gcc/basic-block.h

   1 /* Define control flow data structures for the CFG.
   2    Copyright (C) 1987-2016 Free Software Foundation, Inc.
   3
   4 This file is part of GCC.
   5
   6 GCC is free software; you can redistribute it and/or modify it under
   7 the terms of the GNU General Public License as published by the Free
   8 Software Foundation; either version 3, or (at your option) any later
   9 version.
  10
  11 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
  12 WARRANTY; without even the implied warranty of MERCHANTABILITY or
  13 FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  14 for more details.
  15
  16 You should have received a copy of the GNU General Public License
  17 along with GCC; see the file COPYING3.  If not see
  18 <http://www.gnu.org/licenses/>.  */
  19
  20 #ifndef GCC_BASIC_BLOCK_H
  21 #define GCC_BASIC_BLOCK_H
  22
  23
  24 /* Use gcov_type to hold basic block counters.  Should be at least
  25    64bit.  Although a counter cannot be negative, we use a signed
  26    type, because erroneous negative counts can be generated when the
  27    flow graph is manipulated by various optimizations.  A signed type
  28    makes those easy to detect.  */
  29
  30 /* Control flow edge information.  */
  31 struct GTY((user)) edge_def {
  32   /* The two blocks at the ends of the edge.  */
  33   basic_block src;
  34   basic_block dest;
  35
  36   /* Instructions queued on the edge.  */
  37   union edge_def_insns {
  38     gimple_seq g;
  39     rtx_insn *r;
  40   } insns;
  41
  42   /* Auxiliary info specific to a pass.  */
  43   PTR aux;
  44
  45   /* Location of any goto implicit in the edge.  */
  46   location_t goto_locus;
  47
  48   /* The index number corresponding to this edge in the edge vector
  49      dest->preds.  */
  50   unsigned int dest_idx;
  51
  52   int flags;                    /* see cfg-flags.def */
  53   int probability;              /* biased by REG_BR_PROB_BASE */
  54   gcov_type count;              /* Expected number of executions calculated
  55                                    in profile.c  */
  56 };
  57
  58 /* Masks for edge.flags.  */
  59 #define DEF_EDGE_FLAG(NAME,IDX) EDGE_##NAME = 1 << IDX ,
  60 enum cfg_edge_flags {
  61 #include "cfg-flags.def"
  62   LAST_CFG_EDGE_FLAG            /* this is only used for EDGE_ALL_FLAGS */
  63 };
  64 #undef DEF_EDGE_FLAG
  65
  66 /* Bit mask for all edge flags.  */
  67 #define EDGE_ALL_FLAGS          ((LAST_CFG_EDGE_FLAG - 1) * 2 - 1)
  68
  69 /* The following four flags all indicate something special about an edge.
  70    Test the edge flags on EDGE_COMPLEX to detect all forms of "strange"
  71    control flow transfers.  */
  72 #define EDGE_COMPLEX \
  73   (EDGE_ABNORMAL | EDGE_ABNORMAL_CALL | EDGE_EH | EDGE_PRESERVE)
  74
  75 struct GTY(()) rtl_bb_info {
  76   /* The first insn of the block is embedded into bb->il.x.  */
  77   /* The last insn of the block.  */
  78   rtx_insn *end_;
  79
  80   /* In CFGlayout mode points to insn notes/jumptables to be placed just before
  81      and after the block.   */
  82   rtx_insn *header_;
  83   rtx_insn *footer_;
  84 };
  85
  86 struct GTY(()) gimple_bb_info {
  87   /* Sequence of statements in this block.  */
  88   gimple_seq seq;
  89
  90   /* PHI nodes for this block.  */
  91   gimple_seq phi_nodes;
  92 };
  93
  94 /* A basic block is a sequence of instructions with only one entry and
  95    only one exit.  If any one of the instructions are executed, they
  96    will all be executed, and in sequence from first to last.
