1 /*
   2  * Copyright (c) 1998, 2014, 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/cpCache.hpp"
  31 #include "oops/objArrayOop.hpp"
  32 #include "oops/oop.inline.hpp"
  33 #include "prims/jvmtiRedefineClassesTrace.hpp"
  34 #include "prims/methodHandles.hpp"
  35 #include "runtime/atomic.inline.hpp"
  36 #include "runtime/handles.inline.hpp"
  37 #include "runtime/orderAccess.inline.hpp"
  38 #include "utilities/macros.hpp"
  39 #if INCLUDE_ALL_GCS
  40 # include "gc_implementation/parallelScavenge/psPromotionManager.hpp"
  41 #endif // INCLUDE_ALL_GCS
  42 
  43 PRAGMA_FORMAT_MUTE_WARNINGS_FOR_GCC
  44 
  45 // Implementation of ConstantPoolCacheEntry
  46 
  47 void ConstantPoolCacheEntry::initialize_entry(int index) {
  48   assert(0 < index && index < 0x10000, "sanity check");
  49   _indices = index;
  50   _f1 = NULL;
  51   _f2 = _flags = 0;
  52   assert(constant_pool_index() == index, "");
  53 }
  54 
  55 int ConstantPoolCacheEntry::make_flags(TosState state,
  56                                        int option_bits,
  57                                        int field_index_or_method_params) {
  58   assert(state < number_of_states, "Invalid state in make_flags");
  59   int f = ((int)state << tos_state_shift) | option_bits | field_index_or_method_params;
  60   // Preserve existing flag bit values
  61   // The low bits are a field offset, or else the method parameter size.
  62 #ifdef ASSERT
  63   TosState old_state = flag_state();
  64   assert(old_state == (TosState)0 || old_state == state,
  65          "inconsistent cpCache flags state");
  66 #endif
  67   return (_flags | f) ;
  68 }
  69 
  70 void ConstantPoolCacheEntry::set_bytecode_1(Bytecodes::Code code) {
  71 #ifdef ASSERT
  72   // Read once.
  73   volatile Bytecodes::Code c = bytecode_1();
  74   assert(c == 0 || c == code || code == 0, "update must be consistent");
  75 #endif
  76   // Need to flush pending stores here before bytecode is written.
  77   OrderAccess::release_store_ptr(&_indices, _indices | ((u_char)code << bytecode_1_shift));
  78 }
  79 
  80 void ConstantPoolCacheEntry::set_bytecode_2(Bytecodes::Code code) {
  81 #ifdef ASSERT
  82   // Read once.
  83   volatile Bytecodes::Code c = bytecode_2();
  84   assert(c == 0 || c == code || code == 0, "update must be consistent");
  85 #endif
  86   // Need to flush pending stores here before bytecode is written.
  87   OrderAccess::release_store_ptr(&_indices, _indices | ((u_char)code << bytecode_2_shift));
  88 }
  89 
  90 // Sets f1, ordering with previous writes.
  91 void ConstantPoolCacheEntry::release_set_f1(Metadata* f1) {
  92   assert(f1 != NULL, "");
  93   OrderAccess::release_store_ptr((HeapWord*) &_f1, f1);
  94 }
  95 
  96 // Sets flags, but only if the value was previously zero.
  97 bool ConstantPoolCacheEntry::init_flags_atomic(intptr_t flags) {
  98   intptr_t result = Atomic::cmpxchg_ptr(flags, &_flags, 0);
  99   return (result == 0);
 100 }
 101 
 102 // Note that concurrent update of both bytecodes can leave one of them
 103 // reset to zero.  This is harmless; the interpreter will simply re-resolve
 104 // the damaged entry.  More seriously, the memory synchronization is needed
 105 // to flush other fields (f1, f2) completely to memory before the bytecodes
 106 // are updated, lest other processors see a non-zero bytecode but zero f1/f2.
