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Comparing libecb/ecb.h (file contents):
Revision 1.5 by root, Thu May 26 17:27:15 2011 UTC vs.
Revision 1.18 by root, Thu May 26 18:36:43 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 * 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
33#include <inttypes.h>
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 in return for some better fake benchmark numbers.
38 * or so.
39 * we try to detect these and simply assume they are not gcc - if they have
40 * an issue with that they should have done it right in the first place.
41 */
42#ifndef ECB_GCC_VERSION
43# if defined(__INTEL_COMPILER) || defined(__SUNPRO_C) || defined(__llvm__)
44# define ECB_GCC_VERSION(major,minor) 0
45# else
32#define ECB_GCC_VERSION(major,minor) (__GNUC__ > (major) || (__GNUC__ == (major) && __GNUC_MINOR__ >= (minor))) 46# define ECB_GCC_VERSION(major,minor) (__GNUC__ > (major) || (__GNUC__ == (major) && __GNUC_MINOR__ >= (minor)))
47# endif
48#endif
33 49
34#ifndef __cplusplus 50#ifndef __cplusplus
35# if __STDC_VERSION__ >= 199901L 51# if __STDC_VERSION__ >= 199901L
36# define ECB_INLINE inline 52# define ECB_INLINE inline
37typedef _Bool ecb_bool; 53typedef _Bool ecb_bool;
38# else 54# else
39# define ECB_INLINE inline /* yeah! */ 55# define ECB_INLINE inline /* yeah! */
40typedef int ecb_bool; 56typedef int ecb_bool;
41# endif 57# endif
42#endif 58#endif
59
60#define ECB_CONCAT_(a, b) a ## b
61#define ECB_CONCAT(a, b) ECB_CONCAT_(a, b)
62#define ECB_STRINGIFY_(a) # a
63#define ECB_STRINGIFY(a) ECB_STRINGIFY_(a)
43 64
44#define ECB_HEADER_INLINE static ECB_INLINE 65#define ECB_HEADER_INLINE static ECB_INLINE
45 66
46#if ECB_GCC_VERSION(3,1) 67#if ECB_GCC_VERSION(3,1)
47# define ecb_attribute(attrlist) __attribute__(attrlist) 68# define ecb_attribute(attrlist) __attribute__(attrlist)
… …
68#define ecb_const ecb_attribute ((const)) 89#define ecb_const ecb_attribute ((const))
69#define ecb_pure ecb_attribute ((pure)) 90#define ecb_pure ecb_attribute ((pure))
70#define ecb_hot ecb_attribute ((hot)) /* 4.3 */ 91#define ecb_hot ecb_attribute ((hot)) /* 4.3 */
71#define ecb_cold ecb_attribute ((cold)) /* 4.3 */ 92#define ecb_cold ecb_attribute ((cold)) /* 4.3 */
72 93
73#if ECB_GCC_VERSION(4,5)
74# define ecb_unreachable() __builtin_unreachable ()
75#else
76/* this seems to work fine, but gcc always emits a warning for it :/ */
77ECB_HEADER_INLINE void ecb_unreachable () ecb_attribute ((noreturn));
78ECB_HEADER_INLINE void ecb_unreachable () { }
79#endif
80
81/* put into ifs if you are very sure that the expression */ 94/* put into ifs if you are very sure that the expression */
82/* is mostly true or mosty false. note that these return */ 95/* is mostly true or mosty false. note that these return */
83/* booleans, not the expression. */ 96/* booleans, not the expression. */
84#define ecb_expect_false(expr) ecb_expect ((expr) ? 1 : 0, 0) 97#define ecb_unlikely(expr) ecb_expect (!!(expr), 0)
85#define ecb_expect_true(expr) ecb_expect ((expr) ? 1 : 0, 1) 98#define ecb_likely(expr) ecb_expect (!!(expr), 1)
86 99
87/* try to tell the compiler that some condition is definitely true */ 100/* try to tell the compiler that some condition is definitely true */
88#define ecb_assume(cond) do { if (!(cond)) unreachable (); } while (0) 101#define ecb_assume(cond) do { if (!(cond)) unreachable (); } while (0)
89 102
90/* count trailing zero bits and count # of one bits */ 103/* count trailing zero bits and count # of one bits */
91#if ECB_GCC_VERSION(3,4) 104#if ECB_GCC_VERSION(3,4)
92ECB_HEADER_INLINE int ecb_ctz32 (unsigned int x) { return __builtin_ctz (x); } 105#define ecb_ctz32 (x) __builtin_ctz (x)
93ECB_HEADER_INLINE int ecb_popcount32 (unsigned int x) { return __builtin_popcount (x); } 106#define ecb_popcount32 (x) __builtin_popcount (x)
