1 /*
   2  * Copyright (c) 1997, 2016, 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 "classfile/classLoaderData.hpp"
  27 #include "classfile/javaClasses.inline.hpp"
  28 #include "classfile/metadataOnStackMark.hpp"
  29 #include "classfile/stringTable.hpp"
  30 #include "classfile/systemDictionary.hpp"
  31 #include "classfile/vmSymbols.hpp"
  32 #include "interpreter/linkResolver.hpp"
  33 #include "memory/heapInspection.hpp"
  34 #include "memory/metadataFactory.hpp"
  35 #include "memory/oopFactory.hpp"
  36 #include "memory/resourceArea.hpp"
  37 #include "oops/constantPool.hpp"
  38 #include "oops/instanceKlass.hpp"
  39 #include "oops/objArrayKlass.hpp"
  40 #include "oops/objArrayOop.inline.hpp"
  41 #include "oops/oop.inline.hpp"
  42 #include "runtime/fieldType.hpp"
  43 #include "runtime/init.hpp"
  44 #include "runtime/javaCalls.hpp"
  45 #include "runtime/signature.hpp"
  46 #include "runtime/vframe.hpp"
  47 #include "utilities/copy.hpp"
  48 
  49 ConstantPool* ConstantPool::allocate(ClassLoaderData* loader_data, int length, TRAPS) {
  50   // Tags are RW but comment below applies to tags also.
  51   Array<u1>* tags = MetadataFactory::new_writeable_array<u1>(loader_data, length, 0, CHECK_NULL);
  52 
  53   int size = ConstantPool::size(length);
  54 
  55   // CDS considerations:
  56   // Allocate read-write but may be able to move to read-only at dumping time
  57   // if all the klasses are resolved.  The only other field that is writable is
  58   // the resolved_references array, which is recreated at startup time.
  59   // But that could be moved to InstanceKlass (although a pain to access from
  60   // assembly code).  Maybe it could be moved to the cpCache which is RW.
  61   return new (loader_data, size, false, MetaspaceObj::ConstantPoolType, THREAD) ConstantPool(tags);
  62 }
  63 
  64 #ifdef ASSERT
  65 
  66 // MetaspaceObj allocation invariant is calloc equivalent memory
  67 // simple verification of this here (JVM_CONSTANT_Invalid == 0 )
  68 static bool tag_array_is_zero_initialized(Array<u1>* tags) {
  69   assert(tags != NULL, "invariant");
  70   const int length = tags->length();
  71   for (int index = 0; index < length; ++index) {
  72     if (JVM_CONSTANT_Invalid != tags->at(index)) {
  73       return false;
  74     }
  75   }
  76   return true;
  77 }
  78 
  79 #endif
  80 
  81 ConstantPool::ConstantPool(Array<u1>* tags) :
  82   _tags(tags),
  83   _length(tags->length()) {
  84 
  85     assert(_tags != NULL, "invariant");
  86     assert(tags->length() == _length, "invariant");
  87     assert(tag_array_is_zero_initialized(tags), "invariant");
  88     assert(0 == _flags, "invariant");
  89     assert(0 == version(), "invariant");
  90     assert(NULL == _pool_holder, "invariant");
  91 }
  92 
  93 void ConstantPool::deallocate_contents(ClassLoaderData* loader_data) {
  94   MetadataFactory::free_metadata(loader_data, cache());
  95   set_cache(NULL);
  96   MetadataFactory::free_array<u2>(loader_data, reference_map());
  97   set_reference_map(NULL);
  98 
  99   MetadataFactory::free_array<jushort>(loader_data, operands());
 100   set_operands(NULL);
 101 
 102   release_C_heap_structures();
 103 
 104   // free tag array
 105   MetadataFactory::free_array<u1>(loader_data, tags());
 106   set_tags(NULL);
 107 }
 108 
 109 void ConstantPool::release_C_heap_structures() {
 110   // walk constant pool and decrement symbol reference counts
 111   unreference_symbols();
 112 }
 113 
 114 objArrayOop ConstantPool::resolved_references() const {
 115   return (objArrayOop)JNIHandles::resolve(_resolved_references);
 116 }
 117 
 118 // Create resolved_references array and mapping array for original cp indexes
 119 // The ldc bytecode was rewritten to have the resolved reference array index so need a way
 120 // to map it back for resolving and some unlikely miscellaneous uses.
 121 // The objects created by invokedynamic are appended to this list.
 122 void ConstantPool::initialize_resolved_references(ClassLoaderData* loader_data,
 123                                                   const intStack& reference_map,
 124                                                   int constant_pool_map_length,
 125                                                   TRAPS) {
 126   // Initialized the resolved object cache.
 127   int map_length = reference_map.length();
 128   if (map_length > 0) {
 129     // Only need mapping back to constant pool entries.  The map isn't used for
 130     // invokedynamic resolved_reference entries.  For invokedynamic entries,
 131     // the constant pool cache index has the mapping back to both the constant
 132     // pool and to the resolved reference index.
 133     if (constant_pool_map_length > 0) {
 134       Array<u2>* om = MetadataFactory::new_array<u2>(loader_data, constant_pool_map_length, CHECK);
 135 
 136       for (int i = 0; i < constant_pool_map_length; i++) {
 137         int x = reference_map.at(i);
 138         assert(x == (int)(jushort) x, "klass index is too big");
 139         om->at_put(i, (jushort)x);
 140       }
 141       set_reference_map(om);
 142     }
 143 
 144     // Create Java array for holding resolved strings, methodHandles,
 145     // methodTypes, invokedynamic and invokehandle appendix objects, etc.
 146     objArrayOop stom = oopFactory::new_objArray(SystemDictionary::Object_klass(), map_length, CHECK);
 147     Handle refs_handle (THREAD, (oop)stom);  // must handleize.
 148     set_resolved_references(loader_data->add_handle(refs_handle));
 149   }
 150 }
 151 
 152 // CDS support. Create a new resolved_references array.
 153 void ConstantPool::restore_unshareable_info(TRAPS) {
 154 
 155   // Only create the new resolved references array if it hasn't been attempted before
 156   if (resolved_references() != NULL) return;
 157 
 158   // restore the C++ vtable from the shared archive
 159   restore_vtable();
 160 
 161   if (SystemDictionary::Object_klass_loaded()) {
 162     // Recreate the object array and add to ClassLoaderData.
 163     int map_length = resolved_reference_length();
 164     if (map_length > 0) {
 165       objArrayOop stom = oopFactory::new_objArray(SystemDictionary::Object_klass(), map_length, CHECK);
 166       Handle refs_handle (THREAD, (oop)stom);  // must handleize.
 167 
 168       ClassLoaderData* loader_data = pool_holder()->class_loader_data();
 169       set_resolved_references(loader_data->add_handle(refs_handle));
 170     }
 171   }
 172 }
 173 
 174 void ConstantPool::remove_unshareable_info() {
 175   // Resolved references are not in the shared archive.
 176   // Save the length for restoration.  It is not necessarily the same length
 177   // as reference_map.length() if invokedynamic is saved.
 178   set_resolved_reference_length(
 179     resolved_references() != NULL ? resolved_references()->length() : 0);
 180   set_resolved_references(NULL);
 181 }
 182 
 183 int ConstantPool::cp_to_object_index(int cp_index) {
 184   // this is harder don't do this so much.
 185   int i = reference_map()->find(cp_index);
 186   // We might not find the index for jsr292 call.
 187   return (i < 0) ? _no_index_sentinel : i;
 188 }
 189 
 190 void ConstantPool::string_at_put(int which, int obj_index, oop str) {
 191   resolved_references()->obj_at_put(obj_index, str);
 192 }
 193 
 194 void ConstantPool::trace_class_resolution(const constantPoolHandle& this_cp, KlassHandle k) {
 195   ResourceMark rm;
 196   int line_number = -1;
 197   const char * source_file = NULL;
 198   if (JavaThread::current()->has_last_Java_frame()) {
 199     // try to identify the method which called this function.
 200     vframeStream vfst(JavaThread::current());
 201     if (!vfst.at_end()) {
 202       line_number = vfst.method()->line_number_from_bci(vfst.bci());
 203       Symbol* s = vfst.method()->method_holder()->source_file_name();
 204       if (s != NULL) {
 205         source_file = s->as_C_string();
 206       }
 207     }
 208   }
 209   if (k() != this_cp->pool_holder()) {
 210     // only print something if the classes are different
 211     if (source_file != NULL) {
 212       log_debug(classresolve)("%s %s %s:%d",
 213                  this_cp->pool_holder()->external_name(),
 214                  k->external_name(), source_file, line_number);
 215     } else {
 216       log_debug(classresolve)("%s %s",
 217                  this_cp->pool_holder()->external_name(),
 218                  k->external_name());
 219     }
 220   }
 221 }
 222 
 223 Klass* ConstantPool::klass_at_impl(const constantPoolHandle& this_cp, int which,
 224                                    bool save_resolution_error, TRAPS) {
 225   assert(THREAD->is_Java_thread(), "must be a Java thread");
 226 
 227   // A resolved constantPool entry will contain a Klass*, otherwise a Symbol*.
 228   // It is not safe to rely on the tag bit's here, since we don't have a lock, and
 229   // the entry and tag is not updated atomicly.
 230   CPSlot entry = this_cp->slot_at(which);
 231   if (entry.is_resolved()) {
 232     assert(entry.get_klass()->is_klass(), "must be");
 233     // Already resolved - return entry.
 234     return entry.get_klass();
 235   }
 236 
 237   // This tag doesn't change back to unresolved class unless at a safepoint.
 238   if (this_cp->tag_at(which).is_unresolved_klass_in_error()) {
 239     // The original attempt to resolve this constant pool entry failed so find the
 240     // class of the original error and throw another error of the same class
 241     // (JVMS 5.4.3).
 242     // If there is a detail message, pass that detail message to the error.
 243     // The JVMS does not strictly require us to duplicate the same detail message,
 244     // or any internal exception fields such as cause or stacktrace.  But since the
 245     // detail message is often a class name or other literal string, we will repeat it
 246     // if we can find it in the symbol table.
 247     throw_resolution_error(this_cp, which, CHECK_0);
 248     ShouldNotReachHere();
 249   }
 250 
 251   Handle mirror_handle;
 252   Symbol* name = entry.get_symbol();
 253   Handle loader (THREAD, this_cp->pool_holder()->class_loader());
 254   Handle protection_domain (THREAD, this_cp->pool_holder()->protection_domain());
 255   Klass* kk = SystemDictionary::resolve_or_fail(name, loader, protection_domain, true, THREAD);
 256   KlassHandle k (THREAD, kk);
 257   if (!HAS_PENDING_EXCEPTION) {
 258     // preserve the resolved klass from unloading
 259     mirror_handle = Handle(THREAD, kk->java_mirror());
 260     // Do access check for klasses
 261     verify_constant_pool_resolve(this_cp, k, THREAD);
 262   }
 263 
 264   // Failed to resolve class. We must record the errors so that subsequent attempts
 265   // to resolve this constant pool entry fail with the same error (JVMS 5.4.3).
 266   if (HAS_PENDING_EXCEPTION) {
 267     if (save_resolution_error) {
 268       save_and_throw_exception(this_cp, which, constantTag(JVM_CONSTANT_UnresolvedClass), CHECK_NULL);
 269       // If CHECK_NULL above doesn't return the exception, that means that
 270       // some other thread has beaten us and has resolved the class.
