1 /*
   2  * Copyright (c) 1997, 2019, 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 "jvm.h"
  27 #include "classfile/classLoaderData.hpp"
  28 #include "classfile/javaClasses.inline.hpp"
  29 #include "classfile/metadataOnStackMark.hpp"
  30 #include "classfile/stringTable.hpp"
  31 #include "classfile/systemDictionary.hpp"
  32 #include "classfile/vmSymbols.hpp"
  33 #include "interpreter/linkResolver.hpp"
  34 #include "memory/allocation.inline.hpp"
  35 #include "memory/heapInspection.hpp"
  36 #include "memory/heapShared.hpp"
  37 #include "memory/metadataFactory.hpp"
  38 #include "memory/metaspaceClosure.hpp"
  39 #include "memory/metaspaceShared.hpp"
  40 #include "memory/oopFactory.hpp"
  41 #include "memory/resourceArea.hpp"
  42 #include "oops/array.hpp"
  43 #include "oops/constantPool.inline.hpp"
  44 #include "oops/cpCache.inline.hpp"
  45 #include "oops/instanceKlass.hpp"
  46 #include "oops/objArrayKlass.hpp"
  47 #include "oops/objArrayOop.inline.hpp"
  48 #include "oops/oop.inline.hpp"
  49 #include "oops/typeArrayOop.inline.hpp"
  50 #include "oops/valueArrayKlass.hpp"
  51 #include "runtime/fieldType.hpp"
  52 #include "runtime/handles.inline.hpp"
  53 #include "runtime/init.hpp"
  54 #include "runtime/javaCalls.hpp"
  55 #include "runtime/signature.hpp"
  56 #include "runtime/thread.inline.hpp"
  57 #include "runtime/vframe.inline.hpp"
  58 #include "utilities/copy.hpp"
  59 
  60 ConstantPool* ConstantPool::allocate(ClassLoaderData* loader_data, int length, TRAPS) {
  61   Array<u1>* tags = MetadataFactory::new_array<u1>(loader_data, length, 0, CHECK_NULL);
  62   int size = ConstantPool::size(length);
  63   return new (loader_data, size, MetaspaceObj::ConstantPoolType, THREAD) ConstantPool(tags);
  64 }
  65 
  66 #ifdef ASSERT
  67 
  68 // MetaspaceObj allocation invariant is calloc equivalent memory
  69 // simple verification of this here (JVM_CONSTANT_Invalid == 0 )
  70 static bool tag_array_is_zero_initialized(Array<u1>* tags) {
  71   assert(tags != NULL, "invariant");
  72   const int length = tags->length();
  73   for (int index = 0; index < length; ++index) {
  74     if (JVM_CONSTANT_Invalid != tags->at(index)) {
  75       return false;
  76     }
  77   }
  78   return true;
  79 }
  80 
  81 #endif
  82 
  83 ConstantPool::ConstantPool(Array<u1>* tags) :
  84   _tags(tags),
  85   _length(tags->length()) {
  86 
  87     assert(_tags != NULL, "invariant");
  88     assert(tags->length() == _length, "invariant");
  89     assert(tag_array_is_zero_initialized(tags), "invariant");
  90     assert(0 == flags(), "invariant");
  91     assert(0 == version(), "invariant");
  92     assert(NULL == _pool_holder, "invariant");
  93 }
  94 
  95 void ConstantPool::deallocate_contents(ClassLoaderData* loader_data) {
  96   if (cache() != NULL) {
  97     MetadataFactory::free_metadata(loader_data, cache());
  98     set_cache(NULL);
  99   }
 100 
 101   MetadataFactory::free_array<Klass*>(loader_data, resolved_klasses());
 102   set_resolved_klasses(NULL);
 103 
 104   MetadataFactory::free_array<jushort>(loader_data, operands());
 105   set_operands(NULL);
 106 
 107   release_C_heap_structures();
 108 
 109   // free tag array
 110   MetadataFactory::free_array<u1>(loader_data, tags());
 111   set_tags(NULL);
 112 }
 113 
 114 void ConstantPool::release_C_heap_structures() {
 115   // walk constant pool and decrement symbol reference counts
 116   unreference_symbols();
 117 }
 118 
 119 void ConstantPool::metaspace_pointers_do(MetaspaceClosure* it) {
 120   log_trace(cds)("Iter(ConstantPool): %p", this);
 121 
 122   it->push(&_tags, MetaspaceClosure::_writable);
 123   it->push(&_cache);
 124   it->push(&_pool_holder);
 125   it->push(&_operands);
 126   it->push(&_resolved_klasses, MetaspaceClosure::_writable);
 127 
 128   for (int i = 0; i < length(); i++) {
 129     // The only MSO's embedded in the CP entries are Symbols:
 130     //   JVM_CONSTANT_String (normal and pseudo)
 131     //   JVM_CONSTANT_Utf8
 132     constantTag ctag = tag_at(i);
 133     if (ctag.is_string() || ctag.is_utf8()) {
 134       it->push(symbol_at_addr(i));
 135     }
 136   }
 137 }
 138 
 139 objArrayOop ConstantPool::resolved_references() const {
 140   return (objArrayOop)_cache->resolved_references();
 141 }
 142 
 143 // Called from outside constant pool resolution where a resolved_reference array
 144 // may not be present.
 145 objArrayOop ConstantPool::resolved_references_or_null() const {
 146   if (_cache == NULL) {
 147     return NULL;
 148   } else {
 149     return (objArrayOop)_cache->resolved_references();
 150   }
 151 }
 152 
 153 // Create resolved_references array and mapping array for original cp indexes
 154 // The ldc bytecode was rewritten to have the resolved reference array index so need a way
 155 // to map it back for resolving and some unlikely miscellaneous uses.
 156 // The objects created by invokedynamic are appended to this list.
 157 void ConstantPool::initialize_resolved_references(ClassLoaderData* loader_data,
 158                                                   const intStack& reference_map,
 159                                                   int constant_pool_map_length,
 160                                                   TRAPS) {
 161   // Initialized the resolved object cache.
 162   int map_length = reference_map.length();
 163   if (map_length > 0) {
 164     // Only need mapping back to constant pool entries.  The map isn't used for
 165     // invokedynamic resolved_reference entries.  For invokedynamic entries,
 166     // the constant pool cache index has the mapping back to both the constant
 167     // pool and to the resolved reference index.
 168     if (constant_pool_map_length > 0) {
 169       Array<u2>* om = MetadataFactory::new_array<u2>(loader_data, constant_pool_map_length, CHECK);
 170 
 171       for (int i = 0; i < constant_pool_map_length; i++) {
 172         int x = reference_map.at(i);
 173         assert(x == (int)(jushort) x, "klass index is too big");
 174         om->at_put(i, (jushort)x);
 175       }
 176       set_reference_map(om);
 177     }
 178 
 179     // Create Java array for holding resolved strings, methodHandles,
 180     // methodTypes, invokedynamic and invokehandle appendix objects, etc.
 181     objArrayOop stom = oopFactory::new_objArray(SystemDictionary::Object_klass(), map_length, CHECK);
 182     Handle refs_handle (THREAD, (oop)stom);  // must handleize.
 183     set_resolved_references(loader_data->add_handle(refs_handle));
 184   }
 185 }
 186 
 187 void ConstantPool::allocate_resolved_klasses(ClassLoaderData* loader_data, int num_klasses, TRAPS) {
 188   // A ConstantPool can't possibly have 0xffff valid class entries,
 189   // because entry #0 must be CONSTANT_Invalid, and each class entry must refer to a UTF8
 190   // entry for the class's name. So at most we will have 0xfffe class entries.
 191   // This allows us to use 0xffff (ConstantPool::_temp_resolved_klass_index) to indicate
 192   // UnresolvedKlass entries that are temporarily created during class redefinition.
 193   assert(num_klasses < CPKlassSlot::_temp_resolved_klass_index, "sanity");
 194   assert(resolved_klasses() == NULL, "sanity");
 195   Array<Klass*>* rk = MetadataFactory::new_array<Klass*>(loader_data, num_klasses, CHECK);
 196   set_resolved_klasses(rk);
 197 }
 198 
 199 void ConstantPool::initialize_unresolved_klasses(ClassLoaderData* loader_data, TRAPS) {
 200   int len = length();
 201   int num_klasses = 0;
 202   for (int i = 1; i <len; i++) {
 203     switch (tag_at(i).value()) {
 204     case JVM_CONSTANT_ClassIndex:
 205       {
 206         const int class_index = klass_index_at(i);
 207         unresolved_klass_at_put(i, class_index, num_klasses++);
 208       }
 209       break;
 210 #ifndef PRODUCT
 211     case JVM_CONSTANT_Class:
 212     case JVM_CONSTANT_UnresolvedClass:
 213     case JVM_CONSTANT_UnresolvedClassInError:
 214       // All of these should have been reverted back to Unresolved before calling
 215       // this function.
 216       ShouldNotReachHere();
 217 #endif
 218     }
 219   }
 220   allocate_resolved_klasses(loader_data, num_klasses, THREAD);
 221 }
 222 
 223 // Unsafe anonymous class support:
 224 void ConstantPool::klass_at_put(int class_index, int name_index, int resolved_klass_index, Klass* k, Symbol* name) {
 225   assert(is_within_bounds(class_index), "index out of bounds");
 226   assert(is_within_bounds(name_index), "index out of bounds");
 227   assert((resolved_klass_index & 0xffff0000) == 0, "must be");
 228   *int_at_addr(class_index) =
 229     build_int_from_shorts((jushort)resolved_klass_index, (jushort)name_index);
 230 
 231   symbol_at_put(name_index, name);
 232   name->increment_refcount();
 233   Klass** adr = resolved_klasses()->adr_at(resolved_klass_index);
 234   OrderAccess::release_store(adr, k);
 235 
 236   // The interpreter assumes when the tag is stored, the klass is resolved
 237   // and the Klass* non-NULL, so we need hardware store ordering here.
 238   jbyte qdesc_bit = name->is_Q_signature() ? (jbyte)JVM_CONSTANT_QDESC_BIT : 0;
 239   if (k != NULL) {
 240     release_tag_at_put(class_index, JVM_CONSTANT_Class | qdesc_bit);
 241   } else {
 242     release_tag_at_put(class_index, JVM_CONSTANT_UnresolvedClass | qdesc_bit);
 243   }
 244 }
 245 
 246 // Unsafe anonymous class support:
 247 void ConstantPool::klass_at_put(int class_index, Klass* k) {
 248   assert(k != NULL, "must be valid klass");
 249   CPKlassSlot kslot = klass_slot_at(class_index);
 250   int resolved_klass_index = kslot.resolved_klass_index();
 251   Klass** adr = resolved_klasses()->adr_at(resolved_klass_index);
 252   OrderAccess::release_store(adr, k);
 253 
 254   // The interpreter assumes when the tag is stored, the klass is resolved
 255   // and the Klass* non-NULL, so we need hardware store ordering here.

 256   release_tag_at_put(class_index, JVM_CONSTANT_Class);
 257 }
 258 
 259 #if INCLUDE_CDS_JAVA_HEAP
 260 // Archive the resolved references
 261 void ConstantPool::archive_resolved_references(Thread* THREAD) {
 262   if (_cache == NULL) {
 263     return; // nothing to do
 264   }
 265 
 266   InstanceKlass *ik = pool_holder();
 267   if (!(ik->is_shared_boot_class() || ik->is_shared_platform_class() ||
 268         ik->is_shared_app_class())) {
 269     // Archiving resolved references for classes from non-builtin loaders
 270     // is not yet supported.
 271     set_resolved_references(NULL);
 272     return;
 273   }
 274 
 275   objArrayOop rr = resolved_references();
 276   Array<u2>* ref_map = reference_map();
 277   if (rr != NULL) {
 278     int ref_map_len = ref_map == NULL ? 0 : ref_map->length();
 279     int rr_len = rr->length();
 280     for (int i = 0; i < rr_len; i++) {
 281       oop p = rr->obj_at(i);
 282       rr->obj_at_put(i, NULL);
 283       if (p != NULL && i < ref_map_len) {
 284         int index = object_to_cp_index(i);
 285         // Skip the entry if the string hash code is 0 since the string
 286         // is not included in the shared string_table, see StringTable::copy_shared_string.
 287         if (tag_at(index).is_string() && java_lang_String::hash_code(p) != 0) {
 288           oop op = StringTable::create_archived_string(p, THREAD);
 289           // If the String object is not archived (possibly too large),
 290           // NULL is returned. Also set it in the array, so we won't
 291           // have a 'bad' reference in the archived resolved_reference
 292           // array.
 293           rr->obj_at_put(i, op);
 294         }
 295       }
 296     }
 297 
 298     oop archived = HeapShared::archive_heap_object(rr, THREAD);
 299     // If the resolved references array is not archived (too large),
 300     // the 'archived' object is NULL. No need to explicitly check
 301     // the return value of archive_heap_object here. At runtime, the
 302     // resolved references will be created using the normal process
 303     // when there is no archived value.
 304     _cache->set_archived_references(archived);
 305     set_resolved_references(NULL);
 306   }
 307 }
 308 
 309 void ConstantPool::resolve_class_constants(TRAPS) {
 310   assert(DumpSharedSpaces, "used during dump time only");
 311   // The _cache may be NULL if the _pool_holder klass fails verification
 312   // at dump time due to missing dependencies.
 313   if (cache() == NULL || reference_map() == NULL) {
 314     return; // nothing to do
 315   }
 316 
 317   constantPoolHandle cp(THREAD, this);
 318   for (int index = 1; index < length(); index++) { // Index 0 is unused
 319     if (tag_at(index).is_string() && !cp->is_pseudo_string_at(index)) {
 320       int cache_index = cp->cp_to_object_index(index);
 321       string_at_impl(cp, index, cache_index, CHECK);
 322     }
 323   }
 324 }
 325 #endif
 326 
 327 // CDS support. Create a new resolved_references array.
