Remove concept of frozen unsafe accessed fields

Author: Christian Wimmer

substratevm/src/com.oracle.graal.pointsto.standalone/src/com/oracle/graal/pointsto/standalone/features/StandaloneAnalysisFeatureImpl.java

@@ -221,15 +221,6 @@ public boolean registerAsUnsafeAccessed(AnalysisField aField, Object reason) {
             return false;
         }
 
-        public void registerAsFrozenUnsafeAccessed(Field field) {
-            registerAsFrozenUnsafeAccessed(getMetaAccess().lookupJavaField(field));
-        }
-
-        public void registerAsFrozenUnsafeAccessed(AnalysisField aField) {
-            aField.registerAsFrozenUnsafeAccessed();
-            registerAsUnsafeAccessed(aField, "registered from standalone feature");
-        }
-
         public void registerAsUnsafeAccessed(Field field, Object reason) {
             registerAsUnsafeAccessed(getMetaAccess().lookupJavaField(field), reason);
         }

substratevm/src/com.oracle.graal.pointsto/src/com/oracle/graal/pointsto/flow/FieldTypeFlow.java

@@ -55,17 +55,17 @@ private static TypeState initialFieldState(AnalysisField field) {
     }
 
     /** The holder of the field flow (null for static fields). */
-    private AnalysisObject object;
+    private final AnalysisObject object;
 
     /** A filter flow used for unsafe writes. */
     private volatile FieldFilterTypeFlow filterFlow;
 
     public FieldTypeFlow(AnalysisField field, AnalysisType type) {
-        super(field, filterUncheckedInterface(type), initialFieldState(field));
+        this(field, type, null);
     }
 
     public FieldTypeFlow(AnalysisField field, AnalysisType type, AnalysisObject object) {
-        this(field, type);
+        super(field, filterUncheckedInterface(type), initialFieldState(field));
         this.object = object;
     }
 

substratevm/src/com.oracle.graal.pointsto/src/com/oracle/graal/pointsto/flow/FrozenFieldFilterTypeFlow.java

@@ -213,20 +213,14 @@ public void forceUpdate(PointsToAnalysis bb) {
              * can write to any of the static fields marked for unsafe access.
              */
             for (AnalysisField field : bb.getUniverse().getUnsafeAccessedStaticFields()) {
-                this.addUse(bb, field.getStaticFieldFlow().filterFlow(bb));
+                addUse(bb, field.getStaticFieldFlow().filterFlow(bb));
             }
         }
 
         void handleUnsafeAccessedFields(PointsToAnalysis bb, Collection<AnalysisField> unsafeAccessedFields, AnalysisObject object) {
             for (AnalysisField field : unsafeAccessedFields) {
                 /* Write through the field filter flow. */
-                if (field.hasUnsafeFrozenTypeState()) {
-                    UnsafeWriteSinkTypeFlow unsafeWriteSink = object.getUnsafeWriteSinkFrozenFilterFlow(bb, objectFlow, source, field);
-                    this.addUse(bb, unsafeWriteSink);
-                } else {
-                    FieldFilterTypeFlow fieldFilterFlow = object.getInstanceFieldFilterFlow(bb, objectFlow, source, field);
-                    this.addUse(bb, fieldFilterFlow);
-                }
+                addUse(bb, object.getInstanceFieldFilterFlow(bb, objectFlow, source, field));
             }
         }
     }

substratevm/src/com.oracle.graal.pointsto/src/com/oracle/graal/pointsto/flow/OffsetStoreTypeFlow.java

@@ -35,7 +35,6 @@
 import com.oracle.graal.pointsto.flow.FieldFilterTypeFlow;
 import com.oracle.graal.pointsto.flow.FieldTypeFlow;
 import com.oracle.graal.pointsto.flow.TypeFlow;
-import com.oracle.graal.pointsto.flow.UnsafeWriteSinkTypeFlow;
 import com.oracle.graal.pointsto.meta.AnalysisField;
 import com.oracle.graal.pointsto.meta.AnalysisType;
 import com.oracle.graal.pointsto.meta.AnalysisUniverse;
@@ -198,21 +197,15 @@ public ArrayElementsTypeFlow getArrayElementsFlow(PointsToAnalysis bb, boolean i
         return isStore ? arrayElementsTypeStore.writeFlow() : arrayElementsTypeStore.readFlow();
     }
 
