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diff --git a/asm-analysis/src/main/java/org/objectweb/asm/tree/analysis/SourceInterpreter.java b/asm-analysis/src/main/java/org/objectweb/asm/tree/analysis/SourceInterpreter.java
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+// ASM: a very small and fast Java bytecode manipulation framework
+// Copyright (c) 2000-2011 INRIA, France Telecom
+// All rights reserved.
+//
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions
+// are met:
+// 1. Redistributions of source code must retain the above copyright
+//    notice, this list of conditions and the following disclaimer.
+// 2. Redistributions in binary form must reproduce the above copyright
+//    notice, this list of conditions and the following disclaimer in the
+//    documentation and/or other materials provided with the distribution.
+// 3. Neither the name of the copyright holders nor the names of its
+//    contributors may be used to endorse or promote products derived from
+//    this software without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+// AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+// IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+// ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
+// LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+// CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+// SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+// INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+// CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+// ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
+// THE POSSIBILITY OF SUCH DAMAGE.
+package org.objectweb.asm.tree.analysis;
+
+import java.util.HashSet;
+import java.util.List;
+import java.util.Set;
+import org.objectweb.asm.Opcodes;
+import org.objectweb.asm.Type;
+import org.objectweb.asm.tree.AbstractInsnNode;
+import org.objectweb.asm.tree.FieldInsnNode;
+import org.objectweb.asm.tree.InvokeDynamicInsnNode;
+import org.objectweb.asm.tree.LdcInsnNode;
+import org.objectweb.asm.tree.MethodInsnNode;
+
+/**
+ * An {@link Interpreter} for {@link SourceValue} values.
+ *
+ * @author Eric Bruneton
+ */
+public class SourceInterpreter extends Interpreter<SourceValue> implements Opcodes {
+
+  /**
+   * Constructs a new {@link SourceInterpreter} for the latest ASM API version. <i>Subclasses must
+   * not use this constructor</i>. Instead, they must use the {@link #SourceInterpreter(int)}
+   * version.
+   */
+  public SourceInterpreter() {
+    super(/* latest api = */ ASM9);
+    if (getClass() != SourceInterpreter.class) {
+      throw new IllegalStateException();
+    }
+  }
+
+  /**
+   * Constructs a new {@link SourceInterpreter}.
+   *
+   * @param api the ASM API version supported by this interpreter. Must be one of the {@code
+   *     ASM}<i>x</i> values in {@link Opcodes}.
+   */
+  protected SourceInterpreter(final int api) {
+    super(api);
+  }
+
+  @Override
+  public SourceValue newValue(final Type type) {
+    if (type == Type.VOID_TYPE) {
+      return null;
+    }
+    return new SourceValue(type == null ? 1 : type.getSize());
+  }
+
+  @Override
+  public SourceValue newOperation(final AbstractInsnNode insn) {
+    int size;
+    switch (insn.getOpcode()) {
+      case LCONST_0:
+      case LCONST_1:
+      case DCONST_0:
+      case DCONST_1:
+        size = 2;
+        break;
+      case LDC:
+        Object value = ((LdcInsnNode) insn).cst;
+        size = value instanceof Long || value instanceof Double ? 2 : 1;
+        break;
+      case GETSTATIC:
+        size = Type.getType(((FieldInsnNode) insn).desc).getSize();
+        break;
+      default:
+        size = 1;
+        break;
+    }
+    return new SourceValue(size, insn);
+  }
+
+  @Override
+  public SourceValue copyOperation(final AbstractInsnNode insn, final SourceValue value) {
+    return new SourceValue(value.getSize(), insn);
+  }
+
+  @Override
+  public SourceValue unaryOperation(final AbstractInsnNode insn, final SourceValue value) {
+    int size;
+    switch (insn.getOpcode()) {
+      case LNEG:
+      case DNEG:
+      case I2L:
+      case I2D:
+      case L2D:
+      case F2L:
+      case F2D:
+      case D2L:
+        size = 2;
+        break;
+      case GETFIELD:
+        size = Type.getType(((FieldInsnNode) insn).desc).getSize();
+        break;
+      default:
+        size = 1;
+        break;
+    }
+    return new SourceValue(size, insn);
+  }
+
+  @Override
+  public SourceValue binaryOperation(
+      final AbstractInsnNode insn, final SourceValue value1, final SourceValue value2) {
+    int size;
+    switch (insn.getOpcode()) {
+      case LALOAD:
+      case DALOAD:
+      case LADD:
+      case DADD:
+      case LSUB:
+      case DSUB:
+      case LMUL:
+      case DMUL:
+      case LDIV:
+      case DDIV:
+      case LREM:
+      case DREM:
+      case LSHL:
+      case LSHR:
+      case LUSHR:
+      case LAND:
+      case LOR:
+      case LXOR:
+        size = 2;
+        break;
+      default:
+        size = 1;
+        break;
+    }
+    return new SourceValue(size, insn);
+  }
+
+  @Override
+  public SourceValue ternaryOperation(
+      final AbstractInsnNode insn,
+      final SourceValue value1,
+      final SourceValue value2,
+      final SourceValue value3) {
+    return new SourceValue(1, insn);
+  }
+
+  @Override
+  public SourceValue naryOperation(
+      final AbstractInsnNode insn, final List<? extends SourceValue> values) {
+    int size;
+    int opcode = insn.getOpcode();
+    if (opcode == MULTIANEWARRAY) {
+      size = 1;
+    } else if (opcode == INVOKEDYNAMIC) {
+      size = Type.getReturnType(((InvokeDynamicInsnNode) insn).desc).getSize();
+    } else {
+      size = Type.getReturnType(((MethodInsnNode) insn).desc).getSize();
+    }
+    return new SourceValue(size, insn);
+  }
+
+  @Override
+  public void returnOperation(
+      final AbstractInsnNode insn, final SourceValue value, final SourceValue expected) {
+    // Nothing to do.
+  }
+
+  @Override
+  public SourceValue merge(final SourceValue value1, final SourceValue value2) {
+    if (value1.insns instanceof SmallSet && value2.insns instanceof SmallSet) {
+      Set<AbstractInsnNode> setUnion =
+          ((SmallSet<AbstractInsnNode>) value1.insns)
+              .union((SmallSet<AbstractInsnNode>) value2.insns);
+      if (setUnion == value1.insns && value1.size == value2.size) {
+        return value1;
+      } else {
+        return new SourceValue(Math.min(value1.size, value2.size), setUnion);
+      }
+    }
+    if (value1.size != value2.size || !containsAll(value1.insns, value2.insns)) {
+      HashSet<AbstractInsnNode> setUnion = new HashSet<>();
+      setUnion.addAll(value1.insns);
+      setUnion.addAll(value2.insns);
+      return new SourceValue(Math.min(value1.size, value2.size), setUnion);
+    }
+    return value1;
+  }
+
+  private static <E> boolean containsAll(final Set<E> self, final Set<E> other) {
+    if (self.size() < other.size()) {
+      return false;
+    }
+    return self.containsAll(other);
+  }
+}