[FFmpeg-devel] [libav-devel] [PATCH] v210enc: Add x86 SIMD

[James Almer]

On 22/11/14 5:58 PM, Kieran Kunhya wrote:
> diff --git a/libavcodec/v210enc.h b/libavcodec/v210enc.h
> new file mode 100644
> index 0000000..b8b6143
> --- /dev/null
> +++ b/libavcodec/v210enc.h
> @@ -0,0 +1,31 @@
> +/*
> + * This file is part of Libav.

It shouldn't take long to make a patch that can be applied to the ffmpeg tree 
in a conflict free way...

> + *
> + * Libav is free software; you can redistribute it and/or
> + * modify it under the terms of the GNU Lesser General Public
> + * License as published by the Free Software Foundation; either
> + * version 2.1 of the License, or (at your option) any later version.
> + *
> + * Libav is distributed in the hope that it will be useful,
> + * but WITHOUT ANY WARRANTY; without even the implied warranty of
> + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
> + * Lesser General Public License for more details.
> + *
> + * You should have received a copy of the GNU Lesser General Public
> + * License along with Libav; if not, write to the Free Software
> + * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
> + */
> +
> +#ifndef AVCOENC_V210ENC_H
> +#define AVCOENC_V210ENC_H
> +
> +#include "libavutil/log.h"
> +#include "libavutil/opt.h"
> +
> +typedef struct {
> +    void (*pack_line)(const uint16_t *y, const uint16_t *u, const uint16_t *v, uint8_t *dst, ptrdiff_t width);
> +} V210EncContext;
> +
> +void v210enc_x86_init(V210EncContext *s);

ff_v210enc_init_x86

[...]

> diff --git a/libavcodec/x86/v210enc.asm b/libavcodec/x86/v210enc.asm
> new file mode 100644
> index 0000000..ca3edf4
> --- /dev/null
> +++ b/libavcodec/x86/v210enc.asm
> @@ -0,0 +1,76 @@
> +;******************************************************************************
> +;* V210 SIMD pack
> +;* Copyright (c) 2014 Kieran Kunhya <kierank at obe.tv>
> +;*
> +;* This file is part of Libav.
> +;*
> +;* Libav is free software; you can redistribute it and/or
> +;* modify it under the terms of the GNU Lesser General Public
> +;* License as published by the Free Software Foundation; either
> +;* version 2.1 of the License, or (at your option) any later version.
> +;*
> +;* Libav is distributed in the hope that it will be useful,
> +;* but WITHOUT ANY WARRANTY; without even the implied warranty of
> +;* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
> +;* Lesser General Public License for more details.
> +;*
> +;* You should have received a copy of the GNU Lesser General Public
> +;* License along with Libav; if not, write to the Free Software
> +;* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
> +;******************************************************************************
> +
> +%include "libavutil/x86/x86util.asm"
> +
> +SECTION_RODATA
> +
> +v210_enc_min: times 8 dw 0x4
> +v210_enc_max: times 8 dw 0x3fb
> +
> +v210_enc_luma_mult: dw 4,1,16,4,1,16,0,0
> +v210_enc_luma_shuf: db -1,0,1,-1,2,3,4,5,-1,6,7,-1,8,9,10,11
> +
> +v210_enc_chroma_mult: dw 1,4,16,0,16,1,4,0
> +v210_enc_chroma_shuf: db 0,1,8,9,-1,2,3,-1,10,11,4,5,-1,12,13,-1
> +
> +SECTION .text
> +
> +%macro v210_planar_pack 0
> +
> +; v210_planar_pack(const uint16_t *y, const uint16_t *u, const uint16_t *v, uint8_t *dst, ptrdiff_t width)
> +cglobal v210_planar_pack, 5, 5, 4, y, u, v, dst, width
> +    lea     r0, [r0+2*widthq]
> +    add     uq, widthq
> +    add     vq, widthq
> +    neg     widthq
> +
> +    movu    m2, [v210_enc_min]
> +    movu    m3, [v210_enc_max]

mova, they are aligned and declared on this same file.

You may be able to use mova below as well, but I don't know if AVFrame->data and AVPacket->data 
are aligned here.
It's probably worth a try.

> +
> +.loop
> +    movu    m0, [yq+2*widthq]
> +    CLIPW   m0, m2, m3
> +
> +    movq    m1, [uq+widthq]
> +    movhps  m1, [vq+widthq]
> +    CLIPW   m1, m2, m3
> +
> +    pmullw  m0, [v210_enc_luma_mult]
> +    pshufb  m0, [v210_enc_luma_shuf]
> +
> +    pmullw  m1, [v210_enc_chroma_mult]
> +    pshufb  m1, [v210_enc_chroma_shuf]
> +
> +    por     m0, m1
> +
> +    movu    [dstq], m0
> +
> +    add     dstq, mmsize
> +    add     widthq, 6
> +    jl .loop
> +
> +    REP_RET

This is an SSSE3 function, so RET can be used instead (REP_RET is only really needed for SSE3 and below).

> +%endmacro
> +
> +INIT_XMM ssse3
> +v210_planar_pack
> +
> diff --git a/libavcodec/x86/v210enc_init.c b/libavcodec/x86/v210enc_init.c
> new file mode 100644
> index 0000000..524ec7a
> --- /dev/null
> +++ b/libavcodec/x86/v210enc_init.c
> @@ -0,0 +1,31 @@
> +/*
> + * This file is part of Libav.
> + *
> + * Libav is free software; you can redistribute it and/or
> + * modify it under the terms of the GNU Lesser General Public
> + * License as published by the Free Software Foundation; either
> + * version 2.1 of the License, or (at your option) any later version.
> + *
> + * Libav is distributed in the hope that it will be useful,
> + * but WITHOUT ANY WARRANTY; without even the implied warranty of
> + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
> + * Lesser General Public License for more details.
> + *
> + * You should have received a copy of the GNU Lesser General Public
> + * License along with Libav; if not, write to the Free Software
> + * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
> + */
> +
> +#include "libavutil/x86/asm.h"

Not needed. It's for inline asm only.

> +#include "libavutil/x86/cpu.h"
> +#include "libavcodec/v210enc.h"
> +
> +extern void ff_v210_planar_pack_ssse3(const uint16_t *y, const uint16_t *u, const uint16_t *v, uint8_t *dst, ptrdiff_t width);

No need to use extern.

> +
> +av_cold void v210enc_x86_init(V210EncContext *s)
> +{
> +    int cpu_flags = av_get_cpu_flags();
> +
> +    if( EXTERNAL_SSSE3(cpu_flags) )
> +        s->pack_line = ff_v210_planar_pack_ssse3;
> +}
>