mirror of
https://git.FreeBSD.org/src.git
synced 2024-12-23 11:18:54 +00:00
891 lines
24 KiB
C
891 lines
24 KiB
C
/* Hooks for cfg representation specific functions.
|
|
Copyright (C) 2003, 2004, 2005 Free Software Foundation, Inc.
|
|
Contributed by Sebastian Pop <s.pop@laposte.net>
|
|
|
|
This file is part of GCC.
|
|
|
|
GCC is free software; you can redistribute it and/or modify
|
|
it under the terms of the GNU General Public License as published by
|
|
the Free Software Foundation; either version 2, or (at your option)
|
|
any later version.
|
|
|
|
GCC is distributed in the hope that it will be useful,
|
|
but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
|
GNU General Public License for more details.
|
|
|
|
You should have received a copy of the GNU General Public License
|
|
along with GCC; see the file COPYING. If not, write to
|
|
the Free Software Foundation, 51 Franklin Street, Fifth Floor,
|
|
Boston, MA 02110-1301, USA. */
|
|
|
|
#include "config.h"
|
|
#include "system.h"
|
|
#include "coretypes.h"
|
|
#include "tm.h"
|
|
#include "tree.h"
|
|
#include "rtl.h"
|
|
#include "basic-block.h"
|
|
#include "tree-flow.h"
|
|
#include "timevar.h"
|
|
#include "toplev.h"
|
|
|
|
/* A pointer to one of the hooks containers. */
|
|
static struct cfg_hooks *cfg_hooks;
|
|
|
|
/* Initialization of functions specific to the rtl IR. */
|
|
void
|
|
rtl_register_cfg_hooks (void)
|
|
{
|
|
cfg_hooks = &rtl_cfg_hooks;
|
|
}
|
|
|
|
/* Initialization of functions specific to the rtl IR. */
|
|
void
|
|
cfg_layout_rtl_register_cfg_hooks (void)
|
|
{
|
|
cfg_hooks = &cfg_layout_rtl_cfg_hooks;
|
|
}
|
|
|
|
/* Initialization of functions specific to the tree IR. */
|
|
|
|
void
|
|
tree_register_cfg_hooks (void)
|
|
{
|
|
cfg_hooks = &tree_cfg_hooks;
|
|
}
|
|
|
|
/* Returns current ir type (rtl = 0, trees = 1). */
|
|
|
|
int
|
|
ir_type (void)
|
|
{
|
|
return cfg_hooks == &tree_cfg_hooks ? 1 : 0;
|
|
}
|
|
|
|
/* Verify the CFG consistency.
|
|
|
|
Currently it does following: checks edge and basic block list correctness
|
|
and calls into IL dependent checking then. */
|
|
|
|
void
|
|
verify_flow_info (void)
|
|
{
|
|
size_t *edge_checksum;
|
|
int err = 0;
|
|
basic_block bb, last_bb_seen;
|
|
basic_block *last_visited;
|
|
|
|
timevar_push (TV_CFG_VERIFY);
|
|
last_visited = XCNEWVEC (basic_block, last_basic_block);
|
|
edge_checksum = XCNEWVEC (size_t, last_basic_block);
|
|
|
|
/* Check bb chain & numbers. */
|
|
last_bb_seen = ENTRY_BLOCK_PTR;
|
|
FOR_BB_BETWEEN (bb, ENTRY_BLOCK_PTR->next_bb, NULL, next_bb)
|
|
{
|
|
if (bb != EXIT_BLOCK_PTR
|
|
&& bb != BASIC_BLOCK (bb->index))
|
|
{
|
|
error ("bb %d on wrong place", bb->index);
|
|
err = 1;
|
|
}
|
|
|
|
if (bb->prev_bb != last_bb_seen)
|
|
{
|
|
error ("prev_bb of %d should be %d, not %d",
|
|
bb->index, last_bb_seen->index, bb->prev_bb->index);
|
|
err = 1;
|
|
}
|
|
|
|
last_bb_seen = bb;
|
|
}
|
|
|
|
/* Now check the basic blocks (boundaries etc.) */
|
|
FOR_EACH_BB_REVERSE (bb)
|
|
{
|
|
int n_fallthru = 0;
|
|
edge e;
|
|
edge_iterator ei;
|
|
|
|
if (bb->count < 0)
|
|
{
|
|
error ("verify_flow_info: Wrong count of block %i %i",
|
|