  97
  98    There may be COND_EXEC instructions in the basic block.  The
  99    COND_EXEC *instructions* will be executed -- but if the condition
 100    is false the conditionally executed *expressions* will of course
 101    not be executed.  We don't consider the conditionally executed
 102    expression (which might have side-effects) to be in a separate
 103    basic block because the program counter will always be at the same
 104    location after the COND_EXEC instruction, regardless of whether the
 105    condition is true or not.
 106
 107    Basic blocks need not start with a label nor end with a jump insn.
 108    For example, a previous basic block may just "conditionally fall"
 109    into the succeeding basic block, and the last basic block need not
 110    end with a jump insn.  Block 0 is a descendant of the entry block.
 111
 112    A basic block beginning with two labels cannot have notes between
 113    the labels.
 114
 115    Data for jump tables are stored in jump_insns that occur in no
 116    basic block even though these insns can follow or precede insns in
 117    basic blocks.  */
 118
 119 /* Basic block information indexed by block number.  */
 120 struct GTY((chain_next ("%h.next_bb"), chain_prev ("%h.prev_bb"))) basic_block_def {
 121   /* The edges into and out of the block.  */
 122   vec<edge, va_gc> *preds;
 123   vec<edge, va_gc> *succs;
 124
 125   /* Auxiliary info specific to a pass.  */
 126   PTR GTY ((skip (""))) aux;
 127
 128   /* Innermost loop containing the block.  */
 129   struct loop *loop_father;
 130
 131   /* The dominance and postdominance information node.  */
 132   struct et_node * GTY ((skip (""))) dom[2];
 133
 134   /* Previous and next blocks in the chain.  */
 135   basic_block prev_bb;
 136   basic_block next_bb;
 137
 138   union basic_block_il_dependent {
 139       struct gimple_bb_info GTY ((tag ("0"))) gimple;
 140       struct {
 141         rtx_insn *head_;
 142         struct rtl_bb_info * rtl;
 143       } GTY ((tag ("1"))) x;
 144     } GTY ((desc ("((%1.flags & BB_RTL) != 0)"))) il;
 145
 146   /* Various flags.  See cfg-flags.def.  */
 147   int flags;
 148
 149   /* The index of this block.  */
 150   int index;
 151
 152   /* Expected number of executions: calculated in profile.c.  */
 153   gcov_type count;
 154
 155   /* Expected frequency.  Normalized to be in range 0 to BB_FREQ_MAX.  */
 156   int frequency;
 157
 158   /* The discriminator for this block.  The discriminator distinguishes
 159      among several basic blocks that share a common locus, allowing for
 160      more accurate sample-based profiling.  */
 161   int discriminator;
 162 };
 163
 164 /* This ensures that struct gimple_bb_info is smaller than
 165    struct rtl_bb_info, so that inlining the former into basic_block_def
 166    is the better choice.  */
 167 typedef int __assert_gimple_bb_smaller_rtl_bb
 168               [(int) sizeof (struct rtl_bb_info)
 169                - (int) sizeof (struct gimple_bb_info)];
 170
 171
 172 #define BB_FREQ_MAX 10000
 173
 174 /* Masks for basic_block.flags.  */
 175 #define DEF_BASIC_BLOCK_FLAG(NAME,IDX) BB_##NAME = 1 << IDX ,
 176 enum cfg_bb_flags
 177 {
 178 #include "cfg-flags.def"
 179   LAST_CFG_BB_FLAG              /* this is only used for BB_ALL_FLAGS */
