/buildworker/marxinbox-gcc-clang-static-analyzer/build/gcc/cfgloopmanip.cc

Bug Summary

File:	build/gcc/cfgloopmanip.cc
Warning:	line 567, column 4 Called C++ object pointer is null

Annotated Source Code

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clang -cc1 -cc1 -triple x86_64-suse-linux -analyze -disable-free -clear-ast-before-backend -disable-llvm-verifier -discard-value-names -main-file-name cfgloopmanip.cc -analyzer-checker=core -analyzer-checker=apiModeling -analyzer-checker=unix -analyzer-checker=deadcode -analyzer-checker=cplusplus -analyzer-checker=security.insecureAPI.UncheckedReturn -analyzer-checker=security.insecureAPI.getpw -analyzer-checker=security.insecureAPI.gets -analyzer-checker=security.insecureAPI.mktemp -analyzer-checker=security.insecureAPI.mkstemp -analyzer-checker=security.insecureAPI.vfork -analyzer-checker=nullability.NullPassedToNonnull -analyzer-checker=nullability.NullReturnedFromNonnull -analyzer-output plist -w -setup-static-analyzer -analyzer-config-compatibility-mode=true -mrelocation-model static -mframe-pointer=none -fmath-errno -ffp-contract=on -fno-rounding-math -mconstructor-aliases -funwind-tables=2 -target-cpu x86-64 -tune-cpu generic -debugger-tuning=gdb -fcoverage-compilation-dir=/buildworker/marxinbox-gcc-clang-static-analyzer/objdir/gcc -resource-dir /usr/lib64/clang/15.0.7 -D IN_GCC -D HAVE_CONFIG_H -I . -I . -I /buildworker/marxinbox-gcc-clang-static-analyzer/build/gcc -I /buildworker/marxinbox-gcc-clang-static-analyzer/build/gcc/. -I /buildworker/marxinbox-gcc-clang-static-analyzer/build/gcc/../include -I /buildworker/marxinbox-gcc-clang-static-analyzer/build/gcc/../libcpp/include -I /buildworker/marxinbox-gcc-clang-static-analyzer/build/gcc/../libcody -I /buildworker/marxinbox-gcc-clang-static-analyzer/build/gcc/../libdecnumber -I /buildworker/marxinbox-gcc-clang-static-analyzer/build/gcc/../libdecnumber/bid -I ../libdecnumber -I /buildworker/marxinbox-gcc-clang-static-analyzer/build/gcc/../libbacktrace -internal-isystem /usr/bin/../lib64/gcc/x86_64-suse-linux/13/../../../../include/c++/13 -internal-isystem /usr/bin/../lib64/gcc/x86_64-suse-linux/13/../../../../include/c++/13/x86_64-suse-linux -internal-isystem /usr/bin/../lib64/gcc/x86_64-suse-linux/13/../../../../include/c++/13/backward -internal-isystem /usr/lib64/clang/15.0.7/include -internal-isystem /usr/local/include -internal-isystem /usr/bin/../lib64/gcc/x86_64-suse-linux/13/../../../../x86_64-suse-linux/include -internal-externc-isystem /include -internal-externc-isystem /usr/include -O2 -Wno-narrowing -Wwrite-strings -Wno-long-long -Wno-variadic-macros -Wno-overlength-strings -fdeprecated-macro -fdebug-compilation-dir=/buildworker/marxinbox-gcc-clang-static-analyzer/objdir/gcc -ferror-limit 19 -fno-rtti -fgnuc-version=4.2.1 -vectorize-loops -vectorize-slp -analyzer-output=plist-html -analyzer-config silence-checkers=core.NullDereference -faddrsig -D__GCC_HAVE_DWARF2_CFI_ASM=1 -o /buildworker/marxinbox-gcc-clang-static-analyzer/objdir/clang-static-analyzer/2023-03-27-141847-20772-1/report-cTfdom.plist -x c++ /buildworker/marxinbox-gcc-clang-static-analyzer/build/gcc/cfgloopmanip.cc

/buildworker/marxinbox-gcc-clang-static-analyzer/build/gcc/cfgloopmanip.cc

→

1/* Loop manipulation code for GNU compiler.
 Copyright (C) 2002-2023 Free Software Foundation, Inc.

4This file is part of GCC.

6GCC is free software; you can redistribute it and/or modify it under
7the terms of the GNU General Public License as published by the Free
8Software Foundation; either version 3, or (at your option) any later
9version.

11GCC is distributed in the hope that it will be useful, but WITHOUT ANY
12WARRANTY; without even the implied warranty of MERCHANTABILITY or
13FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
14for more details.

16You should have received a copy of the GNU General Public License
17along with GCC; see the file COPYING3.  If not see
18<http://www.gnu.org/licenses/>.  */

20#include "config.h"
21#include "system.h"
22#include "coretypes.h"
23#include "backend.h"
24#include "rtl.h"
25#include "tree.h"
26#include "gimple.h"
27#include "cfghooks.h"
28#include "cfganal.h"
29#include "cfgloop.h"
30#include "gimple-iterator.h"
31#include "gimplify-me.h"
32#include "tree-ssa-loop-manip.h"
33#include "dumpfile.h"

35static void copy_loops_to (class loop **, int,
	   class loop *);
37static void loop_redirect_edge (edge, basic_block);
38static void remove_bbs (basic_block *, int);
39static bool rpe_enum_p (const_basic_block, const void *);
40static int find_path (edge, basic_block **);
41static void fix_loop_placements (class loop *, bool *);
42static bool fix_bb_placement (basic_block);
43static void fix_bb_placements (basic_block, bool *, bitmap);

45/* Checks whether basic block BB is dominated by DATA.  */
46static bool
47rpe_enum_p (const_basic_block bb, const void *data)
48{
return dominated_by_p (CDI_DOMINATORS, bb, (const_basic_block) data);
50}

52/* Remove basic blocks BBS.  NBBS is the number of the basic blocks.  */

54static void
55remove_bbs (basic_block *bbs, int nbbs)
56{
int i;

for (i = 0; i < nbbs; i++)
  delete_basic_block (bbs[i]);
61}

63/* Find path -- i.e. the basic blocks dominated by edge E and put them
 into array BBS, that will be allocated large enough to contain them.
 E->dest must have exactly one predecessor for this to work (it is
 easy to achieve and we do not put it here because we do not want to
 alter anything by this function).  The number of basic blocks in the
 path is returned.  */
69static int
70find_path (edge e, basic_block **bbs)
71{
gcc_assert (EDGE_COUNT (e->dest->preds) <= 1)((void)(!(vec_safe_length (e->dest->preds) <= 1) ? fancy_abort
 ("/buildworker/marxinbox-gcc-clang-static-analyzer/build/gcc/cfgloopmanip.cc"
, 72, __FUNCTION__), 0 : 0));

/* Find bbs in the path.  */
*bbs = XNEWVEC (basic_block, n_basic_blocks_for_fn (cfun))((basic_block *) xmalloc (sizeof (basic_block) * ((((cfun + 0
))->cfg->x_n_basic_blocks))));
return dfs_enumerate_from (e->dest, 0, rpe_enum_p, *bbs,
	     n_basic_blocks_for_fn (cfun)(((cfun + 0))->cfg->x_n_basic_blocks), e->dest);
78}

80/* Fix placement of basic block BB inside loop hierarchy --
 Let L be a loop to that BB belongs.  Then every successor of BB must either
   1) belong to some superloop of loop L, or
   2) be a header of loop K such that K->outer is superloop of L
 Returns true if we had to move BB into other loop to enforce this condition,
 false if the placement of BB was already correct (provided that placements
 of its successors are correct).  */
87static bool
88fix_bb_placement (basic_block bb)
89{
edge e;
edge_iterator ei;
class loop *loop = current_loops((cfun + 0)->x_current_loops)->tree_root, *act;

FOR_EACH_EDGE (e, ei, bb->succs)for ((ei) = ei_start_1 (&((bb->succs))); ei_cond ((ei)
, &(e)); ei_next (&(ei)))
  {
    if (e->dest == EXIT_BLOCK_PTR_FOR_FN (cfun)(((cfun + 0))->cfg->x_exit_block_ptr))
continue;

    act = e->dest->loop_father;
    if (act->header == e->dest)
act = loop_outer (act);

    if (flow_loop_nested_p (loop, act))
loop = act;
  }

if (loop == bb->loop_father)
  return false;

remove_bb_from_loops (bb);
add_bb_to_loop (bb, loop);

return true;
114}

116/* Fix placement of LOOP inside loop tree, i.e. find the innermost superloop
 of LOOP to that leads at least one exit edge of LOOP, and set it
 as the immediate superloop of LOOP.  Return true if the immediate superloop
 of LOOP changed.

 IRRED_INVALIDATED is set to true if a change in the loop structures might
 invalidate the information about irreducible regions.  */

124static bool
125fix_loop_placement (class loop *loop, bool *irred_invalidated)
126{
unsigned i;
edge e;
auto_vec<edge> exits = get_loop_exit_edges (loop);
class loop *father = current_loops((cfun + 0)->x_current_loops)->tree_root, *act;
bool ret = false;

FOR_EACH_VEC_ELT (exits, i, e)for (i = 0; (exits).iterate ((i), &(e)); ++(i))
  {
    act = find_common_loop (loop, e->dest->loop_father);
    if (flow_loop_nested_p (father, act))
father = act;
  }

if (father != loop_outer (loop))
  {
    for (act = loop_outer (loop); act != father; act = loop_outer (act))
act->num_nodes -= loop->num_nodes;
    flow_loop_tree_node_remove (loop);
    flow_loop_tree_node_add (father, loop);

    /* The exit edges of LOOP no longer exits its original immediate
superloops; remove them from the appropriate exit lists.  */
    FOR_EACH_VEC_ELT (exits, i, e)for (i = 0; (exits).iterate ((i), &(e)); ++(i))
{
 /* We may need to recompute irreducible loops.  */
 if (e->flags & EDGE_IRREDUCIBLE_LOOP)
   *irred_invalidated = true;
 rescan_loop_exit (e, false, false);
}

    ret = true;
  }

return ret;
161}

163/* Fix placements of basic blocks inside loop hierarchy stored in loops; i.e.
 enforce condition stated in description of fix_bb_placement. We
 start from basic block FROM that had some of its successors removed, so that
 his placement no longer has to be correct, and iteratively fix placement of
 its predecessors that may change if placement of FROM changed.  Also fix
 placement of subloops of FROM->loop_father, that might also be altered due
 to this change; the condition for them is similar, except that instead of
 successors we consider edges coming out of the loops.

 If the changes may invalidate the information about irreducible regions,
 IRRED_INVALIDATED is set to true.  

 If LOOP_CLOSED_SSA_INVLIDATED is non-zero then all basic blocks with
 changed loop_father are collected there. */

178static void
179fix_bb_placements (basic_block from,
   bool *irred_invalidated,
   bitmap loop_closed_ssa_invalidated)
182{
basic_block *queue, *qtop, *qbeg, *qend;
class loop *base_loop, *target_loop;
edge e;

/* We pass through blocks back-reachable from FROM, testing whether some
   of their successors moved to outer loop.  It may be necessary to
   iterate several times, but it is finite, as we stop unless we move
   the basic block up the loop structure.  The whole story is a bit
   more complicated due to presence of subloops, those are moved using
   fix_loop_placement.  */

base_loop = from->loop_father;
/* If we are already in the outermost loop, the basic blocks cannot be moved
   outside of it.  If FROM is the header of the base loop, it cannot be moved
   outside of it, either.  In both cases, we can end now.  */
if (base_loop == current_loops((cfun + 0)->x_current_loops)->tree_root
    || from == base_loop->header)
  return;

auto_sbitmap in_queue (last_basic_block_for_fn (cfun)(((cfun + 0))->cfg->x_last_basic_block));
bitmap_clear (in_queue);
bitmap_set_bit (in_queue, from->index);
/* Prevent us from going out of the base_loop.  */
bitmap_set_bit (in_queue, base_loop->header->index);

queue = XNEWVEC (basic_block, base_loop->num_nodes + 1)((basic_block *) xmalloc (sizeof (basic_block) * (base_loop->
num_nodes + 1)));
qtop = queue + base_loop->num_nodes + 1;
qbeg = queue;
qend = queue + 1;
*qbeg = from;

while (qbeg != qend)
  {
    edge_iterator ei;
    from = *qbeg;
    qbeg++;
    if (qbeg == qtop)
qbeg = queue;
    bitmap_clear_bit (in_queue, from->index);

    if (from->loop_father->header == from)
{
 /* Subloop header, maybe move the loop upward.  */
 if (!fix_loop_placement (from->loop_father, irred_invalidated))
   continue;
 target_loop = loop_outer (from->loop_father);
 if (loop_closed_ssa_invalidated)
   {
     basic_block *bbs = get_loop_body (from->loop_father);
     for (unsigned i = 0; i < from->loop_father->num_nodes; ++i)
bitmap_set_bit (loop_closed_ssa_invalidated, bbs[i]->index);
     free (bbs);
   }
}
    else
{
 /* Ordinary basic block.  */
 if (!fix_bb_placement (from))
   continue;
 target_loop = from->loop_father;
 if (loop_closed_ssa_invalidated)
   bitmap_set_bit (loop_closed_ssa_invalidated, from->index);
}

