1 /* 2 * Copyright (c) 1998, 2010, 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 #include "precompiled.hpp" 26 #include "gc_implementation/shared/markSweep.inline.hpp" 27 #include "interpreter/interpreter.hpp" 28 #include "interpreter/rewriter.hpp" 29 #include "memory/universe.inline.hpp" 30 #include "oops/cpCacheOop.hpp" 31 #include "oops/objArrayOop.hpp" 32 #include "oops/oop.inline.hpp" 33 #include "prims/jvmtiRedefineClassesTrace.hpp" 34 #include "runtime/handles.inline.hpp" 35 36 37 // Implememtation of ConstantPoolCacheEntry 38 39 void ConstantPoolCacheEntry::initialize_entry(int index) { 40 assert(0 < index && index < 0x10000, "sanity check"); 41 _indices = index; 42 assert(constant_pool_index() == index, ""); 43 } 44 45 void ConstantPoolCacheEntry::initialize_secondary_entry(int main_index) { 46 assert(0 <= main_index && main_index < 0x10000, "sanity check"); 47 _indices = (main_index << 16); 48 assert(main_entry_index() == main_index, ""); 49 } 50 51 int ConstantPoolCacheEntry::as_flags(TosState state, bool is_final, 52 bool is_vfinal, bool is_volatile, 53 bool is_method_interface, bool is_method) { 54 int f = state; 55 56 assert( state < number_of_states, "Invalid state in as_flags"); 57 58 f <<= 1; 59 if (is_final) f |= 1; 60 f <<= 1; 61 if (is_vfinal) f |= 1; 62 f <<= 1; 63 if (is_volatile) f |= 1; 64 f <<= 1; 65 if (is_method_interface) f |= 1; 66 f <<= 1; 67 if (is_method) f |= 1; 68 f <<= ConstantPoolCacheEntry::hotSwapBit; 69 // Preserve existing flag bit values 70 #ifdef ASSERT 71 int old_state = ((_flags >> tosBits) & 0x0F); 72 assert(old_state == 0 || old_state == state, 73 "inconsistent cpCache flags state"); 74 #endif 75 return (_flags | f) ; 76 } 77 78 void ConstantPoolCacheEntry::set_bytecode_1(Bytecodes::Code code) { 79 #ifdef ASSERT 80 // Read once. 81 volatile Bytecodes::Code c = bytecode_1(); 82 assert(c == 0 || c == code || code == 0, "update must be consistent"); 83 #endif 84 // Need to flush pending stores here before bytecode is written. 85 OrderAccess::release_store_ptr(&_indices, _indices | ((u_char)code << 16)); 86 } 87 88 void ConstantPoolCacheEntry::set_bytecode_2(Bytecodes::Code code) { 89 #ifdef ASSERT 90 // Read once. 91 volatile Bytecodes::Code c = bytecode_2(); 92 assert(c == 0 || c == code || code == 0, "update must be consistent"); 93 #endif 94 // Need to flush pending stores here before bytecode is written. 95 OrderAccess::release_store_ptr(&_indices, _indices | ((u_char)code << 24)); 96 } 97 98 #ifdef ASSERT 99 // It is possible to have two different dummy methodOops created 100 // when the resolve code for invoke interface executes concurrently 101 // Hence the assertion below is weakened a bit for the invokeinterface 102 // case. 103 bool ConstantPoolCacheEntry::same_methodOop(oop cur_f1, oop f1) { 104 return (cur_f1 == f1 || ((methodOop)cur_f1)->name() == 105 ((methodOop)f1)->name() || ((methodOop)cur_f1)->signature() == 106 ((methodOop)f1)->signature()); 107 } 108 #endif 109 110 // Note that concurrent update of both bytecodes can leave one of them 111 // reset to zero. This is harmless; the interpreter will simply re-resolve 112 // the damaged entry. More seriously, the memory synchronization is needed 113 // to flush other fields (f1, f2) completely to memory before the bytecodes 114 // are updated, lest other processors see a non-zero bytecode but zero f1/f2. 115 void ConstantPoolCacheEntry::set_field(Bytecodes::Code get_code, 116 Bytecodes::Code put_code, 117 KlassHandle field_holder, 118 int orig_field_index, 119 int field_offset, 120 TosState field_type, 121 bool is_final, 122 bool is_volatile) { 123 set_f1(field_holder()); 124 set_f2(field_offset); 125 // The field index is used by jvm/ti and is the index into fields() array 126 // in holder instanceKlass. This is scaled by instanceKlass::next_offset. 