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   /* Expected number of executions: calculated in profile.c.  */
 216   gcov_type count;
 217
 218   /* Expected frequency.  Normalized to be in range 0 to BB_FREQ_MAX.  */
 219   int frequency;
 220
 221   /* Various flags.  See BB_* below.  */
 222   int flags;
 223 } *basic_block;
 224
 225 #define BB_FREQ_MAX 10000
 226
 227 /* Masks for basic_block.flags.  */
 228 #define BB_DIRTY                1
 229 #define BB_NEW                  2
 230 #define BB_REACHABLE            4
 231
 232 /* Number of basic blocks in the current function.  */
 233
 234 extern int n_basic_blocks;
 235
 236 /* Number of edges in the current function.  */
 237
 238 extern int n_edges;
 239
 240 /* Index by basic block number, get basic block struct info.  */
 241
 242 extern varray_type basic_block_info;
 243
 244 #define BASIC_BLOCK(N)  (VARRAY_BB (basic_block_info, (N)))
 245
 246 /* For iterating over basic blocks.  */
 247 #define FOR_BB_BETWEEN(BB, FROM, TO, DIR) \
 248   for (BB = FROM; BB != TO; BB = BB->DIR)
 249
 250 #define FOR_EACH_BB(BB) \
 251   FOR_BB_BETWEEN (BB, ENTRY_BLOCK_PTR->next_bb, EXIT_BLOCK_PTR, next_bb)
 252
 253 #define FOR_EACH_BB_REVERSE(BB) \
 254   FOR_BB_BETWEEN (BB, EXIT_BLOCK_PTR->prev_bb, ENTRY_BLOCK_PTR, prev_bb)
 255
 256 /* What registers are live at the setjmp call.  */
 257
 258 extern regset regs_live_at_setjmp;
 259
 260 /* Special labels found during CFG build.  */
 261
 262 extern rtx label_value_list, tail_recursion_label_list;
 263
 264 extern struct obstack flow_obstack;
 265
 266 /* Indexed by n, gives number of basic block that  (REG n) is used in.
 267    If the value is REG_BLOCK_GLOBAL (-2),
 268    it means (REG n) is used in more than one basic block.
 269    REG_BLOCK_UNKNOWN (-1) means it hasn't been seen yet so we don't know.
 270    This information remains valid for the rest of the compilation
 271    of the current function; it is used to control register allocation.  */
 272
 273 #define REG_BLOCK_UNKNOWN -1
 274 #define REG_BLOCK_GLOBAL -2
 275
 276 #define REG_BASIC_BLOCK(N) (VARRAY_REG (reg_n_info, N)->basic_block)
 277 \f
 278 /* Stuff for recording basic block info.  */
 279
 280 #define BLOCK_HEAD(B)      (BASIC_BLOCK (B)->head)
 281 #define BLOCK_END(B)       (BASIC_BLOCK (B)->end)
 282
 283 #define BLOCK_HEAD_TREE(B) (BASIC_BLOCK (B)->head_tree)
 284 #define BLOCK_END_TREE(B) (BASIC_BLOCK (B)->end_tree)
 285
 286 /* Special block numbers [markers] for entry and exit.  */
 287 #define ENTRY_BLOCK (-1)
 288 #define EXIT_BLOCK (-2)
 289
 290 /* Special block number not valid for any block.  */
 291 #define INVALID_BLOCK (-3)
 292
 293 /* Similarly, block pointers for the edge list.  */
 294 extern struct basic_block_def entry_exit_blocks[2];
 295 #define ENTRY_BLOCK_PTR (&entry_exit_blocks[0])
 296 #define EXIT_BLOCK_PTR  (&entry_exit_blocks[1])
 297
 298 extern varray_type basic_block_for_insn;
 299 #define BLOCK_FOR_INSN(INSN)  VARRAY_BB (basic_block_for_insn, INSN_UID (INSN))
 300 #define BLOCK_NUM(INSN)       (BLOCK_FOR_INSN (INSN)->index + 0)
 301
 302 extern void compute_bb_for_insn         PARAMS ((int));
 303 extern void free_bb_for_insn            PARAMS ((void));
 304 extern void update_bb_for_insn          PARAMS ((basic_block));
 305 extern void set_block_for_insn          PARAMS ((rtx, basic_block));
 306
 307 extern void free_basic_block_vars       PARAMS ((int));
 308
 309 extern edge split_block                 PARAMS ((basic_block, rtx));
 310 extern basic_block split_edge           PARAMS ((edge));
 311 extern void insert_insn_on_edge         PARAMS ((rtx, edge));
 312
 313 extern void commit_edge_insertions      PARAMS ((void));
 314 extern void commit_edge_insertions_watch_calls  PARAMS ((void));
 315
 316 extern void remove_fake_edges           PARAMS ((void));
 317 extern void add_noreturn_fake_exit_edges        PARAMS ((void));
 318 extern void connect_infinite_loops_to_exit      PARAMS ((void));
 319 extern int flow_call_edges_add          PARAMS ((sbitmap));
 320 extern edge cached_make_edge            PARAMS ((sbitmap *, basic_block,
 321                                                  basic_block, int));
 322 extern edge make_edge                   PARAMS ((basic_block,
