CodeStubAssembler can generate code for builtins

test/cctest/compiler/function-tester.h

Index: test/cctest/compiler/function-tester.h
diff --git a/test/cctest/compiler/function-tester.h b/test/cctest/compiler/function-tester.h
index b48b4d298adce13fbac90732374b13dd19ed8c57..77627086d74e95f4662c7334c6eddf034a83883d 100644
--- a/test/cctest/compiler/function-tester.h
+++ b/test/cctest/compiler/function-tester.h
@@ -42,6 +42,14 @@ class FunctionTester : public InitializedHandleScope {
     CompileGraph(graph);
   }
 
+  FunctionTester(int param_count, Handle<Code> code)
+      : isolate(main_isolate()),
+        function(NewFunction(BuildFunction(param_count).c_str())),
+        flags_(0) {
+    Compile(function);
+    function->ReplaceCode(*code);
+  }
+
   FunctionTester(const CallInterfaceDescriptor& descriptor, Handle<Code> code)
       : isolate(main_isolate()),
         function(
@@ -64,6 +72,12 @@ class FunctionTester : public InitializedHandleScope {
     return Execution::Call(isolate, function, undefined(), 2, args);
   }
 
+  MaybeHandle<Object> Call(Handle<Object> a, Handle<Object> b,
+                           Handle<Object> c) {
+    Handle<Object> args[] = {a, b, c};
+    return Execution::Call(isolate, function, undefined(), 3, args);
+  }
+
   MaybeHandle<Object> Call(Handle<Object> a, Handle<Object> b, Handle<Object> c,
                            Handle<Object> d) {
     Handle<Object> args[] = {a, b, c, d};