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 "PPCELFStreamer.h" 17 #include "PPCTargetStreamer.h" 18 #include "PPCXCOFFStreamer.h" 19 #include "TargetInfo/PowerPCTargetInfo.h" 20 #include "llvm/ADT/SmallPtrSet.h" 21 #include "llvm/ADT/StringRef.h" 22 #include "llvm/ADT/Triple.h" 23 #include "llvm/BinaryFormat/ELF.h" 24 #include "llvm/MC/MCAsmBackend.h" 25 #include "llvm/MC/MCAssembler.h" 26 #include "llvm/MC/MCCodeEmitter.h" 27 #include "llvm/MC/MCContext.h" 28 #include "llvm/MC/MCDwarf.h" 29 #include "llvm/MC/MCELFStreamer.h" 30 #include "llvm/MC/MCExpr.h" 31 #include "llvm/MC/MCInstrInfo.h" 32 #include "llvm/MC/MCObjectWriter.h" 33 #include "llvm/MC/MCRegisterInfo.h" 34 #include "llvm/MC/MCSectionXCOFF.h" 35 #include "llvm/MC/MCStreamer.h" 36 #include "llvm/MC/MCSubtargetInfo.h" 37 #include "llvm/MC/MCSymbol.h" 38 #include "llvm/MC/MCSymbolELF.h" 39 #include "llvm/MC/MCSymbolXCOFF.h" 40 #include "llvm/Support/Casting.h" 41 #include "llvm/Support/CodeGen.h" 42 #include "llvm/Support/ErrorHandling.h" 43 #include "llvm/Support/FormattedStream.h" 44 #include "llvm/Support/TargetRegistry.h" 45 #include "llvm/Support/raw_ostream.h" 46 47 using namespace llvm; 48 49 #define GET_INSTRINFO_MC_DESC 50 #include "PPCGenInstrInfo.inc" 51 52 #define GET_SUBTARGETINFO_MC_DESC 53 #include "PPCGenSubtargetInfo.inc" 54 55 #define GET_REGINFO_MC_DESC 56 #include "PPCGenRegisterInfo.inc" 57 58 PPCTargetStreamer::PPCTargetStreamer(MCStreamer &S) : MCTargetStreamer(S) {} 59 60 // Pin the vtable to this file. 61 PPCTargetStreamer::~PPCTargetStreamer() = default; 62 63 static MCInstrInfo *createPPCMCInstrInfo() { 64 MCInstrInfo *X = new MCInstrInfo(); 65 InitPPCMCInstrInfo(X); 66 return X; 67 } 68 69 static MCRegisterInfo *createPPCMCRegisterInfo(const Triple &TT) { 70 bool isPPC64 = 71 (TT.getArch() == Triple::ppc64 || TT.getArch() == Triple::ppc64le); 72 unsigned Flavour = isPPC64 ? 0 : 1; 73 unsigned RA = isPPC64 ? PPC::LR8 : PPC::LR; 74 75 MCRegisterInfo *X = new MCRegisterInfo(); 76 InitPPCMCRegisterInfo(X, RA, Flavour, Flavour); 77 return X; 78 } 79 80 static MCSubtargetInfo *createPPCMCSubtargetInfo(const Triple &TT, 81 StringRef CPU, StringRef FS) { 82 // Set some default feature to MC layer. 83 std::string FullFS = std::string(FS); 84 85 if (TT.isOSAIX()) { 86 if (!FullFS.empty()) 87 FullFS = "+aix," + FullFS; 88 else 89 FullFS = "+aix"; 90 } 91 92 return createPPCMCSubtargetInfoImpl(TT, CPU, /*TuneCPU*/ CPU, FullFS); 93 } 94 95 static MCAsmInfo *createPPCMCAsmInfo(const MCRegisterInfo &MRI, 96 const Triple &TheTriple, 97 const MCTargetOptions &Options) { 98 bool isPPC64 = (TheTriple.getArch() == Triple::ppc64 || 99 TheTriple.getArch() == Triple::ppc64le); 100 101 MCAsmInfo *MAI; 102 if (TheTriple.isOSBinFormatXCOFF()) 103 MAI = new PPCXCOFFMCAsmInfo(isPPC64, TheTriple); 104 else 105 MAI = new PPCELFMCAsmInfo(isPPC64, TheTriple); 106 107 // Initial state of the frame pointer is R1. 