| 1 | /* |
1 | /* |
| 2 | * libecb |
2 | * libecb - http://software.schmorp.de/pkg/libecb |
| 3 | * |
3 | * |
| 4 | * Copyright (©) 2009-2011 Marc Alexander Lehmann |
4 | * Copyright (©) 2009-2011 Marc Alexander Lehmann <libecb@schmorp.de> |
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5 | * Copyright (©) 2011 Emanuele Giaquinta |
| 5 | * All rights reserved. |
6 | * All rights reserved. |
| 6 | * |
7 | * |
| 7 | * Redistribution and use in source and binary forms, with or without modifica- |
8 | * Redistribution and use in source and binary forms, with or without modifica- |
| 8 | * tion, are permitted provided that the following conditions are met: |
9 | * tion, are permitted provided that the following conditions are met: |
| 9 | * |
10 | * |
| … | |
… | |
| 27 | */ |
28 | */ |
| 28 | |
29 | |
| 29 | #ifndef ECB_H |
30 | #ifndef ECB_H |
| 30 | #define ECB_H |
31 | #define ECB_H |
| 31 | |
32 | |
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33 | #ifdef _WIN32 |
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34 | typedef signed char int8_t; |
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35 | typedef unsigned char uint8_t; |
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36 | typedef signed short int16_t; |
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37 | typedef unsigned short uint16_t; |
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38 | typedef signed int int32_t; |
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39 | typedef unsigned int uint32_t; |
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40 | #if __GNUC__ |
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41 | typedef signed long long int64_t; |
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42 | typedef unsigned long long uint64_t; |
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43 | #else /* _MSC_VER || __BORLANDC__ */ |
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44 | typedef signed __int64 int64_t; |
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45 | typedef unsigned __int64 uint64_t; |
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46 | #endif |
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47 | #else |
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48 | #include <inttypes.h> |
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49 | #endif |
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50 | |
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51 | /* many compilers define _GNUC_ to some versions but then only implement |
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52 | * what their idiot authors think are the "more important" extensions, |
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53 | * causing enourmous grief in return for some better fake benchmark numbers. |
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54 | * or so. |
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55 | * we try to detect these and simply assume they are not gcc - if they have |
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56 | * an issue with that they should have done it right in the first place. |
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57 | */ |
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58 | #ifndef ECB_GCC_VERSION |
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59 | #if !defined(__GNUC_MINOR__) || defined(__INTEL_COMPILER) || defined(__SUNPRO_C) || defined(__SUNPRO_CC) || defined(__llvm__) || defined(__clang__) |
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60 | #define ECB_GCC_VERSION(major,minor) 0 |
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61 | #else |
| 32 | #define ECB_GCC_VERSION(major,minor) (__GNUC__ > (major) || (__GNUC__ == (major) && __GNUC_MINOR__ >= (minor))) |
62 | #define ECB_GCC_VERSION(major,minor) (__GNUC__ > (major) || (__GNUC__ == (major) && __GNUC_MINOR__ >= (minor))) |
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63 | #endif |
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64 | #endif |
| 33 | |
65 | |
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66 | /*****************************************************************************/ |
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67 | |
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68 | /* ECB_NO_THREADS - ecb is not used by multiple threads, ever */ |
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69 | /* ECB_NO_SMP - ecb might be used in multiple threads, but only on a single cpu */ |
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70 | |
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71 | #if ECB_NO_THREADS || ECB_NO_SMP |
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72 | #define ECB_MEMORY_FENCE do { } while (0) |
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73 | #define ECB_MEMORY_FENCE_ACQUIRE do { } while (0) |
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74 | #define ECB_MEMORY_FENCE_RELEASE do { } while (0) |
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75 | #endif |
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76 | |
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77 | #ifndef ECB_MEMORY_FENCE |
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78 | #if ECB_GCC_VERSION(2,5) |
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79 | #if __x86 |
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80 | #define ECB_MEMORY_FENCE __asm__ __volatile__ ("lock; orb $0, -1(%%esp)" : : : "memory") |
