Path: utzoo!utgpu!jarvis.csri.toronto.edu!mailrus!wasatch!cdr.utah.edu!moore
From: moore%cdr.utah.edu@wasatch.UUCP (Tim Moore)
Newsgroups: comp.arch
Subject: Re: RISC & context switches
Message-ID: <1101@wasatch.UUCP>
Date: 12 Feb 89 22:52:34 GMT
References: <784@atanasoff.cs.iastate.edu> <7239@june.cs.washington.edu> <89Feb12.125852est.10867@ephemeral.ai.toronto.edu>
Sender: news@wasatch.UUCP
Reply-To: moore%cdr.utah.edu.UUCP@wasatch.UUCP (Tim Moore)
Organization: University of Utah, Computer Science Dept.
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In article <89Feb12.125852est.10867@ephemeral.ai.toronto.edu> bradb@ai.toronto.edu (Brad Brown) writes:

)There is a somewhat related problem when you make a subroutine call --
)the calling function usually has to save its registers so it gets it's
)"context" restored when the function returns.  Machines like MIPS have
)made use of their very large number of registers (192?) by having a pointer
)to one of the registers that is effectively the base pointer for the
)stack of registers that the currently executing function can use.

You're confusing MIPS and SPARC here. The MIPS chips have a fairly
conventional set of general registers; SPARC has a large file of
registers that are divided into "windows" in the manner you describe.


			-Tim Moore
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