[PATCH] Add explictly exported atoms and export R_*_COPY'ed atoms.

[kledzik at apple.com]

  LGTM


================
Comment at: include/lld/Core/DefinedAtom.h:189
@@ +188,3 @@
+  enum DynamicExport {
+    /// \brief The linker may or may not export this atom dynamicly depending on
+    ///   the output type and other context of the link.
----------------
dynamically

================
Comment at: include/lld/Core/DefinedAtom.h:263
@@ -254,1 +262,3 @@
 
+  /// \brief Under which conditions should this atom be dynamicly exported.
+  virtual DynamicExport dynamicExport() const {
----------------
dynamically

================
Comment at: lib/ReaderWriter/ELF/OutputELFWriter.h:157-158
@@ +156,4 @@
+      for (const auto &atom : section->atoms()) {
+        const DefinedAtom *da = dyn_cast<const DefinedAtom>(atom->_atom);
+        if (da && da->dynamicExport() == DefinedAtom::dynamicExportAlways)
+          _dynamicSymbolTable->addSymbol(atom->_atom, section->ordinal(),
----------------
if (const DefinedAtom *da = dyn_cast<const DefinedAtom>(atom->_atom)) {
if (da->dynamicExport() == DefinedAtom::dynamicExportAlways))

gets rid of the "da &&"


http://llvm-reviews.chandlerc.com/D1799