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Re: [PATCH] Fix optimization regression in constant folder


> It looks like giving sizetype mode_for_size (GET_MODE_SIZE
> (Pmode)) (or similar) while raising its precision to cover the full
> 2 * HWI could do the right thing for constants and expansion.

I'm not sure what you mean.  That mode has a lower precision, but if
you use that wider precision it become VERY expensive do all
arithmetic at run time in that wider precision.  sizetype needs to be
at least as wide as needed for correctness purposes but no wider than
needed for efficiency purposes.


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