Merging r222856:

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r222856 | majnemer | 2014-11-26 15:00:38 -0800 (Wed, 26 Nov 2014) | 8 lines

Revert "Added inst combine transforms for single bit tests from Chris's note"

This reverts commit r210006, it miscompiled libapr which is used in who
knows how many projects.

A test has been added to ensure that we don't regress again.

I'll work on a rewrite of what the optimization was trying to do later.
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llvm-svn: 225255