gcc/basic-block.h

   1 /* Define control and data flow tables, and regsets.
   2    Copyright (C) 1987, 1997, 1998, 1999, 2000, 2001, 2002, 2003
   3    Free Software Foundation, Inc.
   4
   5 This file is part of GCC.
   6
   7 GCC is free software; you can redistribute it and/or modify it under
   8 the terms of the GNU General Public License as published by the Free
   9 Software Foundation; either version 2, or (at your option) any later
  10 version.
  11
  12 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
  13 WARRANTY; without even the implied warranty of MERCHANTABILITY or
  14 FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  15 for more details.
  16
  17 You should have received a copy of the GNU General Public License
  18 along with GCC; see the file COPYING.  If not, write to the Free
  19 Software Foundation, 59 Temple Place - Suite 330, Boston, MA
  20 02111-1307, USA.  */
  21
  22 #ifndef GCC_BASIC_BLOCK_H
  23 #define GCC_BASIC_BLOCK_H
  24
  25 #include "bitmap.h"
  26 #include "sbitmap.h"
  27 #include "varray.h"
  28 #include "partition.h"
  29 #include "hard-reg-set.h"
  30
  31 /* Head of register set linked list.  */
  32 typedef bitmap_head regset_head;
  33 /* A pointer to a regset_head.  */
  34 typedef bitmap regset;
  35
  36 /* Initialize a new regset.  */
  37 #define INIT_REG_SET(HEAD) bitmap_initialize (HEAD, 1)
  38
  39 /* Clear a register set by freeing up the linked list.  */
  40 #define CLEAR_REG_SET(HEAD) bitmap_clear (HEAD)
  41
  42 /* Copy a register set to another register set.  */
  43 #define COPY_REG_SET(TO, FROM) bitmap_copy (TO, FROM)
  44
  45 /* Compare two register sets.  */
  46 #define REG_SET_EQUAL_P(A, B) bitmap_equal_p (A, B)
  47
  48 /* `and' a register set with a second register set.  */
  49 #define AND_REG_SET(TO, FROM) bitmap_operation (TO, TO, FROM, BITMAP_AND)
  50
  51 /* `and' the complement of a register set with a register set.  */
  52 #define AND_COMPL_REG_SET(TO, FROM) \
  53   bitmap_operation (TO, TO, FROM, BITMAP_AND_COMPL)
  54
  55 /* Inclusive or a register set with a second register set.  */
  56 #define IOR_REG_SET(TO, FROM) bitmap_operation (TO, TO, FROM, BITMAP_IOR)
  57
  58 /* Exclusive or a register set with a second register set.  */
  59 #define XOR_REG_SET(TO, FROM) bitmap_operation (TO, TO, FROM, BITMAP_XOR)
  60
  61 /* Or into TO the register set FROM1 `and'ed with the complement of FROM2.  */
  62 #define IOR_AND_COMPL_REG_SET(TO, FROM1, FROM2) \
  63   bitmap_ior_and_compl (TO, FROM1, FROM2)
  64
  65 /* Clear a single register in a register set.  */
  66 #define CLEAR_REGNO_REG_SET(HEAD, REG) bitmap_clear_bit (HEAD, REG)
  67
  68 /* Set a single register in a register set.  */
  69 #define SET_REGNO_REG_SET(HEAD, REG) bitmap_set_bit (HEAD, REG)
  70
  71 /* Return true if a register is set in a register set.  */
  72 #define REGNO_REG_SET_P(TO, REG) bitmap_bit_p (TO, REG)
  73
  74 /* Copy the hard registers in a register set to the hard register set.  */
  75 extern void reg_set_to_hard_reg_set (HARD_REG_SET *, bitmap);
  76 #define REG_SET_TO_HARD_REG_SET(TO, FROM)                               \
  77 do {                                                                    \
  78   CLEAR_HARD_REG_SET (TO);                                              \
  79   reg_set_to_hard_reg_set (&TO, FROM);                                  \
  80 } while (0)
  81
  82 /* Loop over all registers in REGSET, starting with MIN, setting REGNUM to the
  83    register number and executing CODE for all registers that are set.  */
  84 #define EXECUTE_IF_SET_IN_REG_SET(REGSET, MIN, REGNUM, CODE)            \
  85   EXECUTE_IF_SET_IN_BITMAP (REGSET, MIN, REGNUM, CODE)
  86
  87 /* Loop over all registers in REGSET1 and REGSET2, starting with MIN, setting
  88    REGNUM to the register number and executing CODE for all registers that are
