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    2005, 2006, 2007, 2008 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 3, 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 COPYING3.  If not see
  19 <http://www.gnu.org/licenses/>.  */
  20
  21 #ifndef GCC_BASIC_BLOCK_H
  22 #define GCC_BASIC_BLOCK_H
  23
  24 #include "bitmap.h"
  25 #include "sbitmap.h"
  26 #include "varray.h"
  27 #include "partition.h"
  28 #include "hard-reg-set.h"
  29 #include "predict.h"
  30 #include "vec.h"
  31 #include "function.h"
  32
  33 /* Head of register set linked list.  */
  34 typedef bitmap_head regset_head;
  35
  36 /* A pointer to a regset_head.  */
  37 typedef bitmap regset;
  38
  39 /* Allocate a register set with oballoc.  */
  40 #define ALLOC_REG_SET(OBSTACK) BITMAP_ALLOC (OBSTACK)
  41
  42 /* Do any cleanup needed on a regset when it is no longer used.  */
  43 #define FREE_REG_SET(REGSET) BITMAP_FREE (REGSET)
  44
  45 /* Initialize a new regset.  */
  46 #define INIT_REG_SET(HEAD) bitmap_initialize (HEAD, &reg_obstack)
  47
  48 /* Clear a register set by freeing up the linked list.  */
  49 #define CLEAR_REG_SET(HEAD) bitmap_clear (HEAD)
  50
  51 /* Copy a register set to another register set.  */
  52 #define COPY_REG_SET(TO, FROM) bitmap_copy (TO, FROM)
  53
  54 /* Compare two register sets.  */
  55 #define REG_SET_EQUAL_P(A, B) bitmap_equal_p (A, B)
  56
  57 /* `and' a register set with a second register set.  */
  58 #define AND_REG_SET(TO, FROM) bitmap_and_into (TO, FROM)
  59
  60 /* `and' the complement of a register set with a register set.  */
  61 #define AND_COMPL_REG_SET(TO, FROM) bitmap_and_compl_into (TO, FROM)
  62
  63 /* Inclusive or a register set with a second register set.  */
  64 #define IOR_REG_SET(TO, FROM) bitmap_ior_into (TO, FROM)
  65
  66 /* Exclusive or a register set with a second register set.  */
  67 #define XOR_REG_SET(TO, FROM) bitmap_xor_into (TO, FROM)
  68
  69 /* Or into TO the register set FROM1 `and'ed with the complement of FROM2.  */
  70 #define IOR_AND_COMPL_REG_SET(TO, FROM1, FROM2) \
  71   bitmap_ior_and_compl_into (TO, FROM1, FROM2)
  72
  73 /* Clear a single register in a register set.  */
  74 #define CLEAR_REGNO_REG_SET(HEAD, REG) bitmap_clear_bit (HEAD, REG)
  75
  76 /* Set a single register in a register set.  */
  77 #define SET_REGNO_REG_SET(HEAD, REG) bitmap_set_bit (HEAD, REG)
  78
  79 /* Return true if a register is set in a register set.  */
  80 #define REGNO_REG_SET_P(TO, REG) bitmap_bit_p (TO, REG)
  81
  82 /* Copy the hard registers in a register set to the hard register set.  */
  83 extern void reg_set_to_hard_reg_set (HARD_REG_SET *, const_bitmap);
  84 #define REG_SET_TO_HARD_REG_SET(TO, FROM)                               \
  85 do {                                                                    \
  86   CLEAR_HARD_REG_SET (TO);                                              \
  87   reg_set_to_hard_reg_set (&TO, FROM);                                  \
  88 } while (0)
  89
  90 typedef bitmap_iterator reg_set_iterator;
  91
  92 /* Loop over all registers in REGSET, starting with MIN, setting REGNUM to the
  93    register number and executing CODE for all registers that are set.  */
  94 #define EXECUTE_IF_SET_IN_REG_SET(REGSET, MIN, REGNUM, RSI)     \
  95   EXECUTE_IF_SET_IN_BITMAP (REGSET, MIN, REGNUM, RSI)
  96
  97 /* Loop over all registers in REGSET1 and REGSET2, starting with MIN, setting
  98    REGNUM to the register number and executing CODE for all registers that are
  99    set in the first regset and not set in the second.  */
 100 #define EXECUTE_IF_AND_COMPL_IN_REG_SET(REGSET1, REGSET2, MIN, REGNUM, RSI) \
 101   EXECUTE_IF_AND_COMPL_IN_BITMAP (REGSET1, REGSET2, MIN, REGNUM, RSI)
 102
 103 /* Loop over all registers in REGSET1 and REGSET2, starting with MIN, setting
 104    REGNUM to the register number and executing CODE for all registers that are
 105    set in both regsets.  */
 106 #define EXECUTE_IF_AND_IN_REG_SET(REGSET1, REGSET2, MIN, REGNUM, RSI) \
 107   EXECUTE_IF_AND_IN_BITMAP (REGSET1, REGSET2, MIN, REGNUM, RSI) \
 108
 109 /* Same information as REGS_INVALIDATED_BY_CALL but in regset form to be used
 110    in dataflow more conveniently.  */
 111
 112 extern regset regs_invalidated_by_call_regset;
 113
 114 /* Type we use to hold basic block counters.  Should be at least
 115    64bit.  Although a counter cannot be negative, we use a signed
 116    type, because erroneous negative counts can be generated when the
 117    flow graph is manipulated by various optimizations.  A signed type
 118    makes those easy to detect.  */
 119 typedef HOST_WIDEST_INT gcov_type;
 120
 121 /* Control flow edge information.  */
 122 struct edge_def GTY(())
 123 {
 124   /* The two blocks at the ends of the edge.  */
 125   struct basic_block_def *src;
 126   struct basic_block_def *dest;
 127
 128   /* Instructions queued on the edge.  */
 129   union edge_def_insns {
 130     gimple_seq GTY ((tag ("true"))) g;
 131     rtx GTY ((tag ("false"))) r;
 132   } GTY ((desc ("current_ir_type () == IR_GIMPLE"))) insns;
 133
 134   /* Auxiliary info specific to a pass.  */
 135   PTR GTY ((skip (""))) aux;
 136
 137   /* Location of any goto implicit in the edge and associated BLOCK.  */
 138   tree goto_block;
 139   location_t goto_locus;
 140
 141   /* The index number corresponding to this edge in the edge vector
 142      dest->preds.  */
 143   unsigned int dest_idx;
 144
 145   int flags;                    /* see EDGE_* below  */
 146   int probability;              /* biased by REG_BR_PROB_BASE */
 147   gcov_type count;              /* Expected number of executions calculated
 148                                    in profile.c  */
 149 };
 150
