gcc/basic-block.h

   1 /* Define control and data flow tables, and regsets.
   2    Copyright (C) 1987, 1997, 1998, 1999, 2000, 2001, 2002
   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
  30 /* Head of register set linked list.  */
  31 typedef bitmap_head regset_head;
  32 /* A pointer to a regset_head.  */
  33 typedef bitmap regset;
  34
  35 /* Initialize a new regset.  */
  36 #define INIT_REG_SET(HEAD) bitmap_initialize (HEAD)
  37
  38 /* Clear a register set by freeing up the linked list.  */
  39 #define CLEAR_REG_SET(HEAD) bitmap_clear (HEAD)
  40
  41 /* Copy a register set to another register set.  */
  42 #define COPY_REG_SET(TO, FROM) bitmap_copy (TO, FROM)
  43
  44 /* Compare two register sets.  */
  45 #define REG_SET_EQUAL_P(A, B) bitmap_equal_p (A, B)
  46
  47 /* `and' a register set with a second register set.  */
  48 #define AND_REG_SET(TO, FROM) bitmap_operation (TO, TO, FROM, BITMAP_AND)
  49
  50 /* `and' the complement of a register set with a register set.  */
  51 #define AND_COMPL_REG_SET(TO, FROM) \
  52   bitmap_operation (TO, TO, FROM, BITMAP_AND_COMPL)
  53
  54 /* Inclusive or a register set with a second register set.  */
  55 #define IOR_REG_SET(TO, FROM) bitmap_operation (TO, TO, FROM, BITMAP_IOR)
  56
  57 /* Exclusive or a register set with a second register set.  */
  58 #define XOR_REG_SET(TO, FROM) bitmap_operation (TO, TO, FROM, BITMAP_XOR)
  59
  60 /* Or into TO the register set FROM1 `and'ed with the complement of FROM2.  */
  61 #define IOR_AND_COMPL_REG_SET(TO, FROM1, FROM2) \
  62   bitmap_ior_and_compl (TO, FROM1, FROM2)
  63
  64 /* Clear a single register in a register set.  */
  65 #define CLEAR_REGNO_REG_SET(HEAD, REG) bitmap_clear_bit (HEAD, REG)
  66
  67 /* Set a single register in a register set.  */
  68 #define SET_REGNO_REG_SET(HEAD, REG) bitmap_set_bit (HEAD, REG)
  69
  70 /* Return true if a register is set in a register set.  */
  71 #define REGNO_REG_SET_P(TO, REG) bitmap_bit_p (TO, REG)
  72
  73 /* Copy the hard registers in a register set to the hard register set.  */
  74 extern void reg_set_to_hard_reg_set PARAMS ((HARD_REG_SET *, bitmap));
  75 #define REG_SET_TO_HARD_REG_SET(TO, FROM)                               \
  76 do {                                                                    \
  77   CLEAR_HARD_REG_SET (TO);                                              \
  78   reg_set_to_hard_reg_set (&TO, FROM);                                  \
  79 } while (0)
  80
  81 /* Loop over all registers in REGSET, starting with MIN, setting REGNUM to the
  82    register number and executing CODE for all registers that are set.  */
  83 #define EXECUTE_IF_SET_IN_REG_SET(REGSET, MIN, REGNUM, CODE)            \
  84   EXECUTE_IF_SET_IN_BITMAP (REGSET, MIN, REGNUM, CODE)
  85
  86 /* Loop over all registers in REGSET1 and REGSET2, starting with MIN, setting
  87    REGNUM to the register number and executing CODE for all registers that are
  88    set in the first regset and not set in the second.  */
  89 #define EXECUTE_IF_AND_COMPL_IN_REG_SET(REGSET1, REGSET2, MIN, REGNUM, CODE) \
  90   EXECUTE_IF_AND_COMPL_IN_BITMAP (REGSET1, REGSET2, MIN, REGNUM, CODE)
  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 both regsets.  */
  95 #define EXECUTE_IF_AND_IN_REG_SET(REGSET1, REGSET2, MIN, REGNUM, CODE) \
  96   EXECUTE_IF_AND_IN_BITMAP (REGSET1, REGSET2, MIN, REGNUM, CODE)
  97
  98 /* Allocate a register set with oballoc.  */
  99 #define OBSTACK_ALLOC_REG_SET(OBSTACK) BITMAP_OBSTACK_ALLOC (OBSTACK)
 100
 101 /* Initialize a register set.  Returns the new register set.  */
 102 #define INITIALIZE_REG_SET(HEAD) bitmap_initialize (&HEAD)
 103
 104 /* Do any cleanup needed on a regset when it is no longer used.  */
