avplay: don't request a stereo downmix
[ffmpeg.git] / libavcodec / x86 / cabac.h
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, cabac, 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, cabac, 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, cabac, 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, cabac, statep, low, lowword,        \
61                                     range, tmp)                              \
62         "movzbl " MANGLE(ff_h264_norm_shift) "("range"), %%ecx          \n\t"\
63         "shl    %%cl        , "range"                                   \n\t"\
64         "movzbl "MANGLE(ff_h264_mlps_state)"+128("ret"), "tmp"          \n\t"\
65         "shl    %%cl        , "low"                                     \n\t"\
66         "mov    "tmpbyte"   , "statep"                                  \n\t"\
67         "test   "lowword"   , "lowword"                                 \n\t"\
68         " jnz   1f                                                      \n\t"\
69         "mov "byte"("cabac"), %%"REG_c"                                 \n\t"\
70         "add"OPSIZE" $2     , "byte    "("cabac")                       \n\t"\
71         "movzwl (%%"REG_c")     , "tmp"                                 \n\t"\
72         "lea    -1("low")   , %%ecx                                     \n\t"\
73         "xor    "low"       , %%ecx                                     \n\t"\
74         "shr    $15         , %%ecx                                     \n\t"\
75         "bswap  "tmp"                                                   \n\t"\
76         "shr    $15         , "tmp"                                     \n\t"\
77         "movzbl " MANGLE(ff_h264_norm_shift) "(%%ecx), %%ecx            \n\t"\
78         "sub    $0xFFFF     , "tmp"                                     \n\t"\
79         "neg    %%ecx                                                   \n\t"\
80         "add    $7          , %%ecx                                     \n\t"\
81         "shl    %%cl        , "tmp"                                     \n\t"\
82         "add    "tmp"       , "low"                                     \n\t"\
83         "1:                                                             \n\t"
84
85 #if HAVE_7REGS && !defined(BROKEN_RELOCATIONS)
86 #define get_cabac_inline get_cabac_inline_x86
87 static av_always_inline int get_cabac_inline_x86(CABACContext *c,
88                                                  uint8_t *const state)
89 {
90     int bit, tmp;
91
92     __asm__ volatile(
93         BRANCHLESS_GET_CABAC("%0", "%5", "(%4)", "%1", "%w1", "%2",
94                              "%3", "%b3", "%a6")
95         :"=&r"(bit), "+&r"(c->low), "+&r"(c->range), "=&q"(tmp)
96         :"r"(state), "r"(c),
97          "i"(offsetof(CABACContext, bytestream))
98         : "%"REG_c, "memory"
99     );
100     return bit & 1;
101 }
102 #endif /* HAVE_7REGS && !defined(BROKEN_RELOCATIONS) */
103
104 #define get_cabac_bypass_sign get_cabac_bypass_sign_x86
105 static av_always_inline int get_cabac_bypass_sign_x86(CABACContext *c, int val)
106 {
107     x86_reg tmp;
108     __asm__ volatile(
109         "movl %a3(%2), %k1                      \n\t"
110         "movl %a4(%2), %%eax                    \n\t"
111         "shl $17, %k1                           \n\t"
112         "add %%eax, %%eax                       \n\t"
113         "sub %k1, %%eax                         \n\t"
114         "cltd                                   \n\t"
115         "and %%edx, %k1                         \n\t"
116         "add %k1, %%eax                         \n\t"
117         "xor %%edx, %%ecx                       \n\t"
118         "sub %%edx, %%ecx                       \n\t"
119         "test %%ax, %%ax                        \n\t"
120         " jnz 1f                                \n\t"
121         "mov  %a5(%2), %1                       \n\t"
122         "subl $0xFFFF, %%eax                    \n\t"
123         "movzwl (%1), %%edx                     \n\t"
124         "bswap %%edx                            \n\t"
125         "shrl $15, %%edx                        \n\t"
126         "add  $2, %1                            \n\t"
127         "addl %%edx, %%eax                      \n\t"
128         "mov  %1, %a5(%2)                       \n\t"
129         "1:                                     \n\t"
130         "movl %%eax, %a4(%2)                    \n\t"
131
132         :"+c"(val), "=&r"(tmp)
133         :"r"(c),
134          "i"(offsetof(CABACContext, range)), "i"(offsetof(CABACContext, low)),
135          "i"(offsetof(CABACContext, bytestream))
136         : "%eax", "%edx", "memory"
137     );
138     return val;
139 }
140
141 #endif /* AVCODEC_X86_CABAC_H */