1/* Instruction scheduling pass.  This file contains definitions used
2   internally in the scheduler.
3   Copyright (C) 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999, 2000,
4   2001, 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010
5   Free Software Foundation, Inc.
6
7This file is part of GCC.
8
9GCC is free software; you can redistribute it and/or modify it under
10the terms of the GNU General Public License as published by the Free
11Software Foundation; either version 3, or (at your option) any later
12version.
13
14GCC is distributed in the hope that it will be useful, but WITHOUT ANY
15WARRANTY; without even the implied warranty of MERCHANTABILITY or
16FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
17for more details.
18
19You should have received a copy of the GNU General Public License
20along with GCC; see the file COPYING3.  If not see
21<http://www.gnu.org/licenses/>.  */
22
23#ifndef GCC_SCHED_INT_H
24#define GCC_SCHED_INT_H
25
26#ifdef INSN_SCHEDULING
27
28/* For state_t.  */
29#include "insn-attr.h"
30#include "df.h"
31#include "basic-block.h"
32
33/* For VEC (int, heap).  */
34#include "vecprim.h"
35
36/* Identificator of a scheduler pass.  */
37enum sched_pass_id_t { SCHED_PASS_UNKNOWN, SCHED_RGN_PASS, SCHED_EBB_PASS,
38		       SCHED_SMS_PASS, SCHED_SEL_PASS };
39
40typedef VEC (basic_block, heap) *bb_vec_t;
41typedef VEC (rtx, heap) *insn_vec_t;
42typedef VEC(rtx, heap) *rtx_vec_t;
43
44struct sched_scan_info_def
45{
46  /* This hook notifies scheduler frontend to extend its internal per basic
47     block data structures.  This hook should be called once before a series of
48     calls to bb_init ().  */
49  void (*extend_bb) (void);
50
51  /* This hook makes scheduler frontend to initialize its internal data
52     structures for the passed basic block.  */
53  void (*init_bb) (basic_block);
54
55  /* This hook notifies scheduler frontend to extend its internal per insn data
56     structures.  This hook should be called once before a series of calls to
57     insn_init ().  */
58  void (*extend_insn) (void);
59
60  /* This hook makes scheduler frontend to initialize its internal data
61     structures for the passed insn.  */
62  void (*init_insn) (rtx);
63};
64
65extern const struct sched_scan_info_def *sched_scan_info;
66
67extern void sched_scan (const struct sched_scan_info_def *,
68			bb_vec_t, basic_block, insn_vec_t, rtx);
69
70extern void sched_init_bbs (void);
71
72extern void sched_init_luids (bb_vec_t, basic_block, insn_vec_t, rtx);
73extern void sched_finish_luids (void);
74
75extern void sched_extend_target (void);
76
77extern void haifa_init_h_i_d (bb_vec_t, basic_block, insn_vec_t, rtx);
78extern void haifa_finish_h_i_d (void);
79
80/* Hooks that are common to all the schedulers.  */
81struct common_sched_info_def
82{
83  /* Called after blocks were rearranged due to movement of jump instruction.
84     The first parameter - index of basic block, in which jump currently is.
85     The second parameter - index of basic block, in which jump used
86     to be.
87     The third parameter - index of basic block, that follows the second
88     parameter.  */
89  void (*fix_recovery_cfg) (int, int, int);
90
91  /* Called to notify frontend, that new basic block is being added.
92     The first parameter - new basic block.
93     The second parameter - block, after which new basic block is being added,
94     or EXIT_BLOCK_PTR, if recovery block is being added,
95     or NULL, if standalone block is being added.  */
96  void (*add_block) (basic_block, basic_block);
97
98  /* Estimate number of insns in the basic block.  */
99  int (*estimate_number_of_insns) (basic_block);
100
101  /* Given a non-insn (!INSN_P (x)) return
102     -1 - if this rtx don't need a luid.
103     0 - if it should have the same luid as the previous insn.
104     1 - if it needs a separate luid.  */
105  int (*luid_for_non_insn) (rtx);
106
107  /* Scheduler pass identifier.  It is preferably used in assertions.  */
108  enum sched_pass_id_t sched_pass_id;
109};
110
111extern struct common_sched_info_def *common_sched_info;
112
113extern const struct common_sched_info_def haifa_common_sched_info;
114
115/* Return true if selective scheduling pass is working.  */
116static inline bool
117sel_sched_p (void)
118{
119  return common_sched_info->sched_pass_id == SCHED_SEL_PASS;
120}
121
122/* Returns maximum priority that an insn was assigned to.  */
123extern int get_rgn_sched_max_insns_priority (void);
124
125/* Increases effective priority for INSN by AMOUNT.  */
126extern void sel_add_to_insn_priority (rtx, int);
127
128/* True if during selective scheduling we need to emulate some of haifa
129   scheduler behaviour.  */
130extern int sched_emulate_haifa_p;
131
132/* Mapping from INSN_UID to INSN_LUID.  In the end all other per insn data
133   structures should be indexed by luid.  */
134extern VEC (int, heap) *sched_luids;
135#define INSN_LUID(INSN) (VEC_index (int, sched_luids, INSN_UID (INSN)))
136#define LUID_BY_UID(UID) (VEC_index (int, sched_luids, UID))
137
138#define SET_INSN_LUID(INSN, LUID) \
139(VEC_replace (int, sched_luids, INSN_UID (INSN), (LUID)))
140
141/* The highest INSN_LUID.  */
142extern int sched_max_luid;
143
144extern int insn_luid (rtx);
145
146/* This list holds ripped off notes from the current block.  These notes will
147   be attached to the beginning of the block when its scheduling is
148   finished.  */
149extern rtx note_list;
150
151extern void remove_notes (rtx, rtx);
152extern rtx restore_other_notes (rtx, basic_block);
153extern void sched_insns_init (rtx);
154extern void sched_insns_finish (void);
155
156extern void *xrecalloc (void *, size_t, size_t, size_t);
157extern rtx bb_note (basic_block);
158
159extern void reemit_notes (rtx);
160
161/* Functions in haifa-sched.c.  */
162extern int haifa_classify_insn (const_rtx);
163
164/* Functions in sel-sched-ir.c.  */
165extern void sel_find_rgns (void);
166extern void sel_mark_hard_insn (rtx);
167
168extern size_t dfa_state_size;
169
170extern void advance_state (state_t);
171
172extern void setup_sched_dump (void);
173extern void sched_init (void);
174extern void sched_finish (void);
175
176extern bool sel_insn_is_speculation_check (rtx);
177
178/* Describe the ready list of the scheduler.
179   VEC holds space enough for all insns in the current region.  VECLEN
180   says how many exactly.
181   FIRST is the index of the element with the highest priority; i.e. the
182   last one in the ready list, since elements are ordered by ascending
183   priority.
184   N_READY determines how many insns are on the ready list.
185   N_DEBUG determines how many debug insns are on the ready list.  */
186struct ready_list
187{
188  rtx *vec;
189  int veclen;
190  int first;
191  int n_ready;
192  int n_debug;
193};
194
195extern char *ready_try;
196extern struct ready_list ready;
197
198extern int max_issue (struct ready_list *, int, state_t, int *);
199
200extern void ebb_compute_jump_reg_dependencies (rtx, regset, regset, regset);
201
202extern edge find_fallthru_edge (basic_block);
203
204extern void (* sched_init_only_bb) (basic_block, basic_block);
205extern basic_block (* sched_split_block) (basic_block, rtx);
206extern basic_block sched_split_block_1 (basic_block, rtx);
207extern basic_block (* sched_create_empty_bb) (basic_block);
208extern basic_block sched_create_empty_bb_1 (basic_block);
209
210extern basic_block sched_create_recovery_block (basic_block *);
211extern void sched_create_recovery_edges (basic_block, basic_block,
212					 basic_block);
213
214/* Pointer to data describing the current DFA state.  */
215extern state_t curr_state;
216
217/* Type to represent status of a dependence.  */
218typedef int ds_t;
219
220/* Type to represent weakness of speculative dependence.  */
221typedef int dw_t;
222
223extern enum reg_note ds_to_dk (ds_t);
224extern ds_t dk_to_ds (enum reg_note);
225
226/* Information about the dependency.  */
227struct _dep
228{
229  /* Producer.  */
230  rtx pro;
231
232  /* Consumer.  */
233  rtx con;
234
235  /* Dependency major type.  This field is superseded by STATUS below.
