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 #include "vec.h"
  32 #include "errors.h"
  33
  34 /* Head of register set linked list.  */
  35 typedef bitmap_head regset_head;
  36
  37 /* A pointer to a regset_head.  */
  38 typedef bitmap regset;
  39
  40 /* Initialize a new regset.  */
  41 #define INIT_REG_SET(HEAD) bitmap_initialize (HEAD, 1)
  42
  43 /* Clear a register set by freeing up the linked list.  */
  44 #define CLEAR_REG_SET(HEAD) bitmap_clear (HEAD)
  45
  46 /* Copy a register set to another register set.  */
  47 #define COPY_REG_SET(TO, FROM) bitmap_copy (TO, FROM)
  48
  49 /* Compare two register sets.  */
  50 #define REG_SET_EQUAL_P(A, B) bitmap_equal_p (A, B)
  51
  52 /* `and' a register set with a second register set.  */
  53 #define AND_REG_SET(TO, FROM) bitmap_and_into (TO, FROM)
  54
  55 /* `and' the complement of a register set with a register set.  */
  56 #define AND_COMPL_REG_SET(TO, FROM) bitmap_and_compl_into (TO, FROM)
  57
  58 /* Inclusive or a register set with a second register set.  */
  59 #define IOR_REG_SET(TO, FROM) bitmap_ior_into (TO, FROM)
  60
  61 /* Exclusive or a register set with a second register set.  */
  62 #define XOR_REG_SET(TO, FROM) bitmap_xor_into (TO, FROM)
  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_into (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 (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 typedef bitmap_iterator reg_set_iterator;
  86
  87 /* Loop over all registers in REGSET, starting with MIN, setting REGNUM to the
  88    register number and executing CODE for all registers that are set.  */
  89 #define EXECUTE_IF_SET_IN_REG_SET(REGSET, MIN, REGNUM, RSI)     \
  90   EXECUTE_IF_SET_IN_BITMAP (REGSET, MIN, REGNUM, RSI)
  91
  92 /* Loop over all registers in REGSET1 and REGSET2, starting with MIN, setting
  93    REGNUM to the register number and executing CODE for all registers that are
  94    set in the first regset and not set in the second.  */
  95 #define EXECUTE_IF_AND_COMPL_IN_REG_SET(REGSET, MIN, REGNUM, RSI)       \
  96   EXECUTE_IF_AND_COMPL_IN_BITMAP (REGSET, MIN, REGNUM, RSI)
  97
  98 /* Loop over all registers in REGSET1 and REGSET2, starting with MIN, setting
  99    REGNUM to the register number and executing CODE for all registers that are
 100    set in both regsets.  */
 101 #define EXECUTE_IF_AND_IN_REG_SET(REGSET1, REGSET2, MIN, REGNUM, RSI) \
 102   EXECUTE_IF_AND_IN_BITMAP (REGSET1, REGSET2, MIN, REGNUM, RSI) \
 103
 104 /* Allocate a register set with oballoc.  */
 105 #define OBSTACK_ALLOC_REG_SET(OBSTACK) BITMAP_OBSTACK_ALLOC (OBSTACK)
 106
 107 /* Initialize a register set.  Returns the new register set.  */
 108 #define INITIALIZE_REG_SET(HEAD) bitmap_initialize (&HEAD, 1)
 109
 110 /* Do any cleanup needed on a regset when it is no longer used.  */
 111 #define FREE_REG_SET(REGSET) BITMAP_FREE(REGSET)
 112
 113 /* Do any one-time initializations needed for regsets.  */
 114 #define INIT_ONCE_REG_SET() BITMAP_INIT_ONCE ()
 115
 116 /* Grow any tables needed when the number of registers is calculated
 117    or extended.  For the linked list allocation, nothing needs to
 118    be done, other than zero the statistics on the first allocation.  */
 119 #define MAX_REGNO_REG_SET(NUM_REGS, NEW_P, RENUMBER_P)
 120
 121 /* Type we use to hold basic block counters.  Should be at least
 122    64bit.  Although a counter cannot be negative, we use a signed
 123    type, because erroneous negative counts can be generated when the
 124    flow graph is manipulated by various optimizations.  A signed type
 125    makes those easy to detect.  */
 126 typedef HOST_WIDEST_INT gcov_type;
 127
 128 /* Control flow edge information.  */
 129 struct edge_def GTY(())
 130 {
 131   /* The two blocks at the ends of the edge.  */
 132   struct basic_block_def *src;
 133   struct basic_block_def *dest;
 134
 135   /* Instructions queued on the edge.  */
 136   union edge_def_insns {
 137     rtx GTY ((tag ("0"))) r;
 138     tree GTY ((tag ("1"))) t;
 139   } GTY ((desc ("ir_type ()"))) insns;
 140
 141   /* Auxiliary info specific to a pass.  */
 142   PTR GTY ((skip (""))) aux;
 143
 144   /* Location of any goto implicit in the edge, during tree-ssa.  */
 145   source_locus goto_locus;
 146
 147   int flags;                    /* see EDGE_* below  */
 148   int probability;              /* biased by REG_BR_PROB_BASE */
