This is the mail archive of the
gcc-bugs@gcc.gnu.org
mailing list for the GCC project.
[Bug tree-optimization/64992] More optimize opportunity
- From: "glisse at gcc dot gnu.org" <gcc-bugzilla at gcc dot gnu dot org>
- To: gcc-bugs at gcc dot gnu dot org
- Date: Mon, 16 Feb 2015 00:34:37 +0000
- Subject: [Bug tree-optimization/64992] More optimize opportunity
- Auto-submitted: auto-generated
- References: <bug-64992-4 at http dot gcc dot gnu dot org/bugzilla/>
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=64992
Marc Glisse <glisse at gcc dot gnu.org> changed:
What |Removed |Added
----------------------------------------------------------------------------
Status|WAITING |NEW
--- Comment #5 from Marc Glisse <glisse at gcc dot gnu.org> ---
We do not sink the code that computes d into the branch c==-1. If we did, the
second comparison would simplify to a constant. VRP is not clever enough to
"backport" new assertions to already computed values.
We could also simplify N*x==0 to x==0 even for unsigned when VRP information
tells us that overflow/wrap cannot happen (here N is 2 and x is in [0,1]).