1/* Allocation for dataflow support routines.
2 Copyright (C) 1999-2017 Free Software Foundation, Inc.
3 Originally contributed by Michael P. Hayes
4 (m.hayes@elec.canterbury.ac.nz, mhayes@redhat.com)
5 Major rewrite contributed by Danny Berlin (dberlin@dberlin.org)
6 and Kenneth Zadeck (zadeck@naturalbridge.com).
7
8This file is part of GCC.
9
10GCC is free software; you can redistribute it and/or modify it under
11the terms of the GNU General Public License as published by the Free
12Software Foundation; either version 3, or (at your option) any later
13version.
14
15GCC is distributed in the hope that it will be useful, but WITHOUT ANY
16WARRANTY; without even the implied warranty of MERCHANTABILITY or
17FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
18for more details.
19
20You should have received a copy of the GNU General Public License
21along with GCC; see the file COPYING3. If not see
22<http://www.gnu.org/licenses/>. */
23
24/*
25OVERVIEW:
26
27The files in this collection (df*.c,df.h) provide a general framework
28for solving dataflow problems. The global dataflow is performed using
29a good implementation of iterative dataflow analysis.
30
31The file df-problems.c provides problem instance for the most common
32dataflow problems: reaching defs, upward exposed uses, live variables,
33uninitialized variables, def-use chains, and use-def chains. However,
34the interface allows other dataflow problems to be defined as well.
35
36Dataflow analysis is available in most of the rtl backend (the parts
37between pass_df_initialize and pass_df_finish). It is quite likely
38that these boundaries will be expanded in the future. The only
39requirement is that there be a correct control flow graph.
40
41There are three variations of the live variable problem that are
42available whenever dataflow is available. The LR problem finds the
43areas that can reach a use of a variable, the UR problems finds the
44areas that can be reached from a definition of a variable. The LIVE
45problem finds the intersection of these two areas.
46
47There are several optional problems. These can be enabled when they
48are needed and disabled when they are not needed.
49
50Dataflow problems are generally solved in three layers. The bottom
51layer is called scanning where a data structure is built for each rtl
52insn that describes the set of defs and uses of that insn. Scanning
53is generally kept up to date, i.e. as the insns changes, the scanned
54version of that insn changes also. There are various mechanisms for
55making this happen and are described in the INCREMENTAL SCANNING
56section.
57
58In the middle layer, basic blocks are scanned to produce transfer
59functions which describe the effects of that block on the global
60dataflow solution. The transfer functions are only rebuilt if the
61some instruction within the block has changed.
62
63The top layer is the dataflow solution itself. The dataflow solution
64is computed by using an efficient iterative solver and the transfer
65functions. The dataflow solution must be recomputed whenever the
66control changes or if one of the transfer function changes.
67
68
69USAGE:
70
71Here is an example of using the dataflow routines.
72
73 df_[chain,live,note,rd]_add_problem (flags);
74
75 df_set_blocks (blocks);
76
77 df_analyze ();
78
79 df_dump (stderr);
80
81 df_finish_pass (false);
82
83DF_[chain,live,note,rd]_ADD_PROBLEM adds a problem, defined by an
84instance to struct df_problem, to the set of problems solved in this
85instance of df. All calls to add a problem for a given instance of df
86must occur before the first call to DF_ANALYZE.
87
88Problems can be dependent on other problems. For instance, solving
89def-use or use-def chains is dependent on solving reaching
90definitions. As long as these dependencies are listed in the problem
91definition, the order of adding the problems is not material.
92Otherwise, the problems will be solved in the order of calls to
93df_add_problem. Note that it is not necessary to have a problem. In
94that case, df will just be used to do the scanning.
95
96
97
98DF_SET_BLOCKS is an optional call used to define a region of the
99function on which the analysis will be performed. The normal case is
100to analyze the entire function and no call to df_set_blocks is made.
101DF_SET_BLOCKS only effects the blocks that are effected when computing
102the transfer functions and final solution. The insn level information
103is always kept up to date.
104
105When a subset is given, the analysis behaves as if the function only
106contains those blocks and any edges that occur directly between the
107blocks in the set. Care should be taken to call df_set_blocks right
108before the call to analyze in order to eliminate the possibility that
109optimizations that reorder blocks invalidate the bitvector.
110
111DF_ANALYZE causes all of the defined problems to be (re)solved. When
112DF_ANALYZE is completes, the IN and OUT sets for each basic block
113contain the computer information. The DF_*_BB_INFO macros can be used
114to access these bitvectors. All deferred rescannings are down before
115the transfer functions are recomputed.
116
117DF_DUMP can then be called to dump the information produce to some
118file. This calls DF_DUMP_START, to print the information that is not
119basic block specific, and then calls DF_DUMP_TOP and DF_DUMP_BOTTOM
120for each block to print the basic specific information. These parts
121can all be called separately as part of a larger dump function.
122
123
124DF_FINISH_PASS causes df_remove_problem to be called on all of the
125optional problems. It also causes any insns whose scanning has been
126deferred to be rescanned as well as clears all of the changeable flags.
127Setting the pass manager TODO_df_finish flag causes this function to
128be run. However, the pass manager will call df_finish_pass AFTER the
129pass dumping has been done, so if you want to see the results of the
130optional problems in the pass dumps, use the TODO flag rather than
131calling the function yourself.
132
133INCREMENTAL SCANNING
134
135There are four ways of doing the incremental scanning:
136
1371) Immediate rescanning - Calls to df_insn_rescan, df_notes_rescan,
138 df_bb_delete, df_insn_change_bb have been added to most of
139 the low level service functions that maintain the cfg and change
140 rtl. Calling and of these routines many cause some number of insns
141 to be rescanned.
142
143 For most modern rtl passes, this is certainly the easiest way to
144 manage rescanning the insns. This technique also has the advantage
145 that the scanning information is always correct and can be relied
146 upon even after changes have been made to the instructions. This
147 technique is contra indicated in several cases:
148
149 a) If def-use chains OR use-def chains (but not both) are built,
150 using this is SIMPLY WRONG. The problem is that when a ref is
151 deleted that is the target of an edge, there is not enough
152 information to efficiently find the source of the edge and
153 delete the edge. This leaves a dangling reference that may
154 cause problems.
155
156 b) If def-use chains AND use-def chains are built, this may
157 produce unexpected results. The problem is that the incremental
158 scanning of an insn does not know how to repair the chains that
159 point into an insn when the insn changes. So the incremental
160 scanning just deletes the chains that enter and exit the insn
161 being changed. The dangling reference issue in (a) is not a
162 problem here, but if the pass is depending on the chains being
163 maintained after insns have been modified, this technique will
164 not do the correct thing.
165
166 c) If the pass modifies insns several times, this incremental
167 updating may be expensive.
168
169 d) If the pass modifies all of the insns, as does register
170 allocation, it is simply better to rescan the entire function.
171
1722) Deferred rescanning - Calls to df_insn_rescan, df_notes_rescan, and
173 df_insn_delete do not immediately change the insn but instead make
174 a note that the insn needs to be rescanned. The next call to
175 df_analyze, df_finish_pass, or df_process_deferred_rescans will
176 cause all of the pending rescans to be processed.
177
178 This is the technique of choice if either 1a, 1b, or 1c are issues
179 in the pass. In the case of 1a or 1b, a call to df_finish_pass
180 (either manually or via TODO_df_finish) should be made before the
181 next call to df_analyze or df_process_deferred_rescans.
182
183 This mode is also used by a few passes that still rely on note_uses,
184 note_stores and rtx iterators instead of using the DF data. This
185 can be said to fall under case 1c.
186
187 To enable this mode, call df_set_flags (DF_DEFER_INSN_RESCAN).
188 (This mode can be cleared by calling df_clear_flags
189 (DF_DEFER_INSN_RESCAN) but this does not cause the deferred insns to
190 be rescanned.
191
1923) Total rescanning - In this mode the rescanning is disabled.
193 Only when insns are deleted is the df information associated with
194 it also deleted. At the end of the pass, a call must be made to
195 df_insn_rescan_all. This method is used by the register allocator
196 since it generally changes each insn multiple times (once for each ref)
197 and does not need to make use of the updated scanning information.
198
1994) Do it yourself - In this mechanism, the pass updates the insns
200 itself using the low level df primitives. Currently no pass does
201 this, but it has the advantage that it is quite efficient given
202 that the pass generally has exact knowledge of what it is changing.
203
204DATA STRUCTURES
205
206Scanning produces a `struct df_ref' data structure (ref) is allocated
207for every register reference (def or use) and this records the insn
208and bb the ref is found within. The refs are linked together in
209chains of uses and defs for each insn and for each register. Each ref
210also has a chain field that links all the use refs for a def or all
211the def refs for a use. This is used to create use-def or def-use
212chains.
213
214Different optimizations have different needs. Ultimately, only
215register allocation and schedulers should be using the bitmaps
216produced for the live register and uninitialized register problems.
217The rest of the backend should be upgraded to using and maintaining
218the linked information such as def use or use def chains.
219
220
221PHILOSOPHY:
222
223While incremental bitmaps are not worthwhile to maintain, incremental
224chains may be perfectly reasonable. The fastest way to build chains
225from scratch or after significant modifications is to build reaching
226definitions (RD) and build the chains from this.
227
228However, general algorithms for maintaining use-def or def-use chains
229are not practical. The amount of work to recompute the chain any
230chain after an arbitrary change is large. However, with a modest
231amount of work it is generally possible to have the application that
232uses the chains keep them up to date. The high level knowledge of
233what is really happening is essential to crafting efficient
234incremental algorithms.
235
236As for the bit vector problems, there is no interface to give a set of
237blocks over with to resolve the iteration. In general, restarting a
238dataflow iteration is difficult and expensive. Again, the best way to
239keep the dataflow information up to data (if this is really what is
240needed) it to formulate a problem specific solution.
241
242There are fine grained calls for creating and deleting references from
243instructions in df-scan.c. However, these are not currently connected
244to the engine that resolves the dataflow equations.
245
246
247DATA STRUCTURES:
248
249The basic object is a DF_REF (reference) and this may either be a
250DEF (definition) or a USE of a register.
251
252These are linked into a variety of lists; namely reg-def, reg-use,
253insn-def, insn-use, def-use, and use-def lists. For example, the
254reg-def lists contain all the locations that define a given register
255while the insn-use lists contain all the locations that use a
256register.
257
258Note that the reg-def and reg-use chains are generally short for
259pseudos and long for the hard registers.
260
261ACCESSING INSNS:
262
2631) The df insn information is kept in an array of DF_INSN_INFO objects.
