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Revision: 1.111
Committed: Wed Jul 25 09:24:57 2012 UTC (11 years, 10 months ago) by sf-exg
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Branch: MAIN
Changes since 1.110: +2 -2 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 root 1.110 #define ECB_VERSION 0x00010002
35 root 1.87
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 1.44 #else
60     #include <inttypes.h>
61 root 1.87 #if UINTMAX_MAX > 0xffffffffU
62     #define ECB_PTRSIZE 8
63     #else
64     #define ECB_PTRSIZE 4
65     #endif
66 root 1.44 #endif
67 root 1.6
68 root 1.12 /* many compilers define _GNUC_ to some versions but then only implement
69     * what their idiot authors think are the "more important" extensions,
70 sf-exg 1.59 * causing enormous grief in return for some better fake benchmark numbers.
71 root 1.18 * or so.
72 root 1.12 * we try to detect these and simply assume they are not gcc - if they have
73     * an issue with that they should have done it right in the first place.
74     */
75 root 1.14 #ifndef ECB_GCC_VERSION
76 root 1.85 #if !defined __GNUC_MINOR__ || defined __INTEL_COMPILER || defined __SUNPRO_C || defined __SUNPRO_CC || defined __llvm__ || defined __clang__
77 root 1.37 #define ECB_GCC_VERSION(major,minor) 0
78     #else
79     #define ECB_GCC_VERSION(major,minor) (__GNUC__ > (major) || (__GNUC__ == (major) && __GNUC_MINOR__ >= (minor)))
80     #endif
81 root 1.12 #endif
82 root 1.1
83 root 1.91 #define ECB_C (__STDC__+0) /* this assumes that __STDC__ is either empty or a number */
84     #define ECB_C99 (__STDC_VERSION__ >= 199901L)
85     #define ECB_C11 (__STDC_VERSION__ >= 201112L)
86     #define ECB_CPP (__cplusplus+0)
87     #define ECB_CPP11 (__cplusplus >= 201103L)
88 root 1.90
89 root 1.102 #if ECB_CPP
90     #define ECB_EXTERN_C extern "C"
91     #define ECB_EXTERN_C_BEG ECB_EXTERN_C {
92     #define ECB_EXTERN_C_END }
93     #else
94     #define ECB_EXTERN_C extern
95     #define ECB_EXTERN_C_BEG
96     #define ECB_EXTERN_C_END
97     #endif
98    
99 root 1.52 /*****************************************************************************/
100    
101 root 1.58 /* ECB_NO_THREADS - ecb is not used by multiple threads, ever */
102     /* ECB_NO_SMP - ecb might be used in multiple threads, but only on a single cpu */
103    
104 root 1.79 #if ECB_NO_THREADS
105 root 1.95 #define ECB_NO_SMP 1
106 root 1.79 #endif
107    
108 root 1.93 #if ECB_NO_SMP
109 root 1.64 #define ECB_MEMORY_FENCE do { } while (0)
110 root 1.58 #endif
111    
112 root 1.52 #ifndef ECB_MEMORY_FENCE
113 root 1.85 #if ECB_GCC_VERSION(2,5) || defined __INTEL_COMPILER || (__llvm__ && __GNUC__) || __SUNPRO_C >= 0x5110 || __SUNPRO_CC >= 0x5110
114 root 1.73 #if __i386 || __i386__
115 root 1.54 #define ECB_MEMORY_FENCE __asm__ __volatile__ ("lock; orb $0, -1(%%esp)" : : : "memory")
116 root 1.94 #define ECB_MEMORY_FENCE_ACQUIRE __asm__ __volatile__ ("" : : : "memory")
117     #define ECB_MEMORY_FENCE_RELEASE __asm__ __volatile__ ("")
118 root 1.73 #elif __amd64 || __amd64__ || __x86_64 || __x86_64__
119 root 1.94 #define ECB_MEMORY_FENCE __asm__ __volatile__ ("mfence" : : : "memory")
120     #define ECB_MEMORY_FENCE_ACQUIRE __asm__ __volatile__ ("" : : : "memory")
121     #define ECB_MEMORY_FENCE_RELEASE __asm__ __volatile__ ("")
122 root 1.63 #elif __powerpc__ || __ppc__ || __powerpc64__ || __ppc64__
