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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 1.37 by root, Sat Jun 11 13:47:47 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 <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
49
50#ifndef __cplusplus
51 #if __STDC_VERSION__ >= 199901L
52 #define ECB_INLINE static inline
53 typedef _Bool ecb_bool;
54 #else
55 #define ECB_INLINE static inline /* we assume the extension is ubiquituous, please tell us when we are wrong, or upgrade to the GCC */
56 typedef int ecb_bool;
57 #endif
58#else
59 #define ECB_INLINE static inline
60 typedef 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
68#define ECB_HEADER_INLINE ECB_INLINE
33 69
34#if ECB_GCC_VERSION(3,1) 70#if ECB_GCC_VERSION(3,1)
35# define ecb_attribute(attrlist) __attribute__(attrlist) 71 #define ecb_attribute(attrlist) __attribute__(attrlist)
36# define ecb_is_constant(c) __builtin_constant_p (c) 72 #define ecb_is_constant(expr) __builtin_constant_p (expr)
37# define ecb_expect(expr,value) __builtin_expect ((expr),(value)) 73 #define ecb_expect(expr,value) __builtin_expect ((expr),(value))
38# define ecb_prefetch(addr,rw,locality) __builtin_prefetch (addr, rw, locality) 74 #define ecb_prefetch(addr,rw,locality) __builtin_prefetch (addr, rw, locality)
39#else 75#else
40# define ecb_attribute(attrlist) 76 #define ecb_attribute(attrlist)
41# define ecb_is_constant(c) 0 77 #define ecb_is_constant(expr) 0
42# define ecb_expect(expr,value) (expr) 78 #define ecb_expect(expr,value) (expr)
43# define ecb_prefetch(addr,rw,locality) 79 #define ecb_prefetch(addr,rw,locality)
44#endif 80#endif
45 81
82/* no emulation for ecb_decltype */
46#if ECB_GCC_VERSION(4,5) 83#if ECB_GCC_VERSION(4,5)
47# define ecb_decltype(x) __decltype(x) 84 #define ecb_decltype(x) __decltype(x)
48#elif ECB_GCC_VERSION(3,0) 85#elif ECB_GCC_VERSION(3,0)
49# define ecb_decltype(x) typeof(x) 86 #define ecb_decltype(x) typeof(x)
50#endif 87#endif
51 88
52#define ecb_noinline ecb_attribute ((noinline)) 89#define ecb_noinline ecb_attribute ((__noinline__))
53#define ecb_noreturn ecb_attribute ((noreturn)) 90#define ecb_noreturn ecb_attribute ((__noreturn__))
54#define ecb_unused ecb_attribute ((unused)) 91#define ecb_unused ecb_attribute ((__unused__))
55#define ecb_const ecb_attribute ((const)) 92#define ecb_const ecb_attribute ((__const__))
56#define ecb_pure ecb_attribute ((pure)) 93#define ecb_pure ecb_attribute ((__pure__))
94
95#if ECB_GCC_VERSION(4,3)
96 #define ecb_artificial ecb_attribute ((__artificial__)) /* 4.3 */
57#define ecb_hot ecb_attribute ((hot)) // 4.3 97 #define ecb_hot ecb_attribute ((__hot__)) /* 4.3 */
58#define ecb_cold ecb_attribute ((cold)) // 4.3 98 #define ecb_cold ecb_attribute ((__cold__)) /* 4.3 */
99#else
100 #define ecb_artificial
101 #define ecb_hot
102 #define ecb_cold
103#endif
104
105/* put into if's if you are very sure that the expression */
106/* is mostly true or mostly false. note that these return */
107/* booleans, not the expression. */
108#define ecb_expect_false(expr) ecb_expect (!!(expr), 0)
109#define ecb_expect_true(expr) ecb_expect (!!(expr), 1)
110/* for compatibility to the rest of the world */
111#define ecb_likely(expr) ecb_expect_true (expr)
112#define ecb_unlikely(expr) ecb_expect_false (expr)
113
114/* try to tell the compiler that some condition is definitely true */
115#define ecb_assume(cond) do { if (!(cond)) ecb_unreachable (); } while (0)
116
117/* count trailing zero bits and count # of one bits */
118#if ECB_GCC_VERSION(3,4)
119 #define ecb_ctz32(x) __builtin_ctz (x)
120 #define ecb_popcount32(x) __builtin_popcount (x)
121#else
122 ECB_HEADER_INLINE int ecb_ctz32 (uint32_t x) ecb_const;
123 ECB_HEADER_INLINE int
124 ecb_ctz32 (uint32_t x)
125 {
126 int r = 0;
127
128 x &= -x; /* this isolates the lowest bit */
129
130 if (x & 0xaaaaaaaa) r += 1;
131 if (x & 0xcccccccc) r += 2;
132 if (x & 0xf0f0f0f0) r += 4;
133 if (x & 0xff00ff00) r += 8;
134 if (x & 0xffff0000) r += 16;
135
136 return r;
137 }
138
139 ECB_HEADER_INLINE int ecb_popcount32 (uint32_t x) ecb_const;
140 ECB_HEADER_INLINE int
141 ecb_popcount32 (uint32_t x)
142 {
143 x -= (x >> 1) & 0x55555555;
