RFR: 8358592: Assert in Assembler::ptest due to missing SSE42 support [v6]

[Guanqiang Han]

On Tue, 15 Jul 2025 16:51:57 GMT, Vladimir Kozlov <kvn at openjdk.org> wrote:

>> Guanqiang Han has updated the pull request with a new target base due to a merge or a rebase. The incremental webrev excludes the unrelated changes brought in by the merge/rebase. The pull request contains nine additional commits since the last revision:
>> 
>>  - move UseSSE42Intrinsics check outside of the CPU-specific sections
>>  - Merge remote-tracking branch 'upstream/master' into 8358592
>>  - Update full name
>>  - Merge remote-tracking branch 'upstream/master' into 8358592
>>  - update regression test
>>  - Update Test8358592.java
>>    
>>    run on x86_64
>>  - add regression test for JDK-8358592
>>  - Merge remote-tracking branch 'upstream/master' into 8358592
>>  - 8358592: Assert in Assembler::ptest due to missing SSE42 support
>>    
>>    Setting "-XX:UseSSE=1" in command line prevents the code from entering the block which causes UseSSE42Intrinsics to not be correctly set.
>
> src/hotspot/cpu/x86/vm_version_x86.cpp line 1637:
> 
>> 1635:         }
>> 1636:       } else {
>> 1637:         if (UseSSE42Intrinsics && !FLAG_IS_DEFAULT(UseAESIntrinsics)) {
> 
> Ha, there was bug in all these checks: checking `UseAESIntrinsics` instead of `UseSSE42Intrinsics`!
> 
> Thank you for fixing it in your changes

@vnkozlov 
You're welcome! I noticed the inconsistency while reviewing the existing logic, so I thought it’d be good to fix it as part of this cleanup.

Glad it helps!

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PR Review Comment: https://git.openjdk.org/jdk/pull/26151#discussion_r2208844858