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Comparing libecb/ecb.h (file contents):
Revision 1.3 by root, Thu May 26 16:57:04 2011 UTC vs.
Revision 1.32 by root, Wed Jun 1 01:02:31 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 <libecb@schmorp.de>
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
50#ifndef __cplusplus
51# if __STDC_VERSION__ >= 199901L
52# define ECB_INLINE inline
53typedef _Bool ecb_bool;
54# else
55# define ECB_INLINE inline /* yeah! */
56typedef int ecb_bool;
57# endif
58#else
59# define ECB_INLINE inline
60typedef bool ecb_bool;
61#endif
62
63#define ECB_CONCAT_(a, b) a ## b
64#define ECB_CONCAT(a, b) ECB_CONCAT_(a, b)
65#define ECB_STRINGIFY_(a) # a
66#define ECB_STRINGIFY(a) ECB_STRINGIFY_(a)
67
34#define ECB_HEADER_INLINE static inline 68#define ECB_HEADER_INLINE static ECB_INLINE
35 69
36#if ECB_GCC_VERSION(3,1) 70#if ECB_GCC_VERSION(3,1)
37# define ecb_attribute(attrlist) __attribute__(attrlist) 71# define ecb_attribute(attrlist) __attribute__(attrlist)
38# define ecb_is_constant(c) __builtin_constant_p (c) 72# define ecb_is_constant(expr) __builtin_constant_p (expr)
39# define ecb_expect(expr,value) __builtin_expect ((expr),(value)) 73# define ecb_expect(expr,value) __builtin_expect ((expr),(value))
40# define ecb_prefetch(addr,rw,locality) __builtin_prefetch (addr, rw, locality) 74# define ecb_prefetch(addr,rw,locality) __builtin_prefetch (addr, rw, locality)
41#else 75#else
42# define ecb_attribute(attrlist) 76# define ecb_attribute(attrlist)
43# define ecb_is_constant(c) 0 77# define ecb_is_constant(expr) 0
44# define ecb_expect(expr,value) (expr) 78# define ecb_expect(expr,value) (expr)
45# define ecb_prefetch(addr,rw,locality) 79# define ecb_prefetch(addr,rw,locality)
46#endif 80#endif
47 81
48/* no emulation for ecb_decltype */ 82/* no emulation for ecb_decltype */
… …
50# define ecb_decltype(x) __decltype(x) 84# define ecb_decltype(x) __decltype(x)
51#elif ECB_GCC_VERSION(3,0) 85#elif ECB_GCC_VERSION(3,0)
52# define ecb_decltype(x) typeof(x) 86# define ecb_decltype(x) typeof(x)
53#endif 87#endif
54 88
89#define ecb_artificial ecb_attribute ((__artificial__)) /* 4.3 */
55#define ecb_noinline ecb_attribute ((noinline)) 90#define ecb_noinline ecb_attribute ((__noinline__))
56#define ecb_noreturn ecb_attribute ((noreturn)) 91#define ecb_noreturn ecb_attribute ((__noreturn__))
57#define ecb_unused ecb_attribute ((unused)) 92#define ecb_unused ecb_attribute ((__unused__))
58#define ecb_const ecb_attribute ((const)) 93#define ecb_const ecb_attribute ((__const__))
59#define ecb_pure ecb_attribute ((pure)) 94#define ecb_pure ecb_attribute ((__pure__))
60#define ecb_hot ecb_attribute ((hot)) // 4.3 95#define ecb_hot ecb_attribute ((__hot__)) /* 4.3 */
61#define ecb_cold ecb_attribute ((cold)) // 4.3 96#define ecb_cold ecb_attribute ((__cold__)) /* 4.3 */
62 97
63#if ECB_GCC_VERSION(4,5)