bb->index, (int)bb->count);
|
|
err = 1;
|
|
}
|
|
if (bb->frequency < 0)
|
|
{
|
|
error ("verify_flow_info: Wrong frequency of block %i %i",
|
|
bb->index, bb->frequency);
|
|
err = 1;
|
|
}
|
|
FOR_EACH_EDGE (e, ei, bb->succs)
|
|
{
|
|
if (last_visited [e->dest->index] == bb)
|
|
{
|
|
error ("verify_flow_info: Duplicate edge %i->%i",
|
|
e->src->index, e->dest->index);
|
|
err = 1;
|
|
}
|
|
if (e->probability < 0 || e->probability > REG_BR_PROB_BASE)
|
|
{
|
|
error ("verify_flow_info: Wrong probability of edge %i->%i %i",
|
|
e->src->index, e->dest->index, e->probability);
|
|
err = 1;
|
|
}
|
|
if (e->count < 0)
|
|
{
|
|
error ("verify_flow_info: Wrong count of edge %i->%i %i",
|
|
e->src->index, e->dest->index, (int)e->count);
|
|
err = 1;
|
|
}
|
|
|
|
last_visited [e->dest->index] = bb;
|
|
|
|
if (e->flags & EDGE_FALLTHRU)
|
|
n_fallthru++;
|
|
|
|
if (e->src != bb)
|
|
{
|
|
error ("verify_flow_info: Basic block %d succ edge is corrupted",
|
|
bb->index);
|
|
fprintf (stderr, "Predecessor: ");
|
|
dump_edge_info (stderr, e, 0);
|
|
fprintf (stderr, "\nSuccessor: ");
|
|
dump_edge_info (stderr, e, 1);
|
|
fprintf (stderr, "\n");
|
|
err = 1;
|
|
}
|
|
|
|
edge_checksum[e->dest->index] += (size_t) e;
|
|
}
|
|
if (n_fallthru > 1)
|
|
{
|
|
error ("wrong amount of branch edges after unconditional jump %i", bb->index);
|
|
err = 1;
|
|
}
|
|
|
|
FOR_EACH_EDGE (e, ei, bb->preds)
|
|
{
|
|
if (e->dest != bb)
|
|
{
|
|
error ("basic block %d pred edge is corrupted", bb->index);
|
|
fputs ("Predecessor: ", stderr);
|
|
dump_edge_info (stderr, e, 0);
|
|
fputs ("\nSuccessor: ", stderr);
|
|
dump_edge_info (stderr, e, 1);
|
|
fputc ('\n', stderr);
|
|
err = 1;
|
|
}
|
|
|
|
if (ei.index != e->dest_idx)
|
|
{
|
|
error ("basic block %d pred edge is corrupted", bb->index);
|
|
error ("its dest_idx should be %d, not %d",
|
|
ei.index, e->dest_idx);
|
|
fputs ("Predecessor: ", stderr);
|
|
dump_edge_info (stderr, e, 0);
|
|
fputs ("\nSuccessor: ", stderr);
|
|
dump_edge_info (stderr, e, 1);
|
|
fputc ('\n', stderr);
|
|
err = 1;
|
|
}
|
|
|
|
edge_checksum[e->dest->index] -= (size_t) e;
|
|
}
|
|
}
|
|
|
|
/* Complete edge checksumming for ENTRY and EXIT. */
|
|
{
|
|
edge e;
|
|
edge_iterator ei;
|
|
|
|
FOR_EACH_EDGE (e, ei, ENTRY_BLOCK_PTR->succs)
|
|
edge_checksum[e->dest->index] += (size_t) e;
|
|
|
|
FOR_EACH_EDGE (e, ei, EXIT_BLOCK_PTR->preds)
|
|
edge_checksum[e->dest->index] -= (size_t) e;
|
|
}
|
|
|
|
FOR_BB_BETWEEN (bb, ENTRY_BLOCK_PTR, NULL, next_bb)
|
|
if (edge_checksum[bb->index])
|
|
{
|
|
error ("basic block %i edge lists are corrupted", bb->index);
|
|
err = 1;
|
|
}
|
|
|
|
last_bb_seen = ENTRY_BLOCK_PTR;
|
|
|
|
/* Clean up. */
|
|
free (last_visited);
|
|
free (edge_checksum);
|
|
|
|
if (cfg_hooks->verify_flow_info)
|
|
err |= cfg_hooks->verify_flow_info ();
|
|
if (err)
|
|
internal_error ("verify_flow_info failed");
|
|
timevar_pop (TV_CFG_VERIFY);
|
|
}
|
|
|
|
/* Print out one basic block. This function takes care of the purely
|
|
graph related information. The cfg hook for the active representation
|
|
should dump representation-specific information. */
|
|
|
|
void
|
|
dump_bb (basic_block bb, FILE *outf, int indent)
