gcc/basic-block.h

   1 /* Define control and data flow tables, and regsets.
   2    Copyright (C) 1987, 1997, 1998, 1999, 2000, 2001 Free Software Foundation, Inc.
   3
   4 This file is part of GNU CC.
   5
   6 GNU CC is free software; you can redistribute it and/or modify
   7 it under the terms of the GNU General Public License as published by
   8 the Free Software Foundation; either version 2, or (at your option)
   9 any later version.
  10
  11 GNU CC is distributed in the hope that it will be useful,
  12 but WITHOUT ANY WARRANTY; without even the implied warranty of
  13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14 GNU General Public License for more details.
  15
  16 You should have received a copy of the GNU General Public License
  17 along with GNU CC; see the file COPYING.  If not, write to
  18 the Free Software Foundation, 59 Temple Place - Suite 330,
  19 Boston, MA 02111-1307, USA.  */
  20
  21 #ifndef GCC_BASIC_BLOCK_H
  22 #define GCC_BASIC_BLOCK_H
  23
  24 #include "bitmap.h"
  25 #include "sbitmap.h"
  26 #include "varray.h"
  27 #include "partition.h"
  28
  29 /* Head of register set linked list.  */
  30 typedef bitmap_head regset_head;
  31 /* A pointer to a regset_head.  */
  32 typedef bitmap regset;
  33
  34 /* Initialize a new regset.  */
  35 #define INIT_REG_SET(HEAD) bitmap_initialize (HEAD)
  36
  37 /* Clear a register set by freeing up the linked list.  */
  38 #define CLEAR_REG_SET(HEAD) bitmap_clear (HEAD)
  39
  40 /* Copy a register set to another register set.  */
  41 #define COPY_REG_SET(TO, FROM) bitmap_copy (TO, FROM)
  42
  43 /* Compare two register sets.  */
  44 #define REG_SET_EQUAL_P(A, B) bitmap_equal_p (A, B)
  45
  46 /* `and' a register set with a second register set.  */
  47 #define AND_REG_SET(TO, FROM) bitmap_operation (TO, TO, FROM, BITMAP_AND)
  48
  49 /* `and' the complement of a register set with a register set.  */
  50 #define AND_COMPL_REG_SET(TO, FROM) \
  51   bitmap_operation (TO, TO, FROM, BITMAP_AND_COMPL)
  52
  53 /* Inclusive or a register set with a second register set.  */
  54 #define IOR_REG_SET(TO, FROM) bitmap_operation (TO, TO, FROM, BITMAP_IOR)
  55
  56 /* Exclusive or a register set with a second register set.  */
  57 #define XOR_REG_SET(TO, FROM) bitmap_operation (TO, TO, FROM, BITMAP_XOR)
  58
  59 /* Or into TO the register set FROM1 `and'ed with the complement of FROM2.  */
  60 #define IOR_AND_COMPL_REG_SET(TO, FROM1, FROM2) \
  61   bitmap_ior_and_compl (TO, FROM1, FROM2)
  62
  63 /* Clear a single register in a register set.  */
  64 #define CLEAR_REGNO_REG_SET(HEAD, REG) bitmap_clear_bit (HEAD, REG)
  65
  66 /* Set a single register in a register set.  */
  67 #define SET_REGNO_REG_SET(HEAD, REG) bitmap_set_bit (HEAD, REG)
  68
  69 /* Return true if a register is set in a register set.  */
  70 #define REGNO_REG_SET_P(TO, REG) bitmap_bit_p (TO, REG)
  71
  72 /* Copy the hard registers in a register set to the hard register set.  */
  73 extern void reg_set_to_hard_reg_set PARAMS ((HARD_REG_SET *, bitmap));
  74 #define REG_SET_TO_HARD_REG_SET(TO, FROM)                               \
  75 do {                                                                    \
  76   CLEAR_HARD_REG_SET (TO);                                              \
  77   reg_set_to_hard_reg_set (&TO, FROM);                                  \
  78 } while (0)
  79
  80 /* Loop over all registers in REGSET, starting with MIN, setting REGNUM to the
  81    register number and executing CODE for all registers that are set. */
