Re: [PATCH 2/2] xv: speed up YV12 -> NV12 conversion using SSE2 if available

[Sven Joachim <svenjoac-Mmb7MZpHnFY@public.gmane.org>]

On 2013-07-29 08:40 +0200, Ilia Mirkin wrote:

> memcpy() goes from taking 45% to 66% of total function time, which
> translates to a 30% decrease in NVPutImage runtime.
>
> Signed-off-by: Ilia Mirkin <imirkin-FrUbXkNCsVf2fBVCVOL8/A@public.gmane.org>
> ---
>  src/nouveau_xv.c | 33 ++++++++++++++++++++++++++-------
>  1 file changed, 26 insertions(+), 7 deletions(-)
>
> diff --git a/src/nouveau_xv.c b/src/nouveau_xv.c
> index 567e30c..5569b7c 100644
> --- a/src/nouveau_xv.c
> +++ b/src/nouveau_xv.c
> @@ -25,6 +25,8 @@
>  #include "config.h"
>  #endif
>  
> +#include <immintrin.h>
> +

Unfortunately, immintrin.h is not available on most architectures,
leading to build failures as can be seen on
https://buildd.debian.org/status/package.php?p=xserver-xorg-video-nouveau.

Any ideas?

>  #include "xf86xv.h"
>  #include <X11/extensions/Xv.h>
>  #include "exa.h"
> @@ -532,30 +534,47 @@ NVCopyNV12ColorPlanes(unsigned char *src1, unsigned char *src2,
>  
>  	w >>= 1;
>  	h >>= 1;
> +#ifdef __SSE2__
> +	l = w >> 3;
> +	e = w & 7;
> +#else
>  	l = w >> 1;
>  	e = w & 1;
> +#endif
>  
>  	for (j = 0; j < h; j++) {
>  		unsigned char *us = src1;
>  		unsigned char *vs = src2;
>  		unsigned int *vuvud = (unsigned int *) dst;
> +		unsigned short *vud;
>  
>  		for (i = 0; i < l; i++) {
> -#if X_BYTE_ORDER == X_BIG_ENDIAN
> +#ifdef __SSE2__
> +			_mm_storeu_si128(
> +				(void*)vuvud,
> +				_mm_unpacklo_epi8(
> +					_mm_loadl_epi64((void*)vs),
> +					_mm_loadl_epi64((void*)us)));
> +			vuvud+=4;
> +			us+=8;
> +			vs+=8;
> +#else /* __SSE2__ */
> +#  if X_BYTE_ORDER == X_BIG_ENDIAN
>  			*vuvud++ = (vs[0]<<24) | (us[0]<<16) | (vs[1]<<8) | us[1];
> -#else
> +#  else
>  			*vuvud++ = vs[0] | (us[0]<<8) | (vs[1]<<16) | (us[1]<<24);
> -#endif
> +#  endif
>  			us+=2;
>  			vs+=2;
> +#endif /* __SSE2__ */
>  		}
>  
> -		if (e) {
> -			unsigned short *vud = (unsigned short *) vuvud;
> +		vud = (unsigned short *)vuvud;
> +		for (i = 0; i < e; i++) {
>  #if X_BYTE_ORDER == X_BIG_ENDIAN
> -			*vud = us[0] | (vs[0]<<8);
> +			vud[i] = us[i] | (vs[i]<<8);
>  #else
> -			*vud = vs[0] | (us[0]<<8);
> +			vud[i] = vs[i] | (us[i]<<8);
>  #endif
>  		}
>  
> -- 
> 1.8.1.5

Cheers,
       Sven