Add named timer groups for the different stages of register allocation.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@121604 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/CodeGen/RegAllocBase.h b/lib/CodeGen/RegAllocBase.h
index 7d13327..438a7d1 100644
--- a/lib/CodeGen/RegAllocBase.h
+++ b/lib/CodeGen/RegAllocBase.h
@@ -153,6 +153,9 @@
   void verify();
 #endif
 
+  // Use this group name for NamedRegionTimer.
+  static const char *TimerGroupName;
+
 private:
   void seedLiveVirtRegs(std::priority_queue<std::pair<float, unsigned> >&);