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From: Terry Lambert <tlambert@primenet.com>
Message-Id: <200005182045.NAA21595@usr08.primenet.com>
Subject: Re: Sparc & api for asynchronous task execution (2)
To: cp@bsdi.com (Chuck Paterson)
Date: Thu, 18 May 2000 20:45:54 +0000 (GMT)
Cc: dfr@nlsystems.com (Doug Rabson), arch@FreeBSD.ORG
In-Reply-To: <200005172056.OAA25889@berserker.bsdi.com> from "Chuck Paterson" at May 17, 2000 02:56:16 PM
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> }I didn't realize that every function call involved a fault on the sparc
> }architecture - that sounds pretty nasty.
> 
> 	Actually every function call doesn't cause a fault, every
> time you overflow/underflow the current set of register windows causes a
> fault. (Perhaps what you meant). This means that calling a function
> from the bottom most function will cause two faults, one for going down
> and one eventually as you go up.
> 
> 	This makes going up and down when you don't overflow
> very fast at the expense of when you add to the total depth.

See also:

	TR-91-08-01
	Register Windows and User-Space Threads on the SPARC
	D. Keppel
	August 1991
	University of Washington
	ftp://ftp.cs.washington.edu/tr/1991/08/UW-CSE-91-08-01.PS.Z

for a good discussion of SPARC register windows.


					Terry Lambert
					terry@lambert.org
---
Any opinions in this posting are my own and not those of my present
or previous employers.


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