 105 #define FREE_REG_SET(REGSET) BITMAP_FREE(REGSET)
 106
 107 /* Do any one-time initializations needed for regsets.  */
 108 #define INIT_ONCE_REG_SET() BITMAP_INIT_ONCE ()
 109
 110 /* Grow any tables needed when the number of registers is calculated
 111    or extended.  For the linked list allocation, nothing needs to
 112    be done, other than zero the statistics on the first allocation.  */
 113 #define MAX_REGNO_REG_SET(NUM_REGS, NEW_P, RENUMBER_P)
 114
 115 /* Type we use to hold basic block counters.  Should be at least 64bit.  */
 116 typedef HOST_WIDEST_INT gcov_type;
 117
 118 /* Control flow edge information.  */
 119 typedef struct edge_def {
 120   /* Links through the predecessor and successor lists.  */
 121   struct edge_def *pred_next, *succ_next;
 122
 123   /* The two blocks at the ends of the edge.  */
 124   struct basic_block_def *src, *dest;
 125
 126   /* Instructions queued on the edge.  */
 127   rtx insns;
 128
 129   /* Auxiliary info specific to a pass.  */
 130   void *aux;
 131
 132   int flags;                    /* see EDGE_* below  */
 133   int probability;              /* biased by REG_BR_PROB_BASE */
 134   gcov_type count;              /* Expected number of executions calculated
 135                                    in profile.c  */
 136 } *edge;
 137
 138 #define EDGE_FALLTHRU           1
 139 #define EDGE_ABNORMAL           2
 140 #define EDGE_ABNORMAL_CALL      4
 141 #define EDGE_EH                 8
 142 #define EDGE_FAKE               16
 143 #define EDGE_DFS_BACK           32
 144 #define EDGE_CAN_FALLTHRU       64
 145
 146 #define EDGE_COMPLEX    (EDGE_ABNORMAL | EDGE_ABNORMAL_CALL | EDGE_EH)
 147
 148
 149 /* A basic block is a sequence of instructions with only entry and
 150    only one exit.  If any one of the instructions are executed, they
 151    will all be executed, and in sequence from first to last.
 152
 153    There may be COND_EXEC instructions in the basic block.  The
 154    COND_EXEC *instructions* will be executed -- but if the condition
 155    is false the conditionally executed *expressions* will of course
 156    not be executed.  We don't consider the conditionally executed
 157    expression (which might have side-effects) to be in a separate
 158    basic block because the program counter will always be at the same
 159    location after the COND_EXEC instruction, regardless of whether the
 160    condition is true or not.
 161
 162    Basic blocks need not start with a label nor end with a jump insn.
 163    For example, a previous basic block may just "conditionally fall"
 164    into the succeeding basic block, and the last basic block need not
 165    end with a jump insn.  Block 0 is a descendant of the entry block.
 166
 167    A basic block beginning with two labels cannot have notes between
 168    the labels.
 169
 170    Data for jump tables are stored in jump_insns that occur in no
 171    basic block even though these insns can follow or precede insns in
 172    basic blocks.  */
 173
 174 /* Basic block information indexed by block number.  */
 175 typedef struct basic_block_def {
 176   /* The first and last insns of the block.  */
 177   rtx head, end;
 178
 179   /* The first and last trees of the block.  */
 180   tree head_tree;
 181   tree end_tree;
 182
 183   /* The edges into and out of the block.  */
 184   edge pred, succ;
 185
 186   /* Liveness info.  */
 187
 188   /* The registers that are modified within this in block.  */
 189   regset local_set;
 190   /* The registers that are conditionally modified within this block.
 191      In other words, registers that are set only as part of a
 192      COND_EXEC.  */
 193   regset cond_local_set;
 194   /* The registers that are live on entry to this block.
