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Revision: 1.23
Committed: Thu May 26 19:40:09 2011 UTC (13 years ago) by root
Content type: text/plain
Branch: MAIN
Changes since 1.22: +6 -6 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 1.2 * Copyright (©) 2009-2011 Marc Alexander Lehmann
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 1.6 #include <inttypes.h>
34    
35 root 1.12 /* many compilers define _GNUC_ to some versions but then only implement
36     * what their idiot authors think are the "more important" extensions,
37 root 1.18 * causing enourmous grief in return for some better fake benchmark numbers.
38     * or so.
39 root 1.12 * we try to detect these and simply assume they are not gcc - if they have
40     * an issue with that they should have done it right in the first place.
41     */
42 root 1.14 #ifndef ECB_GCC_VERSION
43     # if defined(__INTEL_COMPILER) || defined(__SUNPRO_C) || defined(__llvm__)
44     # define ECB_GCC_VERSION(major,minor) 0
45     # else
46     # define ECB_GCC_VERSION(major,minor) (__GNUC__ > (major) || (__GNUC__ == (major) && __GNUC_MINOR__ >= (minor)))
47     # endif
48 root 1.12 #endif
49 root 1.1
50 root 1.4 #ifndef __cplusplus
51     # if __STDC_VERSION__ >= 199901L
52     # define ECB_INLINE inline
53     typedef _Bool ecb_bool;
54     # else
55     # define ECB_INLINE inline /* yeah! */
56     typedef int ecb_bool;
57     # endif
58     #endif
59    
60 root 1.8 #define ECB_CONCAT_(a, b) a ## b
61     #define ECB_CONCAT(a, b) ECB_CONCAT_(a, b)
62     #define ECB_STRINGIFY_(a) # a
63     #define ECB_STRINGIFY(a) ECB_STRINGIFY_(a)
64    
65 root 1.4 #define ECB_HEADER_INLINE static ECB_INLINE
66 root 1.3
67 root 1.1 #if ECB_GCC_VERSION(3,1)
68     # define ecb_attribute(attrlist) __attribute__(attrlist)
69 root 1.22 # define ecb_is_constant(expr) __builtin_constant_p (expr)
70 root 1.1 # define ecb_expect(expr,value) __builtin_expect ((expr),(value))
71     # define ecb_prefetch(addr,rw,locality) __builtin_prefetch (addr, rw, locality)
72     #else
73     # define ecb_attribute(attrlist)
74 root 1.22 # define ecb_is_constant(expr) 0
75 root 1.1 # define ecb_expect(expr,value) (expr)
76     # define ecb_prefetch(addr,rw,locality)
77     #endif
78    
79 root 1.2 /* no emulation for ecb_decltype */
80 root 1.1 #if ECB_GCC_VERSION(4,5)
81     # define ecb_decltype(x) __decltype(x)
82     #elif ECB_GCC_VERSION(3,0)
83     # define ecb_decltype(x) typeof(x)
84     #endif
85    
86     #define ecb_noinline ecb_attribute ((noinline))
87     #define ecb_noreturn ecb_attribute ((noreturn))
88     #define ecb_unused ecb_attribute ((unused))
89     #define ecb_const ecb_attribute ((const))
90     #define ecb_pure ecb_attribute ((pure))
91 root 1.4 #define ecb_hot ecb_attribute ((hot)) /* 4.3 */
92     #define ecb_cold ecb_attribute ((cold)) /* 4.3 */
93 root 1.1
94 root 1.22 /* put into if's if you are very sure that the expression */
95 root 1.3 /* is mostly true or mosty false. note that these return */
96     /* booleans, not the expression. */
97 root 1.11 #define ecb_unlikely(expr) ecb_expect (!!(expr), 0)
98     #define ecb_likely(expr) ecb_expect (!!(expr), 1)
99 root 1.1
100 root 1.3 /* try to tell the compiler that some condition is definitely true */
101 root 1.19 #define ecb_assume(cond) do { if (!(cond)) ecb_unreachable (); } while (0)
102 root 1.1
103 root 1.3 /* count trailing zero bits and count # of one bits */
104 root 1.1 #if ECB_GCC_VERSION(3,4)
105 root 1.16 #define ecb_ctz32 (x) __builtin_ctz (x)
106     #define ecb_popcount32 (x) __builtin_popcount (x)
107 root 1.1 #else
108 root 1.19 ECB_HEADER_INLINE int ecb_ctz32 (uint32_t x) ecb_const;
