gcc/basic-block.h

   1 /* Define control and data flow tables, and regsets.
   2    Copyright (C) 1987, 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004
   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_LOOP_EXIT          512     /* Exit of a loop.  */
 156 #define EDGE_ALL_FLAGS          1023
 157
 158 #define EDGE_COMPLEX    (EDGE_ABNORMAL | EDGE_ABNORMAL_CALL | EDGE_EH)
 159
 160 /* Counter summary from the last set of coverage counts read by
 161    profile.c.  */
 162 extern const struct gcov_ctr_summary *profile_info;
 163
 164 /* Declared in cfgloop.h.  */
 165 struct loop;
 166 struct loops;
 167
 168 /* A basic block is a sequence of instructions with only entry and
 169    only one exit.  If any one of the instructions are executed, they
 170    will all be executed, and in sequence from first to last.
 171
 172    There may be COND_EXEC instructions in the basic block.  The
 173    COND_EXEC *instructions* will be executed -- but if the condition
 174    is false the conditionally executed *expressions* will of course
 175    not be executed.  We don't consider the conditionally executed
 176    expression (which might have side-effects) to be in a separate
 177    basic block because the program counter will always be at the same
 178    location after the COND_EXEC instruction, regardless of whether the
 179    condition is true or not.
 180
 181    Basic blocks need not start with a label nor end with a jump insn.
 182    For example, a previous basic block may just "conditionally fall"
 183    into the succeeding basic block, and the last basic block need not
 184    end with a jump insn.  Block 0 is a descendant of the entry block.
 185
 186    A basic block beginning with two labels cannot have notes between
 187    the labels.
 188
 189    Data for jump tables are stored in jump_insns that occur in no
 190    basic block even though these insns can follow or precede insns in
 191    basic blocks.  */
 192
 193 /* Basic block information indexed by block number.  */
 194 typedef struct basic_block_def {
 195   /* The first and last insns of the block.  */
 196   rtx head_, end_;
 197
 198   /* The first and last trees of the block.  */
 199   tree head_tree;
 200   tree end_tree;
 201
 202   /* The edges into and out of the block.  */
 203   edge pred, succ;
 204
 205   /* Liveness info.  */
 206
 207   /* The registers that are modified within this in block.  */
 208   regset local_set;
 209   /* The registers that are conditionally modified within this block.
 210      In other words, registers that are set only as part of a
 211      COND_EXEC.  */
 212   regset cond_local_set;
 213   /* The registers that are live on entry to this block.
 214
 215      Note that in SSA form, global_live_at_start does not reflect the
 216      use of regs in phi functions, since the liveness of these regs
 217      may depend on which edge was taken into the block.  */
 218   regset global_live_at_start;
 219   /* The registers that are live on exit from this block.  */
 220   regset global_live_at_end;
 221
 222   /* Auxiliary info specific to a pass.  */
 223   void *aux;
 224
 225   /* The index of this block.  */
 226   int index;
 227
 228   /* Previous and next blocks in the chain.  */
 229   struct basic_block_def *prev_bb, *next_bb;
 230
 231   /* The loop depth of this block.  */
 232   int loop_depth;
 233
 234   /* Outermost loop containing the block.  */
 235   struct loop *loop_father;
 236
 237   /* The dominance and postdominance information node.  */
 238   struct et_node *dom[2];
 239
 240   /* Expected number of executions: calculated in profile.c.  */
 241   gcov_type count;
 242
 243   /* Expected frequency.  Normalized to be in range 0 to BB_FREQ_MAX.  */