127 assert((orig_field_index % instanceKlass::next_offset) == 0, "wierd index"); 128 const int field_index = orig_field_index / instanceKlass::next_offset; 129 assert(field_index <= field_index_mask, 130 "field index does not fit in low flag bits"); 131 set_flags(as_flags(field_type, is_final, false, is_volatile, false, false) | 132 (field_index & field_index_mask)); 133 set_bytecode_1(get_code); 134 set_bytecode_2(put_code); 135 NOT_PRODUCT(verify(tty)); 136 } 137 138 int ConstantPoolCacheEntry::field_index() const { 139 return (_flags & field_index_mask) * instanceKlass::next_offset; 140 } 141 142 void ConstantPoolCacheEntry::set_method(Bytecodes::Code invoke_code, 143 methodHandle method, 144 int vtable_index) { 145 assert(!is_secondary_entry(), ""); 146 assert(method->interpreter_entry() != NULL, "should have been set at this point"); 147 assert(!method->is_obsolete(), "attempt to write obsolete method to cpCache"); 148 bool change_to_virtual = (invoke_code == Bytecodes::_invokeinterface); 149 150 int byte_no = -1; 151 bool needs_vfinal_flag = false; 152 switch (invoke_code) { 153 case Bytecodes::_invokevirtual: 154 case Bytecodes::_invokeinterface: { 155 if (method->can_be_statically_bound()) { 156 set_f2((intptr_t)method()); 157 needs_vfinal_flag = true; 158 } else { 159 assert(vtable_index >= 0, "valid index"); 160 set_f2(vtable_index); 161 } 162 byte_no = 2; 163 break; 164 } 165 166 case Bytecodes::_invokedynamic: // similar to _invokevirtual 167 if (TraceInvokeDynamic) { 168 tty->print_cr("InvokeDynamic set_method%s method="PTR_FORMAT" index=%d", 169 (is_secondary_entry() ? " secondary" : ""), 170 (intptr_t)method(), vtable_index); 171 method->print(); 172 this->print(tty, 0); 173 } 174 assert(method->can_be_statically_bound(), "must be a MH invoker method"); 175 assert(AllowTransitionalJSR292 || _f2 >= constantPoolOopDesc::CPCACHE_INDEX_TAG, "BSM index initialized"); 176 set_f1(method()); 177 needs_vfinal_flag = false; // _f2 is not an oop 178 assert(!is_vfinal(), "f2 not an oop"); 179 byte_no = 1; // coordinate this with bytecode_number & is_resolved 180 break; 181 182 case Bytecodes::_invokespecial: 183 // Preserve the value of the vfinal flag on invokevirtual bytecode 184 // which may be shared with this constant pool cache entry. 185 needs_vfinal_flag = is_resolved(Bytecodes::_invokevirtual) && is_vfinal(); 186 // fall through 187 case Bytecodes::_invokestatic: 188 set_f1(method()); 189 byte_no = 1; 190 break; 191 default: 192 ShouldNotReachHere(); 193 break; 194 } 195 196 set_flags(as_flags(as_TosState(method->result_type()), 197 method->is_final_method(), 198 needs_vfinal_flag, 199 false, 200 change_to_virtual, 201 true)| 202 method()->size_of_parameters()); 203 204 // Note: byte_no also appears in TemplateTable::resolve. 205 if (byte_no == 1) { 206 set_bytecode_1(invoke_code); 207 } else if (byte_no == 2) { 208 if (change_to_virtual) { 209 // NOTE: THIS IS A HACK - BE VERY CAREFUL!!! 210 // 211 // Workaround for the case where we encounter an invokeinterface, but we 212 // should really have an _invokevirtual since the resolved method is a 213 // virtual method in java.lang.Object. This is a corner case in the spec 214 // but is presumably legal. javac does not generate this code. 215 // 216 // We set bytecode_1() to _invokeinterface, because that is the 217 // bytecode # used by the interpreter to see if it is resolved. 218 // We set bytecode_2() to _invokevirtual. 