 328 void ConstantPool::restore_unshareable_info(TRAPS) {
 329   assert(is_constantPool(), "ensure C++ vtable is restored");
 330   assert(on_stack(), "should always be set for shared constant pools");
 331   assert(is_shared(), "should always be set for shared constant pools");
 332   assert(_cache != NULL, "constant pool _cache should not be NULL");
 333 
 334   // Only create the new resolved references array if it hasn't been attempted before
 335   if (resolved_references() != NULL) return;
 336 
 337   // restore the C++ vtable from the shared archive
 338   restore_vtable();
 339 
 340   if (SystemDictionary::Object_klass_loaded()) {
 341     ClassLoaderData* loader_data = pool_holder()->class_loader_data();
 342 #if INCLUDE_CDS_JAVA_HEAP
 343     if (HeapShared::open_archive_heap_region_mapped() &&
 344         _cache->archived_references() != NULL) {
 345       oop archived = _cache->archived_references();
 346       // Create handle for the archived resolved reference array object
 347       Handle refs_handle(THREAD, archived);
 348       set_resolved_references(loader_data->add_handle(refs_handle));
 349     } else
 350 #endif
 351     {
 352       // No mapped archived resolved reference array
 353       // Recreate the object array and add to ClassLoaderData.
 354       int map_length = resolved_reference_length();
 355       if (map_length > 0) {
 356         objArrayOop stom = oopFactory::new_objArray(SystemDictionary::Object_klass(), map_length, CHECK);
 357         Handle refs_handle(THREAD, (oop)stom);  // must handleize.
 358         set_resolved_references(loader_data->add_handle(refs_handle));
 359       }
 360     }
 361   }
 362 }
 363 
 364 void ConstantPool::remove_unshareable_info() {
 365   // Resolved references are not in the shared archive.
 366   // Save the length for restoration.  It is not necessarily the same length
 367   // as reference_map.length() if invokedynamic is saved. It is needed when
 368   // re-creating the resolved reference array if archived heap data cannot be map
 369   // at runtime.
 370   set_resolved_reference_length(
 371     resolved_references() != NULL ? resolved_references()->length() : 0);
 372 
 373   // If archiving heap objects is not allowed, clear the resolved references.
 374   // Otherwise, it is cleared after the resolved references array is cached
 375   // (see archive_resolved_references()).
 376   if (!HeapShared::is_heap_object_archiving_allowed()) {
 377     set_resolved_references(NULL);
 378   }
 379 
 380   // Shared ConstantPools are in the RO region, so the _flags cannot be modified.
 381   // The _on_stack flag is used to prevent ConstantPools from deallocation during
 382   // class redefinition. Since shared ConstantPools cannot be deallocated anyway,
 383   // we always set _on_stack to true to avoid having to change _flags during runtime.
 384   _flags |= (_on_stack | _is_shared);
 385   int num_klasses = 0;
 386   for (int index = 1; index < length(); index++) { // Index 0 is unused
 387     assert(!tag_at(index).is_unresolved_klass_in_error(), "This must not happen during dump time");
 388     if (tag_at(index).is_klass()) {
 389       // This class was resolved as a side effect of executing Java code
 390       // during dump time. We need to restore it back to an UnresolvedClass,
 391       // so that the proper class loading and initialization can happen
 392       // at runtime.
 393       CPKlassSlot kslot = klass_slot_at(index);
 394       int resolved_klass_index = kslot.resolved_klass_index();
 395       int name_index = kslot.name_index();
 396       assert(tag_at(name_index).is_symbol(), "sanity");
 397       resolved_klasses()->at_put(resolved_klass_index, NULL);
 398       tag_at_put(index, JVM_CONSTANT_UnresolvedClass);
 399       assert(klass_name_at(index) == symbol_at(name_index), "sanity");
 400     }
 401   }
 402   if (cache() != NULL) {
 403     cache()->remove_unshareable_info();
 404   }
 405 }
 406 
 407 int ConstantPool::cp_to_object_index(int cp_index) {
 408   // this is harder don't do this so much.
 409   int i = reference_map()->find(cp_index);
 410   // We might not find the index for jsr292 call.
 411   return (i < 0) ? _no_index_sentinel : i;
 412 }
 413 
 414 void ConstantPool::string_at_put(int which, int obj_index, oop str) {
 415   resolved_references()->obj_at_put(obj_index, str);
 416 }
 417 
 418 void ConstantPool::trace_class_resolution(const constantPoolHandle& this_cp, Klass* k) {
 419   ResourceMark rm;
 420   int line_number = -1;
 421   const char * source_file = NULL;
 422   if (JavaThread::current()->has_last_Java_frame()) {
 423     // try to identify the method which called this function.
 424     vframeStream vfst(JavaThread::current());
 425     if (!vfst.at_end()) {
 426       line_number = vfst.method()->line_number_from_bci(vfst.bci());
 427       Symbol* s = vfst.method()->method_holder()->source_file_name();
 428       if (s != NULL) {
 429         source_file = s->as_C_string();
 430       }
 431     }
 432   }
 433   if (k != this_cp->pool_holder()) {
 434     // only print something if the classes are different
 435     if (source_file != NULL) {
 436       log_debug(class, resolve)("%s %s %s:%d",
 437                  this_cp->pool_holder()->external_name(),
 438                  k->external_name(), source_file, line_number);
 439     } else {
 440       log_debug(class, resolve)("%s %s",
 441                  this_cp->pool_holder()->external_name(),
 442                  k->external_name());
 443     }
 444   }
 445 }
 446 
 447 void check_is_value_type(Klass* k, TRAPS) {
 448   if (!k->is_value()) {
 449     THROW(vmSymbols::java_lang_IncompatibleClassChangeError());
 450   }
 451 }
 452 
 453 Klass* ConstantPool::klass_at_impl(const constantPoolHandle& this_cp, int which,
 454                                    bool save_resolution_error, TRAPS) {
 455   assert(THREAD->is_Java_thread(), "must be a Java thread");
 456   JavaThread* javaThread = (JavaThread*)THREAD;
 457 
 458   // A resolved constantPool entry will contain a Klass*, otherwise a Symbol*.
 459   // It is not safe to rely on the tag bit's here, since we don't have a lock, and
 460   // the entry and tag is not updated atomicly.
 461   CPKlassSlot kslot = this_cp->klass_slot_at(which);
 462   int resolved_klass_index = kslot.resolved_klass_index();
 463   int name_index = kslot.name_index();
 464   assert(this_cp->tag_at(name_index).is_symbol(), "sanity");
 465 
 466   Klass* klass = this_cp->resolved_klasses()->at(resolved_klass_index);
 467   if (klass != NULL) {
 468     return klass;
 469   }
 470 
 471   // This tag doesn't change back to unresolved class unless at a safepoint.
 472   if (this_cp->tag_at(which).is_unresolved_klass_in_error()) {
 473     // The original attempt to resolve this constant pool entry failed so find the
 474     // class of the original error and throw another error of the same class
 475     // (JVMS 5.4.3).
 476     // If there is a detail message, pass that detail message to the error.
 477     // The JVMS does not strictly require us to duplicate the same detail message,
 478     // or any internal exception fields such as cause or stacktrace.  But since the
 479     // detail message is often a class name or other literal string, we will repeat it
 480     // if we can find it in the symbol table.
 481     throw_resolution_error(this_cp, which, CHECK_NULL);
 482     ShouldNotReachHere();
 483   }
 484 
 485   Handle mirror_handle;
 486   Symbol* name = this_cp->symbol_at(name_index);
 487   bool value_type_signature = false;
 488   if (name->is_Q_signature()) {
 489     name = name->fundamental_name(THREAD);
 490     value_type_signature = true;
 491   }
 492   Handle loader (THREAD, this_cp->pool_holder()->class_loader());
 493   Handle protection_domain (THREAD, this_cp->pool_holder()->protection_domain());
 494 
 495   Klass* k;
 496   {
 497     // Turn off the single stepping while doing class resolution
 498     JvmtiHideSingleStepping jhss(javaThread);
 499     k = SystemDictionary::resolve_or_fail(name, loader, protection_domain, true, THREAD);
 500   } //  JvmtiHideSingleStepping jhss(javaThread);
 501   if (value_type_signature) {
 502     name->decrement_refcount();
 503   }
 504 
 505   if (!HAS_PENDING_EXCEPTION) {
 506     // preserve the resolved klass from unloading
 507     mirror_handle = Handle(THREAD, k->java_mirror());
 508     // Do access check for klasses
 509     verify_constant_pool_resolve(this_cp, k, THREAD);
 510   }
 511 
 512   if (!HAS_PENDING_EXCEPTION && value_type_signature) {
 513     check_is_value_type(k, THREAD);
 514   }
 515 
 516   if (!HAS_PENDING_EXCEPTION) {
 517     Klass* bottom_klass = NULL;
 518     if (k->is_objArray_klass()) {
 519       bottom_klass = ObjArrayKlass::cast(k)->bottom_klass();
 520       assert(bottom_klass != NULL, "Should be set");
 521       assert(bottom_klass->is_instance_klass() || bottom_klass->is_typeArray_klass(), "Sanity check");
 522     } else if (k->is_valueArray_klass()) {
 523       bottom_klass = ValueArrayKlass::cast(k)->element_klass();
 524       assert(bottom_klass != NULL, "Should be set");
 525     }
 526   }
 527 
 528   // Failed to resolve class. We must record the errors so that subsequent attempts
 529   // to resolve this constant pool entry fail with the same error (JVMS 5.4.3).
 530   if (HAS_PENDING_EXCEPTION) {
 531     if (save_resolution_error) {
 532       save_and_throw_exception(this_cp, which, constantTag(JVM_CONSTANT_UnresolvedClass), CHECK_NULL);
 533       // If CHECK_NULL above doesn't return the exception, that means that
 534       // some other thread has beaten us and has resolved the class.
 535       // To preserve old behavior, we return the resolved class.
 536       klass = this_cp->resolved_klasses()->at(resolved_klass_index);
 537       assert(klass != NULL, "must be resolved if exception was cleared");
 538       return klass;
 539     } else {
 540       return NULL;  // return the pending exception
 541     }
 542   }
 543 
 544   // logging for class+resolve.
 545   if (log_is_enabled(Debug, class, resolve)){
 546     trace_class_resolution(this_cp, k);
 547   }
 548   Klass** adr = this_cp->resolved_klasses()->adr_at(resolved_klass_index);
 549   OrderAccess::release_store(adr, k);
 550   // The interpreter assumes when the tag is stored, the klass is resolved
 551   // and the Klass* stored in _resolved_klasses is non-NULL, so we need
 552   // hardware store ordering here.
 553   jbyte tag = JVM_CONSTANT_Class;
 554   if (this_cp->tag_at(which).is_Qdescriptor_klass()) {
 555     tag |= JVM_CONSTANT_QDESC_BIT;
 556   }
 557   this_cp->release_tag_at_put(which, tag);
 558   return k;
 559 }
 560 
 561 
 562 // Does not update ConstantPool* - to avoid any exception throwing. Used
 563 // by compiler and exception handling.  Also used to avoid classloads for
 564 // instanceof operations. Returns NULL if the class has not been loaded or
 565 // if the verification of constant pool failed
 566 Klass* ConstantPool::klass_at_if_loaded(const constantPoolHandle& this_cp, int which) {
 567   CPKlassSlot kslot = this_cp->klass_slot_at(which);
 568   int resolved_klass_index = kslot.resolved_klass_index();
 569   int name_index = kslot.name_index();
 570   assert(this_cp->tag_at(name_index).is_symbol(), "sanity");
 571 
 572   Klass* k = this_cp->resolved_klasses()->at(resolved_klass_index);
 573   if (k != NULL) {
 574     return k;
 575   } else {
 576     Thread *thread = Thread::current();
 577     Symbol* name = this_cp->symbol_at(name_index);
 578     oop loader = this_cp->pool_holder()->class_loader();
 579     oop protection_domain = this_cp->pool_holder()->protection_domain();
 580     Handle h_prot (thread, protection_domain);
 581     Handle h_loader (thread, loader);
 582     Klass* k = SystemDictionary::find(name, h_loader, h_prot, thread);
 583 
 584     if (k != NULL) {
 585       // Make sure that resolving is legal
 586       EXCEPTION_MARK;
 587       // return NULL if verification fails
 588       verify_constant_pool_resolve(this_cp, k, THREAD);
 589       if (HAS_PENDING_EXCEPTION) {
 590         CLEAR_PENDING_EXCEPTION;
 591         return NULL;
 592       }
 593       return k;
 594     } else {
 595       return k;
 596     }
 597   }
 598 }
 599 
 600 Method* ConstantPool::method_at_if_loaded(const constantPoolHandle& cpool,
 601                                                    int which) {
 602   if (cpool->cache() == NULL)  return NULL;  // nothing to load yet
 603   int cache_index = decode_cpcache_index(which, true);
 604   if (!(cache_index >= 0 && cache_index < cpool->cache()->length())) {
 605     // FIXME: should be an assert
 606     log_debug(class, resolve)("bad operand %d in:", which); cpool->print();
 607     return NULL;
 608   }
 609   ConstantPoolCacheEntry* e = cpool->cache()->entry_at(cache_index);
 610   return e->method_if_resolved(cpool);
 611 }
 612 
 613 
 614 bool ConstantPool::has_appendix_at_if_loaded(const constantPoolHandle& cpool, int which) {
 615   if (cpool->cache() == NULL)  return false;  // nothing to load yet
 616   int cache_index = decode_cpcache_index(which, true);
 617   ConstantPoolCacheEntry* e = cpool->cache()->entry_at(cache_index);
 618   return e->has_appendix();
 619 }
 620 
 621 oop ConstantPool::appendix_at_if_loaded(const constantPoolHandle& cpool, int which) {
 622   if (cpool->cache() == NULL)  return NULL;  // nothing to load yet
 623   int cache_index = decode_cpcache_index(which, true);
 624   ConstantPoolCacheEntry* e = cpool->cache()->entry_at(cache_index);
 625   return e->appendix_if_resolved(cpool);
 626 }
 627 
 628 
 629 bool ConstantPool::has_local_signature_at_if_loaded(const constantPoolHandle& cpool, int which) {
 630   if (cpool->cache() == NULL)  return false;  // nothing to load yet
 631   int cache_index = decode_cpcache_index(which, true);
 632   ConstantPoolCacheEntry* e = cpool->cache()->entry_at(cache_index);
 633   return e->has_local_signature();
 634 }
 635 
 636 Symbol* ConstantPool::impl_name_ref_at(int which, bool uncached) {
 637   int name_index = name_ref_index_at(impl_name_and_type_ref_index_at(which, uncached));
 638   return symbol_at(name_index);
 639 }
 640 
