[stubs] A new approach to TF stubs

test/mjsunit/get-caller-js-function.js

-// 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.
-
-// Flags: --allow-natives-syntax --turbo-filter=* --nostress-opt
-
-// Test that for fully optimized but non inlined code, GetCallerJSFunction walks
-// up a single stack frame to get the calling function. Full optimization elides
-// the check in the runtime version of the intrinsic that would throw since the
-// caller isn't a stub. It's a bit of a hack, but allows minimal testing of the
-// intrinsic without writing a full-blown cctest.
-(function() {
-  var a = function() {
-    return %_GetCallerJSFunction();
-  };
-  var b = function() {
-    return a();
-  };
-  %OptimizeFunctionOnNextCall(a);
-  assertEquals(b, b());
-}());