64# define ecb_unreachable() __builtin_unreachable ()
65#else
66 /* this seems to work fine, but gcc always emits a warning for it :/ */
67 ECB_HEADER_INLINE void ecb_unreachable () ecb_attribute ((noreturn));
68 ECB_HEADER_INLINE void ecb_unreachable () { }
69#endif
70
71/* put into ifs if you are very sure that the expression */ 98/* put into if's if you are very sure that the expression */
72/* is mostly true or mosty false. note that these return */ 99/* is mostly true or mosty false. note that these return */
73/* booleans, not the expression. */ 100/* booleans, not the expression. */
74#define ecb_expect_false(expr) ecb_expect ((expr) ? 1 : 0, 0) 101#define ecb_unlikely(expr) ecb_expect (!!(expr), 0)
75#define ecb_expect_true(expr) ecb_expect ((expr) ? 1 : 0, 1) 102#define ecb_likely(expr) ecb_expect (!!(expr), 1)
76 103
77/* try to tell the compiler that some condition is definitely true */ 104/* try to tell the compiler that some condition is definitely true */
78#define ecb_assume(cond) do { if (!(cond)) unreachable (); } while (0) 105#define ecb_assume(cond) do { if (!(cond)) ecb_unreachable (); } while (0)
79 106
80/* count trailing zero bits and count # of one bits */ 107/* count trailing zero bits and count # of one bits */
81#if ECB_GCC_VERSION(3,4) 108#if ECB_GCC_VERSION(3,4)
82ECB_HEADER_INLINE int ecb_ctz (unsigned int x) { return __builtin_ctz (x); } 109#define ecb_ctz32(x) __builtin_ctz (x)
83ECB_HEADER_INLINE int ecb_popcount (unsigned int x) { return __builtin_popcount (x); } 110#define ecb_popcount32(x) __builtin_popcount (x)
84#else 111#else
112ECB_HEADER_INLINE int ecb_ctz32 (uint32_t x) ecb_const;
85ECB_HEADER_INLINE 113ECB_HEADER_INLINE
86ecb_ctz (unsigned int x) ecb_const 114ecb_ctz32 (uint32_t x)
87{ 115{
88 int r = 0; 116 int r = 0;
89 117
90 x &= -x; // this isolates the lowest bit 118 x &= -x; /* this isolates the lowest bit */
91 119
92 if (x & 0xaaaaaaaa) r += 1; 120 if (x & 0xaaaaaaaa) r += 1;
93 if (x & 0xcccccccc) r += 2; 121 if (x & 0xcccccccc) r += 2;
94 if (x & 0xf0f0f0f0) r += 4; 122 if (x & 0xf0f0f0f0) r += 4;
95 if (x & 0xff00ff00) r += 8; 123 if (x & 0xff00ff00) r += 8;
96 if (x & 0xffff0000) r += 16; 124 if (x & 0xffff0000) r += 16;
97 125
98 return r; 126 return r;
99} 127}
100 128
129ECB_HEADER_INLINE int ecb_popcount32 (uint32_t x) ecb_const;
101ECB_HEADER_INLINE 130ECB_HEADER_INLINE
102ecb_popcount (unsigned int x) ecb_const 131ecb_popcount32 (uint32_t x)
103{ 132{
104 x -= (x >> 1) & 0x55555555; 133 x -= (x >> 1) & 0x55555555;
105 x = ((x >> 2) & 0x33333333) + (x & 0x33333333); 134 x = ((x >> 2) & 0x33333333) + (x & 0x33333333);
106 x = ((x >> 4) + x) & 0x0f0f0f0f; 135 x = ((x >> 4) + x) & 0x0f0f0f0f;
107 x *= 0x01010101; 136 x *= 0x01010101;
108 137
109 return x >> 24; 138 return x >> 24;
110} 139}
111#endif 140#endif
112 141
142#if ECB_GCC_VERSION(4,3)
143# define ecb_bswap32(x) __builtin_bswap32 (x)
144# define ecb_bswap16(x) (__builtin_bswap32(x) >> 16)
