On Fri, 8 Apr 2022 01:05:33 GMT, Srinivas Vamsi Parasa <d...@openjdk.java.net> wrote:
>> Optimizes the divideUnsigned() and remainderUnsigned() methods in >> java.lang.Integer and java.lang.Long classes using x86 intrinsics. This >> change shows 3x improvement for Integer methods and upto 25% improvement for >> Long. This change also implements the DivMod optimization which fuses >> division and modulus operations if needed. The DivMod optimization shows 3x >> improvement for Integer and ~65% improvement for Long. > > Srinivas Vamsi Parasa has updated the pull request incrementally with one > additional commit since the last revision: > > uncomment zero in integer div, mod test Personally, I think the optimisation for `div < 0` should be handled by the mid-end optimiser, which will not only give us the advantages of dead code elimination, but also global code motion. I would suggest the backend only doing `xorl rdx, rdx; divl $div$$Register` and the optimisation for `div < 0` will be implemented as a part of JDK-8282365. What do you think? Thanks. ------------- PR: https://git.openjdk.java.net/jdk/pull/7572
