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/MC/MCSymbolXCOFF.h" 34 #include "llvm/Support/Casting.h" 35 #include "llvm/Support/CodeGen.h" 36 #include "llvm/Support/ErrorHandling.h" 37 #include "llvm/Support/FormattedStream.h" 38 #include "llvm/Support/TargetRegistry.h" 39 #include "llvm/Support/raw_ostream.h" 40 41 using namespace llvm; 42 43 #define GET_INSTRINFO_MC_DESC 44 #include "PPCGenInstrInfo.inc" 45 46 #define GET_SUBTARGETINFO_MC_DESC 47 #include "PPCGenSubtargetInfo.inc" 48 49 #define GET_REGINFO_MC_DESC 50 #include "PPCGenRegisterInfo.inc" 51 52 PPCTargetStreamer::PPCTargetStreamer(MCStreamer &S) : MCTargetStreamer(S) {} 53 54 // Pin the vtable to this file. 55 PPCTargetStreamer::~PPCTargetStreamer() = default; 56 57 static MCInstrInfo *createPPCMCInstrInfo() { 58 MCInstrInfo *X = new MCInstrInfo(); 59 InitPPCMCInstrInfo(X); 60 return X; 61 } 62 63 static MCRegisterInfo *createPPCMCRegisterInfo(const Triple &TT) { 64 bool isPPC64 = 65 (TT.getArch() == Triple::ppc64 || TT.getArch() == Triple::ppc64le); 66 unsigned Flavour = isPPC64 ? 0 : 1; 67 unsigned RA = isPPC64 ? PPC::LR8 : PPC::LR; 68 69 MCRegisterInfo *X = new MCRegisterInfo(); 70 InitPPCMCRegisterInfo(X, RA, Flavour, Flavour); 71 return X; 72 } 73 74 static MCSubtargetInfo *createPPCMCSubtargetInfo(const Triple &TT, 75 StringRef CPU, StringRef FS) { 76 return createPPCMCSubtargetInfoImpl(TT, CPU, FS); 77 } 78 79 static MCAsmInfo *createPPCMCAsmInfo(const MCRegisterInfo &MRI, 80 const Triple &TheTriple, 81 const MCTargetOptions &Options) { 82 bool isPPC64 = (TheTriple.getArch() == Triple::ppc64 || 83 TheTriple.getArch() == Triple::ppc64le); 84 85 MCAsmInfo *MAI; 86 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 const MCAsmInfo *MAI = Streamer.getContext().getAsmInfo(); 111 OS << "\t.tc "; 112 OS << (MAI->getSymbolsHaveSMC() 113 ? cast<MCSymbolXCOFF>(S).getUnqualifiedName() 114 : S.getName()); 115 OS << "[TC],"; 116 OS << S.getName(); 117 OS << '\n'; 118 } 119 120 void emitMachine(StringRef CPU) override { 121 OS << "\t.machine " << CPU << '\n'; 122 } 123 124 void emitAbiVersion(int AbiVersion) override { 125 OS << "\t.abiversion " << AbiVersion << '\n'; 126 } 127 128 void emitLocalEntry(MCSymbolELF *S, const MCExpr *LocalOffset) override { 129 const MCAsmInfo *MAI = Streamer.getContext().getAsmInfo(); 130 131 OS << "\t.localentry\t"; 132 S->print(OS, MAI); 133 OS << ", "; 134 LocalOffset->print(OS, MAI); 135 OS << '\n'; 136 } 137 }; 138 139 class PPCTargetELFStreamer : public PPCTargetStreamer { 140 public: 141 PPCTargetELFStreamer(MCStreamer &S) : PPCTargetStreamer(S) {} 142 143 MCELFStreamer &getStreamer() { 144 return static_cast<MCELFStreamer &>(Streamer); 145 } 146 147 void emitTCEntry(const MCSymbol &S) override { 148 // Creates a R_PPC64_TOC relocation 149 Streamer.EmitValueToAlignment(8); 150 Streamer.EmitSymbolValue(&S, 8); 151 } 152 153 void emitMachine(StringRef CPU) override { 154 // FIXME: Is there anything to do in here or does this directive only 155 // limit the parser? 