------------------*/ | |
1244 | ||
1245 | ||
1246 | /* Get basic block info. */ | |
1247 | ||
1248 | static void * | |
1249 | df_get_bb_info (struct dataflow *dflow, unsigned int index) | |
1250 | { | |
3072d30e | 1251 | if (dflow->block_info == NULL) |
1252 | return NULL; | |
1253 | if (index >= dflow->block_info_size) | |
1254 | return NULL; | |
e011eba9 | 1255 | return (struct df_scan_bb_info *) dflow->block_info[index]; |
1256 | } | |
1257 | ||
1258 | ||
1259 | /* Set basic block info. */ | |
1260 | ||
1261 | static void | |
1262 | df_set_bb_info (struct dataflow *dflow, unsigned int index, | |
1263 | void *bb_info) | |
1264 | { | |
3072d30e | 1265 | gcc_assert (dflow->block_info); |
e011eba9 | 1266 | dflow->block_info[index] = bb_info; |
1267 | } | |
1268 | ||
1269 | ||
3072d30e | 1270 | /* Mark the solutions as being out of date. */ |
1271 | ||
1272 | void | |
1273 | df_mark_solutions_dirty (void) | |
1274 | { | |
1275 | if (df) | |
1276 | { | |
1277 | int p; | |
1278 | for (p = 1; p < df->num_problems_defined; p++) | |
1279 | df->problems_in_order[p]->solutions_dirty = true; | |
1280 | } | |
1281 | } | |
1282 | ||
1283 | ||
1284 | /* Return true if BB needs it's transfer functions recomputed. */ | |
1285 | ||
1286 | bool | |
1287 | df_get_bb_dirty (basic_block bb) | |
1288 | { | |
1289 | if (df && df_live) | |
1290 | return bitmap_bit_p (df_live->out_of_date_transfer_functions, bb->index); | |
1291 | else | |
1292 | return false; | |
1293 | } | |
1294 | ||
1295 | ||
1296 | /* Mark BB as needing it's transfer functions as being out of | |
1297 | date. */ | |
1298 | ||
1299 | void | |
1300 | df_set_bb_dirty (basic_block bb) | |
1301 | { | |
1302 | if (df) | |
1303 | { | |
1304 | int p; | |
1305 | for (p = 1; p < df->num_problems_defined; p++) | |
1306 | { | |
1307 | struct dataflow *dflow = df->problems_in_order[p]; | |
1308 | if (dflow->out_of_date_transfer_functions) | |
1309 | bitmap_set_bit (dflow->out_of_date_transfer_functions, bb->index); | |
1310 | } | |
1311 | df_mark_solutions_dirty (); | |
1312 | } | |
1313 | } | |
1314 | ||
1315 | ||
1316 | /* Clear the dirty bits. This is called from places that delete | |
1317 | blocks. */ | |
1318 | static void | |
1319 | df_clear_bb_dirty (basic_block bb) | |
1320 | { | |
1321 | int p; | |
1322 | for (p = 1; p < df->num_problems_defined; p++) | |
1323 | { | |
1324 | struct dataflow *dflow = df->problems_in_order[p]; | |
1325 | if (dflow->out_of_date_transfer_functions) | |
1326 | bitmap_clear_bit (dflow->out_of_date_transfer_functions, bb->index); | |
1327 | } | |
1328 | } | |
e011eba9 | 1329 | /* Called from the rtl_compact_blocks to reorganize the problems basic |
1330 | block info. */ | |
1331 | ||
1332 | void | |
3072d30e | 1333 | df_compact_blocks (void) |
e011eba9 | 1334 | { |
1335 | int i, p; | |
1336 | basic_block bb; | |
1337 | void **problem_temps; | |
3072d30e | 1338 | int size = last_basic_block * sizeof (void *); |
1339 | bitmap tmp = BITMAP_ALLOC (&df_bitmap_obstack); | |
e011eba9 | 1340 | problem_temps = xmalloc (size); |
1341 | ||
1342 | for (p = 0; p < df->num_problems_defined; p++) | |
1343 | { | |
1344 | struct dataflow *dflow = df->problems_in_order[p]; | |
3072d30e | 1345 | |
1346 | /* Need to reorganize the out_of_date_transfer_functions for the | |
1347 | dflow problem. */ | |
1348 | if (dflow->out_of_date_transfer_functions) | |
