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Revision: 1.18
Committed: Sat Sep 7 23:18:23 2013 UTC (10 years, 8 months ago) by root
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Branch: MAIN
Changes since 1.17: +3 -1 lines
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# User Rev Content
1 root 1.1 /*
2     * libecb - http://software.schmorp.de/pkg/libecb
3     *
4 root 1.11 * Copyright (©) 2009-2012 Marc Alexander Lehmann <libecb@schmorp.de>
5 root 1.1 * Copyright (©) 2011 Emanuele Giaquinta
6     * 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 1.12 /* 16 bits major, 16 bits minor */
34 root 1.17 #define ECB_VERSION 0x00010003
35 root 1.12
36 root 1.2 #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 1.3 #else /* _MSC_VER || __BORLANDC__ */
47 root 1.2 typedef signed __int64 int64_t;
48     typedef unsigned __int64 uint64_t;
49     #endif
50 root 1.12 #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 1.2 #else
60     #include <inttypes.h>
61 root 1.12 #if UINTMAX_MAX > 0xffffffffU
62     #define ECB_PTRSIZE 8
63     #else
64     #define ECB_PTRSIZE 4
65     #endif
66 root 1.2 #endif
67 root 1.1
68 root 1.17 /* work around x32 idiocy by defining proper macros */
69     #if __x86_64 || _M_AMD64
70     #if __ILP32
71     #define ECB_AMD64_X32 1
72     #else
73     #define ECB_AMD64 1
74     #endif
75     #endif
76    
77 root 1.1 /* many compilers define _GNUC_ to some versions but then only implement
78     * what their idiot authors think are the "more important" extensions,
79 root 1.8 * causing enormous grief in return for some better fake benchmark numbers.
80 root 1.1 * or so.
81     * we try to detect these and simply assume they are not gcc - if they have
82     * an issue with that they should have done it right in the first place.
83     */
84     #ifndef ECB_GCC_VERSION
85 root 1.11 #if !defined __GNUC_MINOR__ || defined __INTEL_COMPILER || defined __SUNPRO_C || defined __SUNPRO_CC || defined __llvm__ || defined __clang__
86 root 1.2 #define ECB_GCC_VERSION(major,minor) 0
87     #else
88     #define ECB_GCC_VERSION(major,minor) (__GNUC__ > (major) || (__GNUC__ == (major) && __GNUC_MINOR__ >= (minor)))
89     #endif
90 root 1.1 #endif
91    
92 root 1.13 #define ECB_C (__STDC__+0) /* this assumes that __STDC__ is either empty or a number */
93     #define ECB_C99 (__STDC_VERSION__ >= 199901L)
94     #define ECB_C11 (__STDC_VERSION__ >= 201112L)
95     #define ECB_CPP (__cplusplus+0)
96     #define ECB_CPP11 (__cplusplus >= 201103L)
97    
98 root 1.15 #if ECB_CPP
99     #define ECB_EXTERN_C extern "C"
100     #define ECB_EXTERN_C_BEG ECB_EXTERN_C {
101     #define ECB_EXTERN_C_END }
102     #else
103     #define ECB_EXTERN_C extern
104     #define ECB_EXTERN_C_BEG
105     #define ECB_EXTERN_C_END
106     #endif
107    
108 root 1.4 /*****************************************************************************/
109    
110 root 1.8 /* ECB_NO_THREADS - ecb is not used by multiple threads, ever */
111     /* ECB_NO_SMP - ecb might be used in multiple threads, but only on a single cpu */
112    
113 root 1.11 #if ECB_NO_THREADS
114 root 1.13 #define ECB_NO_SMP 1
115 root 1.11 #endif
116    
117 root 1.13 #if ECB_NO_SMP
118 root 1.8 #define ECB_MEMORY_FENCE do { } while (0)
119     #endif
120    
121 root 1.4 #ifndef ECB_MEMORY_FENCE