 151 typedef struct edge_def *edge;
 152 typedef const struct edge_def *const_edge;
 153 DEF_VEC_P(edge);
 154 DEF_VEC_ALLOC_P(edge,gc);
 155 DEF_VEC_ALLOC_P(edge,heap);
 156
 157 #define EDGE_FALLTHRU           1       /* 'Straight line' flow */
 158 #define EDGE_ABNORMAL           2       /* Strange flow, like computed
 159                                            label, or eh */
 160 #define EDGE_ABNORMAL_CALL      4       /* Call with abnormal exit
 161                                            like an exception, or sibcall */
 162 #define EDGE_EH                 8       /* Exception throw */
 163 #define EDGE_FAKE               16      /* Not a real edge (profile.c) */
 164 #define EDGE_DFS_BACK           32      /* A backwards edge */
 165 #define EDGE_CAN_FALLTHRU       64      /* Candidate for straight line
 166                                            flow.  */
 167 #define EDGE_IRREDUCIBLE_LOOP   128     /* Part of irreducible loop.  */
 168 #define EDGE_SIBCALL            256     /* Edge from sibcall to exit.  */
 169 #define EDGE_LOOP_EXIT          512     /* Exit of a loop.  */
 170 #define EDGE_TRUE_VALUE         1024    /* Edge taken when controlling
 171                                            predicate is nonzero.  */
 172 #define EDGE_FALSE_VALUE        2048    /* Edge taken when controlling
 173                                            predicate is zero.  */
 174 #define EDGE_EXECUTABLE         4096    /* Edge is executable.  Only
 175                                            valid during SSA-CCP.  */
 176 #define EDGE_CROSSING           8192    /* Edge crosses between hot
 177                                            and cold sections, when we
 178                                            do partitioning.  */
 179 #define EDGE_ALL_FLAGS         16383
 180
 181 #define EDGE_COMPLEX    (EDGE_ABNORMAL | EDGE_ABNORMAL_CALL | EDGE_EH)
 182
 183 /* Counter summary from the last set of coverage counts read by
 184    profile.c.  */
 185 extern const struct gcov_ctr_summary *profile_info;
 186
 187 /* Declared in cfgloop.h.  */
 188 struct loop;
 189
 190 /* Declared in tree-flow.h.  */
 191 struct edge_prediction;
 192 struct rtl_bb_info;
 193
 194 /* A basic block is a sequence of instructions with only entry and
 195    only one exit.  If any one of the instructions are executed, they
 196    will all be executed, and in sequence from first to last.
 197
 198    There may be COND_EXEC instructions in the basic block.  The
 199    COND_EXEC *instructions* will be executed -- but if the condition
 200    is false the conditionally executed *expressions* will of course
 201    not be executed.  We don't consider the conditionally executed
 202    expression (which might have side-effects) to be in a separate
 203    basic block because the program counter will always be at the same
 204    location after the COND_EXEC instruction, regardless of whether the
 205    condition is true or not.
 206
 207    Basic blocks need not start with a label nor end with a jump insn.
 208    For example, a previous basic block may just "conditionally fall"
 209    into the succeeding basic block, and the last basic block need not
 210    end with a jump insn.  Block 0 is a descendant of the entry block.
 211
 212    A basic block beginning with two labels cannot have notes between
 213    the labels.
 214
 215    Data for jump tables are stored in jump_insns that occur in no
 216    basic block even though these insns can follow or precede insns in
 217    basic blocks.  */
 218
 219 /* Basic block information indexed by block number.  */
 220 struct basic_block_def GTY((chain_next ("%h.next_bb"), chain_prev ("%h.prev_bb")))
 221 {
 222   /* The edges into and out of the block.  */
 223   VEC(edge,gc) *preds;
 224   VEC(edge,gc) *succs;
 225
 226   /* Auxiliary info specific to a pass.  */
 227   PTR GTY ((skip (""))) aux;
 228
 229   /* Innermost loop containing the block.  */
 230   struct loop *loop_father;
 231
 232   /* The dominance and postdominance information node.  */
 233   struct et_node * GTY ((skip (""))) dom[2];
 234
 235   /* Previous and next blocks in the chain.  */
 236   struct basic_block_def *prev_bb;
 237   struct basic_block_def *next_bb;
 238
 239   union basic_block_il_dependent {
 240       struct gimple_bb_info * GTY ((tag ("0"))) gimple;
 241       struct rtl_bb_info * GTY ((tag ("1"))) rtl;
 242     } GTY ((desc ("((%1.flags & BB_RTL) != 0)"))) il;
 243
 244   /* Expected number of executions: calculated in profile.c.  */
 245   gcov_type count;
 246
 247   /* The index of this block.  */
 248   int index;
 249
 250   /* The loop depth of this block.  */
 251   int loop_depth;
 252
 253   /* Expected frequency.  Normalized to be in range 0 to BB_FREQ_MAX.  */
 254   int frequency;
 255
 256   /* Various flags.  See BB_* below.  */
 257   int flags;
 258 };
 259
 260 struct rtl_bb_info GTY(())
 261 {
 262   /* The first and last insns of the block.  */
 263   rtx head_;
 264   rtx end_;
 265
 266   /* In CFGlayout mode points to insn notes/jumptables to be placed just before
 267      and after the block.   */
 268   rtx header;
 269   rtx footer;
 270
 271   /* This field is used by the bb-reorder and tracer passes.  */
 272   int visited;
 273 };
 274
 275 struct gimple_bb_info GTY(())
 276 {
 277   /* Sequence of statements in this block.  */
 278   gimple_seq seq;
 279
 280   /* PHI nodes for this block.  */
 281   gimple_seq phi_nodes;
 282 };
 283
 284 typedef struct basic_block_def *basic_block;
 285 typedef const struct basic_block_def *const_basic_block;
 286
 287 DEF_VEC_P(basic_block);
 288 DEF_VEC_ALLOC_P(basic_block,gc);
 289 DEF_VEC_ALLOC_P(basic_block,heap);
 290
 291 #define BB_FREQ_MAX 10000
 292
 293 /* Masks for basic_block.flags.
