gecko/tools/profiler/tests/head_profiler.js

32 lines
1.2 KiB
JavaScript

/* 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();
}