1 files changed, 320 insertions, 0 deletions
diff --git a/lld/lib/ReaderWriter/CoreLinkingContext.cpp b/lld/lib/ReaderWriter/CoreLinkingContext.cpp
new file mode 100644
index 00000000000..8c7b0b76324
--- /dev/null
+++ b/lld/lib/ReaderWriter/CoreLinkingContext.cpp
@@ -0,0 +1,320 @@
+//===- lib/ReaderWriter/CoreLinkingContext.cpp ----------------------------===//
+//
+//                             The LLVM Linker
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+
+#include "lld/ReaderWriter/CoreLinkingContext.h"
+
+#include "lld/Core/Pass.h"
+#include "lld/Core/PassManager.h"
+#include "lld/Passes/LayoutPass.h"
+
+#include "llvm/ADT/ArrayRef.h"
+
+using namespace lld;
+
+namespace {
+
+/// \brief Simple atom created by the stubs pass.
+class TestingStubAtom : public DefinedAtom {
+public:
+  TestingStubAtom(const File &F, const Atom &) : _file(F) {
+    static uint32_t lastOrdinal = 0;
+    _ordinal = lastOrdinal++;
+  }
+
+  virtual const File &file() const { return _file; }
+
+  virtual StringRef name() const { return StringRef(); }
+
+  virtual uint64_t ordinal() const { return _ordinal; }
+
+  virtual uint64_t size() const { return 0; }
+
+  virtual Scope scope() const { return DefinedAtom::scopeLinkageUnit; }
+
+  virtual Interposable interposable() const { return DefinedAtom::interposeNo; }
+
+  virtual Merge merge() const { return DefinedAtom::mergeNo; }
+
+  virtual ContentType contentType() const { return DefinedAtom::typeStub; }
+
+  virtual Alignment alignment() const { return Alignment(0, 0); }
+
+  virtual SectionChoice sectionChoice() const {
+    return DefinedAtom::sectionBasedOnContent;
+  }
+
+  virtual StringRef customSectionName() const { return StringRef(); }
+
+  virtual SectionPosition sectionPosition() const { return sectionPositionAny; }
+
+  virtual DeadStripKind deadStrip() const {
+    return DefinedAtom::deadStripNormal;
+  }
+
+  virtual ContentPermissions permissions() const {
+    return DefinedAtom::permR_X;
+  }
+
+  virtual bool isAlias() const { return false; }
+
+  virtual ArrayRef<uint8_t> rawContent() const { return ArrayRef<uint8_t>(); }
+
+  virtual reference_iterator begin() const {
+    return reference_iterator(*this, nullptr);
+  }
+
+  virtual reference_iterator end() const {
+    return reference_iterator(*this, nullptr);
+  }
+
+  virtual const Reference *derefIterator(const void *iter) const {
+    return nullptr;
+  }
+
+  virtual void incrementIterator(const void *&iter) const {}
+
+private:
+  const File &_file;
+  uint32_t _ordinal;
+};
+
+/// \brief Simple atom created by the GOT pass.
+class TestingGOTAtom : public DefinedAtom {
+public:
+  TestingGOTAtom(const File &F, const Atom &) : _file(F) {
+    static uint32_t lastOrdinal = 0;
+    _ordinal = lastOrdinal++;
+  }
+
+  virtual const File &file() const { return _file; }
+
+  virtual StringRef name() const { return StringRef(); }
+
+  virtual uint64_t ordinal() const { return _ordinal; }
+
+  virtual uint64_t size() const { return 0; }
+
+  virtual Scope scope() const { return DefinedAtom::scopeLinkageUnit; }
+
+  virtual Interposable interposable() const { return DefinedAtom::interposeNo; }
+
+  virtual Merge merge() const { return DefinedAtom::mergeNo; }
+
+  virtual ContentType contentType() const { return DefinedAtom::typeGOT; }
+
+  virtual Alignment alignment() const { return Alignment(3, 0); }
+
+  virtual SectionChoice sectionChoice() const {
+    return DefinedAtom::sectionBasedOnContent;
+  }
+
+  virtual StringRef customSectionName() const { return StringRef(); }
+
+  virtual SectionPosition sectionPosition() const { return sectionPositionAny; }
+
+  virtual DeadStripKind deadStrip() const {
+    return DefinedAtom::deadStripNormal;
+  }
+
+  virtual ContentPermissions permissions() const {
+    return DefinedAtom::permRW_;
+  }
+
+  virtual bool isAlias() const { return false; }
+
+  virtual ArrayRef<uint8_t> rawContent() const { return ArrayRef<uint8_t>(); }
+
+  virtual reference_iterator begin() const {
+    return reference_iterator(*this, nullptr);
+  }
+
+  virtual reference_iterator end() const {
+    return reference_iterator(*this, nullptr);
+  }
+
+  virtual const Reference *derefIterator(const void *iter) const {
+    return nullptr;
+  }
+
+  virtual void incrementIterator(const void *&iter) const {}
+
+private:
+  const File &_file;
+  uint32_t _ordinal;
+};
+
+class TestingPassFile : public MutableFile {
+public:
+  TestingPassFile(const LinkingContext &ti) : MutableFile(ti, "Testing pass") {}
+
+  virtual void addAtom(const Atom &atom) {
+    if (const DefinedAtom *defAtom = dyn_cast<DefinedAtom>(&atom))
+      _definedAtoms._atoms.push_back(defAtom);
+    else
+      llvm_unreachable("atom has unknown definition kind");