264 The array is indexed by insn uid, and every DF_REF points to the
265 DF_INSN_INFO object of the insn that contains the reference.
266
2672) Each insn has three sets of refs, which are linked into one of three
268 lists: The insn's defs list (accessed by the DF_INSN_INFO_DEFS,
269 DF_INSN_DEFS, or DF_INSN_UID_DEFS macros), the insn's uses list
270 (accessed by the DF_INSN_INFO_USES, DF_INSN_USES, or
271 DF_INSN_UID_USES macros) or the insn's eq_uses list (accessed by the
272 DF_INSN_INFO_EQ_USES, DF_INSN_EQ_USES or DF_INSN_UID_EQ_USES macros).
273 The latter list are the list of references in REG_EQUAL or REG_EQUIV
274 notes. These macros produce a ref (or NULL), the rest of the list
275 can be obtained by traversal of the NEXT_REF field (accessed by the
276 DF_REF_NEXT_REF macro.) There is no significance to the ordering of
277 the uses or refs in an instruction.
278
2793) Each insn has a logical uid field (LUID) which is stored in the
280 DF_INSN_INFO object for the insn. The LUID field is accessed by
281 the DF_INSN_INFO_LUID, DF_INSN_LUID, and DF_INSN_UID_LUID macros.
282 When properly set, the LUID is an integer that numbers each insn in
283 the basic block, in order from the start of the block.
284 The numbers are only correct after a call to df_analyze. They will
285 rot after insns are added deleted or moved round.
286
287ACCESSING REFS:
288
289There are 4 ways to obtain access to refs:
290
2911) References are divided into two categories, REAL and ARTIFICIAL.
292
293 REAL refs are associated with instructions.
294
295 ARTIFICIAL refs are associated with basic blocks. The heads of
296 these lists can be accessed by calling df_get_artificial_defs or
297 df_get_artificial_uses for the particular basic block.
298
299 Artificial defs and uses occur both at the beginning and ends of blocks.
300
301 For blocks that area at the destination of eh edges, the
302 artificial uses and defs occur at the beginning. The defs relate
303 to the registers specified in EH_RETURN_DATA_REGNO and the uses
304 relate to the registers specified in ED_USES. Logically these
305 defs and uses should really occur along the eh edge, but there is
306 no convenient way to do this. Artificial edges that occur at the
307 beginning of the block have the DF_REF_AT_TOP flag set.
308
309 Artificial uses occur at the end of all blocks. These arise from
310 the hard registers that are always live, such as the stack
311 register and are put there to keep the code from forgetting about
312 them.
313
314 Artificial defs occur at the end of the entry block. These arise
315 from registers that are live at entry to the function.
316
3172) There are three types of refs: defs, uses and eq_uses. (Eq_uses are
318 uses that appear inside a REG_EQUAL or REG_EQUIV note.)
319
320 All of the eq_uses, uses and defs associated with each pseudo or
321 hard register may be linked in a bidirectional chain. These are
322 called reg-use or reg_def chains. If the changeable flag
323 DF_EQ_NOTES is set when the chains are built, the eq_uses will be
324 treated like uses. If it is not set they are ignored.
325
326 The first use, eq_use or def for a register can be obtained using
327 the DF_REG_USE_CHAIN, DF_REG_EQ_USE_CHAIN or DF_REG_DEF_CHAIN
328 macros. Subsequent uses for the same regno can be obtained by
329 following the next_reg field of the ref. The number of elements in
330 each of the chains can be found by using the DF_REG_USE_COUNT,
331 DF_REG_EQ_USE_COUNT or DF_REG_DEF_COUNT macros.
332
333 In previous versions of this code, these chains were ordered. It
334 has not been practical to continue this practice.
335
3363) If def-use or use-def chains are built, these can be traversed to
337 get to other refs. If the flag DF_EQ_NOTES has been set, the chains
338 include the eq_uses. Otherwise these are ignored when building the
339 chains.
340
3414) An array of all of the uses (and an array of all of the defs) can
342 be built. These arrays are indexed by the value in the id
343 structure. These arrays are only lazily kept up to date, and that
344 process can be expensive. To have these arrays built, call
345 df_reorganize_defs or df_reorganize_uses. If the flag DF_EQ_NOTES
346 has been set the array will contain the eq_uses. Otherwise these
347 are ignored when building the array and assigning the ids. Note
348 that the values in the id field of a ref may change across calls to
349 df_analyze or df_reorganize_defs or df_reorganize_uses.
350
351 If the only use of this array is to find all of the refs, it is
352 better to traverse all of the registers and then traverse all of
353 reg-use or reg-def chains.
354
355NOTES:
356
357Embedded addressing side-effects, such as POST_INC or PRE_INC, generate
358both a use and a def. These are both marked read/write to show that they
359are dependent. For example, (set (reg 40) (mem (post_inc (reg 42))))
360will generate a use of reg 42 followed by a def of reg 42 (both marked
361read/write). Similarly, (set (reg 40) (mem (pre_dec (reg 41))))
362generates a use of reg 41 then a def of reg 41 (both marked read/write),
363even though reg 41 is decremented before it is used for the memory
364address in this second example.
365
366A set to a REG inside a ZERO_EXTRACT, or a set to a non-paradoxical SUBREG
367for which the number of word_mode units covered by the outer mode is
368smaller than that covered by the inner mode, invokes a read-modify-write
369operation. We generate both a use and a def and again mark them
370read/write.
371
372Paradoxical subreg writes do not leave a trace of the old content, so they
373are write-only operations.
374*/
375
376
377#include "config.h"
378#include "system.h"
379#include "coretypes.h"
380#include "backend.h"
381#include "rtl.h"
382#include "df.h"
383#include "memmodel.h"
384#include "emit-rtl.h"
385#include "cfganal.h"
386#include "tree-pass.h"
387#include "cfgloop.h"
388
389static void *df_get_bb_info (struct dataflow *, unsigned int);
390static void df_set_bb_info (struct dataflow *, unsigned int, void *);
391static void df_clear_bb_info (struct dataflow *, unsigned int);
392#ifdef DF_DEBUG_CFG
393static void df_set_clean_cfg (void);
394#endif
395
396/* The obstack on which regsets are allocated. */
397struct bitmap_obstack reg_obstack;
398
399/* An obstack for bitmap not related to specific dataflow problems.
400 This obstack should e.g. be used for bitmaps with a short life time
401 such as temporary bitmaps. */
402
403bitmap_obstack df_bitmap_obstack;
404
405
406/*----------------------------------------------------------------------------
407 Functions to create, destroy and manipulate an instance of df.
408----------------------------------------------------------------------------*/
409
410struct df_d *df;
411
412/* Add PROBLEM (and any dependent problems) to the DF instance. */
413
414void
415df_add_problem (const struct df_problem *problem)
416{
417 struct dataflow *dflow;
418 int i;
419
420 /* First try to add the dependent problem. */
421 if (problem->dependent_problem)
422 df_add_problem (problem->dependent_problem);
423
424 /* Check to see if this problem has already been defined. If it
425 has, just return that instance, if not, add it to the end of the
426 vector. */
427 dflow = df->problems_by_index[problem->id];
428 if (dflow)
429 return;
430
431 /* Make a new one and add it to the end. */
432 dflow = XCNEW (struct dataflow);
433 dflow->problem = problem;
434 dflow->computed = false;
435 dflow->solutions_dirty = true;
436 df->problems_by_index[dflow->problem->id] = dflow;
437
438 /* Keep the defined problems ordered by index. This solves the
439 problem that RI will use the information from UREC if UREC has
440 been defined, or from LIVE if LIVE is defined and otherwise LR.
441 However for this to work, the computation of RI must be pushed
442 after which ever of those problems is defined, but we do not
443 require any of those except for LR to have actually been
444 defined. */
445 df->num_problems_defined++;
446 for (i = df->num_problems_defined - 2; i >= 0; i--)
447 {
448 if (problem->id < df->problems_in_order[i]->problem->id)
449 df->problems_in_order[i+1] = df->problems_in_order[i];
450 else
451 {
452 df->problems_in_order[i+1] = dflow;
453 return;
454 }
455 }
456 df->problems_in_order[0] = dflow;
457}
458
459
460/* Set the MASK flags in the DFLOW problem. The old flags are
461 returned. If a flag is not allowed to be changed this will fail if
462 checking is enabled. */
463int
464df_set_flags (int changeable_flags)
465{
466 int old_flags = df->changeable_flags;
467 df->changeable_flags |= changeable_flags;
468 return old_flags;
469}
470
471
472/* Clear the MASK flags in the DFLOW problem. The old flags are
473 returned. If a flag is not allowed to be changed this will fail if
474 checking is enabled. */
475int
476df_clear_flags (int changeable_flags)
477{
478 int old_flags = df->changeable_flags;
479 df->changeable_flags &= ~changeable_flags;
480 return old_flags;
481}
482
483
484/* Set the blocks that are to be considered for analysis. If this is
485 not called or is called with null, the entire function in
486 analyzed. */
487
488void
489df_set_blocks (bitmap blocks)
490{
491 if (blocks)
492 {
493 if (dump_file)
494 bitmap_print (dump_file, blocks, "setting blocks to analyze ", "\n");
495 if (df->blocks_to_analyze)
496 {
497 /* This block is called to change the focus from one subset
498 to another. */
499 int p;
500 auto_bitmap diff (&df_bitmap_obstack);
501 bitmap_and_compl (diff, df->blocks_to_analyze, blocks);
502 for (p = 0; p < df->num_problems_defined; p++)
503 {
504 struct dataflow *dflow = df->problems_in_order[p];
505 if (dflow->optional_p && dflow->problem->reset_fun)
506 dflow->problem->reset_fun (df->blocks_to_analyze);
507 else if (dflow->problem->free_blocks_on_set_blocks)
508 {
509 bitmap_iterator bi;
510 unsigned int bb_index;
511
512 EXECUTE_IF_SET_IN_BITMAP (diff, 0, bb_index, bi)
513 {
514 basic_block bb = BASIC_BLOCK_FOR_FN (cfun, bb_index);
515 if (bb)
516 {
517 void *bb_info = df_get_bb_info (dflow, bb_index);
518 dflow->problem->free_bb_fun (bb, bb_info);
519 df_clear_bb_info (dflow, bb_index);
520 }
521 }
522 }
523 }
524 }
525 else
526 {
527 /* This block of code is executed to change the focus from
528 the entire function to a subset. */
529 bitmap_head blocks_to_reset;
530 bool initialized = false;
531 int p;
532 for (p = 0; p < df->num_problems_defined; p++)
533 {
534 struct dataflow *dflow = df->problems_in_order[p];
535 if (dflow->optional_p && dflow->problem->reset_fun)
536 {
537 if (!initialized)
538 {
539 basic_block bb;
540 bitmap_initialize (&blocks_to_reset, &df_bitmap_obstack);
541 FOR_ALL_BB_FN (bb, cfun)
542 {
543 bitmap_set_bit (&blocks_to_reset, bb->index);
544 }
545 }
546 dflow->problem->reset_fun (&blocks_to_reset);
547 }
548 }
549 if (initialized)
550 bitmap_clear (&blocks_to_reset);
551
552 df->blocks_to_analyze = BITMAP_ALLOC (&df_bitmap_obstack);
553 }
554 bitmap_copy (df->blocks_to_analyze, blocks);
555 df->analyze_subset = true;
556 }
557 else
558 {
559 /* This block is executed to reset the focus to the entire
560 function. */
561 if (dump_file)
562 fprintf (dump_file, "clearing blocks_to_analyze\n");
563 if (df->blocks_to_analyze)
564 {
565 BITMAP_FREE (df->blocks_to_analyze);
566 df->blocks_to_analyze = NULL;
567 }
568 df->analyze_subset = false;
569 }
570
571 /* Setting the blocks causes the refs to be unorganized since only
572 the refs in the blocks are seen. */
573 df_maybe_reorganize_def_refs (DF_REF_ORDER_NO_TABLE);
574 df_maybe_reorganize_use_refs (DF_REF_ORDER_NO_TABLE);
575 df_mark_solutions_dirty ();
576}
577
578
579/* Delete a DFLOW problem (and any problems that depend on this
580 problem). */
581
582void
583df_remove_problem (struct dataflow *dflow)
584{
585 const struct df_problem *problem;
586 int i;
587
588 if (!dflow)
589 return;
590
591 problem = dflow->problem;
592 gcc_assert (problem->remove_problem_fun);
593
594 /* Delete any problems that depended on this problem first. */
595 for (i = 0; i < df->num_problems_defined; i++)
596 if (df->problems_in_order[i]->problem->dependent_problem == problem)
597 df_remove_problem (df->problems_in_order[i]);
598
599 /* Now remove this problem. */
600 for (i = 0; i < df->num_problems_defined; i++)
601 if (df->problems_in_order[i] == dflow)
602 {
603 int j;
604 for (j = i + 1; j < df->num_problems_defined; j++)
605 df->problems_in_order[j-1] = df->problems_in_order[j];
606 df->problems_in_order[j-1] = NULL;
607 df->num_problems_defined--;
608 break;
609 }
610
611 (problem->remove_problem_fun) ();
612 df->problems_by_index[problem->id] = NULL;
613}
614
615
616/* Remove all of the problems that are not permanent. Scanning, LR
617 and (at -O2 or higher) LIVE are permanent, the rest are removable.