|
|
{
|
|
edge e;
|
|
edge_iterator ei;
|
|
char *s_indent;
|
|
|
|
s_indent = alloca ((size_t) indent + 1);
|
|
memset (s_indent, ' ', (size_t) indent);
|
|
s_indent[indent] = '\0';
|
|
|
|
fprintf (outf, ";;%s basic block %d, loop depth %d, count ",
|
|
s_indent, bb->index, bb->loop_depth);
|
|
fprintf (outf, HOST_WIDEST_INT_PRINT_DEC, (HOST_WIDEST_INT) bb->count);
|
|
putc ('\n', outf);
|
|
|
|
fprintf (outf, ";;%s prev block ", s_indent);
|
|
if (bb->prev_bb)
|
|
fprintf (outf, "%d, ", bb->prev_bb->index);
|
|
else
|
|
fprintf (outf, "(nil), ");
|
|
fprintf (outf, "next block ");
|
|
if (bb->next_bb)
|
|
fprintf (outf, "%d", bb->next_bb->index);
|
|
else
|
|
fprintf (outf, "(nil)");
|
|
putc ('\n', outf);
|
|
|
|
fprintf (outf, ";;%s pred: ", s_indent);
|
|
FOR_EACH_EDGE (e, ei, bb->preds)
|
|
dump_edge_info (outf, e, 0);
|
|
putc ('\n', outf);
|
|
|
|
fprintf (outf, ";;%s succ: ", s_indent);
|
|
FOR_EACH_EDGE (e, ei, bb->succs)
|
|
dump_edge_info (outf, e, 1);
|
|
putc ('\n', outf);
|
|
|
|
if (cfg_hooks->dump_bb)
|
|
cfg_hooks->dump_bb (bb, outf, indent);
|
|
}
|
|
|
|
/* Redirect edge E to the given basic block DEST and update underlying program
|
|
representation. Returns edge representing redirected branch (that may not
|
|
be equivalent to E in the case of duplicate edges being removed) or NULL
|
|
if edge is not easily redirectable for whatever reason. */
|
|
|
|
edge
|
|
redirect_edge_and_branch (edge e, basic_block dest)
|
|
{
|
|
edge ret;
|
|
|
|
if (!cfg_hooks->redirect_edge_and_branch)
|
|
internal_error ("%s does not support redirect_edge_and_branch",
|
|
cfg_hooks->name);
|
|
|
|
ret = cfg_hooks->redirect_edge_and_branch (e, dest);
|
|
|
|
return ret;
|
|
}
|
|
|
|
/* Redirect the edge E to basic block DEST even if it requires creating
|
|
of a new basic block; then it returns the newly created basic block.
|
|
Aborts when redirection is impossible. */
|
|
|
|
basic_block
|
|
redirect_edge_and_branch_force (edge e, basic_block dest)
|
|
{
|
|
basic_block ret;
|
|
|
|
if (!cfg_hooks->redirect_edge_and_branch_force)
|
|
internal_error ("%s does not support redirect_edge_and_branch_force",
|
|
cfg_hooks->name);
|
|
|
|
ret = cfg_hooks->redirect_edge_and_branch_force (e, dest);
|
|
|
|
return ret;
|
|
}
|
|
|
|
/* Splits basic block BB after the specified instruction I (but at least after
|
|
the labels). If I is NULL, splits just after labels. The newly created edge
|
|
is returned. The new basic block is created just after the old one. */
|
|
|
|
edge
|
|
split_block (basic_block bb, void *i)
|
|
{
|
|
basic_block new_bb;
|
|
|
|
if (!cfg_hooks->split_block)
|
|
internal_error ("%s does not support split_block", cfg_hooks->name);
|
|
|
|
new_bb = cfg_hooks->split_block (bb, i);
|
|
if (!new_bb)
|
|
return NULL;
|
|
|
|
new_bb->count = bb->count;
|
|
new_bb->frequency = bb->frequency;
|
|
new_bb->loop_depth = bb->loop_depth;
|
|
|
|
if (dom_info_available_p (CDI_DOMINATORS))
|
|
{
|
|
redirect_immediate_dominators (CDI_DOMINATORS, bb, new_bb);
|
|
set_immediate_dominator (CDI_DOMINATORS, new_bb, bb);
|
|
}
|
|
|
|
return make_single_succ_edge (bb, new_bb, EDGE_FALLTHRU);
|
|
}
|
|
