Forward decls.

llvm-svn: 72114
diff --git a/llvm/lib/CodeGen/Spiller.h b/llvm/lib/CodeGen/Spiller.h
index e838508..730419b 100644
--- a/llvm/lib/CodeGen/Spiller.h
+++ b/llvm/lib/CodeGen/Spiller.h
@@ -14,6 +14,9 @@
 
 namespace llvm {
   struct LiveInterval;
+  class LiveIntervals;
+  class MachineFunction;
+  class VirtRegMap;
 
   /// Spiller interface.
   ///