618 Also clear all of the changeable_flags. */
619
620void
621df_finish_pass (bool verify ATTRIBUTE_UNUSED)
622{
623 int i;
624
625#ifdef ENABLE_DF_CHECKING
626 int saved_flags;
627#endif
628
629 if (!df)
630 return;
631
632 df_maybe_reorganize_def_refs (DF_REF_ORDER_NO_TABLE);
633 df_maybe_reorganize_use_refs (DF_REF_ORDER_NO_TABLE);
634
635#ifdef ENABLE_DF_CHECKING
636 saved_flags = df->changeable_flags;
637#endif
638
639 /* We iterate over problems by index as each problem removed will
640 lead to problems_in_order to be reordered. */
641 for (i = 0; i < DF_LAST_PROBLEM_PLUS1; i++)
642 {
643 struct dataflow *dflow = df->problems_by_index[i];
644
645 if (dflow && dflow->optional_p)
646 df_remove_problem (dflow);
647 }
648
649 /* Clear all of the flags. */
650 df->changeable_flags = 0;
651 df_process_deferred_rescans ();
652
653 /* Set the focus back to the whole function. */
654 if (df->blocks_to_analyze)
655 {
656 BITMAP_FREE (df->blocks_to_analyze);
657 df->blocks_to_analyze = NULL;
658 df_mark_solutions_dirty ();
659 df->analyze_subset = false;
660 }
661
662#ifdef ENABLE_DF_CHECKING
663 /* Verification will fail in DF_NO_INSN_RESCAN. */
664 if (!(saved_flags & DF_NO_INSN_RESCAN))
665 {
666 df_lr_verify_transfer_functions ();
667 if (df_live)
668 df_live_verify_transfer_functions ();
669 }
670
671#ifdef DF_DEBUG_CFG
672 df_set_clean_cfg ();
673#endif
674#endif
675
676 if (flag_checking && verify)
677 df->changeable_flags |= DF_VERIFY_SCHEDULED;
678}
679
680
681/* Set up the dataflow instance for the entire back end. */
682
683static unsigned int
684rest_of_handle_df_initialize (void)
685{
686 gcc_assert (!df);
687 df = XCNEW (struct df_d);
688 df->changeable_flags = 0;
689
690 bitmap_obstack_initialize (&df_bitmap_obstack);
691
692 /* Set this to a conservative value. Stack_ptr_mod will compute it
693 correctly later. */
694 crtl->sp_is_unchanging = 0;
695
696 df_scan_add_problem ();
697 df_scan_alloc (NULL);
698
699 /* These three problems are permanent. */
700 df_lr_add_problem ();
701 if (optimize > 1)
702 df_live_add_problem ();
703
704 df->postorder = XNEWVEC (int, last_basic_block_for_fn (cfun));
705 df->n_blocks = post_order_compute (df->postorder, true, true);
706 inverted_post_order_compute (&df->postorder_inverted);
707 gcc_assert ((unsigned) df->n_blocks == df->postorder_inverted.length ());
708
709 df->hard_regs_live_count = XCNEWVEC (unsigned int, FIRST_PSEUDO_REGISTER);
710
711 df_hard_reg_init ();
712 /* After reload, some ports add certain bits to regs_ever_live so
713 this cannot be reset. */
714 df_compute_regs_ever_live (true);
715 df_scan_blocks ();
716 df_compute_regs_ever_live (false);
717 return 0;
718}
719
720
721namespace {
722
723const pass_data pass_data_df_initialize_opt =
724{
725 RTL_PASS, /* type */
726 "dfinit", /* name */
727 OPTGROUP_NONE, /* optinfo_flags */
728 TV_DF_SCAN, /* tv_id */
729 0, /* properties_required */
730 0, /* properties_provided */
731 0, /* properties_destroyed */
732 0, /* todo_flags_start */
733 0, /* todo_flags_finish */
734};
735
736class pass_df_initialize_opt : public rtl_opt_pass
737{
738public:
739 pass_df_initialize_opt (gcc::context *ctxt)
740 : rtl_opt_pass (pass_data_df_initialize_opt, ctxt)
741 {}
742
743 /* opt_pass methods: */
744 virtual bool gate (function *) { return optimize > 0; }
745 virtual unsigned int execute (function *)
746 {
747 return rest_of_handle_df_initialize ();
748 }
749
750}; // class pass_df_initialize_opt
751
752} // anon namespace
753
754rtl_opt_pass *
755make_pass_df_initialize_opt (gcc::context *ctxt)
756{
757 return new pass_df_initialize_opt (ctxt);
758}
759
760
761namespace {
762
763const pass_data pass_data_df_initialize_no_opt =
764{
765 RTL_PASS, /* type */
766 "no-opt dfinit", /* name */
767 OPTGROUP_NONE, /* optinfo_flags */
768 TV_DF_SCAN, /* tv_id */
769 0, /* properties_required */
770 0, /* properties_provided */
771 0, /* properties_destroyed */
772 0, /* todo_flags_start */
773 0, /* todo_flags_finish */
774};
775
776class pass_df_initialize_no_opt : public rtl_opt_pass
777{
778public:
779 pass_df_initialize_no_opt (gcc::context *ctxt)
780 : rtl_opt_pass (pass_data_df_initialize_no_opt, ctxt)
781 {}
782
783 /* opt_pass methods: */
784 virtual bool gate (function *) { return optimize == 0; }
785 virtual unsigned int execute (function *)
786 {
787 return rest_of_handle_df_initialize ();
788 }
789
790}; // class pass_df_initialize_no_opt
791
792} // anon namespace
793
794rtl_opt_pass *
795make_pass_df_initialize_no_opt (gcc::context *ctxt)
796{
797 return new pass_df_initialize_no_opt (ctxt);
798}
799
800
801/* Free all the dataflow info and the DF structure. This should be
802 called from the df_finish macro which also NULLs the parm. */
803
804static unsigned int
805rest_of_handle_df_finish (void)
806{
807 int i;
808
809 gcc_assert (df);
810
811 for (i = 0; i < df->num_problems_defined; i++)
812 {
813 struct dataflow *dflow = df->problems_in_order[i];
814 dflow->problem->free_fun ();
815 }
816
817 free (df->postorder);
818 df->postorder_inverted.release ();
819 free (df->hard_regs_live_count);
820 free (df);
821 df = NULL;
822
823 bitmap_obstack_release (&df_bitmap_obstack);
824 return 0;
825}
826
827
828namespace {
829
830const pass_data pass_data_df_finish =
831{
832 RTL_PASS, /* type */
833 "dfinish", /* name */
834 OPTGROUP_NONE, /* optinfo_flags */
835 TV_NONE, /* 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};
842
843class pass_df_finish : public rtl_opt_pass
844{
845public:
846 pass_df_finish (gcc::context *ctxt)
847 : rtl_opt_pass (pass_data_df_finish, ctxt)
848 {}
849
850 /* opt_pass methods: */
851 virtual unsigned int execute (function *)
852 {
853 return rest_of_handle_df_finish ();
854 }
855
856}; // class pass_df_finish
857
858} // anon namespace
859
860rtl_opt_pass *
861make_pass_df_finish (gcc::context *ctxt)
862{
863 return new pass_df_finish (ctxt);
864}
865
866
867
868
869
870/*----------------------------------------------------------------------------
871 The general data flow analysis engine.
872----------------------------------------------------------------------------*/
873
874/* Return time BB when it was visited for last time. */
875#define BB_LAST_CHANGE_AGE(bb) ((ptrdiff_t)(bb)->aux)
876
877/* Helper function for df_worklist_dataflow.
878 Propagate the dataflow forward.
879 Given a BB_INDEX, do the dataflow propagation
880 and set bits on for successors in PENDING
881 if the out set of the dataflow has changed.
882
883 AGE specify time when BB was visited last time.
884 AGE of 0 means we are visiting for first time and need to
885 compute transfer function to initialize datastructures.
886 Otherwise we re-do transfer function only if something change
887 while computing confluence functions.
888 We need to compute confluence only of basic block that are younger
889 then last visit of the BB.
