Merging r340641:

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r340641 | stefanp | 2018-08-24 21:38:29 +0200 (Fri, 24 Aug 2018) | 9 lines

[Exception Handling] Unwind tables are required for all functions that have an EH personality.

This patch is for defect:
https://bugs.llvm.org/show_bug.cgi?id=32611

Functions may require unwind tables even if they are marked with the attribute
nounwind. Any function with an EH personality may require an unwind table.

Differential Revision: https://reviews.llvm.org/D50987
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git-svn-id: https://llvm.org/svn/llvm-project/llvm/branches/release_70@340731 91177308-0d34-0410-b5e6-96231b3b80d8