1 files changed, 148 insertions, 0 deletions
diff --git a/ELF/Symbols.cpp b/ELF/Symbols.cpp
new file mode 100644
index 000000000000..f8d585242a86
--- /dev/null
+++ b/ELF/Symbols.cpp
@@ -0,0 +1,148 @@
+//===- Symbols.cpp --------------------------------------------------------===//
+//
+//                             The LLVM Linker
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+
+#include "Symbols.h"
+#include "InputSection.h"
+#include "Error.h"
+#include "InputFiles.h"
+
+#include "llvm/ADT/STLExtras.h"
+
+using namespace llvm;
+using namespace llvm::object;
+using namespace llvm::ELF;
+
+using namespace lld;
+using namespace lld::elf2;
+
+static uint8_t getMinVisibility(uint8_t VA, uint8_t VB) {
+  if (VA == STV_DEFAULT)
+    return VB;
+  if (VB == STV_DEFAULT)
+    return VA;
+  return std::min(VA, VB);
+}
+
+// Returns 1, 0 or -1 if this symbol should take precedence
+// over the Other, tie or lose, respectively.
+template <class ELFT> int SymbolBody::compare(SymbolBody *Other) {
+  typedef typename ELFFile<ELFT>::uintX_t uintX_t;
+  assert(!isLazy() && !Other->isLazy());
+  std::pair<bool, bool> L(isDefined(), !isWeak());
+  std::pair<bool, bool> R(Other->isDefined(), !Other->isWeak());
+
+  // Normalize
+  if (L > R)
+    return -Other->compare<ELFT>(this);
+
+  Visibility = Other->Visibility =
+      getMinVisibility(Visibility, Other->Visibility);
+
+  if (IsUsedInRegularObj || Other->IsUsedInRegularObj)
+    IsUsedInRegularObj = Other->IsUsedInRegularObj = true;
+
+  if (L != R)
+    return -1;
+  if (!L.first || !L.second)
+    return 1;
+  if (isShared())
+    return -1;
+  if (Other->isShared())
+    return 1;
+  if (isCommon()) {
+    if (!Other->isCommon())
+      return -1;
+    auto *ThisC = cast<DefinedCommon>(this);
+    auto *OtherC = cast<DefinedCommon>(Other);
+    uintX_t Align = std::max(ThisC->MaxAlignment, OtherC->MaxAlignment);
+    if (ThisC->Size >= OtherC->Size) {
+      ThisC->MaxAlignment = Align;
+      return 1;
+    }
+    OtherC->MaxAlignment = Align;
+    return -1;
+  }
+  if (Other->isCommon())
+    return 1;
+  return 0;
+}
+
+Defined::Defined(Kind K, StringRef Name, bool IsWeak, uint8_t Visibility,
+                 bool IsTls)
+    : SymbolBody(K, Name, IsWeak, Visibility, IsTls) {}
+
+Undefined::Undefined(SymbolBody::Kind K, StringRef N, bool IsWeak,
+                     uint8_t Visibility, bool IsTls)
+    : SymbolBody(K, N, IsWeak, Visibility, IsTls), CanKeepUndefined(false) {}
+
+Undefined::Undefined(StringRef N, bool IsWeak, uint8_t Visibility,
+                     bool CanKeepUndefined)
+    : Undefined(SymbolBody::UndefinedKind, N, IsWeak, Visibility,
+                /*IsTls*/ false) {
+  this->CanKeepUndefined = CanKeepUndefined;
+}
+
+template <typename ELFT>
+UndefinedElf<ELFT>::UndefinedElf(StringRef N, const Elf_Sym &Sym)
+    : Undefined(SymbolBody::UndefinedElfKind, N,
+                Sym.getBinding() == llvm::ELF::STB_WEAK, Sym.getVisibility(),
+                Sym.getType() == llvm::ELF::STT_TLS),
+      Sym(Sym) {}
+
+template <typename ELFT>
+DefinedSynthetic<ELFT>::DefinedSynthetic(StringRef N, uintX_t Value,
+                                         OutputSectionBase<ELFT> &Section)
+    : Defined(SymbolBody::DefinedSyntheticKind, N, false, STV_DEFAULT, false),
+      Value(Value), Section(Section) {}
+
+DefinedCommon::DefinedCommon(StringRef N, uint64_t Size, uint64_t Alignment,
+                             bool IsWeak, uint8_t Visibility)
+    : Defined(SymbolBody::DefinedCommonKind, N, IsWeak, Visibility, false) {
+  MaxAlignment = Alignment;
+  this->Size = Size;
+}
+
+std::unique_ptr<InputFile> Lazy::getMember() {
+  MemoryBufferRef MBRef = File->getMember(&Sym);
+
+  // getMember returns an empty buffer if the member was already
+  // read from the library.
+  if (MBRef.getBuffer().empty())
+    return std::unique_ptr<InputFile>(nullptr);
+
+  return createELFFile<ObjectFile>(MBRef);
+}
+
+template <class ELFT> static void doInitSymbols() {
+  ElfSym<ELFT>::End.setBinding(STB_GLOBAL);
+  ElfSym<ELFT>::IgnoreUndef.setBinding(STB_WEAK);
+  ElfSym<ELFT>::IgnoreUndef.setVisibility(STV_HIDDEN);
+}
+
+void lld::elf2::initSymbols() {
+  doInitSymbols<ELF32LE>();
+  doInitSymbols<ELF32BE>();
+  doInitSymbols<ELF64LE>();
+  doInitSymbols<ELF64BE>();
+}
+
+template int SymbolBody::compare<ELF32LE>(SymbolBody *Other);
+template int SymbolBody::compare<ELF32BE>(SymbolBody *Other);
+template int SymbolBody::compare<ELF64LE>(SymbolBody *Other);
+template int SymbolBody::compare<ELF64BE>(SymbolBody *Other);
+
+template class lld::elf2::UndefinedElf<ELF32LE>;
+template class lld::elf2::UndefinedElf<ELF32BE>;
+template class lld::elf2::UndefinedElf<ELF64LE>;
+template class lld::elf2::UndefinedElf<ELF64BE>;
+
+template class lld::elf2::DefinedSynthetic<ELF32LE>;
+template class lld::elf2::DefinedSynthetic<ELF32BE>;
+template class lld::elf2::DefinedSynthetic<ELF64LE>;
+template class lld::elf2::DefinedSynthetic<ELF64BE>;