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src/hotspot/share/interpreter/interpreterRuntime.cpp

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   1 /*
   2  * Copyright (c) 1997, 2025, 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 "classfile/javaClasses.inline.hpp"
  26 #include "classfile/symbolTable.hpp"

  27 #include "classfile/vmClasses.hpp"
  28 #include "classfile/vmSymbols.hpp"
  29 #include "code/codeCache.hpp"
  30 #include "compiler/compilationPolicy.hpp"
  31 #include "compiler/compileBroker.hpp"
  32 #include "compiler/disassembler.hpp"
  33 #include "gc/shared/barrierSetNMethod.hpp"
  34 #include "gc/shared/collectedHeap.hpp"
  35 #include "interpreter/bytecodeTracer.hpp"
  36 #include "interpreter/interpreter.hpp"
  37 #include "interpreter/interpreterRuntime.hpp"
  38 #include "interpreter/linkResolver.hpp"
  39 #include "interpreter/templateTable.hpp"
  40 #include "jvm_io.h"
  41 #include "logging/log.hpp"
  42 #include "memory/oopFactory.hpp"
  43 #include "memory/resourceArea.hpp"
  44 #include "memory/universe.hpp"
  45 #include "oops/constantPool.inline.hpp"
  46 #include "oops/cpCache.inline.hpp"



  47 #include "oops/instanceKlass.inline.hpp"
  48 #include "oops/klass.inline.hpp"
  49 #include "oops/method.inline.hpp"
  50 #include "oops/methodData.hpp"
  51 #include "oops/objArrayKlass.hpp"
  52 #include "oops/objArrayOop.inline.hpp"
  53 #include "oops/oop.inline.hpp"
  54 #include "oops/symbol.hpp"
  55 #include "prims/jvmtiExport.hpp"
  56 #include "prims/methodHandles.hpp"
  57 #include "prims/nativeLookup.hpp"
  58 #include "runtime/atomicAccess.hpp"
  59 #include "runtime/continuation.hpp"
  60 #include "runtime/deoptimization.hpp"
  61 #include "runtime/fieldDescriptor.inline.hpp"
  62 #include "runtime/frame.inline.hpp"
  63 #include "runtime/handles.inline.hpp"
  64 #include "runtime/icache.hpp"
  65 #include "runtime/interfaceSupport.inline.hpp"
  66 #include "runtime/java.hpp"
  67 #include "runtime/javaCalls.hpp"
  68 #include "runtime/jfieldIDWorkaround.hpp"
  69 #include "runtime/osThread.hpp"
  70 #include "runtime/sharedRuntime.hpp"
  71 #include "runtime/stackWatermarkSet.hpp"
  72 #include "runtime/stubRoutines.hpp"
  73 #include "runtime/synchronizer.hpp"
  74 #include "utilities/align.hpp"
  75 #include "utilities/checkedCast.hpp"
  76 #include "utilities/copy.hpp"
  77 #include "utilities/events.hpp"

  78 #if INCLUDE_JFR
  79 #include "jfr/jfr.inline.hpp"
  80 #endif
  81 
  82 // Helper class to access current interpreter state
  83 class LastFrameAccessor : public StackObj {
  84   frame _last_frame;
  85 public:
  86   LastFrameAccessor(JavaThread* current) {
  87     assert(current == Thread::current(), "sanity");
  88     _last_frame = current->last_frame();
  89   }
  90   bool is_interpreted_frame() const              { return _last_frame.is_interpreted_frame(); }
  91   Method*   method() const                       { return _last_frame.interpreter_frame_method(); }
  92   address   bcp() const                          { return _last_frame.interpreter_frame_bcp(); }
  93   int       bci() const                          { return _last_frame.interpreter_frame_bci(); }
  94   address   mdp() const                          { return _last_frame.interpreter_frame_mdp(); }
  95 
  96   void      set_bcp(address bcp)                 { _last_frame.interpreter_frame_set_bcp(bcp); }
  97   void      set_mdp(address dp)                  { _last_frame.interpreter_frame_set_mdp(dp); }

 208 JRT_END
 209 
 210 
 211 //------------------------------------------------------------------------------------------------------------------------
 212 // Allocation
 213 
 214 JRT_ENTRY(void, InterpreterRuntime::_new(JavaThread* current, ConstantPool* pool, int index))
 215   Klass* k = pool->klass_at(index, CHECK);
 216   InstanceKlass* klass = InstanceKlass::cast(k);
 217 
 218   // Make sure we are not instantiating an abstract klass
 219   klass->check_valid_for_instantiation(true, CHECK);
 220 
 221   // Make sure klass is initialized
 222   klass->initialize_preemptable(CHECK_AND_CLEAR_PREEMPTED);
 223 
 224   oop obj = klass->allocate_instance(CHECK);
 225   current->set_vm_result_oop(obj);
 226 JRT_END
 227 










































 228 
 229 JRT_ENTRY(void, InterpreterRuntime::newarray(JavaThread* current, BasicType type, jint size))
 230   oop obj = oopFactory::new_typeArray(type, size, CHECK);
 231   current->set_vm_result_oop(obj);
 232 JRT_END
 233 
 234 
 235 JRT_ENTRY(void, InterpreterRuntime::anewarray(JavaThread* current, ConstantPool* pool, int index, jint size))
 236   Klass*    klass = pool->klass_at(index, CHECK);
 237   objArrayOop obj = oopFactory::new_objArray(klass, size, CHECK);
 238   current->set_vm_result_oop(obj);
 239 JRT_END
 240 












