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 #include "predict.h"
  31
  32 /* Head of register set linked list.  */
  33 typedef bitmap_head regset_head;
  34
  35 /* A pointer to a regset_head.  */
  36 typedef bitmap regset;
  37
  38 /* Initialize a new regset.  */
  39 #define INIT_REG_SET(HEAD) bitmap_initialize (HEAD, 1)
  40
  41 /* Clear a register set by freeing up the linked list.  */
  42 #define CLEAR_REG_SET(HEAD) bitmap_clear (HEAD)
  43
  44 /* Copy a register set to another register set.  */
  45 #define COPY_REG_SET(TO, FROM) bitmap_copy (TO, FROM)
  46
  47 /* Compare two register sets.  */
  48 #define REG_SET_EQUAL_P(A, B) bitmap_equal_p (A, B)
  49
  50 /* `and' a register set with a second register set.  */
  51 #define AND_REG_SET(TO, FROM) bitmap_operation (TO, TO, FROM, BITMAP_AND)
  52
  53 /* `and' the complement of a register set with a register set.  */
  54 #define AND_COMPL_REG_SET(TO, FROM) \
  55   bitmap_operation (TO, TO, FROM, BITMAP_AND_COMPL)
  56
  57 /* Inclusive or a register set with a second register set.  */
  58 #define IOR_REG_SET(TO, FROM) bitmap_operation (TO, TO, FROM, BITMAP_IOR)
  59
  60 /* Exclusive or a register set with a second register set.  */
  61 #define XOR_REG_SET(TO, FROM) bitmap_operation (TO, TO, FROM, BITMAP_XOR)
  62
  63 /* Or into TO the register set FROM1 `and'ed with the complement of FROM2.  */
  64 #define IOR_AND_COMPL_REG_SET(TO, FROM1, FROM2) \
  65   bitmap_ior_and_compl (TO, FROM1, FROM2)
  66
  67 /* Clear a single register in a register set.  */
  68 #define CLEAR_REGNO_REG_SET(HEAD, REG) bitmap_clear_bit (HEAD, REG)
  69
  70 /* Set a single register in a register set.  */
  71 #define SET_REGNO_REG_SET(HEAD, REG) bitmap_set_bit (HEAD, REG)
  72
  73 /* Return true if a register is set in a register set.  */
  74 #define REGNO_REG_SET_P(TO, REG) bitmap_bit_p (TO, REG)
  75
  76 /* Copy the hard registers in a register set to the hard register set.  */
  77 extern void reg_set_to_hard_reg_set (HARD_REG_SET *, bitmap);
  78 #define REG_SET_TO_HARD_REG_SET(TO, FROM)                               \
  79 do {                                                                    \
  80   CLEAR_HARD_REG_SET (TO);                                              \
  81   reg_set_to_hard_reg_set (&TO, FROM);                                  \
  82 } while (0)
  83
  84 /* Loop over all registers in REGSET, starting with MIN, setting REGNUM to the
  85    register number and executing CODE for all registers that are set.  */
  86 #define EXECUTE_IF_SET_IN_REG_SET(REGSET, MIN, REGNUM, CODE)            \
  87   EXECUTE_IF_SET_IN_BITMAP (REGSET, MIN, REGNUM, CODE)
  88
  89 /* Loop over all registers in REGSET1 and REGSET2, starting with MIN, setting
  90    REGNUM to the register number and executing CODE for all registers that are
  91    set in the first regset and not set in the second.  */
  92 #define EXECUTE_IF_AND_COMPL_IN_REG_SET(REGSET1, REGSET2, MIN, REGNUM, CODE) \
  93   EXECUTE_IF_AND_COMPL_IN_BITMAP (REGSET1, REGSET2, MIN, REGNUM, CODE)
  94
  95 /* Loop over all registers in REGSET1 and REGSET2, starting with MIN, setting
  96    REGNUM to the register number and executing CODE for all registers that are
  97    set in both regsets.  */
  98 #define EXECUTE_IF_AND_IN_REG_SET(REGSET1, REGSET2, MIN, REGNUM, CODE) \
  99   EXECUTE_IF_AND_IN_BITMAP (REGSET1, REGSET2, MIN, REGNUM, CODE)
 100
 101 /* Allocate a register set with oballoc.  */
 102 #define OBSTACK_ALLOC_REG_SET(OBSTACK) BITMAP_OBSTACK_ALLOC (OBSTACK)
 103
 104 /* Initialize a register set.  Returns the new register set.  */
 105 #define INITIALIZE_REG_SET(HEAD) bitmap_initialize (&HEAD, 1)
 106
 107 /* Do any cleanup needed on a regset when it is no longer used.  */
 108 #define FREE_REG_SET(REGSET) BITMAP_FREE(REGSET)
 109
 110 /* Do any one-time initializations needed for regsets.  */
 111 #define INIT_ONCE_REG_SET() BITMAP_INIT_ONCE ()
