Article View: comp.sys.super
Article #502Re: How many vector registers are useful?
From: James Davies
Date: Wed, 27 Jan 1993 16:40
Date: Wed, 27 Jan 1993 16:40
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kirchner@uklira.informatik.uni-kl.de (Reinhard Kirchner) writes:
> A register has an optimizing effect only when the value in it can be used
> several times, ...
jlg@cochiti.lanl.gov (J. Giles) writes:
>... The other [optimization] (also true of scalars) is when the value is
>an intermediate.
Actually, there's a third effect: on machines with multiple functional
units a load or store to/from a register can be done at the same time as
other operations, so that the register can act like a small programmable
cache (complete with prefetching).
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Newsgroups: comp.sys.super,comp.arch,comp.compilers Path: arc1-ca.pugleaf.net!sparky!uunet!think.com!spdcc!iecc!compilers-sender From: jrbd@craycos.com (James Davies) Subject: Re: How many vector registers are useful? Reply-To: jrbd@craycos.com (James Davies) Organization: Cray Computer Corporation Date: Wed, 27 Jan 1993 16:40:35 GMT Approved: compilers@iecc.cambridge.ma.us Message-ID: <93-01-202@comp.compilers> References: <93-01-174@comp.compilers> <93-01-195@comp.compilers> Keywords: architecture, vector Sender: compilers-sender@iecc.cambridge.ma.us Lines: 15