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Revision: 1.90
Committed: Tue May 29 14:09:49 2012 UTC (12 years ago) by root
Content type: text/plain
Branch: MAIN
Changes since 1.89: +20 -3 lines
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# User Rev Content
1 root 1.1 /*
2 root 1.17 * libecb - http://software.schmorp.de/pkg/libecb
3 root 1.1 *
4 root 1.72 * Copyright (©) 2009-2012 Marc Alexander Lehmann <libecb@schmorp.de>
5 root 1.7 * Copyright (©) 2011 Emanuele Giaquinta
6 root 1.1 * All rights reserved.
7     *
8     * Redistribution and use in source and binary forms, with or without modifica-
9     * tion, are permitted provided that the following conditions are met:
10     *
11     * 1. Redistributions of source code must retain the above copyright notice,
12     * this list of conditions and the following disclaimer.
13     *
14     * 2. Redistributions in binary form must reproduce the above copyright
15     * notice, this list of conditions and the following disclaimer in the
16     * documentation and/or other materials provided with the distribution.
17     *
18     * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
19     * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MER-
20     * CHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO
21     * EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPE-
22     * CIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
23     * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
24     * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
25     * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTH-
26     * ERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
27     * OF THE POSSIBILITY OF SUCH DAMAGE.
28     */
29    
30     #ifndef ECB_H
31     #define ECB_H
32    
33 root 1.87 /* 16 bits major, 16 bits minor */
34     #define ECB_VERSION 0x00010001
35    
36 root 1.44 #ifdef _WIN32
37     typedef signed char int8_t;
38     typedef unsigned char uint8_t;
39     typedef signed short int16_t;
40     typedef unsigned short uint16_t;
41     typedef signed int int32_t;
42     typedef unsigned int uint32_t;
43     #if __GNUC__
44     typedef signed long long int64_t;
45     typedef unsigned long long uint64_t;
46 root 1.51 #else /* _MSC_VER || __BORLANDC__ */
47 root 1.44 typedef signed __int64 int64_t;
48     typedef unsigned __int64 uint64_t;
49     #endif
50 root 1.87 #ifdef _WIN64
51     #define ECB_PTRSIZE 8
52     typedef uint64_t uintptr_t;
53     typedef int64_t intptr_t;
54     #else
55     #define ECB_PTRSIZE 4
56     typedef uint32_t uintptr_t;
57     typedef int32_t intptr_t;
58     #endif
59 root 1.89 typedef intptr_t ptrdiff_t;
60 root 1.44 #else
61     #include <inttypes.h>
62 root 1.87 #if UINTMAX_MAX > 0xffffffffU
63     #define ECB_PTRSIZE 8
64     #else
65     #define ECB_PTRSIZE 4
66     #endif
67 root 1.44 #endif
68 root 1.6
69 root 1.12 /* many compilers define _GNUC_ to some versions but then only implement
70     * what their idiot authors think are the "more important" extensions,
71 sf-exg 1.59 * causing enormous grief in return for some better fake benchmark numbers.
72 root 1.18 * or so.
73 root 1.12 * we try to detect these and simply assume they are not gcc - if they have
74     * an issue with that they should have done it right in the first place.
