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From: "wdijkstr at arm dot com" <sourceware-bugzilla@sourceware.org>
To: glibc-bugs@sourceware.org
Subject: [Bug libc/27437] [aarch64]memcpy_simd has performance regression
 with larger size on Neoverse N1
Date: Fri, 19 Feb 2021 13:12:24 +0000
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https://sourceware.org/bugzilla/show_bug.cgi?id=3D27437

--- Comment #7 from Wilco <wdijkstr at arm dot com> ---
(In reply to xuchunmei from comment #6)
> bench-memcpy-walk result show thar when length is larger than 1024,
> __memcpy_simd seems a little slower than __memcpy_generic.

Yes but the difference is small, and in bench-memcpy-large __memcpy_simd wi=
ns
by a huge margin on the unaligned cases.

Since none of these reproduce what you are seeing, would it be possible to
create a small testcase that demonstrates the issue you are seeing in
perf-bench-mem?

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