Introduce DuplicableImageSingletons.

Author: teshull

substratevm/src/com.oracle.svm.core.genscavenge/src/com/oracle/svm/core/genscavenge/PinnedObjectSupportImpl.java

@@ -24,18 +24,22 @@
  */
 package com.oracle.svm.core.genscavenge;
 
+import java.util.EnumSet;
+
 import org.graalvm.nativeimage.PinnedObject;
 import org.graalvm.nativeimage.Platform;
 import org.graalvm.nativeimage.Platforms;
 import org.graalvm.word.Pointer;
 
 import com.oracle.svm.core.Uninterruptible;
 import com.oracle.svm.core.heap.AbstractPinnedObjectSupport;
+import com.oracle.svm.core.layeredimagesingleton.InitialLayerOnlyImageSingleton;
+import com.oracle.svm.core.layeredimagesingleton.LayeredImageSingletonBuilderFlags;
 
 import jdk.graal.compiler.nodes.NamedLocationIdentity;
 
 /** Support for pinning objects to a memory address with {@link PinnedObject}. */
-public final class PinnedObjectSupportImpl extends AbstractPinnedObjectSupport {
+public final class PinnedObjectSupportImpl extends AbstractPinnedObjectSupport implements InitialLayerOnlyImageSingleton {
     @Platforms(Platform.HOSTED_ONLY.class)
     public PinnedObjectSupportImpl() {
     }
@@ -62,4 +66,14 @@ private static void modifyPinnedObjectCount(Object object, int delta) {
 
         assert oldValue < Integer.MAX_VALUE;
     }
+
+    @Override
+    public EnumSet<LayeredImageSingletonBuilderFlags> getImageBuilderFlags() {
+        return LayeredImageSingletonBuilderFlags.ALL_ACCESS;
+    }
+
+    @Override
+    public boolean accessibleInFutureLayers() {
+        return true;
+    }
 }

substratevm/src/com.oracle.svm.core.genscavenge/src/com/oracle/svm/core/genscavenge/graal/GenScavengeGCFeature.java

@@ -28,7 +28,6 @@
 import java.util.List;
 import java.util.Map;
 
-import com.oracle.svm.core.jdk.SystemPropertiesSupport;
 import org.graalvm.nativeimage.ImageSingletons;
 import org.graalvm.nativeimage.hosted.Feature;
 import org.graalvm.nativeimage.impl.PinnedObjectSupport;
@@ -60,7 +59,9 @@
 import com.oracle.svm.core.heap.BarrierSetProvider;
 import com.oracle.svm.core.heap.Heap;
 import com.oracle.svm.core.image.ImageHeapLayouter;
+import com.oracle.svm.core.imagelayer.ImageLayerBuildingSupport;
 import com.oracle.svm.core.jdk.RuntimeSupportFeature;
+import com.oracle.svm.core.jdk.SystemPropertiesSupport;
 import com.oracle.svm.core.jvmstat.PerfDataFeature;
 import com.oracle.svm.core.jvmstat.PerfDataHolder;
 import com.oracle.svm.core.jvmstat.PerfManager;
@@ -100,7 +101,9 @@ public void duringSetup(DuringSetupAccess access) {
         ImageSingletons.add(Heap.class, new HeapImpl());
         ImageSingletons.add(ImageHeapInfo.class, new ImageHeapInfo());
         ImageSingletons.add(GCAllocationSupport.class, new GenScavengeAllocationSupport());
-        ImageSingletons.add(PinnedObjectSupport.class, new PinnedObjectSupportImpl());
+        if (ImageLayerBuildingSupport.firstImageBuild()) {
+            ImageSingletons.add(PinnedObjectSupport.class, new PinnedObjectSupportImpl());
+        }
 
         if (ImageSingletons.contains(PerfManager.class)) {
             ImageSingletons.lookup(PerfManager.class).register(createPerfData());

substratevm/src/com.oracle.svm.core.posix/src/com/oracle/svm/core/posix/PosixLogHandler.java

