RFR: 8265518: C1: Intrinsic support for Preconditions.checkIndex [v4]

Yi Yang yyang at openjdk.java.net
Thu Apr 29 02:53:18 UTC 2021

> 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:

  remove extra newline


  - all: https://git.openjdk.java.net/jdk/pull/3615/files
  - new: https://git.openjdk.java.net/jdk/pull/3615/files/db8b6ef4..bbdf4b9e

 - full: https://webrevs.openjdk.java.net/?repo=jdk&pr=3615&range=03
 - incr: https://webrevs.openjdk.java.net/?repo=jdk&pr=3615&range=02-03

  Stats: 1 line in 1 file changed: 0 ins; 1 del; 0 mod
  Patch: https://git.openjdk.java.net/jdk/pull/3615.diff
  Fetch: git fetch https://git.openjdk.java.net/jdk pull/3615/head:pull/3615

PR: https://git.openjdk.java.net/jdk/pull/3615

More information about the hotspot-compiler-dev mailing list