Fixed the bug where if a caller keeps a reference to the array passed into `MethodTypeDesc.of`, the caller may mutate the Desc via the array and can create invalid MethodTypeDesc.
Unfortunately, since the input array now needs to be copied, the `of` factory suffers from a performance drop. But otherwise, this patch has minor performance gains on `ofDescriptor` factory, even compared to Adam's patch that optimized `ofDescriptor` in #12945. This patch moves the parameters to an immutable list, to avoid allocations on `parameterList` as well. Benchmark of Oracle JDK 20: https://gist.github.com/683c6219e183cbc2b336224fc2c0d50a Benchmark of this patch: https://gist.github.com/22be9371a2370fb4a7b44f1684750ec4 Benchmark of [asotona's patch](https://github.com/openjdk/jdk/pull/12945/files#diff-ac8e413d3e13532a2b0d34a90253c6ddd7a4f04082f792b9d076e9b5a33f2078): https://gist.github.com/eb98579c3b51cafae481049a95a78f80 [sotona vs this](https://jmh.morethan.io/?gists=eb98579c3b51cafae481049a95a78f80,22be9371a2370fb4a7b44f1684750ec4); [20 vs this](https://jmh.morethan.io/?gists=683c6219e183cbc2b336224fc2c0d50a,22be9371a2370fb4a7b44f1684750ec4); [20 vs sotona](https://jmh.morethan.io/?gists=683c6219e183cbc2b336224fc2c0d50a,eb98579c3b51cafae481049a95a78f80), for reference ------------- Commit messages: - Add benchmark - 8304932: MethodTypeDescImpl can be mutated by argument passed to MethodTypeDesc.of Changes: https://git.openjdk.org/jdk/pull/13186/files Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=13186&range=00 Issue: https://bugs.openjdk.org/browse/JDK-8304932 Stats: 314 lines in 5 files changed: 155 ins; 87 del; 72 mod Patch: https://git.openjdk.org/jdk/pull/13186.diff Fetch: git fetch https://git.openjdk.org/jdk.git pull/13186/head:pull/13186 PR: https://git.openjdk.org/jdk/pull/13186
