FFmpeg
cabac.h
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1 /*
2  * Loongson SIMD optimized h264chroma
3  *
4  * Copyright (c) 2018 Loongson Technology Corporation Limited
5  * Contributed by Shiyou Yin <yinshiyou-hf@loongson.cn>
6  * Gu Xiwei(guxiwei-hf@loongson.cn)
7  *
8  * This file is part of FFmpeg.
9  *
10  * FFmpeg is free software; you can redistribute it and/or
11  * modify it under the terms of the GNU Lesser General Public
12  * License as published by the Free Software Foundation; either
13  * version 2.1 of the License, or (at your option) any later version.
14  *
15  * FFmpeg is distributed in the hope that it will be useful,
16  * but WITHOUT ANY WARRANTY; without even the implied warranty of
17  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
18  * Lesser General Public License for more details.
19  *
20  * You should have received a copy of the GNU Lesser General Public
21  * License along with FFmpeg; if not, write to the Free Software
22  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
23  */
24 
25 #ifndef AVCODEC_MIPS_CABAC_H
26 #define AVCODEC_MIPS_CABAC_H
27 
28 #include "libavutil/attributes.h"
29 #include "libavcodec/cabac.h"
30 #include "libavutil/mips/mmiutils.h"
31 #include "config.h"
32 
33 #if !HAVE_MIPS32R6 && !HAVE_MIPS64R6
34 #define get_cabac_inline get_cabac_inline_mips
35 static av_always_inline int get_cabac_inline_mips(CABACContext *c,
36  uint8_t * const state){
37  mips_reg tmp0, tmp1, tmp2, bit;
38 
39  __asm__ volatile (
40  "lbu %[bit], 0(%[state]) \n\t"
41  "and %[tmp0], %[c_range], 0xC0 \n\t"
42  PTR_SLL "%[tmp0], %[tmp0], 0x01 \n\t"
43  PTR_ADDU "%[tmp0], %[tmp0], %[tables] \n\t"
44  PTR_ADDU "%[tmp0], %[tmp0], %[bit] \n\t"
45  /* tmp1: RangeLPS */
46  "lbu %[tmp1], %[lps_off](%[tmp0]) \n\t"
47 
48  PTR_SUBU "%[c_range], %[c_range], %[tmp1] \n\t"
49  PTR_SLL "%[tmp0], %[c_range], 0x11 \n\t"
50  "slt %[tmp2], %[tmp0], %[c_low] \n\t"
51  "beqz %[tmp2], 1f \n\t"
52  "move %[c_range], %[tmp1] \n\t"
53  "not %[bit], %[bit] \n\t"
54  PTR_SUBU "%[c_low], %[c_low], %[tmp0] \n\t"
55 
56  "1: \n\t"
57  /* tmp1: *state */
58  PTR_ADDU "%[tmp0], %[tables], %[bit] \n\t"
59  "lbu %[tmp1], %[mlps_off](%[tmp0]) \n\t"
60  /* tmp2: lps_mask */
61  PTR_ADDU "%[tmp0], %[tables], %[c_range] \n\t"
62  "lbu %[tmp2], %[norm_off](%[tmp0]) \n\t"
63 
64  "sb %[tmp1], 0(%[state]) \n\t"
65  "and %[bit], %[bit], 0x01 \n\t"
66  PTR_SLL "%[c_range], %[c_range], %[tmp2] \n\t"
67  PTR_SLL "%[c_low], %[c_low], %[tmp2] \n\t"
68 
69  "and %[tmp1], %[c_low], %[cabac_mask] \n\t"
70  "bnez %[tmp1], 1f \n\t"
71  PTR_ADDIU "%[tmp0], %[c_low], -0X01 \n\t"
72  "xor %[tmp0], %[c_low], %[tmp0] \n\t"
