Attached Test.java used to fail with -XX:+VerifyAdapterSharing due to false sharing of the adapters for MyValue1::test and MyValue2:test. The problem is that both methods have a byte "receiver" but with different offsets. I added code to InlineKlass::collect_fields to detect this situation and add some "garbage" to the signature to distinguish it from a "local" field with a different offset. I'm not 100% convinced though that this is correct, so we should investigate in more detail. Do we need different "garbage"? Could an empty inline type produce the same signature?

See https://github.com/openjdk/valhalla/blob/714930ee3b79eea215a475a770bcf0544ca4780f/src/hotspot/share/oops/inlineKlass.cpp#L421-L424

Update: Attached Test2.java which currently fails.