Merging r257940:

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r257940 | djg | 2016-01-15 13:56:40 -0800 (Fri, 15 Jan 2016) | 10 lines

[SelectionDAG] CSE nodes with differing SDNodeFlags

In the optimizer (GVN etc.) when eliminating redundant nodes with different
flags, the flags are ignored for the purposes of testing for congruence, and
then intersected for the purposes of producing a result that supports the union
of all the uses. This commit makes SelectionDAG's CSE do the same thing,
allowing it to CSE nodes in more cases. This fixes PR26063.

Differential Revision: http://reviews.llvm.org/D15957

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Merging r257942:
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r257942 | djg | 2016-01-15 14:07:35 -0800 (Fri, 15 Jan 2016) | 2 lines

Remove a now-empty file left behind by r257940.

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git-svn-id: https://llvm.org/svn/llvm-project/llvm/branches/release_38@258351 91177308-0d34-0410-b5e6-96231b3b80d8