 294
 295    BB_HOT_PARTITION and BB_COLD_PARTITION should be preserved throughout
 296    the compilation, so they are never cleared.
 297
 298    All other flags may be cleared by clear_bb_flags().  It is generally
 299    a bad idea to rely on any flags being up-to-date.  */
 300
 301 enum bb_flags
 302 {
 303   /* Only set on blocks that have just been created by create_bb.  */
 304   BB_NEW = 1 << 0,
 305
 306   /* Set by find_unreachable_blocks.  Do not rely on this being set in any
 307      pass.  */
 308   BB_REACHABLE = 1 << 1,
 309
 310   /* Set for blocks in an irreducible loop by loop analysis.  */
 311   BB_IRREDUCIBLE_LOOP = 1 << 2,
 312
 313   /* Set on blocks that may actually not be single-entry single-exit block.  */
 314   BB_SUPERBLOCK = 1 << 3,
 315
 316   /* Set on basic blocks that the scheduler should not touch.  This is used
 317      by SMS to prevent other schedulers from messing with the loop schedule.  */
 318   BB_DISABLE_SCHEDULE = 1 << 4,
 319
 320   /* Set on blocks that should be put in a hot section.  */
 321   BB_HOT_PARTITION = 1 << 5,
 322
 323   /* Set on blocks that should be put in a cold section.  */
 324   BB_COLD_PARTITION = 1 << 6,
 325
 326   /* Set on block that was duplicated.  */
 327   BB_DUPLICATED = 1 << 7,
 328
 329   /* Set if the label at the top of this block is the target of a non-local goto.  */
 330   BB_NON_LOCAL_GOTO_TARGET = 1 << 8,
 331
 332   /* Set on blocks that are in RTL format.  */
 333   BB_RTL = 1 << 9 ,
 334
 335   /* Set on blocks that are forwarder blocks.
 336      Only used in cfgcleanup.c.  */
 337   BB_FORWARDER_BLOCK = 1 << 10,
 338
 339   /* Set on blocks that cannot be threaded through.
 340      Only used in cfgcleanup.c.  */
 341   BB_NONTHREADABLE_BLOCK = 1 << 11
 342 };
 343
 344 /* Dummy flag for convenience in the hot/cold partitioning code.  */
 345 #define BB_UNPARTITIONED        0
 346
 347 /* Partitions, to be used when partitioning hot and cold basic blocks into
 348    separate sections.  */
 349 #define BB_PARTITION(bb) ((bb)->flags & (BB_HOT_PARTITION|BB_COLD_PARTITION))
 350 #define BB_SET_PARTITION(bb, part) do {                                 \
 351   basic_block bb_ = (bb);                                               \
 352   bb_->flags = ((bb_->flags & ~(BB_HOT_PARTITION|BB_COLD_PARTITION))    \
 353                 | (part));                                              \
 354 } while (0)
 355
 356 #define BB_COPY_PARTITION(dstbb, srcbb) \
 357   BB_SET_PARTITION (dstbb, BB_PARTITION (srcbb))
 358
 359 /* State of dominance information.  */
 360
 361 enum dom_state
 362 {
 363   DOM_NONE,             /* Not computed at all.  */
 364   DOM_NO_FAST_QUERY,    /* The data is OK, but the fast query data are not usable.  */
 365   DOM_OK                /* Everything is ok.  */
 366 };
 367
 368 /* A structure to group all the per-function control flow graph data.
 369    The x_* prefixing is necessary because otherwise references to the
 370    fields of this struct are interpreted as the defines for backward
 371    source compatibility following the definition of this struct.  */
 372 struct control_flow_graph GTY(())
 373 {
 374   /* Block pointers for the exit and entry of a function.