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81 | #define ECB_MEMORY_FENCE_ACQUIRE ECB_MEMORY_FENCE /* non-lock xchg might be enough */ |
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82 | #define ECB_MEMORY_FENCE_RELEASE do { } while (0) /* unlikely to change in future cpus */ |
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83 | #elif __amd64 |
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84 | #define ECB_MEMORY_FENCE __asm__ __volatile__ ("mfence" : : : "memory") |
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85 | #define ECB_MEMORY_FENCE_ACQUIRE __asm__ __volatile__ ("lfence" : : : "memory") |
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86 | #define ECB_MEMORY_FENCE_RELEASE __asm__ __volatile__ ("sfence") /* play safe - not needed in any current cpu */ |
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87 | #endif |
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88 | #endif |
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89 | #endif |
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90 | |
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91 | #ifndef ECB_MEMORY_FENCE |
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92 | #if ECB_GCC_VERSION(4,4) |
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93 | #define ECB_MEMORY_FENCE __sync_synchronize () |
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94 | #define ECB_MEMORY_FENCE_ACQUIRE ({ char dummy = 0; __sync_lock_test_and_set (&dummy, 1); }) |
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95 | #define ECB_MEMORY_FENCE_RELEASE ({ char dummy = 1; __sync_lock_release (&dummy ); }) |
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96 | #elif _MSC_VER >= 1400 /* VC++ 2005 */ |
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97 | #pragma intrinsic(_ReadBarrier,_WriteBarrier,_ReadWriteBarrier) |
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98 | #define ECB_MEMORY_FENCE _ReadWriteBarrier () |
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99 | #define ECB_MEMORY_FENCE_ACQUIRE _ReadWriteBarrier () /* according to msdn, _ReadBarrier is not a load fence */ |
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100 | #define ECB_MEMORY_FENCE_RELEASE _WriteBarrier () |
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101 | #elif defined(_WIN32) |
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102 | #include <WinNT.h> |
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103 | #define ECB_MEMORY_FENCE MemoryBarrier () /* actually just xchg on x86... scary */ |
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104 | #define ECB_MEMORY_FENCE_ACQUIRE ECB_MEMORY_FENCE |
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105 | #define ECB_MEMORY_FENCE_RELEASE ECB_MEMORY_FENCE |
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106 | #endif |
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107 | #endif |
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108 | |
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109 | #ifndef ECB_MEMORY_FENCE |
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110 | /* |
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111 | * if you get undefined symbol references to pthread_mutex_lock, |
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112 | * or failure to find pthread.h, then you should implement |
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113 | * the ECB_MEMORY_FENCE operations for your cpu/compiler |
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114 | * OR proide pthread.h and link against the posix thread library |
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115 | * of your system. |
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116 | */ |
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117 | #include <pthread.h> |
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118 | |
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119 | static pthread_mutex_t ecb_mf_lock = PTHREAD_MUTEX_INITIALIZER; |
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120 | #define ECB_MEMORY_FENCE do { pthread_mutex_lock (&ecb_mf_lock); pthread_mutex_unlock (&ecb_mf_lock); } while (0) |
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121 | #define ECB_MEMORY_FENCE_ACQUIRE ECB_MEMORY_FENCE |
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122 | #define ECB_MEMORY_FENCE_RELEASE ECB_MEMORY_FENCE |
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123 | #endif |
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124 | |
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125 | /*****************************************************************************/ |
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126 | |
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127 | #define ECB_C99 (__STDC_VERSION__ >= 199901L) |
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128 | |
| 34 | #ifndef __cplusplus |
129 | #if __cplusplus |
| 35 | # if __STDC_VERSION__ >= 199901L |
130 | #define ecb_inline static inline |
| 36 | # define ECB_INLINE inline |
131 | #elif ECB_GCC_VERSION(2,5) |
| 37 | typedef _Bool ecb_bool; |
132 | #define ecb_inline static __inline__ |
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133 | #elif ECB_C99 |
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134 | #define ecb_inline static inline |
| 38 | # else |
135 | #else |
| 39 | # define ECB_INLINE inline /* yeah! */ |
136 | #define ecb_inline static |
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137 | #endif |