 323                                                  basic_block, int));
 324 extern edge make_single_succ_edge       PARAMS ((basic_block,
 325                                                  basic_block, int));
 326 extern void remove_edge                 PARAMS ((edge));
 327 extern void redirect_edge_succ          PARAMS ((edge, basic_block));
 328 extern edge redirect_edge_succ_nodup    PARAMS ((edge, basic_block));
 329 extern void redirect_edge_pred          PARAMS ((edge, basic_block));
 330 extern basic_block create_basic_block_structure PARAMS ((int, rtx, rtx, rtx, basic_block));
 331 extern basic_block create_basic_block   PARAMS ((rtx, rtx, basic_block));
 332 extern int flow_delete_block            PARAMS ((basic_block));
 333 extern int flow_delete_block_noexpunge  PARAMS ((basic_block));
 334 extern void clear_bb_flags              PARAMS ((void));
 335 extern void merge_blocks_nomove         PARAMS ((basic_block, basic_block));
 336 extern void tidy_fallthru_edge          PARAMS ((edge, basic_block,
 337                                                  basic_block));
 338 extern void tidy_fallthru_edges         PARAMS ((void));
 339 extern void flow_reverse_top_sort_order_compute PARAMS ((int *));
 340 extern int flow_depth_first_order_compute       PARAMS ((int *, int *));
 341 extern void flow_preorder_transversal_compute   PARAMS ((int *));
 342 extern void dump_edge_info              PARAMS ((FILE *, edge, int));
 343 extern void clear_edges                 PARAMS ((void));
 344 extern void mark_critical_edges         PARAMS ((void));
 345 extern rtx first_insn_after_basic_block_note    PARAMS ((basic_block));
 346
 347 /* Structure to hold information for each natural loop.  */
 348 struct loop
 349 {
 350   /* Index into loops array.  */
 351   int num;
 352
 353   /* Basic block of loop header.  */
 354   basic_block header;
 355
 356   /* Basic block of loop latch.  */
 357   basic_block latch;
 358
 359   /* Basic block of loop pre-header or NULL if it does not exist.  */
 360   basic_block pre_header;
 361
 362   /* Array of edges along the pre-header extended basic block trace.
 363      The source of the first edge is the root node of pre-header
 364      extended basic block, if it exists.  */
 365   edge *pre_header_edges;
 366
 367   /* Number of edges along the pre_header extended basic block trace.  */
 368   int num_pre_header_edges;
 369
 370   /* The first block in the loop.  This is not necessarily the same as
 371      the loop header.  */
 372   basic_block first;
 373
 374   /* The last block in the loop.  This is not necessarily the same as
 375      the loop latch.  */
 376   basic_block last;
 377
 378   /* Bitmap of blocks contained within the loop.  */
 379   sbitmap nodes;
 380
 381   /* Number of blocks contained within the loop.  */
 382   int num_nodes;
 383
 384   /* Array of edges that enter the loop.  */
 385   edge *entry_edges;
 386
 387   /* Number of edges that enter the loop.  */
 388   int num_entries;
 389
 390   /* Array of edges that exit the loop.  */
 391   edge *exit_edges;
 392
 393   /* Number of edges that exit the loop.  */
 394   int num_exits;
 395
 396   /* Bitmap of blocks that dominate all exits of the loop.  */
 397   sbitmap exits_doms;
 398
 399   /* The loop nesting depth.  */
 400   int depth;
 401
 402   /* The height of the loop (enclosed loop levels) within the loop
 403      hierarchy tree.  */
 404   int level;
 405
 406   /* The outer (parent) loop or NULL if outermost loop.  */
 407   struct loop *outer;
 408
 409   /* The first inner (child) loop or NULL if innermost loop.  */
 410   struct loop *inner;
 411
 412   /* Link to the next (sibling) loop.  */
 413   struct loop *next;
 414
 415   /* Non-zero if the loop shares a header with another loop.  */
 416   int shared;
 417
 418   /* Non-zero if the loop is invalid (e.g., contains setjmp.).  */
 419   int invalid;
 420
 421   /* Auxiliary info specific to a pass.  */
 422   void *aux;
 423
 424   /* The following are currently used by loop.c but they are likely to
 425      disappear as loop.c is converted to use the CFG.  */
 426
 427   /* Non-zero if the loop has a NOTE_INSN_LOOP_VTOP.  */
 428   rtx vtop;
 429
 430   /* Non-zero if the loop has a NOTE_INSN_LOOP_CONT.
