The Tor Browser / file revision

 // Eval-in-frame of optimized frames to break out of an infinite loop.

 load(libdir + "jitopts.js");

 if (!jitTogglesMatch(Opts_IonEagerNoParallelCompilation))

   quit(0);

 withJitOptions(Opts_IonEagerNoParallelCompilation, function () {

   var g = newGlobal();

   var dbg = new Debugger;

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

   g.eval("" + function g(d) { h(d); });

   g.eval("" + function h(d) {

     var i = 0;

     while (d)

       interruptIf(d && i++ == 4000);

   });

   setInterruptCallback(function () {

     dbg.addDebuggee(g);

     var frame = dbg.getNewestFrame();

     if (frame.callee.name != "h" || frame.implementation != "ion")

       return true;

     frame.eval("d = false;");

     return true;

   });

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

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

       f(false);

     f(true);

   } + ")();");

 });