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Re: bitmap.c tweeks


On Fri, Jul 06, 2001 at 10:58:31PM -0400, Daniel Berlin wrote:
> We could also just use a lookup table for the 8 bits or less cases,
> using a table of the number of leading zeroes.
[...]
> Hard to say whether it would be faster than the last part of the
> binary search in reality, however.

Depends on the hardware.  E.g. the memory reference
will be slower on an alpha.

Fastest is to know that a bit search instruction 
exists.  I didn't feel like playing with longlong.h
which has that knowledge.


r~


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