Re: Frequency of integer division in source code?

meissner@osf.org writes:
>Another place where division (actually modulus) is used quite
>frequently is in calculating hash tables, which often involves modulus
>by a prime number constant. This of course lends itself nicely to
>being replaced by multiplication.


Better yet is not to be mis-lead by Maurer's paper and to ignore his
advice by using a table whose size is a power of two. Then the integer
divide becomes an AND operation which is faster that division or
multiplication on almost all architectures.


The ``theory'' of using powers of two is explained in various papers by
Hopgood et all from the late-60/early-70s.


--
Regards, Trevor.
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Trevor Jenkins
134 Frankland Rd, Croxley Green, RICKMANSWORTH, WD3 3AU, England
email: tfj@apusapus.demon.co.uk phone: +44 (0)923 776436 radio: G6AJG
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