 375      These are always the head and tail of the basic block list.  */
 376   basic_block x_entry_block_ptr;
 377   basic_block x_exit_block_ptr;
 378
 379   /* Index by basic block number, get basic block struct info.  */
 380   VEC(basic_block,gc) *x_basic_block_info;
 381
 382   /* Number of basic blocks in this flow graph.  */
 383   int x_n_basic_blocks;
 384
 385   /* Number of edges in this flow graph.  */
 386   int x_n_edges;
 387
 388   /* The first free basic block number.  */
 389   int x_last_basic_block;
 390
 391   /* Mapping of labels to their associated blocks.  At present
 392      only used for the gimple CFG.  */
 393   VEC(basic_block,gc) *x_label_to_block_map;
 394
 395   enum profile_status {
 396     PROFILE_ABSENT,
 397     PROFILE_GUESSED,
 398     PROFILE_READ
 399   } x_profile_status;
 400
 401   /* Whether the dominators and the postdominators are available.  */
 402   enum dom_state x_dom_computed[2];
 403
 404   /* Number of basic blocks in the dominance tree.  */
 405   unsigned x_n_bbs_in_dom_tree[2];
 406
 407   /* Maximal number of entities in the single jumptable.  Used to estimate
 408      final flowgraph size.  */
 409   int max_jumptable_ents;
 410
 411   /* UIDs for LABEL_DECLs.  */
 412   int last_label_uid;
 413 };
 414
 415 /* Defines for accessing the fields of the CFG structure for function FN.  */
 416 #define ENTRY_BLOCK_PTR_FOR_FUNCTION(FN)     ((FN)->cfg->x_entry_block_ptr)
 417 #define EXIT_BLOCK_PTR_FOR_FUNCTION(FN)      ((FN)->cfg->x_exit_block_ptr)
 418 #define basic_block_info_for_function(FN)    ((FN)->cfg->x_basic_block_info)
 419 #define n_basic_blocks_for_function(FN)      ((FN)->cfg->x_n_basic_blocks)
 420 #define n_edges_for_function(FN)             ((FN)->cfg->x_n_edges)
 421 #define last_basic_block_for_function(FN)    ((FN)->cfg->x_last_basic_block)
 422 #define label_to_block_map_for_function(FN)  ((FN)->cfg->x_label_to_block_map)
 423 #define profile_status_for_function(FN)      ((FN)->cfg->x_profile_status)
 424
 425 #define BASIC_BLOCK_FOR_FUNCTION(FN,N) \
 426   (VEC_index (basic_block, basic_block_info_for_function(FN), (N)))
 427 #define SET_BASIC_BLOCK_FOR_FUNCTION(FN,N,BB) \
 428   (VEC_replace (basic_block, basic_block_info_for_function(FN), (N), (BB)))
 429
 430 /* Defines for textual backward source compatibility.  */
 431 #define ENTRY_BLOCK_PTR         (cfun->cfg->x_entry_block_ptr)
 432 #define EXIT_BLOCK_PTR          (cfun->cfg->x_exit_block_ptr)
 433 #define basic_block_info        (cfun->cfg->x_basic_block_info)
 434 #define n_basic_blocks          (cfun->cfg->x_n_basic_blocks)
 435 #define n_edges                 (cfun->cfg->x_n_edges)
 436 #define last_basic_block        (cfun->cfg->x_last_basic_block)
 437 #define label_to_block_map      (cfun->cfg->x_label_to_block_map)
 438 #define profile_status          (cfun->cfg->x_profile_status)
 439
 440 #define BASIC_BLOCK(N)          (VEC_index (basic_block, basic_block_info, (N)))
 441 #define SET_BASIC_BLOCK(N,BB)   (VEC_replace (basic_block, basic_block_info, (N), (BB)))
 442
 443 /* For iterating over basic blocks.  */
 444 #define FOR_BB_BETWEEN(BB, FROM, TO, DIR) \
 445   for (BB = FROM; BB != TO; BB = BB->DIR)
 446
 447 #define FOR_EACH_BB_FN(BB, FN) \
 448   FOR_BB_BETWEEN (BB, (FN)->cfg->x_entry_block_ptr->next_bb, (FN)->cfg->x_exit_block_ptr, next_bb)
 449
 450 #define FOR_EACH_BB(BB) FOR_EACH_BB_FN (BB, cfun)
 451
 452 #define FOR_EACH_BB_REVERSE_FN(BB, FN) \
 453   FOR_BB_BETWEEN (BB, (FN)->cfg->x_exit_block_ptr->prev_bb, (FN)->cfg->x_entry_block_ptr, prev_bb)
 454
 455 #define FOR_EACH_BB_REVERSE(BB) FOR_EACH_BB_REVERSE_FN(BB, cfun)
 456
 457 /* For iterating over insns in basic block.  */
 458 #define FOR_BB_INSNS(BB, INSN)                  \
 459   for ((INSN) = BB_HEAD (BB);                   \
 460        (INSN) && (INSN) != NEXT_INSN (BB_END (BB));     \
 461        (INSN) = NEXT_INSN (INSN))
 462
 463 /* For iterating over insns in basic block when we might remove the
 464    current insn.  */
 465 #define FOR_BB_INSNS_SAFE(BB, INSN, CURR)                       \
 466   for ((INSN) = BB_HEAD (BB), (CURR) = (INSN) ? NEXT_INSN ((INSN)): NULL;       \
 467        (INSN) && (INSN) != NEXT_INSN (BB_END (BB));     \
 468        (INSN) = (CURR), (CURR) = (INSN) ? NEXT_INSN ((INSN)) : NULL)
 469
 470 #define FOR_BB_INSNS_REVERSE(BB, INSN)          \
 471   for ((INSN) = BB_END (BB);                    \
 472        (INSN) && (INSN) != PREV_INSN (BB_HEAD (BB));    \
 473        (INSN) = PREV_INSN (INSN))
 474
 475 #define FOR_BB_INSNS_REVERSE_SAFE(BB, INSN, CURR)       \
 476   for ((INSN) = BB_END (BB),(CURR) = (INSN) ? PREV_INSN ((INSN)) : NULL;        \
 477        (INSN) && (INSN) != PREV_INSN (BB_HEAD (BB));    \
 478        (INSN) = (CURR), (CURR) = (INSN) ? PREV_INSN ((INSN)) : NULL)
 479
 480 /* Cycles through _all_ basic blocks, even the fake ones (entry and
 481    exit block).  */
 482
 483 #define FOR_ALL_BB(BB) \
 484   for (BB = ENTRY_BLOCK_PTR; BB; BB = BB->next_bb)
 485
 486 #define FOR_ALL_BB_FN(BB, FN) \
 487   for (BB = ENTRY_BLOCK_PTR_FOR_FUNCTION (FN); BB; BB = BB->next_bb)
 488
 489 extern bitmap_obstack reg_obstack;
 490
 491 \f
 492 /* Stuff for recording basic block info.  */
