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/ADT/STLExtras.h"
  17 #include "llvm/Bitcode/ReaderWriter.h"
  18 #include "llvm/IR/GVMaterializer.h"
  19 #include "llvm/IR/LLVMContext.h"
  20 #include "llvm/IR/Mangler.h"
  21 #include "llvm/IR/Module.h"
  22 #include "llvm/MC/MCAsmInfo.h"
  23 #include "llvm/MC/MCContext.h"
  24 #include "llvm/MC/MCInstrInfo.h"
  25 #include "llvm/MC/MCObjectFileInfo.h"
  26 #include "llvm/MC/MCParser/MCAsmParser.h"
  27 #include "llvm/MC/MCRegisterInfo.h"
  28 #include "llvm/MC/MCSubtargetInfo.h"
  29 #include "llvm/MC/MCTargetAsmParser.h"
  30 #include "llvm/Object/ObjectFile.h"
  31 #include "llvm/Support/MemoryBuffer.h"
  32 #include "llvm/Support/SourceMgr.h"
  33 #include "llvm/Support/TargetRegistry.h"
  34 #include "llvm/Support/raw_ostream.h"
  35 using namespace llvm;
  36 using namespace object;
  37
  38 IRObjectFile::IRObjectFile(MemoryBufferRef Object, std::unique_ptr<Module> Mod)
  39     : SymbolicFile(Binary::ID_IR, Object), M(std::move(Mod)) {
  40   Mang.reset(new Mangler());
  41
  42   const std::string &InlineAsm = M->getModuleInlineAsm();
  43   if (InlineAsm.empty())
  44     return;
  45
  46   Triple TT(M->getTargetTriple());
  47   std::string Err;
  48   const Target *T = TargetRegistry::lookupTarget(TT.str(), Err);
  49   if (!T)
  50     return;
  51
  52   std::unique_ptr<MCRegisterInfo> MRI(T->createMCRegInfo(TT.str()));
  53   if (!MRI)
  54     return;
  55
  56   std::unique_ptr<MCAsmInfo> MAI(T->createMCAsmInfo(*MRI, TT.str()));
  57   if (!MAI)
  58     return;
  59
  60   std::unique_ptr<MCSubtargetInfo> STI(
  61       T->createMCSubtargetInfo(TT.str(), "", ""));
  62   if (!STI)
  63     return;
  64
  65   std::unique_ptr<MCInstrInfo> MCII(T->createMCInstrInfo());
  66   if (!MCII)
  67     return;
  68
  69   MCObjectFileInfo MOFI;
  70   MCContext MCCtx(MAI.get(), MRI.get(), &MOFI);
  71   MOFI.InitMCObjectFileInfo(TT, Reloc::Default, CodeModel::Default, MCCtx);
  72   std::unique_ptr<RecordStreamer> Streamer(new RecordStreamer(MCCtx));
  73   T->createNullTargetStreamer(*Streamer);
  74
  75   std::unique_ptr<MemoryBuffer> Buffer(MemoryBuffer::getMemBuffer(InlineAsm));
  76   SourceMgr SrcMgr;
  77   SrcMgr.AddNewSourceBuffer(std::move(Buffer), SMLoc());
  78   std::unique_ptr<MCAsmParser> Parser(
  79       createMCAsmParser(SrcMgr, MCCtx, *Streamer, *MAI));
  80
  81   MCTargetOptions MCOptions;
  82   std::unique_ptr<MCTargetAsmParser> TAP(
  83       T->createMCAsmParser(*STI, *Parser, *MCII, MCOptions));
  84   if (!TAP)
  85     return;
  86
  87   Parser->setTargetParser(*TAP);
  88   if (Parser->Run(false))
  89     return;
  90
  91   for (auto &KV : *Streamer) {
  92     StringRef Key = KV.first();
  93     RecordStreamer::State Value = KV.second;
  94     uint32_t Res = BasicSymbolRef::SF_None;
  95     switch (Value) {
  96     case RecordStreamer::NeverSeen:
  97       llvm_unreachable("foo");
  98     case RecordStreamer::DefinedGlobal:
  99       Res |= BasicSymbolRef::SF_Global;
 100       break;
 101     case RecordStreamer::Defined:
 102       break;
 103     case RecordStreamer::Global:
 104     case RecordStreamer::Used:
 105       Res |= BasicSymbolRef::SF_Undefined;
 106       Res |= BasicSymbolRef::SF_Global;
 107       break;
 108     }
 109     AsmSymbols.push_back(
 110         std::make_pair<std::string, uint32_t>(Key, std::move(Res)));
 111   }
 112 }
 113
 114 IRObjectFile::~IRObjectFile() {
 115  }
 116
 117 static GlobalValue *getGV(DataRefImpl &Symb) {
 118   if ((Symb.p & 3) == 3)
 119     return nullptr;
 120
 121   return reinterpret_cast<GlobalValue*>(Symb.p & ~uintptr_t(3));
