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[Bug tree-optimization/82187] missed PRE at -O3
- From: "rguenth at gcc dot gnu.org" <gcc-bugzilla at gcc dot gnu dot org>
- To: gcc-bugs at gcc dot gnu dot org
- Date: Tue, 14 Nov 2017 15:18:42 +0000
- Subject: [Bug tree-optimization/82187] missed PRE at -O3
- Auto-submitted: auto-generated
- References: <bug-82187-4@http.gcc.gnu.org/bugzilla/>
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=82187
--- Comment #2 from Richard Biener <rguenth at gcc dot gnu.org> ---
PRE thinks we are creating a loop-carried dependence that might prevent
vectorization (which is enabled at -O3) thus it doesn't perform the transform.
So it's a feature ...