https://gcc.gnu.org/bugzilla/show_bug.cgi?id=68541
Bug ID: 68541
Summary: [6 Regression] Path splitting causes if-conversion
miss
Product: gcc
Version: 6.0
Status: UNCONFIRMED
Keywords: missed-optimization
Severity: normal
Priority: P3
Component: tree-optimization
Assignee: unassigned at gcc dot gnu.org
Reporter: afomin.mailbox at gmail dot com
CC: izamyatin at gmail dot com, law at redhat dot com,
ysrumyan at gmail dot com
Target Milestone: ---
Target: i686-*-*
Created attachment 36835
--> https://gcc.gnu.org/bugzilla/attachment.cgi?id=36835&action=edit
A reproducer
Due to path splitting on SSA trees introduced in r230364, we miss an
if-conversion opportunity for (cond ? s++ : s--) expressions.
As for now (r230865), when compiling the attached testcase with -O2, after RTL
ce1 pass we have
3 possible IF blocks searched.
1 IF blocks converted.
2 true changes made.
while compiling it with -O2 -fno-split-paths results in
1 possible IF blocks searched.
0 IF blocks converted.
0 true changes made.
