cpCache.hpp revision 3602:da91efe96a93
1/* 2 * Copyright (c) 1998, 2012, Oracle and/or its affiliates. All rights reserved. 3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. 4 * 5 * This code is free software; you can redistribute it and/or modify it 6 * under the terms of the GNU General Public License version 2 only, as 7 * published by the Free Software Foundation. 8 * 9 * This code is distributed in the hope that it will be useful, but WITHOUT 10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 12 * version 2 for more details (a copy is included in the LICENSE file that 13 * accompanied this code). 14 * 15 * You should have received a copy of the GNU General Public License version 16 * 2 along with this work; if not, write to the Free Software Foundation, 17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 18 * 19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 20 * or visit www.oracle.com if you need additional information or have any 21 * questions. 22 * 23 */ 24 25#ifndef SHARE_VM_OOPS_CPCACHEOOP_HPP 26#define SHARE_VM_OOPS_CPCACHEOOP_HPP 27 28#include "interpreter/bytecodes.hpp" 29#include "memory/allocation.hpp" 30#include "utilities/array.hpp" 31 32class PSPromotionManager; 33 34// A ConstantPoolCacheEntry describes an individual entry of the constant 35// pool cache. There's 2 principal kinds of entries: field entries for in- 36// stance & static field access, and method entries for invokes. Some of 37// the entry layout is shared and looks as follows: 38// 39// bit number |31 0| 40// bit length |-8--|-8--|---16----| 41// -------------------------------- 42// _indices [ b2 | b1 | index ] index = constant_pool_index 43// _f1 [ entry specific ] metadata ptr (method or klass) 44// _f2 [ entry specific ] vtable or res_ref index, or vfinal method ptr 45// _flags [tos|0|F=1|0|0|f|v|0 |00000|field_index] (for field entries) 46// bit length [ 4 |1| 1 |1|1|1|1|1 |--5--|----16-----] 47// _flags [tos|0|F=0|A|I|f|0|vf|00000|00000|psize] (for method entries) 48// bit length [ 4 |1| 1 |1|1|1|1|1 |--5--|--8--|--8--] 49 50// -------------------------------- 51// 52// with: 53// index = original constant pool index 54// b1 = bytecode 1 55// b2 = bytecode 2 56// psize = parameters size (method entries only) 57// field_index = index into field information in holder InstanceKlass 58// The index max is 0xffff (max number of fields in constant pool) 59// and is multiplied by (InstanceKlass::next_offset) when accessing. 60// tos = TosState 61// F = the entry is for a field (or F=0 for a method) 62// A = call site has an appendix argument (loaded from resolved references) 63// I = interface call is forced virtual (must use a vtable index or vfinal) 64// f = field or method is final 65// v = field is volatile 66// vf = virtual but final (method entries only: is_vfinal()) 67// 68// The flags after TosState have the following interpretation: 69// bit 27: 0 for fields, 1 for methods 70// f flag true if field is marked final 71// v flag true if field is volatile (only for fields) 72// f2 flag true if f2 contains an oop (e.g., virtual final method) 73// fv flag true if invokeinterface used for method in class Object 74// 75// The flags 31, 30, 29, 28 together build a 4 bit number 0 to 8 with the 76// following mapping to the TosState states: 77// 78// btos: 0 79// ctos: 1 80// stos: 2 81// itos: 3 82// ltos: 4 83// ftos: 5 84// dtos: 6 85// atos: 7 86// vtos: 8 87// 88// Entry specific: field entries: 89// _indices = get (b1 section) and put (b2 section) bytecodes, original constant pool index 90// _f1 = field holder (as a java.lang.Class, not a Klass*) 91// _f2 = field offset in bytes 92// _flags = field type information, original FieldInfo index in field holder 93// (field_index section) 94// 95// Entry specific: method entries: 96// _indices = invoke code for f1 (b1 section), invoke code for f2 (b2 section), 97// original constant pool index 98// _f1 = Method* for non-virtual calls, unused by virtual calls. 99// for interface calls, which are essentially virtual but need a klass, 100// contains Klass* for the corresponding interface. 