 271       // To preserve old behavior, we return the resolved class.
 272       entry = this_cp->resolved_klass_at(which);
 273       assert(entry.is_resolved(), "must be resolved if exception was cleared");
 274       assert(entry.get_klass()->is_klass(), "must be resolved to a klass");
 275       return entry.get_klass();
 276     } else {
 277       return NULL;  // return the pending exception
 278     }
 279   }
 280 
 281   // Make this class loader depend upon the class loader owning the class reference
 282   ClassLoaderData* this_key = this_cp->pool_holder()->class_loader_data();
 283   this_key->record_dependency(k(), CHECK_NULL); // Can throw OOM
 284 
 285   // logging for classresolve tag.
 286   trace_class_resolution(this_cp, k);
 287 
 288   this_cp->klass_at_put(which, k());
 289   entry = this_cp->resolved_klass_at(which);
 290   assert(entry.is_resolved() && entry.get_klass()->is_klass(), "must be resolved at this point");
 291   return entry.get_klass();
 292 }
 293 
 294 
 295 // Does not update ConstantPool* - to avoid any exception throwing. Used
 296 // by compiler and exception handling.  Also used to avoid classloads for
 297 // instanceof operations. Returns NULL if the class has not been loaded or
 298 // if the verification of constant pool failed
 299 Klass* ConstantPool::klass_at_if_loaded(const constantPoolHandle& this_cp, int which) {
 300   CPSlot entry = this_cp->slot_at(which);
 301   if (entry.is_resolved()) {
 302     assert(entry.get_klass()->is_klass(), "must be");
 303     return entry.get_klass();
 304   } else {
 305     assert(entry.is_unresolved(), "must be either symbol or klass");
 306     Thread *thread = Thread::current();
 307     Symbol* name = entry.get_symbol();
 308     oop loader = this_cp->pool_holder()->class_loader();
 309     oop protection_domain = this_cp->pool_holder()->protection_domain();
 310     Handle h_prot (thread, protection_domain);
 311     Handle h_loader (thread, loader);
 312     Klass* k = SystemDictionary::find(name, h_loader, h_prot, thread);
 313 
 314     if (k != NULL) {
 315       // Make sure that resolving is legal
 316       EXCEPTION_MARK;
 317       KlassHandle klass(THREAD, k);
 318       // return NULL if verification fails
 319       verify_constant_pool_resolve(this_cp, klass, THREAD);
 320       if (HAS_PENDING_EXCEPTION) {
 321         CLEAR_PENDING_EXCEPTION;
 322         return NULL;
 323       }
 324       return klass();
 325     } else {
 326       return k;
 327     }
 328   }
 329 }
 330 
 331 
 332 Klass* ConstantPool::klass_ref_at_if_loaded(const constantPoolHandle& this_cp, int which) {
 333   return klass_at_if_loaded(this_cp, this_cp->klass_ref_index_at(which));
 334 }
 335 
 336 
 337 Method* ConstantPool::method_at_if_loaded(const constantPoolHandle& cpool,
 338                                                    int which) {
 339   if (cpool->cache() == NULL)  return NULL;  // nothing to load yet
 340   int cache_index = decode_cpcache_index(which, true);
 341   if (!(cache_index >= 0 && cache_index < cpool->cache()->length())) {
 342     // FIXME: should be an assert
 343     if (PrintMiscellaneous && (Verbose||WizardMode)) {
 344       tty->print_cr("bad operand %d in:", which); cpool->print();
 345     }
 346     return NULL;
 347   }
 348   ConstantPoolCacheEntry* e = cpool->cache()->entry_at(cache_index);
 349   return e->method_if_resolved(cpool);
 350 }
 351 
 352 
 353 bool ConstantPool::has_appendix_at_if_loaded(const constantPoolHandle& cpool, int which) {
 354   if (cpool->cache() == NULL)  return false;  // nothing to load yet
 355   int cache_index = decode_cpcache_index(which, true);
 356   ConstantPoolCacheEntry* e = cpool->cache()->entry_at(cache_index);
 357   return e->has_appendix();
 358 }
 359 
 360 oop ConstantPool::appendix_at_if_loaded(const constantPoolHandle& cpool, int which) {
 361   if (cpool->cache() == NULL)  return NULL;  // nothing to load yet
 362   int cache_index = decode_cpcache_index(which, true);
 363   ConstantPoolCacheEntry* e = cpool->cache()->entry_at(cache_index);
 364   return e->appendix_if_resolved(cpool);
 365 }
 366 
 367 
 368 bool ConstantPool::has_method_type_at_if_loaded(const constantPoolHandle& cpool, int which) {
 369   if (cpool->cache() == NULL)  return false;  // nothing to load yet
 370   int cache_index = decode_cpcache_index(which, true);
 371   ConstantPoolCacheEntry* e = cpool->cache()->entry_at(cache_index);
 372   return e->has_method_type();
 373 }
 374 
 375 oop ConstantPool::method_type_at_if_loaded(const constantPoolHandle& cpool, int which) {
 376   if (cpool->cache() == NULL)  return NULL;  // nothing to load yet
 377   int cache_index = decode_cpcache_index(which, true);
 378   ConstantPoolCacheEntry* e = cpool->cache()->entry_at(cache_index);
 379   return e->method_type_if_resolved(cpool);
 380 }
 381 
 382 
 383 Symbol* ConstantPool::impl_name_ref_at(int which, bool uncached) {
 384   int name_index = name_ref_index_at(impl_name_and_type_ref_index_at(which, uncached));
 385   return symbol_at(name_index);
 386 }
 387 
 388 
 389 Symbol* ConstantPool::impl_signature_ref_at(int which, bool uncached) {
 390   int signature_index = signature_ref_index_at(impl_name_and_type_ref_index_at(which, uncached));
 391   return symbol_at(signature_index);
 392 }
 393 
 394 
 395 int ConstantPool::impl_name_and_type_ref_index_at(int which, bool uncached) {
 396   int i = which;
 397   if (!uncached && cache() != NULL) {
 398     if (ConstantPool::is_invokedynamic_index(which)) {
 399       // Invokedynamic index is index into resolved_references
 400       int pool_index = invokedynamic_cp_cache_entry_at(which)->constant_pool_index();
 401       pool_index = invoke_dynamic_name_and_type_ref_index_at(pool_index);
 402       assert(tag_at(pool_index).is_name_and_type(), "");
 403       return pool_index;
 404     }
 405     // change byte-ordering and go via cache
 406     i = remap_instruction_operand_from_cache(which);
 407   } else {
 408     if (tag_at(which).is_invoke_dynamic()) {
 409       int pool_index = invoke_dynamic_name_and_type_ref_index_at(which);
 410       assert(tag_at(pool_index).is_name_and_type(), "");
 411       return pool_index;
 412     }
 413   }
 414   assert(tag_at(i).is_field_or_method(), "Corrupted constant pool");
 415   assert(!tag_at(i).is_invoke_dynamic(), "Must be handled above");
 416   jint ref_index = *int_at_addr(i);
 417   return extract_high_short_from_int(ref_index);
 418 }
 419 
 420 
 421 int ConstantPool::impl_klass_ref_index_at(int which, bool uncached) {
 422   guarantee(!ConstantPool::is_invokedynamic_index(which),
 423             "an invokedynamic instruction does not have a klass");
 424   int i = which;
 425   if (!uncached && cache() != NULL) {
 426     // change byte-ordering and go via cache
 427     i = remap_instruction_operand_from_cache(which);
 428   }
 429   assert(tag_at(i).is_field_or_method(), "Corrupted constant pool");
 430   jint ref_index = *int_at_addr(i);
 431   return extract_low_short_from_int(ref_index);
 432 }
 433 
 434 
 435 
 436 int ConstantPool::remap_instruction_operand_from_cache(int operand) {
 437   int cpc_index = operand;
 438   DEBUG_ONLY(cpc_index -= CPCACHE_INDEX_TAG);
 439   assert((int)(u2)cpc_index == cpc_index, "clean u2");
 440   int member_index = cache()->entry_at(cpc_index)->constant_pool_index();
 441   return member_index;
 442 }
 443 
 444 
 445 void ConstantPool::verify_constant_pool_resolve(const constantPoolHandle& this_cp, KlassHandle k, TRAPS) {
 446  if (k->is_instance_klass() || k->is_objArray_klass()) {
 447     instanceKlassHandle holder (THREAD, this_cp->pool_holder());
 448     Klass* elem = k->is_instance_klass() ? k() : ObjArrayKlass::cast(k())->bottom_klass();
 449     KlassHandle element (THREAD, elem);
 450 
 451     // The element type could be a typeArray - we only need the access check if it is
 452     // an reference to another class
 453     if (element->is_instance_klass()) {
 454       LinkResolver::check_klass_accessability(holder, element, CHECK);
 455     }
 456   }
 457 }
 458 
 459 
 460 int ConstantPool::name_ref_index_at(int which_nt) {
 461   jint ref_index = name_and_type_at(which_nt);
 462   return extract_low_short_from_int(ref_index);
 463 }
 464 
 465 
 466 int ConstantPool::signature_ref_index_at(int which_nt) {
 467   jint ref_index = name_and_type_at(which_nt);
 468   return extract_high_short_from_int(ref_index);
 469 }
 470 
 471 
 472 Klass* ConstantPool::klass_ref_at(int which, TRAPS) {
 473   return klass_at(klass_ref_index_at(which), THREAD);
 474 }
 475 
 476 
 477 Symbol* ConstantPool::klass_name_at(int which) const {
 478   assert(tag_at(which).is_unresolved_klass() || tag_at(which).is_klass(),
 479          "Corrupted constant pool");
 480   // A resolved constantPool entry will contain a Klass*, otherwise a Symbol*.
 481   // It is not safe to rely on the tag bit's here, since we don't have a lock, and the entry and
 482   // tag is not updated atomicly.
 483   CPSlot entry = slot_at(which);
 484   if (entry.is_resolved()) {
 485     // Already resolved - return entry's name.
 486     assert(entry.get_klass()->is_klass(), "must be");
 487     return entry.get_klass()->name();
 488   } else {
 489     assert(entry.is_unresolved(), "must be either symbol or klass");
 490     return entry.get_symbol();
 491   }
 492 }
 493 
 494 Symbol* ConstantPool::klass_ref_at_noresolve(int which) {
 495   jint ref_index = klass_ref_index_at(which);
 496   return klass_at_noresolve(ref_index);
 497 }
 498 
 499 Symbol* ConstantPool::uncached_klass_ref_at_noresolve(int which) {
 500   jint ref_index = uncached_klass_ref_index_at(which);
 501   return klass_at_noresolve(ref_index);
 502 }
 503 
 504 char* ConstantPool::string_at_noresolve(int which) {
 505   return unresolved_string_at(which)->as_C_string();
 506 }
 507 
 508 BasicType ConstantPool::basic_type_for_signature_at(int which) const {
 509   return FieldType::basic_type(symbol_at(which));
 510 }
 511 
 512 
 513 void ConstantPool::resolve_string_constants_impl(const constantPoolHandle& this_cp, TRAPS) {
 514   for (int index = 1; index < this_cp->length(); index++) { // Index 0 is unused
 515     if (this_cp->tag_at(index).is_string()) {
 516       this_cp->string_at(index, CHECK);
 517     }
 518   }
 519 }
 520 
 521 // Resolve all the classes in the constant pool.  If they are all resolved,
 522 // the constant pool is read-only.  Enhancement: allocate cp entries to
 523 // another metaspace, and copy to read-only or read-write space if this
 524 // bit is set.
