1/* Form lists of pseudo register references for autoinc optimization
2   for GNU compiler.  This is part of flow optimization.
3   Copyright (C) 1999, 2000, 2001, 2003, 2004, 2005
4   Free Software Foundation, Inc.
5   Contributed by Michael P. Hayes (m.hayes@elec.canterbury.ac.nz)
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 2, 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 COPYING.  If not, write to the Free
21Software Foundation, 51 Franklin Street, Fifth Floor, Boston, MA
2202110-1301, USA.  */
23
24#ifndef GCC_DF_H
25#define GCC_DF_H
26
27#include "bitmap.h"
28#include "basic-block.h"
29
30#define DF_RD		1	/* Reaching definitions.  */
31#define DF_RU		2	/* Reaching uses.  */
32#define DF_LR		4	/* Live registers.  */
33#define DF_DU_CHAIN	8	/* Def-use chain.  */
34#define DF_UD_CHAIN	16	/* Use-def chain.  */
35#define DF_REG_INFO	32	/* Register info.  */
36#define DF_RD_CHAIN	64	/* Reg-def chain.  */
37#define DF_RU_CHAIN	128	/* Reg-use chain.  */
38#define DF_ALL		255
39#define DF_HARD_REGS	1024	/* Mark hard registers.  */
40#define DF_EQUIV_NOTES	2048	/* Mark uses present in EQUIV/EQUAL notes.  */
41#define DF_SUBREGS	4096	/* Return subregs rather than the inner reg.  */
42
43enum df_ref_type {DF_REF_REG_DEF, DF_REF_REG_USE, DF_REF_REG_MEM_LOAD,
44		  DF_REF_REG_MEM_STORE};
45
46#define DF_REF_TYPE_NAMES {"def", "use", "mem load", "mem store"}
47
48/* Link on a def-use or use-def chain.  */
49struct df_link
50{
51  struct df_link *next;
52  struct ref *ref;
53};
54
55enum df_ref_flags
56  {
57    /* Read-modify-write refs generate both a use and a def and
58       these are marked with this flag to show that they are not
59       independent.  */
60    DF_REF_READ_WRITE = 1,
61
62    /* This flag is set, if we stripped the subreg from the reference.
63       In this case we must make conservative guesses, at what the
64       outer mode was.  */
65    DF_REF_STRIPPED = 2
66  };
67
68
69/* Define a register reference structure.  One of these is allocated
70   for every register reference (use or def).  Note some register
71   references (e.g., post_inc, subreg) generate both a def and a use.  */
72struct ref
73{
74  rtx reg;			/* The register referenced.  */
75  rtx insn;			/* Insn containing ref.  */
76  rtx *loc;			/* The location of the reg.  */
77  struct df_link *chain;	/* Head of def-use or use-def chain.  */
78  unsigned int id;		/* Ref index.  */
79  enum df_ref_type type;	/* Type of ref.  */
80  enum df_ref_flags flags;	/* Various flags.  */
81  void *data;			/* The data assigned to it by user.  */
82};
83
84
85/* One of these structures is allocated for every insn.  */
86struct insn_info
87{
88  struct df_link *defs;		/* Head of insn-def chain.  */
89  struct df_link *uses;		/* Head of insn-use chain.  */
90  /* ???? The following luid field should be considered private so that
91     we can change it on the fly to accommodate new insns?  */
92  int luid;			/* Logical UID.  */
93};
94
95
96/* One of these structures is allocated for every reg.  */
97struct reg_info
98{
99  struct df_link *defs;		/* Head of reg-def chain.  */
100  struct df_link *uses;		/* Head of reg-use chain.  */
101  int lifetime;
102  int n_defs;
103  int n_uses;
104};
105
106
107/* One of these structures is allocated for every basic block.  */
108struct bb_info
109{
110  /* Reaching def bitmaps have def_id elements.  */
111  bitmap rd_kill;
112  bitmap rd_gen;
113  bitmap rd_in;
114  bitmap rd_out;
115  /* Reaching use bitmaps have use_id elements.  */
116  bitmap ru_kill;
117  bitmap ru_gen;
118  bitmap ru_in;
119  bitmap ru_out;
120  /* Live variable bitmaps have n_regs elements.  */
121  bitmap lr_def;
122  bitmap lr_use;
123  bitmap lr_in;
124  bitmap lr_out;
125  int rd_valid;
126  int ru_valid;
127  int lr_valid;
128};
129
130
131struct df
132{
133  int flags;			/* Indicates what's recorded.  */
134  struct bb_info *bbs;		/* Basic block table.  */
135  struct ref **defs;		/* Def table, indexed by def_id.  */
136  struct ref **uses;		/* Use table, indexed by use_id.  */
137  struct ref **reg_def_last;	/* Indexed by regno.  */
138  struct reg_info *regs;	/* Regs table, index by regno.  */