 107 void ConstantPoolCacheEntry::set_field(Bytecodes::Code get_code,
 108                                        Bytecodes::Code put_code,
 109                                        KlassHandle field_holder,
 110                                        int field_index,
 111                                        int field_offset,
 112                                        TosState field_type,
 113                                        bool is_final,
 114                                        bool is_volatile,
 115                                        Klass* root_klass) {
 116   set_f1(field_holder());
 117   set_f2(field_offset);
 118   assert((field_index & field_index_mask) == field_index,
 119          "field index does not fit in low flag bits");
 120   set_field_flags(field_type,
 121                   ((is_volatile ? 1 : 0) << is_volatile_shift) |
 122                   ((is_final    ? 1 : 0) << is_final_shift),
 123                   field_index);
 124   set_bytecode_1(get_code);
 125   set_bytecode_2(put_code);
 126   NOT_PRODUCT(verify(tty));
 127 }
 128 
 129 void ConstantPoolCacheEntry::set_parameter_size(int value) {
 130   // This routine is called only in corner cases where the CPCE is not yet initialized.
 131   // See AbstractInterpreter::deopt_continue_after_entry.
 132   assert(_flags == 0 || parameter_size() == 0 || parameter_size() == value,
 133          err_msg("size must not change: parameter_size=%d, value=%d", parameter_size(), value));
 134   // Setting the parameter size by itself is only safe if the
 135   // current value of _flags is 0, otherwise another thread may have
 136   // updated it and we don't want to overwrite that value.  Don't
 137   // bother trying to update it once it's nonzero but always make
 138   // sure that the final parameter size agrees with what was passed.
 139   if (_flags == 0) {
 140     Atomic::cmpxchg_ptr((value & parameter_size_mask), &_flags, 0);
 141   }
 142   guarantee(parameter_size() == value,
 143             err_msg("size must not change: parameter_size=%d, value=%d", parameter_size(), value));
 144 }
 145 
 146 void ConstantPoolCacheEntry::set_direct_or_vtable_call(Bytecodes::Code invoke_code,
 147                                                        methodHandle method,
 148                                                        int vtable_index) {
 149   bool is_vtable_call = (vtable_index >= 0);  // FIXME: split this method on this boolean
 150   assert(method->interpreter_entry() != NULL, "should have been set at this point");
 151   assert(!method->is_obsolete(),  "attempt to write obsolete method to cpCache");
 152 
 153   int byte_no = -1;
 154   bool change_to_virtual = false;
 155 
 156   switch (invoke_code) {
 157     case Bytecodes::_invokeinterface:
 158       // We get here from InterpreterRuntime::resolve_invoke when an invokeinterface
 159       // instruction somehow links to a non-interface method (in Object).
 160       // In that case, the method has no itable index and must be invoked as a virtual.
 161       // Set a flag to keep track of this corner case.
 162       change_to_virtual = true;
 163 
 164       // ...and fall through as if we were handling invokevirtual:
 165     case Bytecodes::_invokevirtual:
 166       {
 167         if (!is_vtable_call) {
 168           assert(method->can_be_statically_bound(), "");
 169           // set_f2_as_vfinal_method checks if is_vfinal flag is true.
 170           set_method_flags(as_TosState(method->result_type()),
 171                            (                             1      << is_vfinal_shift) |
 172                            ((method->is_final_method() ? 1 : 0) << is_final_shift)  |
 173                            ((change_to_virtual         ? 1 : 0) << is_forced_virtual_shift),
 174                            method()->size_of_parameters());
 175           set_f2_as_vfinal_method(method());
 176         } else {
 177           assert(!method->can_be_statically_bound(), "");
 178           assert(vtable_index >= 0, "valid index");
 179           assert(!method->is_final_method(), "sanity");
 180           set_method_flags(as_TosState(method->result_type()),
 181                            ((change_to_virtual ? 1 : 0) << is_forced_virtual_shift),
 182                            method()->size_of_parameters());
 183           set_f2(vtable_index);
 184         }
 185         byte_no = 2;
 186         break;
 187       }
 188 
 189     case Bytecodes::_invokespecial:
 190     case Bytecodes::_invokestatic:
 191       assert(!is_vtable_call, "");
 192       // Note:  Read and preserve the value of the is_vfinal flag on any
 193       // invokevirtual bytecode shared with this constant pool cache entry.
