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
 145 #define EDGE_COMPLEX    (EDGE_ABNORMAL | EDGE_ABNORMAL_CALL | EDGE_EH)
 146
 147
 148 /* A basic block is a sequence of instructions with only entry and
 149    only one exit.  If any one of the instructions are executed, they
 150    will all be executed, and in sequence from first to last.
 151
 152    There may be COND_EXEC instructions in the basic block.  The
 153    COND_EXEC *instructions* will be executed -- but if the condition
 154    is false the conditionally executed *expressions* will of course
 155    not be executed.  We don't consider the conditionally executed
 156    expression (which might have side-effects) to be in a separate
 157    basic block because the program counter will always be at the same
 158    location after the COND_EXEC instruction, regardless of whether the
 159    condition is true or not.
 160
 161    Basic blocks need not start with a label nor end with a jump insn.
 162    For example, a previous basic block may just "conditionally fall"
 163    into the succeeding basic block, and the last basic block need not
 164    end with a jump insn.  Block 0 is a descendant of the entry block.
 165
 166    A basic block beginning with two labels cannot have notes between
 167    the labels.
 168
 169    Data for jump tables are stored in jump_insns that occur in no
 170    basic block even though these insns can follow or precede insns in
 171    basic blocks.  */
 172
 173 /* Basic block information indexed by block number.  */
 174 typedef struct basic_block_def {
 175   /* The first and last insns of the block.  */
 176   rtx head, end;
 177
 178   /* The first and last trees of the block.  */
 179   tree head_tree;
 180   tree end_tree;
 181
 182   /* The edges into and out of the block.  */
 183   edge pred, succ;
 184
 185   /* Liveness info.  */
 186
 187   /* The registers that are modified within this in block.  */
 188   regset local_set;
 189   /* The registers that are conditionally modified within this block.
 190      In other words, registers that are set only as part of a
 191      COND_EXEC.  */
 192   regset cond_local_set;
 193   /* The registers that are live on entry to this block.
 194
 195      Note that in SSA form, global_live_at_start does not reflect the
 196      use of regs in phi functions, since the liveness of these regs
 197      may depend on which edge was taken into the block.  */
 198   regset global_live_at_start;
 199   /* The registers that are live on exit from this block.  */
 200   regset global_live_at_end;
 201
 202   /* Auxiliary info specific to a pass.  */
 203   void *aux;
 204
 205   /* The index of this block.  */
 206   int index;
 207
 208   /* The loop depth of this block.  */
 209   int loop_depth;
 210
 211   /* Expected number of executions: calculated in profile.c.  */
 212   gcov_type count;
 213
 214   /* Expected frequency.  Normalized to be in range 0 to BB_FREQ_MAX.  */
 215   int frequency;
 216
 217   /* Various flags.  See BB_* below.  */
 218   int flags;
 219 } *basic_block;
 220
 221 #define BB_FREQ_MAX 10000
 222
 223 /* Masks for basic_block.flags.  */
 224 #define BB_REACHABLE            1
 225
 226 /* Number of basic blocks in the current function.  */
 227
 228 extern int n_basic_blocks;
 229
 230 /* Number of edges in the current function.  */
 231
 232 extern int n_edges;
 233
 234 /* Index by basic block number, get basic block struct info.  */
 235
 236 extern varray_type basic_block_info;
 237
 238 #define BASIC_BLOCK(N)  (VARRAY_BB (basic_block_info, (N)))
 239
 240 /* What registers are live at the setjmp call.  */
 241
 242 extern regset regs_live_at_setjmp;
 243
 244 /* Special labels found during CFG build.  */
 245
 246 extern rtx label_value_list, tail_recursion_label_list;
 247
 248 extern struct obstack flow_obstack;
 249
 250 /* Indexed by n, gives number of basic block that  (REG n) is used in.
 251    If the value is REG_BLOCK_GLOBAL (-2),
 252    it means (REG n) is used in more than one basic block.
