mirror of https://github.com/FFmpeg/FFmpeg.git
You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
108 lines
5.1 KiB
108 lines
5.1 KiB
/* |
|
* 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 |
|
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA |
|
*/ |
|
|
|
#ifndef AVCODEC_ARM_CABAC_H |
|
#define AVCODEC_ARM_CABAC_H |
|
|
|
#include "config.h" |
|
#if HAVE_ARMV6T2_INLINE |
|
|
|
#include "libavutil/attributes.h" |
|
#include "libavutil/internal.h" |
|
#include "libavcodec/cabac.h" |
|
|
|
#define get_cabac_inline get_cabac_inline_arm |
|
static av_always_inline int get_cabac_inline_arm(CABACContext *c, |
|
uint8_t *const state) |
|
{ |
|
int bit; |
|
void *reg_b, *reg_c, *tmp; |
|
|
|
__asm__ volatile( |
|
"ldrb %[bit] , [%[state]] \n\t" |
|
"add %[r_b] , %[tables] , %[lps_off] \n\t" |
|
"mov %[tmp] , %[range] \n\t" |
|
"and %[range] , %[range] , #0xC0 \n\t" |
|
"add %[r_b] , %[r_b] , %[bit] \n\t" |
|
"ldrb %[range] , [%[r_b], %[range], lsl #1] \n\t" |
|
"add %[r_b] , %[tables] , %[norm_off] \n\t" |
|
"sub %[r_c] , %[tmp] , %[range] \n\t" |
|
"lsl %[tmp] , %[r_c] , #17 \n\t" |
|
"cmp %[tmp] , %[low] \n\t" |
|
"it gt \n\t" |
|
"movgt %[range] , %[r_c] \n\t" |
|
"itt cc \n\t" |
|
"mvncc %[bit] , %[bit] \n\t" |
|
"subcc %[low] , %[low] , %[tmp] \n\t" |
|
"add %[r_c] , %[tables] , %[mlps_off] \n\t" |
|
"ldrb %[tmp] , [%[r_b], %[range]] \n\t" |
|
"ldrb %[r_b] , [%[r_c], %[bit]] \n\t" |
|
"lsl %[low] , %[low] , %[tmp] \n\t" |
|
"lsl %[range] , %[range] , %[tmp] \n\t" |
|
"uxth %[r_c] , %[low] \n\t" |
|
"strb %[r_b] , [%[state]] \n\t" |
|
"tst %[r_c] , %[r_c] \n\t" |
|
"bne 2f \n\t" |
|
"ldr %[r_c] , [%[c], %[byte]] \n\t" |
|
#if UNCHECKED_BITSTREAM_READER |
|
"ldrh %[tmp] , [%[r_c]] \n\t" |
|
"add %[r_c] , %[r_c] , #2 \n\t" |
|
"str %[r_c] , [%[c], %[byte]] \n\t" |
|
#else |
|
"ldr %[r_b] , [%[c], %[end]] \n\t" |
|
"ldrh %[tmp] , [%[r_c]] \n\t" |
|
"cmp %[r_c] , %[r_b] \n\t" |
|
"itt lt \n\t" |
|
"addlt %[r_c] , %[r_c] , #2 \n\t" |
|
"strlt %[r_c] , [%[c], %[byte]] \n\t" |
|
#endif |
|
"sub %[r_c] , %[low] , #1 \n\t" |
|
"add %[r_b] , %[tables] , %[norm_off] \n\t" |
|
"eor %[r_c] , %[low] , %[r_c] \n\t" |
|
"rev %[tmp] , %[tmp] \n\t" |
|
"lsr %[r_c] , %[r_c] , #15 \n\t" |
|
"lsr %[tmp] , %[tmp] , #15 \n\t" |
|
"ldrb %[r_c] , [%[r_b], %[r_c]] \n\t" |
|
"movw %[r_b] , #0xFFFF \n\t" |
|
"sub %[tmp] , %[tmp] , %[r_b] \n\t" |
|
"rsb %[r_c] , %[r_c] , #7 \n\t" |
|
"lsl %[tmp] , %[tmp] , %[r_c] \n\t" |
|
"add %[low] , %[low] , %[tmp] \n\t" |
|
"2: \n\t" |
|
: [bit]"=&r"(bit), |
|
[low]"+&r"(c->low), |
|
[range]"+&r"(c->range), |
|
[r_b]"=&r"(reg_b), |
|
[r_c]"=&r"(reg_c), |
|
[tmp]"=&r"(tmp) |
|
: [c]"r"(c), |
|
[state]"r"(state), |
|
[tables]"r"(ff_h264_cabac_tables), |
|
[byte]"M"(offsetof(CABACContext, bytestream)), |
|
[end]"M"(offsetof(CABACContext, bytestream_end)), |
|
[norm_off]"I"(H264_NORM_SHIFT_OFFSET), |
|
[lps_off]"I"(H264_LPS_RANGE_OFFSET), |
|
[mlps_off]"I"(H264_MLPS_STATE_OFFSET + 128) |
|
: "memory", "cc" |
|
); |
|
|
|
return bit & 1; |
|
} |
|
#endif /* HAVE_ARMV6T2_INLINE */ |
|
|
|
#endif /* AVCODEC_ARM_CABAC_H */
|
|
|