 431      A continue statement will generate a branch to NEXT_INSN (cont).  */
 432   rtx cont;
 433
 434   /* The dominator of cont.  */
 435   rtx cont_dominator;
 436
 437   /* The NOTE_INSN_LOOP_BEG.  */
 438   rtx start;
 439
 440   /* The NOTE_INSN_LOOP_END.  */
 441   rtx end;
 442
 443   /* For a rotated loop that is entered near the bottom,
 444      this is the label at the top.  Otherwise it is zero.  */
 445   rtx top;
 446
 447   /* Place in the loop where control enters.  */
 448   rtx scan_start;
 449
 450   /* The position where to sink insns out of the loop.  */
 451   rtx sink;
 452
 453   /* List of all LABEL_REFs which refer to code labels outside the
 454      loop.  Used by routines that need to know all loop exits, such as
 455      final_biv_value and final_giv_value.
 456
 457      This does not include loop exits due to return instructions.
 458      This is because all bivs and givs are pseudos, and hence must be
 459      dead after a return, so the presense of a return does not affect
 460      any of the optimizations that use this info.  It is simpler to
 461      just not include return instructions on this list.  */
 462   rtx exit_labels;
 463
 464   /* The number of LABEL_REFs on exit_labels for this loop and all
 465      loops nested inside it.  */
 466   int exit_count;
 467 };
 468
 469
 470 /* Structure to hold CFG information about natural loops within a function.  */
 471 struct loops
 472 {
 473   /* Number of natural loops in the function.  */
 474   int num;
 475
 476   /* Maxium nested loop level in the function.  */
 477   int levels;
 478
 479   /* Array of natural loop descriptors (scanning this array in reverse order
 480      will find the inner loops before their enclosing outer loops).  */
 481   struct loop *array;
 482
 483   /* Pointer to root of loop heirachy tree.  */
 484   struct loop *tree_root;
 485
 486   /* Information derived from the CFG.  */
 487   struct cfg
 488   {
 489     /* The bitmap vector of dominators or NULL if not computed.  */
 490     sbitmap *dom;
 491
 492     /* The ordering of the basic blocks in a depth first search.  */
 493     int *dfs_order;
 494
 495     /* The reverse completion ordering of the basic blocks found in a
 496        depth first search.  */
 497     int *rc_order;
 498   } cfg;
 499
 500   /* Headers shared by multiple loops that should be merged.  */
 501   sbitmap shared_headers;
 502 };
 503
 504 extern int flow_loops_find PARAMS ((struct loops *, int flags));
 505 extern int flow_loops_update PARAMS ((struct loops *, int flags));
 506 extern void flow_loops_free PARAMS ((struct loops *));
 507 extern void flow_loops_dump PARAMS ((const struct loops *, FILE *,
 508                                      void (*)(const struct loop *,
 509                                               FILE *, int), int));
 510 extern void flow_loop_dump PARAMS ((const struct loop *, FILE *,
 511                                     void (*)(const struct loop *,
 512                                              FILE *, int), int));
 513 extern int flow_loop_scan PARAMS ((struct loops *, struct loop *, int));
 514
 515 /* This structure maintains an edge list vector.  */
 516 struct edge_list
 517 {
 518   int num_blocks;
 519   int num_edges;
 520   edge *index_to_edge;
 521 };
 522
 523 /* This is the value which indicates no edge is present.  */
 524 #define EDGE_INDEX_NO_EDGE      -1
 525
 526 /* EDGE_INDEX returns an integer index for an edge, or EDGE_INDEX_NO_EDGE
 527    if there is no edge between the 2 basic blocks.  */
 528 #define EDGE_INDEX(el, pred, succ) (find_edge_index ((el), (pred), (succ)))
 529
 530 /* INDEX_EDGE_PRED_BB and INDEX_EDGE_SUCC_BB return a pointer to the basic
 531    block which is either the pred or succ end of the indexed edge.  */
 532 #define INDEX_EDGE_PRED_BB(el, index)   ((el)->index_to_edge[(index)]->src)
