[Bug target/61570] -march=native CPU you selected does not support x86-64 instruction under QEMU

["mikpelinux at gmail dot com" <gcc-bugzilla at gcc dot gnu dot org>]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=61570

Mikael Pettersson <mikpelinux at gmail dot com> changed:

           What    |Removed                     |Added
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                 CC|                            |mikpelinux at gmail dot com

--- Comment #3 from Mikael Pettersson <mikpelinux at gmail dot com> ---
(In reply to Jakub Jelinek from comment #2)
> Sure, but for this model AFAIK we go through the default: case of PENTIUMPRO
> anyway, where we only test the flags, so even if it used some completely
> unknown family number, it would still behave the same.
> So, can't we before:
>               else if (has_sse3)
>                 /* It is Core Duo.  */
>                 cpu = "pentium-m";
>               else if (has_sse2)
>                 /* It is Pentium M.  */
>                 cpu = "pentium-m";
> just add
>               else if (has_longmode)
>                 /* Some unknown 64-bit CPU, perhaps emulator?  */
>                 cpu = "x86-64";
> ?

That looks reasonable.

> Otherwise, QEMU, if it doesn't want to support SSSE3 and SSE3, and doesn't
> want to support 3dNOW either would need to identify itself as something
> other than Intel and AMD.

I don't recall if the 1st gen 64-bit Netburst had SSE3/SSSE3 or not, but if it
didn't then emulating that should be close enough to generic x86_64.  Otherwise
I'd prefer qemu to choose a unique vendor, unique family, or some high unused
model (e.g. all-bits-one).