RFR: 8330388: Remove invokedynamic cache index encoding [v2]

[Coleen Phillimore]

On Thu, 18 Apr 2024 16:22:31 GMT, Matias Saavedra Silva <matsaave at openjdk.org> wrote:

>> Before [JDK-8307190](https://bugs.openjdk.org/browse/JDK-8307190), [JDK-8309673](https://bugs.openjdk.org/browse/JDK-8309673), and [JDK-8301995](https://bugs.openjdk.org/browse/JDK-8301995), invokedynamic operands needed to be rewritten to encoded values to better distinguish indy entries from other cp cache entries. The above changes now distinguish between entries with `to_cp_index()` using the bytecode, which is now propagated by the callers.
>> 
>> The encoding flips the bits of the index so the encoded index is always negative, leading to access errors if there is no matching decode call. These calls are removed with some methods adjusted to distinguish between indices with the bytecode. Verified with tier 1-5 tests. The changes show no issues when tested against libgraal.
>
> Matias Saavedra Silva has updated the pull request incrementally with one additional commit since the last revision:
> 
>   Dean and Gilles comments

Still good!

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Marked as reviewed by coleenp (Reviewer).

PR Review: https://git.openjdk.org/jdk/pull/18819#pullrequestreview-2015844122