101// for invokedynamic, f1 contains a site-specific CallSite object (as an appendix) 102// for invokehandle, f1 contains a site-specific MethodType object (as an appendix) 103// (upcoming metadata changes will move the appendix to a separate array) 104// _f2 = vtable/itable index (or final Method*) for virtual calls only, 105// unused by non-virtual. The is_vfinal flag indicates this is a 106// method pointer for a final method, not an index. 107// _flags = method type info (t section), 108// virtual final bit (vfinal), 109// parameter size (psize section) 110// 111// Note: invokevirtual & invokespecial bytecodes can share the same constant 112// pool entry and thus the same constant pool cache entry. All invoke 113// bytecodes but invokevirtual use only _f1 and the corresponding b1 114// bytecode, while invokevirtual uses only _f2 and the corresponding 115// b2 bytecode. The value of _flags is shared for both types of entries. 116// 117// The fields are volatile so that they are stored in the order written in the 118// source code. The _indices field with the bytecode must be written last. 119 120class ConstantPoolCacheEntry VALUE_OBJ_CLASS_SPEC { 121 friend class VMStructs; 122 friend class constantPoolCacheKlass; 123 friend class ConstantPool; 124 friend class InterpreterRuntime; 125 126 private: 127 volatile intx _indices; // constant pool index & rewrite bytecodes 128 volatile Metadata* _f1; // entry specific metadata field 129 volatile intx _f2; // entry specific int/metadata field 130 volatile intx _flags; // flags 131 132 133 void set_bytecode_1(Bytecodes::Code code); 134 void set_bytecode_2(Bytecodes::Code code); 135 void set_f1(Metadata* f1) { 136 Metadata* existing_f1 = (Metadata*)_f1; // read once 137 assert(existing_f1 == NULL || existing_f1 == f1, "illegal field change"); 138 _f1 = f1; 139 } 140 void release_set_f1(Metadata* f1); 141 void set_f2(intx f2) { assert(_f2 == 0 || _f2 == f2, "illegal field change"); _f2 = f2; } 142 void set_f2_as_vfinal_method(Method* f2) { assert(_f2 == 0 || _f2 == (intptr_t) f2, "illegal field change"); assert(is_vfinal(), "flags must be set"); _f2 = (intptr_t) f2; } 143 int make_flags(TosState state, int option_bits, int field_index_or_method_params); 144 void set_flags(intx flags) { _flags = flags; } 145 bool init_flags_atomic(intx flags); 146 void set_field_flags(TosState field_type, int option_bits, int field_index) { 147 assert((field_index & field_index_mask) == field_index, "field_index in range"); 148 set_flags(make_flags(field_type, option_bits | (1 << is_field_entry_shift), field_index)); 149 } 150 void set_method_flags(TosState return_type, int option_bits, int method_params) { 151 assert((method_params & parameter_size_mask) == method_params, "method_params in range"); 152 set_flags(make_flags(return_type, option_bits, method_params)); 153 } 154 bool init_method_flags_atomic(TosState return_type, int option_bits, int method_params) { 155 assert((method_params & parameter_size_mask) == method_params, "method_params in range"); 156 return init_flags_atomic(make_flags(return_type, option_bits, method_params)); 157 } 158 159 public: 160 // specific bit definitions for the flags field: 161 // (Note: the interpreter must use these definitions to access the CP cache.) 162 enum { 163 // high order bits are the TosState corresponding to field type or method return type 164 tos_state_bits = 4, 165 tos_state_mask = right_n_bits(tos_state_bits), 166 tos_state_shift = BitsPerInt - tos_state_bits, // see verify_tos_state_shift below 167 // misc. option bits; can be any bit position in [16..27] 168 is_field_entry_shift = 26, // (F) is it a field or a method? 169 has_appendix_shift = 25, // (A) does the call site have an appendix argument? 170 is_forced_virtual_shift = 24, // (I) is the interface reference forced to virtual mode? 171 is_final_shift = 23, // (f) is the field or method final? 172 is_volatile_shift = 22, // (v) is the field volatile? 173 is_vfinal_shift = 21, // (vf) did the call resolve to a final method? 