review request (L): 6939224 MethodHandle.invokeGeneric needs to perform the correct set of conversions

[John Rose]

6939224: MethodHandle.invokeGeneric needs to perform the correct set of conversions

Until now, the HotSpot JVM has conflated invokeExact with invokeGeneric.  These changes, combined with forthcoming JDK runtime support changes, provide a hook for the JVM to perform on-the-fly argument conversions in invokeGeneric calls, as specified by the JSR 292 EG.

http://cr.openjdk.java.net/~jrose/6939224/webrev.00/

This review is for the JDK parts, which (a) distinguishes correctly between the two invocation modes, and (b) performs an upcall to Java code when argument types need matching.

-- John