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cabac.h
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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 <stddef.h>
25
26#include "libavcodec/cabac.h"
27#include "libavutil/attributes.h"
28#include "libavutil/macros.h"
29#include "libavutil/x86/asm.h"
30#include "config.h"
31
32#if 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" , %%"FF_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,64-bit 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#ifdef __LZCNT__
79/* renormalisation shift = lzcnt(range) - 23, refill shift = tzcnt(low) - 16 */
80#define BRANCHLESS_GET_CABAC_RENORM(range, rangeq, norm_off, tables) \
81 "lzcnt "range" , %%ecx \n\t"\
82 "sub $23 , %%ecx \n\t"
83#define BRANCHLESS_GET_CABAC_REFILL(low, tmp, norm_off, tables) \
84 "movzwl (%%"FF_REG_c") , "tmp" \n\t"\
85 "tzcnt "low" , %%ecx \n\t"\
86 "bswap "tmp" \n\t"\
87 "shr $15 , "tmp" \n\t"\
88 "sub $16 , %%ecx \n\t"\
89 "sub $0xFFFF , "tmp" \n\t"\
90 "shl %%cl , "tmp" \n\t"\
91 "add "tmp" , "low" \n\t"
92#else /* __LZCNT__ */
93#define BRANCHLESS_GET_CABAC_RENORM(range, rangeq, norm_off, tables) \
94 "movzbl "norm_off"("tables", "rangeq"), %%ecx \n\t"
95#define BRANCHLESS_GET_CABAC_REFILL(low, tmp, norm_off, tables) \
96 "movzwl (%%"FF_REG_c") , "tmp" \n\t"\
97 "lea -1("low") , %%ecx \n\t"\
98 "xor "low" , %%ecx \n\t"\
99 "shr $15 , %%ecx \n\t"\
100 "bswap "tmp" \n\t"\
101 "shr $15 , "tmp" \n\t"\
102 "movzbl "norm_off"("tables", %%rcx), %%ecx \n\t"\
103 "sub $0xFFFF , "tmp" \n\t"\
104 "neg %%ecx \n\t"\
105 "add $7 , %%ecx \n\t"\
106 "shl %%cl , "tmp" \n\t"\
107 "add "tmp" , "low" \n\t"
108#endif /* __LZCNT__ */
109
110#define BRANCHLESS_GET_CABAC(ret, retq, statep, low, lowword, range, rangeq, tmp, tmpbyte, byte, end, norm_off, lps_off, mlps_off, tables) \
111 "movzbl "statep" , "ret" \n\t"\
112 "mov "range" , "tmp" \n\t"\
113 "and $0xC0 , "range" \n\t"\
114 "lea ("ret", "range", 2), %%ecx \n\t"\
115 "movzbl "lps_off"("tables", %%rcx), "range" \n\t"\
116 "sub "range" , "tmp" \n\t"\
117 "mov "tmp" , %%ecx \n\t"\
118 "shl $17 , "tmp" \n\t"\
119 BRANCHLESS_GET_CABAC_UPDATE(ret, retq, low, range, tmp) \
120 BRANCHLESS_GET_CABAC_RENORM(range, rangeq, norm_off, tables) \
121 "shl %%cl , "range" \n\t"\
122 "movzbl "mlps_off"+128("tables", "retq"), "tmp" \n\t"\
123 "shl %%cl , "low" \n\t"\
124 "mov "tmpbyte" , "statep" \n\t"\
125 "test "lowword" , "lowword" \n\t"\
126 "jnz 2f \n\t"\
127 "mov "byte" , %%"FF_REG_c" \n\t"\
128 END_CHECK(end)\
129 "add"FF_OPSIZE" $2 , "byte" \n\t"\
130 "1: \n\t"\
131 BRANCHLESS_GET_CABAC_REFILL(low, tmp, norm_off, tables) \
132 "2: \n\t"
133
134#else /* BROKEN_RELOCATIONS */
135#define TABLES_ARG NAMED_CONSTRAINTS_ARRAY_ADD(ff_h264_cabac_tables)