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138 | |
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139 | #if ECB_GCC_VERSION(3,3) |
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140 | #define ecb_restrict __restrict__ |
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141 | #elif ECB_C99 |
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142 | #define ecb_restrict restrict |
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143 | #else |
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144 | #define ecb_restrict |
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145 | #endif |
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146 | |
| 40 | typedef int ecb_bool; |
147 | typedef int ecb_bool; |
| 41 | # endif |
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| 42 | #endif |
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| 43 | |
148 | |
| 44 | #define ECB_HEADER_INLINE static ECB_INLINE |
149 | #define ECB_CONCAT_(a, b) a ## b |
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150 | #define ECB_CONCAT(a, b) ECB_CONCAT_(a, b) |
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151 | #define ECB_STRINGIFY_(a) # a |
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152 | #define ECB_STRINGIFY(a) ECB_STRINGIFY_(a) |
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153 | |
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154 | #define ecb_function_ ecb_inline |
| 45 | |
155 | |
| 46 | #if ECB_GCC_VERSION(3,1) |
156 | #if ECB_GCC_VERSION(3,1) |
| 47 | # define ecb_attribute(attrlist) __attribute__(attrlist) |
157 | #define ecb_attribute(attrlist) __attribute__(attrlist) |
| 48 | # define ecb_is_constant(c) __builtin_constant_p (c) |
158 | #define ecb_is_constant(expr) __builtin_constant_p (expr) |
| 49 | # define ecb_expect(expr,value) __builtin_expect ((expr),(value)) |
159 | #define ecb_expect(expr,value) __builtin_expect ((expr),(value)) |
| 50 | # define ecb_prefetch(addr,rw,locality) __builtin_prefetch (addr, rw, locality) |
160 | #define ecb_prefetch(addr,rw,locality) __builtin_prefetch (addr, rw, locality) |
| 51 | #else |
161 | #else |
| 52 | # define ecb_attribute(attrlist) |
162 | #define ecb_attribute(attrlist) |
| 53 | # define ecb_is_constant(c) 0 |
163 | #define ecb_is_constant(expr) 0 |
| 54 | # define ecb_expect(expr,value) (expr) |
164 | #define ecb_expect(expr,value) (expr) |
| 55 | # define ecb_prefetch(addr,rw,locality) |
165 | #define ecb_prefetch(addr,rw,locality) |
| 56 | #endif |
166 | #endif |
| 57 | |
167 | |
| 58 | /* no emulation for ecb_decltype */ |
168 | /* no emulation for ecb_decltype */ |
| 59 | #if ECB_GCC_VERSION(4,5) |
169 | #if ECB_GCC_VERSION(4,5) |
| 60 | # define ecb_decltype(x) __decltype(x) |
170 | #define ecb_decltype(x) __decltype(x) |
| 61 | #elif ECB_GCC_VERSION(3,0) |
171 | #elif ECB_GCC_VERSION(3,0) |
| 62 | # define ecb_decltype(x) typeof(x) |
172 | #define ecb_decltype(x) __typeof(x) |
| 63 | #endif |
173 | #endif |
| 64 | |
174 | |
| 65 | #define ecb_noinline ecb_attribute ((noinline)) |
175 | #define ecb_noinline ecb_attribute ((__noinline__)) |
| 66 | #define ecb_noreturn ecb_attribute ((noreturn)) |
176 | #define ecb_noreturn ecb_attribute ((__noreturn__)) |
| 67 | #define ecb_unused ecb_attribute ((unused)) |
177 | #define ecb_unused ecb_attribute ((__unused__)) |
| 68 | #define ecb_const ecb_attribute ((const)) |
178 | #define ecb_const ecb_attribute ((__const__)) |
| 69 | #define ecb_pure ecb_attribute ((pure)) |
179 | #define ecb_pure ecb_attribute ((__pure__)) |
| 70 | #define ecb_hot ecb_attribute ((hot)) /* 4.3 */ |
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| 71 | #define ecb_cold ecb_attribute ((cold)) /* 4.3 */ |
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| 72 | |
180 | |
| 73 | #if ECB_GCC_VERSION(4,5) |
181 | #if ECB_GCC_VERSION(4,3) |
| 74 | # define ecb_unreachable() __builtin_unreachable () |
182 | #define ecb_artificial ecb_attribute ((__artificial__)) |
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183 | #define ecb_hot ecb_attribute ((__hot__)) |
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184 | #define ecb_cold ecb_attribute ((__cold__)) |
| 75 | #else |
185 | #else |
| 76 | /* this seems to work fine, but gcc always emits a warning for it :/ */ |
186 | #define ecb_artificial |
| 77 | ECB_HEADER_INLINE void ecb_unreachable () ecb_attribute ((noreturn)); |
187 | #define ecb_hot |
| 78 | ECB_HEADER_INLINE void ecb_unreachable () { } |
188 | #define ecb_cold |
| 79 | #endif |
189 | #endif |
| 80 | |
190 | |
| 81 | /* put into ifs if you are very sure that the expression */ |
191 | /* put around conditional expressions if you are very sure that the */ |
| 82 | /* is mostly true or mosty false. note that these return */ |
192 | /* expression is mostly true or mostly false. note that these return */ |
| 83 | /* booleans, not the expression. */ |
193 | /* booleans, not the expression. */ |
| 84 | #define ecb_expect_false(expr) ecb_expect ((expr) ? 1 : 0, 0) |
194 | #define ecb_expect_false(expr) ecb_expect (!!(expr), 0) |
| 85 | #define ecb_expect_true(expr) ecb_expect ((expr) ? 1 : 0, 1) |
195 | #define ecb_expect_true(expr) ecb_expect (!!(expr), 1) |
| 86 | |
196 | /* for compatibility to the rest of the world */ |
| 87 | /* try to tell the compiler that some condition is definitely true */ |
197 | #define ecb_likely(expr) ecb_expect_true (expr) |
| 88 | #define ecb_assume(cond) do { if (!(cond)) unreachable (); } while (0) |
198 | #define ecb_unlikely(expr) ecb_expect_false (expr) |
