gcc/df.h

   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 Free Software Foundation, Inc.
   4    Contributed by Michael P. Hayes (m.hayes@elec.canterbury.ac.nz)
   5
   6 This file is part of GCC.
   7
   8 GCC is free software; you can redistribute it and/or modify it under
   9 the terms of the GNU General Public License as published by the Free
  10 Software Foundation; either version 2, or (at your option) any later
  11 version.
  12
  13 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
  14 WARRANTY; without even the implied warranty of MERCHANTABILITY or
  15 FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  16 for more details.
  17
  18 You should have received a copy of the GNU General Public License
  19 along with GCC; see the file COPYING.  If not, write to the Free
  20 Software Foundation, 59 Temple Place - Suite 330, Boston, MA
  21 02111-1307, USA.  */
  22
  23 #define DF_RD            1      /* Reaching definitions.  */
  24 #define DF_RU            2      /* Reaching uses.  */
  25 #define DF_LR            4      /* Live registers.  */
  26 #define DF_DU_CHAIN      8      /* Def-use chain.  */
  27 #define DF_UD_CHAIN     16      /* Use-def chain.  */
  28 #define DF_REG_INFO     32      /* Register info.  */
  29 #define DF_RD_CHAIN     64      /* Reg-def chain.  */
  30 #define DF_RU_CHAIN    128      /* Reg-use chain.  */
  31 #define DF_ALL         255
  32 #define DF_HARD_REGS  1024      /* Mark hard registers.  */
  33 #define DF_EQUIV_NOTES 2048     /* Mark uses present in EQUIV/EQUAL notes.  */
  34 #define DF_FOR_REGALLOC 4096    /* If called for the register allocator.  */
  35
  36 enum df_ref_type {DF_REF_REG_DEF, DF_REF_REG_USE, DF_REF_REG_MEM_LOAD,
  37                   DF_REF_REG_MEM_STORE};
  38
  39 #define DF_REF_TYPE_NAMES {"def", "use", "mem load", "mem store"}
  40
  41 /* Link on a def-use or use-def chain.  */
  42 struct df_link
  43 {
  44   struct df_link *next;
  45   struct ref *ref;
  46 };
  47
  48 enum df_ref_flags
  49   {
  50     /* Read-modify-write refs generate both a use and a def and
  51        these are marked with this flag to show that they are not
  52        independent.  */
  53     DF_REF_READ_WRITE = 1,
  54
  55     /* This flag is set on register references inside a subreg on
  56        machines which have CANNOT_CHANGE_MODE_CLASS.
  57        Note, that this flag can also be set on df_refs representing
  58        the REG itself (i.e., one might not see the subreg anyore).
  59        Also note, that this flag is set also for hardreg refs, i.e.,
  60        you must check yourself if it's a pseudo.  */
  61     DF_REF_MODE_CHANGE = 2,
  62
  63     /* This flag is set, if we stripped the subreg from the reference.
  64        In this case we must make conservative guesses, at what the
  65        outer mode was.  */
  66     DF_REF_STRIPPED = 4
  67   };
  68
  69
  70 /* Define a register reference structure.  One of these is allocated
  71    for every register reference (use or def).  Note some register
  72    references (e.g., post_inc, subreg) generate both a def and a use.  */
  73 struct ref
  74 {
  75   rtx reg;                      /* The register referenced.  */
  76   rtx insn;                     /* Insn containing ref.  */
  77   rtx *loc;                     /* The location of the reg.  */
  78   struct df_link *chain;        /* Head of def-use or use-def chain.  */
  79   unsigned int id;              /* Ref index.  */
  80   enum df_ref_type type;        /* Type of ref.  */
  81   enum df_ref_flags flags;      /* Various flags.  */
  82 };
  83
  84
  85 /* One of these structures is allocated for every insn.  */
  86 struct 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 considerd 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.  */
  97 struct 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.  */
 108 struct 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
 131 struct 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   /* The sbitmap vector of dominators or NULL if not computed.