 493
 494 #define BB_HEAD(B)      (B)->il.rtl->head_
 495 #define BB_END(B)       (B)->il.rtl->end_
 496
 497 /* Special block numbers [markers] for entry and exit.  */
 498 #define ENTRY_BLOCK (0)
 499 #define EXIT_BLOCK (1)
 500
 501 /* The two blocks that are always in the cfg.  */
 502 #define NUM_FIXED_BLOCKS (2)
 503
 504
 505 #define BLOCK_NUM(INSN)       (BLOCK_FOR_INSN (INSN)->index + 0)
 506 #define set_block_for_insn(INSN, BB)  (BLOCK_FOR_INSN (INSN) = BB)
 507
 508 extern void compute_bb_for_insn (void);
 509 extern unsigned int free_bb_for_insn (void);
 510 extern void update_bb_for_insn (basic_block);
 511
 512 extern void insert_insn_on_edge (rtx, edge);
 513 basic_block split_edge_and_insert (edge, rtx);
 514
 515 extern void commit_edge_insertions (void);
 516
 517 extern void remove_fake_edges (void);
 518 extern void remove_fake_exit_edges (void);
 519 extern void add_noreturn_fake_exit_edges (void);
 520 extern void connect_infinite_loops_to_exit (void);
 521 extern edge unchecked_make_edge (basic_block, basic_block, int);
 522 extern edge cached_make_edge (sbitmap, basic_block, basic_block, int);
 523 extern edge make_edge (basic_block, basic_block, int);
 524 extern edge make_single_succ_edge (basic_block, basic_block, int);
 525 extern void remove_edge_raw (edge);
 526 extern void redirect_edge_succ (edge, basic_block);
 527 extern edge redirect_edge_succ_nodup (edge, basic_block);
 528 extern void redirect_edge_pred (edge, basic_block);
 529 extern basic_block create_basic_block_structure (rtx, rtx, rtx, basic_block);
 530 extern void clear_bb_flags (void);
 531 extern int post_order_compute (int *, bool, bool);
 532 extern int inverted_post_order_compute (int *);
 533 extern int pre_and_rev_post_order_compute (int *, int *, bool);
 534 extern int dfs_enumerate_from (basic_block, int,
 535                                bool (*)(const_basic_block, const void *),
 536                                basic_block *, int, const void *);
 537 extern void compute_dominance_frontiers (bitmap *);
 538 extern bitmap compute_idf (bitmap, bitmap *);
 539 extern void dump_bb_info (basic_block, bool, bool, int, const char *, FILE *);
 540 extern void dump_edge_info (FILE *, edge, int);
 541 extern void brief_dump_cfg (FILE *);
 542 extern void clear_edges (void);
 543 extern void scale_bbs_frequencies_int (basic_block *, int, int, int);
 544 extern void scale_bbs_frequencies_gcov_type (basic_block *, int, gcov_type,
 545                                              gcov_type);
 546
 547 /* Structure to group all of the information to process IF-THEN and
 548    IF-THEN-ELSE blocks for the conditional execution support.  This
 549    needs to be in a public file in case the IFCVT macros call
 550    functions passing the ce_if_block data structure.  */
 551
 552 typedef struct ce_if_block
 553 {
 554   basic_block test_bb;                  /* First test block.  */
 555   basic_block then_bb;                  /* THEN block.  */
 556   basic_block else_bb;                  /* ELSE block or NULL.  */
 557   basic_block join_bb;                  /* Join THEN/ELSE blocks.  */
 558   basic_block last_test_bb;             /* Last bb to hold && or || tests.  */
 559   int num_multiple_test_blocks;         /* # of && and || basic blocks.  */
 560   int num_and_and_blocks;               /* # of && blocks.  */
 561   int num_or_or_blocks;                 /* # of || blocks.  */
 562   int num_multiple_test_insns;          /* # of insns in && and || blocks.  */
 563   int and_and_p;                        /* Complex test is &&.  */
 564   int num_then_insns;                   /* # of insns in THEN block.  */
 565   int num_else_insns;                   /* # of insns in ELSE block.  */
 566   int pass;                             /* Pass number.  */
 567
 568 #ifdef IFCVT_EXTRA_FIELDS
 569   IFCVT_EXTRA_FIELDS                    /* Any machine dependent fields.  */
 570 #endif
 571
 572 } ce_if_block_t;
 573
 574 /* This structure maintains an edge list vector.  */
 575 struct edge_list
 576 {
 577   int num_blocks;
 578   int num_edges;
 579   edge *index_to_edge;
 580 };
 581
 582 /* The base value for branch probability notes and edge probabilities.  */
 583 #define REG_BR_PROB_BASE  10000
 584
 585 /* This is the value which indicates no edge is present.  */
 586 #define EDGE_INDEX_NO_EDGE      -1
 587
 588 /* EDGE_INDEX returns an integer index for an edge, or EDGE_INDEX_NO_EDGE
 589    if there is no edge between the 2 basic blocks.  */
 590 #define EDGE_INDEX(el, pred, succ) (find_edge_index ((el), (pred), (succ)))
 591
 592 /* INDEX_EDGE_PRED_BB and INDEX_EDGE_SUCC_BB return a pointer to the basic
 593    block which is either the pred or succ end of the indexed edge.  */
 594 #define INDEX_EDGE_PRED_BB(el, index)   ((el)->index_to_edge[(index)]->src)
 595 #define INDEX_EDGE_SUCC_BB(el, index)   ((el)->index_to_edge[(index)]->dest)
 596
 597 /* INDEX_EDGE returns a pointer to the edge.  */
 598 #define INDEX_EDGE(el, index)           ((el)->index_to_edge[(index)])
 599
 600 /* Number of edges in the compressed edge list.  */
 601 #define NUM_EDGES(el)                   ((el)->num_edges)
 602
