From 07a52da1fed10623f66bf424a1c5b10bd07ad25e Mon Sep 17 00:00:00 2001
From: Roland Westrelin <roland@openjdk.org>
Date: Thu, 25 Jun 2026 07:15:18 +0000
Subject: [PATCH] 8387015: C2: crash with "named projection 2 not found" from
 ArrayCopyNode::finish_transform() for clone

Reviewed-by: qamai, kvn
---
 src/hotspot/share/opto/arraycopynode.cpp      |  6 ++
 .../compiler/arraycopy/TestDeadCloneMem.java  | 79 +++++++++++++++++++
 2 files changed, 85 insertions(+)
 create mode 100644 test/hotspot/jtreg/compiler/arraycopy/TestDeadCloneMem.java

diff --git a/src/hotspot/share/opto/arraycopynode.cpp b/src/hotspot/share/opto/arraycopynode.cpp
index 2f64482f55b..07b9e907b8f 100644
--- a/src/hotspot/share/opto/arraycopynode.cpp
+++ b/src/hotspot/share/opto/arraycopynode.cpp
@@ -180,6 +180,12 @@ Node* ArrayCopyNode::try_clone_instance(PhaseGVN *phase, bool can_reshape, int c
     return nullptr;
   }
 
+  Node* out_mem = proj_out_or_null(TypeFunc::Memory);
+  if (can_reshape && out_mem == nullptr) { // dead node?
+    return NodeSentinel;
+  }
+
+
   Node* base_src = in(ArrayCopyNode::Src);
   Node* base_dest = in(ArrayCopyNode::Dest);
   Node* ctl = in(TypeFunc::Control);
diff --git a/test/hotspot/jtreg/compiler/arraycopy/TestDeadCloneMem.java b/test/hotspot/jtreg/compiler/arraycopy/TestDeadCloneMem.java
new file mode 100644
index 00000000000..807f45f11f7
--- /dev/null
+++ b/test/hotspot/jtreg/compiler/arraycopy/TestDeadCloneMem.java
@@ -0,0 +1,79 @@
+/*
+ * Copyright (c) 2026 IBM Corporation. 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 JDK-8387015
+ * @summary C2: crash with "named projection 2 not found" from ArrayCopyNode::finish_transform() for clone
+ * @run main/othervm -Xcomp -XX:+UnlockDiagnosticVMOptions -XX:CompileOnly=${test.main.class}::test1
+ *                   -XX:CompileCommand=dontinline,${test.main.class}::notInlined -XX:+StressIGVN
+ *                   -XX:StressSeed=1324432947 ${test.main.class}
+ * @run main/othervm -Xcomp -XX:+UnlockDiagnosticVMOptions -XX:CompileOnly=${test.main.class}::test1
+ *                   -XX:CompileCommand=dontinline,${test.main.class}::notInlined -XX:+StressIGVN
+ *                   ${test.main.class}
+ */
+
+package compiler.arraycopy;
+
+public class TestDeadCloneMem {
+    private static int field;
+
+    public static void main(String[] args) {
+        int[] array = new int[10];
+        array.clone();
+        Object o = new Object();
+        test1(42, false);
+    }
+
+    private static int test1(int flag, boolean flag2) {
+        int len;
+        if (flag != 42) {
+            if (flag2) {
+                field = 42;
+            }
+            int[] array2;
+            if (flag != 42) {
+                len = -1;
+                array2 = new int[4];
+            } else {
+                len = 42;
+                array2 = new int[100];
+            }
+            int[] array = new int[len];
+            int length = array.length;
+            int i = 0;
+            do {
+                synchronized (new Object()) {}
+                notInlined();
+                array2.clone();
+                i++;
+            } while (i < 10);
+            return length;
+        }
+        return 0;
+    }
+
+    private static void notInlined() {
+
+    }
+}