Merging r259375:

Merging r259375:
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r259375 | majnemer | 2016-02-01 09:37:56 -0800 (Mon, 01 Feb 2016) | 6 lines

[InstCombine] Don't transform (X+INT_MAX)>=(Y+INT_MAX) -> (X<=Y)

This miscompile came about because we tried to use a transform which was
only appropriate for xor operators when addition was present.

This fixes PR26407.
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git-svn-id: https://llvm.org/svn/llvm-project/llvm/branches/release_38@259390 91177308-0d34-0410-b5e6-96231b3b80d8