On Wed, 9 Jun 2021 08:53:40 GMT, Yi Yang <yy...@openjdk.org> wrote: >> The JDK codebase re-created many variants of checkIndex(`grep -I -r >> 'cehckIndex' jdk/`). A notable variant is java.nio.Buffer.checkIndex, which >> annotated with @IntrinsicCandidate and it only has a corresponding C1 >> intrinsic version. >> >> In fact, there is an utility method >> `jdk.internal.util.Preconditions.checkIndex`(wrapped by >> java.lang.Objects.checkIndex) that behaves the same as these variants of >> checkIndex, we can replace these re-created variants of checkIndex by >> Objects.checkIndex, it would significantly reduce duplicated code and enjoys >> performance improvement because Preconditions.checkIndex is >> @IntrinsicCandidate and it has a corresponding intrinsic method in HotSpot. >> >> But, the problem is currently HotSpot only implements the C2 version of >> Preconditions.checkIndex. To reuse it global-widely in JDK code, I think we >> can firstly implement its C1 counterpart. There are also a few kinds of >> stuff we can do later: >> >> 1. Replace all variants of checkIndex by Objects.checkIndex in the whole JDK >> codebase. >> 2. Remove Buffer.checkIndex and obsolete/deprecate InlineNIOCheckIndex flag >> >> Testing: cds, compiler and jdk > > Yi Yang has updated the pull request incrementally with one additional commit > since the last revision: > > more comment
Hi Yi, you may need to add the option to the obsolete-flags-table though as described in arguments.cpp: https://github.com/openjdk/jdk/blob/5cee23a9ed0b7fe2657be7492d9c1f78fcd02ebf/src/hotspot/share/runtime/arguments.cpp#L489-L490 I think the point is to give a customer a grace period where the option is still accepted on the command line. I am not sure if that step is optional though, if one is reasonably sure that the option is unused. Maybe @dholmes-ora can chime in. Cheers, Thomas ------------- PR: https://git.openjdk.java.net/jdk/pull/3615