139  unsigned int reg_size;	/* Size of regs table.  */
140  struct insn_info *insns;	/* Insn table, indexed by insn UID.  */
141  unsigned int insn_size;	/* Size of insn table.  */
142  unsigned int def_id;		/* Next def ID.  */
143  unsigned int def_size;	/* Size of def table.  */
144  unsigned int n_defs;		/* Size of def bitmaps.  */
145  unsigned int use_id;		/* Next use ID.  */
146  unsigned int use_size;	/* Size of use table.  */
147  unsigned int n_uses;		/* Size of use bitmaps.  */
148  unsigned int n_bbs;		/* Number of basic blocks.  */
149  unsigned int n_regs;		/* Number of regs.  */
150  unsigned int def_id_save;	/* Saved next def ID.  */
151  unsigned int use_id_save;	/* Saved next use ID.  */
152  bitmap insns_modified;	/* Insns that (may) have changed.  */
153  bitmap bbs_modified;		/* Blocks that (may) have changed.  */
154  bitmap all_blocks;		/* All blocks in CFG.  */
155  int *dfs_order;		/* DFS order -> block number.  */
156  int *rc_order;		/* Reverse completion order -> block number.  */
157  int *rts_order;		/* Reverse top sort order -> block number.  */
158  int *inverse_rc_map;		/* Block number -> reverse completion order.  */
159  int *inverse_dfs_map;		/* Block number -> DFS order.  */
160  int *inverse_rts_map;		/* Block number -> reverse top-sort order.  */
161};
162
163
164struct df_map
165{
166  rtx old;
167  rtx new;
168};
169
170
171#define DF_BB_INFO(REFS, BB) (&REFS->bbs[(BB)->index])
172
173
174/* Macros to access the elements within the ref structure.  */
175
176#define DF_REF_REAL_REG(REF) (GET_CODE ((REF)->reg) == SUBREG \
177				? SUBREG_REG ((REF)->reg) : ((REF)->reg))
178#define DF_REF_REGNO(REF) REGNO (DF_REF_REAL_REG (REF))
179#define DF_REF_REAL_LOC(REF) (GET_CODE ((REF)->reg) == SUBREG \
180			        ? &SUBREG_REG ((REF)->reg) : ((REF)->loc))
181#define DF_REF_REG(REF) ((REF)->reg)
182#define DF_REF_LOC(REF) ((REF)->loc)
183#define DF_REF_BB(REF) (BLOCK_FOR_INSN ((REF)->insn))
184#define DF_REF_BBNO(REF) (BLOCK_FOR_INSN ((REF)->insn)->index)
185#define DF_REF_INSN(REF) ((REF)->insn)
186#define DF_REF_INSN_UID(REF) (INSN_UID ((REF)->insn))
187#define DF_REF_TYPE(REF) ((REF)->type)
188#define DF_REF_CHAIN(REF) ((REF)->chain)
189#define DF_REF_ID(REF) ((REF)->id)
190#define DF_REF_FLAGS(REF) ((REF)->flags)
191#define DF_REF_DATA(REF) ((REF)->data)
192
193/* Macros to determine the reference type.  */
194
195#define DF_REF_REG_DEF_P(REF) (DF_REF_TYPE (REF) == DF_REF_REG_DEF)
196#define DF_REF_REG_USE_P(REF) ((REF) && ! DF_REF_REG_DEF_P (REF))
197#define DF_REF_REG_MEM_STORE_P(REF) (DF_REF_TYPE (REF) == DF_REF_REG_MEM_STORE)
198#define DF_REF_REG_MEM_LOAD_P(REF) (DF_REF_TYPE (REF) == DF_REF_REG_MEM_LOAD)
199#define DF_REF_REG_MEM_P(REF) (DF_REF_REG_MEM_STORE_P (REF) \
200                               || DF_REF_REG_MEM_LOAD_P (REF))
201
202
203/* Macros to access the elements within the reg_info structure table.  */
204
205#define DF_REGNO_FIRST_DEF(DF, REGNUM) \
206((DF)->regs[REGNUM].defs ? (DF)->regs[REGNUM].defs->ref : 0)
207#define DF_REGNO_LAST_USE(DF, REGNUM) \
208((DF)->regs[REGNUM].uses ? (DF)->regs[REGNUM].uses->ref : 0)
209
210#define DF_REGNO_FIRST_BB(DF, REGNUM) \
211((DF)->regs[REGNUM].defs ? DF_REF_BB ((DF)->regs[REGNUM].defs->ref) : 0)
212#define DF_REGNO_LAST_BB(DF, REGNUM) \
213((DF)->regs[REGNUM].uses ? DF_REF_BB ((DF)->regs[REGNUM].uses->ref) : 0)
214
215
216/* Macros to access the elements within the insn_info structure table.  */
217
218#define DF_INSN_LUID(DF, INSN) ((DF)->insns[INSN_UID (INSN)].luid)
219#define DF_INSN_DEFS(DF, INSN) ((DF)->insns[INSN_UID (INSN)].defs)
220#define DF_INSN_USES(DF, INSN) ((DF)->insns[INSN_UID (INSN)].uses)
221
222
223/* Functions to build and analyze dataflow information.  */
224
225extern struct df *df_init (void);
226
227extern int df_analyze (struct df *, bitmap, int);
228extern void df_analyze_subcfg (struct df *, bitmap, int);
229
230extern void df_finish (struct df *);
231
232extern void df_dump (struct df *, int, FILE *);
233
234
235/* Functions to modify insns.  */
236
237extern bool df_insn_modified_p (struct df *, rtx);
238
239extern void df_insn_modify (struct df *, basic_block, rtx);