 112
 113 /* Grow any tables needed when the number of registers is calculated
 114    or extended.  For the linked list allocation, nothing needs to
 115    be done, other than zero the statistics on the first allocation.  */
 116 #define MAX_REGNO_REG_SET(NUM_REGS, NEW_P, RENUMBER_P)
 117
 118 /* Type we use to hold basic block counters.  Should be at least
 119    64bit.  Although a counter cannot be negative, we use a signed
 120    type, because erroneous negative counts can be generated when the
 121    flow graph is manipulated by various optimizations.  A signed type
 122    makes those easy to detect.  */
 123 typedef HOST_WIDEST_INT gcov_type;
 124
 125 /* Control flow edge information.  */
 126 struct edge_def GTY((chain_next ("%h.pred_next")))
 127 {
 128   /* Links through the predecessor and successor lists.  */
 129   struct edge_def *pred_next;
 130   struct edge_def *succ_next;
 131
 132   /* The two blocks at the ends of the edge.  */
 133   struct basic_block_def *src;
 134   struct basic_block_def *dest;
 135
 136   /* Instructions queued on the edge.  */
 137   union edge_def_insns {
 138     rtx GTY ((tag ("0"))) r;
 139     tree GTY ((tag ("1"))) t;
 140   } GTY ((desc ("ir_type ()"))) insns;
 141
 142   /* Auxiliary info specific to a pass.  */
 143   PTR GTY ((skip (""))) aux;
 144
 145   /* Location of any goto implicit in the edge, during tree-ssa.  */
 146   location_t *goto_locus;
 147
 148   int flags;                    /* see EDGE_* below  */
 149   int probability;              /* biased by REG_BR_PROB_BASE */
 150   gcov_type count;              /* Expected number of executions calculated
 151                                    in profile.c  */
 152   bool crossing_edge;           /* Crosses between hot and cold sections, when
 153                                    we do partitioning.  */
 154 };
 155
 156 typedef struct edge_def *edge;
 157
 158 #define EDGE_FALLTHRU           1       /* 'Straight line' flow */
 159 #define EDGE_ABNORMAL           2       /* Strange flow, like computed
 160                                            label, or eh */
 161 #define EDGE_ABNORMAL_CALL      4       /* Call with abnormal exit
 162                                            like an exception, or sibcall */
 163 #define EDGE_EH                 8       /* Exception throw */
 164 #define EDGE_FAKE               16      /* Not a real edge (profile.c) */
 165 #define EDGE_DFS_BACK           32      /* A backwards edge */
 166 #define EDGE_CAN_FALLTHRU       64      /* Candidate for straight line
 167                                            flow.  */
 168 #define EDGE_IRREDUCIBLE_LOOP   128     /* Part of irreducible loop.  */
 169 #define EDGE_SIBCALL            256     /* Edge from sibcall to exit.  */
 170 #define EDGE_LOOP_EXIT          512     /* Exit of a loop.  */
 171 #define EDGE_TRUE_VALUE         1024    /* Edge taken when controlling
 172                                            predicate is non zero.  */
 173 #define EDGE_FALSE_VALUE        2048    /* Edge taken when controlling
 174                                            predicate is zero.  */
 175 #define EDGE_EXECUTABLE         4096    /* Edge is executable.  Only
 176                                            valid during SSA-CCP.  */
 177 #define EDGE_ALL_FLAGS          8191
 178
 179 #define EDGE_COMPLEX    (EDGE_ABNORMAL | EDGE_ABNORMAL_CALL | EDGE_EH)
 180
 181 /* Counter summary from the last set of coverage counts read by
 182    profile.c.  */
 183 extern const struct gcov_ctr_summary *profile_info;
 184
 185 /* Declared in cfgloop.h.  */
 186 struct loop;
 187 struct loops;
 188
 189 /* Declared in tree-flow.h.  */
 190 struct bb_ann_d;
 191
 192 /* A basic block is a sequence of instructions with only entry and
 193    only one exit.  If any one of the instructions are executed, they
 194    will all be executed, and in sequence from first to last.
