[FFmpeg-devel] [PATCH] read_time() for SPARC

[Måns Rullgård]

Michael Kostylev <michael.kostylev at gmail.com> writes:

> On Fri Sep 10 08:59:27 2010
> M?ns Rullg?rd wrote:
>
>>>>> if the only issue left is the sometimes unneeded stx instruction
>>>>> then i approve the patch with this. If there are other issues they
>>>>> of course have to be fixed first
>>>>
>>>>Apparently the ifdef test in the patch is not reliable.
>>>
>>> Redone.
>>>
>>> Michael
>>>
>>> +#ifndef AVUTIL_SPARC_TIMER_H
>>> +#define AVUTIL_SPARC_TIMER_H
>>> +
>>> +#if defined(__arch64__) || defined(__sparc_v9__)
>>
>>I'm still not convinced this is right:
>
> There is an issue with -m32 on Solaris.

I don't understand.

>>$ sparc-unknown-linux-gnu-gcc -m32 -mcpu=v9 -mno-v8plus -dM -E -xc /dev/null | grep -E 'arch|sparc'
>>#define sparc 1
>>#define __sparc__ 1
>>#define __sparc 1
>>#define __sparc_v9__ 1
>
> This is as right as xor rax,rax in an i386 binary built with -march=core2.

Yes, that instruction would be invalid there.  In a pure 32-bit
environment, you can't use the high half of 64-bit registers, even if
they are physically present.  Consider what happens on a context switch.

-- 
M?ns Rullg?rd
mans at mansr.com