 244   int frequency;
 245
 246   /* Various flags.  See BB_* below.  */
 247   int flags;
 248
 249   /* Additional data maintained by cfg_layout routines.  */
 250   struct reorder_block_def *rbi;
 251 } *basic_block;
 252
 253 #define BB_FREQ_MAX 10000
 254
 255 /* Masks for basic_block.flags.  */
 256 #define BB_DIRTY                1
 257 #define BB_NEW                  2
 258 #define BB_REACHABLE            4
 259 #define BB_VISITED              8
 260 #define BB_IRREDUCIBLE_LOOP     16
 261 #define BB_SUPERBLOCK           32
 262
 263 /* Number of basic blocks in the current function.  */
 264
 265 extern int n_basic_blocks;
 266
 267 /* First free basic block number.  */
 268
 269 extern int last_basic_block;
 270
 271 /* Number of edges in the current function.  */
 272
 273 extern int n_edges;
 274
 275 /* Index by basic block number, get basic block struct info.  */
 276
 277 extern varray_type basic_block_info;
 278
 279 #define BASIC_BLOCK(N)  (VARRAY_BB (basic_block_info, (N)))
 280
 281 /* For iterating over basic blocks.  */
 282 #define FOR_BB_BETWEEN(BB, FROM, TO, DIR) \
 283   for (BB = FROM; BB != TO; BB = BB->DIR)
 284
 285 #define FOR_EACH_BB(BB) \
 286   FOR_BB_BETWEEN (BB, ENTRY_BLOCK_PTR->next_bb, EXIT_BLOCK_PTR, next_bb)
 287
 288 #define FOR_EACH_BB_REVERSE(BB) \
 289   FOR_BB_BETWEEN (BB, EXIT_BLOCK_PTR->prev_bb, ENTRY_BLOCK_PTR, prev_bb)
 290
 291 /* Cycles through _all_ basic blocks, even the fake ones (entry and
 292    exit block).  */
 293
 294 #define FOR_ALL_BB(BB) \
 295   for (BB = ENTRY_BLOCK_PTR; BB; BB = BB->next_bb)
 296
 297 /* What registers are live at the setjmp call.  */
 298
 299 extern regset regs_live_at_setjmp;
 300
 301 /* Special labels found during CFG build.  */
 302
 303 extern GTY(()) rtx label_value_list;
 304 extern GTY(()) rtx tail_recursion_label_list;
 305
 306 extern struct obstack flow_obstack;
 307
 308 /* Indexed by n, gives number of basic block that  (REG n) is used in.
 309    If the value is REG_BLOCK_GLOBAL (-2),
 310    it means (REG n) is used in more than one basic block.
 311    REG_BLOCK_UNKNOWN (-1) means it hasn't been seen yet so we don't know.
 312    This information remains valid for the rest of the compilation
 313    of the current function; it is used to control register allocation.  */
 314
 315 #define REG_BLOCK_UNKNOWN -1
 316 #define REG_BLOCK_GLOBAL -2
 317
 318 #define REG_BASIC_BLOCK(N) (VARRAY_REG (reg_n_info, N)->basic_block)
 319 \f
 320 /* Stuff for recording basic block info.  */
 321
 322 #define BB_HEAD(B)      (B)->head_
 323 #define BB_END(B)       (B)->end_
 324
 325 /* Special block numbers [markers] for entry and exit.  */
 326 #define ENTRY_BLOCK (-1)
 327 #define EXIT_BLOCK (-2)
 328
 329 /* Special block number not valid for any block.  */
 330 #define INVALID_BLOCK (-3)
 331
 332 /* Similarly, block pointers for the edge list.  */
 333 extern struct basic_block_def entry_exit_blocks[2];
 334 #define ENTRY_BLOCK_PTR (&entry_exit_blocks[0])
 335 #define EXIT_BLOCK_PTR  (&entry_exit_blocks[1])
 336
 337 #define BLOCK_NUM(INSN)       (BLOCK_FOR_INSN (INSN)->index + 0)
 338 #define set_block_for_insn(INSN, BB)  (BLOCK_FOR_INSN (INSN) = BB)
 339
 340 extern void compute_bb_for_insn (void);
 341 extern void free_bb_for_insn (void);
 342 extern void update_bb_for_insn (basic_block);
 343
 344 extern void free_basic_block_vars (int);
 345
 346 extern void insert_insn_on_edge (rtx, edge);
 347 bool safe_insert_insn_on_edge (rtx, edge);
 348
 349 extern void commit_edge_insertions (void);
 350 extern void commit_edge_insertions_watch_calls (void);
 351
 352 extern void remove_fake_edges (void);
 353 extern void add_noreturn_fake_exit_edges (void);
 354 extern void connect_infinite_loops_to_exit (void);
