[GR-69081] Remove isValueAvailable from SharedField

PullRequest: graal/21936

Author: teshull

substratevm/src/com.oracle.svm.core/src/com/oracle/svm/core/graal/nodes/SubstrateFieldLocationIdentity.java

@@ -24,10 +24,9 @@
  */
 package com.oracle.svm.core.graal.nodes;
 
-import jdk.graal.compiler.nodes.FieldLocationIdentity;
-
 import com.oracle.svm.core.meta.SharedField;
 
+import jdk.graal.compiler.nodes.FieldLocationIdentity;
 import jdk.vm.ci.meta.ResolvedJavaField;
 
 public class SubstrateFieldLocationIdentity extends FieldLocationIdentity {
@@ -42,6 +41,7 @@ public SubstrateFieldLocationIdentity(FieldLocationIdentity identity) {
 
     @Override
     public boolean isImmutable() {
-        return super.isImmutable() || (getField() instanceof SharedField sField && !sField.isWritten() && sField.isValueAvailable());
+        /* We can also treat a field as immutable if the analysis determines it is never written. */
+        return super.isImmutable() || (getField() instanceof SharedField sField && !sField.isWritten());
     }
 }

substratevm/src/com.oracle.svm.core/src/com/oracle/svm/core/meta/SharedField.java

@@ -59,12 +59,6 @@ public interface SharedField extends ResolvedJavaField {
 
     boolean isWritten();
 
-    /**
-     * Returns true if the field's value is available at the time of querying. For unknown fields
-     * this depends on the image build stage when the value is computed.
-     */
-    boolean isValueAvailable();
-
     JavaKind getStorageKind();
 
     /**

substratevm/src/com.oracle.svm.graal/src/com/oracle/svm/graal/hosted/runtimecompilation/GraalGraphObjectReplacer.java

@@ -520,7 +520,7 @@ public void updateSubstrateDataAfterCompilation(HostedUniverse hUniverse, Provid
                             ? providers.getConstantReflection().readFieldValue(hField, null)
                             : null;
             constantValue = SubstrateGraalUtils.hostedToRuntime(constantValue, providers.getConstantReflection());
-            sField.setSubstrateDataAfterCompilation(hField.getLocation(), hField.isAccessed(), hField.isWritten() || !hField.isValueAvailable(), constantValue);
+            sField.setSubstrateDataAfterCompilation(hField.getLocation(), hField.isAccessed(), hField.isWritten(), constantValue);
         }
 
         methods.forEach((aMethod, sMethod) -> {

substratevm/src/com.oracle.svm.graal/src/com/oracle/svm/graal/meta/SubstrateField.java

@@ -177,11 +177,6 @@ public boolean isSynthetic() {
         throw intentionallyUnimplemented(); // ExcludeFromJacocoGeneratedReport
     }
 
-    @Override
-    public boolean isValueAvailable() {
-        return true;
-    }
-
     @Override
     public int getInstalledLayerNum() {
         /*

substratevm/src/com.oracle.svm.hosted/src/com/oracle/svm/hosted/ameta/AnalysisConstantReflectionProvider.java

@@ -42,7 +42,6 @@
 import com.oracle.graal.pointsto.meta.AnalysisField;
 import com.oracle.graal.pointsto.meta.AnalysisType;
 import com.oracle.graal.pointsto.meta.AnalysisUniverse;
-import com.oracle.graal.pointsto.util.AnalysisError;
 import com.oracle.svm.core.classinitialization.TypeReachedProvider;
 import com.oracle.svm.core.hub.DynamicHub;
 import com.oracle.svm.core.util.VMError;
@@ -230,13 +229,19 @@ public JavaConstant readValue(AnalysisField field, JavaConstant receiver, boolea
         }
 
         if (field.preventConstantFolding()) {
+            /* Reading this value is prohibited. */
             return null;
         }
 
         if (receiver instanceof ImageHeapInstance imageHeapInstance && imageHeapInstance.isInBaseLayer() && imageHeapInstance.nullFieldValues()) {
             return null;
         }
 
+        if (!fieldValueInterceptionSupport.isValueAvailable(field)) {
+            /* Value is not yet available. */
+            return null;
+        }
+
         VMError.guarantee(receiver == null || receiver instanceof ImageHeapConstant, "Expected ImageHeapConstant, found: %s", receiver);
         JavaConstant value = null;
         if (returnSimulatedValues) {
@@ -260,7 +265,6 @@ public JavaConstant readValue(AnalysisField field, JavaConstant receiver, boolea
         }
         if (value == null && receiver instanceof ImageHeapConstant heapConstant) {
             heapConstant.ensureReaderInstalled();
-            AnalysisError.guarantee(fieldValueInterceptionSupport.isValueAvailable(field), "Value not yet available for %s", field);
             ImageHeapInstance heapObject = (ImageHeapInstance) receiver;
             value = heapObject.readFieldValue(field);
         }

