OpenVADL · flofriday · Jun 25, 2026
diff --git a/java-annotations/main/vadl/javaannotations/viam/CollectInputsChecker.java b/java-annotations/main/vadl/javaannotations/viam/CollectInputsChecker.java
@@ -1,4 +1,4 @@
-// SPDX-FileCopyrightText : © 2025 TU Wien <vadl@tuwien.ac.at>
+// SPDX-FileCopyrightText : © 2025-2026 TU Wien <vadl@tuwien.ac.at>
 // SPDX-License-Identifier: GPL-3.0-or-later
 //
 // This program is free software: you can redistribute it and/or modify
@@ -19,33 +19,36 @@
 import com.google.auto.service.AutoService;
 import com.google.errorprone.BugPattern;
 import com.google.errorprone.bugpatterns.BugChecker;
+import com.google.errorprone.util.ASTHelpers;
 import com.sun.source.tree.VariableTree;
+import java.util.ArrayList;
 import java.util.List;
 import vadl.javaannotations.AbstractAnnotationChecker;
 
 /**
  * The CollectInputsChecker class is a bug checker that checks for classes with fields
- * annotated with @Input and ensures that they override the collectInputs method.
+ * annotated with @Input and ensures that they override the forEachInput method.
  * It will fail if its implementation is not as expected.
  */
 @AutoService(BugChecker.class)
 @BugPattern(
     name = "CollectInputs",
-    summary = "Classes with @Input annotated fields must override the collectInputs method",
+    summary = "Classes with @Input annotated fields must override the forEachInput method",
     severity = BugPattern.SeverityLevel.ERROR
 )
 @SuppressWarnings("BugPatternNaming")
-public class CollectInputsChecker extends AbstractAnnotationChecker implements DefaultCollectMixin {
+public class CollectInputsChecker extends AbstractAnnotationChecker {
 
-  private static final String PARAM_TYPE = "java.util.List" + "<" + CheckerUtils.NODE + ">";
+  private static final String PARAM_TYPE =
+      "java.util.function.Consumer" + "<" + CheckerUtils.NODE + ">";
 
   /**
    * Constructs the bug checker.
    */
   public CollectInputsChecker() {
     super(
         Input.class,
-        "collectInputs",
+        "forEachInput",
         "void",
         List.of(PARAM_TYPE)
     );
@@ -54,6 +57,27 @@ public CollectInputsChecker() {
   @Override
   protected List<String> expectedMethodStatements(List<String> paramNames,
                                                   List<VariableTree> fields) {
-    return defaultCollectStatements(methodName, paramNames, fields, true);
+    var stmts = new ArrayList<String>();
+    var consumerName = paramNames.get(0);
+
+    stmts.add("super.%s(%s);".formatted(methodName, consumerName));
+    for (var field : fields) {
+      var type = ASTHelpers.getType(field);
+      assert type != null;
+
+      var hasAnnotation = ASTHelpers
+          .hasDirectAnnotationWithSimpleName(field, "Nullable");
+
+      var stmt = type.toString().startsWith(CheckerUtils.NODELIST)
+          ? "%s.forEach(%s);".formatted(field.getName(), consumerName)
+          : "%s.accept(%s);".formatted(consumerName, field.getName());
+
+      if (hasAnnotation) {
+        stmt = "if (this.%s != null) { %s }".formatted(field.getName(), stmt);
+      }
+
+      stmts.add(stmt);
+    }
+    return stmts;
   }
 }
diff --git a/java-annotations/main/vadl/javaannotations/viam/CollectSuccessorsChecker.java b/java-annotations/main/vadl/javaannotations/viam/CollectSuccessorsChecker.java
@@ -1,4 +1,4 @@
-// SPDX-FileCopyrightText : © 2025 TU Wien <vadl@tuwien.ac.at>
+// SPDX-FileCopyrightText : © 2025-2026 TU Wien <vadl@tuwien.ac.at>
 // SPDX-License-Identifier: GPL-3.0-or-later
 //
 // This program is free software: you can redistribute it and/or modify
@@ -19,34 +19,36 @@
 import com.google.auto.service.AutoService;
 import com.google.errorprone.BugPattern;
 import com.google.errorprone.bugpatterns.BugChecker;
+import com.google.errorprone.util.ASTHelpers;
 import com.sun.source.tree.VariableTree;
+import java.util.ArrayList;
 import java.util.List;
 import vadl.javaannotations.AbstractAnnotationChecker;
 