 180 };
 181 #undef DEF_BASIC_BLOCK_FLAG
 182
 183 /* Bit mask for all basic block flags.  */
 184 #define BB_ALL_FLAGS            ((LAST_CFG_BB_FLAG - 1) * 2 - 1)
 185
 186 /* Bit mask for all basic block flags that must be preserved.  These are
 187    the bit masks that are *not* cleared by clear_bb_flags.  */
 188 #define BB_FLAGS_TO_PRESERVE                                    \
 189   (BB_DISABLE_SCHEDULE | BB_RTL | BB_NON_LOCAL_GOTO_TARGET      \
 190    | BB_HOT_PARTITION | BB_COLD_PARTITION)
 191
 192 /* Dummy bitmask for convenience in the hot/cold partitioning code.  */
 193 #define BB_UNPARTITIONED        0
 194
 195 /* Partitions, to be used when partitioning hot and cold basic blocks into
 196    separate sections.  */
 197 #define BB_PARTITION(bb) ((bb)->flags & (BB_HOT_PARTITION|BB_COLD_PARTITION))
 198 #define BB_SET_PARTITION(bb, part) do {                                 \
 199   basic_block bb_ = (bb);                                               \
 200   bb_->flags = ((bb_->flags & ~(BB_HOT_PARTITION|BB_COLD_PARTITION))    \
 201                 | (part));                                              \
 202 } while (0)
 203
 204 #define BB_COPY_PARTITION(dstbb, srcbb) \
 205   BB_SET_PARTITION (dstbb, BB_PARTITION (srcbb))
 206
 207 /* Defines for accessing the fields of the CFG structure for function FN.  */
 208 #define ENTRY_BLOCK_PTR_FOR_FN(FN)           ((FN)->cfg->x_entry_block_ptr)
 209 #define EXIT_BLOCK_PTR_FOR_FN(FN)            ((FN)->cfg->x_exit_block_ptr)
 210 #define basic_block_info_for_fn(FN)          ((FN)->cfg->x_basic_block_info)
 211 #define n_basic_blocks_for_fn(FN)            ((FN)->cfg->x_n_basic_blocks)
 212 #define n_edges_for_fn(FN)                   ((FN)->cfg->x_n_edges)
 213 #define last_basic_block_for_fn(FN)          ((FN)->cfg->x_last_basic_block)
 214 #define label_to_block_map_for_fn(FN)        ((FN)->cfg->x_label_to_block_map)
 215 #define profile_status_for_fn(FN)            ((FN)->cfg->x_profile_status)
 216
 217 #define BASIC_BLOCK_FOR_FN(FN,N) \
 218   ((*basic_block_info_for_fn (FN))[(N)])
 219 #define SET_BASIC_BLOCK_FOR_FN(FN,N,BB) \
 220   ((*basic_block_info_for_fn (FN))[(N)] = (BB))
 221
 222 /* For iterating over basic blocks.  */
 223 #define FOR_BB_BETWEEN(BB, FROM, TO, DIR) \
 224   for (BB = FROM; BB != TO; BB = BB->DIR)
 225
 226 #define FOR_EACH_BB_FN(BB, FN) \
 227   FOR_BB_BETWEEN (BB, (FN)->cfg->x_entry_block_ptr->next_bb, (FN)->cfg->x_exit_block_ptr, next_bb)
 228
 229 #define FOR_EACH_BB_REVERSE_FN(BB, FN) \
 230   FOR_BB_BETWEEN (BB, (FN)->cfg->x_exit_block_ptr->prev_bb, (FN)->cfg->x_entry_block_ptr, prev_bb)
 231
 232 /* For iterating over insns in basic block.  */
 233 #define FOR_BB_INSNS(BB, INSN)                  \
 234   for ((INSN) = BB_HEAD (BB);                   \
 235        (INSN) && (INSN) != NEXT_INSN (BB_END (BB));     \
 236        (INSN) = NEXT_INSN (INSN))
 237
 238 /* For iterating over insns in basic block when we might remove the
 239    current insn.  */
 240 #define FOR_BB_INSNS_SAFE(BB, INSN, CURR)                       \
 241   for ((INSN) = BB_HEAD (BB), (CURR) = (INSN) ? NEXT_INSN ((INSN)): NULL;       \
 242        (INSN) && (INSN) != NEXT_INSN (BB_END (BB));     \
 243        (INSN) = (CURR), (CURR) = (INSN) ? NEXT_INSN ((INSN)) : NULL)