123 root 1.94 #define ECB_MEMORY_FENCE __asm__ __volatile__ ("sync" : : : "memory")
124 root 1.85 #elif defined __ARM_ARCH_6__ || defined __ARM_ARCH_6J__ \
125     || defined __ARM_ARCH_6K__ || defined __ARM_ARCH_6ZK__
126 root 1.84 #define ECB_MEMORY_FENCE __asm__ __volatile__ ("mcr p15,0,%0,c7,c10,5" : : "r" (0) : "memory")
127 root 1.85 #elif defined __ARM_ARCH_7__ || defined __ARM_ARCH_7A__ \
128 root 1.94 || defined __ARM_ARCH_7M__ || defined __ARM_ARCH_7R__
129     #define ECB_MEMORY_FENCE __asm__ __volatile__ ("dmb" : : : "memory")
130 root 1.73 #elif __sparc || __sparc__
131 root 1.94 #define ECB_MEMORY_FENCE __asm__ __volatile__ ("membar #LoadStore | #LoadLoad | #StoreStore | #StoreLoad" : : : "memory")
132     #define ECB_MEMORY_FENCE_ACQUIRE __asm__ __volatile__ ("membar #LoadStore | #LoadLoad" : : : "memory")
133     #define ECB_MEMORY_FENCE_RELEASE __asm__ __volatile__ ("membar #LoadStore | #StoreStore")
134 root 1.85 #elif defined __s390__ || defined __s390x__
135 root 1.77 #define ECB_MEMORY_FENCE __asm__ __volatile__ ("bcr 15,0" : : : "memory")
136 root 1.85 #elif defined __mips__
137 root 1.94 #define ECB_MEMORY_FENCE __asm__ __volatile__ ("sync" : : : "memory")
138 root 1.86 #elif defined __alpha__
139 root 1.94 #define ECB_MEMORY_FENCE __asm__ __volatile__ ("mb" : : : "memory")
140     #elif defined __hppa__
141     #define ECB_MEMORY_FENCE __asm__ __volatile__ ("" : : : "memory")
142     #define ECB_MEMORY_FENCE_RELEASE __asm__ __volatile__ ("")
143     #elif defined __ia64__
144     #define ECB_MEMORY_FENCE __asm__ __volatile__ ("mf" : : : "memory")
145 root 1.52 #endif
146     #endif
147     #endif
148    
149     #ifndef ECB_MEMORY_FENCE
150 root 1.93 #if ECB_GCC_VERSION(4,7)
151 root 1.97 /* see comment below (stdatomic.h) about the C11 memory model. */
152 root 1.93 #define ECB_MEMORY_FENCE __atomic_thread_fence (__ATOMIC_SEQ_CST)
153 root 1.110
154     /* The __has_feature syntax from clang is so misdesigned that we cannot use it
155     * without risking compile time errors with other compilers. We *could*
156     * define our own ecb_clang_has_feature, but I just can't be bothered to work
157     * around * this shit time and again.
158     * #elif defined __clang && __has_feature (cxx_atomic)
159     * // see comment below (stdatomic.h) about the C11 memory model.
160     * #define ECB_MEMORY_FENCE __c11_atomic_thread_fence (__ATOMIC_SEQ_CST)
161     */
162    
163 root 1.93 #elif ECB_GCC_VERSION(4,4) || defined __INTEL_COMPILER || defined __clang__
164 root 1.52 #define ECB_MEMORY_FENCE __sync_synchronize ()
165 root 1.57 #elif _MSC_VER >= 1400 /* VC++ 2005 */
166     #pragma intrinsic(_ReadBarrier,_WriteBarrier,_ReadWriteBarrier)
167     #define ECB_MEMORY_FENCE _ReadWriteBarrier ()
168     #define ECB_MEMORY_FENCE_ACQUIRE _ReadWriteBarrier () /* according to msdn, _ReadBarrier is not a load fence */
169     #define ECB_MEMORY_FENCE_RELEASE _WriteBarrier ()
170 root 1.85 #elif defined _WIN32
171 root 1.55 #include <WinNT.h>
172 root 1.57 #define ECB_MEMORY_FENCE MemoryBarrier () /* actually just xchg on x86... scary */
173 root 1.72 #elif __SUNPRO_C >= 0x5110 || __SUNPRO_CC >= 0x5110
174     #include <mbarrier.h>
175     #define ECB_MEMORY_FENCE __machine_rw_barrier ()
176     #define ECB_MEMORY_FENCE_ACQUIRE __machine_r_barrier ()
177     #define ECB_MEMORY_FENCE_RELEASE __machine_w_barrier ()
