--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/hotspot/share/utilities/nativeCallStack.cpp	Tue Sep 12 19:03:39 2017 +0200
@@ -0,0 +1,122 @@
+/*
+ * Copyright (c) 2014, 2016, 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 "runtime/os.hpp"
+#include "utilities/globalDefinitions.hpp"
+#include "utilities/nativeCallStack.hpp"
+
+const NativeCallStack NativeCallStack::EMPTY_STACK(0, false);
+
+NativeCallStack::NativeCallStack(int toSkip, bool fillStack) :
+  _hash_value(0) {
+
+  if (fillStack) {
+    // We need to skip the NativeCallStack::NativeCallStack frame if a tail call is NOT used
+    // to call os::get_native_stack. A tail call is used if _NMT_NOINLINE_ is not defined
+    // (which means this is not a slowdebug build), and we are on 64-bit (except Windows).
+    // This is not necessarily a rule, but what has been obvserved to date.
+#define TAIL_CALL (!defined(_NMT_NOINLINE_) && !defined(WINDOWS) && defined(_LP64))
+#if !TAIL_CALL
+    toSkip++;
+#if (defined(_NMT_NOINLINE_) && defined(BSD) && defined(_LP64))
+    // Mac OS X slowdebug builds have this odd behavior where NativeCallStack::NativeCallStack
+    // appears as two frames, so we need to skip an extra frame.
+    toSkip++;
+#endif
+#endif
+    os::get_native_stack(_stack, NMT_TrackingStackDepth, toSkip);
+  } else {
+    for (int index = 0; index < NMT_TrackingStackDepth; index ++) {
+      _stack[index] = NULL;
+    }
+  }
+}
+
+NativeCallStack::NativeCallStack(address* pc, int frameCount) {
+  int frameToCopy = (frameCount < NMT_TrackingStackDepth) ?
+    frameCount : NMT_TrackingStackDepth;
+  int index;
+  for (index = 0; index < frameToCopy; index ++) {
+    _stack[index] = pc[index];
+  }
+  for (; index < NMT_TrackingStackDepth; index ++) {
+    _stack[index] = NULL;
+  }
+  _hash_value = 0;
+}
+
+// number of stack frames captured
+int NativeCallStack::frames() const {
+  int index;
+  for (index = 0; index < NMT_TrackingStackDepth; index ++) {
+    if (_stack[index] == NULL) {
+      break;
+    }
+  }
+  return index;
+}
+
+// Hash code. Any better algorithm?
+unsigned int NativeCallStack::hash() const {
+  uintptr_t hash_val = _hash_value;
+  if (hash_val == 0) {
+    for (int index = 0; index < NMT_TrackingStackDepth; index++) {
+      if (_stack[index] == NULL) break;
+      hash_val += (uintptr_t)_stack[index];
+    }
+
+    NativeCallStack* p = const_cast<NativeCallStack*>(this);
+    p->_hash_value = (unsigned int)(hash_val & 0xFFFFFFFF);
+  }
+  return _hash_value;
+}
+
+void NativeCallStack::print_on(outputStream* out) const {
+  print_on(out, 0);
+}
+
+// Decode and print this call path
+void NativeCallStack::print_on(outputStream* out, int indent) const {
+  address pc;
+  char    buf[1024];
+  int     offset;
+  if (is_empty()) {
+    for (int index = 0; index < indent; index ++) out->print(" ");
+    out->print("[BOOTSTRAP]");
+  } else {
+    for (int frame = 0; frame < NMT_TrackingStackDepth; frame ++) {
+      pc = get_frame(frame);
+      if (pc == NULL) break;
+      // Print indent
+      for (int index = 0; index < indent; index ++) out->print(" ");
+      if (os::dll_address_to_function_name(pc, buf, sizeof(buf), &offset)) {
+        out->print_cr("[" PTR_FORMAT "] %s+0x%x", p2i(pc), buf, offset);
+      } else {
+        out->print_cr("[" PTR_FORMAT "]", p2i(pc));
+      }
+    }
+  }
+}
+