Merging r278938:

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r278938 | mcrosier | 2016-08-17 08:54:39 -0700 (Wed, 17 Aug 2016) | 5 lines

Revert "Reassociate: Reprocess RedoInsts after each inst".

This reverts commit r258830, which introduced a bug described in PR28367.

PR28367
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llvm-svn: 278993