  89    set in the first regset and not set in the second.  */
  90 #define EXECUTE_IF_AND_COMPL_IN_REG_SET(REGSET1, REGSET2, MIN, REGNUM, CODE) \
  91   EXECUTE_IF_AND_COMPL_IN_BITMAP (REGSET1, REGSET2, MIN, REGNUM, CODE)
  92
  93 /* Loop over all registers in REGSET1 and REGSET2, starting with MIN, setting
  94    REGNUM to the register number and executing CODE for all registers that are
  95    set in both regsets.  */
  96 #define EXECUTE_IF_AND_IN_REG_SET(REGSET1, REGSET2, MIN, REGNUM, CODE) \
  97   EXECUTE_IF_AND_IN_BITMAP (REGSET1, REGSET2, MIN, REGNUM, CODE)
  98
  99 /* Allocate a register set with oballoc.  */
 100 #define OBSTACK_ALLOC_REG_SET(OBSTACK) BITMAP_OBSTACK_ALLOC (OBSTACK)
 101
 102 /* Initialize a register set.  Returns the new register set.  */
 103 #define INITIALIZE_REG_SET(HEAD) bitmap_initialize (&HEAD, 1)
 104
 105 /* Do any cleanup needed on a regset when it is no longer used.  */
 106 #define FREE_REG_SET(REGSET) BITMAP_FREE(REGSET)
 107
 108 /* Do any one-time initializations needed for regsets.  */
 109 #define INIT_ONCE_REG_SET() BITMAP_INIT_ONCE ()
 110
 111 /* Grow any tables needed when the number of registers is calculated
 112    or extended.  For the linked list allocation, nothing needs to
 113    be done, other than zero the statistics on the first allocation.  */
 114 #define MAX_REGNO_REG_SET(NUM_REGS, NEW_P, RENUMBER_P)
 115
 116 /* Type we use to hold basic block counters.  Should be at least
 117    64bit.  Although a counter cannot be negative, we use a signed
 118    type, because erroneous negative counts can be generated when the
 119    flow graph is manipulated by various optimizations.  A signed type
 120    makes those easy to detect.  */
 121 typedef HOST_WIDEST_INT gcov_type;
 122
 123 /* Control flow edge information.  */
 124 typedef struct edge_def {
 125   /* Links through the predecessor and successor lists.  */
 126   struct edge_def *pred_next, *succ_next;
 127
 128   /* The two blocks at the ends of the edge.  */
 129   struct basic_block_def *src, *dest;
 130
 131   /* Instructions queued on the edge.  */
 132   rtx insns;
 133
 134   /* Auxiliary info specific to a pass.  */
 135   void *aux;
 136
 137   int flags;                    /* see EDGE_* below  */
 138   int probability;              /* biased by REG_BR_PROB_BASE */
 139   gcov_type count;              /* Expected number of executions calculated
 140                                    in profile.c  */
 141 } *edge;
 142
 143 #define EDGE_FALLTHRU           1       /* 'Straight line' flow */
 144 #define EDGE_ABNORMAL           2       /* Strange flow, like computed
 145                                            label, or eh */
 146 #define EDGE_ABNORMAL_CALL      4       /* Call with abnormal exit
 147                                            like an exception, or sibcall */
 148 #define EDGE_EH                 8       /* Exception throw */
 149 #define EDGE_FAKE               16      /* Not a real edge (profile.c) */
 150 #define EDGE_DFS_BACK           32      /* A backwards edge */
 151 #define EDGE_CAN_FALLTHRU       64      /* Candidate for straight line
 152                                            flow.  */
 153 #define EDGE_IRREDUCIBLE_LOOP   128     /* Part of irreducible loop.  */
 154 #define EDGE_SIBCALL            256     /* Edge from sibcall to exit.  */
 155 #define EDGE_ALL_FLAGS          511
 156
 157 #define EDGE_COMPLEX    (EDGE_ABNORMAL | EDGE_ABNORMAL_CALL | EDGE_EH)
 158
 159 /* Counter summary from the last set of coverage counts read by
 160    profile.c.  */
 161 extern const struct gcov_ctr_summary *profile_info;
 162
 163 /* Declared in cfgloop.h.  */
 164 struct loop;
 165 struct loops;
 166
 167 /* A basic block is a sequence of instructions with only entry and
 168    only one exit.  If any one of the instructions are executed, they
 169    will all be executed, and in sequence from first to last.