 603 /* BB is assumed to contain conditional jump.  Return the fallthru edge.  */
 604 #define FALLTHRU_EDGE(bb)               (EDGE_SUCC ((bb), 0)->flags & EDGE_FALLTHRU \
 605                                          ? EDGE_SUCC ((bb), 0) : EDGE_SUCC ((bb), 1))
 606
 607 /* BB is assumed to contain conditional jump.  Return the branch edge.  */
 608 #define BRANCH_EDGE(bb)                 (EDGE_SUCC ((bb), 0)->flags & EDGE_FALLTHRU \
 609                                          ? EDGE_SUCC ((bb), 1) : EDGE_SUCC ((bb), 0))
 610
 611 /* Return expected execution frequency of the edge E.  */
 612 #define EDGE_FREQUENCY(e)               (((e)->src->frequency \
 613                                           * (e)->probability \
 614                                           + REG_BR_PROB_BASE / 2) \
 615                                          / REG_BR_PROB_BASE)
 616
 617 /* Return nonzero if edge is critical.  */
 618 #define EDGE_CRITICAL_P(e)              (EDGE_COUNT ((e)->src->succs) >= 2 \
 619                                          && EDGE_COUNT ((e)->dest->preds) >= 2)
 620
 621 #define EDGE_COUNT(ev)                  VEC_length (edge, (ev))
 622 #define EDGE_I(ev,i)                    VEC_index  (edge, (ev), (i))
 623 #define EDGE_PRED(bb,i)                 VEC_index  (edge, (bb)->preds, (i))
 624 #define EDGE_SUCC(bb,i)                 VEC_index  (edge, (bb)->succs, (i))
 625
 626 /* Returns true if BB has precisely one successor.  */
 627
 628 static inline bool
 629 single_succ_p (const_basic_block bb)
 630 {
 631   return EDGE_COUNT (bb->succs) == 1;
 632 }
 633
 634 /* Returns true if BB has precisely one predecessor.  */
 635
 636 static inline bool
 637 single_pred_p (const_basic_block bb)
 638 {
 639   return EDGE_COUNT (bb->preds) == 1;
 640 }
 641
 642 /* Returns the single successor edge of basic block BB.  Aborts if
 643    BB does not have exactly one successor.  */
 644
 645 static inline edge
 646 single_succ_edge (const_basic_block bb)
 647 {
 648   gcc_assert (single_succ_p (bb));
 649   return EDGE_SUCC (bb, 0);
 650 }
 651
 652 /* Returns the single predecessor edge of basic block BB.  Aborts
 653    if BB does not have exactly one predecessor.  */
 654
 655 static inline edge
 656 single_pred_edge (const_basic_block bb)
 657 {
 658   gcc_assert (single_pred_p (bb));
 659   return EDGE_PRED (bb, 0);
 660 }
 661
 662 /* Returns the single successor block of basic block BB.  Aborts
 663    if BB does not have exactly one successor.  */
 664
 665 static inline basic_block
 666 single_succ (const_basic_block bb)
 667 {
 668   return single_succ_edge (bb)->dest;
 669 }
 670
 671 /* Returns the single predecessor block of basic block BB.  Aborts
 672    if BB does not have exactly one predecessor.*/
 673
 674 static inline basic_block
 675 single_pred (const_basic_block bb)
 676 {
 677   return single_pred_edge (bb)->src;
 678 }
 679
 680 /* Iterator object for edges.  */
 681
 682 typedef struct {
 683   unsigned index;
 684   VEC(edge,gc) **container;
 685 } edge_iterator;
 686
 687 static inline VEC(edge,gc) *
 688 ei_container (edge_iterator i)
 689 {
 690   gcc_assert (i.container);
 691   return *i.container;
 692 }
 693
 694 #define ei_start(iter) ei_start_1 (&(iter))
 695 #define ei_last(iter) ei_last_1 (&(iter))
 696
 697 /* Return an iterator pointing to the start of an edge vector.  */
 698 static inline edge_iterator
 699 ei_start_1 (VEC(edge,gc) **ev)
 700 {
 701   edge_iterator i;
 702
 703   i.index = 0;
 704   i.container = ev;
 705
 706   return i;
 707 }
 708
 709 /* Return an iterator pointing to the last element of an edge
 710    vector.  */
 711 static inline edge_iterator
 712 ei_last_1 (VEC(edge,gc) **ev)
 713 {
 714   edge_iterator i;
 715
 716   i.index = EDGE_COUNT (*ev) - 1;
 717   i.container = ev;
 718
 719   return i;
 720 }
 721
 722 /* Is the iterator `i' at the end of the sequence?  */
 723 static inline bool
 724 ei_end_p (edge_iterator i)
 725 {
 726   return (i.index == EDGE_COUNT (ei_container (i)));
 727 }
 728
 729 /* Is the iterator `i' at one position before the end of the
 730    sequence?  */
 731 static inline bool
 732 ei_one_before_end_p (edge_iterator i)
 733 {
 734   return (i.index + 1 == EDGE_COUNT (ei_container (i)));
 735 }
 736
 737 /* Advance the iterator to the next element.  */
 738 static inline void
 739 ei_next (edge_iterator *i)
 740 {
 741   gcc_assert (i->index < EDGE_COUNT (ei_container (*i)));
 742   i->index++;
 743 }
 744
 745 /* Move the iterator to the previous element.  */
 746 static inline void
 747 ei_prev (edge_iterator *i)
 748 {
 749   gcc_assert (i->index > 0);
 750   i->index--;
 751 }
 752
 753 /* Return the edge pointed to by the iterator `i'.  */
 754 static inline edge
 755 ei_edge (edge_iterator i)
 756 {
 757   return EDGE_I (ei_container (i), i.index);
 758 }
 759
 760 /* Return an edge pointed to by the iterator.  Do it safely so that
 761    NULL is returned when the iterator is pointing at the end of the
 762    sequence.  */
 763 static inline edge
 764 ei_safe_edge (edge_iterator i)
 765 {
 766   return !ei_end_p (i) ? ei_edge (i) : NULL;
 767 }
 768
 769 /* Return 1 if we should continue to iterate.  Return 0 otherwise.
