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 #ifndef TREE_CODE
  30 union tree_node;
  31 #define tree union tree_node *
  32 #endif
  33
  34 /* Head of register set linked list.  */
  35 typedef bitmap_head regset_head;
  36 /* A pointer to a regset_head.  */
  37 typedef bitmap regset;
  38
  39 /* Initialize a new regset.  */
  40 #define INIT_REG_SET(HEAD) bitmap_initialize (HEAD)
  41
  42 /* Clear a register set by freeing up the linked list.  */
  43 #define CLEAR_REG_SET(HEAD) bitmap_clear (HEAD)
  44
  45 /* Copy a register set to another register set.  */
  46 #define COPY_REG_SET(TO, FROM) bitmap_copy (TO, FROM)
  47
  48 /* Compare two register sets.  */
  49 #define REG_SET_EQUAL_P(A, B) bitmap_equal_p (A, B)
  50
  51 /* `and' a register set with a second register set.  */
  52 #define AND_REG_SET(TO, FROM) bitmap_operation (TO, TO, FROM, BITMAP_AND)
  53
  54 /* `and' the complement of a register set with a register set.  */
  55 #define AND_COMPL_REG_SET(TO, FROM) \
  56   bitmap_operation (TO, TO, FROM, BITMAP_AND_COMPL)
  57
  58 /* Inclusive or a register set with a second register set.  */
  59 #define IOR_REG_SET(TO, FROM) bitmap_operation (TO, TO, FROM, BITMAP_IOR)
  60
  61 /* Exclusive or a register set with a second register set.  */
  62 #define XOR_REG_SET(TO, FROM) bitmap_operation (TO, TO, FROM, BITMAP_XOR)
  63
  64 /* Or into TO the register set FROM1 `and'ed with the complement of FROM2.  */
  65 #define IOR_AND_COMPL_REG_SET(TO, FROM1, FROM2) \
  66   bitmap_ior_and_compl (TO, FROM1, FROM2)
  67
  68 /* Clear a single register in a register set.  */
  69 #define CLEAR_REGNO_REG_SET(HEAD, REG) bitmap_clear_bit (HEAD, REG)
  70
  71 /* Set a single register in a register set.  */
  72 #define SET_REGNO_REG_SET(HEAD, REG) bitmap_set_bit (HEAD, REG)
  73
  74 /* Return true if a register is set in a register set.  */
  75 #define REGNO_REG_SET_P(TO, REG) bitmap_bit_p (TO, REG)
  76
  77 /* Copy the hard registers in a register set to the hard register set.  */
  78 extern void reg_set_to_hard_reg_set PARAMS ((HARD_REG_SET *, bitmap));
  79 #define REG_SET_TO_HARD_REG_SET(TO, FROM)                               \
  80 do {                                                                    \
  81   CLEAR_HARD_REG_SET (TO);                                              \
  82   reg_set_to_hard_reg_set (&TO, FROM);                                  \
  83 } while (0)
  84
  85 /* Loop over all registers in REGSET, starting with MIN, setting REGNUM to the
  86    register number and executing CODE for all registers that are set. */
  87 #define EXECUTE_IF_SET_IN_REG_SET(REGSET, MIN, REGNUM, CODE)            \
  88   EXECUTE_IF_SET_IN_BITMAP (REGSET, MIN, REGNUM, CODE)
  89
  90 /* Loop over all registers in REGSET1 and REGSET2, starting with MIN, setting
  91    REGNUM to the register number and executing CODE for all registers that are
  92    set in the first regset and not set in the second. */
  93 #define EXECUTE_IF_AND_COMPL_IN_REG_SET(REGSET1, REGSET2, MIN, REGNUM, CODE) \
  94   EXECUTE_IF_AND_COMPL_IN_BITMAP (REGSET1, REGSET2, MIN, REGNUM, CODE)
  95
  96 /* Loop over all registers in REGSET1 and REGSET2, starting with MIN, setting
  97    REGNUM to the register number and executing CODE for all registers that are
  98    set in both regsets. */
  99 #define EXECUTE_IF_AND_IN_REG_SET(REGSET1, REGSET2, MIN, REGNUM, CODE) \
 100   EXECUTE_IF_AND_IN_BITMAP (REGSET1, REGSET2, MIN, REGNUM, CODE)
 101
 102 /* Allocate a register set with oballoc.  */
 103 #define OBSTACK_ALLOC_REG_SET(OBSTACK) BITMAP_OBSTACK_ALLOC (OBSTACK)
 104
 105 /* Initialize a register set.  Returns the new register set.  */