 195
 196    There may be COND_EXEC instructions in the basic block.  The
 197    COND_EXEC *instructions* will be executed -- but if the condition
 198    is false the conditionally executed *expressions* will of course
 199    not be executed.  We don't consider the conditionally executed
 200    expression (which might have side-effects) to be in a separate
 201    basic block because the program counter will always be at the same
 202    location after the COND_EXEC instruction, regardless of whether the
 203    condition is true or not.
 204
 205    Basic blocks need not start with a label nor end with a jump insn.
 206    For example, a previous basic block may just "conditionally fall"
 207    into the succeeding basic block, and the last basic block need not
 208    end with a jump insn.  Block 0 is a descendant of the entry block.
 209
 210    A basic block beginning with two labels cannot have notes between
 211    the labels.
 212
 213    Data for jump tables are stored in jump_insns that occur in no
 214    basic block even though these insns can follow or precede insns in
 215    basic blocks.  */
 216
 217 /* Basic block information indexed by block number.  */
 218 struct basic_block_def GTY((chain_next ("%h.next_bb"), chain_prev ("%h.prev_bb")))
 219 {
 220   /* The first and last insns of the block.  */
 221   rtx head_;
 222   rtx end_;
 223
 224   /* Pointers to the first and last trees of the block.  */
 225   tree stmt_list;
 226
 227   /* The edges into and out of the block.  */
 228   edge pred;
 229   edge succ;
 230
 231   /* Liveness info.  */
 232
 233   /* The registers that are modified within this in block.  */
 234   bitmap GTY ((skip (""))) local_set;
 235   /* The registers that are conditionally modified within this block.
 236      In other words, registers that are set only as part of a
 237      COND_EXEC.  */
 238   bitmap GTY ((skip (""))) cond_local_set;
 239   /* The registers that are live on entry to this block.
 240
 241      Note that in SSA form, global_live_at_start does not reflect the
 242      use of regs in phi functions, since the liveness of these regs
 243      may depend on which edge was taken into the block.  */
 244   bitmap GTY ((skip (""))) global_live_at_start;
 245   /* The registers that are live on exit from this block.  */
 246   bitmap GTY ((skip (""))) global_live_at_end;
 247
 248   /* Auxiliary info specific to a pass.  */
 249   PTR GTY ((skip (""))) aux;
 250
 251   /* The index of this block.  */
 252   int index;
 253
 254   /* Previous and next blocks in the chain.  */
 255   struct basic_block_def *prev_bb;
 256   struct basic_block_def *next_bb;
 257
 258   /* The loop depth of this block.  */
 259   int loop_depth;
 260
 261   /* Innermost loop containing the block.  */
 262   struct loop * GTY ((skip (""))) loop_father;
 263
 264   /* The dominance and postdominance information node.  */
 265   struct et_node * GTY ((skip (""))) dom[2];
 266
 267   /* Expected number of executions: calculated in profile.c.  */
 268   gcov_type count;
 269
 270   /* Expected frequency.  Normalized to be in range 0 to BB_FREQ_MAX.  */
 271   int frequency;
 272
 273   /* Various flags.  See BB_* below.  */
 274   int flags;
 275
 276   /* Which section block belongs in, when partitioning basic blocks.  */
 277   int partition;
 278
 279   /* The data used by basic block copying and reordering functions.  */
 280   struct reorder_block_def * GTY ((skip (""))) rbi;
 281
 282   /* Annotations used at the tree level.  */
 283   struct bb_ann_d *tree_annotations;
 284 };
 285
 286 typedef struct basic_block_def *basic_block;
 287
 288 /* Structure to hold information about the blocks during reordering and
 289    copying.  */
 290
 291 typedef struct reorder_block_def
 292 {
 293   rtx header;
 294   rtx footer;
 295   basic_block next;
 296   basic_block original;
 297   /* Used by loop copying.  */
 298   basic_block copy;
 299   int duplicated;
 300
