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Re: [PATCH] Fix optimization regression in constant folder


On 10/1/07, Richard Kenner <kenner@vlsi1.ultra.nyu.edu> wrote:
> > It sounds like you define sizetypes to have infinite precision.
>
> No.  Where did I say that?

It matches undefined overflow && wrapping overflow, as for infinite precision
overflow really cannot happen.

> > Oh, and did I ask for testcases?
>
> I'm talking about how to define the semantics of a certain middle-end
> object (in this case sizetypes).  That doesn't involve test cases.

You say you need special semantics because otherwise optimization won't work.
This needs testcases.  Otherwise just mapping sizetype semantics to an
_existing_ semantic makes most sense as it reduces diversity of semantics
and causes less confusion.  Look at all the places we _don't_ specialize
sizetypes!  You want to audit all these?

Richard.


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