Article View: comp.arch
Article #2995Re: Software modularity vs. instruction locality
From: H.Shrikumar{shri
Date: Mon, 06 Nov 1989 20:36
Date: Mon, 06 Nov 1989 20:36
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1680 bytes
In article <1TMk2X#Qggn6=eric@snark.uu.net> eric@snark.uu.net (Eric S. Raymond) writes: >In <1989Nov4.004529.10049@ico.isc.com> Dick Dunn wrote: >> Second, I would expect better locality >> for code reference than for data reference, hence the I cache ought to do >> more good than the D cache. Aren't the pathological cache-busting programs >> generally ones which spray data accesses all over the place? > >Not necessarily. There's a subtle problem here; good software modularity >practices tend to hurt code locality. If you're calling subroutines a lot >in generated code the PC jumps all over the shop. This happens for example in a FORTH machine, FORTH typically is subroutine threaded, so there is a flurry of subroutine calls happening at about 4 million a second. (in a 8-10 Mhz (?) Novix 2016 Forth CPU). In forth there is a subroutine call every five or so instructions I would guess. Wonder if some better cache philosophy can help here. -- shrikumar ( shri@ccs1.cs.umass.edu, shri@ncst.in )
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From: shri@ccs1.cs.umass.edu (H.Shrikumar{shri@ncst.in})
Newsgroups: comp.arch
Subject: Re: Software modularity vs. instruction locality
Message-ID: <6374@dime.cs.umass.edu>
Date: 6 Nov 89 20:36:33 GMT
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