 301   /* These fields are used by bb-reorder pass.  */
 302   int visited;
 303 } *reorder_block_def;
 304
 305 #define BB_FREQ_MAX 10000
 306
 307 /* Masks for basic_block.flags.  */
 308 #define BB_DIRTY                1
 309 #define BB_NEW                  2
 310 #define BB_REACHABLE            4
 311 #define BB_VISITED              8
 312 #define BB_IRREDUCIBLE_LOOP     16
 313 #define BB_SUPERBLOCK           32
 314
 315 /* Partitions, to be used when partitioning hot and cold basic blocks into
 316    separate sections.  */
 317 #define UNPARTITIONED   0
 318 #define HOT_PARTITION   1
 319 #define COLD_PARTITION  2
 320
 321 /* Number of basic blocks in the current function.  */
 322
 323 extern int n_basic_blocks;
 324
 325 /* First free basic block number.  */
 326
 327 extern int last_basic_block;
 328
 329 /* Number of edges in the current function.  */
 330
 331 extern int n_edges;
 332
 333 /* Index by basic block number, get basic block struct info.  */
 334
 335 extern GTY(()) varray_type basic_block_info;
 336
 337 #define BASIC_BLOCK(N)  (VARRAY_BB (basic_block_info, (N)))
 338
 339 /* For iterating over basic blocks.  */
 340 #define FOR_BB_BETWEEN(BB, FROM, TO, DIR) \
 341   for (BB = FROM; BB != TO; BB = BB->DIR)
 342
 343 #define FOR_EACH_BB(BB) \
 344   FOR_BB_BETWEEN (BB, ENTRY_BLOCK_PTR->next_bb, EXIT_BLOCK_PTR, next_bb)
 345
 346 #define FOR_EACH_BB_REVERSE(BB) \
 347   FOR_BB_BETWEEN (BB, EXIT_BLOCK_PTR->prev_bb, ENTRY_BLOCK_PTR, prev_bb)
 348
 349 /* For iterating over insns in basic block.  */
 350 #define FOR_BB_INSNS(BB, INSN)                  \
 351   for ((INSN) = BB_HEAD (BB);                   \
 352        (INSN) != NEXT_INSN (BB_END (BB));       \
 353        (INSN) = NEXT_INSN (INSN))
 354
 355 #define FOR_BB_INSNS_REVERSE(BB, INSN)          \
 356   for ((INSN) = BB_END (BB);                    \
 357        (INSN) != PREV_INSN (BB_HEAD (BB));      \
 358        (INSN) = PREV_INSN (INSN))
 359
 360 /* Cycles through _all_ basic blocks, even the fake ones (entry and
 361    exit block).  */
 362
 363 #define FOR_ALL_BB(BB) \
 364   for (BB = ENTRY_BLOCK_PTR; BB; BB = BB->next_bb)
 365
 366 /* What registers are live at the setjmp call.  */
 367
 368 extern regset regs_live_at_setjmp;
 369
 370 /* Special labels found during CFG build.  */
 371
 372 extern GTY(()) rtx label_value_list;
 373
 374 extern struct obstack flow_obstack;
 375
 376 /* Indexed by n, gives number of basic block that  (REG n) is used in.
 377    If the value is REG_BLOCK_GLOBAL (-2),
 378    it means (REG n) is used in more than one basic block.
 379    REG_BLOCK_UNKNOWN (-1) means it hasn't been seen yet so we don't know.
 380    This information remains valid for the rest of the compilation
 381    of the current function; it is used to control register allocation.  */
 382
 383 #define REG_BLOCK_UNKNOWN -1
 384 #define REG_BLOCK_GLOBAL -2
 385
 386 #define REG_BASIC_BLOCK(N) (VARRAY_REG (reg_n_info, N)->basic_block)
 387 \f
 388 /* Stuff for recording basic block info.  */
 389
 390 #define BB_HEAD(B)      (B)->head_
 391 #define BB_END(B)       (B)->end_
 392
 393 /* Special block numbers [markers] for entry and exit.  */
 394 #define ENTRY_BLOCK (-1)
 395 #define EXIT_BLOCK (-2)
 396
 397 /* Special block number not valid for any block.  */
 398 #define INVALID_BLOCK (-3)
 399
 400 /* Similarly, block pointers for the edge list.  */
 401 extern GTY(()) basic_block ENTRY_BLOCK_PTR;
 402 extern GTY(()) basic_block EXIT_BLOCK_PTR;
 403
 404 #define BLOCK_NUM(INSN)       (BLOCK_FOR_INSN (INSN)->index + 0)
 405 #define set_block_for_insn(INSN, BB)  (BLOCK_FOR_INSN (INSN) = BB)
 406
 407 extern void compute_bb_for_insn (void);
 408 extern void free_bb_for_insn (void);
 409 extern void update_bb_for_insn (basic_block);
 410
 411 extern void free_basic_block_vars (void);
 412
 413 extern void insert_insn_on_edge (rtx, edge);
 414 bool safe_insert_insn_on_edge (rtx, edge);
 415
 416 extern void commit_edge_insertions (void);
