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From: "lukas.graetz@tu-darmstadt.de" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug ipa/111643] __attribute__((flatten)) with -O1 runs out of
 memory (killed cc1)
Date: Fri, 06 Oct 2023 22:03:10 +0000
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D111643

--- Comment #14 from Lukas Gr=C3=A4tz <lukas.graetz@tu-darmstadt.de> ---

(In reply to Andrew Pinski from comment #13)
> (In reply to Andrew Pinski from comment #12)
> > Gcc does have tail call optimization which should allow the instrumenta=
tion
> > with less overhead. Though tail call optimization happens at -O2 and ab=
ove
> > only (by default).
>=20
> The only improvement to this would be fall through alias which allows the
> removal of the jump to the other function. A direct non-conditional jump =
is
> usually predictable so the overhead should be small still.

Thanks! I thought that there was still some stack involved also causing some
overhead for every function call (in comparison to a pure non-conditional
jump). When I have time next week, I will try to look into that in detail.=