174 // low order bits give field index (for FieldInfo) or method parameter size: 175 field_index_bits = 16, 176 field_index_mask = right_n_bits(field_index_bits), 177 parameter_size_bits = 8, // subset of field_index_mask, range is 0..255 178 parameter_size_mask = right_n_bits(parameter_size_bits), 179 option_bits_mask = ~(((-1) << tos_state_shift) | (field_index_mask | parameter_size_mask)) 180 }; 181 182 // specific bit definitions for the indices field: 183 enum { 184 cp_index_bits = 2*BitsPerByte, 185 cp_index_mask = right_n_bits(cp_index_bits), 186 bytecode_1_shift = cp_index_bits, 187 bytecode_1_mask = right_n_bits(BitsPerByte), // == (u1)0xFF 188 bytecode_2_shift = cp_index_bits + BitsPerByte, 189 bytecode_2_mask = right_n_bits(BitsPerByte) // == (u1)0xFF 190 }; 191 192 193 // Initialization 194 void initialize_entry(int original_index); // initialize primary entry 195 void initialize_resolved_reference_index(int ref_index) { 196 assert(_f2 == 0, "set once"); // note: ref_index might be zero also 197 _f2 = ref_index; 198 } 199 200 void set_field( // sets entry to resolved field state 201 Bytecodes::Code get_code, // the bytecode used for reading the field 202 Bytecodes::Code put_code, // the bytecode used for writing the field 203 KlassHandle field_holder, // the object/klass holding the field 204 int orig_field_index, // the original field index in the field holder 205 int field_offset, // the field offset in words in the field holder 206 TosState field_type, // the (machine) field type 207 bool is_final, // the field is final 208 bool is_volatile, // the field is volatile 209 Klass* root_klass // needed by the GC to dirty the klass 210 ); 211 212 void set_method( // sets entry to resolved method entry 213 Bytecodes::Code invoke_code, // the bytecode used for invoking the method 214 methodHandle method, // the method/prototype if any (NULL, otherwise) 215 int vtable_index // the vtable index if any, else negative 216 ); 217 218 void set_interface_call( 219 methodHandle method, // Resolved method 220 int index // Method index into interface 221 ); 222 223 void set_method_handle( 224 methodHandle method, // adapter for invokeExact, etc. 225 Handle appendix, // stored in refs[f2]; could be a java.lang.invoke.MethodType 226 objArrayHandle resolved_references 227 ); 228 229 void set_dynamic_call( 230 methodHandle method, // adapter for this call site 231 Handle appendix, // stored in refs[f2]; could be a java.lang.invoke.CallSite 232 objArrayHandle resolved_references 233 ); 234 235 // Common code for invokedynamic and MH invocations. 236 237 // The "appendix" is an optional call-site-specific parameter which is 238 // pushed by the JVM at the end of the argument list. This argument may 239 // be a MethodType for the MH.invokes and a CallSite for an invokedynamic 240 // instruction. However, its exact type and use depends on the Java upcall, 241 // which simply returns a compiled LambdaForm along with any reference 242 // that LambdaForm needs to complete the call. If the upcall returns a 243 // null appendix, the argument is not passed at all. 244 // 245 // The appendix is *not* represented in the signature of the symbolic 246 // reference for the call site, but (if present) it *is* represented in 247 // the Method* bound to the site. This means that static and dynamic 248 // resolution logic needs to make slightly different assessments about the 249 // number and types of arguments. 250 void set_method_handle_common( 251 Bytecodes::Code invoke_code, // _invokehandle or _invokedynamic 252 methodHandle adapter, // invoker method (f1) 253 Handle appendix, // appendix such as CallSite, MethodType, etc. (refs[f2]) 254 objArrayHandle resolved_references 255 ); 256 257 Method* method_if_resolved(constantPoolHandle cpool); 258 oop appendix_if_resolved(constantPoolHandle cpool); 259 260 void set_parameter_size(int value); 261 262 // Which bytecode number (1 or 2) in the index field is valid for this bytecode? 263 // Returns -1 if neither is valid. 