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Re: [PATCH Atom][PR middle-end/44382] Tree reassociation improvement
On Wed, Jul 13, 2011 at 11:18 AM, Ilya Enkovich <enkovich.gnu@gmail.com> wrote:
> 2011/7/13 Jakub Jelinek <jakub@redhat.com>:
>>
>> I disagree. ?Widening would result in worse code in most cases, as you need
>> to sign extend all the operands. ?On the other side, I doubt you can
>> actually usefully use the undefinedness of signed overflow for a series of
>> 3 or more operands of the associative operation.
>>
>> ? ? ? ?Jakub
>>
>
> Sounds reasonable. Type casting to unsigned should be a better solution here.
Well, the solution of course lies in the no-undefined-overflow branch
where we have separate tree codes for arithmetic with/without
undefined overflow.
Richard.
> Ilya
>