[GR-51813] Guard against deleting canonicalizer replacement.

PullRequest: graal/16837

compiler/src/jdk.graal.compiler.test/src/jdk/graal/compiler/replacements/test/HotSpotReflectionGetCallerClassTest.java

@@ -0,0 +1,58 @@
+/*
+ * Copyright (c) 2024, 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.  Oracle designates this
+ * particular file as subject to the "Classpath" exception as provided
+ * by Oracle in the LICENSE file that accompanied this code.
+ *
+ * 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.
+ */
+package jdk.graal.compiler.replacements.test;
+
+import org.junit.Test;
+
+public class HotSpotReflectionGetCallerClassTest extends MethodSubstitutionTest {
+    @Test
+    public void regressionTest() throws Exception {
+        test("getInstance");
+    }
+
+    // Replicates the code pattern from sun.net.ext.ExtendedSocketOptions.getInstance
+    // while avoiding a dependency on that class.
+    public static HotSpotReflectionGetCallerClassTest getInstance() {
+        HotSpotReflectionGetCallerClassTest ext = instance;
+        if (ext != null) {
+            return ext;
+        }
+        try {
+            Class.forName("jdk.graal.compiler.replacements.test.HotSpotReflectionGetCallerClassTest");
+            ext = instance;
+        } catch (ClassNotFoundException e) {
+            synchronized (HotSpotReflectionGetCallerClassTest.class) {
+                ext = instance;
+                if (ext != null) {
+                    return ext;
+                }
+                ext = instance = new HotSpotReflectionGetCallerClassTest();
+            }
+        }
+        return ext;
+    }
+
+    private static HotSpotReflectionGetCallerClassTest instance;
+}

compiler/src/jdk.graal.compiler/src/jdk/graal/compiler/phases/common/CanonicalizerPhase.java

@@ -678,10 +678,19 @@ private static boolean performReplacement(final Node node, Node newCanonical, To
                         node.replaceAtUsages(null);
                         GraphUtil.unlinkAndKillExceptionEdge(withException);
                         GraphUtil.killWithUnusedFloatingInputs(withException);
-                    } else if (canonical instanceof FloatingNode) {
+                    } else if (canonical instanceof FloatingNode floating) {
                         // case 4
-                        withException.killExceptionEdge();
-                        graph.replaceSplitWithFloating(withException, (FloatingNode) canonical, withException.next());
+                        /*
+                         * In corner cases it is possible for the killing of the exception edge to
+                         * trigger the killing of the replacement node. We therefore wait to kill
+                         * the exception edge until after replacing the WithException node.
+                         */
+                        var exceptionEdge = withException.exceptionEdge();
+                        withException.setExceptionEdge(null);
+                        graph.replaceSplitWithFloating(withException, floating, withException.next());
+                        if (exceptionEdge != null) {
+                            GraphUtil.killCFG(exceptionEdge);
+                        }
                     } else {
                         assert canonical instanceof FixedNode : Assertions.errorMessage(canonical);
                         if (canonical.predecessor() == null) {