[llvm] r293635 - [DAGCombine] require UnsafeFPMath for re-association of addition

[Hans Wennborg via llvm-commits]

On Wed, Feb 1, 2017 at 9:01 PM, Hal Finkel <hfinkel at anl.gov> wrote:
>
> On 02/01/2017 04:07 PM, Hans Wennborg wrote:
>>
>> The bug was marked as a release-blocker for 4.0, but it sounds like
>> it's not technically a 3.9 regression. Hal, what do you think about
>> merging this?
>
>
> It should be safe to merge.

r293940.

Thanks,
Hans


>> On Tue, Jan 31, 2017 at 6:35 AM, Nicolai Haehnle via llvm-commits
>> <llvm-commits at lists.llvm.org> wrote:
>>>
>>> Author: nha
>>> Date: Tue Jan 31 08:35:37 2017
>>> New Revision: 293635
>>>
>>> URL: http://llvm.org/viewvc/llvm-project?rev=293635&view=rev
>>> Log:
>>> [DAGCombine] require UnsafeFPMath for re-association of addition
>>>
>>> Summary:
>>> The affected transforms all implicitly use associativity of addition,
>>> for which we usually require unsafe math to be enabled.
>>>
>>> The "Aggressive" flag is only meant to convey information about the
>>> performance of the fused ops relative to a fmul+fadd sequence.
>>>
>>> Fixes Bug 31626.
>>>
>>> Reviewers: spatel, hfinkel, mehdi_amini, arsenm, tstellarAMD
>>>
>>> Subscribers: jholewinski, nemanjai, wdng, llvm-commits
>>>
>>> Differential Revision: https://reviews.llvm.org/D28675
>
>
> --
> Hal Finkel
> Lead, Compiler Technology and Programming Languages
> Leadership Computing Facility
> Argonne National Laboratory
>