port d412cfa2 (r35596)

  original commit message:
  Reland of (https://codereview.chromium.org/1891033002)

  This is a much cleaner solution, which won't require nearly as much
  architecture-specific code. Thanks bmeurer@!

BUG=

Review URL: https://codereview.chromium.org/1897143003

Cr-Commit-Position: refs/heads/master@{#35603}