236     Though, it is still in place because some targets use it.  */
237  enum reg_note type;
238
239  /* Dependency status.  This field holds all dependency types and additional
240     information for speculative dependencies.  */
241  ds_t status;
242};
243
244typedef struct _dep dep_def;
245typedef dep_def *dep_t;
246
247#define DEP_PRO(D) ((D)->pro)
248#define DEP_CON(D) ((D)->con)
249#define DEP_TYPE(D) ((D)->type)
250#define DEP_STATUS(D) ((D)->status)
251
252/* Functions to work with dep.  */
253
254extern void init_dep_1 (dep_t, rtx, rtx, enum reg_note, ds_t);
255extern void init_dep (dep_t, rtx, rtx, enum reg_note);
256
257extern void sd_debug_dep (dep_t);
258
259/* Definition of this struct resides below.  */
260struct _dep_node;
261typedef struct _dep_node *dep_node_t;
262
263/* A link in the dependency list.  This is essentially an equivalent of a
264   single {INSN, DEPS}_LIST rtx.  */
265struct _dep_link
266{
267  /* Dep node with all the data.  */
268  dep_node_t node;
269
270  /* Next link in the list. For the last one it is NULL.  */
271  struct _dep_link *next;
272
273  /* Pointer to the next field of the previous link in the list.
274     For the first link this points to the deps_list->first.
275
276     With help of this field it is easy to remove and insert links to the
277     list.  */
278  struct _dep_link **prev_nextp;
279};
280typedef struct _dep_link *dep_link_t;
281
282#define DEP_LINK_NODE(N) ((N)->node)
283#define DEP_LINK_NEXT(N) ((N)->next)
284#define DEP_LINK_PREV_NEXTP(N) ((N)->prev_nextp)
285
286/* Macros to work dep_link.  For most usecases only part of the dependency
287   information is need.  These macros conveniently provide that piece of
288   information.  */
289
290#define DEP_LINK_DEP(N) (DEP_NODE_DEP (DEP_LINK_NODE (N)))
291#define DEP_LINK_PRO(N) (DEP_PRO (DEP_LINK_DEP (N)))
292#define DEP_LINK_CON(N) (DEP_CON (DEP_LINK_DEP (N)))
293#define DEP_LINK_TYPE(N) (DEP_TYPE (DEP_LINK_DEP (N)))
294#define DEP_LINK_STATUS(N) (DEP_STATUS (DEP_LINK_DEP (N)))
295
296/* A list of dep_links.  */
297struct _deps_list
298{
299  /* First element.  */
300  dep_link_t first;
301
302  /* Total number of elements in the list.  */
303  int n_links;
304};
305typedef struct _deps_list *deps_list_t;
306
307#define DEPS_LIST_FIRST(L) ((L)->first)
308#define DEPS_LIST_N_LINKS(L) ((L)->n_links)
309
310/* Suppose we have a dependence Y between insn pro1 and con1, where pro1 has
311   additional dependents con0 and con2, and con1 is dependent on additional
312   insns pro0 and pro1:
313
314   .con0      pro0
315   . ^         |
316   . |         |
317   . |         |
318   . X         A
319   . |         |
320   . |         |
321   . |         V
322   .pro1--Y-->con1
323   . |         ^
324   . |         |
325   . |         |
326   . Z         B
327   . |         |
328   . |         |
329   . V         |
330   .con2      pro2
331
332   This is represented using a "dep_node" for each dependence arc, which are
333   connected as follows (diagram is centered around Y which is fully shown;
334   other dep_nodes shown partially):
335
336   .          +------------+    +--------------+    +------------+
337   .          : dep_node X :    |  dep_node Y  |    : dep_node Z :
338   .          :            :    |              |    :            :
339   .          :            :    |              |    :            :
340   .          : forw       :    |  forw        |    : forw       :
341   .          : +--------+ :    |  +--------+  |    : +--------+ :
342   forw_deps  : |dep_link| :    |  |dep_link|  |    : |dep_link| :
343   +-----+    : | +----+ | :    |  | +----+ |  |    : | +----+ | :
344   |first|----->| |next|-+------+->| |next|-+--+----->| |next|-+--->NULL
345   +-----+    : | +----+ | :    |  | +----+ |  |    : | +----+ | :
346   . ^  ^     : |     ^  | :    |  |     ^  |  |    : |        | :
347   . |  |     : |     |  | :    |  |     |  |  |    : |        | :
348   . |  +--<----+--+  +--+---<--+--+--+  +--+--+--<---+--+     | :
349   . |        : |  |     | :    |  |  |     |  |    : |  |     | :
350   . |        : | +----+ | :    |  | +----+ |  |    : | +----+ | :
351   . |        : | |prev| | :    |  | |prev| |  |    : | |prev| | :
352   . |        : | |next| | :    |  | |next| |  |    : | |next| | :
353   . |        : | +----+ | :    |  | +----+ |  |    : | +----+ | :
354   . |        : |        | :<-+ |  |        |  |<-+ : |        | :<-+
355   . |        : | +----+ | :  | |  | +----+ |  |  | : | +----+ | :  |
356   . |        : | |node|-+----+ |  | |node|-+--+--+ : | |node|-+----+
357   . |        : | +----+ | :    |  | +----+ |  |    : | +----+ | :
358   . |        : |        | :    |  |        |  |    : |        | :
359   . |        : +--------+ :    |  +--------+  |    : +--------+ :
360   . |        :            :    |              |    :            :
361   . |        :  SAME pro1 :    |  +--------+  |    :  SAME pro1 :
362   . |        :  DIFF con0 :    |  |dep     |  |    :  DIFF con2 :
363   . |        :            :    |  |        |  |    :            :
364   . |                          |  | +----+ |  |
365   .RTX<------------------------+--+-|pro1| |  |
366   .pro1                        |  | +----+ |  |
367   .                            |  |        |  |
368   .                            |  | +----+ |  |
369   .RTX<------------------------+--+-|con1| |  |
370   .con1                        |  | +----+ |  |
371   . |                          |  |        |  |
372   . |                          |  | +----+ |  |
373   . |                          |  | |kind| |  |
374   . |                          |  | +----+ |  |
375   . |        :            :    |  | |stat| |  |    :            :
376   . |        :  DIFF pro0 :    |  | +----+ |  |    :  DIFF pro2 :
377   . |        :  SAME con1 :    |  |        |  |    :  SAME con1 :
378   . |        :            :    |  +--------+  |    :            :
379   . |        :            :    |              |    :            :
380   . |        : back       :    |  back        |    : back       :
381   . v        : +--------+ :    |  +--------+  |    : +--------+ :
382   back_deps  : |dep_link| :    |  |dep_link|  |    : |dep_link| :
383   +-----+    : | +----+ | :    |  | +----+ |  |    : | +----+ | :
384   |first|----->| |next|-+------+->| |next|-+--+----->| |next|-+--->NULL
385   +-----+    : | +----+ | :    |  | +----+ |  |    : | +----+ | :
386   .    ^     : |     ^  | :    |  |     ^  |  |    : |        | :
387   .    |     : |     |  | :    |  |     |  |  |    : |        | :
388   .    +--<----+--+  +--+---<--+--+--+  +--+--+--<---+--+     | :
389   .          : |  |     | :    |  |  |     |  |    : |  |     | :
390   .          : | +----+ | :    |  | +----+ |  |    : | +----+ | :
391   .          : | |prev| | :    |  | |prev| |  |    : | |prev| | :
392   .          : | |next| | :    |  | |next| |  |    : | |next| | :
393   .          : | +----+ | :    |  | +----+ |  |    : | +----+ | :
394   .          : |        | :<-+ |  |        |  |<-+ : |        | :<-+
395   .          : | +----+ | :  | |  | +----+ |  |  | : | +----+ | :  |
396   .          : | |node|-+----+ |  | |node|-+--+--+ : | |node|-+----+
397   .          : | +----+ | :    |  | +----+ |  |    : | +----+ | :
398   .          : |        | :    |  |        |  |    : |        | :
399   .          : +--------+ :    |  +--------+  |    : +--------+ :
400   .          :            :    |              |    :            :
401   .          : dep_node A :    |  dep_node Y  |    : dep_node B :
402   .          +------------+    +--------------+    +------------+
403*/
404
405struct _dep_node
406{
407  /* Backward link.  */
408  struct _dep_link back;
409
410  /* The dep.  */
411  struct _dep dep;
412
413  /* Forward link.  */
414  struct _dep_link forw;
415};
416
417#define DEP_NODE_BACK(N) (&(N)->back)
418#define DEP_NODE_DEP(N) (&(N)->dep)
419#define DEP_NODE_FORW(N) (&(N)->forw)
420
