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 /* Type we use to hold basic block counters.  Should be at least 64bit.  */
 115 typedef HOST_WIDEST_INT gcov_type;
 116
 117 /* Control flow edge information.  */
 118 typedef struct edge_def {
 119   /* Links through the predecessor and successor lists.  */
 120   struct edge_def *pred_next, *succ_next;
 121
 122   /* The two blocks at the ends of the edge.  */
 123   struct basic_block_def *src, *dest;
 124
 125   /* Instructions queued on the edge.  */
 126   rtx insns;
 127
 128   /* Auxiliary info specific to a pass.  */
 129   void *aux;
 130
 131   int flags;                    /* see EDGE_* below  */
 132   int probability;              /* biased by REG_BR_PROB_BASE */
 133   gcov_type count;              /* Expected number of executions calculated
 134                                    in profile.c  */
 135 } *edge;
 136
 137 #define EDGE_FALLTHRU           1
 138 #define EDGE_CRITICAL           2
 139 #define EDGE_ABNORMAL           4
 140 #define EDGE_ABNORMAL_CALL      8
 141 #define EDGE_EH                 16
 142 #define EDGE_FAKE               32
 143
 144 #define EDGE_COMPLEX    (EDGE_ABNORMAL | EDGE_ABNORMAL_CALL | EDGE_EH)
 145
 146
 147 /* A basic block is a sequence of instructions with only entry and
 148    only one exit.  If any one of the instructions are executed, they
 149    will all be executed, and in sequence from first to last.
 150
 151    There may be COND_EXEC instructions in the basic block.  The
 152    COND_EXEC *instructions* will be executed -- but if the condition
 153    is false the conditionally executed *expressions* will of course
 154    not be executed.  We don't consider the conditionally executed
 155    expression (which might have side-effects) to be in a separate
 156    basic block because the program counter will always be at the same
 157    location after the COND_EXEC instruction, regardless of whether the
 158    condition is true or not.
 159
 160    Basic blocks need not start with a label nor end with a jump insn.
 161    For example, a previous basic block may just "conditionally fall"
 162    into the succeeding basic block, and the last basic block need not
 163    end with a jump insn.  Block 0 is a descendant of the entry block.
 164
 165    A basic block beginning with two labels cannot have notes between
 166    the labels.
 167
 168    Data for jump tables are stored in jump_insns that occur in no
 169    basic block even though these insns can follow or precede insns in
 170    basic blocks.  */
 171
 172 /* Basic block information indexed by block number.  */
 173 typedef struct basic_block_def {
 174   /* The first and last insns of the block.  */
 175   rtx head, end;
 176
 177   /* The edges into and out of the block.  */
 178   edge pred, succ;
 179
 180   /* Liveness info.  */
 181
 182   /* The registers that are modified within this in block.  */
 183   regset local_set;
 184   /* The registers that are conditionally modified within this block.
 185      In other words, registers that are set only as part of a
 186      COND_EXEC.  */
 187   regset cond_local_set;
 188   /* The registers that are live on entry to this block.
 189
 190      Note that in SSA form, global_live_at_start does not reflect the
 191      use of regs in phi functions, since the liveness of these regs
 192      may depend on which edge was taken into the block.  */
 193   regset global_live_at_start;
 194   /* The registers that are live on exit from this block.  */
 195   regset global_live_at_end;
 196
 197   /* Auxiliary info specific to a pass.  */
 198   void *aux;
 199
 200   /* The index of this block.  */
 201   int index;
 202
 203   /* The loop depth of this block.  */
 204   int loop_depth;
 205
 206   /* Expected number of executions: calculated in profile.c.  */
 207   gcov_type count;
 208
 209   /* Expected frequency.  Normalized to be in range 0 to BB_FREQ_MAX.  */
 210   int frequency;
 211 } *basic_block;
 212
 213 #define BB_FREQ_MAX 10000
 214
 215 /* Number of basic blocks in the current function.  */
 216
 217 extern int n_basic_blocks;
 218
 219 /* Number of edges in the current function.  */
 220
 221 extern int n_edges;
 222
 223 /* Index by basic block number, get basic block struct info.  */
 224
 225 extern varray_type basic_block_info;
 226
 227 #define BASIC_BLOCK(N)  (VARRAY_BB (basic_block_info, (N)))
 228
 229 /* What registers are live at the setjmp call.  */
 230
 231 extern regset regs_live_at_setjmp;
 232
 233 /* Indexed by n, gives number of basic block that  (REG n) is used in.
 234    If the value is REG_BLOCK_GLOBAL (-2),
 235    it means (REG n) is used in more than one basic block.