-    /** Returns the filter field flow corresponding to an unsafe accessed filed. */
+    /** Returns the filter field flow corresponding to an unsafe accessed field. */
     public FieldFilterTypeFlow getInstanceFieldFilterFlow(PointsToAnalysis bb, TypeFlow<?> objectFlow, BytecodePosition context, AnalysisField field) {
         assert !Modifier.isStatic(field.getModifiers()) && field.isUnsafeAccessed() : field;
 
         FieldTypeStore fieldTypeStore = getInstanceFieldTypeStore(bb, objectFlow, context, field);
         return fieldTypeStore.writeFlow().filterFlow(bb);
     }
 
-    public UnsafeWriteSinkTypeFlow getUnsafeWriteSinkFrozenFilterFlow(PointsToAnalysis bb, TypeFlow<?> objectFlow, BytecodePosition context, AnalysisField field) {
-        assert !Modifier.isStatic(field.getModifiers()) && field.hasUnsafeFrozenTypeState() : field;
-        FieldTypeStore fieldTypeStore = getInstanceFieldTypeStore(bb, objectFlow, context, field);
-        return fieldTypeStore.unsafeWriteSinkFlow(bb);
-    }
-
-    /** Returns the instance field flow corresponding to a filed of the object's type. */
+    /** Returns the instance field flow corresponding to a field of the object's type. */
     public FieldTypeFlow getInstanceFieldFlow(PointsToAnalysis bb, AnalysisField field, boolean isStore) {
         return getInstanceFieldFlow(bb, null, null, field, isStore);
     }

substratevm/src/com.oracle.graal.pointsto/src/com/oracle/graal/pointsto/flow/context/object/AnalysisObject.java

@@ -29,7 +29,6 @@
 import java.util.List;
 import java.util.concurrent.ConcurrentHashMap;
 import java.util.concurrent.ConcurrentMap;
-import java.util.concurrent.atomic.AtomicIntegerFieldUpdater;
 import java.util.concurrent.atomic.AtomicReferenceFieldUpdater;
 
 import com.oracle.graal.pointsto.api.HostVM;
@@ -68,9 +67,6 @@ public abstract class AnalysisField extends AnalysisElement implements WrappedJa
     private static final AtomicReferenceFieldUpdater<AnalysisField, Object> isUnsafeAccessedUpdater = AtomicReferenceFieldUpdater
                     .newUpdater(AnalysisField.class, Object.class, "isUnsafeAccessed");
 
-    private static final AtomicIntegerFieldUpdater<AnalysisField> unsafeFrozenTypeStateUpdater = AtomicIntegerFieldUpdater
-                    .newUpdater(AnalysisField.class, "unsafeFrozenTypeState");
-
     private final int id;
     /** Marks a field loaded from a base layer. */
     private final boolean isInBaseLayer;
@@ -94,12 +90,7 @@ public abstract class AnalysisField extends AnalysisElement implements WrappedJa
     @SuppressWarnings("unused") private volatile Object isAccessed;
     @SuppressWarnings("unused") private volatile Object isWritten;
     @SuppressWarnings("unused") private volatile Object isFolded;
-
-    private boolean isJNIAccessed;
-
     @SuppressWarnings("unused") private volatile Object isUnsafeAccessed;
-    @SuppressWarnings("unused") private volatile int unsafeFrozenTypeState;
-    @SuppressWarnings("unused") private volatile Object observers;
 
