On Mon, 25 May 2026 05:03:22 GMT, Jatin Bhateja <[email protected]> wrote:
>> Add a new Float16lVector type and corresponding concrete vector classes, in >> addition to existing primitive vector types, maintaining operation parity >> with the FloatVector type. >> - Add necessary inline expander support. >> - Enable intrinsification for a few vector operations, namely >> ADD/SUB/MUL/DIV/MAX/MIN/SQRT/FMA. >> - Use existing Float16 vector IR and backend support. >> - Extended the existing VectorAPI JTREG test suite for the newly added >> Float16Vector operations. >> >> The idea here is to first be at par with Float16 auto-vectorization support >> before intrinsifying new operations (conversions, reduction, etc). >> >> The following are the performance numbers for some of the selected >> Float16Vector benchmarking kernels compared to equivalent auto-vectorized >> Float16OperationsBenchmark kernels. >> >> <img width="1344" height="532" alt="image" >> src="https://github.com/user-attachments/assets/c8157c3c-22b0-4bc1-9de9-7a68cadb7b2a"; >> /> >> >> Initial RFP[1] was floated on the panama-dev mailing list. >> >> Kindly review the draft PR and share your feedback. >> >> Best Regards, >> Jatin >> >> [1] https://mail.openjdk.org/pipermail/panama-dev/2025-August/021100.html >> >> --------- >> - [x] I confirm that I make this contribution in accordance with the >> [OpenJDK Interim AI Policy](https://openjdk.org/legal/ai). > > Jatin Bhateja has updated the pull request incrementally with one additional > commit since the last revision: > > Changes to accomodate CSR feedback src/jdk.incubator.vector/share/classes/jdk/incubator/vector/Float16Vector.java line 825: > 823: switch (opc_) { > 824: case VECTOR_OP_NEG: return (v0, m) -> > 825: v0.uOp(m, (i, a) -> (float) -a); I think we need to use `Float16.negate` as per the comments in the implementation of that method: public static Float16 negate(Float16 f16) { // Negate sign bit only. Per IEEE 754-2019 section 5.5.1, // negate is a bit-level operation and not a logical // operation. Therefore, in this case do _not_ use the float // unary minus as an implementation as that is not guaranteed // to flip the sign bit of a NaN. return shortBitsToFloat16((short)(f16.value ^ SIGN_BIT_MASK)); } We would also need to update tests, specifically the `scalar_neg` method to call `Float16.negate`. ------------- PR Review Comment: https://git.openjdk.org/jdk/pull/28002#discussion_r3306921641