178 root 1.82 #elif __xlC__
179 root 1.83 #define ECB_MEMORY_FENCE __sync ()
180 root 1.52 #endif
181     #endif
182    
183 root 1.53 #ifndef ECB_MEMORY_FENCE
184 root 1.94 #if ECB_C11 && !defined __STDC_NO_ATOMICS__
185     /* we assume that these memory fences work on all variables/all memory accesses, */
186     /* not just C11 atomics and atomic accesses */
187     #include <stdatomic.h>
188 root 1.97 /* Unfortunately, neither gcc 4.7 nor clang 3.1 generate any instructions for */
189     /* any fence other than seq_cst, which isn't very efficient for us. */
190     /* Why that is, we don't know - either the C11 memory model is quite useless */
191     /* for most usages, or gcc and clang have a bug */
192     /* I *currently* lean towards the latter, and inefficiently implement */
193     /* all three of ecb's fences as a seq_cst fence */
194 root 1.94 #define ECB_MEMORY_FENCE atomic_thread_fence (memory_order_seq_cst)
195     #endif
196     #endif
197    
198     #ifndef ECB_MEMORY_FENCE
199 root 1.62 #if !ECB_AVOID_PTHREADS
200     /*
201     * if you get undefined symbol references to pthread_mutex_lock,
202     * or failure to find pthread.h, then you should implement
203     * the ECB_MEMORY_FENCE operations for your cpu/compiler
204     * OR provide pthread.h and link against the posix thread library
205     * of your system.
206     */
207     #include <pthread.h>
208     #define ECB_NEEDS_PTHREADS 1
209     #define ECB_MEMORY_FENCE_NEEDS_PTHREADS 1
210 root 1.52
211 root 1.62 static pthread_mutex_t ecb_mf_lock = PTHREAD_MUTEX_INITIALIZER;
212     #define ECB_MEMORY_FENCE do { pthread_mutex_lock (&ecb_mf_lock); pthread_mutex_unlock (&ecb_mf_lock); } while (0)
213     #endif
214     #endif
215    
216 root 1.85 #if !defined ECB_MEMORY_FENCE_ACQUIRE && defined ECB_MEMORY_FENCE
217 root 1.52 #define ECB_MEMORY_FENCE_ACQUIRE ECB_MEMORY_FENCE
218 root 1.62 #endif
219    
220 root 1.85 #if !defined ECB_MEMORY_FENCE_RELEASE && defined ECB_MEMORY_FENCE
221 root 1.52 #define ECB_MEMORY_FENCE_RELEASE ECB_MEMORY_FENCE
222     #endif
223    
224     /*****************************************************************************/
225    
226 root 1.39 #if __cplusplus
227 root 1.46 #define ecb_inline static inline
228 root 1.38 #elif ECB_GCC_VERSION(2,5)
229 root 1.46 #define ecb_inline static __inline__
230 root 1.39 #elif ECB_C99
231 root 1.46 #define ecb_inline static inline
232 root 1.29 #else
233 root 1.46 #define ecb_inline static
234 root 1.38 #endif
235    
236     #if ECB_GCC_VERSION(3,3)
237     #define ecb_restrict __restrict__
238 root 1.39 #elif ECB_C99
239 root 1.38 #define ecb_restrict restrict
240     #else
241     #define ecb_restrict
242 root 1.4 #endif
243    
244 root 1.38 typedef int ecb_bool;
245    
246 root 1.8 #define ECB_CONCAT_(a, b) a ## b
247     #define ECB_CONCAT(a, b) ECB_CONCAT_(a, b)
248     #define ECB_STRINGIFY_(a) # a
249     #define ECB_STRINGIFY(a) ECB_STRINGIFY_(a)
250    
251 root 1.46 #define ecb_function_ ecb_inline
252 root 1.3
253 root 1.1 #if ECB_GCC_VERSION(3,1)
254 root 1.37 #define ecb_attribute(attrlist) __attribute__(attrlist)
255     #define ecb_is_constant(expr) __builtin_constant_p (expr)
256     #define ecb_expect(expr,value) __builtin_expect ((expr),(value))
257     #define ecb_prefetch(addr,rw,locality) __builtin_prefetch (addr, rw, locality)
258     #else
259     #define ecb_attribute(attrlist)
