[riscv-port-jdk17u:riscv-port] RFR: 8287425: Remove unnecessary register push for MacroAssembler::check_klass_subtype_slow_path

[Fei Yang]

On Thu, 16 Mar 2023 04:34:39 GMT, Xiaolin Zheng <xlinzheng at openjdk.org> wrote:

> This is another-half backport (RISC-V part only) of [JDK-8287425](https://bugs.openjdk.org/browse/JDK-8287425). The original patch is at [1].
> 
> This patch can interestingly fix an issue with async-profiler [2], and has been backported to JDK17/JDK11u. But when backporting to JDK17, the RISC-V part of this patch was dropped [3] since we did not have the RISC-V backend. Now that we have the RISC-V port of JDK17, the missing part needs a backport as well.
> 
> Tested on unmatched, hotspot tier1~2 (fastdebug). More tiers are on the way.
> 
> [1] https://github.com/openjdk/jdk/commit/b5a646ee6cfd432cef6b7e69a177959227a38ace
> [2] https://github.com/jvm-profiling-tools/async-profiler/issues/673#issuecomment-1316738564
> [3] https://github.com/openjdk/jdk17u-dev/pull/672

Looks fine. Thanks.

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Marked as reviewed by fyang (Committer).

PR: https://git.openjdk.org/riscv-port-jdk17u/pull/16