75     */
76 root 1.14 #ifndef ECB_GCC_VERSION
77 root 1.85 #if !defined __GNUC_MINOR__ || defined __INTEL_COMPILER || defined __SUNPRO_C || defined __SUNPRO_CC || defined __llvm__ || defined __clang__
78 root 1.37 #define ECB_GCC_VERSION(major,minor) 0
79     #else
80     #define ECB_GCC_VERSION(major,minor) (__GNUC__ > (major) || (__GNUC__ == (major) && __GNUC_MINOR__ >= (minor)))
81     #endif
82 root 1.12 #endif
83 root 1.1
84 root 1.90 #define ECB_C99 (__STDC_VERSION__ >= 199901L)
85     #define ECB_C11 (__STDC_VERSION__ >= 201112L)
86    
87 root 1.52 /*****************************************************************************/
88    
89 root 1.58 /* ECB_NO_THREADS - ecb is not used by multiple threads, ever */
90     /* ECB_NO_SMP - ecb might be used in multiple threads, but only on a single cpu */
91    
92 root 1.79 #if ECB_NO_THREADS
93     # define ECB_NO_SMP 1
94     #endif
95    
96 root 1.58 #if ECB_NO_THREADS || ECB_NO_SMP
97 root 1.64 #define ECB_MEMORY_FENCE do { } while (0)
98 root 1.58 #endif
99    
100 root 1.52 #ifndef ECB_MEMORY_FENCE
101 root 1.90 #if ECB_C11 && !defined __STDC_NO_ATOMICS__
102     /* we assume that these memory fences work on all variables/all memory accesses, */
103     /* not just C11 atomics and atomic accesses */
104     #include <stdatomic.h>
105     #define ECB_MEMORY_FENCE atomic_thread_fence (memory_order_acq_rel)
106     #define ECB_MEMORY_FENCE_ACQUIRE atomic_thread_fence (memory_order_acquire)
107     #define ECB_MEMORY_FENCE_RELEASE atomic_thread_fence (memory_order_release)
108     #endif
109     #endif
110    
111     #ifndef ECB_MEMORY_FENCE
112 root 1.85 #if ECB_GCC_VERSION(2,5) || defined __INTEL_COMPILER || (__llvm__ && __GNUC__) || __SUNPRO_C >= 0x5110 || __SUNPRO_CC >= 0x5110
113 root 1.73 #if __i386 || __i386__
114 root 1.54 #define ECB_MEMORY_FENCE __asm__ __volatile__ ("lock; orb $0, -1(%%esp)" : : : "memory")
115 root 1.57 #define ECB_MEMORY_FENCE_ACQUIRE ECB_MEMORY_FENCE /* non-lock xchg might be enough */
116     #define ECB_MEMORY_FENCE_RELEASE do { } while (0) /* unlikely to change in future cpus */
117 root 1.73 #elif __amd64 || __amd64__ || __x86_64 || __x86_64__
118 root 1.52 #define ECB_MEMORY_FENCE __asm__ __volatile__ ("mfence" : : : "memory")
119     #define ECB_MEMORY_FENCE_ACQUIRE __asm__ __volatile__ ("lfence" : : : "memory")
120 root 1.57 #define ECB_MEMORY_FENCE_RELEASE __asm__ __volatile__ ("sfence") /* play safe - not needed in any current cpu */
121 root 1.63 #elif __powerpc__ || __ppc__ || __powerpc64__ || __ppc64__
122     #define ECB_MEMORY_FENCE __asm__ __volatile__ ("sync" : : : "memory")
123 root 1.85 #elif defined __ARM_ARCH_6__ || defined __ARM_ARCH_6J__ \
124     || defined __ARM_ARCH_6K__ || defined __ARM_ARCH_6ZK__
125 root 1.84 #define ECB_MEMORY_FENCE __asm__ __volatile__ ("mcr p15,0,%0,c7,c10,5" : : "r" (0) : "memory")
126 root 1.85 #elif defined __ARM_ARCH_7__ || defined __ARM_ARCH_7A__ \
127     || defined __ARM_ARCH_7M__ || defined __ARM_ARCH_7R__
128 root 1.65 #define ECB_MEMORY_FENCE __asm__ __volatile__ ("dmb" : : : "memory")
129 root 1.73 #elif __sparc || __sparc__
