1 //===-- PPCMCTargetDesc.cpp - PowerPC Target Descriptions -----------------===// 2 // 3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. 4 // See https://llvm.org/LICENSE.txt for license information. 5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception 6 // 7 //===----------------------------------------------------------------------===// 8 // 9 // This file provides PowerPC specific target descriptions. 10 // 11 //===----------------------------------------------------------------------===// 12 13 #include "MCTargetDesc/PPCMCTargetDesc.h" 14 #include "MCTargetDesc/PPCInstPrinter.h" 15 #include "MCTargetDesc/PPCMCAsmInfo.h" 16 #include "PPCTargetStreamer.h" 17 #include "TargetInfo/PowerPCTargetInfo.h" 18 #include "llvm/ADT/SmallPtrSet.h" 19 #include "llvm/ADT/StringRef.h" 20 #include "llvm/ADT/Triple.h" 21 #include "llvm/BinaryFormat/ELF.h" 22 #include "llvm/MC/MCAssembler.h" 23 #include "llvm/MC/MCContext.h" 24 #include "llvm/MC/MCDwarf.h" 25 #include "llvm/MC/MCELFStreamer.h" 26 #include "llvm/MC/MCExpr.h" 27 #include "llvm/MC/MCInstrInfo.h" 28 #include "llvm/MC/MCRegisterInfo.h" 29 #include "llvm/MC/MCStreamer.h" 30 #include "llvm/MC/MCSubtargetInfo.h" 31 #include "llvm/MC/MCSymbol.h" 32 #include "llvm/MC/MCSymbolELF.h" 33 #include "llvm/Support/Casting.h" 34 #include "llvm/Support/CodeGen.h" 35 #include "llvm/Support/ErrorHandling.h" 36 #include "llvm/Support/FormattedStream.h" 37 #include "llvm/Support/TargetRegistry.h" 38 #include "llvm/Support/raw_ostream.h" 39 40 using namespace llvm; 41 42 #define GET_INSTRINFO_MC_DESC 43 #include "PPCGenInstrInfo.inc" 44 45 #define GET_SUBTARGETINFO_MC_DESC 46 #include "PPCGenSubtargetInfo.inc" 47 48 #define GET_REGINFO_MC_DESC 49 #include "PPCGenRegisterInfo.inc" 50 51 PPCTargetStreamer::PPCTargetStreamer(MCStreamer &S) : MCTargetStreamer(S) {} 52 53 // Pin the vtable to this file. 54 PPCTargetStreamer::~PPCTargetStreamer() = default; 55 56 static MCInstrInfo *createPPCMCInstrInfo() { 57 MCInstrInfo *X = new MCInstrInfo(); 58 InitPPCMCInstrInfo(X); 59 return X; 60 } 61 62 static MCRegisterInfo *createPPCMCRegisterInfo(const Triple &TT) { 63 bool isPPC64 = 64 (TT.getArch() == Triple::ppc64 || TT.getArch() == Triple::ppc64le); 65 unsigned Flavour = isPPC64 ? 0 : 1; 66 unsigned RA = isPPC64 ? PPC::LR8 : PPC::LR; 67 68 MCRegisterInfo *X = new MCRegisterInfo(); 69 InitPPCMCRegisterInfo(X, RA, Flavour, Flavour); 70 return X; 71 } 72 73 static MCSubtargetInfo *createPPCMCSubtargetInfo(const Triple &TT, 74 StringRef CPU, StringRef FS) { 75 return createPPCMCSubtargetInfoImpl(TT, CPU, FS); 76 } 77 78 static MCAsmInfo *createPPCMCAsmInfo(const MCRegisterInfo &MRI, 79 const Triple &TheTriple) { 80 bool isPPC64 = (TheTriple.getArch() == Triple::ppc64 || 81 TheTriple.getArch() == Triple::ppc64le); 82 83 MCAsmInfo *MAI; 84 if (TheTriple.isOSDarwin()) 85 MAI = new PPCMCAsmInfoDarwin(isPPC64, TheTriple); 86 else if (TheTriple.isOSBinFormatXCOFF()) 87 MAI = new PPCXCOFFMCAsmInfo(isPPC64, TheTriple); 88 else 89 MAI = new PPCELFMCAsmInfo(isPPC64, TheTriple); 90 91 // Initial state of the frame pointer is R1. 