1 //===-- MSP430ISelLowering.h - MSP430 DAG Lowering Interface ----*- C++ -*-===// 2 // 3 // The LLVM Compiler Infrastructure 4 // 5 // This file is distributed under the University of Illinois Open Source 6 // License. See LICENSE.TXT for details. 7 // 8 //===----------------------------------------------------------------------===// 9 // 10 // This file defines the interfaces that MSP430 uses to lower LLVM code into a 11 // selection DAG. 12 // 13 //===----------------------------------------------------------------------===// 14 15 #ifndef LLVM_TARGET_MSP430_ISELLOWERING_H 16 #define LLVM_TARGET_MSP430_ISELLOWERING_H 17 18 #include "MSP430.h" 19 #include "llvm/CodeGen/SelectionDAG.h" 20 #include "llvm/Target/TargetLowering.h" 21 22 namespace llvm { 23 namespace MSP430ISD { 24 enum { 25 FIRST_NUMBER = ISD::BUILTIN_OP_END, 26 27 /// Return with a flag operand. Operand 0 is the chain operand. 28 RET_FLAG, 29 30 /// Same as RET_FLAG, but used for returning from ISRs. 31 RETI_FLAG, 32 33 /// Y = R{R,L}A X, rotate right (left) arithmetically 34 RRA, RLA, 35 36 /// Y = RRC X, rotate right via carry 37 RRC, 38 39 /// CALL - These operations represent an abstract call 40 /// instruction, which includes a bunch of information. 41 CALL, 42 43 /// Wrapper - A wrapper node for TargetConstantPool, TargetExternalSymbol, 44 /// and TargetGlobalAddress. 45 Wrapper, 46 47 /// CMP - Compare instruction. 48 CMP, 49 50 /// SetCC - Operand 0 is condition code, and operand 1 is the flag 51 /// operand produced by a CMP instruction. 52 SETCC, 53 54 /// MSP430 conditional branches. Operand 0 is the chain operand, operand 1 55 /// is the block to branch if condition is true, operand 2 is the 56 /// condition code, and operand 3 is the flag operand produced by a CMP 57 /// instruction. 58 BR_CC, 59 60 /// SELECT_CC - Operand 0 and operand 1 are selection variable, operand 3 61 /// is condition code and operand 4 is flag operand. 62 SELECT_CC, 63 64 /// SHL, SRA, SRL - Non-constant shifts. 65 SHL, SRA, SRL 66 }; 67 } 68 69 class MSP430TargetLowering : public TargetLowering { 70 public: 71 explicit MSP430TargetLowering(const TargetMachine &TM); 72 getScalarShiftAmountTy(EVT LHSTy)73 MVT getScalarShiftAmountTy(EVT LHSTy) const override { return MVT::i8; } 74 75 /// LowerOperation - Provide custom lowering hooks for some operations. 76 SDValue LowerOperation(SDValue Op, SelectionDAG &DAG) const override; 77 78 /// getTargetNodeName - This method returns the name of a target specific 79 /// DAG node. 80 const char *getTargetNodeName(unsigned Opcode) const override; 81 82 SDValue LowerShifts(SDValue Op, SelectionDAG &DAG) const; 83 SDValue LowerGlobalAddress(SDValue Op, SelectionDAG &DAG) const; 84 SDValue LowerBlockAddress(SDValue Op, SelectionDAG &DAG) const; 85 SDValue LowerExternalSymbol(SDValue Op, SelectionDAG &DAG) const; 86 SDValue LowerBR_CC(SDValue Op, SelectionDAG &DAG) const; 87 SDValue LowerSETCC(SDValue Op, SelectionDAG &DAG) const; 88 SDValue LowerSELECT_CC(SDValue Op, SelectionDAG &DAG) const; 89 SDValue LowerSIGN_EXTEND(SDValue Op, SelectionDAG &DAG) const; 90 SDValue LowerRETURNADDR(SDValue Op, SelectionDAG &DAG) const; 91 SDValue LowerFRAMEADDR(SDValue Op, SelectionDAG &DAG) const; 92 SDValue LowerVASTART(SDValue Op, SelectionDAG &DAG) const; 93 SDValue