Debug Info: Move isSubprogramContext from DebugInfo to DwarfDebug.

This helper function needs the type identifier map when we switch
DIType::getContext to return DIScopeRef instead of DIScope.

Since isSubprogramContext is used by DwarfDebug only, We move it to DwarfDebug
to have easy access to the map.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@190325 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/CodeGen/AsmPrinter/DwarfDebug.cpp b/lib/CodeGen/AsmPrinter/DwarfDebug.cpp
index 885d4ba..bdcb813 100644
--- a/lib/CodeGen/AsmPrinter/DwarfDebug.cpp
+++ b/lib/CodeGen/AsmPrinter/DwarfDebug.cpp
@@ -332,6 +332,19 @@
   }
 }
 
+/// isSubprogramContext - Return true if Context is either a subprogram
+/// or another context nested inside a subprogram.
+bool DwarfDebug::isSubprogramContext(const MDNode *Context) {
+  if (!Context)
+    return false;
+  DIDescriptor D(Context);
+  if (D.isSubprogram())
+    return true;
+  if (D.isType())
+    return isSubprogramContext(DIType(Context).getContext());
+  return false;
+}
+
 // Find DIE for the given subprogram and attach appropriate DW_AT_low_pc
 // and DW_AT_high_pc attributes. If there are global variables in this
 // scope then create and insert DIEs for these variables.