 533 #define INDEX_EDGE_SUCC_BB(el, index)   ((el)->index_to_edge[(index)]->dest)
 534
 535 /* INDEX_EDGE returns a pointer to the edge.  */
 536 #define INDEX_EDGE(el, index)           ((el)->index_to_edge[(index)])
 537
 538 /* Number of edges in the compressed edge list.  */
 539 #define NUM_EDGES(el)                   ((el)->num_edges)
 540
 541 /* BB is assumed to contain conditional jump.  Return the fallthru edge.  */
 542 #define FALLTHRU_EDGE(bb)               ((bb)->succ->flags & EDGE_FALLTHRU \
 543                                          ? (bb)->succ : (bb)->succ->succ_next)
 544
 545 /* BB is assumed to contain conditional jump.  Return the branch edge.  */
 546 #define BRANCH_EDGE(bb)                 ((bb)->succ->flags & EDGE_FALLTHRU \
 547                                          ? (bb)->succ->succ_next : (bb)->succ)
 548
 549 /* Return expected execution frequency of the edge E.  */
 550 #define EDGE_FREQUENCY(e)               (((e)->src->frequency \
 551                                           * (e)->probability \
 552                                           + REG_BR_PROB_BASE / 2) \
 553                                          / REG_BR_PROB_BASE)
 554
 555 /* Return nonzero if edge is critical.  */
 556 #define EDGE_CRITICAL_P(e)              ((e)->src->succ->succ_next \
 557                                          && (e)->dest->pred->pred_next)
 558
 559 struct edge_list * create_edge_list     PARAMS ((void));
 560 void free_edge_list                     PARAMS ((struct edge_list *));
 561 void print_edge_list                    PARAMS ((FILE *, struct edge_list *));
 562 void verify_edge_list                   PARAMS ((FILE *, struct edge_list *));
 563 int find_edge_index                     PARAMS ((struct edge_list *,
 564                                                  basic_block, basic_block));
 565
 566
 567 enum update_life_extent
 568 {
 569   UPDATE_LIFE_LOCAL = 0,
 570   UPDATE_LIFE_GLOBAL = 1,
 571   UPDATE_LIFE_GLOBAL_RM_NOTES = 2
 572 };
 573
 574 /* Flags for life_analysis and update_life_info.  */
 575
 576 #define PROP_DEATH_NOTES        1       /* Create DEAD and UNUSED notes.  */
 577 #define PROP_LOG_LINKS          2       /* Create LOG_LINKS.  */
 578 #define PROP_REG_INFO           4       /* Update regs_ever_live et al.  */
 579 #define PROP_KILL_DEAD_CODE     8       /* Remove dead code.  */
 580 #define PROP_SCAN_DEAD_CODE     16      /* Scan for dead code.  */
 581 #define PROP_ALLOW_CFG_CHANGES  32      /* Allow the CFG to be changed
 582                                            by dead code removal.  */
 583 #define PROP_AUTOINC            64      /* Create autoinc mem references.  */
 584 #define PROP_EQUAL_NOTES        128     /* Take into account REG_EQUAL notes.  */
 585 #define PROP_FINAL              127     /* All of the above.  */
 586
 587 #define CLEANUP_EXPENSIVE       1       /* Do relativly expensive optimizations
 588                                            except for edge forwarding */
 589 #define CLEANUP_CROSSJUMP       2       /* Do crossjumping.  */
 590 #define CLEANUP_POST_REGSTACK   4       /* We run after reg-stack and need
 591                                            to care REG_DEAD notes.  */
 592 #define CLEANUP_PRE_SIBCALL     8       /* Do not get confused by code hidden
 593                                            inside call_placeholders..  */
 594 #define CLEANUP_PRE_LOOP        16      /* Take care to preserve syntactic loop
 595                                            notes.  */
 596 #define CLEANUP_UPDATE_LIFE     32      /* Keep life information up to date.  */
 597 #define CLEANUP_THREADING       64      /* Do jump threading.  */
 598 /* Flags for loop discovery.  */
 599
 600 #define LOOP_TREE               1       /* Build loop hierarchy tree.  */
 601 #define LOOP_PRE_HEADER         2       /* Analyse loop pre-header.  */