 355 extern int flow_call_edges_add (sbitmap);
 356 extern edge unchecked_make_edge (basic_block, basic_block, int);
 357 extern edge cached_make_edge (sbitmap *, basic_block, basic_block, int);
 358 extern edge make_edge (basic_block, basic_block, int);
 359 extern edge make_single_succ_edge (basic_block, basic_block, int);
 360 extern void remove_edge (edge);
 361 extern void redirect_edge_succ (edge, basic_block);
 362 extern edge redirect_edge_succ_nodup (edge, basic_block);
 363 extern void redirect_edge_pred (edge, basic_block);
 364 extern basic_block create_basic_block_structure (rtx, rtx, rtx, basic_block);
 365 extern void clear_bb_flags (void);
 366 extern void tidy_fallthru_edge (edge, basic_block, basic_block);
 367 extern void tidy_fallthru_edges (void);
 368 extern void flow_reverse_top_sort_order_compute (int *);
 369 extern int flow_depth_first_order_compute (int *, int *);
 370 extern void flow_preorder_transversal_compute (int *);
 371 extern int dfs_enumerate_from (basic_block, int,
 372                                bool (*)(basic_block, void *),
 373                                basic_block *, int, void *);
 374 extern void dump_edge_info (FILE *, edge, int);
 375 extern void clear_edges (void);
 376 extern void mark_critical_edges (void);
 377 extern rtx first_insn_after_basic_block_note (basic_block);
 378
 379 /* Structure to group all of the information to process IF-THEN and
 380    IF-THEN-ELSE blocks for the conditional execution support.  This
 381    needs to be in a public file in case the IFCVT macros call
 382    functions passing the ce_if_block data structure.  */
 383
 384 typedef struct ce_if_block
 385 {
 386   basic_block test_bb;                  /* First test block.  */
 387   basic_block then_bb;                  /* THEN block.  */
 388   basic_block else_bb;                  /* ELSE block or NULL.  */
 389   basic_block join_bb;                  /* Join THEN/ELSE blocks.  */
 390   basic_block last_test_bb;             /* Last bb to hold && or || tests.  */
 391   int num_multiple_test_blocks;         /* # of && and || basic blocks.  */
 392   int num_and_and_blocks;               /* # of && blocks.  */
 393   int num_or_or_blocks;                 /* # of || blocks.  */
 394   int num_multiple_test_insns;          /* # of insns in && and || blocks.  */
 395   int and_and_p;                        /* Complex test is &&.  */
 396   int num_then_insns;                   /* # of insns in THEN block.  */
 397   int num_else_insns;                   /* # of insns in ELSE block.  */
 398   int pass;                             /* Pass number.  */
 399
 400 #ifdef IFCVT_EXTRA_FIELDS
 401   IFCVT_EXTRA_FIELDS                    /* Any machine dependent fields.  */
 402 #endif
 403
 404 } ce_if_block_t;
 405
 406 /* This structure maintains an edge list vector.  */
 407 struct edge_list
 408 {
 409   int num_blocks;
 410   int num_edges;
 411   edge *index_to_edge;
 412 };
 413
 414 /* This is the value which indicates no edge is present.  */
 415 #define EDGE_INDEX_NO_EDGE      -1
 416
 417 /* EDGE_INDEX returns an integer index for an edge, or EDGE_INDEX_NO_EDGE
 418    if there is no edge between the 2 basic blocks.  */
 419 #define EDGE_INDEX(el, pred, succ) (find_edge_index ((el), (pred), (succ)))
 420
 421 /* INDEX_EDGE_PRED_BB and INDEX_EDGE_SUCC_BB return a pointer to the basic
 422    block which is either the pred or succ end of the indexed edge.  */
 423 #define INDEX_EDGE_PRED_BB(el, index)   ((el)->index_to_edge[(index)]->src)
 424 #define INDEX_EDGE_SUCC_BB(el, index)   ((el)->index_to_edge[(index)]->dest)
 425
 426 /* INDEX_EDGE returns a pointer to the edge.  */
 427 #define INDEX_EDGE(el, index)           ((el)->index_to_edge[(index)])