 194       // It is cheap and safe to consult is_vfinal() at all times.
 195       // Once is_vfinal is set, it must stay that way, lest we get a dangling oop.
 196       set_method_flags(as_TosState(method->result_type()),
 197                        ((is_vfinal()               ? 1 : 0) << is_vfinal_shift) |
 198                        ((method->is_final_method() ? 1 : 0) << is_final_shift),
 199                        method()->size_of_parameters());
 200       set_f1(method());
 201       byte_no = 1;
 202       break;
 203     default:
 204       ShouldNotReachHere();
 205       break;
 206   }
 207 
 208   // Note:  byte_no also appears in TemplateTable::resolve.
 209   if (byte_no == 1) {
 210     assert(invoke_code != Bytecodes::_invokevirtual &&
 211            invoke_code != Bytecodes::_invokeinterface, "");
 212     set_bytecode_1(invoke_code);
 213   } else if (byte_no == 2)  {
 214     if (change_to_virtual) {
 215       assert(invoke_code == Bytecodes::_invokeinterface, "");
 216       // NOTE: THIS IS A HACK - BE VERY CAREFUL!!!
 217       //
 218       // Workaround for the case where we encounter an invokeinterface, but we
 219       // should really have an _invokevirtual since the resolved method is a
 220       // virtual method in java.lang.Object. This is a corner case in the spec
 221       // but is presumably legal. javac does not generate this code.
 222       //
 223       // We set bytecode_1() to _invokeinterface, because that is the
 224       // bytecode # used by the interpreter to see if it is resolved.
 225       // We set bytecode_2() to _invokevirtual.
 226       // See also interpreterRuntime.cpp. (8/25/2000)
 227       // Only set resolved for the invokeinterface case if method is public.
 228       // Otherwise, the method needs to be reresolved with caller for each
 229       // interface call.
 230       if (method->is_public()) set_bytecode_1(invoke_code);
 231     } else {
 232       assert(invoke_code == Bytecodes::_invokevirtual, "");
 233     }
 234     // set up for invokevirtual, even if linking for invokeinterface also:
 235     set_bytecode_2(Bytecodes::_invokevirtual);
 236   } else {
 237     ShouldNotReachHere();
 238   }
 239   NOT_PRODUCT(verify(tty));
 240 }
 241 
 242 void ConstantPoolCacheEntry::set_direct_call(Bytecodes::Code invoke_code, methodHandle method) {
 243   int index = Method::nonvirtual_vtable_index;
 244   // index < 0; FIXME: inline and customize set_direct_or_vtable_call
 245   set_direct_or_vtable_call(invoke_code, method, index);
 246 }
 247 
 248 void ConstantPoolCacheEntry::set_vtable_call(Bytecodes::Code invoke_code, methodHandle method, int index) {
 249   // either the method is a miranda or its holder should accept the given index
 250   assert(method->method_holder()->is_interface() || method->method_holder()->verify_vtable_index(index), "");
 251   // index >= 0; FIXME: inline and customize set_direct_or_vtable_call
 252   set_direct_or_vtable_call(invoke_code, method, index);
 253 }
 254 
 255 void ConstantPoolCacheEntry::set_itable_call(Bytecodes::Code invoke_code, methodHandle method, int index) {
 256   assert(method->method_holder()->verify_itable_index(index), "");
 257   assert(invoke_code == Bytecodes::_invokeinterface, "");
 258   InstanceKlass* interf = method->method_holder();
 259   assert(interf->is_interface(), "must be an interface");
 260   assert(!method->is_final_method(), "interfaces do not have final methods; cannot link to one here");
 261   set_f1(interf);
 262   set_f2(index);
 263   set_method_flags(as_TosState(method->result_type()),
 264                    0,  // no option bits
 265                    method()->size_of_parameters());
 266   set_bytecode_1(Bytecodes::_invokeinterface);
 267 }
 268 
 269 
 270 void ConstantPoolCacheEntry::set_method_handle(constantPoolHandle cpool, const CallInfo &call_info) {
 271   set_method_handle_common(cpool, Bytecodes::_invokehandle, call_info);
 272 }
 273 
 274 void ConstantPoolCacheEntry::set_dynamic_call(constantPoolHandle cpool, const CallInfo &call_info) {
 275   set_method_handle_common(cpool, Bytecodes::_invokedynamic, call_info);
 276 }
 277 
 278 void ConstantPoolCacheEntry::set_method_handle_common(constantPoolHandle cpool,
 279                                                       Bytecodes::Code invoke_code,
 280                                                       const CallInfo &call_info) {
 281   // NOTE: This CPCE can be the subject of data races.