 417 extern void commit_edge_insertions_watch_calls (void);
 418
 419 extern void remove_fake_edges (void);
 420 extern void add_noreturn_fake_exit_edges (void);
 421 extern void connect_infinite_loops_to_exit (void);
 422 extern edge unchecked_make_edge (basic_block, basic_block, int);
 423 extern edge cached_make_edge (sbitmap *, basic_block, basic_block, int);
 424 extern edge make_edge (basic_block, basic_block, int);
 425 extern edge make_single_succ_edge (basic_block, basic_block, int);
 426 extern void remove_edge (edge);
 427 extern void redirect_edge_succ (edge, basic_block);
 428 extern edge redirect_edge_succ_nodup (edge, basic_block);
 429 extern void redirect_edge_pred (edge, basic_block);
 430 extern basic_block create_basic_block_structure (rtx, rtx, rtx, basic_block);
 431 extern void clear_bb_flags (void);
 432 extern void flow_reverse_top_sort_order_compute (int *);
 433 extern int flow_depth_first_order_compute (int *, int *);
 434 extern void flow_preorder_transversal_compute (int *);
 435 extern int dfs_enumerate_from (basic_block, int,
 436                                bool (*)(basic_block, void *),
 437                                basic_block *, int, void *);
 438 extern void dump_edge_info (FILE *, edge, int);
 439 extern void brief_dump_cfg (FILE *);
 440 extern void clear_edges (void);
 441 extern void mark_critical_edges (void);
 442 extern rtx first_insn_after_basic_block_note (basic_block);
 443
 444 /* Structure to group all of the information to process IF-THEN and
 445    IF-THEN-ELSE blocks for the conditional execution support.  This
 446    needs to be in a public file in case the IFCVT macros call
 447    functions passing the ce_if_block data structure.  */
 448
 449 typedef struct ce_if_block
 450 {
 451   basic_block test_bb;                  /* First test block.  */
 452   basic_block then_bb;                  /* THEN block.  */
 453   basic_block else_bb;                  /* ELSE block or NULL.  */
 454   basic_block join_bb;                  /* Join THEN/ELSE blocks.  */
 455   basic_block last_test_bb;             /* Last bb to hold && or || tests.  */
 456   int num_multiple_test_blocks;         /* # of && and || basic blocks.  */
 457   int num_and_and_blocks;               /* # of && blocks.  */
 458   int num_or_or_blocks;                 /* # of || blocks.  */
 459   int num_multiple_test_insns;          /* # of insns in && and || blocks.  */
 460   int and_and_p;                        /* Complex test is &&.  */
 461   int num_then_insns;                   /* # of insns in THEN block.  */
 462   int num_else_insns;                   /* # of insns in ELSE block.  */
 463   int pass;                             /* Pass number.  */
 464
 465 #ifdef IFCVT_EXTRA_FIELDS
 466   IFCVT_EXTRA_FIELDS                    /* Any machine dependent fields.  */
 467 #endif
 468
 469 } ce_if_block_t;
 470
 471 /* This structure maintains an edge list vector.  */
 472 struct edge_list
 473 {
 474   int num_blocks;
 475   int num_edges;
 476   edge *index_to_edge;
 477 };
 478
 479 /* This is the value which indicates no edge is present.  */
 480 #define EDGE_INDEX_NO_EDGE      -1
 481
 482 /* EDGE_INDEX returns an integer index for an edge, or EDGE_INDEX_NO_EDGE
 483    if there is no edge between the 2 basic blocks.  */
 484 #define EDGE_INDEX(el, pred, succ) (find_edge_index ((el), (pred), (succ)))
 485
 486 /* INDEX_EDGE_PRED_BB and INDEX_EDGE_SUCC_BB return a pointer to the basic
 487    block which is either the pred or succ end of the indexed edge.  */
 488 #define INDEX_EDGE_PRED_BB(el, index)   ((el)->index_to_edge[(index)]->src)
 489 #define INDEX_EDGE_SUCC_BB(el, index)   ((el)->index_to_edge[(index)]->dest)
 490
 491 /* INDEX_EDGE returns a pointer to the edge.  */
 492 #define INDEX_EDGE(el, index)           ((el)->index_to_edge[(index)])
 493
 494 /* Number of edges in the compressed edge list.  */
 495 #define NUM_EDGES(el)                   ((el)->num_edges)