 641 
 642 Symbol* ConstantPool::impl_signature_ref_at(int which, bool uncached) {
 643   int signature_index = signature_ref_index_at(impl_name_and_type_ref_index_at(which, uncached));
 644   return symbol_at(signature_index);
 645 }
 646 
 647 int ConstantPool::impl_name_and_type_ref_index_at(int which, bool uncached) {
 648   int i = which;
 649   if (!uncached && cache() != NULL) {
 650     if (ConstantPool::is_invokedynamic_index(which)) {
 651       // Invokedynamic index is index into the constant pool cache
 652       int pool_index = invokedynamic_bootstrap_ref_index_at(which);
 653       pool_index = bootstrap_name_and_type_ref_index_at(pool_index);
 654       assert(tag_at(pool_index).is_name_and_type(), "");
 655       return pool_index;
 656     }
 657     // change byte-ordering and go via cache
 658     i = remap_instruction_operand_from_cache(which);
 659   } else {
 660     if (tag_at(which).has_bootstrap()) {
 661       int pool_index = bootstrap_name_and_type_ref_index_at(which);
 662       assert(tag_at(pool_index).is_name_and_type(), "");
 663       return pool_index;
 664     }
 665   }
 666   assert(tag_at(i).is_field_or_method(), "Corrupted constant pool");
 667   assert(!tag_at(i).has_bootstrap(), "Must be handled above");
 668   jint ref_index = *int_at_addr(i);
 669   return extract_high_short_from_int(ref_index);
 670 }
 671 
 672 constantTag ConstantPool::impl_tag_ref_at(int which, bool uncached) {
 673   int pool_index = which;
 674   if (!uncached && cache() != NULL) {
 675     if (ConstantPool::is_invokedynamic_index(which)) {
 676       // Invokedynamic index is index into resolved_references
 677       pool_index = invokedynamic_bootstrap_ref_index_at(which);
 678     } else {
 679       // change byte-ordering and go via cache
 680       pool_index = remap_instruction_operand_from_cache(which);
 681     }
 682   }
 683   return tag_at(pool_index);
 684 }
 685 
 686 int ConstantPool::impl_klass_ref_index_at(int which, bool uncached) {
 687   guarantee(!ConstantPool::is_invokedynamic_index(which),
 688             "an invokedynamic instruction does not have a klass");
 689   int i = which;
 690   if (!uncached && cache() != NULL) {
 691     // change byte-ordering and go via cache
 692     i = remap_instruction_operand_from_cache(which);
 693   }
 694   assert(tag_at(i).is_field_or_method(), "Corrupted constant pool");
 695   jint ref_index = *int_at_addr(i);
 696   return extract_low_short_from_int(ref_index);
 697 }
 698 
 699 
 700 
 701 int ConstantPool::remap_instruction_operand_from_cache(int operand) {
 702   int cpc_index = operand;
 703   DEBUG_ONLY(cpc_index -= CPCACHE_INDEX_TAG);
 704   assert((int)(u2)cpc_index == cpc_index, "clean u2");
 705   int member_index = cache()->entry_at(cpc_index)->constant_pool_index();
 706   return member_index;
 707 }
 708 
 709 
 710 void ConstantPool::verify_constant_pool_resolve(const constantPoolHandle& this_cp, Klass* k, TRAPS) {
 711   if (!(k->is_instance_klass() || k->is_objArray_klass())) {
 712     return;  // short cut, typeArray klass is always accessible
 713   }
 714   Klass* holder = this_cp->pool_holder();
 715   bool fold_type_to_class = true;
 716   LinkResolver::check_klass_accessability(holder, k, fold_type_to_class, CHECK);
 717 }
 718 
 719 
 720 int ConstantPool::name_ref_index_at(int which_nt) {
 721   jint ref_index = name_and_type_at(which_nt);
 722   return extract_low_short_from_int(ref_index);
 723 }
 724 
 725 
 726 int ConstantPool::signature_ref_index_at(int which_nt) {
 727   jint ref_index = name_and_type_at(which_nt);
 728   return extract_high_short_from_int(ref_index);
 729 }
 730 
 731 
 732 Klass* ConstantPool::klass_ref_at(int which, TRAPS) {
 733   return klass_at(klass_ref_index_at(which), THREAD);
 734 }
 735 
 736 Symbol* ConstantPool::klass_name_at(int which) const {
 737   return symbol_at(klass_slot_at(which).name_index());
 738 }
 739 
 740 Symbol* ConstantPool::klass_ref_at_noresolve(int which) {
 741   jint ref_index = klass_ref_index_at(which);
 742   return klass_at_noresolve(ref_index);
 743 }
 744 
 745 Symbol* ConstantPool::uncached_klass_ref_at_noresolve(int which) {
 746   jint ref_index = uncached_klass_ref_index_at(which);
 747   return klass_at_noresolve(ref_index);
 748 }
 749 
 750 char* ConstantPool::string_at_noresolve(int which) {
 751   return unresolved_string_at(which)->as_C_string();
 752 }
 753 
 754 BasicType ConstantPool::basic_type_for_signature_at(int which) const {
 755   return FieldType::basic_type(symbol_at(which));
 756 }
 757 
 758 
 759 void ConstantPool::resolve_string_constants_impl(const constantPoolHandle& this_cp, TRAPS) {
 760   for (int index = 1; index < this_cp->length(); index++) { // Index 0 is unused
 761     if (this_cp->tag_at(index).is_string()) {
 762       this_cp->string_at(index, CHECK);
 763     }
 764   }
 765 }
 766 
 767 Symbol* ConstantPool::exception_message(const constantPoolHandle& this_cp, int which, constantTag tag, oop pending_exception) {
 768   // Dig out the detailed message to reuse if possible
 769   Symbol* message = java_lang_Throwable::detail_message(pending_exception);
 770   if (message != NULL) {
 771     return message;
 772   }
 773 
 774   // Return specific message for the tag
 775   switch (tag.value()) {
 776   case JVM_CONSTANT_UnresolvedClass:
 777     // return the class name in the error message
 778     message = this_cp->klass_name_at(which);
 779     break;
 780   case JVM_CONSTANT_MethodHandle:
 781     // return the method handle name in the error message
 782     message = this_cp->method_handle_name_ref_at(which);
 783     break;
 784   case JVM_CONSTANT_MethodType:
 785     // return the method type signature in the error message
 786     message = this_cp->method_type_signature_at(which);
 787     break;
 788   default:
 789     ShouldNotReachHere();
 790   }
 791 
 792   return message;
 793 }
 794 
 795 void ConstantPool::throw_resolution_error(const constantPoolHandle& this_cp, int which, TRAPS) {
 796   Symbol* message = NULL;
 797   Symbol* error = SystemDictionary::find_resolution_error(this_cp, which, &message);
 798   assert(error != NULL, "checking");
 799   CLEAR_PENDING_EXCEPTION;
 800   if (message != NULL) {
 801     ResourceMark rm;
 802     THROW_MSG(error, message->as_C_string());
 803   } else {
 804     THROW(error);
 805   }
 806 }
 807 
 808 // If resolution for Class, Dynamic constant, MethodHandle or MethodType fails, save the
 809 // exception in the resolution error table, so that the same exception is thrown again.
 810 void ConstantPool::save_and_throw_exception(const constantPoolHandle& this_cp, int which,
 811                                             constantTag tag, TRAPS) {
 812   Symbol* error = PENDING_EXCEPTION->klass()->name();
 813 
 814   int error_tag = tag.error_value();
 815 
 816   if (!PENDING_EXCEPTION->
 817     is_a(SystemDictionary::LinkageError_klass())) {
 818     // Just throw the exception and don't prevent these classes from
 819     // being loaded due to virtual machine errors like StackOverflow
 820     // and OutOfMemoryError, etc, or if the thread was hit by stop()
 821     // Needs clarification to section 5.4.3 of the VM spec (see 6308271)
 822   } else if (this_cp->tag_at(which).value() != error_tag) {
 823     Symbol* message = exception_message(this_cp, which, tag, PENDING_EXCEPTION);
 824     SystemDictionary::add_resolution_error(this_cp, which, error, message);
 825     // CAS in the tag.  If a thread beat us to registering this error that's fine.
 826     // If another thread resolved the reference, this is a race condition. This
 827     // thread may have had a security manager or something temporary.
 828     // This doesn't deterministically get an error.   So why do we save this?
 829     // We save this because jvmti can add classes to the bootclass path after
 830     // this error, so it needs to get the same error if the error is first.
 831     jbyte old_tag = Atomic::cmpxchg((jbyte)error_tag,
 832                             (jbyte*)this_cp->tag_addr_at(which), (jbyte)tag.value());
 833     if (old_tag != error_tag && old_tag != tag.value()) {
 834       // MethodHandles and MethodType doesn't change to resolved version.
 835       assert(this_cp->tag_at(which).is_klass(), "Wrong tag value");
 836       // Forget the exception and use the resolved class.
 837       CLEAR_PENDING_EXCEPTION;
 838     }
 839   } else {
 840     // some other thread put this in error state
 841     throw_resolution_error(this_cp, which, CHECK);
 842   }
 843 }
 844 
 845 constantTag ConstantPool::constant_tag_at(int which) {
 846   constantTag tag = tag_at(which);
 847   if (tag.is_dynamic_constant() ||
 848       tag.is_dynamic_constant_in_error()) {
 849     BasicType bt = basic_type_for_constant_at(which);
 850     // dynamic constant could return an array, treat as object
 851     return constantTag::ofBasicType(is_reference_type(bt) ? T_OBJECT : bt);
 852   }
 853   return tag;
 854 }
 855 
 856 BasicType ConstantPool::basic_type_for_constant_at(int which) {
 857   constantTag tag = tag_at(which);
 858   if (tag.is_dynamic_constant() ||
 859       tag.is_dynamic_constant_in_error()) {
 860     // have to look at the signature for this one
 861     Symbol* constant_type = uncached_signature_ref_at(which);
 862     return FieldType::basic_type(constant_type);
 863   }
 864   return tag.basic_type();
 865 }
 866 
 867 // Called to resolve constants in the constant pool and return an oop.
 868 // Some constant pool entries cache their resolved oop. This is also
 869 // called to create oops from constants to use in arguments for invokedynamic
 870 oop ConstantPool::resolve_constant_at_impl(const constantPoolHandle& this_cp,
 871                                            int index, int cache_index,
 872                                            bool* status_return, TRAPS) {
 873   oop result_oop = NULL;
 874   Handle throw_exception;
 875 
 876   if (cache_index == _possible_index_sentinel) {
 877     // It is possible that this constant is one which is cached in the objects.
 878     // We'll do a linear search.  This should be OK because this usage is rare.
 879     // FIXME: If bootstrap specifiers stress this code, consider putting in
 880     // a reverse index.  Binary search over a short array should do it.
 881     assert(index > 0, "valid index");
 882     cache_index = this_cp->cp_to_object_index(index);
 883   }
 884   assert(cache_index == _no_index_sentinel || cache_index >= 0, "");
 885   assert(index == _no_index_sentinel || index >= 0, "");
 886 
 887   if (cache_index >= 0) {
 888     result_oop = this_cp->resolved_references()->obj_at(cache_index);
 889     if (result_oop != NULL) {
 890       if (oopDesc::equals(result_oop, Universe::the_null_sentinel())) {
 891         DEBUG_ONLY(int temp_index = (index >= 0 ? index : this_cp->object_to_cp_index(cache_index)));
 892         assert(this_cp->tag_at(temp_index).is_dynamic_constant(), "only condy uses the null sentinel");
 893         result_oop = NULL;
 894       }
 895       if (status_return != NULL)  (*status_return) = true;
 896       return result_oop;
 897       // That was easy...
 898     }
 899     index = this_cp->object_to_cp_index(cache_index);
 900   }
 901 
 902   jvalue prim_value;  // temp used only in a few cases below
 903 
 904   constantTag tag = this_cp->tag_at(index);
 905 
 906   if (status_return != NULL) {
 907     // don't trigger resolution if the constant might need it
 908     switch (tag.value()) {
 909     case JVM_CONSTANT_Class:
 910     {
 911       CPKlassSlot kslot = this_cp->klass_slot_at(index);
 912       int resolved_klass_index = kslot.resolved_klass_index();
 913       if (this_cp->resolved_klasses()->at(resolved_klass_index) == NULL) {
 914         (*status_return) = false;
 915         return NULL;
 916       }
 917       // the klass is waiting in the CP; go get it
 918       break;
 919     }
 920     case JVM_CONSTANT_String:
 921     case JVM_CONSTANT_Integer:
 922     case JVM_CONSTANT_Float:
 923     case JVM_CONSTANT_Long:
 924     case JVM_CONSTANT_Double:
 925       // these guys trigger OOM at worst
 926       break;
 927     default:
 928       (*status_return) = false;
 929       return NULL;
 930     }
 931     // from now on there is either success or an OOME
 932     (*status_return) = true;
 933   }
 934 
 935   switch (tag.value()) {
 936 
 937   case JVM_CONSTANT_UnresolvedClass:
 938   case JVM_CONSTANT_UnresolvedClassInError:
 939   case JVM_CONSTANT_Class:
 940     {
 941       assert(cache_index == _no_index_sentinel, "should not have been set");
 942       Klass* resolved = klass_at_impl(this_cp, index, true, CHECK_NULL);
 943       // ldc wants the java mirror.
 944       result_oop = resolved->java_mirror();
 945       break;
 946     }
 947 
 948   case JVM_CONSTANT_Dynamic:
 949     {
 950       Klass* current_klass  = this_cp->pool_holder();
 951       Symbol* constant_name = this_cp->uncached_name_ref_at(index);
 952       Symbol* constant_type = this_cp->uncached_signature_ref_at(index);
 953 
 954       // The initial step in resolving an unresolved symbolic reference to a
 955       // dynamically-computed constant is to resolve the symbolic reference to a
 956       // method handle which will be the bootstrap method for the dynamically-computed
 957       // constant. If resolution of the java.lang.invoke.MethodHandle for the bootstrap
 958       // method fails, then a MethodHandleInError is stored at the corresponding
 959       // bootstrap method's CP index for the CONSTANT_MethodHandle_info. No need to
 960       // set a DynamicConstantInError here since any subsequent use of this
 961       // bootstrap method will encounter the resolution of MethodHandleInError.
 962       oop bsm_info = this_cp->resolve_bootstrap_specifier_at(index, THREAD);
 963       Exceptions::wrap_dynamic_exception(CHECK_NULL);
 964       assert(bsm_info != NULL, "");
 965       // FIXME: Cache this once per BootstrapMethods entry, not once per CONSTANT_Dynamic.
 966       Handle bootstrap_specifier = Handle(THREAD, bsm_info);
 967 
 968       // Resolve the Dynamically-Computed constant to invoke the BSM in order to obtain the resulting oop.
