MipsMCInstLower.cpp revision 78d1b11aa57e5a2683e4be3baaaa9576ac04eea2 
1//===-- MipsMCInstLower.cpp - Convert Mips MachineInstr to MCInst ---------===//
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 contains code to lower Mips MachineInstrs to their corresponding
11// MCInst records.
12//
13//===----------------------------------------------------------------------===//
14
15#include "MipsMCInstLower.h"
16#include "MipsAsmPrinter.h"
17#include "MipsInstrInfo.h"
18#include "MipsMCSymbolRefExpr.h"
19#include "llvm/CodeGen/MachineFunction.h"
20#include "llvm/CodeGen/MachineInstr.h"
21#include "llvm/CodeGen/MachineOperand.h"
22#include "llvm/MC/MCContext.h"
23#include "llvm/MC/MCInst.h"
24#include "llvm/Target/Mangler.h"
25using namespace llvm;
26
27MipsMCInstLower::MipsMCInstLower(Mangler *mang, const MachineFunction &mf,
28                                 MipsAsmPrinter &asmprinter)
29  : Ctx(mf.getContext()), Mang(mang), AsmPrinter(asmprinter) {}
30
31MCOperand MipsMCInstLower::LowerSymbolOperand(const MachineOperand &MO,
32                                              MachineOperandType MOTy,
33                                              unsigned Offset) const {
34  MipsMCSymbolRefExpr::VariantKind Kind;
35  const MCSymbol *Symbol;
36
37  switch(MO.getTargetFlags()) {
38  default:                  assert(0 && "Invalid target flag!");
39  case MipsII::MO_NO_FLAG:  Kind = MipsMCSymbolRefExpr::VK_Mips_None; break;
40  case MipsII::MO_GPREL:    Kind = MipsMCSymbolRefExpr::VK_Mips_GPREL; break;
41  case MipsII::MO_GOT_CALL: Kind = MipsMCSymbolRefExpr::VK_Mips_GOT_CALL; break;
42  case MipsII::MO_GOT:      Kind = MipsMCSymbolRefExpr::VK_Mips_GOT; break;
43  case MipsII::MO_ABS_HI:   Kind = MipsMCSymbolRefExpr::VK_Mips_ABS_HI; break;
44  case MipsII::MO_ABS_LO:   Kind = MipsMCSymbolRefExpr::VK_Mips_ABS_LO; break;
45  case MipsII::MO_TLSGD:    Kind = MipsMCSymbolRefExpr::VK_Mips_TLSGD; break;
46  case MipsII::MO_GOTTPREL: Kind = MipsMCSymbolRefExpr::VK_Mips_GOTTPREL; break;
47  case MipsII::MO_TPREL_HI: Kind = MipsMCSymbolRefExpr::VK_Mips_TPREL_HI; break;
48  case MipsII::MO_TPREL_LO: Kind = MipsMCSymbolRefExpr::VK_Mips_TPREL_LO; break;
49  }
50
51  switch (MOTy) {
52    case MachineOperand::MO_MachineBasicBlock:
53      Symbol = MO.getMBB()->getSymbol();
54      break;
55
56    case MachineOperand::MO_GlobalAddress:
57      Symbol = Mang->getSymbol(MO.getGlobal());
58      break;
59
60    case MachineOperand::MO_BlockAddress:
61      Symbol = AsmPrinter.GetBlockAddressSymbol(MO.getBlockAddress());
62      break;
63
64    case MachineOperand::MO_ExternalSymbol:
65      Symbol = AsmPrinter.GetExternalSymbolSymbol(MO.getSymbolName());
66      break;
67
68    case MachineOperand::MO_JumpTableIndex:
69      Symbol = AsmPrinter.GetJTISymbol(MO.getIndex());
70      break;
71
72    case MachineOperand::MO_ConstantPoolIndex:
73      Symbol = AsmPrinter.GetCPISymbol(MO.getIndex());
74      if (MO.getOffset())
75        Offset += MO.getOffset();
76      break;
77
78    default:
79      llvm_unreachable("<unknown operand type>");
80  }
81
82  return MCOperand::CreateExpr(MipsMCSymbolRefExpr::Create(Kind, Symbol, Offset,
83                                                           Ctx));
84}
85
86void MipsMCInstLower::Lower(const MachineInstr *MI, MCInst &OutMI) const {
87  OutMI.setOpcode(MI->getOpcode());
88
89  for (unsigned i = 0, e = MI->getNumOperands(); i != e; ++i) {
90    const MachineOperand &MO = MI->getOperand(i);
91    MCOperand MCOp;
92    MachineOperandType MOTy = MO.getType();
93
94    switch (MOTy) {
95    default:
96      MI->dump();
97      llvm_unreachable("unknown operand type");
98    case MachineOperand::MO_Register:
99      // Ignore all implicit register operands.
100      if (MO.isImplicit()) continue;
101      MCOp = MCOperand::CreateReg(MO.getReg());
102      break;
103    case MachineOperand::MO_Immediate:
104      MCOp = MCOperand::CreateImm(MO.getImm());
105      break;
106    case MachineOperand::MO_MachineBasicBlock:
107    case MachineOperand::MO_GlobalAddress:
108    case MachineOperand::MO_ExternalSymbol:
109    case MachineOperand::MO_JumpTableIndex:
110    case MachineOperand::MO_ConstantPoolIndex:
111    case MachineOperand::MO_BlockAddress:
112      MCOp = LowerSymbolOperand(MO, MOTy, 0);
113      break;
114    }
115
116    OutMI.addOperand(MCOp);
117  }
118}
119