 236    REG_BLOCK_UNKNOWN (-1) means it hasn't been seen yet so we don't know.
 237    This information remains valid for the rest of the compilation
 238    of the current function; it is used to control register allocation.  */
 239
 240 #define REG_BLOCK_UNKNOWN -1
 241 #define REG_BLOCK_GLOBAL -2
 242
 243 #define REG_BASIC_BLOCK(N) (VARRAY_REG (reg_n_info, N)->basic_block)
 244 \f
 245 /* Stuff for recording basic block info.  */
 246
 247 #define BLOCK_HEAD(B)      (BASIC_BLOCK (B)->head)
 248 #define BLOCK_END(B)       (BASIC_BLOCK (B)->end)
 249
 250 /* Special block numbers [markers] for entry and exit.  */
 251 #define ENTRY_BLOCK (-1)
 252 #define EXIT_BLOCK (-2)
 253
 254 /* Special block number not valid for any block. */
 255 #define INVALID_BLOCK (-3)
 256
 257 /* Similarly, block pointers for the edge list.  */
 258 extern struct basic_block_def entry_exit_blocks[2];
 259 #define ENTRY_BLOCK_PTR (&entry_exit_blocks[0])
 260 #define EXIT_BLOCK_PTR  (&entry_exit_blocks[1])
 261
 262 extern varray_type basic_block_for_insn;
 263 #define BLOCK_FOR_INSN(INSN)  VARRAY_BB (basic_block_for_insn, INSN_UID (INSN))
 264 #define BLOCK_NUM(INSN)       (BLOCK_FOR_INSN (INSN)->index + 0)
 265
 266 extern void compute_bb_for_insn         PARAMS ((int));
 267 extern void update_bb_for_insn          PARAMS ((basic_block));
 268 extern void set_block_for_insn          PARAMS ((rtx, basic_block));
 269 extern void set_block_for_new_insns     PARAMS ((rtx, basic_block));
 270
 271 extern void free_basic_block_vars       PARAMS ((int));
 272
 273 extern edge split_block                 PARAMS ((basic_block, rtx));
 274 extern basic_block split_edge           PARAMS ((edge));
 275 extern void insert_insn_on_edge         PARAMS ((rtx, edge));
 276 extern void commit_edge_insertions      PARAMS ((void));
 277 extern void remove_fake_edges           PARAMS ((void));
 278 extern void add_noreturn_fake_exit_edges        PARAMS ((void));
 279 extern void connect_infinite_loops_to_exit      PARAMS ((void));
 280 extern int flow_call_edges_add          PARAMS ((sbitmap));
 281 extern rtx flow_delete_insn             PARAMS ((rtx));
 282 extern void flow_delete_insn_chain      PARAMS ((rtx, rtx));
 283 extern void make_edge                   PARAMS ((sbitmap *, basic_block,
 284                                                  basic_block, int));
 285 extern void remove_edge                 PARAMS ((edge));
 286 extern void redirect_edge_succ          PARAMS ((edge, basic_block));
 287 extern void redirect_edge_pred          PARAMS ((edge, basic_block));
 288 extern void create_basic_block          PARAMS ((int, rtx, rtx, rtx));
 289 extern int flow_delete_block            PARAMS ((basic_block));
 290 extern void merge_blocks_nomove         PARAMS ((basic_block, basic_block));
 291 extern void tidy_fallthru_edge          PARAMS ((edge, basic_block,
 292                                                  basic_block));
 293 extern int flow_depth_first_order_compute       PARAMS ((int *, int *));
 294 extern void dump_edge_info              PARAMS ((FILE *, edge, int));
 295 extern void clear_edges                 PARAMS ((void));
 296 extern void mark_critical_edges         PARAMS ((void));
 297 extern rtx first_insn_after_basic_block_note    PARAMS ((basic_block));
 298
 299 /* Structure to hold information for each natural loop.  */
 300 struct loop
 301 {
 302   /* Index into loops array.  */
 303   int num;
 304
 305   /* Basic block of loop header.  */
 306   basic_block header;
 307
 308   /* Basic block of loop latch.  */
 309   basic_block latch;
 310
 311   /* Basic block of loop pre-header or NULL if it does not exist.  */
 312   basic_block pre_header;
 313
 314   /* Array of edges along the pre-header extended basic block trace.