| 89 | |
199 | |
| 90 | /* count trailing zero bits and count # of one bits */ |
200 | /* count trailing zero bits and count # of one bits */ |
| 91 | #if ECB_GCC_VERSION(3,4) |
201 | #if ECB_GCC_VERSION(3,4) |
| 92 | ECB_HEADER_INLINE int ecb_ctz32 (unsigned int x) { return __builtin_ctz (x); } |
202 | /* we assume int == 32 bit, long == 32 or 64 bit and long long == 64 bit */ |
| 93 | ECB_HEADER_INLINE int ecb_popcount32 (unsigned int x) { return __builtin_popcount (x); } |
203 | #define ecb_ld32(x) (__builtin_clz (x) ^ 31) |
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204 | #define ecb_ld64(x) (__builtin_clzll (x) ^ 63) |
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205 | #define ecb_ctz32(x) __builtin_ctz (x) |
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206 | #define ecb_ctz64(x) __builtin_ctzll (x) |
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207 | #define ecb_popcount32(x) __builtin_popcount (x) |
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208 | /* no popcountll */ |
| 94 | #else |
209 | #else |
| 95 | ECB_HEADER_INLINE |
210 | ecb_function_ int ecb_ctz32 (uint32_t x) ecb_const; |
| 96 | ecb_ctz32 (unsigned int x) ecb_const |
211 | ecb_function_ int |
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212 | ecb_ctz32 (uint32_t x) |
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213 | { |
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214 | int r = 0; |
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215 | |
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216 | x &= ~x + 1; /* this isolates the lowest bit */ |
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217 | |
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218 | #if ECB_branchless_on_i386 |
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219 | r += !!(x & 0xaaaaaaaa) << 0; |
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220 | r += !!(x & 0xcccccccc) << 1; |
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221 | r += !!(x & 0xf0f0f0f0) << 2; |
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222 | r += !!(x & 0xff00ff00) << 3; |
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223 | r += !!(x & 0xffff0000) << 4; |
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224 | #else |
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225 | if (x & 0xaaaaaaaa) r += 1; |
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226 | if (x & 0xcccccccc) r += 2; |
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227 | if (x & 0xf0f0f0f0) r += 4; |
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228 | if (x & 0xff00ff00) r += 8; |
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229 | if (x & 0xffff0000) r += 16; |
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230 | #endif |
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231 | |
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232 | return r; |
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233 | } |
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234 | |
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235 | ecb_function_ int ecb_ctz64 (uint64_t x) ecb_const; |
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236 | ecb_function_ int |
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237 | ecb_ctz64 (uint64_t x) |
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238 | { |
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239 | int shift = x & 0xffffffffU ? 0 : 32; |
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240 | return ecb_ctz32 (x >> shift) + shift; |
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241 | } |
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242 | |
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243 | ecb_function_ int ecb_popcount32 (uint32_t x) ecb_const; |
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244 | ecb_function_ int |
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245 | ecb_popcount32 (uint32_t x) |
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246 | { |
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247 | x -= (x >> 1) & 0x55555555; |
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248 | x = ((x >> 2) & 0x33333333) + (x & 0x33333333); |
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249 | x = ((x >> 4) + x) & 0x0f0f0f0f; |
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250 | x *= 0x01010101; |
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251 | |
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252 | return x >> 24; |
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253 | } |
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254 | |
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255 | ecb_function_ int ecb_ld32 (uint32_t x) ecb_const; |
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256 | ecb_function_ int ecb_ld32 (uint32_t x) |
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257 | { |
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258 | int r = 0; |
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259 | |
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260 | if (x >> 16) { x >>= 16; r += 16; } |
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261 | if (x >> 8) { x >>= 8; r += 8; } |
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262 | if (x >> 4) { x >>= 4; r += 4; } |
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263 | if (x >> 2) { x >>= 2; r += 2; } |
