--- /dev/null	2018-12-03 11:58:50.256341286 +0100
+++ new/test/hotspot/jtreg/gc/shenandoah/jvmti/libTestHeapDump.c	2018-12-03 17:49:24.300572920 +0100
@@ -0,0 +1,130 @@
+/*
+ * Copyright (c) 2017, 2018, Red Hat, Inc. All rights reserved.
+ *
+ * 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.
+ *
+ */
+
+#include <stdio.h>
+#include <string.h>
+#include "jvmti.h"
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+#ifndef JNI_ENV_ARG
+
+#ifdef __cplusplus
+#define JNI_ENV_ARG(x, y) y
+#define JNI_ENV_PTR(x) x
+#else
+#define JNI_ENV_ARG(x,y) x, y
+#define JNI_ENV_PTR(x) (*x)
+#endif
+
+#endif
+
+#define TranslateError(err) "JVMTI error"
+
+#define PASSED 0
+#define FAILED 2
+
+static const char *EXC_CNAME = "java/lang/Exception";
+
+static jvmtiEnv *jvmti = NULL;
+static jint result = PASSED;
+
+static jint Agent_Initialize(JavaVM *jvm, char *options, void *reserved);
+
+JNIEXPORT
+jint JNICALL Agent_OnLoad(JavaVM *jvm, char *options, void *reserved) {
+    return Agent_Initialize(jvm, options, reserved);
+}
+
+JNIEXPORT
+jint JNICALL Agent_OnAttach(JavaVM *jvm, char *options, void *reserved) {
+    return Agent_Initialize(jvm, options, reserved);
+}
+
+JNIEXPORT
+jint JNICALL JNI_OnLoad(JavaVM *jvm, void *reserved) {
+    return JNI_VERSION_1_8;
+}
+
+static
+jint Agent_Initialize(JavaVM *jvm, char *options, void *reserved) {
+    jvmtiCapabilities capabilities;
+    jint res = JNI_ENV_PTR(jvm)->GetEnv(JNI_ENV_ARG(jvm, (void **) &jvmti),
+                                        JVMTI_VERSION_9);
+    if (res != JNI_OK || jvmti == NULL) {
+        printf("    Error: wrong result of a valid call to GetEnv!\n");
+        return JNI_ERR;
+    }
+
+    (void)memset(&capabilities, 0, sizeof(capabilities));
+    capabilities.can_tag_objects = 1;
+    capabilities.can_generate_garbage_collection_events = 1;
+    (*jvmti)->AddCapabilities(jvmti, &capabilities);
+
+    return JNI_OK;
+}
+
+static
+void throw_exc(JNIEnv *env, char *msg) {
+    jclass exc_class = JNI_ENV_PTR(env)->FindClass(JNI_ENV_ARG(env, EXC_CNAME));
+    jint rt = JNI_OK;
+
+    if (exc_class == NULL) {
+        printf("throw_exc: Error in FindClass(env, %s)\n", EXC_CNAME);
+        return;
+    }
+    rt = JNI_ENV_PTR(env)->ThrowNew(JNI_ENV_ARG(env, exc_class), msg);
+    if (rt == JNI_ERR) {
+        printf("throw_exc: Error in JNI ThrowNew(env, %s)\n", msg);
+    }
+}
+
+static jint JNICALL heap_iter_callback(jlong class_tag,
+                               jlong size,
+                               jlong* tag_ptr,
+                               jint length,
+                               void* user_data) {
+  (*((jint*)(user_data)))++;
+  return JVMTI_VISIT_OBJECTS;
+}
+
+JNIEXPORT jint JNICALL
+Java_TestHeapDump_heapdump(JNIEnv *env, jclass cls, jclass filter_cls) {
+    jvmtiHeapCallbacks callbacks;
+    jint totalCount = 0;
+    if (jvmti == NULL) {
+        throw_exc(env, "JVMTI client was not properly loaded!\n");
+        return 0;
+    }
+
+    (void)memset(&callbacks, 0, sizeof(callbacks));
+    callbacks.heap_iteration_callback = &heap_iter_callback;
+    (*jvmti)->IterateThroughHeap(jvmti, 0, filter_cls, &callbacks, (const void *)&totalCount);
+    return totalCount;
+}
+
+#ifdef __cplusplus
+}
+#endif