RFR: 8353786: Migrate Vector API math library support to FFM API [v2]

[Vladimir Ivanov]

> 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:

  Reviews and Float64Vector-related fix

-------------

Changes:
  - all: https://git.openjdk.org/jdk/pull/24462/files
  - new: https://git.openjdk.org/jdk/pull/24462/files/fc27aee5..368b943e

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk&pr=24462&range=01
 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=24462&range=00-01

  Stats: 22 lines in 2 files changed: 5 ins; 6 del; 11 mod
  Patch: https://git.openjdk.org/jdk/pull/24462.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/24462/head:pull/24462

PR: https://git.openjdk.org/jdk/pull/24462