    FOR_EACH_EDGE (e, ei, from->succs)for ((ei) = ei_start_1 (&((from->succs))); ei_cond ((ei
), &(e)); ei_next (&(ei)))
{
 if (e->flags & EDGE_IRREDUCIBLE_LOOP)
   *irred_invalidated = true;
}

    /* Something has changed, insert predecessors into queue.  */
    FOR_EACH_EDGE (e, ei, from->preds)for ((ei) = ei_start_1 (&((from->preds))); ei_cond ((ei
), &(e)); ei_next (&(ei)))
{
 basic_block pred = e->src;
 class loop *nca;

 if (e->flags & EDGE_IRREDUCIBLE_LOOP)
   *irred_invalidated = true;

 if (bitmap_bit_p (in_queue, pred->index))
   continue;

 /* If it is subloop, then it either was not moved, or
    the path up the loop tree from base_loop do not contain
    it.  */
 nca = find_common_loop (pred->loop_father, base_loop);
 if (pred->loop_father != base_loop
     && (nca == base_loop
  || nca != pred->loop_father))
   pred = pred->loop_father->header;
 else if (!flow_loop_nested_p (target_loop, pred->loop_father))
   {
     /* If PRED is already higher in the loop hierarchy than the
 TARGET_LOOP to that we moved FROM, the change of the position
 of FROM does not affect the position of PRED, so there is no
 point in processing it.  */
     continue;
   }

 if (bitmap_bit_p (in_queue, pred->index))
   continue;

 /* Schedule the basic block.  */
 *qend = pred;
 qend++;
 if (qend == qtop)
   qend = queue;
 bitmap_set_bit (in_queue, pred->index);
}
  }
free (queue);
294}

296/* Removes path beginning at edge E, i.e. remove basic blocks dominated by E
 and update loop structures and dominators.  Return true if we were able
 to remove the path, false otherwise (and nothing is affected then).  */
299bool
300remove_path (edge e, bool *irred_invalidated,
    bitmap loop_closed_ssa_invalidated)
302{
edge ae;
basic_block *rem_bbs, *bord_bbs, from, bb;
vec<basic_block> dom_bbs;
int i, nrem, n_bord_bbs;
bool local_irred_invalidated = false;
edge_iterator ei;
class loop *l, *f;

if (! irred_invalidated)
  irred_invalidated = &local_irred_invalidated;

if (!can_remove_branch_p (e))
  return false;

/* Keep track of whether we need to update information about irreducible
   regions.  This is the case if the removed area is a part of the
   irreducible region, or if the set of basic blocks that belong to a loop
   that is inside an irreducible region is changed, or if such a loop is
   removed.  */
if (e->flags & EDGE_IRREDUCIBLE_LOOP)
  *irred_invalidated = true;

/* We need to check whether basic blocks are dominated by the edge
   e, but we only have basic block dominators.  This is easy to
   fix -- when e->dest has exactly one predecessor, this corresponds
   to blocks dominated by e->dest, if not, split the edge.  */
if (!single_pred_p (e->dest))
  e = single_pred_edge (split_edge (e));

/* It may happen that by removing path we remove one or more loops
   we belong to.  In this case first unloop the loops, then proceed
   normally.   We may assume that e->dest is not a header of any loop,
   as it now has exactly one predecessor.  */
for (l = e->src->loop_father; loop_outer (l); l = f)
  {
    f = loop_outer (l);
    if (dominated_by_p (CDI_DOMINATORS, l->latch, e->dest))
      unloop (l, irred_invalidated, loop_closed_ssa_invalidated);
  }

/* Identify the path.  */
nrem = find_path (e, &rem_bbs);

n_bord_bbs = 0;
bord_bbs = XNEWVEC (basic_block, n_basic_blocks_for_fn (cfun))((basic_block *) xmalloc (sizeof (basic_block) * ((((cfun + 0
))->cfg->x_n_basic_blocks))));
auto_sbitmap seen (last_basic_block_for_fn (cfun)(((cfun + 0))->cfg->x_last_basic_block));
bitmap_clear (seen);

/* Find "border" hexes -- i.e. those with predecessor in removed path.  */
for (i = 0; i < nrem; i++)
  bitmap_set_bit (seen, rem_bbs[i]->index);
if (!*irred_invalidated)
  FOR_EACH_EDGE (ae, ei, e->src->succs)for ((ei) = ei_start_1 (&((e->src->succs))); ei_cond
 ((ei), &(ae)); ei_next (&(ei)))
    if (ae != e && ae->dest != EXIT_BLOCK_PTR_FOR_FN (cfun)(((cfun + 0))->cfg->x_exit_block_ptr)
 && !bitmap_bit_p (seen, ae->dest->index)
 && ae->flags & EDGE_IRREDUCIBLE_LOOP)
{
 *irred_invalidated = true;
 break;
}

for (i = 0; i < nrem; i++)
  {
    FOR_EACH_EDGE (ae, ei, rem_bbs[i]->succs)for ((ei) = ei_start_1 (&((rem_bbs[i]->succs))); ei_cond
 ((ei), &(ae)); ei_next (&(ei)))
if (ae->dest != EXIT_BLOCK_PTR_FOR_FN (cfun)(((cfun + 0))->cfg->x_exit_block_ptr)
   && !bitmap_bit_p (seen, ae->dest->index))
 {
   bitmap_set_bit (seen, ae->dest->index);
   bord_bbs[n_bord_bbs++] = ae->dest;

   if (ae->flags & EDGE_IRREDUCIBLE_LOOP)
     *irred_invalidated = true;
 }
  }

/* Remove the path.  */
from = e->src;
remove_branch (e);
dom_bbs.create (0);

/* Cancel loops contained in the path.  */
for (i = 0; i < nrem; i++)
  if (rem_bbs[i]->loop_father->header == rem_bbs[i])
    cancel_loop_tree (rem_bbs[i]->loop_father);

remove_bbs (rem_bbs, nrem);
free (rem_bbs);

/* Find blocks whose dominators may be affected.  */
bitmap_clear (seen);
for (i = 0; i < n_bord_bbs; i++)
  {
    basic_block ldom;

    bb = get_immediate_dominator (CDI_DOMINATORS, bord_bbs[i]);
    if (bitmap_bit_p (seen, bb->index))
continue;
    bitmap_set_bit (seen, bb->index);

    for (ldom = first_dom_son (CDI_DOMINATORS, bb);
  ldom;
  ldom = next_dom_son (CDI_DOMINATORS, ldom))
if (!dominated_by_p (CDI_DOMINATORS, from, ldom))
 dom_bbs.safe_push (ldom);
  }

/* Recount dominators.  */
iterate_fix_dominators (CDI_DOMINATORS, dom_bbs, true);
dom_bbs.release ();
free (bord_bbs);

/* Fix placements of basic blocks inside loops and the placement of
   loops in the loop tree.  */
fix_bb_placements (from, irred_invalidated, loop_closed_ssa_invalidated);
fix_loop_placements (from->loop_father, irred_invalidated);

if (local_irred_invalidated
    && loops_state_satisfies_p (LOOPS_HAVE_MARKED_IRREDUCIBLE_REGIONS))
  mark_irreducible_loops ();

return true;
424}

426/* Creates place for a new LOOP in loops structure of FN.  */

428void
429place_new_loop (struct function *fn, class loop *loop)
430{
loop->num = number_of_loops (fn);
vec_safe_push (loops_for_fn (fn)->larray, loop);
433}

435/* Given LOOP structure with filled header and latch, find the body of the
 corresponding loop and add it to loops tree.  Insert the LOOP as a son of
 outer.  */

439void
440add_loop (class loop *loop, class loop *outer)
441{
basic_block *bbs;
int i, n;
class loop *subloop;
edge e;
edge_iterator ei;

/* Add it to loop structure.  */
place_new_loop (cfun(cfun + 0), loop);
flow_loop_tree_node_add (outer, loop);

/* Find its nodes.  */
bbs = XNEWVEC (basic_block, n_basic_blocks_for_fn (cfun))((basic_block *) xmalloc (sizeof (basic_block) * ((((cfun + 0
))->cfg->x_n_basic_blocks))));
n = get_loop_body_with_size (loop, bbs, n_basic_blocks_for_fn (cfun)(((cfun + 0))->cfg->x_n_basic_blocks));

for (i = 0; i < n; i++)
  {
    if (bbs[i]->loop_father == outer)
{
 remove_bb_from_loops (bbs[i]);
 add_bb_to_loop (bbs[i], loop);
 continue;
}

    loop->num_nodes++;

    /* If we find a direct subloop of OUTER, move it to LOOP.  */
    subloop = bbs[i]->loop_father;
    if (loop_outer (subloop) == outer
 && subloop->header == bbs[i])
{
 flow_loop_tree_node_remove (subloop);
 flow_loop_tree_node_add (loop, subloop);
}
  }

/* Update the information about loop exit edges.  */
for (i = 0; i < n; i++)
  {
    FOR_EACH_EDGE (e, ei, bbs[i]->succs)for ((ei) = ei_start_1 (&((bbs[i]->succs))); ei_cond (
(ei), &(e)); ei_next (&(ei)))
{
 rescan_loop_exit (e, false, false);
}
  }

free (bbs);
487}

489/* Scale profile of loop by P.  */

491void
492scale_loop_frequencies (class loop *loop, profile_probability p)
493{
basic_block *bbs;

bbs = get_loop_body (loop);
scale_bbs_frequencies (bbs, loop->num_nodes, p);
free (bbs);
499}

501/* Scale profile in LOOP by P.
 If ITERATION_BOUND is non-zero, scale even further if loop is predicted
 to iterate too many times.
 Before caling this function, preheader block profile should be already
 scaled to final count.  This is necessary because loop iterations are
 determined by comparing header edge count to latch ege count and thus
 they need to be scaled synchronously.  */

509void
510scale_loop_profile (class loop *loop, profile_probability p,
    gcov_type iteration_bound)
512{
edge e, preheader_e;
edge_iterator ei;

if (dump_file && (dump_flags & TDF_DETAILS))
1
Assuming 'dump_file' is null→
  {
    fprintf (dump_file, ";; Scaling loop %i with scale ",
      loop->num);
    p.dump (dump_file);
    fprintf (dump_file, " bounding iterations to %i\n",
      (int)iteration_bound);
  }

/* Scale the probabilities.  */
scale_loop_frequencies (loop, p);

if (iteration_bound == 0)
2
←
Assuming 'iteration_bound' is not equal to 0→
3
←
Taking false branch→
  return;

gcov_type iterations = expected_loop_iterations_unbounded (loop, NULLnullptr, true);

if (dump_file && (dump_flags & TDF_DETAILS))
4
←
Assuming 'dump_file' is null→
  {
    fprintf (dump_file, ";; guessed iterations after scaling %i\n",
      (int)iterations);
  }

/* See if loop is predicted to iterate too many times.  */
if (iterations <= iteration_bound)
5
←
Assuming 'iterations' is > 'iteration_bound'→
6
←
Taking false branch→
  return;

preheader_e = loop_preheader_edge (loop);

/* We could handle also loops without preheaders, but bounding is
   currently used only by optimizers that have preheaders constructed.  */
gcc_checking_assert (preheader_e)((void)(!(preheader_e) ? fancy_abort ("/buildworker/marxinbox-gcc-clang-static-analyzer/build/gcc/cfgloopmanip.cc"
, 547, __FUNCTION__), 0 : 0));
7
←
Assuming 'preheader_e' is non-null→
8
←
'?' condition is false→
profile_count count_in = preheader_e->count ();

if (count_in > profile_count::zero ()
9
←
Taking true branch→
    && loop->header->count.initialized_p ())
  {
    profile_count count_delta = profile_count::zero ();

    e = single_exit (loop);
    if (e)
10
←
Assuming 'e' is non-null→
11
←
Taking true branch→
{
 edge other_e;
 FOR_EACH_EDGE (other_e, ei, e->src->succs)for ((ei) = ei_start_1 (&((e->src->succs))); ei_cond
 ((ei), &(other_e)); ei_next (&(ei)))
12
←
Calling 'ei_cond'→
15
←
Returning from 'ei_cond'→
16
←
Loop condition is false. Execution continues on line 565→
   if (!(other_e->flags & (EDGE_ABNORMAL | EDGE_FAKE))
&& e != other_e)
     break;

 /* Probability of exit must be 1/iterations.  */
 count_delta = e->count ();
 e->probability = profile_probability::always () / iteration_bound;
 other_e->probability = e->probability.invert ();
17
←
Called C++ object pointer is null

 /* In code below we only handle the following two updates.  */
 if (other_e->dest != loop->header
     && other_e->dest != loop->latch
     && (dump_file && (dump_flags & TDF_DETAILS)))
   {
     fprintf (dump_file, ";; giving up on update of paths from "
       "exit condition to latch\n");
   }
}
    else
      if (dump_file && (dump_flags & TDF_DETAILS))
 fprintf (dump_file, ";; Loop has multiple exit edges; "
     		      "giving up on exit condition update\n");

