69 70 // VtableStubs creates the code stubs for compiled calls through vtables. 71 // There is one stub per (vtable index, args_size) pair, and the stubs are 72 // never deallocated. They don't need to be GCed because they contain no oops. 73 class VtableStub; 74 75 class VtableStubs : AllStatic { 76 public: // N must be public (some compilers need this for _table) 77 enum { 78 N = 256, // size of stub table; must be power of two 79 mask = N - 1 80 }; 81 82 private: 83 friend class VtableStub; 84 static VtableStub* _table[N]; // table of existing stubs 85 static int _number_of_vtable_stubs; // number of stubs created so far (for statistics) 86 static int _vtab_stub_size; // current size estimate for vtable stub (quasi-constant) 87 static int _itab_stub_size; // current size estimate for itable stub (quasi-constant) 88 89 static VtableStub* create_vtable_stub(int vtable_index); 90 static VtableStub* create_itable_stub(int vtable_index); 91 static VtableStub* lookup (bool is_vtable_stub, int vtable_index); 92 static void enter (bool is_vtable_stub, int vtable_index, VtableStub* s); 93 static inline uint hash (bool is_vtable_stub, int vtable_index); 94 static address find_stub (bool is_vtable_stub, int vtable_index); 95 static void bookkeeping(MacroAssembler* masm, outputStream* out, VtableStub* s, 96 address npe_addr, address ame_addr, bool is_vtable_stub, 97 int index, int slop_bytes, int index_dependent_slop); 98 static int code_size_limit(bool is_vtable_stub); 99 static void check_and_set_size_limit(bool is_vtable_stub, 100 int code_size, 101 int padding); 102 103 public: 104 static address find_vtable_stub(int vtable_index) { return find_stub(true, vtable_index); } 105 static address find_itable_stub(int itable_index) { return find_stub(false, itable_index); } 106 107 static VtableStub* entry_point(address pc); // vtable stub entry point for a pc 108 static bool contains(address pc); // is pc within any stub? 109 static VtableStub* stub_containing(address pc); // stub containing pc or NULL 110 static int number_of_vtable_stubs() { return _number_of_vtable_stubs; } 111 static void initialize(); 112 static void vtable_stub_do(void f(VtableStub*)); // iterates over all vtable stubs 113 }; 114 115 116 class VtableStub { 117 private: 118 friend class VtableStubs; 119 120 static address _chunk; // For allocation 121 static address _chunk_end; // For allocation 122 static VMReg _receiver_location; // Where to find receiver 123 124 VtableStub* _next; // Pointer to next entry in hash table 125 const short _index; // vtable index 126 short _ame_offset; // Where an AbstractMethodError might occur 127 short _npe_offset; // Where a NullPointerException might occur 128 bool _is_vtable_stub; // True if vtable stub, false, is itable stub 129 /* code follows here */ // The vtableStub code 130 131 void* operator new(size_t size, int code_size) throw(); 132 133 VtableStub(bool is_vtable_stub, int index) 134 : _next(NULL), _index(index), _ame_offset(-1), _npe_offset(-1), 135 _is_vtable_stub(is_vtable_stub) {} 136 VtableStub* next() const { return _next; } 137 int index() const { return _index; } 138 static VMReg receiver_location() { return _receiver_location; } 139 void set_next(VtableStub* n) { _next = n; } 140 141 public: 142 address code_begin() const { return (address)(this + 1); } 143 address code_end() const { return code_begin() + VtableStubs::code_size_limit(_is_vtable_stub); } 144 address entry_point() const { return code_begin(); } 145 static int entry_offset() { return sizeof(class VtableStub); } 146 147 bool matches(bool is_vtable_stub, int index) const { 148 return _index == index && _is_vtable_stub == is_vtable_stub; 149 } 150 bool contains(address pc) const { return code_begin() <= pc && pc < code_end(); } 151 152 private: 153 void set_exception_points(address npe_addr, address ame_addr) { 154 _npe_offset = npe_addr - code_begin(); 155 _ame_offset = ame_addr - code_begin(); 156 assert(is_abstract_method_error(ame_addr), "offset must be correct"); 157 assert(is_null_pointer_exception(npe_addr), "offset must be correct"); 158 assert(!is_abstract_method_error(npe_addr), "offset must be correct"); 159 assert(!is_null_pointer_exception(ame_addr), "offset must be correct"); 160 } 161 162 // platform-dependent routines 163 static int pd_code_alignment(); 164 // CNC: Removed because vtable stubs are now made with an ideal graph 165 // static bool pd_disregard_arg_size(); 166 167 static void align_chunk() { 168 uintptr_t off = (uintptr_t)( _chunk + sizeof(VtableStub) ) % pd_code_alignment(); 169 if (off != 0) _chunk += pd_code_alignment() - off; 170 } 171 172 public: 173 // Query 174 bool is_itable_stub() { return !_is_vtable_stub; } 175 bool is_vtable_stub() { return _is_vtable_stub; } 176 bool is_abstract_method_error(address epc) { return epc == code_begin()+_ame_offset; } 177 bool is_null_pointer_exception(address epc) { return epc == code_begin()+_npe_offset; } 178 179 void print_on(outputStream* st) const; 180 void print() const { print_on(tty); } 181 182 }; 183 184 #endif // SHARE_CODE_VTABLESTUBS_HPP | 69 70 // VtableStubs creates the code stubs for compiled calls through vtables. 