[jdk21u-dev] RFR: 8353175: Eliminate double iteration of stream in FieldDescriptor reinitialization

[Radim Vansa]

On Fri, 31 Oct 2025 09:59:31 GMT, Goetz Lindenmaier <goetz at openjdk.org> wrote:

>> This backport is a partial fix for a performance regression and prerequisite for backport of https://github.com/openjdk/jdk/pull/24847 (will be done through https://github.com/rvansa/jdk21u-dev/tree/refs/heads/rvansa/backport-8352075)
>> 
>> The backport was not clean; a notable new change is in `reflectionUtils.hpp` (later JDK versions remove the affected class) - I am adding `friend class FieldStream` to `InstanceKlass` to accomodate for this.
>> 
>> Backport-of: f169fc5a99ee2b485e156c043134ab76b7e5ebd9
>
> HI @rvansa 
> What is the state of this?  In case you want to integrate, please at least rerun GHA by merging head.

@GoeLin Thanks for the ping - yes, I'd still like to integrate this, merged head and the GHA checks are passing. Is the change mature enough in 25 to admit this into 21?

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PR Comment: https://git.openjdk.org/jdk21u-dev/pull/2010#issuecomment-3480729725