145#else
146ECB_HEADER_INLINE uint32_t ecb_bswap32 (uint32_t x) ecb_const;
147ECB_HEADER_INLINE uint32_t
148ecb_bswap32 (uint32_t x)
149{
150 return (x >> 24)
151 | ((x >> 8) & 0x0000ff00)
152 | ((x << 8) & 0x00ff0000)
153 | (x << 24);
154}
155
156ECB_HEADER_INLINE uint32_t ecb_bswap16 (uint32_t x) ecb_const;
157ECB_HEADER_INLINE uint32_t
158ecb_bswap16 (uint32_t x)
159{
160 return ((x >> 8) & 0xff)
161 | ((x << 8) & 0x00ff0000)
162 | (x << 24);
163}
164#endif
165
166#if ECB_GCC_VERSION(4,5)
167# define ecb_unreachable() __builtin_unreachable ()
168#else
169/* this seems to work fine, but gcc always emits a warning for it :/ */
170ECB_HEADER_INLINE void ecb_unreachable (void) ecb_noreturn;
171ECB_HEADER_INLINE void ecb_unreachable (void) { }
172#endif
173
174ECB_HEADER_INLINE unsigned char ecb_byteorder_helper (void) ecb_const;
113ECB_HEADER_INLINE unsigned char 175ECB_HEADER_INLINE unsigned char
114ecb_byteorder_helper () ecb_const 176ecb_byteorder_helper (void)
115{ 177{
116 const uint32_t u = 0x11223344; 178 const uint32_t u = 0x11223344;
117 return *(unsigned char *)&u; 179 return *(unsigned char *)&u;
118} 180}
119 181
182ECB_HEADER_INLINE ecb_bool ecb_big_endian (void) ecb_const;
120ECB_HEADER_INLINE bool ecb_big_endian () ecb_const { return ecb_byteorder_helper () == 0x11; }; 183ECB_HEADER_INLINE ecb_bool ecb_big_endian (void) { return ecb_byteorder_helper () == 0x11; };
121ECB_HEADER_INLINE bool ecb_network () ecb_const { return big_endian (); }; 184ECB_HEADER_INLINE ecb_bool ecb_little_endian (void) ecb_const;
122ECB_HEADER_INLINE bool ecb_little_endian () ecb_const { return ecb_byteorder_helper () == 0x44; }; 185ECB_HEADER_INLINE ecb_bool ecb_little_endian (void) { return ecb_byteorder_helper () == 0x44; };
123ECB_HEADER_INLINE bool ecb_vax () ecb_const { return little_endian (); };
124 186
125 187#if ECB_GCC_VERSION(3,0)
188# define ecb_mod(m,n) ((m) % (n) + ((m) % (n) < 0 ? (n) : 0))
189#else
190# define ecb_mod(m,n) ((m) < 0 ? ((n) - 1 - ((-1 - (m)) % (n))) : ((m) % (n)))
126#endif 191#endif
127 192
193#if ecb_cplusplus_does_not_suck
194// does not work for local types (http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2008/n2657.htm)
195template<typename T, int N>
196static inline int ecb_array_length (const T (&arr)[N])
197{
198 return N;
199}
200#else
201#define ecb_array_length(name) (sizeof (name) / sizeof (name [0]))
202#endif
203
204ECB_INLINE uint32_t ecb_rotr32 (uint32_t x, unsigned int count) ecb_const;
205ECB_INLINE uint32_t
206ecb_rotr32 (uint32_t x, unsigned int count)
207{
208 return (x << (32 - count)) | (x >> count);
209}
210
211ECB_INLINE uint32_t ecb_rotl32 (uint32_t x, unsigned int count) ecb_const;
212ECB_INLINE uint32_t
213ecb_rotl32 (uint32_t x, unsigned int count)
214{
215 return (x >> (32 - count)) | (x << count);
216}
217
218#endif
219

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