avoid duplicate but empty arrays

Author: wirthi

sdk/src/org.graalvm.nativeimage/src/org/graalvm/nativeimage/c/function/CFunctionPointer.java

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2013, 2019, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2013, 2025, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * The Universal Permissive License (UPL), Version 1.0

substratevm/src/com.oracle.graal.pointsto/src/com/oracle/graal/pointsto/meta/AnalysisMethod.java

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2012, 2024, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2012, 2025, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -119,6 +119,8 @@ public abstract class AnalysisMethod extends AnalysisElement implements WrappedJ
     private static final AtomicReferenceFieldUpdater<AnalysisMethod, Boolean> reachableInCurrentLayerUpdater = AtomicReferenceFieldUpdater
                     .newUpdater(AnalysisMethod.class, Boolean.class, "reachableInCurrentLayer");
 
+    public static final AnalysisMethod[] EMPTY_ARRAY = new AnalysisMethod[0];
+
     public record Signature(String name, AnalysisType[] parameterTypes) {
     }
 

substratevm/src/com.oracle.graal.pointsto/src/com/oracle/graal/pointsto/meta/AnalysisType.java

@@ -115,6 +115,8 @@ public abstract class AnalysisType extends AnalysisElement implements WrappedJav
 
     private static final AtomicReferenceFieldUpdater<AnalysisType, Object> RESOLVED_METHODS_UPDATER = AtomicReferenceFieldUpdater.newUpdater(AnalysisType.class, Object.class, "resolvedMethods");
 
+    public static final AnalysisType[] EMPTY_ARRAY = new AnalysisType[0];
+
     protected final AnalysisUniverse universe;
     private final ResolvedJavaType wrapped;
     private final String qualifiedName;
@@ -360,7 +362,7 @@ private AnalysisType[] convertTypes(ResolvedJavaType[] originalTypes) {
             }
             result.add(universe.lookup(originalType));
         }
-        return result.toArray(new AnalysisType[result.size()]);
+        return result.toArray(AnalysisType.EMPTY_ARRAY);
     }
 
     public AnalysisType getArrayClass(int dim) {

substratevm/src/com.oracle.graal.pointsto/src/com/oracle/graal/pointsto/meta/AnalysisUniverse.java

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2012, 2017, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2012, 2025, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -471,7 +471,7 @@ public AnalysisMethod[] lookup(JavaMethod[] inputs) {
                 }
             }
         }
-        return result.toArray(new AnalysisMethod[result.size()]);
+        return result.toArray(AnalysisMethod.EMPTY_ARRAY);
     }
 
     @Override

substratevm/src/com.oracle.svm.hosted/src/com/oracle/svm/hosted/annotation/SubstrateAnnotationExtractor.java

@@ -279,6 +279,9 @@ private AnnotationValue[][] getParameterAnnotationDataFromRoot(Executable rootEl
             ByteBuffer buf = ByteBuffer.wrap(rawParameterAnnotations);
             try {
                 int numParameters = buf.get() & 0xFF;
+                if (numParameters == 0) {
+                    return NO_PARAMETER_ANNOTATIONS;
+                }
                 AnnotationValue[][] parameterAnnotations = new AnnotationValue[numParameters][];
                 for (int i = 0; i < numParameters; i++) {
                     List<AnnotationValue> parameterAnnotationList = new ArrayList<>();

substratevm/src/com.oracle.svm.hosted/src/com/oracle/svm/hosted/code/RestrictHeapAccessCalleesImpl.java

@@ -114,7 +114,7 @@ public void aggregateMethods(Collection<AnalysisMethod> methods) {
         }
         MethodAggregator visitor = new MethodAggregator(aggregation, assertionErrorConstructorList);
         AnalysisMethodCalleeWalker walker = new AnalysisMethodCalleeWalker();
-        for (AnalysisMethod method : aggregation.keySet().toArray(new AnalysisMethod[0])) {
+        for (AnalysisMethod method : aggregation.keySet().toArray(AnalysisMethod.EMPTY_ARRAY)) {
             walker.walkMethod(method, visitor);
         }
         calleeToCallerMap = Collections.unmodifiableMap(aggregation);

substratevm/src/com.oracle.svm.hosted/src/com/oracle/svm/hosted/code/RuntimeMetadataEncoderImpl.java