+  }
+
+  virtual DefinedAtomRange definedAtoms() {
+    return range<std::vector<const DefinedAtom *>::iterator>(
+        _definedAtoms._atoms.begin(), _definedAtoms._atoms.end());
+  }
+
+  virtual const atom_collection<DefinedAtom> &defined() const {
+    return _definedAtoms;
+  }
+  virtual const atom_collection<UndefinedAtom> &undefined() const {
+    return _undefinedAtoms;
+  }
+  virtual const atom_collection<SharedLibraryAtom> &sharedLibrary() const {
+    return _sharedLibraryAtoms;
+  }
+  virtual const atom_collection<AbsoluteAtom> &absolute() const {
+    return _absoluteAtoms;
+  }
+
+private:
+  atom_collection_vector<DefinedAtom> _definedAtoms;
+  atom_collection_vector<UndefinedAtom> _undefinedAtoms;
+  atom_collection_vector<SharedLibraryAtom> _sharedLibraryAtoms;
+  atom_collection_vector<AbsoluteAtom> _absoluteAtoms;
+};
+
+struct TestingKindMapping {
+  const char *string;
+  int32_t value;
+  bool isBranch;
+  bool isGotLoad;
+  bool isGotUse;
+};
+
+//
+// Table of fixup kinds in YAML documents used for testing
+//
+const TestingKindMapping sKinds[] = {
+  { "in-group", -3, false, false, false },
+  { "layout-after", -2, false, false, false },
+  { "layout-before", -1, false, false, false },
+  { "call32", 2, true, false, false }, { "pcrel32", 3, false, false, false },
+  { "gotLoad32", 7, false, true, true }, { "gotUse32", 9, false, false, true },
+  { "lea32wasGot", 8, false, false, false }, { nullptr, 0, false, false, false }
+};
+
+class TestingStubsPass : public StubsPass {
+public:
+  TestingStubsPass(const LinkingContext &ti) : _file(TestingPassFile(ti)) {}
+
+  virtual bool noTextRelocs() { return true; }
+
+  virtual bool isCallSite(int32_t kind) {
+    for (const TestingKindMapping *p = sKinds; p->string != nullptr; ++p) {
+      if (kind == p->value)
+        return p->isBranch;
+    }
+    return false;
+  }
+
+  virtual const DefinedAtom *getStub(const Atom &target) {
+    const DefinedAtom *result = new TestingStubAtom(_file, target);
+    _file.addAtom(*result);
+    return result;
+  }
+
+  virtual void addStubAtoms(MutableFile &mergedFile) {
+    for (const DefinedAtom *stub : _file.defined()) {
+      mergedFile.addAtom(*stub);
+    }
+  }
+
+private:
+  TestingPassFile _file;
+};
+
+class TestingGOTPass : public GOTPass {
+public:
+  TestingGOTPass(const LinkingContext &ti) : _file(TestingPassFile(ti)) {}
+
+  virtual bool noTextRelocs() { return true; }
+
+  virtual bool isGOTAccess(int32_t kind, bool &canBypassGOT) {
+    for (const TestingKindMapping *p = sKinds; p->string != nullptr; ++p) {
+      if (kind == p->value) {
+        canBypassGOT = p->isGotLoad;
+        return p->isGotUse || p->isGotLoad;
+      }
+    }
+    return false;
+  }
+
+  virtual void updateReferenceToGOT(const Reference *ref, bool targetIsNowGOT) {
+    if (targetIsNowGOT)
+      const_cast<Reference *>(ref)->setKind(3); // pcrel32
+    else
+      const_cast<Reference *>(ref)->setKind(8); // lea32wasGot
+  }
+
+  virtual const DefinedAtom *makeGOTEntry(const Atom &target) {
+    return new TestingGOTAtom(_file, target);
+  }
+
+private:
+  TestingPassFile _file;
+};
+
+} // anonymous namespace
+
+CoreLinkingContext::CoreLinkingContext() {}
+
+bool CoreLinkingContext::validateImpl(raw_ostream &diagnostics) {
+  return false;
+}
+
+void CoreLinkingContext::addPasses(PassManager &pm) const {
+  for (StringRef name : _passNames) {
+    if (name.equals("layout"))
+      pm.add(std::unique_ptr<Pass>((new LayoutPass())));
+    else if (name.equals("GOT"))
+      pm.add(std::unique_ptr<Pass>(new TestingGOTPass(*this)));
+    else if (name.equals("stubs"))
+      pm.add(std::unique_ptr<Pass>(new TestingStubsPass(*this)));
+    else
+      llvm_unreachable("bad pass name");
+  }
+}
+
+error_code CoreLinkingContext::parseFile(
+    std::unique_ptr<MemoryBuffer> &mb,
+    std::vector<std::unique_ptr<File>> &result) const {
+  if (!_reader)
+    _reader = createReaderYAML(*this);
+  return _reader->parseFile(mb, result);
+}
+
+Writer &CoreLinkingContext::writer() const {
+  if (!_writer)
+    _writer = createWriterYAML(*this);
+  return *_writer;
+}
+
+ErrorOr<Reference::Kind>
+CoreLinkingContext::relocKindFromString(StringRef str) const {
+  for (const TestingKindMapping *p = sKinds; p->string != nullptr; ++p) {
+    if (str.equals(p->string))
+      return p->value;
+  }
+  return make_error_code(yaml_reader_error::illegal_value);
+}
+
+ErrorOr<std::string>
+CoreLinkingContext::stringFromRelocKind(Reference::Kind kind) const {
+  for (const TestingKindMapping *p = sKinds; p->string != nullptr; ++p) {
+    if (kind == p->value)
+      return std::string(p->string);
+  }
+  return make_error_code(yaml_reader_error::illegal_value);
+}