Merge commit '502512ea0f179165782777265f441d4061ff6012'
[ffmpeg.git] / libavcodec / x86 / cabac.h
1 /*
2  * Copyright (c) 2003 Michael Niedermayer <michaelni@gmx.at>
3  *
4  * This file is part of FFmpeg.
5  *
6  * FFmpeg 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  * FFmpeg 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 FFmpeg; 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/macros.h"
27 #include "libavutil/x86/asm.h"
28 #include "config.h"
29
30 #if   (defined(__i386) && defined(__clang__) && (__clang_major__<2 || (__clang_major__==2 && __clang_minor__<10)))\
31    || (                  !defined(__clang__) && defined(__llvm__) && __GNUC__==4 && __GNUC_MINOR__==2 && __GNUC_PATCHLEVEL__<=1)\
32    || (defined(__INTEL_COMPILER) && defined(_MSC_VER))
33 #       define BROKEN_COMPILER 1
34 #else
35 #       define BROKEN_COMPILER 0
36 #endif
37
38 #if HAVE_INLINE_ASM
39
40 #ifndef UNCHECKED_BITSTREAM_READER
41 #define UNCHECKED_BITSTREAM_READER !CONFIG_SAFE_BITSTREAM_READER
42 #endif
43
44 #if UNCHECKED_BITSTREAM_READER
45 #define END_CHECK(end) ""
46 #else
47 #define END_CHECK(end) \
48         "cmp    "end"       , %%"REG_c"                                 \n\t"\
49         "jge    1f                                                      \n\t"
50 #endif
51
52 #ifdef BROKEN_RELOCATIONS
53 #define TABLES_ARG , "r"(tables)
54
55 #if HAVE_FAST_CMOV
56 #define BRANCHLESS_GET_CABAC_UPDATE(ret, retq, low, range, tmp) \
57         "cmp    "low"       , "tmp"                        \n\t"\
58         "cmova  %%ecx       , "range"                      \n\t"\
59         "sbb    %%rcx       , %%rcx                        \n\t"\
60         "and    %%ecx       , "tmp"                        \n\t"\
61         "xor    %%rcx       , "retq"                       \n\t"\
62         "sub    "tmp"       , "low"                        \n\t"
63 #else /* HAVE_FAST_CMOV */
64 #define BRANCHLESS_GET_CABAC_UPDATE(ret, retq, low, range, tmp) \
65 /* P4 Prescott has crappy cmov,sbb,64bit shift so avoid them */ \
66         "sub    "low"       , "tmp"                        \n\t"\
67         "sar    $31         , "tmp"                        \n\t"\
68         "sub    %%ecx       , "range"                      \n\t"\
69         "and    "tmp"       , "range"                      \n\t"\
70         "add    %%ecx       , "range"                      \n\t"\
71         "shl    $17         , %%ecx                        \n\t"\
72         "and    "tmp"       , %%ecx                        \n\t"\
73         "sub    %%ecx       , "low"                        \n\t"\
74         "xor    "tmp"       , "ret"                        \n\t"\
75         "movslq "ret"       , "retq"                       \n\t"
76 #endif /* HAVE_FAST_CMOV */
77
78 #define BRANCHLESS_GET_CABAC(ret, retq, statep, low, lowword, range, rangeq, tmp, tmpbyte, byte, end, norm_off, lps_off, mlps_off, tables) \
79         "movzbl "statep"    , "ret"                                     \n\t"\
80         "mov    "range"     , "tmp"                                     \n\t"\
81         "and    $0xC0       , "range"                                   \n\t"\
82         "lea    ("ret", "range", 2), %%ecx                              \n\t"\
83         "movzbl "lps_off"("tables", %%rcx), "range"                     \n\t"\
84         "sub    "range"     , "tmp"                                     \n\t"\
85         "mov    "tmp"       , %%ecx                                     \n\t"\
86         "shl    $17         , "tmp"                                     \n\t"\
87         BRANCHLESS_GET_CABAC_UPDATE(ret, retq, low, range, tmp)              \
