We really need 3 mix steps between the data being hashed and the output.
One mix can only spread a 1 bit change to 32 bits. The second mix
can spread to all 128 bits, but the spread is not complete. A third mix
spreads out ~evenly to all 128 bits.
The amd64 version has 3 mix steps.
Fixes #59643
Change-Id: I54ad8686ca42bcffb6d0ec3779d27af682cc96e9
Reviewed-on: https://go-review.googlesource.com/c/go/+/486616
Run-TryBot: Keith Randall <khr@golang.org> Reviewed-by: Keith Randall <khr@google.com> Reviewed-by: Cherry Mui <cherryyz@google.com>
TryBot-Result: Gopher Robot <gobot@golang.org>