264 static int bytecode_number(Bytecodes::Code code) { 265 switch (code) { 266 case Bytecodes::_getstatic : // fall through 267 case Bytecodes::_getfield : // fall through 268 case Bytecodes::_invokespecial : // fall through 269 case Bytecodes::_invokestatic : // fall through 270 case Bytecodes::_invokeinterface : return 1; 271 case Bytecodes::_putstatic : // fall through 272 case Bytecodes::_putfield : // fall through 273 case Bytecodes::_invokehandle : // fall through 274 case Bytecodes::_invokedynamic : // fall through 275 case Bytecodes::_invokevirtual : return 2; 276 default : break; 277 } 278 return -1; 279 } 280 281 // Has this bytecode been resolved? Only valid for invokes and get/put field/static. 282 bool is_resolved(Bytecodes::Code code) const { 283 switch (bytecode_number(code)) { 284 case 1: return (bytecode_1() == code); 285 case 2: return (bytecode_2() == code); 286 } 287 return false; // default: not resolved 288 } 289 290 // Accessors 291 int indices() const { return _indices; } 292 int constant_pool_index() const { return (indices() & cp_index_mask); } 293 Bytecodes::Code bytecode_1() const { return Bytecodes::cast((indices() >> bytecode_1_shift) & bytecode_1_mask); } 294 Bytecodes::Code bytecode_2() const { return Bytecodes::cast((indices() >> bytecode_2_shift) & bytecode_2_mask); } 295 Method* f1_as_method() const { Metadata* f1 = (Metadata*)_f1; assert(f1 == NULL || f1->is_method(), ""); return (Method*)f1; } 296 Klass* f1_as_klass() const { Metadata* f1 = (Metadata*)_f1; assert(f1 == NULL || f1->is_klass(), ""); return (Klass*)f1; } 297 bool is_f1_null() const { Metadata* f1 = (Metadata*)_f1; return f1 == NULL; } // classifies a CPC entry as unbound 298 int f2_as_index() const { assert(!is_vfinal(), ""); return (int) _f2; } 299 Method* f2_as_vfinal_method() const { assert(is_vfinal(), ""); return (Method*)_f2; } 300 int field_index() const { assert(is_field_entry(), ""); return (_flags & field_index_mask); } 301 int parameter_size() const { assert(is_method_entry(), ""); return (_flags & parameter_size_mask); } 302 bool is_volatile() const { return (_flags & (1 << is_volatile_shift)) != 0; } 303 bool is_final() const { return (_flags & (1 << is_final_shift)) != 0; } 304 bool is_forced_virtual() const { return (_flags & (1 << is_forced_virtual_shift)) != 0; } 305 bool is_vfinal() const { return (_flags & (1 << is_vfinal_shift)) != 0; } 306 bool has_appendix() const { return (_flags & (1 << has_appendix_shift)) != 0; } 307 bool is_method_entry() const { return (_flags & (1 << is_field_entry_shift)) == 0; } 308 bool is_field_entry() const { return (_flags & (1 << is_field_entry_shift)) != 0; } 309 bool is_byte() const { return flag_state() == btos; } 310 bool is_char() const { return flag_state() == ctos; } 311 bool is_short() const { return flag_state() == stos; } 312 bool is_int() const { return flag_state() == itos; } 313 bool is_long() const { return flag_state() == ltos; } 314 bool is_float() const { return flag_state() == ftos; } 315 bool is_double() const { return flag_state() == dtos; } 316 bool is_object() const { return flag_state() == atos; } 317 TosState flag_state() const { assert((uint)number_of_states <= (uint)tos_state_mask+1, ""); 318 return (TosState)((_flags >> tos_state_shift) & tos_state_mask); } 319 320 // Code generation support 321 static WordSize size() { return in_WordSize(sizeof(ConstantPoolCacheEntry) / HeapWordSize); } 322 static ByteSize size_in_bytes() { return in_ByteSize(sizeof(ConstantPoolCacheEntry)); } 323 static ByteSize indices_offset() { return byte_offset_of(ConstantPoolCacheEntry, _indices); } 324 static ByteSize f1_offset() { return byte_offset_of(ConstantPoolCacheEntry, _f1); } 325 static ByteSize f2_offset() { return byte_offset_of(ConstantPoolCacheEntry, _f2); } 326 static ByteSize flags_offset() { return byte_offset_of(ConstantPoolCacheEntry, _flags); } 327 328 // RedefineClasses() API support: 329 // If this constantPoolCacheEntry refers to old_method then update it 330 // to refer to new_method. 