219 // See also interpreterRuntime.cpp. (8/25/2000) 220 // Only set resolved for the invokeinterface case if method is public. 221 // Otherwise, the method needs to be reresolved with caller for each 222 // interface call. 223 if (method->is_public()) set_bytecode_1(invoke_code); 224 set_bytecode_2(Bytecodes::_invokevirtual); 225 } else { 226 set_bytecode_2(invoke_code); 227 } 228 } else { 229 ShouldNotReachHere(); 230 } 231 NOT_PRODUCT(verify(tty)); 232 } 233 234 235 void ConstantPoolCacheEntry::set_interface_call(methodHandle method, int index) { 236 assert(!is_secondary_entry(), ""); 237 klassOop interf = method->method_holder(); 238 assert(instanceKlass::cast(interf)->is_interface(), "must be an interface"); 239 set_f1(interf); 240 set_f2(index); 241 set_flags(as_flags(as_TosState(method->result_type()), method->is_final_method(), false, false, false, true) | method()->size_of_parameters()); 242 set_bytecode_1(Bytecodes::_invokeinterface); 243 } 244 245 246 void ConstantPoolCacheEntry::initialize_bootstrap_method_index_in_cache(int bsm_cache_index) { 247 assert(!is_secondary_entry(), "only for JVM_CONSTANT_InvokeDynamic main entry"); 248 assert(_f2 == 0, "initialize once"); 249 assert(bsm_cache_index == (int)(u2)bsm_cache_index, "oob"); 250 set_f2(bsm_cache_index + constantPoolOopDesc::CPCACHE_INDEX_TAG); 251 } 252 253 int ConstantPoolCacheEntry::bootstrap_method_index_in_cache() { 254 assert(!is_secondary_entry(), "only for JVM_CONSTANT_InvokeDynamic main entry"); 255 intptr_t bsm_cache_index = (intptr_t) _f2 - constantPoolOopDesc::CPCACHE_INDEX_TAG; 256 assert(bsm_cache_index == (intptr_t)(u2)bsm_cache_index, "oob"); 257 return (int) bsm_cache_index; 258 } 259 260 void ConstantPoolCacheEntry::set_dynamic_call(Handle call_site, 261 methodHandle signature_invoker) { 262 assert(is_secondary_entry(), ""); 263 int param_size = signature_invoker->size_of_parameters(); 264 assert(param_size >= 1, "method argument size must include MH.this"); 265 param_size -= 1; // do not count MH.this; it is not stacked for invokedynamic 266 if (Atomic::cmpxchg_ptr(call_site(), &_f1, NULL) == NULL) { 267 // racing threads might be trying to install their own favorites 268 set_f1(call_site()); 269 } 270 bool is_final = true; 271 assert(signature_invoker->is_final_method(), "is_final"); 272 set_flags(as_flags(as_TosState(signature_invoker->result_type()), is_final, false, false, false, true) | param_size); 273 // do not do set_bytecode on a secondary CP cache entry 274 //set_bytecode_1(Bytecodes::_invokedynamic); 275 } 276 277 278 class LocalOopClosure: public OopClosure { 279 private: 280 void (*_f)(oop*); 281 282 public: 283 LocalOopClosure(void f(oop*)) { _f = f; } 284 virtual void do_oop(oop* o) { _f(o); } 285 virtual void do_oop(narrowOop *o) { ShouldNotReachHere(); } 286 }; 287 288 289 void ConstantPoolCacheEntry::oops_do(void f(oop*)) { 290 LocalOopClosure blk(f); 291 oop_iterate(&blk); 292 } 293 294 295 void ConstantPoolCacheEntry::oop_iterate(OopClosure* blk) { 296 assert(in_words(size()) == 4, "check code below - may need adjustment"); 297 // field[1] is always oop or NULL 298 blk->do_oop((oop*)&_f1); 299 if (is_vfinal()) { 300 blk->do_oop((oop*)&_f2); 301 } 302 } 303 304 305 void ConstantPoolCacheEntry::oop_iterate_m(OopClosure* blk, MemRegion mr) { 306 assert(in_words(size()) == 4, "check code below - may need adjustment"); 307 // field[1] is always oop or NULL 308 if (mr.contains((oop *)&_f1)) blk->do_oop((oop*)&_f1); 309 if (is_vfinal()) { 310 if (mr.contains((oop *)&_f2)) blk->do_oop((oop*)&_f2); 311 } 312 } 313 314 315 void ConstantPoolCacheEntry::follow_contents() { 316 assert(in_words(size()) == 4, "check