 241 
 242 JRT_ENTRY(void, InterpreterRuntime::multianewarray(JavaThread* current, jint* first_size_address))
 243   // We may want to pass in more arguments - could make this slightly faster
 244   LastFrameAccessor last_frame(current);
 245   ConstantPool* constants = last_frame.method()->constants();
 246   int          i = last_frame.get_index_u2(Bytecodes::_multianewarray);
 247   Klass* klass   = constants->klass_at(i, CHECK);
 248   int   nof_dims = last_frame.number_of_dimensions();
 249   assert(klass->is_klass(), "not a class");
 250   assert(nof_dims >= 1, "multianewarray rank must be nonzero");
 251 
 252   // We must create an array of jints to pass to multi_allocate.
 253   ResourceMark rm(current);
 254   const int small_dims = 10;
 255   jint dim_array[small_dims];
 256   jint *dims = &dim_array[0];
 257   if (nof_dims > small_dims) {
 258     dims = (jint*) NEW_RESOURCE_ARRAY(jint, nof_dims);
 259   }
 260   for (int index = 0; index < nof_dims; index++) {
 261     // offset from first_size_address is addressed as local[index]
 262     int n = Interpreter::local_offset_in_bytes(index)/jintSize;
 263     dims[index] = first_size_address[n];
 264   }
 265   oop obj = ArrayKlass::cast(klass)->multi_allocate(nof_dims, dims, CHECK);
 266   current->set_vm_result_oop(obj);
 267 JRT_END
 268 
 269 
 270 JRT_ENTRY(void, InterpreterRuntime::register_finalizer(JavaThread* current, oopDesc* obj))
 271   assert(oopDesc::is_oop(obj), "must be a valid oop");
 272   assert(obj->klass()->has_finalizer(), "shouldn't be here otherwise");
 273   InstanceKlass::register_finalizer(instanceOop(obj), CHECK);
 274 JRT_END
 275 
























 276 
 277 // Quicken instance-of and check-cast bytecodes
 278 JRT_ENTRY(void, InterpreterRuntime::quicken_io_cc(JavaThread* current))
 279   // Force resolving; quicken the bytecode
 280   LastFrameAccessor last_frame(current);
 281   int which = last_frame.get_index_u2(Bytecodes::_checkcast);
 282   ConstantPool* cpool = last_frame.method()->constants();
 283   // We'd expect to assert that we're only here to quicken bytecodes, but in a multithreaded
 284   // program we might have seen an unquick'd bytecode in the interpreter but have another
 285   // thread quicken the bytecode before we get here.
 286   // assert( cpool->tag_at(which).is_unresolved_klass(), "should only come here to quicken bytecodes" );
 287   Klass* klass = cpool->klass_at(which, CHECK);
 288   current->set_vm_result_metadata(klass);
 289 JRT_END
 290 
 291 
 292 //------------------------------------------------------------------------------------------------------------------------
 293 // Exceptions
 294 
 295 void InterpreterRuntime::note_trap_inner(JavaThread* current, int reason,

 603 // and therefore we don't have the receiver object at our fingertips. (Though,
 604 // on some platforms the receiver still resides in a register...). Thus,
 605 // we have no choice but print an error message not containing the receiver
 606 // type.
 607 JRT_ENTRY(void, InterpreterRuntime::throw_AbstractMethodErrorWithMethod(JavaThread* current,
 608                                                                         Method* missingMethod))
 609   ResourceMark rm(current);
 610   assert(missingMethod != nullptr, "sanity");
 611   methodHandle m(current, missingMethod);
 612   LinkResolver::throw_abstract_method_error(m, THREAD);
 613 JRT_END
 614 
 615 JRT_ENTRY(void, InterpreterRuntime::throw_AbstractMethodErrorVerbose(JavaThread* current,
 616                                                                      Klass* recvKlass,
 617                                                                      Method* missingMethod))
 618   ResourceMark rm(current);
 619   methodHandle mh = methodHandle(current, missingMethod);
 620   LinkResolver::throw_abstract_method_error(mh, recvKlass, THREAD);
 621 JRT_END
 622 




 623 
 624 JRT_ENTRY(void, InterpreterRuntime::throw_IncompatibleClassChangeError(JavaThread* current))
 625   THROW(vmSymbols::java_lang_IncompatibleClassChangeError());
 626 JRT_END
 627 
 628 JRT_ENTRY(void, InterpreterRuntime::throw_IncompatibleClassChangeErrorVerbose(JavaThread* current,
 629                                                                               Klass* recvKlass,
 630                                                                               Klass* interfaceKlass))
 631   ResourceMark rm(current);
 632   char buf[1000];
 633   buf[0] = '\0';
 634   jio_snprintf(buf, sizeof(buf),
 635                "Class %s does not implement the requested interface %s",
 636                recvKlass ? recvKlass->external_name() : "nullptr",
 637                interfaceKlass ? interfaceKlass->external_name() : "nullptr");
 638   THROW_MSG(vmSymbols::java_lang_IncompatibleClassChangeError(), buf);
 639 JRT_END
 640 
 641 JRT_ENTRY(void, InterpreterRuntime::throw_NullPointerException(JavaThread* current))
 642   THROW(vmSymbols::java_lang_NullPointerException());

 682 
 683   // Resolution of put instructions to final instance fields with invalid updates (i.e.,
 684   // to final instance fields with updates originating from a method different than <init>)
 685   // is inhibited. A putfield instruction targeting an instance final field must throw
 686   // an IllegalAccessError if the instruction is not in an instance
 687   // initializer method <init>. If resolution were not inhibited, a putfield
 688   // in an initializer method could be resolved in the initializer. Subsequent
 689   // putfield instructions to the same field would then use cached information.
 690   // As a result, those instructions would not pass through the VM. That is,
 691   // checks in resolve_field_access() would not be executed for those instructions
 692   // and the required IllegalAccessError would not be thrown.
 693   //
 694   // Also, we need to delay resolving getstatic and putstatic instructions until the
 695   // class is initialized.  This is required so that access to the static
 696   // field will call the initialization function every time until the class
 697   // is completely initialized ala. in 2.17.5 in JVM Specification.
 698   InstanceKlass* klass = info.field_holder();
 699   bool uninitialized_static = is_static && !klass->is_initialized();
 700   bool has_initialized_final_update = info.field_holder()->major_version() >= 53 &&
 701                                       info.has_initialized_final_update();

 702   assert(!(has_initialized_final_update && !info.access_flags().is_final()), "Fields with initialized final updates must be final");
 703 
 704   Bytecodes::Code get_code = (Bytecodes::Code)0;
 705   Bytecodes::Code put_code = (Bytecodes::Code)0;
 706   if (!uninitialized_static || VM_Version::supports_fast_class_init_checks()) {