|
|
/* Splits block BB just after labels. The newly created edge is returned. */
|
|
|
|
edge
|
|
split_block_after_labels (basic_block bb)
|
|
{
|
|
return split_block (bb, NULL);
|
|
}
|
|
|
|
/* Moves block BB immediately after block AFTER. Returns false if the
|
|
movement was impossible. */
|
|
|
|
bool
|
|
move_block_after (basic_block bb, basic_block after)
|
|
{
|
|
bool ret;
|
|
|
|
if (!cfg_hooks->move_block_after)
|
|
internal_error ("%s does not support move_block_after", cfg_hooks->name);
|
|
|
|
ret = cfg_hooks->move_block_after (bb, after);
|
|
|
|
return ret;
|
|
}
|
|
|
|
/* Deletes the basic block BB. */
|
|
|
|
void
|
|
delete_basic_block (basic_block bb)
|
|
{
|
|
if (!cfg_hooks->delete_basic_block)
|
|
internal_error ("%s does not support delete_basic_block", cfg_hooks->name);
|
|
|
|
cfg_hooks->delete_basic_block (bb);
|
|
|
|
/* Remove the edges into and out of this block. Note that there may
|
|
indeed be edges in, if we are removing an unreachable loop. */
|
|
while (EDGE_COUNT (bb->preds) != 0)
|
|
remove_edge (EDGE_PRED (bb, 0));
|
|
while (EDGE_COUNT (bb->succs) != 0)
|
|
remove_edge (EDGE_SUCC (bb, 0));
|
|
|
|
if (dom_computed[CDI_DOMINATORS])
|
|
delete_from_dominance_info (CDI_DOMINATORS, bb);
|
|
if (dom_computed[CDI_POST_DOMINATORS])
|
|
delete_from_dominance_info (CDI_POST_DOMINATORS, bb);
|
|
|
|
/* Remove the basic block from the array. */
|
|
expunge_block (bb);
|
|
}
|
|
|
|
/* Splits edge E and returns the newly created basic block. */
|
|
|
|
basic_block
|
|
split_edge (edge e)
|
|
{
|
|
basic_block ret;
|
|
gcov_type count = e->count;
|
|
int freq = EDGE_FREQUENCY (e);
|
|
edge f;
|
|
bool irr = (e->flags & EDGE_IRREDUCIBLE_LOOP) != 0;
|
|
|
|
if (!cfg_hooks->split_edge)
|
|
internal_error ("%s does not support split_edge", cfg_hooks->name);
|
|
|
|
ret = cfg_hooks->split_edge (e);
|
|
ret->count = count;
|
|
ret->frequency = freq;
|
|
single_succ_edge (ret)->probability = REG_BR_PROB_BASE;
|
|
single_succ_edge (ret)->count = count;
|
|
|
|
if (irr)
|
|
{
|
|
ret->flags |= BB_IRREDUCIBLE_LOOP;
|
|
single_pred_edge (ret)->flags |= EDGE_IRREDUCIBLE_LOOP;
|
|
single_succ_edge (ret)->flags |= EDGE_IRREDUCIBLE_LOOP;
|
|
}
|
|
|
|
if (dom_computed[CDI_DOMINATORS])
|
|
set_immediate_dominator (CDI_DOMINATORS, ret, single_pred (ret));
|
|
|
|
if (dom_computed[CDI_DOMINATORS] >= DOM_NO_FAST_QUERY)
|
|
{
|
|
/* There are two cases:
|
|
|
|
If the immediate dominator of e->dest is not e->src, it
|
|
remains unchanged.
|
|
|
|
If immediate dominator of e->dest is e->src, it may become
|
|
ret, provided that all other predecessors of e->dest are
|
|
dominated by e->dest. */
|
|
|
|
if (get_immediate_dominator (CDI_DOMINATORS, single_succ (ret))
|
|
== single_pred (ret))
|
|
{
|
|
edge_iterator ei;
|
|
FOR_EACH_EDGE (f, ei, single_succ (ret)->preds)
|
|
{
|
|
if (f == single_succ_edge (ret))
|
|
continue;
|
|
|
|
if (!dominated_by_p (CDI_DOMINATORS, f->src,
|
|
single_succ (ret)))
|
|
break;
|
|
}
|
|
|
|
if (!f)
|
|
set_immediate_dominator (CDI_DOMINATORS, single_succ (ret), ret);
|
|
}
|
|
};
|
|
|
|
return ret;
|
|
}
|
|
|
|
/* Creates a new basic block just after the basic block AFTER.