 170
 171    There may be COND_EXEC instructions in the basic block.  The
 172    COND_EXEC *instructions* will be executed -- but if the condition
 173    is false the conditionally executed *expressions* will of course
 174    not be executed.  We don't consider the conditionally executed
 175    expression (which might have side-effects) to be in a separate
 176    basic block because the program counter will always be at the same
 177    location after the COND_EXEC instruction, regardless of whether the
 178    condition is true or not.
 179
 180    Basic blocks need not start with a label nor end with a jump insn.
 181    For example, a previous basic block may just "conditionally fall"
 182    into the succeeding basic block, and the last basic block need not
 183    end with a jump insn.  Block 0 is a descendant of the entry block.
 184
 185    A basic block beginning with two labels cannot have notes between
 186    the labels.
 187
 188    Data for jump tables are stored in jump_insns that occur in no
 189    basic block even though these insns can follow or precede insns in
 190    basic blocks.  */
 191
 192 /* Basic block information indexed by block number.  */
 193 typedef struct basic_block_def {
 194   /* The first and last insns of the block.  */
 195   rtx head, end;
 196
 197   /* The first and last trees of the block.  */
 198   tree head_tree;
 199   tree end_tree;
 200
 201   /* The edges into and out of the block.  */
 202   edge pred, succ;
 203
 204   /* Liveness info.  */
 205
 206   /* The registers that are modified within this in block.  */
 207   regset local_set;
 208   /* The registers that are conditionally modified within this block.
 209      In other words, registers that are set only as part of a
 210      COND_EXEC.  */
 211   regset cond_local_set;
 212   /* The registers that are live on entry to this block.
 213
 214      Note that in SSA form, global_live_at_start does not reflect the
 215      use of regs in phi functions, since the liveness of these regs
 216      may depend on which edge was taken into the block.  */
 217   regset global_live_at_start;
 218   /* The registers that are live on exit from this block.  */
 219   regset global_live_at_end;
 220
 221   /* Auxiliary info specific to a pass.  */
 222   void *aux;
 223
 224   /* The index of this block.  */
 225   int index;
 226
 227   /* Previous and next blocks in the chain.  */
 228   struct basic_block_def *prev_bb, *next_bb;
 229
 230   /* The loop depth of this block.  */
 231   int loop_depth;
 232
 233   /* Outermost loop containing the block.  */
 234   struct loop *loop_father;
 235
 236   /* Expected number of executions: calculated in profile.c.  */
 237   gcov_type count;
 238
 239   /* Expected frequency.  Normalized to be in range 0 to BB_FREQ_MAX.  */
 240   int frequency;
 241
 242   /* Various flags.  See BB_* below.  */
 243   int flags;
 244
 245   /* Additional data maintained by cfg_layout routines.  */
 246   struct reorder_block_def *rbi;
 247 } *basic_block;
 248
 249 #define BB_FREQ_MAX 10000
 250
 251 /* Masks for basic_block.flags.  */
 252 #define BB_DIRTY                1
 253 #define BB_NEW                  2
 254 #define BB_REACHABLE            4
 255 #define BB_VISITED              8
 256 #define BB_IRREDUCIBLE_LOOP     16
 257 #define BB_SUPERBLOCK           32
 258
 259 /* Number of basic blocks in the current function.  */
 260
 261 extern int n_basic_blocks;
 262
 263 /* First free basic block number.  */