  82 #define EXECUTE_IF_SET_IN_REG_SET(REGSET, MIN, REGNUM, CODE)            \
  83   EXECUTE_IF_SET_IN_BITMAP (REGSET, MIN, REGNUM, CODE)
  84
  85 /* Loop over all registers in REGSET1 and REGSET2, starting with MIN, setting
  86    REGNUM to the register number and executing CODE for all registers that are
  87    set in the first regset and not set in the second. */
  88 #define EXECUTE_IF_AND_COMPL_IN_REG_SET(REGSET1, REGSET2, MIN, REGNUM, CODE) \
  89   EXECUTE_IF_AND_COMPL_IN_BITMAP (REGSET1, REGSET2, MIN, REGNUM, CODE)
  90
  91 /* Loop over all registers in REGSET1 and REGSET2, starting with MIN, setting
  92    REGNUM to the register number and executing CODE for all registers that are
  93    set in both regsets. */
  94 #define EXECUTE_IF_AND_IN_REG_SET(REGSET1, REGSET2, MIN, REGNUM, CODE) \
  95   EXECUTE_IF_AND_IN_BITMAP (REGSET1, REGSET2, MIN, REGNUM, CODE)
  96
  97 /* Allocate a register set with oballoc.  */
  98 #define OBSTACK_ALLOC_REG_SET(OBSTACK) BITMAP_OBSTACK_ALLOC (OBSTACK)
  99
 100 /* Initialize a register set.  Returns the new register set.  */
 101 #define INITIALIZE_REG_SET(HEAD) bitmap_initialize (&HEAD)
 102
 103 /* Do any cleanup needed on a regset when it is no longer used.  */
 104 #define FREE_REG_SET(REGSET) BITMAP_FREE(REGSET)
 105
 106 /* Do any one-time initializations needed for regsets.  */
 107 #define INIT_ONCE_REG_SET() BITMAP_INIT_ONCE ()
 108
 109 /* Grow any tables needed when the number of registers is calculated
 110    or extended.  For the linked list allocation, nothing needs to
 111    be done, other than zero the statistics on the first allocation.  */
 112 #define MAX_REGNO_REG_SET(NUM_REGS, NEW_P, RENUMBER_P)
 113
 114 /* Control flow edge information.  */
 115 typedef struct edge_def {
 116   /* Links through the predecessor and successor lists.  */
 117   struct edge_def *pred_next, *succ_next;
 118
 119   /* The two blocks at the ends of the edge.  */
 120   struct basic_block_def *src, *dest;
 121
 122   /* Instructions queued on the edge.  */
 123   rtx insns;
 124
 125   /* Auxiliary info specific to a pass.  */
 126   void *aux;
 127
 128   int flags;                    /* see EDGE_* below  */
 129   int probability;              /* biased by REG_BR_PROB_BASE */
 130   int count;                    /* Expected number of executions calculated
 131                                    in profile.c  */
 132 } *edge;
 133
 134 #define EDGE_FALLTHRU           1
 135 #define EDGE_CRITICAL           2
 136 #define EDGE_ABNORMAL           4
 137 #define EDGE_ABNORMAL_CALL      8
 138 #define EDGE_EH                 16
 139 #define EDGE_FAKE               32
 140
 141 #define EDGE_COMPLEX    (EDGE_ABNORMAL | EDGE_ABNORMAL_CALL | EDGE_EH)
 142
 143
 144 /* A basic block is a sequence of instructions with only entry and
 145    only one exit.  If any one of the instructions are executed, they
 146    will all be executed, and in sequence from first to last.
 147
 148    There may be COND_EXEC instructions in the basic block.  The
 149    COND_EXEC *instructions* will be executed -- but if the condition
 150    is false the conditionally executed *expressions* will of course
 151    not be executed.  We don't consider the conditionally executed
 152    expression (which might have side-effects) to be in a separate
 153    basic block because the program counter will always be at the same
 154    location after the COND_EXEC instruction, regardless of whether the
 155    condition is true or not.