|
|
HEAD and END are the first and the last statement belonging
|
|
to the block. If both are NULL, an empty block is created. */
|
|
|
|
basic_block
|
|
create_basic_block (void *head, void *end, basic_block after)
|
|
{
|
|
basic_block ret;
|
|
|
|
if (!cfg_hooks->create_basic_block)
|
|
internal_error ("%s does not support create_basic_block", cfg_hooks->name);
|
|
|
|
ret = cfg_hooks->create_basic_block (head, end, after);
|
|
|
|
if (dom_computed[CDI_DOMINATORS])
|
|
add_to_dominance_info (CDI_DOMINATORS, ret);
|
|
if (dom_computed[CDI_POST_DOMINATORS])
|
|
add_to_dominance_info (CDI_POST_DOMINATORS, ret);
|
|
|
|
return ret;
|
|
}
|
|
|
|
/* Creates an empty basic block just after basic block AFTER. */
|
|
|
|
basic_block
|
|
create_empty_bb (basic_block after)
|
|
{
|
|
return create_basic_block (NULL, NULL, after);
|
|
}
|
|
|
|
/* Checks whether we may merge blocks BB1 and BB2. */
|
|
|
|
bool
|
|
can_merge_blocks_p (basic_block bb1, basic_block bb2)
|
|
{
|
|
bool ret;
|
|
|
|
if (!cfg_hooks->can_merge_blocks_p)
|
|
internal_error ("%s does not support can_merge_blocks_p", cfg_hooks->name);
|
|
|
|
ret = cfg_hooks->can_merge_blocks_p (bb1, bb2);
|
|
|
|
return ret;
|
|
}
|
|
|
|
void
|
|
predict_edge (edge e, enum br_predictor predictor, int probability)
|
|
{
|
|
if (!cfg_hooks->predict_edge)
|
|
internal_error ("%s does not support predict_edge", cfg_hooks->name);
|
|
|
|
cfg_hooks->predict_edge (e, predictor, probability);
|
|
}
|
|
|
|
bool
|
|
predicted_by_p (basic_block bb, enum br_predictor predictor)
|
|
{
|
|
if (!cfg_hooks->predict_edge)
|
|
internal_error ("%s does not support predicted_by_p", cfg_hooks->name);
|
|
|
|
return cfg_hooks->predicted_by_p (bb, predictor);
|
|
}
|
|
|
|
/* Merges basic block B into basic block A. */
|
|
|
|
void
|
|
merge_blocks (basic_block a, basic_block b)
|
|
{
|
|
edge e;
|
|
edge_iterator ei;
|
|
|
|
if (!cfg_hooks->merge_blocks)
|
|
internal_error ("%s does not support merge_blocks", cfg_hooks->name);
|
|
|
|
cfg_hooks->merge_blocks (a, b);
|
|
|
|
/* Normally there should only be one successor of A and that is B, but
|
|
partway though the merge of blocks for conditional_execution we'll
|
|
be merging a TEST block with THEN and ELSE successors. Free the
|
|
whole lot of them and hope the caller knows what they're doing. */
|
|
|
|
while (EDGE_COUNT (a->succs) != 0)
|
|
remove_edge (EDGE_SUCC (a, 0));
|
|
|
|
/* Adjust the edges out of B for the new owner. */
|
|
FOR_EACH_EDGE (e, ei, b->succs)
|
|
e->src = a;
|
|
a->succs = b->succs;
|
|
a->flags |= b->flags;
|
|
|
|
/* B hasn't quite yet ceased to exist. Attempt to prevent mishap. */
|
|
b->preds = b->succs = NULL;
|
|
|
|
if (dom_computed[CDI_DOMINATORS])
|
|
redirect_immediate_dominators (CDI_DOMINATORS, b, a);
|
|
|
|
if (dom_computed[CDI_DOMINATORS])
|
|
delete_from_dominance_info (CDI_DOMINATORS, b);
|
|
if (dom_computed[CDI_POST_DOMINATORS])
|
|
delete_from_dominance_info (CDI_POST_DOMINATORS, b);
|
|
|
|
expunge_block (b);
|
|
}
|
|
|
|
/* Split BB into entry part and the rest (the rest is the newly created block).