 282   // There are three words to update: flags, refs[f2], f1 (in that order).
 283   // Writers must store all other values before f1.
 284   // Readers must test f1 first for non-null before reading other fields.
 285   // Competing writers must acquire exclusive access via a lock.
 286   // A losing writer waits on the lock until the winner writes f1 and leaves
 287   // the lock, so that when the losing writer returns, he can use the linked
 288   // cache entry.
 289 
 290   MonitorLockerEx ml(cpool->lock());
 291   if (!is_f1_null()) {
 292     return;
 293   }
 294 
 295   const methodHandle adapter = call_info.resolved_method();
 296   const Handle appendix      = call_info.resolved_appendix();
 297   const Handle method_type   = call_info.resolved_method_type();
 298   const bool has_appendix    = appendix.not_null();
 299   const bool has_method_type = method_type.not_null();
 300 
 301   // Write the flags.
 302   set_method_flags(as_TosState(adapter->result_type()),
 303                    ((has_appendix    ? 1 : 0) << has_appendix_shift   ) |
 304                    ((has_method_type ? 1 : 0) << has_method_type_shift) |
 305                    (                   1      << is_final_shift       ),
 306                    adapter->size_of_parameters());
 307 
 308   if (TraceInvokeDynamic) {
 309     tty->print_cr("set_method_handle bc=%d appendix="PTR_FORMAT"%s method_type="PTR_FORMAT"%s method="PTR_FORMAT" ",
 310                   invoke_code,
 311                   (void *)appendix(),    (has_appendix    ? "" : " (unused)"),
 312                   (void *)method_type(), (has_method_type ? "" : " (unused)"),
 313                   (intptr_t)adapter());
 314     adapter->print();
 315     if (has_appendix)  appendix()->print();
 316   }
 317 
 318   // Method handle invokes and invokedynamic sites use both cp cache words.
 319   // refs[f2], if not null, contains a value passed as a trailing argument to the adapter.
 320   // In the general case, this could be the call site's MethodType,
 321   // for use with java.lang.Invokers.checkExactType, or else a CallSite object.
 322   // f1 contains the adapter method which manages the actual call.
 323   // In the general case, this is a compiled LambdaForm.
 324   // (The Java code is free to optimize these calls by binding other
 325   // sorts of methods and appendices to call sites.)
 326   // JVM-level linking is via f1, as if for invokespecial, and signatures are erased.
 327   // The appendix argument (if any) is added to the signature, and is counted in the parameter_size bits.
 328   // Even with the appendix, the method will never take more than 255 parameter slots.
 329   //
 330   // This means that given a call site like (List)mh.invoke("foo"),
 331   // the f1 method has signature '(Ljl/Object;Ljl/invoke/MethodType;)Ljl/Object;',
 332   // not '(Ljava/lang/String;)Ljava/util/List;'.
 333   // The fact that String and List are involved is encoded in the MethodType in refs[f2].
