FFmpeg
mem_internal.h
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1 /*
2  * Copyright (c) 2002 Fabrice Bellard
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_MEM_INTERNAL_H
22 #define AVUTIL_MEM_INTERNAL_H
23 
24 #include "config.h"
25 
26 #include <stdint.h>
27 
28 #include "attributes.h"
29 #include "macros.h"
30 #include "mem.h"
31 #include "version.h"
32 
33 /**
34  * @def DECLARE_ALIGNED(n,t,v)
35  * Declare a variable that is aligned in memory.
36  *
37  * @code{.c}
38  * DECLARE_ALIGNED(16, uint16_t, aligned_int) = 42;
39  * DECLARE_ALIGNED(32, uint8_t, aligned_array)[128];
40  *
41  * // The default-alignment equivalent would be
42  * uint16_t aligned_int = 42;
43  * uint8_t aligned_array[128];
44  * @endcode
45  *
46  * @param n Minimum alignment in bytes
47  * @param t Type of the variable (or array element)
48  * @param v Name of the variable
49  */
50 
51 /**
52  * @def DECLARE_ASM_ALIGNED(n,t,v)
53  * Declare an aligned variable appropriate for use in inline assembly code.
54  *
55  * @code{.c}
56  * DECLARE_ASM_ALIGNED(16, uint64_t, pw_08) = UINT64_C(0x0008000800080008);
57  * @endcode
58  *
59  * @param n Minimum alignment in bytes
60  * @param t Type of the variable (or array element)
61  * @param v Name of the variable
62  */
63 
64 /**
65  * @def DECLARE_ASM_CONST(n,t,v)
66  * Declare a static constant aligned variable appropriate for use in inline
67  * assembly code.
68  *
69  * @code{.c}
70  * DECLARE_ASM_CONST(16, uint64_t, pw_08) = UINT64_C(0x0008000800080008);
71  * @endcode
72  *
73  * @param n Minimum alignment in bytes
74  * @param t Type of the variable (or array element)
75  * @param v Name of the variable
76  */
77 
78 #if defined(__INTEL_COMPILER) && __INTEL_COMPILER < 1110 || defined(__SUNPRO_C)
79  #define DECLARE_ALIGNED(n,t,v) t __attribute__ ((aligned (n))) v
80  #define DECLARE_ASM_ALIGNED(n,t,v) t __attribute__ ((aligned (n))) v
81  #define DECLARE_ASM_CONST(n,t,v) const t __attribute__ ((aligned (n))) v
82 #elif defined(__DJGPP__)
83  #define DECLARE_ALIGNED(n,t,v) t __attribute__ ((aligned (FFMIN(n, 16)))) v
84  #define DECLARE_ASM_ALIGNED(n,t,v) t av_used __attribute__ ((aligned (FFMIN(n, 16)))) v
85  #define DECLARE_ASM_CONST(n,t,v) static const t av_used __attribute__ ((aligned (FFMIN(n, 16)))) v
86 #elif defined(__GNUC__) || defined(__clang__)
87  #define DECLARE_ALIGNED(n,t,v) t __attribute__ ((aligned (n))) v
88  #define DECLARE_ASM_ALIGNED(n,t,v) t av_used __attribute__ ((aligned (n))) v
89  #define DECLARE_ASM_CONST(n,t,v) static const t av_used __attribute__ ((aligned (n))) v
90 #elif defined(_MSC_VER)
91  #define DECLARE_ALIGNED(n,t,v) __declspec(align(n)) t v
92  #define DECLARE_ASM_ALIGNED(n,t,v) __declspec(align(n)) t v
93  #define DECLARE_ASM_CONST(n,t,v) __declspec(align(n)) static const t v
94 #else
95  #define DECLARE_ALIGNED(n,t,v) t v
96  #define DECLARE_ASM_ALIGNED(n,t,v) t v
97  #define DECLARE_ASM_CONST(n,t,v) static const t v
98 #endif
99 
100 // Some broken preprocessors need a second expansion
101 // to be forced to tokenize __VA_ARGS__
102 #define E1(x) x
103 
104 #define LOCAL_ALIGNED_A(a, t, v, s, o, ...) \
105  uint8_t la_##v[sizeof(t s o) + (a)]; \
106  t (*v) o = (void *)FFALIGN((uintptr_t)la_##v, a)
107 
108 #define LOCAL_ALIGNED_D(a, t, v, s, o, ...) \
109  DECLARE_ALIGNED(a, t, la_##v) s o; \
110  t (*v) o = la_##v
111 
112 #define LOCAL_ALIGNED(a, t, v, ...) LOCAL_ALIGNED_##a(t, v, __VA_ARGS__)
113 
114 #if HAVE_LOCAL_ALIGNED
115 # define LOCAL_ALIGNED_4(t, v, ...) E1(LOCAL_ALIGNED_D(4, t, v, __VA_ARGS__,,))
116 #else
117 # define LOCAL_ALIGNED_4(t, v, ...) E1(LOCAL_ALIGNED_A(4, t, v, __VA_ARGS__,,))
118 #endif
119 
120 #if HAVE_LOCAL_ALIGNED
121 # define LOCAL_ALIGNED_8(t, v, ...) E1(LOCAL_ALIGNED_D(8, t, v, __VA_ARGS__,,))
122 #else
123 # define LOCAL_ALIGNED_8(t, v, ...) E1(LOCAL_ALIGNED_A(8, t, v, __VA_ARGS__,,))
124 #endif
125 
126 #if HAVE_LOCAL_ALIGNED
127 # define LOCAL_ALIGNED_16(t, v, ...) E1(LOCAL_ALIGNED_D(16, t, v, __VA_ARGS__,,))
128 #else
129 # define LOCAL_ALIGNED_16(t, v, ...) E1(LOCAL_ALIGNED_A(16, t, v, __VA_ARGS__,,))
130 #endif
131 
132 #if HAVE_LOCAL_ALIGNED
133 # define LOCAL_ALIGNED_32(t, v, ...) E1(LOCAL_ALIGNED_D(32, t, v, __VA_ARGS__,,))
134 #else
135 # define LOCAL_ALIGNED_32(t, v, ...) E1(LOCAL_ALIGNED_A(32, t, v, __VA_ARGS__,,))
136 #endif
137 
138 #endif /* AVUTIL_MEM_INTERNAL_H */
macros.h
attributes.h
version.h
mem.h