> This PR proposes to fix a performance regression (on x64 platforms) for > 32-bit strings introduced by > [JDK-8345120](https://bugs.openjdk.org/browse/JDK-8345120). > > The PR also fixes a performance regression in the benchmarks caused by using > the wrong type for `MemorySegment`. > > Regrettably, this PR uses different code paths for various architectures. > This gives optimum performance for all platforms at the expense of slightly > more code complexity. > > Base (macOS, M1) (Before https://github.com/openjdk/jdk/pull/22451) > > > Benchmark (size) Mode Cnt Score Error > Units > InternalStrLen.changedElementQuad 1 avgt 30 2.057 ? 0.012 > ns/op > InternalStrLen.changedElementQuad 4 avgt 30 3.776 ? 0.031 > ns/op > InternalStrLen.changedElementQuad 16 avgt 30 6.690 ? 0.060 > ns/op > InternalStrLen.changedElementQuad 251 avgt 30 48.581 ? 0.764 > ns/op > InternalStrLen.changedElementQuad 1024 avgt 30 196.188 ? 3.484 > ns/op > InternalStrLen.chunkedDouble 1 avgt 30 1.903 ? 0.013 > ns/op > InternalStrLen.chunkedDouble 4 avgt 30 3.446 ? 0.025 > ns/op > InternalStrLen.chunkedDouble 16 avgt 30 5.759 ? 0.062 > ns/op > InternalStrLen.chunkedDouble 251 avgt 30 26.892 ? 0.141 > ns/op > InternalStrLen.chunkedDouble 1024 avgt 30 72.940 ? 1.562 > ns/op > InternalStrLen.chunkedSingle 1 avgt 30 1.897 ? 0.015 > ns/op > InternalStrLen.chunkedSingle 4 avgt 30 5.357 ? 0.560 > ns/op > InternalStrLen.chunkedSingle 16 avgt 30 3.821 ? 0.052 > ns/op > InternalStrLen.chunkedSingle 251 avgt 30 19.482 ? 0.190 > ns/op > InternalStrLen.chunkedSingle 1024 avgt 30 38.938 ? 0.411 > ns/op > InternalStrLen.chunkedSingleMisaligned 1 avgt 30 2.230 ? 0.147 > ns/op > InternalStrLen.chunkedSingleMisaligned 4 avgt 30 5.424 ? 0.688 > ns/op > InternalStrLen.chunkedSingleMisaligned 16 avgt 30 9.573 ? 0.063 > ns/op > InternalStrLen.chunkedSingleMisaligned 251 avgt 30 22.242 ? 0.182 > ns/op > InternalStrLen.chunkedSingleMisaligned 1024 avgt 30 45.442 ? 0.252 > ns/op > InternalStrLen.elementByteMisaligned 1 avgt 30 1.616 ? 0.041 > ns/op > InternalStrLen.elementByteMisaligned 4 avgt 30 2.982 ? 0.018 > ns/op > InternalStrLen.elementByteMisaligned 16 avgt 30 8.662 ? 0.085 > ns/op > InternalStrLe...
Per Minborg has updated the pull request incrementally with one additional commit since the last revision: Improve short string cases ------------- Changes: - all: https://git.openjdk.org/jdk/pull/22539/files - new: https://git.openjdk.org/jdk/pull/22539/files/4d41488b..96c3a55c Webrevs: - full: https://webrevs.openjdk.org/?repo=jdk&pr=22539&range=02 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=22539&range=01-02 Stats: 63 lines in 1 file changed: 53 ins; 0 del; 10 mod Patch: https://git.openjdk.org/jdk/pull/22539.diff Fetch: git fetch https://git.openjdk.org/jdk.git pull/22539/head:pull/22539 PR: https://git.openjdk.org/jdk/pull/22539
