Graal: native-image NPEs in IfNode.prepareForSwap() at com.github.ajalt.clikt.core.CliktCommand.main(List)

[mikaelhg]

Repro case: https://github.com/mikaelhg/graal-aot-clikt-repro

Including a particular library, clikt-1.3.0.jar, in a native-image compile results in a NPE in Graal code.

native-image bug.ReproKt --verbose -H:ReflectionConfigurationFiles=reflection.json -H:IncludeResources=.* -H:+ReportUnsupportedElementsAtRuntime -J-Dgraal.InlineDuringParsingMaxDepth=10 -cp build/classes/kotlin/main/:build/resources/main/:/home/mikael/.m2/repository/org/jetbrains/kotlin/kotlin-stdlib-jdk8/1.2.60/kotlin-stdlib-jdk8-1.2.60.jar:/home/mikael/.m2/repository/org/jetbrains/kotlin/kotlin-reflect/1.2.60/kotlin-reflect-1.2.60.jar:/home/mikael/.gradle/caches/modules-2/files-2.1/com.github.ajalt/clikt/1.3.0/eef12567763b8f1fa4f3096b7febfcd74842831f/clikt-1.3.0.jar:/home/mikael/.m2/repository/org/jetbrains/kotlin/kotlin-stdlib-jdk7/1.2.60/kotlin-stdlib-jdk7-1.2.60.jar:/home/mikael/.m2/repository/org/jetbrains/kotlin/kotlin-stdlib/1.2.60/kotlin-stdlib-1.2.60.jar:/home/mikael/.m2/repository/org/jetbrains/kotlin/kotlin-stdlib-common/1.2.60/kotlin-stdlib-common-1.2.60.jar:/home/mikael/.m2/repository/org/jetbrains/annotations/13.0/annotations-13.0.jar

       (cap):     695.67 ms
       setup:   1,256.57 ms
  (typeflow):   6,357.65 ms
   (objects):   5,444.75 ms
  (features):      66.51 ms
    analysis:  12,039.13 ms
    universe:     475.55 ms
     (parse):     386.07 ms
     compile:     394.36 ms
fatal error: org.graalvm.compiler.debug.GraalError: java.lang.NullPointerException
        at method: void com.github.ajalt.clikt.core.CliktCommand.main(List)
        at com.oracle.svm.hosted.code.CompileQueue.defaultParseFunction(CompileQueue.java:747)
        at com.oracle.svm.hosted.code.CompileQueue.doParse(CompileQueue.java:649)
        at com.oracle.svm.hosted.code.CompileQueue$ParseTask.run(CompileQueue.java:297)
        at com.oracle.graal.pointsto.util.CompletionExecutor.lambda$execute$0(CompletionExecutor.java:174)
        at java.util.concurrent.ForkJoinTask$RunnableExecuteAction.exec(ForkJoinTask.java:1402)
        at java.util.concurrent.ForkJoinTask.doExec(ForkJoinTask.java:289)
        at java.util.concurrent.ForkJoinPool$WorkQueue.runTask(ForkJoinPool.java:1056)
        at java.util.concurrent.ForkJoinPool.runWorker(ForkJoinPool.java:1692)
        at java.util.concurrent.ForkJoinWorkerThread.run(ForkJoinWorkerThread.java:157)
Caused by: java.lang.NullPointerException
        at org.graalvm.compiler.nodes.IfNode.prepareForSwap(IfNode.java:666)
        at org.graalvm.compiler.nodes.IfNode.simplify(IfNode.java:304)
        at org.graalvm.compiler.phases.common.CanonicalizerPhase$Instance.tryCanonicalize(CanonicalizerPhase.java:350)
        at org.graalvm.compiler.phases.common.CanonicalizerPhase$Instance.processNode(CanonicalizerPhase.java:262)
        at org.graalvm.compiler.phases.common.CanonicalizerPhase$Instance.processWorkSet(CanonicalizerPhase.java:241)
        at org.graalvm.compiler.phases.common.CanonicalizerPhase$Instance.run(CanonicalizerPhase.java:211)
        at org.graalvm.compiler.phases.common.CanonicalizerPhase.run(CanonicalizerPhase.java:125)
        at org.graalvm.compiler.phases.common.CanonicalizerPhase.run(CanonicalizerPhase.java:66)
        at org.graalvm.compiler.phases.BasePhase.apply(BasePhase.java:197)
        at org.graalvm.compiler.phases.BasePhase.apply(BasePhase.java:139)
        at com.oracle.svm.hosted.code.CompileQueue.defaultParseFunction(CompileQueue.java:718)
        ... 8 more
Error: Processing image build request failed