 106 #define INITIALIZE_REG_SET(HEAD) bitmap_initialize (&HEAD)
 107
 108 /* Do any cleanup needed on a regset when it is no longer used.  */
 109 #define FREE_REG_SET(REGSET) BITMAP_FREE(REGSET)
 110
 111 /* Do any one-time initializations needed for regsets.  */
 112 #define INIT_ONCE_REG_SET() BITMAP_INIT_ONCE ()
 113
 114 /* Grow any tables needed when the number of registers is calculated
 115    or extended.  For the linked list allocation, nothing needs to
 116    be done, other than zero the statistics on the first allocation.  */
 117 #define MAX_REGNO_REG_SET(NUM_REGS, NEW_P, RENUMBER_P)
 118
 119 /* Type we use to hold basic block counters.  Should be at least 64bit.  */
 120 typedef HOST_WIDEST_INT gcov_type;
 121
 122 /* Control flow edge information.  */
 123 typedef struct edge_def {
 124   /* Links through the predecessor and successor lists.  */
 125   struct edge_def *pred_next, *succ_next;
 126
 127   /* The two blocks at the ends of the edge.  */
 128   struct basic_block_def *src, *dest;
 129
 130   /* Instructions queued on the edge.  */
 131   rtx insns;
 132
 133   /* Auxiliary info specific to a pass.  */
 134   void *aux;
 135
 136   int flags;                    /* see EDGE_* below  */
 137   int probability;              /* biased by REG_BR_PROB_BASE */
 138   gcov_type count;              /* Expected number of executions calculated
 139                                    in profile.c  */
 140 } *edge;
 141
 142 #define EDGE_FALLTHRU           1
 143 #define EDGE_CRITICAL           2
 144 #define EDGE_ABNORMAL           4
 145 #define EDGE_ABNORMAL_CALL      8
 146 #define EDGE_EH                 16
 147 #define EDGE_FAKE               32
 148
 149 #define EDGE_COMPLEX    (EDGE_ABNORMAL | EDGE_ABNORMAL_CALL | EDGE_EH)
 150
 151
 152 /* A basic block is a sequence of instructions with only entry and
 153    only one exit.  If any one of the instructions are executed, they
 154    will all be executed, and in sequence from first to last.
 155
 156    There may be COND_EXEC instructions in the basic block.  The
 157    COND_EXEC *instructions* will be executed -- but if the condition
 158    is false the conditionally executed *expressions* will of course
 159    not be executed.  We don't consider the conditionally executed
 160    expression (which might have side-effects) to be in a separate
 161    basic block because the program counter will always be at the same
 162    location after the COND_EXEC instruction, regardless of whether the
 163    condition is true or not.
 164
 165    Basic blocks need not start with a label nor end with a jump insn.
 166    For example, a previous basic block may just "conditionally fall"
 167    into the succeeding basic block, and the last basic block need not
 168    end with a jump insn.  Block 0 is a descendant of the entry block.
 169
 170    A basic block beginning with two labels cannot have notes between
 171    the labels.
 172
 173    Data for jump tables are stored in jump_insns that occur in no
 174    basic block even though these insns can follow or precede insns in
 175    basic blocks.  */
 176
 177 /* Basic block information indexed by block number.  */
 178 typedef struct basic_block_def {
 179   /* The first and last insns of the block.  */
 180   rtx head, end;
 181
 182   /* The first and last trees of the block.  */
 183   tree head_tree;
 184   tree end_tree;
 185
 186   /* The edges into and out of the block.  */
 187   edge pred, succ;
 188
 189   /* Liveness info.  */
 190
 191   /* The registers that are modified within this in block.  */
 192   regset local_set;
 193   /* The registers that are conditionally modified within this block.
