RFR: 8320448: Accelerate IndexOf using AVX2 [v18]

[Scott Gibbons]

On Wed, 15 May 2024 19:41:58 GMT, Volodymyr Paprotski <duke at openjdk.org> wrote:

>> Scott Gibbons has updated the pull request with a new target base due to a merge or a rebase. The pull request now contains 50 commits:
>> 
>>  - Merge remote-tracking branch 'origin/master' into indexof
>>  - Move arrays_equals back to c2_MacroAssembler
>>  - Merge branch 'openjdk:master' into indexof
>>  - Remove infinite loop (used for debugging)
>>  - Merge branch 'openjdk:master' into indexof
>>  - Cleaned up, ready for review
>>  - Pre-cleanup code
>>  - Add JMH. Add 16-byte compares to arrays_equals
>>  - Better method for mask creation
>>  - Merge branch 'openjdk:master' into indexof
>>  - ... and 40 more: https://git.openjdk.org/jdk/compare/b20fa7b4...f52d281d
>
> test/jdk/java/lang/StringBuffer/IndexOf.java line 81:
> 
>> 79:   String shs = (new String((hs_charset == StandardCharsets.UTF_16) ? haystack_16 : haystack)).substring(0, haystackSize);
>> 80: 
>> 81:   shs = "$&),,18+-!'8)+";
> 
> Should really keep the original test unmodified and add new tests as needed

The test functionality was not changed.  I just added printing of information when a failure occurs.

-------------

PR Review Comment: https://git.openjdk.org/jdk/pull/16753#discussion_r1613914184