260     #define ecb_is_constant(expr) 0
261     #define ecb_expect(expr,value) (expr)
262     #define ecb_prefetch(addr,rw,locality)
263 root 1.1 #endif
264    
265 root 1.2 /* no emulation for ecb_decltype */
266 root 1.1 #if ECB_GCC_VERSION(4,5)
267 root 1.37 #define ecb_decltype(x) __decltype(x)
268 root 1.1 #elif ECB_GCC_VERSION(3,0)
269 root 1.39 #define ecb_decltype(x) __typeof(x)
270 root 1.1 #endif
271    
272 root 1.24 #define ecb_noinline ecb_attribute ((__noinline__))
273     #define ecb_unused ecb_attribute ((__unused__))
274     #define ecb_const ecb_attribute ((__const__))
275     #define ecb_pure ecb_attribute ((__pure__))
276 root 1.35
277 root 1.90 #if ECB_C11
278     #define ecb_noreturn _Noreturn
279     #else
280     #define ecb_noreturn ecb_attribute ((__noreturn__))
281     #endif
282    
283 root 1.35 #if ECB_GCC_VERSION(4,3)
284 root 1.39 #define ecb_artificial ecb_attribute ((__artificial__))
285     #define ecb_hot ecb_attribute ((__hot__))
286     #define ecb_cold ecb_attribute ((__cold__))
287 root 1.35 #else
288     #define ecb_artificial
289     #define ecb_hot
290     #define ecb_cold
291     #endif
292 root 1.1
293 root 1.39 /* put around conditional expressions if you are very sure that the */
294     /* expression is mostly true or mostly false. note that these return */
295     /* booleans, not the expression. */
296 root 1.33 #define ecb_expect_false(expr) ecb_expect (!!(expr), 0)
297     #define ecb_expect_true(expr) ecb_expect (!!(expr), 1)
298 root 1.36 /* for compatibility to the rest of the world */
299 root 1.33 #define ecb_likely(expr) ecb_expect_true (expr)
300     #define ecb_unlikely(expr) ecb_expect_false (expr)
301 root 1.1
302 root 1.3 /* count trailing zero bits and count # of one bits */
303 root 1.1 #if ECB_GCC_VERSION(3,4)
304 root 1.49 /* we assume int == 32 bit, long == 32 or 64 bit and long long == 64 bit */
305     #define ecb_ld32(x) (__builtin_clz (x) ^ 31)
306     #define ecb_ld64(x) (__builtin_clzll (x) ^ 63)
307 root 1.35 #define ecb_ctz32(x) __builtin_ctz (x)
308 root 1.49 #define ecb_ctz64(x) __builtin_ctzll (x)
309 root 1.35 #define ecb_popcount32(x) __builtin_popcount (x)
310 root 1.49 /* no popcountll */
311 root 1.1 #else
312 root 1.39 ecb_function_ int ecb_ctz32 (uint32_t x) ecb_const;
313     ecb_function_ int
314 root 1.35 ecb_ctz32 (uint32_t x)
315     {
316     int r = 0;
317    
318 root 1.48 x &= ~x + 1; /* this isolates the lowest bit */
319 root 1.35
320 root 1.50 #if ECB_branchless_on_i386
321     r += !!(x & 0xaaaaaaaa) << 0;
322     r += !!(x & 0xcccccccc) << 1;
323     r += !!(x & 0xf0f0f0f0) << 2;
324     r += !!(x & 0xff00ff00) << 3;
325     r += !!(x & 0xffff0000) << 4;
326     #else
327 root 1.35 if (x & 0xaaaaaaaa) r += 1;
328     if (x & 0xcccccccc) r += 2;
329     if (x & 0xf0f0f0f0) r += 4;
330     if (x & 0xff00ff00) r += 8;
331     if (x & 0xffff0000) r += 16;
332 root 1.50 #endif
333 root 1.35
334     return r;
335     }
336    
337 root 1.49 ecb_function_ int ecb_ctz64 (uint64_t x) ecb_const;
338     ecb_function_ int
339     ecb_ctz64 (uint64_t x)
340     {
341     int shift = x & 0xffffffffU ? 0 : 32;
342 root 1.50 return ecb_ctz32 (x >> shift) + shift;
343 root 1.49 }
344    
345 root 1.39 ecb_function_ int ecb_popcount32 (uint32_t x) ecb_const;
346     ecb_function_ int
347 root 1.35 ecb_popcount32 (uint32_t x)
348     {