1349 | { | |
1350 | bitmap_copy (tmp, dflow->out_of_date_transfer_functions); | |
1351 | bitmap_clear (dflow->out_of_date_transfer_functions); | |
1352 | if (bitmap_bit_p (tmp, ENTRY_BLOCK)) | |
1353 | bitmap_set_bit (dflow->out_of_date_transfer_functions, ENTRY_BLOCK); | |
1354 | if (bitmap_bit_p (tmp, EXIT_BLOCK)) | |
1355 | bitmap_set_bit (dflow->out_of_date_transfer_functions, EXIT_BLOCK); | |
1356 | ||
1357 | i = NUM_FIXED_BLOCKS; | |
1358 | FOR_EACH_BB (bb) | |
1359 | { | |
1360 | if (bitmap_bit_p (tmp, bb->index)) | |
1361 | bitmap_set_bit (dflow->out_of_date_transfer_functions, i); | |
1362 | i++; | |
1363 | } | |
1364 | } | |
1365 | ||
1366 | /* Now shuffle the block info for the problem. */ | |
1c1a6437 | 1367 | if (dflow->problem->free_bb_fun) |
e011eba9 | 1368 | { |
1369 | df_grow_bb_info (dflow); | |
1370 | memcpy (problem_temps, dflow->block_info, size); | |
1371 | ||
1372 | /* Copy the bb info from the problem tmps to the proper | |
1373 | place in the block_info vector. Null out the copied | |
3072d30e | 1374 | item. The entry and exit blocks never move. */ |
e011eba9 | 1375 | i = NUM_FIXED_BLOCKS; |
1376 | FOR_EACH_BB (bb) | |
1377 | { | |
1378 | df_set_bb_info (dflow, i, problem_temps[bb->index]); | |
1379 | problem_temps[bb->index] = NULL; | |
1380 | i++; | |
1381 | } | |
1382 | memset (dflow->block_info + i, 0, | |
1383 | (last_basic_block - i) *sizeof (void *)); | |
1384 | ||
1385 | /* Free any block infos that were not copied (and NULLed). | |
1386 | These are from orphaned blocks. */ | |
1387 | for (i = NUM_FIXED_BLOCKS; i < last_basic_block; i++) | |
1388 | { | |
d0802b39 | 1389 | basic_block bb = BASIC_BLOCK (i); |
1390 | if (problem_temps[i] && bb) | |
1c1a6437 | 1391 | dflow->problem->free_bb_fun |
3072d30e | 1392 | (bb, problem_temps[i]); |
e011eba9 | 1393 | } |
1394 | } | |
1395 | } | |
1396 | ||
3072d30e | 1397 | /* Shuffle the bits in the basic_block indexed arrays. */ |
1398 | ||
1399 | if (df->blocks_to_analyze) | |
1400 | { | |
1401 | if (bitmap_bit_p (tmp, ENTRY_BLOCK)) | |
1402 | bitmap_set_bit (df->blocks_to_analyze, ENTRY_BLOCK); | |
1403 | if (bitmap_bit_p (tmp, EXIT_BLOCK)) | |
1404 | bitmap_set_bit (df->blocks_to_analyze, EXIT_BLOCK); | |
1405 | bitmap_copy (tmp, df->blocks_to_analyze); | |
1406 | bitmap_clear (df->blocks_to_analyze); | |
1407 | i = NUM_FIXED_BLOCKS; | |
1408 | FOR_EACH_BB (bb) | |
1409 | { | |
1410 | if (bitmap_bit_p (tmp, bb->index)) | |
1411 | bitmap_set_bit (df->blocks_to_analyze, i); | |
1412 | i++; | |
1413 | } | |
1414 | } | |
1415 | ||
1416 | BITMAP_FREE (tmp); | |
1417 | ||
e011eba9 | 1418 | free (problem_temps); |
1419 | ||
1420 | i = NUM_FIXED_BLOCKS; | |
1421 | FOR_EACH_BB (bb) | |
1422 | { | |
a9b9dcf4 | 1423 | SET_BASIC_BLOCK (i, bb); |
e011eba9 | 1424 | bb->index = i; |
1425 | i++; | |
1426 | } | |
1427 | ||
1428 | gcc_assert (i == n_basic_blocks); | |
1429 | ||
1430 | for (; i < last_basic_block; i++) | |
a9b9dcf4 | 1431 | SET_BASIC_BLOCK (i, NULL); |
3072d30e | 1432 | |
1433 | #ifdef DF_DEBUG_CFG | |
1434 | if (!df_lr->solutions_dirty) | |
1435 | df_set_clean_cfg (); | |
1436 | #endif | |
e011eba9 | 1437 | } |
1438 | ||
1439 | ||
3072d30e | 1440 | /* Shove NEW_BLOCK in at OLD_INDEX. Called from ifcvt to hack a |
e011eba9 | 1441 | block. There is no excuse for people to do this kind of thing. */ |
1442 | ||
1443 | void | |
