I don't know that it exists for any other architectures.

Update #18616

Change-Id: Idfe5dee251764d32787915889ec0be4bebc5be24
Reviewed-on: https://go-review.googlesource.com/38323
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Robert Griesemer <gri@golang.org>