hash/maphash: add Bytes and String

For very small inputs, h.Reset+h.Write+h.Sum64 is fundamentally
slower than a single operation, by about a factor of two, because
Write must copy the data into h's buffer, just in case there is another
Write before the Sum64.

A single function doing the whole sequence knows there is no extra
write that will happen, so it doesn't need the buffer, so it avoids the copy.

Fixes #42710.

Change-Id: Icc79c68ccb10827f6640071d026df86b4940fcc1
Reviewed-on: https://go-review.googlesource.com/c/go/+/392494
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Trust: Russ Cox <rsc@golang.org>
Run-TryBot: Russ Cox <rsc@golang.org>
TryBot-Result: Gopher Robot <gobot@golang.org>

0 files changed, 0 insertions, 0 deletions