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From: "rguenth at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug tree-optimization/114061] GCC fails vectorization when using
 __builtin_prefetch
Date: Fri, 23 Feb 2024 07:01:16 +0000
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D114061

Richard Biener <rguenth at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |rguenth at gcc dot gnu.org

--- Comment #5 from Richard Biener <rguenth at gcc dot gnu.org> ---
I think we could try to "vectorize" them by only updating the address (the
builtin doesn't specify a size) when that evolves in the scalar loop, updat=
ing
the step with the chosen VF.

Dependence shouldn't be a concern here.

The main issue is a representational - how to handle this in data-ref and
dependence analysis (or whether to just "skip" them in the vectorizer).=