On Thu, 8 Aug 2024 06:50:59 GMT, Jatin Bhateja <jbhat...@openjdk.org> wrote:
> Hi All, > > As per the discussion on panama-dev mailing list[1], patch adds the support > for following new vector operators. > > > . SUADD : Saturating unsigned addition. > . SADD : Saturating signed addition. > . SUSUB : Saturating unsigned subtraction. > . SSUB : Saturating signed subtraction. > . UMAX : Unsigned max > . UMIN : Unsigned min. > > > New vector operators are applicable to only integral types since their values > wraparound in over/underflowing scenarios after setting appropriate status > flags. For floating point types, as per IEEE 754 specs there are multiple > schemes to handler underflow, one of them is gradual underflow which > transitions the value to subnormal range. Similarly, overflow implicitly > saturates the floating-point value to an Infinite value. > > As the name suggests, these are saturating operations, i.e. the result of the > computation is strictly capped by lower and upper bounds of the result type > and is not wrapped around in underflowing or overflowing scenarios. > > Summary of changes: > - Java side implementation of new vector operators. > - Add new scalar saturating APIs for each of the above saturating vector > operator in corresponding primitive box classes, fallback implementation of > vector operators is based over it. > - C2 compiler IR and inline expander changes. > - Optimized x86 backend implementation for new vector operators and their > predicated counterparts. > - Extends existing VectorAPI Jtreg test suite to cover new operations. > > Kindly review and share your feedback. > > Best Regards, > PS: Intrinsification and auto-vectorization of new core-lib API will be > addressed separately in a follow-up patch. > > [1] https://mail.openjdk.org/pipermail/panama-dev/2024-May/020408.html This pull request has now been integrated. Changeset: 52382e28 Author: Jatin Bhateja <jbhat...@openjdk.org> URL: https://git.openjdk.org/jdk/commit/52382e285fdf853c01605f8e0d7f3f5d34965802 Stats: 9395 lines in 52 files changed: 8959 ins; 29 del; 407 mod 8338021: Support new unsigned and saturating vector operators in VectorAPI Reviewed-by: psandoz, epeter, sviswanathan ------------- PR: https://git.openjdk.org/jdk/pull/20507
