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From: "wdijkstr at arm dot com" <sourceware-bugzilla@sourceware.org>
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Subject: [Bug math/27461] Unixbench/whetstone-double performance regression
 on glibc2.32
Date: Wed, 24 Feb 2021 10:49:55 +0000
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https://sourceware.org/bugzilla/show_bug.cgi?id=3D27461

--- Comment #3 from Wilco <wdijkstr at arm dot com> ---
(In reply to Siddhesh Poyarekar from comment #1)
> ISTM that the core assumption when we merged _finite with regular functio=
ns
> was that the overhead of error checking was negligible, but that's clearly
> not true for the whetstone benchmark.

It's the opposite, using a separate veneer for error checks is expensive as
this benchmark shows. So with -Ofast you might see a regression on functions
that were special cased in math-finite.h.

So what needs to happen is removal of these veneers so that math functions =
are
always directly called and do their own error checks.

--=20
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