[MPlayer-cvslog] r35673 - trunk/libmpcodecs/vf_ass.c

[Reimar Döffinger]

Xidorn Quan <quanxunzhen at gmail.com> wrote:

>On Thu, Dec 13, 2012 at 3:42 PM, Reimar Döffinger
><Reimar.Doeffinger at gmx.de> wrote:
>>
>>
>> On 13 Dec 2012, at 03:17, upsuper <subversion at mplayerhq.hu> wrote:
>>
>>> Author: upsuper
>>> Date: Thu Dec 13 03:17:27 2012
>>> New Revision: 35673
>>>
>>> Log:
>>> Reduce register usage to fix the compilation in x86.
>>
>> That reduces the registers used to 6 (assuming the compiler figures
>it out).
>> So it still will not compile if both ebx and ebp are unavailable
>(debug build with PIC for example. Note that e.g. Gentoo hardened
>compilers will force PIC even for binaries, not just shared objects).
>
>Another asm block in render_frame_420p_sse4 also uses 6 registers,
>so that should be modified as well soon. I will try to reduce the
>usage further, but I wonder whether it is a good idea to temporarily
>disable this optimization first for 32bit system.

IMHO disabling on 32 bit is overkill.
As is optimizing it to work with only 5 registers, that should only ever happen in debug builds, at least if it is a non-trivial effort.
Just change the #if to check that on 32 bit either ebx or ebp is available.
libavutil might even have a helper macro for that.