 525 bool ConstantPool::resolve_class_constants(TRAPS) {
 526   constantPoolHandle cp(THREAD, this);
 527   for (int index = 1; index < length(); index++) { // Index 0 is unused
 528     if (tag_at(index).is_unresolved_klass() &&
 529         klass_at_if_loaded(cp, index) == NULL) {
 530       return false;
 531   }
 532   }
 533   // set_preresolution(); or some bit for future use
 534   return true;
 535 }
 536 
 537 Symbol* ConstantPool::exception_message(const constantPoolHandle& this_cp, int which, constantTag tag, oop pending_exception) {
 538   // Dig out the detailed message to reuse if possible
 539   Symbol* message = java_lang_Throwable::detail_message(pending_exception);
 540   if (message != NULL) {
 541     return message;
 542   }
 543 
 544   // Return specific message for the tag
 545   switch (tag.value()) {
 546   case JVM_CONSTANT_UnresolvedClass:
 547     // return the class name in the error message
 548     message = this_cp->klass_name_at(which);
 549     break;
 550   case JVM_CONSTANT_MethodHandle:
 551     // return the method handle name in the error message
 552     message = this_cp->method_handle_name_ref_at(which);
 553     break;
 554   case JVM_CONSTANT_MethodType:
 555     // return the method type signature in the error message
 556     message = this_cp->method_type_signature_at(which);
 557     break;
 558   default:
 559     ShouldNotReachHere();
 560   }
 561 
 562   return message;
 563 }
 564 
 565 void ConstantPool::throw_resolution_error(const constantPoolHandle& this_cp, int which, TRAPS) {
 566   Symbol* message = NULL;
 567   Symbol* error = SystemDictionary::find_resolution_error(this_cp, which, &message);
 568   assert(error != NULL && message != NULL, "checking");
 569   CLEAR_PENDING_EXCEPTION;
 570   ResourceMark rm;
 571   THROW_MSG(error, message->as_C_string());
 572 }
 573 
 574 // If resolution for Class, MethodHandle or MethodType fails, save the exception
 575 // in the resolution error table, so that the same exception is thrown again.
 576 void ConstantPool::save_and_throw_exception(const constantPoolHandle& this_cp, int which,
 577                                             constantTag tag, TRAPS) {
 578   Symbol* error = PENDING_EXCEPTION->klass()->name();
 579 
 580   int error_tag = tag.error_value();
 581 
 582   if (!PENDING_EXCEPTION->
 583     is_a(SystemDictionary::LinkageError_klass())) {
 584     // Just throw the exception and don't prevent these classes from
 585     // being loaded due to virtual machine errors like StackOverflow
 586     // and OutOfMemoryError, etc, or if the thread was hit by stop()
 587     // Needs clarification to section 5.4.3 of the VM spec (see 6308271)
 588   } else if (this_cp->tag_at(which).value() != error_tag) {
 589     Symbol* message = exception_message(this_cp, which, tag, PENDING_EXCEPTION);
 590     SystemDictionary::add_resolution_error(this_cp, which, error, message);
 591     // CAS in the tag.  If a thread beat us to registering this error that's fine.
 592     // If another thread resolved the reference, this is a race condition. This
 593     // thread may have had a security manager or something temporary.
 594     // This doesn't deterministically get an error.   So why do we save this?
 595     // We save this because jvmti can add classes to the bootclass path after
 596     // this error, so it needs to get the same error if the error is first.
 597     jbyte old_tag = Atomic::cmpxchg((jbyte)error_tag,
 598                             (jbyte*)this_cp->tag_addr_at(which), (jbyte)tag.value());
 599     if (old_tag != error_tag && old_tag != tag.value()) {
 600       // MethodHandles and MethodType doesn't change to resolved version.
 601       assert(this_cp->tag_at(which).is_klass(), "Wrong tag value");
 602       // Forget the exception and use the resolved class.
 603       CLEAR_PENDING_EXCEPTION;
 604     }
 605   } else {
 606     // some other thread put this in error state
 607     throw_resolution_error(this_cp, which, CHECK);
 608   }
 609 }
 610 
 611 // Called to resolve constants in the constant pool and return an oop.
 612 // Some constant pool entries cache their resolved oop. This is also
 613 // called to create oops from constants to use in arguments for invokedynamic
 614 oop ConstantPool::resolve_constant_at_impl(const constantPoolHandle& this_cp, int index, int cache_index, TRAPS) {
 615   oop result_oop = NULL;
 616   Handle throw_exception;
 617 
 618   if (cache_index == _possible_index_sentinel) {
 619     // It is possible that this constant is one which is cached in the objects.
 620     // We'll do a linear search.  This should be OK because this usage is rare.
 621     assert(index > 0, "valid index");
 622     cache_index = this_cp->cp_to_object_index(index);
 623   }
 624   assert(cache_index == _no_index_sentinel || cache_index >= 0, "");
 625   assert(index == _no_index_sentinel || index >= 0, "");
 626 
 627   if (cache_index >= 0) {
 628     result_oop = this_cp->resolved_references()->obj_at(cache_index);
 629     if (result_oop != NULL) {
 630       return result_oop;
 631       // That was easy...
 632     }
 633     index = this_cp->object_to_cp_index(cache_index);
 634   }
 635 
 636   jvalue prim_value;  // temp used only in a few cases below
 637 
 638   constantTag tag = this_cp->tag_at(index);
 639 
 640   switch (tag.value()) {
 641 
 642   case JVM_CONSTANT_UnresolvedClass:
 643   case JVM_CONSTANT_UnresolvedClassInError:
 644   case JVM_CONSTANT_Class:
 645     {
 646       assert(cache_index == _no_index_sentinel, "should not have been set");
 647       Klass* resolved = klass_at_impl(this_cp, index, true, CHECK_NULL);
 648       // ldc wants the java mirror.
 649       result_oop = resolved->java_mirror();
 650       break;
 651     }
 652 
 653   case JVM_CONSTANT_String:
 654     assert(cache_index != _no_index_sentinel, "should have been set");
 655     if (this_cp->is_pseudo_string_at(index)) {
 656       result_oop = this_cp->pseudo_string_at(index, cache_index);
 657       break;
 658     }
 659     result_oop = string_at_impl(this_cp, index, cache_index, CHECK_NULL);
 660     break;
 661 
 662   case JVM_CONSTANT_MethodHandleInError:
 663   case JVM_CONSTANT_MethodTypeInError:
 664     {
 665       throw_resolution_error(this_cp, index, CHECK_NULL);
 666       break;
 667     }
 668 
 669   case JVM_CONSTANT_MethodHandle:
 670     {
 671       int ref_kind                 = this_cp->method_handle_ref_kind_at(index);
 672       int callee_index             = this_cp->method_handle_klass_index_at(index);
 673       Symbol*  name =      this_cp->method_handle_name_ref_at(index);
 674       Symbol*  signature = this_cp->method_handle_signature_ref_at(index);
 675       if (PrintMiscellaneous)
 676         tty->print_cr("resolve JVM_CONSTANT_MethodHandle:%d [%d/%d/%d] %s.%s",
 677                       ref_kind, index, this_cp->method_handle_index_at(index),
 678                       callee_index, name->as_C_string(), signature->as_C_string());
 679       KlassHandle callee;
 680       { Klass* k = klass_at_impl(this_cp, callee_index, true, CHECK_NULL);
 681         callee = KlassHandle(THREAD, k);
 682       }
 683       KlassHandle klass(THREAD, this_cp->pool_holder());
 684       Handle value = SystemDictionary::link_method_handle_constant(klass, ref_kind,
 685                                                                    callee, name, signature,
 686                                                                    THREAD);
 687       result_oop = value();
 688       if (HAS_PENDING_EXCEPTION) {
 689         save_and_throw_exception(this_cp, index, tag, CHECK_NULL);
 690       }
 691       break;
 692     }
 693 
 694   case JVM_CONSTANT_MethodType:
 695     {
 696       Symbol*  signature = this_cp->method_type_signature_at(index);
 697       if (PrintMiscellaneous)
 698         tty->print_cr("resolve JVM_CONSTANT_MethodType [%d/%d] %s",
 699                       index, this_cp->method_type_index_at(index),
 700                       signature->as_C_string());
 701       KlassHandle klass(THREAD, this_cp->pool_holder());
 702       Handle value = SystemDictionary::find_method_handle_type(signature, klass, THREAD);
 703       result_oop = value();
 704       if (HAS_PENDING_EXCEPTION) {
 705         save_and_throw_exception(this_cp, index, tag, CHECK_NULL);
 706       }
 707       break;
 708     }
 709 
 710   case JVM_CONSTANT_Integer:
 711     assert(cache_index == _no_index_sentinel, "should not have been set");
 712     prim_value.i = this_cp->int_at(index);
 713     result_oop = java_lang_boxing_object::create(T_INT, &prim_value, CHECK_NULL);
 714     break;
 715 
 716   case JVM_CONSTANT_Float:
 717     assert(cache_index == _no_index_sentinel, "should not have been set");
 718     prim_value.f = this_cp->float_at(index);
 719     result_oop = java_lang_boxing_object::create(T_FLOAT, &prim_value, CHECK_NULL);
 720     break;
 721 
 722   case JVM_CONSTANT_Long:
 723     assert(cache_index == _no_index_sentinel, "should not have been set");
 724     prim_value.j = this_cp->long_at(index);
 725     result_oop = java_lang_boxing_object::create(T_LONG, &prim_value, CHECK_NULL);
 726     break;
 727 
 728   case JVM_CONSTANT_Double:
 729     assert(cache_index == _no_index_sentinel, "should not have been set");
 730     prim_value.d = this_cp->double_at(index);
 731     result_oop = java_lang_boxing_object::create(T_DOUBLE, &prim_value, CHECK_NULL);
 732     break;
 733 
 734   default:
 735     DEBUG_ONLY( tty->print_cr("*** %p: tag at CP[%d/%d] = %d",
 736                               this_cp(), index, cache_index, tag.value()));
 737     assert(false, "unexpected constant tag");
 738     break;
 739   }
 740 
 741   if (cache_index >= 0) {
 742     // Benign race condition:  resolved_references may already be filled in.
 743     // The important thing here is that all threads pick up the same result.
 744     // It doesn't matter which racing thread wins, as long as only one
 745     // result is used by all threads, and all future queries.
 746     oop old_result = this_cp->resolved_references()->atomic_compare_exchange_oop(cache_index, result_oop, NULL);
 747     if (old_result == NULL) {
 748       return result_oop;  // was installed
 749     } else {
 750       // Return the winning thread's result.  This can be different than
 751       // the result here for MethodHandles.
