bytes,slices,strings: optimize Repeat a bit
Like slices.Repeat, use math/bits.Mul to detect overflow in order to
avoid a divide which is slow.
While here, also use builtin min/max to simplify code.
Change-Id: I4a6d8cd5df97fa75f4e324d4be1405ce53c03d31
GitHub-Last-Rev:
54ba5c7126b1d4a301e95d664b5f6deee6d579d9
GitHub-Pull-Request: golang/go#68704
Reviewed-on: https://go-review.googlesource.com/c/go/+/602475
Auto-Submit: Ian Lance Taylor <iant@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Reviewed-by: Ian Lance Taylor <iant@google.com>
Reviewed-by: Michael Knyszek <mknyszek@google.com>