@@ -25,27 +25,33 @@
 package com.oracle.svm.core.posix;
 
 import java.io.FileDescriptor;
+import java.util.EnumSet;
 
+import com.oracle.svm.core.imagelayer.ImageLayerBuildingSupport;
 import org.graalvm.nativeimage.LogHandler;
 import org.graalvm.nativeimage.c.type.CCharPointer;
 import org.graalvm.word.UnsignedWord;
 
 import com.oracle.svm.core.SubstrateDiagnostics;
+import com.oracle.svm.core.feature.AutomaticallyRegisteredFeature;
 import com.oracle.svm.core.feature.InternalFeature;
 import com.oracle.svm.core.headers.LibC;
+import com.oracle.svm.core.layeredimagesingleton.InitialLayerOnlyImageSingleton;
+import com.oracle.svm.core.layeredimagesingleton.LayeredImageSingletonBuilderFlags;
 import com.oracle.svm.core.log.Log;
 import com.oracle.svm.core.thread.VMThreads;
-import com.oracle.svm.core.feature.AutomaticallyRegisteredFeature;
 
 @AutomaticallyRegisteredFeature
 class PosixLogHandlerFeature implements InternalFeature {
     @Override
     public void beforeAnalysis(BeforeAnalysisAccess access) {
-        Log.finalizeDefaultLogHandler(new PosixLogHandler());
+        if (ImageLayerBuildingSupport.firstImageBuild()) {
+            Log.finalizeDefaultLogHandler(new PosixLogHandler());
+        }
     }
 }
 
-public class PosixLogHandler implements LogHandler {
+public class PosixLogHandler implements LogHandler, InitialLayerOnlyImageSingleton {
 
     @Override
     public void log(CCharPointer bytes, UnsignedWord length) {
@@ -88,4 +94,14 @@ public void fatalError() {
     private static FileDescriptor getOutputFile() {
         return FileDescriptor.err;
     }
+
+    @Override
+    public EnumSet<LayeredImageSingletonBuilderFlags> getImageBuilderFlags() {
+        return LayeredImageSingletonBuilderFlags.RUNTIME_ACCESS_ONLY;
+    }
+
+    @Override
+    public boolean accessibleInFutureLayers() {
+        return true;
+    }
 }

substratevm/src/com.oracle.svm.core.posix/src/com/oracle/svm/core/posix/linux/LinuxPhysicalMemorySupportImpl.java

@@ -31,7 +31,6 @@
 import java.util.ArrayList;
 import java.util.List;
 
-import jdk.graal.compiler.word.Word;
 import org.graalvm.nativeimage.ImageSingletons;
 import org.graalvm.word.UnsignedWord;
 
@@ -40,9 +39,12 @@
 import com.oracle.svm.core.feature.InternalFeature;
 import com.oracle.svm.core.heap.PhysicalMemory;
 import com.oracle.svm.core.heap.PhysicalMemory.PhysicalMemorySupport;
+import com.oracle.svm.core.imagelayer.ImageLayerBuildingSupport;
 import com.oracle.svm.core.posix.headers.Unistd;
 import com.oracle.svm.core.util.VMError;
 
+import jdk.graal.compiler.word.Word;
+
 public class LinuxPhysicalMemorySupportImpl implements PhysicalMemorySupport {
 
     private static final long K = 1024;
@@ -121,7 +123,7 @@ private static long parseFirstNumber(String str) {
 class LinuxPhysicalMemorySupportFeature implements InternalFeature {
     @Override
     public void beforeAnalysis(BeforeAnalysisAccess access) {
-        if (!ImageSingletons.contains(PhysicalMemorySupport.class)) {
+        if (ImageLayerBuildingSupport.firstImageBuild() && !ImageSingletons.contains(PhysicalMemorySupport.class)) {
             ImageSingletons.add(PhysicalMemorySupport.class, new LinuxPhysicalMemorySupportImpl());
         }
     }

substratevm/src/com.oracle.svm.core.posix/src/com/oracle/svm/core/posix/linux/LinuxProcessPropertiesSupport.java

