On Sat, 29 Jun 2024 16:16:51 GMT, David Schlosnagle <d...@openjdk.org> wrote:
>> Shaojin Wen has updated the pull request incrementally with one additional
>> commit since the last revision:
>>
>> rename `digit` to `width`
>
> src/java.base/share/classes/java/lang/StringFormat.java line 82:
>
>> 80: conv = format.charAt(off + 2);
>> 81: }
>> 82: }
>
> is it worth handling `width > 9`?
>
> Suggestion:
>
> for (int i = 2; conv >= '1' && conv <= '9' && off + i < max; i++) {
> width = (width * 10) + (conv - '0');
> if (off + i < max) {
> conv = format.charAt(off + i);
> }
> }
a quick local benchmark on 2021 MacBook M1 Pro before/after motivating this:
@Benchmark
public String wideStringIntFormat() {
return "%123s %42d".formatted(s, i);
}
#### Before:
Benchmark Mode Cnt Score Error Units
StringFormat.wideStringIntFormat avgt 15 377.603 ± 85.742 ns/op
#### After:
Benchmark Mode Cnt Score Error Units
StringFormat.wideStringIntFormat avgt 15 54.104 ± 0.079 ns/op
-------------
PR Review Comment: https://git.openjdk.org/jdk/pull/19956#discussion_r1659916636
