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Re: [PATCH] Fix optimization regression in constant folder


> 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.

You're rewriting history, sizetype semantics already exists, just look at the 
definition of TYPE_IS_SIZETYPE in tree.h and its uses in fold-const.c.

> Look at all the places we _don't_specialize sizetypes!  You want to audit
> all these? 

No, we just want to avoid consciously harming the compiler.  In my experience,
a single line in fold-const.c can sometimes be more effective than an entire 
optimization pass.

--
Eric Botcazou


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