On Thu, 2 Oct 2025 16:16:44 GMT, Kerman <[email protected]> wrote: >> Implement JEP 526: Lazy Constants (Second Preview) >> >> The lazy list/map implementations are broken out from `ImmutableCollections` >> to a separate class. >> >> The old benchmarks are not moved/renamed to allow comparison with previous >> releases. >> >> `java.util.Optional` is updated so that its field is annotated with >> `@Stable`. This is to allow `Optional` instances to be held in lazy >> constants and still provide constant folding. > > src/java.base/share/classes/java/util/Optional.java line 74: > >> 72: * If non-null, the value; if null, indicates no value is present >> 73: */ >> 74: @Stable > > Shouldn’t this also add a null sentinel to allow the folding of the empty > case? Or is that irrelevant because empty would be the terminator of a chain.
Usually a null sentinel is used when null indicates something different. I think maybe to allow folding the empty case, we should probably add a new annotation or a new element-value to indicate this status and properly handle it in C1/C2 (similar to the field trusting in ciField) ------------- PR Review Comment: https://git.openjdk.org/jdk/pull/27605#discussion_r2403729792
