Merging r279930:

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r279930 | elena.demikhovsky | 2016-08-28 01:53:53 -0700 (Sun, 28 Aug 2016) | 7 lines

[Loop Vectorizer] Fixed memory confilict checks.

Fixed a bug in run-time checks for possible memory conflicts inside loop.
The bug is in Low <-> High boundaries calculation. The High boundary
should be calculated as "last memory access pointer + element size".

Differential revision: https://reviews.llvm.org/D23176

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llvm-svn: 287779