update equals on wcpoperation due to Bytes32 equal method inconsistency.

arithmetization/src/main/java/net/consensys/linea/zktracer/types/EWord.java

@@ -214,4 +214,28 @@ public static EWord ofQuantity(final Quantity quantity) {
   public int byteLength() {
     return (this.bitLength() + 7) / 8;
   }
+
+  @Override
+  public boolean equals(Object obj) {
+    if (obj == this) {
+      return true;
+    }
+    if (!(obj instanceof Bytes)) {
+      return false;
+    }
+
+    Bytes other = (Bytes) obj;
+    if (this.size() != other.size()) {
+      return false;
+    }
+
+    // start from the end for perf reasons as ewords often start with 0s.
+    for (int i = this.size() - 1; i >= 0; i--) {
+      if (this.get(i) != other.get(i)) {
+        return false;
+      }
+    }
+
+    return true;
+  }
 }

arithmetization/src/test/java/net/consensys/linea/zktracer/container/stacked/WcpOperationTests.java

@@ -0,0 +1,49 @@
+/*
+ * Copyright ConsenSys Inc.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with
+ * the License. You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on
+ * an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the
+ * specific language governing permissions and limitations under the License.
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+package net.consensys.linea.zktracer.container.stacked;
+
+import net.consensys.linea.zktracer.module.wcp.WcpOperation;
+import net.consensys.linea.zktracer.types.EWord;
+import org.apache.tuweni.bytes.Bytes32;
+import org.junit.jupiter.api.Assertions;
+import org.junit.jupiter.api.Test;
+
+class WcpOperationTests {
+
+  @Test
+  void equals() {
+    Bytes32 a = Bytes32.ZERO.copy().mutableCopy();
+    EWord ew = EWord.ofHexString(a.toHexString());
+    // Even though both are Bytes32, the equal method fails on them:
+    // Assertions.assertTrue(ew.equals(a));
+
+    WcpOperation wo1 = new WcpOperation(WcpOperation.LEQbv, a, a);
+    WcpOperation wo2 = new WcpOperation(WcpOperation.LEQbv, ew, ew);
+    Assertions.assertTrue(wo1.equals(wo2));
+    Assertions.assertTrue(wo2.equals(wo1));
+  }
+
+  @Test
+  void different() {
+    Bytes32 a = Bytes32.ZERO.copy().mutableCopy();
+    EWord ew = EWord.ofHexString(Bytes32.repeat((byte) 1).toHexString());
+
+    WcpOperation wo1 = new WcpOperation(WcpOperation.LEQbv, a, a);
+    WcpOperation wo2 = new WcpOperation(WcpOperation.LEQbv, ew, ew);
+    Assertions.assertFalse(wo1.equals(wo2));
+    Assertions.assertFalse(wo2.equals(wo1));
+  }
+}