 122 }
 123
 124 static uintptr_t skipEmpty(Module::const_alias_iterator I, const Module &M) {
 125   if (I == M.alias_end())
 126     return 3;
 127   const GlobalValue *GV = &*I;
 128   return reinterpret_cast<uintptr_t>(GV) | 2;
 129 }
 130
 131 static uintptr_t skipEmpty(Module::const_global_iterator I, const Module &M) {
 132   if (I == M.global_end())
 133     return skipEmpty(M.alias_begin(), M);
 134   const GlobalValue *GV = &*I;
 135   return reinterpret_cast<uintptr_t>(GV) | 1;
 136 }
 137
 138 static uintptr_t skipEmpty(Module::const_iterator I, const Module &M) {
 139   if (I == M.end())
 140     return skipEmpty(M.global_begin(), M);
 141   const GlobalValue *GV = &*I;
 142   return reinterpret_cast<uintptr_t>(GV) | 0;
 143 }
 144
 145 static unsigned getAsmSymIndex(DataRefImpl Symb) {
 146   assert((Symb.p & uintptr_t(3)) == 3);
 147   uintptr_t Index = Symb.p & ~uintptr_t(3);
 148   Index >>= 2;
 149   return Index;
 150 }
 151
 152 void IRObjectFile::moveSymbolNext(DataRefImpl &Symb) const {
 153   const GlobalValue *GV = getGV(Symb);
 154   uintptr_t Res;
 155
 156   switch (Symb.p & 3) {
 157   case 0: {
 158     Module::const_iterator Iter(static_cast<const Function*>(GV));
 159     ++Iter;
 160     Res = skipEmpty(Iter, *M);
 161     break;
 162   }
 163   case 1: {
 164     Module::const_global_iterator Iter(static_cast<const GlobalVariable*>(GV));
 165     ++Iter;
 166     Res = skipEmpty(Iter, *M);
 167     break;
 168   }
 169   case 2: {
 170     Module::const_alias_iterator Iter(static_cast<const GlobalAlias*>(GV));
 171     ++Iter;
 172     Res = skipEmpty(Iter, *M);
 173     break;
 174   }
 175   case 3: {
 176     unsigned Index = getAsmSymIndex(Symb);
 177     assert(Index < AsmSymbols.size());
 178     ++Index;
 179     Res = (Index << 2) | 3;
 180     break;
 181   }
 182   default:
 183     llvm_unreachable("unreachable case");
 184   }
 185
 186   Symb.p = Res;
 187 }
 188
 189 std::error_code IRObjectFile::printSymbolName(raw_ostream &OS,
 190                                               DataRefImpl Symb) const {
 191   const GlobalValue *GV = getGV(Symb);
 192   if (!GV) {
 193     unsigned Index = getAsmSymIndex(Symb);
 194     assert(Index <= AsmSymbols.size());
 195     OS << AsmSymbols[Index].first;
 196     return std::error_code();
 197   }
 198
 199   if (GV->hasDLLImportStorageClass())
 200     OS << "__imp_";
 201
 202   if (Mang)
 203     Mang->getNameWithPrefix(OS, GV, false);
 204   else
 205     OS << GV->getName();
 206
 207   return std::error_code();
 208 }
 209
 210 uint32_t IRObjectFile::getSymbolFlags(DataRefImpl Symb) const {
 211   const GlobalValue *GV = getGV(Symb);
 212
 213   if (!GV) {
 214     unsigned Index = getAsmSymIndex(Symb);
 215     assert(Index <= AsmSymbols.size());
 216     return AsmSymbols[Index].second;
 217   }
 218
 219   uint32_t Res = BasicSymbolRef::SF_None;
 220   if (GV->isDeclarationForLinker())
 221     Res |= BasicSymbolRef::SF_Undefined;
 222   else if (GV->hasHiddenVisibility() && !GV->hasLocalLinkage())
 223     Res |= BasicSymbolRef::SF_Hidden;
 224   if (const GlobalVariable *GVar = dyn_cast<GlobalVariable>(GV)) {
 225     if (GVar->isConstant())
 226       Res |= BasicSymbolRef::SF_Const;
 227   }
 228   if (GV->hasPrivateLinkage())
 229     Res |= BasicSymbolRef::SF_FormatSpecific;
 230   if (!GV->hasLocalLinkage())
 231     Res |= BasicSymbolRef::SF_Global;
 232   if (GV->hasCommonLinkage())
 233     Res |= BasicSymbolRef::SF_Common;
 234   if (GV->hasLinkOnceLinkage() || GV->hasWeakLinkage())
 235     Res |= BasicSymbolRef::SF_Weak;
 236
 237   if (GV->getName().startswith("llvm."))