3072d30e | 1444 | df_bb_replace (int old_index, basic_block new_block) |
e011eba9 | 1445 | { |
3072d30e | 1446 | int new_block_index = new_block->index; |
e011eba9 | 1447 | int p; |
1448 | ||
3072d30e | 1449 | if (dump_file) |
1450 | fprintf (dump_file, "shoving block %d into %d\n", new_block_index, old_index); | |
1451 | ||
1452 | gcc_assert (df); | |
1453 | gcc_assert (BASIC_BLOCK (old_index) == NULL); | |
1454 | ||
e011eba9 | 1455 | for (p = 0; p < df->num_problems_defined; p++) |
1456 | { | |
1457 | struct dataflow *dflow = df->problems_in_order[p]; | |
1458 | if (dflow->block_info) | |
1459 | { | |
e011eba9 | 1460 | df_grow_bb_info (dflow); |
3072d30e | 1461 | gcc_assert (df_get_bb_info (dflow, old_index) == NULL); |
e011eba9 | 1462 | df_set_bb_info (dflow, old_index, |
3072d30e | 1463 | df_get_bb_info (dflow, new_block_index)); |
e011eba9 | 1464 | } |
1465 | } | |
1466 | ||
3072d30e | 1467 | df_clear_bb_dirty (new_block); |
a9b9dcf4 | 1468 | SET_BASIC_BLOCK (old_index, new_block); |
e011eba9 | 1469 | new_block->index = old_index; |
3072d30e | 1470 | df_set_bb_dirty (BASIC_BLOCK (old_index)); |
1471 | SET_BASIC_BLOCK (new_block_index, NULL); | |
1472 | } | |
1473 | ||
1474 | ||
1475 | /* Free all of the per basic block dataflow from all of the problems. | |
1476 | This is typically called before a basic block is deleted and the | |
1477 | problem will be reanalyzed. */ | |
1478 | ||
1479 | void | |
1480 | df_bb_delete (int bb_index) | |
1481 | { | |
1482 | basic_block bb = BASIC_BLOCK (bb_index); | |
1483 | int i; | |
1484 | ||
1485 | if (!df) | |
1486 | return; | |
1487 | ||
1488 | for (i = 0; i < df->num_problems_defined; i++) | |
1489 | { | |
1490 | struct dataflow *dflow = df->problems_in_order[i]; | |
1491 | if (dflow->problem->free_bb_fun) | |
1492 | { | |
1493 | void *bb_info = df_get_bb_info (dflow, bb_index); | |
1494 | if (bb_info) | |
1495 | { | |
1496 | dflow->problem->free_bb_fun (bb, bb_info); | |
1497 | df_set_bb_info (dflow, bb_index, NULL); | |
1498 | } | |
1499 | } | |
1500 | } | |
1501 | df_clear_bb_dirty (bb); | |
1502 | df_mark_solutions_dirty (); | |
1503 | } | |
1504 | ||
1505 | ||
1506 | /* Verify that there is a place for everything and everything is in | |
1507 | its place. This is too expensive to run after every pass in the | |
1508 | mainline. However this is an excellent debugging tool if the | |
6dfdc153 | 1509 | dataflow information is not being updated properly. You can just |
3072d30e | 1510 | sprinkle calls in until you find the place that is changing an |
1511 | underlying structure without calling the proper updating | |
bef304b8 | 1512 | routine. */ |
3072d30e | 1513 | |
1514 | void | |
1515 | df_verify (void) | |
1516 | { | |
1517 | df_scan_verify (); | |
314966f4 | 1518 | #ifdef ENABLE_DF_CHECKING |
3072d30e | 1519 | df_lr_verify_transfer_functions (); |
1520 | if (df_live) | |
1521 | df_live_verify_transfer_functions (); | |
314966f4 | 1522 | #endif |
3072d30e | 1523 | } |
1524 | ||
1525 | #ifdef DF_DEBUG_CFG | |
1526 | ||
1527 | /* Compute an array of ints that describes the cfg. This can be used | |
1528 | to discover places where the cfg is modified by the appropriate | |
1529 | calls have not been made to the keep df informed. The internals of | |
1530 | this are unexciting, the key is that two instances of this can be | |
1531 | compared to see if any changes have been made to the cfg. */ | |