@@ -720,7 +720,8 @@ public void addRecordComponentsLookupError(HostedType declaringClass, Throwable
     }
 
     private static HostedType[] getParameterTypes(HostedMethod method) {
-        HostedType[] parameterTypes = new HostedType[method.getSignature().getParameterCount(false)];
+        int len = method.getSignature().getParameterCount(false);
+        HostedType[] parameterTypes = len == 0 ? HostedType.EMPTY_ARRAY : new HostedType[len];
         for (int i = 0; i < parameterTypes.length; ++i) {
             parameterTypes[i] = method.getSignature().getParameterType(i);
         }
@@ -737,7 +738,7 @@ private static String[] getParameterTypeNames(HostedMethod method) {
 
     private static HostedType[] getExceptionTypes(MetaAccessProvider metaAccess, Executable reflectMethod) {
         Class<?>[] exceptionClasses = reflectMethod.getExceptionTypes();
-        HostedType[] exceptionTypes = new HostedType[exceptionClasses.length];
+        HostedType[] exceptionTypes = exceptionClasses.length == 0 ? HostedType.EMPTY_ARRAY : new HostedType[exceptionClasses.length];
         for (int i = 0; i < exceptionClasses.length; ++i) {
             exceptionTypes[i] = (HostedType) metaAccess.lookupJavaType(exceptionClasses[i]);
         }

substratevm/src/com.oracle.svm.hosted/src/com/oracle/svm/hosted/image/NativeImageHeapWriter.java

@@ -104,7 +104,7 @@ public NativeImageHeapWriter(NativeImageHeap heap, ImageHeapLayoutInfo heapLayou
     public long writeHeap(DebugContext debug, RelocatableBuffer buffer) {
         try (Indent perHeapIndent = debug.logAndIndent("NativeImageHeap.writeHeap:")) {
             for (ObjectInfo info : heap.getObjects()) {
-                assert !heap.isBlacklisted(info.getObject());
+                assert !heap.isBlacklisted(info.getObject()) : "Backlisted object: " + info.getObject();
                 if (info.getConstant().isWrittenInPreviousLayer()) {
                     /*
                      * Base layer constants already written in the base layer heap are only added to

substratevm/src/com.oracle.svm.hosted/src/com/oracle/svm/hosted/meta/HostedArrayClass.java

@@ -81,7 +81,7 @@ public int getArrayDimension() {
 
     @Override
     public HostedField[] getInstanceFields(boolean includeSuperclasses) {
-        return new HostedField[0];
+        return HostedField.EMPTY_ARRAY;
     }
 
     @Override

substratevm/src/com.oracle.svm.hosted/src/com/oracle/svm/hosted/meta/HostedField.java

@@ -43,6 +43,10 @@
  */
 public class HostedField extends HostedElement implements OriginalFieldProvider, SharedField, WrappedJavaField {
 
+    static final int LOC_UNMATERIALIZED_STATIC_CONSTANT = -10;
+
+    public static final HostedField[] EMPTY_ARRAY = new HostedField[0];
+
     public final AnalysisField wrapped;
 
     private final HostedType holder;
@@ -51,8 +55,6 @@ public class HostedField extends HostedElement implements OriginalFieldProvider,
     protected int location;
     private int installedLayerNum;
 
-    static final int LOC_UNMATERIALIZED_STATIC_CONSTANT = -10;
-
     public HostedField(AnalysisField wrapped, HostedType holder, HostedType type) {
         this.wrapped = wrapped;
         this.holder = holder;