import FIREFOX_52_6_0esr_RELEASE from mozilla-esr52 hg repo

tools/profiler/tests/head_profiler.js

@@ -0,0 +1,31 @@
+/* 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/. */
+
+const Cc = Components.classes;
+const Ci = Components.interfaces;
+const Cu = Components.utils;
+
+function getInflatedStackLocations(thread, sample) {
+  let stackTable = thread.stackTable;
+  let frameTable = thread.frameTable;
+  let stringTable = thread.stringTable;
+  let SAMPLE_STACK_SLOT = thread.samples.schema.stack;
+  let STACK_PREFIX_SLOT = stackTable.schema.prefix;
+  let STACK_FRAME_SLOT = stackTable.schema.frame;
+  let FRAME_LOCATION_SLOT = frameTable.schema.location;
+
+  // Build the stack from the raw data and accumulate the locations in
+  // an array.
+  let stackIndex = sample[SAMPLE_STACK_SLOT];
+  let locations = [];
+  while (stackIndex !== null) {
+    let stackEntry = stackTable.data[stackIndex];
+    let frame = frameTable.data[stackEntry[STACK_FRAME_SLOT]];
+    locations.push(stringTable[frame[FRAME_LOCATION_SLOT]]);
+    stackIndex = stackEntry[STACK_PREFIX_SLOT];
+  }
+
+  // The profiler tree is inverted, so reverse the array.
+  return locations.reverse();
+}