RFR: 8287442: Reduce list to array conversions in java.lang.invoke.MethodHandles

[liach]

On Fri, 27 May 2022 14:18:19 GMT, Claes Redestad <redestad at openjdk.org> wrote:

> In preparation of #8855 this PR refactors the conversions from `List` to array and array to `List`, reducing the number of conversions when calling `MethodHandles.dropArguments` in particular. This remove about ~5% of allocations on the `StringConcatFactoryBootstraps` microbenchmark.

If `parameterList` is too slow for `List.of` copies the backing parameter types array, wouldn't calling `JavaUtilCollectionAccess::listFromTrustedArray` a better alternative, as it only allocates one wrapper and has better performance on `subList` than `Arrays.copyOfRange`?

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PR: https://git.openjdk.java.net/jdk/pull/8923