 496
 497 /* BB is assumed to contain conditional jump.  Return the fallthru edge.  */
 498 #define FALLTHRU_EDGE(bb)               ((bb)->succ->flags & EDGE_FALLTHRU \
 499                                          ? (bb)->succ : (bb)->succ->succ_next)
 500
 501 /* BB is assumed to contain conditional jump.  Return the branch edge.  */
 502 #define BRANCH_EDGE(bb)                 ((bb)->succ->flags & EDGE_FALLTHRU \
 503                                          ? (bb)->succ->succ_next : (bb)->succ)
 504
 505 /* Return expected execution frequency of the edge E.  */
 506 #define EDGE_FREQUENCY(e)               (((e)->src->frequency \
 507                                           * (e)->probability \
 508                                           + REG_BR_PROB_BASE / 2) \
 509                                          / REG_BR_PROB_BASE)
 510
 511 /* Return nonzero if edge is critical.  */
 512 #define EDGE_CRITICAL_P(e)              ((e)->src->succ->succ_next \
 513                                          && (e)->dest->pred->pred_next)
 514
 515 struct edge_list * create_edge_list (void);
 516 void free_edge_list (struct edge_list *);
 517 void print_edge_list (FILE *, struct edge_list *);
 518 void verify_edge_list (FILE *, struct edge_list *);
 519 int find_edge_index (struct edge_list *, basic_block, basic_block);
 520 edge find_edge (basic_block, basic_block);
 521
 522
 523 enum update_life_extent
 524 {
 525   UPDATE_LIFE_LOCAL = 0,
 526   UPDATE_LIFE_GLOBAL = 1,
 527   UPDATE_LIFE_GLOBAL_RM_NOTES = 2
 528 };
 529
 530 /* Flags for life_analysis and update_life_info.  */
 531
 532 #define PROP_DEATH_NOTES        1       /* Create DEAD and UNUSED notes.  */
 533 #define PROP_LOG_LINKS          2       /* Create LOG_LINKS.  */
 534 #define PROP_REG_INFO           4       /* Update regs_ever_live et al.  */
 535 #define PROP_KILL_DEAD_CODE     8       /* Remove dead code.  */
 536 #define PROP_SCAN_DEAD_CODE     16      /* Scan for dead code.  */
 537 #define PROP_ALLOW_CFG_CHANGES  32      /* Allow the CFG to be changed
 538                                            by dead code removal.  */
 539 #define PROP_AUTOINC            64      /* Create autoinc mem references.  */
 540 #define PROP_EQUAL_NOTES        128     /* Take into account REG_EQUAL notes.  */
 541 #define PROP_SCAN_DEAD_STORES   256     /* Scan for dead code.  */
 542 #define PROP_ASM_SCAN           512     /* Internal flag used within flow.c
 543                                            to flag analysis of asms.  */
 544 #define PROP_FINAL              (PROP_DEATH_NOTES | PROP_LOG_LINKS  \
 545                                  | PROP_REG_INFO | PROP_KILL_DEAD_CODE  \
 546                                  | PROP_SCAN_DEAD_CODE | PROP_AUTOINC \
 547                                  | PROP_ALLOW_CFG_CHANGES \
 548                                  | PROP_SCAN_DEAD_STORES)
 549 #define PROP_POSTRELOAD         (PROP_DEATH_NOTES  \
 550                                  | PROP_KILL_DEAD_CODE  \
 551                                  | PROP_SCAN_DEAD_CODE | PROP_AUTOINC \
 552                                  | PROP_SCAN_DEAD_STORES)
 553
 554 #define CLEANUP_EXPENSIVE       1       /* Do relatively expensive optimizations
 555                                            except for edge forwarding */
 556 #define CLEANUP_CROSSJUMP       2       /* Do crossjumping.  */
 557 #define CLEANUP_POST_REGSTACK   4       /* We run after reg-stack and need
 558                                            to care REG_DEAD notes.  */
 559 #define CLEANUP_PRE_LOOP        8       /* Take care to preserve syntactic loop
 560                                            notes.  */
 561 #define CLEANUP_UPDATE_LIFE     16      /* Keep life information up to date.  */
 562 #define CLEANUP_THREADING       32      /* Do jump threading.  */
 563 #define CLEANUP_NO_INSN_DEL     64      /* Do not try to delete trivially dead
 564                                            insns.  */
