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24 
25 #ifndef SHARE_VM_CODE_SCOPEDESC_HPP
26 #define SHARE_VM_CODE_SCOPEDESC_HPP
27 
28 #include "code/debugInfo.hpp"
29 #include "code/pcDesc.hpp"
30 #include "oops/method.hpp"
31 #include "utilities/growableArray.hpp"
32 
33 // SimpleScopeDesc is used when all you need to extract from
34 // a given pc,nmethod pair is a Method* and a bci. This is
35 // quite a bit faster than allocating a full ScopeDesc, but
36 // very limited in abilities.
37 
38 class SimpleScopeDesc : public StackObj {
39  private:
40   Method* _method;
41   int _bci;
42 
43  public:
SimpleScopeDesc(nmethod * code,address pc)44   SimpleScopeDesc(nmethod* code,address pc) {
45     PcDesc* pc_desc = code->pc_desc_at(pc);
46     assert(pc_desc != NULL, "Must be able to find matching PcDesc");
47     DebugInfoReadStream buffer(code, pc_desc->scope_decode_offset());
48     int ignore_sender = buffer.read_int();
49     _method           = buffer.read_method();
50     _bci              = buffer.read_bci();
51   }
52 
method()53   Method* method() { return _method; }
bci()54   int bci() { return _bci; }
55 };
56 
57 // ScopeDescs contain the information that makes source-level debugging of
58 // nmethods possible; each scopeDesc describes a method activation
59 
60 class ScopeDesc : public ResourceObj {
61  public:
62   // Constructor
63   ScopeDesc(const nmethod* code, int decode_offset, int obj_decode_offset, bool reexecute, bool return_oop);
64 
65   // Calls above, giving default value of "serialized_null" to the
66   // "obj_decode_offset" argument.  (We don't use a default argument to
67   // avoid a .hpp-.hpp dependency.)
68   ScopeDesc(const nmethod* code, int decode_offset, bool reexecute, bool return_oop);
69 
70   // JVM state
method() const71   Method* method()      const { return _method; }
bci() const72   int          bci()      const { return _bci;    }
should_reexecute() const73   bool should_reexecute() const { return _reexecute; }
return_oop() const74   bool return_oop()       const { return _return_oop; }
75 
76   GrowableArray<ScopeValue*>*   locals();
77   GrowableArray<ScopeValue*>*   expressions();
78   GrowableArray<MonitorValue*>* monitors();
79   GrowableArray<ScopeValue*>*   objects();
80 
81   // Stack walking, returns NULL if this is the outer most scope.
82   ScopeDesc* sender() const;
83 
84   // Returns where the scope was decoded
decode_offset() const85   int decode_offset() const { return _decode_offset; }
86 
87   // Tells whether sender() returns NULL
88   bool is_top() const;
89   // Tells whether sd is equal to this
90   bool is_equal(ScopeDesc* sd) const;
91 
92  private:
93   // Alternative constructor
94   ScopeDesc(const ScopeDesc* parent);
95 
96   // JVM state
97   Method*       _method;
98   int           _bci;
99   bool          _reexecute;
100   bool          _return_oop;
101 
102   // Decoding offsets
103   int _decode_offset;
104   int _sender_decode_offset;
105   int _locals_decode_offset;
106   int _expressions_decode_offset;
107   int _monitors_decode_offset;
108 
109   // Object pool
110   GrowableArray<ScopeValue*>* _objects;
111 
112   // Nmethod information
113   const nmethod* _code;
114 
115   // Decoding operations
116   void decode_body();
117   GrowableArray<ScopeValue*>* decode_scope_values(int decode_offset);
118   GrowableArray<MonitorValue*>* decode_monitor_values(int decode_offset);
119   GrowableArray<ScopeValue*>* decode_object_values(int decode_offset);
120 
121   DebugInfoReadStream* stream_at(int decode_offset) const;
122 
123 
124  public:
125   // Verification
126   void verify();
127 
128 #ifndef PRODUCT
129  public:
130   // Printing support
131   void print_on(outputStream* st) const;
132   void print_on(outputStream* st, PcDesc* pd) const;
133   void print_value_on(outputStream* st) const;
134 #endif
135 };
136 
137 #endif // SHARE_VM_CODE_SCOPEDESC_HPP
138