421/* The following enumeration values tell us what dependencies we
422   should use to implement the barrier.  We use true-dependencies for
423   TRUE_BARRIER and anti-dependencies for MOVE_BARRIER.  */
424enum reg_pending_barrier_mode
425{
426  NOT_A_BARRIER = 0,
427  MOVE_BARRIER,
428  TRUE_BARRIER
429};
430
431/* Whether a register movement is associated with a call.  */
432enum post_call_group
433{
434  not_post_call,
435  post_call,
436  post_call_initial
437};
438
439/* Insns which affect pseudo-registers.  */
440struct deps_reg
441{
442  rtx uses;
443  rtx sets;
444  rtx implicit_sets;
445  rtx clobbers;
446  int uses_length;
447  int clobbers_length;
448};
449
450/* Describe state of dependencies used during sched_analyze phase.  */
451struct deps_desc
452{
453  /* The *_insns and *_mems are paired lists.  Each pending memory operation
454     will have a pointer to the MEM rtx on one list and a pointer to the
455     containing insn on the other list in the same place in the list.  */
456
457  /* We can't use add_dependence like the old code did, because a single insn
458     may have multiple memory accesses, and hence needs to be on the list
459     once for each memory access.  Add_dependence won't let you add an insn
460     to a list more than once.  */
461
462  /* An INSN_LIST containing all insns with pending read operations.  */
463  rtx pending_read_insns;
464
465  /* An EXPR_LIST containing all MEM rtx's which are pending reads.  */
466  rtx pending_read_mems;
467
468  /* An INSN_LIST containing all insns with pending write operations.  */
469  rtx pending_write_insns;
470
471  /* An EXPR_LIST containing all MEM rtx's which are pending writes.  */
472  rtx pending_write_mems;
473
474  /* We must prevent the above lists from ever growing too large since
475     the number of dependencies produced is at least O(N*N),
476     and execution time is at least O(4*N*N), as a function of the
477     length of these pending lists.  */
478
479  /* Indicates the length of the pending_read list.  */
480  int pending_read_list_length;
481
482  /* Indicates the length of the pending_write list.  */
483  int pending_write_list_length;
484
485  /* Length of the pending memory flush list. Large functions with no
486     calls may build up extremely large lists.  */
487  int pending_flush_length;
488
489  /* The last insn upon which all memory references must depend.
490     This is an insn which flushed the pending lists, creating a dependency
491     between it and all previously pending memory references.  This creates
492     a barrier (or a checkpoint) which no memory reference is allowed to cross.
493
494     This includes all non constant CALL_INSNs.  When we do interprocedural
495     alias analysis, this restriction can be relaxed.
496     This may also be an INSN that writes memory if the pending lists grow
497     too large.  */
498  rtx last_pending_memory_flush;
499
500  /* A list of the last function calls we have seen.  We use a list to
501     represent last function calls from multiple predecessor blocks.
502     Used to prevent register lifetimes from expanding unnecessarily.  */
503  rtx last_function_call;
504
505  /* A list of the last function calls that may not return normally
506     we have seen.  We use a list to represent last function calls from
507     multiple predecessor blocks.  Used to prevent moving trapping insns
508     across such calls.  */
509  rtx last_function_call_may_noreturn;
510
511  /* A list of insns which use a pseudo register that does not already
512     cross a call.  We create dependencies between each of those insn
513     and the next call insn, to ensure that they won't cross a call after
514     scheduling is done.  */
515  rtx sched_before_next_call;
516
517  /* Used to keep post-call pseudo/hard reg movements together with
518     the call.  */
519  enum post_call_group in_post_call_group_p;
520
521  /* The last debug insn we've seen.  */
522  rtx last_debug_insn;
523
524  /* The maximum register number for the following arrays.  Before reload
525     this is max_reg_num; after reload it is FIRST_PSEUDO_REGISTER.  */
526  int max_reg;
527
528  /* Element N is the next insn that sets (hard or pseudo) register
529     N within the current basic block; or zero, if there is no
530     such insn.  Needed for new registers which may be introduced
531     by splitting insns.  */
532  struct deps_reg *reg_last;
533
534  /* Element N is set for each register that has any nonzero element
535     in reg_last[N].{uses,sets,clobbers}.  */
536  regset_head reg_last_in_use;
537
538  /* Element N is set for each register that is conditionally set.  */
539  regset_head reg_conditional_sets;
540
541  /* Shows the last value of reg_pending_barrier associated with the insn.  */
542  enum reg_pending_barrier_mode last_reg_pending_barrier;
543
544  /* True when this context should be treated as a readonly by
545     the analysis.  */
546  BOOL_BITFIELD readonly : 1;
547};
548
549typedef struct deps_desc *deps_t;
550
551/* This structure holds some state of the current scheduling pass, and
552   contains some function pointers that abstract out some of the non-generic
553   functionality from functions such as schedule_block or schedule_insn.
554   There is one global variable, current_sched_info, which points to the
555   sched_info structure currently in use.  */
556struct haifa_sched_info
557{
558  /* Add all insns that are initially ready to the ready list.  Called once
559     before scheduling a set of insns.  */
560  void (*init_ready_list) (void);
561  /* Called after taking an insn from the ready list.  Returns nonzero if
562     this insn can be scheduled, nonzero if we should silently discard it.  */
563  int (*can_schedule_ready_p) (rtx);
564  /* Return nonzero if there are more insns that should be scheduled.  */
565  int (*schedule_more_p) (void);
566  /* Called after an insn has all its hard dependencies resolved.
567     Adjusts status of instruction (which is passed through second parameter)
568     to indicate if instruction should be moved to the ready list or the
569     queue, or if it should silently discard it (until next resolved
570     dependence).  */
571  ds_t (*new_ready) (rtx, ds_t);
572  /* Compare priority of two insns.  Return a positive number if the second
573     insn is to be preferred for scheduling, and a negative one if the first
574     is to be preferred.  Zero if they are equally good.  */
575  int (*rank) (rtx, rtx);
576  /* Return a string that contains the insn uid and optionally anything else
577     necessary to identify this insn in an output.  It's valid to use a
578     static buffer for this.  The ALIGNED parameter should cause the string
579     to be formatted so that multiple output lines will line up nicely.  */
580  const char *(*print_insn) (const_rtx, int);
581  /* Return nonzero if an insn should be included in priority
582     calculations.  */
583  int (*contributes_to_priority) (rtx, rtx);
584
585  /* Return true if scheduling insn (passed as the parameter) will trigger
586     finish of scheduling current block.  */
587  bool (*insn_finishes_block_p) (rtx);
588
589  /* The boundaries of the set of insns to be scheduled.  */
590  rtx prev_head, next_tail;
591
592  /* Filled in after the schedule is finished; the first and last scheduled
593     insns.  */
594  rtx head, tail;
595
596  /* If nonzero, enables an additional sanity check in schedule_block.  */
597  unsigned int queue_must_finish_empty:1;
598
599  /* Maximum priority that has been assigned to an insn.  */
600  int sched_max_insns_priority;
601
602  /* Hooks to support speculative scheduling.  */
603
604  /* Called to notify frontend that instruction is being added (second
605     parameter == 0) or removed (second parameter == 1).  */
606  void (*add_remove_insn) (rtx, int);
607
608  /* Called to notify frontend that instruction is being scheduled.