     /**
      * By default all instance fields are null before are initialized. It can be specified by
@@ -110,8 +101,6 @@ public abstract class AnalysisField extends AnalysisElement implements WrappedJa
     private ConcurrentMap<Object, Boolean> readBy;
     private ConcurrentMap<Object, Boolean> writtenBy;
 
-    protected TypeState instanceFieldTypeState;
-
     /** Field's position in the list of declaring type's fields, including inherited fields. */
     protected int position;
 
@@ -254,7 +243,6 @@ public void cleanupAfterAnalysis() {
         initialInstanceFieldFlow = null;
         readBy = null;
         writtenBy = null;
-        instanceFieldTypeState = null;
     }
 
     public boolean registerAsAccessed(Object reason) {
@@ -361,22 +349,6 @@ public boolean isUnsafeAccessed() {
         return AtomicUtils.isSet(this, isUnsafeAccessedUpdater);
     }
 
-    public void registerAsJNIAccessed() {
-        isJNIAccessed = true;
-    }
-
-    public boolean isJNIAccessed() {
-        return isJNIAccessed;
-    }
-
-    public void registerAsFrozenUnsafeAccessed() {
-        unsafeFrozenTypeStateUpdater.set(this, 1);
-    }
-
-    public boolean hasUnsafeFrozenTypeState() {
-        return AtomicUtils.isSet(this, unsafeFrozenTypeStateUpdater);
-    }
-
     public Object getReadBy() {
         return isReadUpdater.get(this);
     }

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

@@ -57,7 +57,6 @@
 import com.oracle.graal.pointsto.flow.FilterTypeFlow;
 import com.oracle.graal.pointsto.flow.FormalParamTypeFlow;
 import com.oracle.graal.pointsto.flow.FormalReturnTypeFlow;
-import com.oracle.graal.pointsto.flow.FrozenFieldFilterTypeFlow;
 import com.oracle.graal.pointsto.flow.InvokeTypeFlow;
 import com.oracle.graal.pointsto.flow.LoadFieldTypeFlow.LoadInstanceFieldTypeFlow;
 import com.oracle.graal.pointsto.flow.LoadFieldTypeFlow.LoadStaticFieldTypeFlow;
@@ -485,9 +484,6 @@ private static String asString(TypeFlow<?> flow) {
         } else if (flow instanceof FieldFilterTypeFlow) {
             FieldFilterTypeFlow filter = (FieldFilterTypeFlow) flow;
             return "FieldFilter(" + formatField(filter.getSource()) + ")";
-        } else if (flow instanceof FrozenFieldFilterTypeFlow) {
-            FrozenFieldFilterTypeFlow filter = (FrozenFieldFilterTypeFlow) flow;
-            return "FrozenFieldFilter(" + formatField(filter.getSource()) + ")";
         } else if (flow instanceof NewInstanceTypeFlow) {
             return "NewInstance(" + flow.getDeclaredType().toJavaName(false) + ")@" + formatSource(flow);
         } else if (flow instanceof DynamicNewInstanceTypeFlow) {

substratevm/src/com.oracle.graal.pointsto/src/com/oracle/graal/pointsto/typestate/PointsToStats.java

@@ -24,12 +24,8 @@
  */
 package com.oracle.graal.pointsto.typestore;
 
-import java.util.concurrent.atomic.AtomicReferenceFieldUpdater;
-
 import com.oracle.graal.pointsto.PointsToAnalysis;
 import com.oracle.graal.pointsto.flow.FieldTypeFlow;
-import com.oracle.graal.pointsto.flow.FrozenFieldFilterTypeFlow;
-import com.oracle.graal.pointsto.flow.UnsafeWriteSinkTypeFlow;
 import com.oracle.graal.pointsto.flow.context.object.AnalysisObject;
 import com.oracle.graal.pointsto.meta.AnalysisField;
 
