On Thu, 6 Apr 2023 17:18:22 GMT, Chen Liang <li...@openjdk.org> wrote:

>> As John Rose has pointed out in this issue, the current j.l.r.Proxy based 
>> implementation of MethodHandleProxies.asInterface has a few issues:
>> 1. Exposes too much information via Proxy supertype (and WrapperInstance 
>> interface)
>> 2. Does not allow future expansion to support SAM[^1] abstract classes
>> 3. Slow (in fact, very slow)
>> 
>> This patch addresses all 3 problems:
>> 1. It implements proxies with one hidden class for each requested interface 
>> and replaced WrapperInstance inheritance with an annotation. This can avoid 
>> unexpected passing of `instanceof`, and avoids the nasty problem of 
>> exporting a JDK interface to a dynamic module to ensure access.
>> 2. This patch obtains already generated classes from a ClassValue by the 
>> requested interface type; the ClassValue can later be updated to compute 
>> implementation generation for abstract classes as well.
>> 3. This patch's generated hidden classes has call performance on par with 
>> those of lambda expressions; the creation performance is slightly less than 
>> that of LambdaMetafactory: 
>> https://jmh.morethan.io/?gist=fcb946d83ee4ac7386901795ca49b224
>> 
>> Additionally, an obsolete `ProxyForMethodHandle` test was removed, for it's 
>> no longer applicable. Tests in `jdk/java/lang/invoke` and 
>> `jdk/java/lang/reflect` pass.
>> 
>> In addition, I have a question: in 
>> [8161245](https://bugs.openjdk.org/browse/JDK-8161245) it seems some fields 
>> can be optimized as seen in 
>> [ciField.cpp](https://github.com/openjdk/jdk/blob/6aec6f3a842ead30b26cd31dc57a2ab268f67875/src/hotspot/share/ci/ciField.cpp#L219).
>>  Does it affect the execution performance of MethodHandle in hidden classes' 
>> Condy vs. MethodHandle in regular final field in hidden classes?
>> 
>> [^1]: single abstract method
>
> Chen Liang 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 17 additional commits since 
> the last revision:
> 
>  - Nuke WrapperInstance
>  - Merge branch 'master' into explore/mhp-iface
>  - Whitespace, cleanup, rename benchmarks to be informative
>  - Address review comments
>    
>    Make sure it runs with SecurityManager
>    Split the benchmarks
>  - Use a dumper for interface instances, other cleanup
>  - Merge branch 'master' into explore/mhp-iface
>  - Merge branch 'master' into explore/mhp-iface
>  - Remove unused JavaLangReflectReflectAccess.invokeDefault
>  - rethrow error
>  - Benchmark compareing to lamda metafactory, various minor updates
>  - ... and 7 more: https://git.openjdk.org/jdk/compare/d7a90082...3fe36fd6

If you run the test with the system property on, it's dumped in the scratch 
directory.   Do you run with jtreg command?

-------------

PR Comment: https://git.openjdk.org/jdk/pull/13197#issuecomment-1499438370

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