On Tue, 8 Sep 2020 20:42:41 GMT, rgiulietti <github.com+70726043+rgiulie...@openjdk.org> wrote:
>> src/java.base/share/classes/java/lang/Long.java line 1697: >> >>> 1695: final long q = (dividend >>> 1) / divisor << 1; >>> 1696: final long r = dividend - q * divisor; >>> 1697: return r - (~(r - divisor) >> Long.SIZE - 1 & divisor); >> >> Parentheses would be particularly helpful here. I'd certainly have to think >> hard about the relative precedences of >> `>>`, `-`, and `&`, whereas I wouldn't have to with: return r - ((~(r - >> divisor) >> (Long.SIZE - 1)) & divisor); >> >> I also think it would be worth adding a comment saying that this is >> deliberately `>>` not `>>>`, even though we have >> `>>>` in the divide method. Here we're propagating the sign bit so that >> `thing & divisor` is either 0 or `divisor` >> according as `thing` is –1 or 0. > > Hi Éamonn, > > I have no problems adding non-strictly needed parentheses. I usually don't > because I'm quite familiar with operator > precedence and often forget that other people are not. > I'll add comments for parts, like the one you point out, that are not already > discussed at length in the > bibliographical reference. > Thanks > Raffaello Hi, I just committed the changes. Greetings Raffaello ------------- PR: https://git.openjdk.java.net/jdk/pull/31
