Main Page
Related Pages
Modules
Data Structures
Files
Examples
File List
Globals
libavcodec
x86
cabac.h
Go to the documentation of this file.
1
/*
2
* Copyright (c) 2003 Michael Niedermayer <michaelni@gmx.at>
3
*
4
* This file is part of Libav.
5
*
6
* Libav is free software; you can redistribute it and/or
7
* modify it under the terms of the GNU Lesser General Public
8
* License as published by the Free Software Foundation; either
9
* version 2.1 of the License, or (at your option) any later version.
10
*
11
* Libav is distributed in the hope that it will be useful,
12
* but WITHOUT ANY WARRANTY; without even the implied warranty of
13
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14
* Lesser General Public License for more details.
15
*
16
* You should have received a copy of the GNU Lesser General Public
17
* License along with Libav; if not, write to the Free Software
18
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
19
*/
20
21
#ifndef AVCODEC_X86_CABAC_H
22
#define AVCODEC_X86_CABAC_H
23
24
#include "
libavcodec/cabac.h
"
25
#include "
libavutil/attributes.h
"
26
#include "
libavutil/x86_cpu.h
"
27
#include "config.h"
28
29
#if HAVE_FAST_CMOV
30
#define BRANCHLESS_GET_CABAC_UPDATE(ret, statep, low, lowword, range, tmp)\
31
"mov "tmp" , %%ecx \n\t"\
32
"shl $17 , "tmp" \n\t"\
33
"cmp "low" , "tmp" \n\t"\
34
"cmova %%ecx , "range" \n\t"\
35
"sbb %%ecx , %%ecx \n\t"\
36
"and %%ecx , "tmp" \n\t"\
37
"xor %%ecx , "ret" \n\t"\
38
"sub "tmp" , "low" \n\t"
39
#else
/* HAVE_FAST_CMOV */
40
#define BRANCHLESS_GET_CABAC_UPDATE(ret, statep, low, lowword, range, tmp)\
41
"mov "tmp" , %%ecx \n\t"\
42
"shl $17 , "tmp" \n\t"\
43
"sub "low" , "tmp" \n\t"\
44
"sar $31 , "tmp" \n\t"
/*lps_mask*/
\
45
"sub %%ecx , "range" \n\t"
/*RangeLPS - range*/
\
46
"and "tmp" , "range" \n\t"
/*(RangeLPS - range)&lps_mask*/
\
47
"add %%ecx , "range" \n\t"
/*new range*/
\
48
"shl $17 , %%ecx \n\t"\
49
"and "tmp" , %%ecx \n\t"\
50
"sub %%ecx , "low" \n\t"\
51
"xor "tmp" , "ret" \n\t"
52
#endif
/* HAVE_FAST_CMOV */
53
54
#define BRANCHLESS_GET_CABAC(ret, statep, low, lowword, range, tmp, tmpbyte, byte) \
55
"movzbl "statep" , "ret" \n\t"\
56
"mov "range" , "tmp" \n\t"\
57
"and $0xC0 , "range" \n\t"\
58
"movzbl "MANGLE(ff_h264_lps_range)"("ret", "range", 2), "range" \n\t"\
59
"sub "range" , "tmp" \n\t"\
60
BRANCHLESS_GET_CABAC_UPDATE(ret, statep, low, lowword, range, tmp) \
61
"movzbl " MANGLE(ff_h264_norm_shift) "("range"), %%ecx \n\t"\
62
"shl %%cl , "range" \n\t"\
63
"movzbl "MANGLE(ff_h264_mlps_state)"+128("ret"), "tmp" \n\t"\
64
"shl %%cl , "low" \n\t"\
65
"mov "tmpbyte" , "statep" \n\t"\
66
"test "lowword" , "lowword" \n\t"\
67
" jnz 1f \n\t"\
68
"mov "byte" , %%"REG_c" \n\t"\
