During work on #12453 @schlosna reported that `array.clone()` might underperform `System.arraycopy` in microbenchmarks and I opted to go with `arraycopy` throughout while investigating.
Testing on x86 (SandyBridge, AVX2) I observe no difference at all between the setups. On aarch the only difference I can observe is that arraycopy seem curiously slow for input size = 0, otherwise no statistically significant difference. All tests ran on builds from JDK mainline and 21-b9. Since the reported difference was small and mostly visible on very large arrays I conclude that the maintainability win we get from using `clone()` is preferable. I've added the microbenchmark provided by @schlosna here. ------------- Commit messages: - Examine arraycopy vs clone Changes: https://git.openjdk.org/jdk/pull/12613/files Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=12613&range=00 Issue: https://bugs.openjdk.org/browse/JDK-8302315 Stats: 163 lines in 2 files changed: 92 ins; 55 del; 16 mod Patch: https://git.openjdk.org/jdk/pull/12613.diff Fetch: git fetch https://git.openjdk.org/jdk pull/12613/head:pull/12613 PR: https://git.openjdk.org/jdk/pull/12613
