Index: include/llvm/Support/Debug.h
===================================================================
--- include/llvm/Support/Debug.h
+++ include/llvm/Support/Debug.h
@@ -51,6 +51,12 @@
 ///
 void setCurrentDebugType(const char *Type);
 
+/// setCurrentDebugTypes - Set the current debug type, as if the
+/// -debug-only=X,Y,Z option were specified. Note that DebugFlag
+/// also needs to be set to true for debug output to be produced.
+///
+void setCurrentDebugTypes(const char **Types, unsigned Count);
+
 /// DEBUG_WITH_TYPE macro - This macro should be used by passes to emit debug
 /// information.  In the '-debug' option is specified on the commandline, and if
 /// this is a debug build, then the code specified as the option to the macro
@@ -67,6 +73,7 @@
 #else
 #define isCurrentDebugType(X) (false)
 #define setCurrentDebugType(X)
+#define setCurrentDebugTypes(X, N)
 #define DEBUG_WITH_TYPE(TYPE, X) do { } while (false)
 #endif
 
Index: lib/Support/Debug.cpp
===================================================================
--- lib/Support/Debug.cpp
+++ lib/Support/Debug.cpp
@@ -63,10 +63,14 @@
 /// debug output to be produced.
 ///
 void setCurrentDebugType(const char *Type) {
-  CurrentDebugType->clear();
-  CurrentDebugType->push_back(Type);
+  setCurrentDebugTypes(&Type, 1);
 }
 
+void setCurrentDebugTypes(const char **Types, size_t Count) {
+  CurrentDebugType->clear();
+  for (size_t T = 0; T < Count; ++T)
+    CurrentDebugType->push_back(Types[T]);
+}
 } // namespace llvm
 
 // All Debug.h functionality is a no-op in NDEBUG mode.