 428
 429 /* Number of edges in the compressed edge list.  */
 430 #define NUM_EDGES(el)                   ((el)->num_edges)
 431
 432 /* BB is assumed to contain conditional jump.  Return the fallthru edge.  */
 433 #define FALLTHRU_EDGE(bb)               ((bb)->succ->flags & EDGE_FALLTHRU \
 434                                          ? (bb)->succ : (bb)->succ->succ_next)
 435
 436 /* BB is assumed to contain conditional jump.  Return the branch edge.  */
 437 #define BRANCH_EDGE(bb)                 ((bb)->succ->flags & EDGE_FALLTHRU \
 438                                          ? (bb)->succ->succ_next : (bb)->succ)
 439
 440 /* Return expected execution frequency of the edge E.  */
 441 #define EDGE_FREQUENCY(e)               (((e)->src->frequency \
 442                                           * (e)->probability \
 443                                           + REG_BR_PROB_BASE / 2) \
 444                                          / REG_BR_PROB_BASE)
 445
 446 /* Return nonzero if edge is critical.  */
 447 #define EDGE_CRITICAL_P(e)              ((e)->src->succ->succ_next \
 448                                          && (e)->dest->pred->pred_next)
 449
 450 struct edge_list * create_edge_list (void);
 451 void free_edge_list (struct edge_list *);
 452 void print_edge_list (FILE *, struct edge_list *);
 453 void verify_edge_list (FILE *, struct edge_list *);
 454 int find_edge_index (struct edge_list *, basic_block, basic_block);
 455
 456
 457 enum update_life_extent
 458 {
 459   UPDATE_LIFE_LOCAL = 0,
 460   UPDATE_LIFE_GLOBAL = 1,
 461   UPDATE_LIFE_GLOBAL_RM_NOTES = 2
 462 };
 463
 464 /* Flags for life_analysis and update_life_info.  */
 465
 466 #define PROP_DEATH_NOTES        1       /* Create DEAD and UNUSED notes.  */
 467 #define PROP_LOG_LINKS          2       /* Create LOG_LINKS.  */
 468 #define PROP_REG_INFO           4       /* Update regs_ever_live et al.  */
 469 #define PROP_KILL_DEAD_CODE     8       /* Remove dead code.  */
 470 #define PROP_SCAN_DEAD_CODE     16      /* Scan for dead code.  */
 471 #define PROP_ALLOW_CFG_CHANGES  32      /* Allow the CFG to be changed
 472                                            by dead code removal.  */
 473 #define PROP_AUTOINC            64      /* Create autoinc mem references.  */
 474 #define PROP_EQUAL_NOTES        128     /* Take into account REG_EQUAL notes.  */
 475 #define PROP_SCAN_DEAD_STORES   256     /* Scan for dead code.  */
 476 #define PROP_ASM_SCAN           512     /* Internal flag used within flow.c
 477                                            to flag analysis of asms.  */
 478 #define PROP_FINAL              (PROP_DEATH_NOTES | PROP_LOG_LINKS  \
 479                                  | PROP_REG_INFO | PROP_KILL_DEAD_CODE  \
 480                                  | PROP_SCAN_DEAD_CODE | PROP_AUTOINC \
 481                                  | PROP_ALLOW_CFG_CHANGES \
 482                                  | PROP_SCAN_DEAD_STORES)
 483
 484 #define CLEANUP_EXPENSIVE       1       /* Do relatively expensive optimizations
 485                                            except for edge forwarding */
 486 #define CLEANUP_CROSSJUMP       2       /* Do crossjumping.  */
 487 #define CLEANUP_POST_REGSTACK   4       /* We run after reg-stack and need
 488                                            to care REG_DEAD notes.  */
 489 #define CLEANUP_PRE_SIBCALL     8       /* Do not get confused by code hidden
 490                                            inside call_placeholders..  */
 491 #define CLEANUP_PRE_LOOP        16      /* Take care to preserve syntactic loop
 492                                            notes.  */
 493 #define CLEANUP_UPDATE_LIFE     32      /* Keep life information up to date.  */
