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Date: Fri, 12 Dec 2003 19:42:00 -0000
From: Zdenek Dvorak <rakdver@atrey.karlin.mff.cuni.cz>
To: Andrew MacLeod <amacleod@redhat.com>
Cc: Chris Lattner <sabre@nondot.org>, Jeff Law <law@redhat.com>,
	gcc mailing list <gcc@gcc.gnu.org>
Subject: Re: [tree-ssa] Lazy updating of stmt operands
Message-ID: <20031212192459.GA9411@atrey.karlin.mff.cuni.cz>
References: <Pine.LNX.4.44.0312112134170.5198-100000@nondot.org> <1071256652.14001.265.camel@p4>
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Hello,

> I suspect the loop optimizations are going to fall into the same
> category as CCP in that they are going to be interested in the immediate
> uses of only a partial subset of variables most of the time. I think its
> far more efficient to calculate those when you need them/know what they
> are, and possibly maintain just those def->uses.

hardly; you still must scan all statements to find the uses, so I don't
see where you would want to get the extra efficiency.

Zdenek