92 unsigned Reg = isPPC64 ? PPC::X1 : PPC::R1; 93 MCCFIInstruction Inst = 94 MCCFIInstruction::createDefCfa(nullptr, MRI.getDwarfRegNum(Reg, true), 0); 95 MAI->addInitialFrameState(Inst); 96 97 return MAI; 98 } 99 100 namespace { 101 102 class PPCTargetAsmStreamer : public PPCTargetStreamer { 103 formatted_raw_ostream &OS; 104 105 public: 106 PPCTargetAsmStreamer(MCStreamer &S, formatted_raw_ostream &OS) 107 : PPCTargetStreamer(S), OS(OS) {} 108 109 void emitTCEntry(const MCSymbol &S) override { 110 OS << "\t.tc "; 111 OS << S.getName(); 112 OS << "[TC],"; 113 OS << S.getName(); 114 OS << '\n'; 115 } 116 117 void emitMachine(StringRef CPU) override { 118 OS << "\t.machine " << CPU << '\n'; 119 } 120 121 void emitAbiVersion(int AbiVersion) override { 122 OS << "\t.abiversion " << AbiVersion << '\n'; 123 } 124 125 void emitLocalEntry(MCSymbolELF *S, const MCExpr *LocalOffset) override { 126 const MCAsmInfo *MAI = Streamer.getContext().getAsmInfo(); 127 128 OS << "\t.localentry\t"; 129 S->print(OS, MAI); 130 OS << ", "; 131 LocalOffset->print(OS, MAI); 132 OS << '\n'; 133 } 134 }; 135 136 class PPCTargetELFStreamer : public PPCTargetStreamer { 137 public: 138 PPCTargetELFStreamer(MCStreamer &S) : PPCTargetStreamer(S) {} 139 140 MCELFStreamer &getStreamer() { 141 return static_cast<MCELFStreamer &>(Streamer); 142 } 143 144 void emitTCEntry(const MCSymbol &S) override { 145 // Creates a R_PPC64_TOC relocation 146 Streamer.EmitValueToAlignment(8); 147 Streamer.EmitSymbolValue(&S, 8); 148 } 149 150 void emitMachine(StringRef CPU) override { 151 // FIXME: Is there anything to do in here or does this directive only 152 // limit the parser? 153 } 154 155 void emitAbiVersion(int AbiVersion) override { 156 MCAssembler &MCA = getStreamer().getAssembler(); 157 unsigned Flags = MCA.getELFHeaderEFlags(); 158 Flags &= ~ELF::EF_PPC64_ABI; 159 Flags |= (AbiVersion & ELF::EF_PPC64_ABI); 160 MCA.setELFHeaderEFlags(Flags); 161 } 162 163 void emitLocalEntry(MCSymbolELF *S, const MCExpr *LocalOffset) override { 164 MCAssembler &MCA = getStreamer().getAssembler(); 165 166 int64_t Res; 167 if (!LocalOffset->evaluateAsAbsolute(Res, MCA)) 168 report_fatal_error(".localentry expression must be absolute."); 169 170 unsigned Encoded = ELF::encodePPC64LocalEntryOffset(Res); 171 if (Res != ELF::decodePPC64LocalEntryOffset(Encoded)) 172 report_fatal_error(".localentry expression cannot be encoded."); 173 174 unsigned Other = S->getOther(); 175 Other &= ~ELF::STO_PPC64_LOCAL_MASK; 176 Other |= Encoded; 177 S->setOther(Other); 178 179 // For GAS compatibility, unless we already saw a .abiversion directive, 180 // set e_flags to indicate ELFv2 ABI. 181 unsigned Flags = MCA.getELFHeaderEFlags(); 182 if ((Flags & ELF::EF_PPC64_ABI) == 0) 183 MCA.setELFHeaderEFlags(Flags | 2); 184 } 185 186 void emitAssignment(MCSymbol *S, const MCExpr *Value) override { 187 auto *Symbol = cast<MCSymbolELF>(S); 188 189 // When encoding an assignment to set symbol A to symbol B, also copy 190 // the st_other bits encoding the local entry point offset. 191 if (copyLocalEntry(Symbol, Value)) 192 UpdateOther.insert(Symbol); 193 else 194 UpdateOther.erase(Symbol); 195 } 196 197 void finish() override { 198 for (auto *Sym : UpdateOther) 199 copyLocalEntry(Sym, Sym->getVariableValue()); 200 } 201 202 private: 203 SmallPtrSet<MCSymbolELF *, 32> UpdateOther; 204 205 bool copyLocalEntry(MCSymbolELF *D, const MCExpr *S) { 206 auto *Ref = dyn_cast<const MCSymbolRefExpr>(S); 207 if (!Ref) 208 return false; 209 const auto &RhsSym = cast<MCSymbolELF>(Ref->getSymbol()); 210 unsigned Other = D->getOther(); 211 Other &= ~ELF::STO_PPC64_LOCAL_MASK; 212 Other |= RhsSym.getOther() & ELF::STO_PPC64_LOCAL_MASK; 213 D->setOther(Other); 214 return true; 215 } 216 }; 217 218 class PPCTargetMachOStreamer : public PPCTargetStreamer { 219 public: 220 PPCTargetMachOStreamer(MCStreamer &S) : PPCTargetStreamer(S) {} 221 222 void emitTCEntry(const MCSymbol &S) override { 223 llvm_unreachable("Unknown pseudo-op: .tc"); 224 } 225 226 void emitMachine(StringRef CPU) override { 227 // FIXME: We should update the CPUType, CPUSubType in the Object file if 228 // the new values are different from the defaults. 