tools/profiler/tests/xpcshell/test_enterjit_osr.js

   1 // Check that the EnterJIT frame, added by the JIT trampoline and
   2 // usable by a native unwinder to resume unwinding after encountering
   3 // JIT code, is pushed as expected.
   4 function run_test() {
   5   // This test assumes that it's starting on an empty profiler stack.
   6   // (Note that the other profiler tests also assume the profiler
   7   // isn't already started.)
   8   Assert.ok(!Services.profiler.IsActive());
   9
  10   const ms = 5;
  11   Services.profiler.StartProfiler(10000, ms, ["js"]);
  12
  13   function has_arbitrary_name_in_stack() {
  14     // A frame for |arbitrary_name| has been pushed.  Do a sequence of
  15     // increasingly long spins until we get a sample.
  16     var delayMS = 5;
  17     while (1) {
  18       info("loop: ms = " + delayMS);
  19       const then = Date.now();
  20       do {
  21         let n = 10000;
  22         // eslint-disable-next-line no-empty
  23         while (--n) {} // OSR happens here
  24         // Spin in the hope of getting a sample.
  25       } while (Date.now() - then < delayMS);
  26       let profile = Services.profiler.getProfileData().threads[0];
  27
  28       // Go through all of the stacks, and search for this function name.
  29       for (const sample of profile.samples.data) {
  30         const stack = getInflatedStackLocations(profile, sample);
  31         info(`The following stack was found: ${stack}`);
  32         for (var i = 0; i < stack.length; i++) {
  33           if (stack[i].match(/arbitrary_name/)) {
  34             // This JS sample was correctly found.
  35             return true;
  36           }
  37         }
  38       }
  39
  40       // Continue running this function with an increasingly long delay.
  41       delayMS *= 2;
  42       if (delayMS > 30000) {
  43         return false;
  44       }
  45     }
  46   }
  47   Assert.ok(
  48     has_arbitrary_name_in_stack(),
  49     "A JS frame was found before the test timeout."
  50   );
  51   Services.profiler.StopProfiler();
  52 }