On Fri, 27 Jun 2025 01:04:32 GMT, Shaojin Wen <s...@openjdk.org> wrote:
>> In BufferedReader.readLine and other similar scenarios, we need to use
>> StringBuilder.append(char[]) to build the string.
>>
>> For these scenarios, we can Unsafe.copyMemory instead of the character copy
>> of the char-by-char loop to improve the speed.
>>
>> @RogerRiggs completed the optimization when the encoder is LATIN1 in PR
>> #24967. This PR continues to complete the optimization when the encoder is
>> UTF16.
>
> Shaojin Wen has updated the pull request incrementally with one additional
> commit since the last revision:
>
> Update src/java.base/share/classes/java/lang/StringUTF16.java
>
> Co-authored-by: Chen Liang <li...@openjdk.org>
src/java.base/share/classes/java/lang/StringUTF16.java line 1487:
> 1485: Unsafe.getUnsafe().copyMemory(
> 1486: ca,
> 1487: Unsafe.ARRAY_CHAR_BASE_OFFSET + ((long) off << 1),
Suggestion:
Unsafe.ARRAY_CHAR_BASE_OFFSET + (long) off *
Unsafe.ARRAY_CHAR_INDEX_SCALE,
src/java.base/share/classes/java/lang/StringUTF16.java line 1489:
> 1487: Unsafe.ARRAY_CHAR_BASE_OFFSET + ((long) off << 1),
> 1488: val,
> 1489: Unsafe.ARRAY_BYTE_BASE_OFFSET + ((long) index << 1),
Suggestion:
Unsafe.ARRAY_BYTE_BASE_OFFSET + ((long) index << 1) *
Unsafe.ARRAY_BYTE_INDEX_SCALE,
-------------
PR Review Comment: https://git.openjdk.org/jdk/pull/24773#discussion_r2228828535
PR Review Comment: https://git.openjdk.org/jdk/pull/24773#discussion_r2228829451