229 } 230 231 void emitAbiVersion(int AbiVersion) override { 232 llvm_unreachable("Unknown pseudo-op: .abiversion"); 233 } 234 235 void emitLocalEntry(MCSymbolELF *S, const MCExpr *LocalOffset) override { 236 llvm_unreachable("Unknown pseudo-op: .localentry"); 237 } 238 }; 239 240 class PPCTargetXCOFFStreamer : public PPCTargetStreamer { 241 public: 242 PPCTargetXCOFFStreamer(MCStreamer &S) : PPCTargetStreamer(S) {} 243 244 void emitTCEntry(const MCSymbol &S) override { 245 report_fatal_error("TOC entries not supported yet."); 246 } 247 248 void emitMachine(StringRef CPU) override { 249 llvm_unreachable("Machine pseudo-ops are invalid for XCOFF."); 250 } 251 252 void emitAbiVersion(int AbiVersion) override { 253 llvm_unreachable("ABI-version pseudo-ops are invalid for XCOFF."); 254 } 255 256 void emitLocalEntry(MCSymbolELF *S, const MCExpr *LocalOffset) override { 257 llvm_unreachable("Local-entry pseudo-ops are invalid for XCOFF."); 258 } 259 }; 260 261 } // end anonymous namespace 262 263 static MCTargetStreamer *createAsmTargetStreamer(MCStreamer &S, 264 formatted_raw_ostream &OS, 265 MCInstPrinter *InstPrint, 266 bool isVerboseAsm) { 267 return new PPCTargetAsmStreamer(S, OS); 268 } 269 270 static MCTargetStreamer * 271 createObjectTargetStreamer(MCStreamer &S, const MCSubtargetInfo &STI) { 272 const Triple &TT = STI.getTargetTriple(); 273 if (TT.isOSBinFormatELF()) 274 return new PPCTargetELFStreamer(S); 275 if (TT.isOSBinFormatXCOFF()) 276 return new PPCTargetXCOFFStreamer(S); 277 return new PPCTargetMachOStreamer(S); 278 } 279 280 static MCInstPrinter *createPPCMCInstPrinter(const Triple &T, 281 unsigned SyntaxVariant, 282 const MCAsmInfo &MAI, 283 const MCInstrInfo &MII, 284 const MCRegisterInfo &MRI) { 285 return new PPCInstPrinter(MAI, MII, MRI, T); 286 } 287 288 extern "C" void LLVMInitializePowerPCTargetMC() { 289 for (Target *T : 290 {&getThePPC32Target(), &getThePPC64Target(), &getThePPC64LETarget()}) { 291 // Register the MC asm info. 292 RegisterMCAsmInfoFn C(*T, createPPCMCAsmInfo); 293 294 // Register the MC instruction info. 295 TargetRegistry::RegisterMCInstrInfo(*T, createPPCMCInstrInfo); 296 297 // Register the MC register info. 298 TargetRegistry::RegisterMCRegInfo(*T, createPPCMCRegisterInfo); 299 300 // Register the MC subtarget info. 301 TargetRegistry::RegisterMCSubtargetInfo(*T, createPPCMCSubtargetInfo); 302 303 // Register the MC Code Emitter 304 TargetRegistry::RegisterMCCodeEmitter(*T, createPPCMCCodeEmitter); 305 306 // Register the asm backend. 307 TargetRegistry::RegisterMCAsmBackend(*T, createPPCAsmBackend); 308 309 // Register the object target streamer. 310 TargetRegistry::RegisterObjectTargetStreamer(*T, 311 createObjectTargetStreamer); 312 313 // Register the asm target streamer. 314 TargetRegistry::RegisterAsmTargetStreamer(*T, createAsmTargetStreamer); 315 316 // Register the MCInstPrinter. 317 TargetRegistry::RegisterMCInstPrinter(*T, createPPCMCInstPrinter); 318 } 319 } 320