1 files changed, 46 insertions, 0 deletions
diff --git a/js/src/devtools/gc-ubench/benchmarks/pairCyclicWeakMap.js b/js/src/devtools/gc-ubench/benchmarks/pairCyclicWeakMap.js
new file mode 100644
index 0000000000..ac43325b6f
--- /dev/null
+++ b/js/src/devtools/gc-ubench/benchmarks/pairCyclicWeakMap.js
@@ -0,0 +1,46 @@
+/* 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/. */
+
+tests.set(
+  "pairCyclicWeakMap",
+  (function() {
+    var garbage = [];
+    var garbageIndex = 0;
+    return {
+      description: "wm1[k1] = k2; wm2[k2] = k3; wm1[k3] = k4; wm2[k4] = ...",
+
+      defaultGarbagePerFrame: "10K",
+      defaultGarbagePiles: "1K",
+
+      load: N => {
+        garbage = new Array(N);
+      },
+
+      unload: () => {
+        garbage = [];
+        garbageIndex = 0;
+      },
+
+      makeGarbage: M => {
+        var wm1 = new WeakMap();
+        var wm2 = new WeakMap();
+        var initialKey = {};
+        var key = initialKey;
+        var value = {};
+        for (var i = 0; i < M / 2; i++) {
+          wm1.set(key, value);
+          key = value;
+          value = {};
+          wm2.set(key, value);
+          key = value;
+          value = {};
+        }
+        garbage[garbageIndex++] = [initialKey, wm1, wm2];
+        if (garbageIndex == garbage.length) {
+          garbageIndex = 0;
+        }
+      },
+    };
+  })()
+);