--- /dev/null	2021-01-19 17:38:25.908523431 +0000
+++ new/src/cpu/aarch64/vm/metaspaceShared_aarch64.cpp	2021-01-25 19:31:50.874625070 +0000
@@ -0,0 +1,108 @@
+/*
+ * Copyright (c) 2013, Red Hat Inc.
+ * Copyright (c) 2004, 2012, 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.
+ *
+ */
+
+#include "precompiled.hpp"
+#include "asm/macroAssembler.hpp"
+#include "memory/metaspaceShared.hpp"
+
+// Generate the self-patching vtable method:
+//
+// This method will be called (as any other Klass virtual method) with
+// the Klass itself as the first argument.  Example:
+//
+//      oop obj;
+//      int size = obj->klass()->oop_size(this);
+//
+// for which the virtual method call is Klass::oop_size();
+//
+// The dummy method is called with the Klass object as the first
+// operand, and an object as the second argument.
+//
+
+//=====================================================================
+
+// All of the dummy methods in the vtable are essentially identical,
+// differing only by an ordinal constant, and they bear no relationship
+// to the original method which the caller intended. Also, there needs
+// to be 'vtbl_list_size' instances of the vtable in order to
+// differentiate between the 'vtable_list_size' original Klass objects.
+
+#define __ masm->
+
+extern "C" {
+  void aarch64_prolog(void);
+}
+
+void MetaspaceShared::generate_vtable_methods(void** vtbl_list,
+                                                   void** vtable,
+                                                   char** md_top,
+                                                   char* md_end,
+                                                   char** mc_top,
+                                                   char* mc_end) {
+
+  intptr_t vtable_bytes = (num_virtuals * vtbl_list_size) * sizeof(void*);
+  *(intptr_t *)(*md_top) = vtable_bytes;
+  *md_top += sizeof(intptr_t);
+  void** dummy_vtable = (void**)*md_top;
+  *vtable = dummy_vtable;
+  *md_top += vtable_bytes;
+
+  // Get ready to generate dummy methods.
+
+  CodeBuffer cb((unsigned char*)*mc_top, mc_end - *mc_top);
+  MacroAssembler* masm = new MacroAssembler(&cb);
+
+  Label common_code;
+  for (int i = 0; i < vtbl_list_size; ++i) {
+    for (int j = 0; j < num_virtuals; ++j) {
+      dummy_vtable[num_virtuals * i + j] = (void*)masm->pc();
+
+      // We're called directly from C code.
+      // Load rscratch1 with a value indicating vtable/offset pair.
+      // -- bits[ 7..0]  (8 bits) which virtual method in table?
+      // -- bits[12..8]  (5 bits) which virtual method table?
+      __ mov(rscratch1, (i << 8) + j);
+      __ b(common_code);
+    }
+  }
+
+  __ bind(common_code);
+
+  Register tmp0 = r10, tmp1 = r11;       // AAPCS64 temporary registers
+  __ enter();
+  __ lsr(tmp0, rscratch1, 8);            // isolate vtable identifier.
+  __ mov(tmp1, (address)vtbl_list);      // address of list of vtable pointers.
+  __ ldr(tmp1, Address(tmp1, tmp0, Address::lsl(LogBytesPerWord))); // get correct vtable pointer.
+  __ str(tmp1, Address(c_rarg0));        // update vtable pointer in obj.
+  __ add(rscratch1, tmp1, rscratch1, ext::uxtb, LogBytesPerWord); // address of real method pointer.
+  __ ldr(rscratch1, Address(rscratch1)); // get real method pointer.
+  __ blr(rscratch1);                     // jump to the real method.
+  __ leave();
+  __ ret(lr);
+
+  *mc_top = (char*)__ pc();
+}
+