 602 #define LOOP_ENTRY_EDGES        4       /* Find entry edges.  */
 603 #define LOOP_EXIT_EDGES         8       /* Find exit edges.  */
 604 #define LOOP_EDGES              (LOOP_ENTRY_EDGES | LOOP_EXIT_EDGES)
 605 #define LOOP_EXITS_DOMS        16       /* Find nodes that dom. all exits.  */
 606 #define LOOP_ALL               31       /* All of the above  */
 607
 608 extern void life_analysis       PARAMS ((rtx, FILE *, int));
 609 extern int update_life_info     PARAMS ((sbitmap, enum update_life_extent,
 610                                          int));
 611 extern int update_life_info_in_dirty_blocks PARAMS ((enum update_life_extent,
 612                                                       int));
 613 extern int count_or_remove_death_notes  PARAMS ((sbitmap, int));
 614 extern int propagate_block      PARAMS ((basic_block, regset, regset, regset,
 615                                          int));
 616
 617 struct propagate_block_info;
 618 extern rtx propagate_one_insn   PARAMS ((struct propagate_block_info *, rtx));
 619 extern struct propagate_block_info *init_propagate_block_info
 620   PARAMS ((basic_block, regset, regset, regset, int));
 621 extern void free_propagate_block_info PARAMS ((struct propagate_block_info *));
 622
 623 /* In lcm.c */
 624 extern struct edge_list *pre_edge_lcm   PARAMS ((FILE *, int, sbitmap *,
 625                                                  sbitmap *, sbitmap *,
 626                                                  sbitmap *, sbitmap **,
 627                                                  sbitmap **));
 628 extern struct edge_list *pre_edge_rev_lcm PARAMS ((FILE *, int, sbitmap *,
 629                                                    sbitmap *, sbitmap *,
 630                                                    sbitmap *, sbitmap **,
 631                                                    sbitmap **));
 632 extern void compute_available           PARAMS ((sbitmap *, sbitmap *,
 633                                                  sbitmap *, sbitmap *));
 634 extern int optimize_mode_switching      PARAMS ((FILE *));
 635
 636 /* In emit-rtl.c.  */
 637 extern rtx emit_block_insn_after        PARAMS ((rtx, rtx, basic_block));
 638 extern rtx emit_block_insn_before       PARAMS ((rtx, rtx, basic_block));
 639
 640 /* In predict.c */
 641 extern void estimate_probability        PARAMS ((struct loops *));
 642 extern void note_prediction_to_br_prob  PARAMS ((void));
 643 extern void expected_value_to_br_prob   PARAMS ((void));
 644 extern void note_prediction_to_br_prob  PARAMS ((void));
 645 extern bool maybe_hot_bb_p              PARAMS ((basic_block));
 646 extern bool probably_cold_bb_p          PARAMS ((basic_block));
 647 extern bool probably_never_executed_bb_p PARAMS ((basic_block));
 648
 649 /* In flow.c */
 650 extern void init_flow                   PARAMS ((void));
 651 extern void reorder_basic_blocks        PARAMS ((void));
 652 extern void dump_bb                     PARAMS ((basic_block, FILE *));
 653 extern void debug_bb                    PARAMS ((basic_block));
 654 extern void debug_bb_n                  PARAMS ((int));
 655 extern void dump_regset                 PARAMS ((regset, FILE *));
 656 extern void debug_regset                PARAMS ((regset));
 657 extern void allocate_reg_life_data      PARAMS ((void));
 658 extern void allocate_bb_life_data       PARAMS ((void));
 659 extern void expunge_block               PARAMS ((basic_block));
 660 extern void link_block                  PARAMS ((basic_block, basic_block));
 661 extern void unlink_block                PARAMS ((basic_block));
 662 extern void expunge_block_nocompact     PARAMS ((basic_block));
 663 extern basic_block alloc_block          PARAMS ((void));
 664 extern void find_unreachable_blocks     PARAMS ((void));
 665 extern int delete_noop_moves            PARAMS ((rtx));