 707     get_code = ((is_static) ? Bytecodes::_getstatic : Bytecodes::_getfield);
 708     if ((is_put && !has_initialized_final_update) || !info.access_flags().is_final()) {
 709       put_code = ((is_static) ? Bytecodes::_putstatic : Bytecodes::_putfield);
 710     }
 711   }
 712 
 713   ResolvedFieldEntry* entry = pool->resolved_field_entry_at(field_index);
 714   entry->set_flags(info.access_flags().is_final(), info.access_flags().is_volatile());





 715   entry->fill_in(info.field_holder(), info.offset(),
 716                  checked_cast<u2>(info.index()), checked_cast<u1>(state),
 717                  static_cast<u1>(get_code), static_cast<u1>(put_code));
 718 }
 719 
 720 
 721 //------------------------------------------------------------------------------------------------------------------------
 722 // Synchronization
 723 //
 724 // The interpreter's synchronization code is factored out so that it can
 725 // be shared by method invocation and synchronized blocks.
 726 //%note synchronization_3
 727 
 728 //%note monitor_1
 729 JRT_ENTRY_NO_ASYNC(void, InterpreterRuntime::monitorenter(JavaThread* current, BasicObjectLock* elem))
 730 #ifdef ASSERT
 731   current->last_frame().interpreter_frame_verify_monitor(elem);
 732 #endif
 733   Handle h_obj(current, elem->obj());
 734   assert(Universe::heap()->is_in_or_null(h_obj()),

 741 #endif
 742 JRT_END
 743 
 744 JRT_LEAF(void, InterpreterRuntime::monitorexit(BasicObjectLock* elem))
 745   oop obj = elem->obj();
 746   assert(Universe::heap()->is_in(obj), "must be an object");
 747   // The object could become unlocked through a JNI call, which we have no other checks for.
 748   // Give a fatal message if CheckJNICalls. Otherwise we ignore it.
 749   if (obj->is_unlocked()) {
 750     if (CheckJNICalls) {
 751       fatal("Object has been unlocked by JNI");
 752     }
 753     return;
 754   }
 755   ObjectSynchronizer::exit(obj, elem->lock(), JavaThread::current());
 756   // Free entry. If it is not cleared, the exception handling code will try to unlock the monitor
 757   // again at method exit or in the case of an exception.
 758   elem->set_obj(nullptr);
 759 JRT_END
 760 
 761 
 762 JRT_ENTRY(void, InterpreterRuntime::throw_illegal_monitor_state_exception(JavaThread* current))
 763   THROW(vmSymbols::java_lang_IllegalMonitorStateException());
 764 JRT_END
 765 
 766 
 767 JRT_ENTRY(void, InterpreterRuntime::new_illegal_monitor_state_exception(JavaThread* current))
 768   // Returns an illegal exception to install into the current thread. The
 769   // pending_exception flag is cleared so normal exception handling does not
 770   // trigger. Any current installed exception will be overwritten. This
 771   // method will be called during an exception unwind.
 772 
 773   assert(!HAS_PENDING_EXCEPTION, "no pending exception");
 774   Handle exception(current, current->vm_result_oop());
 775   assert(exception() != nullptr, "vm result should be set");
 776   current->set_vm_result_oop(nullptr); // clear vm result before continuing (may cause memory leaks and assert failures)
 777   exception = get_preinitialized_exception(vmClasses::IllegalMonitorStateException_klass(), CATCH);
 778   current->set_vm_result_oop(exception());
 779 JRT_END
 780 















 781 
 782 //------------------------------------------------------------------------------------------------------------------------
 783 // Invokes
 784 
 785 JRT_ENTRY(Bytecodes::Code, InterpreterRuntime::get_original_bytecode_at(JavaThread* current, Method* method, address bcp))
 786   return method->orig_bytecode_at(method->bci_from(bcp));
 787 JRT_END
 788 
 789 JRT_ENTRY(void, InterpreterRuntime::set_original_bytecode_at(JavaThread* current, Method* method, address bcp, Bytecodes::Code new_code))
 790   method->set_orig_bytecode_at(method->bci_from(bcp), new_code);
 791 JRT_END
 792 
 793 JRT_ENTRY(void, InterpreterRuntime::_breakpoint(JavaThread* current, Method* method, address bcp))
 794   JvmtiExport::post_raw_breakpoint(current, method, bcp);
 795 JRT_END
 796 
 797 void InterpreterRuntime::resolve_invoke(Bytecodes::Code bytecode, TRAPS) {
 798   JavaThread* current = THREAD;
 799   LastFrameAccessor last_frame(current);
 800   // extract receiver from the outgoing argument list if necessary

1174     JvmtiExport::at_single_stepping_point(current, last_frame.method(), last_frame.bcp());
1175   }
1176 JRT_END
1177 
1178 JRT_LEAF(void, InterpreterRuntime::at_unwind(JavaThread* current))
1179   assert(current == JavaThread::current(), "pre-condition");
1180   JFR_ONLY(Jfr::check_and_process_sample_request(current);)
1181   // This function is called by the interpreter when the return poll found a reason
1182   // to call the VM. The reason could be that we are returning into a not yet safe
1183   // to access frame. We handle that below.
1184   // Note that this path does not check for single stepping, because we do not want
1185   // to single step when unwinding frames for an exception being thrown. Instead,
1186   // such single stepping code will use the safepoint table, which will use the
1187   // InterpreterRuntime::at_safepoint callback.
1188   StackWatermarkSet::before_unwind(current);
1189 JRT_END
1190 
1191 JRT_ENTRY(void, InterpreterRuntime::post_field_access(JavaThread* current, oopDesc* obj,
1192                                                       ResolvedFieldEntry *entry))
1193 

1194   // check the access_flags for the field in the klass
1195 
1196   InstanceKlass* ik = entry->field_holder();
1197   int index = entry->field_index();
1198   if (!ik->field_status(index).is_access_watched()) return;
1199 
1200   bool is_static = (obj == nullptr);

1201   HandleMark hm(current);
1202 
1203   Handle h_obj;
1204   if (!is_static) {
1205     // non-static field accessors have an object, but we need a handle
1206     h_obj = Handle(current, obj);
1207   }
1208   InstanceKlass* field_holder = entry->field_holder(); // HERE
1209   jfieldID fid = jfieldIDWorkaround::to_jfieldID(field_holder, entry->field_offset(), is_static);
1210   LastFrameAccessor last_frame(current);
1211   JvmtiExport::post_field_access(current, last_frame.method(), last_frame.bcp(), field_holder, h_obj, fid);
1212 JRT_END
1213 
1214 JRT_ENTRY(void, InterpreterRuntime::post_field_modification(JavaThread* current, oopDesc* obj,
1215                                                             ResolvedFieldEntry *entry, jvalue *value))
1216 

