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 // Check that the EnterJIT frame, added by the JIT trampoline and

 // usable by a native unwinder to resume unwinding after encountering

 // JIT code, is pushed as expected.

 function run_test() {

     let p = Cc["@mozilla.org/tools/profiler;1"];

     // Just skip the test if the profiler component isn't present.

     if (!p)

 	return;

     p = p.getService(Ci.nsIProfiler);

     if (!p)

 	return;

     // This test assumes that it's starting on an empty SPS stack.

     // (Note that the other profiler tests also assume the profiler

     // isn't already started.)

     do_check_true(!p.IsActive());

     const ms = 5;

     p.StartProfiler(100, ms, ["js"], 1);

     let profile = (function arbitrary_name(){

 	// A frame for |arbitrary_name| has been pushed.

 	let then = Date.now();

 	do {

 	    let n = 10000;

 	    while (--n); // OSR happens here

 	    // Spin until we're sure we have a sample.

 	} while (Date.now() - then < ms * 2.5);

 	return p.getProfileData().threads[0].samples;

     })();

     do_check_neq(profile.length, 0);

     let stack = profile[profile.length - 1].frames.map(f => f.location);

     stack = stack.slice(stack.indexOf("js::RunScript") + 1);

     do_print(stack);

     // This test needs to not break on platforms and configurations

     // where IonMonkey isn't available / enabled.

     if (stack.length < 2 || stack[1] != "EnterJIT") {

 	do_print("No JIT?");

 	// Try to check what we can....

 	do_check_eq(Math.min(stack.length, 1), 1);

 	let thisInterp = stack[0];

 	do_check_eq(thisInterp.split(" ")[0], "arbitrary_name");

 	if (stack.length >= 2) {

 	    let nextFrame = stack[1];

 	    do_check_neq(nextFrame.split(" ")[0], "arbitrary_name");

 	}

     } else {

 	do_check_eq(Math.min(stack.length, 3), 3);

 	let thisInterp = stack[0];

 	let enterJit = stack[1];

 	let thisBC = stack[2];

 	do_check_eq(thisInterp.split(" ")[0], "arbitrary_name");

 	do_check_eq(enterJit, "EnterJIT");

 	do_check_eq(thisBC.split(" ")[0], "arbitrary_name");

     }

     p.StopProfiler();

 }