94#else 107#else
108ECB_HEADER_INLINE int ecb_ctz32 (uint32_t x) ecb_const;
95ECB_HEADER_INLINE 109ECB_HEADER_INLINE
96ecb_ctz32 (unsigned int x) ecb_const 110ecb_ctz32 (uint32_t x)
97{ 111{
98 int r = 0; 112 int r = 0;
99 113
100 x &= -x; /* this isolates the lowest bit */ 114 x &= -x; /* this isolates the lowest bit */
101 115
… …
106 if (x & 0xffff0000) r += 16; 120 if (x & 0xffff0000) r += 16;
107 121
108 return r; 122 return r;
109} 123}
110 124
125ECB_HEADER_INLINE int ecb_popcount32 (uint32_t x) ecb_const;
111ECB_HEADER_INLINE 126ECB_HEADER_INLINE
112ecb_popcount32 (unsigned int x) ecb_const 127ecb_popcount32 (uint32_t x)
113{ 128{
114 x -= (x >> 1) & 0x55555555; 129 x -= (x >> 1) & 0x55555555;
115 x = ((x >> 2) & 0x33333333) + (x & 0x33333333); 130 x = ((x >> 2) & 0x33333333) + (x & 0x33333333);
116 x = ((x >> 4) + x) & 0x0f0f0f0f; 131 x = ((x >> 4) + x) & 0x0f0f0f0f;
117 x *= 0x01010101; 132 x *= 0x01010101;
118 133
119 return x >> 24; 134 return x >> 24;
120} 135}
121#endif 136#endif
122 137
138#if ECB_GCC_VERSION(4,3)
139# define ecb_bswap32(x) __builtin_bswap32 (x)
140#else
141ECB_HEADER_INLINE uint32_t ecb_bswap32 (uint32_t x) ecb_const;
142ECB_HEADER_INLINE uint32_t
143ecb_bswap32 (uint32_t x)
144{
145 return (x >> 24)
146 | ((x >> 8) & 0x0000ff00)
147 | ((x << 8) & 0x00ff0000)
148 | (x << 24);
149}
150#endif
151
152#if ECB_GCC_VERSION(4,5)
153# define ecb_unreachable() __builtin_unreachable ()
154#else
155/* this seems to work fine, but gcc always emits a warning for it :/ */
156ECB_HEADER_INLINE void ecb_unreachable (void) ecb_noreturn;
157ECB_HEADER_INLINE void ecb_unreachable (void) { }
158#endif
159
160ECB_HEADER_INLINE unsigned char ecb_byteorder_helper () ecb_const;
123ECB_HEADER_INLINE unsigned char 161ECB_HEADER_INLINE unsigned char
124ecb_byteorder_helper () ecb_const 162ecb_byteorder_helper ()
125{ 163{
126 const uint32_t u = 0x11223344; 164 const uint32_t u = 0x11223344;
127 return *(unsigned char *)&u; 165 return *(unsigned char *)&u;
128} 166}
129 167
168ECB_HEADER_INLINE ecb_bool ecb_big_endian () ecb_const;
130ECB_HEADER_INLINE ecb_bool ecb_big_endian () ecb_const { return ecb_byteorder_helper () == 0x11; }; 169ECB_HEADER_INLINE ecb_bool ecb_big_endian () { return ecb_byteorder_helper () == 0x11; };
170ECB_HEADER_INLINE ecb_bool ecb_little_endian () ecb_const;
131ECB_HEADER_INLINE ecb_bool ecb_little_endian () ecb_const { return ecb_byteorder_helper () == 0x44; }; 171ECB_HEADER_INLINE ecb_bool ecb_little_endian () { return ecb_byteorder_helper () == 0x44; };
132 172
133#if ecb_cplusplus_does_not_suck 173#if ecb_cplusplus_does_not_suck
134// does not work for local types (http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2008/n2657.htm) 174// does not work for local types (http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2008/n2657.htm)
135template<typename T, int N> 175template<typename T, int N>
136static inline int array_length (const T (&arr)[N]) 176static inline int ecb_array_length (const T (&arr)[N])
137{ 177{
138 return N; 178 return N;
139} 179}
140#else 180#else
141#define ecb_array_length(name) (sizeof (name) / sizeof (name [0])) 181#define ecb_array_length(name) (sizeof (name) / sizeof (name [0]))
142#endif 182#endif
143 183
184ECB_INLINE uint32_t ecb_rotr32 (uint32_t x, unsigned int count) ecb_const;
185ECB_INLINE uint32_t
186ecb_rotr32 (uint32_t x, unsigned int count)
187{
188 return (x << (32 - count)) | (x >> count);
189}
190
191ECB_INLINE uint32_t ecb_rotl32 (uint32_t x, unsigned int count) ecb_const;
192ECB_INLINE uint32_t
193ecb_rotl32 (uint32_t x, unsigned int count)
194{
195 return (x >> (32 - count)) | (x << count);
196}
197
144#endif 198#endif
145 199

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