On Wed, 22 Feb 2023 20:01:52 GMT, Eirik Bjorsnos <d...@openjdk.org> wrote:
>> This PR suggests we can speed up `StringLatin1.regionMatchesCI` by applying >> 'the oldest ASCII trick in the book'. >> >> The new static method `CharacterDataLatin1.equalsIgnoreCase` compares two >> latin1 bytes for equality ignoring case. `StringLatin1.regionMatchesCI` is >> updated to use `equalsIgnoreCase` >> >> To verify the correctness of `equalsIgnoreCase`, a new test is added to >> `EqualsIgnoreCase` with an exhaustive verification that all 256x256 latin1 >> code point pairs have an `equalsIgnoreCase` consistent with >> Character.toUpperCase, Character.toLowerCase. >> >> Performance is tested for matching and mismatching cases of code point pairs >> picked from the ASCII letter, ASCII number and latin1 letter ranges. Results >> in the first comment below. > > Eirik Bjorsnos has updated the pull request with a new target base due to a > merge or a rebase. The incremental webrev excludes the unrelated changes > brought in by the merge/rebase. The pull request contains 21 additional > commits since the last revision: > > - Merge branch 'master' into regionmatches-latin1-speedup > - Merge branch 'master' into regionmatches-latin1-speedup > - Make the loop variables chars to avoid casting > - Use improved case-twiddling comment as suggested by Martin > - Replace 'oldest ASCII trick in the book' use in toUpperCase, toLowerCase > with "by removing (setting) a single bit" > - Align local variable naming in toLowerCase, toUpperCase with > equalsIgnoreCase by using 'lower' and 'upper' > - Rename unconventionally named local variable 'U' to 'upper' > - Merge remote-tracking branch 'origin/master' into > regionmatches-latin1-speedup > - Add whitespace between methods > - Merge branch 'master' into regionmatches-latin1-speedup > - ... and 11 more: https://git.openjdk.org/jdk/compare/6e269b24...597b346a Marked as reviewed by alanb (Reviewer). ------------- PR: https://git.openjdk.org/jdk/pull/12632
