InstrEmitter.h revision 17b0c672b8e2eec92c19b81fa192a5d74ebfdfe0
1//===---- InstrEmitter.h - Emit MachineInstrs for the SelectionDAG class ---==// 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 declares the Emit routines for the SelectionDAG class, which creates 11// MachineInstrs based on the decisions of the SelectionDAG instruction 12// selection. 13// 14//===----------------------------------------------------------------------===// 15 16#ifndef INSTREMITTER_H 17#define INSTREMITTER_H 18 19#include "llvm/CodeGen/SelectionDAG.h" 20#include "llvm/CodeGen/MachineBasicBlock.h" 21#include "llvm/ADT/DenseMap.h" 22 23namespace llvm { 24 25class TargetInstrDesc; 26class SDDbgValue; 27 28class InstrEmitter { 29 MachineFunction *MF; 30 MachineRegisterInfo *MRI; 31 const TargetMachine *TM; 32 const TargetInstrInfo *TII; 33 const TargetRegisterInfo *TRI; 34 const TargetLowering *TLI; 35 36 MachineBasicBlock *MBB; 37 MachineBasicBlock::iterator InsertPos; 38 39 /// EmitCopyFromReg - Generate machine code for an CopyFromReg node or an 40 /// implicit physical register output. 41 void EmitCopyFromReg(SDNode *Node, unsigned ResNo, 42 bool IsClone, bool IsCloned, 43 unsigned SrcReg, 44 DenseMap<SDValue, unsigned> &VRBaseMap); 45 46 /// getDstOfCopyToRegUse - If the only use of the specified result number of 47 /// node is a CopyToReg, return its destination register. Return 0 otherwise. 48 unsigned getDstOfOnlyCopyToRegUse(SDNode *Node, 49 unsigned ResNo) const; 50 51 void CreateVirtualRegisters(SDNode *Node, MachineInstr *MI, 52 const TargetInstrDesc &II, 53 bool IsClone, bool IsCloned, 54 DenseMap<SDValue, unsigned> &VRBaseMap); 55 56 /// getVR - Return the virtual register corresponding to the specified result 57 /// of the specified node. 58 unsigned getVR(SDValue Op, 59 DenseMap<SDValue, unsigned> &VRBaseMap); 60 61 /// AddRegisterOperand - Add the specified register as an operand to the 62 /// specified machine instr. Insert register copies if the register is 63 /// not in the required register class. 64 void AddRegisterOperand(MachineInstr *MI, SDValue Op, 65 unsigned IIOpNum, 66 const TargetInstrDesc *II, 67 DenseMap<SDValue, unsigned> &VRBaseMap, 68 bool IsDebug = false); 69 70 /// AddOperand - Add the specified operand to the specified machine instr. II 71 /// specifies the instruction information for the node, and IIOpNum is the 72 /// operand number (in the II) that we are adding. IIOpNum and II are used for 73 /// assertions only. 74 void AddOperand(MachineInstr *MI, SDValue Op, 75 unsigned IIOpNum, 76 const TargetInstrDesc *II, 77 DenseMap<SDValue, unsigned> &VRBaseMap, 78 bool IsDebug = false); 79 80 /// EmitSubregNode - Generate machine code for subreg nodes. 81 /// 82 void EmitSubregNode(SDNode *Node, DenseMap<SDValue, unsigned> &VRBaseMap); 83 84 /// EmitCopyToRegClassNode - Generate machine code for COPY_TO_REGCLASS nodes. 85 /// COPY_TO_REGCLASS is just a normal copy, except that the destination 86 /// register is constrained to be in a particular register class. 87 /// 88 void EmitCopyToRegClassNode(SDNode *Node, 89 DenseMap<SDValue, unsigned> &VRBaseMap); 90 91public: 92 /// CountResults - The results of target nodes have register or immediate 93 /// operands first, then an optional chain, and optional flag operands 94 /// (which do not go into the machine instrs.) 95 static unsigned CountResults(SDNode *Node); 96 97 /// CountOperands - The inputs to target nodes have any actual inputs first, 98 /// followed by an optional chain operand, then flag operands. Compute 99 /// the number of actual operands that will go into the resulting 100 /// MachineInstr. 101 static unsigned CountOperands(SDNode *Node); 102 103 /// EmitDbgValue - Generate machine instruction for a dbg_value node. 104 /// 105 MachineInstr *EmitDbgValue(SDDbgValue *SD, 106 DenseMap<SDValue, unsigned> &VRBaseMap, 107 DenseMap<MachineBasicBlock*, MachineBasicBlock*> *EM); 108 109 /// EmitNode - Generate machine code for a node and needed dependencies. 110 /// 111 void EmitNode(SDNode *Node, bool IsClone, bool IsCloned, 112 DenseMap<SDValue, unsigned> &VRBaseMap, 113 DenseMap<MachineBasicBlock*, MachineBasicBlock*> *EM) { 114 if (Node->isMachineOpcode()) 115 EmitMachineNode(Node, IsClone, IsCloned, VRBaseMap, EM); 116 else 117 EmitSpecialNode(Node, IsClone, IsCloned, VRBaseMap); 118 } 119 120 /// getBlock - Return the current basic block. 121 MachineBasicBlock *getBlock() { return MBB; } 122 123 /// getInsertPos - Return the current insertion position. 124 MachineBasicBlock::iterator getInsertPos() { return InsertPos; } 125 126 /// InstrEmitter - Construct an InstrEmitter and set it to start inserting 127 /// at the given position in the given block. 128 InstrEmitter(MachineBasicBlock *mbb, MachineBasicBlock::iterator insertpos); 129 130private: 131 void EmitMachineNode(SDNode *Node, bool IsClone, bool IsCloned, 132 DenseMap<SDValue, unsigned> &VRBaseMap, 133 DenseMap<MachineBasicBlock*, MachineBasicBlock*> *EM); 134 void EmitSpecialNode(SDNode *Node, bool IsClone, bool IsCloned, 135 DenseMap<SDValue, unsigned> &VRBaseMap); 136}; 137 138} 139 140#endif 141