src/share/vm/code/stubs.hpp

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rev 4202 : 8008555: Debugging code in compiled method sometimes leaks memory
Summary: support for strings that have same life-time as code that uses them.
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  56 //
  57 //                ________
  58 // stub       -->|        | <--+
  59 //               |  data  |    |
  60 //               |________|    |
  61 // code_begin -->|        |    |
  62 //               |        |    |
  63 //               |  code  |    | size
  64 //               |        |    |
  65 //               |________|    |
  66 // code_end   -->|        |    |
  67 //               |  data  |    |
  68 //               |________|    |
  69 //                          <--+
  70 
  71 
  72 class Stub VALUE_OBJ_CLASS_SPEC {
  73  public:
  74   // Initialization/finalization
  75   void    initialize(int size,
  76                      CodeComments& comments)     { ShouldNotCallThis(); }                // called to initialize/specify the stub's size
  77   void    finalize()                             { ShouldNotCallThis(); }                // called before the stub is deallocated
  78 
  79   // General info/converters
  80   int     size() const                           { ShouldNotCallThis(); return 0; }      // must return the size provided by initialize
  81   static  int code_size_to_size(int code_size)   { ShouldNotCallThis(); return 0; }      // computes the size given the code size
  82 
  83   // Code info
  84   address code_begin() const                     { ShouldNotCallThis(); return NULL; }   // points to the first byte of    the code
  85   address code_end() const                       { ShouldNotCallThis(); return NULL; }   // points to the first byte after the code
  86 
  87   // Debugging
  88   void    verify()                               { ShouldNotCallThis(); }                // verifies the Stub
  89   void    print()                                { ShouldNotCallThis(); }                // prints some information about the stub
  90 };
  91 
  92 
  93 // A stub interface defines the interface between a stub queue
  94 // and the stubs it queues. In order to avoid a vtable and
  95 // (and thus the extra word) in each stub, a concrete stub
  96 // interface object is created and associated with a stub
  97 // buffer which in turn uses the stub interface to interact
  98 // with its stubs.
  99 //
 100 // StubInterface serves as an abstract base class. A concrete
 101 // stub interface implementation is a subclass of StubInterface,
 102 // forwarding its virtual function calls to non-virtual calls
 103 // of the concrete stub (see also macro below). There's exactly
 104 // one stub interface instance required per stub queue.
 105 
 106 class StubInterface: public CHeapObj<mtCode> {
 107  public:
 108   // Initialization/finalization
 109   virtual void    initialize(Stub* self, int size,
 110                              CodeComments& comments)       = 0; // called after creation (called twice if allocated via (request, commit))
 111   virtual void    finalize(Stub* self)                     = 0; // called before deallocation
 112 
 113   // General info/converters
 114   virtual int     size(Stub* self) const                   = 0; // the total size of the stub in bytes (must be a multiple of CodeEntryAlignment)
 115   virtual int     code_size_to_size(int code_size) const   = 0; // computes the total stub size in bytes given the code size in bytes
 116 
 117   // Code info
 118   virtual address code_begin(Stub* self) const             = 0; // points to the first code byte
 119   virtual address code_end(Stub* self) const               = 0; // points to the first byte after the code
 120 
 121   // Debugging
 122   virtual void    verify(Stub* self)                       = 0; // verifies the stub
 123   virtual void    print(Stub* self)                        = 0; // prints information about the stub
 124 };
 125 
 126 
 127 // DEF_STUB_INTERFACE is used to create a concrete stub interface
 128 // class, forwarding stub interface calls to the corresponding
 129 // stub calls.
 130 
 131 #define DEF_STUB_INTERFACE(stub)                           \
 132   class stub##Interface: public StubInterface {            \
 133    private:                                                \
 134     static stub*    cast(Stub* self)                       { return (stub*)self; }                 \
 135                                                            \
 136    public:                                                 \
 137     /* Initialization/finalization */                      \
 138     virtual void    initialize(Stub* self, int size,       \
 139                                CodeComments& comments)     { cast(self)->initialize(size, comments); } \
 140     virtual void    finalize(Stub* self)                   { cast(self)->finalize(); }             \
 141                                                            \
 142     /* General info */                                     \
 143     virtual int     size(Stub* self) const                 { return cast(self)->size(); }          \
 144     virtual int     code_size_to_size(int code_size) const { return stub::code_size_to_size(code_size); } \
 145                                                            \
 146     /* Code info */                                        \
 147     virtual address code_begin(Stub* self) const           { return cast(self)->code_begin(); }    \
 148     virtual address code_end(Stub* self) const             { return cast(self)->code_end(); }      \
 149                                                            \
 150     /* Debugging */                                        \
 151     virtual void    verify(Stub* self)                     { cast(self)->verify(); }               \
 152     virtual void    print(Stub* self)                      { cast(self)->print(); }                \
 153   };
 154 
 155 
 156 // A StubQueue maintains a queue of stubs.