|
|
Redirect those edges for that REDIRECT_EDGE_P returns true to the entry
|
|
part. Returns the edge connecting the entry part to the rest. */
|
|
|
|
edge
|
|
make_forwarder_block (basic_block bb, bool (*redirect_edge_p) (edge),
|
|
void (*new_bb_cbk) (basic_block))
|
|
{
|
|
edge e, fallthru;
|
|
edge_iterator ei;
|
|
basic_block dummy, jump;
|
|
|
|
if (!cfg_hooks->make_forwarder_block)
|
|
internal_error ("%s does not support make_forwarder_block",
|
|
cfg_hooks->name);
|
|
|
|
fallthru = split_block_after_labels (bb);
|
|
dummy = fallthru->src;
|
|
bb = fallthru->dest;
|
|
|
|
/* Redirect back edges we want to keep. */
|
|
for (ei = ei_start (dummy->preds); (e = ei_safe_edge (ei)); )
|
|
{
|
|
if (redirect_edge_p (e))
|
|
{
|
|
ei_next (&ei);
|
|
continue;
|
|
}
|
|
|
|
dummy->frequency -= EDGE_FREQUENCY (e);
|
|
dummy->count -= e->count;
|
|
if (dummy->frequency < 0)
|
|
dummy->frequency = 0;
|
|
if (dummy->count < 0)
|
|
dummy->count = 0;
|
|
fallthru->count -= e->count;
|
|
if (fallthru->count < 0)
|
|
fallthru->count = 0;
|
|
|
|
jump = redirect_edge_and_branch_force (e, bb);
|
|
if (jump)
|
|
new_bb_cbk (jump);
|
|
}
|
|
|
|
if (dom_info_available_p (CDI_DOMINATORS))
|
|
{
|
|
basic_block doms_to_fix[2];
|
|
|
|
doms_to_fix[0] = dummy;
|
|
doms_to_fix[1] = bb;
|
|
iterate_fix_dominators (CDI_DOMINATORS, doms_to_fix, 2);
|
|
}
|
|
|
|
cfg_hooks->make_forwarder_block (fallthru);
|
|
|
|
return fallthru;
|
|
}
|
|
|
|
void
|
|
tidy_fallthru_edge (edge e)
|
|
{
|
|
if (cfg_hooks->tidy_fallthru_edge)
|
|
cfg_hooks->tidy_fallthru_edge (e);
|
|
}
|
|
|
|
/* Fix up edges that now fall through, or rather should now fall through
|
|
but previously required a jump around now deleted blocks. Simplify
|
|
the search by only examining blocks numerically adjacent, since this
|
|
is how find_basic_blocks created them. */
|
|
|
|
void
|
|
tidy_fallthru_edges (void)
|
|
{
|
|
basic_block b, c;
|
|
|
|
if (!cfg_hooks->tidy_fallthru_edge)
|
|
return;
|
|
|
|
if (ENTRY_BLOCK_PTR->next_bb == EXIT_BLOCK_PTR)
|
|
return;
|
|
|
|
FOR_BB_BETWEEN (b, ENTRY_BLOCK_PTR->next_bb, EXIT_BLOCK_PTR->prev_bb, next_bb)
|
|
{
|
|
edge s;
|
|
|
|
c = b->next_bb;
|
|
|
|
/* We care about simple conditional or unconditional jumps with
|
|
a single successor.
|
|
|
|
If we had a conditional branch to the next instruction when
|
|
find_basic_blocks was called, then there will only be one
|
|
out edge for the block which ended with the conditional
|
|
branch (since we do not create duplicate edges).
