> This change add 3 new methods in Objects: > > public static long checkIndex(long index, long length) > public static long checkFromToIndex(long fromIndex, long toIndex, long length) > public static long checkFromIndexSize(long fromIndex, long size, long length) > > This mirrors the int utility methods that were added by JDK-8135248 > with the same motivations. > > As is the case with the int checkIndex(), the long checkIndex() method > is JIT compiled as an intrinsic. It allows the JIT to compile > checkIndex to an unsigned comparison and properly recognize it as > a range check that then becomes a candidate for the existing range check > optimizations. This has proven to be important for panama's > MemorySegment API and a prototype of this change (with some extra c2 > improvements) showed that panama micro benchmark results improve > significantly. > > This change includes: > > - the API change > - the C2 intrinsic > - tests for the API and the C2 intrinsic > > This is a joint work with Paul who reviewed and reworked the API change > and filled the CSR.
Roland Westrelin has updated the pull request incrementally with one additional commit since the last revision: intrinsic comments ------------- Changes: - all: https://git.openjdk.java.net/jdk/pull/1003/files - new: https://git.openjdk.java.net/jdk/pull/1003/files/b47184ac..aaacd328 Webrevs: - full: https://webrevs.openjdk.java.net/?repo=jdk&pr=1003&range=02 - incr: https://webrevs.openjdk.java.net/?repo=jdk&pr=1003&range=01-02 Stats: 4 lines in 1 file changed: 4 ins; 0 del; 0 mod Patch: https://git.openjdk.java.net/jdk/pull/1003.diff Fetch: git fetch https://git.openjdk.java.net/jdk pull/1003/head:pull/1003 PR: https://git.openjdk.java.net/jdk/pull/1003