@@ -24,17 +24,31 @@
  */
 package com.oracle.svm.core.posix.linux;
 
+import java.util.EnumSet;
+
 import org.graalvm.nativeimage.impl.ProcessPropertiesSupport;
 
-import com.oracle.svm.core.posix.PosixProcessPropertiesSupport;
 import com.oracle.svm.core.feature.AutomaticallyRegisteredImageSingleton;
+import com.oracle.svm.core.layeredimagesingleton.InitialLayerOnlyImageSingleton;
+import com.oracle.svm.core.layeredimagesingleton.LayeredImageSingletonBuilderFlags;
+import com.oracle.svm.core.posix.PosixProcessPropertiesSupport;
 
 @AutomaticallyRegisteredImageSingleton(ProcessPropertiesSupport.class)
-public class LinuxProcessPropertiesSupport extends PosixProcessPropertiesSupport {
+public class LinuxProcessPropertiesSupport extends PosixProcessPropertiesSupport implements InitialLayerOnlyImageSingleton {
 
     @Override
     public String getExecutableName() {
         final String exefileString = "/proc/self/exe";
         return realpath(exefileString);
     }
+
+    @Override
+    public EnumSet<LayeredImageSingletonBuilderFlags> getImageBuilderFlags() {
+        return LayeredImageSingletonBuilderFlags.RUNTIME_ACCESS_ONLY;
+    }
+
+    @Override
+    public boolean accessibleInFutureLayers() {
+        return true;
+    }
 }

substratevm/src/com.oracle.svm.core/src/com/oracle/svm/core/c/CTypeConversionSupportImpl.java

@@ -28,8 +28,8 @@
 import java.nio.charset.Charset;
 import java.nio.charset.StandardCharsets;
 import java.util.Arrays;
+import java.util.EnumSet;
 
-import jdk.graal.compiler.word.Word;
 import org.graalvm.nativeimage.ImageSingletons;
 import org.graalvm.nativeimage.c.type.CCharPointer;
 import org.graalvm.nativeimage.c.type.CCharPointerPointer;
@@ -45,9 +45,13 @@
 import com.oracle.svm.core.feature.AutomaticallyRegisteredImageSingleton;
 import com.oracle.svm.core.handles.PrimitiveArrayView;
 import com.oracle.svm.core.jdk.DirectByteBufferUtil;
+import com.oracle.svm.core.layeredimagesingleton.InitialLayerOnlyImageSingleton;
+import com.oracle.svm.core.layeredimagesingleton.LayeredImageSingletonBuilderFlags;
+
+import jdk.graal.compiler.word.Word;
 
 @AutomaticallyRegisteredImageSingleton(CTypeConversionSupport.class)
-class CTypeConversionSupportImpl implements CTypeConversionSupport {
+class CTypeConversionSupportImpl implements CTypeConversionSupport, InitialLayerOnlyImageSingleton {
 
     static final CCharPointerHolder NULL_HOLDER = new CCharPointerHolder() {
         @Override
@@ -189,6 +193,16 @@ public ByteBuffer asByteBuffer(PointerBase address, int size) {
         ByteBuffer byteBuffer = DirectByteBufferUtil.allocate(address.rawValue(), size);
         return byteBuffer.order(ConfigurationValues.getTarget().arch.getByteOrder());
     }
+
+    @Override
+    public EnumSet<LayeredImageSingletonBuilderFlags> getImageBuilderFlags() {
+        return LayeredImageSingletonBuilderFlags.RUNTIME_ACCESS_ONLY;
+    }
+
+    @Override
+    public boolean accessibleInFutureLayers() {
+        return true;
+    }
 }
 
 final class CCharPointerHolderImpl implements CCharPointerHolder {

substratevm/src/com.oracle.svm.core/src/com/oracle/svm/core/c/function/IsolateSupportImpl.java

@@ -24,9 +24,9 @@
  */
 package com.oracle.svm.core.c.function;
 
+import java.util.EnumSet;
 import java.util.List;
 
