8373508: C2: sinking CreateEx out of loop breaks the graph

Reviewed-by: thartmann, shade
Backport-of: 6ae3e064352a56c5be140fba1ad6d040219432b0

src/hotspot/share/opto/loopopts.cpp

@@ -1708,6 +1708,7 @@ void PhaseIdealLoop::try_sink_out_of_loop(Node* n) {
       !n->is_OpaqueInitializedAssertionPredicate() &&
       !n->is_OpaqueTemplateAssertionPredicate() &&
       !is_raw_to_oop_cast && // don't extend live ranges of raw oops
+      n->Opcode() != Op_CreateEx &&
       (KillPathsReachableByDeadTypeNode || !n->is_Type())
       ) {
     Node *n_ctrl = get_ctrl(n);

test/hotspot/jtreg/compiler/loopopts/TestCreateExSunkOutOfLoop.java

@@ -0,0 +1,73 @@
+/*
+ * Copyright (c) 2025 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 8373508
+ * @summary C2: sinking CreateEx out of loop breaks the graph
+ * @library /test/lib
+ * @run main/othervm -Xbatch ${test.main.class}
+ * @run main ${test.main.class}
+ */
+
+package compiler.loopopts;
+
+import jdk.test.lib.Utils;
+
+public class TestCreateExSunkOutOfLoop {
+    volatile boolean _mutatorToggle;
+
+    boolean _mutatorFlip() {
+        _mutatorToggle = !_mutatorToggle;
+        return _mutatorToggle;
+    }
+
+    void test() {
+        int idx = -845;
+        for (;;) {
+            try {
+                try {
+                    for (Object temp = new byte[idx];;) {;}
+                } finally {
+                    boolean flag = _mutatorFlip();
+                    _mutatorFlip();
+                    for (;;) {
+                        if (flag) {
+                            break;
+                        }
+                    }
+                }
+            } catch (Throwable $) {;}
+        }
+    }
+
+    public static void main(String[] strArr) throws InterruptedException {
+        Thread thread = new Thread(() -> {
+            TestCreateExSunkOutOfLoop t = new TestCreateExSunkOutOfLoop();
+            t.test();
+        });
+        thread.setDaemon(true);
+        thread.start();
+        Thread.sleep(Utils.adjustTimeout(4000));
+    }
+}

test/hotspot/jtreg/compiler/loopopts/TestCreateExSunkOutOfLoop2.java

@@ -0,0 +1,85 @@
+/*
+ * Copyright (c) 2025 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 8373508
+ * @summary C2: sinking CreateEx out of loop breaks the graph
+ * @run main/othervm -Xbatch -XX:-TieredCompilation ${test.main.class}
+ * @run main ${test.main.class}
+ */
+
+package compiler.loopopts;
+
+public class TestCreateExSunkOutOfLoop2 {
+    boolean b;
+
+    boolean getB() {
+        return b;
+    }
+
+    void test() {
+        int x = -845;
+
+        for (int i = 5; i > 1; i -= 2) {
+            try {
+                try {
+                    for (Object temp = new byte[x]; ; ) {
+                        // infinite loop
+                    }
+                } finally {
+                    int zeroLimit = 2;
+                    for (; zeroLimit < 4; zeroLimit *= 2) { }
+
+                    int zero = 34;
+                    for (int peel = 2; peel < zeroLimit; peel++) {
+                        zero = 0;
+                    }
+
+                    if (zero == 0) {
+                        // nop
+                    }
+
+                    int flagLimit = 2;
+                    for (; flagLimit < 4; flagLimit *= 2) { }
+
+                    boolean flag = getB();
+                    for (int peel = 2; peel < flagLimit; peel++) {
+                        if (flag) {
+                            break;
+                        }
+                    }
+                }
+            } catch (Throwable t) {
+                // ignored
+            }
+        }
+    }
+
+    public static void main(String[] strArr) {
+        TestCreateExSunkOutOfLoop2 t = new TestCreateExSunkOutOfLoop2();
+        for (int i = 0; i < 10_000; ++i) {
+            t.test();
+        }
+    }
+}