108 unsigned Reg = isPPC64 ? PPC::X1 : PPC::R1; 109 MCCFIInstruction Inst = 110 MCCFIInstruction::cfiDefCfa(nullptr, MRI.getDwarfRegNum(Reg, true), 0); 111 MAI->addInitialFrameState(Inst); 112 113 return MAI; 114 } 115 116 static MCStreamer * 117 createPPCELFStreamer(const Triple &T, MCContext &Context, 118 std::unique_ptr<MCAsmBackend> &&MAB, 119 std::unique_ptr<MCObjectWriter> &&OW, 120 std::unique_ptr<MCCodeEmitter> &&Emitter, bool RelaxAll) { 121 return createPPCELFStreamer(Context, std::move(MAB), std::move(OW), 122 std::move(Emitter)); 123 } 124 125 static MCStreamer *createPPCXCOFFStreamer( 126 const Triple &T, MCContext &Context, std::unique_ptr<MCAsmBackend> &&MAB, 127 std::unique_ptr<MCObjectWriter> &&OW, 128 std::unique_ptr<MCCodeEmitter> &&Emitter, bool RelaxAll) { 129 return createPPCXCOFFStreamer(Context, std::move(MAB), std::move(OW), 130 std::move(Emitter)); 131 } 132 133 namespace { 134 135 class PPCTargetAsmStreamer : public PPCTargetStreamer { 136 formatted_raw_ostream &OS; 137 138 public: 139 PPCTargetAsmStreamer(MCStreamer &S, formatted_raw_ostream &OS) 140 : PPCTargetStreamer(S), OS(OS) {} 141 142 void emitTCEntry(const MCSymbol &S, 143 MCSymbolRefExpr::VariantKind Kind) override { 144 if (const MCSymbolXCOFF *XSym = dyn_cast<MCSymbolXCOFF>(&S)) { 145 MCSymbolXCOFF *TCSym = 146 cast<MCSectionXCOFF>(Streamer.getCurrentSectionOnly()) 147 ->getQualNameSymbol(); 148 // If the variant kind is TLSGD the entry represents the region handle for 149 // the symbol, we prefix the name with a dot and we add the @m 150 // relocation specifier. 151 if (Kind == MCSymbolRefExpr::VariantKind::VK_PPC_TLSGD) 152 OS << "\t.tc ." << TCSym->getName() << "," << XSym->getName() << "@m\n"; 153 else 154 OS << "\t.tc " << TCSym->getName() << "," << XSym->getName() << '\n'; 155 156 if (TCSym->hasRename()) 157 Streamer.emitXCOFFRenameDirective(TCSym, TCSym->getSymbolTableName()); 158 return; 159 } 160 161 OS << "\t.tc " << S.getName() << "[TC]," << S.getName() << '\n'; 162 } 163 164 void emitMachine(StringRef CPU) override { 165 OS << "\t.machine " << CPU << '\n'; 166 } 167 168 void emitAbiVersion(int AbiVersion) override { 169 OS << "\t.abiversion " << AbiVersion << '\n'; 170 } 171 172 void emitLocalEntry(MCSymbolELF *S, const MCExpr *LocalOffset) override { 173 const MCAsmInfo *MAI = Streamer.getContext().getAsmInfo(); 174 175 OS << "\t.localentry\t"; 176 S->print(OS, MAI); 177 OS << ", "; 178 LocalOffset->print(OS, MAI); 179 OS << '\n'; 180 } 181 }; 182 183 class PPCTargetELFStreamer : public PPCTargetStreamer { 184 public: 185 PPCTargetELFStreamer(MCStreamer &S) : PPCTargetStreamer(S) {} 186 187 MCELFStreamer &getStreamer() { 188 return static_cast<MCELFStreamer &>(Streamer); 189 } 190 191 void emitTCEntry(const MCSymbol &S, 192 MCSymbolRefExpr::VariantKind Kind) override { 193 // Creates a R_PPC64_TOC relocation 194 Streamer.emitValueToAlignment(8); 195 Streamer.emitSymbolValue(&S, 8); 196 } 197 198 void emitMachine(StringRef CPU) override { 199 // FIXME: Is there anything to do in here or does this directive only 200 // limit the parser? 201 } 202 203 void emitAbiVersion(int AbiVersion) override { 204 MCAssembler &MCA = getStreamer().getAssembler(); 205 unsigned Flags = MCA.getELFHeaderEFlags(); 206 Flags &= ~ELF::EF_PPC64_ABI; 207 Flags |= (AbiVersion & ELF::EF_PPC64_ABI); 208 MCA.setELFHeaderEFlags(Flags); 209 } 210 211 void emitLocalEntry(MCSymbolELF *S, const MCExpr *LocalOffset) override { 212 MCAssembler &MCA = getStreamer().getAssembler(); 213 214 // encodePPC64LocalEntryOffset will report an error if it cannot 215 // encode LocalOffset. 