pcDesc.hpp revision 1472:c18cbe5936b8 
1/*
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3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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7 * published by the Free Software Foundation.
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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
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14 *
15 * You should have received a copy of the GNU General Public License version
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24
25// PcDescs map a physical PC (given as offset from start of nmethod) to
26// the corresponding source scope and byte code index.
27
28class nmethod;
29
30class PcDesc VALUE_OBJ_CLASS_SPEC {
31  friend class VMStructs;
32 private:
33  int _pc_offset;           // offset from start of nmethod
34  int _scope_decode_offset; // offset for scope in nmethod
35  int _obj_decode_offset;
36
37  union PcDescFlags {
38    int word;
39    struct {
40      unsigned int reexecute: 1;
41      unsigned int is_method_handle_invoke: 1;
42      unsigned int return_oop: 1;
43    } bits;
44    bool operator ==(const PcDescFlags& other) { return word == other.word; }
45  } _flags;
46
47 public:
48  int pc_offset() const           { return _pc_offset;   }
49  int scope_decode_offset() const { return _scope_decode_offset; }
50  int obj_decode_offset() const   { return _obj_decode_offset; }
51
52  void set_pc_offset(int x)           { _pc_offset           = x; }
53  void set_scope_decode_offset(int x) { _scope_decode_offset = x; }
54  void set_obj_decode_offset(int x)   { _obj_decode_offset   = x; }
55
56  // Constructor (only used for static in nmethod.cpp)
57  // Also used by ScopeDesc::sender()]
58  PcDesc(int pc_offset, int scope_decode_offset, int obj_decode_offset);
59
60  enum {
61    // upper and lower exclusive limits real offsets:
62    lower_offset_limit = -1,
63    upper_offset_limit = (unsigned int)-1 >> 1
64  };
65
66  // Flags
67  bool     should_reexecute()              const { return _flags.bits.reexecute; }
68  void set_should_reexecute(bool z)              { _flags.bits.reexecute = z;    }
69
70  // Does pd refer to the same information as pd?
71  bool is_same_info(const PcDesc* pd) {
72    return _scope_decode_offset == pd->_scope_decode_offset &&
73      _obj_decode_offset == pd->_obj_decode_offset &&
74      _flags == pd->_flags;
75  }
76
77  bool     is_method_handle_invoke()       const { return _flags.bits.is_method_handle_invoke;     }
78  void set_is_method_handle_invoke(bool z)       {        _flags.bits.is_method_handle_invoke = z; }
79
80  bool     return_oop()                    const { return _flags.bits.return_oop;     }
81  void set_return_oop(bool z)                    {        _flags.bits.return_oop = z; }
82
83  // Returns the real pc
84  address real_pc(const nmethod* code) const;
85
86  void print(nmethod* code);
87  bool verify(nmethod* code);
88};
89