1217   InstanceKlass* ik = entry->field_holder();
1218 
1219   // check the access_flags for the field in the klass
1220   int index = entry->field_index();
1221   // bail out if field modifications are not watched
1222   if (!ik->field_status(index).is_modification_watched()) return;
1223 
1224   char sig_type = '\0';
1225 
1226   switch((TosState)entry->tos_state()) {
1227     case btos: sig_type = JVM_SIGNATURE_BYTE;    break;
1228     case ztos: sig_type = JVM_SIGNATURE_BOOLEAN; break;
1229     case ctos: sig_type = JVM_SIGNATURE_CHAR;    break;
1230     case stos: sig_type = JVM_SIGNATURE_SHORT;   break;
1231     case itos: sig_type = JVM_SIGNATURE_INT;     break;
1232     case ftos: sig_type = JVM_SIGNATURE_FLOAT;   break;
1233     case atos: sig_type = JVM_SIGNATURE_CLASS;   break;
1234     case ltos: sig_type = JVM_SIGNATURE_LONG;    break;
1235     case dtos: sig_type = JVM_SIGNATURE_DOUBLE;  break;
1236     default:  ShouldNotReachHere(); return;
1237   }

1238   bool is_static = (obj == nullptr);

1239 
1240   HandleMark hm(current);
1241   jfieldID fid = jfieldIDWorkaround::to_jfieldID(ik, entry->field_offset(), is_static);
1242   jvalue fvalue;
1243 #ifdef _LP64
1244   fvalue = *value;
1245 #else
1246   // Long/double values are stored unaligned and also noncontiguously with
1247   // tagged stacks.  We can't just do a simple assignment even in the non-
1248   // J/D cases because a C++ compiler is allowed to assume that a jvalue is
1249   // 8-byte aligned, and interpreter stack slots are only 4-byte aligned.
1250   // We assume that the two halves of longs/doubles are stored in interpreter
1251   // stack slots in platform-endian order.
1252   jlong_accessor u;
1253   jint* newval = (jint*)value;
1254   u.words[0] = newval[0];
1255   u.words[1] = newval[Interpreter::stackElementWords]; // skip if tag
1256   fvalue.j = u.long_value;
1257 #endif // _LP64
1258 
1259   Handle h_obj;
1260   if (!is_static) {
1261     // non-static field accessors have an object, but we need a handle

   1 /*
   2  * Copyright (c) 1997, 2026, 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 "classfile/javaClasses.inline.hpp"
  26 #include "classfile/symbolTable.hpp"
  27 #include "classfile/systemDictionary.hpp"
  28 #include "classfile/vmClasses.hpp"
  29 #include "classfile/vmSymbols.hpp"
  30 #include "code/codeCache.hpp"
  31 #include "compiler/compilationPolicy.hpp"
  32 #include "compiler/compileBroker.hpp"
  33 #include "compiler/disassembler.hpp"
  34 #include "gc/shared/barrierSetNMethod.hpp"
  35 #include "gc/shared/collectedHeap.hpp"
  36 #include "interpreter/bytecodeTracer.hpp"
  37 #include "interpreter/interpreter.hpp"
  38 #include "interpreter/interpreterRuntime.hpp"
  39 #include "interpreter/linkResolver.hpp"
  40 #include "interpreter/templateTable.hpp"
  41 #include "jvm_io.h"
  42 #include "logging/log.hpp"
  43 #include "memory/oopFactory.hpp"
  44 #include "memory/resourceArea.hpp"
  45 #include "memory/universe.hpp"
  46 #include "oops/constantPool.inline.hpp"
  47 #include "oops/cpCache.inline.hpp"
  48 #include "oops/flatArrayKlass.hpp"
  49 #include "oops/flatArrayOop.inline.hpp"
  50 #include "oops/inlineKlass.inline.hpp"
  51 #include "oops/instanceKlass.inline.hpp"
  52 #include "oops/klass.inline.hpp"
  53 #include "oops/method.inline.hpp"
  54 #include "oops/methodData.hpp"
  55 #include "oops/objArrayKlass.hpp"
  56 #include "oops/objArrayOop.inline.hpp"
  57 #include "oops/oop.inline.hpp"
  58 #include "oops/symbol.hpp"
  59 #include "prims/jvmtiExport.hpp"
  60 #include "prims/methodHandles.hpp"
  61 #include "prims/nativeLookup.hpp"
  62 #include "runtime/atomicAccess.hpp"
  63 #include "runtime/continuation.hpp"
  64 #include "runtime/deoptimization.hpp"
  65 #include "runtime/fieldDescriptor.inline.hpp"
  66 #include "runtime/frame.inline.hpp"
  67 #include "runtime/handles.inline.hpp"
  68 #include "runtime/icache.hpp"
  69 #include "runtime/interfaceSupport.inline.hpp"
  70 #include "runtime/java.hpp"
  71 #include "runtime/javaCalls.hpp"
  72 #include "runtime/jfieldIDWorkaround.hpp"
  73 #include "runtime/osThread.hpp"
  74 #include "runtime/sharedRuntime.hpp"
  75 #include "runtime/stackWatermarkSet.hpp"
  76 #include "runtime/stubRoutines.hpp"
  77 #include "runtime/synchronizer.hpp"
  78 #include "utilities/align.hpp"
  79 #include "utilities/checkedCast.hpp"
  80 #include "utilities/copy.hpp"
  81 #include "utilities/events.hpp"
  82 #include "utilities/globalDefinitions.hpp"
  83 #if INCLUDE_JFR
  84 #include "jfr/jfr.inline.hpp"
  85 #endif
  86 
  87 // Helper class to access current interpreter state
  88 class LastFrameAccessor : public StackObj {
  89   frame _last_frame;
  90 public:
  91   LastFrameAccessor(JavaThread* current) {
  92     assert(current == Thread::current(), "sanity");
  93     _last_frame = current->last_frame();
  94   }
  95   bool is_interpreted_frame() const              { return _last_frame.is_interpreted_frame(); }
  96   Method*   method() const                       { return _last_frame.interpreter_frame_method(); }
  97   address   bcp() const                          { return _last_frame.interpreter_frame_bcp(); }
  98   int       bci() const                          { return _last_frame.interpreter_frame_bci(); }
  99   address   mdp() const                          { return _last_frame.interpreter_frame_mdp(); }
 100 
 101   void      set_bcp(address bcp)                 { _last_frame.interpreter_frame_set_bcp(bcp); }
 102   void      set_mdp(address dp)                  { _last_frame.interpreter_frame_set_mdp(dp); }