 /**
  * The CollectSuccessorsChecker class is a bug checker that checks for classes with @Successor
- * annotated fields that must override the collectSuccessors method.
+ * annotated fields that must override the forEachSuccessor method.
  * It will fail if the method implementation is not as expected.
  */
 @AutoService(BugChecker.class)
 @BugPattern(
     name = "CollectSuccessors",
-    summary = "Classes with @Successor annotated fields must override the collectSuccessors method",
+    summary = "Classes with @Successor annotated fields must override the forEachSuccessor method",
     severity = BugPattern.SeverityLevel.ERROR
 )
 @SuppressWarnings("BugPatternNaming")
-public class CollectSuccessorsChecker extends AbstractAnnotationChecker
-    implements DefaultCollectMixin {
+public class CollectSuccessorsChecker extends AbstractAnnotationChecker {
 
-  private static final String PARAM_TYPE = "java.util.List<" + CheckerUtils.NODE + ">";
+  private static final String PARAM_TYPE =
+      "java.util.function.Consumer" + "<" + CheckerUtils.NODE + ">";
 
   /**
    * Constructs the bug checker.
    */
   public CollectSuccessorsChecker() {
     super(
         Successor.class,
-        "collectSuccessors",
+        "forEachSuccessor",
         "void",
         List.of(PARAM_TYPE)
     );
@@ -55,6 +57,27 @@ public CollectSuccessorsChecker() {
   @Override
   protected List<String> expectedMethodStatements(List<String> paramNames,
                                                   List<VariableTree> fields) {
-    return defaultCollectStatements(methodName, paramNames, fields, true);
+    var stmts = new ArrayList<String>();
+    var consumerName = paramNames.get(0);
+
+    stmts.add("super.%s(%s);".formatted(methodName, consumerName));
+    for (var field : fields) {
+      var type = ASTHelpers.getType(field);
+      assert type != null;
+
+      var hasAnnotation = ASTHelpers
+          .hasDirectAnnotationWithSimpleName(field, "Nullable");
+
+      var stmt = type.toString().startsWith(CheckerUtils.NODELIST)
+          ? "%s.forEach(%s);".formatted(field.getName(), consumerName)
+          : "%s.accept(%s);".formatted(consumerName, field.getName());
+
+      if (hasAnnotation) {
+        stmt = "if (this.%s != null) { %s }".formatted(field.getName(), stmt);
+      }
+
+      stmts.add(stmt);
+    }
+    return stmts;
   }
 }
diff --git a/vadl/main/vadl/cppCodeGen/model/nodes/CppUpdateBitRangeNode.java b/vadl/main/vadl/cppCodeGen/model/nodes/CppUpdateBitRangeNode.java
@@ -1,4 +1,4 @@
-// SPDX-FileCopyrightText : © 2025 TU Wien <vadl@tuwien.ac.at>
+// SPDX-FileCopyrightText : © 2025-2026 TU Wien <vadl@tuwien.ac.at>
 // SPDX-License-Identifier: GPL-3.0-or-later
 //
 // This program is free software: you can redistribute it and/or modify
@@ -18,6 +18,7 @@
 
 
 import java.util.List;
+import java.util.function.Consumer;
 import vadl.cppCodeGen.CppCodeGenGraphNodeVisitor;
 import vadl.javaannotations.viam.DataValue;
 import vadl.javaannotations.viam.Input;
@@ -76,10 +77,10 @@ public <T extends GraphNodeVisitor> void accept(T visitor) {
   }
 
   @Override
-  protected void collectInputs(List<Node> collection) {
-    super.collectInputs(collection);
-    collection.add(value);
-    collection.add(patch);
+  protected void forEachInput(Consumer<Node> consumer) {
+    super.forEachInput(consumer);
+    consumer.accept(value);
+    consumer.accept(patch);
   }
 
   @Override

diff --git a/vadl/main/vadl/iss/passes/common/opDecomposition/nodes/IssBinaryNode.java b/vadl/main/vadl/iss/passes/common/opDecomposition/nodes/IssBinaryNode.java
@@ -16,7 +16,7 @@
 
 package vadl.iss.passes.common.opDecomposition.nodes;
 
