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From: "belagod at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug tree-optimization/59651] [4.9 Regression] Vectorizer failing to spot dependence causes incorrect code generation.
Date: Wed, 01 Jan 2014 18:31:00 -0000
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http://gcc.gnu.org/bugzilla/show_bug.cgi?id=59651

--- Comment #4 from belagod at gcc dot gnu.org ---
Thanks for looking at this.

Just to clarify, do you mean loop versioning happens in the up-counting loop?
Because in the down-counting loop, a partition seems to be happening with 2
iterations of the loop getting vectorized and the remaining 2 are left scalar.