> By avoiding a bit shift operation for the latin1 fast-path test, we can speed > up the `java.lang.CharacterData.of` method by ~25% for latin1 code points. > > The latin1 test is currently implemented as `ch >>> 8 == 0`. We can replace > this with `ch >= 0 && ch <= 0xFF` for a noticable performance gain > (especially for Latin1 code points): > > This method is called frequently by various property-determining methods in > `java.lang.Character` like `isLowerCase`, `isDigit` etc, so one should expect > improvements for all these methods. > > Performance is tested using the `Characters.isDigit` benchmark using the > digits '0' (decimal 48, in CharacterDataLatin1) and '\u0660' (decimal 1632, > in CharacterData00): > > Baseline: > > > Benchmark (codePoint) Mode Cnt Score Error Units > Characters.isDigit 48 avgt 15 0.870 ± 0.011 ns/op > Characters.isDigit 1632 avgt 15 2.168 ± 0.017 ns/op > > PR: > > > Benchmark (codePoint) Mode Cnt Score Error Units > Characters.isDigit 48 avgt 15 0.654 ± 0.007 ns/op > Characters.isDigit 1632 avgt 15 2.032 ± 0.019 ns/op
Eirik Bjorsnos has updated the pull request incrementally with one additional commit since the last revision: Update StringLatin1.canEncode to sync with same test in CharacterData.of ------------- Changes: - all: https://git.openjdk.org/jdk/pull/13040/files - new: https://git.openjdk.org/jdk/pull/13040/files/0174440e..0baf690e Webrevs: - full: https://webrevs.openjdk.org/?repo=jdk&pr=13040&range=01 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=13040&range=00-01 Stats: 1 line in 1 file changed: 0 ins; 0 del; 1 mod Patch: https://git.openjdk.org/jdk/pull/13040.diff Fetch: git fetch https://git.openjdk.org/jdk pull/13040/head:pull/13040 PR: https://git.openjdk.org/jdk/pull/13040