 149   gcov_type count;              /* Expected number of executions calculated
 150                                    in profile.c  */
 151 };
 152
 153 typedef struct edge_def *edge;
 154 DEF_VEC_GC_P(edge);
 155
 156 #define EDGE_FALLTHRU           1       /* 'Straight line' flow */
 157 #define EDGE_ABNORMAL           2       /* Strange flow, like computed
 158                                            label, or eh */
 159 #define EDGE_ABNORMAL_CALL      4       /* Call with abnormal exit
 160                                            like an exception, or sibcall */
 161 #define EDGE_EH                 8       /* Exception throw */
 162 #define EDGE_FAKE               16      /* Not a real edge (profile.c) */
 163 #define EDGE_DFS_BACK           32      /* A backwards edge */
 164 #define EDGE_CAN_FALLTHRU       64      /* Candidate for straight line
 165                                            flow.  */
 166 #define EDGE_IRREDUCIBLE_LOOP   128     /* Part of irreducible loop.  */
 167 #define EDGE_SIBCALL            256     /* Edge from sibcall to exit.  */
 168 #define EDGE_LOOP_EXIT          512     /* Exit of a loop.  */
 169 #define EDGE_TRUE_VALUE         1024    /* Edge taken when controlling
 170                                            predicate is nonzero.  */
 171 #define EDGE_FALSE_VALUE        2048    /* Edge taken when controlling
 172                                            predicate is zero.  */
 173 #define EDGE_EXECUTABLE         4096    /* Edge is executable.  Only
 174                                            valid during SSA-CCP.  */
 175 #define EDGE_CROSSING           8192    /* Edge crosses between hot
 176                                            and cold sections, when we
 177                                            do partitioning.  */
 178 #define EDGE_ALL_FLAGS         16383
 179
 180 #define EDGE_COMPLEX    (EDGE_ABNORMAL | EDGE_ABNORMAL_CALL | EDGE_EH)
 181
 182 /* Counter summary from the last set of coverage counts read by
 183    profile.c.  */
 184 extern const struct gcov_ctr_summary *profile_info;
 185
 186 /* Declared in cfgloop.h.  */
 187 struct loop;
 188 struct loops;
 189
 190 /* Declared in tree-flow.h.  */
 191 struct bb_ann_d;
 192
 193 /* A basic block is a sequence of instructions with only entry and
 194    only one exit.  If any one of the instructions are executed, they
 195    will all be executed, and in sequence from first to last.
 196
 197    There may be COND_EXEC instructions in the basic block.  The
 198    COND_EXEC *instructions* will be executed -- but if the condition
 199    is false the conditionally executed *expressions* will of course
 200    not be executed.  We don't consider the conditionally executed
 201    expression (which might have side-effects) to be in a separate
 202    basic block because the program counter will always be at the same
 203    location after the COND_EXEC instruction, regardless of whether the
 204    condition is true or not.
 205
 206    Basic blocks need not start with a label nor end with a jump insn.
 207    For example, a previous basic block may just "conditionally fall"
 208    into the succeeding basic block, and the last basic block need not
 209    end with a jump insn.  Block 0 is a descendant of the entry block.
 210
 211    A basic block beginning with two labels cannot have notes between
 212    the labels.
 213
 214    Data for jump tables are stored in jump_insns that occur in no
 215    basic block even though these insns can follow or precede insns in
 216    basic blocks.  */
 217
 218 /* Basic block information indexed by block number.  */
 219 struct basic_block_def GTY((chain_next ("%h.next_bb"), chain_prev ("%h.prev_bb")))
 220 {
 221   /* The first and last insns of the block.  */
 222   rtx head_;
 223   rtx end_;
 224
 225   /* Pointers to the first and last trees of the block.  */
 226   tree stmt_list;
 227
 228   /* The edges into and out of the block.  */
 229   VEC(edge) *preds;
 230   VEC(edge) *succs;
 231
 232   /* Liveness info.  */
 233
 234   /* The registers that are modified within this in block.  */
 235   bitmap GTY ((skip (""))) local_set;
 236   /* The registers that are conditionally modified within this block.
 237      In other words, registers that are set only as part of a
 238      COND_EXEC.  */
 239   bitmap GTY ((skip (""))) cond_local_set;
 240   /* The registers that are live on entry to this block.
