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 // Tests that we can use debug scopes with Ion frames.

 //

 // Unfortunately these tests are brittle. They depend on opaque JIT heuristics

 // kicking in.

 load(libdir + "jitopts.js");

 if (!jitTogglesMatch(Opts_Ion2NoParallelCompilation))

   quit(0);

 withJitOptions(Opts_Ion2NoParallelCompilation, function () {

   var g = newGlobal();

   var dbg = new Debugger;

   // Note that this *depends* on CCW scripted functions being opaque to Ion

   // optimization and not deoptimizing the frames below the call to toggle.

   g.toggle = function toggle(d) {

     if (d) {

       dbg.addDebuggee(g);

       var frame = dbg.getNewestFrame();

       assertEq(frame.implementation, "ion");

       // g is heavyweight but its call object is optimized out, because its

       // arguments and locals are unaliased.

       //

       // Calling frame.environment here should make a fake debug scope that

       // gets things directly from the frame. Calling frame.arguments doesn't

       // go through the scope object and reads directly off the frame. Assert

       // that the two are equal.

       assertEq(frame.environment.getVariable("x"), frame.arguments[1]);

     }

   };

   g.eval("" + function f(d, x) { g(d, x); });

   g.eval("" + function g(d, x) {

     for (var i = 0; i < 200; i++);

     function inner() { i = 42; };

     toggle(d);

     // Use x so it doesn't get optimized out.

     x++;

   });

   g.eval("(" + function test() {

     for (i = 0; i < 5; i++)

       f(false, 42);

     f(true, 42);

   } + ")();");

 });