 156
 157    Basic blocks need not start with a label nor end with a jump insn.
 158    For example, a previous basic block may just "conditionally fall"
 159    into the succeeding basic block, and the last basic block need not
 160    end with a jump insn.  Block 0 is a descendant of the entry block.
 161
 162    A basic block beginning with two labels cannot have notes between
 163    the labels.
 164
 165    Data for jump tables are stored in jump_insns that occur in no
 166    basic block even though these insns can follow or precede insns in
 167    basic blocks.  */
 168
 169 /* Basic block information indexed by block number.  */
 170 typedef struct basic_block_def {
 171   /* The first and last insns of the block.  */
 172   rtx head, end;
 173
 174   /* The edges into and out of the block.  */
 175   edge pred, succ;
 176
 177   /* Liveness info.  */
 178
 179   /* The registers that are modified within this in block.  */
 180   regset local_set;
 181   /* The registers that are conditionally modified within this block.
 182      In other words, registers that are set only as part of a
 183      COND_EXEC.  */
 184   regset cond_local_set;
 185   /* The registers that are live on entry to this block.
 186
 187      Note that in SSA form, global_live_at_start does not reflect the
 188      use of regs in phi functions, since the liveness of these regs
 189      may depend on which edge was taken into the block.  */
 190   regset global_live_at_start;
 191   /* The registers that are live on exit from this block.  */
 192   regset global_live_at_end;
 193
 194   /* Auxiliary info specific to a pass.  */
 195   void *aux;
 196
 197   /* The index of this block.  */
 198   int index;
 199
 200   /* The loop depth of this block.  */
 201   int loop_depth;
 202
 203   /* Expected number of executions: calculated in profile.c.  */
 204   int count;
 205 } *basic_block;
 206
 207 /* Number of basic blocks in the current function.  */
 208
 209 extern int n_basic_blocks;
 210
 211 /* Number of edges in the current function.  */
 212
 213 extern int n_edges;
 214
 215 /* Index by basic block number, get basic block struct info.  */
 216
 217 extern varray_type basic_block_info;
 218
 219 #define BASIC_BLOCK(N)  (VARRAY_BB (basic_block_info, (N)))
 220
 221 /* What registers are live at the setjmp call.  */
 222
 223 extern regset regs_live_at_setjmp;
 224
 225 /* Indexed by n, gives number of basic block that  (REG n) is used in.
 226    If the value is REG_BLOCK_GLOBAL (-2),
 227    it means (REG n) is used in more than one basic block.
 228    REG_BLOCK_UNKNOWN (-1) means it hasn't been seen yet so we don't know.
 229    This information remains valid for the rest of the compilation
 230    of the current function; it is used to control register allocation.  */
 231
 232 #define REG_BLOCK_UNKNOWN -1
 233 #define REG_BLOCK_GLOBAL -2
 234
 235 #define REG_BASIC_BLOCK(N) (VARRAY_REG (reg_n_info, N)->basic_block)
 236 \f
 237 /* Stuff for recording basic block info.  */
 238
 239 #define BLOCK_HEAD(B)      (BASIC_BLOCK (B)->head)
 240 #define BLOCK_END(B)       (BASIC_BLOCK (B)->end)
 241
 242 /* Special block numbers [markers] for entry and exit.  */
 243 #define ENTRY_BLOCK (-1)
 244 #define EXIT_BLOCK (-2)
 245
 246 /* Special block number not valid for any block. */
 247 #define INVALID_BLOCK (-3)
 248
 249 /* Similarly, block pointers for the edge list.  */
 250 extern struct basic_block_def entry_exit_blocks[2];
 251 #define ENTRY_BLOCK_PTR (&entry_exit_blocks[0])
 252 #define EXIT_BLOCK_PTR  (&entry_exit_blocks[1])
 253
 254 extern varray_type basic_block_for_insn;
 255 #define BLOCK_FOR_INSN(INSN)  VARRAY_BB (basic_block_for_insn, INSN_UID (INSN))
 256 #define BLOCK_NUM(INSN)       (BLOCK_FOR_INSN (INSN)->index + 0)
 257
 258 extern void compute_bb_for_insn         PARAMS ((int));
 259 extern void update_bb_for_insn          PARAMS ((basic_block));
 260 extern void set_block_for_insn          PARAMS ((rtx, basic_block));
 261 extern void set_block_for_new_insns     PARAMS ((rtx, basic_block));
 262
