Fix bug with adaptation support and non-crackable direct handles

openjdk · May 18, 2020 · c4e734d · c4e734d
1 parent e2d2dba
commit c4e734d
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Showing 2 changed files with 40 additions and 11 deletions.
diff --git a/src/java.base/share/classes/java/lang/invoke/VarHandles.java b/src/java.base/share/classes/java/lang/invoke/VarHandles.java
@@ -542,17 +542,23 @@ public static VarHandle dropCoordinates(VarHandle target, int pos, Class<?>... v
     private static void noCheckedExceptions(MethodHandle handle) {
         if (handle instanceof DirectMethodHandle) {
             DirectMethodHandle directHandle = (DirectMethodHandle)handle;
-            MethodHandleInfo info = MethodHandles.Lookup.IMPL_LOOKUP.revealDirect(directHandle);
-            Class<?>[] exceptionTypes = switch (info.getReferenceKind()) {
-                case MethodHandleInfo.REF_invokeInterface, MethodHandleInfo.REF_invokeSpecial,
-                        MethodHandleInfo.REF_invokeStatic, MethodHandleInfo.REF_invokeVirtual ->
-                        info.reflectAs(Method.class, MethodHandles.Lookup.IMPL_LOOKUP).getExceptionTypes();
-                case MethodHandleInfo.REF_newInvokeSpecial ->
-                        info.reflectAs(Constructor.class, MethodHandles.Lookup.IMPL_LOOKUP).getExceptionTypes();
-                case MethodHandleInfo.REF_getField, MethodHandleInfo.REF_getStatic,
-                        MethodHandleInfo.REF_putField, MethodHandleInfo.REF_putStatic -> null;
-                default -> throw new AssertionError("Cannot get here");
-            };
+            byte refKind = directHandle.member.getReferenceKind();
+            MethodHandleInfo info = new InfoFromMemberName(
+                    MethodHandles.Lookup.IMPL_LOOKUP,
+                    directHandle.member,
+                    refKind);
+            final Class<?>[] exceptionTypes;
+            if (MethodHandleNatives.refKindIsMethod(refKind)) {
+                exceptionTypes = info.reflectAs(Method.class, MethodHandles.Lookup.IMPL_LOOKUP)
+                        .getExceptionTypes();
+            } else if (MethodHandleNatives.refKindIsField(refKind)) {
+                exceptionTypes = null;
+            } else if (MethodHandleNatives.refKindIsConstructor(refKind)) {
+                exceptionTypes = info.reflectAs(Constructor.class, MethodHandles.Lookup.IMPL_LOOKUP)
+                        .getExceptionTypes();
+            } else {
+                throw new AssertionError("Cannot get here");
+            }
             if (exceptionTypes != null) {
                 if (Stream.of(exceptionTypes).anyMatch(VarHandles::isCheckedException)) {
                     throw newIllegalArgumentException("Cannot adapt a var handle with a method handle which throws checked exceptions");

diff --git a/test/jdk/java/foreign/TestAdaptVarHandles.java b/test/jdk/java/foreign/TestAdaptVarHandles.java
@@ -49,6 +49,8 @@ public class TestAdaptVarHandles {
 
     static MethodHandle S2I;
     static MethodHandle I2S;
+    static MethodHandle O2I;
+    static MethodHandle I2O;
     static MethodHandle S2L;
     static MethodHandle S2L_EX;
     static MethodHandle S2I_EX;
@@ -61,6 +63,8 @@ public class TestAdaptVarHandles {
         try {
             S2I = MethodHandles.lookup().findStatic(TestAdaptVarHandles.class, "stringToInt", MethodType.methodType(int.class, String.class));
             I2S = MethodHandles.lookup().findStatic(TestAdaptVarHandles.class, "intToString", MethodType.methodType(String.class, int.class));
+            O2I = MethodHandles.explicitCastArguments(S2I, MethodType.methodType(int.class, Object.class));
+            I2O = MethodHandles.explicitCastArguments(I2S, MethodType.methodType(Object.class, int.class));
             S2L = MethodHandles.lookup().findStatic(TestAdaptVarHandles.class, "stringToLong", MethodType.methodType(long.class, String.class));
             S2L_EX = MethodHandles.lookup().findStatic(TestAdaptVarHandles.class, "stringToLongException", MethodType.methodType(long.class, String.class));
             BASE_ADDR = MethodHandles.lookup().findStatic(TestAdaptVarHandles.class, "baseAddress", MethodType.methodType(MemoryAddress.class, MemorySegment.class));
@@ -98,6 +102,25 @@ public void testFilterValue() throws Throwable {
         assertEquals(value, "42");
     }
 
+    @Test
+    public void testFilterValueLoose() throws Throwable {
+        ValueLayout layout = MemoryLayouts.JAVA_INT;
+        MemorySegment segment = MemorySegment.allocateNative(layout);
+        VarHandle intHandle = layout.varHandle(int.class);
+        VarHandle i2SHandle = MemoryHandles.filterValue(intHandle, O2I, I2O);
+        i2SHandle.set(segment.baseAddress(), "1");
+        String oldValue = (String)i2SHandle.getAndAdd(segment.baseAddress(), "42");
+        assertEquals(oldValue, "1");
+        String value = (String)i2SHandle.get(segment.baseAddress());
+        assertEquals(value, "43");
+        boolean swapped = (boolean)i2SHandle.compareAndSet(segment.baseAddress(), "43", "12");
+        assertTrue(swapped);
+        oldValue = (String)i2SHandle.compareAndExchange(segment.baseAddress(), "12", "42");
+        assertEquals(oldValue, "12");
+        value = (String)(Object)i2SHandle.toMethodHandle(VarHandle.AccessMode.GET).invokeExact(segment.baseAddress());
+        assertEquals(value, "42");
+    }
+
     @Test(expectedExceptions = NullPointerException.class)
     public void testBadFilterNullTarget() {
         MemoryHandles.filterValue(null, S2I, I2S);