 195
 196      Note that in SSA form, global_live_at_start does not reflect the
 197      use of regs in phi functions, since the liveness of these regs
 198      may depend on which edge was taken into the block.  */
 199   regset global_live_at_start;
 200   /* The registers that are live on exit from this block.  */
 201   regset global_live_at_end;
 202
 203   /* Auxiliary info specific to a pass.  */
 204   void *aux;
 205
 206   /* The index of this block.  */
 207   int index;
 208
 209   /* Previous and next blocks in the chain.  */
 210   struct basic_block_def *prev_bb, *next_bb;
 211
 212   /* The loop depth of this block.  */
 213   int loop_depth;
 214
 215   /* Outermost loop containing the block.  */
 216   struct loop *loop_father;
 217
 218   /* Expected number of executions: calculated in profile.c.  */
 219   gcov_type count;
 220
 221   /* Expected frequency.  Normalized to be in range 0 to BB_FREQ_MAX.  */
 222   int frequency;
 223
 224   /* Various flags.  See BB_* below.  */
 225   int flags;
 226 } *basic_block;
 227
 228 #define BB_FREQ_MAX 10000
 229
 230 /* Masks for basic_block.flags.  */
 231 #define BB_DIRTY                1
 232 #define BB_NEW                  2
 233 #define BB_REACHABLE            4
 234 #define BB_VISITED              8
 235
 236 /* Number of basic blocks in the current function.  */
 237
 238 extern int n_basic_blocks;
 239
 240 /* First free basic block number.  */
 241
 242 extern int last_basic_block;
 243
 244 /* Number of edges in the current function.  */
 245
 246 extern int n_edges;
 247
 248 /* Index by basic block number, get basic block struct info.  */
 249
 250 extern varray_type basic_block_info;
 251
 252 #define BASIC_BLOCK(N)  (VARRAY_BB (basic_block_info, (N)))
 253
 254 /* For iterating over basic blocks.  */
 255 #define FOR_BB_BETWEEN(BB, FROM, TO, DIR) \
 256   for (BB = FROM; BB != TO; BB = BB->DIR)
 257
 258 #define FOR_EACH_BB(BB) \
 259   FOR_BB_BETWEEN (BB, ENTRY_BLOCK_PTR->next_bb, EXIT_BLOCK_PTR, next_bb)
 260
 261 #define FOR_EACH_BB_REVERSE(BB) \
 262   FOR_BB_BETWEEN (BB, EXIT_BLOCK_PTR->prev_bb, ENTRY_BLOCK_PTR, prev_bb)
 263
 264 /* What registers are live at the setjmp call.  */
 265
 266 extern regset regs_live_at_setjmp;
 267
 268 /* Special labels found during CFG build.  */
 269
 270 extern rtx label_value_list, tail_recursion_label_list;
 271
 272 extern struct obstack flow_obstack;
 273
 274 /* Indexed by n, gives number of basic block that  (REG n) is used in.
 275    If the value is REG_BLOCK_GLOBAL (-2),
 276    it means (REG n) is used in more than one basic block.
 277    REG_BLOCK_UNKNOWN (-1) means it hasn't been seen yet so we don't know.
 278    This information remains valid for the rest of the compilation
 279    of the current function; it is used to control register allocation.  */
 280
 281 #define REG_BLOCK_UNKNOWN -1
 282 #define REG_BLOCK_GLOBAL -2
 283
 284 #define REG_BASIC_BLOCK(N) (VARRAY_REG (reg_n_info, N)->basic_block)
 285 \f
 286 /* Stuff for recording basic block info.  */
 287
 288 #define BLOCK_HEAD(B)      (BASIC_BLOCK (B)->head)
 289 #define BLOCK_END(B)       (BASIC_BLOCK (B)->end)
 290
 291 #define BLOCK_HEAD_TREE(B) (BASIC_BLOCK (B)->head_tree)
 292 #define BLOCK_END_TREE(B) (BASIC_BLOCK (B)->end_tree)
 293
 294 /* Special block numbers [markers] for entry and exit.  */
 295 #define ENTRY_BLOCK (-1)
 296 #define EXIT_BLOCK (-2)
 297
 298 /* Special block number not valid for any block.  */
 299 #define INVALID_BLOCK (-3)
 300
 301 /* Similarly, block pointers for the edge list.  */
 302 extern struct basic_block_def entry_exit_blocks[2];
 303 #define ENTRY_BLOCK_PTR (&entry_exit_blocks[0])
 304 #define EXIT_BLOCK_PTR  (&entry_exit_blocks[1])
 305
 306 extern varray_type basic_block_for_insn;
 307 #define BLOCK_FOR_INSN(INSN)  VARRAY_BB (basic_block_for_insn, INSN_UID (INSN))
 308 #define BLOCK_NUM(INSN)       (BLOCK_FOR_INSN (INSN)->index + 0)
 309
 310 extern void compute_bb_for_insn         PARAMS ((int));
 311 extern void free_bb_for_insn            PARAMS ((void));
 312 extern void update_bb_for_insn          PARAMS ((basic_block));
 313 extern void set_block_for_insn          PARAMS ((rtx, basic_block));
 314
 315 extern void free_basic_block_vars       PARAMS ((int));
 316
 317 extern edge split_block                 PARAMS ((basic_block, rtx));
 318 extern basic_block split_edge           PARAMS ((edge));
 319 extern void insert_insn_on_edge         PARAMS ((rtx, edge));
 320
 321 extern void commit_edge_insertions      PARAMS ((void));
 322 extern void commit_edge_insertions_watch_calls  PARAMS ((void));
 323
 324 extern void remove_fake_edges           PARAMS ((void));