71 // There is one stub per (vtable index, args_size) pair, and the stubs are 72 // never deallocated. They don't need to be GCed because they contain no oops. 73 class VtableStub; 74 75 class VtableStubs : AllStatic { 76 public: // N must be public (some compilers need this for _table) 77 enum { 78 N = 256, // size of stub table; must be power of two 79 mask = N - 1 80 }; 81 82 private: 83 friend class VtableStub; 84 static VtableStub* _table[N]; // table of existing stubs 85 static int _number_of_vtable_stubs; // number of stubs created so far (for statistics) 86 static int _vtab_stub_size; // current size estimate for vtable stub (quasi-constant) 87 static int _itab_stub_size; // current size estimate for itable stub (quasi-constant) 88 89 static VtableStub* create_vtable_stub(int vtable_index, bool caller_is_c1); 90 static VtableStub* create_itable_stub(int vtable_index, bool caller_is_c1); 91 static VtableStub* lookup (bool is_vtable_stub, int vtable_index, bool caller_is_c1); 92 static void enter (bool is_vtable_stub, int vtable_index, bool caller_is_c1, VtableStub* s); 93 static inline uint hash (bool is_vtable_stub, int vtable_index, bool caller_is_c1); 94 static address find_stub (bool is_vtable_stub, int vtable_index, bool caller_is_c1); 95 static void bookkeeping(MacroAssembler* masm, outputStream* out, VtableStub* s, 96 address npe_addr, address ame_addr, bool is_vtable_stub, 97 int index, int slop_bytes, int index_dependent_slop); 98 static int code_size_limit(bool is_vtable_stub); 99 static void check_and_set_size_limit(bool is_vtable_stub, 100 int code_size, 101 int padding); 102 103 public: 104 static address find_vtable_stub(int vtable_index, bool caller_is_c1) { return find_stub(true, vtable_index, caller_is_c1); } 105 static address find_itable_stub(int itable_index, bool caller_is_c1) { return find_stub(false, itable_index, caller_is_c1); } 106 107 static VtableStub* entry_point(address pc); // vtable stub entry point for a pc 108 static bool contains(address pc); // is pc within any stub? 109 static VtableStub* stub_containing(address pc); // stub containing pc or NULL 110 static int number_of_vtable_stubs() { return _number_of_vtable_stubs; } 111 static void initialize(); 112 static void vtable_stub_do(void f(VtableStub*)); // iterates over all vtable stubs 113 }; 114 115 116 class VtableStub { 117 private: 118 friend class VtableStubs; 119 120 static address _chunk; // For allocation 121 static address _chunk_end; // For allocation 122 static VMReg _receiver_location; // Where to find receiver 123 124 VtableStub* _next; // Pointer to next entry in hash table 125 const short _index; // vtable index 126 short _ame_offset; // Where an AbstractMethodError might occur 127 short _npe_offset; // Where a NullPointerException might occur 128 bool _is_vtable_stub; // True if vtable stub, false, is itable stub 129 bool _caller_is_c1; // True if this is for a caller compiled by C1, 130 // which doesn't scalarize parameters. 131 /* code follows here */ // The vtableStub code 132 133 void* operator new(size_t size, int code_size) throw(); 134 135 VtableStub(bool is_vtable_stub, int index, bool caller_is_c1) 136 : _next(NULL), _index(index), _ame_offset(-1), _npe_offset(-1), 137 _is_vtable_stub(is_vtable_stub), _caller_is_c1(caller_is_c1) {} 138 VtableStub* next() const { return _next; } 139 int index() const { return _index; } 140 static VMReg receiver_location() { return _receiver_location; } 141 void set_next(VtableStub* n) { _next = n; } 142 143 public: 144 address code_begin() const { return (address)(this + 1); } 145 address code_end() const { return code_begin() + VtableStubs::code_size_limit(_is_vtable_stub); } 146 address entry_point() const { return code_begin(); } 147 static int entry_offset() { return sizeof(class VtableStub); } 148 149 bool matches(bool is_vtable_stub, int index, bool caller_is_c1) const { 150 return _index == index && _is_vtable_stub == is_vtable_stub && _caller_is_c1 == caller_is_c1; 151 } 152 bool contains(address pc) const { return code_begin() <= pc && pc < code_end(); } 153 154 private: 155 void set_exception_points(address npe_addr, address ame_addr) { 156 _npe_offset = npe_addr - code_begin(); 157 _ame_offset = ame_addr - code_begin(); 158 assert(is_abstract_method_error(ame_addr), "offset must be correct"); 159 assert(is_null_pointer_exception(npe_addr), "offset must be correct"); 160 assert(!is_abstract_method_error(npe_addr), "offset must be correct"); 161 assert(!is_null_pointer_exception(ame_addr), "offset must be correct"); 162 } 163 164 // platform-dependent routines 165 static int pd_code_alignment(); 166 // CNC: Removed because vtable stubs are now made with an ideal graph 167 // static bool pd_disregard_arg_size(); 168 169 static void align_chunk() { 170 uintptr_t off = (uintptr_t)( _chunk + sizeof(VtableStub) ) % pd_code_alignment(); 171 if (off != 0) _chunk += pd_code_alignment() - off; 172 } 173 174 public: 175 // Query 176 bool is_itable_stub() { return !_is_vtable_stub; } 177 bool is_vtable_stub() { return _is_vtable_stub; } 178 bool caller_is_c1() { return _caller_is_c1; } 179 bool is_abstract_method_error(address epc) { return epc == code_begin()+_ame_offset; } 180 bool is_null_pointer_exception(address epc) { return epc == code_begin()+_npe_offset; } 181 182 void print_on(outputStream* st) const; 183 void print() const { print_on(tty); } 184 185 }; 186 187 #endif // SHARE_CODE_VTABLESTUBS_HPP |