RFR: 8247666: Support Lambda proxy classes in static CDS archive [v5]

[Calvin Cheung]

On Fri, 16 Oct 2020 21:25:04 GMT, Mandy Chung <mchung at openjdk.org> wrote:

>> `@lambda-proxy LambHello run ()Ljava/lang/Runnable; ()V REF_invokeStatic LambHello lambda$main$0 ()V ()V`
>> means
>> `@lambda-proxy <classname> <intf-method-name> <intf-method-sig> <bsm-arg0> <bsm-arg1a> <bsm-arg1b>  <bsm-arg1c> 
>> <bsm-arg1d> <bsm-arg2>`
>> It is a symbolic representation of a invoke dynamic constant pool entry.
>> public class LambHello {
>>     public static void main(String[] args) {
>>         doit(() -> {
>>             System.out.println("Hello from Lambda");
>>         });
>>     }
>>     static void doit(Runnable t) {
>>         t.run();
>>     }
>> }
>> 
>> An invoke dynamic constant pool of the above program is:
>> ` -   7 : InvokeDynamic : bootstrap_method_index=43 name_and_type_index=8 arguments={50, 51, 50}`
>> Other constant pool entries related to the above are:
>>  -   8 : NameAndType : name_index=9 signature_index=10
>>  -   9 : Utf8 : 'run'
>>  -  10 : Utf8 : '()Ljava/lang/Runnable;'
>> 
>>  -  50 : MethodType : signature_index=6
>>  -  51 : MethodHandle : ref_kind=6 ref_index=52
>>  -  52 : Method : klass_index=12 name_and_type_index=53
>>  -  53 : NameAndType : name_index=39 signature_index=6
>> 
>>  -   6 : Utf8 : '()V'
>>  -  12 : Class : 'LambHello' {0x0000000800c10040}
>>  -  39 : Utf8 : 'lambda$main$0'
>> The info included in the class list are:
>>     <classname>                  = LambHello
>>     <intf-method-name>     = run
>>     <intf-method-sig>         = ()Ljava/lang/Runnable;
>>     <bsm-arg0>                   = ()V
>>     <bsm-arg1a>                  = REF_invokeStatic
>>     <bsm-arg1b>                  = LambHello
>>     <bsm-arg1c>                  = lambda$main$0
>>     <bsm-arg1d>                  = ()V
>>     <bsm-arg2>                   = ()V
>
> Since the class list file is not intended for users to edit/modify but rather a configuration file given
> when -Xshare:dump is used, the format of `@lambda-proxy` entry is internal implementation details and so it's fine.
> BTW:  for the method handle reference kind, does the entry have the value (e.g. 6) or the name ("REF_invokeStatic")?
> I see both formats are described in your different replies.
>> @lambda-proxy: LambHello run ()Ljava/lang/Runnable; ()V 6 LambHello lambda$main$0 ()V ()V
> or
>> @lambda-proxy LambHello run ()Ljava/lang/Runnable; ()V REF_invokeStatic LambHello lambda$main$0 ()V ()V

For the reference kind, the first format (with number '6') will be stored in the classlist.

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PR: https://git.openjdk.java.net/jdk/pull/364