 752       return old_result;
 753     }
 754   } else {
 755     return result_oop;
 756   }
 757 }
 758 
 759 oop ConstantPool::uncached_string_at(int which, TRAPS) {
 760   Symbol* sym = unresolved_string_at(which);
 761   oop str = StringTable::intern(sym, CHECK_(NULL));
 762   assert(java_lang_String::is_instance(str), "must be string");
 763   return str;
 764 }
 765 
 766 
 767 oop ConstantPool::resolve_bootstrap_specifier_at_impl(const constantPoolHandle& this_cp, int index, TRAPS) {
 768   assert(this_cp->tag_at(index).is_invoke_dynamic(), "Corrupted constant pool");
 769 
 770   Handle bsm;
 771   int argc;
 772   {
 773     // JVM_CONSTANT_InvokeDynamic is an ordered pair of [bootm, name&type], plus optional arguments
 774     // The bootm, being a JVM_CONSTANT_MethodHandle, has its own cache entry.
 775     // It is accompanied by the optional arguments.
 776     int bsm_index = this_cp->invoke_dynamic_bootstrap_method_ref_index_at(index);
 777     oop bsm_oop = this_cp->resolve_possibly_cached_constant_at(bsm_index, CHECK_NULL);
 778     if (!java_lang_invoke_MethodHandle::is_instance(bsm_oop)) {
 779       THROW_MSG_NULL(vmSymbols::java_lang_LinkageError(), "BSM not an MethodHandle");
 780     }
 781 
 782     // Extract the optional static arguments.
 783     argc = this_cp->invoke_dynamic_argument_count_at(index);
 784     if (argc == 0)  return bsm_oop;
 785 
 786     bsm = Handle(THREAD, bsm_oop);
 787   }
 788 
 789   objArrayHandle info;
 790   {
 791     objArrayOop info_oop = oopFactory::new_objArray(SystemDictionary::Object_klass(), 1+argc, CHECK_NULL);
 792     info = objArrayHandle(THREAD, info_oop);
 793   }
 794 
 795   info->obj_at_put(0, bsm());
 796   for (int i = 0; i < argc; i++) {
 797     int arg_index = this_cp->invoke_dynamic_argument_index_at(index, i);
 798     oop arg_oop = this_cp->resolve_possibly_cached_constant_at(arg_index, CHECK_NULL);
 799     info->obj_at_put(1+i, arg_oop);
 800   }
 801 
 802   return info();
 803 }
 804 
 805 oop ConstantPool::string_at_impl(const constantPoolHandle& this_cp, int which, int obj_index, TRAPS) {
 806   // If the string has already been interned, this entry will be non-null
 807   oop str = this_cp->resolved_references()->obj_at(obj_index);
 808   if (str != NULL) return str;
 809   Symbol* sym = this_cp->unresolved_string_at(which);
 810   str = StringTable::intern(sym, CHECK_(NULL));
 811   this_cp->string_at_put(which, obj_index, str);
 812   assert(java_lang_String::is_instance(str), "must be string");
 813   return str;
 814 }
 815 
 816 
 817 bool ConstantPool::klass_name_at_matches(instanceKlassHandle k,
 818                                                 int which) {
 819   // Names are interned, so we can compare Symbol*s directly
 820   Symbol* cp_name = klass_name_at(which);
 821   return (cp_name == k->name());
 822 }
 823 
 824 
 825 // Iterate over symbols and decrement ones which are Symbol*s
 826 // This is done during GC.
 827 // Only decrement the UTF8 symbols. Unresolved classes and strings point to
 828 // these symbols but didn't increment the reference count.
 829 void ConstantPool::unreference_symbols() {
 830   for (int index = 1; index < length(); index++) { // Index 0 is unused
 831     constantTag tag = tag_at(index);
 832     if (tag.is_symbol()) {
 833       symbol_at(index)->decrement_refcount();
 834     }
 835   }
 836 }
 837 
 838 
 839 // Compare this constant pool's entry at index1 to the constant pool
 840 // cp2's entry at index2.
 841 bool ConstantPool::compare_entry_to(int index1, const constantPoolHandle& cp2,
 842        int index2, TRAPS) {
 843 
 844   // The error tags are equivalent to non-error tags when comparing
 845   jbyte t1 = tag_at(index1).non_error_value();
 846   jbyte t2 = cp2->tag_at(index2).non_error_value();
 847 
 848   if (t1 != t2) {
 849     // Not the same entry type so there is nothing else to check. Note
 850     // that this style of checking will consider resolved/unresolved
 851     // class pairs as different.
 852     // From the ConstantPool* API point of view, this is correct
 853     // behavior. See VM_RedefineClasses::merge_constant_pools() to see how this
 854     // plays out in the context of ConstantPool* merging.
 855     return false;
 856   }
 857 
 858   switch (t1) {
 859   case JVM_CONSTANT_Class:
 860   {
 861     Klass* k1 = klass_at(index1, CHECK_false);
 862     Klass* k2 = cp2->klass_at(index2, CHECK_false);
 863     if (k1 == k2) {
 864       return true;
 865     }
 866   } break;
 867 
 868   case JVM_CONSTANT_ClassIndex:
 869   {
 870     int recur1 = klass_index_at(index1);
 871     int recur2 = cp2->klass_index_at(index2);
 872     bool match = compare_entry_to(recur1, cp2, recur2, CHECK_false);
 873     if (match) {
 874       return true;
 875     }
 876   } break;
 877 
 878   case JVM_CONSTANT_Double:
 879   {
 880     jdouble d1 = double_at(index1);
 881     jdouble d2 = cp2->double_at(index2);
 882     if (d1 == d2) {
 883       return true;
 884     }
 885   } break;
 886 
 887   case JVM_CONSTANT_Fieldref:
 888   case JVM_CONSTANT_InterfaceMethodref:
 889   case JVM_CONSTANT_Methodref:
 890   {
 891     int recur1 = uncached_klass_ref_index_at(index1);
 892     int recur2 = cp2->uncached_klass_ref_index_at(index2);
 893     bool match = compare_entry_to(recur1, cp2, recur2, CHECK_false);
 894     if (match) {
 895       recur1 = uncached_name_and_type_ref_index_at(index1);
 896       recur2 = cp2->uncached_name_and_type_ref_index_at(index2);
 897       match = compare_entry_to(recur1, cp2, recur2, CHECK_false);
 898       if (match) {
 899         return true;
 900       }
 901     }
 902   } break;
 903 
 904   case JVM_CONSTANT_Float:
 905   {
 906     jfloat f1 = float_at(index1);
 907     jfloat f2 = cp2->float_at(index2);
 908     if (f1 == f2) {
 909       return true;
 910     }
 911   } break;
 912 
 913   case JVM_CONSTANT_Integer:
 914   {
 915     jint i1 = int_at(index1);
 916     jint i2 = cp2->int_at(index2);
 917     if (i1 == i2) {
 918       return true;
 919     }
 920   } break;
 921 
 922   case JVM_CONSTANT_Long:
 923   {
 924     jlong l1 = long_at(index1);
 925     jlong l2 = cp2->long_at(index2);
 926     if (l1 == l2) {
 927       return true;
 928     }
 929   } break;
 930 
 931   case JVM_CONSTANT_NameAndType:
 932   {
 933     int recur1 = name_ref_index_at(index1);
 934     int recur2 = cp2->name_ref_index_at(index2);
 935     bool match = compare_entry_to(recur1, cp2, recur2, CHECK_false);
 936     if (match) {
 937       recur1 = signature_ref_index_at(index1);
 938       recur2 = cp2->signature_ref_index_at(index2);
 939       match = compare_entry_to(recur1, cp2, recur2, CHECK_false);
 940       if (match) {
 941         return true;
 942       }
 943     }
 944   } break;
 945 
 946   case JVM_CONSTANT_StringIndex:
 947   {
 948     int recur1 = string_index_at(index1);
 949     int recur2 = cp2->string_index_at(index2);
 950     bool match = compare_entry_to(recur1, cp2, recur2, CHECK_false);
 951     if (match) {
 952       return true;
 953     }
 954   } break;
 955 
 956   case JVM_CONSTANT_UnresolvedClass:
 957   {
 958     Symbol* k1 = klass_name_at(index1);
 959     Symbol* k2 = cp2->klass_name_at(index2);
 960     if (k1 == k2) {
 961       return true;
 962     }
 963   } break;
 964 
 965   case JVM_CONSTANT_MethodType:
 966   {
 967     int k1 = method_type_index_at_error_ok(index1);
 968     int k2 = cp2->method_type_index_at_error_ok(index2);
 969     bool match = compare_entry_to(k1, cp2, k2, CHECK_false);
 970     if (match) {
 971       return true;
 972     }
 973   } break;
 974 
 975   case JVM_CONSTANT_MethodHandle:
 976   {
 977     int k1 = method_handle_ref_kind_at_error_ok(index1);
 978     int k2 = cp2->method_handle_ref_kind_at_error_ok(index2);
 979     if (k1 == k2) {
 980       int i1 = method_handle_index_at_error_ok(index1);
 981       int i2 = cp2->method_handle_index_at_error_ok(index2);
 982       bool match = compare_entry_to(i1, cp2, i2, CHECK_false);
 983       if (match) {
 984         return true;
 985       }
 986     }
 987   } break;
 988 
 989   case JVM_CONSTANT_InvokeDynamic:
 990   {
 991     int k1 = invoke_dynamic_name_and_type_ref_index_at(index1);
 992     int k2 = cp2->invoke_dynamic_name_and_type_ref_index_at(index2);
 993     int i1 = invoke_dynamic_bootstrap_specifier_index(index1);
 994     int i2 = cp2->invoke_dynamic_bootstrap_specifier_index(index2);
 995     // separate statements and variables because CHECK_false is used
 996     bool match_entry = compare_entry_to(k1, cp2, k2, CHECK_false);
 997     bool match_operand = compare_operand_to(i1, cp2, i2, CHECK_false);
 998     return (match_entry && match_operand);
 999   } break;
1000 
1001   case JVM_CONSTANT_String:
1002   {
1003     Symbol* s1 = unresolved_string_at(index1);
1004     Symbol* s2 = cp2->unresolved_string_at(index2);
1005     if (s1 == s2) {
1006       return true;
1007     }
1008   } break;
1009 
1010   case JVM_CONSTANT_Utf8:
1011   {
1012     Symbol* s1 = symbol_at(index1);
1013     Symbol* s2 = cp2->symbol_at(index2);
1014     if (s1 == s2) {
1015       return true;
1016     }
1017   } break;
1018 
1019   // Invalid is used as the tag for the second constant pool entry
1020   // occupied by JVM_CONSTANT_Double or JVM_CONSTANT_Long. It should
1021   // not be seen by itself.
1022   case JVM_CONSTANT_Invalid: // fall through
1023 
1024   default:
1025     ShouldNotReachHere();
1026     break;
1027   }
1028 
1029   return false;
1030 } // end compare_entry_to()
1031 
1032 
1033 // Resize the operands array with delta_len and delta_size.
1034 // Used in RedefineClasses for CP merge.
1035 void ConstantPool::resize_operands(int delta_len, int delta_size, TRAPS) {
1036   int old_len  = operand_array_length(operands());
1037   int new_len  = old_len + delta_len;
1038   int min_len  = (delta_len > 0) ? old_len : new_len;
1039 
1040   int old_size = operands()->length();
1041   int new_size = old_size + delta_size;
1042   int min_size = (delta_size > 0) ? old_size : new_size;
1043 
1044   ClassLoaderData* loader_data = pool_holder()->class_loader_data();
1045   Array<u2>* new_ops = MetadataFactory::new_array<u2>(loader_data, new_size, CHECK);
1046 
1047   // Set index in the resized array for existing elements only
1048   for (int idx = 0; idx < min_len; idx++) {
1049     int offset = operand_offset_at(idx);                       // offset in original array
1050     operand_offset_at_put(new_ops, idx, offset + 2*delta_len); // offset in resized array
1051   }
1052   // Copy the bootstrap specifiers only
1053   Copy::conjoint_memory_atomic(operands()->adr_at(2*old_len),
1054                                new_ops->adr_at(2*new_len),
1055                                (min_size - 2*min_len) * sizeof(u2));
1056   // Explicitly deallocate old operands array.
