This PR suggests we add a vectorized equalsIgnoreCase benchmark to the set of benchmarks in `org.openjdk.bench.jdk.incubator.vector`. This benchmark serves as an example of how vectorization can be useful also in the area of text processing. It takes advantage of the fact that ASCII and Latin-1 were designed to optimize case-twiddling operations.
The code came about during the work on #12632, where vectorization was deemed out of scope. Benchmark results: Benchmark (size) Mode Cnt Score Error Units EqualsIgnoreCaseBenchmark.scalar 16 avgt 15 20.671 ± 0.718 ns/op EqualsIgnoreCaseBenchmark.scalar 32 avgt 15 46.155 ± 3.258 ns/op EqualsIgnoreCaseBenchmark.scalar 64 avgt 15 68.248 ± 1.767 ns/op EqualsIgnoreCaseBenchmark.scalar 128 avgt 15 148.948 ± 0.890 ns/op EqualsIgnoreCaseBenchmark.scalar 1024 avgt 15 1090.708 ± 7.540 ns/op EqualsIgnoreCaseBenchmark.vectorized 16 avgt 15 21.872 ± 0.232 ns/op EqualsIgnoreCaseBenchmark.vectorized 32 avgt 15 11.378 ± 0.097 ns/op EqualsIgnoreCaseBenchmark.vectorized 64 avgt 15 13.703 ± 0.135 ns/op EqualsIgnoreCaseBenchmark.vectorized 128 avgt 15 21.632 ± 0.735 ns/op EqualsIgnoreCaseBenchmark.vectorized 1024 avgt 15 105.509 ± 7.493 ns/op ------------- Commit messages: - Remove references to 'the oldest ASCII trick in the book' - Merge branch 'master' into vectorized-equalsignorecase - Fix "using applying" - Benchmark for exploring a vectorized latin1 equalsIgnoreCase Changes: https://git.openjdk.org/jdk/pull/12790/files Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=12790&range=00 Issue: https://bugs.openjdk.org/browse/JDK-8303401 Stats: 152 lines in 1 file changed: 152 ins; 0 del; 0 mod Patch: https://git.openjdk.org/jdk/pull/12790.diff Fetch: git fetch https://git.openjdk.org/jdk pull/12790/head:pull/12790 PR: https://git.openjdk.org/jdk/pull/12790