|
|
|
|
Furthermore, the edge will be marked as a fallthru because we
|
|
merge the flags for the duplicate edges. So we do not want to
|
|
check that the edge is not a FALLTHRU edge. */
|
|
|
|
if (single_succ_p (b))
|
|
{
|
|
s = single_succ_edge (b);
|
|
if (! (s->flags & EDGE_COMPLEX)
|
|
&& s->dest == c
|
|
&& !find_reg_note (BB_END (b), REG_CROSSING_JUMP, NULL_RTX))
|
|
tidy_fallthru_edge (s);
|
|
}
|
|
}
|
|
}
|
|
|
|
/* Returns true if we can duplicate basic block BB. */
|
|
|
|
bool
|
|
can_duplicate_block_p (basic_block bb)
|
|
{
|
|
edge e;
|
|
|
|
if (!cfg_hooks->can_duplicate_block_p)
|
|
internal_error ("%s does not support can_duplicate_block_p",
|
|
cfg_hooks->name);
|
|
|
|
if (bb == EXIT_BLOCK_PTR || bb == ENTRY_BLOCK_PTR)
|
|
return false;
|
|
|
|
/* Duplicating fallthru block to exit would require adding a jump
|
|
and splitting the real last BB. */
|
|
e = find_edge (bb, EXIT_BLOCK_PTR);
|
|
if (e && (e->flags & EDGE_FALLTHRU))
|
|
return false;
|
|
|
|
return cfg_hooks->can_duplicate_block_p (bb);
|
|
}
|
|
|
|
/* Duplicates basic block BB and redirects edge E to it. Returns the
|
|
new basic block. The new basic block is placed after the basic block
|
|
AFTER. */
|
|
|
|
basic_block
|
|
duplicate_block (basic_block bb, edge e, basic_block after)
|
|
{
|
|
edge s, n;
|
|
basic_block new_bb;
|
|
gcov_type new_count = e ? e->count : 0;
|
|
edge_iterator ei;
|
|
|
|
if (!cfg_hooks->duplicate_block)
|
|
internal_error ("%s does not support duplicate_block",
|
|
cfg_hooks->name);
|
|
|
|
if (bb->count < new_count)
|
|
new_count = bb->count;
|
|
|
|
#ifdef ENABLE_CHECKING
|
|
gcc_assert (can_duplicate_block_p (bb));
|
|
#endif
|
|
|
|
new_bb = cfg_hooks->duplicate_block (bb);
|
|
if (after)
|
|
move_block_after (new_bb, after);
|
|
|
|
new_bb->loop_depth = bb->loop_depth;
|
|
new_bb->flags = bb->flags;
|
|
FOR_EACH_EDGE (s, ei, bb->succs)
|
|
{
|
|
/* Since we are creating edges from a new block to successors
|
|
of another block (which therefore are known to be disjoint), there
|
|
is no need to actually check for duplicated edges. */
|
|
n = unchecked_make_edge (new_bb, s->dest, s->flags);
|
|
n->probability = s->probability;
|
|
if (e && bb->count)
|
|
{
|
|
/* Take care for overflows! */
|
|
n->count = s->count * (new_count * 10000 / bb->count) / 10000;
|
|
s->count -= n->count;
|
|
}
|
|
else
|
|
n->count = s->count;
|
|
n->aux = s->aux;
|
|
}
|
|
|
|
if (e)
|
|
{
|
|
new_bb->count = new_count;
|
|
bb->count -= new_count;
|
|
|
|
new_bb->frequency = EDGE_FREQUENCY (e);
|
|
bb->frequency -= EDGE_FREQUENCY (e);
|
|
|
|
redirect_edge_and_branch_force (e, new_bb);
|
|
|
|
if (bb->count < 0)
|
|
bb->count = 0;
|
|
if (bb->frequency < 0)
|
|
bb->frequency = 0;
|
|
}
|
|
else
|
|
{
|
|
new_bb->count = bb->count;
|
|
new_bb->frequency = bb->frequency;
|
|
}
|
|
|
|
set_bb_original (new_bb, bb);
|
|
set_bb_copy (bb, new_bb);
|
|
|
|
return new_bb;
|
|
}
|
|
|
|
/* Return 1 if BB ends with a call, possibly followed by some
|
|
instructions that must stay with the call, 0 otherwise. */
|
|
|
|
bool
|
|
block_ends_with_call_p (basic_block bb)
|
|
{
|
|
if (!cfg_hooks->block_ends_with_call_p)
|
|
internal_error ("%s does not support block_ends_with_call_p", cfg_hooks->name);
|
|
|
|
return (cfg_hooks->block_ends_with_call_p) (bb);
|
|
}
|
|
|
|
/* Return 1 if BB ends with a conditional branch, 0 otherwise. */
|
|
|
|
bool
|
|
block_ends_with_condjump_p (basic_block bb)
|
|
{
|
|
if (!cfg_hooks->block_ends_with_condjump_p)
|
|
internal_error ("%s does not support block_ends_with_condjump_p",
|
|
cfg_hooks->name);
|
|
|
|
return (cfg_hooks->block_ends_with_condjump_p) (bb);
|
|
}
|
|
|
|
/* Add fake edges to the function exit for any non constant and non noreturn
|
|
calls, volatile inline assembly in the bitmap of blocks specified by
|
|
BLOCKS or to the whole CFG if BLOCKS is zero. Return the number of blocks
|
|
that were split.
