lib/Target/Mips/MipsMCInstLower.cpp

   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"
  25 using namespace llvm;
  26
  27 MipsMCInstLower::MipsMCInstLower(Mangler *mang, const MachineFunction &mf,
  28                                  MipsAsmPrinter &asmprinter)
  29   : Ctx(mf.getContext()), Mang(mang), AsmPrinter(asmprinter) {}
  30
  31 MCOperand MipsMCInstLower::LowerSymbolOperand(const MachineOperand &MO,
  32                                               MachineOperandType MOTy) const {
  33   MipsMCSymbolRefExpr::VariantKind Kind;
  34   const MCSymbol *Symbol;
  35   int Offset = 0;
  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
  86 void 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);
 113       break;
 114     }
 115
 116     OutMI.addOperand(MCOp);
 117   }
 118 }