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24 
25 #ifndef SHARE_RUNTIME_STUBCODEGENERATOR_HPP
26 #define SHARE_RUNTIME_STUBCODEGENERATOR_HPP
27 
28 #include "asm/assembler.hpp"
29 #include "memory/allocation.hpp"
30 
31 // All the basic framework for stub code generation/debugging/printing.
32 
33 
34 // A StubCodeDesc describes a piece of generated code (usually stubs).
35 // This information is mainly useful for debugging and printing.
36 // Currently, code descriptors are simply chained in a linked list,
37 // this may have to change if searching becomes too slow.
38 
39 class StubCodeDesc: public CHeapObj<mtCode> {
40  private:
41   static StubCodeDesc* _list;                  // the list of all descriptors
42   static bool          _frozen;                // determines whether _list modifications are allowed
43 
44   StubCodeDesc*        _next;                  // the next element in the linked list
45   const char*          _group;                 // the group to which the stub code belongs
46   const char*          _name;                  // the name assigned to the stub code
47   address              _begin;                 // points to the first byte of the stub code    (included)
48   address              _end;                   // points to the first byte after the stub code (excluded)
49 
set_end(address end)50   void set_end(address end) {
51     assert(_begin <= end, "begin & end not properly ordered");
52     _end = end;
53   }
54 
set_begin(address begin)55   void set_begin(address begin) {
56     assert(begin >= _begin, "begin may not decrease");
57     assert(_end == NULL || begin <= _end, "begin & end not properly ordered");
58     _begin = begin;
59   }
60 
61   friend class StubCodeMark;
62   friend class StubCodeGenerator;
63 
64  public:
first()65   static StubCodeDesc* first() { return _list; }
next(StubCodeDesc * desc)66   static StubCodeDesc* next(StubCodeDesc* desc)  { return desc->_next; }
67 
68   static StubCodeDesc* desc_for(address pc);     // returns the code descriptor for the code containing pc or NULL
69   static const char*   name_for(address pc);     // returns the name of the code containing pc or NULL
70 
StubCodeDesc(const char * group,const char * name,address begin,address end=NULL)71   StubCodeDesc(const char* group, const char* name, address begin, address end = NULL) {
72     assert(!_frozen, "no modifications allowed");
73     assert(name != NULL, "no name specified");
74     _next           = _list;
75     _group          = group;
76     _name           = name;
77     _begin          = begin;
78     _end            = end;
79     _list           = this;
80   };
81 
82   static void freeze();
83 
group() const84   const char* group() const                      { return _group; }
name() const85   const char* name() const                       { return _name; }
begin() const86   address     begin() const                      { return _begin; }
end() const87   address     end() const                        { return _end; }
size_in_bytes() const88   int         size_in_bytes() const              { return _end - _begin; }
contains(address pc) const89   bool        contains(address pc) const         { return _begin <= pc && pc < _end; }
90   void        print_on(outputStream* st) const;
91   void        print() const;
92 };
93 
94 // The base class for all stub-generating code generators.
95 // Provides utility functions.
96 
97 class StubCodeGenerator: public StackObj {
98  private:
99   bool _print_code;
100 
101  protected:
102   MacroAssembler*  _masm;
103 
104  public:
105   StubCodeGenerator(CodeBuffer* code, bool print_code = false);
106   ~StubCodeGenerator();
107 
assembler() const108   MacroAssembler* assembler() const              { return _masm; }
109 
110   virtual void stub_prolog(StubCodeDesc* cdesc); // called by StubCodeMark constructor
111   virtual void stub_epilog(StubCodeDesc* cdesc); // called by StubCodeMark destructor
112 };
113 
114 
115 // Stack-allocated helper class used to associate a stub code with a name.
116 // All stub code generating functions that use a StubCodeMark will be registered
117 // in the global StubCodeDesc list and the generated stub code can be identified
118 // later via an address pointing into it.
119 
120 class StubCodeMark: public StackObj {
121  private:
122   StubCodeGenerator* _cgen;
123   StubCodeDesc*      _cdesc;
124 
125  public:
126   StubCodeMark(StubCodeGenerator* cgen, const char* group, const char* name);
127   ~StubCodeMark();
128 
129 };
130 
131 #endif // SHARE_RUNTIME_STUBCODEGENERATOR_HPP
132