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Comparing libecb/ecb.h (file contents):
Revision 1.1 by root, Thu May 26 16:41:12 2011 UTC vs.
Revision 1.26 by sf-exg, Thu May 26 21:35:39 2011 UTC

1/* 1/*
2 * libecb 2 * libecb - http://software.schmorp.de/pkg/libecb
3 * 3 *
4 * Copyright (c) 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
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#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)
64
65#define ECB_HEADER_INLINE static ECB_INLINE
33 66
34#if ECB_GCC_VERSION(3,1) 67#if ECB_GCC_VERSION(3,1)
35# define ecb_attribute(attrlist) __attribute__(attrlist) 68# define ecb_attribute(attrlist) __attribute__(attrlist)
36# define ecb_is_constant(c) __builtin_constant_p (c) 69# define ecb_is_constant(expr) __builtin_constant_p (expr)
37# define ecb_expect(expr,value) __builtin_expect ((expr),(value)) 70# define ecb_expect(expr,value) __builtin_expect ((expr),(value))
38# define ecb_prefetch(addr,rw,locality) __builtin_prefetch (addr, rw, locality) 71# define ecb_prefetch(addr,rw,locality) __builtin_prefetch (addr, rw, locality)
39#else 72#else
40# define ecb_attribute(attrlist) 73# define ecb_attribute(attrlist)
41# define ecb_is_constant(c) 0 74# define ecb_is_constant(expr) 0
42# define ecb_expect(expr,value) (expr) 75# define ecb_expect(expr,value) (expr)
43# define ecb_prefetch(addr,rw,locality) 76# define ecb_prefetch(addr,rw,locality)
44#endif 77#endif
45 78
79/* no emulation for ecb_decltype */
46#if ECB_GCC_VERSION(4,5) 80#if ECB_GCC_VERSION(4,5)
47# define ecb_decltype(x) __decltype(x) 81# define ecb_decltype(x) __decltype(x)
48#elif ECB_GCC_VERSION(3,0) 82#elif ECB_GCC_VERSION(3,0)
49# define ecb_decltype(x) typeof(x) 83# define ecb_decltype(x) typeof(x)
50#endif 84#endif
51 85
86#define ecb_artificial ecb_attribute ((__artificial__)) /* 4.3 */
52#define ecb_noinline ecb_attribute ((noinline)) 87#define ecb_noinline ecb_attribute ((__noinline__))
53#define ecb_noreturn ecb_attribute ((noreturn)) 88#define ecb_noreturn ecb_attribute ((__noreturn__))
54#define ecb_unused ecb_attribute ((unused)) 89#define ecb_unused ecb_attribute ((__unused__))
55#define ecb_const ecb_attribute ((const)) 90#define ecb_const ecb_attribute ((__const__))
56#define ecb_pure ecb_attribute ((pure)) 91#define ecb_pure ecb_attribute ((__pure__))
57#define ecb_hot ecb_attribute ((hot)) // 4.3 92#define ecb_hot ecb_attribute ((__hot__)) /* 4.3 */
58#define ecb_cold ecb_attribute ((cold)) // 4.3 93#define ecb_cold ecb_attribute ((__cold__)) /* 4.3 */
59 94
60#if ECB_GCC_VERSION(4,5)
61# define ecb_unreachable() __builtin_unreachable ()
62#else
63 // this seems to work fine, but gcc always emits a warning for it :/
64 static inline void ecb_unreachable () ecb_attribute ((noreturn));
65 static inline void ecb_unreachable () { }
66#endif
67
68// put into ifs if you are very sure that the expression 95/* put into if's if you are very sure that the expression */
69// is mostly true or mosty false. note that these return 96/* is mostly true or mosty false. note that these return */
70// booleans, not the expression. 97/* booleans, not the expression. */
71#define ecb_expect_false(expr) ecb_expect ((expr) ? 1 : 0, 0) 98#define ecb_unlikely(expr) ecb_expect (!!(expr), 0)
72#define ecb_expect_true(expr) ecb_expect ((expr) ? 1 : 0, 1) 99#define ecb_likely(expr) ecb_expect (!!(expr), 1)
73 100
74// try to tell the compiler that some condition is definitely true 101/* try to tell the compiler that some condition is definitely true */
75#define ecb_assume(cond) do { if (!(cond)) unreachable (); } while (0) 102#define ecb_assume(cond) do { if (!(cond)) ecb_unreachable (); } while (0)
76 103
77// count trailing zero bits and count # of one bits 104/* count trailing zero bits and count # of one bits */
78#if ECB_GCC_VERSION(3,4) 105#if ECB_GCC_VERSION(3,4)
