Merging r278573 (and r277399, r278157, r278569):

Merging r278573 (and r277399, r278157, r278569):

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r278573 | timshen | 2016-08-12 15:47:13 -0700 (Fri, 12 Aug 2016) | 8 lines

[LoopVectorize] Detect loops in the innermost loop before creating InnerLoopVectorizer

InnerLoopVectorizer shouldn't handle a loop with cycles inside the loop
body, even if that cycle isn't a natural loop.

Fixes PR28541.

Differential Revision: https://reviews.llvm.org/D22952
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r277399 | timshen | 2016-08-01 15:32:20 -0700 (Mon, 01 Aug 2016) | 9 lines

[ADT] NFC: Generalize GraphTraits requirement of "NodeType *" in interfaces to "NodeRef", and migrate SCCIterator.h to use NodeRef

Summary: By generalize the interface, users are able to inject more flexible Node token into the algorithm, for example, a pair of vector<Node>* and index integer. Currently I only migrated SCCIterator to use NodeRef, but more is coming. It's a NFC.

Reviewers: dblaikie, chandlerc

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D22937
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r278157 | timshen | 2016-08-09 13:23:13 -0700 (Tue, 09 Aug 2016) | 7 lines

[ADT] Change iterator_adaptor_base's default template arguments to forward more underlying typedefs

Reviewers: chandlerc

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D23217
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r278569 | timshen | 2016-08-12 15:03:28 -0700 (Fri, 12 Aug 2016) | 3 lines

[ADT] Add filter_iterator for filtering elements

Differential Revision: https://reviews.llvm.org/D22951
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git-svn-id: https://llvm.org/svn/llvm-project/llvm/branches/release_39@278674 91177308-0d34-0410-b5e6-96231b3b80d8