1 files changed, 158 insertions, 0 deletions
diff --git a/tools/profiler/tests/xpcshell/test_feature_nativeallocations.js b/tools/profiler/tests/xpcshell/test_feature_nativeallocations.js
new file mode 100644
index 0000000000..64398d7ef9
--- /dev/null
+++ b/tools/profiler/tests/xpcshell/test_feature_nativeallocations.js
@@ -0,0 +1,158 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+add_task(async () => {
+  if (!Services.profiler.GetFeatures().includes("nativeallocations")) {
+    Assert.ok(
+      true,
+      "Native allocations are not supported by this build, " +
+        "skip run the rest of the test."
+    );
+    return;
+  }
+
+  Assert.ok(
+    !Services.profiler.IsActive(),
+    "The profiler is not currently active"
+  );
+
+  info(
+    "Test that the profiler can install memory hooks and collect native allocation " +
+      "information in the marker payloads."
+  );
+  {
+    info("Start the profiler.");
+    await startProfiler({
+      // Only instrument the main thread.
+      threads: ["GeckoMain"],
+      features: ["js", "nativeallocations"],
+    });
+
+    info(
+      "Do some JS work for a little bit. This will increase the amount of allocations " +
+        "that take place."
+    );
+    doWork();
+
+    info("Get the profile data and analyze it.");
+    const profile = await waitSamplingAndStopAndGetProfile();
+
+    const {
+      allocationPayloads,
+      unmatchedAllocations,
+      logAllocationsAndDeallocations,
+    } = getAllocationInformation(profile);
+
+    Assert.greater(
+      allocationPayloads.length,
+      0,
+      "Native allocation payloads were recorded for the parent process' main thread when " +
+        "the Native Allocation feature was turned on."
+    );
+
+    if (unmatchedAllocations.length !== 0) {
+      info(
+        "There were unmatched allocations. Log all of the allocations and " +
+          "deallocations in order to aid debugging."
+      );
+      logAllocationsAndDeallocations();
+      ok(
+        false,
+        "Found a deallocation that did not have a matching allocation site. " +
+          "This could happen if balanced allocations is broken, or if the the " +
+          "buffer size of this test was too small, and some markers ended up " +
+          "rolling off."
+      );
+    }
+
+    ok(true, "All deallocation sites had matching allocations.");
+  }
+
+  info("Restart the profiler, to ensure that we get no more allocations.");
+  {
+    await startProfiler({ features: ["js"] });
+    info("Do some work again.");
+    doWork();
+    info("Wait for the periodic sampling.");
+    const profile = await waitSamplingAndStopAndGetProfile();
+    const allocationPayloads = getPayloadsOfType(
+      profile.threads[0],
+      "Native allocation"
+    );
+
+    Assert.equal(
+      allocationPayloads.length,
+      0,
+      "No native allocations were collected when the feature was disabled."
+    );
+  }
+});
+
+function doWork() {
+  this.n = 0;
+  for (let i = 0; i < 1e5; i++) {
+    this.n += Math.random();
+  }
+}
+
+/**
+ * Extract the allocation payloads, and find the unmatched allocations.
+ */
+function getAllocationInformation(profile) {
+  // Get all of the allocation payloads.
+  const allocationPayloads = getPayloadsOfType(
+    profile.threads[0],
+    "Native allocation"
+  );
+
+  // Decide what is an allocation and deallocation.
+  const allocations = allocationPayloads.filter(
+    payload => ensureIsNumber(payload.size) >= 0
+  );
+  const deallocations = allocationPayloads.filter(
+    payload => ensureIsNumber(payload.size) < 0
+  );
+
+  // Now determine the unmatched allocations by building a set
+  const allocationSites = new Set(
+    allocations.map(({ memoryAddress }) => memoryAddress)
+  );
+
+  const unmatchedAllocations = deallocations.filter(
+    ({ memoryAddress }) => !allocationSites.has(memoryAddress)
+  );
+
+  // Provide a helper to log out the allocations and deallocations on failure.
+  function logAllocationsAndDeallocations() {
+    for (const { memoryAddress } of allocations) {
+      console.log("Allocations", formatHex(memoryAddress));
+      allocationSites.add(memoryAddress);
+    }
+
+    for (const { memoryAddress } of deallocations) {
+      console.log("Deallocations", formatHex(memoryAddress));
+    }
+
+    for (const { memoryAddress } of unmatchedAllocations) {
+      console.log("Deallocation with no allocation", formatHex(memoryAddress));
+    }
+  }
+
+  return {
+    allocationPayloads,
+    unmatchedAllocations,
+    logAllocationsAndDeallocations,
+  };
+}
+
+function ensureIsNumber(value) {
+  if (typeof value !== "number") {
+    throw new Error(`Expected a number: ${value}`);
+  }
+  return value;
+}
+
+function formatHex(number) {
+  return `0x${number.toString(16)}`;
+}