 253    REG_BLOCK_UNKNOWN (-1) means it hasn't been seen yet so we don't know.
 254    This information remains valid for the rest of the compilation
 255    of the current function; it is used to control register allocation.  */
 256
 257 #define REG_BLOCK_UNKNOWN -1
 258 #define REG_BLOCK_GLOBAL -2
 259
 260 #define REG_BASIC_BLOCK(N) (VARRAY_REG (reg_n_info, N)->basic_block)
 261 \f
 262 /* Stuff for recording basic block info.  */
 263
 264 #define BLOCK_HEAD(B)      (BASIC_BLOCK (B)->head)
 265 #define BLOCK_END(B)       (BASIC_BLOCK (B)->end)
 266
 267 #define BLOCK_HEAD_TREE(B) (BASIC_BLOCK (B)->head_tree)
 268 #define BLOCK_END_TREE(B) (BASIC_BLOCK (B)->end_tree)
 269
 270 /* Special block numbers [markers] for entry and exit.  */
 271 #define ENTRY_BLOCK (-1)
 272 #define EXIT_BLOCK (-2)
 273
 274 /* Special block number not valid for any block.  */
 275 #define INVALID_BLOCK (-3)
 276
 277 /* Similarly, block pointers for the edge list.  */
 278 extern struct basic_block_def entry_exit_blocks[2];
 279 #define ENTRY_BLOCK_PTR (&entry_exit_blocks[0])
 280 #define EXIT_BLOCK_PTR  (&entry_exit_blocks[1])
 281
 282 extern varray_type basic_block_for_insn;
 283 #define BLOCK_FOR_INSN(INSN)  VARRAY_BB (basic_block_for_insn, INSN_UID (INSN))
 284 #define BLOCK_NUM(INSN)       (BLOCK_FOR_INSN (INSN)->index + 0)
 285
 286 extern void compute_bb_for_insn         PARAMS ((int));
 287 extern void free_bb_for_insn            PARAMS ((void));
 288 extern void update_bb_for_insn          PARAMS ((basic_block));
 289 extern void set_block_for_insn          PARAMS ((rtx, basic_block));
 290
 291 extern void free_basic_block_vars       PARAMS ((int));
 292
 293 extern edge split_block                 PARAMS ((basic_block, rtx));
 294 extern basic_block split_edge           PARAMS ((edge));
 295 extern void insert_insn_on_edge         PARAMS ((rtx, edge));
 296 extern void commit_edge_insertions      PARAMS ((void));
 297 extern void remove_fake_edges           PARAMS ((void));
 298 extern void add_noreturn_fake_exit_edges        PARAMS ((void));
 299 extern void connect_infinite_loops_to_exit      PARAMS ((void));
 300 extern int flow_call_edges_add          PARAMS ((sbitmap));
 301 extern edge cached_make_edge            PARAMS ((sbitmap *, basic_block,
 302                                                  basic_block, int));
 303 extern edge make_edge                   PARAMS ((basic_block,
 304                                                  basic_block, int));
 305 extern edge make_single_succ_edge       PARAMS ((basic_block,
 306                                                  basic_block, int));
 307 extern void remove_edge                 PARAMS ((edge));
 308 extern void redirect_edge_succ          PARAMS ((edge, basic_block));
 309 extern edge redirect_edge_succ_nodup    PARAMS ((edge, basic_block));
 310 extern void redirect_edge_pred          PARAMS ((edge, basic_block));
 311 extern basic_block create_basic_block_structure PARAMS ((int, rtx, rtx, rtx));
 312 extern basic_block create_basic_block   PARAMS ((int, rtx, rtx));
 313 extern int flow_delete_block            PARAMS ((basic_block));
 314 extern int flow_delete_block_noexpunge  PARAMS ((basic_block));
 315 extern void merge_blocks_nomove         PARAMS ((basic_block, basic_block));
 316 extern void tidy_fallthru_edge          PARAMS ((edge, basic_block,
 317                                                  basic_block));
 318 extern void tidy_fallthru_edges         PARAMS ((void));
 319 extern void flow_reverse_top_sort_order_compute PARAMS ((int *));
 320 extern int flow_depth_first_order_compute       PARAMS ((int *, int *));
 321 extern void flow_preorder_transversal_compute   PARAMS ((int *));
 322 extern void dump_edge_info              PARAMS ((FILE *, edge, int));
 323 extern void clear_edges                 PARAMS ((void));
 324 extern void mark_critical_edges         PARAMS ((void));
 325 extern rtx first_insn_after_basic_block_note    PARAMS ((basic_block));
 326
 327 /* Structure to hold information for each natural loop.  */
 328 struct loop
 329 {
 330   /* Index into loops array.  */
 331   int num;
 332
 333   /* Basic block of loop header.  */
 334   basic_block header;
 335
 336   /* Basic block of loop latch.  */
 337   basic_block latch;
 338
 339   /* Basic block of loop pre-header or NULL if it does not exist.  */
 340   basic_block pre_header;
 341
 342   /* Array of edges along the pre-header extended basic block trace.