216 unsigned Encoded = encodePPC64LocalEntryOffset(LocalOffset); 217 218 unsigned Other = S->getOther(); 219 Other &= ~ELF::STO_PPC64_LOCAL_MASK; 220 Other |= Encoded; 221 S->setOther(Other); 222 223 // For GAS compatibility, unless we already saw a .abiversion directive, 224 // set e_flags to indicate ELFv2 ABI. 225 unsigned Flags = MCA.getELFHeaderEFlags(); 226 if ((Flags & ELF::EF_PPC64_ABI) == 0) 227 MCA.setELFHeaderEFlags(Flags | 2); 228 } 229 230 void emitAssignment(MCSymbol *S, const MCExpr *Value) override { 231 auto *Symbol = cast<MCSymbolELF>(S); 232 233 // When encoding an assignment to set symbol A to symbol B, also copy 234 // the st_other bits encoding the local entry point offset. 235 if (copyLocalEntry(Symbol, Value)) 236 UpdateOther.insert(Symbol); 237 else 238 UpdateOther.erase(Symbol); 239 } 240 241 void finish() override { 242 for (auto *Sym : UpdateOther) 243 if (Sym->isVariable()) 244 copyLocalEntry(Sym, Sym->getVariableValue()); 245 246 // Clear the set of symbols that needs to be updated so the streamer can 247 // be reused without issues. 248 UpdateOther.clear(); 249 } 250 251 private: 252 SmallPtrSet<MCSymbolELF *, 32> UpdateOther; 253 254 bool copyLocalEntry(MCSymbolELF *D, const MCExpr *S) { 255 auto *Ref = dyn_cast<const MCSymbolRefExpr>(S); 256 if (!Ref) 257 return false; 258 const auto &RhsSym = cast<MCSymbolELF>(Ref->getSymbol()); 259 unsigned Other = D->getOther(); 260 Other &= ~ELF::STO_PPC64_LOCAL_MASK; 261 Other |= RhsSym.getOther() & ELF::STO_PPC64_LOCAL_MASK; 262 D->setOther(Other); 263 return true; 264 } 265 266 unsigned encodePPC64LocalEntryOffset(const MCExpr *LocalOffset) { 267 MCAssembler &MCA = getStreamer().getAssembler(); 268 int64_t Offset; 269 if (!LocalOffset->evaluateAsAbsolute(Offset, MCA)) 270 MCA.getContext().reportFatalError( 271 LocalOffset->getLoc(), ".localentry expression must be absolute."); 272 273 switch (Offset) { 274 default: 275 MCA.getContext().reportFatalError( 276 LocalOffset->getLoc(), 277 ".localentry expression is not a valid power of 2."); 278 case 0: 279 return 0; 280 case 1: 281 return 1 << ELF::STO_PPC64_LOCAL_BIT; 282 case 4: 283 case 8: 284 case 16: 285 case 32: 286 case 64: 287 return (int)Log2(Offset) << (int)ELF::STO_PPC64_LOCAL_BIT; 288 } 289 } 290 }; 291 292 class PPCTargetMachOStreamer : public PPCTargetStreamer { 293 public: 294 PPCTargetMachOStreamer(MCStreamer &S) : PPCTargetStreamer(S) {} 295 296 void emitTCEntry(const MCSymbol &S, 297 MCSymbolRefExpr::VariantKind Kind) override { 298 llvm_unreachable("Unknown pseudo-op: .tc"); 299 } 300 301 void emitMachine(StringRef CPU) override { 302 // FIXME: We should update the CPUType, CPUSubType in the Object file if 303 // the new values are different from the defaults. 