73  PTR_SRA "%[tmp0], %[tmp0], 0x0f \n\t"
74  PTR_ADDU "%[tmp0], %[tmp0], %[tables] \n\t"
75  /* tmp2: ff_h264_norm_shift[x >> (CABAC_BITS - 1)] */
76  "lbu %[tmp2], %[norm_off](%[tmp0]) \n\t"
77 #if HAVE_BIGENDIAN
78  "lhu %[tmp0], 0(%[c_bytestream]) \n\t"
79 #else
80  "lhu %[tmp0], 0(%[c_bytestream]) \n\t"
81 #if HAVE_MIPS32R2 || HAVE_MIPS64R2
82  "wsbh %[tmp0], %[tmp0] \n\t"
83 #else
84  "and %[tmp1], %[tmp0], 0xff00ff00 \n\t"
85  "srl %[tmp1], %[tmp1], 8 \n\t"
86  "and %[tmp0], %[tmp0], 0x00ff00ff \n\t"
87  "sll %[tmp0], %[tmp0], 8 \n\t"
88  "or %[tmp0], %[tmp0], %[tmp1] \n\t"
89 #endif
90 #endif
91  PTR_SLL "%[tmp0], %[tmp0], 0x01 \n\t"
92  PTR_SUBU "%[tmp0], %[tmp0], %[cabac_mask] \n\t"
93 
94  "li %[tmp1], 0x07 \n\t"
95  PTR_SUBU "%[tmp1], %[tmp1], %[tmp2] \n\t"
96  PTR_SLL "%[tmp0], %[tmp0], %[tmp1] \n\t"
97  PTR_ADDU "%[c_low], %[c_low], %[tmp0] \n\t"
98 
99 #if UNCHECKED_BITSTREAM_READER
100  PTR_ADDIU "%[c_bytestream], %[c_bytestream], 0x02 \n\t"
101 #else
102  "slt %[tmp0], %[c_bytestream], %[c_bytestream_end] \n\t"
103  PTR_ADDIU "%[tmp2], %[c_bytestream], 0x02 \n\t"
104  "movn %[c_bytestream], %[tmp2], %[tmp0] \n\t"
105 #endif
106  "1: \n\t"
107  : [bit]"=&r"(bit), [tmp0]"=&r"(tmp0), [tmp1]"=&r"(tmp1), [tmp2]"=&r"(tmp2),
108  [c_range]"+&r"(c->range), [c_low]"+&r"(c->low),
109  [c_bytestream]"+&r"(c->bytestream)
110  : [state]"r"(state), [tables]"r"(ff_h264_cabac_tables),
111 #if !UNCHECKED_BITSTREAM_READER
112  [c_bytestream_end]"r"(c->bytestream_end),
113 #endif
114  [lps_off]"i"(H264_LPS_RANGE_OFFSET),
115  [mlps_off]"i"(H264_MLPS_STATE_OFFSET + 128),
116  [norm_off]"i"(H264_NORM_SHIFT_OFFSET),
117  [cabac_mask]"r"(CABAC_MASK)
118  : "memory"
119  );
120 
121  return bit;
122 }
123 
124 #define get_cabac_bypass get_cabac_bypass_mips
125 static av_always_inline int get_cabac_bypass_mips(CABACContext *c)
126 {
127  mips_reg tmp0, tmp1;
128  int res = 0;
129  __asm__ volatile(
130  PTR_SLL "%[c_low], %[c_low], 0x01 \n\t"
131  "and %[tmp0], %[c_low], %[cabac_mask] \n\t"
132  "bnez %[tmp0], 1f \n\t"
133 #if HAVE_BIGENDIAN
134  "lhu %[tmp1], 0(%[c_bytestream]) \n\t"
135 #else
136  "lhu %[tmp1], 0(%[c_bytestream]) \n\t"
137 #if HAVE_MIPS32R2 || HAVE_MIPS64R2
138  "wsbh %[tmp1], %[tmp1] \n\t"
139 #else
140  "and %[tmp0], %[tmp1], 0xff00ff00 \n\t"
141  "srl %[tmp0], %[tmp0], 8 \n\t"
142  "and %[tmp1], %[tmp1], 0x00ff00ff \n\t"
143  "sll %[tmp1], %[tmp1], 8 \n\t"
144  "or %[tmp1], %[tmp1], %[tmp0] \n\t"
145 #endif
146 #endif
147  PTR_SLL "%[tmp1], %[tmp1], 0x01 \n\t"
148  PTR_SUBU "%[tmp1], %[tmp1], %[cabac_mask] \n\t"
149  PTR_ADDU "%[c_low], %[c_low], %[tmp1] \n\t"
150 #if UNCHECKED_BITSTREAM_READER