 244
 245 #define FOR_BB_INSNS_REVERSE(BB, INSN)          \
 246   for ((INSN) = BB_END (BB);                    \
 247        (INSN) && (INSN) != PREV_INSN (BB_HEAD (BB));    \
 248        (INSN) = PREV_INSN (INSN))
 249
 250 #define FOR_BB_INSNS_REVERSE_SAFE(BB, INSN, CURR)       \
 251   for ((INSN) = BB_END (BB),(CURR) = (INSN) ? PREV_INSN ((INSN)) : NULL;        \
 252        (INSN) && (INSN) != PREV_INSN (BB_HEAD (BB));    \
 253        (INSN) = (CURR), (CURR) = (INSN) ? PREV_INSN ((INSN)) : NULL)
 254
 255 /* Cycles through _all_ basic blocks, even the fake ones (entry and
 256    exit block).  */
 257
 258 #define FOR_ALL_BB_FN(BB, FN) \
 259   for (BB = ENTRY_BLOCK_PTR_FOR_FN (FN); BB; BB = BB->next_bb)
 260
 261 \f
 262 /* Stuff for recording basic block info.  */
 263
 264 /* For now, these will be functions (so that they can include checked casts
 265    to rtx_insn.   Once the underlying fields are converted from rtx
 266    to rtx_insn, these can be converted back to macros.  */
 267
 268 #define BB_HEAD(B)      (B)->il.x.head_
 269 #define BB_END(B)       (B)->il.x.rtl->end_
 270 #define BB_HEADER(B)    (B)->il.x.rtl->header_
 271 #define BB_FOOTER(B)    (B)->il.x.rtl->footer_
 272
 273 /* Special block numbers [markers] for entry and exit.
 274    Neither of them is supposed to hold actual statements.  */
 275 #define ENTRY_BLOCK (0)
 276 #define EXIT_BLOCK (1)
 277
 278 /* The two blocks that are always in the cfg.  */
 279 #define NUM_FIXED_BLOCKS (2)
 280
 281 /* The base value for branch probability notes and edge probabilities.  */
 282 #define REG_BR_PROB_BASE  10000
 283
 284 /* This is the value which indicates no edge is present.  */
 285 #define EDGE_INDEX_NO_EDGE      -1
 286
 287 /* EDGE_INDEX returns an integer index for an edge, or EDGE_INDEX_NO_EDGE
 288    if there is no edge between the 2 basic blocks.  */
 289 #define EDGE_INDEX(el, pred, succ) (find_edge_index ((el), (pred), (succ)))
 290
 291 /* INDEX_EDGE_PRED_BB and INDEX_EDGE_SUCC_BB return a pointer to the basic
 292    block which is either the pred or succ end of the indexed edge.  */
 293 #define INDEX_EDGE_PRED_BB(el, index)   ((el)->index_to_edge[(index)]->src)
 294 #define INDEX_EDGE_SUCC_BB(el, index)   ((el)->index_to_edge[(index)]->dest)
 295
 296 /* INDEX_EDGE returns a pointer to the edge.  */
 297 #define INDEX_EDGE(el, index)           ((el)->index_to_edge[(index)])
 298
 299 /* Number of edges in the compressed edge list.  */
 300 #define NUM_EDGES(el)                   ((el)->num_edges)
 301
 302 /* BB is assumed to contain conditional jump.  Return the fallthru edge.  */
 303 #define FALLTHRU_EDGE(bb)               (EDGE_SUCC ((bb), 0)->flags & EDGE_FALLTHRU \
 304                                          ? EDGE_SUCC ((bb), 0) : EDGE_SUCC ((bb), 1))
 305
 306 /* BB is assumed to contain conditional jump.  Return the branch edge.  */
 307 #define BRANCH_EDGE(bb)                 (EDGE_SUCC ((bb), 0)->flags & EDGE_FALLTHRU \
 308                                          ? EDGE_SUCC ((bb), 1) : EDGE_SUCC ((bb), 0))
 309
 310 #define RDIV(X,Y) (((X) + (Y) / 2) / (Y))
 311 /* Return expected execution frequency of the edge E.  */
 312 #define EDGE_FREQUENCY(e)               RDIV ((e)->src->frequency * (e)->probability, \