-import java.util.List;
+import java.util.function.Consumer;
 import vadl.javaannotations.viam.Input;
 import vadl.types.Type;
 import vadl.viam.graph.GraphVisitor;
@@ -64,9 +64,9 @@ protected void applyOnInputsUnsafe(GraphVisitor.Applier<Node> visitor) {
   }
 
   @Override
-  protected void collectInputs(List<Node> collection) {
-    super.collectInputs(collection);
-    collection.add(arg1);
-    collection.add(arg2);
+  protected void forEachInput(Consumer<Node> consumer) {
+    super.forEachInput(consumer);
+    consumer.accept(arg1);
+    consumer.accept(arg2);
   }
 }
diff --git a/vadl/main/vadl/iss/passes/common/safeResourceRead/nodes/ExprSaveNode.java b/vadl/main/vadl/iss/passes/common/safeResourceRead/nodes/ExprSaveNode.java
@@ -16,7 +16,7 @@
 
 package vadl.iss.passes.common.safeResourceRead.nodes;
 
-import java.util.List;
+import java.util.function.Consumer;
 import vadl.javaannotations.viam.Input;
 import vadl.viam.graph.GraphNodeVisitor;
 import vadl.viam.graph.GraphVisitor;
@@ -70,9 +70,9 @@ public <T extends GraphNodeVisitor> void accept(T visitor) {
   }
 
   @Override
-  protected void collectInputs(List<Node> collection) {
-    super.collectInputs(collection);
-    collection.add(value);
+  protected void forEachInput(Consumer<Node> consumer) {
+    super.forEachInput(consumer);
+    consumer.accept(value);
   }
 
   @Override

diff --git a/vadl/main/vadl/iss/passes/nodes/IssConstExtractNode.java b/vadl/main/vadl/iss/passes/nodes/IssConstExtractNode.java
@@ -17,6 +17,7 @@
 package vadl.iss.passes.nodes;
 
 import java.util.List;
+import java.util.function.Consumer;
 import vadl.iss.passes.common.opDecomposition.nodes.IssExprNode;
 import vadl.iss.passes.tcg.lowering.TcgExtend;
 import vadl.javaannotations.viam.DataValue;
@@ -153,9 +154,9 @@ protected void collectData(List<Object> collection) {
   }
 
   @Override
-  protected void collectInputs(List<Node> collection) {
-    super.collectInputs(collection);
-    collection.add(value);
+  protected void forEachInput(Consumer<Node> consumer) {
+    super.forEachInput(consumer);
+    consumer.accept(value);
   }
 
   @Override

diff --git a/vadl/main/vadl/iss/passes/nodes/IssGhostCastNode.java b/vadl/main/vadl/iss/passes/nodes/IssGhostCastNode.java
@@ -16,7 +16,7 @@
 
 package vadl.iss.passes.nodes;
 
-import java.util.List;
+import java.util.function.Consumer;
 import vadl.iss.passes.common.opDecomposition.nodes.IssExprNode;
 import vadl.javaannotations.viam.Input;
 import vadl.types.DataType;
@@ -77,9 +77,9 @@ public <T extends GraphNodeVisitor> void accept(T visitor) {
   }
 
   @Override
-  protected void collectInputs(List<Node> collection) {
-    super.collectInputs(collection);
-    collection.add(value);
+  protected void forEachInput(Consumer<Node> consumer) {
+    super.forEachInput(consumer);
+    consumer.accept(value);
   }
 
   @Override

diff --git a/vadl/main/vadl/iss/passes/nodes/IssGvecOpNode.java b/vadl/main/vadl/iss/passes/nodes/IssGvecOpNode.java
@@ -17,6 +17,7 @@
 package vadl.iss.passes.nodes;
 
 import java.util.List;
+import java.util.function.Consumer;
 import javax.annotation.Nullable;
 import vadl.iss.passes.extensions.VectorTensorPlan;
 import vadl.iss.passes.extensions.VectorTensorPlan.OperandForm;
@@ -231,16 +232,16 @@ public <T extends GraphNodeVisitor> void accept(T visitor) {
   }
 
