On Tue, 14 Jan 2025 15:53:36 GMT, Shaojin Wen <s...@openjdk.org> wrote:
>> This is an optimization for decimal Integer.parseInt and Long.parseLong, >> which improves performance by about 10%. The optimization includes: >> 1. Improve performance by parsing 2 numbers at a time, which has performance >> improvements for numbers with length >= 3. >> 2. It uses charAt(0) for the first number. Assuming that the optimization >> can eliminate boundary checks, this will be more friendly to parsing numbers >> with length 1. >> 3. It removes the reliance on the Character.digit method and eliminates the >> reliance on the CharacterDataLatin1#DIGITS cache array, which avoids >> performance degradation caused by cache misses. > > Shaojin Wen has updated the pull request incrementally with two additional > commits since the last revision: > > - remove unused > - Update src/java.base/share/classes/jdk/internal/util/DecimalDigits.java > > Co-authored-by: Chen Liang <li...@openjdk.org> I might be wrong, but I think that `&&` are compiled down to conditionals? The code optimistically assumes that the string is parsable as an `int|long`, so `&` might lead to simpler machine code. Of course, if the benchmarks are good with `&&`, then please feel free to replace. ------------- PR Comment: https://git.openjdk.org/jdk/pull/22919#issuecomment-2613253311