[mikaelhg]

[dougxc]

We had some lengthy internal discussion on how exactly to fix this and changed course in the process from a patch I came up with to a smaller, better patch by @christianwimmer :

diff --git a/compiler/src/org.graalvm.compiler.nodes/src/org/graalvm/compiler/nodes/java/InstanceOfNode.java b/compiler/src/org.graalvm.compiler.nodes/src/org/graalvm/compiler/nodes/java/InstanceOfNode.java
index 8b0b7433d00..ac9edbfc13f 100644
--- a/compiler/src/org.graalvm.compiler.nodes/src/org/graalvm/compiler/nodes/java/InstanceOfNode.java
+++ b/compiler/src/org.graalvm.compiler.nodes/src/org/graalvm/compiler/nodes/java/InstanceOfNode.java
@@ -61,7 +61,7 @@ import jdk.vm.ci.meta.TriState;
 public class InstanceOfNode extends UnaryOpLogicNode implements Lowerable, Virtualizable {
     public static final NodeClass<InstanceOfNode> TYPE = NodeClass.create(InstanceOfNode.class);

-    private ObjectStamp checkedStamp;
+    private final ObjectStamp checkedStamp;

     private JavaTypeProfile profile;
     @OptionalInput(Anchor) protected AnchoringNode anchor;
@@ -77,6 +77,7 @@ public class InstanceOfNode extends UnaryOpLogicNode implements Lowerable, Virtu
         this.anchor = anchor;
         assert (profile == null) || (anchor != null) : "profiles must be anchored";
         assert checkedStamp != null;
+        assert type() != null;
     }

     public static LogicNode createAllowNull(TypeReference type, ValueNode object, JavaTypeProfile profile, AnchoringNode anchor) {
@@ -217,11 +218,6 @@ public class InstanceOfNode extends UnaryOpLogicNode implements Lowerable, Virtu
         return checkedStamp;
     }

-    public void strengthenCheckedStamp(ObjectStamp newCheckedStamp) {
-        assert this.checkedStamp.join(newCheckedStamp).equals(newCheckedStamp) : "stamp can only improve";
-        this.checkedStamp = newCheckedStamp;
-    }
-
     @Override
     public TriState implies(boolean thisNegated, LogicNode other) {
         if (other instanceof InstanceOfNode) {
diff --git a/substratevm/src/com.oracle.svm.hosted/src/com/oracle/svm/hosted/phases/StrengthenStampsPhase.java b/substratevm/src/com.oracle.svm.hosted/src/com/oracle/svm/hosted/phases/StrengthenStampsPhase.java
index 5098ab6532e..1f80df51c66 100644
--- a/substratevm/src/com.oracle.svm.hosted/src/com/oracle/svm/hosted/phases/StrengthenStampsPhase.java
+++ b/substratevm/src/com.oracle.svm.hosted/src/com/oracle/svm/hosted/phases/StrengthenStampsPhase.java
@@ -104,7 +104,7 @@ public class StrengthenStampsPhase extends Phase {
                 InstanceOfNode node = (InstanceOfNode) n;
                 ObjectStamp newStamp = (ObjectStamp) strengthen(node.getCheckedStamp());
                 if (newStamp != null) {
-                    node.strengthenCheckedStamp(newStamp);
+                    node.replaceAndDelete(graph.addOrUniqueWithInputs(InstanceOfNode.createHelper(newStamp, node.getValue(), node.profile(), node.getAnchor())));
                 }

             } else if (n instanceof PiNode) {

It should land on github in the next 24 hours. Your reproducer was very helpful and I've confirmed that it is fixed by the pending change.

[christianwimmer]

Fixed in https://github.com/oracle/graal/commit/eda98eab2c11bec4f0ce7b74efe92ae49c185fc3

[mikaelhg]

Verified with 1.0.0 RC6.