 156      Ideally, this should be a pointer to a CFG object.  */
 157   sbitmap *dom;
 158   int *dfs_order;               /* DFS order -> block number.  */
 159   int *rc_order;                /* Reverse completion order -> block number.  */
 160   int *rts_order;               /* Reverse top sort order -> block number.  */
 161   int *inverse_rc_map;          /* Block number -> reverse completion order.  */
 162   int *inverse_dfs_map;         /* Block number -> DFS order.  */
 163   int *inverse_rts_map;         /* Block number -> reverse top-sort order.  */
 164 };
 165
 166
 167 struct df_map
 168 {
 169   rtx old;
 170   rtx new;
 171 };
 172
 173
 174 #define DF_BB_INFO(REFS, BB) (&REFS->bbs[(BB)->index])
 175
 176
 177 /* Macros to access the elements within the ref structure.  */
 178
 179 #define DF_REF_REAL_REG(REF) (GET_CODE ((REF)->reg) == SUBREG \
 180                                 ? SUBREG_REG ((REF)->reg) : ((REF)->reg))
 181 #define DF_REF_REGNO(REF) REGNO (DF_REF_REAL_REG (REF))
 182 #define DF_REF_REAL_LOC(REF) (GET_CODE ((REF)->reg) == SUBREG \
 183                                 ? &SUBREG_REG ((REF)->reg) : ((REF)->loc))
 184 #define DF_REF_REG(REF) ((REF)->reg)
 185 #define DF_REF_LOC(REF) ((REF)->loc)
 186 #define DF_REF_BB(REF) (BLOCK_FOR_INSN ((REF)->insn))
 187 #define DF_REF_BBNO(REF) (BLOCK_FOR_INSN ((REF)->insn)->index)
 188 #define DF_REF_INSN(REF) ((REF)->insn)
 189 #define DF_REF_INSN_UID(REF) (INSN_UID ((REF)->insn))
 190 #define DF_REF_TYPE(REF) ((REF)->type)
 191 #define DF_REF_CHAIN(REF) ((REF)->chain)
 192 #define DF_REF_ID(REF) ((REF)->id)
 193 #define DF_REF_FLAGS(REF) ((REF)->flags)
 194
 195 /* Macros to determine the reference type.  */
 196
 197 #define DF_REF_REG_DEF_P(REF) (DF_REF_TYPE (REF) == DF_REF_REG_DEF)
 198 #define DF_REF_REG_USE_P(REF) ((REF) && ! DF_REF_REG_DEF_P (REF))
 199 #define DF_REF_REG_MEM_STORE_P(REF) (DF_REF_TYPE (REF) == DF_REF_REG_MEM_STORE)
 200 #define DF_REF_REG_MEM_LOAD_P(REF) (DF_REF_TYPE (REF) == DF_REF_REG_MEM_LOAD)
 201 #define DF_REF_REG_MEM_P(REF) (DF_REF_REG_MEM_STORE_P (REF) \
 202                                || DF_REF_REG_MEM_LOAD_P (REF))
 203
 204
 205 /* Macros to access the elements within the reg_info structure table.  */
 206
 207 #define DF_REGNO_FIRST_DEF(DF, REGNUM) \
 208 ((DF)->regs[REGNUM].defs ? (DF)->regs[REGNUM].defs->ref : 0)
 209 #define DF_REGNO_LAST_USE(DF, REGNUM) \
 210 ((DF)->regs[REGNUM].uses ? (DF)->regs[REGNUM].uses->ref : 0)
 211
 212 #define DF_REGNO_FIRST_BB(DF, REGNUM) \
 213 (DF_REGNO_FIRST_DEF (DF, REGNUM) \
 214 ? DF_REF_BB (DF_REGNO_FIRST_DEF (DF, REGNUM)) : 0)
 215 #define DF_REGNO_LAST_BB(DF, REGNUM) \
 216 (DF_REGNO_LAST_USE (DF, REGNUM) \
 217 ? DF_REF_BB (DF_REGNO_LAST_USE (DF, REGNUM)) : 0)
 218
 219
 220 /* Macros to access the elements within the insn_info structure table.  */
 221
 222 #define DF_INSN_LUID(DF, INSN) ((DF)->insns[INSN_UID (INSN)].luid)
 223 #define DF_INSN_DEFS(DF, INSN) ((DF)->insns[INSN_UID (INSN)].defs)
 224 #define DF_INSN_USES(DF, INSN) ((DF)->insns[INSN_UID (INSN)].uses)
 225
 226
 227 /* Functions to build and analyse dataflow information.  */
 228
 229 extern struct df *df_init PARAMS ((void));
 230
 231 extern int df_analyse PARAMS ((struct df *, bitmap, int));
 232
 233 extern void df_finish PARAMS ((struct df *));
 234
 235 extern void df_dump PARAMS ((struct df *, int, FILE *));
 236
 237
 238 /* Functions to modify insns.  */
 239
 240 extern void df_insn_modify PARAMS ((struct df *, basic_block, rtx));
 241
 242 extern rtx df_insn_delete PARAMS ((struct df *, basic_block, rtx));
 243
 244 extern rtx df_pattern_emit_before PARAMS ((struct df *, rtx,
 245                                            basic_block, rtx));
 246
 247 extern rtx df_jump_pattern_emit_after PARAMS ((struct df *, rtx,
 248                                                basic_block, rtx));
 249
 250 extern rtx df_pattern_emit_after PARAMS ((struct df *, rtx,
 251                                           basic_block, rtx));
 252
 253 extern rtx df_insn_move_before PARAMS ((struct df *, basic_block, rtx,