 969       Handle value = SystemDictionary::link_dynamic_constant(current_klass,
 970                                                              index,
 971                                                              bootstrap_specifier,
 972                                                              constant_name,
 973                                                              constant_type,
 974                                                              THREAD);
 975       result_oop = value();
 976       Exceptions::wrap_dynamic_exception(THREAD);
 977       if (HAS_PENDING_EXCEPTION) {
 978         // Resolution failure of the dynamically-computed constant, save_and_throw_exception
 979         // will check for a LinkageError and store a DynamicConstantInError.
 980         save_and_throw_exception(this_cp, index, tag, CHECK_NULL);
 981       }
 982       BasicType type = FieldType::basic_type(constant_type);
 983       if (!is_reference_type(type)) {
 984         // Make sure the primitive value is properly boxed.
 985         // This is a JDK responsibility.
 986         const char* fail = NULL;
 987         if (result_oop == NULL) {
 988           fail = "null result instead of box";
 989         } else if (!is_java_primitive(type)) {
 990           // FIXME: support value types via unboxing
 991           fail = "can only handle references and primitives";
 992         } else if (!java_lang_boxing_object::is_instance(result_oop, type)) {
 993           fail = "primitive is not properly boxed";
 994         }
 995         if (fail != NULL) {
 996           // Since this exception is not a LinkageError, throw exception
 997           // but do not save a DynamicInError resolution result.
 998           // See section 5.4.3 of the VM spec.
 999           THROW_MSG_NULL(vmSymbols::java_lang_InternalError(), fail);
1000         }
1001       }
1002       break;
1003     }
1004 
1005   case JVM_CONSTANT_String:
1006     assert(cache_index != _no_index_sentinel, "should have been set");
1007     if (this_cp->is_pseudo_string_at(index)) {
1008       result_oop = this_cp->pseudo_string_at(index, cache_index);
1009       break;
1010     }
1011     result_oop = string_at_impl(this_cp, index, cache_index, CHECK_NULL);
1012     break;
1013 
1014   case JVM_CONSTANT_DynamicInError:
1015   case JVM_CONSTANT_MethodHandleInError:
1016   case JVM_CONSTANT_MethodTypeInError:
1017     {
1018       throw_resolution_error(this_cp, index, CHECK_NULL);
1019       break;
1020     }
1021 
1022   case JVM_CONSTANT_MethodHandle:
1023     {
1024       int ref_kind                 = this_cp->method_handle_ref_kind_at(index);
1025       int callee_index             = this_cp->method_handle_klass_index_at(index);
1026       Symbol*  name =      this_cp->method_handle_name_ref_at(index);
1027       Symbol*  signature = this_cp->method_handle_signature_ref_at(index);
1028       constantTag m_tag  = this_cp->tag_at(this_cp->method_handle_index_at(index));
1029       { ResourceMark rm(THREAD);
1030         log_debug(class, resolve)("resolve JVM_CONSTANT_MethodHandle:%d [%d/%d/%d] %s.%s",
1031                               ref_kind, index, this_cp->method_handle_index_at(index),
1032                               callee_index, name->as_C_string(), signature->as_C_string());
1033       }
1034 
1035       Klass* callee = klass_at_impl(this_cp, callee_index, true, CHECK_NULL);
1036 
1037       // Check constant pool method consistency
1038       if ((callee->is_interface() && m_tag.is_method()) ||
1039           ((!callee->is_interface() && m_tag.is_interface_method()))) {
1040         ResourceMark rm(THREAD);
1041         char buf[400];
1042         jio_snprintf(buf, sizeof(buf),
1043           "Inconsistent constant pool data in classfile for class %s. "
1044           "Method %s%s at index %d is %s and should be %s",
1045           callee->name()->as_C_string(), name->as_C_string(), signature->as_C_string(), index,
1046           callee->is_interface() ? "CONSTANT_MethodRef" : "CONSTANT_InterfaceMethodRef",
1047           callee->is_interface() ? "CONSTANT_InterfaceMethodRef" : "CONSTANT_MethodRef");
1048         THROW_MSG_NULL(vmSymbols::java_lang_IncompatibleClassChangeError(), buf);
1049       }
1050 
1051       Klass* klass = this_cp->pool_holder();
1052       Handle value = SystemDictionary::link_method_handle_constant(klass, ref_kind,
1053                                                                    callee, name, signature,
1054                                                                    THREAD);
1055       result_oop = value();
1056       if (HAS_PENDING_EXCEPTION) {
1057         save_and_throw_exception(this_cp, index, tag, CHECK_NULL);
1058       }
1059       break;
1060     }
1061 
1062   case JVM_CONSTANT_MethodType:
1063     {
1064       Symbol*  signature = this_cp->method_type_signature_at(index);
1065       { ResourceMark rm(THREAD);
1066         log_debug(class, resolve)("resolve JVM_CONSTANT_MethodType [%d/%d] %s",
1067                               index, this_cp->method_type_index_at(index),
1068                               signature->as_C_string());
1069       }
1070       Klass* klass = this_cp->pool_holder();
1071       Handle value = SystemDictionary::find_method_handle_type(signature, klass, THREAD);
1072       result_oop = value();
1073       if (HAS_PENDING_EXCEPTION) {
1074         save_and_throw_exception(this_cp, index, tag, CHECK_NULL);
1075       }
1076       break;
1077     }
1078 
1079   case JVM_CONSTANT_Integer:
1080     assert(cache_index == _no_index_sentinel, "should not have been set");
1081     prim_value.i = this_cp->int_at(index);
1082     result_oop = java_lang_boxing_object::create(T_INT, &prim_value, CHECK_NULL);
1083     break;
1084 
1085   case JVM_CONSTANT_Float:
1086     assert(cache_index == _no_index_sentinel, "should not have been set");
1087     prim_value.f = this_cp->float_at(index);
1088     result_oop = java_lang_boxing_object::create(T_FLOAT, &prim_value, CHECK_NULL);
1089     break;
1090 
1091   case JVM_CONSTANT_Long:
1092     assert(cache_index == _no_index_sentinel, "should not have been set");
1093     prim_value.j = this_cp->long_at(index);
1094     result_oop = java_lang_boxing_object::create(T_LONG, &prim_value, CHECK_NULL);
1095     break;
1096 
1097   case JVM_CONSTANT_Double:
1098     assert(cache_index == _no_index_sentinel, "should not have been set");
1099     prim_value.d = this_cp->double_at(index);
1100     result_oop = java_lang_boxing_object::create(T_DOUBLE, &prim_value, CHECK_NULL);
1101     break;
1102 
1103   default:
1104     DEBUG_ONLY( tty->print_cr("*** %p: tag at CP[%d/%d] = %d",
1105                               this_cp(), index, cache_index, tag.value()));
1106     assert(false, "unexpected constant tag");
1107     break;
1108   }
1109 
1110   if (cache_index >= 0) {
1111     // Benign race condition:  resolved_references may already be filled in.
1112     // The important thing here is that all threads pick up the same result.
1113     // It doesn't matter which racing thread wins, as long as only one
1114     // result is used by all threads, and all future queries.
1115     oop new_result = (result_oop == NULL ? Universe::the_null_sentinel() : result_oop);
1116     oop old_result = this_cp->resolved_references()
1117       ->atomic_compare_exchange_oop(cache_index, new_result, NULL);
1118     if (old_result == NULL) {
1119       return result_oop;  // was installed
1120     } else {
1121       // Return the winning thread's result.  This can be different than
1122       // the result here for MethodHandles.
1123       if (oopDesc::equals(old_result, Universe::the_null_sentinel()))
1124         old_result = NULL;
1125       return old_result;
1126     }
1127   } else {
1128     assert(!oopDesc::equals(result_oop, Universe::the_null_sentinel()), "");
1129     return result_oop;
1130   }
1131 }
1132 
1133 oop ConstantPool::uncached_string_at(int which, TRAPS) {
1134   Symbol* sym = unresolved_string_at(which);
1135   oop str = StringTable::intern(sym, CHECK_(NULL));
1136   assert(java_lang_String::is_instance(str), "must be string");
1137   return str;
1138 }
1139 
1140 
1141 oop ConstantPool::resolve_bootstrap_specifier_at_impl(const constantPoolHandle& this_cp, int index, TRAPS) {
1142   assert((this_cp->tag_at(index).is_invoke_dynamic() ||
1143           this_cp->tag_at(index).is_dynamic_constant()), "Corrupted constant pool");
1144   Handle bsm;
1145   int argc;
1146   {
1147     // JVM_CONSTANT_InvokeDynamic is an ordered pair of [bootm, name&mtype], plus optional arguments
1148     // JVM_CONSTANT_Dynamic is an ordered pair of [bootm, name&ftype], plus optional arguments
1149     // In both cases, the bootm, being a JVM_CONSTANT_MethodHandle, has its own cache entry.
1150     // It is accompanied by the optional arguments.
1151     int bsm_index = this_cp->bootstrap_method_ref_index_at(index);
1152     oop bsm_oop = this_cp->resolve_possibly_cached_constant_at(bsm_index, CHECK_NULL);
1153     if (!java_lang_invoke_MethodHandle::is_instance(bsm_oop)) {
1154       THROW_MSG_NULL(vmSymbols::java_lang_LinkageError(), "BSM not an MethodHandle");
1155     }
1156 
1157     // Extract the optional static arguments.
1158     argc = this_cp->bootstrap_argument_count_at(index);
1159 
1160     // if there are no static arguments, return the bsm by itself:
1161     if (argc == 0 && UseBootstrapCallInfo < 2)  return bsm_oop;
1162 
1163     bsm = Handle(THREAD, bsm_oop);
1164   }
1165 
1166   // We are going to return an ordered pair of {bsm, info}, using a 2-array.
1167   objArrayHandle info;
1168   {
1169     objArrayOop info_oop = oopFactory::new_objArray(SystemDictionary::Object_klass(), 2, CHECK_NULL);
1170     info = objArrayHandle(THREAD, info_oop);
1171   }
1172 
1173   info->obj_at_put(0, bsm());
1174 
1175   bool use_BSCI;
1176   switch (UseBootstrapCallInfo) {
1177   default: use_BSCI = true;  break;  // stress mode
1178   case 0:  use_BSCI = false; break;  // stress mode
1179   case 1:                            // normal mode
1180     // If we were to support an alternative mode of BSM invocation,
1181     // we'd convert to pull mode here if the BSM could be a candidate
1182     // for that alternative mode.  We can't easily test for things
1183     // like varargs here, but we can get away with approximate testing,
1184     // since the JDK runtime will make up the difference either way.
1185     // For now, exercise the pull-mode path if the BSM is of arity 2,
1186     // or if there is a potential condy loop (see below).
1187     oop mt_oop = java_lang_invoke_MethodHandle::type(bsm());
1188     use_BSCI = (java_lang_invoke_MethodType::ptype_count(mt_oop) == 2);
1189     break;
1190   }
1191 
1192   // Here's a reason to use BSCI even if it wasn't requested:
1193   // If a condy uses a condy argument, we want to avoid infinite
1194   // recursion (condy loops) in the C code.  It's OK in Java,
1195   // because Java has stack overflow checking, so we punt
1196   // potentially cyclic cases from C to Java.
1197   if (!use_BSCI && this_cp->tag_at(index).is_dynamic_constant()) {
1198     bool found_unresolved_condy = false;
1199     for (int i = 0; i < argc; i++) {
1200       int arg_index = this_cp->bootstrap_argument_index_at(index, i);
1201       if (this_cp->tag_at(arg_index).is_dynamic_constant()) {
1202         // potential recursion point condy -> condy
1203         bool found_it = false;
1204         this_cp->find_cached_constant_at(arg_index, found_it, CHECK_NULL);
1205         if (!found_it) { found_unresolved_condy = true; break; }
1206       }
1207     }
1208     if (found_unresolved_condy)
1209       use_BSCI = true;
1210   }
1211 
1212   const int SMALL_ARITY = 5;
1213   if (use_BSCI && argc <= SMALL_ARITY && UseBootstrapCallInfo <= 2) {
1214     // If there are only a few arguments, and none of them need linking,
1215     // push them, instead of asking the JDK runtime to turn around and
1216     // pull them, saving a JVM/JDK transition in some simple cases.
1217     bool all_resolved = true;
1218     for (int i = 0; i < argc; i++) {
1219       bool found_it = false;
1220       int arg_index = this_cp->bootstrap_argument_index_at(index, i);
1221       this_cp->find_cached_constant_at(arg_index, found_it, CHECK_NULL);
1222       if (!found_it) { all_resolved = false; break; }
1223     }
1224     if (all_resolved)
1225       use_BSCI = false;
1226   }
1227 
1228   if (!use_BSCI) {
1229     // return {bsm, {arg...}}; resolution of arguments is done immediately, before JDK code is called
1230     objArrayOop args_oop = oopFactory::new_objArray(SystemDictionary::Object_klass(), argc, CHECK_NULL);
1231     info->obj_at_put(1, args_oop);   // may overwrite with args[0] below
1232     objArrayHandle args(THREAD, args_oop);
1233     copy_bootstrap_arguments_at_impl(this_cp, index, 0, argc, args, 0, true, Handle(), CHECK_NULL);
1234     if (argc == 1) {
1235       // try to discard the singleton array
1236       oop arg_oop = args->obj_at(0);
1237       if (arg_oop != NULL && !arg_oop->is_array()) {
1238         // JVM treats arrays and nulls specially in this position,
1239         // but other things are just single arguments
1240         info->obj_at_put(1, arg_oop);
1241       }
1242     }
1243   } else {
1244     // return {bsm, {arg_count, pool_index}}; JDK code must pull the arguments as needed
1245     typeArrayOop ints_oop = oopFactory::new_typeArray(T_INT, 2, CHECK_NULL);
1246     ints_oop->int_at_put(0, argc);
1247     ints_oop->int_at_put(1, index);
1248     info->obj_at_put(1, ints_oop);
1249   }
1250   return info();
1251 }
1252 
1253 void ConstantPool::copy_bootstrap_arguments_at_impl(const constantPoolHandle& this_cp, int index,
1254                                                     int start_arg, int end_arg,
1255                                                     objArrayHandle info, int pos,
1256                                                     bool must_resolve, Handle if_not_available,
1257                                                     TRAPS) {
1258   int argc;
1259   int limit = pos + end_arg - start_arg;
1260   // checks: index in range [0..this_cp->length),
1261   // tag at index, start..end in range [0..argc],
1262   // info array non-null, pos..limit in [0..info.length]
1263   if ((0 >= index    || index >= this_cp->length())  ||
1264       !(this_cp->tag_at(index).is_invoke_dynamic()    ||
1265         this_cp->tag_at(index).is_dynamic_constant()) ||
1266       (0 > start_arg || start_arg > end_arg) ||
1267       (end_arg > (argc = this_cp->bootstrap_argument_count_at(index))) ||
1268       (0 > pos       || pos > limit)         ||
1269       (info.is_null() || limit > info->length())) {
1270     // An index or something else went wrong; throw an error.
