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 "PPCSubtarget.h"
18 #include "llvm/ADT/SmallString.h"
19 #include "llvm/ADT/Twine.h"
20 #include "llvm/CodeGen/AsmPrinter.h"
21 #include "llvm/CodeGen/MachineFunction.h"
22 #include "llvm/CodeGen/MachineModuleInfoImpls.h"
23 #include "llvm/IR/DataLayout.h"
24 #include "llvm/IR/GlobalValue.h"
25 #include "llvm/IR/Mangler.h"
26 #include "llvm/MC/MCAsmInfo.h"
27 #include "llvm/MC/MCExpr.h"
28 #include "llvm/MC/MCInst.h"
29 #include "llvm/Target/TargetLowering.h"
30 #include "llvm/Target/TargetLoweringObjectFile.h"
31 using namespace llvm;
32
getMachOMMI(AsmPrinter & AP)33 static MachineModuleInfoMachO &getMachOMMI(AsmPrinter &AP) {
34 return AP.MMI->getObjFileInfo<MachineModuleInfoMachO>();
35 }
36
37
GetSymbolFromOperand(const MachineOperand & MO,AsmPrinter & AP)38 static MCSymbol *GetSymbolFromOperand(const MachineOperand &MO, AsmPrinter &AP){
39 const TargetMachine &TM = AP.TM;
40 Mangler *Mang = AP.Mang;
41 const DataLayout &DL = AP.getDataLayout();
42 MCContext &Ctx = AP.OutContext;
43 bool isDarwin = TM.getTargetTriple().isOSDarwin();
44
45 SmallString<128> Name;
46 StringRef Suffix;
47 if (MO.getTargetFlags() == PPCII::MO_PLT_OR_STUB) {
48 if (isDarwin)
49 Suffix = "$stub";
50 } else if (MO.getTargetFlags() & PPCII::MO_NLP_FLAG)
51 Suffix = "$non_lazy_ptr";
52
53 if (!Suffix.empty())
54 Name += DL.getPrivateGlobalPrefix();
55
56 unsigned PrefixLen = Name.size();
57
58 if (!MO.isGlobal()) {
59 assert(MO.isSymbol() && "Isn't a symbol reference");
60 Mangler::getNameWithPrefix(Name, MO.getSymbolName(), DL);
61 } else {
62 const GlobalValue *GV = MO.getGlobal();
63 TM.getNameWithPrefix(Name, GV, *Mang);
64 }
65
66 unsigned OrigLen = Name.size() - PrefixLen;
67
68 Name += Suffix;
69 MCSymbol *Sym = Ctx.getOrCreateSymbol(Name);
70 StringRef OrigName = StringRef(Name).substr(PrefixLen, OrigLen);
71
72 // If the target flags on the operand changes the name of the symbol, do that
73 // before we return the symbol.
74 if (MO.getTargetFlags() == PPCII::MO_PLT_OR_STUB && isDarwin) {
75 MachineModuleInfoImpl::StubValueTy &StubSym =
76 getMachOMMI(AP).getFnStubEntry(Sym);
77 if (StubSym.getPointer())
78 return Sym;
79
80 if (MO.isGlobal()) {
81 StubSym =
82 MachineModuleInfoImpl::
83 StubValueTy(AP.getSymbol(MO.getGlobal()),
84 !MO.getGlobal()->hasInternalLinkage());
85 } else {
86 StubSym =
87 MachineModuleInfoImpl::
88 StubValueTy(Ctx.getOrCreateSymbol(OrigName), false);
89 }
90 return Sym;
91 }
92
93 // If the symbol reference is actually to a non_lazy_ptr, not to the symbol,
94 // then add the suffix.
95 if (MO.getTargetFlags() & PPCII::MO_NLP_FLAG) {
96 MachineModuleInfoMachO &MachO = getMachOMMI(AP);
97
98 MachineModuleInfoImpl::StubValueTy &StubSym =
99 (MO.getTargetFlags() & PPCII::MO_NLP_HIDDEN_FLAG) ?
