author Dustin J. Mitchell <>
Wed, 07 Sep 2016 00:10:51 +0000
changeset 354971 1627fd341fc154d4fb771366676b7101204362df
parent 214333 91d7659bb35145e10ff737753688e0972c1a79b5
child 505383 6f3709b3878117466168c40affa7bca0b60cf75b
permissions -rw-r--r--
Bug 1286075: allow optimization of tasks whose dependencies have not been optimized; r=armenzg MikeLing initially did this in bug 1287018. The intent of this conditional was to make optimization faster by not even checking most tasks, based on the assumption that if the prerequisite to a task has changed (for example, a docker image or a build), then naturally we will want to execute that task. However, as we have developed actual optimization methods, this has proven not to be the case: we might want to optimize a test out if its inputs have not changed, even if a new installer has been built. Similarly, SETA may optimize tasks out even if their inputs have changed. MozReview-Commit-ID: LgHET3Z84GB

/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim: set ts=8 sts=2 et sw=2 tw=80: */
/* 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 */

/* Implementations of hash functions. */

#include "mozilla/HashFunctions.h"
#include "mozilla/Types.h"

#include <string.h>

namespace mozilla {

HashBytes(const void* aBytes, size_t aLength)
  uint32_t hash = 0;
  const char* b = reinterpret_cast<const char*>(aBytes);

  /* Walk word by word. */
  size_t i = 0;
  for (; i < aLength - (aLength % sizeof(size_t)); i += sizeof(size_t)) {
    /* Do an explicitly unaligned load of the data. */
    size_t data;
    memcpy(&data, b + i, sizeof(size_t));

    hash = AddToHash(hash, data, sizeof(data));

  /* Get the remaining bytes. */
  for (; i < aLength; i++) {
    hash = AddToHash(hash, b[i]);
  return hash;

} /* namespace mozilla */