122 root 1.11 #if ECB_GCC_VERSION(2,5) || defined __INTEL_COMPILER || (__llvm__ && __GNUC__) || __SUNPRO_C >= 0x5110 || __SUNPRO_CC >= 0x5110
123     #if __i386 || __i386__
124 root 1.5 #define ECB_MEMORY_FENCE __asm__ __volatile__ ("lock; orb $0, -1(%%esp)" : : : "memory")
125 root 1.13 #define ECB_MEMORY_FENCE_ACQUIRE __asm__ __volatile__ ("" : : : "memory")
126     #define ECB_MEMORY_FENCE_RELEASE __asm__ __volatile__ ("")
127 root 1.11 #elif __amd64 || __amd64__ || __x86_64 || __x86_64__
128 root 1.13 #define ECB_MEMORY_FENCE __asm__ __volatile__ ("mfence" : : : "memory")
129     #define ECB_MEMORY_FENCE_ACQUIRE __asm__ __volatile__ ("" : : : "memory")
130     #define ECB_MEMORY_FENCE_RELEASE __asm__ __volatile__ ("")
131 root 1.8 #elif __powerpc__ || __ppc__ || __powerpc64__ || __ppc64__
132 root 1.13 #define ECB_MEMORY_FENCE __asm__ __volatile__ ("sync" : : : "memory")
133 root 1.11 #elif defined __ARM_ARCH_6__ || defined __ARM_ARCH_6J__ \
134     || defined __ARM_ARCH_6K__ || defined __ARM_ARCH_6ZK__
135     #define ECB_MEMORY_FENCE __asm__ __volatile__ ("mcr p15,0,%0,c7,c10,5" : : "r" (0) : "memory")
136     #elif defined __ARM_ARCH_7__ || defined __ARM_ARCH_7A__ \
137 root 1.13 || defined __ARM_ARCH_7M__ || defined __ARM_ARCH_7R__
138     #define ECB_MEMORY_FENCE __asm__ __volatile__ ("dmb" : : : "memory")
139 root 1.11 #elif __sparc || __sparc__
140 root 1.13 #define ECB_MEMORY_FENCE __asm__ __volatile__ ("membar #LoadStore | #LoadLoad | #StoreStore | #StoreLoad" : : : "memory")
141     #define ECB_MEMORY_FENCE_ACQUIRE __asm__ __volatile__ ("membar #LoadStore | #LoadLoad" : : : "memory")
142     #define ECB_MEMORY_FENCE_RELEASE __asm__ __volatile__ ("membar #LoadStore | #StoreStore")
143 root 1.11 #elif defined __s390__ || defined __s390x__
144     #define ECB_MEMORY_FENCE __asm__ __volatile__ ("bcr 15,0" : : : "memory")
145     #elif defined __mips__
146 root 1.18 /* GNU/Linux emulates sync on mips1 architectures, so we force it's use */
147     /* anybody else who still uses mips1 is supposed to send in their version, with detection code. */
148     #define ECB_MEMORY_FENCE __asm__ __volatile__ (".set mips2; sync; .set mips0" : : : "memory")
149 root 1.11 #elif defined __alpha__
150 root 1.13 #define ECB_MEMORY_FENCE __asm__ __volatile__ ("mb" : : : "memory")
151     #elif defined __hppa__
152     #define ECB_MEMORY_FENCE __asm__ __volatile__ ("" : : : "memory")
153     #define ECB_MEMORY_FENCE_RELEASE __asm__ __volatile__ ("")
154     #elif defined __ia64__
155     #define ECB_MEMORY_FENCE __asm__ __volatile__ ("mf" : : : "memory")
156 root 1.4 #endif
157     #endif
158     #endif
159    
160     #ifndef ECB_MEMORY_FENCE
161 root 1.13 #if ECB_GCC_VERSION(4,7)
162     /* see comment below (stdatomic.h) about the C11 memory model. */
163     #define ECB_MEMORY_FENCE __atomic_thread_fence (__ATOMIC_SEQ_CST)
164 root 1.15
165     /* The __has_feature syntax from clang is so misdesigned that we cannot use it
166     * without risking compile time errors with other compilers. We *could*
167     * define our own ecb_clang_has_feature, but I just can't be bothered to work
168 root 1.16 * around this shit time and again.
169 root 1.15 * #elif defined __clang && __has_feature (cxx_atomic)
170     * // see comment below (stdatomic.h) about the C11 memory model.
