On Thu, 3 Oct 2024 05:09:22 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 two vector permutation APIs. >> >> >> Declaration:- >> Vector<E>.selectFrom(Vector<E> v1, Vector<E> v2) >> >> >> Semantics:- >> Using index values stored in the lanes of "this" vector, assemble the >> values stored in first (v1) and second (v2) vector arguments. Thus, first >> and second vector serves as a table, whose elements are selected based on >> index value vector. API is applicable to all integral and floating-point >> types. The result of this operation is semantically equivalent to >> expression v1.rearrange(this.toShuffle(), v2). Values held in index vector >> lanes must lie within valid two vector index range [0, 2*VLEN) else an >> IndexOutOfBoundException is thrown. >> >> Summary of changes: >> - Java side implementation of new selectFrom API. >> - C2 compiler IR and inline expander changes. >> - In absence of direct two vector permutation instruction in target ISA, a >> lowering transformation dismantles new IR into constituent IR supported by >> target platforms. >> - Optimized x86 backend implementation for AVX512 and legacy target. >> - Function tests covering new API. >> >> JMH micro included with this patch shows around 10-15x gain over existing >> rearrange API :- >> Test System: Intel(R) Xeon(R) Platinum 8480+ [ Sapphire Rapids Server] >> >> >> Benchmark (size) Mode Cnt >> Score Error Units >> SelectFromBenchmark.rearrangeFromByteVector 1024 thrpt 2 2041.762 >> ops/ms >> SelectFromBenchmark.rearrangeFromByteVector 2048 thrpt 2 1028.550 >> ops/ms >> SelectFromBenchmark.rearrangeFromIntVector 1024 thrpt 2 962.605 >> ops/ms >> SelectFromBenchmark.rearrangeFromIntVector 2048 thrpt 2 479.004 >> ops/ms >> SelectFromBenchmark.rearrangeFromLongVector 1024 thrpt 2 359.758 >> ops/ms >> SelectFromBenchmark.rearrangeFromLongVector 2048 thrpt 2 178.192 >> ops/ms >> SelectFromBenchmark.rearrangeFromShortVector 1024 thrpt 2 1463.459 >> ops/ms >> SelectFromBenchmark.rearrangeFromShortVector 2048 thrpt 2 727.556 >> ops/ms >> SelectFromBenchmark.selectFromByteVector 1024 thrpt 2 33254.830 >> ops/ms >> SelectFromBenchmark.selectFromByteVector 2048 thrpt 2 17313.174 >> ops/ms >> SelectFromBenchmark.selectFromIntVector 1024 thrpt 2 10756.804 >> ops/ms >> S... > > Jatin Bhateja has updated the pull request with a new target base due to a > merge or a rebase. The pull request now contains 18 commits: > > - Review comments resolution. > - Merge branch 'master' of http://github.com/openjdk/jdk into JDK-8338023 > - Review comments resolutions. > - Handling NPOT vector length for AArch64 SVE with vector sizes varying b/w > 128 and 2048 bits at 128 bit increments. > - Incorporating review and documentation suggestions. > - Jcheck clearance > - Review comments resolution. > - Disabling VectorLoadShuffle bypassing optimization to comply with > rearrange semantics at IR level. > - Documentation suggestions from Paul. > - Review resolutions. > - ... and 8 more: https://git.openjdk.org/jdk/compare/bdfb41f9...6215ab91 Thanks for making the changes. It looks to me that the following checks at lines 2963-2071 in file vectorIntrinsics.cpp is now only needed when lowerSelectFromOp is false. Could you please verify and update accordingly? if (is_floating_point_type(elem_bt)) { if (!arch_supports_vector(Op_AndV, num_elem, index_elem_bt, VecMaskNotUsed) || !arch_supports_vector(cast_vopc, num_elem, index_elem_bt, VecMaskNotUsed) || !arch_supports_vector(Op_Replicate, num_elem, index_elem_bt, VecMaskNotUsed)) { log_if_needed(" ** index wrapping not supported: vlen=%d etype=%s" , num_elem, type2name(elem_bt)); return false; // not supported } } ------------- PR Comment: https://git.openjdk.org/jdk/pull/20508#issuecomment-2392036048