@@ -38,18 +34,9 @@
  */
 public abstract class FieldTypeStore {
 
-    private static final AtomicReferenceFieldUpdater<FieldTypeStore, FrozenFieldFilterTypeFlow> FROZEN_FILTER_FLOW_UPDATER = AtomicReferenceFieldUpdater.newUpdater(FieldTypeStore.class,
-                    FrozenFieldFilterTypeFlow.class, "frozenFilterFlow");
-    private static final AtomicReferenceFieldUpdater<FieldTypeStore, UnsafeWriteSinkTypeFlow> UNSAFE_WRITE_SINK_FLOW_UPDATER = AtomicReferenceFieldUpdater.newUpdater(FieldTypeStore.class,
-                    UnsafeWriteSinkTypeFlow.class, "unsafeWriteSinkFlow");
-
     /** The holder of the field flow. */
     protected final AnalysisObject object;
     protected final AnalysisField field;
-    /** A filter flow used for unsafe writes on frozen type state. */
-    private volatile FrozenFieldFilterTypeFlow frozenFilterFlow;
-    /** A sink used for unsafe writes on frozen type state. */
-    private volatile UnsafeWriteSinkTypeFlow unsafeWriteSinkFlow;
 
     protected FieldTypeStore(AnalysisField field, AnalysisObject object) {
         this.field = field;
@@ -71,22 +58,4 @@ public AnalysisField field() {
     /** Overridden for field type stores that need lazy initialization. */
     public void init(@SuppressWarnings("unused") PointsToAnalysis bb) {
     }
-
-    public UnsafeWriteSinkTypeFlow unsafeWriteSinkFlow(PointsToAnalysis bb) {
-        assert field.hasUnsafeFrozenTypeState() : "Unsafe write sink flow requested for non unsafe accessed frozen field.";
-        // first we create the unsafe write sink
-        if (unsafeWriteSinkFlow == null) {
-            UNSAFE_WRITE_SINK_FLOW_UPDATER.compareAndSet(this, null, new UnsafeWriteSinkTypeFlow(bb, field));
-        }
-        // then we build the filter for it.
-        if (frozenFilterFlow == null) {
-            if (FROZEN_FILTER_FLOW_UPDATER.compareAndSet(this, null, new FrozenFieldFilterTypeFlow(bb, field, unsafeWriteSinkFlow))) {
-                frozenFilterFlow.addUse(bb, writeFlow());
-                unsafeWriteSinkFlow.addUse(bb, frozenFilterFlow);
-            }
-        }
-
-        return unsafeWriteSinkFlow;
-    }
-
 }

substratevm/src/com.oracle.graal.pointsto/src/com/oracle/graal/pointsto/typestore/FieldTypeStore.java

@@ -418,15 +418,6 @@ public boolean registerAsUnsafeAccessed(AnalysisField aField, Object reason) {
             return aField.registerAsUnsafeAccessed(reason);
         }
 
-        public void registerAsFrozenUnsafeAccessed(Field field, Object reason) {
-            registerAsFrozenUnsafeAccessed(getMetaAccess().lookupJavaField(field), reason);
-        }
-
-        public void registerAsFrozenUnsafeAccessed(AnalysisField aField, Object reason) {
-            aField.registerAsFrozenUnsafeAccessed();
-            registerAsUnsafeAccessed(aField, reason);
-        }
-
         public void registerAsRoot(Executable method, boolean invokeSpecial, String reason, MultiMethod.MultiMethodKey... otherRoots) {
             bb.addRootMethod(method, invokeSpecial, reason, otherRoots);
         }

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

@@ -497,7 +497,6 @@ private static void addField(Field reflField, boolean writable, DuringAnalysisAc
         JNIAccessibleClass jniClass = addClass(reflField.getDeclaringClass(), access);
         AnalysisField field = access.getMetaAccess().lookupJavaField(reflField);
         jniClass.addFieldIfAbsent(field.getName(), name -> new JNIAccessibleField(jniClass, field.getJavaKind(), field.getModifiers()));
-        field.registerAsJNIAccessed();
         field.registerAsRead("it is registered for as JNI accessed");
         if (writable) {
             field.registerAsWritten("it is registered as JNI writable");