|
|
|
|
The goal is to expose cases in which entering a basic block does not imply
|
|
that all subsequent instructions must be executed. */
|
|
|
|
int
|
|
flow_call_edges_add (sbitmap blocks)
|
|
{
|
|
if (!cfg_hooks->flow_call_edges_add)
|
|
internal_error ("%s does not support flow_call_edges_add",
|
|
cfg_hooks->name);
|
|
|
|
return (cfg_hooks->flow_call_edges_add) (blocks);
|
|
}
|
|
|
|
/* This function is called immediately after edge E is added to the
|
|
edge vector E->dest->preds. */
|
|
|
|
void
|
|
execute_on_growing_pred (edge e)
|
|
{
|
|
if (cfg_hooks->execute_on_growing_pred)
|
|
cfg_hooks->execute_on_growing_pred (e);
|
|
}
|
|
|
|
/* This function is called immediately before edge E is removed from
|
|
the edge vector E->dest->preds. */
|
|
|
|
void
|
|
execute_on_shrinking_pred (edge e)
|
|
{
|
|
if (cfg_hooks->execute_on_shrinking_pred)
|
|
cfg_hooks->execute_on_shrinking_pred (e);
|
|
}
|
|
|
|
/* This is used inside loop versioning when we want to insert
|
|
stmts/insns on the edges, which have a different behavior
|
|
in tree's and in RTL, so we made a CFG hook. */
|
|
void
|
|
lv_flush_pending_stmts (edge e)
|
|
{
|
|
if (cfg_hooks->flush_pending_stmts)
|
|
cfg_hooks->flush_pending_stmts (e);
|
|
}
|
|
|
|
/* Loop versioning uses the duplicate_loop_to_header_edge to create
|
|
a new version of the loop basic-blocks, the parameters here are
|
|
exactly the same as in duplicate_loop_to_header_edge or
|
|
tree_duplicate_loop_to_header_edge; while in tree-ssa there is
|
|
additional work to maintain ssa information that's why there is
|
|
a need to call the tree_duplicate_loop_to_header_edge rather
|
|
than duplicate_loop_to_header_edge when we are in tree mode. */
|
|
bool
|
|
cfg_hook_duplicate_loop_to_header_edge (struct loop *loop, edge e,
|
|
struct loops *loops, unsigned int ndupl,
|
|
sbitmap wont_exit, edge orig,
|
|
edge *to_remove,
|
|
unsigned int *n_to_remove, int flags)
|
|
{
|
|
gcc_assert (cfg_hooks->cfg_hook_duplicate_loop_to_header_edge);
|
|
return cfg_hooks->cfg_hook_duplicate_loop_to_header_edge (loop, e, loops,
|
|
ndupl, wont_exit,
|
|
orig, to_remove,
|
|
n_to_remove, flags);
|
|
}
|
|
|
|
/* Conditional jumps are represented differently in trees and RTL,
|
|
this hook takes a basic block that is known to have a cond jump
|
|
at its end and extracts the taken and not taken eges out of it
|
|
and store it in E1 and E2 respectively. */
|
|
void
|
|
extract_cond_bb_edges (basic_block b, edge *e1, edge *e2)
|
|
{
|
|
gcc_assert (cfg_hooks->extract_cond_bb_edges);
|
|
cfg_hooks->extract_cond_bb_edges (b, e1, e2);
|
|
}
|
|
|
|
/* Responsible for updating the ssa info (PHI nodes) on the
|
|
new condition basic block that guards the versioned loop. */
|
|
void
|
|
lv_adjust_loop_header_phi (basic_block first, basic_block second,
|
|
basic_block new, edge e)
|
|
{
|
|
if (cfg_hooks->lv_adjust_loop_header_phi)
|
|
cfg_hooks->lv_adjust_loop_header_phi (first, second, new, e);
|
|
}
|
|
|
|
/* Conditions in trees and RTL are different so we need
|
|
a different handling when we add the condition to the
|
|
versioning code. */
|
|
void
|
|
lv_add_condition_to_bb (basic_block first, basic_block second,
|
|
basic_block new, void *cond)
|
|
{
|
|
gcc_assert (cfg_hooks->lv_add_condition_to_bb);
|
|
cfg_hooks->lv_add_condition_to_bb (first, second, new, cond);
|
|
}
|