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25 package jdk.internal.foreign.abi;
26 
27 import jdk.incubator.foreign.MemoryAddress;
28 import jdk.incubator.foreign.MemorySegment;
29 import jdk.internal.foreign.ResourceScopeImpl;
30 import jdk.internal.foreign.NativeMemorySegmentImpl;
31 
32 public class UpcallStubs {
33 
upcallAddress(UpcallHandler handler, ResourceScopeImpl scope)34     public static MemoryAddress upcallAddress(UpcallHandler handler, ResourceScopeImpl scope) {
35         long stubAddress = handler.entryPoint();
36         return NativeMemorySegmentImpl.makeNativeSegmentUnchecked(MemoryAddress.ofLong(stubAddress), 0,
37                 () -> freeUpcallStub(stubAddress), scope).address();
38     }
39 
freeUpcallStub(long stubAddress)40     private static void freeUpcallStub(long stubAddress) {
41         if (!freeUpcallStub0(stubAddress)) {
42             throw new IllegalStateException("Not a stub address: " + stubAddress);
43         }
44     }
45 
46     // natives
47 
48     // returns true if the stub was found (and freed)
freeUpcallStub0(long addr)49     private static native boolean freeUpcallStub0(long addr);
50 
registerNatives()51     private static native void registerNatives();
52     static {
registerNatives()53         registerNatives();
54     }
55 }
56