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Re: [PATCH] Fix result for conditional reductions matching at index 0
On Thu, Nov 23, 2017 at 10:51 AM, Alan Hayward <Alan.Hayward@arm.com> wrote:
>
>> On 22 Nov 2017, at 16:57, Kilian Verhetsel <kilian.verhetsel@uclouvain.be> wrote:
>>
>>
>> Thank you both for your comments.
>>
>> I have added the check to ensure the index vector won't cause an
>> overflow. I also added tests to the testsuite in order to check that the
>> loop is vectorized for UINT_MAX - 1 iterations but not UINT_MAX
>> iterations. I was not able to write code that triggers
>> INTEGER_INDUC_COND_REDUCTION when using char or other smaller types
>> (changing the types of last, min_v and a to something else causes
>> COND_REDUCTION to be used instead), so these tests are only compiled and
>> not executed.
>
> I had similar problems when playing around with -14.c, but didn’t have chance to
> investigate why. Possibly worth raising a bug to mentioning there is a missed
> optimisation. It’d be nice to figure out why.
>
>>
>> I also moved an instruction that generates a vector of zeroes (used for
>> COND_REDUCTION) in the branch of code run only for COND_REDUCTION, this
>> should remove the unused vector that Alan noticed.
>
> Patch is ok for me.
Fine with me as well.
Thanks for taking care of this bug.
Richard.
>
> Alan.
>