Merging r295215:

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r295215 | arnolds | 2017-02-15 10:57:06 -0800 (Wed, 15 Feb 2017) | 11 lines

ThreadSanitizer: don't track swifterror memory addresses

They are register promoted by ISel and so it makes no sense to treat them as
memory.

Inserting calls to the thread sanitizer would also generate invalid IR.

You would hit:

"swifterror value can only be loaded and stored from, or as a swifterror
argument!"
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llvm-svn: 295376