1532 | ||
1533 | static int * | |
1534 | df_compute_cfg_image (void) | |
1535 | { | |
1536 | basic_block bb; | |
1537 | int size = 2 + (2 * n_basic_blocks); | |
1538 | int i; | |
1539 | int * map; | |
1540 | ||
1541 | FOR_ALL_BB (bb) | |
1542 | { | |
1543 | size += EDGE_COUNT (bb->succs); | |
1544 | } | |
1545 | ||
1546 | map = XNEWVEC (int, size); | |
1547 | map[0] = size; | |
1548 | i = 1; | |
1549 | FOR_ALL_BB (bb) | |
1550 | { | |
1551 | edge_iterator ei; | |
1552 | edge e; | |
1553 | ||
1554 | map[i++] = bb->index; | |
1555 | FOR_EACH_EDGE (e, ei, bb->succs) | |
1556 | map[i++] = e->dest->index; | |
1557 | map[i++] = -1; | |
1558 | } | |
1559 | map[i] = -1; | |
1560 | return map; | |
1561 | } | |
1562 | ||
1563 | static int *saved_cfg = NULL; | |
1564 | ||
1565 | ||
1566 | /* This function compares the saved version of the cfg with the | |
1567 | current cfg and aborts if the two are identical. The function | |
1568 | silently returns if the cfg has been marked as dirty or the two are | |
1569 | the same. */ | |
1570 | ||
1571 | void | |
1572 | df_check_cfg_clean (void) | |
1573 | { | |
1574 | int *new_map; | |
1575 | ||
1576 | if (!df) | |
1577 | return; | |
1578 | ||
1579 | if (df_lr->solutions_dirty) | |
1580 | return; | |
1581 | ||
1582 | if (saved_cfg == NULL) | |
1583 | return; | |
1584 | ||
1585 | new_map = df_compute_cfg_image (); | |
1586 | gcc_assert (memcmp (saved_cfg, new_map, saved_cfg[0] * sizeof (int)) == 0); | |
1587 | free (new_map); | |
e011eba9 | 1588 | } |
1589 | ||
3072d30e | 1590 | |
1591 | /* This function builds a cfg fingerprint and squirrels it away in | |
1592 | saved_cfg. */ | |
1593 | ||
1594 | static void | |
1595 | df_set_clean_cfg (void) | |
1596 | { | |
1597 | if (saved_cfg) | |
1598 | free (saved_cfg); | |
1599 | saved_cfg = df_compute_cfg_image (); | |
1600 | } | |
1601 | ||
1602 | #endif /* DF_DEBUG_CFG */ | |
e011eba9 | 1603 | /*---------------------------------------------------------------------------- |
1604 | PUBLIC INTERFACES TO QUERY INFORMATION. | |
1605 | ----------------------------------------------------------------------------*/ | |
1606 | ||
1607 | ||
e011eba9 | 1608 | /* Return first def of REGNO within BB. */ |
1609 | ||
1610 | struct df_ref * | |
3072d30e | 1611 | df_bb_regno_first_def_find (basic_block bb, unsigned int regno) |
e011eba9 | 1612 | { |
1613 | rtx insn; | |
3072d30e | 1614 | struct df_ref **def_rec; |
6151bbc3 | 1615 | unsigned int uid; |
e011eba9 | 1616 | |
1617 | FOR_BB_INSNS (bb, insn) | |
1618 | { | |
6151bbc3 | 1619 | if (!INSN_P (insn)) |
1620 | continue; | |
1621 | ||
1622 | uid = INSN_UID (insn); | |
3072d30e | 1623 | for (def_rec = DF_INSN_UID_DEFS (uid); *def_rec; def_rec++) |
1624 | { | |
1625 | struct df_ref *def = *def_rec; | |
1626 | if (DF_REF_REGNO (def) == regno) | |
1627 | return def; | |
1628 | } | |
e011eba9 | 1629 | } |
1630 | return NULL; | |
1631 | } | |
1632 | ||
1633 | ||
1634 | /* Return last def of REGNO within BB. */ | |
1635 | ||
1636 | struct df_ref * | |
3072d30e | 1637 | df_bb_regno_last_def_find (basic_block bb, unsigned int regno) |
e011eba9 | 1638 | { |
1639 | rtx insn; | |
3072d30e | 1640 | struct df_ref **def_rec; |
6151bbc3 | 1641 | unsigned int uid; |
e011eba9 | 1642 | |
1643 | FOR_BB_INSNS_REVERSE (bb, insn) | |
1644 | { | |
6151bbc3 | 1645 | if (!INSN_P (insn)) |
1646 | continue; | |