 770    *Edge P is set to the next edge if we are to continue to iterate
 771    and NULL otherwise.  */
 772
 773 static inline bool
 774 ei_cond (edge_iterator ei, edge *p)
 775 {
 776   if (!ei_end_p (ei))
 777     {
 778       *p = ei_edge (ei);
 779       return 1;
 780     }
 781   else
 782     {
 783       *p = NULL;
 784       return 0;
 785     }
 786 }
 787
 788 /* This macro serves as a convenient way to iterate each edge in a
 789    vector of predecessor or successor edges.  It must not be used when
 790    an element might be removed during the traversal, otherwise
 791    elements will be missed.  Instead, use a for-loop like that shown
 792    in the following pseudo-code:
 793
 794    FOR (ei = ei_start (bb->succs); (e = ei_safe_edge (ei)); )
 795      {
 796         IF (e != taken_edge)
 797           remove_edge (e);
 798         ELSE
 799           ei_next (&ei);
 800      }
 801 */
 802
 803 #define FOR_EACH_EDGE(EDGE,ITER,EDGE_VEC)       \
 804   for ((ITER) = ei_start ((EDGE_VEC));          \
 805        ei_cond ((ITER), &(EDGE));               \
 806        ei_next (&(ITER)))
 807
 808 struct edge_list * create_edge_list (void);
 809 void free_edge_list (struct edge_list *);
 810 void print_edge_list (FILE *, struct edge_list *);
 811 void verify_edge_list (FILE *, struct edge_list *);
 812 int find_edge_index (struct edge_list *, basic_block, basic_block);
 813 edge find_edge (basic_block, basic_block);
 814
 815 #define CLEANUP_EXPENSIVE       1       /* Do relatively expensive optimizations
 816                                            except for edge forwarding */
 817 #define CLEANUP_CROSSJUMP       2       /* Do crossjumping.  */
 818 #define CLEANUP_POST_REGSTACK   4       /* We run after reg-stack and need
 819                                            to care REG_DEAD notes.  */
 820 #define CLEANUP_THREADING       8       /* Do jump threading.  */
 821 #define CLEANUP_NO_INSN_DEL     16      /* Do not try to delete trivially dead
 822                                            insns.  */
 823 #define CLEANUP_CFGLAYOUT       32      /* Do cleanup in cfglayout mode.  */
 824
 825 /* In lcm.c */
 826 extern struct edge_list *pre_edge_lcm (int, sbitmap *, sbitmap *,
 827                                        sbitmap *, sbitmap *, sbitmap **,
 828                                        sbitmap **);
 829 extern struct edge_list *pre_edge_rev_lcm (int, sbitmap *,
 830                                            sbitmap *, sbitmap *,
 831                                            sbitmap *, sbitmap **,
 832                                            sbitmap **);
 833 extern void compute_available (sbitmap *, sbitmap *, sbitmap *, sbitmap *);
 834
 835 /* In predict.c */
 836 extern bool maybe_hot_bb_p (const_basic_block);
 837 extern bool maybe_hot_edge_p (edge);
 838 extern bool probably_never_executed_bb_p (const_basic_block);
 839 extern bool optimize_bb_for_size_p (const_basic_block);
 840 extern bool optimize_bb_for_speed_p (const_basic_block);
 841 extern bool optimize_edge_for_size_p (edge);
 842 extern bool optimize_edge_for_speed_p (edge);
 843 extern bool optimize_function_for_size_p (struct function *);
 844 extern bool optimize_function_for_speed_p (struct function *);
 845 extern bool optimize_loop_for_size_p (struct loop *);
 846 extern bool optimize_loop_for_speed_p (struct loop *);
 847 extern bool optimize_loop_nest_for_size_p (struct loop *);
 848 extern bool optimize_loop_nest_for_speed_p (struct loop *);
 849 extern bool gimple_predicted_by_p (const_basic_block, enum br_predictor);
 850 extern bool rtl_predicted_by_p (const_basic_block, enum br_predictor);
 851 extern void gimple_predict_edge (edge, enum br_predictor, int);
 852 extern void rtl_predict_edge (edge, enum br_predictor, int);
 853 extern void predict_edge_def (edge, enum br_predictor, enum prediction);
 854 extern void guess_outgoing_edge_probabilities (basic_block);
 855 extern void remove_predictions_associated_with_edge (edge);
 856 extern bool edge_probability_reliable_p (const_edge);
 857 extern bool br_prob_note_reliable_p (const_rtx);
 858 extern bool predictable_edge_p (edge);
 859
 860 /* In cfg.c  */
 861 extern void dump_regset (regset, FILE *);
 862 extern void debug_regset (regset);
 863 extern void init_flow (struct function *);
 864 extern void debug_bb (basic_block);
 865 extern basic_block debug_bb_n (int);
 866 extern void dump_regset (regset, FILE *);
 867 extern void debug_regset (regset);
 868 extern void expunge_block (basic_block);
 869 extern void link_block (basic_block, basic_block);
 870 extern void unlink_block (basic_block);
 871 extern void compact_blocks (void);
 872 extern basic_block alloc_block (void);
 873 extern void alloc_aux_for_block (basic_block, int);
 874 extern void alloc_aux_for_blocks (int);
 875 extern void clear_aux_for_blocks (void);
 876 extern void free_aux_for_blocks (void);
 877 extern void alloc_aux_for_edge (edge, int);
 878 extern void alloc_aux_for_edges (int);
 879 extern void clear_aux_for_edges (void);
 880 extern void free_aux_for_edges (void);
 881
 882 /* In cfganal.c  */
 883 extern void find_unreachable_blocks (void);
 884 extern bool forwarder_block_p (const_basic_block);
 885 extern bool can_fallthru (basic_block, basic_block);
 886 extern bool could_fall_through (basic_block, basic_block);