144 x = ((x >> 2) & 0x33333333) + (x & 0x33333333);
145 x = ((x >> 4) + x) & 0x0f0f0f0f;
146 x *= 0x01010101;
147
148 return x >> 24;
149 }
150#endif
151
152#if ECB_GCC_VERSION(4,3)
153 #define ecb_bswap32(x) __builtin_bswap32 (x)
154 #define ecb_bswap16(x) (__builtin_bswap32(x) >> 16)
155#else
156 ECB_HEADER_INLINE uint32_t ecb_bswap32 (uint32_t x) ecb_const;
157 ECB_HEADER_INLINE uint32_t
158 ecb_bswap32 (uint32_t x)
159 {
160 return (x >> 24)
161 | ((x >> 8) & 0x0000ff00)
162 | ((x << 8) & 0x00ff0000)
163 | (x << 24);
164 }
165
166 ECB_HEADER_INLINE uint32_t ecb_bswap16 (uint32_t x) ecb_const;
167 ECB_HEADER_INLINE uint32_t
168 ecb_bswap16 (uint32_t x)
169 {
170 return ((x >> 8) & 0xff)
171 | ((x << 8) & 0x00ff0000)
172 | (x << 24);
173 }
174#endif
59 175
60#if ECB_GCC_VERSION(4,5) 176#if ECB_GCC_VERSION(4,5)
61# define ecb_unreachable() __builtin_unreachable () 177 #define ecb_unreachable() __builtin_unreachable ()
62#else 178#else
63 // this seems to work fine, but gcc always emits a warning for it :/ 179 /* this seems to work fine, but gcc always emits a warning for it :/ */
64 static inline void ecb_unreachable () ecb_attribute ((noreturn)); 180 ECB_HEADER_INLINE void ecb_unreachable (void) ecb_noreturn;
65 static inline void ecb_unreachable () { } 181 ECB_HEADER_INLINE void ecb_unreachable (void) { }
66#endif 182#endif
67 183
68// put into ifs if you are very sure that the expression 184ECB_HEADER_INLINE unsigned char ecb_byteorder_helper (void) ecb_const;
69// is mostly true or mosty false. note that these return 185ECB_HEADER_INLINE unsigned char
70// booleans, not the expression. 186ecb_byteorder_helper (void)
71#define ecb_expect_false(expr) ecb_expect ((expr) ? 1 : 0, 0)
72#define ecb_expect_true(expr) ecb_expect ((expr) ? 1 : 0, 1)
73
74// try to tell the compiler that some condition is definitely true
75#define ecb_assume(cond) do { if (!(cond)) unreachable (); } while (0)
76
77// count trailing zero bits and count # of one bits
78#if ECB_GCC_VERSION(3,4)
79static inline int ecb_ctz (unsigned int x) { return __builtin_ctz (x); }
80static inline int ecb_popcount (unsigned int x) { return __builtin_popcount (x); }
81#else
82static int ecb_ctz (unsigned int x) ecb_const
83{ 187{
84 int r = 0; 188 const uint32_t u = 0x11223344;
85 189 return *(unsigned char *)&u;
86 x &= -x; // this isolates the lowest bit
87
88 if (x & 0xaaaaaaaa) r += 1;
89 if (x & 0xcccccccc) r += 2;
90 if (x & 0xf0f0f0f0) r += 4;
91 if (x & 0xff00ff00) r += 8;
92 if (x & 0xffff0000) r += 16;
93
94 return r;
95} 190}
96 191
97static int ecb_popcount (unsigned int x) ecb_const 192ECB_HEADER_INLINE ecb_bool ecb_big_endian (void) ecb_const;
193ECB_HEADER_INLINE ecb_bool ecb_big_endian (void) { return ecb_byteorder_helper () == 0x11; };
194ECB_HEADER_INLINE ecb_bool ecb_little_endian (void) ecb_const;
195ECB_HEADER_INLINE ecb_bool ecb_little_endian (void) { return ecb_byteorder_helper () == 0x44; };
196
197#if ECB_GCC_VERSION(3,0)
198 #define ecb_mod(m,n) ((m) % (n) + ((m) % (n) < 0 ? (n) : 0))
199#else
200 #define ecb_mod(m,n) ((m) < 0 ? ((n) - 1 - ((-1 - (m)) % (n))) : ((m) % (n)))
201#endif
202
203#if ecb_cplusplus_does_not_suck
204 // does not work for local types (http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2008/n2657.htm)
205 template<typename T, int N>
206 static inline int ecb_array_length (const T (&arr)[N])
207 {
208 return N;
209 }
210#else
211 #define ecb_array_length(name) (sizeof (name) / sizeof (name [0]))
212#endif
213
214ECB_INLINE uint32_t ecb_rotr32 (uint32_t x, unsigned int count) ecb_const;
215ECB_INLINE uint32_t
216ecb_rotr32 (uint32_t x, unsigned int count)
98{ 217{
99 x -= (x >> 1) & 0x55555555; 218 return (x << (32 - count)) | (x >> count);
100 x = ((x >> 2) & 0x33333333) + (x & 0x33333333);
101 x = ((x >> 4) + x) & 0x0f0f0f0f;
102 x *= 0x01010101;
103
104 return x >> 24;
105} 219}
106#endif
107 220
108#endif 221ECB_INLINE uint32_t ecb_rotl32 (uint32_t x, unsigned int count) ecb_const;
222ECB_INLINE uint32_t
223ecb_rotl32 (uint32_t x, unsigned int count)
224{
225 return (x >> (32 - count)) | (x << count);
226}
109 227
228#endif
229

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