e011eba9 | 1647 | |
6151bbc3 | 1648 | uid = INSN_UID (insn); |
3072d30e | 1649 | for (def_rec = DF_INSN_UID_DEFS (uid); *def_rec; def_rec++) |
1650 | { | |
1651 | struct df_ref *def = *def_rec; | |
1652 | if (DF_REF_REGNO (def) == regno) | |
1653 | return def; | |
1654 | } | |
e011eba9 | 1655 | } |
1656 | ||
1657 | return NULL; | |
1658 | } | |
1659 | ||
e011eba9 | 1660 | /* Finds the reference corresponding to the definition of REG in INSN. |
1661 | DF is the dataflow object. */ | |
1662 | ||
1663 | struct df_ref * | |
3072d30e | 1664 | df_find_def (rtx insn, rtx reg) |
e011eba9 | 1665 | { |
1666 | unsigned int uid; | |
3072d30e | 1667 | struct df_ref **def_rec; |
e011eba9 | 1668 | |
1669 | if (GET_CODE (reg) == SUBREG) | |
1670 | reg = SUBREG_REG (reg); | |
1671 | gcc_assert (REG_P (reg)); | |
1672 | ||
1673 | uid = INSN_UID (insn); | |
3072d30e | 1674 | for (def_rec = DF_INSN_UID_DEFS (uid); *def_rec; def_rec++) |
1675 | { | |
1676 | struct df_ref *def = *def_rec; | |
1677 | if (rtx_equal_p (DF_REF_REAL_REG (def), reg)) | |
1678 | return def; | |
1679 | } | |
e011eba9 | 1680 | |
1681 | return NULL; | |
1682 | } | |
1683 | ||
1684 | ||
1685 | /* Return true if REG is defined in INSN, zero otherwise. */ | |
1686 | ||
1687 | bool | |
3072d30e | 1688 | df_reg_defined (rtx insn, rtx reg) |
e011eba9 | 1689 | { |
3072d30e | 1690 | return df_find_def (insn, reg) != NULL; |
e011eba9 | 1691 | } |
1692 | ||
1693 | ||
1694 | /* Finds the reference corresponding to the use of REG in INSN. | |
1695 | DF is the dataflow object. */ | |
1696 | ||
1697 | struct df_ref * | |
3072d30e | 1698 | df_find_use (rtx insn, rtx reg) |
e011eba9 | 1699 | { |
1700 | unsigned int uid; | |
3072d30e | 1701 | struct df_ref **use_rec; |
e011eba9 | 1702 | |
1703 | if (GET_CODE (reg) == SUBREG) | |
1704 | reg = SUBREG_REG (reg); | |
1705 | gcc_assert (REG_P (reg)); | |
1706 | ||
1707 | uid = INSN_UID (insn); | |
3072d30e | 1708 | for (use_rec = DF_INSN_UID_USES (uid); *use_rec; use_rec++) |
1709 | { | |
1710 | struct df_ref *use = *use_rec; | |
1711 | if (rtx_equal_p (DF_REF_REAL_REG (use), reg)) | |
1712 | return use; | |
1713 | } | |
1714 | if (df->changeable_flags & DF_EQ_NOTES) | |
1715 | for (use_rec = DF_INSN_UID_EQ_USES (uid); *use_rec; use_rec++) | |
1716 | { | |
1717 | struct df_ref *use = *use_rec; | |
1718 | if (rtx_equal_p (DF_REF_REAL_REG (use), reg)) | |
1719 | return use; | |
1720 | } | |
e011eba9 | 1721 | return NULL; |
1722 | } | |
1723 | ||
1724 | ||
1725 | /* Return true if REG is referenced in INSN, zero otherwise. */ | |
1726 | ||
1727 | bool | |
3072d30e | 1728 | df_reg_used (rtx insn, rtx reg) |
e011eba9 | 1729 | { |
3072d30e | 1730 | return df_find_use (insn, reg) != NULL; |
e011eba9 | 1731 | } |
1732 | ||
1733 | \f | |
1734 | /*---------------------------------------------------------------------------- | |
1735 | Debugging and printing functions. | |
1736 | ----------------------------------------------------------------------------*/ | |
1737 | ||
3072d30e | 1738 | |
1739 | /* Write information about registers and basic blocks into FILE. | |
1740 | This is part of making a debugging dump. */ | |
1741 | ||
1742 | void | |
1743 | df_print_regset (FILE *file, bitmap r) | |
1744 | { | |
1745 | unsigned int i; | |
1746 | bitmap_iterator bi; | |
1747 | ||
1748 | if (r == NULL) | |
1749 | fputs (" (nil)", file); | |
1750 | else | |
