aboutsummaryrefslogtreecommitdiffstats
path: root/lib/Target/PowerPC/PPCMCInstLower.cpp
blob: 819738b206245fbf7ba7b2b3d56fc1ddbd2680c0 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
//===-- PPCMCInstLower.cpp - Convert PPC MachineInstr to an MCInst --------===//
//
//                     The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file contains code to lower PPC MachineInstrs to their corresponding
// MCInst records.
//
//===----------------------------------------------------------------------===//

#include "PPC.h"
#include "MCTargetDesc/PPCMCExpr.h"
#include "PPCSubtarget.h"
#include "llvm/ADT/SmallString.h"
#include "llvm/ADT/Twine.h"
#include "llvm/CodeGen/AsmPrinter.h"
#include "llvm/CodeGen/MachineFunction.h"
#include "llvm/CodeGen/MachineModuleInfoImpls.h"
#include "llvm/IR/DataLayout.h"
#include "llvm/IR/GlobalValue.h"
#include "llvm/IR/Mangler.h"
#include "llvm/MC/MCAsmInfo.h"
#include "llvm/MC/MCExpr.h"
#include "llvm/MC/MCInst.h"
#include "llvm/Target/TargetLowering.h"
#include "llvm/Target/TargetLoweringObjectFile.h"
using namespace llvm;

static MachineModuleInfoMachO &getMachOMMI(AsmPrinter &AP) {
  return AP.MMI->getObjFileInfo<MachineModuleInfoMachO>();
}


static MCSymbol *GetSymbolFromOperand(const MachineOperand &MO, AsmPrinter &AP){
  const TargetMachine &TM = AP.TM;
  Mangler *Mang = AP.Mang;
  const DataLayout *DL = TM.getDataLayout();
  MCContext &Ctx = AP.OutContext;
  bool isDarwin = Triple(TM.getTargetTriple()).isOSDarwin();

  SmallString<128> Name;
  StringRef Suffix;
  if (MO.getTargetFlags() == PPCII::MO_PLT_OR_STUB) {
    if (isDarwin)
      Suffix = "$stub";
  } else if (MO.getTargetFlags() & PPCII::MO_NLP_FLAG)
    Suffix = "$non_lazy_ptr";

  if (!Suffix.empty())
    Name += DL->getPrivateGlobalPrefix();

  unsigned PrefixLen = Name.size();

  if (!MO.isGlobal()) {
    assert(MO.isSymbol() && "Isn't a symbol reference");
    Mang->getNameWithPrefix(Name, MO.getSymbolName());
  } else {
    const GlobalValue *GV = MO.getGlobal();
    TM.getNameWithPrefix(Name, GV, *Mang);
  }

  unsigned OrigLen = Name.size() - PrefixLen;

  Name += Suffix;
  MCSymbol *Sym = Ctx.GetOrCreateSymbol(Name.str());
  StringRef OrigName = StringRef(Name).substr(PrefixLen, OrigLen);

  // If the target flags on the operand changes the name of the symbol, do that
  // before we return the symbol.
  if (MO.getTargetFlags() == PPCII::MO_PLT_OR_STUB && isDarwin) {
    MachineModuleInfoImpl::StubValueTy &StubSym =
      getMachOMMI(AP).getFnStubEntry(Sym);
    if (StubSym.getPointer())
      return Sym;
    
    if (MO.isGlobal()) {
      StubSym =
      MachineModuleInfoImpl::
      StubValueTy(AP.getSymbol(MO.getGlobal()),
                  !MO.getGlobal()->hasInternalLinkage());
    } else {
      StubSym =
      MachineModuleInfoImpl::
      StubValueTy(Ctx.GetOrCreateSymbol(OrigName), false);
    }
    return Sym;
  }

  // If the symbol reference is actually to a non_lazy_ptr, not to the symbol,
  // then add the suffix.
  if (MO.getTargetFlags() & PPCII::MO_NLP_FLAG) {
    MachineModuleInfoMachO &MachO = getMachOMMI(AP);
    