1271     // Since this is an internal API, we don't expect this,
1272     // so we don't bother to craft a nice message.
1273     THROW_MSG(vmSymbols::java_lang_LinkageError(), "bad BSM argument access");
1274   }
1275   // now we can loop safely
1276   int info_i = pos;
1277   for (int i = start_arg; i < end_arg; i++) {
1278     int arg_index = this_cp->bootstrap_argument_index_at(index, i);
1279     oop arg_oop;
1280     if (must_resolve) {
1281       arg_oop = this_cp->resolve_possibly_cached_constant_at(arg_index, CHECK);
1282     } else {
1283       bool found_it = false;
1284       arg_oop = this_cp->find_cached_constant_at(arg_index, found_it, CHECK);
1285       if (!found_it)  arg_oop = if_not_available();
1286     }
1287     info->obj_at_put(info_i++, arg_oop);
1288   }
1289 }
1290 
1291 oop ConstantPool::string_at_impl(const constantPoolHandle& this_cp, int which, int obj_index, TRAPS) {
1292   // If the string has already been interned, this entry will be non-null
1293   oop str = this_cp->resolved_references()->obj_at(obj_index);
1294   assert(!oopDesc::equals(str, Universe::the_null_sentinel()), "");
1295   if (str != NULL) return str;
1296   Symbol* sym = this_cp->unresolved_string_at(which);
1297   str = StringTable::intern(sym, CHECK_(NULL));
1298   this_cp->string_at_put(which, obj_index, str);
1299   assert(java_lang_String::is_instance(str), "must be string");
1300   return str;
1301 }
1302 
1303 
1304 bool ConstantPool::klass_name_at_matches(const InstanceKlass* k, int which) {
1305   // Names are interned, so we can compare Symbol*s directly
1306   Symbol* cp_name = klass_name_at(which);
1307   return (cp_name == k->name());
1308 }
1309 
1310 
1311 // Iterate over symbols and decrement ones which are Symbol*s
1312 // This is done during GC.
1313 // Only decrement the UTF8 symbols. Strings point to
1314 // these symbols but didn't increment the reference count.
1315 void ConstantPool::unreference_symbols() {
1316   for (int index = 1; index < length(); index++) { // Index 0 is unused
1317     constantTag tag = tag_at(index);
1318     if (tag.is_symbol()) {
1319       symbol_at(index)->decrement_refcount();
1320     }
1321   }
1322 }
1323 
1324 
1325 // Compare this constant pool's entry at index1 to the constant pool
1326 // cp2's entry at index2.
1327 bool ConstantPool::compare_entry_to(int index1, const constantPoolHandle& cp2,
1328        int index2, TRAPS) {
1329 
1330   // The error tags are equivalent to non-error tags when comparing
1331   jbyte t1 = tag_at(index1).non_error_value();
1332   jbyte t2 = cp2->tag_at(index2).non_error_value();
1333 
1334   if (t1 != t2) {
1335     // Not the same entry type so there is nothing else to check. Note
1336     // that this style of checking will consider resolved/unresolved
1337     // class pairs as different.
1338     // From the ConstantPool* API point of view, this is correct
1339     // behavior. See VM_RedefineClasses::merge_constant_pools() to see how this
1340     // plays out in the context of ConstantPool* merging.
1341     return false;
1342   }
1343 
1344   switch (t1) {
1345   case JVM_CONSTANT_Class:
1346   {
1347     Klass* k1 = klass_at(index1, CHECK_false);
1348     Klass* k2 = cp2->klass_at(index2, CHECK_false);
1349     if (k1 == k2) {
1350       return true;
1351     }
1352   } break;
1353 
1354   case JVM_CONSTANT_ClassIndex:
1355   {
1356     int recur1 = klass_index_at(index1);
1357     int recur2 = cp2->klass_index_at(index2);
1358     bool match = compare_entry_to(recur1, cp2, recur2, CHECK_false);
1359     if (match) {
1360       return true;
1361     }
1362   } break;
1363 
1364   case JVM_CONSTANT_Double:
1365   {
1366     jdouble d1 = double_at(index1);
1367     jdouble d2 = cp2->double_at(index2);
1368     if (d1 == d2) {
1369       return true;
1370     }
1371   } break;
1372 
1373   case JVM_CONSTANT_Fieldref:
1374   case JVM_CONSTANT_InterfaceMethodref:
1375   case JVM_CONSTANT_Methodref:
1376   {
1377     int recur1 = uncached_klass_ref_index_at(index1);
1378     int recur2 = cp2->uncached_klass_ref_index_at(index2);
1379     bool match = compare_entry_to(recur1, cp2, recur2, CHECK_false);
1380     if (match) {
1381       recur1 = uncached_name_and_type_ref_index_at(index1);
1382       recur2 = cp2->uncached_name_and_type_ref_index_at(index2);
1383       match = compare_entry_to(recur1, cp2, recur2, CHECK_false);
1384       if (match) {
1385         return true;
1386       }
1387     }
1388   } break;
1389 
1390   case JVM_CONSTANT_Float:
1391   {
1392     jfloat f1 = float_at(index1);
1393     jfloat f2 = cp2->float_at(index2);
1394     if (f1 == f2) {
1395       return true;
1396     }
1397   } break;
1398 
1399   case JVM_CONSTANT_Integer:
1400   {
1401     jint i1 = int_at(index1);
1402     jint i2 = cp2->int_at(index2);
1403     if (i1 == i2) {
1404       return true;
1405     }
1406   } break;
1407 
1408   case JVM_CONSTANT_Long:
1409   {
1410     jlong l1 = long_at(index1);
1411     jlong l2 = cp2->long_at(index2);
1412     if (l1 == l2) {
1413       return true;
1414     }
1415   } break;
1416 
1417   case JVM_CONSTANT_NameAndType:
1418   {
1419     int recur1 = name_ref_index_at(index1);
1420     int recur2 = cp2->name_ref_index_at(index2);
1421     bool match = compare_entry_to(recur1, cp2, recur2, CHECK_false);
1422     if (match) {
1423       recur1 = signature_ref_index_at(index1);
1424       recur2 = cp2->signature_ref_index_at(index2);
1425       match = compare_entry_to(recur1, cp2, recur2, CHECK_false);
1426       if (match) {
1427         return true;
1428       }
1429     }
1430   } break;
1431 
1432   case JVM_CONSTANT_StringIndex:
1433   {
1434     int recur1 = string_index_at(index1);
1435     int recur2 = cp2->string_index_at(index2);
1436     bool match = compare_entry_to(recur1, cp2, recur2, CHECK_false);
1437     if (match) {
1438       return true;
1439     }
1440   } break;
1441 
1442   case JVM_CONSTANT_UnresolvedClass:
1443   {
1444     Symbol* k1 = klass_name_at(index1);
1445     Symbol* k2 = cp2->klass_name_at(index2);
1446     if (k1 == k2) {
1447       return true;
1448     }
1449   } break;
1450 
1451   case JVM_CONSTANT_MethodType:
1452   {
1453     int k1 = method_type_index_at(index1);
1454     int k2 = cp2->method_type_index_at(index2);
1455     bool match = compare_entry_to(k1, cp2, k2, CHECK_false);
1456     if (match) {
1457       return true;
1458     }
1459   } break;
1460 
1461   case JVM_CONSTANT_MethodHandle:
1462   {
1463     int k1 = method_handle_ref_kind_at(index1);
1464     int k2 = cp2->method_handle_ref_kind_at(index2);
1465     if (k1 == k2) {
1466       int i1 = method_handle_index_at(index1);
1467       int i2 = cp2->method_handle_index_at(index2);
1468       bool match = compare_entry_to(i1, cp2, i2, CHECK_false);
1469       if (match) {
1470         return true;
1471       }
1472     }
1473   } break;
1474 
1475   case JVM_CONSTANT_Dynamic:
1476   {
1477     int k1 = bootstrap_name_and_type_ref_index_at(index1);
1478     int k2 = cp2->bootstrap_name_and_type_ref_index_at(index2);
1479     int i1 = bootstrap_methods_attribute_index(index1);
1480     int i2 = cp2->bootstrap_methods_attribute_index(index2);
1481     // separate statements and variables because CHECK_false is used
1482     bool match_entry = compare_entry_to(k1, cp2, k2, CHECK_false);
1483     bool match_operand = compare_operand_to(i1, cp2, i2, CHECK_false);
1484     return (match_entry && match_operand);
1485   } break;
1486 
1487   case JVM_CONSTANT_InvokeDynamic:
1488   {
1489     int k1 = bootstrap_name_and_type_ref_index_at(index1);
1490     int k2 = cp2->bootstrap_name_and_type_ref_index_at(index2);
1491     int i1 = bootstrap_methods_attribute_index(index1);
1492     int i2 = cp2->bootstrap_methods_attribute_index(index2);
1493     // separate statements and variables because CHECK_false is used
1494     bool match_entry = compare_entry_to(k1, cp2, k2, CHECK_false);
1495     bool match_operand = compare_operand_to(i1, cp2, i2, CHECK_false);
1496     return (match_entry && match_operand);
1497   } break;
1498 
1499   case JVM_CONSTANT_String:
1500   {
1501     Symbol* s1 = unresolved_string_at(index1);
1502     Symbol* s2 = cp2->unresolved_string_at(index2);
1503     if (s1 == s2) {
1504       return true;
1505     }
1506   } break;
1507 
1508   case JVM_CONSTANT_Utf8:
1509   {
1510     Symbol* s1 = symbol_at(index1);
1511     Symbol* s2 = cp2->symbol_at(index2);
1512     if (s1 == s2) {
1513       return true;
1514     }
1515   } break;
1516 
1517   // Invalid is used as the tag for the second constant pool entry
1518   // occupied by JVM_CONSTANT_Double or JVM_CONSTANT_Long. It should
1519   // not be seen by itself.
1520   case JVM_CONSTANT_Invalid: // fall through
1521 
1522   default:
1523     ShouldNotReachHere();
1524     break;
1525   }
1526 
1527   return false;
1528 } // end compare_entry_to()
1529 
1530 
1531 // Resize the operands array with delta_len and delta_size.
1532 // Used in RedefineClasses for CP merge.
1533 void ConstantPool::resize_operands(int delta_len, int delta_size, TRAPS) {
1534   int old_len  = operand_array_length(operands());
1535   int new_len  = old_len + delta_len;
1536   int min_len  = (delta_len > 0) ? old_len : new_len;
1537 
1538   int old_size = operands()->length();
1539   int new_size = old_size + delta_size;
1540   int min_size = (delta_size > 0) ? old_size : new_size;
1541 
1542   ClassLoaderData* loader_data = pool_holder()->class_loader_data();
1543   Array<u2>* new_ops = MetadataFactory::new_array<u2>(loader_data, new_size, CHECK);
1544 
1545   // Set index in the resized array for existing elements only
1546   for (int idx = 0; idx < min_len; idx++) {
1547     int offset = operand_offset_at(idx);                       // offset in original array
1548     operand_offset_at_put(new_ops, idx, offset + 2*delta_len); // offset in resized array
1549   }
1550   // Copy the bootstrap specifiers only
1551   Copy::conjoint_memory_atomic(operands()->adr_at(2*old_len),
1552                                new_ops->adr_at(2*new_len),
1553                                (min_size - 2*min_len) * sizeof(u2));
1554   // Explicitly deallocate old operands array.
1555   // Note, it is not needed for 7u backport.
1556   if ( operands() != NULL) { // the safety check
1557     MetadataFactory::free_array<u2>(loader_data, operands());
1558   }
1559   set_operands(new_ops);
1560 } // end resize_operands()
1561 
1562 
1563 // Extend the operands array with the length and size of the ext_cp operands.
1564 // Used in RedefineClasses for CP merge.
1565 void ConstantPool::extend_operands(const constantPoolHandle& ext_cp, TRAPS) {
1566   int delta_len = operand_array_length(ext_cp->operands());
1567   if (delta_len == 0) {
1568     return; // nothing to do
1569   }
1570   int delta_size = ext_cp->operands()->length();
1571 
1572   assert(delta_len  > 0 && delta_size > 0, "extended operands array must be bigger");
1573 
1574   if (operand_array_length(operands()) == 0) {
1575     ClassLoaderData* loader_data = pool_holder()->class_loader_data();
1576     Array<u2>* new_ops = MetadataFactory::new_array<u2>(loader_data, delta_size, CHECK);
1577     // The first element index defines the offset of second part
1578     operand_offset_at_put(new_ops, 0, 2*delta_len); // offset in new array
1579     set_operands(new_ops);
1580   } else {
1581     resize_operands(delta_len, delta_size, CHECK);
1582   }
1583 
1584 } // end extend_operands()
1585 
1586 
1587 // Shrink the operands array to a smaller array with new_len length.
1588 // Used in RedefineClasses for CP merge.