LowerJumpTable(SDValue Op, SelectionDAG &DAG) const; 94 SDValue getReturnAddressFrameIndex(SelectionDAG &DAG) const; 95 96 TargetLowering::ConstraintType 97 getConstraintType(const std::string &Constraint) const override; 98 std::pair<unsigned, const TargetRegisterClass*> 99 getRegForInlineAsmConstraint(const std::string &Constraint, 100 MVT VT) const override; 101 102 /// isTruncateFree - Return true if it's free to truncate a value of type 103 /// Ty1 to type Ty2. e.g. On msp430 it's free to truncate a i16 value in 104 /// register R15W to i8 by referencing its sub-register R15B. 105 bool isTruncateFree(Type *Ty1, Type *Ty2) const override; 106 bool isTruncateFree(EVT VT1, EVT VT2) const override; 107 108 /// isZExtFree - Return true if any actual instruction that defines a value 109 /// of type Ty1 implicit zero-extends the value to Ty2 in the result 110 /// register. This does not necessarily include registers defined in unknown 111 /// ways, such as incoming arguments, or copies from unknown virtual 112 /// registers. Also, if isTruncateFree(Ty2, Ty1) is true, this does not 113 /// necessarily apply to truncate instructions. e.g. on msp430, all 114 /// instructions that define 8-bit values implicit zero-extend the result 115 /// out to 16 bits. 116 bool isZExtFree(Type *Ty1, Type *Ty2) const override; 117 bool isZExtFree(EVT VT1, EVT VT2) const override; 118 bool isZExtFree(SDValue Val, EVT VT2) const override; 119 120 MachineBasicBlock* EmitInstrWithCustomInserter(MachineInstr *MI, 121 MachineBasicBlock *BB) const override; 122 MachineBasicBlock* EmitShiftInstr(MachineInstr *MI, 123 MachineBasicBlock *BB) const; 124 125 private: 126 SDValue LowerCCCCallTo(SDValue Chain, SDValue Callee, 127 CallingConv::ID CallConv, bool isVarArg, 128 bool isTailCall, 129 const SmallVectorImpl<ISD::OutputArg> &Outs, 130 const SmallVectorImpl<SDValue> &OutVals, 131 const SmallVectorImpl<ISD::InputArg> &Ins, 132 SDLoc dl, SelectionDAG &DAG, 133 SmallVectorImpl<SDValue> &InVals) const; 134 135 SDValue LowerCCCArguments(SDValue Chain, 136 CallingConv::ID CallConv, 137 bool isVarArg, 138 const SmallVectorImpl<ISD::InputArg> &Ins, 139 SDLoc dl, 140 SelectionDAG &DAG, 141 SmallVectorImpl<SDValue> &InVals) const; 142 143 SDValue LowerCallResult(SDValue Chain, SDValue InFlag, 144 CallingConv::ID CallConv, bool isVarArg, 145 const SmallVectorImpl<ISD::InputArg> &Ins, 146 SDLoc dl, SelectionDAG &DAG, 147 SmallVectorImpl<SDValue> &InVals) const; 148 149 SDValue 150 LowerFormalArguments(SDValue Chain, 151 CallingConv::ID CallConv, bool isVarArg, 152 const SmallVectorImpl<ISD::InputArg> &Ins, 153 SDLoc dl, SelectionDAG &DAG, 154 SmallVectorImpl<SDValue> &InVals) const override; 155 SDValue 156 LowerCall(TargetLowering::CallLoweringInfo &CLI, 157 SmallVectorImpl<SDValue> &InVals) const override; 158 159 SDValue LowerReturn(SDValue Chain, 160 CallingConv::ID CallConv, bool isVarArg, 161 const SmallVectorImpl<ISD::OutputArg> &Outs, 162 const SmallVectorImpl<SDValue> &OutVals, 163 SDLoc dl, SelectionDAG &DAG) const override; 164 165 bool getPostIndexedAddressParts(SDNode *N, SDNode *Op, 166 SDValue &Base, 167 SDValue &Offset, 168 ISD::MemIndexedMode &AM, 169 SelectionDAG &DAG) const override; 170 }; 171 } // namespace llvm 172 173 #endif // LLVM_TARGET_MSP430_ISELLOWERING_H 174