[interpreter] Adds interpreter cctests.

test/cctest/interpreter/test-interpreter.cc

+// Copyright 2015 the V8 project authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "src/v8.h"
+
+#include "src/execution.h"
+#include "src/handles.h"
+#include "src/interpreter/bytecode-array-builder.h"
+#include "src/interpreter/interpreter.h"
+#include "test/cctest/cctest.h"
+
+namespace v8 {
+namespace internal {
+
+class InterpreterTester {
+ public:
+  InterpreterTester(Isolate* isolate, Handle<BytecodeArray> bytecode)
+      : isolate_(isolate), function_(GetBytecodeFunction(isolate, bytecode)) {
+    i::FLAG_ignition = true;
+    Handle<FixedArray> empty_array = isolate->factory()->empty_fixed_array();
+    Handle<FixedArray> interpreter_table =
+        isolate->factory()->interpreter_table();
+    if (interpreter_table.is_identical_to(empty_array)) {
+      // Ensure handler table is generated.
+      isolate->interpreter()->Initialize(true);
+    }
+  }
+  virtual ~InterpreterTester() {}
+
+  MaybeHandle<Object> Call() {

[titzer, 2015/07/31 12:09:12]

Can we factor the Call() out of the tester?

This is one of the design mistakes I think we made with the way the other
integration tests work. The tester should produce a Callable thingy, which has a
Call() or an operator()

[rmcilroy, 2015/07/31 17:52:59]

Done.

+    Handle<Object> args[] = {};
+    return Execution::Call(isolate_, function_,
+                           isolate_->factory()->undefined_value(), 0, args,
+                           false);
+  }
+
+ private:
+  Isolate* isolate_;
+  Handle<JSFunction> function_;
+
+  static Handle<JSFunction> GetBytecodeFunction(
+      Isolate* isolate, Handle<BytecodeArray> bytecode_array) {
+    Handle<JSFunction> function = v8::Utils::OpenHandle(
+        *v8::Handle<v8::Function>::Cast(CompileRun("(function(){})")));
+    function->ReplaceCode(*isolate->builtins()->InterpreterEntryTrampoline());
+    function->shared()->set_function_data(*bytecode_array);
+    return function;
+  }
+};
+
+}  // namespace internal
+}  // namespace v8
+
+using namespace v8::internal;
+using namespace v8::internal::interpreter;
+
+TEST(TestInterpreterReturn) {
+  InitializedHandleScope handles;
+  Handle<Object> undefined_value =
+      handles.main_isolate()->factory()->undefined_value();
+
+  BytecodeArrayBuilder builder(handles.main_isolate());
+  // TODO(rmcilroy) set to 0 once BytecodeArray update to allow zero size
+  // register file.
+  builder.set_locals_count(1);
+  builder.Return();
+  Handle<BytecodeArray> bytecode_array = builder.ToBytecodeArray();
+
+  InterpreterTester tester(handles.main_isolate(), bytecode_array);
+  Handle<Object> return_val = tester.Call().ToHandleChecked();
+  CHECK(return_val.is_identical_to(undefined_value));
+}