//==-- MSP430ISelLowering.h - MSP430 DAG Lowering Interface ------*- C++ -*-==//
//
//                     The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file defines the interfaces that MSP430 uses to lower LLVM code into a
// selection DAG.
//
//===----------------------------------------------------------------------===//

#ifndef LLVM_TARGET_MSP430_ISELLOWERING_H
#define LLVM_TARGET_MSP430_ISELLOWERING_H

#include "MSP430.h"
#include "llvm/CodeGen/SelectionDAG.h"
#include "llvm/Target/TargetLowering.h"

namespace llvm {
  namespace MSP430ISD {
    enum {
      FIRST_NUMBER = ISD::BUILTIN_OP_END,

      /// Return with a flag operand. Operand 0 is the chain operand.
      RET_FLAG,

      /// Y = R{R,L}A X, rotate right (left) arithmetically
      RRA, RLA,

      /// Y = RRC X, rotate right via carry
      RRC,

      /// CALL - These operations represent an abstract call
      /// instruction, which includes a bunch of information.
      CALL,

      /// Wrapper - A wrapper node for TargetConstantPool, TargetExternalSymbol,
      /// and TargetGlobalAddress.
      Wrapper,

      /// CMP - Compare instruction.
      CMP,

      /// SetCC. Operand 0 is condition code, and operand 1 is the flag
      /// operand produced by a CMP instruction.
      SETCC,

      /// MSP430 conditional branches. Operand 0 is the chain operand, operand 1
      /// is the block to branch if condition is true, operand 2 is the
      /// condition code, and operand 3 is the flag operand produced by a CMP
      /// instruction.
      BR_CC,

      /// SELECT_CC. Operand 0 and operand 1 are selection variable, operand 3
      /// is condition code and operand 4 is flag operand.
      SELECT_CC
    };
  }

  class MSP430Subtarget;
  class MSP430TargetMachine;

  class MSP430TargetLowering : public TargetLowering {
  public:
    explicit MSP430TargetLowering(MSP430TargetMachine &TM);

    /// LowerOperation - Provide custom lowering hooks for some operations.
    virtual SDValue LowerOperation(SDValue Op, SelectionDAG &DAG);

    /// getTargetNodeName - This method returns the name of a target specific
    /// DAG node.
    virtual const char *getTargetNodeName(unsigned Opcode) const;

    /// getFunctionAlignment - Return the Log2 alignment of this function.
    virtual unsigned getFunctionAlignment(const Function *F) const;

    SDValue LowerShifts(SDValue Op, SelectionDAG &DAG);
    SDValue LowerGlobalAddress(SDValue Op, SelectionDAG &DAG);
    SDValue LowerExternalSymbol(SDValue Op, SelectionDAG &DAG);
    SDValue LowerBR_CC(SDValue Op, SelectionDAG &DAG);
    SDValue LowerSELECT_CC(SDValue Op, SelectionDAG &DAG);
    SDValue LowerSIGN_EXTEND(SDValue Op, SelectionDAG &DAG);

    TargetLowering::ConstraintType
    getConstraintType(const std::string &Constraint) const;
    std::pair<unsigned, const TargetRegisterClass*>
    getRegForInlineAsmConstraint(const std::string &Constraint, EVT VT) const;

    MachineBasicBlock* EmitInstrWithCustomInserter(MachineInstr *MI,
                                                   MachineBasicBlock *BB) const;

  private:
    SDValue LowerCCCCallTo(SDValue Chain, SDValue Callee,
                           unsigned CallConv, bool isVarArg,
                           bool isTailCall,
                           const SmallVectorImpl<ISD::OutputArg> &Outs,
                           const SmallVectorImpl<ISD::InputArg> &Ins,
                           DebugLoc dl, SelectionDAG &DAG,
                           SmallVectorImpl<SDValue> &InVals);

    SDValue LowerCCCArguments(SDValue Chain,
                              unsigned CallConv,
                              bool isVarArg,
                              const SmallVectorImpl<ISD::InputArg> &Ins,
                              DebugLoc dl,
                              SelectionDAG &DAG,
                              SmallVectorImpl<SDValue> &InVals);

    SDValue LowerCallResult(SDValue Chain, SDValue InFlag,
                            unsigned CallConv, bool isVarArg,
                            const SmallVectorImpl<ISD::InputArg> &Ins,
                            DebugLoc dl, SelectionDAG &DAG,
                            SmallVectorImpl<SDValue> &InVals);

    virtual SDValue
      LowerFormalArguments(SDValue Chain,
                           unsigned CallConv, bool isVarArg,
                           const SmallVectorImpl<ISD::InputArg> &Ins,
                           DebugLoc dl, SelectionDAG &DAG,
                           SmallVectorImpl<SDValue> &InVals);
    virtual SDValue
      LowerCall(SDValue Chain, SDValue Callee,
                unsigned CallConv, bool isVarArg, bool isTailCall,
                const SmallVectorImpl<ISD::OutputArg> &Outs,
                const SmallVectorImpl<ISD::InputArg> &Ins,
                DebugLoc dl, SelectionDAG &DAG,
                SmallVectorImpl<SDValue> &InVals);

    virtual SDValue
      LowerReturn(SDValue Chain,
                  unsigned CallConv, bool isVarArg,
                  const SmallVectorImpl<ISD::OutputArg> &Outs,
                  DebugLoc dl, SelectionDAG &DAG);

    const MSP430Subtarget &Subtarget;
    const MSP430TargetMachine &TM;
  };
} // namespace llvm

#endif // LLVM_TARGET_MSP430_ISELLOWERING_H