During post-legalization DAG combining, be careful to only create shifts where the RHS is of the legal type for the new operation.
llvm-svn: 129484
diff --git a/llvm/lib/CodeGen/SelectionDAG/TargetLowering.cpp b/llvm/lib/CodeGen/SelectionDAG/TargetLowering.cpp
index 4b0822d..9bd7dd9 100644
--- a/llvm/lib/CodeGen/SelectionDAG/TargetLowering.cpp
+++ b/llvm/lib/CodeGen/SelectionDAG/TargetLowering.cpp
@@ -1678,6 +1678,13 @@
ConstantSDNode *ShAmt = dyn_cast<ConstantSDNode>(In.getOperand(1));
if (!ShAmt)
break;
+ SDValue Shift = In.getOperand(1);
+ if (TLO.LegalTypes()) {
+ uint64_t ShVal = ShAmt->getZExtValue();
+ Shift =
+ TLO.DAG.getConstant(ShVal, getShiftAmountTy(Op.getValueType()));
+ }
+
APInt HighBits = APInt::getHighBitsSet(OperandBitWidth,
OperandBitWidth - BitWidth);
HighBits = HighBits.lshr(ShAmt->getZExtValue()).trunc(BitWidth);
@@ -1691,7 +1698,7 @@
return TLO.CombineTo(Op, TLO.DAG.getNode(ISD::SRL, dl,
Op.getValueType(),
NewTrunc,
- In.getOperand(1)));
+ Shift));
}
break;
}