109 root 1.3 ECB_HEADER_INLINE
110 root 1.14 ecb_ctz32 (uint32_t x)
111 root 1.1 {
112     int r = 0;
113    
114 root 1.4 x &= -x; /* this isolates the lowest bit */
115 root 1.1
116     if (x & 0xaaaaaaaa) r += 1;
117     if (x & 0xcccccccc) r += 2;
118     if (x & 0xf0f0f0f0) r += 4;
119     if (x & 0xff00ff00) r += 8;
120     if (x & 0xffff0000) r += 16;
121    
122     return r;
123     }
124    
125 root 1.16 ECB_HEADER_INLINE int ecb_popcount32 (uint32_t x) ecb_const;
126 root 1.3 ECB_HEADER_INLINE
127 root 1.14 ecb_popcount32 (uint32_t x)
128 root 1.1 {
129     x -= (x >> 1) & 0x55555555;
130     x = ((x >> 2) & 0x33333333) + (x & 0x33333333);
131     x = ((x >> 4) + x) & 0x0f0f0f0f;
132     x *= 0x01010101;
133    
134     return x >> 24;
135     }
136     #endif
137    
138 root 1.13 #if ECB_GCC_VERSION(4,3)
139 root 1.16 # define ecb_bswap32(x) __builtin_bswap32 (x)
140 root 1.20 # define ecb_bswap16(x) (__builtin_bswap32(x) >> 16)
141 root 1.13 #else
142 root 1.16 ECB_HEADER_INLINE uint32_t ecb_bswap32 (uint32_t x) ecb_const;
143 root 1.14 ECB_HEADER_INLINE uint32_t
144 root 1.13 ecb_bswap32 (uint32_t x)
145     {
146     return (x >> 24)
147     | ((x >> 8) & 0x0000ff00)
148     | ((x << 8) & 0x00ff0000)
149     | (x << 24);
150     }
151 root 1.20
152     ECB_HEADER_INLINE uint32_t ecb_bswap16 (uint32_t x) ecb_const;
153     ECB_HEADER_INLINE uint32_t
154     ecb_bswap16 (uint32_t x)
155     {
156     return ((x >> 8) & 0xff)
157     | ((x << 8) & 0x00ff0000)
158     | (x << 24);
159     }
160 root 1.13 #endif
161    
162     #if ECB_GCC_VERSION(4,5)
163 root 1.16 # define ecb_unreachable() __builtin_unreachable ()
164 root 1.13 #else
165     /* this seems to work fine, but gcc always emits a warning for it :/ */
166 root 1.17 ECB_HEADER_INLINE void ecb_unreachable (void) ecb_noreturn;
167 root 1.14 ECB_HEADER_INLINE void ecb_unreachable (void) { }
168 root 1.13 #endif
169    
170 root 1.23 ECB_HEADER_INLINE unsigned char ecb_byteorder_helper (void) ecb_const;
171 root 1.3 ECB_HEADER_INLINE unsigned char
172 root 1.23 ecb_byteorder_helper (void)
173 root 1.3 {
174     const uint32_t u = 0x11223344;
175     return *(unsigned char *)&u;
176     }
177    
178 root 1.23 ECB_HEADER_INLINE ecb_bool ecb_big_endian (void) ecb_const;
179     ECB_HEADER_INLINE ecb_bool ecb_big_endian (void) { return ecb_byteorder_helper () == 0x11; };
180     ECB_HEADER_INLINE ecb_bool ecb_little_endian (void) ecb_const;
181     ECB_HEADER_INLINE ecb_bool ecb_little_endian (void) { return ecb_byteorder_helper () == 0x44; };
182 root 1.3
183 root 1.21 #define ecb_mod(m, n) ((m) < 0 ? ((n) - (-(m) % (n))) : ((m) % (n)))
184    
185 root 1.5 #if ecb_cplusplus_does_not_suck
186     // does not work for local types (http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2008/n2657.htm)
187     template<typename T, int N>
188 root 1.8 static inline int ecb_array_length (const T (&arr)[N])
189 root 1.5 {
190     return N;
191     }
192     #else
193     #define ecb_array_length(name) (sizeof (name) / sizeof (name [0]))
194     #endif
195    
196 root 1.14 ECB_INLINE uint32_t ecb_rotr32 (uint32_t x, unsigned int count) ecb_const;
197 root 1.6 ECB_INLINE uint32_t
198 root 1.9 ecb_rotr32 (uint32_t x, unsigned int count)
199 root 1.6 {
200 root 1.9 return (x << (32 - count)) | (x >> count);
201 root 1.6 }
202    
203 root 1.14 ECB_INLINE uint32_t ecb_rotl32 (uint32_t x, unsigned int count) ecb_const;
204 root 1.6 ECB_INLINE uint32_t
205 root 1.9 ecb_rotl32 (uint32_t x, unsigned int count)
206 root 1.6 {
207 root 1.9 return (x >> (32 - count)) | (x << count);
208 root 1.6 }
209    
210 root 1.1 #endif
211