Instead of passing in an unsigned value for the optimization level, use an enum,
which better identifies what the optimization is doing. And is more flexible for
future uses.

llvm-svn: 70440
diff --git a/llvm/lib/ExecutionEngine/ExecutionEngine.cpp b/llvm/lib/ExecutionEngine/ExecutionEngine.cpp
index e64af91..9cd03da 100644
--- a/llvm/lib/ExecutionEngine/ExecutionEngine.cpp
+++ b/llvm/lib/ExecutionEngine/ExecutionEngine.cpp
@@ -383,7 +383,7 @@
 ExecutionEngine *ExecutionEngine::create(ModuleProvider *MP,
                                          bool ForceInterpreter,
                                          std::string *ErrorStr,
-                                         unsigned OptLevel) {
+                                         CodeGenOpt::Level OptLevel) {
   ExecutionEngine *EE = 0;
 
   // Make sure we can resolve symbols in the program as well. The zero arg