 325 extern void add_noreturn_fake_exit_edges        PARAMS ((void));
 326 extern void connect_infinite_loops_to_exit      PARAMS ((void));
 327 extern int flow_call_edges_add          PARAMS ((sbitmap));
 328 extern edge cached_make_edge            PARAMS ((sbitmap *, basic_block,
 329                                                  basic_block, int));
 330 extern edge make_edge                   PARAMS ((basic_block,
 331                                                  basic_block, int));
 332 extern edge make_single_succ_edge       PARAMS ((basic_block,
 333                                                  basic_block, int));
 334 extern void remove_edge                 PARAMS ((edge));
 335 extern void redirect_edge_succ          PARAMS ((edge, basic_block));
 336 extern edge redirect_edge_succ_nodup    PARAMS ((edge, basic_block));
 337 extern void redirect_edge_pred          PARAMS ((edge, basic_block));
 338 extern basic_block create_basic_block_structure PARAMS ((int, rtx, rtx, rtx, basic_block));
 339 extern basic_block create_basic_block   PARAMS ((rtx, rtx, basic_block));
 340 extern int flow_delete_block            PARAMS ((basic_block));
 341 extern int flow_delete_block_noexpunge  PARAMS ((basic_block));
 342 extern void clear_bb_flags              PARAMS ((void));
 343 extern void merge_blocks_nomove         PARAMS ((basic_block, basic_block));
 344 extern void tidy_fallthru_edge          PARAMS ((edge, basic_block,
 345                                                  basic_block));
 346 extern void tidy_fallthru_edges         PARAMS ((void));
 347 extern void flow_reverse_top_sort_order_compute PARAMS ((int *));
 348 extern int flow_depth_first_order_compute       PARAMS ((int *, int *));
 349 extern void flow_preorder_transversal_compute   PARAMS ((int *));
 350 extern void dump_edge_info              PARAMS ((FILE *, edge, int));
 351 extern void clear_edges                 PARAMS ((void));
 352 extern void mark_critical_edges         PARAMS ((void));
 353 extern rtx first_insn_after_basic_block_note    PARAMS ((basic_block));
 354
 355 /* Structure to hold information for each natural loop.  */
 356 struct loop
 357 {
 358   /* Index into loops array.  */
 359   int num;
 360
 361   /* Basic block of loop header.  */
 362   basic_block header;
 363
 364   /* Basic block of loop latch.  */
 365   basic_block latch;
 366
 367   /* Basic block of loop pre-header or NULL if it does not exist.  */
 368   basic_block pre_header;
 369
 370   /* Array of edges along the pre-header extended basic block trace.
 371      The source of the first edge is the root node of pre-header
 372      extended basic block, if it exists.  */
 373   edge *pre_header_edges;
 374
 375   /* Number of edges along the pre_header extended basic block trace.  */
 376   int num_pre_header_edges;
 377
 378   /* The first block in the loop.  This is not necessarily the same as
 379      the loop header.  */
 380   basic_block first;
 381
 382   /* The last block in the loop.  This is not necessarily the same as
 383      the loop latch.  */
 384   basic_block last;
 385
 386   /* Bitmap of blocks contained within the loop.  */
 387   sbitmap nodes;
 388
 389   /* Number of blocks contained within the loop.  */
 390   int num_nodes;
 391
 392   /* Array of edges that enter the loop.  */
 393   edge *entry_edges;
 394
 395   /* Number of edges that enter the loop.  */
 396   int num_entries;
 397
 398   /* Array of edges that exit the loop.  */
 399   edge *exit_edges;
 400
 401   /* Number of edges that exit the loop.  */
 402   int num_exits;
 403
 404   /* Bitmap of blocks that dominate all exits of the loop.  */
 405   sbitmap exits_doms;
 406
 407   /* The loop nesting depth.  */
 408   int depth;
 409
 410   /* Superloops of the loop.  */
 411   struct loop **pred;
 412
 413   /* The height of the loop (enclosed loop levels) within the loop
 414      hierarchy tree.  */
 415   int level;
 416
 417   /* The outer (parent) loop or NULL if outermost loop.  */
 418   struct loop *outer;
 419
 420   /* The first inner (child) loop or NULL if innermost loop.  */
 421   struct loop *inner;
 422
 423   /* Link to the next (sibling) loop.  */
 424   struct loop *next;
 425
 426   /* Non-zero if the loop is invalid (e.g., contains setjmp.).  */
 427   int invalid;
 428
 429   /* Auxiliary info specific to a pass.  */
 430   void *aux;
 431
 432   /* The following are currently used by loop.c but they are likely to
 433      disappear as loop.c is converted to use the CFG.  */
 434
 435   /* Non-zero if the loop has a NOTE_INSN_LOOP_VTOP.  */
 436   rtx vtop;
 437
 438   /* Non-zero if the loop has a NOTE_INSN_LOOP_CONT.