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264 | if (x >> 1) { r += 1; } |
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265 | |
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266 | return r; |
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267 | } |
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268 | |
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269 | ecb_function_ int ecb_ld64 (uint64_t x) ecb_const; |
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270 | ecb_function_ int ecb_ld64 (uint64_t x) |
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271 | { |
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272 | int r = 0; |
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273 | |
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274 | if (x >> 32) { x >>= 32; r += 32; } |
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275 | |
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276 | return r + ecb_ld32 (x); |
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277 | } |
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278 | #endif |
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279 | |
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280 | /* popcount64 is only available on 64 bit cpus as gcc builtin */ |
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281 | /* so for this version we are lazy */ |
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282 | ecb_function_ int ecb_popcount64 (uint64_t x) ecb_const; |
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283 | ecb_function_ int |
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284 | ecb_popcount64 (uint64_t x) |
| 97 | { |
285 | { |
| 98 | int r = 0; |
286 | return ecb_popcount32 (x) + ecb_popcount32 (x >> 32); |
| 99 | |
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| 100 | x &= -x; /* this isolates the lowest bit */ |
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| 101 | |
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| 102 | if (x & 0xaaaaaaaa) r += 1; |
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| 103 | if (x & 0xcccccccc) r += 2; |
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| 104 | if (x & 0xf0f0f0f0) r += 4; |
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| 105 | if (x & 0xff00ff00) r += 8; |
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| 106 | if (x & 0xffff0000) r += 16; |
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| 107 | |
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| 108 | return r; |
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| 109 | } |
287 | } |
| 110 | |
288 | |
| 111 | ECB_HEADER_INLINE |
289 | ecb_inline uint8_t ecb_rotl8 (uint8_t x, unsigned int count) ecb_const; |
| 112 | ecb_popcount32 (unsigned int x) ecb_const |
290 | ecb_inline uint8_t ecb_rotr8 (uint8_t x, unsigned int count) ecb_const; |
| 113 | { |
291 | ecb_inline uint16_t ecb_rotl16 (uint16_t x, unsigned int count) ecb_const; |
| 114 | x -= (x >> 1) & 0x55555555; |
292 | ecb_inline uint16_t ecb_rotr16 (uint16_t x, unsigned int count) ecb_const; |
| 115 | x = ((x >> 2) & 0x33333333) + (x & 0x33333333); |
293 | ecb_inline uint32_t ecb_rotl32 (uint32_t x, unsigned int count) ecb_const; |
| 116 | x = ((x >> 4) + x) & 0x0f0f0f0f; |
294 | ecb_inline uint32_t ecb_rotr32 (uint32_t x, unsigned int count) ecb_const; |
| 117 | x *= 0x01010101; |
295 | ecb_inline uint64_t ecb_rotl64 (uint64_t x, unsigned int count) ecb_const; |
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296 | ecb_inline uint64_t ecb_rotr64 (uint64_t x, unsigned int count) ecb_const; |
| 118 | |
297 | |
| 119 | return x >> 24; |
298 | ecb_inline uint8_t ecb_rotl8 (uint8_t x, unsigned int count) { return (x >> ( 8 - count)) | (x << count); } |
| 120 | } |
299 | ecb_inline uint8_t ecb_rotr8 (uint8_t x, unsigned int count) { return (x << ( 8 - count)) | (x >> count); } |
| 121 | #endif |
300 | ecb_inline uint16_t ecb_rotl16 (uint16_t x, unsigned int count) { return (x >> (16 - count)) | (x << count); } |
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301 | ecb_inline uint16_t ecb_rotr16 (uint16_t x, unsigned int count) { return (x << (16 - count)) | (x >> count); } |
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302 | ecb_inline uint32_t ecb_rotl32 (uint32_t x, unsigned int count) { return (x >> (32 - count)) | (x << count); } |
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303 | ecb_inline uint32_t ecb_rotr32 (uint32_t x, unsigned int count) { return (x << (32 - count)) | (x >> count); } |
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304 | ecb_inline uint64_t ecb_rotl64 (uint64_t x, unsigned int count) { return (x >> (64 - count)) | (x << count); } |
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305 | ecb_inline uint64_t ecb_rotr64 (uint64_t x, unsigned int count) { return (x << (64 - count)) | (x >> count); } |
| 122 | |
306 | |
| 123 | ECB_HEADER_INLINE unsigned char |
307 | #if ECB_GCC_VERSION(4,3) |
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308 | #define ecb_bswap16(x) (__builtin_bswap32 (x) >> 16) |
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309 | #define ecb_bswap32(x) __builtin_bswap32 (x) |
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310 | #define ecb_bswap64(x) __builtin_bswap64 (x) |
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311 | #else |
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312 | ecb_function_ uint16_t ecb_bswap16 (uint16_t x) ecb_const; |
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313 | ecb_function_ uint16_t |
