1 files changed, 138 insertions, 0 deletions

diff --git a/src/main/java/cuchaz/enigma/analysis/InterpreterPair.java b/src/main/java/cuchaz/enigma/analysis/InterpreterPair.java
new file mode 100644
index 0000000..af74c85
--- /dev/null
+++ b/src/main/java/cuchaz/enigma/analysis/InterpreterPair.java
@@ -0,0 +1,138 @@
+package cuchaz.enigma.analysis;
+
+import org.objectweb.asm.Opcodes;
+import org.objectweb.asm.Type;
+import org.objectweb.asm.tree.AbstractInsnNode;
+import org.objectweb.asm.tree.analysis.AnalyzerException;
+import org.objectweb.asm.tree.analysis.Interpreter;
+import org.objectweb.asm.tree.analysis.Value;
+
+import java.util.List;
+import java.util.Objects;
+import java.util.stream.Collectors;
+
+public class InterpreterPair<V extends Value, W extends Value> extends Interpreter<InterpreterPair.PairValue<V, W>> {
+    private final Interpreter<V> left;
+    private final Interpreter<W> right;
+
+    public InterpreterPair(Interpreter<V> left, Interpreter<W> right) {
+        super(Opcodes.ASM7);
+        this.left = left;
+        this.right = right;
+    }
+
+    @Override
+    public PairValue<V, W> newValue(Type type) {
+        return pair(
+                left.newValue(type),
+                right.newValue(type)
+        );
+    }
+
+    @Override
+    public PairValue<V, W> newOperation(AbstractInsnNode insn) throws AnalyzerException {
+        return pair(
+                left.newOperation(insn),
+                right.newOperation(insn)
+        );
+    }
+
+    @Override
+    public PairValue<V, W> copyOperation(AbstractInsnNode insn, PairValue<V, W> value) throws AnalyzerException {
+        return pair(
+                left.copyOperation(insn, value.left),
+                right.copyOperation(insn, value.right)
+        );
+    }
+
+    @Override
+    public PairValue<V, W> unaryOperation(AbstractInsnNode insn, PairValue<V, W> value) throws AnalyzerException {
+        return pair(
+                left.unaryOperation(insn, value.left),
+                right.unaryOperation(insn, value.right)
+        );
+    }
+
+    @Override
+    public PairValue<V, W> binaryOperation(AbstractInsnNode insn, PairValue<V, W> value1, PairValue<V, W> value2) throws AnalyzerException {
+        return pair(
+                left.binaryOperation(insn, value1.left, value2.left),
+                right.binaryOperation(insn, value1.right, value2.right)
+        );
+    }
+
+    @Override
+    public PairValue<V, W> ternaryOperation(AbstractInsnNode insn, PairValue<V, W> value1, PairValue<V, W> value2, PairValue<V, W> value3) throws AnalyzerException {
+        return pair(
+                left.ternaryOperation(insn, value1.left, value2.left, value3.left),
+                right.ternaryOperation(insn, value1.right, value2.right, value3.right)
+        );
+    }
+
+    @Override
+    public PairValue<V, W> naryOperation(AbstractInsnNode insn, List<? extends PairValue<V, W>> values) throws AnalyzerException {
+        return pair(
+                left.naryOperation(insn, values.stream().map(v -> v.left).collect(Collectors.toList())),
+                right.naryOperation(insn, values.stream().map(v -> v.right).collect(Collectors.toList()))
+        );
+    }
+
+    @Override
+    public void returnOperation(AbstractInsnNode insn, PairValue<V, W> value, PairValue<V, W> expected) throws AnalyzerException {
+        left.returnOperation(insn, value.left, expected.left);
+        right.returnOperation(insn, value.right, expected.right);
+    }
+
+    @Override
+    public PairValue<V, W> merge(PairValue<V, W> value1, PairValue<V, W> value2) {
+        return pair(
+                left.merge(value1.left, value2.left),
+                right.merge(value1.right, value2.right)
+        );
+    }
+
+    private PairValue<V, W> pair(V left, W right) {
+        if (left == null && right == null) {
+            return null;
+        }
+
+        if (left != null && right != null && left.getSize() != right.getSize()) {
+            throw new IllegalStateException("sizes don't match");
+        }
+
+        return new PairValue<>(left, right);
+    }
+
+    public static final class PairValue<V extends Value, W extends Value> implements Value {
+        public final V left;
+        public final W right;
+
+        public PairValue(V left, W right) {
+            if (left == null && right == null) {
+                throw new IllegalArgumentException("should use null rather than pair of nulls");
+            }
+
+            if (left != null && right != null && left.getSize() != right.getSize()) {
+                throw new IllegalArgumentException("sizes don't match");
+            }
+
+            this.left = left;
+            this.right = right;
+        }
+
+        @Override
+        public boolean equals(Object o) {
+            return o instanceof InterpreterPair.PairValue && Objects.equals(left, ((PairValue) o).left) && Objects.equals(right, ((PairValue) o).right);
+        }
+
+        @Override
+        public int hashCode() {
+            return left.hashCode() * 31 + right.hashCode();
+        }
+
+        @Override
+        public int getSize() {
+            return (left == null ? right : left).getSize();
+        }
+    }
+}