171     * #define ECB_MEMORY_FENCE __c11_atomic_thread_fence (__ATOMIC_SEQ_CST)
172     */
173    
174 root 1.13 #elif ECB_GCC_VERSION(4,4) || defined __INTEL_COMPILER || defined __clang__
175 root 1.4 #define ECB_MEMORY_FENCE __sync_synchronize ()
176 root 1.7 #elif _MSC_VER >= 1400 /* VC++ 2005 */
177     #pragma intrinsic(_ReadBarrier,_WriteBarrier,_ReadWriteBarrier)
178     #define ECB_MEMORY_FENCE _ReadWriteBarrier ()
179     #define ECB_MEMORY_FENCE_ACQUIRE _ReadWriteBarrier () /* according to msdn, _ReadBarrier is not a load fence */
180     #define ECB_MEMORY_FENCE_RELEASE _WriteBarrier ()
181 root 1.11 #elif defined _WIN32
182 root 1.6 #include <WinNT.h>
183 root 1.7 #define ECB_MEMORY_FENCE MemoryBarrier () /* actually just xchg on x86... scary */
184 root 1.11 #elif __SUNPRO_C >= 0x5110 || __SUNPRO_CC >= 0x5110
185     #include <mbarrier.h>
186     #define ECB_MEMORY_FENCE __machine_rw_barrier ()
187     #define ECB_MEMORY_FENCE_ACQUIRE __machine_r_barrier ()
188     #define ECB_MEMORY_FENCE_RELEASE __machine_w_barrier ()
189     #elif __xlC__
190     #define ECB_MEMORY_FENCE __sync ()
191 root 1.4 #endif
192     #endif
193    
194     #ifndef ECB_MEMORY_FENCE
195 root 1.13 #if ECB_C11 && !defined __STDC_NO_ATOMICS__
196     /* we assume that these memory fences work on all variables/all memory accesses, */
197     /* not just C11 atomics and atomic accesses */
198     #include <stdatomic.h>
199     /* Unfortunately, neither gcc 4.7 nor clang 3.1 generate any instructions for */
200     /* any fence other than seq_cst, which isn't very efficient for us. */
201     /* Why that is, we don't know - either the C11 memory model is quite useless */
202     /* for most usages, or gcc and clang have a bug */
203     /* I *currently* lean towards the latter, and inefficiently implement */
204     /* all three of ecb's fences as a seq_cst fence */
205     #define ECB_MEMORY_FENCE atomic_thread_fence (memory_order_seq_cst)
206     #endif
207     #endif
208    
209     #ifndef ECB_MEMORY_FENCE
210 root 1.8 #if !ECB_AVOID_PTHREADS
211     /*
212     * if you get undefined symbol references to pthread_mutex_lock,
213     * or failure to find pthread.h, then you should implement
214     * the ECB_MEMORY_FENCE operations for your cpu/compiler
215     * OR provide pthread.h and link against the posix thread library
216     * of your system.
217     */
218     #include <pthread.h>
219     #define ECB_NEEDS_PTHREADS 1
220     #define ECB_MEMORY_FENCE_NEEDS_PTHREADS 1
221    
222     static pthread_mutex_t ecb_mf_lock = PTHREAD_MUTEX_INITIALIZER;
223     #define ECB_MEMORY_FENCE do { pthread_mutex_lock (&ecb_mf_lock); pthread_mutex_unlock (&ecb_mf_lock); } while (0)
224     #endif
225     #endif
226 root 1.4
227 root 1.11 #if !defined ECB_MEMORY_FENCE_ACQUIRE && defined ECB_MEMORY_FENCE
228 root 1.4 #define ECB_MEMORY_FENCE_ACQUIRE ECB_MEMORY_FENCE
229 root 1.8 #endif
230    
231 root 1.11 #if !defined ECB_MEMORY_FENCE_RELEASE && defined ECB_MEMORY_FENCE
232 root 1.4 #define ECB_MEMORY_FENCE_RELEASE ECB_MEMORY_FENCE
233     #endif
234    
235     /*****************************************************************************/
236    
237 root 1.2 #if __cplusplus
238     #define ecb_inline static inline
239     #elif ECB_GCC_VERSION(2,5)
240     #define ecb_inline static __inline__
241     #elif ECB_C99
242     #define ecb_inline static inline
243     #else
244     #define ecb_inline static
245     #endif
246    
