diff -r 000000000000 -r 6474c204b198 js/src/devtools/gc/tests/loops.js
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/js/src/devtools/gc/tests/loops.js	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,55 @@
+//Measure plain GC.
+
+var t = [];
+var N = 500000
+
+for(var i = 0; i < N; i++)
+    t[i] = {};
+
+gc()
+
+t = [];
+
+gc();
+
+for(var i = 0; i < N; i++)
+    t[i] = ({});
+
+gc();
+
+t = [];
+
+gc();
+
+
+for(var i = 0; i < N; i++)
+    t[i] = "asdf";
+    
+gc();
+
+t = [];
+
+gc();
+
+
+for(var i = 0; i < N; i++)
+    t[i] = 1.12345;
+    
+gc();
+
+t=[];
+
+gc();
+
+for(var i = 0; i < N; i++) {
+    t[i] = ({});
+    if (i != 0)
+        t[i].a = t[i-1];
+}
+    
+gc();
+
+t = [];
+
+gc();
+