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authormonty@mysql.com/narttu.mysql.fi <>2007-10-11 18:07:40 +0300
committermonty@mysql.com/narttu.mysql.fi <>2007-10-11 18:07:40 +0300
commit7887babe69412b6f33f6cb782f468e9b58695fb9 (patch)
tree2f3bb6c8948945094ff740b1991e2d9b80a55ec3 /mysys/my_bit.c
parent9473b90fd5c16a2043b70d869721e80b1d9916f7 (diff)
downloadmariadb-git-7887babe69412b6f33f6cb782f468e9b58695fb9.tar.gz
Moved a lot of old bug fixes and safe cleanups from Maria 5.1 tree to 5.1
- Reserver namespace and place in frm for TABLE_CHECKSUM and PAGE_CHECKSUM create options - Added syncing of directory when creating .frm files - Portability fixes - Added missing cast that could cause bugs - Code cleanups - Made some bit functions inline - Moved things out of myisam.h to my_handler.h to make them more accessable - Renamed some myisam variables and defines to make them more globaly usable (as they are used outside of MyISAM) - Fixed bugs in error conditions - Use compiler time asserts instead of run time - Fixed indentation HA_EXTRA_PREPARE_FOR_DELETE -> HA_EXTRA_PREPARE_FOR_DROP as the old name was wrong (Added a define for old value to ensure we don't break any old code) Added HA_EXTRA_PREPARE_FOR_RENAME as a signal for rename (before we used a DROP signal which is wrong) - Initialize error messages early to get better errors when mysqld or an engine fails to start - Fix windows bug that query_performance_frequency was not initialized if registry code failed - thread_stack -> my_thread_stack_size
Diffstat (limited to 'mysys/my_bit.c')
-rw-r--r--mysys/my_bit.c100
1 files changed, 32 insertions, 68 deletions
diff --git a/mysys/my_bit.c b/mysys/my_bit.c
index 5a9b1187c83..2881eb1ebd2 100644
--- a/mysys/my_bit.c
+++ b/mysys/my_bit.c
@@ -13,23 +13,18 @@
along with this program; if not, write to the Free Software
Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA */
-/* Some useful bit functions */
+#include <my_global.h>
-#include "mysys_priv.h"
-
-/*
- Find smallest X in 2^X >= value
- This can be used to divide a number with value by doing a shift instead
-*/
+#ifndef HAVE_INLINE
+/* the following will cause all inline functions to be instantiated */
+#define HAVE_INLINE
+#undef STATIC_INLINE
+#define STATIC_INLINE extern
+#endif
-uint my_bit_log2(ulong value)
-{
- uint bit;
- for (bit=0 ; value > 1 ; value>>=1, bit++) ;
- return bit;
-}
+#include <my_bit.h>
-static char nbits[256] = {
+const char _my_bits_nbits[256] = {
