RFR: 8247536: Support for pre-generated java.lang.invoke classes in CDS static archive [v11]

[Mandy Chung]

On Tue, 6 Oct 2020 17:35:18 GMT, Yumin Qi <minqi at openjdk.org> wrote:

>> This patch is reorganized after 8252725, which is separated from this patch to refactor jlink glugin code. The previous
>> webrev with hg can be found at: http://cr.openjdk.java.net/~minqi/2020/8247536/webrev-05. With 8252725 integrated, the
>> regeneration of holder classes is simply to call the new added GenerateJLIClassesHelper.cdsGenerateHolderClasses
>> function.  Tests: tier1-4
>
> Yumin Qi has updated the pull request incrementally with one additional commit since the last revision:
> 
>   Removed unused imports.

src/java.base/share/classes/java/lang/invoke/GenerateJLIClassesHelper.java line 63:

> 61:             if (TRACE_RESOLVE) {
> 62:                 System.out.println(traceLF + (resolvedMember != null ? " (success)" : " (fail)"));
> 63:             }

I suggest not to change the existing code.  Instead, have `CDS::traceLambdaFormInvoker`
to take individual parameters `Class<?> holder, String name, String shortenSignature`
(rather than the formatted string).   Something like:

    if (CDS.isDumpLoadedClassList()) {
          CDS.traceLambdaFormInvoker(holder, name, shortenSignature(basicTypeSignature(type));
    }

This also gives flexibility to CDS to decide on what format to write to the class list (like this case, you drop the
text "success/fail")

In addition, the conditional check on `CDS.isDumpLoadedClassList()` is hard to relate to why CDS traces these events.
I see Ioi's comment on this method name too.   I agree with Ioi that `isDumpingClassList` makes more sense.

src/java.base/share/classes/java/lang/invoke/GenerateJLIClassesHelper.java line 74:

> 72:                 System.out.println(traceSP + (salvage != null ? " (salvaged)" : " (generated)"));
> 73:             }
> 74:             CDS.traceLambdaFormInvoker(traceSP);

I suggest leaving the existing code unchanged.  Instead, add the following:
    if (CDS.isDumpingClassList()) {
         CDS.traceSpeciesType(cn);
    }

The above uses Ioi's suggested method name which reads better.

src/java.base/share/classes/jdk/internal/misc/CDS.java line 83:

> 81:      * check if -XX:+DumpLoadedClassList and given file is open
> 82:      */
> 83:     public static boolean isDumpLoadedClassList() {

I agree with Ioi's suggestion to rename this to `isDumpingClassList` which describes what the VM is doing.

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

PR: https://git.openjdk.java.net/jdk/pull/193