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Re: Minor CCP improvement and add comments to tree.h
On Fri, 2004-09-24 at 10:16, Daniel Berlin wrote:
> On Sep 24, 2004, at 1:21 AM, Jeffrey A Law wrote:
>
> > On Thu, 2004-09-23 at 09:06, Daniel Berlin wrote:
> >
> >
> >>> I should have asked in a different way. Let's assume I'm changing
> >>> the form of an expression, but not its actual value. For example,
> >>> we might change a division into a shift or a modulo into a bitwise
> >>> and. We're careful not to apply such transformations when it would
> >>> change the value of the expression, though they do change the form
> >>> of the underlying expression -- which might in turn change the
> >>> VALUE_HANDLE, depending on how it's computed.
> >> It could change the value handle, but it doesn't actually have to if
> >> you don't want it to (since we *know* they are the same value,
> >> regardless of whether *it* knows they are).
> > I had pondered this -- something about leaving the VALUE_HANDLES
> > unchanged in this circumstance makes me uneasy.
>
> Yes, it made me uneasy too.
You are both making me uneasy :-)
Andrew