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h264_i386.h
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1 /*
2  * H.26L/H.264/AVC/JVT/14496-10/... encoder/decoder
3  * Copyright (c) 2003 Michael Niedermayer <michaelni@gmx.at>
4  *
5  * This file is part of FFmpeg.
6  *
7  * FFmpeg is free software; you can redistribute it and/or
8  * modify it under the terms of the GNU Lesser General Public
9  * License as published by the Free Software Foundation; either
10  * version 2.1 of the License, or (at your option) any later version.
11  *
12  * FFmpeg is distributed in the hope that it will be useful,
13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15  * Lesser General Public License for more details.
16  *
17  * You should have received a copy of the GNU Lesser General Public
18  * License along with FFmpeg; if not, write to the Free Software
19  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
20  */
21 
22 /**
23  * @file
24  * H.264 / AVC / MPEG4 part10 codec.
25  * non-MMX i386-specific optimizations for H.264
26  * @author Michael Niedermayer <michaelni@gmx.at>
27  */
28 
29 #ifndef AVCODEC_X86_H264_I386_H
30 #define AVCODEC_X86_H264_I386_H
31 
32 #include <stddef.h>
33 
34 #include "libavcodec/cabac.h"
35 #include "cabac.h"
36 
37 #if HAVE_INLINE_ASM
38 
39 #if ARCH_X86_64
40 #define REG64 "r"
41 #else
42 #define REG64 "m"
43 #endif
44 
45 //FIXME use some macros to avoid duplicating get_cabac (cannot be done yet
46 //as that would make optimization work hard)
47 #if HAVE_7REGS && !BROKEN_COMPILER
48 #define decode_significance decode_significance_x86
49 static int decode_significance_x86(CABACContext *c, int max_coeff,
50  uint8_t *significant_coeff_ctx_base,
51  int *index, x86_reg last_off){
52  void *end= significant_coeff_ctx_base + max_coeff - 1;
53  int minusstart= -(intptr_t)significant_coeff_ctx_base;
54  int minusindex= 4-(intptr_t)index;
55  int bit;
56  x86_reg coeff_count;
57 
58 #ifdef BROKEN_RELOCATIONS
59  void *tables;
60 
61  __asm__ volatile(
62  "lea "MANGLE(ff_h264_cabac_tables)", %0 \n\t"
63  : "=&r"(tables)
65  );
66 #endif
67 
68  __asm__ volatile(
69  "3: \n\t"
70 
71  BRANCHLESS_GET_CABAC("%4", "%q4", "(%1)", "%3", "%w3",
72  "%5", "%q5", "%k0", "%b0",
73  "%c11(%6)", "%c12(%6)",
77  "%13")
78 
79  "test $1, %4 \n\t"
80  " jz 4f \n\t"
81  "add %10, %1 \n\t"
82 
83  BRANCHLESS_GET_CABAC("%4", "%q4", "(%1)", "%3", "%w3",
84  "%5", "%q5", "%k0", "%b0",
85  "%c11(%6)", "%c12(%6)",
89  "%13")
90 
91  "sub %10, %1 \n\t"
92  "mov %2, %0 \n\t"
93  "movl %7, %%ecx \n\t"
94  "add %1, %%"REG_c" \n\t"
95  "movl %%ecx, (%0) \n\t"
96 
97  "test $1, %4 \n\t"
98  " jnz 5f \n\t"
99 
100  "add"OPSIZE" $4, %2 \n\t"
101 
102  "4: \n\t"
