Iterating over a DenseMap<std::pair<BasicBlock*, unsigned>, PHINode*> is not deterministic, replace it with a DenseMap<std::pair<unsigned, unsigned>, PHINode*> (we already have a map from BasicBlock to unsigned).
Iterating over a DenseMap<std::pair<BasicBlock*, unsigned>, PHINode*> is not
deterministic, replace it with a DenseMap<std::pair<unsigned, unsigned>,
PHINode*> (we already have a map from BasicBlock to unsigned).

<rdar://problem/12541389>


git-svn-id: 0ff597fd157e6f4fc38580e8d64ab130330d2411@166435 91177308-0d34-0410-b5e6-96231b3b80d8

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