[FFmpeg-devel] [PATCH v7] libavfilter/x86/vf_convolution: add sobel filter optimization and unit test with intel AVX512 VNNI

[Wang, Bin]

-----Original Message-----
From: ffmpeg-devel <ffmpeg-devel-bounces at ffmpeg.org> On Behalf Of James Almer
Sent: Monday, November 14, 2022 10:43 AM
To: ffmpeg-devel at ffmpeg.org
Subject: Re: [FFmpeg-devel] [PATCH v7] libavfilter/x86/vf_convolution: add sobel filter optimization and unit test with intel AVX512 VNNI

On 11/4/2022 5:29 AM, bin.wang-at-intel.com at ffmpeg.org wrote:
> +%macro FILTER_SOBEL 0
> +%if UNIX64
> +cglobal filter_sobel, 4, 15, 7, dst, width, matrix, ptr, c0, c1, c2, 
> +c3, c4, c5, c6, c7, c8, r, x %else cglobal filter_sobel, 4, 15, 7, 
> +dst, width, rdiv, bias, matrix, ptr, c0, c1, c2, c3, c4, c5, c6, c7, 
> +c8, r, x %endif %if WIN64
> +    SWAP xmm0, xmm2
> +    SWAP xmm1, xmm3
> +    mov  r2q, matrixmp
> +    mov  r3q, ptrmp
> +    DEFINE_ARGS dst, width, matrix, ptr, c0, c1, c2, c3, c4, c5, c6, 
> +c7, c8, r, x %endif
> +    movsxdifnidn widthq, widthd
> +    VBROADCASTSS m0, xmm0
> +    VBROADCASTSS m1, xmm1

> + This and every other xmm# case should instead be xm#, to ensure the swapping is taken into account.

Sorry, I can't get your point, could you please help to explain why I have to use xm# to ensure the swapping operation(swap xmm# can't work in WIN64 asm)? And How to do it ?