Merging r286944:

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r286944 | abataev | 2016-11-15 09:11:50 +0000 (Tue, 15 Nov 2016) | 6 lines

[OPENMP] Fixed codegen for 'omp cancel' construct.

If 'omp cancel' construct is used in a worksharing construct it may cause
hanging of the software in case if reduction clause is used. Patch fixes
this problem by avoiding extra reduction processing for branches that
were canceled.
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git-svn-id: https://llvm.org/svn/llvm-project/cfe/branches/release_39@286968 91177308-0d34-0410-b5e6-96231b3b80d8