[9] RFR (XS): 8078290: Customize adapted MethodHandle in MH.invoke() case

[John Rose]

Reviewed. Nice find. 

– John

> On Apr 21, 2015, at 10:37 AM, Vladimir Ivanov <vladimir.x.ivanov at oracle.com> wrote:
> 
> http://cr.openjdk.java.net/~vlivanov/8078290/webrev.00/
> https://bugs.openjdk.java.net/browse/JDK-8078290
> 
> Customization logic introduced in [1] doesn't work as expected for MH.invoke() when asType() conversion happens and cached MH is used.
> 
> Generic invoker LambdaForm looks like:
> 
> invoke_002_MT=Lambda(a0:L,a1:L,a2:L)=>{
>    t3:L=Invokers.checkGenericType(a0:L,a2:L);
>    t4:V=Invokers.checkCustomized(a0:L);
>    t5:L=MethodHandle.invokeBasic(t3:L,a1:L);t5:L}
> }
> 
> Original MH(a0) is customized, but adapted MH (t3) is used for invocation. a0 != t3 when MH.asType() conversion happens in Invokers.checkGenericType().
> 
> Invoker LambdaForm should have the following structure:
> 
> invoke_002_MT=Lambda(a0:L,a1:L,a2:L)=>{
>    t3:L=Invokers.checkGenericType(a0:L,a2:L);
>    t4:V=Invokers.checkCustomized(t3:L);
>    t5:L=MethodHandle.invokeBasic(t3:L,a1:L);t5:L}
> }
> 
> Testing: manual (verified invoker LF), microbenchmark, jdk/test/java/lang/invoke, hotspot/test/compiler/jsr292, nashorn
> 
> Best regards,
> Vladimir Ivanov