 157 // Note: All sizes (spaces) are given in bytes.
 158 
 159 class StubQueue: public CHeapObj<mtCode> {
 160   friend class VMStructs;
 161  private:
 162   StubInterface* _stub_interface;                // the interface prototype
 163   address        _stub_buffer;                   // where all stubs are stored
 164   int            _buffer_size;                   // the buffer size in bytes
 165   int            _buffer_limit;                  // the (byte) index of the actual buffer limit (_buffer_limit <= _buffer_size)
 166   int            _queue_begin;                   // the (byte) index of the first queue entry (word-aligned)
 167   int            _queue_end;                     // the (byte) index of the first entry after the queue (word-aligned)
 168   int            _number_of_stubs;               // the number of buffered stubs
 169   Mutex* const   _mutex;                         // the lock used for a (request, commit) transaction
 170 
 171   void  check_index(int i) const                 { assert(0 <= i && i < _buffer_limit && i % CodeEntryAlignment == 0, "illegal index"); }
 172   bool  is_contiguous() const                    { return _queue_begin <= _queue_end; }
 173   int   index_of(Stub* s) const                  { int i = (address)s - _stub_buffer; check_index(i); return i; }
 174   Stub* stub_at(int i) const                     { check_index(i); return (Stub*)(_stub_buffer + i); }
 175   Stub* current_stub() const                     { return stub_at(_queue_end); }
 176 
 177   // Stub functionality accessed via interface
 178   void  stub_initialize(Stub* s, int size,
 179                         CodeComments& comments)  { assert(size % CodeEntryAlignment == 0, "size not aligned"); _stub_interface->initialize(s, size, comments); }
 180   void  stub_finalize(Stub* s)                   { _stub_interface->finalize(s); }
 181   int   stub_size(Stub* s) const                 { return _stub_interface->size(s); }
 182   bool  stub_contains(Stub* s, address pc) const { return _stub_interface->code_begin(s) <= pc && pc < _stub_interface->code_end(s); }
 183   int   stub_code_size_to_size(int code_size) const { return _stub_interface->code_size_to_size(code_size); }
 184   void  stub_verify(Stub* s)                     { _stub_interface->verify(s); }
 185   void  stub_print(Stub* s)                      { _stub_interface->print(s); }
 186 
 187   static void register_queue(StubQueue*);
 188 
 189  public:
 190   StubQueue(StubInterface* stub_interface, int buffer_size, Mutex* lock,
 191             const char* name);
 192   ~StubQueue();
 193 
 194   // General queue info
 195   bool  is_empty() const                         { return _queue_begin == _queue_end; }
 196   int   total_space() const                      { return _buffer_size - 1; }
 197   int   available_space() const                  { int d = _queue_begin - _queue_end - 1; return d < 0 ? d + _buffer_size : d; }
 198   int   used_space() const                       { return total_space() - available_space(); }
 199   int   number_of_stubs() const                  { return _number_of_stubs; }
 200   bool  contains(address pc) const               { return _stub_buffer <= pc && pc < _stub_buffer + _buffer_limit; }
 201   Stub* stub_containing(address pc) const;
 202   address code_start() const                     { return _stub_buffer; }
 203   address code_end() const                       { return _stub_buffer + _buffer_limit; }
 204 
 205   // Stub allocation (atomic transactions)
 206   Stub* request_committed(int code_size);        // request a stub that provides exactly code_size space for code
 207   Stub* request(int requested_code_size);        // request a stub with a (maximum) code space - locks the queue
 208   void  commit (int committed_code_size,
 209                 CodeComments& comments);         // commit the previously requested stub - unlocks the queue
 210 
 211   // Stub deallocation
 212   void  remove_first();                          // remove the first stub in the queue
 213   void  remove_first(int n);                     // remove the first n stubs in the queue
 214   void  remove_all();                            // remove all stubs in the queue
 215 
 216   // Iteration
 217   static void queues_do(void f(StubQueue* s));   // call f with each StubQueue
 218   void  stubs_do(void f(Stub* s));               // call f with all stubs
 219   Stub* first() const                            { return number_of_stubs() > 0 ? stub_at(_queue_begin) : NULL; }
 220   Stub* next(Stub* s) const                      { int i = index_of(s) + stub_size(s);
 221                                                    if (i == _buffer_limit) i = 0;
 222                                                    return (i == _queue_end) ? NULL : stub_at(i);
 223                                                  }
 224 
 225   address stub_code_begin(Stub* s) const         { return _stub_interface->code_begin(s); }
 226   address stub_code_end(Stub* s) const           { return _stub_interface->code_end(s);   }
 227 
 228   // Debugging/printing
 229   void  verify();                                // verifies the stub queue


  56 //
  57 //                ________
  58 // stub       -->|        | <--+
  59 //               |  data  |    |
  60 //               |________|    |
  61 // code_begin -->|        |    |
  62 //               |        |    |
  63 //               |  code  |    | size
  64 //               |        |    |