151  PTR_ADDIU "%[c_bytestream], %[c_bytestream], 0x02 \n\t"
152 #else
153  "slt %[tmp0], %[c_bytestream], %[c_bytestream_end] \n\t"
154  PTR_ADDIU "%[tmp1], %[c_bytestream], 0x02 \n\t"
155  "movn %[c_bytestream], %[tmp1], %[tmp0] \n\t"
156 #endif
157  "1: \n\t"
158  PTR_SLL "%[tmp1], %[c_range], 0x11 \n\t"
159  "slt %[tmp0], %[c_low], %[tmp1] \n\t"
160  PTR_SUBU "%[tmp1], %[c_low], %[tmp1] \n\t"
161  "movz %[res], %[one], %[tmp0] \n\t"
162  "movz %[c_low], %[tmp1], %[tmp0] \n\t"
163  : [tmp0]"=&r"(tmp0), [tmp1]"=&r"(tmp1), [res]"+&r"(res),
164  [c_range]"+&r"(c->range), [c_low]"+&r"(c->low),
165  [c_bytestream]"+&r"(c->bytestream)
166  : [cabac_mask]"r"(CABAC_MASK),
167 #if !UNCHECKED_BITSTREAM_READER
168  [c_bytestream_end]"r"(c->bytestream_end),
169 #endif
170  [one]"r"(0x01)
171  : "memory"
172  );
173  return res;
174 }
175 
176 #define get_cabac_bypass_sign get_cabac_bypass_sign_mips
177 static av_always_inline int get_cabac_bypass_sign_mips(CABACContext *c, int val)
178 {
179  mips_reg tmp0, tmp1;
180  int res = val;
181  __asm__ volatile(
182  PTR_SLL "%[c_low], %[c_low], 0x01 \n\t"
183  "and %[tmp0], %[c_low], %[cabac_mask] \n\t"
184  "bnez %[tmp0], 1f \n\t"
185 #if HAVE_BIGENDIAN
186  "lhu %[tmp1], 0(%[c_bytestream]) \n\t"
187 #else
188  "lhu %[tmp1], 0(%[c_bytestream]) \n\t"
189 #if HAVE_MIPS32R2 || HAVE_MIPS64R2
190  "wsbh %[tmp1], %[tmp1] \n\t"
191 #else
192  "and %[tmp0], %[tmp1], 0xff00ff00 \n\t"
193  "srl %[tmp0], %[tmp0], 8 \n\t"
194  "and %[tmp1], %[tmp1], 0x00ff00ff \n\t"
195  "sll %[tmp1], %[tmp1], 8 \n\t"
196  "or %[tmp1], %[tmp1], %[tmp0] \n\t"
197 #endif
198 #endif
199  PTR_SLL "%[tmp1], %[tmp1], 0x01 \n\t"
200  PTR_SUBU "%[tmp1], %[tmp1], %[cabac_mask] \n\t"
201  PTR_ADDU "%[c_low], %[c_low], %[tmp1] \n\t"
202 #if UNCHECKED_BITSTREAM_READER
203  PTR_ADDIU "%[c_bytestream], %[c_bytestream], 0x02 \n\t"
204 #else
205  "slt %[tmp0], %[c_bytestream], %[c_bytestream_end] \n\t"
206  PTR_ADDIU "%[tmp1], %[c_bytestream], 0x02 \n\t"
207  "movn %[c_bytestream], %[tmp1], %[tmp0] \n\t"
208 #endif
209  "1: \n\t"
210  PTR_SLL "%[tmp1], %[c_range], 0x11 \n\t"
211  "slt %[tmp0], %[c_low], %[tmp1] \n\t"
212  PTR_SUBU "%[tmp1], %[c_low], %[tmp1] \n\t"
213  "movz %[c_low], %[tmp1], %[tmp0] \n\t"
214  PTR_SUBU "%[tmp1], %[zero], %[res] \n\t"
215  "movn %[res], %[tmp1], %[tmp0] \n\t"
216  : [tmp0]"=&r"(tmp0), [tmp1]"=&r"(tmp1), [res]"+&r"(res),
217  [c_range]"+&r"(c->range), [c_low]"+&r"(c->low),
218  [c_bytestream]"+&r"(c->bytestream)
219  : [cabac_mask]"r"(CABAC_MASK),
220 #if !UNCHECKED_BITSTREAM_READER
221  [c_bytestream_end]"r"(c->bytestream_end),
222 #endif
223  [zero]"r"(0x0)
224  : "memory"
225  );
226 
227  return res;
228 }