0, 1, 1, 2, 1, 2, 2, 3, 1, 2, 2, 3, 2, 3, 3, 4,
1, 2, 2, 3, 2, 3, 3, 4, 2, 3, 3, 4, 3, 4, 4, 5,
1, 2, 2, 3, 2, 3, 3, 4, 2, 3, 3, 4, 3, 4, 4, 5,
@@ -48,60 +43,29 @@ static char nbits[256] = {
4, 5, 5, 6, 5, 6, 6, 7, 5, 6, 6, 7, 6, 7, 7, 8,
};
-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) (nbits[(uchar) v] +
- nbits[(uchar) (v >> 8)] +
- nbits[(uchar) (v >> 16)] +
- nbits[(uchar) (v >> 24)] +
- nbits[(uchar) (v2)] +
- nbits[(uchar) (v2 >> 8)] +
- nbits[(uchar) (v2 >> 16)] +
- nbits[(uchar) (v2 >> 24)]);
-#else
- return (uint) (uchar) (nbits[(uchar) v] +
- nbits[(uchar) (v >> 8)] +
- nbits[(uchar) (v >> 16)] +
- nbits[(uchar) (v >> 24)]);
-#endif
-}
-
-uint my_count_bits_ushort(ushort v)
-{
- return 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
+ perl -e 'print map{", 0x".unpack H2,pack B8,unpack b8,chr$_}(0..255)'
*/
+const uchar _my_bits_reverse_table[256]={
+0x00, 0x80, 0x40, 0xC0, 0x20, 0xA0, 0x60, 0xE0, 0x10, 0x90, 0x50, 0xD0, 0x30,
+0xB0, 0x70, 0xF0, 0x08, 0x88, 0x48, 0xC8, 0x28, 0xA8, 0x68, 0xE8, 0x18, 0x98,
+0x58, 0xD8, 0x38, 0xB8, 0x78, 0xF8, 0x04, 0x84, 0x44, 0xC4, 0x24, 0xA4, 0x64,
+0xE4, 0x14, 0x94, 0x54, 0xD4, 0x34, 0xB4, 0x74, 0xF4, 0x0C, 0x8C, 0x4C, 0xCC,
+0x2C, 0xAC, 0x6C, 0xEC, 0x1C, 0x9C, 0x5C, 0xDC, 0x3C, 0xBC, 0x7C, 0xFC, 0x02,
+0x82, 0x42, 0xC2, 0x22, 0xA2, 0x62, 0xE2, 0x12, 0x92, 0x52, 0xD2, 0x32, 0xB2,
+0x72, 0xF2, 0x0A, 0x8A, 0x4A, 0xCA, 0x2A, 0xAA, 0x6A, 0xEA, 0x1A, 0x9A, 0x5A,
+0xDA, 0x3A, 0xBA, 0x7A, 0xFA, 0x06, 0x86, 0x46, 0xC6, 0x26, 0xA6, 0x66, 0xE6,
+0x16, 0x96, 0x56, 0xD6, 0x36, 0xB6, 0x76, 0xF6, 0x0E, 0x8E, 0x4E, 0xCE, 0x2E,
+0xAE, 0x6E, 0xEE, 0x1E, 0x9E, 0x5E, 0xDE, 0x3E, 0xBE, 0x7E, 0xFE, 0x01, 0x81,
+0x41, 0xC1, 0x21, 0xA1, 0x61, 0xE1, 0x11, 0x91, 0x51, 0xD1, 0x31, 0xB1, 0x71,
+0xF1, 0x09, 0x89, 0x49, 0xC9, 0x29, 0xA9, 0x69, 0xE9, 0x19, 0x99, 0x59, 0xD9,
+0x39, 0xB9, 0x79, 0xF9, 0x05, 0x85, 0x45, 0xC5, 0x25, 0xA5, 0x65, 0xE5, 0x15,
+0x95, 0x55, 0xD5, 0x35, 0xB5, 0x75, 0xF5, 0x0D, 0x8D, 0x4D, 0xCD, 0x2D, 0xAD,
+0x6D, 0xED, 0x1D, 0x9D, 0x5D, 0xDD, 0x3D, 0xBD, 0x7D, 0xFD, 0x03, 0x83, 0x43,
+0xC3, 0x23, 0xA3, 0x63, 0xE3, 0x13, 0x93, 0x53, 0xD3, 0x33, 0xB3, 0x73, 0xF3,
+0x0B, 0x8B, 0x4B, 0xCB, 0x2B, 0xAB, 0x6B, 0xEB, 0x1B, 0x9B, 0x5B, 0xDB, 0x3B,
+0xBB, 0x7B, 0xFB, 0x07, 0x87, 0x47, 0xC7, 0x27, 0xA7, 0x67, 0xE7, 0x17, 0x97,
+0x57, 0xD7, 0x37, 0xB7, 0x77, 0xF7, 0x0F, 0x8F, 0x4F, 0xCF, 0x2F, 0xAF, 0x6F,
+0xEF, 0x1F, 0x9F, 0x5F, 0xDF, 0x3F, 0xBF, 0x7F, 0xFF
+};
-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 */
-}