Merging r226791:

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r226791 | delena | 2015-01-22 00:20:06 -0800 (Thu, 22 Jan 2015) | 7 lines

Fixed a bug in masked load/store in reversed loop.
Added a test.

The bug was submitted to bugzilla:
http://llvm.org/bugs/show_bug.cgi?id=22225


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git-svn-id: https://llvm.org/svn/llvm-project/llvm/branches/release_36@229555 91177308-0d34-0410-b5e6-96231b3b80d8