[PATCH] Add support to vectorize ctlz, cttz and powi intrinsics in SLPVectorizer

[Arnold Schwaighofer]

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Comment at: lib/Transforms/Vectorize/SLPVectorizer.cpp:983
@@ +982,3 @@
+            ID == Intrinsic::powi) {
+          Value *A1J = CI2->getArgOperand(1);
+          if (A1I != A1J) {
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The code is repeated three times in this file and likely will make it into the loop vectorizer, too. Can this be refactor into a utility function 'bool hasVectorInstrinsicScalarOpd(ID, unsigned &ScalarOpdIdx)' in VectorUtils.h? (once we have instructions with more than one operand we can change this to be a vector of operands but there is no need now I think)

http://reviews.llvm.org/D3851