88         "movzbl "norm_off"("tables", "rangeq"), %%ecx                   \n\t"\
89         "shl    %%cl        , "range"                                   \n\t"\
90         "movzbl "mlps_off"+128("tables", "retq"), "tmp"                 \n\t"\
91         "shl    %%cl        , "low"                                     \n\t"\
92         "mov    "tmpbyte"   , "statep"                                  \n\t"\
93         "test   "lowword"   , "lowword"                                 \n\t"\
94         "jnz    2f                                                      \n\t"\
95         "mov    "byte"      , %%"REG_c"                                 \n\t"\
96         END_CHECK(end)\
97         "add"OPSIZE" $2     , "byte"                                    \n\t"\
98         "1:                                                             \n\t"\
99         "movzwl (%%"REG_c") , "tmp"                                     \n\t"\
100         "lea    -1("low")   , %%ecx                                     \n\t"\
101         "xor    "low"       , %%ecx                                     \n\t"\
102         "shr    $15         , %%ecx                                     \n\t"\
103         "bswap  "tmp"                                                   \n\t"\
104         "shr    $15         , "tmp"                                     \n\t"\
105         "movzbl "norm_off"("tables", %%rcx), %%ecx                      \n\t"\
106         "sub    $0xFFFF     , "tmp"                                     \n\t"\
107         "neg    %%ecx                                                   \n\t"\
108         "add    $7          , %%ecx                                     \n\t"\
109         "shl    %%cl        , "tmp"                                     \n\t"\
110         "add    "tmp"       , "low"                                     \n\t"\
111         "2:                                                             \n\t"
112
113 #else /* BROKEN_RELOCATIONS */
114 #define TABLES_ARG NAMED_CONSTRAINTS_ADD(ff_h264_cabac_tables)
115 #define RIP_ARG
116
117 #if HAVE_FAST_CMOV
118 #define BRANCHLESS_GET_CABAC_UPDATE(ret, low, range, tmp)\
119         "mov    "tmp"       , %%ecx     \n\t"\
120         "shl    $17         , "tmp"     \n\t"\
121         "cmp    "low"       , "tmp"     \n\t"\
122         "cmova  %%ecx       , "range"   \n\t"\
123         "sbb    %%ecx       , %%ecx     \n\t"\
124         "and    %%ecx       , "tmp"     \n\t"\
125         "xor    %%ecx       , "ret"     \n\t"\
126         "sub    "tmp"       , "low"     \n\t"
127 #else /* HAVE_FAST_CMOV */
128 #define BRANCHLESS_GET_CABAC_UPDATE(ret, low, range, tmp)\
129         "mov    "tmp"       , %%ecx     \n\t"\
130         "shl    $17         , "tmp"     \n\t"\
131         "sub    "low"       , "tmp"     \n\t"\
132         "sar    $31         , "tmp"     \n\t" /*lps_mask*/\
133         "sub    %%ecx       , "range"   \n\t" /*RangeLPS - range*/\
134         "and    "tmp"       , "range"   \n\t" /*(RangeLPS - range)&lps_mask*/\
135         "add    %%ecx       , "range"   \n\t" /*new range*/\
136         "shl    $17         , %%ecx     \n\t"\
137         "and    "tmp"       , %%ecx     \n\t"\
138         "sub    %%ecx       , "low"     \n\t"\
139         "xor    "tmp"       , "ret"     \n\t"
140 #endif /* HAVE_FAST_CMOV */
141
142 #define BRANCHLESS_GET_CABAC(ret, retq, statep, low, lowword, range, rangeq, tmp, tmpbyte, byte, end, norm_off, lps_off, mlps_off, tables) \
143         "movzbl "statep"    , "ret"                                     \n\t"\
144         "mov    "range"     , "tmp"                                     \n\t"\
145         "and    $0xC0       , "range"                                   \n\t"\