 264
 265 extern int last_basic_block;
 266
 267 /* Number of edges in the current function.  */
 268
 269 extern int n_edges;
 270
 271 /* Index by basic block number, get basic block struct info.  */
 272
 273 extern varray_type basic_block_info;
 274
 275 #define BASIC_BLOCK(N)  (VARRAY_BB (basic_block_info, (N)))
 276
 277 /* For iterating over basic blocks.  */
 278 #define FOR_BB_BETWEEN(BB, FROM, TO, DIR) \
 279   for (BB = FROM; BB != TO; BB = BB->DIR)
 280
 281 #define FOR_EACH_BB(BB) \
 282   FOR_BB_BETWEEN (BB, ENTRY_BLOCK_PTR->next_bb, EXIT_BLOCK_PTR, next_bb)
 283
 284 #define FOR_EACH_BB_REVERSE(BB) \
 285   FOR_BB_BETWEEN (BB, EXIT_BLOCK_PTR->prev_bb, ENTRY_BLOCK_PTR, prev_bb)
 286
 287 /* Cycles through _all_ basic blocks, even the fake ones (entry and
 288    exit block).  */
 289
 290 #define FOR_ALL_BB(BB) \
 291   for (BB = ENTRY_BLOCK_PTR; BB; BB = BB->next_bb)
 292
 293 /* What registers are live at the setjmp call.  */
 294
 295 extern regset regs_live_at_setjmp;
 296
 297 /* Special labels found during CFG build.  */
 298
 299 extern GTY(()) rtx label_value_list;
 300 extern GTY(()) rtx tail_recursion_label_list;
 301
 302 extern struct obstack flow_obstack;
 303
 304 /* Indexed by n, gives number of basic block that  (REG n) is used in.
 305    If the value is REG_BLOCK_GLOBAL (-2),
 306    it means (REG n) is used in more than one basic block.
 307    REG_BLOCK_UNKNOWN (-1) means it hasn't been seen yet so we don't know.
 308    This information remains valid for the rest of the compilation
 309    of the current function; it is used to control register allocation.  */
 310
 311 #define REG_BLOCK_UNKNOWN -1
 312 #define REG_BLOCK_GLOBAL -2
 313
 314 #define REG_BASIC_BLOCK(N) (VARRAY_REG (reg_n_info, N)->basic_block)
 315 \f
 316 /* Stuff for recording basic block info.  */
 317
 318 #define BLOCK_HEAD(B)      (BASIC_BLOCK (B)->head)
 319 #define BLOCK_END(B)       (BASIC_BLOCK (B)->end)
 320
 321 #define BLOCK_HEAD_TREE(B) (BASIC_BLOCK (B)->head_tree)
 322 #define BLOCK_END_TREE(B) (BASIC_BLOCK (B)->end_tree)
 323
 324 /* Special block numbers [markers] for entry and exit.  */
 325 #define ENTRY_BLOCK (-1)
 326 #define EXIT_BLOCK (-2)
 327
 328 /* Special block number not valid for any block.  */
 329 #define INVALID_BLOCK (-3)
 330
 331 /* Similarly, block pointers for the edge list.  */
 332 extern struct basic_block_def entry_exit_blocks[2];
 333 #define ENTRY_BLOCK_PTR (&entry_exit_blocks[0])
 334 #define EXIT_BLOCK_PTR  (&entry_exit_blocks[1])
 335
 336 #define BLOCK_NUM(INSN)       (BLOCK_FOR_INSN (INSN)->index + 0)
 337 #define set_block_for_insn(INSN, BB)  (BLOCK_FOR_INSN (INSN) = BB)
 338
 339 extern void compute_bb_for_insn (void);
 340 extern void free_bb_for_insn (void);
 341 extern void update_bb_for_insn (basic_block);
 342
 343 extern void free_basic_block_vars (int);
 344
 345 extern void insert_insn_on_edge (rtx, edge);
 346 bool safe_insert_insn_on_edge (rtx, edge);
 347
 348 extern void commit_edge_insertions (void);
 349 extern void commit_edge_insertions_watch_calls (void);
 350
 351 extern void remove_fake_edges (void);
 352 extern void add_noreturn_fake_exit_edges (void);
 353 extern void connect_infinite_loops_to_exit (void);
 354 extern int flow_call_edges_add (sbitmap);
 355 extern edge unchecked_make_edge (basic_block, basic_block, int);
 356 extern edge cached_make_edge (sbitmap *, basic_block, basic_block, int);
 357 extern edge make_edge (basic_block, basic_block, int);
