Merging r258319:

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r258319 | thomas.stellard | 2016-01-20 07:48:27 -0800 (Wed, 20 Jan 2016) | 8 lines

Correctly initialize SIAnnotateControlFlow

Reviewers: arsenm

Subscribers: arsenm, llvm-commits

Differential Revision: http://reviews.llvm.org/D16304

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llvm-svn: 271483