 213 JRT_END
 214 
 215 
 216 //------------------------------------------------------------------------------------------------------------------------
 217 // Allocation
 218 
 219 JRT_ENTRY(void, InterpreterRuntime::_new(JavaThread* current, ConstantPool* pool, int index))
 220   Klass* k = pool->klass_at(index, CHECK);
 221   InstanceKlass* klass = InstanceKlass::cast(k);
 222 
 223   // Make sure we are not instantiating an abstract klass
 224   klass->check_valid_for_instantiation(true, CHECK);
 225 
 226   // Make sure klass is initialized
 227   klass->initialize_preemptable(CHECK_AND_CLEAR_PREEMPTED);
 228 
 229   oop obj = klass->allocate_instance(CHECK);
 230   current->set_vm_result_oop(obj);
 231 JRT_END
 232 
 233 JRT_BLOCK_ENTRY(void, InterpreterRuntime::read_flat_field(JavaThread* current, oopDesc* obj, ResolvedFieldEntry* entry))
 234   assert(oopDesc::is_oop(obj), "Sanity check");
 235 
 236   InstanceKlass* holder = InstanceKlass::cast(entry->field_holder());
 237   assert(entry->field_holder()->field_is_flat(entry->field_index()), "Sanity check");
 238 
 239   InlineLayoutInfo* layout_info = holder->inline_layout_info_adr(entry->field_index());
 240   InlineKlass* field_klass = layout_info->klass();
 241   const LayoutKind lk = layout_info->kind();
 242   const int offset = entry->field_offset();
 243 
 244   // If the field is nullable and is marked null, return early.
 245   if (LayoutKindHelper::is_nullable_flat(lk) &&
 246       field_klass->is_payload_marked_as_null(cast_from_oop<address>(obj) + offset)) {
 247     current->set_vm_result_oop(nullptr);
 248     return;
 249   }
 250 
 251 #ifdef ASSERT
 252   fieldDescriptor fd;
 253   bool found = holder->find_field_from_offset(offset, false, &fd);
 254   assert(found, "Field not found");
 255   assert(fd.is_flat(), "Field must be flat");
 256 #endif // ASSERT
 257 
 258   JRT_BLOCK
 259     oop res = field_klass->read_payload_from_addr(obj, (size_t)offset, lk, CHECK);
 260     current->set_vm_result_oop(res);
 261   JRT_BLOCK_END
 262 JRT_END
 263 
 264 JRT_ENTRY(void, InterpreterRuntime::write_flat_field(JavaThread* current, oopDesc* obj, oopDesc* value, ResolvedFieldEntry* entry))
 265   assert(oopDesc::is_oop(obj), "Sanity check");
 266   Handle obj_h(THREAD, obj);
 267   assert(value == nullptr || oopDesc::is_oop(value), "Sanity check");
 268   Handle val_h(THREAD, value);
 269 
 270   InstanceKlass* holder = entry->field_holder();
 271   InlineLayoutInfo* li = holder->inline_layout_info_adr(entry->field_index());
 272   InlineKlass* vk = li->klass();
 273   vk->write_value_to_addr(val_h(), ((char*)(oopDesc*)obj_h()) + entry->field_offset(), li->kind(), CHECK);
 274 JRT_END
 275 
 276 JRT_ENTRY(void, InterpreterRuntime::newarray(JavaThread* current, BasicType type, jint size))
 277   oop obj = oopFactory::new_typeArray(type, size, CHECK);
 278   current->set_vm_result_oop(obj);
 279 JRT_END
 280 
 281 
 282 JRT_ENTRY(void, InterpreterRuntime::anewarray(JavaThread* current, ConstantPool* pool, int index, jint size))
 283   Klass*    klass = pool->klass_at(index, CHECK);
 284   arrayOop obj = oopFactory::new_objArray(klass, size, CHECK);
 285   current->set_vm_result_oop(obj);
 286 JRT_END
 287 
 288 JRT_ENTRY(void, InterpreterRuntime::flat_array_load(JavaThread* current, arrayOopDesc* array, int index))
 289   assert(array->is_flatArray(), "Must be");
 290   flatArrayOop farray = (flatArrayOop)array;
 291   oop res = farray->obj_at(index, CHECK);
 292   current->set_vm_result_oop(res);
 293 JRT_END
 294 
 295 JRT_ENTRY(void, InterpreterRuntime::flat_array_store(JavaThread* current, oopDesc* val, arrayOopDesc* array, int index))
 296   assert(array->is_flatArray(), "Must be");
 297   flatArrayOop farray = (flatArrayOop)array;
 298   farray->obj_at_put(index, val, CHECK);
 299 JRT_END
 300 
 301 JRT_ENTRY(void, InterpreterRuntime::multianewarray(JavaThread* current, jint* first_size_address))
 302   // We may want to pass in more arguments - could make this slightly faster
 303   LastFrameAccessor last_frame(current);
 304   ConstantPool* constants = last_frame.method()->constants();
 305   int i = last_frame.get_index_u2(Bytecodes::_multianewarray);
 306   Klass* klass = constants->klass_at(i, CHECK);
 307   int   nof_dims = last_frame.number_of_dimensions();
 308   assert(klass->is_klass(), "not a class");
 309   assert(nof_dims >= 1, "multianewarray rank must be nonzero");
 310 
 311   // We must create an array of jints to pass to multi_allocate.
 312   ResourceMark rm(current);
 313   const int small_dims = 10;
 314   jint dim_array[small_dims];
 315   jint *dims = &dim_array[0];
 316   if (nof_dims > small_dims) {
 317     dims = (jint*) NEW_RESOURCE_ARRAY(jint, nof_dims);
 318   }
 319   for (int index = 0; index < nof_dims; index++) {
 320     // offset from first_size_address is addressed as local[index]
 321     int n = Interpreter::local_offset_in_bytes(index)/jintSize;
 322     dims[index] = first_size_address[n];
 323   }
 324   oop obj = ArrayKlass::cast(klass)->multi_allocate(nof_dims, dims, CHECK);
 325   current->set_vm_result_oop(obj);
 326 JRT_END
 327 
 328 
 329 JRT_ENTRY(void, InterpreterRuntime::register_finalizer(JavaThread* current, oopDesc* obj))
 330   assert(oopDesc::is_oop(obj), "must be a valid oop");
 331   assert(obj->klass()->has_finalizer(), "shouldn't be here otherwise");
 332   InstanceKlass::register_finalizer(instanceOop(obj), CHECK);
 333 JRT_END
 334 
 335 JRT_ENTRY(jboolean, InterpreterRuntime::is_substitutable(JavaThread* current, oopDesc* aobj, oopDesc* bobj))
 336   assert(oopDesc::is_oop(aobj) && oopDesc::is_oop(bobj), "must be valid oops");
 337 
 338   Handle ha(THREAD, aobj);
 339   Handle hb(THREAD, bobj);
 340   JavaValue result(T_BOOLEAN);
 341   JavaCallArguments args;
 342   args.push_oop(ha);
 343   args.push_oop(hb);
 344   methodHandle method(current, Universe::is_substitutable_method());
 345   method->method_holder()->initialize(CHECK_false); // Ensure class ValueObjectMethods is initialized
 346   JavaCalls::call(&result, method, &args, THREAD);
 347   if (HAS_PENDING_EXCEPTION) {
 348     // Something really bad happened because isSubstitutable() should not throw exceptions
 349     // If it is an error, just let it propagate
 350     // If it is an exception, wrap it into an InternalError
 351     if (!PENDING_EXCEPTION->is_a(vmClasses::Error_klass())) {
 352       Handle e(THREAD, PENDING_EXCEPTION);
 353       CLEAR_PENDING_EXCEPTION;
 354       THROW_MSG_CAUSE_(vmSymbols::java_lang_InternalError(), "Internal error in substitutability test", e, false);
 355     }
 356   }
 357   return result.get_jboolean();
 358 JRT_END
 359 
 360 // Quicken instance-of and check-cast bytecodes
 361 JRT_ENTRY(void, InterpreterRuntime::quicken_io_cc(JavaThread* current))
 362   // Force resolving; quicken the bytecode
 363   LastFrameAccessor last_frame(current);
 364   int which = last_frame.get_index_u2(Bytecodes::_checkcast);
 365   ConstantPool* cpool = last_frame.method()->constants();
 366   // We'd expect to assert that we're only here to quicken bytecodes, but in a multithreaded
 367   // program we might have seen an unquick'd bytecode in the interpreter but have another
 368   // thread quicken the bytecode before we get here.
 369   // assert( cpool->tag_at(which).is_unresolved_klass(), "should only come here to quicken bytecodes" );
 370   Klass* klass = cpool->klass_at(which, CHECK);
 371   current->set_vm_result_metadata(klass);
 372 JRT_END
 373 
 374 
 375 //------------------------------------------------------------------------------------------------------------------------
 376 // Exceptions
 377 
 378 void InterpreterRuntime::note_trap_inner(JavaThread* current, int reason,

