Do not use dyn_cast<> after isa<>

[oota-llvm.git] / lib / CodeGen / SelectionDAG / DAGCombiner.cpp

diff --git a/lib/CodeGen/SelectionDAG/DAGCombiner.cpp b/lib/CodeGen/SelectionDAG/DAGCombiner.cpp
index d58c33a499da399a55a87fd72e24872ab7dd02ec..ab3a6631d3393ffb569189e53d443c792f23e6ef 100644 (file)
--- a/lib/CodeGen/SelectionDAG/DAGCombiner.cpp
+++ b/lib/CodeGen/SelectionDAG/DAGCombiner.cpp
@@ -4455,6 +4455,14 @@ SDValue DAGCombiner::visitSHL(SDNode *N) {
     return DAG.getNode(ISD::ADD, SDLoc(N), VT, Shl0, Shl1);
   }
 
+  // fold (shl (mul x, c1), c2) -> (mul x, c1 << c2)
+  if (N1C && N0.getOpcode() == ISD::MUL && N0.getNode()->hasOneUse()) {
+    if (ConstantSDNode *N0C1 = isConstOrConstSplat(N0.getOperand(1))) {
+      SDValue Folded = DAG.FoldConstantArithmetic(ISD::SHL, SDLoc(N1), VT, N0C1, N1C);
+      return DAG.getNode(ISD::MUL, SDLoc(N), VT, N0.getOperand(0), Folded);
+    }
+  }
+
   if (N1C && !N1C->isOpaque())
     if (SDValue NewSHL = visitShiftByConstant(N, N1C))
       return NewSHL;
@@ -12270,7 +12278,7 @@ static SDValue combineConcatVectorOfExtracts(SDNode *N, SelectionDAG &DAG) {
     EVT ExtVT = ExtVec.getValueType();
     if (!isa<ConstantSDNode>(Op.getOperand(1)))
       return SDValue();
-    int ExtIdx = dyn_cast<ConstantSDNode>(Op.getOperand(1))->getZExtValue();
+    int ExtIdx = cast<ConstantSDNode>(Op.getOperand(1))->getZExtValue();
 
     // Ensure that we are extracting a subvector from a vector the same
     // size as the result.