349     x -= (x >> 1) & 0x55555555;
350     x = ((x >> 2) & 0x33333333) + (x & 0x33333333);
351     x = ((x >> 4) + x) & 0x0f0f0f0f;
352     x *= 0x01010101;
353 root 1.1
354 root 1.35 return x >> 24;
355     }
356 root 1.49
357     ecb_function_ int ecb_ld32 (uint32_t x) ecb_const;
358     ecb_function_ int ecb_ld32 (uint32_t x)
359     {
360 root 1.50 int r = 0;
361 root 1.49
362 root 1.50 if (x >> 16) { x >>= 16; r += 16; }
363     if (x >> 8) { x >>= 8; r += 8; }
364     if (x >> 4) { x >>= 4; r += 4; }
365     if (x >> 2) { x >>= 2; r += 2; }
366     if (x >> 1) { r += 1; }
367 root 1.49
368     return r;
369     }
370    
371     ecb_function_ int ecb_ld64 (uint64_t x) ecb_const;
372     ecb_function_ int ecb_ld64 (uint64_t x)
373     {
374 root 1.50 int r = 0;
375 root 1.49
376 root 1.50 if (x >> 32) { x >>= 32; r += 32; }
377 root 1.49
378 root 1.50 return r + ecb_ld32 (x);
379 root 1.49 }
380 root 1.1 #endif
381    
382 root 1.88 ecb_function_ ecb_bool ecb_is_pot32 (uint32_t x) ecb_const;
383     ecb_function_ ecb_bool ecb_is_pot32 (uint32_t x) { return !(x & (x - 1)); }
384     ecb_function_ ecb_bool ecb_is_pot64 (uint64_t x) ecb_const;
385     ecb_function_ ecb_bool ecb_is_pot64 (uint64_t x) { return !(x & (x - 1)); }
386    
387 root 1.71 ecb_function_ uint8_t ecb_bitrev8 (uint8_t x) ecb_const;
388 root 1.70 ecb_function_ uint8_t ecb_bitrev8 (uint8_t x)
389     {
390     return ( (x * 0x0802U & 0x22110U)
391     | (x * 0x8020U & 0x88440U)) * 0x10101U >> 16;
392     }
393    
394 root 1.71 ecb_function_ uint16_t ecb_bitrev16 (uint16_t x) ecb_const;
395 root 1.70 ecb_function_ uint16_t ecb_bitrev16 (uint16_t x)
396     {
397     x = ((x >> 1) & 0x5555) | ((x & 0x5555) << 1);
398     x = ((x >> 2) & 0x3333) | ((x & 0x3333) << 2);
399     x = ((x >> 4) & 0x0f0f) | ((x & 0x0f0f) << 4);
400     x = ( x >> 8 ) | ( x << 8);
401    
402     return x;
403     }
404    
405 root 1.71 ecb_function_ uint32_t ecb_bitrev32 (uint32_t x) ecb_const;
406 root 1.70 ecb_function_ uint32_t ecb_bitrev32 (uint32_t x)
407     {
408     x = ((x >> 1) & 0x55555555) | ((x & 0x55555555) << 1);
409     x = ((x >> 2) & 0x33333333) | ((x & 0x33333333) << 2);
410     x = ((x >> 4) & 0x0f0f0f0f) | ((x & 0x0f0f0f0f) << 4);
411     x = ((x >> 8) & 0x00ff00ff) | ((x & 0x00ff00ff) << 8);
412     x = ( x >> 16 ) | ( x << 16);
413    
414     return x;
415     }
416    
417 root 1.49 /* popcount64 is only available on 64 bit cpus as gcc builtin */
418     /* so for this version we are lazy */
419     ecb_function_ int ecb_popcount64 (uint64_t x) ecb_const;
420     ecb_function_ int
421     ecb_popcount64 (uint64_t x)
422     {
423     return ecb_popcount32 (x) + ecb_popcount32 (x >> 32);
424     }
425    
426 root 1.50 ecb_inline uint8_t ecb_rotl8 (uint8_t x, unsigned int count) ecb_const;
427     ecb_inline uint8_t ecb_rotr8 (uint8_t x, unsigned int count) ecb_const;
428     ecb_inline uint16_t ecb_rotl16 (uint16_t x, unsigned int count) ecb_const;
429     ecb_inline uint16_t ecb_rotr16 (uint16_t x, unsigned int count) ecb_const;
430     ecb_inline uint32_t ecb_rotl32 (uint32_t x, unsigned int count) ecb_const;
431     ecb_inline uint32_t ecb_rotr32 (uint32_t x, unsigned int count) ecb_const;
432     ecb_inline uint64_t ecb_rotl64 (uint64_t x, unsigned int count) ecb_const;
433     ecb_inline uint64_t ecb_rotr64 (uint64_t x, unsigned int count) ecb_const;
434    
