On Wed, 13 Mar 2024 16:02:29 GMT, Chen Liang <li...@openjdk.org> wrote:
>> Shaojin Wen has updated the pull request incrementally with one additional >> commit since the last revision: >> >> bug fix for CharArraySequence > > src/java.base/share/classes/java/math/BigDecimal.java line 561: > >> 559: index += offset; >> 560: if (index >= length) >> 561: throw new IndexOutOfBoundsException(); > > This logic is wrong: if offset is 3 and length is 2, aab*bc*c would be valid, > but your code will IOOBE on `charAt(0)` because `index += offset` will be 3, > 3 > 2. > > You should use `Objects.checkIndex(index, length)` instead. Oh, what a stupid mistake :) Using Objects.checkIndex will have a redundant check for index < 0, which does not need to be done in this scenario. Objects.checkIndex will cause a slight performance degradation. The performance numbers under MacBookPro M1 Max are as follows: Benchmark Mode Cnt Score Error Units BigDecimals.testConstructorWithSmallCharArray avgt 15 19.167 ? 0.070 ns/op Benchmark Mode Cnt Score Error Units # Objects.checkIndex BigDecimals.testConstructorWithSmallCharArray avgt 15 20.591 ? 0.241 ns/op ------------- PR Review Comment: https://git.openjdk.org/jdk/pull/18177#discussion_r1524049182
