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Date: Sun, 28 May 2023 16:21:55 +0000
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D110007

Jan Hubicka <hubicka at gcc dot gnu.org> changed:

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

--- Comment #7 from Jan Hubicka <hubicka at gcc dot gnu.org> ---
Also note that branch predicted with 50% outcome is not necessarily
unpredictable for example in this:

for (int i =3D 0; i < 10000; i++)
  if (i&1)
     ....

I would expect branch predictor to work this out on modern systems.
So having explicit flag in branch_probability that given probability is hard
for CPU to predict would make sense and I was thinking we may try to get th=
is
info from auto-fdo eventually too.=