1057   // Note, it is not needed for 7u backport.
1058   if ( operands() != NULL) { // the safety check
1059     MetadataFactory::free_array<u2>(loader_data, operands());
1060   }
1061   set_operands(new_ops);
1062 } // end resize_operands()
1063 
1064 
1065 // Extend the operands array with the length and size of the ext_cp operands.
1066 // Used in RedefineClasses for CP merge.
1067 void ConstantPool::extend_operands(const constantPoolHandle& ext_cp, TRAPS) {
1068   int delta_len = operand_array_length(ext_cp->operands());
1069   if (delta_len == 0) {
1070     return; // nothing to do
1071   }
1072   int delta_size = ext_cp->operands()->length();
1073 
1074   assert(delta_len  > 0 && delta_size > 0, "extended operands array must be bigger");
1075 
1076   if (operand_array_length(operands()) == 0) {
1077     ClassLoaderData* loader_data = pool_holder()->class_loader_data();
1078     Array<u2>* new_ops = MetadataFactory::new_array<u2>(loader_data, delta_size, CHECK);
1079     // The first element index defines the offset of second part
1080     operand_offset_at_put(new_ops, 0, 2*delta_len); // offset in new array
1081     set_operands(new_ops);
1082   } else {
1083     resize_operands(delta_len, delta_size, CHECK);
1084   }
1085 
1086 } // end extend_operands()
1087 
1088 
1089 // Shrink the operands array to a smaller array with new_len length.
1090 // Used in RedefineClasses for CP merge.
1091 void ConstantPool::shrink_operands(int new_len, TRAPS) {
1092   int old_len = operand_array_length(operands());
1093   if (new_len == old_len) {
1094     return; // nothing to do
1095   }
1096   assert(new_len < old_len, "shrunken operands array must be smaller");
1097 
1098   int free_base  = operand_next_offset_at(new_len - 1);
1099   int delta_len  = new_len - old_len;
1100   int delta_size = 2*delta_len + free_base - operands()->length();
1101 
1102   resize_operands(delta_len, delta_size, CHECK);
1103 
1104 } // end shrink_operands()
1105 
1106 
1107 void ConstantPool::copy_operands(const constantPoolHandle& from_cp,
1108                                  const constantPoolHandle& to_cp,
1109                                  TRAPS) {
1110 
1111   int from_oplen = operand_array_length(from_cp->operands());
1112   int old_oplen  = operand_array_length(to_cp->operands());
1113   if (from_oplen != 0) {
1114     ClassLoaderData* loader_data = to_cp->pool_holder()->class_loader_data();
1115     // append my operands to the target's operands array
1116     if (old_oplen == 0) {
1117       // Can't just reuse from_cp's operand list because of deallocation issues
1118       int len = from_cp->operands()->length();
1119       Array<u2>* new_ops = MetadataFactory::new_array<u2>(loader_data, len, CHECK);
1120       Copy::conjoint_memory_atomic(
1121           from_cp->operands()->adr_at(0), new_ops->adr_at(0), len * sizeof(u2));
1122       to_cp->set_operands(new_ops);
1123     } else {
1124       int old_len  = to_cp->operands()->length();
1125       int from_len = from_cp->operands()->length();
1126       int old_off  = old_oplen * sizeof(u2);
1127       int from_off = from_oplen * sizeof(u2);
1128       // Use the metaspace for the destination constant pool
1129       Array<u2>* new_operands = MetadataFactory::new_array<u2>(loader_data, old_len + from_len, CHECK);
1130       int fillp = 0, len = 0;
1131       // first part of dest
1132       Copy::conjoint_memory_atomic(to_cp->operands()->adr_at(0),
1133                                    new_operands->adr_at(fillp),
1134                                    (len = old_off) * sizeof(u2));
1135       fillp += len;
1136       // first part of src
1137       Copy::conjoint_memory_atomic(from_cp->operands()->adr_at(0),
1138                                    new_operands->adr_at(fillp),
1139                                    (len = from_off) * sizeof(u2));
1140       fillp += len;
1141       // second part of dest
1142       Copy::conjoint_memory_atomic(to_cp->operands()->adr_at(old_off),
1143                                    new_operands->adr_at(fillp),
1144                                    (len = old_len - old_off) * sizeof(u2));
1145       fillp += len;
1146       // second part of src
1147       Copy::conjoint_memory_atomic(from_cp->operands()->adr_at(from_off),
1148                                    new_operands->adr_at(fillp),
1149                                    (len = from_len - from_off) * sizeof(u2));
1150       fillp += len;
1151       assert(fillp == new_operands->length(), "");
1152 
1153       // Adjust indexes in the first part of the copied operands array.
1154       for (int j = 0; j < from_oplen; j++) {
1155         int offset = operand_offset_at(new_operands, old_oplen + j);
1156         assert(offset == operand_offset_at(from_cp->operands(), j), "correct copy");
1157         offset += old_len;  // every new tuple is preceded by old_len extra u2's
1158         operand_offset_at_put(new_operands, old_oplen + j, offset);
1159       }
1160 
1161       // replace target operands array with combined array
1162       to_cp->set_operands(new_operands);
1163     }
1164   }
1165 } // end copy_operands()
1166 
1167 
1168 // Copy this constant pool's entries at start_i to end_i (inclusive)
1169 // to the constant pool to_cp's entries starting at to_i. A total of
1170 // (end_i - start_i) + 1 entries are copied.
1171 void ConstantPool::copy_cp_to_impl(const constantPoolHandle& from_cp, int start_i, int end_i,
1172        const constantPoolHandle& to_cp, int to_i, TRAPS) {
1173 
1174 
1175   int dest_i = to_i;  // leave original alone for debug purposes
1176 
1177   for (int src_i = start_i; src_i <= end_i; /* see loop bottom */ ) {
1178     copy_entry_to(from_cp, src_i, to_cp, dest_i, CHECK);
1179 
1180     switch (from_cp->tag_at(src_i).value()) {
1181     case JVM_CONSTANT_Double:
1182     case JVM_CONSTANT_Long:
1183       // double and long take two constant pool entries
1184       src_i += 2;
1185       dest_i += 2;
1186       break;
1187 
1188     default:
1189       // all others take one constant pool entry
1190       src_i++;
1191       dest_i++;
1192       break;
1193     }
1194   }
1195   copy_operands(from_cp, to_cp, CHECK);
1196 
1197 } // end copy_cp_to_impl()
1198 
1199 
1200 // Copy this constant pool's entry at from_i to the constant pool
1201 // to_cp's entry at to_i.
1202 void ConstantPool::copy_entry_to(const constantPoolHandle& from_cp, int from_i,
1203                                         const constantPoolHandle& to_cp, int to_i,
1204                                         TRAPS) {
1205 
1206   int tag = from_cp->tag_at(from_i).value();
1207   switch (tag) {
1208   case JVM_CONSTANT_Class:
1209   {
1210     Klass* k = from_cp->klass_at(from_i, CHECK);
1211     to_cp->klass_at_put(to_i, k);
1212   } break;
1213 
1214   case JVM_CONSTANT_ClassIndex:
1215   {
1216     jint ki = from_cp->klass_index_at(from_i);
1217     to_cp->klass_index_at_put(to_i, ki);
1218   } break;
1219 
1220   case JVM_CONSTANT_Double:
1221   {
1222     jdouble d = from_cp->double_at(from_i);
1223     to_cp->double_at_put(to_i, d);
1224     // double takes two constant pool entries so init second entry's tag
1225     to_cp->tag_at_put(to_i + 1, JVM_CONSTANT_Invalid);
1226   } break;
1227 
1228   case JVM_CONSTANT_Fieldref:
1229   {
1230     int class_index = from_cp->uncached_klass_ref_index_at(from_i);
1231     int name_and_type_index = from_cp->uncached_name_and_type_ref_index_at(from_i);
1232     to_cp->field_at_put(to_i, class_index, name_and_type_index);
1233   } break;
1234 
1235   case JVM_CONSTANT_Float:
1236   {
1237     jfloat f = from_cp->float_at(from_i);
1238     to_cp->float_at_put(to_i, f);
1239   } break;
1240 
1241   case JVM_CONSTANT_Integer:
1242   {
1243     jint i = from_cp->int_at(from_i);
1244     to_cp->int_at_put(to_i, i);
1245   } break;
1246 
1247   case JVM_CONSTANT_InterfaceMethodref:
1248   {
1249     int class_index = from_cp->uncached_klass_ref_index_at(from_i);
1250     int name_and_type_index = from_cp->uncached_name_and_type_ref_index_at(from_i);
1251     to_cp->interface_method_at_put(to_i, class_index, name_and_type_index);
1252   } break;
1253 
1254   case JVM_CONSTANT_Long:
1255   {
1256     jlong l = from_cp->long_at(from_i);
1257     to_cp->long_at_put(to_i, l);
1258     // long takes two constant pool entries so init second entry's tag
1259     to_cp->tag_at_put(to_i + 1, JVM_CONSTANT_Invalid);
1260   } break;
1261 
1262   case JVM_CONSTANT_Methodref:
1263   {
1264     int class_index = from_cp->uncached_klass_ref_index_at(from_i);
1265     int name_and_type_index = from_cp->uncached_name_and_type_ref_index_at(from_i);
1266     to_cp->method_at_put(to_i, class_index, name_and_type_index);
1267   } break;
1268 
1269   case JVM_CONSTANT_NameAndType:
1270   {
1271     int name_ref_index = from_cp->name_ref_index_at(from_i);
1272     int signature_ref_index = from_cp->signature_ref_index_at(from_i);
1273     to_cp->name_and_type_at_put(to_i, name_ref_index, signature_ref_index);
1274   } break;
1275 
1276   case JVM_CONSTANT_StringIndex:
1277   {
1278     jint si = from_cp->string_index_at(from_i);
1279     to_cp->string_index_at_put(to_i, si);
1280   } break;
1281 
1282   case JVM_CONSTANT_UnresolvedClass:
1283   case JVM_CONSTANT_UnresolvedClassInError:
1284   {
1285     // Can be resolved after checking tag, so check the slot first.
