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src/hotspot/share/oops/cpCache.hpp

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 32 #include "runtime/handles.hpp"
 33 #include "utilities/align.hpp"
 34 #include "utilities/constantTag.hpp"
 35 #include "utilities/growableArray.hpp"
 36 
 37 // The ConstantPoolCache is not a cache! It is the resolution table that the
 38 // interpreter uses to avoid going into the runtime and a way to access resolved
 39 // values.
 40 
 41 // A ConstantPoolCacheEntry describes an individual entry of the constant
 42 // pool cache. There's 2 principal kinds of entries: field entries for in-
 43 // stance & static field access, and method entries for invokes. Some of
 44 // the entry layout is shared and looks as follows:
 45 //
 46 // bit number |31                0|
 47 // bit length |-8--|-8--|---16----|
 48 // --------------------------------
 49 // _indices   [ b2 | b1 |  index  ]  index = constant_pool_index
 50 // _f1        [  entry specific   ]  metadata ptr (method or klass)
 51 // _f2        [  entry specific   ]  vtable or res_ref index, or vfinal method ptr
 52 // _flags     [tos|0|F=1|0|0|0|f|v|0 |0000|field_index] (for field entries)
 53 // bit length [ 4 |1| 1 |1|1|1|1|1|1 |1     |-3-|----16-----]
 54 // _flags     [tos|0|F=0|S|A|I|f|0|vf|indy_rf|000|00000|psize] (for method entries)
 55 // bit length [ 4 |1| 1 |1|1|1|1|1|1 |-4--|--8--|--8--]
 56 
 57 // --------------------------------
 58 //
 59 // with:
 60 // index  = original constant pool index
 61 // b1     = bytecode 1
 62 // b2     = bytecode 2
 63 // psize  = parameters size (method entries only)
 64 // field_index = index into field information in holder InstanceKlass
 65 //          The index max is 0xffff (max number of fields in constant pool)
 66 //          and is multiplied by (InstanceKlass::next_offset) when accessing.
 67 // tos    = TosState
 68 // F      = the entry is for a field (or F=0 for a method)
 69 // A      = call site has an appendix argument (loaded from resolved references)
 70 // I      = interface call is forced virtual (must use a vtable index or vfinal)
 71 // f      = field or method is final
 72 // v      = field is volatile
 73 // vf     = virtual but final (method entries only: is_vfinal())
 74 // indy_rf = call site specifier method resolution failed
 75 //
 76 // The flags after TosState have the following interpretation:
 77 // bit 27: 0 for fields, 1 for methods


 78 // f  flag true if field is marked final
 79 // v  flag true if field is volatile (only for fields)
 80 // f2 flag true if f2 contains an oop (e.g., virtual final method)
 81 // fv flag true if invokeinterface used for method in class Object
 82 //
 83 // The flags 31, 30, 29, 28 together build a 4 bit number 0 to 16 with the
 84 // following mapping to the TosState states:
 85 //
 86 // btos: 0
 87 // ztos: 1
 88 // ctos: 2
 89 // stos: 3
 90 // itos: 4
 91 // ltos: 5
 92 // ftos: 6
 93 // dtos: 7
 94 // atos: 8
 95 // vtos: 9
 96 //
 97 // Entry specific: field entries:

165     assert((field_index & field_index_mask) == field_index, "field_index in range");
166     set_flags(make_flags(field_type, option_bits | (1 << is_field_entry_shift), field_index));
167   }
168   void set_method_flags(TosState return_type, int option_bits, int method_params) {
169     assert((method_params & parameter_size_mask) == method_params, "method_params in range");
170     set_flags(make_flags(return_type, option_bits, method_params));
171   }
172 
173  public:
174   // specific bit definitions for the flags field:
175   // (Note: the interpreter must use these definitions to access the CP cache.)
176   enum {
177     // high order bits are the TosState corresponding to field type or method return type
178     tos_state_bits             = 4,
179     tos_state_mask             = right_n_bits(tos_state_bits),
180     tos_state_shift            = BitsPerInt - tos_state_bits,  // see verify_tos_state_shift below
181     // misc. option bits; can be any bit position in [16..27]
182     is_field_entry_shift       = 26,  // (F) is it a field or a method?
183     has_local_signature_shift  = 25,  // (S) does the call site have a per-site signature (sig-poly methods)?
184     has_appendix_shift         = 24,  // (A) does the call site have an appendix argument?