609     The first parameter - instruction to scheduled, the second parameter -
610     last scheduled instruction.  */
611  void (*begin_schedule_ready) (rtx, rtx);
612
613  /* If the second parameter is not NULL, return nonnull value, if the
614     basic block should be advanced.
615     If the second parameter is NULL, return the next basic block in EBB.
616     The first parameter is the current basic block in EBB.  */
617  basic_block (*advance_target_bb) (basic_block, rtx);
618
619  /* ??? FIXME: should use straight bitfields inside sched_info instead of
620     this flag field.  */
621  unsigned int flags;
622};
623
624/* This structure holds description of the properties for speculative
625   scheduling.  */
626struct spec_info_def
627{
628  /* Holds types of allowed speculations: BEGIN_{DATA|CONTROL},
629     BE_IN_{DATA_CONTROL}.  */
630  int mask;
631
632  /* A dump file for additional information on speculative scheduling.  */
633  FILE *dump;
634
635  /* Minimal cumulative weakness of speculative instruction's
636     dependencies, so that insn will be scheduled.  */
637  dw_t data_weakness_cutoff;
638
639  /* Minimal usefulness of speculative instruction to be considered for
640     scheduling.  */
641  int control_weakness_cutoff;
642
643  /* Flags from the enum SPEC_SCHED_FLAGS.  */
644  int flags;
645};
646typedef struct spec_info_def *spec_info_t;
647
648extern spec_info_t spec_info;
649
650extern struct haifa_sched_info *current_sched_info;
651
652/* Do register pressure sensitive insn scheduling if the flag is set
653   up.  */
654extern bool sched_pressure_p;
655
656/* Map regno -> its cover class.  The map defined only when
657   SCHED_PRESSURE_P is true.  */
658extern enum reg_class *sched_regno_cover_class;
659
660/* Indexed by INSN_UID, the collection of all data associated with
661   a single instruction.  */
662
663struct _haifa_deps_insn_data
664{
665  /* The number of incoming edges in the forward dependency graph.
666     As scheduling proceeds, counts are decreased.  An insn moves to
667     the ready queue when its counter reaches zero.  */
668  int dep_count;
669
670  /* Nonzero if instruction has internal dependence
671     (e.g. add_dependence was invoked with (insn == elem)).  */
672  unsigned int has_internal_dep;
673
674  /* NB: We can't place 'struct _deps_list' here instead of deps_list_t into
675     h_i_d because when h_i_d extends, addresses of the deps_list->first
676     change without updating deps_list->first->next->prev_nextp.  Thus
677     BACK_DEPS and RESOLVED_BACK_DEPS are allocated on the heap and FORW_DEPS
678     list is allocated on the obstack.  */
679
680  /* A list of hard backward dependencies.  The insn is a consumer of all the
681     deps mentioned here.  */
682  deps_list_t hard_back_deps;
683
684  /* A list of speculative (weak) dependencies.  The insn is a consumer of all
685     the deps mentioned here.  */
686  deps_list_t spec_back_deps;
687
688  /* A list of insns which depend on the instruction.  Unlike 'back_deps',
689     it represents forward dependencies.  */
690  deps_list_t forw_deps;
691
692  /* A list of scheduled producers of the instruction.  Links are being moved
693     from 'back_deps' to 'resolved_back_deps' while scheduling.  */
694  deps_list_t resolved_back_deps;
695
696  /* A list of scheduled consumers of the instruction.  Links are being moved
697     from 'forw_deps' to 'resolved_forw_deps' while scheduling to fasten the
698     search in 'forw_deps'.  */
699  deps_list_t resolved_forw_deps;
700
701  /* Some insns (e.g. call) are not allowed to move across blocks.  */
702  unsigned int cant_move : 1;
703};
704
705/* Bits used for storing values of the fields in the following
706   structure.  */
707#define INCREASE_BITS 8
708
709/* The structure describes how the corresponding insn increases the
710   register pressure for each cover class.  */
711struct reg_pressure_data
712{
713  /* Pressure increase for given class because of clobber.  */
714  unsigned int clobber_increase : INCREASE_BITS;
715  /* Increase in register pressure for given class because of register
716     sets. */
717  unsigned int set_increase : INCREASE_BITS;
718  /* Pressure increase for given class because of unused register
719     set.  */
720  unsigned int unused_set_increase : INCREASE_BITS;
721  /* Pressure change: #sets - #deaths.  */
722  int change : INCREASE_BITS;
723};
724
725/* The following structure describes usage of registers by insns.  */
726struct reg_use_data
727{
728  /* Regno used in the insn.  */
729  int regno;
730  /* Insn using the regno.  */
731  rtx insn;
732  /* Cyclic list of elements with the same regno.  */
733  struct reg_use_data *next_regno_use;
734  /* List of elements with the same insn.  */
735  struct reg_use_data *next_insn_use;
736};
737
738/* The following structure describes used sets of registers by insns.
739   Registers are pseudos whose cover class is not NO_REGS or hard
740   registers available for allocations.  */
741struct reg_set_data
742{
743  /* Regno used in the insn.  */
744  int regno;
745  /* Insn setting the regno.  */
746  rtx insn;
747  /* List of elements with the same insn.  */
748  struct reg_set_data *next_insn_set;
749};
750
751struct _haifa_insn_data
752{
753  /* We can't place 'struct _deps_list' into h_i_d instead of deps_list_t
754     because when h_i_d extends, addresses of the deps_list->first
755     change without updating deps_list->first->next->prev_nextp.  */
756
757  /* Logical uid gives the original ordering of the insns.  */
758  int luid;
759
760  /* A priority for each insn.  */
761  int priority;
762
763  /* The minimum clock tick at which the insn becomes ready.  This is
764     used to note timing constraints for the insns in the pending list.  */
765  int tick;
766
767  /* INTER_TICK is used to adjust INSN_TICKs of instructions from the
768     subsequent blocks in a region.  */
769  int inter_tick;
770
771  /* See comment on QUEUE_INDEX macro in haifa-sched.c.  */
772  int queue_index;
773
774  short cost;
775
776  /* Set if there's DEF-USE dependence between some speculatively
777     moved load insn and this one.  */
778  unsigned int fed_by_spec_load : 1;
779  unsigned int is_load_insn : 1;
780
781  /* '> 0' if priority is valid,
782     '== 0' if priority was not yet computed,
783     '< 0' if priority in invalid and should be recomputed.  */
784  signed char priority_status;
785
786  /* What speculations are necessary to apply to schedule the instruction.  */
787  ds_t todo_spec;
788
789  /* What speculations were already applied.  */
790  ds_t done_spec;
791
792  /* What speculations are checked by this instruction.  */
793  ds_t check_spec;
794
795  /* Recovery block for speculation checks.  */
796  basic_block recovery_block;
797
798  /* Original pattern of the instruction.  */
799  rtx orig_pat;
800
801  /* The following array contains info how the insn increases register
802     pressure.  There is an element for each cover class of pseudos
803     referenced in insns.  */
804  struct reg_pressure_data *reg_pressure;
805  /* The following array contains maximal reg pressure between last