100 MachO.getHiddenGVStubEntry(Sym) : MachO.getGVStubEntry(Sym);
101
102 if (!StubSym.getPointer()) {
103 assert(MO.isGlobal() && "Extern symbol not handled yet");
104 StubSym = MachineModuleInfoImpl::
105 StubValueTy(AP.getSymbol(MO.getGlobal()),
106 !MO.getGlobal()->hasInternalLinkage());
107 }
108 return Sym;
109 }
110
111 return Sym;
112 }
113
GetSymbolRef(const MachineOperand & MO,const MCSymbol * Symbol,AsmPrinter & Printer,bool isDarwin)114 static MCOperand GetSymbolRef(const MachineOperand &MO, const MCSymbol *Symbol,
115 AsmPrinter &Printer, bool isDarwin) {
116 MCContext &Ctx = Printer.OutContext;
117 MCSymbolRefExpr::VariantKind RefKind = MCSymbolRefExpr::VK_None;
118
119 unsigned access = MO.getTargetFlags() & PPCII::MO_ACCESS_MASK;
120
121 switch (access) {
122 case PPCII::MO_TPREL_LO:
123 RefKind = MCSymbolRefExpr::VK_PPC_TPREL_LO;
124 break;
125 case PPCII::MO_TPREL_HA:
126 RefKind = MCSymbolRefExpr::VK_PPC_TPREL_HA;
127 break;
128 case PPCII::MO_DTPREL_LO:
129 RefKind = MCSymbolRefExpr::VK_PPC_DTPREL_LO;
130 break;
131 case PPCII::MO_TLSLD_LO:
132 RefKind = MCSymbolRefExpr::VK_PPC_GOT_TLSLD_LO;
133 break;
134 case PPCII::MO_TOC_LO:
135 RefKind = MCSymbolRefExpr::VK_PPC_TOC_LO;
136 break;
137 case PPCII::MO_TLS:
138 RefKind = MCSymbolRefExpr::VK_PPC_TLS;
139 break;
140 }
141
142 if (MO.getTargetFlags() == PPCII::MO_PLT_OR_STUB && !isDarwin)
143 RefKind = MCSymbolRefExpr::VK_PLT;
144
145 const MCExpr *Expr = MCSymbolRefExpr::create(Symbol, RefKind, Ctx);
146
147 if (!MO.isJTI() && MO.getOffset())
148 Expr = MCBinaryExpr::createAdd(Expr,
149 MCConstantExpr::create(MO.getOffset(), Ctx),
150 Ctx);
151
152 // Subtract off the PIC base if required.
153 if (MO.getTargetFlags() & PPCII::MO_PIC_FLAG) {
154 const MachineFunction *MF = MO.getParent()->getParent()->getParent();
155
156 const MCExpr *PB = MCSymbolRefExpr::create(MF->getPICBaseSymbol(), Ctx);
157 Expr = MCBinaryExpr::createSub(Expr, PB, Ctx);
158 }
159
160 // Add ha16() / lo16() markers if required.
161 switch (access) {
162 case PPCII::MO_LO:
163 Expr = PPCMCExpr::createLo(Expr, isDarwin, Ctx);
164 break;
165 case PPCII::MO_HA:
166 Expr = PPCMCExpr::createHa(Expr, isDarwin, Ctx);
167 break;
168 }
169
170 return MCOperand::createExpr(Expr);
171 }
172
LowerPPCMachineInstrToMCInst(const MachineInstr * MI,MCInst & OutMI,AsmPrinter & AP,bool isDarwin)173 void llvm::LowerPPCMachineInstrToMCInst(const MachineInstr *MI, MCInst &OutMI,
174 AsmPrinter &AP, bool isDarwin) {
175 OutMI.setOpcode(MI->getOpcode());
176
177 for (unsigned i = 0, e = MI->getNumOperands(); i != e; ++i) {
178 const MachineOperand &MO = MI->getOperand(i);
179
180 MCOperand MCOp;
181 switch (MO.getType()) {
182 default:
183 MI->dump();
184 llvm_unreachable("unknown operand type");
185 case MachineOperand::MO_Register:
186 assert(!MO.getSubReg() && "Subregs should be eliminated!");
187 assert(MO.getReg() > PPC::NoRegister &&
188 MO.getReg() < PPC::NUM_TARGET_REGS &&
189 "Invalid register for this target!");
190 MCOp = MCOperand::createReg(MO.getReg());
191 break;
192 case MachineOperand::MO_Immediate:
193 MCOp = MCOperand::createImm(MO.getImm());
194 break;
195 case MachineOperand::MO_MachineBasicBlock:
196 MCOp = MCOperand::createExpr(MCSymbolRefExpr::create(
197 MO.getMBB()->getSymbol(), AP.OutContext));
198 break;
199 case MachineOperand::MO_GlobalAddress:
200 case MachineOperand::MO_ExternalSymbol:
201 MCOp = GetSymbolRef(MO, GetSymbolFromOperand(MO, AP), AP, isDarwin);
202 break;
203 case MachineOperand::MO_JumpTableIndex:
204 MCOp = GetSymbolRef(MO, AP.GetJTISymbol(MO.getIndex()), AP, isDarwin);
205 break;
206 case MachineOperand::MO_ConstantPoolIndex:
207 MCOp = GetSymbolRef(MO, AP.GetCPISymbol(MO.getIndex()), AP, isDarwin);
208 break;
209 case MachineOperand::MO_BlockAddress:
210 MCOp = GetSymbolRef(MO,AP.GetBlockAddressSymbol(MO.getBlockAddress()),AP,
211 isDarwin);
212 break;
213 case MachineOperand::MO_RegisterMask:
214 continue;
215 }
216
217 OutMI.addOperand(MCOp);
218 }
219 }
220