 194      In other words, registers that are set only as part of a
 195      COND_EXEC.  */
 196   regset cond_local_set;
 197   /* The registers that are live on entry to this block.
 198
 199      Note that in SSA form, global_live_at_start does not reflect the
 200      use of regs in phi functions, since the liveness of these regs
 201      may depend on which edge was taken into the block.  */
 202   regset global_live_at_start;
 203   /* The registers that are live on exit from this block.  */
 204   regset global_live_at_end;
 205
 206   /* Auxiliary info specific to a pass.  */
 207   void *aux;
 208
 209   /* The index of this block.  */
 210   int index;
 211
 212   /* The loop depth of this block.  */
 213   int loop_depth;
 214
 215   /* Expected number of executions: calculated in profile.c.  */
 216   gcov_type count;
 217
 218   /* Expected frequency.  Normalized to be in range 0 to BB_FREQ_MAX.  */
 219   int frequency;
 220 } *basic_block;
 221
 222 #define BB_FREQ_MAX 10000
 223
 224 /* Number of basic blocks in the current function.  */
 225
 226 extern int n_basic_blocks;
 227
 228 /* Number of edges in the current function.  */
 229
 230 extern int n_edges;
 231
 232 /* Index by basic block number, get basic block struct info.  */
 233
 234 extern varray_type basic_block_info;
 235
 236 #define BASIC_BLOCK(N)  (VARRAY_BB (basic_block_info, (N)))
 237
 238 /* What registers are live at the setjmp call.  */
 239
 240 extern regset regs_live_at_setjmp;
 241
 242 /* Indexed by n, gives number of basic block that  (REG n) is used in.
 243    If the value is REG_BLOCK_GLOBAL (-2),
 244    it means (REG n) is used in more than one basic block.
 245    REG_BLOCK_UNKNOWN (-1) means it hasn't been seen yet so we don't know.
 246    This information remains valid for the rest of the compilation
 247    of the current function; it is used to control register allocation.  */
 248
 249 #define REG_BLOCK_UNKNOWN -1
 250 #define REG_BLOCK_GLOBAL -2
 251
 252 #define REG_BASIC_BLOCK(N) (VARRAY_REG (reg_n_info, N)->basic_block)
 253 \f
 254 /* Stuff for recording basic block info.  */
 255
 256 #define BLOCK_HEAD(B)      (BASIC_BLOCK (B)->head)
 257 #define BLOCK_END(B)       (BASIC_BLOCK (B)->end)
 258
 259 #define BLOCK_HEAD_TREE(B) (BASIC_BLOCK (B)->head_tree)
 260 #define BLOCK_END_TREE(B) (BASIC_BLOCK (B)->end_tree)
 261
 262 /* Special block numbers [markers] for entry and exit.  */
 263 #define ENTRY_BLOCK (-1)
 264 #define EXIT_BLOCK (-2)
 265
 266 /* Special block number not valid for any block. */
 267 #define INVALID_BLOCK (-3)
 268
 269 /* Similarly, block pointers for the edge list.  */
 270 extern struct basic_block_def entry_exit_blocks[2];
 271 #define ENTRY_BLOCK_PTR (&entry_exit_blocks[0])
 272 #define EXIT_BLOCK_PTR  (&entry_exit_blocks[1])
 273
 274 extern varray_type basic_block_for_insn;
 275 #define BLOCK_FOR_INSN(INSN)  VARRAY_BB (basic_block_for_insn, INSN_UID (INSN))
 276 #define BLOCK_NUM(INSN)       (BLOCK_FOR_INSN (INSN)->index + 0)
 277
 278 extern void compute_bb_for_insn         PARAMS ((int));
 279 extern void update_bb_for_insn          PARAMS ((basic_block));
 280 extern void set_block_for_insn          PARAMS ((rtx, basic_block));
 281 extern void set_block_for_new_insns     PARAMS ((rtx, basic_block));
 282
 283 extern void free_basic_block_vars       PARAMS ((int));
 284
 285 extern edge split_block                 PARAMS ((basic_block, rtx));
 286 extern basic_block split_edge           PARAMS ((edge));
 287 extern void insert_insn_on_edge         PARAMS ((rtx, edge));
 288 extern void commit_edge_insertions      PARAMS ((void));
 289 extern void remove_fake_edges           PARAMS ((void));
 290 extern void add_noreturn_fake_exit_edges        PARAMS ((void));
 291 extern void connect_infinite_loops_to_exit      PARAMS ((void));
 292 extern int flow_call_edges_add          PARAMS ((sbitmap));