 358 extern edge make_single_succ_edge (basic_block, basic_block, int);
 359 extern void remove_edge (edge);
 360 extern void redirect_edge_succ (edge, basic_block);
 361 extern edge redirect_edge_succ_nodup (edge, basic_block);
 362 extern void redirect_edge_pred (edge, basic_block);
 363 extern basic_block create_basic_block_structure (rtx, rtx, rtx, basic_block);
 364 extern void clear_bb_flags (void);
 365 extern void tidy_fallthru_edge (edge, basic_block, basic_block);
 366 extern void tidy_fallthru_edges (void);
 367 extern void flow_reverse_top_sort_order_compute (int *);
 368 extern int flow_depth_first_order_compute (int *, int *);
 369 extern void flow_preorder_transversal_compute (int *);
 370 extern int dfs_enumerate_from (basic_block, int,
 371                                bool (*)(basic_block, void *),
 372                                basic_block *, int, void *);
 373 extern void dump_edge_info (FILE *, edge, int);
 374 extern void clear_edges (void);
 375 extern void mark_critical_edges (void);
 376 extern rtx first_insn_after_basic_block_note (basic_block);
 377
 378 /* Dominator information for basic blocks.  */
 379
 380 typedef struct dominance_info *dominance_info;
 381
 382 /* Structure to group all of the information to process IF-THEN and
 383    IF-THEN-ELSE blocks for the conditional execution support.  This
 384    needs to be in a public file in case the IFCVT macros call
 385    functions passing the ce_if_block data structure.  */
 386
 387 typedef struct ce_if_block
 388 {
 389   basic_block test_bb;                  /* First test block.  */
 390   basic_block then_bb;                  /* THEN block.  */
 391   basic_block else_bb;                  /* ELSE block or NULL.  */
 392   basic_block join_bb;                  /* Join THEN/ELSE blocks.  */
 393   basic_block last_test_bb;             /* Last bb to hold && or || tests.  */
 394   int num_multiple_test_blocks;         /* # of && and || basic blocks.  */
 395   int num_and_and_blocks;               /* # of && blocks.  */
 396   int num_or_or_blocks;                 /* # of || blocks.  */
 397   int num_multiple_test_insns;          /* # of insns in && and || blocks.  */
 398   int and_and_p;                        /* Complex test is &&.  */
 399   int num_then_insns;                   /* # of insns in THEN block.  */
 400   int num_else_insns;                   /* # of insns in ELSE block.  */
 401   int pass;                             /* Pass number.  */
 402
 403 #ifdef IFCVT_EXTRA_FIELDS
 404   IFCVT_EXTRA_FIELDS                    /* Any machine dependent fields.  */
 405 #endif
 406
 407 } ce_if_block_t;
 408
 409 /* This structure maintains an edge list vector.  */
 410 struct edge_list
 411 {
 412   int num_blocks;
 413   int num_edges;
 414   edge *index_to_edge;
 415 };
 416
 417 /* This is the value which indicates no edge is present.  */
 418 #define EDGE_INDEX_NO_EDGE      -1
 419
 420 /* EDGE_INDEX returns an integer index for an edge, or EDGE_INDEX_NO_EDGE
 421    if there is no edge between the 2 basic blocks.  */
 422 #define EDGE_INDEX(el, pred, succ) (find_edge_index ((el), (pred), (succ)))
 423
 424 /* INDEX_EDGE_PRED_BB and INDEX_EDGE_SUCC_BB return a pointer to the basic
 425    block which is either the pred or succ end of the indexed edge.  */
 426 #define INDEX_EDGE_PRED_BB(el, index)   ((el)->index_to_edge[(index)]->src)
 427 #define INDEX_EDGE_SUCC_BB(el, index)   ((el)->index_to_edge[(index)]->dest)
 428
