Merging r278370:

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r278370 | mkuper | 2016-08-11 10:38:33 -0700 (Thu, 11 Aug 2016) | 7 lines

Make TwoAddressInstructionPass::rescheduleMIBelowKill subreg-aware

This fixes PR28824.

Differential Revision: https://reviews.llvm.org/D23220


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llvm-svn: 278422