Conform to spec for MethodHandles::loop's with void return types

[ThanHenderson]

This patch fixes eclipse-openj9/openj9#18293; which is really a duplicate of eclipse-openj9/openj9#11937. 'loop' in OJDK MHs does not conform to the spec w.r.t. setting loop finalizers for loop's with void return types. This patch properly sets default finalizer values.

The patch conforms to the spec: https://docs.oracle.com/en/java/javase/11/docs/api/java.base/java/lang/invoke/MethodHandles.html#loop(java.lang.invoke.MethodHandle[]...) for 3.d

Closes: eclipse-openj9/openj9#18293 Signed-off-by: Nathan Henderson nathan.henderson@ibm.com

[ThanHenderson]

My reasoning for diagnosis was eerily exactly the same as https://github.com/eclipse-openj9/openj9/issues/11937#issuecomment-856086725

Unfortunately, for times sake, I had only discovered the previous issue and PR after I had found the solution.

This will not need to be implemented in JDK8 since MethodHandles.loop does not exist therein.

[ThanHenderson]

ping: @babsingh

[babsingh]

This is a backport of https://github.com/ibmruntimes/openj9-openjdk-jdk16/pull/58.

[babsingh]

jenkins test sanity.functional,sanity.openjdk xlinuxojdk292 jdk11

[babsingh]

Only known issues are seen in the PR builds, which are unrelated to the PR:

• https://github.com/eclipse-openj9/openj9/issues/17576
• https://github.com/eclipse-openj9/openj9/issues/10330