 565 #define CLEANUP_CFGLAYOUT       128     /* Do cleanup in cfglayout mode.  */
 566 #define CLEANUP_LOG_LINKS       256     /* Update log links.  */
 567
 568 extern void life_analysis (FILE *, int);
 569 extern int update_life_info (sbitmap, enum update_life_extent, int);
 570 extern int update_life_info_in_dirty_blocks (enum update_life_extent, int);
 571 extern int count_or_remove_death_notes (sbitmap, int);
 572 extern int propagate_block (basic_block, regset, regset, regset, int);
 573
 574 struct propagate_block_info;
 575 extern rtx propagate_one_insn (struct propagate_block_info *, rtx);
 576 extern struct propagate_block_info *init_propagate_block_info
 577  (basic_block, regset, regset, regset, int);
 578 extern void free_propagate_block_info (struct propagate_block_info *);
 579
 580 /* In lcm.c */
 581 extern struct edge_list *pre_edge_lcm (FILE *, int, sbitmap *, sbitmap *,
 582                                        sbitmap *, sbitmap *, sbitmap **,
 583                                        sbitmap **);
 584 extern struct edge_list *pre_edge_rev_lcm (FILE *, int, sbitmap *,
 585                                            sbitmap *, sbitmap *,
 586                                            sbitmap *, sbitmap **,
 587                                            sbitmap **);
 588 extern void compute_available (sbitmap *, sbitmap *, sbitmap *, sbitmap *);
 589 extern int optimize_mode_switching (FILE *);
 590
 591 /* In emit-rtl.c.  */
 592 extern rtx emit_block_insn_after (rtx, rtx, basic_block);
 593 extern rtx emit_block_insn_before (rtx, rtx, basic_block);
 594
 595 /* In predict.c */
 596 extern void estimate_probability (struct loops *);
 597 extern void note_prediction_to_br_prob (void);
 598 extern void expected_value_to_br_prob (void);
 599 extern bool maybe_hot_bb_p (basic_block);
 600 extern bool probably_cold_bb_p (basic_block);
 601 extern bool probably_never_executed_bb_p (basic_block);
 602 extern bool tree_predicted_by_p (basic_block, enum br_predictor);
 603 extern bool rtl_predicted_by_p (basic_block, enum br_predictor);
 604 extern void tree_predict_edge (edge, enum br_predictor, int);
 605 extern void rtl_predict_edge (edge, enum br_predictor, int);
 606 extern void predict_edge_def (edge, enum br_predictor, enum prediction);
 607
 608 /* In flow.c */
 609 extern void init_flow (void);
 610 extern void debug_bb (basic_block);
 611 extern basic_block debug_bb_n (int);
 612 extern void dump_regset (regset, FILE *);
 613 extern void debug_regset (regset);
 614 extern void allocate_reg_life_data (void);
 615 extern void allocate_bb_life_data (void);
 616 extern void expunge_block (basic_block);
 617 extern void link_block (basic_block, basic_block);
 618 extern void unlink_block (basic_block);
 619 extern void compact_blocks (void);
 620 extern basic_block alloc_block (void);
 621 extern void find_unreachable_blocks (void);
 622 extern int delete_noop_moves (void);
 623 extern basic_block force_nonfallthru (edge);
 624 extern rtx block_label (basic_block);
 625 extern bool forwarder_block_p (basic_block);
 626 extern bool purge_all_dead_edges (int);
 627 extern bool purge_dead_edges (basic_block);
 628 extern void find_sub_basic_blocks (basic_block);
 629 extern void find_many_sub_basic_blocks (sbitmap);
 630 extern void rtl_make_eh_edge (sbitmap *, basic_block, rtx);
 631 extern bool can_fallthru (basic_block, basic_block);
 632 extern void flow_nodes_print (const char *, const sbitmap, FILE *);
 633 extern void flow_edge_list_print (const char *, const edge *, int, FILE *);
 634 extern void alloc_aux_for_block (basic_block, int);
 635 extern void alloc_aux_for_blocks (int);
 636 extern void clear_aux_for_blocks (void);
 637 extern void free_aux_for_blocks (void);
 638 extern void alloc_aux_for_edge (edge, int);
 639 extern void alloc_aux_for_edges (int);
 640 extern void clear_aux_for_edges (void);
 641 extern void free_aux_for_edges (void);