 293 extern rtx flow_delete_insn             PARAMS ((rtx));
 294 extern void flow_delete_insn_chain      PARAMS ((rtx, rtx));
 295 extern void make_edge                   PARAMS ((sbitmap *, basic_block,
 296                                                  basic_block, int));
 297 extern void remove_edge                 PARAMS ((edge));
 298 extern void redirect_edge_succ          PARAMS ((edge, basic_block));
 299 extern void redirect_edge_pred          PARAMS ((edge, basic_block));
 300 extern void create_basic_block          PARAMS ((int, rtx, rtx, rtx));
 301 extern int flow_delete_block            PARAMS ((basic_block));
 302 extern void merge_blocks_nomove         PARAMS ((basic_block, basic_block));
 303 extern void tidy_fallthru_edge          PARAMS ((edge, basic_block,
 304                                                  basic_block));
 305 extern int flow_depth_first_order_compute       PARAMS ((int *, int *));
 306 extern void dump_edge_info              PARAMS ((FILE *, edge, int));
 307 extern void clear_edges                 PARAMS ((void));
 308 extern void mark_critical_edges         PARAMS ((void));
 309 extern rtx first_insn_after_basic_block_note    PARAMS ((basic_block));
 310
 311 /* Structure to hold information for each natural loop.  */
 312 struct loop
 313 {
 314   /* Index into loops array.  */
 315   int num;
 316
 317   /* Basic block of loop header.  */
 318   basic_block header;
 319
 320   /* Basic block of loop latch.  */
 321   basic_block latch;
 322
 323   /* Basic block of loop pre-header or NULL if it does not exist.  */
 324   basic_block pre_header;
 325
 326   /* Array of edges along the pre-header extended basic block trace.
 327      The source of the first edge is the root node of pre-header
 328      extended basic block, if it exists.  */
 329   edge *pre_header_edges;
 330
 331   /* Number of edges along the pre_header extended basic block trace.  */
 332   int num_pre_header_edges;
 333
 334   /* The first block in the loop.  This is not necessarily the same as
 335      the loop header.  */
 336   basic_block first;
 337
 338   /* The last block in the loop.  This is not necessarily the same as
 339      the loop latch.  */
 340   basic_block last;
 341
 342   /* Bitmap of blocks contained within the loop.  */
 343   sbitmap nodes;
 344
 345   /* Number of blocks contained within the loop.  */
 346   int num_nodes;
 347
 348   /* Array of edges that enter the loop.  */
 349   edge *entry_edges;
 350
 351   /* Number of edges that enter the loop.  */
 352   int num_entries;
 353
 354   /* Array of edges that exit the loop.  */
 355   edge *exit_edges;
 356
 357   /* Number of edges that exit the loop.  */
 358   int num_exits;
 359
 360   /* Bitmap of blocks that dominate all exits of the loop.  */
 361   sbitmap exits_doms;
 362
 363   /* The loop nesting depth.  */
 364   int depth;
 365
 366   /* The height of the loop (enclosed loop levels) within the loop
 367      hierarchy tree.  */
 368   int level;
 369
 370   /* The outer (parent) loop or NULL if outermost loop.  */
 371   struct loop *outer;
 372
 373   /* The first inner (child) loop or NULL if innermost loop.  */
 374   struct loop *inner;
 375
 376   /* Link to the next (sibling) loop.  */
 377   struct loop *next;
 378
 379   /* Non-zero if the loop shares a header with another loop.  */
 380   int shared;
 381
 382   /* Non-zero if the loop is invalid (e.g., contains setjmp.).  */
 383   int invalid;
 384
 385   /* Auxiliary info specific to a pass.  */
 386   void *aux;
 387
 388   /* The following are currently used by loop.c but they are likely to
 389      disappear as loop.c is converted to use the CFG.  */
 390
 391   /* Non-zero if the loop has a NOTE_INSN_LOOP_VTOP.  */
 392   rtx vtop;
 393
 394   /* Non-zero if the loop has a NOTE_INSN_LOOP_CONT.