1751 | { | |
1752 | EXECUTE_IF_SET_IN_BITMAP (r, 0, i, bi) | |
1753 | { | |
1754 | fprintf (file, " %d", i); | |
1755 | if (i < FIRST_PSEUDO_REGISTER) | |
1756 | fprintf (file, " [%s]", reg_names[i]); | |
1757 | } | |
1758 | } | |
1759 | fprintf (file, "\n"); | |
1760 | } | |
1761 | ||
1762 | ||
e011eba9 | 1763 | /* Dump dataflow info. */ |
774f8797 | 1764 | |
e011eba9 | 1765 | void |
3072d30e | 1766 | df_dump (FILE *file) |
1767 | { | |
1768 | basic_block bb; | |
1769 | df_dump_start (file); | |
1770 | ||
1771 | FOR_ALL_BB (bb) | |
1772 | { | |
1773 | df_print_bb_index (bb, file); | |
1774 | df_dump_top (bb, file); | |
1775 | df_dump_bottom (bb, file); | |
1776 | } | |
1777 | ||
1778 | fprintf (file, "\n"); | |
1779 | } | |
1780 | ||
1781 | ||
774f8797 | 1782 | /* Dump dataflow info for df->blocks_to_analyze. */ |
1783 | ||
1784 | void | |
1785 | df_dump_region (FILE *file) | |
1786 | { | |
1787 | if (df->blocks_to_analyze) | |
1788 | { | |
1789 | bitmap_iterator bi; | |
1790 | unsigned int bb_index; | |
1791 | ||
1792 | fprintf (file, "\n\nstarting region dump\n"); | |
1793 | df_dump_start (file); | |
1794 | ||
1795 | EXECUTE_IF_SET_IN_BITMAP (df->blocks_to_analyze, 0, bb_index, bi) | |
1796 | { | |
1797 | basic_block bb = BASIC_BLOCK (bb_index); | |
1798 | ||
1799 | df_print_bb_index (bb, file); | |
1800 | df_dump_top (bb, file); | |
1801 | df_dump_bottom (bb, file); | |
1802 | } | |
1803 | fprintf (file, "\n"); | |
1804 | } | |
1805 | else | |
1806 | df_dump (file); | |
1807 | } | |
1808 | ||
1809 | ||
3072d30e | 1810 | /* Dump the introductory information for each problem defined. */ |
1811 | ||
1812 | void | |
1813 | df_dump_start (FILE *file) | |
e011eba9 | 1814 | { |
1815 | int i; | |
1816 | ||
3e6933a8 | 1817 | if (!df || !file) |
e011eba9 | 1818 | return; |
1819 | ||
1820 | fprintf (file, "\n\n%s\n", current_function_name ()); | |
1821 | fprintf (file, "\nDataflow summary:\n"); | |
3072d30e | 1822 | if (df->blocks_to_analyze) |
1823 | fprintf (file, "def_info->table_size = %d, use_info->table_size = %d\n", | |
1824 | DF_DEFS_TABLE_SIZE (), DF_USES_TABLE_SIZE ()); | |
e011eba9 | 1825 | |
1826 | for (i = 0; i < df->num_problems_defined; i++) | |
3072d30e | 1827 | { |
1828 | struct dataflow *dflow = df->problems_in_order[i]; | |
1829 | if (dflow->computed) | |
1830 | { | |
1831 | df_dump_problem_function fun = dflow->problem->dump_start_fun; | |
1832 | if (fun) | |
1833 | fun(file); | |
1834 | } | |
1835 | } | |
1836 | } | |
e011eba9 | 1837 | |
3072d30e | 1838 | |
1839 | /* Dump the top of the block information for BB. */ | |
1840 | ||
1841 | void | |
1842 | df_dump_top (basic_block bb, FILE *file) | |
1843 | { | |
1844 | int i; | |
1845 | ||
1846 | if (!df || !file) | |
1847 | return; | |
1848 | ||
1849 | for (i = 0; i < df->num_problems_defined; i++) | |
1850 | { | |
1851 | struct dataflow *dflow = df->problems_in_order[i]; | |
1852 | if (dflow->computed) | |
1853 | { | |
1854 | df_dump_bb_problem_function bbfun = dflow->problem->dump_top_fun; | |
1855 | if (bbfun) | |
1856 | bbfun (bb, file); | |
1857 | } | |
1858 | } | |
1859 | } | |
1860 | ||
1861 | ||
1862 | /* Dump the bottom of the block information for BB. */ | |
1863 | ||
1864 | void | |
1865 | df_dump_bottom (basic_block bb, FILE *file) | |
1866 | { | |
1867 | int i; | |
1868 | ||
1869 | if (!df || !file) | |
1870 | return; | |
1871 | ||
