[FFmpeg-devel] [PATCH] dnxhd_mmx: prefer xmm registers below xmm6 when they are available

Ramiro Polla ramiro.polla
Sun Oct 31 19:34:04 CET 2010

On Sat, Oct 30, 2010 at 6:23 PM, Reimar D?ffinger
<Reimar.Doeffinger at gmx.de> wrote:
> On Sat, Oct 30, 2010 at 05:40:50PM -0200, Ramiro Polla wrote:
>> Instead of marking all xmm registers in the clobber list, some
>> functions can use registers below xmm6, which makes it no longer an
>> issue for win64. A few more patches like this one will follow.
> The reason for this is that at least some code just initialized
> xmm7 to 0 and reused that over multiple asm blocks.
> I guess there's not much point for it now anymore though.

I think in these cases it's because people are so used to having xmm7
as 0, that xmm7 was used even though other lower registers were

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