[llvm] r294129 - [SelectionDAG] In InstrEmitter, handle EXTRACT_SUBREG of a physical register.

[Geoff Berry via llvm-commits]

Adding Quentin since he reviewed the original change

On 2/14/2017 2:07 PM, Hans Wennborg wrote:
> Ping?
>
> On Mon, Feb 6, 2017 at 1:43 PM, Hans Wennborg <hans at chromium.org> wrote:
>> Hi Justin,
>>
>> Geoff suggested this should be merged to 4.0. What do you think as
>> SelectionDAG owner?
>>
>> Thanks,
>> Hans
>>
>> On Sun, Feb 5, 2017 at 10:28 AM, Geoff Berry via llvm-commits
>> <llvm-commits at lists.llvm.org> wrote:
>>> Author: gberry
>>> Date: Sun Feb  5 12:28:14 2017
>>> New Revision: 294129
>>>
>>> URL: http://llvm.org/viewvc/llvm-project?rev=294129&view=rev
>>> Log:
>>> [SelectionDAG] In InstrEmitter, handle EXTRACT_SUBREG of a physical register.
>>>
>>> Summary:
>>> Without this change, the getVR() call would hit an assert since it was
>>> being passed a physical register.
>>>
>>> Update the AArch64/ldst-opt.ll test with a case that triggers this
>>> behavior by adding a run with strict-align, which causes an unaligned
>>> STR XZR instruction to be split into byte stores, creating an
>>> EXTRACT_SUBREG of XZR that triggers the original problem.
>>>
>>> Reviewers: bogner, qcolombet, MatzeB, atrick
>>>
>>> Subscribers: aemerson, mcrosier, llvm-commits
>>>
>>> Differential Revision: https://reviews.llvm.org/D29495
>>>
>>> Modified:
>>>      llvm/trunk/lib/CodeGen/SelectionDAG/InstrEmitter.cpp
>>>      llvm/trunk/test/CodeGen/AArch64/ldst-opt.ll

-- 
Geoff Berry
Employee of Qualcomm Datacenter Technologies, Inc.
  Qualcomm Datacenter Technologies, Inc. as an affiliate of Qualcomm Technologies, Inc.  Qualcomm Technologies, Inc. is a member of the Code Aurora Forum, a Linux Foundation Collaborative Project.