Merging r182656:

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r182656 | d0k | 2013-05-24 11:05:35 -0700 (Fri, 24 May 2013) | 3 lines

LoopVectorize: LoopSimplify can't canonicalize loops with an indirectbr in it, don't assert on those cases.

Fixes PR16139.
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llvm-svn: 182785