On Mon, 26 Jan 2026 07:20:40 GMT, Damon Fenacci <[email protected]> wrote:
>> # Issue >> >> The Valhalla test >> `compiler/valhalla/inlinetypes/TestArrayCopy.java#AlwaysIncrementalInline` >> crashes intermittently in `ProjNode::adr_type()` when asserting `adr_type != >> nullptr`. >> >> # Cause >> >> We are in the process of cleaning up an unreacheable subgraph and we get to >> a situation like this one: >> >> <img width="427" height="336" alt="Screenshot 2026-01-20 at 19 57 31" >> src="https://github.com/user-attachments/assets/c040b647-0858-4cc9-af68-5a1b05cc58fb"; >> /> >> >> We have a Tuple node with top inputs followed by memory projection. Later in >> the same ideal loop, while running Ideal for the `MemoryMerge` node, we >> query the type of its memory Proj input, which skips the Tuple here: >> >> https://github.com/openjdk/valhalla/blob/b2f45e0f857fb32bdc36e7b93346ebc967b74736/src/hotspot/share/opto/multnode.cpp#L151-L154 >> >> and returns its corresponding input (`2`), which is top (and its `adr_type` >> returns `nullptr`) >> >> # Fix >> >> We should probably check for `ctrl` being top (for this situation) >> additionally to `nullptr`. >> >> # Testing >> >> Tier 1-3+ >> Failing test before and after. > > Damon Fenacci has updated the pull request incrementally with one additional > commit since the last revision: > > JDK-8374911: copyright year Looks good to me. FTR: Damon explained in the JBS comments why this does not show up in mainline. We discussed offline and agreed to put this fix only in Valhalla for now. ------------- Marked as reviewed by thartmann (Committer). PR Review: https://git.openjdk.org/valhalla/pull/1944#pullrequestreview-3704866681