 686 // and therefore we don't have the receiver object at our fingertips. (Though,
 687 // on some platforms the receiver still resides in a register...). Thus,
 688 // we have no choice but print an error message not containing the receiver
 689 // type.
 690 JRT_ENTRY(void, InterpreterRuntime::throw_AbstractMethodErrorWithMethod(JavaThread* current,
 691                                                                         Method* missingMethod))
 692   ResourceMark rm(current);
 693   assert(missingMethod != nullptr, "sanity");
 694   methodHandle m(current, missingMethod);
 695   LinkResolver::throw_abstract_method_error(m, THREAD);
 696 JRT_END
 697 
 698 JRT_ENTRY(void, InterpreterRuntime::throw_AbstractMethodErrorVerbose(JavaThread* current,
 699                                                                      Klass* recvKlass,
 700                                                                      Method* missingMethod))
 701   ResourceMark rm(current);
 702   methodHandle mh = methodHandle(current, missingMethod);
 703   LinkResolver::throw_abstract_method_error(mh, recvKlass, THREAD);
 704 JRT_END
 705 
 706 JRT_ENTRY(void, InterpreterRuntime::throw_InstantiationError(JavaThread* current))
 707   THROW(vmSymbols::java_lang_InstantiationError());
 708 JRT_END
 709 
 710 
 711 JRT_ENTRY(void, InterpreterRuntime::throw_IncompatibleClassChangeError(JavaThread* current))
 712   THROW(vmSymbols::java_lang_IncompatibleClassChangeError());
 713 JRT_END
 714 
 715 JRT_ENTRY(void, InterpreterRuntime::throw_IncompatibleClassChangeErrorVerbose(JavaThread* current,
 716                                                                               Klass* recvKlass,
 717                                                                               Klass* interfaceKlass))
 718   ResourceMark rm(current);
 719   char buf[1000];
 720   buf[0] = '\0';
 721   jio_snprintf(buf, sizeof(buf),
 722                "Class %s does not implement the requested interface %s",
 723                recvKlass ? recvKlass->external_name() : "nullptr",
 724                interfaceKlass ? interfaceKlass->external_name() : "nullptr");
 725   THROW_MSG(vmSymbols::java_lang_IncompatibleClassChangeError(), buf);
 726 JRT_END
 727 
 728 JRT_ENTRY(void, InterpreterRuntime::throw_NullPointerException(JavaThread* current))
 729   THROW(vmSymbols::java_lang_NullPointerException());

