[jdk25u-dev] Integrated: 8370405: C2: mismatched store from MergeStores wrongly scalarized in allocation elimination

[Aleksey Shipilev]

On Wed, 26 Nov 2025 10:15:17 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
>  - [x] Linux x86_64 server fastdebug, `all`

This pull request has now been integrated.

Changeset: d1b5b9a5
Author:    Aleksey Shipilev <shade at openjdk.org>
URL:       https://git.openjdk.org/jdk25u-dev/commit/d1b5b9a592520096139bbc2906132ac16434f9ca
Stats:     375 lines in 5 files changed: 375 ins; 0 del; 0 mod

8370405: C2: mismatched store from MergeStores wrongly scalarized in allocation elimination

Backport-of: 09a047f00c88d14505c42a966dedbc87b9be5bdf

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PR: https://git.openjdk.org/jdk25u-dev/pull/10