[GR-25050] Code refactoring for heap scanning.

PullRequest: graal/10756

Author: cstancu

substratevm/src/com.oracle.graal.pointsto/src/com/oracle/graal/pointsto/AnalysisObjectScanningObserver.java

@@ -24,6 +24,7 @@
  */
 package com.oracle.graal.pointsto;
 
+import com.oracle.graal.pointsto.ObjectScanner.ScanReason;
 import com.oracle.graal.pointsto.flow.ArrayElementsTypeFlow;
 import com.oracle.graal.pointsto.flow.FieldTypeFlow;
 import com.oracle.graal.pointsto.flow.context.object.AnalysisObject;
@@ -42,35 +43,37 @@ public AnalysisObjectScanningObserver(BigBang bb) {
     }
 
     @Override
-    public void forRelocatedPointerFieldValue(JavaConstant receiver, AnalysisField field, JavaConstant fieldValue) {
+    public boolean forRelocatedPointerFieldValue(JavaConstant receiver, AnalysisField field, JavaConstant fieldValue, ScanReason reason) {
         if (!field.isWritten()) {
-            field.registerAsWritten(null);
+            return field.registerAsWritten(null);
         }
+        return false;
     }
 
     @Override
-    public void forNullFieldValue(JavaConstant receiver, AnalysisField field) {
+    public boolean forNullFieldValue(JavaConstant receiver, AnalysisField field, ScanReason reason) {
         FieldTypeFlow fieldTypeFlow = getFieldTypeFlow(field, receiver);
         if (!fieldTypeFlow.getState().canBeNull()) {
             /* Signal that the field can contain null. */
-            fieldTypeFlow.addState(getAnalysis(), TypeState.forNull());
+            return fieldTypeFlow.addState(getAnalysis(), TypeState.forNull());
         }
+        return false;
     }
 
     @Override
-    public void forNonNullFieldValue(JavaConstant receiver, AnalysisField field, JavaConstant fieldValue) {
+    public boolean forNonNullFieldValue(JavaConstant receiver, AnalysisField field, JavaConstant fieldValue, ScanReason reason) {
         PointsToAnalysis analysis = getAnalysis();
         AnalysisType fieldType = analysis.getMetaAccess().lookupJavaType(analysis.getSnippetReflectionProvider().asObject(Object.class, fieldValue).getClass());
-        assert fieldType.isInstantiated() : fieldType;
 
         /* Add the constant value object to the field's type flow. */
         FieldTypeFlow fieldTypeFlow = getFieldTypeFlow(field, receiver);
         AnalysisObject constantObject = bb.analysisPolicy().createConstantObject(analysis, fieldValue, fieldType);
         if (!fieldTypeFlow.getState().containsObject(constantObject)) {
             /* Add the new constant to the field's flow state. */
             TypeState constantTypeState = TypeState.forNonNullObject(analysis, constantObject);
-            fieldTypeFlow.addState(analysis, constantTypeState);
+            return fieldTypeFlow.addState(analysis, constantTypeState);
         }
+        return false;
     }
 
     /**
@@ -94,25 +97,26 @@ private FieldTypeFlow getFieldTypeFlow(AnalysisField field, JavaConstant receive
     }
 
     @Override
-    public void forNullArrayElement(JavaConstant array, AnalysisType arrayType, int elementIndex) {
+    public boolean forNullArrayElement(JavaConstant array, AnalysisType arrayType, int elementIndex, ScanReason reason) {
         ArrayElementsTypeFlow arrayObjElementsFlow = getArrayElementsFlow(array, arrayType);
         if (!arrayObjElementsFlow.getState().canBeNull()) {
             /* Signal that the constant array can contain null. */
-            arrayObjElementsFlow.addState(getAnalysis(), TypeState.forNull());
+            return arrayObjElementsFlow.addState(getAnalysis(), TypeState.forNull());
         }
+        return false;
     }
 
     @Override
-    public void forNonNullArrayElement(JavaConstant array, AnalysisType arrayType, JavaConstant elementConstant, AnalysisType elementType, int elementIndex) {
-        assert elementType.isInstantiated() : elementType;
+    public boolean forNonNullArrayElement(JavaConstant array, AnalysisType arrayType, JavaConstant elementConstant, AnalysisType elementType, int elementIndex, ScanReason reason) {
         ArrayElementsTypeFlow arrayObjElementsFlow = getArrayElementsFlow(array, arrayType);
         PointsToAnalysis analysis = getAnalysis();
         AnalysisObject constantObject = bb.analysisPolicy().createConstantObject(analysis, elementConstant, elementType);
         if (!arrayObjElementsFlow.getState().containsObject(constantObject)) {
             /* Add the constant element to the constant's array type flow. */
             TypeState elementTypeState = TypeState.forNonNullObject(analysis, constantObject);
-            arrayObjElementsFlow.addState(analysis, elementTypeState);
+            return arrayObjElementsFlow.addState(analysis, elementTypeState);
         }
+        return false;
     }
 
     /**
@@ -125,7 +129,7 @@ private ArrayElementsTypeFlow getArrayElementsFlow(JavaConstant array, AnalysisT
     }
 
     @Override
-    public void forScannedConstant(JavaConstant value, ObjectScanner.ScanReason reason) {
+    public void forScannedConstant(JavaConstant value, ScanReason reason) {
         PointsToAnalysis analysis = getAnalysis();
         Object valueObj = analysis.getSnippetReflectionProvider().asObject(Object.class, value);
         AnalysisType type = bb.getMetaAccess().lookupJavaType(valueObj.getClass());