1286     CPSlot entry = from_cp->slot_at(from_i);
1287     if (entry.is_resolved()) {
1288       assert(entry.get_klass()->is_klass(), "must be");
1289       // Already resolved
1290       to_cp->klass_at_put(to_i, entry.get_klass());
1291     } else {
1292       to_cp->unresolved_klass_at_put(to_i, entry.get_symbol());
1293     }
1294   } break;
1295 
1296   case JVM_CONSTANT_String:
1297   {
1298     Symbol* s = from_cp->unresolved_string_at(from_i);
1299     to_cp->unresolved_string_at_put(to_i, s);
1300   } break;
1301 
1302   case JVM_CONSTANT_Utf8:
1303   {
1304     Symbol* s = from_cp->symbol_at(from_i);
1305     // Need to increase refcount, the old one will be thrown away and deferenced
1306     s->increment_refcount();
1307     to_cp->symbol_at_put(to_i, s);
1308   } break;
1309 
1310   case JVM_CONSTANT_MethodType:
1311   case JVM_CONSTANT_MethodTypeInError:
1312   {
1313     jint k = from_cp->method_type_index_at_error_ok(from_i);
1314     to_cp->method_type_index_at_put(to_i, k);
1315   } break;
1316 
1317   case JVM_CONSTANT_MethodHandle:
1318   case JVM_CONSTANT_MethodHandleInError:
1319   {
1320     int k1 = from_cp->method_handle_ref_kind_at_error_ok(from_i);
1321     int k2 = from_cp->method_handle_index_at_error_ok(from_i);
1322     to_cp->method_handle_index_at_put(to_i, k1, k2);
1323   } break;
1324 
1325   case JVM_CONSTANT_InvokeDynamic:
1326   {
1327     int k1 = from_cp->invoke_dynamic_bootstrap_specifier_index(from_i);
1328     int k2 = from_cp->invoke_dynamic_name_and_type_ref_index_at(from_i);
1329     k1 += operand_array_length(to_cp->operands());  // to_cp might already have operands
1330     to_cp->invoke_dynamic_at_put(to_i, k1, k2);
1331   } break;
1332 
1333   // Invalid is used as the tag for the second constant pool entry
1334   // occupied by JVM_CONSTANT_Double or JVM_CONSTANT_Long. It should
1335   // not be seen by itself.
1336   case JVM_CONSTANT_Invalid: // fall through
1337 
1338   default:
1339   {
1340     ShouldNotReachHere();
1341   } break;
1342   }
1343 } // end copy_entry_to()
1344 
1345 
1346 // Search constant pool search_cp for an entry that matches this
1347 // constant pool's entry at pattern_i. Returns the index of a
1348 // matching entry or zero (0) if there is no matching entry.
1349 int ConstantPool::find_matching_entry(int pattern_i,
1350       const constantPoolHandle& search_cp, TRAPS) {
1351 
1352   // index zero (0) is not used
1353   for (int i = 1; i < search_cp->length(); i++) {
1354     bool found = compare_entry_to(pattern_i, search_cp, i, CHECK_0);
1355     if (found) {
1356       return i;
1357     }
1358   }
1359 
1360   return 0;  // entry not found; return unused index zero (0)
1361 } // end find_matching_entry()
1362 
1363 
1364 // Compare this constant pool's bootstrap specifier at idx1 to the constant pool
1365 // cp2's bootstrap specifier at idx2.
1366 bool ConstantPool::compare_operand_to(int idx1, const constantPoolHandle& cp2, int idx2, TRAPS) {
1367   int k1 = operand_bootstrap_method_ref_index_at(idx1);
1368   int k2 = cp2->operand_bootstrap_method_ref_index_at(idx2);
1369   bool match = compare_entry_to(k1, cp2, k2, CHECK_false);
1370 
1371   if (!match) {
1372     return false;
1373   }
1374   int argc = operand_argument_count_at(idx1);
1375   if (argc == cp2->operand_argument_count_at(idx2)) {
1376     for (int j = 0; j < argc; j++) {
1377       k1 = operand_argument_index_at(idx1, j);
1378       k2 = cp2->operand_argument_index_at(idx2, j);
1379       match = compare_entry_to(k1, cp2, k2, CHECK_false);
1380       if (!match) {
1381         return false;
1382       }
1383     }
1384     return true;           // got through loop; all elements equal
1385   }
1386   return false;
1387 } // end compare_operand_to()
1388 
1389 // Search constant pool search_cp for a bootstrap specifier that matches
1390 // this constant pool's bootstrap specifier at pattern_i index.
1391 // Return the index of a matching bootstrap specifier or (-1) if there is no match.
1392 int ConstantPool::find_matching_operand(int pattern_i,
1393                     const constantPoolHandle& search_cp, int search_len, TRAPS) {
1394   for (int i = 0; i < search_len; i++) {
1395     bool found = compare_operand_to(pattern_i, search_cp, i, CHECK_(-1));
1396     if (found) {
1397       return i;
1398     }
1399   }
1400   return -1;  // bootstrap specifier not found; return unused index (-1)
1401 } // end find_matching_operand()
1402 
1403 
1404 #ifndef PRODUCT
1405 
1406 const char* ConstantPool::printable_name_at(int which) {
1407 
1408   constantTag tag = tag_at(which);
1409 
1410   if (tag.is_string()) {
1411     return string_at_noresolve(which);
1412   } else if (tag.is_klass() || tag.is_unresolved_klass()) {
1413     return klass_name_at(which)->as_C_string();
1414   } else if (tag.is_symbol()) {
1415     return symbol_at(which)->as_C_string();
1416   }
1417   return "";
1418 }
1419 
1420 #endif // PRODUCT
1421 
1422 
1423 // JVMTI GetConstantPool support
1424 
1425 // For debugging of constant pool
1426 const bool debug_cpool = false;
1427 
1428 #define DBG(code) do { if (debug_cpool) { (code); } } while(0)
1429 
1430 static void print_cpool_bytes(jint cnt, u1 *bytes) {
1431   const char* WARN_MSG = "Must not be such entry!";
1432   jint size = 0;
1433   u2   idx1, idx2;
1434 
1435   for (jint idx = 1; idx < cnt; idx++) {
1436     jint ent_size = 0;
1437     u1   tag  = *bytes++;
1438     size++;                       // count tag
1439 
1440     printf("const #%03d, tag: %02d ", idx, tag);
1441     switch(tag) {
1442       case JVM_CONSTANT_Invalid: {
1443         printf("Invalid");
1444         break;
1445       }
1446       case JVM_CONSTANT_Unicode: {
1447         printf("Unicode      %s", WARN_MSG);
1448         break;
1449       }
1450       case JVM_CONSTANT_Utf8: {
1451         u2 len = Bytes::get_Java_u2(bytes);
1452         char str[128];
1453         if (len > 127) {
1454            len = 127;
1455         }
1456         strncpy(str, (char *) (bytes+2), len);
1457         str[len] = '\0';
1458         printf("Utf8          \"%s\"", str);
1459         ent_size = 2 + len;
1460         break;
1461       }
1462       case JVM_CONSTANT_Integer: {
1463         u4 val = Bytes::get_Java_u4(bytes);
1464         printf("int          %d", *(int *) &val);
1465         ent_size = 4;
1466         break;
1467       }
1468       case JVM_CONSTANT_Float: {
1469         u4 val = Bytes::get_Java_u4(bytes);
1470         printf("float        %5.3ff", *(float *) &val);
1471         ent_size = 4;
1472         break;
1473       }
1474       case JVM_CONSTANT_Long: {
1475         u8 val = Bytes::get_Java_u8(bytes);
1476         printf("long         " INT64_FORMAT, (int64_t) *(jlong *) &val);
1477         ent_size = 8;
1478         idx++; // Long takes two cpool slots
1479         break;
1480       }
1481       case JVM_CONSTANT_Double: {
1482         u8 val = Bytes::get_Java_u8(bytes);
1483         printf("double       %5.3fd", *(jdouble *)&val);
1484         ent_size = 8;
1485         idx++; // Double takes two cpool slots
1486         break;
1487       }
1488       case JVM_CONSTANT_Class: {
1489         idx1 = Bytes::get_Java_u2(bytes);
1490         printf("class        #%03d", idx1);
1491         ent_size = 2;
1492         break;
1493       }
1494       case JVM_CONSTANT_String: {
1495         idx1 = Bytes::get_Java_u2(bytes);
1496         printf("String       #%03d", idx1);
1497         ent_size = 2;
1498         break;
1499       }
1500       case JVM_CONSTANT_Fieldref: {
1501         idx1 = Bytes::get_Java_u2(bytes);
1502         idx2 = Bytes::get_Java_u2(bytes+2);
1503         printf("Field        #%03d, #%03d", (int) idx1, (int) idx2);
1504         ent_size = 4;
1505         break;
1506       }
1507       case JVM_CONSTANT_Methodref: {
1508         idx1 = Bytes::get_Java_u2(bytes);
1509         idx2 = Bytes::get_Java_u2(bytes+2);
1510         printf("Method       #%03d, #%03d", idx1, idx2);
1511         ent_size = 4;
1512         break;
1513       }
1514       case JVM_CONSTANT_InterfaceMethodref: {
1515         idx1 = Bytes::get_Java_u2(bytes);
1516         idx2 = Bytes::get_Java_u2(bytes+2);
1517         printf("InterfMethod #%03d, #%03d", idx1, idx2);
1518         ent_size = 4;
1519         break;
1520       }
1521       case JVM_CONSTANT_NameAndType: {
1522         idx1 = Bytes::get_Java_u2(bytes);
1523         idx2 = Bytes::get_Java_u2(bytes+2);
1524         printf("NameAndType  #%03d, #%03d", idx1, idx2);
1525         ent_size = 4;
1526         break;
1527       }
1528       case JVM_CONSTANT_ClassIndex: {
1529         printf("ClassIndex  %s", WARN_MSG);
1530         break;
1531       }
1532       case JVM_CONSTANT_UnresolvedClass: {
1533         printf("UnresolvedClass: %s", WARN_MSG);
1534         break;
1535       }
1536       case JVM_CONSTANT_UnresolvedClassInError: {
1537         printf("UnresolvedClassInErr: %s", WARN_MSG);
1538         break;
1539       }
1540       case JVM_CONSTANT_StringIndex: {
1541         printf("StringIndex: %s", WARN_MSG);
1542         break;
1543       }
1544     }
1545     printf(";\n");
1546     bytes += ent_size;
1547     size  += ent_size;
1548   }
1549   printf("Cpool size: %d\n", size);
1550   fflush(0);
1551   return;
1552 } /* end print_cpool_bytes */
1553 
1554 
1555 // Returns size of constant pool entry.
1556 jint ConstantPool::cpool_entry_size(jint idx) {
1557   switch(tag_at(idx).value()) {
1558     case JVM_CONSTANT_Invalid:
1559     case JVM_CONSTANT_Unicode:
1560       return 1;
1561 
1562     case JVM_CONSTANT_Utf8:
1563       return 3 + symbol_at(idx)->utf8_length();
1564 
1565     case JVM_CONSTANT_Class:
1566     case JVM_CONSTANT_String:
1567     case JVM_CONSTANT_ClassIndex:
1568     case JVM_CONSTANT_UnresolvedClass:
1569     case JVM_CONSTANT_UnresolvedClassInError:
1570     case JVM_CONSTANT_StringIndex:
1571     case JVM_CONSTANT_MethodType:
1572     case JVM_CONSTANT_MethodTypeInError:
1573       return 3;
1574 
1575     case JVM_CONSTANT_MethodHandle:
1576     case JVM_CONSTANT_MethodHandleInError:
1577       return 4; //tag, ref_kind, ref_index
1578 
1579     case JVM_CONSTANT_Integer:
1580     case JVM_CONSTANT_Float:
1581     case JVM_CONSTANT_Fieldref:
1582     case JVM_CONSTANT_Methodref:
1583     case JVM_CONSTANT_InterfaceMethodref:
1584     case JVM_CONSTANT_NameAndType:
1585       return 5;
1586 
1587     case JVM_CONSTANT_InvokeDynamic:
1588       // u1 tag, u2 bsm, u2 nt
1589       return 5;
1590 
1591     case JVM_CONSTANT_Long:
1592     case JVM_CONSTANT_Double:
1593       return 9;
1594   }
1595   assert(false, "cpool_entry_size: Invalid constant pool entry tag");
1596   return 1;
1597 } /* end cpool_entry_size */
1598 
1599 
1600 // SymbolHashMap is used to find a constant pool index from a string.