136#define RIP_ARG
137
138#if HAVE_FAST_CMOV
139#define BRANCHLESS_GET_CABAC_UPDATE(ret, low, range, tmp)\
140 "mov "tmp" , %%ecx \n\t"\
141 "shl $17 , "tmp" \n\t"\
142 "cmp "low" , "tmp" \n\t"\
143 "cmova %%ecx , "range" \n\t"\
144 "sbb %%ecx , %%ecx \n\t"\
145 "and %%ecx , "tmp" \n\t"\
146 "xor %%ecx , "ret" \n\t"\
147 "sub "tmp" , "low" \n\t"
148#else /* HAVE_FAST_CMOV */
149#define BRANCHLESS_GET_CABAC_UPDATE(ret, low, range, tmp)\
150 "mov "tmp" , %%ecx \n\t"\
151 "shl $17 , "tmp" \n\t"\
152 "sub "low" , "tmp" \n\t"\
153 "sar $31 , "tmp" \n\t" /*lps_mask*/\
154 "sub %%ecx , "range" \n\t" /*RangeLPS - range*/\
155 "and "tmp" , "range" \n\t" /*(RangeLPS - range)&lps_mask*/\
156 "add %%ecx , "range" \n\t" /*new range*/\
157 "shl $17 , %%ecx \n\t"\
158 "and "tmp" , %%ecx \n\t"\
159 "sub %%ecx , "low" \n\t"\
160 "xor "tmp" , "ret" \n\t"
161#endif /* HAVE_FAST_CMOV */
162
163#ifdef __LZCNT__
164#define BRANCHLESS_GET_CABAC_RENORM(range, rangeq, norm_off, tables) \
165 "lzcnt "range" , %%ecx \n\t"\
166 "sub $23 , %%ecx \n\t"
167#define BRANCHLESS_GET_CABAC_REFILL(low, tmp, norm_off, tables) \
168 "movzwl (%%"FF_REG_c") , "tmp" \n\t"\
169 "tzcnt "low" , %%ecx \n\t"\
170 "bswap "tmp" \n\t"\
171 "shr $15 , "tmp" \n\t"\
172 "sub $16 , %%ecx \n\t"\
173 "sub $0xFFFF , "tmp" \n\t"\
174 "shl %%cl , "tmp" \n\t"\
175 "add "tmp" , "low" \n\t"
176#else /* __LZCNT__ */
177#define BRANCHLESS_GET_CABAC_RENORM(range, rangeq, norm_off, tables) \
178 "movzbl "MANGLE(ff_h264_cabac_tables)"+"norm_off"("range"), %%ecx \n\t"
179#define BRANCHLESS_GET_CABAC_REFILL(low, tmp, norm_off, tables) \
180 "movzwl (%%"FF_REG_c") , "tmp" \n\t"\
181 "lea -1("low") , %%ecx \n\t"\
182 "xor "low" , %%ecx \n\t"\
183 "shr $15 , %%ecx \n\t"\
184 "bswap "tmp" \n\t"\
185 "shr $15 , "tmp" \n\t"\
186 "movzbl "MANGLE(ff_h264_cabac_tables)"+"norm_off"(%%ecx), %%ecx \n\t"\
187 "sub $0xFFFF , "tmp" \n\t"\
188 "neg %%ecx \n\t"\
189 "add $7 , %%ecx \n\t"\
190 "shl %%cl , "tmp" \n\t"\
191 "add "tmp" , "low" \n\t"
192#endif /* __LZCNT__ */
193
194#define BRANCHLESS_GET_CABAC(ret, retq, statep, low, lowword, range, rangeq, tmp, tmpbyte, byte, end, norm_off, lps_off, mlps_off, tables) \
195 "movzbl "statep" , "ret" \n\t"\
196 "mov "range" , "tmp" \n\t"\
197 "and $0xC0 , "range" \n\t"\
198 "movzbl "MANGLE(ff_h264_cabac_tables)"+"lps_off"("ret", "range", 2), "range" \n\t"\
199 "sub "range" , "tmp" \n\t"\
200 BRANCHLESS_GET_CABAC_UPDATE(ret, low, range, tmp) \
201 BRANCHLESS_GET_CABAC_RENORM(range, rangeq, norm_off, tables) \
202 "shl %%cl , "range" \n\t"\
203 "movzbl "MANGLE(ff_h264_cabac_tables)"+"mlps_off"+128("ret"), "tmp" \n\t"\
204 "shl %%cl , "low" \n\t"\
205 "mov "tmpbyte" , "statep" \n\t"\
206 "test "lowword" , "lowword" \n\t"\