 429 /* INDEX_EDGE returns a pointer to the edge.  */
 430 #define INDEX_EDGE(el, index)           ((el)->index_to_edge[(index)])
 431
 432 /* Number of edges in the compressed edge list.  */
 433 #define NUM_EDGES(el)                   ((el)->num_edges)
 434
 435 /* BB is assumed to contain conditional jump.  Return the fallthru edge.  */
 436 #define FALLTHRU_EDGE(bb)               ((bb)->succ->flags & EDGE_FALLTHRU \
 437                                          ? (bb)->succ : (bb)->succ->succ_next)
 438
 439 /* BB is assumed to contain conditional jump.  Return the branch edge.  */
 440 #define BRANCH_EDGE(bb)                 ((bb)->succ->flags & EDGE_FALLTHRU \
 441                                          ? (bb)->succ->succ_next : (bb)->succ)
 442
 443 /* Return expected execution frequency of the edge E.  */
 444 #define EDGE_FREQUENCY(e)               (((e)->src->frequency \
 445                                           * (e)->probability \
 446                                           + REG_BR_PROB_BASE / 2) \
 447                                          / REG_BR_PROB_BASE)
 448
 449 /* Return nonzero if edge is critical.  */
 450 #define EDGE_CRITICAL_P(e)              ((e)->src->succ->succ_next \
 451                                          && (e)->dest->pred->pred_next)
 452
 453 struct edge_list * create_edge_list (void);
 454 void free_edge_list (struct edge_list *);
 455 void print_edge_list (FILE *, struct edge_list *);
 456 void verify_edge_list (FILE *, struct edge_list *);
 457 int find_edge_index (struct edge_list *, basic_block, basic_block);
 458
 459
 460 enum update_life_extent
 461 {
 462   UPDATE_LIFE_LOCAL = 0,
 463   UPDATE_LIFE_GLOBAL = 1,
 464   UPDATE_LIFE_GLOBAL_RM_NOTES = 2
 465 };
 466
 467 /* Flags for life_analysis and update_life_info.  */
 468
 469 #define PROP_DEATH_NOTES        1       /* Create DEAD and UNUSED notes.  */
 470 #define PROP_LOG_LINKS          2       /* Create LOG_LINKS.  */
 471 #define PROP_REG_INFO           4       /* Update regs_ever_live et al.  */
 472 #define PROP_KILL_DEAD_CODE     8       /* Remove dead code.  */
 473 #define PROP_SCAN_DEAD_CODE     16      /* Scan for dead code.  */
 474 #define PROP_ALLOW_CFG_CHANGES  32      /* Allow the CFG to be changed
 475                                            by dead code removal.  */
 476 #define PROP_AUTOINC            64      /* Create autoinc mem references.  */
 477 #define PROP_EQUAL_NOTES        128     /* Take into account REG_EQUAL notes.  */
 478 #define PROP_SCAN_DEAD_STORES   256     /* Scan for dead code.  */
 479 #define PROP_FINAL              (PROP_DEATH_NOTES | PROP_LOG_LINKS  \
 480                                  | PROP_REG_INFO | PROP_KILL_DEAD_CODE  \
 481                                  | PROP_SCAN_DEAD_CODE | PROP_AUTOINC \
 482                                  | PROP_ALLOW_CFG_CHANGES \
 483                                  | PROP_SCAN_DEAD_STORES)
 484
 485 #define CLEANUP_EXPENSIVE       1       /* Do relatively expensive optimizations
 486                                            except for edge forwarding */
 487 #define CLEANUP_CROSSJUMP       2       /* Do crossjumping.  */
 488 #define CLEANUP_POST_REGSTACK   4       /* We run after reg-stack and need
 489                                            to care REG_DEAD notes.  */
 490 #define CLEANUP_PRE_SIBCALL     8       /* Do not get confused by code hidden
 491                                            inside call_placeholders..  */