1601 // This function fills in SymbolHashMaps, one for utf8s and one for
1602 // class names, returns size of the cpool raw bytes.
1603 jint ConstantPool::hash_entries_to(SymbolHashMap *symmap,
1604                                           SymbolHashMap *classmap) {
1605   jint size = 0;
1606 
1607   for (u2 idx = 1; idx < length(); idx++) {
1608     u2 tag = tag_at(idx).value();
1609     size += cpool_entry_size(idx);
1610 
1611     switch(tag) {
1612       case JVM_CONSTANT_Utf8: {
1613         Symbol* sym = symbol_at(idx);
1614         symmap->add_entry(sym, idx);
1615         DBG(printf("adding symbol entry %s = %d\n", sym->as_utf8(), idx));
1616         break;
1617       }
1618       case JVM_CONSTANT_Class:
1619       case JVM_CONSTANT_UnresolvedClass:
1620       case JVM_CONSTANT_UnresolvedClassInError: {
1621         Symbol* sym = klass_name_at(idx);
1622         classmap->add_entry(sym, idx);
1623         DBG(printf("adding class entry %s = %d\n", sym->as_utf8(), idx));
1624         break;
1625       }
1626       case JVM_CONSTANT_Long:
1627       case JVM_CONSTANT_Double: {
1628         idx++; // Both Long and Double take two cpool slots
1629         break;
1630       }
1631     }
1632   }
1633   return size;
1634 } /* end hash_utf8_entries_to */
1635 
1636 
1637 // Copy cpool bytes.
1638 // Returns:
1639 //    0, in case of OutOfMemoryError
1640 //   -1, in case of internal error
1641 //  > 0, count of the raw cpool bytes that have been copied
1642 int ConstantPool::copy_cpool_bytes(int cpool_size,
1643                                           SymbolHashMap* tbl,
1644                                           unsigned char *bytes) {
1645   u2   idx1, idx2;
1646   jint size  = 0;
1647   jint cnt   = length();
1648   unsigned char *start_bytes = bytes;
1649 
1650   for (jint idx = 1; idx < cnt; idx++) {
1651     u1   tag      = tag_at(idx).value();
1652     jint ent_size = cpool_entry_size(idx);
1653 
1654     assert(size + ent_size <= cpool_size, "Size mismatch");
1655 
1656     *bytes = tag;
1657     DBG(printf("#%03hd tag=%03hd, ", idx, tag));
1658     switch(tag) {
1659       case JVM_CONSTANT_Invalid: {
1660         DBG(printf("JVM_CONSTANT_Invalid"));
1661         break;
1662       }
1663       case JVM_CONSTANT_Unicode: {
1664         assert(false, "Wrong constant pool tag: JVM_CONSTANT_Unicode");
1665         DBG(printf("JVM_CONSTANT_Unicode"));
1666         break;
1667       }
1668       case JVM_CONSTANT_Utf8: {
1669         Symbol* sym = symbol_at(idx);
1670         char*     str = sym->as_utf8();
1671         // Warning! It's crashing on x86 with len = sym->utf8_length()
1672         int       len = (int) strlen(str);
1673         Bytes::put_Java_u2((address) (bytes+1), (u2) len);
1674         for (int i = 0; i < len; i++) {
1675             bytes[3+i] = (u1) str[i];
1676         }
1677         DBG(printf("JVM_CONSTANT_Utf8: %s ", str));
1678         break;
1679       }
1680       case JVM_CONSTANT_Integer: {
1681         jint val = int_at(idx);
1682         Bytes::put_Java_u4((address) (bytes+1), *(u4*)&val);
1683         break;
1684       }
1685       case JVM_CONSTANT_Float: {
1686         jfloat val = float_at(idx);
1687         Bytes::put_Java_u4((address) (bytes+1), *(u4*)&val);
1688         break;
1689       }
1690       case JVM_CONSTANT_Long: {
1691         jlong val = long_at(idx);
1692         Bytes::put_Java_u8((address) (bytes+1), *(u8*)&val);
1693         idx++;             // Long takes two cpool slots
1694         break;
1695       }
1696       case JVM_CONSTANT_Double: {
1697         jdouble val = double_at(idx);
1698         Bytes::put_Java_u8((address) (bytes+1), *(u8*)&val);
1699         idx++;             // Double takes two cpool slots
1700         break;
1701       }
1702       case JVM_CONSTANT_Class:
1703       case JVM_CONSTANT_UnresolvedClass:
1704       case JVM_CONSTANT_UnresolvedClassInError: {
1705         *bytes = JVM_CONSTANT_Class;
1706         Symbol* sym = klass_name_at(idx);
1707         idx1 = tbl->symbol_to_value(sym);
1708         assert(idx1 != 0, "Have not found a hashtable entry");
1709         Bytes::put_Java_u2((address) (bytes+1), idx1);
1710         DBG(printf("JVM_CONSTANT_Class: idx=#%03hd, %s", idx1, sym->as_utf8()));
1711         break;
1712       }
1713       case JVM_CONSTANT_String: {
1714         *bytes = JVM_CONSTANT_String;
1715         Symbol* sym = unresolved_string_at(idx);
1716         idx1 = tbl->symbol_to_value(sym);
1717         assert(idx1 != 0, "Have not found a hashtable entry");
1718         Bytes::put_Java_u2((address) (bytes+1), idx1);
1719         DBG(printf("JVM_CONSTANT_String: idx=#%03hd, %s", idx1, sym->as_utf8()));
1720         break;
1721       }
1722       case JVM_CONSTANT_Fieldref:
1723       case JVM_CONSTANT_Methodref:
1724       case JVM_CONSTANT_InterfaceMethodref: {
1725         idx1 = uncached_klass_ref_index_at(idx);
1726         idx2 = uncached_name_and_type_ref_index_at(idx);
1727         Bytes::put_Java_u2((address) (bytes+1), idx1);
1728         Bytes::put_Java_u2((address) (bytes+3), idx2);
1729         DBG(printf("JVM_CONSTANT_Methodref: %hd %hd", idx1, idx2));
1730         break;
1731       }
1732       case JVM_CONSTANT_NameAndType: {
1733         idx1 = name_ref_index_at(idx);
1734         idx2 = signature_ref_index_at(idx);
1735         Bytes::put_Java_u2((address) (bytes+1), idx1);
1736         Bytes::put_Java_u2((address) (bytes+3), idx2);
1737         DBG(printf("JVM_CONSTANT_NameAndType: %hd %hd", idx1, idx2));
1738         break;
1739       }
1740       case JVM_CONSTANT_ClassIndex: {
1741         *bytes = JVM_CONSTANT_Class;
1742         idx1 = klass_index_at(idx);
1743         Bytes::put_Java_u2((address) (bytes+1), idx1);
1744         DBG(printf("JVM_CONSTANT_ClassIndex: %hd", idx1));
1745         break;
1746       }
1747       case JVM_CONSTANT_StringIndex: {
1748         *bytes = JVM_CONSTANT_String;
1749         idx1 = string_index_at(idx);
1750         Bytes::put_Java_u2((address) (bytes+1), idx1);
1751         DBG(printf("JVM_CONSTANT_StringIndex: %hd", idx1));
1752         break;
1753       }
1754       case JVM_CONSTANT_MethodHandle:
1755       case JVM_CONSTANT_MethodHandleInError: {
1756         *bytes = JVM_CONSTANT_MethodHandle;
1757         int kind = method_handle_ref_kind_at_error_ok(idx);
1758         idx1 = method_handle_index_at_error_ok(idx);
1759         *(bytes+1) = (unsigned char) kind;
1760         Bytes::put_Java_u2((address) (bytes+2), idx1);
1761         DBG(printf("JVM_CONSTANT_MethodHandle: %d %hd", kind, idx1));
1762         break;
1763       }
1764       case JVM_CONSTANT_MethodType:
1765       case JVM_CONSTANT_MethodTypeInError: {
1766         *bytes = JVM_CONSTANT_MethodType;
1767         idx1 = method_type_index_at_error_ok(idx);
1768         Bytes::put_Java_u2((address) (bytes+1), idx1);
1769         DBG(printf("JVM_CONSTANT_MethodType: %hd", idx1));
1770         break;
1771       }
1772       case JVM_CONSTANT_InvokeDynamic: {
1773         *bytes = tag;
1774         idx1 = extract_low_short_from_int(*int_at_addr(idx));
1775         idx2 = extract_high_short_from_int(*int_at_addr(idx));
1776         assert(idx2 == invoke_dynamic_name_and_type_ref_index_at(idx), "correct half of u4");
1777         Bytes::put_Java_u2((address) (bytes+1), idx1);
1778         Bytes::put_Java_u2((address) (bytes+3), idx2);
1779         DBG(printf("JVM_CONSTANT_InvokeDynamic: %hd %hd", idx1, idx2));
1780         break;
1781       }
1782     }
1783     DBG(printf("\n"));
1784     bytes += ent_size;
1785     size  += ent_size;
1786   }
1787   assert(size == cpool_size, "Size mismatch");
1788 
1789   // Keep temorarily for debugging until it's stable.
1790   DBG(print_cpool_bytes(cnt, start_bytes));
1791   return (int)(bytes - start_bytes);
1792 } /* end copy_cpool_bytes */
1793 
1794 #undef DBG
1795 
1796 
1797 void ConstantPool::set_on_stack(const bool value) {
1798   if (value) {
1799     // Only record if it's not already set.
1800     if (!on_stack()) {
1801       _flags |= _on_stack;
1802       MetadataOnStackMark::record(this);
1803     }
1804   } else {
1805     // Clearing is done single-threadedly.
1806     _flags &= ~_on_stack;
1807   }
1808 }
1809 
1810 // JSR 292 support for patching constant pool oops after the class is linked and
1811 // the oop array for resolved references are created.
1812 // We can't do this during classfile parsing, which is how the other indexes are
1813 // patched.  The other patches are applied early for some error checking
1814 // so only defer the pseudo_strings.
1815 void ConstantPool::patch_resolved_references(GrowableArray<Handle>* cp_patches) {
1816   for (int index = 1; index < cp_patches->length(); index++) { // Index 0 is unused
1817     Handle patch = cp_patches->at(index);
1818     if (patch.not_null()) {
1819       assert (tag_at(index).is_string(), "should only be string left");
1820       // Patching a string means pre-resolving it.
1821       // The spelling in the constant pool is ignored.
1822       // The constant reference may be any object whatever.
1823       // If it is not a real interned string, the constant is referred
1824       // to as a "pseudo-string", and must be presented to the CP
1825       // explicitly, because it may require scavenging.
1826       int obj_index = cp_to_object_index(index);
1827       pseudo_string_at_put(index, obj_index, patch());
1828      DEBUG_ONLY(cp_patches->at_put(index, Handle());)
1829     }
1830   }
1831 #ifdef ASSERT
1832   // Ensure that all the patches have been used.
