FFmpeg coverage


Directory: ../../../ffmpeg/
File: src/libavcodec/x86/cabac.h
Date: 2021-09-24 20:55:06
Exec Total Coverage
Lines: 11 11 100.0%
Branches: 0 0 -%

Line Branch Exec Source
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(__i386) && defined(__clang__) && (__clang_major__<2 || (__clang_major__==2 && __clang_minor__<10)))\
33 || ( !defined(__clang__) && defined(__llvm__) && __GNUC__==4 && __GNUC_MINOR__==2 && __GNUC_PATCHLEVEL__<=1)\
34 || (defined(__INTEL_COMPILER) && defined(_MSC_VER))
35 # define BROKEN_COMPILER 1
36 #else
37 # define BROKEN_COMPILER 0
38 #endif
39
40 #if HAVE_INLINE_ASM
41
42 #ifndef UNCHECKED_BITSTREAM_READER
43 #define UNCHECKED_BITSTREAM_READER !CONFIG_SAFE_BITSTREAM_READER
44 #endif
45
46 #if UNCHECKED_BITSTREAM_READER
47 #define END_CHECK(end) ""
48 #else
49 #define END_CHECK(end) \
50 "cmp "end" , %%"FF_REG_c" \n\t"\
51 "jge 1f \n\t"
52 #endif
53
54 #ifdef BROKEN_RELOCATIONS
55 #define TABLES_ARG , "r"(tables)
56
57 #if HAVE_FAST_CMOV
58 #define BRANCHLESS_GET_CABAC_UPDATE(ret, retq, low, range, tmp) \
59 "cmp "low" , "tmp" \n\t"\
60 "cmova %%ecx , "range" \n\t"\
61 "sbb %%rcx , %%rcx \n\t"\
62 "and %%ecx , "tmp" \n\t"\
63 "xor %%rcx , "retq" \n\t"\
64 "sub "tmp" , "low" \n\t"
65 #else /* HAVE_FAST_CMOV */
66 #define BRANCHLESS_GET_CABAC_UPDATE(ret, retq, low, range, tmp) \
67 /* P4 Prescott has crappy cmov,sbb,64-bit shift so avoid them */ \
68 "sub "low" , "tmp" \n\t"\
69 "sar $31 , "tmp" \n\t"\
70 "sub %%ecx , "range" \n\t"\
71 "and "tmp" , "range" \n\t"\
72 "add %%ecx , "range" \n\t"\
73 "shl $17 , %%ecx \n\t"\
74 "and "tmp" , %%ecx \n\t"\
75 "sub %%ecx , "low" \n\t"\
76 "xor "tmp" , "ret" \n\t"\
77 "movslq "ret" , "retq" \n\t"
78 #endif /* HAVE_FAST_CMOV */
79
80 #define BRANCHLESS_GET_CABAC(ret, retq, statep, low, lowword, range, rangeq, tmp, tmpbyte, byte, end, norm_off, lps_off, mlps_off, tables) \
81 "movzbl "statep" , "ret" \n\t"\
82 "mov "range" , "tmp" \n\t"\
83 "and $0xC0 , "range" \n\t"\
84 "lea ("ret", "range", 2), %%ecx \n\t"\
85 "movzbl "lps_off"("tables", %%rcx), "range" \n\t"\
86 "sub "range" , "tmp" \n\t"\
87 "mov "tmp" , %%ecx \n\t"\
88 "shl $17 , "tmp" \n\t"\
89 BRANCHLESS_GET_CABAC_UPDATE(ret, retq, low, range, tmp) \
90 "movzbl "norm_off"("tables", "rangeq"), %%ecx \n\t"\
91 "shl %%cl , "range" \n\t"\
92 "movzbl "mlps_off"+128("tables", "retq"), "tmp" \n\t"\
93 "shl %%cl , "low" \n\t"\
94 "mov "tmpbyte" , "statep" \n\t"\
95 "test "lowword" , "lowword" \n\t"\
96 "jnz 2f \n\t"\
97 "mov "byte" , %%"FF_REG_c" \n\t"\
98 END_CHECK(end)\
99 "add"FF_OPSIZE" $2 , "byte" \n\t"\
100 "1: \n\t"\
101 "movzwl (%%"FF_REG_c") , "tmp" \n\t"\
102 "lea -1("low") , %%ecx \n\t"\
103 "xor "low" , %%ecx \n\t"\
104 "shr $15 , %%ecx \n\t"\
105 "bswap "tmp" \n\t"\
106 "shr $15 , "tmp" \n\t"\
107 "movzbl "norm_off"("tables", %%rcx), %%ecx \n\t"\
108 "sub $0xFFFF , "tmp" \n\t"\
109 "neg %%ecx \n\t"\
110 "add $7 , %%ecx \n\t"\
111 "shl %%cl , "tmp" \n\t"\
112 "add "tmp" , "low" \n\t"\