 494 #define CLEANUP_THREADING       64      /* Do jump threading.  */
 495 #define CLEANUP_NO_INSN_DEL     128     /* Do not try to delete trivially dead
 496                                            insns.  */
 497 #define CLEANUP_CFGLAYOUT       256     /* Do cleanup in cfglayout mode.  */
 498 extern void life_analysis (rtx, FILE *, int);
 499 extern int update_life_info (sbitmap, enum update_life_extent, int);
 500 extern int update_life_info_in_dirty_blocks (enum update_life_extent, int);
 501 extern int count_or_remove_death_notes (sbitmap, int);
 502 extern int propagate_block (basic_block, regset, regset, regset, int);
 503
 504 struct propagate_block_info;
 505 extern rtx propagate_one_insn (struct propagate_block_info *, rtx);
 506 extern struct propagate_block_info *init_propagate_block_info
 507  (basic_block, regset, regset, regset, int);
 508 extern void free_propagate_block_info (struct propagate_block_info *);
 509
 510 /* In lcm.c */
 511 extern struct edge_list *pre_edge_lcm (FILE *, int, sbitmap *, sbitmap *,
 512                                        sbitmap *, sbitmap *, sbitmap **,
 513                                        sbitmap **);
 514 extern struct edge_list *pre_edge_rev_lcm (FILE *, int, sbitmap *,
 515                                            sbitmap *, sbitmap *,
 516                                            sbitmap *, sbitmap **,
 517                                            sbitmap **);
 518 extern void compute_available (sbitmap *, sbitmap *, sbitmap *, sbitmap *);
 519 extern int optimize_mode_switching (FILE *);
 520
 521 /* In emit-rtl.c.  */
 522 extern rtx emit_block_insn_after (rtx, rtx, basic_block);
 523 extern rtx emit_block_insn_before (rtx, rtx, basic_block);
 524
 525 /* In predict.c */
 526 extern void estimate_probability (struct loops *);
 527 extern void note_prediction_to_br_prob (void);
 528 extern void expected_value_to_br_prob (void);
 529 extern bool maybe_hot_bb_p (basic_block);
 530 extern bool probably_cold_bb_p (basic_block);
 531 extern bool probably_never_executed_bb_p (basic_block);
 532
 533 /* In flow.c */
 534 extern void init_flow (void);
 535 extern void dump_bb (basic_block, FILE *);
 536 extern void debug_bb (basic_block);
 537 extern basic_block debug_bb_n (int);
 538 extern void dump_regset (regset, FILE *);
 539 extern void debug_regset (regset);
 540 extern void allocate_reg_life_data (void);
 541 extern void allocate_bb_life_data (void);
 542 extern void expunge_block (basic_block);
 543 extern void link_block (basic_block, basic_block);
 544 extern void unlink_block (basic_block);
 545 extern void compact_blocks (void);
 546 extern basic_block alloc_block (void);
 547 extern void find_unreachable_blocks (void);
 548 extern int delete_noop_moves (rtx);
 549 extern basic_block force_nonfallthru (edge);
 550 extern rtx block_label (basic_block);
 551 extern bool forwarder_block_p (basic_block);
 552 extern bool purge_all_dead_edges (int);
 553 extern bool purge_dead_edges (basic_block);
 554 extern void find_sub_basic_blocks (basic_block);
 555 extern void find_many_sub_basic_blocks (sbitmap);
 556 extern bool can_fallthru (basic_block, basic_block);
 557 extern void flow_nodes_print (const char *, const sbitmap, FILE *);
 558 extern void flow_edge_list_print (const char *, const edge *, int, FILE *);
 559 extern void alloc_aux_for_block (basic_block, int);
 560 extern void alloc_aux_for_blocks (int);
 561 extern void clear_aux_for_blocks (void);
 562 extern void free_aux_for_blocks (void);
 563 extern void alloc_aux_for_edge (edge, int);
 564 extern void alloc_aux_for_edges (int);
 565 extern void clear_aux_for_edges (void);
 566 extern void free_aux_for_edges (void);
 567