79static inline int ecb_ctz (unsigned int x) { return __builtin_ctz (x); } 106#define ecb_ctz32(x) __builtin_ctz (x)
80static inline int ecb_popcount (unsigned int x) { return __builtin_popcount (x); } 107#define ecb_popcount32(x) __builtin_popcount (x)
81#else 108#else
82static int ecb_ctz (unsigned int x) ecb_const 109ECB_HEADER_INLINE int ecb_ctz32 (uint32_t x) ecb_const;
110ECB_HEADER_INLINE
111ecb_ctz32 (uint32_t x)
83{ 112{
84 int r = 0; 113 int r = 0;
85 114
86 x &= -x; // this isolates the lowest bit 115 x &= -x; /* this isolates the lowest bit */
87 116
88 if (x & 0xaaaaaaaa) r += 1; 117 if (x & 0xaaaaaaaa) r += 1;
89 if (x & 0xcccccccc) r += 2; 118 if (x & 0xcccccccc) r += 2;
90 if (x & 0xf0f0f0f0) r += 4; 119 if (x & 0xf0f0f0f0) r += 4;
91 if (x & 0xff00ff00) r += 8; 120 if (x & 0xff00ff00) r += 8;
92 if (x & 0xffff0000) r += 16; 121 if (x & 0xffff0000) r += 16;
93 122
94 return r; 123 return r;
95} 124}
96 125
97static int ecb_popcount (unsigned int x) ecb_const 126ECB_HEADER_INLINE int ecb_popcount32 (uint32_t x) ecb_const;
127ECB_HEADER_INLINE
128ecb_popcount32 (uint32_t x)
98{ 129{
99 x -= (x >> 1) & 0x55555555; 130 x -= (x >> 1) & 0x55555555;
100 x = ((x >> 2) & 0x33333333) + (x & 0x33333333); 131 x = ((x >> 2) & 0x33333333) + (x & 0x33333333);
101 x = ((x >> 4) + x) & 0x0f0f0f0f; 132 x = ((x >> 4) + x) & 0x0f0f0f0f;
102 x *= 0x01010101; 133 x *= 0x01010101;
103 134
104 return x >> 24; 135 return x >> 24;
105} 136}
106#endif 137#endif
107 138
108#endif 139#if ECB_GCC_VERSION(4,3)
140# define ecb_bswap32(x) __builtin_bswap32 (x)
141# define ecb_bswap16(x) (__builtin_bswap32(x) >> 16)
142#else
143ECB_HEADER_INLINE uint32_t ecb_bswap32 (uint32_t x) ecb_const;
144ECB_HEADER_INLINE uint32_t
145ecb_bswap32 (uint32_t x)
146{
147 return (x >> 24)
148 | ((x >> 8) & 0x0000ff00)
149 | ((x << 8) & 0x00ff0000)
150 | (x << 24);
151}
109 152
153ECB_HEADER_INLINE uint32_t ecb_bswap16 (uint32_t x) ecb_const;
154ECB_HEADER_INLINE uint32_t
155ecb_bswap16 (uint32_t x)
156{
157 return ((x >> 8) & 0xff)
158 | ((x << 8) & 0x00ff0000)
159 | (x << 24);
160}
161#endif
162
163#if ECB_GCC_VERSION(4,5)
164# define ecb_unreachable() __builtin_unreachable ()
165#else
166/* this seems to work fine, but gcc always emits a warning for it :/ */
167ECB_HEADER_INLINE void ecb_unreachable (void) ecb_noreturn;
168ECB_HEADER_INLINE void ecb_unreachable (void) { }
169#endif
170
171ECB_HEADER_INLINE unsigned char ecb_byteorder_helper (void) ecb_const;
172ECB_HEADER_INLINE unsigned char
173ecb_byteorder_helper (void)
174{
175 const uint32_t u = 0x11223344;
176 return *(unsigned char *)&u;
177}
178
179ECB_HEADER_INLINE ecb_bool ecb_big_endian (void) ecb_const;
180ECB_HEADER_INLINE ecb_bool ecb_big_endian (void) { return ecb_byteorder_helper () == 0x11; };
181ECB_HEADER_INLINE ecb_bool ecb_little_endian (void) ecb_const;
182ECB_HEADER_INLINE ecb_bool ecb_little_endian (void) { return ecb_byteorder_helper () == 0x44; };
183
184#define ecb_mod(m, n) ((m) < 0 ? ((n) - (-(m) % (n))) : ((m) % (n)))
185
186#if ecb_cplusplus_does_not_suck
187// does not work for local types (http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2008/n2657.htm)
188template<typename T, int N>
189static inline int ecb_array_length (const T (&arr)[N])
190{
191 return N;
192}
193#else
194#define ecb_array_length(name) (sizeof (name) / sizeof (name [0]))
195#endif
196
197ECB_INLINE uint32_t ecb_rotr32 (uint32_t x, unsigned int count) ecb_const;
198ECB_INLINE uint32_t
199ecb_rotr32 (uint32_t x, unsigned int count)
200{
201 return (x << (32 - count)) | (x >> count);
202}
203
204ECB_INLINE uint32_t ecb_rotl32 (uint32_t x, unsigned int count) ecb_const;
205ECB_INLINE uint32_t
206ecb_rotl32 (uint32_t x, unsigned int count)
207{
208 return (x >> (32 - count)) | (x << count);
209}
210
211#endif
212

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