On Thu, Mar 30, 2000 at 02:46:37PM -0500, Richard B. Johnson wrote:
> It does not look like the 'gcc folks' have spent much time optimizing
> bit operations.
As far as Linux is concerned #include <linux/bitops.h> for optimised
test/set/clear bit operations (that are also used within the kernel).
I also have a patch somewhere for the various bitops.h that fixes all
the missing const qualifiers.
> Bit manipulation on most machines is not speed-efficient, instead it's
> space-efficient. The fastest running sort, for instance, would have
> a bunch of long keys that are being sorted, one key per record, rather
> than bit-fields, each defining a record.
This may be taking things out of context... but some sorts are
extremely fast. Sorting unique integers within reasonably small ranges
can be done with just loop of set_bit and then a linear scan with
find_next_set_bit.
As to the original question, I don't know what a state space machine
is or how large the array is, I'll be tacit.
Giuliano.
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