[mach-o] Add support for parsing __eh_frame section. Generalize support for whether symbols in a section are ignored or illegal

llvm-svn: 209858
diff --git a/lld/lib/ReaderWriter/MachO/MachONormalizedFileFromAtoms.cpp b/lld/lib/ReaderWriter/MachO/MachONormalizedFileFromAtoms.cpp
index 6531455..00aabc2 100644
--- a/lld/lib/ReaderWriter/MachO/MachONormalizedFileFromAtoms.cpp
+++ b/lld/lib/ReaderWriter/MachO/MachONormalizedFileFromAtoms.cpp
@@ -200,6 +200,9 @@
   case DefinedAtom::typeCFString:
      return new (_allocator) SectionInfo("__DATA", "__cfstring",
                             S_REGULAR);
+  case DefinedAtom::typeCFI:
+     return new (_allocator) SectionInfo("__TEXT", "__eh_frame",
+                            S_COALESCED);
   default:
     llvm_unreachable("TO DO: add support for more sections");
     break;