[GR-47662] [GR-47506] Fix race on getAllCallees and typeflow creation.

PullRequest: graal/15142

Author: teshull

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

@@ -117,6 +117,11 @@ public Collection<AnalysisMethod> getAllCallees() {
         return ConcurrentLightHashSet.getElements(this, CALLEES_UPDATER);
     }
 
+    @Override
+    public final Collection<AnalysisMethod> getAllComputedCallees() {
+        return getAllCallees();
+    }
+
     @Override
     public String toString() {
         return "VirtualInvoke<" + targetMethod.format("%h.%n") + ">" + ":" + getState();

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

@@ -74,13 +74,24 @@ public final boolean isDirectInvoke() {
 
     @Override
     public final Collection<AnalysisMethod> getAllCallees() {
-        if (targetMethod.isImplementationInvoked()) {
+        return getAllCalleesHelper(false);
+    }
+
+    @Override
+    public final Collection<AnalysisMethod> getAllComputedCallees() {
+        return getAllCalleesHelper(true);
+    }
+
+    private Collection<AnalysisMethod> getAllCalleesHelper(boolean allComputed) {
+        if (allComputed || targetMethod.isImplementationInvoked()) {
             /*
              * When type states are filtered (e.g. due to context sensitivity), it is possible for a
              * callee to be set, but for it not to be linked.
              */
             Collection<AnalysisMethod> result = LightImmutableCollection.toCollection(this, CALLEES_ACCESSOR);
-            assert result.stream().filter(m -> m.isOriginalMethod()).allMatch(AnalysisMethod::isImplementationInvoked);
+            if (!allComputed) {
+                assert result.stream().filter(m -> m.isOriginalMethod()).allMatch(AnalysisMethod::isImplementationInvoked);
+            }
             return result;
         }
         return Collections.emptyList();

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

@@ -50,7 +50,7 @@ public abstract class InvokeTypeFlow extends TypeFlow<BytecodePosition> implemen
     /**
      * Result type flow returned by the callee.
      */
-    protected ActualReturnTypeFlow actualReturn;
+    protected volatile ActualReturnTypeFlow actualReturn;
 
     protected final InvokeTypeFlow originalInvoke;
 
@@ -270,6 +270,10 @@ protected void linkCallee(PointsToAnalysis bb, boolean isStatic, MethodFlowsGrap
     }
 
     public void linkReturn(PointsToAnalysis bb, boolean isStatic, MethodFlowsGraphInfo calleeFlows) {
+        /*
+         * If actualReturn is null, then there is no linking necessary. Later, if a typeflow is
+         * created for the return, then {@code setActualReturn} will perform all necessary linking.
+         */
         if (actualReturn != null && bb.getHostVM().getMultiMethodAnalysisPolicy().performReturnLinking(callerMultiMethodKey, calleeFlows.getMethod().getMultiMethodKey())) {
             if (bb.optimizeReturnedParameter()) {
                 int paramNodeIndex = calleeFlows.getMethod().getTypeFlow().getReturnedParameterIndex();
@@ -339,6 +343,12 @@ public Collection<AnalysisMethod> getOriginalCallees() {
     @Override
     public abstract Collection<AnalysisMethod> getAllCallees();
 
+    /**
+     * Returns all callees which have been computed for this method. It is possible that these
+     * callees have yet to have their typeflow created and also they may not be fully linked.
+     */
+    public abstract Collection<AnalysisMethod> getAllComputedCallees();
+
     @Override
     public BytecodePosition getPosition() {
         return getSource();

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

@@ -233,9 +233,14 @@ public boolean addOriginalObserver(PointsToAnalysis bb, TypeFlow<?> flow, TypeFl
 
     @Override
     public void linkActualReturn(PointsToAnalysis bb, boolean isStatic, InvokeTypeFlow invoke) {
-        /* Link the actual return with the formal return of already linked callees. */
-        for (AnalysisMethod callee : invoke.getAllCallees()) {
-            invoke.linkReturn(bb, isStatic, ((PointsToAnalysisMethod) callee).getTypeFlow().getMethodFlowsGraphInfo());
+        /*
+         * Link the actual return with the formal return of already linked callees. Note the callees
+         * may not be fully linked if they have been {@code DirectInvokeTypeFlow#initializeCallees}
+         * but not yet processed.
+         */
+        for (AnalysisMethod callee : invoke.getAllComputedCallees()) {
+            MethodFlowsGraphInfo calleeFlows = ((PointsToAnalysisMethod) callee).getTypeFlow().getOrCreateMethodFlowsGraphInfo(bb, invoke);
+            invoke.linkReturn(bb, isStatic, calleeFlows);
         }
         if (invoke.isSaturated()) {
             InvokeTypeFlow contextInsensitiveInvoke = invoke.getTargetMethod().getContextInsensitiveVirtualInvoke(invoke.getCallerMultiMethodKey());