 315      The source of the first edge is the root node of pre-header
 316      extended basic block, if it exists.  */
 317   edge *pre_header_edges;
 318
 319   /* Number of edges along the pre_header extended basic block trace.  */
 320   int num_pre_header_edges;
 321
 322   /* The first block in the loop.  This is not necessarily the same as
 323      the loop header.  */
 324   basic_block first;
 325
 326   /* The last block in the loop.  This is not necessarily the same as
 327      the loop latch.  */
 328   basic_block last;
 329
 330   /* Bitmap of blocks contained within the loop.  */
 331   sbitmap nodes;
 332
 333   /* Number of blocks contained within the loop.  */
 334   int num_nodes;
 335
 336   /* Array of edges that enter the loop.  */
 337   edge *entry_edges;
 338
 339   /* Number of edges that enter the loop.  */
 340   int num_entries;
 341
 342   /* Array of edges that exit the loop.  */
 343   edge *exit_edges;
 344
 345   /* Number of edges that exit the loop.  */
 346   int num_exits;
 347
 348   /* Bitmap of blocks that dominate all exits of the loop.  */
 349   sbitmap exits_doms;
 350
 351   /* The loop nesting depth.  */
 352   int depth;
 353
 354   /* The height of the loop (enclosed loop levels) within the loop
 355      hierarchy tree.  */
 356   int level;
 357
 358   /* The outer (parent) loop or NULL if outermost loop.  */
 359   struct loop *outer;
 360
 361   /* The first inner (child) loop or NULL if innermost loop.  */
 362   struct loop *inner;
 363
 364   /* Link to the next (sibling) loop.  */
 365   struct loop *next;
 366
 367   /* Non-zero if the loop shares a header with another loop.  */
 368   int shared;
 369
 370   /* Non-zero if the loop is invalid (e.g., contains setjmp.).  */
 371   int invalid;
 372
 373   /* Auxiliary info specific to a pass.  */
 374   void *aux;
 375
 376   /* The following are currently used by loop.c but they are likely to
 377      disappear as loop.c is converted to use the CFG.  */
 378
 379   /* Non-zero if the loop has a NOTE_INSN_LOOP_VTOP.  */
 380   rtx vtop;
 381
 382   /* Non-zero if the loop has a NOTE_INSN_LOOP_CONT.
 383      A continue statement will generate a branch to NEXT_INSN (cont).  */
 384   rtx cont;
 385
 386   /* The dominator of cont.  */
 387   rtx cont_dominator;
 388
 389   /* The NOTE_INSN_LOOP_BEG.  */
 390   rtx start;
 391
 392   /* The NOTE_INSN_LOOP_END.  */
 393   rtx end;
 394
 395   /* For a rotated loop that is entered near the bottom,
 396      this is the label at the top.  Otherwise it is zero.  */
 397   rtx top;
 398
 399   /* Place in the loop where control enters.  */
 400   rtx scan_start;
 401
 402   /* The position where to sink insns out of the loop.  */
 403   rtx sink;
 404
 405   /* List of all LABEL_REFs which refer to code labels outside the
 406      loop.  Used by routines that need to know all loop exits, such as
 407      final_biv_value and final_giv_value.
 408
 409      This does not include loop exits due to return instructions.
 410      This is because all bivs and givs are pseudos, and hence must be
 411      dead after a return, so the presense of a return does not affect
 412      any of the optimizations that use this info.  It is simpler to
 413      just not include return instructions on this list.  */
 414   rtx exit_labels;
 415
 416   /* The number of LABEL_REFs on exit_labels for this loop and all
 417      loops nested inside it.  */
 418   int exit_count;
 419 };
 420
 421
 422 /* Structure to hold CFG information about natural loops within a function.  */
 423 struct loops
 424 {
 425   /* Number of natural loops in the function.  */
 426   int num;
 427
 428   /* Maxium nested loop level in the function.  */
 429   int levels;
 430
 431   /* Array of natural loop descriptors (scanning this array in reverse order
 432      will find the inner loops before their enclosing outer loops).  */
 433   struct loop *array;
 434
 435   /* Pointer to root of loop heirachy tree.  */
 436   struct loop *tree;
 437
 438   /* Information derived from the CFG.  */
 439   struct cfg
 440   {
 441     /* The bitmap vector of dominators or NULL if not computed.  */
 442     sbitmap *dom;
 443
 444     /* The ordering of the basic blocks in a depth first search.  */
 445     int *dfs_order;
 446
 447     /* The reverse completion ordering of the basic blocks found in a
 448        depth first search.  */
 449     int *rc_order;
