dwarfdump: First piece of support for DWP dumping

Just a tiny piece of index dumping - the header in this instance.

llvm-svn: 252781
diff --git a/llvm/lib/DebugInfo/DWARF/DWARFContext.cpp b/llvm/lib/DebugInfo/DWARF/DWARFContext.cpp
index aecd991..7ece678 100644
--- a/llvm/lib/DebugInfo/DWARF/DWARFContext.cpp
+++ b/llvm/lib/DebugInfo/DWARF/DWARFContext.cpp
@@ -12,6 +12,7 @@
 #include "llvm/ADT/StringSwitch.h"
 #include "llvm/DebugInfo/DWARF/DWARFAcceleratorTable.h"
 #include "llvm/DebugInfo/DWARF/DWARFDebugArangeSet.h"
+#include "llvm/DebugInfo/DWARF/DWARFUnitIndex.h"
 #include "llvm/Support/Compression.h"
 #include "llvm/Support/Dwarf.h"
 #include "llvm/Support/Format.h"
@@ -155,6 +156,14 @@
     }
   }
 
+  if (DumpType == DIDT_All || DumpType == DIDT_CUIndex) {
+    OS << "\n.debug_cu_index contents:\n";
+    DataExtractor CUIndexData(getCUIndexSection(), isLittleEndian(), savedAddressByteSize);
+    DWARFUnitIndex CUIndex;
+    CUIndex.parse(CUIndexData);
+    CUIndex.dump(OS);
+  }
+
   if (DumpType == DIDT_All || DumpType == DIDT_LineDwo) {
     OS << "\n.debug_line.dwo contents:\n";
     unsigned stmtOffset = 0;
@@ -608,6 +617,7 @@
             .Case("apple_namespaces", &AppleNamespacesSection.Data)
             .Case("apple_namespac", &AppleNamespacesSection.Data)
             .Case("apple_objc", &AppleObjCSection.Data)
+            .Case("debug_cu_index", &CUIndexSection)
             // Any more debug info sections go here.
             .Default(nullptr);
     if (SectionData) {