1589 void ConstantPool::shrink_operands(int new_len, TRAPS) {
1590   int old_len = operand_array_length(operands());
1591   if (new_len == old_len) {
1592     return; // nothing to do
1593   }
1594   assert(new_len < old_len, "shrunken operands array must be smaller");
1595 
1596   int free_base  = operand_next_offset_at(new_len - 1);
1597   int delta_len  = new_len - old_len;
1598   int delta_size = 2*delta_len + free_base - operands()->length();
1599 
1600   resize_operands(delta_len, delta_size, CHECK);
1601 
1602 } // end shrink_operands()
1603 
1604 
1605 void ConstantPool::copy_operands(const constantPoolHandle& from_cp,
1606                                  const constantPoolHandle& to_cp,
1607                                  TRAPS) {
1608 
1609   int from_oplen = operand_array_length(from_cp->operands());
1610   int old_oplen  = operand_array_length(to_cp->operands());
1611   if (from_oplen != 0) {
1612     ClassLoaderData* loader_data = to_cp->pool_holder()->class_loader_data();
1613     // append my operands to the target's operands array
1614     if (old_oplen == 0) {
1615       // Can't just reuse from_cp's operand list because of deallocation issues
1616       int len = from_cp->operands()->length();
1617       Array<u2>* new_ops = MetadataFactory::new_array<u2>(loader_data, len, CHECK);
1618       Copy::conjoint_memory_atomic(
1619           from_cp->operands()->adr_at(0), new_ops->adr_at(0), len * sizeof(u2));
1620       to_cp->set_operands(new_ops);
1621     } else {
1622       int old_len  = to_cp->operands()->length();
1623       int from_len = from_cp->operands()->length();
1624       int old_off  = old_oplen * sizeof(u2);
1625       int from_off = from_oplen * sizeof(u2);
1626       // Use the metaspace for the destination constant pool
1627       Array<u2>* new_operands = MetadataFactory::new_array<u2>(loader_data, old_len + from_len, CHECK);
1628       int fillp = 0, len = 0;
1629       // first part of dest
1630       Copy::conjoint_memory_atomic(to_cp->operands()->adr_at(0),
1631                                    new_operands->adr_at(fillp),
1632                                    (len = old_off) * sizeof(u2));
1633       fillp += len;
1634       // first part of src
1635       Copy::conjoint_memory_atomic(from_cp->operands()->adr_at(0),
1636                                    new_operands->adr_at(fillp),
1637                                    (len = from_off) * sizeof(u2));
1638       fillp += len;
1639       // second part of dest
1640       Copy::conjoint_memory_atomic(to_cp->operands()->adr_at(old_off),
1641                                    new_operands->adr_at(fillp),
1642                                    (len = old_len - old_off) * sizeof(u2));
1643       fillp += len;
1644       // second part of src
1645       Copy::conjoint_memory_atomic(from_cp->operands()->adr_at(from_off),
1646                                    new_operands->adr_at(fillp),
1647                                    (len = from_len - from_off) * sizeof(u2));
1648       fillp += len;
1649       assert(fillp == new_operands->length(), "");
1650 
1651       // Adjust indexes in the first part of the copied operands array.
1652       for (int j = 0; j < from_oplen; j++) {
1653         int offset = operand_offset_at(new_operands, old_oplen + j);
1654         assert(offset == operand_offset_at(from_cp->operands(), j), "correct copy");
1655         offset += old_len;  // every new tuple is preceded by old_len extra u2's
1656         operand_offset_at_put(new_operands, old_oplen + j, offset);
1657       }
1658 
1659       // replace target operands array with combined array
1660       to_cp->set_operands(new_operands);
1661     }
1662   }
1663 } // end copy_operands()
1664 
1665 
1666 // Copy this constant pool's entries at start_i to end_i (inclusive)
1667 // to the constant pool to_cp's entries starting at to_i. A total of
1668 // (end_i - start_i) + 1 entries are copied.
1669 void ConstantPool::copy_cp_to_impl(const constantPoolHandle& from_cp, int start_i, int end_i,
1670        const constantPoolHandle& to_cp, int to_i, TRAPS) {
1671 
1672 
1673   int dest_i = to_i;  // leave original alone for debug purposes
1674 
1675   for (int src_i = start_i; src_i <= end_i; /* see loop bottom */ ) {
1676     copy_entry_to(from_cp, src_i, to_cp, dest_i, CHECK);
1677 
1678     switch (from_cp->tag_at(src_i).value()) {
1679     case JVM_CONSTANT_Double:
1680     case JVM_CONSTANT_Long:
1681       // double and long take two constant pool entries
1682       src_i += 2;
1683       dest_i += 2;
1684       break;
1685 
1686     default:
1687       // all others take one constant pool entry
1688       src_i++;
1689       dest_i++;
1690       break;
1691     }
1692   }
1693   copy_operands(from_cp, to_cp, CHECK);
1694 
1695 } // end copy_cp_to_impl()
1696 
1697 
1698 // Copy this constant pool's entry at from_i to the constant pool
1699 // to_cp's entry at to_i.
1700 void ConstantPool::copy_entry_to(const constantPoolHandle& from_cp, int from_i,
1701                                         const constantPoolHandle& to_cp, int to_i,
1702                                         TRAPS) {
1703 
1704   int tag = from_cp->tag_at(from_i).value();
1705   switch (tag) {
1706   case JVM_CONSTANT_ClassIndex:
1707   {
1708     jint ki = from_cp->klass_index_at(from_i);
1709     to_cp->klass_index_at_put(to_i, ki);
1710   } break;
1711 
1712   case JVM_CONSTANT_Double:
1713   {
1714     jdouble d = from_cp->double_at(from_i);
1715     to_cp->double_at_put(to_i, d);
1716     // double takes two constant pool entries so init second entry's tag
1717     to_cp->tag_at_put(to_i + 1, JVM_CONSTANT_Invalid);
1718   } break;
1719 
1720   case JVM_CONSTANT_Fieldref:
1721   {
1722     int class_index = from_cp->uncached_klass_ref_index_at(from_i);
1723     int name_and_type_index = from_cp->uncached_name_and_type_ref_index_at(from_i);
1724     to_cp->field_at_put(to_i, class_index, name_and_type_index);
1725   } break;
1726 
1727   case JVM_CONSTANT_Float:
1728   {
1729     jfloat f = from_cp->float_at(from_i);
1730     to_cp->float_at_put(to_i, f);
1731   } break;
1732 
1733   case JVM_CONSTANT_Integer:
1734   {
1735     jint i = from_cp->int_at(from_i);
1736     to_cp->int_at_put(to_i, i);
1737   } break;
1738 
1739   case JVM_CONSTANT_InterfaceMethodref:
1740   {
1741     int class_index = from_cp->uncached_klass_ref_index_at(from_i);
1742     int name_and_type_index = from_cp->uncached_name_and_type_ref_index_at(from_i);
1743     to_cp->interface_method_at_put(to_i, class_index, name_and_type_index);
1744   } break;
1745 
1746   case JVM_CONSTANT_Long:
1747   {
1748     jlong l = from_cp->long_at(from_i);
1749     to_cp->long_at_put(to_i, l);
1750     // long takes two constant pool entries so init second entry's tag
1751     to_cp->tag_at_put(to_i + 1, JVM_CONSTANT_Invalid);
1752   } break;
1753 
1754   case JVM_CONSTANT_Methodref:
1755   {
1756     int class_index = from_cp->uncached_klass_ref_index_at(from_i);
1757     int name_and_type_index = from_cp->uncached_name_and_type_ref_index_at(from_i);
1758     to_cp->method_at_put(to_i, class_index, name_and_type_index);
1759   } break;
1760 
1761   case JVM_CONSTANT_NameAndType:
1762   {
1763     int name_ref_index = from_cp->name_ref_index_at(from_i);
1764     int signature_ref_index = from_cp->signature_ref_index_at(from_i);
1765     to_cp->name_and_type_at_put(to_i, name_ref_index, signature_ref_index);
1766   } break;
1767 
1768   case JVM_CONSTANT_StringIndex:
1769   {
1770     jint si = from_cp->string_index_at(from_i);
1771     to_cp->string_index_at_put(to_i, si);
1772   } break;
1773 
1774   case JVM_CONSTANT_Class:
1775   case JVM_CONSTANT_UnresolvedClass:
1776   case JVM_CONSTANT_UnresolvedClassInError:
1777   {
1778     // Revert to JVM_CONSTANT_ClassIndex
1779     int name_index = from_cp->klass_slot_at(from_i).name_index();
1780     assert(from_cp->tag_at(name_index).is_symbol(), "sanity");
1781     to_cp->klass_index_at_put(to_i, name_index);
1782   } break;
1783 
1784   case JVM_CONSTANT_String:
1785   {
1786     Symbol* s = from_cp->unresolved_string_at(from_i);
1787     to_cp->unresolved_string_at_put(to_i, s);
1788   } break;
1789 
1790   case JVM_CONSTANT_Utf8:
1791   {
1792     Symbol* s = from_cp->symbol_at(from_i);
1793     // Need to increase refcount, the old one will be thrown away and deferenced
1794     s->increment_refcount();
1795     to_cp->symbol_at_put(to_i, s);
1796   } break;
1797 
1798   case JVM_CONSTANT_MethodType:
1799   case JVM_CONSTANT_MethodTypeInError:
1800   {
1801     jint k = from_cp->method_type_index_at(from_i);
1802     to_cp->method_type_index_at_put(to_i, k);
1803   } break;
1804 
1805   case JVM_CONSTANT_MethodHandle:
1806   case JVM_CONSTANT_MethodHandleInError:
1807   {
1808     int k1 = from_cp->method_handle_ref_kind_at(from_i);
1809     int k2 = from_cp->method_handle_index_at(from_i);
1810     to_cp->method_handle_index_at_put(to_i, k1, k2);
1811   } break;
1812 
1813   case JVM_CONSTANT_Dynamic:
1814   case JVM_CONSTANT_DynamicInError:
1815   {
1816     int k1 = from_cp->bootstrap_methods_attribute_index(from_i);
1817     int k2 = from_cp->bootstrap_name_and_type_ref_index_at(from_i);
1818     k1 += operand_array_length(to_cp->operands());  // to_cp might already have operands
1819     to_cp->dynamic_constant_at_put(to_i, k1, k2);
1820   } break;
1821 
1822   case JVM_CONSTANT_InvokeDynamic:
1823   {
1824     int k1 = from_cp->bootstrap_methods_attribute_index(from_i);
1825     int k2 = from_cp->bootstrap_name_and_type_ref_index_at(from_i);
1826     k1 += operand_array_length(to_cp->operands());  // to_cp might already have operands
1827     to_cp->invoke_dynamic_at_put(to_i, k1, k2);
1828   } break;
1829 
1830   // Invalid is used as the tag for the second constant pool entry
1831   // occupied by JVM_CONSTANT_Double or JVM_CONSTANT_Long. It should
1832   // not be seen by itself.
1833   case JVM_CONSTANT_Invalid: // fall through
1834 
1835   default:
1836   {
1837     ShouldNotReachHere();
1838   } break;
1839   }
1840 } // end copy_entry_to()
1841 
1842 // Search constant pool search_cp for an entry that matches this
1843 // constant pool's entry at pattern_i. Returns the index of a
1844 // matching entry or zero (0) if there is no matching entry.
1845 int ConstantPool::find_matching_entry(int pattern_i,
1846       const constantPoolHandle& search_cp, TRAPS) {
1847 
1848   // index zero (0) is not used
1849   for (int i = 1; i < search_cp->length(); i++) {
1850     bool found = compare_entry_to(pattern_i, search_cp, i, CHECK_0);
1851     if (found) {
1852       return i;
1853     }
1854   }
1855 
1856   return 0;  // entry not found; return unused index zero (0)
1857 } // end find_matching_entry()
1858 
1859 
1860 // Compare this constant pool's bootstrap specifier at idx1 to the constant pool
1861 // cp2's bootstrap specifier at idx2.
1862 bool ConstantPool::compare_operand_to(int idx1, const constantPoolHandle& cp2, int idx2, TRAPS) {
1863   int k1 = operand_bootstrap_method_ref_index_at(idx1);
1864   int k2 = cp2->operand_bootstrap_method_ref_index_at(idx2);
1865   bool match = compare_entry_to(k1, cp2, k2, CHECK_false);
1866 
1867   if (!match) {
1868     return false;
1869   }
1870   int argc = operand_argument_count_at(idx1);
1871   if (argc == cp2->operand_argument_count_at(idx2)) {
1872     for (int j = 0; j < argc; j++) {
1873       k1 = operand_argument_index_at(idx1, j);
1874       k2 = cp2->operand_argument_index_at(idx2, j);
1875       match = compare_entry_to(k1, cp2, k2, CHECK_false);
1876       if (!match) {
1877         return false;
1878       }
1879     }
1880     return true;           // got through loop; all elements equal
1881   }
1882   return false;
1883 } // end compare_operand_to()
1884 
1885 // Search constant pool search_cp for a bootstrap specifier that matches
1886 // this constant pool's bootstrap specifier at pattern_i index.
1887 // Return the index of a matching bootstrap specifier or (-1) if there is no match.