 263 extern void free_basic_block_vars       PARAMS ((int));
 264
 265 extern edge split_block                 PARAMS ((basic_block, rtx));
 266 extern basic_block split_edge           PARAMS ((edge));
 267 extern void insert_insn_on_edge         PARAMS ((rtx, edge));
 268 extern void commit_edge_insertions      PARAMS ((void));
 269 extern void remove_fake_edges           PARAMS ((void));
 270 extern void add_noreturn_fake_exit_edges        PARAMS ((void));
 271 extern void connect_infinite_loops_to_exit      PARAMS ((void));
 272 extern int flow_call_edges_add          PARAMS ((sbitmap));
 273 extern rtx flow_delete_insn             PARAMS ((rtx));
 274 extern void flow_delete_insn_chain      PARAMS ((rtx, rtx));
 275 extern void make_edge                   PARAMS ((sbitmap *, basic_block,
 276                                                  basic_block, int));
 277 extern void remove_edge                 PARAMS ((edge));
 278 extern void redirect_edge_succ          PARAMS ((edge, basic_block));
 279 extern void redirect_edge_pred          PARAMS ((edge, basic_block));
 280 extern void create_basic_block          PARAMS ((int, rtx, rtx, rtx));
 281 extern int flow_delete_block            PARAMS ((basic_block));
 282 extern void merge_blocks_nomove         PARAMS ((basic_block, basic_block));
 283 extern void tidy_fallthru_edge          PARAMS ((edge, basic_block,
 284                                                  basic_block));
 285
 286 /* Structure to hold information for each natural loop.  */
 287 struct loop
 288 {
 289   /* Index into loops array.  */
 290   int num;
 291
 292   /* Basic block of loop header.  */
 293   basic_block header;
 294
 295   /* Basic block of loop latch.  */
 296   basic_block latch;
 297
 298   /* Basic block of loop pre-header or NULL if it does not exist.  */
 299   basic_block pre_header;
 300
 301   /* Array of edges along the pre-header extended basic block trace.
 302      The source of the first edge is the root node of pre-header
 303      extended basic block, if it exists.  */
 304   edge *pre_header_edges;
 305
 306   /* Number of edges along the pre_header extended basic block trace.  */
 307   int num_pre_header_edges;
 308
 309   /* The first block in the loop.  This is not necessarily the same as
 310      the loop header.  */
 311   basic_block first;
 312
 313   /* The last block in the loop.  This is not necessarily the same as
 314      the loop latch.  */
 315   basic_block last;
 316
 317   /* Bitmap of blocks contained within the loop.  */
 318   sbitmap nodes;
 319
 320   /* Number of blocks contained within the loop.  */
 321   int num_nodes;
 322
 323   /* Array of edges that enter the loop.  */
 324   edge *entry_edges;
 325
 326   /* Number of edges that enter the loop.  */
 327   int num_entries;
 328
 329   /* Array of edges that exit the loop.  */
 330   edge *exit_edges;
 331
 332   /* Number of edges that exit the loop.  */
 333   int num_exits;
 334
 335   /* Bitmap of blocks that dominate all exits of the loop.  */
 336   sbitmap exits_doms;
 337
 338   /* The loop nesting depth.  */
 339   int depth;
 340
 341   /* The height of the loop (enclosed loop levels) within the loop
 342      hierarchy tree.  */
 343   int level;
 344
 345   /* The outer (parent) loop or NULL if outermost loop.  */
 346   struct loop *outer;
 347
 348   /* The first inner (child) loop or NULL if innermost loop.  */
 349   struct loop *inner;
 350
 351   /* Link to the next (sibling) loop.  */
 352   struct loop *next;
 353
 354   /* Non-zero if the loop shares a header with another loop.  */
 355   int shared;
 356
 357   /* Non-zero if the loop is invalid (e.g., contains setjmp.).  */
 358   int invalid;
 359
 360   /* Auxiliary info specific to a pass.  */
 361   void *aux;
 362
 363   /* The following are currently used by loop.c but they are likely to
 364      disappear as loop.c is converted to use the CFG.  */
 365
 366   /* Non-zero if the loop has a NOTE_INSN_LOOP_VTOP.  */
 367   rtx vtop;
 368
 369   /* Non-zero if the loop has a NOTE_INSN_LOOP_CONT.
