[StackMaps] Add a lightweight parser for stackmap version 1 sections.

The parser provides a convenient interface for reading llvm stackmap v1 sections
in object files.

This patch also includes a new option for llvm-readobj, '-stackmap', which uses
the parser to pretty-print stackmap sections for debugging/testing purposes.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@240860 91177308-0d34-0410-b5e6-96231b3b80d8

tools/llvm-readobj/llvm-readobj.cpp

@@ -176,6 +176,12 @@ namespace opts {
   cl::opt<bool>
   COFFBaseRelocs("coff-basereloc",
                  cl::desc("Display the PE/COFF .reloc section"));
+
+  // -stackmap
+  cl::opt<bool>
+  PrintStackMap("stackmap",
+                cl::desc("Display contents of stackmap section"));
+
 } // namespace opts
 
 static int ReturnValue = EXIT_SUCCESS;
@@ -316,6 +322,9 @@ static void dumpObject(const ObjectFile *Obj) {
     Dumper->printCOFFDirectives();
   if (opts::COFFBaseRelocs)
     Dumper->printCOFFBaseReloc();
+
+  if (opts::PrintStackMap)
+    Dumper->printStackMap();
 }
 
 /// @brief Dumps each object file in \a Arc;