reversing a mask

Ken Yap ken at rochester.UUCP
Sun Nov 25 16:59:27 AEST 1984


>What's the fastest way to reverse a 16-bit mask in C?  In 68000 asl?

Actually the 65536 combination answer wasn't too far from a plausible
method - split the word up into 2 8 bit bytes and then do two lookups.
Then swap bytes.  This way you only need one 256 byte table.

You could do lookups on nybbles, etc, ad nauseum.
-- 
	Ken Yap

	UUCP:	(..!{allegra, decvax, seismo}!rochester!ken)
	ARPA:	ken at rochester.arpa
	USnail:	Ken Yap, Dept. of Comp. Sci., U. of Rochester, NY 14627.



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