mirror of
https://git.ffmpeg.org/ffmpeg.git
synced 2024-12-30 11:22:14 +00:00
115 lines
3.9 KiB
ArmAsm
115 lines
3.9 KiB
ArmAsm
/*
|
|
* Optimization of some functions from mpegvideo.c for armv5te
|
|
* Copyright (c) 2007 Siarhei Siamashka <ssvb@users.sourceforge.net>
|
|
*
|
|
* 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 "asm.S"
|
|
|
|
/*
|
|
* Special optimized version of dct_unquantize_h263_helper_c, it
|
|
* requires the block to be at least 8 bytes aligned, and may process
|
|
* more elements than requested. But it is guaranteed to never
|
|
* process more than 64 elements provided that count argument is <= 64,
|
|
* so it is safe. This function is optimized for a common distribution
|
|
* of values for nCoeffs (they are mostly multiple of 8 plus one or
|
|
* two extra elements). So this function processes data as 8 elements
|
|
* per loop iteration and contains optional 2 elements processing in
|
|
* the end.
|
|
*
|
|
* Inner loop should take 6 cycles per element on arm926ej-s (Nokia 770)
|
|
*/
|
|
|
|
.macro dequant_t dst, src, mul, add, tmp
|
|
rsbs \tmp, ip, \src, asr #16
|
|
it gt
|
|
addgt \tmp, \add, #0
|
|
it lt
|
|
rsblt \tmp, \add, #0
|
|
it ne
|
|
smlatbne \dst, \src, \mul, \tmp
|
|
.endm
|
|
|
|
.macro dequant_b dst, src, mul, add, tmp
|
|
rsbs \tmp, ip, \src, lsl #16
|
|
it gt
|
|
addgt \tmp, \add, #0
|
|
it lt
|
|
rsblt \tmp, \add, #0
|
|
it ne
|
|
smlabbne \dst, \src, \mul, \tmp
|
|
.endm
|
|
|
|
function ff_dct_unquantize_h263_armv5te, export=1
|
|
push {r4-r9,lr}
|
|
mov ip, #0
|
|
subs r3, r3, #2
|
|
ble 2f
|
|
ldrd r4, [r0, #0]
|
|
1:
|
|
ldrd r6, [r0, #8]
|
|
|
|
dequant_t r9, r4, r1, r2, r9
|
|
dequant_t lr, r5, r1, r2, lr
|
|
dequant_b r4, r4, r1, r2, r8
|
|
dequant_b r5, r5, r1, r2, r8
|
|
|
|
strh r4, [r0], #2
|
|
strh r9, [r0], #2
|
|
strh r5, [r0], #2
|
|
strh lr, [r0], #2
|
|
|
|
dequant_t r9, r6, r1, r2, r9
|
|
dequant_t lr, r7, r1, r2, lr
|
|
dequant_b r6, r6, r1, r2, r8
|
|
dequant_b r7, r7, r1, r2, r8
|
|
|
|
strh r6, [r0], #2
|
|
strh r9, [r0], #2
|
|
strh r7, [r0], #2
|
|
strh lr, [r0], #2
|
|
|
|
subs r3, r3, #8
|
|
it gt
|
|
ldrdgt r4, [r0, #0] /* load data early to avoid load/use pipeline stall */
|
|
bgt 1b
|
|
|
|
adds r3, r3, #2
|
|
it le
|
|
pople {r4-r9,pc}
|
|
2:
|
|
ldrsh r9, [r0, #0]
|
|
ldrsh lr, [r0, #2]
|
|
mov r8, r2
|
|
cmp r9, #0
|
|
it lt
|
|
rsblt r8, r2, #0
|
|
it ne
|
|
smlabbne r9, r9, r1, r8
|
|
mov r8, r2
|
|
cmp lr, #0
|
|
it lt
|
|
rsblt r8, r2, #0
|
|
it ne
|
|
smlabbne lr, lr, r1, r8
|
|
strh r9, [r0], #2
|
|
strh lr, [r0], #2
|
|
pop {r4-r9,pc}
|
|
endfunc
|