806     scheduled insn and given insn.  There is an element for each
807     cover class of pseudos referenced in insns.  This info updated
808     after scheduling each insn for each insn between the two
809     mentioned insns.  */
810  int *max_reg_pressure;
811  /* The following list contains info about used pseudos and hard
812     registers available for allocation.  */
813  struct reg_use_data *reg_use_list;
814  /* The following list contains info about set pseudos and hard
815     registers available for allocation.  */
816  struct reg_set_data *reg_set_list;
817  /* Info about how scheduling the insn changes cost of register
818     pressure excess (between source and target).  */
819  int reg_pressure_excess_cost_change;
820};
821
822typedef struct _haifa_insn_data haifa_insn_data_def;
823typedef haifa_insn_data_def *haifa_insn_data_t;
824
825DEF_VEC_O (haifa_insn_data_def);
826DEF_VEC_ALLOC_O (haifa_insn_data_def, heap);
827
828extern VEC(haifa_insn_data_def, heap) *h_i_d;
829
830#define HID(INSN) (VEC_index (haifa_insn_data_def, h_i_d, INSN_UID (INSN)))
831
832/* Accessor macros for h_i_d.  There are more in haifa-sched.c and
833   sched-rgn.c.  */
834#define INSN_PRIORITY(INSN) (HID (INSN)->priority)
835#define INSN_REG_PRESSURE(INSN) (HID (INSN)->reg_pressure)
836#define INSN_MAX_REG_PRESSURE(INSN) (HID (INSN)->max_reg_pressure)
837#define INSN_REG_USE_LIST(INSN) (HID (INSN)->reg_use_list)
838#define INSN_REG_SET_LIST(INSN) (HID (INSN)->reg_set_list)
839#define INSN_REG_PRESSURE_EXCESS_COST_CHANGE(INSN) \
840  (HID (INSN)->reg_pressure_excess_cost_change)
841#define INSN_PRIORITY_STATUS(INSN) (HID (INSN)->priority_status)
842
843typedef struct _haifa_deps_insn_data haifa_deps_insn_data_def;
844typedef haifa_deps_insn_data_def *haifa_deps_insn_data_t;
845
846DEF_VEC_O (haifa_deps_insn_data_def);
847DEF_VEC_ALLOC_O (haifa_deps_insn_data_def, heap);
848
849extern VEC(haifa_deps_insn_data_def, heap) *h_d_i_d;
850
851#define HDID(INSN) (VEC_index (haifa_deps_insn_data_def, h_d_i_d,	\
852			       INSN_LUID (INSN)))
853#define INSN_DEP_COUNT(INSN)	(HDID (INSN)->dep_count)
854#define HAS_INTERNAL_DEP(INSN)  (HDID (INSN)->has_internal_dep)
855#define INSN_FORW_DEPS(INSN) (HDID (INSN)->forw_deps)
856#define INSN_RESOLVED_BACK_DEPS(INSN) (HDID (INSN)->resolved_back_deps)
857#define INSN_RESOLVED_FORW_DEPS(INSN) (HDID (INSN)->resolved_forw_deps)
858#define INSN_HARD_BACK_DEPS(INSN) (HDID (INSN)->hard_back_deps)
859#define INSN_SPEC_BACK_DEPS(INSN) (HDID (INSN)->spec_back_deps)
860#define CANT_MOVE(INSN)	(HDID (INSN)->cant_move)
861#define CANT_MOVE_BY_LUID(LUID)	(VEC_index (haifa_deps_insn_data_def, h_d_i_d, \
862                                            LUID)->cant_move)
863
864
865#define INSN_PRIORITY(INSN)	(HID (INSN)->priority)
866#define INSN_PRIORITY_STATUS(INSN) (HID (INSN)->priority_status)
867#define INSN_PRIORITY_KNOWN(INSN) (INSN_PRIORITY_STATUS (INSN) > 0)
868#define TODO_SPEC(INSN) (HID (INSN)->todo_spec)
869#define DONE_SPEC(INSN) (HID (INSN)->done_spec)
870#define CHECK_SPEC(INSN) (HID (INSN)->check_spec)
871#define RECOVERY_BLOCK(INSN) (HID (INSN)->recovery_block)
872#define ORIG_PAT(INSN) (HID (INSN)->orig_pat)
873
874/* INSN is either a simple or a branchy speculation check.  */
875#define IS_SPECULATION_CHECK_P(INSN) \
876  (sel_sched_p () ? sel_insn_is_speculation_check (INSN) : RECOVERY_BLOCK (INSN) != NULL)
877
878/* INSN is a speculation check that will simply reexecute the speculatively
879   scheduled instruction if the speculation fails.  */
880#define IS_SPECULATION_SIMPLE_CHECK_P(INSN) \
881  (RECOVERY_BLOCK (INSN) == EXIT_BLOCK_PTR)
882
883/* INSN is a speculation check that will branch to RECOVERY_BLOCK if the
884   speculation fails.  Insns in that block will reexecute the speculatively
885   scheduled code and then will return immediately after INSN thus preserving
886   semantics of the program.  */
887#define IS_SPECULATION_BRANCHY_CHECK_P(INSN) \
888  (RECOVERY_BLOCK (INSN) != NULL && RECOVERY_BLOCK (INSN) != EXIT_BLOCK_PTR)
889
890/* The unchanging bit tracks whether a debug insn is to be handled
891   like an insn (i.e., schedule it) or like a note (e.g., it is next
892   to a basic block boundary.  */
893#define DEBUG_INSN_SCHED_P(insn) \
894  (RTL_FLAG_CHECK1("DEBUG_INSN_SCHED_P", (insn), DEBUG_INSN)->unchanging)
895
896/* True if INSN is a debug insn that is next to a basic block
897   boundary, i.e., it is to be handled by the scheduler like a
898   note.  */
899#define BOUNDARY_DEBUG_INSN_P(insn) \
900  (DEBUG_INSN_P (insn) && !DEBUG_INSN_SCHED_P (insn))
901/* True if INSN is a debug insn that is not next to a basic block
902   boundary, i.e., it is to be handled by the scheduler like an
903   insn.  */
904#define SCHEDULE_DEBUG_INSN_P(insn) \
905  (DEBUG_INSN_P (insn) && DEBUG_INSN_SCHED_P (insn))
906
907/* Dep status (aka ds_t) of the link encapsulates information, that is needed
908   for speculative scheduling.  Namely, it is 4 integers in the range
909   [0, MAX_DEP_WEAK] and 3 bits.
910   The integers correspond to the probability of the dependence to *not*
911   exist, it is the probability, that overcoming of this dependence will
912   not be followed by execution of the recovery code.  Nevertheless,
913   whatever high the probability of success is, recovery code should still
914   be generated to preserve semantics of the program.  To find a way to
915   get/set these integers, please refer to the {get, set}_dep_weak ()
916   functions in sched-deps.c .
917   The 3 bits in the DEP_STATUS correspond to 3 dependence types: true-,
918   output- and anti- dependence.  It is not enough for speculative scheduling
919   to know just the major type of all the dependence between two instructions,
920   as only true dependence can be overcome.
921   There also is the 4-th bit in the DEP_STATUS (HARD_DEP), that is reserved
922   for using to describe instruction's status.  It is set whenever instruction
923   has at least one dependence, that cannot be overcame.
924   See also: check_dep_status () in sched-deps.c .  */
925
926/* We exclude sign bit.  */
927#define BITS_PER_DEP_STATUS (HOST_BITS_PER_INT - 1)
928
929/* First '4' stands for 3 dep type bits and HARD_DEP bit.
930   Second '4' stands for BEGIN_{DATA, CONTROL}, BE_IN_{DATA, CONTROL}
931   dep weakness.  */
932#define BITS_PER_DEP_WEAK ((BITS_PER_DEP_STATUS - 4) / 4)
933
934/* Mask of speculative weakness in dep_status.  */
935#define DEP_WEAK_MASK ((1 << BITS_PER_DEP_WEAK) - 1)
936
937/* This constant means that dependence is fake with 99.999...% probability.
938   This is the maximum value, that can appear in dep_status.
939   Note, that we don't want MAX_DEP_WEAK to be the same as DEP_WEAK_MASK for
940   debugging reasons.  Though, it can be set to DEP_WEAK_MASK, and, when
941   done so, we'll get fast (mul for)/(div by) NO_DEP_WEAK.  */
942#define MAX_DEP_WEAK (DEP_WEAK_MASK - 1)
943
944/* This constant means that dependence is 99.999...% real and it is a really
945   bad idea to overcome it (though this can be done, preserving program
946   semantics).  */
947#define MIN_DEP_WEAK 1
948
949/* This constant represents 100% probability.
