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Comparing libecb/ecb.h (file contents):
Revision 1.4 by root, Thu May 26 17:26:03 2011 UTC vs.
Revision 1.50 by root, Fri Jun 17 21:16:11 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#ifdef _WIN32
34 typedef signed char int8_t;
35 typedef unsigned char uint8_t;
36 typedef signed short int16_t;
37 typedef unsigned short uint16_t;
38 typedef signed int int32_t;
39 typedef unsigned int uint32_t;
40 #if __GNUC__
41 typedef signed long long int64_t;
42 typedef unsigned long long uint64_t;
43 #else
44 typedef signed __int64 int64_t;
45 typedef unsigned __int64 uint64_t;
46 #endif
47#else
48 #include <inttypes.h>
49#endif
50
51/* many compilers define _GNUC_ to some versions but then only implement
52 * what their idiot authors think are the "more important" extensions,
53 * causing enourmous grief in return for some better fake benchmark numbers.
54 * or so.
55 * we try to detect these and simply assume they are not gcc - if they have
56 * an issue with that they should have done it right in the first place.
57 */
58#ifndef ECB_GCC_VERSION
59 #if !defined(__GNUC_MINOR__) || defined(__INTEL_COMPILER) || defined(__SUNPRO_C) || defined(__SUNPRO_CC) || defined(__llvm__) || defined(__clang__)
60 #define ECB_GCC_VERSION(major,minor) 0
61 #else
32#define ECB_GCC_VERSION(major,minor) (__GNUC__ > (major) || (__GNUC__ == (major) && __GNUC_MINOR__ >= (minor))) 62 #define ECB_GCC_VERSION(major,minor) (__GNUC__ > (major) || (__GNUC__ == (major) && __GNUC_MINOR__ >= (minor)))
63 #endif
64#endif
33 65
66#define ECB_C99 (__STDC_VERSION__ >= 199901L)
67
34#ifndef __cplusplus 68#if __cplusplus
35# if __STDC_VERSION__ >= 199901L 69 #define ecb_inline static inline
36# define ECB_INLINE inline 70#elif ECB_GCC_VERSION(2,5)
37typedef _Bool ecb_bool; 71 #define ecb_inline static __inline__
72#elif ECB_C99
73 #define ecb_inline static inline
38# else 74#else
39# define ECB_INLINE inline /* yeah! */ 75 #define ecb_inline static
76#endif
77
78#if ECB_GCC_VERSION(3,3)
79 #define ecb_restrict __restrict__
80#elif ECB_C99
81 #define ecb_restrict restrict
82#else
83 #define ecb_restrict
84#endif
85
40typedef int ecb_bool; 86typedef int ecb_bool;
41# endif
42#endif
43 87
44#define ECB_HEADER_INLINE static ECB_INLINE 88#define ECB_CONCAT_(a, b) a ## b
89#define ECB_CONCAT(a, b) ECB_CONCAT_(a, b)
90#define ECB_STRINGIFY_(a) # a
91#define ECB_STRINGIFY(a) ECB_STRINGIFY_(a)
92
93#define ecb_function_ ecb_inline
45 94
46#if ECB_GCC_VERSION(3,1) 95#if ECB_GCC_VERSION(3,1)
47# define ecb_attribute(attrlist) __attribute__(attrlist) 96 #define ecb_attribute(attrlist) __attribute__(attrlist)
48# define ecb_is_constant(c) __builtin_constant_p (c) 97 #define ecb_is_constant(expr) __builtin_constant_p (expr)
49# define ecb_expect(expr,value) __builtin_expect ((expr),(value)) 98 #define ecb_expect(expr,value) __builtin_expect ((expr),(value))
50# define ecb_prefetch(addr,rw,locality) __builtin_prefetch (addr, rw, locality) 99 #define ecb_prefetch(addr,rw,locality) __builtin_prefetch (addr, rw, locality)
51#else 100#else
52# define ecb_attribute(attrlist) 101 #define ecb_attribute(attrlist)
53# define ecb_is_constant(c) 0 102 #define ecb_is_constant(expr) 0
54# define ecb_expect(expr,value) (expr) 103 #define ecb_expect(expr,value) (expr)
55# define ecb_prefetch(addr,rw,locality) 104 #define ecb_prefetch(addr,rw,locality)
