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To: Andrew MacLeod <amacleod@redhat.com>
CC: gcc@gcc.gnu.org
Subject: Re: [tree-ssa][ GC, Virtual operands, and GCing between passes
References: <1070998524.17667.2860.camel@p4>
From: Geoff Keating <geoffk@geoffk.org>
Date: Tue, 09 Dec 2003 23:43:00 -0000
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Andrew MacLeod <amacleod@redhat.com> writes:

> Are we sure we want to GC between passes? :-|
> 
> since VDEFs and VUSEs are tree nodes, I can't allocate the structure
> which holds them anywhere except GC'd memory can I?
> 
> ie
> 
> a_3 = VDEF <a_2>
> 
> This requires points to 2 trees.
> 
> the GC system has to know not to collect the trees I am pointing to in
> the 2 words of the vdef vector.
> 
> but I dont want to GC the vdef vector.

Why not?

-- 
- Geoffrey Keating <geoffk@geoffk.org>