llvm-readobj: add support to dump (COFF) directives

PE/COFF has a special section (.drectve) which can be used to pass options to
the linker (similar to LC_LINKER_OPTION).  Add support to llvm-readobj to print
the contents of the section for tests.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@219228 91177308-0d34-0410-b5e6-96231b3b80d8

tools/llvm-readobj/llvm-readobj.cpp

@@ -145,6 +145,11 @@ namespace opts {
   // -coff-imports
   cl::opt<bool>
   COFFImports("coff-imports", cl::desc("Display the PE/COFF import table"));
+
+  // -coff-directives
+  cl::opt<bool>
+  COFFDirectives("coff-directives",
+                 cl::desc("Display the contents PE/COFF .drectve section"));
 } // namespace opts
 
 static int ReturnValue = EXIT_SUCCESS;
@@ -272,6 +277,8 @@ static void dumpObject(const ObjectFile *Obj) {
       Dumper->printMipsPLTGOT();
   if (opts::COFFImports)
     Dumper->printCOFFImports();
+  if (opts::COFFDirectives)
+    Dumper->printCOFFDirectives();
 }