 492 #define CLEANUP_PRE_LOOP        16      /* Take care to preserve syntactic loop
 493                                            notes.  */
 494 #define CLEANUP_UPDATE_LIFE     32      /* Keep life information up to date.  */
 495 #define CLEANUP_THREADING       64      /* Do jump threading.  */
 496 #define CLEANUP_NO_INSN_DEL     128     /* Do not try to delete trivially dead
 497                                            insns.  */
 498 #define CLEANUP_CFGLAYOUT       256     /* Do cleanup in cfglayout mode.  */
 499 extern void life_analysis (rtx, FILE *, int);
 500 extern int update_life_info (sbitmap, enum update_life_extent, int);
 501 extern int update_life_info_in_dirty_blocks (enum update_life_extent, int);
 502 extern int count_or_remove_death_notes (sbitmap, int);
 503 extern int propagate_block (basic_block, regset, regset, regset, int);
 504
 505 struct propagate_block_info;
 506 extern rtx propagate_one_insn (struct propagate_block_info *, rtx);
 507 extern struct propagate_block_info *init_propagate_block_info
 508  (basic_block, regset, regset, regset, int);
 509 extern void free_propagate_block_info (struct propagate_block_info *);
 510
 511 /* In lcm.c */
 512 extern struct edge_list *pre_edge_lcm (FILE *, int, sbitmap *, sbitmap *,
 513                                        sbitmap *, sbitmap *, sbitmap **,
 514                                        sbitmap **);
 515 extern struct edge_list *pre_edge_rev_lcm (FILE *, int, sbitmap *,
 516                                            sbitmap *, sbitmap *,
 517                                            sbitmap *, sbitmap **,
 518                                            sbitmap **);
 519 extern void compute_available (sbitmap *, sbitmap *, sbitmap *, sbitmap *);
 520 extern int optimize_mode_switching (FILE *);
 521
 522 /* In emit-rtl.c.  */
 523 extern rtx emit_block_insn_after (rtx, rtx, basic_block);
 524 extern rtx emit_block_insn_before (rtx, rtx, basic_block);
 525
 526 /* In predict.c */
 527 extern void estimate_probability (struct loops *);
 528 extern void note_prediction_to_br_prob (void);
 529 extern void expected_value_to_br_prob (void);
 530 extern bool maybe_hot_bb_p (basic_block);
 531 extern bool probably_cold_bb_p (basic_block);
 532 extern bool probably_never_executed_bb_p (basic_block);
 533
 534 /* In flow.c */
 535 extern void init_flow (void);
 536 extern void dump_bb (basic_block, FILE *);
 537 extern void debug_bb (basic_block);
 538 extern basic_block debug_bb_n (int);
 539 extern void dump_regset (regset, FILE *);
 540 extern void debug_regset (regset);
 541 extern void allocate_reg_life_data (void);
 542 extern void allocate_bb_life_data (void);
 543 extern void expunge_block (basic_block);
 544 extern void link_block (basic_block, basic_block);
 545 extern void unlink_block (basic_block);
 546 extern void compact_blocks (void);
 547 extern basic_block alloc_block (void);
 548 extern void find_unreachable_blocks (void);
 549 extern int delete_noop_moves (rtx);
 550 extern basic_block force_nonfallthru (edge);
 551 extern rtx block_label (basic_block);
 552 extern bool forwarder_block_p (basic_block);
 553 extern bool purge_all_dead_edges (int);
 554 extern bool purge_dead_edges (basic_block);
 555 extern void find_sub_basic_blocks (basic_block);
 556 extern void find_many_sub_basic_blocks (sbitmap);
 557 extern bool can_fallthru (basic_block, basic_block);
 558 extern void flow_nodes_print (const char *, const sbitmap, FILE *);