113 "2: \n\t"
114
115 #else /* BROKEN_RELOCATIONS */
116 #define TABLES_ARG NAMED_CONSTRAINTS_ARRAY_ADD(ff_h264_cabac_tables)
117 #define RIP_ARG
118
119 #if HAVE_FAST_CMOV
120 #define BRANCHLESS_GET_CABAC_UPDATE(ret, low, range, tmp)\
121 "mov "tmp" , %%ecx \n\t"\
122 "shl $17 , "tmp" \n\t"\
123 "cmp "low" , "tmp" \n\t"\
124 "cmova %%ecx , "range" \n\t"\
125 "sbb %%ecx , %%ecx \n\t"\
126 "and %%ecx , "tmp" \n\t"\
127 "xor %%ecx , "ret" \n\t"\
128 "sub "tmp" , "low" \n\t"
129 #else /* HAVE_FAST_CMOV */
130 #define BRANCHLESS_GET_CABAC_UPDATE(ret, low, range, tmp)\
131 "mov "tmp" , %%ecx \n\t"\
132 "shl $17 , "tmp" \n\t"\
133 "sub "low" , "tmp" \n\t"\
134 "sar $31 , "tmp" \n\t" /*lps_mask*/\
135 "sub %%ecx , "range" \n\t" /*RangeLPS - range*/\
136 "and "tmp" , "range" \n\t" /*(RangeLPS - range)&lps_mask*/\
137 "add %%ecx , "range" \n\t" /*new range*/\
138 "shl $17 , %%ecx \n\t"\
139 "and "tmp" , %%ecx \n\t"\
140 "sub %%ecx , "low" \n\t"\
141 "xor "tmp" , "ret" \n\t"
142 #endif /* HAVE_FAST_CMOV */
143
144 #define BRANCHLESS_GET_CABAC(ret, retq, statep, low, lowword, range, rangeq, tmp, tmpbyte, byte, end, norm_off, lps_off, mlps_off, tables) \
145 "movzbl "statep" , "ret" \n\t"\
146 "mov "range" , "tmp" \n\t"\
147 "and $0xC0 , "range" \n\t"\
148 "movzbl "MANGLE(ff_h264_cabac_tables)"+"lps_off"("ret", "range", 2), "range" \n\t"\
149 "sub "range" , "tmp" \n\t"\
150 BRANCHLESS_GET_CABAC_UPDATE(ret, low, range, tmp) \
151 "movzbl "MANGLE(ff_h264_cabac_tables)"+"norm_off"("range"), %%ecx \n\t"\
152 "shl %%cl , "range" \n\t"\
153 "movzbl "MANGLE(ff_h264_cabac_tables)"+"mlps_off"+128("ret"), "tmp" \n\t"\
154 "shl %%cl , "low" \n\t"\
155 "mov "tmpbyte" , "statep" \n\t"\
156 "test "lowword" , "lowword" \n\t"\
157 " jnz 2f \n\t"\
158 "mov "byte" , %%"FF_REG_c" \n\t"\
159 END_CHECK(end)\
160 "add"FF_OPSIZE" $2 , "byte" \n\t"\
161 "1: \n\t"\
162 "movzwl (%%"FF_REG_c") , "tmp" \n\t"\
163 "lea -1("low") , %%ecx \n\t"\
164 "xor "low" , %%ecx \n\t"\
165 "shr $15 , %%ecx \n\t"\
166 "bswap "tmp" \n\t"\
167 "shr $15 , "tmp" \n\t"\
168 "movzbl "MANGLE(ff_h264_cabac_tables)"+"norm_off"(%%ecx), %%ecx \n\t"\
169 "sub $0xFFFF , "tmp" \n\t"\
170 "neg %%ecx \n\t"\
171 "add $7 , %%ecx \n\t"\
172 "shl %%cl , "tmp" \n\t"\
173 "add "tmp" , "low" \n\t"\
174 "2: \n\t"
175
176 #endif /* BROKEN_RELOCATIONS */
177
178 #if HAVE_7REGS && !BROKEN_COMPILER
179 #define get_cabac_inline get_cabac_inline_x86
180 static
181 #if defined(_WIN32) && !defined(_WIN64) && defined(__clang__)
182 av_noinline
183 #else
184 av_always_inline
185 #endif
186 1080131523 int get_cabac_inline_x86(CABACContext *c, uint8_t *const state)
187 {
188 int bit, tmp;
189 #ifdef BROKEN_RELOCATIONS
190 void *tables;
191
192 1080131523 __asm__ volatile(
193 "lea "MANGLE(ff_h264_cabac_tables)", %0 \n\t"
194 : "=&r"(tables)
195 : NAMED_CONSTRAINTS_ARRAY(ff_h264_cabac_tables)
196 );
197 #endif
198
199 1080131523 __asm__ volatile(
200 BRANCHLESS_GET_CABAC("%0", "%q0", "(%4)", "%1", "%w1",