240
241extern rtx df_insn_delete (struct df *, basic_block, rtx);
242
243extern rtx df_pattern_emit_before (struct df *, rtx, basic_block, rtx);
244
245extern rtx df_jump_pattern_emit_after (struct df *, rtx, basic_block, rtx);
246
247extern rtx df_pattern_emit_after (struct df *, rtx, basic_block, rtx);
248
249extern rtx df_insn_move_before (struct df *, basic_block, rtx, basic_block,
250				rtx);
251
252extern int df_reg_replace (struct df *, bitmap, rtx, rtx);
253
254extern int df_ref_reg_replace (struct df *, struct ref *, rtx, rtx);
255
256extern int df_ref_remove (struct df *, struct ref *);
257
258extern int df_insn_mem_replace (struct df *, basic_block, rtx, rtx, rtx);
259
260extern struct ref *df_bb_def_use_swap (struct df *, basic_block, rtx, rtx,
261				       unsigned int);
262
263
264/* Functions to query dataflow information.  */
265
266extern basic_block df_regno_bb (struct df *, unsigned int);
267
268extern int df_reg_lifetime (struct df *, rtx);
269
270extern int df_reg_global_p (struct df *, rtx);
271
272extern int df_insn_regno_def_p (struct df *, basic_block, rtx, unsigned int);
273
274extern int df_insn_dominates_all_uses_p (struct df *, basic_block, rtx);
275
276extern int df_insn_dominates_uses_p (struct df *, basic_block, rtx, bitmap);
277
278extern int df_bb_reg_live_start_p (struct df *, basic_block, rtx);
279
280extern int df_bb_reg_live_end_p (struct df *, basic_block, rtx);
281
282extern int df_bb_regs_lives_compare (struct df *, basic_block, rtx, rtx);
283
284extern bool df_local_def_available_p (struct df *, struct ref *, struct ref *);
285
286extern rtx df_bb_single_def_use_insn_find (struct df *, basic_block, rtx,
287					   rtx);
288extern struct ref *df_bb_regno_last_use_find (struct df *, basic_block, unsigned int);
289
290extern struct ref *df_bb_regno_first_def_find (struct df *, basic_block, unsigned int);
291
292extern struct ref *df_bb_regno_last_def_find (struct df *, basic_block, unsigned int);
293
294extern struct ref *df_find_def (struct df *, rtx, rtx);
295
296extern int df_reg_used (struct df *, rtx, rtx);
297
298/* Functions for debugging from GDB.  */
299
300extern void debug_df_insn (rtx);
301
302extern void debug_df_regno (unsigned int);
303
304extern void debug_df_reg (rtx);
305
306extern void debug_df_defno (unsigned int);
307
308extern void debug_df_useno (unsigned int);
309
310extern void debug_df_ref (struct ref *);
311
312extern void debug_df_chain (struct df_link *);
313
314extern void df_insn_debug (struct df *, rtx, FILE *);
315
316extern void df_insn_debug_regno (struct df *, rtx, FILE *);
317
318
319/* Meet over any path (UNION) or meet over all paths (INTERSECTION).  */
320enum df_confluence_op
321  {
322    DF_UNION,
323    DF_INTERSECTION
324  };
325
326
327/* Dataflow direction.  */
328enum df_flow_dir
329  {
330    DF_FORWARD,
331    DF_BACKWARD
332  };
333
334
335typedef void (*transfer_function) (int, int *, void *, void *,
336				   void *, void *, void *);
337
338/* The description of a dataflow problem to solve.  */
339
340enum set_representation
341{
342  SR_SBITMAP,		/* Represent sets by bitmaps.  */
343  SR_BITMAP		/* Represent sets by sbitmaps.  */
344};
345
346struct dataflow
347{
348  enum set_representation repr;		/* The way the sets are represented.  */
349
350  /* The following arrays are indexed by block indices, so they must always
351     be large enough even if we restrict ourselves just to a subset of cfg.  */
352  void **gen, **kill;			/* Gen and kill sets.  */
353  void **in, **out;			/* Results.  */
354
355  enum df_flow_dir dir;			/* Dataflow direction.  */
356  enum df_confluence_op conf_op;	/* Confluence operator.  */
357  unsigned n_blocks;			/* Number of basic blocks in the
358					   order.  */
359  int *order;				/* The list of basic blocks to work
360					   with, in the order they should
361					   be processed in.  */
362  transfer_function transfun;		/* The transfer function.  */
363  void *data;				/* Data used by the transfer
364					   function.  */
365};
366
367extern void iterative_dataflow (struct dataflow *);
368extern bool read_modify_subreg_p (rtx);
369
370#endif /* GCC_DF_H */
371