130 root 1.74 #define ECB_MEMORY_FENCE __asm__ __volatile__ ("membar #LoadStore | #LoadLoad | #StoreStore | #StoreLoad | " : : : "memory")
131 root 1.77 #define ECB_MEMORY_FENCE_ACQUIRE __asm__ __volatile__ ("membar #LoadStore | #LoadLoad" : : : "memory")
132 root 1.74 #define ECB_MEMORY_FENCE_RELEASE __asm__ __volatile__ ("membar #LoadStore | #StoreStore")
133 root 1.85 #elif defined __s390__ || defined __s390x__
134 root 1.77 #define ECB_MEMORY_FENCE __asm__ __volatile__ ("bcr 15,0" : : : "memory")
135 root 1.85 #elif defined __mips__
136 root 1.80 #define ECB_MEMORY_FENCE __asm__ __volatile__ ("sync" : : : "memory")
137 root 1.86 #elif defined __alpha__
138     #define ECB_MEMORY_FENCE __asm__ __volatile__ ("mb" : : : "memory")
139 root 1.52 #endif
140     #endif
141     #endif
142    
143     #ifndef ECB_MEMORY_FENCE
144 root 1.85 #if ECB_GCC_VERSION(4,4) || defined __INTEL_COMPILER || defined __clang__
145 root 1.52 #define ECB_MEMORY_FENCE __sync_synchronize ()
146 root 1.62 /*#define ECB_MEMORY_FENCE_ACQUIRE ({ char dummy = 0; __sync_lock_test_and_set (&dummy, 1); }) */
147     /*#define ECB_MEMORY_FENCE_RELEASE ({ char dummy = 1; __sync_lock_release (&dummy ); }) */
148 root 1.57 #elif _MSC_VER >= 1400 /* VC++ 2005 */
149     #pragma intrinsic(_ReadBarrier,_WriteBarrier,_ReadWriteBarrier)
150     #define ECB_MEMORY_FENCE _ReadWriteBarrier ()
151     #define ECB_MEMORY_FENCE_ACQUIRE _ReadWriteBarrier () /* according to msdn, _ReadBarrier is not a load fence */
152     #define ECB_MEMORY_FENCE_RELEASE _WriteBarrier ()
153 root 1.85 #elif defined _WIN32
154 root 1.55 #include <WinNT.h>
155 root 1.57 #define ECB_MEMORY_FENCE MemoryBarrier () /* actually just xchg on x86... scary */
156 root 1.72 #elif __SUNPRO_C >= 0x5110 || __SUNPRO_CC >= 0x5110
157     #include <mbarrier.h>
158     #define ECB_MEMORY_FENCE __machine_rw_barrier ()
159     #define ECB_MEMORY_FENCE_ACQUIRE __machine_r_barrier ()
160     #define ECB_MEMORY_FENCE_RELEASE __machine_w_barrier ()
161 root 1.82 #elif __xlC__
162 root 1.83 #define ECB_MEMORY_FENCE __sync ()
163 root 1.52 #endif
164     #endif
165    
166 root 1.53 #ifndef ECB_MEMORY_FENCE
167 root 1.62 #if !ECB_AVOID_PTHREADS
168     /*
169     * if you get undefined symbol references to pthread_mutex_lock,
170     * or failure to find pthread.h, then you should implement
171     * the ECB_MEMORY_FENCE operations for your cpu/compiler
172     * OR provide pthread.h and link against the posix thread library
173     * of your system.
174     */
175     #include <pthread.h>
176     #define ECB_NEEDS_PTHREADS 1
177     #define ECB_MEMORY_FENCE_NEEDS_PTHREADS 1
178 root 1.52
179 root 1.62 static pthread_mutex_t ecb_mf_lock = PTHREAD_MUTEX_INITIALIZER;
180     #define ECB_MEMORY_FENCE do { pthread_mutex_lock (&ecb_mf_lock); pthread_mutex_unlock (&ecb_mf_lock); } while (0)
181     #endif
182     #endif
183    
184 root 1.85 #if !defined ECB_MEMORY_FENCE_ACQUIRE && defined ECB_MEMORY_FENCE
185 root 1.52 #define ECB_MEMORY_FENCE_ACQUIRE ECB_MEMORY_FENCE
186 root 1.62 #endif
187    
188 root 1.85 #if !defined ECB_MEMORY_FENCE_RELEASE && defined ECB_MEMORY_FENCE