 439      A continue statement will generate a branch to NEXT_INSN (cont).  */
 440   rtx cont;
 441
 442   /* The dominator of cont.  */
 443   rtx cont_dominator;
 444
 445   /* The NOTE_INSN_LOOP_BEG.  */
 446   rtx start;
 447
 448   /* The NOTE_INSN_LOOP_END.  */
 449   rtx end;
 450
 451   /* For a rotated loop that is entered near the bottom,
 452      this is the label at the top.  Otherwise it is zero.  */
 453   rtx top;
 454
 455   /* Place in the loop where control enters.  */
 456   rtx scan_start;
 457
 458   /* The position where to sink insns out of the loop.  */
 459   rtx sink;
 460
 461   /* List of all LABEL_REFs which refer to code labels outside the
 462      loop.  Used by routines that need to know all loop exits, such as
 463      final_biv_value and final_giv_value.
 464
 465      This does not include loop exits due to return instructions.
 466      This is because all bivs and givs are pseudos, and hence must be
 467      dead after a return, so the presense of a return does not affect
 468      any of the optimizations that use this info.  It is simpler to
 469      just not include return instructions on this list.  */
 470   rtx exit_labels;
 471
 472   /* The number of LABEL_REFs on exit_labels for this loop and all
 473      loops nested inside it.  */
 474   int exit_count;
 475 };
 476
 477
 478 /* Structure to hold CFG information about natural loops within a function.  */
 479 struct loops
 480 {
 481   /* Number of natural loops in the function.  */
 482   int num;
 483
 484   /* Maxium nested loop level in the function.  */
 485   int levels;
 486
 487   /* Array of natural loop descriptors (scanning this array in reverse order
 488      will find the inner loops before their enclosing outer loops).  */
 489   struct loop *array;
 490
 491   /* The above array is unused in new loop infrastructure and is kept only for
 492      purposes of the old loop optimizer.  Instead we store just pointers to
 493      loops here.  */
 494   struct loop **parray;
 495
 496   /* Pointer to root of loop heirachy tree.  */
 497   struct loop *tree_root;
 498
 499   /* Information derived from the CFG.  */
 500   struct cfg
 501   {
 502     /* The bitmap vector of dominators or NULL if not computed.  */
 503     sbitmap *dom;
 504
 505     /* The ordering of the basic blocks in a depth first search.  */
 506     int *dfs_order;
 507
 508     /* The reverse completion ordering of the basic blocks found in a
 509        depth first search.  */
 510     int *rc_order;
 511   } cfg;
 512
 513   /* Headers shared by multiple loops that should be merged.  */
 514   sbitmap shared_headers;
 515 };
 516
 517 extern int flow_loops_find PARAMS ((struct loops *, int flags));
 518 extern int flow_loops_update PARAMS ((struct loops *, int flags));
 519 extern void flow_loops_free PARAMS ((struct loops *));
 520 extern void flow_loops_dump PARAMS ((const struct loops *, FILE *,
 521                                      void (*)(const struct loop *,
 522                                               FILE *, int), int));
 523 extern void flow_loop_dump PARAMS ((const struct loop *, FILE *,
 524                                     void (*)(const struct loop *,
 525                                              FILE *, int), int));
 526 extern int flow_loop_scan PARAMS ((struct loops *, struct loop *, int));
 527 extern void flow_loop_tree_node_add PARAMS ((struct loop *, struct loop *));
 528 extern void flow_loop_tree_node_remove PARAMS ((struct loop *));
 529
 530 /* This structure maintains an edge list vector.  */
 531 struct edge_list
 532 {
 533   int num_blocks;
 534   int num_edges;
 535   edge *index_to_edge;
 536 };
 537
 538 /* This is the value which indicates no edge is present.  */
 539 #define EDGE_INDEX_NO_EDGE      -1
 540
 541 /* EDGE_INDEX returns an integer index for an edge, or EDGE_INDEX_NO_EDGE
 542    if there is no edge between the 2 basic blocks.  */
 543 #define EDGE_INDEX(el, pred, succ) (find_edge_index ((el), (pred), (succ)))
 544
 545 /* INDEX_EDGE_PRED_BB and INDEX_EDGE_SUCC_BB return a pointer to the basic
 546    block which is either the pred or succ end of the indexed edge.  */
 547 #define INDEX_EDGE_PRED_BB(el, index)   ((el)->index_to_edge[(index)]->src)
 548 #define INDEX_EDGE_SUCC_BB(el, index)   ((el)->index_to_edge[(index)]->dest)
 549
 550 /* INDEX_EDGE returns a pointer to the edge.  */