 370      A continue statement will generate a branch to NEXT_INSN (cont).  */
 371   rtx cont;
 372
 373   /* The dominator of cont.  */
 374   rtx cont_dominator;
 375
 376   /* The NOTE_INSN_LOOP_BEG.  */
 377   rtx start;
 378
 379   /* The NOTE_INSN_LOOP_END.  */
 380   rtx end;
 381
 382   /* For a rotated loop that is entered near the bottom,
 383      this is the label at the top.  Otherwise it is zero.  */
 384   rtx top;
 385
 386   /* Place in the loop where control enters.  */
 387   rtx scan_start;
 388
 389   /* The position where to sink insns out of the loop.  */
 390   rtx sink;
 391
 392   /* List of all LABEL_REFs which refer to code labels outside the
 393      loop.  Used by routines that need to know all loop exits, such as
 394      final_biv_value and final_giv_value.
 395
 396      This does not include loop exits due to return instructions.
 397      This is because all bivs and givs are pseudos, and hence must be
 398      dead after a return, so the presense of a return does not affect
 399      any of the optimizations that use this info.  It is simpler to
 400      just not include return instructions on this list.  */
 401   rtx exit_labels;
 402
 403   /* The number of LABEL_REFs on exit_labels for this loop and all
 404      loops nested inside it.  */
 405   int exit_count;
 406 };
 407
 408
 409 /* Structure to hold CFG information about natural loops within a function.  */
 410 struct loops
 411 {
 412   /* Number of natural loops in the function.  */
 413   int num;
 414
 415   /* Maxium nested loop level in the function.  */
 416   int levels;
 417
 418   /* Array of natural loop descriptors (scanning this array in reverse order
 419      will find the inner loops before their enclosing outer loops).  */
 420   struct loop *array;
 421
 422   /* Pointer to root of loop heirachy tree.  */
 423   struct loop *tree;
 424
 425   /* Information derived from the CFG.  */
 426   struct cfg
 427   {
 428     /* The bitmap vector of dominators or NULL if not computed.  */
 429     sbitmap *dom;
 430
 431     /* The ordering of the basic blocks in a depth first search.  */
 432     int *dfs_order;
 433
 434     /* The reverse completion ordering of the basic blocks found in a
 435        depth first search.  */
 436     int *rc_order;
 437   } cfg;
 438
 439   /* Headers shared by multiple loops that should be merged.  */
 440   sbitmap shared_headers;
 441 };
 442
 443 extern int flow_loops_find PARAMS ((struct loops *, int flags));
 444 extern int flow_loops_update PARAMS ((struct loops *, int flags));
 445 extern void flow_loops_free PARAMS ((struct loops *));
 446 extern void flow_loops_dump PARAMS ((const struct loops *, FILE *,
 447                                      void (*)(const struct loop *,
 448                                               FILE *, int), int));
 449 extern void flow_loop_dump PARAMS ((const struct loop *, FILE *,
 450                                     void (*)(const struct loop *,
 451                                              FILE *, int), int));
 452 extern int flow_loop_scan PARAMS ((struct loops *, struct loop *, int));
 453
 454 /* This structure maintains an edge list vector.  */
 455 struct edge_list
 456 {
 457   int num_blocks;
 458   int num_edges;
 459   edge *index_to_edge;
 460 };
 461
 462 /* This is the value which indicates no edge is present.  */
 463 #define EDGE_INDEX_NO_EDGE      -1
 464
 465 /* EDGE_INDEX returns an integer index for an edge, or EDGE_INDEX_NO_EDGE
 466    if there is no edge between the 2 basic blocks.  */