 343      The source of the first edge is the root node of pre-header
 344      extended basic block, if it exists.  */
 345   edge *pre_header_edges;
 346
 347   /* Number of edges along the pre_header extended basic block trace.  */
 348   int num_pre_header_edges;
 349
 350   /* The first block in the loop.  This is not necessarily the same as
 351      the loop header.  */
 352   basic_block first;
 353
 354   /* The last block in the loop.  This is not necessarily the same as
 355      the loop latch.  */
 356   basic_block last;
 357
 358   /* Bitmap of blocks contained within the loop.  */
 359   sbitmap nodes;
 360
 361   /* Number of blocks contained within the loop.  */
 362   int num_nodes;
 363
 364   /* Array of edges that enter the loop.  */
 365   edge *entry_edges;
 366
 367   /* Number of edges that enter the loop.  */
 368   int num_entries;
 369
 370   /* Array of edges that exit the loop.  */
 371   edge *exit_edges;
 372
 373   /* Number of edges that exit the loop.  */
 374   int num_exits;
 375
 376   /* Bitmap of blocks that dominate all exits of the loop.  */
 377   sbitmap exits_doms;
 378
 379   /* The loop nesting depth.  */
 380   int depth;
 381
 382   /* The height of the loop (enclosed loop levels) within the loop
 383      hierarchy tree.  */
 384   int level;
 385
 386   /* The outer (parent) loop or NULL if outermost loop.  */
 387   struct loop *outer;
 388
 389   /* The first inner (child) loop or NULL if innermost loop.  */
 390   struct loop *inner;
 391
 392   /* Link to the next (sibling) loop.  */
 393   struct loop *next;
 394
 395   /* Non-zero if the loop shares a header with another loop.  */
 396   int shared;
 397
 398   /* Non-zero if the loop is invalid (e.g., contains setjmp.).  */
 399   int invalid;
 400
 401   /* Auxiliary info specific to a pass.  */
 402   void *aux;
 403
 404   /* The following are currently used by loop.c but they are likely to
 405      disappear as loop.c is converted to use the CFG.  */
 406
 407   /* Non-zero if the loop has a NOTE_INSN_LOOP_VTOP.  */
 408   rtx vtop;
 409
 410   /* Non-zero if the loop has a NOTE_INSN_LOOP_CONT.
 411      A continue statement will generate a branch to NEXT_INSN (cont).  */
 412   rtx cont;
 413
 414   /* The dominator of cont.  */
 415   rtx cont_dominator;
 416
 417   /* The NOTE_INSN_LOOP_BEG.  */
 418   rtx start;
 419
 420   /* The NOTE_INSN_LOOP_END.  */
 421   rtx end;
 422
 423   /* For a rotated loop that is entered near the bottom,
 424      this is the label at the top.  Otherwise it is zero.  */
 425   rtx top;
 426
 427   /* Place in the loop where control enters.  */
 428   rtx scan_start;
 429
 430   /* The position where to sink insns out of the loop.  */
 431   rtx sink;
 432
 433   /* List of all LABEL_REFs which refer to code labels outside the
 434      loop.  Used by routines that need to know all loop exits, such as
 435      final_biv_value and final_giv_value.
