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From: "wilco at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
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Subject: [Bug target/91598] [8/9 regression] 60% speed drop on neon intrinsic
 loop
Date: Mon, 11 Jan 2021 20:35:07 +0000
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D91598

Wilco <wilco at gcc dot gnu.org> changed:

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

--- Comment #7 from Wilco <wilco at gcc dot gnu.org> ---
Fixed in GCC9 and trunk. Given the regression is so large, it is worth
backporting.

The other issue is that assembler statements (and likely any RTL instruction
without specified latencies) are badly scheduled. Honoring all known latenc=
ies
and assuming a reasonable default latency otherwise would be a better appro=
ach.=