156 } 157 158 void emitAbiVersion(int AbiVersion) override { 159 MCAssembler &MCA = getStreamer().getAssembler(); 160 unsigned Flags = MCA.getELFHeaderEFlags(); 161 Flags &= ~ELF::EF_PPC64_ABI; 162 Flags |= (AbiVersion & ELF::EF_PPC64_ABI); 163 MCA.setELFHeaderEFlags(Flags); 164 } 165 166 void emitLocalEntry(MCSymbolELF *S, const MCExpr *LocalOffset) override { 167 MCAssembler &MCA = getStreamer().getAssembler(); 168 169 int64_t Res; 170 if (!LocalOffset->evaluateAsAbsolute(Res, MCA)) 171 report_fatal_error(".localentry expression must be absolute."); 172 173 unsigned Encoded = ELF::encodePPC64LocalEntryOffset(Res); 174 if (Res != ELF::decodePPC64LocalEntryOffset(Encoded)) 175 report_fatal_error(".localentry expression cannot be encoded."); 176 177 unsigned Other = S->getOther(); 178 Other &= ~ELF::STO_PPC64_LOCAL_MASK; 179 Other |= Encoded; 180 S->setOther(Other); 181 182 // For GAS compatibility, unless we already saw a .abiversion directive, 183 // set e_flags to indicate ELFv2 ABI. 184 unsigned Flags = MCA.getELFHeaderEFlags(); 185 if ((Flags & ELF::EF_PPC64_ABI) == 0) 186 MCA.setELFHeaderEFlags(Flags | 2); 187 } 188 189 void emitAssignment(MCSymbol *S, const MCExpr *Value) override { 190 auto *Symbol = cast<MCSymbolELF>(S); 191 192 // When encoding an assignment to set symbol A to symbol B, also copy 193 // the st_other bits encoding the local entry point offset. 194 if (copyLocalEntry(Symbol, Value)) 195 UpdateOther.insert(Symbol); 196 else 197 UpdateOther.erase(Symbol); 198 } 199 200 void finish() override { 201 for (auto *Sym : UpdateOther) 202 if (Sym->isVariable()) 203 copyLocalEntry(Sym, Sym->getVariableValue()); 204 } 205 206 private: 207 SmallPtrSet<MCSymbolELF *, 32> UpdateOther; 208 209 bool copyLocalEntry(MCSymbolELF *D, const MCExpr *S) { 210 auto *Ref = dyn_cast<const MCSymbolRefExpr>(S); 211 if (!Ref) 212 return false; 213 const auto &RhsSym = cast<MCSymbolELF>(Ref->getSymbol()); 214 unsigned Other = D->getOther(); 215 Other &= ~ELF::STO_PPC64_LOCAL_MASK; 216 Other |= RhsSym.getOther() & ELF::STO_PPC64_LOCAL_MASK; 217 D->setOther(Other); 218 return true; 219 } 220 }; 221 222 class PPCTargetMachOStreamer : public PPCTargetStreamer { 223 public: 224 PPCTargetMachOStreamer(MCStreamer &S) : PPCTargetStreamer(S) {} 225 226 void emitTCEntry(const MCSymbol &S) override { 227 llvm_unreachable("Unknown pseudo-op: .tc"); 228 } 229 230 void emitMachine(StringRef CPU) override { 231 // FIXME: We should update the CPUType, CPUSubType in the Object file if 232 // the new values are different from the defaults. 