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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 1.34 by root, Fri Jun 10 12:20:14 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
53typedef _Bool ecb_bool;
54# else
55# define ECB_INLINE static inline /* yeah! */
56typedef int ecb_bool;
57# endif
58#else
59# define ECB_INLINE static 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
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
89#define ecb_artificial ecb_attribute ((__artificial__)) /* 4.3 */
52#define ecb_noinline ecb_attribute ((noinline)) 90#define ecb_noinline ecb_attribute ((__noinline__))
53#define ecb_noreturn ecb_attribute ((noreturn)) 91#define ecb_noreturn ecb_attribute ((__noreturn__))
54#define ecb_unused ecb_attribute ((unused)) 92#define ecb_unused ecb_attribute ((__unused__))
55#define ecb_const ecb_attribute ((const)) 93#define ecb_const ecb_attribute ((__const__))
56#define ecb_pure ecb_attribute ((pure)) 94#define ecb_pure ecb_attribute ((__pure__))
57#define ecb_hot ecb_attribute ((hot)) // 4.3 95#define ecb_hot ecb_attribute ((__hot__)) /* 4.3 */
58#define ecb_cold ecb_attribute ((cold)) // 4.3 96#define ecb_cold ecb_attribute ((__cold__)) /* 4.3 */
59 97
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 98/* put into if's if you are very sure that the expression */
69// is mostly true or mosty false. note that these return 99/* is mostly true or mostly false. note that these return */
70// booleans, not the expression. 100/* booleans, not the expression. */
71#define ecb_expect_false(expr) ecb_expect ((expr) ? 1 : 0, 0) 101#define ecb_expect_false(expr) ecb_expect (!!(expr), 0)
72#define ecb_expect_true(expr) ecb_expect ((expr) ? 1 : 0, 1) 102#define ecb_expect_true(expr) ecb_expect (!!(expr), 1)
103#define ecb_likely(expr) ecb_expect_true (expr)
104#define ecb_unlikely(expr) ecb_expect_false (expr)
73 105
74// try to tell the compiler that some condition is definitely true 106/* try to tell the compiler that some condition is definitely true */
75#define ecb_assume(cond) do { if (!(cond)) unreachable (); } while (0) 107#define ecb_assume(cond) do { if (!(cond)) ecb_unreachable (); } while (0)
76 108
77// count trailing zero bits and count # of one bits 109/* count trailing zero bits and count # of one bits */
78#if ECB_GCC_VERSION(3,4) 110#if ECB_GCC_VERSION(3,4)
79static inline int ecb_ctz (unsigned int x) { return __builtin_ctz (x); } 111#define ecb_ctz32(x) __builtin_ctz (x)
80static inline int ecb_popcount (unsigned int x) { return __builtin_popcount (x); } 112#define ecb_popcount32(x) __builtin_popcount (x)
81#else 113#else
82static int ecb_ctz (unsigned int x) ecb_const 114ECB_HEADER_INLINE int ecb_ctz32 (uint32_t x) ecb_const;
115ECB_HEADER_INLINE int
116ecb_ctz32 (uint32_t x)
83{ 117{
84 int r = 0; 118 int r = 0;
85 119
86 x &= -x; // this isolates the lowest bit 120 x &= -x; /* this isolates the lowest bit */
87 121
88 if (x & 0xaaaaaaaa) r += 1; 122 if (x & 0xaaaaaaaa) r += 1;
89 if (x & 0xcccccccc) r += 2; 123 if (x & 0xcccccccc) r += 2;
90 if (x & 0xf0f0f0f0) r += 4; 124 if (x & 0xf0f0f0f0) r += 4;
91 if (x & 0xff00ff00) r += 8; 125 if (x & 0xff00ff00) r += 8;