 450   } cfg;
 451
 452   /* Headers shared by multiple loops that should be merged.  */
 453   sbitmap shared_headers;
 454 };
 455
 456 extern int flow_loops_find PARAMS ((struct loops *, int flags));
 457 extern int flow_loops_update PARAMS ((struct loops *, int flags));
 458 extern void flow_loops_free PARAMS ((struct loops *));
 459 extern void flow_loops_dump PARAMS ((const struct loops *, FILE *,
 460                                      void (*)(const struct loop *,
 461                                               FILE *, int), int));
 462 extern void flow_loop_dump PARAMS ((const struct loop *, FILE *,
 463                                     void (*)(const struct loop *,
 464                                              FILE *, int), int));
 465 extern int flow_loop_scan PARAMS ((struct loops *, struct loop *, int));
 466
 467 /* This structure maintains an edge list vector.  */
 468 struct edge_list
 469 {
 470   int num_blocks;
 471   int num_edges;
 472   edge *index_to_edge;
 473 };
 474
 475 /* This is the value which indicates no edge is present.  */
 476 #define EDGE_INDEX_NO_EDGE      -1
 477
 478 /* EDGE_INDEX returns an integer index for an edge, or EDGE_INDEX_NO_EDGE
 479    if there is no edge between the 2 basic blocks.  */
 480 #define EDGE_INDEX(el, pred, succ) (find_edge_index ((el), (pred), (succ)))
 481
 482 /* INDEX_EDGE_PRED_BB and INDEX_EDGE_SUCC_BB return a pointer to the basic
 483    block which is either the pred or succ end of the indexed edge.  */
 484 #define INDEX_EDGE_PRED_BB(el, index)   ((el)->index_to_edge[(index)]->src)
 485 #define INDEX_EDGE_SUCC_BB(el, index)   ((el)->index_to_edge[(index)]->dest)
 486
 487 /* INDEX_EDGE returns a pointer to the edge.  */
 488 #define INDEX_EDGE(el, index)           ((el)->index_to_edge[(index)])
 489
 490 /* Number of edges in the compressed edge list.  */
 491 #define NUM_EDGES(el)                   ((el)->num_edges)
 492
 493 /* BB is assumed to contain conditional jump.  Return the fallthru edge.  */
 494 #define FALLTHRU_EDGE(bb)               ((bb)->succ->flags & EDGE_FALLTHRU \
 495                                          ? (bb)->succ : (bb)->succ->succ_next)
 496
 497 /* BB is assumed to contain conditional jump.  Return the branch edge.  */
 498 #define BRANCH_EDGE(bb)                 ((bb)->succ->flags & EDGE_FALLTHRU \
 499                                          ? (bb)->succ->succ_next : (bb)->succ)
 500
 501 struct edge_list * create_edge_list     PARAMS ((void));
 502 void free_edge_list                     PARAMS ((struct edge_list *));
 503 void print_edge_list                    PARAMS ((FILE *, struct edge_list *));
 504 void verify_edge_list                   PARAMS ((FILE *, struct edge_list *));
 505 int find_edge_index                     PARAMS ((struct edge_list *,
 506                                                  basic_block, basic_block));
 507
 508
 509 enum update_life_extent
 510 {
 511   UPDATE_LIFE_LOCAL = 0,
 512   UPDATE_LIFE_GLOBAL = 1,
 513   UPDATE_LIFE_GLOBAL_RM_NOTES = 2
 514 };
 515
 516 /* Flags for life_analysis and update_life_info.  */
 517
 518 #define PROP_DEATH_NOTES        1       /* Create DEAD and UNUSED notes.  */
 519 #define PROP_LOG_LINKS          2       /* Create LOG_LINKS.  */
 520 #define PROP_REG_INFO           4       /* Update regs_ever_live et al.  */
 521 #define PROP_KILL_DEAD_CODE     8       /* Remove dead code.  */
 522 #define PROP_SCAN_DEAD_CODE     16      /* Scan for dead code.  */
 523 #define PROP_AUTOINC            32      /* Create autoinc mem references.  */
 524 #define PROP_FINAL              63      /* All of the above.  */
 525
 526 /* Flags for loop discovery.  */
 527
 528 #define LOOP_TREE               1       /* Build loop hierarchy tree.  */
 529 #define LOOP_PRE_HEADER         2       /* Analyse loop pre-header.  */
 530 #define LOOP_ENTRY_EDGES        4       /* Find entry edges.  */
 531 #define LOOP_EXIT_EDGES         8       /* Find exit edges.  */
 532 #define LOOP_EDGES              (LOOP_ENTRY_EDGES | LOOP_EXIT_EDGES)
 533 #define LOOP_EXITS_DOMS        16       /* Find nodes that dom. all exits.  */
 534 #define LOOP_ALL               31       /* All of the above  */
 535
 536 extern void life_analysis       PARAMS ((rtx, FILE *, int));
 537 extern void update_life_info    PARAMS ((sbitmap, enum update_life_extent,
 538                                          int));