304 } 305 306 void emitAbiVersion(int AbiVersion) override { 307 llvm_unreachable("Unknown pseudo-op: .abiversion"); 308 } 309 310 void emitLocalEntry(MCSymbolELF *S, const MCExpr *LocalOffset) override { 311 llvm_unreachable("Unknown pseudo-op: .localentry"); 312 } 313 }; 314 315 class PPCTargetXCOFFStreamer : public PPCTargetStreamer { 316 public: 317 PPCTargetXCOFFStreamer(MCStreamer &S) : PPCTargetStreamer(S) {} 318 319 void emitTCEntry(const MCSymbol &S, 320 MCSymbolRefExpr::VariantKind Kind) override { 321 const MCAsmInfo *MAI = Streamer.getContext().getAsmInfo(); 322 const unsigned PointerSize = MAI->getCodePointerSize(); 323 Streamer.emitValueToAlignment(PointerSize); 324 Streamer.emitSymbolValue(&S, PointerSize); 325 } 326 327 void emitMachine(StringRef CPU) override { 328 llvm_unreachable("Machine pseudo-ops are invalid for XCOFF."); 329 } 330 331 void emitAbiVersion(int AbiVersion) override { 332 llvm_unreachable("ABI-version pseudo-ops are invalid for XCOFF."); 333 } 334 335 void emitLocalEntry(MCSymbolELF *S, const MCExpr *LocalOffset) override { 336 llvm_unreachable("Local-entry pseudo-ops are invalid for XCOFF."); 337 } 338 }; 339 340 } // end anonymous namespace 341 342 static MCTargetStreamer *createAsmTargetStreamer(MCStreamer &S, 343 formatted_raw_ostream &OS, 344 MCInstPrinter *InstPrint, 345 bool isVerboseAsm) { 346 return new PPCTargetAsmStreamer(S, OS); 347 } 348 349 static MCTargetStreamer * 350 createObjectTargetStreamer(MCStreamer &S, const MCSubtargetInfo &STI) { 351 const Triple &TT = STI.getTargetTriple(); 352 if (TT.isOSBinFormatELF()) 353 return new PPCTargetELFStreamer(S); 354 if (TT.isOSBinFormatXCOFF()) 355 return new PPCTargetXCOFFStreamer(S); 356 return new PPCTargetMachOStreamer(S); 357 } 358 359 static MCInstPrinter *createPPCMCInstPrinter(const Triple &T, 360 unsigned SyntaxVariant, 361 const MCAsmInfo &MAI, 362 const MCInstrInfo &MII, 363 const MCRegisterInfo &MRI) { 364 return new PPCInstPrinter(MAI, MII, MRI, T); 365 } 366 367 extern "C" LLVM_EXTERNAL_VISIBILITY void LLVMInitializePowerPCTargetMC() { 368 for (Target *T : {&getThePPC32Target(), &getThePPC32LETarget(), 369 &getThePPC64Target(), &getThePPC64LETarget()}) { 370 // Register the MC asm info. 371 RegisterMCAsmInfoFn C(*T, createPPCMCAsmInfo); 372 373 // Register the MC instruction info. 374 TargetRegistry::RegisterMCInstrInfo(*T, createPPCMCInstrInfo); 375 376 // Register the MC register info. 377 TargetRegistry::RegisterMCRegInfo(*T, createPPCMCRegisterInfo); 378 379 // Register the MC subtarget info. 380 TargetRegistry::RegisterMCSubtargetInfo(*T, createPPCMCSubtargetInfo); 381 382 // Register the MC Code Emitter 383 TargetRegistry::RegisterMCCodeEmitter(*T, createPPCMCCodeEmitter); 384 385 // Register the asm backend. 386 TargetRegistry::RegisterMCAsmBackend(*T, createPPCAsmBackend); 387 388 // Register the elf streamer. 389 TargetRegistry::RegisterELFStreamer(*T, createPPCELFStreamer); 390 391 // Register the XCOFF streamer. 392 TargetRegistry::RegisterXCOFFStreamer(*T, createPPCXCOFFStreamer); 393 394 // Register the object target streamer. 395 TargetRegistry::RegisterObjectTargetStreamer(*T, 396 createObjectTargetStreamer); 397 398 // Register the asm target streamer. 399 TargetRegistry::RegisterAsmTargetStreamer(*T, createAsmTargetStreamer); 400 401 // Register the MCInstPrinter. 402 TargetRegistry::RegisterMCInstPrinter(*T, createPPCMCInstPrinter); 403 } 404 } 405