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From: "pinskia at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
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Subject: [Bug target/85740] Non-optimal determining maximum in a loop
Date: Sat, 21 Aug 2021 20:19:33 +0000
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D85740

Andrew Pinski <pinskia at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
          Component|middle-end                  |target

--- Comment #11 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
So GCC heurstics for figuring out a[i] > m if it is likely or unlikely is
always going to be "wrong". My bet if the test vector was always incrementi=
ng,
the version without the __builtin_expect would be faster.

x86_64 has a loop cache which is why the version without the __builtin_expe=
ct
seems faster.=