56#endif 105#endif
57 106
58/* no emulation for ecb_decltype */ 107/* no emulation for ecb_decltype */
59#if ECB_GCC_VERSION(4,5) 108#if ECB_GCC_VERSION(4,5)
60# define ecb_decltype(x) __decltype(x) 109 #define ecb_decltype(x) __decltype(x)
61#elif ECB_GCC_VERSION(3,0) 110#elif ECB_GCC_VERSION(3,0)
62# define ecb_decltype(x) typeof(x) 111 #define ecb_decltype(x) __typeof(x)
63#endif 112#endif
64 113
65#define ecb_noinline ecb_attribute ((noinline)) 114#define ecb_noinline ecb_attribute ((__noinline__))
66#define ecb_noreturn ecb_attribute ((noreturn)) 115#define ecb_noreturn ecb_attribute ((__noreturn__))
67#define ecb_unused ecb_attribute ((unused)) 116#define ecb_unused ecb_attribute ((__unused__))
68#define ecb_const ecb_attribute ((const)) 117#define ecb_const ecb_attribute ((__const__))
69#define ecb_pure ecb_attribute ((pure)) 118#define ecb_pure ecb_attribute ((__pure__))
70#define ecb_hot ecb_attribute ((hot)) /* 4.3 */
71#define ecb_cold ecb_attribute ((cold)) /* 4.3 */
72 119
73#if ECB_GCC_VERSION(4,5) 120#if ECB_GCC_VERSION(4,3)
74# define ecb_unreachable() __builtin_unreachable () 121 #define ecb_artificial ecb_attribute ((__artificial__))
122 #define ecb_hot ecb_attribute ((__hot__))
123 #define ecb_cold ecb_attribute ((__cold__))
75#else 124#else
76/* this seems to work fine, but gcc always emits a warning for it :/ */ 125 #define ecb_artificial
77ECB_HEADER_INLINE void ecb_unreachable () ecb_attribute ((noreturn)); 126 #define ecb_hot
78ECB_HEADER_INLINE void ecb_unreachable () { } 127 #define ecb_cold
79#endif 128#endif
80 129
81/* put into ifs if you are very sure that the expression */ 130/* put around conditional expressions if you are very sure that the */
82/* is mostly true or mosty false. note that these return */ 131/* expression is mostly true or mostly false. note that these return */
83/* booleans, not the expression. */ 132/* booleans, not the expression. */
84#define ecb_expect_false(expr) ecb_expect ((expr) ? 1 : 0, 0) 133#define ecb_expect_false(expr) ecb_expect (!!(expr), 0)
85#define ecb_expect_true(expr) ecb_expect ((expr) ? 1 : 0, 1) 134#define ecb_expect_true(expr) ecb_expect (!!(expr), 1)
86 135/* for compatibility to the rest of the world */
87/* try to tell the compiler that some condition is definitely true */ 136#define ecb_likely(expr) ecb_expect_true (expr)
88#define ecb_assume(cond) do { if (!(cond)) unreachable (); } while (0) 137#define ecb_unlikely(expr) ecb_expect_false (expr)
89 138
90/* count trailing zero bits and count # of one bits */ 139/* count trailing zero bits and count # of one bits */
91#if ECB_GCC_VERSION(3,4) 140#if ECB_GCC_VERSION(3,4)
92ECB_HEADER_INLINE int ecb_ctz32 (unsigned int x) { return __builtin_ctz (x); } 141 /* we assume int == 32 bit, long == 32 or 64 bit and long long == 64 bit */
93ECB_HEADER_INLINE int ecb_popcount32 (unsigned int x) { return __builtin_popcount (x); } 142 #define ecb_ld32(x) (__builtin_clz (x) ^ 31)
143 #define ecb_ld64(x) (__builtin_clzll (x) ^ 63)
144 #define ecb_ctz32(x) __builtin_ctz (x)
145 #define ecb_ctz64(x) __builtin_ctzll (x)
146 #define ecb_popcount32(x) __builtin_popcount (x)
147 /* no popcountll */
94#else 148#else
95ECB_HEADER_INLINE 149 ecb_function_ int ecb_ctz32 (uint32_t x) ecb_const;
96ecb_ctz32 (unsigned int x) ecb_const 150 ecb_function_ int
151 ecb_ctz32 (uint32_t x)
152 {
153 int r = 0;
154
