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From: "soap at gentoo dot org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug tree-optimization/94617] Simple if condition not optimized
Date: Thu, 16 Apr 2020 12:02:04 +0000
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D94617

--- Comment #2 from David Seifert <soap at gentoo dot org> ---
(In reply to Richard Biener from comment #1)
> Why do you think this is terrible?  Aggressive use of conditional moves is
> not
> a good idea in general.

I've benchmarked the code, and on a Zen 2 the GCC produced code is 1.8x slo=
wer
than the Clang code. My gut feeling is the jump instruction killing
performance. I haven't tried it on an older CPU, but I can give it a try th=
ere
too.=