RFR: 8341587: [premain] Support Soft/Weak Reference in AOT cache [v2]

[Chen Liang]

On Wed, 19 Feb 2025 16:54:47 GMT, Mat Carter <macarte at openjdk.org> wrote:

>> src/java.base/share/classes/java/lang/invoke/MethodTypeForm.java line 134:
>> 
>>> 132:     @SuppressWarnings({"rawtypes", "unchecked"})
>>> 133:     public LambdaForm cachedLambdaForm(int which) {
>>> 134:         Object entry = lambdaForms[which];
>> 
>> I recommend restoring the static types of the arrays to `SoftReference<MethodHandle>[]` unless there is extra overhead from loading/initialization of `SoftReference` class.
>
> I tried this before but then 'this.methodHandles = new SoftReference<MethodHandle>[MH_LIMIT];' is not allowed due to the error 'generic array creation'.  I looked at allocating using ArrayList<>(initialCapacity) as they are backed. with Object[], but then we have to add range checks on the reads to avoid IndexOutOfBounds or set a null entry at (initialCapacity-1); unless someone can suggest a better implementation I'm inclined to let it stand

You can try like `(SoftReference<MethodHandle>[]) new SoftReference<?>[MH_LIMIT]`, and add `@SuppressWarnings("unchecked")` on the constructors.

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PR Review Comment: https://git.openjdk.org/leyden/pull/41#discussion_r1962066401