155 x &= ~x + 1; /* this isolates the lowest bit */
156
157#if ECB_branchless_on_i386
158 r += !!(x & 0xaaaaaaaa) << 0;
159 r += !!(x & 0xcccccccc) << 1;
160 r += !!(x & 0xf0f0f0f0) << 2;
161 r += !!(x & 0xff00ff00) << 3;
162 r += !!(x & 0xffff0000) << 4;
163#else
164 if (x & 0xaaaaaaaa) r += 1;
165 if (x & 0xcccccccc) r += 2;
166 if (x & 0xf0f0f0f0) r += 4;
167 if (x & 0xff00ff00) r += 8;
168 if (x & 0xffff0000) r += 16;
169#endif
170
171 return r;
172 }
173
174 ecb_function_ int ecb_ctz64 (uint64_t x) ecb_const;
175 ecb_function_ int
176 ecb_ctz64 (uint64_t x)
177 {
178 int shift = x & 0xffffffffU ? 0 : 32;
179 return ecb_ctz32 (x >> shift) + shift;
180 }
181
182 ecb_function_ int ecb_popcount32 (uint32_t x) ecb_const;
183 ecb_function_ int
184 ecb_popcount32 (uint32_t x)
185 {
186 x -= (x >> 1) & 0x55555555;
187 x = ((x >> 2) & 0x33333333) + (x & 0x33333333);
188 x = ((x >> 4) + x) & 0x0f0f0f0f;
189 x *= 0x01010101;
190
191 return x >> 24;
192 }
193
194 /* you have the choice beetween something with a table lookup, */
195 /* something using lots of bit arithmetic and a simple loop */
196 /* we went for the loop */
197 ecb_function_ int ecb_ld32 (uint32_t x) ecb_const;
198 ecb_function_ int ecb_ld32 (uint32_t x)
199 {
200 int r = 0;
201
202 if (x >> 16) { x >>= 16; r += 16; }
203 if (x >> 8) { x >>= 8; r += 8; }
204 if (x >> 4) { x >>= 4; r += 4; }
205 if (x >> 2) { x >>= 2; r += 2; }
206 if (x >> 1) { r += 1; }
207
208 return r;
209 }
210
211 ecb_function_ int ecb_ld64 (uint64_t x) ecb_const;
212 ecb_function_ int ecb_ld64 (uint64_t x)
213 {
214 int r = 0;
215
216 if (x >> 32) { x >>= 32; r += 32; }
217
218 return r + ecb_ld32 (x);
219 }
220#endif
221
222/* popcount64 is only available on 64 bit cpus as gcc builtin */
223/* so for this version we are lazy */
224ecb_function_ int ecb_popcount64 (uint64_t x) ecb_const;
225ecb_function_ int
226ecb_popcount64 (uint64_t x)
97{ 227{
98 int r = 0; 228 return ecb_popcount32 (x) + ecb_popcount32 (x >> 32);
99
100 x &= -x; /* this isolates the lowest bit */
101
102 if (x & 0xaaaaaaaa) r += 1;
103 if (x & 0xcccccccc) r += 2;
104 if (x & 0xf0f0f0f0) r += 4;
105 if (x & 0xff00ff00) r += 8;
106 if (x & 0xffff0000) r += 16;
107
108 return r;
109} 229}
110 230
111ECB_HEADER_INLINE 231ecb_inline uint8_t ecb_rotl8 (uint8_t x, unsigned int count) ecb_const;
112ecb_popcount32 (unsigned int x) ecb_const 232ecb_inline uint8_t ecb_rotr8 (uint8_t x, unsigned int count) ecb_const;
113{ 233ecb_inline uint16_t ecb_rotl16 (uint16_t x, unsigned int count) ecb_const;
114 x -= (x >> 1) & 0x55555555; 234ecb_inline uint16_t ecb_rotr16 (uint16_t x, unsigned int count) ecb_const;
115 x = ((x >> 2) & 0x33333333) + (x & 0x33333333); 235ecb_inline uint32_t ecb_rotl32 (uint32_t x, unsigned int count) ecb_const;
116 x = ((x >> 4) + x) & 0x0f0f0f0f; 236ecb_inline uint32_t ecb_rotr32 (uint32_t x, unsigned int count) ecb_const;
117 x *= 0x01010101; 237ecb_inline uint64_t ecb_rotl64 (uint64_t x, unsigned int count) ecb_const;
238ecb_inline uint64_t ecb_rotr64 (uint64_t x, unsigned int count) ecb_const;
118 239
119 return x >> 24; 240ecb_inline uint8_t ecb_rotl8 (uint8_t x, unsigned int count) { return (x >> ( 8 - count)) | (x << count); }
120} 241ecb_inline uint8_t ecb_rotr8 (uint8_t x, unsigned int count) { return (x << ( 8 - count)) | (x >> count); }
121#endif 242ecb_inline uint16_t ecb_rotl16 (uint16_t x, unsigned int count) { return (x >> (16 - count)) | (x << count); }
