RFR: 8255493: Support for pre-generated java.lang.invoke classes in CDS dynamic archive

[Yumin Qi]

On Thu, 22 Apr 2021 06:03:35 GMT, David Holmes <dholmes at openjdk.org> wrote:

>> Hi, Please review
>> 
>>   When do dynamic dump, the pre-generated lambda form classes from java.lang.invoke are not stored in dynamic archive. The patch will regenerate the four holder classes, 
>>      "java.lang.invoke.Invokers$Holder",
>>      "java.lang.invoke.DirectMethodHandle$Holder",
>>      "java.lang.invoke.DelegatingMethodHandle$Holder",
>>      "java.lang.invoke.LambdaForm$Holder"
>>   which will include the versions in static archive and new loaded functions all together and stored in dynamic archive. New test case added.
>>   (Minor change to PrintSharedArchiveAtExit, which the index is not consecutive)
>> 
>>   Tests: tier1,tier2,tier3,tier4
>>   
>>   Thanks
>>   Yumin
>
> src/hotspot/share/memory/dynamicArchive.cpp line 374:
> 
>> 372:   if (LambdaFormInvokers::should_regenerate_holder_classes()) {
>> 373:     JavaThread* THREAD = JavaThread::current();
>> 374:     assert(THREAD->is_Java_thread(), "Should be JavaThread");
> 
> JavaThread::current() already asserts this.

Will remove the assert.
I will also move the check should_regenerate_holder_classes to LambdaFormInvokers::should_regenerate_holder_classes().

> src/hotspot/share/memory/dynamicArchive.cpp line 376:
> 
>> 374:     assert(THREAD->is_Java_thread(), "Should be JavaThread");
>> 375:     log_info(cds, dynamic)("Regenerate lambdaform holder classes ...");
>> 376:     LambdaFormInvokers::regenerate_holder_classes(THREAD);
> 
> What if this throws an exception?

If there is exception in java side to regenerate the holder classes, there is a log for cds to indicate the regeneration failed, the exception is cleared and continue. It will not affect other parts.

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

PR: https://git.openjdk.java.net/jdk/pull/3611