Accelerate isel dispatch for tables that start with a top-level

OPC_SwitchOpcode to use a table lookup instead of having to go
through the interpreter for this.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@97469 91177308-0d34-0410-b5e6-96231b3b80d8

include/llvm/CodeGen/SelectionDAGISel.h

@@ -245,6 +245,10 @@ private:
   /// one preferred by the target.
   ///
   ScheduleDAGSDNodes *CreateScheduler();
+  
+  /// OpcodeOffset - This is a cache used to dispatch efficiently into isel
+  /// state machines that start with a OPC_SwitchOpcode node.
+  std::vector<unsigned> OpcodeOffset;
 };
 
 }