 769 
 770   // Resolution of put instructions to final instance fields with invalid updates (i.e.,
 771   // to final instance fields with updates originating from a method different than <init>)
 772   // is inhibited. A putfield instruction targeting an instance final field must throw
 773   // an IllegalAccessError if the instruction is not in an instance
 774   // initializer method <init>. If resolution were not inhibited, a putfield
 775   // in an initializer method could be resolved in the initializer. Subsequent
 776   // putfield instructions to the same field would then use cached information.
 777   // As a result, those instructions would not pass through the VM. That is,
 778   // checks in resolve_field_access() would not be executed for those instructions
 779   // and the required IllegalAccessError would not be thrown.
 780   //
 781   // Also, we need to delay resolving getstatic and putstatic instructions until the
 782   // class is initialized.  This is required so that access to the static
 783   // field will call the initialization function every time until the class
 784   // is completely initialized ala. in 2.17.5 in JVM Specification.
 785   InstanceKlass* klass = info.field_holder();
 786   bool uninitialized_static = is_static && !klass->is_initialized();
 787   bool has_initialized_final_update = info.field_holder()->major_version() >= 53 &&
 788                                       info.has_initialized_final_update();
 789   bool strict_static_final = info.is_strict() && info.is_static() && info.is_final();
 790   assert(!(has_initialized_final_update && !info.access_flags().is_final()), "Fields with initialized final updates must be final");
 791 
 792   Bytecodes::Code get_code = (Bytecodes::Code)0;
 793   Bytecodes::Code put_code = (Bytecodes::Code)0;
 794   if (uninitialized_static && (info.is_strict_static_unset() || strict_static_final)) {
 795     // During <clinit>, closely track the state of strict statics.
 796     // 1. if we are reading an uninitialized strict static, throw
 797     // 2. if we are writing one, clear the "unset" flag
 798     //
 799     // Note: If we were handling an attempted write of a null to a
 800     // null-restricted strict static, we would NOT clear the "unset"
 801     // flag.
 802     assert(klass->is_being_initialized(), "else should have thrown");
 803     assert(klass->is_reentrant_initialization(THREAD),
 804       "<clinit> must be running in current thread");
 805     klass->notify_strict_static_access(info.index(), is_put, CHECK);
 806     assert(!info.is_strict_static_unset(), "after initialization, no unset flags");
 807   } else if (!uninitialized_static || VM_Version::supports_fast_class_init_checks()) {
 808     get_code = ((is_static) ? Bytecodes::_getstatic : Bytecodes::_getfield);
 809     if ((is_put && !has_initialized_final_update) || !info.access_flags().is_final()) {
 810       put_code = ((is_static) ? Bytecodes::_putstatic : Bytecodes::_putfield);
 811     }
 812   }
 813 
 814   ResolvedFieldEntry* entry = pool->resolved_field_entry_at(field_index);
 815   entry->set_flags(info.access_flags().is_volatile(),
 816                    info.access_flags().is_final(),
 817                    info.is_flat(),
 818                    info.is_null_free_inline_type(),
 819                    info.has_null_marker());
 820 
 821   entry->fill_in(info.field_holder(), info.offset(),
 822                  checked_cast<u2>(info.index()), checked_cast<u1>(state),
 823                  static_cast<u1>(get_code), static_cast<u1>(put_code));
 824 }
 825 
 826 
 827 //------------------------------------------------------------------------------------------------------------------------
 828 // Synchronization
 829 //
 830 // The interpreter's synchronization code is factored out so that it can
 831 // be shared by method invocation and synchronized blocks.
 832 //%note synchronization_3
 833 
 834 //%note monitor_1
 835 JRT_ENTRY_NO_ASYNC(void, InterpreterRuntime::monitorenter(JavaThread* current, BasicObjectLock* elem))
 836 #ifdef ASSERT
 837   current->last_frame().interpreter_frame_verify_monitor(elem);
 838 #endif
 839   Handle h_obj(current, elem->obj());
 840   assert(Universe::heap()->is_in_or_null(h_obj()),

 847 #endif
 848 JRT_END
 849 
 850 JRT_LEAF(void, InterpreterRuntime::monitorexit(BasicObjectLock* elem))
 851   oop obj = elem->obj();
 852   assert(Universe::heap()->is_in(obj), "must be an object");
 853   // The object could become unlocked through a JNI call, which we have no other checks for.
 854   // Give a fatal message if CheckJNICalls. Otherwise we ignore it.
 855   if (obj->is_unlocked()) {
 856     if (CheckJNICalls) {
 857       fatal("Object has been unlocked by JNI");
 858     }
 859     return;
 860   }
 861   ObjectSynchronizer::exit(obj, elem->lock(), JavaThread::current());
 862   // Free entry. If it is not cleared, the exception handling code will try to unlock the monitor
 863   // again at method exit or in the case of an exception.
 864   elem->set_obj(nullptr);
 865 JRT_END
 866 

 867 JRT_ENTRY(void, InterpreterRuntime::throw_illegal_monitor_state_exception(JavaThread* current))
 868   THROW(vmSymbols::java_lang_IllegalMonitorStateException());
 869 JRT_END
 870 

 871 JRT_ENTRY(void, InterpreterRuntime::new_illegal_monitor_state_exception(JavaThread* current))
 872   // Returns an illegal exception to install into the current thread. The
 873   // pending_exception flag is cleared so normal exception handling does not
 874   // trigger. Any current installed exception will be overwritten. This
 875   // method will be called during an exception unwind.
 876 
 877   assert(!HAS_PENDING_EXCEPTION, "no pending exception");
 878   Handle exception(current, current->vm_result_oop());
 879   assert(exception() != nullptr, "vm result should be set");
 880   current->set_vm_result_oop(nullptr); // clear vm result before continuing (may cause memory leaks and assert failures)
 881   exception = get_preinitialized_exception(vmClasses::IllegalMonitorStateException_klass(), CATCH);
 882   current->set_vm_result_oop(exception());
 883 JRT_END
 884 
 885 JRT_ENTRY(void, InterpreterRuntime::throw_identity_exception(JavaThread* current, oopDesc* obj))
 886   Klass* klass = cast_to_oop(obj)->klass();
 887   ResourceMark rm(THREAD);
 888   const char* desc = "Cannot synchronize on an instance of value class ";
 889   const char* className = klass->external_name();
 890   size_t msglen = strlen(desc) + strlen(className) + 1;
 891   char* message = NEW_RESOURCE_ARRAY(char, msglen);
 892   if (nullptr == message) {
 893     // Out of memory: can't create detailed error message
 894     THROW_MSG(vmSymbols::java_lang_IdentityException(), className);
 895   } else {
 896     jio_snprintf(message, msglen, "%s%s", desc, className);
 897     THROW_MSG(vmSymbols::java_lang_IdentityException(), message);
 898   }
 899 JRT_END
 900 
 901 //------------------------------------------------------------------------------------------------------------------------
 902 // Invokes
 903 
 904 JRT_ENTRY(Bytecodes::Code, InterpreterRuntime::get_original_bytecode_at(JavaThread* current, Method* method, address bcp))
 905   return method->orig_bytecode_at(method->bci_from(bcp));
 906 JRT_END
 907 
 908 JRT_ENTRY(void, InterpreterRuntime::set_original_bytecode_at(JavaThread* current, Method* method, address bcp, Bytecodes::Code new_code))
 909   method->set_orig_bytecode_at(method->bci_from(bcp), new_code);
 910 JRT_END
 911 
 912 JRT_ENTRY(void, InterpreterRuntime::_breakpoint(JavaThread* current, Method* method, address bcp))
 913   JvmtiExport::post_raw_breakpoint(current, method, bcp);
 914 JRT_END
 915 
 916 void InterpreterRuntime::resolve_invoke(Bytecodes::Code bytecode, TRAPS) {
 917   JavaThread* current = THREAD;
 918   LastFrameAccessor last_frame(current);
 919   // extract receiver from the outgoing argument list if necessary