    /* Roughly speaking we want to reduce the loop body profile by the
difference of loop iterations.  We however can do better if
we look at the actual profile, if it is available.  */
    p = profile_probability::always ();

    count_in *= iteration_bound;
    p = count_in.probability_in (loop->header->count);
    if (!(p > profile_probability::never ()))
p = profile_probability::very_unlikely ();

    if (p == profile_probability::always ()
 || !p.initialized_p ())
return;

    /* If latch exists, change its count, since we changed
probability of exit.  Theoretically we should update everything from
source of exit edge to latch, but for vectorizer this is enough.  */
    if (loop->latch && loop->latch != e->src)
loop->latch->count += count_delta;

    /* Scale the probabilities.  */
    scale_loop_frequencies (loop, p);

    /* Change latch's count back.  */
    if (loop->latch && loop->latch != e->src)
loop->latch->count -= count_delta;

    if (dump_file && (dump_flags & TDF_DETAILS))
fprintf (dump_file, ";; guessed iterations are now %i\n",
 (int)expected_loop_iterations_unbounded (loop, NULLnullptr, true));
  }
614}

616/* Recompute dominance information for basic blocks outside LOOP.  */

618static void
619update_dominators_in_loop (class loop *loop)
620{
vec<basic_block> dom_bbs = vNULL;
basic_block *body;
unsigned i;

auto_sbitmap seen (last_basic_block_for_fn (cfun)(((cfun + 0))->cfg->x_last_basic_block));
bitmap_clear (seen);
body = get_loop_body (loop);

for (i = 0; i < loop->num_nodes; i++)
  bitmap_set_bit (seen, body[i]->index);

for (i = 0; i < loop->num_nodes; i++)
  {
    basic_block ldom;

    for (ldom = first_dom_son (CDI_DOMINATORS, body[i]);
  ldom;
  ldom = next_dom_son (CDI_DOMINATORS, ldom))
if (!bitmap_bit_p (seen, ldom->index))
 {
   bitmap_set_bit (seen, ldom->index);
   dom_bbs.safe_push (ldom);
 }
  }

iterate_fix_dominators (CDI_DOMINATORS, dom_bbs, false);
free (body);
dom_bbs.release ();
649}

651/* Creates an if region as shown above. CONDITION is used to create
 the test for the if.

 |
 |     -------------                 -------------
 |     |  pred_bb  |                 |  pred_bb  |
 |     -------------                 -------------
 |           |                             |
 |           |                             | ENTRY_EDGE
 |           | ENTRY_EDGE                  V
 |           |             ====>     -------------
 |           |                       |  cond_bb  |
 |           |                       | CONDITION |
 |           |                       -------------
 |           V                        /         \
 |     -------------         e_false /           \ e_true
 |     |  succ_bb  |                V             V
 |     -------------         -----------       -----------
 |                           | false_bb |      | true_bb |
 |                           -----------       -----------
 |                                   \           /
 |                                    \         /
 |                                     V       V
 |                                   -------------
 |                                   |  join_bb  |
 |                                   -------------
 |                                         | exit_edge (result)
 |                                         V
 |                                    -----------
 |                                    | succ_bb |
 |                                    -----------
 |
*/

685edge
686create_empty_if_region_on_edge (edge entry_edge, tree condition)
687{

basic_block cond_bb, true_bb, false_bb, join_bb;
edge e_true, e_false, exit_edge;
gcond *cond_stmt;
tree simple_cond;
gimple_stmt_iterator gsi;

cond_bb = split_edge (entry_edge);

/* Insert condition in cond_bb.  */
gsi = gsi_last_bb (cond_bb);
simple_cond =
  force_gimple_operand_gsi (&gsi, condition, true, NULLnullptr,
	      false, GSI_NEW_STMT);
cond_stmt = gimple_build_cond_from_tree (simple_cond, NULL_TREE(tree) nullptr, NULL_TREE(tree) nullptr);
gsi = gsi_last_bb (cond_bb);
gsi_insert_after (&gsi, cond_stmt, GSI_NEW_STMT);

join_bb = split_edge (single_succ_edge (cond_bb));

e_true = single_succ_edge (cond_bb);
true_bb = split_edge (e_true);

e_false = make_edge (cond_bb, join_bb, 0);
false_bb = split_edge (e_false);

e_true->flags &= ~EDGE_FALLTHRU;
e_true->flags |= EDGE_TRUE_VALUE;
e_false->flags &= ~EDGE_FALLTHRU;
e_false->flags |= EDGE_FALSE_VALUE;

set_immediate_dominator (CDI_DOMINATORS, cond_bb, entry_edge->src);
set_immediate_dominator (CDI_DOMINATORS, true_bb, cond_bb);
set_immediate_dominator (CDI_DOMINATORS, false_bb, cond_bb);
set_immediate_dominator (CDI_DOMINATORS, join_bb, cond_bb);

exit_edge = single_succ_edge (join_bb);

if (single_pred_p (exit_edge->dest))
  set_immediate_dominator (CDI_DOMINATORS, exit_edge->dest, join_bb);

return exit_edge;
730}

732/* create_empty_loop_on_edge
 |
 |    - pred_bb -                   ------ pred_bb ------
 |   |           |                 | iv0 = initial_value |
 |    -----|-----                   ---------|-----------
 |         |                       ______    | entry_edge
 |         | entry_edge           /      |   |
 |         |             ====>   |      -V---V- loop_header -------------
 |         V                     |     | iv_before = phi (iv0, iv_after) |
 |    - succ_bb -                |      ---|-----------------------------
 |   |           |               |         |
 |    -----------                |      ---V--- loop_body ---------------
 |                               |     | iv_after = iv_before + stride   |
 |                               |     | if (iv_before < upper_bound)    |
 |                               |      ---|--------------\--------------
 |                               |         |               \ exit_e
 |                               |         V                \
 |                               |       - loop_latch -      V- succ_bb -
 |                               |      |              |     |           |
 |                               |       /-------------       -----------
 |                                \ ___ /

 Creates an empty loop as shown above, the IV_BEFORE is the SSA_NAME
 that is used before the increment of IV. IV_BEFORE should be used for
 adding code to the body that uses the IV.  OUTER is the outer loop in
 which the new loop should be inserted.

 Both INITIAL_VALUE and UPPER_BOUND expressions are gimplified and
 inserted on the loop entry edge.  This implies that this function
 should be used only when the UPPER_BOUND expression is a loop
 invariant.  */

764class loop *
765create_empty_loop_on_edge (edge entry_edge,
	   tree initial_value,
	   tree stride, tree upper_bound,
	   tree iv,
	   tree *iv_before,
	   tree *iv_after,
	   class loop *outer)
772{
basic_block loop_header, loop_latch, succ_bb, pred_bb;
class loop *loop;
gimple_stmt_iterator gsi;
gimple_seq stmts;
gcond *cond_expr;
tree exit_test;
edge exit_e;

gcc_assert (entry_edge && initial_value && stride && upper_bound && iv)((void)(!(entry_edge && initial_value && stride
 && upper_bound && iv) ? fancy_abort ("/buildworker/marxinbox-gcc-clang-static-analyzer/build/gcc/cfgloopmanip.cc"
, 781, __FUNCTION__), 0 : 0));

/* Create header, latch and wire up the loop.  */
pred_bb = entry_edge->src;
loop_header = split_edge (entry_edge);
loop_latch = split_edge (single_succ_edge (loop_header));
succ_bb = single_succ (loop_latch);
make_edge (loop_header, succ_bb, 0);
redirect_edge_succ_nodup (single_succ_edge (loop_latch), loop_header);

/* Set immediate dominator information.  */
set_immediate_dominator (CDI_DOMINATORS, loop_header, pred_bb);
set_immediate_dominator (CDI_DOMINATORS, loop_latch, loop_header);
set_immediate_dominator (CDI_DOMINATORS, succ_bb, loop_header);

/* Initialize a loop structure and put it in a loop hierarchy.  */
loop = alloc_loop ();
loop->header = loop_header;
loop->latch = loop_latch;
add_loop (loop, outer);

/* TODO: Fix counts.  */
scale_loop_frequencies (loop, profile_probability::even ());

/* Update dominators.  */
update_dominators_in_loop (loop);

/* Modify edge flags.  */
exit_e = single_exit (loop);
exit_e->flags = EDGE_LOOP_EXIT | EDGE_FALSE_VALUE;
single_pred_edge (loop_latch)->flags = EDGE_TRUE_VALUE;

/* Construct IV code in loop.  */
initial_value = force_gimple_operand (initial_value, &stmts, true, iv);
if (stmts)
  {
    gsi_insert_seq_on_edge (loop_preheader_edge (loop), stmts);
    gsi_commit_edge_inserts ();
  }

upper_bound = force_gimple_operand (upper_bound, &stmts, true, NULLnullptr);
if (stmts)
  {
    gsi_insert_seq_on_edge (loop_preheader_edge (loop), stmts);
    gsi_commit_edge_inserts ();
  }

gsi = gsi_last_bb (loop_header);
create_iv (initial_value, stride, iv, loop, &gsi, false,
    iv_before, iv_after);

/* Insert loop exit condition.  */
cond_expr = gimple_build_cond
  (LT_EXPR, *iv_before, upper_bound, NULL_TREE(tree) nullptr, NULL_TREE(tree) nullptr);

exit_test = gimple_cond_lhs (cond_expr);
exit_test = force_gimple_operand_gsi (&gsi, exit_test, true, NULLnullptr,
			false, GSI_NEW_STMT);
gimple_cond_set_lhs (cond_expr, exit_test);
gsi = gsi_last_bb (exit_e->src);
gsi_insert_after (&gsi, cond_expr, GSI_NEW_STMT);

split_block_after_labels (loop_header);

return loop;
846}

848/* Remove the latch edge of a LOOP and update loops to indicate that
 the LOOP was removed.  After this function, original loop latch will
 have no successor, which caller is expected to fix somehow.

 If this may cause the information about irreducible regions to become
 invalid, IRRED_INVALIDATED is set to true.  

 LOOP_CLOSED_SSA_INVALIDATED, if non-NULL, is a bitmap where we store
 basic blocks that had non-trivial update on their loop_father.*/

858void
859unloop (class loop *loop, bool *irred_invalidated,
bitmap loop_closed_ssa_invalidated)
861{
basic_block *body;
class loop *ploop;
unsigned i, n;
basic_block latch = loop->latch;
bool dummy = false;

if (loop_preheader_edge (loop)->flags & EDGE_IRREDUCIBLE_LOOP)
  *irred_invalidated = true;

/* This is relatively straightforward.  The dominators are unchanged, as
   loop header dominates loop latch, so the only thing we have to care of
   is the placement of loops and basic blocks inside the loop tree.  We
   move them all to the loop->outer, and then let fix_bb_placements do
   its work.  */

body = get_loop_body (loop);
n = loop->num_nodes;
for (i = 0; i < n; i++)
  if (body[i]->loop_father == loop)
    {
remove_bb_from_loops (body[i]);
add_bb_to_loop (body[i], loop_outer (loop));
    }
free (body);

while (loop->inner)
  {
    ploop = loop->inner;
    flow_loop_tree_node_remove (ploop);
    flow_loop_tree_node_add (loop_outer (loop), ploop);
  }

/* Remove the loop and free its data.  */
delete_loop (loop);

remove_edge (single_succ_edge (latch));

/* We do not pass IRRED_INVALIDATED to fix_bb_placements here, as even if
   there is an irreducible region inside the cancelled loop, the flags will
   be still correct.  */
fix_bb_placements (latch, &dummy, loop_closed_ssa_invalidated);
903}

905/* Fix placement of superloops of LOOP inside loop tree, i.e. ensure that
 condition stated in description of fix_loop_placement holds for them.
 It is used in case when we removed some edges coming out of LOOP, which
 may cause the right placement of LOOP inside loop tree to change.