 313                                               REG_BR_PROB_BASE)
 314
 315 /* Compute a scale factor (or probability) suitable for scaling of
 316    gcov_type values via apply_probability() and apply_scale().  */
 317 #define GCOV_COMPUTE_SCALE(num,den) \
 318   ((den) ? RDIV ((num) * REG_BR_PROB_BASE, (den)) : REG_BR_PROB_BASE)
 319
 320 /* Return nonzero if edge is critical.  */
 321 #define EDGE_CRITICAL_P(e)              (EDGE_COUNT ((e)->src->succs) >= 2 \
 322                                          && EDGE_COUNT ((e)->dest->preds) >= 2)
 323
 324 #define EDGE_COUNT(ev)                  vec_safe_length (ev)
 325 #define EDGE_I(ev,i)                    (*ev)[(i)]
 326 #define EDGE_PRED(bb,i)                 (*(bb)->preds)[(i)]
 327 #define EDGE_SUCC(bb,i)                 (*(bb)->succs)[(i)]
 328
 329 /* Returns true if BB has precisely one successor.  */
 330
 331 static inline bool
 332 single_succ_p (const_basic_block bb)
 333 {
 334   return EDGE_COUNT (bb->succs) == 1;
 335 }
 336
 337 /* Returns true if BB has precisely one predecessor.  */
 338
 339 static inline bool
 340 single_pred_p (const_basic_block bb)
 341 {
 342   return EDGE_COUNT (bb->preds) == 1;
 343 }
 344
 345 /* Returns the single successor edge of basic block BB.  Aborts if
 346    BB does not have exactly one successor.  */
 347
 348 static inline edge
 349 single_succ_edge (const_basic_block bb)
 350 {
 351   gcc_checking_assert (single_succ_p (bb));
 352   return EDGE_SUCC (bb, 0);
 353 }
 354
 355 /* Returns the single predecessor edge of basic block BB.  Aborts
 356    if BB does not have exactly one predecessor.  */
 357
 358 static inline edge
 359 single_pred_edge (const_basic_block bb)
 360 {
 361   gcc_checking_assert (single_pred_p (bb));
 362   return EDGE_PRED (bb, 0);
 363 }
 364
 365 /* Returns the single successor block of basic block BB.  Aborts
 366    if BB does not have exactly one successor.  */
 367
 368 static inline basic_block
 369 single_succ (const_basic_block bb)
 370 {
 371   return single_succ_edge (bb)->dest;
 372 }
 373
 374 /* Returns the single predecessor block of basic block BB.  Aborts
 375    if BB does not have exactly one predecessor.*/
 376
 377 static inline basic_block
 378 single_pred (const_basic_block bb)
 379 {
 380   return single_pred_edge (bb)->src;
 381 }
 382
 383 /* Iterator object for edges.  */
 384
 385 struct edge_iterator {
 386   unsigned index;
 387   vec<edge, va_gc> **container;
 388 };
 389
 390 static inline vec<edge, va_gc> *
 391 ei_container (edge_iterator i)
 392 {
 393   gcc_checking_assert (i.container);
 394   return *i.container;
 395 }
 396
 397 #define ei_start(iter) ei_start_1 (&(iter))
 398 #define ei_last(iter) ei_last_1 (&(iter))
 399
 400 /* Return an iterator pointing to the start of an edge vector.  */
 401 static inline edge_iterator
 402 ei_start_1 (vec<edge, va_gc> **ev)
 403 {
 404   edge_iterator i;
 405
 406   i.index = 0;
 407   i.container = ev;
 408
 409   return i;
 410 }
 411
 412 /* Return an iterator pointing to the last element of an edge
 413    vector.  */
 414 static inline edge_iterator
 415 ei_last_1 (vec<edge, va_gc> **ev)
 416 {
 417   edge_iterator i;
 418
 419   i.index = EDGE_COUNT (*ev) - 1;
 420   i.container = ev;
 421
 422   return i;
 423 }
 424
 425 /* Is the iterator `i' at the end of the sequence?  */
