(svn r11378) -Codechange: optimize KillFirstBit2x64 (skidd13)

This commit is contained in:
truelight 2007-11-04 18:28:52 +00:00
parent 525d239bc2
commit 038817a708

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@ -416,21 +416,14 @@ Faster ( or at least cleaner ) implementation below?
* Clear the first bit in an integer.
*
* This function returns a value where the first bit (from LSB)
* is cleared. This function checks, similar to FindFirstBit2x64,
* the bits at 0x3F3F.
* is cleared. This function checks only the bits of 0x3F3F!
*
* @param value The value to clear the first bit
* @return The new value with the first bit cleared
* @see KILL_FIRST_BIT
* @see FindFirstBit2x64
*/
static inline int KillFirstBit2x64(int value)
{
if (GB(value, 0, 8) == 0) {
return KILL_FIRST_BIT(GB(value, 8, 6)) << 8;
} else {
return value & (KILL_FIRST_BIT(GB(value, 0, 6)) | 0x3F00);
}
return value &= (int)(value - 1) | 0x3FFFC0C0;
}
/**