ffmpeg/libavcodec/x86/sbrdsp_init.c
Christophe GISQUET 34454c761f SBR DSP x86: implement SSE sbr_sum_square_sse
The 32bits targets have been compiled with -mfpmath=sse for proper reference.
sbr_sum_square C  /32bits: 82c (unrolled)/102c
               C  /64bits: 69c (unrolled)/82c
               SSE/32bits: 42c
               SSE/64bits: 31c

Use of SSE4.1 dpps to perform the final sum is slower.
Not unrolling to perform 8 operations in a loop yields 10 more cycles.

Signed-off-by: Ronald S. Bultje <rsbultje@gmail.com>
2012-02-23 15:50:06 -08:00

38 lines
1.2 KiB
C

/*
* AAC Spectral Band Replication decoding functions
* Copyright (c) 2012 Christophe Gisquet <christophe.gisquet@gmail.com>
*
* 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 "config.h"
#include "libavutil/cpu.h"
#include "libavcodec/sbrdsp.h"
float ff_sbr_sum_square_sse(float (*x)[2], int n);
void ff_sbrdsp_init_x86(SBRDSPContext *s)
{
if (HAVE_YASM) {
int mm_flags = av_get_cpu_flags();
if (mm_flags & AV_CPU_FLAG_SSE) {
s->sum_square = ff_sbr_sum_square_sse;
}
}
}