185     is_forced_virtual_shift    = 23,  // (I) is the interface reference forced to virtual mode?

186     is_final_shift             = 22,  // (f) is the field or method final?
187     is_volatile_shift          = 21,  // (v) is the field volatile?
188     is_vfinal_shift            = 20,  // (vf) did the call resolve to a final method?
189     indy_resolution_failed_shift= 19, // (indy_rf) did call site specifier resolution fail ?
190     // low order bits give field index (for FieldInfo) or method parameter size:
191     field_index_bits           = 16,
192     field_index_mask           = right_n_bits(field_index_bits),
193     parameter_size_bits        = 8,  // subset of field_index_mask, range is 0..255
194     parameter_size_mask        = right_n_bits(parameter_size_bits),
195     option_bits_mask           = ~(((~0u) << tos_state_shift) | (field_index_mask | parameter_size_mask))
196   };
197 
198   // specific bit definitions for the indices field:
199   enum {
200     cp_index_bits              = 2*BitsPerByte,
201     cp_index_mask              = right_n_bits(cp_index_bits),
202     bytecode_1_shift           = cp_index_bits,
203     bytecode_1_mask            = right_n_bits(BitsPerByte), // == (u1)0xFF
204     bytecode_2_shift           = cp_index_bits + BitsPerByte,
205     bytecode_2_mask            = right_n_bits(BitsPerByte)  // == (u1)0xFF
206   };
207 
208 
209   // Initialization
210   void initialize_entry(int original_index);     // initialize primary entry
211   void initialize_resolved_reference_index(int ref_index) {
212     assert(_f2 == 0, "set once");  // note: ref_index might be zero also
213     _f2 = ref_index;
214   }
215 
216   void set_field(                                // sets entry to resolved field state
217     Bytecodes::Code get_code,                    // the bytecode used for reading the field
218     Bytecodes::Code put_code,                    // the bytecode used for writing the field
219     Klass*          field_holder,                // the object/klass holding the field
220     int             orig_field_index,            // the original field index in the field holder
221     int             field_offset,                // the field offset in words in the field holder
222     TosState        field_type,                  // the (machine) field type
223     bool            is_final,                    // the field is final
224     bool            is_volatile                  // the field is volatile


225   );
226 
227  private:
228   void set_direct_or_vtable_call(
229     Bytecodes::Code invoke_code,                 // the bytecode used for invoking the method
230     const methodHandle& method,                  // the method/prototype if any (NULL, otherwise)
231     int             vtable_index,                // the vtable index if any, else negative
232     bool            sender_is_interface
233   );
234 
235  public:
236   void set_direct_call(                          // sets entry to exact concrete method entry
237     Bytecodes::Code invoke_code,                 // the bytecode used for invoking the method
238     const methodHandle& method,                  // the method to call
239     bool            sender_is_interface
240   );
241 
242   void set_vtable_call(                          // sets entry to vtable index
243     Bytecodes::Code invoke_code,                 // the bytecode used for invoking the method
244     const methodHandle& method,                  // resolved method which declares the vtable index

293   // invokedynamic and invokehandle call sites have an "appendix" item in the
294   // resolved references array.
295   Method*      method_if_resolved(const constantPoolHandle& cpool);
296   oop        appendix_if_resolved(const constantPoolHandle& cpool);
297 
298   void set_parameter_size(int value);
299 
300   // Which bytecode number (1 or 2) in the index field is valid for this bytecode?
301   // Returns -1 if neither is valid.
302   static int bytecode_number(Bytecodes::Code code) {
303     switch (code) {
304       case Bytecodes::_getstatic       :    // fall through
305       case Bytecodes::_getfield        :    // fall through
306       case Bytecodes::_invokespecial   :    // fall through
307       case Bytecodes::_invokestatic    :    // fall through
308       case Bytecodes::_invokehandle    :    // fall through
309       case Bytecodes::_invokedynamic   :    // fall through
310       case Bytecodes::_invokeinterface : return 1;
311       case Bytecodes::_putstatic       :    // fall through
312       case Bytecodes::_putfield        :    // fall through