890
891 Return true if BB info has changed. This is always the case
892 in the first visit. */
893
894static bool
895df_worklist_propagate_forward (struct dataflow *dataflow,
896 unsigned bb_index,
897 unsigned *bbindex_to_postorder,
898 bitmap pending,
899 sbitmap considered,
900 ptrdiff_t age)
901{
902 edge e;
903 edge_iterator ei;
904 basic_block bb = BASIC_BLOCK_FOR_FN (cfun, bb_index);
905 bool changed = !age;
906
907 /* Calculate <conf_op> of incoming edges. */
908 if (EDGE_COUNT (bb->preds) > 0)
909 FOR_EACH_EDGE (e, ei, bb->preds)
910 {
911 if (age <= BB_LAST_CHANGE_AGE (e->src)
912 && bitmap_bit_p (considered, e->src->index))
913 changed |= dataflow->problem->con_fun_n (e);
914 }
915 else if (dataflow->problem->con_fun_0)
916 dataflow->problem->con_fun_0 (bb);
917
918 if (changed
919 && dataflow->problem->trans_fun (bb_index))
920 {
921 /* The out set of this block has changed.
922 Propagate to the outgoing blocks. */
923 FOR_EACH_EDGE (e, ei, bb->succs)
924 {
925 unsigned ob_index = e->dest->index;
926
927 if (bitmap_bit_p (considered, ob_index))
928 bitmap_set_bit (pending, bbindex_to_postorder[ob_index]);
929 }
930 return true;
931 }
932 return false;
933}
934
935
936/* Helper function for df_worklist_dataflow.
937 Propagate the dataflow backward. */
938
939static bool
940df_worklist_propagate_backward (struct dataflow *dataflow,
941 unsigned bb_index,
942 unsigned *bbindex_to_postorder,
943 bitmap pending,
944 sbitmap considered,
945 ptrdiff_t age)
946{
947 edge e;
948 edge_iterator ei;
949 basic_block bb = BASIC_BLOCK_FOR_FN (cfun, bb_index);
950 bool changed = !age;
951
952 /* Calculate <conf_op> of incoming edges. */
953 if (EDGE_COUNT (bb->succs) > 0)
954 FOR_EACH_EDGE (e, ei, bb->succs)
955 {
956 if (age <= BB_LAST_CHANGE_AGE (e->dest)
957 && bitmap_bit_p (considered, e->dest->index))
958 changed |= dataflow->problem->con_fun_n (e);
959 }
960 else if (dataflow->problem->con_fun_0)
961 dataflow->problem->con_fun_0 (bb);
962
963 if (changed
964 && dataflow->problem->trans_fun (bb_index))
965 {
966 /* The out set of this block has changed.
967 Propagate to the outgoing blocks. */
968 FOR_EACH_EDGE (e, ei, bb->preds)
969 {
970 unsigned ob_index = e->src->index;
971
972 if (bitmap_bit_p (considered, ob_index))
973 bitmap_set_bit (pending, bbindex_to_postorder[ob_index]);
974 }
975 return true;
976 }
977 return false;
978}
979
980/* Main dataflow solver loop.
981
982 DATAFLOW is problem we are solving, PENDING is worklist of basic blocks we
983 need to visit.
984 BLOCK_IN_POSTORDER is array of size N_BLOCKS specifying postorder in BBs and
985 BBINDEX_TO_POSTORDER is array mapping back BB->index to postorder position.
986 PENDING will be freed.
987
988 The worklists are bitmaps indexed by postorder positions.
989
990 The function implements standard algorithm for dataflow solving with two
991 worklists (we are processing WORKLIST and storing new BBs to visit in
992 PENDING).
993
994 As an optimization we maintain ages when BB was changed (stored in bb->aux)
995 and when it was last visited (stored in last_visit_age). This avoids need
996 to re-do confluence function for edges to basic blocks whose source
997 did not change since destination was visited last time. */
998
999static void
1000df_worklist_dataflow_doublequeue (struct dataflow *dataflow,
1001 bitmap pending,
1002 sbitmap considered,
1003 int *blocks_in_postorder,
1004 unsigned *bbindex_to_postorder,
1005 int n_blocks)
1006{
1007 enum df_flow_dir dir = dataflow->problem->dir;
1008 int dcount = 0;
1009 bitmap worklist = BITMAP_ALLOC (&df_bitmap_obstack);
1010 int age = 0;
1011 bool changed;
1012 vec<int> last_visit_age = vNULL;
1013 int prev_age;
1014 basic_block bb;
1015 int i;
1016
1017 last_visit_age.safe_grow_cleared (n_blocks);
1018
1019 /* Double-queueing. Worklist is for the current iteration,
1020 and pending is for the next. */
1021 while (!bitmap_empty_p (pending))
1022 {
1023 bitmap_iterator bi;
1024 unsigned int index;
1025
1026 std::swap (pending, worklist);
1027
1028 EXECUTE_IF_SET_IN_BITMAP (worklist, 0, index, bi)
1029 {
1030 unsigned bb_index;
1031 dcount++;
1032
1033 bitmap_clear_bit (pending, index);
1034 bb_index = blocks_in_postorder[index];
1035 bb = BASIC_BLOCK_FOR_FN (cfun, bb_index);
1036 prev_age = last_visit_age[index];
1037 if (dir == DF_FORWARD)
1038 changed = df_worklist_propagate_forward (dataflow, bb_index,
1039 bbindex_to_postorder,
1040 pending, considered,
1041 prev_age);
1042 else
1043 changed = df_worklist_propagate_backward (dataflow, bb_index,
1044 bbindex_to_postorder,
1045 pending, considered,
1046 prev_age);
1047 last_visit_age[index] = ++age;
1048 if (changed)
1049 bb->aux = (void *)(ptrdiff_t)age;
1050 }
1051 bitmap_clear (worklist);
1052 }
1053 for (i = 0; i < n_blocks; i++)
1054 BASIC_BLOCK_FOR_FN (cfun, blocks_in_postorder[i])->aux = NULL;
1055
1056 BITMAP_FREE (worklist);
1057 BITMAP_FREE (pending);
1058 last_visit_age.release ();
1059
1060 /* Dump statistics. */
1061 if (dump_file)
1062 fprintf (dump_file, "df_worklist_dataflow_doublequeue:"
1063 " n_basic_blocks %d n_edges %d"
1064 " count %d (%5.2g)\n",
1065 n_basic_blocks_for_fn (cfun), n_edges_for_fn (cfun),
1066 dcount, dcount / (float)n_basic_blocks_for_fn (cfun));
1067}
1068
1069/* Worklist-based dataflow solver. It uses sbitmap as a worklist,
1070 with "n"-th bit representing the n-th block in the reverse-postorder order.
1071 The solver is a double-queue algorithm similar to the "double stack" solver
1072 from Cooper, Harvey and Kennedy, "Iterative data-flow analysis, Revisited".
1073 The only significant difference is that the worklist in this implementation
1074 is always sorted in RPO of the CFG visiting direction. */
1075
1076void
1077df_worklist_dataflow (struct dataflow *dataflow,
1078 bitmap blocks_to_consider,
1079 int *blocks_in_postorder,
1080 int n_blocks)
1081{
1082 bitmap pending = BITMAP_ALLOC (&df_bitmap_obstack);
1083 bitmap_iterator bi;
1084 unsigned int *bbindex_to_postorder;
1085 int i;
1086 unsigned int index;
1087 enum df_flow_dir dir = dataflow->problem->dir;
1088
1089 gcc_assert (dir != DF_NONE);
1090
1091 /* BBINDEX_TO_POSTORDER maps the bb->index to the reverse postorder. */
1092 bbindex_to_postorder = XNEWVEC (unsigned int,
1093 last_basic_block_for_fn (cfun));
1094
1095 /* Initialize the array to an out-of-bound value. */
1096 for (i = 0; i < last_basic_block_for_fn (cfun); i++)
1097 bbindex_to_postorder[i] = last_basic_block_for_fn (cfun);
1098
1099 /* Initialize the considered map. */
1100 auto_sbitmap considered (last_basic_block_for_fn (cfun));
1101 bitmap_clear (considered);
1102 EXECUTE_IF_SET_IN_BITMAP (blocks_to_consider, 0, index, bi)
1103 {
1104 bitmap_set_bit (considered, index);
1105 }
1106
1107 /* Initialize the mapping of block index to postorder. */
1108 for (i = 0; i < n_blocks; i++)
1109 {
1110 bbindex_to_postorder[blocks_in_postorder[i]] = i;
1111 /* Add all blocks to the worklist. */
1112 bitmap_set_bit (pending, i);
1113 }
1114
1115 /* Initialize the problem. */
1116 if (dataflow->problem->init_fun)
1117 dataflow->problem->init_fun (blocks_to_consider);
1118
1119 /* Solve it. */
1120 df_worklist_dataflow_doublequeue (dataflow, pending, considered,
1121 blocks_in_postorder,
1122 bbindex_to_postorder,
1123 n_blocks);
1124 free (bbindex_to_postorder);
1125}
1126
1127
1128/* Remove the entries not in BLOCKS from the LIST of length LEN, preserving
1129 the order of the remaining entries. Returns the length of the resulting
1130 list. */
1131
1132static unsigned
1133df_prune_to_subcfg (int list[], unsigned len, bitmap blocks)
1134{
1135 unsigned act, last;
1136
1137 for (act = 0, last = 0; act < len; act++)
1138 if (bitmap_bit_p (blocks, list[act]))
1139 list[last++] = list[act];
1140
1141 return last;
1142}
1143
1144
1145/* Execute dataflow analysis on a single dataflow problem.
1146
1147 BLOCKS_TO_CONSIDER are the blocks whose solution can either be
1148 examined or will be computed. For calls from DF_ANALYZE, this is
1149 the set of blocks that has been passed to DF_SET_BLOCKS.
