This patch fixes a profiledbootstrap failure that occurred after I
added some profile fixup. The initial profile insanity occurred
upstream of my change, but my change caused the insanity to spread to
the edge probability, resulting in a verify failure. The patch below
ensures this doesn't occur.
Bootstrapped and tested on x86-64-unknown-linux-gnu. A
profiledbootstrap build also now succeeds. Ok for trunk?
Thanks,
Teresa
2013-10-29 Teresa Johnson <tejohn...@google.com>
PR ipa/58862
* tree-ssa-tail-merge.c (replace_block_by): Tolerate profile
insanities when updating probabilities.
Index: tree-ssa-tail-merge.c
===================================================================
--- tree-ssa-tail-merge.c (revision 204166)
+++ tree-ssa-tail-merge.c (working copy)
@@ -1467,7 +1467,7 @@ static void
replace_block_by (basic_block bb1, basic_block bb2)
{
edge pred_edge;
- edge e1;
+ edge e1, e2;
edge_iterator ei;
unsigned int i;
gimple bb2_phi;
@@ -1502,16 +1502,22 @@ replace_block_by (basic_block bb1, basic_block bb2
bb2->count += bb1->count;
/* Merge the outgoing edge counts from bb1 onto bb2. */
+ gcov_type out_sum = 0;
FOR_EACH_EDGE (e1, ei, bb1->succs)
{
- edge e2;
e2 = find_edge (bb2, e1->dest);
gcc_assert (e2);
e2->count += e1->count;
- /* Recompute the probability from the new merged edge count (bb2->count
- was updated above). */
- e2->probability = GCOV_COMPUTE_SCALE (e2->count, bb2->count);
+ out_sum += e2->count;
}
+ /* Recompute the edge probabilities from the new merged edge count.
+ Use the sum of the new merged edge counts computed above instead
+ of bb2's merged count, in case there are profile count insanities
+ making the bb count inconsistent with the edge weights. */
+ FOR_EACH_EDGE (e2, ei, bb2->succs)
+ {
+ e2->probability = GCOV_COMPUTE_SCALE (e2->count, out_sum);
+ }
/* Do updates that use bb1, before deleting bb1. */
release_last_vdef (bb1);
--
Teresa Johnson | Software Engineer | tejohn...@google.com | 408-460-2413