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314 | ecb_bswap16 (uint16_t x) |
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315 | { |
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316 | return ecb_rotl16 (x, 8); |
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317 | } |
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318 | |
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319 | ecb_function_ uint32_t ecb_bswap32 (uint32_t x) ecb_const; |
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320 | ecb_function_ uint32_t |
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321 | ecb_bswap32 (uint32_t x) |
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322 | { |
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323 | return (((uint32_t)ecb_bswap16 (x)) << 16) | ecb_bswap16 (x >> 16); |
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324 | } |
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325 | |
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326 | ecb_function_ uint64_t ecb_bswap64 (uint64_t x) ecb_const; |
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327 | ecb_function_ uint64_t |
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328 | ecb_bswap64 (uint64_t x) |
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329 | { |
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330 | return (((uint64_t)ecb_bswap32 (x)) << 32) | ecb_bswap32 (x >> 32); |
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331 | } |
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332 | #endif |
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333 | |
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334 | #if ECB_GCC_VERSION(4,5) |
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335 | #define ecb_unreachable() __builtin_unreachable () |
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336 | #else |
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337 | /* this seems to work fine, but gcc always emits a warning for it :/ */ |
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338 | ecb_function_ void ecb_unreachable (void) ecb_noreturn; |
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339 | ecb_function_ void ecb_unreachable (void) { } |
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340 | #endif |
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341 | |
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342 | /* try to tell the compiler that some condition is definitely true */ |
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343 | #define ecb_assume(cond) do { if (!(cond)) ecb_unreachable (); } while (0) |
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344 | |
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345 | ecb_function_ unsigned char ecb_byteorder_helper (void) ecb_const; |
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346 | ecb_function_ unsigned char |
| 124 | ecb_byteorder_helper () ecb_const |
347 | ecb_byteorder_helper (void) |
| 125 | { |
348 | { |
| 126 | const uint32_t u = 0x11223344; |
349 | const uint32_t u = 0x11223344; |
| 127 | return *(unsigned char *)&u; |
350 | return *(unsigned char *)&u; |
| 128 | } |
351 | } |
| 129 | |
352 | |
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353 | ecb_function_ ecb_bool ecb_big_endian (void) ecb_const; |
| 130 | ECB_HEADER_INLINE ecb_bool ecb_big_endian () ecb_const { return ecb_byteorder_helper () == 0x11; }; |
354 | ecb_function_ ecb_bool ecb_big_endian (void) { return ecb_byteorder_helper () == 0x11; } |
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355 | ecb_function_ ecb_bool ecb_little_endian (void) ecb_const; |
| 131 | ECB_HEADER_INLINE ecb_bool ecb_little_endian () ecb_const { return ecb_byteorder_helper () == 0x44; }; |
356 | ecb_function_ ecb_bool ecb_little_endian (void) { return ecb_byteorder_helper () == 0x44; } |
| 132 | |
357 | |
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358 | #if ECB_GCC_VERSION(3,0) || ECB_C99 |
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359 | #define ecb_mod(m,n) ((m) % (n) + ((m) % (n) < 0 ? (n) : 0)) |
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360 | #else |
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361 | #define ecb_mod(m,n) ((m) < 0 ? ((n) - 1 - ((-1 - (m)) % (n))) : ((m) % (n))) |
| 133 | #endif |
362 | #endif |
| 134 | |
363 | |
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364 | #if ecb_cplusplus_does_not_suck |
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365 | /* does not work for local types (http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2008/n2657.htm) */ |
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366 | template<typename T, int N> |
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367 | static inline int ecb_array_length (const T (&arr)[N]) |
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368 | { |
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369 | return N; |
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370 | } |
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371 | #else |
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372 | #define ecb_array_length(name) (sizeof (name) / sizeof (name [0])) |
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373 | #endif |
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374 | |
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375 | #endif |
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376 | |