201 "%2", "%q2", "%3", "%b3",
202 "%c6(%5)", "%c7(%5)",
203 AV_STRINGIFY(H264_NORM_SHIFT_OFFSET),
204 AV_STRINGIFY(H264_LPS_RANGE_OFFSET),
205 AV_STRINGIFY(H264_MLPS_STATE_OFFSET),
206 "%8")
207 : "=&r"(bit), "=&r"(c->low), "=&r"(c->range), "=&q"(tmp)
208 : "r"(state), "r"(c),
209 "i"(offsetof(CABACContext, bytestream)),
210 "i"(offsetof(CABACContext, bytestream_end))
211 TABLES_ARG
212 1080131523 ,"1"(c->low), "2"(c->range)
213 : "%"FF_REG_c, "memory"
214 );
215 1080131523 return bit & 1;
216 }
217 #endif /* HAVE_7REGS && !BROKEN_COMPILER */
218
219 #if !BROKEN_COMPILER
220 #define get_cabac_bypass_sign get_cabac_bypass_sign_x86
221 173828250 static av_always_inline int get_cabac_bypass_sign_x86(CABACContext *c, int val)
222 {
223 x86_reg tmp;
224 173828250 __asm__ volatile(
225 "movl %c6(%2), %k1 \n\t"
226 "movl %c3(%2), %%eax \n\t"
227 "shl $17, %k1 \n\t"
228 "add %%eax, %%eax \n\t"
229 "sub %k1, %%eax \n\t"
230 "cdq \n\t"
231 "and %%edx, %k1 \n\t"
232 "add %k1, %%eax \n\t"
233 "xor %%edx, %%ecx \n\t"
234 "sub %%edx, %%ecx \n\t"
235 "test %%ax, %%ax \n\t"
236 "jnz 1f \n\t"
237 "mov %c4(%2), %1 \n\t"
238 "subl $0xFFFF, %%eax \n\t"
239 "movzwl (%1), %%edx \n\t"
240 "bswap %%edx \n\t"
241 "shrl $15, %%edx \n\t"
242 #if UNCHECKED_BITSTREAM_READER
243 "add $2, %1 \n\t"
244 "addl %%edx, %%eax \n\t"
245 "mov %1, %c4(%2) \n\t"
246 #else
247 "addl %%edx, %%eax \n\t"
248 "cmp %c5(%2), %1 \n\t"
249 "jge 1f \n\t"
250 "add"FF_OPSIZE" $2, %c4(%2) \n\t"
251 #endif
252 "1: \n\t"
253 "movl %%eax, %c3(%2) \n\t"
254
255 : "+c"(val), "=&r"(tmp)
256 : "r"(c),
257 "i"(offsetof(CABACContext, low)),
258 "i"(offsetof(CABACContext, bytestream)),
259 "i"(offsetof(CABACContext, bytestream_end)),
260 "i"(offsetof(CABACContext, range))
261 : "%eax", "%edx", "memory"
262 );
263 173828250 return val;
264 }
265
266 #define get_cabac_bypass get_cabac_bypass_x86
267 330856301 static av_always_inline int get_cabac_bypass_x86(CABACContext *c)
268 {
269 x86_reg tmp;
270 int res;
271 330856301 __asm__ volatile(
272 "movl %c6(%2), %k1 \n\t"
273 "movl %c3(%2), %%eax \n\t"
274 "shl $17, %k1 \n\t"
275 "add %%eax, %%eax \n\t"
276 "sub %k1, %%eax \n\t"
277 "cdq \n\t"
278 "and %%edx, %k1 \n\t"
279 "add %k1, %%eax \n\t"
280 "inc %%edx \n\t"
281 "test %%ax, %%ax \n\t"
282 "jnz 1f \n\t"
283 "mov %c4(%2), %1 \n\t"
284 "subl $0xFFFF, %%eax \n\t"
285 "movzwl (%1), %%ecx \n\t"
286 "bswap %%ecx \n\t"
287 "shrl $15, %%ecx \n\t"
288 "addl %%ecx, %%eax \n\t"
289 "cmp %c5(%2), %1 \n\t"
290 "jge 1f \n\t"
291 "add"FF_OPSIZE" $2, %c4(%2) \n\t"
292 "1: \n\t"
293 "movl %%eax, %c3(%2) \n\t"
294
295 : "=&d"(res), "=&r"(tmp)
296 : "r"(c),
297 "i"(offsetof(CABACContext, low)),
298 "i"(offsetof(CABACContext, bytestream)),
299 "i"(offsetof(CABACContext, bytestream_end)),
300 "i"(offsetof(CABACContext, range))
301 : "%eax", "%ecx", "memory"
302 );
303 330856301 return res;
304 }
305 #endif /* !BROKEN_COMPILER */
306
307 #endif /* HAVE_INLINE_ASM */
308 #endif /* AVCODEC_X86_CABAC_H */
309