146         "movzbl "MANGLE(ff_h264_cabac_tables)"+"lps_off"("ret", "range", 2), "range" \n\t"\
147         "sub    "range"     , "tmp"                                     \n\t"\
148         BRANCHLESS_GET_CABAC_UPDATE(ret, low, range, tmp)                    \
149         "movzbl "MANGLE(ff_h264_cabac_tables)"+"norm_off"("range"), %%ecx    \n\t"\
150         "shl    %%cl        , "range"                                   \n\t"\
151         "movzbl "MANGLE(ff_h264_cabac_tables)"+"mlps_off"+128("ret"), "tmp"  \n\t"\
152         "shl    %%cl        , "low"                                     \n\t"\
153         "mov    "tmpbyte"   , "statep"                                  \n\t"\
154         "test   "lowword"   , "lowword"                                 \n\t"\
155         " jnz   2f                                                      \n\t"\
156         "mov    "byte"      , %%"REG_c"                                 \n\t"\
157         END_CHECK(end)\
158         "add"OPSIZE" $2     , "byte"                                    \n\t"\
159         "1:                                                             \n\t"\
160         "movzwl (%%"REG_c")     , "tmp"                                 \n\t"\
161         "lea    -1("low")   , %%ecx                                     \n\t"\
162         "xor    "low"       , %%ecx                                     \n\t"\
163         "shr    $15         , %%ecx                                     \n\t"\
164         "bswap  "tmp"                                                   \n\t"\
165         "shr    $15         , "tmp"                                     \n\t"\
166         "movzbl "MANGLE(ff_h264_cabac_tables)"+"norm_off"(%%ecx), %%ecx \n\t"\
167         "sub    $0xFFFF     , "tmp"                                     \n\t"\
168         "neg    %%ecx                                                   \n\t"\
169         "add    $7          , %%ecx                                     \n\t"\
170         "shl    %%cl        , "tmp"                                     \n\t"\
171         "add    "tmp"       , "low"                                     \n\t"\
172         "2:                                                             \n\t"
173
174 #endif /* BROKEN_RELOCATIONS */
175
176 #if HAVE_7REGS && !BROKEN_COMPILER
177 #define get_cabac_inline get_cabac_inline_x86
178 static av_always_inline int get_cabac_inline_x86(CABACContext *c,
179                                                  uint8_t *const state)
180 {
181     int bit, tmp;
182 #ifdef BROKEN_RELOCATIONS
183     void *tables;
184
185     __asm__ volatile(
186         "lea    "MANGLE(ff_h264_cabac_tables)", %0      \n\t"
187         : "=&r"(tables)
188         : NAMED_CONSTRAINTS(ff_h264_cabac_tables)
189     );
190 #endif
191
192     __asm__ volatile(
193         BRANCHLESS_GET_CABAC("%0", "%q0", "(%4)", "%1", "%w1",
194                              "%2", "%q2", "%3", "%b3",
195                              "%c6(%5)", "%c7(%5)",
196                              AV_STRINGIFY(H264_NORM_SHIFT_OFFSET),
197                              AV_STRINGIFY(H264_LPS_RANGE_OFFSET),
198                              AV_STRINGIFY(H264_MLPS_STATE_OFFSET),
199                              "%8")
200         : "=&r"(bit), "=&r"(c->low), "=&r"(c->range), "=&q"(tmp)
201         : "r"(state), "r"(c),
202           "i"(offsetof(CABACContext, bytestream)),
203           "i"(offsetof(CABACContext, bytestream_end))
204           TABLES_ARG
205           ,"1"(c->low), "2"(c->range)
206         : "%"REG_c, "memory"
207     );
208     return bit & 1;
209 }
210 #endif /* HAVE_7REGS && !BROKEN_COMPILER */
211