1150*/
1151
1152void
1153df_analyze_problem (struct dataflow *dflow,
1154 bitmap blocks_to_consider,
1155 int *postorder, int n_blocks)
1156{
1157 timevar_push (dflow->problem->tv_id);
1158
1159 /* (Re)Allocate the datastructures necessary to solve the problem. */
1160 if (dflow->problem->alloc_fun)
1161 dflow->problem->alloc_fun (blocks_to_consider);
1162
1163#ifdef ENABLE_DF_CHECKING
1164 if (dflow->problem->verify_start_fun)
1165 dflow->problem->verify_start_fun ();
1166#endif
1167
1168 /* Set up the problem and compute the local information. */
1169 if (dflow->problem->local_compute_fun)
1170 dflow->problem->local_compute_fun (blocks_to_consider);
1171
1172 /* Solve the equations. */
1173 if (dflow->problem->dataflow_fun)
1174 dflow->problem->dataflow_fun (dflow, blocks_to_consider,
1175 postorder, n_blocks);
1176
1177 /* Massage the solution. */
1178 if (dflow->problem->finalize_fun)
1179 dflow->problem->finalize_fun (blocks_to_consider);
1180
1181#ifdef ENABLE_DF_CHECKING
1182 if (dflow->problem->verify_end_fun)
1183 dflow->problem->verify_end_fun ();
1184#endif
1185
1186 timevar_pop (dflow->problem->tv_id);
1187
1188 dflow->computed = true;
1189}
1190
1191
1192/* Analyze dataflow info. */
1193
1194static void
1195df_analyze_1 (void)
1196{
1197 int i;
1198
1199 /* These should be the same. */
1200 gcc_assert ((unsigned) df->n_blocks == df->postorder_inverted.length ());
1201
1202 /* We need to do this before the df_verify_all because this is
1203 not kept incrementally up to date. */
1204 df_compute_regs_ever_live (false);
1205 df_process_deferred_rescans ();
1206
1207 if (dump_file)
1208 fprintf (dump_file, "df_analyze called\n");
1209
1210#ifndef ENABLE_DF_CHECKING
1211 if (df->changeable_flags & DF_VERIFY_SCHEDULED)
1212#endif
1213 df_verify ();
1214
1215 /* Skip over the DF_SCAN problem. */
1216 for (i = 1; i < df->num_problems_defined; i++)
1217 {
1218 struct dataflow *dflow = df->problems_in_order[i];
1219 if (dflow->solutions_dirty)
1220 {
1221 if (dflow->problem->dir == DF_FORWARD)
1222 df_analyze_problem (dflow,
1223 df->blocks_to_analyze,
1224 df->postorder_inverted.address (),
1225 df->postorder_inverted.length ());
1226 else
1227 df_analyze_problem (dflow,
1228 df->blocks_to_analyze,
1229 df->postorder,
1230 df->n_blocks);
1231 }
1232 }
1233
1234 if (!df->analyze_subset)
1235 {
1236 BITMAP_FREE (df->blocks_to_analyze);
1237 df->blocks_to_analyze = NULL;
1238 }
1239
1240#ifdef DF_DEBUG_CFG
1241 df_set_clean_cfg ();
1242#endif
1243}
1244
1245/* Analyze dataflow info. */
1246
1247void
1248df_analyze (void)
1249{
1250 bitmap current_all_blocks = BITMAP_ALLOC (&df_bitmap_obstack);
1251
1252 free (df->postorder);
1253 df->postorder = XNEWVEC (int, last_basic_block_for_fn (cfun));
1254 df->n_blocks = post_order_compute (df->postorder, true, true);
1255 df->postorder_inverted.truncate (0);
1256 inverted_post_order_compute (&df->postorder_inverted);
1257
1258 for (int i = 0; i < df->n_blocks; i++)
1259 bitmap_set_bit (current_all_blocks, df->postorder[i]);
1260
1261 if (flag_checking)
1262 {
1263 /* Verify that POSTORDER_INVERTED only contains blocks reachable from
1264 the ENTRY block. */
1265 for (unsigned int i = 0; i < df->postorder_inverted.length (); i++)
1266 gcc_assert (bitmap_bit_p (current_all_blocks,
1267 df->postorder_inverted[i]));
1268 }
1269
1270 /* Make sure that we have pruned any unreachable blocks from these
1271 sets. */
1272 if (df->analyze_subset)
1273 {
1274 bitmap_and_into (df->blocks_to_analyze, current_all_blocks);
1275 df->n_blocks = df_prune_to_subcfg (df->postorder,
1276 df->n_blocks, df->blocks_to_analyze);
1277 unsigned int newlen = df_prune_to_subcfg (df->postorder_inverted.address (),
1278 df->postorder_inverted.length (),
1279 df->blocks_to_analyze);
1280 df->postorder_inverted.truncate (newlen);
1281 BITMAP_FREE (current_all_blocks);
1282 }
1283 else
1284 {
1285 df->blocks_to_analyze = current_all_blocks;
1286 current_all_blocks = NULL;
1287 }
1288
1289 df_analyze_1 ();
1290}
1291
1292/* Compute the reverse top sort order of the sub-CFG specified by LOOP.
1293 Returns the number of blocks which is always loop->num_nodes. */
1294
1295static int
1296loop_post_order_compute (int *post_order, struct loop *loop)
1297{
1298 edge_iterator *stack;
1299 int sp;
1300 int post_order_num = 0;
1301
1302 /* Allocate stack for back-tracking up CFG. */
1303 stack = XNEWVEC (edge_iterator, loop->num_nodes + 1);
1304 sp = 0;
1305
1306 /* Allocate bitmap to track nodes that have been visited. */
1307 auto_bitmap visited;
1308
1309 /* Push the first edge on to the stack. */
1310 stack[sp++] = ei_start (loop_preheader_edge (loop)->src->succs);
1311
1312 while (sp)
1313 {
1314 edge_iterator ei;
1315 basic_block src;
1316 basic_block dest;
1317
1318 /* Look at the edge on the top of the stack. */
1319 ei = stack[sp - 1];
1320 src = ei_edge (ei)->src;
1321 dest = ei_edge (ei)->dest;
1322
1323 /* Check if the edge destination has been visited yet and mark it
1324 if not so. */
1325 if (flow_bb_inside_loop_p (loop, dest)
1326 && bitmap_set_bit (visited, dest->index))
1327 {
1328 if (EDGE_COUNT (dest->succs) > 0)
1329 /* Since the DEST node has been visited for the first
1330 time, check its successors. */
1331 stack[sp++] = ei_start (dest->succs);
1332 else
1333 post_order[post_order_num++] = dest->index;
1334 }
1335 else
1336 {
1337 if (ei_one_before_end_p (ei)
1338 && src != loop_preheader_edge (loop)->src)
1339 post_order[post_order_num++] = src->index;
1340
1341 if (!ei_one_before_end_p (ei))
1342 ei_next (&stack[sp - 1]);
1343 else
1344 sp--;
1345 }
1346 }
1347
1348 free (stack);
1349
1350 return post_order_num;
1351}
1352
1353/* Compute the reverse top sort order of the inverted sub-CFG specified
1354 by LOOP. Returns the number of blocks which is always loop->num_nodes. */
1355
1356static void
1357loop_inverted_post_order_compute (vec<int> *post_order, struct loop *loop)
1358{
1359 basic_block bb;
1360 edge_iterator *stack;
1361 int sp;
1362
1363 post_order->reserve_exact (loop->num_nodes);
1364
1365 /* Allocate stack for back-tracking up CFG. */
1366 stack = XNEWVEC (edge_iterator, loop->num_nodes + 1);
1367 sp = 0;
1368
1369 /* Allocate bitmap to track nodes that have been visited. */
1370 auto_bitmap visited;
1371
1372 /* Put all latches into the initial work list. In theory we'd want
1373 to start from loop exits but then we'd have the special case of
1374 endless loops. It doesn't really matter for DF iteration order and
1375 handling latches last is probably even better. */
1376 stack[sp++] = ei_start (loop->header->preds);
1377 bitmap_set_bit (visited, loop->header->index);
1378
1379 /* The inverted traversal loop. */
1380 while (sp)
1381 {
1382 edge_iterator ei;
1383 basic_block pred;
1384
1385 /* Look at the edge on the top of the stack. */
1386 ei = stack[sp - 1];
1387 bb = ei_edge (ei)->dest;
1388 pred = ei_edge (ei)->src;
1389
1390 /* Check if the predecessor has been visited yet and mark it
1391 if not so. */
1392 if (flow_bb_inside_loop_p (loop, pred)
1393 && bitmap_set_bit (visited, pred->index))
1394 {
1395 if (EDGE_COUNT (pred->preds) > 0)
1396 /* Since the predecessor node has been visited for the first
1397 time, check its predecessors. */
1398 stack[sp++] = ei_start (pred->preds);
1399 else
1400 post_order->quick_push (pred->index);
1401 }
1402 else
1403 {
1404 if (flow_bb_inside_loop_p (loop, bb)
1405 && ei_one_before_end_p (ei))
1406 post_order->quick_push (bb->index);
1407
1408 if (!ei_one_before_end_p (ei))
1409 ei_next (&stack[sp - 1]);
1410 else
1411 sp--;
1412 }
1413 }
1414
1415 free (stack);
1416}
1417
1418
1419/* Analyze dataflow info for the basic blocks contained in LOOP. */
1420
1421void
1422df_analyze_loop (struct loop *loop)
1423{
1424 free (df->postorder);
1425
1426 df->postorder = XNEWVEC (int, loop->num_nodes);
1427 df->postorder_inverted.truncate (0);
1428 df->n_blocks = loop_post_order_compute (df->postorder, loop);
1429 loop_inverted_post_order_compute (&df->postorder_inverted, loop);
1430 gcc_assert ((unsigned) df->n_blocks == loop->num_nodes);
1431 gcc_assert (df->postorder_inverted.length () == loop->num_nodes);
1432
1433 bitmap blocks = BITMAP_ALLOC (&df_bitmap_obstack);
1434 for (int i = 0; i < df->n_blocks; ++i)
1435 bitmap_set_bit (blocks, df->postorder[i]);
1436 df_set_blocks (blocks);
1437 BITMAP_FREE (blocks);
1438
1439 df_analyze_1 ();
1440}
1441
1442
1443/* Return the number of basic blocks from the last call to df_analyze. */
1444
1445int
1446df_get_n_blocks (enum df_flow_dir dir)
1447{
1448 gcc_assert (dir != DF_NONE);
1449
1450 if (dir == DF_FORWARD)
1451 {
1452 gcc_assert (df->postorder_inverted.length ());
1453 return df->postorder_inverted.length ();
1454 }
1455
1456 gcc_assert (df->postorder);
1457 return df->n_blocks;
1458}
1459
1460
1461/* Return a pointer to the array of basic blocks in the reverse postorder.
