rust/library
Mara Bos 152f425dcb
Rollup merge of #80201 - saethlin:bufreader-read-exact, r=KodrAus
Add benchmark and fast path for BufReader::read_exact

At work, we have a wrapper type that implements this optimization. It would be nice if the standard library were faster.

Before:
```
test io::buffered::tests::bench_buffered_reader_small_reads       ... bench:       7,670 ns/iter (+/- 45)
```
After:
```
test io::buffered::tests::bench_buffered_reader_small_reads       ... bench:       4,457 ns/iter (+/- 41)
```
2021-01-17 12:24:42 +00:00
..
2020-12-21 00:00:00 +00:00
2021-01-07 16:16:36 +09:00