207 " jnz 2f \n\t"\
208 "mov "byte" , %%"FF_REG_c" \n\t"\
209 END_CHECK(end)\
210 "add"FF_OPSIZE" $2 , "byte" \n\t"\
211 "1: \n\t"\
212 BRANCHLESS_GET_CABAC_REFILL(low, tmp, norm_off, tables) \
213 "2: \n\t"
214
215#endif /* BROKEN_RELOCATIONS */
216
217#if HAVE_X86_7REGS && !BROKEN_COMPILER
218#define get_cabac_inline get_cabac_inline_x86
219static
220#if ARCH_X86_32
221av_noinline
222#else
223av_always_inline
224#endif
225int get_cabac_inline_x86(CABACContext *c, uint8_t *const state)
226{
227 int bit, tmp;
228#ifdef BROKEN_RELOCATIONS
229 void *tables;
230
231 __asm__ volatile(
232 "lea "MANGLE(ff_h264_cabac_tables)", %0 \n\t"
233 : "=&r"(tables)
234 : NAMED_CONSTRAINTS_ARRAY(ff_h264_cabac_tables)
235 );
236#endif
237
238 __asm__ volatile(
239 BRANCHLESS_GET_CABAC("%0", "%q0", "(%4)", "%1", "%w1",
240 "%2", "%q2", "%3", "%b3",
241 "%c6(%5)", "%c7(%5)",
242 AV_STRINGIFY(H264_NORM_SHIFT_OFFSET),
243 AV_STRINGIFY(H264_LPS_RANGE_OFFSET),
244 AV_STRINGIFY(H264_MLPS_STATE_OFFSET),
245 "%8")
246 : "=&r"(bit), "=&r"(c->low), "=&r"(c->range), "=&q"(tmp)
247 : "r"(state), "r"(c),
248 "i"(offsetof(CABACContext, bytestream)),
249 "i"(offsetof(CABACContext, bytestream_end))
250 TABLES_ARG
251 ,"1"(c->low), "2"(c->range)
252 : "%"FF_REG_c, "memory"
253 );
254 return bit & 1;
255}
256#endif /* HAVE_X86_7REGS && !BROKEN_COMPILER */
257
258#if !BROKEN_COMPILER
259#define get_cabac_bypass_sign get_cabac_bypass_sign_x86
260static av_always_inline int get_cabac_bypass_sign_x86(CABACContext *c, int val)
261{
262 x86_reg tmp;
263 __asm__ volatile(
264 "movl %c6(%2), %k1 \n\t"
265 "movl %c3(%2), %%eax \n\t"
266 "shl $17, %k1 \n\t"
267 "add %%eax, %%eax \n\t"
268 "sub %k1, %%eax \n\t"
269 "cdq \n\t"
270 "and %%edx, %k1 \n\t"
271 "add %k1, %%eax \n\t"
272 "xor %%edx, %%ecx \n\t"
273 "sub %%edx, %%ecx \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), %%edx \n\t"
279 "bswap %%edx \n\t"
280 "shrl $15, %%edx \n\t"
281#if UNCHECKED_BITSTREAM_READER
282 "add $2, %1 \n\t"
283 "addl %%edx, %%eax \n\t"
284 "mov %1, %c4(%2) \n\t"
285#else
286 "addl %%edx, %%eax \n\t"
287 "cmp %c5(%2), %1 \n\t"
288 "jge 1f \n\t"
289 "add"FF_OPSIZE" $2, %c4(%2) \n\t"
290#endif
291 "1: \n\t"
292 "movl %%eax, %c3(%2) \n\t"
293
294 : "+c"(val), "=&r"(tmp)
295 : "r"(c),
296 "i"(offsetof(CABACContext, low)),
297 "i"(offsetof(CABACContext, bytestream)),
298 "i"(offsetof(CABACContext, bytestream_end)),
299 "i"(offsetof(CABACContext, range))
300 : "%eax", "%edx", "memory"
301 );
302 return val;
303}
304
305#define get_cabac_bypass get_cabac_bypass_x86
306static av_always_inline int get_cabac_bypass_x86(CABACContext *c)
307{
308 x86_reg tmp;
309 int res;
310 __asm__ volatile(
311 "movl %c6(%2), %k1 \n\t"
312 "movl %c3(%2), %%eax \n\t"
313 "shl $17, %k1 \n\t"
