[FFmpeg-devel] [PATCH v3] aacenc: add SIMD optimizations for abs_pow34 and quantization

James Almer jamrial at gmail.com
Tue Oct 18 18:32:43 EEST 2016


On 10/18/2016 12:07 PM, Rostislav Pehlivanov wrote:
> diff --git a/libavcodec/aacenc.c b/libavcodec/aacenc.c
> index ee3cbf8..622f0ba 100644
> --- a/libavcodec/aacenc.c
> +++ b/libavcodec/aacenc.c
> @@ -1033,6 +1033,12 @@ static av_cold int aac_encode_init(AVCodecContext *avctx)
>      ff_lpc_init(&s->lpc, 2*avctx->frame_size, TNS_MAX_ORDER, FF_LPC_TYPE_LEVINSON);
>      s->random_state = 0x1f2e3d4c;
>  
> +    s->abs_pow34   = &abs_pow34_v;
> +    s->quant_bands = &quantize_bands;

No need for & in these.

> +
> +    if (ARCH_X86)
> +        ff_aac_dsp_init_x86(s);
> +
>      if (HAVE_MIPSDSP)
>          ff_aac_coder_init_mips(s);

[...]

> diff --git a/libavcodec/x86/aacencdsp.asm b/libavcodec/x86/aacencdsp.asm
> new file mode 100644
> index 0000000..dd7b022
> --- /dev/null
> +++ b/libavcodec/x86/aacencdsp.asm
> @@ -0,0 +1,88 @@
> +;******************************************************************************
> +;* SIMD optimized AAC encoder DSP functions
> +;*
> +;* Copyright (C) 2016 Rostislav Pehlivanov <atomnuker at gmail.com>
> +;*
> +;* This file is part of FFmpeg.
> +;*
> +;* FFmpeg 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.
> +;*
> +;* FFmpeg 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 FFmpeg; 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
> +
> +float_abs_mask: times 4 dd 0x7fffffff
> +
> +SECTION .text
> +
> +;*******************************************************************
> +;void ff_abs_pow34(float *out, const float *in, const int size);
> +;*******************************************************************
> +INIT_XMM sse
> +cglobal abs_pow34, 3, 3, 3, out, in, size
> +    mova   m2, [float_abs_mask]
> +    shl    sizeq, 2
> +    add    inq, sizeq
> +    add    outq, sizeq
> +    neg    sizeq
> +.loop:
> +    movaps m0, [inq+sizeq]
> +    andps  m0, m2

Remove the movaps and do

andps  m0, m2, [inq+sizeq]

Instead. Sorry i didn't notice this last time.

> +    sqrtps m1, m0
> +    mulps  m0, m1
> +    sqrtps m0, m0
> +    mova   [outq+sizeq], m0
> +    add    sizeq, mmsize
> +    jl    .loop
> +    RET
> +
> +;*******************************************************************
> +;void ff_aac_quantize_bands(int *out, const float *in, const float *scaled,
> +;                           int size, int is_signed, int maxval, const float Q34,
> +;                           const float rounding)
> +;*******************************************************************
> +INIT_XMM sse2
> +cglobal aac_quantize_bands, 5, 5, 6, out, in, scaled, size, is_signed, maxval, Q34, rounding
> +%if UNIX64 == 0
> +    movss     m0, Q34m
> +    movss     m1, roundingm
> +    cvtsi2ss  m3, maxvald
> +%else
> +    cvtsi2ss  m3, dword maxvalm
> +%endif

The other way around. Unix64 is the one that has maxval on a reg regardless
of how you init the function, whereas win64 and any x86_32 target have it
on stack.

> +    shufps    m0, m0, 0
> +    shufps    m1, m1, 0
> +    shufps    m3, m3, 0
> +    shl       is_signedd, 31
> +    movd      m4, is_signedd
> +    shufps    m4, m4, 0
> +    shl       sized,   2
> +    add       inq, sizeq
> +    add       outq, sizeq
> +    add       scaledq, sizeq
> +    neg       sizeq
> +.loop:
> +    mulps     m2, m0, [scaledq+sizeq]
> +    addps     m2, m1
> +    minps     m2, m3

> +    movaps    m5, [inq+sizeq]
> +    andps     m5, m4

Same as in abs_pow34, remove movaps and do

andps     m5, m4, [inq+sizeq]

> +    orps      m2, m5
> +    cvttps2dq m2, m2
> +    mova      [outq+sizeq], m2
> +    add       sizeq, mmsize
> +    jl       .loop
> +    RET
> diff --git a/libavcodec/x86/aacencdsp_init.c b/libavcodec/x86/aacencdsp_init.c
> new file mode 100644
> index 0000000..aefaa15
> --- /dev/null
> +++ b/libavcodec/x86/aacencdsp_init.c
> @@ -0,0 +1,43 @@
> +/*
> + * AAC encoder assembly optimizations
> + * Copyright (C) 2016 Rostislav Pehlivanov <atomnuker at gmail.com>
> + *
> + * This file is part of FFmpeg.
> + *
> + * FFmpeg 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.
> + *
> + * FFmpeg 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 FFmpeg; if not, write to the Free Software
> + * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
> + */
> +
> +#include "config.h"
> +
> +#include "libavutil/float_dsp.h"
> +#include "libavutil/x86/cpu.h"
> +#include "libavcodec/aacenc.h"
> +
> +void ff_abs_pow34_sse(float *out, const float *in, const int size);
> +
> +void ff_aac_quantize_bands_sse2(int *out, const float *in, const float *scaled,
> +                                int size, int is_signed, int maxval, const float Q34,
> +                                const float rounding);
> +
> +av_cold void ff_aac_dsp_init_x86(AACEncContext *s)
> +{
> +    int cpu_flags = av_get_cpu_flags();
> +
> +    if (EXTERNAL_SSE(cpu_flags))
> +        s->abs_pow34   = &ff_abs_pow34_sse;
> +
> +    if (EXTERNAL_SSE2(cpu_flags))
> +        s->quant_bands = &ff_aac_quantize_bands_sse2;

Same with these.

Passes fate on mingw-w64 (x86_64) after fixing the maxval mixup above.
Crashes otherwise.



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