 568 /* This function is always defined so it can be called from the
 569    debugger, and it is declared extern so we don't get warnings about
 570    it being unused.  */
 571 extern void verify_flow_info (void);
 572
 573 typedef struct conflict_graph_def *conflict_graph;
 574
 575 /* Callback function when enumerating conflicts.  The arguments are
 576    the smaller and larger regno in the conflict.  Returns zero if
 577    enumeration is to continue, nonzero to halt enumeration.  */
 578 typedef int (*conflict_graph_enum_fn) (int, int, void *);
 579
 580
 581 /* Prototypes of operations on conflict graphs.  */
 582
 583 extern conflict_graph conflict_graph_new
 584  (int);
 585 extern void conflict_graph_delete (conflict_graph);
 586 extern int conflict_graph_add (conflict_graph, int, int);
 587 extern int conflict_graph_conflict_p (conflict_graph, int, int);
 588 extern void conflict_graph_enum (conflict_graph, int, conflict_graph_enum_fn,
 589                                  void *);
 590 extern void conflict_graph_merge_regs (conflict_graph, int, int);
 591 extern void conflict_graph_print (conflict_graph, FILE*);
 592 extern conflict_graph conflict_graph_compute (regset, partition);
 593 extern bool mark_dfs_back_edges (void);
 594 extern void set_edge_can_fallthru_flag (void);
 595 extern void update_br_prob_note (basic_block);
 596 extern void fixup_abnormal_edges (void);
 597 extern bool can_hoist_insn_p (rtx, rtx, regset);
 598 extern rtx hoist_insn_after (rtx, rtx, rtx, rtx);
 599 extern rtx hoist_insn_to_edge (rtx, edge, rtx, rtx);
 600 extern bool inside_basic_block_p (rtx);
 601 extern bool control_flow_insn_p (rtx);
 602
 603 /* In bb-reorder.c */
 604 extern void reorder_basic_blocks (void);
 605
 606 /* In dominance.c */
 607
 608 enum cdi_direction
 609 {
 610   CDI_DOMINATORS,
 611   CDI_POST_DOMINATORS
 612 };
 613
 614 enum dom_state
 615 {
 616   DOM_NONE,             /* Not computed at all.  */
 617   DOM_CONS_OK,          /* The data is conservatively OK, i.e. if it says you that A dominates B,
 618                            it indeed does.  */
 619   DOM_NO_FAST_QUERY,    /* The data is OK, but the fast query data are not usable.  */
 620   DOM_OK                /* Everything is ok.  */
 621 };
 622
 623 extern enum dom_state dom_computed[2];
 624
 625 extern void calculate_dominance_info (enum cdi_direction);
 626 extern void free_dominance_info (enum cdi_direction);
 627 extern basic_block nearest_common_dominator (enum cdi_direction,
 628                                              basic_block, basic_block);
 629 extern void set_immediate_dominator (enum cdi_direction, basic_block,
 630                                      basic_block);
 631 extern basic_block get_immediate_dominator (enum cdi_direction, basic_block);
 632 extern bool dominated_by_p (enum cdi_direction, basic_block, basic_block);
 633 extern int get_dominated_by (enum cdi_direction, basic_block, basic_block **);
 634 extern void add_to_dominance_info (enum cdi_direction, basic_block);
 635 extern void delete_from_dominance_info (enum cdi_direction, basic_block);
 636 basic_block recount_dominator (enum cdi_direction, basic_block);
 637 extern void redirect_immediate_dominators (enum cdi_direction, basic_block,
 638                                            basic_block);
 639 extern void iterate_fix_dominators (enum cdi_direction, basic_block *, int);
 640 extern void verify_dominators (enum cdi_direction);
 641 extern basic_block first_dom_son (enum cdi_direction, basic_block);
 642 extern basic_block next_dom_son (enum cdi_direction, basic_block);
 643 extern bool try_redirect_by_replacing_jump (edge, basic_block, bool);
 644
 645 #include "cfghooks.h"
 646
 647 #endif /* GCC_BASIC_BLOCK_H */