1462 Depending on the direction of the dataflow problem,
1463 it returns either the usual reverse postorder array
1464 or the reverse postorder of inverted traversal. */
1465int *
1466df_get_postorder (enum df_flow_dir dir)
1467{
1468 gcc_assert (dir != DF_NONE);
1469
1470 if (dir == DF_FORWARD)
1471 {
1472 gcc_assert (df->postorder_inverted.length ());
1473 return df->postorder_inverted.address ();
1474 }
1475 gcc_assert (df->postorder);
1476 return df->postorder;
1477}
1478
1479static struct df_problem user_problem;
1480static struct dataflow user_dflow;
1481
1482/* Interface for calling iterative dataflow with user defined
1483 confluence and transfer functions. All that is necessary is to
1484 supply DIR, a direction, CONF_FUN_0, a confluence function for
1485 blocks with no logical preds (or NULL), CONF_FUN_N, the normal
1486 confluence function, TRANS_FUN, the basic block transfer function,
1487 and BLOCKS, the set of blocks to examine, POSTORDER the blocks in
1488 postorder, and N_BLOCKS, the number of blocks in POSTORDER. */
1489
1490void
1491df_simple_dataflow (enum df_flow_dir dir,
1492 df_init_function init_fun,
1493 df_confluence_function_0 con_fun_0,
1494 df_confluence_function_n con_fun_n,
1495 df_transfer_function trans_fun,
1496 bitmap blocks, int * postorder, int n_blocks)
1497{
1498 memset (&user_problem, 0, sizeof (struct df_problem));
1499 user_problem.dir = dir;
1500 user_problem.init_fun = init_fun;
1501 user_problem.con_fun_0 = con_fun_0;
1502 user_problem.con_fun_n = con_fun_n;
1503 user_problem.trans_fun = trans_fun;
1504 user_dflow.problem = &user_problem;
1505 df_worklist_dataflow (&user_dflow, blocks, postorder, n_blocks);
1506}
1507
1508
1509
1510/*----------------------------------------------------------------------------
1511 Functions to support limited incremental change.
1512----------------------------------------------------------------------------*/
1513
1514
1515/* Get basic block info. */
1516
1517static void *
1518df_get_bb_info (struct dataflow *dflow, unsigned int index)
1519{
1520 if (dflow->block_info == NULL)
1521 return NULL;
1522 if (index >= dflow->block_info_size)
1523 return NULL;
1524 return (void *)((char *)dflow->block_info
1525 + index * dflow->problem->block_info_elt_size);
1526}
1527
1528
1529/* Set basic block info. */
1530
1531static void
1532df_set_bb_info (struct dataflow *dflow, unsigned int index,
1533 void *bb_info)
1534{
1535 gcc_assert (dflow->block_info);
1536 memcpy ((char *)dflow->block_info
1537 + index * dflow->problem->block_info_elt_size,
1538 bb_info, dflow->problem->block_info_elt_size);
1539}
1540
1541
1542/* Clear basic block info. */
1543
1544static void
1545df_clear_bb_info (struct dataflow *dflow, unsigned int index)
1546{
1547 gcc_assert (dflow->block_info);
1548 gcc_assert (dflow->block_info_size > index);
1549 memset ((char *)dflow->block_info
1550 + index * dflow->problem->block_info_elt_size,
1551 0, dflow->problem->block_info_elt_size);
1552}
1553
1554
1555/* Mark the solutions as being out of date. */
1556
1557void
1558df_mark_solutions_dirty (void)
1559{
1560 if (df)
1561 {
1562 int p;
1563 for (p = 1; p < df->num_problems_defined; p++)
1564 df->problems_in_order[p]->solutions_dirty = true;
1565 }
1566}
1567
1568
1569/* Return true if BB needs it's transfer functions recomputed. */
1570
1571bool
1572df_get_bb_dirty (basic_block bb)
1573{
1574 return bitmap_bit_p ((df_live
1575 ? df_live : df_lr)->out_of_date_transfer_functions,
1576 bb->index);
1577}
1578
1579
1580/* Mark BB as needing it's transfer functions as being out of
1581 date. */
1582
1583void
1584df_set_bb_dirty (basic_block bb)
1585{
1586 bb->flags |= BB_MODIFIED;
1587 if (df)
1588 {
1589 int p;
1590 for (p = 1; p < df->num_problems_defined; p++)
1591 {
1592 struct dataflow *dflow = df->problems_in_order[p];
1593 if (dflow->out_of_date_transfer_functions)
1594 bitmap_set_bit (dflow->out_of_date_transfer_functions, bb->index);
1595 }
1596 df_mark_solutions_dirty ();
1597 }
1598}
1599
1600
1601/* Grow the bb_info array. */
1602
1603void
1604df_grow_bb_info (struct dataflow *dflow)
1605{
1606 unsigned int new_size = last_basic_block_for_fn (cfun) + 1;
1607 if (dflow->block_info_size < new_size)
1608 {
1609 new_size += new_size / 4;
1610 dflow->block_info
1611 = (void *)XRESIZEVEC (char, (char *)dflow->block_info,
1612 new_size
1613 * dflow->problem->block_info_elt_size);
1614 memset ((char *)dflow->block_info
1615 + dflow->block_info_size
1616 * dflow->problem->block_info_elt_size,
1617 0,
1618 (new_size - dflow->block_info_size)
1619 * dflow->problem->block_info_elt_size);
1620 dflow->block_info_size = new_size;
1621 }
1622}
1623
1624
1625/* Clear the dirty bits. This is called from places that delete
1626 blocks. */
1627static void
1628df_clear_bb_dirty (basic_block bb)
1629{
1630 int p;
1631 for (p = 1; p < df->num_problems_defined; p++)
1632 {
1633 struct dataflow *dflow = df->problems_in_order[p];
1634 if (dflow->out_of_date_transfer_functions)
1635 bitmap_clear_bit (dflow->out_of_date_transfer_functions, bb->index);
1636 }
1637}
1638
1639/* Called from the rtl_compact_blocks to reorganize the problems basic
1640 block info. */
1641
1642void
1643df_compact_blocks (void)
1644{
1645 int i, p;
1646 basic_block bb;
1647 void *problem_temps;
1648
1649 auto_bitmap tmp (&df_bitmap_obstack);
1650 for (p = 0; p < df->num_problems_defined; p++)
1651 {
1652 struct dataflow *dflow = df->problems_in_order[p];
1653
1654 /* Need to reorganize the out_of_date_transfer_functions for the
1655 dflow problem. */
1656 if (dflow->out_of_date_transfer_functions)
1657 {
1658 bitmap_copy (tmp, dflow->out_of_date_transfer_functions);
1659 bitmap_clear (dflow->out_of_date_transfer_functions);
1660 if (bitmap_bit_p (tmp, ENTRY_BLOCK))
1661 bitmap_set_bit (dflow->out_of_date_transfer_functions, ENTRY_BLOCK);
1662 if (bitmap_bit_p (tmp, EXIT_BLOCK))
1663 bitmap_set_bit (dflow->out_of_date_transfer_functions, EXIT_BLOCK);
1664
1665 i = NUM_FIXED_BLOCKS;
1666 FOR_EACH_BB_FN (bb, cfun)
1667 {
1668 if (bitmap_bit_p (tmp, bb->index))
1669 bitmap_set_bit (dflow->out_of_date_transfer_functions, i);
1670 i++;
1671 }
1672 }
1673
1674 /* Now shuffle the block info for the problem. */
1675 if (dflow->problem->free_bb_fun)
1676 {
1677 int size = (last_basic_block_for_fn (cfun)
1678 * dflow->problem->block_info_elt_size);
1679 problem_temps = XNEWVAR (char, size);
1680 df_grow_bb_info (dflow);
1681 memcpy (problem_temps, dflow->block_info, size);
1682
1683 /* Copy the bb info from the problem tmps to the proper
1684 place in the block_info vector. Null out the copied
1685 item. The entry and exit blocks never move. */
1686 i = NUM_FIXED_BLOCKS;
1687 FOR_EACH_BB_FN (bb, cfun)
1688 {
1689 df_set_bb_info (dflow, i,
1690 (char *)problem_temps
1691 + bb->index * dflow->problem->block_info_elt_size);
1692 i++;
1693 }
1694 memset ((char *)dflow->block_info
1695 + i * dflow->problem->block_info_elt_size, 0,
1696 (last_basic_block_for_fn (cfun) - i)
1697 * dflow->problem->block_info_elt_size);
1698 free (problem_temps);
1699 }
1700 }
1701
1702 /* Shuffle the bits in the basic_block indexed arrays. */
1703
1704 if (df->blocks_to_analyze)
1705 {
1706 if (bitmap_bit_p (tmp, ENTRY_BLOCK))
1707 bitmap_set_bit (df->blocks_to_analyze, ENTRY_BLOCK);
1708 if (bitmap_bit_p (tmp, EXIT_BLOCK))
1709 bitmap_set_bit (df->blocks_to_analyze, EXIT_BLOCK);
1710 bitmap_copy (tmp, df->blocks_to_analyze);
1711 bitmap_clear (df->blocks_to_analyze);
1712 i = NUM_FIXED_BLOCKS;
1713 FOR_EACH_BB_FN (bb, cfun)
1714 {
1715 if (bitmap_bit_p (tmp, bb->index))
1716 bitmap_set_bit (df->blocks_to_analyze, i);
1717 i++;
1718 }
1719 }
1720
1721 i = NUM_FIXED_BLOCKS;
1722 FOR_EACH_BB_FN (bb, cfun)
1723 {
1724 SET_BASIC_BLOCK_FOR_FN (cfun, i, bb);
1725 bb->index = i;
1726 i++;
1727 }
1728
1729 gcc_assert (i == n_basic_blocks_for_fn (cfun));
1730
1731 for (; i < last_basic_block_for_fn (cfun); i++)
1732 SET_BASIC_BLOCK_FOR_FN (cfun, i, NULL);
1733
1734#ifdef DF_DEBUG_CFG
1735 if (!df_lr->solutions_dirty)
1736 df_set_clean_cfg ();
1737#endif
1738}
1739
1740
1741/* Shove NEW_BLOCK in at OLD_INDEX. Called from ifcvt to hack a
1742 block. There is no excuse for people to do this kind of thing. */
1743
1744void
1745df_bb_replace (int old_index, basic_block new_block)
1746{
1747 int new_block_index = new_block->index;
1748 int p;
1749
1750 if (dump_file)
1751 fprintf (dump_file, "shoving block %d into %d\n", new_block_index, old_index);
1752
1753 gcc_assert (df);
1754 gcc_assert (BASIC_BLOCK_FOR_FN (cfun, old_index) == NULL);
1755
1756 for (p = 0; p < df->num_problems_defined; p++)
1757 {
1758 struct dataflow *dflow = df->problems_in_order[p];
1759 if (dflow->block_info)
1760 {
1761 df_grow_bb_info (dflow);
1762 df_set_bb_info (dflow, old_index,
1763 df_get_bb_info (dflow, new_block_index));
1764 }
1765 }
1766
1767 df_clear_bb_dirty (new_block);
1768 SET_BASIC_BLOCK_FOR_FN (cfun, old_index, new_block);
1769 new_block->index = old_index;
1770 df_set_bb_dirty (BASIC_BLOCK_FOR_FN (cfun, old_index));
1771 SET_BASIC_BLOCK_FOR_FN (cfun, new_block_index, NULL);
1772}
1773
1774
1775/* Free all of the per basic block dataflow from all of the problems.
