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Re: [PATCH] Fix optimization regression in constant folder


Ian Lance Taylor wrote:

>>> But the rest of us don't understand the semantics of sizetypes.  That
>>> is why we are trying to pin it down in terms of other flags.  We
>>> understand what those other flags mean.

Right.  I don't think it's important per se whether or not we have a
TYPE_IS_SIZETYPE flag or not.  But, I do think it's important that we
define the semantics of sizetypes, if we're going to use them.

I agree with others in this thread that I don't understand what you
think the semantics are.  I do understand the goal: permit more
optimizations of expressions involving sizetypes.  But, I don't
understand what the semantics are that achieve that goal.

Kenner, perhaps you could define the semantics as differences from an
ordinary integer type?  "A sizetype is like an ordinary INTEGER_TYPE,
except that ..."?

-- 
Mark Mitchell
CodeSourcery
mark@codesourcery.com
(650) 331-3385 x713


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