247     #if ECB_GCC_VERSION(3,3)
248     #define ecb_restrict __restrict__
249     #elif ECB_C99
250     #define ecb_restrict restrict
251 root 1.1 #else
252 root 1.2 #define ecb_restrict
253 root 1.1 #endif
254    
255 root 1.2 typedef int ecb_bool;
256    
257 root 1.1 #define ECB_CONCAT_(a, b) a ## b
258     #define ECB_CONCAT(a, b) ECB_CONCAT_(a, b)
259     #define ECB_STRINGIFY_(a) # a
260     #define ECB_STRINGIFY(a) ECB_STRINGIFY_(a)
261    
262 root 1.2 #define ecb_function_ ecb_inline
263 root 1.1
264     #if ECB_GCC_VERSION(3,1)
265 root 1.2 #define ecb_attribute(attrlist) __attribute__(attrlist)
266     #define ecb_is_constant(expr) __builtin_constant_p (expr)
267     #define ecb_expect(expr,value) __builtin_expect ((expr),(value))
268     #define ecb_prefetch(addr,rw,locality) __builtin_prefetch (addr, rw, locality)
269     #else
270     #define ecb_attribute(attrlist)
271     #define ecb_is_constant(expr) 0
272     #define ecb_expect(expr,value) (expr)
273     #define ecb_prefetch(addr,rw,locality)
274 root 1.1 #endif
275    
276     /* no emulation for ecb_decltype */
277     #if ECB_GCC_VERSION(4,5)
278 root 1.2 #define ecb_decltype(x) __decltype(x)
279 root 1.1 #elif ECB_GCC_VERSION(3,0)
280 root 1.2 #define ecb_decltype(x) __typeof(x)
281 root 1.1 #endif
282    
283     #define ecb_noinline ecb_attribute ((__noinline__))
284     #define ecb_unused ecb_attribute ((__unused__))
285     #define ecb_const ecb_attribute ((__const__))
286     #define ecb_pure ecb_attribute ((__pure__))
287    
288 root 1.13 #if ECB_C11
289     #define ecb_noreturn _Noreturn
290     #else
291     #define ecb_noreturn ecb_attribute ((__noreturn__))
292     #endif
293    
294 root 1.2 #if ECB_GCC_VERSION(4,3)
295     #define ecb_artificial ecb_attribute ((__artificial__))
296     #define ecb_hot ecb_attribute ((__hot__))
297     #define ecb_cold ecb_attribute ((__cold__))
298     #else
299     #define ecb_artificial
300     #define ecb_hot
301     #define ecb_cold
302     #endif
303    
304     /* put around conditional expressions if you are very sure that the */
305     /* expression is mostly true or mostly false. note that these return */
306     /* booleans, not the expression. */
307 root 1.1 #define ecb_expect_false(expr) ecb_expect (!!(expr), 0)
308     #define ecb_expect_true(expr) ecb_expect (!!(expr), 1)
309 root 1.2 /* for compatibility to the rest of the world */
310 root 1.1 #define ecb_likely(expr) ecb_expect_true (expr)
311     #define ecb_unlikely(expr) ecb_expect_false (expr)
312    
313     /* count trailing zero bits and count # of one bits */
314     #if ECB_GCC_VERSION(3,4)
315 root 1.2 /* we assume int == 32 bit, long == 32 or 64 bit and long long == 64 bit */
316     #define ecb_ld32(x) (__builtin_clz (x) ^ 31)
317     #define ecb_ld64(x) (__builtin_clzll (x) ^ 63)
318     #define ecb_ctz32(x) __builtin_ctz (x)
319     #define ecb_ctz64(x) __builtin_ctzll (x)
320     #define ecb_popcount32(x) __builtin_popcount (x)
321     /* no popcountll */
322 root 1.1 #else
323 root 1.2 ecb_function_ int ecb_ctz32 (uint32_t x) ecb_const;
324     ecb_function_ int
325     ecb_ctz32 (uint32_t x)
326     {
327     int r = 0;
328    
329     x &= ~x + 1; /* this isolates the lowest bit */
330    
331 root 1.3 #if ECB_branchless_on_i386
332     r += !!(x & 0xaaaaaaaa) << 0;
333     r += !!(x & 0xcccccccc) << 1;
334     r += !!(x & 0xf0f0f0f0) << 2;
335     r += !!(x & 0xff00ff00) << 3;
336     r += !!(x & 0xffff0000) << 4;
