8314275: Incorrect stepping in switch

Backport-of: e3dc6a7a28c4f049eb234c5487fca6c54298aa31

Author: biboudis

src/jdk.compiler/share/classes/com/sun/tools/javac/jvm/Gen.java

@@ -1428,6 +1428,11 @@ private void handleSwitch(JCTree swtch, JCExpression selector, List<JCCase> case
                     code.put4(caseidx + 4, offsets[i]);
                 }
             }
+
+            if (swtch instanceof JCSwitchExpression) {
+                 // Emit line position for the end of a switch expression
+                 code.statBegin(TreeInfo.endPos(swtch));
+            }
         }
         code.endScopes(limit);
     }

test/langtools/tools/javac/classfiles/attributes/LineNumberTable/T8314275.java

@@ -0,0 +1,79 @@
+/*
+ * 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.
+ *
+ * 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 8314275
+ * @summary Tests a line number table attribute for switch expression
+ * @library /tools/lib /tools/javac/lib ../lib
+ * @enablePreview
+ * @modules jdk.compiler/com.sun.tools.javac.api
+ *          jdk.compiler/com.sun.tools.javac.main
+ *          jdk.compiler/com.sun.tools.javac.util
+ *          java.base/jdk.internal.classfile.impl
+ * @build toolbox.ToolBox InMemoryFileManager TestBase
+ * @build LineNumberTestBase TestCase
+ * @run main T8314275
+ */
+import java.util.List;
+public class T8314275 extends LineNumberTestBase {
+    public static void main(String[] args) throws Exception {
+        new T8314275().test();
+    }
+
+    public void test() throws Exception {
+        test(List.of(TEST_CASE));
+    }
+
+    private static final TestCase[] TEST_CASE = new TestCase[] {
+        new TestCase("""
+             public class T8314275Expression {                     // 1
+                 private static double multiply(Integer i) {       // 2
+                      double cr = 15;                              // 3
+                      cr = switch (i) {                            // 4
+                          case 1 -> cr * 1;                        // 5
+                          case 2 -> cr * 2;                        // 6
+                          default -> cr * 4;                       // 7
+                      };                                           // 8
+                      return cr;                                   // 9
+                  }                                                //10
+             }                                                     //11
+             """,
+            List.of(1, 3, 4, 5, 6, 7, 8, 9),
+            "T8314275Expression"),
+        new TestCase("""
+             public class T8314275Statement {                      // 1
+                 private static double multiply(Integer i) {       // 2
+                      double cr = 15;                              // 3
+                      switch (i) {                                 // 4
+                          case 1: cr *= 1; break;                  // 5
+                          case 2: cr *= 2; break;                  // 6
+                          default: cr *= 4;                        // 7
+                      };                                           // 8
+                      return cr;                                   // 9
+                  }                                                //10
+             }                                                     //11
+             """,
+                List.of(1, 3, 4, 5, 6, 7, 9),
+                "T8314275Statement")
+    };
+}