435     ecb_inline uint8_t ecb_rotl8 (uint8_t x, unsigned int count) { return (x >> ( 8 - count)) | (x << count); }
436     ecb_inline uint8_t ecb_rotr8 (uint8_t x, unsigned int count) { return (x << ( 8 - count)) | (x >> count); }
437     ecb_inline uint16_t ecb_rotl16 (uint16_t x, unsigned int count) { return (x >> (16 - count)) | (x << count); }
438     ecb_inline uint16_t ecb_rotr16 (uint16_t x, unsigned int count) { return (x << (16 - count)) | (x >> count); }
439     ecb_inline uint32_t ecb_rotl32 (uint32_t x, unsigned int count) { return (x >> (32 - count)) | (x << count); }
440     ecb_inline uint32_t ecb_rotr32 (uint32_t x, unsigned int count) { return (x << (32 - count)) | (x >> count); }
441     ecb_inline uint64_t ecb_rotl64 (uint64_t x, unsigned int count) { return (x >> (64 - count)) | (x << count); }
442     ecb_inline uint64_t ecb_rotr64 (uint64_t x, unsigned int count) { return (x << (64 - count)) | (x >> count); }
443    
444 root 1.13 #if ECB_GCC_VERSION(4,3)
445 root 1.49 #define ecb_bswap16(x) (__builtin_bswap32 (x) >> 16)
446     #define ecb_bswap32(x) __builtin_bswap32 (x)
447     #define ecb_bswap64(x) __builtin_bswap64 (x)
448 root 1.13 #else
449 root 1.50 ecb_function_ uint16_t ecb_bswap16 (uint16_t x) ecb_const;
450     ecb_function_ uint16_t
451     ecb_bswap16 (uint16_t x)
452 root 1.49 {
453 root 1.50 return ecb_rotl16 (x, 8);
454 root 1.49 }
455    
456 root 1.39 ecb_function_ uint32_t ecb_bswap32 (uint32_t x) ecb_const;
457     ecb_function_ uint32_t
458 root 1.35 ecb_bswap32 (uint32_t x)
459     {
460 root 1.50 return (((uint32_t)ecb_bswap16 (x)) << 16) | ecb_bswap16 (x >> 16);
461 root 1.35 }
462    
463 root 1.49 ecb_function_ uint64_t ecb_bswap64 (uint64_t x) ecb_const;
464     ecb_function_ uint64_t
465     ecb_bswap64 (uint64_t x)
466 root 1.35 {
467 root 1.50 return (((uint64_t)ecb_bswap32 (x)) << 32) | ecb_bswap32 (x >> 32);
468 root 1.35 }
469 root 1.13 #endif
470    
471     #if ECB_GCC_VERSION(4,5)
472 root 1.35 #define ecb_unreachable() __builtin_unreachable ()
473 root 1.13 #else
474 root 1.35 /* this seems to work fine, but gcc always emits a warning for it :/ */
475 root 1.75 ecb_inline void ecb_unreachable (void) ecb_noreturn;
476     ecb_inline void ecb_unreachable (void) { }
477 root 1.13 #endif
478    
479 root 1.41 /* try to tell the compiler that some condition is definitely true */
480 root 1.100 #define ecb_assume(cond) if (!(cond)) ecb_unreachable (); else 0
481 root 1.41
482 root 1.76 ecb_inline unsigned char ecb_byteorder_helper (void) ecb_const;
483     ecb_inline unsigned char
484 root 1.23 ecb_byteorder_helper (void)
485 root 1.3 {
486 root 1.98 /* the union code still generates code under pressure in gcc, */
487 sf-exg 1.111 /* but less than using pointers, and always seems to */
488 root 1.98 /* successfully return a constant. */
489     /* the reason why we have this horrible preprocessor mess */
490 root 1.99 /* is to avoid it in all cases, at least on common architectures */
491 sf-exg 1.111 /* or when using a recent enough gcc version (>= 4.6) */
492 root 1.98 #if __i386 || __i386__ || _M_X86 || __amd64 || __amd64__ || _M_X64
493     return 0x44;
494     #elif __BYTE_ORDER__ && __BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__
495     return 0x44;
496     #elif __BYTE_ORDER__ && __BYTE_ORDER__ == __ORDER_BIG_ENDIAN__
497     retrurn 0x11;
498     #else
499     union
500     {
