|
0
|
1 /*
|
|
|
2 * Copyright (c) 2010 Mans Rullgard <mans@mansr.com>
|
|
|
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 AVUTIL_INTMATH_H
|
|
|
22 #define AVUTIL_INTMATH_H
|
|
|
23
|
|
|
24 #include <stdint.h>
|
|
|
25
|
|
|
26 #include "config.h"
|
|
|
27 #include "attributes.h"
|
|
|
28
|
|
|
29 #if ARCH_ARM
|
|
|
30 # include "arm/intmath.h"
|
|
|
31 #endif
|
|
|
32
|
|
|
33 /**
|
|
|
34 * @addtogroup lavu_internal
|
|
|
35 * @{
|
|
|
36 */
|
|
|
37
|
|
|
38 #if HAVE_FAST_CLZ
|
|
|
39 #if AV_GCC_VERSION_AT_LEAST(3,4)
|
|
|
40 #ifndef ff_log2
|
|
|
41 # define ff_log2(x) (31 - __builtin_clz((x)|1))
|
|
|
42 # ifndef ff_log2_16bit
|
|
|
43 # define ff_log2_16bit av_log2
|
|
|
44 # endif
|
|
|
45 #endif /* ff_log2 */
|
|
|
46 #elif defined( __INTEL_COMPILER )
|
|
|
47 #ifndef ff_log2
|
|
|
48 # define ff_log2(x) (_bit_scan_reverse(x|1))
|
|
|
49 # ifndef ff_log2_16bit
|
|
|
50 # define ff_log2_16bit av_log2
|
|
|
51 # endif
|
|
|
52 #endif /* ff_log2 */
|
|
|
53 #endif
|
|
|
54 #endif /* AV_GCC_VERSION_AT_LEAST(3,4) */
|
|
|
55
|
|
|
56 extern const uint8_t ff_log2_tab[256];
|
|
|
57
|
|
|
58 #ifndef ff_log2
|
|
|
59 #define ff_log2 ff_log2_c
|
|
|
60 #if !defined( _MSC_VER )
|
|
|
61 static av_always_inline av_const int ff_log2_c(unsigned int v)
|
|
|
62 {
|
|
|
63 int n = 0;
|
|
|
64 if (v & 0xffff0000) {
|
|
|
65 v >>= 16;
|
|
|
66 n += 16;
|
|
|
67 }
|
|
|
68 if (v & 0xff00) {
|
|
|
69 v >>= 8;
|
|
|
70 n += 8;
|
|
|
71 }
|
|
|
72 n += ff_log2_tab[v];
|
|
|
73
|
|
|
74 return n;
|
|
|
75 }
|
|
|
76 #else
|
|
|
77 static av_always_inline av_const int ff_log2_c(unsigned int v)
|
|
|
78 {
|
|
|
79 unsigned long n;
|
|
|
80 _BitScanReverse(&n, v|1);
|
|
|
81 return n;
|
|
|
82 }
|
|
|
83 #define ff_log2_16bit av_log2
|
|
|
84 #endif
|
|
|
85 #endif
|
|
|
86
|
|
|
87 #ifndef ff_log2_16bit
|
|
|
88 #define ff_log2_16bit ff_log2_16bit_c
|
|
|
89 static av_always_inline av_const int ff_log2_16bit_c(unsigned int v)
|
|
|
90 {
|
|
|
91 int n = 0;
|
|
|
92 if (v & 0xff00) {
|
|
|
93 v >>= 8;
|
|
|
94 n += 8;
|
|
|
95 }
|
|
|
96 n += ff_log2_tab[v];
|
|
|
97
|
|
|
98 return n;
|
|
|
99 }
|
|
|
100 #endif
|
|
|
101
|
|
|
102 #define av_log2 ff_log2
|
|
|
103 #define av_log2_16bit ff_log2_16bit
|
|
|
104
|
|
|
105 /**
|
|
|
106 * @}
|
|
|
107 */
|
|
|
108
|
|
|
109 /**
|
|
|
110 * @addtogroup lavu_math
|
|
|
111 * @{
|
|
|
112 */
|
|
|
113
|
|
|
114 #if HAVE_FAST_CLZ
|
|
|
115 #if AV_GCC_VERSION_AT_LEAST(3,4)
|
|
|
116 #ifndef ff_ctz
|
|
|
117 #define ff_ctz(v) __builtin_ctz(v)
|
|
|
118 #endif
|
|
|
119 #elif defined( __INTEL_COMPILER )
|
|
|
120 #ifndef ff_ctz
|
|
|
121 #define ff_ctz(v) _bit_scan_forward(v)
|
|
|
122 #endif
|
|
|
123 #endif
|
|
|
124 #endif
|
|
|
125
|
|
|
126 #ifndef ff_ctz
|
|
|
127 #define ff_ctz ff_ctz_c
|
|
|
128 #if !defined( _MSC_VER )
|
|
|
129 static av_always_inline av_const int ff_ctz_c(int v)
|
|
|
130 {
|
|
|
131 int c;
|
|
|
132
|
|
|
133 if (v & 0x1)
|
|
|
134 return 0;
|
|
|
135
|
|
|
136 c = 1;
|
|
|
137 if (!(v & 0xffff)) {
|
|
|
138 v >>= 16;
|
|
|
139 c += 16;
|
|
|
140 }
|
|
|
141 if (!(v & 0xff)) {
|
|
|
142 v >>= 8;
|
|
|
143 c += 8;
|
|
|
144 }
|
|
|
145 if (!(v & 0xf)) {
|
|
|
146 v >>= 4;
|
|
|
147 c += 4;
|
|
|
148 }
|
|
|
149 if (!(v & 0x3)) {
|
|
|
150 v >>= 2;
|
|
|
151 c += 2;
|
|
|
152 }
|
|
|
153 c -= v & 0x1;
|
|
|
154
|
|
|
155 return c;
|
|
|
156 }
|
|
|
157 #else
|
|
|
158 static av_always_inline av_const int ff_ctz_c( int v )
|
|
|
159 {
|
|
|
160 unsigned long c;
|
|
|
161 _BitScanForward(&c, v);
|
|
|
162 return c;
|
|
|
163 }
|
|
|
164 #endif
|
|
|
165 #endif
|
|
|
166
|
|
|
167 /**
|
|
|
168 * Trailing zero bit count.
|
|
|
169 *
|
|
|
170 * @param v input value. If v is 0, the result is undefined.
|
|
|
171 * @return the number of trailing 0-bits
|
|
|
172 */
|
|
|
173 int av_ctz(int v);
|
|
|
174
|
|
|
175 /**
|
|
|
176 * @}
|
|
|
177 */
|
|
|
178 #endif /* AVUTIL_INTMATH_H */
|