1888 int ConstantPool::find_matching_operand(int pattern_i,
1889                     const constantPoolHandle& search_cp, int search_len, TRAPS) {
1890   for (int i = 0; i < search_len; i++) {
1891     bool found = compare_operand_to(pattern_i, search_cp, i, CHECK_(-1));
1892     if (found) {
1893       return i;
1894     }
1895   }
1896   return -1;  // bootstrap specifier not found; return unused index (-1)
1897 } // end find_matching_operand()
1898 
1899 
1900 #ifndef PRODUCT
1901 
1902 const char* ConstantPool::printable_name_at(int which) {
1903 
1904   constantTag tag = tag_at(which);
1905 
1906   if (tag.is_string()) {
1907     return string_at_noresolve(which);
1908   } else if (tag.is_klass() || tag.is_unresolved_klass()) {
1909     return klass_name_at(which)->as_C_string();
1910   } else if (tag.is_symbol()) {
1911     return symbol_at(which)->as_C_string();
1912   }
1913   return "";
1914 }
1915 
1916 #endif // PRODUCT
1917 
1918 
1919 // JVMTI GetConstantPool support
1920 
1921 // For debugging of constant pool
1922 const bool debug_cpool = false;
1923 
1924 #define DBG(code) do { if (debug_cpool) { (code); } } while(0)
1925 
1926 static void print_cpool_bytes(jint cnt, u1 *bytes) {
1927   const char* WARN_MSG = "Must not be such entry!";
1928   jint size = 0;
1929   u2   idx1, idx2;
1930 
1931   for (jint idx = 1; idx < cnt; idx++) {
1932     jint ent_size = 0;
1933     u1   tag  = *bytes++;
1934     size++;                       // count tag
1935 
1936     printf("const #%03d, tag: %02d ", idx, tag);
1937     switch(tag) {
1938       case JVM_CONSTANT_Invalid: {
1939         printf("Invalid");
1940         break;
1941       }
1942       case JVM_CONSTANT_Unicode: {
1943         printf("Unicode      %s", WARN_MSG);
1944         break;
1945       }
1946       case JVM_CONSTANT_Utf8: {
1947         u2 len = Bytes::get_Java_u2(bytes);
1948         char str[128];
1949         if (len > 127) {
1950            len = 127;
1951         }
1952         strncpy(str, (char *) (bytes+2), len);
1953         str[len] = '\0';
1954         printf("Utf8          \"%s\"", str);
1955         ent_size = 2 + len;
1956         break;
1957       }
1958       case JVM_CONSTANT_Integer: {
1959         u4 val = Bytes::get_Java_u4(bytes);
1960         printf("int          %d", *(int *) &val);
1961         ent_size = 4;
1962         break;
1963       }
1964       case JVM_CONSTANT_Float: {
1965         u4 val = Bytes::get_Java_u4(bytes);
1966         printf("float        %5.3ff", *(float *) &val);
1967         ent_size = 4;
1968         break;
1969       }
1970       case JVM_CONSTANT_Long: {
1971         u8 val = Bytes::get_Java_u8(bytes);
1972         printf("long         " INT64_FORMAT, (int64_t) *(jlong *) &val);
1973         ent_size = 8;
1974         idx++; // Long takes two cpool slots
1975         break;
1976       }
1977       case JVM_CONSTANT_Double: {
1978         u8 val = Bytes::get_Java_u8(bytes);
1979         printf("double       %5.3fd", *(jdouble *)&val);
1980         ent_size = 8;
1981         idx++; // Double takes two cpool slots
1982         break;
1983       }
1984       case JVM_CONSTANT_Class: {
1985         idx1 = Bytes::get_Java_u2(bytes);
1986         printf("class        #%03d", idx1);
1987         ent_size = 2;
1988         break;
1989       }






1990       case JVM_CONSTANT_String: {
1991         idx1 = Bytes::get_Java_u2(bytes);
1992         printf("String       #%03d", idx1);
1993         ent_size = 2;
1994         break;
1995       }
1996       case JVM_CONSTANT_Fieldref: {
1997         idx1 = Bytes::get_Java_u2(bytes);
1998         idx2 = Bytes::get_Java_u2(bytes+2);
1999         printf("Field        #%03d, #%03d", (int) idx1, (int) idx2);
2000         ent_size = 4;
2001         break;
2002       }
2003       case JVM_CONSTANT_Methodref: {
2004         idx1 = Bytes::get_Java_u2(bytes);
2005         idx2 = Bytes::get_Java_u2(bytes+2);
2006         printf("Method       #%03d, #%03d", idx1, idx2);
2007         ent_size = 4;
2008         break;
2009       }
2010       case JVM_CONSTANT_InterfaceMethodref: {
2011         idx1 = Bytes::get_Java_u2(bytes);
2012         idx2 = Bytes::get_Java_u2(bytes+2);
2013         printf("InterfMethod #%03d, #%03d", idx1, idx2);
2014         ent_size = 4;
2015         break;
2016       }
2017       case JVM_CONSTANT_NameAndType: {
2018         idx1 = Bytes::get_Java_u2(bytes);
2019         idx2 = Bytes::get_Java_u2(bytes+2);
2020         printf("NameAndType  #%03d, #%03d", idx1, idx2);
2021         ent_size = 4;
2022         break;
2023       }
2024       case JVM_CONSTANT_ClassIndex: {
2025         printf("ClassIndex  %s", WARN_MSG);
2026         break;
2027       }
2028       case JVM_CONSTANT_UnresolvedClass: {
2029         printf("UnresolvedClass: %s", WARN_MSG);
2030         break;
2031       }




2032       case JVM_CONSTANT_UnresolvedClassInError: {
2033         printf("UnresolvedClassInErr: %s", WARN_MSG);
2034         break;
2035       }
2036       case JVM_CONSTANT_StringIndex: {
2037         printf("StringIndex: %s", WARN_MSG);
2038         break;
2039       }
2040     }
2041     printf(";\n");
2042     bytes += ent_size;
2043     size  += ent_size;
2044   }
2045   printf("Cpool size: %d\n", size);
2046   fflush(0);
2047   return;
2048 } /* end print_cpool_bytes */
2049 
2050 
2051 // Returns size of constant pool entry.
2052 jint ConstantPool::cpool_entry_size(jint idx) {
2053   switch(tag_at(idx).value()) {
2054     case JVM_CONSTANT_Invalid:
2055     case JVM_CONSTANT_Unicode:
2056       return 1;
2057 
2058     case JVM_CONSTANT_Utf8:
2059       return 3 + symbol_at(idx)->utf8_length();
2060 
2061     case JVM_CONSTANT_Class:
2062     case JVM_CONSTANT_String:
2063     case JVM_CONSTANT_ClassIndex:
2064     case JVM_CONSTANT_UnresolvedClass:
2065     case JVM_CONSTANT_UnresolvedClassInError:
2066     case JVM_CONSTANT_StringIndex:
2067     case JVM_CONSTANT_MethodType:
2068     case JVM_CONSTANT_MethodTypeInError:
2069       return 3;
2070 
2071     case JVM_CONSTANT_MethodHandle:
2072     case JVM_CONSTANT_MethodHandleInError:
2073       return 4; //tag, ref_kind, ref_index
2074 
2075     case JVM_CONSTANT_Integer:
2076     case JVM_CONSTANT_Float:
2077     case JVM_CONSTANT_Fieldref:
2078     case JVM_CONSTANT_Methodref:
2079     case JVM_CONSTANT_InterfaceMethodref:
2080     case JVM_CONSTANT_NameAndType:
2081       return 5;
2082 
2083     case JVM_CONSTANT_Dynamic:
2084     case JVM_CONSTANT_DynamicInError:
2085     case JVM_CONSTANT_InvokeDynamic:
2086       // u1 tag, u2 bsm, u2 nt
2087       return 5;
2088 
2089     case JVM_CONSTANT_Long:
2090     case JVM_CONSTANT_Double:
2091       return 9;
2092   }
2093   assert(false, "cpool_entry_size: Invalid constant pool entry tag");
2094   return 1;
2095 } /* end cpool_entry_size */
2096 
2097 
2098 // SymbolHashMap is used to find a constant pool index from a string.
2099 // This function fills in SymbolHashMaps, one for utf8s and one for
2100 // class names, returns size of the cpool raw bytes.
2101 jint ConstantPool::hash_entries_to(SymbolHashMap *symmap,
2102                                           SymbolHashMap *classmap) {
2103   jint size = 0;
2104 
2105   for (u2 idx = 1; idx < length(); idx++) {
2106     u2 tag = tag_at(idx).value();
2107     size += cpool_entry_size(idx);
2108 
2109     switch(tag) {
2110       case JVM_CONSTANT_Utf8: {
2111         Symbol* sym = symbol_at(idx);
2112         symmap->add_entry(sym, idx);
2113         DBG(printf("adding symbol entry %s = %d\n", sym->as_utf8(), idx));
2114         break;
2115       }
2116       case JVM_CONSTANT_Class:
2117       case JVM_CONSTANT_UnresolvedClass:
2118       case JVM_CONSTANT_UnresolvedClassInError: {
2119         Symbol* sym = klass_name_at(idx);
2120         classmap->add_entry(sym, idx);
2121         DBG(printf("adding class entry %s = %d\n", sym->as_utf8(), idx));
2122         break;
2123       }
2124       case JVM_CONSTANT_Long:
2125       case JVM_CONSTANT_Double: {
2126         idx++; // Both Long and Double take two cpool slots
2127         break;
2128       }
2129     }
2130   }
2131   return size;
2132 } /* end hash_utf8_entries_to */
2133 
2134 
2135 // Copy cpool bytes.
2136 // Returns:
2137 //    0, in case of OutOfMemoryError
2138 //   -1, in case of internal error
2139 //  > 0, count of the raw cpool bytes that have been copied
2140 int ConstantPool::copy_cpool_bytes(int cpool_size,
2141                                           SymbolHashMap* tbl,
2142                                           unsigned char *bytes) {
2143   u2   idx1, idx2;
2144   jint size  = 0;
2145   jint cnt   = length();
2146   unsigned char *start_bytes = bytes;
2147 
2148   for (jint idx = 1; idx < cnt; idx++) {
2149     u1   tag      = tag_at(idx).value();
2150     jint ent_size = cpool_entry_size(idx);
2151 
2152     assert(size + ent_size <= cpool_size, "Size mismatch");
2153 
2154     *bytes = tag;
2155     DBG(printf("#%03hd tag=%03hd, ", (short)idx, (short)tag));
2156     switch(tag) {
2157       case JVM_CONSTANT_Invalid: {
2158         DBG(printf("JVM_CONSTANT_Invalid"));
2159         break;
2160       }
2161       case JVM_CONSTANT_Unicode: {
2162         assert(false, "Wrong constant pool tag: JVM_CONSTANT_Unicode");
2163         DBG(printf("JVM_CONSTANT_Unicode"));
2164         break;
2165       }
2166       case JVM_CONSTANT_Utf8: {
2167         Symbol* sym = symbol_at(idx);
2168         char*     str = sym->as_utf8();
2169         // Warning! It's crashing on x86 with len = sym->utf8_length()
2170         int       len = (int) strlen(str);
2171         Bytes::put_Java_u2((address) (bytes+1), (u2) len);
2172         for (int i = 0; i < len; i++) {
2173             bytes[3+i] = (u1) str[i];
2174         }
2175         DBG(printf("JVM_CONSTANT_Utf8: %s ", str));
2176         break;
2177       }
2178       case JVM_CONSTANT_Integer: {
2179         jint val = int_at(idx);
2180         Bytes::put_Java_u4((address) (bytes+1), *(u4*)&val);
2181         break;
2182       }
2183       case JVM_CONSTANT_Float: {
2184         jfloat val = float_at(idx);
2185         Bytes::put_Java_u4((address) (bytes+1), *(u4*)&val);
2186         break;
2187       }
2188       case JVM_CONSTANT_Long: {
2189         jlong val = long_at(idx);
2190         Bytes::put_Java_u8((address) (bytes+1), *(u8*)&val);
2191         idx++;             // Long takes two cpool slots
2192         break;
2193       }
2194       case JVM_CONSTANT_Double: {
2195         jdouble val = double_at(idx);
2196         Bytes::put_Java_u8((address) (bytes+1), *(u8*)&val);
2197         idx++;             // Double takes two cpool slots
2198         break;
2199       }
2200       case JVM_CONSTANT_Class:
2201       case JVM_CONSTANT_UnresolvedClass:
2202       case JVM_CONSTANT_UnresolvedClassInError: {

2203         *bytes = JVM_CONSTANT_Class;
2204         Symbol* sym = klass_name_at(idx);
2205         idx1 = tbl->symbol_to_value(sym);
2206         assert(idx1 != 0, "Have not found a hashtable entry");
2207         Bytes::put_Java_u2((address) (bytes+1), idx1);
2208         DBG(printf("JVM_CONSTANT_Class: idx=#%03hd, %s", idx1, sym->as_utf8()));
2209         break;
2210       }
2211       case JVM_CONSTANT_String: {
2212         *bytes = JVM_CONSTANT_String;
2213         Symbol* sym = unresolved_string_at(idx);
2214         idx1 = tbl->symbol_to_value(sym);
2215         assert(idx1 != 0, "Have not found a hashtable entry");
2216         Bytes::put_Java_u2((address) (bytes+1), idx1);
2217         DBG(printf("JVM_CONSTANT_String: idx=#%03hd, %s", idx1, sym->as_utf8()));
2218         break;
2219       }
2220       case JVM_CONSTANT_Fieldref:
2221       case JVM_CONSTANT_Methodref:
2222       case JVM_CONSTANT_InterfaceMethodref: {
2223         idx1 = uncached_klass_ref_index_at(idx);
2224         idx2 = uncached_name_and_type_ref_index_at(idx);
2225         Bytes::put_Java_u2((address) (bytes+1), idx1);
2226         Bytes::put_Java_u2((address) (bytes+3), idx2);
2227         DBG(printf("JVM_CONSTANT_Methodref: %hd %hd", idx1, idx2));
2228         break;
2229       }
2230       case JVM_CONSTANT_NameAndType: {
2231         idx1 = name_ref_index_at(idx);
2232         idx2 = signature_ref_index_at(idx);
2233         Bytes::put_Java_u2((address) (bytes+1), idx1);
2234         Bytes::put_Java_u2((address) (bytes+3), idx2);
2235         DBG(printf("JVM_CONSTANT_NameAndType: %hd %hd", idx1, idx2));
2236         break;
2237       }
2238       case JVM_CONSTANT_ClassIndex: {
2239         *bytes = JVM_CONSTANT_Class;
2240         idx1 = klass_index_at(idx);
2241         Bytes::put_Java_u2((address) (bytes+1), idx1);
2242         DBG(printf("JVM_CONSTANT_ClassIndex: %hd", idx1));
2243         break;
2244       }
2245       case JVM_CONSTANT_StringIndex: {
2246         *bytes = JVM_CONSTANT_String;
2247         idx1 = string_index_at(idx);
2248         Bytes::put_Java_u2((address) (bytes+1), idx1);
2249         DBG(printf("JVM_CONSTANT_StringIndex: %hd", idx1));
2250         break;
2251       }
2252       case JVM_CONSTANT_MethodHandle:
2253       case JVM_CONSTANT_MethodHandleInError: {
2254         *bytes = JVM_CONSTANT_MethodHandle;
2255         int kind = method_handle_ref_kind_at(idx);
2256         idx1 = method_handle_index_at(idx);
2257         *(bytes+1) = (unsigned char) kind;
2258         Bytes::put_Java_u2((address) (bytes+2), idx1);
2259         DBG(printf("JVM_CONSTANT_MethodHandle: %d %hd", kind, idx1));
2260         break;
2261       }
2262       case JVM_CONSTANT_MethodType:
2263       case JVM_CONSTANT_MethodTypeInError: {
2264         *bytes = JVM_CONSTANT_MethodType;
2265         idx1 = method_type_index_at(idx);
2266         Bytes::put_Java_u2((address) (bytes+1), idx1);
2267         DBG(printf("JVM_CONSTANT_MethodType: %hd", idx1));
2268         break;
2269       }
2270       case JVM_CONSTANT_Dynamic:
2271       case JVM_CONSTANT_DynamicInError: {
2272         *bytes = tag;
2273         idx1 = extract_low_short_from_int(*int_at_addr(idx));
2274         idx2 = extract_high_short_from_int(*int_at_addr(idx));
2275         assert(idx2 == bootstrap_name_and_type_ref_index_at(idx), "correct half of u4");
2276         Bytes::put_Java_u2((address) (bytes+1), idx1);
2277         Bytes::put_Java_u2((address) (bytes+3), idx2);
2278         DBG(printf("JVM_CONSTANT_Dynamic: %hd %hd", idx1, idx2));
2279         break;
2280       }
2281       case JVM_CONSTANT_InvokeDynamic: {
2282         *bytes = tag;
2283         idx1 = extract_low_short_from_int(*int_at_addr(idx));
2284         idx2 = extract_high_short_from_int(*int_at_addr(idx));
2285         assert(idx2 == bootstrap_name_and_type_ref_index_at(idx), "correct half of u4");
2286         Bytes::put_Java_u2((address) (bytes+1), idx1);
2287         Bytes::put_Java_u2((address) (bytes+3), idx2);
2288         DBG(printf("JVM_CONSTANT_InvokeDynamic: %hd %hd", idx1, idx2));
2289         break;
2290       }
2291     }
2292     DBG(printf("\n"));
2293     bytes += ent_size;
2294     size  += ent_size;
2295   }
2296   assert(size == cpool_size, "Size mismatch");
2297 
2298   // Keep temorarily for debugging until it's stable.
