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From: kenner@vlsi1.ultra.nyu.edu (Richard Kenner)
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Date: Wed, 04 May 2011 13:39:00 -0000
To: dnovillo@google.com
Subject: Re: [google]: initialize language field for clone function struct
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> I think we may be talking at different levels.  It's my impression
> that Richard K. was referring to local transformations like "a - a" ->
> "0" once we are in the middle end.  I agree that doing that
> transformation close to the FE is undesirable, but once we are in the
> middle end that should be fine.

That's exactly what I mean.  If the FE cares about no folding taking
place, it shouldn't fold.  But once we're past the point that it's doing
syntax and semantic checking, there's no optimization benefit in deferring
the folding until we get to SSA, for example.