337     #else
338 root 1.2 if (x & 0xaaaaaaaa) r += 1;
339     if (x & 0xcccccccc) r += 2;
340     if (x & 0xf0f0f0f0) r += 4;
341     if (x & 0xff00ff00) r += 8;
342     if (x & 0xffff0000) r += 16;
343 root 1.3 #endif
344 root 1.2
345     return r;
346     }
347    
348     ecb_function_ int ecb_ctz64 (uint64_t x) ecb_const;
349     ecb_function_ int
350     ecb_ctz64 (uint64_t x)
351     {
352     int shift = x & 0xffffffffU ? 0 : 32;
353 root 1.3 return ecb_ctz32 (x >> shift) + shift;
354 root 1.2 }
355    
356     ecb_function_ int ecb_popcount32 (uint32_t x) ecb_const;
357     ecb_function_ int
358     ecb_popcount32 (uint32_t x)
359     {
360     x -= (x >> 1) & 0x55555555;
361     x = ((x >> 2) & 0x33333333) + (x & 0x33333333);
362     x = ((x >> 4) + x) & 0x0f0f0f0f;
363     x *= 0x01010101;
364    
365     return x >> 24;
366     }
367    
368     ecb_function_ int ecb_ld32 (uint32_t x) ecb_const;
369     ecb_function_ int ecb_ld32 (uint32_t x)
370     {
371 root 1.3 int r = 0;
372 root 1.2
373 root 1.3 if (x >> 16) { x >>= 16; r += 16; }
374     if (x >> 8) { x >>= 8; r += 8; }
375     if (x >> 4) { x >>= 4; r += 4; }
376     if (x >> 2) { x >>= 2; r += 2; }
377     if (x >> 1) { r += 1; }
378 root 1.2
379     return r;
380     }
381    
382     ecb_function_ int ecb_ld64 (uint64_t x) ecb_const;
383     ecb_function_ int ecb_ld64 (uint64_t x)
384     {
385 root 1.3 int r = 0;
386 root 1.2
387 root 1.3 if (x >> 32) { x >>= 32; r += 32; }
388 root 1.1
389 root 1.3 return r + ecb_ld32 (x);
390 root 1.2 }
391     #endif
392 root 1.1
393 root 1.12 ecb_function_ ecb_bool ecb_is_pot32 (uint32_t x) ecb_const;
394     ecb_function_ ecb_bool ecb_is_pot32 (uint32_t x) { return !(x & (x - 1)); }
395     ecb_function_ ecb_bool ecb_is_pot64 (uint64_t x) ecb_const;
396     ecb_function_ ecb_bool ecb_is_pot64 (uint64_t x) { return !(x & (x - 1)); }
397    
398 root 1.11 ecb_function_ uint8_t ecb_bitrev8 (uint8_t x) ecb_const;
399     ecb_function_ uint8_t ecb_bitrev8 (uint8_t x)
400     {
401     return ( (x * 0x0802U & 0x22110U)
402     | (x * 0x8020U & 0x88440U)) * 0x10101U >> 16;
403     }
404    
405     ecb_function_ uint16_t ecb_bitrev16 (uint16_t x) ecb_const;
406     ecb_function_ uint16_t ecb_bitrev16 (uint16_t x)
407     {
408     x = ((x >> 1) & 0x5555) | ((x & 0x5555) << 1);
409     x = ((x >> 2) & 0x3333) | ((x & 0x3333) << 2);
410     x = ((x >> 4) & 0x0f0f) | ((x & 0x0f0f) << 4);
411     x = ( x >> 8 ) | ( x << 8);
412    
413     return x;
414     }
415    
416     ecb_function_ uint32_t ecb_bitrev32 (uint32_t x) ecb_const;
417     ecb_function_ uint32_t ecb_bitrev32 (uint32_t x)
418     {
419     x = ((x >> 1) & 0x55555555) | ((x & 0x55555555) << 1);
420     x = ((x >> 2) & 0x33333333) | ((x & 0x33333333) << 2);
421     x = ((x >> 4) & 0x0f0f0f0f) | ((x & 0x0f0f0f0f) << 4);
422     x = ((x >> 8) & 0x00ff00ff) | ((x & 0x00ff00ff) << 8);
423     x = ( x >> 16 ) | ( x << 16);
424    
425     return x;
426     }
427    
428 root 1.2 /* popcount64 is only available on 64 bit cpus as gcc builtin */
429     /* so for this version we are lazy */
430     ecb_function_ int ecb_popcount64 (uint64_t x) ecb_const;
431     ecb_function_ int
432     ecb_popcount64 (uint64_t x)
433 root 1.1 {
434 root 1.2 return ecb_popcount32 (x) + ecb_popcount32 (x >> 32);
435 root 1.1 }
436    
437 root 1.3 ecb_inline uint8_t ecb_rotl8 (uint8_t x, unsigned int count) ecb_const;
