1 //===-- PPCMCInstLower.cpp - Convert PPC MachineInstr to an 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 PPC MachineInstrs to their corresponding
11 // MCInst records.
12 //
13 //===----------------------------------------------------------------------===//
14
15 #include "PPC.h"
16 #include "MCTargetDesc/PPCMCExpr.h"
17 #include "llvm/ADT/SmallString.h"
18 #include "llvm/ADT/Twine.h"
19 #include "llvm/CodeGen/AsmPrinter.h"
20 #include "llvm/CodeGen/MachineFunction.h"
21 #include "llvm/CodeGen/MachineModuleInfoImpls.h"
22 #include "llvm/IR/DataLayout.h"
23 #include "llvm/IR/GlobalValue.h"
24 #include "llvm/IR/Mangler.h"
25 #include "llvm/MC/MCAsmInfo.h"
26 #include "llvm/MC/MCExpr.h"
27 #include "llvm/MC/MCInst.h"
28 #include "llvm/Target/TargetLowering.h"
29 #include "llvm/Target/TargetLoweringObjectFile.h"
30 using namespace llvm;
31
getMachOMMI(AsmPrinter & AP)32 static MachineModuleInfoMachO &getMachOMMI(AsmPrinter &AP) {
33 return AP.MMI->getObjFileInfo<MachineModuleInfoMachO>();
34 }
35
36
GetSymbolFromOperand(const MachineOperand & MO,AsmPrinter & AP)37 static MCSymbol *GetSymbolFromOperand(const MachineOperand &MO, AsmPrinter &AP){
38 const TargetMachine &TM = AP.TM;
39 Mangler *Mang = AP.Mang;
40 const DataLayout *DL = TM.getDataLayout();
41 MCContext &Ctx = AP.OutContext;
42
43 SmallString<128> Name;
44 StringRef Suffix;
45 if (MO.getTargetFlags() == PPCII::MO_DARWIN_STUB)
46 Suffix = "$stub";
47 else if (MO.getTargetFlags() & PPCII::MO_NLP_FLAG)
48 Suffix = "$non_lazy_ptr";
49
50 if (!Suffix.empty())
51 Name += DL->getPrivateGlobalPrefix();
52
53 unsigned PrefixLen = Name.size();
54
55 if (!MO.isGlobal()) {
56 assert(MO.isSymbol() && "Isn't a symbol reference");
57 Mang->getNameWithPrefix(Name, MO.getSymbolName());
58 } else {
59 const GlobalValue *GV = MO.getGlobal();
60 TM.getNameWithPrefix(Name, GV, *Mang);
61 }
62
63 unsigned OrigLen = Name.size() - PrefixLen;
64
65 Name += Suffix;
66 MCSymbol *Sym = Ctx.GetOrCreateSymbol(Name.str());
67 StringRef OrigName = StringRef(Name).substr(PrefixLen, OrigLen);
68
69 // If the target flags on the operand changes the name of the symbol, do that
70 // before we return the symbol.
71 if (MO.getTargetFlags() == PPCII::MO_DARWIN_STUB) {
72 MachineModuleInfoImpl::StubValueTy &StubSym =
73 getMachOMMI(AP).getFnStubEntry(Sym);
74 if (StubSym.getPointer())
75 return Sym;
76
77 if (MO.isGlobal()) {
78 StubSym =
79 MachineModuleInfoImpl::
80 StubValueTy(AP.getSymbol(MO.getGlobal()),
81 !MO.getGlobal()->hasInternalLinkage());
82 } else {
83 StubSym =
84 MachineModuleInfoImpl::
85 StubValueTy(Ctx.GetOrCreateSymbol(OrigName), false);
86 }
87 return Sym;
88 }
89
90 // If the symbol reference is actually to a non_lazy_ptr, not to the symbol,
91 // then add the suffix.
92 if (MO.getTargetFlags() & PPCII::MO_NLP_FLAG) {
93 MachineModuleInfoMachO &MachO = getMachOMMI(AP);
94
95 MachineModuleInfoImpl::StubValueTy &StubSym =
96 (MO.getTargetFlags() & PPCII::MO_NLP_HIDDEN_FLAG) ?
