[code-reflection] RFR: Make sure method parameters keep their slots when lowering [v2]

[Paul Sandoz]

On Sat, 27 Jan 2024 08:12:06 GMT, Hannes Greule <hgreule at openjdk.org> wrote:

>> Previously, unused method parameters didn't get a slot, resulting in either wrong results or bad classfiles.
>> 
>> I propose a simple fix: Make sure that all parameters of the entry block get a slot, in the order they are defined.
>> I didn't want to change too much code here, so I decided to add a boolean flag to indicate that even values without uses get a slot.
>> If you have a better idea or more plans on this, please let me know.
>> 
>> I also added multiple test cases showcasing the issue: One that results in the wrong value returned, one with a type mismatch resulting in a VerifyError, and one with a type mismatch due to being non-static, also causing a VerifyError (this is the case that made me discover this issue).
>> 
>> I ran the tests in `langtools/tools/javac/reflect/` and `java/lang/reflect/code/` to make sure they all (still) pass.
>
> Hannes Greule has updated the pull request incrementally with one additional commit since the last revision:
> 
>   apply suggestions

Looks good. As you have noticed this area will change, for the better!, so localized fixes are best and may be relevant (esp. tests).

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Marked as reviewed by psandoz (Lead).

PR Review: https://git.openjdk.org/babylon/pull/8#pullrequestreview-1849230503