 467 #define EDGE_INDEX(el, pred, succ) (find_edge_index ((el), (pred), (succ)))
 468
 469 /* INDEX_EDGE_PRED_BB and INDEX_EDGE_SUCC_BB return a pointer to the basic
 470    block which is either the pred or succ end of the indexed edge.  */
 471 #define INDEX_EDGE_PRED_BB(el, index)   ((el)->index_to_edge[(index)]->src)
 472 #define INDEX_EDGE_SUCC_BB(el, index)   ((el)->index_to_edge[(index)]->dest)
 473
 474 /* INDEX_EDGE returns a pointer to the edge.  */
 475 #define INDEX_EDGE(el, index)           ((el)->index_to_edge[(index)])
 476
 477 /* Number of edges in the compressed edge list.  */
 478 #define NUM_EDGES(el)                   ((el)->num_edges)
 479
 480 struct edge_list * create_edge_list     PARAMS ((void));
 481 void free_edge_list                     PARAMS ((struct edge_list *));
 482 void print_edge_list                    PARAMS ((FILE *, struct edge_list *));
 483 void verify_edge_list                   PARAMS ((FILE *, struct edge_list *));
 484 int find_edge_index                     PARAMS ((struct edge_list *,
 485                                                  basic_block, basic_block));
 486
 487
 488 enum update_life_extent
 489 {
 490   UPDATE_LIFE_LOCAL = 0,
 491   UPDATE_LIFE_GLOBAL = 1,
 492   UPDATE_LIFE_GLOBAL_RM_NOTES = 2
 493 };
 494
 495 /* Flags for life_analysis and update_life_info.  */
 496
 497 #define PROP_DEATH_NOTES        1       /* Create DEAD and UNUSED notes.  */
 498 #define PROP_LOG_LINKS          2       /* Create LOG_LINKS.  */
 499 #define PROP_REG_INFO           4       /* Update regs_ever_live et al.  */
 500 #define PROP_KILL_DEAD_CODE     8       /* Remove dead code.  */
 501 #define PROP_SCAN_DEAD_CODE     16      /* Scan for dead code.  */
 502 #define PROP_AUTOINC            32      /* Create autoinc mem references.  */
 503 #define PROP_FINAL              63      /* All of the above.  */
 504
 505 /* Flags for loop discovery.  */
 506
 507 #define LOOP_TREE               1       /* Build loop hierarchy tree.  */
 508 #define LOOP_PRE_HEADER         2       /* Analyse loop pre-header.  */
 509 #define LOOP_ENTRY_EDGES        4       /* Find entry edges.  */
 510 #define LOOP_EXIT_EDGES         8       /* Find exit edges.  */
 511 #define LOOP_EDGES              (LOOP_ENTRY_EDGES | LOOP_EXIT_EDGES)
 512 #define LOOP_EXITS_DOMS        16       /* Find nodes that dom. all exits.  */
 513 #define LOOP_ALL               31       /* All of the above  */
 514
 515 extern void life_analysis       PARAMS ((rtx, FILE *, int));
 516 extern void update_life_info    PARAMS ((sbitmap, enum update_life_extent,
 517                                          int));
 518 extern int count_or_remove_death_notes  PARAMS ((sbitmap, int));
 519 extern void propagate_block     PARAMS ((basic_block, regset, regset, regset,
 520                                          int));
 521
 522 struct propagate_block_info;
 523 extern rtx propagate_one_insn   PARAMS ((struct propagate_block_info *, rtx));
 524 extern struct propagate_block_info *init_propagate_block_info
 525   PARAMS ((basic_block, regset, regset, regset, int));
 526 extern void free_propagate_block_info PARAMS ((struct propagate_block_info *));
 527
 528 /* In lcm.c */
 529 extern struct edge_list *pre_edge_lcm   PARAMS ((FILE *, int, sbitmap *,
 530                                                  sbitmap *, sbitmap *,
 531                                                  sbitmap *, sbitmap **,
 532                                                  sbitmap **));
 533 extern struct edge_list *pre_edge_rev_lcm PARAMS ((FILE *, int, sbitmap *,