 241
 242      Note that in SSA form, global_live_at_start does not reflect the
 243      use of regs in phi functions, since the liveness of these regs
 244      may depend on which edge was taken into the block.  */
 245   bitmap GTY ((skip (""))) global_live_at_start;
 246   /* The registers that are live on exit from this block.  */
 247   bitmap GTY ((skip (""))) global_live_at_end;
 248
 249   /* Auxiliary info specific to a pass.  */
 250   PTR GTY ((skip (""))) aux;
 251
 252   /* Innermost loop containing the block.  */
 253   struct loop * GTY ((skip (""))) loop_father;
 254
 255   /* The dominance and postdominance information node.  */
 256   struct et_node * GTY ((skip (""))) dom[2];
 257
 258   /* Previous and next blocks in the chain.  */
 259   struct basic_block_def *prev_bb;
 260   struct basic_block_def *next_bb;
 261
 262   /* The data used by basic block copying and reordering functions.  */
 263   struct reorder_block_def * GTY ((skip (""))) rbi;
 264
 265   /* Annotations used at the tree level.  */
 266   struct bb_ann_d *tree_annotations;
 267
 268   /* Expected number of executions: calculated in profile.c.  */
 269   gcov_type count;
 270
 271   /* The index of this block.  */
 272   int index;
 273
 274   /* The loop depth of this block.  */
 275   int loop_depth;
 276
 277   /* Expected frequency.  Normalized to be in range 0 to BB_FREQ_MAX.  */
 278   int frequency;
 279
 280   /* Various flags.  See BB_* below.  */
 281   int flags;
 282 };
 283
 284 typedef struct basic_block_def *basic_block;
 285
 286 /* Structure to hold information about the blocks during reordering and
 287    copying.  */
 288
 289 typedef struct reorder_block_def
 290 {
 291   rtx header;
 292   rtx footer;
 293   basic_block next;
 294   basic_block original;
 295   /* Used by loop copying.  */
 296   basic_block copy;
 297   int duplicated;
 298   int copy_number;
 299
 300   /* These fields are used by bb-reorder pass.  */
 301   int visited;
 302 } *reorder_block_def_p;
 303
 304 #define BB_FREQ_MAX 10000
 305
 306 /* Masks for basic_block.flags.  */
 307 #define BB_DIRTY                1
 308 #define BB_NEW                  2
 309 #define BB_REACHABLE            4
 310 #define BB_VISITED              8
 311 #define BB_IRREDUCIBLE_LOOP     16
 312 #define BB_SUPERBLOCK           32
 313 #define BB_DISABLE_SCHEDULE     64
 314
 315 #define BB_HOT_PARTITION        128
 316 #define BB_COLD_PARTITION       256
 317 #define BB_UNPARTITIONED        0
 318
 319 /* Partitions, to be used when partitioning hot and cold basic blocks into
 320    separate sections.  */
 321 #define BB_PARTITION(bb) ((bb)->flags & (BB_HOT_PARTITION|BB_COLD_PARTITION))
 322 #define BB_SET_PARTITION(bb, part) do {                                 \
 323   basic_block bb_ = (bb);                                               \
 324   bb_->flags = ((bb_->flags & ~(BB_HOT_PARTITION|BB_COLD_PARTITION))    \
 325                 | (part));                                              \
 326 } while (0)
 327
 328 #define BB_COPY_PARTITION(dstbb, srcbb) \
 329   BB_SET_PARTITION (dstbb, BB_PARTITION (srcbb))
 330
 331 /* Number of basic blocks in the current function.  */
 332
 333 extern int n_basic_blocks;
 334
 335 /* First free basic block number.  */
 336
 337 extern int last_basic_block;
 338
 339 /* Number of edges in the current function.  */
 340
 341 extern int n_edges;
 342
 343 /* Signalize the status of profile information in the CFG.  */
 344 extern enum profile_status
 345 {
 346   PROFILE_ABSENT,
 347   PROFILE_GUESSED,
 348   PROFILE_READ
 349 } profile_status;
 350
 351 /* Index by basic block number, get basic block struct info.  */
 352
 353 extern GTY(()) varray_type basic_block_info;
 354
 355 #define BASIC_BLOCK(N)  (VARRAY_BB (basic_block_info, (N)))
 356
 357 /* For iterating over basic blocks.  */
 358 #define FOR_BB_BETWEEN(BB, FROM, TO, DIR) \
 359   for (BB = FROM; BB != TO; BB = BB->DIR)
 360
 361 #define FOR_EACH_BB(BB) \
 362   FOR_BB_BETWEEN (BB, ENTRY_BLOCK_PTR->next_bb, EXIT_BLOCK_PTR, next_bb)
 363
 364 #define FOR_EACH_BB_REVERSE(BB) \
 365   FOR_BB_BETWEEN (BB, EXIT_BLOCK_PTR->prev_bb, ENTRY_BLOCK_PTR, prev_bb)
 366
 367 /* For iterating over insns in basic block.  */
 368 #define FOR_BB_INSNS(BB, INSN)                  \
 369   for ((INSN) = BB_HEAD (BB);                   \
 370        (INSN) != NEXT_INSN (BB_END (BB));       \
 371        (INSN) = NEXT_INSN (INSN))
 372
 373 #define FOR_BB_INSNS_REVERSE(BB, INSN)          \
 374   for ((INSN) = BB_END (BB);                    \
 375        (INSN) != PREV_INSN (BB_HEAD (BB));      \
 376        (INSN) = PREV_INSN (INSN))
 377
 378 /* Cycles through _all_ basic blocks, even the fake ones (entry and
 379    exit block).  */
 380
 381 #define FOR_ALL_BB(BB) \
 382   for (BB = ENTRY_BLOCK_PTR; BB; BB = BB->next_bb)
 383
 384 /* What registers are live at the setjmp call.  */
 385
 386 extern regset regs_live_at_setjmp;
 387
 388 /* Special labels found during CFG build.  */
 389
 390 extern GTY(()) rtx label_value_list;
 391
 392 extern struct obstack flow_obstack;
 393
 394 /* Indexed by n, gives number of basic block that  (REG n) is used in.
