diff --git a/llvm/lib/Target/X86/X86ISelLowering.cpp b/llvm/lib/Target/X86/X86ISelLowering.cpp index 1a81a3ed4811..6ca24f5ca780 100644 --- a/llvm/lib/Target/X86/X86ISelLowering.cpp +++ b/llvm/lib/Target/X86/X86ISelLowering.cpp @@ -5681,13 +5681,8 @@ SDValue X86TargetLowering::EmitCmp(SDValue Op0, SDValue Op1, unsigned X86CC, return DAG.getNode(X86ISD::CMP, dl, MVT::i32, Op0, Op1); } -SDValue X86TargetLowering::LowerSETCC(SDValue Op, SelectionDAG &DAG) { - assert(Op.getValueType() == MVT::i8 && "SetCC type must be 8-bit integer"); - SDValue Op0 = Op.getOperand(0); - SDValue Op1 = Op.getOperand(1); - DebugLoc dl = Op.getDebugLoc(); - ISD::CondCode CC = cast(Op.getOperand(2))->get(); - +static SDValue LowerToBT(SDValue Op0, SDValue Op1, ISD::CondCode CC, + DebugLoc dl, SelectionDAG &DAG) { // Lower (X & (1 << N)) == 0 to BT(X, N). // Lower ((X >>u N) & 1) != 0 to BT(X, N). // Lower ((X >>s N) & 1) != 0 to BT(X, N). @@ -5699,14 +5694,14 @@ SDValue X86TargetLowering::LowerSETCC(SDValue Op, SelectionDAG &DAG) { SDValue LHS, RHS; if (Op0.getOperand(1).getOpcode() == ISD::SHL) { if (ConstantSDNode *Op010C = - dyn_cast(Op0.getOperand(1).getOperand(0))) + dyn_cast(Op0.getOperand(1).getOperand(0))) if (Op010C->getZExtValue() == 1) { LHS = Op0.getOperand(0); RHS = Op0.getOperand(1).getOperand(1); } } else if (Op0.getOperand(0).getOpcode() == ISD::SHL) { if (ConstantSDNode *Op000C = - dyn_cast(Op0.getOperand(0).getOperand(0))) + dyn_cast(Op0.getOperand(0).getOperand(0))) if (Op000C->getZExtValue() == 1) { LHS = Op0.getOperand(1); RHS = Op0.getOperand(0).getOperand(1); @@ -5740,6 +5735,21 @@ SDValue X86TargetLowering::LowerSETCC(SDValue Op, SelectionDAG &DAG) { } } + return SDValue(); +} + +SDValue X86TargetLowering::LowerSETCC(SDValue Op, SelectionDAG &DAG) { + assert(Op.getValueType() == MVT::i8 && "SetCC type must be 8-bit integer"); + SDValue Op0 = Op.getOperand(0); + SDValue Op1 = Op.getOperand(1); + DebugLoc dl = Op.getDebugLoc(); + ISD::CondCode CC = cast(Op.getOperand(2))->get(); + + // Optimize to BT if possible. + SDValue NewCond = LowerToBT(Op0, Op1, CC, dl, DAG); + if (NewCond.getNode()) + return NewCond; + bool isFP = Op.getOperand(1).getValueType().isFloatingPoint(); unsigned X86CC = TranslateX86CC(CC, isFP, Op0, Op1, DAG); if (X86CC == X86::COND_INVALID)