 IRRED_INVALIDATED is set to true if a change in the loop structures might
 invalidate the information about irreducible regions.  */

913static void
914fix_loop_placements (class loop *loop, bool *irred_invalidated)
915{
class loop *outer;

while (loop_outer (loop))
  {
    outer = loop_outer (loop);
    if (!fix_loop_placement (loop, irred_invalidated))
break;

    /* Changing the placement of a loop in the loop tree may alter the
validity of condition 2) of the description of fix_bb_placement
for its preheader, because the successor is the header and belongs
to the loop.  So call fix_bb_placements to fix up the placement
of the preheader and (possibly) of its predecessors.  */
    fix_bb_placements (loop_preheader_edge (loop)->src,
	 irred_invalidated, NULLnullptr);
    loop = outer;
  }
933}

935/* Duplicate loop bounds and other information we store about
 the loop into its duplicate.  */

938void
939copy_loop_info (class loop *loop, class loop *target)
940{
gcc_checking_assert (!target->any_upper_bound && !target->any_estimate)((void)(!(!target->any_upper_bound && !target->
any_estimate) ? fancy_abort ("/buildworker/marxinbox-gcc-clang-static-analyzer/build/gcc/cfgloopmanip.cc"
, 941, __FUNCTION__), 0 : 0));
target->any_upper_bound = loop->any_upper_bound;
target->nb_iterations_upper_bound = loop->nb_iterations_upper_bound;
target->any_likely_upper_bound = loop->any_likely_upper_bound;
target->nb_iterations_likely_upper_bound
  = loop->nb_iterations_likely_upper_bound;
target->any_estimate = loop->any_estimate;
target->nb_iterations_estimate = loop->nb_iterations_estimate;
target->estimate_state = loop->estimate_state;
target->safelen = loop->safelen;
target->simdlen = loop->simdlen;
target->constraints = loop->constraints;
target->can_be_parallel = loop->can_be_parallel;
target->warned_aggressive_loop_optimizations
  |= loop->warned_aggressive_loop_optimizations;
target->dont_vectorize = loop->dont_vectorize;
target->force_vectorize = loop->force_vectorize;
target->in_oacc_kernels_region = loop->in_oacc_kernels_region;
target->finite_p = loop->finite_p;
target->unroll = loop->unroll;
target->owned_clique = loop->owned_clique;
962}

964/* Copies copy of LOOP as subloop of TARGET loop, placing newly
 created loop into loops structure.  If AFTER is non-null
 the new loop is added at AFTER->next, otherwise in front of TARGETs
 sibling list.  */
968class loop *
969duplicate_loop (class loop *loop, class loop *target, class loop *after)
970{
class loop *cloop;
cloop = alloc_loop ();
place_new_loop (cfun(cfun + 0), cloop);

copy_loop_info (loop, cloop);

/* Mark the new loop as copy of LOOP.  */
set_loop_copy (loop, cloop);

/* Add it to target.  */
flow_loop_tree_node_add (target, cloop, after);

return cloop;
984}

986/* Copies structure of subloops of LOOP into TARGET loop, placing
 newly created loops into loop tree at the end of TARGETs sibling
 list in the original order.  */
989void
990duplicate_subloops (class loop *loop, class loop *target)
991{
class loop *aloop, *cloop, *tail;

for (tail = target->inner; tail && tail->next; tail = tail->next)
  ;
for (aloop = loop->inner; aloop; aloop = aloop->next)
  {
    cloop = duplicate_loop (aloop, target, tail);
    tail = cloop;
    gcc_assert(!tail->next)((void)(!(!tail->next) ? fancy_abort ("/buildworker/marxinbox-gcc-clang-static-analyzer/build/gcc/cfgloopmanip.cc"
, 1000, __FUNCTION__), 0 : 0));
    duplicate_subloops (aloop, cloop);
  }
1003}

1005/* Copies structure of subloops of N loops, stored in array COPIED_LOOPS,
 into TARGET loop, placing newly created loops into loop tree adding
 them to TARGETs sibling list at the end in order.  */
1008static void
1009copy_loops_to (class loop **copied_loops, int n, class loop *target)
1010{
class loop *aloop, *tail;
int i;

for (tail = target->inner; tail && tail->next; tail = tail->next)
  ;
for (i = 0; i < n; i++)
  {
    aloop = duplicate_loop (copied_loops[i], target, tail);
    tail = aloop;
    gcc_assert(!tail->next)((void)(!(!tail->next) ? fancy_abort ("/buildworker/marxinbox-gcc-clang-static-analyzer/build/gcc/cfgloopmanip.cc"
, 1020, __FUNCTION__), 0 : 0));
    duplicate_subloops (copied_loops[i], aloop);
  }
1023}

1025/* Redirects edge E to basic block DEST.  */
1026static void
1027loop_redirect_edge (edge e, basic_block dest)
1028{
if (e->dest == dest)
  return;

redirect_edge_and_branch_force (e, dest);
1033}

1035/* Check whether LOOP's body can be duplicated.  */
1036bool
1037can_duplicate_loop_p (const class loop *loop)
1038{
int ret;
basic_block *bbs = get_loop_body (loop);

ret = can_copy_bbs_p (bbs, loop->num_nodes);
free (bbs);

return ret;
1046}

1048/* Duplicates body of LOOP to given edge E NDUPL times.  Takes care of updating
 loop structure and dominators (order of inner subloops is retained).
 E's destination must be LOOP header for this to work, i.e. it must be entry
 or latch edge of this loop; these are unique, as the loops must have
 preheaders for this function to work correctly (in case E is latch, the
 function unrolls the loop, if E is entry edge, it peels the loop).  Store
 edges created by copying ORIG edge from copies corresponding to set bits in
 WONT_EXIT bitmap (bit 0 corresponds to original LOOP body, the other copies
 are numbered in order given by control flow through them) into TO_REMOVE
 array.  Returns false if duplication is
 impossible.  */

1060bool
1061duplicate_loop_body_to_header_edge (class loop *loop, edge e,
		    unsigned int ndupl, sbitmap wont_exit,
		    edge orig, vec<edge> *to_remove, int flags)
1064{
class loop *target, *aloop;
class loop **orig_loops;
unsigned n_orig_loops;
basic_block header = loop->header, latch = loop->latch;
basic_block *new_bbs, *bbs, *first_active;
basic_block new_bb, bb, first_active_latch = NULLnullptr;
edge ae, latch_edge;
edge spec_edges[2], new_spec_edges[2];
const int SE_LATCH = 0;
const int SE_ORIG = 1;
unsigned i, j, n;
int is_latch = (latch == e->src);
profile_probability *scale_step = NULLnullptr;
profile_probability scale_main = profile_probability::always ();
profile_probability scale_act = profile_probability::always ();
profile_count after_exit_num = profile_count::zero (),
       after_exit_den = profile_count::zero ();
bool scale_after_exit = false;
int add_irreducible_flag;
basic_block place_after;
bitmap bbs_to_scale = NULLnullptr;
bitmap_iterator bi;

gcc_assert (e->dest == loop->header)((void)(!(e->dest == loop->header) ? fancy_abort ("/buildworker/marxinbox-gcc-clang-static-analyzer/build/gcc/cfgloopmanip.cc"
, 1088, __FUNCTION__), 0 : 0));
gcc_assert (ndupl > 0)((void)(!(ndupl > 0) ? fancy_abort ("/buildworker/marxinbox-gcc-clang-static-analyzer/build/gcc/cfgloopmanip.cc"
, 1089, __FUNCTION__), 0 : 0));

if (orig)
  {
    /* Orig must be edge out of the loop.  */
    gcc_assert (flow_bb_inside_loop_p (loop, orig->src))((void)(!(flow_bb_inside_loop_p (loop, orig->src)) ? fancy_abort
 ("/buildworker/marxinbox-gcc-clang-static-analyzer/build/gcc/cfgloopmanip.cc"
, 1094, __FUNCTION__), 0 : 0));
    gcc_assert (!flow_bb_inside_loop_p (loop, orig->dest))((void)(!(!flow_bb_inside_loop_p (loop, orig->dest)) ? fancy_abort
 ("/buildworker/marxinbox-gcc-clang-static-analyzer/build/gcc/cfgloopmanip.cc"
, 1095, __FUNCTION__), 0 : 0));
  }

n = loop->num_nodes;
bbs = get_loop_body_in_dom_order (loop);
gcc_assert (bbs[0] == loop->header)((void)(!(bbs[0] == loop->header) ? fancy_abort ("/buildworker/marxinbox-gcc-clang-static-analyzer/build/gcc/cfgloopmanip.cc"
, 1100, __FUNCTION__), 0 : 0));
gcc_assert (bbs[n  - 1] == loop->latch)((void)(!(bbs[n - 1] == loop->latch) ? fancy_abort ("/buildworker/marxinbox-gcc-clang-static-analyzer/build/gcc/cfgloopmanip.cc"
, 1101, __FUNCTION__), 0 : 0));

/* Check whether duplication is possible.  */
if (!can_copy_bbs_p (bbs, loop->num_nodes))
  {
    free (bbs);
    return false;
  }
new_bbs = XNEWVEC (basic_block, loop->num_nodes)((basic_block *) xmalloc (sizeof (basic_block) * (loop->num_nodes
)));

/* In case we are doing loop peeling and the loop is in the middle of
   irreducible region, the peeled copies will be inside it too.  */
add_irreducible_flag = e->flags & EDGE_IRREDUCIBLE_LOOP;
gcc_assert (!is_latch || !add_irreducible_flag)((void)(!(!is_latch || !add_irreducible_flag) ? fancy_abort (
"/buildworker/marxinbox-gcc-clang-static-analyzer/build/gcc/cfgloopmanip.cc"
, 1114, __FUNCTION__), 0 : 0));

/* Find edge from latch.  */
latch_edge = loop_latch_edge (loop);

if (flags & DLTHE_FLAG_UPDATE_FREQ1)
  {
    /* Calculate coefficients by that we have to scale counts
of duplicated loop bodies.  */
    profile_count count_in = header->count;
    profile_count count_le = latch_edge->count ();
    profile_count count_out_orig = orig ? orig->count () : count_in - count_le;
    profile_probability prob_pass_thru = count_le.probability_in (count_in);
    profile_probability prob_pass_wont_exit =
     (count_le + count_out_orig).probability_in (count_in);

    if (orig && orig->probability.initialized_p ()
 && !(orig->probability == profile_probability::always ()))
{
 /* The blocks that are dominated by a removed exit edge ORIG have
    frequencies scaled by this.  */
 if (orig->count ().initialized_p ())
   {
     after_exit_num = orig->src->count;
     after_exit_den = after_exit_num - orig->count ();
     scale_after_exit = true;
   }
 bbs_to_scale = BITMAP_ALLOCbitmap_alloc (NULLnullptr);
 for (i = 0; i < n; i++)
   {
     if (bbs[i] != orig->src
  && dominated_by_p (CDI_DOMINATORS, bbs[i], orig->src))
bitmap_set_bit (bbs_to_scale, i);
   }
}

    scale_step = XNEWVEC (profile_probability, ndupl)((profile_probability *) xmalloc (sizeof (profile_probability
) * (ndupl)));

    for (i = 1; i <= ndupl; i++)
scale_step[i - 1] = bitmap_bit_p (wont_exit, i)
		? prob_pass_wont_exit
		: prob_pass_thru;

    /* Complete peeling is special as the probability of exit in last
copy becomes 1.  */
    if (flags & DLTHE_FLAG_COMPLETTE_PEEL4)
{
 profile_count wanted_count = e->count ();

 gcc_assert (!is_latch)((void)(!(!is_latch) ? fancy_abort ("/buildworker/marxinbox-gcc-clang-static-analyzer/build/gcc/cfgloopmanip.cc"
, 1163, __FUNCTION__), 0 : 0));
 /* First copy has count of incoming edge.  Each subsequent
    count should be reduced by prob_pass_wont_exit.  Caller
    should've managed the flags so all except for original loop
    has won't exist set.  */
 scale_act = wanted_count.probability_in (count_in);
 /* Now simulate the duplication adjustments and compute header
    frequency of the last copy.  */
 for (i = 0; i < ndupl; i++)
   wanted_count = wanted_count.apply_probability (scale_step [i]);
 scale_main = wanted_count.probability_in (count_in);
}
    /* Here we insert loop bodies inside the loop itself (for loop unrolling).
First iteration will be original loop followed by duplicated bodies.
It is necessary to scale down the original so we get right overall
number of iterations.  */
    else if (is_latch)
{
 profile_probability prob_pass_main = bitmap_bit_p (wont_exit, 0)
					? prob_pass_wont_exit
					: prob_pass_thru;
 profile_probability p = prob_pass_main;
 profile_count scale_main_den = count_in;
 for (i = 0; i < ndupl; i++)
   {
     scale_main_den += count_in.apply_probability (p);
     p = p * scale_step[i];
   }
 /* If original loop is executed COUNT_IN times, the unrolled
    loop will account SCALE_MAIN_DEN times.  */
 scale_main = count_in.probability_in (scale_main_den);
 scale_act = scale_main * prob_pass_main;
}
    else
{
 profile_count preheader_count = e->count ();
 for (i = 0; i < ndupl; i++)
   scale_main = scale_main * scale_step[i];
 scale_act = preheader_count.probability_in (count_in);
}
  }

/* Loop the new bbs will belong to.  */
target = e->src->loop_father;

/* Original loops.  */
n_orig_loops = 0;
for (aloop = loop->inner; aloop; aloop = aloop->next)
  n_orig_loops++;
orig_loops = XNEWVEC (class loop *, n_orig_loops)((class loop * *) xmalloc (sizeof (class loop *) * (n_orig_loops
)));
for (aloop = loop->inner, i = 0; aloop; aloop = aloop->next, i++)
  orig_loops[i] = aloop;

set_loop_copy (loop, target);

first_active = XNEWVEC (basic_block, n)((basic_block *) xmalloc (sizeof (basic_block) * (n)));
if (is_latch)
  {
    memcpy (first_active, bbs, n * sizeof (basic_block));
    first_active_latch = latch;
  }

spec_edges[SE_ORIG] = orig;
spec_edges[SE_LATCH] = latch_edge;

place_after = e->src;
for (j = 0; j < ndupl; j++)
  {
    /* Copy loops.  */
    copy_loops_to (orig_loops, n_orig_loops, target);