438     ecb_inline uint8_t ecb_rotr8 (uint8_t x, unsigned int count) ecb_const;
439     ecb_inline uint16_t ecb_rotl16 (uint16_t x, unsigned int count) ecb_const;
440     ecb_inline uint16_t ecb_rotr16 (uint16_t x, unsigned int count) ecb_const;
441     ecb_inline uint32_t ecb_rotl32 (uint32_t x, unsigned int count) ecb_const;
442     ecb_inline uint32_t ecb_rotr32 (uint32_t x, unsigned int count) ecb_const;
443     ecb_inline uint64_t ecb_rotl64 (uint64_t x, unsigned int count) ecb_const;
444     ecb_inline uint64_t ecb_rotr64 (uint64_t x, unsigned int count) ecb_const;
445    
446     ecb_inline uint8_t ecb_rotl8 (uint8_t x, unsigned int count) { return (x >> ( 8 - count)) | (x << count); }
447     ecb_inline uint8_t ecb_rotr8 (uint8_t x, unsigned int count) { return (x << ( 8 - count)) | (x >> count); }
448     ecb_inline uint16_t ecb_rotl16 (uint16_t x, unsigned int count) { return (x >> (16 - count)) | (x << count); }
449     ecb_inline uint16_t ecb_rotr16 (uint16_t x, unsigned int count) { return (x << (16 - count)) | (x >> count); }
450     ecb_inline uint32_t ecb_rotl32 (uint32_t x, unsigned int count) { return (x >> (32 - count)) | (x << count); }
451     ecb_inline uint32_t ecb_rotr32 (uint32_t x, unsigned int count) { return (x << (32 - count)) | (x >> count); }
452     ecb_inline uint64_t ecb_rotl64 (uint64_t x, unsigned int count) { return (x >> (64 - count)) | (x << count); }
453     ecb_inline uint64_t ecb_rotr64 (uint64_t x, unsigned int count) { return (x << (64 - count)) | (x >> count); }
454    
455 root 1.1 #if ECB_GCC_VERSION(4,3)
456 root 1.2 #define ecb_bswap16(x) (__builtin_bswap32 (x) >> 16)
457     #define ecb_bswap32(x) __builtin_bswap32 (x)
458     #define ecb_bswap64(x) __builtin_bswap64 (x)
459 root 1.1 #else
460 root 1.3 ecb_function_ uint16_t ecb_bswap16 (uint16_t x) ecb_const;
461     ecb_function_ uint16_t
462     ecb_bswap16 (uint16_t x)
463 root 1.2 {
464 root 1.3 return ecb_rotl16 (x, 8);
465 root 1.2 }
466    
467     ecb_function_ uint32_t ecb_bswap32 (uint32_t x) ecb_const;
468     ecb_function_ uint32_t
469     ecb_bswap32 (uint32_t x)
470     {
471 root 1.3 return (((uint32_t)ecb_bswap16 (x)) << 16) | ecb_bswap16 (x >> 16);
472 root 1.2 }
473    
474     ecb_function_ uint64_t ecb_bswap64 (uint64_t x) ecb_const;
475     ecb_function_ uint64_t
476     ecb_bswap64 (uint64_t x)
477     {
478 root 1.3 return (((uint64_t)ecb_bswap32 (x)) << 32) | ecb_bswap32 (x >> 32);
479 root 1.2 }
480 root 1.1 #endif
481    
482     #if ECB_GCC_VERSION(4,5)
483 root 1.2 #define ecb_unreachable() __builtin_unreachable ()
484 root 1.1 #else
485 root 1.2 /* this seems to work fine, but gcc always emits a warning for it :/ */
486 root 1.11 ecb_inline void ecb_unreachable (void) ecb_noreturn;
487     ecb_inline void ecb_unreachable (void) { }
488 root 1.1 #endif
489    
490 root 1.2 /* try to tell the compiler that some condition is definitely true */
491 root 1.14 #define ecb_assume(cond) if (!(cond)) ecb_unreachable (); else 0
492 root 1.2
493 root 1.11 ecb_inline unsigned char ecb_byteorder_helper (void) ecb_const;
494     ecb_inline unsigned char
495 root 1.1 ecb_byteorder_helper (void)
496     {
497 root 1.14 /* the union code still generates code under pressure in gcc, */
498 root 1.16 /* but less than using pointers, and always seems to */
499 root 1.14 /* successfully return a constant. */
500     /* the reason why we have this horrible preprocessor mess */
501     /* is to avoid it in all cases, at least on common architectures */
