From 0cdb2549427a02c6d77adbbf29ba5ed1d1d38293 Mon Sep 17 00:00:00 2001
From: Christian Hagedorn <christian.hagedorn@oracle.com>
Date: Mon, 19 Jan 2026 15:18:57 +0100
Subject: [PATCH] 8375548: [lworld] C2: Compiler replay fails with an assertion
 due to not loading object array klasses with ArrayProperties::DEFAULT

---
 src/hotspot/share/ci/ciReplay.cpp             |  4 +
 .../ciReplay/TestLoadObjArrayKlass.java       | 84 +++++++++++++++++++
 2 files changed, 88 insertions(+)
 create mode 100644 test/hotspot/jtreg/compiler/ciReplay/TestLoadObjArrayKlass.java

diff --git a/src/hotspot/share/ci/ciReplay.cpp b/src/hotspot/share/ci/ciReplay.cpp
index 3a69bed4780..e8f7e1d1779 100644
--- a/src/hotspot/share/ci/ciReplay.cpp
+++ b/src/hotspot/share/ci/ciReplay.cpp
@@ -556,6 +556,10 @@ class CompileReplay : public StackObj {
       } else {
         k = SystemDictionary::resolve_or_fail(klass_name, _loader, true, THREAD);
       }
+      if (Arguments::is_valhalla_enabled() && k->is_objArray_klass()) {
+        // Create ref or flat array klass.
+        k = ObjArrayKlass::cast(k)->klass_with_properties(ArrayKlass::ArrayProperties::DEFAULT, THREAD);
+      }
       if (HAS_PENDING_EXCEPTION) {
         oop throwable = PENDING_EXCEPTION;
         java_lang_Throwable::print(throwable, tty);
diff --git a/test/hotspot/jtreg/compiler/ciReplay/TestLoadObjArrayKlass.java b/test/hotspot/jtreg/compiler/ciReplay/TestLoadObjArrayKlass.java
new file mode 100644
index 00000000000..8f2f00b0a4f
--- /dev/null
+++ b/test/hotspot/jtreg/compiler/ciReplay/TestLoadObjArrayKlass.java
@@ -0,0 +1,84 @@
+/*
+ * Copyright (c) 2026, Oracle and/or its affiliates. All rights reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ */
+
+/*
+ * @test
+ * @bug 8375548
+ * @enablePreview
+ * @library / /test/lib
+ * @summary Testing that compiler replay correctly loads sub classes of ObjArrayKlass.
+ * @requires vm.flightRecorder != true & vm.compMode != "Xint" & vm.compMode != "Xcomp" & vm.debug == true &
+ *           vm.compiler2.enabled
+ * @modules java.base/jdk.internal.misc
+ * @build jdk.test.whitebox.WhiteBox
+ * @run driver jdk.test.lib.helpers.ClassFileInstaller jdk.test.whitebox.WhiteBox
+ * @run main/othervm -Xbootclasspath/a:. -XX:+UnlockDiagnosticVMOptions -XX:+WhiteBoxAPI
+ *                   compiler.ciReplay.TestLoadObjArrayKlass
+ */
+
+package compiler.ciReplay;
+
+public class TestLoadObjArrayKlass extends DumpReplayBase {
+
+    public static void main(String[] args) {
+        new TestLoadObjArrayKlass().runTest("-XX:CompileCommand=dontinline,*::test", "--enable-preview", TIERED_DISABLED_VM_OPTION);
+    }
+
+    @Override
+    public void testAction() {
+        positiveTest(TIERED_DISABLED_VM_OPTION, "-XX:+ReplayIgnoreInitErrors", "--enable-preview");
+    }
+
+    @Override
+    public String getTestClass() {
+        return TestLoadObjArrayKlassTest.class.getName();
+    }
+}
+
+class TestLoadObjArrayKlassTest {
+    static Object[] oArr = new A[100];
+
+    public static void main(String[] args) {
+        oArr[0] = new A();
+        for (int i = 0; i < 10000; i++) {
+            test();
+        }
+    }
+
+    static void test() {
+        Object[] oA = oArr;
+        Object o = oA[0];
+        // Use the object with its speculated type. This triggers the code path to call
+        //
+        //     Parse::create_speculative_inline_type_array_checks()
+        //     ...
+        //     ciArrayKlass::is_elem_null_free()
+        //
+        // which tries to directly query a ObjectArrayKlass instance in compiler replay instead of one of its subclasses
+        // (i.e. RefArrayKlass or FlatArrayKlass). This is unexpected and results in an assertion failure.
+        o.toString();
+    }
+
+    static value class A {
+    }
+}