 539 extern int count_or_remove_death_notes  PARAMS ((sbitmap, int));
 540 extern void propagate_block     PARAMS ((basic_block, regset, regset, regset,
 541                                          int));
 542
 543 struct propagate_block_info;
 544 extern rtx propagate_one_insn   PARAMS ((struct propagate_block_info *, rtx));
 545 extern struct propagate_block_info *init_propagate_block_info
 546   PARAMS ((basic_block, regset, regset, regset, int));
 547 extern void free_propagate_block_info PARAMS ((struct propagate_block_info *));
 548
 549 /* In lcm.c */
 550 extern struct edge_list *pre_edge_lcm   PARAMS ((FILE *, int, sbitmap *,
 551                                                  sbitmap *, sbitmap *,
 552                                                  sbitmap *, sbitmap **,
 553                                                  sbitmap **));
 554 extern struct edge_list *pre_edge_rev_lcm PARAMS ((FILE *, int, sbitmap *,
 555                                                    sbitmap *, sbitmap *,
 556                                                    sbitmap *, sbitmap **,
 557                                                    sbitmap **));
 558 extern void compute_available           PARAMS ((sbitmap *, sbitmap *,
 559                                                  sbitmap *, sbitmap *));
 560 extern int optimize_mode_switching      PARAMS ((FILE *));
 561
 562 /* In emit-rtl.c.  */
 563 extern rtx emit_block_insn_after        PARAMS ((rtx, rtx, basic_block));
 564 extern rtx emit_block_insn_before       PARAMS ((rtx, rtx, basic_block));
 565
 566 /* In predict.c */
 567 extern void estimate_probability        PARAMS ((struct loops *));
 568 extern void expected_value_to_br_prob   PARAMS ((void));
 569
 570 /* In flow.c */
 571 extern void init_flow                   PARAMS ((void));
 572 extern void reorder_basic_blocks        PARAMS ((void));
 573 extern void dump_bb                     PARAMS ((basic_block, FILE *));
 574 extern void debug_bb                    PARAMS ((basic_block));
 575 extern void debug_bb_n                  PARAMS ((int));
 576 extern void dump_regset                 PARAMS ((regset, FILE *));
 577 extern void debug_regset                PARAMS ((regset));
 578 extern void allocate_reg_life_data      PARAMS ((void));
 579 extern void find_unreachable_blocks     PARAMS ((void));
 580
 581 /* This function is always defined so it can be called from the
 582    debugger, and it is declared extern so we don't get warnings about
 583    it being unused. */
 584 extern void verify_flow_info            PARAMS ((void));
 585 extern int flow_loop_outside_edge_p     PARAMS ((const struct loop *, edge));
 586
 587 typedef struct conflict_graph_def *conflict_graph;
 588
 589 /* Callback function when enumerating conflicts.  The arguments are
 590    the smaller and larger regno in the conflict.  Returns zero if
 591    enumeration is to continue, non-zero to halt enumeration.  */
 592 typedef int (*conflict_graph_enum_fn) PARAMS ((int, int, void *));
 593
 594
 595 /* Prototypes of operations on conflict graphs.  */
 596
 597 extern conflict_graph conflict_graph_new
 598                                         PARAMS ((int));
 599 extern void conflict_graph_delete       PARAMS ((conflict_graph));
 600 extern int conflict_graph_add           PARAMS ((conflict_graph,
 601                                                  int, int));
 602 extern int conflict_graph_conflict_p    PARAMS ((conflict_graph,
 603                                                  int, int));
 604 extern void conflict_graph_enum         PARAMS ((conflict_graph, int,
 605                                                  conflict_graph_enum_fn,
 606                                                  void *));
 607 extern void conflict_graph_merge_regs   PARAMS ((conflict_graph, int,
 608                                                  int));
 609 extern void conflict_graph_print        PARAMS ((conflict_graph, FILE*));
 610 extern conflict_graph conflict_graph_compute
 611                                         PARAMS ((regset,
 612                                                  partition));
 613
 614 /* In dominance.c */
 615
 616 enum cdi_direction
 617 {
 618   CDI_DOMINATORS,
 619   CDI_POST_DOMINATORS
 620 };
 621
 622 extern void calculate_dominance_info    PARAMS ((int *, sbitmap *,
 623                                                  enum cdi_direction));
 624
 625 #endif /* GCC_BASIC_BLOCK_H */