 395      A continue statement will generate a branch to NEXT_INSN (cont).  */
 396   rtx cont;
 397
 398   /* The dominator of cont.  */
 399   rtx cont_dominator;
 400
 401   /* The NOTE_INSN_LOOP_BEG.  */
 402   rtx start;
 403
 404   /* The NOTE_INSN_LOOP_END.  */
 405   rtx end;
 406
 407   /* For a rotated loop that is entered near the bottom,
 408      this is the label at the top.  Otherwise it is zero.  */
 409   rtx top;
 410
 411   /* Place in the loop where control enters.  */
 412   rtx scan_start;
 413
 414   /* The position where to sink insns out of the loop.  */
 415   rtx sink;
 416
 417   /* List of all LABEL_REFs which refer to code labels outside the
 418      loop.  Used by routines that need to know all loop exits, such as
 419      final_biv_value and final_giv_value.
 420
 421      This does not include loop exits due to return instructions.
 422      This is because all bivs and givs are pseudos, and hence must be
 423      dead after a return, so the presense of a return does not affect
 424      any of the optimizations that use this info.  It is simpler to
 425      just not include return instructions on this list.  */
 426   rtx exit_labels;
 427
 428   /* The number of LABEL_REFs on exit_labels for this loop and all
 429      loops nested inside it.  */
 430   int exit_count;
 431 };
 432
 433
 434 /* Structure to hold CFG information about natural loops within a function.  */
 435 struct loops
 436 {
 437   /* Number of natural loops in the function.  */
 438   int num;
 439
 440   /* Maxium nested loop level in the function.  */
 441   int levels;
 442
 443   /* Array of natural loop descriptors (scanning this array in reverse order
 444      will find the inner loops before their enclosing outer loops).  */
 445   struct loop *array;
 446
 447   /* Pointer to root of loop heirachy tree.  */
 448   struct loop *tree_root;
 449
 450   /* Information derived from the CFG.  */
 451   struct cfg
 452   {
 453     /* The bitmap vector of dominators or NULL if not computed.  */
 454     sbitmap *dom;
 455
 456     /* The ordering of the basic blocks in a depth first search.  */
 457     int *dfs_order;
 458
 459     /* The reverse completion ordering of the basic blocks found in a
 460        depth first search.  */
 461     int *rc_order;
 462   } cfg;
 463
 464   /* Headers shared by multiple loops that should be merged.  */
 465   sbitmap shared_headers;
 466 };
 467
 468 extern int flow_loops_find PARAMS ((struct loops *, int flags));
 469 extern int flow_loops_update PARAMS ((struct loops *, int flags));
 470 extern void flow_loops_free PARAMS ((struct loops *));
 471 extern void flow_loops_dump PARAMS ((const struct loops *, FILE *,
 472                                      void (*)(const struct loop *,
 473                                               FILE *, int), int));
 474 extern void flow_loop_dump PARAMS ((const struct loop *, FILE *,
 475                                     void (*)(const struct loop *,
 476                                              FILE *, int), int));
 477 extern int flow_loop_scan PARAMS ((struct loops *, struct loop *, int));
 478
 479 /* This structure maintains an edge list vector.  */
 480 struct edge_list
 481 {
 482   int num_blocks;
 483   int num_edges;
 484   edge *index_to_edge;
 485 };
 486
 487 /* This is the value which indicates no edge is present.  */
 488 #define EDGE_INDEX_NO_EDGE      -1
 489
 490 /* EDGE_INDEX returns an integer index for an edge, or EDGE_INDEX_NO_EDGE
 491    if there is no edge between the 2 basic blocks.  */
 492 #define EDGE_INDEX(el, pred, succ) (find_edge_index ((el), (pred), (succ)))
 493
 494 /* INDEX_EDGE_PRED_BB and INDEX_EDGE_SUCC_BB return a pointer to the basic
 495    block which is either the pred or succ end of the indexed edge.  */
 496 #define INDEX_EDGE_PRED_BB(el, index)   ((el)->index_to_edge[(index)]->src)