 334   // This allows us to create fewer method oops, while keeping type safety.
 335   //
 336 
 337   objArrayHandle resolved_references = cpool->resolved_references();
 338   // Store appendix, if any.
 339   if (has_appendix) {
 340     const int appendix_index = f2_as_index() + _indy_resolved_references_appendix_offset;
 341     assert(appendix_index >= 0 && appendix_index < resolved_references->length(), "oob");
 342     assert(resolved_references->obj_at(appendix_index) == NULL, "init just once");
 343     resolved_references->obj_at_put(appendix_index, appendix());
 344   }
 345 
 346   // Store MethodType, if any.
 347   if (has_method_type) {
 348     const int method_type_index = f2_as_index() + _indy_resolved_references_method_type_offset;
 349     assert(method_type_index >= 0 && method_type_index < resolved_references->length(), "oob");
 350     assert(resolved_references->obj_at(method_type_index) == NULL, "init just once");
 351     resolved_references->obj_at_put(method_type_index, method_type());
 352   }
 353 
 354   release_set_f1(adapter());  // This must be the last one to set (see NOTE above)!
 355 
 356   // The interpreter assembly code does not check byte_2,
 357   // but it is used by is_resolved, method_if_resolved, etc.
 358   set_bytecode_1(invoke_code);
 359   NOT_PRODUCT(verify(tty));
 360   if (TraceInvokeDynamic) {
 361     this->print(tty, 0);
 362   }
 363 }
 364 
 365 Method* ConstantPoolCacheEntry::method_if_resolved(constantPoolHandle cpool) {
 366   // Decode the action of set_method and set_interface_call
 367   Bytecodes::Code invoke_code = bytecode_1();
 368   if (invoke_code != (Bytecodes::Code)0) {
 369     Metadata* f1 = f1_ord();
 370     if (f1 != NULL) {
 371       switch (invoke_code) {
 372       case Bytecodes::_invokeinterface:
 373         assert(f1->is_klass(), "");
 374         return klassItable::method_for_itable_index((Klass*)f1, f2_as_index());
 375       case Bytecodes::_invokestatic:
 376       case Bytecodes::_invokespecial:
 377         assert(!has_appendix(), "");
 378       case Bytecodes::_invokehandle:
 379       case Bytecodes::_invokedynamic:
 380         assert(f1->is_method(), "");
 381         return (Method*)f1;
 382       }
 383     }
 384   }
 385   invoke_code = bytecode_2();
 386   if (invoke_code != (Bytecodes::Code)0) {
 387     switch (invoke_code) {
 388     case Bytecodes::_invokevirtual:
 389       if (is_vfinal()) {
 390         // invokevirtual
 391         Method* m = f2_as_vfinal_method();
 392         assert(m->is_method(), "");
 393         return m;
 394       } else {
 395         int holder_index = cpool->uncached_klass_ref_index_at(constant_pool_index());
 396         if (cpool->tag_at(holder_index).is_klass()) {
 397           Klass* klass = cpool->resolved_klass_at(holder_index);
 398           if (!klass->oop_is_instance())
 399             klass = SystemDictionary::Object_klass();
 400           return InstanceKlass::cast(klass)->method_at_vtable(f2_as_index());
 401         }
 402       }
 403       break;
 404     }
 405   }
 406   return NULL;
 407 }
 408 
 409 
 410 oop ConstantPoolCacheEntry::appendix_if_resolved(constantPoolHandle cpool) {
 411   if (!has_appendix())
 412     return NULL;
 413   const int ref_index = f2_as_index() + _indy_resolved_references_appendix_offset;
 414   objArrayOop resolved_references = cpool->resolved_references();
 415   return resolved_references->obj_at(ref_index);
 416 }
 417 
 418 
 419 oop ConstantPoolCacheEntry::method_type_if_resolved(constantPoolHandle cpool) {
 420   if (!has_method_type())
 421     return NULL;
 422   const int ref_index = f2_as_index() + _indy_resolved_references_method_type_offset;
 423   objArrayOop resolved_references = cpool->resolved_references();
 424   return resolved_references->obj_at(ref_index);
 425 }
 426 
 427 
 428 #if INCLUDE_JVMTI
 429 // RedefineClasses() API support:
 430 // If this ConstantPoolCacheEntry refers to old_method then update it
 431 // to refer to new_method.