 642 extern void find_basic_blocks (rtx, int, FILE *);
 643 extern bool cleanup_cfg (int);
 644 extern bool delete_unreachable_blocks (void);
 645 extern bool merge_seq_blocks (void);
 646
 647 typedef struct conflict_graph_def *conflict_graph;
 648
 649 /* Callback function when enumerating conflicts.  The arguments are
 650    the smaller and larger regno in the conflict.  Returns zero if
 651    enumeration is to continue, nonzero to halt enumeration.  */
 652 typedef int (*conflict_graph_enum_fn) (int, int, void *);
 653
 654
 655 /* Prototypes of operations on conflict graphs.  */
 656
 657 extern conflict_graph conflict_graph_new
 658  (int);
 659 extern void conflict_graph_delete (conflict_graph);
 660 extern int conflict_graph_add (conflict_graph, int, int);
 661 extern int conflict_graph_conflict_p (conflict_graph, int, int);
 662 extern void conflict_graph_enum (conflict_graph, int, conflict_graph_enum_fn,
 663                                  void *);
 664 extern void conflict_graph_merge_regs (conflict_graph, int, int);
 665 extern void conflict_graph_print (conflict_graph, FILE*);
 666 extern conflict_graph conflict_graph_compute (regset, partition);
 667 extern bool mark_dfs_back_edges (void);
 668 extern void set_edge_can_fallthru_flag (void);
 669 extern void update_br_prob_note (basic_block);
 670 extern void fixup_abnormal_edges (void);
 671 extern bool can_hoist_insn_p (rtx, rtx, regset);
 672 extern rtx hoist_insn_after (rtx, rtx, rtx, rtx);
 673 extern rtx hoist_insn_to_edge (rtx, edge, rtx, rtx);
 674 extern bool inside_basic_block_p (rtx);
 675 extern bool control_flow_insn_p (rtx);
 676
 677 /* In bb-reorder.c */
 678 extern void reorder_basic_blocks (void);
 679 extern void partition_hot_cold_basic_blocks (void);
 680
 681 /* In cfg.c */
 682 extern void alloc_rbi_pool (void);
 683 extern void initialize_bb_rbi (basic_block bb);
 684 extern void free_rbi_pool (void);
 685
 686 /* In dominance.c */
 687
 688 enum cdi_direction
 689 {
 690   CDI_DOMINATORS,
 691   CDI_POST_DOMINATORS
 692 };
 693
 694 enum dom_state
 695 {
 696   DOM_NONE,             /* Not computed at all.  */
 697   DOM_CONS_OK,          /* The data is conservatively OK, i.e. if it says you that A dominates B,
 698                            it indeed does.  */
 699   DOM_NO_FAST_QUERY,    /* The data is OK, but the fast query data are not usable.  */
 700   DOM_OK                /* Everything is ok.  */
 701 };
 702
 703 extern enum dom_state dom_computed[2];
 704
 705 extern void calculate_dominance_info (enum cdi_direction);
 706 extern void free_dominance_info (enum cdi_direction);
 707 extern basic_block nearest_common_dominator (enum cdi_direction,
 708                                              basic_block, basic_block);
 709 extern void set_immediate_dominator (enum cdi_direction, basic_block,
 710                                      basic_block);
 711 extern basic_block get_immediate_dominator (enum cdi_direction, basic_block);
 712 extern bool dominated_by_p (enum cdi_direction, basic_block, basic_block);
 713 extern int get_dominated_by (enum cdi_direction, basic_block, basic_block **);
 714 extern void add_to_dominance_info (enum cdi_direction, basic_block);
 715 extern void delete_from_dominance_info (enum cdi_direction, basic_block);
 716 basic_block recount_dominator (enum cdi_direction, basic_block);
 717 extern void redirect_immediate_dominators (enum cdi_direction, basic_block,
 718                                            basic_block);
 719 extern void iterate_fix_dominators (enum cdi_direction, basic_block *, int);
 720 extern void verify_dominators (enum cdi_direction);
 721 extern basic_block first_dom_son (enum cdi_direction, basic_block);
 722 extern basic_block next_dom_son (enum cdi_direction, basic_block);
 723 extern edge try_redirect_by_replacing_jump (edge, basic_block, bool);
 724 extern void break_superblocks (void);
 725
 726 #include "cfghooks.h"
 727
 728 #endif /* GCC_BASIC_BLOCK_H */