1776 This is typically called before a basic block is deleted and the
1777 problem will be reanalyzed. */
1778
1779void
1780df_bb_delete (int bb_index)
1781{
1782 basic_block bb = BASIC_BLOCK_FOR_FN (cfun, bb_index);
1783 int i;
1784
1785 if (!df)
1786 return;
1787
1788 for (i = 0; i < df->num_problems_defined; i++)
1789 {
1790 struct dataflow *dflow = df->problems_in_order[i];
1791 if (dflow->problem->free_bb_fun)
1792 {
1793 void *bb_info = df_get_bb_info (dflow, bb_index);
1794 if (bb_info)
1795 {
1796 dflow->problem->free_bb_fun (bb, bb_info);
1797 df_clear_bb_info (dflow, bb_index);
1798 }
1799 }
1800 }
1801 df_clear_bb_dirty (bb);
1802 df_mark_solutions_dirty ();
1803}
1804
1805
1806/* Verify that there is a place for everything and everything is in
1807 its place. This is too expensive to run after every pass in the
1808 mainline. However this is an excellent debugging tool if the
1809 dataflow information is not being updated properly. You can just
1810 sprinkle calls in until you find the place that is changing an
1811 underlying structure without calling the proper updating
1812 routine. */
1813
1814void
1815df_verify (void)
1816{
1817 df_scan_verify ();
1818#ifdef ENABLE_DF_CHECKING
1819 df_lr_verify_transfer_functions ();
1820 if (df_live)
1821 df_live_verify_transfer_functions ();
1822#endif
1823 df->changeable_flags &= ~DF_VERIFY_SCHEDULED;
1824}
1825
1826#ifdef DF_DEBUG_CFG
1827
1828/* Compute an array of ints that describes the cfg. This can be used
1829 to discover places where the cfg is modified by the appropriate
1830 calls have not been made to the keep df informed. The internals of
1831 this are unexciting, the key is that two instances of this can be
1832 compared to see if any changes have been made to the cfg. */
1833
1834static int *
1835df_compute_cfg_image (void)
1836{
1837 basic_block bb;
1838 int size = 2 + (2 * n_basic_blocks_for_fn (cfun));
1839 int i;
1840 int * map;
1841
1842 FOR_ALL_BB_FN (bb, cfun)
1843 {
1844 size += EDGE_COUNT (bb->succs);
1845 }
1846
1847 map = XNEWVEC (int, size);
1848 map[0] = size;
1849 i = 1;
1850 FOR_ALL_BB_FN (bb, cfun)
1851 {
1852 edge_iterator ei;
1853 edge e;
1854
1855 map[i++] = bb->index;
1856 FOR_EACH_EDGE (e, ei, bb->succs)
1857 map[i++] = e->dest->index;
1858 map[i++] = -1;
1859 }
1860 map[i] = -1;
1861 return map;
1862}
1863
1864static int *saved_cfg = NULL;
1865
1866
1867/* This function compares the saved version of the cfg with the
1868 current cfg and aborts if the two are identical. The function
1869 silently returns if the cfg has been marked as dirty or the two are
1870 the same. */
1871
1872void
1873df_check_cfg_clean (void)
1874{
1875 int *new_map;
1876
1877 if (!df)
1878 return;
1879
1880 if (df_lr->solutions_dirty)
1881 return;
1882
1883 if (saved_cfg == NULL)
1884 return;
1885
1886 new_map = df_compute_cfg_image ();
1887 gcc_assert (memcmp (saved_cfg, new_map, saved_cfg[0] * sizeof (int)) == 0);
1888 free (new_map);
1889}
1890
1891
1892/* This function builds a cfg fingerprint and squirrels it away in
1893 saved_cfg. */
1894
1895static void
1896df_set_clean_cfg (void)
1897{
1898 free (saved_cfg);
1899 saved_cfg = df_compute_cfg_image ();
1900}
1901
1902#endif /* DF_DEBUG_CFG */
1903/*----------------------------------------------------------------------------
1904 PUBLIC INTERFACES TO QUERY INFORMATION.
1905----------------------------------------------------------------------------*/
1906
1907
1908/* Return first def of REGNO within BB. */
1909
1910df_ref
1911df_bb_regno_first_def_find (basic_block bb, unsigned int regno)
1912{
1913 rtx_insn *insn;
1914 df_ref def;
1915
1916 FOR_BB_INSNS (bb, insn)
1917 {
1918 if (!INSN_P (insn))
1919 continue;
1920
1921 FOR_EACH_INSN_DEF (def, insn)
1922 if (DF_REF_REGNO (def) == regno)
1923 return def;
1924 }
1925 return NULL;
1926}
1927
1928
1929/* Return last def of REGNO within BB. */
1930
1931df_ref
1932df_bb_regno_last_def_find (basic_block bb, unsigned int regno)
1933{
1934 rtx_insn *insn;
1935 df_ref def;
1936
1937 FOR_BB_INSNS_REVERSE (bb, insn)
1938 {
1939 if (!INSN_P (insn))
1940 continue;
1941
1942 FOR_EACH_INSN_DEF (def, insn)
1943 if (DF_REF_REGNO (def) == regno)
1944 return def;
1945 }
1946
1947 return NULL;
1948}
1949
1950/* Finds the reference corresponding to the definition of REG in INSN.
1951 DF is the dataflow object. */
1952
1953df_ref
1954df_find_def (rtx_insn *insn, rtx reg)
1955{
1956 df_ref def;
1957
1958 if (GET_CODE (reg) == SUBREG)
1959 reg = SUBREG_REG (reg);
1960 gcc_assert (REG_P (reg));
1961
1962 FOR_EACH_INSN_DEF (def, insn)
1963 if (DF_REF_REGNO (def) == REGNO (reg))
1964 return def;
1965
1966 return NULL;
1967}
1968
1969
1970/* Return true if REG is defined in INSN, zero otherwise. */
1971
1972bool
1973df_reg_defined (rtx_insn *insn, rtx reg)
1974{
1975 return df_find_def (insn, reg) != NULL;
1976}
1977
1978
1979/* Finds the reference corresponding to the use of REG in INSN.
1980 DF is the dataflow object. */
1981
1982df_ref
1983df_find_use (rtx_insn *insn, rtx reg)
1984{
1985 df_ref use;
1986
1987 if (GET_CODE (reg) == SUBREG)
1988 reg = SUBREG_REG (reg);
1989 gcc_assert (REG_P (reg));
1990
1991 df_insn_info *insn_info = DF_INSN_INFO_GET (insn);
1992 FOR_EACH_INSN_INFO_USE (use, insn_info)
1993 if (DF_REF_REGNO (use) == REGNO (reg))
1994 return use;
1995 if (df->changeable_flags & DF_EQ_NOTES)
1996 FOR_EACH_INSN_INFO_EQ_USE (use, insn_info)
1997 if (DF_REF_REGNO (use) == REGNO (reg))
1998 return use;
1999 return NULL;
2000}
2001
2002
2003/* Return true if REG is referenced in INSN, zero otherwise. */
2004
2005bool
2006df_reg_used (rtx_insn *insn, rtx reg)
2007{
2008 return df_find_use (insn, reg) != NULL;
2009}
2010
2011
2012/*----------------------------------------------------------------------------
2013 Debugging and printing functions.
2014----------------------------------------------------------------------------*/
2015
2016/* Write information about registers and basic blocks into FILE.
2017 This is part of making a debugging dump. */
2018
2019void
2020dump_regset (regset r, FILE *outf)
2021{
2022 unsigned i;
2023 reg_set_iterator rsi;
2024
2025 if (r == NULL)
2026 {
2027 fputs (" (nil)", outf);
2028 return;
2029 }
2030
2031 EXECUTE_IF_SET_IN_REG_SET (r, 0, i, rsi)
2032 {
2033 fprintf (outf, " %d", i);
2034 if (i < FIRST_PSEUDO_REGISTER)
2035 fprintf (outf, " [%s]",
2036 reg_names[i]);
2037 }
2038}
2039
2040/* Print a human-readable representation of R on the standard error
2041 stream. This function is designed to be used from within the
2042 debugger. */
2043extern void debug_regset (regset);
2044DEBUG_FUNCTION void
2045debug_regset (regset r)
2046{
2047 dump_regset (r, stderr);
2048 putc ('\n', stderr);
2049}
2050
2051/* Write information about registers and basic blocks into FILE.
