Path: utzoo!utgpu!attcan!uunet!seismo!sundc!pitstop!sun!decwrl!decvax!ima!johnl
From: johnl@ima.ima.isc.com (John R. Levine)
Newsgroups: comp.arch
Subject: Re: register save/restore
Message-ID: <2849@ima.ima.isc.com>
Date: 3 Nov 88 02:14:23 GMT
References: <3300037@m.cs.uiuc.edu> <5938@killer.DALLAS.TX.US> <7580@aw.sei.cmu.edu>
Reply-To: johnl@ima.UUCP (John R. Levine)
Organization: Not much
Lines: 14

In article <7580@aw.sei.cmu.edu> firth@bd.sei.cmu.edu (Robert Firth) writes:
>Which is better - caller saves or callee saves?
>
>[he argues that for a variety of reasons, caller saves is faster.]

The argument I most often heard for the callee saving the registers is that
it makes the object code smaller.  Most subroutines are called from more than
one place (otherwise, why make it a subroutine?  I know, libraries, modularity,
etc.) so that you would need N copies of caller-saves, one for each call,
but you only need one copy of callee-saves.
-- 
John R. Levine, IECC, PO Box 349, Cambridge MA 02238-0349, +1 617 492 3869
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