1293     JvmtiExport::at_single_stepping_point(current, last_frame.method(), last_frame.bcp());
1294   }
1295 JRT_END
1296 
1297 JRT_LEAF(void, InterpreterRuntime::at_unwind(JavaThread* current))
1298   assert(current == JavaThread::current(), "pre-condition");
1299   JFR_ONLY(Jfr::check_and_process_sample_request(current);)
1300   // This function is called by the interpreter when the return poll found a reason
1301   // to call the VM. The reason could be that we are returning into a not yet safe
1302   // to access frame. We handle that below.
1303   // Note that this path does not check for single stepping, because we do not want
1304   // to single step when unwinding frames for an exception being thrown. Instead,
1305   // such single stepping code will use the safepoint table, which will use the
1306   // InterpreterRuntime::at_safepoint callback.
1307   StackWatermarkSet::before_unwind(current);
1308 JRT_END
1309 
1310 JRT_ENTRY(void, InterpreterRuntime::post_field_access(JavaThread* current, oopDesc* obj,
1311                                                       ResolvedFieldEntry *entry))
1312 
1313   assert(entry->is_valid(), "Invalid ResolvedFieldEntry");
1314   // check the access_flags for the field in the klass
1315 
1316   InstanceKlass* ik = entry->field_holder();
1317   int index = entry->field_index();
1318   if (!ik->field_status(index).is_access_watched()) return;
1319 
1320   bool is_static = (obj == nullptr);
1321   bool is_flat = entry->is_flat();
1322   HandleMark hm(current);
1323 
1324   Handle h_obj;
1325   if (!is_static) {
1326     // non-static field accessors have an object, but we need a handle
1327     h_obj = Handle(current, obj);
1328   }
1329   InstanceKlass* field_holder = entry->field_holder(); // HERE
1330   jfieldID fid = jfieldIDWorkaround::to_jfieldID(field_holder, entry->field_offset(), is_static, is_flat);
1331   LastFrameAccessor last_frame(current);
1332   JvmtiExport::post_field_access(current, last_frame.method(), last_frame.bcp(), field_holder, h_obj, fid);
1333 JRT_END
1334 
1335 JRT_ENTRY(void, InterpreterRuntime::post_field_modification(JavaThread* current, oopDesc* obj,
1336                                                             ResolvedFieldEntry *entry, jvalue *value))
1337 
1338   assert(entry->is_valid(), "Invalid ResolvedFieldEntry");
1339   InstanceKlass* ik = entry->field_holder();
1340 
1341   // check the access_flags for the field in the klass
1342   int index = entry->field_index();
1343   // bail out if field modifications are not watched
1344   if (!ik->field_status(index).is_modification_watched()) return;
1345 
1346   char sig_type = '\0';
1347 
1348   switch((TosState)entry->tos_state()) {
1349     case btos: sig_type = JVM_SIGNATURE_BYTE;    break;
1350     case ztos: sig_type = JVM_SIGNATURE_BOOLEAN; break;
1351     case ctos: sig_type = JVM_SIGNATURE_CHAR;    break;
1352     case stos: sig_type = JVM_SIGNATURE_SHORT;   break;
1353     case itos: sig_type = JVM_SIGNATURE_INT;     break;
1354     case ftos: sig_type = JVM_SIGNATURE_FLOAT;   break;
1355     case atos: sig_type = JVM_SIGNATURE_CLASS;   break;
1356     case ltos: sig_type = JVM_SIGNATURE_LONG;    break;
1357     case dtos: sig_type = JVM_SIGNATURE_DOUBLE;  break;
1358     default:  ShouldNotReachHere(); return;
1359   }
1360 
1361   bool is_static = (obj == nullptr);
1362   bool is_flat = entry->is_flat();
1363 
1364   HandleMark hm(current);
1365   jfieldID fid = jfieldIDWorkaround::to_jfieldID(ik, entry->field_offset(), is_static, is_flat);
1366   jvalue fvalue;
1367 #ifdef _LP64
1368   fvalue = *value;
1369 #else
1370   // Long/double values are stored unaligned and also noncontiguously with
1371   // tagged stacks.  We can't just do a simple assignment even in the non-
1372   // J/D cases because a C++ compiler is allowed to assume that a jvalue is
1373   // 8-byte aligned, and interpreter stack slots are only 4-byte aligned.
1374   // We assume that the two halves of longs/doubles are stored in interpreter
1375   // stack slots in platform-endian order.
1376   jlong_accessor u;
1377   jint* newval = (jint*)value;
1378   u.words[0] = newval[0];
1379   u.words[1] = newval[Interpreter::stackElementWords]; // skip if tag
1380   fvalue.j = u.long_value;
1381 #endif // _LP64
1382 
1383   Handle h_obj;
1384   if (!is_static) {
1385     // non-static field accessors have an object, but we need a handle
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