Add basic support for .debug_ranges section to LLVM's DebugInfo library.

This section (introduced in DWARF-3) is used to define instruction address
ranges for functions that are not contiguous and can't be described
by low_pc/high_pc attributes (this is the usual case for inlined subroutines).
The patch is the first step to support fetching complete inlining info from DWARF.

Reviewed by Benjamin Kramer.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@162657 91177308-0d34-0410-b5e6-96231b3b80d8

include/llvm/DebugInfo/DIContext.h

@@ -81,7 +81,8 @@ public:
                                     StringRef abbrevSection,
                                     StringRef aRangeSection = StringRef(),
                                     StringRef lineSection = StringRef(),
-                                    StringRef stringSection = StringRef());
+                                    StringRef stringSection = StringRef(),
+                                    StringRef rangeSection = StringRef());
 
   virtual void dump(raw_ostream &OS) = 0;