 395    If the value is REG_BLOCK_GLOBAL (-2),
 396    it means (REG n) is used in more than one basic block.
 397    REG_BLOCK_UNKNOWN (-1) means it hasn't been seen yet so we don't know.
 398    This information remains valid for the rest of the compilation
 399    of the current function; it is used to control register allocation.  */
 400
 401 #define REG_BLOCK_UNKNOWN -1
 402 #define REG_BLOCK_GLOBAL -2
 403
 404 #define REG_BASIC_BLOCK(N) (VARRAY_REG (reg_n_info, N)->basic_block)
 405 \f
 406 /* Stuff for recording basic block info.  */
 407
 408 #define BB_HEAD(B)      (B)->head_
 409 #define BB_END(B)       (B)->end_
 410
 411 /* Special block numbers [markers] for entry and exit.  */
 412 #define ENTRY_BLOCK (-1)
 413 #define EXIT_BLOCK (-2)
 414
 415 /* Special block number not valid for any block.  */
 416 #define INVALID_BLOCK (-3)
 417
 418 /* Similarly, block pointers for the edge list.  */
 419 extern GTY(()) basic_block ENTRY_BLOCK_PTR;
 420 extern GTY(()) basic_block EXIT_BLOCK_PTR;
 421
 422 #define BLOCK_NUM(INSN)       (BLOCK_FOR_INSN (INSN)->index + 0)
 423 #define set_block_for_insn(INSN, BB)  (BLOCK_FOR_INSN (INSN) = BB)
 424
 425 extern void compute_bb_for_insn (void);
 426 extern void free_bb_for_insn (void);
 427 extern void update_bb_for_insn (basic_block);
 428
 429 extern void free_basic_block_vars (void);
 430
 431 extern void insert_insn_on_edge (rtx, edge);
 432 bool safe_insert_insn_on_edge (rtx, edge);
 433
 434 extern void commit_edge_insertions (void);
 435 extern void commit_edge_insertions_watch_calls (void);
 436
 437 extern void remove_fake_edges (void);
 438 extern void remove_fake_exit_edges (void);
 439 extern void add_noreturn_fake_exit_edges (void);
 440 extern void connect_infinite_loops_to_exit (void);
 441 extern edge unchecked_make_edge (basic_block, basic_block, int);
 442 extern edge cached_make_edge (sbitmap *, basic_block, basic_block, int);
 443 extern edge make_edge (basic_block, basic_block, int);
 444 extern edge make_single_succ_edge (basic_block, basic_block, int);
 445 extern void remove_edge (edge);
 446 extern void redirect_edge_succ (edge, basic_block);
 447 extern edge redirect_edge_succ_nodup (edge, basic_block);
 448 extern void redirect_edge_pred (edge, basic_block);
 449 extern basic_block create_basic_block_structure (rtx, rtx, rtx, basic_block);
 450 extern void clear_bb_flags (void);
 451 extern void flow_reverse_top_sort_order_compute (int *);
 452 extern int flow_depth_first_order_compute (int *, int *);
 453 extern int dfs_enumerate_from (basic_block, int,
 454                                bool (*)(basic_block, void *),
 455                                basic_block *, int, void *);
 456 extern void compute_dominance_frontiers (bitmap *);
 457 extern void dump_edge_info (FILE *, edge, int);
 458 extern void brief_dump_cfg (FILE *);
 459 extern void clear_edges (void);
 460 extern void mark_critical_edges (void);
 461 extern rtx first_insn_after_basic_block_note (basic_block);
 462
 463 /* Structure to group all of the information to process IF-THEN and
 464    IF-THEN-ELSE blocks for the conditional execution support.  This
 465    needs to be in a public file in case the IFCVT macros call
 466    functions passing the ce_if_block data structure.  */
 467
 468 typedef struct ce_if_block
 469 {
 470   basic_block test_bb;                  /* First test block.  */
 471   basic_block then_bb;                  /* THEN block.  */
 472   basic_block else_bb;                  /* ELSE block or NULL.  */
 473   basic_block join_bb;                  /* Join THEN/ELSE blocks.  */
 474   basic_block last_test_bb;             /* Last bb to hold && or || tests.  */
 475   int num_multiple_test_blocks;         /* # of && and || basic blocks.  */
 476   int num_and_and_blocks;               /* # of && blocks.  */
 477   int num_or_or_blocks;                 /* # of || blocks.  */
 478   int num_multiple_test_insns;          /* # of insns in && and || blocks.  */
 479   int and_and_p;                        /* Complex test is &&.  */
 480   int num_then_insns;                   /* # of insns in THEN block.  */
 481   int num_else_insns;                   /* # of insns in ELSE block.  */
