[Bug rtl-optimization/68435] [6 Regression] Missed if-conversion optimization

[ktkachov at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=68435

--- Comment #8 from ktkachov at gcc dot gnu.org ---
(In reply to Yuri Rumyantsev from comment #6)
> It turned out that fresh gcc performs tail duplication (aka path splitting)
> preventing if-conversion. So I post a dump for 20150929 compiler which
> reproduces the issue.

Yes, I noticed that as well.
There is an issue in ifcvt.c as well that's exposed for commits before r230364.
The fix for the ifcvt is simple enough and I'm testing it at the moment.