Ensure fields position is stable between layers.

Author: cstancu

substratevm/src/com.oracle.graal.pointsto/src/com/oracle/graal/pointsto/api/HostVM.java

@@ -313,10 +313,6 @@ public boolean platformSupported(AnnotatedElement element) {
         return true;
     }
 
-    public boolean sortFields() {
-        return false;
-    }
-
     public void clearInThread() {
     }
 

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

@@ -28,7 +28,6 @@
 import java.util.ArrayList;
 import java.util.Arrays;
 import java.util.Collection;
-import java.util.Comparator;
 import java.util.HashSet;
 import java.util.List;
 import java.util.Objects;
@@ -1197,22 +1196,8 @@ private ResolvedJavaField[] initializeInstanceFields(boolean includeSuperclasses
         return result;
     }
 
-    /**
-     * Sort fields by the field's name *and* type. Note that sorting by name is not enough as the
-     * class file format doesn't disallow duplicated names with differing types in the same class.
-     * Even though you cannot declare duplicated names in source code the class file can be
-     * manipulated such that two fields will have the same name.
-     */
-    static final Comparator<ResolvedJavaField> FIELD_COMPARATOR = Comparator.comparing(ResolvedJavaField::getName).thenComparing(f -> f.getType().toJavaName());
-
     private ResolvedJavaField[] convertFields(ResolvedJavaField[] originals, List<ResolvedJavaField> list, boolean listIncludesSuperClassesFields) {
-        ResolvedJavaField[] localOriginals = originals;
-        if (universe.hostVM.sortFields()) {
-            /* Clone the originals; it is a reference to the wrapped type's instanceFields array. */
-            localOriginals = originals.clone();
-            Arrays.sort(localOriginals, FIELD_COMPARATOR);
-        }
-        for (ResolvedJavaField original : localOriginals) {
+        for (ResolvedJavaField original : originals) {
             if (!original.isInternal() && universe.hostVM.platformSupported(original)) {
                 try {
                     AnalysisField aField = universe.lookup(original);

substratevm/src/com.oracle.svm.hosted/src/com/oracle/svm/hosted/SVMHost.java

@@ -1001,15 +1001,6 @@ private void initializeSharedLayerExcludedFields() {
         sharedLayerExcludedFields.add(lookupOriginalDeclaredField(NativeLibraries.class, "nativeLibraryLockMap"));
     }
 
-    @Override
-    public boolean sortFields() {
-        /*
-         * If building layered images sort the fields by kind and name to ensure stable order.
-         * Sorting fields in general may lead to some issues. (GR-62599)
-         */
-        return buildingImageLayer;
-    }
-
     /** If it's not one of the known builder types it must be an original VM type. */
     private static boolean isOriginalType(ResolvedJavaType type) {
         return !(type instanceof OriginalClassProvider);

substratevm/src/com.oracle.svm.hosted/src/com/oracle/svm/hosted/imagelayer/SVMImageLayerLoader.java

@@ -51,7 +51,6 @@
 import java.util.function.Supplier;
 import java.util.stream.IntStream;
 
-import com.oracle.svm.hosted.substitute.SubstitutionMethod;
 import org.graalvm.collections.EconomicMap;
 import org.graalvm.nativeimage.AnnotationAccess;
 import org.graalvm.nativeimage.ImageSingletons;
@@ -121,6 +120,7 @@
 import com.oracle.svm.hosted.meta.PatchedWordConstant;
 import com.oracle.svm.hosted.reflect.ReflectionFeature;
 import com.oracle.svm.hosted.reflect.serialize.SerializationFeature;
+import com.oracle.svm.hosted.substitute.SubstitutionMethod;
 import com.oracle.svm.hosted.util.IdentityHashCodeUtil;
 import com.oracle.svm.shaded.org.capnproto.PrimitiveList;
 import com.oracle.svm.shaded.org.capnproto.StructList;
@@ -1318,6 +1318,12 @@ public void initializeBaseLayerField(AnalysisField analysisField) {
         });
         registerFlag(fieldData.getIsFolded(), debug -> analysisField.registerAsFolded(PERSISTED));
         registerFlag(fieldData.getIsUnsafeAccessed(), debug -> analysisField.registerAsUnsafeAccessed(PERSISTED));
+
+        /*
+         * Inject the base layer position. If the position computed for this layer, either before
+         * this step or later, is different this will result in a failed guarantee.
+         */
+        analysisField.setPosition(fieldData.getPosition());
     }
 
     private PersistedAnalysisField.Reader getFieldData(AnalysisField analysisField) {