 551 #define INDEX_EDGE(el, index)           ((el)->index_to_edge[(index)])
 552
 553 /* Number of edges in the compressed edge list.  */
 554 #define NUM_EDGES(el)                   ((el)->num_edges)
 555
 556 /* BB is assumed to contain conditional jump.  Return the fallthru edge.  */
 557 #define FALLTHRU_EDGE(bb)               ((bb)->succ->flags & EDGE_FALLTHRU \
 558                                          ? (bb)->succ : (bb)->succ->succ_next)
 559
 560 /* BB is assumed to contain conditional jump.  Return the branch edge.  */
 561 #define BRANCH_EDGE(bb)                 ((bb)->succ->flags & EDGE_FALLTHRU \
 562                                          ? (bb)->succ->succ_next : (bb)->succ)
 563
 564 /* Return expected execution frequency of the edge E.  */
 565 #define EDGE_FREQUENCY(e)               (((e)->src->frequency \
 566                                           * (e)->probability \
 567                                           + REG_BR_PROB_BASE / 2) \
 568                                          / REG_BR_PROB_BASE)
 569
 570 /* Return nonzero if edge is critical.  */
 571 #define EDGE_CRITICAL_P(e)              ((e)->src->succ->succ_next \
 572                                          && (e)->dest->pred->pred_next)
 573
 574 struct edge_list * create_edge_list     PARAMS ((void));
 575 void free_edge_list                     PARAMS ((struct edge_list *));
 576 void print_edge_list                    PARAMS ((FILE *, struct edge_list *));
 577 void verify_edge_list                   PARAMS ((FILE *, struct edge_list *));
 578 int find_edge_index                     PARAMS ((struct edge_list *,
 579                                                  basic_block, basic_block));
 580
 581
 582 enum update_life_extent
 583 {
 584   UPDATE_LIFE_LOCAL = 0,
 585   UPDATE_LIFE_GLOBAL = 1,
 586   UPDATE_LIFE_GLOBAL_RM_NOTES = 2
 587 };
 588
 589 /* Flags for life_analysis and update_life_info.  */
 590
 591 #define PROP_DEATH_NOTES        1       /* Create DEAD and UNUSED notes.  */
 592 #define PROP_LOG_LINKS          2       /* Create LOG_LINKS.  */
 593 #define PROP_REG_INFO           4       /* Update regs_ever_live et al.  */
 594 #define PROP_KILL_DEAD_CODE     8       /* Remove dead code.  */
 595 #define PROP_SCAN_DEAD_CODE     16      /* Scan for dead code.  */
 596 #define PROP_ALLOW_CFG_CHANGES  32      /* Allow the CFG to be changed
 597                                            by dead code removal.  */
 598 #define PROP_AUTOINC            64      /* Create autoinc mem references.  */
 599 #define PROP_EQUAL_NOTES        128     /* Take into account REG_EQUAL notes.  */
 600 #define PROP_SCAN_DEAD_STORES   256     /* Scan for dead code.  */
 601 #define PROP_FINAL              (PROP_DEATH_NOTES | PROP_LOG_LINKS  \
 602                                  | PROP_REG_INFO | PROP_KILL_DEAD_CODE  \
 603                                  | PROP_SCAN_DEAD_CODE | PROP_AUTOINC \
 604                                  | PROP_ALLOW_CFG_CHANGES \
 605                                  | PROP_SCAN_DEAD_STORES)
 606
 607 #define CLEANUP_EXPENSIVE       1       /* Do relativly expensive optimizations
 608                                            except for edge forwarding */
 609 #define CLEANUP_CROSSJUMP       2       /* Do crossjumping.  */
 610 #define CLEANUP_POST_REGSTACK   4       /* We run after reg-stack and need
 611                                            to care REG_DEAD notes.  */
 612 #define CLEANUP_PRE_SIBCALL     8       /* Do not get confused by code hidden
 613                                            inside call_placeholders..  */
 614 #define CLEANUP_PRE_LOOP        16      /* Take care to preserve syntactic loop
 615                                            notes.  */
 616 #define CLEANUP_UPDATE_LIFE     32      /* Keep life information up to date.  */
 617 #define CLEANUP_THREADING       64      /* Do jump threading.  */
 618 #define CLEANUP_NO_INSN_DEL     128     /* Do not try to delete trivially dead
 619                                            insns.  */
 620 /* Flags for loop discovery.  */
 621
 622 #define LOOP_TREE               1       /* Build loop hierarchy tree.  */
 623 #define LOOP_PRE_HEADER         2       /* Analyse loop pre-header.  */
 624 #define LOOP_ENTRY_EDGES        4       /* Find entry edges.  */
 625 #define LOOP_EXIT_EDGES         8       /* Find exit edges.  */