233 } 234 235 void emitAbiVersion(int AbiVersion) override { 236 llvm_unreachable("Unknown pseudo-op: .abiversion"); 237 } 238 239 void emitLocalEntry(MCSymbolELF *S, const MCExpr *LocalOffset) override { 240 llvm_unreachable("Unknown pseudo-op: .localentry"); 241 } 242 }; 243 244 class PPCTargetXCOFFStreamer : public PPCTargetStreamer { 245 public: 246 PPCTargetXCOFFStreamer(MCStreamer &S) : PPCTargetStreamer(S) {} 247 248 void emitTCEntry(const MCSymbol &S) override { 249 const MCAsmInfo *MAI = Streamer.getContext().getAsmInfo(); 250 const unsigned PointerSize = MAI->getCodePointerSize(); 251 Streamer.EmitValueToAlignment(PointerSize); 252 Streamer.EmitSymbolValue(&S, PointerSize); 253 } 254 255 void emitMachine(StringRef CPU) override { 256 llvm_unreachable("Machine pseudo-ops are invalid for XCOFF."); 257 } 258 259 void emitAbiVersion(int AbiVersion) override { 260 llvm_unreachable("ABI-version pseudo-ops are invalid for XCOFF."); 261 } 262 263 void emitLocalEntry(MCSymbolELF *S, const MCExpr *LocalOffset) override { 264 llvm_unreachable("Local-entry pseudo-ops are invalid for XCOFF."); 265 } 266 }; 267 268 } // end anonymous namespace 269 270 static MCTargetStreamer *createAsmTargetStreamer(MCStreamer &S, 271 formatted_raw_ostream &OS, 272 MCInstPrinter *InstPrint, 273 bool isVerboseAsm) { 274 return new PPCTargetAsmStreamer(S, OS); 275 } 276 277 static MCTargetStreamer * 278 createObjectTargetStreamer(MCStreamer &S, const MCSubtargetInfo &STI) { 279 const Triple &TT = STI.getTargetTriple(); 280 if (TT.isOSBinFormatELF()) 281 return new PPCTargetELFStreamer(S); 282 if (TT.isOSBinFormatXCOFF()) 283 return new PPCTargetXCOFFStreamer(S); 284 return new PPCTargetMachOStreamer(S); 285 } 286 287 static MCInstPrinter *createPPCMCInstPrinter(const Triple &T, 288 unsigned SyntaxVariant, 289 const MCAsmInfo &MAI, 290 const MCInstrInfo &MII, 291 const MCRegisterInfo &MRI) { 292 return new PPCInstPrinter(MAI, MII, MRI, T); 293 } 294 295 extern "C" LLVM_EXTERNAL_VISIBILITY void LLVMInitializePowerPCTargetMC() { 296 for (Target *T : 297 {&getThePPC32Target(), &getThePPC64Target(), &getThePPC64LETarget()}) { 298 // Register the MC asm info. 299 RegisterMCAsmInfoFn C(*T, createPPCMCAsmInfo); 300 301 // Register the MC instruction info. 302 TargetRegistry::RegisterMCInstrInfo(*T, createPPCMCInstrInfo); 303 304 // Register the MC register info. 305 TargetRegistry::RegisterMCRegInfo(*T, createPPCMCRegisterInfo); 306 307 // Register the MC subtarget info. 308 TargetRegistry::RegisterMCSubtargetInfo(*T, createPPCMCSubtargetInfo); 309 310 // Register the MC Code Emitter 311 TargetRegistry::RegisterMCCodeEmitter(*T, createPPCMCCodeEmitter); 312 313 // Register the asm backend. 314 TargetRegistry::RegisterMCAsmBackend(*T, createPPCAsmBackend); 315 316 // Register the object target streamer. 317 TargetRegistry::RegisterObjectTargetStreamer(*T, 318 createObjectTargetStreamer); 319 320 // Register the asm target streamer. 321 TargetRegistry::RegisterAsmTargetStreamer(*T, createAsmTargetStreamer); 322 323 // Register the MCInstPrinter. 324 TargetRegistry::RegisterMCInstPrinter(*T, createPPCMCInstPrinter); 325 } 326 } 327