 432 bool ConstantPoolCacheEntry::adjust_method_entry(Method* old_method,
 433        Method* new_method, bool * trace_name_printed) {
 434 
 435   if (is_vfinal()) {
 436     // virtual and final so _f2 contains method ptr instead of vtable index
 437     if (f2_as_vfinal_method() == old_method) {
 438       // match old_method so need an update
 439       // NOTE: can't use set_f2_as_vfinal_method as it asserts on different values
 440       _f2 = (intptr_t)new_method;
 441       if (RC_TRACE_IN_RANGE(0x00100000, 0x00400000)) {
 442         if (!(*trace_name_printed)) {
 443           // RC_TRACE_MESG macro has an embedded ResourceMark
 444           RC_TRACE_MESG(("adjust: name=%s",
 445             old_method->method_holder()->external_name()));
 446           *trace_name_printed = true;
 447         }
 448         // RC_TRACE macro has an embedded ResourceMark
 449         RC_TRACE(0x00400000, ("cpc vf-entry update: %s(%s)",
 450           new_method->name()->as_C_string(),
 451           new_method->signature()->as_C_string()));
 452       }
 453 
 454       return true;
 455     }
 456 
 457     // f1() is not used with virtual entries so bail out
 458     return false;
 459   }
 460 
 461   if (_f1 == NULL) {
 462     // NULL f1() means this is a virtual entry so bail out
 463     // We are assuming that the vtable index does not need change.
 464     return false;
 465   }
 466 
 467   if (_f1 == old_method) {
 468     _f1 = new_method;
 469     if (RC_TRACE_IN_RANGE(0x00100000, 0x00400000)) {
 470       if (!(*trace_name_printed)) {
 471         // RC_TRACE_MESG macro has an embedded ResourceMark
 472         RC_TRACE_MESG(("adjust: name=%s",
 473           old_method->method_holder()->external_name()));
 474         *trace_name_printed = true;
 475       }
 476       // RC_TRACE macro has an embedded ResourceMark
 477       RC_TRACE(0x00400000, ("cpc entry update: %s(%s)",
 478         new_method->name()->as_C_string(),
 479         new_method->signature()->as_C_string()));
 480     }
 481 
 482     return true;
 483   }
 484 
 485   return false;
 486 }
 487 
 488 // a constant pool cache entry should never contain old or obsolete methods
 489 bool ConstantPoolCacheEntry::check_no_old_or_obsolete_entries() {
 490   if (is_vfinal()) {
 491     // virtual and final so _f2 contains method ptr instead of vtable index
 492     Metadata* f2 = (Metadata*)_f2;
 493     // Return false if _f2 refers to an old or an obsolete method.
 494     // _f2 == NULL || !_f2->is_method() are just as unexpected here.