 559 extern void flow_edge_list_print (const char *, const edge *, int, FILE *);
 560 extern void alloc_aux_for_block (basic_block, int);
 561 extern void alloc_aux_for_blocks (int);
 562 extern void clear_aux_for_blocks (void);
 563 extern void free_aux_for_blocks (void);
 564 extern void alloc_aux_for_edge (edge, int);
 565 extern void alloc_aux_for_edges (int);
 566 extern void clear_aux_for_edges (void);
 567 extern void free_aux_for_edges (void);
 568
 569 /* This function is always defined so it can be called from the
 570    debugger, and it is declared extern so we don't get warnings about
 571    it being unused.  */
 572 extern void verify_flow_info (void);
 573
 574 typedef struct conflict_graph_def *conflict_graph;
 575
 576 /* Callback function when enumerating conflicts.  The arguments are
 577    the smaller and larger regno in the conflict.  Returns zero if
 578    enumeration is to continue, nonzero to halt enumeration.  */
 579 typedef int (*conflict_graph_enum_fn) (int, int, void *);
 580
 581
 582 /* Prototypes of operations on conflict graphs.  */
 583
 584 extern conflict_graph conflict_graph_new
 585  (int);
 586 extern void conflict_graph_delete (conflict_graph);
 587 extern int conflict_graph_add (conflict_graph, int, int);
 588 extern int conflict_graph_conflict_p (conflict_graph, int, int);
 589 extern void conflict_graph_enum (conflict_graph, int, conflict_graph_enum_fn,
 590                                  void *);
 591 extern void conflict_graph_merge_regs (conflict_graph, int, int);
 592 extern void conflict_graph_print (conflict_graph, FILE*);
 593 extern conflict_graph conflict_graph_compute (regset, partition);
 594 extern bool mark_dfs_back_edges (void);
 595 extern void set_edge_can_fallthru_flag (void);
 596 extern void update_br_prob_note (basic_block);
 597 extern void fixup_abnormal_edges (void);
 598 extern bool can_hoist_insn_p (rtx, rtx, regset);
 599 extern rtx hoist_insn_after (rtx, rtx, rtx, rtx);
 600 extern rtx hoist_insn_to_edge (rtx, edge, rtx, rtx);
 601 extern bool inside_basic_block_p (rtx);
 602 extern bool control_flow_insn_p (rtx);
 603
 604 /* In bb-reorder.c */
 605 extern void reorder_basic_blocks (void);
 606
 607 /* In dominance.c */
 608
 609 enum cdi_direction
 610 {
 611   CDI_DOMINATORS,
 612   CDI_POST_DOMINATORS
 613 };
 614
 615 extern dominance_info calculate_dominance_info (enum cdi_direction);
 616 extern void free_dominance_info (dominance_info);
 617 extern basic_block nearest_common_dominator (dominance_info,
 618                                              basic_block, basic_block);
 619 extern void set_immediate_dominator (dominance_info, basic_block,
 620                                      basic_block);
 621 extern basic_block get_immediate_dominator (dominance_info, basic_block);
 622 extern bool dominated_by_p (dominance_info, basic_block, basic_block);
 623 extern int get_dominated_by (dominance_info, basic_block, basic_block **);
 624 extern void add_to_dominance_info (dominance_info, basic_block);
 625 extern void delete_from_dominance_info (dominance_info, basic_block);
 626 basic_block recount_dominator (dominance_info, basic_block);
 627 extern void redirect_immediate_dominators (dominance_info, basic_block,
 628                                            basic_block);
 629 void iterate_fix_dominators (dominance_info, basic_block *, int);
 630 extern void verify_dominators (dominance_info);
 631
 632 #include "cfghooks.h"
 633
 634 #endif /* GCC_BASIC_BLOCK_H */