 436
 437      This does not include loop exits due to return instructions.
 438      This is because all bivs and givs are pseudos, and hence must be
 439      dead after a return, so the presense of a return does not affect
 440      any of the optimizations that use this info.  It is simpler to
 441      just not include return instructions on this list.  */
 442   rtx exit_labels;
 443
 444   /* The number of LABEL_REFs on exit_labels for this loop and all
 445      loops nested inside it.  */
 446   int exit_count;
 447 };
 448
 449
 450 /* Structure to hold CFG information about natural loops within a function.  */
 451 struct loops
 452 {
 453   /* Number of natural loops in the function.  */
 454   int num;
 455
 456   /* Maxium nested loop level in the function.  */
 457   int levels;
 458
 459   /* Array of natural loop descriptors (scanning this array in reverse order
 460      will find the inner loops before their enclosing outer loops).  */
 461   struct loop *array;
 462
 463   /* Pointer to root of loop heirachy tree.  */
 464   struct loop *tree_root;
 465
 466   /* Information derived from the CFG.  */
 467   struct cfg
 468   {
 469     /* The bitmap vector of dominators or NULL if not computed.  */
 470     sbitmap *dom;
 471
 472     /* The ordering of the basic blocks in a depth first search.  */
 473     int *dfs_order;
 474
 475     /* The reverse completion ordering of the basic blocks found in a
 476        depth first search.  */
 477     int *rc_order;
 478   } cfg;
 479
 480   /* Headers shared by multiple loops that should be merged.  */
 481   sbitmap shared_headers;
 482 };
 483
 484 extern int flow_loops_find PARAMS ((struct loops *, int flags));
 485 extern int flow_loops_update PARAMS ((struct loops *, int flags));
 486 extern void flow_loops_free PARAMS ((struct loops *));
 487 extern void flow_loops_dump PARAMS ((const struct loops *, FILE *,
 488                                      void (*)(const struct loop *,
 489                                               FILE *, int), int));
 490 extern void flow_loop_dump PARAMS ((const struct loop *, FILE *,
 491                                     void (*)(const struct loop *,
 492                                              FILE *, int), int));
 493 extern int flow_loop_scan PARAMS ((struct loops *, struct loop *, int));
 494
 495 /* This structure maintains an edge list vector.  */
 496 struct edge_list
 497 {
 498   int num_blocks;
 499   int num_edges;
 500   edge *index_to_edge;
 501 };
 502
 503 /* This is the value which indicates no edge is present.  */
 504 #define EDGE_INDEX_NO_EDGE      -1
 505
 506 /* EDGE_INDEX returns an integer index for an edge, or EDGE_INDEX_NO_EDGE
 507    if there is no edge between the 2 basic blocks.  */
 508 #define EDGE_INDEX(el, pred, succ) (find_edge_index ((el), (pred), (succ)))
 509
 510 /* INDEX_EDGE_PRED_BB and INDEX_EDGE_SUCC_BB return a pointer to the basic
 511    block which is either the pred or succ end of the indexed edge.  */
 512 #define INDEX_EDGE_PRED_BB(el, index)   ((el)->index_to_edge[(index)]->src)
 513 #define INDEX_EDGE_SUCC_BB(el, index)   ((el)->index_to_edge[(index)]->dest)
 514
 515 /* INDEX_EDGE returns a pointer to the edge.  */
 516 #define INDEX_EDGE(el, index)           ((el)->index_to_edge[(index)])
 517
 518 /* Number of edges in the compressed edge list.  */
 519 #define NUM_EDGES(el)                   ((el)->num_edges)
 520
 521 /* BB is assumed to contain conditional jump.  Return the fallthru edge.  */
 522 #define FALLTHRU_EDGE(bb)               ((bb)->succ->flags & EDGE_FALLTHRU \
 523                                          ? (bb)->succ : (bb)->succ->succ_next)
 524
 525 /* BB is assumed to contain conditional jump.  Return the branch edge.  */
 526 #define BRANCH_EDGE(bb)                 ((bb)->succ->flags & EDGE_FALLTHRU \
 527                                          ? (bb)->succ->succ_next : (bb)->succ)
 528
 529 /* Return expected execution frequency of the edge E.  */
 530 #define EDGE_FREQUENCY(e)               (((e)->src->frequency \
 531                                           * (e)->probability \
 532                                           + REG_BR_PROB_BASE / 2) \
 533                                          / REG_BR_PROB_BASE)
 534
 535 /* Return nonzero if edge is critical.  */
 536 #define EDGE_CRITICAL_P(e)              ((e)->src->succ->succ_next \
 537                                          && (e)->dest->pred->pred_next)
 538
 539 struct edge_list * create_edge_list     PARAMS ((void));
 540 void free_edge_list                     PARAMS ((struct edge_list *));
 541 void print_edge_list                    PARAMS ((FILE *, struct edge_list *));