 495     return (f2 != NULL NOT_PRODUCT(&& f2->is_valid()) && f2->is_method() &&
 496             !((Method*)f2)->is_old() && !((Method*)f2)->is_obsolete());
 497   } else if (_f1 == NULL ||
 498              (NOT_PRODUCT(_f1->is_valid() &&) !_f1->is_method())) {
 499     // _f1 == NULL || !_f1->is_method() are OK here
 500     return true;
 501   }
 502   // return false if _f1 refers to an old or an obsolete method
 503   return (NOT_PRODUCT(_f1->is_valid() &&) _f1->is_method() &&
 504           !((Method*)_f1)->is_old() && !((Method*)_f1)->is_obsolete());
 505 }
 506 
 507 bool ConstantPoolCacheEntry::is_interesting_method_entry(Klass* k) {
 508   if (!is_method_entry()) {
 509     // not a method entry so not interesting by default
 510     return false;
 511   }
 512 
 513   Method* m = NULL;
 514   if (is_vfinal()) {
 515     // virtual and final so _f2 contains method ptr instead of vtable index
 516     m = f2_as_vfinal_method();
 517   } else if (is_f1_null()) {
 518     // NULL _f1 means this is a virtual entry so also not interesting
 519     return false;
 520   } else {
 521     if (!(_f1->is_method())) {
 522       // _f1 can also contain a Klass* for an interface
 523       return false;
 524     }
 525     m = f1_as_method();
 526   }
 527 
 528   assert(m != NULL && m->is_method(), "sanity check");
 529   if (m == NULL || !m->is_method() || (k != NULL && m->method_holder() != k)) {
 530     // robustness for above sanity checks or method is not in
 531     // the interesting class
 532     return false;
 533   }
 534 
 535   // the method is in the interesting class so the entry is interesting
 536   return true;
 537 }
 538 #endif // INCLUDE_JVMTI
 539 
 540 void ConstantPoolCacheEntry::print(outputStream* st, int index) const {
 541   // print separator
 542   if (index == 0) st->print_cr("                 -------------");
 543   // print entry
 544   st->print("%3d  ("PTR_FORMAT")  ", index, (intptr_t)this);
 545   st->print_cr("[%02x|%02x|%5d]", bytecode_2(), bytecode_1(),
 546                constant_pool_index());
 547   st->print_cr("                 [   "PTR_FORMAT"]", (intptr_t)_f1);
 548   st->print_cr("                 [   "PTR_FORMAT"]", (intptr_t)_f2);
 549   st->print_cr("                 [   "PTR_FORMAT"]", (intptr_t)_flags);
 550   st->print_cr("                 -------------");
 551 }
 552 
 553 void ConstantPoolCacheEntry::verify(outputStream* st) const {
 554   // not implemented yet
 555 }
 556 
 557 // Implementation of ConstantPoolCache
 558 
 559 ConstantPoolCache* ConstantPoolCache::allocate(ClassLoaderData* loader_data,
 560                                      const intStack& index_map,
 561                                      const intStack& invokedynamic_index_map,
 562                                      const intStack& invokedynamic_map, TRAPS) {
 563 
 564   const int length = index_map.length() + invokedynamic_index_map.length();
 565   int size = ConstantPoolCache::size(length);
 566 
 567   return new (loader_data, size, false, MetaspaceObj::ConstantPoolCacheType, THREAD)
 568     ConstantPoolCache(length, index_map, invokedynamic_index_map, invokedynamic_map);
 569 }
 570 
 571 void ConstantPoolCache::initialize(const intArray& inverse_index_map,
 572                                    const intArray& invokedynamic_inverse_index_map,
 573                                    const intArray& invokedynamic_references_map) {
 574   for (int i = 0; i < inverse_index_map.length(); i++) {
 575     ConstantPoolCacheEntry* e = entry_at(i);
 576     int original_index = inverse_index_map[i];
 577     e->initialize_entry(original_index);
 578     assert(entry_at(i) == e, "sanity");
 579   }
 580 
 581   // Append invokedynamic entries at the end
 582   int invokedynamic_offset = inverse_index_map.length();
 583   for (int i = 0; i < invokedynamic_inverse_index_map.length(); i++) {
 584     int offset = i + invokedynamic_offset;
 585     ConstantPoolCacheEntry* e = entry_at(offset);
 586     int original_index = invokedynamic_inverse_index_map[i];
 587     e->initialize_entry(original_index);
 588     assert(entry_at(offset) == e, "sanity");
 589   }
 590 
 591   for (int ref = 0; ref < invokedynamic_references_map.length(); ref++) {
 592     const int cpci = invokedynamic_references_map[ref];
 593     if (cpci >= 0) {
 594 #ifdef ASSERT
 595       // invokedynamic and invokehandle have more entries; check if they
 596       // all point to the same constant pool cache entry.