 426 static inline bool
 427 ei_end_p (edge_iterator i)
 428 {
 429   return (i.index == EDGE_COUNT (ei_container (i)));
 430 }
 431
 432 /* Is the iterator `i' at one position before the end of the
 433    sequence?  */
 434 static inline bool
 435 ei_one_before_end_p (edge_iterator i)
 436 {
 437   return (i.index + 1 == EDGE_COUNT (ei_container (i)));
 438 }
 439
 440 /* Advance the iterator to the next element.  */
 441 static inline void
 442 ei_next (edge_iterator *i)
 443 {
 444   gcc_checking_assert (i->index < EDGE_COUNT (ei_container (*i)));
 445   i->index++;
 446 }
 447
 448 /* Move the iterator to the previous element.  */
 449 static inline void
 450 ei_prev (edge_iterator *i)
 451 {
 452   gcc_checking_assert (i->index > 0);
 453   i->index--;
 454 }
 455
 456 /* Return the edge pointed to by the iterator `i'.  */
 457 static inline edge
 458 ei_edge (edge_iterator i)
 459 {
 460   return EDGE_I (ei_container (i), i.index);
 461 }
 462
 463 /* Return an edge pointed to by the iterator.  Do it safely so that
 464    NULL is returned when the iterator is pointing at the end of the
 465    sequence.  */
 466 static inline edge
 467 ei_safe_edge (edge_iterator i)
 468 {
 469   return !ei_end_p (i) ? ei_edge (i) : NULL;
 470 }
 471
 472 /* Return 1 if we should continue to iterate.  Return 0 otherwise.
 473    *Edge P is set to the next edge if we are to continue to iterate
 474    and NULL otherwise.  */
 475
 476 static inline bool
 477 ei_cond (edge_iterator ei, edge *p)
 478 {
 479   if (!ei_end_p (ei))
 480     {
 481       *p = ei_edge (ei);
 482       return 1;
 483     }
 484   else
 485     {
 486       *p = NULL;
 487       return 0;
 488     }
 489 }
 490
 491 /* This macro serves as a convenient way to iterate each edge in a
 492    vector of predecessor or successor edges.  It must not be used when
 493    an element might be removed during the traversal, otherwise
 494    elements will be missed.  Instead, use a for-loop like that shown
 495    in the following pseudo-code:
 496
 497    FOR (ei = ei_start (bb->succs); (e = ei_safe_edge (ei)); )
 498      {
 499         IF (e != taken_edge)
 500           remove_edge (e);
 501         ELSE
 502           ei_next (&ei);
 503      }
 504 */
 505
 506 #define FOR_EACH_EDGE(EDGE,ITER,EDGE_VEC)       \
 507   for ((ITER) = ei_start ((EDGE_VEC));          \
 508        ei_cond ((ITER), &(EDGE));               \
 509        ei_next (&(ITER)))
 510
 511 #define CLEANUP_EXPENSIVE       1       /* Do relatively expensive optimizations
 512                                            except for edge forwarding */
 513 #define CLEANUP_CROSSJUMP       2       /* Do crossjumping.  */
 514 #define CLEANUP_POST_REGSTACK   4       /* We run after reg-stack and need
 515                                            to care REG_DEAD notes.  */
 516 #define CLEANUP_THREADING       8       /* Do jump threading.  */
 517 #define CLEANUP_NO_INSN_DEL     16      /* Do not try to delete trivially dead
 518                                            insns.  */
 519 #define CLEANUP_CFGLAYOUT       32      /* Do cleanup in cfglayout mode.  */
 520 #define CLEANUP_CFG_CHANGED     64      /* The caller changed the CFG.  */
 521
 522 /* Return true if BB is in a transaction.  */
 523
