diff options
| author | click <none@none> | 2010-08-07 19:01:57 +0200 |
|---|---|---|
| committer | click <none@none> | 2010-08-07 19:01:57 +0200 |
| commit | ce435f6d4f84462c0707bbc608d767648d5e99c3 (patch) | |
| tree | dabac44fd559c925acf2171adb0ae3038f05ad7b /externals/mysql/my_bit.h | |
| parent | 3cc24e0971f96b9ffa4032a154750e4224ea499d (diff) | |
BuildSystem/VS: Remove now defunct an unmaintained buildfiles - use CMake for generating solutionfiles
--HG--
branch : trunk
Diffstat (limited to 'externals/mysql/my_bit.h')
| -rw-r--r-- | externals/mysql/my_bit.h | 109 |
1 files changed, 0 insertions, 109 deletions
diff --git a/externals/mysql/my_bit.h b/externals/mysql/my_bit.h deleted file mode 100644 index 2e464e89049..00000000000 --- a/externals/mysql/my_bit.h +++ /dev/null @@ -1,109 +0,0 @@ -/* - Some useful bit functions -*/ - -C_MODE_START -#ifdef HAVE_INLINE - -extern const char _my_bits_nbits[256]; -extern const uchar _my_bits_reverse_table[256]; - -/* - Find smallest X in 2^X >= value - This can be used to divide a number with value by doing a shift instead -*/ - -STATIC_INLINE uint my_bit_log2(ulong value) -{ - uint bit; - for (bit=0 ; value > 1 ; value>>=1, bit++) ; - return bit; -} - -STATIC_INLINE uint my_count_bits(ulonglong v) -{ -#if SIZEOF_LONG_LONG > 4 - /* The following code is a bit faster on 16 bit machines than if we would - only shift v */ - ulong v2=(ulong) (v >> 32); - return (uint) (uchar) (_my_bits_nbits[(uchar) v] + - _my_bits_nbits[(uchar) (v >> 8)] + - _my_bits_nbits[(uchar) (v >> 16)] + - _my_bits_nbits[(uchar) (v >> 24)] + - _my_bits_nbits[(uchar) (v2)] + - _my_bits_nbits[(uchar) (v2 >> 8)] + - _my_bits_nbits[(uchar) (v2 >> 16)] + - _my_bits_nbits[(uchar) (v2 >> 24)]); -#else - return (uint) (uchar) (_my_bits_nbits[(uchar) v] + - _my_bits_nbits[(uchar) (v >> 8)] + - _my_bits_nbits[(uchar) (v >> 16)] + - _my_bits_nbits[(uchar) (v >> 24)]); -#endif -} - -STATIC_INLINE uint my_count_bits_ushort(ushort v) -{ - return _my_bits_nbits[v]; -} - - -/* - Next highest power of two - - SYNOPSIS - my_round_up_to_next_power() - v Value to check - - RETURN - Next or equal power of 2 - Note: 0 will return 0 - - NOTES - Algorithm by Sean Anderson, according to: - http://graphics.stanford.edu/~seander/bithacks.html - (Orignal code public domain) - - Comments shows how this works with 01100000000000000000000000001011 -*/ - -STATIC_INLINE uint32 my_round_up_to_next_power(uint32 v) -{ - v--; /* 01100000000000000000000000001010 */ - v|= v >> 1; /* 01110000000000000000000000001111 */ - v|= v >> 2; /* 01111100000000000000000000001111 */ - v|= v >> 4; /* 01111111110000000000000000001111 */ - v|= v >> 8; /* 01111111111111111100000000001111 */ - v|= v >> 16; /* 01111111111111111111111111111111 */ - return v+1; /* 10000000000000000000000000000000 */ -} - -STATIC_INLINE uint32 my_clear_highest_bit(uint32 v) -{ - uint32 w=v >> 1; - w|= w >> 1; - w|= w >> 2; - w|= w >> 4; - w|= w >> 8; - w|= w >> 16; - return v & w; -} - -STATIC_INLINE uint32 my_reverse_bits(uint32 key) -{ - return - (_my_bits_reverse_table[ key & 255] << 24) | - (_my_bits_reverse_table[(key>> 8) & 255] << 16) | - (_my_bits_reverse_table[(key>>16) & 255] << 8) | - _my_bits_reverse_table[(key>>24) ]; -} - -#else /* HAVE_INLINE */ -extern uint my_bit_log2(ulong value); -extern uint32 my_round_up_to_next_power(uint32 v); -uint32 my_clear_highest_bit(uint32 v); -uint32 my_reverse_bits(uint32 key); -extern uint my_count_bits(ulonglong v); -extern uint my_count_bits_ushort(ushort v); -#endif /* HAVE_INLINE */ -C_MODE_END |