950   E.g. it is used to represent weakness of dependence, that doesn't exist.  */
951#define NO_DEP_WEAK (MAX_DEP_WEAK + MIN_DEP_WEAK)
952
953/* Default weakness of speculative dependence.  Used when we can't say
954   neither bad nor good about the dependence.  */
955#define UNCERTAIN_DEP_WEAK (MAX_DEP_WEAK - MAX_DEP_WEAK / 4)
956
957/* Offset for speculative weaknesses in dep_status.  */
958enum SPEC_TYPES_OFFSETS {
959  BEGIN_DATA_BITS_OFFSET = 0,
960  BE_IN_DATA_BITS_OFFSET = BEGIN_DATA_BITS_OFFSET + BITS_PER_DEP_WEAK,
961  BEGIN_CONTROL_BITS_OFFSET = BE_IN_DATA_BITS_OFFSET + BITS_PER_DEP_WEAK,
962  BE_IN_CONTROL_BITS_OFFSET = BEGIN_CONTROL_BITS_OFFSET + BITS_PER_DEP_WEAK
963};
964
965/* The following defines provide numerous constants used to distinguish between
966   different types of speculative dependencies.  */
967
968/* Dependence can be overcome with generation of new data speculative
969   instruction.  */
970#define BEGIN_DATA (((ds_t) DEP_WEAK_MASK) << BEGIN_DATA_BITS_OFFSET)
971
972/* This dependence is to the instruction in the recovery block, that was
973   formed to recover after data-speculation failure.
974   Thus, this dependence can overcome with generating of the copy of
975   this instruction in the recovery block.  */
976#define BE_IN_DATA (((ds_t) DEP_WEAK_MASK) << BE_IN_DATA_BITS_OFFSET)
977
978/* Dependence can be overcome with generation of new control speculative
979   instruction.  */
980#define BEGIN_CONTROL (((ds_t) DEP_WEAK_MASK) << BEGIN_CONTROL_BITS_OFFSET)
981
982/* This dependence is to the instruction in the recovery block, that was
983   formed to recover after control-speculation failure.
984   Thus, this dependence can be overcome with generating of the copy of
985   this instruction in the recovery block.  */
986#define BE_IN_CONTROL (((ds_t) DEP_WEAK_MASK) << BE_IN_CONTROL_BITS_OFFSET)
987
988/* A few convenient combinations.  */
989#define BEGIN_SPEC (BEGIN_DATA | BEGIN_CONTROL)
990#define DATA_SPEC (BEGIN_DATA | BE_IN_DATA)
991#define CONTROL_SPEC (BEGIN_CONTROL | BE_IN_CONTROL)
992#define SPECULATIVE (DATA_SPEC | CONTROL_SPEC)
993#define BE_IN_SPEC (BE_IN_DATA | BE_IN_CONTROL)
994
995/* Constants, that are helpful in iterating through dep_status.  */
996#define FIRST_SPEC_TYPE BEGIN_DATA
997#define LAST_SPEC_TYPE BE_IN_CONTROL
998#define SPEC_TYPE_SHIFT BITS_PER_DEP_WEAK
999
1000/* Dependence on instruction can be of multiple types
1001   (e.g. true and output). This fields enhance REG_NOTE_KIND information
1002   of the dependence.  */
1003#define DEP_TRUE (((ds_t) 1) << (BE_IN_CONTROL_BITS_OFFSET + BITS_PER_DEP_WEAK))
1004#define DEP_OUTPUT (DEP_TRUE << 1)
1005#define DEP_ANTI (DEP_OUTPUT << 1)
1006
1007#define DEP_TYPES (DEP_TRUE | DEP_OUTPUT | DEP_ANTI)
1008
1009/* Instruction has non-speculative dependence.  This bit represents the
1010   property of an instruction - not the one of a dependence.
1011   Therefore, it can appear only in TODO_SPEC field of an instruction.  */
1012#define HARD_DEP (DEP_ANTI << 1)
1013
1014/* This represents the results of calling sched-deps.c functions,
1015   which modify dependencies.  */
1016enum DEPS_ADJUST_RESULT {
1017  /* No dependence needed (e.g. producer == consumer).  */
1018  DEP_NODEP,
1019  /* Dependence is already present and wasn't modified.  */
1020  DEP_PRESENT,
1021  /* Existing dependence was modified to include additional information.  */
1022  DEP_CHANGED,
1023  /* New dependence has been created.  */
1024  DEP_CREATED
1025};
1026
1027/* Represents the bits that can be set in the flags field of the
1028   sched_info structure.  */
1029enum SCHED_FLAGS {
1030  /* If set, generate links between instruction as DEPS_LIST.
1031     Otherwise, generate usual INSN_LIST links.  */
1032  USE_DEPS_LIST = 1,
1033  /* Perform data or control (or both) speculation.
1034     Results in generation of data and control speculative dependencies.
1035     Requires USE_DEPS_LIST set.  */
1036  DO_SPECULATION = USE_DEPS_LIST << 1,
1037  SCHED_RGN = DO_SPECULATION << 1,
1038  SCHED_EBB = SCHED_RGN << 1,
1039  /* Scheduler can possibly create new basic blocks.  Used for assertions.  */
1040  NEW_BBS = SCHED_EBB << 1,
1041  SEL_SCHED = NEW_BBS << 1
1042};
1043
1044enum SPEC_SCHED_FLAGS {
1045  COUNT_SPEC_IN_CRITICAL_PATH = 1,
1046  PREFER_NON_DATA_SPEC = COUNT_SPEC_IN_CRITICAL_PATH << 1,
1047  PREFER_NON_CONTROL_SPEC = PREFER_NON_DATA_SPEC << 1,
1048  SEL_SCHED_SPEC_DONT_CHECK_CONTROL = PREFER_NON_CONTROL_SPEC << 1
1049};
1050
1051#define NOTE_NOT_BB_P(NOTE) (NOTE_P (NOTE) && (NOTE_KIND (NOTE)	\
1052					       != NOTE_INSN_BASIC_BLOCK))
1053
1054extern FILE *sched_dump;
1055extern int sched_verbose;
1056
1057extern spec_info_t spec_info;
1058extern bool haifa_recovery_bb_ever_added_p;
1059
1060/* Exception Free Loads:
1061
1062   We define five classes of speculative loads: IFREE, IRISKY,
1063   PFREE, PRISKY, and MFREE.
1064
1065   IFREE loads are loads that are proved to be exception-free, just
1066   by examining the load insn.  Examples for such loads are loads
1067   from TOC and loads of global data.
1068
1069   IRISKY loads are loads that are proved to be exception-risky,
1070   just by examining the load insn.  Examples for such loads are
1071   volatile loads and loads from shared memory.
1072
1073   PFREE loads are loads for which we can prove, by examining other
1074   insns, that they are exception-free.  Currently, this class consists
1075   of loads for which we are able to find a "similar load", either in
1076   the target block, or, if only one split-block exists, in that split
1077   block.  Load2 is similar to load1 if both have same single base
1078   register.  We identify only part of the similar loads, by finding
1079   an insn upon which both load1 and load2 have a DEF-USE dependence.
1080
1081   PRISKY loads are loads for which we can prove, by examining other
1082   insns, that they are exception-risky.  Currently we have two proofs for
1083   such loads.  The first proof detects loads that are probably guarded by a
1084   test on the memory address.  This proof is based on the
1085   backward and forward data dependence information for the region.
1086   Let load-insn be the examined load.
1087   Load-insn is PRISKY iff ALL the following hold:
1088
1089   - insn1 is not in the same block as load-insn
1090   - there is a DEF-USE dependence chain (insn1, ..., load-insn)
1091   - test-insn is either a compare or a branch, not in the same block
1092     as load-insn
1093   - load-insn is reachable from test-insn
1094   - there is a DEF-USE dependence chain (insn1, ..., test-insn)
1095
1096   This proof might fail when the compare and the load are fed
1097   by an insn not in the region.  To solve this, we will add to this
1098   group all loads that have no input DEF-USE dependence.
1099
1100   The second proof detects loads that are directly or indirectly
1101   fed by a speculative load.  This proof is affected by the
1102   scheduling process.  We will use the flag  fed_by_spec_load.
1103   Initially, all insns have this flag reset.  After a speculative
1104   motion of an insn, if insn is either a load, or marked as
1105   fed_by_spec_load, we will also mark as fed_by_spec_load every
1106   insn1 for which a DEF-USE dependence (insn, insn1) exists.  A
1107   load which is fed_by_spec_load is also PRISKY.
1108
1109   MFREE (maybe-free) loads are all the remaining loads. They may be
1110   exception-free, but we cannot prove it.
