src/llvm/lib/Object/IRObjectFile.cpp

   1 //===- IRObjectFile.cpp - IR object file implementation ---------*- C++ -*-===//
   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 // Part of the IRObjectFile class implementation.
  11 //
  12 //===----------------------------------------------------------------------===//
  13
  14 #include "llvm/Object/IRObjectFile.h"
  15 #include "RecordStreamer.h"
  16 #include "llvm/Bitcode/ReaderWriter.h"
  17 #include "llvm/IR/GVMaterializer.h"
  18 #include "llvm/IR/LLVMContext.h"
  19 #include "llvm/IR/Mangler.h"
  20 #include "llvm/IR/Module.h"
  21 #include "llvm/MC/MCAsmInfo.h"
  22 #include "llvm/MC/MCContext.h"
  23 #include "llvm/MC/MCInstrInfo.h"
  24 #include "llvm/MC/MCObjectFileInfo.h"
  25 #include "llvm/MC/MCParser/MCAsmParser.h"
  26 #include "llvm/MC/MCRegisterInfo.h"
  27 #include "llvm/MC/MCTargetAsmParser.h"
  28 #include "llvm/Object/ObjectFile.h"
  29 #include "llvm/Support/MemoryBuffer.h"
  30 #include "llvm/Support/SourceMgr.h"
  31 #include "llvm/Support/TargetRegistry.h"
  32 #include "llvm/Support/raw_ostream.h"
  33 using namespace llvm;
  34 using namespace object;
  35
  36 IRObjectFile::IRObjectFile(MemoryBufferRef Object, std::unique_ptr<Module> Mod)
  37     : SymbolicFile(Binary::ID_IR, Object), M(std::move(Mod)) {
  38   // If we have a DataLayout, setup a mangler.
  39   const DataLayout *DL = M->getDataLayout();
  40   if (!DL)
  41     return;
  42
  43   Mang.reset(new Mangler(DL));
  44
  45   const std::string &InlineAsm = M->getModuleInlineAsm();
  46   if (InlineAsm.empty())
  47     return;
  48
  49   StringRef Triple = M->getTargetTriple();
  50   std::string Err;
  51   const Target *T = TargetRegistry::lookupTarget(Triple, Err);
  52   if (!T)
  53     return;
  54
  55   std::unique_ptr<MCRegisterInfo> MRI(T->createMCRegInfo(Triple));
  56   if (!MRI)
  57     return;
  58
  59   std::unique_ptr<MCAsmInfo> MAI(T->createMCAsmInfo(*MRI, Triple));
  60   if (!MAI)
  61     return;
  62
  63   std::unique_ptr<MCSubtargetInfo> STI(
  64       T->createMCSubtargetInfo(Triple, "", ""));
  65   if (!STI)
  66     return;
  67
  68   std::unique_ptr<MCInstrInfo> MCII(T->createMCInstrInfo());
  69   if (!MCII)
  70     return;
  71
  72   MCObjectFileInfo MOFI;
  73   MCContext MCCtx(MAI.get(), MRI.get(), &MOFI);
  74   MOFI.InitMCObjectFileInfo(Triple, Reloc::Default, CodeModel::Default, MCCtx);
  75   std::unique_ptr<RecordStreamer> Streamer(new RecordStreamer(MCCtx));
  76
  77   std::unique_ptr<MemoryBuffer> Buffer(MemoryBuffer::getMemBuffer(InlineAsm));
  78   SourceMgr SrcMgr;
  79   SrcMgr.AddNewSourceBuffer(std::move(Buffer), SMLoc());
  80   std::unique_ptr<MCAsmParser> Parser(
  81       createMCAsmParser(SrcMgr, MCCtx, *Streamer, *MAI));
  82
  83   MCTargetOptions MCOptions;
  84   std::unique_ptr<MCTargetAsmParser> TAP(
  85       T->createMCAsmParser(*STI, *Parser, *MCII, MCOptions));
  86   if (!TAP)
  87     return;
  88
  89   Parser->setTargetParser(*TAP);
  90   if (Parser->Run(false))
  91     return;
  92
  93   for (auto &KV : *Streamer) {
  94     StringRef Key = KV.first();
  95     RecordStreamer::State Value = KV.second;
  96     uint32_t Res = BasicSymbolRef::SF_None;
  97     switch (Value) {
  98     case RecordStreamer::NeverSeen:
  99       llvm_unreachable("foo");
 100     case RecordStreamer::DefinedGlobal:
 101       Res |= BasicSymbolRef::SF_Global;
 102       break;
 103     case RecordStreamer::Defined:
 104       break;
 105     case RecordStreamer::Global:
 106     case RecordStreamer::Used:
 107       Res |= BasicSymbolRef::SF_Undefined;
 108       Res |= BasicSymbolRef::SF_Global;
 109       break;