 482   int pass;                             /* Pass number.  */
 483
 484 #ifdef IFCVT_EXTRA_FIELDS
 485   IFCVT_EXTRA_FIELDS                    /* Any machine dependent fields.  */
 486 #endif
 487
 488 } ce_if_block_t;
 489
 490 /* This structure maintains an edge list vector.  */
 491 struct edge_list
 492 {
 493   int num_blocks;
 494   int num_edges;
 495   edge *index_to_edge;
 496 };
 497
 498 /* This is the value which indicates no edge is present.  */
 499 #define EDGE_INDEX_NO_EDGE      -1
 500
 501 /* EDGE_INDEX returns an integer index for an edge, or EDGE_INDEX_NO_EDGE
 502    if there is no edge between the 2 basic blocks.  */
 503 #define EDGE_INDEX(el, pred, succ) (find_edge_index ((el), (pred), (succ)))
 504
 505 /* INDEX_EDGE_PRED_BB and INDEX_EDGE_SUCC_BB return a pointer to the basic
 506    block which is either the pred or succ end of the indexed edge.  */
 507 #define INDEX_EDGE_PRED_BB(el, index)   ((el)->index_to_edge[(index)]->src)
 508 #define INDEX_EDGE_SUCC_BB(el, index)   ((el)->index_to_edge[(index)]->dest)
 509
 510 /* INDEX_EDGE returns a pointer to the edge.  */
 511 #define INDEX_EDGE(el, index)           ((el)->index_to_edge[(index)])
 512
 513 /* Number of edges in the compressed edge list.  */
 514 #define NUM_EDGES(el)                   ((el)->num_edges)
 515
 516 /* BB is assumed to contain conditional jump.  Return the fallthru edge.  */
 517 #define FALLTHRU_EDGE(bb)               (EDGE_SUCC ((bb), 0)->flags & EDGE_FALLTHRU \
 518                                          ? EDGE_SUCC ((bb), 0) : EDGE_SUCC ((bb), 1))
 519
 520 /* BB is assumed to contain conditional jump.  Return the branch edge.  */
 521 #define BRANCH_EDGE(bb)                 (EDGE_SUCC ((bb), 0)->flags & EDGE_FALLTHRU \
 522                                          ? EDGE_SUCC ((bb), 1) : EDGE_SUCC ((bb), 0))
 523
 524 /* Return expected execution frequency of the edge E.  */
 525 #define EDGE_FREQUENCY(e)               (((e)->src->frequency \
 526                                           * (e)->probability \
 527                                           + REG_BR_PROB_BASE / 2) \
 528                                          / REG_BR_PROB_BASE)
 529
 530 /* Return nonzero if edge is critical.  */
 531 #define EDGE_CRITICAL_P(e)              (EDGE_COUNT ((e)->src->succs) >= 2 \
 532                                          && EDGE_COUNT ((e)->dest->preds) >= 2)
 533
 534 #define EDGE_COUNT(ev)                  VEC_length (edge, (ev))
 535 #define EDGE_I(ev,i)                    VEC_index  (edge, (ev), (i))
 536 #define EDGE_PRED(bb,i)                 VEC_index  (edge, (bb)->preds, (i))
 537 #define EDGE_SUCC(bb,i)                 VEC_index  (edge, (bb)->succs, (i))
 538
 539 /* Iterator object for edges.  */
 540
 541 typedef struct {
 542   unsigned index;
 543   VEC(edge) **container;
 544 } edge_iterator;
 545
 546 static inline VEC(edge) *
 547 ei_container (edge_iterator i)
 548 {
 549   gcc_assert (i.container);
 550   return *i.container;
 551 }
 552
 553 #define ei_start(iter) ei_start_1 (&(iter))
 554 #define ei_last(iter) ei_last_1 (&(iter))
 555
 556 /* Return an iterator pointing to the start of an edge vector.  */
 557 static inline edge_iterator
 558 ei_start_1 (VEC(edge) **ev)
 559 {
 560   edge_iterator i;
 561
 562   i.index = 0;
 563   i.container = ev;
 564
 565   return i;
 566 }
 567
 568 /* Return an iterator pointing to the last element of an edge
 569    vector.  */
 570 static inline edge_iterator
 571 ei_last_1 (VEC(edge) **ev)
 572 {
 573   edge_iterator i;
 574
 575   i.index = EDGE_COUNT (*ev) - 1;
 576   i.container = ev;
 577
 578   return i;
 579 }
 580
 581 /* Is the iterator `i' at the end of the sequence?  */
 582 static inline bool
 583 ei_end_p (edge_iterator i)
 584 {
 585   return (i.index == EDGE_COUNT (ei_container (i)));
 586 }
 587
 588 /* Is the iterator `i' at one position before the end of the
 589    sequence?  */
 590 static inline bool
 591 ei_one_before_end_p (edge_iterator i)
 592 {
 593   return (i.index + 1 == EDGE_COUNT (ei_container (i)));
 594 }
 595
 596 /* Advance the iterator to the next element.  */
