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

BUG=v8:4614
LOG=y
R=bmeurer@chromium.org,jarin@chromium.org

Review URL: https://codereview.chromium.org/1891033002

Cr-Commit-Position: refs/heads/master@{#35547}