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

@@ -303,10 +303,6 @@ public Object readInlinedField(HostedField field, JavaConstant receiver) {
         return hUniverse.getSnippetReflection().asObject(Object.class, constant);
     }
 
-    private JavaConstant readConstantField(HostedField field, JavaConstant receiver) {
-        return hConstantReflection.readFieldValue(field, receiver, true);
-    }
-
     private void addStaticFields() {
         addObject(StaticFieldsSupport.getCurrentLayerStaticObjectFields(), false, HeapInclusionReason.StaticObjectFields);
         addObject(StaticFieldsSupport.getCurrentLayerStaticPrimitiveFields(), false, HeapInclusionReason.StaticPrimitiveFields);
@@ -319,7 +315,7 @@ private void addStaticFields() {
             if (field.getWrapped().installableInLayer() && Modifier.isStatic(field.getModifiers()) && field.hasLocation() && field.getType().getStorageKind() == JavaKind.Object && field.isRead()) {
                 assert field.isWritten() || !field.isValueAvailable() || MaterializedConstantFields.singleton().contains(field.wrapped);
                 /* GR-56699 currently static fields cannot be ImageHeapRelocatableConstants. */
-                addConstant(readConstantField(field, null), false, field);
+                addConstant(hConstantReflection.readConstantField(field, null), false, field);
             }
         }
     }
@@ -600,7 +596,7 @@ private void addObjectToImageHeap(final JavaConstant constant, boolean immutable
                     if (field.isRead() && field.isValueAvailable() && !ignoredFields.contains(field)) {
                         if (field.getJavaKind() == JavaKind.Object) {
                             assert field.hasLocation();
-                            JavaConstant fieldValueConstant = hConstantReflection.readFieldValue(field, constant, true);
+                            JavaConstant fieldValueConstant = hConstantReflection.readConstantField(field, constant);
                             if (fieldValueConstant.getJavaKind() == JavaKind.Object) {
                                 if (spawnIsolates()) {
                                     fieldRelocatable = isRelocatableConstant(fieldValueConstant);

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

@@ -174,7 +174,7 @@ private void writeField(RelocatableBuffer buffer, ObjectInfo fields, HostedField
         int index = getIndexInBuffer(fields, field.getLocation());
         JavaConstant value;
         try {
-            value = heap.hConstantReflection.readFieldValue(field, receiver, true);
+            value = heap.hConstantReflection.readConstantField(field, receiver);
         } catch (AnalysisError.TypeNotFoundError ex) {
             throw NativeImageHeap.reportIllegalType(ex.getType(), info);
         }

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

@@ -58,7 +58,7 @@ public boolean isFinalField(ResolvedJavaField f, ConstantFieldTool<?> tool) {
     public static boolean isFinalField(HostedField field) {
         if (field.location == HostedField.LOC_UNMATERIALIZED_STATIC_CONSTANT) {
             return true;
-        } else if (!field.isWritten() && field.isValueAvailable()) {
+        } else if (!field.isWritten()) {
             return true;
         }
         return false;

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

@@ -26,6 +26,8 @@
 
 import static com.oracle.svm.core.util.VMError.shouldNotReachHereAtRuntime;
 
+import java.util.Objects;
+
 import org.graalvm.nativeimage.Platform;
 import org.graalvm.nativeimage.Platforms;
 
@@ -71,10 +73,15 @@ public JavaConstant asJavaClass(ResolvedJavaType type) {
 
     @Override
     public JavaConstant readFieldValue(ResolvedJavaField field, JavaConstant receiver) {
-        return readFieldValue(field, receiver, false);
+        return readFieldValueHelper(field, receiver, false);
+    }
+
+    /** Same as {@link #readFieldValue}, except that the field value must be available. */
+    public JavaConstant readConstantField(ResolvedJavaField field, JavaConstant receiver) {
+        return Objects.requireNonNull(readFieldValueHelper(field, receiver, true));
     }
 
-    public JavaConstant readFieldValue(ResolvedJavaField field, JavaConstant receiver, boolean readRelocatableValues) {
+    private JavaConstant readFieldValueHelper(ResolvedJavaField field, JavaConstant receiver, boolean readRelocatableValues) {
         var hField = (HostedField) field;
         assert checkHub(receiver) : "Receiver " + receiver + " of field " + hField + " read should not be java.lang.Class. Expecting to see DynamicHub here.";
         return super.readValue(hField.getWrapped(), receiver, true, readRelocatableValues);

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

@@ -144,7 +144,6 @@ public boolean isWritten() {
         return wrapped.isWritten();
     }
 
-    @Override
     public boolean isValueAvailable() {
         return FieldValueInterceptionSupport.singleton().isValueAvailable(wrapped);
     }