 666 extern basic_block redirect_edge_and_branch_force PARAMS ((edge, basic_block));
 667 extern basic_block force_nonfallthru    PARAMS ((edge));
 668 extern bool redirect_edge_and_branch    PARAMS ((edge, basic_block));
 669 extern rtx block_label                  PARAMS ((basic_block));
 670 extern bool forwarder_block_p           PARAMS ((basic_block));
 671 extern bool purge_all_dead_edges        PARAMS ((int));
 672 extern bool purge_dead_edges            PARAMS ((basic_block));
 673 extern void find_sub_basic_blocks       PARAMS ((basic_block));
 674 extern void find_many_sub_basic_blocks  PARAMS ((sbitmap));
 675 extern bool can_fallthru                PARAMS ((basic_block, basic_block));
 676 extern void flow_nodes_print            PARAMS ((const char *, const sbitmap,
 677                                                  FILE *));
 678 extern void flow_edge_list_print        PARAMS ((const char *, const edge *,
 679                                                  int, FILE *));
 680 extern void alloc_aux_for_block         PARAMS ((basic_block, int));
 681 extern void alloc_aux_for_blocks        PARAMS ((int));
 682 extern void clear_aux_for_blocks        PARAMS ((void));
 683 extern void free_aux_for_blocks         PARAMS ((void));
 684 extern void alloc_aux_for_edge          PARAMS ((edge, int));
 685 extern void alloc_aux_for_edges         PARAMS ((int));
 686 extern void clear_aux_for_edges         PARAMS ((void));
 687 extern void free_aux_for_edges          PARAMS ((void));
 688
 689 /* This function is always defined so it can be called from the
 690    debugger, and it is declared extern so we don't get warnings about
 691    it being unused.  */
 692 extern void verify_flow_info            PARAMS ((void));
 693 extern int flow_loop_outside_edge_p     PARAMS ((const struct loop *, edge));
 694
 695 typedef struct conflict_graph_def *conflict_graph;
 696
 697 /* Callback function when enumerating conflicts.  The arguments are
 698    the smaller and larger regno in the conflict.  Returns zero if
 699    enumeration is to continue, non-zero to halt enumeration.  */
 700 typedef int (*conflict_graph_enum_fn) PARAMS ((int, int, void *));
 701
 702
 703 /* Prototypes of operations on conflict graphs.  */
 704
 705 extern conflict_graph conflict_graph_new
 706                                         PARAMS ((int));
 707 extern void conflict_graph_delete       PARAMS ((conflict_graph));
 708 extern int conflict_graph_add           PARAMS ((conflict_graph,
 709                                                  int, int));
 710 extern int conflict_graph_conflict_p    PARAMS ((conflict_graph,
 711                                                  int, int));
 712 extern void conflict_graph_enum         PARAMS ((conflict_graph, int,
 713                                                  conflict_graph_enum_fn,
 714                                                  void *));
 715 extern void conflict_graph_merge_regs   PARAMS ((conflict_graph, int,
 716                                                  int));
 717 extern void conflict_graph_print        PARAMS ((conflict_graph, FILE*));
 718 extern conflict_graph conflict_graph_compute
 719                                         PARAMS ((regset,
 720                                                  partition));
 721 extern bool mark_dfs_back_edges         PARAMS ((void));
 722 extern void set_edge_can_fallthru_flag  PARAMS ((void));
 723 extern void update_br_prob_note         PARAMS ((basic_block));
 724 extern void fixup_abnormal_edges        PARAMS ((void));
 725
 726 /* In dominance.c */
 727
 728 enum cdi_direction
 729 {
 730   CDI_DOMINATORS,
 731   CDI_POST_DOMINATORS
 732 };
 733
 734 extern void calculate_dominance_info    PARAMS ((int *, sbitmap *,
 735                                                  enum cdi_direction));
 736
 737 #endif /* GCC_BASIC_BLOCK_H */