x86: af_volume: add SSE2-optimized s16 volume scaling

1 files changed, 56 insertions, 0 deletions

diff --git a/libavfilter/x86/af_volume.asm b/libavfilter/x86/af_volume.asm
new file mode 100644
index 0000000000..922ad5dcc4
--- /dev/null
+++ b/libavfilter/x86/af_volume.asm
@@ -0,0 +1,56 @@
+;*****************************************************************************
+;* x86-optimized functions for volume filter
+;* Copyright (c) 2012 Justin Ruggles <justin.ruggles@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 "libavutil/x86/x86inc.asm"
+
+SECTION_RODATA 32
+
+pw_1:   times 8 dw 1
+pw_128: times 8 dw 128
+
+SECTION_TEXT
+
+;------------------------------------------------------------------------------
+; void ff_scale_samples_s16(uint8_t *dst, const uint8_t *src, int len,
+;                           int volume)
+;------------------------------------------------------------------------------
+
+INIT_XMM sse2
+cglobal scale_samples_s16, 4,4,4, dst, src, len, volume
+    movd        m0, volumem
+    pshuflw     m0, m0, 0
+    punpcklwd   m0, [pw_1]
+    mova        m1, [pw_128]
+    lea       lenq, [lend*2-mmsize]
+.loop:
+    ; dst[i] = av_clip_int16((src[i] * volume + 128) >> 8);
+    mova        m2, [srcq+lenq]
+    punpcklwd   m3, m2, m1
+    punpckhwd   m2, m1
+    pmaddwd     m3, m0
+    pmaddwd     m2, m0
+    psrad       m3, 8
+    psrad       m2, 8
+    packssdw    m3, m2
+    mova  [dstq+lenq], m3
+    sub       lenq, mmsize
+    jge .loop
+    REP_RET