FFmpeg/libavcodec/arm/ac3dsp_arm.S
Mans Rullgard aa05f2126e ac3enc: ARM optimised ac3_compute_matissa_size
Signed-off-by: Mans Rullgard <mans@mansr.com>
2011-04-01 22:46:21 +01:00

53 lines
1.7 KiB
ArmAsm

/*
* Copyright (c) 2011 Mans Rullgard <mans@mansr.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 "asm.S"
function ff_ac3_compute_mantissa_size_arm, export=1
push {r4-r8,lr}
ldm r0, {r4-r8}
mov r3, r0
mov r0, #0
1:
ldrb lr, [r1], #1
subs r2, r2, #1
blt 2f
cmp lr, #4
bgt 3f
subs lr, lr, #1
addlt r4, r4, #1
addeq r5, r5, #1
ble 1b
subs lr, lr, #2
addlt r6, r6, #1
addeq r7, r7, #1
addgt r8, r8, #1
b 1b
3:
cmp lr, #14
sublt lr, lr, #1
addgt r0, r0, #16
addle r0, r0, lr
b 1b
2:
stm r3, {r4-r8}
pop {r4-r8,pc}
endfunc