    /* Copy bbs.  */
    copy_bbs (bbs, n, new_bbs, spec_edges, 2, new_spec_edges, loop,
place_after, true);
    place_after = new_spec_edges[SE_LATCH]->src;

    if (flags & DLTHE_RECORD_COPY_NUMBER2)
for (i = 0; i < n; i++)
 {
   gcc_assert (!new_bbs[i]->aux)((void)(!(!new_bbs[i]->aux) ? fancy_abort ("/buildworker/marxinbox-gcc-clang-static-analyzer/build/gcc/cfgloopmanip.cc"
, 1242, __FUNCTION__), 0 : 0));
   new_bbs[i]->aux = (void *)(size_t)(j + 1);
 }

    /* Note whether the blocks and edges belong to an irreducible loop.  */
    if (add_irreducible_flag)
{
 for (i = 0; i < n; i++)
   new_bbs[i]->flags |= BB_DUPLICATED;
 for (i = 0; i < n; i++)
   {
     edge_iterator ei;
     new_bb = new_bbs[i];
     if (new_bb->loop_father == target)
new_bb->flags |= BB_IRREDUCIBLE_LOOP;

     FOR_EACH_EDGE (ae, ei, new_bb->succs)for ((ei) = ei_start_1 (&((new_bb->succs))); ei_cond (
(ei), &(ae)); ei_next (&(ei)))
if ((ae->dest->flags & BB_DUPLICATED)
    && (ae->src->loop_father == target
	|| ae->dest->loop_father == target))
  ae->flags |= EDGE_IRREDUCIBLE_LOOP;
   }
 for (i = 0; i < n; i++)
   new_bbs[i]->flags &= ~BB_DUPLICATED;
}

    /* Redirect the special edges.  */
    if (is_latch)
{
 redirect_edge_and_branch_force (latch_edge, new_bbs[0]);
 redirect_edge_and_branch_force (new_spec_edges[SE_LATCH],
			  loop->header);
 set_immediate_dominator (CDI_DOMINATORS, new_bbs[0], latch);
 latch = loop->latch = new_bbs[n - 1];
 e = latch_edge = new_spec_edges[SE_LATCH];
}
    else
{
 redirect_edge_and_branch_force (new_spec_edges[SE_LATCH],
			  loop->header);
 redirect_edge_and_branch_force (e, new_bbs[0]);
 set_immediate_dominator (CDI_DOMINATORS, new_bbs[0], e->src);
 e = new_spec_edges[SE_LATCH];
}

    /* Record exit edge in this copy.  */
    if (orig && bitmap_bit_p (wont_exit, j + 1))
{
 if (to_remove)
   to_remove->safe_push (new_spec_edges[SE_ORIG]);
 force_edge_cold (new_spec_edges[SE_ORIG], true);

 /* Scale the frequencies of the blocks dominated by the exit.  */
 if (bbs_to_scale && scale_after_exit)
   {
     EXECUTE_IF_SET_IN_BITMAP (bbs_to_scale, 0, i, bi)for (bmp_iter_set_init (&(bi), (bbs_to_scale), (0), &
(i)); bmp_iter_set (&(bi), &(i)); bmp_iter_next (&
(bi), &(i)))
scale_bbs_frequencies_profile_count (new_bbs + i, 1, after_exit_num,
				     after_exit_den);
   }
}

    /* Record the first copy in the control flow order if it is not
the original loop (i.e. in case of peeling).  */
    if (!first_active_latch)
{
 memcpy (first_active, new_bbs, n * sizeof (basic_block));
 first_active_latch = new_bbs[n - 1];
}

    /* Set counts and frequencies.  */
    if (flags & DLTHE_FLAG_UPDATE_FREQ1)
{
 scale_bbs_frequencies (new_bbs, n, scale_act);
 scale_act = scale_act * scale_step[j];
}
  }
free (new_bbs);
free (orig_loops);

/* Record the exit edge in the original loop body, and update the frequencies.  */
if (orig && bitmap_bit_p (wont_exit, 0))
  {
    if (to_remove)
to_remove->safe_push (orig);
    force_edge_cold (orig, true);

    /* Scale the frequencies of the blocks dominated by the exit.  */
    if (bbs_to_scale && scale_after_exit)
{
 EXECUTE_IF_SET_IN_BITMAP (bbs_to_scale, 0, i, bi)for (bmp_iter_set_init (&(bi), (bbs_to_scale), (0), &
(i)); bmp_iter_set (&(bi), &(i)); bmp_iter_next (&
(bi), &(i)))
   scale_bbs_frequencies_profile_count (bbs + i, 1, after_exit_num,
				 after_exit_den);
}
  }

/* Update the original loop.  */
if (!is_latch)
  set_immediate_dominator (CDI_DOMINATORS, e->dest, e->src);
if (flags & DLTHE_FLAG_UPDATE_FREQ1)
  {
    scale_bbs_frequencies (bbs, n, scale_main);
    free (scale_step);
  }

/* Update dominators of outer blocks if affected.  */
for (i = 0; i < n; i++)
  {
    basic_block dominated, dom_bb;
    unsigned j;

    bb = bbs[i];

    auto_vec<basic_block> dom_bbs = get_dominated_by (CDI_DOMINATORS, bb);
    FOR_EACH_VEC_ELT (dom_bbs, j, dominated)for (j = 0; (dom_bbs).iterate ((j), &(dominated)); ++(j))
{
 if (flow_bb_inside_loop_p (loop, dominated))
   continue;
 dom_bb = nearest_common_dominator (
	CDI_DOMINATORS, first_active[i], first_active_latch);
 set_immediate_dominator (CDI_DOMINATORS, dominated, dom_bb);
}
  }
free (first_active);

free (bbs);
BITMAP_FREE (bbs_to_scale)((void) (bitmap_obstack_free ((bitmap) bbs_to_scale), (bbs_to_scale
) = (bitmap) nullptr));

return true;
1370}

1372/* A callback for make_forwarder block, to redirect all edges except for
 MFB_KJ_EDGE to the entry part.  E is the edge for that we should decide
 whether to redirect it.  */

1376edge mfb_kj_edge;
1377bool
1378mfb_keep_just (edge e)
1379{
return e != mfb_kj_edge;
1381}

1383/* True when a candidate preheader BLOCK has predecessors from LOOP.  */

1385static bool
1386has_preds_from_loop (basic_block block, class loop *loop)
1387{
edge e;
edge_iterator ei;

FOR_EACH_EDGE (e, ei, block->preds)for ((ei) = ei_start_1 (&((block->preds))); ei_cond ((
ei), &(e)); ei_next (&(ei)))
  if (e->src->loop_father == loop)
    return true;
return false;
1395}

1397/* Creates a pre-header for a LOOP.  Returns newly created block.  Unless
 CP_SIMPLE_PREHEADERS is set in FLAGS, we only force LOOP to have single
 entry; otherwise we also force preheader block to have only one successor.
 When CP_FALLTHRU_PREHEADERS is set in FLAGS, we force the preheader block
 to be a fallthru predecessor to the loop header and to have only
 predecessors from outside of the loop.
 The function also updates dominators.  */

1405basic_block
1406create_preheader (class loop *loop, int flags)
1407{
edge e;
basic_block dummy;
int nentry = 0;
bool irred = false;
bool latch_edge_was_fallthru;
edge one_succ_pred = NULLnullptr, single_entry = NULLnullptr;
edge_iterator ei;

FOR_EACH_EDGE (e, ei, loop->header->preds)for ((ei) = ei_start_1 (&((loop->header->preds))); ei_cond
 ((ei), &(e)); ei_next (&(ei)))
  {
    if (e->src == loop->latch)
continue;
    irred |= (e->flags & EDGE_IRREDUCIBLE_LOOP) != 0;
    nentry++;
    single_entry = e;
    if (single_succ_p (e->src))
one_succ_pred = e;
  }
gcc_assert (nentry)((void)(!(nentry) ? fancy_abort ("/buildworker/marxinbox-gcc-clang-static-analyzer/build/gcc/cfgloopmanip.cc"
, 1426, __FUNCTION__), 0 : 0));
if (nentry == 1)
  {
    bool need_forwarder_block = false;

    /* We do not allow entry block to be the loop preheader, since we
    cannot emit code there.  */
    if (single_entry->src == ENTRY_BLOCK_PTR_FOR_FN (cfun)(((cfun + 0))->cfg->x_entry_block_ptr))
      need_forwarder_block = true;
    else
      {
        /* If we want simple preheaders, also force the preheader to have
    just a single successor and a normal edge.  */
        if ((flags & CP_SIMPLE_PREHEADERS)
     && ((single_entry->flags & EDGE_COMPLEX(EDGE_ABNORMAL | EDGE_ABNORMAL_CALL | EDGE_EH | EDGE_PRESERVE
))
  || !single_succ_p (single_entry->src)))
          need_forwarder_block = true;
        /* If we want fallthru preheaders, also create forwarder block when
           preheader ends with a jump or has predecessors from loop.  */
        else if ((flags & CP_FALLTHRU_PREHEADERS)
                 && (JUMP_P (BB_END (single_entry->src))(((enum rtx_code) ((single_entry->src)->il.x.rtl->end_
)->code) == JUMP_INSN)
                     || has_preds_from_loop (single_entry->src, loop)))
          need_forwarder_block = true;
      }
    if (! need_forwarder_block)
return NULLnullptr;
  }

mfb_kj_edge = loop_latch_edge (loop);
latch_edge_was_fallthru = (mfb_kj_edge->flags & EDGE_FALLTHRU) != 0;
if (nentry == 1
    && ((flags & CP_FALLTHRU_PREHEADERS) == 0
	  || (single_entry->flags & EDGE_CROSSING) == 0))
  dummy = split_edge (single_entry);
else
  {
    edge fallthru = make_forwarder_block (loop->header, mfb_keep_just, NULLnullptr);
    dummy = fallthru->src;
    loop->header = fallthru->dest;
  }

/* Try to be clever in placing the newly created preheader.  The idea is to
   avoid breaking any "fallthruness" relationship between blocks.

   The preheader was created just before the header and all incoming edges
   to the header were redirected to the preheader, except the latch edge.
   So the only problematic case is when this latch edge was a fallthru
   edge: it is not anymore after the preheader creation so we have broken
   the fallthruness.  We're therefore going to look for a better place.  */
if (latch_edge_was_fallthru)
  {
    if (one_succ_pred)
e = one_succ_pred;
    else
e = EDGE_PRED (dummy, 0)(*(dummy)->preds)[(0)];

    move_block_after (dummy, e->src);
  }

if (irred)
  {
    dummy->flags |= BB_IRREDUCIBLE_LOOP;
    single_succ_edge (dummy)->flags |= EDGE_IRREDUCIBLE_LOOP;
  }

if (dump_file)
  fprintf (dump_file, "Created preheader block for loop %i\n",
    loop->num);

if (flags & CP_FALLTHRU_PREHEADERS)
  gcc_assert ((single_succ_edge (dummy)->flags & EDGE_FALLTHRU)((void)(!((single_succ_edge (dummy)->flags & EDGE_FALLTHRU
) && !(((enum rtx_code) ((dummy)->il.x.rtl->end_
)->code) == JUMP_INSN)) ? fancy_abort ("/buildworker/marxinbox-gcc-clang-static-analyzer/build/gcc/cfgloopmanip.cc"
, 1497, __FUNCTION__), 0 : 0))
              && !JUMP_P (BB_END (dummy)))((void)(!((single_succ_edge (dummy)->flags & EDGE_FALLTHRU
) && !(((enum rtx_code) ((dummy)->il.x.rtl->end_
)->code) == JUMP_INSN)) ? fancy_abort ("/buildworker/marxinbox-gcc-clang-static-analyzer/build/gcc/cfgloopmanip.cc"
, 1497, __FUNCTION__), 0 : 0));

return dummy;
1500}

1502/* Create preheaders for each loop; for meaning of FLAGS see create_preheader.  */

1504void
1505create_preheaders (int flags)
1506{
if (!current_loops((cfun + 0)->x_current_loops))
  return;

for (auto loop : loops_list (cfun(cfun + 0), 0))
  create_preheader (loop, flags);
loops_state_set (LOOPS_HAVE_PREHEADERS);
1513}

1515/* Forces all loop latches to have only single successor.  */

1517void
1518force_single_succ_latches (void)
1519{
edge e;

for (auto loop : loops_list (cfun(cfun + 0), 0))
  {
    if (loop->latch != loop->header && single_succ_p (loop->latch))
continue;

    e = find_edge (loop->latch, loop->header);
    gcc_checking_assert (e != NULL)((void)(!(e != nullptr) ? fancy_abort ("/buildworker/marxinbox-gcc-clang-static-analyzer/build/gcc/cfgloopmanip.cc"
, 1528, __FUNCTION__), 0 : 0));

    split_edge (e);
  }
loops_state_set (LOOPS_HAVE_SIMPLE_LATCHES);
1533}

1535/* This function is called from loop_version.  It splits the entry edge
 of the loop we want to version, adds the versioning condition, and
 adjust the edges to the two versions of the loop appropriately.
 e is an incoming edge. Returns the basic block containing the
 condition.