  65 //               |________|    |
  66 // code_end   -->|        |    |
  67 //               |  data  |    |
  68 //               |________|    |
  69 //                          <--+
  70 
  71 
  72 class Stub VALUE_OBJ_CLASS_SPEC {
  73  public:
  74   // Initialization/finalization
  75   void    initialize(int size,
  76                      CodeStrings& strings)       { ShouldNotCallThis(); }                // called to initialize/specify the stub's size
  77   void    finalize()                             { ShouldNotCallThis(); }                // called before the stub is deallocated
  78 
  79   // General info/converters
  80   int     size() const                           { ShouldNotCallThis(); return 0; }      // must return the size provided by initialize
  81   static  int code_size_to_size(int code_size)   { ShouldNotCallThis(); return 0; }      // computes the size given the code size
  82 
  83   // Code info
  84   address code_begin() const                     { ShouldNotCallThis(); return NULL; }   // points to the first byte of    the code
  85   address code_end() const                       { ShouldNotCallThis(); return NULL; }   // points to the first byte after the code
  86 
  87   // Debugging
  88   void    verify()                               { ShouldNotCallThis(); }                // verifies the Stub
  89   void    print()                                { ShouldNotCallThis(); }                // prints some information about the stub
  90 };
  91 
  92 
  93 // A stub interface defines the interface between a stub queue
  94 // and the stubs it queues. In order to avoid a vtable and
  95 // (and thus the extra word) in each stub, a concrete stub
  96 // interface object is created and associated with a stub
  97 // buffer which in turn uses the stub interface to interact
  98 // with its stubs.
  99 //
 100 // StubInterface serves as an abstract base class. A concrete
 101 // stub interface implementation is a subclass of StubInterface,
 102 // forwarding its virtual function calls to non-virtual calls
 103 // of the concrete stub (see also macro below). There's exactly
 104 // one stub interface instance required per stub queue.
 105 
 106 class StubInterface: public CHeapObj<mtCode> {
 107  public:
 108   // Initialization/finalization
 109   virtual void    initialize(Stub* self, int size,
 110                              CodeStrings& strings)         = 0; // called after creation (called twice if allocated via (request, commit))
 111   virtual void    finalize(Stub* self)                     = 0; // called before deallocation
 112 
 113   // General info/converters
 114   virtual int     size(Stub* self) const                   = 0; // the total size of the stub in bytes (must be a multiple of CodeEntryAlignment)
 115   virtual int     code_size_to_size(int code_size) const   = 0; // computes the total stub size in bytes given the code size in bytes
 116 
 117   // Code info
 118   virtual address code_begin(Stub* self) const             = 0; // points to the first code byte
 119   virtual address code_end(Stub* self) const               = 0; // points to the first byte after the code
 120 
 121   // Debugging
 122   virtual void    verify(Stub* self)                       = 0; // verifies the stub
 123   virtual void    print(Stub* self)                        = 0; // prints information about the stub
 124 };
 125 
 126 
 127 // DEF_STUB_INTERFACE is used to create a concrete stub interface
 128 // class, forwarding stub interface calls to the corresponding
 129 // stub calls.
 130 
 131 #define DEF_STUB_INTERFACE(stub)                           \
 132   class stub##Interface: public StubInterface {            \
 133    private:                                                \
 134     static stub*    cast(Stub* self)                       { return (stub*)self; }                 \
 135                                                            \
 136    public:                                                 \
 137     /* Initialization/finalization */                      \
 138     virtual void    initialize(Stub* self, int size,       \
 139                                CodeStrings& strings)       { cast(self)->initialize(size, strings); } \
 140     virtual void    finalize(Stub* self)                   { cast(self)->finalize(); }             \
 141                                                            \
 142     /* General info */                                     \
 143     virtual int     size(Stub* self) const                 { return cast(self)->size(); }          \
 144     virtual int     code_size_to_size(int code_size) const { return stub::code_size_to_size(code_size); } \
 145                                                            \
 146     /* Code info */                                        \
 147     virtual address code_begin(Stub* self) const           { return cast(self)->code_begin(); }    \
 148     virtual address code_end(Stub* self) const             { return cast(self)->code_end(); }      \
 149                                                            \
 150     /* Debugging */                                        \
 151     virtual void    verify(Stub* self)                     { cast(self)->verify(); }               \
 152     virtual void    print(Stub* self)                      { cast(self)->print(); }                \
 153   };
 154 
 155 
 156 // A StubQueue maintains a queue of stubs.
