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Comparing libecb/ecb.h (file contents):
Revision 1.4 by root, Thu May 26 17:26:03 2011 UTC vs.
Revision 1.7 by root, Thu May 26 17:38:25 2011 UTC

1/* 1/*
2 * libecb 2 * libecb
3 * 3 *
4 * Copyright (©) 2009-2011 Marc Alexander Lehmann 4 * Copyright (©) 2009-2011 Marc Alexander Lehmann
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 *
… …
26 * OF THE POSSIBILITY OF SUCH DAMAGE. 27 * OF THE POSSIBILITY OF SUCH DAMAGE.
27 */ 28 */
28 29
29#ifndef ECB_H 30#ifndef ECB_H
30#define ECB_H 31#define ECB_H
32
33#include <inttypes.h>
31 34
32#define ECB_GCC_VERSION(major,minor) (__GNUC__ > (major) || (__GNUC__ == (major) && __GNUC_MINOR__ >= (minor))) 35#define ECB_GCC_VERSION(major,minor) (__GNUC__ > (major) || (__GNUC__ == (major) && __GNUC_MINOR__ >= (minor)))
33 36
34#ifndef __cplusplus 37#ifndef __cplusplus
35# if __STDC_VERSION__ >= 199901L 38# if __STDC_VERSION__ >= 199901L
… …
79#endif 82#endif
80 83
81/* put into ifs if you are very sure that the expression */ 84/* put into ifs if you are very sure that the expression */
82/* is mostly true or mosty false. note that these return */ 85/* is mostly true or mosty false. note that these return */
83/* booleans, not the expression. */ 86/* booleans, not the expression. */
84#define ecb_expect_false(expr) ecb_expect ((expr) ? 1 : 0, 0) 87#define ecb_unlikely(expr) ecb_expect ((expr) ? 1 : 0, 0)
85#define ecb_expect_true(expr) ecb_expect ((expr) ? 1 : 0, 1) 88#define ecb_likely(expr) ecb_expect ((expr) ? 1 : 0, 1)
86 89
87/* try to tell the compiler that some condition is definitely true */ 90/* try to tell the compiler that some condition is definitely true */
88#define ecb_assume(cond) do { if (!(cond)) unreachable (); } while (0) 91#define ecb_assume(cond) do { if (!(cond)) unreachable (); } while (0)
89 92
90/* count trailing zero bits and count # of one bits */ 93/* count trailing zero bits and count # of one bits */
91#if ECB_GCC_VERSION(3,4) 94#if ECB_GCC_VERSION(3,4)
92ECB_HEADER_INLINE int ecb_ctz32 (unsigned int x) { return __builtin_ctz (x); } 95ECB_HEADER_INLINE int ecb_ctz32 (uint32_t x) { return __builtin_ctz (x); }
93ECB_HEADER_INLINE int ecb_popcount32 (unsigned int x) { return __builtin_popcount (x); } 96ECB_HEADER_INLINE int ecb_popcount32 (uint32_t x) { return __builtin_popcount (x); }
94#else 97#else
95ECB_HEADER_INLINE 98ECB_HEADER_INLINE
96ecb_ctz32 (unsigned int x) ecb_const 99ecb_ctz32 (uint32_t x) ecb_const
97{ 100{
98 int r = 0; 101 int r = 0;
99 102
100 x &= -x; /* this isolates the lowest bit */ 103 x &= -x; /* this isolates the lowest bit */
101 104
… …
107 110
108 return r; 111 return r;
109} 112}
110 113
111ECB_HEADER_INLINE 114ECB_HEADER_INLINE
112ecb_popcount32 (unsigned int x) ecb_const 115ecb_popcount32 (uint32_t x) ecb_const
113{ 116{
114 x -= (x >> 1) & 0x55555555; 117 x -= (x >> 1) & 0x55555555;
115 x = ((x >> 2) & 0x33333333) + (x & 0x33333333); 118 x = ((x >> 2) & 0x33333333) + (x & 0x33333333);
116 x = ((x >> 4) + x) & 0x0f0f0f0f; 119 x = ((x >> 4) + x) & 0x0f0f0f0f;
117 x *= 0x01010101; 120 x *= 0x01010101;
… …
128} 131}
129 132
130ECB_HEADER_INLINE ecb_bool ecb_big_endian () ecb_const { return ecb_byteorder_helper () == 0x11; }; 133ECB_HEADER_INLINE ecb_bool ecb_big_endian () ecb_const { return ecb_byteorder_helper () == 0x11; };
131ECB_HEADER_INLINE ecb_bool ecb_little_endian () ecb_const { return ecb_byteorder_helper () == 0x44; }; 134ECB_HEADER_INLINE ecb_bool ecb_little_endian () ecb_const { return ecb_byteorder_helper () == 0x44; };
132 135
136#if ecb_cplusplus_does_not_suck
137// does not work for local types (http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2008/n2657.htm)
138template<typename T, int N>
139static inline int array_length (const T (&arr)[N])
140{
141 return N;
142}
143#else
144#define ecb_array_length(name) (sizeof (name) / sizeof (name [0]))
133#endif 145#endif
134 146
147ECB_INLINE uint32_t
148ecb_rotate32_right (uint32_t c, unsigned int count = 1)
149{
150 return (c << (32 - count)) | (c >> count);
151}
152
153ECB_INLINE uint32_t
154ecb_rotate32_left (uint32_t c, unsigned int count = 1)
155{
156 return (c >> (32 - count)) | (c << count);
157}
158
159#endif
160

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