313       case Bytecodes::_invokevirtual   : return 2;
314       default                          : break;
315     }
316     return -1;
317   }
318 
319   // Has this bytecode been resolved? Only valid for invokes and get/put field/static.
320   bool is_resolved(Bytecodes::Code code) const;
321 
322   // Accessors
323   int indices() const                            { return _indices; }
324   int indices_ord() const;
325   int constant_pool_index() const                { return (indices() & cp_index_mask); }
326   Bytecodes::Code bytecode_1() const;
327   Bytecodes::Code bytecode_2() const;
328   Metadata* f1_ord() const;
329   Method*   f1_as_method() const;
330   Klass*    f1_as_klass() const;
331   // Use the accessor f1() to acquire _f1's value. This is needed for
332   // example in BytecodeInterpreter::run(), where is_f1_null() is
333   // called to check if an invokedynamic call is resolved. This load
334   // of _f1 must be ordered with the loads performed by
335   // cache->main_entry_index().
336   bool      is_f1_null() const;  // classifies a CPC entry as unbound
337   int       f2_as_index() const                  { assert(!is_vfinal(), ""); return (int) _f2; }
338   Method*   f2_as_vfinal_method() const          { assert(is_vfinal(), ""); return (Method*)_f2; }
339   Method*   f2_as_interface_method() const;

340   intx flags_ord() const;
341   int  field_index() const                       { assert(is_field_entry(),  ""); return (_flags & field_index_mask); }
342   int  parameter_size() const                    { assert(is_method_entry(), ""); return (_flags & parameter_size_mask); }
343   bool is_volatile() const                       { return (_flags & (1 << is_volatile_shift))       != 0; }
344   bool is_final() const                          { return (_flags & (1 << is_final_shift))          != 0; }

345   bool is_forced_virtual() const                 { return (_flags & (1 << is_forced_virtual_shift)) != 0; }
346   bool is_vfinal() const                         { return (_flags & (1 << is_vfinal_shift))         != 0; }
347   bool indy_resolution_failed() const;
348   bool has_appendix() const;
349   bool has_local_signature() const;
350   bool is_method_entry() const                   { return (_flags & (1 << is_field_entry_shift))    == 0; }
351   bool is_field_entry() const                    { return (_flags & (1 << is_field_entry_shift))    != 0; }
352   bool is_long() const                           { return flag_state() == ltos; }
353   bool is_double() const                         { return flag_state() == dtos; }

354   TosState flag_state() const                    { assert((uint)number_of_states <= (uint)tos_state_mask+1, "");
355                                                    return (TosState)((_flags >> tos_state_shift) & tos_state_mask); }
356   void set_indy_resolution_failed();
357 
358   // Code generation support
359   static WordSize size()                         {
360     return in_WordSize(align_up((int)sizeof(ConstantPoolCacheEntry), wordSize) / wordSize);
361   }
362   static ByteSize size_in_bytes()                { return in_ByteSize(sizeof(ConstantPoolCacheEntry)); }
363   static ByteSize indices_offset()               { return byte_offset_of(ConstantPoolCacheEntry, _indices); }
364   static ByteSize f1_offset()                    { return byte_offset_of(ConstantPoolCacheEntry, _f1); }
365   static ByteSize f2_offset()                    { return byte_offset_of(ConstantPoolCacheEntry, _f2); }
366   static ByteSize flags_offset()                 { return byte_offset_of(ConstantPoolCacheEntry, _flags); }
367 
368 #if INCLUDE_JVMTI
369   // RedefineClasses() API support:
370   // If this ConstantPoolCacheEntry refers to old_method then update it
371   // to refer to new_method.
372   // trace_name_printed is set to true if the current call has
373   // printed the klass name so that other routines in the adjust_*