1111
1112   Now, all loads in IFREE and PFREE classes are considered
1113   exception-free, while all loads in IRISKY and PRISKY classes are
1114   considered exception-risky.  As for loads in the MFREE class,
1115   these are considered either exception-free or exception-risky,
1116   depending on whether we are pessimistic or optimistic.  We have
1117   to take the pessimistic approach to assure the safety of
1118   speculative scheduling, but we can take the optimistic approach
1119   by invoking the -fsched_spec_load_dangerous option.  */
1120
1121enum INSN_TRAP_CLASS
1122{
1123  TRAP_FREE = 0, IFREE = 1, PFREE_CANDIDATE = 2,
1124  PRISKY_CANDIDATE = 3, IRISKY = 4, TRAP_RISKY = 5
1125};
1126
1127#define WORST_CLASS(class1, class2) \
1128((class1 > class2) ? class1 : class2)
1129
1130#ifndef __GNUC__
1131#define __inline
1132#endif
1133
1134#ifndef HAIFA_INLINE
1135#define HAIFA_INLINE __inline
1136#endif
1137
1138struct sched_deps_info_def
1139{
1140  /* Called when computing dependencies for a JUMP_INSN.  This function
1141     should store the set of registers that must be considered as set by
1142     the jump in the regset.  */
1143  void (*compute_jump_reg_dependencies) (rtx, regset, regset, regset);
1144
1145  /* Start analyzing insn.  */
1146  void (*start_insn) (rtx);
1147
1148  /* Finish analyzing insn.  */
1149  void (*finish_insn) (void);
1150
1151  /* Start analyzing insn LHS (Left Hand Side).  */
1152  void (*start_lhs) (rtx);
1153
1154  /* Finish analyzing insn LHS.  */
1155  void (*finish_lhs) (void);
1156
1157  /* Start analyzing insn RHS (Right Hand Side).  */
1158  void (*start_rhs) (rtx);
1159
1160  /* Finish analyzing insn RHS.  */
1161  void (*finish_rhs) (void);
1162
1163  /* Note set of the register.  */
1164  void (*note_reg_set) (int);
1165
1166  /* Note clobber of the register.  */
1167  void (*note_reg_clobber) (int);
1168
1169  /* Note use of the register.  */
1170  void (*note_reg_use) (int);
1171
1172  /* Note memory dependence of type DS between MEM1 and MEM2 (which is
1173     in the INSN2).  */
1174  void (*note_mem_dep) (rtx mem1, rtx mem2, rtx insn2, ds_t ds);
1175
1176  /* Note a dependence of type DS from the INSN.  */
1177  void (*note_dep) (rtx insn, ds_t ds);
1178
1179  /* Nonzero if we should use cselib for better alias analysis.  This
1180     must be 0 if the dependency information is used after sched_analyze
1181     has completed, e.g. if we're using it to initialize state for successor
1182     blocks in region scheduling.  */
1183  unsigned int use_cselib : 1;
1184
1185  /* If set, generate links between instruction as DEPS_LIST.
1186     Otherwise, generate usual INSN_LIST links.  */
1187  unsigned int use_deps_list : 1;
1188
1189  /* Generate data and control speculative dependencies.
1190     Requires USE_DEPS_LIST set.  */
1191  unsigned int generate_spec_deps : 1;
1192};
1193
1194extern struct sched_deps_info_def *sched_deps_info;
1195
1196
1197/* Functions in sched-deps.c.  */
1198extern bool sched_insns_conditions_mutex_p (const_rtx, const_rtx);
1199extern bool sched_insn_is_legitimate_for_speculation_p (const_rtx, ds_t);
1200extern void add_dependence (rtx, rtx, enum reg_note);
1201extern void sched_analyze (struct deps_desc *, rtx, rtx);
1202extern void init_deps (struct deps_desc *, bool);
1203extern void init_deps_reg_last (struct deps_desc *);
1204extern void free_deps (struct deps_desc *);
1205extern void init_deps_global (void);
1206extern void finish_deps_global (void);
1207extern void deps_analyze_insn (struct deps_desc *, rtx);
1208extern void remove_from_deps (struct deps_desc *, rtx);
1209
1210extern dw_t get_dep_weak_1 (ds_t, ds_t);
1211extern dw_t get_dep_weak (ds_t, ds_t);
1212extern ds_t set_dep_weak (ds_t, ds_t, dw_t);
1213extern dw_t estimate_dep_weak (rtx, rtx);
1214extern ds_t ds_merge (ds_t, ds_t);
1215extern ds_t ds_full_merge (ds_t, ds_t, rtx, rtx);
1216extern ds_t ds_max_merge (ds_t, ds_t);
1217extern dw_t ds_weak (ds_t);
1218extern ds_t ds_get_speculation_types (ds_t);
1219extern ds_t ds_get_max_dep_weak (ds_t);
1220
1221extern void sched_deps_init (bool);
1222extern void sched_deps_finish (void);
1223
1224extern void haifa_note_reg_set (int);
1225extern void haifa_note_reg_clobber (int);
1226extern void haifa_note_reg_use (int);
1227
1228extern void maybe_extend_reg_info_p (void);
1229
1230extern void deps_start_bb (struct deps_desc *, rtx);
1231extern enum reg_note ds_to_dt (ds_t);
1232
1233extern bool deps_pools_are_empty_p (void);
1234extern void sched_free_deps (rtx, rtx, bool);
1235extern void extend_dependency_caches (int, bool);
1236
1237extern void debug_ds (ds_t);
1238
1239
1240/* Functions in haifa-sched.c.  */
1241extern void sched_init_region_reg_pressure_info (void);
1242extern int haifa_classify_insn (const_rtx);
1243extern void get_ebb_head_tail (basic_block, basic_block, rtx *, rtx *);
1244extern int no_real_insns_p (const_rtx, const_rtx);
1245
1246extern int insn_cost (rtx);
1247extern int dep_cost_1 (dep_t, dw_t);
1248extern int dep_cost (dep_t);
1249extern int set_priorities (rtx, rtx);
1250
1251extern void sched_setup_bb_reg_pressure_info (basic_block, rtx);
1252extern void schedule_block (basic_block *);
1253
1254extern int cycle_issued_insns;
1255extern int issue_rate;
1256extern int dfa_lookahead;
1257
1258extern void ready_sort (struct ready_list *);
1259extern rtx ready_element (struct ready_list *, int);
1260extern rtx *ready_lastpos (struct ready_list *);
1261
1262extern int try_ready (rtx);
1263extern void sched_extend_ready_list (int);
1264extern void sched_finish_ready_list (void);
1265extern void sched_change_pattern (rtx, rtx);
1266extern int sched_speculate_insn (rtx, ds_t, rtx *);
1267extern void unlink_bb_notes (basic_block, basic_block);
1268extern void add_block (basic_block, basic_block);
1269extern rtx bb_note (basic_block);
1270extern void concat_note_lists (rtx, rtx *);
1271extern rtx sched_emit_insn (rtx);
1272
1273
1274/* Types and functions in sched-rgn.c.  */
1275
1276/* A region is the main entity for interblock scheduling: insns
1277   are allowed to move between blocks in the same region, along
1278   control flow graph edges, in the 'up' direction.  */
1279typedef struct
1280{
1281  /* Number of extended basic blocks in region.  */
1282  int rgn_nr_blocks;
1283  /* cblocks in the region (actually index in rgn_bb_table).  */
1284  int rgn_blocks;
1285  /* Dependencies for this region are already computed.  Basically, indicates,
1286     that this is a recovery block.  */
1287  unsigned int dont_calc_deps : 1;
1288  /* This region has at least one non-trivial ebb.  */
1289  unsigned int has_real_ebb : 1;
1290}
1291region;
1292
1293extern int nr_regions;
1294extern region *rgn_table;
1295extern int *rgn_bb_table;
1296extern int *block_to_bb;
1297extern int *containing_rgn;
1298
1299/* Often used short-hand in the scheduler.  The rest of the compiler uses