 542 void verify_edge_list                   PARAMS ((FILE *, struct edge_list *));
 543 int find_edge_index                     PARAMS ((struct edge_list *,
 544                                                  basic_block, basic_block));
 545
 546
 547 enum update_life_extent
 548 {
 549   UPDATE_LIFE_LOCAL = 0,
 550   UPDATE_LIFE_GLOBAL = 1,
 551   UPDATE_LIFE_GLOBAL_RM_NOTES = 2
 552 };
 553
 554 /* Flags for life_analysis and update_life_info.  */
 555
 556 #define PROP_DEATH_NOTES        1       /* Create DEAD and UNUSED notes.  */
 557 #define PROP_LOG_LINKS          2       /* Create LOG_LINKS.  */
 558 #define PROP_REG_INFO           4       /* Update regs_ever_live et al.  */
 559 #define PROP_KILL_DEAD_CODE     8       /* Remove dead code.  */
 560 #define PROP_SCAN_DEAD_CODE     16      /* Scan for dead code.  */
 561 #define PROP_ALLOW_CFG_CHANGES  32      /* Allow the CFG to be changed
 562                                            by dead code removal.  */
 563 #define PROP_AUTOINC            64      /* Create autoinc mem references.  */
 564 #define PROP_EQUAL_NOTES        128     /* Take into account REG_EQUAL notes.  */
 565 #define PROP_FINAL              127     /* All of the above.  */
 566
 567 #define CLEANUP_EXPENSIVE       1       /* Do relativly expensive optimizations
 568                                            except for edge forwarding */
 569 #define CLEANUP_CROSSJUMP       2       /* Do crossjumping.  */
 570 #define CLEANUP_POST_REGSTACK   4       /* We run after reg-stack and need
 571                                            to care REG_DEAD notes.  */
 572 #define CLEANUP_PRE_SIBCALL     8       /* Do not get confused by code hidden
 573                                            inside call_placeholders..  */
 574 #define CLEANUP_PRE_LOOP        16      /* Take care to preserve syntactic loop
 575                                            notes.  */
 576 #define CLEANUP_UPDATE_LIFE     32      /* Keep life information up to date.  */
 577 #define CLEANUP_THREADING       64      /* Do jump threading.  */
 578 /* Flags for loop discovery.  */
 579
 580 #define LOOP_TREE               1       /* Build loop hierarchy tree.  */
 581 #define LOOP_PRE_HEADER         2       /* Analyse loop pre-header.  */
 582 #define LOOP_ENTRY_EDGES        4       /* Find entry edges.  */
 583 #define LOOP_EXIT_EDGES         8       /* Find exit edges.  */
 584 #define LOOP_EDGES              (LOOP_ENTRY_EDGES | LOOP_EXIT_EDGES)
 585 #define LOOP_EXITS_DOMS        16       /* Find nodes that dom. all exits.  */
 586 #define LOOP_ALL               31       /* All of the above  */
 587
 588 extern void life_analysis       PARAMS ((rtx, FILE *, int));
 589 extern void update_life_info    PARAMS ((sbitmap, enum update_life_extent,
 590                                          int));
 591 extern int count_or_remove_death_notes  PARAMS ((sbitmap, int));
 592 extern int propagate_block      PARAMS ((basic_block, regset, regset, regset,
 593                                          int));
 594
 595 struct propagate_block_info;
 596 extern rtx propagate_one_insn   PARAMS ((struct propagate_block_info *, rtx));
 597 extern struct propagate_block_info *init_propagate_block_info
 598   PARAMS ((basic_block, regset, regset, regset, int));
 599 extern void free_propagate_block_info PARAMS ((struct propagate_block_info *));
 600
 601 /* In lcm.c */
 602 extern struct edge_list *pre_edge_lcm   PARAMS ((FILE *, int, sbitmap *,
 603                                                  sbitmap *, sbitmap *,
 604                                                  sbitmap *, sbitmap **,
 605                                                  sbitmap **));
 606 extern struct edge_list *pre_edge_rev_lcm PARAMS ((FILE *, int, sbitmap *,
 607                                                    sbitmap *, sbitmap *,
 608                                                    sbitmap *, sbitmap **,
 609                                                    sbitmap **));
 610 extern void compute_available           PARAMS ((sbitmap *, sbitmap *,
 611                                                  sbitmap *, sbitmap *));
 612 extern int optimize_mode_switching      PARAMS ((FILE *));
 613
 614 /* In emit-rtl.c.  */
 615 extern rtx emit_block_insn_after        PARAMS ((rtx, rtx, basic_block));
 616 extern rtx emit_block_insn_before       PARAMS ((rtx, rtx, basic_block));
 617
 618 /* In predict.c */
 619 extern void estimate_probability        PARAMS ((struct loops *));
 620 extern void expected_value_to_br_prob   PARAMS ((void));
 621
 622 /* In flow.c */
 623 extern void init_flow                   PARAMS ((void));
