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Comparing libecb/ecb.h (file contents):
Revision 1.11 by root, Thu May 26 18:00:42 2011 UTC vs.
Revision 1.17 by root, Thu May 26 18:36:00 2011 UTC

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
5 * Copyright (©) 2011 Emanuele Giaquinta 5 * Copyright (©) 2011 Emanuele Giaquinta
6 * All rights reserved. 6 * All rights reserved.
7 * 7 *
… …
30#ifndef ECB_H 30#ifndef ECB_H
31#define ECB_H 31#define ECB_H
32 32
33#include <inttypes.h> 33#include <inttypes.h>
34 34
35/* many compilers define _GNUC_ to some versions but then only implement
36 * what their idiot authors think are the "more important" extensions,
37 * causing enourmous grief for some better fake benchmark numbers or so.
38 * we try to detect these and simply assume they are not gcc - if they have
39 * an issue with that they should have done it right in the first place.
40 */
41#ifndef ECB_GCC_VERSION
42# if defined(__INTEL_COMPILER) || defined(__SUNPRO_C) || defined(__llvm__)
43# define ECB_GCC_VERSION(major,minor) 0
44# else
35#define ECB_GCC_VERSION(major,minor) (__GNUC__ > (major) || (__GNUC__ == (major) && __GNUC_MINOR__ >= (minor))) 45# define ECB_GCC_VERSION(major,minor) (__GNUC__ > (major) || (__GNUC__ == (major) && __GNUC_MINOR__ >= (minor)))
46# endif
47#endif
36 48
37#ifndef __cplusplus 49#ifndef __cplusplus
38# if __STDC_VERSION__ >= 199901L 50# if __STDC_VERSION__ >= 199901L
39# define ECB_INLINE inline 51# define ECB_INLINE inline
40typedef _Bool ecb_bool; 52typedef _Bool ecb_bool;
… …
76#define ecb_const ecb_attribute ((const)) 88#define ecb_const ecb_attribute ((const))
77#define ecb_pure ecb_attribute ((pure)) 89#define ecb_pure ecb_attribute ((pure))
78#define ecb_hot ecb_attribute ((hot)) /* 4.3 */ 90#define ecb_hot ecb_attribute ((hot)) /* 4.3 */
79#define ecb_cold ecb_attribute ((cold)) /* 4.3 */ 91#define ecb_cold ecb_attribute ((cold)) /* 4.3 */
80 92
81#if ECB_GCC_VERSION(4,5)
82# define ecb_unreachable() __builtin_unreachable ()
83#else
84/* this seems to work fine, but gcc always emits a warning for it :/ */
85ECB_HEADER_INLINE void ecb_unreachable () ecb_attribute ((noreturn));
86ECB_HEADER_INLINE void ecb_unreachable () { }
87#endif
88
89/* put into ifs if you are very sure that the expression */ 93/* put into ifs if you are very sure that the expression */
90/* is mostly true or mosty false. note that these return */ 94/* is mostly true or mosty false. note that these return */
91/* booleans, not the expression. */ 95/* booleans, not the expression. */
92#define ecb_unlikely(expr) ecb_expect (!!(expr), 0) 96#define ecb_unlikely(expr) ecb_expect (!!(expr), 0)
93#define ecb_likely(expr) ecb_expect (!!(expr), 1) 97#define ecb_likely(expr) ecb_expect (!!(expr), 1)
… …
95/* try to tell the compiler that some condition is definitely true */ 99/* try to tell the compiler that some condition is definitely true */
96#define ecb_assume(cond) do { if (!(cond)) unreachable (); } while (0) 100#define ecb_assume(cond) do { if (!(cond)) unreachable (); } while (0)
97 101
98/* count trailing zero bits and count # of one bits */ 102/* count trailing zero bits and count # of one bits */
99#if ECB_GCC_VERSION(3,4) 103#if ECB_GCC_VERSION(3,4)
100ECB_HEADER_INLINE int ecb_ctz32 (uint32_t x) { return __builtin_ctz (x); } 104#define ecb_ctz32 (x) __builtin_ctz (x)
101ECB_HEADER_INLINE int ecb_popcount32 (uint32_t x) { return __builtin_popcount (x); } 105#define ecb_popcount32 (x) __builtin_popcount (x)
102#else 106#else
107ECB_HEADER_INLINE int ecb_ctz32 (uint32_t x) ecb_const;
103ECB_HEADER_INLINE 108ECB_HEADER_INLINE
104ecb_ctz32 (uint32_t x) ecb_const 109ecb_ctz32 (uint32_t x)
105{ 110{
106 int r = 0; 111 int r = 0;
107 112
108 x &= -x; /* this isolates the lowest bit */ 113 x &= -x; /* this isolates the lowest bit */
109 114
… …
114 if (x & 0xffff0000) r += 16; 119 if (x & 0xffff0000) r += 16;