-import jdk.graal.compiler.word.Word;
 import org.graalvm.nativeimage.Isolate;
 import org.graalvm.nativeimage.IsolateThread;
 import org.graalvm.nativeimage.Isolates.CreateIsolateParameters;
@@ -41,14 +41,18 @@
 import com.oracle.svm.core.c.function.CEntryPointNativeFunctions.IsolateThreadPointer;
 import com.oracle.svm.core.feature.AutomaticallyRegisteredImageSingleton;
 import com.oracle.svm.core.graal.stackvalue.UnsafeStackValue;
+import com.oracle.svm.core.layeredimagesingleton.InitialLayerOnlyImageSingleton;
+import com.oracle.svm.core.layeredimagesingleton.LayeredImageSingletonBuilderFlags;
 import com.oracle.svm.core.memory.NativeMemory;
 import com.oracle.svm.core.nmt.NmtCategory;
 import com.oracle.svm.core.option.SubstrateOptionsParser;
 import com.oracle.svm.core.os.MemoryProtectionProvider;
 import com.oracle.svm.core.os.MemoryProtectionProvider.UnsupportedDomainException;
 
+import jdk.graal.compiler.word.Word;
+
 @AutomaticallyRegisteredImageSingleton(IsolateSupport.class)
-public final class IsolateSupportImpl implements IsolateSupport {
+public final class IsolateSupportImpl implements IsolateSupport, InitialLayerOnlyImageSingleton {
     private static final String ISOLATES_DISABLED_MESSAGE = "Spawning of multiple isolates is disabled, use " +
                     SubstrateOptionsParser.commandArgument(SubstrateOptions.SpawnIsolates, "+") + " option.";
     private static final String PROTECTION_DOMAIN_UNSUPPORTED_MESSAGE = "Protection domains are unavailable";
@@ -167,4 +171,14 @@ private static void throwOnError(int code) {
             throw new IsolateException(message);
         }
     }
+
+    @Override
+    public EnumSet<LayeredImageSingletonBuilderFlags> getImageBuilderFlags() {
+        return LayeredImageSingletonBuilderFlags.RUNTIME_ACCESS_ONLY;
+    }
+
+    @Override
+    public boolean accessibleInFutureLayers() {
+        return true;
+    }
 }

substratevm/src/com.oracle.svm.core/src/com/oracle/svm/core/handles/ObjectHandlesSupportImpl.java

@@ -24,13 +24,17 @@
  */
 package com.oracle.svm.core.handles;
 
+import java.util.EnumSet;
+
 import org.graalvm.nativeimage.ObjectHandles;
 import org.graalvm.nativeimage.impl.ObjectHandlesSupport;
 
 import com.oracle.svm.core.feature.AutomaticallyRegisteredImageSingleton;
+import com.oracle.svm.core.layeredimagesingleton.InitialLayerOnlyImageSingleton;
+import com.oracle.svm.core.layeredimagesingleton.LayeredImageSingletonBuilderFlags;
 
 @AutomaticallyRegisteredImageSingleton(ObjectHandlesSupport.class)
-class ObjectHandlesSupportImpl implements ObjectHandlesSupport {
+class ObjectHandlesSupportImpl implements ObjectHandlesSupport, InitialLayerOnlyImageSingleton {
     final ObjectHandlesImpl globalHandles = new ObjectHandlesImpl();
 
     @Override
@@ -42,4 +46,19 @@ public ObjectHandles getGlobalHandles() {
     public ObjectHandles createHandles() {
         return new ObjectHandlesImpl();
     }
+
+    @Override
+    public EnumSet<LayeredImageSingletonBuilderFlags> getImageBuilderFlags() {
+        /*
+         * In some cases object instances are accessed during code initialized at buildtime.
+         * However, when this is done, one must be very careful to ensure analysis sees all changes
+         * made to these objects.
+         */
+        return LayeredImageSingletonBuilderFlags.ALL_ACCESS;
+    }
+
+    @Override
+    public boolean accessibleInFutureLayers() {
+        return true;
+    }
 }

substratevm/src/com.oracle.svm.core/src/com/oracle/svm/core/heap/PhysicalMemory.java

