On Fri, Mar 14, 2014 at 08:52:07AM +0100, Richard Biener wrote:
> > Consider this fact and if there are alias checks, we can safely remove
> > the epilogue if the maximum trip count of the loop is less than or
> > equal to the calculated threshold.
>
> You have to consider n % vf != 0, so an argument on only maximum
> trip count or threshold cannot work.
Well, if you only check if maximum trip count is <= vf and you know
that for n < vf the vectorized loop + it's epilogue path will not be taken,
then perhaps you could, but it is a very special case.
Now, the question is when we are guaranteed we enter the scalar versioned
loop instead for n < vf, is that in case of versioning for alias or
versioning for alignment?
Jakub
