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Comparing libecb/ecb.h (file contents):
Revision 1.14 by root, Thu May 26 18:26:59 2011 UTC vs.
Revision 1.16 by root, Thu May 26 18:34:23 2011 UTC

… …
98 98
99/* try to tell the compiler that some condition is definitely true */ 99/* try to tell the compiler that some condition is definitely true */
100#define ecb_assume(cond) do { if (!(cond)) unreachable (); } while (0) 100#define ecb_assume(cond) do { if (!(cond)) unreachable (); } while (0)
101 101
102/* count trailing zero bits and count # of one bits */ 102/* count trailing zero bits and count # of one bits */
103#if ECB_GCC_VERSION(3,4)
104#define ecb_ctz32 (x) __builtin_ctz (x)
105#define ecb_popcount32 (x) __builtin_popcount (x)
106#else
103ECB_HEADER_INLINE int ecb_ctz32 (uint32_t x) ecb_const; 107ECB_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 108ECB_HEADER_INLINE
110ecb_ctz32 (uint32_t x) 109ecb_ctz32 (uint32_t x)
111{ 110{
112 int r = 0; 111 int r = 0;
113 112
… …
120 if (x & 0xffff0000) r += 16; 119 if (x & 0xffff0000) r += 16;
121 120
122 return r; 121 return r;
123} 122}
124 123
124ECB_HEADER_INLINE int ecb_popcount32 (uint32_t x) ecb_const;
125ECB_HEADER_INLINE 125ECB_HEADER_INLINE
126ecb_popcount32 (uint32_t x) 126ecb_popcount32 (uint32_t x)
127{ 127{
128 x -= (x >> 1) & 0x55555555; 128 x -= (x >> 1) & 0x55555555;
129 x = ((x >> 2) & 0x33333333) + (x & 0x33333333); 129 x = ((x >> 2) & 0x33333333) + (x & 0x33333333);
… …
132 132
133 return x >> 24; 133 return x >> 24;
134} 134}
135#endif 135#endif
136 136
137#if ECB_GCC_VERSION(4,3)
138# define ecb_bswap32(x) __builtin_bswap32 (x)
139#else
137ECB_HEADER_INLINE uint32_t ecb_bswap32 (uint32_t x) ecb_const; 140ECB_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 141ECB_HEADER_INLINE uint32_t
142ecb_bswap32 (uint32_t x) 142ecb_bswap32 (uint32_t x)
143{ 143{
144 return (x >> 24) 144 return (x >> 24)
145 | ((x >> 8) & 0x0000ff00) 145 | ((x >> 8) & 0x0000ff00)
146 | ((x << 8) & 0x00ff0000) 146 | ((x << 8) & 0x00ff0000)
147 | (x << 24); 147 | (x << 24);
148} 148}
149#endif 149#endif
150 150
151ECB_HEADER_INLINE void ecb_unreachable (void) ecb_attribute ((noreturn));
152#if ECB_GCC_VERSION(4,5) 151#if ECB_GCC_VERSION(4,5)
153ECB_HEADER_INLINE void ecb_unreachable (void) { __builtin_unreachable (); } 152# define ecb_unreachable() __builtin_unreachable ()
154#else 153#else
155/* this seems to work fine, but gcc always emits a warning for it :/ */ 154/* this seems to work fine, but gcc always emits a warning for it :/ */
155ECB_HEADER_INLINE void ecb_unreachable (void) ecb_attribute ((noreturn));
156ECB_HEADER_INLINE void ecb_unreachable (void) { } 156ECB_HEADER_INLINE void ecb_unreachable (void) { }
157#endif 157#endif
158 158
159ECB_HEADER_INLINE unsigned char ecb_byteorder_helper () ecb_const; 159ECB_HEADER_INLINE unsigned char ecb_byteorder_helper () ecb_const;
160
161ECB_HEADER_INLINE unsigned char 160ECB_HEADER_INLINE unsigned char
162ecb_byteorder_helper () 161ecb_byteorder_helper ()
163{ 162{
164 const uint32_t u = 0x11223344; 163 const uint32_t u = 0x11223344;
165 return *(unsigned char *)&u; 164 return *(unsigned char *)&u;

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