212 #if !BROKEN_COMPILER
213 #define get_cabac_bypass_sign get_cabac_bypass_sign_x86
214 static av_always_inline int get_cabac_bypass_sign_x86(CABACContext *c, int val)
215 {
216     x86_reg tmp;
217     __asm__ volatile(
218         "movl        %c6(%2), %k1       \n\t"
219         "movl        %c3(%2), %%eax     \n\t"
220         "shl             $17, %k1       \n\t"
221         "add           %%eax, %%eax     \n\t"
222         "sub             %k1, %%eax     \n\t"
223         "cdq                            \n\t"
224         "and           %%edx, %k1       \n\t"
225         "add             %k1, %%eax     \n\t"
226         "xor           %%edx, %%ecx     \n\t"
227         "sub           %%edx, %%ecx     \n\t"
228         "test           %%ax, %%ax      \n\t"
229         "jnz              1f            \n\t"
230         "mov         %c4(%2), %1        \n\t"
231         "subl        $0xFFFF, %%eax     \n\t"
232         "movzwl         (%1), %%edx     \n\t"
233         "bswap         %%edx            \n\t"
234         "shrl            $15, %%edx     \n\t"
235 #if UNCHECKED_BITSTREAM_READER
236         "add              $2, %1        \n\t"
237         "addl          %%edx, %%eax     \n\t"
238         "mov              %1, %c4(%2)   \n\t"
239 #else
240         "addl          %%edx, %%eax     \n\t"
241         "cmp         %c5(%2), %1        \n\t"
242         "jge              1f            \n\t"
243         "add"OPSIZE"      $2, %c4(%2)   \n\t"
244 #endif
245         "1:                             \n\t"
246         "movl          %%eax, %c3(%2)   \n\t"
247
248         : "+c"(val), "=&r"(tmp)
249         : "r"(c),
250           "i"(offsetof(CABACContext, low)),
251           "i"(offsetof(CABACContext, bytestream)),
252           "i"(offsetof(CABACContext, bytestream_end)),
253           "i"(offsetof(CABACContext, range))
254         : "%eax", "%edx", "memory"
255     );
256     return val;
257 }
258
259 #define get_cabac_bypass get_cabac_bypass_x86
260 static av_always_inline int get_cabac_bypass_x86(CABACContext *c)
261 {
262     x86_reg tmp;
263     int res;
264     __asm__ volatile(
265         "movl        %c6(%2), %k1       \n\t"
266         "movl        %c3(%2), %%eax     \n\t"
267         "shl             $17, %k1       \n\t"
268         "add           %%eax, %%eax     \n\t"
269         "sub             %k1, %%eax     \n\t"
270         "cdq                            \n\t"
271         "and           %%edx, %k1       \n\t"
272         "add             %k1, %%eax     \n\t"
273         "inc           %%edx            \n\t"
274         "test           %%ax, %%ax      \n\t"
275         "jnz              1f            \n\t"
276         "mov         %c4(%2), %1        \n\t"
277         "subl        $0xFFFF, %%eax     \n\t"
278         "movzwl         (%1), %%ecx     \n\t"
279         "bswap         %%ecx            \n\t"
280         "shrl            $15, %%ecx     \n\t"
281         "addl          %%ecx, %%eax     \n\t"
282         "cmp         %c5(%2), %1        \n\t"
283         "jge              1f            \n\t"
284         "add"OPSIZE"      $2, %c4(%2)   \n\t"
285         "1:                             \n\t"
286         "movl          %%eax, %c3(%2)   \n\t"
287
288         : "=&d"(res), "=&r"(tmp)
289         : "r"(c),
290           "i"(offsetof(CABACContext, low)),
291           "i"(offsetof(CABACContext, bytestream)),
292           "i"(offsetof(CABACContext, bytestream_end)),
293           "i"(offsetof(CABACContext, range))
294         : "%eax", "%ecx", "memory"
295     );
296     return res;
297 }
298 #endif /* !BROKEN_COMPILER */
299
300 #endif /* HAVE_INLINE_ASM */
301 #endif /* AVCODEC_X86_CABAC_H */