@@ -25,8 +25,8 @@
 package com.oracle.svm.core.heap;
 
 import java.lang.management.ManagementFactory;
+import java.util.EnumSet;
 
-import jdk.graal.compiler.word.Word;
 import org.graalvm.nativeimage.ImageSingletons;
 import org.graalvm.nativeimage.Platform;
 import org.graalvm.word.UnsignedWord;
@@ -36,18 +36,21 @@
 import com.oracle.svm.core.Uninterruptible;
 import com.oracle.svm.core.container.Container;
 import com.oracle.svm.core.container.OperatingSystem;
-import com.oracle.svm.core.layeredimagesingleton.RuntimeOnlyImageSingleton;
+import com.oracle.svm.core.layeredimagesingleton.InitialLayerOnlyImageSingleton;
+import com.oracle.svm.core.layeredimagesingleton.LayeredImageSingletonBuilderFlags;
 import com.oracle.svm.core.util.UnsignedUtils;
 import com.oracle.svm.core.util.VMError;
 import com.sun.management.OperatingSystemMXBean;
 
+import jdk.graal.compiler.word.Word;
+
 /**
  * Contains static methods to get configuration of physical memory.
  */
 public class PhysicalMemory {
 
     /** Implemented by operating-system specific code. */
-    public interface PhysicalMemorySupport extends RuntimeOnlyImageSingleton {
+    public interface PhysicalMemorySupport extends InitialLayerOnlyImageSingleton {
         /** Get the size of physical memory from the OS. */
         UnsignedWord size();
 
@@ -62,6 +65,11 @@ public interface PhysicalMemorySupport extends RuntimeOnlyImageSingleton {
         default long usedSize() {
             return -1L;
         }
+
+        @Override
+        default EnumSet<LayeredImageSingletonBuilderFlags> getImageBuilderFlags() {
+            return LayeredImageSingletonBuilderFlags.RUNTIME_ACCESS_ONLY;
+        }
     }
 
     private static final UnsignedWord UNSET_SENTINEL = UnsignedUtils.MAX_VALUE;

substratevm/src/com.oracle.svm.core/src/com/oracle/svm/core/layeredimagesingleton/RuntimeOnlyImageSingleton.java renamed to substratevm/src/com.oracle.svm.core/src/com/oracle/svm/core/layeredimagesingleton/DuplicableImageSingleton.java

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2024, 2024, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2025, 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
@@ -24,17 +24,19 @@
  */
 package com.oracle.svm.core.layeredimagesingleton;
 
-import java.util.EnumSet;
-
-public interface RuntimeOnlyImageSingleton extends LayeredImageSingleton {
-
-    @Override
-    default EnumSet<LayeredImageSingletonBuilderFlags> getImageBuilderFlags() {
-        return LayeredImageSingletonBuilderFlags.RUNTIME_ACCESS_ONLY;
-    }
-
-    @Override
-    default PersistFlags preparePersist(ImageSingletonWriter writer) {
-        return PersistFlags.NOTHING;
-    }
+/**
+ * A Duplicable ImageSingleton can have multiple instances of the object installed in the Image Heap
+ * (at most one per a layer). The specific instance referred to from a given piece of code is
+ * dependent on the layer in which the code was installed in.
+ *
+ * It is expected that either the installed objects (1) have no instance fields or (2) have instance
+ * fields which have been made layer-aware through other means (e.g. using a layered ImageHeapMap).
+ *
+ * Note this is a temporary marker and eventually all instances of {@link DuplicableImageSingleton}s
+ * should be removed. This marker should only be used when there is not a correctness issue with
+ * installing multiple instances of the singleton. Instead, the marker indicates there is merely a
+ * performance/memory overhead due to having multiple copies of this singleton installed (via
+ * different layers) within the image heap.
+ */
+public interface DuplicableImageSingleton extends LayeredImageSingleton {
 }