189 root 1.52 #define ECB_MEMORY_FENCE_RELEASE ECB_MEMORY_FENCE
190     #endif
191    
192     /*****************************************************************************/
193    
194 root 1.39 #if __cplusplus
195 root 1.46 #define ecb_inline static inline
196 root 1.38 #elif ECB_GCC_VERSION(2,5)
197 root 1.46 #define ecb_inline static __inline__
198 root 1.39 #elif ECB_C99
199 root 1.46 #define ecb_inline static inline
200 root 1.29 #else
201 root 1.46 #define ecb_inline static
202 root 1.38 #endif
203    
204     #if ECB_GCC_VERSION(3,3)
205     #define ecb_restrict __restrict__
206 root 1.39 #elif ECB_C99
207 root 1.38 #define ecb_restrict restrict
208     #else
209     #define ecb_restrict
210 root 1.4 #endif
211    
212 root 1.38 typedef int ecb_bool;
213    
214 root 1.8 #define ECB_CONCAT_(a, b) a ## b
215     #define ECB_CONCAT(a, b) ECB_CONCAT_(a, b)
216     #define ECB_STRINGIFY_(a) # a
217     #define ECB_STRINGIFY(a) ECB_STRINGIFY_(a)
218    
219 root 1.46 #define ecb_function_ ecb_inline
220 root 1.3
221 root 1.1 #if ECB_GCC_VERSION(3,1)
222 root 1.37 #define ecb_attribute(attrlist) __attribute__(attrlist)
223     #define ecb_is_constant(expr) __builtin_constant_p (expr)
224     #define ecb_expect(expr,value) __builtin_expect ((expr),(value))
225     #define ecb_prefetch(addr,rw,locality) __builtin_prefetch (addr, rw, locality)
226     #else
227     #define ecb_attribute(attrlist)
228     #define ecb_is_constant(expr) 0
229     #define ecb_expect(expr,value) (expr)
230     #define ecb_prefetch(addr,rw,locality)
231 root 1.1 #endif
232    
233 root 1.2 /* no emulation for ecb_decltype */
234 root 1.1 #if ECB_GCC_VERSION(4,5)
235 root 1.37 #define ecb_decltype(x) __decltype(x)
236 root 1.1 #elif ECB_GCC_VERSION(3,0)
237 root 1.39 #define ecb_decltype(x) __typeof(x)
238 root 1.1 #endif
239    
240 root 1.24 #define ecb_noinline ecb_attribute ((__noinline__))
241     #define ecb_unused ecb_attribute ((__unused__))
242     #define ecb_const ecb_attribute ((__const__))
243     #define ecb_pure ecb_attribute ((__pure__))
244 root 1.35
245 root 1.90 #if ECB_C11
246     #define ecb_noreturn _Noreturn
247     #else
248     #define ecb_noreturn ecb_attribute ((__noreturn__))
249     #endif
250    
251 root 1.35 #if ECB_GCC_VERSION(4,3)
252 root 1.39 #define ecb_artificial ecb_attribute ((__artificial__))
253     #define ecb_hot ecb_attribute ((__hot__))
254     #define ecb_cold ecb_attribute ((__cold__))
255 root 1.35 #else
256     #define ecb_artificial
257     #define ecb_hot
258     #define ecb_cold
259     #endif
260 root 1.1
261 root 1.39 /* put around conditional expressions if you are very sure that the */
262     /* expression is mostly true or mostly false. note that these return */
263     /* booleans, not the expression. */
264 root 1.33 #define ecb_expect_false(expr) ecb_expect (!!(expr), 0)
265     #define ecb_expect_true(expr) ecb_expect (!!(expr), 1)
266 root 1.36 /* for compatibility to the rest of the world */
267 root 1.33 #define ecb_likely(expr) ecb_expect_true (expr)
268     #define ecb_unlikely(expr) ecb_expect_false (expr)
269 root 1.1
270 root 1.3 /* count trailing zero bits and count # of one bits */
