Add zero_extend() function
[libav.git] / libavcodec / mathops.h
1 /*
2 * simple math operations
3 * Copyright (c) 2001, 2002 Fabrice Bellard
4 * Copyright (c) 2006 Michael Niedermayer <michaelni@gmx.at> et al
5 *
6 * This file is part of FFmpeg.
7 *
8 * FFmpeg is free software; you can redistribute it and/or
9 * modify it under the terms of the GNU Lesser General Public
10 * License as published by the Free Software Foundation; either
11 * version 2.1 of the License, or (at your option) any later version.
12 *
13 * FFmpeg is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
16 * Lesser General Public License for more details.
17 *
18 * You should have received a copy of the GNU Lesser General Public
19 * License along with FFmpeg; if not, write to the Free Software
20 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
21 */
22 #ifndef AVCODEC_MATHOPS_H
23 #define AVCODEC_MATHOPS_H
24
25 #include "libavutil/common.h"
26
27 #if ARCH_ARM
28 # include "arm/mathops.h"
29 #elif ARCH_AVR32
30 # include "avr32/mathops.h"
31 #elif ARCH_BFIN
32 # include "bfin/mathops.h"
33 #elif ARCH_MIPS
34 # include "mips/mathops.h"
35 #elif ARCH_PPC
36 # include "ppc/mathops.h"
37 #elif ARCH_X86
38 # include "x86/mathops.h"
39 #endif
40
41 /* generic implementation */
42
43 #ifndef MULL
44 # define MULL(a,b,s) (((int64_t)(a) * (int64_t)(b)) >> (s))
45 #endif
46
47 #ifndef MULH
48 //gcc 3.4 creates an incredibly bloated mess out of this
49 //# define MULH(a,b) (((int64_t)(a) * (int64_t)(b))>>32)
50
51 static av_always_inline int MULH(int a, int b){
52 return ((int64_t)(a) * (int64_t)(b))>>32;
53 }
54 #endif
55
56 #ifndef UMULH
57 static av_always_inline unsigned UMULH(unsigned a, unsigned b){
58 return ((uint64_t)(a) * (uint64_t)(b))>>32;
59 }
60 #endif
61
62 #ifndef MUL64
63 # define MUL64(a,b) ((int64_t)(a) * (int64_t)(b))
64 #endif
65
66 #ifndef MAC64
67 # define MAC64(d, a, b) ((d) += MUL64(a, b))
68 #endif
69
70 #ifndef MLS64
71 # define MLS64(d, a, b) ((d) -= MUL64(a, b))
72 #endif
73
74 /* signed 16x16 -> 32 multiply add accumulate */
75 #ifndef MAC16
76 # define MAC16(rt, ra, rb) rt += (ra) * (rb)
77 #endif
78
79 /* signed 16x16 -> 32 multiply */
80 #ifndef MUL16
81 # define MUL16(ra, rb) ((ra) * (rb))
82 #endif
83
84 #ifndef MLS16
85 # define MLS16(rt, ra, rb) ((rt) -= (ra) * (rb))
86 #endif
87
88 /* median of 3 */
89 #ifndef mid_pred
90 #define mid_pred mid_pred
91 static inline av_const int mid_pred(int a, int b, int c)
92 {
93 #if 0
94 int t= (a-b)&((a-b)>>31);
95 a-=t;
96 b+=t;
97 b-= (b-c)&((b-c)>>31);
98 b+= (a-b)&((a-b)>>31);
99
100 return b;
101 #else
102 if(a>b){
103 if(c>b){
104 if(c>a) b=a;
105 else b=c;
106 }
107 }else{
108 if(b>c){
109 if(c>a) b=c;
110 else b=a;
111 }
112 }
113 return b;
114 #endif
115 }
116 #endif
117
118 #ifndef sign_extend
119 static inline av_const int sign_extend(int val, unsigned bits)
120 {
121 return (val << (INT_BIT - bits)) >> (INT_BIT - bits);
122 }
123 #endif
124
125 #ifndef zero_extend
126 static inline av_const unsigned zero_extend(unsigned val, unsigned bits)
127 {
128 return (val << (INT_BIT - bits)) >> (INT_BIT - bits);
129 }
130 #endif
131
132 #ifndef COPY3_IF_LT
133 #define COPY3_IF_LT(x, y, a, b, c, d)\
134 if ((y) < (x)) {\
135 (x) = (y);\
136 (a) = (b);\
137 (c) = (d);\
138 }
139 #endif
140
141 #ifndef NEG_SSR32
142 # define NEG_SSR32(a,s) ((( int32_t)(a))>>(32-(s)))
143 #endif
144
145 #ifndef NEG_USR32
146 # define NEG_USR32(a,s) (((uint32_t)(a))>>(32-(s)))
147 #endif
148
149 #endif /* AVCODEC_MATHOPS_H */
150