 626 #define LOOP_EDGES              (LOOP_ENTRY_EDGES | LOOP_EXIT_EDGES)
 627 #define LOOP_ALL               15       /* All of the above  */
 628
 629 extern void life_analysis       PARAMS ((rtx, FILE *, int));
 630 extern int update_life_info     PARAMS ((sbitmap, enum update_life_extent,
 631                                          int));
 632 extern int update_life_info_in_dirty_blocks PARAMS ((enum update_life_extent,
 633                                                       int));
 634 extern int count_or_remove_death_notes  PARAMS ((sbitmap, int));
 635 extern int propagate_block      PARAMS ((basic_block, regset, regset, regset,
 636                                          int));
 637
 638 struct propagate_block_info;
 639 extern rtx propagate_one_insn   PARAMS ((struct propagate_block_info *, rtx));
 640 extern struct propagate_block_info *init_propagate_block_info
 641   PARAMS ((basic_block, regset, regset, regset, int));
 642 extern void free_propagate_block_info PARAMS ((struct propagate_block_info *));
 643
 644 /* In lcm.c */
 645 extern struct edge_list *pre_edge_lcm   PARAMS ((FILE *, int, sbitmap *,
 646                                                  sbitmap *, sbitmap *,
 647                                                  sbitmap *, sbitmap **,
 648                                                  sbitmap **));
 649 extern struct edge_list *pre_edge_rev_lcm PARAMS ((FILE *, int, sbitmap *,
 650                                                    sbitmap *, sbitmap *,
 651                                                    sbitmap *, sbitmap **,
 652                                                    sbitmap **));
 653 extern void compute_available           PARAMS ((sbitmap *, sbitmap *,
 654                                                  sbitmap *, sbitmap *));
 655 extern int optimize_mode_switching      PARAMS ((FILE *));
 656
 657 /* In emit-rtl.c.  */
 658 extern rtx emit_block_insn_after        PARAMS ((rtx, rtx, basic_block));
 659 extern rtx emit_block_insn_before       PARAMS ((rtx, rtx, basic_block));
 660
 661 /* In predict.c */
 662 extern void estimate_probability        PARAMS ((struct loops *));
 663 extern void note_prediction_to_br_prob  PARAMS ((void));
 664 extern void expected_value_to_br_prob   PARAMS ((void));
 665 extern void note_prediction_to_br_prob  PARAMS ((void));
 666 extern bool maybe_hot_bb_p              PARAMS ((basic_block));
 667 extern bool probably_cold_bb_p          PARAMS ((basic_block));
 668 extern bool probably_never_executed_bb_p PARAMS ((basic_block));
 669
 670 /* In flow.c */
 671 extern void init_flow                   PARAMS ((void));
 672 extern void reorder_basic_blocks        PARAMS ((void));
 673 extern void dump_bb                     PARAMS ((basic_block, FILE *));
 674 extern void debug_bb                    PARAMS ((basic_block));
 675 extern void debug_bb_n                  PARAMS ((int));
 676 extern void dump_regset                 PARAMS ((regset, FILE *));
 677 extern void debug_regset                PARAMS ((regset));
 678 extern void allocate_reg_life_data      PARAMS ((void));
 679 extern void allocate_bb_life_data       PARAMS ((void));
 680 extern void expunge_block               PARAMS ((basic_block));
 681 extern void link_block                  PARAMS ((basic_block, basic_block));
 682 extern void unlink_block                PARAMS ((basic_block));
 683 extern void compact_blocks              PARAMS ((void));
 684 extern basic_block alloc_block          PARAMS ((void));
 685 extern void find_unreachable_blocks     PARAMS ((void));
 686 extern int delete_noop_moves            PARAMS ((rtx));
 687 extern basic_block redirect_edge_and_branch_force PARAMS ((edge, basic_block));
 688 extern basic_block force_nonfallthru    PARAMS ((edge));
 689 extern bool redirect_edge_and_branch    PARAMS ((edge, basic_block));
 690 extern rtx block_label                  PARAMS ((basic_block));
 691 extern bool forwarder_block_p           PARAMS ((basic_block));
 692 extern bool purge_all_dead_edges        PARAMS ((int));
 693 extern bool purge_dead_edges            PARAMS ((basic_block));
 694 extern void find_sub_basic_blocks       PARAMS ((basic_block));
 695 extern void find_many_sub_basic_blocks  PARAMS ((sbitmap));
 696 extern bool can_fallthru                PARAMS ((basic_block, basic_block));
