ffmpeg/libavcodec/x86/ac3dsp.asm
Justin Ruggles 7539a1fee2 ac3enc: Add x86-optimized function to speed up log2_tab().
AC3DSPContext.ac3_max_msb_abs_int16() finds the maximum MSB of the absolute
value of each element in an array of int16_t.

Signed-off-by: Ronald S. Bultje <rsbultje@gmail.com>
(cherry picked from commit fbb6b49dab)
2011-02-14 23:58:20 +01:00

137 lines
3.9 KiB
NASM

;*****************************************************************************
;* x86-optimized AC-3 DSP utils
;* Copyright (c) 2011 Justin Ruggles
;*
;* 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
;* 51, Inc., Foundation Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
;******************************************************************************
%include "x86inc.asm"
%include "x86util.asm"
SECTION .text
;-----------------------------------------------------------------------------
; void ff_ac3_exponent_min(uint8_t *exp, int num_reuse_blocks, int nb_coefs)
;-----------------------------------------------------------------------------
%macro AC3_EXPONENT_MIN 1
cglobal ac3_exponent_min_%1, 3,4,2, exp, reuse_blks, expn, offset
shl reuse_blksq, 8
jz .end
LOOP_ALIGN
.nextexp:
mov offsetq, reuse_blksq
mova m0, [expq+offsetq]
sub offsetq, 256
LOOP_ALIGN
.nextblk:
PMINUB m0, [expq+offsetq], m1
sub offsetq, 256
jae .nextblk
mova [expq], m0
add expq, mmsize
sub expnq, mmsize
jg .nextexp
.end:
REP_RET
%endmacro
%define PMINUB PMINUB_MMX
%define LOOP_ALIGN
INIT_MMX
AC3_EXPONENT_MIN mmx
%ifdef HAVE_MMX2
%define PMINUB PMINUB_MMXEXT
%define LOOP_ALIGN ALIGN 16
AC3_EXPONENT_MIN mmxext
%endif
%ifdef HAVE_SSE
INIT_XMM
AC3_EXPONENT_MIN sse2
%endif
%undef PMINUB
%undef LOOP_ALIGN
;-----------------------------------------------------------------------------
; int ff_ac3_max_msb_abs_int16(const int16_t *src, int len)
;
; This function uses 2 different methods to calculate a valid result.
; 1) logical 'or' of abs of each element
; This is used for ssse3 because of the pabsw instruction.
; It is also used for mmx because of the lack of min/max instructions.
; 2) calculate min/max for the array, then or(abs(min),abs(max))
; This is used for mmxext and sse2 because they have pminsw/pmaxsw.
;-----------------------------------------------------------------------------
%macro AC3_MAX_MSB_ABS_INT16 2
cglobal ac3_max_msb_abs_int16_%1, 2,2,5, src, len
pxor m2, m2
pxor m3, m3
.loop:
%ifidn %2, min_max
mova m0, [srcq]
mova m1, [srcq+mmsize]
pminsw m2, m0
pminsw m2, m1
pmaxsw m3, m0
pmaxsw m3, m1
%else ; or_abs
%ifidn %1, mmx
mova m0, [srcq]
mova m1, [srcq+mmsize]
ABS2 m0, m1, m3, m4
%else ; ssse3
; using memory args is faster for ssse3
pabsw m0, [srcq]
pabsw m1, [srcq+mmsize]
%endif
por m2, m0
por m2, m1
%endif
add srcq, mmsize*2
sub lend, mmsize
ja .loop
%ifidn %2, min_max
ABS2 m2, m3, m0, m1
por m2, m3
%endif
%ifidn mmsize, 16
mova m0, m2
punpckhqdq m0, m0
por m2, m0
%endif
PSHUFLW m0, m2, 0xe
por m2, m0
PSHUFLW m0, m2, 0x1
por m2, m0
movd eax, m2
and eax, 0xFFFF
RET
%endmacro
INIT_MMX
%define ABS2 ABS2_MMX
%define PSHUFLW pshufw
AC3_MAX_MSB_ABS_INT16 mmx, or_abs
%define ABS2 ABS2_MMX2
AC3_MAX_MSB_ABS_INT16 mmxext, min_max
INIT_XMM
%define PSHUFLW pshuflw
AC3_MAX_MSB_ABS_INT16 sse2, min_max
%define ABS2 ABS2_SSSE3
AC3_MAX_MSB_ABS_INT16 ssse3, or_abs