103  "add $1, %1 \n\t"
104  "cmp %8, %1 \n\t"
105  " jb 3b \n\t"
106  "mov %2, %0 \n\t"
107  "movl %7, %%ecx \n\t"
108  "add %1, %%"REG_c" \n\t"
109  "movl %%ecx, (%0) \n\t"
110  "5: \n\t"
111  "add %9, %k0 \n\t"
112  "shr $2, %k0 \n\t"
113  : "=&q"(coeff_count), "+r"(significant_coeff_ctx_base), "+m"(index),
114  "+&r"(c->low), "=&r"(bit), "+&r"(c->range)
115  : "r"(c), "m"(minusstart), "m"(end), "m"(minusindex), "m"(last_off),
116  "i"(offsetof(CABACContext, bytestream)),
117  "i"(offsetof(CABACContext, bytestream_end))
118  TABLES_ARG
119  : "%"REG_c, "memory"
120  );
121  return coeff_count;
122 }
123 
124 #define decode_significance_8x8 decode_significance_8x8_x86
125 static int decode_significance_8x8_x86(CABACContext *c,
126  uint8_t *significant_coeff_ctx_base,
127  int *index, uint8_t *last_coeff_ctx_base, const uint8_t *sig_off){
128  int minusindex= 4-(intptr_t)index;
129  int bit;
130  x86_reg coeff_count;
131  x86_reg last=0;
132  x86_reg state;
133 
134 #ifdef BROKEN_RELOCATIONS
135  void *tables;
136 
137  __asm__ volatile(
138  "lea "MANGLE(ff_h264_cabac_tables)", %0 \n\t"
139  : "=&r"(tables)
141  );
142 #endif
143 
144  __asm__ volatile(
145  "mov %1, %6 \n\t"
146  "3: \n\t"
147 
148  "mov %10, %0 \n\t"
149  "movzb (%0, %6), %6 \n\t"
150  "add %9, %6 \n\t"
151 
152  BRANCHLESS_GET_CABAC("%4", "%q4", "(%6)", "%3", "%w3",
153  "%5", "%q5", "%k0", "%b0",
154  "%c12(%7)", "%c13(%7)",
158  "%15")
159 
160  "mov %1, %6 \n\t"
161  "test $1, %4 \n\t"
162  " jz 4f \n\t"
163 
164 #ifdef BROKEN_RELOCATIONS
165  "movzb %c14(%15, %q6), %6\n\t"
166 #else
167  "movzb "MANGLE(ff_h264_cabac_tables)"+%c14(%6), %6\n\t"
168 #endif
169  "add %11, %6 \n\t"
170 
171  BRANCHLESS_GET_CABAC("%4", "%q4", "(%6)", "%3", "%w3",
172  "%5", "%q5", "%k0", "%b0",
173  "%c12(%7)", "%c13(%7)",
177  "%15")
178 
179  "mov %2, %0 \n\t"
180  "mov %1, %6 \n\t"
181  "mov %k6, (%0) \n\t"
182 
183  "test $1, %4 \n\t"
184  " jnz 5f \n\t"
185 
186  "add"OPSIZE" $4, %2 \n\t"
187 
188  "4: \n\t"
189  "add $1, %6 \n\t"
190  "mov %6, %1 \n\t"
191  "cmp $63, %6 \n\t"
192  " jb 3b \n\t"
193  "mov %2, %0 \n\t"
194  "mov %k6, (%0) \n\t"
195  "5: \n\t"
196  "addl %8, %k0 \n\t"
197  "shr $2, %k0 \n\t"
198  : "=&q"(coeff_count), "+"REG64(last), "+"REG64(index), "+&r"(c->low),
199  "=&r"(bit), "+&r"(c->range), "=&r"(state)
200  : "r"(c), "m"(minusindex), "m"(significant_coeff_ctx_base),
201  REG64(sig_off), REG64(last_coeff_ctx_base),
202  "i"(offsetof(CABACContext, bytestream)),
203  "i"(offsetof(CABACContext, bytestream_end)),
205  : "%"REG_c, "memory"
206  );
207  return coeff_count;
208 }
209 #endif /* HAVE_7REGS && BROKEN_COMPILER */
210 
211 #endif /* HAVE_INLINE_ASM */
212 #endif /* AVCODEC_X86_H264_I386_H */