ViewVC Help
View File | Revision Log | Show Annotations | Download File
/cvs/libecb/ecb.h
(Generate patch)

Comparing libecb/ecb.h (file contents):
Revision 1.14 by root, Thu May 26 18:26:59 2011 UTC vs.
Revision 1.18 by root, Thu May 26 18:36:43 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
5 * Copyright (©) 2011 Emanuele Giaquinta 5 * Copyright (©) 2011 Emanuele Giaquinta
6 * All rights reserved. 6 * All rights reserved.
7 * 7 *
… …
32 32
33#include <inttypes.h> 33#include <inttypes.h>
34 34
35/* many compilers define _GNUC_ to some versions but then only implement 35/* many compilers define _GNUC_ to some versions but then only implement
36 * what their idiot authors think are the "more important" extensions, 36 * what their idiot authors think are the "more important" extensions,
37 * causing enourmous grief for some better fake benchmark numbers or so. 37 * causing enourmous grief in return for some better fake benchmark numbers.
38 * or so.
38 * we try to detect these and simply assume they are not gcc - if they have 39 * we try to detect these and simply assume they are not gcc - if they have
39 * an issue with that they should have done it right in the first place. 40 * an issue with that they should have done it right in the first place.
40 */ 41 */
41#ifndef ECB_GCC_VERSION 42#ifndef ECB_GCC_VERSION
42# if defined(__INTEL_COMPILER) || defined(__SUNPRO_C) || defined(__llvm__) 43# if defined(__INTEL_COMPILER) || defined(__SUNPRO_C) || defined(__llvm__)
… …
98 99
99/* try to tell the compiler that some condition is definitely true */ 100/* try to tell the compiler that some condition is definitely true */
100#define ecb_assume(cond) do { if (!(cond)) unreachable (); } while (0) 101#define ecb_assume(cond) do { if (!(cond)) unreachable (); } while (0)
101 102
102/* count trailing zero bits and count # of one bits */ 103/* count trailing zero bits and count # of one bits */
104#if ECB_GCC_VERSION(3,4)
105#define ecb_ctz32 (x) __builtin_ctz (x)
106#define ecb_popcount32 (x) __builtin_popcount (x)
107#else
103ECB_HEADER_INLINE int ecb_ctz32 (uint32_t x) ecb_const; 108ECB_HEADER_INLINE int ecb_ctz32 (uint32_t x) ecb_const;
104ECB_HEADER_INLINE int ecb_popcount32 (uint32_t x) ecb_const;
105#if ECB_GCC_VERSION(3,4)
106ECB_HEADER_INLINE int ecb_ctz32 (uint32_t x) { return __builtin_ctz (x); }
107ECB_HEADER_INLINE int ecb_popcount32 (uint32_t x) { return __builtin_popcount (x); }
108#else
109ECB_HEADER_INLINE 109ECB_HEADER_INLINE
110ecb_ctz32 (uint32_t x) 110ecb_ctz32 (uint32_t x)
111{ 111{
112 int r = 0; 112 int r = 0;
113 113
… …
120 if (x & 0xffff0000) r += 16; 120 if (x & 0xffff0000) r += 16;
121 121
122 return r; 122 return r;
123} 123}
124 124
125ECB_HEADER_INLINE int ecb_popcount32 (uint32_t x) ecb_const;
125ECB_HEADER_INLINE 126ECB_HEADER_INLINE
126ecb_popcount32 (uint32_t x) 127ecb_popcount32 (uint32_t x)
127{ 128{
128 x -= (x >> 1) & 0x55555555; 129 x -= (x >> 1) & 0x55555555;
129 x = ((x >> 2) & 0x33333333) + (x & 0x33333333); 130 x = ((x >> 2) & 0x33333333) + (x & 0x33333333);
… …
132 133
133 return x >> 24; 134 return x >> 24;
134} 135}
135#endif 136#endif
136 137
138#if ECB_GCC_VERSION(4,3)
139# define ecb_bswap32(x) __builtin_bswap32 (x)
140#else
137ECB_HEADER_INLINE uint32_t ecb_bswap32 (uint32_t x) ecb_const; 141ECB_HEADER_INLINE uint32_t ecb_bswap32 (uint32_t x) ecb_const;
138#if ECB_GCC_VERSION(4,3)
139ECB_HEADER_INLINE uint32_t ecb_bswap32 (uint32_t x) { return __builtin_bswap32 (x); }
140#else
141ECB_HEADER_INLINE uint32_t 142ECB_HEADER_INLINE uint32_t
142ecb_bswap32 (uint32_t x) 143ecb_bswap32 (uint32_t x)
143{ 144{
144 return (x >> 24) 145 return (x >> 24)
145 | ((x >> 8) & 0x0000ff00) 146 | ((x >> 8) & 0x0000ff00)
146 | ((x << 8) & 0x00ff0000) 147 | ((x << 8) & 0x00ff0000)
147 | (x << 24); 148 | (x << 24);
148} 149}
149#endif 150#endif
150 151
151ECB_HEADER_INLINE void ecb_unreachable (void) ecb_attribute ((noreturn));
152#if ECB_GCC_VERSION(4,5) 152#if ECB_GCC_VERSION(4,5)
153ECB_HEADER_INLINE void ecb_unreachable (void) { __builtin_unreachable (); } 153# define ecb_unreachable() __builtin_unreachable ()
154#else 154#else
155/* this seems to work fine, but gcc always emits a warning for it :/ */ 155/* this seems to work fine, but gcc always emits a warning for it :/ */
156ECB_HEADER_INLINE void ecb_unreachable (void) ecb_noreturn;
156ECB_HEADER_INLINE void ecb_unreachable (void) { } 157ECB_HEADER_INLINE void ecb_unreachable (void) { }
157#endif 158#endif
158 159
159ECB_HEADER_INLINE unsigned char ecb_byteorder_helper () ecb_const; 160ECB_HEADER_INLINE unsigned char ecb_byteorder_helper () ecb_const;
160
161ECB_HEADER_INLINE unsigned char 161ECB_HEADER_INLINE unsigned char
162ecb_byteorder_helper () 162ecb_byteorder_helper ()
163{ 163{
164 const uint32_t u = 0x11223344; 164 const uint32_t u = 0x11223344;
165 return *(unsigned char *)&u; 165 return *(unsigned char *)&u;

Diff Legend

– Removed lines
+ Added lines
< Changed lines
> Changed lines