 597 static inline void
 598 ei_next (edge_iterator *i)
 599 {
 600   gcc_assert (i->index < EDGE_COUNT (ei_container (*i)));
 601   i->index++;
 602 }
 603
 604 /* Move the iterator to the previous element.  */
 605 static inline void
 606 ei_prev (edge_iterator *i)
 607 {
 608   gcc_assert (i->index > 0);
 609   i->index--;
 610 }
 611
 612 /* Return the edge pointed to by the iterator `i'.  */
 613 static inline edge
 614 ei_edge (edge_iterator i)
 615 {
 616   return EDGE_I (ei_container (i), i.index);
 617 }
 618
 619 /* Return an edge pointed to by the iterator.  Do it safely so that
 620    NULL is returned when the iterator is pointing at the end of the
 621    sequence.  */
 622 static inline edge
 623 ei_safe_edge (edge_iterator i)
 624 {
 625   return !ei_end_p (i) ? ei_edge (i) : NULL;
 626 }
 627
 628 /* This macro serves as a convenient way to iterate each edge in a
 629    vector of predecessor or successor edges.  It must not be used when
 630    an element might be removed during the traversal, otherwise
 631    elements will be missed.  Instead, use a for-loop like that shown
 632    in the following pseudo-code:
 633
 634    FOR (ei = ei_start (bb->succs); (e = ei_safe_edge (ei)); )
 635      {
 636         IF (e != taken_edge)
 637           ssa_remove_edge (e);
 638         ELSE
 639           ei_next (&ei);
 640      }
 641 */
 642
 643 #define FOR_EACH_EDGE(EDGE,ITER,EDGE_VEC) \
 644   for ((EDGE) = NULL, (ITER) = ei_start ((EDGE_VEC)); \
 645        ((EDGE) = ei_safe_edge ((ITER))); \
 646        ei_next (&(ITER)))
 647
 648 struct edge_list * create_edge_list (void);
 649 void free_edge_list (struct edge_list *);
 650 void print_edge_list (FILE *, struct edge_list *);
 651 void verify_edge_list (FILE *, struct edge_list *);
 652 int find_edge_index (struct edge_list *, basic_block, basic_block);
 653 edge find_edge (basic_block, basic_block);
 654
 655
 656 enum update_life_extent
 657 {
 658   UPDATE_LIFE_LOCAL = 0,
 659   UPDATE_LIFE_GLOBAL = 1,
 660   UPDATE_LIFE_GLOBAL_RM_NOTES = 2
 661 };
 662
 663 /* Flags for life_analysis and update_life_info.  */
 664
 665 #define PROP_DEATH_NOTES        1       /* Create DEAD and UNUSED notes.  */
 666 #define PROP_LOG_LINKS          2       /* Create LOG_LINKS.  */
 667 #define PROP_REG_INFO           4       /* Update regs_ever_live et al.  */
 668 #define PROP_KILL_DEAD_CODE     8       /* Remove dead code.  */
 669 #define PROP_SCAN_DEAD_CODE     16      /* Scan for dead code.  */
 670 #define PROP_ALLOW_CFG_CHANGES  32      /* Allow the CFG to be changed
 671                                            by dead code removal.  */
 672 #define PROP_AUTOINC            64      /* Create autoinc mem references.  */
 673 #define PROP_EQUAL_NOTES        128     /* Take into account REG_EQUAL notes.  */
 674 #define PROP_SCAN_DEAD_STORES   256     /* Scan for dead code.  */
 675 #define PROP_ASM_SCAN           512     /* Internal flag used within flow.c
 676                                            to flag analysis of asms.  */
 677 #define PROP_FINAL              (PROP_DEATH_NOTES | PROP_LOG_LINKS  \
 678                                  | PROP_REG_INFO | PROP_KILL_DEAD_CODE  \
 679                                  | PROP_SCAN_DEAD_CODE | PROP_AUTOINC \
 680                                  | PROP_ALLOW_CFG_CHANGES \
 681                                  | PROP_SCAN_DEAD_STORES)
 682 #define PROP_POSTRELOAD         (PROP_DEATH_NOTES  \
 683                                  | PROP_KILL_DEAD_CODE  \
 684                                  | PROP_SCAN_DEAD_CODE | PROP_AUTOINC \
 685                                  | PROP_SCAN_DEAD_STORES)
 686
 687 #define CLEANUP_EXPENSIVE       1       /* Do relatively expensive optimizations
 688                                            except for edge forwarding */
 689 #define CLEANUP_CROSSJUMP       2       /* Do crossjumping.  */
 690 #define CLEANUP_POST_REGSTACK   4       /* We run after reg-stack and need
 691                                            to care REG_DEAD notes.  */
 692 #define CLEANUP_PRE_LOOP        8       /* Take care to preserve syntactic loop
 693                                            notes.  */