1872 | for (i = 0; i < df->num_problems_defined; i++) | |
1873 | { | |
1874 | struct dataflow *dflow = df->problems_in_order[i]; | |
1875 | if (dflow->computed) | |
1876 | { | |
1877 | df_dump_bb_problem_function bbfun = dflow->problem->dump_bottom_fun; | |
1878 | if (bbfun) | |
1879 | bbfun (bb, file); | |
1880 | } | |
1881 | } | |
e011eba9 | 1882 | } |
1883 | ||
1884 | ||
1885 | void | |
3072d30e | 1886 | df_refs_chain_dump (struct df_ref **ref_rec, bool follow_chain, FILE *file) |
e011eba9 | 1887 | { |
1888 | fprintf (file, "{ "); | |
3072d30e | 1889 | while (*ref_rec) |
e011eba9 | 1890 | { |
3072d30e | 1891 | struct df_ref *ref = *ref_rec; |
1892 | fprintf (file, "%c%d(%d)", | |
1893 | DF_REF_REG_DEF_P (ref) ? 'd' : (DF_REF_FLAGS (ref) & DF_REF_IN_NOTE) ? 'e' : 'u', | |
e011eba9 | 1894 | DF_REF_ID (ref), |
1895 | DF_REF_REGNO (ref)); | |
1896 | if (follow_chain) | |
3e6933a8 | 1897 | df_chain_dump (DF_REF_CHAIN (ref), file); |
3072d30e | 1898 | ref_rec++; |
e011eba9 | 1899 | } |
1900 | fprintf (file, "}"); | |
1901 | } | |
1902 | ||
1903 | ||
1904 | /* Dump either a ref-def or reg-use chain. */ | |
1905 | ||
1906 | void | |
3072d30e | 1907 | df_regs_chain_dump (struct df_ref *ref, FILE *file) |
e011eba9 | 1908 | { |
1909 | fprintf (file, "{ "); | |
1910 | while (ref) | |
1911 | { | |
1912 | fprintf (file, "%c%d(%d) ", | |
1913 | DF_REF_REG_DEF_P (ref) ? 'd' : 'u', | |
1914 | DF_REF_ID (ref), | |
1915 | DF_REF_REGNO (ref)); | |
1916 | ref = ref->next_reg; | |
1917 | } | |
1918 | fprintf (file, "}"); | |
1919 | } | |
1920 | ||
1921 | ||
3e6933a8 | 1922 | static void |
3072d30e | 1923 | df_mws_dump (struct df_mw_hardreg **mws, FILE *file) |
e011eba9 | 1924 | { |
3072d30e | 1925 | while (*mws) |
3e6933a8 | 1926 | { |
3072d30e | 1927 | fprintf (file, "mw %c r[%d..%d]\n", |
1928 | ((*mws)->type == DF_REF_REG_DEF) ? 'd' : 'u', | |
1929 | (*mws)->start_regno, (*mws)->end_regno); | |
1930 | mws++; | |
3e6933a8 | 1931 | } |
1932 | } | |
1933 | ||
1934 | ||
1935 | static void | |
3072d30e | 1936 | df_insn_uid_debug (unsigned int uid, |
3e6933a8 | 1937 | bool follow_chain, FILE *file) |
1938 | { | |
3072d30e | 1939 | fprintf (file, "insn %d luid %d", |
1940 | uid, DF_INSN_UID_LUID (uid)); | |
e011eba9 | 1941 | |
3072d30e | 1942 | if (DF_INSN_UID_DEFS (uid)) |
3e6933a8 | 1943 | { |
1944 | fprintf (file, " defs "); | |
3072d30e | 1945 | df_refs_chain_dump (DF_INSN_UID_DEFS (uid), follow_chain, file); |
3e6933a8 | 1946 | } |
1947 | ||
3072d30e | 1948 | if (DF_INSN_UID_USES (uid)) |
3e6933a8 | 1949 | { |
1950 | fprintf (file, " uses "); | |
3072d30e | 1951 | df_refs_chain_dump (DF_INSN_UID_USES (uid), follow_chain, file); |
1952 | } | |
1953 | ||
1954 | if (DF_INSN_UID_EQ_USES (uid)) | |
1955 | { | |
1956 | fprintf (file, " eq uses "); | |
1957 | df_refs_chain_dump (DF_INSN_UID_EQ_USES (uid), follow_chain, file); | |
3e6933a8 | 1958 | } |
1959 | ||
3072d30e | 1960 | if (DF_INSN_UID_MWS (uid)) |
3e6933a8 | 1961 | { |
1962 | fprintf (file, " mws "); | |
3072d30e | 1963 | df_mws_dump (DF_INSN_UID_MWS (uid), file); |
3e6933a8 | 1964 | } |
e011eba9 | 1965 | fprintf (file, "\n"); |
1966 | } | |
1967 | ||
3e6933a8 | 1968 | |
1969 | void | |
3072d30e | 1970 | df_insn_debug (rtx insn, bool follow_chain, FILE *file) |
3e6933a8 | 1971 | { |
3072d30e | 1972 | df_insn_uid_debug (INSN_UID (insn), follow_chain, file); |
3e6933a8 | 1973 | } |