115 120
116 return r; 121 return r;
117} 122}
118 123
124ECB_HEADER_INLINE int ecb_popcount32 (uint32_t x) ecb_const;
119ECB_HEADER_INLINE 125ECB_HEADER_INLINE
120ecb_popcount32 (uint32_t x) ecb_const 126ecb_popcount32 (uint32_t x)
121{ 127{
122 x -= (x >> 1) & 0x55555555; 128 x -= (x >> 1) & 0x55555555;
123 x = ((x >> 2) & 0x33333333) + (x & 0x33333333); 129 x = ((x >> 2) & 0x33333333) + (x & 0x33333333);
124 x = ((x >> 4) + x) & 0x0f0f0f0f; 130 x = ((x >> 4) + x) & 0x0f0f0f0f;
125 x *= 0x01010101; 131 x *= 0x01010101;
126 132
127 return x >> 24; 133 return x >> 24;
128} 134}
129#endif 135#endif
130 136
137#if ECB_GCC_VERSION(4,3)
138# define ecb_bswap32(x) __builtin_bswap32 (x)
139#else
140ECB_HEADER_INLINE uint32_t ecb_bswap32 (uint32_t x) ecb_const;
141ECB_HEADER_INLINE uint32_t
142ecb_bswap32 (uint32_t x)
143{
144 return (x >> 24)
145 | ((x >> 8) & 0x0000ff00)
146 | ((x << 8) & 0x00ff0000)
147 | (x << 24);
148}
149#endif
150
151#if ECB_GCC_VERSION(4,5)
152# define ecb_unreachable() __builtin_unreachable ()
153#else
154/* this seems to work fine, but gcc always emits a warning for it :/ */
155ECB_HEADER_INLINE void ecb_unreachable (void) ecb_noreturn;
156ECB_HEADER_INLINE void ecb_unreachable (void) { }
157#endif
158
159ECB_HEADER_INLINE unsigned char ecb_byteorder_helper () ecb_const;
131ECB_HEADER_INLINE unsigned char 160ECB_HEADER_INLINE unsigned char
132ecb_byteorder_helper () ecb_const 161ecb_byteorder_helper ()
133{ 162{
134 const uint32_t u = 0x11223344; 163 const uint32_t u = 0x11223344;
135 return *(unsigned char *)&u; 164 return *(unsigned char *)&u;
136} 165}
137 166
167ECB_HEADER_INLINE ecb_bool ecb_big_endian () ecb_const;
138ECB_HEADER_INLINE ecb_bool ecb_big_endian () ecb_const { return ecb_byteorder_helper () == 0x11; }; 168ECB_HEADER_INLINE ecb_bool ecb_big_endian () { return ecb_byteorder_helper () == 0x11; };
169ECB_HEADER_INLINE ecb_bool ecb_little_endian () ecb_const;
139ECB_HEADER_INLINE ecb_bool ecb_little_endian () ecb_const { return ecb_byteorder_helper () == 0x44; }; 170ECB_HEADER_INLINE ecb_bool ecb_little_endian () { return ecb_byteorder_helper () == 0x44; };
140 171
141#if ecb_cplusplus_does_not_suck 172#if ecb_cplusplus_does_not_suck
142// does not work for local types (http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2008/n2657.htm) 173// does not work for local types (http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2008/n2657.htm)
143template<typename T, int N> 174template<typename T, int N>
144static inline int ecb_array_length (const T (&arr)[N]) 175static inline int ecb_array_length (const T (&arr)[N])
… …
147} 178}
148#else 179#else
149#define ecb_array_length(name) (sizeof (name) / sizeof (name [0])) 180#define ecb_array_length(name) (sizeof (name) / sizeof (name [0]))
150#endif 181#endif
151 182
183ECB_INLINE uint32_t ecb_rotr32 (uint32_t x, unsigned int count) ecb_const;
152ECB_INLINE uint32_t 184ECB_INLINE uint32_t
153ecb_rotr32 (uint32_t x, unsigned int count) 185ecb_rotr32 (uint32_t x, unsigned int count)
154{ 186{
155 return (x << (32 - count)) | (x >> count); 187 return (x << (32 - count)) | (x >> count);
156} 188}
157 189
190ECB_INLINE uint32_t ecb_rotl32 (uint32_t x, unsigned int count) ecb_const;
158ECB_INLINE uint32_t 191ECB_INLINE uint32_t
159ecb_rotl32 (uint32_t x, unsigned int count) 192ecb_rotl32 (uint32_t x, unsigned int count)
160{ 193{
161 return (x >> (32 - count)) | (x << count); 194 return (x >> (32 - count)) | (x << count);
162} 195}
163 196
164#if ECB_GCC_VERSION(4,3)
165# define ecb_bswap32(x) __builtin_bswap32 (x)
166#else
167ECB_GCC_VERSION uint32_t
168ecb_bswap32 (uint32_t x)
169{
170 return (x >> 24)
171 | ((x >> 8) & 0x0000ff00)
172 | ((x << 8) & 0x00ff0000)
173 | (x << 24);
174}
175#endif 197#endif
176 198
177#endif
178

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