 --- edge e ---- > [second_head]

 Split it and insert new conditional expression and adjust edges.

  --- edge e ---> [cond expr] ---> [first_head]
	|
	+---------> [second_head]

THEN_PROB is the probability of then branch of the condition.
ELSE_PROB is the probability of else branch. Note that they may be both
REG_BR_PROB_BASE when condition is IFN_LOOP_VECTORIZED or
IFN_LOOP_DIST_ALIAS.  */

1554static basic_block
1555lv_adjust_loop_entry_edge (basic_block first_head, basic_block second_head,
	   edge e, void *cond_expr,
	   profile_probability then_prob,
	   profile_probability else_prob)
1559{
basic_block new_head = NULLnullptr;
edge e1;

gcc_assert (e->dest == second_head)((void)(!(e->dest == second_head) ? fancy_abort ("/buildworker/marxinbox-gcc-clang-static-analyzer/build/gcc/cfgloopmanip.cc"
, 1563, __FUNCTION__), 0 : 0));

/* Split edge 'e'. This will create a new basic block, where we can
   insert conditional expr.  */
new_head = split_edge (e);

lv_add_condition_to_bb (first_head, second_head, new_head,
	  cond_expr);

/* Don't set EDGE_TRUE_VALUE in RTL mode, as it's invalid there.  */
e = single_succ_edge (new_head);
e1 = make_edge (new_head, first_head,
  current_ir_type () == IR_GIMPLE ? EDGE_TRUE_VALUE : 0);
e1->probability = then_prob;
e->probability = else_prob;

set_immediate_dominator (CDI_DOMINATORS, first_head, new_head);
set_immediate_dominator (CDI_DOMINATORS, second_head, new_head);

/* Adjust loop header phi nodes.  */
lv_adjust_loop_header_phi (first_head, second_head, new_head, e1);

return new_head;
1586}

1588/* Main entry point for Loop Versioning transformation.

 This transformation given a condition and a loop, creates
 -if (condition) { loop_copy1 } else { loop_copy2 },
 where loop_copy1 is the loop transformed in one way, and loop_copy2
 is the loop transformed in another way (or unchanged). COND_EXPR
 may be a run time test for things that were not resolved by static
 analysis (overlapping ranges (anti-aliasing), alignment, etc.).

 If non-NULL, CONDITION_BB is set to the basic block containing the
 condition.

 THEN_PROB is the probability of the then edge of the if.  THEN_SCALE
 is the ratio by that the frequencies in the original loop should
 be scaled.  ELSE_SCALE is the ratio by that the frequencies in the
 new loop should be scaled.

 If PLACE_AFTER is true, we place the new loop after LOOP in the
 instruction stream, otherwise it is placed before LOOP.  */

1608class loop *
1609loop_version (class loop *loop,
     void *cond_expr, basic_block *condition_bb,
     profile_probability then_prob, profile_probability else_prob,
     profile_probability then_scale, profile_probability else_scale,
     bool place_after)
1614{
basic_block first_head, second_head;
edge entry, latch_edge;
int irred_flag;
class loop *nloop;
basic_block cond_bb;

/* Record entry and latch edges for the loop */
entry = loop_preheader_edge (loop);
irred_flag = entry->flags & EDGE_IRREDUCIBLE_LOOP;
entry->flags &= ~EDGE_IRREDUCIBLE_LOOP;

/* Note down head of loop as first_head.  */
first_head = entry->dest;

/* 1) Duplicate loop on the entry edge.  */
if (!cfg_hook_duplicate_loop_body_to_header_edge (loop, entry, 1, NULLnullptr, NULLnullptr,
				    NULLnullptr, 0))
  {
    entry->flags |= irred_flag;
    return NULLnullptr;
  }

/* 2) loopify the duplicated new loop. */
latch_edge = single_succ_edge (get_bb_copy (loop->latch));
nloop = alloc_loop ();
class loop *outer = loop_outer (latch_edge->dest->loop_father);
edge new_header_edge = single_pred_edge (get_bb_copy (loop->header));
nloop->header = new_header_edge->dest;
nloop->latch = latch_edge->src;
loop_redirect_edge (latch_edge, nloop->header);

/* Compute new loop.  */
add_loop (nloop, outer);
copy_loop_info (loop, nloop);
set_loop_copy (loop, nloop);

/* loopify redirected latch_edge. Update its PENDING_STMTS.  */
lv_flush_pending_stmts (latch_edge);

/* After duplication entry edge now points to new loop head block.
   Note down new head as second_head.  */
second_head = entry->dest;

/* 3) Split loop entry edge and insert new block with cond expr.  */
cond_bb =  lv_adjust_loop_entry_edge (first_head, second_head,
			entry, cond_expr, then_prob, else_prob);
if (condition_bb)
  *condition_bb = cond_bb;

if (!cond_bb)
  {
    entry->flags |= irred_flag;
    return NULLnullptr;
  }

/* Add cond_bb to appropriate loop.  */
if (cond_bb->loop_father)
  remove_bb_from_loops (cond_bb);
add_bb_to_loop (cond_bb, outer);

/* 4) Scale the original loop and new loop frequency.  */
scale_loop_frequencies (loop, then_scale);
scale_loop_frequencies (nloop, else_scale);
update_dominators_in_loop (loop);
update_dominators_in_loop (nloop);

/* Adjust irreducible flag.  */
if (irred_flag)
  {
    cond_bb->flags |= BB_IRREDUCIBLE_LOOP;
    loop_preheader_edge (loop)->flags |= EDGE_IRREDUCIBLE_LOOP;
    loop_preheader_edge (nloop)->flags |= EDGE_IRREDUCIBLE_LOOP;
    single_pred_edge (cond_bb)->flags |= EDGE_IRREDUCIBLE_LOOP;
  }

if (place_after)
  {
    basic_block *bbs = get_loop_body_in_dom_order (nloop), after;
    unsigned i;

    after = loop->latch;

    for (i = 0; i < nloop->num_nodes; i++)
{
 move_block_after (bbs[i], after);
 after = bbs[i];
}
    free (bbs);
  }

/* At this point condition_bb is loop preheader with two successors,
   first_head and second_head.   Make sure that loop preheader has only
   one successor.  */
split_edge (loop_preheader_edge (loop));
split_edge (loop_preheader_edge (nloop));

