src/hotspot/share/runtime/javaFrameAnchor.hpp
changeset 47216 71c04702a3d5
parent 40010 e32d5e545789
child 49364 601146c66cad
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/hotspot/share/runtime/javaFrameAnchor.hpp	Tue Sep 12 19:03:39 2017 +0200
@@ -0,0 +1,96 @@
+/*
+ * Copyright (c) 2002, 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.
+ *
+ */
+
+#ifndef SHARE_VM_RUNTIME_JAVAFRAMEANCHOR_HPP
+#define SHARE_VM_RUNTIME_JAVAFRAMEANCHOR_HPP
+
+#include "runtime/orderAccess.inline.hpp"
+#include "utilities/globalDefinitions.hpp"
+#include "utilities/macros.hpp"
+
+//
+// An object for encapsulating the machine/os dependent part of a JavaThread frame state
+//
+class JavaThread;
+
+class JavaFrameAnchor VALUE_OBJ_CLASS_SPEC {
+// Too many friends...
+friend class CallNativeDirectNode;
+friend class OptoRuntime;
+friend class Runtime1;
+friend class StubAssembler;
+friend class CallRuntimeDirectNode;
+friend class MacroAssembler;
+friend class LIR_Assembler;
+friend class GraphKit;
+friend class StubGenerator;
+friend class JavaThread;
+friend class frame;
+friend class VMStructs;
+friend class JVMCIVMStructs;
+friend class BytecodeInterpreter;
+friend class JavaCallWrapper;
+
+ private:
+  //
+  // Whenever _last_Java_sp != NULL other anchor fields MUST be valid!
+  // The stack may not be walkable [check with walkable() ] but the values must be valid.
+  // The profiler apparently depends on this.
+  //
+  intptr_t* volatile _last_Java_sp;
+
+  // Whenever we call from Java to native we can not be assured that the return
+  // address that composes the last_Java_frame will be in an accessible location
+  // so calls from Java to native store that pc (or one good enough to locate
+  // the oopmap) in the frame anchor. Since the frames that call from Java to
+  // native are never deoptimized we never need to patch the pc and so this
+  // is acceptable.
+  volatile  address _last_Java_pc;
+
+  // tells whether the last Java frame is set
+  // It is important that when last_Java_sp != NULL that the rest of the frame
+  // anchor (including platform specific) all be valid.
+
+  bool has_last_Java_frame() const                   { return _last_Java_sp != NULL; }
+  // This is very dangerous unless sp == NULL
+  // Invalidate the anchor so that has_last_frame is false
+  // and no one should look at the other fields.
+  void zap(void)                                     { _last_Java_sp = NULL; }
+
+#include CPU_HEADER(javaFrameAnchor)
+
+public:
+  JavaFrameAnchor()                              { clear(); }
+  JavaFrameAnchor(JavaFrameAnchor *src)          { copy(src); }
+
+  void set_last_Java_pc(address pc)              { _last_Java_pc = pc; }
+
+  // Assembly stub generation helpers
+
+  static ByteSize last_Java_sp_offset()          { return byte_offset_of(JavaFrameAnchor, _last_Java_sp); }
+  static ByteSize last_Java_pc_offset()          { return byte_offset_of(JavaFrameAnchor, _last_Java_pc); }
+
+};
+
+#endif // SHARE_VM_RUNTIME_JAVAFRAMEANCHOR_HPP