[lworld] RFR: 8376702: [lworld] MemNode::optimize_simple_memory_chain asserts with "invalid node class: Con"

[Tobias Hartmann]

On Mon, 2 Feb 2026 17:52:09 GMT, Quan Anh Mai <qamai at openjdk.org> wrote:

> Hi,
> 
> I cannot manage to reproduce the issue, and it seems to fail only once in our CI. From the log, it seems that the issue is due to the fact that the pointer input to the `Load` is a `Proj` but its input dies, so the cast `as_Multi` in `try_optimize_strict_final_load_memory` fails. I can see a similar check in `MemNode::optimize_simple_memory_chain`. As a result, it is reasonable to just return the top here.
> 
> Please take a look and leave your review, thanks a lot.

That looks reasonable to me. Could you please try to re-enable the tests marked with `// TODO 8325632`? See my comment in [JDK-8325632](https://bugs.openjdk.org/browse/JDK-8325632) for details.

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

PR Review: https://git.openjdk.org/valhalla/pull/2016#pullrequestreview-3743976424