return nloop;
1712}

←

/buildworker/marxinbox-gcc-clang-static-analyzer/build/gcc/basic-block.h

1/* Define control flow data structures for the CFG.
2   Copyright (C) 1987-2023 Free Software Foundation, Inc.
3 
4This file is part of GCC.
5 
6GCC is free software; you can redistribute it and/or modify it under
7the terms of the GNU General Public License as published by the Free
8Software Foundation; either version 3, or (at your option) any later
9version.
10 
11GCC is distributed in the hope that it will be useful, but WITHOUT ANY
12WARRANTY; without even the implied warranty of MERCHANTABILITY or
13FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
14for more details.
15 
16You should have received a copy of the GNU General Public License
17along 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#include <profile-count.h>
24 
25/* Control flow edge information.  */
26class GTY((user)) edge_def {
27public:
28  /* The two blocks at the ends of the edge.  */
29  basic_block src;
30  basic_block dest;
31 
32  /* Instructions queued on the edge.  */
33  union edge_def_insns {
34    gimple_seq g;
35    rtx_insn *r;
36  } insns;
37 
38  /* Auxiliary info specific to a pass.  */
39  void *aux;
40 
41  /* Location of any goto implicit in the edge.  */
42  location_t goto_locus;
43 
44  /* The index number corresponding to this edge in the edge vector
45     dest->preds.  */
46  unsigned int dest_idx;
47 
48  int flags;			/* see cfg-flags.def */
49  profile_probability probability;
50 
51  /* Return count of edge E.  */
52  inline profile_count count () const;
53};
54 
55/* Masks for edge.flags.  */
56#define DEF_EDGE_FLAG(NAME,IDX) EDGE_##NAME = 1 << IDX ,
57enum cfg_edge_flags {
58#include "cfg-flags.def"
59  LAST_CFG_EDGE_FLAG		/* this is only used for EDGE_ALL_FLAGS */
60};
61#undef DEF_EDGE_FLAG
62 
63/* Bit mask for all edge flags.  */
64#define EDGE_ALL_FLAGS((LAST_CFG_EDGE_FLAG - 1) * 2 - 1)		((LAST_CFG_EDGE_FLAG - 1) * 2 - 1)
65 
66/* The following four flags all indicate something special about an edge.
67   Test the edge flags on EDGE_COMPLEX to detect all forms of "strange"
68   control flow transfers.  */
69#define EDGE_COMPLEX(EDGE_ABNORMAL | EDGE_ABNORMAL_CALL | EDGE_EH | EDGE_PRESERVE
) \
70  (EDGE_ABNORMAL | EDGE_ABNORMAL_CALL | EDGE_EH | EDGE_PRESERVE)
71 
72struct GTY(()) rtl_bb_info {
73  /* The first insn of the block is embedded into bb->il.x.  */
74  /* The last insn of the block.  */
75  rtx_insn *end_;
76 
77  /* In CFGlayout mode points to insn notes/jumptables to be placed just before
78     and after the block.   */
79  rtx_insn *header_;
80  rtx_insn *footer_;
81};
82 
83struct GTY(()) gimple_bb_info {
84  /* Sequence of statements in this block.  */
85  gimple_seq seq;
86 
87  /* PHI nodes for this block.  */
88  gimple_seq phi_nodes;
89};
90 
91/* A basic block is a sequence of instructions with only one entry and
92   only one exit.  If any one of the instructions are executed, they
93   will all be executed, and in sequence from first to last.
94 
95   There may be COND_EXEC instructions in the basic block.  The
96   COND_EXEC *instructions* will be executed -- but if the condition
97   is false the conditionally executed *expressions* will of course
98   not be executed.  We don't consider the conditionally executed
99   expression (which might have side-effects) to be in a separate
100   basic block because the program counter will always be at the same
101   location after the COND_EXEC instruction, regardless of whether the
102   condition is true or not.
103 
104   Basic blocks need not start with a label nor end with a jump insn.
105   For example, a previous basic block may just "conditionally fall"
106   into the succeeding basic block, and the last basic block need not
107   end with a jump insn.  Block 0 is a descendant of the entry block.
108 
109   A basic block beginning with two labels cannot have notes between
110   the labels.
111 
112   Data for jump tables are stored in jump_insns that occur in no
113   basic block even though these insns can follow or precede insns in
114   basic blocks.  */
115 
116/* Basic block information indexed by block number.  */
117struct GTY((chain_next ("%h.next_bb"), chain_prev ("%h.prev_bb"))) basic_block_def {
118  /* The edges into and out of the block.  */
119  vec<edge, va_gc> *preds;
120  vec<edge, va_gc> *succs;
121 
122  /* Auxiliary info specific to a pass.  */
123  void *GTY ((skip (""))) aux;
124 
125  /* Innermost loop containing the block.  */
126  class loop *loop_father;
127 
128  /* The dominance and postdominance information node.  */
129  struct et_node * GTY ((skip (""))) dom[2];
130 
131  /* Previous and next blocks in the chain.  */
132  basic_block prev_bb;
133  basic_block next_bb;
134 
135  union basic_block_il_dependent {
136      struct gimple_bb_info GTY ((tag ("0"))) gimple;
137      struct {
138        rtx_insn *head_;
139        struct rtl_bb_info * rtl;
140      } GTY ((tag ("1"))) x;
141    } GTY ((desc ("((%1.flags & BB_RTL) != 0)"))) il;
142 
143  /* Various flags.  See cfg-flags.def.  */
144  int flags;
145 
146  /* The index of this block.  */
147  int index;
148 
149  /* Expected number of executions: calculated in profile.cc.  */
150  profile_count count;
151};
152 
153/* This ensures that struct gimple_bb_info is smaller than
154   struct rtl_bb_info, so that inlining the former into basic_block_def
155   is the better choice.  */
156STATIC_ASSERT (sizeof (rtl_bb_info) >= sizeof (gimple_bb_info))static_assert ((sizeof (rtl_bb_info) >= sizeof (gimple_bb_info
)), "sizeof (rtl_bb_info) >= sizeof (gimple_bb_info)");
157 
158#define BB_FREQ_MAX10000 10000
159 
160/* Masks for basic_block.flags.  */
161#define DEF_BASIC_BLOCK_FLAG(NAME,IDX) BB_##NAME = 1 << IDX ,
162enum cfg_bb_flags
163{
164#include "cfg-flags.def"
165  LAST_CFG_BB_FLAG		/* this is only used for BB_ALL_FLAGS */
166};
167#undef DEF_BASIC_BLOCK_FLAG
168 
169/* Bit mask for all basic block flags.  */
170#define BB_ALL_FLAGS((LAST_CFG_BB_FLAG - 1) * 2 - 1)		((LAST_CFG_BB_FLAG - 1) * 2 - 1)
171 
172/* Bit mask for all basic block flags that must be preserved.  These are
173   the bit masks that are *not* cleared by clear_bb_flags.  */
174#define BB_FLAGS_TO_PRESERVE(BB_DISABLE_SCHEDULE | BB_RTL | BB_NON_LOCAL_GOTO_TARGET | BB_HOT_PARTITION
 | BB_COLD_PARTITION)					\
175  (BB_DISABLE_SCHEDULE | BB_RTL | BB_NON_LOCAL_GOTO_TARGET	\
176   | BB_HOT_PARTITION | BB_COLD_PARTITION)
177 
178/* Dummy bitmask for convenience in the hot/cold partitioning code.  */
179#define BB_UNPARTITIONED0	0
180 
181/* Partitions, to be used when partitioning hot and cold basic blocks into
182   separate sections.  */
183#define BB_PARTITION(bb)((bb)->flags & (BB_HOT_PARTITION|BB_COLD_PARTITION)) ((bb)->flags & (BB_HOT_PARTITION|BB_COLD_PARTITION))
184#define BB_SET_PARTITION(bb, part)do { basic_block bb_ = (bb); bb_->flags = ((bb_->flags &
 ~(BB_HOT_PARTITION|BB_COLD_PARTITION)) | (part)); } while (0
) do {					\
185  basic_block bb_ = (bb);						\
186  bb_->flags = ((bb_->flags & ~(BB_HOT_PARTITION|BB_COLD_PARTITION))	\
187		| (part));						\
188} while (0)
189 
190#define BB_COPY_PARTITION(dstbb, srcbb)do { basic_block bb_ = (dstbb); bb_->flags = ((bb_->flags
 & ~(BB_HOT_PARTITION|BB_COLD_PARTITION)) | (((srcbb)->
flags & (BB_HOT_PARTITION|BB_COLD_PARTITION)))); } while (
0) \
191  BB_SET_PARTITION (dstbb, BB_PARTITION (srcbb))do { basic_block bb_ = (dstbb); bb_->flags = ((bb_->flags
 & ~(BB_HOT_PARTITION|BB_COLD_PARTITION)) | (((srcbb)->
flags & (BB_HOT_PARTITION|BB_COLD_PARTITION)))); } while (
0)
192 
193/* Defines for accessing the fields of the CFG structure for function FN.  */
194#define ENTRY_BLOCK_PTR_FOR_FN(FN)((FN)->cfg->x_entry_block_ptr)	     ((FN)->cfg->x_entry_block_ptr)
195#define EXIT_BLOCK_PTR_FOR_FN(FN)((FN)->cfg->x_exit_block_ptr)	     ((FN)->cfg->x_exit_block_ptr)
196#define basic_block_info_for_fn(FN)((FN)->cfg->x_basic_block_info)	     ((FN)->cfg->x_basic_block_info)
197#define n_basic_blocks_for_fn(FN)((FN)->cfg->x_n_basic_blocks)	     ((FN)->cfg->x_n_basic_blocks)
198#define n_edges_for_fn(FN)((FN)->cfg->x_n_edges)		     ((FN)->cfg->x_n_edges)
199#define last_basic_block_for_fn(FN)((FN)->cfg->x_last_basic_block)	     ((FN)->cfg->x_last_basic_block)
200#define label_to_block_map_for_fn(FN)((FN)->cfg->x_label_to_block_map)	     ((FN)->cfg->x_label_to_block_map)
201#define profile_status_for_fn(FN)((FN)->cfg->x_profile_status)	     ((FN)->cfg->x_profile_status)
202 
203#define BASIC_BLOCK_FOR_FN(FN,N)((*((FN)->cfg->x_basic_block_info))[(N)]) \
204  ((*basic_block_info_for_fn (FN)((FN)->cfg->x_basic_block_info))[(N)])
205#define SET_BASIC_BLOCK_FOR_FN(FN,N,BB)((*((FN)->cfg->x_basic_block_info))[(N)] = (BB)) \
206  ((*basic_block_info_for_fn (FN)((FN)->cfg->x_basic_block_info))[(N)] = (BB))
207 
208/* For iterating over basic blocks.  */
209#define FOR_BB_BETWEEN(BB, FROM, TO, DIR)for (BB = FROM; BB != TO; BB = BB->DIR) \
210  for (BB = FROM; BB != TO; BB = BB->DIR)
211 
212#define FOR_EACH_BB_FN(BB, FN)for (BB = (FN)->cfg->x_entry_block_ptr->next_bb; BB !=
 (FN)->cfg->x_exit_block_ptr; BB = BB->next_bb) \
213  FOR_BB_BETWEEN (BB, (FN)->cfg->x_entry_block_ptr->next_bb, (FN)->cfg->x_exit_block_ptr, next_bb)for (BB = (FN)->cfg->x_entry_block_ptr->next_bb; BB !=
 (FN)->cfg->x_exit_block_ptr; BB = BB->next_bb)
214 
215#define FOR_EACH_BB_REVERSE_FN(BB, FN)for (BB = (FN)->cfg->x_exit_block_ptr->prev_bb; BB !=
 (FN)->cfg->x_entry_block_ptr; BB = BB->prev_bb) \
216  FOR_BB_BETWEEN (BB, (FN)->cfg->x_exit_block_ptr->prev_bb, (FN)->cfg->x_entry_block_ptr, prev_bb)for (BB = (FN)->cfg->x_exit_block_ptr->prev_bb; BB !=
 (FN)->cfg->x_entry_block_ptr; BB = BB->prev_bb)
217 
218/* For iterating over insns in basic block.  */
219#define FOR_BB_INSNS(BB, INSN)for ((INSN) = (BB)->il.x.head_; (INSN) && (INSN) !=
 NEXT_INSN ((BB)->il.x.rtl->end_); (INSN) = NEXT_INSN (
INSN))			\
220  for ((INSN) = BB_HEAD (BB)(BB)->il.x.head_;			\
221       (INSN) && (INSN) != NEXT_INSN (BB_END (BB)(BB)->il.x.rtl->end_);	\
222       (INSN) = NEXT_INSN (INSN))
223 
224/* For iterating over insns in basic block when we might remove the
225   current insn.  */
226#define FOR_BB_INSNS_SAFE(BB, INSN, CURR)for ((INSN) = (BB)->il.x.head_, (CURR) = (INSN) ? NEXT_INSN
 ((INSN)): nullptr; (INSN) && (INSN) != NEXT_INSN ((BB
)->il.x.rtl->end_); (INSN) = (CURR), (CURR) = (INSN) ? NEXT_INSN
 ((INSN)) : nullptr)			\
227  for ((INSN) = BB_HEAD (BB)(BB)->il.x.head_, (CURR) = (INSN) ? NEXT_INSN ((INSN)): NULLnullptr;	\
228       (INSN) && (INSN) != NEXT_INSN (BB_END (BB)(BB)->il.x.rtl->end_);	\
229       (INSN) = (CURR), (CURR) = (INSN) ? NEXT_INSN ((INSN)) : NULLnullptr)
230 
231#define FOR_BB_INSNS_REVERSE(BB, INSN)for ((INSN) = (BB)->il.x.rtl->end_; (INSN) && (
INSN) != PREV_INSN ((BB)->il.x.head_); (INSN) = PREV_INSN (
INSN))		\
232  for ((INSN) = BB_END (BB)(BB)->il.x.rtl->end_;			\
233       (INSN) && (INSN) != PREV_INSN (BB_HEAD (BB)(BB)->il.x.head_);	\
234       (INSN) = PREV_INSN (INSN))
235 
236#define FOR_BB_INSNS_REVERSE_SAFE(BB, INSN, CURR)for ((INSN) = (BB)->il.x.rtl->end_,(CURR) = (INSN) ? PREV_INSN
 ((INSN)) : nullptr; (INSN) && (INSN) != PREV_INSN ((
BB)->il.x.head_); (INSN) = (CURR), (CURR) = (INSN) ? PREV_INSN
 ((INSN)) : nullptr)	\
237  for ((INSN) = BB_END (BB)(BB)->il.x.rtl->end_,(CURR) = (INSN) ? PREV_INSN ((INSN)) : NULLnullptr;	\
238       (INSN) && (INSN) != PREV_INSN (BB_HEAD (BB)(BB)->il.x.head_);	\
239       (INSN) = (CURR), (CURR) = (INSN) ? PREV_INSN ((INSN)) : NULLnullptr)
240 
241/* Cycles through _all_ basic blocks, even the fake ones (entry and
242   exit block).  */
243 
244#define FOR_ALL_BB_FN(BB, FN)for (BB = ((FN)->cfg->x_entry_block_ptr); BB; BB = BB->
next_bb) \
245  for (BB = ENTRY_BLOCK_PTR_FOR_FN (FN)((FN)->cfg->x_entry_block_ptr); BB; BB = BB->next_bb)
246 
247
248/* Stuff for recording basic block info.  */
249 
250/* For now, these will be functions (so that they can include checked casts
251   to rtx_insn.   Once the underlying fields are converted from rtx
252   to rtx_insn, these can be converted back to macros.  */
253 
254#define BB_HEAD(B)(B)->il.x.head_      (B)->il.x.head_
255#define BB_END(B)(B)->il.x.rtl->end_       (B)->il.x.rtl->end_
256#define BB_HEADER(B)(B)->il.x.rtl->header_    (B)->il.x.rtl->header_
257#define BB_FOOTER(B)(B)->il.x.rtl->footer_    (B)->il.x.rtl->footer_
258 
259/* Special block numbers [markers] for entry and exit.
260   Neither of them is supposed to hold actual statements.  */
261#define ENTRY_BLOCK(0) (0)
262#define EXIT_BLOCK(1) (1)
263 
264/* The two blocks that are always in the cfg.  */
265#define NUM_FIXED_BLOCKS(2) (2)
266 
267/* This is the value which indicates no edge is present.  */
268#define EDGE_INDEX_NO_EDGE-1	-1
269 
270/* EDGE_INDEX returns an integer index for an edge, or EDGE_INDEX_NO_EDGE
271   if there is no edge between the 2 basic blocks.  */
272#define EDGE_INDEX(el, pred, succ)(find_edge_index ((el), (pred), (succ))) (find_edge_index ((el), (pred), (succ)))
