[PATCH] Improve Cost model for SLPVectorizer when we have a vector division by power of 2

[Sanjay Patel]

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Comment at: lib/Transforms/Vectorize/LoopVectorize.cpp:5848
@@ +5847,3 @@
+    if (isa<ConstantInt>(Op2)) {
+      ConstantInt *CInt = cast<ConstantInt>(Op2);
+      if (CInt && CInt->getValue().isPowerOf2())
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Replace isa<> and cast<> with a dyn_cast<>?
http://llvm.org/docs/ProgrammersManual.html#the-isa-cast-and-dyn-cast-templates

http://reviews.llvm.org/D4971