    MachineModuleInfoImpl::StubValueTy &StubSym =
      (MO.getTargetFlags() & PPCII::MO_NLP_HIDDEN_FLAG) ? 
         MachO.getHiddenGVStubEntry(Sym) : MachO.getGVStubEntry(Sym);
    
    if (!StubSym.getPointer()) {
      assert(MO.isGlobal() && "Extern symbol not handled yet");
      StubSym = MachineModuleInfoImpl::
                   StubValueTy(AP.getSymbol(MO.getGlobal()),
                               !MO.getGlobal()->hasInternalLinkage());
    }
    return Sym;
  }
  
  return Sym;
}

static MCOperand GetSymbolRef(const MachineOperand &MO, const MCSymbol *Symbol,
                              AsmPrinter &Printer, bool isDarwin) {
  MCContext &Ctx = Printer.OutContext;
  MCSymbolRefExpr::VariantKind RefKind = MCSymbolRefExpr::VK_None;

  unsigned access = MO.getTargetFlags() & PPCII::MO_ACCESS_MASK;

  switch (access) {
    case PPCII::MO_TPREL_LO:
      RefKind = MCSymbolRefExpr::VK_PPC_TPREL_LO;
      break;
    case PPCII::MO_TPREL_HA:
      RefKind = MCSymbolRefExpr::VK_PPC_TPREL_HA;
      break;
    case PPCII::MO_DTPREL_LO:
      RefKind = MCSymbolRefExpr::VK_PPC_DTPREL_LO;
      break;
    case PPCII::MO_TLSLD_LO:
      RefKind = MCSymbolRefExpr::VK_PPC_GOT_TLSLD_LO;
      break;
    case PPCII::MO_TOC_LO:
      RefKind = MCSymbolRefExpr::VK_PPC_TOC_LO;
      break;
    case PPCII::MO_TLS:
      RefKind = MCSymbolRefExpr::VK_PPC_TLS;
      break;
  }

  if (MO.getTargetFlags() == PPCII::MO_PLT_OR_STUB && !isDarwin)
    RefKind = MCSymbolRefExpr::VK_PLT;

  const MCExpr *Expr = MCSymbolRefExpr::Create(Symbol, RefKind, Ctx);

  if (!MO.isJTI() && MO.getOffset())
    Expr = MCBinaryExpr::CreateAdd(Expr,
                                   MCConstantExpr::Create(MO.getOffset(), Ctx),
                                   Ctx);

  // Subtract off the PIC base if required.
  if (MO.getTargetFlags() & PPCII::MO_PIC_FLAG) {
    const MachineFunction *MF = MO.getParent()->getParent()->getParent();
    
    const MCExpr *PB = MCSymbolRefExpr::Create(MF->getPICBaseSymbol(), Ctx);
    Expr = MCBinaryExpr::CreateSub(Expr, PB, Ctx);
  }

  // Add ha16() / lo16() markers if required.
  switch (access) {
    case PPCII::MO_LO:
      Expr = PPCMCExpr::CreateLo(Expr, isDarwin, Ctx);
      break;
    case PPCII::MO_HA:
      Expr = PPCMCExpr::CreateHa(Expr, isDarwin, Ctx);
      break;
  }

  return MCOperand::CreateExpr(Expr);
}

void llvm::LowerPPCMachineInstrToMCInst(const MachineInstr *MI, MCInst &OutMI,
                                        AsmPrinter &AP, bool isDarwin) {
  OutMI.setOpcode(MI->getOpcode());
  
  for (unsigned i = 0, e = MI->getNumOperands(); i != e; ++i) {
    const MachineOperand &MO = MI->getOperand(i);
    
    MCOperand MCOp;
    switch (MO.getType()) {
    default:
      MI->dump();
      llvm_unreachable("unknown operand type");
    case MachineOperand::MO_Register:
      assert(!MO.getSubReg() && "Subregs should be eliminated!");
      MCOp = MCOperand::CreateReg(MO.getReg());
      break;
    case MachineOperand::MO_Immediate:
      MCOp = MCOperand::CreateImm(MO.getImm());
      break;
    case MachineOperand::MO_MachineBasicBlock:
      MCOp = MCOperand::CreateExpr(MCSymbolRefExpr::Create(
                                      MO.getMBB()->getSymbol(), AP.OutContext));
      break;
    case MachineOperand::MO_GlobalAddress:
    case MachineOperand::MO_ExternalSymbol:
      MCOp = GetSymbolRef(MO, GetSymbolFromOperand(MO, AP), AP, isDarwin);
      break;
    case MachineOperand::MO_JumpTableIndex:
      MCOp = GetSymbolRef(MO, AP.GetJTISymbol(MO.getIndex()), AP, isDarwin);
      break;
    case MachineOperand::MO_ConstantPoolIndex:
      MCOp = GetSymbolRef(MO, AP.GetCPISymbol(MO.getIndex()), AP, isDarwin);
      break;
    case MachineOperand::MO_BlockAddress:
      MCOp = GetSymbolRef(MO,AP.GetBlockAddressSymbol(MO.getBlockAddress()),AP,
                          isDarwin);
      break;
    case MachineOperand::MO_RegisterMask:
      continue;
    }
    
    OutMI.addOperand(MCOp);
  }
}