229 #endif /* !HAVE_MIPS32R6 && !HAVE_MIPS64R6 */
230 #endif /* AVCODEC_MIPS_CABAC_H */
cabac.h
PTR_SLL
#define PTR_SLL
Definition: asmdefs.h:57
get_cabac_bypass_sign_mips
static av_always_inline int get_cabac_bypass_sign_mips(CABACContext *c, int val)
Definition: cabac.h:177
mips_reg
#define mips_reg
Definition: asmdefs.h:46
bit
#define bit(string, value)
Definition: cbs_mpeg2.c:58
tables
Writing a table generator This documentation is preliminary Parts of the API are not good and should be changed Basic concepts A table generator consists of two *_tablegen c and *_tablegen h The h file will provide the variable declarations and initialization code for the tables
Definition: tablegen.txt:10
val
static double val(void *priv, double ch)
Definition: aeval.c:77
ff_h264_cabac_tables
const uint8_t ff_h264_cabac_tables[512+4 *2 *64+4 *64+63]
mmiutils.h
CABAC_MASK
#define CABAC_MASK
Definition: cabac.h:39
get_cabac_bypass_mips
static av_always_inline int get_cabac_bypass_mips(CABACContext *c)
Definition: cabac.h:125
c
Undefined Behavior In the C some operations are like signed integer dereferencing freed accessing outside allocated Undefined Behavior must not occur in a C it is not safe even if the output of undefined operations is unused The unsafety may seem nit picking but Optimizing compilers have in fact optimized code on the assumption that no undefined Behavior occurs Optimizing code based on wrong assumptions can and has in some cases lead to effects beyond the output of computations The signed integer overflow problem in speed critical code Code which is highly optimized and works with signed integers sometimes has the problem that often the output of the computation does not c
Definition: undefined.txt:32
H264_LPS_RANGE_OFFSET
#define H264_LPS_RANGE_OFFSET
Definition: cabac.h:34
PTR_SUBU
#define PTR_SUBU
Definition: asmdefs.h:52
attributes.h
av_always_inline
#define av_always_inline
Definition: attributes.h:49
UNCHECKED_BITSTREAM_READER
#define UNCHECKED_BITSTREAM_READER
Definition: bitstream.h:57
H264_NORM_SHIFT_OFFSET
#define H264_NORM_SHIFT_OFFSET
Definition: cabac.h:33
__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")
PTR_ADDU
#define PTR_ADDU
Definition: asmdefs.h:49
get_cabac_inline_mips
static av_always_inline int get_cabac_inline_mips(CABACContext *c, uint8_t *const state)
Definition: cabac.h:35
PTR_ADDIU
#define PTR_ADDIU
Definition: asmdefs.h:50
zero
#define zero
Definition: regdef.h:64
state
static struct @351 state
H264_MLPS_STATE_OFFSET
#define H264_MLPS_STATE_OFFSET
Definition: cabac.h:35
CABACContext
Definition: cabac.h:41
PTR_SRA
#define PTR_SRA
Definition: asmdefs.h:55
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