Merging r229495:

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r229495 | delena | 2015-02-17 05:10:05 -0800 (Tue, 17 Feb 2015) | 8 lines

Fixed a bug in store sinking.
The problem was in store-sink barrier check.

Store sink barrier should be checked for ModRef (read-write) mode.

http://llvm.org/bugs/show_bug.cgi?id=22613


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git-svn-id: https://llvm.org/svn/llvm-project/llvm/branches/release_36@229564 91177308-0d34-0410-b5e6-96231b3b80d8