1 files changed, 53 insertions, 0 deletions
diff --git a/include/lld/Core/SharedLibraryAtom.h b/include/lld/Core/SharedLibraryAtom.h
new file mode 100644
index 000000000000..1b0c37c41138
--- /dev/null
+++ b/include/lld/Core/SharedLibraryAtom.h
@@ -0,0 +1,53 @@
+//===- Core/SharedLibraryAtom.h - A Shared Library Atom -------------------===//
+//
+//                             The LLVM Linker
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLD_CORE_SHARED_LIBRARY_ATOM_H
+#define LLD_CORE_SHARED_LIBRARY_ATOM_H
+
+#include "lld/Core/Atom.h"
+
+namespace lld {
+
+/// A SharedLibraryAtom has no content.
+/// It exists to represent a symbol which will be bound at runtime.
+class SharedLibraryAtom : public Atom {
+public:
+  enum class Type : uint32_t {
+    Unknown,
+    Code,
+    Data,
+  };
+
+  /// Returns shared library name used to load it at runtime.
+  /// On linux that is the DT_NEEDED name.
+  /// On Darwin it is the LC_DYLIB_LOAD dylib name.
+  /// On Windows it is the DLL name that to be referred from .idata section.
+  virtual StringRef loadName() const = 0;
+
+  /// Returns if shared library symbol can be missing at runtime and if
+  /// so the loader should silently resolve address of symbol to be nullptr.
+  virtual bool canBeNullAtRuntime() const = 0;
+
+  virtual Type type() const = 0;
+
+  virtual uint64_t size() const = 0;
+
+  static bool classof(const Atom *a) {
+    return a->definition() == definitionSharedLibrary;
+  }
+
+  static inline bool classof(const SharedLibraryAtom *) { return true; }
+
+protected:
+  SharedLibraryAtom() : Atom(definitionSharedLibrary) {}
+};
+
+} // namespace lld
+
+#endif // LLD_CORE_SHARED_LIBRARY_ATOM_H