Implement thin-lock fast path for compiler-llvm.

Change-Id: I09d6a0dba4df7cbeb0c0e3f432ab3b09fce0846d
diff --git a/src/compiler_llvm/runtime_support_builder.h b/src/compiler_llvm/runtime_support_builder.h
index 89cf30a..7b54c69 100644
--- a/src/compiler_llvm/runtime_support_builder.h
+++ b/src/compiler_llvm/runtime_support_builder.h
@@ -60,6 +60,10 @@
   virtual llvm::Value* EmitIsExceptionPending();
   virtual void EmitTestSuspend();
 
+  /* Monitor */
+  virtual void EmitLockObject(llvm::Value* object);
+  virtual void EmitUnlockObject(llvm::Value* object);
+
   llvm::Function* GetRuntimeSupportFunction(runtime_support::RuntimeId id) {
     if (id >= 0 && id < runtime_support::MAX_ID) {
       return runtime_support_func_decls_[id];