 254                                         basic_block, rtx));
 255
 256 extern int df_reg_replace PARAMS ((struct df *, bitmap, rtx, rtx));
 257
 258 extern int df_ref_reg_replace PARAMS ((struct df *, struct ref *, rtx, rtx));
 259
 260 extern int df_ref_remove PARAMS ((struct df *, struct ref *));
 261
 262 extern int df_insn_reg_replace PARAMS ((struct df *, basic_block,
 263                                         rtx, rtx, rtx));
 264
 265 extern int df_insn_mem_replace PARAMS ((struct df *, basic_block,
 266                                         rtx, rtx, rtx));
 267
 268 extern struct ref *df_bb_def_use_swap PARAMS ((struct df *, basic_block,
 269                                                rtx, rtx, unsigned int));
 270
 271
 272 /* Functions to query dataflow information.  */
 273
 274 extern basic_block df_regno_bb PARAMS((struct df *, unsigned int));
 275
 276 extern int df_reg_lifetime PARAMS ((struct df *, rtx));
 277
 278 extern int df_reg_global_p PARAMS ((struct df *, rtx));
 279
 280 extern int df_insn_regno_def_p PARAMS ((struct df *,
 281                                         basic_block, rtx, unsigned int));
 282
 283 extern int df_insn_dominates_all_uses_p PARAMS ((struct df *,
 284                                                  basic_block, rtx));
 285
 286 extern int df_insn_dominates_uses_p PARAMS ((struct df *, basic_block,
 287                                              rtx, bitmap));
 288
 289 extern int df_bb_reg_live_start_p PARAMS ((struct df *, basic_block, rtx));
 290
 291 extern int df_bb_reg_live_end_p PARAMS ((struct df *, basic_block, rtx));
 292
 293 extern int df_bb_regs_lives_compare PARAMS ((struct df *, basic_block,
 294                                              rtx, rtx));
 295
 296 extern rtx df_bb_single_def_use_insn_find PARAMS((struct df *, basic_block,
 297                                                   rtx, rtx));
 298
 299
 300 /* Functions for debugging from GDB.  */
 301
 302 extern void debug_df_insn PARAMS ((rtx));
 303
 304 extern void debug_df_regno PARAMS ((unsigned int));
 305
 306 extern void debug_df_reg PARAMS ((rtx));
 307
 308 extern void debug_df_defno PARAMS ((unsigned int));
 309
 310 extern void debug_df_useno PARAMS ((unsigned int));
 311
 312 extern void debug_df_ref PARAMS ((struct ref *));
 313
 314 extern void debug_df_chain PARAMS ((struct df_link *));
 315
 316 extern void df_insn_debug PARAMS ((struct df *, rtx, FILE *));
 317
 318 extern void df_insn_debug_regno PARAMS ((struct df *, rtx, FILE *));
 319
 320
 321 /* Meet over any path (UNION) or meet over all paths (INTERSECTION).  */
 322 enum df_confluence_op
 323   {
 324     DF_UNION,
 325     DF_INTERSECTION
 326   };
 327
 328
 329 /* Dataflow direction.  */
 330 enum df_flow_dir
 331   {
 332     DF_FORWARD,
 333     DF_BACKWARD
 334   };
 335
 336
 337 typedef void (*transfer_function_sbitmap) PARAMS ((int, int *, sbitmap, sbitmap,
 338                                                    sbitmap, sbitmap, void *));
 339
 340 typedef void (*transfer_function_bitmap) PARAMS ((int, int *, bitmap, bitmap,
 341                                                   bitmap, bitmap, void *));
 342
 343 extern void iterative_dataflow_sbitmap PARAMS ((sbitmap *, sbitmap *,
 344                                                 sbitmap *, sbitmap *,
 345                                                 bitmap, enum df_flow_dir,
 346                                                 enum df_confluence_op,
 347                                                 transfer_function_sbitmap,
 348                                                 int *, void *));
 349
 350 extern void iterative_dataflow_bitmap PARAMS ((bitmap *, bitmap *, bitmap *,
 351                                                bitmap *, bitmap,
 352                                                enum df_flow_dir,
 353                                                enum df_confluence_op,
 354                                                transfer_function_bitmap,
 355                                                int *, void *));
 356 extern bool read_modify_subreg_p PARAMS ((rtx));