 32 #include "runtime/handles.hpp"
 33 #include "utilities/align.hpp"
 34 #include "utilities/constantTag.hpp"
 35 #include "utilities/growableArray.hpp"
 36 
 37 // The ConstantPoolCache is not a cache! It is the resolution table that the
 38 // interpreter uses to avoid going into the runtime and a way to access resolved
 39 // values.
 40 
 41 // A ConstantPoolCacheEntry describes an individual entry of the constant
 42 // pool cache. There's 2 principal kinds of entries: field entries for in-
 43 // stance & static field access, and method entries for invokes. Some of
 44 // the entry layout is shared and looks as follows:
 45 //
 46 // bit number |31                0|
 47 // bit length |-8--|-8--|---16----|
 48 // --------------------------------
 49 // _indices   [ b2 | b1 |  index  ]  index = constant_pool_index
 50 // _f1        [  entry specific   ]  metadata ptr (method or klass)
 51 // _f2        [  entry specific   ]  vtable or res_ref index, or vfinal method ptr
 52 // _flags     [tos|0|F=1|0|I|i|f|v|0 |0000|field_index] (for field entries)
 53 // bit length [ 4 |1| 1 |1|1|1|1|1|1 |1     |-3-|----16-----]
 54 // _flags     [tos|0|F=0|S|A|I|f|0|vf|indy_rf|000|00000|psize] (for method entries)
 55 // bit length [ 4 |1| 1 |1|1|1|1|1|1 |-4--|--8--|--8--]
 56 
 57 // --------------------------------
 58 //
 59 // with:
 60 // index  = original constant pool index
 61 // b1     = bytecode 1
 62 // b2     = bytecode 2
 63 // psize  = parameters size (method entries only)
 64 // field_index = index into field information in holder InstanceKlass
 65 //          The index max is 0xffff (max number of fields in constant pool)
 66 //          and is multiplied by (InstanceKlass::next_offset) when accessing.
 67 // tos    = TosState
 68 // F      = the entry is for a field (or F=0 for a method)
 69 // A      = call site has an appendix argument (loaded from resolved references)
 70 // I      = interface call is forced virtual (must use a vtable index or vfinal)
 71 // f      = field or method is final
 72 // v      = field is volatile
 73 // vf     = virtual but final (method entries only: is_vfinal())
 74 // indy_rf = call site specifier method resolution failed
 75 //
 76 // The flags after TosState have the following interpretation:
 77 // bit 27: 0 for fields, 1 for methods
 78 // I  flag true if field is a null free inline type (must never be null)
 79 // i  flag true if field is inlined
 80 // f  flag true if field is marked final
 81 // v  flag true if field is volatile (only for fields)
 82 // f2 flag true if f2 contains an oop (e.g., virtual final method)
 83 // fv flag true if invokeinterface used for method in class Object
 84 //
 85 // The flags 31, 30, 29, 28 together build a 4 bit number 0 to 16 with the
 86 // following mapping to the TosState states:
 87 //
 88 // btos: 0
 89 // ztos: 1
 90 // ctos: 2
 91 // stos: 3
 92 // itos: 4
 93 // ltos: 5
 94 // ftos: 6
 95 // dtos: 7
 96 // atos: 8
 97 // vtos: 9
 98 //
 99 // Entry specific: field entries:

