1 /*
   2  * Copyright (c) 2015, 2016 Oracle and/or its affiliates. All rights reserved.
   3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   4  *
   5  * This code is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License version 2 only, as
   7  * published by the Free Software Foundation.
   8  *
   9  * This code is distributed in the hope that it will be useful, but WITHOUT
  10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  12  * version 2 for more details (a copy is included in the LICENSE file that
  13  * accompanied this code).
  14  *
  15  * You should have received a copy of the GNU General Public License version
  16  * 2 along with this work; if not, write to the Free Software Foundation,
  17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  18  *
  19  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  20  * or visit www.oracle.com if you need additional information or have any
  21  * questions.
  22  *
  23  */
  24 
  25 
  26 #ifndef SHARE_VM_PRIMS_STACKWALK_HPP
  27 #define SHARE_VM_PRIMS_STACKWALK_HPP
  28 
  29 #include "oops/oop.hpp"
  30 #include "runtime/vframe.hpp"
  31 
  32 //
  33 // JavaFrameStream is used by StackWalker to iterate through Java stack frames
  34 // on the given JavaThread.
  35 //
  36 class JavaFrameStream : public StackObj {
  37 private:
  38   enum {
  39     magic_pos = 0
  40   };
  41 
  42   JavaThread*           _thread;
  43   javaVFrame*           _jvf;
  44   jlong                 _anchor;
  45 public:
  46   JavaFrameStream(JavaThread* thread, RegisterMap* rm)
  47     : _thread(thread), _anchor(0L) {
  48     _jvf = _thread->last_java_vframe(rm);
  49   }
  50 
  51   javaVFrame*     java_frame()        { return _jvf; }
  52   void            next()              { _jvf = _jvf->java_sender(); }
  53   bool            at_end()            { return _jvf == NULL; }
  54 
  55   Method* method()                    { return _jvf->method(); }
  56   int bci()                           { return _jvf->bci(); }
  57 
  58   void setup_magic_on_entry(objArrayHandle frames_array);
  59   bool check_magic(objArrayHandle frames_array);
  60   bool cleanup_magic_on_exit(objArrayHandle frames_array);
  61 
  62   bool is_valid_in(Thread* thread, objArrayHandle frames_array) {
  63     return (_thread == thread && check_magic(frames_array));
  64   }
  65 
  66   jlong address_value() {
  67     return (jlong) castable_address(this);
  68   }
  69 
  70   static JavaFrameStream* from_current(JavaThread* thread, jlong magic, objArrayHandle frames_array);
  71 };
  72 
  73 class StackWalk : public AllStatic {
  74 private:
  75   static int fill_in_frames(jlong mode, JavaFrameStream& stream,
  76                             int max_nframes, int start_index,
  77                             objArrayHandle frames_array,
  78                             int& end_index, TRAPS);
  79 
  80   static void fill_stackframe(Handle stackFrame, const methodHandle& method, int bci);
  81 
  82   static void fill_live_stackframe(Handle stackFrame, const methodHandle& method, int bci,
  83                                    javaVFrame* jvf, TRAPS);
  84 
  85   static inline bool skip_hidden_frames(int mode) {
  86     return (mode & JVM_STACKWALK_SHOW_HIDDEN_FRAMES) == 0;
  87   }
  88   static inline bool need_method_info(int mode) {
  89     return (mode & JVM_STACKWALK_FILL_CLASS_REFS_ONLY) == 0;
  90   }
  91   static inline bool live_frame_info(int mode) {
  92     return (mode & JVM_STACKWALK_FILL_LIVE_STACK_FRAMES) != 0;
  93   }
  94 
  95 public:
  96   static inline bool use_frames_array(int mode) {
  97     return (mode & JVM_STACKWALK_FILL_CLASS_REFS_ONLY) == 0;
  98   }
  99   static oop walk(Handle stackStream, jlong mode,
 100                   int skip_frames, int frame_count, int start_index,
 101                   objArrayHandle frames_array,
 102                   TRAPS);
 103 
 104   static jint moreFrames(Handle stackStream, jlong mode, jlong magic,
 105                          int frame_count, int start_index,
 106                          objArrayHandle frames_array,
 107                          TRAPS);
 108 };
 109 #endif // SHARE_VM_PRIMS_STACKWALK_HPP