[lworld] RFR: 8369045: [lworld] valhalla/valuetypes/WeakReferenceTest.java has an unschedulable graph [v4]

[Damon Fenacci]

On Mon, 15 Dec 2025 09:42:15 GMT, Damon Fenacci <dfenacci at openjdk.org> wrote:

>> That's a possibility. I've also considered checking for `!C->inlining_incrementally() && C->late_inline_count() > 0` but I'm a bit torn between being 100% sure we are doing strength reduction but using a compile "flags" (a bit 🫤) and checking for other, already available, conditions (like the one you suggest), which make me a bit unsure and could potentially change in the future...
>> But I guess introducing a new field to `Compile` just for this should be avoided. So, let's go for `_gvn.is_IterGVN() && !C->inlining_incrementally()` 🙂
>
> Fixed.

I spoke too soon: `_gvn` is actually set when the `GraphKit` is created (when generating the call) and is not using the context of the call being strength-reduced. So, unfortunately it seems that the least-invasive way to figure out if we are strength-reducing is to have a compile flag. I reverted the change.

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PR Review Comment: https://git.openjdk.org/valhalla/pull/1768#discussion_r2627124461