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From: "juzhe.zhong at rivai dot ai" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug middle-end/114109] x264 satd vectorization vs LLVM
Date: Mon, 26 Feb 2024 11:24:55 +0000
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D114109

--- Comment #3 from JuzheZhong <juzhe.zhong at rivai dot ai> ---
(In reply to Robin Dapp from comment #2)
> It is vectorized with a higher zvl, e.g. zvl512b, refer
> https://godbolt.org/z/vbfjYn5Kd.

OK. I see. But Clang generates many slide instruction which are expensive in
real hardware.

And also vluxei64 is also expensive.

I am not sure which is better. It should be tested on real RISC-V hardware =
to
evaluate their performance rather than simply tested on SPIKE/QEMU dynamic
instructions count.=