167     assert((field_index & field_index_mask) == field_index, "field_index in range");
168     set_flags(make_flags(field_type, option_bits | (1 << is_field_entry_shift), field_index));
169   }
170   void set_method_flags(TosState return_type, int option_bits, int method_params) {
171     assert((method_params & parameter_size_mask) == method_params, "method_params in range");
172     set_flags(make_flags(return_type, option_bits, method_params));
173   }
174 
175  public:
176   // specific bit definitions for the flags field:
177   // (Note: the interpreter must use these definitions to access the CP cache.)
178   enum {
179     // high order bits are the TosState corresponding to field type or method return type
180     tos_state_bits             = 4,
181     tos_state_mask             = right_n_bits(tos_state_bits),
182     tos_state_shift            = BitsPerInt - tos_state_bits,  // see verify_tos_state_shift below
183     // misc. option bits; can be any bit position in [16..27]
184     is_field_entry_shift       = 26,  // (F) is it a field or a method?
185     has_local_signature_shift  = 25,  // (S) does the call site have a per-site signature (sig-poly methods)?
186     has_appendix_shift         = 24,  // (A) does the call site have an appendix argument?
187     is_null_free_inline_type_shift = 24,  // (I) is the field a null free inline type (must never be null)
188     is_forced_virtual_shift    = 23,  // (I) is the interface reference forced to virtual mode?
189     is_inlined_shift           = 23,  // (i) is the field inlined?
190     is_final_shift             = 22,  // (f) is the field or method final?
191     is_volatile_shift          = 21,  // (v) is the field volatile?
192     is_vfinal_shift            = 20,  // (vf) did the call resolve to a final method?
193     indy_resolution_failed_shift= 19, // (indy_rf) did call site specifier resolution fail ?
194     // low order bits give field index (for FieldInfo) or method parameter size:
195     field_index_bits           = 16,
196     field_index_mask           = right_n_bits(field_index_bits),
197     parameter_size_bits        = 8,  // subset of field_index_mask, range is 0..255
198     parameter_size_mask        = right_n_bits(parameter_size_bits),
199     option_bits_mask           = ~(((~0u) << tos_state_shift) | (field_index_mask | parameter_size_mask))
200   };
201 
202   // specific bit definitions for the indices field:
203   enum {
204     cp_index_bits              = 2*BitsPerByte,
205     cp_index_mask              = right_n_bits(cp_index_bits),
206     bytecode_1_shift           = cp_index_bits,
207     bytecode_1_mask            = right_n_bits(BitsPerByte), // == (u1)0xFF
208     bytecode_2_shift           = cp_index_bits + BitsPerByte,
209     bytecode_2_mask            = right_n_bits(BitsPerByte)  // == (u1)0xFF
210   };
211 
212 
213   // Initialization
214   void initialize_entry(int original_index);     // initialize primary entry
215   void initialize_resolved_reference_index(int ref_index) {
216     assert(_f2 == 0, "set once");  // note: ref_index might be zero also
217     _f2 = ref_index;
218   }
219 
220   void set_field(                                // sets entry to resolved field state
221     Bytecodes::Code get_code,                    // the bytecode used for reading the field
222     Bytecodes::Code put_code,                    // the bytecode used for writing the field
223     Klass*          field_holder,                // the object/klass holding the field
224     int             orig_field_index,            // the original field index in the field holder
225     int             field_offset,                // the field offset in words in the field holder
226     TosState        field_type,                  // the (machine) field type
227     bool            is_final,                    // the field is final
228     bool            is_volatile,                 // the field is volatile
229     bool            is_inlined,                  // the field is inlined
230     bool            is_null_free_inline_type     // the field is an inline type (must never be null)
231   );
232 
233  private:
234   void set_direct_or_vtable_call(
235     Bytecodes::Code invoke_code,                 // the bytecode used for invoking the method
236     const methodHandle& method,                  // the method/prototype if any (NULL, otherwise)
237     int             vtable_index,                // the vtable index if any, else negative
238     bool            sender_is_interface
239   );
240 
241  public:
242   void set_direct_call(                          // sets entry to exact concrete method entry
243     Bytecodes::Code invoke_code,                 // the bytecode used for invoking the method
244     const methodHandle& method,                  // the method to call
245     bool            sender_is_interface
246   );
247 
248   void set_vtable_call(                          // sets entry to vtable index
249     Bytecodes::Code invoke_code,                 // the bytecode used for invoking the method
250     const methodHandle& method,                  // resolved method which declares the vtable index

