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From: "piliu at redhat dot com" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug c/105134] tree-vectorize produces error code
Date: Wed, 30 Nov 2022 03:32:50 +0000
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D105134

--- Comment #10 from piliu at redhat dot com ---
(In reply to Andrew Pinski from comment #7)
> I am trying to understand this. Is it ok to use the SSE registers inside
> purgatory or not?
>=20

SSE can speed up the program, and if possible it is suggested to turn on.

Any guideline about when it can not be used?

> Now that the vectorizer is used turned on at -O2 and above, without
> -mno-sse, on x86_64 target, the vector instructions are generated. and si=
nce
> this is inside a tiny bootloader, I am suspecting you can't use SSE
> instructions here.
>=20

What is broken by SSE? That can be more persuaded.

Thanks,

Pingfan=