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From: "rguenth at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
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Subject: [Bug tree-optimization/104475] [12 Regression] Wstringop-overflow +
 atomics incorrect warning on dynamic object
Date: Wed, 23 Mar 2022 12:47:39 +0000
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D104475

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

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

--- Comment #9 from Richard Biener <rguenth at gcc dot gnu.org> ---
I think threading unlikely paths is never worth it and usually NULL pointer
checks are statically predicted.

I guess one idea would be to scale BB cost based on entry_BB->count vs.
BB->count so we more quickly run into the threading size limit for unlikely
executed blocks?  Likewise since we first evaluate all threading opportunit=
ies
in a function (do we?) we should sort them so we first thread the "best" one
and use a global threading limit instead one applied to each individual path
(so we'd just stop threading once we hit the limit).

Can we, for GCC 12, at least stop threading !maybe_hot_edge_p()?  Eventually
we can produce sth like a maybe_hot_threading_path_p () taking into account
the whole path.=