 697 extern void flow_nodes_print            PARAMS ((const char *, const sbitmap,
 698                                                  FILE *));
 699 extern void flow_edge_list_print        PARAMS ((const char *, const edge *,
 700                                                  int, FILE *));
 701 extern void alloc_aux_for_block         PARAMS ((basic_block, int));
 702 extern void alloc_aux_for_blocks        PARAMS ((int));
 703 extern void clear_aux_for_blocks        PARAMS ((void));
 704 extern void free_aux_for_blocks         PARAMS ((void));
 705 extern void alloc_aux_for_edge          PARAMS ((edge, int));
 706 extern void alloc_aux_for_edges         PARAMS ((int));
 707 extern void clear_aux_for_edges         PARAMS ((void));
 708 extern void free_aux_for_edges          PARAMS ((void));
 709
 710 /* This function is always defined so it can be called from the
 711    debugger, and it is declared extern so we don't get warnings about
 712    it being unused.  */
 713 extern void verify_flow_info            PARAMS ((void));
 714 extern bool flow_loop_outside_edge_p    PARAMS ((const struct loop *, edge));
 715 extern bool flow_loop_nested_p PARAMS ((const struct loop *, const struct loop *));
 716 extern bool flow_bb_inside_loop_p       PARAMS ((const struct loop *, basic_block));
 717 extern basic_block *get_loop_body       PARAMS ((const struct loop *));
 718 extern int dfs_enumerate_from           PARAMS ((basic_block, int,
 719                                          bool (*)(basic_block, void *),
 720                                          basic_block *, int, void *));
 721
 722 extern edge loop_preheader_edge PARAMS ((struct loop *));
 723 extern edge loop_latch_edge PARAMS ((struct loop *));
 724
 725 extern void add_bb_to_loop PARAMS ((basic_block, struct loop *));
 726 extern void remove_bb_from_loops PARAMS ((basic_block));
 727 extern struct loop * find_common_loop PARAMS ((struct loop *, struct loop *));
 728
 729 extern void verify_loop_structure PARAMS ((struct loops *, int));
 730 #define VLS_EXPECT_PREHEADERS 1
 731 #define VLS_EXPECT_SIMPLE_LATCHES 2
 732
 733 typedef struct conflict_graph_def *conflict_graph;
 734
 735 /* Callback function when enumerating conflicts.  The arguments are
 736    the smaller and larger regno in the conflict.  Returns zero if
 737    enumeration is to continue, non-zero to halt enumeration.  */
 738 typedef int (*conflict_graph_enum_fn) PARAMS ((int, int, void *));
 739
 740
 741 /* Prototypes of operations on conflict graphs.  */
 742
 743 extern conflict_graph conflict_graph_new
 744                                         PARAMS ((int));
 745 extern void conflict_graph_delete       PARAMS ((conflict_graph));
 746 extern int conflict_graph_add           PARAMS ((conflict_graph,
 747                                                  int, int));
 748 extern int conflict_graph_conflict_p    PARAMS ((conflict_graph,
 749                                                  int, int));
 750 extern void conflict_graph_enum         PARAMS ((conflict_graph, int,
 751                                                  conflict_graph_enum_fn,
 752                                                  void *));
 753 extern void conflict_graph_merge_regs   PARAMS ((conflict_graph, int,
 754                                                  int));
 755 extern void conflict_graph_print        PARAMS ((conflict_graph, FILE*));
 756 extern conflict_graph conflict_graph_compute
 757                                         PARAMS ((regset,
 758                                                  partition));
 759 extern bool mark_dfs_back_edges         PARAMS ((void));
 760 extern void set_edge_can_fallthru_flag  PARAMS ((void));
 761 extern void update_br_prob_note         PARAMS ((basic_block));
 762 extern void fixup_abnormal_edges        PARAMS ((void));
 763 extern bool can_hoist_insn_p            PARAMS ((rtx, rtx, regset));
 764 extern rtx hoist_insn_after             PARAMS ((rtx, rtx, rtx, rtx));
 765 extern rtx hoist_insn_to_edge           PARAMS ((rtx, edge, rtx, rtx));
 766
 767 /* In dominance.c */
 768
 769 enum cdi_direction
 770 {
 771   CDI_DOMINATORS,
 772   CDI_POST_DOMINATORS
 773 };
 774
 775 extern void calculate_dominance_info    PARAMS ((int *, sbitmap *,
 776                                                  enum cdi_direction));
 777
 778 #endif /* GCC_BASIC_BLOCK_H */