271 root 1.1 #if ECB_GCC_VERSION(3,4)
272 root 1.49 /* we assume int == 32 bit, long == 32 or 64 bit and long long == 64 bit */
273     #define ecb_ld32(x) (__builtin_clz (x) ^ 31)
274     #define ecb_ld64(x) (__builtin_clzll (x) ^ 63)
275 root 1.35 #define ecb_ctz32(x) __builtin_ctz (x)
276 root 1.49 #define ecb_ctz64(x) __builtin_ctzll (x)
277 root 1.35 #define ecb_popcount32(x) __builtin_popcount (x)
278 root 1.49 /* no popcountll */
279 root 1.1 #else
280 root 1.39 ecb_function_ int ecb_ctz32 (uint32_t x) ecb_const;
281     ecb_function_ int
282 root 1.35 ecb_ctz32 (uint32_t x)
283     {
284     int r = 0;
285    
286 root 1.48 x &= ~x + 1; /* this isolates the lowest bit */
287 root 1.35
288 root 1.50 #if ECB_branchless_on_i386
289     r += !!(x & 0xaaaaaaaa) << 0;
290     r += !!(x & 0xcccccccc) << 1;
291     r += !!(x & 0xf0f0f0f0) << 2;
292     r += !!(x & 0xff00ff00) << 3;
293     r += !!(x & 0xffff0000) << 4;
294     #else
295 root 1.35 if (x & 0xaaaaaaaa) r += 1;
296     if (x & 0xcccccccc) r += 2;
297     if (x & 0xf0f0f0f0) r += 4;
298     if (x & 0xff00ff00) r += 8;
299     if (x & 0xffff0000) r += 16;
300 root 1.50 #endif
301 root 1.35
302     return r;
303     }
304    
305 root 1.49 ecb_function_ int ecb_ctz64 (uint64_t x) ecb_const;
306     ecb_function_ int
307     ecb_ctz64 (uint64_t x)
308     {
309     int shift = x & 0xffffffffU ? 0 : 32;
310 root 1.50 return ecb_ctz32 (x >> shift) + shift;
311 root 1.49 }
312    
313 root 1.39 ecb_function_ int ecb_popcount32 (uint32_t x) ecb_const;
314     ecb_function_ int
315 root 1.35 ecb_popcount32 (uint32_t x)
316     {
317     x -= (x >> 1) & 0x55555555;
318     x = ((x >> 2) & 0x33333333) + (x & 0x33333333);
319     x = ((x >> 4) + x) & 0x0f0f0f0f;
320     x *= 0x01010101;
321 root 1.1
322 root 1.35 return x >> 24;
323     }
324 root 1.49
325     ecb_function_ int ecb_ld32 (uint32_t x) ecb_const;
326     ecb_function_ int ecb_ld32 (uint32_t x)
327     {
328 root 1.50 int r = 0;
329 root 1.49
330 root 1.50 if (x >> 16) { x >>= 16; r += 16; }
331     if (x >> 8) { x >>= 8; r += 8; }
332     if (x >> 4) { x >>= 4; r += 4; }
333     if (x >> 2) { x >>= 2; r += 2; }
334     if (x >> 1) { r += 1; }
335 root 1.49
336     return r;
337     }
338    
339     ecb_function_ int ecb_ld64 (uint64_t x) ecb_const;
340     ecb_function_ int ecb_ld64 (uint64_t x)
341     {
342 root 1.50 int r = 0;
343 root 1.49
344 root 1.50 if (x >> 32) { x >>= 32; r += 32; }
345 root 1.49
346 root 1.50 return r + ecb_ld32 (x);
347 root 1.49 }
348 root 1.1 #endif
349    
350 root 1.88 ecb_function_ ecb_bool ecb_is_pot32 (uint32_t x) ecb_const;
351     ecb_function_ ecb_bool ecb_is_pot32 (uint32_t x) { return !(x & (x - 1)); }
352     ecb_function_ ecb_bool ecb_is_pot64 (uint64_t x) ecb_const;
353     ecb_function_ ecb_bool ecb_is_pot64 (uint64_t x) { return !(x & (x - 1)); }
354    
355 root 1.71 ecb_function_ uint8_t ecb_bitrev8 (uint8_t x) ecb_const;
356 root 1.70 ecb_function_ uint8_t ecb_bitrev8 (uint8_t x)
357     {
358     return ( (x * 0x0802U & 0x22110U)
359     | (x * 0x8020U & 0x88440U)) * 0x10101U >> 16;
360     }
361    
