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Re: signed overflow in atan2

On Wed, Mar 07, 2018 at 05:56:21PM +0700, Robert Elz wrote:
>     Date:        Wed, 7 Mar 2018 00:33:04 -0800
>     From:        Eitan Adler <>
>     Message-ID:  <>
>    | I'd like to commit the patch below. Does anyone have concerns with it?
> The change looks fine technically, but it would be good to see some benchmark
> results before committing it - particularly for the more common case where
> x != 1.0 (but including where x == 2.0 or 0.5) - the change swiches from using
> arithmetic and a single branch to multiple branches (or would with simplisitc
> compilation) and branches are slow wrt prefetch and parallel execution.

I don't see the point other than submitting compiler bug reports. This
is a transformation typically done already.


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