Merge to tag jdk-26+32

src/hotspot/cpu/x86/c2_stubGenerator_x86_64_string.cpp

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2024, 2025, Intel Corporation. All rights reserved.
+ * Copyright (c) 2024, 2026, Intel Corporation. All rights reserved.
  *
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
@@ -1330,10 +1330,12 @@ static void big_case_loop_helper(bool sizeKnown, int size, Label &noMatch, Label
   // Clarification:  The BYTE_K compare above compares haystack[(n-32):(n-1)].  We need to
   // compare haystack[(k-1):(k-1+31)].  Subtracting either index gives shift value of
   // (k + 31 - n):  x = (k-1+31)-(n-1) = k-1+31-n+1 = k+31-n.
+  // When isU is set, similarly, shift is from haystack[(n-32):(n-1)] to [(k-2):(k-2+31)]
+
   if (sizeKnown) {
-    __ movl(temp2, 31 + size);
+    __ movl(temp2, (isU ? 30 : 31) + size);
   } else {
-    __ movl(temp2, 31);
+    __ movl(temp2, isU ? 30 : 31);
     __ addl(temp2, needleLen);
   }
   __ subl(temp2, hsLength);

src/java.base/share/classes/java/util/concurrent/CopyOnWriteArraySet.java

@@ -35,6 +35,13 @@
 
 package java.util.concurrent;
 
+import jdk.internal.misc.Unsafe;
+
+import java.io.IOException;
+import java.io.ObjectInputStream;
+import java.io.ObjectStreamException;
+import java.io.Serial;
+import java.io.StreamCorruptedException;
 import java.util.AbstractSet;
 import java.util.Collection;
 import java.util.Iterator;
@@ -445,4 +452,38 @@ public Spliterator<E> spliterator() {
         return Spliterators.spliterator
             (al.getArray(), Spliterator.IMMUTABLE | Spliterator.DISTINCT);
     }
+
+    /**
+     * De-serialization without data not supported for this class.
+     */
+    @Serial
+    private void readObjectNoData() throws ObjectStreamException {
+        throw new StreamCorruptedException("Deserialized CopyOnWriteArraySet requires data");
+    }
+
+    /**
+     * Reconstitutes the {@code CopyOnWriteArraySet} instance from a stream
+     * (that is, deserializes it).
+     * @throws StreamCorruptedException if the object read from the stream is invalid.
+     */
+    @Serial
+    private void readObject(ObjectInputStream in) throws IOException, ClassNotFoundException {
+        CopyOnWriteArrayList<E> newAl; // Set during the duplicate check
+
+        @SuppressWarnings("unchecked")
+        CopyOnWriteArrayList<E> inAl = (CopyOnWriteArrayList<E>) in.readFields().get("al", null);
+
+        if (inAl == null
+                || inAl.getClass() != CopyOnWriteArrayList.class
+                || (newAl = new CopyOnWriteArrayList<>()).addAllAbsent(inAl) != inAl.size()) {
+            throw new StreamCorruptedException("Content is invalid");
+        }
+
+        final Unsafe U = Unsafe.getUnsafe();
+        U.putReference(
+                this,
+                U.objectFieldOffset(CopyOnWriteArraySet.class, "al"),
+                newAl
+        );
+    }
 }