243ecb_inline uint16_t ecb_rotr16 (uint16_t x, unsigned int count) { return (x << (16 - count)) | (x >> count); }
244ecb_inline uint32_t ecb_rotl32 (uint32_t x, unsigned int count) { return (x >> (32 - count)) | (x << count); }
245ecb_inline uint32_t ecb_rotr32 (uint32_t x, unsigned int count) { return (x << (32 - count)) | (x >> count); }
246ecb_inline uint64_t ecb_rotl64 (uint64_t x, unsigned int count) { return (x >> (64 - count)) | (x << count); }
247ecb_inline uint64_t ecb_rotr64 (uint64_t x, unsigned int count) { return (x << (64 - count)) | (x >> count); }
122 248
123ECB_HEADER_INLINE unsigned char 249#if ECB_GCC_VERSION(4,3)
250 #define ecb_bswap16(x) (__builtin_bswap32 (x) >> 16)
251 #define ecb_bswap32(x) __builtin_bswap32 (x)
252 #define ecb_bswap64(x) __builtin_bswap64 (x)
253#else
254 ecb_function_ uint16_t ecb_bswap16 (uint16_t x) ecb_const;
255 ecb_function_ uint16_t
256 ecb_bswap16 (uint16_t x)
257 {
258 return ecb_rotl16 (x, 8);
259 }
260
261 ecb_function_ uint32_t ecb_bswap32 (uint32_t x) ecb_const;
262 ecb_function_ uint32_t
263 ecb_bswap32 (uint32_t x)
264 {
265 return (((uint32_t)ecb_bswap16 (x)) << 16) | ecb_bswap16 (x >> 16);
266 }
267
268 ecb_function_ uint64_t ecb_bswap64 (uint64_t x) ecb_const;
269 ecb_function_ uint64_t
270 ecb_bswap64 (uint64_t x)
271 {
272 return (((uint64_t)ecb_bswap32 (x)) << 32) | ecb_bswap32 (x >> 32);
273 }
274#endif
275
276#if ECB_GCC_VERSION(4,5)
277 #define ecb_unreachable() __builtin_unreachable ()
278#else
279 /* this seems to work fine, but gcc always emits a warning for it :/ */
280 ecb_function_ void ecb_unreachable (void) ecb_noreturn;
281 ecb_function_ void ecb_unreachable (void) { }
282#endif
283
284/* try to tell the compiler that some condition is definitely true */
285#define ecb_assume(cond) do { if (!(cond)) ecb_unreachable (); } while (0)
286
287ecb_function_ unsigned char ecb_byteorder_helper (void) ecb_const;
288ecb_function_ unsigned char
124ecb_byteorder_helper () ecb_const 289ecb_byteorder_helper (void)
125{ 290{
126 const uint32_t u = 0x11223344; 291 const uint32_t u = 0x11223344;
127 return *(unsigned char *)&u; 292 return *(unsigned char *)&u;
128} 293}
129 294
295ecb_function_ ecb_bool ecb_big_endian (void) ecb_const;
130ECB_HEADER_INLINE ecb_bool ecb_big_endian () ecb_const { return ecb_byteorder_helper () == 0x11; }; 296ecb_function_ ecb_bool ecb_big_endian (void) { return ecb_byteorder_helper () == 0x11; }
297ecb_function_ ecb_bool ecb_little_endian (void) ecb_const;
131ECB_HEADER_INLINE ecb_bool ecb_little_endian () ecb_const { return ecb_byteorder_helper () == 0x44; }; 298ecb_function_ ecb_bool ecb_little_endian (void) { return ecb_byteorder_helper () == 0x44; }
132 299
300#if ECB_GCC_VERSION(3,0) || ECB_C99
301 #define ecb_mod(m,n) ((m) % (n) + ((m) % (n) < 0 ? (n) : 0))
302#else
303 #define ecb_mod(m,n) ((m) < 0 ? ((n) - 1 - ((-1 - (m)) % (n))) : ((m) % (n)))
133#endif 304#endif
134 305
306#if ecb_cplusplus_does_not_suck
307 /* does not work for local types (http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2008/n2657.htm) */
308 template<typename T, int N>
309 static inline int ecb_array_length (const T (&arr)[N])
310 {
311 return N;
312 }
313#else
314 #define ecb_array_length(name) (sizeof (name) / sizeof (name [0]))
315#endif
316
317#endif
318

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