97 MachO.getHiddenGVStubEntry(Sym) : MachO.getGVStubEntry(Sym);
98
99 if (!StubSym.getPointer()) {
100 assert(MO.isGlobal() && "Extern symbol not handled yet");
101 StubSym = MachineModuleInfoImpl::
102 StubValueTy(AP.getSymbol(MO.getGlobal()),
103 !MO.getGlobal()->hasInternalLinkage());
104 }
105 return Sym;
106 }
107
108 return Sym;
109 }
110
GetSymbolRef(const MachineOperand & MO,const MCSymbol * Symbol,AsmPrinter & Printer,bool isDarwin)111 static MCOperand GetSymbolRef(const MachineOperand &MO, const MCSymbol *Symbol,
112 AsmPrinter &Printer, bool isDarwin) {
113 MCContext &Ctx = Printer.OutContext;
114 MCSymbolRefExpr::VariantKind RefKind = MCSymbolRefExpr::VK_None;
115
116 unsigned access = MO.getTargetFlags() & PPCII::MO_ACCESS_MASK;
117
118 switch (access) {
119 case PPCII::MO_TPREL_LO:
120 RefKind = MCSymbolRefExpr::VK_PPC_TPREL_LO;
121 break;
122 case PPCII::MO_TPREL_HA:
123 RefKind = MCSymbolRefExpr::VK_PPC_TPREL_HA;
124 break;
125 case PPCII::MO_DTPREL_LO:
126 RefKind = MCSymbolRefExpr::VK_PPC_DTPREL_LO;
127 break;
128 case PPCII::MO_TLSLD_LO:
129 RefKind = MCSymbolRefExpr::VK_PPC_GOT_TLSLD_LO;
130 break;
131 case PPCII::MO_TOC_LO:
132 RefKind = MCSymbolRefExpr::VK_PPC_TOC_LO;
133 break;
134 case PPCII::MO_TLS:
135 RefKind = MCSymbolRefExpr::VK_PPC_TLS;
136 break;
137 }
138
139 const MCExpr *Expr = MCSymbolRefExpr::Create(Symbol, RefKind, Ctx);
140
141 if (!MO.isJTI() && MO.getOffset())
142 Expr = MCBinaryExpr::CreateAdd(Expr,
143 MCConstantExpr::Create(MO.getOffset(), Ctx),
144 Ctx);
145
146 // Subtract off the PIC base if required.
147 if (MO.getTargetFlags() & PPCII::MO_PIC_FLAG) {
148 const MachineFunction *MF = MO.getParent()->getParent()->getParent();
149
150 const MCExpr *PB = MCSymbolRefExpr::Create(MF->getPICBaseSymbol(), Ctx);
151 Expr = MCBinaryExpr::CreateSub(Expr, PB, Ctx);
152 }
153
154 // Add ha16() / lo16() markers if required.
155 switch (access) {
156 case PPCII::MO_LO:
157 Expr = PPCMCExpr::CreateLo(Expr, isDarwin, Ctx);
158 break;
159 case PPCII::MO_HA:
160 Expr = PPCMCExpr::CreateHa(Expr, isDarwin, Ctx);
161 break;
162 }
163
164 return MCOperand::CreateExpr(Expr);
165 }
166
LowerPPCMachineInstrToMCInst(const MachineInstr * MI,MCInst & OutMI,AsmPrinter & AP,bool isDarwin)167 void llvm::LowerPPCMachineInstrToMCInst(const MachineInstr *MI, MCInst &OutMI,
168 AsmPrinter &AP, bool isDarwin) {
169 OutMI.setOpcode(MI->getOpcode());
170
171 for (unsigned i = 0, e = MI->getNumOperands(); i != e; ++i) {
172 const MachineOperand &MO = MI->getOperand(i);
173
174 MCOperand MCOp;
175 switch (MO.getType()) {
176 default:
177 MI->dump();
178 llvm_unreachable("unknown operand type");
179 case MachineOperand::MO_Register:
180 assert(!MO.getSubReg() && "Subregs should be eliminated!");
181 MCOp = MCOperand::CreateReg(MO.getReg());
182 break;
183 case MachineOperand::MO_Immediate:
184 MCOp = MCOperand::CreateImm(MO.getImm());
185 break;
186 case MachineOperand::MO_MachineBasicBlock:
187 MCOp = MCOperand::CreateExpr(MCSymbolRefExpr::Create(
188 MO.getMBB()->getSymbol(), AP.OutContext));
189 break;
190 case MachineOperand::MO_GlobalAddress:
191 case MachineOperand::MO_ExternalSymbol:
192 MCOp = GetSymbolRef(MO, GetSymbolFromOperand(MO, AP), AP, isDarwin);
193 break;
194 case MachineOperand::MO_JumpTableIndex:
195 MCOp = GetSymbolRef(MO, AP.GetJTISymbol(MO.getIndex()), AP, isDarwin);
196 break;
197 case MachineOperand::MO_ConstantPoolIndex:
198 MCOp = GetSymbolRef(MO, AP.GetCPISymbol(MO.getIndex()), AP, isDarwin);
199 break;
200 case MachineOperand::MO_BlockAddress:
201 MCOp = GetSymbolRef(MO,AP.GetBlockAddressSymbol(MO.getBlockAddress()),AP,
202 isDarwin);
203 break;
204 case MachineOperand::MO_RegisterMask:
205 continue;
206 }
207
208 OutMI.addOperand(MCOp);
209 }
210 }
211