 694 #define CLEANUP_UPDATE_LIFE     16      /* Keep life information up to date.  */
 695 #define CLEANUP_THREADING       32      /* Do jump threading.  */
 696 #define CLEANUP_NO_INSN_DEL     64      /* Do not try to delete trivially dead
 697                                            insns.  */
 698 #define CLEANUP_CFGLAYOUT       128     /* Do cleanup in cfglayout mode.  */
 699 #define CLEANUP_LOG_LINKS       256     /* Update log links.  */
 700
 701 extern void life_analysis (FILE *, int);
 702 extern int update_life_info (sbitmap, enum update_life_extent, int);
 703 extern int update_life_info_in_dirty_blocks (enum update_life_extent, int);
 704 extern int count_or_remove_death_notes (sbitmap, int);
 705 extern int propagate_block (basic_block, regset, regset, regset, int);
 706
 707 struct propagate_block_info;
 708 extern rtx propagate_one_insn (struct propagate_block_info *, rtx);
 709 extern struct propagate_block_info *init_propagate_block_info
 710  (basic_block, regset, regset, regset, int);
 711 extern void free_propagate_block_info (struct propagate_block_info *);
 712
 713 /* In lcm.c */
 714 extern struct edge_list *pre_edge_lcm (FILE *, int, sbitmap *, sbitmap *,
 715                                        sbitmap *, sbitmap *, sbitmap **,
 716                                        sbitmap **);
 717 extern struct edge_list *pre_edge_rev_lcm (FILE *, int, sbitmap *,
 718                                            sbitmap *, sbitmap *,
 719                                            sbitmap *, sbitmap **,
 720                                            sbitmap **);
 721 extern void compute_available (sbitmap *, sbitmap *, sbitmap *, sbitmap *);
 722 extern int optimize_mode_switching (FILE *);
 723
 724 /* In emit-rtl.c.  */
 725 extern rtx emit_block_insn_after (rtx, rtx, basic_block);
 726 extern rtx emit_block_insn_before (rtx, rtx, basic_block);
 727
 728 /* In predict.c */
 729 extern void estimate_probability (struct loops *);
 730 extern void expected_value_to_br_prob (void);
 731 extern bool maybe_hot_bb_p (basic_block);
 732 extern bool probably_cold_bb_p (basic_block);
 733 extern bool probably_never_executed_bb_p (basic_block);
 734 extern bool tree_predicted_by_p (basic_block, enum br_predictor);
 735 extern bool rtl_predicted_by_p (basic_block, enum br_predictor);
 736 extern void tree_predict_edge (edge, enum br_predictor, int);
 737 extern void rtl_predict_edge (edge, enum br_predictor, int);
 738 extern void predict_edge_def (edge, enum br_predictor, enum prediction);
 739 extern void guess_outgoing_edge_probabilities (basic_block);
 740
 741 /* In flow.c */
 742 extern void init_flow (void);
 743 extern void debug_bb (basic_block);
 744 extern basic_block debug_bb_n (int);
 745 extern void dump_regset (regset, FILE *);
 746 extern void debug_regset (regset);
 747 extern void allocate_reg_life_data (void);
 748 extern void allocate_bb_life_data (void);
 749 extern void expunge_block (basic_block);
 750 extern void link_block (basic_block, basic_block);
 751 extern void unlink_block (basic_block);
 752 extern void compact_blocks (void);
 753 extern basic_block alloc_block (void);
 754 extern void find_unreachable_blocks (void);
 755 extern int delete_noop_moves (void);
 756 extern basic_block force_nonfallthru (edge);
 757 extern rtx block_label (basic_block);
 758 extern bool forwarder_block_p (basic_block);
 759 extern bool purge_all_dead_edges (int);
 760 extern bool purge_dead_edges (basic_block);
 761 extern void find_sub_basic_blocks (basic_block);
 762 extern void find_many_sub_basic_blocks (sbitmap);
 763 extern void rtl_make_eh_edge (sbitmap *, basic_block, rtx);
 764 extern bool can_fallthru (basic_block, basic_block);
 765 extern bool could_fall_through (basic_block, basic_block);
 766 extern void flow_nodes_print (const char *, const sbitmap, FILE *);
 767 extern void flow_edge_list_print (const char *, const edge *, int, FILE *);
 768 extern void alloc_aux_for_block (basic_block, int);
 769 extern void alloc_aux_for_blocks (int);
 770 extern void clear_aux_for_blocks (void);
 771 extern void free_aux_for_blocks (void);
 772 extern void alloc_aux_for_edge (edge, int);