502 root 1.16 /* or when using a recent enough gcc version (>= 4.6) */
503 root 1.14 #if __i386 || __i386__ || _M_X86 || __amd64 || __amd64__ || _M_X64
504     return 0x44;
505     #elif __BYTE_ORDER__ && __BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__
506     return 0x44;
507     #elif __BYTE_ORDER__ && __BYTE_ORDER__ == __ORDER_BIG_ENDIAN__
508 root 1.16 return 0x11;
509 root 1.14 #else
510     union
511     {
512     uint32_t i;
513     uint8_t c;
514     } u = { 0x11223344 };
515     return u.c;
516     #endif
517 root 1.1 }
518    
519 root 1.11 ecb_inline ecb_bool ecb_big_endian (void) ecb_const;
520     ecb_inline ecb_bool ecb_big_endian (void) { return ecb_byteorder_helper () == 0x11; }
521     ecb_inline ecb_bool ecb_little_endian (void) ecb_const;
522     ecb_inline ecb_bool ecb_little_endian (void) { return ecb_byteorder_helper () == 0x44; }
523 root 1.1
524 root 1.2 #if ECB_GCC_VERSION(3,0) || ECB_C99
525     #define ecb_mod(m,n) ((m) % (n) + ((m) % (n) < 0 ? (n) : 0))
526 root 1.1 #else
527 root 1.2 #define ecb_mod(m,n) ((m) < 0 ? ((n) - 1 - ((-1 - (m)) % (n))) : ((m) % (n)))
528 root 1.1 #endif
529    
530 root 1.10 #if __cplusplus
531     template<typename T>
532     static inline T ecb_div_rd (T val, T div)
533     {
534     return val < 0 ? - ((-val + div - 1) / div) : (val ) / div;
535     }
536     template<typename T>
537     static inline T ecb_div_ru (T val, T div)
538     {
539     return val < 0 ? - ((-val ) / div) : (val + div - 1) / div;
540     }
541     #else
542     #define ecb_div_rd(val,div) ((val) < 0 ? - ((-(val) + (div) - 1) / (div)) : ((val) ) / (div))
543     #define ecb_div_ru(val,div) ((val) < 0 ? - ((-(val) ) / (div)) : ((val) + (div) - 1) / (div))
544     #endif
545    
546 root 1.1 #if ecb_cplusplus_does_not_suck
547 root 1.2 /* does not work for local types (http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2008/n2657.htm) */
548     template<typename T, int N>
549     static inline int ecb_array_length (const T (&arr)[N])
550     {
551     return N;
552     }
553 root 1.1 #else
554 root 1.2 #define ecb_array_length(name) (sizeof (name) / sizeof (name [0]))
555 root 1.1 #endif
556    
557 root 1.15 /*******************************************************************************/
558     /* floating point stuff, can be disabled by defining ECB_NO_LIBM */
559    
560     /* basically, everything uses "ieee pure-endian" floating point numbers */
561     /* the only noteworthy exception is ancient armle, which uses order 43218765 */
562     #if 0 \
563     || __i386 || __i386__ \
564     || __amd64 || __amd64__ || __x86_64 || __x86_64__ \
565     || __powerpc__ || __ppc__ || __powerpc64__ || __ppc64__ \
566     || defined __arm__ && defined __ARM_EABI__ \
567     || defined __s390__ || defined __s390x__ \
568     || defined __mips__ \
569     || defined __alpha__ \
570     || defined __hppa__ \
571     || defined __ia64__ \
572     || defined _M_IX86 || defined _M_AMD64 || defined _M_IA64
573     #define ECB_STDFP 1
574     #include <string.h> /* for memcpy */
575     #else
576     #define ECB_STDFP 0
577     #include <math.h> /* for frexp*, ldexp* */
578     #endif
579    
580     #ifndef ECB_NO_LIBM
581    
582     /* convert a float to ieee single/binary32 */
583     ecb_function_ uint32_t ecb_float_to_binary32 (float x) ecb_const;
584     ecb_function_ uint32_t
585     ecb_float_to_binary32 (float x)
586     {
