Merging r278559:

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r278559 | efriedma | 2016-08-12 13:28:02 -0700 (Fri, 12 Aug 2016) | 7 lines

[AArch64LoadStoreOpt] Handle offsets correctly for post-indexed paired loads.

Trunk would try to create something like "stp x9, x8, [x0], #512", which isn't actually a valid instruction.

Differential revision: https://reviews.llvm.org/D23368


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llvm-svn: 279123