501     uint32_t i;
502     uint8_t c;
503     } u = { 0x11223344 };
504     return u.c;
505     #endif
506 root 1.3 }
507    
508 root 1.76 ecb_inline ecb_bool ecb_big_endian (void) ecb_const;
509     ecb_inline ecb_bool ecb_big_endian (void) { return ecb_byteorder_helper () == 0x11; }
510     ecb_inline ecb_bool ecb_little_endian (void) ecb_const;
511     ecb_inline ecb_bool ecb_little_endian (void) { return ecb_byteorder_helper () == 0x44; }
512 root 1.3
513 root 1.39 #if ECB_GCC_VERSION(3,0) || ECB_C99
514 root 1.35 #define ecb_mod(m,n) ((m) % (n) + ((m) % (n) < 0 ? (n) : 0))
515 root 1.31 #else
516 root 1.35 #define ecb_mod(m,n) ((m) < 0 ? ((n) - 1 - ((-1 - (m)) % (n))) : ((m) % (n)))
517 root 1.31 #endif
518 root 1.21
519 sf-exg 1.68 #if __cplusplus
520     template<typename T>
521     static inline T ecb_div_rd (T val, T div)
522     {
523     return val < 0 ? - ((-val + div - 1) / div) : (val ) / div;
524     }
525     template<typename T>
526     static inline T ecb_div_ru (T val, T div)
527     {
528     return val < 0 ? - ((-val ) / div) : (val + div - 1) / div;
529     }
530     #else
531     #define ecb_div_rd(val,div) ((val) < 0 ? - ((-(val) + (div) - 1) / (div)) : ((val) ) / (div))
532     #define ecb_div_ru(val,div) ((val) < 0 ? - ((-(val) ) / (div)) : ((val) + (div) - 1) / (div))
533     #endif
534 sf-exg 1.67
535 root 1.5 #if ecb_cplusplus_does_not_suck
536 root 1.40 /* does not work for local types (http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2008/n2657.htm) */
537 root 1.35 template<typename T, int N>
538     static inline int ecb_array_length (const T (&arr)[N])
539     {
540     return N;
541     }
542 root 1.5 #else
543 root 1.35 #define ecb_array_length(name) (sizeof (name) / sizeof (name [0]))
544 root 1.5 #endif
545    
546 root 1.104 /*******************************************************************************/
547     /* floating point stuff, can be disabled by defining ECB_NO_LIBM */
548    
549     /* basically, everything uses "ieee pure-endian" floating point numbers */
550     /* the only noteworthy exception is ancient armle, which uses order 43218765 */
551     #if 0 \
552     || __i386 || __i386__ \
553     || __amd64 || __amd64__ || __x86_64 || __x86_64__ \
554     || __powerpc__ || __ppc__ || __powerpc64__ || __ppc64__ \
555     || defined __arm__ && defined __ARM_EABI__ \
556     || defined __s390__ || defined __s390x__ \
557     || defined __mips__ \
558     || defined __alpha__ \
559     || defined __hppa__ \
560     || defined __ia64__ \
561     || defined _M_IX86 || defined _M_AMD64 || defined _M_IA64
562     #define ECB_STDFP 1
563     #include <string.h> /* for memcpy */
564 root 1.102 #else
565 root 1.104 #define ECB_STDFP 0
566 root 1.109 #include <math.h> /* for frexp*, ldexp* */
567 root 1.102 #endif
568    
569 root 1.104 #ifndef ECB_NO_LIBM
570 root 1.103
571 root 1.104 /* convert a float to ieee single/binary32 */
572 root 1.103 ecb_function_ uint32_t ecb_float_to_binary32 (float x) ecb_const;
573     ecb_function_ uint32_t
574     ecb_float_to_binary32 (float x)
575     {
576     uint32_t r;
577    
578     #if ECB_STDFP
579 root 1.104 memcpy (&r, &x, 4);
580 root 1.103 #else
581 root 1.105 /* slow emulation, works for anything but -0 */
582 root 1.103 uint32_t m;
583     int e;
584    
585 root 1.108 if (x == 0e0f ) return 0x00000000U;
586 root 1.103 if (x > +3.40282346638528860e+38f) return 0x7f800000U;