 524 static inline bool
 525 bb_in_transaction (basic_block bb)
 526 {
 527   return bb->flags & BB_IN_TRANSACTION;
 528 }
 529
 530 /* Return true when one of the predecessor edges of BB is marked with EDGE_EH.  */
 531 static inline bool
 532 bb_has_eh_pred (basic_block bb)
 533 {
 534   edge e;
 535   edge_iterator ei;
 536
 537   FOR_EACH_EDGE (e, ei, bb->preds)
 538     {
 539       if (e->flags & EDGE_EH)
 540         return true;
 541     }
 542   return false;
 543 }
 544
 545 /* Return true when one of the predecessor edges of BB is marked with EDGE_ABNORMAL.  */
 546 static inline bool
 547 bb_has_abnormal_pred (basic_block bb)
 548 {
 549   edge e;
 550   edge_iterator ei;
 551
 552   FOR_EACH_EDGE (e, ei, bb->preds)
 553     {
 554       if (e->flags & EDGE_ABNORMAL)
 555         return true;
 556     }
 557   return false;
 558 }
 559
 560 /* Return the fallthru edge in EDGES if it exists, NULL otherwise.  */
 561 static inline edge
 562 find_fallthru_edge (vec<edge, va_gc> *edges)
 563 {
 564   edge e;
 565   edge_iterator ei;
 566
 567   FOR_EACH_EDGE (e, ei, edges)
 568     if (e->flags & EDGE_FALLTHRU)
 569       break;
 570
 571   return e;
 572 }
 573
 574 /* Check tha probability is sane.  */
 575
 576 static inline void
 577 check_probability (int prob)
 578 {
 579   gcc_checking_assert (prob >= 0 && prob <= REG_BR_PROB_BASE);
 580 }
 581
 582 /* Given PROB1 and PROB2, return PROB1*PROB2/REG_BR_PROB_BASE.
 583    Used to combine BB probabilities.  */
 584
 585 static inline int
 586 combine_probabilities (int prob1, int prob2)
 587 {
 588   check_probability (prob1);
 589   check_probability (prob2);
 590   return RDIV (prob1 * prob2, REG_BR_PROB_BASE);
 591 }
 592
 593 /* Apply scale factor SCALE on frequency or count FREQ. Use this
 594    interface when potentially scaling up, so that SCALE is not
 595    constrained to be < REG_BR_PROB_BASE.  */
 596
 597 static inline gcov_type
 598 apply_scale (gcov_type freq, gcov_type scale)
 599 {
 600   return RDIV (freq * scale, REG_BR_PROB_BASE);
 601 }
 602
 603 /* Apply probability PROB on frequency or count FREQ.  */
 604
 605 static inline gcov_type
 606 apply_probability (gcov_type freq, int prob)
 607 {
 608   check_probability (prob);
 609   return apply_scale (freq, prob);
 610 }
 611
 612 /* Return inverse probability for PROB.  */
 613
 614 static inline int
 615 inverse_probability (int prob1)
 616 {
 617   check_probability (prob1);
 618   return REG_BR_PROB_BASE - prob1;
 619 }
 620
 621 /* Return true if BB has at least one abnormal outgoing edge.  */
 622
 623 static inline bool
 624 has_abnormal_or_eh_outgoing_edge_p (basic_block bb)
 625 {
 626   edge e;
 627   edge_iterator ei;
 628
 629   FOR_EACH_EDGE (e, ei, bb->succs)
 630     if (e->flags & (EDGE_ABNORMAL | EDGE_EH))
 631       return true;
 632
 633   return false;
 634 }
 635
 636 /* Return true when one of the predecessor edges of BB is marked with
 637    EDGE_ABNORMAL_CALL or EDGE_EH.  */
 638
 639 static inline bool
 640 has_abnormal_call_or_eh_pred_edge_p (basic_block bb)
 641 {
 642   edge e;
 643   edge_iterator ei;
 644
 645   FOR_EACH_EDGE (e, ei, bb->preds)
 646     if (e->flags & (EDGE_ABNORMAL_CALL | EDGE_EH))
 647       return true;
 648
 649   return false;
 650 }
 651
 652 #endif /* GCC_BASIC_BLOCK_H */