1833   for (int index = 0; index < cp_patches->length(); index++) {
1834     assert(cp_patches->at(index).is_null(),
1835            "Unused constant pool patch at %d in class file %s",
1836            index,
1837            pool_holder()->external_name());
1838   }
1839 #endif // ASSERT
1840 }
1841 
1842 #ifndef PRODUCT
1843 
1844 // CompileTheWorld support. Preload all classes loaded references in the passed in constantpool
1845 void ConstantPool::preload_and_initialize_all_classes(ConstantPool* obj, TRAPS) {
1846   guarantee(obj->is_constantPool(), "object must be constant pool");
1847   constantPoolHandle cp(THREAD, (ConstantPool*)obj);
1848   guarantee(cp->pool_holder() != NULL, "must be fully loaded");
1849 
1850   for (int i = 0; i< cp->length();  i++) {
1851     if (cp->tag_at(i).is_unresolved_klass()) {
1852       // This will force loading of the class
1853       Klass* klass = cp->klass_at(i, CHECK);
1854       if (klass->is_instance_klass()) {
1855         // Force initialization of class
1856         InstanceKlass::cast(klass)->initialize(CHECK);
1857       }
1858     }
1859   }
1860 }
1861 
1862 #endif
1863 
1864 
1865 // Printing
1866 
1867 void ConstantPool::print_on(outputStream* st) const {
1868   assert(is_constantPool(), "must be constantPool");
1869   st->print_cr("%s", internal_name());
1870   if (flags() != 0) {
1871     st->print(" - flags: 0x%x", flags());
1872     if (has_preresolution()) st->print(" has_preresolution");
1873     if (on_stack()) st->print(" on_stack");
1874     st->cr();
1875   }
1876   if (pool_holder() != NULL) {
1877     st->print_cr(" - holder: " INTPTR_FORMAT, p2i(pool_holder()));
1878   }
1879   st->print_cr(" - cache: " INTPTR_FORMAT, p2i(cache()));
1880   st->print_cr(" - resolved_references: " INTPTR_FORMAT, p2i(resolved_references()));
1881   st->print_cr(" - reference_map: " INTPTR_FORMAT, p2i(reference_map()));
1882 
1883   for (int index = 1; index < length(); index++) {      // Index 0 is unused
1884     ((ConstantPool*)this)->print_entry_on(index, st);
1885     switch (tag_at(index).value()) {
1886       case JVM_CONSTANT_Long :
1887       case JVM_CONSTANT_Double :
1888         index++;   // Skip entry following eigth-byte constant
1889     }
1890 
1891   }
1892   st->cr();
1893 }
1894 
1895 // Print one constant pool entry
1896 void ConstantPool::print_entry_on(const int index, outputStream* st) {
1897   EXCEPTION_MARK;
1898   st->print(" - %3d : ", index);
1899   tag_at(index).print_on(st);
1900   st->print(" : ");
1901   switch (tag_at(index).value()) {
1902     case JVM_CONSTANT_Class :
1903       { Klass* k = klass_at(index, CATCH);
1904         guarantee(k != NULL, "need klass");
1905         k->print_value_on(st);
1906         st->print(" {" PTR_FORMAT "}", p2i(k));
1907       }
1908       break;
1909     case JVM_CONSTANT_Fieldref :
1910     case JVM_CONSTANT_Methodref :
1911     case JVM_CONSTANT_InterfaceMethodref :
1912       st->print("klass_index=%d", uncached_klass_ref_index_at(index));
1913       st->print(" name_and_type_index=%d", uncached_name_and_type_ref_index_at(index));
1914       break;
1915     case JVM_CONSTANT_String :
1916       if (is_pseudo_string_at(index)) {
1917         oop anObj = pseudo_string_at(index);
1918         anObj->print_value_on(st);
1919         st->print(" {" PTR_FORMAT "}", p2i(anObj));
1920       } else {
1921         unresolved_string_at(index)->print_value_on(st);
1922       }
1923       break;
1924     case JVM_CONSTANT_Integer :
1925       st->print("%d", int_at(index));
1926       break;
1927     case JVM_CONSTANT_Float :
1928       st->print("%f", float_at(index));
1929       break;
1930     case JVM_CONSTANT_Long :
1931       st->print_jlong(long_at(index));
1932       break;
1933     case JVM_CONSTANT_Double :
1934       st->print("%lf", double_at(index));
1935       break;
1936     case JVM_CONSTANT_NameAndType :
1937       st->print("name_index=%d", name_ref_index_at(index));
1938       st->print(" signature_index=%d", signature_ref_index_at(index));
1939       break;
1940     case JVM_CONSTANT_Utf8 :
1941       symbol_at(index)->print_value_on(st);
1942       break;
1943     case JVM_CONSTANT_UnresolvedClass :               // fall-through
1944     case JVM_CONSTANT_UnresolvedClassInError: {
1945       CPSlot entry = slot_at(index);
1946       if (entry.is_resolved()) {
1947         entry.get_klass()->print_value_on(st);
1948       } else {
1949         entry.get_symbol()->print_value_on(st);
1950       }
1951       }
1952       break;
1953     case JVM_CONSTANT_MethodHandle :
1954     case JVM_CONSTANT_MethodHandleInError :
1955       st->print("ref_kind=%d", method_handle_ref_kind_at_error_ok(index));
1956       st->print(" ref_index=%d", method_handle_index_at_error_ok(index));
1957       break;
1958     case JVM_CONSTANT_MethodType :
1959     case JVM_CONSTANT_MethodTypeInError :
1960       st->print("signature_index=%d", method_type_index_at_error_ok(index));
1961       break;
1962     case JVM_CONSTANT_InvokeDynamic :
1963       {
1964         st->print("bootstrap_method_index=%d", invoke_dynamic_bootstrap_method_ref_index_at(index));
1965         st->print(" name_and_type_index=%d", invoke_dynamic_name_and_type_ref_index_at(index));
1966         int argc = invoke_dynamic_argument_count_at(index);
1967         if (argc > 0) {
1968           for (int arg_i = 0; arg_i < argc; arg_i++) {
1969             int arg = invoke_dynamic_argument_index_at(index, arg_i);
1970             st->print((arg_i == 0 ? " arguments={%d" : ", %d"), arg);
1971           }
1972           st->print("}");
1973         }
1974       }
1975       break;
1976     default:
1977       ShouldNotReachHere();
1978       break;
1979   }
1980   st->cr();
1981 }
1982 
1983 void ConstantPool::print_value_on(outputStream* st) const {
1984   assert(is_constantPool(), "must be constantPool");
1985   st->print("constant pool [%d]", length());
1986   if (has_preresolution()) st->print("/preresolution");
1987   if (operands() != NULL)  st->print("/operands[%d]", operands()->length());
1988   print_address_on(st);
1989   st->print(" for ");
1990   pool_holder()->print_value_on(st);
1991   if (pool_holder() != NULL) {
1992     bool extra = (pool_holder()->constants() != this);
1993     if (extra)  st->print(" (extra)");
1994   }
1995   if (cache() != NULL) {
1996     st->print(" cache=" PTR_FORMAT, p2i(cache()));
1997   }
1998 }
1999 
2000 #if INCLUDE_SERVICES
2001 // Size Statistics
2002 void ConstantPool::collect_statistics(KlassSizeStats *sz) const {
2003   sz->_cp_all_bytes += (sz->_cp_bytes          = sz->count(this));
2004   sz->_cp_all_bytes += (sz->_cp_tags_bytes     = sz->count_array(tags()));
2005   sz->_cp_all_bytes += (sz->_cp_cache_bytes    = sz->count(cache()));
2006   sz->_cp_all_bytes += (sz->_cp_operands_bytes = sz->count_array(operands()));
2007   sz->_cp_all_bytes += (sz->_cp_refmap_bytes   = sz->count_array(reference_map()));
2008 
2009   sz->_ro_bytes += sz->_cp_operands_bytes + sz->_cp_tags_bytes +
2010                    sz->_cp_refmap_bytes;
2011   sz->_rw_bytes += sz->_cp_bytes + sz->_cp_cache_bytes;
2012 }
2013 #endif // INCLUDE_SERVICES
2014 
2015 // Verification
2016 
2017 void ConstantPool::verify_on(outputStream* st) {
2018   guarantee(is_constantPool(), "object must be constant pool");
2019   for (int i = 0; i< length();  i++) {
2020     constantTag tag = tag_at(i);
2021     CPSlot entry = slot_at(i);
2022     if (tag.is_klass()) {
2023       if (entry.is_resolved()) {
2024         guarantee(entry.get_klass()->is_klass(),    "should be klass");
2025       }
2026     } else if (tag.is_unresolved_klass()) {
2027       if (entry.is_resolved()) {
2028         guarantee(entry.get_klass()->is_klass(),    "should be klass");
2029       }
2030     } else if (tag.is_symbol()) {
2031       guarantee(entry.get_symbol()->refcount() != 0, "should have nonzero reference count");
2032     } else if (tag.is_string()) {
2033       guarantee(entry.get_symbol()->refcount() != 0, "should have nonzero reference count");
2034     }
2035   }
2036   if (cache() != NULL) {
2037     // Note: cache() can be NULL before a class is completely setup or
2038     // in temporary constant pools used during constant pool merging
2039     guarantee(cache()->is_constantPoolCache(), "should be constant pool cache");
2040   }
2041   if (pool_holder() != NULL) {
2042     // Note: pool_holder() can be NULL in temporary constant pools
2043     // used during constant pool merging
2044     guarantee(pool_holder()->is_klass(),    "should be klass");
2045   }
2046 }
2047 
2048 
2049 void SymbolHashMap::add_entry(Symbol* sym, u2 value) {
2050   char *str = sym->as_utf8();
2051   unsigned int hash = compute_hash(str, sym->utf8_length());
2052   unsigned int index = hash % table_size();
2053 
2054   // check if already in map
2055   // we prefer the first entry since it is more likely to be what was used in
2056   // the class file
2057   for (SymbolHashMapEntry *en = bucket(index); en != NULL; en = en->next()) {
2058     assert(en->symbol() != NULL, "SymbolHashMapEntry symbol is NULL");
2059     if (en->hash() == hash && en->symbol() == sym) {
2060         return;  // already there
2061     }
2062   }
2063 
2064   SymbolHashMapEntry* entry = new SymbolHashMapEntry(hash, sym, value);
2065   entry->set_next(bucket(index));
2066   _buckets[index].set_entry(entry);
2067   assert(entry->symbol() != NULL, "SymbolHashMapEntry symbol is NULL");
2068 }
2069 
2070 SymbolHashMapEntry* SymbolHashMap::find_entry(Symbol* sym) {
2071   assert(sym != NULL, "SymbolHashMap::find_entry - symbol is NULL");
2072   char *str = sym->as_utf8();
2073   int   len = sym->utf8_length();
2074   unsigned int hash = SymbolHashMap::compute_hash(str, len);
2075   unsigned int index = hash % table_size();
2076   for (SymbolHashMapEntry *en = bucket(index); en != NULL; en = en->next()) {
2077     assert(en->symbol() != NULL, "SymbolHashMapEntry symbol is NULL");
2078     if (en->hash() == hash && en->symbol() == sym) {
2079       return en;
2080     }
2081   }
2082   return NULL;
2083 }