code below - may need adjustment"); 317 // field[1] is always oop or NULL 318 MarkSweep::mark_and_push((oop*)&_f1); 319 if (is_vfinal()) { 320 MarkSweep::mark_and_push((oop*)&_f2); 321 } 322 } 323 324 #ifndef SERIALGC 325 void ConstantPoolCacheEntry::follow_contents(ParCompactionManager* cm) { 326 assert(in_words(size()) == 4, "check code below - may need adjustment"); 327 // field[1] is always oop or NULL 328 PSParallelCompact::mark_and_push(cm, (oop*)&_f1); 329 if (is_vfinal()) { 330 PSParallelCompact::mark_and_push(cm, (oop*)&_f2); 331 } 332 } 333 #endif // SERIALGC 334 335 void ConstantPoolCacheEntry::adjust_pointers() { 336 assert(in_words(size()) == 4, "check code below - may need adjustment"); 337 // field[1] is always oop or NULL 338 MarkSweep::adjust_pointer((oop*)&_f1); 339 if (is_vfinal()) { 340 MarkSweep::adjust_pointer((oop*)&_f2); 341 } 342 } 343 344 #ifndef SERIALGC 345 void ConstantPoolCacheEntry::update_pointers() { 346 assert(in_words(size()) == 4, "check code below - may need adjustment"); 347 // field[1] is always oop or NULL 348 PSParallelCompact::adjust_pointer((oop*)&_f1); 349 if (is_vfinal()) { 350 PSParallelCompact::adjust_pointer((oop*)&_f2); 351 } 352 } 353 354 void ConstantPoolCacheEntry::update_pointers(HeapWord* beg_addr, 355 HeapWord* end_addr) { 356 assert(in_words(size()) == 4, "check code below - may need adjustment"); 357 // field[1] is always oop or NULL 358 PSParallelCompact::adjust_pointer((oop*)&_f1, beg_addr, end_addr); 359 if (is_vfinal()) { 360 PSParallelCompact::adjust_pointer((oop*)&_f2, beg_addr, end_addr); 361 } 362 } 363 #endif // SERIALGC 364 365 // RedefineClasses() API support: 366 // If this constantPoolCacheEntry refers to old_method then update it 367 // to refer to new_method. 368 bool ConstantPoolCacheEntry::adjust_method_entry(methodOop old_method, 369 methodOop new_method, bool * trace_name_printed) { 370 371 if (is_vfinal()) { 372 // virtual and final so f2() contains method ptr instead of vtable index 373 if (f2() == (intptr_t)old_method) { 374 // match old_method so need an update 375 _f2 = (intptr_t)new_method; 376 if (RC_TRACE_IN_RANGE(0x00100000, 0x00400000)) { 377 if (!(*trace_name_printed)) { 378 // RC_TRACE_MESG macro has an embedded ResourceMark 379 RC_TRACE_MESG(("adjust: name=%s", 380 Klass::cast(old_method->method_holder())->external_name())); 381 *trace_name_printed = true; 382 } 383 // RC_TRACE macro has an embedded ResourceMark 384 RC_TRACE(0x00400000, ("cpc vf-entry update: %s(%s)", 385 new_method->name()->as_C_string(), 386 new_method->signature()->as_C_string())); 387 } 388 389 return true; 390 } 391 392 // f1() is not used with virtual entries so bail out 393 return false; 394 } 395 396 if ((oop)_f1 == NULL) { 397 // NULL f1() means this is a virtual entry so bail out 398 // We are assuming that the vtable index does not need change. 399 return false; 400 } 401 402 if ((oop)_f1 == old_method) { 403 _f1 = new_method; 404 if (RC_TRACE_IN_RANGE(0x00100000, 0x00400000)) { 405 if (!(*trace_name_printed)) { 406 // RC_TRACE_MESG macro has an embedded ResourceMark 407 RC_TRACE_MESG(("adjust: name=%s", 408 Klass::cast(old_method->method_holder())->external_name())); 409 *trace_name_printed = true; 410 } 411 // RC_TRACE macro has an embedded ResourceMark 412 RC_TRACE(0x00400000, ("cpc entry update: %s(%s)", 413 new_method->name()->as_C_string(), 414 new_method->signature()->as_C_string())); 415 } 416 417 return true; 418 } 419 420 return false; 421 } 422 423 bool ConstantPoolCacheEntry::is_interesting_method_entry(klassOop k) { 424 if (!is_method_entry()) { 425 // not a method entry so not interesting by default 426 return false; 427 } 428 429 methodOop m = NULL; 430 if (is_vfinal()) { 431 // virtual and final so _f2 contains method ptr instead of vtable index 432 m = (methodOop)_f2; 433 } else if ((oop)_f1 == NULL) { 434 // NULL _f1 means this is a virtual entry so also not interesting 435 return false; 436 } else { 437 if (!