[jdk25u] RFR: 8370405: C2: mismatched store from MergeStores wrongly scalarized in allocation elimination [v2]

[Aleksey Shipilev]

On Thu, 20 Nov 2025 16:16:51 GMT, Aleksey Shipilev <shade at openjdk.org> wrote:

>> Fixes JDK 21 -> JDK 25 regression in C2 that can lead to miscompilation. There is a regression test that captures the failure.
>> 
>> Additional testing:
>>  - [x] Linux x86_64 server fastdebug, new regression test fails without the fix, passes with it
>>  - [ ] Linux x86_64 server fastdebug, `all`
>
> Aleksey Shipilev has updated the pull request incrementally with one additional commit since the last revision:
> 
>   Backport 59d23095789bbb6d4e466bcbeb82089b17d78eae

Closing in favor of https://github.com/openjdk/jdk25u-dev/pull/10.

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PR Comment: https://git.openjdk.org/jdk25u/pull/382#issuecomment-3580603036