On Fri, 21 Aug 2026 10:15:41 GMT, Dingli Zhang <[email protected]> wrote:
> Hi, please consider. > > This is a follow-up to > [JDK-8390101](https://bugs.openjdk.org/browse/JDK-8390101). > > On RISC-V, several VectorMask logical operations involving an all-bits-set > mask are currently emitted as sequences of multiple RVV mask instructions. > These include: > > - VectorMask.not() > - VectorMask.and(...).not() > - VectorMask.or(...).not() > - VectorMask.xor(...).not() > - VectorMask.eq() > - VectorMask.or(other.not()) > > RVV provides mask logical instructions that can implement these operations > directly. > > This change adds RISC-V C2 match rules to emit: > > - vmnot.m for mask NOT > - vmnand.mm for mask NAND > - vmnor.mm for mask NOR > - vmxnor.mm for mask XNOR and mask equality > - vmorn.mm for mask OR-NOT > > The rules cover byte, short, int, and long vector element types and replace > multi-instruction mask logical sequences with a single RVV mask instruction. > > ## Testing > > `MaskLogicOperationsBenchmark` on sg2044: > > > > Before After > Benchmark (size) Mode Cnt > Score Error Score Error Units > MaskLogicOperationsBenchmark.byteMaskEq 256 thrpt 10 > 9018.332 ± 80.876 12940.779 ± 1240.139 ops/ms > MaskLogicOperationsBenchmark.byteMaskEq 512 thrpt 10 > 4542.277 ± 474.059 6833.785 ± 852.424 ops/ms > MaskLogicOperationsBenchmark.byteMaskEq 1024 thrpt 10 > 2485.999 ± 23.447 3783.676 ± 37.133 ops/ms > MaskLogicOperationsBenchmark.byteMaskNand 256 thrpt 10 > 9239.545 ± 76.134 13712.414 ± 87.500 ops/ms > MaskLogicOperationsBenchmark.byteMaskNand 512 thrpt 10 > 4865.590 ± 33.147 7037.323 ± 138.414 ops/ms > MaskLogicOperationsBenchmark.byteMaskNand 1024 thrpt 10 > 2498.022 ± 32.932 3757.491 ± 68.019 ops/ms > MaskLogicOperationsBenchmark.byteMaskNor 256 thrpt 10 > 9234.898 ± 60.028 13362.605 ± 803.210 ops/ms > MaskLogicOperationsBenchmark.byteMaskNor 512 thrpt 10 > 4564.248 ± 389.177 7175.499 ± 183.598 ops/ms > MaskLogicOperationsBenchmark.byteMaskNor 1024 thrpt 10 > 2391.446 ± 128.692 3801.884 ± 61.826 ops/ms > MaskLogicOperationsBenchmark.byteMaskNot 256 thrpt 10 > 12136.710 ± 42.704 12737.138 ± 583.812 ops/ms > MaskLogicOperationsBenchmark.byteMaskNot 512 thrpt 10 > 6355.718 ± 31.723 7303.202 ± 163.445 ops/ms > MaskLogicOperationsBenchmark.byteMas... This pull request has now been integrated. Changeset: 393c3a02 Author: Dingli Zhang <[email protected]> URL: https://git.openjdk.org/jdk/commit/393c3a028ea6a88b90eaa2aee4f8ccf896aa1a4c Stats: 548 lines in 4 files changed: 546 ins; 0 del; 2 mod 8390826: RISC-V: Use dedicated vector mask logical instructions Reviewed-by: fyang, gcao ------------- PR: https://git.openjdk.org/jdk/pull/32480