331 // trace_name_printed is set to true if the current call has 332 // printed the klass name so that other routines in the adjust_* 333 // group don't print the klass name. 334 bool adjust_method_entry(Method* old_method, Method* new_method, 335 bool * trace_name_printed); 336 NOT_PRODUCT(bool check_no_old_entries();) 337 bool is_interesting_method_entry(Klass* k); 338 339 // Debugging & Printing 340 void print (outputStream* st, int index) const; 341 void verify(outputStream* st) const; 342 343 static void verify_tos_state_shift() { 344 // When shifting flags as a 32-bit int, make sure we don't need an extra mask for tos_state: 345 assert((((u4)-1 >> tos_state_shift) & ~tos_state_mask) == 0, "no need for tos_state mask"); 346 } 347}; 348 349 350// A constant pool cache is a runtime data structure set aside to a constant pool. The cache 351// holds interpreter runtime information for all field access and invoke bytecodes. The cache 352// is created and initialized before a class is actively used (i.e., initialized), the indivi- 353// dual cache entries are filled at resolution (i.e., "link") time (see also: rewriter.*). 354 355class ConstantPoolCache: public MetaspaceObj { 356 friend class VMStructs; 357 friend class MetadataFactory; 358 private: 359 int _length; 360 ConstantPool* _constant_pool; // the corresponding constant pool 361 362 // Sizing 363 debug_only(friend class ClassVerifier;) 364 365 // Constructor 366 ConstantPoolCache(int length) : _length(length), _constant_pool(NULL) { 367 for (int i = 0; i < length; i++) { 368 assert(entry_at(i)->is_f1_null(), "Failed to clear?"); 369 } 370 } 371 372 public: 373 static ConstantPoolCache* allocate(ClassLoaderData* loader_data, int length, TRAPS); 374 bool is_constantPoolCache() const { return true; } 375 376 int length() const { return _length; } 377 private: 378 void set_length(int length) { _length = length; } 379 380 static int header_size() { return sizeof(ConstantPoolCache) / HeapWordSize; } 381 static int size(int length) { return align_object_size(header_size() + length * in_words(ConstantPoolCacheEntry::size())); } 382 public: 383 int size() const { return size(length()); } 384 private: 385 386 // Helpers 387 ConstantPool** constant_pool_addr() { return &_constant_pool; } 388 ConstantPoolCacheEntry* base() const { return (ConstantPoolCacheEntry*)((address)this + in_bytes(base_offset())); } 389 390 friend class constantPoolCacheKlass; 391 friend class ConstantPoolCacheEntry; 392 393 public: 394 // Initialization 395 void initialize(intArray& inverse_index_map, intArray& invokedynamic_references_map); 396 397 // Accessors 398 void set_constant_pool(ConstantPool* pool) { _constant_pool = pool; } 399 ConstantPool* constant_pool() const { return _constant_pool; } 400 // Fetches the entry at the given index. 401 // In either case the index must not be encoded or byte-swapped in any way. 402 ConstantPoolCacheEntry* entry_at(int i) const { 403 assert(0 <= i && i < length(), "index out of bounds"); 404 return base() + i; 405 } 406 407 // Code generation 408 static ByteSize base_offset() { return in_ByteSize(sizeof(ConstantPoolCache)); } 409 static ByteSize entry_offset(int raw_index) { 410 int index = raw_index; 411 return (base_offset() + ConstantPoolCacheEntry::size_in_bytes() * index); 412 } 413 414 // RedefineClasses() API support: 415 // If any entry of this constantPoolCache points to any of 416 // old_methods, replace it with the corresponding new_method. 417 // trace_name_printed is set to true if the current call has 418 // printed the klass name so that other routines in the adjust_* 419 // group don't print the klass name. 420 void adjust_method_entries(Method** old_methods, Method** new_methods, 421 int methods_length, bool * trace_name_printed); 422 NOT_PRODUCT(bool check_no_old_entries();) 423 424 // Deallocate - no fields to deallocate 425 DEBUG_ONLY(bool on_stack() { return false; }) 426 void deallocate_contents(ClassLoaderData* data) {} 427 bool is_klass() const { return false; } 428 429 // Printing 430 void print_on(outputStream* st) const; 431 void print_value_on(outputStream* st) const; 432 433 const char* internal_name() const { return "{constant pool cache}"; } 434 435 // Verify 436 void verify_on(outputStream* st); 437}; 438 439#endif // SHARE_VM_OOPS_CPCACHEOOP_HPP 440