 238     Res |= BasicSymbolRef::SF_FormatSpecific;
 239   else if (auto *Var = dyn_cast<GlobalVariable>(GV)) {
 240     if (Var->getSection() == StringRef("llvm.metadata"))
 241       Res |= BasicSymbolRef::SF_FormatSpecific;
 242   }
 243
 244   return Res;
 245 }
 246
 247 GlobalValue *IRObjectFile::getSymbolGV(DataRefImpl Symb) { return getGV(Symb); }
 248
 249 std::unique_ptr<Module> IRObjectFile::takeModule() { return std::move(M); }
 250
 251 basic_symbol_iterator IRObjectFile::symbol_begin_impl() const {
 252   Module::const_iterator I = M->begin();
 253   DataRefImpl Ret;
 254   Ret.p = skipEmpty(I, *M);
 255   return basic_symbol_iterator(BasicSymbolRef(Ret, this));
 256 }
 257
 258 basic_symbol_iterator IRObjectFile::symbol_end_impl() const {
 259   DataRefImpl Ret;
 260   uint64_t NumAsm = AsmSymbols.size();
 261   NumAsm <<= 2;
 262   Ret.p = 3 | NumAsm;
 263   return basic_symbol_iterator(BasicSymbolRef(Ret, this));
 264 }
 265
 266 ErrorOr<MemoryBufferRef> IRObjectFile::findBitcodeInObject(const ObjectFile &Obj) {
 267   for (const SectionRef &Sec : Obj.sections()) {
 268     StringRef SecName;
 269     if (std::error_code EC = Sec.getName(SecName))
 270       return EC;
 271     if (SecName == ".llvmbc") {
 272       StringRef SecContents;
 273       if (std::error_code EC = Sec.getContents(SecContents))
 274         return EC;
 275       return MemoryBufferRef(SecContents, Obj.getFileName());
 276     }
 277   }
 278
 279   return object_error::bitcode_section_not_found;
 280 }
 281
 282 ErrorOr<MemoryBufferRef> IRObjectFile::findBitcodeInMemBuffer(MemoryBufferRef Object) {
 283   sys::fs::file_magic Type = sys::fs::identify_magic(Object.getBuffer());
 284   switch (Type) {
 285   case sys::fs::file_magic::bitcode:
 286     return Object;
 287   case sys::fs::file_magic::elf_relocatable:
 288   case sys::fs::file_magic::macho_object:
 289   case sys::fs::file_magic::coff_object: {
 290     ErrorOr<std::unique_ptr<ObjectFile>> ObjFile =
 291         ObjectFile::createObjectFile(Object, Type);
 292     if (!ObjFile)
 293       return ObjFile.getError();
 294     return findBitcodeInObject(*ObjFile->get());
 295   }
 296   default:
 297     return object_error::invalid_file_type;
 298   }
 299 }
 300
 301 ErrorOr<std::unique_ptr<IRObjectFile>>
 302 llvm::object::IRObjectFile::create(MemoryBufferRef Object,
 303                                    LLVMContext &Context) {
 304   ErrorOr<MemoryBufferRef> BCOrErr = findBitcodeInMemBuffer(Object);
 305   if (!BCOrErr)
 306     return BCOrErr.getError();
 307
 308   std::unique_ptr<MemoryBuffer> Buff(
 309       MemoryBuffer::getMemBuffer(BCOrErr.get(), false));
 310
 311   ErrorOr<std::unique_ptr<Module>> MOrErr =
 312       getLazyBitcodeModule(std::move(Buff), Context, nullptr,
 313                            /*ShouldLazyLoadMetadata*/ true);
 314   if (std::error_code EC = MOrErr.getError())
 315     return EC;
 316
 317   std::unique_ptr<Module> &M = MOrErr.get();
 318   return llvm::make_unique<IRObjectFile>(Object, std::move(M));
 319 }