((oop)_f1)->is_method()) { 438 // _f1 can also contain a klassOop for an interface 439 return false; 440 } 441 m = (methodOop)_f1; 442 } 443 444 assert(m != NULL && m->is_method(), "sanity check"); 445 if (m == NULL || !m->is_method() || m->method_holder() != k) { 446 // robustness for above sanity checks or method is not in 447 // the interesting class 448 return false; 449 } 450 451 // the method is in the interesting class so the entry is interesting 452 return true; 453 } 454 455 void ConstantPoolCacheEntry::print(outputStream* st, int index) const { 456 // print separator 457 if (index == 0) tty->print_cr(" -------------"); 458 // print entry 459 tty->print("%3d ("PTR_FORMAT") ", index, (intptr_t)this); 460 if (is_secondary_entry()) 461 tty->print_cr("[%5d|secondary]", main_entry_index()); 462 else 463 tty->print_cr("[%02x|%02x|%5d]", bytecode_2(), bytecode_1(), constant_pool_index()); 464 tty->print_cr(" [ "PTR_FORMAT"]", (intptr_t)(oop)_f1); 465 tty->print_cr(" [ "PTR_FORMAT"]", (intptr_t)_f2); 466 tty->print_cr(" [ "PTR_FORMAT"]", (intptr_t)_flags); 467 tty->print_cr(" -------------"); 468 } 469 470 void ConstantPoolCacheEntry::verify(outputStream* st) const { 471 // not implemented yet 472 } 473 474 // Implementation of ConstantPoolCache 475 476 void constantPoolCacheOopDesc::initialize(intArray& inverse_index_map) { 477 assert(inverse_index_map.length() == length(), "inverse index map must have same length as cache"); 478 for (int i = 0; i < length(); i++) { 479 ConstantPoolCacheEntry* e = entry_at(i); 480 int original_index = inverse_index_map[i]; 481 if ((original_index & Rewriter::_secondary_entry_tag) != 0) { 482 int main_index = (original_index - Rewriter::_secondary_entry_tag); 483 assert(!entry_at(main_index)->is_secondary_entry(), "valid main index"); 484 e->initialize_secondary_entry(main_index); 485 } else { 486 e->initialize_entry(original_index); 487 } 488 assert(entry_at(i) == e, "sanity"); 489 } 490 } 491 492 // RedefineClasses() API support: 493 // If any entry of this constantPoolCache points to any of 494 // old_methods, replace it with the corresponding new_method. 495 void constantPoolCacheOopDesc::adjust_method_entries(methodOop* old_methods, methodOop* new_methods, 496 int methods_length, bool * trace_name_printed) { 497 498 if (methods_length == 0) { 499 // nothing to do if there are no methods 500 return; 501 } 502 503 // get shorthand for the interesting class 504 klassOop old_holder = old_methods[0]->method_holder(); 505 506 for (int i = 0; i < length(); i++) { 507 if (!entry_at(i)->is_interesting_method_entry(old_holder)) { 508 // skip uninteresting methods 509 continue; 510 } 511 512 // The constantPoolCache contains entries for several different 513 // things, but we only care about methods. In fact, we only care 514 // about methods in the same class as the one that contains the 515 // old_methods. At this point, we have an interesting entry. 516 517 for (int j = 0; j < methods_length; j++) { 518 methodOop old_method = old_methods[j]; 519 methodOop new_method = new_methods[j]; 520 521 if (entry_at(i)->adjust_method_entry(old_method, new_method, 522 trace_name_printed)) { 523 // current old_method matched this entry and we updated it so 524 // break out and get to the next interesting entry if there one 525 break; 526 } 527 } 528 } 529 }