On Wed, 23 Apr 2025 23:54:01 GMT, Vladimir Ivanov <vliva...@openjdk.org> wrote:
>> Migrate Vector API math library (SVML and SLEEF) linkage from native code >> (in JVM) to Java FFM API. >> >> Since FFM API doesn't support vector calling conventions yet, migration >> affects only symbol lookup for now. But it still enables significant >> simplifications on JVM side. >> >> The patch consists of the following parts: >> * on-demand symbol lookup in Java code replaces eager lookup from native >> code during JVM startup; >> * 2 new VM intrinsics for vector calls (support unary and binary shapes) >> (code separated from unary/binary vector operations); >> * new internal interface to query supported CPU ISA extensions >> (`jdk.incubator.vector.CPUFeatures`) used for CPU dispatching. >> >> `java.lang.foreign` API is used to perform symbol lookup in vector math >> library, then the address is cached and fed into corresponding JVM >> intrinsic, so C2 can turn it into a direct vector call in generated code. >> >> Once `java.lang.foreign` supports vectors & vector calling conventions, VM >> intrinsics can go away. >> >> Performance is on par with original implementation (tested with >> microbenchmarks on linux-x64 and macosx-aarch64). >> >> Testing: hs-tier1 - hs-tier6, microbenchmarks (on linux-x64 and >> macosx-aarch64) >> >> Thanks! > > Vladimir Ivanov has updated the pull request incrementally with one > additional commit since the last revision: > > CPUFeatures: RISC-V support src/hotspot/share/opto/vectorIntrinsics.cpp line 563: > 561: debug_name = > debug_name_oop->const_oop()->as_instance()->java_lang_String_str(buf, buflen); > 562: } > 563: Node* vcall = make_runtime_call(RC_VECTOR, By generating an upfront CallLeafVectorNode, we may miss out on performing any GVN-style optimization for trigonometric identities like the following. do you think creating a macro node which can lazily be expanded to call node during macro expansion will help. arcsin(sin(x)) => x arccos(cos(x)) => x sin(arcsin(x) => x cos(arccos(x) => x ------------- PR Review Comment: https://git.openjdk.org/jdk/pull/24462#discussion_r2059057257
