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From: dewar@merv.cs.nyu.edu (Robert Dewar)
Subject: Re: fixed point vs floating point
Date: 1997/11/25
Message-ID: <dewar.880514251@merv>#1/1
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Date: 1997-11-25T00:00:00+00:00
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<<Table lookup has been an important speed optimization for many years,
but does it still work well on newer processors? My experience is that
I don't get the speed improvements that I expect, probably due to the
increasing penalty for cache misses on faster processors. The trend
seems to be that branch-free pipelined code will run faster than table
lookups. Have optimizing compilers kept up with the shifting
tradeoffs?
>>

By the way, it is not branches that are expensive, but mispredicted
branches. With good branch prediction, branches can be almost free.