[FFmpeg-devel] [PATCH] h264_i386: Optimize decode_significance_8x8_x86 for 64 bit.

Reimar Döffinger Reimar.Doeffinger at gmx.de
Mon Nov 17 08:19:32 CET 2014

On 17.11.2014, at 02:37, Michael Niedermayer <michaelni at gmx.at> wrote:
> On Sat, Nov 15, 2014 at 06:16:03PM +0100, Reimar Döffinger wrote:
>> 11674 -> 10877 decicycles on my Phenom II.
>> Overall speedup was unfortunately within measurement error.
> here its  10153 ->10135

I suspect it also depends a bit on the compiler and how it changes the surrounding code.
Note that I also tested with PIC actually.

> but ive a slightly odd feeling about the chnages to the asm code,
> iam not sure if all assemblers will be happy about the changed
> code

Do you mean particularly the movzbl change?
I am also unsure about that, I think there was a reason for that %k6 mess...
But this as well as movzx seemed to work for me...

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