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Re: Continuations, basic blocks, loops and register allocation

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From:
Matt Fowles
Date:
November 16, 2004 12:12
Subject:
Re: Continuations, basic blocks, loops and register allocation
Message ID:
f2601a7f0411161212b62359b@mail.gmail.com
Dan~

On Tue, 16 Nov 2004 13:41:25 -0500, Dan Sugalski <dan@sidhe.org> wrote:
> At 10:32 AM -0800 11/16/04, Jeff Clites wrote:
> >The continuation preserves the frame (the mapping from logical
> >variables to their values), but not the values of those variables at
> >the time the continuation was created.
> 
> This is one of the fundamental properties of continuations, but it
> does throw people. And it's why register contents have to be thrown
> away when a continuation is invoked, since the registers have values,
> and continuations don't preserve values.

I think right here we have the crux of my failure to understand.  I
was/am under the impression that the continuation will restore the
register frame to exactly as it was when the continuation was taken. 
Thus those registers which are values (I,N) will continue to have the
value they had when the continuation was taken, while those registers
which are pointers/references (S, P) will still point to the same
place, but that data may have changed.  Is this correct?

Matt
-- 
"Computer Science is merely the post-Turing Decline of Formal Systems Theory."
-???

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