On Thu, 15 May 2025 21:04:40 GMT, Archie Cobbs <aco...@openjdk.org> wrote:
>> Please review this small performance tweak `ArrayDeque`. >> >> `ArrayDeque` has an invariant in which any unused elements in the array must >> be null. In a couple of places, the code is setting contiguous ranges of >> elements to null using `for()` loops. This can be both simplified and sped >> up by using `Arrays.fill()` instead. > > Archie Cobbs has updated the pull request incrementally with one additional > commit since the last revision: > > Blackhole ArrayDeque to ensure it's not ignored by the compiler. I'm closing the PR because it's gone into low-level optimization details that are beyond me. However I'm still unclear on whether bulk memory set operations are being fully optimized. By that I mean doing [something like this](https://git.zx2c4.com/glibc/commit/?id=cec3aef32412779e207f825db0d057ebb4628ae8) on arm64 at least. Any insights from the experts would be appreciated. Thanks for the interesting discussion. ------------- PR Comment: https://git.openjdk.org/jdk/pull/25237#issuecomment-2887858521
