MachineInstrBuilder.h revision 9cc361579b6a0aad9a71dc617eedd4d909d48acf 
1//===-- CodeGen/MachineInstBuilder.h - Simplify creation of MIs -*- C++ -*-===//
2//
3// This file exposes a function named BuildMI, which is useful for dramatically
4// simplifying how MachineInstr's are created.  Instead of using code like this:
5//
6//   M = new MachineInstr(X86::ADDrr32);
7//   M->SetMachineOperandVal(0, MachineOperand::MO_VirtualRegister, argVal1);
8//   M->SetMachineOperandVal(1, MachineOperand::MO_VirtualRegister, argVal2);
9//
10// we can now use code like this:
11//
12//   M = BuildMI(X86::ADDrr8, 2).addReg(argVal1).addReg(argVal2);
13//
14//===----------------------------------------------------------------------===//
15
16#ifndef LLVM_CODEGEN_MACHINEINSTRBUILDER_H
17#define LLVM_CODEGEN_MACHINEINSTRBUILDER_H
18
19#include "llvm/CodeGen/MachineInstr.h"
20
21struct MachineInstrBuilder {
22  MachineInstr *MI;
23
24  MachineInstrBuilder(MachineInstr *mi) : MI(mi) {}
25
26  /// Allow automatic conversion to the machine instruction we are working on.
27  ///
28  operator MachineInstr*() const { return MI; }
29
30  /// addReg - Add a new virtual register operand...
31  ///
32  MachineInstrBuilder &addReg(int RegNo, bool isDef = false) {
33    MI->addRegOperand(RegNo, isDef);
34    return *this;
35  }
36
37  /// addReg - Add an LLVM value that is to be used as a register...x
38  ///
39  MachineInstrBuilder &addReg(Value *V, bool isDef = false, bool isDNU = false){
40    MI->addRegOperand(V, isDef, isDNU);
41    return *this;
42  }
43
44  /// addPCDisp - Add an LLVM value to be treated as a PC relative
45  /// displacement...
46  ///
47  MachineInstrBuilder &addPCDisp(Value *V) {
48    MI->addPCDispOperand(V);
49    return *this;
50  }
51
52  /// addMReg - Add a machine register operand...
53  ///
54  MachineInstrBuilder &addMReg(int Reg, bool isDef=false) {
55    MI->addMachineRegOperand(Reg, isDef);
56    return *this;
57  }
58
59  /// addSImm - Add a new sign extended immediate operand...
60  ///
61  MachineInstrBuilder &addSImm(int64_t val) {
62    MI->addSignExtImmOperand(val);
63    return *this;
64  }
65
66  /// addZImm - Add a new zero extended immediate operand...
67  ///
68  MachineInstrBuilder &addZImm(int64_t Val) {
69    MI->addZeroExtImmOperand(Val);
70    return *this;
71  }
72};
73
74/// BuildMI - Builder interface.  Specify how to create the initial instruction
75/// itself.  NumOperands is the number of operands to the machine instruction to
76/// allow for memory efficient representation of machine instructions.
77///
78inline MachineInstrBuilder BuildMI(MachineOpCode Opcode, unsigned NumOperands) {
79  return MachineInstrBuilder(new MachineInstr(Opcode, NumOperands, true, true));
80}
81
82/// BuildMI - This version of the builder inserts the built MachineInstr into
83/// the specified MachineBasicBlock.
84///
85inline MachineInstrBuilder BuildMI(MachineBasicBlock *BB, MachineOpCode Opcode,
86                                   unsigned NumOperands) {
87  return MachineInstrBuilder(new MachineInstr(BB, Opcode, NumOperands));
88}
89
90/// BuildMI - This version of the builder inserts the built MachineInstr into
91/// the specified MachineBasicBlock, and also sets up the first "operand" as a
92/// destination virtual register.  NumOperands is the number of additional add*
93/// calls that are expected, it does not include the destination register.
94///
95inline MachineInstrBuilder BuildMI(MachineBasicBlock *BB, MachineOpCode Opcode,
96                                   unsigned NumOperands, unsigned DestReg) {
97  return MachineInstrBuilder(new MachineInstr(BB, Opcode,
98                                              NumOperands+1)).addReg(DestReg,
99                                                                     true);
100}
101
102#endif
103