299   // invokedynamic and invokehandle call sites have an "appendix" item in the
300   // resolved references array.
301   Method*      method_if_resolved(const constantPoolHandle& cpool);
302   oop        appendix_if_resolved(const constantPoolHandle& cpool);
303 
304   void set_parameter_size(int value);
305 
306   // Which bytecode number (1 or 2) in the index field is valid for this bytecode?
307   // Returns -1 if neither is valid.
308   static int bytecode_number(Bytecodes::Code code) {
309     switch (code) {
310       case Bytecodes::_getstatic       :    // fall through
311       case Bytecodes::_getfield        :    // fall through
312       case Bytecodes::_invokespecial   :    // fall through
313       case Bytecodes::_invokestatic    :    // fall through
314       case Bytecodes::_invokehandle    :    // fall through
315       case Bytecodes::_invokedynamic   :    // fall through
316       case Bytecodes::_invokeinterface : return 1;
317       case Bytecodes::_putstatic       :    // fall through
318       case Bytecodes::_putfield        :    // fall through
319       case Bytecodes::_withfield       :    // fall through
320       case Bytecodes::_invokevirtual   : return 2;
321       default                          : break;
322     }
323     return -1;
324   }
325 
326   // Has this bytecode been resolved? Only valid for invokes and get/put field/static.
327   bool is_resolved(Bytecodes::Code code) const;
328 
329   // Accessors
330   int indices() const                            { return _indices; }
331   int indices_ord() const;
332   int constant_pool_index() const                { return (indices() & cp_index_mask); }
333   Bytecodes::Code bytecode_1() const;
334   Bytecodes::Code bytecode_2() const;
335   Metadata* f1_ord() const;
336   Method*   f1_as_method() const;
337   Klass*    f1_as_klass() const;
338   // Use the accessor f1() to acquire _f1's value. This is needed for
339   // example in BytecodeInterpreter::run(), where is_f1_null() is
340   // called to check if an invokedynamic call is resolved. This load
341   // of _f1 must be ordered with the loads performed by
342   // cache->main_entry_index().
343   bool      is_f1_null() const;  // classifies a CPC entry as unbound
344   int       f2_as_index() const                  { assert(!is_vfinal(), ""); return (int) _f2; }
345   Method*   f2_as_vfinal_method() const          { assert(is_vfinal(), ""); return (Method*)_f2; }
346   Method*   f2_as_interface_method() const;
347   int       f2_as_offset() const                 { assert(is_field_entry(),  ""); return (int)_f2; }
348   intx flags_ord() const;
349   int  field_index() const                       { assert(is_field_entry(),  ""); return (_flags & field_index_mask); }
350   int  parameter_size() const                    { assert(is_method_entry(), ""); return (_flags & parameter_size_mask); }
351   bool is_volatile() const                       { return (_flags & (1 << is_volatile_shift))       != 0; }
352   bool is_final() const                          { return (_flags & (1 << is_final_shift))          != 0; }
353   bool is_inlined() const                        { return  (_flags & (1 << is_inlined_shift))       != 0; }
354   bool is_forced_virtual() const                 { return (_flags & (1 << is_forced_virtual_shift)) != 0; }
355   bool is_vfinal() const                         { return (_flags & (1 << is_vfinal_shift))         != 0; }
356   bool indy_resolution_failed() const;
357   bool has_appendix() const;
358   bool has_local_signature() const;
359   bool is_method_entry() const                   { return (_flags & (1 << is_field_entry_shift))    == 0; }
360   bool is_field_entry() const                    { return (_flags & (1 << is_field_entry_shift))    != 0; }
361   bool is_long() const                           { return flag_state() == ltos; }
362   bool is_double() const                         { return flag_state() == dtos; }
363   bool is_null_free_inline_type() const          { return (_flags & (1 << is_null_free_inline_type_shift)) != 0; }
364   TosState flag_state() const                    { assert((uint)number_of_states <= (uint)tos_state_mask+1, "");
365                                                    return (TosState)((_flags >> tos_state_shift) & tos_state_mask); }
366   void set_indy_resolution_failed();
367 
368   // Code generation support
369   static WordSize size()                         {
370     return in_WordSize(align_up((int)sizeof(ConstantPoolCacheEntry), wordSize) / wordSize);
371   }
372   static ByteSize size_in_bytes()                { return in_ByteSize(sizeof(ConstantPoolCacheEntry)); }
373   static ByteSize indices_offset()               { return byte_offset_of(ConstantPoolCacheEntry, _indices); }
374   static ByteSize f1_offset()                    { return byte_offset_of(ConstantPoolCacheEntry, _f1); }
375   static ByteSize f2_offset()                    { return byte_offset_of(ConstantPoolCacheEntry, _f2); }
376   static ByteSize flags_offset()                 { return byte_offset_of(ConstantPoolCacheEntry, _flags); }
377 
378 #if INCLUDE_JVMTI
379   // RedefineClasses() API support:
380   // If this ConstantPoolCacheEntry refers to old_method then update it
381   // to refer to new_method.
382   // trace_name_printed is set to true if the current call has
383   // printed the klass name so that other routines in the adjust_*
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