 624 extern void reorder_basic_blocks        PARAMS ((void));
 625 extern void dump_bb                     PARAMS ((basic_block, FILE *));
 626 extern void debug_bb                    PARAMS ((basic_block));
 627 extern void debug_bb_n                  PARAMS ((int));
 628 extern void dump_regset                 PARAMS ((regset, FILE *));
 629 extern void debug_regset                PARAMS ((regset));
 630 extern void allocate_reg_life_data      PARAMS ((void));
 631 extern void allocate_bb_life_data       PARAMS ((void));
 632 extern void expunge_block               PARAMS ((basic_block));
 633 extern void expunge_block_nocompact     PARAMS ((basic_block));
 634 extern basic_block alloc_block          PARAMS ((void));
 635 extern void find_unreachable_blocks     PARAMS ((void));
 636 extern void delete_noop_moves           PARAMS ((rtx));
 637 extern basic_block redirect_edge_and_branch_force PARAMS ((edge, basic_block));
 638 extern basic_block force_nonfallthru    PARAMS ((edge));
 639 extern bool redirect_edge_and_branch    PARAMS ((edge, basic_block));
 640 extern rtx block_label                  PARAMS ((basic_block));
 641 extern bool forwarder_block_p           PARAMS ((basic_block));
 642 extern bool purge_all_dead_edges        PARAMS ((int));
 643 extern bool purge_dead_edges            PARAMS ((basic_block));
 644 extern void find_sub_basic_blocks       PARAMS ((basic_block));
 645 extern void find_many_sub_basic_blocks  PARAMS ((sbitmap));
 646 extern bool can_fallthru                PARAMS ((basic_block, basic_block));
 647 extern void flow_nodes_print            PARAMS ((const char *, const sbitmap,
 648                                                  FILE *));
 649 extern void flow_edge_list_print        PARAMS ((const char *, const edge *,
 650                                                  int, FILE *));
 651 extern void alloc_aux_for_block         PARAMS ((basic_block, int));
 652 extern void alloc_aux_for_blocks        PARAMS ((int));
 653 extern void clear_aux_for_blocks        PARAMS ((void));
 654 extern void free_aux_for_blocks         PARAMS ((void));
 655 extern void alloc_aux_for_edge          PARAMS ((edge, int));
 656 extern void alloc_aux_for_edges         PARAMS ((int));
 657 extern void clear_aux_for_edges         PARAMS ((void));
 658 extern void free_aux_for_edges          PARAMS ((void));
 659
 660 /* This function is always defined so it can be called from the
 661    debugger, and it is declared extern so we don't get warnings about
 662    it being unused.  */
 663 extern void verify_flow_info            PARAMS ((void));
 664 extern int flow_loop_outside_edge_p     PARAMS ((const struct loop *, edge));
 665
 666 typedef struct conflict_graph_def *conflict_graph;
 667
 668 /* Callback function when enumerating conflicts.  The arguments are
 669    the smaller and larger regno in the conflict.  Returns zero if
 670    enumeration is to continue, non-zero to halt enumeration.  */
 671 typedef int (*conflict_graph_enum_fn) PARAMS ((int, int, void *));
 672
 673
 674 /* Prototypes of operations on conflict graphs.  */
 675
 676 extern conflict_graph conflict_graph_new
 677                                         PARAMS ((int));
 678 extern void conflict_graph_delete       PARAMS ((conflict_graph));
 679 extern int conflict_graph_add           PARAMS ((conflict_graph,
 680                                                  int, int));
 681 extern int conflict_graph_conflict_p    PARAMS ((conflict_graph,
 682                                                  int, int));
 683 extern void conflict_graph_enum         PARAMS ((conflict_graph, int,
 684                                                  conflict_graph_enum_fn,
 685                                                  void *));
 686 extern void conflict_graph_merge_regs   PARAMS ((conflict_graph, int,
 687                                                  int));
 688 extern void conflict_graph_print        PARAMS ((conflict_graph, FILE*));
 689 extern conflict_graph conflict_graph_compute
 690                                         PARAMS ((regset,
 691                                                  partition));
 692 extern bool mark_dfs_back_edges         PARAMS ((void));
 693 extern void update_br_prob_note         PARAMS ((basic_block));
 694 extern void fixup_abnormal_edges        PARAMS ((void));
 695
 696 /* In dominance.c */
 697
 698 enum cdi_direction
 699 {
 700   CDI_DOMINATORS,
 701   CDI_POST_DOMINATORS
 702 };
 703
 704 extern void calculate_dominance_info    PARAMS ((int *, sbitmap *,
 705                                                  enum cdi_direction));
 706
 707 #endif /* GCC_BASIC_BLOCK_H */