69
"add"OPSIZE" $2 , "byte" \n\t"\
70
"movzwl (%%"REG_c") , "tmp" \n\t"\
71
"lea -1("low") , %%ecx \n\t"\
72
"xor "low" , %%ecx \n\t"\
73
"shr $15 , %%ecx \n\t"\
74
"bswap "tmp" \n\t"\
75
"shr $15 , "tmp" \n\t"\
76
"movzbl " MANGLE(ff_h264_norm_shift) "(%%ecx), %%ecx \n\t"\
77
"sub $0xFFFF , "tmp" \n\t"\
78
"neg %%ecx \n\t"\
79
"add $7 , %%ecx \n\t"\
80
"shl %%cl , "tmp" \n\t"\
81
"add "tmp" , "low" \n\t"\
82
"1: \n\t"
83
84
#if HAVE_7REGS && !defined(BROKEN_RELOCATIONS)
85
#define get_cabac_inline get_cabac_inline_x86
86
static
av_always_inline
int
get_cabac_inline_x86(
CABACContext
*c,
87
uint8_t *
const
state
)
88
{
89
int
bit, tmp;
90
91
__asm__
volatile
(
92
BRANCHLESS_GET_CABAC
(
"%0"
,
"(%5)"
,
"%1"
,
"%w1"
,
"%2"
,
93
"%3"
,
"%b3"
,
"%4"
)
94
:
"=&r"
(bit),
"+&r"
(c->
low
),
"+&r"
(c->
range
),
"=&q"
(tmp),
95
"+m"
(c->
bytestream
)
96
:
"r"
(state)
97
:
"%"
REG_c,
"memory"
98
);
99
return
bit & 1;
100
}
101
#endif
/* HAVE_7REGS && !defined(BROKEN_RELOCATIONS) */
102
103
#define get_cabac_bypass_sign get_cabac_bypass_sign_x86
104
static
av_always_inline
int
get_cabac_bypass_sign_x86
(
CABACContext
*c,
int
val)
105
{
106
x86_reg
tmp;
107
__asm__
volatile
(
108
"movl %4, %k1 \n\t"
109
"movl %2, %%eax \n\t"
110
"shl $17, %k1 \n\t"
111
"add %%eax, %%eax \n\t"
112
"sub %k1, %%eax \n\t"
113
"cltd \n\t"
114
"and %%edx, %k1 \n\t"
115
"add %k1, %%eax \n\t"
116
"xor %%edx, %%ecx \n\t"
117
"sub %%edx, %%ecx \n\t"
118
"test %%ax, %%ax \n\t"
119
" jnz 1f \n\t"
120
"mov %3, %1 \n\t"
121
"subl $0xFFFF, %%eax \n\t"
122
"movzwl (%1), %%edx \n\t"
123
"bswap %%edx \n\t"
124
"shrl $15, %%edx \n\t"
125
"add $2, %1 \n\t"
126
"addl %%edx, %%eax \n\t"
127
"mov %1, %3 \n\t"
128
"1: \n\t"
129
"movl %%eax, %2 \n\t"
130
131
:
"+c"
(val),
"=&r"
(tmp),
"+m"
(c->
low
),
"+m"
(c->
bytestream
)
132
:
"m"
(c->
range
)
133
:
"%eax"
,
"%edx"
134
);
135
return
val;
136
}
137
138
#endif
/* AVCODEC_X86_CABAC_H */
BRANCHLESS_GET_CABAC
#define BRANCHLESS_GET_CABAC(ret, statep, low, lowword, range, tmp, tmpbyte, byte)
Definition:
cabac.h:54
x86_reg
int x86_reg
Definition:
x86_cpu.h:68
attributes.h
Macro definitions for various function/variable attributes.
get_cabac_bypass_sign_x86
static av_always_inline int get_cabac_bypass_sign_x86(CABACContext *c, int val)
Definition:
cabac.h:104
CABACContext::bytestream
const uint8_t * bytestream
Definition:
cabac.h:42
CABACContext
Definition:
cabac.h:37
CABACContext::range
int range
Definition:
cabac.h:39
state
static uint32_t state
Definition:
trasher.c:25
CABACContext::low
int low
Definition:
cabac.h:38
av_always_inline
#define av_always_inline
Definition:
attributes.h:39
x86_cpu.h
cabac.h
Context Adaptive Binary Arithmetic Coder.