 110     }
 111     AsmSymbols.push_back(
 112         std::make_pair<std::string, uint32_t>(Key, std::move(Res)));
 113   }
 114 }
 115
 116 IRObjectFile::~IRObjectFile() {
 117  }
 118
 119 static GlobalValue *getGV(DataRefImpl &Symb) {
 120   if ((Symb.p & 3) == 3)
 121     return nullptr;
 122
 123   return reinterpret_cast<GlobalValue*>(Symb.p & ~uintptr_t(3));
 124 }
 125
 126 static uintptr_t skipEmpty(Module::const_alias_iterator I, const Module &M) {
 127   if (I == M.alias_end())
 128     return 3;
 129   const GlobalValue *GV = &*I;
 130   return reinterpret_cast<uintptr_t>(GV) | 2;
 131 }
 132
 133 static uintptr_t skipEmpty(Module::const_global_iterator I, const Module &M) {
 134   if (I == M.global_end())
 135     return skipEmpty(M.alias_begin(), M);
 136   const GlobalValue *GV = &*I;
 137   return reinterpret_cast<uintptr_t>(GV) | 1;
 138 }
 139
 140 static uintptr_t skipEmpty(Module::const_iterator I, const Module &M) {
 141   if (I == M.end())
 142     return skipEmpty(M.global_begin(), M);
 143   const GlobalValue *GV = &*I;
 144   return reinterpret_cast<uintptr_t>(GV) | 0;
 145 }
 146
 147 static unsigned getAsmSymIndex(DataRefImpl Symb) {
 148   assert((Symb.p & uintptr_t(3)) == 3);
 149   uintptr_t Index = Symb.p & ~uintptr_t(3);
 150   Index >>= 2;
 151   return Index;
 152 }
 153
 154 void IRObjectFile::moveSymbolNext(DataRefImpl &Symb) const {
 155   const GlobalValue *GV = getGV(Symb);
 156   uintptr_t Res;
 157
 158   switch (Symb.p & 3) {
 159   case 0: {
 160     Module::const_iterator Iter(static_cast<const Function*>(GV));
 161     ++Iter;
 162     Res = skipEmpty(Iter, *M);
 163     break;
 164   }
 165   case 1: {
 166     Module::const_global_iterator Iter(static_cast<const GlobalVariable*>(GV));
 167     ++Iter;
 168     Res = skipEmpty(Iter, *M);
 169     break;
 170   }
 171   case 2: {
 172     Module::const_alias_iterator Iter(static_cast<const GlobalAlias*>(GV));
 173     ++Iter;
 174     Res = skipEmpty(Iter, *M);
 175     break;
 176   }
 177   case 3: {
 178     unsigned Index = getAsmSymIndex(Symb);
 179     assert(Index < AsmSymbols.size());
 180     ++Index;
 181     Res = (Index << 2) | 3;
 182     break;
 183   }
 184   default:
 185     llvm_unreachable("unreachable case");
 186   }
 187
 188   Symb.p = Res;
 189 }
 190
 191 std::error_code IRObjectFile::printSymbolName(raw_ostream &OS,
 192                                               DataRefImpl Symb) const {
 193   const GlobalValue *GV = getGV(Symb);
 194   if (!GV) {
 195     unsigned Index = getAsmSymIndex(Symb);
 196     assert(Index <= AsmSymbols.size());
 197     OS << AsmSymbols[Index].first;
 198     return object_error::success;;
 199   }
 200
 201   if (Mang)
 202     Mang->getNameWithPrefix(OS, GV, false);
 203   else
 204     OS << GV->getName();
 205
 206   return object_error::success;
 207 }
 208
 209 uint32_t IRObjectFile::getSymbolFlags(DataRefImpl Symb) const {
 210   const GlobalValue *GV = getGV(Symb);
 211
 212   if (!GV) {
 213     unsigned Index = getAsmSymIndex(Symb);
 214     assert(Index <= AsmSymbols.size());
 215     return AsmSymbols[Index].second;
 216   }
 217
 218   uint32_t Res = BasicSymbolRef::SF_None;
 219   if (GV->isDeclarationForLinker())
 220     Res |= BasicSymbolRef::SF_Undefined;
 221   if (GV->hasPrivateLinkage())
 222     Res |= BasicSymbolRef::SF_FormatSpecific;
 223   if (!GV->hasLocalLinkage())
 224     Res |= BasicSymbolRef::SF_Global;
 225   if (GV->hasCommonLinkage())
 226     Res |= BasicSymbolRef::SF_Common;
 227   if (GV->hasLinkOnceLinkage() || GV->hasWeakLinkage())
 228     Res |= BasicSymbolRef::SF_Weak;
 229
 230   if (GV->getName().startswith("llvm."))