2299   DBG(print_cpool_bytes(cnt, start_bytes));
2300   return (int)(bytes - start_bytes);
2301 } /* end copy_cpool_bytes */
2302 
2303 #undef DBG
2304 
2305 
2306 void ConstantPool::set_on_stack(const bool value) {
2307   if (value) {
2308     // Only record if it's not already set.
2309     if (!on_stack()) {
2310       assert(!is_shared(), "should always be set for shared constant pools");
2311       _flags |= _on_stack;
2312       MetadataOnStackMark::record(this);
2313     }
2314   } else {
2315     // Clearing is done single-threadedly.
2316     if (!is_shared()) {
2317       _flags &= ~_on_stack;
2318     }
2319   }
2320 }
2321 
2322 // JSR 292 support for patching constant pool oops after the class is linked and
2323 // the oop array for resolved references are created.
2324 // We can't do this during classfile parsing, which is how the other indexes are
2325 // patched.  The other patches are applied early for some error checking
2326 // so only defer the pseudo_strings.
2327 void ConstantPool::patch_resolved_references(GrowableArray<Handle>* cp_patches) {
2328   for (int index = 1; index < cp_patches->length(); index++) { // Index 0 is unused
2329     Handle patch = cp_patches->at(index);
2330     if (patch.not_null()) {
2331       assert (tag_at(index).is_string(), "should only be string left");
2332       // Patching a string means pre-resolving it.
2333       // The spelling in the constant pool is ignored.
2334       // The constant reference may be any object whatever.
2335       // If it is not a real interned string, the constant is referred
2336       // to as a "pseudo-string", and must be presented to the CP
2337       // explicitly, because it may require scavenging.
2338       int obj_index = cp_to_object_index(index);
2339       pseudo_string_at_put(index, obj_index, patch());
2340      DEBUG_ONLY(cp_patches->at_put(index, Handle());)
2341     }
2342   }
2343 #ifdef ASSERT
2344   // Ensure that all the patches have been used.
2345   for (int index = 0; index < cp_patches->length(); index++) {
2346     assert(cp_patches->at(index).is_null(),
2347            "Unused constant pool patch at %d in class file %s",
2348            index,
2349            pool_holder()->external_name());
2350   }
2351 #endif // ASSERT
2352 }
2353 
2354 // Printing
2355 
2356 void ConstantPool::print_on(outputStream* st) const {
2357   assert(is_constantPool(), "must be constantPool");
2358   st->print_cr("%s", internal_name());
2359   if (flags() != 0) {
2360     st->print(" - flags: 0x%x", flags());
2361     if (has_preresolution()) st->print(" has_preresolution");
2362     if (on_stack()) st->print(" on_stack");
2363     st->cr();
2364   }
2365   if (pool_holder() != NULL) {
2366     st->print_cr(" - holder: " INTPTR_FORMAT, p2i(pool_holder()));
2367   }
2368   st->print_cr(" - cache: " INTPTR_FORMAT, p2i(cache()));
2369   st->print_cr(" - resolved_references: " INTPTR_FORMAT, p2i(resolved_references()));
2370   st->print_cr(" - reference_map: " INTPTR_FORMAT, p2i(reference_map()));
2371   st->print_cr(" - resolved_klasses: " INTPTR_FORMAT, p2i(resolved_klasses()));
2372 
2373   for (int index = 1; index < length(); index++) {      // Index 0 is unused
2374     ((ConstantPool*)this)->print_entry_on(index, st);
2375     switch (tag_at(index).value()) {
2376       case JVM_CONSTANT_Long :
2377       case JVM_CONSTANT_Double :
2378         index++;   // Skip entry following eigth-byte constant
2379     }
2380 
2381   }
2382   st->cr();
2383 }
2384 
2385 // Print one constant pool entry
2386 void ConstantPool::print_entry_on(const int index, outputStream* st) {
2387   EXCEPTION_MARK;
2388   st->print(" - %3d : ", index);
2389   tag_at(index).print_on(st);
2390   st->print(" : ");
2391   switch (tag_at(index).value()) {
2392     case JVM_CONSTANT_Class :
2393       { Klass* k = klass_at(index, CATCH);
2394         guarantee(k != NULL, "need klass");
2395         k->print_value_on(st);
2396         st->print(" {" PTR_FORMAT "}", p2i(k));
2397       }
2398       break;
2399     case JVM_CONSTANT_Fieldref :
2400     case JVM_CONSTANT_Methodref :
2401     case JVM_CONSTANT_InterfaceMethodref :
2402       st->print("klass_index=%d", uncached_klass_ref_index_at(index));
2403       st->print(" name_and_type_index=%d", uncached_name_and_type_ref_index_at(index));
2404       break;
2405     case JVM_CONSTANT_String :
2406       if (is_pseudo_string_at(index)) {
2407         oop anObj = pseudo_string_at(index);
2408         anObj->print_value_on(st);
2409         st->print(" {" PTR_FORMAT "}", p2i(anObj));
2410       } else {
2411         unresolved_string_at(index)->print_value_on(st);
2412       }
2413       break;
2414     case JVM_CONSTANT_Integer :
2415       st->print("%d", int_at(index));
2416       break;
2417     case JVM_CONSTANT_Float :
2418       st->print("%f", float_at(index));
2419       break;
2420     case JVM_CONSTANT_Long :
2421       st->print_jlong(long_at(index));
2422       break;
2423     case JVM_CONSTANT_Double :
2424       st->print("%lf", double_at(index));
2425       break;
2426     case JVM_CONSTANT_NameAndType :
2427       st->print("name_index=%d", name_ref_index_at(index));
2428       st->print(" signature_index=%d", signature_ref_index_at(index));
2429       break;
2430     case JVM_CONSTANT_Utf8 :
2431       symbol_at(index)->print_value_on(st);
2432       break;
2433     case JVM_CONSTANT_ClassIndex: {
2434         int name_index = *int_at_addr(index);
2435         st->print("klass_index=%d ", name_index);
2436         symbol_at(name_index)->print_value_on(st);
2437       }
2438       break;
2439     case JVM_CONSTANT_UnresolvedClass :               // fall-through
2440     case JVM_CONSTANT_UnresolvedClassInError: {
2441         CPKlassSlot kslot = klass_slot_at(index);
2442         int resolved_klass_index = kslot.resolved_klass_index();
2443         int name_index = kslot.name_index();
2444         assert(tag_at(name_index).is_symbol(), "sanity");
2445 
2446         Klass* klass = resolved_klasses()->at(resolved_klass_index);
2447         if (klass != NULL) {
2448           klass->print_value_on(st);
2449         } else {
2450           symbol_at(name_index)->print_value_on(st);
2451         }
2452       }
2453       break;
2454     case JVM_CONSTANT_MethodHandle :
2455     case JVM_CONSTANT_MethodHandleInError :
2456       st->print("ref_kind=%d", method_handle_ref_kind_at(index));
2457       st->print(" ref_index=%d", method_handle_index_at(index));
2458       break;
2459     case JVM_CONSTANT_MethodType :
2460     case JVM_CONSTANT_MethodTypeInError :
2461       st->print("signature_index=%d", method_type_index_at(index));
2462       break;
2463     case JVM_CONSTANT_Dynamic :
2464     case JVM_CONSTANT_DynamicInError :
2465       {
2466         st->print("bootstrap_method_index=%d", bootstrap_method_ref_index_at(index));
2467         st->print(" type_index=%d", bootstrap_name_and_type_ref_index_at(index));
2468         int argc = bootstrap_argument_count_at(index);
2469         if (argc > 0) {
2470           for (int arg_i = 0; arg_i < argc; arg_i++) {
2471             int arg = bootstrap_argument_index_at(index, arg_i);
2472             st->print((arg_i == 0 ? " arguments={%d" : ", %d"), arg);
2473           }
2474           st->print("}");
2475         }
2476       }
2477       break;
2478     case JVM_CONSTANT_InvokeDynamic :
2479       {
2480         st->print("bootstrap_method_index=%d", bootstrap_method_ref_index_at(index));
2481         st->print(" name_and_type_index=%d", bootstrap_name_and_type_ref_index_at(index));
2482         int argc = bootstrap_argument_count_at(index);
2483         if (argc > 0) {
2484           for (int arg_i = 0; arg_i < argc; arg_i++) {
2485             int arg = bootstrap_argument_index_at(index, arg_i);
2486             st->print((arg_i == 0 ? " arguments={%d" : ", %d"), arg);
2487           }
2488           st->print("}");
2489         }
2490       }
2491       break;
2492     default:
2493       ShouldNotReachHere();
2494       break;
2495   }
2496   st->cr();
2497 }
2498 
2499 void ConstantPool::print_value_on(outputStream* st) const {
2500   assert(is_constantPool(), "must be constantPool");
2501   st->print("constant pool [%d]", length());
2502   if (has_preresolution()) st->print("/preresolution");
2503   if (operands() != NULL)  st->print("/operands[%d]", operands()->length());
2504   print_address_on(st);
2505   if (pool_holder() != NULL) {
2506     st->print(" for ");
2507     pool_holder()->print_value_on(st);
2508     bool extra = (pool_holder()->constants() != this);
2509     if (extra)  st->print(" (extra)");
2510   }
2511   if (cache() != NULL) {
2512     st->print(" cache=" PTR_FORMAT, p2i(cache()));
2513   }
2514 }
2515 
2516 #if INCLUDE_SERVICES
2517 // Size Statistics
2518 void ConstantPool::collect_statistics(KlassSizeStats *sz) const {
2519   sz->_cp_all_bytes += (sz->_cp_bytes          = sz->count(this));
2520   sz->_cp_all_bytes += (sz->_cp_tags_bytes     = sz->count_array(tags()));
2521   sz->_cp_all_bytes += (sz->_cp_cache_bytes    = sz->count(cache()));
2522   sz->_cp_all_bytes += (sz->_cp_operands_bytes = sz->count_array(operands()));
2523   sz->_cp_all_bytes += (sz->_cp_refmap_bytes   = sz->count_array(reference_map()));
2524 
2525   sz->_ro_bytes += sz->_cp_operands_bytes + sz->_cp_tags_bytes +
2526                    sz->_cp_refmap_bytes;
2527   sz->_rw_bytes += sz->_cp_bytes + sz->_cp_cache_bytes;
2528 }
2529 #endif // INCLUDE_SERVICES
2530 
2531 // Verification
2532 
2533 void ConstantPool::verify_on(outputStream* st) {
2534   guarantee(is_constantPool(), "object must be constant pool");
2535   for (int i = 0; i< length();  i++) {
2536     constantTag tag = tag_at(i);
2537     if (tag.is_klass() || tag.is_unresolved_klass()) {
2538       guarantee(klass_name_at(i)->refcount() != 0, "should have nonzero reference count");
2539     } else if (tag.is_symbol()) {
2540       CPSlot entry = slot_at(i);
2541       guarantee(entry.get_symbol()->refcount() != 0, "should have nonzero reference count");
2542     } else if (tag.is_string()) {
2543       CPSlot entry = slot_at(i);
2544       guarantee(entry.get_symbol()->refcount() != 0, "should have nonzero reference count");
2545     }
2546   }
2547   if (pool_holder() != NULL) {
2548     // Note: pool_holder() can be NULL in temporary constant pools
2549     // used during constant pool merging
2550     guarantee(pool_holder()->is_klass(),    "should be klass");
2551   }
2552 }
2553 
2554 
2555 SymbolHashMap::~SymbolHashMap() {
2556   SymbolHashMapEntry* next;
2557   for (int i = 0; i < _table_size; i++) {
2558     for (SymbolHashMapEntry* cur = bucket(i); cur != NULL; cur = next) {
2559       next = cur->next();
2560       delete(cur);
2561     }
2562   }
2563   FREE_C_HEAP_ARRAY(SymbolHashMapBucket, _buckets);
2564 }
2565 
2566 void SymbolHashMap::add_entry(Symbol* sym, u2 value) {
2567   char *str = sym->as_utf8();
2568   unsigned int hash = compute_hash(str, sym->utf8_length());
2569   unsigned int index = hash % table_size();
2570 
2571   // check if already in map
2572   // we prefer the first entry since it is more likely to be what was used in
2573   // the class file
2574   for (SymbolHashMapEntry *en = bucket(index); en != NULL; en = en->next()) {
2575     assert(en->symbol() != NULL, "SymbolHashMapEntry symbol is NULL");
2576     if (en->hash() == hash && en->symbol() == sym) {
2577         return;  // already there
2578     }
2579   }
2580 
2581   SymbolHashMapEntry* entry = new SymbolHashMapEntry(hash, sym, value);
2582   entry->set_next(bucket(index));
2583   _buckets[index].set_entry(entry);
2584   assert(entry->symbol() != NULL, "SymbolHashMapEntry symbol is NULL");
2585 }
2586 
2587 SymbolHashMapEntry* SymbolHashMap::find_entry(Symbol* sym) {
2588   assert(sym != NULL, "SymbolHashMap::find_entry - symbol is NULL");
2589   char *str = sym->as_utf8();
2590   int   len = sym->utf8_length();
2591   unsigned int hash = SymbolHashMap::compute_hash(str, len);
2592   unsigned int index = hash % table_size();
2593   for (SymbolHashMapEntry *en = bucket(index); en != NULL; en = en->next()) {
2594     assert(en->symbol() != NULL, "SymbolHashMapEntry symbol is NULL");
2595     if (en->hash() == hash && en->symbol() == sym) {
2596       return en;
2597     }
2598   }
2599   return NULL;
2600 }
2601 
2602 void SymbolHashMap::initialize_table(int table_size) {
2603   _table_size = table_size;
2604   _buckets = NEW_C_HEAP_ARRAY(SymbolHashMapBucket, table_size, mtSymbol);
2605   for (int index = 0; index < table_size; index++) {
2606     _buckets[index].clear();
2607   }
2608 }
--- EOF ---