 497 #define INDEX_EDGE_SUCC_BB(el, index)   ((el)->index_to_edge[(index)]->dest)
 498
 499 /* INDEX_EDGE returns a pointer to the edge.  */
 500 #define INDEX_EDGE(el, index)           ((el)->index_to_edge[(index)])
 501
 502 /* Number of edges in the compressed edge list.  */
 503 #define NUM_EDGES(el)                   ((el)->num_edges)
 504
 505 /* BB is assumed to contain conditional jump.  Return the fallthru edge.  */
 506 #define FALLTHRU_EDGE(bb)               ((bb)->succ->flags & EDGE_FALLTHRU \
 507                                          ? (bb)->succ : (bb)->succ->succ_next)
 508
 509 /* BB is assumed to contain conditional jump.  Return the branch edge.  */
 510 #define BRANCH_EDGE(bb)                 ((bb)->succ->flags & EDGE_FALLTHRU \
 511                                          ? (bb)->succ->succ_next : (bb)->succ)
 512
 513 struct edge_list * create_edge_list     PARAMS ((void));
 514 void free_edge_list                     PARAMS ((struct edge_list *));
 515 void print_edge_list                    PARAMS ((FILE *, struct edge_list *));
 516 void verify_edge_list                   PARAMS ((FILE *, struct edge_list *));
 517 int find_edge_index                     PARAMS ((struct edge_list *,
 518                                                  basic_block, basic_block));
 519
 520
 521 enum update_life_extent
 522 {
 523   UPDATE_LIFE_LOCAL = 0,
 524   UPDATE_LIFE_GLOBAL = 1,
 525   UPDATE_LIFE_GLOBAL_RM_NOTES = 2
 526 };
 527
 528 /* Flags for life_analysis and update_life_info.  */
 529
 530 #define PROP_DEATH_NOTES        1       /* Create DEAD and UNUSED notes.  */
 531 #define PROP_LOG_LINKS          2       /* Create LOG_LINKS.  */
 532 #define PROP_REG_INFO           4       /* Update regs_ever_live et al.  */
 533 #define PROP_KILL_DEAD_CODE     8       /* Remove dead code.  */
 534 #define PROP_SCAN_DEAD_CODE     16      /* Scan for dead code.  */
 535 #define PROP_AUTOINC            32      /* Create autoinc mem references.  */
 536 #define PROP_FINAL              63      /* All of the above.  */
 537
 538 #define CLEANUP_EXPENSIVE       1       /* Do relativly expensive optimizations
 539                                            except for edge forwarding */
 540 #define CLEANUP_CROSSJUMP       2       /* Do crossjumping.  */
 541 #define CLEANUP_POST_REGSTACK   4       /* We run after reg-stack and need
 542                                            to care REG_DEAD notes.  */
 543 /* Flags for loop discovery.  */
 544
 545 #define LOOP_TREE               1       /* Build loop hierarchy tree.  */
 546 #define LOOP_PRE_HEADER         2       /* Analyse loop pre-header.  */
 547 #define LOOP_ENTRY_EDGES        4       /* Find entry edges.  */
 548 #define LOOP_EXIT_EDGES         8       /* Find exit edges.  */
 549 #define LOOP_EDGES              (LOOP_ENTRY_EDGES | LOOP_EXIT_EDGES)
 550 #define LOOP_EXITS_DOMS        16       /* Find nodes that dom. all exits.  */
 551 #define LOOP_ALL               31       /* All of the above  */
 552
 553 extern void life_analysis       PARAMS ((rtx, FILE *, int));
 554 extern void update_life_info    PARAMS ((sbitmap, enum update_life_extent,
 555                                          int));
 556 extern int count_or_remove_death_notes  PARAMS ((sbitmap, int));
 557 extern void propagate_block     PARAMS ((basic_block, regset, regset, regset,
 558                                          int));
 559
 560 struct propagate_block_info;
 561 extern rtx propagate_one_insn   PARAMS ((struct propagate_block_info *, rtx));
 562 extern struct propagate_block_info *init_propagate_block_info
 563   PARAMS ((basic_block, regset, regset, regset, int));
 564 extern void free_propagate_block_info PARAMS ((struct propagate_block_info *));
 565
 566 /* In lcm.c */
 567 extern struct edge_list *pre_edge_lcm   PARAMS ((FILE *, int, sbitmap *,
