time/format: avoid growslice in time.String()/time.GoString()
Pre-allocate the slice of buf with enough capacity
to avoid growslice calls.
benchmark old ns/op new ns/op delta
BenchmarkTimeString-4 493 409 -17.12%
BenchmarkTimeGoString-4 309 182 -41.30%
benchmark old allocs new allocs delta
BenchmarkTimeString-4 5 3 -40.00%
BenchmarkTimeGoString-4 4 1 -75.00%
benchmark old bytes new bytes delta
BenchmarkTimeString-4 152 128 -15.79%
BenchmarkTimeGoString-4 248 80 -67.74%
Change-Id: I64eabe2ab0b3d4a846453c2e8e548a831d720b8c
Reviewed-on: https://go-review.googlesource.com/c/go/+/343971
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Trust: Alexander Rakoczy <alex@golang.org>