[GR-37155] Support ClassLoader.getClassLoadingLock

PullRequest: graal/11175

Author: vjovanov

substratevm/src/com.oracle.svm.core/src/com/oracle/svm/core/annotate/RecomputeFieldValue.java

@@ -60,6 +60,11 @@ enum Kind {
          * default constructor.
          */
         NewInstance,
+        /**
+         * The object field is set to a instance of {@link #declClass} created by calling the
+         * default constructor when the target field value is not null.
+         */
+        NewInstanceWhenNotNull,
         /**
          * The field is set to the value assigned to the {@link Alias} field.
          */

substratevm/src/com.oracle.svm.core/src/com/oracle/svm/core/jdk/Target_java_lang_ClassLoader.java

@@ -74,7 +74,7 @@ public final class Target_java_lang_ClassLoader {
     @Alias @RecomputeFieldValue(kind = Kind.Reset)//
     private Vector<Class<?>> classes;
 
-    @Alias @RecomputeFieldValue(kind = Kind.Reset)//
+    @Alias @RecomputeFieldValue(kind = Kind.NewInstanceWhenNotNull, declClass = ConcurrentHashMap.class)//
     private ConcurrentHashMap<String, Object> parallelLockMap;
 
     /**
@@ -187,12 +187,6 @@ Class<?> loadClass(Module module, String name) {
         }
     }
 
-    @Substitute //
-    @SuppressWarnings({"unused"})
-    Object getClassLoadingLock(String className) {
-        throw VMError.unsupportedFeature("Target_java_lang_ClassLoader.getClassLoadingLock(String)");
-    }
-
     @Substitute //
     @SuppressWarnings({"unused"}) //
     private Class<?> findLoadedClass0(String name) {

substratevm/src/com.oracle.svm.hosted/src/com/oracle/svm/hosted/substitute/ComputedValueField.java

@@ -316,13 +316,14 @@ public JavaConstant readValue(MetaAccessProvider metaAccess, JavaConstant receiv
     private JavaConstant computeValue(MetaAccessProvider metaAccess, JavaConstant receiver) {
         SnippetReflectionProvider originalSnippetReflection = GraalAccess.getOriginalSnippetReflection();
         JavaConstant result;
+        Object originalValue;
         switch (kind) {
+            case NewInstanceWhenNotNull:
+                originalValue = fetchOriginalValue(metaAccess, receiver, originalSnippetReflection);
+                result = originalValue == null ? originalSnippetReflection.forObject(null) : createNewInstance(originalSnippetReflection);
+                break;
             case NewInstance:
-                try {
-                    result = originalSnippetReflection.forObject(ReflectionUtil.newInstance(targetClass));
-                } catch (ReflectionUtilError ex) {
-                    throw VMError.shouldNotReachHere("Error performing field recomputation for alias " + annotated.format("%H.%n"), ex.getCause());
-                }
+                result = createNewInstance(originalSnippetReflection);
                 break;
             case AtomicFieldUpdaterOffset:
                 result = computeAtomicFieldUpdaterOffset(metaAccess, receiver);
@@ -336,13 +337,7 @@ private JavaConstant computeValue(MetaAccessProvider metaAccess, JavaConstant re
                 if (customValueProvider instanceof CustomFieldValueComputer) {
                     newValue = ((CustomFieldValueComputer) customValueProvider).compute(metaAccess, original, annotated, receiverValue);
                 } else if (customValueProvider instanceof CustomFieldValueTransformer) {
-                    JavaConstant originalValueConstant = ReadableJavaField.readFieldValue(metaAccess, GraalAccess.getOriginalProviders().getConstantReflection(), original, receiver);
-                    Object originalValue;
-                    if (originalValueConstant.getJavaKind().isPrimitive()) {
-                        originalValue = originalValueConstant.asBoxedPrimitive();
-                    } else {
-                        originalValue = originalSnippetReflection.asObject(Object.class, originalValueConstant);
-                    }
+                    originalValue = fetchOriginalValue(metaAccess, receiver, originalSnippetReflection);
                     newValue = ((CustomFieldValueTransformer) customValueProvider).transform(metaAccess, original, annotated, receiverValue, originalValue);
                 } else {
                     throw UserError.abort("The custom field value computer class %s does not implement %s or %s", targetClass.getName(),
@@ -360,6 +355,27 @@ private JavaConstant computeValue(MetaAccessProvider metaAccess, JavaConstant re
         return result;
     }
 
+    private JavaConstant createNewInstance(SnippetReflectionProvider originalSnippetReflection) {
+        JavaConstant result;
+        try {
+            result = originalSnippetReflection.forObject(ReflectionUtil.newInstance(targetClass));
+        } catch (ReflectionUtilError ex) {
+            throw VMError.shouldNotReachHere("Error performing field recomputation for alias " + annotated.format("%H.%n"), ex.getCause());
+        }
+        return result;
+    }
+
+    private Object fetchOriginalValue(MetaAccessProvider metaAccess, JavaConstant receiver, SnippetReflectionProvider originalSnippetReflection) {
+        JavaConstant originalValueConstant = ReadableJavaField.readFieldValue(metaAccess, GraalAccess.getOriginalProviders().getConstantReflection(), original, receiver);
+        Object originalValue;
+        if (originalValueConstant.getJavaKind().isPrimitive()) {
+            originalValue = originalValueConstant.asBoxedPrimitive();
+        } else {
+            originalValue = originalSnippetReflection.asObject(Object.class, originalValueConstant);
+        }
+        return originalValue;
+    }
+
     private void putCached(JavaConstant receiver, JavaConstant result) {
         if (disableCaching) {
             return;