[PATCH] D128911: Emit table lookup from TargetLowering::expandCTTZ()

[Craig Topper via Phabricator via llvm-commits]

craig.topper added inline comments.


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Comment at: llvm/lib/CodeGen/SelectionDAG/TargetLowering.cpp:7860
+    ConstantSDNode *IndexNode = dyn_cast<ConstantSDNode>(Index);
+    ConstantInt *temp = const_cast<ConstantInt *>(IndexNode->getConstantIntValue());
+    Constant *ConstantData =  dyn_cast<Constant >(temp);
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`dyn_cast` should only be used if the cast can fail. Otherwise use `cast`


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Comment at: llvm/lib/CodeGen/SelectionDAG/TargetLowering.cpp:7862
+    Constant *ConstantData =  dyn_cast<Constant >(temp);
+    Elt.push_back(ConstantData);
+  }
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Same comment about `dyn_cast`


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Comment at: llvm/lib/CodeGen/SelectionDAG/TargetLowering.cpp:7865
+  ArrayRef<Constant *> Elts = Elt;
+  auto *FPTy = Elts[0]->getType();
+  const DataLayout &TD = DAG.getDataLayout();
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Why do we need to create an explicit ArrayRef here?


CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D128911/new/

https://reviews.llvm.org/D128911