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[Bug tree-optimization/61607] DOM missed jump threading and destroyed loops
- From: "law at redhat dot com" <gcc-bugzilla at gcc dot gnu dot org>
- To: gcc-bugs at gcc dot gnu dot org
- Date: Fri, 27 Jun 2014 16:20:24 +0000
- Subject: [Bug tree-optimization/61607] DOM missed jump threading and destroyed loops
- Auto-submitted: auto-generated
- References: <bug-61607-4 at http dot gcc dot gnu dot org/bugzilla/>
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=61607
--- Comment #8 from Jeffrey A. Law <law at redhat dot com> ---
FWIW, I vaguely recall experimenting with following the SSA_NAME_VALUE chains
in the past and having problems with cycles. IIRC we can get cycles from
things like recording equivalences created by equality tests.
We could put a (small) upper limit on the number of SSA_NAME_VALUEs we walk.
I'd expect the vast majority of the time we'd be walking just one node. I
guess that's worth investigating.