587     if (x < -3.40282346638528860e+38f) return 0xff800000U;
588 root 1.105 if (x != x ) return 0x7fbfffffU;
589 root 1.103
590     m = frexpf (x, &e) * 0x1000000U;
591    
592     r = m & 0x80000000U;
593    
594     if (r)
595     m = -m;
596    
597 root 1.108 if (e <= -126)
598 root 1.103 {
599     m &= 0xffffffU;
600     m >>= (-125 - e);
601     e = -126;
602     }
603    
604     r |= (e + 126) << 23;
605     r |= m & 0x7fffffU;
606     #endif
607    
608     return r;
609     }
610    
611 root 1.104 /* converts an ieee single/binary32 to a float */
612 root 1.103 ecb_function_ float ecb_binary32_to_float (uint32_t x) ecb_const;
613     ecb_function_ float
614     ecb_binary32_to_float (uint32_t x)
615     {
616     float r;
617    
618     #if ECB_STDFP
619 root 1.104 memcpy (&r, &x, 4);
620 root 1.103 #else
621     /* emulation, only works for normals and subnormals and +0 */
622     int neg = x >> 31;
623     int e = (x >> 23) & 0xffU;
624    
625     x &= 0x7fffffU;
626    
627     if (e)
628     x |= 0x800000U;
629 root 1.104 else
630     e = 1;
631 root 1.103
632     /* we distrust ldexpf a bit and do the 2**-24 scaling by an extra multiply */
633 root 1.108 r = ldexpf (x * (0.5f / 0x800000U), e - 126);
634 root 1.103
635     r = neg ? -r : r;
636     #endif
637    
638     return r;
639     }
640    
641 root 1.104 /* convert a double to ieee double/binary64 */
642 root 1.103 ecb_function_ uint64_t ecb_double_to_binary64 (double x) ecb_const;
643     ecb_function_ uint64_t
644     ecb_double_to_binary64 (double x)
645     {
646 root 1.104 uint64_t r;
647    
648     #if ECB_STDFP
649     memcpy (&r, &x, 8);
650     #else
651 root 1.105 /* slow emulation, works for anything but -0 */
652 root 1.104 uint64_t m;
653     int e;
654    
655 root 1.108 if (x == 0e0 ) return 0x0000000000000000U;
656 root 1.104 if (x > +1.79769313486231470e+308) return 0x7ff0000000000000U;
657     if (x < -1.79769313486231470e+308) return 0xfff0000000000000U;
658 root 1.105 if (x != x ) return 0X7ff7ffffffffffffU;
659 root 1.104
660     m = frexp (x, &e) * 0x20000000000000U;
661    
662     r = m & 0x8000000000000000;;
663    
664     if (r)
665     m = -m;
666    
667 root 1.108 if (e <= -1022)
668 root 1.104 {
669     m &= 0x1fffffffffffffU;
670     m >>= (-1021 - e);
671     e = -1022;
672     }
673    
674     r |= ((uint64_t)(e + 1022)) << 52;
675     r |= m & 0xfffffffffffffU;
676     #endif
677    
678     return r;
679     }
680    
681     /* converts an ieee double/binary64 to a double */
682     ecb_function_ double ecb_binary64_to_double (uint64_t x) ecb_const;
683     ecb_function_ double
684     ecb_binary64_to_double (uint64_t x)
685     {
686     double r;
687    
688     #if ECB_STDFP
689     memcpy (&r, &x, 8);
690     #else
691     /* emulation, only works for normals and subnormals and +0 */
692     int neg = x >> 63;
693     int e = (x >> 52) & 0x7ffU;
694    
695     x &= 0xfffffffffffffU;
696    
697     if (e)
698     x |= 0x10000000000000U;
699     else
700     e = 1;
701    
702 root 1.107 /* we distrust ldexp a bit and do the 2**-53 scaling by an extra multiply */
703 root 1.108 r = ldexp (x * (0.5 / 0x10000000000000U), e - 1022);
704 root 1.104
705     r = neg ? -r : r;
706     #endif
707    
708     return r;
709 root 1.103 }
710    
711     #endif
712 root 1.102
713 root 1.1 #endif
714