1974 | ||
e011eba9 | 1975 | void |
3072d30e | 1976 | df_insn_debug_regno (rtx insn, FILE *file) |
e011eba9 | 1977 | { |
3072d30e | 1978 | unsigned int uid = INSN_UID(insn); |
e011eba9 | 1979 | |
1980 | fprintf (file, "insn %d bb %d luid %d defs ", | |
3072d30e | 1981 | uid, BLOCK_FOR_INSN (insn)->index, DF_INSN_LUID (insn)); |
1982 | df_refs_chain_dump (DF_INSN_UID_DEFS (uid), false, file); | |
e011eba9 | 1983 | |
1984 | fprintf (file, " uses "); | |
3072d30e | 1985 | df_refs_chain_dump (DF_INSN_UID_USES (uid), false, file); |
1986 | ||
1987 | fprintf (file, " eq_uses "); | |
1988 | df_refs_chain_dump (DF_INSN_UID_EQ_USES (uid), false, file); | |
e011eba9 | 1989 | fprintf (file, "\n"); |
1990 | } | |
1991 | ||
1992 | void | |
3072d30e | 1993 | df_regno_debug (unsigned int regno, FILE *file) |
e011eba9 | 1994 | { |
1995 | fprintf (file, "reg %d defs ", regno); | |
3072d30e | 1996 | df_regs_chain_dump (DF_REG_DEF_CHAIN (regno), file); |
e011eba9 | 1997 | fprintf (file, " uses "); |
3072d30e | 1998 | df_regs_chain_dump (DF_REG_USE_CHAIN (regno), file); |
1999 | fprintf (file, " eq_uses "); | |
2000 | df_regs_chain_dump (DF_REG_EQ_USE_CHAIN (regno), file); | |
e011eba9 | 2001 | fprintf (file, "\n"); |
2002 | } | |
2003 | ||
2004 | ||
2005 | void | |
3e6933a8 | 2006 | df_ref_debug (struct df_ref *ref, FILE *file) |
e011eba9 | 2007 | { |
2008 | fprintf (file, "%c%d ", | |
2009 | DF_REF_REG_DEF_P (ref) ? 'd' : 'u', | |
2010 | DF_REF_ID (ref)); | |
3072d30e | 2011 | fprintf (file, "reg %d bb %d insn %d flag 0x%x type 0x%x ", |
e011eba9 | 2012 | DF_REF_REGNO (ref), |
2013 | DF_REF_BBNO (ref), | |
3e6933a8 | 2014 | DF_REF_INSN (ref) ? INSN_UID (DF_REF_INSN (ref)) : -1, |
3072d30e | 2015 | DF_REF_FLAGS (ref), |
2016 | DF_REF_TYPE (ref)); | |
2017 | if (DF_REF_LOC (ref)) | |
2018 | fprintf (file, "loc %p(%p) chain ", (void *)DF_REF_LOC (ref), (void *)*DF_REF_LOC (ref)); | |
2019 | else | |
2020 | fprintf (file, "chain "); | |
3e6933a8 | 2021 | df_chain_dump (DF_REF_CHAIN (ref), file); |
e011eba9 | 2022 | fprintf (file, "\n"); |
2023 | } | |
2024 | \f | |
2025 | /* Functions for debugging from GDB. */ | |
2026 | ||
2027 | void | |
2028 | debug_df_insn (rtx insn) | |
2029 | { | |
3072d30e | 2030 | df_insn_debug (insn, true, stderr); |
e011eba9 | 2031 | debug_rtx (insn); |
2032 | } | |
2033 | ||
2034 | ||
2035 | void | |
2036 | debug_df_reg (rtx reg) | |
2037 | { | |
3072d30e | 2038 | df_regno_debug (REGNO (reg), stderr); |
e011eba9 | 2039 | } |
2040 | ||
2041 | ||
2042 | void | |
2043 | debug_df_regno (unsigned int regno) | |
2044 | { | |
3072d30e | 2045 | df_regno_debug (regno, stderr); |
e011eba9 | 2046 | } |
2047 | ||
2048 | ||
2049 | void | |
2050 | debug_df_ref (struct df_ref *ref) | |
2051 | { | |
3e6933a8 | 2052 | df_ref_debug (ref, stderr); |
e011eba9 | 2053 | } |
2054 | ||
2055 | ||
2056 | void | |
2057 | debug_df_defno (unsigned int defno) | |
2058 | { | |
3072d30e | 2059 | df_ref_debug (DF_DEFS_GET (defno), stderr); |
e011eba9 | 2060 | } |
2061 | ||
2062 | ||
2063 | void | |
2064 | debug_df_useno (unsigned int defno) | |
2065 | { | |
3072d30e | 2066 | df_ref_debug (DF_USES_GET (defno), stderr); |
e011eba9 | 2067 | } |
2068 | ||
2069 | ||
2070 | void | |
2071 | debug_df_chain (struct df_link *link) | |
2072 | { | |
3e6933a8 | 2073 | df_chain_dump (link, stderr); |
e011eba9 | 2074 | fputc ('\n', stderr); |
2075 | } |