 231     Res |= BasicSymbolRef::SF_FormatSpecific;
 232   else if (auto *Var = dyn_cast<GlobalVariable>(GV)) {
 233     if (Var->getSection() == StringRef("llvm.metadata"))
 234       Res |= BasicSymbolRef::SF_FormatSpecific;
 235   }
 236
 237   return Res;
 238 }
 239
 240 GlobalValue *IRObjectFile::getSymbolGV(DataRefImpl Symb) { return getGV(Symb); }
 241
 242 std::unique_ptr<Module> IRObjectFile::takeModule() { return std::move(M); }
 243
 244 basic_symbol_iterator IRObjectFile::symbol_begin_impl() const {
 245   Module::const_iterator I = M->begin();
 246   DataRefImpl Ret;
 247   Ret.p = skipEmpty(I, *M);
 248   return basic_symbol_iterator(BasicSymbolRef(Ret, this));
 249 }
 250
 251 basic_symbol_iterator IRObjectFile::symbol_end_impl() const {
 252   DataRefImpl Ret;
 253   uint64_t NumAsm = AsmSymbols.size();
 254   NumAsm <<= 2;
 255   Ret.p = 3 | NumAsm;
 256   return basic_symbol_iterator(BasicSymbolRef(Ret, this));
 257 }
 258
 259 ErrorOr<MemoryBufferRef> IRObjectFile::findBitcodeInObject(const ObjectFile &Obj) {
 260   for (const SectionRef &Sec : Obj.sections()) {
 261     StringRef SecName;
 262     if (std::error_code EC = Sec.getName(SecName))
 263       return EC;
 264     if (SecName == ".llvmbc") {
 265       StringRef SecContents;
 266       if (std::error_code EC = Sec.getContents(SecContents))
 267         return EC;
 268       return MemoryBufferRef(SecContents, Obj.getFileName());
 269     }
 270   }
 271
 272   return object_error::bitcode_section_not_found;
 273 }
 274
 275 ErrorOr<MemoryBufferRef> IRObjectFile::findBitcodeInMemBuffer(MemoryBufferRef Object) {
 276   sys::fs::file_magic Type = sys::fs::identify_magic(Object.getBuffer());
 277   switch (Type) {
 278   case sys::fs::file_magic::bitcode:
 279     return Object;
 280   case sys::fs::file_magic::elf_relocatable:
 281   case sys::fs::file_magic::macho_object:
 282   case sys::fs::file_magic::coff_object: {
 283     ErrorOr<std::unique_ptr<ObjectFile>> ObjFile =
 284         ObjectFile::createObjectFile(Object, Type);
 285     if (!ObjFile)
 286       return ObjFile.getError();
 287     return findBitcodeInObject(*ObjFile->get());
 288   }
 289   default:
 290     return object_error::invalid_file_type;
 291   }
 292 }
 293
 294 ErrorOr<std::unique_ptr<IRObjectFile>>
 295 llvm::object::IRObjectFile::create(MemoryBufferRef Object,
 296                                    LLVMContext &Context) {
 297   ErrorOr<MemoryBufferRef> BCOrErr = findBitcodeInMemBuffer(Object);
 298   if (!BCOrErr)
 299     return BCOrErr.getError();
 300
 301   std::unique_ptr<MemoryBuffer> Buff(
 302       MemoryBuffer::getMemBuffer(BCOrErr.get(), false));
 303
 304   ErrorOr<Module *> MOrErr = getLazyBitcodeModule(std::move(Buff), Context);
 305   if (std::error_code EC = MOrErr.getError())
 306     return EC;
 307
 308   std::unique_ptr<Module> M(MOrErr.get());
 309   return llvm::make_unique<IRObjectFile>(Object, std::move(M));
 310 }