 534                                                    sbitmap *, sbitmap *,
 535                                                    sbitmap *, sbitmap **,
 536                                                    sbitmap **));
 537 extern void compute_available           PARAMS ((sbitmap *, sbitmap *,
 538                                                  sbitmap *, sbitmap *));
 539 extern int optimize_mode_switching      PARAMS ((FILE *));
 540
 541 /* In emit-rtl.c.  */
 542 extern rtx emit_block_insn_after        PARAMS ((rtx, rtx, basic_block));
 543 extern rtx emit_block_insn_before       PARAMS ((rtx, rtx, basic_block));
 544
 545 /* In predict.c */
 546 extern void estimate_probability        PARAMS ((struct loops *));
 547 extern void expected_value_to_br_prob   PARAMS ((void));
 548
 549 /* In flow.c */
 550 extern void init_flow                   PARAMS ((void));
 551 extern void reorder_basic_blocks        PARAMS ((void));
 552 extern void dump_bb                     PARAMS ((basic_block, FILE *));
 553 extern void debug_bb                    PARAMS ((basic_block));
 554 extern void debug_bb_n                  PARAMS ((int));
 555 extern void dump_regset                 PARAMS ((regset, FILE *));
 556 extern void debug_regset                PARAMS ((regset));
 557 extern void allocate_reg_life_data      PARAMS ((void));
 558 extern void find_unreachable_blocks     PARAMS ((void));
 559
 560 /* This function is always defined so it can be called from the
 561    debugger, and it is declared extern so we don't get warnings about
 562    it being unused. */
 563 extern void verify_flow_info            PARAMS ((void));
 564 extern int flow_loop_outside_edge_p     PARAMS ((const struct loop *, edge));
 565
 566 typedef struct conflict_graph_def *conflict_graph;
 567
 568 /* Callback function when enumerating conflicts.  The arguments are
 569    the smaller and larger regno in the conflict.  Returns zero if
 570    enumeration is to continue, non-zero to halt enumeration.  */
 571 typedef int (*conflict_graph_enum_fn) PARAMS ((int, int, void *));
 572
 573
 574 /* Prototypes of operations on conflict graphs.  */
 575
 576 extern conflict_graph conflict_graph_new
 577                                         PARAMS ((int));
 578 extern void conflict_graph_delete       PARAMS ((conflict_graph));
 579 extern int conflict_graph_add           PARAMS ((conflict_graph,
 580                                                  int, int));
 581 extern int conflict_graph_conflict_p    PARAMS ((conflict_graph,
 582                                                  int, int));
 583 extern void conflict_graph_enum         PARAMS ((conflict_graph, int,
 584                                                  conflict_graph_enum_fn,
 585                                                  void *));
 586 extern void conflict_graph_merge_regs   PARAMS ((conflict_graph, int,
 587                                                  int));
 588 extern void conflict_graph_print        PARAMS ((conflict_graph, FILE*));
 589 extern conflict_graph conflict_graph_compute
 590                                         PARAMS ((regset,
 591                                                  partition));
 592
 593 /* In dominance.c */
 594
 595 enum cdi_direction
 596 {
 597   CDI_DOMINATORS,
 598   CDI_POST_DOMINATORS
 599 };
 600
 601 extern void calculate_dominance_info    PARAMS ((int *, sbitmap *,
 602                                                  enum cdi_direction));
 603
 604 #endif /* GCC_BASIC_BLOCK_H */