The jump threading handling in the case of a joiner block was not updating
profile information (it was being updated in the non-joiner case). Added
profile updates for the joiner case, in one place by commoning the
handling between the joiner and non-joiner cases.
Bootstrapped and tested on x86_64-unknown-linux-gnu. Ok for trunk?
Thanks,
Teresa
2013-09-30 Teresa Johnson <tejohn...@google.com>
* tree-ssa-threadupdate.c (ssa_fix_duplicate_block_edges):
Update redirected out edge count in joiner case.
(ssa_redirect_edges): Common the joiner and non-joiner cases
so that joiner case gets profile updates.
* testsuite/gcc.dg/tree-ssa/ssa-dom-thread-3.c (expand_one_var):
Update for additional dump message.
Index: tree-ssa-threadupdate.c
===================================================================
--- tree-ssa-threadupdate.c (revision 202947)
+++ tree-ssa-threadupdate.c (working copy)
@@ -403,6 +403,7 @@ ssa_fix_duplicate_block_edges (struct redirection_
threading through. That's the edge we want to redirect. */
victim = find_edge (rd->dup_block, THREAD_TARGET (e)->dest);
e2 = redirect_edge_and_branch (victim, THREAD_TARGET2 (e)->dest);
+ e2->count = THREAD_TARGET2 (e)->count;
/* If we redirected the edge, then we need to copy PHI arguments
at the target. If the edge already existed (e2 != victim case),
@@ -497,18 +498,8 @@ ssa_redirect_edges (struct redirection_data **slot
free (el);
thread_stats.num_threaded_edges++;
- /* If we are threading through a joiner block, then we have to
- find the edge we want to redirect and update some PHI nodes. */
- if (THREAD_TARGET2 (e))
- {
- edge e2;
- /* We want to redirect the incoming edge to the joiner block (E)
- to instead reach the duplicate of the joiner block. */
- e2 = redirect_edge_and_branch (e, rd->dup_block);
- flush_pending_stmts (e2);
- }
- else if (rd->dup_block)
+ if (rd->dup_block)
{
edge e2;
@@ -522,9 +513,15 @@ ssa_redirect_edges (struct redirection_data **slot
the computation overflows. */
if (rd->dup_block->frequency < BB_FREQ_MAX * 2)
rd->dup_block->frequency += EDGE_FREQUENCY (e);
- EDGE_SUCC (rd->dup_block, 0)->count += e->count;
- /* Redirect the incoming edge to the appropriate duplicate
- block. */
+
+ /* In the case of threading through a joiner block, the outgoing
+ edges from the duplicate block were updated when they were
+ redirected during ssa_fix_duplicate_block_edges. */
+ if (!THREAD_TARGET2 (e))
+ EDGE_SUCC (rd->dup_block, 0)->count += e->count;
+
+ /* Redirect the incoming edge (possibly to the joiner block) to the
+ appropriate duplicate block. */
e2 = redirect_edge_and_branch (e, rd->dup_block);
gcc_assert (e == e2);
flush_pending_stmts (e2);
Index: testsuite/gcc.dg/tree-ssa/ssa-dom-thread-3.c
===================================================================
--- testsuite/gcc.dg/tree-ssa/ssa-dom-thread-3.c (revision 202947)
+++ testsuite/gcc.dg/tree-ssa/ssa-dom-thread-3.c (working copy)
@@ -42,7 +42,7 @@ expand_one_var (tree var, unsigned char toplevel,
abort ();
}
/* We should thread the jump, through an intermediate block. */
-/* { dg-final { scan-tree-dump-times "Threaded" 1 "dom1"} } */
+/* { dg-final { scan-tree-dump-times "Threaded" 2 "dom1"} } */
/* { dg-final { scan-tree-dump-times "Registering jump thread:
\\(.*\\) incoming edge; \\(.*\\) joiner; \\(.*\\) nocopy;" 1 "dom1"}
} */
/* { dg-final { cleanup-tree-dump "dom1" } } */
--
Teresa Johnson | Software Engineer | tejohn...@google.com | 408-460-2413