 568                                                  sbitmap *, sbitmap *,
 569                                                  sbitmap *, sbitmap **,
 570                                                  sbitmap **));
 571 extern struct edge_list *pre_edge_rev_lcm PARAMS ((FILE *, int, sbitmap *,
 572                                                    sbitmap *, sbitmap *,
 573                                                    sbitmap *, sbitmap **,
 574                                                    sbitmap **));
 575 extern void compute_available           PARAMS ((sbitmap *, sbitmap *,
 576                                                  sbitmap *, sbitmap *));
 577 extern int optimize_mode_switching      PARAMS ((FILE *));
 578
 579 /* In emit-rtl.c.  */
 580 extern rtx emit_block_insn_after        PARAMS ((rtx, rtx, basic_block));
 581 extern rtx emit_block_insn_before       PARAMS ((rtx, rtx, basic_block));
 582
 583 /* In predict.c */
 584 extern void estimate_probability        PARAMS ((struct loops *));
 585 extern void expected_value_to_br_prob   PARAMS ((void));
 586
 587 /* In flow.c */
 588 extern void init_flow                   PARAMS ((void));
 589 extern void reorder_basic_blocks        PARAMS ((void));
 590 extern void dump_bb                     PARAMS ((basic_block, FILE *));
 591 extern void debug_bb                    PARAMS ((basic_block));
 592 extern void debug_bb_n                  PARAMS ((int));
 593 extern void dump_regset                 PARAMS ((regset, FILE *));
 594 extern void debug_regset                PARAMS ((regset));
 595 extern void allocate_reg_life_data      PARAMS ((void));
 596 extern void allocate_bb_life_data       PARAMS ((void));
 597 extern void find_unreachable_blocks     PARAMS ((void));
 598
 599 /* This function is always defined so it can be called from the
 600    debugger, and it is declared extern so we don't get warnings about
 601    it being unused. */
 602 extern void verify_flow_info            PARAMS ((void));
 603 extern int flow_loop_outside_edge_p     PARAMS ((const struct loop *, edge));
 604
 605 typedef struct conflict_graph_def *conflict_graph;
 606
 607 /* Callback function when enumerating conflicts.  The arguments are
 608    the smaller and larger regno in the conflict.  Returns zero if
 609    enumeration is to continue, non-zero to halt enumeration.  */
 610 typedef int (*conflict_graph_enum_fn) PARAMS ((int, int, void *));
 611
 612
 613 /* Prototypes of operations on conflict graphs.  */
 614
 615 extern conflict_graph conflict_graph_new
 616                                         PARAMS ((int));
 617 extern void conflict_graph_delete       PARAMS ((conflict_graph));
 618 extern int conflict_graph_add           PARAMS ((conflict_graph,
 619                                                  int, int));
 620 extern int conflict_graph_conflict_p    PARAMS ((conflict_graph,
 621                                                  int, int));
 622 extern void conflict_graph_enum         PARAMS ((conflict_graph, int,
 623                                                  conflict_graph_enum_fn,
 624                                                  void *));
 625 extern void conflict_graph_merge_regs   PARAMS ((conflict_graph, int,
 626                                                  int));
 627 extern void conflict_graph_print        PARAMS ((conflict_graph, FILE*));
 628 extern conflict_graph conflict_graph_compute
 629                                         PARAMS ((regset,
 630                                                  partition));
 631
 632 /* In dominance.c */
 633
 634 enum cdi_direction
 635 {
 636   CDI_DOMINATORS,
 637   CDI_POST_DOMINATORS
 638 };
 639
 640 extern void calculate_dominance_info    PARAMS ((int *, sbitmap *,
 641                                                  enum cdi_direction));
 642
 643 #endif /* GCC_BASIC_BLOCK_H */