[GR-54900] Delete snippet template return node duplicate if alive.

PullRequest: graal/18135

Author: boris-spas

compiler/src/jdk.graal.compiler/src/jdk/graal/compiler/nodes/gc/CardTableBarrierSet.java

@@ -65,6 +65,9 @@ public BarrierType readBarrierType(LocationIdentity location, ValueNode address,
 
     @Override
     public BarrierType writeBarrierType(RawStoreNode store) {
+        if (store.object().isNullConstant()) {
+            return BarrierType.NONE;
+        }
         return store.needsBarrier() ? readWriteBarrier(store.object(), store.value()) : BarrierType.NONE;
     }
 

compiler/src/jdk.graal.compiler/src/jdk/graal/compiler/nodes/gc/G1BarrierSet.java

@@ -63,6 +63,9 @@ public BarrierType readBarrierType(LocationIdentity location, ValueNode address,
 
     @Override
     public BarrierType writeBarrierType(RawStoreNode store) {
+        if (store.object().isNullConstant()) {
+            return BarrierType.NONE;
+        }
         return store.needsBarrier() ? readWriteBarrier(store.object(), store.value()) : BarrierType.NONE;
     }
 

compiler/src/jdk.graal.compiler/src/jdk/graal/compiler/replacements/SnippetTemplate.java

@@ -2463,12 +2463,6 @@ public void instantiate(MetaAccessProvider metaAccess, FloatingNode replacee, Us
                 anchorDuplicate = replaceeGraph.add(new MemoryAnchorNode(info.privateLocations));
                 replacements.put(memoryAnchor, anchorDuplicate);
             }
-            List<Node> floatingNodes = new ArrayList<>(nodes.size() - 2);
-            for (Node n : nodes) {
-                if (n != entryPointNode && n != returnNode) {
-                    floatingNodes.add(n);
-                }
-            }
             UnmodifiableEconomicMap<Node, Node> duplicates = inlineSnippet(replacee, debug, replaceeGraph, replacements);
 
             // floating nodes are not state-splits not need to re-wire frame states
@@ -2481,6 +2475,10 @@ public void instantiate(MetaAccessProvider metaAccess, FloatingNode replacee, Us
             // Replace all usages of the replacee with the value returned by the snippet
             ValueNode returnValue = (ValueNode) duplicates.get(returnNode.result());
             replacer.replace(replacee, returnValue);
+            Node returnNodeDuplicate = duplicates.get(returnNode);
+            if (returnNodeDuplicate.isAlive()) {
+                returnNodeDuplicate.safeDelete();
+            }
 
             debug.dump(DebugContext.DETAILED_LEVEL, replaceeGraph, "After lowering %s with %s", replacee, this);
         } catch (Throwable e) {

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

@@ -55,6 +55,7 @@
 import com.oracle.graal.pointsto.BigBang;
 import com.oracle.graal.pointsto.ObjectScanner;
 import com.oracle.graal.pointsto.heap.ImageHeapConstant;
+import com.oracle.graal.pointsto.heap.ImageHeapScanner;
 import com.oracle.graal.pointsto.infrastructure.SubstitutionProcessor;
 import com.oracle.graal.pointsto.meta.AnalysisField;
 import com.oracle.graal.pointsto.meta.AnalysisMetaAccess;
@@ -631,6 +632,10 @@ public Collection<? extends SharedField> getFields() {
         public Collection<? extends SharedMethod> getMethods() {
             return hUniverse.getMethods();
         }
+
+        public ImageHeapScanner getHeapScanner() {
+            return aUniverse.getHeapScanner();
+        }
     }
 
     public static class BeforeCompilationAccessImpl extends CompilationAccessImpl implements Feature.BeforeCompilationAccess {