314 "add %%eax, %%eax \n\t"
315 "sub %k1, %%eax \n\t"
316 "cdq \n\t"
317 "and %%edx, %k1 \n\t"
318 "add %k1, %%eax \n\t"
319 "inc %%edx \n\t"
320 "test %%ax, %%ax \n\t"
321 "jnz 1f \n\t"
322 "mov %c4(%2), %1 \n\t"
323 "subl $0xFFFF, %%eax \n\t"
324 "movzwl (%1), %%ecx \n\t"
325 "bswap %%ecx \n\t"
326 "shrl $15, %%ecx \n\t"
327 "addl %%ecx, %%eax \n\t"
328 "cmp %c5(%2), %1 \n\t"
329 "jge 1f \n\t"
330 "add"FF_OPSIZE" $2, %c4(%2) \n\t"
331 "1: \n\t"
332 "movl %%eax, %c3(%2) \n\t"
333
334 : "=&d"(res), "=&r"(tmp)
335 : "r"(c),
336 "i"(offsetof(CABACContext, low)),
337 "i"(offsetof(CABACContext, bytestream)),
338 "i"(offsetof(CABACContext, bytestream_end)),
339 "i"(offsetof(CABACContext, range))
340 : "%eax", "%ecx", "memory"
341 );
342 return res;
343}
344#endif /* !BROKEN_COMPILER */
345
346#endif /* HAVE_INLINE_ASM */
347#endif /* AVCODEC_X86_CABAC_H */
val
static double val(void *priv, double ch)
Definition aeval.c:77
NAMED_CONSTRAINTS_ARRAY
#define NAMED_CONSTRAINTS_ARRAY(...)
Definition asm.h:147
MANGLE
#define MANGLE(a)
Definition asm.h:123
x86_reg
int x86_reg
Definition asm.h:71
__asm__
__asm__(".macro parse_r var r\n\t" "\\var = -1\n\t" _IFC_REG(0) _IFC_REG(1) _IFC_REG(2) _IFC_REG(3) _IFC_REG(4) _IFC_REG(5) _IFC_REG(6) _IFC_REG(7) _IFC_REG(8) _IFC_REG(9) _IFC_REG(10) _IFC_REG(11) _IFC_REG(12) _IFC_REG(13) _IFC_REG(14) _IFC_REG(15) _IFC_REG(16) _IFC_REG(17) _IFC_REG(18) _IFC_REG(19) _IFC_REG(20) _IFC_REG(21) _IFC_REG(22) _IFC_REG(23) _IFC_REG(24) _IFC_REG(25) _IFC_REG(26) _IFC_REG(27) _IFC_REG(28) _IFC_REG(29) _IFC_REG(30) _IFC_REG(31) ".iflt \\var\n\t" ".error \"Unable to parse register name \\r\"\n\t" ".endif\n\t" ".endm")
cabac.h
Context Adaptive Binary Arithmetic Coder.
H264_LPS_RANGE_OFFSET
#define H264_LPS_RANGE_OFFSET
Definition cabac.h:34
H264_MLPS_STATE_OFFSET
#define H264_MLPS_STATE_OFFSET
Definition cabac.h:35
H264_NORM_SHIFT_OFFSET
#define H264_NORM_SHIFT_OFFSET
Definition cabac.h:33
ff_h264_cabac_tables
const uint8_t ff_h264_cabac_tables[512+4 *2 *64+4 *64+63]
bit
#define bit(string, value)
Definition cbs_mpeg2.c:56
state
static struct @346255127015250356166251341105367306144006377143 state
AV_STRINGIFY
#define AV_STRINGIFY(s)
Definition macros.h:66
attributes.h
Macro definitions for various function/variable attributes.
av_always_inline
#define av_always_inline
Definition attributes.h:72
av_noinline
#define av_noinline
Definition attributes.h:97
macros.h
Utility Preprocessor macros.
range
enum AVColorRange range
Definition mediacodec_wrapper.c:2694
tmp
static uint8_t tmp[40]
Definition aes_ctr.c:52
tables
static const uint8_t *const tables[]
Definition truemotion1data.h:830
c
static double c[64]
Definition vsrc_mptestsrc.c:89
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