92 if (x & 0xffff0000) r += 16; 126 if (x & 0xffff0000) r += 16;
93 127
94 return r; 128 return r;
95} 129}
96 130
97static int ecb_popcount (unsigned int x) ecb_const 131ECB_HEADER_INLINE int ecb_popcount32 (uint32_t x) ecb_const;
132ECB_HEADER_INLINE int
133ecb_popcount32 (uint32_t x)
98{ 134{
99 x -= (x >> 1) & 0x55555555; 135 x -= (x >> 1) & 0x55555555;
100 x = ((x >> 2) & 0x33333333) + (x & 0x33333333); 136 x = ((x >> 2) & 0x33333333) + (x & 0x33333333);
101 x = ((x >> 4) + x) & 0x0f0f0f0f; 137 x = ((x >> 4) + x) & 0x0f0f0f0f;
102 x *= 0x01010101; 138 x *= 0x01010101;
103 139
104 return x >> 24; 140 return x >> 24;
105} 141}
106#endif 142#endif
107 143
108#endif 144#if ECB_GCC_VERSION(4,3)
145# define ecb_bswap32(x) __builtin_bswap32 (x)
146# define ecb_bswap16(x) (__builtin_bswap32(x) >> 16)
147#else
148ECB_HEADER_INLINE uint32_t ecb_bswap32 (uint32_t x) ecb_const;
149ECB_HEADER_INLINE uint32_t
150ecb_bswap32 (uint32_t x)
151{
152 return (x >> 24)
153 | ((x >> 8) & 0x0000ff00)
154 | ((x << 8) & 0x00ff0000)
155 | (x << 24);
156}
109 157
158ECB_HEADER_INLINE uint32_t ecb_bswap16 (uint32_t x) ecb_const;
159ECB_HEADER_INLINE uint32_t
160ecb_bswap16 (uint32_t x)
161{
162 return ((x >> 8) & 0xff)
163 | ((x << 8) & 0x00ff0000)
164 | (x << 24);
165}
166#endif
167
168#if ECB_GCC_VERSION(4,5)
169# define ecb_unreachable() __builtin_unreachable ()
170#else
171/* this seems to work fine, but gcc always emits a warning for it :/ */
172ECB_HEADER_INLINE void ecb_unreachable (void) ecb_noreturn;
173ECB_HEADER_INLINE void ecb_unreachable (void) { }
174#endif
175
176ECB_HEADER_INLINE unsigned char ecb_byteorder_helper (void) ecb_const;
177ECB_HEADER_INLINE unsigned char
178ecb_byteorder_helper (void)
179{
180 const uint32_t u = 0x11223344;
181 return *(unsigned char *)&u;
182}
183
184ECB_HEADER_INLINE ecb_bool ecb_big_endian (void) ecb_const;
185ECB_HEADER_INLINE ecb_bool ecb_big_endian (void) { return ecb_byteorder_helper () == 0x11; };
186ECB_HEADER_INLINE ecb_bool ecb_little_endian (void) ecb_const;
187ECB_HEADER_INLINE ecb_bool ecb_little_endian (void) { return ecb_byteorder_helper () == 0x44; };
188
189#if ECB_GCC_VERSION(3,0)
190# define ecb_mod(m,n) ((m) % (n) + ((m) % (n) < 0 ? (n) : 0))
191#else
192# define ecb_mod(m,n) ((m) < 0 ? ((n) - 1 - ((-1 - (m)) % (n))) : ((m) % (n)))
193#endif
194
195#if ecb_cplusplus_does_not_suck
196// does not work for local types (http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2008/n2657.htm)
197template<typename T, int N>
198static inline int ecb_array_length (const T (&arr)[N])
199{
200 return N;
201}
202#else
203#define ecb_array_length(name) (sizeof (name) / sizeof (name [0]))
204#endif
205
206ECB_INLINE uint32_t ecb_rotr32 (uint32_t x, unsigned int count) ecb_const;
207ECB_INLINE uint32_t
208ecb_rotr32 (uint32_t x, unsigned int count)
209{
210 return (x << (32 - count)) | (x >> count);
211}
212
213ECB_INLINE uint32_t ecb_rotl32 (uint32_t x, unsigned int count) ecb_const;
214ECB_INLINE uint32_t
215ecb_rotl32 (uint32_t x, unsigned int count)
216{
217 return (x >> (32 - count)) | (x << count);
218}
219
220#endif
221

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