 597       for (int entry = 1; entry < ConstantPoolCacheEntry::_indy_resolved_references_entries; entry++) {
 598         const int cpci_next = invokedynamic_references_map[ref + entry];
 599         assert(cpci == cpci_next, err_msg_res("%d == %d", cpci, cpci_next));
 600       }
 601 #endif
 602       entry_at(cpci)->initialize_resolved_reference_index(ref);
 603       ref += ConstantPoolCacheEntry::_indy_resolved_references_entries - 1;  // skip extra entries
 604     }
 605   }
 606 }
 607 
 608 #if INCLUDE_JVMTI
 609 // RedefineClasses() API support:
 610 // If any entry of this ConstantPoolCache points to any of
 611 // old_methods, replace it with the corresponding new_method.
 612 void ConstantPoolCache::adjust_method_entries(Method** old_methods, Method** new_methods,
 613                                                      int methods_length, bool * trace_name_printed) {
 614 
 615   if (methods_length == 0) {
 616     // nothing to do if there are no methods
 617     return;
 618   }
 619 
 620   // get shorthand for the interesting class
 621   Klass* old_holder = old_methods[0]->method_holder();
 622 
 623   for (int i = 0; i < length(); i++) {
 624     if (!entry_at(i)->is_interesting_method_entry(old_holder)) {
 625       // skip uninteresting methods
 626       continue;
 627     }
 628 
 629     // The ConstantPoolCache contains entries for several different
 630     // things, but we only care about methods. In fact, we only care
 631     // about methods in the same class as the one that contains the
 632     // old_methods. At this point, we have an interesting entry.
 633 
 634     for (int j = 0; j < methods_length; j++) {
 635       Method* old_method = old_methods[j];
 636       Method* new_method = new_methods[j];
 637 
 638       if (entry_at(i)->adjust_method_entry(old_method, new_method,
 639           trace_name_printed)) {
 640         // current old_method matched this entry and we updated it so
 641         // break out and get to the next interesting entry if there one
 642         break;
 643       }
 644     }
 645   }
 646 }
 647 
 648 // the constant pool cache should never contain old or obsolete methods
 649 bool ConstantPoolCache::check_no_old_or_obsolete_entries() {
 650   for (int i = 1; i < length(); i++) {
 651     if (entry_at(i)->is_interesting_method_entry(NULL) &&
 652         !entry_at(i)->check_no_old_or_obsolete_entries()) {
 653       return false;
 654     }
 655   }
 656   return true;
 657 }
 658 
 659 void ConstantPoolCache::dump_cache() {
 660   for (int i = 1; i < length(); i++) {
 661     if (entry_at(i)->is_interesting_method_entry(NULL)) {
 662       entry_at(i)->print(tty, i);
 663     }
 664   }
 665 }
 666 #endif // INCLUDE_JVMTI
 667 
 668 
 669 // Printing
 670 
 671 void ConstantPoolCache::print_on(outputStream* st) const {
 672   assert(is_constantPoolCache(), "obj must be constant pool cache");
 673   st->print_cr("%s", internal_name());
 674   // print constant pool cache entries
 675   for (int i = 0; i < length(); i++) entry_at(i)->print(st, i);
 676 }
 677 
 678 void ConstantPoolCache::print_value_on(outputStream* st) const {
 679   assert(is_constantPoolCache(), "obj must be constant pool cache");
 680   st->print("cache [%d]", length());
 681   print_address_on(st);
 682   st->print(" for ");
 683   constant_pool()->print_value_on(st);
 684 }
 685 
 686 
 687 // Verification
 688 
 689 void ConstantPoolCache::verify_on(outputStream* st) {
 690   guarantee(is_constantPoolCache(), "obj must be constant pool cache");
 691   // print constant pool cache entries
 692   for (int i = 0; i < length(); i++) entry_at(i)->verify(st);
 693 }