   @Override
-  protected void collectInputs(List<Node> collection) {
-    super.collectInputs(collection);
-    collection.addAll(destinationAccessorIndices);
-    collection.addAll(lhsAccessorIndices);
-    collection.addAll(rhsAccessorIndices);
+  protected void forEachInput(Consumer<Node> consumer) {
+    super.forEachInput(consumer);
+    destinationAccessorIndices.forEach(consumer);
+    lhsAccessorIndices.forEach(consumer);
+    rhsAccessorIndices.forEach(consumer);
     if (this.scalarOperand != null) {
-      collection.add(scalarOperand);
+      consumer.accept(scalarOperand);
     }
     if (this.immediateOperand != null) {
-      collection.add(immediateOperand);
+      consumer.accept(immediateOperand);
     }
   }
 

diff --git a/vadl/main/vadl/iss/passes/nodes/IssMoveNode.java b/vadl/main/vadl/iss/passes/nodes/IssMoveNode.java
@@ -1,4 +1,4 @@
-// SPDX-FileCopyrightText : © 2025 TU Wien <vadl@tuwien.ac.at>
+// SPDX-FileCopyrightText : © 2025-2026 TU Wien <vadl@tuwien.ac.at>
 // SPDX-License-Identifier: GPL-3.0-or-later
 //
 // This program is free software: you can redistribute it and/or modify
@@ -16,7 +16,7 @@
 
 package vadl.iss.passes.nodes;
 
-import java.util.List;
+import java.util.function.Consumer;
 import vadl.javaannotations.viam.Input;
 import vadl.viam.graph.GraphNodeVisitor;
 import vadl.viam.graph.GraphVisitor;
@@ -66,10 +66,10 @@ public <T extends GraphNodeVisitor> void accept(T visitor) {
   }
 
   @Override
-  protected void collectInputs(List<Node> collection) {
-    super.collectInputs(collection);
-    collection.add(dest);
-    collection.add(expr);
+  protected void forEachInput(Consumer<Node> consumer) {
+    super.forEachInput(consumer);
+    consumer.accept(dest);
+    consumer.accept(expr);
   }
 
   @Override

diff --git a/vadl/main/vadl/iss/passes/nodes/IssReadRegNode.java b/vadl/main/vadl/iss/passes/nodes/IssReadRegNode.java
@@ -19,6 +19,7 @@
 import com.google.common.collect.Streams;
 import java.util.List;
 import java.util.Objects;
+import java.util.function.Consumer;
 import javax.annotation.Nullable;
 import vadl.javaannotations.viam.DataValue;
 import vadl.javaannotations.viam.Input;
@@ -28,6 +29,7 @@
 import vadl.viam.Constant;
 import vadl.viam.Counter;
 import vadl.viam.RegisterTensor;
+import vadl.viam.graph.Node;
 import vadl.viam.graph.NodeList;
 import vadl.viam.graph.dependency.ConstantNode;
 import vadl.viam.graph.dependency.ExpressionNode;
@@ -290,11 +292,11 @@ public IssReadRegNode shallowCopy() {
   }
 
   @Override
-  protected void collectInputs(List<vadl.viam.graph.Node> collection) {
-    super.collectInputs(collection);
-    collection.addAll(accessorIndices);
-    collection.add(bitOffset);
-    collection.add(bitWidth);
+  protected void forEachInput(Consumer<Node> consumer) {
+    super.forEachInput(consumer);
+    accessorIndices.forEach(consumer);
+    consumer.accept(bitOffset);
+    consumer.accept(bitWidth);
   }
 
   @Override

diff --git a/vadl/main/vadl/iss/passes/nodes/IssRegBitfieldWriteNode.java b/vadl/main/vadl/iss/passes/nodes/IssRegBitfieldWriteNode.java
@@ -17,6 +17,7 @@
 package vadl.iss.passes.nodes;
 
 import java.util.List;
+import java.util.function.Consumer;
 import javax.annotation.Nullable;
 import vadl.javaannotations.viam.DataValue;
 import vadl.javaannotations.viam.Input;
@@ -118,12 +119,12 @@ public void verifyState() {
   }
 
   @Override
-  protected void collectInputs(List<Node> collection) {
-    super.collectInputs(collection);
-    collection.addAll(indices);
-    collection.add(value);
-    collection.add(bitOffset);
-    collection.add(bitWidth);
+  protected void forEachInput(Consumer<Node> consumer) {
+    super.forEachInput(consumer);
+    indices.forEach(consumer);
+    consumer.accept(value);
+    consumer.accept(bitOffset);
+    consumer.accept(bitWidth);
   }
 
   @Override