RFR: 8295302: Do not use ArrayList when LambdaForm has a single ClassData [v3]

[Mandy Chung]

On Mon, 17 Oct 2022 21:48:42 GMT, Ioi Lam <iklam at openjdk.org> wrote:

>> Please review this small optimization. As shown in the JBS issue, most of the generated LambdaForm classes have a single ClassData, so we can get a small footprint/speed improvement.
>
> Ioi Lam has updated the pull request with a new target base due to a merge or a rebase. The incremental webrev excludes the unrelated changes brought in by the merge/rebase. The pull request contains four additional commits since the last revision:
> 
>  - Merge branch 'master' into 8295302-no-arraylist-for-single-classdata-for-lambdaform
>  - @mlchung comments
>  - @iwanowww comments
>  - 8295302: Do not use ArrayList when LambdaForm has a single ClassData

Thanks for the update.    I made the suggested wording.   You can push once it's updated.

src/java.base/share/classes/java/lang/invoke/InvokerBytecodeGenerator.java line 346:

> 344: 
> 345:     /**
> 346:      * Returns an object to pass this.classData to the <clinit> method of the

What about:

Suggestion:

     * Returns the class data object that will be passed to `Lookup.defineHiddenClass`.
     * The classData is loaded in the <clinit> method of the generated class.
     * If the class data contains only one single object, this method returns  that single object.
     * If the class data contains more than one objects, this method returns a List.
     *
     * This method returns null if no class data.

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Marked as reviewed by mchung (Reviewer).

PR: https://git.openjdk.org/jdk/pull/10706