587     uint32_t r;
588    
589     #if ECB_STDFP
590     memcpy (&r, &x, 4);
591     #else
592     /* slow emulation, works for anything but -0 */
593     uint32_t m;
594     int e;
595    
596     if (x == 0e0f ) return 0x00000000U;
597     if (x > +3.40282346638528860e+38f) return 0x7f800000U;
598     if (x < -3.40282346638528860e+38f) return 0xff800000U;
599     if (x != x ) return 0x7fbfffffU;
600    
601     m = frexpf (x, &e) * 0x1000000U;
602    
603     r = m & 0x80000000U;
604    
605     if (r)
606     m = -m;
607    
608     if (e <= -126)
609     {
610     m &= 0xffffffU;
611     m >>= (-125 - e);
612     e = -126;
613     }
614    
615     r |= (e + 126) << 23;
616     r |= m & 0x7fffffU;
617     #endif
618    
619     return r;
620     }
621    
622     /* converts an ieee single/binary32 to a float */
623     ecb_function_ float ecb_binary32_to_float (uint32_t x) ecb_const;
624     ecb_function_ float
625     ecb_binary32_to_float (uint32_t x)
626     {
627     float r;
628    
629     #if ECB_STDFP
630     memcpy (&r, &x, 4);
631     #else
632     /* emulation, only works for normals and subnormals and +0 */
633     int neg = x >> 31;
634     int e = (x >> 23) & 0xffU;
635    
636     x &= 0x7fffffU;
637    
638     if (e)
639     x |= 0x800000U;
640     else
641     e = 1;
642    
643     /* we distrust ldexpf a bit and do the 2**-24 scaling by an extra multiply */
644     r = ldexpf (x * (0.5f / 0x800000U), e - 126);
645    
646     r = neg ? -r : r;
647     #endif
648    
649     return r;
650     }
651    
652     /* convert a double to ieee double/binary64 */
653     ecb_function_ uint64_t ecb_double_to_binary64 (double x) ecb_const;
654     ecb_function_ uint64_t
655     ecb_double_to_binary64 (double x)
656     {
657     uint64_t r;
658    
659     #if ECB_STDFP
660     memcpy (&r, &x, 8);
661     #else
662     /* slow emulation, works for anything but -0 */
663     uint64_t m;
664     int e;
665    
666     if (x == 0e0 ) return 0x0000000000000000U;
667     if (x > +1.79769313486231470e+308) return 0x7ff0000000000000U;
668     if (x < -1.79769313486231470e+308) return 0xfff0000000000000U;
669     if (x != x ) return 0X7ff7ffffffffffffU;
670    
671     m = frexp (x, &e) * 0x20000000000000U;
672    
673     r = m & 0x8000000000000000;;
674    
675     if (r)
676     m = -m;
677    
678     if (e <= -1022)
679     {
680     m &= 0x1fffffffffffffU;
681     m >>= (-1021 - e);
682     e = -1022;
683     }
684    
685     r |= ((uint64_t)(e + 1022)) << 52;
686     r |= m & 0xfffffffffffffU;
687     #endif
688    
689     return r;
690     }
691    
692     /* converts an ieee double/binary64 to a double */
693     ecb_function_ double ecb_binary64_to_double (uint64_t x) ecb_const;
694     ecb_function_ double
695     ecb_binary64_to_double (uint64_t x)
696     {
697     double r;
698    
699     #if ECB_STDFP
700     memcpy (&r, &x, 8);
701     #else
702     /* emulation, only works for normals and subnormals and +0 */
703     int neg = x >> 63;
704     int e = (x >> 52) & 0x7ffU;
705    
706     x &= 0xfffffffffffffU;
707    
708     if (e)
709     x |= 0x10000000000000U;
710     else
711     e = 1;
712    
713     /* we distrust ldexp a bit and do the 2**-53 scaling by an extra multiply */
714     r = ldexp (x * (0.5 / 0x10000000000000U), e - 1022);
715    
716     r = neg ? -r : r;
717     #endif
718    
719     return r;
720     }
721    
722     #endif
723    
724 root 1.1 #endif
725