On Thu, 9 May 2024 15:00:35 GMT, Maurizio Cimadamore <mcimadam...@openjdk.org> wrote:
> Consider this layout: > > > MemoryLayout SEQ = MemoryLayout.sequenceLayout(5, > MemoryLayout.sequenceLayout(10, JAVA_INT)); > > > And the corresponding offset handle: > > > MethodHandle offsetHandle = SEQ.offsetHandle(PathElement.sequenceLayout(), > PathElement.sequenceLayout()); > > > The resulting method handle takes two additional `long` indices. The > implementation checks that the dynamically provided indices conform to the > bound available at construction: that is, the first index must be < 5, while > the second must be < 10. If this is not true, an `IndexOutOfBoundException` > is thrown. > > However, the javadoc for `MemoryLayout::byteOffsetHandle` doesn't claim > anything in this direction. There are only some vague claims in the javadoc > for `PathElement::sequenceElement()` and `PathElement::sequenceElement(long, > long, long)` which make some claims on which indices are actually allowed, > but the text seems more in the tone of a discussion, rather than actual > normative text. > > I've tweaked the javadoc for `MemoryLayout::byteOffsetHandle` to actually > state that the indices will be checked against the "size" of the > corresponding open path element (this is a new concept that I also have > defined in the javadoc). > > I also added a test for `byteOffsetHandle` as I don't think we had a test for > that specifically (although this method is tested indirectly, via > `MemoryLayout::varHandle`). This pull request has now been integrated. Changeset: 30bb066b Author: Maurizio Cimadamore <mcimadam...@openjdk.org> URL: https://git.openjdk.org/jdk/commit/30bb066b1982c5318d54bfe74115306c602e2974 Stats: 67 lines in 2 files changed: 61 ins; 0 del; 6 mod 8332003: Clarify javadoc for MemoryLayout::offsetHandle Reviewed-by: psandoz ------------- PR: https://git.openjdk.org/jdk/pull/19158