362 root 1.71 ecb_function_ uint16_t ecb_bitrev16 (uint16_t x) ecb_const;
363 root 1.70 ecb_function_ uint16_t ecb_bitrev16 (uint16_t x)
364     {
365     x = ((x >> 1) & 0x5555) | ((x & 0x5555) << 1);
366     x = ((x >> 2) & 0x3333) | ((x & 0x3333) << 2);
367     x = ((x >> 4) & 0x0f0f) | ((x & 0x0f0f) << 4);
368     x = ( x >> 8 ) | ( x << 8);
369    
370     return x;
371     }
372    
373 root 1.71 ecb_function_ uint32_t ecb_bitrev32 (uint32_t x) ecb_const;
374 root 1.70 ecb_function_ uint32_t ecb_bitrev32 (uint32_t x)
375     {
376     x = ((x >> 1) & 0x55555555) | ((x & 0x55555555) << 1);
377     x = ((x >> 2) & 0x33333333) | ((x & 0x33333333) << 2);
378     x = ((x >> 4) & 0x0f0f0f0f) | ((x & 0x0f0f0f0f) << 4);
379     x = ((x >> 8) & 0x00ff00ff) | ((x & 0x00ff00ff) << 8);
380     x = ( x >> 16 ) | ( x << 16);
381    
382     return x;
383     }
384    
385 root 1.49 /* popcount64 is only available on 64 bit cpus as gcc builtin */
386     /* so for this version we are lazy */
387     ecb_function_ int ecb_popcount64 (uint64_t x) ecb_const;
388     ecb_function_ int
389     ecb_popcount64 (uint64_t x)
390     {
391     return ecb_popcount32 (x) + ecb_popcount32 (x >> 32);
392     }
393    
394 root 1.50 ecb_inline uint8_t ecb_rotl8 (uint8_t x, unsigned int count) ecb_const;
395     ecb_inline uint8_t ecb_rotr8 (uint8_t x, unsigned int count) ecb_const;
396     ecb_inline uint16_t ecb_rotl16 (uint16_t x, unsigned int count) ecb_const;
397     ecb_inline uint16_t ecb_rotr16 (uint16_t x, unsigned int count) ecb_const;
398     ecb_inline uint32_t ecb_rotl32 (uint32_t x, unsigned int count) ecb_const;
399     ecb_inline uint32_t ecb_rotr32 (uint32_t x, unsigned int count) ecb_const;
400     ecb_inline uint64_t ecb_rotl64 (uint64_t x, unsigned int count) ecb_const;
401     ecb_inline uint64_t ecb_rotr64 (uint64_t x, unsigned int count) ecb_const;
402    
403     ecb_inline uint8_t ecb_rotl8 (uint8_t x, unsigned int count) { return (x >> ( 8 - count)) | (x << count); }
404     ecb_inline uint8_t ecb_rotr8 (uint8_t x, unsigned int count) { return (x << ( 8 - count)) | (x >> count); }
405     ecb_inline uint16_t ecb_rotl16 (uint16_t x, unsigned int count) { return (x >> (16 - count)) | (x << count); }
406     ecb_inline uint16_t ecb_rotr16 (uint16_t x, unsigned int count) { return (x << (16 - count)) | (x >> count); }
407     ecb_inline uint32_t ecb_rotl32 (uint32_t x, unsigned int count) { return (x >> (32 - count)) | (x << count); }
408     ecb_inline uint32_t ecb_rotr32 (uint32_t x, unsigned int count) { return (x << (32 - count)) | (x >> count); }
409     ecb_inline uint64_t ecb_rotl64 (uint64_t x, unsigned int count) { return (x >> (64 - count)) | (x << count); }
410     ecb_inline uint64_t ecb_rotr64 (uint64_t x, unsigned int count) { return (x << (64 - count)) | (x >> count); }
411    
412 root 1.13 #if ECB_GCC_VERSION(4,3)
413 root 1.49 #define ecb_bswap16(x) (__builtin_bswap32 (x) >> 16)
414     #define ecb_bswap32(x) __builtin_bswap32 (x)
415     #define ecb_bswap64(x) __builtin_bswap64 (x)
416 root 1.13 #else
417 root 1.50 ecb_function_ uint16_t ecb_bswap16 (uint16_t x) ecb_const;