 773 extern void alloc_aux_for_edges (int);
 774 extern void clear_aux_for_edges (void);
 775 extern void free_aux_for_edges (void);
 776 extern void find_basic_blocks (rtx, int, FILE *);
 777 extern bool cleanup_cfg (int);
 778 extern bool delete_unreachable_blocks (void);
 779 extern bool merge_seq_blocks (void);
 780
 781 typedef struct conflict_graph_def *conflict_graph;
 782
 783 /* Callback function when enumerating conflicts.  The arguments are
 784    the smaller and larger regno in the conflict.  Returns zero if
 785    enumeration is to continue, nonzero to halt enumeration.  */
 786 typedef int (*conflict_graph_enum_fn) (int, int, void *);
 787
 788
 789 /* Prototypes of operations on conflict graphs.  */
 790
 791 extern conflict_graph conflict_graph_new
 792  (int);
 793 extern void conflict_graph_delete (conflict_graph);
 794 extern int conflict_graph_add (conflict_graph, int, int);
 795 extern int conflict_graph_conflict_p (conflict_graph, int, int);
 796 extern void conflict_graph_enum (conflict_graph, int, conflict_graph_enum_fn,
 797                                  void *);
 798 extern void conflict_graph_merge_regs (conflict_graph, int, int);
 799 extern void conflict_graph_print (conflict_graph, FILE*);
 800 extern conflict_graph conflict_graph_compute (regset, partition);
 801 extern bool mark_dfs_back_edges (void);
 802 extern void set_edge_can_fallthru_flag (void);
 803 extern void update_br_prob_note (basic_block);
 804 extern void fixup_abnormal_edges (void);
 805 extern bool inside_basic_block_p (rtx);
 806 extern bool control_flow_insn_p (rtx);
 807
 808 /* In bb-reorder.c */
 809 extern void reorder_basic_blocks (unsigned int);
 810 extern void partition_hot_cold_basic_blocks (void);
 811
 812 /* In cfg.c */
 813 extern void alloc_rbi_pool (void);
 814 extern void initialize_bb_rbi (basic_block bb);
 815 extern void free_rbi_pool (void);
 816
 817 /* In dominance.c */
 818
 819 enum cdi_direction
 820 {
 821   CDI_DOMINATORS,
 822   CDI_POST_DOMINATORS
 823 };
 824
 825 enum dom_state
 826 {
 827   DOM_NONE,             /* Not computed at all.  */
 828   DOM_NO_FAST_QUERY,    /* The data is OK, but the fast query data are not usable.  */
 829   DOM_OK                /* Everything is ok.  */
 830 };
 831
 832 extern enum dom_state dom_computed[2];
 833
 834 extern bool dom_info_available_p (enum cdi_direction);
 835 extern void calculate_dominance_info (enum cdi_direction);
 836 extern void free_dominance_info (enum cdi_direction);
 837 extern basic_block nearest_common_dominator (enum cdi_direction,
 838                                              basic_block, basic_block);
 839 extern void set_immediate_dominator (enum cdi_direction, basic_block,
 840                                      basic_block);
 841 extern basic_block get_immediate_dominator (enum cdi_direction, basic_block);
 842 extern bool dominated_by_p (enum cdi_direction, basic_block, basic_block);
 843 extern int get_dominated_by (enum cdi_direction, basic_block, basic_block **);
 844 extern unsigned get_dominated_by_region (enum cdi_direction, basic_block *,
 845                                          unsigned, basic_block *);
 846 extern void add_to_dominance_info (enum cdi_direction, basic_block);
 847 extern void delete_from_dominance_info (enum cdi_direction, basic_block);
 848 basic_block recount_dominator (enum cdi_direction, basic_block);
 849 extern void redirect_immediate_dominators (enum cdi_direction, basic_block,
 850                                            basic_block);
 851 extern void iterate_fix_dominators (enum cdi_direction, basic_block *, int);
 852 extern void verify_dominators (enum cdi_direction);
 853 extern basic_block first_dom_son (enum cdi_direction, basic_block);
 854 extern basic_block next_dom_son (enum cdi_direction, basic_block);
 855 extern edge try_redirect_by_replacing_jump (edge, basic_block, bool);
 856 extern void break_superblocks (void);
 857 extern void check_bb_profile (basic_block, FILE *);
 858 extern void update_bb_profile_for_threading (basic_block, int, gcov_type, edge);
 859
 860 #include "cfghooks.h"
 861
 862 #endif /* GCC_BASIC_BLOCK_H */