8317636: Improve heap walking API tests to verify correctness of fiel…

…d indexes

Reviewed-by: cjplummer, sspitsyn

test/hotspot/jtreg/serviceability/jvmti/FollowReferences/FieldIndices/FieldIndicesTest.java

@@ -0,0 +1,128 @@
+/*
+ * 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 8317636
+ * @summary The test verifies heap walking API (FollowReferences) reports
+ *     field indeces in correct order (as described by jvmtiHeapReferenceInfoField spec).
+ *     For simplification only primitive field callback is tested
+ *     and all fields in the test classes are 'int'.
+ *     Field IDs are not reported to the callback, so the test uses field values
+ *     to distinguish between fields, so all field values in the test classes should be unique.
+ * @run main/othervm/native -agentlib:FieldIndicesTest FieldIndicesTest
+ */
+
+import java.lang.ref.Reference;
+
+// Test class hierarchy is based on the example described in the spec.
+// Extra fields added to improve coverage.
+interface I0 {
+    int p = 10;
+    // extra fields
+    public int p5 = 11;
+    int p6 = 12;
+    public int p1 = 13;
+}
+
+interface I1 extends I0 {
+    int x = 20;
+    // extra fields
+    int x1 = 21;
+    public int x2 = 22;
+}
+
+interface I2 extends I0 {
+    int y = 30;
+    // extra fields
+    int y9 = 31;
+    public int y4 = 32;
+    public int y3 = 33;
+}
+
+class C1 implements I1 {
+    public static int a = 40;
+    private int b = 41;
+    // extra fields
+    private int a1 = 42;
+    protected static int b7 = 43;
+    static int b2 = 44;
+    final protected int a3 = 45;
+    static int a2 = 46;
+    public int b1 = 47;
+}
+
+class C2 extends C1 implements I2 {
+    static int q = 60;
+    final int r = 61;
+    // extra fields
+    private int q11 = 61;
+    final static int q9 = 62;
+    static int q2 = 63;
+    final protected int r3 = 64;
+    public int r7 = 65;
+}
+
+public class FieldIndicesTest {
+    static {
+        System.loadLibrary("FieldIndicesTest");
+    }
+
+    private static native void prepare(Object testObject);
+
+    private static native void test(Object rootObject);
+
+    private static native boolean testFailed();
+
+    private static void prepare(String name, Object testObject) {
+        System.out.println(">>prepare(" + name + ")");
+        prepare(testObject);
+        System.out.println("<<prepare(" + name + ")");
+        System.out.println();
+    }
+
+    private static void test(String name, Object rootObject) {
+        System.out.println(">>test(" + name + ")");
+        test(rootObject);
+        System.out.println("<<test(" + name + ")");
+        System.out.println();
+    }
+
+    public static void main(String argv[]) {
+        C1 obj1 = new C1();
+        C2 obj2 = new C2();
+
+        prepare("obj1", obj1);
+        prepare("obj2", obj2);
+
+        test("obj1", obj1);
+        test("obj2", obj2);
+
+        Reference.reachabilityFence(obj1);
+        Reference.reachabilityFence(obj2);
+
+        if (testFailed()) {
+            throw new RuntimeException("Test failed. See log for details");
+        }
+    }
+}