273 
274/* INDEX_EDGE_PRED_BB and INDEX_EDGE_SUCC_BB return a pointer to the basic
275   block which is either the pred or succ end of the indexed edge.  */
276#define INDEX_EDGE_PRED_BB(el, index)((el)->index_to_edge[(index)]->src)	((el)->index_to_edge[(index)]->src)
277#define INDEX_EDGE_SUCC_BB(el, index)((el)->index_to_edge[(index)]->dest)	((el)->index_to_edge[(index)]->dest)
278 
279/* INDEX_EDGE returns a pointer to the edge.  */
280#define INDEX_EDGE(el, index)((el)->index_to_edge[(index)])           ((el)->index_to_edge[(index)])
281 
282/* Number of edges in the compressed edge list.  */
283#define NUM_EDGES(el)((el)->num_edges)			((el)->num_edges)
284 
285/* BB is assumed to contain conditional jump.  Return the fallthru edge.  */
286#define FALLTHRU_EDGE(bb)((*((bb))->succs)[(0)]->flags & EDGE_FALLTHRU ? (*(
(bb))->succs)[(0)] : (*((bb))->succs)[(1)])		(EDGE_SUCC ((bb), 0)(*((bb))->succs)[(0)]->flags & EDGE_FALLTHRU \
287					 ? EDGE_SUCC ((bb), 0)(*((bb))->succs)[(0)] : EDGE_SUCC ((bb), 1)(*((bb))->succs)[(1)])
288 
289/* BB is assumed to contain conditional jump.  Return the branch edge.  */
290#define BRANCH_EDGE(bb)((*((bb))->succs)[(0)]->flags & EDGE_FALLTHRU ? (*(
(bb))->succs)[(1)] : (*((bb))->succs)[(0)])			(EDGE_SUCC ((bb), 0)(*((bb))->succs)[(0)]->flags & EDGE_FALLTHRU \
291					 ? EDGE_SUCC ((bb), 1)(*((bb))->succs)[(1)] : EDGE_SUCC ((bb), 0)(*((bb))->succs)[(0)])
292 
293/* Return expected execution frequency of the edge E.  */
294#define EDGE_FREQUENCY(e)e->count ().to_frequency ((cfun + 0))		e->count ().to_frequency (cfun(cfun + 0))
295 
296/* Compute a scale factor (or probability) suitable for scaling of
297   gcov_type values via apply_probability() and apply_scale().  */
298#define GCOV_COMPUTE_SCALE(num,den)((den) ? ((((num) * 10000) + ((den)) / 2) / ((den))) : 10000) \
299  ((den) ? RDIV ((num) * REG_BR_PROB_BASE, (den))((((num) * 10000) + ((den)) / 2) / ((den))) : REG_BR_PROB_BASE10000)
300 
301/* Return nonzero if edge is critical.  */
302#define EDGE_CRITICAL_P(e)(vec_safe_length ((e)->src->succs) >= 2 && vec_safe_length
 ((e)->dest->preds) >= 2)		(EDGE_COUNT ((e)->src->succs)vec_safe_length ((e)->src->succs) >= 2 \
303					 && EDGE_COUNT ((e)->dest->preds)vec_safe_length ((e)->dest->preds) >= 2)
304 
305#define EDGE_COUNT(ev)vec_safe_length (ev)			vec_safe_length (ev)
306#define EDGE_I(ev,i)(*ev)[(i)]			(*ev)[(i)]
307#define EDGE_PRED(bb,i)(*(bb)->preds)[(i)]			(*(bb)->preds)[(i)]
308#define EDGE_SUCC(bb,i)(*(bb)->succs)[(i)]			(*(bb)->succs)[(i)]
309 
310/* Returns true if BB has precisely one successor.  */
311 
312inline bool
313single_succ_p (const_basic_block bb)
314{
315  return EDGE_COUNT (bb->succs)vec_safe_length (bb->succs) == 1;
316}
317 
318/* Returns true if BB has precisely one predecessor.  */
319 
320inline bool
321single_pred_p (const_basic_block bb)
322{
323  return EDGE_COUNT (bb->preds)vec_safe_length (bb->preds) == 1;
324}
325 
326/* Returns the single successor edge of basic block BB.  Aborts if
327   BB does not have exactly one successor.  */
328 
329inline edge
330single_succ_edge (const_basic_block bb)
331{
332  gcc_checking_assert (single_succ_p (bb))((void)(!(single_succ_p (bb)) ? fancy_abort ("/buildworker/marxinbox-gcc-clang-static-analyzer/build/gcc/basic-block.h"
, 332, __FUNCTION__), 0 : 0));
333  return EDGE_SUCC (bb, 0)(*(bb)->succs)[(0)];
334}
335 
336/* Returns the single predecessor edge of basic block BB.  Aborts
337   if BB does not have exactly one predecessor.  */
338 
339inline edge
340single_pred_edge (const_basic_block bb)
341{
342  gcc_checking_assert (single_pred_p (bb))((void)(!(single_pred_p (bb)) ? fancy_abort ("/buildworker/marxinbox-gcc-clang-static-analyzer/build/gcc/basic-block.h"
, 342, __FUNCTION__), 0 : 0));
343  return EDGE_PRED (bb, 0)(*(bb)->preds)[(0)];
344}
345 
346/* Returns the single successor block of basic block BB.  Aborts
347   if BB does not have exactly one successor.  */
348 
349inline basic_block
350single_succ (const_basic_block bb)
351{
352  return single_succ_edge (bb)->dest;
353}
354 
355/* Returns the single predecessor block of basic block BB.  Aborts
356   if BB does not have exactly one predecessor.*/
357 
358inline basic_block
359single_pred (const_basic_block bb)
360{
361  return single_pred_edge (bb)->src;
362}
363 
364/* Iterator object for edges.  */
365 
366struct edge_iterator {
367  unsigned index;
368  vec<edge, va_gc> **container;
369};
370 
371inline vec<edge, va_gc> *
372ei_container (edge_iterator i)
373{
374  gcc_checking_assert (i.container)((void)(!(i.container) ? fancy_abort ("/buildworker/marxinbox-gcc-clang-static-analyzer/build/gcc/basic-block.h"
, 374, __FUNCTION__), 0 : 0));
375  return *i.container;
376}
377 
378#define ei_start(iter)ei_start_1 (&(iter)) ei_start_1 (&(iter))
379#define ei_last(iter)ei_last_1 (&(iter)) ei_last_1 (&(iter))
380 
381/* Return an iterator pointing to the start of an edge vector.  */
382inline edge_iterator
383ei_start_1 (vec<edge, va_gc> **ev)
384{
385  edge_iterator i;
386 
387  i.index = 0;
388  i.container = ev;
389 
390  return i;
391}
392 
393/* Return an iterator pointing to the last element of an edge
394   vector.  */
395inline edge_iterator
396ei_last_1 (vec<edge, va_gc> **ev)
397{
398  edge_iterator i;
399 
400  i.index = EDGE_COUNT (*ev)vec_safe_length (*ev) - 1;
401  i.container = ev;
402 
403  return i;
404}
405 
406/* Is the iterator `i' at the end of the sequence?  */
407inline bool
408ei_end_p (edge_iterator i)
409{
410  return (i.index == EDGE_COUNT (ei_container (i))vec_safe_length (ei_container (i)));
411}
412 
413/* Is the iterator `i' at one position before the end of the
414   sequence?  */
415inline bool
416ei_one_before_end_p (edge_iterator i)
417{
418  return (i.index + 1 == EDGE_COUNT (ei_container (i))vec_safe_length (ei_container (i)));
419}
420 
421/* Advance the iterator to the next element.  */
422inline void
423ei_next (edge_iterator *i)
424{
425  gcc_checking_assert (i->index < EDGE_COUNT (ei_container (*i)))((void)(!(i->index < vec_safe_length (ei_container (*i)
)) ? fancy_abort ("/buildworker/marxinbox-gcc-clang-static-analyzer/build/gcc/basic-block.h"
, 425, __FUNCTION__), 0 : 0));
426  i->index++;
427}
428 
429/* Move the iterator to the previous element.  */
430inline void
431ei_prev (edge_iterator *i)
432{
433  gcc_checking_assert (i->index > 0)((void)(!(i->index > 0) ? fancy_abort ("/buildworker/marxinbox-gcc-clang-static-analyzer/build/gcc/basic-block.h"
, 433, __FUNCTION__), 0 : 0));
434  i->index--;
435}
436 
437/* Return the edge pointed to by the iterator `i'.  */
438inline edge
439ei_edge (edge_iterator i)
440{
441  return EDGE_I (ei_container (i), i.index)(*ei_container (i))[(i.index)];
442}
443 
444/* Return an edge pointed to by the iterator.  Do it safely so that
445   NULL is returned when the iterator is pointing at the end of the
446   sequence.  */
447inline edge
448ei_safe_edge (edge_iterator i)
449{
450  return !ei_end_p (i) ? ei_edge (i) : NULLnullptr;
451}
452 
453/* Return 1 if we should continue to iterate.  Return 0 otherwise.
454   *Edge P is set to the next edge if we are to continue to iterate
455   and NULL otherwise.  */
456 
457inline bool
458ei_cond (edge_iterator ei, edge *p)
459{
460  if (!ei_end_p (ei))
13
←
Taking false branch→
461    {
462      *p = ei_edge (ei);
463      return 1;
464    }
465  else
466    {
467      *p = NULLnullptr;
14
←
Null pointer value stored to 'other_e'→
468      return 0;
469    }
470}
471 
472/* This macro serves as a convenient way to iterate each edge in a
473   vector of predecessor or successor edges.  It must not be used when
474   an element might be removed during the traversal, otherwise
475   elements will be missed.  Instead, use a for-loop like that shown
476   in the following pseudo-code:
477 
478   FOR (ei = ei_start (bb->succs); (e = ei_safe_edge (ei)); )
479     {
480	IF (e != taken_edge)
481	  remove_edge (e);
482	ELSE
483	  ei_next (&ei);
484     }
485*/
486 
487#define FOR_EACH_EDGE(EDGE,ITER,EDGE_VEC)for ((ITER) = ei_start_1 (&((EDGE_VEC))); ei_cond ((ITER)
, &(EDGE)); ei_next (&(ITER)))	\
488  for ((ITER) = ei_start ((EDGE_VEC))ei_start_1 (&((EDGE_VEC)));		\
489       ei_cond ((ITER), &(EDGE));		\
490       ei_next (&(ITER)))
491 
492#define CLEANUP_EXPENSIVE1	1	/* Do relatively expensive optimizations
493					   except for edge forwarding */
494#define CLEANUP_CROSSJUMP2	2	/* Do crossjumping.  */
495#define CLEANUP_POST_REGSTACK4	4	/* We run after reg-stack and need
496					   to care REG_DEAD notes.  */
497#define CLEANUP_THREADING8	8	/* Do jump threading.  */
498#define CLEANUP_NO_INSN_DEL16	16	/* Do not try to delete trivially dead
499					   insns.  */
500#define CLEANUP_CFGLAYOUT32	32	/* Do cleanup in cfglayout mode.  */
501#define CLEANUP_CFG_CHANGED64	64      /* The caller changed the CFG.  */
502#define CLEANUP_NO_PARTITIONING128	128     /* Do not try to fix partitions.  */
503#define CLEANUP_FORCE_FAST_DCE0x100	0x100	/* Force run_fast_dce to be called
504					   at least once.  */
505 
506/* Return true if BB is in a transaction.  */
507 
508inline bool
509bb_in_transaction (basic_block bb)
510{
511  return bb->flags & BB_IN_TRANSACTION;
512}
513 
514/* Return true when one of the predecessor edges of BB is marked with EDGE_EH.  */
515inline bool
516bb_has_eh_pred (basic_block bb)
517{
518  edge e;
519  edge_iterator ei;
520 
521  FOR_EACH_EDGE (e, ei, bb->preds)for ((ei) = ei_start_1 (&((bb->preds))); ei_cond ((ei)
, &(e)); ei_next (&(ei)))
522    {
523      if (e->flags & EDGE_EH)
524	return true;
525    }
526  return false;
527}
528 
529/* Return true when one of the predecessor edges of BB is marked with EDGE_ABNORMAL.  */
530inline bool
531bb_has_abnormal_pred (basic_block bb)
532{
533  edge e;
534  edge_iterator ei;
535 
536  FOR_EACH_EDGE (e, ei, bb->preds)for ((ei) = ei_start_1 (&((bb->preds))); ei_cond ((ei)
, &(e)); ei_next (&(ei)))
537    {
538      if (e->flags & EDGE_ABNORMAL)
539	return true;
540    }
541  return false;
542}
543 
544/* Return the fallthru edge in EDGES if it exists, NULL otherwise.  */
545inline edge
546find_fallthru_edge (vec<edge, va_gc> *edges)
547{
548  edge e;
549  edge_iterator ei;
550 
551  FOR_EACH_EDGE (e, ei, edges)for ((ei) = ei_start_1 (&((edges))); ei_cond ((ei), &
(e)); ei_next (&(ei)))
552    if (e->flags & EDGE_FALLTHRU)
553      break;
554 
555  return e;
556}
557 
558/* Check tha probability is sane.  */
559 
560inline void
561check_probability (int prob)
562{
563  gcc_checking_assert (prob >= 0 && prob <= REG_BR_PROB_BASE)((void)(!(prob >= 0 && prob <= 10000) ? fancy_abort
 ("/buildworker/marxinbox-gcc-clang-static-analyzer/build/gcc/basic-block.h"
, 563, __FUNCTION__), 0 : 0));
564}
565 
566/* Given PROB1 and PROB2, return PROB1*PROB2/REG_BR_PROB_BASE. 
567   Used to combine BB probabilities.  */
568 
569inline int
570combine_probabilities (int prob1, int prob2)
571{
572  check_probability (prob1);
573  check_probability (prob2);
574  return RDIV (prob1 * prob2, REG_BR_PROB_BASE)(((prob1 * prob2) + (10000) / 2) / (10000));
575}
576 
577/* Apply scale factor SCALE on frequency or count FREQ. Use this
578   interface when potentially scaling up, so that SCALE is not
579   constrained to be < REG_BR_PROB_BASE.  */
580 
581inline gcov_type
582apply_scale (gcov_type freq, gcov_type scale)
583{
584  return RDIV (freq * scale, REG_BR_PROB_BASE)(((freq * scale) + (10000) / 2) / (10000));
585}
586 
587/* Apply probability PROB on frequency or count FREQ.  */
588 
589inline gcov_type
590apply_probability (gcov_type freq, int prob)
591{
592  check_probability (prob);
593  return apply_scale (freq, prob);
594}
595 
596/* Return inverse probability for PROB.  */
597 
598inline int
599inverse_probability (int prob1)
600{
601  check_probability (prob1);
602  return REG_BR_PROB_BASE10000 - prob1;
603}
604 
605/* Return true if BB has at least one abnormal outgoing edge.  */
606 
607inline bool
608has_abnormal_or_eh_outgoing_edge_p (basic_block bb)
609{
610  edge e;
611  edge_iterator ei;
612 
613  FOR_EACH_EDGE (e, ei, bb->succs)for ((ei) = ei_start_1 (&((bb->succs))); ei_cond ((ei)
, &(e)); ei_next (&(ei)))
614    if (e->flags & (EDGE_ABNORMAL | EDGE_EH))
615      return true;
616 
617  return false;
618}
619 
620/* Return true when one of the predecessor edges of BB is marked with
621   EDGE_ABNORMAL_CALL or EDGE_EH.  */
622 
623inline bool
624has_abnormal_call_or_eh_pred_edge_p (basic_block bb)
625{
626  edge e;
627  edge_iterator ei;
628 
629  FOR_EACH_EDGE (e, ei, bb->preds)for ((ei) = ei_start_1 (&((bb->preds))); ei_cond ((ei)
, &(e)); ei_next (&(ei)))
630    if (e->flags & (EDGE_ABNORMAL_CALL | EDGE_EH))
631      return true;
632 
633  return false;
634}
635 
636/* Return count of edge E.  */
637inline profile_count edge_def::count () const
638{
639  return src->count.apply_probability (probability);
640}
641 
642#endif /* GCC_BASIC_BLOCK_H */