418     ecb_function_ uint16_t
419     ecb_bswap16 (uint16_t x)
420 root 1.49 {
421 root 1.50 return ecb_rotl16 (x, 8);
422 root 1.49 }
423    
424 root 1.39 ecb_function_ uint32_t ecb_bswap32 (uint32_t x) ecb_const;
425     ecb_function_ uint32_t
426 root 1.35 ecb_bswap32 (uint32_t x)
427     {
428 root 1.50 return (((uint32_t)ecb_bswap16 (x)) << 16) | ecb_bswap16 (x >> 16);
429 root 1.35 }
430    
431 root 1.49 ecb_function_ uint64_t ecb_bswap64 (uint64_t x) ecb_const;
432     ecb_function_ uint64_t
433     ecb_bswap64 (uint64_t x)
434 root 1.35 {
435 root 1.50 return (((uint64_t)ecb_bswap32 (x)) << 32) | ecb_bswap32 (x >> 32);
436 root 1.35 }
437 root 1.13 #endif
438    
439     #if ECB_GCC_VERSION(4,5)
440 root 1.35 #define ecb_unreachable() __builtin_unreachable ()
441 root 1.13 #else
442 root 1.35 /* this seems to work fine, but gcc always emits a warning for it :/ */
443 root 1.75 ecb_inline void ecb_unreachable (void) ecb_noreturn;
444     ecb_inline void ecb_unreachable (void) { }
445 root 1.13 #endif
446    
447 root 1.41 /* try to tell the compiler that some condition is definitely true */
448     #define ecb_assume(cond) do { if (!(cond)) ecb_unreachable (); } while (0)
449    
450 root 1.76 ecb_inline unsigned char ecb_byteorder_helper (void) ecb_const;
451     ecb_inline unsigned char
452 root 1.23 ecb_byteorder_helper (void)
453 root 1.3 {
454     const uint32_t u = 0x11223344;
455     return *(unsigned char *)&u;
456     }
457    
458 root 1.76 ecb_inline ecb_bool ecb_big_endian (void) ecb_const;
459     ecb_inline ecb_bool ecb_big_endian (void) { return ecb_byteorder_helper () == 0x11; }
460     ecb_inline ecb_bool ecb_little_endian (void) ecb_const;
461     ecb_inline ecb_bool ecb_little_endian (void) { return ecb_byteorder_helper () == 0x44; }
462 root 1.3
463 root 1.39 #if ECB_GCC_VERSION(3,0) || ECB_C99
464 root 1.35 #define ecb_mod(m,n) ((m) % (n) + ((m) % (n) < 0 ? (n) : 0))
465 root 1.31 #else
466 root 1.35 #define ecb_mod(m,n) ((m) < 0 ? ((n) - 1 - ((-1 - (m)) % (n))) : ((m) % (n)))
467 root 1.31 #endif
468 root 1.21
469 sf-exg 1.68 #if __cplusplus
470     template<typename T>
471     static inline T ecb_div_rd (T val, T div)
472     {
473     return val < 0 ? - ((-val + div - 1) / div) : (val ) / div;
474     }
475     template<typename T>
476     static inline T ecb_div_ru (T val, T div)
477     {
478     return val < 0 ? - ((-val ) / div) : (val + div - 1) / div;
479     }
480     #else
481     #define ecb_div_rd(val,div) ((val) < 0 ? - ((-(val) + (div) - 1) / (div)) : ((val) ) / (div))
482     #define ecb_div_ru(val,div) ((val) < 0 ? - ((-(val) ) / (div)) : ((val) + (div) - 1) / (div))
483     #endif
484 sf-exg 1.67
485 root 1.5 #if ecb_cplusplus_does_not_suck
486 root 1.40 /* does not work for local types (http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2008/n2657.htm) */
487 root 1.35 template<typename T, int N>
488     static inline int ecb_array_length (const T (&arr)[N])
489     {
490     return N;
491     }
492 root 1.5 #else
493 root 1.35 #define ecb_array_length(name) (sizeof (name) / sizeof (name [0]))
494 root 1.5 #endif
495    
496 root 1.1 #endif
497