> This PR proposes to rewrite the `StringSupport::chunkedStrlen*` methods, > fixing a bug in the `short_strlen` variant for odd offsets (`offset % 2 != > 0`). > > This PR also improves performance on modern hardware, as there is no need for > pre-looping alignment. Removing this improves performance by about 30% for > larger strings. > > It passes the `jdk_foreign` test suit. Also, `tier1` through `tier3` passes > on various platforms and configurations. > > Base: > > > 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 > InternalStrLen.elementByteMisaligned 251 avgt 30 126.644 ? 0.902 > ns/op...
Per Minborg has updated the pull request incrementally with one additional commit since the last revision: Add zero detection method for quad words ------------- Changes: - all: https://git.openjdk.org/jdk/pull/22451/files - new: https://git.openjdk.org/jdk/pull/22451/files/2a788868..7ab520d4 Webrevs: - full: https://webrevs.openjdk.org/?repo=jdk&pr=22451&range=05 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=22451&range=04-05 Stats: 8 lines in 1 file changed: 7 ins; 0 del; 1 mod Patch: https://git.openjdk.org/jdk/pull/22451.diff Fetch: git fetch https://git.openjdk.org/jdk.git pull/22451/head:pull/22451 PR: https://git.openjdk.org/jdk/pull/22451