 157 // Note: All sizes (spaces) are given in bytes.
 158 
 159 class StubQueue: public CHeapObj<mtCode> {
 160   friend class VMStructs;
 161  private:
 162   StubInterface* _stub_interface;                // the interface prototype
 163   address        _stub_buffer;                   // where all stubs are stored
 164   int            _buffer_size;                   // the buffer size in bytes
 165   int            _buffer_limit;                  // the (byte) index of the actual buffer limit (_buffer_limit <= _buffer_size)
 166   int            _queue_begin;                   // the (byte) index of the first queue entry (word-aligned)
 167   int            _queue_end;                     // the (byte) index of the first entry after the queue (word-aligned)
 168   int            _number_of_stubs;               // the number of buffered stubs
 169   Mutex* const   _mutex;                         // the lock used for a (request, commit) transaction
 170 
 171   void  check_index(int i) const                 { assert(0 <= i && i < _buffer_limit && i % CodeEntryAlignment == 0, "illegal index"); }
 172   bool  is_contiguous() const                    { return _queue_begin <= _queue_end; }
 173   int   index_of(Stub* s) const                  { int i = (address)s - _stub_buffer; check_index(i); return i; }
 174   Stub* stub_at(int i) const                     { check_index(i); return (Stub*)(_stub_buffer + i); }
 175   Stub* current_stub() const                     { return stub_at(_queue_end); }
 176 
 177   // Stub functionality accessed via interface
 178   void  stub_initialize(Stub* s, int size,
 179                         CodeStrings& strings)    { assert(size % CodeEntryAlignment == 0, "size not aligned"); _stub_interface->initialize(s, size, strings); }
 180   void  stub_finalize(Stub* s)                   { _stub_interface->finalize(s); }
 181   int   stub_size(Stub* s) const                 { return _stub_interface->size(s); }
 182   bool  stub_contains(Stub* s, address pc) const { return _stub_interface->code_begin(s) <= pc && pc < _stub_interface->code_end(s); }
 183   int   stub_code_size_to_size(int code_size) const { return _stub_interface->code_size_to_size(code_size); }
 184   void  stub_verify(Stub* s)                     { _stub_interface->verify(s); }
 185   void  stub_print(Stub* s)                      { _stub_interface->print(s); }
 186 
 187   static void register_queue(StubQueue*);
 188 
 189  public:
 190   StubQueue(StubInterface* stub_interface, int buffer_size, Mutex* lock,
 191             const char* name);
 192   ~StubQueue();
 193 
 194   // General queue info
 195   bool  is_empty() const                         { return _queue_begin == _queue_end; }
 196   int   total_space() const                      { return _buffer_size - 1; }
 197   int   available_space() const                  { int d = _queue_begin - _queue_end - 1; return d < 0 ? d + _buffer_size : d; }
 198   int   used_space() const                       { return total_space() - available_space(); }
 199   int   number_of_stubs() const                  { return _number_of_stubs; }
 200   bool  contains(address pc) const               { return _stub_buffer <= pc && pc < _stub_buffer + _buffer_limit; }
 201   Stub* stub_containing(address pc) const;
 202   address code_start() const                     { return _stub_buffer; }
 203   address code_end() const                       { return _stub_buffer + _buffer_limit; }
 204 
 205   // Stub allocation (atomic transactions)
 206   Stub* request_committed(int code_size);        // request a stub that provides exactly code_size space for code
 207   Stub* request(int requested_code_size);        // request a stub with a (maximum) code space - locks the queue
 208   void  commit (int committed_code_size,
 209                 CodeStrings& strings);           // commit the previously requested stub - unlocks the queue
 210 
 211   // Stub deallocation
 212   void  remove_first();                          // remove the first stub in the queue
 213   void  remove_first(int n);                     // remove the first n stubs in the queue
 214   void  remove_all();                            // remove all stubs in the queue
 215 
 216   // Iteration
 217   static void queues_do(void f(StubQueue* s));   // call f with each StubQueue
 218   void  stubs_do(void f(Stub* s));               // call f with all stubs
 219   Stub* first() const                            { return number_of_stubs() > 0 ? stub_at(_queue_begin) : NULL; }
 220   Stub* next(Stub* s) const                      { int i = index_of(s) + stub_size(s);
 221                                                    if (i == _buffer_limit) i = 0;
 222                                                    return (i == _queue_end) ? NULL : stub_at(i);
 223                                                  }
 224 
 225   address stub_code_begin(Stub* s) const         { return _stub_interface->code_begin(s); }
 226   address stub_code_end(Stub* s) const           { return _stub_interface->code_end(s);   }
 227 
 228   // Debugging/printing
 229   void  verify();                                // verifies the stub queue