 887 extern void flow_nodes_print (const char *, const_sbitmap, FILE *);
 888 extern void flow_edge_list_print (const char *, const edge *, int, FILE *);
 889
 890 /* In cfgrtl.c  */
 891 extern basic_block force_nonfallthru (edge);
 892 extern rtx block_label (basic_block);
 893 extern bool purge_all_dead_edges (void);
 894 extern bool purge_dead_edges (basic_block);
 895
 896 /* In cfgbuild.c.  */
 897 extern void find_many_sub_basic_blocks (sbitmap);
 898 extern void rtl_make_eh_edge (sbitmap, basic_block, rtx);
 899
 900 /* In cfgcleanup.c.  */
 901 extern bool cleanup_cfg (int);
 902 extern bool delete_unreachable_blocks (void);
 903
 904 extern bool mark_dfs_back_edges (void);
 905 extern void set_edge_can_fallthru_flag (void);
 906 extern void update_br_prob_note (basic_block);
 907 extern void fixup_abnormal_edges (void);
 908 extern bool inside_basic_block_p (const_rtx);
 909 extern bool control_flow_insn_p (const_rtx);
 910 extern rtx get_last_bb_insn (basic_block);
 911
 912 /* In bb-reorder.c */
 913 extern void reorder_basic_blocks (void);
 914
 915 /* In dominance.c */
 916
 917 enum cdi_direction
 918 {
 919   CDI_DOMINATORS = 1,
 920   CDI_POST_DOMINATORS = 2
 921 };
 922
 923 extern enum dom_state dom_info_state (enum cdi_direction);
 924 extern void set_dom_info_availability (enum cdi_direction, enum dom_state);
 925 extern bool dom_info_available_p (enum cdi_direction);
 926 extern void calculate_dominance_info (enum cdi_direction);
 927 extern void free_dominance_info (enum cdi_direction);
 928 extern basic_block nearest_common_dominator (enum cdi_direction,
 929                                              basic_block, basic_block);
 930 extern basic_block nearest_common_dominator_for_set (enum cdi_direction,
 931                                                      bitmap);
 932 extern void set_immediate_dominator (enum cdi_direction, basic_block,
 933                                      basic_block);
 934 extern basic_block get_immediate_dominator (enum cdi_direction, basic_block);
 935 extern bool dominated_by_p (enum cdi_direction, const_basic_block, const_basic_block);
 936 extern VEC (basic_block, heap) *get_dominated_by (enum cdi_direction, basic_block);
 937 extern VEC (basic_block, heap) *get_dominated_by_region (enum cdi_direction,
 938                                                          basic_block *,
 939                                                          unsigned);
 940 extern VEC (basic_block, heap) *get_all_dominated_blocks (enum cdi_direction,
 941                                                           basic_block);
 942 extern void add_to_dominance_info (enum cdi_direction, basic_block);
 943 extern void delete_from_dominance_info (enum cdi_direction, basic_block);
 944 basic_block recompute_dominator (enum cdi_direction, basic_block);
 945 extern void redirect_immediate_dominators (enum cdi_direction, basic_block,
 946                                            basic_block);
 947 extern void iterate_fix_dominators (enum cdi_direction,
 948                                     VEC (basic_block, heap) *, bool);
 949 extern void verify_dominators (enum cdi_direction);
 950 extern basic_block first_dom_son (enum cdi_direction, basic_block);
 951 extern basic_block next_dom_son (enum cdi_direction, basic_block);
 952 unsigned bb_dom_dfs_in (enum cdi_direction, basic_block);
 953 unsigned bb_dom_dfs_out (enum cdi_direction, basic_block);
 954
 955 extern edge try_redirect_by_replacing_jump (edge, basic_block, bool);
 956 extern void break_superblocks (void);
 957 extern void relink_block_chain (bool);
 958 extern void check_bb_profile (basic_block, FILE *);
 959 extern void update_bb_profile_for_threading (basic_block, int, gcov_type, edge);
 960 extern void init_rtl_bb_info (basic_block);
 961
 962 extern void initialize_original_copy_tables (void);
 963 extern void free_original_copy_tables (void);
 964 extern void set_bb_original (basic_block, basic_block);
 965 extern basic_block get_bb_original (basic_block);
 966 extern void set_bb_copy (basic_block, basic_block);
 967 extern basic_block get_bb_copy (basic_block);
 968 void set_loop_copy (struct loop *, struct loop *);
 969 struct loop *get_loop_copy (struct loop *);
 970
 971
 972 extern rtx insert_insn_end_bb_new (rtx, basic_block);
 973
 974 #include "cfghooks.h"
 975
 976 /* Return true when one of the predecessor edges of BB is marked with EDGE_EH.  */
 977 static inline bool
 978 bb_has_eh_pred (basic_block bb)
 979 {
 980   edge e;
 981   edge_iterator ei;
 982
 983   FOR_EACH_EDGE (e, ei, bb->preds)
 984     {
 985       if (e->flags & EDGE_EH)
 986         return true;
 987     }
 988   return false;
 989 }
 990
 991 /* Return true when one of the predecessor edges of BB is marked with EDGE_ABNORMAL.  */
 992 static inline bool
 993 bb_has_abnormal_pred (basic_block bb)
 994 {
 995   edge e;
 996   edge_iterator ei;
 997
 998   FOR_EACH_EDGE (e, ei, bb->preds)
 999     {
1000       if (e->flags & EDGE_ABNORMAL)
1001         return true;
1002     }
1003   return false;
1004 }
1005
1006 /* In cfgloopmanip.c.  */
1007 extern edge mfb_kj_edge;
1008 extern bool mfb_keep_just (edge);
1009
1010 /* In cfgexpand.c.  */
1011 extern void rtl_profile_for_bb (basic_block);
1012 extern void rtl_profile_for_edge (edge);
1013 extern void default_rtl_profile (void);
1014
1015 #endif /* GCC_BASIC_BLOCK_H */