[FFmpeg-devel] [PATCH] x86: use raw opcode for xgetbv instruction

Luca Barbato lu_zero
Sun Feb 20 17:16:16 CET 2011


On 02/20/2011 04:43 PM, M?ns Rullg?rd wrote:
> Luca Barbato <lu_zero at gentoo.org> writes:
> 
>> On 02/20/2011 03:39 PM, Mans Rullgard wrote:
>>> This allows the CPU detection to work with assemblers not supporting
>>> the xgetbv mnemonic.  These include clang and some BSD versions.
>>>
>>> All AVX code will be written for yasm, where the main assembler
>>> is not involved.
>>
>> We'd better put a notice about this somewhere and/or prepare a configure
>> check in case somebody provides inline avx asm.
> 
> Note that xgetbv is not an avx instruction as such.  As for inline asm,
> we should discourage its use.

The notice should do. =)

-- 

Luca Barbato
Gentoo/linux
http://dev.gentoo.org/~lu_zero




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