RFR: 8286669: Replace MethodHandle specialization with ASM in mainline [v2]

[Maurizio Cimadamore]

On Fri, 13 May 2022 13:23:41 GMT, Jorn Vernee <jvernee at openjdk.org> wrote:

>> Hi,
>> 
>> This PR brings over commits from the panama-foreign repo. These commits mostly pertain to the switch to ASM and away from MethodHandle combinators for the binding recipe specialization. But, there is one more commit which adds freeing of downcall stubs, since those changes were mostly Java as well.
>> 
>> Thanks,
>> Jorn
>> 
>> Testing: `run-test-jdk_foreign` with `-Dgenerator.sample.factor=-1` on Windows and Linux.
>
> Jorn Vernee has updated the pull request incrementally with one additional commit since the last revision:
> 
>   Use unaligned layout constants when filling in reconstituted structs (was accidentally dropped change)

src/java.base/share/classes/jdk/internal/foreign/abi/CallingSequence.java line 109:

> 107:      * @return the caller method type.
> 108:      */
> 109:     public MethodType callerMethodType() {

Would it make sense to either rename these, or to point to the fact that these are equivalent to Linker::downcallType/upcallType ?

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

PR: https://git.openjdk.java.net/jdk/pull/8685