2052 This is part of making a debugging dump. */
2053
2054void
2055df_print_regset (FILE *file, bitmap r)
2056{
2057 unsigned int i;
2058 bitmap_iterator bi;
2059
2060 if (r == NULL)
2061 fputs (" (nil)", file);
2062 else
2063 {
2064 EXECUTE_IF_SET_IN_BITMAP (r, 0, i, bi)
2065 {
2066 fprintf (file, " %d", i);
2067 if (i < FIRST_PSEUDO_REGISTER)
2068 fprintf (file, " [%s]", reg_names[i]);
2069 }
2070 }
2071 fprintf (file, "\n");
2072}
2073
2074
2075/* Write information about registers and basic blocks into FILE. The
2076 bitmap is in the form used by df_byte_lr. This is part of making a
2077 debugging dump. */
2078
2079void
2080df_print_word_regset (FILE *file, bitmap r)
2081{
2082 unsigned int max_reg = max_reg_num ();
2083
2084 if (r == NULL)
2085 fputs (" (nil)", file);
2086 else
2087 {
2088 unsigned int i;
2089 for (i = FIRST_PSEUDO_REGISTER; i < max_reg; i++)
2090 {
2091 bool found = (bitmap_bit_p (r, 2 * i)
2092 || bitmap_bit_p (r, 2 * i + 1));
2093 if (found)
2094 {
2095 int word;
2096 const char * sep = "";
2097 fprintf (file, " %d", i);
2098 fprintf (file, "(");
2099 for (word = 0; word < 2; word++)
2100 if (bitmap_bit_p (r, 2 * i + word))
2101 {
2102 fprintf (file, "%s%d", sep, word);
2103 sep = ", ";
2104 }
2105 fprintf (file, ")");
2106 }
2107 }
2108 }
2109 fprintf (file, "\n");
2110}
2111
2112
2113/* Dump dataflow info. */
2114
2115void
2116df_dump (FILE *file)
2117{
2118 basic_block bb;
2119 df_dump_start (file);
2120
2121 FOR_ALL_BB_FN (bb, cfun)
2122 {
2123 df_print_bb_index (bb, file);
2124 df_dump_top (bb, file);
2125 df_dump_bottom (bb, file);
2126 }
2127
2128 fprintf (file, "\n");
2129}
2130
2131
2132/* Dump dataflow info for df->blocks_to_analyze. */
2133
2134void
2135df_dump_region (FILE *file)
2136{
2137 if (df->blocks_to_analyze)
2138 {
2139 bitmap_iterator bi;
2140 unsigned int bb_index;
2141
2142 fprintf (file, "\n\nstarting region dump\n");
2143 df_dump_start (file);
2144
2145 EXECUTE_IF_SET_IN_BITMAP (df->blocks_to_analyze, 0, bb_index, bi)
2146 {
2147 basic_block bb = BASIC_BLOCK_FOR_FN (cfun, bb_index);
2148 dump_bb (file, bb, 0, TDF_DETAILS);
2149 }
2150 fprintf (file, "\n");
2151 }
2152 else
2153 df_dump (file);
2154}
2155
2156
2157/* Dump the introductory information for each problem defined. */
2158
2159void
2160df_dump_start (FILE *file)
2161{
2162 int i;
2163
2164 if (!df || !file)
2165 return;
2166
2167 fprintf (file, "\n\n%s\n", current_function_name ());
2168 fprintf (file, "\nDataflow summary:\n");
2169 if (df->blocks_to_analyze)
2170 fprintf (file, "def_info->table_size = %d, use_info->table_size = %d\n",
2171 DF_DEFS_TABLE_SIZE (), DF_USES_TABLE_SIZE ());
2172
2173 for (i = 0; i < df->num_problems_defined; i++)
2174 {
2175 struct dataflow *dflow = df->problems_in_order[i];
2176 if (dflow->computed)
2177 {
2178 df_dump_problem_function fun = dflow->problem->dump_start_fun;
2179 if (fun)
2180 fun (file);
2181 }
2182 }
2183}
2184
2185
2186/* Dump the top or bottom of the block information for BB. */
2187static void
2188df_dump_bb_problem_data (basic_block bb, FILE *file, bool top)
2189{
2190 int i;
2191
2192 if (!df || !file)
2193 return;
2194
2195 for (i = 0; i < df->num_problems_defined; i++)
2196 {
2197 struct dataflow *dflow = df->problems_in_order[i];
2198 if (dflow->computed)
2199 {
2200 df_dump_bb_problem_function bbfun;
2201
2202 if (top)
2203 bbfun = dflow->problem->dump_top_fun;
2204 else
2205 bbfun = dflow->problem->dump_bottom_fun;
2206
2207 if (bbfun)
2208 bbfun (bb, file);
2209 }
2210 }
2211}
2212
2213/* Dump the top of the block information for BB. */
2214
2215void
2216df_dump_top (basic_block bb, FILE *file)
2217{
2218 df_dump_bb_problem_data (bb, file, /*top=*/true);
2219}
2220
2221/* Dump the bottom of the block information for BB. */
2222
2223void
2224df_dump_bottom (basic_block bb, FILE *file)
2225{
2226 df_dump_bb_problem_data (bb, file, /*top=*/false);
2227}
2228
2229
2230/* Dump information about INSN just before or after dumping INSN itself. */
2231static void
2232df_dump_insn_problem_data (const rtx_insn *insn, FILE *file, bool top)
2233{
2234 int i;
2235
2236 if (!df || !file)
2237 return;
2238
2239 for (i = 0; i < df->num_problems_defined; i++)
2240 {
2241 struct dataflow *dflow = df->problems_in_order[i];
2242 if (dflow->computed)
2243 {
2244 df_dump_insn_problem_function insnfun;
2245
2246 if (top)
2247 insnfun = dflow->problem->dump_insn_top_fun;
2248 else
2249 insnfun = dflow->problem->dump_insn_bottom_fun;
2250
2251 if (insnfun)
2252 insnfun (insn, file);
2253 }
2254 }
2255}
2256
2257/* Dump information about INSN before dumping INSN itself. */
2258
2259void
2260df_dump_insn_top (const rtx_insn *insn, FILE *file)
2261{
2262 df_dump_insn_problem_data (insn, file, /*top=*/true);
2263}
2264
2265/* Dump information about INSN after dumping INSN itself. */
2266
2267void
2268df_dump_insn_bottom (const rtx_insn *insn, FILE *file)
2269{
2270 df_dump_insn_problem_data (insn, file, /*top=*/false);
2271}
2272
2273
2274static void
2275df_ref_dump (df_ref ref, FILE *file)
2276{
2277 fprintf (file, "%c%d(%d)",
2278 DF_REF_REG_DEF_P (ref)
2279 ? 'd'
2280 : (DF_REF_FLAGS (ref) & DF_REF_IN_NOTE) ? 'e' : 'u',
2281 DF_REF_ID (ref),
2282 DF_REF_REGNO (ref));
2283}
2284
2285void
2286df_refs_chain_dump (df_ref ref, bool follow_chain, FILE *file)
2287{
2288 fprintf (file, "{ ");
2289 for (; ref; ref = DF_REF_NEXT_LOC (ref))
2290 {
2291 df_ref_dump (ref, file);
2292 if (follow_chain)
2293 df_chain_dump (DF_REF_CHAIN (ref), file);
2294 }
2295 fprintf (file, "}");
2296}
2297
2298
2299/* Dump either a ref-def or reg-use chain. */
2300
2301void
2302df_regs_chain_dump (df_ref ref, FILE *file)
2303{
2304 fprintf (file, "{ ");
2305 while (ref)
2306 {
2307 df_ref_dump (ref, file);
2308 ref = DF_REF_NEXT_REG (ref);
2309 }
2310 fprintf (file, "}");
2311}
2312
2313
2314static void
2315df_mws_dump (struct df_mw_hardreg *mws, FILE *file)
2316{
2317 for (; mws; mws = DF_MWS_NEXT (mws))
2318 fprintf (file, "mw %c r[%d..%d]\n",
2319 DF_MWS_REG_DEF_P (mws) ? 'd' : 'u',
2320 mws->start_regno, mws->end_regno);
2321}
2322
2323
2324static void
2325df_insn_uid_debug (unsigned int uid,
2326 bool follow_chain, FILE *file)
2327{
2328 fprintf (file, "insn %d luid %d",
2329 uid, DF_INSN_UID_LUID (uid));
2330
2331 if (DF_INSN_UID_DEFS (uid))
2332 {
2333 fprintf (file, " defs ");
2334 df_refs_chain_dump (DF_INSN_UID_DEFS (uid), follow_chain, file);
2335 }
2336
2337 if (DF_INSN_UID_USES (uid))
2338 {
2339 fprintf (file, " uses ");
2340 df_refs_chain_dump (DF_INSN_UID_USES (uid), follow_chain, file);
2341 }
2342
2343 if (DF_INSN_UID_EQ_USES (uid))
2344 {
2345 fprintf (file, " eq uses ");
2346 df_refs_chain_dump (DF_INSN_UID_EQ_USES (uid), follow_chain, file);
2347 }
2348
2349 if (DF_INSN_UID_MWS (uid))
2350 {
2351 fprintf (file, " mws ");
2352 df_mws_dump (DF_INSN_UID_MWS (uid), file);
2353 }
2354 fprintf (file, "\n");
2355}
2356
2357
2358DEBUG_FUNCTION void
2359df_insn_debug (rtx_insn *insn, bool follow_chain, FILE *file)
2360{
2361 df_insn_uid_debug (INSN_UID (insn), follow_chain, file);
2362}
2363
2364DEBUG_FUNCTION void
2365df_insn_debug_regno (rtx_insn *insn, FILE *file)
2366{
2367 struct df_insn_info *insn_info = DF_INSN_INFO_GET (insn);
2368
2369 fprintf (file, "insn %d bb %d luid %d defs ",
2370 INSN_UID (insn), BLOCK_FOR_INSN (insn)->index,
2371 DF_INSN_INFO_LUID (insn_info));
2372 df_refs_chain_dump (DF_INSN_INFO_DEFS (insn_info), false, file);
2373
2374 fprintf (file, " uses ");
2375 df_refs_chain_dump (DF_INSN_INFO_USES (insn_info), false, file);
2376
2377 fprintf (file, " eq_uses ");
2378 df_refs_chain_dump (DF_INSN_INFO_EQ_USES (insn_info), false, file);
2379 fprintf (file, "\n");
2380}
2381
2382DEBUG_FUNCTION void
2383df_regno_debug (unsigned int regno, FILE *file)
2384{
2385 fprintf (file, "reg %d defs ", regno);
2386 df_regs_chain_dump (DF_REG_DEF_CHAIN (regno), file);
2387 fprintf (file, " uses ");
2388 df_regs_chain_dump (DF_REG_USE_CHAIN (regno), file);
2389 fprintf (file, " eq_uses ");
2390 df_regs_chain_dump (DF_REG_EQ_USE_CHAIN (regno), file);
2391 fprintf (file, "\n");
2392}
2393
2394
2395DEBUG_FUNCTION void
2396df_ref_debug (df_ref ref, FILE *file)
2397{
2398 fprintf (file, "%c%d ",
2399 DF_REF_REG_DEF_P (ref) ? 'd' : 'u',
2400 DF_REF_ID (ref));
2401 fprintf (file, "reg %d bb %d insn %d flag %#x type %#x ",
2402 DF_REF_REGNO (ref),
2403 DF_REF_BBNO (ref),
2404 DF_REF_IS_ARTIFICIAL (ref) ? -1 : DF_REF_INSN_UID (ref),
2405 DF_REF_FLAGS (ref),
2406 DF_REF_TYPE (ref));
2407 if (DF_REF_LOC (ref))
2408 {
2409 if (flag_dump_noaddr)
2410 fprintf (file, "loc #(#) chain ");
2411 else
2412 fprintf (file, "loc %p(%p) chain ", (void *)DF_REF_LOC (ref),
2413 (void *)*DF_REF_LOC (ref));
2414 }
2415 else
2416 fprintf (file, "chain ");
2417 df_chain_dump (DF_REF_CHAIN (ref), file);
2418 fprintf (file, "\n");
2419}
2420
2421/* Functions for debugging from GDB. */
2422
2423DEBUG_FUNCTION void
2424debug_df_insn (rtx_insn *insn)
2425{
2426 df_insn_debug (insn, true, stderr);
2427 debug_rtx (insn);
2428}
2429
2430
2431DEBUG_FUNCTION void
2432debug_df_reg (rtx reg)
2433{
2434 df_regno_debug (REGNO (reg), stderr);
2435}
2436
2437
2438DEBUG_FUNCTION void
2439debug_df_regno (unsigned int regno)
2440{
2441 df_regno_debug (regno, stderr);
2442}
2443
2444
2445DEBUG_FUNCTION void
2446debug_df_ref (df_ref ref)
2447{
2448 df_ref_debug (ref, stderr);
2449}
2450
2451
2452DEBUG_FUNCTION void
2453debug_df_defno (unsigned int defno)
2454{
2455 df_ref_debug (DF_DEFS_GET (defno), stderr);
2456}
2457
2458
2459DEBUG_FUNCTION void
2460debug_df_useno (unsigned int defno)
2461{
2462 df_ref_debug (DF_USES_GET (defno), stderr);
2463}
2464
2465
2466DEBUG_FUNCTION void
2467debug_df_chain (struct df_link *link)
2468{
2469 df_chain_dump (link, stderr);
2470 fputc ('\n', stderr);
2471}
2472