1300   BLOCK_FOR_INSN(INSN) and an indirect reference to get the basic block
1301   number ("index").  For historical reasons, the scheduler does not.  */
1302#define BLOCK_NUM(INSN)	      (BLOCK_FOR_INSN (INSN)->index + 0)
1303
1304#define RGN_NR_BLOCKS(rgn) (rgn_table[rgn].rgn_nr_blocks)
1305#define RGN_BLOCKS(rgn) (rgn_table[rgn].rgn_blocks)
1306#define RGN_DONT_CALC_DEPS(rgn) (rgn_table[rgn].dont_calc_deps)
1307#define RGN_HAS_REAL_EBB(rgn) (rgn_table[rgn].has_real_ebb)
1308#define BLOCK_TO_BB(block) (block_to_bb[block])
1309#define CONTAINING_RGN(block) (containing_rgn[block])
1310
1311/* The mapping from ebb to block.  */
1312extern int *ebb_head;
1313#define BB_TO_BLOCK(ebb) (rgn_bb_table[ebb_head[ebb]])
1314#define EBB_FIRST_BB(ebb) BASIC_BLOCK (BB_TO_BLOCK (ebb))
1315#define EBB_LAST_BB(ebb) BASIC_BLOCK (rgn_bb_table[ebb_head[ebb + 1] - 1])
1316#define INSN_BB(INSN) (BLOCK_TO_BB (BLOCK_NUM (INSN)))
1317
1318extern int current_nr_blocks;
1319extern int current_blocks;
1320extern int target_bb;
1321
1322extern bool sched_is_disabled_for_current_region_p (void);
1323extern void sched_rgn_init (bool);
1324extern void sched_rgn_finish (void);
1325extern void rgn_setup_region (int);
1326extern void sched_rgn_compute_dependencies (int);
1327extern void sched_rgn_local_init (int);
1328extern void sched_rgn_local_finish (void);
1329extern void sched_rgn_local_free (void);
1330extern void extend_regions (void);
1331extern void rgn_make_new_region_out_of_new_block (basic_block);
1332
1333extern void compute_priorities (void);
1334extern void increase_insn_priority (rtx, int);
1335extern void debug_rgn_dependencies (int);
1336extern void debug_dependencies (rtx, rtx);
1337extern void free_rgn_deps (void);
1338extern int contributes_to_priority (rtx, rtx);
1339extern void extend_rgns (int *, int *, sbitmap, int *);
1340extern void deps_join (struct deps_desc *, struct deps_desc *);
1341
1342extern void rgn_setup_common_sched_info (void);
1343extern void rgn_setup_sched_infos (void);
1344
1345extern void debug_regions (void);
1346extern void debug_region (int);
1347extern void dump_region_dot (FILE *, int);
1348extern void dump_region_dot_file (const char *, int);
1349
1350extern void haifa_sched_init (void);
1351extern void haifa_sched_finish (void);
1352
1353/* sched-deps.c interface to walk, add, search, update, resolve, delete
1354   and debug instruction dependencies.  */
1355
1356/* Constants defining dependences lists.  */
1357
1358/* No list.  */
1359#define SD_LIST_NONE (0)
1360
1361/* hard_back_deps.  */
1362#define SD_LIST_HARD_BACK (1)
1363
1364/* spec_back_deps.  */
1365#define SD_LIST_SPEC_BACK (2)
1366
1367/* forw_deps.  */
1368#define SD_LIST_FORW (4)
1369
1370/* resolved_back_deps.  */
1371#define SD_LIST_RES_BACK (8)
1372
1373/* resolved_forw_deps.  */
1374#define SD_LIST_RES_FORW (16)
1375
1376#define SD_LIST_BACK (SD_LIST_HARD_BACK | SD_LIST_SPEC_BACK)
1377
1378/* A type to hold above flags.  */
1379typedef int sd_list_types_def;
1380
1381extern void sd_next_list (const_rtx, sd_list_types_def *, deps_list_t *, bool *);
1382
1383/* Iterator to walk through, resolve and delete dependencies.  */
1384struct _sd_iterator
1385{
1386  /* What lists to walk.  Can be any combination of SD_LIST_* flags.  */
1387  sd_list_types_def types;
1388
1389  /* Instruction dependencies lists of which will be walked.  */
1390  rtx insn;
1391
1392  /* Pointer to the next field of the previous element.  This is not
1393     simply a pointer to the next element to allow easy deletion from the
1394     list.  When a dep is being removed from the list the iterator
1395     will automatically advance because the value in *linkp will start
1396     referring to the next element.  */
1397  dep_link_t *linkp;
1398
1399  /* True if the current list is a resolved one.  */
1400  bool resolved_p;
1401};
1402
1403typedef struct _sd_iterator sd_iterator_def;
1404
1405/* ??? We can move some definitions that are used in below inline functions
1406   out of sched-int.h to sched-deps.c provided that the below functions will
1407   become global externals.
1408   These definitions include:
1409   * struct _deps_list: opaque pointer is needed at global scope.
1410   * struct _dep_link: opaque pointer is needed at scope of sd_iterator_def.
1411   * struct _dep_node: opaque pointer is needed at scope of
1412   struct _deps_link.  */
1413
1414/* Return initialized iterator.  */
1415static inline sd_iterator_def
1416sd_iterator_start (rtx insn, sd_list_types_def types)
1417{
1418  /* Some dep_link a pointer to which will return NULL.  */
1419  static dep_link_t null_link = NULL;
1420
1421  sd_iterator_def i;
1422
1423  i.types = types;
1424  i.insn = insn;
1425  i.linkp = &null_link;
1426
1427  /* Avoid 'uninitialized warning'.  */
1428  i.resolved_p = false;
1429
1430  return i;
1431}
1432
1433/* Return the current element.  */
1434static inline bool
1435sd_iterator_cond (sd_iterator_def *it_ptr, dep_t *dep_ptr)
1436{
1437  dep_link_t link = *it_ptr->linkp;
1438
1439  if (link != NULL)
1440    {
1441      *dep_ptr = DEP_LINK_DEP (link);
1442      return true;
1443    }
1444  else
1445    {
1446      sd_list_types_def types = it_ptr->types;
1447
1448      if (types != SD_LIST_NONE)
1449	/* Switch to next list.  */
1450	{
1451	  deps_list_t list;
1452
1453	  sd_next_list (it_ptr->insn,
1454			&it_ptr->types, &list, &it_ptr->resolved_p);
1455
1456	  it_ptr->linkp = &DEPS_LIST_FIRST (list);
1457
1458	  if (list)
1459	    return sd_iterator_cond (it_ptr, dep_ptr);
1460	}
1461
1462      *dep_ptr = NULL;
1463      return false;
1464    }
1465}
1466
1467/* Advance iterator.  */
1468static inline void
1469sd_iterator_next (sd_iterator_def *it_ptr)
1470{
1471  it_ptr->linkp = &DEP_LINK_NEXT (*it_ptr->linkp);
1472}
1473
1474/* A cycle wrapper.  */
1475#define FOR_EACH_DEP(INSN, LIST_TYPES, ITER, DEP)		\
1476  for ((ITER) = sd_iterator_start ((INSN), (LIST_TYPES));	\
1477       sd_iterator_cond (&(ITER), &(DEP));			\
1478       sd_iterator_next (&(ITER)))
1479
1480extern int sd_lists_size (const_rtx, sd_list_types_def);
1481extern bool sd_lists_empty_p (const_rtx, sd_list_types_def);
1482extern void sd_init_insn (rtx);
1483extern void sd_finish_insn (rtx);
1484extern dep_t sd_find_dep_between (rtx, rtx, bool);
1485extern void sd_add_dep (dep_t, bool);
1486extern enum DEPS_ADJUST_RESULT sd_add_or_update_dep (dep_t, bool);
1487extern void sd_resolve_dep (sd_iterator_def);
1488extern void sd_copy_back_deps (rtx, rtx, bool);
1489extern void sd_delete_dep (sd_iterator_def);
1490extern void sd_debug_lists (rtx, sd_list_types_def);
1491
1492#endif /* INSN_SCHEDULING */
1493
1494/* Functions in sched-vis.c.  These must be outside INSN_SCHEDULING as
1495   sched-vis.c is compiled always.  */
1496extern void print_insn (char *, const_rtx, int);
1497extern void print_pattern (char *, const_rtx, int);
1498extern void print_value (char *, const_rtx, int);
1499
1500#endif /* GCC_SCHED_INT_H */
1501